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d4ad4976c81a20e89ecc901ce022a047d9f0fe3f | wikidoc | EpiPen | EpiPen
# Disclaimer
WikiDoc MAKES NO GUARANTEE OF VALIDITY. WikiDoc is not a professional health care provider, nor is it a suitable replacement for a licensed healthcare provider. WikiDoc is intended to be an educational tool, not a tool for any form of healthcare delivery. The educational content on WikiDoc drug pages is based upon the FDA package insert, National Library of Medicine content and practice guidelines / consensus statements. WikiDoc does not promote the administration of any medication or device that is not consistent with its labeling. Please read our full disclaimer here.
# Overview
EpiPen is a non-selective alpha and beta-adrenergic receptor agonist that is FDA approved for the {{{indicationType}}} of allergic reactions (Type I) including anaphylaxis. Common adverse reactions include anxiety, apprehensiveness, restlessness, tremor, weakness, dizziness, sweating, palpitations, pallor, nausea and vomiting, headache, and/or respiratory difficulties..
# Adult Indications and Dosage
## FDA-Labeled Indications and Dosage (Adult)
- EpiPen and EpiPen Jr are indicated in the emergency treatment of allergic reactions (Type I) including anaphylaxis to stinging insects (e.g., order Hymenoptera, which include bees, wasps, hornets, yellow jackets and fire ants) and biting insects (e.g., triatoma, mosquitoes), allergen immunotherapy, foods, drugs, diagnostic testing substances (e.g., radiocontrast media) and other allergens, as well as idiopathic anaphylaxis or exercise-induced anaphylaxis.
- EpiPen and EpiPen Jr are intended for immediate administration in patients who are determined to be at increased risk for anaphylaxis, including individuals with a history of anaphylactic reactions.
- Anaphylactic reactions may occur within minutes after exposure and consist of flushing, apprehension, syncope, tachycardia, thready or unobtainable pulse associated with a fall in blood pressure, convulsions, vomiting, diarrhea and abdominal cramps, involuntary voiding, wheezing, dyspnea due to laryngeal spasm, pruritus, rashes, urticaria or angioedema.
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy only and are not a substitute for immediate medical care.
- Dosing Information
- Selection of the appropriate dosage strength (EpiPen 0.3 mg or EpiPen Jr 0.15 mg) is determined according to patient body weight.
Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
- Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Inject EpiPen or EpiPen Jr intramuscularly or subcutaneously into the anterolateral aspect of the thigh, through clothing if necessary.
- Each EpiPen or EpiPen Jr contains a single dose of epinephrine for single-use injection. Since the doses of epinephrine delivered from EpiPen or EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
## Off-Label Use and Dosage (Adult)
### Guideline-Supported Use
- Developed by: ACC/AHA
- Class of Recommendation: Class IIb
- Strength of Evidence: Category B
- If atropine is ineffective for the treatment of bradycardia with a pulse, then epinephrine or dopamine may be used, especially, with associated hypotension.
### Non–Guideline-Supported Use
- Endoscopic injection of epinephrine is effective in the treatment of upper gastrointestinal hemorrhage.
# Pediatric Indications and Dosage
## FDA-Labeled Indications and Dosage (Pediatric)
- EpiPen and EpiPen Jr are indicated in the emergency treatment of allergic reactions (Type I) including anaphylaxis to stinging insects (e.g., order Hymenoptera, which include bees, wasps, hornets, yellow jackets and fire ants) and biting insects (e.g., triatoma, mosquitoes), allergen immunotherapy, foods, drugs, diagnostic testing substances (e.g., radiocontrast media) and other allergens, as well as idiopathic anaphylaxis or exercise-induced anaphylaxis.
- EpiPen and EpiPen Jr are intended for immediate administration in patients who are determined to be at increased risk for anaphylaxis, including individuals with a history of anaphylactic reactions.
- Anaphylactic reactions may occur within minutes after exposure and consist of flushing, apprehension, syncope, tachycardia, thready or unobtainable pulse associated with a fall in blood pressure, convulsions, vomiting, diarrhea and abdominal cramps, involuntary voiding, wheezing, dyspnea due to laryngeal spasm, pruritus, rashes, urticaria or angioedema.
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy only and are not a substitute for immediate medical care.
- Dosing Information
- Selection of the appropriate dosage strength (EpiPen 0.3 mg or EpiPen Jr 0.15 mg) is determined according to patient body weight.
Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
- Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Inject EpiPen or EpiPen Jr intramuscularly or subcutaneously into the anterolateral aspect of the thigh, through clothing if necessary.
- Each EpiPen or EpiPen Jr contains a single dose of epinephrine for single-use injection. Since the doses of epinephrine delivered from EpiPen or EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
## Off-Label Use and Dosage (Pediatric)
### Guideline-Supported Use
There is limited information regarding Off-Label Guideline-Supported Use of EpiPen in pediatric patients.
### Non–Guideline-Supported Use
- Aerosolized levo-epinephrine (1:1000) is at least as effective as racemic epinephrine (2.25%) in the treatment of laryngotracheitis in children (6 months to 6 years of age) with moderate to severe croup.
- Subcutaneous epinephrine is effective in the treatment of acute wheezing in children less than 2 years of age.
# Contraindications
- None
# Warnings
### Precautions
- Emergency Treatment
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy and are not intended as a substitute for immediate medical care. In conjunction with the administration of epinephrine, the patient should seek immediate medical or hospital care. More than two sequential doses of epinephrine should only be administered under direct medical supervision.
- Incorrect Locations of Injection
- EpiPen and EpiPen Jr should only be injected into the anterolateral aspect of the thigh .
Do not inject intravenously. Large doses or accidental intravenous injection of epinephrine may result in cerebral hemorrhage due to sharp rise in blood pressure. Rapidly acting vasodilators can counteract the marked pressor effects of epinephrine if there is such inadvertent administration.
Do not inject into buttock. Injection into the buttock may not provide effective treatment of anaphylaxis. Advise the patient to go immediately to the nearest emergency room for further treatment of anaphylaxis. Additionally, injection into the buttock has been associated with gas gangrene. Cleansing with alcohol does not kill bacterial spores, and therefore, does not lower this risk.
Do not inject into digits, hands or feet. Since epinephrine is a strong vasoconstrictor, accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area. Advise the patient to go immediately to the nearest emergency room and to inform the healthcare provider in the emergency room of the location of the accidental injection. Treatment of such inadvertent administration should consist of vasodilation, in addition to further appropriate treatment of anaphylaxis .
- Do not inject intravenously. Large doses or accidental intravenous injection of epinephrine may result in cerebral hemorrhage due to sharp rise in blood pressure. Rapidly acting vasodilators can counteract the marked pressor effects of epinephrine if there is such inadvertent administration.
- Do not inject into buttock. Injection into the buttock may not provide effective treatment of anaphylaxis. Advise the patient to go immediately to the nearest emergency room for further treatment of anaphylaxis. Additionally, injection into the buttock has been associated with gas gangrene. Cleansing with alcohol does not kill bacterial spores, and therefore, does not lower this risk.
- Do not inject into digits, hands or feet. Since epinephrine is a strong vasoconstrictor, accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area. Advise the patient to go immediately to the nearest emergency room and to inform the healthcare provider in the emergency room of the location of the accidental injection. Treatment of such inadvertent administration should consist of vasodilation, in addition to further appropriate treatment of anaphylaxis .
- Allergic Reactions Associated With Sulfite
- The presence of a sulfite in this product should not deter administration of the drug for treatment of serious allergic or other emergency situations even if the patient is sulfite-sensitive.
- Epinephrine is the preferred treatment for serious allergic reactions or other emergency situations even though this product contains sodium metabisulfite, a sulfite that may, in other products, cause allergic-type reactions including anaphylactic symptoms or life-threatening or less severe asthmatic episodes in certain susceptible persons.
- The alternatives to using epinephrine in a life-threatening situation may not be satisfactory.
- Disease Interactions
- Some patients may be at greater risk for developing adverse reactions after epinephrine administration. Despite these concerns, it should be recognized that the presence of these conditions is not a contraindication to epinephrine administration in an acute, life-threatening situation. Therefore, patients with these conditions, and/or any other person who might be in a position to administer EpiPen or EpiPen Jr to a patient experiencing anaphylaxis should be carefully instructed in regard to the circumstances under which epinephrine should be used.
- Patients with Heart Disease
- Epinephrine should be administered with caution to patients who have heart disease, including patients with cardiac arrhythmias, coronary artery or organic heart disease, or hypertension. In such patients, or in patients who are on drugs that may sensitize the heart to arrhythmias, epinephrine may precipitate or aggravate angina pectoris as well as produce ventricular arrhythmias.
- Other Patients and Diseases
- Epinephrine should be administered with caution to patients with hyperthyroidism, diabetes, elderly individuals, and pregnant women. Patients with Parkinson’s disease may notice a temporary worsening of symptoms.
# Adverse Reactions
## Clinical Trials Experience
- Due to the lack of randomized, controlled clinical trials of epinephrine for the treatment of anaphylaxis, the true incidence of adverse reactions associated with the systemic use of epinephrine is difficult to determine. Adverse reactions reported in observational trials, case reports, and studies are listed below.
- Common adverse reactions to systemically administered epinephrine include anxiety; apprehensiveness; restlessness; tremor; weakness; dizziness; sweating; palpitations; pallor; nausea and vomiting; headache; and/or respiratory difficulties. These symptoms occur in some persons receiving therapeutic doses of epinephrine, but are more likely to occur in patients with hypertension or hyperthyroidism .
- Arrhythmias, including fatal ventricular fibrillation, have been reported, particularly in patients with underlying cardiac disease or those receiving certain drugs .
- Rapid rises in blood pressure have produced cerebral hemorrhage, particularly in elderly patients with cardiovascular disease .
- Angina may occur in patients with coronary artery disease .
- Accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area .
- Adverse events experienced as a result of accidental injections may include increased heart rate, local reactions including injection site pallor, coldness and hypoesthesia or injury at the injection site resulting in bruising, bleeding, discoloration, erythema or skeletal injury.
- Injection into the buttock has resulted in cases of gas gangrene.
## Postmarketing Experience
There is limited information regarding Postmarketing Experience of EpiPen in the drug label.
# Drug Interactions
- Patients who receive epinephrine while concomitantly taking cardiac glycosides, diuretics, or anti-arrhythmics should be observed carefully for the development of cardiac arrhythmias .
- The effects of epinephrine may be potentiated by tricyclic antidepressants, monoamine oxidase inhibitors, levothyroxine sodium, and certain antihistamines, notably chlorpheniramine, tripelennamine, and diphenhydramine.
- The cardiostimulating and bronchodilating effects of epinephrine are antagonized by beta- adrenergic blocking drugs, such as propranolol.
- The vasoconstricting and hypertensive effects of epinephrine are antagonized by alpha- adrenergic blocking drugs, such as phentolamine.
- Ergot alkaloids may also reverse the pressor effects of epinephrine.
# Use in Specific Populations
### Pregnancy
Pregnancy Category (FDA):
- Pregnancy Category C
- There are no adequate and well controlled studies of the acute effect of epinephrine in pregnant women.
- Epinephrine was teratogenic in rabbits, mice and hamsters. Epinephrine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus (fetal anoxia, spontaneous abortion, or both).
- Epinephrine has been shown to have teratogenic effects when administered subcutaneously in rabbits at approximately 30 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal dose of 1.2 mg/kg/day for two to three days), in mice at approximately 7 times the maximum daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal subcutaneous dose of 1 mg/kg/day for 10 days), and in hamsters at approximately 5 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal subcutaneous dose of 0.5 mg/kg/day for 4 days).
- These effects were not seen in mice at approximately 3 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a subcutaneous maternal dose of 0.5 mg/kg/day for 10 days).
Pregnancy Category (AUS):
- Australian Drug Evaluation Committee (ADEC) Pregnancy Category
There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of EpiPen in women who are pregnant.
### Labor and Delivery
There is no FDA guidance on use of EpiPen during labor and delivery.
### Nursing Mothers
- It is not known whether epinephrine is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when EpiPen is administered to a nursing woman.
### Pediatric Use
- EpiPen or EpiPen Jr may be administered to pediatric patients at a dosage appropriate to body weight. Clinical experience with the use of epinephrine suggests that the adverse reactions seen in children are similar in nature and extent to those both expected and reported in adults. Since the doses of epinephrine delivered from EpiPen and EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
### Geriatic Use
- Clinical studies for the treatment of anaphylaxis have not been performed in subjects aged 65 and over to determine whether they respond differently from younger subjects. However, other reported clinical experience with use of epinephrine for the treatment of anaphylaxis has identified that geriatric patients may be particularly sensitive to the effects of epinephrine. Therefore, EpiPen should be administered with caution in elderly individuals, who may be at greater risk for developing adverse reactions after epinephrine administration.
### Gender
There is no FDA guidance on the use of EpiPen with respect to specific gender populations.
### Race
There is no FDA guidance on the use of EpiPen with respect to specific racial populations.
### Renal Impairment
There is no FDA guidance on the use of EpiPen in patients with renal impairment.
### Hepatic Impairment
There is no FDA guidance on the use of EpiPen in patients with hepatic impairment.
### Females of Reproductive Potential and Males
There is no FDA guidance on the use of EpiPen in women of reproductive potentials and males.
### Immunocompromised Patients
There is no FDA guidance one the use of EpiPen in patients who are immunocompromised.
# Administration and Monitoring
### Administration
- Intramuscular
### Monitoring
There is limited information regarding Monitoring of EpiPen in the drug label.
# IV Compatibility
There is limited information regarding IV Compatibility of EpiPen in the drug label.
# Overdosage
## Acute Overdose
### Signs and Symptoms
- Overdosage of epinephrine may produce extremely elevated arterial pressure, which may result in cerebrovascular hemorrhage, particularly in elderly patients. Overdosage may also result in pulmonary edema because of peripheral vascular constriction together with cardiac stimulation. Treatment consists of rapidly acting vasodilators or alpha-adrenergic blocking drugs and/or respiratory support.
- Epinephrine overdosage can also cause transient bradycardia followed by tachycardia, and these may be accompanied by potentially fatal cardiac arrhythmias. Premature ventricular contractions may appear within one minute after injection and may be followed by multifocal ventricular tachycardia (prefibrillation rhythm). Subsidence of the ventricular effects may be followed by atrial tachycardia and occasionally by atrioventricular block. Treatment of arrhythmias consists of administration of a beta-adrenergic blocking drug such as propranolol.
- Overdosage sometimes results in extreme pallor and coldness of the skin, metabolic acidosis, and kidney failure.
### Management
- Suitable corrective measures must be taken in such situations.
## Chronic Overdose
There is limited information regarding Chronic Overdose of EpiPen in the drug label.
# Pharmacology
## Mechanism of Action
- Epinephrine acts on both alpha- and beta-adrenergic receptors.
## Structure
- EpiPen (epinephrine injection, USP) 0.3 mg and EpiPen Jr (epinephrine injection, USP) 0.15 mg are auto-injectors and combination products containing drug and device components.
- Each EpiPen Auto-Injector, 0.3 mg delivers a single dose of 0.3 mg epinephrine from epinephrine injection, USP 1:1000 (0.3 mL) in a sterile solution.
- Each EpiPen Jr Auto-Injector, 0.15 mg delivers a single dose of 0.15 mg epinephrine from epinephrine injection, USP 1:2000 (0.3 mL) in a sterile solution.
- The EpiPen and EpiPen Jr each contain 2 mL epinephrine solution. Approximately 1.7 mL remains in the auto-injector after activation, but is not available for future use, and should be discarded.
- Each 0.3 mL in the EpiPen Auto-Injector contains 0.3 mg epinephrine, 1.8 mg sodium chloride, 0.5 mg sodium metabisulfite, hydrochloric acid to adjust pH, and Water for Injection. The pH range is 2.2–5.0.
- Each 0.3 mL in the EpiPen Jr Auto-Injector contains 0.15 mg epinephrine, 1.8 mg sodium chloride, 0.5 mg sodium metabisulfite, hydrochloric acid to adjust pH, and Water for Injection. The pH range is 2.2-5.0.
- Epinephrine is a sympathomimetic catecholamine. Chemically, epinephrine is (-)-3,4- Dihydroxy-α-benzyl alcohol with the following structure:
- Epinephrine solution deteriorates rapidly on exposure to air or light, turning pink from oxidation to adrenochrome and brown from the formation of melanin. Replace EpiPen and EpiPen Jr if the epinephrine solution appears discolored (pinkish or brown color), cloudy, or contains particles.
- Thoroughly review the patient instructions and operation of EpiPen or EpiPen Jr with patients and caregivers prior to use.
## Pharmacodynamics
- Through its action on alpha-adrenergic receptors, epinephrine lessens the vasodilation and increased vascular permeability that occurs during anaphylaxis, which can lead to loss of intravascular fluid volume and hypotension.
- Through its action on beta-adrenergic receptors, epinephrine causes bronchial smooth muscle relaxation and helps alleviate bronchospasm, wheezing and dyspnea that may occur during anaphylaxis.
- Epinephrine also alleviates pruritus, urticaria, and angioedema and may relieve gastrointestinal and genitourinary symptoms associated with anaphylaxis because of its relaxer effects on the smooth muscle of the stomach, intestine, uterus and urinary bladder.
- When given subcutaneously or intramuscularly, epinephrine has a rapid onset and short duration of action.
## Pharmacokinetics
There is limited information regarding Pharmacokinetics of EpiPen in the drug label.
## Nonclinical Toxicology
- Long-term studies to evaluate the carcinogenic potential of epinephrine have not been conducted.
- Epinephrine and other catecholamines have been shown to have mutagenic potential in vitro and to be an oxidative mutagen in a WP2 bacterial reverse mutation assay.
- Epinephrine was positive in the DNA Repair test with B. subtilis (REC) assay, but was not mutagenic in the Salmonella bacterial reverse mutation assay.
- The potential for epinephrine to impair fertility has not been evaluated.
# Clinical Studies
There is limited information regarding Clinical Studies of EpiPen in the drug label.
# How Supplied
- EpiPen Auto-Injectors (epinephrine injections, USP, 1:1000, 0.3 mL) are available as EpiPen 2-Pak®, NDC 49502-500-02, a pack that contains two EpiPen Auto-Injectors (epinephrine injections, USP, 1:1000, 0.3 mL) and one EpiPen Auto-Injector trainer device.
- EpiPen Jr Auto-Injectors (epinephrine injections, USP, 1:2000, 0.3 mL) are available as EpiPen Jr 2-Pak®, NDC 49502-501-02, a pack that contains two EpiPen Jr Auto-Injectors (epinephrine injections, USP, 1:2000, 0.3 mL) and one EpiPen Auto-Injector trainer device.
- EpiPen 2-Pak® and EpiPen Jr 2-Pak® also includes an S-clip to clip two carrier tubes together.
- Storage and Handling
- Protect from light. Epinephrine is light sensitive and should be stored in the carrier tube provided to protect it from light. Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) (See USP Controlled Room Temperature). Do not refrigerate. Before using, check to make sure the solution in the auto-injector is clear and colorless. Replace the auto-injector if the solution is discolored (pinkish or brown color), cloudy, or contains particles.
## Storage
There is limited information regarding EpiPen Storage in the drug label.
# Images
## Drug Images
## Package and Label Display Panel
# Patient Counseling Information
- A healthcare provider should review the patient instructions and operation of EpiPen and EpiPen Jr in detail, with the patient or caregiver.
- Epinephrine is essential for the treatment of anaphylaxis. Patients who are at risk of or with a history of severe allergic reactions (anaphylaxis) to insect stings or bites, foods, drugs, and other allergens, as well as idiopathic and exercise-induced anaphylaxis, should be carefully instructed about the circumstances under which epinephrine should be used.
- Administration and Training
- Patients and/or caregivers should be instructed in the appropriate use of EpiPen and EpiPen Jr. EpiPen should be injected into the middle of the outer thigh (through clothing, if necessary). Each device is a single-use injection. Advise patients to seek immediate medical care in conjunction with administration of EpiPen.
- Complete patient information, including dosage, directions for proper administration and precautions can be found inside each EpiPen or EpiPen Jr carton. A printed label on the surface of EpiPen shows instructions for use and a diagram depicting the injection process.
- Patients and/or caregivers should be instructed to use the Trainer to familiarize themselves with the use of EpiPen in an allergic emergency. The Trainer may be used multiple times. A Trainer device is provided in 2-Pak cartons.
- Adverse Reactions
- Epinephrine may produce symptoms and signs that include an increase in heart rate, the sensation of a more forceful heartbeat, palpitations, sweating, nausea and vomiting, difficulty breathing, pallor, dizziness, weakness or shakiness, headache, apprehension, nervousness, or anxiety. These signs and symptoms usually subside rapidly, especially with rest, quiet and recumbency. Patients with hypertension or hyperthyroidism may develop more severe or persistent effects, and patients with coronary artery disease could experience angina. Patients with diabetes may develop increased blood glucose levels following epinephrine administration. Patients with Parkinson’s disease may notice a temporary worsening of symptoms.
- Accidental Injection
- Advise patients to seek immediate medical care in the case of accidental injection. Since epinephrine is a strong vasoconstrictor when injected into the digits, hands, or feet, treatment should be directed at vasodilatation if there is such an accidental injection to these areas.
- Storage and Handling
- Instruct patients to inspect the epinephrine solution visually through the clear window of the auto-injector periodically. EpiPen and EpiPen Jr should be replaced if the epinephrine solution appears discolored (pinkish or brown color), cloudy, or contains particles. Epinephrine is light sensitive and should be stored in the carrier tube provided to protect it from light. The carrier tube is not waterproof. Patients should be instructed that EpiPen and EpiPen Jr must be used or properly disposed once the blue safety release is removed or after use.
# Precautions with Alcohol
- Alcohol-EpiPen interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
# Brand Names
- EpiPen®
# Look-Alike Drug Names
- EPINEPHrine® — ePHEDrine®
# Drug Shortage Status
# Price | EpiPen
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Vignesh Ponnusamy, M.B.B.S. [2]
# Disclaimer
WikiDoc MAKES NO GUARANTEE OF VALIDITY. WikiDoc is not a professional health care provider, nor is it a suitable replacement for a licensed healthcare provider. WikiDoc is intended to be an educational tool, not a tool for any form of healthcare delivery. The educational content on WikiDoc drug pages is based upon the FDA package insert, National Library of Medicine content and practice guidelines / consensus statements. WikiDoc does not promote the administration of any medication or device that is not consistent with its labeling. Please read our full disclaimer here.
# Overview
EpiPen is a non-selective alpha and beta-adrenergic receptor agonist that is FDA approved for the {{{indicationType}}} of allergic reactions (Type I) including anaphylaxis. Common adverse reactions include anxiety, apprehensiveness, restlessness, tremor, weakness, dizziness, sweating, palpitations, pallor, nausea and vomiting, headache, and/or respiratory difficulties..
# Adult Indications and Dosage
## FDA-Labeled Indications and Dosage (Adult)
- EpiPen and EpiPen Jr are indicated in the emergency treatment of allergic reactions (Type I) including anaphylaxis to stinging insects (e.g., order Hymenoptera, which include bees, wasps, hornets, yellow jackets and fire ants) and biting insects (e.g., triatoma, mosquitoes), allergen immunotherapy, foods, drugs, diagnostic testing substances (e.g., radiocontrast media) and other allergens, as well as idiopathic anaphylaxis or exercise-induced anaphylaxis.
- EpiPen and EpiPen Jr are intended for immediate administration in patients who are determined to be at increased risk for anaphylaxis, including individuals with a history of anaphylactic reactions.
- Anaphylactic reactions may occur within minutes after exposure and consist of flushing, apprehension, syncope, tachycardia, thready or unobtainable pulse associated with a fall in blood pressure, convulsions, vomiting, diarrhea and abdominal cramps, involuntary voiding, wheezing, dyspnea due to laryngeal spasm, pruritus, rashes, urticaria or angioedema.
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy only and are not a substitute for immediate medical care.
- Dosing Information
- Selection of the appropriate dosage strength (EpiPen 0.3 mg or EpiPen Jr 0.15 mg) is determined according to patient body weight.
Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
- Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Inject EpiPen or EpiPen Jr intramuscularly or subcutaneously into the anterolateral aspect of the thigh, through clothing if necessary.
- Each EpiPen or EpiPen Jr contains a single dose of epinephrine for single-use injection. Since the doses of epinephrine delivered from EpiPen or EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
## Off-Label Use and Dosage (Adult)
### Guideline-Supported Use
- Developed by: ACC/AHA
- Class of Recommendation: Class IIb
- Strength of Evidence: Category B
- If atropine is ineffective for the treatment of bradycardia with a pulse, then epinephrine or dopamine may be used, especially, with associated hypotension.[1]
### Non–Guideline-Supported Use
- Endoscopic injection of epinephrine is effective in the treatment of upper gastrointestinal hemorrhage.[2][3][4]
# Pediatric Indications and Dosage
## FDA-Labeled Indications and Dosage (Pediatric)
- EpiPen and EpiPen Jr are indicated in the emergency treatment of allergic reactions (Type I) including anaphylaxis to stinging insects (e.g., order Hymenoptera, which include bees, wasps, hornets, yellow jackets and fire ants) and biting insects (e.g., triatoma, mosquitoes), allergen immunotherapy, foods, drugs, diagnostic testing substances (e.g., radiocontrast media) and other allergens, as well as idiopathic anaphylaxis or exercise-induced anaphylaxis.
- EpiPen and EpiPen Jr are intended for immediate administration in patients who are determined to be at increased risk for anaphylaxis, including individuals with a history of anaphylactic reactions.
- Anaphylactic reactions may occur within minutes after exposure and consist of flushing, apprehension, syncope, tachycardia, thready or unobtainable pulse associated with a fall in blood pressure, convulsions, vomiting, diarrhea and abdominal cramps, involuntary voiding, wheezing, dyspnea due to laryngeal spasm, pruritus, rashes, urticaria or angioedema.
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy only and are not a substitute for immediate medical care.
- Dosing Information
- Selection of the appropriate dosage strength (EpiPen 0.3 mg or EpiPen Jr 0.15 mg) is determined according to patient body weight.
Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Patients greater than or equal to 30 kg (approximately 66 pounds or more): EpiPen 0.3 mg
- Patients 15 to 30 kg (33 pounds to 66 pounds): EpiPen Jr 0.15 mg
- Inject EpiPen or EpiPen Jr intramuscularly or subcutaneously into the anterolateral aspect of the thigh, through clothing if necessary.
- Each EpiPen or EpiPen Jr contains a single dose of epinephrine for single-use injection. Since the doses of epinephrine delivered from EpiPen or EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
## Off-Label Use and Dosage (Pediatric)
### Guideline-Supported Use
There is limited information regarding Off-Label Guideline-Supported Use of EpiPen in pediatric patients.
### Non–Guideline-Supported Use
- Aerosolized levo-epinephrine (1:1000) is at least as effective as racemic epinephrine (2.25%) in the treatment of laryngotracheitis in children (6 months to 6 years of age) with moderate to severe croup.[5]
- Subcutaneous epinephrine is effective in the treatment of acute wheezing in children less than 2 years of age.[6]
# Contraindications
- None
# Warnings
### Precautions
- Emergency Treatment
- EpiPen and EpiPen Jr are intended for immediate administration as emergency supportive therapy and are not intended as a substitute for immediate medical care. In conjunction with the administration of epinephrine, the patient should seek immediate medical or hospital care. More than two sequential doses of epinephrine should only be administered under direct medical supervision.
- Incorrect Locations of Injection
- EpiPen and EpiPen Jr should only be injected into the anterolateral aspect of the thigh [see Dosage and Administration (2) and Patient Counseling Information (17)].
Do not inject intravenously. Large doses or accidental intravenous injection of epinephrine may result in cerebral hemorrhage due to sharp rise in blood pressure. Rapidly acting vasodilators can counteract the marked pressor effects of epinephrine if there is such inadvertent administration.
Do not inject into buttock. Injection into the buttock may not provide effective treatment of anaphylaxis. Advise the patient to go immediately to the nearest emergency room for further treatment of anaphylaxis. Additionally, injection into the buttock has been associated with gas gangrene. Cleansing with alcohol does not kill bacterial spores, and therefore, does not lower this risk.
Do not inject into digits, hands or feet. Since epinephrine is a strong vasoconstrictor, accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area. Advise the patient to go immediately to the nearest emergency room and to inform the healthcare provider in the emergency room of the location of the accidental injection. Treatment of such inadvertent administration should consist of vasodilation, in addition to further appropriate treatment of anaphylaxis [ see Adverse Reactions (6)].
- Do not inject intravenously. Large doses or accidental intravenous injection of epinephrine may result in cerebral hemorrhage due to sharp rise in blood pressure. Rapidly acting vasodilators can counteract the marked pressor effects of epinephrine if there is such inadvertent administration.
- Do not inject into buttock. Injection into the buttock may not provide effective treatment of anaphylaxis. Advise the patient to go immediately to the nearest emergency room for further treatment of anaphylaxis. Additionally, injection into the buttock has been associated with gas gangrene. Cleansing with alcohol does not kill bacterial spores, and therefore, does not lower this risk.
- Do not inject into digits, hands or feet. Since epinephrine is a strong vasoconstrictor, accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area. Advise the patient to go immediately to the nearest emergency room and to inform the healthcare provider in the emergency room of the location of the accidental injection. Treatment of such inadvertent administration should consist of vasodilation, in addition to further appropriate treatment of anaphylaxis [ see Adverse Reactions (6)].
- Allergic Reactions Associated With Sulfite
- The presence of a sulfite in this product should not deter administration of the drug for treatment of serious allergic or other emergency situations even if the patient is sulfite-sensitive.
- Epinephrine is the preferred treatment for serious allergic reactions or other emergency situations even though this product contains sodium metabisulfite, a sulfite that may, in other products, cause allergic-type reactions including anaphylactic symptoms or life-threatening or less severe asthmatic episodes in certain susceptible persons.
- The alternatives to using epinephrine in a life-threatening situation may not be satisfactory.
- Disease Interactions
- Some patients may be at greater risk for developing adverse reactions after epinephrine administration. Despite these concerns, it should be recognized that the presence of these conditions is not a contraindication to epinephrine administration in an acute, life-threatening situation. Therefore, patients with these conditions, and/or any other person who might be in a position to administer EpiPen or EpiPen Jr to a patient experiencing anaphylaxis should be carefully instructed in regard to the circumstances under which epinephrine should be used.
- Patients with Heart Disease
- Epinephrine should be administered with caution to patients who have heart disease, including patients with cardiac arrhythmias, coronary artery or organic heart disease, or hypertension. In such patients, or in patients who are on drugs that may sensitize the heart to arrhythmias, epinephrine may precipitate or aggravate angina pectoris as well as produce ventricular arrhythmias.
- Other Patients and Diseases
- Epinephrine should be administered with caution to patients with hyperthyroidism, diabetes, elderly individuals, and pregnant women. Patients with Parkinson’s disease may notice a temporary worsening of symptoms.
# Adverse Reactions
## Clinical Trials Experience
- Due to the lack of randomized, controlled clinical trials of epinephrine for the treatment of anaphylaxis, the true incidence of adverse reactions associated with the systemic use of epinephrine is difficult to determine. Adverse reactions reported in observational trials, case reports, and studies are listed below.
- Common adverse reactions to systemically administered epinephrine include anxiety; apprehensiveness; restlessness; tremor; weakness; dizziness; sweating; palpitations; pallor; nausea and vomiting; headache; and/or respiratory difficulties. These symptoms occur in some persons receiving therapeutic doses of epinephrine, but are more likely to occur in patients with hypertension or hyperthyroidism [see Warnings and Precautions (5.4)].
- Arrhythmias, including fatal ventricular fibrillation, have been reported, particularly in patients with underlying cardiac disease or those receiving certain drugs [see Warnings and Precautions (5.4) and Drug Interactions (7)].
- Rapid rises in blood pressure have produced cerebral hemorrhage, particularly in elderly patients with cardiovascular disease [see Warnings and Precautions (5.4)].
- Angina may occur in patients with coronary artery disease [see Warnings and Precautions (5.4)].
- Accidental injection into the digits, hands or feet may result in loss of blood flow to the affected area [see Warnings and Precautions (5.2)].
- Adverse events experienced as a result of accidental injections may include increased heart rate, local reactions including injection site pallor, coldness and hypoesthesia or injury at the injection site resulting in bruising, bleeding, discoloration, erythema or skeletal injury.
- Injection into the buttock has resulted in cases of gas gangrene.
## Postmarketing Experience
There is limited information regarding Postmarketing Experience of EpiPen in the drug label.
# Drug Interactions
- Patients who receive epinephrine while concomitantly taking cardiac glycosides, diuretics, or anti-arrhythmics should be observed carefully for the development of cardiac arrhythmias [see Warnings and Precautions (5.4)].
- The effects of epinephrine may be potentiated by tricyclic antidepressants, monoamine oxidase inhibitors, levothyroxine sodium, and certain antihistamines, notably chlorpheniramine, tripelennamine, and diphenhydramine.
- The cardiostimulating and bronchodilating effects of epinephrine are antagonized by beta- adrenergic blocking drugs, such as propranolol.
- The vasoconstricting and hypertensive effects of epinephrine are antagonized by alpha- adrenergic blocking drugs, such as phentolamine.
- Ergot alkaloids may also reverse the pressor effects of epinephrine.
# Use in Specific Populations
### Pregnancy
Pregnancy Category (FDA):
- Pregnancy Category C
- There are no adequate and well controlled studies of the acute effect of epinephrine in pregnant women.
- Epinephrine was teratogenic in rabbits, mice and hamsters. Epinephrine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus (fetal anoxia, spontaneous abortion, or both).
- Epinephrine has been shown to have teratogenic effects when administered subcutaneously in rabbits at approximately 30 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal dose of 1.2 mg/kg/day for two to three days), in mice at approximately 7 times the maximum daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal subcutaneous dose of 1 mg/kg/day for 10 days), and in hamsters at approximately 5 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a maternal subcutaneous dose of 0.5 mg/kg/day for 4 days).
- These effects were not seen in mice at approximately 3 times the maximum recommended daily subcutaneous or intramuscular dose (on a mg/m2 basis at a subcutaneous maternal dose of 0.5 mg/kg/day for 10 days).
Pregnancy Category (AUS):
- Australian Drug Evaluation Committee (ADEC) Pregnancy Category
There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of EpiPen in women who are pregnant.
### Labor and Delivery
There is no FDA guidance on use of EpiPen during labor and delivery.
### Nursing Mothers
- It is not known whether epinephrine is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when EpiPen is administered to a nursing woman.
### Pediatric Use
- EpiPen or EpiPen Jr may be administered to pediatric patients at a dosage appropriate to body weight. Clinical experience with the use of epinephrine suggests that the adverse reactions seen in children are similar in nature and extent to those both expected and reported in adults. Since the doses of epinephrine delivered from EpiPen and EpiPen Jr are fixed, consider using other forms of injectable epinephrine if doses lower than 0.15 mg are deemed necessary.
### Geriatic Use
- Clinical studies for the treatment of anaphylaxis have not been performed in subjects aged 65 and over to determine whether they respond differently from younger subjects. However, other reported clinical experience with use of epinephrine for the treatment of anaphylaxis has identified that geriatric patients may be particularly sensitive to the effects of epinephrine. Therefore, EpiPen should be administered with caution in elderly individuals, who may be at greater risk for developing adverse reactions after epinephrine administration.
### Gender
There is no FDA guidance on the use of EpiPen with respect to specific gender populations.
### Race
There is no FDA guidance on the use of EpiPen with respect to specific racial populations.
### Renal Impairment
There is no FDA guidance on the use of EpiPen in patients with renal impairment.
### Hepatic Impairment
There is no FDA guidance on the use of EpiPen in patients with hepatic impairment.
### Females of Reproductive Potential and Males
There is no FDA guidance on the use of EpiPen in women of reproductive potentials and males.
### Immunocompromised Patients
There is no FDA guidance one the use of EpiPen in patients who are immunocompromised.
# Administration and Monitoring
### Administration
- Intramuscular
### Monitoring
There is limited information regarding Monitoring of EpiPen in the drug label.
# IV Compatibility
There is limited information regarding IV Compatibility of EpiPen in the drug label.
# Overdosage
## Acute Overdose
### Signs and Symptoms
- Overdosage of epinephrine may produce extremely elevated arterial pressure, which may result in cerebrovascular hemorrhage, particularly in elderly patients. Overdosage may also result in pulmonary edema because of peripheral vascular constriction together with cardiac stimulation. Treatment consists of rapidly acting vasodilators or alpha-adrenergic blocking drugs and/or respiratory support.
- Epinephrine overdosage can also cause transient bradycardia followed by tachycardia, and these may be accompanied by potentially fatal cardiac arrhythmias. Premature ventricular contractions may appear within one minute after injection and may be followed by multifocal ventricular tachycardia (prefibrillation rhythm). Subsidence of the ventricular effects may be followed by atrial tachycardia and occasionally by atrioventricular block. Treatment of arrhythmias consists of administration of a beta-adrenergic blocking drug such as propranolol.
- Overdosage sometimes results in extreme pallor and coldness of the skin, metabolic acidosis, and kidney failure.
### Management
- Suitable corrective measures must be taken in such situations.
## Chronic Overdose
There is limited information regarding Chronic Overdose of EpiPen in the drug label.
# Pharmacology
## Mechanism of Action
- Epinephrine acts on both alpha- and beta-adrenergic receptors.
## Structure
- EpiPen (epinephrine injection, USP) 0.3 mg and EpiPen Jr (epinephrine injection, USP) 0.15 mg are auto-injectors and combination products containing drug and device components.
- Each EpiPen Auto-Injector, 0.3 mg delivers a single dose of 0.3 mg epinephrine from epinephrine injection, USP 1:1000 (0.3 mL) in a sterile solution.
- Each EpiPen Jr Auto-Injector, 0.15 mg delivers a single dose of 0.15 mg epinephrine from epinephrine injection, USP 1:2000 (0.3 mL) in a sterile solution.
- The EpiPen and EpiPen Jr each contain 2 mL epinephrine solution. Approximately 1.7 mL remains in the auto-injector after activation, but is not available for future use, and should be discarded.
- Each 0.3 mL in the EpiPen Auto-Injector contains 0.3 mg epinephrine, 1.8 mg sodium chloride, 0.5 mg sodium metabisulfite, hydrochloric acid to adjust pH, and Water for Injection. The pH range is 2.2–5.0.
- Each 0.3 mL in the EpiPen Jr Auto-Injector contains 0.15 mg epinephrine, 1.8 mg sodium chloride, 0.5 mg sodium metabisulfite, hydrochloric acid to adjust pH, and Water for Injection. The pH range is 2.2-5.0.
- Epinephrine is a sympathomimetic catecholamine. Chemically, epinephrine is (-)-3,4- Dihydroxy-α-[(methylamino)methyl]benzyl alcohol with the following structure:
- Epinephrine solution deteriorates rapidly on exposure to air or light, turning pink from oxidation to adrenochrome and brown from the formation of melanin. Replace EpiPen and EpiPen Jr if the epinephrine solution appears discolored (pinkish or brown color), cloudy, or contains particles.
- Thoroughly review the patient instructions and operation of EpiPen or EpiPen Jr with patients and caregivers prior to use.
## Pharmacodynamics
- Through its action on alpha-adrenergic receptors, epinephrine lessens the vasodilation and increased vascular permeability that occurs during anaphylaxis, which can lead to loss of intravascular fluid volume and hypotension.
- Through its action on beta-adrenergic receptors, epinephrine causes bronchial smooth muscle relaxation and helps alleviate bronchospasm, wheezing and dyspnea that may occur during anaphylaxis.
- Epinephrine also alleviates pruritus, urticaria, and angioedema and may relieve gastrointestinal and genitourinary symptoms associated with anaphylaxis because of its relaxer effects on the smooth muscle of the stomach, intestine, uterus and urinary bladder.
- When given subcutaneously or intramuscularly, epinephrine has a rapid onset and short duration of action.
## Pharmacokinetics
There is limited information regarding Pharmacokinetics of EpiPen in the drug label.
## Nonclinical Toxicology
- Long-term studies to evaluate the carcinogenic potential of epinephrine have not been conducted.
- Epinephrine and other catecholamines have been shown to have mutagenic potential in vitro and to be an oxidative mutagen in a WP2 bacterial reverse mutation assay.
- Epinephrine was positive in the DNA Repair test with B. subtilis (REC) assay, but was not mutagenic in the Salmonella bacterial reverse mutation assay.
- The potential for epinephrine to impair fertility has not been evaluated.
# Clinical Studies
There is limited information regarding Clinical Studies of EpiPen in the drug label.
# How Supplied
- EpiPen Auto-Injectors (epinephrine injections, USP, 1:1000, 0.3 mL) are available as EpiPen 2-Pak®, NDC 49502-500-02, a pack that contains two EpiPen Auto-Injectors (epinephrine injections, USP, 1:1000, 0.3 mL) and one EpiPen Auto-Injector trainer device.
- EpiPen Jr Auto-Injectors (epinephrine injections, USP, 1:2000, 0.3 mL) are available as EpiPen Jr 2-Pak®, NDC 49502-501-02, a pack that contains two EpiPen Jr Auto-Injectors (epinephrine injections, USP, 1:2000, 0.3 mL) and one EpiPen Auto-Injector trainer device.
- EpiPen 2-Pak® and EpiPen Jr 2-Pak® also includes an S-clip to clip two carrier tubes together.
- Storage and Handling
- Protect from light. Epinephrine is light sensitive and should be stored in the carrier tube provided to protect it from light. Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) (See USP Controlled Room Temperature). Do not refrigerate. Before using, check to make sure the solution in the auto-injector is clear and colorless. Replace the auto-injector if the solution is discolored (pinkish or brown color), cloudy, or contains particles.
## Storage
There is limited information regarding EpiPen Storage in the drug label.
# Images
## Drug Images
## Package and Label Display Panel
# Patient Counseling Information
- A healthcare provider should review the patient instructions and operation of EpiPen and EpiPen Jr in detail, with the patient or caregiver.
- Epinephrine is essential for the treatment of anaphylaxis. Patients who are at risk of or with a history of severe allergic reactions (anaphylaxis) to insect stings or bites, foods, drugs, and other allergens, as well as idiopathic and exercise-induced anaphylaxis, should be carefully instructed about the circumstances under which epinephrine should be used.
- Administration and Training
- Patients and/or caregivers should be instructed in the appropriate use of EpiPen and EpiPen Jr. EpiPen should be injected into the middle of the outer thigh (through clothing, if necessary). Each device is a single-use injection. Advise patients to seek immediate medical care in conjunction with administration of EpiPen.
- Complete patient information, including dosage, directions for proper administration and precautions can be found inside each EpiPen or EpiPen Jr carton. A printed label on the surface of EpiPen shows instructions for use and a diagram depicting the injection process.
- Patients and/or caregivers should be instructed to use the Trainer to familiarize themselves with the use of EpiPen in an allergic emergency. The Trainer may be used multiple times. A Trainer device is provided in 2-Pak cartons.
- Adverse Reactions
- Epinephrine may produce symptoms and signs that include an increase in heart rate, the sensation of a more forceful heartbeat, palpitations, sweating, nausea and vomiting, difficulty breathing, pallor, dizziness, weakness or shakiness, headache, apprehension, nervousness, or anxiety. These signs and symptoms usually subside rapidly, especially with rest, quiet and recumbency. Patients with hypertension or hyperthyroidism may develop more severe or persistent effects, and patients with coronary artery disease could experience angina. Patients with diabetes may develop increased blood glucose levels following epinephrine administration. Patients with Parkinson’s disease may notice a temporary worsening of symptoms.
- Accidental Injection
- Advise patients to seek immediate medical care in the case of accidental injection. Since epinephrine is a strong vasoconstrictor when injected into the digits, hands, or feet, treatment should be directed at vasodilatation if there is such an accidental injection to these areas.
- Storage and Handling
- Instruct patients to inspect the epinephrine solution visually through the clear window of the auto-injector periodically. EpiPen and EpiPen Jr should be replaced if the epinephrine solution appears discolored (pinkish or brown color), cloudy, or contains particles. Epinephrine is light sensitive and should be stored in the carrier tube provided to protect it from light. The carrier tube is not waterproof. Patients should be instructed that EpiPen and EpiPen Jr must be used or properly disposed once the blue safety release is removed or after use.
# Precautions with Alcohol
- Alcohol-EpiPen interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
# Brand Names
- EpiPen®[7]
# Look-Alike Drug Names
- EPINEPHrine® — ePHEDrine®[8]
# Drug Shortage Status
# Price | https://www.wikidoc.org/index.php/Epi-Pen | |
dc507449fd36afcd404a20fc6130143b58bc8f98 | wikidoc | Epimer | Epimer
In chemistry, an epimer is a stereoisomer of another compound that has a different configuration at only one of several stereogenic centers. Stereoisomers include enantiomers and diastereomers, both which contain a stereogenic center (excluding geometric isomers, which is a class of diastereomers).
For example, the sugars α-glucose and β-glucose are epimers. In α-glucose, the -OH group on the first (anomeric) carbon is in the direction opposite the methylene group. In β-glucose, the -OH group is oriented in the same direction as the methylene group . These two molecules are both epimers and anomers.
In this case β-D-glucopyranose and β-D-mannopyranose are epimers because the differ only in the stereochemistry at the 2 position. The hydroxyl group in β-D-glucopyranose is equatorial (in the "plane" of the ring) while in β-D-mannopyranose the 2 hydroxyl group is axial (up from the "plane" of the ring). These two molecules are epimers but not anomers.
In chemical nomenclature one of the epimeric pairs is given the prefix epi- for example in quinine and epi-quinine. When the pairs are enantiomers the prefix becomes ent-. | Epimer
In chemistry, an epimer is a stereoisomer of another compound that has a different configuration at only one of several stereogenic centers. Stereoisomers include enantiomers and diastereomers, both which contain a stereogenic center (excluding geometric isomers, which is a class of diastereomers).
For example, the sugars α-glucose and β-glucose are epimers. In α-glucose, the -OH group on the first (anomeric) carbon is in the direction opposite the methylene group. In β-glucose, the -OH group is oriented in the same direction as the methylene group [1]. These two molecules are both epimers and anomers.
In this case β-D-glucopyranose and β-D-mannopyranose are epimers because the differ only in the stereochemistry at the 2 position. The hydroxyl group in β-D-glucopyranose is equatorial (in the "plane" of the ring) while in β-D-mannopyranose the 2 hydroxyl group is axial (up from the "plane" of the ring). These two molecules are epimers but not anomers.
In chemical nomenclature one of the epimeric pairs is given the prefix epi- for example in quinine and epi-quinine. When the pairs are enantiomers the prefix becomes ent-. | https://www.wikidoc.org/index.php/Epimer | |
1bb53bfc441704c56e5861b788a80c1fab715dac | wikidoc | Ergine | Ergine
LSA, also known as d-lysergic acid amide, d-lysergamide, ergine, and LA-111, is an alkaloid of the ergoline family that occurs in various species of vines of the Convolvulaceae and some species of fungi. As the dominant alkaloid in the hallucinogenic seeds of Rivea corymbosa (ololiuhqui), Argyreia nervosa (Hawaiian baby woodrose) and Ipomoea tricolor (morning glories, tlitliltzin), it is often stated that ergine and/or isoergine (its epimer) is responsible for the psychedelic activity. In fact, the effects of synthetic LSA and iso-LSA are not particularly psychedelic, see Mixing the Kykeon below for a summary of human trials, and Chapter 17 and entry #26 of TiHKAL for further discussion. As a precursor to LSD, ergine is a DEA schedule III drug in the United States.
# History
A traditional use of morning glory seeds by Mexican Native Americans was first described by Richard Schultes in 1941 in a short report documenting their use going back to Aztec times (cited in TiHKAL by Alexander Shulgin). Further research was published in 1960, when Don Thomes MacDougall reported that the seeds of Ipomoea tricolor were used as sacraments by certain Zapotecs, sometimes in conjunction with the seeds of Rivea corymbosa, another species which has a similar chemical composition, with lysergol instead of ergometrine. Ergine was assayed for human activity by Albert Hofmann in self-trials in 1947, well before it was known to be a natural compound. Intramuscular administration of a 500 microgram dose led to a tired, dreamy state, with an inability to maintain clear thoughts. After a short period of sleep the effects were gone, and normal baseline was recovered within five hours. .
# Natural occurrence
Ergine has been found in high concentrations of 20 mg/kg dry weight in the grass Stipa robusta (sleepygrass) infected with an Acremonium endophytic fungus together with other ergot alkaloids
# Extraction
LSA can be extracted from morning glory seeds or Hawaiian baby woodrose. | Ergine
LSA, also known as d-lysergic acid amide, d-lysergamide, ergine, and LA-111, is an alkaloid of the ergoline family that occurs in various species of vines of the Convolvulaceae and some species of fungi. As the dominant alkaloid in the hallucinogenic seeds of Rivea corymbosa (ololiuhqui), Argyreia nervosa (Hawaiian baby woodrose) and Ipomoea tricolor (morning glories, tlitliltzin), it is often stated that ergine and/or isoergine (its epimer) is responsible for the psychedelic activity. In fact, the effects of synthetic LSA and iso-LSA are not particularly psychedelic, see Mixing the Kykeon below for a summary of human trials, and Chapter 17 and entry #26 of TiHKAL for further discussion. As a precursor to LSD, ergine is a DEA schedule III drug in the United States.
# History
A traditional use of morning glory seeds by Mexican Native Americans was first described by Richard Schultes in 1941 in a short report documenting their use going back to Aztec times (cited in TiHKAL by Alexander Shulgin). Further research was published in 1960, when Don Thomes MacDougall reported that the seeds of Ipomoea tricolor were used as sacraments by certain Zapotecs, sometimes in conjunction with the seeds of Rivea corymbosa, another species which has a similar chemical composition, with lysergol instead of ergometrine. Ergine was assayed for human activity by Albert Hofmann in self-trials in 1947, well before it was known to be a natural compound. Intramuscular administration of a 500 microgram dose led to a tired, dreamy state, with an inability to maintain clear thoughts. After a short period of sleep the effects were gone, and normal baseline was recovered within five hours.[2] .
# Natural occurrence
Ergine has been found in high concentrations of 20 mg/kg dry weight in the grass Stipa robusta (sleepygrass) infected with an Acremonium endophytic fungus together with other ergot alkaloids
[3].
# Extraction
LSA can be extracted from morning glory seeds[4] or Hawaiian baby woodrose[5]. | https://www.wikidoc.org/index.php/Ergine | |
8454453410584ce83d981130343b6a9b77fc2a93 | wikidoc | Eschar | Eschar
From the Greek word eschara (scab) an eschar (Template:IPAEng) is a piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections and late exposure to anthrax. Eschar is sometimes called a "black wound" because the wound is covered with thick, dry, black necrotic tissue.
Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted).
If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy, or surgical incision through the eschar, may be indicated.
An escharotic is a substance that causes tissue to die and slough off. Examples include acids, alkalines, carbon dioxide, metallic salts, or electric cautery. | Eschar
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
From the Greek word eschara (scab) an eschar (Template:IPAEng) is a piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections and late exposure to anthrax. Eschar is sometimes called a "black wound" because the wound is covered with thick, dry, black necrotic tissue.
Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted).
If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy, or surgical incision through the eschar, may be indicated.
An escharotic is a substance that causes tissue to die and slough off. Examples include acids, alkalines, carbon dioxide, metallic salts, or electric cautery.
# External links
- http://www.medbc.com/annals/review/vol_3/num_2/text/vol3n2p79.htm
Template:Disease-stub | https://www.wikidoc.org/index.php/Eschar | |
88bd643c23606c695b024c85d405556e4b6fe65e | wikidoc | Essiac | Essiac
# Overview
Essiac or Essiac Tea is a blend of herbs used to make a tea that is believed by some and questioned by others to have cancer-treating properties. It was discovered by a Canadian nurse, Rene Caisse, who named it after her last name spelled backwards. The original formula is believed to have its roots in native Canadian Ojibwa medicine and contains greater burdock root (Arctium lappa), slippery elm inner bark (Ulmus rubra, formerly known as Ulmus fulva), sheep sorrel (Rumex acetosella), and Indian or Turkish rhubarb root (Rheum officinale).
# Effectiveness
With respect to the use of Essiac in treating cancer, the U.S. National Institutes of Health's Medline states that as of early 2008:
Currently, there is not enough evidence to recommend for or against the use of this herbal mixture as a therapy for any type of cancer. Different brands may contain variable ingredients, and the comparative effectiveness of these formulas is not known. None of the individual herbs used in Essiac has been tested in rigorous human cancer trials (rhubarb has shown some anti-tumor properties in animal experiments; slippery elm inner bark has not; sheep sorrel and burdock have been used traditionally in cancer remedies). Numerous individual patient testimonials and reports from manufacturers are available on the Internet, although these cannot be considered scientifically viable as evidence. Individuals with cancer are advised not to delay treatment with more proven therapies.
# History
Caisse set up a free clinic in Bracebridge, Ontario which ran from 1934 to 1942. During that time a number of petitions were presented to the Legislature in Ontario, in 1938 calling for Rene to be allowed to practice throughout Ontario, but such permission was not granted.
Medline notes there are more than 40 different essiac-like products now being sold in North America, Europe, and Australia. One of these alternative preparations contains eight herbs, adding red clover (Trifolium pratense), watercress (Nasturtium officinale), blessed thistle (Cnicus benedictus), and kelp (Laminaria digitata) to the original four ingredients. Other preparations add echinacea and black walnut (Juglans nigra) or other ingredients, such as cat's claw ( Uncaria tomentosa ).
According to Medline, based on tradition, some people take essiac tea on occasion for general health purposes, detoxification, or for healing of various ailments other than cancer. Some of these other ailments include AIDS, asthma, chronic fatigue syndrome, diabetes, immune system disorders, liver problems, Lyme disease, and lupus erythematosus. NIH's Medline says even less evidence is available for these applications than for cancer.
Updating the history of Essiac, Medline says:
In the 1970s, Caisse provided the formula to Resperin Corporation Ltd., with the understanding that Resperin would coordinate a scientific trial in humans. Although a study was initiated, it was stopped early amidst questions of improper preparation of the formula and inadequate study design. This research was never completed. Resperin Corporation Ltd., which owned the Essiac name, formally went out of business after transferring rights to the Essiac name and selling the secret formula to Essiac Products Ltd., which currently distributes products through Essiac International. | Essiac
# Overview
Essiac or Essiac Tea is a blend of herbs used to make a tea that is believed[1] by some and questioned by others[2] to have cancer-treating properties. It was discovered by a Canadian nurse, Rene Caisse, who named it after her last name spelled backwards. The original formula is believed to have its roots in native Canadian Ojibwa medicine and contains greater burdock root (Arctium lappa), slippery elm inner bark (Ulmus rubra, formerly known as Ulmus fulva), sheep sorrel (Rumex acetosella), and Indian or Turkish rhubarb root (Rheum officinale).[3]
# Effectiveness
With respect to the use of Essiac in treating cancer, the U.S. National Institutes of Health's Medline states that as of early 2008:
Currently, there is not enough evidence to recommend for or against the use of this herbal mixture as a therapy for any type of cancer. Different brands may contain variable ingredients, and the comparative effectiveness of these formulas is not known. None of the individual herbs used in Essiac has been tested in rigorous human cancer trials (rhubarb has shown some anti-tumor properties in animal experiments; slippery elm inner bark has not; sheep sorrel and burdock have been used traditionally in cancer remedies). Numerous individual patient testimonials and reports from manufacturers are available on the Internet, although these cannot be considered scientifically viable as evidence. Individuals with cancer are advised not to delay treatment with more proven therapies.[4]
# History
Caisse set up a free clinic in Bracebridge, Ontario which ran from 1934 to 1942. During that time a number of petitions were presented to the Legislature in Ontario, in 1938 calling for Rene to be allowed to practice throughout Ontario, but such permission was not granted.
Medline notes there are more than 40 different essiac-like products now being sold in North America, Europe, and Australia. One of these alternative preparations contains eight herbs, adding red clover (Trifolium pratense), watercress (Nasturtium officinale), blessed thistle (Cnicus benedictus), and kelp (Laminaria digitata) to the original four ingredients. Other preparations add echinacea and black walnut (Juglans nigra) or other ingredients, such as cat's claw ( Uncaria tomentosa ).[5]
According to Medline, based on tradition, some people take essiac tea on occasion for general health purposes, detoxification, or for healing of various ailments other than cancer. Some of these other ailments include AIDS, asthma, chronic fatigue syndrome, diabetes, immune system disorders, liver problems, Lyme disease, and lupus erythematosus. NIH's Medline says even less evidence is available for these applications than for cancer.[6]
Updating the history of Essiac, Medline says:
In the 1970s, Caisse provided the formula to Resperin Corporation Ltd., with the understanding that Resperin would coordinate a scientific trial in humans. Although a study was initiated, it was stopped early amidst questions of improper preparation of the formula and inadequate study design. This research was never completed. Resperin Corporation Ltd., which owned the Essiac name, formally went out of business after transferring rights to the Essiac name and selling the secret formula to Essiac Products Ltd., which currently distributes products through Essiac International. | https://www.wikidoc.org/index.php/Essiac | |
200d41b0c543e1002bf575394d08a8a14b5708ed | wikidoc | Eutony | Eutony
Eutony is a mind-body discipline created by Gerda Alexander based upon the experience of one's own body. It develops the ability to be aware and able to regulate muscular tone, adapting it to any life situation. The term eutony comes from Greek Eu: good, - and of Latin Tonus: tension, the grade of tension or elasticity of muscle fibers. It was coined to express the idea of a harmoniously balanced "tonicity in constant adaptation to the state or activity of the moment".
# Eutony and muscular tone
Eutony uses the knowledge of one's own body as a way to develop an appropriate use of its structures and the possibility of flowing among levels of good tension (i. e., the appropriate level to face every-day activities). There is a component of the muscular tension of which most people are not conscious.
"Good" muscular tone, characteristic of the eutonic state, provides flexibility and adaptability. On the contrary, to be "distonic" means either to remain in a state of excessive tension (hiper-tone), or feeling heavy or without force (hipo-tone), or the impossibility of fluctuating outside of a normo-tone in diverse situations.
# Origins of Eutony
Eutony is a discipline developed from the personal experience and initiative of Gerda Alexander. As a young woman, she contracted rheumatic fever and endocarditis, suffering several crisis. This forced her precociously to create movement forms that did not complicate their affections. Long periods of rest stimulated her to investigate on herself looking for a "more economic" and more spontaneous movement form, starting from the learning of the tonic regulation to achieve further well-being. Gerda postulated that it is "necessary to learn a little more every day about what we are that body in which we can lean on". By means of the observation and reflection on their students, their own ailments and difficulties in mobility, and the investigation on the neuro-psychological basements of the human being's movements, she molded her own method.
At the beginning, Gerda Alexander's personal search in the area of the performing-arts had the premise of achieving the possibility to be able to expres without preset models to interfere in the functional and creative possibilities. In that time this intention was denominated: "the search of the spontaneous movement". Gerda spent approximately 30 years in this resarch, until summing up what she would later call Eutony.
# Practice of Eutony
The transmission of Eutony takes place in group classes or individual sessions. The eutonist accompanies the student in the recognition process and personal exploration without to interfere neither to influence it, allowing the development of its own potentialities.
An Eutony session begins with a phase of "inventory" in which the student, through a series of "control positions" becomes aware of his/her initial state of muscular tone. Then by a means of physical activities guided by the eutonist, which may include the use of objects (balls, sticks, pillows) or the contact between the eutonist and the student, the latter gains awareness of different "principles" (see below). At the end of the class or session the student may be asked to repeat the control positions initially used to check the differences in both his/her states and awareness of them.
Eutony leads to a better self-understanding increasing cognitives and emotional capacities, harmony and the possibility of being attentive.
By developing the capacity to observe oneself, accepting what happens without judging, the individual transforms into a witness of his/her own actions and life. Turning into a sharper, non judging observer, allows him/her to achieve deeper knowledge of both oneself and the others.
# Principles of Eutony
In Eutony the word "principle" has a particular meaning. The principles constitute methodological tools to be used in the classes or sessions that facilitate the student to recover the fluctuation of tone.
Such principles are:
- awareness of the skin
- awareness of the internal body space
- awareness of the bones
- conscious contact
- experience of transport (conscious straightening reflex)
- "repousser" (to reject-to push)
- active and passive movements
- micro-movements (movements of decompression of the articulations)
- control positions (sequences of movements that allow to evaluate the state of muscular flexibility)
- eutonic movement
- vibrations (vocie and bones)
# Other Uses
Eutony is an uncommon noun which means pleasantness of sound of word.
# Further reading
- Alexander, Gerda (1981). Eutony; The holistic discovery of the total person. New York: Felix Morrow..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
- Vishnivetz, Berta (1994). Eutonía; La Educación del Cuerpo hacia el Ser. Buenos Aires / Madrid: Paidós.
- Odessky, Alejandro (2002). Eutonía y stress. Buenos Aires: Lugar Editorial. 950-892-164-1. | Eutony
Template:Mind-body interventions
Eutony is a mind-body discipline created by Gerda Alexander based upon the experience of one's own body. It develops the ability to be aware and able to regulate muscular tone, adapting it to any life situation. The term eutony comes from Greek Eu: good, - and of Latin Tonus: tension, the grade of tension or elasticity of muscle fibers. It was coined to express the idea of a harmoniously balanced "tonicity in constant adaptation to the state or activity of the moment".
# Eutony and muscular tone
Eutony uses the knowledge of one's own body as a way to develop an appropriate use of its structures and the possibility of flowing among levels of good tension (i. e., the appropriate level to face every-day activities). There is a component of the muscular tension of which most people are not conscious.
"Good" muscular tone, characteristic of the eutonic state, provides flexibility and adaptability. On the contrary, to be "distonic" means either to remain in a state of excessive tension (hiper-tone), or feeling heavy or without force (hipo-tone), or the impossibility of fluctuating outside of a normo-tone in diverse situations.
# Origins of Eutony
Eutony is a discipline developed from the personal experience and initiative of Gerda Alexander. As a young woman, she contracted rheumatic fever and endocarditis, suffering several crisis. This forced her precociously to create movement forms that did not complicate their affections. Long periods of rest stimulated her to investigate on herself looking for a "more economic" and more spontaneous movement form, starting from the learning of the tonic regulation to achieve further well-being. Gerda postulated that it is "necessary to learn a little more every day about what we are that body in which we can lean on". By means of the observation and reflection on their students, their own ailments and difficulties in mobility, and the investigation on the neuro-psychological basements of the human being's movements, she molded her own method.
At the beginning, Gerda Alexander's personal search in the area of the performing-arts had the premise of achieving the possibility to be able to expres without preset models to interfere in the functional and creative possibilities. In that time this intention was denominated: "the search of the spontaneous movement". Gerda spent approximately 30 years in this resarch, until summing up what she would later call Eutony.
# Practice of Eutony
The transmission of Eutony takes place in group classes or individual sessions. The eutonist accompanies the student in the recognition process and personal exploration without to interfere neither to influence it, allowing the development of its own potentialities.
An Eutony session begins with a phase of "inventory" in which the student, through a series of "control positions" becomes aware of his/her initial state of muscular tone. Then by a means of physical activities guided by the eutonist, which may include the use of objects (balls, sticks, pillows) or the contact between the eutonist and the student, the latter gains awareness of different "principles" (see below). At the end of the class or session the student may be asked to repeat the control positions initially used to check the differences in both his/her states and awareness of them.
Eutony leads to a better self-understanding increasing cognitives and emotional capacities, harmony and the possibility of being attentive.
By developing the capacity to observe oneself, accepting what happens without judging, the individual transforms into a witness of his/her own actions and life. Turning into a sharper, non judging observer, allows him/her to achieve deeper knowledge of both oneself and the others.
# Principles of Eutony
In Eutony the word "principle" has a particular meaning. The principles constitute methodological tools to be used in the classes or sessions that facilitate the student to recover the fluctuation of tone.
Such principles are:
- awareness of the skin
- awareness of the internal body space
- awareness of the bones
- conscious contact
- experience of transport (conscious straightening reflex)
- "repousser" (to reject-to push)
- active and passive movements
- micro-movements (movements of decompression of the articulations)
- control positions (sequences of movements that allow to evaluate the state of muscular flexibility)
- eutonic movement
- vibrations (vocie and bones)
# Other Uses
Eutony is an uncommon noun which means pleasantness of sound of word.[1]
# Further reading
- Alexander, Gerda (1981). Eutony; The holistic discovery of the total person. New York: Felix Morrow..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
- Vishnivetz, Berta (1994). Eutonía; La Educación del Cuerpo hacia el Ser. Buenos Aires / Madrid: Paidós.
- Odessky, Alejandro (2002). Eutonía y stress. Buenos Aires: Lugar Editorial. 950-892-164-1. | https://www.wikidoc.org/index.php/Eutony | |
ecc70457ba51176a8184a1c681629dd28142254d | wikidoc | Eyelid | Eyelid
# Overview
An eyelid is a thin fold of skin that covers and protects an eye. With the exception of the prepuce and the labia minora, it has the thinnest skin of the whole body. The levator palpebrae superioris muscle retracts the eyelid to "open" the eye. This can be either voluntarily or involuntarily. The human eyelid features a row of eyelashes which serve to heighten the protection of the eye from dust and foreign debris. "Palpebral" (and "blepharo") means relating to the eyelids.
# Anatomy
## Layers
In the human eyelid, there are various layers; from superficial to deep, they are:
skin, subcutaneous tissue, orbicularis oculi, orbital septum & tarsal plates, and palpebral conjunctiva. The meibomian glands lie within the eyelid and secrete the lipid part of the tearfilm.
### Skin
The skin is similar to areas elsewhere, but have more pigment cells. In diseased persons these may wander and cause a discoloration of the lids. It contains sweat glands and hairs, the latter becoming eyelashes as the border of the eyelid is met.
## Innervation
In humans, the sensory nerve supply to the upper eyelids is from the infratrochlear, supratrochlear, supraorbital and the lacrimal nerves from the ophthalmic branch (V1) of the trigeminal nerve (CN V). The skin of the lower eyelid is supplied by branches of the infratrochlear at the medial angle, the rest is supplied by branches of the infraorbital nerve of the maxillary branch (V2) of the trigeminal nerve.
## Blood supply
In humans, the eyelids are supplied by two arches on each upper and lower lid. The arches are formed by anastamoses of the lateral palpebral arteries and medial palpebral arteries, branching off from the lacrimal artery and ophthalmic artery, respectively.
## Muscles besides the Orbicularis oculi
Involuntary muscle fibers controlled by the sympathetic autonomic nervous system and open the eyelids away from each other, widening the eye aperture. The corrugator supercilii helps shield the eye from sun glare by pulling the eyebrow toward the bridge of the nose making a "roof" over the medial side of the eye and typical furrows in the forehead. The procerus muscle, on the bridge of the nose, fold the skin into tranmsverse furrows. The Frontalis
lifts the eyebrows (thus opposing the orbital portion of the orbicularis), especially when looking up. It also acts when a view is too distant or dim.
# Usage
When an eye becomes dry, "blinking" – closing the eyelid and opening it again rapidly – can help to spread moisture across the surface of the eye and ease the discomfort. Blinking also serves the purpose of helping to remove irritants which have landed in the eye. When a person chooses to blink one eye as a signal to another in a social setting, it is known as "winking."
Most animals with eyelids have a reflex to close the eyes when a threat comes too near. This is done involuntarily to protect the eye from contact with the threat. It is often strong enough to overcome any voluntary resistance.
Eyelids also serve the purpose of helping the animal to control the amount of light entering the eye (control of the iris is autonomic). Without eyelids, many animals would be helpless to block visual sensory overload under very bright light. Many animals also use eyelids to block light from reaching the eyes during sleeping cycles.
# Types
In humans, each eye has an upper and lower eyelid which operate as a pair, however, it is primarily the upper eyelid that moves across the exposed surface of the eye during blinking. Lower eyelids in most animals move vertically.
Many terrestrial vertebrates have an eyelid known as a nictitating membrane, or haw. This eyelid is closer to the eye than the outer lids and is usually transparent. The purpose of the nictitating membrane is to add protection to the eye from debris and irritation, and in land animals it also serves as a barrier while swimming. Camels, crocodiles, cats, birds, and polar bears are among animals that have this membrane. The nictitating membrane sweeps across the eye diagonally or horizontally. In humans, the plica semilunaris (or semilunar fold) is thought to be the vestigial remnant of the nictitating membrane.
It has been suggested that eyelids evolved as a way to remove debris from the eyes. Given that fish have a constant stream of water flowing over their eyes, it is not surprising that they do not have eyelids or need specialized membranes to perform this function.
## Double eyelid
A double eyelid is a type of eyelid where a crease exists. In contrast, a single eyelid has no crease. There is a wide variation in the location of the crease, particularly in the Asian double eyelid.
# Death
After death, it is common in many cultures to pull the eyelids of the deceased down to close the eyes. This a typical part of the last offices. | Eyelid
Template:Infobox Anatomy
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
# Overview
An eyelid is a thin fold of skin that covers and protects an eye. With the exception of the prepuce and the labia minora, it has the thinnest skin of the whole body. The levator palpebrae superioris muscle retracts the eyelid to "open" the eye. This can be either voluntarily or involuntarily. The human eyelid features a row of eyelashes which serve to heighten the protection of the eye from dust and foreign debris. "Palpebral" (and "blepharo") means relating to the eyelids.
# Anatomy
## Layers
In the human eyelid, there are various layers; from superficial to deep, they are:
skin, subcutaneous tissue, orbicularis oculi, orbital septum & tarsal plates, and palpebral conjunctiva. The meibomian glands lie within the eyelid and secrete the lipid part of the tearfilm.
### Skin
The skin is similar to areas elsewhere, but have more pigment cells. In diseased persons these may wander and cause a discoloration of the lids. It contains sweat glands and hairs, the latter becoming eyelashes as the border of the eyelid is met. [1]
## Innervation
In humans, the sensory nerve supply to the upper eyelids is from the infratrochlear, supratrochlear, supraorbital and the lacrimal nerves from the ophthalmic branch (V1) of the trigeminal nerve (CN V). The skin of the lower eyelid is supplied by branches of the infratrochlear at the medial angle, the rest is supplied by branches of the infraorbital nerve of the maxillary branch (V2) of the trigeminal nerve.
## Blood supply
In humans, the eyelids are supplied by two arches on each upper and lower lid. The arches are formed by anastamoses of the lateral palpebral arteries and medial palpebral arteries, branching off from the lacrimal artery and ophthalmic artery, respectively.
## Muscles besides the Orbicularis oculi
Involuntary muscle fibers controlled by the sympathetic autonomic nervous system and open the eyelids away from each other, widening the eye aperture. The corrugator supercilii helps shield the eye from sun glare by pulling the eyebrow toward the bridge of the nose making a "roof" over the medial side of the eye and typical furrows in the forehead. The procerus muscle, on the bridge of the nose, fold the skin into tranmsverse furrows. The Frontalis
lifts the eyebrows (thus opposing the orbital portion of the orbicularis), especially when looking up. It also acts when a view is too distant or dim.[2]
# Usage
When an eye becomes dry, "blinking" – closing the eyelid and opening it again rapidly – can help to spread moisture across the surface of the eye and ease the discomfort. Blinking also serves the purpose of helping to remove irritants which have landed in the eye. When a person chooses to blink one eye as a signal to another in a social setting, it is known as "winking."
Most animals with eyelids have a reflex to close the eyes when a threat comes too near. This is done involuntarily to protect the eye from contact with the threat. It is often strong enough to overcome any voluntary resistance.
Eyelids also serve the purpose of helping the animal to control the amount of light entering the eye (control of the iris is autonomic). Without eyelids, many animals would be helpless to block visual sensory overload under very bright light. Many animals also use eyelids to block light from reaching the eyes during sleeping cycles.
# Types
In humans, each eye has an upper and lower eyelid which operate as a pair, however, it is primarily the upper eyelid that moves across the exposed surface of the eye during blinking. Lower eyelids in most animals move vertically.
Many terrestrial vertebrates have an eyelid known as a nictitating membrane, or haw. This eyelid is closer to the eye than the outer lids and is usually transparent. The purpose of the nictitating membrane is to add protection to the eye from debris and irritation, and in land animals it also serves as a barrier while swimming. Camels, crocodiles, cats, birds, and polar bears are among animals that have this membrane. The nictitating membrane sweeps across the eye diagonally or horizontally. In humans, the plica semilunaris (or semilunar fold) is thought to be the vestigial remnant of the nictitating membrane.
It has been suggested that eyelids evolved as a way to remove debris from the eyes. Given that fish have a constant stream of water flowing over their eyes, it is not surprising that they do not have eyelids or need specialized membranes to perform this function.
## Double eyelid
A double eyelid is a type of eyelid where a crease exists. In contrast, a single eyelid has no crease. There is a wide variation in the location of the crease, particularly in the Asian double eyelid.
# Death
After death, it is common in many cultures to pull the eyelids of the deceased down to close the eyes. This a typical part of the last offices. | https://www.wikidoc.org/index.php/Eyelid | |
55f4d798829e9fec5cfeda6f784890178f3c06b4 | wikidoc | F-test | F-test
An F-test is any statistical test in which the test statistic has an F-distribution if the null hypothesis is true. The name was coined by George W. Snedecor, in honour of Sir Ronald A. Fisher. Fisher initially developed the statistic as the variance ratio in the 1920s. Examples include:
- The hypothesis that the means of multiple normally distributed populations, all having the same standard deviation, are equal. This is perhaps the most well-known of hypotheses tested by means of an F-test, and the simplest problem in the analysis of variance (ANOVA).
- The hypothesis that the standard deviations of two normally distributed populations are equal, and thus that they are of comparable origin.
Note that if it is equality of variances (or standard deviations) that is being tested, the F-test is extremely non-robust to non-normality. That is, even if the data displays only modest departures from the normal distribution, the test is unreliable and should not be used.
In many cases, the F-test statistic can be calculated through a straightforward process. Two regression models are required, one of which constrains one or more of the regression coefficients according to the null hypothesis. The test statistic is then based on a modified ratio of the sum of squares of residuals of the two models as follows:
Consider two models, 1 and 2, where model 1 is nested within model 2. That is, model 1 has p1 parameters, and model 2 has p2 parameters, where p2 > p1. (Any constant parameter in the model is included when counting the parameters. For instance, the simple linear model y = mx + b has p = 2 under this convention.) If there are n data points to estimate parameters of both models from, then calculate F as
where RSSi is the residual sum of squares of model i. If your regression model has been calculated with weights, then replace RSSi with χ2, the weighted sum of squared residuals. F here is distributed as an F-distribution, with (p2 − p1, n − p2) degrees of freedom; the probability that the decrease in χ2 associated with the addition of p2 − p1 parameters is solely due to chance is given by the probability associated with the F distribution at that point. The null hypothesis, that none of the additional p2 − p1 parameters is significantly correlated with the model, is rejected if the calculated F is greater than the F given by the critical value of F for some desired rejection probability (e.g. p = 0.05).
A table of F-test critical values can be found here and is usually included in most statistical texts.
# Footnotes
- ↑ Lomax, Richard G. (2007) "Statistical Concepts: A Second Course", p. 10, ISBN 0-8058-5850-4
- ↑ GraphPad Software Inc (2007/10/11). "How the F test works to compare models". GraphPad Software Inc. Check date values in: |date= (help).mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em} | F-test
An F-test is any statistical test in which the test statistic has an F-distribution if the null hypothesis is true. The name was coined by George W. Snedecor, in honour of Sir Ronald A. Fisher. Fisher initially developed the statistic as the variance ratio in the 1920s[1]. Examples include:
- The hypothesis that the means of multiple normally distributed populations, all having the same standard deviation, are equal. This is perhaps the most well-known of hypotheses tested by means of an F-test, and the simplest problem in the analysis of variance (ANOVA).
- The hypothesis that the standard deviations of two normally distributed populations are equal, and thus that they are of comparable origin.
Note that if it is equality of variances (or standard deviations) that is being tested, the F-test is extremely non-robust to non-normality. That is, even if the data displays only modest departures from the normal distribution, the test is unreliable and should not be used.
In many cases, the F-test statistic can be calculated through a straightforward process. Two regression models are required, one of which constrains one or more of the regression coefficients according to the null hypothesis. The test statistic is then based on a modified ratio of the sum of squares of residuals of the two models as follows:
Consider two models, 1 and 2, where model 1 is nested within model 2. That is, model 1 has p1 parameters, and model 2 has p2 parameters, where p2 > p1. (Any constant parameter in the model is included when counting the parameters. For instance, the simple linear model y = mx + b has p = 2 under this convention.) If there are n data points to estimate parameters of both models from, then calculate F as
where RSSi is the residual sum of squares of model i. If your regression model has been calculated with weights, then replace RSSi with χ2, the weighted sum of squared residuals. F here is distributed as an F-distribution, with (p2 − p1, n − p2) degrees of freedom; the probability that the decrease in χ2 associated with the addition of p2 − p1 parameters is solely due to chance is given by the probability associated with the F distribution at that point. The null hypothesis, that none of the additional p2 − p1 parameters is significantly correlated with the model, is rejected if the calculated F is greater than the F given by the critical value of F for some desired rejection probability (e.g. p = 0.05).
A table of F-test critical values can be found here and is usually included in most statistical texts.
# Footnotes
- ↑ Lomax, Richard G. (2007) "Statistical Concepts: A Second Course", p. 10, ISBN 0-8058-5850-4
- ↑ GraphPad Software Inc (2007/10/11). "How the F test works to compare models". GraphPad Software Inc. Check date values in: |date= (help).mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em} | https://www.wikidoc.org/index.php/F-test | |
08842e3aa403d84f803851fea0f67e9432f538b8 | wikidoc | Flavin | Flavin
# Overview
Flavin is a tricyclic heteronuclear organic ring based on pteridine whose biochemical source is the vitamin riboflavin. The flavin moiety is often attached with an adenosine diphosphate to form flavin adenine dinucleotide (FAD), and in other circumstances, is found as flavin mononucleotide (or FMN), a phosphorylated form of riboflavin. It is in one or the other of these forms that flavin is present as a prosthetic group in flavoproteins.
The flavin group is capable of undergoing oxidation-reduction reactions, and can accept either one electron in a two step process or can accept two electrons at once. In the form of FADH2, it is one of the cofactors that can transfer electrons to the electron transfer chain.
# FAD
Flavin adenine dinucleotide is a prosthetic group bound to many enzymes including ferredoxin-NADP+ reductase, monoamine oxidase, D-amino acid oxidase, glucose oxidase, xanthine oxidase, and acyl CoA dehydrogenase.
# FADH / FADH2
FADH and FADH2 are reduced forms of FAD. FADH2 is produced as a prosthetic group in succinate dehydrogenase, an enzyme involved in the citric acid cycle. In oxidative phosphorylation, two molecules of FADH2 typically yield 2.5 ATP.
# FMN
Flavin mononucleotide is a prosthetic group found in, amongst other proteins, NADH dehydrogenase, E.coli nitroreductase and old yellow enzyme. | Flavin
# Overview
Flavin is a tricyclic heteronuclear organic ring based on pteridine whose biochemical source is the vitamin riboflavin. The flavin moiety is often attached with an adenosine diphosphate to form flavin adenine dinucleotide (FAD), and in other circumstances, is found as flavin mononucleotide (or FMN), a phosphorylated form of riboflavin. It is in one or the other of these forms that flavin is present as a prosthetic group in flavoproteins.
The flavin group is capable of undergoing oxidation-reduction reactions, and can accept either one electron in a two step process or can accept two electrons at once. In the form of FADH2, it is one of the cofactors that can transfer electrons to the electron transfer chain.
# FAD
Flavin adenine dinucleotide is a prosthetic group bound to many enzymes including ferredoxin-NADP+ reductase, monoamine oxidase, D-amino acid oxidase, glucose oxidase, xanthine oxidase, and acyl CoA dehydrogenase.
# FADH / FADH2
FADH and FADH2 are reduced forms of FAD. FADH2 is produced as a prosthetic group in succinate dehydrogenase, an enzyme involved in the citric acid cycle. In oxidative phosphorylation, two molecules of FADH2 typically yield 2.5 ATP.
# FMN
Flavin mononucleotide is a prosthetic group found in, amongst other proteins, NADH dehydrogenase, E.coli nitroreductase and old yellow enzyme. | https://www.wikidoc.org/index.php/FADH | |
b10ba74a4157388d27168dfa422eca9a345cf4e0 | wikidoc | FAM20A | FAM20A
FAM20A is a protein that in humans is encoded by the FAM20A gene.
# Function
FAM20A belongs to an evolutionarily conserved family of secreted proteins expressed in many tissues. This locus encodes a protein that is likely secreted and may function in hematopoiesis.
A mutation at this locus has been associated with amelogenesis imperfecta and gingival hyperplasia syndrome. Alternatively spliced transcript variants have been identified.
# Clinical significance
A mutation in FAM20A was reported to be associated with amelogenesis imperfecta, an inherited enamel defect, and gingival hyperplasia syndrome.
Human mutations in FAM20A were also reported to cause Enamel-Renal Syndrome, an autosomal recessive disorder characterized by severe enamel hypoplasia, failed tooth eruption, intrapulpal calcifications, enlarged gingiva, and nephrocalcinosis. | FAM20A
FAM20A is a protein that in humans is encoded by the FAM20A gene.[1]
# Function
FAM20A belongs to an evolutionarily conserved family of secreted proteins expressed in many tissues. This locus encodes a protein that is likely secreted and may function in hematopoiesis.[2]
A mutation at this locus has been associated with amelogenesis imperfecta and gingival hyperplasia syndrome. Alternatively spliced transcript variants have been identified. [provided by RefSeq, Aug 2011]
# Clinical significance
A mutation in FAM20A was reported to be associated with amelogenesis imperfecta, an inherited enamel defect, and gingival hyperplasia syndrome.[3]
Human mutations in FAM20A were also reported to cause Enamel-Renal Syndrome, an autosomal recessive disorder characterized by severe enamel hypoplasia, failed tooth eruption, intrapulpal calcifications, enlarged gingiva, and nephrocalcinosis.[4] | https://www.wikidoc.org/index.php/FAM20A | |
3d490b30a34c81be90e2fe7da5fb8acba04dead6 | wikidoc | FAM40A | FAM40A
Protein FAM40A is a protein that is located on chromosome 1 in humans and is encoded by the FAM40A gene.
# Characteristics and secondary structure
FAM40A has an isoelectric point of 5.92 and a molecular weight of 95,575 daltons. It is predicted to have three transmembrane domains, making it a transmembrane protein. FAM40A does not contain a signal peptide and is also predicted to bind to DNA, possibly making it a membrane protein in the nuclear membrane.
The secondary structure of FAM40A is predicted to contain twenty-six alpha helices and two beta sheets. The 5' untranslated region of FAM40A is predicted to contain one stem-loop and the 3' untranslated region is predicted to contain eight stem-loop structures. Two miRNAs are predicted to bind to two of the stem-loop structures present in the 3' UTR region.
# Homology
FAM40A has no paralogs. However, it does have orthologs stretching all the way back to yeast. It has been suggested that FAM40A is a homolog to the yeast gene FAR11, which is involved in the recovery from cell cycle arrest.
The following table represents a small selection of orthologs found using searches in BLAST and BLAT. This is by no means a comprehensive list, however it does show the vast diversity of species where FAM40A orthologs are found.
# Expression
FAM40A is expressed in high levels during the blastocyst, eight-cell stage, and fetal stages of development. FAM40A has also been shown to be expressed in high levels in the mammary glands, brain, thymus, mouth and the testes. It has also been shown to be expressed in high levels in mammary gland tumors, leukemia cells, and germ cell tumors.
# Transcription Regulation
FAM40A is predicted to have a promoter region 789 base pairs upstream of the start of transcription. The SOX transcription factors are predicted to bind to the promoter region of the FAM40A gene, possibly indicating a role in sex determination.
# Interactions
FAM40A has been shown to interact with RP6-213H19.1, STRN, PDCD10, TRAF3IP3, STRN3, PPP2R1A, MOBKL3, CTTNBP2NL, STK24 and PPP2CA. | FAM40A
Protein FAM40A is a protein that is located on chromosome 1 in humans and is encoded by the FAM40A gene.[1][2][3]
# Characteristics and secondary structure
FAM40A has an isoelectric point of 5.92 and a molecular weight of 95,575 daltons.[4] It is predicted to have three transmembrane domains, making it a transmembrane protein.[5] FAM40A does not contain a signal peptide and is also predicted to bind to DNA, possibly making it a membrane protein in the nuclear membrane.[6][7]
The secondary structure of FAM40A is predicted to contain twenty-six alpha helices and two beta sheets.[8] The 5' untranslated region of FAM40A is predicted to contain one stem-loop and the 3' untranslated region is predicted to contain eight stem-loop structures.[9] Two miRNAs are predicted to bind to two of the stem-loop structures present in the 3' UTR region.[10]
# Homology
FAM40A has no paralogs. However, it does have orthologs stretching all the way back to yeast. It has been suggested that FAM40A is a homolog to the yeast gene FAR11, which is involved in the recovery from cell cycle arrest.[11][12]
The following table represents a small selection of orthologs found using searches in BLAST[13] and BLAT.[14] This is by no means a comprehensive list, however it does show the vast diversity of species where FAM40A orthologs are found.
# Expression
FAM40A is expressed in high levels during the blastocyst, eight-cell stage, and fetal stages of development.[15] FAM40A has also been shown to be expressed in high levels in the mammary glands, brain, thymus, mouth and the testes.[16] It has also been shown to be expressed in high levels in mammary gland tumors, leukemia cells, and germ cell tumors.[16]
# Transcription Regulation
FAM40A is predicted to have a promoter region 789 base pairs upstream of the start of transcription.[17] The SOX transcription factors are predicted to bind to the promoter region of the FAM40A gene, possibly indicating a role in sex determination.[17]
# Interactions
FAM40A has been shown to interact with RP6-213H19.1,[18] STRN,[18] PDCD10,[18] TRAF3IP3,[18] STRN3,[18] PPP2R1A,[18] MOBKL3,[18] CTTNBP2NL,[18] STK24[18][19] and PPP2CA.[18] | https://www.wikidoc.org/index.php/FAM40A | |
6e1be638da590535af61c6afbab796d1c3bb0099 | wikidoc | FAM43A | FAM43A
The family with sequence similarity 43 member A (FAM43A) gene, also known as; GCO3P195887, GC03P194406, GC03P191784, and NM_153690.3, codes for a 423 bp protein that is conserved in primates, and orthologs have been found in vertebrate and invertebrate species. Three transcripts have been identified, two protein coding isoforms (aAug10, bAug10), and a non-coding transcript (cAug10). Molecular weight of 45.8 kdal in the unphosphorylated state and isoelectric point of 6.1.
# Gene
Located on the long arm of Chromosome 3 at 3q29, FAM43A consists of 2,493 bases; and the translated protein contains a phosphotyrosine interaction domain, putative phosphoinositide binding site and putative peptide binding sites.
# Introduction
The FAM43A gene has been identified in cDNA screening as a possible cancer development and progression candidate gene. Unpublished data from Zhang et al. indicates that FAM43A could possess tumor suppressor function however the direct interaction is unknown. As well as playing a role in cancer development, FAM43A has been identified as a possible autism spectrum disorder (ASD) candidate gene, with mutations within the upstream single nucleotide polymorphism (SNP) rs789859 correlating with the presentation of ASD and learning disorder; suggesting that this SNP is the promoter region for the downstream FAM43A gene. The 2014 study completed by Baron-Cohen et al. involved the screening of 906 K SNPs within the genome to identify possible candidate genes, with FAM43A being the closest gene to the polymorphism.
# Protein
FAM43A and paralog FAM43B comprise a specific gene family, and share structural homology with the low-density lipoprotein receptor adaptor protein (LDLrP). Orthologs were identified in Mammalia, Aves, Actinopterygii, Reptilia, Hemichordata, Cephalochardata, Mollusca, Brachiopoda, Nematoda, and Arthropoda. No orthologs were identified beyond invertebrate species.
## Paralogs
FAM43A and paralog FAM43B comprise a specific gene family who share structural homology with the low-density lipoprotein receptor adaptor protein (LDLrP).
## Orthologs
A distant homolog was identified using NCBI protein BLAST, low density lipoprotein receptor adaptor protein 1-like in . However, when the sequence LOC111863195 was compared to Homo sapiens, it was discovered that the homolog mapped to chromosome 1, making it an ortholog of the paralog FAM43B. The fact that FAM43A protein cannot be traced back any further in evolutionary history than invertebrates indicates that this could be the point that FAM43A and paralog FAM43B diverged, approximately 797 million years ago (MYA).
# Expression
## Tissue specific expression
FAM43A protein is highly expressed in the mouth, vascular system, spleen and ear. Significant expression noted in the adipose tissue, umbilical cord, and bone, with highest expression in the infant developmental stage.
## Disease state expression
Expression is upregulated in head and neck tumor and bladder carcinoma, suggesting an oncogenic function. FAM43A expression is upregulated in Early T-cell precursor (ETP) acute lymphoblastic leukemia (ALL) (GDS4299) and triple negative breast cancer (TNBC) cell lines Hs578T (GDS4092). FAM43A expression map of Mus musculus brain indicated differential expression in the cortex, corpus callosum, and hypothalamus. The primary function of the corpus callosum is to innervate and connect the two hemispheres of the brain. The corpus callosum integrates motor, sensory, and cognitive performance between the cortical region in one hemisphere with its target in the other hemisphere. The hypothalamus links the nervous system to the endocrine system through the pituitary gland.
# Variation
3q29 microdeletion syndrome (monosomy 3q29) is caused by interstitial deletions of 3q29, mediated by nonallelic homologous recombination between low-copy repeats resulting in a common deletion. 3q29 microdeletion syndrome is marked by the loss of 1.6 million base pairs, including 5 known genes and 17 unknown transcripts. Genes phosphate and cytidyltransferase 1, choline alpha (PYT1A), P21 (RAC1) activated kinase 2 (PAK2), melanotransferrin (MFI2), discs large MAGUK scaffold protein 1 (DLG1), and 3-hydroxybutyrate dehydrogenase 1 (BDH1) have been confirmed and another 7 genes have been implicated with incomplete cDNAs, and the remaining hypothetical genes are yet to be confirmed experimentally. Presentation of 3q29 microdeletion syndrome has shown increased risk for schizophrenia. Gene neighbors PAK2 and DLG1 have been implicated due to interaction with neuroligin and the AMPA receptor subunit GluR1. In 2015, Guida et al identified a novel mutation proximal to the 3q29 microdeletion region that correlated with presentation of oculo auriculo vertebral spectrum (OAVS). Research of Robertson et al. revealed the presence of FAM43A mRNA in the fetal cochlea and association with development of normal hearing function. These findings indicate that variation in FAM43A could be responsible for the development of OAVS.
## Promoter
Transcription factor binding can be seen below within the FAM43A promoter region, searches were completed on the 500 bp preceding the start codon.
## 3' untranslated region
MicroRNA binding sites were identified and then compared to species conservation of FAM43A to determine likely 3' untranslated region (UTR) stem loop structures as depicted to the right.
## Post-translational Modification
FAM43 is predicted to be a nuclear protein, to identify function, structure and function for LDL receptor adaptor protein (LDLrP) was completed. Conserved residues Y52 and S93 are highlighted in the structure of LDLrP to the right. Three phosphorylation sites were identified with conservation between human and mouse genotypes at T112-p, S114-p, and T-379-p. The translated protein contains a primary and secondary nuclear localization signal and has a predicted GPI-linkage site at D407, and a Caspase 3 and 7 cleavage site from amino acids 404-408 indicating possible translocation from the cell membrane to the nucleus.
# Interacting Proteins
Direct interaction with SRPK2 (SRSF Protein Kinase 2), Serine/arginine-rich protein-specific kinase, which phosphorylates substrates at serine residues rich in Arginine/Serine dipeptides (RS domains), involved in the phosphorylation of SR splicing factors and the regulation of splicing. SRSF protein kinase 2 promotes neural apoptosis by up-regulating cyclin-D1 expression through the suppression of p53/TP53 phosphorylation. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases which regulate negative control of cell growth and division. FAM43A shows predicted interaction with the Abelson (ABL) kinase, and ABL members link diverse extracellular stimuli to signaling pathways controlling cell growth, survival, invasion, adhesion, and migration. | FAM43A
The family with sequence similarity 43 member A (FAM43A) gene, also known as; GCO3P195887, GC03P194406, GC03P191784,[1] and NM_153690.3,[2] codes for a 423 bp protein that is conserved in primates, and orthologs have been found in vertebrate and invertebrate species.[3] Three transcripts have been identified, two protein coding isoforms (aAug10, bAug10), and a non-coding transcript (cAug10).[4] Molecular weight of 45.8 kdal in the unphosphorylated state and isoelectric point of 6.1.[5]
# Gene
Located on the long arm of Chromosome 3 at 3q29, FAM43A consists of 2,493 bases; and the translated protein contains a phosphotyrosine interaction domain, putative phosphoinositide binding site and putative peptide binding sites.[6]
# Introduction
The FAM43A gene has been identified in cDNA screening as a possible cancer development and progression candidate gene.[7] Unpublished data from Zhang et al. indicates that FAM43A could possess tumor suppressor function[8] however the direct interaction is unknown. As well as playing a role in cancer development, FAM43A has been identified as a possible autism spectrum disorder (ASD) candidate gene, with mutations within the upstream single nucleotide polymorphism (SNP) rs789859 correlating with the presentation of ASD and learning disorder; suggesting that this SNP is the promoter region for the downstream FAM43A gene.[9] The 2014 study completed by Baron-Cohen et al. involved the screening of 906 K SNPs within the genome to identify possible candidate genes, with FAM43A being the closest gene to the polymorphism.
# Protein
FAM43A and paralog FAM43B comprise a specific gene family, and share structural homology with the low-density lipoprotein receptor adaptor protein (LDLrP).[10][11] Orthologs were identified in Mammalia, Aves, Actinopterygii, Reptilia, Hemichordata, Cephalochardata, Mollusca, Brachiopoda, Nematoda, and Arthropoda. No orthologs were identified beyond invertebrate species.[12]
## Paralogs
FAM43A and paralog FAM43B comprise a specific gene family who share structural homology with the low-density lipoprotein receptor adaptor protein (LDLrP).[13]
## Orthologs
A distant homolog was identified using NCBI protein BLAST, low density lipoprotein receptor adaptor protein 1-like in [Cryptotermes secundus]. However, when the sequence LOC111863195 was compared to Homo sapiens, it was discovered that the homolog mapped to chromosome 1, making it an ortholog of the paralog FAM43B. The fact that FAM43A protein cannot be traced back any further in evolutionary history than invertebrates indicates that this could be the point that FAM43A and paralog FAM43B diverged, approximately 797 million years ago (MYA).
# Expression
## Tissue specific expression
FAM43A protein is highly expressed in the mouth, vascular system, spleen and ear. Significant expression noted in the adipose tissue, umbilical cord, and bone, with highest expression in the infant developmental stage.[14]
## Disease state expression
Expression is upregulated in head and neck tumor and bladder carcinoma, suggesting an oncogenic function.[15] FAM43A expression is upregulated in Early T-cell precursor (ETP) acute lymphoblastic leukemia (ALL) (GDS4299) and triple negative breast cancer (TNBC) cell lines Hs578T (GDS4092).[16] FAM43A expression map of Mus musculus brain indicated differential expression in the cortex, corpus callosum, and hypothalamus.[17] The primary function of the corpus callosum is to innervate and connect the two hemispheres of the brain. The corpus callosum integrates motor, sensory, and cognitive performance between the cortical region in one hemisphere with its target in the other hemisphere.[18] The hypothalamus links the nervous system to the endocrine system through the pituitary gland.
# Variation
3q29 microdeletion syndrome (monosomy 3q29) is caused by interstitial deletions of 3q29, mediated by nonallelic homologous recombination between low-copy repeats resulting in a common deletion.[19] 3q29 microdeletion syndrome is marked by the loss of 1.6 million base pairs, including 5 known genes and 17 unknown transcripts. Genes phosphate and cytidyltransferase 1, choline alpha (PYT1A), P21 (RAC1) activated kinase 2 (PAK2), melanotransferrin (MFI2), discs large MAGUK scaffold protein 1 (DLG1), and 3-hydroxybutyrate dehydrogenase 1 (BDH1) have been confirmed and another 7 genes have been implicated with incomplete cDNAs, and the remaining hypothetical genes are yet to be confirmed experimentally.[20] Presentation of 3q29 microdeletion syndrome has shown increased risk for schizophrenia. Gene neighbors PAK2 and DLG1 have been implicated due to interaction with neuroligin and the AMPA receptor subunit GluR1.[21] In 2015, Guida et al identified a novel mutation proximal to the 3q29 microdeletion region that correlated with presentation of oculo auriculo vertebral spectrum (OAVS).[22] Research of Robertson et al. revealed the presence of FAM43A mRNA in the fetal cochlea and association with development of normal hearing function.[23] These findings indicate that variation in FAM43A could be responsible for the development of OAVS.
## Promoter
Transcription factor binding can be seen below within the FAM43A promoter region,[24] searches were completed on the 500 bp preceding the start codon.
## 3' untranslated region
MicroRNA binding sites were identified[25] and then compared to species conservation of FAM43A to determine likely 3' untranslated region (UTR) stem loop structures as depicted to the right.
## Post-translational Modification
FAM43 is predicted to be a nuclear protein, to identify function, structure and function for LDL receptor adaptor protein (LDLrP) was completed.[26] Conserved residues Y52 and S93 are highlighted in the structure of LDLrP to the right. Three phosphorylation sites were identified with conservation between human and mouse genotypes[27] at T112-p, S114-p, and T-379-p. The translated protein contains a primary and secondary nuclear localization signal and has a predicted GPI-linkage site at D407,[28] and a Caspase 3 and 7 cleavage site from amino acids 404-408[29] indicating possible translocation from the cell membrane to the nucleus.
# Interacting Proteins
Direct interaction with SRPK2 (SRSF Protein Kinase 2), Serine/arginine-rich protein-specific kinase, which phosphorylates substrates at serine residues rich in Arginine/Serine dipeptides (RS domains), involved in the phosphorylation of SR splicing factors and the regulation of splicing. SRSF protein kinase 2 promotes neural apoptosis by up-regulating cyclin-D1 expression through the suppression of p53/TP53 phosphorylation.[30] Protein phosphatase 2A is one of the four major Ser/Thr phosphatases which regulate negative control of cell growth and division.[31] FAM43A shows predicted interaction with the Abelson (ABL) kinase, and ABL members link diverse extracellular stimuli to signaling pathways controlling cell growth, survival, invasion, adhesion, and migration.[32] | https://www.wikidoc.org/index.php/FAM43A | |
db95b73ba09a41cc42389792631cf50bdc5c764d | wikidoc | FAM46A | FAM46A
Protein FAM46A is a protein that in humans is encoded by the FAM46A gene. Aliases for Fam46A include HBV X-Transactivated Gene 11 Protein, C6orf37, and XTP11. The gene contains 6 introns, and is 6982 base pairs long. The transcribed mRNA is 2231 base pairs long and contains 2 exons, 589 and 1128 base pairs, with 4 alternative splice isoforms.
# Expression
Expression of Fam46A is found to be exceptionally high in Placental tissue, Pineal Gland, and Pituitary Gland with low to moderate expression within Bone Marrow, Uterus, and Salivary glands.
# Protein
The human FAM46A protein is 461 Amino Acids long.
# Function
The function of Fam46A is currently unknown but there is a Variable Number Tandem Repeat in the first exon of Fam46A that has been explored within various populations and have been attempted to be linked to various retinal diseases as well as colon cancer. | FAM46A
Protein FAM46A is a protein that in humans is encoded by the FAM46A gene. Aliases for Fam46A include HBV X-Transactivated Gene 11 Protein, C6orf37, and XTP11.[1] The gene contains 6 introns, and is 6982 base pairs long.[2] The transcribed mRNA is 2231 base pairs long and contains 2 exons, 589 and 1128 base pairs, with 4 alternative splice isoforms.[3]
# Expression
Expression of Fam46A is found to be exceptionally high in Placental tissue, Pineal Gland, and Pituitary Gland with low to moderate expression within Bone Marrow, Uterus, and Salivary glands.[4]
# Protein
The human FAM46A protein is 461 Amino Acids long.[5]
# Function
The function of Fam46A is currently unknown but there is a Variable Number Tandem Repeat in the first exon of Fam46A that has been explored within various populations and have been attempted to be linked to various retinal diseases as well as colon cancer.[6][7] | https://www.wikidoc.org/index.php/FAM46A | |
060b67aae78fd93cc173b8bcc24f5c8160bd4c23 | wikidoc | FAM46C | FAM46C
Protein FAM46C also known as family with sequence similarity 46, member C is a protein that, in humans, is encoded by the FAM46C gene at locus 1p12 spanning base pairs from 118,148,556 to 118,171,011.
# Summary
FAM46C is a protein of unknown function consisting of 391 amino acid residues that are translated from an mRNA consisting of 5720 base pairs. FAM46C was initially sequenced as part of the Full-length long Japan genomic sequencing project. FAM46C is found on chromosome 1 at the locus 1p12 FAM46C contains one domain of unknown function, DUF1693, and as such has been placed in the DUF1693 protein family. This protein family has been established as a part of the Nucleotidyltransferase superfamily and contains 4 nematode prion-like proteins. FAM46C was placed into group XXV of the nucleotidyltransferase superfamily along with 3 other Homo sapiens FAM46 proteins (A, B, D).
It has been suggested that FAM46C may be functionally involved with the Type 1 interferon response. Deletion and/ or mutation of FAM46C has been associated with impaired overall survival in Myeloma patients.
# Gene
Homo sapiens FAM46C spans 22,456 bases on chromosome 1. Microarray data suggests that human FAM46C displays elevated expression levels in bone marrow, CD71+ early erythroid, various B-cells, T-cells, and lymphocytes, as well as all tissues associated with testes.
# Evolution and homology
Homo sapiens FAM46C is highly conserved in close orthologs with only small changes in protein AA sequence when comparing to other mammals.
FAM46C and specifically the DUF1693 is traceable throughout the known metazoans, with a distant homolog found in Trichoplax adhaerens, a member of the basal multicellular organismal group Placozoa.
## Paralogs
Homo sapiens FAM46C is paralogous to 3 separate known FAM46 proteins, all of which contain DUF1693.
## Orthologs
There are numerous FAM46C orthologs present throughout the current catalog of multicellular organisms, all of which exhibit impressive conservation of domain of unknown function 1693. The most notable ortholog is taken to be TRIADDRAFT14293, a gene of the species Trichoplax adhaerens. This ortholog provides evidence that FAM46C is a member of a group of proteins containing highly conserved amino acid residues, and as such it is thought to provide some highly important function, as would be expected when considering its possible nucleotidyltransferase activity.
## Homologous domains
In order to determine possible conserved structures, a predictive approach was utilized with regards to comparison of FAM46C with the most distant homolog available, that of Trichoplax adhearens. PHYRE2 was used to predict protein secondary structure of human FAM46C as well as trichoplax TRIADDRAFT-14293. We are able to visualize possible structures predicted with high confidence in both the human gene, as well as the placozoan gene. This preliminary prediction offers some insight into important structures, most probably of catalytic and/or binding function.
## Phylogeny
Based on multiple sequence alignments generated by ClustalW an unrooted phylogenetic tree was generated for select FAM46C orthologs in order to demonstrate the diverse occurrences of FAM46C-like genes throughout the current evolutionary catalog. For posterity, many orthologs were omitted (see ortholog table above; many were omitted from this table as well).
# Protein structure
"Homo sapiens" FAM46C encodes a 391 amino acid protein with no known isoforms. "Homo sapiens" FAM46C has not been crystallized and its secondary structure has not yet been determined as of May 2013. FAM46C has a predicted isoelectric point of 5.338. The protein contains one domain of unknown function, DUF1693 (Pfam: PF07984)
A Leucine zipper pattern was found beginning at Lys113 and ending at Lys134. This could help distinguish nuclear proteins from non-nuclear proteins, however all other subsets of analyses using PSORTII have predicted that FAM46C is strictly a cytosolic protein.
No other significant protein structural motifs have been predicted.
## Protein-protein interactions
FAM46C has been experimentally shown to interact physically with at least 4 separate proteins, with other interactions that have been predicted | FAM46C
Protein FAM46C also known as family with sequence similarity 46, member C is a protein that, in humans, is encoded by the FAM46C gene at locus 1p12 spanning base pairs from 118,148,556 to 118,171,011.
# Summary
FAM46C is a protein of unknown function consisting of 391 amino acid residues that are translated from an mRNA consisting of 5720 base pairs. FAM46C was initially sequenced as part of the Full-length long Japan genomic sequencing project. FAM46C is found on chromosome 1 at the locus 1p12 FAM46C contains one domain of unknown function, DUF1693, and as such has been placed in the DUF1693 protein family. This protein family has been established as a part of the Nucleotidyltransferase superfamily[1] and contains 4 nematode prion-like proteins. FAM46C was placed into group XXV of the nucleotidyltransferase superfamily[1] along with 3 other Homo sapiens FAM46 proteins (A, B, D).
It has been suggested that FAM46C may be functionally involved with the Type 1 interferon response.[2] Deletion and/ or mutation of FAM46C has been associated with impaired overall survival in Myeloma patients.[3]
# Gene
Homo sapiens FAM46C spans 22,456 bases on chromosome 1. Microarray data suggests that human FAM46C displays elevated expression levels in bone marrow, CD71+ early erythroid, various B-cells, T-cells, and lymphocytes, as well as all tissues associated with testes.[4]
# Evolution and homology
Homo sapiens FAM46C is highly conserved in close orthologs with only small changes in protein AA sequence when comparing to other mammals.
FAM46C and specifically the DUF1693 is traceable throughout the known metazoans, with a distant homolog found in Trichoplax adhaerens, a member of the basal multicellular organismal group Placozoa.
## Paralogs
Homo sapiens FAM46C is paralogous to 3 separate known FAM46 proteins, all of which contain DUF1693.
## Orthologs
There are numerous FAM46C orthologs present throughout the current catalog of multicellular organisms, all of which exhibit impressive conservation of domain of unknown function 1693. The most notable ortholog is taken to be TRIADDRAFT14293, a gene of the species Trichoplax adhaerens. This ortholog provides evidence that FAM46C is a member of a group of proteins containing highly conserved amino acid residues, and as such it is thought to provide some highly important function, as would be expected when considering its possible nucleotidyltransferase activity.
## Homologous domains
In order to determine possible conserved structures, a predictive approach was utilized with regards to comparison of FAM46C with the most distant homolog available, that of Trichoplax adhearens. PHYRE2[5] was used to predict protein secondary structure of human FAM46C as well as trichoplax TRIADDRAFT-14293. We are able to visualize possible structures predicted with high confidence in both the human gene, as well as the placozoan gene. This preliminary prediction offers some insight into important structures, most probably of catalytic and/or binding function.
## Phylogeny
Based on multiple sequence alignments generated by ClustalW an unrooted phylogenetic tree was generated for select FAM46C orthologs in order to demonstrate the diverse occurrences of FAM46C-like genes throughout the current evolutionary catalog. For posterity, many orthologs were omitted (see ortholog table above; many were omitted from this table as well).
# Protein structure
"Homo sapiens" FAM46C encodes a 391 amino acid protein with no known isoforms. "Homo sapiens" FAM46C has not been crystallized and its secondary structure has not yet been determined as of May 2013. FAM46C has a predicted isoelectric point of 5.338. The protein contains one domain of unknown function, DUF1693 (Pfam: PF07984)
A Leucine zipper pattern was found beginning at Lys113 and ending at Lys134. This could help distinguish nuclear proteins from non-nuclear proteins, however all other subsets of analyses using PSORTII[6] have predicted that FAM46C is strictly a cytosolic protein.
No other significant protein structural motifs have been predicted.
## Protein-protein interactions
FAM46C has been experimentally shown to interact physically with at least 4 separate proteins, with other interactions that have been predicted[7] | https://www.wikidoc.org/index.php/FAM46C | |
aabd3c3fa3467bb7da42a179363d90d9d3eb5113 | wikidoc | FAM49A | FAM49A
Family with sequence similarity 49, member A, also known as FAM49A, is a protein which in humans is encoded by the FAM49A gene.
# Gene
Fam49A is located on human chromosome 2, at 2p24.3. It has 1512 base pairs in the reference sequence mRNA transcript.
# Protein
The Fam49A gene product is a 323 amino acid protein. The protein contains two domains: Residues 15-319 comprise the "Domain of Unknown Function 1394" (DUF1394, Pfam PF07159). Residues 67->281 comprise the "Cytoplasmic Fragile X Interacting Superfamily" region. | FAM49A
Family with sequence similarity 49, member A, also known as FAM49A, is a protein which in humans is encoded by the FAM49A gene.[1]
# Gene
Fam49A is located on human chromosome 2, at 2p24.3. It has 1512 base pairs in the reference sequence mRNA transcript.[2]
# Protein
The Fam49A gene product is a 323 amino acid protein. The protein contains two domains: Residues 15-319 comprise the "Domain of Unknown Function 1394" (DUF1394, Pfam PF07159). Residues 67->281 comprise the "Cytoplasmic Fragile X Interacting Superfamily" region.[3] | https://www.wikidoc.org/index.php/FAM49A | |
9cc4a2199153731ce4343e6ba6e16c9785b5150e | wikidoc | FAM63A | FAM63A
Family with sequence similarity 63, member A is a protein that, in humans, is encoded by the FAM63A gene. It is located on the minus strand of chromosome 1 at locus 1q21.3.
Evolutionarily, FAM63A orthologs are found in most vertebrates, and distant homologs of FAM63A are found in invertebrates. FAM63A is ubiquitously expressed throughout human tissues, and it is present during every stage of development.
It has been linked to a biomarker in Chronic Kidney Disease and Alzheimer's Disease.
# Gene
## Locus
FAM63A is located on the minus strand of chromosome 1 at band 1q21.3, spanning 11,829 bp. Other genes surrounding FAM63A include ANXA9 and Prune.
## Aliases
FAM63A has two aliases KIAA1390 and PR11-316M1.5.
# mRNA
## Primary structure
In humans, there are four isoforms of FAM63A, and there are 10 predicted isoforms. Isoform 1 of FAM63A has a molecular weight of 51.8 kilodaltons, and it contains 11 exons. The different isoforms tend to differ at the 5' or 3' end by truncation. Transcription produces 23 introns, 14 spliced variants, and 6 unspliced forms.
# Protein
## Domains and motifs
FAM63A contains a domain of unknown function (DUF 544). DUF544 contains 125 amino acids, running from Met143 to Thr267. Although not completely conserved, this domain is highly conserved across vertebrates, invertebrates, and plants. FAM63A does not contain a transmembrane domain, and it is found primarily in nuclear regions of the cell.
Two repeats of four glutamines are seen from amino acid 400-403 and from amino acid 426-429, leading to an elevated glutamine composition at the C-terminus.
## Composition
FAM63A is composed of 469 amino acids. There is an increased presence of glutamine found near the C terminus making FAM63A glutamine rich.
FAM63A contains a greater amount of negatively charged (acidic) amino acids than positively charged (basic) amino acids which makes FAM63A a slightly acidic protein. Acidic amino acids such as aspartic acid and glutamic acid are more prevalent than the basic amino acids such as lysine and arginine. This overall acidic composition gives FAM63A an acidic isoelectric point of 4.6.
## Post-translational modifications
FAM63A contains 25 phosphorylation sites in humans, including 12 serine, 10 threonine, and 3 tyrosine. Additionally, there are 5 N-myristoylation sites, and there is 1 prenylation site. FAM63A contains no glycosylation sites, transmembrane domains, or signal peptides.
## Secondary structure
The secondary structure for FAM63A has not been explicitly determined. There are, however, predictions for a possible secondary structure. There is a coiled-coil domain at the end of the protein, and in the predicted secondary structure, there is an alpha helix between amino acids 410 and 436. This helix is conserved throughout more distant orthologs of FAM63A. These data support each other, and it gives a confident prediction of the secondary structure.
## Interacting proteins
The following genes have interactions with FAM63A: GSPT2, NAA38, RNMT, CSNIK1G2, ACOX1, PSMC1, SLC25A37, MMS19, DIAPH1, ME1, GAPDH, UBC.
After performing a yeast two-hybrid screen, it was found that NAA38 and FAM63A interact.
# Homology/evolution
In FAM63A, there are several amino acids that are conserved in all vertebrates for which sequences are available. Gly239 is the only amino acid that is conserved in all vertebrates, invertebrates, and plants for which sequences are available. Because there is only one amino acid that is absolutely conserved, a possible function for the conserved Glycine was not deduced. The 25 amino acid sequence ranging from Val313 to Gly338 is the most highly conserved in all vertebrates, invertebrates, and plants for which sequences are available. Although the sequence is not absolutely conserved, it is very highly conserved, even in the most distantly related organisms like fungi and plants.
## Orthologs
The protein FAM63A has several strict orthologs. These strict orthologs are found in organisms ranging from Primates to Fish.
FAM63A evolved through time at a relatively moderate rate.
## Paralogs
The protein FAM63A has only one known paralog: FAM63B. FAM63B is predicted as having a molecular function in the cell. All of the vertebrates for which sequences are available have two copies of the FAM63 gene, both A and B. FAM63A and FAM63B likely split apart around 666 million years ago, as the closest relative to Homo sapiens containing only one FAM63 is a tapeworm, which diverged 666 million years ago.
# Expression
## Promoter
The promoter region contains a number of transcription factors. Those with high scores include estrogen response elements, TATA boxes, glucocoticoid response elements, and Ccaat/enchancer binding proteins. Experimental data reveals that FAM63A expression decreases when the estrogen receptor is not present, suggesting that the estrogen response elements may serve as an important promoter regulatory mechanism for this protein.
## Protein expression
FAM63A is a protein that is ubiquitously expressed across human tissues and throughout development. Although FAM63A is expressed ubiquitously, there are certain tissues that have higher levels of expression including the heart, thyroid, ganglia, and blood.
# Clinical significance
Although there is no specific function determined for FAM63A, there are a few researchers who have discovered possible functions. It has been postulated that FAM63A may be associated with renal function and Chronic Kidney Disease.
Figgins, Minster, and Demirci examined 17,343 functional single nucleotide polymorphisms, demonstrating a strong association between Alzheimer's Disease duration and FAM63A. Another gene located on 1q21, CTSS, was also strongly associated with disease duration, the authors believe that there is a strong linkage disequilibrium between the two genes. FAM63A was identified as one of 39 genes exclusively expressed in CML cells, grouped with four other genes believed to function in protein ligation. | FAM63A
Family with sequence similarity 63, member A is a protein that, in humans, is encoded by the FAM63A gene. It is located on the minus strand of chromosome 1 at locus 1q21.3.[1]
Evolutionarily, FAM63A orthologs are found in most vertebrates, and distant homologs of FAM63A are found in invertebrates.[2] FAM63A is ubiquitously expressed throughout human tissues, and it is present during every stage of development.[3]
It has been linked to a biomarker in Chronic Kidney Disease and Alzheimer's Disease.[4]
# Gene
## Locus
FAM63A is located on the minus strand of chromosome 1 at band 1q21.3, spanning 11,829 bp. Other genes surrounding FAM63A include ANXA9 and Prune.[5]
## Aliases
FAM63A has two aliases KIAA1390 and PR11-316M1.5.[6]
# mRNA
## Primary structure
In humans, there are four isoforms of FAM63A, and there are 10 predicted isoforms. Isoform 1 of FAM63A has a molecular weight of 51.8 kilodaltons, and it contains 11 exons.[7][8] The different isoforms tend to differ at the 5' or 3' end by truncation. Transcription produces 23 introns, 14 spliced variants, and 6 unspliced forms.[9]
# Protein
## Domains and motifs
FAM63A contains a domain of unknown function (DUF 544). DUF544 contains 125 amino acids, running from Met143 to Thr267.[10] Although not completely conserved, this domain is highly conserved across vertebrates, invertebrates, and plants.[11] FAM63A does not contain a transmembrane domain, and it is found primarily in nuclear regions of the cell.
[12]
Two repeats of four glutamines are seen from amino acid 400-403 and from amino acid 426-429, leading to an elevated glutamine composition at the C-terminus.
## Composition
FAM63A is composed of 469 amino acids.[13] There is an increased presence of glutamine found near the C terminus making FAM63A glutamine rich.
FAM63A contains a greater amount of negatively charged (acidic) amino acids than positively charged (basic) amino acids which makes FAM63A a slightly acidic protein. Acidic amino acids such as aspartic acid and glutamic acid are more prevalent than the basic amino acids such as lysine and arginine. This overall acidic composition gives FAM63A an acidic isoelectric point of 4.6.[14]
## Post-translational modifications
FAM63A contains 25 phosphorylation sites in humans, including 12 serine, 10 threonine, and 3 tyrosine. Additionally, there are 5 N-myristoylation sites, and there is 1 prenylation site. FAM63A contains no glycosylation sites, transmembrane domains, or signal peptides.
[15]
## Secondary structure
The secondary structure for FAM63A has not been explicitly determined. There are, however, predictions for a possible secondary structure. There is a coiled-coil domain at the end of the protein, and in the predicted secondary structure, there is an alpha helix between amino acids 410 and 436. This helix is conserved throughout more distant orthologs of FAM63A. These data support each other, and it gives a confident prediction of the secondary structure.[16]
## Interacting proteins
The following genes have interactions with FAM63A: GSPT2, NAA38, RNMT, CSNIK1G2, ACOX1, PSMC1, SLC25A37, MMS19, DIAPH1, ME1, GAPDH, UBC.
[17]
After performing a yeast two-hybrid screen, it was found that NAA38 and FAM63A interact.[18]
# Homology/evolution
In FAM63A, there are several amino acids that are conserved in all vertebrates for which sequences are available. Gly239 is the only amino acid that is conserved in all vertebrates, invertebrates, and plants for which sequences are available. Because there is only one amino acid that is absolutely conserved, a possible function for the conserved Glycine was not deduced. The 25 amino acid sequence ranging from Val313 to Gly338 is the most highly conserved in all vertebrates, invertebrates, and plants for which sequences are available. Although the sequence is not absolutely conserved, it is very highly conserved, even in the most distantly related organisms like fungi and plants.
## Orthologs
The protein FAM63A has several strict orthologs. These strict orthologs are found in organisms ranging from Primates to Fish.[19]
FAM63A evolved through time at a relatively moderate rate.
## Paralogs
The protein FAM63A has only one known paralog: FAM63B. FAM63B is predicted as having a molecular function in the cell.[20] All of the vertebrates for which sequences are available have two copies of the FAM63 gene, both A and B. FAM63A and FAM63B likely split apart around 666 million years ago, as the closest relative to Homo sapiens containing only one FAM63 is a tapeworm, which diverged 666 million years ago.[21]
# Expression
## Promoter
The promoter region contains a number of transcription factors.[22] Those with high scores include estrogen response elements, TATA boxes, glucocoticoid response elements, and Ccaat/enchancer binding proteins. Experimental data reveals that FAM63A expression decreases when the estrogen receptor is not present, suggesting that the estrogen response elements may serve as an important promoter regulatory mechanism for this protein.[23]
## Protein expression
FAM63A is a protein that is ubiquitously expressed across human tissues and throughout development. Although FAM63A is expressed ubiquitously, there are certain tissues that have higher levels of expression including the heart, thyroid, ganglia, and blood.[24]
# Clinical significance
Although there is no specific function determined for FAM63A, there are a few researchers who have discovered possible functions. It has been postulated that FAM63A may be associated with renal function and Chronic Kidney Disease.[4]
Figgins, Minster, and Demirci examined 17,343 functional single nucleotide polymorphisms, demonstrating a strong association between Alzheimer's Disease duration and FAM63A.[25] Another gene located on 1q21, CTSS, was also strongly associated with disease duration, the authors believe that there is a strong linkage disequilibrium between the two genes. FAM63A was identified as one of 39 genes exclusively expressed in CML cells, grouped with four other genes believed to function in protein ligation. | https://www.wikidoc.org/index.php/FAM63A | |
3be07dd191887abba90fe75f32b31585ba3e8f83 | wikidoc | FAM71D | FAM71D
FAM71D, also known as chromosome 14 open reading frame 54 (C14orf54), is a protein that in humans is encoded by the FAM71D gene on Chromosome 14. Orthologs of FAM71D reach as far back in evolution to Reptiles, however, it is closer in homology to primates than any other orthologs. FAM71D has 6 paralogs: FAM71A, FAM71B, FAM71C, FAM71E1, FAM71F1, and FAM71F2 which encode a protein of unknown function.
# Gene
In humans, FAM71D is located at 14q23.3 and stretches between positions 67189393 and 67228550 (span 39157 bp). It codes for at least 10 unique human protein isoforms: the primary isoform (422 aa; also denoted X1), isoform X2 (417 aa), isoform X3 (413 aa), isoform X4 (400 aa), isoform X5 (399 aa), isoform X6 (398 aa), isoform X7 (392 aa), isoform X8 (389 aa), isoform X9 (347 aa), isoform X10 (336 aa) In humans, FAM71D codes for an mRNA strand that is 1790 base pairs long. The human mRNA is composed of a 5' untranslated region that is 290 bases long and a 3' untranslated region that is 231 bases long The gene has the following neighbours on the same chromosome:
File:Gene Neighbors.png
# Homology
# Protein
The primary protein encoded by FAM71D in humans is 422 amino acids long with a molecular weight of 47076 Da. The protein is part of a functionally uncharacterized family of proteins (pfam 12480) with a domain of unknown function DUF3699.
## Structure
Several tools are available to predict the secondary structure of a protein. One tool that combines the results of few of them is PELE on SDSC Biology WorkBench. According to this tool, the protein's secondary structure is mostly alpha helices, beta stands and coiled-coiled domains.
## Post Translational Modifications
Like any other protein, this protein undergoes post-translational modifications. FAM71D is predicted to contain 2 nuclear export signals, and lacks both a signal peptide and transmembrane domains.
## Interactions
FAM71D interacts with PGK2, TUBA3C, and HSPB1. FAM71D is also predicted to interact with the following proteins using STRING:
# Expression
FAM71D is primarily expressed in the testis of humans only expressed during the adult developmental stage. GEO microarray data also supports the expression of FAM71D in humans
File:Expression FAM71D.png
# Clinical Relevance
No studies have directly associated FAM71D protein with certain diseases. However, using NCBI GEO Profiles, FAM71D was found to be over-expressed in patients suffering from unruptured intracranial aneurysms. | FAM71D
FAM71D, also known as chromosome 14 open reading frame 54 (C14orf54), is a protein that in humans is encoded by the FAM71D gene on Chromosome 14.[1] Orthologs of FAM71D reach as far back in evolution to Reptiles, however, it is closer in homology to primates than any other orthologs. FAM71D has 6 paralogs: FAM71A, FAM71B, FAM71C, FAM71E1, FAM71F1, and FAM71F2[2] which encode a protein of unknown function.
# Gene
In humans, FAM71D is located at 14q23.3 and stretches between positions 67189393 and 67228550 (span 39157 bp).[3] It codes for at least 10 unique human protein isoforms: the primary isoform (422 aa; also denoted X1),[4][5][6][7] isoform X2 (417 aa),[8] isoform X3 (413 aa),[9] isoform X4 (400 aa),[10] isoform X5 (399 aa),[11] isoform X6 (398 aa),[12] isoform X7 (392 aa),[13][14] isoform X8 (389 aa),[15] isoform X9 (347 aa),[16] isoform X10 (336 aa)[17] In humans, FAM71D codes for an mRNA strand that is 1790 base pairs long. The human mRNA is composed of a 5' untranslated region that is 290 bases long and a 3' untranslated region that is 231 bases long[18] The gene has the following neighbours on the same chromosome:
File:Gene Neighbors.png[19]
# Homology
[20]
# Protein
The primary protein encoded by FAM71D in humans is 422 amino acids long with a molecular weight of 47076 Da.[21] The protein is part of a functionally uncharacterized family of proteins (pfam 12480) with a domain of unknown function DUF3699.[22]
## Structure
Several tools are available to predict the secondary structure of a protein. One tool that combines the results of few of them is PELE on SDSC Biology WorkBench.[23] According to this tool, the protein's secondary structure is mostly alpha helices, beta stands and coiled-coiled domains.
## Post Translational Modifications
Like any other protein, this protein undergoes post-translational modifications. FAM71D is predicted to contain 2 nuclear export signals,[24] and lacks both a signal peptide[25] and transmembrane domains.[26]
## Interactions
FAM71D interacts with PGK2,[27] TUBA3C,[27] and HSPB1.[28] FAM71D is also predicted to interact with the following proteins using STRING:[29]
# Expression
FAM71D is primarily expressed in the testis of humans only expressed during the adult developmental stage.[30] GEO microarray data also supports the expression of FAM71D in humans[31]
File:Expression FAM71D.png[32]
# Clinical Relevance
No studies have directly associated FAM71D protein with certain diseases. However, using NCBI GEO Profiles, FAM71D was found to be over-expressed in patients suffering from unruptured intracranial aneurysms. | https://www.wikidoc.org/index.php/FAM71D | |
d5e378b9b9a54be1c607e0889a743728780544a9 | wikidoc | FAM73B | FAM73B
The family with sequence similarity 73, member B, also known as FAM73B, is a human gene.
# Model organisms
Model organisms have been used in the study of FAM73B function. A conditional knockout mouse line, called Fam73btm1a(KOMP)Wtsi was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty four tests were carried out on mutant mice and six significant abnormalities were observed. Homozygous mutant animals had a decreased body weight, altered body composition, abnormal tooth morphology, hypoalbuminemia, decreased bone mineral content and strength, and an increased susceptibility to bacterial infection. | FAM73B
The family with sequence similarity 73, member B, also known as FAM73B, is a human gene.[1]
# Model organisms
Model organisms have been used in the study of FAM73B function. A conditional knockout mouse line, called Fam73btm1a(KOMP)Wtsi[10][11] was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.[12][13][14]
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.[8][15] Twenty four tests were carried out on mutant mice and six significant abnormalities were observed. Homozygous mutant animals had a decreased body weight, altered body composition, abnormal tooth morphology, hypoalbuminemia, decreased bone mineral content and strength, and an increased susceptibility to bacterial infection.[8] | https://www.wikidoc.org/index.php/FAM73B | |
5c58ebcc2b2bbf25cfa428051b47d4d199620315 | wikidoc | FAM76A | FAM76A
FAM76A is a protein that in Homo sapiens is encoded by the FAM76A gene. Notable structural characteristics of FAM76A include an 83 amino acid coiled coil domain as well as a four amino acid poly-serine compositional bias. FAM76A is conserved in most chordates but it is not found in other deuterostrome phlya such as echinodermata, hemichordata, or xenacoelomorpha—suggesting that FAM76A arose sometime after chordates in the evolutionary lineage. Furthermore, FAM76A is not found in fungi, plants, archaea, or bacteria. FAM76A is predicted to localize to the nucleus and may play a role in regulating transcription.
# Gene
## Location
FAM76A is located on the (+) strand of the short arm of chromosome 1 (1p35.3), with the genomic sequence starting at 27725979 and ending at 27762915. The coding region is made up of 3462 base pairs and is translated into 341 amino acids.
## Gene neighborhood
Genes that flank FAM76A on the telomeric side include IFI6, CHMP1AP1, and RPEP3, while genes that flank FAM76A on the centromeric side include STX12, PPP1R8, and L0C105376894.
## Common aliases
In Caenorhabditis elegans, FAM76A is referred to as K04F10.7. Outside of this, FAM76A does not have any significant alternative names.
# Mrna
In Homo sapiens, the FAM76A gene produces 9 different mRNAs, 7 of which are alternatively spliced and 2 of which are unspliced. Of the alternatively spliced mRNAs, isoform 1 is the longest variant of the gene and is the subject of this article.
# Protein
## General properties
The molecular weight of FAM76A is 38.4 kDa, making it possible for this protein to diffuse through nuclear pores. The isoelectric point is 9.28. FAM76A does not have any significant positive, negative, or mixed charge clusters. In addition, FAM76A does not have any predicted hydrophobic or transmembrane segments, suggesting that this protein is not found within the cell membrane.
## Composition
The amino acid composition of FAM76A protein showed amino acid frequencies within 1.5% of that of normal human proteins for all but cysteine, valine, and lysine. Cysteine and lysine have higher frequencies compared to a normal Homo sapiens protein, while valine has a lower frequency compared to a normal Homo sapiens protein. These same amino acid frequency differences are seen in FAM76A orthologs such as Gallus gallus (H. sapiens sequence identity 84%), Serinus canaria (H. sapiens sequence identity 77%), and Crassostrea gigas (H. sapiens sequence identity 57%).
## Domains and motifs
NCBI conserved domains search identified an uncharacterized conserved protein (YqiK) that contains the Band7/PHB/SPFH domain, whose function is unknown and is conserved in various species ranging from humans to bacteria. In Homo sapiens, the Band7/PHB/SPFH domain spans from amino acids 252-326. The molecular weight of this domain is 8.9 kDa, and it has an isoelectric point of 9.23. The Band7/PHB/SPFH domain does not have any amino acids frequency composition that differs from a normal Homo sapiens protein. This domain is yet to be assigned to any domain superfamily.
## Secondary structure
FAM76A is predicted to only have alpha helices. In total, there are 17 alpha helices predicted, the longest of which contains the Band7/PHB/SPFH domain. From this, only 8 alpha helices are located within conserved regions of FAM76A (see conceptual translation).
## Tertiary/quaternary structure
FAM76A contains a coiled-coil domain, which is located within the Band7/PHB/SPFH domain. No significant ligand-binding sites or active sites were predicted from I-TASSER. There is no evidence to suggest that FAM76A interacts with other proteins to form a quaternary structure.
## Sub-cellular localization
The protein subcellular localization prediction tool, PSORT II, predicts FAM76A to be located within the nucleus. This prediction is observed in orthologs such as Gallus gallus and Callorhinchus milii. Further evidence for FAM76A localizing to the nucleus is provided by the presence of a nuclear localization signal.
# Expression
According to NCBI Geo Profile, FAM76A is expressed in Homo sapiens parathyroid, lymph node, esophagus, and bone marrow tissue. Developmental stages where FAM76A expression is detected include the embryoid body, fetus, and adult.
## Brain atlas
Allen human brain atlas predictions for FAM76A expression are depicted below. FAM76A appears to have higher expression within the cerebral cortex and lower expression in parts of the reptilian brain such as the pontine tegmentum (see expression table for further details).
- Various brain views of FAM76A expression in Homo sapiens—green represents high expression, while red represents low expression
- Frontal view
Frontal view
- Caudal view
Caudal view
- Sagittal view
Sagittal view
## Experimental data
Select data from three experiments involving FAM76A are shown below. In one experiment, CLDN1 over-expression in lung adenocarcinoma cells decreased FAM76A expression. In another experiment, androgen insensitive prostate cancer cells were shown to have reduced expression of FAM76A compared to androgen sensitive cells. Another experiment demonstrated that metaphase II oocyte cells were shown to have more expression of FAM76A compared to control cells.
- Selected NCBI Geo Data
- FAM76A levels in H. sapiens lung adenocarcinoma cell lines were compared between cultures that had claudin-1 (CLDN1) overexpression and control cells
FAM76A levels in H. sapiens lung adenocarcinoma cell lines were compared between cultures that had claudin-1 (CLDN1) overexpression and control cells
- Expression of FAM76A in Homo sapiens androgen sensitive and insensitive prostate cancer cell lines
Expression of FAM76A in Homo sapiens androgen sensitive and insensitive prostate cancer cell lines
- FAM76A expression between H. sapiens metaphase II oocytes and control (consisting of a mixture of skeletal muscle, kidney, lung, colon, liver, spleen, breast, brain, heart, and stomach) cell lines
FAM76A expression between H. sapiens metaphase II oocytes and control (consisting of a mixture of skeletal muscle, kidney, lung, colon, liver, spleen, breast, brain, heart, and stomach) cell lines
# Regulation of expression
## Post-translational modifications
FAM76A is predicted to undergo a variety of post-translational modifications. Post-translational modifications found within conserved regions include 7 phosphorylation sites, 2 sumoylation sites, and 1 nuclear localization signal. These modifications indicate that FAM76A is localized to the nucleus. Refer to conceptual translation for a visual representation of the aforementioned modifications.
- Conceptual translation for FAM76A
- File:FAM76A conceptual translation .png
- File:FAM76A conceptual translation 2.png
- Conceptual translation key
Conceptual translation key
## Promoter
Genomatrix's ElDorado program predicts a promoter for FAM76A that is named GXP_71042 and is 679 base pairs. It is located on chromosome 1, starting at 27725479 and ending at 27726157. GXP_71042 overlaps with the start of the coding sequence of FAM76A. There are several transcription factors that bind to this promoter. Many of the transcription factors that bind to the promoter region of FAM76A have function dealing with blood cells, the immune system, and leukocytes—perhaps suggesting that FAM76A is involved in immune function. It would also appear that the most common matrix families include C2H2 zinc fingers and myeloid zinc fingers, suggesting that these matrix families may be heavily involved in FAM76A transcription.
## RNA binding proteins
Common RNA binding proteins within the 3’ UTR of FAM76A include PABPC1, ELAVL1, and PUM2—each with predicted binding frequencies of 32, 18, and 16 times, respectively.
# Interacting proteins
FAM76A was found to have a physical interaction with ELAVL1. The interaction was detected by immunoprecipitation by Abdelmohsen et al., 2009. ELAVL1 is involved in regulating gene expression.
# Homology/evolution
## Paralogs
FAM76B is a paralog of FAM76A. It is estimated that FAM76A and FAM76B diverged from each other around 17.5 MYA. Structural similarities that are conserved between FAM76A/B include a coiled coil domain as well as a poly serine compositional bias. FAM76A and FAM76B both exhibit high expression in tissues such as lymph node, whole blood, testis, ovary, brain, kidney, liver, and lung. FAM76B has about 62% sequence identity with FAM76A.
## Orthologs
Shown here is a table of a select number of orthologs for Homo sapiens FAM76A. The table includes closely, intermediately, and distantly related orthologs. Mammals are shown to have greater similarity, while aquatic vertebrates such as actinopterygii/chondrichthyes have lesser similarity. Orthologs of Homo sapiens protein FAM76A are listed above in descending order of date of divergence and then by sequence identity.
## Evolution
FAM76A appears to have a moderate rate of mutation when compared to fibrinogen (fast mutating) and cytochrome c (slow mutating). This suggests that FAM76A has been at least somewhat resistant to mutation during the course of evolution.
# Clinical significance
## Disease association
FAM76A expression is highest in adrenal tumors, esophageal tumors, and soft tissue/muscle tissue tumors. Copy number gain/loss of FAM76A—along with neighboring genes—has shown to produce detrimental phenotypes. In one case report, a patient with a copy number gain from 1p36.11-34.2 was shown to have developmental delays. Another patient, who had a copy number gain from 1p36.1-35, showed similar delays. In another case report, a patient with a copy number loss of 1p35.3, the exact location of FAM76A, developed macrocephaly.
# Multiple sequence alignment (MSA)
The MSA, shown below and generated with Biology Workbench CLUSTALW, arranges orthologs by the first letter of genus and then the first two letters of species. There are 3 domains that are highly conserved across orthologs. Two of these domains have an unknown function, while the third domain is a coiled-coil domain. Conservation of these regions was traced back to Cryptosporidium parvum Iowa II, which diverged from Homo sapiens 1724.7 MYA. Conserved region 1 contains mostly polar amino acids; conserved region 2 contains both polar and non-polar amino acids; and the coiled-coil domain contains mostly polar amino acids.
- Distant Ortholog Multiple Sequence Alignment of FAM76A
- File:FAM76A MSA1.png
- File:FAM76A MSA2.png
- Purple=Similar Amino Acid Chemistry Blue=Same Amino Acid
Purple=Similar Amino Acid ChemistryBlue=Same Amino Acid
- File:FAM76A MSA4.png | FAM76A
FAM76A is a protein that in Homo sapiens is encoded by the FAM76A gene.[1] Notable structural characteristics of FAM76A include an 83 amino acid coiled coil domain as well as a four amino acid poly-serine compositional bias.[2] FAM76A is conserved in most chordates but it is not found in other deuterostrome phlya such as echinodermata, hemichordata, or xenacoelomorpha—suggesting that FAM76A arose sometime after chordates in the evolutionary lineage. Furthermore, FAM76A is not found in fungi, plants, archaea, or bacteria.[3] FAM76A is predicted to localize to the nucleus and may play a role in regulating transcription.[4]
# Gene
## Location
FAM76A is located on the (+) strand of the short arm of chromosome 1 (1p35.3), with the genomic sequence starting at 27725979 and ending at 27762915. The coding region is made up of 3462 base pairs and is translated into 341 amino acids.[1][6]
## Gene neighborhood
Genes that flank FAM76A on the telomeric side include IFI6, CHMP1AP1, and RPEP3, while genes that flank FAM76A on the centromeric side include STX12, PPP1R8, and L0C105376894.[1]
## Common aliases
In Caenorhabditis elegans, FAM76A is referred to as K04F10.7.[7] Outside of this, FAM76A does not have any significant alternative names.
# Mrna
In Homo sapiens, the FAM76A gene produces 9 different mRNAs, 7 of which are alternatively spliced and 2 of which are unspliced. Of the alternatively spliced mRNAs, isoform 1 is the longest variant of the gene and is the subject of this article.[1]
# Protein
## General properties
The molecular weight of FAM76A is 38.4 kDa, making it possible for this protein to diffuse through nuclear pores.[8] The isoelectric point is 9.28. FAM76A does not have any significant positive, negative, or mixed charge clusters. In addition, FAM76A does not have any predicted hydrophobic or transmembrane segments, suggesting that this protein is not found within the cell membrane.[9]
## Composition
The amino acid composition of FAM76A protein showed amino acid frequencies within 1.5% of that of normal human proteins for all but cysteine, valine, and lysine. Cysteine and lysine have higher frequencies compared to a normal Homo sapiens protein, while valine has a lower frequency compared to a normal Homo sapiens protein. These same amino acid frequency differences are seen in FAM76A orthologs such as Gallus gallus (H. sapiens sequence identity 84%), Serinus canaria (H. sapiens sequence identity 77%), and Crassostrea gigas (H. sapiens sequence identity 57%).
## Domains and motifs
NCBI conserved domains search identified an uncharacterized conserved protein (YqiK) that contains the Band7/PHB/SPFH domain, whose function is unknown and is conserved in various species ranging from humans to bacteria.[6] In Homo sapiens, the Band7/PHB/SPFH domain spans from amino acids 252-326. The molecular weight of this domain is 8.9 kDa, and it has an isoelectric point of 9.23. The Band7/PHB/SPFH domain does not have any amino acids frequency composition that differs from a normal Homo sapiens protein.[9] This domain is yet to be assigned to any domain superfamily.
## Secondary structure
FAM76A is predicted to only have alpha helices. In total, there are 17 alpha helices predicted, the longest of which contains the Band7/PHB/SPFH domain.[10] From this, only 8 alpha helices are located within conserved regions of FAM76A (see conceptual translation).
## Tertiary/quaternary structure
FAM76A contains a coiled-coil domain, which is located within the Band7/PHB/SPFH domain. No significant ligand-binding sites or active sites were predicted from I-TASSER.[11] There is no evidence to suggest that FAM76A interacts with other proteins to form a quaternary structure.
## Sub-cellular localization
The protein subcellular localization prediction tool, PSORT II, predicts FAM76A to be located within the nucleus. This prediction is observed in orthologs such as Gallus gallus and Callorhinchus milii.[12] Further evidence for FAM76A localizing to the nucleus is provided by the presence of a nuclear localization signal.[4]
# Expression
According to NCBI Geo Profile, FAM76A is expressed in Homo sapiens parathyroid, lymph node, esophagus, and bone marrow tissue. Developmental stages where FAM76A expression is detected include the embryoid body, fetus, and adult.[13]
## Brain atlas
Allen human brain atlas predictions for FAM76A expression are depicted below. FAM76A appears to have higher expression within the cerebral cortex and lower expression in parts of the reptilian brain such as the pontine tegmentum (see expression table for further details).[14]
- Various brain views of FAM76A expression in Homo sapiens—green represents high expression, while red represents low expression
- Frontal view
Frontal view
- Caudal view
Caudal view
- Sagittal view
Sagittal view
## Experimental data
Select data from three experiments involving FAM76A are shown below. In one experiment, CLDN1 over-expression in lung adenocarcinoma cells decreased FAM76A expression.[15] In another experiment, androgen insensitive prostate cancer cells were shown to have reduced expression of FAM76A compared to androgen sensitive cells.[16] Another experiment demonstrated that metaphase II oocyte cells were shown to have more expression of FAM76A compared to control cells.[17]
- Selected NCBI Geo Data
- FAM76A levels in H. sapiens lung adenocarcinoma cell lines were compared between cultures that had claudin-1 (CLDN1) overexpression and control cells
FAM76A levels in H. sapiens lung adenocarcinoma cell lines were compared between cultures that had claudin-1 (CLDN1) overexpression and control cells
- Expression of FAM76A in Homo sapiens androgen sensitive and insensitive prostate cancer cell lines
Expression of FAM76A in Homo sapiens androgen sensitive and insensitive prostate cancer cell lines
- FAM76A expression between H. sapiens metaphase II oocytes and control (consisting of a mixture of skeletal muscle, kidney, lung, colon, liver, spleen, breast, brain, heart, and stomach) cell lines
FAM76A expression between H. sapiens metaphase II oocytes and control (consisting of a mixture of skeletal muscle, kidney, lung, colon, liver, spleen, breast, brain, heart, and stomach) cell lines
# Regulation of expression
## Post-translational modifications
FAM76A is predicted to undergo a variety of post-translational modifications. Post-translational modifications found within conserved regions include 7 phosphorylation sites, 2 sumoylation sites, and 1 nuclear localization signal.[18] These modifications indicate that FAM76A is localized to the nucleus. Refer to conceptual translation for a visual representation of the aforementioned modifications.
- Conceptual translation for FAM76A
- File:FAM76A conceptual translation .png
- File:FAM76A conceptual translation 2.png
- Conceptual translation key
Conceptual translation key
## Promoter
Genomatrix's ElDorado program predicts a promoter for FAM76A that is named GXP_71042 and is 679 base pairs. It is located on chromosome 1, starting at 27725479 and ending at 27726157. GXP_71042 overlaps with the start of the coding sequence of FAM76A.[19] There are several transcription factors that bind to this promoter. Many of the transcription factors that bind to the promoter region of FAM76A have function dealing with blood cells, the immune system, and leukocytes—perhaps suggesting that FAM76A is involved in immune function. It would also appear that the most common matrix families include C2H2 zinc fingers and myeloid zinc fingers, suggesting that these matrix families may be heavily involved in FAM76A transcription.
## RNA binding proteins
Common RNA binding proteins within the 3’ UTR of FAM76A include PABPC1, ELAVL1, and PUM2—each with predicted binding frequencies of 32, 18, and 16 times, respectively.[20]
# Interacting proteins
FAM76A was found to have a physical interaction with ELAVL1. The interaction was detected by immunoprecipitation by Abdelmohsen et al., 2009.[21] ELAVL1 is involved in regulating gene expression.
# Homology/evolution
## Paralogs
FAM76B is a paralog of FAM76A. It is estimated that FAM76A and FAM76B diverged from each other around 17.5 MYA.[1] Structural similarities that are conserved between FAM76A/B include a coiled coil domain as well as a poly serine compositional bias.[6] FAM76A and FAM76B both exhibit high expression in tissues such as lymph node, whole blood, testis, ovary, brain, kidney, liver, and lung.[22] FAM76B has about 62% sequence identity with FAM76A.[6]
## Orthologs
Shown here is a table of a select number of orthologs for Homo sapiens FAM76A. The table includes closely, intermediately, and distantly related orthologs. Mammals are shown to have greater similarity, while aquatic vertebrates such as actinopterygii/chondrichthyes have lesser similarity. Orthologs of Homo sapiens protein FAM76A are listed above in descending order of date of divergence and then by sequence identity.
## Evolution
FAM76A appears to have a moderate rate of mutation when compared to fibrinogen (fast mutating) and cytochrome c (slow mutating).[3][23] This suggests that FAM76A has been at least somewhat resistant to mutation during the course of evolution.
# Clinical significance
## Disease association
FAM76A expression is highest in adrenal tumors, esophageal tumors, and soft tissue/muscle tissue tumors.[1][24] Copy number gain/loss of FAM76A—along with neighboring genes—has shown to produce detrimental phenotypes. In one case report, a patient with a copy number gain from 1p36.11-34.2 was shown to have developmental delays.[25] Another patient, who had a copy number gain from 1p36.1-35, showed similar delays.[26] In another case report, a patient with a copy number loss of 1p35.3, the exact location of FAM76A, developed macrocephaly.[26]
# Multiple sequence alignment (MSA)
The MSA, shown below and generated with Biology Workbench CLUSTALW, arranges orthologs by the first letter of genus and then the first two letters of species.[9] There are 3 domains that are highly conserved across orthologs. Two of these domains have an unknown function, while the third domain is a coiled-coil domain. Conservation of these regions was traced back to Cryptosporidium parvum Iowa II, which diverged from Homo sapiens 1724.7 MYA. Conserved region 1 contains mostly polar amino acids; conserved region 2 contains both polar and non-polar amino acids; and the coiled-coil domain contains mostly polar amino acids.
- Distant Ortholog Multiple Sequence Alignment of FAM76A
- File:FAM76A MSA1.png
- File:FAM76A MSA2.png
- Purple=Similar Amino Acid Chemistry Blue=Same Amino Acid
Purple=Similar Amino Acid ChemistryBlue=Same Amino Acid
- File:FAM76A MSA4.png | https://www.wikidoc.org/index.php/FAM76A | |
fc75161de64a02d021cf5d423428f8ea2d8ec967 | wikidoc | FAM83A | FAM83A
Protein FAM83A (family member with sequence similarity 83) also known as tumor antigen BJ-TSA-9 is a protein that in humans is encoded by the FAM83A gene.
This protein is predicted to contain one domain of unknown function 1669 (DUF1669), which places this protein into the PLDc_SuperFamily. It has been linked to be a potential biomarker in lung, prostate, and bladder cancers.
# Gene
FAM83A is located on chromosome 8, locus q24.13, and spans 27,566 base pairs. There is a promoter approximately 4,000 base pairs upstream as predicted by the tool ElDorado by Genomatix. Deletions in this part of the chromosome, including the FAM83A gene, often result in Langer-Giedion syndrome.
# mRNA
The FAM83A mRNA has 10 different splice forms, with transcript variant 1 being the subject of this article. This mRNA consists of approximately 2,900 base pairs. It contains a domain of unknown function 1669 (DUF1669), and is a member of the PLDc_SF superfamily. It has been placed into this superfamily based on highly similar sequences between FAM83A and other N-terminus phospholipase D-like domains; however, it's missing the functional histidine and therefore only predicted to have a similar structure. Four exons comprise this mRNA. Predictions show several possible RNA stem loop formations in the untranslated regions of the mRNA.
# Protein
The FAM83A gene encodes for the FAM83A protein isoform A. This protein is 434 amino acids in length, and weighs approximately 45 kiloDaltons. Although the structure is not confirmed, it is predicted using GOR4 to have four alpha helices and five beta sheets, with an isoelectric point of 8.964 There appears to be no signal peptide and is not a transmembrane protein. Using CBLAST, it was observed to share a common sequence with the protein 3H0G, however, not in the predicted functional region of FAM83A. This may still provide valuable information, though, on a possible partial structure for this protein.
# Expression
FAM83A is expressed in many different areas of the human body, and at very different levels. EST data suggests that this gene is expressed primarily in adults. It shows significant levels in the mouth and larynx, with other raised expression in the prostate, lung, and esophagus. These normal levels are even more elevated in head and neck tumors, lung tumors, prostate cancers, and bladder carcinomas. Microarray expression data also show different environmental conditions, especially irritants. Such irritants can be cigarette smoke, where FAM83A has been shown to increase expression after 24 hours exposure, and house dust mite extract on bronchial epithelial cells, where FAM83A expression also increases after exposure. FAM83A shows decreased expression when activating transcription factor 2 (ATF2) is knocked out. Since ATF2 was not predicted to bind in the promoter region, it suggests that there is an indirect relationship between FAM83A and ATF2. With increased expression to irritants and allergens along with an indirect relationship with ATF2, it suggests FAM83A may be in a signaling pathway.
# Cancer
There are multiple studies that link FAM83A overexpression to lung, prostate, and bladder cancers. Researchers believe that this gene might make a good candidate for early detection of these cancers, especially lung cancer. It is unknown why or how FAM83A is upregulated. Studies have shown that arsenic can acetylate the promoter causing upregulation, suggesting this may be a similar mechanism to how this gene becomes unregulated in cancer.
# Protein interaction
FAM83A has been shown to interact with palate, lung, and nasal epithelium carcinoma associated protein (PLUNC) through the STRING tool. This information gathered came from textmining information dealing with cancer.
# Homology
FAM83A appears to be a relatively new gene, with BLAST and BLAT only showing orthology back through bony fishes. It is highly conserved through its relatives The DUF1669 domain is the most highly conserved region of the protein, with areas outside of it being more variable. Below is a table of orthologs, noting that this is not a comprehensive list: | FAM83A
Protein FAM83A (family member with sequence similarity 83) also known as tumor antigen BJ-TSA-9 is a protein that in humans is encoded by the FAM83A gene.[1]
This protein is predicted to contain one domain of unknown function 1669 (DUF1669), which places this protein into the PLDc_SuperFamily.[1][2][3] It has been linked to be a potential biomarker in lung, prostate, and bladder cancers.[4][5][6]
# Gene
FAM83A is located on chromosome 8, locus q24.13,[1] and spans 27,566 base pairs.[1] There is a promoter approximately 4,000 base pairs upstream as predicted by the tool ElDorado by Genomatix.[7] Deletions in this part of the chromosome, including the FAM83A gene, often result in Langer-Giedion syndrome.[8]
# mRNA
The FAM83A mRNA has 10 different splice forms,[9] with transcript variant 1 being the subject of this article. This mRNA consists of approximately 2,900 base pairs. It contains a domain of unknown function 1669 (DUF1669), and is a member of the PLDc_SF superfamily.[10] It has been placed into this superfamily based on highly similar sequences between FAM83A and other N-terminus phospholipase D-like domains; however, it's missing the functional histidine and therefore only predicted to have a similar structure.[3] Four exons comprise this mRNA.[1][11] Predictions show several possible RNA stem loop formations in the untranslated regions of the mRNA.[12]
# Protein
The FAM83A gene encodes for the FAM83A protein isoform A.[1] This protein is 434 amino acids in length, and weighs approximately 45 kiloDaltons.[13] Although the structure is not confirmed, it is predicted using GOR4 to have four alpha helices and five beta sheets,[14] with an isoelectric point of 8.964[12] There appears to be no signal peptide[15] and is not a transmembrane protein.[16] Using CBLAST, it was observed to share a common sequence with the protein 3H0G,[17] however, not in the predicted functional region of FAM83A. This may still provide valuable information, though, on a possible partial structure for this protein.
# Expression
FAM83A is expressed in many different areas of the human body, and at very different levels.[18] EST data suggests that this gene is expressed primarily in adults. It shows significant levels in the mouth and larynx, with other raised expression in the prostate, lung, and esophagus.[18] These normal levels are even more elevated in head and neck tumors, lung tumors, prostate cancers, and bladder carcinomas.[18] Microarray expression data also show different environmental conditions, especially irritants. Such irritants can be cigarette smoke, where FAM83A has been shown to increase expression after 24 hours exposure,[19] and house dust mite extract on bronchial epithelial cells, where FAM83A expression also increases after exposure.[20] FAM83A shows decreased expression when activating transcription factor 2 (ATF2) is knocked out.[21] Since ATF2 was not predicted to bind in the promoter region, it suggests that there is an indirect relationship between FAM83A and ATF2. With increased expression to irritants and allergens along with an indirect relationship with ATF2, it suggests FAM83A may be in a signaling pathway.
# Cancer
There are multiple studies that link FAM83A overexpression to lung, prostate, and bladder cancers. Researchers believe that this gene might make a good candidate for early detection of these cancers, especially lung cancer.[4][5] It is unknown why or how FAM83A is upregulated. Studies have shown that arsenic can acetylate the promoter causing upregulation, suggesting this may be a similar mechanism to how this gene becomes unregulated in cancer.[6]
# Protein interaction
FAM83A has been shown to interact with palate, lung, and nasal epithelium carcinoma associated protein (PLUNC) through the STRING tool.[22] This information gathered came from textmining information dealing with cancer.[5]
# Homology
FAM83A appears to be a relatively new gene, with BLAST and BLAT only showing orthology back through bony fishes.[11][23] It is highly conserved through its relatives[23] The DUF1669 domain is the most highly conserved region of the protein, with areas outside of it being more variable. Below is a table of orthologs, noting that this is not a comprehensive list: | https://www.wikidoc.org/index.php/FAM83A | |
6da66f3ec182aec66f72d9c986330a47e26a9333 | wikidoc | FAM83H | FAM83H
FAM83H is a gene in humans that encodes a protein known as FAM83H (uncharacterized protein FAM83H). FAM83H is targeted for the nucleus and it predicted to play a role in the structural development and calcification of tooth enamel.
# Gene
## Location
FAM83H is located on the long arm of chromosome 8 (8q24.3), starting at 143723933 and ending at 143738030. The FAM83H gene spans 14097 base pairs and is orientated on the—strand. The coding region is made up of 5,604 base pairs and 5 exons.
## Expression
FAM83H is ubiquitously expressed throughout the human body at relatively low levels.
## Transcript Variants
In humans, there is only one known major product of the FAM83H gene.
# Homology
## Paralogs
There are no paralogs of FAM83H
## Orthologs
Below is a table of a variety of orthologs of the human FAM83H. The table include closely, intermediately and distantly related orthologs.
Orthologs of the human protein FAM83H are listed above in descending order or date of divergence and then ascending order of percent identity. FAM83H is highly conserved throughout all orthologs, this is demonstrated with a 40% identity in the least similar ortholog. FAM83H has evolved slowly and evenly over time.
# Protein
## General Properties
The molecular weight of FAM83H is 127.1kD and contains 1179 amino acids. The isoelectric point is 6.52. There are no significant positive or negative charge clusters in the protein. There is a stretch of 21 0’s from 254-275 and a stretch of 24 0’s from 420-444.1
## Composition
FAM83H is proline rich, being 10.32% protein, and is asparagine deficient with only 1.1%. The percent composition of each amino acid is fairly consistent throughout the orthologs of the protein. The most distant ortholog displays the most variance in amino acid composition.
## Domains
FAM83H has two known domains. The PLDc_FAM83H (phospholipase like domain) domain stretches from 17-281 on FAM83H. It lacks the functionally important histidine, so while it may share similar structure it most likely lacks PLD activity. The MIP-T3 microtubule binding domain stretches from 909-1176.
## Post-translational modifications
FAM83H is highly phosphorylated post modification. There are 11 predicted phosphorylated sites. There are two motifs with high probability of post translational modification sumoylation sites. Sumoylation sites are involved in a number of cellular processes, including nuclear-cytosolic transport, transcriptional regulation and protein stability. FAM83H does not have a signal peptide
## Secondary Structure
Fam83H is primarily composed of alpha helices and random coils. Alpha helices comprise the majority of the protein. There is a transmembrane domain from 231-252.
## Subcellular Localization
Protein FAM83H is targeted to the nucleus.
## Interacting Proteins
FAM83H was found to interact with WDR72 and MMP20. MMP20 is responsible for the breakdown of extracellular matrix and plays a role in tissue remodeling in ameloblasts. mutations in WDR72 is thought to play a role in amelogenesis imperfecta
# Clinical Significance
## Disease Association
People who suffer from amelogenesis imperfecta have lost function in FAM83H. | FAM83H
FAM83H is a gene in humans that encodes a protein known as FAM83H (uncharacterized protein FAM83H). FAM83H is targeted for the nucleus and it predicted to play a role in the structural development and calcification of tooth enamel.
# Gene
## Location
FAM83H is located on the long arm of chromosome 8 (8q24.3), starting at 143723933 and ending at 143738030. The FAM83H gene spans 14097 base pairs and is orientated on the—strand. The coding region is made up of 5,604 base pairs and 5 exons.[1]
## Expression
FAM83H is ubiquitously expressed throughout the human body at relatively low levels.[2][3]
## Transcript Variants
In humans, there is only one known major product of the FAM83H gene.[4][5][6]
# Homology
## Paralogs
There are no paralogs of FAM83H[7]
## Orthologs
Below is a table of a variety of orthologs of the human FAM83H. The table include closely, intermediately and distantly related orthologs.
Orthologs of the human protein FAM83H are listed above in descending order or date of divergence and then ascending order of percent identity. FAM83H is highly conserved throughout all orthologs, this is demonstrated with a 40% identity in the least similar ortholog. FAM83H has evolved slowly and evenly over time.[8][9]
# Protein
## General Properties
The molecular weight of FAM83H is 127.1kD and contains 1179 amino acids. The isoelectric point is 6.52. There are no significant positive or negative charge clusters in the protein. There is a stretch of 21 0’s from 254-275 and a stretch of 24 0’s from 420-444.1 [10]
## Composition
FAM83H is proline rich, being 10.32% protein, and is asparagine deficient with only 1.1%. The percent composition of each amino acid is fairly consistent throughout the orthologs of the protein. The most distant ortholog displays the most variance in amino acid composition.
## Domains
FAM83H has two known domains. The PLDc_FAM83H (phospholipase like domain) domain stretches from 17-281 on FAM83H. It lacks the functionally important histidine, so while it may share similar structure it most likely lacks PLD activity. The MIP-T3 microtubule binding domain stretches from 909-1176.[11]
## Post-translational modifications
FAM83H is highly phosphorylated post modification. There are 11 predicted phosphorylated sites. There are two motifs with high probability of post translational modification sumoylation sites. Sumoylation sites are involved in a number of cellular processes, including nuclear-cytosolic transport, transcriptional regulation and protein stability. FAM83H does not have a signal peptide
## Secondary Structure
Fam83H is primarily composed of alpha helices and random coils. Alpha helices comprise the majority of the protein. There is a transmembrane domain from 231-252.[12][13]
## Subcellular Localization
Protein FAM83H is targeted to the nucleus.[14]
## Interacting Proteins
FAM83H was found to interact with WDR72 and MMP20.[15] MMP20 is responsible for the breakdown of extracellular matrix and plays a role in tissue remodeling in ameloblasts. mutations in WDR72 is thought to play a role in amelogenesis imperfecta
# Clinical Significance
## Disease Association
People who suffer from amelogenesis imperfecta have lost function in FAM83H.[16][17] | https://www.wikidoc.org/index.php/FAM83H | |
1c99384a8dab8d8af39b80fc5cc2e4607f552286 | wikidoc | FAM98A | FAM98A
Family with sequence similarity 98, member A, or FAM98A, is a gene that in the human genome encodes the FAM98A protein. FAM98A has two paralogs in humans, FAM98B and FAM98C. All three are characterized by DUF2465, a conserved domain shown to bind to RNA. FAM98A is also characterized by a glycine-rich C-terminal domain. FAM98A also has homologs in vertebrates and invertebrates and has distant homologs in choanoflagellates and green algae.
# Gene
## Locus
The FAM98A gene is located on 2p22.3 in humans on the "-" (minus) strand. Including the 5' and 3' UTR, the gene spans 15,634 bases and contains 8 exons.
## mRNA
The mRNA is 2745bp, comprising the 8 exons. The coding sequence starts at base 75 and continues until base 1631. The polyA tail signal sequence is a six-nucleotide sequence 20 bases from the 3' end of the transcript at base 2725-2730, and the polyA site is at base 2745.
# Protein
## Primary Sequence
FAM98A is 518 amino acids in length with a molecular weight of 55.3 kDa, without modifications. Residues 10-329 comprise the DUF2465, and the remainder of the protein is a diglycine-rich C terminus. Glycine makes up approximately 20% of the protein, with the majority of these in the last 200 residues.
## Post-Translational Modifications
FAM98A has six strongly predicted phosphorylation sites in DUF2465. These sites are predicted to phosphorylate S169, T178, S236, T243, S276, and S285 by protein kinase C. GPS also predicts phosphorylation by protein kinase C at S285 and T178.
FAM98A is likely sumoylated at K183 and K195. Sumoylation may allow the cell to re-localize FAM98A between the nucleus and the cytoplasm. The glycine-rich C terminus has repeat GRG sequences, which has been shown to be susceptible to methylation of the arginine, either symmetrically or asymmetrically. Another paper explains the effects of arginine methylation on biochemical functions such as transcription activation and repression, mRNA splicing, nuclear-cytosolic shuttling, and DNA repair.
## Secondary Structure
The N terminus is predicted to have multiple alpha helices, though the C terminus likely is only coiled. The alpha helices do not form any channel, and FAM98A is not a transmembrane protein.
## Tertiary and Quaternary Structure
The structure of FAM98A was predicted with the program Phyre2. The N-terminal region contains several alpha helices, and a C-terminal coiled region corresponding to the glycine-rich C terminus. These two regions of the protein are connected by an alpha helix approximately 50 residues long from the residues 200-256. Phyre2 found the most similar protein to be the human protein NDC80 kinetochore complex component, a nuclear protein that binds to microtubules.
## Domains and Motifs
FAM98A has a domain of unknown function 2465 (DUF2465) from the amino acids 10-329. Within the DUF2465, there is a heptide (VPDRGGR) near the C-terminal end that is conserved in all species tested. The C-terminal end is a glycine-rich domain (glycine makes up about 40% of the C terminus) with GGRGGR repeats. At residues 149-155, there is a predicted nuclear export signal, with the sequence ICIALGM (generally -X--X--X-). Residues 173-176 are predicted to be a nuclear localization signal KKLK (K--X-).
# Homology
## Paralogs
FAM98A has two paralogs: FAM98B and FAM98C. FAM98A is longest of the three paralogous protein products with 518 amino acids. It is more similar to FAM98B, whose glycine-rich C terminus is much shorter than FAM98A. FAM98C less similar than FAM98B to FAM98A, all but lacking in a C terminus after DUF2465, as well as containing more differences in the amino acid sequence within the DUF2465. All three protein products have been shown experimentally to associate non-specifically with RNA: FAM98A binds to mRNA and FAM98B is incorporated into a tRNA-splicing complex.
## Orthologs
Orthologs for FAM98A have been found in vertebrates. In insects and molluscs, there are predicted proteins for a FAM98A gene. Because there are three paralogs of FAM98 in humans, there is a common ancestor of these genes. A strict ortholog, a gene that is orthologous to FAM98A and not the entire FAM98 family, is less clear. FAM98A has not yet been thoroughly studied, compounded with the fact that many genomes are yet to be recorded, makes it more difficult to determine if the predicted FAM98A gene in mosquitoes is a strict ortholog (the split of FAM98 into FAM98A,B,C occurred before the species diverged) or if it is a homolog ("FAM98A" in mosquitoes is the ancestral FAM98 gene).
## Distant Homologs
Genes homologous to FAM98A are predicted to occur in many taxa within Animalia, but there are other taxa outside of Animalia that may have homologous FAM98 genes in their genomes. Eukaryotes such as the opisthokonts Monosiga brevicollis (XP_00174505.1) and Capraspora owczarzaki (XP_004346371.1), and even the protist Chlorella variabilis (XP_005845167.1), a green alga, may contain FAM98 in their genomes.
## Homologous Domains
The homologous domain in FAM98A is the DUF2465 (Domain of Unknown Function 2465) domain. The function of this domain, like the gene itself, is largely unknown, though it has been reported that it preferentially binds to RNA, targeting mRNA in FAM98A and tRNA in FAM98B.
# Expression
## Promoter
The promoter (GXP_90934) assigned to the human FAM98A transcript (GXT_24436545) is 915 bp long, and it overlaps with the transcript to include 243 bp of mRNA transcript. Nuclear respiratory factor 1 (NRF1) is a transcription factor that had seven sites predicted to bind on the promoter, four of which had a Matrix similarity - optimum score of greater than or equal to 0.085 and the two highest scoring transcription factors predicted were NRF1 with scores of 0.204 and 0.199.
## Expression
In a GEO large-scale human transcriptome, FAM98A was ubiquitously expressed, though not uniformly expressed. Cell types that were most highly expressed were many parts of the brain (cortex, amygdala, thalamus, corpus callosum, and pituitary gland), the testis, uterus, and smooth muscle. According to Aceview, FAM98A is expressed at 3.9 times the expression of the average gene.
Eleven transcripts have been identified by AceView, five of which were "good", complete (both N and C termini fully translated) proteins. From the transcripts, there are apparently two main parts of FAM98A: the first four exons and the second four exons, and these parts correspond roughly to the tertiary structure of the protein - the N-terminal alpha-helices to exons 1-4, and the long alpha-helical arm and C terminus coils to exons 5-8.
# Function and Biochemistry
The function of FAM98A has not been experimentally determined, though it has been shown to bind its DUF2465 with mRNA. Kiraga et al. have noted that basic proteins bind with nucleic acids. In fact, FAM98A (and it orthologs) have an unmodified isoelectric point of approximately 9.
# Known Interactions
FAM98A has been experimentally shown to interact with UBC, DDX1, C14orf166, and SUMO3, and it is coexpressed with DDX1, C14orf166, and RBM25. These latter three proteins interact with mRNA, as FAM98A is also predicted to do. DDX1 is a putative ATP-dependent RNA helicase in a spliceosome, likely releasing the RNA from the splicing complex. C14orf166 is a polymerase II binding factor, and RBM25 regulates alternative splicing. All of these interactions suggest that FAM98A is a nuclear protein. FAM98A also interacts with SUMO3, which sumoylates lysines in the protein to facilitate transport across the nuclear membrane between the nucleus and cytosol. FAM98A also binds nonspecific mRNA indicating a potential mRNA shuttle out of the nucleus to the ribosomes.
# Clinical Significance
In a study that looked at differences in expression levels of certain genes (including FAM98A) in both young and old men with high or low protein diets, the expression levels were measured as a ratio of low/high protein diets in each group of men (young and old). FAM98A had increased expression in low protein diets in both young and old men, 1.01 and 1.20, respectively. Only one other gene in the study had the same trend of increased expression in lower protein diets in both groups: THOC4. THOC4, THO Complex 4 or Aly/REF export factor, dimerizes to form a larger complex and chaperones spliced mRNA, assisting with processing and export of the mRNA. The paper mentions that up-regulation of mRNA in older individuals is associated with RNA binding/splicing, signaling proteins, and protein degradation; in fact, the older group has the higher expression of FAM98A in low protein diets than the younger men.
# Disease Association
Research on a population in Taiwan has found an association between young onset hypertension and two SNPs upstream of four genes at the locus 2p22.3. One of these four genes was FAM98A, though more research must be done to verify that it was FAM98A that was the gene responsible for the hypertension. Indeed, FAM98A is expressed moderately high (roughly the 75th percentile) in smooth muscle and cardiac myocytes. | FAM98A
Family with sequence similarity 98, member A, or FAM98A, is a gene that in the human genome encodes the FAM98A protein. FAM98A has two paralogs in humans, FAM98B and FAM98C. All three are characterized by DUF2465, a conserved domain shown to bind to RNA.[1] FAM98A is also characterized by a glycine-rich C-terminal domain.[2] FAM98A also has homologs in vertebrates and invertebrates and has distant homologs in choanoflagellates and green algae.
# Gene
## Locus
The FAM98A gene is located on 2p22.3 in humans on the "-" (minus) strand. Including the 5' and 3' UTR, the gene spans 15,634 bases and contains 8 exons.[3]
## mRNA
The mRNA is 2745bp, comprising the 8 exons. The coding sequence starts at base 75 and continues until base 1631. The polyA tail signal sequence is a six-nucleotide sequence 20 bases from the 3' end of the transcript at base 2725-2730, and the polyA site is at base 2745.[4]
# Protein
## Primary Sequence
FAM98A is 518 amino acids in length with a molecular weight of 55.3 kDa, without modifications. Residues 10-329 comprise the DUF2465, and the remainder of the protein is a diglycine-rich C terminus. Glycine makes up approximately 20% of the protein, with the majority of these in the last 200 residues.[5]
## Post-Translational Modifications
FAM98A has six strongly predicted phosphorylation sites in DUF2465. These sites are predicted to phosphorylate S169, T178, S236, T243, S276, and S285 by protein kinase C.[6] GPS also predicts phosphorylation by protein kinase C at S285 and T178.[7]
FAM98A is likely sumoylated at K183 and K195.[8] Sumoylation may allow the cell to re-localize FAM98A between the nucleus and the cytoplasm.[9] The glycine-rich C terminus has repeat GRG sequences, which has been shown to be susceptible to methylation of the arginine, either symmetrically or asymmetrically.[10] Another paper explains the effects of arginine methylation on biochemical functions such as transcription activation and repression, mRNA splicing, nuclear-cytosolic shuttling, and DNA repair.[11]
## Secondary Structure
The N terminus is predicted to have multiple alpha helices, though the C terminus likely is only coiled.[12] The alpha helices do not form any channel, and FAM98A is not a transmembrane protein.
## Tertiary and Quaternary Structure
The structure of FAM98A was predicted with the program Phyre2. The N-terminal region contains several alpha helices, and a C-terminal coiled region corresponding to the glycine-rich C terminus. These two regions of the protein are connected by an alpha helix approximately 50 residues long from the residues 200-256. Phyre2 found the most similar protein to be the human protein NDC80 kinetochore complex component, a nuclear protein that binds to microtubules.[13]
## Domains and Motifs
FAM98A has a domain of unknown function 2465 (DUF2465) from the amino acids 10-329. Within the DUF2465, there is a heptide (VPDRGGR) near the C-terminal end that is conserved in all species tested. The C-terminal end is a glycine-rich domain (glycine makes up about 40% of the C terminus) with GGRGGR repeats.[5] At residues 149-155, there is a predicted nuclear export signal, with the sequence ICIALGM (generally [LIVFM]-X-[LIVFM]-X-[LIVFM]-X-[LIVFM]).[14] Residues 173-176 are predicted to be a nuclear localization signal KKLK (K-[K/R]-X-[K/R]).[15]
# Homology
## Paralogs
FAM98A has two paralogs: FAM98B and FAM98C. FAM98A is longest of the three paralogous protein products with 518 amino acids. It is more similar to FAM98B, whose glycine-rich C terminus is much shorter than FAM98A. FAM98C less similar than FAM98B to FAM98A, all but lacking in a C terminus after DUF2465, as well as containing more differences in the amino acid sequence within the DUF2465. All three protein products have been shown experimentally to associate non-specifically with RNA: FAM98A binds to mRNA and FAM98B is incorporated into a tRNA-splicing complex.[1]
## Orthologs
Orthologs for FAM98A have been found in vertebrates. In insects and molluscs, there are predicted proteins for a FAM98A gene. Because there are three paralogs of FAM98 in humans, there is a common ancestor of these genes. A strict ortholog, a gene that is orthologous to FAM98A and not the entire FAM98 family, is less clear. FAM98A has not yet been thoroughly studied, compounded with the fact that many genomes are yet to be recorded, makes it more difficult to determine if the predicted FAM98A gene in mosquitoes is a strict ortholog (the split of FAM98 into FAM98A,B,C occurred before the species diverged) or if it is a homolog ("FAM98A" in mosquitoes is the ancestral FAM98 gene).
## Distant Homologs
Genes homologous to FAM98A are predicted to occur in many taxa within Animalia, but there are other taxa outside of Animalia that may have homologous FAM98 genes in their genomes. Eukaryotes such as the opisthokonts Monosiga brevicollis (XP_00174505.1) and Capraspora owczarzaki (XP_004346371.1), and even the protist Chlorella variabilis (XP_005845167.1), a green alga, may contain FAM98 in their genomes.[16]
## Homologous Domains
The homologous domain in FAM98A is the DUF2465 (Domain of Unknown Function 2465) domain. The function of this domain, like the gene itself, is largely unknown, though it has been reported that it preferentially binds to RNA, targeting mRNA in FAM98A and tRNA in FAM98B.[1]
# Expression
## Promoter
The promoter (GXP_90934) assigned to the human FAM98A transcript (GXT_24436545)[17] is 915 bp long, and it overlaps with the transcript to include 243 bp of mRNA transcript. Nuclear respiratory factor 1 (NRF1) is a transcription factor that had seven sites predicted to bind on the promoter, four of which had a Matrix similarity - optimum score of greater than or equal to 0.085 and the two highest scoring transcription factors predicted were NRF1 with scores of 0.204 and 0.199.[18]
## Expression
In a GEO large-scale human transcriptome, FAM98A was ubiquitously expressed, though not uniformly expressed. Cell types that were most highly expressed were many parts of the brain (cortex, amygdala, thalamus, corpus callosum, and pituitary gland), the testis, uterus, and smooth muscle.[19] According to Aceview, FAM98A is expressed at 3.9 times the expression of the average gene.
Eleven transcripts have been identified by AceView, five of which were "good", complete (both N and C termini fully translated) proteins. From the transcripts, there are apparently two main parts of FAM98A: the first four exons and the second four exons, and these parts correspond roughly to the tertiary structure of the protein - the N-terminal alpha-helices to exons 1-4, and the long alpha-helical arm and C terminus coils to exons 5-8.[20]
# Function and Biochemistry
The function of FAM98A has not been experimentally determined, though it has been shown to bind its DUF2465 with mRNA.[1] Kiraga et al. have noted that basic proteins bind with nucleic acids.[21] In fact, FAM98A (and it orthologs) have an unmodified isoelectric point of approximately 9.[22]
# Known Interactions
FAM98A has been experimentally shown to interact with UBC, DDX1, C14orf166, and SUMO3, and it is coexpressed with DDX1, C14orf166, and RBM25.[23] These latter three proteins interact with mRNA, as FAM98A is also predicted to do. DDX1 is a putative ATP-dependent RNA helicase in a spliceosome, likely releasing the RNA from the splicing complex.[24] C14orf166 is a polymerase II binding factor,[25] and RBM25 regulates alternative splicing.[26] All of these interactions suggest that FAM98A is a nuclear protein. FAM98A also interacts with SUMO3, which sumoylates lysines in the protein to facilitate transport across the nuclear membrane between the nucleus and cytosol.[9] FAM98A also binds nonspecific mRNA indicating a potential mRNA shuttle out of the nucleus to the ribosomes.[1]
# Clinical Significance
In a study that looked at differences in expression levels of certain genes (including FAM98A) in both young and old men with high or low protein diets, the expression levels were measured as a ratio of low/high protein diets in each group of men (young and old). FAM98A had increased expression in low protein diets in both young and old men, 1.01 and 1.20, respectively. Only one other gene in the study had the same trend of increased expression in lower protein diets in both groups: THOC4.[27] THOC4, THO Complex 4 or Aly/REF export factor, dimerizes to form a larger complex and chaperones spliced mRNA, assisting with processing and export of the mRNA.[28] The paper mentions that up-regulation of mRNA in older individuals is associated with RNA binding/splicing, signaling proteins, and protein degradation; in fact, the older group has the higher expression of FAM98A in low protein diets than the younger men.[27]
# Disease Association
Research on a population in Taiwan has found an association between young onset hypertension and two SNPs upstream of four genes at the locus 2p22.3. One of these four genes was FAM98A, though more research must be done to verify that it was FAM98A that was the gene responsible for the hypertension.[29] Indeed, FAM98A is expressed moderately high (roughly the 75th percentile) in smooth muscle and cardiac myocytes.[19] | https://www.wikidoc.org/index.php/FAM98A | |
3a5745b206cc49cdb78a0d197236658255619473 | wikidoc | FANCD2 | FANCD2
Fanconi anemia group D2 protein is a protein that in humans is encoded by the FANCD2 gene. The Fanconi anemia complementation group (FANC) currently includes FANCA, FANCB, FANCC, FANCD1 (also called BRCA2), FANCD2 (this gene), FANCE, FANCF, FANCG, and FANCL.
# Function
Fanconi anemia is a genetically homozygous recessive disorder characterized by chromosomal instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group D2. This protein is monoubiquitinated in response to DNA damage, resulting in its localization to nuclear foci with other proteins (BRCA1 and BRCA2) involved in homology-directed DNA repair (see Figure: Recombinational repair of DNA double-strand damages). A nuclear complex containing FANCA, FANCC, FANCF and FANCG proteins is required for the activation of the FANCD2 protein to the mono-ubiquitinated isoform. Mono-ubiquination of FANCD2 is essential for repairing DNA interstrand crosslinks.
Mono-ubiquitination is also required for interaction with the nuclease FAN1. FAN1 recruitment and its consequent activity restrain DNA replication fork progression and prevent chromosome abnormalities from occurring when DNA replication forks stall. Alternative splicing results in two transcript variants encoding different isoforms.
# Infertility
Humans with a FANCD deficiency display hypogonadism, male infertility, impaired spermatogenesis, and reduced female fertility. Similarly, mice deficient in FANCD2 show hypogonadism, impaired fertility and impaired gametogenesis.
In the non-mutant mouse, FANCD2 is expressed in spermatogonia, pre-leptotene spermatocytes, and in spermatocytes in the leptotene, zygotene and early pachytene stages of meiosis. In synaptonemal complexes of meiotic chromosomes, activated FANCD2 protein co-localizes with BRCA1 (breast cancer susceptibility protein). FANCD2 mutant mice exhibit chromosome mis-pairing during the pachytene stage of meiosis and germ cell loss. Activated FANCD2 protein may normally function prior to the initiation of meiotic recombination, perhaps to prepare chromosomes for synapsis, or to regulate subsequent recombination events.
# Clinical significance
Tobacco smoke suppresses the expression of FANCD2, which codes for a DNA damage "caretaker" or repair mechanism.
## Cancer
FANCD2 mutant mice have a significantly increased incidence of tumors including ovarian, gastric and hepatic adenomas as well as hepatocellular, lung, ovarian and mammary carcinomas. Humans with a FANCD2 deficiency have increased acute myeloid leukemia, and squamous cell carcinomas (head and neck squamous cell carcinomas and anogenital carcinomas).
# Interactions
FANCD2 has been shown to interact with:
- FANCI
- Ataxia telangiectasia mutated,
- BARD1,
- BRCA1.
- BRCA2,
- FANCE,
- HTATIP, and
- MEN1. | FANCD2
Fanconi anemia group D2 protein is a protein that in humans is encoded by the FANCD2 gene.[1][2][3][4] The Fanconi anemia complementation group (FANC) currently includes FANCA, FANCB, FANCC, FANCD1 (also called BRCA2), FANCD2 (this gene), FANCE, FANCF, FANCG, and FANCL.
# Function
Fanconi anemia is a genetically homozygous recessive disorder characterized by chromosomal instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group D2. This protein is monoubiquitinated in response to DNA damage, resulting in its localization to nuclear foci with other proteins (BRCA1 and BRCA2) involved in homology-directed DNA repair (see Figure: Recombinational repair of DNA double-strand damages). A nuclear complex containing FANCA, FANCC, FANCF and FANCG proteins is required for the activation of the FANCD2 protein to the mono-ubiquitinated isoform.[12] Mono-ubiquination of FANCD2 is essential for repairing DNA interstrand crosslinks.
Mono-ubiquitination is also required for interaction with the nuclease FAN1. FAN1 recruitment and its consequent activity restrain DNA replication fork progression and prevent chromosome abnormalities from occurring when DNA replication forks stall.[13] Alternative splicing results in two transcript variants encoding different isoforms.[4]
# Infertility
Humans with a FANCD deficiency display hypogonadism, male infertility, impaired spermatogenesis, and reduced female fertility. Similarly, mice deficient in FANCD2 show hypogonadism, impaired fertility and impaired gametogenesis.[14]
In the non-mutant mouse, FANCD2 is expressed in spermatogonia, pre-leptotene spermatocytes, and in spermatocytes in the leptotene, zygotene and early pachytene stages of meiosis.[15] In synaptonemal complexes of meiotic chromosomes, activated FANCD2 protein co-localizes with BRCA1 (breast cancer susceptibility protein).[12] FANCD2 mutant mice exhibit chromosome mis-pairing during the pachytene stage of meiosis and germ cell loss.[16] Activated FANCD2 protein may normally function prior to the initiation of meiotic recombination, perhaps to prepare chromosomes for synapsis, or to regulate subsequent recombination events.[12]
# Clinical significance
Tobacco smoke suppresses the expression of FANCD2, which codes for a DNA damage "caretaker" or repair mechanism.[3]
## Cancer
FANCD2 mutant mice have a significantly increased incidence of tumors including ovarian, gastric and hepatic adenomas as well as hepatocellular, lung, ovarian and mammary carcinomas.[14][16] Humans with a FANCD2 deficiency have increased acute myeloid leukemia, and squamous cell carcinomas (head and neck squamous cell carcinomas and anogenital carcinomas).[14]
# Interactions
FANCD2 has been shown to interact with:
- FANCI[17][18]
- Ataxia telangiectasia mutated,[19][20]
- BARD1,[21]
- BRCA1.[20][21]
- BRCA2,[22][23][24]
- FANCE,[23][25][26]
- HTATIP,[24] and
- MEN1.[27] | https://www.wikidoc.org/index.php/FANCD2 | |
1d6f4dfeb28b43cde9e32d085b1f82d5176e54d4 | wikidoc | FBLIM1 | FBLIM1
Filamin-binding LIM protein 1 is a protein that in humans is encoded by the FBLIM1 gene.
This gene encodes a protein with an N-terminal filamin-binding domain, a central proline-rich domain, and, multiple C-terminal LIM domains. This protein localizes at cell junctions and may link cell adhesion structures to the actin cytoskeleton. This protein may be involved in the assembly and stabilization of actin-filaments and likely plays a role in modulating cell adhesion, cell morphology and cell motility. This protein also localizes to the nucleus and may affect cardiomyocyte differentiation after binding with the CSX/NKX2-5 transcription factor. Alternative splicing results in multiple transcript variants encoding different isoforms.
# Interactions
FBLIM1 has been shown to interact with Filamin, PLEKHC1 and FLNB. | FBLIM1
Filamin-binding LIM protein 1 is a protein that in humans is encoded by the FBLIM1 gene.[1][2][3]
This gene encodes a protein with an N-terminal filamin-binding domain, a central proline-rich domain, and, multiple C-terminal LIM domains. This protein localizes at cell junctions and may link cell adhesion structures to the actin cytoskeleton. This protein may be involved in the assembly and stabilization of actin-filaments and likely plays a role in modulating cell adhesion, cell morphology and cell motility. This protein also localizes to the nucleus and may affect cardiomyocyte differentiation after binding with the CSX/NKX2-5 transcription factor. Alternative splicing results in multiple transcript variants encoding different isoforms.[3]
# Interactions
FBLIM1 has been shown to interact with Filamin,[4] PLEKHC1[1] and FLNB.[5] | https://www.wikidoc.org/index.php/FBLIM1 | |
98d614316b9e1b2ee0925d0ba429f7e7db0fd571 | wikidoc | FBXO11 | FBXO11
F-box only protein 11 is a protein that in humans is encoded by the FBXO11 gene.
# Function
This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene.
FBXO11 is conserved from nematodes to mammals, and both human FBXO11 and its worm ortholog (DRE-1) form functional SCF ubiquitin ligase complexes. By binding to and mediating the degradation of its substrate proteins, FBXO11 plays important roles in regulating cell cycle regulation, tumorigenesis, and tumor cell metastasis. Well established targets of FBXO11 include BCL6, and Snail.
# Clinical significance
Inactivation of FBXO11-mediated BCL6 degradation has been shown to contribute to abnormal germinal-center formation and tumorigenesis. The Caenorhabditis elegans DRE-1/FBXO11 was reported to target the conserved transcription factor BLMP-1 for proteasomal degradation, and thereby regulates developmental timing and maturation. The gene encoding FBXO11 was found to be deleted or mutated in multiple diffuse large B cell lymphoma (DLBCL) cell lines, and this inactivation of FBXO11 contributes to increased levels BCL6 and subsequently DLBCL pathogenesis. FBXO11 mutations were also identified in other human cancers, such as colon, lung, ovary, and head and neck tumors. In mice, a homozygous mutation of FBXO11 results in cleft palate defects, facial clefting, and perinatal lethality. Moreover, haploinsufficient mutant alleles cause otitis media, a disorder that affects approximately 15% of children. | FBXO11
F-box only protein 11 is a protein that in humans is encoded by the FBXO11 gene.[1][2][3][4]
# Function
This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene.[4]
FBXO11 is conserved from nematodes to mammals, and both human FBXO11 and its worm ortholog (DRE-1) form functional SCF ubiquitin ligase complexes. By binding to and mediating the degradation of its substrate proteins, FBXO11 plays important roles in regulating cell cycle regulation, tumorigenesis, and tumor cell metastasis. Well established targets of FBXO11 include BCL6,[5][6][7] and Snail.[8]
# Clinical significance
Inactivation of FBXO11-mediated BCL6 degradation has been shown to contribute to abnormal germinal-center formation and tumorigenesis.[9] The Caenorhabditis elegans DRE-1/FBXO11 was reported to target the conserved transcription factor BLMP-1 for proteasomal degradation, and thereby regulates developmental timing and maturation.[10] The gene encoding FBXO11 was found to be deleted or mutated in multiple diffuse large B cell lymphoma (DLBCL) cell lines, and this inactivation of FBXO11 contributes to increased levels BCL6 and subsequently DLBCL pathogenesis.[5] FBXO11 mutations were also identified in other human cancers, such as colon, lung, ovary, and head and neck tumors. In mice, a homozygous mutation of FBXO11 results in cleft palate defects, facial clefting, and perinatal lethality. Moreover, haploinsufficient mutant alleles cause otitis media, a disorder that affects approximately 15% of children.[11] | https://www.wikidoc.org/index.php/FBXO11 | |
263262ceb6901ba46d5259a21327b44ddfc1fa8a | wikidoc | FBXO31 | FBXO31
F-box only protein 31 is a protein that in humans is encoded by the FBXO31 gene.
# Function
Members of the F-box protein family, such as FBXO31, are characterized by an approximately 40-amino acid F-box motif. SCF complexes, formed by SKP1 (MIM 601434), cullin (see CUL1; MIM 603134), and F-box proteins, act as protein-ubiquitin ligases. F-box proteins interact with SKP1 through the F box, and they interact with ubiquitination targets through other protein interaction domains.
F-box protein FBXO31 directs degradation of MDM2 to facilitate p53-mediated growth arrest following genotoxic stress. the F-box protein FBXO31, a candidate tumor suppressor encoded in 16q24.3 for which there is loss of heterozygosity in various solid tumors, is responsible for promoting MDM2 degradation. Following genotoxic stress, FBXO31 is phosphorylated by the DNA damage serine/threonine kinase ATM, resulting in increased levels of FBXO31. FBXO31 then interacts with and directs the degradation of MDM2, which is dependent on phosphorylation of MDM2 by ATM. FBXO31-mediated loss of MDM2 leads to elevated levels of p53, resulting in growth arrest. In cells depleted of FBXO31, MDM2 is not degraded and p53 levels do not increase following genotoxic stress. Thus, FBXO31 is essential for the classic robust increase in p53 levels following DNA damage. | FBXO31
F-box only protein 31 is a protein that in humans is encoded by the FBXO31 gene.[1]
# Function
Members of the F-box protein family, such as FBXO31, are characterized by an approximately 40-amino acid F-box motif. SCF complexes, formed by SKP1 (MIM 601434), cullin (see CUL1; MIM 603134), and F-box proteins, act as protein-ubiquitin ligases. F-box proteins interact with SKP1 through the F box, and they interact with ubiquitination targets through other protein interaction domains.[2][1]
F-box protein FBXO31 directs degradation of MDM2 to facilitate p53-mediated growth arrest following genotoxic stress. the F-box protein FBXO31, a candidate tumor suppressor encoded in 16q24.3 for which there is loss of heterozygosity in various solid tumors, is responsible for promoting MDM2 degradation. Following genotoxic stress, FBXO31 is phosphorylated by the DNA damage serine/threonine kinase ATM, resulting in increased levels of FBXO31. FBXO31 then interacts with and directs the degradation of MDM2, which is dependent on phosphorylation of MDM2 by ATM. FBXO31-mediated loss of MDM2 leads to elevated levels of p53, resulting in growth arrest. In cells depleted of FBXO31, MDM2 is not degraded and p53 levels do not increase following genotoxic stress. Thus, FBXO31 is essential for the classic robust increase in p53 levels following DNA damage.[3] | https://www.wikidoc.org/index.php/FBXO31 | |
d77f3bbde1b86538fcdb7d81eb212ebbc7172588 | wikidoc | FBXW11 | FBXW11
βTrCP2 (also known as Fbxw11 or HOS) is a protein that in humans is encoded by the BTRC (beta-transducin repeat containing) gene.
This gene encodes a member of the F-box protein family which is characterized by an approximately 40 residue structural motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (Skp1-Cul1-F-box protein), which often, but not always, recognize substrates in a phosphorylation-dependent manner. F-box proteins are divided into 3 classes:
- Fbxws containing WD40 repeats,
- Fbxls containing leucine-rich repeats,
- and Fbxos containing either "other" protein-protein interaction modules or no recognizable motifs.
The protein encoded by FBXW11 belongs to the Fbxw class as, in addition to an F-box, this protein contains multiple WD40 repeats. This protein is homologous to Xenopus βTrCP, yeast Met30, Neurospora Scon2 and Drosophila Slimb. In mammals, in addition to βTrCP2, a paralog protein (called βTrCP1 or FBXW1) also exists, but, so far, their functions appear redundant and indistinguishable.
# Discovery
Human βTrCP (referred to both βTrCP1 and βTrCP2) was originally identified as a cellular ubiquitin ligase that is bound by the HIV-1 Vpu viral protein to eliminate cellular CD4 by connecting it to the proteolytic machinery. Subsequently, βTrCP was shown to regulate multiple cellular processes by mediating the degradation of various targets. Cell cycle regulators constitute a major group of βTrCP substrates. During S phase, βTrCP keeps CDK1 in check by promoting the degradation of the phosphatase CDC25A, whereas in G2, βTrCP contributes to CDK1 activation by targeting the kinase WEE1 for degradation. In early mitosis, βTrCP mediates the degradation of EMI1, an inhibitor of the APC/C ubiquitin ligase complex, which is responsible for the anaphase-metaphase transition (by inducing the proteolysis of Securin) and mitotic exit (by driving the degradation of mitotic CDK1 activating cyclin subunits). Furthermore, βTrCP controls APC/C by targeting REST, thereby removing its transcriptional repression on MAD2, an essential component of the spindle assembly checkpoint that keeps APC/C inactive until all chromatids are attached to the spindle microtubles.
# Functions
βTrCP plays important roles in regulating cell cycle checkpoints. In response to genotoxic stress, it contributes to turn off CDK1 activity by mediating the degradation of CDC25A in collaboration with Chk1, thereby preventing cell cycle progression before the completion of DNA repair. During recovery from DNA replication and DNA damage, βTrCP instead targets Claspin in a Plk1-dependent manner.
βTrCP has also emerged as an important player in protein translation, cell growth and survival. In response to mitogens, PDCD4, an inhibitor of the translation initiation factor eIF4A, is rapidly degraded in a βTrCP- and S6K1-dependent manner, allowing efficient protein translation and cell growth. βTrCP also cooperates with mTOR and CK1α to induce the degradation of DEPTOR (an mTOR inhibitor), thereby generating an auto-amplification loop to promote the full activation of mTOR. At the same time, βTrCP mediates the degradation of the pro-apoptotic protein BimEL to promote cell survival.
βTrCP also associates with phosphorylated IkappaBalpha and beta-catenin destruction motifs, probably functioning in multiple transcriptional programs by regulating the NF-kappaB and the WNT pathways.
# Interactions
BTRC (gene) has been shown to interact with:
- FBXW11
- DLG1
- IκBα
- NFKB2
- RELA
- SKP1A
- CDC34
- CUL1
- β-catenin
- WEE1
- EMI1
- Cdc25A
- Claspin
- REST
- PDCD4
- DEPTOR
# Clinical Significance
βTrCP behaves as an oncoprotein in some tissues. Elevated levels of βTrCP expression have been found in colorectal, pancreatic, hapatoblastoma, and breast cancers. | FBXW11
βTrCP2 (also known as Fbxw11 or HOS) is a protein that in humans is encoded by the BTRC (beta-transducin repeat containing) gene.[1][2]
This gene encodes a member of the F-box protein family which is characterized by an approximately 40 residue structural motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (Skp1-Cul1-F-box protein), which often, but not always, recognize substrates in a phosphorylation-dependent manner. F-box proteins are divided into 3 classes:
- Fbxws containing WD40 repeats,
- Fbxls containing leucine-rich repeats,
- and Fbxos containing either "other" protein-protein interaction modules or no recognizable motifs.
The protein encoded by FBXW11 belongs to the Fbxw class as, in addition to an F-box, this protein contains multiple WD40 repeats. This protein is homologous to Xenopus βTrCP, yeast Met30, Neurospora Scon2 and Drosophila Slimb. In mammals, in addition to βTrCP2, a paralog protein (called βTrCP1 or FBXW1) also exists, but, so far, their functions appear redundant and indistinguishable.
# Discovery
Human βTrCP (referred to both βTrCP1 and βTrCP2) was originally identified as a cellular ubiquitin ligase that is bound by the HIV-1 Vpu viral protein to eliminate cellular CD4 by connecting it to the proteolytic machinery.[3] Subsequently, βTrCP was shown to regulate multiple cellular processes by mediating the degradation of various targets.[4] Cell cycle regulators constitute a major group of βTrCP substrates. During S phase, βTrCP keeps CDK1 in check by promoting the degradation of the phosphatase CDC25A,[5] whereas in G2, βTrCP contributes to CDK1 activation by targeting the kinase WEE1 for degradation.[6] In early mitosis, βTrCP mediates the degradation of EMI1,[7][8] an inhibitor of the APC/C ubiquitin ligase complex, which is responsible for the anaphase-metaphase transition (by inducing the proteolysis of Securin) and mitotic exit (by driving the degradation of mitotic CDK1 activating cyclin subunits). Furthermore, βTrCP controls APC/C by targeting REST, thereby removing its transcriptional repression on MAD2, an essential component of the spindle assembly checkpoint that keeps APC/C inactive until all chromatids are attached to the spindle microtubles.[9]
# Functions
βTrCP plays important roles in regulating cell cycle checkpoints. In response to genotoxic stress, it contributes to turn off CDK1 activity by mediating the degradation of CDC25A in collaboration with Chk1,[5][10] thereby preventing cell cycle progression before the completion of DNA repair. During recovery from DNA replication and DNA damage, βTrCP instead targets Claspin in a Plk1-dependent manner.[11][12][13]
βTrCP has also emerged as an important player in protein translation, cell growth and survival. In response to mitogens, PDCD4, an inhibitor of the translation initiation factor eIF4A, is rapidly degraded in a βTrCP- and S6K1-dependent manner, allowing efficient protein translation and cell growth.[14] βTrCP also cooperates with mTOR and CK1α to induce the degradation of DEPTOR (an mTOR inhibitor), thereby generating an auto-amplification loop to promote the full activation of mTOR.[15][16][17] At the same time, βTrCP mediates the degradation of the pro-apoptotic protein BimEL to promote cell survival.[18]
βTrCP also associates with phosphorylated IkappaBalpha and beta-catenin destruction motifs, probably functioning in multiple transcriptional programs by regulating the NF-kappaB and the WNT pathways.[19][20]
# Interactions
BTRC (gene) has been shown to interact with:
- FBXW11[21]
- DLG1[22]
- IκBα[21][23]
- NFKB2[24][25]
- RELA[23]
- SKP1A[3][21][26][27][28]
- CDC34[26][29]
- CUL1[21][26][27]
- β-catenin[20][30]
- WEE1[6]
- EMI1[7][8]
- Cdc25A[5][10]
- Claspin[11][12][13]
- REST[9][31]
- PDCD4[14]
- DEPTOR[15][16][17]
# Clinical Significance
βTrCP behaves as an oncoprotein in some tissues. Elevated levels of βTrCP expression have been found in colorectal,[32] pancreatic,[33] hapatoblastoma,[34] and breast cancers.[35] | https://www.wikidoc.org/index.php/FBXW11 | |
331b16cc9f4b8f3462dc052ce7a7bf6f4bb68538 | wikidoc | FERMT3 | FERMT3
Fermitin family homolog 3) (FERMT3), also known as kindlin-3 (KIND3), MIG2-like protein (MIG2B), or unc-112-related protein 2 (URP2) is a protein that in humans is encoded by the FERMT3 gene. The kindlin family of proteins, member of the B4.1 superfamily, comprises three conserved protein homologues, kindlin 1, 2, and 3. They each contain a bipartite FERM domain comprising four subdomains F0, F1, F2, and F3 that show homology with the FERM head (H) domain of the cytoskeletal Talin protein. Kindlins have been linked to Kindler syndrome, leukocyte adhesion deficiency, cancer and other acquired human diseases. They are essential in the organisation of focal adhesions that mediate cell-extracellular matrix junctions and are involved in other cellular compartments that control cell-cell contacts and nucleus functioning. Therefore, they are responsible for cell to cell crosstalk via cell-cell contacts and integrin mediated cell adhesion through focal adhesion proteins and as specialised adhesion structures of hematopoietic cells they are also present in podosome's F actin surrounding ring structure. Isoform 2 may act as a repressor of NF-kappa-B and apoptosis
# Evolution
It has been suggested that the evolutionary source of a single ancestral Kindlin protein is the earliest metazoa, the Parazoa. Within vertebrates, these ancestral proteins were subjected to duplication processes in order to arrive at the actual Kindlin family. In comparison with other members of the B4.1 superfamily of proteins, the FERM domains in Kindlin homologues have a greater degree of conservation. The presence of an inserted pleckstrin homology domain within the FERM domain, suggests that the metazoan evolution of the FERM domain is the origination from a proto-talin protein in unicellular or proto-multicellular organisms.
# Function
The FERMT3 protein has a key role in the regulation of hemostasis and thrombosis. This protein may also help maintain the membrane skeleton of erythrocytes. Kindlin 3 is a cytoskeletal signalling protein involved in the activation of the glycoprotein receptor, integrin. Together with the Talin protein it binds cooperatively to beta integrin’s cytoplasmic domain causing tail reorientation, thus altering the molecule’s conformation. Modification of integrin’s conformation serves to dissociate alpha and beta subunits by disrupting their interactions and helping the molecule adopt a high affinity state. FERMT3 functions as a stabilizer of the cytoskeleton and regulates its dynamics in cell and organelle motility.
# Clinical significance
FERMT3 mutations can result in autosomal recessive leukocyte adhesion deficiency syndrome-III (LAD-III). a deficiency in beta1, beta2 and beta3 integrin activation in platelets and leukocytes that causes haemorrhaging and recurrent infections. Loss of FERMT3 expression in leukocytes compromises their adhesion to the inflamed endothelia and affects neutrophil granulocyte binding and spreading while selectin mediated rolling is unaffected. It has also been found that FERMT3 lowers Natural Killer cell’s activation threshold, such that a loss of FERMT3 affects single receptor activation of NK cell-mediated cytotoxicity but has no impact on multiple receptors, where the protein deficiency is overcome and target cells are killed.
FERMT3 deficiency on β(2) integrin function depend on both cell type (Natural killer cell or Leukocytes) and the integrin activation stimulus. The prevention of the beta-3 activation is specifically related to LAD-3, causing Glanzmann's thrombasthenia symptoms, a condition in which patients bleed excessively. Leukocyte adhesion deficiency is diagnosed clinically and by complete blood counts that reveal leukocytosis with neutrophilia. Management and treatment of this disease aim to control these recurrent infections by antibiotics and blood transfusions, with bone marrow transplantation as the only curative measure. Failure to express the FERMT3 protein disrupts the ability to form clots and coagulate by preventing integrin αIIβ3-mediated platelet aggregation. | FERMT3
Fermitin family homolog 3) (FERMT3), also known as kindlin-3 (KIND3), MIG2-like protein (MIG2B), or unc-112-related protein 2 (URP2) is a protein that in humans is encoded by the FERMT3 gene.[1][2][3] The kindlin family of proteins, member of the B4.1 superfamily, comprises three conserved protein homologues, kindlin 1, 2, and 3. They each contain a bipartite FERM domain comprising four subdomains F0, F1, F2, and F3 that show homology with the FERM head (H) domain of the cytoskeletal Talin protein. Kindlins have been linked to Kindler syndrome, leukocyte adhesion deficiency, cancer and other acquired human diseases. They are essential in the organisation of focal adhesions that mediate cell-extracellular matrix junctions and are involved in other cellular compartments that control cell-cell contacts and nucleus functioning. Therefore, they are responsible for cell to cell crosstalk via cell-cell contacts and integrin mediated cell adhesion through focal adhesion proteins and as specialised adhesion structures of hematopoietic cells they are also present in podosome's F actin surrounding ring structure. Isoform 2 may act as a repressor of NF-kappa-B and apoptosis[4]
# Evolution
It has been suggested that the evolutionary source of a single ancestral Kindlin protein is the earliest metazoa, the Parazoa. Within vertebrates, these ancestral proteins were subjected to duplication processes in order to arrive at the actual Kindlin family. In comparison with other members of the B4.1 superfamily of proteins, the FERM domains in Kindlin homologues have a greater degree of conservation.[5] The presence of an inserted pleckstrin homology domain within the FERM domain, suggests that the metazoan evolution of the FERM domain is the origination from a proto-talin protein in unicellular or proto-multicellular organisms.[5][6]
# Function
The FERMT3 protein has a key role in the regulation of hemostasis and thrombosis.[6] This protein may also help maintain the membrane skeleton of erythrocytes.[1] Kindlin 3 is a cytoskeletal signalling protein involved in the activation of the glycoprotein receptor, integrin.[7] Together with the Talin protein it binds cooperatively to beta integrin’s cytoplasmic domain causing tail reorientation, thus altering the molecule’s conformation.[citation needed] Modification of integrin’s conformation serves to dissociate alpha and beta subunits by disrupting their interactions and helping the molecule adopt a high affinity state.[5] FERMT3 functions as a stabilizer of the cytoskeleton and regulates its dynamics in cell and organelle motility.[8][non-primary source needed]
# Clinical significance
FERMT3 mutations can result in autosomal recessive leukocyte adhesion deficiency syndrome-III (LAD-III).[1] a deficiency in beta1, beta2 and beta3 integrin activation in platelets and leukocytes that causes haemorrhaging and recurrent infections.[6] Loss of FERMT3 expression in leukocytes compromises their adhesion to the inflamed endothelia and affects neutrophil granulocyte binding and spreading while selectin mediated rolling is unaffected.[non-primary source needed] It has also been found that FERMT3 lowers Natural Killer cell’s activation threshold, such that a loss of FERMT3 affects single receptor activation of NK cell-mediated cytotoxicity but has no impact on multiple receptors, where the protein deficiency is overcome and target cells are killed.[non-primary source needed]
FERMT3 deficiency on β(2) integrin function depend on both cell type (Natural killer cell or Leukocytes) and the integrin activation stimulus.[9] The prevention of the beta-3 activation is specifically related to LAD-3, causing Glanzmann's thrombasthenia symptoms, a condition in which patients bleed excessively.[10][non-primary source needed] Leukocyte adhesion deficiency is diagnosed clinically and by complete blood counts that reveal leukocytosis with neutrophilia.[9] Management and treatment of this disease aim to control these recurrent infections by antibiotics and blood transfusions, with bone marrow transplantation as the only curative measure.[non-primary source needed] Failure to express the FERMT3 protein disrupts the ability to form clots and coagulate by preventing integrin αIIβ3-mediated platelet aggregation.[6] | https://www.wikidoc.org/index.php/FERMT3 | |
7070f93ed3836c188d8379ae9dbaf82039df3469 | wikidoc | FIP1L1 | FIP1L1
Factor interacting with PAPOLA and CPSF1 (i.e, FIP1L1; also termed Pre-mRNA 3'-end-processing factor FIP1) is a protein that in humans is encoded by the FIP1L1 gene (also known as Rhe, FIP1, and hFip1). An medically important aspect of the FIP1L1 gene is its fusion with other genes to form fusion genes which cause clonal hypereosinophilia and leukemic diseases in humans.
# Gene
The human FIP1L1 gene is located on chromosome 4 at position q12 (4q12), contains 19 exons, and codes for a complete protein consisting of 594 amino acids. However, alternative splicing of its Precursor mRNA results in multiple transcript variants encoding distinct FIP1L1 protein isoforms. The FIP1L1 gene is found in a wide range of species, being designated as FIP1 in Saccharomyces cerevisiae (yeast) and fip1l1 in coho salmon as well as mice and numerous other mammalian species.
In humans, an interstitial chromosomal deletion of about 800 kilobases at 4q12 deletes the CHIC2 gene (i.e.cysteine rich hydrophobic domain 2 gene) to create an in-frame fusion of the FIP1L1 gene with the platelet-derived growth factor receptor alpha gene (PGDFRA) gene. The product of PDGFRA, platelet-derived growth factor receptor alpha (PDGFRA), is a tyrosine kinase receptor of the RTK class III. When bound by its proper ligand, Platelet-derived growth factor (PDGF), it ] becomes active in phosphorylating proteins that, among other functions, promote cell growth and proliferation. (The FIP1L1-PDGFRA mutation was the first description of a gain of function mutation resulting from an interstitial deletion instead of a chromosomal translocation.) The FIP1L1-PDGFRA fusion gene consists of the 5'-end of FIP1L1 united to the 3'-end of PGDFRA at variable breakpoints in both genes extending over a 40 kilobase region in FIP1L1 and a small region of exon 12 in PDGFRA. The fusion gene may produce a protein consisting of the first 233 amino acids of FIP1L1 joined to the last 523 amino acids of PDGFRA or fused proteins consisting of other FIP1L1 and PDGFRA amino acid lengths. The known FIP1L1-PDGFRA fusion proteins exhibit similar if not identical pathological activities.
A Chromosomal translocation of FIP1L1 (4q12) with the Retinoic acid receptor alpha gene, i.e. RARA, (17q12) at various points yields a (15;17)(q22;q21) fusion gene, FIP1L1-RARA that also has been implicated in the development of human leukemic diseases in three case reports.
# FIPL1 function
FIP1L1 is a subunit of the cleavage and polyadenylation specificity factor subunit 1 (CPSF1) complex that polyadenylates the 3' end of precursor mRNAs (pre-mRNA) (see CPSF). The FIP1 motif of 40 amino acids on FIP1L1 is responsible for its binding to CPSF1. CPSF1 is an RNA processing protein that binds to uracil-rich sequences in pre-mRNA, concurrently binds with and stimulates POPOLA, i.e. Polynucleotide adenylyltransferase, and then proceeds to add adenylyl residues to pre-mRNA. This poly-adenylyl action increases pre-mRNA's maturation and movement from the nucleus to cytoplasm while also increasing the stability of the mRNA formed from pre-mRNA: FIP1L1 is a Pre-mRNA 3'-end-processing factor. FIP1L1 gene fusions between it and either the platelet-derived growth factor receptor, alpha (PGDFRA) or Retinoic acid receptor alpha (RARA) genes are causes of certain human diseases associated with pathologically increased levels of blood eosinophils and/or Leukemias.
# FIP1L1-PDGFRA fusion genes
## Expression
FIP1L1-PDGFRA fusion genes have been detected in the eosinophils, neutrophils, mast cells, monocytes, T lymphocytes, and B lymphocytes involved in hemtalogical malignancies. This suggests that the initial underlying genetic defect in these malignancies can begin in myeloid or lymphoid progenitor cells or in precursors to these myeloid and lymphoid progenitor cells. In the majority of instances, this fusion appears in and promotes the proliferation and differentiation of myeloid precursor cells along the eosinophil linage. In other cases, however, the fusion, while occurring in myeloid precursor cells, promotes proliferation and differentiation of precursor cells along the neutrophil linage or, less commonly, occurs in lymphoid precursor cells to promote the proliferation and differentiation of precursor cells along the lymphoid lineage.
## Function
FIP1L1-PDGFRA fusion proteins retain PDGFRA-related Tyrosine kinase activity but, unlike PDGFRA, their tyrosine kinase is constitutive, i.e. continuously active: the fusion proteins lack the intact protein's 3'-end that includes its juxtamembrane domain which normally blocks tyrosine kinase activity unless PDGFRA is bound to its activating ligand, platelet-derived growth factor. FIP1L1-PDGFRA fusion proteins are also resistant to PDGFRA's normal pathway of degradation, i.e. Proteasome-dependent ubiquitnation. In consequence, they are highly stable, long-lived, unregulated, and continuously express the stimulating actions of their PDGFRA tyrosine kinase component. In consequence, cells expressing FIP1L1-PDGFRA fusion proteins differentiate and proliferate along eosinophil, other granulocyte, or T lymphocyte lineages and bearers of these mutations suffer either: a) chronic eosinophilia which may progress to hypereosinophilia, the hypereosinophilic syndrome, and chronic eosinophilic leukemia; b) a type of myeloproliferative neoplasm/myeloblastic leukemia not distinguished by eosinophilia; or c) T-lymphoblastic leukemia/lymphoma. At least one case of FIP1L1-PDGFRA-induced disesae presented as a myeloid sarcoma with eosinophilia has been reported. (i.e. These pathological proliferation and differentiation responses are due to the unabated activity of the fusion proteins' tyrosine kinase in phosphorylating and thereby activating certain proteins that promote these functions. For example, in vitro studies show that a FIP1L1-PDGFRA fusion gene stimulates CD34+ cells to proliferate and differentiate along the eosinophil lineage by causing the activation of NF-κB, STAT5, and Protein kinase B cell signaling pathways. The FIP1L1 component of FIP1L1-PDGFRA is required for the fusion protein to activate STAT4 and protein kinase B.
## Clinical aspects
### Incidence
The age-adjusted incidence of hypereosinophilic syndrome/chronic eosinophilic leukemia reported by the International Classification of Diseases for Oncology (Version 3) is ~0.036 per 100,000 with the mean frequency of FIP1L1-PDGFRA gene fusions occurring in ~10% of patients with hypereosinophilia as detected in developed countries. The fused gene occurs with a male/female ratio of 1.47; the reason for this male predominance is not known. The fusion gene has been found in people of all age groups but only rarely in infants and children.
### Presentation
The ~70% of patients with the FIP1L1-PDGFRA fusion gene (also termed the F/P fusion gene) and marked eosinophilia commonly complain of weakness and malaise. They may also present with or have a history of signs and/or symptoms that are due to the damaging actions of tissue-infiltrating eosinophils such as: skin rashes or erythema; eosinophilic myocarditis (i.e. heart disease which may manifest as coronary artery disease, heart failure due to injured cardiac muscle, restrictive cardiomyopathy due to cardiac fibrosis, or blockage of arteries due to the embolization of blood clots that from in the heart); pulmonary airway and parenchymal disease; eosinophilic gastroenteritis; eosinophilic esophagitis; and dysfunction of other organs targeted by eosinophils. The ~30% of patients in whom the fusion gene effects non-eosinophilic granulocyte or lymphoid cell linages present with signs and symptoms respectively of acute myeloid leukemia or lymphoma T-lymphoblastic leukemia/lymphoma or lymphocytic leukemia.
### Diagnosis
Patients expressing the eosinophil-driving fusion protein typically present with hypereosinophilia arbitrarily define as blood cell counts containing greater than 1.5x109/liter eosinophils that have persisted for more than 6 months. However, lower levels of eosinophil counts and/or eosinophilia with a shorter history of duration are not a counter-indication of the diagnoses. These patients also exhibit elevations in their serum levels of Vitamin B12 and tryptase. Elevations of serum VitaminB12 and tryptase are seen regularly in systemic mastocytosis, a disease which may also present with eosinophilia and must be distinguished from FIP1L1-PDGFRA-induced diseases because of the very different treatments for the two types of diseases. Bone marrow examination may reveal increases in eosinophils and mast cells but usually does not contain elevated numbers of precursor cells or cells with microscopically visible chromosome abnormalities. This examination may be useful in excluding other malignant diseases associated with eosinophilia such as acute myeloid leukemia but does not give definitive results indicating FIP1L1-PDGFRA-induced disease. Rather, definitive results are obtained by detecting the presence of the FIP1L1-PDGFRA fusion gene in the blood and/or bone marrow cells of sufferers by cytogenic analysis using Fluorescence in situ hybridization or nested Reverse transcription polymerase chain reaction testing. Non-eosinophilic forms of FIP1L1-PDGFRA fusion gene-induced diseases are suggested by the presence of morphologically abnormal or excessive numbers of myeloid or lymphoid cells in the blood or bone marrow and, with respect to the lymphoid variants, by the presence of lymphadenopathy and/or lymphoma masses; ultimately, these variants also require demonstration of the FIP1L1-PDGFRA fusion genes fr diagnosis.
### Treatment
FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases, unlike most other diseases involving hypereosinophilia, are typically resistant to corticosteroid therapy. However, and unlike most cases of myeloid leukemia, FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases (including a case presenting with myeloid sarcoma) have been treated with great success and long term remissions using low dosages of the tyrosine kinase inhibitor, Imatinib. This drug, also known as Gleevec, has been a FDA-approved and most successful treatment for Philadelphia chromosome-positive chronic myelogenous leukemia (CML) and certain other diseases. More recently, the FDA approved Gleevec for treatingFIP1L1-PDGFRA fusion gene-induced eosinophil leukemia. Commonly, patients suffering this disease respond to low dos (e.g. 100 mg/day) Gleevec but if not attaining complete remission at this dose may require the higher dosages (up to 400/mg/day) typically used to treat CML. Acquired resistance to Gleevec is uncommon but has been observed in patients whose mutated cells develop a T674I or D842V mutation in the fused gene. Should FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases become resistant to or enter an accelorated or blast phase while on Gleevec therapy, the aggressive chemotherapy and/or bone marrow transplantation used to treat aggressive leukemia may be required.
While the success of Gleevec in treating the myeloproliferative neoplasm/myeloblastic leukemia or T-lymphoblastic leukemia/lymphoma forms of FIP1L1-PDGFRA fusion gene-induced disease is unclear, initial treatment with the drug is recommended.
# FIP1L1-RARA
RARA, the Retinoic acid receptor alpha gene, is located on human chromosome 17 at position q21.2 (i.e. 17q21.2), consists of 17 exons, and encodes the nuclear retinoic acid receptor alpha (RARA) protein. The RARA protein, when ligand-bound, regulates the expression of genes that are implicated in the control of development, differentiation, apoptosis, myelopoiesis, and the transcription of transcription factors which in turn regulate the transcription of clock genes. Translocations between this 17q21.2 locus and several other loci have been associated with acute promyelocytic leukemia. Three case reports have found that chromosome translocations between FIP1L1 and RARA gene loci are associated with two cases of acute promyelocytic leukemia and one case of juvenile myelomonocytic leukemia. Relatively little is known about function of or therapy for these translocations except that: a) the fusion gene was generated juxtaposing exons 15 and 3 of FIP1L1 and RARA, respectively; b) retinoic acid, a ligand for the RARA protein, is exceptionally potent in causing a human eosinophil line to die by apoptosis; c) the disease responses to retinoic acid as well as more aggressive therapies could not be evaluated because of severity and rapid progression of the diseases; d) and in vitro studies indicate that the FIP1L1-RARA fusion protein represses the activation of RARA-activated genes. | FIP1L1
Factor interacting with PAPOLA and CPSF1 (i.e, FIP1L1; also termed Pre-mRNA 3'-end-processing factor FIP1) is a protein that in humans is encoded by the FIP1L1 gene (also known as Rhe, FIP1, and hFip1).[1][2] An medically important aspect of the FIP1L1 gene is its fusion with other genes to form fusion genes which cause clonal hypereosinophilia and leukemic diseases in humans.
# Gene
The human FIP1L1 gene is located on chromosome 4 at position q12 (4q12), contains 19 exons, and codes for a complete protein consisting of 594 amino acids. However, alternative splicing of its Precursor mRNA results in multiple transcript variants encoding distinct FIP1L1 protein isoforms. The FIP1L1 gene is found in a wide range of species, being designated as FIP1 in Saccharomyces cerevisiae (yeast) and fip1l1 in coho salmon as well as mice and numerous other mammalian species. [3][4]
In humans, an interstitial chromosomal deletion of about 800 kilobases at 4q12 deletes the CHIC2 gene (i.e.cysteine rich hydrophobic domain 2 gene) to create an in-frame fusion of the FIP1L1 gene with the platelet-derived growth factor receptor alpha gene (PGDFRA) gene. The product of PDGFRA, platelet-derived growth factor receptor alpha (PDGFRA), is a tyrosine kinase receptor of the RTK class III. When bound by its proper ligand, Platelet-derived growth factor (PDGF), it [tyrosine kinase]] becomes active in phosphorylating proteins that, among other functions, promote cell growth and proliferation. (The FIP1L1-PDGFRA mutation was the first description of a gain of function mutation resulting from an interstitial deletion instead of a chromosomal translocation.) The FIP1L1-PDGFRA fusion gene consists of the 5'-end of FIP1L1 united to the 3'-end of PGDFRA at variable breakpoints in both genes extending over a 40 kilobase region in FIP1L1 and a small region of exon 12 in PDGFRA. The fusion gene may produce a protein consisting of the first 233 amino acids of FIP1L1 joined to the last 523 amino acids of PDGFRA or fused proteins consisting of other FIP1L1 and PDGFRA amino acid lengths. The known FIP1L1-PDGFRA fusion proteins exhibit similar if not identical pathological activities.[5]
A Chromosomal translocation of FIP1L1 (4q12) with the Retinoic acid receptor alpha gene, i.e. RARA, (17q12) at various points yields a (15;17)(q22;q21) fusion gene, FIP1L1-RARA that also has been implicated in the development of human leukemic diseases in three case reports.[6]
# FIPL1 function
FIP1L1 is a subunit of the cleavage and polyadenylation specificity factor subunit 1 (CPSF1) complex that polyadenylates the 3' end of precursor mRNAs (pre-mRNA) (see CPSF). The FIP1 motif of 40 amino acids on FIP1L1 is responsible for its binding to CPSF1. CPSF1 is an RNA processing protein that binds to uracil-rich sequences in pre-mRNA, concurrently binds with and stimulates POPOLA, i.e. Polynucleotide adenylyltransferase, and then proceeds to add adenylyl residues to pre-mRNA. This poly-adenylyl action increases pre-mRNA's maturation and movement from the nucleus to cytoplasm while also increasing the stability of the mRNA formed from pre-mRNA: FIP1L1 is a Pre-mRNA 3'-end-processing factor. FIP1L1 gene fusions between it and either the platelet-derived growth factor receptor, alpha (PGDFRA) or Retinoic acid receptor alpha (RARA) genes are causes of certain human diseases associated with pathologically increased levels of blood eosinophils and/or Leukemias.[6][7]
# FIP1L1-PDGFRA fusion genes
## Expression
FIP1L1-PDGFRA fusion genes have been detected in the eosinophils, neutrophils, mast cells, monocytes, T lymphocytes, and B lymphocytes involved in hemtalogical malignancies. This suggests that the initial underlying genetic defect in these malignancies can begin in myeloid or lymphoid progenitor cells or in precursors to these myeloid and lymphoid progenitor cells.[5] In the majority of instances, this fusion appears in and promotes the proliferation and differentiation of myeloid precursor cells along the eosinophil linage. In other cases, however, the fusion, while occurring in myeloid precursor cells, promotes proliferation and differentiation of precursor cells along the neutrophil linage or, less commonly, occurs in lymphoid precursor cells to promote the proliferation and differentiation of precursor cells along the lymphoid lineage.[8]
## Function
FIP1L1-PDGFRA fusion proteins retain PDGFRA-related Tyrosine kinase activity but, unlike PDGFRA, their tyrosine kinase is constitutive, i.e. continuously active: the fusion proteins lack the intact protein's 3'-end that includes its juxtamembrane domain which normally blocks tyrosine kinase activity unless PDGFRA is bound to its activating ligand, platelet-derived growth factor. FIP1L1-PDGFRA fusion proteins are also resistant to PDGFRA's normal pathway of degradation, i.e. Proteasome-dependent ubiquitnation. In consequence, they are highly stable, long-lived, unregulated, and continuously express the stimulating actions of their PDGFRA tyrosine kinase component.[5] In consequence, cells expressing FIP1L1-PDGFRA fusion proteins differentiate and proliferate along eosinophil, other granulocyte, or T lymphocyte lineages and bearers of these mutations suffer either: a) chronic eosinophilia which may progress to hypereosinophilia, the hypereosinophilic syndrome, and chronic eosinophilic leukemia; b) a type of myeloproliferative neoplasm/myeloblastic leukemia not distinguished by eosinophilia; or c) T-lymphoblastic leukemia/lymphoma.[5][8][9] At least one case of FIP1L1-PDGFRA-induced disesae presented as a myeloid sarcoma with eosinophilia has been reported.[5] (i.e. These pathological proliferation and differentiation responses are due to the unabated activity of the fusion proteins' tyrosine kinase in phosphorylating and thereby activating certain proteins that promote these functions. For example, in vitro studies show that a FIP1L1-PDGFRA fusion gene stimulates CD34+ cells to proliferate and differentiate along the eosinophil lineage by causing the activation of NF-κB, STAT5, and Protein kinase B cell signaling pathways. The FIP1L1 component of FIP1L1-PDGFRA is required for the fusion protein to activate STAT4 and protein kinase B.[5][6]
## Clinical aspects
### Incidence
The age-adjusted incidence of hypereosinophilic syndrome/chronic eosinophilic leukemia reported by the International Classification of Diseases for Oncology (Version 3) is ~0.036 per 100,000 with the mean frequency of FIP1L1-PDGFRA gene fusions occurring in ~10% of patients with hypereosinophilia as detected in developed countries. The fused gene occurs with a male/female ratio of 1.47; the reason for this male predominance is not known. The fusion gene has been found in people of all age groups but only rarely in infants and children.[9]
### Presentation
The ~70% of patients with the FIP1L1-PDGFRA fusion gene (also termed the F/P fusion gene) and marked eosinophilia commonly complain of weakness and malaise. They may also present with or have a history of signs and/or symptoms that are due to the damaging actions of tissue-infiltrating eosinophils such as: skin rashes or erythema; eosinophilic myocarditis (i.e. heart disease which may manifest as coronary artery disease, heart failure due to injured cardiac muscle, restrictive cardiomyopathy due to cardiac fibrosis, or blockage of arteries due to the embolization of blood clots that from in the heart); pulmonary airway and parenchymal disease; eosinophilic gastroenteritis; eosinophilic esophagitis; and dysfunction of other organs targeted by eosinophils. The ~30% of patients in whom the fusion gene effects non-eosinophilic granulocyte or lymphoid cell linages present with signs and symptoms respectively of acute myeloid leukemia or lymphoma T-lymphoblastic leukemia/lymphoma or lymphocytic leukemia.[5][10][11]
### Diagnosis
Patients expressing the eosinophil-driving fusion protein typically present with hypereosinophilia arbitrarily define as blood cell counts containing greater than 1.5x109/liter eosinophils that have persisted for more than 6 months. However, lower levels of eosinophil counts and/or eosinophilia with a shorter history of duration are not a counter-indication of the diagnoses. These patients also exhibit elevations in their serum levels of Vitamin B12 and tryptase. Elevations of serum VitaminB12 and tryptase are seen regularly in systemic mastocytosis, a disease which may also present with eosinophilia and must be distinguished from FIP1L1-PDGFRA-induced diseases because of the very different treatments for the two types of diseases. Bone marrow examination may reveal increases in eosinophils and mast cells but usually does not contain elevated numbers of precursor cells or cells with microscopically visible chromosome abnormalities. This examination may be useful in excluding other malignant diseases associated with eosinophilia such as acute myeloid leukemia but does not give definitive results indicating FIP1L1-PDGFRA-induced disease. Rather, definitive results are obtained by detecting the presence of the FIP1L1-PDGFRA fusion gene in the blood and/or bone marrow cells of sufferers by cytogenic analysis using Fluorescence in situ hybridization or nested Reverse transcription polymerase chain reaction testing. Non-eosinophilic forms of FIP1L1-PDGFRA fusion gene-induced diseases are suggested by the presence of morphologically abnormal or excessive numbers of myeloid or lymphoid cells in the blood or bone marrow and, with respect to the lymphoid variants, by the presence of lymphadenopathy and/or lymphoma masses; ultimately, these variants also require demonstration of the FIP1L1-PDGFRA fusion genes fr diagnosis.[5][8][12]
### Treatment
FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases, unlike most other diseases involving hypereosinophilia, are typically resistant to corticosteroid therapy.[13] However, and unlike most cases of myeloid leukemia, FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases (including a case presenting with myeloid sarcoma) have been treated with great success and long term remissions using low dosages of the tyrosine kinase inhibitor, Imatinib.[10] This drug, also known as Gleevec, has been a FDA-approved and most successful treatment for Philadelphia chromosome-positive chronic myelogenous leukemia (CML) and certain other diseases. More recently, the FDA approved Gleevec for treatingFIP1L1-PDGFRA fusion gene-induced eosinophil leukemia. Commonly, patients suffering this disease respond to low dos (e.g. 100 mg/day) Gleevec but if not attaining complete remission at this dose may require the higher dosages (up to 400/mg/day) typically used to treat CML. Acquired resistance to Gleevec is uncommon but has been observed in patients whose mutated cells develop a T674I or D842V mutation in the fused gene.[12][8] Should FIP1L1-PDGFRA fusion gene-induced eosinophil leukemia diseases become resistant to or enter an accelorated or blast phase while on Gleevec therapy, the aggressive chemotherapy and/or bone marrow transplantation used to treat aggressive leukemia may be required.
While the success of Gleevec in treating the myeloproliferative neoplasm/myeloblastic leukemia or T-lymphoblastic leukemia/lymphoma forms of FIP1L1-PDGFRA fusion gene-induced disease is unclear, initial treatment with the drug is recommended.
# FIP1L1-RARA
RARA, the Retinoic acid receptor alpha gene, is located on human chromosome 17 at position q21.2 (i.e. 17q21.2), consists of 17 exons, and encodes the nuclear retinoic acid receptor alpha (RARA) protein. The RARA protein, when ligand-bound, regulates the expression of genes that are implicated in the control of development, differentiation, apoptosis, myelopoiesis, and the transcription of transcription factors which in turn regulate the transcription of clock genes. Translocations between this 17q21.2 locus and several other loci have been associated with acute promyelocytic leukemia.[14] Three case reports have found that chromosome translocations between FIP1L1 and RARA gene loci are associated with two cases of acute promyelocytic leukemia and one case of juvenile myelomonocytic leukemia. Relatively little is known about function of or therapy for these translocations except that: a) the fusion gene was generated juxtaposing exons 15 and 3 of FIP1L1 and RARA, respectively; b) retinoic acid, a ligand for the RARA protein, is exceptionally potent in causing a human eosinophil line to die by apoptosis; c) the disease responses to retinoic acid as well as more aggressive therapies could not be evaluated because of severity and rapid progression of the diseases; d) and in vitro studies indicate that the FIP1L1-RARA fusion protein represses the activation of RARA-activated genes.[6][15] | https://www.wikidoc.org/index.php/FIP1L1 | |
c1ce71645ede3f273b6128204702f5774a15de86 | wikidoc | FITkit | FITkit
FITkit is an immunological test for measuring natural rubber latex (NRL) allergens from a variety of rubber products, such as gloves.
# Description
FITkit is a method for quantification of the major NRL specific allergens: Hev b 1, Hev b 3, Hev b 5 and Hev b 6.02. These tests are based on the enzyme immunometric assay technique and use specific monoclonal antibodies developed against the clinically relevant latex allergens present in NRL products.
FITkit is known also under scientific names EIA (enzymo immunoassay) or IEMA (immuno-enzymometric assay) .
FITkit is a trade mark of Quattromed Ltd. | FITkit
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
FITkit is an immunological test for measuring natural rubber latex (NRL) allergens from a variety of rubber products, such as gloves.
# Description
FITkit is a method for quantification of the major NRL specific allergens: Hev b 1, Hev b 3, Hev b 5 and Hev b 6.02[1]. These tests are based on the enzyme immunometric assay technique and use specific monoclonal antibodies developed against the clinically relevant latex allergens present in NRL products.
FITkit is known also under scientific names EIA (enzymo immunoassay) or IEMA (immuno-enzymometric assay) [2].
FITkit is a trade mark of Quattromed Ltd. | https://www.wikidoc.org/index.php/FITkit | |
6ff31ef3d8a30a8225fae0d02f30cd9e3099c456 | wikidoc | FKBP1B | FKBP1B
Peptidyl-prolyl cis-trans isomerase FKBP1B is an enzyme that in humans is encoded by the FKBP1B gene.
# Function
The protein encoded by this gene is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. This encoded protein is a cis-trans prolyl isomerase that binds the immunosuppressants FK506 (tacrolimus) and rapamycin (sirolimus). It is highly similar to the FK506-binding protein 1A. Its physiological role is thought to be in excitation-contraction coupling in cardiac muscle. There are two alternatively spliced transcript variants of this gene encoding different isoforms.
# Clinical significance
Defective interaction between FKB1B and the ryanodine receptor is thought to be a potential mechanism underlying the arrhythmias seen in those with the genetic condition catecholaminergic polymorphic ventricular tachycardia. | FKBP1B
Peptidyl-prolyl cis-trans isomerase FKBP1B is an enzyme that in humans is encoded by the FKBP1B gene.[1][2]
# Function
The protein encoded by this gene is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. This encoded protein is a cis-trans prolyl isomerase that binds the immunosuppressants FK506 (tacrolimus) and rapamycin (sirolimus). It is highly similar to the FK506-binding protein 1A. Its physiological role is thought to be in excitation-contraction coupling in cardiac muscle. There are two alternatively spliced transcript variants of this gene encoding different isoforms.[2]
# Clinical significance
Defective interaction between FKB1B and the ryanodine receptor is thought to be a potential mechanism underlying the arrhythmias seen in those with the genetic condition catecholaminergic polymorphic ventricular tachycardia. [3] | https://www.wikidoc.org/index.php/FKBP1B | |
f23605ee69036d99b4334919cfeff43799753b22 | wikidoc | FKBP52 | FKBP52
FK506-binding protein 4 is a protein that in humans is encoded by the FKBP4 gene.
# Function
The protein encoded by this gene is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. This encoded protein is a cis-trans prolyl isomerase that binds to the immunosuppressants FK506 and rapamycin. It has high structural and functional similarity to FK506-binding protein 1A (FKBP1A), but unlike FKBP1A, this protein does not have immunosuppressant activity when complexed with FK506. It interacts with interferon regulatory factor-4 and plays an important role in immunoregulatory gene expression in B and T lymphocytes. This encoded protein is known to associate with phytanoyl-CoA alpha-hydroxylase. It can also associate with two heat shock proteins (hsp90 and hsp70) and thus may play a role in the intracellular trafficking of hetero-oligomeric forms of the steroid hormone receptors. This protein correlates strongly with adeno-associated virus type 2 vectors (AAV) resulting in a significant increase in AAV-mediated transgene expression in human cell lines. Thus this encoded protein is thought to have important implications for the optimal use of AAV vectors in human gene therapy.
# Structure
This protein contains TPR repeats and has a PPlase domain.
# Clinical significance
Recent research suggests that FKBP52 may play a role in preventing the Tau protein from turning pathogenic. This may prove significant for the development of new Alzheimer's drugs and for detecting the disease before the onset of clinical symptoms.
# Interactions
FKBP52 has been shown to interact with GLMN. | FKBP52
FK506-binding protein 4 is a protein that in humans is encoded by the FKBP4 gene.[1][2]
# Function
The protein encoded by this gene is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. This encoded protein is a cis-trans prolyl isomerase that binds to the immunosuppressants FK506 and rapamycin. It has high structural and functional similarity to FK506-binding protein 1A (FKBP1A), but unlike FKBP1A, this protein does not have immunosuppressant activity when complexed with FK506. It interacts with interferon regulatory factor-4 and plays an important role in immunoregulatory gene expression in B and T lymphocytes. This encoded protein is known to associate with phytanoyl-CoA alpha-hydroxylase. It can also associate with two heat shock proteins (hsp90 and hsp70) and thus may play a role in the intracellular trafficking of hetero-oligomeric forms of the steroid hormone receptors. This protein correlates strongly with adeno-associated virus type 2 vectors (AAV) resulting in a significant increase in AAV-mediated transgene expression in human cell lines. Thus this encoded protein is thought to have important implications for the optimal use of AAV vectors in human gene therapy.[2]
# Structure
This protein contains TPR repeats and has a PPlase domain.
# Clinical significance
Recent research suggests that FKBP52 may play a role in preventing the Tau protein from turning pathogenic. This may prove significant for the development of new Alzheimer's drugs and for detecting the disease before the onset of clinical symptoms.[3]
# Interactions
FKBP52 has been shown to interact with GLMN.[4][5] | https://www.wikidoc.org/index.php/FKBP52 | |
932e919dd1d97c2e732ce181a33f163ab407f122 | wikidoc | FNBP1L | FNBP1L
Formin-binding protein 1-like is a protein that in humans is encoded by the FNBP1L gene.
# Function
The protein encoded by this gene binds to both CDC42 and N-WASP. This protein promotes CDC42-induced actin polymerization by activating the N-WASP-WIP complex and, therefore, is involved in a pathway that links cell surface signals to the actin cytoskeleton. Alternative splicing results in multiple transcript variants encoding different isoforms.
# Clinical significance
FNBP1L polymorphisms, specifically the SNP rs236330 has been associated with normally varying intelligence differences in adults and in children. | FNBP1L
Formin-binding protein 1-like is a protein that in humans is encoded by the FNBP1L gene.[1][2]
# Function
The protein encoded by this gene binds to both CDC42 and N-WASP. This protein promotes CDC42-induced actin polymerization by activating the N-WASP-WIP complex and, therefore, is involved in a pathway that links cell surface signals to the actin cytoskeleton. Alternative splicing results in multiple transcript variants encoding different isoforms.[2]
# Clinical significance
FNBP1L polymorphisms, specifically the SNP rs236330 has been associated with normally varying intelligence differences in adults[3] and in children.[4] | https://www.wikidoc.org/index.php/FNBP1L | |
c2764f6b67d3d56593bf6c7361d795ff2c691bda | wikidoc | FODMAP | FODMAP
The term FODMAP is an acronym for "Fermentable, Oligo-, Di-, Mono-saccharides And Polyols".
# Overview
FODMAPs are highly fermentable but poorly absorbed short-chain carbohydrates and polyols.
# Medical uses
Low FODMAP diet may help treat irritable bowel syndrome according to a systematic review of randomized controlled trials and a more recent trial. Included in the systematic review was a trial that combined low FODMAPs and high dietary fiber.
A diet that is low in FODMAPs but high in soluble fiber contains psyllium (ispaghula husks). A high fiber, low FODMAP diet has been published and contains 23 grams of fiber and 3 grams of FODMAPs.
Symptoms of gluten sensitivity in the absence of celiac disease may actually be due to fructans in wheat. | FODMAP
The term FODMAP is an acronym for "Fermentable, Oligo-, Di-, Mono-saccharides And Polyols".[1]
# Overview
FODMAPs are highly fermentable but poorly absorbed short-chain carbohydrates and polyols.[1]
# Medical uses
Low FODMAP diet may help treat irritable bowel syndrome according to a systematic review of randomized controlled trials[3] and a more recent trial[4]. Included in the systematic review was a trial that combined low FODMAPs and high dietary fiber.[5]
A diet that is low in FODMAPs but high in soluble fiber contains psyllium (ispaghula husks). A high fiber, low FODMAP diet has been published and contains 23 grams of fiber and 3 grams of FODMAPs. [5]
Symptoms of gluten sensitivity in the absence of celiac disease may actually be due to fructans in wheat.[6] | https://www.wikidoc.org/index.php/FODMAP | |
b3597fed97739afe5e3cc178ad0eb91abed5c439 | wikidoc | FOLFOX | FOLFOX
# Overview
FOLFOX is a chemotherapy regimen for treatment of colorectal cancer, made up of the drugs
- FOL– Folinic acid (leucovorin)
- F – Fluorouracil (5-FU)
- OX – Oxaliplatin (Eloxatin)
# FOLFOX4
Adjuvant treatment in patients with stage III colon cancer is recommended for 12 cycles, every 2 weeks. The recommended dose schedule given every two weeks is as follows:
Day 1: Eloxatin® 85 mg/m² IV infusion in 250-500 mL D5W and leucovorin 200 mg/m² IV infusion in D5W both given over 120 minutes at the same time in separate bags using a Y-line, followed by 5-FU 400 mg/m² IV bolus given over 2-4 minutes, followed by 5-FU 600 mg/m² IV infusion in 500 mL D5W (recommended) as a 22-hour continuous infusion.
Day 2: Leucovorin 200 mg/m² IV infusion over 120 minutes, followed by 5-FU 400 mg/m² IV bolus given over 2-4 minutes, followed by 5-FU 600 mg/m² IV infusion in 500 mL D5W (recommended) as a 22-hour continuous infusion.
Premedication with antiemetics, including 5-HT3 blockers with or without dexamethasone, is recommended. | FOLFOX
# Overview
FOLFOX is a chemotherapy regimen for treatment of colorectal cancer, made up of the drugs
- FOL– Folinic acid (leucovorin)
- F – Fluorouracil (5-FU)
- OX – Oxaliplatin (Eloxatin)[1]
# FOLFOX4
Adjuvant treatment in patients with stage III colon cancer is recommended for 12 cycles, every 2 weeks. The recommended dose schedule given every two weeks is as follows:
Day 1: Eloxatin® 85 mg/m² IV infusion in 250-500 mL D5W and leucovorin 200 mg/m² IV infusion in D5W both given over 120 minutes at the same time in separate bags using a Y-line, followed by 5-FU 400 mg/m² IV bolus given over 2-4 minutes, followed by 5-FU 600 mg/m² IV infusion in 500 mL D5W (recommended) as a 22-hour continuous infusion.
Day 2: Leucovorin 200 mg/m² IV infusion over 120 minutes, followed by 5-FU 400 mg/m² IV bolus given over 2-4 minutes, followed by 5-FU 600 mg/m² IV infusion in 500 mL D5W (recommended) as a 22-hour continuous infusion.
Premedication with antiemetics, including 5-HT3 blockers with or without dexamethasone, is recommended. | https://www.wikidoc.org/index.php/FOLFOX | |
48bea04ca3445ca5da8c1ace0061ea0ac3754248 | wikidoc | FOREST | FOREST
FOREST (an acronym for "Freedom Organisation for the Right to Enjoy Smoking Tobacco") is a United Kingdom political pressure group that campaigns for the right of people to smoke tobacco and opposes attempts to ban or reduce tobacco consumption, as well as casting doubt on medical claims of the health risks of smoking. Describing itself as the "voice and friend of the smoker", it is primarily funded by the tobacco industry.
# History
FOREST was officially founded in 1979 by former Air Chief Marshal Sir Christopher Foxley-Norris.
In 1987 Lord Harris of High Cross, general director of the Institute of Economic Affairs (1957-1989), was appointed chairman, a position he held until his death in October 2006, aged 81. A long-term pipesmoker and an outspoken critic of public smoking bans, Ralph Harris wrote numerous articles and essays on the subject of "passive smoking" (inhaling others' second-hand smoke, also known as "sidestream smoke" or "environmental tobacco smoke"), including "Smoking Out The Truth: a challenge to the Chief Medical Officer" (2005)
in which he declared:
FOREST spokesmen appear regularly on television and radio in the United Kingdom and are frequently quoted by British newspapers.
# Funding
FOREST's website states that it is funded 'mainly' by the tobacco industry.
It has been claimed that FOREST is an astroturf group created by the tobacco industry, and in particular that its establishent was planned by the Tobacco Advisory Committee, the British tobacco industry trade association
According to the document "Minutes of the 11th Meeting of the Public Relations Sub-Committee of TAC Held at Glen House, Stag Place, London, SW1. On Tuesday, 5th August 1979" members of the Public Relations sub-committee of the Tobacco Advisory Committee, the British tobacco industry trade association, were minuted as saying, prior to the creation of FOREST:
# Recent developments
In recent years FOREST has attracted the support of several high profile smokers including artist David Hockney, inventor Trevor Baylis, musician Joe Jackson, restaurateur and TV chef Antony Worrell Thompson, and Claire Fox, director of the Institute of Ideas. In September 2005 Hockney, Jackson and Fox all spoke at a fringe meeting organised by FOREST at the Labour Party conference in Brighton.
In February 2006, FOREST lost its fight against a total ban on smoking in enclosed public places in England from Summer 2007. This includes all pubs, bars, cafés and restaurants, as well as workplaces and private members clubs. Similar bans have come into force in Northern Ireland (Spring 2007) and Wales (April 2007). Scotland introduced its own public smoking ban in March 2006. Despite this, FOREST says it will continue to fight for what it calls "freedom of choice". Current slogans include "Smokers are voters, too", "Enough is enough" and "Nanny state? No thanks". | FOREST
FOREST (an acronym for "Freedom Organisation for the Right to Enjoy Smoking Tobacco") is a United Kingdom political pressure group that campaigns for the right of people to smoke tobacco and opposes attempts to ban or reduce tobacco consumption, as well as casting doubt on medical claims of the health risks of smoking. Describing itself as the "voice and friend of the smoker"[1], it is primarily funded by the tobacco industry.[2]
# History
FOREST was officially founded in 1979 by former Air Chief Marshal Sir Christopher Foxley-Norris.
In 1987 Lord Harris of High Cross, general director of the Institute of Economic Affairs (1957-1989), was appointed chairman, a position he held until his death in October 2006, aged 81. A long-term pipesmoker and an outspoken critic of public smoking bans, Ralph Harris wrote numerous articles and essays on the subject of "passive smoking" (inhaling others' second-hand smoke, also known as "sidestream smoke" or "environmental tobacco smoke"), including "Smoking Out The Truth: a challenge to the Chief Medical Officer" (2005)
[3]
[4]in which he declared:
FOREST spokesmen appear regularly on television and radio in the United Kingdom and are frequently quoted by British newspapers.
# Funding
FOREST's website states that it is funded 'mainly' by the tobacco industry. [2]
It has been claimed that FOREST is an astroturf group created by the tobacco industry, and in particular that its establishent was planned by the Tobacco Advisory Committee, the British tobacco industry trade association
According to the document "Minutes of the 11th Meeting of the Public Relations Sub-Committee of TAC Held at Glen House, Stag Place, London, SW1. On Tuesday, 5th August 1979" members of the Public Relations sub-committee of the Tobacco Advisory Committee, the British tobacco industry trade association, were minuted as saying, prior to the creation of FOREST:
# Recent developments
In recent years FOREST has attracted the support of several high profile smokers including artist David Hockney, inventor Trevor Baylis, musician Joe Jackson, restaurateur and TV chef Antony Worrell Thompson, and Claire Fox, director of the Institute of Ideas. In September 2005 Hockney, Jackson and Fox all spoke at a fringe meeting organised by FOREST at the Labour Party conference in Brighton.
In February 2006, FOREST lost its fight against a total ban on smoking in enclosed public places in England from Summer 2007. This includes all pubs, bars, cafés and restaurants, as well as workplaces and private members clubs. Similar bans have come into force in Northern Ireland (Spring 2007) and Wales (April 2007). Scotland introduced its own public smoking ban in March 2006. Despite this, FOREST says it will continue to fight for what it calls "freedom of choice". Current slogans include "Smokers are voters, too", "Enough is enough" and "Nanny state? No thanks". | https://www.wikidoc.org/index.php/FOREST | |
db459d5adc07eb87d0af9411993c136d8579cf5a | wikidoc | FUNDC1 | FUNDC1
FUN14 domain containing 1 is a protein that in humans is encoded by the FUNDC1 gene.
# Model organisms
Model organisms have been used in the study of FUNDC1 function. A conditional knockout mouse line, called Fundc1tm1a(KOMP)Wtsi was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists — at the Wellcome Trust Sanger Institute.
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.
Twenty two tests were carried out on mutant mice, however no significant abnormalities were observed. | FUNDC1
FUN14 domain containing 1 is a protein that in humans is encoded by the FUNDC1 gene.[1]
# Model organisms
Model organisms have been used in the study of FUNDC1 function. A conditional knockout mouse line, called Fundc1tm1a(KOMP)Wtsi[6][7] was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists — at the Wellcome Trust Sanger Institute.[8][9][10]
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.[4][11]
Twenty two tests were carried out on mutant mice, however no significant abnormalities were observed.[4] | https://www.wikidoc.org/index.php/FUNDC1 | |
40273747d3216218a7f4dcd0ed248a9c11b91a45 | wikidoc | Fam78b | Fam78b
Family with Sequence Similarity 78-Member B (FAM78B) is a protein of unknown function in humans that is encoded by the FAM78B gene (1q24.1). It has orthologous genes and predicted proteins in vertebrates and several invertebrates, but not in arthropods. It has a nuclear localization signal in the protein sequence and a miRNA target region of the mRNA sequence.
# Evolutionary analysis
## Homology
FAM78B has one paralog, FAM78A, and is conserved throughout many species. Orthologs can be found throughout all vertebrates excluding arthropods. FAM78B is also found in several invertebrates including the pacific oyster and liver fluke. FAM78A, it’s paralog, is also found to be conserved in more invertebrates such as the tunicates, worms, and leeches, and make up the distant homologs of FAM78B. The table below contains a list of FAM78B orthologs with percent identity values and time since divergence values relative to the human FAM78B gene or protein.
# Structure
## Gene
The FAM78B gene is located on the sense (negative) strand of chromosome 1 at location 1q24.1 and spans the chromosomal locus 166039271-166135909, covering a total of 96,638 base pairs along the chromosome, the FAM78B gene has 2 exons in its transcript mRNA of 1,481 bp. FAM78B in humans is separated into two exons that have 95,243 bp of introns between them. The gene is highly conserved in vertebrates (excluding arthropods) and the pacific clam and liver fluke.
## mRNA
There is one isoform that has been identified in humans and is composed of two exons that composes a mRNA of 1481 bp.
## Protein
The FAM78B protein has a calculated molecular weight of 30 kDa, has a higher relative abundance of tryptophan (W), has a more greatly conserved c-terminal region, is composed of both alpha helix and beta strand, and resides in the nucleus of the cell after transcription
### General properties
The protein FAM78B consists of 254 amino acids with a predicted molecular weight of 30 kDal. The protein has an isoelectric point of 9.6. FAM78B has a highly conserved C terminus among its orthologs and is histidine poor. The highest conserved amino acids are ISDSDG from aa 104-110, WLVA from aa 171-175, VDP---L--R from aa 199-208, and the C’ terminus, but especially NADQVLMW from aa 240-247.
### Conservation
The amino acid sequence for FAM78B is highly conserved in mammals, having around 86% to 100% sequence similarity. Birds, frogs, mammals, and lizards also have a high degree of similarity to the human FAM78B sequence with similarities between 76% and 83%. Fish have between 56% and 66% sequence similarity. The C terminal end is the most highly conserved across ortholog-containing species from mammals to the pacific sea clam.
# Regulation
## mRNA level
There is one miRNA binding site targeted by miR-24 for sequence CUGAGCCA in Homo sapiens located on the 3' end of the mRNA at 88-95 after the stop codon (bp 167,091,390-167,091,397 on chromosome 1). Stem loop from 155-172 of the 3' end of the mRNA matches with the miRNA site.
## Protein level
Conserved nuclear localization signal (RPKR) from aa 248-252.
# Expression
FAM78B is generally ubiquitously expressed and is highly expressed in regions of the brain.
# Clinical relevance
FAM78B is statistically significantly correlated to chronic kidney disease when there is one of three different single nucleotide polymorphisms (SNPs) including two located in the intron (rs2116519 and rs4074897) and one located in the 5’ UTR (rs987131). | Fam78b
Family with Sequence Similarity 78-Member B (FAM78B) is a protein of unknown function in humans that is encoded by the FAM78B gene (1q24.1). It has orthologous genes and predicted proteins in vertebrates and several invertebrates, but not in arthropods. It has a nuclear localization signal in the protein sequence and a miRNA target region of the mRNA sequence.
# Evolutionary analysis
## Homology
FAM78B has one paralog, FAM78A, and is conserved throughout many species. Orthologs can be found throughout all vertebrates excluding arthropods. FAM78B is also found in several invertebrates including the pacific oyster and liver fluke. FAM78A, it’s paralog, is also found to be conserved in more invertebrates such as the tunicates, worms, and leeches, and make up the distant homologs of FAM78B. The table below contains a list of FAM78B orthologs with percent identity values and time since divergence values relative to the human FAM78B gene or protein.[1]
# Structure
## Gene
The FAM78B gene is located on the sense (negative) strand of chromosome 1 at location 1q24.1 and spans the chromosomal locus 166039271-166135909, covering a total of 96,638 base pairs along the chromosome, the FAM78B gene has 2 exons in its transcript mRNA of 1,481 bp.[2] FAM78B in humans is separated into two exons that have 95,243 bp of introns between them.[3] The gene is highly conserved in vertebrates (excluding arthropods) and the pacific clam and liver fluke.
## mRNA
There is one isoform that has been identified in humans and is composed of two exons that composes a mRNA of 1481 bp.[4]
## Protein
The FAM78B protein has a calculated molecular weight of 30 kDa, has a higher relative abundance of tryptophan (W), has a more greatly conserved c-terminal region, is composed of both alpha helix and beta strand, and resides in the nucleus of the cell after transcription [5]
### General properties
The protein FAM78B consists of 254 amino acids with a predicted molecular weight of 30 kDal. The protein has an isoelectric point of 9.6. FAM78B has a highly conserved C terminus among its orthologs and is histidine poor.[6] The highest conserved amino acids are ISDSDG from aa 104-110, WLVA from aa 171-175, VDP---L--R from aa 199-208, and the C’ terminus, but especially NADQVLMW from aa 240-247.
### Conservation
The amino acid sequence for FAM78B is highly conserved in mammals, having around 86% to 100% sequence similarity. Birds, frogs, mammals, and lizards also have a high degree of similarity to the human FAM78B sequence with similarities between 76% and 83%. Fish have between 56% and 66% sequence similarity. The C terminal end is the most highly conserved across ortholog-containing species from mammals to the pacific sea clam. [4]
# Regulation
## mRNA level
There is one miRNA binding site targeted by miR-24 for sequence CUGAGCCA in Homo sapiens located on the 3' end of the mRNA at 88-95 after the stop codon (bp 167,091,390-167,091,397 on chromosome 1). Stem loop from 155-172 of the 3' end of the mRNA matches with the miRNA site.[7]
## Protein level
Conserved nuclear localization signal (RPKR) from aa 248-252.
# Expression
FAM78B is generally ubiquitously expressed [8] and is highly expressed in regions of the brain.[9]
# Clinical relevance
FAM78B is statistically significantly correlated to chronic kidney disease when there is one of three different single nucleotide polymorphisms (SNPs) including two located in the intron (rs2116519 and rs4074897) and one located in the 5’ UTR (rs987131). | https://www.wikidoc.org/index.php/Fam78b | |
a76d7a31b688b60a0689f0443b7520b2d0baa472 | wikidoc | Family | Family
Family denotes a group of people affiliated by consanguinity, affinity, and co-residence. Although the concept of consanguinity originally referred to relations by "blood," many anthropologists have argued that one must understand the notion of "blood" metaphorically, and that many societies understand 'family' through other concepts rather than through genetic distance.
Many sociologists and anthropologists believe the primary function of the family is to reproduce society, either biologically, socially, or both. Thus, one's experience of one's family shifts over time. From the perspective of children, the family is a family of orientation: the family serves to locate children socially, and plays a major role in their enculturation and socialization. From the point of view of the parent(s), the family is a family of procreation the goal of which is to produce and enculturate and socialize children. However, producing children is not the only function of the family; in societies with a sexual division of labor, marriage, and the resulting relationship between two people, is necessary for the formation of an economically productive household.
A conjugal family consists of one or more mothers and their children, and/or one or more spouses, usually husbands. The most common form of this family in the western world is regularly referred to as a nuclear family.
A consanguineal family consists of a mother and her children, and other people — usually the family of the mother, like her husband. This kind of family is common where mothers do not have the resources to rear their children on their own, and especially where property is inherited. When important property is owned by men, consanguineal families commonly consist of a husband and wife, their children and other members of the husband's family.
A matrifocal family consists of a mother and her children. Generally, these children are her biological offspring, although adoption of children is a practice in nearly every society. This kind of family is common where women have the resources to rear their children by themselves, or where men are more mobile than women.
# Economic functions
Anthropologists have often supposed that the family in a traditional society forms the primary economic unit. This economic role has gradually diminished in modern times, and in societies like the United States it has become much smaller — except in certain sectors such as agriculture and in a few upper class families. In China the family as an economic unit still plays a strong role in the countryside. However, the relations between the economic role of the family, its socio-economic mode of production and cultural values remain highly complex.
# Political functions
On the other hand family structures or its internal relationships may affect both state and religious institutions. J.F. del Giorgio in The Oldest Europeans points that the high status of women among the descendants of the post-glacial Paleolithic European population was coherent with the fierce love of freedom of pre-Indo-European tribes. He believes that the extraordinary respect for women in those families made that children raised in such atmosphere tended to distrust strong, authoritarian leaders. According to del Giorgio, European democracies have their roots in those ancient ancestors.
# Kinship terminology
Anthropologist Lewis Henry Morgan (1818–1881) performed the first survey of kinship terminologies in use around the world. Though much of his work is now considered dated, he argued that kinship terminologies reflect different sets of distinctions. For example, most kinship terminologies distinguish between sexes (the difference between a brother and a sister) and between generations (the difference between a child and a parent). Moreover, he argued, kinship terminologies distinguish between relatives by blood and marriage (although recently some anthropologists have argued that many societies define kinship in terms other than "blood").
Morgan made a distinction between kinship systems that use classificatory terminology and those that use descriptive terminology. Morgan's distinction is widely misunderstood, even by contemporary anthropologists. Classificatory systems are generally and erroneously understood to be those that "class together" with a single term relatives who actually do not have the same type of relationship to ego. (What defines "same type of relationship" under such definitions seems to be genealogical relationship. This is more than a bit problematic given that any genealogical description, no matter how standardized, employs words originating in a folk understanding of kinship.) What Morgan's terminology actually differentiates are those (classificatory) kinship systems that do not distinguish lineal and collateral relationships and those (descriptive) kinship systems which do. Morgan, a lawyer, came to make this distinction in an effort to understand Seneca inheritance practices. A Seneca man's effects were inherited by his sisters' children rather than by his own children.
Morgan identified six basic patterns of kinship terminologies:
- Hawaiian: only distinguishes relatives based upon sex and generation.
- Sudanese: no two relatives share the same term.
- Eskimo: in addition to distinguishing relatives based upon sex and generation, also distinguishes between lineal relatives and collateral relatives.
- Iroquois: in addition to sex and generation, also distinguishes between siblings of opposite sexes in the parental generation.
- Crow: a matrilineal system with some features of an Iroquois system, but with a "skewing" feature in which generation is "frozen" for some relatives.
- Omaha: like a Crow system but patrilineal.
## Western kinship
Most Western societies employ Eskimo kinship terminology. This kinship terminology commonly occurs in societies based on conjugal (or nuclear) families, where nuclear families have a degree of relatively mobility.
Members of the nuclear family (or immediate family) use descriptive kinship terms:
- Mother: a female parent
- Father: a male parent
- Son: a male child of the parent(s)
- Daughter: a female child of the parent(s)
- Brother: a male child of the same parent(s)
- Sister: a female child of the same parent(s)
- Grandfather: father of a father or mother
- Grandmother: mother of a father or mother
Such systems generally assume that the mother's husband has also served as the biological father. In some families, a woman may have children with more than one man or a man may have children with more than one woman. The system refers to a child who shares only one parent with another child as a "half-brother" or "half-sister". For children who do not share biological or adoptive parents in common, English-speakers use the term "stepbrother" or "stepsister" to refer to their new relationship with each other when one of their biological parents marries one of the other child's biological parents.
Any person (other than the biological parent of a child) who marries the parent of that child becomes the "stepparent" of the child, either the "stepmother" or "stepfather". The same terms generally apply to children adopted into a family as to children born into the family.
Typically, societies with conjugal families also favor neolocal residence; thus upon marriage a person separates from the nuclear family of their childhood (family of orientation) and forms a new nuclear family (family of procreation). This practice means that members of one's own nuclear family once functioned as members of another nuclear family, or may one day become members of another nuclear family.
Members of the nuclear families of members of one's own (former) nuclear family may class as lineal or as collateral. Kin who regard them as lineal refer to them in terms that build on the terms used within the nuclear family:
- Grandparent
Grandfather: a parent's father
Grandmother: a parent's mother
- Grandfather: a parent's father
- Grandmother: a parent's mother
- Grandson: a child's son
- Granddaughter: a child's daughter
For collateral relatives, more classificatory terms come into play, terms that do not build on the terms used within the nuclear family:
- Uncle: father's brother, mother's brother, father's/mother's sister's husband
- Aunt: father's sister, mother's sister, father's/mother's brother's wife
- Nephew: sister's son, brother's son, wife's brother's son, wife's sister's son, husband's brother's son, husband's sister's son
- Niece: sister's daughter, brother's daughter, wife's brother's daughter, wife's sister's daughter, husband's brother's daughter, husband's sister's daughter
When additional generations intervene (in other words, when one's collateral relatives belong to the same generation as one's grandparents or grandchildren), the prefix "grand" modifies these terms. (Although in casual usage in the USA a "grand aunt" is often referred to as a "great aunt", for instance.) And as with grandparents and grandchildren, as more generations intervene the prefix becomes "great grand", adding an additional "great" for each additional generation.
Most collateral relatives have never had membership of the nuclear family of the members of one's own nuclear family.
- Cousin: the most classificatory term; the children of aunts or uncles. One can further distinguish cousins by degrees of collaterality and by generation. Two persons of the same generation who share a grandparent count as "first cousins" (one degree of collaterality); if they share a great-grandparent they count as "second cousins" (two degrees of collaterality) and so on. If two persons share an ancestor, one as a grandchild and the other as a great-grandchild of that individual, then the two descendants class as "first cousins once removed" (removed by one generation); if the shared ancestor figures as the grandparent of one individual and the great-great-grandparent of the other, the individuals class as "first cousins twice removed" (removed by two generations), and so on. Similarly, if the shared ancestor figures as the great-grandparent of one person and the great-great-grandparent of the other, the individuals class as "second cousins once removed". Hence the phrase "third cousin once removed upwards".
Distant cousins of an older generation (in other words, one's parents' first cousins), though technically first cousins once removed, often get classified with "aunts" and "uncles".
Similarly, a person may refer to close friends of one's parents as "aunt" or "uncle", or may refer to close friends as "brother" or "sister", using the practice of fictive kinship.
English-speakers mark relationships by marriage (except for wife/husband) with the tag "-in-law". The mother and father of one's spouse become one's mother-in-law and father-in-law; the female spouse of one's child becomes one's daughter-in-law and the male spouse of one's child becomes one's son-in-law. The term "Sister-in-law" refers to three essentially different relationships, either the wife of one's sibling, or the sister of one's spouse, or the wife of one's spouse's sibling. "Brother-in-law" expresses a similar ambiguity. No special terms exist for the rest of one's spouse's family.
The terms "half-brother" and "half-sister" indicate siblings who share only one biological or adoptive parent.
# Family in the West
The different types of families occur in a wide variety of settings, and their specific functions and meanings depend largely on their relationship to other social institutions. Sociologists have a special interest in the function and status of these forms in stratified (especially capitalist) societies.
The term "nuclear family" is commonly used, especially in the United States and Europe, to refer to conjugal families. Sociologists distinguish between conjugal families (relatively independent of the kindreds of the parents and of other families in general) and nuclear families (which maintain relatively close ties with their kindreds).
The term "extended family" is also common, especially in the United States and Europe. This term has two distinct meanings. First, it serves as a synonym of "consanguinal family". Second, in societies dominated by the conjugal family, it refers to kindred (an egocentric network of relatives that extends beyond the domestic group) who do not belong to the conjugal family.
These types refer to ideal or normative structures found in particular societies. Any society will exhibit some variation in the actual composition and conception of families. Much sociological, historical and anthropological research dedicates itself to the understanding of this variation, and of changes in the family form over time. Thus, some speak of the bourgeois family, a family structure arising out of 16th-century and 17th-century European households, in which the family centers on a marriage between a man and woman, with strictly-defined gender-roles. The man typically has responsibility for income and support, the woman for home and family matters.
Philosophers and psychiatrists like Deleuze, Guattari, Laing, Reich, explained that the patriarchal-family conceived in the West tradition (husband-wife-children isolated from the outside) serves the purpose of perpetuating a propertarian and authoritarian society. The child grows according to the Oedipal model typical of capitalist societies and he becomes in turn owner of submissive children and protector of the woman.
According to the analysis of Michel Foucault, in the west:
the family organization, precisely to the extent that it was insular and heteromorphous with respect to the other power mechanisms, was used to support the great "maneuvers" employed for the Malthusian control of the birthrate, for the populationist incitements, for the medicalization of sex and the psychiatrization of its nongenital forms.
According to the work of scholars Max Weber, Alan Macfarlane, Steven Ozment, Jack Goody and Peter Laslett, the huge transformation that led to modern marriage in Western democracies was "fueled by the religio-cultural value system provided by elements of Judaism, early Christianity, Roman Catholic canon law and the Protestant Reformation".
In contemporary Europe and the United States, people in academic, political and civil sectors have called attention to single-father-headed households, and families headed by same-sex couples, although academics point out that these forms exist in other societies. Also the term blended family or stepfamily describes families with mixed parents: one or both parents remarried, bringing children of the former family into the new family.
## Contemporary views of the family
Contemporary society generally views family as a haven from the world, supplying absolute fulfillment. The family is considered to encourage "intimacy, love and trust where individuals may escape the competition of dehumanizing forces in modern society from the rough and tumble industrialized world, and as a place where warmth, tenderness and understanding can be expected from a loving mother, and protection from the world can be expected from the father. However, the idea of protection is declining as civil society faces less internal conflict combined with increased civil rights and protection from the state. To many, the ideal of personal or family fulfillment has replaced protection as the major role of the family. The family now supplies what is “vitally needed but missing from other social arrangements”.
Social conservatives often express concern over a purported decay of the family and see this as a sign of the crumbling of contemporary society. They feel that the family structures of the past were superior to those today and believe that families were more stable and happier at a time when they did not have to contend with problems such as illegitimate children and divorce. Others dispute this theory, claiming “there is no golden age of the family gleaming at us in the far back historical past”.
A study performed by scientists from Iceland found that mating with a relative can significantly increase the number of children in a family. A lot of societies consider inbreeding unacceptable. Scientists warn that inbreeding may rise the chances of a child getting two copies of disease-causing recessive genes and in such a way it may lead to genetic disorders and higher infant mortality.
Scientists found that couples formed of relatives had more children and grandchildren than unrelated couples. The study revealed that when a husband and wife were third cousins, they had an average of 4.0 children and 9.2 grandchildren. If a woman was in relationship with her eight cousin, then the number of children declined, showing an average of 3,3 children and 7,3 grandchildren .
# Size
Natalism is the belief that human reproduction is the basis for individual existence, and therefore promotes having large families.
Many religions, e.g., Judaism, encourage their followers to procreate and have many children.
In recent times, there has been an increasing amount of family planning and a following decrease in total fertility rate in many parts of the world, in part due to concerns of overpopulation.
Many countries with population decline offer incentives for people to have large families as a means of national efforts to reverse declining populations. | Family
Family denotes a group of people affiliated by consanguinity, affinity, and co-residence. Although the concept of consanguinity originally referred to relations by "blood," many anthropologists have argued that one must understand the notion of "blood" metaphorically, and that many societies understand 'family' through other concepts rather than through genetic distance.
Many sociologists and anthropologists believe the primary function of the family is to reproduce society, either biologically, socially, or both. Thus, one's experience of one's family shifts over time. From the perspective of children, the family is a family of orientation: the family serves to locate children socially, and plays a major role in their enculturation and socialization. From the point of view of the parent(s), the family is a family of procreation the goal of which is to produce and enculturate and socialize children.[1] However, producing children is not the only function of the family; in societies with a sexual division of labor, marriage, and the resulting relationship between two people, is necessary for the formation of an economically productive household.
A conjugal family consists of one or more mothers and their children, and/or one or more spouses, usually husbands. The most common form of this family in the western world is regularly referred to as a nuclear family.
A consanguineal family consists of a mother and her children, and other people — usually the family of the mother, like her husband. This kind of family is common where mothers do not have the resources to rear their children on their own, and especially where property is inherited. When important property is owned by men, consanguineal families commonly consist of a husband and wife, their children and other members of the husband's family.
A matrifocal family consists of a mother and her children. Generally, these children are her biological offspring, although adoption of children is a practice in nearly every society. This kind of family is common where women have the resources to rear their children by themselves, or where men are more mobile than women.
# Economic functions
Anthropologists have often supposed that the family in a traditional society forms the primary economic unit. This economic role has gradually diminished in modern times, and in societies like the United States it has become much smaller — except in certain sectors such as agriculture and in a few upper class families. In China the family as an economic unit still plays a strong role in the countryside. However, the relations between the economic role of the family, its socio-economic mode of production and cultural values remain highly complex.
# Political functions
On the other hand family structures or its internal relationships may affect both state and religious institutions. J.F. del Giorgio in The Oldest Europeans points that the high status of women among the descendants of the post-glacial Paleolithic European population was coherent with the fierce love of freedom of pre-Indo-European tribes. He believes that the extraordinary respect for women in those families made that children raised in such atmosphere tended to distrust strong, authoritarian leaders. According to del Giorgio, European democracies have their roots in those ancient ancestors.
# Kinship terminology
Anthropologist Lewis Henry Morgan (1818–1881) performed the first survey of kinship terminologies in use around the world. Though much of his work is now considered dated, he argued that kinship terminologies reflect different sets of distinctions. For example, most kinship terminologies distinguish between sexes (the difference between a brother and a sister) and between generations (the difference between a child and a parent). Moreover, he argued, kinship terminologies distinguish between relatives by blood and marriage (although recently some anthropologists have argued that many societies define kinship in terms other than "blood").
Morgan made a distinction between kinship systems that use classificatory terminology and those that use descriptive terminology. Morgan's distinction is widely misunderstood, even by contemporary anthropologists. Classificatory systems are generally and erroneously understood to be those that "class together" with a single term relatives who actually do not have the same type of relationship to ego. (What defines "same type of relationship" under such definitions seems to be genealogical relationship. This is more than a bit problematic given that any genealogical description, no matter how standardized, employs words originating in a folk understanding of kinship.) What Morgan's terminology actually differentiates are those (classificatory) kinship systems that do not distinguish lineal and collateral relationships and those (descriptive) kinship systems which do. Morgan, a lawyer, came to make this distinction in an effort to understand Seneca inheritance practices. A Seneca man's effects were inherited by his sisters' children rather than by his own children.[2]
Morgan identified six basic patterns of kinship terminologies:
- Hawaiian: only distinguishes relatives based upon sex and generation.
- Sudanese: no two relatives share the same term.
- Eskimo: in addition to distinguishing relatives based upon sex and generation, also distinguishes between lineal relatives and collateral relatives.
- Iroquois: in addition to sex and generation, also distinguishes between siblings of opposite sexes in the parental generation.
- Crow: a matrilineal system with some features of an Iroquois system, but with a "skewing" feature in which generation is "frozen" for some relatives.
- Omaha: like a Crow system but patrilineal.
## Western kinship
Template:Seealso
Most Western societies employ Eskimo kinship terminology. This kinship terminology commonly occurs in societies based on conjugal (or nuclear) families, where nuclear families have a degree of relatively mobility.
Members of the nuclear family (or immediate family) use descriptive kinship terms:
- Mother: a female parent
- Father: a male parent
- Son: a male child of the parent(s)
- Daughter: a female child of the parent(s)
- Brother: a male child of the same parent(s)
- Sister: a female child of the same parent(s)
- Grandfather: father of a father or mother
- Grandmother: mother of a father or mother
Such systems generally assume that the mother's husband has also served as the biological father. In some families, a woman may have children with more than one man or a man may have children with more than one woman. The system refers to a child who shares only one parent with another child as a "half-brother" or "half-sister". For children who do not share biological or adoptive parents in common, English-speakers use the term "stepbrother" or "stepsister" to refer to their new relationship with each other when one of their biological parents marries one of the other child's biological parents.
Any person (other than the biological parent of a child) who marries the parent of that child becomes the "stepparent" of the child, either the "stepmother" or "stepfather". The same terms generally apply to children adopted into a family as to children born into the family.
Typically, societies with conjugal families also favor neolocal residence; thus upon marriage a person separates from the nuclear family of their childhood (family of orientation) and forms a new nuclear family (family of procreation). This practice means that members of one's own nuclear family once functioned as members of another nuclear family, or may one day become members of another nuclear family.
Members of the nuclear families of members of one's own (former) nuclear family may class as lineal or as collateral. Kin who regard them as lineal refer to them in terms that build on the terms used within the nuclear family:
- Grandparent
Grandfather: a parent's father
Grandmother: a parent's mother
- Grandfather: a parent's father
- Grandmother: a parent's mother
- Grandson: a child's son
- Granddaughter: a child's daughter
For collateral relatives, more classificatory terms come into play, terms that do not build on the terms used within the nuclear family:
- Uncle: father's brother, mother's brother, father's/mother's sister's husband
- Aunt: father's sister, mother's sister, father's/mother's brother's wife
- Nephew: sister's son, brother's son, wife's brother's son, wife's sister's son, husband's brother's son, husband's sister's son
- Niece: sister's daughter, brother's daughter, wife's brother's daughter, wife's sister's daughter, husband's brother's daughter, husband's sister's daughter
When additional generations intervene (in other words, when one's collateral relatives belong to the same generation as one's grandparents or grandchildren), the prefix "grand" modifies these terms. (Although in casual usage in the USA a "grand aunt" is often referred to as a "great aunt", for instance.) And as with grandparents and grandchildren, as more generations intervene the prefix becomes "great grand", adding an additional "great" for each additional generation.
Most collateral relatives have never had membership of the nuclear family of the members of one's own nuclear family.
- Cousin: the most classificatory term; the children of aunts or uncles. One can further distinguish cousins by degrees of collaterality and by generation. Two persons of the same generation who share a grandparent count as "first cousins" (one degree of collaterality); if they share a great-grandparent they count as "second cousins" (two degrees of collaterality) and so on. If two persons share an ancestor, one as a grandchild and the other as a great-grandchild of that individual, then the two descendants class as "first cousins once removed" (removed by one generation); if the shared ancestor figures as the grandparent of one individual and the great-great-grandparent of the other, the individuals class as "first cousins twice removed" (removed by two generations), and so on. Similarly, if the shared ancestor figures as the great-grandparent of one person and the great-great-grandparent of the other, the individuals class as "second cousins once removed". Hence the phrase "third cousin once removed upwards".
Distant cousins of an older generation (in other words, one's parents' first cousins), though technically first cousins once removed, often get classified with "aunts" and "uncles".
Similarly, a person may refer to close friends of one's parents as "aunt" or "uncle", or may refer to close friends as "brother" or "sister", using the practice of fictive kinship.
English-speakers mark relationships by marriage (except for wife/husband) with the tag "-in-law". The mother and father of one's spouse become one's mother-in-law and father-in-law; the female spouse of one's child becomes one's daughter-in-law and the male spouse of one's child becomes one's son-in-law. The term "Sister-in-law" refers to three essentially different relationships, either the wife of one's sibling, or the sister of one's spouse, or the wife of one's spouse's sibling. "Brother-in-law" expresses a similar ambiguity. No special terms exist for the rest of one's spouse's family.
The terms "half-brother" and "half-sister" indicate siblings who share only one biological or adoptive parent.
# Family in the West
The different types of families occur in a wide variety of settings, and their specific functions and meanings depend largely on their relationship to other social institutions. Sociologists have a special interest in the function and status of these forms in stratified (especially capitalist) societies.
The term "nuclear family" is commonly used, especially in the United States and Europe, to refer to conjugal families. Sociologists distinguish between conjugal families (relatively independent of the kindreds of the parents and of other families in general) and nuclear families (which maintain relatively close ties with their kindreds).
The term "extended family" is also common, especially in the United States and Europe. This term has two distinct meanings. First, it serves as a synonym of "consanguinal family". Second, in societies dominated by the conjugal family, it refers to kindred (an egocentric network of relatives that extends beyond the domestic group) who do not belong to the conjugal family.
These types refer to ideal or normative structures found in particular societies. Any society will exhibit some variation in the actual composition and conception of families. Much sociological, historical and anthropological research dedicates itself to the understanding of this variation, and of changes in the family form over time. Thus, some speak of the bourgeois family, a family structure arising out of 16th-century and 17th-century European households, in which the family centers on a marriage between a man and woman, with strictly-defined gender-roles. The man typically has responsibility for income and support, the woman for home and family matters.
Philosophers and psychiatrists like Deleuze, Guattari, Laing, Reich, explained that the patriarchal-family conceived in the West tradition (husband-wife-children isolated from the outside) serves the purpose of perpetuating a propertarian and authoritarian society. The child grows according to the Oedipal model typical of capitalist societies and he becomes in turn owner of submissive children and protector of the woman.[4][5][6][7][8][9]
According to the analysis of Michel Foucault, in the west:
the [conjugal] family organization, precisely to the extent that it was insular and heteromorphous with respect to the other power mechanisms, was used to support the great "maneuvers" employed for the Malthusian control of the birthrate, for the populationist incitements, for the medicalization of sex and the psychiatrization of its nongenital forms.
According to the work of scholars Max Weber, Alan Macfarlane, Steven Ozment, Jack Goody and Peter Laslett, the huge transformation that led to modern marriage in Western democracies was "fueled by the religio-cultural value system provided by elements of Judaism, early Christianity, Roman Catholic canon law and the Protestant Reformation".[10]
In contemporary Europe and the United States, people in academic, political and civil sectors have called attention to single-father-headed households, and families headed by same-sex couples,[citation needed] although academics point out that these forms exist in other societies. Also the term blended family or stepfamily describes families with mixed parents: one or both parents remarried, bringing children of the former family into the new family.[11]
## Contemporary views of the family
Contemporary society generally views family as a haven from the world, supplying absolute fulfillment. The family is considered to encourage "intimacy, love and trust where individuals may escape the competition of dehumanizing forces in modern society from the rough and tumble industrialized world, and as a place where warmth, tenderness and understanding can be expected from a loving mother, and protection from the world can be expected from the father. However, the idea of protection is declining as civil society faces less internal conflict combined with increased civil rights and protection from the state. To many, the ideal of personal or family fulfillment has replaced protection as the major role of the family. The family now supplies what is “vitally needed but missing from other social arrangements”.[12]
Social conservatives often express concern over a purported decay of the family and see this as a sign of the crumbling of contemporary society. They feel that the family structures of the past were superior to those today and believe that families were more stable and happier at a time when they did not have to contend with problems such as illegitimate children and divorce. Others dispute this theory, claiming “there is no golden age of the family gleaming at us in the far back historical past”.[13]
A study performed by scientists from Iceland found that mating with a relative can significantly increase the number of children in a family. A lot of societies consider inbreeding unacceptable. Scientists warn that inbreeding may rise the chances of a child getting two copies of disease-causing recessive genes and in such a way it may lead to genetic disorders and higher infant mortality.
Scientists found that couples formed of relatives had more children and grandchildren than unrelated couples. The study revealed that when a husband and wife were third cousins, they had an average of 4.0 children and 9.2 grandchildren. If a woman was in relationship with her eight cousin, then the number of children declined, showing an average of 3,3 children and 7,3 grandchildren . [14]
# Size
Natalism is the belief that human reproduction is the basis for individual existence, and therefore promotes having large families.
Many religions, e.g., Judaism[15], encourage their followers to procreate and have many children.
In recent times, there has been an increasing amount of family planning and a following decrease in total fertility rate in many parts of the world, in part due to concerns of overpopulation.
Many countries with population decline offer incentives for people to have large families as a means of national efforts to reverse declining populations. | https://www.wikidoc.org/index.php/Familial | |
4ed35e24160191ed1adacfec01ed5f459c7f527a | wikidoc | Famine | Famine
# Overview
A famine is a widespread shortage of food that may apply to any faunal species, which phenomenon is usually accompanied by regional malnutrition, starvation, epidemic, and increased mortality.
Although most famines coincide with regional shortages of food, famine in some human populations has occurred amid plenty or on account of acts of economic or military policy that have deprived certain populations of sufficient food to ensure survival. Historically, famines have occurred because of drought, crop failure, pestilence, and man-made causes such as war or misguided economic policies. Bad harvests, overpopulation, and epidemic diseases like the Black Death helped cause hundreds of famines in Europe during the Middle Ages, including 95 in the British Isles and 75 in France.
During the 20th century, an estimated 70 million people died from famines across the world, of whom an estimated 30 million died during the famine of 1958–61 in China. The other most notable famines of the century included the 1942–1945 disaster in Bengal, famines in China in 1928 and 1942, and a sequence of man-made famines in the Soviet Union, including the Holodomor, Stalin's famine inflicted on Ukraine in 1932–33. A few of the great famines of the late 20th century were: the Biafran famine in the 1960s, the disaster in Cambodia in the 1970s, the Ethiopian famine of 1983–85 and the North Korean famine of the 1990s.
Famine can be induced by a human population beyond the regional carrying capacity to provide food resources. An alternate view of famine is a failure of the poor to command sufficient resources to acquire essential food (the "entitlement theory" of Amartya Sen), analyses of famine that focused on the political-economic processes driving the creation of famine, an understanding of the complex reasons for mortality in famines, an appreciation of the extent to which famine-vulnerable communities have well-developed strategies for coping with the threat of famine, and the role of warfare and terrorism in creating famine. Modern relief agencies categorize various gradations of famine according to a famine scale.
Many areas that suffered famines in the past have protected themselves through technological and social development. The first area in Europe to eliminate famine was the Netherlands, which saw its last peacetime famines in the early 17th century as it became a major economic power and established a complex political organization. Noting that many famines occur under dictatorship, colonial rule, or during war, Amartya Sen has posited that no functioning democracy has suffered a famine in modern times.
# Characteristics of famine
Today, famine strikes Sub-Saharan African countries the hardest, but with exhaustion of food resources, overdrafting of groundwater, wars, internal struggles, and economic failure, famine continues to be a worldwide problem with millions of individuals suffering. These famines cause widespread malnutrition and impoverishment; The famine in Ethiopia in the 1980s had an immense death toll, although Asian famines of the 20th century have also produced extensive death tolls. Modern African famines are characterised by widespread destitution and malnutrition, with heightened mortality confined to young children. Relief technologies including immunization, improved public health infrastructure, general food rations and supplementary feeding for vulnerable children, has blunted the mortality impacts of famines, while leaving their economic causes and consequences unchanged. Humanitarian crises also arise from civil wars, refugee flows and episodes of extreme violence and state collapse, creating famine conditions among the affected populations.
Despite repeated stated intentions by the world's leaders to end hunger and famine, famine remains a chronic threat in much of Africa and Asia. In July 2005, the Famine Early Warning Systems Network labelled Niger with emergency status, as well as Chad, Ethiopia, South Sudan, Somalia and Zimbabwe. In January 2006, the United Nations Food and Agriculture Organization warned that 11 million people in Somalia, Kenya, Djibouti and Ethiopia were in danger of starvation due to the combination of severe drought and military conflicts. In 2006, the most serious humanitarian crisis in Africa is in Sudan's region Darfur.
Some believe that the Green Revolution was an answer to famine in the 1970s and 1980s. The Green Revolution began in the 20th century with hybrid strains of high-yielding crops. Between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%. Some criticize the process, stating that these new high-yielding crops require more chemical fertilizers and pesticides, which can harm the environment. However, it was an option for developing nations suffering from famine. These high-yielding crops make it technically possible to feed much of the world population. They can be developed to provide enhanced nutrition, and a well-nourished, well-developed population would emerge. Some say that the problems of famine and ill-nourishment are the results of ethical dilemmas over using the technologies we have, as well as cultural and class differences. Furthermore, there are indications that regional food production has peaked in many world sectors, due to certain strategies associated with intensive agriculture such as groundwater overdrafting and overuse of pesticides and other agricultural chemicals.
Frances Moore Lappé, later co-founder of the Institute for Food and Development Policy (Food First) argued in Diet for a Small Planet (1971) that vegetarian diets can provide food for larger populations, with the same resources, compared to omnivorous diets.
Noting that modern famines are sometimes the outcome of misguided economic policies, political design to impoverish or marginalize certain populations, or acts of war, political economists have investigated the political conditions under which famine is prevented. Amartya Sen states that the liberal institutions that exist in India, including competitive elections and a free press, have played a major role in preventing famine in that country since independence. Alex de Waal has developed this theory to focus on the "political contract" between rulers and people that ensures famine prevention, noting the rarity of such political contracts in Africa, and the danger that international relief agencies will undermine such contracts through removing the locus of accountability for famines from national governments.
## Causes of famine
The cause of famine is a combination of political, economic, and biological factors. Because of food aid, improved storage and preservation food processing- it is a popular misconception that the only cause of famine is insufficient food supply, or in biological terms, a population beyond its regional carrying capacity. Famines can be exacerbated by poor governance or inadequate logistics for food distribution. In most modern cases, it is political strife, poverty, and violence that disrupts the agricultural and food distribution processes. Modern famines have often occurred in nations that, as a whole, were not initially suffering a shortage of food. One of the largest historical famines (proportional to the affected population) was the Great Irish Famine, 1845-1849, which began in 1845 and occurred as food was being shipped from Ireland to England because the English could afford to pay higher prices. The largest famine ever (in absolute terms) was the Chinese famine of 1958–61 that occurred as a result of the Great Leap Forward. In a similar manner, the 1973 famine in Ethiopia was concentrated in the Wollo region, although food was being shipped out of Wollo to the capital city of Addis Ababa where it could command higher prices. In contrast, at the same time that the citizens of the dictatorships of Ethiopia and Sudan had massive famines in the late-1970s and early-1980s, the democracies of Botswana and Zimbabwe avoided them, despite having worse drops in national food production. This was possible through the simple step of creating short-term employment for the worst-affected groups, thus ensuring a minimal amount of income to buy food, for the duration of the localized food disruption and was taken under criticism from opposition political parties and intense media coverage.
The failure of a harvest or the change in conditions, such as drought, can create a situation whereby large numbers of people live where the carrying capacity of the land has dropped radically. Famine is then associated primarily with subsistence agriculture, that is, where most farming is aimed at producing enough food energy to survive. The total absence of agriculture in an economically strong area does not cause famine; Arizona and other wealthy regions import the vast majority of their food, since such regions produce sufficient economic goods for trade.
Disasters, whether natural or man-made, have been associated with conditions of famine ever since humankind has been keeping written records. The Torah describes how "seven lean years" consumed the seven fat years, and "plagues of locusts" could eat all of the available food stuffs. War, in particular, was associated with famine, particularly in those times and places where warfare included attacks on land, by burning fields, or on those who tilled the soil.
As observed by the economist Amartya Sen, famine is sometimes a problem of food distribution and poverty. In certain cases, such as the Great Leap Forward, North Korea in the mid-1990s, or Zimbabwe in the early-2000s, famine can be caused as an unintentional result of government policy. Famine is sometimes used as a tool of repressive governments as a means to eliminate opponents, as in the Ukrainian famine of the 1930s. In other cases, such as Somalia, famine is a consequence of civil disorder as food distribution systems break down. Most cases are not simply the result of the excedence of the Earth's carrying capacity, with consideration given to ever-present economic inequities that have existed since early civilizations.
There are a number of ongoing famines caused by overpopulation, loss of arable land, war or political intervention.
Beginning in the 20th century, nitrogen fertilizers, new pesticides, desert farming, and other agricultural technologies began to be used as weapons against famine.
Between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%. These agricultural technologies temporarily increased crop yields, but there are signs as early as 1995 that not only are these technologies reaching their peak of assistance, but they may now be contributing to the decline of arable land (e.g. persistence of pesticides leading to soil contamination and decline of area available for farming. Developed nations have shared these technologies with developing nations with a famine problem, but there are ethical limits to pushing such technologies on lesser developed countries. This is often attributed to an association of inorganic fertilizers and pesticides with a lack of sustainability. In any case, these technological advances might not be influential in those famines which are the result of war. Similarly so, increased yield may not be helpful with certain distribution problems, especially those arising from political intervention.
David Pimentel, professor of ecology and agriculture at Cornell University, and Mario Giampietro, senior researcher at the National Research Institute on Food and Nutrition (INRAN), place in their study Food, Land, Population and the U.S. Economy the maximum U.S. population for a sustainable economy at 200 million. To achieve a sustainable economy and avert disaster, the United States must reduce its population by at least one-third, and world population will have to be reduced by two-thirds, says study.
The authors of this study believe that the mentioned agricultural crisis will only begin to impact us after 2020, and will not become critical until 2050. The oncoming peaking of global oil production (and subsequent decline of production), along with the peak of North American natural gas production will very likely precipitate this agricultural crisis much sooner than expected. Geologist Dale Allen Pfeiffer claims that coming decades could see spiraling food prices without relief and massive starvation on a global level such as never experienced before.
## Effects of famine
The demographic impacts of famine are sharp. Mortality is concentrated among children and the elderly. A consistent demographic fact is that in all recorded famines, male mortality exceeds female, even in those populations (such as northern India and Pakistan) where there is a normal times male longevity advantage. Reasons for this may include greater female resilience under the pressure of malnutrition, and the fact that women are more skilled at gathering and processing wild foods and other fall-back famine foods. Famine is also accompanied by lower fertility. Famines therefore leave the reproductive core of a population—adult women—lesser affected compared to other population categories, and post-famine periods are often characterized a "rebound" with increased births. Even though the theories of Thomas Malthus would predict that famines reduce the size of the population commensurate with available food resources, in fact even the most severe famines have rarely dented population growth for more than a few years. The mortality in China in 1958–61, Bengal in 1943, and Ethiopia in 1983–85 was all made up by a growing population over just a few years. Of greater long-term demographic impact is emigration: Ireland was chiefly depopulated after the 1840s famines by waves of emigration.
## Levels of food insecurity
In modern times, governments and non-governmental organizations that deliver famine relief have limited resources with which to address the multiple situations of food insecurity that are occurring simultaneously. Various methods of categorizing the gradations of food security have thus been used in order to most efficiently allocate food relief. One of the earliest were the Indian Famine Codes devised by the British in the 1880s. The Codes listed three stages of food insecurity: near-scarcity, scarcity and famine, and were highly influential in the creation of subsequent famine warning or measurement systems. The early warning system developed to monitor the region inhabited by the Turkana people in northern Kenya also has three levels, but links each stage to a pre-planned response to mitigate the crisis and prevent its deterioration.
The experiences of famine relief organizations throughout the world over the 1980s and 1990s resulted in at least two major developments: the "livelihoods approach" and the increased use of nutrition indicators to determine the severity of a crisis. Individuals and groups in food stressful situations will attempt to cope by rationing consumption, finding alternative means to supplement income, etc. before taking desperate measures, such as selling off plots of agricultural land. When all means of self-support are exhausted, the affected population begins to migrate in search of food or fall victim to outright mass starvation. Famine may thus be viewed partially as a social phenomenon, involving markets, the price of food, and social support structures. A second lesson drawn was the increased use of rapid nutrition assessments, in particular of children, to give a quantitative measure of the famine's severity.
Since 2004, many of the most important organizations in famine relief, such as the World Food Programme, Thom Bauermann and the U.S. Agency for International Development chris Scott, have adopted a five-level scale measuring intensity and magnitude. The intensity scale uses both livelihoods' measures and measurements of mortality and child malnutrition to categorize a situation as food secure, food insecure, food crisis, famine, severe famine, and extreme famine. The number of deaths determines the magnitude designation, with under 1000 fatalities defining a "minor famine" and a "catastrophic famine" resulting in over 1,000,000 deaths.
# Historical famine, by region
## Famine in Africa
In the mid-22nd century BC, a sudden and short-lived climatic change that caused reduced rainfall resulted in several decades of drought in Upper Egypt. The resulting famine and civil strife is believed to have been a major cause of the collapse of the Old Kingdom.
An account from the First Intermediate Period states, "All of Upper Egypt was dying of hunger and people were eating their children." In 1680s, famine extended across the entire Sahel, and in 1738 half the population of Timbuktu died of famine.
Historians of African famine have documented repeated famines in Ethiopia. Possibly the worst episode occurred in 1888 and succeeding years, as the epizootic rinderpest, introduced into Eritrea by infected cattle, spread southwards reaching ultimately as far as South Africa. In Ethiopia it was estimated that as much as 90 percent of the national herd died, rendering rich farmers and herders destitute overnight. This coincided with drought associated with an el Nino oscillation, human epidemics of smallpox, and in several countries, intense war. The great famine that afflicted Ethiopia from 1888 to 1892 cost it roughly
-ne-third of its population. In Sudan the year 1888 is remembered as the worst famine in history, on account of these factors and also the exactions imposed by the Mahdist state. Colonial "pacification" efforts often caused severe famine, as for example with the repression of the Maji Maji revolt in Tanganyika in 1906. The introduction of cash crops such as cotton, and forcible measures to impel farmers to grow these crops, also impoverished the peasantry in many areas, such as northern Nigeria, contributing to greater vulnerability to famine when severe drought struck in 1913.
However, for the middle part of the 20th century, agriculturalists, economists and geographers did not consider Africa to be famine prone (they were much more concerned about Asia). There were notable counter-examples, such as the famine in Rwanda during World War II and the Malawi famine of 1949, but most famines were localized and brief food shortages. The specter of famine recurred only in the early 1970s, when Ethiopia and the west African Sahel suffered drought and famine. The Ethiopian famine of that time was closely linked to the crisis of feudalism in that country, and in due course helped to bring about the downfall of the Emperor Haile Selassie. The Sahelian famine was associated with the slowly growing crisis of pastoralism in Africa, which has seen livestock herding decline as a viable way of life over the last two generations.
Since then, African famines have become more frequent, more widespread and more severe. Many African countries are not self-sufficient in food production, relying on income from cash crops to import food. Agriculture in Africa is susceptible to climatic fluctuations, especially droughts which can reduce the amount of food produced locally. Other agricultural problems include soil infertility, land degradation and erosion, and swarms of desert locusts which can destroy whole crops and livestock diseases. The most serious famines have been caused by a combination of drought, misguided economic policies, and conflict. The 1983–85 famine in Ethiopia, for example, was the outcome of all these three factors, made worse by the Communist government's censorship of the emerging crisis. In Sudan at the same date, drought and economic crisis combined with denials of any food shortage by the then-government of President Gaafar Nimeiry, to create a crisis that killed perhaps 250,000 people—and helped bring about a popular uprising that overthrew Nimeiry.
Numerous factors make the food security situation in Africa tenuous, including political instability, armed conflict and civil war, corruption and mismanagement in handling food supplies, and trade policies that harm African agriculture. An example of a famine created by human rights abuses is the 1998 Sudan famine. AIDS is also having long-term economic effects on agriculture by reducing the available workforce, and is creating new vulnerabilities to famine by overburdening poor households. On the other hand, in the modern history of Africa on quite a few occasions famines acted as a major source of acute political instability. In Africa, if current trends of population growth and soil degradation continue, the continent might
be able to feed just 25% of its population by 2025, according to UNU's Ghana-based Institute for Natural Resources in Africa.
Recent examples include Ethiopia in 1973 and mid-1980s, Sudan in the late-1970s and again in 1990 and 1998. The 1980 famine in Karamoja, Uganda was, in terms of mortality rates, one of the worst in history. 21% of the population died, including 60% of the infants.
In October 1984, television reports around the world carried footage of starving Ethiopians whose plight was centered around a feeding station near the town of Korem. BBC newsreader Michael Buerk gave moving commentary of the tragedy on 23 October 1984, which he described as a "biblical famine". This prompted the Band Aid single, which was organised by Bob Geldof and featured more than 20 other pop stars. The Live Aid concerts in London and Philadelphia raised further funds for the cause. An estimated 900,000 people die within one year as a result of the famine, but the tens of millions of pounds raised by Band Aid and Live Aid are widely believed to have saved the lives of around 6,000,000 more Ethiopians who were in danger of death.
More than 20 years on, famine and other forms of poverty are still affecting Ethiopia, but all concerned have insisted that the problems would have been far worse had it not been for Geldof and his fundraising causes.
## Famine in Asia
### China
Chinese scholars had kept count of 1,828 rampages by the famine since 108 B.C. to 1911 in one province or another — an average of close to one famine per year. From 1333 to 1337 a terrible famine killed 6,000,000 Chinese. The four famines of 1810, 1811, 1846, and 1849 are said to have killed not less than 45,000,000 people. China's Qing Dynasty bureaucracy, which devoted extensive attention to minimizing famines, is credited with averting a series of famines following El Niño-Southern Oscillation-linked droughts and floods. These events are comparable, though somewhat smaller in scale, to the ecological trigger events of China's vast 19th century famines. (Pierre-Etienne Will, Bureaucracy and Famine) Qing China carried out its relief efforts, which included vast shipments of food, a requirement that the rich open their storehouses to the poor, and price regulation, as part of a state guarantee of subsistence to the peasantry (known as ming-sheng).
When a stressed monarchy shifted from state management and direct shipments of grain to monetary charity in the mid-nineteenth century, the system broke down. Thus the 1867–68 famine under the Tongzhi Restoration was successfully relieved but the Great North China Famine of 1877–78 , caused by drought across northern China, was a vast catastrophe. The province of Shanxi was substantially depopulated as grains ran out, and desperately starving people stripped forests, fields, and their very houses for food. Estimated mortality is 9.5 to 13 million people.(Mike Davis, Late Victorian Holocausts)
The largest famine of the 20th century, and almost certainly of all time, was the 1958–61 Great Leap Forward famine in China. The immediate causes of this famine lay in Chairman Mao Zedong's ill-fated attempt to transform China from an agricultural nation, Communist Party cadres across China insisted that peasants abandon their farms for collective farms, and begin to produce steel in small foundries, often melting down their farm instruments in the process. Collectivization undermined incentives for the investment of labor and resources in agriculture; unrealistic plans for decentralized metal production sapped needed labor; unfavorable weather conditions; and communal dining halls encouraged overconsumption of available food (see Chang, G, and Wen, G (1997), "Communal dining and the Chinese Famine 1958-1961" ). Such was the centralized control of information and the intense pressure on party cadres to report only good news—such as production quotas met or exceeded—that information about the escalating disaster was effectively suppressed. When the leadership did become aware of the scale of the famine, it did little to respond, and continued to ban any discussion of the cataclysm. This blanket suppression of news was so effective that very few Chinese citizens were aware of the scale of the famine, and the greatest peacetime demographic disaster of the 20th century only became widely known twenty years later, when the veil of censorship began to lift.
The 1958–61 famine is estimated to have caused excess mortality of about 30 million, with a further 30 million cancelled or delayed births. It was only when the famine had wrought its worst that Mao reversed the agricultural collectivization policies, which were effectively dismantled in 1978. China has not experienced a major famine since 1961 (Woo-Cummings, 2002).
### India
Owing to its almost entire dependence upon the monsoon rains, India is more liable than any other country in the world to crop failures, which upon occasion deepen into famine. There were 14 famines in India between 11th and 17th century (Bhatia, 1985). For example, during the 1022-1033 Great famines in India entire provinces were depopulated. Famine in Deccan killed at least 2 million people in 1702-1704. B.M. Bhatia believes that the earlier famines were localised, and it was only after 1860, during the British rule, that famine came to signify general shortage of foodgrains in the country. There were approximately 25 major famines spread through states such as Tamil Nadu in the south, and Bihar and Bengal in the east during the latter half of the 19th century.
Romesh Dutt argued as early as 1900, and present-day scholars such as Amartya Sen agree, that the famines were a product of both uneven rainfall and British economic and administrative policies, which since 1857 had led to the seizure and conversion of local farmland to foreign-owned plantations, restrictions on internal trade, heavy taxation of Indian citizens to support unsuccessful British expeditions in Afghanistan (see The Second Anglo-Afghan War), inflationary measures that increased the price of food, and substantial exports of staple crops from India to Britain. (Dutt, 1900 and 1902; Srivastava, 1968; Sen, 1982; Bhatia, 1985.) Some British citizens, such as William Digby, agitated for policy reforms and famine relief, but Lord Lytton, the governing British viceroy in India, opposed such changes in the belief that they would stimulate shirking by Indian workers. The first, the Bengal famine of 1770, is estimated to have taken around 10 million lives — one-third of Bengal's population at the time. The famines continued until independence in 1947, with the Bengal Famine of 1943–44— even though there were no crop failures —killing 1.5 million to 3 million Bengalis during World War II.
The observations of the Famine Commission of 1880 support the notion that food distribution is more to blame for famines than food scarcity. They observed that each province in British India, including Burma, had a surplus of foodgrains, and the annual surplus was 5.16 million tons (Bhatia, 1970). At that time, annual export of rice and other grains from India was approximately one million tons.
In 1966, there was a close call in Bihar, when the United States allocated 900,000 tons of grain to fight the famine.
### North Korea
Famine struck North Korea in the mid-1990s, set off by unprecedented floods. This autarkic urban, industrial society had achieved food self-sufficiency in prior decades through a massive industrialization of agriculture. However, the economic system relied on massive concessionary inputs of fossil fuels, primarily from the Soviet Union and the People's Republic of China. When the Soviet collapse and China's marketization switched trade to a hard currency, full price basis, North Korea's economy collapsed. The vulnerable agricultural sector experienced a massive failure in 1995–96, expanding to full-fledged famine by 1996–99. An estimated 600,000 died of starvation (other estimates range from 200,000 to 3.5 million). North Korea has not yet resumed its food self-sufficiency and relies on external food aid from China, Japan, South Korea and the United States. Recently, North Korea requested that food supplies no longer be delivered. (Woo-Cummings, 2002)
### Vietnam
Various famines have occurred in Vietnam. Japanese occupation during World War II caused the Vietnamese Famine of 1945, which caused 2 million deaths. Following the unification of the country after the Vietnam War, Vietnam briefly experienced a food shortage in the 1980s, which prompted many people to flee the country.
## Famine in Europe
### Western Europe
The Great Famine of 1315–1317 (or to 1322) was the first crisis that would strike Europe in the 14th century, millions in northern Europe would die over an extended number of years, marking a clear end to the earlier period of growth and prosperity during the 11th and 12th centuries. Starting with bad weather in the spring of 1315, universal crop failures lasted until the summer of 1317, from which Europe did not fully recover until 1322. It was a period marked by extreme levels of criminal activity, disease and mass death, infanticide, and cannibalism. It had consequences for Church, State, European society and future calamities to follow in the 14th century.
The 17th century was a period of change for the food producers of Europe. For centuries they had lived primarily as subsistence farmers in a feudal system. They had obligations to their lords, who had suzerainty over the land tilled by their peasants. The lord of a fief would take a portion of the crops and livestock produced during the year. Peasants generally tried to minimize the amount of work they had to put into agricultural food production. Their lords rarely pressured them to increase their food output, except when the population started to increase, at which time the peasants were likely to increase the production themselves. More land would be added to cultivation until there was no more available and the peasants were forced to take up more labour-intensive methods of production. Nonetheless, they generally tried to work as little as possible, valuing their time to do other things, such as hunting, fishing or relaxing, as long as they had enough food to feed their families. It was not in their interest to produce more than they could eat or store themselves.
During the 17th century, continuing the trend of previous centuries, there was an increase in market-driven agriculture. Farmers, people who rented land in order to make a profit off of the product of the land, employing wage labour, became increasingly common, particularly in western Europe. It was in their interest to produce as much as possible on their land in order to sell it to areas that demanded that product. They produced guaranteed surpluses of their crop every year if they could. Farmers paid their labourers in money, increasing the commercialization of rural society. This commercialization had a profound impact on the behaviour of peasants. Farmers were interested in increasing labour input into their lands, not decreasing it as subsistence peasants were.
Subsistence peasants were also increasingly forced to commercialize their activities because of increasing taxes. Taxes that had to be paid to central governments in money forced the peasants to produce crops to sell. Sometimes they produced industrial crops, but they would find ways to increase their production in order to meet both their subsistence requirements as well as their tax obligations. Peasants also used the new money to purchase manufactured goods. The agricultural and social developments encouraging increased food production were gradually taking place throughout the sixteenth century, but were spurred on more directly by the adverse conditions for food production that Europe found itself in the early seventeenth century — there was a general cooling trend in the Earth's temperature starting at the beginning end of the sixteenth century.
The 1590s saw the worst famines in centuries across all of Europe, except in certain areas, notably the Netherlands. Famine had been relatively rare during the 16th century. The economy and population had grown steadily as subsistence populations tend to when there is an extended period of relative peace (most of the time). Subsistence peasant populations will almost always increase when possible since the peasants will try to spread the work to as many hands as possible. Although peasants in areas of high population density, such as northern Italy, had learned to increase the yields of their lands through techniques such as promiscuous culture, they were still quite vulnerable to famines, forcing them to work their land even more intensively.
Famine is a very destabilizing and devastating occurrence. The prospect of starvation led people to take desperate measures. When scarcity of food became apparent to peasants, they would sacrifice long-term prosperity for short-term survival. They would kill their draught animals, leading to lowered production in subsequent years. They would eat their seed corn, sacrificing next year's crop in the hope that more seed could be found. Once those means had been exhausted, they would take to the road in search of food. They migrated to the cities where merchants from other areas would be more likely to sell their food, as cities had a stronger purchasing power than did rural areas. Cities also administered relief programs and bought grain for their populations so that they could keep order. With the confusion and desperation of the migrants, crime would often follow them. Many peasants resorted to banditry in order to acquire enough to eat.
One famine would often lead to difficulties in following years because of lack of seed stock or disruption of routine, or perhaps because of less-available labour. Famines were often interpreted as signs of God's displeasure. They were seen as the removal, by God, of His gifts to the people of the Earth. Elaborate religious processions and rituals were made to prevent God's wrath in the form of famine.
The great famine of the 1590s began the period of famine and decline in the 17th century. The price of grain, all over Europe was high, as was the population. Various types of people were vulnerable to the succession of bad harvests that occurred throughout the 1590s in different regions. The increasing number of wage labourers in the countryside were vulnerable because they had no food of their own, and their meager living was not enough to purchase the expensive grain of a bad-crop year. Town labourers were also at risk because their wages would be insufficient to cover the cost of grain, and, to make matters worse, they often received less money in bad-crop years since the disposable income of the wealthy was spent on grain. Often, unemployment would be the result of the increase in grain prices, leading to ever-increasing numbers of urban poor.
All areas of Europe were badly affected by the famine in these periods, especially rural areas. The Netherlands was able to escape most of the damaging effects of the famine, though the 1590s were still difficult years there. Actual famine did not occur, for the Amsterdam grain trade guaranteed that there would always be something to eat in the Netherlands although hunger was prevalent.
The Netherlands had the most commercialized agriculture in all of Europe at this time, growing many industrial crops, such as flax, hemp, and hops. Agriculture became increasingly specialized and efficient. As a result, productivity and wealth increased, allowing the Netherlands to maintain a steady food supply. By the 1620s, the economy was even more developed, so the country was able to avoid the hardships of that period of famine with even greater impunity.
The years around 1620 saw another period of famines sweep across Europe. These famines were generally less severe than the famines of twenty-five years earlier, but they were nonetheless quite serious in many areas. Perhaps the worst famine since 1600, the great famine in Finland in 1696, killed a third of the population. Template:PDFlink
The period of 1740–43 saw frigid winters and summer droughts which led to famine across Europe leading to a major spike in mortality.(cited in Davis, Late Victorian Holocausts, 281)
Other areas of Europe have known famines much more recently. France saw famines as recently as the nineteenth century. Famine still occurred in eastern Europe during the 20th century.
The frequency of famine can vary with climate changes. For example, during the little ice age of the 15th century to the 18th century, European famines grew more frequent than they had been during previous centuries.
Because of the frequency of famine in many societies, it has long been a chief concern of governments and other authorities. In pre-industrial Europe, preventing famine, and ensuring timely food supplies, was one of the chief concerns of many governments, which employed various tools to alleviate famines, including price controls, purchasing stockpiles of food from other areas, rationing, and regulation of production. Most governments were concerned by famine because it could lead to revolt and other forms of social disruption.
In contrast, the Great Irish Famine, 1845-1849, was in no small part the result of policies of the Whig government of the United Kingdom under Lord Russell. Unlike in Britain, the land in Ireland was owned mostly by Anglican people of English descent, who did not identify culturally or ethnically with their peasants. The landlords were known as the Anglo-Irish. As the landowners felt no compunction to use their political clout to aid their tenants, the British government's expedient response to the food crisis in Ireland was to leave the matter solely to market forces to decide. A strict free-market approach, aided by the British army guarding ports and food depots from the starving crowds, ensured food exports continued as before, and even increased during the famine period. The immediate effect was 1,000,000 dead and another 1,000,000 refugees fleeing to Britain and the United States. After the famine passed, infertility caused by famine, diseases and immigration spurred by the landlord-run economy being so thoroughly undermined, caused the population to enter into a 100-year decline. It was not until the 1970's that the population of Ireland, then at half of what it had been before the famine, began to rise again. This period of Irish population decline after the famine was at a time when the European population doubled and the English population increased fourfold. This left the country severely underpopulated. The population decline continued in parts of the country worst affected by the famine until the 1990s - 150 years after the famine and the British government's laissez-faire economic policy. Before the Hunger, Ireland's population was over half of England's. Today it is an eighth. The population of Ireland is 6 million but there are over 80 million more people of Irish descent outside of Ireland. That is 20 more times the population of Ireland.
Famine returned to the Netherlands during World War II in what was known as the Hongerwinter. It was the last famine of Europe, in which approximately 30,000 people died of starvation. Some other areas of Europe also experienced famine at the same time.
The harvest failures were devastating for the northern Italian economy. The economy of the area had recovered well from the previous famines, but the famines from 1618 to 1621 coincided because of a period of war in the area. The economy did not recover fully for centuries. There were serious famines in the late-1640s and less severe ones in the 1670s throughout northern Italy.
From 1536 England began legislating Poor Laws which put a legal responsibility on the rich, at a parish level, to maintain the poor of that parish. English agriculture lagged behind the Netherlands, but by 1650 their agricultural industry was commercialized on a wide scale. The last peace-time famine in England was in 1623–24. There were still periods of hunger, as in the Netherlands, but there were no more famines as such. Rising population levels continued to put a strain on food security, despite potatoes becoming increasingly important in the diet of the poor. On balance, potatoes increased food security in England where they never replaced bread as the staple of the poor. Climate conditions were never likely to simultaneously be catastrophic for both the wheat and potato crops.
In 1783 the volcano Laki in south-central Iceland erupted. The lava caused little direct damage, but ash and sulfur dioxide spewed out over most of the country, causing three-quarters of the island's livestock to perish. In the following famine, around ten thousand people died, one-fifth of the population of Iceland.
### Russia and the USSR
Droughts and famines in Imperial Russia are known to have happened every 10 to 13 years, with average droughts happening every 5 to 7 years. Famines continued in the Soviet era, the most famous one being the Holodomor in Ukraine (1932–1933). The last major famine in the USSR happened in 1947 due to the severe drought.
# Notes
- ↑ Poor studies will always be with us
- ↑ The facts on malnutrition & famine
- ↑ Rising food prices curb aid to global poor
- ↑ The limits of a Green Revolution?
- ↑ How Much Did the Green Revolution Matter?
- ↑ Eating Fossil Fuels | EnergyBulletin.net
- ↑ Peak Oil: the threat to our food security
- ↑ Agriculture Meets Peak Oil
- ↑ Len Milich: Anthropogenic Desertification vs ‘Natural’ Climate Trends
- ↑ El Niño and Drought Early Warning in Ethiopia
- ↑ See, for example, Andrey Korotayev and Daria Khaltourina Secular Cycles and Millennial Trends in Africa. Moscow: Russia, 2006.
- ↑ Africa may be able to feed only 25% of its population by 2025
- ↑ China: Land of Famine
- ↑ Fearfull Famines of the Past
- ↑ Famine - Encyclopaedia Britannica 1911 | Famine
# Overview
A famine is a widespread shortage of food that may apply to any faunal species, which phenomenon is usually accompanied by regional malnutrition, starvation, epidemic, and increased mortality.
Although most famines coincide with regional shortages of food, famine in some human populations has occurred amid plenty or on account of acts of economic or military policy that have deprived certain populations of sufficient food to ensure survival. Historically, famines have occurred because of drought, crop failure, pestilence, and man-made causes such as war or misguided economic policies. Bad harvests, overpopulation, and epidemic diseases like the Black Death helped cause hundreds of famines in Europe during the Middle Ages, including 95 in the British Isles and 75 in France.[1][2]
During the 20th century, an estimated 70 million people died from famines across the world, of whom an estimated 30 million died during the famine of 1958–61 in China. The other most notable famines of the century included the 1942–1945 disaster in Bengal, famines in China in 1928 and 1942, and a sequence of man-made famines in the Soviet Union, including the Holodomor, Stalin's famine inflicted on Ukraine in 1932–33. A few of the great famines of the late 20th century were: the Biafran famine in the 1960s, the disaster in Cambodia in the 1970s, the Ethiopian famine of 1983–85 and the North Korean famine of the 1990s.
Famine can be induced by a human population beyond the regional carrying capacity to provide food resources. An alternate view of famine is a failure of the poor to command sufficient resources to acquire essential food (the "entitlement theory" of Amartya Sen), analyses of famine that focused on the political-economic processes driving the creation of famine, an understanding of the complex reasons for mortality in famines, an appreciation of the extent to which famine-vulnerable communities have well-developed strategies for coping with the threat of famine, and the role of warfare and terrorism in creating famine. Modern relief agencies categorize various gradations of famine according to a famine scale.
Many areas that suffered famines in the past have protected themselves through technological and social development. The first area in Europe to eliminate famine was the Netherlands, which saw its last peacetime famines in the early 17th century as it became a major economic power and established a complex political organization. Noting that many famines occur under dictatorship, colonial rule[citation needed], or during war, Amartya Sen has posited that no functioning democracy has suffered a famine in modern times.
# Characteristics of famine
Today, famine strikes Sub-Saharan African countries the hardest, but with exhaustion of food resources, overdrafting of groundwater, wars, internal struggles, and economic failure, famine continues to be a worldwide problem with millions of individuals suffering.[3] These famines cause widespread malnutrition and impoverishment; The famine in Ethiopia in the 1980s had an immense death toll, although Asian famines of the 20th century have also produced extensive death tolls. Modern African famines are characterised by widespread destitution and malnutrition, with heightened mortality confined to young children. Relief technologies including immunization, improved public health infrastructure, general food rations and supplementary feeding for vulnerable children, has blunted the mortality impacts of famines, while leaving their economic causes and consequences unchanged. Humanitarian crises also arise from civil wars, refugee flows and episodes of extreme violence and state collapse, creating famine conditions among the affected populations.
Despite repeated stated intentions by the world's leaders to end hunger and famine, famine remains a chronic threat in much of Africa and Asia. In July 2005, the Famine Early Warning Systems Network labelled Niger with emergency status, as well as Chad, Ethiopia, South Sudan, Somalia and Zimbabwe. In January 2006, the United Nations Food and Agriculture Organization warned that 11 million people in Somalia, Kenya, Djibouti and Ethiopia were in danger of starvation due to the combination of severe drought and military conflicts. [1] In 2006, the most serious humanitarian crisis in Africa is in Sudan's region Darfur.
Some believe that the Green Revolution was an answer to famine in the 1970s and 1980s. The Green Revolution began in the 20th century with hybrid strains of high-yielding crops. Between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%.[4][5] Some criticize the process, stating that these new high-yielding crops require more chemical fertilizers and pesticides, which can harm the environment. However, it was an option for developing nations suffering from famine. These high-yielding crops make it technically possible to feed much of the world population. They can be developed to provide enhanced nutrition, and a well-nourished, well-developed population would emerge. Some say that the problems of famine and ill-nourishment are the results of ethical dilemmas over using the technologies we have, as well as cultural and class differences. Furthermore, there are indications that regional food production has peaked in many world sectors, due to certain strategies associated with intensive agriculture such as groundwater overdrafting and overuse of pesticides and other agricultural chemicals.
Frances Moore Lappé, later co-founder of the Institute for Food and Development Policy (Food First) argued in Diet for a Small Planet (1971) that vegetarian diets can provide food for larger populations, with the same resources, compared to omnivorous diets.
Noting that modern famines are sometimes the outcome of misguided economic policies, political design to impoverish or marginalize certain populations, or acts of war, political economists have investigated the political conditions under which famine is prevented. Amartya Sen states that the liberal institutions that exist in India, including competitive elections and a free press, have played a major role in preventing famine in that country since independence. Alex de Waal has developed this theory to focus on the "political contract" between rulers and people that ensures famine prevention, noting the rarity of such political contracts in Africa, and the danger that international relief agencies will undermine such contracts through removing the locus of accountability for famines from national governments.
## Causes of famine
The cause of famine is a combination of political, economic, and biological factors. Because of food aid, improved storage and preservation food processing- it is a popular misconception that the only cause of famine is insufficient food supply, or in biological terms, a population beyond its regional carrying capacity. Famines can be exacerbated by poor governance or inadequate logistics for food distribution. In most modern cases, it is political strife, poverty, and violence that disrupts the agricultural and food distribution processes. Modern famines have often occurred in nations that, as a whole, were not initially suffering a shortage of food. One of the largest historical famines (proportional to the affected population) was the Great Irish Famine, 1845-1849, which began in 1845 and occurred as food was being shipped from Ireland to England because the English could afford to pay higher prices. The largest famine ever (in absolute terms) was the Chinese famine of 1958–61 that occurred as a result of the Great Leap Forward. In a similar manner, the 1973 famine in Ethiopia was concentrated in the Wollo region, although food was being shipped out of Wollo to the capital city of Addis Ababa where it could command higher prices. In contrast, at the same time that the citizens of the dictatorships of Ethiopia and Sudan had massive famines in the late-1970s and early-1980s, the democracies of Botswana and Zimbabwe avoided them, despite having worse drops in national food production. This was possible through the simple step of creating short-term employment for the worst-affected groups, thus ensuring a minimal amount of income to buy food, for the duration of the localized food disruption and was taken under criticism from opposition political parties and intense media coverage.
The failure of a harvest or the change in conditions, such as drought, can create a situation whereby large numbers of people live where the carrying capacity of the land has dropped radically. Famine is then associated primarily with subsistence agriculture, that is, where most farming is aimed at producing enough food energy to survive. The total absence of agriculture in an economically strong area does not cause famine; Arizona and other wealthy regions import the vast majority of their food, since such regions produce sufficient economic goods for trade.
Disasters, whether natural or man-made, have been associated with conditions of famine ever since humankind has been keeping written records. The Torah describes how "seven lean years" consumed the seven fat years, and "plagues of locusts" could eat all of the available food stuffs. War, in particular, was associated with famine, particularly in those times and places where warfare included attacks on land, by burning fields, or on those who tilled the soil.
As observed by the economist Amartya Sen, famine is sometimes a problem of food distribution and poverty. In certain cases, such as the Great Leap Forward, North Korea in the mid-1990s, or Zimbabwe in the early-2000s, famine can be caused as an unintentional result of government policy. Famine is sometimes used as a tool of repressive governments as a means to eliminate opponents, as in the Ukrainian famine of the 1930s. In other cases, such as Somalia, famine is a consequence of civil disorder as food distribution systems break down. Most cases are not simply the result of the excedence of the Earth's carrying capacity, with consideration given to ever-present economic inequities that have existed since early civilizations.
There are a number of ongoing famines caused by overpopulation, loss of arable land, war or political intervention.
Beginning in the 20th century, nitrogen fertilizers, new pesticides, desert farming, and other agricultural technologies began to be used as weapons against famine.
Between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%. These agricultural technologies temporarily increased crop yields, but there are signs as early as 1995 that not only are these technologies reaching their peak of assistance, but they may now be contributing to the decline of arable land (e.g. persistence of pesticides leading to soil contamination and decline of area available for farming. Developed nations have shared these technologies with developing nations with a famine problem, but there are ethical limits to pushing such technologies on lesser developed countries. This is often attributed to an association of inorganic fertilizers and pesticides with a lack of sustainability. In any case, these technological advances might not be influential in those famines which are the result of war. Similarly so, increased yield may not be helpful with certain distribution problems, especially those arising from political intervention.
David Pimentel, professor of ecology and agriculture at Cornell University, and Mario Giampietro, senior researcher at the National Research Institute on Food and Nutrition (INRAN), place in their study Food, Land, Population and the U.S. Economy the maximum U.S. population for a sustainable economy at 200 million.[6] To achieve a sustainable economy and avert disaster, the United States must reduce its population by at least one-third, and world population will have to be reduced by two-thirds, says study.[7]
The authors of this study believe that the mentioned agricultural crisis will only begin to impact us after 2020, and will not become critical until 2050. The oncoming peaking of global oil production (and subsequent decline of production), along with the peak of North American natural gas production will very likely precipitate this agricultural crisis much sooner than expected. Geologist Dale Allen Pfeiffer claims that coming decades could see spiraling food prices without relief and massive starvation on a global level such as never experienced before.[8]
## Effects of famine
The demographic impacts of famine are sharp. Mortality is concentrated among children and the elderly. A consistent demographic fact is that in all recorded famines, male mortality exceeds female, even in those populations (such as northern India and Pakistan) where there is a normal times male longevity advantage. Reasons for this may include greater female resilience under the pressure of malnutrition, and the fact that women are more skilled at gathering and processing wild foods and other fall-back famine foods. Famine is also accompanied by lower fertility. Famines therefore leave the reproductive core of a population—adult women—lesser affected compared to other population categories, and post-famine periods are often characterized a "rebound" with increased births. Even though the theories of Thomas Malthus would predict that famines reduce the size of the population commensurate with available food resources, in fact even the most severe famines have rarely dented population growth for more than a few years. The mortality in China in 1958–61, Bengal in 1943, and Ethiopia in 1983–85 was all made up by a growing population over just a few years. Of greater long-term demographic impact is emigration: Ireland was chiefly depopulated after the 1840s famines by waves of emigration.
## Levels of food insecurity
In modern times, governments and non-governmental organizations that deliver famine relief have limited resources with which to address the multiple situations of food insecurity that are occurring simultaneously. Various methods of categorizing the gradations of food security have thus been used in order to most efficiently allocate food relief. One of the earliest were the Indian Famine Codes devised by the British in the 1880s. The Codes listed three stages of food insecurity: near-scarcity, scarcity and famine, and were highly influential in the creation of subsequent famine warning or measurement systems. The early warning system developed to monitor the region inhabited by the Turkana people in northern Kenya also has three levels, but links each stage to a pre-planned response to mitigate the crisis and prevent its deterioration.
The experiences of famine relief organizations throughout the world over the 1980s and 1990s resulted in at least two major developments: the "livelihoods approach" and the increased use of nutrition indicators to determine the severity of a crisis. Individuals and groups in food stressful situations will attempt to cope by rationing consumption, finding alternative means to supplement income, etc. before taking desperate measures, such as selling off plots of agricultural land. When all means of self-support are exhausted, the affected population begins to migrate in search of food or fall victim to outright mass starvation. Famine may thus be viewed partially as a social phenomenon, involving markets, the price of food, and social support structures. A second lesson drawn was the increased use of rapid nutrition assessments, in particular of children, to give a quantitative measure of the famine's severity.
Since 2004, many of the most important organizations in famine relief, such as the World Food Programme, Thom Bauermann and the U.S. Agency for International Development chris Scott, have adopted a five-level scale measuring intensity and magnitude. The intensity scale uses both livelihoods' measures and measurements of mortality and child malnutrition to categorize a situation as food secure, food insecure, food crisis, famine, severe famine, and extreme famine. The number of deaths determines the magnitude designation, with under 1000 fatalities defining a "minor famine" and a "catastrophic famine" resulting in over 1,000,000 deaths.
# Historical famine, by region
## Famine in Africa
In the mid-22nd century BC, a sudden and short-lived climatic change that caused reduced rainfall resulted in several decades of drought in Upper Egypt. The resulting famine and civil strife is believed to have been a major cause of the collapse of the Old Kingdom.
An account from the First Intermediate Period states, "All of Upper Egypt was dying of hunger and people were eating their children." In 1680s, famine extended across the entire Sahel, and in 1738 half the population of Timbuktu died of famine.[9]
Historians of African famine have documented repeated famines in Ethiopia. Possibly the worst episode occurred in 1888 and succeeding years, as the epizootic rinderpest, introduced into Eritrea by infected cattle, spread southwards reaching ultimately as far as South Africa. In Ethiopia it was estimated that as much as 90 percent of the national herd died, rendering rich farmers and herders destitute overnight. This coincided with drought associated with an el Nino oscillation, human epidemics of smallpox, and in several countries, intense war. The great famine that afflicted Ethiopia from 1888 to 1892 cost it roughly
one-third of its population.[10] In Sudan the year 1888 is remembered as the worst famine in history, on account of these factors and also the exactions imposed by the Mahdist state. Colonial "pacification" efforts often caused severe famine, as for example with the repression of the Maji Maji revolt in Tanganyika in 1906. The introduction of cash crops such as cotton, and forcible measures to impel farmers to grow these crops, also impoverished the peasantry in many areas, such as northern Nigeria, contributing to greater vulnerability to famine when severe drought struck in 1913.
However, for the middle part of the 20th century, agriculturalists, economists and geographers did not consider Africa to be famine prone (they were much more concerned about Asia).[citation needed] There were notable counter-examples, such as the famine in Rwanda during World War II and the Malawi famine of 1949, but most famines were localized and brief food shortages. The specter of famine recurred only in the early 1970s, when Ethiopia and the west African Sahel suffered drought and famine. The Ethiopian famine of that time was closely linked to the crisis of feudalism in that country, and in due course helped to bring about the downfall of the Emperor Haile Selassie. The Sahelian famine was associated with the slowly growing crisis of pastoralism in Africa, which has seen livestock herding decline as a viable way of life over the last two generations.
Since then, African famines have become more frequent, more widespread and more severe. Many African countries are not self-sufficient in food production, relying on income from cash crops to import food. Agriculture in Africa is susceptible to climatic fluctuations, especially droughts which can reduce the amount of food produced locally. Other agricultural problems include soil infertility, land degradation and erosion, and swarms of desert locusts which can destroy whole crops and livestock diseases. The most serious famines have been caused by a combination of drought, misguided economic policies, and conflict. The 1983–85 famine in Ethiopia, for example, was the outcome of all these three factors, made worse by the Communist government's censorship of the emerging crisis. In Sudan at the same date, drought and economic crisis combined with denials of any food shortage by the then-government of President Gaafar Nimeiry, to create a crisis that killed perhaps 250,000 people—and helped bring about a popular uprising that overthrew Nimeiry.
Numerous factors make the food security situation in Africa tenuous, including political instability, armed conflict and civil war, corruption and mismanagement in handling food supplies, and trade policies that harm African agriculture. An example of a famine created by human rights abuses is the 1998 Sudan famine. AIDS is also having long-term economic effects on agriculture by reducing the available workforce, and is creating new vulnerabilities to famine by overburdening poor households. On the other hand, in the modern history of Africa on quite a few occasions famines acted as a major source of acute political instability.[11] In Africa, if current trends of population growth and soil degradation continue, the continent might
be able to feed just 25% of its population by 2025, according to UNU's Ghana-based Institute for Natural Resources in Africa.[12]
Recent examples include Ethiopia in 1973 and mid-1980s, Sudan in the late-1970s and again in 1990 and 1998. The 1980 famine in Karamoja, Uganda was, in terms of mortality rates, one of the worst in history. 21% of the population died, including 60% of the infants. [2]
In October 1984, television reports around the world carried footage of starving Ethiopians whose plight was centered around a feeding station near the town of Korem. BBC newsreader Michael Buerk gave moving commentary of the tragedy on 23 October 1984, which he described as a "biblical famine". This prompted the Band Aid single, which was organised by Bob Geldof and featured more than 20 other pop stars. The Live Aid concerts in London and Philadelphia raised further funds for the cause. An estimated 900,000 people die within one year as a result of the famine, but the tens of millions of pounds raised by Band Aid and Live Aid are widely believed to have saved the lives of around 6,000,000 more Ethiopians who were in danger of death.
More than 20 years on, famine and other forms of poverty are still affecting Ethiopia, but all concerned have insisted that the problems would have been far worse had it not been for Geldof and his fundraising causes.
## Famine in Asia
### China
Chinese scholars had kept count of 1,828 rampages by the famine since 108 B.C. to 1911 in one province or another — an average of close to one famine per year.[13] From 1333 to 1337 a terrible famine killed 6,000,000 Chinese. The four famines of 1810, 1811, 1846, and 1849 are said to have killed not less than 45,000,000 people.[14] China's Qing Dynasty bureaucracy, which devoted extensive attention to minimizing famines, is credited with averting a series of famines following El Niño-Southern Oscillation-linked droughts and floods. These events are comparable, though somewhat smaller in scale, to the ecological trigger events of China's vast 19th century famines. (Pierre-Etienne Will, Bureaucracy and Famine) Qing China carried out its relief efforts, which included vast shipments of food, a requirement that the rich open their storehouses to the poor, and price regulation, as part of a state guarantee of subsistence to the peasantry (known as ming-sheng).
When a stressed monarchy shifted from state management and direct shipments of grain to monetary charity in the mid-nineteenth century, the system broke down. Thus the 1867–68 famine under the Tongzhi Restoration was successfully relieved but the Great North China Famine of 1877–78 , caused by drought across northern China, was a vast catastrophe. The province of Shanxi was substantially depopulated as grains ran out, and desperately starving people stripped forests, fields, and their very houses for food. Estimated mortality is 9.5 to 13 million people.(Mike Davis, Late Victorian Holocausts)
The largest famine of the 20th century, and almost certainly of all time, was the 1958–61 Great Leap Forward famine in China. The immediate causes of this famine lay in Chairman Mao Zedong's ill-fated attempt to transform China from an agricultural nation, Communist Party cadres across China insisted that peasants abandon their farms for collective farms, and begin to produce steel in small foundries, often melting down their farm instruments in the process. Collectivization undermined incentives for the investment of labor and resources in agriculture; unrealistic plans for decentralized metal production sapped needed labor; unfavorable weather conditions; and communal dining halls encouraged overconsumption of available food (see Chang, G, and Wen, G (1997), "Communal dining and the Chinese Famine 1958-1961" ). Such was the centralized control of information and the intense pressure on party cadres to report only good news—such as production quotas met or exceeded—that information about the escalating disaster was effectively suppressed. When the leadership did become aware of the scale of the famine, it did little to respond, and continued to ban any discussion of the cataclysm. This blanket suppression of news was so effective that very few Chinese citizens were aware of the scale of the famine, and the greatest peacetime demographic disaster of the 20th century only became widely known twenty years later, when the veil of censorship began to lift.
The 1958–61 famine is estimated to have caused excess mortality of about 30 million, with a further 30 million cancelled or delayed births. It was only when the famine had wrought its worst that Mao reversed the agricultural collectivization policies, which were effectively dismantled in 1978. China has not experienced a major famine since 1961 (Woo-Cummings, 2002).
### India
Owing to its almost entire dependence upon the monsoon rains, India is more liable than any other country in the world to crop failures, which upon occasion deepen into famine.[15] There were 14 famines in India between 11th and 17th century (Bhatia, 1985). For example, during the 1022-1033 Great famines in India entire provinces were depopulated. Famine in Deccan killed at least 2 million people in 1702-1704. B.M. Bhatia believes that the earlier famines were localised, and it was only after 1860, during the British rule, that famine came to signify general shortage of foodgrains in the country. There were approximately 25 major famines spread through states such as Tamil Nadu in the south, and Bihar and Bengal in the east during the latter half of the 19th century.
Romesh Dutt argued as early as 1900, and present-day scholars such as Amartya Sen agree, that the famines were a product of both uneven rainfall and British economic and administrative policies, which since 1857 had led to the seizure and conversion of local farmland to foreign-owned plantations, restrictions on internal trade, heavy taxation of Indian citizens to support unsuccessful British expeditions in Afghanistan (see The Second Anglo-Afghan War), inflationary measures that increased the price of food, and substantial exports of staple crops from India to Britain. (Dutt, 1900 and 1902; Srivastava, 1968; Sen, 1982; Bhatia, 1985.) Some British citizens, such as William Digby, agitated for policy reforms and famine relief, but Lord Lytton, the governing British viceroy in India, opposed such changes in the belief that they would stimulate shirking by Indian workers. The first, the Bengal famine of 1770, is estimated to have taken around 10 million lives — one-third of Bengal's population at the time. The famines continued until independence in 1947, with the Bengal Famine of 1943–44— even though there were no crop failures —killing 1.5 million to 3 million Bengalis during World War II.
The observations of the Famine Commission of 1880 support the notion that food distribution is more to blame for famines than food scarcity. They observed that each province in British India, including Burma, had a surplus of foodgrains, and the annual surplus was 5.16 million tons (Bhatia, 1970). At that time, annual export of rice and other grains from India was approximately one million tons.
In 1966, there was a close call in Bihar, when the United States allocated 900,000 tons of grain to fight the famine.
### North Korea
Famine struck North Korea in the mid-1990s, set off by unprecedented floods. This autarkic urban, industrial society had achieved food self-sufficiency in prior decades through a massive industrialization of agriculture. However, the economic system relied on massive concessionary inputs of fossil fuels, primarily from the Soviet Union and the People's Republic of China. When the Soviet collapse and China's marketization switched trade to a hard currency, full price basis, North Korea's economy collapsed. The vulnerable agricultural sector experienced a massive failure in 1995–96, expanding to full-fledged famine by 1996–99. An estimated 600,000 died of starvation (other estimates range from 200,000 to 3.5 million).[16] North Korea has not yet resumed its food self-sufficiency and relies on external food aid from China, Japan, South Korea and the United States. Recently, North Korea requested that food supplies no longer be delivered. (Woo-Cummings, 2002)
### Vietnam
Various famines have occurred in Vietnam. Japanese occupation during World War II caused the Vietnamese Famine of 1945, which caused 2 million deaths. Following the unification of the country after the Vietnam War, Vietnam briefly experienced a food shortage in the 1980s, which prompted many people to flee the country.
## Famine in Europe
### Western Europe
The Great Famine of 1315–1317 (or to 1322) was the first crisis that would strike Europe in the 14th century, millions in northern Europe would die over an extended number of years, marking a clear end to the earlier period of growth and prosperity during the 11th and 12th centuries. Starting with bad weather in the spring of 1315, universal crop failures lasted until the summer of 1317, from which Europe did not fully recover until 1322. It was a period marked by extreme levels of criminal activity, disease and mass death, infanticide, and cannibalism. It had consequences for Church, State, European society and future calamities to follow in the 14th century.
The 17th century was a period of change for the food producers of Europe. For centuries they had lived primarily as subsistence farmers in a feudal system. They had obligations to their lords, who had suzerainty over the land tilled by their peasants. The lord of a fief would take a portion of the crops and livestock produced during the year. Peasants generally tried to minimize the amount of work they had to put into agricultural food production. Their lords rarely pressured them to increase their food output, except when the population started to increase, at which time the peasants were likely to increase the production themselves. More land would be added to cultivation until there was no more available and the peasants were forced to take up more labour-intensive methods of production. Nonetheless, they generally tried to work as little as possible, valuing their time to do other things, such as hunting, fishing or relaxing, as long as they had enough food to feed their families. It was not in their interest to produce more than they could eat or store themselves.
During the 17th century, continuing the trend of previous centuries, there was an increase in market-driven agriculture. Farmers, people who rented land in order to make a profit off of the product of the land, employing wage labour, became increasingly common, particularly in western Europe. It was in their interest to produce as much as possible on their land in order to sell it to areas that demanded that product. They produced guaranteed surpluses of their crop every year if they could. Farmers paid their labourers in money, increasing the commercialization of rural society. This commercialization had a profound impact on the behaviour of peasants. Farmers were interested in increasing labour input into their lands, not decreasing it as subsistence peasants were.
Subsistence peasants were also increasingly forced to commercialize their activities because of increasing taxes. Taxes that had to be paid to central governments in money forced the peasants to produce crops to sell. Sometimes they produced industrial crops, but they would find ways to increase their production in order to meet both their subsistence requirements as well as their tax obligations. Peasants also used the new money to purchase manufactured goods. The agricultural and social developments encouraging increased food production were gradually taking place throughout the sixteenth century, but were spurred on more directly by the adverse conditions for food production that Europe found itself in the early seventeenth century — there was a general cooling trend in the Earth's temperature starting at the beginning end of the sixteenth century.
The 1590s saw the worst famines in centuries across all of Europe, except in certain areas, notably the Netherlands. Famine had been relatively rare during the 16th century. The economy and population had grown steadily as subsistence populations tend to when there is an extended period of relative peace (most of the time). Subsistence peasant populations will almost always increase when possible since the peasants will try to spread the work to as many hands as possible. Although peasants in areas of high population density, such as northern Italy, had learned to increase the yields of their lands through techniques such as promiscuous culture, they were still quite vulnerable to famines, forcing them to work their land even more intensively.
Famine is a very destabilizing and devastating occurrence. The prospect of starvation led people to take desperate measures. When scarcity of food became apparent to peasants, they would sacrifice long-term prosperity for short-term survival. They would kill their draught animals, leading to lowered production in subsequent years. They would eat their seed corn, sacrificing next year's crop in the hope that more seed could be found. Once those means had been exhausted, they would take to the road in search of food. They migrated to the cities where merchants from other areas would be more likely to sell their food, as cities had a stronger purchasing power than did rural areas. Cities also administered relief programs and bought grain for their populations so that they could keep order. With the confusion and desperation of the migrants, crime would often follow them. Many peasants resorted to banditry in order to acquire enough to eat.
One famine would often lead to difficulties in following years because of lack of seed stock or disruption of routine, or perhaps because of less-available labour. Famines were often interpreted as signs of God's displeasure. They were seen as the removal, by God, of His gifts to the people of the Earth. Elaborate religious processions and rituals were made to prevent God's wrath in the form of famine.
The great famine of the 1590s began the period of famine and decline in the 17th century. The price of grain, all over Europe was high, as was the population. Various types of people were vulnerable to the succession of bad harvests that occurred throughout the 1590s in different regions. The increasing number of wage labourers in the countryside were vulnerable because they had no food of their own, and their meager living was not enough to purchase the expensive grain of a bad-crop year. Town labourers were also at risk because their wages would be insufficient to cover the cost of grain, and, to make matters worse, they often received less money in bad-crop years since the disposable income of the wealthy was spent on grain. Often, unemployment would be the result of the increase in grain prices, leading to ever-increasing numbers of urban poor.
All areas of Europe were badly affected by the famine in these periods, especially rural areas. The Netherlands was able to escape most of the damaging effects of the famine, though the 1590s were still difficult years there. Actual famine did not occur, for the Amsterdam grain trade [with the Baltic] guaranteed that there would always be something to eat in the Netherlands although hunger was prevalent.
The Netherlands had the most commercialized agriculture in all of Europe at this time, growing many industrial crops, such as flax, hemp, and hops. Agriculture became increasingly specialized and efficient. As a result, productivity and wealth increased, allowing the Netherlands to maintain a steady food supply. By the 1620s, the economy was even more developed, so the country was able to avoid the hardships of that period of famine with even greater impunity.
The years around 1620 saw another period of famines sweep across Europe. These famines were generally less severe than the famines of twenty-five years earlier, but they were nonetheless quite serious in many areas. Perhaps the worst famine since 1600, the great famine in Finland in 1696, killed a third of the population. Template:PDFlink
The period of 1740–43 saw frigid winters and summer droughts which led to famine across Europe leading to a major spike in mortality.(cited in Davis, Late Victorian Holocausts, 281)
Other areas of Europe have known famines much more recently. France saw famines as recently as the nineteenth century. Famine still occurred in eastern Europe during the 20th century.
The frequency of famine can vary with climate changes. For example, during the little ice age of the 15th century to the 18th century, European famines grew more frequent than they had been during previous centuries.
Because of the frequency of famine in many societies, it has long been a chief concern of governments and other authorities. In pre-industrial Europe, preventing famine, and ensuring timely food supplies, was one of the chief concerns of many governments, which employed various tools to alleviate famines, including price controls, purchasing stockpiles of food from other areas, rationing, and regulation of production. Most governments were concerned by famine because it could lead to revolt and other forms of social disruption.
In contrast, the Great Irish Famine, 1845-1849, was in no small part the result of policies of the Whig government of the United Kingdom under Lord Russell. Unlike in Britain, the land in Ireland was owned mostly by Anglican people of English descent, who did not identify culturally or ethnically with their peasants. The landlords were known as the Anglo-Irish. As the landowners felt no compunction to use their political clout to aid their tenants, the British government's expedient response to the food crisis in Ireland was to leave the matter solely to market forces to decide. A strict free-market approach, aided by the British army guarding ports and food depots from the starving crowds, ensured food exports continued as before, and even increased during the famine period. The immediate effect was 1,000,000 dead and another 1,000,000 refugees fleeing to Britain and the United States. After the famine passed, infertility caused by famine, diseases and immigration spurred by the landlord-run economy being so thoroughly undermined, caused the population to enter into a 100-year decline. It was not until the 1970's that the population of Ireland, then at half of what it had been before the famine, began to rise again. This period of Irish population decline after the famine was at a time when the European population doubled and the English population increased fourfold. This left the country severely underpopulated. The population decline continued in parts of the country worst affected by the famine until the 1990s - 150 years after the famine and the British government's laissez-faire economic policy. Before the Hunger, Ireland's population was over half of England's. Today it is an eighth. The population of Ireland is 6 million but there are over 80 million more people of Irish descent outside of Ireland. That is 20 more times the population of Ireland.
Famine returned to the Netherlands during World War II in what was known as the Hongerwinter. It was the last famine of Europe, in which approximately 30,000 people died of starvation. Some other areas of Europe also experienced famine at the same time.
The harvest failures were devastating for the northern Italian economy. The economy of the area had recovered well from the previous famines, but the famines from 1618 to 1621 coincided because of a period of war in the area. The economy did not recover fully for centuries. There were serious famines in the late-1640s and less severe ones in the 1670s throughout northern Italy.
From 1536 England began legislating Poor Laws which put a legal responsibility on the rich, at a parish level, to maintain the poor of that parish. English agriculture lagged behind the Netherlands, but by 1650 their agricultural industry was commercialized on a wide scale. The last peace-time famine in England was in 1623–24. There were still periods of hunger, as in the Netherlands, but there were no more famines as such. Rising population levels continued to put a strain on food security, despite potatoes becoming increasingly important in the diet of the poor. On balance, potatoes increased food security in England where they never replaced bread as the staple of the poor. Climate conditions were never likely to simultaneously be catastrophic for both the wheat and potato crops.
In 1783 the volcano Laki in south-central Iceland erupted. The lava caused little direct damage, but ash and sulfur dioxide spewed out over most of the country, causing three-quarters of the island's livestock to perish. In the following famine, around ten thousand people died, one-fifth of the population of Iceland. [Asimov, 1984, 152-153]
### Russia and the USSR
Droughts and famines in Imperial Russia are known to have happened every 10 to 13 years, with average droughts happening every 5 to 7 years. Famines continued in the Soviet era, the most famous one being the Holodomor in Ukraine (1932–1933). The last major famine in the USSR happened in 1947 due to the severe drought.
# Notes
- ↑ Poor studies will always be with us
- ↑ The facts on malnutrition & famine
- ↑ Rising food prices curb aid to global poor
- ↑ The limits of a Green Revolution?
- ↑ How Much Did the Green Revolution Matter?
- ↑ Eating Fossil Fuels | EnergyBulletin.net
- ↑ Peak Oil: the threat to our food security
- ↑ Agriculture Meets Peak Oil
- ↑ Len Milich: Anthropogenic Desertification vs ‘Natural’ Climate Trends
- ↑ El Niño and Drought Early Warning in Ethiopia
- ↑ See, for example, Andrey Korotayev and Daria Khaltourina Secular Cycles and Millennial Trends in Africa. Moscow: Russia, 2006.
- ↑ Africa may be able to feed only 25% of its population by 2025
- ↑ China: Land of Famine
- ↑ Fearfull Famines of the Past
- ↑ Famine - Encyclopaedia Britannica 1911
- ↑ http://www.lrb.co.uk/v27/n24/cumi01_.html | https://www.wikidoc.org/index.php/Famine | |
f8874904c75e954d47aacc0fa1833181ef5eae8d | wikidoc | Fascin | Fascin
Fascin is an actin bundling protein.
# Species and tissue distribution
It is a 54-58 kilodalton monomeric actin filament bundling protein originally isolated from sea urchin egg but also found in Drosophila and vertebrates, including humans. Fascin (from the Latin for bundle) is spaced at 11 nanometre intervals along the filament. The bundles in cross section are seen to be hexagonally packed, and the longitudinal spacing is compatible with a model where fascin cross-links at alternating 4 and 5 actins. It is calcium insensitive and monomeric. Three forms of fascin are found in vertebrates: Fascin1, widely found in the nervous system and elsewhere; fascin2 found in the retinal photoreceptor cells; fascin3, which is only found in the testes.
# Function
Fascin binds beta-catenin, and colocalizes with it at the leading edges and borders of epithelial and endothelial cells. The role of Fascin in regulating cytoskeletal structures for the maintenance of cell adhesion, coordinating motility and invasion through interactions with signalling pathways is an active area of research especially from the cancer biology perspective. Fascin localizes to actin-rich protrusions at the cell surface called filopodia. Recent study shows that fascin also localizes to invadopodia, membrane protrusions formed at the adherent cell surface that facilitate extracellular matrix (ECM) invasion, this provide a potential molecular mechanism for how fascin increases the invasiveness of cancer cells since fascin expression is upregulated in a spectrum of cancers. Studies have also shown that Fascin plays a major role in immune suppression. T regulatory cell adhesion to antigen presenting dendritic cell causes sequestration of Fascin-1, an actin-bundling protein essential for immunological synapse formation, and skews Fascin-1–dependent actin polarization in antigen presenting dendritic cells toward the T reg cell adhesion zone. Although it is reversible upon T regulatory cell disengagement, this sequestration of essential cytoskeletal components causes a lethargic state of dendritic cells, leading to reduced T cell priming. This suggests Treg-mediated suppression of antigen presenting cells is a multi-step process. In addition to CTLA-4 CD80/CD86 interaction fascin dependent polarization of cytoskeleton towards dendritic cell Treg immune synapse play a pivotal role. In normal tissue, inflammation and the immune response would be limited by secretion of TGF-β. TGF-β on the one hand induces fascin expression, but on the other hand, restricts activity of transcription factor NF-κB. This results to limited fascin expression and allows tissue to rebuild epithelial barriers. In cancer, instead, TGF-β does not restrict NF-κB activity, and both can increase fascin expression, disrupting tissue structure and function.
# Clinical significance
Abnormal fascin expression or function has been implicated in breast cancer, colon cancer, esophageal squamous cell carcinoma, gallbladder cancer, pancreatic cancer, and prostate cancer. It is also helpful in identifying Hodgkin cells.
# Structure
Fascin is a structural protein found in mesenchyme, nervous, and retinal tissue and is used in the bundling of actin molecules.
The structure of human fascin has been determined to a resolution of 1.8 Å (PDBID 3LLP) and reveals an arrangement of four tandem beta-trefoil domains that form a two lobed structure with pseudo 2-fold symmetry. It is stabilized by a hydrophobic core and a hydrophilic surface since it is often found inside cell cytoplasm in the formation of filopodia. | Fascin
Fascin is an actin bundling protein.
# Species and tissue distribution
It is a 54-58 kilodalton monomeric actin filament bundling protein originally isolated from sea urchin egg but also found in Drosophila[2] and vertebrates,[3] including humans.[4] Fascin (from the Latin for bundle) is spaced at 11 nanometre intervals along the filament. The bundles in cross section are seen to be hexagonally packed, and the longitudinal spacing is compatible with a model where fascin cross-links at alternating 4 and 5 actins.[5] It is calcium insensitive and monomeric. Three forms of fascin are found in vertebrates: Fascin1, widely found in the nervous system and elsewhere; fascin2 found in the retinal photoreceptor cells; fascin3, which is only found in the testes.[6][7]
# Function
Fascin binds beta-catenin,[8] and colocalizes with it at the leading edges and borders of epithelial and endothelial cells. The role of Fascin in regulating cytoskeletal structures for the maintenance of cell adhesion, coordinating motility and invasion through interactions with signalling pathways is an active area of research especially from the cancer biology perspective.[6][7] Fascin localizes to actin-rich protrusions at the cell surface called filopodia. Recent study shows that fascin also localizes to invadopodia, membrane protrusions formed at the adherent cell surface that facilitate extracellular matrix (ECM) invasion, this provide a potential molecular mechanism for how fascin increases the invasiveness of cancer cells since fascin expression is upregulated in a spectrum of cancers.[9] Studies have also shown that Fascin plays a major role in immune suppression. T regulatory cell adhesion to antigen presenting dendritic cell causes sequestration of Fascin-1, an actin-bundling protein essential for immunological synapse formation, and skews Fascin-1–dependent actin polarization in antigen presenting dendritic cells toward the T reg cell adhesion zone. Although it is reversible upon T regulatory cell disengagement, this sequestration of essential cytoskeletal components causes a lethargic state of dendritic cells, leading to reduced T cell priming. This suggests Treg-mediated suppression of antigen presenting cells is a multi-step process. In addition to CTLA-4 CD80/CD86 interaction fascin dependent polarization of cytoskeleton towards dendritic cell Treg immune synapse play a pivotal role.[10] In normal tissue, inflammation and the immune response would be limited by secretion of TGF-β. TGF-β on the one hand induces fascin expression, but on the other hand, restricts activity of transcription factor NF-κB. This results to limited fascin expression and allows tissue to rebuild epithelial barriers. In cancer, instead, TGF-β does not restrict NF-κB activity, and both can increase fascin expression, disrupting tissue structure and function. [11]
# Clinical significance
Abnormal fascin expression or function has been implicated in breast cancer,[12] colon cancer,[13][14] esophageal squamous cell carcinoma,[15] gallbladder cancer,[16] pancreatic cancer,[17] and prostate cancer.[18] It is also helpful in identifying Hodgkin cells.
# Structure
Fascin is a structural protein found in mesenchyme, nervous, and retinal tissue and is used in the bundling of actin molecules.[19]
The structure of human fascin has been determined to a resolution of 1.8 Å (PDBID 3LLP) and reveals an arrangement of four tandem beta-trefoil domains that form a two lobed structure with pseudo 2-fold symmetry. It is stabilized by a hydrophobic core and a hydrophilic surface since it is often found inside cell cytoplasm in the formation of filopodia.[1] | https://www.wikidoc.org/index.php/Fascin | |
38730d7e087ae26427d4bcda50caf8b71f7aed7a | wikidoc | Female | Female
Female (♀) is the sex of an organism, or a part of an organism, which produces ova (egg cells). The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon is produced by the male. A female individual cannot reproduce sexually without access to the gametes of a male (an exception is parthenogenesis). Some organisms can reproduce both sexually and asexually.
There is no single genetic mechanism behind sex differences in different species and the existence of two sexes seems to have evolved multiple times independently in different evolutionary lineages. Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. The concept is not limited to animals; egg cells are produced by chytrids, diatoms, water molds and land plants, among others. In land plants, female and male designate not only the egg- and sperm-producing organisms and structures, but also the structures of the sporophytes that give rise to male and female plants.
# Sex determination
The sex of a particular organism may be determined by a number of factors. These may be genetic or environmental, or may naturally change during the course of an organism's life. Although most species with male and female sexes have individuals that are either male or female, hermaphroditic animals have both male and female reproductive organs.
## Genetic determination
Most mammals, including humans, are genetically determined as such by the XY sex-determination system where males have an XY (as opposed to XX) sex chromosome. During reproduction, a male can give either an X sperm or a Y sperm, while a female can only give an X egg. A Y sperm and an X egg produce a boy, while an X sperm and an X egg produce a girl. The ZW sex-determination system, where males have a ZZ (as opposed to ZW) sex chromosome may be found in birds and some insects and other organisms. Members of Hymenoptera, such as ants and bees, are determined by haplodiploidy, where most males are haploid and females and some sterile males are diploid.
## Environmental determination
In some species of reptiles, including alligators, sex is determined by the temperature at which the egg is incubated. Other species, such as some snails, practice sex change: adults start out male, then become female. In tropical clown fish, the dominant individual in a group becomes female while the other ones are male.
In some arthropods, sex is determined by infection. Their sex is altered by bacteria of the genus Wolbachia; some species consist entirely of ZZ individuals, with sex determined by the presence of Wolbachia.
# Mammalian female
The mammalian female is characterised by having two copies of the X chromosome as opposed to the male which carries only one X and one smaller Y chromosome. To compensate for the difference in size, one of the female's X chromosomes is randomly inactivated in each cell.
Conversely in birds it is the female who is heterozygote and carries a Z and a W chromosome whilst the male carries two Z chromosomes.
The distinguishing characteristic of mammalian species is the presence of mammary glands on the female. The mammary glands are modified sweat glands that produce milk, which is used to feed the young during the period of time shortly after birth. Only mammals have the capacity to produce milk. The presence of mammary glands is most obvious on humans, due to the tendency of the female human body to store large amounts of fatty tissue near the nipples, resulting in prominent breasts. However, mammary glands are present in all mammals, although they are vestigial in male organisms.
Mammalian females are also unique in that they all bear live young (with the exception of monotremes, which lay eggs.) However, there are non-mammalian animals (such as sharks) whose eggs hatch inside their bodies, which gives the appearance that they bear live young.
# Symbols
A common symbol used to represent the female gender is ♀ (Unicode: U+2640 Alt codes: Alt+12), a circle with a small cross underneath. This symbol also represents the planet Venus and is a stylized representation of the goddess Venus' hand mirror.
# Etymology and Usage
The word female comes from the Latin femella, the diminuative form of femina, meaning 'woman', which is not actually related to the word 'male.' The word was probably originally femella, meaning "young girl". In the late 14th century, the English spelling was altered so that the word paralleled the spelling of "male".
The word female is generally considered neutral when used as an adjective; when used as a noun, it is often regarded as derogatory.
Female judge would be preferable to woman judge; "This judge is a woman" would be preferable to "This judge is a female."
There are exceptions: League of Women Voters is a name chosen by the mostly-female members of the League. The American Heritage Dictionary and the Random House Dictionary are not completely clear on this point, which is a sensitive point: it is hard to find neutral terms for women performing jobs once reserved for men, because these women generally insist that they belong there; and many other people—including some women—insist that they do not.
The phrase the female, in the sense of the female sex or the class of all wowen, figures prominently in the first act of Henry V, in which Henry's bishops discuss with him the right of the French King to his throne—and Henry's right to usurp it. They conclude that the salic law cited by the French is not really French, but German, and that Henry can properly invade France, thus prolonging the Hundred Years' War.
# Sources
Ayers, Donald M. English Words from Latin and Greek Elements. Second Edition. 1986. University of Arizona Press. United States. | Female
Female (♀) is the sex of an organism, or a part of an organism, which produces ova (egg cells). The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon is produced by the male. A female individual cannot reproduce sexually without access to the gametes of a male (an exception is parthenogenesis). Some organisms can reproduce both sexually and asexually.
There is no single genetic mechanism behind sex differences in different species and the existence of two sexes seems to have evolved multiple times independently in different evolutionary lineages. Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. The concept is not limited to animals; egg cells are produced by chytrids, diatoms, water molds and land plants, among others. In land plants, female and male designate not only the egg- and sperm-producing organisms and structures, but also the structures of the sporophytes that give rise to male and female plants.
# Sex determination
The sex of a particular organism may be determined by a number of factors. These may be genetic or environmental, or may naturally change during the course of an organism's life. Although most species with male and female sexes have individuals that are either male or female, hermaphroditic animals have both male and female reproductive organs.
## Genetic determination
Most mammals, including humans, are genetically determined as such by the XY sex-determination system where males have an XY (as opposed to XX) sex chromosome. During reproduction, a male can give either an X sperm or a Y sperm, while a female can only give an X egg. A Y sperm and an X egg produce a boy, while an X sperm and an X egg produce a girl. The ZW sex-determination system, where males have a ZZ (as opposed to ZW) sex chromosome may be found in birds and some insects and other organisms. Members of Hymenoptera, such as ants and bees, are determined by haplodiploidy, where most males are haploid and females and some sterile males are diploid.
## Environmental determination
In some species of reptiles, including alligators, sex is determined by the temperature at which the egg is incubated. Other species, such as some snails, practice sex change: adults start out male, then become female. In tropical clown fish, the dominant individual in a group becomes female while the other ones are male.
In some arthropods, sex is determined by infection. Their sex is altered by bacteria of the genus Wolbachia; some species consist entirely of ZZ individuals, with sex determined by the presence of Wolbachia.
# Mammalian female
The mammalian female is characterised by having two copies of the X chromosome as opposed to the male which carries only one X and one smaller Y chromosome. To compensate for the difference in size, one of the female's X chromosomes is randomly inactivated in each cell.
Conversely in birds it is the female who is heterozygote and carries a Z and a W chromosome whilst the male carries two Z chromosomes.
The distinguishing characteristic of mammalian species is the presence of mammary glands on the female. The mammary glands are modified sweat glands that produce milk, which is used to feed the young during the period of time shortly after birth. Only mammals have the capacity to produce milk. The presence of mammary glands is most obvious on humans, due to the tendency of the female human body to store large amounts of fatty tissue near the nipples, resulting in prominent breasts. However, mammary glands are present in all mammals, although they are vestigial in male organisms.
Mammalian females are also unique in that they all bear live young (with the exception of monotremes, which lay eggs.) However, there are non-mammalian animals (such as sharks) whose eggs hatch inside their bodies, which gives the appearance that they bear live young.
# Symbols
A common symbol used to represent the female gender is ♀ (Unicode: U+2640 Alt codes: Alt+12), a circle with a small cross underneath. This symbol also represents the planet Venus and is a stylized representation of the goddess Venus' hand mirror.
# Etymology and Usage
The word female comes from the Latin femella, the diminuative form of femina, meaning 'woman', which is not actually related to the word 'male.' The word was probably originally femella, meaning "young girl". In the late 14th century, the English spelling was altered so that the word paralleled the spelling of "male".
The word female is generally considered neutral when used as an adjective; when used as a noun, it is often regarded as derogatory.
Female judge would be preferable to woman judge; "This judge is a woman" would be preferable to "This judge is a female."
There are exceptions: League of Women Voters is a name chosen by the mostly-female members of the League. The American Heritage Dictionary and the Random House Dictionary are not completely clear on this point, which is a sensitive point: it is hard to find neutral terms for women performing jobs once reserved for men, because these women generally insist that they belong there; and many other people—including some women—insist that they do not.
The phrase the female, in the sense of the female sex or the class of all wowen, figures prominently in the first act of Henry V, in which Henry's bishops discuss with him the right of the French King to his throne—and Henry's right to usurp it. They conclude that the salic law cited by the French is not really French, but German, and that Henry can properly invade France, thus prolonging the Hundred Years' War.
# Sources
Ayers, Donald M. English Words from Latin and Greek Elements. Second Edition. 1986. University of Arizona Press. United States. | https://www.wikidoc.org/index.php/Female | |
f06443c0e7a102f045f249c79eed23398e056ecc | wikidoc | Second | Second
The second (SI symbol: s), sometimes abbreviated sec., is the name of a unit of time, and is the International System of Units (SI) base unit of time.
SI prefixes are frequently combined with the word second to denote subdivisions of the second, e.g., the millisecond (one thousandth of a second) and nanosecond (one billionth of a second). Though SI prefixes may also be used to form multiples of the second (such as “kilosecond,” or one thousand seconds), such units are rarely used in practice. More commonly encountered, non-SI units of time such as the minute, hour, and day increase by multiples of 60 and 24 (rather than by powers of ten as in the SI system).
# International second
Under the International System of Units, the second is currently defined as
This definition refers to a caesium atom at rest at a temperature of 0 K (absolute zero). The ground state is defined at zero magnetic field. The second thus defined is equivalent to the ephemeris second, which was based on astronomical measurements. (See History below.)
The international standard symbol for a second is s (see ISO 31-1)
The realization of the standard second is described briefly in NIST Special Publication 330; Appendix 2, pp. 53 ff, and in detail by National Research Council of Canada.
# Equivalence to other units of time
1 international second is equal to:
- 1/60 minute
- 1/3,600 hour
- 1/86,400 day (IAU system of units)
- 1/31,557,600 Julian year (IAU system of units)
# History
The Egyptians had subdivided daytime and nighttime into twelve hours each since at least 2000 BC, hence their hours varied seasonally. The Hellenistic astronomers Hipparchus (c. 150 BC) and Ptolemy (c. AD 150) subdivided the day sexagesimally and also used a mean hour (1⁄24 day), but did not use distinctly named smaller units of time. Instead they used simple fractions of an hour.
The day was subdivided sexagesimally, that is by 1⁄60, by 1⁄60 of that, by 1⁄60 of that, etc., to at least six places after the sexagesimal point by the Babylonians after 300 BC, but they did not sexagesimally subdivide smaller units of time. For example, six fractional sexagesimal places of a day was used in their specification of the length of the year, although they were unable to measure such a small fraction of a day in real time. As another example, they specified that the mean synodic month was 29;31,50,8,20 days (four fractional sexagesimal positions), which was repeated by Hipparchus and Ptolemy sexagesimally, and is currently the mean synodic month of the Hebrew calendar, though restated as 29 days 12 hours 793 halakim (where 1 hour = 1080 halakim). They did not use the hour, but did use a double-hour, a time-degree lasting four of our minutes, and a barleycorn lasting 3⅓ of our seconds (the helek of the modern Hebrew calendar).
In 1000, the Muslim scholar al-Biruni gave the times of the new moons of specific weeks as a number of days, hours, minutes, seconds, thirds, and fourths after noon Sunday. In 1267, the medieval scientist Roger Bacon stated the times of full moons as a number of hours, minutes, seconds, thirds, and fourths (horae, minuta, secunda, tertia, and quarta) after noon on specified calendar dates. Although a third for 1⁄60 of a second remains in some languages, for example Polish (tercja) and Arabic (ثالثة), the modern second is subdivided decimally.
The second first became measurable with the development of pendulum clocks keeping mean time (as opposed to the apparent time displayed by sundials), specifically in 1670 when William Clement added a seconds pendulum to the original pendulum clock of Christian Huygens. The seconds pendulum has a period of two seconds, one second for a swing forward and one second for a swing back, enabling the longcase clock incorporating it to tick seconds. From this time, a second hand that rotated once per minute in a small subdial began to be added to the clock faces of precision clocks.
In 1956 the second was defined in terms of the period of revolution of the Earth around the Sun for a particular epoch, because by then it had become recognized that the Earth's rotation on its own axis was not sufficiently uniform as a standard of time. The Earth's motion was described in Newcomb's Tables of the Sun, which provides a formula for the motion of the Sun at the epoch 1900 based on astronomical observations made between 1750 and 1892. The second thus defined is
This definition was ratified by the Eleventh General Conference on Weights and Measures in 1960. The tropical year in the definition was not measured, but calculated from a formula describing a mean tropical year which decreased linearly over time, hence the curious reference to a specific instantaneous tropical year. Because this second was the independent variable of time used in ephemerides of the Sun and Moon during most of the twentieth century (Newcomb's Tables of the Sun were used from 1900 through 1983, and Brown's Tables of the Moon were used from 1920 through 1983), it was called the ephemeris second.
With the development of the atomic clock, it was decided to use atomic clocks as the basis of the definition of the second, rather than the revolution of the Earth around the Sun.
Following several years of work, Louis Essen from the National Physical Laboratory (Teddington, England) and William Markowitz from the United States Naval Observatory (USNO) determined the relationship between the hyperfine transition frequency of the caesium atom and the ephemeris second. Using a common-view measurement method based on the received signals from radio station WWV, they determined the orbital motion of the Moon about the Earth, from which the apparent motion of the Sun could be inferred, in terms of time as measured by an atomic clock. As a result, in 1967 the Thirteenth General Conference on Weights and Measures defined the second of atomic time in the International System of Units as
During the 1970s it was realized that gravitational time dilation caused the second produced by each atomic clock to differ depending on its altitude. A uniform second was produced by correcting the output of each atomic clock to mean sea level (the rotating geoid), lengthening the second by about 1Template:E. This correction was applied at the beginning of 1977 and formalized in 1980. In relativistic terms, the SI second is defined as the proper time on the rotating geoid.
The definition of the second was later refined at the 1997 meeting of the BIPM to include the statement
The revised definition would seem to imply that the ideal atomic clock would contain a single caesium atom at rest emitting a single frequency. In practice, however, the definition means that high-precision realizations of the second should compensate for the effects of the ambient temperature (black-body radiation) within which atomic clocks operate and extrapolate accordingly to the value of the second as defined above.
For approximately twenty years, it has been possible to confine an ion to a region of space smaller than one cubic micron (10-6 m)3. Such an ion is almost completely isolated from the surrounding environment and suggests a frequency or time standard with a reproducibility and stability several orders of magnitude superior to the best caesium time standards. Such standards are under development. See magneto-optical trap and "Trapped ion optical frequency standards". National Physical Laboratory..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
# Approximations
It is a common belief that saying one one thousand, two one thousand three one thousand...... can be used to time events in seconds (one mississippi, two mississippi is another common sequence)
# SI multiples
SI prefixes are commonly used to measure time less than a second, but rarely for multiples of a second, instead the non-SI units minutes, hours and days are used. | Second
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
The second (SI symbol: s), sometimes abbreviated sec., is the name of a unit of time, and is the International System of Units (SI) base unit of time.
SI prefixes are frequently combined with the word second to denote subdivisions of the second, e.g., the millisecond (one thousandth of a second) and nanosecond (one billionth of a second). Though SI prefixes may also be used to form multiples of the second (such as “kilosecond,” or one thousand seconds), such units are rarely used in practice. More commonly encountered, non-SI units of time such as the minute, hour, and day increase by multiples of 60 and 24 (rather than by powers of ten as in the SI system).
# International second
Under the International System of Units, the second is currently defined as
This definition refers to a caesium atom at rest at a temperature of 0 K (absolute zero). The ground state is defined at zero magnetic field. The second thus defined is equivalent to the ephemeris second, which was based on astronomical measurements. (See History below.)
The international standard symbol for a second is s[2] (see ISO 31-1)
The realization of the standard second is described briefly in NIST Special Publication 330; Appendix 2, pp. 53 ff, and in detail by National Research Council of Canada.
# Equivalence to other units of time
1 international second is equal to:
- 1/60 minute
- 1/3,600 hour
- 1/86,400 day (IAU system of units)
- 1/31,557,600 Julian year (IAU system of units)
# History
The Egyptians had subdivided daytime and nighttime into twelve hours each since at least 2000 BC, hence their hours varied seasonally. The Hellenistic astronomers Hipparchus (c. 150 BC) and Ptolemy (c. AD 150) subdivided the day sexagesimally and also used a mean hour (1⁄24 day), but did not use distinctly named smaller units of time. Instead they used simple fractions of an hour.
The day was subdivided sexagesimally, that is by 1⁄60, by 1⁄60 of that, by 1⁄60 of that, etc., to at least six places after the sexagesimal point by the Babylonians after 300 BC, but they did not sexagesimally subdivide smaller units of time. For example, six fractional sexagesimal places of a day was used in their specification of the length of the year, although they were unable to measure such a small fraction of a day in real time. As another example, they specified that the mean synodic month was 29;31,50,8,20 days (four fractional sexagesimal positions), which was repeated by Hipparchus and Ptolemy sexagesimally, and is currently the mean synodic month of the Hebrew calendar, though restated as 29 days 12 hours 793 halakim (where 1 hour = 1080 halakim).[3] They did not use the hour, but did use a double-hour, a time-degree lasting four of our minutes, and a barleycorn lasting 3⅓ of our seconds (the helek of the modern Hebrew calendar).[4]
In 1000, the Muslim scholar al-Biruni gave the times of the new moons of specific weeks as a number of days, hours, minutes, seconds, thirds, and fourths after noon Sunday.[5] In 1267, the medieval scientist Roger Bacon stated the times of full moons as a number of hours, minutes, seconds, thirds, and fourths (horae, minuta, secunda, tertia, and quarta) after noon on specified calendar dates.[6] Although a third for 1⁄60 of a second remains in some languages, for example Polish (tercja) and Arabic (ثالثة), the modern second is subdivided decimally.
The second first became measurable with the development of pendulum clocks keeping mean time (as opposed to the apparent time displayed by sundials), specifically in 1670 when William Clement added a seconds pendulum to the original pendulum clock of Christian Huygens.[7] The seconds pendulum has a period of two seconds, one second for a swing forward and one second for a swing back, enabling the longcase clock incorporating it to tick seconds. From this time, a second hand that rotated once per minute in a small subdial began to be added to the clock faces of precision clocks.
In 1956 the second was defined in terms of the period of revolution of the Earth around the Sun for a particular epoch, because by then it had become recognized that the Earth's rotation on its own axis was not sufficiently uniform as a standard of time. The Earth's motion was described in Newcomb's Tables of the Sun, which provides a formula for the motion of the Sun at the epoch 1900 based on astronomical observations made between 1750 and 1892.[8] The second thus defined is
This definition was ratified by the Eleventh General Conference on Weights and Measures in 1960. The tropical year in the definition was not measured, but calculated from a formula describing a mean tropical year which decreased linearly over time, hence the curious reference to a specific instantaneous tropical year. Because this second was the independent variable of time used in ephemerides of the Sun and Moon during most of the twentieth century (Newcomb's Tables of the Sun were used from 1900 through 1983, and Brown's Tables of the Moon were used from 1920 through 1983), it was called the ephemeris second.[8]
With the development of the atomic clock, it was decided to use atomic clocks as the basis of the definition of the second, rather than the revolution of the Earth around the Sun.
Following several years of work, Louis Essen from the National Physical Laboratory (Teddington, England) and William Markowitz from the United States Naval Observatory (USNO) determined the relationship between the hyperfine transition frequency of the caesium atom and the ephemeris second.[8] Using a common-view measurement method based on the received signals from radio station WWV,[9] they determined the orbital motion of the Moon about the Earth, from which the apparent motion of the Sun could be inferred, in terms of time as measured by an atomic clock. As a result, in 1967 the Thirteenth General Conference on Weights and Measures defined the second of atomic time in the International System of Units as
During the 1970s it was realized that gravitational time dilation caused the second produced by each atomic clock to differ depending on its altitude. A uniform second was produced by correcting the output of each atomic clock to mean sea level (the rotating geoid), lengthening the second by about 1Template:E. This correction was applied at the beginning of 1977 and formalized in 1980. In relativistic terms, the SI second is defined as the proper time on the rotating geoid.[10]
The definition of the second was later refined at the 1997 meeting of the BIPM to include the statement
The revised definition would seem to imply that the ideal atomic clock would contain a single caesium atom at rest emitting a single frequency. In practice, however, the definition means that high-precision realizations of the second should compensate for the effects of the ambient temperature (black-body radiation) within which atomic clocks operate and extrapolate accordingly to the value of the second as defined above.
For approximately twenty years, it has been possible to confine an ion to a region of space smaller than one cubic micron (10-6 m)3. Such an ion is almost completely isolated from the surrounding environment and suggests a frequency or time standard with a reproducibility and stability several orders of magnitude superior to the best caesium time standards. Such standards are under development. See magneto-optical trap and "Trapped ion optical frequency standards". National Physical Laboratory..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
# Approximations
It is a common belief that saying one one thousand, two one thousand three one thousand...... can be used to time events in seconds (one mississippi, two mississippi is another common sequence)
# SI multiples
SI prefixes are commonly used to measure time less than a second, but rarely for multiples of a second, instead the non-SI units minutes, hours and days are used.
Template:SI multiples | https://www.wikidoc.org/index.php/Femtosecond | |
d3d9b42fd7d89542b133ee3b4c8d962f458e9754 | wikidoc | Fennel | Fennel
Fennel (Foeniculum vulgare) is a plant species in the genus Foeniculum (treated as the sole species in the genus by most botanists). It is a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves, grows wild in most parts of temperate Europe, but is generally considered indigenous to the shores of the Mediterranean, whence it spreads eastwards to India. It has followed civilization, especially where Romans have colonized, and may be found growing wild in many parts of the world upon dry soils near the sea-coast and upon river-banks. It is a member of the family Apiaceae. It is a highly aromatic and flavorful herb with culinary and medicinal uses, and is one of the primary ingredients of absinthe. Fennel is used as a food plant by the larvae of some Lepidoptera species including the Mouse Moth and the Anise Swallowtail.
# Appearance
Fennel is a perennial herb, meaning that it grows year-round. It is erect, glaucous green, and grows to heights of up to 2.5 m, with hollow stems. The leaves grow up to 40 cm long; they are finely dissected, with the ultimate segments filiform, about 0.5 mm wide. Its leaves are similar to those of dill, but thinner. The flowers are produced in terminal compound umbels 5–15 cm wide, each umbel section having 20–50 tiny yellow flowers on short pedicels. The fruit is a dry seed from 4–10 mm long, half as wide or less, and grooved.
# Cultivation and uses
Fennel is widely cultivated, both in its native range and elsewhere, for its edible, strongly-flavoured leaves and seeds. The flavour is similar to that of anise and star anise, though usually not as strong.
The Florence fennel (Foeniculum vulgare Azoricum Group; syn. F. vulgare var. azoricum) is a Cultivar Group with inflated leaf bases which form a bulb-like structure. It is of cultivated origin, and has a mild anise-like flavour, but is more aromatic and sweeter. Its flavour comes from anethole, an aromatic compound also found in anise and star anise. Florence fennel plants are smaller than the wild type and have inflated leaf bases which are eaten as a vegetable, both raw and cooked. There are several cultivars of Florence fennel, which is also known by several other names, notably the Italian name finocchio. In North American supermarkets, it is often mislabelled as "anise".
Fennel has become naturalised along roadsides, in pastures, and in other open sites in many regions, including northern Europe, the United States, southern Canada and in much of Asia and Australia. It propagates well by seed, and is considered an invasive species and a weed in Australia and the United States (see Santa Cruz Island).
Florence fennel was one of the three main herbs used in the preparation of absinthe, an alcoholic mixture which originated as a medicinal elixir in Switzerland and became, by the late 19th century, a popular alcoholic drink in France and other countries. Due to the belief that absinthe possessed psychoactive properties beyond those of alcohol, it was banned in most countries by 1915, but a recent relaxation of laws governing its production, importation and sale has caused a moderate resurgence in modern day consumption. Fennel itself is known to be a stimulant, although many modern preparations marketed under the name "absinthe" do not make use of it.
## Culinary uses
The bulb, foliage, and seeds of the fennel plant are widely used in many of the culinary traditions of the world. Fennel pollen is the most potent form of fennel, but also the most expensive. Dried fennel seed is an aromatic, anise-flavoured spice, brown or green in colour when fresh, slowly turning a dull grey as the seed ages. For cooking, green seeds are optimal. The leaves are delicately flavored and similar in shape to those of dill. The bulb is a crisp, hardy root vegetable and may be sauteed, stewed, braised, grilled, or eaten raw.
Fennel seeds are sometimes confused with those of anise, which are very similar in taste and appearance, though smaller. In India, it is common to chew fennel seed (or saunf) as a mouth-freshener. Fennel is also used as a flavouring in some natural toothpaste. Some people employ it as a diuretic. Others use it to improve the milk supply of breastfeeding mothers, but it has shown neurotoxicity in certain cases where the mother ingested it as an herbal tea to enhance her breast milk.
Fennel is most prominently featured in Italian cuisine, where bulbs and fronds appears both raw and cooked in side dishes, salads, pastas, and risottos. Fennel seed is a common ingredient in Italian sausages and meatballs and northern European rye breads.
Many cultures in the Indian subcontinent and the Middle East incorporate fennel seed into their culinary traditions. It is an essential ingredient in the Bengali/Oriya spice mixture panch phoron and in Chinese five-spice powders. It is known as saunf or mauti saunf in Hindi and Urdu, mouri in Bengali, shombu or peruncheeragam in Tamil language, variyali in Gujarati, and barishap in the Malay language.
Many egg, fish, and other dishes employ fresh or dried fennel leaves. Florence fennel is a key ingredient in some Italian and German salads, often tossed with chicory and avocado, or it can be braised and served as a warm side dish. It may be blanched or marinated, or cooked in risotto. In all cases, the leaves lend their characteristically mild, anise-like flavour.
## Medicinal uses
Fennel contains anethole, which can explain some of its effects: it, or its polymers, act as phytoestrogens. On account of its aromatic and carminative properties, Fennel is chiefly used medicinally with purgatives to allay their side effects and for this purpose forms one of the ingredients of the well-known compound Liquorice Powder. Fennel water has properties similar to those of anise and dill water: mixed with sodium bicarbonate and syrup, these waters constitute the domestic 'Gripe Water,' used to correct the flatulence of infants. Essential oil of Fennel has these properties in concentration. Fennel tea, formerly also employed as a carminative, is made by pouring boiling water on a teaspoonful of bruised Fennel seeds. Syrup prepared from Fennel juice was formerly given for chronic coughs. Fennel is also largely used for cattle condiments. It is one of the plants which is said to be disliked by fleas, and powdered Fennel has the effect of driving away fleas from kennels and stables.
# Etymology and history
The word fennel developed from the Middle English fenel or fenyl, which came from the Anglo-Saxon fenol or finol, which in turn came from the Latin feniculum or foeniculum, the diminutive of fenum or faenum, meaning "hay". The Latin word for the plant was ferula, which is now used as the genus name of a related plant.
In Ancient Greek, fennel was called marathon (μάραθον), and is attested in Linear B tablets as ma-ra-tu-wo. John Chadwick notes that this word is the origin of the place name Marathon (meaning "place of fennel"), site of the Battle of Marathon in 490 BC; however, Chadwick wryly notes that he has "not seen any fennel growing there now". In Greek mythology, Prometheus used the stalk of a fennel plant to steal fire from the gods. Also, it was from the giant fennel, Ferula communis, that the Bacchanalian wands of the god Dionysus and his followers were said to have come.
In medieval times fennel was used in conjunction with St John's wort to keep away witchcraft and other evil things. This practice may have originated from fennel's use as an insect repellent.
Fennel is thought to be one of the nine herbs held sacred by the Anglo-Saxons. (The other eight are not entirely certain, but were probably mugwort (Artemisia vulgaris), greater plantain (Plantago major), watercress (Nasturtium officinale), wild chamomile (Matricaria recutita), stinging nettle (Urtica dioica), crab apple (Malus sylvestris), chervil (Anthriscus cerefolium), and viper's bugloss (Echium vulgare).)
# Production
India is leader in production of Fennel followed by Syrian Arab Republic. | Fennel
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Fennel (Foeniculum vulgare) is a plant species in the genus Foeniculum (treated as the sole species in the genus by most botanists). It is a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves, grows wild in most parts of temperate Europe, but is generally considered indigenous to the shores of the Mediterranean, whence it spreads eastwards to India. It has followed civilization, especially where Romans have colonized, and may be found growing wild in many parts of the world upon dry soils near the sea-coast and upon river-banks.[1] It is a member of the family Apiaceae. It is a highly aromatic and flavorful herb with culinary and medicinal uses, and is one of the primary ingredients of absinthe. Fennel is used as a food plant by the larvae of some Lepidoptera species including the Mouse Moth and the Anise Swallowtail.
# Appearance
Fennel is a perennial herb, meaning that it grows year-round. It is erect, glaucous green, and grows to heights of up to 2.5 m, with hollow stems. The leaves grow up to 40 cm long; they are finely dissected, with the ultimate segments filiform, about 0.5 mm wide. Its leaves are similar to those of dill, but thinner. The flowers are produced in terminal compound umbels 5–15 cm wide, each umbel section having 20–50 tiny yellow flowers on short pedicels. The fruit is a dry seed from 4–10 mm long, half as wide or less, and grooved.[2]
# Cultivation and uses
Template:Nutritionalvalue
Fennel is widely cultivated, both in its native range and elsewhere, for its edible, strongly-flavoured leaves and seeds. The flavour is similar to that of anise and star anise, though usually not as strong.[3]
The Florence fennel (Foeniculum vulgare Azoricum Group; syn. F. vulgare var. azoricum) is a Cultivar Group with inflated leaf bases which form a bulb-like structure. It is of cultivated origin,[4] and has a mild anise-like flavour, but is more aromatic and sweeter. Its flavour comes from anethole, an aromatic compound also found in anise and star anise. Florence fennel plants are smaller than the wild type and have inflated leaf bases which are eaten as a vegetable, both raw and cooked. There are several cultivars of Florence fennel, which is also known by several other names, notably the Italian name finocchio. In North American supermarkets, it is often mislabelled as "anise".
Fennel has become naturalised along roadsides, in pastures, and in other open sites in many regions, including northern Europe, the United States, southern Canada and in much of Asia and Australia. It propagates well by seed, and is considered an invasive species and a weed in Australia and the United States[5] (see Santa Cruz Island).
Florence fennel was one of the three main herbs used in the preparation of absinthe, an alcoholic mixture which originated as a medicinal elixir in Switzerland and became, by the late 19th century, a popular alcoholic drink in France and other countries. Due to the belief that absinthe possessed psychoactive properties beyond those of alcohol, it was banned in most countries by 1915, but a recent relaxation of laws governing its production, importation and sale has caused a moderate resurgence in modern day consumption. Fennel itself is known to be a stimulant,[6] although many modern preparations marketed under the name "absinthe" do not make use of it.
## Culinary uses
The bulb, foliage, and seeds of the fennel plant are widely used in many of the culinary traditions of the world. Fennel pollen is the most potent form of fennel, but also the most expensive. Dried fennel seed is an aromatic, anise-flavoured spice, brown or green in colour when fresh, slowly turning a dull grey as the seed ages. For cooking, green seeds are optimal.[3] The leaves are delicately flavored and similar in shape to those of dill. The bulb is a crisp, hardy root vegetable and may be sauteed, stewed, braised, grilled, or eaten raw.
Fennel seeds are sometimes confused with those of anise, which are very similar in taste and appearance, though smaller. In India, it is common to chew fennel seed (or saunf) as a mouth-freshener. Fennel is also used as a flavouring in some natural toothpaste. Some people employ it as a diuretic. Others use it to improve the milk supply of breastfeeding mothers, but it has shown neurotoxicity in certain cases where the mother ingested it as an herbal tea to enhance her breast milk.[7]
Fennel is most prominently featured in Italian cuisine, where bulbs and fronds appears both raw and cooked in side dishes, salads, pastas, and risottos. Fennel seed is a common ingredient in Italian sausages and meatballs and northern European rye breads.
Many cultures in the Indian subcontinent and the Middle East incorporate fennel seed into their culinary traditions. It is an essential ingredient in the Bengali/Oriya spice mixture panch phoron and in Chinese five-spice powders. It is known as saunf or mauti saunf in Hindi and Urdu, mouri in Bengali, shombu or peruncheeragam in Tamil language, variyali in Gujarati, and barishap in the Malay language.
Many egg, fish, and other dishes employ fresh or dried fennel leaves. Florence fennel is a key ingredient in some Italian and German salads, often tossed with chicory and avocado, or it can be braised and served as a warm side dish. It may be blanched or marinated, or cooked in risotto. In all cases, the leaves lend their characteristically mild, anise-like flavour.
## Medicinal uses
Fennel contains anethole, which can explain some of its effects: it, or its polymers, act as phytoestrogens.[8] On account of its aromatic and carminative properties, Fennel is chiefly used medicinally with purgatives to allay their side effects and for this purpose forms one of the ingredients of the well-known compound Liquorice Powder. Fennel water has properties similar to those of anise and dill water: mixed with sodium bicarbonate and syrup, these waters constitute the domestic 'Gripe Water,' used to correct the flatulence of infants. Essential oil of Fennel has these properties in concentration. Fennel tea, formerly also employed as a carminative, is made by pouring boiling water on a teaspoonful of bruised Fennel seeds. Syrup prepared from Fennel juice was formerly given for chronic coughs. Fennel is also largely used for cattle condiments. It is one of the plants which is said to be disliked by fleas, and powdered Fennel has the effect of driving away fleas from kennels and stables. [9]
# Etymology and history
The word fennel developed from the Middle English fenel or fenyl, which came from the Anglo-Saxon fenol or finol, which in turn came from the Latin feniculum or foeniculum, the diminutive of fenum or faenum, meaning "hay". The Latin word for the plant was ferula, which is now used as the genus name of a related plant.
In Ancient Greek, fennel was called marathon (μάραθον), and is attested in Linear B tablets as ma-ra-tu-wo. John Chadwick notes that this word is the origin of the place name Marathon (meaning "place of fennel"), site of the Battle of Marathon in 490 BC; however, Chadwick wryly notes that he has "not seen any fennel growing there now".[10] In Greek mythology, Prometheus used the stalk of a fennel plant to steal fire from the gods. Also, it was from the giant fennel, Ferula communis, that the Bacchanalian wands of the god Dionysus and his followers were said to have come.[11]
In medieval times fennel was used in conjunction with St John's wort to keep away witchcraft and other evil things. This practice may have originated from fennel's use as an insect repellent.[citation needed]
Fennel is thought to be one of the nine herbs held sacred by the Anglo-Saxons. (The other eight are not entirely certain, but were probably mugwort (Artemisia vulgaris), greater plantain (Plantago major), watercress (Nasturtium officinale), wild chamomile (Matricaria recutita), stinging nettle (Urtica dioica), crab apple (Malus sylvestris), chervil (Anthriscus cerefolium), and viper's bugloss (Echium vulgare).)
# Production
India is leader in production of Fennel followed by Syrian Arab Republic. | https://www.wikidoc.org/index.php/Fennel | |
33b0bebdcffda2a72257b5b5aea92ca28288fbf9 | wikidoc | Ferret | Ferret
The ferret is a domestic mammal of the type Mustela putorius furo. Domestic ferrets typically have brown, black, white, or mixed fur, have an average length of approximately 20 inches (51 cm) including a 5 inch (13 cm) tail, weigh about 2-4 pounds (1 kg), and have a natural lifespan of 7 to 10 years.
Several other small, elongated carnivorous mammals belonging to the family Mustelidae (weasels) also have the word "ferret" in their common names, including an endangered species, the Black-footed Ferret. The ferret is a very close relative of the polecat, but it is as yet unclear whether it is a domesticated form of the European Polecat, the Steppe Polecat, or some hybrid of the two.
The history of the ferret's domestication is uncertain, like that of most other domestic animals. It is very likely that ferrets have been domesticated for at least 2,500 years, but it is not certain for what purpose the ferret was originally domesticated. They are still used for hunting rabbits in some parts of the world today, but increasingly they are being kept simply as pets.
Being so closely related to polecats, ferrets are quite easily able to hybridize with them, and this has occasionally resulted in feral colonies of ferret polecat hybrids that have been perceived to have caused damage to native fauna, perhaps most notably in New Zealand. As a result, some parts of the world have imposed restrictions on the keeping of ferrets.
# History
Like most domestic animals, the original reason for ferrets' domestication by human beings is uncertain but it may have involved hunting. It was most likely domesticated from the European polecat (Mustela putorius), though it is also possible that ferrets are descendants of the Steppe polecat (Mustela eversmannii), or some hybridization thereof. Analysis of mitochondrial DNA suggests that ferrets were domesticated around 2,500 years ago, although what appear to be ferret remains have been dated to 1500 BC. It has been claimed that the ancient Egyptians were the first to domesticate ferrets, but as no mummified remains of a ferret have yet been found, or any hieroglyph of a ferret, and no polecat now occurs wild in the area, that idea seems unlikely.
The Greek word ictis occurs in a play written by Aristophanes, The Acharnians, in 425 BC. Whether this was actually a reference to ferrets, polecats, or the similar Egyptian Mongoose is uncertain.
The name "ferret" is derived from the Latin furittus, meaning "little thief", a likely reference to the common ferret penchant for secreting away small items. Ferrets were probably used by the Romans for hunting.
Colonies of feral ferrets have established themselves in areas where there is no competition from similarly sized predators, such as in the Shetland Islands. Where ferrets coexist with polecats, hybridization is common. It has been claimed that New Zealand has the world's largest feral population of ferret-polecat hybrids. In 1877, farmers in New Zealand demanded that ferrets be introduced into the country to control the rabbit population, which was also introduced by humans. Five ferrets were imported in 1879, and in 1882-1883, 32 shipments of ferrets were made from London, totaling 1,217 animals. Only 678 landed, and 198 were sent from Melbourne, Australia. On the voyage, the ferrets were mated with the European polecat, creating a number of hybrids that were capable of surviving in the wild. In 1884 and 1886, close to 4,000 ferrets and ferret hybrids, 3,099 weasels and 137 stoats were turned loose. Concern was raised that these animals would eventually prey on indigenous wildlife once rabbit populations dropped, and this is exactly what happened to New Zealand bird species which previously had no mammalian predators.
## Ferreting
For hundreds of years, the main use of ferrets was for hunting, or ferreting. With their long, lean build and inquisitive nature, ferrets are very well equipped for getting down holes and chasing rodents and rabbits out of their burrows. Caesar Augustus sent ferrets or mongooses (named "viverrae" by Plinius) to the Balearic Islands to control the rabbit plagues in 6 BC. They are still used for hunting in some countries, including the United Kingdom, where rabbits are considered a plague species. However, the practice is illegal in several countries where it is feared that ferrets could unbalance the ecology.
In England, in 1390, a law was enacted restricting the use of ferrets for hunting to those of substantial means:
Ferrets were first introduced into the New World in the 17th century, and were used extensively from 1860 until the start of World War II to protect grain stores in the American West.
# Ferrets as pets
In the United States, ferrets were relatively rare pets until the 1980s. Dr. Wendy Winstead, a veterinarian and former folk singer who had her first ferret in 1969, sold ferrets to a number of celebrities including Dick Smothers and David Carradine while making television appearances on programs such as the David Letterman Show with ferrets in the 1980s, writing books and promoting them until her death in the 1990s from cancer. A government study by the California State Bird and Mammal Conservation Program found that by 1996, approximately 800,000 or so domestic ferrets were likely being kept as pets in the United States.
## Activity and nature
Ferrets spend 14 to 18 hours a day sleeping and are naturally crepuscular, meaning they are most active during dusk and dawn. Though ferrets sleep more than most domesticated animals, they are very active when awake and will seek to be released from their cage to get exercise and satisfy their abundant curiosity daily.
Ferrets are energetic, curious, interested in their surroundings, and often actively solicit play with humans, having a repertoire of behaviors both endearing and difficult for some human owners. Play for a ferret will often involve hide-and-seek games, or some form of predator/prey game in which either the human attempts to catch the ferret or the ferret to catch the human. They also have a strong nesting instinct and will repeatedly carry small objects to hidden locations. It is difficult to predict what objects ferrets will attempt to hoard, with owners reporting play toys, socks, bags of onions, pizza slices, keys, calculators, silverware, aluminum foil, shoes, sponges, toilet paper rolls, textbooks, video game controllers, footballs, etc. Ferrets will seemingly form attachments to certain objects and will repeatedly 'steal' the same object and bring it to their hiding place.
Ferrets are easily entertained and do not require pet toys; however, most kitten toys work well with ferrets. Ferrets love playing tug of war with toys and stuffed animals. Ferrets will also tear open packages and other containers to see what is inside or explore the inside of the package. Ferrets are interested in holes, pipes and other small enclosed areas, and seem compelled to explore holes. Thus a cardboard or plastic tube will be appreciated. Ferrets are especially fond of variety in their toy selection - bell-balls, crinkle tubes, and paper bags will work well. All toys should be mixed up regularly, as ferrets will often grow bored of playing the same games repeatedly.
When ferrets are excited, they may perform a routine commonly referred to as the weasel war dance, a frenzied series of sideways hops. This is often accompanied by a soft clucking noise, commonly referred to as dooking. It is often an invitation to play or an expression of happy excitement and is not threatening.
The ferret's posture may become rigid with wide open jaws, momentary eye contact followed by thrashing or turning of the head from side to side, arching the back, piloerection, and hopping to the side or backwards while facing the intended playmate. This is often accompanied by an excited panting sound that may sound like a hiss. Often, this behavior will break into a game of chase, pounce and wrestle. Ferrets in war dances are very accident prone, often hopping into obstacles or tripping over their own feet.
Ferrets tend to nip as kits. Nipping is the act of biting in a playful manner representative of mock fighting and sparring; young ferrets are also more prone to chewing and teething, and have a tendency to bite harder. Older ferrets tend to chew far less frequently and, when trained correctly, almost never nip a human hand or only do so very gently. However, ferrets that have been abused or are in extreme pain may bite a human, and are capable of strong bites which break through the skin.
Ferrets, like cats, can use a litter box with training, but they are not always completely litter box trainable. Their instinct is to spread their waste in order to scent mark a wider foraging territory for themselves; thus, multiple litter boxes may be necessary, and all litter areas should be changed frequently.
A common ferret problem to many pet owners is introducing new ferrets to their population. Senior ferrets may seem excessively violent to unknown ferrets in their home, but adding another ferret to ones population to decrease boredom or for breeding will greatly encourage the morale of the ferret or ferret population one owns. Males and females will exhibit much stronger territorial urges when confronted with a new ferret, and will often treat the new ferret like a toy. After a fighting period which should be monitored but only rarely results in harm to a ferret, the older ferret will show its dominance, often by dragging the junior ferret around by the scruff of the neck to its hoard and leaving it like any other object it values. Given time and careful monitoring, new ferrets will almost always be accepted by the older ferret or group. Young ferrets can actually benefit from having an older house trained ferret around when being taught to use a litter box, take baths, or have their nails clipped.
## Diet
Ferrets are obligate carnivores and the natural diet of their wild ancestors consisted of whole small prey, i.e., meat, organs, bones, skin, feathers, and fur. Some ferret owners feed a meat-based diet consisting of whole prey like mice and rabbits along with raw meat like chicken, beef, veal, kangaroo and wallaby. This is preferred in Europe and Australia, and becoming increasingly popular in the United States due to concern over high carbohydrate levels in some processed ferret foods.
Alternatively, there are many commercial ferret food products. Some kitten foods can also be used, so long as they provide the high protein and fat content required by the ferret's metabolism. Most adult cat foods and kitten foods are unsuitable for ferrets however, because of their low protein content and high fiber. Ideally, a ferret food should contain a minimum of 32% meat based protein and 18% fat. Low-quality pet foods often contain grain-based proteins, which ferrets cannot properly digest.
Ferrets may have a fondness for sweets like raisins, bananas, peanut butter, and pieces of cereal. The high sugar content of such treats has been linked to ferret insulinoma and other diseases. Veterinarians recommend not feeding raisins and the like to ferrets at all. Also, like many other carnivores, ferrets gradually lose the ability to digest lactose after they are weaned. As a result, lactose-free milk is to be preferred.
Many ferrets are sold very young. Sometimes a ferret will be sold too young; after consultation with a veterinarian, it should be fed a mix of crushed or soft food mixed with milk slightly warmed, until the veterinarian advises otherwise.
## Dangers to ferrets
Ferret curiosity often exceeds common sense and ferrets are good at getting into holes in walls, doors, cupboards, or in or behind household appliances such as clothes dryers and dishwashers, where they can be injured or killed by drowning, electrical wiring, fans, and other household items. Many enjoy chewing items made of soft rubber, foam, or sponge, which present the risk of intestinal blockage and death if ingested. Serious and sometimes fatal injuries have resulted from ferrets chewing on electrical cords. Screen doors can be damaged by a ferret's claws, and dryer vents often become escape routes to the outdoors.
Unlike dogs and cats, many ferrets display little homing instinct and do not thrive as strays. Ferret owners frequently train ferrets at a young age to respond to clicker toys, or to the sound of their own food being shaken, as a means of recovering a ferret which has ventured too far from its home. In all cases, the escape of a ferret should be addressed immediately, as wandering ferrets may be easily injured or killed by neighborhood animals, local wildlife, or passing vehicles.
Recliners and fold-out sofas are a leading cause of accidental death in ferrets. Ferrets will often climb inside the springs and can be injured or killed once the chair is put into a reclined position.
For these reasons, owners usually "ferret-proof" their home, the task of carefully going through each room, removing items dangerous to ferrets and covering over any holes or potential escape routes. As ferrets can open improperly latched cupboards or doors by rolling over and clawing at the bottom edge, childproof latches are often used and owners keep cleaning products in high, out-of-reach places. However, ferrets can typically fit through any hole as small as the size of their head, making some childproof latches ineffective.
Some owners may prefer to house their pets outdoors in sheds, and not indoors. This is becoming more popular, due to speculation on the possible effects of the photoperiod effect on the ferret adrenal gland.
When a ferret is outdoors, an owner must take additional care during mosquito and tick season, as ferrets are susceptible to the diseases carried by these parasites. Ticks can attach themselves and begin to draw blood. When the tick gets full, it regurgitates some blood and tick saliva back into the ferret, which is how Lyme and other diseases can be transmitted. Ordinarily, the regurgitation happens between five to 24 hours after the tick attaches. Early removal of ticks using proper methods to avoid tick regurgitation, and prevention when in environments where encountering ticks is essential. Additionally, mosquitoes may carry heart worms and the West Nile virus. Fleas can cause extreme skin irritation and can be intermediate hosts for tapeworms, one of which may kill a ferret because of their small size. Similarly, the venom of a bee, wasp or spider is much more serious for a ferret than for a larger mammal, and ferrets can be regarded as prey by hawks, and by large snakes.
Ferrets are fearless to the point of foolishness and should not be allowed to wander. Whenever they are outside, they should be closely supervised and preferably kept on a harness leash designed for ferrets such as an H-shaped harness. Their curious nature also leads them to place themselves in situations where they will confront and try to play with larger animals outdoors that may be dangerous to the ferret.
Ferrets have been known to play well with household cats and some non-aggressive dogs, however, great care must be taken when introducing ferrets to any other household pets. Certain terrier dog breeds even have a heightened instinct to grab and kill ferrets. Many breeders these days prefer to raise their young kits with prey animal (baby & adult mouse, chicken, hamster, rats etc) instead of giving dry food. Therefore, ferrets may attack and kill pets like rodents, birds, and small reptiles, which may have been the prey of their wild ancestors.
## Ferrets and children
Ferrets can make good pets for some children, but usually do not make good pets for very young children. Important considerations include assessing potential danger to a human child by a pet ferret, and potential danger to a pet ferret by a human child, either deliberately or by neglect.
Ferrets are capable of delivering a bite almost as strong as a domestic cat. Like all other domesticated animals, they should never be left unsupervised near infants or very young children. There have been rare cases where ferrets have severely injured babies but nearly all such incidents involved neglect, abuse, or roughhousing that the ferret likely perceived as an attack, and some of the animals involved were ferret-polecat hybrid crosses. Given that young children and ferrets can be both excitable and prone to rough play, interaction between ferrets and children must always be closely supervised for the protection of both.
With regard to the danger of potential pet ferret attacks as contrasted to attacks from other pet species, statistics would imply that the danger is probably overstated. In the United States, a government study by the California Department of Health Services on national pet attack statistics found 452 reported incidents of ferret bites during the ten year period 1978-1987. By comparison, pet dogs accounted for an estimated 585,000 injuries that required medical attention in the year 1986 alone, with the total number of pet dogs in the United States in 1996 estimated at 55,000,000 and the total number of pet ferrets in the United States in 1996 estimated at 800,000. Adjusting for the proportionate ratio of dogs to ferrets in the United States of 68 to 1, dog bites occurred 190 times more often than ferret bites.
As the possible danger to a human child by a pet ferret must be assessed, the possible danger to a pet ferret by a human child should also be considered in determining whether or not a ferret will make a good pet for a child. Younger children may play too rough with a ferret, or fail to anticipate the physical danger to a ferret from things like closing doors, heavy objects, or accidentally stepping on the animal during play, all of which may lead to severe injury, and often the need for surgery, for the ferret involved. Repeated rough play may psychologically and physically stress the ferret and increases the likelihood of a provocation and a defensive response or bite from the animal. Additionally, as with any pet, young children may fail to appreciate the responsibilities of care and maintenance of their ferret, including attention to proper food and water supply, cage and litter maintenance, grooming, and the need for daily activity and attention when the ferret is alert and active. If a parent or responsible party is not present and willing to step in and fulfill these needs, a ferret is likely a poor choice of pet for a child, due to the problem of neglect.
For children who demonstrate responsible behavior, in regard to both playing with their pet and to consistent care and maintenance, ferrets can make good pets and are often loved by children for their social personalities and engaging antics.
## Other uses of ferrets
Ferrets have been used to run wires and cables through large conduits. Event organizers in London used ferrets to run TV and sound cables for both the wedding of Charles, Prince of Wales to Lady Diana Spencer, and for the "Party in the Park" concert held in Greenwich Park on Millennium Eve. One ferret, Freddie, was even registered as an electrician's assistant with the New Zealand Electrical Workers Union.
Because they share many anatomical and physiological features with humans, ferrets are extensively used as experimental subjects in biomedical research, in fields such as virology, reproductive physiology, anatomy, endocrinology and neuroscience.
### Ferrets' role in prescription medication disposal
SAMHSA spokesman Mark Weber listed ferret waste as an alternative to using coffee grinds for the safe disposal of prescription medicine. This method has dual purpose: to keep prescription medications from being abused, and to minimize the effect on fish and amphibians from medications flushed down the toilet.
# Ferret biology and health concerns
Ferrets do not require frequent bathing, which may remove natural oils in the ferrets coat that prevent dry skin. However, most ferrets are not averse to water. Ferrets also need their nails clipped on a regular basis, and usually shed twice a year in the spring and fall. A laxative is sometimes administered, to help any ingested fur pass more easily through the digestive tract.
Ferret bedding should be washed or changed regularly, and the litter box cleaned frequently, which significantly lessens any unpleasant odors. Due to their low carriage and their sensitive mucous membranes, ferrets are extremely sensitive to dust in their environment and many cat litters may be unsuitable for them. Also, a clumping cat litter may be ingested and cause blockages. A litter made from recycled paper material or organic material (e.g. corn or wheat) is preferred.
Most veterinarians recommend an annual health checkup. Ferrets often hide symptoms of illness very well, so any unusual behavior is considered good cause for a medical consultation. As ferrets have high metabolisms and cancers can progress at a fast rate, early detection is critical for successful treatment.
Like many other carnivores, ferrets have scent glands near their anuses, the secretions from which are used in scent marking. It has been reported that ferrets can recognize individuals from these anal gland secretions, as well as the sex of unfamiliar individuals. Ferrets may also use urine marking for sex and individual recognitions.
Like skunks, ferrets can release their anal gland secretions when startled or scared, but the smell dissipates rapidly. Most pet ferrets in the US are sold de-scented, with their anal glands removed. In the UK, many consider de-scenting an unnecessary mutilation. In Australia and the UK, the general opinion is that the animal does not need to be de-scented. The Netherlands and other parts of Europe consider this practice to be animal abuse.
Males, if not neutered, are extremely musky. It is considered preferable to delay neutering until sexual maturity has been reached, at approximately 6-8 months old, after the full descent of the testicles. Neutering the male will reduce the smell to almost nothing. The same applies for females, but spaying them is also important for their own health. Unless they are going to be used for breeding purposes, female ferrets will go into extended heat and an unbred female without medical intervention can die of aplastic anemia.
Many domestic ferrets are known to suffer from several distinct health problems. Among the most common are cancers affecting the adrenal glands, pancreas, and lymphatic system. Some health problems have been linked to ferrets being neutered before sexual maturity was reached, because of this some owners now choose to use implants instead of having the ferret neutered too early. Some owners even choose not to have their ferret neutered at all but use longer working implants instead. Certain colors of ferret may also carry a genetic defect known as Waardenburg syndrome .
Many of the diseases present in ferrets can cause severe weight loss, which, due to their size, can be an even more extreme problem than in some other animals. Ferrets suffering from extreme weight loss or with sensitive digestive tracts are often recommended to be fed a mixture called "duck soup." This usually contains a high-fat, high-protein, low-fiber mixture of a whole chicken (innards and all), fat drippings, Nutrical, Ferretone, high-grade kitten food, and several other ingredients, variant on recipe. "Duck soup" helps ensure that a ferret keeps his or her weight up and is easy on the intestines.
Dehydrated ferrets may also be given Pedialyte.
## Adrenal disease
Adrenal disease, a growth of the adrenal glands that can be either hyperplasia or cancer, is most often diagnosed by signs like unusual hair loss, increased aggression, difficulty urinating or defecating, or agitation when urinating, and (in the case of females) an enlarged vulva. Even if the growth is benign, it can still cause a hormonal imbalance which can have devastating effects on the ferret's health.
Treatment options include surgery to excise the affected glands, melatonin implants, which treat the symptoms but not the disease itself, and/or hormone therapy. The causes of adrenal disease are as yet uncertain, but speculated triggers include unnatural light cycles, diets based around processed ferret foods, and prepuberty neutering. It has also been suggested that there may be a hereditary component to adrenal disease.
Adrenal disease is usually detected during the spring or fall. This is because adrenal disease affects the hormones that make the fur grow, so when ferrets with adrenal disease shed their winter coat they simply don't grow it back because of the disease. The hair loss pattern is usually very specific for adrenal disease: It begins at the base of the tail and then continues up the ferret's back. Ferrets who have been treated for adrenal disease may also suffer temporary but severe hair loss as their bodies recover.
## Insulinoma
Ferrets are also known to suffer from insulinoma, a cancer of the pancreas. The growth of cancerous nodules on the lobes of the pancreas sometimes, but not always, leads to an increase in the production of insulin, which regulates the rate at which the ferret's body metabolizes blood glucose. Too much insulin will cause blood sugar to drop, resulting in lethargy, seizures, and ultimately death. Symptoms of an insulinoma attack include episodes of lethargy, drooling, pawing and/or foaming at the mouth, high pitched screams, staring "blankly" into space, and seizures.
Like adrenal cancer, the exact cause of insulinoma is unknown. It is speculated that the diets of domestic ferrets are too far removed from the natural diets of their polecat ancestors, and include too much sugar or simple carbohydrates.
Treatment for insulinoma may include surgical excision of the cancerous lobes, pharmaceutical treatment with steroids that suppress the production of insulin, supplemental changes in diet (most often poultry-based baby food), or a combination thereof. Unfortunately, the growth of the tumors cannot be completely stopped, and the ferret will eventually suffer a recurrence of symptoms. In an insulinoma attack, a temporary remedy to stabilize the ferret is any kind of a sugary syrup, such as corn syrup or honey.
## Lymphoma
Lymphoma/lymphosarcoma is the most common malignancy in ferrets. Ferret lymphosarcoma occurs in two forms -- juvenile lymphosarcoma, a fast-growing type that affects ferrets younger than two years, and adult lymphosarcoma, a slower growing form that affects ferrets four to seven years old.
In juvenile ferret lymphosarcoma, large, immature lymphocytes (lymphoblasts) rapidly invade the thymus and/or the organs of the abdominal cavity, particularly the liver and spleen. In adult ferret lymphosarcoma, the lymph nodes in the limbs and abdominal cavity become swollen early on due to invasion by small, mature lymphocytes. Invasion of organs, such as the liver, kidney, lungs, and spleen, occurs later on, and the disease may be far advanced before symptoms are noticeable.
As in humans, ferret lymphosarcoma can be treated surgically, with radiation therapy, chemotherapy or a combination thereof. The long-term prognosis is rarely bright, however, and this treatment is intended to improve quality of life with the disease.
## Viral diseases
Epizootic catarrhal enteritis (ECE)
ECE, a viral disease that first appeared in the northeastern US in 1994, is an inflammation of the mucous membranes in the intestine. The disease manifests itself as severe diarrhea (often of a bright green color), loss of appetite, and severe weight loss. The virus can be passed via fluids and indirectly between humans. Although it was often fatal when first discovered, ECE is less of a threat nowadays with the right supportive care which usually includes hospitalization with intravenous fluids. The virus is especially threatening to older ferrets and requires immediate attention.
Aleutian disease virus (ADV)
Aleutian Disease Virus (ADV) is a parvovirus discovered among mink in the Aleutian Islands in the early 20th century. In ferrets, the virus affects the immune system (causing it to produce non-neutralizing antibodies) and many internal organs, particularly the kidneys. There is no cure or vaccine for the disease, and ferrets may carry the virus for months or years without any external symptoms. As a result, some ferret organizations and shelters recommend that owners test their pets for the virus regularly, separating them from other ferrets if they test positive.
Canine distemper
Canine distemper (CD) is an extremely contagious virus that is almost always fatal. Being strict indoor pets does not necessarily protect ferrets, as owners may bring the virus home on their clothes or their shoes. The only protection against the virus is vaccination, but that is not without controversy as there have been reports, particularly from the USA, of ferrets going into anaphylactic shock after being vaccinated against CD.
Influenza virus isolation using ferrets
Ferrets have served as a good experimental animal models in the study of influenza virus. Smith, Andrews, Laidlaw(1933)inoculated ferrets intra-nasally with human naso-pharyngeal washes, which produced a form of influenza that spread to other cage mates. The human influenza virus(Influenza type A) was transmitted from an infected ferret to a junior investigator , from whom it was subsequently re-isolated.
## Waardenburg-like coloring
Ferrets with a white stripe on their face or a fully white head, primarily blazes, badgers, and pandas, almost certainly carry a congenital defect which shares some similarities to Waardenburg syndrome. This causes, among other things, a cranial deformation in the womb which broadens the skull, causing the white face markings but also partial or total deafness. It is estimated as many as 75% of ferrets with these Waardenburg-like colorings are deaf. Beyond that, the cranial deformation also causes a higher instance of stillborn ferret kits, and occasionally cleft palates. Because of this, many breeders will not breed Waardenburg-patterned ferrets.
# Terminology and coloring
Male intact ferrets are called hobs; female intact ferrets are jills. A spayed female is a sprite, and a neutered male is a gib. Ferrets under one year old are known as kits. A group of ferrets is known as a business.
Ferrets come in a variety of coat colors and patterns. The ones recognized by the American Ferret Association are as follows:
White ferrets were favored in the Middle Ages for the ease in seeing them in thick undergrowth. Leonardo's painting Lady with an Ermine is likely mislabeled; the animal is probably a ferret, not a stoat, for which "ermine" is an alternative name (the latter strictly applying only to the animal in its white winter coat). Similarly, the Ermine portrait of Queen Elizabeth the First shows her with her pet ferret, who has been decorated with painted-on heraldic ermine spots.
"The Ferreter's Tapestry" is a fifteenth-century tapestry from Burgundy, France now part of the Burrell Collection housed in the Glasgow Museum and Art Galleries. It shows a group of peasants hunting rabbits with nets and white ferrets.
"Pope Celestinus III Grants Privilege of Independence to the Spedale" painted by Domenico di Bartolo in 1443 shows a fashionable man with a colored pet ferret wearing a red collar on his shoulder. This image was reproduced in Renaissance Dress In Italy 1400-1500, by Jacqueline Herald, Bell & Hyman - ISBN 0-391-02362-4
Gaston Phoebus' Book Of The Hunt was written in approximately 1389 to explain how to hunt different kinds of animals, including how to use ferrets to hunt rabbits. Illustrations show how multicolored ferrets that are fitted with muzzles were used to chase rabbits out of their dens and into waiting nets.
# Ferrets featured in literature and culture
- In the 1984 made-for-TV movie Caravan of Courage: An Ewok Adventure, the main character Cindel plays with Wicket's pet ferret in a scene shortly after their "star cruiser" crashed.
- The Greek playwright Aristophanes made reference to ferrets in his satire The Acharneans written around the year 425 BC. "What a happy man he’ll be that marries you and begets a set of Ferrets as good as you at farting in the Grey dawn!".
- The main character in the Japanese manga series Peach Fuzz is a ferret named Peach who has delusions of being a princess.
- The title character of the short story Sredni Vashtar by Edwardian satirist Saki is a "polecat-ferret" clandestinely kept by a young boy, who is liberated when the animal he worships as a god kills his overbearing guardian.
- The children's book Zucchini by Barbara Dana is about a boy and his pet ferret. However, the author gets a number of basic ferret facts wrong, claiming that they are vegetarian rodents.
- Former Doctor Who lead actor Sylvester McCoy got his acting start as Sylvester McCoy, the Human Bomb, a stage act that consisted of stuffing live ferrets down his trousers.
- In the film The Big Lebowski, Lebowski is attacked in the bathroom by a "Marmot" which is really a ferret.
- In the film Kindergarten Cop, John Kimble (played by Arnold Schwarzenegger) owns a pet ferret, which becomes the mascot of his kindergarten class and saves his life by biting the main antagonist near the end of the film.
- In the film Starship Troopers, Colonel Carl Jenkins (played by Neil Patrick Harris) owns a pet ferret, which he mischievously tells (via Telepathy) to go and find a treat up his mother's leg.
- Richard Bach, author of Jonathan Livingston Seagull, has written five books starring ferrets, the Ferret Chronicles series.
- In the 2004 romantic comedy Along Came Polly, Jennifer Aniston's character, Polly, owns a blind ferret who often runs head-first into stationary objects, to great comic effect. The ferret is featured in the promotional material for the film.
- The film and TV series The Beastmaster has two ferrets, Kodo & Podo, which appear as major characters. The series' protagonist usually kept them in a small pouch attached to his belt.
- In the fourth Harry Potter book and film, Harry Potter and the Goblet of Fire, the character Draco Malfoy is turned into an albino ferret.
- The BBC children's television magazine program Xchange featured the puppet Vinnie, a mischievous ferret.
- HTV Wales has a long-running investigation series called The Ferret.
- Ferrets are the obvious suspects in the mystery novel "Nothing to Fear but Ferrets" by Linda O. Johnston.
- Budweiser (Anheuser-Busch) has used a fictitious ferret in a series of radio commercials.
- Bill Owen's character Compo in the BBC series Last of The Summer Wine (1973) had two ferrets which caused an uproar at a funeral in one episode.
- Japanese Media: Ferrets have appeared in the manga Ask the Stars for Help ( 困った時には星に聞け! ) by Miyuki Abe ( あべ 美幸 ) and in the anime series Nanoha ( なのは ) - "In a failed attempt to seal a seed properly, he winds up on Earth in the form of a ferret." The character Yūno Scrya has an animal form as a ferret.
- The popular webcomic, Sluggy Freelance has a main character named Kiki who is a ferret.
- A ferret called Fungo Squiggly is one of the supporting characters in the Get Fuzzy comic strip by Darby Conley.
- In Degrassi: The Next Generation Ellie Nash owns a ferret name Bueller for a short time until he dies due to chewing on electrical wires.
- In the Pokémon series, the pokemon called Furret is based on a ferret.
- There are numerous ferrets in the Redwall series by Brian Jacques.
- Paris Hilton once owned a ferret. She walked the red carpet with it many times, and was publicly scrutinized for taking the ferret, as well as several other animals, to social events.
- On Tucker Carlson Live, Rudy Giuliani tells a man who called in asking why he banned ferrets in New York City that "The excessive concern that you have for ferrets is a sickness that you should examine with a therapist."
- In the cartoon series The Littles, Dr. Hunter had a ferret which he often used to try to capture the Littles.
- In a commercial for Diet Mountain Dew, a ferret walks through the woods with a hockey mask and a chainsaw, chasing two teens.
- The character Bandit is a ferret on the webcomic The Whiteboard.
- The 1st Battalion, the Yorkshire Regiment of the British Armed Forces, keeps two ferrets, Imphal and Quebec, as its unofficial mascots, named after the battalion's battle honors.
- In the manga and anime Strawberry Marshmallow (苺ましまろ, Ichigo Mashimaro) by Barasui, the character Matsuri Sakuragi owns a pet ferret named John.
- In the manga Ai Yori Aoshi by Kou Fumizuki, Miyabi Kagurazaki acts as the main caretaker of an explorative albino ferret named Uzume.
- In the anime and manga Infinite Ryvius, the character Fina owns a ferret named Rafra.
- In the Babymouse series, Babymouse's Best friend is a ferret named Wilson
- The children's book Poggin Tails by Nick Cooper is a collection of short stories featuring Poggin, a polecat.
- In the animated children's series Iggy Arbuckle, the characters Robear and Robert are ferrets.
- In the TV show Ned's Declassified School Survival Guide, Gordy is always over-elaborately hunting a "weasel" which is really a stuffed ferret.
- In the 2007 film The Golden Compass, the daemon Pantalaimon spends much of the film as a ferret-like animal.
- In the 2007 film Stardust, the witch Empusa is attacked and devoured by ferrets and wolves.
- French poet Jean Follain wrote the 75-word poem "Death of the Ferret".
- In the, as yet unreleased, movie, Inkheart, based on the book by Cornelia Funke, one of the main characters, the fire-eater, Dustfinger, owns a pet marten, Gwin, which is replaced in the film by a 'polecat' or sable ferret.
# Regulation on ferrets as pets
- Australia It is illegal to keep ferrets as pets in Queensland or the Northern Territory; in the ACT a license is required.
- Brazil Ferrets are becoming popular. They are only allowed if they are given a microchip identification tag and sterilized.
- Iceland Selling, distributing, breeding and keeping ferrets is illegal in Iceland.
- New Zealand It has been illegal to sell, distribute or breed ferrets in New Zealand since 2002.
- Portugal It is illegal to keep ferrets as pets in Portugal. Ferrets can only be used for hunting purposes and can only be kept with a government permit.
- United States Ferrets were once banned in many US states, but most of these laws were rescinded in the 1980s and 90s as they became popular pets. Ferrets are still illegal in California under Fish and Game Code Section 2118 and the California Code of Regulations. Additionally, "Ferrets are strictly prohibited as pets under Hawaii law because they are potential carriers of the rabies virus"; the territory of Puerto Rico has a similar law. Ferrets are also restricted by individual cities, such as, Washington, DC and New York City. They are also prohibited on many military bases. A permit to own a ferret is needed in other areas, including Rhode Island. Illinois and Georgia do not require a permit to merely possess a ferret, but a permit is required to breed ferrets. It was once illegal to own ferrets in Dallas, Texas, but the current Dallas City Code for Animals includes regulations for the vaccination of ferrets.
## Travel regulations
### Airline policies
Most airlines require advance booking for ferret travel, and may levy additional fees. Requirements concerning pet carrier size, weight, and construction may vary from airline to airline. In the U.S., Delta Airlines is the only airline to allow ferrets in the cabin during a flight.
### Train policies
### Import laws
Ferrets are legal in most US states except, California, and Hawaii .
Ferrets cannot be imported into Australia at all. A report drafted in August 2000 seems to be the only effort made to date to change the situation.
Ferrets brought from anywhere except the US require a Permit to Import from the Canadian Food Inspection Agency Animal Health Office. Ferrets from the US require only a vaccination certificate signed by a veterinarian. Ferrets under three months old are not subject to any restrictions for importation.
As of July 2004, dogs, cats, and ferrets can travel freely within the European Union under the PETS travel scheme. To cross a border within the EU, ferrets require at minimum an EU PETS passport and an identification microchip (though some countries will accept a tattoo instead). Vaccinations are also required; most countries require a rabies vaccine, and some also require a distemper vaccine and treatment for ticks and fleas 24 to 48 hours before entry. PETS travel information is available from any EU veterinarian or on government websites.
Although previously pet ferrets were allowed to be brought into Japan, that is no longer the case. Individual pet ferrets cannot be brought into Japan without proper documents. However, licensed breeders such as Canadian Farms, PVF, Marshall's, etc... have a special agreement that still allows the import of those ferrets from those companies.
The UK accepts ferrets under the PETS travel scheme. Ferrets must be microchipped, vaccinated against rabies, and documented. They must be treated for ticks and tapeworms 24 to 48 hours before entry. They must also arrive via an authorized route. Ferrets arriving from outside the EU may be subject to a six-month quarantine. | Ferret
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The ferret is a domestic mammal of the type Mustela putorius furo. Domestic ferrets typically have brown, black, white, or mixed fur, have an average length of approximately 20 inches (51 cm) including a 5 inch (13 cm) tail, weigh about 2-4 pounds (1 kg),[1] and have a natural lifespan of 7 to 10 years.[2][3][4]
Several other small, elongated carnivorous mammals belonging to the family Mustelidae (weasels) also have the word "ferret" in their common names, including an endangered species, the Black-footed Ferret. The ferret is a very close relative of the polecat, but it is as yet unclear whether it is a domesticated form of the European Polecat, the Steppe Polecat, or some hybrid of the two.
The history of the ferret's domestication is uncertain, like that of most other domestic animals. It is very likely that ferrets have been domesticated for at least 2,500 years, but it is not certain for what purpose the ferret was originally domesticated. They are still used for hunting rabbits in some parts of the world today, but increasingly they are being kept simply as pets.
Being so closely related to polecats, ferrets are quite easily able to hybridize with them, and this has occasionally resulted in feral colonies of ferret polecat hybrids that have been perceived to have caused damage to native fauna, perhaps most notably in New Zealand. As a result, some parts of the world have imposed restrictions on the keeping of ferrets.
# History
Like most domestic animals, the original reason for ferrets' domestication by human beings is uncertain but it may have involved hunting. It was most likely domesticated from the European polecat (Mustela putorius), though it is also possible that ferrets are descendants of the Steppe polecat (Mustela eversmannii), or some hybridization thereof.[5] Analysis of mitochondrial DNA suggests that ferrets were domesticated around 2,500 years ago, although what appear to be ferret remains have been dated to 1500 BC.[6] It has been claimed that the ancient Egyptians were the first to domesticate ferrets, but as no mummified remains of a ferret have yet been found, or any hieroglyph of a ferret, and no polecat now occurs wild in the area, that idea seems unlikely.[7]
The Greek word ictis occurs in a play written by Aristophanes, The Acharnians, in 425 BC. Whether this was actually a reference to ferrets, polecats, or the similar Egyptian Mongoose is uncertain.[8]
The name "ferret" is derived from the Latin furittus, meaning "little thief", a likely reference to the common ferret penchant for secreting away small items.[9] Ferrets were probably used by the Romans for hunting.[10][11]
Colonies of feral ferrets have established themselves in areas where there is no competition from similarly sized predators, such as in the Shetland Islands. Where ferrets coexist with polecats, hybridization is common. It has been claimed that New Zealand has the world's largest feral population of ferret-polecat hybrids.[12] In 1877, farmers in New Zealand demanded that ferrets be introduced into the country to control the rabbit population, which was also introduced by humans. Five ferrets were imported in 1879, and in 1882-1883, 32 shipments of ferrets were made from London, totaling 1,217 animals. Only 678 landed, and 198 were sent from Melbourne, Australia. On the voyage, the ferrets were mated with the European polecat, creating a number of hybrids that were capable of surviving in the wild. In 1884 and 1886, close to 4,000 ferrets and ferret hybrids, 3,099 weasels and 137 stoats were turned loose.[13] Concern was raised that these animals would eventually prey on indigenous wildlife once rabbit populations dropped, and this is exactly what happened to New Zealand bird species which previously had no mammalian predators.
## Ferreting
For hundreds of years, the main use of ferrets was for hunting, or ferreting. With their long, lean build and inquisitive nature, ferrets are very well equipped for getting down holes and chasing rodents and rabbits out of their burrows. Caesar Augustus sent ferrets or mongooses (named "viverrae" by Plinius) to the Balearic Islands to control the rabbit plagues in 6 BC.[14] They are still used for hunting in some countries, including the United Kingdom, where rabbits are considered a plague species. However, the practice is illegal in several countries where it is feared that ferrets could unbalance the ecology.
In England, in 1390, a law was enacted restricting the use of ferrets for hunting to those of substantial means:
Ferrets were first introduced into the New World in the 17th century, and were used extensively from 1860 until the start of World War II to protect grain stores in the American West.
# Ferrets as pets
In the United States, ferrets were relatively rare pets until the 1980s. Dr. Wendy Winstead, a veterinarian and former folk singer who had her first ferret in 1969, sold ferrets to a number of celebrities including Dick Smothers and David Carradine while making television appearances on programs such as the David Letterman Show with ferrets in the 1980s,[17] writing books and promoting them until her death in the 1990s from cancer. A government study by the California State Bird and Mammal Conservation Program found that by 1996, approximately 800,000 or so domestic ferrets were likely being kept as pets in the United States.[18]
## Activity and nature
Ferrets spend 14 to 18 hours a day sleeping and are naturally crepuscular, meaning they are most active during dusk and dawn. Though ferrets sleep more than most domesticated animals, they are very active when awake and will seek to be released from their cage to get exercise and satisfy their abundant curiosity daily.
Ferrets are energetic, curious, interested in their surroundings, and often actively solicit play with humans, having a repertoire of behaviors both endearing and difficult for some human owners. Play for a ferret will often involve hide-and-seek games, or some form of predator/prey game in which either the human attempts to catch the ferret or the ferret to catch the human. They also have a strong nesting instinct and will repeatedly carry small objects to hidden locations. It is difficult to predict what objects ferrets will attempt to hoard, with owners reporting play toys, socks, bags of onions, pizza slices, keys, calculators, silverware, aluminum foil, shoes, sponges, toilet paper rolls, textbooks, video game controllers, footballs, etc. Ferrets will seemingly form attachments to certain objects and will repeatedly 'steal' the same object and bring it to their hiding place.
Ferrets are easily entertained and do not require pet toys; however, most kitten toys work well with ferrets. Ferrets love playing tug of war with toys and stuffed animals. Ferrets will also tear open packages and other containers to see what is inside or explore the inside of the package. Ferrets are interested in holes, pipes and other small enclosed areas, and seem compelled to explore holes. Thus a cardboard or plastic tube will be appreciated. Ferrets are especially fond of variety in their toy selection - bell-balls, crinkle tubes, and paper bags will work well. All toys should be mixed up regularly, as ferrets will often grow bored of playing the same games repeatedly.
When ferrets are excited, they may perform a routine commonly referred to as the weasel war dance, a frenzied series of sideways hops. This is often accompanied by a soft clucking noise, commonly referred to as dooking. It is often an invitation to play or an expression of happy excitement and is not threatening.
The ferret's posture may become rigid with wide open jaws, momentary eye contact followed by thrashing or turning of the head from side to side, arching the back, piloerection, and hopping to the side or backwards while facing the intended playmate. This is often accompanied by an excited panting sound that may sound like a hiss. Often, this behavior will break into a game of chase, pounce and wrestle. Ferrets in war dances are very accident prone, often hopping into obstacles or tripping over their own feet.[19][20][21]
Ferrets tend to nip as kits. Nipping is the act of biting in a playful manner representative of mock fighting and sparring; young ferrets are also more prone to chewing and teething, and have a tendency to bite harder. Older ferrets tend to chew far less frequently and, when trained correctly, almost never nip a human hand or only do so very gently. However, ferrets that have been abused or are in extreme pain may bite a human, and are capable of strong bites which break through the skin.
Ferrets, like cats, can use a litter box with training, but they are not always completely litter box trainable. Their instinct is to spread their waste in order to scent mark a wider foraging territory for themselves; thus, multiple litter boxes may be necessary, and all litter areas should be changed frequently.
A common ferret problem to many pet owners is introducing new ferrets to their population. Senior ferrets may seem excessively violent to unknown ferrets in their home, but adding another ferret to ones population to decrease boredom or for breeding will greatly encourage the morale of the ferret or ferret population one owns. Males and females will exhibit much stronger territorial urges when confronted with a new ferret, and will often treat the new ferret like a toy. After a fighting period which should be monitored but only rarely results in harm to a ferret, the older ferret will show its dominance, often by dragging the junior ferret around by the scruff of the neck to its hoard and leaving it like any other object it values. Given time and careful monitoring, new ferrets will almost always be accepted by the older ferret or group. Young ferrets can actually benefit from having an older house trained ferret around when being taught to use a litter box, take baths, or have their nails clipped.
## Diet
Ferrets are obligate carnivores and the natural diet of their wild ancestors consisted of whole small prey, i.e., meat, organs, bones, skin, feathers, and fur. Some ferret owners feed a meat-based diet consisting of whole prey like mice and rabbits along with raw meat like chicken, beef, veal, kangaroo and wallaby. This is preferred in Europe and Australia, and becoming increasingly popular in the United States due to concern over high carbohydrate levels in some processed ferret foods.[22]
Alternatively, there are many commercial ferret food products. Some kitten foods can also be used, so long as they provide the high protein and fat content required by the ferret's metabolism. Most adult cat foods and kitten foods are unsuitable for ferrets however, because of their low protein content and high fiber. Ideally, a ferret food should contain a minimum of 32% meat based protein and 18% fat.[23] Low-quality pet foods often contain grain-based proteins, which ferrets cannot properly digest.
Ferrets may have a fondness for sweets like raisins, bananas, peanut butter, and pieces of cereal. The high sugar content of such treats has been linked to ferret insulinoma and other diseases. Veterinarians recommend not feeding raisins and the like to ferrets at all. Also, like many other carnivores, ferrets gradually lose the ability to digest lactose after they are weaned. As a result, lactose-free milk is to be preferred.
Many ferrets are sold very young. Sometimes a ferret will be sold too young; after consultation with a veterinarian, it should be fed a mix of crushed or soft food mixed with milk slightly warmed, until the veterinarian advises otherwise.
## Dangers to ferrets
Ferret curiosity often exceeds common sense and ferrets are good at getting into holes in walls, doors, cupboards, or in or behind household appliances such as clothes dryers and dishwashers, where they can be injured or killed by drowning, electrical wiring, fans, and other household items. Many enjoy chewing items made of soft rubber, foam, or sponge, which present the risk of intestinal blockage and death if ingested. Serious and sometimes fatal injuries have resulted from ferrets chewing on electrical cords. Screen doors can be damaged by a ferret's claws, and dryer vents often become escape routes to the outdoors.
Unlike dogs and cats, many ferrets display little homing instinct and do not thrive as strays. Ferret owners frequently train ferrets at a young age to respond to clicker toys, or to the sound of their own food being shaken, as a means of recovering a ferret which has ventured too far from its home. In all cases, the escape of a ferret should be addressed immediately, as wandering ferrets may be easily injured or killed by neighborhood animals, local wildlife, or passing vehicles.
Recliners and fold-out sofas are a leading cause of accidental death in ferrets.[24] Ferrets will often climb inside the springs and can be injured or killed once the chair is put into a reclined position.
For these reasons, owners usually "ferret-proof" their home, the task of carefully going through each room, removing items dangerous to ferrets and covering over any holes or potential escape routes. As ferrets can open improperly latched cupboards or doors by rolling over and clawing at the bottom edge, childproof latches are often used and owners keep cleaning products in high, out-of-reach places. However, ferrets can typically fit through any hole as small as the size of their head, making some childproof latches ineffective.
Some owners may prefer to house their pets outdoors in sheds, and not indoors. This is becoming more popular, due to speculation on the possible effects of the photoperiod effect on the ferret adrenal gland.[25]
When a ferret is outdoors, an owner must take additional care during mosquito and tick season, as ferrets are susceptible to the diseases carried by these parasites. Ticks can attach themselves and begin to draw blood. When the tick gets full, it regurgitates some blood and tick saliva back into the ferret, which is how Lyme and other diseases can be transmitted. Ordinarily, the regurgitation happens between five to 24 hours after the tick attaches. Early removal of ticks using proper methods to avoid tick regurgitation, and prevention when in environments where encountering ticks is essential. Additionally, mosquitoes may carry heart worms and the West Nile virus. Fleas can cause extreme skin irritation and can be intermediate hosts for tapeworms, one of which may kill a ferret because of their small size. Similarly, the venom of a bee, wasp or spider is much more serious for a ferret than for a larger mammal, and ferrets can be regarded as prey by hawks, and by large snakes.
Ferrets are fearless to the point of foolishness and should not be allowed to wander. Whenever they are outside, they should be closely supervised and preferably kept on a harness leash designed for ferrets such as an H-shaped harness. Their curious nature also leads them to place themselves in situations where they will confront and try to play with larger animals outdoors that may be dangerous to the ferret.
Ferrets have been known to play well with household cats and some non-aggressive dogs, however, great care must be taken when introducing ferrets to any other household pets. Certain terrier dog breeds even have a heightened instinct to grab and kill ferrets. Many breeders these days prefer to raise their young kits with prey animal (baby & adult mouse, chicken, hamster, rats etc) instead of giving dry food. Therefore, ferrets may attack and kill pets like rodents, birds, and small reptiles, which may have been the prey of their wild ancestors.
## Ferrets and children
Ferrets can make good pets for some children, but usually do not make good pets for very young children. Important considerations include assessing potential danger to a human child by a pet ferret, and potential danger to a pet ferret by a human child, either deliberately or by neglect.
Ferrets are capable of delivering a bite almost as strong as a domestic cat. Like all other domesticated animals, they should never be left unsupervised near infants or very young children. There have been rare cases where ferrets have severely injured babies but nearly all such incidents involved neglect, abuse, or roughhousing that the ferret likely perceived as an attack, and some of the animals involved were ferret-polecat hybrid crosses.[26] Given that young children and ferrets can be both excitable and prone to rough play, interaction between ferrets and children must always be closely supervised for the protection of both.
With regard to the danger of potential pet ferret attacks as contrasted to attacks from other pet species, statistics would imply that the danger is probably overstated. In the United States, a government study by the California Department of Health Services on national pet attack statistics found 452 reported incidents of ferret bites during the ten year period 1978-1987.[27][28] By comparison, pet dogs accounted for an estimated 585,000 injuries that required medical attention in the year 1986 alone,[29] with the total number of pet dogs in the United States in 1996 estimated at 55,000,000[30] and the total number of pet ferrets in the United States in 1996 estimated at 800,000.[31] Adjusting for the proportionate ratio of dogs to ferrets in the United States of 68 to 1, dog bites occurred 190 times more often than ferret bites.
As the possible danger to a human child by a pet ferret must be assessed, the possible danger to a pet ferret by a human child should also be considered in determining whether or not a ferret will make a good pet for a child. Younger children may play too rough with a ferret, or fail to anticipate the physical danger to a ferret from things like closing doors, heavy objects, or accidentally stepping on the animal during play, all of which may lead to severe injury, and often the need for surgery, for the ferret involved. Repeated rough play may psychologically and physically stress the ferret and increases the likelihood of a provocation and a defensive response or bite from the animal. Additionally, as with any pet, young children may fail to appreciate the responsibilities of care and maintenance of their ferret, including attention to proper food and water supply, cage and litter maintenance, grooming, and the need for daily activity and attention when the ferret is alert and active. If a parent or responsible party is not present and willing to step in and fulfill these needs, a ferret is likely a poor choice of pet for a child, due to the problem of neglect.
For children who demonstrate responsible behavior, in regard to both playing with their pet and to consistent care and maintenance, ferrets can make good pets and are often loved by children for their social personalities and engaging antics.
## Other uses of ferrets
Ferrets have been used to run wires and cables through large conduits. Event organizers in London used ferrets to run TV and sound cables for both the wedding of Charles, Prince of Wales to Lady Diana Spencer, and for the "Party in the Park" concert held in Greenwich Park on Millennium Eve.[32] One ferret, Freddie, was even registered as an electrician's assistant with the New Zealand Electrical Workers Union.[33]
Because they share many anatomical and physiological features with humans, ferrets are extensively used as experimental subjects in biomedical research, in fields such as virology, reproductive physiology, anatomy, endocrinology and neuroscience.
### Ferrets' role in prescription medication disposal
SAMHSA spokesman Mark Weber listed ferret waste as an alternative to using coffee grinds for the safe disposal of prescription medicine. This method has dual purpose: to keep prescription medications from being abused, and to minimize the effect on fish and amphibians from medications flushed down the toilet.[34]
# Ferret biology and health concerns
Ferrets do not require frequent bathing, which may remove natural oils in the ferrets coat that prevent dry skin. However, most ferrets are not averse to water. Ferrets also need their nails clipped on a regular basis, and usually shed twice a year in the spring and fall. A laxative is sometimes administered, to help any ingested fur pass more easily through the digestive tract.
Ferret bedding should be washed or changed regularly, and the litter box cleaned frequently, which significantly lessens any unpleasant odors. Due to their low carriage and their sensitive mucous membranes, ferrets are extremely sensitive to dust in their environment and many cat litters may be unsuitable for them. Also, a clumping cat litter may be ingested and cause blockages. A litter made from recycled paper material or organic material (e.g. corn or wheat) is preferred.
Most veterinarians recommend an annual health checkup. Ferrets often hide symptoms of illness very well, so any unusual behavior is considered good cause for a medical consultation. As ferrets have high metabolisms and cancers can progress at a fast rate, early detection is critical for successful treatment.
Like many other carnivores, ferrets have scent glands near their anuses, the secretions from which are used in scent marking. It has been reported that ferrets can recognize individuals from these anal gland secretions, as well as the sex of unfamiliar individuals.[35] Ferrets may also use urine marking for sex and individual recognitions.[36]
Like skunks, ferrets can release their anal gland secretions when startled or scared, but the smell dissipates rapidly. Most pet ferrets in the US are sold de-scented, with their anal glands removed. In the UK, many consider de-scenting an unnecessary mutilation. In Australia and the UK, the general opinion is that the animal does not need to be de-scented. The Netherlands and other parts of Europe consider this practice to be animal abuse.
Males, if not neutered, are extremely musky. It is considered preferable to delay neutering until sexual maturity has been reached, at approximately 6-8 months old, after the full descent of the testicles. Neutering the male will reduce the smell to almost nothing. The same applies for females, but spaying them is also important for their own health. Unless they are going to be used for breeding purposes, female ferrets will go into extended heat and an unbred female without medical intervention can die of aplastic anemia.
Many domestic ferrets are known to suffer from several distinct health problems. Among the most common are cancers affecting the adrenal glands, pancreas, and lymphatic system. Some health problems have been linked to ferrets being neutered before sexual maturity was reached, because of this some owners now choose to use implants instead of having the ferret neutered too early. Some owners even choose not to have their ferret neutered at all but use longer working implants instead. Certain colors of ferret may also carry a genetic defect known as Waardenburg syndrome .
Many of the diseases present in ferrets can cause severe weight loss, which, due to their size, can be an even more extreme problem than in some other animals. Ferrets suffering from extreme weight loss or with sensitive digestive tracts are often recommended to be fed a mixture called "duck soup." This usually contains a high-fat, high-protein, low-fiber mixture of a whole chicken (innards and all), fat drippings, Nutrical, Ferretone, high-grade kitten food, and several other ingredients, variant on recipe. "Duck soup" helps ensure that a ferret keeps his or her weight up and is easy on the intestines.
Dehydrated ferrets may also be given Pedialyte.
## Adrenal disease
Adrenal disease, a growth of the adrenal glands that can be either hyperplasia or cancer, is most often diagnosed by signs like unusual hair loss, increased aggression, difficulty urinating or defecating, or agitation when urinating, and (in the case of females) an enlarged vulva. Even if the growth is benign, it can still cause a hormonal imbalance which can have devastating effects on the ferret's health.
Treatment options include surgery to excise the affected glands, melatonin implants, which treat the symptoms but not the disease itself, and/or hormone therapy. The causes of adrenal disease are as yet uncertain, but speculated triggers include unnatural light cycles, diets based around processed ferret foods, and prepuberty neutering. It has also been suggested that there may be a hereditary component to adrenal disease.[37]
Adrenal disease is usually detected during the spring or fall. This is because adrenal disease affects the hormones that make the fur grow, so when ferrets with adrenal disease shed their winter coat they simply don't grow it back because of the disease. The hair loss pattern is usually very specific for adrenal disease: It begins at the base of the tail and then continues up the ferret's back. Ferrets who have been treated for adrenal disease may also suffer temporary but severe hair loss as their bodies recover.
## Insulinoma
Ferrets are also known to suffer from insulinoma, a cancer of the pancreas. The growth of cancerous nodules on the lobes of the pancreas sometimes, but not always, leads to an increase in the production of insulin, which regulates the rate at which the ferret's body metabolizes blood glucose. Too much insulin will cause blood sugar to drop, resulting in lethargy, seizures, and ultimately death. Symptoms of an insulinoma attack include episodes of lethargy, drooling, pawing and/or foaming at the mouth, high pitched screams, staring "blankly" into space, and seizures.
Like adrenal cancer, the exact cause of insulinoma is unknown. It is speculated that the diets of domestic ferrets are too far removed from the natural diets of their polecat ancestors, and include too much sugar or simple carbohydrates.
Treatment for insulinoma may include surgical excision of the cancerous lobes, pharmaceutical treatment with steroids that suppress the production of insulin, supplemental changes in diet (most often poultry-based baby food), or a combination thereof. Unfortunately, the growth of the tumors cannot be completely stopped, and the ferret will eventually suffer a recurrence of symptoms. In an insulinoma attack, a temporary remedy to stabilize the ferret is any kind of a sugary syrup, such as corn syrup or honey.
## Lymphoma
Lymphoma/lymphosarcoma is the most common malignancy in ferrets. Ferret lymphosarcoma occurs in two forms -- juvenile lymphosarcoma, a fast-growing type that affects ferrets younger than two years, and adult lymphosarcoma, a slower growing form that affects ferrets four to seven years old.
In juvenile ferret lymphosarcoma, large, immature lymphocytes (lymphoblasts) rapidly invade the thymus and/or the organs of the abdominal cavity, particularly the liver and spleen. In adult ferret lymphosarcoma, the lymph nodes in the limbs and abdominal cavity become swollen early on due to invasion by small, mature lymphocytes. Invasion of organs, such as the liver, kidney, lungs, and spleen, occurs later on, and the disease may be far advanced before symptoms are noticeable.
As in humans, ferret lymphosarcoma can be treated surgically, with radiation therapy, chemotherapy or a combination thereof. The long-term prognosis is rarely bright, however, and this treatment is intended to improve quality of life with the disease.
## Viral diseases
Epizootic catarrhal enteritis (ECE)
ECE, a viral disease that first appeared in the northeastern US in 1994, is an inflammation of the mucous membranes in the intestine. The disease manifests itself as severe diarrhea (often of a bright green color), loss of appetite, and severe weight loss. The virus can be passed via fluids and indirectly between humans. Although it was often fatal when first discovered, ECE is less of a threat nowadays with the right supportive care which usually includes hospitalization with intravenous fluids. The virus is especially threatening to older ferrets and requires immediate attention.
Aleutian disease virus (ADV)
Aleutian Disease Virus (ADV) is a parvovirus discovered among mink in the Aleutian Islands in the early 20th century. In ferrets, the virus affects the immune system (causing it to produce non-neutralizing antibodies) and many internal organs, particularly the kidneys. There is no cure or vaccine for the disease, and ferrets may carry the virus for months or years without any external symptoms. As a result, some ferret organizations and shelters recommend that owners test their pets for the virus regularly, separating them from other ferrets if they test positive.
Canine distemper
Canine distemper (CD) is an extremely contagious virus that is almost always fatal. Being strict indoor pets does not necessarily protect ferrets, as owners may bring the virus home on their clothes or their shoes. The only protection against the virus is vaccination, but that is not without controversy as there have been reports, particularly from the USA, of ferrets going into anaphylactic shock after being vaccinated against CD.
Influenza virus isolation using ferrets
Ferrets have served as a good experimental animal models in the study of influenza virus. Smith, Andrews, Laidlaw(1933)inoculated ferrets intra-nasally with human naso-pharyngeal washes, which produced a form of influenza that spread to other cage mates. The human influenza virus(Influenza type A) was transmitted from an infected ferret to a junior investigator , from whom it was subsequently re-isolated.
## Waardenburg-like coloring
Ferrets with a white stripe on their face or a fully white head, primarily blazes, badgers, and pandas, almost certainly carry a congenital defect which shares some similarities to Waardenburg syndrome. This causes, among other things, a cranial deformation in the womb which broadens the skull, causing the white face markings but also partial or total deafness. It is estimated as many as 75% of ferrets with these Waardenburg-like colorings are deaf. Beyond that, the cranial deformation also causes a higher instance of stillborn ferret kits, and occasionally cleft palates. Because of this, many breeders will not breed Waardenburg-patterned ferrets.
# Terminology and coloring
Male intact ferrets are called hobs; female intact ferrets are jills. A spayed female is a sprite, and a neutered male is a gib. Ferrets under one year old are known as kits. A group of ferrets is known as a business.
Ferrets come in a variety of coat colors and patterns. The ones recognized by the American Ferret Association are as follows:[39]
White ferrets were favored in the Middle Ages for the ease in seeing them in thick undergrowth. Leonardo's painting Lady with an Ermine is likely mislabeled; the animal is probably a ferret, not a stoat, for which "ermine" is an alternative name (the latter strictly applying only to the animal in its white winter coat). Similarly, the Ermine portrait of Queen Elizabeth the First shows her with her pet ferret, who has been decorated with painted-on heraldic ermine spots.
"The Ferreter's Tapestry" is a fifteenth-century tapestry from Burgundy, France now part of the Burrell Collection housed in the Glasgow Museum and Art Galleries. It shows a group of peasants hunting rabbits with nets and white ferrets.
"Pope Celestinus III Grants Privilege of Independence to the Spedale" painted by Domenico di Bartolo in 1443 shows a fashionable man with a colored pet ferret wearing a red collar on his shoulder. This image was reproduced in Renaissance Dress In Italy 1400-1500, by Jacqueline Herald, Bell & Hyman - ISBN 0-391-02362-4
Gaston Phoebus' Book Of The Hunt was written in approximately 1389 to explain how to hunt different kinds of animals, including how to use ferrets to hunt rabbits. Illustrations show how multicolored ferrets that are fitted with muzzles were used to chase rabbits out of their dens and into waiting nets.
# Ferrets featured in literature and culture
- In the 1984 made-for-TV movie Caravan of Courage: An Ewok Adventure, the main character Cindel plays with Wicket's pet ferret in a scene shortly after their "star cruiser" crashed.
- The Greek playwright Aristophanes made reference to ferrets in his satire The Acharneans written around the year 425 BC. "What a happy man he’ll be that marries you and begets a set of Ferrets as good as you at farting in the Grey dawn!".
- The main character in the Japanese manga series Peach Fuzz is a ferret named Peach who has delusions of being a princess.
- The title character of the short story Sredni Vashtar by Edwardian satirist Saki is a "polecat-ferret" clandestinely kept by a young boy, who is liberated when the animal he worships as a god kills his overbearing guardian.
- The children's book Zucchini by Barbara Dana is about a boy and his pet ferret. However, the author gets a number of basic ferret facts wrong, claiming that they are vegetarian rodents.
- Former Doctor Who lead actor Sylvester McCoy got his acting start as Sylvester McCoy, the Human Bomb, a stage act that consisted of stuffing live ferrets down his trousers.[citation needed]
- In the film The Big Lebowski, Lebowski is attacked in the bathroom by a "Marmot" which is really a ferret.
- In the film Kindergarten Cop, John Kimble (played by Arnold Schwarzenegger) owns a pet ferret, which becomes the mascot of his kindergarten class and saves his life by biting the main antagonist near the end of the film.
- In the film Starship Troopers, Colonel Carl Jenkins (played by Neil Patrick Harris) owns a pet ferret, which he mischievously tells (via Telepathy) to go and find a treat up his mother's leg.
- Richard Bach, author of Jonathan Livingston Seagull, has written five books starring ferrets, the Ferret Chronicles series.
- In the 2004 romantic comedy Along Came Polly, Jennifer Aniston's character, Polly, owns a blind ferret who often runs head-first into stationary objects, to great comic effect. The ferret is featured in the promotional material for the film.
- The film and TV series The Beastmaster has two ferrets, Kodo & Podo, which appear as major characters. The series' protagonist usually kept them in a small pouch attached to his belt.
- In the fourth Harry Potter book and film, Harry Potter and the Goblet of Fire, the character Draco Malfoy is turned into an albino ferret.
- The BBC children's television magazine program Xchange featured the puppet Vinnie, a mischievous ferret.
- HTV Wales has a long-running investigation series called The Ferret.
- Ferrets are the obvious suspects in the mystery novel "Nothing to Fear but Ferrets" by Linda O. Johnston.
- Budweiser (Anheuser-Busch) has used a fictitious ferret in a series of radio commercials.
- Bill Owen's character Compo in the BBC series Last of The Summer Wine (1973) had two ferrets which caused an uproar at a funeral in one episode.
- Japanese Media: Ferrets have appeared in the manga Ask the Stars for Help ( 困った時には星に聞け! ) by Miyuki Abe ( あべ 美幸 ) and in the anime series Nanoha ( なのは ) - "In a failed attempt to seal a seed properly, he winds up on Earth in the form of a ferret." The character Yūno Scrya has an animal form as a ferret.
- The popular webcomic, Sluggy Freelance has a main character named Kiki who is a ferret.
- A ferret called Fungo Squiggly is one of the supporting characters in the Get Fuzzy comic strip by Darby Conley.
- In Degrassi: The Next Generation Ellie Nash owns a ferret name Bueller for a short time until he dies due to chewing on electrical wires.
- In the Pokémon series, the pokemon called Furret is based on a ferret.
- There are numerous ferrets in the Redwall series by Brian Jacques.
- Paris Hilton once owned a ferret. She walked the red carpet with it many times, and was publicly scrutinized for taking the ferret, as well as several other animals, to social events.
- On Tucker Carlson Live, Rudy Giuliani tells a man who called in asking why he banned ferrets in New York City that "The excessive concern that you have for ferrets is a sickness that you should examine with a therapist."
- In the cartoon series The Littles, Dr. Hunter had a ferret which he often used to try to capture the Littles.
- In a commercial for Diet Mountain Dew, a ferret walks through the woods with a hockey mask and a chainsaw, chasing two teens.
- The character Bandit is a ferret on the webcomic The Whiteboard.
- The 1st Battalion, the Yorkshire Regiment of the British Armed Forces, keeps two ferrets, Imphal and Quebec, as its unofficial mascots, named after the battalion's battle honors.[40]
- In the manga and anime Strawberry Marshmallow (苺ましまろ, Ichigo Mashimaro) by Barasui, the character Matsuri Sakuragi owns a pet ferret named John.
- In the manga Ai Yori Aoshi by Kou Fumizuki, Miyabi Kagurazaki acts as the main caretaker of an explorative albino ferret named Uzume.
- In the anime and manga Infinite Ryvius, the character Fina owns a ferret named Rafra.
- In the Babymouse series, Babymouse's Best friend is a ferret named Wilson
- The children's book Poggin Tails by Nick Cooper is a collection of short stories featuring Poggin, a polecat.
- In the animated children's series Iggy Arbuckle, the characters Robear and Robert are ferrets.
- In the TV show Ned's Declassified School Survival Guide, Gordy is always over-elaborately hunting a "weasel" which is really a stuffed ferret.
- In the 2007 film The Golden Compass, the daemon Pantalaimon spends much of the film as a ferret-like animal.
- In the 2007 film Stardust, the witch Empusa is attacked and devoured by ferrets and wolves.
- French poet Jean Follain wrote the 75-word poem "Death of the Ferret".[41]
- In the, as yet unreleased, movie, Inkheart, based on the book by Cornelia Funke, one of the main characters, the fire-eater, Dustfinger, owns a pet marten, Gwin, which is replaced in the film by a 'polecat' or sable ferret.
# Regulation on ferrets as pets
- Australia It is illegal to keep ferrets as pets in Queensland or the Northern Territory; in the ACT a license is required.
- Brazil Ferrets are becoming popular. They are only allowed if they are given a microchip identification tag and sterilized.
- Iceland Selling, distributing, breeding and keeping ferrets is illegal in Iceland.
- New Zealand It has been illegal to sell, distribute or breed ferrets in New Zealand since 2002.
- Portugal It is illegal to keep ferrets as pets in Portugal. Ferrets can only be used for hunting purposes and can only be kept with a government permit.
- United States Ferrets were once banned in many US states, but most of these laws were rescinded in the 1980s and 90s as they became popular pets. Ferrets are still illegal in California under Fish and Game Code Section 2118[42] and the California Code of Regulations.[43] Additionally, "Ferrets are strictly prohibited as pets under Hawaii law because they are potential carriers of the rabies virus";[44] the territory of Puerto Rico has a similar law.[45] Ferrets are also restricted by individual cities, such as, Washington, DC and New York City.[45] They are also prohibited on many military bases.[45] A permit to own a ferret is needed in other areas, including Rhode Island.[46] Illinois and Georgia do not require a permit to merely possess a ferret, but a permit is required to breed ferrets.[47] [48] It was once illegal to own ferrets in Dallas, Texas,[49] but the current Dallas City Code for Animals includes regulations for the vaccination of ferrets.[50]
## Travel regulations
### Airline policies
Most airlines require advance booking for ferret travel, and may levy additional fees. Requirements concerning pet carrier size, weight, and construction may vary from airline to airline. In the U.S., Delta Airlines is the only airline to allow ferrets in the cabin during a flight.
### Train policies
### Import laws
Ferrets are legal in most US states except, California, and Hawaii [59].
Ferrets cannot be imported into Australia at all. A report drafted in August 2000 seems to be the only effort made to date to change the situation.[60]
Ferrets brought from anywhere except the US require a Permit to Import from the Canadian Food Inspection Agency Animal Health Office. Ferrets from the US require only a vaccination certificate signed by a veterinarian. Ferrets under three months old are not subject to any restrictions for importation.[61]
As of July 2004, dogs, cats, and ferrets can travel freely within the European Union under the PETS travel scheme. To cross a border within the EU, ferrets require at minimum an EU PETS passport and an identification microchip (though some countries will accept a tattoo instead). Vaccinations are also required; most countries require a rabies vaccine, and some also require a distemper vaccine and treatment for ticks and fleas 24 to 48 hours before entry. PETS travel information is available from any EU veterinarian or on government websites.
Although previously pet ferrets were allowed to be brought into Japan, that is no longer the case. Individual pet ferrets cannot be brought into Japan without proper documents. However, licensed breeders such as Canadian Farms, PVF, Marshall's, etc... have a special agreement that still allows the import of those ferrets from those companies.
The UK accepts ferrets under the PETS travel scheme. Ferrets must be microchipped, vaccinated against rabies, and documented. They must be treated for ticks and tapeworms 24 to 48 hours before entry. They must also arrive via an authorized route. Ferrets arriving from outside the EU may be subject to a six-month quarantine.[62] | https://www.wikidoc.org/index.php/Ferret | |
852f2ea518541e644acc57a08cb3ebe8dd437981 | wikidoc | Ferula | Ferula
# Overview
Ferula (from Latin ferula, "rod") is a genus of about 170 species of flowering plants in the family Apiaceae, native to the Mediterranean region east to central Asia, mostly growing in arid climates. They are herbaceous perennial plants growing to 1–4 m tall, with stout, hollow, somewhat succulent stems. The leaves are tripinnate or even more finely divided, with a stout basal sheath clasping the stem. The flowers are yellow, produced in large umbels. Many plants of this genus, especially F. communis are referred to as "giant fennel," although they are not fennel in the strict sense.
# Selected species
- Ferula assafoetida - Asafoetida
- Ferula caspica
- Ferula communis - Giant fennel
- Ferula conocaula
- Ferula diversivittata
- Ferula foetida
- Ferula gummosa, syn. galbaniflua - Galbanum
- Ferula hermonis
- Ferula karelinii
- Ferula linkii
- Ferula longifolia
- Ferula marmarica
- Ferula moschata, syn. sumbul - Muskroot
- Ferula narthex - Ferula
- Ferula orientalis
- Ferula persica
- Ferula schair
- Ferula szowitziana
- Ferula tingitiana
- The Roman spice silphium probably came from a now extinct species of Ferula.
# Uses
The gummy resin of many species of Ferula is used for medical or culinary purposes:
The Romans called the hollow light rod made from this plant a ferula (compare also fasces, judicial birches). Such rods were used for walking sticks, splints, for stirring boiling liquids, and for corporal punishment.
The ferula also shows up in mythological contexts. The main shaft of a thyrsus was traditionally made from this plant, and Prometheus smuggled fire to humanity by hiding it in a ferula as well.
Women in Central Asia as well as a small number in the Appalachian mountains of North Carolina use these to induce abortion in first trimester.
co:Ferula (genaru)
de:Steckenkräuter
it:Ferula (genere)
la:Ferula (genus)
zh-yue:阿魏 | Ferula
# Overview
Ferula (from Latin ferula, "rod") is a genus of about 170 species of flowering plants in the family Apiaceae, native to the Mediterranean region east to central Asia, mostly growing in arid climates. They are herbaceous perennial plants growing to 1–4 m tall, with stout, hollow, somewhat succulent stems. The leaves are tripinnate or even more finely divided, with a stout basal sheath clasping the stem. The flowers are yellow, produced in large umbels. Many plants of this genus, especially F. communis are referred to as "giant fennel," although they are not fennel in the strict sense.
# Selected species
- Ferula assafoetida - Asafoetida
- Ferula caspica
- Ferula communis - Giant fennel
- Ferula conocaula
- Ferula diversivittata
- Ferula foetida
- Ferula gummosa, syn. galbaniflua - Galbanum
- Ferula hermonis
- Ferula karelinii
- Ferula linkii
- Ferula longifolia
- Ferula marmarica
- Ferula moschata, syn. sumbul - Muskroot
- Ferula narthex - Ferula
- Ferula orientalis
- Ferula persica
- Ferula schair
- Ferula szowitziana
- Ferula tingitiana
- The Roman spice silphium probably came from a now extinct species of Ferula.
# Uses
The gummy resin of many species of Ferula is used for medical or culinary purposes:
The Romans called the hollow light rod made from this plant a ferula (compare also fasces, judicial birches). Such rods were used for walking sticks, splints, for stirring boiling liquids, and for corporal punishment.
The ferula also shows up in mythological contexts. The main shaft of a thyrsus was traditionally made from this plant, and Prometheus smuggled fire to humanity by hiding it in a ferula as well.
Women in Central Asia as well as a small number in the Appalachian mountains of North Carolina use these to induce abortion in first trimester.
co:Ferula (genaru)
de:Steckenkräuter
it:Ferula (genere)
la:Ferula (genus)
zh-yue:阿魏
Template:WH
Template:WS | https://www.wikidoc.org/index.php/Ferula | |
bfe06c8bd172bac2862dc7e3e622397d00bfcbe4 | wikidoc | Fetuin | Fetuin
Fetuins are blood proteins that are made in the liver and secreted into the bloodstream. They belong to a large group of binding proteins mediating the transport and availability of a wide variety of cargo substances in the bloodstream. Fetuin-A is a major carrier protein of free fatty acids in the circulation. The best known representative of carrier proteins is serum albumin, the most abundant protein in the blood plasma of adult animals. Fetuin is more abundant in fetal blood, hence the name "fetuin" (from Latin, fetus). Fetal bovine serum contains more fetuin than albumin, while adult serum contains more albumin than fetuin.
# Family members
Human fetuin is synonymous with α2-HS-glycoprotein (genetic symbol AHSG), α2-HS, A2HS, AHS, HSGA, and fetuin-A. Fetuin-A exists as a single-copy gene in the human and mouse genomes. A closely related gene, fetuin-B, also exists in the human, rat, and mouse genomes. Like fetuin-A, fetuin-B is made predominantly by the liver and to a lesser extent by a number of secretory tissues. Fetuins exist in all vertebrate genomes including fish and reptiles. Fetuins are members of a family of proteins that evolved from the protein cystatin by gene duplication and exchange of gene segments. Fetuins thus belong to the cystatin superfamily of proteins. Fetuin relatives within this superfamily are the histidine-rich glycoprotein (HRG) and kininogen (KNG).
# Animal studies
The function of Fetuin-A in the body was determined by gene knockout technology in mice. Knocking out the gene for fetuin-A rendered the mice completely fetuin-A deficient. Feeding a mineral-rich diet to fetuin-A-deficient mice resulted in widespread calcification (ectopic mineralization) of lung, heart, and kidneys in these mice. The calcification became drastically exacerbated when the fetuin-A knockout was combined with the genetic background DBA/2. The mouse strain DBA/2 is known for its proneness to calcify damaged tissues, a process called "dystrophic calcification". Fetuin-A deficiency dramatically increased the calcification proneness of these mice in that all mice spontaneously calcified throughout their body even without a mineral-rich diet or surgical tissue trauma. Fetuin-A is therefore regarded as a potent inhibitor of systemic calcification.
Free fatty acids cause Fetuin-A overexpression by increasing the pro-inflammatory protein NF-κB. Fetuin-A has been shown to facilitate the binding of free fatty acids to TLR4 receptors, thereby inducing insulin resistance in mice.
# Human studies
Fetuin-A was originally discovered to be an inhibitor of vascular calcification in early 1990s. Since then the biologic roles attributed to fetuin-A have increased exponentially. Fetuin-A has been demonstrated to play an important role in free fatty acid induced insulin resistance in the liver. Increased fetuin-A in patients with pre-diabetes is associated with increased progression to diabetes and decreased reversal to normoglycemia. Hence fetuin-A is a predictor of adverse glycemic outcomes in pre-diabetes. Obese persons have elevated circulating Fetuin-A, which can be reduced by metformin, exercise, or weight loss. Increased fetuin-A had been also been linked to increased occurrence of non-alcoholic fatty liver disease and cardiovascular events, believed to be due to its proinflammatory effects.
Fetuin-A in contrast has also been demonstrated to have anti-inflammatory properties. It is a negative acute-phase reactant in sepsis and endotoxemia, promotes wound healing, and is neuroprotective in Alzheimer's disease. Decreased fetuin-A is a predictor of increased disease activity in obstructive lung disease, Crohn's disease, and ulcerative colitis. Differential effects on different toll like receptors in different tissues and organ systems may explain these paradoxical effects in different systems. | Fetuin
Fetuins are blood proteins that are made in the liver and secreted into the bloodstream. They belong to a large group of binding proteins mediating the transport and availability of a wide variety of cargo substances in the bloodstream.[1] Fetuin-A is a major carrier protein of free fatty acids in the circulation.[1] The best known representative of carrier proteins is serum albumin,[citation needed] the most abundant protein in the blood plasma of adult animals. Fetuin is more abundant in fetal blood, hence the name "fetuin" (from Latin, fetus). Fetal bovine serum contains more fetuin than albumin, while adult serum contains more albumin than fetuin.
# Family members
Human fetuin is synonymous with α2-HS-glycoprotein (genetic symbol AHSG), α2-HS, A2HS, AHS, HSGA, and fetuin-A. Fetuin-A exists as a single-copy gene in the human and mouse genomes. A closely related gene, fetuin-B, also exists in the human, rat, and mouse genomes. Like fetuin-A, fetuin-B is made predominantly by the liver and to a lesser extent by a number of secretory tissues. Fetuins exist in all vertebrate genomes including fish and reptiles. Fetuins are members of a family of proteins that evolved from the protein cystatin by gene duplication and exchange of gene segments. Fetuins thus belong to the cystatin superfamily of proteins. Fetuin relatives within this superfamily are the histidine-rich glycoprotein (HRG) and kininogen (KNG).
# Animal studies
The function of Fetuin-A in the body was determined by gene knockout technology in mice. Knocking out the gene for fetuin-A rendered the mice completely fetuin-A deficient. Feeding a mineral-rich diet to fetuin-A-deficient mice resulted in widespread calcification (ectopic mineralization) of lung, heart, and kidneys in these mice. The calcification became drastically exacerbated when the fetuin-A knockout was combined with the genetic background DBA/2. The mouse strain DBA/2 is known for its proneness to calcify damaged tissues, a process called "dystrophic calcification". Fetuin-A deficiency dramatically increased the calcification proneness of these mice in that all mice spontaneously calcified throughout their body even without a mineral-rich diet or surgical tissue trauma. Fetuin-A is therefore regarded as a potent inhibitor of systemic calcification.
Free fatty acids cause Fetuin-A overexpression by increasing the pro-inflammatory protein NF-κB.[1] Fetuin-A has been shown to facilitate the binding of free fatty acids to TLR4 receptors, thereby inducing insulin resistance in mice.[1]
# Human studies
Fetuin-A was originally discovered to be an inhibitor of vascular calcification in early 1990s. Since then the biologic roles attributed to fetuin-A have increased exponentially. Fetuin-A has been demonstrated to play an important role in free fatty acid induced insulin resistance in the liver. Increased fetuin-A in patients with pre-diabetes is associated with increased progression to diabetes and decreased reversal to normoglycemia. Hence fetuin-A is a predictor of adverse glycemic outcomes in pre-diabetes.[2][unreliable medical source] Obese persons have elevated circulating Fetuin-A, which can be reduced by metformin, exercise, or weight loss. [3] Increased fetuin-A had been also been linked to increased occurrence of non-alcoholic fatty liver disease and cardiovascular events, believed to be due to its proinflammatory effects.[4]
Fetuin-A in contrast has also been demonstrated to have anti-inflammatory properties. It is a negative acute-phase reactant in sepsis and endotoxemia, promotes wound healing, and is neuroprotective in Alzheimer's disease. Decreased fetuin-A is a predictor of increased disease activity in obstructive lung disease, Crohn's disease, and ulcerative colitis. Differential effects on different toll like receptors in different tissues and organ systems may explain these paradoxical effects in different systems.[5][unreliable medical source] | https://www.wikidoc.org/index.php/Fetuin | |
97465bb76f52db6042bc8e75f4a89be6e4d32ab2 | wikidoc | Fibrin | Fibrin
# Overview
Fibrin is a protein involved in the clotting of blood. It is a fibrillar protein that is polymerised to form a "mesh" that forms a hemostatic plug or clot (in conjunction with platelets) over a wound site.
Fibrin is made from its zymogen fibrinogen, a soluble plasma glycoprotein that is synthesised by the liver. Processes in the coagulation cascade activate the zymogen prothrombin to the serine protease thrombin, which is responsible for converting fibrinogen into fibrin. Fibrin is then cross linked by factor XIII to form a clot.
# Physiology
Fibrinogen (also called factor I) is a 340 kDa glycoprotein synthesised in the liver hepatocytes and megakaryocytes, which normally has a concentration between 1.5 - 4.0 g/L (normally measured using the Clauss method) in blood plasma. Therefore the concentration in plasma is about 7 µM. In its natural form, fibrinogen is useful in forming bridges between platelets, by binding to their GpIIb/IIIa surface membrane proteins; though fibrinogen's major use is as a precursor to fibrin.
Fibrinogen, the principal protein of vertebrate blood clotting is an hexamer containing two sets of three different chains (α, β, and γ), linked to each other by disulfide bonds. The N-terminal sections of these three chains are evolutionary related and contain the cysteines that participate in the cross-linking of the chains. However, there is no similarity between the C-terminal part of the α chain and that of the β and γ chains. The C-terminal part of the β and γ chains forms a domain of about 270 amino-acid residues. As shown in the schematic representation this domain contains four conserved cysteines involved in two disulfide bonds. On the alpha and beta chains, there is a small peptide sequence (called a fibrinopeptide). It is these small peptides that prevent fibrinogen spontaneously forming polymers with itself.
- Fibrinogen beta and gamma chains C-terminal domain signature
# Role in disease
Excessive generation of fibrin due to activation of the coagulation cascade leads to thrombosis, while ineffective generation predisposes to hemorrhage.
Dysfunction or disease of the liver can lead to a decrease in fibrinogen production or the production of abnormal fibrinogen molecules with reduced activity (dysfibrinogenaemia). Hereditary abnormalities of fibrinogen (the gene is carried on chromosome 4) are of both quantitative and qualitative in nature and include; afibrinogenaemia, hypofibrinogenaemia, dysfibrinogenaemia, and hypodysfibrinogenaemia.
# Diagnostic use
Fibrinogen levels can be measured in venous blood. Normal levels are about 150-300 mg/dL. Higher levels are, amongst others, associated with cardiovascular disease (>460 mg/dL). It may be elevated in any form of inflammation, as it is an acute phase protein.
It is used in veterinary medicine as an inflammatory marker: in horses a level above the normal range of 1.0-4.0 g/L suggests some degree of systemic inflammatory response.
Low levels of fibrinogen can indicate a systemic activation of the clotting system, with consumption of clotting factors faster than synthesis. This excessive clotting factor consumption condition is known as Disseminated Intravascular Coagulation or "DIC." DIC can be difficult to diagnose, but a strong clue is low fibrinogen levels in the setting of prolonged clotting times (PT or PTT), in the context of acute critical illness such as sepsis or trauma. | Fibrin
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
# Overview
Fibrin is a protein involved in the clotting of blood. It is a fibrillar protein that is polymerised to form a "mesh" that forms a hemostatic plug or clot (in conjunction with platelets) over a wound site.
Fibrin is made from its zymogen fibrinogen, a soluble plasma glycoprotein that is synthesised by the liver. Processes in the coagulation cascade activate the zymogen prothrombin to the serine protease thrombin, which is responsible for converting fibrinogen into fibrin. Fibrin is then cross linked by factor XIII to form a clot.
# Physiology
Fibrinogen (also called factor I) is a 340 kDa glycoprotein synthesised in the liver hepatocytes and megakaryocytes, which normally has a concentration between 1.5 - 4.0 g/L (normally measured using the Clauss method) in blood plasma. Therefore the concentration in plasma is about 7 µM. In its natural form, fibrinogen is useful in forming bridges between platelets, by binding to their GpIIb/IIIa surface membrane proteins; though fibrinogen's major use is as a precursor to fibrin.
Fibrinogen, the principal protein of vertebrate blood clotting is an hexamer containing two sets of three different chains (α, β, and γ), linked to each other by disulfide bonds. The N-terminal sections of these three chains are evolutionary related and contain the cysteines that participate in the cross-linking of the chains. However, there is no similarity between the C-terminal part of the α chain and that of the β and γ chains. The C-terminal part of the β and γ chains forms a domain of about 270 amino-acid residues. As shown in the schematic representation this domain contains four conserved cysteines involved in two disulfide bonds. On the alpha and beta chains, there is a small peptide sequence (called a fibrinopeptide). It is these small peptides that prevent fibrinogen spontaneously forming polymers with itself.
- Fibrinogen [2] beta and gamma chains C-terminal domain signature
# Role in disease
Excessive generation of fibrin due to activation of the coagulation cascade leads to thrombosis, while ineffective generation predisposes to hemorrhage.
Dysfunction or disease of the liver can lead to a decrease in fibrinogen production or the production of abnormal fibrinogen molecules with reduced activity (dysfibrinogenaemia). Hereditary abnormalities of fibrinogen (the gene is carried on chromosome 4) are of both quantitative and qualitative in nature and include; afibrinogenaemia, hypofibrinogenaemia, dysfibrinogenaemia, and hypodysfibrinogenaemia.
# Diagnostic use
Fibrinogen levels can be measured in venous blood. Normal levels are about 150-300 mg/dL. Higher levels are, amongst others, associated with cardiovascular disease (>460 mg/dL). It may be elevated in any form of inflammation, as it is an acute phase protein.
It is used in veterinary medicine as an inflammatory marker: in horses a level above the normal range of 1.0-4.0 g/L suggests some degree of systemic inflammatory response.
Low levels of fibrinogen can indicate a systemic activation of the clotting system, with consumption of clotting factors faster than synthesis. This excessive clotting factor consumption condition is known as Disseminated Intravascular Coagulation or "DIC." DIC can be difficult to diagnose, but a strong clue is low fibrinogen levels in the setting of prolonged clotting times (PT or PTT), in the context of acute critical illness such as sepsis or trauma. | https://www.wikidoc.org/index.php/Fibrin | |
84257c439fe94ad4e85c02021c7a7924b9659ef1 | wikidoc | FlowJo | FlowJo
FlowJo is the name of a piece of software for analyzing flow cytometry data. Files produced by modern flow cytometers are written in a standard format called .fcs. Hence FlowJo will import and analyze cytometry data regardless of which FACS (Fluorescence Activated Cell Sorting) machine is
used to collect the samples. In FlowJo samples are organized in a "Workspace" window, which presents a hierarchical view of all the samples and their analyses (gates and statistics). Viewing an entire experiment in a Workspace enables you to organize and manage complex cytometry experiments while making detailed graphical reports.
Within a workspace, samples can be grouped or sorted by various attributes
such as the panel of antibodies with which they are stained, tissue type, or
patient from whom they came. When one performs an operation on a group, FlowJo performs the same
-peration on every sample belonging to that group. Thus, you can apply a
gate to a sample, copy it to a group, and that gate will be automatically placed on all samples in the group.
FlowJo's ability to automate repetitive operations
facilitates the production of statistics tables and graphical
reports when the experiment involves many samples, parameters and/or operations.
FlowJo provides tools for the creation of:
Histogram and other plot overlays
Cell cycle analysis
Calcium flux analysis
Proliferation analysis
Quantitation
Cluster identification
and backgating display.
Tree Star, Inc. began as a software company in 1989. At that time, the authors' work at Stanford University’s Information Technology department
brought them into contact with the Herzenberg Laboratory where modern
flow cytometry originated. As the utility and power of cytometers quickly evolved, there
arose a need for a more powerful and user-friendly analysis and display program.
The development of FlowJo’s graphical user interface made practical the analysis of the extremely voluminous cytometric data.
FlowJo became a commercial product in 1996. In 2002, Tree
Star released a Windows version. More information about the use and function of FlowJo is available at its website. | FlowJo
FlowJo is the name of a piece of software for analyzing flow cytometry data. Files produced by modern flow cytometers are written in a standard format called .fcs. Hence FlowJo will import and analyze cytometry data regardless of which FACS (Fluorescence Activated Cell Sorting) machine is
used to collect the samples. In FlowJo samples are organized in a "Workspace" window, which presents a hierarchical view of all the samples and their analyses (gates and statistics). Viewing an entire experiment in a Workspace enables you to organize and manage complex cytometry experiments while making detailed graphical reports.
Within a workspace, samples can be grouped or sorted by various attributes
such as the panel of antibodies with which they are stained, tissue type, or
patient from whom they came. When one performs an operation on a group, FlowJo performs the same
operation on every sample belonging to that group. Thus, you can apply a
gate to a sample, copy it to a group, and that gate will be automatically placed on all samples in the group.
FlowJo's ability to automate repetitive operations
facilitates the production of statistics tables and graphical
reports when the experiment involves many samples, parameters and/or operations.
FlowJo provides tools for the creation of:
Histogram and other plot overlays
Cell cycle analysis
Calcium flux analysis
Proliferation analysis
Quantitation
Cluster identification
and backgating display.
Tree Star, Inc. began as a software company in 1989. At that time, the authors' work at Stanford University’s Information Technology department
brought them into contact with the Herzenberg Laboratory where modern
flow cytometry originated. As the utility and power of cytometers quickly evolved, there
arose a need for a more powerful and user-friendly analysis and display program.
The development of FlowJo’s graphical user interface made practical the analysis of the extremely voluminous cytometric data.
FlowJo became a commercial product in 1996. In 2002, Tree
Star released a Windows version. More information about the use and function of FlowJo is available at its website.
Template:WH
Template:WikiDoc Sources | https://www.wikidoc.org/index.php/FlowJo | |
ade8bfd985f2ac8af44e2e7ad8319d3b0b08b99b | wikidoc | Fomite | Fomite
A fomite is any inanimate object or substance capable of carrying infectious organisms (such as germs or parasites) and hence transferring them from one individual to another. A fomite can be anything such as a cloth or mop heads so when cleaning this is important to remember that this could aid when spreading pathogenic organisms.
There are many examples of fomites with respect to medicine. Contaminated shoes may spread hoof and mouth disease. Other examples include tools such as laryngoscopes that are not properly disinfected between uses, dirty towels, eating utensils, and surfaces such as floors, walls, and tables may all serve to spread disease.
Researchers discovered that smooth (non-porous) surfaces transmit bacteria and viruses better than porous materials; so one is more likely to pick-up a disease from a door knob than from paper money. The reasoning is that porous, especially fibrous, materials absorb and trap the contagion, making it harder to contract through simply touching.
# Etymology
The word fomite is a back-formation from the plural fomites, which was originally the Latin plural of the singular, fomes (rhymes with "homies"), literally meaning touchwood or tinder. As a Latin plural, fomites was originally pronounced like the English word concatenation "foam" + "it" + "ease"; but "foe" + "mites" has now become a common pronunciation, and "fomite" (also pronounced with a long 'i') is now an accepted synonym for fomes.
Note: The original Latin pronunciation would have been "foam" + "it" + "ace"; in other words, "fomites" pronounced as a Spanish or Italian speaker would pronounce it. | Fomite
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
A fomite is any inanimate object or substance capable of carrying infectious organisms (such as germs or parasites) and hence transferring them from one individual to another. A fomite can be anything such as a cloth or mop heads so when cleaning this is important to remember that this could aid when spreading pathogenic organisms.
There are many examples of fomites with respect to medicine. Contaminated shoes may spread hoof and mouth disease. Other examples include tools such as laryngoscopes that are not properly disinfected between uses, dirty towels, eating utensils, and surfaces such as floors, walls, and tables may all serve to spread disease.
Researchers discovered that smooth (non-porous) surfaces transmit bacteria and viruses better than porous materials; so one is more likely to pick-up a disease from a door knob than from paper money. The reasoning is that porous, especially fibrous, materials absorb and trap the contagion, making it harder to contract through simply touching.
# Etymology
The word fomite is a back-formation from the plural fomites, which was originally the Latin plural of the singular, fomes (rhymes with "homies"), literally meaning touchwood or tinder. As a Latin plural, fomites was originally pronounced like the English word concatenation "foam" + "it" + "ease"; but "foe" + "mites" has now become a common pronunciation, and "fomite" (also pronounced with a long 'i') is now an accepted synonym for fomes.
Note: The original Latin pronunciation would have been "foam" + "it" + "ace"; in other words, "fomites" pronounced as a Spanish or Italian speaker would pronounce it.
Template:WH
Template:WS | https://www.wikidoc.org/index.php/Fomite | |
93ae8c75602336aeabd28814b95f206895782c36 | wikidoc | Fossil | Fossil
Fossils (from Latin fossus, literally "having been dug up") are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record. The study of fossils across geological time, how they were formed, and the evolutionary relationships between taxa (phylogeny) are some of the most important functions of the science of paleontology.
The relative geological time scale was developed during the 1800s based largely on the fossil content of the rock strata. The development of radiometric dating techniques in the early 1900s allowed geologists to determined the absolute age of the various strata and the included fossils. Fossils range in age from the relatively recent Holocene Epoch several thousands of years in age to those of the Archaean Era several billions of years old.
Fossils vary in size from microscopic, such as single cells, to gigantic, such as dinosaurs. A fossil normally preserves only a portion of the deceased organism, usually that portion that was partially mineralized during life, such as the bones and teeth of vertebrates, or the chitinous exoskeletons of invertebrates. But preservation of soft tissues is exquisitely rare in the fossil record. Fossils may also consist of the marks left behind by the organism while it was alive, such as the footprint or faeces (feces) (Coprolites) of a reptile. These types of fossil are called trace fossils (or ichnofossils), as opposed to body fossils. Finally, past life leaves some markers that cannot be seen but can be detected in the form of biochemical signals; these are known as chemofossils or biomarkers.
# Places of exceptional fossilization
Fossil sites with exceptional preservation -- sometimes including preserved soft tissues -- are known as Lagerstätten. These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus delaying decomposition. Lagerstätten span geological time from the Cambrian period to the present. Worldwide, some of the best examples of near-perfect fossilization are the Cambrian Maotianshan shales and Burgess Shale, the Devonian Hunsrück Slates, the Jurassic Solnhofen limestone, and the Carboniferous Mazon Creek localities.
# Earliest fossiliferous sites
Earth’s oldest fossils are the stromatolites consisting of rock built from layer upon layer of sediment and precipitants. Based on studies of now-rare (but living) stromatolites (specifically, certain blue-green bacteria), the growth of fossil stromatolitic structures was biogenetically mediated by mats of microorganisms through their entrapment of sediments. However, abiotic mechanisms for stromatolitic growth are also known, leading to a decades-long and sometimes-contentious scientific debate regarding biogenesis of certain formations, especially those from the lower to middle Archaean eon.
It is more widely accepted that stromatolites from the late Archaean and through the middle Proterozoic eon were mostly formed by massive colonies of cyanobacteria (formerly known as blue-green "algae"), and that the oxygen byproduct of their photosynthetic metabolism first resulted in earth’s massive banded iron formations and subsequently oxygenated earth’s atmosphere.
Though rare, microstructures resembling cells are sometimes found within stromatolites; but these are also the source of scientific contention. The Gunflint Chert contains abundant microfossils widely accepted as a diverse consortium of 2.0 bya microbes.
In contrast, putative fossil cyanobacteria cells from the 3.4 bya Warrawoona Group in Western Australia are in dispute since abiotic processes cannot be ruled out. Confirmation of the Warrawoona microstructures as cyanobacteria would profoundly impact our understanding of when and how early life diversified, pushing important evolutionary milestones further back in time (reference). The continued study of these oldest fossils is paramount to calibrate complementary molecular phylogenetics models.
# Developments in interpretation of the fossil record
Ever since recorded history began, and probably before, people have found fossils, pieces of rock and minerals which have replaced the remains of biologic organisms or preserved their external form. These fossils, and the totality of their occurrence within the sequence of Earth's rock strata is referred to as the fossil record.
The fossil record was one of the early sources of data relevant to the study of evolution and continues to be relevant to the history of life on Earth. Paleontologists examine the fossil record in order to understand the process of evolution and the way particular species have evolved.
Various explanations have been put forth throughout history to explain what fossils are and how they came to be where they were found. Many of these explanations relied on folktales or mythologies. In China the fossil bones of ancient mammals including Homo erectus were often mistaken for “dragon bones” and used as medicine and aphrodisiacs. In the West the presence of fossilized sea creatures high up on mountainsides was seen as proof of the biblical deluge. More scientific views of fossils began to emerge during the Renaissance. For example, Leonardo Da Vinci noticed discrepancies with the use of the biblical flood narrative as an explanation for fossil origins:
William Smith (1769-1839), an English canal engineer, observed that rocks of different ages (based on the law of superposition) preserved different assemblages of fossils, and that these assemblages succeeded one another in a regular and determinable order. He observed that rocks from distant locations could be correlated based on the fossils they contained. He termed this the principle of faunal succession.
Smith, who preceded Charles Darwin, was unaware of biological evolution and did not know why faunal succession occurred. Biological evolution explains why faunal succession exists: as different organisms evolve, change and go extinct, they leave behind fossils. Faunal succession was one of the chief pieces of evidence cited by Darwin that biological evolution had occurred.
Early naturalists well understood the similarities and differences of living species leading Linnaeus to develop a hierarchical classification system still in use today. It was Darwin and his contemporaries who first linked the hierarchical structure of the great tree of life in living organisms with the then very sparse fossil record. Darwin eloquently described a process of descent with modification, or evolution, whereby organisms either adapt to natural and changing environmental pressures, or they perish.
When Charles Darwin wrote On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, the oldest animal fossils were those from the Cambrian Period, now known to be about 540 million years old. The absence of older fossils worried Darwin about the implications for the validity of his theories, but he expressed hope that such fossils would be found, noting that: "only a small portion of the world is known with accuracy." Darwin also pondered the sudden appearance of many groups (i.e. phyla) in the oldest known Cambrian fossiliferous strata.
Since Darwin's time, the fossil record has been pushed back to 3.5 billion years before the present. Most of these Precambrian fossils are microscopic bacteria or microfossils. However, macroscopic fossils are now known from the late Proterozoic. The Ediacaran biota (also called Vendian biota) dating from 575 million years ago collectively constitutes a richly diverse assembly of early multicellular eukaryotes.
The fossil record and faunal succession form the basis of the science of biostratigraphy or determining the age of rocks based on the fossils they contain. For the first 150 years of geology, biostratigraphy and superposition were the only means for determining the relative age of rocks. The geologic time scale was developed based on the relative ages of rock strata as determined by the early paleontologists and stratigraphers.
Since the early years of the twentieth century, absolute dating methods, such as radiometric dating (including potassium/argon, argon/argon, uranium series, and carbon-14 dating) have been used to verify the relative ages obtained by fossils and to provide absolute ages for many fossils. Radiometric dating has shown that the earliest known fossils are over 3.5 billion years old. Various dating methods have been used and are used today depending on local geology and context, and while there is some variance in the results from these dating methods, nearly all of them provide evidence for a very old Earth, approximately 4.6 billion years.
“The fossil record is life’s evolutionary epic that unfolded over four billion years as environmental conditions and genetic potential interacted in accordance with natural selection.” The earth’s climate, tectonics, atmosphere, oceans, and periodic disasters invoked the primary selective pressures on all organisms, which they either adapted to, or they perished with or without leaving descendants. Modern paleontology has joined with evolutionary biology to share the interdisciplinary task of unfolding the tree of life, which inevitably leads backwards in time to the microscopic life of the Precambrian when cell structure and functions evolved. Earth’s deep time in the Proterozoic and deeper still in the Archaean is only “recounted by microscopic fossils and subtle chemical signals”. Molecular biologists, using phylogenetics, can compare protein amino acid or nucleotide sequence homology (i.e., similarity) to infer taxonomy and evolutionary distances among organisms, but with limited statistical confidence. The study of fossils, on the other hand, can more specifically pin point when and in what organism branching occurred in the tree of life. Modern phylogenetics and paleontology work together in the clarification of science’s still dim view of the appearance life and its evolution during deep time on earth.
Niles Eldredge’s study of the Phacops trilobite genus supported the hypothesis that modifications to the arrangement of the trilobite’s eye lenses proceeded by fits and starts over millions of years during the Devonian. Eldredge's interpretation of the Phacops fossil record was that the aftermaths of the lens changes, but not the rapidly occurring evolutionary process, were fossilised. This and other data led Stephen Jay Gould and Niles Eldredge to publish the seminal paper on punctuated equilibrium in 1971.
An example of modern paleontological progress is the application of synchrotron X-ray tomographic techniques to early Cambrian bilaterian embryonic microfossils that has recently yielded new insights of metazoan evolution at its earliest stages. The tomography technique provides previously unattainable three-dimensional resolution at the limits of fossilization. Fossils of two enigmatic bilaterians, the worm-like Markuelia and a putative, primitive protostome, Pseudooides, provide a peek at germ layer embryonic development. These 543 Ma old embryos support the emergence of some aspects of arthropod development earlier than previously thought in the late Proterozoic. The preserved embryos from China and Siberia underwent rapid diagenetic phosphatization resulting in exquisite preservation, including cell structures. This research is a notable example of how knowledge encoded by the fossil record continues to contribute otherwise unattainable information on the emergence and development of life on Earth. For example, the research suggests Markuelia has closest affinity to priapulid worms, and is adjacent to the evolutionary branching of Priapulida, Nematoda and Arthropoda.
Even with the wealth of information now known about fossils, some groups maintain non-scientific beliefs based on the earlier views of the fossil record.
# Rarity of fossils
Fossilization is an exceptionally rare occurrence, because most components of formerly-living things tend to decompose relatively quickly following death. In order for an organism to be fossilized, the remains normally need to be covered by sediment as soon as possible. However there are exceptions to this, such as if an organism becomes frozen, desiccated, or comes to rest in an anoxic (oxygen-free) environment. There are several different types of fossils and fossilization processes.
Due to the combined effect of taphonomic processes and simple mathematical chance, fossilization tends to favor organisms with hard body parts, those that were widespread, and those that lived for a long time. On the other hand, it is very unusual to find fossils of small, soft bodied, geographically restricted and geologically ephemeral organisms, because of their relative rarity and low likelihood of preservation.
Larger specimens (macrofossils) are more often observed, dug up and displayed, although microscopic remains (microfossils) are actually far more common in the fossil record.
Some casual observers have been perplexed by the rarity of transitional species within the fossil record. The conventional explanation for this rarity was given by Darwin, who stated that "the extreme imperfection of the geological record," combined with the short duration and narrow geographical range of transitional species, made it unlikely that many such fossils would be found. Simply put, the conditions under which fossilization takes place are quite rare; and it is highly unlikely that any given organism will leave behind a fossil. Eldredge and Gould developed their theory of punctuated equilibrium in part to explain the pattern of stasis and sudden appearance in the fossil record.
# Permineralization
Permineralization occurs after burial, as the empty spaces within an organism (spaces filled with liquid or gas during life) become filled with mineral-rich groundwater and the minerals precipitate from the groundwater, thus occupying the empty spaces. This process can occur in very small spaces, such as within the cell wall of a plant cell. Small scale permineralization can produce very detailed fossils. For permineralization to occur, the organism must become covered by sediment soon after death or soon after the initial decaying process. The degree to which the remains are decayed when covered determines the later details of the fossil. Some fossils consist only of skeletal remains or teeth; other fossils contain traces of skin, feathers or even soft tissues. This is a form of diagenesis.
# Replacement and compression fossils
In some cases the original remains of the organism have been completely dissolved or otherwise destroyed. When all that is left is an organism-shaped hole in the rock, it is called a mould fossil or typolite. If this hole is later filled with other minerals, it is called a cast fossil and is considered a replacement fossil since the original materials have been completely replaced by new, unrelated ones. In some cases replacement occurs so gradually and at such fine scales that no "hole" in the rock can ever be discerned and microstructural features are preserved despite the total loss of original material.
Compression fossils such as those of fossil ferns are the result of chemical reduction of the complex organic molecules composing the organism's tissues. In this case the fossil consists of original material, albeit in a geochemically altered state. This chemical change is an expression of diagenesis.
To sum up, fossilization processes proceed differently for different kinds of tissues and under different kinds of conditions.
# Trace fossils
Trace fossils are the remains of trackways, burrows, bioerosion, eggs and eggshells, nests, droppings and other types of impressions. Fossilized droppings, called coprolites, can give insight into the feeding behaviour of animals and can therefore be of great importance.
# Microfossils
'Microfossil' is a descriptive term applied to fossilized plants and animals whose size is just at or below the level at which the fossil can be analyzed by the naked eye. A commonly applied cut-off point between "micro" and "macro" fossils is 1 mm, although this is only an approximate guide. Microfossils may either be complete (or near-complete) organisms in themselves (such as the marine plankters foraminifera and coccolithophores) or component parts (such as small teeth or spores) of larger animals or plants. Microfossils are of critical importance as a reservoir of paleoclimate information, and are also commonly used by biostratigraphers to assist in the correlation of rock units.
# Resin fossils
Fossil resin (colloquially called amber) is a natural polymer found in many types of strata throughout the world, even the Arctic. The oldest fossil resin dates to the Triassic, though most dates to the Tertiary. The excretion of the resin by certain plants is thought to be an evolutionary adaptation for protection from insects and to seal wounds caused by damage elements. Fossil resin often contains other fossils called inclusions that were captured by the sticky resin. These include bacteria, fungi, other plants, and animals. Animal inclusions are usually small invertebrates, predominantly arthropods such as insects and spiders, and only extremely rarely a vertebrate such as a small lizard. Preservation of inclusions can be exquisite, including small fragments of DNA.
# Pseudofossils
Pseudofossils are visual patterns in rocks that are produced by naturally occurring geologic processes rather than biologic processes. They can easily be mistaken for real fossils. Some pseudofossils, such as dendrites, are formed by naturally occurring fissures in the rock that get filled up by percolating minerals. Other types of pseudofossils are kidney ore (round shapes in iron ore) and moss agates, which look like moss or plant leaves. Concretions, spherical or ovoid-shaped nodules found in some sedimentary strata, were once thought to be dinosaur eggs, and are often mistaken for fossils as well.
# Living fossils
Living fossil is an informal term used for any living species which closely resembles a species known from fossils -- that is, it is as if the ancient fossil had "come to life."
This can be (a) a species or taxon known only from fossils until living representatives were discovered, such as the lobed-finned coelacanth, primitive monoplacophoran mollusk, and the Chinese maidenhair tree, or (b) a single living species with no close relatives, such as the New Caledonian Kagu, or the Sunbittern, or (c) a small group of closely-related species with no other close relatives, such as the oxygen-producing, primoidial stromatolite, inarticulate lampshell Lingula, many-chambered pearly Nautilus, rootless whisk fern, armored horseshoe crab, and dinosaur-like tuatara that are the sole survivors of a once large and widespread group in the fossil record. | Fossil
Fossils (from Latin fossus, literally "having been dug up") are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record. The study of fossils across geological time, how they were formed, and the evolutionary relationships between taxa (phylogeny) are some of the most important functions of the science of paleontology.
The relative geological time scale was developed during the 1800s based largely on the fossil content of the rock strata. The development of radiometric dating techniques in the early 1900s allowed geologists to determined the absolute age of the various strata and the included fossils. Fossils range in age from the relatively recent Holocene Epoch several thousands of years in age to those of the Archaean Era several billions of years old.
Fossils vary in size from microscopic, such as single cells, to gigantic, such as dinosaurs. A fossil normally preserves only a portion of the deceased organism, usually that portion that was partially mineralized during life, such as the bones and teeth of vertebrates, or the chitinous exoskeletons of invertebrates. But preservation of soft tissues is exquisitely rare in the fossil record. Fossils may also consist of the marks left behind by the organism while it was alive, such as the footprint or faeces (feces) (Coprolites) of a reptile. These types of fossil are called trace fossils (or ichnofossils), as opposed to body fossils. Finally, past life leaves some markers that cannot be seen but can be detected in the form of biochemical signals; these are known as chemofossils or biomarkers.
# Places of exceptional fossilization
Fossil sites with exceptional preservation -- sometimes including preserved soft tissues -- are known as Lagerstätten. These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus delaying decomposition. Lagerstätten span geological time from the Cambrian period to the present. Worldwide, some of the best examples of near-perfect fossilization are the Cambrian Maotianshan shales and Burgess Shale, the Devonian Hunsrück Slates, the Jurassic Solnhofen limestone, and the Carboniferous Mazon Creek localities.
# Earliest fossiliferous sites
Earth’s oldest fossils are the stromatolites consisting of rock built from layer upon layer of sediment and precipitants.[1] Based on studies of now-rare (but living) stromatolites (specifically, certain blue-green bacteria), the growth of fossil stromatolitic structures was biogenetically mediated by mats of microorganisms through their entrapment of sediments. However, abiotic mechanisms for stromatolitic growth are also known, leading to a decades-long and sometimes-contentious scientific debate regarding biogenesis of certain formations, especially those from the lower to middle Archaean eon.
It is more widely accepted that stromatolites from the late Archaean and through the middle Proterozoic eon were mostly formed by massive colonies of cyanobacteria (formerly known as blue-green "algae"), and that the oxygen byproduct of their photosynthetic metabolism first resulted in earth’s massive banded iron formations and subsequently oxygenated earth’s atmosphere.
Though rare, microstructures resembling cells are sometimes found within stromatolites; but these are also the source of scientific contention. The Gunflint Chert contains abundant microfossils widely accepted as a diverse consortium of 2.0 bya microbes.[2]
In contrast, putative fossil cyanobacteria cells from the 3.4 bya Warrawoona Group in Western Australia are in dispute since abiotic processes cannot be ruled out.[3] Confirmation of the Warrawoona microstructures as cyanobacteria would profoundly impact our understanding of when and how early life diversified, pushing important evolutionary milestones further back in time (reference). The continued study of these oldest fossils is paramount to calibrate complementary molecular phylogenetics models.
# Developments in interpretation of the fossil record
Template:Seealso
Ever since recorded history began, and probably before, people have found fossils, pieces of rock and minerals which have replaced the remains of biologic organisms or preserved their external form. These fossils, and the totality of their occurrence within the sequence of Earth's rock strata is referred to as the fossil record.
The fossil record was one of the early sources of data relevant to the study of evolution and continues to be relevant to the history of life on Earth. Paleontologists examine the fossil record in order to understand the process of evolution and the way particular species have evolved.
Various explanations have been put forth throughout history to explain what fossils are and how they came to be where they were found. Many of these explanations relied on folktales or mythologies. In China the fossil bones of ancient mammals including Homo erectus were often mistaken for “dragon bones” and used as medicine and aphrodisiacs. In the West the presence of fossilized sea creatures high up on mountainsides was seen as proof of the biblical deluge. More scientific views of fossils began to emerge during the Renaissance. For example, Leonardo Da Vinci noticed discrepancies with the use of the biblical flood narrative as an explanation for fossil origins:
William Smith (1769-1839), an English canal engineer, observed that rocks of different ages (based on the law of superposition) preserved different assemblages of fossils, and that these assemblages succeeded one another in a regular and determinable order. He observed that rocks from distant locations could be correlated based on the fossils they contained. He termed this the principle of faunal succession.
Smith, who preceded Charles Darwin, was unaware of biological evolution and did not know why faunal succession occurred. Biological evolution explains why faunal succession exists: as different organisms evolve, change and go extinct, they leave behind fossils. Faunal succession was one of the chief pieces of evidence cited by Darwin that biological evolution had occurred.
Early naturalists well understood the similarities and differences of living species leading Linnaeus to develop a hierarchical classification system still in use today. It was Darwin and his contemporaries who first linked the hierarchical structure of the great tree of life in living organisms with the then very sparse fossil record. Darwin eloquently described a process of descent with modification, or evolution, whereby organisms either adapt to natural and changing environmental pressures, or they perish.
When Charles Darwin wrote On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, the oldest animal fossils were those from the Cambrian Period, now known to be about 540 million years old. The absence of older fossils worried Darwin about the implications for the validity of his theories, but he expressed hope that such fossils would be found, noting that: "only a small portion of the world is known with accuracy." Darwin also pondered the sudden appearance of many groups (i.e. phyla) in the oldest known Cambrian fossiliferous strata[4].
Since Darwin's time, the fossil record has been pushed back to 3.5 billion years before the present[5]. Most of these Precambrian fossils are microscopic bacteria or microfossils. However, macroscopic fossils are now known from the late Proterozoic. The Ediacaran biota (also called Vendian biota) dating from 575 million years ago collectively constitutes a richly diverse assembly of early multicellular eukaryotes.
The fossil record and faunal succession form the basis of the science of biostratigraphy or determining the age of rocks based on the fossils they contain. For the first 150 years of geology, biostratigraphy and superposition were the only means for determining the relative age of rocks. The geologic time scale was developed based on the relative ages of rock strata as determined by the early paleontologists and stratigraphers.
Since the early years of the twentieth century, absolute dating methods, such as radiometric dating (including potassium/argon, argon/argon, uranium series, and carbon-14 dating) have been used to verify the relative ages obtained by fossils and to provide absolute ages for many fossils. Radiometric dating has shown that the earliest known fossils are over 3.5 billion years old. Various dating methods have been used and are used today depending on local geology and context, and while there is some variance in the results from these dating methods, nearly all of them provide evidence for a very old Earth, approximately 4.6 billion years.
“The fossil record is life’s evolutionary epic that unfolded over four billion years as environmental conditions and genetic potential interacted in accordance with natural selection.”[6] The earth’s climate, tectonics, atmosphere, oceans, and periodic disasters invoked the primary selective pressures on all organisms, which they either adapted to, or they perished with or without leaving descendants. Modern paleontology has joined with evolutionary biology to share the interdisciplinary task of unfolding the tree of life, which inevitably leads backwards in time to the microscopic life of the Precambrian when cell structure and functions evolved. Earth’s deep time in the Proterozoic and deeper still in the Archaean is only “recounted by microscopic fossils and subtle chemical signals”[7]. Molecular biologists, using phylogenetics, can compare protein amino acid or nucleotide sequence homology (i.e., similarity) to infer taxonomy and evolutionary distances among organisms, but with limited statistical confidence. The study of fossils, on the other hand, can more specifically pin point when and in what organism branching occurred in the tree of life. Modern phylogenetics and paleontology work together in the clarification of science’s still dim view of the appearance life and its evolution during deep time on earth[8].
Niles Eldredge’s study of the Phacops trilobite genus supported the hypothesis that modifications to the arrangement of the trilobite’s eye lenses proceeded by fits and starts over millions of years during the Devonian[9]. Eldredge's interpretation of the Phacops fossil record was that the aftermaths of the lens changes, but not the rapidly occurring evolutionary process, were fossilised. This and other data led Stephen Jay Gould and Niles Eldredge to publish the seminal paper on punctuated equilibrium in 1971.
An example of modern paleontological progress is the application of synchrotron X-ray tomographic techniques to early Cambrian bilaterian embryonic microfossils that has recently yielded new insights of metazoan evolution at its earliest stages. The tomography technique provides previously unattainable three-dimensional resolution at the limits of fossilization. Fossils of two enigmatic bilaterians, the worm-like Markuelia and a putative, primitive protostome, Pseudooides, provide a peek at germ layer embryonic development. These 543 Ma old embryos support the emergence of some aspects of arthropod development earlier than previously thought in the late Proterozoic. The preserved embryos from China and Siberia underwent rapid diagenetic phosphatization resulting in exquisite preservation, including cell structures. This research is a notable example of how knowledge encoded by the fossil record continues to contribute otherwise unattainable information on the emergence and development of life on Earth. For example, the research suggests Markuelia has closest affinity to priapulid worms, and is adjacent to the evolutionary branching of Priapulida, Nematoda and Arthropoda[10].
Even with the wealth of information now known about fossils, some groups maintain non-scientific beliefs based on the earlier views of the fossil record.
# Rarity of fossils
Fossilization is an exceptionally rare occurrence, because most components of formerly-living things tend to decompose relatively quickly following death. In order for an organism to be fossilized, the remains normally need to be covered by sediment as soon as possible. However there are exceptions to this, such as if an organism becomes frozen, desiccated, or comes to rest in an anoxic (oxygen-free) environment. There are several different types of fossils and fossilization processes.
Due to the combined effect of taphonomic processes and simple mathematical chance, fossilization tends to favor organisms with hard body parts, those that were widespread, and those that lived for a long time. On the other hand, it is very unusual to find fossils of small, soft bodied, geographically restricted and geologically ephemeral organisms, because of their relative rarity and low likelihood of preservation.
Larger specimens (macrofossils) are more often observed, dug up and displayed, although microscopic remains (microfossils) are actually far more common in the fossil record.
Some casual observers have been perplexed by the rarity of transitional species within the fossil record. The conventional explanation for this rarity was given by Darwin, who stated that "the extreme imperfection of the geological record," combined with the short duration and narrow geographical range of transitional species, made it unlikely that many such fossils would be found. Simply put, the conditions under which fossilization takes place are quite rare; and it is highly unlikely that any given organism will leave behind a fossil. Eldredge and Gould developed their theory of punctuated equilibrium in part to explain the pattern of stasis and sudden appearance in the fossil record.
# Permineralization
Permineralization occurs after burial, as the empty spaces within an organism (spaces filled with liquid or gas during life) become filled with mineral-rich groundwater and the minerals precipitate from the groundwater, thus occupying the empty spaces. This process can occur in very small spaces, such as within the cell wall of a plant cell. Small scale permineralization can produce very detailed fossils. For permineralization to occur, the organism must become covered by sediment soon after death or soon after the initial decaying process. The degree to which the remains are decayed when covered determines the later details of the fossil. Some fossils consist only of skeletal remains or teeth; other fossils contain traces of skin, feathers or even soft tissues. This is a form of diagenesis.
# Replacement and compression fossils
In some cases the original remains of the organism have been completely dissolved or otherwise destroyed. When all that is left is an organism-shaped hole in the rock, it is called a mould fossil or typolite. If this hole is later filled with other minerals, it is called a cast fossil and is considered a replacement fossil since the original materials have been completely replaced by new, unrelated ones. In some cases replacement occurs so gradually and at such fine scales that no "hole" in the rock can ever be discerned and microstructural features are preserved despite the total loss of original material.
Compression fossils such as those of fossil ferns are the result of chemical reduction of the complex organic molecules composing the organism's tissues. In this case the fossil consists of original material, albeit in a geochemically altered state. This chemical change is an expression of diagenesis.
To sum up, fossilization processes proceed differently for different kinds of tissues and under different kinds of conditions.
# Trace fossils
Trace fossils are the remains of trackways, burrows, bioerosion, eggs and eggshells, nests, droppings and other types of impressions. Fossilized droppings, called coprolites, can give insight into the feeding behaviour of animals and can therefore be of great importance.
# Microfossils
'Microfossil' is a descriptive term applied to fossilized plants and animals whose size is just at or below the level at which the fossil can be analyzed by the naked eye. A commonly applied cut-off point between "micro" and "macro" fossils is 1 mm, although this is only an approximate guide. Microfossils may either be complete (or near-complete) organisms in themselves (such as the marine plankters foraminifera and coccolithophores) or component parts (such as small teeth or spores) of larger animals or plants. Microfossils are of critical importance as a reservoir of paleoclimate information, and are also commonly used by biostratigraphers to assist in the correlation of rock units.
# Resin fossils
Fossil resin (colloquially called amber) is a natural polymer found in many types of strata throughout the world, even the Arctic. The oldest fossil resin dates to the Triassic, though most dates to the Tertiary. The excretion of the resin by certain plants is thought to be an evolutionary adaptation for protection from insects and to seal wounds caused by damage elements. Fossil resin often contains other fossils called inclusions that were captured by the sticky resin. These include bacteria, fungi, other plants, and animals. Animal inclusions are usually small invertebrates, predominantly arthropods such as insects and spiders, and only extremely rarely a vertebrate such as a small lizard. Preservation of inclusions can be exquisite, including small fragments of DNA.
# Pseudofossils
Pseudofossils are visual patterns in rocks that are produced by naturally occurring geologic processes rather than biologic processes. They can easily be mistaken for real fossils. Some pseudofossils, such as dendrites, are formed by naturally occurring fissures in the rock that get filled up by percolating minerals. Other types of pseudofossils are kidney ore (round shapes in iron ore) and moss agates, which look like moss or plant leaves. Concretions, spherical or ovoid-shaped nodules found in some sedimentary strata, were once thought to be dinosaur eggs, and are often mistaken for fossils as well.
# Living fossils
Living fossil is an informal term used for any living species which closely resembles a species known from fossils -- that is, it is as if the ancient fossil had "come to life."
This can be (a) a species or taxon known only from fossils until living representatives were discovered, such as the lobed-finned coelacanth, primitive monoplacophoran mollusk, and the Chinese maidenhair tree, or (b) a single living species with no close relatives, such as the New Caledonian Kagu, or the Sunbittern, or (c) a small group of closely-related species with no other close relatives, such as the oxygen-producing, primoidial stromatolite, inarticulate lampshell Lingula, many-chambered pearly Nautilus, rootless whisk fern, armored horseshoe crab, and dinosaur-like tuatara that are the sole survivors of a once large and widespread group in the fossil record. | https://www.wikidoc.org/index.php/Fossil | |
6065ddc229785360084a018397ad291177ba9438 | wikidoc | Fungus | Fungus
A fungus (Template:PronEng) is a eukaryotic organism that is a member of the kingdom Fungi (Template:PronEng). The fungi are heterotrophic organisms possessing a chitinous cell wall. The majority of species grow as multicellular filaments called hyphae forming a mycelium; some fungal species also grow as single cells. Sexual and asexual reproduction of the fungi is commonly via spores, often produced on specialized structures or in fruiting bodies. Some species have lost the ability to form specialized reproductive structures, and propagate solely by vegetative growth. Yeasts, molds, and mushrooms are examples of fungi. The fungi are a monophyletic group that is phylogenetically clearly distinct from the morphologically similar slime molds (myxomycetes) and water molds (oomycetes). The fungi are more closely related to animals than plants, yet the discipline of biology devoted to the study of fungi, known as mycology, often falls under a branch of botany.
Occurring worldwide, most fungi are largely invisible to the naked eye, living for the most part in soil, dead matter, and as symbionts of plants, animals, or other fungi. They perform an essential role in all ecosystems in decomposing organic matter and are indispensable in nutrient cycling and exchange. Some fungi become noticeable when fruiting, either as mushrooms or molds. Many fungal species have long been used as a direct source of food, such as mushrooms and truffles and in fermentation of various food products, such as wine, beer, and soy sauce. More recently, fungi are being used as sources for antibiotics used in medicine and various enzymes, such as cellulases, pectinases, and proteases, important for industrial use or as active ingredients of detergents. Many fungi produce bioactive compounds called mycotoxins, such as alkaloids and polyketides that are toxic to animals including humans. Some fungi are used recreationally or in traditional ceremonies as a source of psychotropic compounds. Several species of the fungi are significant pathogens of humans and other animals, and losses due to diseases of crops (e.g., rice blast disease) or food spoilage caused by fungi can have a large impact on human food supply and local economies.
# Etymology and definition
The English word fungus is directly adopted from the Latin fungus, meaning "mushroom", used in Horace and Pliny. This in turn is derived from the Greek word sphongos/σφογγος ("sponge"), referring to the macroscopic structures and morphology of some mushrooms and molds and also used in other languages (e.g., the German Schwamm ("sponge") or Schwammerl for some types of mushroom).
# Diversity
Fungi have a worldwide distribution, and grow in a wide range of habitats, including deserts. Most fungi grow in terrestrial environments, but several species occur only in aquatic habitats. Fungi along with bacteria are the primary decomposers of organic matter in most if not all terrestrial ecosystems worldwide. Based on observations of the ratio of the number of fungal species to the number of plant species in some environments, the fungal kingdom has been estimated to contain about 1.5 million species. Around 70,000 fungal species have been formally described by taxonomists, but the true dimension of fungal diversity is still unknown. Most fungi grow as thread-like filaments called hyphae, which form a mycelium, while others grow as single cells. Until recently many fungal species were described based mainly on morphological characteristics, such as the size and shape of spores or fruiting structures, and biological species concepts; the application of molecular tools, such as DNA sequencing, to study fungal diversity has greatly enhanced the resolution and added robustness to estimates of diversity within various taxonomic groups.
# Importance for human use
Human use of fungi for food preparation or preservation and other purposes is extensive and has a long history: yeasts are required for fermentation of beer, wine and bread, some other fungal species are used in the production of soy sauce and tempeh. Mushroom farming and mushroom gathering are large industries in many countries. Many fungi are producers of antibiotics, including β-lactam antibiotics such as penicillin and cephalosporin. Widespread use of these antibiotics for the treatment of bacterial diseases, such as tuberculosis, syphilis, leprosy, and many others began in the early 20th century and continues to play a major part in anti-bacterial chemotherapy. The study of the historical uses and sociological impact of fungi is known as ethnomycology.
### Cultured foods
Baker's yeast or Saccharomyces cerevisiae, a single-cell fungus, is used in the baking of bread and other wheat-based products, such as pizza and dumplings. Several yeast species of the genus Saccharomyces are also used in the production of alcoholic beverages through fermentation. Mycelial fungi, such as the shoyu koji mold (Aspergillus oryzae), are used in the brewing of Shoyu (soy sauce) and preparation of tempeh. Quorn is a high-protein product made from the mold, Fusarium venenatum, and is used in vegetarian cooking.
### Other human uses
Fungi are also used extensively to produce industrial chemicals like lactic acid, antibiotics and even to make stonewashed jeans. Several fungal species are ingested for their psychedelic properties, both recreationally and religiously (see main article, Psilocybin mushrooms).
### Mycotoxins
Many fungi produce compounds with biological activity. Several of these compounds are toxic and are therefore called mycotoxins, referring to their fungal origin and toxic activity. Of particular relevance to humans are those mycotoxins that are produced by moulds causing food spoilage and poisonous mushrooms (see below). Particularly infamous are the aflatoxins, which are insidious liver toxins and highly carcinogenic metabolites produced by Aspergillus species often growing in or on grains and nuts consumed by humans, and the lethal amatoxins produced by mushrooms of the genus Amanita. Other notable mycotoxins include ochratoxins, patulin, ergot alkaloids, and trichothecenes and fumonisins, all of which have significant impact on human food supplies or animal livestock.
Mycotoxins belong to the group of secondary metabolites (or natural products). Originally, this group of compounds had been thought to be mere byproducts of primary metabolism, hence the name "secondary" metabolites. However, recent research has shown the existence of biochemical pathways solely for the purpose of producing mycotoxins and other natural products in fungi. Mycotoxins provide a number of fitness benefits to the fungi that produce them in terms of physiological adaptation, competition with other microbes and fungi, and protection from fungivory. These fitness benefits and the existence of dedicated biosynthetic pathways for mycotoxin production suggest that the mycotoxins are important for fungal persistence and survival.
### Edible and poisonous fungi
Some of the best known types of fungi are the edible and the poisonous mushrooms. Many species are commercially raised, but others must be harvested from the wild. Agaricus bisporus, sold as button mushrooms when small or Portobello mushrooms when larger, are the most commonly eaten species, used in salads, soups, and many other dishes. Many Asian fungi are commercially grown and have gained in popularity in the West. They are often available fresh in grocery stores and markets, including straw mushrooms (Volvariella volvacea), oyster mushrooms (Pleurotus ostreatus), shiitakes (Lentinula edodes), and enokitake (Flammulina spp.).
There are many more mushroom species that are harvested from the wild for personal consumption or commercial sale. Milk mushrooms, morels, chanterelles, truffles, black trumpets, and porcini mushrooms (Boletus edulis) (also known as king boletes) all demand a high price on the market. They are often used in gourmet dishes.
For certain types of cheeses, it is also a common practice to inoculate milk curds with fungal spores to foment the growth of specific species of mold that impart a unique flavor and texture to the cheese. This accounts for the blue colour in cheeses such as Stilton or Roquefort which is created using Penicillium roqueforti spores. Molds used in cheese production are usually non-toxic and are thus safe for human consumption; however, mycotoxins (e.g., aflatoxins, roquefortine C, patulin, or others) may accumulate due to fungal spoilage during cheese ripening or storage.
Many mushroom species are toxic to humans, with toxicities ranging from slight digestive problems or allergic reactions as well as hallucinations to severe organ failures and death. Some of the most deadly mushrooms belong to the genera Inocybe, Cortinarius, and most infamously, Amanita. The latter genus includes the destroying angel (A. virosa) and the death cap (A. phalloides), the most common cause of deadly mushroom poisoning. The false morel (Gyromitra esculenta) is considered a delicacy by some when cooked, yet can be highly toxic when eaten raw. Tricholoma equestre was considered edible until being implicated in some serious poisonings causing rhabdomyolysis.
Fly agaric mushrooms (A. muscaria) also cause occasional poisonings, mostly as a result of ingestion for use as a recreational drug for its hallucinogenic properties. Historically Fly agaric was used by Celtic Druids in Northern Europe and the Koryak people of north-eastern Siberia for religious or shamanic purposes. It is difficult to identify a safe mushroom without proper training and knowledge, thus it is often advised to assume that a mushroom in the wild is poisonous and not to consume it.
### Fungi in the biological control of pests
In agricultural settings, fungi that actively compete for nutrients and space with, and eventually prevail over, pathogenic microorganisms, such as bacteria or other fungi, via the competitive exclusion principle, or are parasites of these pathogens, may be beneficial agents for human use. For example, some fungi may be used to suppress growth or eliminate harmful plant pathogens, such as insects, mites, weeds, nematodes and other fungi that cause diseases of important crop plants. This has generated strong interest in the use and practical application of these fungi for the biological control of these agricultural pests. Entomopathogenic fungi can be used as biopesticides, as they actively kill insects. Examples of fungi that have been used as biological insecticides are Beauveria bassiana, Metarhizium anisopliae, Hirsutella spp, Paecilomyces spp, and Verticillium lecanii. Endophytic fungi of grasses of the genus Neotyphodium, such as N. coenophialum produce alkaloids that are toxic to a range of invertebrate and vertebrate herbivores. These alkaloids protect the infected grass plants from herbivory, but some endophyte alkaloids can cause poisoning of grazing animals, such as cattle and sheep. Infection of grass cultivars of turf or forage grasses with isolates of the grass endophytes that produce only specific alkaloids to improve grass hardiness and resistance to herbivores such as insects, while being non-toxic to livestock, is being used in grass breeding programs.
## Bioremediation
Certain fungi, in particular 'white rot' fungi, can degrade insecticides, herbicides, pentachlorophenol, creosote, coal tars, and heavy fuels and turn them into carbon dioxide, water, and basic elements. Research has recently discovered that fungi can be used to lock uranium into mineral form.
# Ecology
Although often inconspicuous, fungi occur in every environment on Earth and play very important roles in most ecosystems. Along with bacteria, fungi are the major decomposers in most terrestrial (and some aquatic) ecosystems, and therefore play a critical role in biogeochemical cycles and in many food webs. As decomposers, they play an indispensable role in nutrient cycling, especially as saprotrophs and symbionts, degrading organic matter to inorganic molecules, which can then re-enter anabolic metabolic pathways in plants or other organisms.
## Symbiosis
Many fungi have important symbiotic relationships with organisms from most if not all Kingdoms. These interactions can be mutualistic or antagonistic in nature, or in case of commensal fungi are of no apparent benefit or detriment to the host.
### With plants
Mycorrhizal symbiosis between plants and fungi is one of the most well-known plant-fungus associations and is of significant importance for plant growth and persistence in many ecosystems; over 90% of all plant species engage in some kind of mycorrhizal relationship with fungi and are dependent upon this relationship for survival. The mycorrhizal symbiosis is ancient, dating to at least 400 million years ago. It often increases the plant's uptake of inorganic compounds, such as nitrate and phosphate from soils having low concentrations of these key plant nutrients. In some mycorrhizal associations, the fungal partners may mediate plant-to-plant transfer of carbohydrates and other nutrients. Such mycorrhizal communities are called "common mycorrhizal networks".
Lichens are formed by a symbiotic relationship between algae or cyanobacteria (referred to in lichens as "photobionts") and fungi (mostly various species of ascomycetes and a few basidiomycetes), in which individual photobiont cells are embedded in a tissue formed by the fungus. As in mycorrhizas, the photobiont provides sugars and other carbohydrates, while the fungus provides minerals and water. The functions of both symbiotic organisms are so closely intertwined that they function almost as a single organism.
### With insects
Many insects also engage in mutualistic relationships with various types of fungi. Several groups of ants cultivate fungi in the order Agaricales as their primary food source, while ambrosia beetles cultivate various species of fungi in the bark of trees that they infest. Termites on the African Savannah are also known to cultivate fungi.
### As pathogens and parasites
However, many fungi are parasites on plants, animals (including humans), and other fungi. Serious fungal pathogens of many cultivated plants causing extensive damage and losses to agriculture and forestry include the rice blast fungus Magnaporthe oryzae, tree pathogens such as Ophiostoma ulmi and Ophiostoma novo-ulmi causing Dutch elm disease, and Cryphonectria parasitica responsible for chestnut blight, and plant-pathogenic fungi in the genera Fusarium, Ustilago, Alternaria, and Cochliobolus; fungi with the potential to cause serious human diseases, especially in persons with immuno-deficiencies, are in the genera Aspergillus, Candida, Cryptoccocus, Histoplasma, and Pneumocystis. Several pathogenic fungi are also responsible for relatively minor human diseases, such as athlete’s foot and ringworm. Some fungi are predators of nematodes, which they capture using an array of specialized structures, such as constricting rings or adhesive nets.
## Nutrition and possible autotrophy
Growth of fungi as hyphae on or in solid substrates or single cells in aquatic environments is adapted to efficient extraction of nutrients from these environments, because these growth forms have high surface area to volume ratios. These adaptations in morphology are complemented by hydrolytic enzymes secreted into the environment for digestion of large organic molecules, such as polysaccharides, proteins, lipids, and other organic substrates into smaller molecules. These molecules are then absorbed as nutrients into the fungal cells.
Traditionally, the fungi are considered heterotrophs, organisms that rely solely on carbon fixed by other organisms for metabolism. Fungi have evolved a remarkable metabolic versatility that allows many of them to use a large variety of organic substrates for growth, including simple compounds as nitrate, ammonia, acetate, or ethanol. Recent research raises the possibility that some fungi utilize the pigment melanin to extract energy from ionizing radiation, such as gamma radiation for "radiotrophic" growth. It has been proposed that this process might bear some similarity to photosynthesis in plants, but detailed biochemical data supporting the existence of this hypothetical pathway are presently lacking.
# Morphology
## Microscopic structures
Though fungi are part of the opisthokont clade, all phyla except for the chytrids have lost their posterior flagella. Fungi are unusual among the eukaryotes in having a cell wall that, besides glucans (e.g., β-1,3-glucan) and other typical components, contains the biopolymer chitin.
Many fungi grow as thread-like filamentous microscopic structures called hyphae, and an assemblage of intertwined and interconnected hyphae is called a mycelium. Hyphae can be septate, i.e., divided into hyphal compartments separated by a septum, each compartment containing one or more nuclei or can be coenocytic, i.e., lacking hyphal compartmentalization. However, septa have pores, such as the doliporus in the basidiomycetes that allow cytoplasm, organelles, and sometimes nuclei to pass through. Coenocytic hyphae are essentially multinucleate supercells. In some cases, fungi have developed specialized structures for nutrient uptake from living hosts; examples include haustoria in plant-parasitic fungi of nearly all divisions, and arbuscules of several mycorrhizal fungi, which penetrate into the host cells for nutrient uptake by the fungus.
## Macroscopic structures
Fungal mycelia can become visible macroscopically, for example, as concentric rings on various surfaces, such as damp walls, and on other substrates, such as spoilt food (see figure), and are commonly and generically called mould (American spelling, mold); fungal mycelia grown on solid agar media in laboratory petri dishes are usually referred to as colonies, with many species exhibiting characteristic macroscopic growth morphologies and colours, due to spores or pigmentation.
Specialized fungal structures important in sexual reproduction are the apothecia, perithecia, and cleistothecia in the ascomycetes, and the fruiting bodies of the basidiomycetes, and a few ascomycetes. These reproductive structures can sometimes grow very large, and are well known as mushrooms.
## Morphological and physiological features for substrate penetration
Fungal hyphae are specifically adapted to growth on solid surfaces and within substrates, and can exert astoundingly large penetrative mechanical forces. The plant pathogen, Magnaporthe grisea, forms a structure called an appressorium specifically designed for penetration of plant tissues, and the pressure generated by the appressorium, which is directed against the plant epidermis can exceed 8 MPa (80 bars). The generation of these mechanical pressures is the result of an interplay between physiological processes to increase intracellular turgor by production of osmolytes such as glycerol, and the morphology of the appressorium.
# Reproduction
Reproduction of fungi is complex, reflecting the heterogeneity in lifestyles and genetic make up within this group of organisms. Many fungi reproduce either sexually or asexually, depending on conditions in the environment. These conditions trigger genetically determined developmental programs leading to the expression of specialized structures for sexual or asexual reproduction. These structures aid both reproduction and efficient dissemination of spores or spore-containing propagules.
## Asexual reproduction
Asexual reproduction via vegetative spores or through mycelial fragmentation is common in many fungal species and allows more rapid dispersal than sexual reproduction. In the case of the "Fungi imperfecti" or Deuteromycota, which lack a sexual cycle, it is the only means of propagation. Asexual spores, upon germination, may found a population that is clonal to the population from which the spore originated, and thus colonize new environments.
## Sexual reproduction
Sexual reproduction with meiosis exists in all fungal phyla, except the Deuteromycota. It differs in many aspects from sexual reproduction in animals or plants. Many differences also exist between fungal groups and have been used to discriminate fungal clades and species based on morphological differences in sexual structures and reproductive strategies. Experimental crosses between fungal isolates can also be used to identify species based on biological species concepts. The major fungal clades have initially been delineated based on the morphology of their sexual structures and spores; for example, the spore-containing structures, asci and basidia, can be used in the identification of ascomycetes and basidiomycetes, respectively. Many fungal species have elaborate vegetative incompatibility systems that allow mating only between individuals of opposite mating type, while others can mate and sexually reproduce with any other individual or itself. Species of the former mating system are called heterothallic, and of the latter homothallic.
Most fungi have both a haploid and diploid stage in their life cycles. In all sexually reproducing fungi, compatible individuals combine by cell fusion of vegetative hyphae by anastomosis, required for the initiation of the sexual cycle. Ascomycetes and basidiomycetes go through a dikaryotic stage, in which the nuclei inherited from the two parents do not fuse immediately after cell fusion, but remain separate in the hyphal cells (see heterokaryosis).
In ascomycetes, dikaryotic hyphae of the hymenium form a characteristic hook at the hyphal septum. During cell division formation of the hook ensures proper distribution of the newly divided nuclei into the apical and basal hyphal compartments. An ascus (plural asci) is then formed, in which karyogamy (nuclear fusion) occurs. These asci are embedded in an ascocarp, or fruiting body, of the fungus. Karyogamy in the asci is followed immediately by meiosis and the production of ascospores. The ascospores are disseminated and germinate and may form a new haploid mycelium.
Sexual reproduction in basidiomycetes is similar to that of the ascomycetes. Compatible haploid hyphae fuse to produce a dikaryotic mycelium. However, the dikaryotic phase is more extensive in the basidiomycetes, in many cases also present in the vegetatively growing mycelium. A specialized anatomical structure, called a clamp connection, is formed at each hyphal septum. As with the structurally similar hook in the ascomycetes, formation of the clamp connection in the basidiomycetes is required for controlled transfer of nuclei during cell division, to maintain the dikaryotic stage with two genetically different nuclei in each hyphal compartment. A basidiocarp is formed in which club-like structures known as basidia generate haploid basidiospores after karyogamy and meiosis. The most commonly known basidiocarps are mushrooms, but they may also take many other forms (see Morphology section).
In zygomycetes, haploid hyphae of two individuals fuse, forming a zygote, which develops into a zygospore. When the zygospore germinates, it quickly undergoes meiosis, generating new haploid hyphae, which in turn may form asexual sporangiospores. These sporangiospores are means of rapid dispersal of the fungus and germinate into new genetically identical haploid fungal colonies, able to mate and undergo another sexual cycle followed by the generation of new zygospores, thus completing the lifecycle.
## Spore dispersal
Both asexual and sexual spores or sporangiospores of many fungal species are actively dispersed by forcible ejection from their reproductive structures. This ejection ensures exit of the spores from the reproductive structures as well as travelling through the air over long distances. Many fungi thereby possess specialized mechanical and physiological mechanisms as well as spore-surface structures, such as hydrophobins, for spore ejection. These mechanisms include, for example, forcible discharge of ascospores enabled by the structure of the ascus and accumulation of osmolytes in the fluids of the ascus that lead to explosive discharge of the ascospores into the air. The forcible discharge of single spores termed ballistospores involves formation of a small drop of water (Buller's drop), which upon contact with the spore leads to its projectile release with an initial acceleration of more than 10,000 g. Other fungi rely on alternative mechanisms for spore release, such as external mechanical forces, exemplified by puffballs. Attracting insects, such as flies, to fruiting structures, by virtue of their having lively colours and a putrid odour, for dispersal of fungal spores is yet another strategy, most prominently used by the stinkhorns.
## Other sexual processes
Besides regular sexual reproduction with meiosis, some fungal species may exchange genetic material via parasexual processes, initiated by anastomosis between hyphae and plasmogamy of fungal cells. The frequency and relative importance of parasexual events is unclear and may be lower than other sexual processes. However, it is known to play a role in intraspecific hybridization and is also likely required for hybridization between fungal species, which has been associated with major events in fungal evolution.
# Phylogeny and classification
For a long time taxonomists considered fungi to be members of the Plant Kingdom. This early classification was based mainly on similarities in lifestyle: both fungi and plant are mainly sessile, have similarities in general morphology and growth habitat (like plants, fungi often grow in soil, in the case of mushrooms forming conspicuous fruiting bodies, which sometimes bear resemblance to plants such as mosses). Moreover, both groups possess a cell wall, which is absent in the Animal Kingdom. However, the fungi are now considered a separate kingdom, distinct from both plants and animals, from which they appear to have diverged approximately one billion years ago. Many studies have identified several distinct morphological, biochemical, and genetic features in the Fungi, clearly delineating this group from the other kingdoms. For these reasons, the fungi are placed in their own kingdom.
## Physiological and morphological traits
Similar to animals and unlike most plants, fungi lack the capacity to synthesize organic carbon by chlorophyll-based photosynthesis; whereas plants store the reduced carbon as starch, fungi, like animals and some bacteria, use glycogen for storage of carbohydrates. A major component of the cell wall in many fungal species is the nitrogen-containing carbohydrate, chitin, also present in some animals, such as the insects and crustaceans, while the plant cell wall consists chiefly of the carbohydrate cellulose. The defining and unique characteristics of fungal cells include growth as hyphae, which are microscopic filaments of between 2-10 microns in diameter and up to several centimetres in length, and which combined form the fungal mycelium. Some fungi, such as yeasts, grow as single ovoid cells, similar to unicellular algae and the protists.
Unlike many plants, most fungi lack an efficient vascular system, such as xylem or phloem for long-distance transport of water and nutrients; as an example for convergent evolution, some fungi, such as Armillaria, form rhizomorphs or mycelial cords, resembling and functionally related to, but morphologically distinct from, plant roots.
Some characteristics shared between plants and fungi include the presence of vacuoles in the cell, and a similar pathway in the biosynthesis of terpenes using mevalonic acid and pyrophosphate as biochemical precursors; plants however use an additional terpene biosynthesis pathway in the chloroplasts that is apparently absent in fungi. Ancestral traits shared among members of the fungi include chitinous cell walls and heterotrophy by absorption. A further characteristic of the fungi that is absent from other eukaryotes, and shared only with some bacteria, is the biosynthesis of the amino acid, L-lysine, via the α-aminoadipate pathway.
Similar to plants, fungi produce a plethora of secondary metabolites functioning as defensive compounds or for niche adaptation; however, biochemical pathways for the synthesis of similar or even identical compounds often differ markedly between fungi and plants.
## Evolutionary history
The first organisms having features typical of fungi date to 1200, the Proterozoic. However, fungal fossils do not become common and uncontroversial until the early Devonian, when they are abundant in the Rhynie chert.
Even though traditionally included in many botany curricula and textbooks, fungi are now thought to be more closely related to animals than to plants and are placed with the animals in the monophyletic group of opisthokonts. For much of the Paleozoic Era, the fungi appear to have been aquatic, and consisted of organisms similar to the extant Chytrids in having flagellum-bearing spores. The early fossil record of the fungi is fragmentary, to say the least. The fungi probably colonized the land during the Cambrian, long before land plants. For some time after the Permian-Triassic extinction event, a fungal spike, originally thought to be an extraordinary abundance of fungal spores in sediments formed shortly after this event, suggested that they were the dominant life form during this period—nearly 100% of the fossil record available from this period. However, the relative proportion of fungal spores relative to spores formed by algal species is difficult to assess, the spike did not appear world-wide, and in many places it did not fall on the Permian-Triassic boundary.
Analyses using molecular phylogenetics support a monophyletic origin of the Fungi. The taxonomy of the Fungi is in a state of constant flux, especially due to recent research based on DNA comparisons. These current phylogenetic analyses often overturn classifications based on older and sometimes less discriminative methods based on morphological features and biological species concepts obtained from experimental matings.
There is no unique generally accepted system at the higher taxonomic levels and there are constant name changes at every level, from species upwards. However, efforts among fungal researchers are now underway to establish and encourage usage of a unified and more consistent nomenclature. Fungal species can also have multiple scientific names depending on its life cycle and mode (sexual or asexual) of reproduction. Web sites such as Index Fungorum and ITIS define preferred up-to-date names (with cross-references to older synonyms), but do not always agree with each other.
### Cladogram
## The taxonomic groups of fungi
The major divisions (phyla) of fungi have been classified based mainly on their sexual reproductive structures. Currently, seven fungal divisions are proposed:
- The Chytridiomycota are commonly known as chytrids. These fungi are ubiquitous with a worldwide distribution; chytrids produce zoospores that are capable of active movement through aqueous phases with a single flagellum. Consequently, some taxonomists had earlier classified them as protists on the basis of the flagellum. Molecular phylogenies, inferred from the rRNA-operon sequences representing the 18S, 28S, and 5.8S ribosomal subunits, suggest that the Chytrids are a basal fungal group divergent from the other fungal divisions, consisting of four major clades with some evidence for paraphyly or possibly polyphyly.
- The Blastocladiomycota were previously considered a taxonomic clade within the Chytridiomycota. Recent molecular data and ultrastructural characteristics, however, place the Blastocladiomycota as a sister clade to the Zygomycota, Glomeromycota, and Dikarya (Ascomycota and Basiomycota). The blastocladiomycetes are fungi that are saprotrophs and parasites of all eukaryotic groups and undergo sporic meiosis unlike their close relatives, the chytrids, which mostly exhibit zygotic meiosis.
- The Neocallimastigomycota were earlier placed in the phylum Chytridomycota. Members of this small phylum are anaerobic organisms, living in the digestive system of larger herbivorous mammals and possibly in other terrestrial and aquatic environments. They lack mitochondria but contain hydrogenosomes of mitochondrial origin. As the related chrytrids, neocallimastigomycetes form zoospores that are posteriorly uniflagellate or polyflagellate.
- The Zygomycota contain the taxa, Zygomycetes and Trichomycetes, and reproduce sexually with meiospores called zygospores and asexually with sporangiospores. Black bread mold (Rhizopus stolonifer) is a common species that belongs to this group; another is Pilobolus, which is capable of ejecting spores several meters through the air. Medically relevant genera include Mucor, Rhizomucor, and Rhizopus. Molecular phylogenetic investigation has shown the Zygomycota to be a polyphyletic phylum with evidence of paraphyly within this taxonomic group.
- Members of the Glomeromycota are fungi forming arbuscular mycorrhizae with higher plants. Only one species has been observed forming zygospores; all other species solely reproduce asexually. The symbiotic association between the Glomeromycota and plants is ancient, with evidence dating to 400 million years ago.
- The Ascomycota, commonly known as sac fungi or ascomycetes, constitute the largest taxonomic group within the Eumycota. These fungi form meiotic spores called ascospores, which are enclosed in a special sac-like structure called an ascus. This division includes morels, a few mushrooms and truffles, single-celled yeasts (e.g., of the genera Saccharomyces, Kluyveromyces, Pichia, and Candida), and many filamentous fungi living as saprotrophs, parasites, and mutualistic symbionts. Prominent and important genera of filamentous ascomycetes include Aspergillus, Penicillium, Fusarium, and Claviceps. Many ascomycetes species have only been observed undergoing asexual reproduction (called anamorphic species), but molecular data has often been able to identify their closest teleomorphs in the Ascomycota. Because the products of meiosis are retained within the sac-like ascus, several ascomyctes have been used for elucidating principles of genetics and heredity (e.g. Neurospora crassa).
- Members of the Basidiomycota, commonly known as the club fungi or basidiomycetes, produce meiospores called basidiospores on club-like stalks called basidia. Most common mushrooms belong to this group, as well as rust (fungus) and smut fungi, which are major pathogens of grains. Other important Basidiomyces include the maize pathogen,Ustilago maydis, human commensal species of the genus Malassezia, and the opportunistic human pathogen, Cryptococcus neoformans.
## Phylogenetic relationships with other fungus-like organisms
Because of some similarities in morphology and lifestyle, the slime molds (myxomycetes) and water molds (oomycetes) were formerly classified in the kingdom Fungi. Unlike true fungi, however, the cell walls of these organisms contain cellulose and lack chitin. Slime molds are unikonts like fungi, but are grouped in the Amoebozoa. Water molds are diploid bikonts, grouped in the Chromalveolate kingdom. Neither water molds nor slime molds are closely related to the true fungi, and, therefore, taxonomists no longer group them in the kingdom Fungi. Nonetheless, studies of the oomycetes and myxomycetes are still often included in mycology textbooks and primary research literature.
It has been suggested that the nucleariids, currently grouped in the Choanozoa, may be a sister group to the oomycete clade, and as such could be included in an expanded fungal kingdom. | Fungus
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
A fungus (Template:PronEng) is a eukaryotic organism that is a member of the kingdom Fungi (Template:PronEng).[2] The fungi are heterotrophic organisms possessing a chitinous cell wall. The majority of species grow as multicellular filaments called hyphae forming a mycelium; some fungal species also grow as single cells. Sexual and asexual reproduction of the fungi is commonly via spores, often produced on specialized structures or in fruiting bodies. Some species have lost the ability to form specialized reproductive structures, and propagate solely by vegetative growth. Yeasts, molds, and mushrooms are examples of fungi. The fungi are a monophyletic group that is phylogenetically clearly distinct from the morphologically similar slime molds (myxomycetes) and water molds (oomycetes). The fungi are more closely related to animals than plants, yet the discipline of biology devoted to the study of fungi, known as mycology, often falls under a branch of botany.
Occurring worldwide, most fungi are largely invisible to the naked eye, living for the most part in soil, dead matter, and as symbionts of plants, animals, or other fungi. They perform an essential role in all ecosystems in decomposing organic matter and are indispensable in nutrient cycling and exchange. Some fungi become noticeable when fruiting, either as mushrooms or molds. Many fungal species have long been used as a direct source of food, such as mushrooms and truffles and in fermentation of various food products, such as wine, beer, and soy sauce. More recently, fungi are being used as sources for antibiotics used in medicine and various enzymes, such as cellulases, pectinases, and proteases, important for industrial use or as active ingredients of detergents. Many fungi produce bioactive compounds called mycotoxins, such as alkaloids and polyketides that are toxic to animals including humans. Some fungi are used recreationally or in traditional ceremonies as a source of psychotropic compounds. Several species of the fungi are significant pathogens of humans and other animals, and losses due to diseases of crops (e.g., rice blast disease) or food spoilage caused by fungi can have a large impact on human food supply and local economies.
# Etymology and definition
The English word fungus is directly adopted from the Latin fungus, meaning "mushroom", used in Horace and Pliny.[3] This in turn is derived from the Greek word sphongos/σφογγος ("sponge"), referring to the macroscopic structures and morphology of some mushrooms and molds and also used in other languages (e.g., the German Schwamm ("sponge") or Schwammerl for some types of mushroom).
# Diversity
Fungi have a worldwide distribution, and grow in a wide range of habitats, including deserts. Most fungi grow in terrestrial environments, but several species occur only in aquatic habitats. Fungi along with bacteria are the primary decomposers of organic matter in most if not all terrestrial ecosystems worldwide. Based on observations of the ratio of the number of fungal species to the number of plant species in some environments, the fungal kingdom has been estimated to contain about 1.5 million species. [4] Around 70,000 fungal species have been formally described by taxonomists, but the true dimension of fungal diversity is still unknown. [5] Most fungi grow as thread-like filaments called hyphae, which form a mycelium, while others grow as single cells. [6][7] Until recently many fungal species were described based mainly on morphological characteristics, such as the size and shape of spores or fruiting structures, and biological species concepts; the application of molecular tools, such as DNA sequencing, to study fungal diversity has greatly enhanced the resolution and added robustness to estimates of diversity within various taxonomic groups.[8]
# Importance for human use
Human use of fungi for food preparation or preservation and other purposes is extensive and has a long history: yeasts are required for fermentation of beer, wine [9] and bread, some other fungal species are used in the production of soy sauce and tempeh. Mushroom farming and mushroom gathering are large industries in many countries. Many fungi are producers of antibiotics, including β-lactam antibiotics such as penicillin and cephalosporin.[10] Widespread use of these antibiotics for the treatment of bacterial diseases, such as tuberculosis, syphilis, leprosy, and many others began in the early 20th century and continues to play a major part in anti-bacterial chemotherapy. The study of the historical uses and sociological impact of fungi is known as ethnomycology.
### Cultured foods
Baker's yeast or Saccharomyces cerevisiae, a single-cell fungus, is used in the baking of bread and other wheat-based products, such as pizza and dumplings.[11] Several yeast species of the genus Saccharomyces are also used in the production of alcoholic beverages through fermentation.[12] Mycelial fungi, such as the shoyu koji mold (Aspergillus oryzae), are used in the brewing of Shoyu (soy sauce) and preparation of tempeh.[13] Quorn is a high-protein product made from the mold, Fusarium venenatum, and is used in vegetarian cooking.
### Other human uses
Fungi are also used extensively to produce industrial chemicals like lactic acid, antibiotics and even to make stonewashed jeans.[14] Several fungal species are ingested for their psychedelic properties, both recreationally and religiously (see main article, Psilocybin mushrooms).
### Mycotoxins
Many fungi produce compounds with biological activity. Several of these compounds are toxic and are therefore called mycotoxins, referring to their fungal origin and toxic activity. Of particular relevance to humans are those mycotoxins that are produced by moulds causing food spoilage and poisonous mushrooms (see below). Particularly infamous are the aflatoxins, which are insidious liver toxins and highly carcinogenic metabolites produced by Aspergillus species often growing in or on grains and nuts consumed by humans, and the lethal amatoxins produced by mushrooms of the genus Amanita. Other notable mycotoxins include ochratoxins, patulin, ergot alkaloids, and trichothecenes and fumonisins, all of which have significant impact on human food supplies or animal livestock. [15]
Mycotoxins belong to the group of secondary metabolites (or natural products). Originally, this group of compounds had been thought to be mere byproducts of primary metabolism, hence the name "secondary" metabolites. However, recent research has shown the existence of biochemical pathways solely for the purpose of producing mycotoxins and other natural products in fungi. [16] Mycotoxins provide a number of fitness benefits to the fungi that produce them in terms of physiological adaptation, competition with other microbes and fungi, and protection from fungivory. [17][18] These fitness benefits and the existence of dedicated biosynthetic pathways for mycotoxin production suggest that the mycotoxins are important for fungal persistence and survival.
### Edible and poisonous fungi
Some of the best known types of fungi are the edible and the poisonous mushrooms. Many species are commercially raised, but others must be harvested from the wild. Agaricus bisporus, sold as button mushrooms when small or Portobello mushrooms when larger, are the most commonly eaten species, used in salads, soups, and many other dishes. Many Asian fungi are commercially grown and have gained in popularity in the West. They are often available fresh in grocery stores and markets, including straw mushrooms (Volvariella volvacea), oyster mushrooms (Pleurotus ostreatus), shiitakes (Lentinula edodes), and enokitake (Flammulina spp.).
There are many more mushroom species that are harvested from the wild for personal consumption or commercial sale. Milk mushrooms, morels, chanterelles, truffles, black trumpets, and porcini mushrooms (Boletus edulis) (also known as king boletes) all demand a high price on the market. They are often used in gourmet dishes.
For certain types of cheeses, it is also a common practice to inoculate milk curds with fungal spores to foment the growth of specific species of mold that impart a unique flavor and texture to the cheese. This accounts for the blue colour in cheeses such as Stilton or Roquefort which is created using Penicillium roqueforti spores.[19] Molds used in cheese production are usually non-toxic and are thus safe for human consumption; however, mycotoxins (e.g., aflatoxins, roquefortine C, patulin, or others) may accumulate due to fungal spoilage during cheese ripening or storage.[20]
Many mushroom species are toxic to humans, with toxicities ranging from slight digestive problems or allergic reactions as well as hallucinations to severe organ failures and death. Some of the most deadly mushrooms belong to the genera Inocybe, Cortinarius, and most infamously, Amanita. The latter genus includes the destroying angel (A. virosa) and the death cap (A. phalloides), the most common cause of deadly mushroom poisoning. [21] The false morel (Gyromitra esculenta) is considered a delicacy by some when cooked, yet can be highly toxic when eaten raw. [22] Tricholoma equestre was considered edible until being implicated in some serious poisonings causing rhabdomyolysis. [23]
Fly agaric mushrooms (A. muscaria) also cause occasional poisonings, mostly as a result of ingestion for use as a recreational drug for its hallucinogenic properties. Historically Fly agaric was used by Celtic Druids in Northern Europe and the Koryak people of north-eastern Siberia for religious or shamanic purposes.[24] It is difficult to identify a safe mushroom without proper training and knowledge, thus it is often advised to assume that a mushroom in the wild is poisonous and not to consume it.
### Fungi in the biological control of pests
In agricultural settings, fungi that actively compete for nutrients and space with, and eventually prevail over, pathogenic microorganisms, such as bacteria or other fungi, via the competitive exclusion principle,[25] or are parasites of these pathogens, may be beneficial agents for human use. For example, some fungi may be used to suppress growth or eliminate harmful plant pathogens, such as insects, mites, weeds, nematodes and other fungi that cause diseases of important crop plants.[26] This has generated strong interest in the use and practical application of these fungi for the biological control of these agricultural pests. Entomopathogenic fungi can be used as biopesticides, as they actively kill insects.[27] Examples of fungi that have been used as biological insecticides are Beauveria bassiana, Metarhizium anisopliae, Hirsutella spp, Paecilomyces spp, and Verticillium lecanii.[28] [29] Endophytic fungi of grasses of the genus Neotyphodium, such as N. coenophialum produce alkaloids that are toxic to a range of invertebrate and vertebrate herbivores. These alkaloids protect the infected grass plants from herbivory, but some endophyte alkaloids can cause poisoning of grazing animals, such as cattle and sheep. [30] Infection of grass cultivars of turf or forage grasses with isolates of the grass endophytes that produce only specific alkaloids to improve grass hardiness and resistance to herbivores such as insects, while being non-toxic to livestock, is being used in grass breeding programs.[31]
## Bioremediation
Certain fungi, in particular 'white rot' fungi, can degrade insecticides, herbicides, pentachlorophenol, creosote, coal tars, and heavy fuels and turn them into carbon dioxide, water, and basic elements.[32] Research has recently discovered that fungi can be used to lock uranium into mineral form.[33]
# Ecology
Although often inconspicuous, fungi occur in every environment on Earth and play very important roles in most ecosystems. Along with bacteria, fungi are the major decomposers in most terrestrial (and some aquatic) ecosystems, and therefore play a critical role in biogeochemical cycles and in many food webs. As decomposers, they play an indispensable role in nutrient cycling, especially as saprotrophs and symbionts, degrading organic matter to inorganic molecules, which can then re-enter anabolic metabolic pathways in plants or other organisms.[34][35]
## Symbiosis
Many fungi have important symbiotic relationships with organisms from most if not all Kingdoms.[36][37][38] These interactions can be mutualistic or antagonistic in nature, or in case of commensal fungi are of no apparent benefit or detriment to the host. [39][40][41]
### With plants
Mycorrhizal symbiosis between plants and fungi is one of the most well-known plant-fungus associations and is of significant importance for plant growth and persistence in many ecosystems; over 90% of all plant species engage in some kind of mycorrhizal relationship with fungi and are dependent upon this relationship for survival.[42][43][44] The mycorrhizal symbiosis is ancient, dating to at least 400 million years ago.[45] It often increases the plant's uptake of inorganic compounds, such as nitrate and phosphate from soils having low concentrations of these key plant nutrients. In some mycorrhizal associations, the fungal partners may mediate plant-to-plant transfer of carbohydrates and other nutrients. Such mycorrhizal communities are called "common mycorrhizal networks". [46]
Lichens are formed by a symbiotic relationship between algae or cyanobacteria (referred to in lichens as "photobionts") and fungi (mostly various species of ascomycetes and a few basidiomycetes), in which individual photobiont cells are embedded in a tissue formed by the fungus.[47] As in mycorrhizas, the photobiont provides sugars and other carbohydrates, while the fungus provides minerals and water. The functions of both symbiotic organisms are so closely intertwined that they function almost as a single organism.
### With insects
Many insects also engage in mutualistic relationships with various types of fungi. Several groups of ants cultivate fungi in the order Agaricales as their primary food source, while ambrosia beetles cultivate various species of fungi in the bark of trees that they infest.[48] Termites on the African Savannah are also known to cultivate fungi.[49]
### As pathogens and parasites
However, many fungi are parasites on plants, animals (including humans), and other fungi. Serious fungal pathogens of many cultivated plants causing extensive damage and losses to agriculture and forestry include the rice blast fungus Magnaporthe oryzae,[50] tree pathogens such as Ophiostoma ulmi and Ophiostoma novo-ulmi causing Dutch elm disease,[51] and Cryphonectria parasitica responsible for chestnut blight, [52] and plant-pathogenic fungi in the genera Fusarium, Ustilago, Alternaria, and Cochliobolus; [40] fungi with the potential to cause serious human diseases, especially in persons with immuno-deficiencies, are in the genera Aspergillus, Candida, Cryptoccocus,[53][41][54] Histoplasma,[55] and Pneumocystis. [56] Several pathogenic fungi are also responsible for relatively minor human diseases, such as athlete’s foot and ringworm. Some fungi are predators of nematodes, which they capture using an array of specialized structures, such as constricting rings or adhesive nets.[57]
## Nutrition and possible autotrophy
Growth of fungi as hyphae on or in solid substrates or single cells in aquatic environments is adapted to efficient extraction of nutrients from these environments, because these growth forms have high surface area to volume ratios. These adaptations in morphology are complemented by hydrolytic enzymes secreted into the environment for digestion of large organic molecules, such as polysaccharides, proteins, lipids, and other organic substrates into smaller molecules. [58][59][60] These molecules are then absorbed as nutrients into the fungal cells.
Traditionally, the fungi are considered heterotrophs, organisms that rely solely on carbon fixed by other organisms for metabolism. Fungi have evolved a remarkable metabolic versatility that allows many of them to use a large variety of organic substrates for growth, including simple compounds as nitrate, ammonia, acetate, or ethanol.[61] [62] Recent research raises the possibility that some fungi utilize the pigment melanin to extract energy from ionizing radiation, such as gamma radiation for "radiotrophic" growth. [63] It has been proposed that this process might bear some similarity to photosynthesis in plants, [63] but detailed biochemical data supporting the existence of this hypothetical pathway are presently lacking.
# Morphology
## Microscopic structures
Though fungi are part of the opisthokont clade, all phyla except for the chytrids have lost their posterior flagella.[64] Fungi are unusual among the eukaryotes in having a cell wall that, besides glucans (e.g., β-1,3-glucan) and other typical components, contains the biopolymer chitin.[65]
Many fungi grow as thread-like filamentous microscopic structures called hyphae, and an assemblage of intertwined and interconnected hyphae is called a mycelium. [6] Hyphae can be septate, i.e., divided into hyphal compartments separated by a septum, each compartment containing one or more nuclei or can be coenocytic, i.e., lacking hyphal compartmentalization. However, septa have pores, such as the doliporus in the basidiomycetes that allow cytoplasm, organelles, and sometimes nuclei to pass through.[6] Coenocytic hyphae are essentially multinucleate supercells.[66] In some cases, fungi have developed specialized structures for nutrient uptake from living hosts; examples include haustoria in plant-parasitic fungi of nearly all divisions, and arbuscules of several mycorrhizal fungi,[67] which penetrate into the host cells for nutrient uptake by the fungus.
## Macroscopic structures
Fungal mycelia can become visible macroscopically, for example, as concentric rings on various surfaces, such as damp walls, and on other substrates, such as spoilt food (see figure), and are commonly and generically called mould (American spelling, mold); fungal mycelia grown on solid agar media in laboratory petri dishes are usually referred to as colonies, with many species exhibiting characteristic macroscopic growth morphologies and colours, due to spores or pigmentation.
Specialized fungal structures important in sexual reproduction are the apothecia, perithecia, and cleistothecia in the ascomycetes, and the fruiting bodies of the basidiomycetes, and a few ascomycetes. These reproductive structures can sometimes grow very large, and are well known as mushrooms.
## Morphological and physiological features for substrate penetration
Fungal hyphae are specifically adapted to growth on solid surfaces and within substrates, and can exert astoundingly large penetrative mechanical forces. The plant pathogen, Magnaporthe grisea, forms a structure called an appressorium specifically designed for penetration of plant tissues, and the pressure generated by the appressorium, which is directed against the plant epidermis can exceed 8 MPa (80 bars). [68] The generation of these mechanical pressures is the result of an interplay between physiological processes to increase intracellular turgor by production of osmolytes such as glycerol, and the morphology of the appressorium. [69]
# Reproduction
Reproduction of fungi is complex, reflecting the heterogeneity in lifestyles and genetic make up within this group of organisms. [6] Many fungi reproduce either sexually or asexually, depending on conditions in the environment. These conditions trigger genetically determined developmental programs leading to the expression of specialized structures for sexual or asexual reproduction. These structures aid both reproduction and efficient dissemination of spores or spore-containing propagules.
## Asexual reproduction
Asexual reproduction via vegetative spores or through mycelial fragmentation is common in many fungal species and allows more rapid dispersal than sexual reproduction. In the case of the "Fungi imperfecti" or Deuteromycota, which lack a sexual cycle, it is the only means of propagation. Asexual spores, upon germination, may found a population that is clonal to the population from which the spore originated, and thus colonize new environments.
## Sexual reproduction
Sexual reproduction with meiosis exists in all fungal phyla, except the Deuteromycota. It differs in many aspects from sexual reproduction in animals or plants. Many differences also exist between fungal groups and have been used to discriminate fungal clades and species based on morphological differences in sexual structures and reproductive strategies. Experimental crosses between fungal isolates can also be used to identify species based on biological species concepts. The major fungal clades have initially been delineated based on the morphology of their sexual structures and spores; for example, the spore-containing structures, asci and basidia, can be used in the identification of ascomycetes and basidiomycetes, respectively. Many fungal species have elaborate vegetative incompatibility systems that allow mating only between individuals of opposite mating type, while others can mate and sexually reproduce with any other individual or itself. Species of the former mating system are called heterothallic, and of the latter homothallic. [70]
Most fungi have both a haploid and diploid stage in their life cycles. In all sexually reproducing fungi, compatible individuals combine by cell fusion of vegetative hyphae by anastomosis, required for the initiation of the sexual cycle. Ascomycetes and basidiomycetes go through a dikaryotic stage, in which the nuclei inherited from the two parents do not fuse immediately after cell fusion, but remain separate in the hyphal cells (see heterokaryosis).
In ascomycetes, dikaryotic hyphae of the hymenium form a characteristic hook at the hyphal septum. During cell division formation of the hook ensures proper distribution of the newly divided nuclei into the apical and basal hyphal compartments. An ascus (plural asci) is then formed, in which karyogamy (nuclear fusion) occurs. These asci are embedded in an ascocarp, or fruiting body, of the fungus. Karyogamy in the asci is followed immediately by meiosis and the production of ascospores. The ascospores are disseminated and germinate and may form a new haploid mycelium.[71]
Sexual reproduction in basidiomycetes is similar to that of the ascomycetes. Compatible haploid hyphae fuse to produce a dikaryotic mycelium. However, the dikaryotic phase is more extensive in the basidiomycetes, in many cases also present in the vegetatively growing mycelium. A specialized anatomical structure, called a clamp connection, is formed at each hyphal septum. As with the structurally similar hook in the ascomycetes, formation of the clamp connection in the basidiomycetes is required for controlled transfer of nuclei during cell division, to maintain the dikaryotic stage with two genetically different nuclei in each hyphal compartment. [71] A basidiocarp is formed in which club-like structures known as basidia generate haploid basidiospores after karyogamy and meiosis.[72] The most commonly known basidiocarps are mushrooms, but they may also take many other forms (see Morphology section).
In zygomycetes, haploid hyphae of two individuals fuse, forming a zygote, which develops into a zygospore. When the zygospore germinates, it quickly undergoes meiosis, generating new haploid hyphae, which in turn may form asexual sporangiospores. These sporangiospores are means of rapid dispersal of the fungus and germinate into new genetically identical haploid fungal colonies, able to mate and undergo another sexual cycle followed by the generation of new zygospores, thus completing the lifecycle.
## Spore dispersal
Both asexual and sexual spores or sporangiospores of many fungal species are actively dispersed by forcible ejection from their reproductive structures. This ejection ensures exit of the spores from the reproductive structures as well as travelling through the air over long distances. Many fungi thereby possess specialized mechanical and physiological mechanisms as well as spore-surface structures, such as hydrophobins, for spore ejection. These mechanisms include, for example, forcible discharge of ascospores enabled by the structure of the ascus and accumulation of osmolytes in the fluids of the ascus that lead to explosive discharge of the ascospores into the air. [73] The forcible discharge of single spores termed ballistospores involves formation of a small drop of water (Buller's drop), which upon contact with the spore leads to its projectile release with an initial acceleration of more than 10,000 g. [74] Other fungi rely on alternative mechanisms for spore release, such as external mechanical forces, exemplified by puffballs. Attracting insects, such as flies, to fruiting structures, by virtue of their having lively colours and a putrid odour, for dispersal of fungal spores is yet another strategy, most prominently used by the stinkhorns.
## Other sexual processes
Besides regular sexual reproduction with meiosis, some fungal species may exchange genetic material via parasexual processes, initiated by anastomosis between hyphae and plasmogamy of fungal cells. The frequency and relative importance of parasexual events is unclear and may be lower than other sexual processes. However, it is known to play a role in intraspecific hybridization [75] and is also likely required for hybridization between fungal species, which has been associated with major events in fungal evolution. [76]
# Phylogeny and classification
For a long time taxonomists considered fungi to be members of the Plant Kingdom. This early classification was based mainly on similarities in lifestyle: both fungi and plant are mainly sessile, have similarities in general morphology and growth habitat (like plants, fungi often grow in soil, in the case of mushrooms forming conspicuous fruiting bodies, which sometimes bear resemblance to plants such as mosses). Moreover, both groups possess a cell wall, which is absent in the Animal Kingdom. However, the fungi are now considered a separate kingdom, distinct from both plants and animals, from which they appear to have diverged approximately one billion years ago.[77] Many studies have identified several distinct morphological, biochemical, and genetic features in the Fungi, clearly delineating this group from the other kingdoms. For these reasons, the fungi are placed in their own kingdom.
## Physiological and morphological traits
Similar to animals and unlike most plants, fungi lack the capacity to synthesize organic carbon by chlorophyll-based photosynthesis; whereas plants store the reduced carbon as starch, fungi, like animals and some bacteria, use glycogen [78] for storage of carbohydrates. A major component of the cell wall in many fungal species is the nitrogen-containing carbohydrate, chitin,[79] also present in some animals, such as the insects and crustaceans, while the plant cell wall consists chiefly of the carbohydrate cellulose. The defining and unique characteristics of fungal cells include growth as hyphae, which are microscopic filaments of between 2-10 microns in diameter and up to several centimetres in length, and which combined form the fungal mycelium. Some fungi, such as yeasts, grow as single ovoid cells, similar to unicellular algae and the protists.
Unlike many plants, most fungi lack an efficient vascular system, such as xylem or phloem for long-distance transport of water and nutrients; as an example for convergent evolution, some fungi, such as Armillaria, form rhizomorphs or mycelial cords,[80] resembling and functionally related to, but morphologically distinct from, plant roots.
Some characteristics shared between plants and fungi include the presence of vacuoles in the cell,[81] and a similar pathway in the biosynthesis of terpenes using mevalonic acid and pyrophosphate as biochemical precursors; plants however use an additional terpene biosynthesis pathway in the chloroplasts that is apparently absent in fungi.[82] Ancestral traits shared among members of the fungi include chitinous cell walls and heterotrophy by absorption.[71] A further characteristic of the fungi that is absent from other eukaryotes, and shared only with some bacteria, is the biosynthesis of the amino acid, L-lysine, via the α-aminoadipate pathway. [83]
Similar to plants, fungi produce a plethora of secondary metabolites functioning as defensive compounds or for niche adaptation; however, biochemical pathways for the synthesis of similar or even identical compounds often differ markedly between fungi and plants. [84][85]
## Evolutionary history
The first organisms having features typical of fungi date to 1200, the Proterozoic.[86] However, fungal fossils do not become common and uncontroversial until the early Devonian, when they are abundant in the Rhynie chert.[87]
Even though traditionally included in many botany curricula and textbooks, fungi are now thought to be more closely related to animals than to plants and are placed with the animals in the monophyletic group of opisthokonts.[71] For much of the Paleozoic Era, the fungi appear to have been aquatic, and consisted of organisms similar to the extant Chytrids in having flagellum-bearing spores.[88] The early fossil record of the fungi is fragmentary, to say the least. The fungi probably colonized the land during the Cambrian, long before land plants.[87] For some time after the Permian-Triassic extinction event, a fungal spike, originally thought to be an extraordinary abundance of fungal spores in sediments formed shortly after this event, suggested that they were the dominant life form during this period—nearly 100% of the fossil record available from this period.[89] However, the relative proportion of fungal spores relative to spores formed by algal species is difficult to assess, [90] the spike did not appear world-wide, [91][92] and in many places it did not fall on the Permian-Triassic boundary.[93]
Analyses using molecular phylogenetics support a monophyletic origin of the Fungi.[8] The taxonomy of the Fungi is in a state of constant flux, especially due to recent research based on DNA comparisons. These current phylogenetic analyses often overturn classifications based on older and sometimes less discriminative methods based on morphological features and biological species concepts obtained from experimental matings.[94][95]
There is no unique generally accepted system at the higher taxonomic levels and there are constant name changes at every level, from species upwards. However, efforts among fungal researchers are now underway to establish and encourage usage of a unified and more consistent nomenclature.[8] Fungal species can also have multiple scientific names depending on its life cycle and mode (sexual or asexual) of reproduction. Web sites such as Index Fungorum and ITIS define preferred up-to-date names (with cross-references to older synonyms), but do not always agree with each other.
### Cladogram
Template:Clade
## The taxonomic groups of fungi
The major divisions (phyla) of fungi have been classified based mainly on their sexual reproductive structures. Currently, seven fungal divisions are proposed:[8]
- The Chytridiomycota are commonly known as chytrids. These fungi are ubiquitous with a worldwide distribution; chytrids produce zoospores that are capable of active movement through aqueous phases with a single flagellum. Consequently, some taxonomists had earlier classified them as protists on the basis of the flagellum. Molecular phylogenies, inferred from the rRNA-operon sequences representing the 18S, 28S, and 5.8S ribosomal subunits, suggest that the Chytrids are a basal fungal group divergent from the other fungal divisions, consisting of four major clades with some evidence for paraphyly or possibly polyphyly. [88]
- The Blastocladiomycota were previously considered a taxonomic clade within the Chytridiomycota. Recent molecular data and ultrastructural characteristics, however, place the Blastocladiomycota as a sister clade to the Zygomycota, Glomeromycota, and Dikarya (Ascomycota and Basiomycota). The blastocladiomycetes are fungi that are saprotrophs and parasites of all eukaryotic groups and undergo sporic meiosis unlike their close relatives, the chytrids, which mostly exhibit zygotic meiosis. [88]
- The Neocallimastigomycota were earlier placed in the phylum Chytridomycota. Members of this small phylum are anaerobic organisms, living in the digestive system of larger herbivorous mammals and possibly in other terrestrial and aquatic environments. They lack mitochondria but contain hydrogenosomes of mitochondrial origin. As the related chrytrids, neocallimastigomycetes form zoospores that are posteriorly uniflagellate or polyflagellate.[8]
- The Zygomycota contain the taxa, Zygomycetes and Trichomycetes, and reproduce sexually with meiospores called zygospores and asexually with sporangiospores. Black bread mold (Rhizopus stolonifer) is a common species that belongs to this group; another is Pilobolus, which is capable of ejecting spores several meters through the air. Medically relevant genera include Mucor, Rhizomucor, and Rhizopus. Molecular phylogenetic investigation has shown the Zygomycota to be a polyphyletic phylum with evidence of paraphyly within this taxonomic group. [96]
- Members of the Glomeromycota are fungi forming arbuscular mycorrhizae with higher plants. Only one species has been observed forming zygospores; all other species solely reproduce asexually. The symbiotic association between the Glomeromycota and plants is ancient, with evidence dating to 400 million years ago.[45]
- The Ascomycota, commonly known as sac fungi or ascomycetes, constitute the largest taxonomic group within the Eumycota. These fungi form meiotic spores called ascospores, which are enclosed in a special sac-like structure called an ascus. This division includes morels, a few mushrooms and truffles, single-celled yeasts (e.g., of the genera Saccharomyces, Kluyveromyces, Pichia, and Candida), and many filamentous fungi living as saprotrophs, parasites, and mutualistic symbionts. Prominent and important genera of filamentous ascomycetes include Aspergillus, Penicillium, Fusarium, and Claviceps. Many ascomycetes species have only been observed undergoing asexual reproduction (called anamorphic species), but molecular data has often been able to identify their closest teleomorphs in the Ascomycota. Because the products of meiosis are retained within the sac-like ascus, several ascomyctes have been used for elucidating principles of genetics and heredity (e.g. Neurospora crassa).
- Members of the Basidiomycota, commonly known as the club fungi or basidiomycetes, produce meiospores called basidiospores on club-like stalks called basidia. Most common mushrooms belong to this group, as well as rust (fungus) and smut fungi, which are major pathogens of grains. Other important Basidiomyces include the maize pathogen,Ustilago maydis, human commensal species of the genus Malassezia, and the opportunistic human pathogen, Cryptococcus neoformans.
## Phylogenetic relationships with other fungus-like organisms
Because of some similarities in morphology and lifestyle, the slime molds (myxomycetes) and water molds (oomycetes) were formerly classified in the kingdom Fungi. Unlike true fungi, however, the cell walls of these organisms contain cellulose and lack chitin. Slime molds are unikonts like fungi, but are grouped in the Amoebozoa. Water molds are diploid bikonts, grouped in the Chromalveolate kingdom. Neither water molds nor slime molds are closely related to the true fungi, and, therefore, taxonomists no longer group them in the kingdom Fungi. Nonetheless, studies of the oomycetes and myxomycetes are still often included in mycology textbooks and primary research literature.
It has been suggested that the nucleariids, currently grouped in the Choanozoa, may be a sister group to the oomycete clade, and as such could be included in an expanded fungal kingdom.[97] | https://www.wikidoc.org/index.php/Fungal | |
5c8da8ef8541351b83a08ad9c227d18f27f1378b | wikidoc | G-Spot | G-Spot
# Overview
The Gräfenberg spot, or G-spot, is an erogenous zone that when stimulated leads to high levels of sexual arousal and powerful orgasms.
# Origin and popularity of the term
The term "G-spot" was coined by Addiego et al. in 1981. It is named after the German gynaecologist Ernst Gräfenberg who first hypothesized its existence in 1944. The G-spot's existence was not disclosed until the next year, with the publication of The G Spot and Other Recent Discoveries About Human Sexuality by Ladas et. al. Shortly after publication of Ladas's book, many gynaecologists publicly criticized its scholarship and accuracy..
## Location of the spot
The purported location of the G-spot has changed over time. Two primary methods have been used to attempt to locate it:
- The first is based on self-reported levels of arousal during stimulation and
- the second based on the claim that stimulation of the G-spot leads to female ejaculation.
One of the studies using self-reported levels of arousal was a case study with a single woman who claimed the experience of a “deeper” orgasm when her G-spot was stimulated. In the published study it was reported that stimulation of the anterior vaginal wall made the area grow by fifty percent.
Another study examined eleven women in an attempt to locate the spot under laboratory conditions. Researchers attempted to find the G-spot by “palpating the entire vagina in a clockwise fashion.” Using this technique the researchers reported discovering that four of the women had highly sensitive areas on the anterior vaginal wall.
## Public belief
Despite professional and scientific criticism and skepticism, the G-spot, as a concept, was widely accepted by the public. One study reports that 84 percent of women believe that there is a “highly sensitive area” in the vagina. Most popular sexology books treat the G-spot as real.
## Scientific evidence
Subsequent empirical investigations of the G-spot have yielded variable results. Tests that examined the vaginal wall innervation show there is no one area with a greater density of nerve endings. A recent study of 110 biopsy specimens drawn from 21 women concluded with the absence of a vaginal locus with greater nerve density. G-spot proponents are criticized for placing too much credence upon anecdotal evidence from women.
The few studies attempting to locate the G-spot more precisely have yielded positive evidence, yet only from small participant samples, and have been criticized for the use of questionable investigation methods.. A recent ultrasonography study reported that women who claimed to experience vaginal orgasm were statistically more likely to have thicker tissue in the anterior vaginal wall.
# The Skene's Glands
Other researchers have attempted to locate the G-spot by building on the claim that G-spot stimulation leads to female ejaculation. Tepper hypothesized that non-urine female ejaculate originated from the female paraurethral glands, or Skene's gland. In their study they examined tissue from 18 patients and demonstrated that 15 showed prostate-specific antigens.
More recent studies have backed up this finding, leading some to call the Skene's glands the female prostate. This finding has been used to claim that the G-spot is actually a system of glands and ducts that surround the urethra. This system is located within the anterior (front) wall of the vagina, about one centimeter from the surface and one third to one-half the way in from the vaginal opening.
In July 2002, Emmanuele Jannini of the University of Aquila, Italy discovered PDE5 activity in the area of the G-spot and speculated that the absence of G-spot orgasms is connected to the lack of Skene's glands in some women. In such women, concentrations of PDE5 were much lower.
However, most researchers feel that the connection between the Skene's Gland and the G-spot is weak. The Skene's Gland does not seem to have receptors for touch stimulation and no direct evidence for its involvement has been forthcoming.
Strong evidence for the existence of the G Spot was reported by Ian Sample, science correspondent for the British newspaper The Guardian, in the Thursday February 21 2008 edition. The following is a quote from that newspaper article: "Doctors claim to have found the first compelling evidence that the G spot exists, but say not all women appear to have one.
Ultrasound scans revealed clear anatomical differences between women who said they experienced vaginal orgasms and a group of women who did not. The scans identified a region of thicker tissue where the G spot was rumoured to be lurking, which was not visible in the women who had never had a vaginal orgasm.
Doctors at the University of L'Aquila in Italy, where the study was conducted, say the findings make it possible for women to have a rapid test to confirm whether or not they have a G spot.
The location, and even existence, of the G spot has been hotly contested in medical circles. While doctors know that female sexual anatomy varies substantially, until now there has been no solid evidence to link those differences to a woman's sexual responses.
"For the first time, it is possible to determine by a simple, rapid and inexpensive method if a woman has a G spot or not," Dr Emmanuele Jannini told New Scientist magazine.
The G spot is only thought to affect a woman's ability to have vaginal orgasms, so if women do not have one "they can still have a normal orgasm through stimulation of the clitoris," Jannini said.
# Relation with the urethral sponge
Some claim that the urethral sponge is the same as the G-spot. | G-Spot
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
# Overview
The Gräfenberg spot, or G-spot, is an erogenous zone that when stimulated leads to high levels of sexual arousal and powerful orgasms.[1]
# Origin and popularity of the term
The term "G-spot" was coined by Addiego et al. in 1981.[2] It is named after the German gynaecologist Ernst Gräfenberg who first hypothesized its existence in 1944. The G-spot's existence was not disclosed until the next year, with the publication of The G Spot and Other Recent Discoveries About Human Sexuality by Ladas et. al.[1] Shortly after publication of Ladas's book, many gynaecologists publicly criticized its scholarship and accuracy.[3].
## Location of the spot
The purported location of the G-spot has changed over time. Two primary methods have been used to attempt to locate it:[4]
- The first is based on self-reported levels of arousal during stimulation and
- the second based on the claim that stimulation of the G-spot leads to female ejaculation.
One of the studies using self-reported levels of arousal was a case study with a single woman who claimed the experience of a “deeper” orgasm when her G-spot was stimulated. In the published study it was reported that stimulation of the anterior vaginal wall made the area grow by fifty percent.[2]
Another study examined eleven women in an attempt to locate the spot under laboratory conditions. Researchers attempted to find the G-spot by “palpating the entire vagina in a clockwise fashion.” Using this technique the researchers reported discovering that four of the women had highly sensitive areas on the anterior vaginal wall.[5]
## Public belief
Despite professional and scientific criticism and skepticism, the G-spot, as a concept, was widely accepted by the public. One study reports that 84 percent of women believe that there is a “highly sensitive area” in the vagina. Most popular sexology books treat the G-spot as real.[6]
## Scientific evidence
Subsequent empirical investigations of the G-spot have yielded variable results.[4] Tests that examined the vaginal wall innervation show there is no one area with a greater density of nerve endings. A recent study of 110 biopsy specimens drawn from 21 women concluded with the absence of a vaginal locus with greater nerve density.[7] G-spot proponents are criticized for placing too much credence upon anecdotal evidence from women.[4]
The few studies attempting to locate the G-spot more precisely have yielded positive evidence, yet only from small participant samples, and have been criticized for the use of questionable investigation methods.[4]. A recent ultrasonography study reported that women who claimed to experience vaginal orgasm were statistically more likely to have thicker tissue in the anterior vaginal wall. [8]
# The Skene's Glands
Other researchers have attempted to locate the G-spot by building on the claim that G-spot stimulation leads to female ejaculation. Tepper hypothesized that non-urine female ejaculate originated from the female paraurethral glands, or Skene's gland.[9] In their study they examined tissue from 18 patients and demonstrated that 15 showed prostate-specific antigens.
More recent studies have backed up this finding, leading some to call the Skene's glands the female prostate.[10] This finding has been used to claim that the G-spot is actually a system of glands and ducts that surround the urethra. This system is located within the anterior (front) wall of the vagina, about one centimeter from the surface and one third to one-half the way in from the vaginal opening.[11]
In July 2002, Emmanuele Jannini of the University of Aquila, Italy discovered PDE5 activity in the area of the G-spot and speculated that the absence of G-spot orgasms is connected to the lack of Skene's glands in some women. In such women, concentrations of PDE5 were much lower.[12]
However, most researchers feel that the connection between the Skene's Gland and the G-spot is weak.[4][13] The Skene's Gland does not seem to have receptors for touch stimulation and no direct evidence for its involvement has been forthcoming.[14]
Strong evidence for the existence of the G Spot was reported by Ian Sample, science correspondent for the British newspaper The Guardian, in the Thursday February 21 2008 edition. The following is a quote from that newspaper article: "Doctors claim to have found the first compelling evidence that the G spot exists, but say not all women appear to have one.
Ultrasound scans revealed clear anatomical differences between women who said they experienced vaginal orgasms and a group of women who did not. The scans identified a region of thicker tissue where the G spot was rumoured to be lurking, which was not visible in the women who had never had a vaginal orgasm.
Doctors at the University of L'Aquila in Italy, where the study was conducted, say the findings make it possible for women to have a rapid test to confirm whether or not they have a G spot.
The location, and even existence, of the G spot has been hotly contested in medical circles. While doctors know that female sexual anatomy varies substantially, until now there has been no solid evidence to link those differences to a woman's sexual responses.
"For the first time, it is possible to determine by a simple, rapid and inexpensive method if a woman has a G spot or not," Dr Emmanuele Jannini told New Scientist magazine.
The G spot is only thought to affect a woman's ability to have vaginal orgasms, so if women do not have one "they can still have a normal orgasm through stimulation of the clitoris," Jannini said.
# Relation with the urethral sponge
Some claim that the urethral sponge is the same as the G-spot.[15] | https://www.wikidoc.org/index.php/G-Spot | |
041598787ee73080cf4f31690735189d860a3207 | wikidoc | G cell | G cell
# Overview
In anatomy, the G cell is a type of cell in the stomach that secretes gastrin. It works in conjunction with gastric chief cells and parietal cells.
G cells are found deep with the gastric glands of the stomach antrum, and occasionally in the pancreas.
The vagus nerve innervates the G cells.
Gastrin-releasing peptide is released by the post-ganglionic fibers of the vagus nerve onto G cells during parasympathetic stimulation.
Gastrin-releasing peptide, as well as the presence of amino acids in the stomach, stimulate the release of gastrin from the G cells. Gastrin stimulates enterochromaffin cells to release histamine.
Gastrin also targets parietal cells.
The increase of histamine and the direct stimulation by gastrin, cause parietal cells to increase HCl secretion in the stomach. | G cell
# Overview
In anatomy, the G cell is a type of cell in the stomach that secretes gastrin.[1] It works in conjunction with gastric chief cells and parietal cells.
G cells are found deep with the gastric glands of the stomach antrum, and occasionally in the pancreas.[2]
The vagus nerve innervates the G cells.
Gastrin-releasing peptide is released by the post-ganglionic fibers of the vagus nerve onto G cells during parasympathetic stimulation.
Gastrin-releasing peptide, as well as the presence of amino acids in the stomach, stimulate the release of gastrin from the G cells. Gastrin stimulates enterochromaffin cells to release histamine.
Gastrin also targets parietal cells.
The increase of histamine and the direct stimulation by gastrin, cause parietal cells to increase HCl secretion in the stomach. | https://www.wikidoc.org/index.php/G-cells | |
9cbf0d2f76075c0d9ecbf93f4899803927658f0d | wikidoc | G-spot | G-spot
The Gräfenberg spot, or G-spot, is debatedly a small area in women behind the pubic bone, surrounding the urethra and accessible through the anterior wall of the vagina. It is putatively an erogenous zone that when stimulated leads to high levels of sexual arousal and powerful orgasms.
There is a great deal of dispute about the reality of the G-spot in the scientific community. Most of the strong support for the claim comes from books aimed at a popular audience.
The term "G-spot" was coined by Addiego et al. in 1981. It is named after the German gynaecologist Ernst Gräfenberg who is claimed to have first hypothesized the existence of such an area in 1950. The G-spot didn't enter public consciousness until a year later with the publication of the book “The G Spot and Other Recent Discoveries About Human Sexuality.”
Shortly after the publication of Ladas' book many professional gynaecologists publicly criticized its scholarship and accuracy.
# Search for the G-Spot
The purported location of the G-spot has changed over time. Two primary methods have been used to attempt to locate it. The first is based on self-reported levels of arousal during stimulation and the second based on the claim that stimulation of the G-spot leads to female ejaculation. One of the studies using self-reported levels of arousal was a case study with a single woman who claimed the experience of a “deeper” orgasm when her G-spot was stimulated. In the published study it was reported that stimulation of the anterior vaginal wall made the area grow by fifty percent. Another study examined eleven women in an attempt to locate the spot under laboratory conditions. Researchers attempted to find the G-spot by “palpating the entire vagina in a clockwise fashion.” Using this technique the researchers reported discovering that four of the women had highly sensitive areas on the anterior vaginal wall.
Immediately after publication of Ladas et. al's book professional gynaecologists were skeptical of the reality of the G-spot. In a 1983 Time Magazine article about the G-spot and recent book, Dr. J. Jones Stewart, a gynaecologist was quoted as saying all evidence pointed to the fact that there was no G-spot. Specifically he pointed out that women that had the area (that supposedly contained the g-spot) surgically removed, reported no loss of sensation.
Despite professional and scientific criticism and skepticism the concept of a G-spot was met with wide-spread acceptance in the public. One study reports that 84 percent of women believe that there is a “highly sensitive area” in the vagina. Most popular books on sexuality discuss the G-spot as a reality.
However, to date, all attempts of scientific or empirical investigation into the reality of the G-spot have turned up nothing or highly questionable results. Tests that examined the innervation of the vaginal wall show that there is no area that has an increased number of nerve endings. A recent study investigating 110 biopsy specimens from 21 women concluded the absence of vaginal location with increased nerve density . Proponents are also criticized for putting too much reliance on anecdotal evidence. The few studies that have tried to locate it using more precise means have mostly turned up no results. The few that have returned positive evidence are criticized for using small sample sizes and questionable methods.
# The Skene's Glands
Other researchers have attempted to locate the G-spot by building on the claim that G-spot stimulation leads to female ejaculation. Tepper hypothesized that non-urine female ejaculate originated from the female paraurethral glands, or Skene's gland. In their study they examined tissue from 18 patients and demonstrated that 15 showed prostate-specific antigens. More recent studies have backed up this finding leading some to call the Skene's glands "the female prostate". This find has been used to claim that the G-spot is actually “a system of glands and ducts that surround the urethra” which is located “within the anterior wall of the vagina, about one centimeter from the surface and one third to one-half the way in from the vaginal opening.”
In July 2002 Emmanuele Jannini of the University of Aquila, Italy discovered PDE5 activity in the area of the g-spot and speculated that the absence of g-spot orgasms is connected to the lack of Skene's glands in some women. In such women concentrations of PDE5 were much lower.
However most researchers feel that the connection between the Skene's Gland and the g-spot is weak. The Skene's Gland does not seem to have receptors for touch stimulation and no direct evidence for its involvement has been forthcoming. | G-spot
The Gräfenberg spot, or G-spot, is debatedly a small area in women behind the pubic bone, surrounding the urethra and accessible through the anterior wall of the vagina. It is putatively an erogenous zone that when stimulated leads to high levels of sexual arousal and powerful orgasms.[1]
There is a great deal of dispute about the reality of the G-spot in the scientific community. Most of the strong support for the claim comes from books aimed at a popular audience.[2]
The term "G-spot" was coined by Addiego et al.[3] in 1981. It is named after the German gynaecologist Ernst Gräfenberg who is claimed to have first hypothesized the existence of such an area in 1950. The G-spot didn't enter public consciousness until a year later with the publication of the book “The G Spot and Other Recent Discoveries About Human Sexuality.”[1]
Shortly after the publication of Ladas' book many professional gynaecologists publicly criticized its scholarship and accuracy.[4]
# Search for the G-Spot
The purported location of the G-spot has changed over time. Two primary methods have been used to attempt to locate it. The first is based on self-reported levels of arousal during stimulation and the second based on the claim that stimulation of the G-spot leads to female ejaculation.[2] One of the studies using self-reported levels of arousal was a case study with a single woman who claimed the experience of a “deeper” orgasm when her G-spot was stimulated. In the published study it was reported that stimulation of the anterior vaginal wall made the area grow by fifty percent.[3] Another study examined eleven women in an attempt to locate the spot under laboratory conditions. Researchers attempted to find the G-spot by “palpating the entire vagina in a clockwise fashion.” Using this technique the researchers reported discovering that four of the women had highly sensitive areas on the anterior vaginal wall.[5]
Immediately after publication of Ladas et. al's book professional gynaecologists were skeptical of the reality of the G-spot. In a 1983 Time Magazine article about the G-spot and recent book, Dr. J. Jones Stewart, a gynaecologist was quoted as saying all evidence pointed to the fact that there was no G-spot. Specifically he pointed out that women that had the area (that supposedly contained the g-spot) surgically removed, reported no loss of sensation.
Despite professional and scientific criticism and skepticism the concept of a G-spot was met with wide-spread acceptance in the public. One study reports that 84 percent of women believe that there is a “highly sensitive area” in the vagina. Most popular books on sexuality discuss the G-spot as a reality.[6]
However, to date, all attempts of scientific or empirical investigation into the reality of the G-spot have turned up nothing or highly questionable results.[2] Tests that examined the innervation of the vaginal wall show that there is no area that has an increased number of nerve endings. A recent study investigating 110 biopsy specimens from 21 women concluded the absence of vaginal location with increased nerve density [7]. Proponents are also criticized for putting too much reliance on anecdotal evidence.[2] The few studies that have tried to locate it using more precise means have mostly turned up no results. The few that have returned positive evidence are criticized for using small sample sizes and questionable methods.[2]
# The Skene's Glands
Other researchers have attempted to locate the G-spot by building on the claim that G-spot stimulation leads to female ejaculation. Tepper[8] hypothesized that non-urine female ejaculate originated from the female paraurethral glands, or Skene's gland. In their study they examined tissue from 18 patients and demonstrated that 15 showed prostate-specific antigens. More recent studies have backed up this finding[9] leading some to call the Skene's glands "the female prostate". This find has been used to claim that the G-spot is actually “a system of glands and ducts that surround the urethra” which is located “within the anterior wall of the vagina, about one centimeter from the surface and one third to one-half the way in from the vaginal opening.”[10]
In July 2002 Emmanuele Jannini of the University of Aquila, Italy discovered PDE5 activity in the area of the g-spot and speculated that the absence of g-spot orgasms is connected to the lack of Skene's glands in some women. In such women concentrations of PDE5 were much lower.[11]
However most researchers feel that the connection between the Skene's Gland and the g-spot is weak.[2][12] The Skene's Gland does not seem to have receptors for touch stimulation and no direct evidence for its involvement has been forthcoming.[13] | https://www.wikidoc.org/index.php/G-spot | |
7b0bf767d90da82dbab8c3c3b2eb4565a23dc2fb | wikidoc | GABRA2 | GABRA2
Gamma-aminobutyric acid receptor subunit alpha-2 is a protein in humans that is encoded by the GABRA2 gene.
GABRA2 is an alpha subunit that is part of GABA-A receptors, which are ligand-gated chloride channels and are activated by the major inhibitory neurotransmitter in the mammalian brain, GABA. Chloride conductance of these channels can be modulated by agents, such as benzodiazepines (psychoactive drugs) that bind to the GABA-A receptor.
GABA-A receptors are composed of two alpha, two beta, and one gamma subunits. They have at least 16 distinct subunits identified, including GABRA2. This receptor is found mainly in specific regions of the brain, such as the hippocampus.
Subunit isoforms are seen around in various locations in the brain throughout growth. The combination of subunits has a large effect on the pharmacological and biophysical characteristics. GABRA2 has been found to mediate anxiolytic activity, which plays a key role in emotional and behavioral control. Most of GABRA2 modifications have been found to be linked to alcoholism and adolescent behavior.
# Structure
GABRA2 is one of the 16 distinct alpha subunits found for the GABA receptor. GABA-A has a pentametric form, with two alpha, two beta, and one gamma subunit. The various subunit isoforms seen in the GABA-A receptor structure has an effect on its function. GABRA2 is most often seen as part of the most common expression α2β3γ2, which is seen in 13% of all GABA-A receptors. The subunit, GABRA2, is found primarily in hippocampus and/or the forebrain. It is more confined to areas of the brain in comparison to other alpha subunits seen in GABA-A receptors. It is present in 35% of all GABA-A receptors being the fourth most abundant subunit next to GABRA1 and various beta subunits. Like all subunits, it is made from structurally distinct proteins. The presence of this subunit causes an easier binding of benzodiazepine which is a category of psychoactive drugs.
# Function
GABRA2 mediates neural activity necessary for information processing in inter-neurons. GABRA2 participates in transporting Cl− ions into the membrane, since it forms part of the GABA-A receptor. The influx of Cl− causes the hyper-polarization of the membrane, leading to inhibitory actions.
GABRA2 increases the risk of anxiety making it a target for treating behavioral disorders. Some examples of behavioral disorders include anxiety, alcohol dependence, and drug use. GABRA2 is a binding site for benzodiazepines. Benzodiazepines are psychoactive drugs known to reduce anxiety. Benzodiazepines bind to GABRA2 causing chloride channels to open, leading to the hyper-polarization of the membrane. Other anxiolytic drugs like Diazepam target this alpha subunit in GABA-A to induce inhibitory effects.
GABRA2 is associated with reward behavior when it activates the insula. The insula is part of the cerebral cortex responsible for emotions. GABRA2 role in reward behavior explains the higher risk of alcohol dependence and drug use behavior.
# Clinical Significance
Since GABRA 2 mediates anxiolytic activity, it is a key receptor for emotional control. Several developmental stages of GABRA2 have shown effects on behavior such as adult alcohol dependence and adolescent behavior.
## Alcoholism
Since GABRA 2 subunit mediates anxiolytic activity, long term use or withdrawal of ethanol can cause dependence alterations in the GABA-A receptor.
When alcohol is present in the brain, it affects two types of receptors: GABA-A, inhibitory receptors, and Glutamate, excitatory receptors. In GABA receptors, alcohol substrates binds allosterically, which allows the GABA receptors to increase their inhibitory activity. Besides giving GABA receptors an extra inhibitory punch, alcohol substrates bind to glutamate receptors, which blocks its excitatory activity. Alcohol effects on both of these metabolic pathways obstructs the brain from making memories, making well thought out decisions, and controlling impulses after a long term use.
Collaborative Study on Genetics of Alcoholism (COGA) identified alcohol dependence on chromosome 4p, where SNP genotyping, measurement of genetic variation, found GABRA2's association with alcoholism within European and African ancestries. Most of these findings were strongly associated with early alcohol use and along with drug dependence. Besides these findings, COGA investigators identified GABRA2 associated with impulsiveness and found other phenotypes affected by alcohol such as EEG-β.
## Adolescent behavior
The International Behavioural and Neural Genetics Society reviewed studies that found linkage between β1-subunits in GABA-A receptors and excitability in the reward sensitivity behavior brain region. Linkage between these two suggest that inadequate GABRA2 variants can cause the development of mental disorders, such as addiction. The addictive behaviors can be seen as aggressive and defiant, but most of these behaviors can be caused by both genetic and environmental factors.
GABRA2 genes have been linked to various behavioral traits, such as an absence of impulse control. At least 11 single nucleotide polymorphisms, or SNPs, within the GARBRA2 gene have been correlated to impulsivity and four of which were also found in alcoholism. There was an elevated neuronal activation in the insula and the Nucleus accumbens. In animals, such as rats, a relationship was found between elevated alcohol consumption and increased impulsivity to those exposed to stress at an early stage in life. This impulsivity can be reversed with pharmacological handling of GABA-A receptors containing GABRA2 in certain neurological areas. | GABRA2
Gamma-aminobutyric acid receptor subunit alpha-2 is a protein in humans that is encoded by the GABRA2 gene.[1]
GABRA2 is an alpha subunit that is part of GABA-A receptors, which are ligand-gated chloride channels and are activated by the major inhibitory neurotransmitter in the mammalian brain, GABA. Chloride conductance of these channels can be modulated by agents, such as benzodiazepines (psychoactive drugs) that bind to the GABA-A receptor.
GABA-A receptors are composed of two alpha, two beta, and one gamma subunits. They have at least 16 distinct subunits identified, including GABRA2.[2] This receptor is found mainly in specific regions of the brain, such as the hippocampus.[3]
Subunit isoforms are seen around in various locations in the brain throughout growth. The combination of subunits has a large effect on the pharmacological and biophysical characteristics.[4] GABRA2 has been found to mediate anxiolytic activity, which plays a key role in emotional and behavioral control. Most of GABRA2 modifications have been found to be linked to alcoholism and adolescent behavior.
# Structure
GABRA2 is one of the 16 distinct alpha subunits found for the GABA receptor. GABA-A has a pentametric form, with two alpha, two beta, and one gamma subunit.[3] The various subunit isoforms seen in the GABA-A receptor structure has an effect on its function. GABRA2 is most often seen as part of the most common expression α2β3γ2, which is seen in 13% of all GABA-A receptors.[4] The subunit, GABRA2, is found primarily in hippocampus and/or the forebrain. It is more confined to areas of the brain in comparison to other alpha subunits seen in GABA-A receptors. It is present in 35% of all GABA-A receptors being the fourth most abundant subunit next to GABRA1 and various beta subunits. Like all subunits, it is made from structurally distinct proteins. The presence of this subunit causes an easier binding of benzodiazepine which is a category of psychoactive drugs.[3]
# Function
GABRA2 mediates neural activity necessary for information processing in inter-neurons.[3] GABRA2 participates in transporting Cl− ions into the membrane, since it forms part of the GABA-A receptor. The influx of Cl− causes the hyper-polarization of the membrane, leading to inhibitory actions.
GABRA2 increases the risk of anxiety making it a target for treating behavioral disorders.[5] Some examples of behavioral disorders include anxiety, alcohol dependence, and drug use. GABRA2 is a binding site for benzodiazepines. Benzodiazepines are psychoactive drugs known to reduce anxiety. Benzodiazepines bind to GABRA2 causing chloride channels to open, leading to the hyper-polarization of the membrane.[6] Other anxiolytic drugs like Diazepam target this alpha subunit in GABA-A to induce inhibitory effects.[3]
GABRA2 is associated with reward behavior when it activates the insula.[5] The insula is part of the cerebral cortex responsible for emotions. GABRA2 role in reward behavior explains the higher risk of alcohol dependence and drug use behavior.
# Clinical Significance
Since GABRA 2 mediates anxiolytic activity, it is a key receptor for emotional control. Several developmental stages of GABRA2 have shown effects on behavior such as adult alcohol dependence and adolescent behavior.
## Alcoholism
Since GABRA 2 subunit mediates anxiolytic activity, long term use or withdrawal of ethanol can cause dependence alterations in the GABA-A receptor.[3]
When alcohol is present in the brain, it affects two types of receptors: GABA-A, inhibitory receptors, and Glutamate, excitatory receptors. In GABA receptors, alcohol substrates binds allosterically, which allows the GABA receptors to increase their inhibitory activity. Besides giving GABA receptors an extra inhibitory punch, alcohol substrates bind to glutamate receptors, which blocks its excitatory activity. Alcohol effects on both of these metabolic pathways obstructs the brain from making memories, making well thought out decisions, and controlling impulses after a long term use.[7]
Collaborative Study on Genetics of Alcoholism (COGA) identified alcohol dependence on chromosome 4p, where SNP genotyping, measurement of genetic variation, found GABRA2's association with alcoholism within European and African ancestries. Most of these findings were strongly associated with early alcohol use and along with drug dependence. Besides these findings, COGA investigators identified GABRA2 associated with impulsiveness and found other phenotypes affected by alcohol such as EEG-β.[8]
## Adolescent behavior
The International Behavioural and Neural Genetics Society reviewed studies that found linkage between β1-subunits in GABA-A receptors and excitability in the reward sensitivity behavior brain region. Linkage between these two suggest that inadequate GABRA2 variants can cause the development of mental disorders, such as addiction. The addictive behaviors can be seen as aggressive and defiant, but most of these behaviors can be caused by both genetic and environmental factors.[9]
GABRA2 genes have been linked to various behavioral traits, such as an absence of impulse control. At least 11 single nucleotide polymorphisms, or SNPs, within the GARBRA2 gene have been correlated to impulsivity and four of which were also found in alcoholism. There was an elevated neuronal activation in the insula and the Nucleus accumbens.[9] In animals, such as rats, a relationship was found between elevated alcohol consumption and increased impulsivity to those exposed to stress at an early stage in life. This impulsivity can be reversed with pharmacological handling of GABA-A receptors containing GABRA2 in certain neurological areas.[9] | https://www.wikidoc.org/index.php/GABRA2 | |
a70adb5a90aec31936e4cd768de060bba9473bb6 | wikidoc | GABRA3 | GABRA3
Gamma-aminobutyric acid receptor subunit alpha-3 is a protein that in humans is encoded by the GABRA3 gene.
# Function
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABA-A receptors have been identified. GABA receptors are composed of 5 subunits with an extracellular ligand binding domains and ion channel domains that are integral to the membrane.Ligand binding to these receptors activates the channel.
# Subunit selective ligands
Recent research has produced several ligands that are selective for GABAA receptors containing the α3 subunit. Subtype-selective agonists for α3 produce anxiolytic effects without sedative, amnesia, ataxia.
selective a3 agonists also show lack of dependence, and could make them superior to currently marketed drugs.
## Agonists
- Adipiplon
- PWZ-029 (partial agonist at α3, partial inverse agonist at α5)
- TP003 (Selective full agonist at α3)
## Inverse agonists
- α3IA
# RNA editing
The GABRA3 transcript undergoes pre-mRNA editing by the ADAR family of enzymes. A-to-I editing changes an isoleucine codon to code for a methionine residue. This editing is thought to be important for brain development, as the level of editing is low at birth and becomes almost 100% in an adult brain.
The editing occurs in an RNA stem-loop found in exon 9. The structured loci was identified using a specialised bioinformatics screen of the human genome. The proposed function of the edit is to alter chloride permeability of the GABA receptor.
At the time of discovery, Kv1.1 mRNA was the only previously known mammalian coding site containing both the edit sequence and the editing complementary sequence.
## Type
A to I RNA editing is catalyzed by a family of adenosine deaminases acting on RNA (ADARs) that specifically recognize adenosines within double-stranded regions of pre-mRNAs and deaminate them to inosine. Inosines are recognised as guanosine by the cells translational machinery. There are three members of the ADAR family ADARs 1-3, with ADAR1 and ADAR2 being the only enzymatically active members. ADAR3 is thought to have a regulatory role in the brain. ADAR1 and ADAR 2 are widely expressed in tissues, while ADAR3 is restricted to the brain. The double-stranded regions of RNA are formed by base-pairing between residues in the close to region of the editing site, with residues usually in a neighboring intron but can be an exonic sequence. The region that base pairs with the editing region is known as an Editing Complementary Sequence (ECS).
## Location
The editing site was previously believed to be a single nucleotide polymorphism. The editing site is found at amino acid 5 of transmembrane domain 3 of exon 9. The predicted double-stranded RNA structure is interrupted by three bulges and a mismatch at the editing site. The double-stranded region is 22 base pairs in length. As with editing of the KCNA1 gene product, the editing region and the editing complementary sequence are both found in exonic regions. In the pre=mRNA of GABRA3, both are found within exon 9. The other subunits of the receptor are thought not to be edited, as their predicted secondary structure is less likely to be edited. Also, alpha subunits 1 and 6 have a uridine instead of an adenosine at the site corresponding to the editing site in alpha subunit 3. Point mutation experiments determined that a Cytidine 15 nucleotides from the editing site is the base opposite the edited base. Using a GABRA3 mini-gene that encodes for exon 9 cotransfected to HEK293 cells with either ADAR1 or -2 or none, it was determined that both active ADARs can efficiently edited the site in exon 9.
## Regulation
The mRNA expression of the alpha 3 subunit is developmentally regulated. It is the dominant subunit in the forebrain tissue at birth, gradually decreasing in prominence as alpha subunit 1 takes over. Also experiments with mice have demonstrated that editing of pre-mRNA alpha 3 subunit increases from 50% at birth to nearly 100% in adult. Editing levels are lower in the hippocampus
## Conservation
At the location corresponding to the I/M site of GABRA3 in frog and pufferfish there is a genomically encoded methionine. In all other species, there is an isoleucine at the position.
## Consequences
### Structure
Editing results in a codon change from (AUA)I to (AUG)M at the editing site. This results in translation of a methionine instead of an isoleucine at the I/M site. The amino acid change occurs in the transmembrane domain 3. The 4 transmembrane domains of each of the 5 subunits that make up the receptor interact to form the receptor channel. It is likely that the change of amino acids disturbs the structure, effecting gating and inactivation of the channel. This is because methionine has a larger side chain.
### Function
While the effect of editing on protein function is unknown, the developmental increase in editing does correspond to changes in function of the GAGAA receptor. GABA binding leads to chloride channel activation, resulting in rapid increase in concentration of the ion. Initially, the receptor is an excitatory receptor, mediating depolarisation (efflux of Cl− ions) in immature neurons before changing to an inhibitory receptor, mediating hyperpolarisation(influx of Cl− ions) later on. GABAA converts to an inhibitory receptor from an excitatory receptor by the upregulation of KCC2 cotransporter. This decreases the concentration of Cl− ion within cells. Therefore, the GAGAA subunits are involved in determining the nature of the receptor in response to GABA ligand. These changes suggest that editing of the subunit is important in the developing brain by regulating the Cl− permeability of the channel during development. The unedited receptor is activated faster and deactivates slower than the edited receptor. | GABRA3
Gamma-aminobutyric acid receptor subunit alpha-3 is a protein that in humans is encoded by the GABRA3 gene.[1]
# Function
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABA-A receptors have been identified.[1] GABA receptors are composed of 5 subunits with an extracellular ligand binding domains and ion channel domains that are integral to the membrane.Ligand binding to these receptors activates the channel.[2]
# Subunit selective ligands
Recent research has produced several ligands that are selective for GABAA receptors containing the α3 subunit. Subtype-selective agonists for α3 produce anxiolytic effects without sedative, amnesia, ataxia. [3]
selective a3 agonists also show lack of dependence, [4] and could make them superior to currently marketed drugs.
## Agonists
- Adipiplon
- PWZ-029 (partial agonist at α3, partial inverse agonist at α5)
- TP003 (Selective full agonist at α3)
## Inverse agonists
- α3IA
# RNA editing
The GABRA3 transcript undergoes pre-mRNA editing by the ADAR family of enzymes.[5] A-to-I editing changes an isoleucine codon to code for a methionine residue. This editing is thought to be important for brain development, as the level of editing is low at birth and becomes almost 100% in an adult brain.[5]
The editing occurs in an RNA stem-loop found in exon 9.[5] The structured loci was identified using a specialised bioinformatics screen[6] of the human genome. The proposed function of the edit is to alter chloride permeability of the GABA receptor.[5]
At the time of discovery, Kv1.1 mRNA was the only previously known mammalian coding site containing both the edit sequence and the editing complementary sequence.[7]
## Type
A to I RNA editing is catalyzed by a family of adenosine deaminases acting on RNA (ADARs) that specifically recognize adenosines within double-stranded regions of pre-mRNAs and deaminate them to inosine. Inosines are recognised as guanosine by the cells translational machinery. There are three members of the ADAR family ADARs 1-3, with ADAR1 and ADAR2 being the only enzymatically active members. ADAR3 is thought to have a regulatory role in the brain. ADAR1 and ADAR 2 are widely expressed in tissues, while ADAR3 is restricted to the brain. The double-stranded regions of RNA are formed by base-pairing between residues in the close to region of the editing site, with residues usually in a neighboring intron but can be an exonic sequence. The region that base pairs with the editing region is known as an Editing Complementary Sequence (ECS).
## Location
The editing site was previously believed to be a single nucleotide polymorphism.[8] The editing site is found at amino acid 5 of transmembrane domain 3 of exon 9. The predicted double-stranded RNA structure is interrupted by three bulges and a mismatch at the editing site. The double-stranded region is 22 base pairs in length. As with editing of the KCNA1 gene product,[7] the editing region and the editing complementary sequence are both found in exonic regions. In the pre=mRNA of GABRA3, both are found within exon 9.[5] The other subunits of the receptor are thought not to be edited, as their predicted secondary structure is less likely to be edited. Also, alpha subunits 1 and 6 have a uridine instead of an adenosine at the site corresponding to the editing site in alpha subunit 3.[5] Point mutation experiments determined that a Cytidine 15 nucleotides from the editing site is the base opposite the edited base.[5] Using a GABRA3 mini-gene that encodes for exon 9 cotransfected to HEK293 cells with either ADAR1 or -2 or none, it was determined that both active ADARs can efficiently edited the site in exon 9.[5]
## Regulation
The mRNA expression of the alpha 3 subunit is developmentally regulated. It is the dominant subunit in the forebrain tissue at birth, gradually decreasing in prominence as alpha subunit 1 takes over. Also experiments with mice have demonstrated that editing of pre-mRNA alpha 3 subunit increases from 50% at birth to nearly 100% in adult.[5] Editing levels are lower in the hippocampus[9]
## Conservation
At the location corresponding to the I/M site of GABRA3 in frog and pufferfish there is a genomically encoded methionine. In all other species, there is an isoleucine at the position.[10]
## Consequences
### Structure
Editing results in a codon change from (AUA)I to (AUG)M at the editing site. This results in translation of a methionine instead of an isoleucine at the I/M site. The amino acid change occurs in the transmembrane domain 3. The 4 transmembrane domains of each of the 5 subunits that make up the receptor interact to form the receptor channel. It is likely that the change of amino acids disturbs the structure, effecting gating and inactivation of the channel.[11] This is because methionine has a larger side chain.[5]
### Function
While the effect of editing on protein function is unknown, the developmental increase in editing does correspond to changes in function of the GAGAA receptor. GABA binding leads to chloride channel activation, resulting in rapid increase in concentration of the ion. Initially, the receptor is an excitatory receptor, mediating depolarisation (efflux of Cl− ions) in immature neurons before changing to an inhibitory receptor, mediating hyperpolarisation(influx of Cl− ions) later on.[12] GABAA converts to an inhibitory receptor from an excitatory receptor by the upregulation of KCC2 cotransporter. This decreases the concentration of Cl− ion within cells. Therefore, the GAGAA subunits are involved in determining the nature of the receptor in response to GABA ligand.[13] These changes suggest that editing of the subunit is important in the developing brain by regulating the Cl− permeability of the channel during development. The unedited receptor is activated faster and deactivates slower than the edited receptor.[5] | https://www.wikidoc.org/index.php/GABRA3 | |
f1b1451df4367c65e6866c149940649ae010f49e | wikidoc | GABRA5 | GABRA5
Gamma-aminobutyric acid (GABA) A receptor, alpha 5, also known as GABRA5, is a protein which in humans is encoded by the GABRA5 gene.
# Function
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABAA receptors have been identified. Transcript variants utilizing three different alternative non-coding first exons have been described.
# Subunit selective ligands
Recent research has produced several ligands which are moderately selective for GABAA receptors containing the α5 subunit. These have proved to be useful in investigating some of the side effects of benzodiazepine and nonbenzodiazepine drugs, particularly the effects on learning and memory such as anterograde amnesia. Inverse agonists at this subunit have nootropic effects and may be useful for the treatment of cognitive disorders such as Alzheimer's disease.
## Agonists
- QH-ii-066
- SH-053-R-CH3-2′F
## Inverse agonists
- α5IA
- Basmisanil (RG-1662, RO5186582): derivative of Ro4938581, negative allosteric modulator at GABAA α5, in human trials for treating cognitive deficit in Down syndrome.
- L-655,708
- MRK-016
- PWZ-029: moderate inverse agonist
- Pyridazines
- Ro4938581
- TB-21007 | GABRA5
Gamma-aminobutyric acid (GABA) A receptor, alpha 5, also known as GABRA5, is a protein which in humans is encoded by the GABRA5 gene.[1][2]
# Function
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABAA receptors have been identified. Transcript variants utilizing three different alternative non-coding first exons have been described.[1]
# Subunit selective ligands
Recent research has produced several ligands which are moderately selective for GABAA receptors containing the α5 subunit. These have proved to be useful in investigating some of the side effects of benzodiazepine and nonbenzodiazepine drugs, particularly the effects on learning and memory such as anterograde amnesia. Inverse agonists at this subunit have nootropic effects and may be useful for the treatment of cognitive disorders such as Alzheimer's disease.
## Agonists
- QH-ii-066
- SH-053-R-CH3-2′F
## Inverse agonists
- α5IA
- Basmisanil (RG-1662, RO5186582): derivative of Ro4938581, negative allosteric modulator at GABAA α5, in human trials for treating cognitive deficit in Down syndrome.[3]
- L-655,708
- MRK-016
- PWZ-029: moderate inverse agonist[4]
- Pyridazines[5]
- Ro4938581[6]
- TB-21007[7][8] | https://www.wikidoc.org/index.php/GABRA5 | |
90860ef277e076936bd7bb2eb9dc3442c433883c | wikidoc | GABRA6 | GABRA6
Gamma-aminobutyric acid receptor subunit alpha-6 is a protein that in humans is encoded by the GABRA6 gene.
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified.
One study has found a genetic variant in the gene to be associated with the personality trait neuroticism. | GABRA6
Gamma-aminobutyric acid receptor subunit alpha-6 is a protein that in humans is encoded by the GABRA6 gene.[1][2]
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified.[2]
One study has found a genetic variant in the gene to be associated with the personality trait neuroticism.[3] | https://www.wikidoc.org/index.php/GABRA6 | |
804d20c408962c5478079ccae1f977e74310d5b3 | wikidoc | GABRB1 | GABRB1
Gamma-aminobutyric acid receptor subunit beta-1 is a protein that in humans is encoded by the GABRB1 gene.
# Function
The gamma-aminobutyric acid A receptor (GABAA receptor) is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes GABA A receptor, beta 1 subunit. It is mapped to chromosome 4p12 in a cluster of genes encoding alpha 4, alpha 2 and gamma 1 subunits of the GABAA receptor. Alteration of this gene is implicated in the pathogenetics of schizophrenia.
# Clinical significance
Mice bearing mutant copies of this gene have been shown to be vulnerable to binge drinking of alcohol. | GABRB1
Gamma-aminobutyric acid receptor subunit beta-1 is a protein that in humans is encoded by the GABRB1 gene.[1]
# Function
The gamma-aminobutyric acid A receptor (GABAA receptor) is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes GABA A receptor, beta 1 subunit. It is mapped to chromosome 4p12 in a cluster of genes encoding alpha 4, alpha 2 and gamma 1 subunits of the GABAA receptor. Alteration of this gene is implicated in the pathogenetics of schizophrenia.[1]
# Clinical significance
Mice bearing mutant copies of this gene have been shown to be vulnerable to binge drinking of alcohol.[2] | https://www.wikidoc.org/index.php/GABRB1 | |
c668767a1bc986a3751aef9ff063679eaa53b920 | wikidoc | GABRB2 | GABRB2
Gamma-aminobutyric acid receptor subunit beta-2 is a protein that in humans is encoded by the GABRB2 gene.
# Function
The gamma-aminobutyric acid (GABA) A receptor is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes GABA A receptor, beta 2 subunit. It is mapped to chromosome 5q34 in a cluster of genes encoding alpha 1 and gamma 2 subunits of the GABA A receptor. Alternative splicing of this gene generates 2 transcript variants, differing by a 114 bp insertion.
# Clinical significance
Missense mutations of GABRB2 have been identified in patients with infantile onset epilepsy and intellectual disability.
# Interactions
GABRB2 has been shown to interact with TRAK2. | GABRB2
Gamma-aminobutyric acid receptor subunit beta-2 is a protein that in humans is encoded by the GABRB2 gene.[1][2]
# Function
The gamma-aminobutyric acid (GABA) A receptor is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes GABA A receptor, beta 2 subunit. It is mapped to chromosome 5q34 in a cluster of genes encoding alpha 1 and gamma 2 subunits of the GABA A receptor. Alternative splicing of this gene generates 2 transcript variants, differing by a 114 bp insertion.[2]
# Clinical significance
Missense mutations of GABRB2 have been identified in patients with infantile onset epilepsy and intellectual disability.[3][4]
# Interactions
GABRB2 has been shown to interact with TRAK2.[5] | https://www.wikidoc.org/index.php/GABRB2 | |
6e39e9097273ffbeae35c9e20918f222aef6372f | wikidoc | GABRB3 | GABRB3
Gamma-aminobutyric acid receptor subunit beta-3 is a protein that in humans is encoded by the GABRB3 gene. It is located within the 15q12 region in the human genome and spans 250kb. This gene includes 10 exons within its coding region. Due to alternative splicing, the gene codes for many protein isoforms, all being subunits in the GABAA receptor, a ligand-gated ion channel. The beta-3 subunit is expressed at different levels within the cerebral cortex, hippocampus, cerebellum, thalamus, olivary body and piriform cortex of the brain at different points of development and maturity. GABRB3 deficiencies are implicated in many human neurodevelopmental disorders and syndromes such as Angelman syndrome, Prader-Willi syndrome, nonsyndromic orofacial clefts, epilepsy and autism. The effects of methaqualone and etomidate are mediated through GABBR3 positive allosteric modulation.
# Gene
The GABRB3 gene is located on the long arm of chromosome 15, within the q12 region in the human genome. It is located in a gene cluster, with two other genes, GABRG3 and GABRA5. GABRB3 was the first gene to be mapped to this particular region. It spans approximately 250kb and includes 10 exons within its coding region, as well as two additional alternative first exons that encode for signaling peptides. Alternatively spliced transcript variants encoding isoforms with distinct signal peptides have been described. This gene is located within an imprinting region that spans the 15q11-13 region. It's sequence is considerably longer than the two other genes found within its gene cluster due to a large 150kb intron it carries. A pattern is observed in GABRB3 gene replication, in humans the maternal allele is replicated later than the paternal allele. The reasoning and implications of this pattern are unknown.
When comparing the human beta-3 subunit's genetic sequence with other vertebrate beta-3 subunit sequences, there is a high level of genetic conservation. In mice the Gabrb3 gene is located on chromosome 7 of its genome in a similar gene cluster style with some of the other subunits of the GABAA receptor.
# Function
GABRB3 encodes a member of the ligand-gated ion channel family. The encoded protein is one of at least 13 distinct subunits of a multisubunit chloride channel that serves as the receptor for gamma-aminobutyric acid, the major inhibitory neurotransmitter of the nervous system. The two other genes in the gene cluster both encode for related subunits of the family. During development, when the GABRB3 subunit functions optimally, its role in the GABAA receptor allows for proliferation, migration, and differentiation of precursor cells that lead to the proper development of the brain. GABAA receptor function is inhibited by zinc ions. The ions bind allosterically to the receptor, a mechanism that is critically dependent on the receptor subunit composition.
De novo heterozygous missense mutations within a highly conserved region of the GABRB3 gene can decrease the peak current amplitudes of neurons or alter the kinetic properties of the channel. This results in the loss of the inhibitory properties of the receptor.
The beta-3 subunit has very similar function to the human version of the subunit.
# Structure
The crystal structure of a human β3 homopentamer was published in 2014. The study of the crystal structure of the human β3 homopentamer revealed unique qualities that are only observed in eukaryotic cysteine-loop receptors. The characterization of the GABAA receptor and subunits helps with the mechanistic determination of mutations within the subunits and what direct effect the mutations may have on the protein and it's interactions.
# Expression
The expression of GABRB3 is not constant among all cells or at all stages of development. The distribution of expression of the GABAA receptor subunits (GABRB3 included) during development indicates that GABA may function as a neurotrophic factor, impacting neural differentiation, growth, and circuit organization. The expression of the beta-3 subunit reaches peak at different times in different locations of the brain, during development. The highest expression of Gabrb3 in mice, within the cerebral cortex and hippocampus are reached prenatally, while they are reached postnatally in the cerebellar cortex. After the highest peak of expression, Gabrb3 expression is down-regulated substantially in the thalamus and inferior olivary body of the mouse. By adulthood, the level of expression in the cerebral cortex and hippocampus drops below developmental expression levels, but the expression in the cerebellum does not change postnatally. The highest levels of Gabrb3 expression in the mature mouse brain occur in the Purkinje and granule cells of the cerebellum, the hippocampus, and the piriform cortex.
In humans, the beta-3 subunit, as well as the subunits of its two neighbouring genes (GABRG3 and GABRA5), are bi-allelically expressed within the cerebral cortex, indicating that the gene is not subjected to imprinting within those cells.
## Imprinting Patterns
Due to the location of GABRB3 in the 15q11-13 imprinting region found in humans, this gene is subject to imprinting depending on the location and the cells developmental state. Imprinting is not present in the mouse brain, having an equal expression from maternal and paternal alleles.
# Regulation
Phosphorylation of the GABAA by cAMP-dependent protein kinase (PKA) has a regulatory effect dependent on the beta subunit involved. The mechanism by which the kinase is targeted towards the bata-3 subunit is unknown. AKAP79/150 binds directly to the GABRB3 subunit, which is critical for its own phosphorylation, mediated by PKA.
Gabrb3 shows significantly reduced expression postnatally, when mice are deficient in MECP2. When the MECP2 gene is knocked out, the expression of Gabrb3 is reduced, suggesting a relationship of positive regulation between the two genes.
# Clinical significance
Mutations in this gene may be associated with the pathogenesis of Angelman syndrome, nonsyndromic orofacial clefts, epilepsy and autism. The GABRB3 gene has been associated with savant skills accompanying such disorders.
In mice, the knockout mutation of Gabrb3 causes severe neonatal mortality with the cleft palate phenotype present, the survivors experiencing hyperactivity, lack of coordination and suffering with epileptic seizures. These mice also exhibit changes to the vestibular system within the ear, resulting in poor swimming skills, difficulty in walking on grid floors, and are found to run in circles erratically.
## Angelman syndrome
Deletion of the GABRB3 gene results in Angelman syndrome in humans, depending on the parental origin of the deletion. Deletion of the paternal allele of GABRB3 has no known implications with this syndrome, while deletion of the maternal GABRB3 allele results in development of the syndrome.
## Nonsyndromic Orofacial Clefting
There is a strong association between GABRB3 expression levels and proper palate development. A disturbance in GABRB3 expression can be lined to the malformation of nonsyndromic cleft lip with or without cleft palate. Cleft lip and palate have also been observed in children who have inverted duplications encompassing the GABRB3 locus. Knockout of the beta-3 subunit in mice results in clefting of the secondary palate. Normal facial characteristics can be restored through the insertion of a Gabrb3 transgene into the mouse genome, making the Gabrb3 gene primarily responsible for cleft palate formation.
## Autism Spectrum Disorder
Duplications of the Prader-Willi/Angelman syndrome region, also known as the imprinting region (15q11-13) that encompasses the GABRB3 gene are present in some patients diagnosed with Autism. These patients exhibit classic symptoms that are associated with the disorder. Duplications of the 15q11-13 region displayed in autistic patients are almost always of maternal origin (not paternal) and account for 1-2% of diagnosed autism disorder cases. This gene is also a candidate for autism because of the physiological response that benzodiazepine has on the GABA-A receptor, when used to treat seizures and anxiety disorders.
The Gabrb3 gene deficient mouse has been proposed as a model of autism spectrum disorder. These mice exhibit similar phenotypic symptoms such as non-selective attention, deficits in a variety of exploratory parameters, sociability, social novelty, nesting and lower rearing frequency as can be equated to characteristics found in patients diagnosed with autism spectrum disorder. When studying Gabrb3 deficient mice, significant hypoplasia of the cerebellar vermis was observed.
There is an unknown association between autism and the 155CA-2 locus, located within an intron in GABRB3.
## Epilepsy/Childhood absence epilepsy
Defects in GABA transmission has often been implicated in epilepsy within animal models and human syndromes. Patients that are diagnosed with Angelman syndrome and have a deletion of the GABRB3 gene exhibit absence seizures. Reduced expression of the beta-3 subunit is a potential contributor to childhood absence epilepsy. | GABRB3
Gamma-aminobutyric acid receptor subunit beta-3 is a protein that in humans is encoded by the GABRB3 gene. It is located within the 15q12 region in the human genome and spans 250kb.[1] This gene includes 10 exons within its coding region.[1] Due to alternative splicing, the gene codes for many protein isoforms, all being subunits in the GABAA receptor, a ligand-gated ion channel. The beta-3 subunit is expressed at different levels within the cerebral cortex, hippocampus, cerebellum, thalamus, olivary body and piriform cortex of the brain at different points of development and maturity.[2] GABRB3 deficiencies are implicated in many human neurodevelopmental disorders and syndromes such as Angelman syndrome, Prader-Willi syndrome, nonsyndromic orofacial clefts, epilepsy and autism. The effects of methaqualone[3] and etomidate are mediated through GABBR3 positive allosteric modulation.
# Gene
The GABRB3 gene is located on the long arm of chromosome 15, within the q12 region in the human genome. It is located in a gene cluster, with two other genes, GABRG3 and GABRA5. GABRB3 was the first gene to be mapped to this particular region.[4] It spans approximately 250kb and includes 10 exons within its coding region, as well as two additional alternative first exons that encode for signaling peptides.[1] Alternatively spliced transcript variants encoding isoforms with distinct signal peptides have been described.[5] This gene is located within an imprinting region that spans the 15q11-13 region. It's sequence is considerably longer than the two other genes found within its gene cluster due to a large 150kb intron it carries. A pattern is observed in GABRB3 gene replication, in humans the maternal allele is replicated later than the paternal allele.[6] The reasoning and implications of this pattern are unknown.
When comparing the human beta-3 subunit's genetic sequence with other vertebrate beta-3 subunit sequences, there is a high level of genetic conservation.[4] In mice the Gabrb3 gene is located on chromosome 7 of its genome[7] in a similar gene cluster style with some of the other subunits of the GABAA receptor.[8]
# Function
GABRB3 encodes a member of the ligand-gated ion channel family. The encoded protein is one of at least 13 distinct subunits of a multisubunit chloride channel that serves as the receptor for gamma-aminobutyric acid, the major inhibitory neurotransmitter of the nervous system. The two other genes in the gene cluster both encode for related subunits of the family. During development, when the GABRB3 subunit functions optimally, its role in the GABAA receptor allows for proliferation, migration, and differentiation of precursor cells that lead to the proper development of the brain.[9] GABAA receptor function is inhibited by zinc ions. The ions bind allosterically to the receptor, a mechanism that is critically dependent on the receptor subunit composition.[10]
De novo heterozygous missense mutations within a highly conserved region of the GABRB3 gene can decrease the peak current amplitudes of neurons or alter the kinetic properties of the channel.[11] This results in the loss of the inhibitory properties of the receptor.
The beta-3 subunit has very similar function to the human version of the subunit.[7]
# Structure
The crystal structure of a human β3 homopentamer was published in 2014.[12][13] The study of the crystal structure of the human β3 homopentamer revealed unique qualities that are only observed in eukaryotic cysteine-loop receptors. The characterization of the GABAA receptor and subunits helps with the mechanistic determination of mutations within the subunits and what direct effect the mutations may have on the protein and it's interactions.[12]
# Expression
The expression of GABRB3 is not constant among all cells or at all stages of development. The distribution of expression of the GABAA receptor subunits (GABRB3 included) during development indicates that GABA may function as a neurotrophic factor, impacting neural differentiation, growth, and circuit organization. The expression of the beta-3 subunit reaches peak at different times in different locations of the brain, during development. The highest expression of Gabrb3 in mice, within the cerebral cortex and hippocampus are reached prenatally, while they are reached postnatally in the cerebellar cortex. After the highest peak of expression, Gabrb3 expression is down-regulated substantially in the thalamus and inferior olivary body of the mouse. By adulthood, the level of expression in the cerebral cortex and hippocampus drops below developmental expression levels, but the expression in the cerebellum does not change postnatally. The highest levels of Gabrb3 expression in the mature mouse brain occur in the Purkinje and granule cells of the cerebellum, the hippocampus, and the piriform cortex.[2]
In humans, the beta-3 subunit, as well as the subunits of its two neighbouring genes (GABRG3 and GABRA5), are bi-allelically expressed within the cerebral cortex, indicating that the gene is not subjected to imprinting within those cells.[14]
## Imprinting Patterns
Due to the location of GABRB3 in the 15q11-13 imprinting region found in humans, this gene is subject to imprinting depending on the location and the cells developmental state. Imprinting is not present in the mouse brain, having an equal expression from maternal and paternal alleles.[7]
# Regulation
Phosphorylation of the GABAA by cAMP-dependent protein kinase (PKA) has a regulatory effect dependent on the beta subunit involved. The mechanism by which the kinase is targeted towards the bata-3 subunit is unknown. AKAP79/150 binds directly to the GABRB3 subunit, which is critical for its own phosphorylation, mediated by PKA.[15]
Gabrb3 shows significantly reduced expression postnatally, when mice are deficient in MECP2. When the MECP2 gene is knocked out, the expression of Gabrb3 is reduced, suggesting a relationship of positive regulation between the two genes.[9]
# Clinical significance
Mutations in this gene may be associated with the pathogenesis of Angelman syndrome, nonsyndromic orofacial clefts, epilepsy and autism. The GABRB3 gene has been associated with savant skills accompanying such disorders.[16]
In mice, the knockout mutation of Gabrb3 causes severe neonatal mortality with the cleft palate phenotype present, the survivors experiencing hyperactivity, lack of coordination and suffering with epileptic seizures.[8] These mice also exhibit changes to the vestibular system within the ear, resulting in poor swimming skills, difficulty in walking on grid floors, and are found to run in circles erratically.[9]
## Angelman syndrome
Deletion of the GABRB3 gene results in Angelman syndrome in humans, depending on the parental origin of the deletion.[9] Deletion of the paternal allele of GABRB3 has no known implications with this syndrome, while deletion of the maternal GABRB3 allele results in development of the syndrome.[17]
## Nonsyndromic Orofacial Clefting
There is a strong association between GABRB3 expression levels and proper palate development. A disturbance in GABRB3 expression can be lined to the malformation of nonsyndromic cleft lip with or without cleft palate. Cleft lip and palate have also been observed in children who have inverted duplications encompassing the GABRB3 locus. Knockout of the beta-3 subunit in mice results in clefting of the secondary palate. Normal facial characteristics can be restored through the insertion of a Gabrb3 transgene into the mouse genome, making the Gabrb3 gene primarily responsible for cleft palate formation.[8]
## Autism Spectrum Disorder
Duplications of the Prader-Willi/Angelman syndrome region, also known as the imprinting region (15q11-13) that encompasses the GABRB3 gene are present in some patients diagnosed with Autism.[2] These patients exhibit classic symptoms that are associated with the disorder. Duplications of the 15q11-13 region displayed in autistic patients are almost always of maternal origin (not paternal) and account for 1-2% of diagnosed autism disorder cases.[9] This gene is also a candidate for autism because of the physiological response that benzodiazepine has on the GABA-A receptor, when used to treat seizures and anxiety disorders.[2]
The Gabrb3 gene deficient mouse has been proposed as a model of autism spectrum disorder.[9] These mice exhibit similar phenotypic symptoms such as non-selective attention, deficits in a variety of exploratory parameters, sociability, social novelty, nesting and lower rearing frequency as can be equated to characteristics found in patients diagnosed with autism spectrum disorder. When studying Gabrb3 deficient mice, significant hypoplasia of the cerebellar vermis was observed.[9]
There is an unknown association between autism and the 155CA-2 locus, located within an intron in GABRB3.[18]
## Epilepsy/Childhood absence epilepsy
Defects in GABA transmission has often been implicated in epilepsy within animal models and human syndromes.[19] Patients that are diagnosed with Angelman syndrome and have a deletion of the GABRB3 gene exhibit absence seizures.[20] Reduced expression of the beta-3 subunit is a potential contributor to childhood absence epilepsy.[21] | https://www.wikidoc.org/index.php/GABRB3 | |
ac235e160ae316b57ed3d73ba8ccd758b5047a44 | wikidoc | GABRG2 | GABRG2
Gamma-aminobutyric acid receptor subunit gamma-2 is a protein that in humans is encoded by the GABRG2 gene.
# Function
Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the brain, mediates neuronal inhibition by binding to GABA receptors. The type A GABA receptors are pentameric chloride channels assembled from among many genetic variants of GABA(A) subunits. This gene encodes the gamma 2 subunit of GABA(A) receptor. Mutations in this gene have been associated with epilepsy and febrile seizures. Alternative splicing of this gene results in transcript variants encoding different isoforms.
# Interactions
GABRG2 has been shown to interact with GABARAP and Dopamine receptor D5. | GABRG2
Gamma-aminobutyric acid receptor subunit gamma-2 is a protein that in humans is encoded by the GABRG2 gene.
# Function
Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the brain, mediates neuronal inhibition by binding to GABA receptors. The type A GABA receptors are pentameric chloride channels assembled from among many genetic variants of GABA(A) subunits. This gene encodes the gamma 2 subunit of GABA(A) receptor. Mutations in this gene have been associated with epilepsy and febrile seizures. Alternative splicing of this gene results in transcript variants encoding different isoforms.[1]
# Interactions
GABRG2 has been shown to interact with GABARAP[2][3][4] and Dopamine receptor D5.[5] | https://www.wikidoc.org/index.php/GABRG2 | |
f4ffb70c6d35deefe96fbff8a12d5f09280d471e | wikidoc | GABRG3 | GABRG3
GABAA receptor-γ3, also known as GABRG3, is a protein which in humans is encoded by the GABRG3 gene.
# Function
GABRG3 is a subunit of the GABAA receptor for the neurotransmitter gamma-Aminobutyric acid (GABA).
# Association with alcoholism
Genetic markers near the GABRG3 gene are statistically linked to alcoholism. | GABRG3
GABAA receptor-γ3, also known as GABRG3, is a protein which in humans is encoded by the GABRG3 gene.
# Function
GABRG3 is a subunit of the GABAA receptor for the neurotransmitter gamma-Aminobutyric acid (GABA).[1]
# Association with alcoholism
Genetic markers near the GABRG3 gene are statistically linked to alcoholism.[2] | https://www.wikidoc.org/index.php/GABRG3 | |
b682284a2429b5c50b239c9bd35dfb1db2404bd1 | wikidoc | GAPDHS | GAPDHS
Glyceraldehyde-3-phosphate dehydrogenase, spermatogenic or glyceraldehyde-3-phosphate dehydrogenase, testis-specific is an enzyme that in humans is encoded by the GAPDHS gene.
# Function
This gene encodes a protein belonging to the glyceraldehyde-3-phosphate dehydrogenase family of enzymes that play an important role in carbohydrate metabolism. Like its somatic cell counterpart, this sperm-specific enzyme functions in a nicotinamide adenine dinucleotide-dependent manner to remove hydrogen and add phosphate to glyceraldehyde 3-phosphate to form 1,3-diphosphoglycerate. During spermiogenesis, this enzyme may play an important role in regulating the switch between different energy-producing pathways, and it is required for sperm motility and male fertility.
In melanocytic cells GAPDHS gene expression may be regulated by MITF.
# Interactive pathway map
Click on genes, proteins and metabolites below to link to respective articles.
- ↑ The interactive pathway map can be edited at WikiPathways: "GlycolysisGluconeogenesis_WP534"..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em} | GAPDHS
Glyceraldehyde-3-phosphate dehydrogenase, spermatogenic or glyceraldehyde-3-phosphate dehydrogenase, testis-specific is an enzyme that in humans is encoded by the GAPDHS gene.[1][2]
# Function
This gene encodes a protein belonging to the glyceraldehyde-3-phosphate dehydrogenase family of enzymes that play an important role in carbohydrate metabolism. Like its somatic cell counterpart, this sperm-specific enzyme functions in a nicotinamide adenine dinucleotide-dependent manner to remove hydrogen and add phosphate to glyceraldehyde 3-phosphate to form 1,3-diphosphoglycerate. During spermiogenesis, this enzyme may play an important role in regulating the switch between different energy-producing pathways, and it is required for sperm motility and male fertility.[2]
In melanocytic cells GAPDHS gene expression may be regulated by MITF.[3]
# Interactive pathway map
Click on genes, proteins and metabolites below to link to respective articles. [§ 1]
- ↑ The interactive pathway map can be edited at WikiPathways: "GlycolysisGluconeogenesis_WP534"..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em} | https://www.wikidoc.org/index.php/GAPDHS | |
886982422a0b221941d84f24c0d844a39fbfc252 | wikidoc | GAPVD1 | GAPVD1
GTPase activating protein and VPS9 domains 1, also known as GAPVD1, Gapex-5 and RME-6 is a protein which in humans is encoded by the GAPVD1 gene.
# Function
GAPVD1 is Rab GTPase guanine nucleotide exchange factor essential for activation of RAB5A during engulfment of apoptotic cells. GAPVD1 is also involved in the degradation of the epidermal growth factor receptor.
Gapex-5 mediated activation of Rab5 has been implicated in the insulin stimulated formation of plasma membrane phosphatidylinositol-3-phosphate.
# Structure
Based on sequence homology, mammalian Gapex-5 has been shown to have an amino-terminal Ras GAP domain, a central polyproline (SH3 binding) region and a carboxy-terminal Rab GEF domain. The RabGEF domain has been suggested to activate Rab5 and Rab31. | GAPVD1
GTPase activating protein and VPS9 domains 1, also known as GAPVD1, Gapex-5 and RME-6 is a protein which in humans is encoded by the GAPVD1 gene.[1][2]
# Function
GAPVD1 is Rab GTPase guanine nucleotide exchange factor essential for activation of RAB5A during engulfment of apoptotic cells.[3] GAPVD1 is also involved in the degradation of the epidermal growth factor receptor.[4]
Gapex-5 mediated activation of Rab5 has been implicated in the insulin stimulated formation of plasma membrane phosphatidylinositol-3-phosphate.[5]
# Structure
Based on sequence homology, mammalian Gapex-5 has been shown to have an amino-terminal Ras GAP domain, a central polyproline (SH3 binding) region and a carboxy-terminal Rab GEF domain. The RabGEF domain has been suggested to activate Rab5[6] and Rab31.[7] | https://www.wikidoc.org/index.php/GAPVD1 | |
41a8451f133f1aaf954a8ce5a892283c6b1d95de | wikidoc | GLIPR1 | GLIPR1
Glioma pathogenesis-related protein 1 is a protein that in humans is encoded by the GLIPR1 gene.
# Function
This gene encodes a protein with similarity to both the pathogenesis-related protein (PR) superfamily and the cysteine-rich secretory protein (CRISP) family.
# Discovery
The previous finding of RTVP1 (GLIPR1) as a p53 target gene with tumor suppressor functions prompted the researches to initiate a genome-wide sequence homology search for RTVP1/GLIPR1-like (GLIPR1L) genes. p53, the tumor suppressor gene is the most commonly mutated gene in human cancer. Mutation in p53 gene can lead to cellular malfunctions such as malignant growth and metsastatis. Human GLIPR1, was initially identified in human glioblastoma and was called as GLIPR1 (glioma pathogenesis-related protein 1) or RTVP1 (related to testes-specific, vespid, and pathogenesis protein 1). Furthermore, it was identified as a marker of myelomocytic differentiation in macrophage. RTVP-1 cluster proteins share significant sequence homology with the members of (PR ) superfamily and CRISP Family proteins.
# Structure
Protein structure:
GLIPR1 is in two isomeric form, identifier: P48060-1 and P48060-2, which encodes 266(30,366 da) and 236( 26, 919 Da ) amino acid. The GLIPR1 proteins contains following domains:
- SCP: SCP-like extracellular protein domain
-CAP: Cysteine-rich secretory protein family
These predicted transmembrane domains a makes them unique to mammalian CAP proteins and are not presented in any othert GLIPR1 isoforms. CAP domain is 15 KDa structurally conserved cystine rich domain as was historically referred to as SCP, NCBI cd00168 pr Pfam00188.
# Gene location
GLIPR1L and Glipr1l genes are located very near RTVP1 within the range of 170 kb, in human it is in chromosome 12q21 and in chromosome 10D1 in mouse (Figs. 1A and 1B). In human GLIPR1 gene is located on the long (q) arm of chromosome 12 from base pair 71500001-75700000 (Build GRCh37/hg19)(map)
# Gene expression
GlIPR1 is highly tissue specific with high mRNA, with the expression of GLIPR1L1 being with very high mRNA levels in testes but few traces in bladder followed by undetectable expression in prostate, kidney, lung, and bone marrow. The expression GLIPR1L2 was similar to GLIPR1L1.
# Clinical significance
Study showed human GLIPR1 promoter to be highly methylated in prostate cancer tissues compared to the normal prostate tissue correlating with the decreased level of GLIPR1 expression. Hence, GLIPR1 has been proposed to act as a tumor suppressor that undergoes epigenetic inactivation in prostate cancer.
This unique property of GLIPR1 might be effective for the control of malignancies. Preclinical studies has the significant suppression of tumor growth when AdGLIPR1 was directly injected into prostate cancer using an immunocompetent orthotopic mouse model.
# Homology with plant defense mechanism
GLIPR1 exhibits 35% amino acid sequence identity with the tomato pathogenesis-related (PR) protein P14a, which has importance in plant defense mechanism. Comparison of these two protein lead to the identification of a common partially solvent-exposed spatial cluster of four amino acid residues, His-69, Glu-88, Glu-110, and His-127 in the GliPR numeration which indicates a common putative active site for GliPR and PR-1 proteins making a functional link between the human immune system and a plant defense system.
# Cancer types/SNP positions
The graphical representation of number of positions affected by cancer type vs cancer type and number of cancer types vs postiiton in amino acid sequence is provided in the link. | GLIPR1
Glioma pathogenesis-related protein 1 is a protein that in humans is encoded by the GLIPR1 gene.[1][2][3]
# Function
This gene encodes a protein with similarity to both the pathogenesis-related protein (PR) superfamily and the cysteine-rich secretory protein (CRISP) family.[3]
# Discovery
The previous finding of RTVP1 (GLIPR1) as a p53 target gene with tumor suppressor functions prompted the researches to initiate a genome-wide sequence homology search for RTVP1/GLIPR1-like (GLIPR1L) genes.[4] p53, the tumor suppressor gene is the most commonly mutated gene in human cancer.[4] Mutation in p53 gene can lead to cellular malfunctions such as malignant growth and metsastatis.[5][6][7] Human GLIPR1, was initially identified in human glioblastoma and was called as GLIPR1 (glioma pathogenesis-related protein 1)[8] or RTVP1 (related to testes-specific, vespid, and pathogenesis protein 1).[9] Furthermore, it was identified as a marker of myelomocytic differentiation in macrophage.[10] RTVP-1 cluster proteins share significant sequence homology with the members of (PR ) superfamily and CRISP Family proteins.[4]
# Structure
Protein structure:
GLIPR1 is in two isomeric form, identifier: P48060-1 and P48060-2, which encodes 266(30,366 da) and 236( 26, 919 Da ) amino acid.[11] [3] The GLIPR1 proteins contains following domains:
• SCP: SCP-like extracellular protein domain
•CAP: Cysteine-rich secretory protein family
These predicted transmembrane domains a makes them unique to mammalian CAP proteins and are not presented in any othert GLIPR1 isoforms.[12] CAP domain is 15 KDa structurally conserved cystine rich domain as was historically referred to as SCP, NCBI cd00168 pr Pfam00188.[4][11]
# Gene location
GLIPR1L and Glipr1l genes are located very near RTVP1 within the range of 170 kb, in human it is in chromosome 12q21 and in chromosome 10D1 in mouse (Figs. 1A and 1B).[4] In human GLIPR1 gene is located on the long (q) arm of chromosome 12 from base pair 71500001-75700000 (Build GRCh37/hg19)(map)[13]
# Gene expression
GlIPR1 is highly tissue specific with high mRNA, with the expression of GLIPR1L1 being with very high mRNA levels in testes but few traces in bladder followed by undetectable expression in prostate, kidney, lung, and bone marrow.[4] The expression GLIPR1L2 was similar to GLIPR1L1.[4]
# Clinical significance
Study showed human GLIPR1 promoter to be highly methylated in prostate cancer tissues compared to the normal prostate tissue correlating with the decreased level of GLIPR1 expression. Hence, GLIPR1 has been proposed to act as a tumor suppressor that undergoes epigenetic inactivation in prostate cancer.[14][11]
This unique property of GLIPR1 might be effective for the control of malignancies.[15] Preclinical studies has the significant suppression of tumor growth when AdGLIPR1 was directly injected into prostate cancer using an immunocompetent orthotopic mouse model.[15]
# Homology with plant defense mechanism
GLIPR1 exhibits 35% amino acid sequence identity with the tomato pathogenesis-related (PR) protein P14a, which has importance in plant defense mechanism.[16] Comparison of these two protein lead to the identification of a common partially solvent-exposed spatial cluster of four amino acid residues, His-69, Glu-88, Glu-110, and His-127 in the GliPR numeration which indicates a common putative active site for GliPR and PR-1 proteins making a functional link between the human immune system and a plant defense system.[16]
# Cancer types/SNP positions
The graphical representation of number of positions affected by cancer type vs cancer type and number of cancer types vs postiiton in amino acid sequence is provided in the link.[4] | https://www.wikidoc.org/index.php/GLIPR1 | |
f5d7f46862e6396798a5fd0b94233f4e1bc7183f | wikidoc | GOLGA2 | GOLGA2
Golgin subfamily A member 2 is a protein that in humans is encoded by the GOLGA2 gene.
# Function
The Golgi apparatus, which participates in glycosylation and transport of proteins and lipids in the secretory pathway, consists of a series of stacked cisternae (flattened membrane sacs). Interactions between the Golgi and microtubules are thought to be important for the reorganization of the Golgi after it fragments during mitosis. The golgins are a family of proteins, of which the protein encoded by this gene is a member, that are localized to the Golgi. This encoded protein has been postulated to play roles in the stacking of Golgi cisternae and in vesicular transport. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of these variants has not been determined.
A patient with a neuromuscular disorder has been identified that is homozygous for a deletion mutation in this gene, and morpholino knockdown in zebrafish has shown similar phenotypes.
# Interactions
GOLGA2 has been shown to interact with:
- GORASP1,
- GORASP2,
- RAB1A,
- RAB1B and
- RAB2A.
- WAC protein | GOLGA2
Golgin subfamily A member 2 is a protein that in humans is encoded by the GOLGA2 gene.[1]
# Function
The Golgi apparatus, which participates in glycosylation and transport of proteins and lipids in the secretory pathway, consists of a series of stacked cisternae (flattened membrane sacs). Interactions between the Golgi and microtubules are thought to be important for the reorganization of the Golgi after it fragments during mitosis. The golgins are a family of proteins, of which the protein encoded by this gene is a member, that are localized to the Golgi. This encoded protein has been postulated to play roles in the stacking of Golgi cisternae and in vesicular transport. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of these variants has not been determined.[2]
A patient with a neuromuscular disorder has been identified that is homozygous for a deletion mutation in this gene, and morpholino knockdown in zebrafish has shown similar phenotypes.[3]
# Interactions
GOLGA2 has been shown to interact with:
- GORASP1,[4][5][6][7]
- GORASP2,[4][5][6]
- RAB1A,[4][8][9]
- RAB1B[10] and
- RAB2A.[4][11]
- WAC protein[12] | https://www.wikidoc.org/index.php/GOLGA2 | |
dd740a8cbc3d27624b51c80f732b518b1120c5ab | wikidoc | GPR101 | GPR101
Probable G-protein coupled receptor 101 is a protein that in humans is encoded by the GPR101 gene.
G protein-coupled receptors (GPCRs, or GPRs) contain 7 transmembrane domains and transduce extracellular signals through heterotrimeric G proteins.
# Clinical significance
A duplication event in GPR101 is implicated in cases of gigantism and acromegaly. | GPR101
Probable G-protein coupled receptor 101 is a protein that in humans is encoded by the GPR101 gene.[1][2]
G protein-coupled receptors (GPCRs, or GPRs) contain 7 transmembrane domains and transduce extracellular signals through heterotrimeric G proteins.[2]
# Clinical significance
A duplication event in GPR101 is implicated in cases of gigantism and acromegaly.[3] | https://www.wikidoc.org/index.php/GPR101 | |
4315e5852a462cab45a9d05c215b5e95822d0621 | wikidoc | GPR112 | GPR112
G protein-coupled receptor 112 is a protein encoded by the ADGRG4 gene. GPR112 is a member of the adhesion GPCR family.
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.
GPR112 is expressed in human enterochromaffin cells and in the mouse intestine. The N-terminal fragment (NTF) of GPR112 contains pentraxin (PTX)-like modules. GPR112 gene expression has been identified as a marker for neuroendocrine carcinoma cells. | GPR112
G protein-coupled receptor 112 is a protein encoded by the ADGRG4 gene.[1][2] GPR112 is a member of the adhesion GPCR family.[3][4]
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.[5]
GPR112 is expressed in human enterochromaffin cells[6] and in the mouse intestine.[7] The N-terminal fragment (NTF) of GPR112 contains pentraxin (PTX)-like modules.[7] GPR112 gene expression has been identified as a marker for neuroendocrine carcinoma cells.[6] | https://www.wikidoc.org/index.php/GPR112 | |
96e71c65831f78d26e265e7fd6aa3e4da3888ebf | wikidoc | GPR113 | GPR113
GPR113 is a gene that encodes the Probable G-protein coupled receptor 113 protein.
# Gene
The Homo sapiens GPR113 gene is located on chromosome 2 (2p23.3). This gene spans the length of a 38.65kb region from base 26531041 to 26569685 on the negative strand. The GPR113 gene has two neighbors on either side on the negative strand: OTOF otoferlin preceding and HADHA hydroxyacyl-CoA following. Directly opposite the GPR113 on the positive strand is the EPT1 gene.
The GPR113 gene is also known by the aliases PGR23 and HGPCR37.
# Homology & Evolution
The GPR113 has 5 human paralogs GPR110, GPR115, GPR128, GPR111, and GPR116. GPR113 is well conserved in mammals from primates to semi-aquatic species, as well as some amphibians. These include the Common Chimpanzee, the African Bush Elephant, the Platypus, and the Western Clawed Frog. Homologous domains that are well conserved throughout orthologs center in the 7 transmembrane receptor (Secretin family) region highlighted in purple in the figure.
# Protein
The protein product of GPR113 gene is a G-protein coupled receptor. The protein has three transcript variants in humans. Of these three, GPR113 Variant 1 has the longest amino acid sequence, and has the highest identity to orthologs. This leads to the conclusion that GPR113 Variant 1 is the homo sapiens descendent of the ancestral GPR113 gene. GPR113 Var 1 contains 1079 Amino Acids, and is integral to the plasma membrane. The 7-pass receptor contains 4 domains highlighted in the figure at right: Signal Peptide (Red), Hormone Receptor Domain (Blue), Latrophilin/CL-1-like GPS domain (Orange), and the 7-transmembrane receptor (Purple). Between the Hormone Receptor Domain and the GPS is a Domain of unknown function that is not highlighted.
# Function
GPR113 is a G protein-coupled receptor that is involved in a neuropeptide signaling pathway.
# Expression & Disease
GPR113 has been found to be expressed differentially under diseased conditions. Under the condition of Type 2 diabetes, the percentile rank relative to other transcripts decreases relative to normal cell function. The deletion of TP63, which mediates a wide variety of important body processes, also produces decreased GPR113 expression. In mice brains, the cerebellum and the olfactory bulb both show transcription of the GPR113 gene. Additionally, a study from the National Institute of Deafness and Other Communication Disorders has identified GPR113 expression to be highly restricted to a subset of taste receptor cells. This paper's conclusions, coupled with olfactory bulb expression levels, could provide an avenue for future research, potentially illuminating more about GPR113's function.
# Interacting Proteins
GPR113 has been shown to associate with the orphan G protein-coupled receptor GPR123.
## Transcription Factors
# Clinical significance
The clinical significance of this protein has not been established. However, the expression profiles provide exciting directions for future research of the GPR113 gene, especially in fields studying taste and smell. | GPR113
GPR113 is a gene that encodes the Probable G-protein coupled receptor 113 protein.[1][2]
# Gene
The Homo sapiens GPR113 gene is located on chromosome 2 (2p23.3). This gene spans the length of a 38.65kb region from base 26531041 to 26569685 on the negative strand.[3] The GPR113 gene has two neighbors on either side on the negative strand: OTOF otoferlin preceding and HADHA hydroxyacyl-CoA following. Directly opposite the GPR113 on the positive strand is the EPT1 gene.
The GPR113 gene is also known by the aliases PGR23 and HGPCR37.[4]
# Homology & Evolution
The GPR113 has 5 human paralogs GPR110, GPR115, GPR128, GPR111, and GPR116.[4] GPR113 is well conserved in mammals from primates to semi-aquatic species, as well as some amphibians. These include the Common Chimpanzee, the African Bush Elephant, the Platypus, and the Western Clawed Frog.[5] Homologous domains that are well conserved throughout orthologs center in the 7 transmembrane receptor (Secretin family) region highlighted in purple in the figure.[6]
# Protein
The protein product of GPR113 gene is a G-protein coupled receptor. The protein has three transcript variants in humans.[7] Of these three, GPR113 Variant 1 has the longest amino acid sequence, and has the highest identity to orthologs. This leads to the conclusion that GPR113 Variant 1 is the homo sapiens descendent of the ancestral GPR113 gene. GPR113 Var 1 contains 1079 Amino Acids, and is integral to the plasma membrane.[8] The 7-pass receptor contains 4 domains highlighted in the figure at right: Signal Peptide (Red), Hormone Receptor Domain (Blue), Latrophilin/CL-1-like GPS domain (Orange), and the 7-transmembrane receptor (Purple). Between the Hormone Receptor Domain and the GPS is a Domain of unknown function that is not highlighted.
# Function
GPR113 is a G protein-coupled receptor that is involved in a neuropeptide signaling pathway.[8]
# Expression & Disease
GPR113 has been found to be expressed differentially under diseased conditions. Under the condition of Type 2 diabetes, the percentile rank relative to other transcripts decreases relative to normal cell function.[9] The deletion of TP63, which mediates a wide variety of important body processes, also produces decreased GPR113 expression.[10] In mice brains, the cerebellum and the olfactory bulb both show transcription of the GPR113 gene.[11] Additionally, a study from the National Institute of Deafness and Other Communication Disorders has identified GPR113 expression to be highly restricted to a subset of taste receptor cells.[12] This paper's conclusions, coupled with olfactory bulb expression levels, could provide an avenue for future research, potentially illuminating more about GPR113's function.
# Interacting Proteins
GPR113 has been shown to associate with the orphan G protein-coupled receptor GPR123.[13]
## Transcription Factors
# Clinical significance
The clinical significance of this protein has not been established. However, the expression profiles provide exciting directions for future research of the GPR113 gene, especially in fields studying taste and smell. | https://www.wikidoc.org/index.php/GPR113 | |
9692621d2fc3f90b027b3e34fb6935ec96c7ca39 | wikidoc | GPR114 | GPR114
G protein-coupled receptor 114 is a protein encoded by the ADGRG5 gene. GPR114 is a member of the adhesion GPCR family.
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.
GPR114 mRNA is specifically expressed in human eosinophils as well as in mouse lymphocytes, monocytes, macrophage, and dendritic cells.
# Signaling
The cyclic adenosine monophosphate (cAMP) assay in overexpressing HEK293 cells has demonstrated coupling of GPR114 to Gαs protein. | GPR114
G protein-coupled receptor 114 is a protein encoded by the ADGRG5 gene.[1][2][3] GPR114 is a member of the adhesion GPCR family.[4][5]
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.[6]
GPR114 mRNA is specifically expressed in human eosinophils as well as in mouse lymphocytes, monocytes, macrophage, and dendritic cells.[7]
# Signaling
The cyclic adenosine monophosphate (cAMP) assay in overexpressing HEK293 cells has demonstrated coupling of GPR114 to Gαs protein.[8] | https://www.wikidoc.org/index.php/GPR114 | |
8f05a36171a173e419e679e74d6a722c5de4afb1 | wikidoc | GPR119 | GPR119
G protein-coupled receptor 119 also known as GPR119 is a G protein-coupled receptor that in humans is encoded by the GPR119 gene.
GPR119, along with GPR55 and GPR18, have been implicated as novel cannabinoid receptors.
# Pharmacology
GPR119 is expressed predominantly in the pancreas and gastrointestinal tract in rodents and humans, as well as in the brain in rodents. Activation of the receptor has been shown to cause a reduction in food intake and body weight gain in rats. GPR119 has also been shown to regulate incretin and insulin hormone secretion. As a result, new drugs acting on the receptor have been suggested as novel treatments for obesity and diabetes.
# Ligands
A number of endogenous and synthetic ligands for this receptor have been identified:
- 2-Oleoylglycerol
- Anandamide
- AR-231,453
- MBX-2982
- Oleoylethanolamide (Endogenous Ligand)
- PSN-375,963
- PSN-632,408 | GPR119
G protein-coupled receptor 119 also known as GPR119 is a G protein-coupled receptor that in humans is encoded by the GPR119 gene.[1]
GPR119, along with GPR55 and GPR18, have been implicated as novel cannabinoid receptors.[2][3][4]
# Pharmacology
GPR119 is expressed predominantly in the pancreas and gastrointestinal tract in rodents and humans, as well as in the brain in rodents.[5] Activation of the receptor has been shown to cause a reduction in food intake and body weight gain in rats.[5] GPR119 has also been shown to regulate incretin and insulin hormone secretion.[6][7][8] As a result, new drugs acting on the receptor have been suggested as novel treatments for obesity and diabetes.[5][7][9]
# Ligands
A number of endogenous and synthetic ligands for this receptor have been identified:[10][11][12]
- 2-Oleoylglycerol [13]
- Anandamide[9]
- AR-231,453[14]
- MBX-2982[15]
- Oleoylethanolamide[2][5][9] (Endogenous Ligand) [2]
- PSN-375,963[5][6]
- PSN-632,408[5][6] | https://www.wikidoc.org/index.php/GPR119 | |
bd571563800c9eeebec8a647fdc3f62c08225da5 | wikidoc | GPR120 | GPR120
G-protein coupled receptor 120 is a protein that in humans is encoded by the GPR120 gene.
GPR120 is a member of the rhodopsin family of G protein-coupled receptors (GPRs).
GPR120 has also been shown to mediate the anti-inflammatory and insulin-sensitizing effects of omega 3 fatty acids. Lack of GPR120 is responsible for reduced fat metabolism, thereby leading to obesity.
Additionally, GPR120 has been implicated to be involved in the ability to taste fats. It is expressed in taste bud cells (specifically cell type II, which contain other G-protein coupled taste receptors), and its absence leads to reduced preference to two types of fatty acid (linoleic acid and oleic acid), as well as decreased neuronal response to oral fatty acids. | GPR120
G-protein coupled receptor 120 is a protein that in humans is encoded by the GPR120 gene.[1][2]
GPR120 is a member of the rhodopsin family of G protein-coupled receptors (GPRs).[1][2]
GPR120 has also been shown to mediate the anti-inflammatory and insulin-sensitizing effects of omega 3 fatty acids.[3] Lack of GPR120 is responsible for reduced fat metabolism, thereby leading to obesity.[4]
Additionally, GPR120 has been implicated to be involved in the ability to taste fats.[5] It is expressed in taste bud cells (specifically cell type II, which contain other G-protein coupled taste receptors), and its absence leads to reduced preference to two types of fatty acid (linoleic acid and oleic acid), as well as decreased neuronal response to oral fatty acids.[6] | https://www.wikidoc.org/index.php/GPR120 | |
269f3b9f042761d7b5e7e61fa27ac5fec5671b0e | wikidoc | GPR126 | GPR126
G protein-coupled receptor 126 also known as VIGR and DREG is a protein encoded by the ADGRG6 gene. GPR126 is a member of the adhesion GPCR family.
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.
GPR126 is all widely expressed on stromal cells. The N-terminal fragment of GPR126 contains C1r-C1s, Uegf and Bmp1 (CUB), and PTX-like modules.
# Ligand
GPR126 was shown to bind collagen IV and laminin-211 promoting cyclic adenosine monophosphate (cAMP) to mediate myelination.
# Signaling
Upon lipopolysaccharide (LPS) or thrombin stimulation, expression of GPR126 is induced by MAP kinases in endothelial cells. During angiogenesis, GPR126 promotes protein kinase A (PKA)–cAMP-activated signaling in endothelial cells. Forced GPR126 expression in COS-7 cells enhances cAMP levels by coupling to heterotrimeric Gαs/i proteins.
# Function
GPR126 has been identified in genomic regions associated with adult height, more specially trunk height, pulmonary function and adolescent idiopathic scoliosis. In the vertebrate nervous system, many axons are surrounded by a myelin sheath to conduct action potentials rapidly and efficiently. Applying a genetic screen in zebrafish mutants, Talbot’s group demonstrated that GPR126 affects the development of myelinated axons. GPR126 drives the differentiation of Schwann cells through inducing cAMP levels, which causes Oct6 transcriptional activities to promote myelin gene activity. Mutation of gpr126 in zebrafish affects peripheral myelination. Monk’s group demonstrated domain-specific functions of GPR126 during Schwann cells development: the NTF is necessary and sufficient for axon sorting, while the CTF promotes wrapping through cAMP induction to regulate early and late stages of Schwann cells development.
Outside of neurons, GPR126 function is required for heart and inner ear development. GPR126 stimulates VEGF signaling and angiogenesis by modulating VEGF receptor 2 (VEGFR2) expression through STAT5 and GATA2 in endothelial cells.
# Disease
Mouse models have shown GPR126 deletion to affect cartilage biology and spinal column development, supporting findings that variants of GPR126 have been associated with adolescent idiopathic scoliosis, and Mutations have been shown to be responsible for severe arthrogryposis multiplex congenita | GPR126
G protein-coupled receptor 126 also known as VIGR and DREG is a protein encoded by the ADGRG6 gene.[1][2][3] GPR126 is a member of the adhesion GPCR family.[4][5]
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.[6]
GPR126 is all widely expressed on stromal cells.[7] The N-terminal fragment of GPR126 contains C1r-C1s, Uegf and Bmp1 (CUB), and PTX-like modules.[8]
# Ligand
GPR126 was shown to bind collagen IV and laminin-211 promoting cyclic adenosine monophosphate (cAMP) to mediate myelination.[9][10]
# Signaling
Upon lipopolysaccharide (LPS) or thrombin stimulation, expression of GPR126 is induced by MAP kinases in endothelial cells.[8] During angiogenesis, GPR126 promotes protein kinase A (PKA)–cAMP-activated signaling in endothelial cells.[11] Forced GPR126 expression in COS-7 cells enhances cAMP levels by coupling to heterotrimeric Gαs/i proteins.[12]
# Function
GPR126 has been identified in genomic regions associated with adult height, more specially trunk height,[13][14][15] pulmonary function[16] and adolescent idiopathic scoliosis.[17] In the vertebrate nervous system, many axons are surrounded by a myelin sheath to conduct action potentials rapidly and efficiently. Applying a genetic screen in zebrafish mutants, Talbot’s group demonstrated that GPR126 affects the development of myelinated axons.[18] GPR126 drives the differentiation of Schwann cells through inducing cAMP levels, which causes Oct6 transcriptional activities to promote myelin gene activity.[19] Mutation of gpr126 in zebrafish affects peripheral myelination. Monk’s group demonstrated domain-specific functions of GPR126 during Schwann cells development: the NTF is necessary and sufficient for axon sorting, while the CTF promotes wrapping through cAMP induction to regulate early and late stages of Schwann cells development.[10]
Outside of neurons, GPR126 function is required for heart and inner ear development.[20][21][22] GPR126 stimulates VEGF signaling and angiogenesis by modulating VEGF receptor 2 (VEGFR2) expression through STAT5 and GATA2 in endothelial cells.[11]
# Disease
Mouse models have shown GPR126 deletion to affect cartilage biology and spinal column development,[23] supporting findings that variants of GPR126 have been associated with adolescent idiopathic scoliosis,[17] and Mutations have been shown to be responsible for severe arthrogryposis multiplex congenita [24] | https://www.wikidoc.org/index.php/GPR126 | |
bc004be393af2313a962384eeb0ca51d1673b406 | wikidoc | GPR128 | GPR128
G protein-coupled receptor 128 is a protein encoded by the ADGRG7 gene. GPR128 is a member of the adhesion GPCR family.
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.
GPR128 is specifically expressed in human liver as well as in mouse bone marrow and intestinal tissues.
# Function
Ni et al. showed that Gpr128 deletion in mice causes reduced body weight and induced intestinal contraction frequency.
# Clinical significance
A 111-kb copy number gain with breakpoints within the TRK-fused gene (a target of translocations in lymphoma and thyroid tumors) and GPR128 has been identified in the genome of patients with atypical myeloproliferative neoplasms. Notably, the fused gene was also detected in few healthy individuals. | GPR128
G protein-coupled receptor 128 is a protein encoded by the ADGRG7 gene.[1][2][3] GPR128 is a member of the adhesion GPCR family.[4][5]
Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.[6]
GPR128 is specifically expressed in human liver as well as in mouse bone marrow and intestinal tissues.[7]
# Function
Ni et al. showed that Gpr128 deletion in mice causes reduced body weight and induced intestinal contraction frequency.[8]
# Clinical significance
A 111-kb copy number gain with breakpoints within the TRK-fused gene (a target of translocations in lymphoma and thyroid tumors) and GPR128 has been identified in the genome of patients with atypical myeloproliferative neoplasms.[9] Notably, the fused gene was also detected in few healthy individuals. | https://www.wikidoc.org/index.php/GPR128 | |
88144342a985f258dcc7d60ccf30892ff48e9bb4 | wikidoc | GPR132 | GPR132
G protein coupled receptor 132, also termed G2A, is classified as a member of the proton sensing G protein coupled receptor (GPR) subfamily. Like other members of this subfamily, i.e. GPR4, OGR1 (GPR68), and TDAG8 (GPR65), G2A is a G protein coupled receptor that resides in the cell surface membrane, senses changes in extracellular pH, and can alter cellular function as a consequence of these changes. Subsequently, G2A was suggested to be a receptor for lysophosphatidylcholine (LPC). However, the roles of G2A as a pH-sensor or LPC receptor are disputed. Rather, current studies suggest that it is a receptor for certain metabolites of the polyunsaturated fatty acid, linoleic acid.
# The G2A gene
G2A in humans is encoded by the GPR132 gene. The G2A gene (Gene ID: 29933) is located on chromosome 14q32.3 codes for two alternative splice variants, the original one, G2A-a, and G2A-b, that consist of 380 and 371 amino acids, respectively; the two receptor variants, when expressed in Chinese hamster ovary cells, gave very similar results when analyzed for functionality. G2A-a and G2A-b mRNA are expressed at similar levels in blood leukocytes ( macrophages, dendritic cells, neutrophils , mast cells, T lymphocytes and B lymphocytes at the highest levels followed by lower levels in spleen, lung and heart tissues; both variants are expressed at similar levels, and are almost equally induced by DNA synthesis inhibitors (hydroxyurea and cytosine arabinoside) or a differentiation inducer (all-trans retinoic acid) in HL-60 human leukemic cells.
The mouse G2A receptor, encoded by Gpr132, has 67% amino acid identity to human G2A but does not sense pH and does not respond to certain presumptive ligands (i.e. linoleic acid metabolites) that activate the human G2A.
# G2A deficiency in mice
Targeted disruption of G2A in mice causes the development of a late onset (> 1 year) slowly progressive wasting and autoimmune disease characterized by lymphoid organ enlargement, lymphocytic infiltration into various tissues, glomerular immune complex deposition, and anti-nuclear autoantibodies. Mice transplanted with bone marrow cells containing the BCR-ABL leukemia-inducing fusion gene but deficient in G2A exhibit expanded populations of leukemic cells compared to recipients of BCR-ABL-containing, G2A-sufficient bone marrow cells. BCR-ABL is the oncogene of the Philadelphia chromosome that causes human Chronic myelogenous leukemia and is sometimes found associated with human acute lymphocytic leukemia and acute myelocytic leukemia; furthermore, the forced expression of BCR-ABL in cultured rodent cells induces the expression of G2A and the overexpression of G2A inhibits the malignant growth to these cells. Thus, the G2A deficiency studies suggest that G2A functions in mice to suppress certain immune dysfunctions and BCR-ABL-related leukemic cell growth.
# G2A function
## pH sensor
G2A was initially defined as one of the gene products whose production was stimulated in mouse pre-B lymphocytes (see Immunoglobulin heavy chain) by transfecting the cells with the human oncogene (i.e., cancer causing) BCR-ABL or by treating the cells with DNA damaging agents; its expression in these cells blocked their progression through the cell cycle specifically at the G2-M DNA damage checkpoint. These studies allow that G2A limits the potentially malignant growth of certain cells in mice and possible could do so in humans. In addition, Gene knockout studies in mice find G2A to be necessary for suppressing an autoimmune syndrome (see G2A deficiency in mice). These results allow that G2A may function in blocking certain aspects of autoimmunity, particularly those involving the proliferation and tissue trafficking of lymphocytes. Early studies first classified G2A as a proton-sensing receptor and suggested that G2A contributed to the regulation of proliferation in certain cells and the regulation of lymphocytes' contributions to certain immune functions by being activated by changes in extracellular pH. Tissues suffering malignant cell growth, autoimmune reactions, poor blood flow ischemia, inflammation and allergy reactions, and tissue injury develop extracellular acidification due to the stimulation of anaerobic glycolysis; The proton-sensing function of G2A could be involved in combating or, in certain cases promoting these conditions. An example implicating G2A's pH sensitivity in physiological responses involves pain perception. In rats, G2A, similar to other pH sensing GPCRs, is located in dorsal root ganglia neurons, small diameter neurons responsible for nociception, and other nerve tissues responsible for sensing pain; it is suggested that G2A in these nerve tissues detects the acid changes that occur in the extracellular media of injured tissues and signal for the perception of pain
However, the activity of the human G2A receptor and its mouse homolog are significantly less sensitive to pH fluctuations than other pH sensing GPCRs; indeed, in studies of thymocytes and splenocytes taken from mice deficient in either the G2A or another pH-sensing GPCR, TDAG8, TDAG8 was found critical while G2A was found dispensable for sensing pH changes. Thus, the cited functions of G2A presumed due to its pH sensing ability could reflect other means for this receptor's activation.
## Receptor for lyso-phospholipids
A report working with human neutrophils proposed that G2A was a receptor for a phospholipid, lysophosphatidylcholine (LPC), and a Sphingomyelin, sphingosylphosphorylcholine. However, these studies did not give evidence that these lyso-phospholipids actually bound to G2A; some 4 years later this report was withdrawn. Nonetheless, many of LPC's activities do depend on G2A; more recent data suggest that rather than acting directly as a ligand that binds to G2A, LPC alters G2A's distribution within the cell by increasing its movement from the cell interior to the cell surface and/or by preventing its movement away from the cell surface to the cell interior. That is, in neutrophils and other cell types which have internal stores of G2A in membrane-bound secretory vesicles, G2A-containing vesicles continuously merge with and move back out of a cell's surface membrane. Lyso-phospholipids may act as a)) detergents to increase a cell's permeability thereby allowing entry of small extracellular molecules such as ionic calcium which trigger the movement of the intracellular vesicles to the surface membrane or b) agents that intercalate or wedge into the cell's surface membrane to promote this vesicle movement or slow this vesicle movement out of the membrane . Such effects increase the expression of G2A at the cell surface membrane which, if G2A has a sub-stimulatory level of activity when normally express but stimulatory when it is overexpressed at the surface membrane, may lead to G2A-dependent cellular responses. With respect to this view, small decreases in extracellular pH reduce the internalization of G2A thereby increasing its surface membrane expression.
LPCs that contain the unsaturated fatty acids hexadecanoic acid or octadecanoic acid bound to their sn-1 act to permeablize, while LPC with the monounsaturated fatty acid, oleic acid at sn-1 act to perturb target cell surface membranes. While not involving G2A receptor binding, some actions of LPCs are G2A-dependent. For example, LPCs increase the bactericidal activity of rodent neutrophils, enhance hydrogen peroxide production in rodent neutrophils triggered by the ingestion of bacteria, stimulate the chemotaxis of human monocytes, and protect mice from the lethal effects of experimentally induced bacterial sepsis endotoxin. G2A may similarly be responsible for the activities of other phospholipids which, like LPC have not been shown to bind to G2A but still require G2A for certain of their activities viz., lysophosphatidylserine and lysophosphatidylethanolamine; these two lyso-phospholipids stimulate calcium signaling pathways in human neutrophils by a G2A dependent mechanism. Furthermore, activated neutrophils greatly increase their surface membrane content of lysophosphatidylserine. In a mouse model, mouse neutrophils with increased levels of lysophosphatidylserine on their surface membrane due to cell activation or artificial addition showed an increase in there engulfment by mouse macrophages in vitro that was dependent on the expression of G2A in the macrophages and an increased rate of clearance in mice by a mechanism that was dependent on the expression of G2A by the mice. Lysophosphotidylserine-laden neutrophils stimulated the G2A-dependent production the anti-inflammatory mediator, prostaglandin E2, by macrophages in the in vitro studies and inhibited the production of pro-inflammatory mediators, interleukin-6 and keratinocyte chemoattractant, in in vivo studies. Taken together, these studies suggest that G2A, activated by certain phospholipids contributes not only to the development but also the resolution of certain inflammation and innate immune responses in mice and may also do so in humans.
## Receptor for fatty acid metabolites
The linoleic acid metabolites, 9(S)-hydroxyoctadecadienoic acid (HODE), (9R)-HODE, and 13(R)-HODE (see 9-Hydroxyoctadecadienoic acid and 13-Hydroxyoctadecadienoic acid), and the arachidonic acid metabolites 5(S)-hydroxyicosatetraenoic acid (see 5-HETE), 12(S)-HETE (see 12-HETE), 15(S)-HETE (see 15-hydroxyicosatetraenoic acid), and racemic 5-HETE, 12-HETE, 15-HETE, 8-HETE, 9-HETE, and 11-HETE stimulate Chinese hamster ovary cells made to express G2A; these effects, unlike those of phospholipids, appear to involve and require the binding of the metabolites to G2A as evidenced by the ability of the most potent of these metabolites, 9-HODE to stimulate G2A-dependent functions in membranes isolated from these cells. 9-HODE induces cultured normal human epidermal keratinocytes to stop growing by inhibiting their cell cycle at the G1 stage; it also stimulates these cells to secrete three cytokines that stimulate keratinocyte growth vis., interleukin-6, interleukin-8, and GM-CSF. These activities are G2A-dependent. It is suggested that 9-HODE acts in human skin to block the proliferation of damaged cells while concurrently, by triggering the secretion of the cited cytokines, stimulating the proliferation of undamaged skin cells; these actions may thereby serve to rejuvenate skin damaged for example by UV light. | GPR132
G protein coupled receptor 132, also termed G2A, is classified as a member of the proton sensing G protein coupled receptor (GPR) subfamily. Like other members of this subfamily, i.e. GPR4, OGR1 (GPR68), and TDAG8 (GPR65), G2A is a G protein coupled receptor that resides in the cell surface membrane, senses changes in extracellular pH, and can alter cellular function as a consequence of these changes.[1] Subsequently, G2A was suggested to be a receptor for lysophosphatidylcholine (LPC). However, the roles of G2A as a pH-sensor or LPC receptor are disputed. Rather, current studies suggest that it is a receptor for certain metabolites of the polyunsaturated fatty acid, linoleic acid.
# The G2A gene
G2A in humans is encoded by the GPR132 gene.[2][3] The G2A gene (Gene ID: 29933) is located on chromosome 14q32.3 codes for two alternative splice variants, the original one, G2A-a, and G2A-b, that consist of 380 and 371 amino acids, respectively; the two receptor variants, when expressed in Chinese hamster ovary cells, gave very similar results when analyzed for functionality.[4] G2A-a and G2A-b mRNA are expressed at similar levels in blood leukocytes ( macrophages, dendritic cells, neutrophils [PMN], mast cells, T lymphocytes and B lymphocytes at the highest levels followed by lower levels in spleen, lung and heart tissues; both variants are expressed at similar levels, and are almost equally induced by DNA synthesis inhibitors (hydroxyurea and cytosine arabinoside) or a differentiation inducer (all-trans retinoic acid) in HL-60 human leukemic cells.[4][5]
The mouse G2A receptor, encoded by Gpr132, has 67% amino acid identity to human G2A but does not sense pH and does not respond to certain presumptive ligands (i.e. linoleic acid metabolites) that activate the human G2A.[4]
# G2A deficiency in mice
Targeted disruption of G2A in mice causes the development of a late onset (> 1 year) slowly progressive wasting and autoimmune disease characterized by lymphoid organ enlargement, lymphocytic infiltration into various tissues, glomerular immune complex deposition, and anti-nuclear autoantibodies.[6] Mice transplanted with bone marrow cells containing the BCR-ABL leukemia-inducing fusion gene but deficient in G2A exhibit expanded populations of leukemic cells compared to recipients of BCR-ABL-containing, G2A-sufficient bone marrow cells.[2] BCR-ABL is the oncogene of the Philadelphia chromosome that causes human Chronic myelogenous leukemia and is sometimes found associated with human acute lymphocytic leukemia and acute myelocytic leukemia; furthermore, the forced expression of BCR-ABL in cultured rodent cells induces the expression of G2A and the overexpression of G2A inhibits the malignant growth to these cells.[7] Thus, the G2A deficiency studies suggest that G2A functions in mice to suppress certain immune dysfunctions and BCR-ABL-related leukemic cell growth.
# G2A function
## pH sensor
G2A was initially defined as one of the gene products whose production was stimulated in mouse pre-B lymphocytes (see Immunoglobulin heavy chain) by transfecting the cells with the human oncogene (i.e., cancer causing) BCR-ABL or by treating the cells with DNA damaging agents; its expression in these cells blocked their progression through the cell cycle specifically at the G2-M DNA damage checkpoint.[7] These studies allow that G2A limits the potentially malignant growth of certain cells in mice and possible could do so in humans. In addition, Gene knockout studies in mice find G2A to be necessary for suppressing an autoimmune syndrome (see G2A deficiency in mice). These results allow that G2A may function in blocking certain aspects of autoimmunity, particularly those involving the proliferation and tissue trafficking of lymphocytes.[6] Early studies first classified G2A as a proton-sensing receptor and suggested that G2A contributed to the regulation of proliferation in certain cells and the regulation of lymphocytes' contributions to certain immune functions by being activated by changes in extracellular pH.[8] Tissues suffering malignant cell growth, autoimmune reactions, poor blood flow ischemia, inflammation and allergy reactions, and tissue injury develop extracellular acidification due to the stimulation of anaerobic glycolysis; The proton-sensing function of G2A could be involved in combating or, in certain cases promoting these conditions.[5] An example implicating G2A's pH sensitivity in physiological responses involves pain perception. In rats, G2A, similar to other pH sensing GPCRs, is located in dorsal root ganglia neurons, small diameter neurons responsible for nociception, and other nerve tissues responsible for sensing pain; it is suggested that G2A in these nerve tissues detects the acid changes that occur in the extracellular media of injured tissues and signal for the perception of pain[9][5]
However, the activity of the human G2A receptor and its mouse homolog are significantly less sensitive to pH fluctuations than other pH sensing GPCRs; indeed, in studies of thymocytes and splenocytes taken from mice deficient in either the G2A or another pH-sensing GPCR, TDAG8, TDAG8 was found critical while G2A was found dispensable for sensing pH changes.[10] Thus, the cited functions of G2A presumed due to its pH sensing ability could reflect other means for this receptor's activation.
## Receptor for lyso-phospholipids
A report working with human neutrophils proposed that G2A was a receptor for a phospholipid, lysophosphatidylcholine (LPC), and a Sphingomyelin, sphingosylphosphorylcholine.[11] However, these studies did not give evidence that these lyso-phospholipids actually bound to G2A; some 4 years later this report was withdrawn.[12] Nonetheless, many of LPC's activities do depend on G2A; more recent data suggest that rather than acting directly as a ligand that binds to G2A, LPC alters G2A's distribution within the cell by increasing its movement from the cell interior to the cell surface and/or by preventing its movement away from the cell surface to the cell interior. That is, in neutrophils and other cell types which have internal stores of G2A in membrane-bound secretory vesicles, G2A-containing vesicles continuously merge with and move back out of a cell's surface membrane.[13] Lyso-phospholipids may act as a)) detergents to increase a cell's permeability thereby allowing entry of small extracellular molecules such as ionic calcium which trigger the movement of the intracellular vesicles to the surface membrane or b) agents that intercalate or wedge into the cell's surface membrane to promote this vesicle movement or slow this vesicle movement out of the membrane .[13][14] Such effects increase the expression of G2A at the cell surface membrane which, if G2A has a sub-stimulatory level of activity when normally express but stimulatory when it is overexpressed at the surface membrane, may lead to G2A-dependent cellular responses. With respect to this view, small decreases in extracellular pH reduce the internalization of G2A thereby increasing its surface membrane expression.[13]
LPCs that contain the unsaturated fatty acids hexadecanoic acid or octadecanoic acid bound to their sn-1 act to permeablize, while LPC with the monounsaturated fatty acid, oleic acid at sn-1 act to perturb target cell surface membranes.[14] While not involving G2A receptor binding, some actions of LPCs are G2A-dependent. For example, LPCs increase the bactericidal activity of rodent neutrophils, enhance hydrogen peroxide production in rodent neutrophils triggered by the ingestion of bacteria, stimulate the chemotaxis of human monocytes, and protect mice from the lethal effects of experimentally induced bacterial sepsis endotoxin.[15][16] G2A may similarly be responsible for the activities of other phospholipids which, like LPC have not been shown to bind to G2A but still require G2A for certain of their activities viz., lysophosphatidylserine and lysophosphatidylethanolamine; these two lyso-phospholipids stimulate calcium signaling pathways in human neutrophils by a G2A dependent mechanism.[14] Furthermore, activated neutrophils greatly increase their surface membrane content of lysophosphatidylserine. In a mouse model, mouse neutrophils with increased levels of lysophosphatidylserine on their surface membrane due to cell activation or artificial addition showed an increase in there engulfment by mouse macrophages in vitro that was dependent on the expression of G2A in the macrophages and an increased rate of clearance in mice by a mechanism that was dependent on the expression of G2A by the mice.[17][18] Lysophosphotidylserine-laden neutrophils stimulated the G2A-dependent production the anti-inflammatory mediator, prostaglandin E2, by macrophages in the in vitro studies and inhibited the production of pro-inflammatory mediators, interleukin-6 and keratinocyte chemoattractant, in in vivo studies. Taken together, these studies suggest that G2A, activated by certain phospholipids contributes not only to the development but also the resolution of certain inflammation and innate immune responses in mice and may also do so in humans.
## Receptor for fatty acid metabolites
The linoleic acid metabolites, 9(S)-hydroxyoctadecadienoic acid (HODE), (9R)-HODE, and 13(R)-HODE (see 9-Hydroxyoctadecadienoic acid and 13-Hydroxyoctadecadienoic acid),[4][16] and the arachidonic acid metabolites 5(S)-hydroxyicosatetraenoic acid (see 5-HETE), 12(S)-HETE (see 12-HETE), 15(S)-HETE (see 15-hydroxyicosatetraenoic acid), and racemic 5-HETE, 12-HETE, 15-HETE, 8-HETE, 9-HETE, and 11-HETE stimulate Chinese hamster ovary cells made to express G2A; these effects, unlike those of phospholipids, appear to involve and require the binding of the metabolites to G2A as evidenced by the ability of the most potent of these metabolites, 9-HODE to stimulate G2A-dependent functions in membranes isolated from these cells.[4] 9-HODE induces cultured normal human epidermal keratinocytes to stop growing by inhibiting their cell cycle at the G1 stage; it also stimulates these cells to secrete three cytokines that stimulate keratinocyte growth vis., interleukin-6, interleukin-8, and GM-CSF. These activities are G2A-dependent. It is suggested that 9-HODE acts in human skin to block the proliferation of damaged cells while concurrently, by triggering the secretion of the cited cytokines, stimulating the proliferation of undamaged skin cells; these actions may thereby serve to rejuvenate skin damaged for example by UV light.[4] | https://www.wikidoc.org/index.php/GPR132 | |
512c14f3d7ee58832a3aa91921e90a30eb244517 | wikidoc | GPR158 | GPR158
Probable G-protein coupled receptor 158 is a protein that in humans is encoded by the GPR158 gene.
# Function
This protein is an orphan class C GPCR. It is highly expressed in the brain, where it binds to RGS7, an inhibitor of Gi/o-coupled GPCR signaling, localizing it to the plasma membrane.
It is expressed at lower levels in other organs and shows an unusual subcellular localization pattern, being found at both the plasma membrane and in the nucleus.
# Clinical significance
## Role in mood regulation
GPR158 in the medial prefrontal cortex (mPFC) has been shown to regulate stress-induced depression in a mouse model of depression and has been found to be upregulated in post-mortem tissue samples from humans with major depressive disorder (MDD).
## Role in prostate cancer
The GPR158 gene is an androgen-regulated gene that stimulates cell proliferation in prostate cancer cell lines, and it is linked to neuroendocrine differentiation. | GPR158
Probable G-protein coupled receptor 158 is a protein that in humans is encoded by the GPR158 gene.[1]
# Function
This protein is an orphan class C GPCR. It is highly expressed in the brain, where it binds to RGS7, an inhibitor of Gi/o-coupled GPCR signaling, localizing it to the plasma membrane.[2]
It is expressed at lower levels in other organs and shows an unusual subcellular localization pattern, being found at both the plasma membrane and in the nucleus.[3]
# Clinical significance
## Role in mood regulation
GPR158 in the medial prefrontal cortex (mPFC) has been shown to regulate stress-induced depression in a mouse model of depression and has been found to be upregulated in post-mortem tissue samples from humans with major depressive disorder (MDD).[4]
## Role in prostate cancer
The GPR158 gene is an androgen-regulated gene that stimulates cell proliferation in prostate cancer cell lines, and it is linked to neuroendocrine differentiation.[5] | https://www.wikidoc.org/index.php/GPR158 | |
c47d646f08d8c7e08e11e874853efc6d07c0a69f | wikidoc | GPR182 | GPR182
GPR182 (or G protein-coupled receptor 182) is a human gene (and associated protein) which is an orphan G-protein coupled receptor.
When this gene was first cloned, it was proposed to encode an adrenomedullin receptor. However, when the corresponding protein was expressed, it was found not to respond to adrenomedullin (ADM).
It was subsequently shown that a different GPCR, CALCRL when complexed with RAMP2 can function as an ADM receptor. | GPR182
GPR182 (or G protein-coupled receptor 182) is a human gene (and associated protein) which is an orphan G-protein coupled receptor.[1]
When this gene was first cloned, it was proposed to encode an adrenomedullin receptor.[2] However, when the corresponding protein was expressed, it was found not to respond to adrenomedullin (ADM).[3]
It was subsequently shown that a different GPCR, CALCRL when complexed with RAMP2 can function as an ADM receptor.[4] | https://www.wikidoc.org/index.php/GPR182 | |
b674c7585c206399a21a6be018cf79578008c2b4 | wikidoc | GPR183 | GPR183
G-protein coupled receptor 183 also known as Epstein-Barr virus-induced G-protein coupled receptor 2 (EBI2) is a protein that in humans is encoded by the GPR183 gene.
This gene was identified by the up-regulation of its expression upon Epstein-Barr virus infection of the Burkitt's lymphoma cell line BL41. This gene is predicted to encode a G protein-coupled receptor that is most closely related to the thrombin receptor. Expression of this gene was detected in B-lymphocyte cell lines and lymphoid tissues but not in T-lymphocyte cell lines or peripheral blood T lymphocytes.
EBI2 helps B cell homing within a lymph node. EBI2 expression increases during B cell activation, after B cell receptor and CD40 stimulation; its expression decreases during germinal cell development due to BCL6--a transcription factor required in germinal center development. EBI2 must turn off to move B cells to the germinal center from the periphery, and must turn on for B cells to exit the germinal center and re-enter the periphery. EBI2 is a receptor for oxysterols, the most potent activator being 7α,25-dihydroxycholesterol. | GPR183
G-protein coupled receptor 183 also known as Epstein-Barr virus-induced G-protein coupled receptor 2 (EBI2) is a protein that in humans is encoded by the GPR183 gene.[1]
This gene was identified by the up-regulation of its expression upon Epstein-Barr virus infection of the Burkitt's lymphoma cell line BL41.[2] This gene is predicted to encode a G protein-coupled receptor that is most closely related to the thrombin receptor. Expression of this gene was detected in B-lymphocyte cell lines and lymphoid tissues but not in T-lymphocyte cell lines or peripheral blood T lymphocytes.[1]
EBI2 helps B cell homing within a lymph node. EBI2 expression increases during B cell activation, after B cell receptor and CD40 stimulation; its expression decreases during germinal cell development due to BCL6--a transcription factor required in germinal center development. EBI2 must turn off to move B cells to the germinal center from the periphery, and must turn on for B cells to exit the germinal center and re-enter the periphery.[3] EBI2 is a receptor for oxysterols, the most potent activator being 7α,25-dihydroxycholesterol.[4] | https://www.wikidoc.org/index.php/GPR183 | |
5ca4fc636bda791ecc9eb62ec455880331e2fc5e | wikidoc | GPRC5A | GPRC5A
Retinoic acid-induced protein 3 is a protein that in humans is encoded by the GPRC5A gene.
# Function
This gene encodes a member of the type 3 G protein-coupled receptor family, characterized by the signature 7-transmembrane domain motif. The encoded protein may be involved in interaction between retinoic acid and G protein signalling pathways. Retinoic acid plays a critical role in development, cellular growth, and differentiation. This gene may play a role in embryonic development and epithelial cell differentiation.
# Post transcriptional regulation
GPRC5A is one of only a handful of genes known in the literature that are post-transcriptionally controlled by miRNAs through their 5'UTR.
# Clinical significance
GPRC5A is dysregulated in many human cancers and in other diseases. | GPRC5A
Retinoic acid-induced protein 3 is a protein that in humans is encoded by the GPRC5A gene.[1][2]
# Function
This gene encodes a member of the type 3 G protein-coupled receptor family, characterized by the signature 7-transmembrane domain motif. The encoded protein may be involved in interaction between retinoic acid and G protein signalling pathways. Retinoic acid plays a critical role in development, cellular growth, and differentiation. This gene may play a role in embryonic development and epithelial cell differentiation.[2]
# Post transcriptional regulation
GPRC5A is one of only a handful of genes known in the literature that are post-transcriptionally controlled by miRNAs through their 5'UTR.[3]
# Clinical significance
GPRC5A is dysregulated in many human cancers and in other diseases.[4] | https://www.wikidoc.org/index.php/GPRC5A | |
2fda39fb60d08a7e66d900f4821abf7066e49354 | wikidoc | GRIN2A | GRIN2A
Glutamate receptor subunit epsilon-1 is a protein that in humans is encoded by the GRIN2A gene.
# Function
N-methyl-D-aspartate (NMDA) receptors are a class of ionotropic glutamate receptors. NMDA channel has been shown to be involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. NMDA receptor channels are heteromers composed of the key receptor subunit NMDAR1 (GRIN1) and 1 or more of the 4 NMDAR2 subunits: NMDAR2A (GRIN2A), NMDAR2B (GRIN2B), NMDAR2C (GRIN2C), and NMDAR2D (GRIN2D).
# Associations
Variants of the gene are associated with the protective effect of coffee on Parkinson's disease.
Mutations in GRIN2A are associated to refractory epilepsy.
Whole exome/genome sequencing has led to the discovery of an association between mutations in GRIN2A and a wide variety of neurological diseases, including epilepsy, intellectual disability, autism spectrum disorders, developmental delay, and schizophrenia.
# Interactions
GRIN2A has been shown to interact with:
- DLG1
- DLG3
- DLG4
- FYN
- Interleukin 16
- PTK2B
- Src | GRIN2A
Glutamate [NMDA] receptor subunit epsilon-1 is a protein that in humans is encoded by the GRIN2A gene.[1]
# Function
N-methyl-D-aspartate (NMDA) receptors are a class of ionotropic glutamate receptors. NMDA channel has been shown to be involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. NMDA receptor channels are heteromers composed of the key receptor subunit NMDAR1 (GRIN1) and 1 or more of the 4 NMDAR2 subunits: NMDAR2A (GRIN2A), NMDAR2B (GRIN2B), NMDAR2C (GRIN2C), and NMDAR2D (GRIN2D).[2]
# Associations
Variants of the gene are associated with the protective effect of coffee on Parkinson's disease.[3][4]
Mutations in GRIN2A are associated to refractory epilepsy.[5]
Whole exome/genome sequencing has led to the discovery of an association between mutations in GRIN2A and a wide variety of neurological diseases, including epilepsy, intellectual disability, autism spectrum disorders, developmental delay, and schizophrenia.[6]
# Interactions
GRIN2A has been shown to interact with:
- DLG1[7]
- DLG3[8][9]
- DLG4[8][9][10][11][12]
- FYN[10][13][14][15]
- Interleukin 16[16]
- PTK2B[17][18]
- Src[13][15] | https://www.wikidoc.org/index.php/GRIN2A | |
2147421b6a2c048bdb1c42ca73868acb74e3a4f7 | wikidoc | GRIN2B | GRIN2B
Glutamate receptor subunit epsilon-2, also known as N-methyl D-aspartate receptor subtype 2B (NMDAR2B or NR2B), is a protein that in humans is encoded by the GRIN2B gene.
# NMDA receptors
N-methyl-D-aspartate (NMDA) receptors are a class of ionotropic glutamate receptors. The NMDA receptor channel has been shown to be involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. NMDA receptor channels are heterotetramers composed of two molecules of the key receptor subunit NMDAR1 (GRIN1) and two drawn from one or more of the four NMDAR2 subunits: NMDAR2A (GRIN2A), NMDAR2B (GRIN2B), NMDAR2C (GRIN2C), and NMDAR2D (GRIN2D). The NR2 subunit acts as the agonist binding site for glutamate, one of the predominant excitatory neurotransmitter receptors in the mammalian brain.
# Function
NR2B has been associated with age- and visual-experience-dependent plasticity in the neocortex of rats, where an increased NR2B/NR2A ratio correlates directly with the stronger excitatory LTP in young animals. This is thought to contribute to experience-dependent refinement of developing cortical circuits.
Both mice and rats that were engineered to over-express GRIN2B in their brains have increased mental ability.
# Ligands
- Besonprodil
- CERC-301, a selective NR2B receptor antagonist
- Eliprodil
- Evt 101, a selective NR2B receptor antagonist. This compound was tested as a potentially fast-acting antidepressant. In 2011 it was voluntarily withdrawn from a Phase II clinical study in treatment-resistant depression due to an unsatisfactory toxicity profile.
- Felbamate, an anticonvulsant that is also a positive allosteric modulator for the GABAA receptor
- Ro-25-6981 (also known as MI-4), a selective NR2B receptor antagonist
- Traxoprodil, a selective NR2B receptor antagonist
# Interactions
GRIN2B has been shown to interact with:
- Actinin, alpha 2,
- DLG2,
- DLG3,
- DLG4,
- EXOC4,
- LIN7B, and
- RICS. | GRIN2B
Glutamate [NMDA] receptor subunit epsilon-2, also known as N-methyl D-aspartate receptor subtype 2B (NMDAR2B or NR2B), is a protein that in humans is encoded by the GRIN2B gene.[1]
# NMDA receptors
N-methyl-D-aspartate (NMDA) receptors are a class of ionotropic glutamate receptors. The NMDA receptor channel has been shown to be involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. NMDA receptor channels are heterotetramers composed of two molecules of the key receptor subunit NMDAR1 (GRIN1) and two drawn from one or more of the four NMDAR2 subunits: NMDAR2A (GRIN2A), NMDAR2B (GRIN2B), NMDAR2C (GRIN2C), and NMDAR2D (GRIN2D). The NR2 subunit acts as the agonist binding site for glutamate, one of the predominant excitatory neurotransmitter receptors in the mammalian brain.[2]
# Function
NR2B has been associated with age- and visual-experience-dependent plasticity in the neocortex of rats, where an increased NR2B/NR2A ratio correlates directly with the stronger excitatory LTP in young animals. This is thought to contribute to experience-dependent refinement of developing cortical circuits.[3]
Both mice and rats that were engineered to over-express GRIN2B in their brains have increased mental ability.[4][5]
# Ligands
- Besonprodil
- CERC-301, a selective NR2B receptor antagonist
- Eliprodil
- Evt 101, a selective NR2B receptor antagonist. This compound was tested as a potentially fast-acting antidepressant.[6] In 2011 it was voluntarily withdrawn from a Phase II clinical study in treatment-resistant depression due to an unsatisfactory toxicity profile.[7]
- Felbamate, an anticonvulsant that is also a positive allosteric modulator for the GABAA receptor
- Ro-25-6981 (also known as MI-4), a selective NR2B receptor antagonist
- Traxoprodil, a selective NR2B receptor antagonist
# Interactions
GRIN2B has been shown to interact with:
- Actinin, alpha 2,[8]
- DLG2,[9][10]
- DLG3,[9][10][11][12]
- DLG4,[9][10][11][12][13][14]
- EXOC4,[11]
- LIN7B,[15] and
- RICS.[16] | https://www.wikidoc.org/index.php/GRIN2B | |
e58ff0032b2e5121fed2e109b054db65fc75603a | wikidoc | GRXCR1 | GRXCR1
Glutaredoxin domain-containing cysteine-rich protein 1 is a protein that in humans is encoded by the GRXCR1 gene.
This gene is one of 60 loci associated with autosomal-recessive nonsyndromic hearing impairment. This gene encodes a protein which contains GRX-like domains; these domains play a role in the S-glutathionylation of proteins and may be involved in actin organization in hair cells.
# Model organisms
Model organisms have been used in the study of GRXCR1 function. A mutant mouse line, called tasmanian devil (Grxcr1tde) was generated. Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty four tests were carried out on mutant mice and thirteen significant abnormalities were observed. Homozygous mutant animals of both sex displayed decreased body weights, grip strength, body fat, body length and plasma immunoglobulins, abnormal open field test and modified SHIRPA behaviour, and severe hearing impairment at 13 weeks. Male homozygous mutant animals additionally showed abnormal indirect calorimetry and clinical chemistry parameters, improved glucose tolerance and a decreased leukocyte cell number. Female homozygotes also had an increased response to stress-induced hyperthermia and a significantly reduced monocyte percentage. | GRXCR1
Glutaredoxin domain-containing cysteine-rich protein 1 is a protein that in humans is encoded by the GRXCR1 gene.[1]
This gene is one of 60 loci associated with autosomal-recessive nonsyndromic hearing impairment.[2] This gene encodes a protein which contains GRX-like domains; these domains play a role in the S-glutathionylation of proteins and may be involved in actin organization in hair cells.[1]
# Model organisms
Model organisms have been used in the study of GRXCR1 function. A mutant mouse line, called tasmanian devil (Grxcr1tde[16]) was generated. Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.[14][17] Twenty four tests were carried out on mutant mice and thirteen significant abnormalities were observed.[14] Homozygous mutant animals of both sex displayed decreased body weights, grip strength, body fat, body length and plasma immunoglobulins, abnormal open field test and modified SHIRPA behaviour, and severe hearing impairment at 13 weeks. Male homozygous mutant animals additionally showed abnormal indirect calorimetry and clinical chemistry parameters, improved glucose tolerance and a decreased leukocyte cell number. Female homozygotes also had an increased response to stress-induced hyperthermia and a significantly reduced monocyte percentage.[14] | https://www.wikidoc.org/index.php/GRXCR1 | |
f02e4b6c27a907f93c784527b68035617fac40f6 | wikidoc | GTF2H2 | GTF2H2
General transcription factor IIH subunit 2 is a protein that in humans is encoded by the GTF2H2 gene.
# Function
This gene is part of a 500 kb inverted duplication on chromosome 5q13. This duplicated region contains at least four genes and repetitive elements which make it prone to rearrangements and deletions. The repetitiveness and complexity of the sequence have also caused difficulty in determining the organization of this genomic region. This gene is within the telomeric copy of the duplication. Deletion of this gene sometimes accompanies deletion of the neighboring SMN1 gene in spinal muscular atrophy (SMA) patients but it is unclear if deletion of this gene contributes to the SMA phenotype. This gene encodes the 44 kDa subunit of RNA polymerase II transcription initiation factor IIH which is involved in basal transcription and nucleotide excision repair. Transcript variants for this gene have been described, but their full length nature has not been determined. A second copy of this gene within the centromeric copy of the duplication has been described in the literature. It is reported to be different by either two or four base pairs; however, no sequence data is currently available for the centromeric copy of the gene.
# Interactions
GTF2H2 has been shown to interact with GTF2H5, XPB and ERCC2. | GTF2H2
General transcription factor IIH subunit 2 is a protein that in humans is encoded by the GTF2H2 gene.[1][2]
# Function
This gene is part of a 500 kb inverted duplication on chromosome 5q13. This duplicated region contains at least four genes and repetitive elements which make it prone to rearrangements and deletions. The repetitiveness and complexity of the sequence have also caused difficulty in determining the organization of this genomic region. This gene is within the telomeric copy of the duplication. Deletion of this gene sometimes accompanies deletion of the neighboring SMN1 gene in spinal muscular atrophy (SMA) patients but it is unclear if deletion of this gene contributes to the SMA phenotype. This gene encodes the 44 kDa subunit of RNA polymerase II transcription initiation factor IIH which is involved in basal transcription and nucleotide excision repair. Transcript variants for this gene have been described, but their full length nature has not been determined. A second copy of this gene within the centromeric copy of the duplication has been described in the literature. It is reported to be different by either two or four base pairs; however, no sequence data is currently available for the centromeric copy of the gene.[2]
# Interactions
GTF2H2 has been shown to interact with GTF2H5,[3][4] XPB[3][5] and ERCC2.[4][6] | https://www.wikidoc.org/index.php/GTF2H2 | |
1495d40b4966b76ed4b13bb217b50730d2533f9b | wikidoc | GTF3C5 | GTF3C5
General transcription factor 3C polypeptide 5 is a protein that in humans is encoded by the GTF3C5 gene.
# Model organisms
Model organisms have been used in the study of GTF3C5 function. A conditional knockout mouse line, called Gtf3c5tm2a(KOMP)Wtsi was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty four tests were carried out on mutant mice and two significant abnormalities were observed. No homozygous mutant embryos were identified during gestation, and therefore none survived until weaning. The remaining tests were carried out on heterozygous mutant adult mice; no additional significant abnormalities were observed in these animals.
# Interactions
GTF3C5 has been shown to interact with GTF3C2 and GTF3C4. | GTF3C5
General transcription factor 3C polypeptide 5 is a protein that in humans is encoded by the GTF3C5 gene.[1][2]
# Model organisms
Model organisms have been used in the study of GTF3C5 function. A conditional knockout mouse line, called Gtf3c5tm2a(KOMP)Wtsi[7][8] was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.[9][10][11]
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.[5][12] Twenty four tests were carried out on mutant mice and two significant abnormalities were observed.[5] No homozygous mutant embryos were identified during gestation, and therefore none survived until weaning. The remaining tests were carried out on heterozygous mutant adult mice; no additional significant abnormalities were observed in these animals.[5]
# Interactions
GTF3C5 has been shown to interact with GTF3C2[1] and GTF3C4.[13] | https://www.wikidoc.org/index.php/GTF3C5 | |
4c7bf1d9af6d329a4655d0491c3f12dd43b872ed | wikidoc | GTPBP3 | GTPBP3
tRNA modification GTPase GTPBP3, mitochondrial is an enzyme that in human is encoded by the GTPBP3 gene on chromosome 19.
The GTPBP3 gene encodes a GTP-binding protein that is evolutionarily conserved from bacteria to mammals and which is localized to the mitochondrion and functions in tRNA modification. At least two major isoforms due to alternative splicing are known In addition, a polymorphism on valine 250 is known and may influence aminoglydoside-induced deafness.
# Structure
The GTPBP3 gene contains 10 exons, and encodes a ~44 kDa GTP-binding protein that is evolutionarily conserved from bacteria to mammals. The N-terminal domain of mitochondrial tRNA modification GTPase mediates the dimerization of the protein in a potassium-independent manner, which is thought to be related to the construction of the binding site for the one-carbon-unit donor in its tRNA modification reaction function.
# Function
Mitochondrial tRNA modification GTPase is thought to catalyze the formation of 5-taurinomethyluridine (τm(5)U) in the anticodon wobble position of five mitochondrial tRNA. The gene was first discovered yeast where the mutation of the yeast homolog of human GTPBP3, MSS1, is found to elicit respiratory defect in yeast only when the mitochondrial 155 rRNA P(R)454 is present. The latter is equivalent to the human 12 rRNA A1555G mutation which has been found to associate with deafness. Hence GTPBP3 and its yeast homolog function in modification of mitochondrial function. In human, GTPBP3 is ubiquitously expressed in multiple tissues in multiple transcripts. As a tRNA modification enzyme, it is thought to function to modify codon-anticodon interaction, which is consistent with its modification of the severity of phenotypes in 12S rRNA A1555G mutation..
# Clinical Significance
Mutations in GTPBP3 are known to cause hypertrophic cardiomyopathy and mitochondrial defects. Individuals with homozygous or compound heterozygous mutations in GTPBP3 present with combined deficiency of respiratory chain complexes in skeletal muscle, which require mitochondrial translation of mitochondrial-encoded complex subunits to assemble. GTPBP3 mutations cause severe mitochondrial translation defect. The majority of characterized subjects presented with lactic acidosis and hypertrophic cardiomyopathy.
The valine 250 polymorphisms on GTPBP3 is associated with severity of aminoglycoside-induced deafness in human, a disease associated with homoplasmic A1555G mutation in the mitochondrial-encoded 12S rRNA and is characterized by deafness, varying from profond congenital hearing loss to normal hearing. | GTPBP3
tRNA modification GTPase GTPBP3, mitochondrial is an enzyme that in human is encoded by the GTPBP3 gene on chromosome 19.[1][2]
The GTPBP3 gene encodes a GTP-binding protein that is evolutionarily conserved from bacteria to mammals [3] and which is localized to the mitochondrion and functions in tRNA modification.[2] At least two major isoforms due to alternative splicing are known In addition, a polymorphism on valine 250 is known and may influence aminoglydoside-induced deafness.[2]
# Structure
The GTPBP3 gene contains 10 exons,[2] and encodes a ~44 kDa GTP-binding protein that is evolutionarily conserved from bacteria to mammals.[3] The N-terminal domain of mitochondrial tRNA modification GTPase mediates the dimerization of the protein in a potassium-independent manner,[4] which is thought to be related to the construction of the binding site for the one-carbon-unit donor in its tRNA modification reaction function.[4]
# Function
Mitochondrial tRNA modification GTPase is thought to catalyze the formation of 5-taurinomethyluridine (τm(5)U) in the anticodon wobble position of five mitochondrial tRNA.[5] The gene was first discovered yeast where the mutation of the yeast homolog of human GTPBP3, MSS1, is found to elicit respiratory defect in yeast only when the mitochondrial 155 rRNA P(R)454 is present. The latter is equivalent to the human 12 rRNA A1555G mutation which has been found to associate with deafness. Hence GTPBP3 and its yeast homolog function in modification of mitochondrial function. In human, GTPBP3 is ubiquitously expressed in multiple tissues in multiple transcripts.[3] As a tRNA modification enzyme, it is thought to function to modify codon-anticodon interaction, which is consistent with its modification of the severity of phenotypes in 12S rRNA A1555G mutation..
# Clinical Significance
Mutations in GTPBP3 are known to cause hypertrophic cardiomyopathy and mitochondrial defects.[5] Individuals with homozygous or compound heterozygous mutations in GTPBP3 present with combined deficiency of respiratory chain complexes in skeletal muscle,[5] which require mitochondrial translation of mitochondrial-encoded complex subunits to assemble. GTPBP3 mutations cause severe mitochondrial translation defect. The majority of characterized subjects presented with lactic acidosis and hypertrophic cardiomyopathy.
The valine 250 polymorphisms on GTPBP3 is associated with severity of aminoglycoside-induced deafness in human, a disease associated with homoplasmic A1555G mutation in the mitochondrial-encoded 12S rRNA and is characterized by deafness, varying from profond congenital hearing loss to normal hearing. | https://www.wikidoc.org/index.php/GTPBP3 | |
d997125ba1c6a143a076f06994b82da3489342f2 | wikidoc | GUCY2D | GUCY2D
Retinal guanylyl cyclase 1 also known as guanylate cyclase 2D, retinal is an enzyme that in humans is encoded by the GUCY2D (guanylate cyclase 2D) gene.
# Function
This gene encodes a retina-specific guanylate cyclase, which is a member of the membrane guanylyl cyclase family. Like other membrane guanylyl cyclases, this enzyme has a hydrophobic amino-terminal signal sequence followed by a large extracellular domain, a single membrane spanning domain, a kinase homology domain, and a guanylyl cyclase catalytic domain. In contrast to other membrane guanylyl cyclases, this enzyme is not activated by natriuretic peptides.
# Clinical significance
Mutations in this gene result in Leber's congenital amaurosis and cone-rod dystrophy-6 diseases. | GUCY2D
Retinal guanylyl cyclase 1 also known as guanylate cyclase 2D, retinal is an enzyme that in humans is encoded by the GUCY2D (guanylate cyclase 2D) gene.[1]
# Function
This gene encodes a retina-specific guanylate cyclase, which is a member of the membrane guanylyl cyclase family. Like other membrane guanylyl cyclases, this enzyme has a hydrophobic amino-terminal signal sequence followed by a large extracellular domain, a single membrane spanning domain, a kinase homology domain, and a guanylyl cyclase catalytic domain. In contrast to other membrane guanylyl cyclases, this enzyme is not activated by natriuretic peptides.
# Clinical significance
Mutations in this gene result in Leber's congenital amaurosis and cone-rod dystrophy-6 diseases.[2] | https://www.wikidoc.org/index.php/GUCY2D | |
0c639e7c3b76a4052c07a242588d9fb7e8328a5f | wikidoc | GUCY2F | GUCY2F
Retinal guanylyl cyclase 2 also known as guanylate cyclase F (GUCY2F) is a protein that in humans is encoded by the GUCY2F gene.
# Function
The protein encoded by this gene is a guanylyl cyclase found predominantly in photoreceptors in the retina. The encoded protein is thought to be involved in resynthesis of cGMP after light activation of the visual signal transduction cascade, allowing a return to the dark state. This protein is a single-pass type I membrane protein.
# Clinical significance
Defects in this gene may be a cause of X-linked retinitis pigmentosa. | GUCY2F
Retinal guanylyl cyclase 2 also known as guanylate cyclase F (GUCY2F) is a protein that in humans is encoded by the GUCY2F gene.[1]
# Function
The protein encoded by this gene is a guanylyl cyclase found predominantly in photoreceptors in the retina. The encoded protein is thought to be involved in resynthesis of cGMP after light activation of the visual signal transduction cascade, allowing a return to the dark state. This protein is a single-pass type I membrane protein.[1]
# Clinical significance
Defects in this gene may be a cause of X-linked retinitis pigmentosa.[1] | https://www.wikidoc.org/index.php/GUCY2F | |
7a418a862b9e5b2cb40960102ec6c5a80e8b6ce6 | wikidoc | Gadd45 | Gadd45
The Growth Arrest and DNA Damage gadd45 genes, including GADD45A (originally termed gadd45) GADD45B (originally termed MyD118), & GADD45G (originally termed CR6) are implicated as stress sensors that modulate the response of mammalian cells to genotoxic/physiological stress, and modulate tumor formation. Gadd45 proteins interact with other proteins implicated in stress responses, including PCNA, p21, Cdc2/CyclinB1, MEKK4 & p38 kinase.
# History
Gadd45a was discovered & characterized in the laboratory of Dr. Albert Fornace Jr. in 1988.
Gadd45b (MyD118) was discovered & characterized in the laboratories of Drs Dan A.Liebermann & Barbara Hoffman in 1991.
Gadd45g (CR6) was discovered & characterized in the laboratories of Drs Keneneth Smith Dan A.Liebermann & Barbara Hoffman in 1993 & 1999. | Gadd45
Template:Wikify
The Growth Arrest and DNA Damage gadd45 genes, including GADD45A (originally termed gadd45) GADD45B (originally termed MyD118), & GADD45G (originally termed CR6) are implicated as stress sensors that modulate the response of mammalian cells to genotoxic/physiological stress, and modulate tumor formation. Gadd45 proteins interact with other proteins implicated in stress responses, including PCNA, p21, Cdc2/CyclinB1, MEKK4 & p38 kinase.[1] [2]
# History
Gadd45a was discovered & characterized in the laboratory of Dr. Albert Fornace Jr. in 1988. [3]
Gadd45b (MyD118) was discovered & characterized in the laboratories of Drs Dan A.Liebermann & Barbara Hoffman in 1991.[4]
Gadd45g (CR6) was discovered & characterized in the laboratories of Drs Keneneth Smith Dan A.Liebermann & Barbara Hoffman in 1993 & 1999.[5]
[6] | https://www.wikidoc.org/index.php/Gadd45 | |
6065c61492e99985cfb943b5479be1b504322b5a | wikidoc | Gallon | Gallon
A gallon is a measure of volume. It is in current use in the United States and still has limited use in many other English-speaking countries.
Historically the gallon has had many different definitions, but there are three definitions in current use. These are the U.S. liquid gallon, the U.S. dry gallon and the Imperial (UK) gallon.
# Definitions
- U.S. liquid gallon is legally defined as 231 cubic inches, and is equal to (exactly) 3.785411784 litres (1 L = 10-3 m3) or about 0.13368 cubic feet. This is the most common definition of a gallon in the United States. The U.S. fluid ounce is defined as 1/128 of a U.S. gallon.
- U.S. dry gallon is one-eighth of a U.S. Winchester bushel of 2150.42 cubic inches, thus 268.8025 cubic inches (exactly) or 4.40488377086 litres (exactly). The U.S. dry gallon is less commonly used.
- Imperial (UK) gallon is legally defined as 4.54609 litres (≈ 277.42 cu in), which is about 1.2 U.S. liquid gallons. This definition is used in Commonwealth countries and Ireland, and is based on the volume of 10 pounds of water at 62 °F. (A U.S. liquid gallon of water weighs about 8.33 pounds at the same temperature.)
# Worldwide usage of gallons
The US liquid gallon continues to be used as a unit of measure for fuel
in
Belize,
Colombia,
Dominican Republic,
Ecuador,
El Salvador,
Grenada,
Guatemala,
Haiti,
Honduras,
Myanmar (Burma),
Nicaragua,
Panama,
Peru,
Puerto Rico,
Sierra Leone,
and the United States.
The Imperial gallon is no longer legal in the United Kingdom for trade or public administration purposes, but it is used colloquially (and in advertising) for the fuel consumption (inverted) figures, in miles per gallon (elsewhere in Europe, the effective fuel consumption is most often advertized in litres per 100 km). However it continues to be used as a unit of measure for fuel in
Antigua and Barbuda,
Guyana,
and the United Arab Emirates.
The word has also been used as translation for several foreign units of the same magnitude.
# Subdivisions
The gallons in current use are subdivided into eight pints or four quarts. Pints are further subdivided into fluid ounces and liquid gallons are also subdivided into 32 gills, i.e. a quarter of a pint. The sub-units of pint and fluid ounce, despite having the same name in both Imperial and U.S. units, differ in volume and are therefore not interchangeable.
The Imperial fluid ounce is defined as 1/160 of an Imperial gallon.
# History
At one time, the volume of a gallon depended on what was being measured, and where it was being measured. But, by the end of the 18th century, three definitions were in common use:
- The corn gallon, or “Winchester gallon”, of about 268.8 cubic inches (≈ 4.405 L),
- the wine gallon, or “Queen Anne’s gallon”, which was 231 cubic inches (≈ 3.79 L), and
- the ale gallon of 282 cubic inches (≈ 4.62 L).
The corn or dry gallon was used in the United States until recently for grain and other dry commodities. It is one eighth of the (Winchester) bushel, originally a cylindrical measure of 18½ inches in diameter and 8 inches depth. That made the dry gallon 9¼²·π in³ ≈ 268.80252 cubic inches. The bushel, which like dry quart and pint still sees some use, was later defined to be 2150.42 cubic inches exactly, making its gallon 268.8025 cubic inches exactly (4.40488377086 L).
In previous centuries there had been a corn gallon of around 271 to 272 cubic inches.
The wine, fluid, or liquid gallon is the standard U.S. gallon since the early 19th century. The wine gallon, which some sources relate to the volume occupied by eight medieval merchant pounds of wine, was at one time defined as the volume of a cylinder six inches deep and seven inches in diameter, i.e. 6·3½²·π ≈ 230.90706 cubic inches. It had been redefined during the reign of Queen Anne, in 1706, as 231 cubic inches exactly (3 × 7 × 11 in), which is the result of the earlier definition with π approximated to 22⁄7. Although the wine gallon had been used for centuries for import duty purposes there was no legal standard of it in the Exchequer and a smaller gallon (224 cu in) was actually in use, so this statute became necessary. It remains the U.S. definition today.
The original ratio between corn and wine gallon is 9¼²:6·3½² = 1369:1176, but 268.8:231 is exactly 64:55 or ca. 13:11. This approximation is still applicable, although the ratio of 1.164115646 slightly changed to 1.163647186 with current definitions (268.8025:231 = 107521:92400 ≈ 1344:1165).
In some contexts it is or was necessary to disambiguate between those two U.S. gallons, so “liquid” or “fluid” and “dry” respectively are then added to the name.
In 1824, Britain adopted a close approximation to the ale gallon known as the Imperial gallon and abolished all other gallons in favour of it. Inspired by the kilogram-litre relationship, the Imperial gallon was based on the volume of 10 pounds of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied by 10 pounds of distilled water of density 0.998859 grams per millilitre weighed in air of density 0.001217 g/mL against weights of density 8.136 g/mL. This works out at approximately 4.5460903 L (277.4416 cu in). The metric definition of exactly 4.54609 cubic decimetres (also 4.54609 L after the litre was redefined in 1964, ca. 277.419433 cu in) was adopted shortly afterwards in Canada; for several years, the conventional value of 4.546092 L was used in the United Kingdom, until the Canadian convention was adopted in 1985.
Before and into the 19th century there were also several other gallons in use, with varying definitions. These are summarized in the table below. During some eras, the gallon was based on an exact conversion with a linear measure cubed. Other eras, the gallon was based on a rational approximation to the volume of a cylinder that could be used as a standard container, such as a basket, barrel, or jar. Other definitions were based on the density of a commodity, occasionally water, but more often a more marketable good such as wine or oats. Given these options and the variety of cultures that have used the gallon, it is not surprising that the exact value has drifted over the centuries.
## Examples of gallons | Gallon
A gallon is a measure of volume. It is in current use in the United States and still has limited use in many other English-speaking countries.
Historically the gallon has had many different definitions, but there are three definitions in current use. These are the U.S. liquid gallon, the U.S. dry gallon and the Imperial (UK) gallon.
# Definitions
- U.S. liquid gallon is legally defined as 231 cubic inches, and is equal to (exactly) 3.785411784 litres (1 L = 10-3 m3) or about 0.13368 cubic feet. This is the most common definition of a gallon in the United States. The U.S. fluid ounce is defined as 1/128 of a U.S. gallon.
- U.S. dry gallon is one-eighth of a U.S. Winchester bushel of 2150.42 cubic inches, thus 268.8025 cubic inches (exactly) or 4.40488377086 litres (exactly). The U.S. dry gallon is less commonly used.
- Imperial (UK) gallon is legally defined as 4.54609 litres (≈ 277.42 cu in), which is about 1.2 U.S. liquid gallons. This definition is used in Commonwealth countries and Ireland, and is based on the volume of 10 pounds of water at 62 °F. (A U.S. liquid gallon of water weighs about 8.33 pounds at the same temperature.)
# Worldwide usage of gallons
The US liquid gallon continues to be used as a unit of measure for fuel[1]
in
Belize,[2][3]
Colombia,
Dominican Republic,
Ecuador,
El Salvador,
Grenada,
Guatemala,
Haiti,
Honduras,
Myanmar (Burma),[4][5][6]
Nicaragua,
Panama,
Peru,
Puerto Rico,
Sierra Leone,
and the United States.
The Imperial gallon is no longer legal in the United Kingdom for trade or public administration purposes, but it is used colloquially (and in advertising) for the fuel consumption (inverted) figures, in miles per gallon (elsewhere in Europe, the effective fuel consumption is most often advertized in litres per 100 km). However it continues to be used as a unit of measure for fuel[1] in
Antigua and Barbuda,[7][8][9]
Guyana,
and the United Arab Emirates.
The word has also been used as translation for several foreign units of the same magnitude.[citation needed]
# Subdivisions
The gallons in current use are subdivided into eight pints or four quarts. Pints are further subdivided into fluid ounces and liquid gallons are also subdivided into 32 gills, i.e. a quarter of a pint. The sub-units of pint and fluid ounce, despite having the same name in both Imperial and U.S. units, differ in volume and are therefore not interchangeable.
The Imperial fluid ounce is defined as 1/160 of an Imperial gallon.
# History
At one time, the volume of a gallon depended on what was being measured, and where it was being measured. But, by the end of the 18th century, three definitions were in common use:
- The corn gallon, or “Winchester gallon”, of about 268.8 cubic inches (≈ 4.405 L),
- the wine gallon, or “Queen Anne’s gallon”, which was 231 cubic inches (≈ 3.79 L), and
- the ale gallon of 282 cubic inches (≈ 4.62 L).
The corn or dry gallon was used in the United States until recently for grain and other dry commodities. It is one eighth of the (Winchester) bushel, originally a cylindrical measure of 18½ inches in diameter and 8 inches depth. That made the dry gallon 9¼²·π in³ ≈ 268.80252 cubic inches. The bushel, which like dry quart and pint still sees some use, was later defined to be 2150.42 cubic inches exactly, making its gallon 268.8025 cubic inches exactly (4.40488377086 L).
In previous centuries there had been a corn gallon of around 271 to 272 cubic inches.
The wine, fluid, or liquid gallon is the standard U.S. gallon since the early 19th century. The wine gallon, which some sources relate to the volume occupied by eight medieval merchant pounds of wine, was at one time defined as the volume of a cylinder six inches deep and seven inches in diameter, i.e. 6·3½²·π ≈ 230.90706 cubic inches. It had been redefined during the reign of Queen Anne, in 1706, as 231 cubic inches exactly (3 × 7 × 11 in), which is the result of the earlier definition with π approximated to 22⁄7. Although the wine gallon had been used for centuries for import duty purposes there was no legal standard of it in the Exchequer and a smaller gallon (224 cu in) was actually in use, so this statute became necessary. It remains the U.S. definition today.
The original ratio between corn and wine gallon is 9¼²:6·3½² = 1369:1176, but 268.8:231 is exactly 64:55 or ca. 13:11. This approximation is still applicable, although the ratio of 1.164115646 slightly changed to 1.163647186 with current definitions (268.8025:231 = 107521:92400 ≈ 1344:1165).
In some contexts it is or was necessary to disambiguate between those two U.S. gallons, so “liquid” or “fluid” and “dry” respectively are then added to the name.
In 1824, Britain adopted a close approximation to the ale gallon known as the Imperial gallon and abolished all other gallons in favour of it. Inspired by the kilogram-litre relationship, the Imperial gallon was based on the volume of 10 pounds of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied by 10 pounds of distilled water of density 0.998859 grams per millilitre weighed in air of density 0.001217 g/mL against weights of density 8.136 g/mL. This works out at approximately 4.5460903 L (277.4416 cu in). The metric definition of exactly 4.54609 cubic decimetres (also 4.54609 L after the litre was redefined in 1964, ca. 277.419433 cu in) was adopted shortly afterwards in Canada; for several years, the conventional value of 4.546092 L was used in the United Kingdom, until the Canadian convention was adopted in 1985.
Before and into the 19th century there were also several other gallons in use, with varying definitions. These are summarized in the table below. During some eras, the gallon was based on an exact conversion with a linear measure cubed. Other eras, the gallon was based on a rational approximation to the volume of a cylinder that could be used as a standard container, such as a basket, barrel, or jar. Other definitions were based on the density of a commodity, occasionally water, but more often a more marketable good such as wine or oats. Given these options and the variety of cultures that have used the gallon, it is not surprising that the exact value has drifted over the centuries.
## Examples of gallons | https://www.wikidoc.org/index.php/Gallon | |
6dcb12552f9040f4ab0821ca1fd95761805e9c6d | wikidoc | Gamete | Gamete
# Overview
A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete—called an ovum (or egg)—and a male produces the smaller type—called a sperm. This is an example of anisogamy or heterogamy, the condition wherein females and males produce gametes of different sizes. In contrast, isogamy is the state of gametes from both sexes being the same size.
The name gamete was introduced by the Austrian biologist Gregor Mendel.
# Creation
The creation of gametes is termed gametogenesis, during which phase gametocytes divide by meiosis into gametes. Meiosis reduces the number of sets of chromosomes from two to one (i.e., produces haploid gametes from diploid gametocytes). Organs that produce gametes are called gonads in animals, and archegonia or antheridia in plants.
# Gamete cycle
A gamete of one generation ultimately creates a gametes in the next generation, but still keeping the same quantity of genetic information.
Gametes are haploid cells; that is, they contain one complete set of chromosomes (the actual number varies from species to species). When two gametes fuse (in animals typically involving a sperm and an egg), they form a zygote—a cell that has two complete sets of chromosomes and therefore is diploid. The zygote receives one set of chromosomes from each of the two gametes through the fusion of the two gamete nuclei. After multiple cell divisions and cellular differentiation, a zygote develops, first into an embryo, and ultimately into a mature individual capable of producing gametes.
# Dissimilarity
In contrast to a gamete, the diploid somatic cells of an individual contain one copy of the chromosome set from the sperm and one copy of the chromosome set from the egg; that is, the cells of the offspring have genes expressing characteristics of both the father and the mother. A gamete's chromosomes are not exact duplicates of either of the sets of chromosomes carried in the somatic cells of the individual that produced the gametes. They can be hybrids produced through crossover(a form of genetic recombination) of chromosomes, which takes place in meiosis. This hybridization has a random element, and the chromosomes tend to be a little different in every gamete that an individual produces. This recombination and the fact that the two chromosome sets ultimately come from either a grandmother or a grandfather on each parental side account for the genetic dissimilarity of sibling's.
cs:Pohlavní buňka
da:Gamet
de:Gamet
eo:Gameto
it:Gamete
he:תא רבייה
lt:Gameta
mk:Гамета
nl:Gameet
no:Kjønnscelle
sk:Pohlavná bunka
sv:Könscell
th:แกมีต | Gamete
# Overview
A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete—called an ovum (or egg)—and a male produces the smaller type—called a sperm. This is an example of anisogamy or heterogamy, the condition wherein females and males produce gametes of different sizes. In contrast, isogamy is the state of gametes from both sexes being the same size.
The name gamete was introduced by the Austrian biologist Gregor Mendel.
# Creation
The creation of gametes is termed gametogenesis, during which phase gametocytes divide by meiosis into gametes. Meiosis reduces the number of sets of chromosomes from two to one (i.e., produces haploid gametes from diploid gametocytes). Organs that produce gametes are called gonads in animals, and archegonia or antheridia in plants.
# Gamete cycle
A gamete of one generation ultimately creates a gametes in the next generation, but still keeping the same quantity of genetic information.
Gametes are haploid cells; that is, they contain one complete set of chromosomes (the actual number varies from species to species). When two gametes fuse (in animals typically involving a sperm and an egg), they form a zygote—a cell that has two complete sets of chromosomes and therefore is diploid. The zygote receives one set of chromosomes from each of the two gametes through the fusion of the two gamete nuclei. After multiple cell divisions and cellular differentiation, a zygote develops, first into an embryo, and ultimately into a mature individual capable of producing gametes.
# Dissimilarity
In contrast to a gamete, the diploid somatic cells of an individual contain one copy of the chromosome set from the sperm and one copy of the chromosome set from the egg; that is, the cells of the offspring have genes expressing characteristics of both the father and the mother. A gamete's chromosomes are not exact duplicates of either of the sets of chromosomes carried in the somatic cells of the individual that produced the gametes. They can be hybrids produced through crossover(a form of genetic recombination) of chromosomes, which takes place in meiosis. This hybridization has a random element, and the chromosomes tend to be a little different in every gamete that an individual produces. This recombination and the fact that the two chromosome sets ultimately come from either a grandmother or a grandfather on each parental side account for the genetic dissimilarity of sibling's.
Template:Anatomy-stub
cs:Pohlavní buňka
da:Gamet
de:Gamet
eo:Gameto
it:Gamete
he:תא רבייה
lt:Gameta
mk:Гамета
nl:Gameet
no:Kjønnscelle
sk:Pohlavná bunka
sv:Könscell
th:แกมีต
Template:Jb1
Template:WH
Template:WikiDoc Sources | https://www.wikidoc.org/index.php/Gamete | |
f57322ff04acc516e3b7d908b5b92df32abc71db | wikidoc | Garlic | Garlic
Allium sativum L., commonly known as garlic, is a species in the onion family Alliaceae. Its close relatives include the onion, shallot, and leek.
Garlic has been used throughout recorded history for both culinary and medicinal purposes. It has a characteristic pungent, 'hot', flavour that mellows and sweetens considerably with cooking. A 'head' of garlic, the most commonly used plant part, comprises numerous discrete 'cloves'. The leaves and stems are sometimes eaten, particularly while immature and tender.
So-called elephant garlic is a different species (a form of leek).
# Origin and distribution
The ancestry of cultivated garlic, according to Zohary and Hopf, is not definitely established: "a difficulty in the identification of its wild progenitor is the sterility of the cultivars."
Allium sativum grows in the wild in areas where it has become naturalised; it probably descended from the species Allium longicuspis, which grows wild in south-western Asia. The 'wild garlic', 'crow garlic' and 'field garlic' of Britain are the species Allium ursinum, Allium vineale and Aleum oleraceum, respectively. In North America, 'Allium vineale, known as 'wild-' or 'crow garlic', and Allium candadensis, known as 'meadow-' or 'wild garlic', are common weeds in fields.
# Uses
## Culinary uses
Garlic is widely used around the world for its pungent flavour, as a seasoning or condiment. Depending on the form of cooking, the flavor is either mellow or intense. It is often paired with onion, tomato, or ginger. The parchment-like skin is much like the skin of an onion, and is typically removed before using in raw or cooked form. An alternative is to coat heads of garlic and roast them in the oven. The garlic softens and can be extracted from individual cloves by squeezing one end.
Oils are often flavored with garlic cloves. Commercially prepared oils are widely available, but when preparing garlic-infused oil at home, there is a risk of botulism if the product is not stored properly. To reduce this risk, the oil should be refrigerated and used within one week. Manufacturers add chemicals and/or acids to eliminate the risk of botulism in their products.
In Chinese cuisine, the young bulbs are pickled for 3–6 weeks in a mixture of sugar, salt and spices. In Russia and the Caucasus, the shoots are pickled and eaten as an appetizer.
Immature scapes are tender and edible. They are also known as 'garlic spears', 'stems', or 'tops'. Scapes generally have a milder taste than cloves. They are often used in stir frying or prepared like asparagus. Garlic leaves are a popular vegetable in many parts of Asia, particularly Chinese, Vietnamese, Cambodian and Korean cuisines. The leaves are cut, cleaned and then stir-fried with eggs, meat, or vegetables.
Garlic is essential to several Mediterranean dishes.
Mixing garlic with eggs and olive oil produces aioli ("garlic and oil" in Provençal). The Spanish variant does not use eggs. Garlic, oil, and a chunky base produce skordalia (from the Greek and Italian names of garlic). Blending garlic, almond, oil and soaked bread produces ajoblanco (ajo blanco is Spanish for "white garlic"). Le Tourin is a French garlic soup.
## Storage
Domestically, garlic is stored warm (above 18°C) and dry, to keep it dormant (so that it does not sprout).
It is traditionally hung; softneck varieties are often braided in strands called "plaits", or in short plaits called "grappes"
Pictures.
Commercially, garlic is stored at 0°C, also dry .
## Historical use
From the earliest times garlic has been used as a food. It formed part of the diet of the Israelites in Egypt (Numbers 11:5) and of the labourers employed by Khufu in constructing the pyramid. Garlic is still grown in Egypt, but the Syrian variety is the kind most esteemed now (see Rawlinson's Herodotus, 2.125).
It was consumed by the ancient Greek and Roman soldiers, sailors and rural classes (Virgil, Ecologues ii. 11), and, according to Pliny the Elder (Natural History xix. 32), by the African peasantry. Galen eulogizes it as the "rustic's theriac" (cure-all) (see F Adams's Paulus Aegineta, p. 99), and Alexander Neckam, a writer of the 12th century (see Wright's edition of his works, p. 473, 1863), recommends it as a palliative of the heat of the sun in field labor.
In his Natural History Pliny gives an exceedingly long list of scenarios in which it was considered beneficial (N.H. xx. 23). Dr. T. Sydenham valued it as an application in confluent smallpox, and, says Cullen (Mat. Med. ii. p. 174, 1789), found some dropsies cured by it alone. Early in the 20th century, it was sometimes used in the treatment of pulmonary tuberculosis or phthisis.
Garlic was rare in traditional English cuisine (though it is said to have been grown in England before 1548), and has been a much more common ingredient in Mediterranean Europe. Garlic was placed by the ancient Greeks on the piles of stones at cross-roads, as a supper for Hecate (Theophrastus, Characters, The Superstitious Man); and according to Pliny, garlic and onions were invoked as deities by the Egyptians at the taking of oaths. The inhabitants of Pelusium in lower Egypt, who worshipped the onion, are said to have had an aversion to both onions and garlic as food.
To prevent the plant from running to leaf, Pliny (N.H. xix. 34) advised bending the stalk downward and covering with earth; seeding, he observes, may be prevented by twisting the stalk (by "seeding", he most likely means the development of small, less potent bulbs).
## Medicinal use and health benefits
Garlic has been used as both food and medicine in many cultures for thousands of years, dating as far back as the time that the Egyptian pyramids were built. Garlic is claimed to help prevent heart disease including atherosclerosis, high cholesterol, high blood pressure, and cancer.
Animal studies, and some early investigational studies in humans, have suggested possible cardiovascular benefits of garlic. A Czech study found garlic supplementation reduced accumulation of cholesterol on vascular walls of animals. Another study had similar results, with garlic supplementation significantly reducing the placque in the aortas of cholesterol-fed rabbits. Another study showed that supplementation with garlic extract inhibited vascular calcification in human patients with high blood cholesterol.
However, a NIH-funded randomized clinical trial published in Archives of Internal Medicine in 2007 found that consumption of garlic, in any form, did not reduce cholesterol levels in patients with moderately high baseline levels.
With regard to this clinical trial, Heart.org reports:
Despite decades of research suggesting that garlic can improve cholesterol profiles, a new NIH-funded trial found absolutely no effects of raw garlic or garlic supplements on LDL, HDL, or triglycerides... The findings underscore the hazards of meta-analyses made up of small, flawed studies and the value of rigorously studying popular herbal remedies.
In 2007 a BBC news story reported that Allium sativum may have beneficial properties, such as preventing and fighting the common cold. This assertion has the backing of long tradition. Traditional British herbalism used garlic for hoarseness and coughs, both as a syrup and in a salve made of garlic and lard, which was rubbed on the chest and back. The Cherokee also used it as an expectorant for coughs and croup.
Allium sativum has been found to reduce platelet aggregation and hyperlipidemia.
Garlic is also alleged to help regulate blood sugar levels. Regular and prolonged use of therapeutic amounts of aged garlic extracts lower blood homocysteine levels, and has shown to prevent some complications of diabetes mellitus. People taking insulin should not consume medicinal amounts of garlic without consulting a physician. In such applications, garlic must be fresh and uncooked, or the allicin will be lost.
Allium sativum may also possess cancer-fighting properties due to the presence of allylic sulfur compounds such as diallyl disulfide (DADs), believed to be an anticarcinogen.
In 1858, Louis Pasteur observed garlic's antibacterial activity, and it was used as an antiseptic to prevent gangrene during World War I and World War II. More recently it has been found from a clinical trial that a mouthwash containing 2.5% fresh garlic shows good antimicrobial activity, although the majority of the participants reported an unpleasant taste and halitosis.
In modern naturopathy, garlic is used as a treatment for intestinal worms and other intestinal parasites, both orally and as an anal suppository. Garlic cloves are used as a remedy for infections (especially chest problems), digestive disorders, and fungal infections such as thrush.
Garlic supplementation in rats along with a high protein diet has been shown to boost testosterone levels.
# Properties
When crushed, Allium sativum yields allicin, a powerful antibiotic and anti-fungal compound (phytoncide). It also contains alliin, ajoene, enzymes, vitamin B, minerals, and flavonoids.
The percentage composition of the bulbs is given by E. Solly (Trans. Hon. Soc. Loud., new ser., iii. p. 60) as water 84.09%, organic matter 13.38%, and inorganic matter 1.53% - that of the leaves being water 87.14%, organic matter 11.27% and inorganic matter 1.59%.
The phytochemicals responsible for the sharp flavor of garlic are produced when the plant's cells are damaged. When a cell is broken by chopping, chewing, or crushing, enzymes stored in cell vacuoles trigger the breakdown of several sulfur-containing compounds stored in the cell fluids. The resultant compounds are responsible for the sharp or hot taste and strong smell of garlic. Some of the compounds are unstable and continue to evolve over time. Among the members of the onion family, garlic has by far the highest concentrations of initial reaction products, making garlic much more potent than onions, shallots, or leeks. Although people have come to enjoy the taste of garlic, these compounds are believed to have evolved as a defensive mechanism, deterring animals like birds, insects, and worms from eating the plant.
A large number of sulfur compounds contribute to the smell and taste of garlic. Diallyl disulfide is believed to be an important odour component. Allicin has been found to be the compound most responsible for the spiciness of raw garlic. This chemical opens thermoTRP (transient receptor potential) channels that are responsible for the burning sense of heat in foods. The process of cooking garlic removes allicin, thus mellowing its spiciness.
When eaten in quantity, garlic may be strongly evident in the diner's sweat and breath the following day. This is because garlic's strong smelling sulfur compounds are metabolized forming allyl methyl sulfide. Allyl methyl sulfide (AMS) cannot be digested and is passed into the blood. It is carried to the lungs and the skin where it is excreted. Since digestion takes several hours, and release of AMS several hours more, the effect of eating garlic may be present for a long time.
This well-known phenomenon of "garlic breath" is alleged to be alleviated by eating fresh parsley. The herb is, therefore, included in many garlic recipes, such as Pistou and Persillade. However, since the odour results mainly from digestive processes placing compounds such as AMS in the blood, and AMS is then released through the lungs over the course of many hours, eating parsley provides only a temporary masking. One way of accelerating the release of AMS from the body is the use of a sauna. Due to its strong odor, garlic is sometimes called the "stinking rose".
Because garlic passes into the bloodstream, it can be a useful mosquito repellent. This is most likely the cause of the myth that vampires hate garlic.
# Superstition and mythology
Garlic has been regarded as a force for both good and evil. A Christian myth considers that after Satan left the Garden of Eden, garlic arose in his left footprint, and onion in the right. In Europe, many cultures have used garlic for protection or white magic, perhaps owing to its reputation as a potent preventative medicine. Central European folk beliefs considered garlic a powerful ward against demons, werewolves, and vampires. To ward off vampires, garlic could be worn, hung in windows or rubbed on chimneys and keyholes.
The association of garlic to evil spirits may be based on the antibacterial, antiparasitic value of garlic, which could prevent infections that lead to delusions, and other related mental illness symptoms.
# Cautions
- Known adverse effects of garlic include halitosis (non-bacterial), indigestion, nausea, emesis and diarrhea.
- Garlic should not be taken with warfarin, antiplatelets, saquinavir, antihypertensives, or hypoglycemic drugs.
- Cases of botulism have been caused by consuming garlic-in-oil preparations. It is important to add acid when creating these mixtures and to keep them refrigerated to retard bacterial growth.
- Whilst culinary quantities are considered safe during pregnancy and breastfeeding, extremely large quantities of garlic and garlic supplements have been linked with a raised risk of bleeding. Garlic may cause abortion. Some breastfeeding mothers have found their babies slow to feed and have noted a garlic odour coming from their baby when they have consumed garlic.
- The side effects of long-term garlic supplementation, if any exist, are largely unknown and no FDA-approved study has been performed. However, garlic has been consumed for several thousand years without any adverse long-term effects, suggesting that modest quantities of garlic pose, at worst, minimal risks to normal individuals.
- There have been several reports of serious burns resulting from garlic being applied topically for various purposes, including naturopathic uses and acne treatment. On the basis of numerous reports of such burns, including burns to children, topical use of raw garlic, as well as insertion of raw garlic into body cavities is strongly discouraged and could lead to serious injury. In particular, topical application of raw garlic to young children is extremely risky. | Garlic
Allium sativum L., commonly known as garlic, is a species in the onion family Alliaceae. Its close relatives include the onion, shallot, and leek.
Garlic has been used throughout recorded history for both culinary and medicinal purposes. It has a characteristic pungent, 'hot', flavour that mellows and sweetens considerably with cooking.[1] A 'head' of garlic, the most commonly used plant part, comprises numerous discrete 'cloves'. The leaves and stems are sometimes eaten, particularly while immature and tender.
So-called elephant garlic is a different species (a form of leek).
# Origin and distribution
The ancestry of cultivated garlic, according to Zohary and Hopf, is not definitely established: "a difficulty in the identification of its wild progenitor is the sterility of the cultivars."[2]
Allium sativum grows in the wild in areas where it has become naturalised; it probably descended from the species Allium longicuspis, which grows wild in south-western Asia.[3] The 'wild garlic', 'crow garlic' and 'field garlic' of Britain are the species Allium ursinum, Allium vineale and Aleum oleraceum, respectively. In North America, 'Allium vineale, known as 'wild-' or 'crow garlic', and Allium candadensis, known as 'meadow-' or 'wild garlic', are common weeds in fields.[4]
# Uses
## Culinary uses
Garlic is widely used around the world for its pungent flavour, as a seasoning or condiment. Depending on the form of cooking, the flavor is either mellow or intense. It is often paired with onion, tomato, or ginger. The parchment-like skin is much like the skin of an onion, and is typically removed before using in raw or cooked form. An alternative is to coat heads of garlic and roast them in the oven. The garlic softens and can be extracted from individual cloves by squeezing one end.
Oils are often flavored with garlic cloves. Commercially prepared oils are widely available, but when preparing garlic-infused oil at home, there is a risk of botulism if the product is not stored properly. To reduce this risk, the oil should be refrigerated and used within one week. Manufacturers add chemicals and/or acids to eliminate the risk of botulism in their products.[5]
In Chinese cuisine, the young bulbs are pickled for 3–6 weeks in a mixture of sugar, salt and spices. In Russia and the Caucasus, the shoots are pickled and eaten as an appetizer.
Immature scapes are tender and edible. They are also known as 'garlic spears', 'stems', or 'tops'. Scapes generally have a milder taste than cloves. They are often used in stir frying or prepared like asparagus. Garlic leaves are a popular vegetable in many parts of Asia, particularly Chinese, Vietnamese, Cambodian and Korean cuisines. The leaves are cut, cleaned and then stir-fried with eggs, meat, or vegetables.
Garlic is essential to several Mediterranean dishes.
Mixing garlic with eggs and olive oil produces aioli ("garlic and oil" in Provençal). The Spanish variant does not use eggs. Garlic, oil, and a chunky base produce skordalia (from the Greek and Italian names of garlic). Blending garlic, almond, oil and soaked bread produces ajoblanco (ajo blanco is Spanish for "white garlic"). Le Tourin is a French garlic soup.
## Storage
Domestically, garlic is stored warm (above 18°C) and dry, to keep it dormant (so that it does not sprout).
It is traditionally hung; softneck varieties are often braided in strands called "plaits", or in short plaits called "grappes"
Pictures.
Commercially, garlic is stored at 0°C, also dry [6].
## Historical use
From the earliest times garlic has been used as a food. It formed part of the diet of the Israelites in Egypt (Numbers 11:5) and of the labourers employed by Khufu in constructing the pyramid. Garlic is still grown in Egypt, but the Syrian variety is the kind most esteemed now (see Rawlinson's Herodotus, 2.125).
It was consumed by the ancient Greek and Roman soldiers, sailors and rural classes (Virgil, Ecologues ii. 11), and, according to Pliny the Elder (Natural History xix. 32), by the African peasantry. Galen eulogizes it as the "rustic's theriac" (cure-all) (see F Adams's Paulus Aegineta, p. 99), and Alexander Neckam, a writer of the 12th century (see Wright's edition of his works, p. 473, 1863), recommends it as a palliative of the heat of the sun in field labor.
In his Natural History Pliny gives an exceedingly long list of scenarios in which it was considered beneficial (N.H. xx. 23). Dr. T. Sydenham valued it as an application in confluent smallpox, and, says Cullen (Mat. Med. ii. p. 174, 1789), found some dropsies cured by it alone. Early in the 20th century, it was sometimes used in the treatment of pulmonary tuberculosis or phthisis.
Garlic was rare in traditional English cuisine (though it is said to have been grown in England before 1548), and has been a much more common ingredient in Mediterranean Europe. Garlic was placed by the ancient Greeks on the piles of stones at cross-roads, as a supper for Hecate (Theophrastus, Characters, The Superstitious Man); and according to Pliny, garlic and onions were invoked as deities by the Egyptians at the taking of oaths. The inhabitants of Pelusium in lower Egypt, who worshipped the onion, are said to have had an aversion to both onions and garlic as food.
To prevent the plant from running to leaf, Pliny (N.H. xix. 34) advised bending the stalk downward and covering with earth; seeding, he observes, may be prevented by twisting the stalk (by "seeding", he most likely means the development of small, less potent bulbs).
## Medicinal use and health benefits
Garlic has been used as both food and medicine in many cultures for thousands of years, dating as far back as the time that the Egyptian pyramids were built. Garlic is claimed to help prevent heart disease including atherosclerosis, high cholesterol, high blood pressure, and cancer.[8]
Animal studies, and some early investigational studies in humans, have suggested possible cardiovascular benefits of garlic. A Czech study found garlic supplementation reduced accumulation of cholesterol on vascular walls of animals.[9] Another study had similar results, with garlic supplementation significantly reducing the placque in the aortas of cholesterol-fed rabbits.[10] Another study showed that supplementation with garlic extract inhibited vascular calcification in human patients with high blood cholesterol.[11]
However, a NIH-funded randomized clinical trial published in Archives of Internal Medicine in 2007 found that consumption of garlic, in any form, did not reduce cholesterol levels in patients with moderately high baseline levels.[12][13]
With regard to this clinical trial, Heart.org reports:
Despite decades of research suggesting that garlic can improve cholesterol profiles, a new NIH-funded trial found absolutely no effects of raw garlic or garlic supplements on LDL, HDL, or triglycerides... The findings underscore the hazards of meta-analyses made up of small, flawed studies and the value of rigorously studying popular herbal remedies.[14]
In 2007 a BBC news story reported that Allium sativum may have beneficial properties, such as preventing and fighting the common cold.[15] This assertion has the backing of long tradition. Traditional British herbalism used garlic for hoarseness and coughs, both as a syrup and in a salve made of garlic and lard, which was rubbed on the chest and back.[16] The Cherokee also used it as an expectorant for coughs and croup.[17]
Allium sativum has been found to reduce platelet aggregation and hyperlipidemia.[18][19]
Garlic is also alleged to help regulate blood sugar levels. Regular and prolonged use of therapeutic amounts of aged garlic extracts lower blood homocysteine levels, and has shown to prevent some complications of diabetes mellitus.[20][21] People taking insulin should not consume medicinal amounts of garlic without consulting a physician. In such applications, garlic must be fresh and uncooked, or the allicin will be lost.
Allium sativum may also possess cancer-fighting properties due to the presence of allylic sulfur compounds such as diallyl disulfide (DADs), believed to be an anticarcinogen.[22]
In 1858, Louis Pasteur observed garlic's antibacterial activity, and it was used as an antiseptic to prevent gangrene during World War I and World War II.[23] More recently it has been found from a clinical trial that a mouthwash containing 2.5% fresh garlic shows good antimicrobial activity, although the majority of the participants reported an unpleasant taste and halitosis.[24]
In modern naturopathy, garlic is used as a treatment for intestinal worms and other intestinal parasites, both orally and as an anal suppository. Garlic cloves are used as a remedy for infections (especially chest problems), digestive disorders, and fungal infections such as thrush.
Garlic supplementation in rats along with a high protein diet has been shown to boost testosterone levels.[25]
# Properties
When crushed, Allium sativum yields allicin, a powerful antibiotic and anti-fungal compound (phytoncide). It also contains alliin, ajoene, enzymes, vitamin B, minerals, and flavonoids.
The percentage composition of the bulbs is given by E. Solly (Trans. Hon. Soc. Loud., new ser., iii. p. 60) as water 84.09%, organic matter 13.38%, and inorganic matter 1.53% - that of the leaves being water 87.14%, organic matter 11.27% and inorganic matter 1.59%.
The phytochemicals responsible for the sharp flavor of garlic are produced when the plant's cells are damaged. When a cell is broken by chopping, chewing, or crushing, enzymes stored in cell vacuoles trigger the breakdown of several sulfur-containing compounds stored in the cell fluids. The resultant compounds are responsible for the sharp or hot taste and strong smell of garlic. Some of the compounds are unstable and continue to evolve over time. Among the members of the onion family, garlic has by far the highest concentrations of initial reaction products, making garlic much more potent than onions, shallots, or leeks.[26] Although people have come to enjoy the taste of garlic, these compounds are believed to have evolved as a defensive mechanism, deterring animals like birds, insects, and worms from eating the plant.[27]
A large number of sulfur compounds contribute to the smell and taste of garlic. Diallyl disulfide is believed to be an important odour component. Allicin has been found to be the compound most responsible for the spiciness of raw garlic. This chemical opens thermoTRP (transient receptor potential) channels that are responsible for the burning sense of heat in foods. The process of cooking garlic removes allicin, thus mellowing its spiciness.[28]
When eaten in quantity, garlic may be strongly evident in the diner's sweat and breath the following day. This is because garlic's strong smelling sulfur compounds are metabolized forming allyl methyl sulfide. Allyl methyl sulfide (AMS) cannot be digested and is passed into the blood. It is carried to the lungs and the skin where it is excreted. Since digestion takes several hours, and release of AMS several hours more, the effect of eating garlic may be present for a long time.
This well-known phenomenon of "garlic breath" is alleged to be alleviated by eating fresh parsley. The herb is, therefore, included in many garlic recipes, such as Pistou and Persillade. However, since the odour results mainly from digestive processes placing compounds such as AMS in the blood, and AMS is then released through the lungs over the course of many hours, eating parsley provides only a temporary masking. One way of accelerating the release of AMS from the body is the use of a sauna. Due to its strong odor, garlic is sometimes called the "stinking rose".
Because garlic passes into the bloodstream, it can be a useful mosquito repellent. This is most likely the cause of the myth that vampires hate garlic.
# Superstition and mythology
Garlic has been regarded as a force for both good and evil. A Christian myth considers that after Satan left the Garden of Eden, garlic arose in his left footprint, and onion in the right.[29] In Europe, many cultures have used garlic for protection or white magic, perhaps owing to its reputation as a potent preventative medicine.[30] Central European folk beliefs considered garlic a powerful ward against demons, werewolves, and vampires.[30] To ward off vampires, garlic could be worn, hung in windows or rubbed on chimneys and keyholes.[31]
The association of garlic to evil spirits may be based on the antibacterial, antiparasitic value of garlic, which could prevent infections that lead to delusions, and other related mental illness symptoms.[32][33]
# Cautions
- Known adverse effects of garlic include halitosis (non-bacterial), indigestion, nausea, emesis and diarrhea.[34]
- Garlic should not be taken with warfarin, antiplatelets, saquinavir, antihypertensives, or hypoglycemic drugs.[34]
- Cases of botulism have been caused by consuming garlic-in-oil preparations. It is important to add acid when creating these mixtures and to keep them refrigerated to retard bacterial growth.[35]
- Whilst culinary quantities are considered safe during pregnancy and breastfeeding, extremely large quantities of garlic and garlic supplements have been linked with a raised risk of bleeding. Garlic may cause abortion.[34] Some breastfeeding mothers have found their babies slow to feed and have noted a garlic odour coming from their baby when they have consumed garlic.[36][34]
- The side effects of long-term garlic supplementation, if any exist, are largely unknown and no FDA-approved study has been performed. However, garlic has been consumed for several thousand years without any adverse long-term effects, suggesting that modest quantities of garlic pose, at worst, minimal risks to normal individuals.
- There have been several reports of serious burns resulting from garlic being applied topically for various purposes, including naturopathic uses and acne treatment.[37] On the basis of numerous reports of such burns, including burns to children, topical use of raw garlic, as well as insertion of raw garlic into body cavities is strongly discouraged and could lead to serious injury. In particular, topical application of raw garlic to young children is extremely risky.[38] | https://www.wikidoc.org/index.php/Garlic | |
f74895d54d0a90a850b9cac4fcebbacaf0e9db58 | wikidoc | Genome | Genome
# Overview
In biology the genome of an organism is its whole hereditary information and is encoded in the DNA (or, for some viruses, RNA). This includes both the genes and the non-coding sequences of the DNA. The term was coined in 1920 by Hans Winkler, Professor of Botany at the University of Hamburg, Germany, as a portmanteau of the words gene and chromosome.
More precisely, the genome of an organism is a complete DNA sequence of one set of chromosomes; for example, one of the two sets that a diploid individual carries in every somatic cell. The term genome can be applied specifically to mean the complete set of nuclear DNA (i.e., the "nuclear genome") but can also be applied to organelles that contain their own DNA, as with the mitochondrial genome or the chloroplast genome. When people say that the genome of a sexually reproducing species has been "sequenced," typically they are referring to a determination of the sequences of one set of autosomes and one of each type of sex chromosome, which together represent both of the possible sexes. Even in species that exist in only one sex, what is described as "a genome sequence" may be a composite from the chromosomes of various individuals. In general use, the phrase "genetic makeup" is sometimes used conversationally to mean the genome of a particular individual or organism. The study of the global properties of genomes of related organisms is usually referred to as genomics, which distinguishes it from genetics which generally studies the properties of single genes or groups of genes.
Both the number of base pairs and the number of genes vary widely from one species to another, and there is little connection between the two. At present, the highest known number of genes is around 60,000, for the protozoan causing trichomoniasis (see List of sequenced eukaryotic genomes), almost three times as many as humans have.
The Human Genome is Like a Book:
- The book is over one billion words long.
- The book is bound in 5,000 300 page volumes (the equivalent to 800 bibles long)
- The book fits into a cell nucleus the size of a pinpoint
- A copy of the book (all 5000 volumes) is contained in every cell (except red blood cells) as a strand of DNA over two miles in length.
# Types
Most biological entities more complex than a virus sometimes or always carry additional genetic material besides that which resides in their chromosomes. In some contexts, such as sequencing the genome of a pathogenic microbe, "genome" is meant to include this auxiliary material, which is carried in plasmids. In such circumstances then, "genome" describes all of the genes and non-coding DNA that have the potential to be present.
In vertebrates such as sheep and other various animals however, "genome" carries the typical connotation of only chromosomal DNA. So although human mitochondria contain genes, these genes are not considered part of the genome. In fact, mitochondria are sometimes said to have their own genome, often referred to as the "mitochondrial genome".
# Genomes and genetic variation
Note that a genome does not capture the genetic diversity or the genetic polymorphism of a species. For example, the human genome sequence in principle could be determined from just half the DNA of one cell from one individual. To learn what variations in DNA underlie particular traits or diseases requires comparisons across individuals. This point explains the common usage of "genome" (which parallels a common usage of "gene") to refer not to any particular DNA sequence, but to a whole family of sequences that share a biological context.
Although this concept may seem counter intuitive, it is the same concept that says there is no particular shape that is the shape of a cheetah. Cheetahs vary, and so do the sequences of their genomes. Yet both the individual animals and their sequences share commonalities, so one can learn something about cheetahs and "cheetah-ness" from a single example of either.
# Genome projects
The Human Genome Project was organized to map and to sequence the human genome. Other genome projects include mouse, rice, the plant Arabidopsis thaliana, the puffer fish, bacteria like E. coli, etc. In 1976, Walter Fiers at the University of Ghent (Belgium) was the first to establish the complete nucleotide sequence of a viral RNA-genome (bacteriophage MS2). The first DNA-genome project to be completed was the Phage Φ-X174, with only 5368 base pairs, which was sequenced by Fred Sanger in 1977 . The first bacterial genome to be completed was that of Haemophilus influenzae, completed by a team at The Institute for Genomic Research in 1995.
In May 2007, the New York Times announced that the full genome of DNA pioneer James D. Watson had been recorded. The article noted that some scientists believe this to be the gateway to upcoming personalized genomic medicine.
Many genomes have been sequenced by various genome projects. The cost of sequencing continues to drop.
# Comparison of different genome sizes
Note: The DNA from a single human cell has a length of ~1.8 m (but at a width of ~2.4 nanometers).
Since genomes and their organisms are very complex, one research strategy is to reduce the number of genes in a genome to the bare minimum and still have the organism in question survive. There is experimental work being done on minimal genomes for single cell organisms as well as minimal genomes for multicellular organisms (see Developmental biology). The work is both in vivo and in silico.
# Genome evolution
Genomes are more than the sum of an organism's genes and have traits that may be measured and studied without reference to the details of any particular genes and their products. Researchers compare traits such as chromosome number (karyotype), genome size, gene order, codon usage bias, and GC-content to determine what mechanisms could have produced the great variety of genomes that exist today (for recent overviews, see Brown 2002; Saccone and Pesole 2003; Benfey and Protopapas 2004; Gibson and Muse 2004; Reese 2004; Gregory 2005).
Duplications play a major role in shaping the genome. Duplications may range from extension of short tandem repeats, to duplication of a cluster of genes, and all the way to duplications of entire chromosomes or even entire genomes. Such duplications are probably fundamental to the creation of genetic novelty.
Horizontal gene transfer is invoked to explain how there is often extreme similarity between small portions of the genomes of two organisms that are otherwise very distantly related. Horizontal gene transfer seems to be common among many microbes. Also, eukaryotic cells seem to have experienced a transfer of some genetic material from their chloroplast and mitochondrial genomes to their nuclear chromosomes. | Genome
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
# Overview
In biology the genome of an organism is its whole hereditary information and is encoded in the DNA (or, for some viruses, RNA). This includes both the genes and the non-coding sequences of the DNA. The term was coined in 1920 by Hans Winkler, Professor of Botany at the University of Hamburg, Germany, as a portmanteau of the words gene and chromosome.[1]
More precisely, the genome of an organism is a complete DNA sequence of one set of chromosomes; for example, one of the two sets that a diploid individual carries in every somatic cell. The term genome can be applied specifically to mean the complete set of nuclear DNA (i.e., the "nuclear genome") but can also be applied to organelles that contain their own DNA, as with the mitochondrial genome or the chloroplast genome. When people say that the genome of a sexually reproducing species has been "sequenced," typically they are referring to a determination of the sequences of one set of autosomes and one of each type of sex chromosome, which together represent both of the possible sexes. Even in species that exist in only one sex, what is described as "a genome sequence" may be a composite from the chromosomes of various individuals. In general use, the phrase "genetic makeup" is sometimes used conversationally to mean the genome of a particular individual or organism. The study of the global properties of genomes of related organisms is usually referred to as genomics, which distinguishes it from genetics which generally studies the properties of single genes or groups of genes.
Both the number of base pairs and the number of genes vary widely from one species to another, and there is little connection between the two. At present, the highest known number of genes is around 60,000, for the protozoan causing trichomoniasis (see List of sequenced eukaryotic genomes), almost three times as many as humans have.
The Human Genome is Like a Book:
• The book is over one billion words long.
• The book is bound in 5,000 300 page volumes (the equivalent to 800 bibles long)
• The book fits into a cell nucleus the size of a pinpoint
• A copy of the book (all 5000 volumes) is contained in every cell (except red blood cells) as a strand of DNA over two miles in length.
# Types
Most biological entities more complex than a virus sometimes or always carry additional genetic material besides that which resides in their chromosomes. In some contexts, such as sequencing the genome of a pathogenic microbe, "genome" is meant to include this auxiliary material, which is carried in plasmids. In such circumstances then, "genome" describes all of the genes and non-coding DNA that have the potential to be present.
In vertebrates such as sheep and other various animals however, "genome" carries the typical connotation of only chromosomal DNA. So although human mitochondria contain genes, these genes are not considered part of the genome. In fact, mitochondria are sometimes said to have their own genome, often referred to as the "mitochondrial genome".
# Genomes and genetic variation
Note that a genome does not capture the genetic diversity or the genetic polymorphism of a species. For example, the human genome sequence in principle could be determined from just half the DNA of one cell from one individual. To learn what variations in DNA underlie particular traits or diseases requires comparisons across individuals. This point explains the common usage of "genome" (which parallels a common usage of "gene") to refer not to any particular DNA sequence, but to a whole family of sequences that share a biological context.
Although this concept may seem counter intuitive, it is the same concept that says there is no particular shape that is the shape of a cheetah. Cheetahs vary, and so do the sequences of their genomes. Yet both the individual animals and their sequences share commonalities, so one can learn something about cheetahs and "cheetah-ness" from a single example of either.
# Genome projects
The Human Genome Project was organized to map and to sequence the human genome. Other genome projects include mouse, rice, the plant Arabidopsis thaliana, the puffer fish, bacteria like E. coli, etc. In 1976, Walter Fiers at the University of Ghent (Belgium) was the first to establish the complete nucleotide sequence of a viral RNA-genome (bacteriophage MS2). The first DNA-genome project to be completed was the Phage Φ-X174, with only 5368 base pairs, which was sequenced by Fred Sanger in 1977 . The first bacterial genome to be completed was that of Haemophilus influenzae, completed by a team at The Institute for Genomic Research in 1995.
In May 2007, the New York Times announced that the full genome of DNA pioneer James D. Watson had been recorded.[2] The article noted that some scientists believe this to be the gateway to upcoming personalized genomic medicine.
Many genomes have been sequenced by various genome projects. The cost of sequencing continues to drop.
# Comparison of different genome sizes
Note: The DNA from a single human cell has a length of ~1.8 m (but at a width of ~2.4 nanometers).
Since genomes and their organisms are very complex, one research strategy is to reduce the number of genes in a genome to the bare minimum and still have the organism in question survive. There is experimental work being done on minimal genomes for single cell organisms as well as minimal genomes for multicellular organisms (see Developmental biology). The work is both in vivo and in silico.
# Genome evolution
Genomes are more than the sum of an organism's genes and have traits that may be measured and studied without reference to the details of any particular genes and their products. Researchers compare traits such as chromosome number (karyotype), genome size, gene order, codon usage bias, and GC-content to determine what mechanisms could have produced the great variety of genomes that exist today (for recent overviews, see Brown 2002; Saccone and Pesole 2003; Benfey and Protopapas 2004; Gibson and Muse 2004; Reese 2004; Gregory 2005).
Duplications play a major role in shaping the genome. Duplications may range from extension of short tandem repeats, to duplication of a cluster of genes, and all the way to duplications of entire chromosomes or even entire genomes. Such duplications are probably fundamental to the creation of genetic novelty.
Horizontal gene transfer is invoked to explain how there is often extreme similarity between small portions of the genomes of two organisms that are otherwise very distantly related. Horizontal gene transfer seems to be common among many microbes. Also, eukaryotic cells seem to have experienced a transfer of some genetic material from their chloroplast and mitochondrial genomes to their nuclear chromosomes. | https://www.wikidoc.org/index.php/Genome | |
acce64c1c3f36222127de6c68915b0a909831dcf | wikidoc | Germ-X | Germ-X
Germ-X® is the brand name of a line of antibacterial and antimicrobial products marketed in the United States. Germ-X products include instant hand sanitizer gels, foaming hand soap, and soft wipes. Germ-X products are manufactured by Vi-Jon Laboratories, based in St. Louis, Missouri.
The active ingredient in Germ-X hand sanitizer is ethyl alcohol. The active ingredient in Germ-X hand soap and soft wipes is benzalkonium chloride. The brand's advertising slogan is "Kills 99.99% of germs".
Vi-Jon cites the Food and Drug Administration's (FDA) October 20, 2005 Non-Prescription Drugs Advisory Committee Meeting as proof of Germ-X's effectiveness.
# Scents
There are various scents for Germ-X hand sanitizer, one of which is "lavender & chamomile". It comes in a clear bottle with a purple pump. The sanitizer itself takes on a purple hue. | Germ-X
Germ-X® is the brand name of a line of antibacterial and antimicrobial products marketed in the United States. Germ-X products include instant hand sanitizer gels, foaming hand soap, and soft wipes. Germ-X products are manufactured by Vi-Jon Laboratories, based in St. Louis, Missouri.
The active ingredient in Germ-X hand sanitizer is ethyl alcohol. The active ingredient in Germ-X hand soap and soft wipes is benzalkonium chloride. The brand's advertising slogan is "Kills 99.99% of germs".
Vi-Jon cites the Food and Drug Administration's (FDA) October 20, 2005 Non-Prescription Drugs Advisory Committee Meeting as proof of Germ-X's effectiveness.[1][2]
# Scents
There are various scents for Germ-X hand sanitizer, one of which is "lavender & chamomile". It comes in a clear bottle with a purple pump. The sanitizer itself takes on a purple hue. | https://www.wikidoc.org/index.php/Germ-X | |
4283ca80e072f745e0131d877d4b9e1ce36814f8 | wikidoc | Geyser | Geyser
A geyser is a hot spring characterized by intermittent discharge of water ejected turbulently and accomplished by a vapor phase. The name geyser comes from Geysir, the name of an erupting spring at Haukadalur, Iceland; that name, in turn, comes from the Icelandic verb gjósa, “to gush”.
The formation of geysers requires a favourable hydrogeology which exists in only a few places on Earth, and so they are fairly rare phenomena. There must be a volcanic heat source. Generally all geyser field sites are located near active volcanic areas. The surface water works its way down to an average depth of around Template:Dist m ft where it meets up with the hot rocks. About 1,000 exist worldwide, with about half of these in Yellowstone National Park, U.S. A geyser's eruptive activity may change or cease due to ongoing mineral deposition within the geyser plumbing, exchange of functions with nearby hot springs, earthquake influences, and human intervention.
Erupting fountains of liquefied nitrogen have been observed on Neptune's moon Triton, as have possible signs of carbon dioxide eruptions from Mars' south polar ice cap. These phenomena are also often referred to as geysers. Instead of being driven by geothermal energy, they seem to rely on solar heating aided by a kind of solid-state greenhouse effect. On Triton, the nitrogen may erupt to heights of 8 kilometres (5 mi).
# Formation and working
Geysers are temporary geological features. The life span of a geyser is, at the most, only a few thousand years. Geysers are generally associated with volcanic areas. Geysers are caused when underground chambers of water are heated to the boiling point by the volcanic rock. When heat causes the water to boil, pressure forces a superheated column of steam and water to the surface. Their formation specifically requires the combination of 3 geologic conditions that are usually found in volcanic terrain.
- Intense heat- The heat needed for geyser formation comes from magma when it is near the surface of the earth.The fact that they need heat much higher than normally found near the earth's surface is the reason they are associated with volcanoes or volcanic areas. Geysers, though rare, are found in the same geologic settings where volcanic heat sources are available.
- Water- The water a geyser ejects comes from snow and rain. When precipitation reaches the ground, most of it drains into rivers and streams. A small portion, perhaps 5% gets, soaked into the ground. Moving gradually through tiny cracks it finds its way into the underground tunnels that make up the plumbing of a geyser, then is shot to the surface during an eruption. Travel from the surface down through the rock and out through a geyser eruption can take up-to a time period of 500 years.
- A plumbing system- In order for the heated water to form a geyser a plumbing system is required. This includes a reservoir to hold the water while it is being heated. Geysers are generally aligned along faults, the cracks in the earth formed by earthquakes. The plumbing system is made up of a system of fractures, fissures, porous spaces and sometimes cavities. Constrictions in the system are essential to the building up of pressure before an eruption.
Ultimately, the temperatures near the bottom of the geyser rise to a point where boiling begins; steam bubbles rise to the top of the column. As they burst through the geyser's vent, some water overflows or splashes out, reducing the weight of the column and thus the pressure on the water underneath. With this release of pressure, the superheated water flashes into steam, boiling violently throughout the column. The resulting froth of expanding steam and hot water then sprays out of the geyser hole.
# Eruptions
Geyser activity, like all hot spring activity, is caused by surface water gradually seeping down through the ground until it meets rock heated by magma. The geothermally heated water then rises back toward the surface by convection through porous and fractured rocks. Geysers differ from non-eruptive hot springs in their subterranean structure; many consist of a small vent at the surface connected to one or more narrow tubes that lead to underground reservoirs of water.
As the geyser fills, the water at the top of the column cools off, but because of the narrowness of the channel, convective cooling of the water in the reservoir is impossible. The cooler water above presses down on the hotter water beneath, not unlike the lid of a pressure cooker, allowing the water in the reservoir to become superheated, i.e. to remain liquid at temperatures well above the boiling point.
The rocks in the nearby region produce a material called geyserite. Geyserite is mostly silicon dioxide (SiO2), is dissolved from the rocks and gets deposited on the walls of the geyser's plumbing system and on the surface. The deposits make the channels carrying the water up to the surface pressure-tight. This allows the pressure to be carried all the way to the top and not be leaked out into the loose gravel or soil that are normally under the geyser fields.
Eventually the water remaining in the geyser cools back to below the boiling point and the eruption ends; heated groundwater begins seeping back into the reservoir, and the whole cycle begins again. The duration of eruptions and time between successive eruptions vary greatly from geyser to geyser; Strokkur in Iceland erupts for a few seconds every few minutes, while Grand Geyser in the U.S. erupts for up to 10 minutes every 8–12 hours.
# General categorization
There are two types of geysers: fountain geysers which erupt from pools of water, typically in a series of intense, even violent, bursts; and cone geysers which erupt from cones or mounds of siliceous sinter (also known as geyserite), usually in steady jets that last anywhere from a few seconds to several minutes. Old Faithful, perhaps the best-known geyser at Yellowstone National Park, is an example of a cone geyser. Grand Geyser, the tallest predictable geyser on earth, also at Yellowstone National Park, is an example of a fountain geyser.
The intense transient forces inside erupting geysers are the main reason for their rarity. There are many volcanic areas in the world that have hot springs, mud pots and fumaroles, but very few with geysers. This is because in most places, even where other necessary conditions for geyser activity exist, the rock structure is loose, and eruptions will erode the channels and rapidly destroy any nascent geysers.
Most geysers form in places where there is volcanic rhyolite rock which dissolves in hot water and forms mineral deposits called siliceous sinter, or geyserite, along the inside of the plumbing systems. Over time these deposits cement the rock together tightly, strengthening the channel walls and enabling the geyser to persist; as mentioned in the previous section.
Geysers are fragile phenomena and if conditions change, they can ‘die’. Many geysers have been destroyed by people throwing litter and debris into them; others have ceased to erupt due to dewatering by geothermal power plants. The Great Geysir of Iceland has had periods of activity and dormancy. During its long dormant periods, eruptions were sometimes humanly-induced—often on special occasions—by the addition of surfactants to the water. Inducing eruptions at Geysir is no longer done, as the forced eruptions were damaging the geyser's special plumbing system. Following an earthquake in Iceland in 2000 the geyser became somewhat more active again. Initially the geyser erupted about eight times a day. As of July 2003, Geysir erupts several times a week.
# Biology of geysers
The specific colours of geysers derive from the fact that despite the apparently harsh conditions, life is often found in them (and also in other hot habitats) in the form of thermophilic prokaryotes. No known eukaryote can survive over 60 °C (140 °F).
In the 1960s, when the research of biology of geysers first appeared, scientists were generally convinced that no life can survive above around 73 (163 )—the upper limit for the survival of cyanobacteria, as the structure of key cellular proteins and deoxyribonucleic acid (DNA) would be destroyed. The optimal temperature for thermophilic bacteria was placed even lower, around 55 (131 ).
However, the observations proved that it is actually possible for life to exist at high temperatures and that some bacteria prefer even temperatures higher than boiling point of water. Dozens of such bacteria are known nowadays.
Thermophiles prefer temperatures from 50 (122 ) to 70 (158 ) whilst hyperthermophiles grow better at temperatures as high as 80 (176 ) to 110 (230 ). As they have heat-stable enzymes that retain their activity even at high temperatures, they have been used as a source of thermostable tools, that are important in medicine and biotechnology, for example in manufacturing antibiotics, plastics, detergents (by the use of heat-stable enzymes lipases, pullulanases and proteases), and fermentation products (for example ethanol is produced). The fact that such bacteria exist also stretches our imagination about life on other celestial bodies, both inside and outside of solar system. Among these, the first discovered and the most important for biotechnology is Thermus aquaticus.
# Major geyser fields and their distribution
Geysers are quite rare, requiring a combination of water, heat, and fortuitous plumbing. The combination exists in few places on Earth.
## Yellowstone National Park
Yellowstone is the largest geyser locale, containing thousands of hot springs, and approximately 300 to 500 geysers. It is home to half of the world's total number of geysers in its nine geyser basins. It is located in Wyoming, United States. Yellowstone includes the tallest active geyser (Steamboat Geyser in Norris Geyser Basin), as well as the renowned Old Faithful Geyser, Beehive Geyser, Giantess Geyser, Lion Geyser, Plume Geyser, Aurum Geyser, Castle Geyser, Sawmill Geyser, Grand Geyser, Oblong Geyser, Giant Geyser, Daisy Geyser, Grotto Geyser, Fan & Mortar Geysers, & Riverside Geyser, all in the Upper Geyser Basin which alone contains nearly 180 geysers.
## Dolina Geiserov
Dolina Geiserov is one of the geysers in the Valley of Geysers in the Kamchatka Peninsula of Russia. The area was discovered and explored by T.I. Ustinova in 1941. Approximately 200 geysers exist in the area along with many hot-water springs and perpetual spouters. The area was formed due to vigorous volcanic activity. The peculiar way of eruptions are an important feature of these geysers. Most of the geysers erupt at angles, and only very few have the geyser cones that exist at many other of the world's geyser fields. On June 3 2007 a massive mudflow influenced two thirds of the valley. It was then reported that a thermal lake was forming above the valley. Few days later, waters were observed to have receded somewhat, exposing some of the submerged features. Velikan Geyser, one of the field's largest, was not buried in the slide and has recently been observed to be active.
## El Tatio
The name "El Tatio" roughly translates as "the grandfather". El Tatio is located in the high valleys on the Andes surrounded by many active Volcanoes in Chile, South America at around 4,200 meters above mean sea level. The valley is home to approximately 80 geysers at present. It became the largest geyser field in the Southern Hemisphere after the destruction of many of the New Zealand geysers, and is the third largest geyser field in the world. The salient feature of these geysers is that the height of their eruptions is very low, tallest being only six meters high. The average geyser eruption height at El Tatio is about Template:Dist m ft
## Taupo Volcanic Zone
The Taupo Volcanic Zone is located on the North Island in New Zealand. It is 350 kilometres (217 mi) long by 50 kilometres (31 mi) wide and lies over a subduction zone in the earth's crust. Mount Ruapehu marks its southwestern end, while the submarine Whakatane volcano (85 kilometres beyond White Island) is considered its northeastern limit. Many geysers in this zone were destroyed due to Geothermal developments and a hydroelectric reservoir, but several dozen geysers still exist. In the beginning of the twentieth century, the largest geyser ever known, the Waimangu Geyser existed in this zone. It began erupting in 1900 and erupted periodically for four years until a landslide changed the local water table. Eruptions of Waimangu would typically reach Template:Dist m ft and some superbursts are known to have reached Template:Dist m ft. Recent scientific work indicates that the earth's crust below the zone may be as little as 5 kilometres (3 mi) thick. Beneath this lies a film of magma 50 kilometres (31 mi) wide and 160 kilometres (99 mi) long.
## Iceland
Iceland is an island country off the western coast of Europe in the Atlantic Ocean. Geysers and hot springs are distributed all over the island. The geyser, or the local name geysir are located in Haukadalur. Geysers are known to have existed in at least a dozen other areas on the island. The "Great Geysir", which first erupted in the 14th century, gave rise to the word "geyser". It used to erupt every 60 minutes until the early 1900s when it became dormant. Earthquakes in June 2000 subsequently reawakened the giant and it now erupts approximately every 8 to 10 hours and may reach up to Template:Dist m ft.
## Extinct/Dormant geyser fields
There used to be two large geysers fields in Nevada—Beowawe and Steamboat Springs—but they were destroyed by the installation of nearby geothermal power plants. At the plants, geothermal drilling reduced the available heat and lowered the local water table to the point that geyser activity could no longer be sustained.
Many of New Zealand’s geysers have been destroyed by humans in the last century. Several New Zealand geysers have also become dormant or extinct by natural means. The main remaining field is Whakarewarewa at Rotorua. Two thirds of the geysers at Orakei Korako were flooded by the Ohakuri hydroelectric dam in 1961. The Wairakei field was lost to a geothermal power plant in 1958. The Taupo Spa field was lost when the Waikato River level was deliberately altered in the 1950s. The Rotomahana field was destroyed by the Mount Tarawera eruption in 1886.
# Misnamed geysers
There are various other types of geysers which are different in nature compared to the normal steam-driven geysers. These geysers not only differ in their style of eruption but also in the cause that makes them erupt. Such geysers are not true geysers but are yet referred as one as they all emit water under pressure.
In a number of places where there is geothermal activity, wells have been drilled and fitted with impermeable casements that allow them to erupt like geysers. Even though the vents of such geysers are artificial, it is tapped into a natural hydrothermal system. Though these are so-called artificial geysers, technically known as erupting geothermal wells, are not true geysers. Little Old Faithful Geyser, in Calistoga, California, is probably an example of it. The geyser erupts from the casing of the a well drilled in the late 1800s. According to Dr. John Rinehart in his book A Guide to Geyser Gazing (1976 p.49), a man had drilled into the geyser in search for water. He had actually "simply opened up a dead geyser".
Cold-water geysers' eruption is similar to their hot water counterparts, except that CO2 bubbles drive the eruption instead of steam. In cold-water geysers, CO2-laden water lies in a confined aquifer, in which water and CO2 are trapped by less permeable overlying strata. This water and CO2 can escape this strata only weak regions like faults, joints, or drilled wells. A drilled borehole provides an escape for the pressurized water and CO2 to reach the surface. The magnitude and frequency of such eruptions depend on various factors such as plumbing depth, CO2 concentrations, aquifer yield etc. The column of water exerts enough pressure on the gaseous CO2 so that it remains in the water in small bubbles. When the pressure decreases due to formation of a fissure, the CO2 bubbles expand. This expansion dispaces the water and causes the eruption.The appearance of cold-water geysers may be quite similar to their steam-driven counterparts; however, often CO2-laden water is more white and frothy. The best known of these is probably Crystal Geyser, near Green River, Utah.. There are also two cold-water geysers in Germany: Brubbel and Geysir Andernach.
A perpetual spouter is a natural hot spring that spouts water constantly without stopping for recharge. Some of these are incorrectly called geysers, but because they are not periodic in nature they are not considered true geysers.
# Commercial uses of geysers
Geysers are used for various activities such as electricity generation, heating and tourism. Many geothermal reserves are found all around the world. Geysers in Iceland are one of the most commercially viable geyser location in the world. Since 1920's hot water directed from the geysers have been used to heat greenhouses and used to grow food that could not have been cultivated in Iceland's inhospitable climate. Steam and hot water from the geysers has also been used for heating homes since 1943 in Iceland. In 1979
the U.S. Department of Energy (DOE) actively promoted development of geothermal energy in the Geysers-Calistoga Known Geothermal Resource Area (KGRA) through a variety of research programs and the Geothermal Loan Guarantee Program and was thus obligated by law to assess its potential environmental impacts.
# Nitrogen geysers on Triton
One of the great surprises of the Voyager 2 flyby of Neptune in 1989 was the discovery of geysers on its moon, Triton. Astronomers noticed dark plumes rising to some 8 km above the surface,and depositing material up to 150 km downstream.,
All the geysers observed were located between 50° and 57°S, the part of Triton's surface close to the subsolar point. This indicates that solar heating, although very weak at Triton's great distance from the Sun, probably plays a crucial role. It is thought that the surface of Triton probably consists of a semi-transparent layer of frozen nitrogen white in colour, which creates a kind of greenhouse effect, heating the frozen material beneath it until it breaks the surface in an eruption. A temperature increase of just 4 K above the ambient surface temperature of 37 K could drive eruptions to the heights observed. But more likely these eruptions are caused by tidal forces.
Geothermal energy may also be important. Unusually for a major satellite, Triton orbits Neptune in a retrograde orbit—that is, in the opposite direction to Neptune's rotation. This generates tidal forces which are causing Triton's orbit to decay, so that in several billion years time it will reach its Roche limit with Neptune. The tidal forces may also generate heat inside Triton, in the same way as Jupiter's gravity generates tidal forces on Io which drive its extreme volcanic activity.
Each eruption of a Triton geyser may last up to a year, and during this time about 0.1 ] (Expression error: Missing operand for *. ]) of material may be deposited downwind. Voyager's images of Triton's southern hemisphere show many streaks of dark material laid down by geyser activity.
# Notes
- ↑ Bryan, T.S. 1995
- ↑ Jump up to: 2.0 2.1 2.2 2.3 How geysers form Gregory L. Jones; wyojones.com Retrieved on 2008-04-05
- ↑ Jump up to: 3.0 3.1 3.2 3.3 3.4 Lee Krystek Weird Geology: Geysers unmuseum.org Retrieved on 2008-03-28
- ↑ Yellowstone thermal features Yahoo! Inc. Retrieved on 2008-04-02
- ↑ Jump up to: 5.0 5.1 5.2 Plumbing system Advameg Inc. Retrieved on 2008-04-02
- ↑ Jump up to: 6.0 6.1 Lethe E. Morrison, Fred W. Tanner; Studies on Thermophilic Bacteria
Botanical Gazette, Vol. 77, No. 2 (Apr., 1924), pp. 171-185
- ↑ Michael T. Madigan and Barry L. Marrs; Extremophiles atropos.as.arizona.edu Retrieved on 2008-04-01
- ↑ Vielle, C.; Zeikus, G.J. Hyperthermophilic Enzymes: Sources, Uses, and Molecular Mechanisms for Thermostability. Microbiology and Molecular Biology Reviews. 2001, 65(1), 1-34.
- ↑ Industrial Uses of Thermophilic Cellulase University of Delaware, Retrieved on 2008-03-29
- ↑ Glennon, J.A. and Pfaff R.M. 2003; Bryan 1995
- ↑ Jump up to: 11.0 11.1 11.2 11.3 11.4 11.5 11.6 Glennon, J Allan"World Geyser Fields" Retrieved on 2008-04-04
- ↑ "Yellowstone geysers" nps.gov Retrieved on 2008-03-20
- ↑ Mehta, Aalok (2008-04-16). "Photo in the News: Russia's Valley of the Geysers Lost in Landslide". National Geographic. Retrieved 2007-06-07..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
- ↑ Harding, Luke (2007-06-05). "Mudslide fully changes terrain in Kamchatka's Valley of Geysers". Guardian Unlimited. Retrieved 2008-04-16.
- ↑ Shpilenok, Igor. "June 2007 Special release - The Natural Disaster at the Valley of the Geysers". Retrieved 2008-04-16. Text "date-2007-06-09" ignored (help)
- ↑ Glennon, J.A. and Pfaff. R.M., 2003)
- ↑ Gamble, J. A., I. C. Wright and J. A. Baker (1993). "Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand" New Zealand Journal of Geology and Geophysics, 36, 417-435.
- ↑ Central North Island sitting on magma film Paul Easton, The Dominion Post, 15 September 2007. Retrieved 2008-04-16
- ↑ Gardner Servian, Solveig"Geysers of Iceland" Retrieved on 2008-04-16
- ↑ "Whakarewarewa, The Thermal Village" Retrieved 2008-04-04
- ↑ Jones, Wyoming "Old Faithful Geyser of California" WyoJones' Geyser Pages Retrieved on 2008-03-31
- ↑ Glennon, J. Alan"Carbon-Dioxide-Driven, Cold-Water Geysers" Retrieved on 2008-04-01
- ↑ Glennon, J.A. 2005; Glennon, J.A. and Pfaff, R.M. 2005
- ↑ WyoJones"Thermal Feature Definitions" WyoJones Retrieved on 2008-04-03
- ↑ Geysers and Energy american.edu Retrieved on 2008-04-12
- ↑ Kerry O’Banion and Charles Hall Geothermal energy and the land resource: conflicts and constraints in The Geysers- Calistoga KGRA osti.gov Retrieved on 2008-04-12
- ↑ "Triton (Voyager)". NASA (Voyager The Interstellar Mission). June 1, 2005. Retrieved 2008-04-03. Check date values in: |date= (help)
- ↑ Jump up to: 28.0 28.1 28.2 Kirk, R.L., Branch of Astrogeology"Thermal Models of Insolation-driven Nitrogen Geysers on Triton" Harvard Retrieved 2008-04-08
- ↑ "Roche Limit"Harvard Retrieved 2008-04-08 | Geyser
A geyser is a hot spring characterized by intermittent discharge of water ejected turbulently and accomplished by a vapor phase. The name geyser comes from Geysir, the name of an erupting spring at Haukadalur, Iceland; that name, in turn, comes from the Icelandic verb gjósa, “to gush”.
The formation of geysers requires a favourable hydrogeology which exists in only a few places on Earth, and so they are fairly rare phenomena. There must be a volcanic heat source. Generally all geyser field sites are located near active volcanic areas. The surface water works its way down to an average depth of around Template:Dist m ft where it meets up with the hot rocks. About 1,000 exist worldwide, with about half of these in Yellowstone National Park, U.S. A geyser's eruptive activity may change or cease due to ongoing mineral deposition within the geyser plumbing, exchange of functions with nearby hot springs, earthquake influences, and human intervention.[1]
Erupting fountains of liquefied nitrogen have been observed on Neptune's moon Triton, as have possible signs of carbon dioxide eruptions from Mars' south polar ice cap. These phenomena are also often referred to as geysers. Instead of being driven by geothermal energy, they seem to rely on solar heating aided by a kind of solid-state greenhouse effect. On Triton, the nitrogen may erupt to heights of 8 kilometres (5 mi).
# Formation and working
Geysers are temporary geological features. The life span of a geyser is, at the most, only a few thousand years. Geysers are generally associated with volcanic areas.[2] Geysers are caused when underground chambers of water are heated to the boiling point by the volcanic rock. When heat causes the water to boil, pressure forces a superheated column of steam and water to the surface. Their formation specifically requires the combination of 3 geologic conditions that are usually found in volcanic terrain.[2]
- Intense heat- The heat needed for geyser formation comes from magma when it is near the surface of the earth.The fact that they need heat much higher than normally found near the earth's surface is the reason they are associated with volcanoes or volcanic areas. Geysers, though rare, are found in the same geologic settings where volcanic heat sources are available.
- Water- The water a geyser ejects comes from snow and rain. When precipitation reaches the ground, most of it drains into rivers and streams. A small portion, perhaps 5% gets, soaked into the ground. Moving gradually through tiny cracks it finds its way into the underground tunnels that make up the plumbing of a geyser, then is shot to the surface during an eruption. Travel from the surface down through the rock and out through a geyser eruption can take up-to a time period of 500 years.[3]
- A plumbing system- In order for the heated water to form a geyser a plumbing system is required. This includes a reservoir to hold the water while it is being heated. Geysers are generally aligned along faults, the cracks in the earth formed by earthquakes.[2] The plumbing system is made up of a system of fractures, fissures, porous spaces and sometimes cavities. Constrictions in the system are essential to the building up of pressure before an eruption.
Ultimately, the temperatures near the bottom of the geyser rise to a point where boiling begins; steam bubbles rise to the top of the column. As they burst through the geyser's vent, some water overflows or splashes out, reducing the weight of the column and thus the pressure on the water underneath. With this release of pressure, the superheated water flashes into steam, boiling violently throughout the column. The resulting froth of expanding steam and hot water then sprays out of the geyser hole.[2]
# Eruptions
Geyser activity, like all hot spring activity, is caused by surface water gradually seeping down through the ground until it meets rock heated by magma. The geothermally heated water then rises back toward the surface by convection through porous and fractured rocks. Geysers differ from non-eruptive hot springs in their subterranean structure; many consist of a small vent at the surface connected to one or more narrow tubes that lead to underground reservoirs of water.[3]
As the geyser fills, the water at the top of the column cools off, but because of the narrowness of the channel, convective cooling of the water in the reservoir is impossible. The cooler water above presses down on the hotter water beneath, not unlike the lid of a pressure cooker, allowing the water in the reservoir to become superheated, i.e. to remain liquid at temperatures well above the boiling point.[3]
The rocks in the nearby region produce a material called geyserite. Geyserite is mostly silicon dioxide (SiO2), is dissolved from the rocks and gets deposited on the walls of the geyser's plumbing system and on the surface. The deposits make the channels carrying the water up to the surface pressure-tight. This allows the pressure to be carried all the way to the top and not be leaked out into the loose gravel or soil that are normally under the geyser fields.[3]
Eventually the water remaining in the geyser cools back to below the boiling point and the eruption ends; heated groundwater begins seeping back into the reservoir, and the whole cycle begins again. The duration of eruptions and time between successive eruptions vary greatly from geyser to geyser; Strokkur in Iceland erupts for a few seconds every few minutes, while Grand Geyser in the U.S. erupts for up to 10 minutes every 8–12 hours.[3]
# General categorization
There are two types of geysers: fountain geysers which erupt from pools of water, typically in a series of intense, even violent, bursts; and cone geysers which erupt from cones or mounds of siliceous sinter (also known as geyserite), usually in steady jets that last anywhere from a few seconds to several minutes. Old Faithful, perhaps the best-known geyser at Yellowstone National Park, is an example of a cone geyser. Grand Geyser, the tallest predictable geyser on earth, also at Yellowstone National Park, is an example of a fountain geyser.[4]
The intense transient forces inside erupting geysers are the main reason for their rarity. There are many volcanic areas in the world that have hot springs, mud pots and fumaroles, but very few with geysers. This is because in most places, even where other necessary conditions for geyser activity exist, the rock structure is loose, and eruptions will erode the channels and rapidly destroy any nascent geysers.[5]
Most geysers form in places where there is volcanic rhyolite rock which dissolves in hot water and forms mineral deposits called siliceous sinter, or geyserite, along the inside of the plumbing systems. Over time these deposits cement the rock together tightly, strengthening the channel walls and enabling the geyser to persist; as mentioned in the previous section.[5]
Geysers are fragile phenomena and if conditions change, they can ‘die’. Many geysers have been destroyed by people throwing litter and debris into them; others have ceased to erupt due to dewatering by geothermal power plants. The Great Geysir of Iceland has had periods of activity and dormancy. During its long dormant periods, eruptions were sometimes humanly-induced—often on special occasions—by the addition of surfactants to the water. Inducing eruptions at Geysir is no longer done, as the forced eruptions were damaging the geyser's special plumbing system. Following an earthquake in Iceland in 2000 the geyser became somewhat more active again. Initially the geyser erupted about eight times a day. As of July 2003, Geysir erupts several times a week.[5]
# Biology of geysers
The specific colours of geysers derive from the fact that despite the apparently harsh conditions, life is often found in them (and also in other hot habitats) in the form of thermophilic prokaryotes. No known eukaryote can survive over 60 °C (140 °F).[6]
In the 1960s, when the research of biology of geysers first appeared, scientists were generally convinced that no life can survive above around 73 (163 )—the upper limit for the survival of cyanobacteria, as the structure of key cellular proteins and deoxyribonucleic acid (DNA) would be destroyed. The optimal temperature for thermophilic bacteria was placed even lower, around 55 (131 ).[6]
However, the observations proved that it is actually possible for life to exist at high temperatures and that some bacteria prefer even temperatures higher than boiling point of water. Dozens of such bacteria are known nowadays.[7]
Thermophiles prefer temperatures from 50 (122 ) to 70 (158 ) whilst hyperthermophiles grow better at temperatures as high as 80 (176 ) to 110 (230 ). As they have heat-stable enzymes that retain their activity even at high temperatures, they have been used as a source of thermostable tools, that are important in medicine and biotechnology,[8] for example in manufacturing antibiotics, plastics, detergents (by the use of heat-stable enzymes lipases, pullulanases and proteases), and fermentation products (for example ethanol is produced). The fact that such bacteria exist also stretches our imagination about life on other celestial bodies, both inside and outside of solar system. Among these, the first discovered and the most important for biotechnology is Thermus aquaticus.[9]
# Major geyser fields and their distribution
Geysers are quite rare, requiring a combination of water, heat, and fortuitous plumbing. The combination exists in few places on Earth.[10][11]
## Yellowstone National Park
Yellowstone is the largest geyser locale, containing thousands of hot springs, and approximately 300 to 500 geysers. It is home to half of the world's total number of geysers in its nine geyser basins. It is located in Wyoming, United States.[12] Yellowstone includes the tallest active geyser (Steamboat Geyser in Norris Geyser Basin), as well as the renowned Old Faithful Geyser, Beehive Geyser, Giantess Geyser, Lion Geyser, Plume Geyser, Aurum Geyser, Castle Geyser, Sawmill Geyser, Grand Geyser, Oblong Geyser, Giant Geyser, Daisy Geyser, Grotto Geyser, Fan & Mortar Geysers, & Riverside Geyser, all in the Upper Geyser Basin which alone contains nearly 180 geysers.[11]
## Dolina Geiserov
Dolina Geiserov is one of the geysers in the Valley of Geysers in the Kamchatka Peninsula of Russia. The area was discovered and explored by T.I. Ustinova in 1941. Approximately 200 geysers exist in the area along with many hot-water springs and perpetual spouters. The area was formed due to vigorous volcanic activity. The peculiar way of eruptions are an important feature of these geysers. Most of the geysers erupt at angles, and only very few have the geyser cones that exist at many other of the world's geyser fields.[11] On June 3 2007 a massive mudflow influenced two thirds of the valley.[13] It was then reported that a thermal lake was forming above the valley.[14] Few days later, waters were observed to have receded somewhat, exposing some of the submerged features. Velikan Geyser, one of the field's largest, was not buried in the slide and has recently been observed to be active.[15]
## El Tatio
The name "El Tatio" roughly translates as "the grandfather". El Tatio is located in the high valleys on the Andes surrounded by many active Volcanoes in Chile, South America at around 4,200 meters above mean sea level. The valley is home to approximately 80 geysers at present. It became the largest geyser field in the Southern Hemisphere after the destruction of many of the New Zealand geysers, and is the third largest geyser field in the world. The salient feature of these geysers is that the height of their eruptions is very low, tallest being only six meters high. The average geyser eruption height at El Tatio is about Template:Dist m ft[11][16]
## Taupo Volcanic Zone
The Taupo Volcanic Zone is located on the North Island in New Zealand. It is 350 kilometres (217 mi) long by 50 kilometres (31 mi) wide and lies over a subduction zone in the earth's crust. Mount Ruapehu marks its southwestern end, while the submarine Whakatane volcano (85 kilometres beyond White Island) is considered its northeastern limit.[17] Many geysers in this zone were destroyed due to Geothermal developments and a hydroelectric reservoir, but several dozen geysers still exist. In the beginning of the twentieth century, the largest geyser ever known, the Waimangu Geyser existed in this zone. It began erupting in 1900 and erupted periodically for four years until a landslide changed the local water table. Eruptions of Waimangu would typically reach Template:Dist m ft and some superbursts are known to have reached Template:Dist m ft.[11] Recent scientific work indicates that the earth's crust below the zone may be as little as 5 kilometres (3 mi) thick. Beneath this lies a film of magma 50 kilometres (31 mi) wide and 160 kilometres (99 mi) long.[18]
## Iceland
Iceland is an island country off the western coast of Europe in the Atlantic Ocean. Geysers and hot springs are distributed all over the island. The geyser, or the local name geysir are located in Haukadalur. Geysers are known to have existed in at least a dozen other areas on the island. The "Great Geysir", which first erupted in the 14th century, gave rise to the word "geyser". It used to erupt every 60 minutes until the early 1900s when it became dormant. Earthquakes in June 2000 subsequently reawakened the giant and it now erupts approximately every 8 to 10 hours and may reach up to Template:Dist m ft.[11][19]
## Extinct/Dormant geyser fields
There used to be two large geysers fields in Nevada—Beowawe and Steamboat Springs—but they were destroyed by the installation of nearby geothermal power plants. At the plants, geothermal drilling reduced the available heat and lowered the local water table to the point that geyser activity could no longer be sustained.[11]
Many of New Zealand’s geysers have been destroyed by humans in the last century. Several New Zealand geysers have also become dormant or extinct by natural means. The main remaining field is Whakarewarewa at Rotorua.[20] Two thirds of the geysers at Orakei Korako were flooded by the Ohakuri hydroelectric dam in 1961. The Wairakei field was lost to a geothermal power plant in 1958. The Taupo Spa field was lost when the Waikato River level was deliberately altered in the 1950s. The Rotomahana field was destroyed by the Mount Tarawera eruption in 1886.
# Misnamed geysers
There are various other types of geysers which are different in nature compared to the normal steam-driven geysers. These geysers not only differ in their style of eruption but also in the cause that makes them erupt. Such geysers are not true geysers but are yet referred as one as they all emit water under pressure.
In a number of places where there is geothermal activity, wells have been drilled and fitted with impermeable casements that allow them to erupt like geysers. Even though the vents of such geysers are artificial, it is tapped into a natural hydrothermal system. Though these are so-called artificial geysers, technically known as erupting geothermal wells, are not true geysers. Little Old Faithful Geyser, in Calistoga, California, is probably an example of it. The geyser erupts from the casing of the a well drilled in the late 1800s. According to Dr. John Rinehart in his book A Guide to Geyser Gazing (1976 p.49), a man had drilled into the geyser in search for water. He had actually "simply opened up a dead geyser".[21]
Cold-water geysers' eruption is similar to their hot water counterparts, except that CO2 bubbles drive the eruption instead of steam. In cold-water geysers, CO2-laden water lies in a confined aquifer, in which water and CO2 are trapped by less permeable overlying strata. This water and CO2 can escape this strata only weak regions like faults, joints, or drilled wells. A drilled borehole provides an escape for the pressurized water and CO2 to reach the surface. The magnitude and frequency of such eruptions depend on various factors such as plumbing depth, CO2 concentrations, aquifer yield etc. The column of water exerts enough pressure on the gaseous CO2 so that it remains in the water in small bubbles. When the pressure decreases due to formation of a fissure, the CO2 bubbles expand. This expansion dispaces the water and causes the eruption.The appearance of cold-water geysers may be quite similar to their steam-driven counterparts; however, often CO2-laden water is more white and frothy.[22] The best known of these is probably Crystal Geyser, near Green River, Utah..[23] There are also two cold-water geysers in Germany: Brubbel and Geysir Andernach.
A perpetual spouter is a natural hot spring that spouts water constantly without stopping for recharge. Some of these are incorrectly called geysers, but because they are not periodic in nature they are not considered true geysers.[24]
# Commercial uses of geysers
Geysers are used for various activities such as electricity generation, heating and tourism. Many geothermal reserves are found all around the world. Geysers in Iceland are one of the most commercially viable geyser location in the world. Since 1920's hot water directed from the geysers have been used to heat greenhouses and used to grow food that could not have been cultivated in Iceland's inhospitable climate.[25] Steam and hot water from the geysers has also been used for heating homes since 1943 in Iceland. In 1979
the U.S. Department of Energy (DOE) actively promoted development of geothermal energy in the Geysers-Calistoga Known Geothermal Resource Area (KGRA) through a variety of research programs and the Geothermal Loan Guarantee Program and was thus obligated by law to assess its potential environmental impacts.[26]
# Nitrogen geysers on Triton
One of the great surprises of the Voyager 2 flyby of Neptune in 1989 was the discovery of geysers on its moon, Triton. Astronomers noticed dark plumes rising to some 8 km above the surface,and depositing material up to 150 km downstream.,[27]
All the geysers observed were located between 50° and 57°S, the part of Triton's surface close to the subsolar point. This indicates that solar heating, although very weak at Triton's great distance from the Sun, probably plays a crucial role. It is thought that the surface of Triton probably consists of a semi-transparent layer of frozen nitrogen white in colour, which creates a kind of greenhouse effect, heating the frozen material beneath it until it breaks the surface in an eruption. A temperature increase of just 4 K above the ambient surface temperature of 37 K could drive eruptions to the heights observed. But more likely these eruptions are caused by tidal forces.[28]
Geothermal energy may also be important. Unusually for a major satellite, Triton orbits Neptune in a retrograde orbit—that is, in the opposite direction to Neptune's rotation. This generates tidal forces which are causing Triton's orbit to decay, so that in several billion years time it will reach its Roche limit[29] with Neptune. The tidal forces may also generate heat inside Triton, in the same way as Jupiter's gravity generates tidal forces on Io which drive its extreme volcanic activity.[28]
Each eruption of a Triton geyser may last up to a year, and during this time about 0.1 [[]] (Expression error: Missing operand for *. [[]]) of material may be deposited downwind. Voyager's images of Triton's southern hemisphere show many streaks of dark material laid down by geyser activity.[28]
# Notes
- ↑ Bryan, T.S. 1995
- ↑ Jump up to: 2.0 2.1 2.2 2.3 How geysers form Gregory L. Jones; wyojones.com Retrieved on 2008-04-05
- ↑ Jump up to: 3.0 3.1 3.2 3.3 3.4 Lee Krystek Weird Geology: Geysers unmuseum.org Retrieved on 2008-03-28
- ↑ Yellowstone thermal features Yahoo! Inc. Retrieved on 2008-04-02
- ↑ Jump up to: 5.0 5.1 5.2 Plumbing system Advameg Inc. Retrieved on 2008-04-02
- ↑ Jump up to: 6.0 6.1 Lethe E. Morrison, Fred W. Tanner; Studies on Thermophilic Bacteria
Botanical Gazette, Vol. 77, No. 2 (Apr., 1924), pp. 171-185
- ↑ Michael T. Madigan and Barry L. Marrs; Extremophiles atropos.as.arizona.edu Retrieved on 2008-04-01
- ↑ Vielle, C.; Zeikus, G.J. Hyperthermophilic Enzymes: Sources, Uses, and Molecular Mechanisms for Thermostability. Microbiology and Molecular Biology Reviews. 2001, 65(1), 1-34.
- ↑ Industrial Uses of Thermophilic Cellulase University of Delaware, Retrieved on 2008-03-29
- ↑ Glennon, J.A. and Pfaff R.M. 2003; Bryan 1995
- ↑ Jump up to: 11.0 11.1 11.2 11.3 11.4 11.5 11.6 Glennon, J Allan"World Geyser Fields" Retrieved on 2008-04-04
- ↑ "Yellowstone geysers" nps.gov Retrieved on 2008-03-20
- ↑ Mehta, Aalok (2008-04-16). "Photo in the News: Russia's Valley of the Geysers Lost in Landslide". National Geographic. Retrieved 2007-06-07..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
- ↑ Harding, Luke (2007-06-05). "Mudslide fully changes terrain in Kamchatka's Valley of Geysers". Guardian Unlimited. Retrieved 2008-04-16.
- ↑ Shpilenok, Igor. "June 2007 Special release - The Natural Disaster at the Valley of the Geysers". Retrieved 2008-04-16. Text "date-2007-06-09" ignored (help)
- ↑ Glennon, J.A. and Pfaff. R.M., 2003)
- ↑ Gamble, J. A., I. C. Wright and J. A. Baker (1993). "Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand" New Zealand Journal of Geology and Geophysics, 36, 417-435.
- ↑ Central North Island sitting on magma film Paul Easton, The Dominion Post, 15 September 2007. Retrieved 2008-04-16
- ↑ Gardner Servian, Solveig"Geysers of Iceland" Retrieved on 2008-04-16
- ↑ "Whakarewarewa, The Thermal Village" Retrieved 2008-04-04
- ↑ Jones, Wyoming "Old Faithful Geyser of California" WyoJones' Geyser Pages Retrieved on 2008-03-31
- ↑ Glennon, J. Alan"Carbon-Dioxide-Driven, Cold-Water Geysers" Retrieved on 2008-04-01
- ↑ Glennon, J.A. 2005; Glennon, J.A. and Pfaff, R.M. 2005
- ↑ WyoJones"Thermal Feature Definitions" WyoJones Retrieved on 2008-04-03
- ↑ Geysers and Energy american.edu Retrieved on 2008-04-12
- ↑ Kerry O’Banion and Charles Hall Geothermal energy and the land resource: conflicts and constraints in The Geysers- Calistoga KGRA osti.gov Retrieved on 2008-04-12
- ↑ "Triton (Voyager)". NASA (Voyager The Interstellar Mission). June 1, 2005. Retrieved 2008-04-03. Check date values in: |date= (help)
- ↑ Jump up to: 28.0 28.1 28.2 Kirk, R.L., Branch of Astrogeology"Thermal Models of Insolation-driven Nitrogen Geysers on Triton" Harvard Retrieved 2008-04-08
- ↑ "Roche Limit"Harvard Retrieved 2008-04-08 | https://www.wikidoc.org/index.php/Geyser | |
32ae66d86565b4787a57c317e2fe2772b122a57e | wikidoc | Ginger | Ginger
Ginger is the common name for the monocotyledonous perennial plant Zingiber officinale. The term is also used to describe the edible part of the plant which is commonly used as a spice in cooking throughout the world. Often erroneously referred to as "ginger root", the edible section is actually the horizontal subterranean stem or rhizome of the plant. The ginger plant has a long history of cultivation known to originate in China and then spread to India, Southeast Asia, West Africa, and the Caribbean.
# Chemistry
Ginger contains up to 3% of an essential oil that causes the fragrance of the spice. The main constituents are sesquiterpenoids with (-)-zingiberene as the main component. Lesser amounts of other sesquiterpenoids (β-sesquiphellandrene, bisabolene and farnesene) and a small monoterpenoid fraction (β-phelladrene, cineol, and citral) have also been identified.
The pungent taste of ginger is due to nonvolatile phenylpropanoid-derived compounds, particularly gingerols and shogaols. The latter are formed from the former when ginger is dried or cooked. Zingerone is also produced from gingerols during this process, and it is less pungent and has a spicy-sweet aroma.
# Culinary uses
Young ginger rhizomes are juicy and fleshy with a very mild taste. They are often pickled in vinegar or sherry as a snack or just cooked as an ingredient in many dishes. They can also be stewed in boiling water to make ginger tea, to which honey is often added as a sweetener; sliced orange or lemon fruit may also be added. Mature ginger roots are fibrous and nearly dry. The juice from old ginger roots is extremely potent and is often used as a spice in Chinese cuisine to flavor dishes such as seafood or mutton.
Ginger is also made into candy and used as a flavoring for cookies, crackers and cake, and is the main flavor in ginger ale-- a sweet, carbonated, non-alcoholic beverage, as well as the similar, but somewhat spicier beverage ginger beer. A ginger-flavored liqueur called Canton is produced in Jarnac, France. Green ginger wine is a ginger flavoured wine produced in the United Kingdom by Crabbie's and Stone's and traditionally sold in a green glass bottle. Ginger is also used as a spice added to hot coffee and tea.
In Arabic, ginger is called Zanjabil and in some parts of the Middle East ginger powder is used as a spice for coffee.
In India, ginger is called "Shoonti" in Kannada language, Allam in Telugu, Inji in Tamil and Malayalam, Alay in Marathi and Adrak in Hindi and Urdu. Fresh ginger is one of the main spices used for making pulse and lentil curries and other vegetable preparations. It is used fresh to spice tea especially in winter. Also, ginger powder is used in certain food preparations that are made particularly for expecting women and feeding mothers, the most popular one being Katlu which is a mixture of gum resin, ghee, nuts and sugar.
In south India, ginger is used in the production of a candy called Inji-murappa ("ginger candy" from Tamil). This candy is mostly sold by vendors to bus passengers in bus stops and in small tea shops as a locally produced item. Candied ginger is also very famous around these parts. Additionally, in Tamil Nadu, especially in the Tanjore belt, a variety of ginger which is less spicy is used when tender to make fresh pickle with the combination of lemon juice or vinegar, salt and tender green chillies. This kind of pickle was generally made before the invention of refrigeration and stored for a maximum of 4-5 days. The pickle gains a mature flavor when the juices cook the ginger over the first 24 hours. Ginger is also added as a flavouring in tea.
In Japan, ginger is pickled to make beni shoga and gari or grated and used raw on tofu or noodles.
In Western cuisine, ginger is traditionally restricted to sweet foods, such as ginger ale, gingerbread, ginger snaps, ginger cake and ginger biscuits.
Powdered dry ginger root (ginger powder) is typically used to add spiciness to gingerbread and other recipes. Ground and fresh ginger taste quite different and ground ginger is a particularly poor substitute for fresh ginger. Fresh ginger can be successfully substituted for ground ginger and should be done at a ratio of 6 parts fresh for 1 part ground. You generally achieve better results by substituting only half the ground ginger for fresh ginger.
In Myanmar, ginger is used in a salad dish called gyin-tho, which consists of shredded ginger preserved in oil, and a variety of nuts and seeds.
Indonesia has a famous beverage that called Wedang Jahe, which is made from ginger and palm sugar.
In traditional Korean Kimchi, ginger is finely minced and added to the ingredients of the spicy paste just before the fermenting process.
In South East Asia, the flower of a type of ginger is used in cooking. This unopened flower is known in the Malay language as Bunga Kantan, and is used in salads and also as garnish for sour-savoury soups, like Assam Laksa.
Ginger has a sialagogue action, stimulating the production of saliva.
# Medical uses
The medical form of ginger historically was called "Jamaica ginger"; it was classified as a stimulant and carminative, and used frequently for dyspepsia and colic. It was also frequently employed to disguise the taste of medicines. Ginger is on the FDA's 'generally recognized as safe' list, though it does interact with some medications, including warfarin. Ginger is contraindicated in people suffering from gallstones as the herb promotes the release of bile from the gallbladder. Ginger may also decrease joint pain from arthritis, though studies on this have been inconsistent, and may have blood thinning and cholesterol lowering properties that may make it useful for treating heart disease.
The characteristic odor and flavor of ginger root is caused by a mixture of zingerone, shoagoles and gingerols, volatile oils that compose about one to three percent of the weight of fresh ginger. In laboratory animals, the gingerols increase the motility of the gastrointestinal tract and have analgesic, sedative, antipyretic and antibacterial properties
## Nausea
Ginger has been found effective by multiple studies for treating nausea caused by seasickness, morning sickness and chemotherapy, though ginger was not found superior over a placebo for post-operative nausea.
Modern research on nausea and motion sickness used approximately 1 gram of ginger powder daily. Though there are claims for efficacy in all causes of nausea, the Physicians Desk Reference recommends against taking ginger rhizomes for morning sickness commonly associated with pregnancy due to possible mutagenic effects, though Chinese women have traditionally used ginger rhizomes during pregnancy to combat morning sickness and the Natural Medicines Comprehensive Database states that it is likely safe for use in pregnancy when consumed in food-amounts.
# Folk medicinal uses
Tea brewed from this root is a folk remedy for colds. Ginger ale and ginger beer have been recommended as "stomach settlers" for generations in countries where the beverages are made and ginger water was commonly used to avoid heat cramps in the US. Ginger has also been historically used to treat inflammation, which some scientific studies support while others show ginger to be no better than a placebo or ibuprofen.
## Local uses
In the West, powdered dried ginger root is made into capsules and sold in pharmacies for medicinal use.
- In the United States, ginger is generally recognized as safe by the Food and Drug Administration, though it is not approved for the treatment or cure of any disease and is sold as an unregulated dietary supplement
- In India, ginger is applied as a paste to the temples to relieve headache and consumed when suffering from a cold
- In Myanmar, ginger and local sweet (Htan nyat) which is made from palm tree juice are boiled together and taken to prevent the flu
- In China, a drink made with sliced ginger cooked in sweetened water or a cola is used as a folk medicine for common cold
- In Indonesia, a type of ginger known as Jahe is used as a herbal preparation to reduce fatigue, reducing "winds" in blood streams, prevent and cure rheumatism and controlling poor dietary habits
- In Democratic Republic of the Congo, ginger is crushed and mixed with mango-tree sap to make Tangawisi juice, which is considered as "universal" panacea.
- In Ivory Coast, ginger is ground and mixed with orange, pineapple and lemon to produce a very refreshing juice called Nyamanku.
# Reactions
Allergic reactions to ginger generally result in a rash and though generally recognized as safe, ginger can cause heartburn, bloating, gas, belching and nausea, particularly if taken in powdered form. Unchewed fresh ginger may result in intestinal blockage, and individuals who have had ulcers, inflammatory bowel disease or blocked intestines may react badly to large quantities of fresh ginger. Ginger can also adversely affect individuals with gallstones. There are also suggestions that ginger may affect blood pressure, clotting, and heart rhythms.
# Horticulture
Ginger produces clusters of white and pink flower buds that bloom into yellow flowers. Because of the aesthetic appeal and the adaptivity of the plant to warm climates, ginger is often used as landscaping around subtropical homes. It is a perennial reed-like plant with annual leafy stems, three to four feet high.
Historical methods of gathering the root describes, when the stalk withers, it is immediately scalded, or washed and scraped, in order to kill it and prevent sprouting. The former method, applied generally to the older and poorer roots, produces Black Ginger; the latter, gives White Ginger. The natural color of the "white" scraped ginger is a pale buff--it is often whitened by bleaching or liming, but generally at the expense of some of its real value.
# References in popular culture
- To members of the Race, an alien species in Harry Turtledove's best-selling novel series Worldwar, ginger is a highly addictive, psychoactive drug, with an effect similar to that of cocaine or PCP in humans.
- In Cockney rhyming slang, ginger is a derogatory euphemism for homosexual. The original slang rhymed queer with ginger beer.
- In the west of Scotland (particularly Glasgow), ginger is a term for any carbonated soft drink.
- Before the First World War, it was common for mounted regiments to receive large vats of root ginger before public ceremonies, which were peeled and cut into suppositories for the horses. The burning sensation made the horses hold their tails up; this practice is called Figging or feaguing.
- Ginger is also a common slang term in Great Britain for red-haired individuals. This term is also used in the South Park in episode Ginger Kids. In Harry Potter and the Deathly Hallows, the drunk men yelling at Hermione used the term "Ginger" to describe Ron's red hair.
# Production trends
In 2005, China continued to lead the world in ginger production with a global share of almost 25% followed by India, Nepal and Indonesia.
# Similar species
Myoga (Zingiber mioga Roscoe) appears in Japanese cuisine; the flower buds are the part eaten.
Another plant in the Zingiberaceae family, galangal, is used for similar purposes as ginger in Thai cuisine. Galangal is also called Thai ginger. Also referred to as galangal, fingerroot (Boesenbergia rotunda), or Chinese ginger or the Thai krachai, is used in cooking and medicine.
A dicotyledonous native species of eastern
North America, Asarum canadense, is also known as "wild ginger", and its root has similar aromatic properties, but it is not related to true ginger and should not be used as a substitute because it contains the carcinogen aristolochic acid. This plant is also a powerful diuretic, or urinary stimulator. It is part of the Aristolochiaceae family. | Ginger
Ginger is the common name for the monocotyledonous perennial plant Zingiber officinale. The term is also used to describe the edible part of the plant which is commonly used as a spice in cooking throughout the world. Often erroneously referred to as "ginger root", the edible section is actually the horizontal subterranean stem or rhizome of the plant. The ginger plant has a long history of cultivation known to originate in China and then spread to India, Southeast Asia, West Africa, and the Caribbean.[1]
# Chemistry
Ginger contains up to 3% of an essential oil that causes the fragrance of the spice. The main constituents are sesquiterpenoids with (-)-zingiberene as the main component. Lesser amounts of other sesquiterpenoids (β-sesquiphellandrene, bisabolene and farnesene) and a small monoterpenoid fraction (β-phelladrene, cineol, and citral) have also been identified.
The pungent taste of ginger is due to nonvolatile phenylpropanoid-derived compounds, particularly gingerols and shogaols. The latter are formed from the former when ginger is dried or cooked. Zingerone is also produced from gingerols during this process, and it is less pungent and has a spicy-sweet aroma.[2]
# Culinary uses
Template:Nutritionalvalue
Young ginger rhizomes are juicy and fleshy with a very mild taste. They are often pickled in vinegar or sherry as a snack or just cooked as an ingredient in many dishes. They can also be stewed in boiling water to make ginger tea, to which honey is often added as a sweetener; sliced orange or lemon fruit may also be added. Mature ginger roots are fibrous and nearly dry. The juice from old ginger roots is extremely potent and is often used as a spice in Chinese cuisine to flavor dishes such as seafood or mutton.
Ginger is also made into candy and used as a flavoring for cookies, crackers and cake, and is the main flavor in ginger ale-- a sweet, carbonated, non-alcoholic beverage, as well as the similar, but somewhat spicier beverage ginger beer. A ginger-flavored liqueur called Canton is produced in Jarnac, France. Green ginger wine is a ginger flavoured wine produced in the United Kingdom by Crabbie's and Stone's and traditionally sold in a green glass bottle. Ginger is also used as a spice added to hot coffee and tea.
In Arabic, ginger is called Zanjabil and in some parts of the Middle East ginger powder is used as a spice for coffee.
In India, ginger is called "Shoonti" in Kannada language[Karnataka], Allam in Telugu, Inji in Tamil and Malayalam, Alay in Marathi and Adrak in Hindi and Urdu. Fresh ginger is one of the main spices used for making pulse and lentil curries and other vegetable preparations. It is used fresh to spice tea especially in winter. Also, ginger powder is used in certain food preparations that are made particularly for expecting women and feeding mothers, the most popular one being Katlu which is a mixture of gum resin, ghee, nuts and sugar.
In south India, ginger is used in the production of a candy called Inji-murappa ("ginger candy" from Tamil). This candy is mostly sold by vendors to bus passengers in bus stops and in small tea shops as a locally produced item. Candied ginger is also very famous around these parts. Additionally, in Tamil Nadu, especially in the Tanjore belt, a variety of ginger which is less spicy is used when tender to make fresh pickle with the combination of lemon juice or vinegar, salt and tender green chillies. This kind of pickle was generally made before the invention of refrigeration and stored for a maximum of 4-5 days. The pickle gains a mature flavor when the juices cook the ginger over the first 24 hours. Ginger is also added as a flavouring in tea.
In Japan, ginger is pickled to make beni shoga and gari or grated and used raw on tofu or noodles.
In Western cuisine, ginger is traditionally restricted to sweet foods, such as ginger ale, gingerbread, ginger snaps, ginger cake and ginger biscuits.
Powdered dry ginger root (ginger powder) is typically used to add spiciness to gingerbread and other recipes. Ground and fresh ginger taste quite different and ground ginger is a particularly poor substitute for fresh ginger. Fresh ginger can be successfully substituted for ground ginger and should be done at a ratio of 6 parts fresh for 1 part ground. You generally achieve better results by substituting only half the ground ginger for fresh ginger.
In Myanmar, ginger is used in a salad dish called gyin-tho, which consists of shredded ginger preserved in oil, and a variety of nuts and seeds.
Indonesia has a famous beverage that called Wedang Jahe, which is made from ginger and palm sugar.
In traditional Korean Kimchi, ginger is finely minced and added to the ingredients of the spicy paste just before the fermenting process.
In South East Asia, the flower of a type of ginger is used in cooking. This unopened flower is known in the Malay language as Bunga Kantan, and is used in salads and also as garnish for sour-savoury soups, like Assam Laksa.
Ginger has a sialagogue action, stimulating the production of saliva.
# Medical uses
The medical form of ginger historically was called "Jamaica ginger"; it was classified as a stimulant and carminative, and used frequently for dyspepsia and colic. It was also frequently employed to disguise the taste of medicines. Ginger is on the FDA's 'generally recognized as safe' list, though it does interact with some medications, including warfarin. Ginger is contraindicated in people suffering from gallstones as the herb promotes the release of bile from the gallbladder.[3] Ginger may also decrease joint pain from arthritis, though studies on this have been inconsistent, and may have blood thinning and cholesterol lowering properties that may make it useful for treating heart disease. [4]
The characteristic odor and flavor of ginger root is caused by a mixture of zingerone, shoagoles and gingerols, volatile oils that compose about one to three percent of the weight of fresh ginger. In laboratory animals, the gingerols increase the motility of the gastrointestinal tract and have analgesic, sedative, antipyretic and antibacterial properties [5]
## Nausea
Ginger has been found effective by multiple studies for treating nausea caused by seasickness, morning sickness and chemotherapy,[6] though ginger was not found superior over a placebo for post-operative nausea.
Modern research on nausea and motion sickness used approximately 1 gram of ginger powder daily. Though there are claims for efficacy in all causes of nausea, the Physicians Desk Reference recommends against taking ginger rhizomes for morning sickness commonly associated with pregnancy due to possible mutagenic effects,[citation needed] though Chinese women have traditionally used ginger rhizomes during pregnancy to combat morning sickness and the Natural Medicines Comprehensive Database states that it is likely safe for use in pregnancy when consumed in food-amounts.[citation needed]
# Folk medicinal uses
Tea brewed from this root is a folk remedy for colds. Ginger ale and ginger beer have been recommended as "stomach settlers" for generations in countries where the beverages are made and ginger water was commonly used to avoid heat cramps in the US. Ginger has also been historically used to treat inflammation, which some scientific studies support while others show ginger to be no better than a placebo or ibuprofen.[4]
## Local uses
In the West, powdered dried ginger root is made into capsules and sold in pharmacies for medicinal use.
- In the United States, ginger is generally recognized as safe by the Food and Drug Administration, though it is not approved for the treatment or cure of any disease and is sold as an unregulated dietary supplement
- In India, ginger is applied as a paste to the temples to relieve headache and consumed when suffering from a cold
- In Myanmar, ginger and local sweet (Htan nyat) which is made from palm tree juice are boiled together and taken to prevent the flu
- In China, a drink made with sliced ginger cooked in sweetened water or a cola is used as a folk medicine for common cold[7]
- In Indonesia, a type of ginger known as Jahe is used as a herbal preparation to reduce fatigue, reducing "winds" in blood streams, prevent and cure rheumatism and controlling poor dietary habits
- In Democratic Republic of the Congo, ginger is crushed and mixed with mango-tree sap to make Tangawisi juice, which is considered as "universal" panacea.
- In Ivory Coast, ginger is ground and mixed with orange, pineapple and lemon to produce a very refreshing juice called Nyamanku.
# Reactions
Allergic reactions to ginger generally result in a rash and though generally recognized as safe, ginger can cause heartburn, bloating, gas, belching and nausea, particularly if taken in powdered form. Unchewed fresh ginger may result in intestinal blockage, and individuals who have had ulcers, inflammatory bowel disease or blocked intestines may react badly to large quantities of fresh ginger.[8] Ginger can also adversely affect individuals with gallstones.[4][8] There are also suggestions that ginger may affect blood pressure, clotting, and heart rhythms.[8]
# Horticulture
Ginger produces clusters of white and pink flower buds that bloom into yellow flowers. Because of the aesthetic appeal and the adaptivity of the plant to warm climates, ginger is often used as landscaping around subtropical homes. It is a perennial reed-like plant with annual leafy stems, three to four feet high.
Historical methods of gathering the root describes, when the stalk withers, it is immediately scalded, or washed and scraped, in order to kill it and prevent sprouting. The former method, applied generally to the older and poorer roots, produces Black Ginger; the latter, gives White Ginger. The natural color of the "white" scraped ginger is a pale buff--it is often whitened by bleaching or liming, but generally at the expense of some of its real value.
# References in popular culture
- To members of the Race, an alien species in Harry Turtledove's best-selling novel series Worldwar, ginger is a highly addictive, psychoactive drug, with an effect similar to that of cocaine or PCP in humans.
- In Cockney rhyming slang, ginger is a derogatory euphemism for homosexual. The original slang rhymed queer with ginger beer.
- In the west of Scotland (particularly Glasgow), ginger is a term for any carbonated soft drink.
- Before the First World War, it was common for mounted regiments to receive large vats of root ginger before public ceremonies, which were peeled and cut into suppositories for the horses. The burning sensation made the horses hold their tails up; this practice is called Figging or feaguing.
- Ginger is also a common slang term in Great Britain for red-haired individuals. This term is also used in the South Park in episode Ginger Kids. In Harry Potter and the Deathly Hallows, the drunk men yelling at Hermione used the term "Ginger" to describe Ron's red hair.
# Production trends
In 2005, China continued to lead the world in ginger production with a global share of almost 25% followed by India, Nepal and Indonesia.
# Similar species
Myoga (Zingiber mioga Roscoe) appears in Japanese cuisine; the flower buds are the part eaten.
Another plant in the Zingiberaceae family, galangal, is used for similar purposes as ginger in Thai cuisine. Galangal is also called Thai ginger. Also referred to as galangal, fingerroot (Boesenbergia rotunda), or Chinese ginger or the Thai krachai, is used in cooking and medicine.
A dicotyledonous native species of eastern
North America, Asarum canadense, is also known as "wild ginger", and its root has similar aromatic properties, but it is not related to true ginger and should not be used as a substitute because it contains the carcinogen aristolochic acid. This plant is also a powerful diuretic, or urinary stimulator. It is part of the Aristolochiaceae family. | https://www.wikidoc.org/index.php/Ginger | |
61d96fa3b2282a685f5dbf45cebb6cbf6f7ef730 | wikidoc | Gluten | Gluten
Gluten is a mixture of the proteins gliadin and glutenin. These exist, conjoined with starch, in the endosperms of some grass-related grains, notably wheat, rye, and barley. Gliadin and glutenin comprise about 80% of the protein contained in wheat seed. Being insoluble in water, they can be purified by washing away the associated starch. Worldwide, gluten is an important source of nutritional protein, both in foods prepared directly from foods containing it, and as an additive to foods otherwise low in protein.
The seeds of most flowering plants have endosperms with stored protein to nourish embryonic plants during germination, but true gluten, with gliadin and glutenin, is limited to certain members of the grass family. The stored proteins of corn and rice are sometimes called glutens, but their proteins differ importantly from wheat gluten by lacking glutenin. The glutenin in wheat flour gives kneaded dough its elasticity, allowing leavening and contributing chewiness to baked products like bagels.
Although wheat supplies much of the world's dietary protein, a small percentage of the populace, including those with coeliac disease, is gluten-intolerant and cannot consume it safely.
# Extraction
Legend attributes the discovery of gluten to Buddhist monks in 7th century China who sought meat-like ingredients for use in their vegetarian diet. With easily available wheat flour and water they made a dough which they submerged in cold water and kneaded. The water dissolved the starchy components of the dough and left behind an insoluble, gummy mass, 70% to 80% of which was gluten.
Gluten is still extracted from flour by washing out the starch by means not fundamentally different from the ancient way, which exploited the fact that starch is water-soluble while gluten is not -- also, that gluten binds together strongly, while starch dissolved in cold water is mobile. If a saline solution is used instead of water a purer protein is obtained, with certain harmless impurities going into solution with the starch. However, on an industrial scale, starch is the prime product, so cold water is the favored solvent. To effect the separation, a slurry of wheat flour is stirred vigorously by machinery until the starch dissolves and the gluten consolidates into a mass, which is collected by centrifugation, then carried, by complex machinery, through several stages combined into a continuous process: Approximately 65% of the water in the wet gluten is removed by means of a screw press, and the residue is sprayed through an atomizing nozzle into a drying chamber, where it remains at an elevated temperature only long enough to evaporate the water without denaturing the gluten. This yields a flour-like powder with a 7% moisture content, which is quickly air-cooled and pneumatically transported to a receiving vessel. In the final step, the collected gluten is sifted and milled to make the product uniform.
# Uses
When cooked in broth, gluten absorbs some of the surrounding liquid (including the taste) and becomes firm to the bite, so is often used in vegetarian, vegan and Buddhist cuisines as a meat substitute. In China, as miàn jīn (Template:Zh-t) , it is the basis for imitation meats resembling chicken, duck, fish, pork and beef. The Japanese variants, called namafu, yakifu, or seitan is used in the same way.
When dough made with wheat flour is kneaded, the gluten molecules cross-link to form a sub-microscopic network. If such dough is leavened with yeast, sugar fermentation produces bubbles of carbon dioxide which are trapped by the gluten network, causing the dough to swell or rise. Baking coagulates the gluten, which, along with starch, stabilizes the shape of the final product.
Gluten content has been implicated as a factor in the staling of bread, possibly because it binds water by hydration.
The development of gluten (i.e., enhancing its elasticity) affects the texture of the baked goods. Gluten's attainable elasticity is proportional to its content of glutenins with low molecular weights because that fraction contains the preponderance of the sulfur atoms responsible for the cross-linking in the network.
More development leads to chewier products like pizza and bagels, while less development yields tender baked goods such as pie crust. Several other factors affect the development of gluten in baked goods:
- The amount of gluten in the flour. For examples, bread flour has high gluten content, while cake flour is low in gluten.
- Fat inhibits the formation of long gluten strands, so increased shortening yields a more tender product.
- Kneading develops the gluten strands, so a baked product is chewier in proportion to how much the dough is worked.
- Water is essential to gluten development, so more of it is used in doughs when a chewier texture is desired.
Gluten can be dried and milled into a flour or powder, which, added to ordinary flour dough, makes for higher rising and increases the bread's structural stability and chewiness.. Since such doughs must be worked vigorously if they are to rise to their full capacity, a bread machine or food processor may be required for their kneading.
Gluten is used as a protein supplement, especially in low-carbohydrate baked goods where it replaces flour. It is also added to many pet foods to increase their protein content.
# Occurrence
Strictly speaking, gluten is the non-starch (proteinaceous) component of wheat that allows bread dough to rise. Wheat gluten is found to contain albumin, globulins, glutelins and prolamins. The 'sticky' proteins in the gluten that facilitate bread making are known as gliadin (wheat prolamins) and glutenin (wheat glutelins).
Glutenin from wheat possesses one additional property that makes bread gluten unique; it is an elastic protein, but on heat denaturation, fixes it shape. This prevents bread from collapsing after cooking.
Because wheat is made of three grass genomes (AA, BB, DD allohexaploid), the amount of glutinous protein is higher than most related species. Wheat grown in countries with cold growing seasons, e.g. Canada, tends to have a higher gluten content than wheat grown in countries with mild climates.
High levels of glutens are important for some baking procedures, others require less gluten. Wheat flour with a high gluten content is called "strong" or "hard" flour, and is used for breads, whereas flour with a lower gluten content is called "soft" flour, and is used for cakes.
## Glutinous cereals
Gluten is derived from the Latin word glūten, meaning glue. Such 'sticky' proteins are found over the seed producing species and include other seeds like corn, rice, and soy. Glutinous ('sticky') strains and preparations (for example: glutinous rice (aka sticky rice), or corn gluten feed), are used widely to describe the products enriched with the seed storage proteins of cereals -- although in the case of glutinous rice, the stickiness is inherent in the natural grain of at least some types. Some of these proteins are useful in making gluten-free breads but most require some form of supplementation (xanthum gum or gum arabic). As a result gluten is widely used to describe similar proteins
(particularly prolamins) from other cereal species.
# Adverse reactions
Between 0.5 and 1.0 percent of the United States populace is sensitive to gluten.
Coeliac disease (or celiac disease, also called gluten sensitive enteropathy (GSE)), is the predominant disorder caused by gluten sensitivity. GSE is an abnormal immune reaction to digestive breakdown products of gliadin. This process damages the lining of the small intestine, which results in chronic malnutrition. Treatment requires a lifelong gluten-free diet and avoiding exposure to air-borne gluten-containing particles such as wheat flour. Gluten allergies and gluten-sensitive idiopathic neuropathies are two other adverse reactions to gluten.
Patients with conditions associated with GSE also benefit from a gluten-free diet and avoiding gluten inhalation. An example of gluten-related skin sensitivity is dermatitis herpetiformis, an intensely itchy skin eruption, which is nearly always accompanied by coeliac disease. This dermatitis usually develops in young adults, predominantly in males; people of North European ethnicity are especially susceptible.
A different, clinical definition of gluten has developed as a result of the determination of wheat gluten as the fraction of wheat that caused coeliac disease. Purification of the gluten proteins first revealed wheat gliadin as the culprit. Proteins from other cereals, even in small amounts, can cause the pathology to persist. Wheat gluten, and the similar proteins within the pure cereals of the grass tribe Triticeae (cultivars are wheats, barleys and ryes) can mediate enteropathy for the majority of affected individuals. These T-cell activating sites are also found in other the Triticeae genera including Aegilops. Therefore, these relatives of wheat are also commonly considered as having gluten.
Studies of the oat gluten avenin have revealed that pathogenic prolamins are either not present, strain specific or weakly stimulatory. For some 2% of coeliacs, 'gluten-free' extends to the foods free of oats glutens. | Gluten
Gluten is a mixture of the proteins gliadin and glutenin. These exist, conjoined with starch, in the endosperms of some grass-related grains, notably wheat, rye, and barley. Gliadin and glutenin comprise about 80% of the protein contained in wheat seed. Being insoluble in water, they can be purified by washing away the associated starch. Worldwide, gluten is an important source of nutritional protein, both in foods prepared directly from foods containing it, and as an additive to foods otherwise low in protein.
The seeds of most flowering plants have endosperms with stored protein to nourish embryonic plants during germination, but true gluten, with gliadin and glutenin, is limited to certain members of the grass family. The stored proteins of corn and rice are sometimes called glutens, but their proteins differ importantly from wheat gluten by lacking glutenin. The glutenin in wheat flour gives kneaded dough its elasticity, allowing leavening and contributing chewiness to baked products like bagels.
Although wheat supplies much of the world's dietary protein, a small percentage of the populace, including those with coeliac disease, is gluten-intolerant and cannot consume it safely. [1]
# Extraction
Legend attributes the discovery of gluten to Buddhist monks in 7th century China who sought meat-like ingredients for use in their vegetarian diet. With easily available wheat flour and water they made a dough which they submerged in cold water and kneaded. The water dissolved the starchy components of the dough and left behind an insoluble, gummy mass, 70% to 80% of which was gluten.[2]
Gluten is still extracted from flour by washing out the starch by means not fundamentally different from the ancient way, which exploited the fact that starch is water-soluble while gluten is not -- also, that gluten binds together strongly, while starch dissolved in cold water is mobile. If a saline solution is used instead of water a purer protein is obtained, with certain harmless impurities going into solution with the starch. However, on an industrial scale, starch is the prime product, so cold water is the favored solvent. To effect the separation, a slurry of wheat flour is stirred vigorously by machinery until the starch dissolves and the gluten consolidates into a mass, which is collected by centrifugation, then carried, by complex machinery,[3] through several stages combined into a continuous process: Approximately 65% of the water in the wet gluten is removed by means of a screw press, and the residue is sprayed through an atomizing nozzle into a drying chamber, where it remains at an elevated temperature only long enough to evaporate the water without denaturing the gluten. This yields a flour-like powder with a 7% moisture content, which is quickly air-cooled and pneumatically transported to a receiving vessel. In the final step, the collected gluten is sifted and milled to make the product uniform. [4]
# Uses
When cooked in broth, gluten absorbs some of the surrounding liquid (including the taste) and becomes firm to the bite, so is often used in vegetarian, vegan and Buddhist cuisines as a meat substitute. In China, as miàn jīn (Template:Zh-t) , it is the basis for imitation meats resembling chicken, duck, fish, pork and beef. The Japanese variants, called namafu, yakifu, or seitan is used in the same way.
When dough made with wheat flour is kneaded, the gluten molecules cross-link to form a sub-microscopic network. If such dough is leavened with yeast, sugar fermentation produces bubbles of carbon dioxide which are trapped by the gluten network, causing the dough to swell or rise. Baking coagulates the gluten, which, along with starch, stabilizes the shape of the final product.
Gluten content has been implicated as a factor in the staling of bread, possibly because it binds water by hydration.[5]
The development of gluten (i.e., enhancing its elasticity) affects the texture of the baked goods. Gluten's attainable elasticity is proportional to its content of glutenins with low molecular weights because that fraction contains the preponderance of the sulfur atoms responsible for the cross-linking in the network.[6][7]
More development leads to chewier products like pizza and bagels, while less development yields tender baked goods such as pie crust. Several other factors affect the development of gluten in baked goods:
- The amount of gluten in the flour. For examples, bread flour has high gluten content, while cake flour is low in gluten.
- Fat inhibits the formation of long gluten strands, so increased shortening yields a more tender product.
- Kneading develops the gluten strands, so a baked product is chewier in proportion to how much the dough is worked.
- Water is essential to gluten development, so more of it is used in doughs when a chewier texture is desired.[8]
Gluten can be dried and milled into a flour or powder, which, added to ordinary flour dough, makes for higher rising and increases the bread's structural stability and chewiness.[9]. Since such doughs must be worked vigorously if they are to rise to their full capacity, a bread machine or food processor may be required for their kneading.[10]
Gluten is used as a protein supplement, especially in low-carbohydrate baked goods where it replaces flour. It is also added to many pet foods to increase their protein content.[11]
# Occurrence
Strictly speaking, gluten is the non-starch (proteinaceous) component of wheat that allows bread dough to rise. Wheat gluten is found to contain albumin, globulins, glutelins and prolamins. The 'sticky' proteins in the gluten that facilitate bread making are known as gliadin (wheat prolamins) and glutenin (wheat glutelins).[12]
Glutenin from wheat possesses one additional property that makes bread gluten unique; it is an elastic protein, but on heat denaturation, fixes it shape. This prevents bread from collapsing after cooking.
Because wheat is made of three grass genomes (AA, BB, DD allohexaploid), the amount of glutinous protein is higher than most related species. Wheat grown in countries with cold growing seasons, e.g. Canada, tends to have a higher gluten content than wheat grown in countries with mild climates.
High levels of glutens are important for some baking procedures, others require less gluten. Wheat flour with a high gluten content is called "strong" or "hard" flour, and is used for breads, whereas flour with a lower gluten content is called "soft" flour, and is used for cakes.
## Glutinous cereals
Gluten is derived from the Latin word glūten, meaning glue.[13] Such 'sticky' proteins are found over the seed producing species and include other seeds like corn, rice, and soy. Glutinous ('sticky') strains and preparations (for example: glutinous rice (aka sticky rice), or corn gluten feed), are used widely to describe the products enriched with the seed storage proteins of cereals -- although in the case of glutinous rice, the stickiness is inherent in the natural grain of at least some types. Some of these proteins are useful in making gluten-free breads but most require some form of supplementation (xanthum gum or gum arabic). As a result gluten is widely used to describe similar proteins
(particularly prolamins) from other cereal species.
# Adverse reactions
Between 0.5 and 1.0 percent of the United States populace is sensitive to gluten.[14]
[15] Coeliac disease (or celiac disease, also called gluten sensitive enteropathy (GSE)), is the predominant disorder caused by gluten sensitivity. GSE is an abnormal immune reaction to digestive breakdown products of gliadin. This process damages the lining of the small intestine, which results in chronic malnutrition. Treatment requires a lifelong gluten-free diet and avoiding exposure to air-borne gluten-containing particles such as wheat flour. Gluten allergies and gluten-sensitive idiopathic neuropathies are two other adverse reactions to gluten.[16]
Patients with conditions associated with GSE[14] also benefit from a gluten-free diet and avoiding gluten inhalation. An example of gluten-related skin sensitivity is dermatitis herpetiformis, an intensely itchy skin eruption, which is nearly always accompanied by coeliac disease. This dermatitis usually develops in young adults, predominantly in males; people of North European ethnicity are especially susceptible.[17]
A different, clinical definition of gluten has developed as a result of the determination of wheat gluten as the fraction of wheat that caused coeliac disease. Purification of the gluten proteins first revealed wheat gliadin as the culprit. Proteins from other cereals, even in small amounts, can cause the pathology to persist. Wheat gluten, and the similar proteins within the pure cereals of the grass tribe Triticeae (cultivars are wheats, barleys and ryes) can mediate enteropathy for the majority of affected individuals.[18][19] These T-cell activating sites are also found in other the Triticeae genera including Aegilops.[20] Therefore, these relatives of wheat are also commonly considered as having gluten.
Studies of the oat gluten avenin have revealed that pathogenic prolamins are either not present[21], strain specific[22] or weakly stimulatory.[23] For some 2% of coeliacs, 'gluten-free' extends to the foods free of oats glutens. | https://www.wikidoc.org/index.php/Gluten | |
498f48fd1bedef070acb6804f2797e542004e6e8 | wikidoc | Granin | Granin
Granin (chromogranin and secretogranin) is a protein family of regulated secretory proteins ubiquitously found in the cores of amine and peptide hormone and neurotransmitter dense-core secretory vesicles.
# Function
Granins (chromogranins or secretogranins) are acidic proteins and are present in the secretory granules of a wide variety of endocrine and neuro-endocrine cells. The exact function(s) of these proteins is not yet settled but there is evidence that granins function as pro-hormones, giving rise to an array of peptide fragments for which autocrine, paracrine, and endocrine activities have been demonstrated in vitro and in vivo. The intracellular biochemistry of granins includes binding of Ca2+, ATP and catecholamines (epinephrine, norepinephrine) within the hormone storage vesicle core. There is also evidence that CgA, and perhaps other granins, regulate the biogenesis of dense-core secretory vesicles and hormone sequestration in neuroendocrine cells.
# Structure
Apart from their subcellular location and the abundance of acidic residues (Asp and Glu), these proteins do not share many structural similarities. Only one short region, located in the C-terminal section, is conserved in all these proteins. Chromogranins and secretogranins together share a C-terminal motif, whereas chromogranins A and B share a region of high similarity in their N-terminal section; this region includes two cysteine residues involved in a disulfide bond.
There are considerable differences in the amino acid composition between different animals. Commercial assays for measuring human CGA can usually not be used for measuring CGA in samples from other species. Some specific parts of the molecule have a higher degree of amino acid homology and methods where the antibodies are directed against specific epitopes can be used to measure samples from different animals. Region-specific assays measuring defined parts of CGA, CGB and SG2 can be used for measurements in samples from cats and dogs.
# Members
## Chromogranins
- chromogranin A (CgA)
- chromogranin B (CgB)
## Secretogranins
- secretogranin II (SgII) (see also secretoneurin)
- secretogranin III (SgIII)
- secretogranin V (SgV)
Two other proteins (secretogranin IV and VI) are also proposed to belong to the granins on the basis of their physico-chemical properties. | Granin
Granin (chromogranin and secretogranin) is a protein family of regulated secretory proteins ubiquitously found in the cores of amine and peptide hormone and neurotransmitter dense-core secretory vesicles.[2]
# Function
Granins (chromogranins or secretogranins) are acidic proteins and are present in the secretory granules of a wide variety of endocrine and neuro-endocrine cells. The exact function(s) of these proteins is not yet settled but there is evidence that granins function as pro-hormones, giving rise to an array of peptide fragments for which autocrine, paracrine, and endocrine activities have been demonstrated in vitro and in vivo. The intracellular biochemistry of granins includes binding of Ca2+, ATP and catecholamines (epinephrine, norepinephrine) within the hormone storage vesicle core. There is also evidence that CgA, and perhaps other granins, regulate the biogenesis of dense-core secretory vesicles and hormone sequestration in neuroendocrine cells.
# Structure
Apart from their subcellular location and the abundance of acidic residues (Asp and Glu), these proteins do not share many structural similarities. Only one short region, located in the C-terminal section, is conserved in all these proteins. Chromogranins and secretogranins together share a C-terminal motif, whereas chromogranins A and B share a region of high similarity in their N-terminal section; this region includes two cysteine residues involved in a disulfide bond.
There are considerable differences in the amino acid composition between different animals. Commercial assays for measuring human CGA can usually not be used for measuring CGA in samples from other species. Some specific parts of the molecule have a higher degree of amino acid homology and methods where the antibodies are directed against specific epitopes can be used to measure samples from different animals.[3] Region-specific assays measuring defined parts of CGA, CGB and SG2 can be used for measurements in samples from cats and dogs.[4][5][6][7]
# Members
## Chromogranins
- chromogranin A (CgA)
- chromogranin B (CgB)
## Secretogranins
- secretogranin II (SgII) (see also secretoneurin)
- secretogranin III (SgIII)
- secretogranin V (SgV)
Two other proteins (secretogranin IV and VI) are also proposed to belong to the granins on the basis of their physico-chemical properties. | https://www.wikidoc.org/index.php/Granin | |
5c2f29ba0c00e976139476b7ca82374641232302 | wikidoc | Gypsum | Gypsum
Gypsum is a very soft mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O.
# Crystal varieties
Gypsum occurs in nature as flattened and often twinned crystals and transparent cleavable masses called selenite. It may also occur silky and fibrous, in which case it is commonly called satin spar. Finally it may also be granular or quite compact. In hand-sized samples, it can be anywhere from transparent to opaque. A very fine-grained white or lightly-tinted variety of gypsum is called alabaster, which is prized for ornamental work of various sorts. In arid areas, gypsum can occur in a flower-like form typically opaque with embedded sand grains called desert rose. The most visually striking variety, however, is the giant crystals from Naica Mine. Up to the size of 11m long, these megacrystals are among the largest crystals found in nature. A recent publication shows that these crystals are grown under constant temperature such that large crystals can grow slowly but steadily without excessive nucleation.
# Occurrence
Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as early as the Permian age. Gypsum is deposited in lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins. Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near surface exposures. It is often associated with the minerals halite and sulfur.
The word gypsum is derived from the aorist form of the Greek verb μαγειρεύω, "to cook", referring to the burnt or calcined mineral. Because the gypsum from the quarries of the Montmartre district of Paris has long furnished burnt gypsum used for various purposes, this material has been called plaster of Paris. It is also used in foot creams, shampoos and many other hair products. It is water-soluble.
Because gypsum dissolves over time in water, gypsum is rarely found in the form of sand. However, the unique conditions of the White Sands National Monument in the US state of New Mexico have created a 710 km² (275 sq mile) expanse of white gypsum sand, enough to supply the construction industry with drywall for 1,000 years. Commercial exploitation of the area, strongly opposed by area residents, was permanently prevented in 1933 when president Herbert Hoover declared the gypsum dunes a protected national monument.
Commercial quantities of gypsum are found in Jamaica, Iran, Thailand, Spain (the main producer in Europe), Germany, Italy, England, Ireland, in British Columbia, Manitoba, Ontario, Nova Scotia and Newfoundland in Canada, and in New York, Michigan, Indiana,Texas(in the Palo Duro Canyon),Iowa, Kansas, Oklahoma, Arizona, New Mexico, Colorado, Utah and Nevada in the United States. There is also a large mine located at Plaster City, California in Imperial County, and in East Kutai, Kalimantan.
Vast crystals of gypsum, up to 10 metres in length have been found in the "Cueva de los Crystales" in Naica, Chihuahua, Mexico.
# Uses of Gypsum
There are a large number of uses for gypsum throughout prehistory and history. Some of these uses are:
- Drywall
- Plaster ingredient.
- Fertilizer and soil conditioner. In the late eighteenth and early nineteenth century, Nova Scotia gypsum, often referred to as plaister, was a highly sought fertilizer for wheat fields in the United States.
- Plaster of Paris (surgical splints; casting moulds; modeling).
- A wood substitute in the ancient world; for example, when wood became scarce due to deforestation on Bronze Age Crete, gypsum was employed in building construction at locations where wood was previously used.
- A tofu (soy bean curd) coagulant, making it ultimately a major source of dietary calcium, especially in Asian cultures which traditionally use few dairy products.
- Adding hardness to water used for homebrewing.
- Blackboard chalk.
- A component of Portland cement used to prevent flash setting of concrete.
- Soil/water potential monitoring (soil moisture tension)
- A medicinal agent in traditional Chinese medicine called Shi Gao. | Gypsum
Template:Infobox mineral
Gypsum is a very soft mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O.[1]
# Crystal varieties
Gypsum occurs in nature as flattened and often twinned crystals and transparent cleavable masses called selenite. It may also occur silky and fibrous, in which case it is commonly called satin spar. Finally it may also be granular or quite compact. In hand-sized samples, it can be anywhere from transparent to opaque. A very fine-grained white or lightly-tinted variety of gypsum is called alabaster, which is prized for ornamental work of various sorts. In arid areas, gypsum can occur in a flower-like form typically opaque with embedded sand grains called desert rose. The most visually striking variety, however, is the giant crystals from Naica Mine. Up to the size of 11m long, these megacrystals are among the largest crystals found in nature. A recent publication shows that these crystals are grown under constant temperature such that large crystals can grow slowly but steadily without excessive nucleation.[2]
# Occurrence
Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as early as the Permian age.[3] Gypsum is deposited in lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins. Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near surface exposures. It is often associated with the minerals halite and sulfur.
The word gypsum is derived from the aorist form of the Greek verb μαγειρεύω, "to cook", referring to the burnt or calcined mineral. Because the gypsum from the quarries of the Montmartre district of Paris has long furnished burnt gypsum used for various purposes, this material has been called plaster of Paris. It is also used in foot creams, shampoos and many other hair products. It is water-soluble.
Because gypsum dissolves over time in water, gypsum is rarely found in the form of sand. However, the unique conditions of the White Sands National Monument in the US state of New Mexico have created a 710 km² (275 sq mile) expanse of white gypsum sand, enough to supply the construction industry with drywall for 1,000 years.[4] Commercial exploitation of the area, strongly opposed by area residents, was permanently prevented in 1933 when president Herbert Hoover declared the gypsum dunes a protected national monument.
Commercial quantities of gypsum are found in Jamaica, Iran, Thailand, Spain (the main producer in Europe), Germany, Italy, England, Ireland, in British Columbia, Manitoba, Ontario, Nova Scotia and Newfoundland in Canada,[5] and in New York, Michigan, Indiana[5],Texas(in the Palo Duro Canyon),Iowa, Kansas, Oklahoma, Arizona, New Mexico, Colorado, Utah and Nevada in the United States. There is also a large mine located at Plaster City, California in Imperial County, and in East Kutai, Kalimantan.
Vast crystals of gypsum, up to 10 metres in length have been found in the "Cueva de los Crystales" in Naica, Chihuahua, Mexico.[6]
# Uses of Gypsum
Template:Cleanup-laundry
There are a large number of uses for gypsum throughout prehistory and history. Some of these uses are:
- Drywall
- Plaster ingredient.
- Fertilizer and soil conditioner. In the late eighteenth and early nineteenth century, Nova Scotia gypsum, often referred to as plaister, was a highly sought fertilizer for wheat fields in the United States.
- Plaster of Paris (surgical splints; casting moulds; modeling).
- A wood substitute in the ancient world; for example, when wood became scarce due to deforestation on Bronze Age Crete, gypsum was employed in building construction at locations where wood was previously used.[7]
- A tofu (soy bean curd) coagulant, making it ultimately a major source of dietary calcium, especially in Asian cultures which traditionally use few dairy products.
- Adding hardness to water used for homebrewing.
- Blackboard chalk.
- A component of Portland cement used to prevent flash setting of concrete.
- Soil/water potential monitoring (soil moisture tension)
- A medicinal agent in traditional Chinese medicine called Shi Gao. | https://www.wikidoc.org/index.php/Gypsum |
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