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nfcorpus-corpus-MED-2940 | null | Radiation and chest CT scan examinations: what do we know?
In the past 3 decades, the total number of CT scans performed has grown exponentially. In 2007, > 70 million CT scans were performed in the United States. CT scan studies of the chest comprise a large portion of the CT scans performed today because the technology has transformed the management of common chest diseases, including pulmonary embolism and coronary artery disease. As the number of studies performed yearly increases, a growing fraction of the population is exposed to low-dose ionizing radiation from CT scan. Data extrapolated from atomic bomb survivors and other populations exposed to low-dose ionizing radiation suggest that CT scan-associated radiation may increase an individual's lifetime risk of developing cancer. This finding, however, is not incontrovertible. Because this topic has recently attracted the attention of both the scientific community and the general public, it has become increasingly important for physicians to understand the cancer risk associated with CT scan and be capable of engaging in productive dialogue with patients. This article reviews the current literature on the public health debate surrounding CT scan and cancer risk, quantifies radiation doses associated with specific studies, and describes efforts to reduce population-wide CT scan-associated radiation exposure. CT scan examinations of the chest, including CT scan pulmonary and coronary angiography, high-resolution CT scan, low-dose lung cancer screening, and triple rule-out CT scan, are specifically considered. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2941 | null | Common carotid intima-media thickness is predictive of all-cause and cardiovascular mortality in elderly community-dwelling people: Longitudinal Investigation for the Longevity and Aging in Hokkaido County (LILAC) study
Several cohort studies have examined the association of carotid intima-media thickness (IMT) with the risk of stroke or myocardial infarction in apparently healthy persons. We investigated the predictive value of IMT of cardiovascular mortality in elderly community-dwelling people, beyond the prediction provided by age and MMSE. assessed by means of a multivariate Cox model. Carotid IMT and plaque were evaluated bilaterally with ultrasonography in 298 people older than 75 years ( 120 men and 178 women, average age: 79.6 years). The LILAC study started on July 25, 2000. Consultations were repeated every year. The follow-up ended on November 30, 2004. During the mean follow-up span of 1152 days, 30 subjects (21 men and nine women) died. Nine deaths were attributable to cardiovascular causes Imyocardial infarction: two men and three women; stroke: two men and two women). The age- and MMSE-adjusted relative risk (RR) and 95% confidence interval (95% CI) of developing all-cause mortality was assessed. A 0.3 mm increase in left IMT was associated with a RR of predicted 1.647 (1.075-2.524), and a similar increase in right IMT with a RR of 3.327 (1.429-7.746). For cardiovascular mortality, the corresponding RR values were 2.351 (1.029-5.372) and 2.890 (1.059-7.891), respectively. Carotid IMT assessed by ultrasonography is positively associated with an increased risk of all-cause and cardiovascular death in elderly community-dwelling people. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2942 | null | The impact of vegan diet on B-12 status in healthy omnivores: five-year prospective study.
BACKGROUND: There are no long-term prospective studies assessing the impact of the vegan diet on vitamin B-12 (B-12) status. Many vegans take B-12 supplements irregularly or refuse to adopt them at all, considering them to be "unnatural" products. The use of B-12 fortified food may be an alternative. Therefore, we aimed to estimate the long-term effect of a vegan diet on serum B-12 concentrations in healthy omnivore adults, comparing the influence of natural products consumption and B-12 fortified food. MATERIAL AND METHODS: A five year prospective study was carried out comprising 20 omnivore healthy adult subjects, who moved to strict vegan diet for 5 years. Ten volunteers followed vegan diet based entirely on natural products, while the remaining ten subjects consumed food fortified in B-12. In all subjects serum vitamin B-12 concentration was determined before and 6, 12, 24 and 60 months after the implementation of the diet. RESULTS: A significant decrease (p < 0.0002) of serum B-12 concentrations in the whole studied group was noted after 60 months of vegan diet. However, observed changes were in fact limited to the subgroup consuming exclusively natural products (p < 0.0001). CONCLUSIONS: Transition from omnivore to vegan diet is associated with the risk of vitamin B-12 deficiency. B-12 fortified products might constitute a valuable alternative in vegans refusing to take vitamin supplements. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2943 | null | Long-term low-calorie low-protein vegan diet and endurance exercise are associated with low cardiometabolic risk.
BACKGROUND: Western diets, which typically contain large amounts of energy-dense processed foods, together with a sedentary lifestyle are associated with increased cardiometabolic risk. We evaluated the long-term effects of consuming a low-calorie low-protein vegan diet or performing regular endurance exercise on cardiometabolic risk factors. METHODS: In this cross-sectional study, cardiometabolic risk factors were evaluated in 21 sedentary subjects, who had been on a low-calorie low-protein raw vegan diet for 4.4 +/- 2.8 years, (mean age, 53.1 +/- 11 yrs), 21 body mass index (BMI)-matched endurance runners consuming Western diets, and 21 age- and gender-matched sedentary subjects, consuming Western diets. RESULTS: BMI was lower in the low-calorie low-protein vegan diet (21.3 +/- 3.1 kg/m(2)) and endurance runner (21.1 +/- 1.6 kg/m(2)) groups than in the sedentary Western diet group (26.5 +/- 2.7 kg/m(2)) (p < 0.005). Plasma concentrations of lipids, lipoproteins, glucose, insulin, C-reactive protein, blood pressure (BP), and carotid artery intima-media thickness were lower in the low-calorie low-protein vegan diet and runner groups than in the Western diet group (all p < 0.05). Both systolic and diastolic BP were lower in the low-calorie low-protein vegan diet group (104 +/- 15 and 62 +/- 11 mm Hg) than in BMI-matched endurance runners (122 +/- 13 and 72 +/- 9 mmHg) and Western diet group (132 +/- 14 and 79 +/- 8 mm Hg) (p < 0.001); BP values were directly associated with sodium intake and inversely associated with potassium and fiber intake. CONCLUSIONS: Long-term consumption of a low-calorie low-protein vegan diet or regular endurance exercise training is associated with low cardiometabolic risk. Moreover, our data suggest that specific components of a low-calorie low-protein vegan diet provide additional beneficial effects on blood pressure. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2945 | null | Chinese lacto-vegetarian diet exerts favorable effects on metabolic parameters, intima-media thickness, and cardiovascular risks in healthy men.
BACKGROUND: To investigate whether the Chinese lacto-vegetarian diet has protective effects on metabolic and cardiovascular disease (CVD). METHODS: One hundred sixty-nine healthy Chinese lacto-vegetarians and 126 healthy omnivore men aged 21-76 years were enrolled. Anthropometric indexes, lipid profile, insulin sensitivity, pancreatic β cell function, and intima-media thickness (IMT) of carotid arteries were assessed and compared. Cardiovascular risk points and probability of developing CVD in 5-10 years in participants aged 24-55 years were calculated. RESULTS: Compared with omnivores, lacto-vegetarians had remarkably lower body mass index, systolic and diastolic blood pressure, and serum levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol, apolipoprotein B, γ-glutamyl transferase, serum creatinine, uric acid, fasting blood glucose, as well as lower total cholesterol/high-density lipoprotein cholesterol ratio. Vegetarians also had higher homeostasis model assessment β cell function and insulin secretion index and thinner carotid IMT than the omnivores did. These results corresponded with lower cardiovascular risk points and probability of developing CVD in 5-10 years in vegetarians 24-55 years old. CONCLUSIONS: In healthy Chinese men, the lacto-vegetarian diet seems to exert protective effects on blood pressure, lipid profiles, and metabolic parameters and results in significantly lower carotid IMT. Lower CVD risks found in vegetarians also reflect the beneficial effect of the Chinese lacto-vegetarian diet. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2946 | null | Vitamin B-12 supplementation improves arterial function in vegetarians with subnormal vitamin B-12 status.
OBJECTIVE: Vegetarians are more vascular-healthy but those with subnormal vitamin B-12 status have impaired arterial endothelial function and increased intima-media thickness. We aimed to study the impact of vitamin B-12 supplementation on these markers, in the vegetarians. DESIGN: Double-blind, placebo controlled, randomised crossover study. SETTING: Community dwelling vegetarians. PARTICIPANTS: Fifty healthy vegetarians (vegetarian diet for at least 6 years) were recruited. INTERVENTION: Vitamin B-12 (500 µg/day) or identical placebo were given for 12 weeks with 10 weeks of placebo-washout before crossover (n=43), and then open label vitamin B-12 for additional 24 weeks (n=41). MEASUREMENT: Flow-mediated dilation of brachial artery (FMD) and intima-media thickness (IMT) of carotid artery were measured by ultrasound. RESULTS: The mean age of the subjects was 45±9 years and 22 (44%) were male. Thirty-five subjects (70%) had serum B-12 levels <150 pmol/l. Vitamin B-12 supplementation significantly increased serum vitamin B-12 levels (p<0.0001) and lowered plasma homocysteine (p<0.05). After vitamin B-12 supplementation but not placebo, significant improvement of brachial FMD (6.3±1.8% to 6.9±1.9%; p<0.0001) and in carotid IMT (0.69±0.09 mm to 0.67±0.09 mm, p<0.05) were found, with further improvement in FMD (to 7.4±1.7%; p<0.0001) and IMT (to 0.65±0.09 mm; p<0.001) after 24 weeks open label vitamin B-12. There were no significant changes in blood pressures or lipid profiles. On multivariate analysis, changes in B-12 (β=0.25; p=0.02) but not homocysteine were related to changes in FMD, (R=0.32; F value=3.19; p=0.028). CONCLUSIONS: Vitamin B-12 supplementation improved arterial function in vegetarians with subnormal vitamin B-12 levels, proposing a novel strategy for atherosclerosis prevention. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-2947 | null | Radiation dose from contemporary cardiothoracic multidetector CT protocols with an anthropomorphic female phantom: implications for cancer induction.
PURPOSE: To measure prospectively and directly both organ dose and effective dose (ED) for adult cardiac and pulmonary computed tomographic (CT) angiography by using current clinical protocols for 64-detector CT in an anthropomorphic female phantom and to estimate lifetime attributable risk of breast and lung cancer incidence on the basis of measured ED and organ dose. MATERIALS AND METHODS: Cardiac and pulmonary 64-detector CT angiography was performed by using current clinical protocols to evaluate the pulmonary veins (electrocardiographically [ECG] gated, 64 sections at 0.625-mm collimation, 120 kVp, 300 mA, 0.35-second tube rotation), native coronary arteries (ECG gated; 64 sections at 0.625 mm; 120 kVp; maximum current, 500-750 mA; minimum, 100-350 mA; 0.35-second tube rotation) and pulmonary embolus (64 sections at 1.25 mm, 140 kVp, 645 mA, 0.5-second tube rotation). Absorbed organ doses were measured by using an anthropomorphic female phantom and metal oxide semiconductor field effect transistor detectors. ED was calculated from measured organ doses and the dose-length product. RESULTS: ED for current adult cardiac and pulmonary 64-detector CT angiography protocols were 12.4-31.8 mSv. Overall, skin, breast, and esophagus and heart had the highest recorded absorbed organ doses. Relative risk for breast cancer incidence for girls and women was 1.004-1.042 for a single examination. Relative risk for lung cancer incidence for men and women was 1.005-1.076 from a single examination. CONCLUSION: EDs and organ doses from 64-detector CT are higher than those previously reported for adult cardiac and pulmonary CT angiography protocols. Risk for breast and lung cancer induction from these studies is greatest for the younger patient population. (c) RSNA, 2007. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3270 | null | Protein methionine content and MDA-lysine adducts are inversely related to maximum life span in the heart of mammals.
Aging affects all organisms and its basic mechanisms are expected to be conserved across species. Oxidation of proteins has been proposed to be one of the basic mechanisms linking oxygen radicals with the basic aging process. If oxidative damage to proteins is involved in aging, long-lived animals (which age slowly) should show lower levels of markers of this kind of damage than short-lived ones. However, this possibility has not been investigated yet. In this study, steady-state levels of markers of different kinds of protein damage--oxidation (glutamic and aminoadipic semialdehydes), mixed glyco- and lipoxidation (carboxymethyl- and carboxyethyllysine), lipoxidation (malondialdehydelysine) and amino acid composition--were measured in the heart of eight mammalian species ranging in maximum life span (MLSP) from 3.5 to 46 years. Oxidation markers were directly correlated with MLSP across species. Mixed glyco- and lipoxidation markers did not correlate with MLSP. However, the lipoxidation marker malondialdehydelysine was inversely correlated with MLSP (r2=0.85; P<0.001). The amino acid compositional analysis revealed that methionine is the only amino acid strongly correlated MLSP and that such correlation is negative (r2=0.93; P<0.001). This trait may contribute to lower steady-state levels of oxidized methionine residues in cellular proteins. These results reinforce the notion that high longevity in homeothermic vertebrates is achieved in part by constitutively decreasing the sensitivity of both tissue proteins and lipids to oxidative damage. This is obtained by modifying the constituent structural components of proteins and lipids, selecting those less sensitive to oxidative modifications. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3271 | null | Can dietary methionine restriction increase the effectiveness of chemotherapy in treatment of advanced cancer?
Most metastatic tumors, such as those originating in the prostate, lung, and gastrointestinal tract, respond poorly to conventional chemotherapy. Novel treatment strategies for advanced cancer are therefore desperately needed. Dietary restriction of the essential amino acid methionine offers promise as such a strategy, either alone or in combination with chemotherapy or other treatments. Numerous in vitro and animal studies demonstrate the effectiveness of dietary methionine restriction in inhibiting growth and eventually causing death of cancer cells. In contrast, normal host tissues are relatively resistant to methionine restriction. These preclinical observations led to a phase I clinical trial of dietary methionine restriction for adults with advanced cancer. Preliminary findings from this trial indicate that dietary methionine restriction is safe and feasible for the treatment of patients with advanced cancer. In addition, the trial has yielded some preliminary evidence of antitumor activity. One patient with hormone-independent prostate cancer experienced a 25% reduction in serum prostate-specific antigen (PSA) after 12 weeks on the diet, and a second patient with renal cell cancer experienced an objective radiographic response. The possibility that methionine restriction may act synergistically with other cancer treatments such as chemotherapy is being explored. Findings to date support further investigation of dietary methionine restriction as a novel treatment strategy for advanced cancer. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3272 | null | Colorectal cancer screening with odour material by canine scent detection
Objective Early detection and early treatment are of vital importance to the successful treatment of various cancers. The development of a novel screening method that is as economical and non-invasive as the faecal occult blood test (FOBT) for early detection of colorectal cancer (CRC) is needed. A study was undertaken using canine scent detection to determine whether odour material can become an effective tool in CRC screening. Design Exhaled breath and watery stool samples were obtained from patients with CRC and from healthy controls prior to colonoscopy. Each test group consisted of one sample from a patient with CRC and four control samples from volunteers without cancer. These five samples were randomly and separately placed into five boxes. A Labrador retriever specially trained in scent detection of cancer and a handler cooperated in the tests. The dog first smelled a standard breath sample from a patient with CRC, then smelled each sample station and sat down in front of the station in which a cancer scent was detected. Results 33 and 37 groups of breath and watery stool samples, respectively, were tested. Among patients with CRC and controls, the sensitivity of canine scent detection of breath samples compared with conventional diagnosis by colonoscopy was 0.91 and the specificity was 0.99. The sensitivity of canine scent detection of stool samples was 0.97 and the specificity was 0.99. The accuracy of canine scent detection was high even for early cancer. Canine scent detection was not confounded by current smoking, benign colorectal disease or inflammatory disease. Conclusions This study shows that a specific cancer scent does indeed exist and that cancer-specific chemical compounds may be circulating throughout the body. These odour materials may become effective tools in CRC screening. In the future, studies designed to identify cancer-specific volatile organic compounds will be important for the development of new methods for early detection of CRC. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3273 | null | The low-methionine content of vegan diets may make methionine restriction feasible as a life extension strategy.
Recent studies confirm that dietary methionine restriction increases both mean and maximal lifespan in rats and mice, achieving "aging retardant" effects very similar to those of caloric restriction, including a suppression of mitochondrial superoxide generation. Although voluntary caloric restriction is never likely to gain much popularity as a pro-longevity strategy for humans, it may be more feasible to achieve moderate methionine restriction, in light of the fact that vegan diets tend to be relatively low in this amino acid. Plant proteins - especially those derived from legumes or nuts - tend to be lower in methionine than animal proteins. Furthermore, the total protein content of vegan diets, as a function of calorie content, tends to be lower than that of omnivore diets, and plant protein has somewhat lower bioavailability than animal protein. Whole-food vegan diets that moderate bean and soy intake, while including ample amounts of fruit and wine or beer, can be quite low in methionine, while supplying abundant nutrition for health (assuming concurrent B12 supplementation). Furthermore, low-fat vegan diets, coupled with exercise training, can be expected to promote longevity by decreasing systemic levels of insulin and free IGF-I; the latter effect would be amplified by methionine restriction - though it is not clear whether IGF-I down-regulation is the sole basis for the impact of low-methionine diets on longevity in rodents. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3274 | null | Olfactory detection of human bladder cancer by dogs: proof of principle study
Objective To determine whether dogs can be trained to identify people with bladder cancer on the basis of urine odour more successfully than would be expected by chance alone. Design Experimental, “proof of principle” study in which six dogs were trained to discriminate between urine from patients with bladder cancer and urine from diseased and healthy controls and then evaluated in tests requiring the selection of one bladder cancer urine sample from six controls. Participants 36 male and female patients (age range 48-90 years) presenting with new or recurrent transitional cell carcinoma of the bladder (27 samples used for training; 9 used for formal testing); 108 male and female controls (diseased and healthy, age range 18-85 years—54 samples used in training; 54 used for testing). Main outcome measure Mean proportion of successes per dog achieved during evaluation, compared with an expected value of 1 in 7 (14%). Results Taken as a group, the dogs correctly selected urine from patients with bladder cancer on 22 out of 54 occasions. This gave a mean success rate of 41% (95% confidence intervals 23% to 58% under assumptions of normality, 26% to 52% using bootstrap methods), compared with 14% expected by chance alone. Multivariate analysis suggested that the dogs' capacity to recognise a characteristic bladder cancer odour was independent of other chemical aspects of the urine detectable by urinalysis. Conclusions Dogs can be trained to distinguish patients with bladder cancer on the basis of urine odour more successfully than would be expected by chance alone. This suggests that tumour related volatile compounds are present in urine, imparting a characteristic odour signature distinct from those associated with secondary effects of the tumour, such as bleeding, inflammation, and infection. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3275 | null | The Effect of Replacement of Methionine by Homocystine on Survival of Malignant and Normal Adult Mammalian Cells in Culture
In tissue cultures of normal adult and malignant mammalian cells, homocystine has been substituted for methionine in a medium rich in folic acid and cyanocobalamin. Normal adult cells thrive. Three highly malignant cell types from three different species, including man, die. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3276 | null | A review of methionine dependency and the role of methionine restriction in cancer growth control and life-span extension.
Methionine is an essential amino acid with many key roles in mammalian metabolism such as protein synthesis, methylation of DNA and polyamine synthesis. Restriction of methionine may be an important strategy in cancer growth control particularly in cancers that exhibit dependence on methionine for survival and proliferation. Methionine dependence in cancer may be due to one or a combination of deletions, polymorphisms or alterations in expression of genes in the methionine de novo and salvage pathways. Cancer cells with these defects are unable to regenerate methionine via these pathways. Defects in the metabolism of folate may also contribute to the methionine dependence phenotype in cancer. Selective killing of methionine dependent cancer cells in co-culture with normal cells has been demonstrated using culture media deficient in methionine. Several animal studies utilizing a methionine restricted diet have reported inhibition of cancer growth and extension of a healthy life-span. In humans, vegan diets, which can be low in methionine, may prove to be a useful nutritional strategy in cancer growth control. The development of methioninase which depletes circulating levels of methionine may be another useful strategy in limiting cancer growth. The application of nutritional methionine restriction and methioninase in combination with chemotherapeutic regimens is the current focus of clinical studies. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3277 | null | Expression of the biochemical defect of methionine dependence in fresh patient tumors in primary histoculture.
Methionine dependence is a metabolic defect that occurs in many human tumor cell lines but not normal in unestablished cell strains. Methionine-dependent tumor cell lines are unable to proliferate and arrest in the late S/G2 phase of the cell cycle when methionine is replaced by its immediate precursor homocysteine in the culture medium (MET-HCY+ medium). However, it is not known whether methionine dependence occurs in fresh patient tumors as it does in cell lines. In order to determine whether methionine dependence occurs in fresh patient tumors as well as whether methionine dependence occurs in fresh patient tumors as well as in cell lines we took advantage of the technique of sponge-gel-supported histoculture to grow tumors directly from surgery. We then measured nuclear DNA content by image analysis to determine the cell cycle position in MET-HCY+ compared to MET+HCY- medium in 21 human patient tumors. Human tumor cell lines found to be methionine dependent by cell count were used as positive controls and were found to have marked reduction of cells in G1 compared to total cells in the cell cycle in MET-HCY+ medium with respect to the G1: total cell ratio in MET+HCY- medium. Therefore late cell cycle arrest was used as a marker of methionine dependence for histocultured patient tumors. We found that 5 human tumors of 21, including tumors of the colon, breast, ovary, prostate, and a melanoma, were methionine dependent based on cell cycle analysis. These data on fresh human tumors indicate that methionine dependence may frequently occur in the cancer patient population. Implications for potential therapy based on methionine dependence are discussed. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3278 | null | Sniffer dogs as part of a bimodal bionic research approach to develop a lung cancer screening
Lung cancer (LC) continues to represent a heavy burden for health care systems worldwide. Epidemiological studies predict that its role will increase in the near future. While patient prognosis is strongly associated with tumour stage and early detection of disease, no screening test exists so far. It has been suggested that electronic sensor devices, commonly referred to as ‘electronic noses’, may be applicable to identify cancer-specific volatile organic compounds in the breath of patients and therefore may represent promising screening technologies. However, three decades of research did not bring forward a clinically applicable device. Here, we propose a new research approach by involving specially trained sniffer dogs into research strategies by making use of their ability to identify LC in the breath sample of patients. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3279 | null | Chitin synthesis and degradation as targets for pesticide action.
Various pesticides are being used to destabilize, perturb, or inhibit crucial biochemical and physiological targets related to metabolism, growth, development, nervous communication, or behavior in pestiferous organisms. Chitin is an eukaryotic extracellular aminosugar biopolymer, massively produced by most fungal systems and by invertebrates, notably arthropods. Being an integral supportive component in fungal cell wall, insect cuticle, and nematode egg shell, chitin has been considered as a selective target for pesticide action. Throughout the elaborate processes of chitin formation and deposition, only the polymerization events associated with the cell membrane compartment are so far available for chemical interference. Currently, the actinomycetes-derived nucleoside peptide fungicides such as the polyoxins and the insecticidal benzoylaryl ureas have reached commercial pesticide status. The polyoxins and other structurally-related antibiotics like nikkomycins are strong competitive inhibitors of the polymerizing enzyme chitin synthase. The exact biochemical lesion inflicted by the benzoylaryl ureas is still elusive, but a post-polymerization event, such as translocation of chitin chains across the cell membrane, is suggested. Hydrolytic degradation of the chitin polymer is essential for hyphal growth, branching, and septum formation in fungal systems as well as for the normal molting of arthropods. Recently, insect chitinase activity was strongly and specifically suppressed by allosamidin, an actimomycetes-derived metabolite. In part, the defense mechanism in plants against invasion of pathogens is associated with induced chitinases. Chitin, chitosan, and their oligomers are able to act as elicitors which induce enhanced levels of chitinases in various plants. Lectins which bind to N-acetyl-D-glucosamine strongly interfere with fungal and insect chitin synthases. Plant lectins with similar properties may be involved in plant-pathogen interaction inter alia by suppressing fungal invasion. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3280 | null | Methionine dependency and cancer treatment.
Conventional chemotherapies have showed their limits, notably for patients with advanced cancer. New therapeutic strategies must be identified, and the metabolic abnormalities of cancer cells offer such opportunities. Many human cancer cell lines and primary tumors have absolute requirements for methionine, an essential amino acid. In contrast, normal cells are relatively resistant to exogenous methionine restriction. The biochemical mechanism for methionine dependency has been studied extensively, but the fundamental mechanism remains unclear. A number of investigators have attempted to exploit the methionine dependence of tumors for therapeutic effects in vivo. To reduce in vivo methionine in plasma and tumours, dietary and pharmacological treatments have been used. Methionine-free diet or methionine-deprived total parenteral nutrition causes regression of a variety of animal tumours. Alternatively, methionine depletion was achieved by the use of methioninase. This enzyme specifically degrades methionine and inhibits tumour growth in preclinical models. Because of potential toxicity and quality of life problems, prolonged methionine restriction with diet or with methioninase is not suitable for clinical use. Methionine restriction may find greater application in association with various chemotherapeutic agents. Several preclinical studies have demonstrated synergy between methionine restriction and various cytotoxic chemotherapy drugs. The experimental results accumulated during the last three decades suggest that methionine restriction can become an additional cancer therapeutic strategy, notably in association with chemotherapy. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3281 | null | Targeting methionine auxotrophy in cancer: discovery & exploration.
INTRODUCTION: Amino acid auxotrophy or the metabolic defect which renders cancer incapable of surviving under amino acid depleted conditions is being exploited and explored as a therapeutic against cancer. Early clinical data on asparagine- and arginine-depleting drugs have demonstrated low toxicity and efficacy in melanoma, hepatocellular carcinoma and acute lymphoblastic leukemia. Methionine auxotrophy is a novel niche currently under exploration for targeting certain cancers. AREAS COVERED: In this review we explore the discovery of methionine auxotrophy followed by in vitro, in vivo and patient data on targeting cancer with methionine depletion. We end with a small discussion on bioengineering, pegylation and red blood cell encapsulation as mechanisms for decreasing immunogenicity of methionine-depleting drugs. We hope to provide a platform for future pharmacology, toxicology and cytotoxicity studies with methionine depletion therapy and drugs. EXPERT OPINION: Although methionine auxotrophy seems as a viable target, extensive research addressing normal versus cancer cell toxicity needs to be conducted. Further research also needs to be conducted into the molecular mechanism associated with methionine depletion therapy. Finally, novel methods need to be developed to decrease the immunogenicity of methionine-depleting drugs, a current issue with protein therapeutics. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3282 | null | Generation of gaseous sulfur-containing compounds in tumour tissue and suppression of gas diffusion as an antitumour treatment.
BACKGROUND AND AIMS: The mechanisms of cancer cell growth and metastasis are still not entirely understood, especially from the viewpoint of chemical reactions in tumours. Glycolytic metabolism is markedly accelerated in cancer cells, causing the accumulation of glucose (a reducing sugar) and methionine (an amino acid), which can non-enzymatically react and form carcinogenic substances. There is speculation that this reaction produces gaseous sulfur-containing compounds in tumour tissue. The aims of this study were to clarify the products in tumour and to investigate their effect on tumour proliferation. METHODS: Products formed in the reaction between glucose and methionine or its metabolites were analysed in vitro using gas chromatography. Flatus samples from patients with colon cancer and exhaled air samples from patients with lung cancer were analysed using near-edge x-ray fine adsorption structure spectroscopy and compared with those from healthy individuals. The tumour proliferation rates of mice into which HT29 human colon cancer cells had been implanted were compared with those of mice in which the cancer cells were surrounded by sodium hyaluronate gel to prevent diffusion of gaseous material into the healthy cells. RESULTS: Gaseous sulfur-containing compounds such as methanethiol and hydrogen sulfide were produced when glucose was allowed to react with methionine or its metabolites homocysteine or cysteine. Near-edge x-ray fine adsorption structure spectroscopy showed that the concentrations of sulfur-containing compounds in the samples of flatus from patients with colon cancer and in the samples of exhaled air from patients with lung cancer were significantly higher than in those from healthy individuals. Animal experiments showed that preventing the diffusion of sulfur-containing compounds had a pronounced antitumour effect. CONCLUSIONS: Gaseous sulfur-containing compounds are the main products in tumours and preventing the diffusion of these compounds reduces the tumour proliferation rate, which suggests the possibility of a new approach to cancer treatment. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-3283 | null | Lowered methionine ingestion as responsible for the decrease in rodent mitochondrial oxidative stress in protein and dietary restriction possible i...
Available information indicates that long-lived mammals have low rates of reactive oxygen species (ROS) generation and oxidative damage at their mitochondria. On the other hand, many studies have consistently shown that dietary restriction (DR) in rodents also decreases mitochondrial ROS (mtROS) production and oxidative damage to mitochondrial DNA and proteins. It has been observed that protein restriction also decreases mtROS generation and oxidative stress in rat liver, whereas neither carbohydrate nor lipid restriction change these parameters. This is interesting because protein restriction also increases maximum longevity in rodents (although to a lower extent than DR) and is a much more practicable intervention for humans than DR, whereas neither carbohydrate nor lipid restriction seem to change rodent longevity. Moreover, it has been found that isocaloric methionine restriction also decreases mtROS generation and oxidative stress in rodent tissues, and this manipulation also increases maximum longevity in rats and mice. In addition, excessive dietary methionine also increases mtROS generation in rat liver. These studies suggest that the reduced intake of dietary methionine can be responsible for the decrease in mitochondrial ROS generation and the ensuing oxidative damage that occurs during DR, as well as for part of the increase in maximum longevity induced by this dietary manipulation. In addition, the mean intake of proteins (and thus methionine) of Western human populations is much higher than needed. Therefore, decreasing such levels to the recommended ones has a great potential to lower tissue oxidative stress and to increase healthy life span in humans while avoiding the possible undesirable effects of DR diets. |
nfcorpus-queries-PLAIN-2430 | null | Preventing Brain Loss with B Vitamins? |
nfcorpus-corpus-MED-5322 | null | Characterization of bacteria, clostridia and Bacteroides in faeces of vegetarians using qPCR and PCR-DGGE fingerprinting.
BACKGROUND/AIMS: This study aimed to investigate the quantitative and qualitative changes of bacteria, Bacteroides, Bifidobacterium and Clostridium cluster IV in faecal microbiota associated with a vegetarian diet. METHODS: Bacterial abundances were measured in faecal samples of 15 vegetarians and 14 omnivores using quantitative PCR. Diversity was assessed with PCR-DGGE fingerprinting, principal component analysis (PCA) and Shannon diversity index. RESULTS: Vegetarians had a 12% higher abundance of bacterial DNA than omnivores, a tendency for less Clostridium cluster IV (31.86 +/- 17.00%; 36.64 +/- 14.22%) and higher abundance of Bacteroides (23.93 +/- 10.35%; 21.26 +/- 8.05%), which were not significant due to high interindividual variations. PCA suggested a grouping of bacteria and members of Clostridium cluster IV. Two bands appeared significantly more frequently in omnivores than in vegetarians (p < 0.005 and p < 0.022). One was identified as Faecalibacterium sp. and the other was 97.9% similar to the uncultured gut bacteriumDQ793301. CONCLUSIONS: A vegetarian diet affects the intestinal microbiota, especially by decreasing the amount and changing the diversity of Clostridium cluster IV. It remains to be determined how these shifts might affect the host metabolism and disease risks. Copyright 2009 S. Karger AG, Basel. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5323 | null | Endocrine-disrupting chemicals and obesity development in humans: a review.
This study reviewed the literature on the relations between exposure to chemicals with endocrine-disrupting abilities and obesity in humans. The studies generally indicated that exposure to some of the endocrine-disrupting chemicals was associated with an increase in body size in humans. The results depended on the type of chemical, exposure level, timing of exposure and gender. Nearly all the studies investigating dichlorodiphenyldichloroethylene (DDE) found that exposure was associated with an increase in body size, whereas the results of the studies investigating polychlorinated biphenyl (PCB) exposure were depending on dose, timing and gender. Hexachlorobenzene, polybrominated biphenyls, beta-hexachlorocyclohexane, oxychlordane and phthalates were likewise generally associated with an increase in body size. Studies investigating polychlorinated dibenzodioxins and polychlorinated dibenzofurans found either associations with weight gain or an increase in waist circumference, or no association. The one study investigating relations with bisphenol A found no association. Studies investigating prenatal exposure indicated that exposure in utero may cause permanent physiological changes predisposing to later weight gain. The study findings suggest that some endocrine disruptors may play a role for the development of the obesity epidemic, in addition to the more commonly perceived putative contributors. © 2011 The Authors. obesity reviews © 2011 International Association for the Study of Obesity. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5324 | null | Effects of a high-fat meal on pulmonary function in healthy subjects.
Obesity has important health consequences, including elevating risk for heart disease, diabetes, and cancer. A high-fat diet is known to contribute to obesity. Little is known regarding the effect of a high-fat diet on pulmonary function, despite the dramatic increase in the prevalence of respiratory ailments (e.g., asthma). The purpose of our study was to determine whether a high-fat meal (HFM) would increase airway inflammation and decrease pulmonary function in healthy subjects. Pulmonary function tests (PFT) (forced expiratory volume in 1-s, forced vital capacity, forced expiratory flow at 25-75% of vital capacity) and exhaled nitric oxide (eNO; airway inflammation) were performed in 20 healthy (10 men, 10 women), inactive subjects (age 21.9 +/- 0.4 years) pre and 2 h post HFM (1 g fat/1 kg body weight; 74.2 +/- 4.1 g fat). Total cholesterol, triglycerides, and C-reactive protein (CRP; systemic inflammation) were determined via a venous blood sample pre and post HFM. Body composition was measured via dual energy X-ray absorptiometry. The HFM significantly increased total cholesterol by 4 +/- 1%, and triglycerides by 93 +/- 3%. ENO also increased (p < 0.05) due to the HFM by 19 +/- 1% (pre 17.2 +/- 1.6; post 20.6 +/- 1.7 ppb). ENO and triglycerides were significantly related at baseline and post-HFM (r = 0.82, 0.72 respectively). Despite the increased eNO, PFT or CRP did not change (p > 0.05) with the HFM. These results demonstrate that a HFM, which leads to significant increases in total cholesterol, and especially triglycerides, increases exhaled NO. This suggests that a high-fat diet may contribute to chronic inflammatory diseases of the airway and lung. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5325 | null | Vegetarian diets and blood pressure among white subjects: results from the Adventist Health Study-2 (AHS-2)
Objective Previous work studying vegetarians has often found that they have lower blood pressure (BP). Reasons may include their lower BMI and higher intake levels of fruit and vegetables. Here we seek to extend this evidence in a geographically diverse population containing vegans, lacto-ovo vegetarians and omnivores. Design Data are analysed from a calibration sub-study of the Adventist Health Study-2 (AHS-2) cohort who attended clinics and provided validated FFQ. Criteria were established for vegan, lacto-ovo vegetarian, partial vegetarian and omnivorous dietary patterns. Setting Clinics were conducted at churches across the USA and Canada. Dietary data were gathered by mailed questionnaire. Subjects Five hundred white subjects representing the AHS-2 cohort. Results Covariate-adjusted regression analyses demonstrated that the vegan vegetarians had lower systolic and diastolic BP (mmHg) than omnivorous Adventists (β =−6·8, P<0·05 and β = −6·9, P<0·001). Findings for lacto-ovo vegetarians (β = −9·1, P<0·001 and β = −5·8, P<0·001) were similar. The vegetarians (mainly the vegans) were also less likely to be using antihypertensive medications. Defining hypertension as systolic BP > 139 mmHg or diastolic BP > 89 mmHg or use of antihypertensive medications, the odds ratio of hypertension compared with omnivores was 0·37 (95 % CI 0·19, 0·74), 0·57 (95 % CI 0·36, 0·92) and 0·92 (95 % CI 0·50, 1·70), respectively, for vegans, lacto-ovo vegetarians and partial vegetarians. Effects were reduced after adjustment for BMI. Conclusions We conclude from this relatively large study that vegetarians, especially vegans, with otherwise diverse characteristics but stable diets, do have lower systolic and diastolic BP and less hypertension than omnivores. This is only partly due to their lower body mass. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5326 | null | Red meat and colon cancer: should we become vegetarians, or can we make meat safer?
The effect of meat consumption on cancer risk is a controversial issue. However, recent meta-analyses show that high consumers of cured meats and red meat are at increased risk of colorectal cancer. This increase is significant but modest (20-30%). Current WCRF-AICR recommendations are to eat no more than 500 g per week of red meat, and to avoid processed meat. Moreover, our studies show that beef meat and cured pork meat promote colon carcinogenesis in rats. The major promoter in meat is heme iron, via N-nitrosation or fat peroxidation. Dietary additives can suppress the toxic effects of heme iron. For instance, promotion of colon carcinogenesis in rats by cooked, nitrite-treated and oxidized high-heme cured meat was suppressed by dietary calcium and by α-tocopherol, and a study in volunteers supported these protective effects in humans. These additives, and others still under study, could provide an acceptable way to prevent colorectal cancer. Copyright © 2011 Elsevier B.V. All rights reserved. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5327 | null | The association between dietary patterns and mental health in early adolescence.
OBJECTIVE: To investigate the associations between dietary patterns and mental health in early adolescence. METHOD: The Western Australian Pregnancy Cohort (Raine) Study is a prospective study of 2900 pregnancies recruited from 1989-1992. At 14 years of age (2003-2006; n=1324), the Child Behaviour Checklist (CBCL) was used to assess behaviour (characterising mental health status), with higher scores representing poorer behaviour. Two dietary patterns (Western and Healthy) were identified using factor analysis and food group intakes estimated by a 212-item food frequency questionnaire. Relationships between dietary patterns, food group intakes and behaviour were examined using general linear modelling following adjustment for potential confounding factors at age 14: total energy intake, body mass index, physical activity, screen use, family structure, income and functioning, gender and maternal education at pregnancy. RESULTS: Higher total (b=2.20, 95% CI=1.06, 3.35), internalizing (withdrawn/depressed) (b=1.25, 95% CI=0.15, 2.35) and externalizing (delinquent/aggressive) (b=2.60, 95% CI=1.51, 3.68) CBCL scores were significantly associated with the Western dietary pattern, with increased intakes of takeaway foods, confectionary and red meat. Improved behavioural scores were significantly associated with higher intakes of leafy green vegetables and fresh fruit (components of the Healthy pattern). CONCLUSION: These findings implicate a Western dietary pattern in poorer behavioural outcomes for adolescents. Better behavioural outcomes were associated with a higher intake of fresh fruit and leafy green vegetables. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5328 | null | Vegetarian diets and incidence of diabetes in the Adventist Health Study-2
Aim To evaluate the relationship of diet to incident diabetes among non-Black and Black participants in the Adventist Health Study-2. Methods and Results Participants were 15,200 men and 26,187 women (17.3% Blacks) across the U.S. and Canada who were free of diabetes and who provided demographic, anthropometric, lifestyle and dietary data. Participants were grouped as vegan, lacto ovo vegetarian, pesco vegetarian, semi-vegetarian or non-vegetarian (reference group). A follow-up questionnaire after two years elicited information on the development of diabetes. Cases of diabetes developed in 0.54% of vegans, 1.08% of lacto ovo vegetarians, 1.29% of pesco vegetarians, 0.92% of semi-vegetarians and 2.12% of non-vegetarians. Blacks had an increased risk compared to non-Blacks (odds ratio [OR] 1.364; 95% confidence interval [CI], 1.093–1.702). In multiple logistic regression analysis controlling for age, gender, education, income, television watching, physical activity, sleep, alcohol use, smoking and BMI, vegans (OR 0.381; 95% CI 0.236–0.617), lacto ovo vegetarians (OR 0.618; 95% CI 0.503–0.760) and semi-vegetarians (OR 0.486, 95% CI 0.312–0.755) had a lower risk of diabetes than non-vegetarians. In non-Blacks vegan, lacto ovo and semi-vegetarian diets were protective against diabetes (OR 0.429, 95% CI 0.249–0.740; OR 0.684, 95% CI 0.542–0.862; OR 0.501, 95% CI 0.303–0.827); among Blacks vegan and lacto ovo vegetarian diets were protective (OR 0.304, 95% CI 0.110–0.842; OR 0.472, 95% CI 0.270–0.825). These associations were strengthened when BMI was removed from the analyses. Conclusion Vegetarian diets (vegan, lacto ovo, semi-) were associated with a substantial and independent reduction in diabetes incidence. In Blacks the dimension of the protection associated with vegetarian diets was as great as the excess risk associated with Black ethnicity. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5329 | null | Rapid reduction of serum cholesterol and blood pressure by a twelve-day, very low fat, strictly vegetarian diet.
OBJECTIVE: This study was conducted to demonstrate the effectiveness of a strictly vegetarian, very low-fat diet on cardiac risk factor modification. METHODS: Five hundred men and women, participants in an intensive 12-day live-in program, were studied. The program focused on dietary modification, moderate exercise, and stress management at a hospital-based health-center. RESULTS: During this short time period, cardiac risk factors improved: there was an average reduction of total serum cholesterol of 11% (p < 0.001), of blood pressure of 6% (p < 0.001) and a weight loss of 2.5 kg for men and 1 kg for women. Serum triglycerides did not increase except for two subgroups: females age > or = 65 years with serum cholesterol < 6.5 mmol/L and for females 50 to 64 years with baseline serum cholesterol between 5.2-6.5 mmol/L. High-density lipoprotein cholesterol measured on 66 subjects decreased by 19%. CONCLUSION: A strict, very low-fat vegetarian diet free from all animal products combined with lifestyle changes that include exercise and weight loss is an effective way to lower serum cholesterol and blood pressure. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5330 | null | Effect of a single high-fat meal on endothelial function in healthy subjects.
Although there is a well-established relation between serum cholesterol and coronary artery disease risk, individual and national variations in this association suggest that other factors are involved in atherogenesis. High-fat diet associated triglyceride-rich lipoproteins have also been suggested to be atherogenic. To assess the direct effect of postprandial triglyceride-rich lipoproteins on endothelial function, an early factor in atherogenesis--10 healthy, normocholesterolemic volunteers--were studied before and for 6 hours after single isocaloric high- and low-fat meals (900 calorie; 50 and 0 g fat, respectively). Endothelial function, in the form of flow-mediated vasoactivity, was assessed in the brachial artery using 7.5-MHz ultrasound as percent arterial diameter change 1 minute after 5 minutes of upper-arm arterial occlusion. Serum lipoproteins and glucose were determined before eating and 2 and 4 hours postprandially. Serum triglycerides increased from 94 +/- 55 mg/dl preprandially to 147 +/- 80 mg/dl 2 hours after the high-fat meal (p = 0.05). Flow-dependent vasoactivity decreased from 21 +/- 5% preprandially to 11 +/- 4%, 11 +/- 6%, and 10 +/- 3% at 2, 3, and 4 hours after the high-fat meal, respectively (all p <0.05 compared with low-fat meal data). No changes in lipoproteins or flow-mediated vasoactivity were observed after the low-fat meal. Fasting low-density lipoprotein cholesterol correlated inversely (r = -0.47, p = 0.04) with preprandial flow-mediated vasoactivity, but triglyceride level did not. Mean change in postprandial flow-mediated vasoactivity at 2, 3, and 4 hours correlated with change in 2-hour serum triglycerides (r = -0.51, p = 0.02). These results demonstrate that a single high-fat meal transiently impairs endothelial function. These findings identify a potential process by which a high-fat diet may be atherogenic independent of induced changes in cholesterol. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5331 | null | Influencing public nutrition for non-communicable disease prevention: from community intervention to national programme--experiences from Finland.
A global health transition is currently underway. The burden of non-communicable diseases (NCDs) is increasing rapidly in the developing world, very much as a result of changes in lifestyles. In addition to changes in tobacco use and physical activity, major changes are taking place in diets, contributing greatly to the growing epidemic of NCD. Thus, a huge global public health challenge is how to influence the trends in diet and nutrition for effective global NCD prevention. The health transition took place rapidly in Finland after World War II and mortality from cardiovascular disease (CVD) was exceptionally high. The North Karelia Project was launched in 1972 as a community-based, and later as a national, programme to influence diet and other lifestyles that are crucial in the prevention of CVD. The intervention had a strong theory base and it employed comprehensive strategies. Broad community organisation and the strong participation of people were the key elements. Evaluation has shown how the diet (particularly fat consumption) has changed and how these changes have led to a major reduction in population serum cholesterol and blood pressure levels. It has also shown how ischaemic heart disease mortality in a working-age population has declined by 73% in North Karelia and by 65% in the whole country from 1971 to 1995. Although Finland is an industrialised country, North Karelia was rural, of rather low socio-economic level and with many social problems in the 1970s and 1980s. The project was based on low-cost intervention activities, where people's participation and community organisations played a key role. Comprehensive interventions in the community were eventually supported by national activities--from expert guidelines and media activities to industry collaboration and policy. Similar principles for nutrition intervention programmes could be used in developing countries, obviously tailored to the local conditions. This paper discusses the experiences of the North Karelia Project in the light of needs from the less-industrialised countries and makes some general recommendations. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5332 | null | Quantification of butyryl CoA:acetate CoA-transferase genes reveals different butyrate production capacity in individuals according to diet and age.
The gastrointestinal microbiota produces short-chain fatty acids, especially butyrate, which affect colonic health, immune function and epigenetic regulation. To assess the effects of nutrition and aging on the production of butyrate, the butyryl-CoA:acetate CoA-transferase gene and population shifts of Clostridium clusters lV and XlVa, the main butyrate producers, were analysed. Faecal samples of young healthy omnivores (24 ± 2.5 years), vegetarians (26 ± 5 years) and elderly (86 ± 8 years) omnivores were evaluated. Diet and lifestyle were assessed in questionnaire-based interviews. The elderly had significantly fewer copies of the butyryl-CoA:acetate CoA-transferase gene than young omnivores (P=0.014), while vegetarians showed the highest number of copies (P=0.048). The thermal denaturation of the butyryl-CoA:acetate CoA-transferase gene variant melting curve related to Roseburia/Eubacterium rectale spp. was significantly more variable in the vegetarians than in the elderly. The Clostridium cluster XIVa was more abundant in vegetarians (P=0.049) and in omnivores (P<0.01) than in the elderly group. Gastrointestinal microbiota of the elderly is characterized by decreased butyrate production capacity, reflecting increased risk of degenerative diseases. These results suggest that the butyryl-CoA:acetate CoA-transferase gene is a valuable marker for gastrointestinal microbiota function. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5333 | null | Vegetarian diet affects genes of oxidative metabolism and collagen synthesis.
BACKGROUND/AIM: A vegetarian diet is known to prevent a series of diseases but may influence the balance of carbohydrate and fat metabolism as well as collagen synthesis. This study compares expression patterns of relevant genes in oral mucosa of omnivores and vegetarians. METHODS: Quantitative reverse transcriptase polymerase chain reaction was applied for analysis of mRNA levels from carnitine transporter OCTN2, hepatic CPT1A and nonhepatic CPT1B isoforms of carnitine palmitoyltransferase and collagen (CCOL2A1) in oral mucosa. RESULTS: Compared with volunteers with traditional eating habits, carbohydrate consumption was significantly higher (+22%) in vegetarians. This was associated with a significant stimulation of CPT1A (+50%) and OCTN2 (+10%) and a lowered collagen synthesis (-10%). CONCLUSION: These novel findings provide further insight into the association of a changed fat metabolism and reduced collagen synthesis in vegetarians, which could also play a role in the aging process. Copyright 2008 S. Karger AG, Basel. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5334 | null | Protein-source tryptophan as an efficacious treatment for social anxiety disorder: a pilot study.
Until recently, intact protein that is rich in tryptophan was not seen as an alternative to pharmaceutical-grade tryptophan because protein also contains large neutral amino acids (LNAAs) that compete for transport sites across the blood-brain barrier. Recent evidence indicates that when deoiled gourd seed (a rich source of tryptophan with approximately 22 mg/g protein) is combined with glucose (a carbohydrate that reduces serum levels of competing LNAAs) a clinical effect similar to that of pharmaceutical-grade tryptophan is achieved. Objective and subjective measures of anxiety in those suffering from social phobia (also known as social anxiety disorder) were employed to measure changes in anxiety in response to a stimulus as part of a double-blind, placebo-controlled, crossover study with a wash-out period of 1 week between study sessions. Subjects were randomly assigned to start with either (i) protein-source tryptophan (deoiled gourd seed) in combination with carbohydrate or (ii) carbohydrate alone. One week after the initial session, subjects returned for a follow-up session and received the opposite treatment of that received at the first session. All 7 subjects who began the study completed the 2-week protocol. Protein-source tryptophan with carbohydrate, but not carbohydrate alone, resulted in significant improvement on an objective measure of anxiety. Protein-source tryptophan combined with a high glycemic carbohydrate is a potential anxiolytic to those suffering from social phobia. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5335 | null | Does a vegan diet reduce risk for Parkinson's disease?
Three recent case-control studies conclude that diets high in animal fat or cholesterol are associated with a substantial increase in risk for Parkinson's disease (PD); in contrast, fat of plant origin does not appear to increase risk. Whereas reported age-adjusted prevalence rates of PD tend to be relatively uniform throughout Europe and the Americas, sub-Saharan black Africans, rural Chinese, and Japanese, groups whose diets tend to be vegan or quasi-vegan, appear to enjoy substantially lower rates. Since current PD prevalence in African-Americans is little different from that in whites, environmental factors are likely to be responsible for the low PD risk in black Africans. In aggregate, these findings suggest that vegan diets may be notably protective with respect to PD. However, they offer no insight into whether saturated fat, compounds associated with animal fat, animal protein, or the integrated impact of the components of animal products mediates the risk associated with animal fat consumption. Caloric restriction has recently been shown to protect the central dopaminergic neurons of mice from neurotoxins, at least in part by induction of heat-shock proteins; conceivably, the protection afforded by vegan diets reflects a similar mechanism. The possibility that vegan diets could be therapeutically beneficial in PD, by slowing the loss of surviving dopaminergic neurons, thus retarding progression of the syndrome, may merit examination. Vegan diets could also be helpful to PD patients by promoting vascular health and aiding blood-brain barrier transport of L-dopa. Copyright 2001 Harcourt Publishers Ltd. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5363 | null | Dietary patterns and depressive symptoms among Japanese men and women.
OBJECTIVE: Although several studies have reported associations of depressive state with specific nutrients and foods, few studies examined the association with dietary patterns in adults. We investigated the association between major dietary patterns and depressive symptoms in Japanese. METHODS: Subjects were 521 municipal employees (309 men and 212 women), aged 21-67 years, who participated in a health survey at the time of periodic checkup. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) Scale. Dietary patterns were derived by using principal component analysis of the consumption of 52 food and beverage items, which was assessed by a validated brief diet history questionnaire. Logistic regression analysis was used to estimate odds ratios of depressive symptoms (CES-D >or=16) with adjustment for potential confounding variables. RESULTS: We identified three dietary patterns. A healthy Japanese dietary pattern characterized by high intakes of vegetables, fruit, mushrooms and soy products was associated with fewer depressive symptoms. The multivariate-adjusted odds ratios (95% confidence intervals) of having depressive symptoms for the lowest through highest tertiles of the healthy Japanese dietary pattern score were 1.00 (reference), 0.99 (0.62-1.59) and 0.44 (0.25-0.78), respectively (P for trend=0.006). Other dietary patterns were not appreciably associated with depressive symptoms. CONCLUSIONS: Our findings suggest that a healthy Japanese dietary pattern may be related to decreased prevalence of depressive status. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5337 | null | Intensive lifestyle changes may affect the progression of prostate cancer.
PURPOSE: Men with prostate cancer are often advised to make changes in diet and lifestyle, although the impact of these changes has not been well documented. Therefore, we evaluated the effects of comprehensive lifestyle changes on prostate specific antigen (PSA), treatment trends and serum stimulated LNCaP cell growth in men with early, biopsy proven prostate cancer after 1 year. MATERIALS AND METHODS: Patient recruitment was limited to men who had chosen not to undergo any conventional treatment, which provided an unusual opportunity to have a nonintervention randomized control group to avoid the confounding effects of interventions such as radiation, surgery or androgen deprivation therapy. A total of 93 volunteers with serum PSA 4 to 10 ng/ml and cancer Gleason scores less than 7 were randomly assigned to an experimental group that was asked to make comprehensive lifestyle changes or to a usual care control group. RESULTS: None of the experimental group patients but 6 control patients underwent conventional treatment due to an increase in PSA and/or progression of disease on magnetic resonance imaging. PSA decreased 4% in the experimental group but increased 6% in the control group (p = 0.016). The growth of LNCaP prostate cancer cells (American Type Culture Collection, Manassas, Virginia) was inhibited almost 8 times more by serum from the experimental than from the control group (70% vs 9%, p <0.001). Changes in serum PSA and also in LNCaP cell growth were significantly associated with the degree of change in diet and lifestyle. CONCLUSIONS: Intensive lifestyle changes may affect the progression of early, low grade prostate cancer in men. Further studies and longer term followup are warranted. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5338 | null | Original Articles: Vegetarian Compared with Meat Dietary Protein Source and Phosphorus Homeostasis in Chronic Kidney Disease
Summary Background and objectives Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia induced by increases in fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). This provides the rationale for recommendations to restrict dietary phosphate intake to 800 mg/d. However, the protein source of the phosphate may also be important. Design, setting, participants, & measurements We conducted a crossover trial in nine patients with a mean estimated GFR of 32 ml/min to directly compare vegetarian and meat diets with equivalent nutrients prepared by clinical research staff. During the last 24 hours of each 7-day diet period, subjects were hospitalized in a research center and urine and blood were frequently monitored. Results The results indicated that 1 week of a vegetarian diet led to lower serum phosphorus levels and decreased FGF23 levels. The inpatient stay demonstrated similar diurnal variation for blood phosphorus, calcium, PTH, and urine fractional excretion of phosphorus but significant differences between the vegetarian and meat diets. Finally, the 24-hour fractional excretion of phosphorus was highly correlated to a 2-hour fasting urine collection for the vegetarian diet but not the meat diet. Conclusions In summary, this study demonstrates that the source of protein has a significant effect on phosphorus homeostasis in patients with CKD. Therefore, dietary counseling of patients with CKD must include information on not only the amount of phosphate but also the source of protein from which the phosphate derives. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5339 | null | Is Escherichia coli urinary tract infection a zoonosis? Proof of direct link with production animals and meat.
Recently, it has been suggested that the Escherichia coli causing urinary tract infection (UTI) may come from meat and animals. The purpose was to investigate if a clonal link existed between E. coli from animals, meat and UTI patients. Twenty-two geographically and temporally matched B2 E. coli from UTI patients, community-dwelling humans, broiler chicken meat, pork, and broiler chicken, previously identified to exhibit eight virulence genotypes by microarray-detection of approximately 300 genes, were investigated for clonal relatedness by PFGE. Nine isolates were selected and tested for in vivo virulence in the mouse model of ascending UTI. UTI and community-dwelling human strains were closely clonally related to meat strains. Several human derived strains were also clonally interrelated. All nine isolates regardless of origin were virulent in the UTI model with positive urine, bladder and kidney cultures. Further, isolates with the same gene profile also yielded similar bacterial counts in urine, bladder and kidneys. This study showed a clonal link between E. coli from meat and humans, providing solid evidence that UTI is zoonosis. The close relationship between community-dwelling human and UTI isolates may indicate a point source spread, e.g. through contaminated meat. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5340 | null | Renal function parameters of Thai vegans compared with non-vegans.
In Asia, vegetarianism is a well-established eating behavior. It appears that the adoption of a vegan diet leads to a lessening of several health risk factors. Although vegetarianism has some notable effects on the hematological system, the effect on the nephrological system has not been well clarified. The pattern of renal function parameters was studied in 25 Thai vegans compared with 25 non-vegetarians. Of the studied parameters, it was found that urine protein was significantly different (p < 0.05) in vegans and controls. Vegans had significantly lower urine protein level. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5341 | null | Effects of a low-fat, high-fiber diet and exercise program on breast cancer risk factors in vivo and tumor cell growth and apoptosis in vitro.
The present study investigated the effects of a diet and exercise intervention on known breast cancer (BCa) risk factors, including estrogen, obesity, insulin, and insulin-like growth factor-I (IGF-I), in overweight/obese, postmenopausal women. In addition, using the subjects' pre- and postintervention serum in vitro, serum-stimulated growth and apoptosis of three estrogen receptor-positive BCa cell lines were studied. The women where placed on a low-fat (10-15% kcal), high-fiber (30-40 g per 1,000 kcal/day) diet and attended daily exercise classes for 2 wk. Serum estradiol was reduced in the women on hormone treatment (HT; n = 28) as well as those not on HT (n = 10). Serum insulin and IGF-I were significantly reduced in all women, whereas IGF binding protein-1 was increased significantly. In vitro growth of the BCa cell lines was reduced by 6.6% for the MCF-7 cells, 9.9% for the ZR-75-1 cells, and 18.5% for the T-47D cells. Apoptosis was increased by 20% in the ZR-75-1 cells, 23% in the MCF-7 cells, and 30% in the T-47D cells (n = 12). These results show that a very-low-fat, high-fiber diet combined with daily exercise results in major reductions in risk factors for BCa while subjects remained overweight/obese. These in vivo serum changes slowed the growth and induced apoptosis in serum-stimulated BCa cell lines in vitro. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-5342 | null | Vegetarian diets are associated with healthy mood states: a cross-sectional study in Seventh Day Adventist adults
Background The physical health status of vegetarians has been extensively reported, but there is limited research regarding the mental health status of vegetarians, particularly with regard to mood. Vegetarian diets exclude fish, the major dietary source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), critical regulators of brain cell structure and function. Omnivorous diets low in EPA and DHA are linked to impaired mood states in observational and experimental studies. Methods We examined associations between mood state and polyunsaturated fatty acid intake as a result of adherence to a vegetarian or omnivorous diet in a cross-sectional study of 138 healthy Seventh Day Adventist men and women residing in the Southwest. Participants completed a quantitative food frequency questionnaire, Depression Anxiety Stress Scale (DASS), and Profile of Mood States (POMS) questionnaires. Results Vegetarians (VEG:n = 60) reported significantly less negative emotion than omnivores (OMN:n = 78) as measured by both mean total DASS and POMS scores (8.32 ± 0.88 vs 17.51 ± 1.88, p = .000 and 0.10 ± 1.99 vs 15.33 ± 3.10, p = .007, respectively). VEG reported significantly lower mean intakes of EPA (p < .001), DHA (p < .001), as well as the omega-6 fatty acid, arachidonic acid (AA; p < .001), and reported higher mean intakes of shorter-chain α-linolenic acid (p < .001) and linoleic acid (p < .001) than OMN. Mean total DASS and POMS scores were positively related to mean intakes of EPA (p < 0.05), DHA (p < 0.05), and AA (p < 0.05), and inversely related to intakes of ALA (p < 0.05), and LA (p < 0.05), indicating that participants with low intakes of EPA, DHA, and AA and high intakes of ALA and LA had better mood. Conclusions The vegetarian diet profile does not appear to adversely affect mood despite low intake of long-chain omega-3 fatty acids. |
nfcorpus-queries-PLAIN-2440 | null | More Than an Apple a Day: Combating Common Diseases |
nfcorpus-corpus-MED-1166 | null | Prenatal Exposure to Organophosphate Pesticides and IQ in 7-Year-Old Children
Context: Organophosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely affect children’s cognitive development. Objective: We examined associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children. Methods: We conducted a birth cohort study (Center for the Health Assessment of Mothers and Children of Salinas study) among predominantly Latino farmworker families from an agricultural community in California. We assessed exposure to OP pesticides by measuring dialkyl phosphate (DAP) metabolites in urine collected during pregnancy and from children at 6 months and 1, 2, 3.5, and 5 years of age. We administered the Wechsler Intelligence Scale for Children, 4th edition, to 329 children 7 years of age. Analyses were adjusted for maternal education and intelligence, Home Observation for Measurement of the Environment score, and language of cognitive assessment. Results: Urinary DAP concentrations measured during the first and second half of pregnancy had similar relations to cognitive scores, so we used the average of concentrations measured during pregnancy in further analyses. Averaged maternal DAP concentrations were associated with poorer scores for Working Memory, Processing Speed, Verbal Comprehension, Perceptual Reasoning, and Full-Scale intelligence quotient (IQ). Children in the highest quintile of maternal DAP concentrations had an average deficit of 7.0 IQ points compared with those in the lowest quintile. However, children’s urinary DAP concentrations were not consistently associated with cognitive scores. Conclusions: Prenatal but not postnatal urinary DAP concentrations were associated with poorer intellectual development in 7-year-old children. Maternal urinary DAP concentrations in the present study were higher but nonetheless within the range of levels measured in the general U.S. population. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1167 | null | Pesticides and human chronic diseases: evidences, mechanisms, and perspectives.
Along with the wide use of pesticides in the world, the concerns over their health impacts are rapidly growing. There is a huge body of evidence on the relation between exposure to pesticides and elevated rate of chronic diseases such as different types of cancers, diabetes, neurodegenerative disorders like Parkinson, Alzheimer, and amyotrophic lateral sclerosis (ALS), birth defects, and reproductive disorders. There is also circumstantial evidence on the association of exposure to pesticides with some other chronic diseases like respiratory problems, particularly asthma and chronic obstructive pulmonary disease (COPD), cardiovascular disease such as atherosclerosis and coronary artery disease, chronic nephropathies, autoimmune diseases like systemic lupus erythematous and rheumatoid arthritis, chronic fatigue syndrome, and aging. The common feature of chronic disorders is a disturbance in cellular homeostasis, which can be induced via pesticides' primary action like perturbation of ion channels, enzymes, receptors, etc., or can as well be mediated via pathways other than the main mechanism. In this review, we present the highlighted evidence on the association of pesticide's exposure with the incidence of chronic diseases and introduce genetic damages, epigenetic modifications, endocrine disruption, mitochondrial dysfunction, oxidative stress, endoplasmic reticulum stress and unfolded protein response (UPR), impairment of ubiquitin proteasome system, and defective autophagy as the effective mechanisms of action. Copyright © 2013 Elsevier Inc. All rights reserved. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1178 | null | Are organic foods safer or healthier than conventional alternatives?: a systematic review.
BACKGROUND: The health benefits of organic foods are unclear. PURPOSE: To review evidence comparing the health effects of organic and conventional foods. DATA SOURCES: MEDLINE (January 1966 to May 2011), EMBASE, CAB Direct, Agricola, TOXNET, Cochrane Library (January 1966 to May 2009), and bibliographies of retrieved articles. STUDY SELECTION: English-language reports of comparisons of organically and conventionally grown food or of populations consuming these foods. DATA EXTRACTION: 2 independent investigators extracted data on methods, health outcomes, and nutrient and contaminant levels. DATA SYNTHESIS: 17 studies in humans and 223 studies of nutrient and contaminant levels in foods met inclusion criteria. Only 3 of the human studies examined clinical outcomes, finding no significant differences between populations by food type for allergic outcomes (eczema, wheeze, atopic sensitization) or symptomatic Campylobacter infection. Two studies reported significantly lower urinary pesticide levels among children consuming organic versus conventional diets, but studies of biomarker and nutrient levels in serum, urine, breast milk, and semen in adults did not identify clinically meaningful differences. All estimates of differences in nutrient and contaminant levels in foods were highly heterogeneous except for the estimate for phosphorus; phosphorus levels were significantly higher than in conventional produce, although this difference is not clinically significant. The risk for contamination with detectable pesticide residues was lower among organic than conventional produce (risk difference, 30% [CI, -37% to -23%]), but differences in risk for exceeding maximum allowed limits were small. Escherichia coli contamination risk did not differ between organic and conventional produce. Bacterial contamination of retail chicken and pork was common but unrelated to farming method. However, the risk for isolating bacteria resistant to 3 or more antibiotics was higher in conventional than in organic chicken and pork (risk difference, 33% [CI, 21% to 45%]). LIMITATION: Studies were heterogeneous and limited in number, and publication bias may be present. CONCLUSION: The published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods. Consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria. PRIMARY FUNDING SOURCE: None. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1169 | null | Reduction in urinary organophosphate pesticide metabolites in adults after a week-long organic diet.
BACKGROUND: Conventional food production commonly uses organophosphate (OP) pesticides, which can have negative health effects, while organic food is deemed healthier because it is produced without these pesticides. Studies suggest that organic food consumption may significantly reduce OP pesticide exposure in children who have relatively higher pesticide exposure than adults due to their different diets, body weight, behaviour and less efficient metabolism. OBJECTIVES: A prospective, randomised, crossover study was conducted to determine if an organic food diet reduces organophosphate exposure in adults. METHODS: Thirteen participants were randomly allocated to consume a diet of at least 80% organic or conventional food for 7 days and then crossed over to the alternate diet. Urinary levels of six dialkylphosphate metabolites were analysed in first-morning voids collected on day 8 of each phase using GC-MS/MS with detection limits of 0.11-0.51 μg/L. RESULTS: The mean total DAP results in the organic phase were 89% lower than in the conventional phase (M=0.032 [SD=0.038] and 0.294 [SD=0.435] respectively, p=0.013). For total dimethyl DAPs there was a 96% reduction (M=0.011 [SD=0.023] and 0.252 [SD=0.403] respectively, p=0.005). Mean total diethyl DAP levels in the organic phase were half those of the conventional phase (M=0.021 [SD=0.020] and 0.042 [SD=0.038] respectively), yet the wide variability and small sample size meant the difference was not statistically significant. CONCLUSIONS: The consumption of an organic diet for one week significantly reduced OP pesticide exposure in adults. Larger scale studies in different populations are required to confirm these findings and investigate their clinical relevance. Copyright © 2014 Elsevier Inc. All rights reserved. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1170 | null | Parental occupational exposure to pesticides as risk factor for brain tumors in children and young adults: a systematic review and meta-analysis.
OBJECTIVE: To examine the potential association between parental occupational exposure to pesticides and the occurrence of brain tumors in children and young adults. METHODS: Studies identified from a MEDLINE search through 15 January 2013 and from the reference lists of identified publications were submitted to a systematic review and meta-analysis. Relative risk estimates were extracted from 20 studies published between 1974 and 2010. Most of the retrieved studies involved farm/agricultural jobs. Summary ratio estimates (SR) were calculated according to fixed and random-effect meta-analysis models. Separate analyses were conducted after stratification for study design, exposure parameters, disease definition, geographic location and age at diagnosis. RESULTS: Statistically significant associations were observed for parents potentially exposed to pesticides in occupational settings and the occurrence of brain tumor in their offspring after combining all case-control studies (summary odds ratio [SOR]: 1.30; 95%: 1.11, 1.53) or all cohort studies (summary rate ratio [SRR]: 1.53; 95% CI: 1.20, 1.95). Significantly increased risks were seen for prenatal exposure windows, for either exposed parent, for exposure defined as to pesticides as well as by occupational/industry title, for astroglial brain tumors and after combining case-control studies from North America or cohort studies from Europe. CONCLUSIONS: This meta-analysis supports an association between parental occupational exposure to pesticides and brain tumors in children and young adults, and adds to the evidence leading to the recommendation of minimizing (parental) occupational exposure to pesticides. These results must, however, be interpreted with caution because the impact of work-related factors others than pesticide exposure is not known. Copyright © 2013 Elsevier Ltd. All rights reserved. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1171 | null | Chemical exposure early in life and the neurodevelopment of children--an overview of current epidemiological evidence.
A number of chemicals have been shown to demonstrate neurotoxic effects either in human or laboratory animal studies. This article aims at evaluating the impact of exposure to several chemicals including: organophosphate, organochlorine pesticides, polychlorinated biphenyls (PCBs), mercury and lead on the neurodevelopment of children by reviewing the most recent published literature, and answer the question whether any progress has been made in the epidemiology of the neurodevelopment of children induced by exposure to those chemicals. The result of the presented studies show that exposure to the above-mentioned chemicals may impair the neurodevelopment of children. Neonates exposed to organophosphate pesticides demonstrated a higher proportion of abnormal reflexes, and young children had more attention problems. Exposure to organochlorine pesticides in children was associated with alertness, quality of alert responsiveness, cost of attention and other potential attention associated measures. The majority of studies indicate the negative impact of lead exposure at the level <10 µg/dl or even <5 µg/dl on the neurodevelopment of children. The results of studies on exposure to PCBs, mercury, and their effect on neurodevelopment are inconsistent. Some suggest that prenatal exposure to PCBs and mercury is related to performance impairments, attention and concentration problems, while other do not present any statistically significant association. The studies were mostly well designed, using prospective cohorts with the exposure assessment based on the biomarker of exposure. Concerning the covariates and confounders affecting the endpoints in most of the presented studies, confounders were included in data analysis. In order to recognize the early cognitive, motor and language outcomes of chemical exposures, well standardized tools were used for evaluating the neurodevelopmental effects and offer an early and fairly comprehensive measure of child development. Because the neurotoxicants may cross the placenta and the fetal brain, exposure consideration regarding the reduction of exposure to those chemicals should be implemented. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1172 | null | Dietary Intake and Its Contribution to Longitudinal Organophosphorus Pesticide Exposure in Urban/Suburban Children
Background The widespread use of organophosphorus (OP) pesticides has led to frequent exposure in adults and children. Because such exposure may cause adverse health effects, particularly in children, the sources and patterns of exposure need to be studied further. Objectives We assessed young urban/suburban children’s longitudinal exposure to OP pesticides in the Children’s Pesticide Exposure Study (CPES) conducted in the greater Seattle, Washington, area, and used a novel study design that allowed us to determine the contribution of dietary intake to the overall OP pesticide exposure. Methods Twenty-three children 3–11 years of age who consumed only conventional diets were recruited for this 1-year study conducted in 2003–2004. Children switched to organic diets for 5 consecutive days in the summer and fall sampling seasons. We measured specific urinary metabolites for malathion, chlorpyrifos, and other OP pesticides in urine samples collected twice daily for a period of 7, 12, or 15 consecutive days during each of the four seasons. Results By substituting organic fresh fruits and vegetables for corresponding conventional food items, the median urinary metabolite concentrations were reduced to nondetected or close to non-detected levels for malathion and chlorpyrifos at the end of the 5-day organic diet intervention period in both summer and fall seasons. We also observed a seasonal effect on the OP urinary metabolite concentrations, and this seasonality corresponds to the consumption of fresh produce throughout the year. Conclusions The findings from this study demonstrate that dietary intake of OP pesticides represents the major source of exposure in young children. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
nfcorpus-corpus-MED-1173 | null | Choice of organic foods is related to perceived consequences for human health and to environmentally friendly behaviour.
We designed a questionnaire concerned with attitudes and behaviour towards organic foods, environmentally friendly behaviour (EFB), and perceived consequences of organic food choice in terms of human health, the environment and animal welfare. It was mailed in 1998 to a random nation-wide sample of 2000 Swedish citizens, ages 18-65 years, and 1154 (58%) responded. Self-reported purchase of organic foods was most strongly related to perceived benefit for human health. Performance of EFBs such as refraining from car driving was also a good predictor of purchase frequency. The results indicate that egoistic motives are better predictors of the purchase of organic foods than are altruistic motives. |
nfcorpus-queries-PLAIN-2450 | null | Are Organic Foods Safer? |
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