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Results 251 - 300 of 590
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Malaveille C - - 1998
Human urine is known to contain substances that strongly inhibit bacterial mutagenicity of aromatic and heterocyclic amines in vitro. The biological relevance of these anti-mutagens was examined by comparing levels of tobacco-related DNA adducts in exfoliated urothelial cells from smokers with the anti-mutagenic activity in corresponding 24-h urine samples. An ...
Anderson D - - 1998
The flavonoids, silymarin, myricetin, quercitin, kaempferol, rutin and kaempferol-3-rutinoside have been examined in combination with the food mutagens, 3-amino-1-methyl-5H-pyrido (4,3-b)indole (Trp-P-2) and 2-amino-3-methylimidazo-(4,5-f) quinoline (IQ), in the Comet assay in human lymphocytes from donor A and human sperm from donor B. These compounds alone have been shown to produce positive ...
Byrne C - - 1998
Cooking meat creates heterocyclic amines (HCAs) through pyrolysis of amino acids and creatinine. Although recognized as mutagenic, the etiological role of HCA in human cancer is unclear, due to the lack of information on the effect of typical food cooking methods on HCA concentrations and on variation in HCA exposure ...
Arimoto-Kobayashi S - - 1998
Early work from our laboratory has shown that the mutagenicity of heterocyclic amines in Salmonella can be inhibited by hemin and chlorophyllins. We have speculated that the inhibition is a result of complex formation between heterocyclic amines and the pigments, and the speculation has been given a line of experimental ...
Mauthe R J - - 1998
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mammary carcinogen in female rats and is present in a wide variety of cooked meats. We address here the excretion of PhIP and its metabolites into the breast-milk of lactating rats and the ability of chlorophyllin, a food product derivative with chemopreventive properties, to affect these ...
Siu D C - - 1998
Nitrate and nitrite are usually added to processed meat products to provide protection against microorganisms that cause food poisoning. Nitrite may react with secondary amines to form nitrosoamines, a class of carcinogens. Nitrate, although it is more stable than nitrite, can act as a reservoir for nitrite. Thus, both nitrate ...
Sinha R - - 1998
Meats cooked at high temperatures sometimes contain heterocyclic amines (HCAs) that are known mutagens and animal carcinogens, but their carcinogenic potential in humans has not been established. To investigate the association between HCAs and cancer, sources of exposure to these compounds need to be determined. Beef is the most frequently ...
Sinha R - - 1998
Heterocyclic amines (HCAs) are known mutagens and animal carcinogens produced in meats cooked at high temperature. As pork is the second most frequently consumed meat in the United States, five predominant HCAs [2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4.5-f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)] were measured in various pork products, cooked ...
Battershill J M - - 1998
1. The International Conference on the Harmonisation of Technical Requirements for the Registration of Pharmaceuticals for human use (ICH) has agreed that bioassay data from only one species, the rat, supported by appropriate mutagenicity and pharmacokinetic data and also information from new (unvalidated) short term in vivo screening tests for ...
Dashwood R - - 1998
The anticarcinogenic activity of chlorophyllin (CHL), a water-soluble derivative of chlorophyll, was first reported in rainbow trout. This review describes certain experiments which set the stage for long-term tumor bioassays, in trout and other species, using CHL and various food-borne carcinogens. Initial work with trout and rat liver enzymes in ...
Schrader T J - - 1998
The polychlorinated pesticide toxaphene has been identified as a persistent environmental contaminant and is of particular concern in the Great Lakes and Arctic regions of Canada. Inconsistencies in published in vitro genotoxicology studies have hindered risk assessments of toxaphene exposure. When toxaphene mutagenicity was re-evaluated in the Ames Salmonella/microsome assay ...
McKee S R - - 1998
Rapid post-mortem metabolism concomitant with the early onset of rigor mortis can lead to the development of pale, soft, and exudative (PSE) meat. However, a reliable, nonlethal method for induction of this syndrome for the ante-mortem identification of abnormal turkeys has not been identified. The present study was conducted to ...
van Maanen J M - - 1998
We studied the formation of carcinogenic nitrosamines during consumption of food rich in nitrate and amines, and its possible inhibition by use of an antibacterial mouthwash. Twelve volunteers were fed a diet containing the high-nitrate vegetables lettuce or spinach during two periods of four consecutive days, in combination with fish ...
Duncan C - - 1997
Over the last 20 years, dietary nitrate has been implicated in the formation of methemoglobin and carcinogenic nitrosamines in humans. This has led to restrictions of nitrate and nitrite levels in food and drinking water. However, there is no epidemiological evidence for an increased risk of gastric and intestinal cancer ...
Augustsson K - - 1997
Heterocyclic amines are possible human carcinogens and fried meat is an important source of exposure in the Western diet. To study the effect of heterocyclic amines in humans, accurate assessment of individual food consumption is essential. Parameters influencing the intake include the amount and type of meat ingested, frequency of ...
Atanasova-Goranova V K - - 1997
An experiment was conducted to study the efficacy of two tomato pastes and aronia nectar (fruit juice + pulp from the black chokeberry, Aronia melanocarpa Elliot) as inhibitors of nitrosamine production in cancer prophylaxis programmes. White male rats of the Wistar strain were employed in an acute trial. Aminopyrin+sodium nitrite ...
Skog K - - 1997
Fourteen cooked dishes with their corresponding pan residues were analysed for polar and non-polar heterocyclic amines using HPLC. The choice of foods, including beef, pork, poultry, game, fish, egg and sausages, was based on an investigation of an elderly population in Stockholm participating in an analytical epidemiological case-control study on ...
Hwang D F - - 1997
A rapid, sensitive and reproducible high-performance liquid chromatographic procedure for the determination of nine biogenic amines in fish by improved benzoylation with benzoyl chloride was developed. The benzoylation of amines with benzoyl chloride at 30 degrees C for 40 min was the optimal condition to eliminate the influence of interfering ...
Knize M G - - 1997
A number of related heterocyclic amines that are mutagenic in bacterial test systems and carcinogenic in animals are formed during the cooking of food. The most commonly reported and abundant compounds are PhIP, MeIQx, DiMeIQx, IQ and A alpha C. Using analysis by solid-phase extraction and HPLC, amounts found in ...
Wakabayashi K - - 1997
Various kinds of mutagenic and carcinogenic heterocyclic amines (HCAs) are produced by heating protein-rich foods, such as meat and fish. To evaluate the risk of these HCAs in terms of human cancer development, exposure levels must be measured. We therefore analyzed their amounts in various kinds of cooked foods and ...
Negishi T - - 1997
Chlorophyllin, a man-made water-soluble form of chlorophyll, is a focus of intensive studies from many laboratories for its antimutagenic and anticarcinogenic properties. Natural chlorophylls, in contrast, have been little studied in this regard. Since yellow-green vegetables are implicated to be protective against human cancers by epidemiological studies, it is important ...
González de Mejía E - - 1997
The principal natural food colorants used in modern food manufacture are anthocyanins, betalains, carotenoids, chlorophylls, riboflavin and caramel. Carotenoids (carotenes and xanthophylls) occur naturally in some foods such as carrots, red tomatoes, butter, cheese, paprika, palm oil, corn kernels, marigold petals, annatto, and red salmon. Carotenoids (alpha- or beta-carotene and ...
Probst-Hensch N M - - 1997
The often observed association between red meat and colorectal cancer could be due in part to mutagens, such as heterocyclic amines (HCA), that are present in cooked meat. HCAs are highly mutagenic and cause intestinal tumors in animals. The hypothesis that HCAs are also carcinogenic to humans remains to be ...
McNally N - - 1997
The authors describe a microplate-based high-throughput procedure for rapid assay of the enzyme activities of nitrate reductase and nitrite reductase, using extremely small volumes of reagents. The new procedure offers the advantages of rapidity, small sample size-nanoliter volumes, low cost, and a dramatic increase in the throughput sample number that ...
Anderson D - - 1997
The flavonoids silymarin, myricetin, quercetin, kaempferol, rutin, and kaempferol-3-rutinoside have been examined in combination with the food mutagens 3-amino-1-methyl-5H-pyrido (4,3-b)indole (Trp) and 2-amino-3-methylimidazo-4,5-f)quinoline (IQ) in the Comet assay in human lymphocytes from donors A and B and human sperm from donor B. These compounds alone have been shown to produce ...
Sasaki Y F - - 1996
The effect of Tochu tea, which is an aqueous extract of Eucommia ulmoides leaves and a popular-beverage in Japan, on the urine mutagenicity before and after ingestion of raw fish and cooked beef was studied using Salmonella typhimurium YG1024. Urines were collected from seven healthy, non-smoking Japanese women before and ...
Izquierdo-Pulido M - - 1996
Ten biogenic amines in Spanish beers were studied using HPLC, Agmatine, tyramine and putrescine were the prevailing amines, while histamine, beta-phenylethylamine, tryptamine, cadaverine, spermine and spermidine were detected at relatively low levels (in general < 2 mg/l). On the basis of the wide range of levels observed for tyramine (from ...
Weisburger J H - - 1996
Previous research suggested that the mutagenicity of some genotoxic carcinogens, mainly heterocyclic amines, was decreased by green or black tea extracts, or tea polyphenol fractions. Thus, it seemed important to test a variety of genotoxic carcinogens with distinct chemical structures and means of biochemical activation as regards modification of mutagenicity ...
Egberts J - - 1996
Changes in nitric oxide production result in changes in nitrate excretion, but these are difficult to detect if the daily intake of nitrate varies substantially. Instead of using a sample of the combined urine produced in 24 h for analysis, we studied the urine nitrate concentration in urine discharge at ...
Fielder R J - - 1996
The UK Committee on Carcinogenicity of Chemicals in Food, Consumer Products and the Environment (COC) and the related Committee on Mutagenicity provided advice on 1,3-butadiene in 1992. This followed detailed consideration of the available mutagenicity, animal carcinogenicity and epidemiology data plus information on toxicokinetics. They concluded that 1,3-butadiene was an ...
McDonald A L - - 1996
A pragmatic possible approach to the prioritization of chemical carcinogens occurring as food contaminants is described, based on the carcinogenic risk to the population. This should be of value in ensuring that resources for assessment and management of carcinogens in food are directed to the most important areas with regard ...
De Stefani E - - 1996
Evidence from animal studies indicates that various N-nitroso compounds are carcinogenic. We investigated whether consumption of nitrosodimethylamine (NDMA) and foods and beverages containing NDMA are carcinogenic for the lung. In a hospital-based case-control study in Uruguay, dietary intake of NDMA and its food sources was measured in 320 cases of ...
Tikkanen L M - - 1996
The effect of processing conditions on the mutagenic activity and sensory quality of everyday food was studied by investigating grilled chicken samples seasoned with four different marinades and grilled at temperatures of about 110, 170 and 220 degrees C. The amounts of the heterocyclic amines 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5,-b]pyridine were ...
Dich J - - 1996
Concern about potential health hazards of nitrate, nitrite and N-nitroso compounds necessitates calculations of exposures to these compounds and their distribution in normal populations. This study describes dietary intake of nitrate (NO3-), nitrite (NO2-) and N-nitrosodimethylamine (NDMA) among 5304 adult men and 4750 women, who participated in the Finnish Mobile ...
Kodell R L - - 1996
It has been established in the literature that constraints on the designs of experiments used to estimate carcinogenic potencies cause overestimation of true biological interspecies correlations of such potencies. This article explores the potential for appreciable underestimation of interspecies correlations, due to the experimental error that occurs in the estimation ...
Stavric B - - 1996
Water extracts of eight brands (five types: 'green', 'black', 'oolong', decaffeinated and instant) of common teas (derived from Camellia sinensis) and infusions of six randomly selected herbal teas were examined for inhibitory or potentiating effects on the mutagenicity of eight heterocyclic aromatic amines (HAA) using the Ames Salmonella typhimurium TA98 ...
G??nd??z T - - 1996
Thirteen aliphatic and four aromatic amines, namely diethylamine, triethylamine, n-propylamine, di-n-propylamine, tri-n-butylamine, isopropylamine, di-isopropylamine, n-butylamine, di-n-butylamine, tri-n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, aniline, N,N-dimethylaniline, 2-nitroaniline and 4-nitroaniline were titrated thermometrically with nitrosyl perchlorate in acetonitrile solvent. All the aliphatic amines gave very well-shaped thermometric titration curves. The calculated recovery values of the ...
Sugimura T - - 1996
Cancer cells are produced by the accumulation of genetic alterations in somatic cells. Those genetic alterations are produced by xenobiotics, which enter the human body from the environment, and by autobiotics, which are produced in the human body. Food contains many different types of xenobiotic mutagens/carcinogens and tumor promoters. Food ...
Kanazawa K - - 1996
BACKGROUND: Cancer of the sigmoid colon is especially sensitive to environmental factors such as food. The authors have conducted a series of studies with food as the external environmental factor and intestinal microflora as the internal environment factor in relation to sigmoid colon carcinogenesis. METHODS: Thirteen males who had previously ...
Silla Santos M H - - 1996
Biogenic amines are important nitrogen compounds of biological importance in vegetable, microbial and animal cells. They can be detected in both raw and processed foods. In food microbiology they have sometimes been related to spoilage and fermentation processes. Some toxicological characteristics and outbreaks of food poisoning are associated with histamine ...
Lindsay D G - - 1996
Both exogenous and endogenous mutagens have the potential to contribute to events leading to carcinogenesis. While many dietary exogenous mutagens have been characterized, aflatoxins are the only exogenous mutagens in food which have been shown to directly increase the risk of liver cancer in humans. Little attention has been given ...
Wu J - - 1996
Orthogonal array design (OAD) has been applied to the optimization of the capillary zone electrophoretic (CZE) analysis of heterocyclic amines (HCAs), carcinogenic and mutagenic compounds that are found in cooked foods. The factors affecting separation efficiency, such as the pH of the buffer solution, organic modifier and buffer concentrations, the ...
Chan T Y - - 1996
Methemoglobinemia is a potentially fatal condition. Previous reports of toxic methemoglobinemia due to food-borne nitrates and nitrites are reviewed. Contamination of food during manufacture or degradation of nitrates in vegetables appear to be the most important factors. Some food items, such as refrigerated "dim-sum", stuffed pork and Chinese sausages, are ...
Niphadkar M P - - 1996
The mutagenic potential of aqueous extracts of masheri (ME), chewing tobacco alone (CTE) and a mixture of chewing tobacco plus lime (CTLE) was tested using the Ames assay. ME exhibited mutagenicity in Salmonella typhimurium TA98 upon metabolic activation with aroclor-1254-induced rat liver S9, while nitrosation rendered it mutagenic in TA100 ...
Robbana-Barnat S - - 1996
This article deals with the mutagenic heterocyclic amines, especially the aminoimidazoazaarenes family, isolated from cooked foods. The conditions which lead to their occurrence in foods are discussed. This formation primarily depends on the characteristics of the food, such as the type of the food and the presence of precursors, water, ...
Surh Y J - - 1996
Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) is a major pungent ingredient of the Capsicum fruits such as hot green and red peppers. Besides its use as a food additive in various spicy cuisines, capsaicin is currently utilized for therapeutic purposes to treat various peripheral painful conditions such as rheumatoid arthritis and diabetic neuropathy. Considering ...
Abdel-Kader Z M - - 1996
Oxidative rancidity in fresh, frozen and cooked chicken breast and leg meat was evaluated by measuring malondialdehyde (MDA) in fat from meat with an improved 2-thiobarbituric acid (TBA) assay with antioxidant protection, and by measuring the relative fluorescent products of organic and aqueous layers from FOLCH extracted meat. Fresh samples ...
Atawodi S E - - 1996
Popular vegetables, condiments and some Nigerian staple foods were evaluated for their relative methylating potential due to nitrosamide formation following nitrosation under standardized conditions. Methylating activity of nitrosated foodstuffs, expressed as N-nitroso-N-methylurea equivalents, was determined by gas chromatography-thermal energy analysis. In positive samples (detection limit 10 microgram/kg) methylating activity detected ...
Williams G M - - 1996
The document "Risk Assessment of Carcinogens in Food with Special Consideration of Non-Genotoxic Carcinogens" was produced by the International Federation of Societies of Toxicologic Pathologists on the occasion of its triannual meeting in Tours, France, April 23-26, 1995. Subsequently, it was endorsed by the North American Society of Toxicologic Pathologists ...
LutyƄski R - - 1996
In the study it was intended to evaluate the concentration of nitrates and nitrites in some food products and samples of potable water collected in Kraków region and compile these results with frequency of recognised toxic methemoglobinemia cases. In the years 1991-1993 91 food samples, 288 samples of tap water ...
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