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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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, ...
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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 ...
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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 ...
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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 ...
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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 ...
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LutyĆski 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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Ologhobo A D - - 1996
Nitrate, nitrite and nitrosamines were analysed in poultry feeds, meat and eggs. The poultry meat was boiled and roasted while the eggs were raw and boiled, and the effects of these processing treatments on the level of these compounds were investigated. Nitrate levels in the meat samples were significantly (P ...
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Davies D S - - 1996
A significant proportion of the mutagenic material present in cooked beef is accounted for by 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) which are formed during the cooking of meat. N-hydroxylation catalyzed by CYP1A2 is the major pathway of metbolism of MeIQx and PhIP and is solely responsible for the generation of ...
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Sato M I - - 1995
The mutagenicity of airborne particulate matter at three different sites within the São Paulo urban area and the Cubatão industrial area, São Paulo State, Brazil, was evaluated using the Salmonella mutagenicity assay over a year's period (June 1990-May 1991). Total suspended particles (TSP) were collected using a Hi-vol sampler and ...
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Thompson L H - - 1995
We have developed metabolically competent Chinese hamster ovary (CHO) cells to evaluate the genotoxicity associated with heterocyclic amines, such as those that are present in cooked foods. Into repair-deficient UV5 cells we introduced cDNAs for expressing cytochrome P450IA2 and acetyltransferases. We then genetically reverted these transformed lines to obtain matched ...
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Kohlmeier L - - 1995
Dietary components express a wide range of activities that can affect carcinogenesis. Naturally occurring substances in foods have been shown in laboratory experiments to serve as dietary antimutagens, either as bioantimutagens or as desmutagens. Dietary desmutagens may function as chemical inactivaters, enzymatic inducers, scavengers, or antioxidants. Dietary components may also ...
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Thiébaud H P - - 1995
Airborne cooking by-products from frying beef (hamburgers), pork (bacon strips) and soybean-based food (tempeh burgers) were collected, extracted, tested for mutagenicity and chemically analysed. The fumes generated by frying pork and beef were mutagenic, with 4900 and 1300 revertants/g of food cooked, respectively. No mutagenicity was detected in fumes from ...
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Stavric B - - 1995
Food products derived from heat-treated (fried, broiled, baked) meat may contain traces of mutagenic heterocyclic amine contaminants, some of which are proven carcinogens in rodents. To confirm their presence and range in Canadian foods, and estimate the average human intake of these types of mutagens from frequently consumed heat-processed foods, ...
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Hignett M - - 1995
OBJECTIVES: To study perforation rates of sterile transvaginal ultrasound probe covers before and after oocyte retrieval (OPU) in an IVF-ET program. METHODS: Transvaginal ultrasound probe sheaths from two different manufacturers were studied, Cook Innoray (Cook-Canada #TTUPS-100) and Swemed Lab (Frolunda Sweden #715). After controlled ovarian stimulation, OPU was done using ...
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Lewis D F - - 1995
Quantitative structure-activity relationships between chemical structure and Ames mutagenicity for a group of 24 food mutagens, including 17 cooked-food heterocyclic amines, have been determined. For the TA98 strain of Salmonella typhimurium (frameshift mutagens) the best correlation of mutagenicity is with molecular diameter (R = 0.91), while for the TA100 strain ...
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Knize M G - - 1995
Heterocyclic aromatic amines are sometimes formed during the cooking of muscle meats, and their mutagenic and carcinogenic effects are of potential concern in the aetiology of human cancer. In a large survey of the heterocyclic amine content of foods, fried or charbroiled hamburgers, fried chicken, chicken breast sandwiches, fish sandwiches ...
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Duncan C - - 1995
High concentrations of nitrite present in saliva (derived from dietary nitrate) may, upon acidification, generate nitrogen oxides in the stomach in sufficient amounts to provide protection from swallowed pathogens. We now show that, in the rat, reduction of nitrate to nitrite is confined to a specialized area on the posterior ...
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Lemke L E - - 1995
1-Hydrazinophthalazine [hydralazine (HDZ)] is a hydrazine derivative that is a direct acting vasodilator effective in the treatment of essential hypertension. HDZ is biotransformed by the phase II conjugation enzyme N-acetyltransferase (NAT) forming acetyl HDZ, which spontaneously cyclized to the stable product 3-methyl-s-triazolo- [3,4-alpha]-phthalazine (MTP). Therapeutic use of HDZ has resulted ...
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Laquerbe A - - 1995
Using the 4,5',8-trimethylpsoralen in combination with the reirradiation protocol, we show that, in normal human lymphoblasts, the cytotoxic potential of photoinduced cross-links (CL) is higher than that of monoadducts (MA). In contrast to cytotoxicity, the significant increase in the proportion of CL, at a constant level of total adducts, had ...
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Strickland P T - - 1995
The major sources of human exposure to environmental carcinogens are through inhalation, ingestion, and percutaneous absorption. Food-borne carcinogens constitute the primary source of ingested carcinogens. Epidemiological analyses indicate that 20-50% of all human cancer is due to dietary causes, unfortunately, few specific etiologic agents have been identified. The use of ...
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Cabral L C - - 1995
Changes in cooking requirements and chemical composition of whole and dehulled soybeans, stored in 2 different environments [25 degrees C /75% R.H. (Environment 1) and 38 degrees C /90% R.H. (Environment 2)], were studied. Rate of water absorption and solid losses during cooking were higher for the dehulled soybeans at ...
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Pobel D - - 1995
A case-control study on gastric cancer and diet was conducted in Marseille (France). Ninety-two patients with histologically confirmed adenocarcinoma and 128 controls undergoing functional reeducation for injuries or trauma were interviewed by a trained dietician using a dietary history questionnaire on their usual diet during the year preceding the first ...
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Layton D W - - 1995
Heterocyclic amines (HAs) are formed as pyrolysis products during the cooking of meats/fish. These substances are potent mutagens in the Ames/Salmonella assay and are also carcinogens in laboratory animals. In order to assess the magnitude of the cancer risk posed by their presence in the US diet, we estimated the ...
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Knize M G - - 1995
The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonella test with ...
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Gross G A - - 1995
Heterocyclic aromatic amines (HAs) may be formed during heat-processing of proteinaceous foods. All HAs are mutagenic in the Ames test, and many are animal and non-human primate carcinogens. The information on human dietary exposure is, therefore, of primary importance to accurately assess this health risk. A sensitive multiresidue method for ...
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