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nfcorpus-qrel-MED-2149 | Generate text that best answers this question: caloric restriction | Legume intake is inversely associated with metabolic syndrome in adults.
BACKGROUND: Studies on the association between legume intake and metabolic syndrome (MetS) are sparse. The objective of this study is to evaluate the association between legume intake, MetS, and its components. METHODS: This study was conducted on 80 subjects (48% female) with MetS as cases and 160 age and gender-matched healthy controls. Anthropometric measures, blood pressure, fasting blood glucose, and lipid profiles were evaluated by standard methods. Dietary data were collected using a food frequency questionnaire (FFQ) and legume intake was determined. MetS was defined according to the definition of the Adult Treatment Panel III. RESULTS: The mean (SD) intake of legumes was 1.4 (0.9) servings/week for cases and 2.3 (1.1) servings/week for control subjects (P < 0.05). After adjustment for potential confounders, decreases in mean systolic blood pressure, fasting blood glucose, and increase in HDL cholesterol levels were observed across increasing quartile categories of legume intake. After adjustments for life style and food groups, subjects in the highest quartile of legume intake had lower odds of having MetS compared with those in the lowest quartile [odds ratio (OR): 0.25; 95% CI: 0.11 - 0.64, P < 0.05], an association that weakened after adjustment for body mass index (BMI), but remained significant (OR: 0.28; 95% CI: 0.12 - 0.81, P < 0.05). CONCLUSIONS: Legume intake is inversely associated with the risk of having MetS and some of its components. |
nfcorpus-qrel-MED-2324 | Generate text that best answers this question: caloric restriction | The role of hormesis in life extension by dietary restriction.
The level of food restriction that results in life extension and retarded aging in rodents also enhances their ability to cope with intense stressors. Moreover, this level of dietary restriction (DR) leads to a modest increase in the daily peak concentration of plasma free corticosterone, which strongly points to DR as a low-intensity stressor. These findings suggest that hormesis plays a role in the life-extending and anti-aging actions of DR. The evidence for and against this possibility is considered, and it is concluded that hormesis does have an important role. |
nfcorpus-qrel-MED-2325 | Generate text that best answers this question: caloric restriction | Longevity. The allostatic load of dietary restriction.
Restriction of food intake by 10-50% of ad libitum on a per unit of weight or energy content basis can extend the lifespan of a wide variety of species and prevent or delay age-related disease. This review first briefly summarizes the data delineating mortality trajectories of various species' populations maintained on restricted diets to provide insight into the effects of nutrient deprivation on distinct components of the aging process. Next, I discuss a number of important studies that have addressed the question whether it is the lack of calories and/or specific nutrients that determines the longevity response to dietary restriction. Finally, I review the evidence for hormesis as a proximate mechanism underpinning the impact of dietary restriction on lifespan. In aggregate, the currently available demographic data suggest that dietary restriction can both slow the age-related progressive accumulation of cellular damage and also enhance the ability of organisms to cope with irreversible injury. Restriction of essential nutrients as well as calories may affect life expectancy, perhaps in a species specific fashion. Hormesis, i.e. an evolutionary conserved stress response routine providing protection against a wide variety of (other) hazards in response to low levels of stress, is very likely to contribute to the beneficial health effects of dietary restriction. Copyright © 2011 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-2326 | Generate text that best answers this question: caloric restriction | Methionine as methyl-group donor in the synthesis of Mycobacterium avium envelope lipids, and its inhibition by DL-ethionine, D-norleucine and DL-n...
The radioactivity from 3H-methyl methionine was rapidly incorporated into the surface lipids of Mycobacterium avium. The transmethylation reaction was efficiently inhibited by DL-ethionine, D-norleucine and DL-norleucine. The structure of the outerlayer of the M. avium envelope was profoundly altered in the bacteria treated with DL-norleucine. |
nfcorpus-qrel-MED-2327 | Generate text that best answers this question: caloric restriction | Xenohormesis mechanisms underlying chemopreventive effects of some dietary phytochemicals.
A wide variety of phytochemicals present in our diet, including fruits, vegetables, and spices, have been shown to possess a broad range of health-beneficial properties. The cytoprotective and restorative effects of dietary phytochemicals are likely to result from the modulation of several distinct cellular signal transduction pathways. Many dietary phytochemicals that are synthesized as secondary metabolites function as toxins, that is, "phytoalexins," and hence protect plants against insects and other damaging organisms and stresses. However, at the relatively low doses consumed by humans and other mammals, these same toxic plant-derived chemicals, as mild stressors, activate adaptive cellular response signaling, conferring stress resistance and other health benefits. This phenomenon has been referred to as xenohormesis. This review highlights the xenohormesis mechanisms underlying chemopreventive effects of some dietary chemopreventive phytochemicals, with special focus on the nuclear transcription factor erythroid 2p45 (NF-E2)-related factor 2 (Nrf2) as a key player. © 2011 New York Academy of Sciences. |
nfcorpus-qrel-MED-2328 | Generate text that best answers this question: caloric restriction | Treating aging: progress toward dietary restriction mimetics
During the last decade, biogerontologists have labored to understand the biological basis of the aging process by studying the genes and signaling pathways that regulate it. But the last year has seen a breakthrough in a different direction: toward treatments that might slow aging by mimicking the effects of dietary restriction. |
nfcorpus-qrel-MED-2335 | Generate text that best answers this question: caloric restriction | Xenohormesis: health benefits from an eon of plant stress response evolution
Xenohormesis is a biological principle that explains how environmentally stressed plants produce bioactive compounds that can confer stress resistance and survival benefits to animals that consume them. Animals can piggyback off products of plants' sophisticated stress response which has evolved as a result of their stationary lifestyle. Factors eliciting the plant stress response can judiciously be employed to maximize yield of health-promoting plant compounds. The xenohormetic plant compounds can, when ingested, improve longevity and fitness by activating the animal's cellular stress response and can be applied in drug discovery, drug production, and nutritional enhancement of diet. |
nfcorpus-qrel-MED-2330 | Generate text that best answers this question: caloric restriction | Hormesis Defined
Hormesis is a term used by toxicologists to refer to a biphasic dose response to an environmental agent characterized by a low dose stimulation or beneficial effect and a high dose inhibitory or toxic effect. In the fields of biology and medicine hormesis is defined as an adaptive response of cells and organisms to a moderate (usually intermittent) stress. Examples include ischemic preconditioning, exercise, dietary energy restriction and exposures to low doses of certain phytochemicals. Recent findings have elucidated the cellular signaling pathways and molecular mechanisms that mediate hormetic responses which typically involve enzymes such as kinases and deacetylases, and transcription factors such as Nrf-2 and NF-κB. As a result, cells increase their production of cytoprotective and restorative proteins including growth factors, phase 2 and antioxidant enzymes, and protein chaperones. A better understanding of hormesis mechanisms at the cellular and molecular levels is leading to and to novel approaches for the prevention and treatment of many different diseases. |
nfcorpus-qrel-MED-2331 | Generate text that best answers this question: caloric restriction | Xenohormesis: Sensing the Chemical Cues of Other Species
Many plant molecules interact with and modulate key regulators of mammalian physiology in ways that are beneficial to health, but why? We propose that heterotrophs (animals and fungi) are able to sense chemical cues synthesized by plants and other autotrophs in response to stress. These cues provide advance warning about deteriorating environmental conditions, allowing the heterotrophs to prepare for adversity while conditions are still favorable. |
nfcorpus-qrel-MED-2441 | Generate text that best answers this question: caloric restriction | Vegetarian diet ameliorates symptoms of atopic dermatitis through reduction of the number of peripheral eosinophils and of PGE2 synthesis by monocy...
Many patients with atopic dermatitis are dissatisfied with conventional treatments based on topical steroids and have experienced some traditional remedies and alternative therapies. However, most of such therapies have not been evaluated scientifically and clinically by specialists. This study was designed to assess whether a certain vegetarian diet might be effective for atopic dermatitis and if so, to identify the mechanisms of this remedy through analyses of immunological parameters. An open-trial study was carried out in twenty patients with atopic dermatitis. An improvement of dermatitis was evaluated by SCORAD index and serological and immunological parameters were monitored. After a two-month treatment, the severity of dermatitis was strikingly inhibited, as assessed by SCORAD index and serological parameters including LDH5 activity and a number of peripheral eosinophils. A sharp reduction in eosinophils and neutrophils was observed prior to improvement in the skin inflammation. In addition, PGE2 production by peripheral blood mononuclear cells was reduced by this treatment. In contrast, serum IgE levels did not change during the same period. Although this study is an open-trial one, it suggests that this treatment may be useful for the treatment of adult patients with severe atopic dermatitis. |
nfcorpus-qrel-MED-2442 | Generate text that best answers this question: caloric restriction | Double-blind, controlled, crossover study of cyclosporin in adults with severe refractory atopic dermatitis.
A few patients remain severely affected by atopic dermatitis into adult life despite treatment with systemic steroids, azathioprine, and photochemotherapy. 33 patients took part in a double-blind, placebo-controlled, crossover study to assess the efficacy and safety of cyclosporin (5 mg/kg per day) in adults with severe refractory atopic dermatitis. Treatments were given for eight weeks each with one group (n = 16) receiving placebo followed by cyclosporin and another (n = 17) receiving cyclosporin and then placebo. Disease activity, extent of disease, sleep and itch, topical steroid use, and adverse events were assessed every two weeks. Both extent and activity of dermatitis were significantly improved (p less than 0.001) as were subjective measures of disease. 20 patients receiving cyclosporin reported adverse events compared with 8 taking placebo, although no patient required withdrawal from the study. Cyclosporin therapy led to an increase in the mean serum urea, creatinine, and bilirubin concentrations, although only the rise in bilirubin was significant (p = 0.001). Our results confirm that cyclosporin is a safe and effective short-term treatment for severe, refractory atopic dermatitis. |
nfcorpus-qrel-MED-2472 | Generate text that best answers this question: caloric restriction | Vegan regimen with reduced medication in the treatment of bronchial asthma.
Thirty-five patients who had suffered from bronchial asthma for an average of 12 yr, all receiving long-term medication, 20 including cortisone, were subject to therapy with vegan food for 1 yr. In almost all cases, medication was withdrawn or drastically reduced. There was a significant decrease in asthma symptoms. Twenty-four patients (69%) fulfilled the treatment. Of these, 71% reported improvement at 4 months and 92% at 1 yr. There was a significant improvement in a number of clinical variables; for example, vital capacity, forced expiratory volume at one sec and physical working capacity, as well as a significant change in various biochemical indices as haptoglobin, IgM, IgE, cholesterol, and triglycerides in blood. Selected patients, with a fear of side-effects of medication, who are interested in alternative health care, might get well and replace conventional medication with this regimen. |
nfcorpus-qrel-MED-2444 | Generate text that best answers this question: caloric restriction | Side-effect profile of cyclosporin A in patients treated for psoriasis.
This is a review of the side-effects of cyclosporin A (CyA) in patients with severe psoriasis; renal dysfunction and hypertension are discussed elsewhere. In particular, paraesthesia, hypertrichosis, gingival hyperplasia and gastrointestinal disorders may occur, but are generally transient, mild-to-moderate in severity and only rarely require discontinuation of CyA. Infections are not a problem. As expected with an immunosuppressive drug, there is the possible risk of tumour development, particularly squamous cell carcinomas. However, these skin malignancies developed almost exclusively in patients previously treated with PUVA and/or methotrexate. The few lymphoproliferative disorders regressed spontaneously on discontinuation of the drug. Whether the isolated cases of solid tumours were CyA-related is not known. Apart from a raised serum creatinine, an important indicator of renal dysfunction, the laboratory abnormalities included hypomagnesaemia, hyperkalaemia, increased uric acid, changes in liver function tests, and fluctuations in the serum cholesterol and triglyceride levels. Although most of these changes were not clinically relevant, laboratory monitoring of patients with psoriasis treated with CyA is essential. |
nfcorpus-qrel-MED-2501 | Generate text that best answers this question: caloric restriction | Amino acid sensing and regulation of mTORC1.
Amino acids play fundamental roles in the cell both as the building blocks of new proteins and as metabolic precursors. To adapt to their limitation during periods of protein starvation, multiple adaptive mechanisms have evolved, including a rapid cessation of new protein synthesis, an increase in amino acid biosynthesis and transport, and autophagy. Here, we discuss what we currently know about how amino acid limitation is sensed, and how this sensing might be transmitted to mTORC1 to regulate protein synthesis and autophagy. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-2506 | Generate text that best answers this question: caloric restriction | Caloric restriction, the traditional Okinawan diet, and healthy aging: the diet of the world's longest-lived people and its potential impact on mor...
Long-term caloric restriction (CR) is a robust means of reducing age-related diseases and extending life span in multiple species, but the effects in humans are unknown. The low caloric intake, long life expectancy, and the high prevalence of centenarians in Okinawa have been used as an argument to support the CR hypothesis in humans. However, no long-term, epidemiologic analysis has been conducted on traditional dietary patterns, energy balance, and potential CR phenotypes for the specific cohort of Okinawans who are purported to have had a calorically restricted diet. Nor has this cohort's subsequent mortality experience been rigorously studied. Therefore, we investigated six decades of archived population data on the elderly cohort of Okinawans (aged 65-plus) for evidence of CR. Analyses included traditional diet composition, energy intake, energy expenditure, anthropometry, plasma DHEA, mortality from age-related diseases, and current survival patterns. Findings include low caloric intake and negative energy balance at younger ages, little weight gain with age, life-long low BMI, relatively high plasma DHEA levels at older ages, low risk for mortality from age-related diseases, and survival patterns consistent with extended mean and maximum life span. This study lends epidemiologic support for phenotypic benefits of CR in humans and is consistent with the well-known literature on animals with regard to CR phenotypes and healthy aging. |
nfcorpus-qrel-MED-2512 | Generate text that best answers this question: caloric restriction | Extending healthy ageing: nutrient sensitive pathway and centenarian population
Ageing is a challenge for any living organism and human longevity is a complex phenotype. With increasing life expectancy, maintaining long-term health, functionality and well-being during ageing has become an essential goal. To increase our understanding of how ageing works, it may be advantageous to analyze the phenotype of centenarians, perhaps one of the best examples of successful ageing. Healthy ageing involves the interaction between genes, the environment, and lifestyle factors, particularly diet. Besides evaluating specific gene-environment interactions in relation to exceptional longevity, it is important to focus attention on modifiable lifestyle factors such as diet and nutrition to achieve extension of health span. Furthermore, a better understanding of human longevity may assist in the design of strategies to extend the duration of optimal human health. In this article we briefly discuss relevant topics on ageing and longevity with particular focus on dietary patterns of centenarians and nutrient-sensing pathways that have a pivotal role in the regulation of life span. Finally, we also discuss the potential role of Nrf2 system in the pro-ageing signaling emphasizing its phytohormetic activation. |
nfcorpus-qrel-MED-2514 | Generate text that best answers this question: caloric restriction | Why human lifespan is rapidly increasing: solving "longevity riddle" with "revealed-slow-aging" hypothesis
Healthy life span is rapidly increasing and human aging seems to be postponed. As recently exclaimed in Nature, these findings are so perplexing that they can be dubbed the 'longevity riddle'. To explain current increase in longevity, I discuss that certain genetic variants such as hyper-active mTOR (mTarget of Rapamycin) may increase survival early in life at the expense of accelerated aging. In other words, robustness and fast aging may be associated and slow-aging individuals died prematurely in the past. Therefore, until recently, mostly fast-aging individuals managed to survive into old age. The progress of civilization (especially 60 years ago) allowed slow-aging individuals to survive until old age, emerging as healthy centenarians now. I discuss why slow aging is manifested as postponed (healthy) aging, why the rate of deterioration is independent from aging and also entertain hypothetical use of rapamycin in different eras as well as the future of human longevity. |
nfcorpus-qrel-MED-2943 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3051 | Generate text that best answers this question: caloric restriction | Functional MRI of human hypothalamic responses following glucose ingestion.
The hypothalamus is intimately involved in the regulation of food intake, integrating multiple neural and hormonal signals. Several hypothalamic nuclei contain glucose-sensitive neurons, which play a crucial role in energy homeostasis. Although a few functional magnetic resonance imaging (fMRI) studies have indicated that glucose consumption has some effect on the neuronal activity levels in the hypothalamus, this matter has not been investigated extensively yet. For instance, dose-dependency of the hypothalamic responses to glucose ingestion has not been addressed. We measured the effects of two different glucose loads on neuronal activity levels in the human hypothalamus using fMRI. After an overnight fast, the hypothalamus of 15 normal weight men was scanned continuously for 37 min. After 7 min, subjects ingested either water or a glucose solution containing 25 or 75 g of glucose. We observed a prolonged decrease of the fMRI signal in the hypothalamus, which started shortly after subjects began drinking the glucose solution and lasted for at least 30 min. Moreover, the observed response was dose-dependent: a larger glucose load resulted in a larger signal decrease. This effect was most pronounced in the upper anterior hypothalamus. In the upper posterior hypothalamus, the signal decrease was similar for both glucose loads. No effect was found in the lower hypothalamus. We suggest a possible relation between the observed hypothalamic response and changes in the blood insulin concentration. |
nfcorpus-qrel-MED-3055 | Generate text that best answers this question: caloric restriction | Food and drug reward: overlapping circuits in human obesity and addiction.
Both drug addiction and obesity can be defined as disorders in which the saliency value of one type of reward (drugs and food, respectively) becomes abnormally enhanced relative to, and at the expense of others. This model is consistent with the fact that both drugs and food have powerful reinforcing effects-partly mediated by dopamine increases in the limbic system-that, under certain circumstances or in vulnerable individuals, could overwhelm the brain's homeostatic control mechanisms. Such parallels have generated significant interest in understanding the shared vulnerabilities and trajectories between addiction and obesity. Now, brain imaging discoveries have started to uncover common features between these two conditions and to delineate some of the overlapping brain circuits whose dysfunctions may explain stereotypic and related behavioral deficits in human subjects. These results suggest that both obese and drug-addicted individuals suffer from impairments in dopaminergic pathways that regulate neuronal systems associated not only with reward sensitivity and incentive motivation, but also with conditioning (memory/learning), impulse control (behavioural inhibition), stress reactivity, and interoceptive awareness. Here, we integrate findings predominantly derived from positron emission tomography that shed light on the role of dopamine in drug addiction and in obesity, and propose an updated working model to help identify treatment strategies that may benefit both of these conditions. |
nfcorpus-qrel-MED-3056 | Generate text that best answers this question: caloric restriction | The opioid system and food intake: homeostatic and hedonic mechanisms.
Opioids are important in reward processes leading to addictive behavior such as self-administration of opioids and other drugs of abuse including nicotine and alcohol. Opioids are also involved in a broadly distributed neural network that regulates eating behavior, affecting both homeostatic and hedonic mechanisms. In this sense, opioids are particularly implicated in the modulation of highly palatable foods, and opioid antagonists attenuate both addictive drug taking and appetite for palatable food. Thus, craving for palatable food could be considered as a form of opioid-related addiction. There are three main families of opioid receptors (µ, ĸ, and δ) of which µ-receptors are most strongly implicated in reward. Administration of selective µ-agonists into the NAcc of rodents induces feeding even in satiated animals, while administration of µ-antagonists reduces food intake. Pharmacological studies also suggest a role for ĸ- and δ-opioid receptors. Preliminary data from transgenic knockout models suggest that mice lacking some of these receptors are resistant to high-fat diet-induced obesity. Copyright © 2012 S. Karger GmbH, Freiburg. |
nfcorpus-qrel-MED-3057 | Generate text that best answers this question: caloric restriction | Brain PET imaging in obesity and food addiction: current evidence and hypothesis.
The ongoing epidemics of obesity is one main health concern of the present time. Overeating in some obese individuals shares similarities with the loss of control and compulsive behavior observed in drug-addicted subjects, suggesting that obesity may involve food addiction. Here, we review the contributions provided by the use of positron emission tomography to the current understanding of the cerebral control of obesity and food intake in humans. The available studies have shown that multiple areas in the brain are involved with the reward properties of food, such as prefrontal, orbitofrontal, somatosensory cortices, insula, thalamus, hypothalamus, amygdala, and others. This review summarizes the current evidence, supporting the concepts that i) regions involved in the somatosensory response to food sight, taste, and smell are activated by palatable foods and may be hyperresponsive in obese individuals, ii) areas controlling executive drive seem to overreact to the anticipation of pleasure during cue exposure, and iii) those involved in cognitive control and inhibitory behavior may be resistant to the perception of reward after food exposure in obese subjects. All of these features may stimulate, for different reasons, ingestion of highly palatable and energy-rich foods. Though these same regions are similarly involved in drug abusers and game-addicted individuals, any direct resemblance may be an oversimplification, especially as the heterogeneities between studies and the prevalent exclusion of sensitive groups still limit a coherent interpretation of the findings. Further work is required to comprehensively tackle the multifaceted phenotype of obesity and identify the role of food dependency in its pathophysiology. Copyright © 2012 S. Karger GmbH, Freiburg. |
nfcorpus-qrel-MED-3270 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3271 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3272 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3274 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3275 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3277 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3278 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3279 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3280 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3281 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-3282 | Generate text that best answers this question: caloric restriction | 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-qrel-MED-4120 | Generate text that best answers this question: caloric restriction | Sucrose activates human taste pathways differently from artificial sweetener.
Animal models suggest that sucrose activates taste afferents differently than non-caloric sweeteners. Little information exists how artificial sweeteners engage central taste pathways in the human brain. We assessed sucrose and sucralose taste pleasantness across a concentration gradient in 12 healthy control women and applied 10% sucrose and matched sucralose during functional magnet resonance imaging. The results indicate that (1) both sucrose and sucralose activate functionally connected primary taste pathways; (2) taste pleasantness predicts left insula response; (3) sucrose elicits a stronger brain response in the anterior insula, frontal operculum, striatum and anterior cingulate, compared to sucralose; (4) only sucrose, but not sucralose, stimulation engages dopaminergic midbrain areas in relation to the behavioral pleasantness response. Thus, brain response distinguishes the caloric from the non-caloric sweetener, although the conscious mind could not. This could have important implications on how effective artificial sweeteners are in their ability to substitute sugar intake. |
nfcorpus-qrel-MED-4121 | Generate text that best answers this question: caloric restriction | Effect of covert nutritive dilution on the spontaneous food intake of obese individuals: a pilot study.
The present study investigated the feasibility of a new experimental approach for studying the effect of covert nutritive dilution on the spontaneous food intake of obese individuals. Eight obese subjects were studied as inpatients on a metabolic unit for 15 days during which time they were unaware that their food intake was being monitored. A platter method of food presentation encouraged ad libitum ingestion. Caloric dilution was achieved by replacing sucrose-containing products with aspartame-sweetened analogues in an otherwise normal diet. During the base-line period the subjects spontaneously ate sufficient conventional food to maintain or even slightly increase body weight. Covert substitution of aspartame-sweetened products for their sucrose counterparts resulted in an immediate reduction in spontaneous energy intake of approximately 25%. The aspartame analogues were as well accepted as their conventional counterparts, as indicated by the equal quantity of each consumed. These preliminary results demonstrate that, in a metabolic ward setting, it is possible to maintain the spontaneous food intake of obese individuals at levels sufficient to preserve body weight and arbitrarily to decrease those levels of intake by 25% or more through covert changes in the caloric density of the diet. |
nfcorpus-qrel-MED-4124 | Generate text that best answers this question: caloric restriction | Erythritol is a sweet antioxidant.
OBJECTIVE: Hyperglycemia, oxidative stress, and the onset and progression of diabetic complications are strongly linked. Reduction of oxidative stress could be of utmost importance in the long-term treatment of diabetic patients. The chronic nature of the disease calls for a mode of antioxidant intake that can be sustained easily, e.g., by the diet. Erythritol, a simple polyol, could be such a compound. It is orally available, well tolerated, and its chemical structure resembles that of mannitol, a well-known hydroxyl radical (HO*) scavenger. METHODS: We studied the antioxidant properties of erythritol in vitro and subsequently determined its antioxidant activity and its vasoprotective effect in the streptozotocin diabetic rat. RESULTS: Erythritol was shown to be an excellent HO* radical scavenger and an inhibitor of 2,2'-azobis-2-amidinopropane dihydrochloride-induced hemolysis but inert toward superoxide radicals. High-performance liquid chromatographic and electron spin resonance spectroscopy studies showed that the reaction of erythritol with hydroxyl radicals resulted in the formation of erythrose and erythrulose by abstraction of a carbon-bound hydrogen atom. In the streptozotocin diabetic rat, erythritol displayed an endothelium-protective effect and, in accordance with the in vitro experiments, erythrose was found in the urine of erythritol-consuming rats. CONCLUSION: Erythritol acts as an antioxidant in vivo and may help protect against hyperglycemia-induced vascular damage. Copyright 2010 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-4321 | Generate text that best answers this question: caloric restriction | Dehydroepiandrosterone sulfate and postmenopausal women.
PURPOSE OF REVIEW: Levels of dehydroepiandrosterone (DHEA) are known to decline with age. In an era of increasing use of supplements to better life, the benefits of DHEA in the aging female population are controversial. The goal of this article is to critically review published studies to determine if there is a role for DHEA supplementation in postmenopausal women. RECENT FINDINGS: Daily administration of oral DHEA achieves serum concentrations similar to those of women in their 20s. Several observational studies have shown that lower DHEA levels are associated with increased cardiovascular risk in women; however, interventional trials show no improvement in atherosclerosis or cardiovascular risk factors, and a lowering of HDL cholesterol levels. DHEA supplementation modestly increases bone mineral density in conjunction with adjuvant therapies and improves cognition in those with mild-to-moderate cognitive impairment, but does not affect cognition in unimpaired women. Use of intravaginal DHEA, but not oral DHEA, alleviates vaginal atrophy and improves sexual function in postmenopausal women. SUMMARY: On the basis of current evidence, there is no role for oral DHEA supplementation in healthy, postmenopausal women. Where benefits have been shown, long-term studies are needed to confirm these benefits and verify the safety profile of DHEA. |
nfcorpus-qrel-MED-4322 | Generate text that best answers this question: caloric restriction | DHEA therapy in postmenopausal women: the need to move forward beyond the lack of evidence.
The marked age-related decline in serum dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) has suggested that a deficiency of these steroids may be causally related to the development of a series of diseases that are generally associated with aging. Postulated consequences of low DHEA levels include insulin resistance, obesity, cardiovascular disease, cancer, reduction of the immune defence system as well as psychosocial problems such as depression and a general deterioration in the sensation of well-being and cognitive function. Clinically, the spectrum of women that would benefit from DHEA therapy is not clearly defined and nor is the dosage of hormone treatment. Whether DHEA therapy could be prescribed as a general anti-aging therapy or could be an alternative treatment for women suffering from androgen deficiency syndrome remains uncertain across studies. The lack of definitive evidence for biological mechanisms and the presence of only a few studies that address these emerging issues of DHEA therapy in postmenopausal women might encourage a new critical analysis of the available literature, evidencing current limits and incongruities. |
nfcorpus-qrel-MED-4323 | Generate text that best answers this question: caloric restriction | Dehydroepiandrosterone and ageing.
Dehydroepiandrosterone (DHEA) is the major steroid produced by the adrenal zona reticularis and, in contrast to cortisol and aldosterone, its secretion declines with ageing. This has generated major interest in its putative role as an 'anti-ageing' hormone. However, it is not clear that the age-associated, physiological decline in DHEA secretion represents a harmful deficiency. DHEA exhibits its action mainly by conversion to sex steroids. In addition, DHEA has neurosteroidal properties and may exhibit direct action via specific binding sites on endothelial cells. There is convincing evidence for beneficial effects of DHEA in patients with adrenal insufficiency and future research will hopefully elucidate its role in patients receiving pharmacological glucocorticoid treatment. However, in healthy elderly subjects, current evidence from randomised, controlled trials does not justify the use of DHEA, with no major beneficial effects reported and, in addition, potentially adverse effects on sex steroid-dependent tumour growth need to be considered. Copyright 2004 Elsevier Ltd. |
nfcorpus-qrel-MED-4996 | Generate text that best answers this question: caloric restriction | From the Cover: Caloric restriction improves memory in elderly humans
Animal studies suggest that diets low in calories and rich in unsaturated fatty acids (UFA) are beneficial for cognitive function in age. Here, we tested in a prospective interventional design whether the same effects can be induced in humans. Fifty healthy, normal- to overweight elderly subjects (29 females, mean age 60.5 years, mean body mass index 28 kg/m2) were stratified into 3 groups: (i) caloric restriction (30% reduction), (ii) relative increased intake of UFAs (20% increase, unchanged total fat), and (iii) control. Before and after 3 months of intervention, memory performance was assessed under standardized conditions. We found a significant increase in verbal memory scores after caloric restriction (mean increase 20%; P < 0.001), which was correlated with decreases in fasting plasma levels of insulin and high sensitive C-reactive protein, most pronounced in subjects with best adherence to the diet (all r values < −0.8; all P values <0.05). Levels of brain-derived neurotrophic factor remained unchanged. No significant memory changes were observed in the other 2 groups. This interventional trial demonstrates beneficial effects of caloric restriction on memory performance in healthy elderly subjects. Mechanisms underlying this improvement might include higher synaptic plasticity and stimulation of neurofacilitatory pathways in the brain because of improved insulin sensitivity and reduced inflammatory activity. Our study may help to generate novel prevention strategies to maintain cognitive functions into old age. |
nfcorpus-qrel-MED-4841 | Generate text that best answers this question: canker sores | Humoral immunity to cow's milk proteins and gliadin within the etiology of recurrent aphthous ulcers?
OBJECTIVES: The goal of this study was to determine the incidence of serum antibodies to gliadin and to cow's milk proteins (CMP) using ELISA test, within patients who have recurrent aphthous ulcers (RAU). SUBJECTS AND METHODS: Fifty patients with recurrent aphthous ulcers and fifty healthy people were included in this research. Levels of serum IgA and IgG antibodies to gliadin and IgA, IgG and IgE to CMP were determined using ELISA. RESULTS: The levels of serum antigliadin IgA and IgG antibodies were not significantly higher in patients with RAU in comparison with the controls (P = 0.937 and P = 0.1854 respectively). The levels of serum anti-CMP IgA, IgG and IgE antibodies were significantly higher in patients with RAU in comparison with the controls (P < 0.005, P < 0.002 and P < 0.001 respectively). In general, the increased humoral (IgA or IgG) immunoreactivity to CMP was found in 32 of 50 patients, while 17 of them showed the increased levels of both IgA and IgG immunoreactivity to CMP. At the same time, 16 out of 50 patients had IgA, IgG and IgE immunoreactivity to CMP. CONCLUSION: These results indicate the strong association between high levels of serum anti-CMP IgA, IgG and IgE antibodies and clinical manifestations of recurrent aphthous ulcers. |
nfcorpus-qrel-MED-2568 | Generate text that best answers this question: carcinogens | IP6: a novel anti-cancer agent.
Inositol hexaphosphate (InsP6 or IP6) is ubiquitous. At 10 microM to 1 mM concentrations, IP6 and its lower phosphorylated forms (IP(1-5)) as well as inositol (Ins) are contained in most mammalian cells, wherein they are important in regulating vital cellular functions such as signal transduction, cell proliferation and differentiation. A striking anti-cancer action of IP6 has been demonstrated both in vivo and in vitro, which is based on the hypotheses that exogenously administered IP6 may be internalized, dephosphorylated to IP(1-5), and inhibit cell growth. There is additional evidence that Ins alone may further enhance the anti-cancer effect of IP6. Besides decreasing cellular proliferation, IP6 also causes differentiation of malignant cells often resulting in a reversion to normal phenotype. These data strongly point towards the involvement of signal transduction pathways, cell cycle regulatory genes, differentiation genes, oncogenes and perhaps, tumor suppressor genes in bringing about the observed anti-neoplastic action of IP6. |
nfcorpus-qrel-MED-2988 | Generate text that best answers this question: carcinogens | The role of phytic acid in legumes: antinutrient or beneficial function?
This review describes the present state of knowledge about phytic acid (phytate), which is often present in legume seeds. The antinutritional effects of phytic acid primarily relate to the strong chelating associated with its six reactive phosphate groups. Its ability to complex with proteins and particularly with minerals has been a subject of investigation from chemical and nutritional viewpoints. The hydrolysis of phytate into inositol and phosphates or phosphoric acid occurs as a result of phytase or nonenzymatic cleavage. Enzymes capable of hydrolysing phytates are widely distributed in micro-organisms, plants and animals. Phytases act in a stepwise manner to catalyse the hydrolysis of phytic acid. To reduce or eliminate the chelating ability of phytate, dephosphorylation of hexa- and penta-phosphate forms is essential since a high degree of phosphorylation is necessary to bind minerals. There are several methods of decreasing the inhibitory effect of phytic acid on mineral absorption (cooking, germination, fermentation, soaking, autolysis). Nevertheless, inositol hexaphosphate is receiving increased attention owing to its role in cancer prevention and/or therapy and its hypocholesterolaemic effect. |
nfcorpus-qrel-MED-2559 | Generate text that best answers this question: carcinogens | Effect of IP6 on human neutrophil cytokine production and cell morphology.
Inositol hexaphosphate (IP6) has anti-cancer properties, but recently other extracellular functions have been observed for IP6, including enhancing superoxide production and phagocytosis by neutrophils in the presence of microbial stimuli. This study investigated other inflammatory functions of IP6 on adherent neutrophils. The effect of IP6 on the release of IL-8, tumour necrosis factor (TNF-alpha) and IL-6 by neutrophils attached to either plastic or laminin for up to 6 hours in response to stimulation with lipopolysaccharide or N-formyl-Met-Leu-Phe (fMLP) was investigated. An increase in IL-8 secretion by stimulated cells occurred in the presence of IP6. The incubation of cells attached to laminin with IP6 alone (100-250 BM) did not effect cell morphology, but in the presence of 10(-7) M fMLP altered cell shape. A direct effect of IP6 on cell function was to trigger a sustained assembly of F-actin. Thus, exposure of neutrophils to low levels of IP6 appears to modulate selective neutrophil functions. |
nfcorpus-qrel-MED-4319 | Generate text that best answers this question: carcinogens | Phytate in foods and significance for humans: food sources, intake, processing, bioavailability, protective role and analysis.
The article gives an overview of phytic acid in food and of its significance for human nutrition. It summarises phytate sources in foods and discusses problems of phytic acid/phytate contents of food tables. Data on phytic acid intake are evaluated and daily phytic acid intake depending on food habits is assessed. Degradation of phytate during gastro-intestinal passage is summarised, the mechanism of phytate interacting with minerals and trace elements in the gastro-intestinal chyme described and the pathway of inositol phosphate hydrolysis in the gut presented. The present knowledge of phytate absorption is summarised and discussed. Effects of phytate on mineral and trace element bioavailability are reported and phytate degradation during processing and storage is described. Beneficial activities of dietary phytate such as its effects on calcification and kidney stone formation and on lowering blood glucose and lipids are reported. The antioxidative property of phytic acid and its potentional anticancerogenic activities are briefly surveyed. Development of the analysis of phytic acid and other inositol phosphates is described, problems of inositol phosphate determination and detection discussed and the need for standardisation of phytic acid analysis in foods argued. |
nfcorpus-qrel-MED-2570 | Generate text that best answers this question: carcinogens | In vitro investigations of the potential health benefits of Australian-grown faba beans (Vicia faba L.): chemopreventative capacity and inhibitory ...
The functional properties, including antioxidant and chemopreventative capacities as well as the inhibitory effects on angiotensin-converting enzyme (ACE), α-glucosidase and pancreatic lipase, of three Australian-grown faba bean genotypes (Nura, Rossa and TF(Ic*As)*483/13) were investigated using an array of in vitro assays. Chromatograms of on-line post column derivatisation assay coupled with HPLC revealed the existence of active phenolics (hump) in the coloured genotypes, which was lacking in the white-coloured breeding line, TF(Ic*As)*483/13. Roasting reduced the phenolic content, and diminished antioxidant activity by 10-40 % as measured by the reagent-based assays (diphenylpicrylhydrazyl, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and oxygen radical absorbance capacity) in all genotypes. Cell culture-based antioxidant activity assay (cellular antioxidant activity) showed an increase of activity in the coloured genotypes after roasting. Faba bean extracts demonstrated cellular protection ability against H₂O₂-induced DNA damage (assessed using RAW264.7 cells), and inhibited the proliferation of all human cancer cell lines (BL13, AGS, Hep G2 and HT-29) evaluated. However, the effect of faba bean extracts on the non-transformed human cells (CCD-18Co) was negligible. Flow cytometric analyses showed that faba bean extracts successfully induced apoptosis of HL-60 (acute promyelocytic leukaemia) cells. The faba bean extracts also exhibited ACE, α-glucosidase and pancreatic lipase inhibitory activities. Overall, extracts from Nura (buff-coloured) and Rossa (red-coloured) were comparable, while TF(Ic*As)*483/13 (white-coloured) contained the lowest phenolic content and exhibited the least antioxidant and enzyme inhibition activities. These results are important to promote the utilisation of faba beans in human diets for various health benefits. |
nfcorpus-qrel-MED-2573 | Generate text that best answers this question: carcinogens | Anti-angiogenic activity of inositol hexaphosphate (IP6).
A significant anticancer activity of the naturally occurring carbohydrate inositol hexaphosphate (IP(6)) has been reported against numerous cancer models. Since tumors require angiogenesis for growth and metastasis, we hypothesize that IP(6) reduces tumor growth by inhibiting angiogenesis. Because angiogenesis depends on the interaction between endothelial and tumor cells, we investigated the effect of IP(6) on both. IP(6) inhibited the proliferation and induced the differentiation of endothelial cells in vitro; the growth of bovine aortic endothelial cells (BAECs) evaluated by MTT proliferation assay was inhibited in a dose-dependent manner (IC(50) = 0.74 mM). The combination of IP(6) and vasostatin, a calreticulin fragment with anti-angiogenic activity, was synergistically superior in growth inhibition than either compound. IP(6) inhibited human umbilical vein endothelial cell (HUVEC) tube formation (in vitro capillary differentiation) on a reconstituted extracellular matrix, Matrigel, and disrupted pre-formed tubes. IP(6) significantly reduced basic fibroblast growth factor (bFGF)-induced vessel formation (P < 0.01) in vivo in Matrigel plug assay. Exposure of HepG2, a human hepatoma cell line, to IP(6) for 8 h, resulted in a dose-dependent decrease in the mRNA levels of vascular endothelial growth factor (VEGF), as assessed by RT-PCR. IP(6) treatment of HepG2 cells for 24 h also significantly reduced the VEGF protein levels in conditioned medium, in a concentration-dependent manner (P = 0.012). Thus, IP(6) has an inhibitory effect on induced angiogenesis. |
nfcorpus-qrel-MED-2574 | Generate text that best answers this question: carcinogens | Protection against cancer by dietary IP6 and inositol.
Inositol hexaphosphate (IP(6)) is a naturally occurring polyphosphorylated carbohydrate, abundantly present in many plant sources and in certain high-fiber diets, such as cereals and legumes. In addition to being found in plants, IP(6) is contained in almost all mammalian cells, although in much smaller amounts, where it is important in regulating vital cellular functions such as signal transduction, cell proliferation, and differentiation. For a long time IP(6) has been recognized as a natural antioxidant. Recently IP(6) has received much attention for its role in cancer prevention and control of experimental tumor growth, progression, and metastasis. In addition, IP(6) possesses other significant benefits for human health, such as the ability to enhance immune system, prevent pathological calcification and kidney stone formation, lower elevated serum cholesterol, and reduce pathological platelet activity. In this review we show the efficacy and discuss some of the molecular mechanisms that govern the action of this dietary agent. Exogenously administered IP(6) is rapidly taken up into cells and dephosphorylated to lower inositol phosphates, which further affect signal transduction pathways resulting in cell cycle arrest. A striking anticancer action of IP(6) was demonstrated in different experimental models. In addition to reducing cell proliferation, IP(6) also induces differentiation of malignant cells. Enhanced immunity and antioxidant properties also contribute to tumor cell destruction. Preliminary studies in humans show that IP(6) and inositol, the precursor molecule of IP(6), appear to enhance the anticancer effect of conventional chemotherapy, control cancer metastases, and improve quality of life. Because it is abundantly present in regular diet, efficiently absorbed from the gastrointestinal tract, and safe, IP(6) + inositol holds great promise in our strategies for cancer prevention and therapy. There is clearly enough evidence to justify the initiation of full-scale clinical trials in humans. |
nfcorpus-qrel-MED-2585 | Generate text that best answers this question: carcinogens | Cancer inhibition by inositol hexaphosphate (IP6) and inositol: from laboratory to clinic.
Inositol hexaphosphate (IP6) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plant and mammalian cells. It was recently recognized to possess multiple biological functions. A striking anticancer effect of IP6 was demonstrated in different experimental models. Inositol is also a natural constituent possessing moderate anticancer activity. The most consistent and best anticancer results were obtained from the combination of IP6 plus inositol. In addition to reducing cell proliferation, IP6 increases differentiation of malignant cells, often resulting in a reversion to normal phenotype. Exogenously administered IP6 is rapidly taken into the cells and dephosphorylated to lower-phosphate inositol phosphates, which further interfere with signal transduction pathways and cell cycle arrest. Enhanced immunity and antioxidant properties can also contribute to tumor cell destruction. However, the molecular mechanisms underlying this anticancer action are not fully understood. Because it is abundantly present in regular diet, efficiently absorbed from the gastrointestinal tract, and safe, IP6 holds great promise in our strategies for the prevention and treatment of cancer. IP6 plus inositol enhances the anticancer effect of conventional chemotherapy, controls cancer metastases, and improves the quality of life, as shown in a pilot clinical trial. The data strongly argue for the use of IP6 plus inositol in our strategies for cancer prevention and treatment. However, the effectiveness and safety of IP6 plus inositol at therapeutic doses needs to be determined in phase I and phase II clinical trials in humans. |
nfcorpus-qrel-MED-2599 | Generate text that best answers this question: carcinogens | Curcumin sensitizes tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis through reactive oxygen species-mediated upre...
Curcumin exhibits anti-inflammatory and antitumor activities. Although its functional mechanism has not been elucidated so far, numerous studies have shown that curcumin induces apoptosis in cancer cells. In the present study, we show that subtoxic concentrations of curcumin sensitize human renal cancer cells to the tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis. This apoptosis induced by the combination of curcumin and TRAIL is not interrupted by Bcl-2 overexpression. We found that treatment with curcumin significantly induces death receptor 5 (DR5) expression both at its mRNA and protein levels, accompanying the generation of the reactive oxygen species (ROS). Not only the pretreatment with N-acetylcystine but also the ectopic expression of peroxiredoxin II, an antioxidative protein, dramatically inhibited the apoptosis induced by curcumin and TRAIL in combination, blocking the curcumin-mediated DR5 upregulation. Taken together, the present study demonstrates that curcumin enhances TRAIL-induced apoptosis by ROS-mediated DR5 upregulation. |
nfcorpus-qrel-MED-2607 | Generate text that best answers this question: carcinogens | New perspectives of curcumin in cancer prevention
Numerous natural compounds have been extensively investigated for their potential for cancer prevention over decades. Curcumin, from Curcuma longa, is a highly promising natural compound that can be potentially used for chemoprevention of multiple cancers. Curcumin modulates multiple molecular pathways involved in the lengthy carcinogenesis process to exert its chemopreventive effects through several mechanisms: promoting apoptosis, inhibiting survival signals, scavenging reactive oxidative species (ROS), and reducing the inflammatory cancer microenvironment. Curcumin fulfills the characteristics for an ideal chemopreventive agent with its low toxicity, affordability, and easy accessibility. Nevertheless, the clinical application of curcumin is currently compromised by its poor bioavailability. Here we review the potential of curcumin in cancer prevention, its molecular targets, and action mechanisms. Finally, we suggest specific recommendations to improve its efficacy and bioavailability for clinical applications. |
nfcorpus-qrel-MED-2602 | Generate text that best answers this question: carcinogens | Curcumin induces apoptosis in human melanoma cells through a Fas receptor/caspase-8 pathway independent of p53.
In this study, we investigated the molecular pathways targeted by curcumin during apoptosis of human melanoma cell lines. We found that curcumin caused cell death in eight melanoma cell lines, four with wild-type and four with mutant p53. We demonstrate that curcumin-induced apoptosis is both dose- and time-dependent. We found that curcumin did not induce p53, suggesting that curcumin activates other apoptosis pathways. Our data show that curcumin activates caspases-3 and -8 but not caspase-9, supporting the rationale that apoptosis occurs via a membrane-mediated mechanism. Both a caspase-8 and broad-based caspase inhibitor, but not a caspase-9 specific inhibitor, suppressed curcumin-induced cell death. To further support our hypothesis that curcumin induces activation of a death receptor pathway, we show that curcumin induces Fas receptor aggregation in a FasL-independent manner and that low-temperature incubation, previously shown to inhibit receptor aggregation, prevented curcumin-induced cell death. Moreover, we demonstrate that expression of dominant negative FADD significantly inhibited curcumin-induced cell death. In addition, our results indicate that curcumin also blocks the NF-kappaB cell survival pathway and suppresses the apoptotic inhibitor, XIAP. Since melanoma cells with mutant p53 are strongly resistant to conventional chemotherapy, curcumin may overcome the chemoresistance of these cells and provide potential new avenues for treatment. |
nfcorpus-qrel-MED-2603 | Generate text that best answers this question: carcinogens | FADD: a regulator of life and death.
FAS-associated protein with death domain (FADD) is the key adaptor protein transmitting apoptotic signals mediated by the main death receptors (DRs). Besides being an essential instrument in cell death, FADD is also implicated in proliferation, cell cycle progression, tumor development, inflammation, innate immunity, and autophagy. Recently, many of these new functions of FADD were shown to be independent of DRs. Moreover, FADD function is dictated by protein localization and phosphorylation state. Thus, FADD is a crucial and unique controller of many essential cellular processes. The full understanding of the networks dictating the ultimate function of FADD may provide a new paradigm for other multifaceted proteins. Copyright 2010 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-2605 | Generate text that best answers this question: carcinogens | Curcumin-induced apoptosis of human colon cancer colo 205 cells through the production of ROS, Ca2+ and the activation of caspase-3.
Curcumin (diferuloylmethane), the yellow pigment in turmeric (Curcuma longa), is known to inhibit proliferation of cancer cells by arresting them at various phases of the cell cycle and to induce apoptosis in tumor cells. Curcumin-induced apoptosis mainly involves the activation of caspase-3 and mitochondria-mediated pathway in various cancer cells of different tissue origin. In the present study, the induction of apoptosis and cytotoxicity by curcumin in colon cancer colo 205 cells was investigated by using flow cytometry. The results demonstrated that curcumin induced cytotoxicity and apoptosis dose- and time-depedently. Curcumin induced the production of reactive oxygen species (ROS) and Ca+2, decreased the levels of mitochondria membrane potential and induced caspase-3 activity. Curcumin also promoted the expression of Bax, cytochrome C, p53 and p21 but inhibited the expression of Bcl-2. These observations suggest that curcumin may have a possible therapeutic potential in colon cancer patients. |
nfcorpus-qrel-MED-2604 | Generate text that best answers this question: carcinogens | Curcumin and Cancer Cells: How Many Ways Can Curry Kill Tumor Cells Selectively?
Cancer is a hyperproliferative disorder that is usually treated by chemotherapeutic agents that are toxic not only to tumor cells but also to normal cells, so these agents produce major side effects. In addition, these agents are highly expensive and thus not affordable for most. Moreover, such agents cannot be used for cancer prevention. Traditional medicines are generally free of the deleterious side effects and usually inexpensive. Curcumin, a component of turmeric (Curcuma longa), is one such agent that is safe, affordable, and efficacious. How curcumin kills tumor cells is the focus of this review. We show that curcumin modulates growth of tumor cells through regulation of multiple cell signaling pathways including cell proliferation pathway (cyclin D1, c-myc), cell survival pathway (Bcl-2, Bcl-xL, cFLIP, XIAP, c-IAP1), caspase activation pathway (caspase-8, 3, 9), tumor suppressor pathway (p53, p21) death receptor pathway (DR4, DR5), mitochondrial pathways, and protein kinase pathway (JNK, Akt, and AMPK). How curcumin selectively kills tumor cells, and not normal cells, is also described in detail. |
nfcorpus-qrel-MED-2606 | Generate text that best answers this question: carcinogens | Effect of turmeric on urinary mutagens in smokers.
Curcumin, the active principle of turmeric, is known to act as an anti-oxidant, anti-mutagen and anti-carcinogen in experimental animals. In the present study, anti-mutagenic effects of turmeric were assessed in 16 chronic smokers. It was observed that turmeric, given in doses of 1.5 g/day for 30 days, significantly reduced the urinary excretion of mutagens in smokers. In contrast, in six non-smokers, who served as control, there was no change in the urinary excretion of mutagens after 30 days. Turmeric had no significant effect on serum aspartate aminotransferase and alanine aminotransferase, blood glucose, creatinine and lipid profile. These results indicate that dietary turmeric is an effective anti-mutagen and it may be useful in chemoprevention. |
nfcorpus-qrel-MED-2608 | Generate text that best answers this question: carcinogens | In vitro antimutagenicity of curcumin against environmental mutagens.
The effects of curcumin, the yellow pigment of the spice, turmeric (Curcuma longa) on the mutagenicity of several environmental mutagens were investigated in the Salmonella/microsome test with or without Aroclor 1254-induced rat-liver homogenate (S-9 mix). With Salmonella typhimurium strain TA98 in the presence of S-9 mix, curcumin inhibited the mutagenicity of bidi and cigarette smoke condensates, tobacco and masheri extracts, benzo[a]pyrne and dimethyl benzo[a]anthracene in a dose-dependent manner. Curcumin did not influence the mutagenicity without S-9 mix of sodium azide, monoacetylhydrazine and streptozocin in strain TA100 nor of 4-nitrophenylenediamine in strain TA98. Our observations indicate that curcumin may alter the metabolic activation and detoxification of mutagens. |
nfcorpus-qrel-MED-2816 | Generate text that best answers this question: carcinogens | Plant-derived health: the effects of turmeric and curcuminoids.
Plants contain numerous polyphenols, which have been shown to reduce inflammation and hereby to increase resistance to disease. Examples of such polyphenols are isothiocyanates in cabbage and broccoli, epigallocatechin in green tee, capsaicin in chili peppers, chalones, rutin and naringenin in apples, resveratrol in red wine and fresh peanuts and curcumin/curcuminoids in turmeric. Most diseases are maintained by a sustained discreet but obvious increased systemic inflammation. Many studies suggest that the effect of treatment can be improved by a combination of restriction in intake of proinflammatory molecules such as advanced glycation end products (AGE), advanced lipoperoxidation end products (ALE), and rich supply of antiinflammatory molecules such as plant polyphenols. To the polyphenols with a bulk of experimental documentation belong the curcuminoid family and especially its main ingredient, curcumin. This review summarizes the present knowledge about these turmericderived ingredients, which have proven to be strong antioxidants and inhibitors of cyclooxigenase-2 (COX-2), lipoxygenase (LOX) and nuclear factor kappa B (NF-kappaB) but also AGE. A plethora of clinical effects are reported in various experimental diseases, but clinical studies in humans are few. It is suggested that supply of polyphenols and particularly curcuminoids might be value as complement to pharmaceutical treatment, but also prebiotic treatment, in conditions proven to be rather therapy-resistant such as Crohn's, long-stayed patients in intensive care units, but also in conditions such as cancer, liver cirrhosis, chronic renal disease, chronic obstructive lung disease, diabetes and Alzheimer's disease. |
nfcorpus-qrel-MED-4551 | Generate text that best answers this question: carcinogens | Maternal meat and fat consumption during pregnancy and suspected atopic eczema in Japanese infants aged 3-4 months: the Osaka Maternal and Child He...
Interest has increased in the possibility that maternal dietary intake during pregnancy might influence the development of allergic disorders in children. The present prospective study examined the association of maternal intake of selected foods high in fatty acids and specific types of fatty acids during pregnancy with the risk of suspected atopic eczema among Japanese infants aged 3-4 months. Subjects were 771 mother-child pairs. Information on maternal dietary intake during pregnancy was assessed with a validated self-administered diet history questionnaire. The term 'suspected atopic eczema' was used to define an outcome based on results of our questionnaire completed by mothers 3-4 months postpartum. The risk of suspected atopic eczema was 8.4% (n = 65). Higher maternal intake of meat during pregnancy was significantly associated with an increased risk of suspected atopic eczema in the offspring: the multivariate odds ratio (OR) for the highest vs. lowest quartile was 2.59 [95% confidence interval (CI): 1.15-6.17, p for trend = 0.01]. The positive association was strengthened when the definition of the outcome was confined to a definite physician's diagnosis of atopic eczema (n = 35): the multivariate OR between extreme quartiles was 3.53 (95% CI: 1.19-12.23, p for trend = 0.02). No material exposure-response relationships were observed between maternal intake of eggs, dairy products, fish, total fat, saturated fatty acids, monounsaturated fatty acids, n-3 polyunsaturated fatty acids, alpha-linolenic acid, eicosapentaenoic acid, docosahexaenoic acid, n-6 polyunsaturated fatty acids, linoleic acid, arachidonic acid and cholesterol and the ratio of n-3 to n-6 polyunsaturated fatty acid consumption and the risk of suspected atopic eczema. Higher maternal meat intake may increase the risk of infantile atopic eczema, whereas we found no evidence that maternal intake of fish and n-3 polyunsaturated fatty acids are preventive against infantile atopic eczema. (c) 2009 John Wiley & Sons A/S |
nfcorpus-qrel-MED-2643 | Generate text that best answers this question: carcinogens | Endocrine-Disrupting Chemicals: Associated Disorders and Mechanisms of Action
The incidence and/or prevalence of health problems associated with endocrine-disruption have increased. Many chemicals have endocrine-disrupting properties, including bisphenol A, some organochlorines, polybrominated flame retardants, perfluorinated substances, alkylphenols, phthalates, pesticides, polycyclic aromatic hydrocarbons, alkylphenols, solvents, and some household products including some cleaning products, air fresheners, hair dyes, cosmetics, and sunscreens. Even some metals were shown to have endocrine-disrupting properties. Many observations suggesting that endocrine disruptors do contribute to cancer, diabetes, obesity, the metabolic syndrome, and infertility are listed in this paper. An overview is presented of mechanisms contributing to endocrine disruption. Endocrine disruptors can act through classical nuclear receptors, but also through estrogen-related receptors, membrane-bound estrogen-receptors, and interaction with targets in the cytosol resulting in activation of the Src/Ras/Erk pathway or modulation of nitric oxide. In addition, changes in metabolism of endogenous hormones, cross-talk between genomic and nongenomic pathways, cross talk with estrogen receptors after binding on other receptors, interference with feedback regulation and neuroendocrine cells, changes in DNA methylation or histone modifications, and genomic instability by interference with the spindle figure can play a role. Also it was found that effects of receptor activation can differ in function of the ligand. |
nfcorpus-qrel-MED-2645 | Generate text that best answers this question: carcinogens | Reduction in penis size and plasma testosterone concentrations in juvenile alligators living in a contaminated environment.
The development of the male reproductive ducts and external genitalia in vertebrates is dependent on elevated androgen concentrations during embryonic development and the period of postnatal growth. We have observed that a population of juvenile alligators living on Lake Apopka exhibit significantly smaller penis size (24% average decrease) and lower plasma concentrations of testosterone (70% lower concentrations) when compared to animals of similar size on Lake Woodruff. In addition to smaller phalli, no relationship exists between plasma testosterone concentrations and penile size in males from Lake Apopka, whereas a positive relationship exists for males from Lake Woodruff. The alligators on Lake Apopka are known to have elevated concentrations of the antiandrogenic DDT breakdown product p.p'-DDE stored in their fat. We suggest a number of hypotheses that could explain the modification in the phenotype of the juvenile male living in Lake Apopka. These modifications in phenotype include a smaller penis size, lower plasma androgen concentrations, and lack of responsiveness of the penis to the plasma androgens present. |
nfcorpus-qrel-MED-2656 | Generate text that best answers this question: carcinogens | Effects of intestinal microflora and the environment on the development of asthma and allergy.
The aim of previous research into the causes of allergic diseases, including asthma was mostly to identify potential risk factors in the environment. No major risk factors have been identified, however. Over the past 10 years, focus has, therefore, more been directed towards protective factors that could enhance the development of tolerance to allergens which were previously encountered early in life, but are now lost in modern affluent societies. In particular, the role of childhood infections has been discussed, but so far these studies have not been conclusive. Recent epidemiological studies and experimental research suggest that the microbial environment and exposure to microbial products in infancy modifies immune responses and enhances the development of tolerance to ubiquitous allergens. The intestinal microflora may play a particular role in this respect, as it is the major external driving force in the maturation of the immune system after birth, and animal experiments have shown it to be a prerequisite for normal development of oral tolerance. Recent studies have shown differences in the composition of the microflora between healthy and allergic infants in countries with a high and low prevalence of allergies and between healthy and allergic infants within such countries. These differences are apparent within the first week of life and thus precede clinical symptoms. The use of live microorganisms that might be beneficial to health has a long tradition and the safety is well documented. Very recently, several prospective intervention studies, modifying the gut flora from birth have yielded encouraging results and may suggest a new mode of primary prevention of allergy in the future. |
nfcorpus-qrel-MED-2657 | Generate text that best answers this question: carcinogens | Increasing prevalence of Japanese cedar pollinosis: a meta-regression analysis.
BACKGROUND: Japanese cedar pollinosis, caused by the pollen of the Japanese cedar tree (Cryptomeria japonica), is the commonest seasonal allergic disease in Japan. A number of epidemiological surveys have been reported on Japanese cedar pollinosis, but it has never been assessed systematically or quantitatively. To confirm the increasing prevalence of Japanese cedar pollinosis and related factors, we conducted a meta-regression analysis on population-based surveys in Japan. METHODS: We searched for data from population-based surveys in which serological methods were used to test all participants. Weighted regression of logit-transformed prevalence and sensitization rates were used to evaluate the effects of the year of survey, age, and degree of urbanization. We also analyzed the relationship between prevalence and sensitization rate. RESULTS: Thirty-eight reports with 27 subgroups for prevalence and 134 subgroups for sensitization rate were selected from the literature published in the years between 1986 and 2000. The Japanese cedar pollen sensitization rate was found to be significantly correlated with the year of survey, age, and degree of urbanization (adjusted R(2) = 0.55). The coefficient for the correlation between the prevalence and the sensitization rate revealed a statistically significant correlation (Pearson's r = 0.70, p < 0.001). CONCLUSIONS: The prevalence of Japanese cedar pollinosis among adolescents was predicted to be 28.7% in metropolitan areas and 24.5% in the general population in urban areas in the year 2004, derived from the estimated sensitization rate and the relationship between sensitization rate and prevalence. The prevalence of Japanese cedar pollinosis increased 2.6-fold between 1980 and 2000, and the prevalence differed considerably according to age and degree of urbanization. Copyright (c) 2005 S. Karger AG, Basel |
nfcorpus-qrel-MED-2658 | Generate text that best answers this question: carcinogens | Alkylphenols--potential modulators of the allergic response.
The prevalence of allergic diseases has increased in recent decades. Allergic diseases, particularly asthma, are complex diseases with strong gene-environment interactions. Epidemiological studies have identified a variety of risk factors for the development of allergic diseases. Among them, endocrine-disrupting chemicals (EDCs) play an important role in triggering or exacerbating these diseases. 4-Nonylphenol (NP) and 4-octylphenol (OP)--two major alkylphenols--have been recognized as common toxic and xenobiotic endocrine disrupters. Due to their low solubility, high hydrophobicity, and low estrogenic activity, they tend to accumulate in the human body and may be associated with the adverse effects of allergic diseases. Recently, new evidence has supported the importance of alkylphenols in the in vitro allergic response. This review focuses on the effects of alkylphenols on several key cell types in the context of allergic inflammation. Copyright © 2012. Published by Elsevier B.V. |
nfcorpus-qrel-MED-2660 | Generate text that best answers this question: carcinogens | Trends in nutritional intake and serum cholesterol levels over 40 years in Tanushimaru, Japanese men.
BACKGROUND: Rapid socioeconomic development in Japan since the beginning of the Seven Countries Study in 1958 has brought remarkable changes in lifestyle and dietary patterns. We investigated the relationship between time trends in nutrient intake and serum cholesterol levels in a Japanese cohort of the Seven Countries Study, in Tanushimaru, a typical farming town on Kyushu Island. METHODS: Subjects totaled 628 in 1958, 539 in 1977, 602 in 1982, 752 in 1989, and 402 in 1999, and all of the subjects were men aged 40-64 years. Eating patterns were evaluated by 24-hour dietary recall from 1958 through 1989, and by a food frequency questionnaire in 1999. We also measured serum cholesterol levels in each health examination. RESULTS: The total daily energy intake decreased from 2837 kcal in 1958 to 2202 kcal in 1999. The carbohydrate intake in percentage of total daily energy intake decreased markedly, from 84% in 1958 to 62% in 1999, in contrast to large increases during this period in protein intake (from 11% to 18%) and fat intake (from 5% to 20%). In proportion to the dramatic change in protein and fat intake, serum cholesterol levels showed large increases (from 152.5mg/dl to 194.2 mg/ dL). CONCLUSIONS: In spite of such big dietary changes toward a westernized diet, the incidence of coronary artery disease in a rural Japanese area remains low. However, careful surveillance is needed in the future because of the remarkably increasing intake of fats, especially saturated fatty acids. |
nfcorpus-qrel-MED-2649 | Generate text that best answers this question: carcinogens | Dietary meat and fat intake and prevalence of rhinoconjunctivitis in pregnant Japanese women: baseline data from the Kyushu Okinawa Maternal and Child Health Study
Background Dietary fat exerts numerous complex effects on proinflammatory and immunologic pathways. Several epidemiological studies have examined the relationships between intake of fatty acids and/or foods high in fat and allergic rhinitis, but have provided conflicting findings. The current cross-sectional study investigated such relationships in Japan. Methods Study subjects were 1745 pregnant women. The definition of rhinoconjunctivitis was based on criteria from the International Study of Asthma and Allergies in Childhood. Information on dietary factors was collected using a validated self-administered diet history questionnaire. Adjustment was made for age; gestation; region of residence; number of older siblings; number of children; smoking; secondhand smoke exposure at home and at work; family history of asthma, atopic eczema, and allergic rhinitis; household income; education; and body mass index. Results The prevalence of rhinoconjunctivitis in the past 12 months was 25.9%. Higher meat intake was significantly associated with an increased prevalence of rhinoconjunctivitis: the adjusted odds ratio between extreme quartiles was 1.71 (95% confidence interval: 1.25-2.35, P for trend = 0.002). No measurable association was found between fish intake and rhinoconjunctivitis. Intake of total fat, saturated fatty acids, monounsaturated fatty acids, n-3 polyunsaturated fatty acids, α-linolenic acid, eicosapentaenoic acid, docosahexaenoic acid, n-6 polyunsaturated fatty acids, linoleic acid, arachidonic acid, and cholesterol and the ratio of n-3 to n-6 polyunsaturated fatty acid intake were not evidently related to the prevalence of rhinoconjunctivitis. Conclusions The current results suggest that meat intake may be positively associated with the prevalence of rhinoconjunctivitis in young adult Japanese women. |
nfcorpus-qrel-MED-2675 | Generate text that best answers this question: carcinogens | Comparison of the cytotoxic and mutagenic potential of liquid smoke food flavourings, cigarette smoke condensate and wood smoke condensate.
Although products of pyrolysis are often cytotoxic and mutagenic, the relationship between the type of material pyrolysed and the toxicity of the resulting pyrolysis products is poorly understood. The objective of this study was to evaluate and compare the cytotoxicity and mutagenicity of several types of common pyrolysis products. The cytotoxicity and mutagenicity of these products were assessed by using neutral red uptake and Ames mutagenicity assays, respectively. The biological activities of four liquid smoke food flavourings (LSF) were compared with two other pyrolysis-derived materials; cigarette smoke condensate (CSC) and a wood smoke condensate (WSC). Results indicated all of the mixtures exhibited a concentration-dependent cytotoxic response. The CSC and WSC were less cytotoxic than three of the LSFs, but more cytotoxic than one of the brands. The CSC was mutagenic in two Salmonella strains; however, none of the LSFs or WSC was mutagenic using TA98, and only three of the LSFs were positive with TA100. The six pyrolysis-derived materials evaluated in this study showed differing patterns and magnitudes of cytotoxicity and mutagenicity. These results indicate that the cytotoxicity and mutagenicity of complex mixtures derived from pyrolysis products are affected by the type of material pyrolysed and/or the method used to prepare the mixture. The cytotoxic potential of some commercial smoke flavourings is greater than cigarette smoke condensate and several of the food flavourings are mutagenic in one Salmonella strain. |
nfcorpus-qrel-MED-2676 | Generate text that best answers this question: carcinogens | Mutagenicity testing in the Salmonella typhimurium assay of phenolic compounds and phenolic fractions obtained from smokehouse smoke condensates.
Smokehouse smoke, which is used for flavouring meat products, was investigated for its mutagenic activity in the Salmonella typhimurium assay. We were chiefly concerned with the fractions free of polycyclic aromatic hydrocarbons but containing phenol compounds, which are responsible for the preservative and aromatizing properties of the smoke. The most abundantly occurring phenol compounds (phenol, cresols, 2,4-dimethylphenol, brenzcatechine, syringol, eugenol, vanilline and guaiacol) gave negative results when they were tested for mutagenicity at five concentrations up to 5000 micrograms/plate, with and without S-9 mix, using five strains of S. typhimurium. Even when phenol was further investigated in a variety of test conditions, no induction of his+ revertants was observed. When smokehouse smoke was condensed and fractionated the majority of the various phenolic fractions also gave negative results when tested at five concentrations using five strains of S. typhimurium. However there was a slight increase in the number of revertants in a few cases. The presence in the phenolic fractions of very small amounts of mutagenic impurities, the nature of which needs further investigation, cannot be excluded. These results support the further development of non-hazardous smoke-aroma preparations, based on the phenolic components of smokehouse smoke. |
nfcorpus-qrel-MED-2677 | Generate text that best answers this question: carcinogens | Biological Clues to Potent DNA-Damaging Activities in Food and Flavoring
Population differences in age-related diseases and cancer could stem from differences in diet. To characterize DNA strand-breaking activities in selected foods/beverages, flavorings, and some of their constituent chemicals, we used p53R cells, a cellular assay sensitive to such breaks. Substances testing positive included reference chemicals: quinacrine (peak response, 51X) and etoposide (33X); flavonoids: EGCG (19X), curcumin (12X), apigenin (9X), and quercetin (7X); beverages: chamomile (11X), green (21X), and black tea (26X) and coffee (3 to 29X); and liquid smoke (4 to 28X). Damage occurred at dietary concentrations: etoposide near 5 μg/ml produced responses similar to a 1:1000 dilution of liquid smoke, a 1:20 dilution of coffee, and a 1:5 dilution of tea. Pyrogallol-related chemicals and tannins are present in dietary sources and individually produced strong activity: pyrogallol (30X), 3-methoxycatechol (25X), gallic acid (21X), and 1,2,4-benzenetriol (21X). From structure-activity relationships, high activities depended on specific orientations of hydroxyls on the benzene ring. Responses accompanied cellular signals characteristic of DNA breaks such as H2AX phosphorylation. Breaks were also directly detected by comet assay. Cellular toxicological effects of foods and flavorings could guide epidemiologic and experimental studies of potential disease risks from DNA strand-breaking chemicals in diets. |
nfcorpus-qrel-MED-2678 | Generate text that best answers this question: carcinogens | Polycyclic aromatic hydrocarbons in smoked food products and commercial liquid smoke flavourings.
Smoked foods including turkey, pork, chicken, beef and fish products were screened for the presence of carcinogenic and non-carcinogenic polycyclic aromatic hydrocarbons (PAHs). Eighteen commercial liquid smoke flavourings and seasonings were also analysed. Total PAH concentrations in smoked meat products ranged from 2.6 micrograms/kg in a cooked ham sample to 29.8 micrograms/kg in grilled pork chops, while those in fish products ranged from 9.3 micrograms/kg in smoked shrimp to 86.6 micrograms/kg in smoked salmon. Total concentrations of the carcinogenic PAHs (benzo[a]anthracene, benzo[b]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, and indeno[1,2,3-c,d]pyrene) ranged from non-detectable in several meat products to 7.4 micrograms/kg in grilled pork chops, and from 0.2 micrograms/kg in trout to 16.0 micrograms/kg in salmon. In liquid smoke flavourings and seasonings, total PAH concentrations ranged from 6.3 to 43.7 micrograms/kg, with the carcinogenic PAHs ranging from 0.3 to 10.2 micrograms/kg. |
nfcorpus-qrel-MED-2679 | Generate text that best answers this question: carcinogens | Commercial hickory-smoke flavouring is a human lymphoblast mutagen but does not induce lung adenomas in newborn mice.
Commercial aqueous wood-smoke flavouring induced significant increases in the 6-thioguanine resistance mutation frequency of TK6 human lymphoblasts at 0.1 microliter flavouring/ml of cell suspension. This corresponds to 6 micrograms/ml of dissolved 'solids' as determined by fully drying the aqueous flavouring in a vacuum desiccator. In AHH-1 human lymphoblasts, which contain a cytochrome P-450 monooxygenase system, mutations were induced at 0.3 microliter/ml, corresponding to 18 microliters/ml of dissolved 'solids'. The flavouring did not induce 8-azaguanine resistant mutations in Salmonella typhimurium at concentrations up to 1.5 microliter/ml. At higher concentrations the flavouring was toxic to bacteria. The flavouring did not induce lung adenomas or other tumours in newborn mice when injected ip with total doses of up to 26 microliters over a 3-wk period. Toxicity to the kidney, colon and rectum was observed in some mice at 15 wk of age. |
nfcorpus-qrel-MED-2992 | Generate text that best answers this question: carcinogens | TOXICITY AND CARCINOGENICITY STUDIES OF 4-METHYLIMIDAZOLE IN F344/N RATS AND B6C3F1 MICE
4-Methylimidazole (4MI) is used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, cleaning and agricultural chemicals, and rubber. It has been identified as a by-product of fermentation in foods and has been detected in mainstream and side stream tobacco smoke. 4MI was studied because of its high potential for human exposure. Groups of 50 male and 50 female F344/N rats were fed diets containing 0-, 625-, 1,250-, or 2,500-ppm 4MI (males) or 0-, 1,250-, 2,500-, or 5,000-ppm 4MI (females) for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 30, 55, or 115 mg 4MI/kg body weight to males and 60, 120, or 250 mg 4MI/kg to females. Survival of all exposed groups of males and females was similar to that of the control groups. Mean body weights of males in the 1,250- and 2,500-ppm groups and females in the 2,500- and 5,000-ppm groups were less than those of the control groups throughout the study. Feed consumption by 5,000-ppm females was less than that by the controls. Clonic seizures, excitability, hyperactivity, and impaired gait were observed primarily in 2,500- and 5,000-ppm females. The incidence of mononuclear cell leukemia in the 5,000-ppm females was significantly greater than that in the controls. The incidences of hepatic histiocytosis, chronic inflammation, and focal fatty change were significantly increased in all exposed groups of male and female rats. The incidences of hepatocellular eosinophilic and mixed cell foci were significantly increased in 2,500-ppm males and 5,000-ppm females. Groups of 50 male and 50 female B6C3F1 mice were fed diets containing 0-, 312-, 625-, or 1,250-ppm 4MI for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 40, 80, or 170 mg 4MI/kg body weight to males and females. Survival of all exposed groups of males and females was similar to that of the control groups. Mean body weights of males and females in the 1,250-ppm groups and that in the 312- and 625-ppm females were less than those of the control groups. Feed consumption by exposed groups of male and female mice was similar to that by the controls. The incidences of alveolar/bronchiolar adenoma in all exposed groups of females, alveolar/bronchiolar carcinoma in 1,250-ppm males, and alveolar/bronchiolar adenoma or carcinoma (combined) in 1,250-ppm males and 625- and 1,250-ppm females were significantly greater than those in the control groups. The incidence of alveolar epithelial hyperplasia was significantly increased in the 1,250-ppm females. 4MI is carcinogenic inducing alveolar/bronchiolar adenoma and carcinoma in male and female mice. 4MI may also induce mononuclear cell leukemia in female rats. |
nfcorpus-qrel-MED-2994 | Generate text that best answers this question: carcinogens | Carcinogenicity and regulation of caramel colorings.
2- and 4-methylimidazoles are present as contaminants in caramel colorings manufactured with ammonia catalysts. Both contaminants have been shown to induce cancer in animals and may be present in caramel colorings in amounts that exceed federal guidelines. California requires warning notices on products that could lead to consumption of more than 30 micrograms per day. The US Food and Drug Administration should bar the use of excessively contaminated caramel coloring in food. |
nfcorpus-qrel-MED-3781 | Generate text that best answers this question: carcinogens | Detection of increased choline compounds with proton nuclear magnetic resonance spectroscopy subsequent to malignant transformation of human prosta...
In this study, a panel of normal human prostate cells (HPCs) and tumor cells derived from metastases were studied by (1)H NMR spectroscopy to determine whether the malignant transformation of HPCs results in the elevation of choline compounds. Although an elevated choline signal has been observed previously in clinical studies, the contribution of the different Cho compounds to this elevation, as well as their quantification, has not been established until now. Here we have shown that HPCs derived from metastases exhibit significantly higher phosphocholine as well as glycerophosphocholine levels compared with normal prostate epithelial and stromal cells. Thus the elevation of the choline peak observed clinically in prostate cancer is attributable to an alteration of phospholipid metabolism and not simply to increased cell density, doubling time, or other nonspecific effects. Androgen deprivation of the androgen receptor-positive cell lines resulted in a significant increase of choline compounds after chronic androgen deprivation of the LNCaP cell line and in a decrease of choline compounds after a more acute androgen deprivation of the LAPC-4 cell line. These data strongly support the use of proton magnetic resonance spectroscopic imaging to detect the presence of prostate cancer for diagnosis, to detect response subsequent to androgen ablation therapy, and to detect recurrence. |
nfcorpus-qrel-MED-3789 | Generate text that best answers this question: carcinogens | Choline intake and risk of lethal prostate cancer: incidence and survival
Background: Meat, milk, and eggs have been inconsistently associated with the risk of advanced prostate cancer. These foods are sources of choline—a nutrient that may affect prostate cancer progression through cell membrane function and one-carbon metabolism. No study has examined dietary choline and the risk of lethal prostate cancer. Objective: Our objective was to examine whether dietary choline, choline-containing compounds, and betaine (a choline metabolite) increase the risk of lethal prostate cancer. Design: We prospectively examined the intake of these nutrients and the risk of lethal prostate cancer among 47,896 men in the Health Professionals Follow-Up Study. In a case-only survival analysis, we examined the postdiagnostic intake of these nutrients and the risk of lethal prostate cancer among 4282 men with an initial diagnosis of nonmetastatic disease during follow-up. Diet was assessed with a validated questionnaire 6 times during 22 y of follow-up. Results: In the incidence analysis, we observed 695 lethal prostate cancers during 879,627 person-years. Men in the highest quintile of choline intake had a 70% increased risk of lethal prostate cancer (HR: 1.70; 95% CI: 1.18, 2.45; P-trend = 0.005). In the case-only survival analysis, we observed 271 lethal cases during 33,679 person-years. Postdiagnostic choline intake was not statistically significantly associated with the risk of lethal prostate cancer (HR for quintile 5 compared with quintile 1: 1.69; 95% CI: 0.93, 3.09; P-trend = 0.20). Conclusion: Of the 47,896 men in our study population, choline intake was associated with an increased risk of lethal prostate cancer. |
nfcorpus-qrel-MED-3790 | Generate text that best answers this question: carcinogens | Intakes of meat, fish, poultry, and eggs and risk of prostate cancer progression
Background: Processed meat and fish have been shown to be associated with the risk of advanced prostate cancer, but few studies have examined diet after prostate cancer diagnosis and risk of its progression. Objective: We examined the association between postdiagnostic consumption of processed and unprocessed red meat, fish, poultry, and eggs and the risk of prostate cancer recurrence or progression. Design: We conducted a prospective study in 1294 men with prostate cancer, without recurrence or progression as of 2004–2005, who were participating in the Cancer of the Prostate Strategic Urologic Research Endeavor and who were followed for an average of 2 y. Results: We observed 127 events (prostate cancer death or metastases, elevated prostate-specific antigen concentration, or secondary treatment) during 2610 person-years. Intakes of processed and unprocessed red meat, fish, total poultry, and skinless poultry were not associated with prostate cancer recurrence or progression. Greater consumption of eggs and poultry with skin was associated with 2-fold increases in risk in a comparison of extreme quantiles: eggs [hazard ratio (HR): 2.02; 95% CI: 1.10, 3.72; P for trend = 0.05] and poultry with skin (HR: 2.26; 95% CI: 1.36, 3.76; P for trend = 0.003). An interaction was observed between prognostic risk at diagnosis and poultry. Men with high prognostic risk and a high poultry intake had a 4-fold increased risk of recurrence or progression compared with men with low/intermediate prognostic risk and a low poultry intake (P for interaction = 0.003). Conclusions: Our results suggest that the postdiagnostic consumption of processed or unprocessed red meat, fish, or skinless poultry is not associated with prostate cancer recurrence or progression, whereas consumption of eggs and poultry with skin may increase the risk. |
nfcorpus-qrel-MED-3782 | Generate text that best answers this question: carcinogens | Egg, red meat, and poultry intake and risk of lethal prostate cancer in the prostate specific antigen-era: incidence and survival
Red and processed meat may increase risk of advanced prostate cancer. Data on post-diagnostic diet and prostate cancer are sparse, but post-diagnostic intake of poultry with skin and eggs may increase risk of disease progression. Therefore, we prospectively examined total, unprocessed, and processed red meat, poultry, and eggs in relation to risk of lethal prostate cancer (e.g. men without cancer at baseline who developed distant organ metastases or died from prostate cancer during follow-up) among 27, 607 men followed from 1994–2008. We also performed a case-only survival analysis to examine post-diagnostic consumption of these foods and risk of lethal prostate cancer among the 3,127 men initially diagnosed with non-metastatic prostate cancer during follow-up. In the incidence analysis, we observed 199 events during 306,715 person-years. Men who consumed 2.5 or more eggs per week had an 81% increased risk of lethal prostate cancer compared to men who consumed less than 0.5 eggs per week (HR: 1.81; 95% confidence interval (CI): 1.13, 2.89; p-trend: 0.01). In the case-only survival analysis, we observed 123 events during 19,354 person-years. There were suggestive, but not statistically significant, positive associations between post-diagnostic poultry (HR ≥3.5 vs. <1.5 servings per week: 1.69; 95%CI: 0.96, 2.99; p-trend: 0.07) and post-diagnostic processed red meat (HR ≥3 vs. <0.5 servings per week: 1.45; 95%CI: 0.73, 2.87; p-trend: 0.08) and risk of progression of localized prostate cancer to lethal disease. In conclusion, consumption of eggs may increase risk of developing a lethal-form of prostate cancer among healthy men. |
nfcorpus-qrel-MED-3762 | Generate text that best answers this question: carcinogens | Moderate alcohol consumption during adult life, drinking patterns, and breast cancer risk
Context Multiple studies have linked alcohol consumption to breast cancer risk, but the risk of lower levels of consumption has not been well quantified. In addition, the role of drinking patterns (i.e. frequency of drinking and “binge” drinking) and consumption at different times of adult life are not well understood. Objective To evaluate the association of breast cancer with alcohol consumption during adult life, including quantity, frequency, and age at consumption. Design, Setting, and Participants Prospective observational study of 105,986 women enrolled in the Nurses’ Health Study followed from 1980 until 2008 with early adult and eight updated alcohol assessments during this time. Main Outcome Measures Relative risks of developing invasive breast cancer. Results 7690 cases developed during 2.4 million person-years of follow-up. Increasing alcohol consumption was associated with increased breast cancer risk that was statistically significant at levels as low as 5.0-9.9 gm/day, equivalent to 3-6 drinks/week (RR 1.15 (95% CI 1.06-1.24) 332 cases/100,000 person-years). After controlling for cumulative alcohol intake, binge drinking, but not frequency of drinking, was associated with breast cancer risk. Alcohol intake both earlier and later in adult life was independently associated with risk. Conclusion Low levels of alcohol consumption were associated with a small increase in breast cancer risk, with the most consistent measure being cumulative alcohol intake throughout adult life. Alcohol intake both earlier and later in adult life was independently associated with risk. |
nfcorpus-qrel-MED-3763 | Generate text that best answers this question: carcinogens | A single sip of a strong alcoholic beverage causes exposure to carcinogenic concentrations of acetaldehyde in the oral cavity.
The aim of this study was to explore oral exposure to carcinogenic (group 1) acetaldehyde after single sips of strong alcoholic beverages containing no or high concentrations of acetaldehyde. Eight volunteers tasted 5 ml of ethanol diluted to 40 vol.% with no acetaldehyde and 40 vol.% calvados containing 2400 μM acetaldehyde. Salivary acetaldehyde and ethanol concentrations were measured by gas chromatography. The protocol was repeated after ingestion of ethanol (0.5 g/kg body weight). Salivary acetaldehyde concentration was significantly higher after sipping calvados than after sipping ethanol at 30s both with (215 vs. 128 μmol/l, p<0.05) and without (258 vs. 89 μmol/l, p<0.05) alcohol ingestion. From 2 min onwards there were no significant differences in the decreasing salivary acetaldehyde concentration, which remained above the level of carcinogenicity still at 10 min. The systemic alcohol distribution from blood to saliva had no additional effect on salivary acetaldehyde after sipping of the alcoholic beverages. Carcinogenic concentrations of acetaldehyde are produced from ethanol in the oral cavity instantly after a small sip of strong alcoholic beverage, and the exposure continues for at least 10 min. Acetaldehyde present in the beverage has a short-term effect on total acetaldehyde exposure. Copyright © 2011 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-3764 | Generate text that best answers this question: carcinogens | Salivary acetaldehyde increase due to alcohol-containing mouthwash use: a risk factor for oral cancer.
Increasing evidence suggests that acetaldehyde, the first and genotoxic metabolite of ethanol, mediates the carcinogenicity of alcoholic beverages. Ethanol is also contained in a number of ready-to-use mouthwashes typically between 5 and 27% vol. An increased risk of oral cancer has been discussed for users of such mouthwashes; however, epidemiological evidence had remained inconclusive. This study is the first to investigate acetaldehyde levels in saliva after use of alcohol-containing mouthwashes. Ready-to-use mouthwashes and mouthrinses (n = 13) were rinsed in the mouth by healthy, nonsmoking volunteers (n = 4) as intended by the manufacturers (20 ml for 30 sec). Saliva was collected at 0.5, 2, 5 and 10 min after mouthwash use and analyzed using headspace gas chromatography. The acetaldehyde content in the saliva was 41 +/- 15 microM, range 9-85 microM (0.5 min), 52 +/- 14 microM, range 11-105 microM (2 min), 32 +/- 7 microM, range 9-67 microM (5 min) and 15 +/- 7 microM, range 0-37 microM (10 min). The contents were significantly above endogenous levels and corresponding to concentrations normally found after alcoholic beverage consumption. A twice-daily use of alcohol-containing mouthwashes leads to a systemic acetaldehyde exposure of 0.26 microg/kg bodyweight/day on average, which corresponds to a lifetime cancer risk of 3E-6. The margin of exposure was calculated to be 217,604, which would be seen as a low public health concern. However, the local acetaldehyde contents in the saliva are reaching concentrations associated with DNA adduct formation and sister chromatid exchange in vitro, so that concerns for local carcinogenic effects in the oral cavity remain. |
nfcorpus-qrel-MED-1139 | Generate text that best answers this question: carcinogens | Environmental exposure to pesticides and cancer risk in multiple human organ systems.
There is growing evidence on the association between long-term exposure to pesticides in occupational settings and an elevated rate of chronic diseases, including different types of cancer. However, data on non-occupational exposures are scarce to draw any conclusion. The objective of this study was to investigate the putative associations of environmental pesticide exposures in the general population with several cancer sites and to discuss potential carcinogenic mechanisms by which pesticides develop cancer. A population-based case-control study was conducted among people residing in 10 Health districts from Andalusia (South Spain) to estimate the risk of cancer at different sites. Health districts were categorized into areas of high and low environmental pesticide exposure based on two quantitative criteria: number of hectares devoted to intensive agriculture and pesticide sales per capita. The study population consisted of 34,205 cancer cases and 1,832,969 age and health district matched controls. Data were collected by computerized hospital records (minimum dataset) between 1998 and 2005. Prevalence rates and the risk of cancer at most organ sites were significantly higher in districts with greater pesticide use related to those with lower pesticide use. Conditional logistic regression analyses showed that the population living in areas with high pesticide use had an increased risk of cancer at all sites studied (odds ratios between 1.15 and 3.45) with the exception of Hodgkin's disease and non-Hodgkin lymphoma. The results of this study support and extend previous evidence from occupational studies indicating that environmental exposure to pesticides may be a risk factor for different types of cancer at the level of the general population. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved. |
nfcorpus-qrel-MED-1140 | Generate text that best answers this question: carcinogens | Organic food: buying more safety or just peace of mind? A critical review of the literature.
Consumer concern over the quality and safety of conventional food has intensified in recent years, and primarily drives the increasing demand for organically grown food, which is perceived as healthier and safer. Relevant scientific evidence, however, is scarce, while anecdotal reports abound. Although there is an urgent need for information related to health benefits and/or hazards of food products of both origins, generalized conclusions remain tentative in the absence of adequate comparative data. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives; yet, the significance of this difference is questionable, inasmuch as actual levels of contamination in both types of food are generally well below acceptable limits. Also, some leafy, root, and tuber organic vegetables appear to have lower nitrate content compared with conventional ones, but whether or not dietary nitrate indeed constitutes a threat to human health is a matter of debate. On the other hand, no differences can be identified for environmental contaminants (e.g. cadmium and other heavy metals), which are likely to be present in food from both origins. With respect to other food hazards, such as endogenous plant toxins, biological pesticides and pathogenic microorganisms, available evidence is extremely limited preventing generalized statements. Also, results for mycotoxin contamination in cereal crops are variable and inconclusive; hence, no clear picture emerges. It is difficult, therefore, to weigh the risks, but what should be made clear is that 'organic' does not automatically equal 'safe.' Additional studies in this area of research are warranted. At our present state of knowledge, other factors rather than safety aspects seem to speak in favor of organic food. |
nfcorpus-qrel-MED-1167 | Generate text that best answers this question: carcinogens | 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-qrel-MED-1142 | Generate text that best answers this question: carcinogens | Formation of dioxins during exposure of pesticide formulations to sunlight.
Chlorinated pesticides can contain impurities of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and their precursors, as a result of various manufacturing processes and conditions. As precursor formation of PCDD/Fs can also be mediated by ultraviolet light (UV), this study investigated whether PCDD/Fs are formed when currently used pesticides are exposed to natural sunlight. Formulations containing pentachloronitrobenzene (PCNB; n=2) and 2,4-dichlorophenoxyacetic acid (2,4-D; n=1) were exposed to sunlight in quartz tubes, and the concentration of 93 PCDD/F congeners were monitored over time. Considerable formation of PCDD/Fs was observed in both PCNB formulations (by up to 5600%, to a maximum concentration of 57000 μg ∑PCDD/F kg(-1)) as well as the 2,4-D formulation (by 3000%, to 140 μg ∑PCDD/F kg(-1)). TEQ also increased by up to 980%, to a maximum concentration of 28 μg kg(-1) in PCNB, but did not change in the 2,4-D formulation. Assuming similar yields as observed in the present study as a worst case scenario the use of PCNB in Australia may result in the formation of 155 g TEQ annum(-1), contributed primarily by OCDD formation. This warrants detailed evaluations on the contemporary release of PCDD/Fs to the environment after the use of pesticides. Changes in congener profiles (including the ratio of PCDDs to PCDFs (DF ratio)) suggest that pesticide sources of PCDD/Fs after sunlight exposure may not be recognized based on matching source fingerprints established from manufacturing impurities. These changes also provide preliminary insights into the possible formation routes and types of precursors involved. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1143 | Generate text that best answers this question: carcinogens | Risk perceptions and food choice: an exploratory analysis of organic- versus conventional-produce buyers.
Consumer choice between organically (without pesticides) and conventionally grown produce is examined. Exploratory focus-group discussions and questionnaires (N = 43) suggest that individuals who purchase organically grown produce believe it is substantially less hazardous than the conventional alternative and are willing to pay significant premiums to obtain it (a median 50% above the cost of conventional produce). The value of risk reduction implied by this incremental willingness to pay is not high relative to estimates for other risks, since the perceived risk reduction is relatively large. Organic-produce consumers also appear more likely than conventional-produce consumers to mitigate other ingestion-related risks (e.g., contaminated drinking water) but less likely to use automobile seatbelts. |
nfcorpus-qrel-MED-1144 | Generate text that best answers this question: carcinogens | Perceived risks of conventional and organic produce: pesticides, pathogens, and natural toxins.
Public risk perceptions and demand for safer food are important factors shaping agricultural production practices in the United States. Despite documented food safety concerns, little attempt has been made to elicit consumers' subjective risk judgments for a range of food safety hazards or to identify factors most predictive of perceived food safety risks. In this study, over 700 conventional and organic fresh produce buyers in the Boston area were surveyed for their perceived food safety risks. Survey results showed that consumers perceived relatively high risks associated with the consumption and production of conventionally grown produce compared with other public health hazards. For example, conventional and organic food buyers estimated the median annual fatality rate due to pesticide residues on conventionally grown food to be about 50 per million and 200 per million, respectively, which is similar in magnitude to the annual mortality risk from motor vehicle accidents in the United States. Over 90% of survey respondents also perceived a reduction in pesticide residue risk associated with substituting organically grown produce for conventionally grown produce, and nearly 50% perceived a risk reduction due to natural toxins and microbial pathogens. Multiple regression analyses indicate that only a few factors are consistently predictive of higher risk perceptions, including feelings of distrust toward regulatory agencies and the safety of the food supply. A variety of factors were found to be significant predictors of specific categories of food hazards, suggesting that consumers may view food safety risks as dissimilar from one another. Based on study findings, it is recommended that future agricultural policies and risk communication efforts utilize a comparative risk approach that targets a range of food safety hazards. |
nfcorpus-qrel-MED-1181 | Generate text that best answers this question: carcinogens | Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses
Demand for organic foods is partially driven by consumers' perceptions that they are more nutritious. However, scientific opinion is divided on whether there are significant nutritional differences between organic and non-organic foods, and two recent reviews have concluded that there are no differences. In the present study, we carried out meta-analyses based on 343 peer-reviewed publications that indicate statistically significant and meaningful differences in composition between organic and non-organic crops/crop-based foods. Most importantly, the concentrations of a range of antioxidants such as polyphenolics were found to be substantially higher in organic crops/crop-based foods, with those of phenolic acids, flavanones, stilbenes, flavones, flavonols and anthocyanins being an estimated 19 (95 % CI 5, 33) %, 69 (95 % CI 13, 125) %, 28 (95 % CI 12, 44) %, 26 (95 % CI 3, 48) %, 50 (95 % CI 28, 72) % and 51 (95 % CI 17, 86) % higher, respectively. Many of these compounds have previously been linked to a reduced risk of chronic diseases, including CVD and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies. Additionally, the frequency of occurrence of pesticide residues was found to be four times higher in conventional crops, which also contained significantly higher concentrations of the toxic metal Cd. Significant differences were also detected for some other (e.g. minerals and vitamins) compounds. There is evidence that higher antioxidant concentrations and lower Cd concentrations are linked to specific agronomic practices (e.g. non-use of mineral N and P fertilisers, respectively) prescribed in organic farming systems. In conclusion, organic crops, on average, have higher concentrations of antioxidants, lower concentrations of Cd and a lower incidence of pesticide residues than the non-organic comparators across regions and production seasons. |
nfcorpus-qrel-MED-1146 | Generate text that best answers this question: carcinogens | Estimation of cancer risks and benefits associated with a potential increased consumption of fruits and vegetables.
The current paper provides an analysis of the potential number of cancer cases that might be prevented if half the U.S. population increased its fruit and vegetable consumption by one serving each per day. This number is contrasted with an upper-bound estimate of concomitant cancer cases that might be theoretically attributed to the intake of pesticide residues arising from the same additional fruit and vegetable consumption. The cancer prevention estimates were derived using a published meta-analysis of nutritional epidemiology studies. The cancer risks were estimated using U.S. Environmental Protection Agency (EPA) methods, cancer potency estimates from rodent bioassays, and pesticide residue sampling data from the U.S. Department of Agriculture (USDA). The resulting estimates are that approximately 20,000 cancer cases per year could be prevented by increasing fruit and vegetable consumption, while up to 10 cancer cases per year could be caused by the added pesticide consumption. These estimates have significant uncertainties (e.g., potential residual confounding in the fruit and vegetable epidemiologic studies and reliance on rodent bioassays for cancer risk). However, the overwhelming difference between benefit and risk estimates provides confidence that consumers should not be concerned about cancer risks from consuming conventionally-grown fruits and vegetables. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1147 | Generate text that best answers this question: carcinogens | Cadmium in organic and conventional pig production.
The main sources of cadmium (Cd) input to soils have been phosphate fertilizers and deposition from air. In organic farming, phosphate fertilizers are not used, which may in the long term result in lower Cd levels. In the present study, feed, kidney, liver, and manure from growing/finishing pigs raised conventionally and organically on the same farm were microwave-digested and analyzed for Cd by graphite furnace atomic absorption spectrometry. Cd was also analyzed in soil and water. A quality control program was included. The organic pigs (n = 40) were raised outdoors and fed an organic feed; the conventional pigs (n = 40) were raised indoors and given a conventional feed. The Cd levels in organic and conventional feed were 39.9 microg/kg and 51.8 microg/kg, respectively. Organic feed contained 2% potato protein, which contributed 17% of the Cd content. Conventional feed contained 5% beet fiber, which contributed 38% of total Cd content. Both feeds contained vitamin-mineral mixtures with high levels of Cd: 991 microg/kg in organic and 589 microg/kg in conventional feed. There was a significant negative linear relationship between Cd concentration in kidney and kidney weight. There was no significant difference in liver Cd levels between organic and conventional pigs and the mean +/- SD was 15.4 +/- 3.0. In spite of the lower level of Cd in the organic feed, the organic pigs had significantly higher levels in kidneys than the conventional pigs, 96.1 +/- 19.5 microg/kg wet weight (mean +/- SD; n = 37) and 84.0 +/- 17.6 microg/kg wet weight (n = 40), respectively. Organic pigs had higher Cd levels in manure, indicating a higher Cd exposure from the environment, such as ingestion of soil. Differences in feed compositions and bioavailability of Cd from the feed components may also explain the different kidney levels of Cd. |
nfcorpus-qrel-MED-1763 | Generate text that best answers this question: carcinogens | The sensitivity of the child to sex steroids: possible impact of exogenous estrogens.
The current trends of increasing incidences of testis, breast and prostate cancers are poorly understood, although it is assumed that sex hormones play a role. Disrupted sex hormone action is also believed to be involved in the increased occurrence of genital abnormalities among newborn boys and precocious puberty in girls. In this article, recent literature on sex steroid levels and their physiological roles during childhood is reviewed. It is concluded that (i) circulating levels of estradiol in prepubertal children are lower than originally claimed; (ii) children are extremely sensitive to estradiol and may respond with increased growth and/or breast development even at serum levels below the current detection limits; (iii) no threshold has been established, below which no hormonal effects can be seen in children exposed to exogenous steroids or endocrine disruptors; (iv) changes in hormone levels during fetal and prepubertal development may have severe effects in adult life and (v) the daily production rates of sex steroids in children estimated by the Food and Drug Administration in 1999 and still used in risk assessments are highly overestimated and should be revised. Because no lower threshold for estrogenic action has been established, caution should be taken to avoid unnecessary exposure of fetuses and children to exogenous sex steroids and endocrine disruptors, even at very low levels. |
nfcorpus-qrel-MED-1592 | Generate text that best answers this question: carcinogens | Occurrence of estrogen hormones in biosolids, animal manure and mushroom compost.
The presence of natural estrogen hormones as trace concentrations in the environment has been reported by many researchers and is of growing concern due to its possible adverse effects on the ecosystem. In this study, municipal biosolids, poultry manure (PM) and cow manure (CM), and spent mushroom compost (SMC) were analyzed for the presence of seven estrogen hormones. 17α-estradiol, 17β-estradiol, 17α-dihydroequilin, and estrone were detected in the sampled biosolids and manures at concentrations ranging from 6 to 462 ng/g of dry solids. 17α-estradiol, 17β-estradiol, and estrone were also detected in SMC at concentrations ranging from 4 to 28 ng/g of dry solids. Desorption experiments were simulated in the laboratory using deionized water (milli-Q), and the aqueous phase was examined for the presence of estrogen hormones to determine their desorption potential. Very low desorption of 0.4% and 0.2% estrogen hormones was observed from municipal biosolids and SMC, respectively. An estimate of total estrogen contribution from different solid waste sources is reported. Animal manures (PM and CM) contribute to a significant load of estrogen hormones in the natural environment. |
nfcorpus-qrel-MED-1593 | Generate text that best answers this question: carcinogens | Oestrogen levels in serum and urine of premenopausal women eating low and high amounts of meat.
OBJECTIVE: Based on the hypothesis that high-meat diets may increase breast cancer risk through hormonal pathways, the present analysis compared oestrogens in serum and urine by meat-eating status. DESIGN: Intervention with repeated measures. SETTING: Two randomized soya trials (BEAN1 and BEAN2) among premenopausal healthy women. SUBJECTS: BEAN1 participants completed seven unannounced 24 h dietary recalls and donated five blood and urine samples over 2 years. BEAN2 women provided seven recalls and three samples over 13 months. Serum samples were analysed for oestrone (E₁) and oestradiol (E₂) using RIA. Nine oestrogen metabolites were measured in urine by LC-MS. Semi-vegetarians included women who reported consuming <30 g of red meat, poultry and fish daily, and pescatarians those who reported consuming <20 g of meat/poultry but >10 g of fish daily. All other women were classified as non-vegetarians. We applied mixed models to compute least-square means by vegetarian status adjusted for potential confounders. RESULTS: The mean age of the 272 participants was 41·9 (SD 4·5) years. Serum E₁ (85 v. 100 pg/ml, P = 0·04) and E₂ (140 v. 154 pg/ml, P = 0·04) levels were lower in the thirty-seven semi-vegetarians than in the 235 non-vegetarians. The sum of the nine urinary oestrogen metabolites (183 v. 200 pmol/mg creatinine, P = 0·27) and the proportions of individual oestrogens and pathways did not differ by meat-eating status. Restricting the models to the samples collected during the luteal phase strengthened the associations. CONCLUSIONS: Given the limitations of the study, the lower levels of serum oestrogens in semi-vegetarians than non-vegetarians need confirmation in larger populations. |
nfcorpus-qrel-MED-1594 | Generate text that best answers this question: carcinogens | Occurrence, fate, and biodegradation of estrogens in sewage and manure.
The estrogens estrone (E1), 17alpha-estradiol (E2alpha), 17beta-estradiol (E2beta), and estriol (E3) are natural sex hormones produced by humans and animals. In addition, there are some synthetic estrogens, such as 17alpha-ethinylestradiol (EE2), used for contraception purposes. These compounds are able to produce endocrine disruption in living organisms at nanogram-per-liter levels. In both humans and animals, estrogens are excreted in urine and feces, reaching the natural environment through discharge from sewage treatment plants (STP) and manure disposal units. In STPs, hormone removal depends on the type of treatment process and on different parameters such as the hydraulic and sludge retention times. Thus, hormone elimination rates vary from 0% to 90% in different STPs. Animals are also an important source of estrogens in the environment. Indeed, animals produce high concentrations of hormones which will end up in manure which is typically spread on land. Hence, waste-borne animal hormones may transfer these pollutants to the soil. The purpose of this review is to highlight the significance for both health and the environment of pollution by estrogens and critically review the existing knowledge on their fate and removal in different treatment processes. Relevant information on the microbial degradation of hormones and metabolic pathways is also included. |
nfcorpus-qrel-MED-1595 | Generate text that best answers this question: carcinogens | Development of an LC-MS/MS method to quantify sex hormones in bovine milk and influence of pregnancy in their levels.
Hormones work in harmony in the body, and this status must be maintained to avoid metabolic disequilibrium and the subsequent illness. Besides, it has been reported that exogenous steroids (presence in the environment and food products) influence the development of several important illnesses in humans. Endogenous steroid hormones in food of animal origin are unavoidable as they occur naturally in these products. The presence of hormones in food has been connected with several human health problems. Bovine milk contains considerable quantities of hormones and it is of particular concern. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, based on hydroxylamine derivatisation, has been developed and validated for the quantification of six sex hormones in milk [pregnenolone (P₅), progesterone (P₄), estrone (E₁), testosterone (T), androstenedione (A) and dehydroepiandrosterone (DHEA)]. This method has been applied to real raw milk samples and the existence of differences between milk from pregnant and non-pregnant cows has been statistically confirmed. Basing on a revision of existing published data, it could be concluded that maximum daily intakes for hormones are not reached through milk ingestion. Although dairy products are an important source of hormones, other products of animal origin must be considered as well for intake calculations. |
nfcorpus-qrel-MED-1596 | Generate text that best answers this question: carcinogens | Are oral contraceptives a significant contributor to the estrogenicity of drinking water?
Recent observed feminization of aquatic animals has raised concerns about estrogenic compounds in water supplies and the potential for these chemicals to reach drinking water. Public perception frequently attributes this feminization to oral contraceptives (OCs) in wastewater and raises concerns that exposure to OCs in drinking water may contribute to the recent rise in human reproductive problems. This paper reviews the literature regarding various sources of estrogens, in surface, source and drinking water, with an emphasis on the active molecule that comes from OCs. It includes discussion of the various agricultural, industrial, and municipal sources and outlines the contributions of estrogenic chemicals to the estrogenicity of waterways and estimates that the risk of exposure to synthetic estrogens in drinking water on human health is negligible. This paper also provides recommendations for strategies to better understand all the potential sources of estrogenic compounds in the environment and possibilities to reduce the levels of estrogenic chemicals in the water supply. |
nfcorpus-qrel-MED-1597 | Generate text that best answers this question: carcinogens | An Assessment of Potential Exposure and Risk from Estrogens in Drinking Water
Background Detection of estrogens in the environment has raised concerns in recent years because of their potential to affect both wildlife and humans. Objectives We compared exposures to prescribed and naturally occurring estrogens in drinking water to exposures to naturally occurring background levels of estrogens in the diet of children and adults and to four independently derived acceptable daily intakes (ADIs) to determine whether drinking water intakes are larger or smaller than dietary intake or ADIs. Methods We used the Pharmaceutical Assessment and Transport Evaluation (PhATE) model to predict concentrations of estrogens potentially present in drinking water. Predicted drinking water concentrations were combined with default water intake rates to estimate drinking water exposures. Predicted drinking water intakes were compared to dietary intakes and also to ADIs. We present comparisons for individual estrogens as well as combined estrogens. Results In the analysis we estimated that a child’s exposures to individual prescribed estrogens in drinking water are 730–480,000 times lower (depending upon estrogen type) than exposure to background levels of naturally occurring estrogens in milk. A child’s exposure to total estrogens in drinking water (prescribed and naturally occurring) is about 150 times lower than exposure from milk. Adult margins of exposure (MOEs) based on total dietary exposure are about 2 times smaller than those for children. Margins of safety (MOSs) for an adult’s exposure to total prescribed estrogens in drinking water vary from about 135 to > 17,000, depending on ADI. MOSs for exposure to total estrogens in drinking water are about 2 times lower than MOSs for prescribed estrogens. Depending on the ADI that is used, MOSs for young children range from 28 to 5,120 for total estrogens (including both prescribed and naturally occurring sources) in drinking water. Conclusions The consistently large MOEs and MOSs strongly suggest that prescribed and total estrogens that may potentially be present in drinking water in the United States are not causing adverse effects in U.S. residents, including sensitive subpopulations. |
nfcorpus-qrel-MED-1598 | Generate text that best answers this question: carcinogens | Cigarette Smoke Toxins Deposited on Surfaces: Implications for Human Health
Cigarette smoking remains a significant health threat for smokers and nonsmokers alike. Secondhand smoke (SHS) is intrinsically more toxic than directly inhaled smoke. Recently, a new threat has been discovered – Thirdhand smoke (THS) – the accumulation of SHS on surfaces that ages with time, becoming progressively more toxic. THS is a potential health threat to children, spouses of smokers and workers in environments where smoking is or has been allowed. The goal of this study is to investigate the effects of THS on liver, lung, skin healing, and behavior, using an animal model exposed to THS under conditions that mimic exposure of humans. THS-exposed mice show alterations in multiple organ systems and excrete levels of NNAL (a tobacco-specific carcinogen biomarker) similar to those found in children exposed to SHS (and consequently to THS). In liver, THS leads to increased lipid levels and non-alcoholic fatty liver disease, a precursor to cirrhosis and cancer and a potential contributor to cardiovascular disease. In lung, THS stimulates excess collagen production and high levels of inflammatory cytokines, suggesting propensity for fibrosis with implications for inflammation-induced diseases such as chronic obstructive pulmonary disease and asthma. In wounded skin, healing in THS-exposed mice has many characteristics of the poor healing of surgical incisions observed in human smokers. Lastly, behavioral tests show that THS-exposed mice become hyperactive. The latter data, combined with emerging associated behavioral problems in children exposed to SHS/THS, suggest that, with prolonged exposure, they may be at significant risk for developing more severe neurological disorders. These results provide a basis for studies on the toxic effects of THS in humans and inform potential regulatory policies to prevent involuntary exposure to THS. |
nfcorpus-qrel-MED-1599 | Generate text that best answers this question: carcinogens | Exposure to nitrosamines in thirdhand tobacco smoke increases cancer risk in non-smokers.
In addition to passive inhalation, non-smokers, and especially children, are exposed to residual tobacco smoke gases and particles that are deposited to surfaces and dust, known as thirdhand smoke (THS). However, until now the potential cancer risks of this pathway of exposure have been highly uncertain and not considered in public health policy. In this study, we estimate for the first time the potential cancer risk by age group through non-dietary ingestion and dermal exposure to carcinogen N-nitrosamines and tobacco-specific nitrosamines (TSNAs) measured in house dust samples. Using a highly sensitive and selective analytical approach we have determined the presence of nicotine, eight N-nitrosamines and five tobacco-specific nitrosamines in forty-six settled dust samples from homes occupied by both smokers and non-smokers. Using observations of house dust composition, we have estimated the cancer risk by applying the most recent official toxicological information. Calculated cancer risks through exposure to the observed levels of TSNAs at an early life stage (1 to 6years old) exceeded the upper-bound risk recommended by the USEPA in 77% of smokers' and 64% of non-smokers' homes. The maximum risk from exposure to all nitrosamines measured in a smoker occupied home was one excess cancer case per one thousand population exposed. The results presented here highlight the potentially severe long-term consequences of THS exposure, particularly to children, and give strong evidence of its potential health risk and, therefore, they should be considered when developing future environmental and health policies. Copyright © 2014 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1600 | Generate text that best answers this question: carcinogens | Beyond celery and starter culture: advances in natural/organic curing processes in the United States.
Over the past 10years there has been ongoing development of curing processes with natural ingredients designed to meet consumer demand and regulatory requirements for natural and organic processed meats. Initially, these processes utilized celery concentrates with a high nitrate content combined with a nitrate-reducing starter culture. Subsequent advances included celery concentrates with the nitrate converted to nitrite by suppliers. Further, as questions developed concerning reduced concentration of preservatives and the microbiological safety of these processed meats, additional advances have resulted in a wide variety of ingredients and processes designed to provide supplementary antimicrobial effects for improved product safety. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1601 | Generate text that best answers this question: carcinogens | Survey of naturally and conventionally cured commercial frankfurters, ham, and bacon for physio-chemical characteristics that affect bacterial growth.
Natural and organic food regulations preclude the use of sodium nitrite/nitrate and other antimicrobials for processed meat products. Consequently, processors have begun to use natural nitrate/nitrite sources, such as celery juice/powder, sea salt, and turbinado sugar, to manufacture natural and organic products with cured meat characteristics but without sodium nitrite. The objective of this study was to compare physio-chemical characteristics that affect Clostridium perfringens and Listeria monocytogenes growth in naturally cured and traditionally cured commercial frankfurters, hams, and bacon. Correlations of specific product characteristics to pathogen growth varied between products and pathogens, though water activity, salt concentration, and product composition (moisture, protein and fat) were common intrinsic factors correlated to pathogen growth across products. Other frequently correlated traits were related to curing reactions such as % cured pigment. Residual nitrite and nitrate were significantly correlated to C. perfringens growth but only for the ham products. Copyright © 2012 Elsevier Ltd. All rights reserved. |
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