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Results 401 - 450 of 587
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Kimura M - - 1990
To clarify the cooking losses of minerals (sodium, potassium, phosphorus, calcium, magnesium, iron, zinc, manganese, copper), various food materials were analyzed before and after cooking, and the following results were obtained. (1) The mineral contents of cooked foods in mass cooking were on an average about 60-70 percent of those ...
Tutelyan V A - - 1990
The content of volatile N-nitrosamines in over 4000 samples of domestic foodstuffs of plant and animal origin were studied. It was found that 88% of the samples studied contained N-nitrosamines, the greatest amounts being detected in some samples of malt and beer, fish products and some meat products. The impact ...
Wettig K - - 1990
Mean nitrate content in the morning urine of 117 patients with giardiasis comprises 155.3 mg/l, which exceeds about 4 fold the normal value. Maximum concentrations of 1000 mg/l were observed. Under treatment with metronidazol (Vagimid) nitrate content at first increased and then restored to normal. Endogenously synthesized nitrate with giardiasis ...
Poirier S - - 1989
Traditional life-style, especially food habits, infection by Epstein-Barr virus (EBV) and genetic factors, have been associated with an increased risk of nasopharyngeal carcinoma (NPC). N-Nitroso compounds and other carcinogens either present in food or formed endogenously, as well as food constituents that activate EBV, have been suspected as etiological factors ...
Perciballi M - - 1989
The endogenous formation of N-nitrosodimethylamine (NDMA) was investigated in the ferret by inhibiting metabolism and monitoring urinary NDMA levels. The addition of 1.0 mg/ml of 4-methylpyrazole (4-MP) to the drinking water was sufficient to allow a 13% urinary recovery of a 4.0 nmol oral dose of NDMA to be made ...
Davis D L - - 1989
Over the past two decades, marked shifts have occurred in cancer mortality in the United States, the United Kingdom, and the Federal Republic of Germany. Stomach cancer mortality has declined sharply, while brain cancer and multiple myeloma increased nearly twofold for persons ages 75 to 84. Total cancer incidence in ...
Esumi H - - 1989
The mutagenic compound, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), originally isolated from cooked beef, was tested for carcinogenicity in CDF1 mice of both sexes. When PhIP was given in the diet at a concentration of 0.04%, high incidences and early appearances of lymphomas were observed in both sexes during the 579-day experiment.
Tucker J D - - 1989
Mutagenic 1,2-dicarbonyls have been reported to occur in coffee and other beverages and in various foods. We have measured the induction of sister-chromatid exchanges (SCEs) and endoreduplicated cells (ERCs) to determine the genotoxicity of various 1,2-dicarbonyl compounds in Chinese hamster ovary (CHO) AUXB1 cells and human peripheral lymphocytes. The 1,2-dicarbonyls ...
Doolittle D J - - 1989
The effects of cooking methods on the in vitro mutagenicity of individual foods, the in vitro mutagenicity of meals containing those foods, and the mutagenic exposure of human volunteers following consumption of the meals were examined using Ames bacterial strain TA98 with S-9 metabolic activation. Three methods of food preparation--boiling, ...
Mallett A K - - 1989
Male Sprague-Dawley rats were fed a purified diet or one supplemented with the glycosidic plant flavonoid (+)rutin for 14 days. Rutin treatment significantly increased caecal bacterial beta-glucosidase activity (responsible for the conversion of rutin to the flavonoid quercetin) and there was an associated increase in the capacity of hepatic fractions ...
Miller B J - - 1989
Differences in volatile N-nitrosamines (NNAs) found in nitrite-cured bacon cooked in an electric skillet and a microwave oven were determined. Samples of bacon were fried in an electric skillet at 171 and 206 degrees C and in a standard microwave oven (rated at 700 W full power) for 45 and ...
Radcliffe B C - - 1989
1. Nitrite and nitrate levels were measured in samples from ileostomy bags or stomal samples of thirty-one ileostomists (twenty-two ulcerative colitis, nine Crohn's disease), 14-16 h after ingestion of a conventional meal or a meal containing a high content of nitrite and nitrate. 2. Ileostomy samples were decolourized with barium ...
Grolier P - - 1989
The effects of vitamin A dietary intake (2 and 20 IU */g of food) on the mutagenic activity of benzo[a]pyrene (B(a)P) toward Salmonella typhimurium (TA98) were studied either in control rats or in animals treated by the PCB congeners 2,4,5,2',4',5'-hexachlorobiphenyl [2,4,5)2Cl) and 3,4,3',4'-tetrachlorobiphenyl [3,4)2Cl). (3,4)2Cl (a planar compound) strongly increased ...
Ohshima H - - 1989
Epidemiological studies have associated the consumption of smoked fish and meat products with an increased risk of stomach cancer. Therefore, the reaction of such smoked foods with nitrite under acidic conditions was investigated and was shown to produce potent direct-acting genotoxic substances as detected by the SOS Chromotest. Similar genotoxic ...
Snyderwine E G - - 1989
Heterocyclic arylamines found in cooked foods including fish and beef are potent mutagens and carcinogens. The purpose of this investigation was to determine the specificity of cytochromes P1-450 and P3-450 toward the metabolic activation of these arylamines. We used a novel mutagenicity test system which combined human cells expressing either ...
Hotchkiss J H - - 1989
Most western-style foods have been analysed for the presence of volatile N-nitrosamines. Relatively few foods consistently contain detectable (greater than 0.1 microgram/kg) amounts of volatile N-nitrosamines. The major known contributors to dietary volatile N-nitrosamines are nitrite-cured meats, particularly fried bacon, and beer. The amount of volatile N-nitrosamines in these foods ...
Fiddler W - - 1989
Dry-cured or "country-style" bacon is a low volume specialty product typically made by small producers whose production practices vary widely. These practices include the direct application of dry-cure formulations containing varying concentrations of salt, sugar, flavoring agents, sodium nitrite, and sometimes sodium nitrate, and the use of lengthy curing and ...
BaraƄski B - - 1989
The study was aimed at the estimation of occupational exposure to mutagenic substances in a piston-ring foundry. The following samples were examined: solid phase of aerosol from the foundry and from different places of urban environment together with the foundry workers' urine collected during the 8-hour shift. The mutagenic substances ...
Kurelec B - - 1989
1. The in vitro incubation of mussel digestive gland with 1 mM aminofluorene resulted in the formation of glucuronides that (a) became mutagenic with carp liver S9, and (b) liberated S9-dependent mutagenic aglucones after beta-glucuronidase treatment. 2. Natural populations of mussels from unpolluted and polluted sites, as well as mussels ...
Coogan T P - - 1989
The toxicity and carcinogenicity of nickel compounds are considered in three broad categories: (1) systemic toxicology, (2) molecular toxicology, and (3) carcinogenicity. The systemic toxicity of nickel compounds is examined based upon human and animal studies. The major organs affected are discussed in three categories: (1) kidney, (2) immune system, ...
Lyon J L - - 1988
High-temperature cooking of foods produces a variety of mutagenic substances. Because of the association of such substances with carcinogenesis, the authors used a case-control study of colon cancer conducted in Utah between 1977 and 1979 with 246 cases and 484 controls to test the hypothesis that persons with colon cancer ...
Carman R J - - 1988
The dietary carcinogen, 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ) is mutagenic in the Salmonella/microsomal mutagenicity assay when activated by microsomal enzymes. IQ is found in many cooked foods, notably fried beef and pork. In laboratory rodents IQ is carcinogenic. We showed that mixed and pure cultures of human intestinal anaerobes, notably Eubacterium spp., metabolized ...
Yano M - - 1988
Broiled chicken, pork, mutton, beef and sun-dried sardine were found to yield direct-acting mutagenicity after nitrite treatment. When 50% methanol extracts of cooked foods were treated with 50 mM nitrite at pH 3 for 1 h at 37 degrees C, they induced 3800-17,900 revertants of Salmonella typhimurium TA100 and 15,000-43,600 ...
Perera F - - 1988
In 1987, investigators (Ames et al.) concluded that the risks of man-made industrial carcinogens and pesticides (outside of the workplace) are trivial compared with the risks of naturally occurring carcinogens found mostly in the diet. They used a ranking system based on human exposure and rodent potency (HERP) data to ...
Kronberg L - - 1988
The Ames mutagenicity and the concentration of the strong Ames mutagen 3-chloro-4-(dichloro-methyl)-5-hydroxy-2(5H)-furanone (MX) and its geometric isomer E-2-chloro-3-(dichloromethyl)-4-oxobutenoic acid (E-MX), derived from chlorination of humus, were determined in XAD extracts of tap water collected from 26 localities in Finland. The 23 tap waters treated with disinfectants gave a positive response ...
Osterdahl B G - - 1988
Foods on the Swedish market in 1980-1986 were analysed for volatile N-nitrosamines using gas chromatography-thermal energy analysis. Detectable levels were found in 474 of the 764 samples analysed. The average daily intake of volatile N-nitrosamines was estimated to be 0.29 microgram per person. Over 93% of the intake comes from ...
Zhang X M - - 1988
Samples of 7 foods commonly eaten in the Northeast of China (i.e. fried and broiled fishes and broiled meat) were tested for mutagenicity on Salmonella typhimurium TA98 with S9 mix. The basic fractions of the samples were mutagenic, inducing 33-2930 revertants/g of cooked food. Fried walleye pollack (a kind of ...
Ichinose H - - 1988
We investigated the effects of 14 heterocyclic amines in food on nigro-striatal dopaminergic neurons. Among 14 compounds tested, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) caused substantial decreases in 3,4-dihydroxy-phenylalanine (DOPA) formation in striatal tissue slice system. When Trp-P-1 or Trp-P-2 was unilaterally infused in the rat striatum by an in vivo ...
Tsuda M - - 1988
When five volunteers were given food containing cod and vegetables (a traditional Japanese food, called tara-chiri), their urinary excretion of N-nitrosothioproline increased from 7.9 +/- 4.2 (SD) micrograms/day to 110 +/- 64.5 micrograms/day. This increase was accounted for by in vivo nitrosation of of thioproline by nitrite formed from nitrate ...
Yamamoto M - - 1988
The effects of food components and food additives on the formation of nitrosamides were studied. Citrate accelerated nitrosamide formation from nitrite and various precursors, such as ureas, urethanes, guanidines and amides. The accelerating effects of citrate on the formation of methylurea and ethylenethiourea were larger at higher pH values. The ...
Piche L A - - 1988
The form(s) in which malondialdehyde (MDA), a mutagenic product of the oxidative decomposition of polyunsaturated fatty acids (PUFA), occurs in foods was investigated. Several foods of animal origin (ground beef, smoked fish, chicken, sausages) were digested in vitro using pepsin and porcine intestinal fluid and the occurrence of MDA derivatives ...
Groenen P J - - 1988
N-Nitroso compounds may well rank high among the genotoxic carcinogens present in our environment. Small amounts of such compounds may be formed in the human stomach after consumption of high-nitrate vegetables. Volatile nitrosamines can be conveniently determined but reliable methods of analysis for non-volatile N-nitroso compounds are still lacking. In ...
Siddiqi M - - 1988
Several commonly used raw foodstuffs from a high risk esophageal cancer region in Kashmir (India) were analysed for the presence of N-nitroso compounds. The food items were selected on the basis of their frequent consumption with particular emphasis on the preserved foods (dried, pickled and smoked) and those which are ...
Bressani R - - 1988
Bean cooking broth or liquor is a food preparation that results from cooking beans under a number of circumstances. This preparation is the first bean-derived food provided by mothers to their children as young as two months of age. Because of this, bean cooking plays an important nutritional role that ...
Negishi T - - 1988
The nucleoside analogue N4-aminocytidine is known to induce mutations in bacteria, and was shown to induce somatic mutations in Drosophila melanogaster after larval administration. The assay system employed was a wing-hair mutation spot test developed by Würgler and co-workers. The potency of N4-aminocytidine to induce somatic mutation is comparable to ...
Schaeffer D J - - 1987
Many toxicological problems involve interdependence among several endpoints, the values of which vary randomly over time and in relation to each other. For two endpoints, correlation analysis can be used to determine interdependence. Since correlation between more than two endpoints is not defined, higher order interdependence is determined using multivariate ...
Hoffmann D - - 1987
The oral use of snuff is causatively associated with cancer of the oral cavity. Since most epidemiologic studies to date relate to the long-term use of dry snuff, which has dominated the U.S. smokeless tobacco market in the past, the concentrations of several toxic and carcinogenic agents in the three ...
Laser Reuterswärd A - - 1987
Thirteen commercial meat-flavour samples were analysed for creatine and creatinine content and tested for mutagenicity in the Ames Salmonella/microsome test. In most samples, more than 50% of the creatine had been converted to creatinine. Mutagenicity was related to the creatinine content: 150 mumol creatinine/g dry matter (gdm) gave upwards of ...
Hemavathy K C - - 1987
Lannate 20 a carbamate pesticide was evaluated for its mutagenicity in Drosophila melanogaster by the sex-linked recessive lethals and chromosome II-III translocation tests by continuous larval feeding. The 3 sublethal doses of 0.2, 0.4 and 0.6 microliter of Lannate per 100 ml of the food medium induced a significant (P ...
Knight T M - - 1987
A survey was conducted of the dietary intake of nitrate and nitrite of 747 people aged 15-74 yr living in four regions in Britain. The mean intakes from food were estimated to be about 95 mg nitrate and 1.4 mg nitrite. Vegetables contributed over 90% of the nitrate intake and ...
Poirier S - - 1987
On the basis of anthropological pilot studies on diet in Tunisia, south China and Greenland, food items consumed frequently by these populations at high risk for NPC were analysed for volatile nitrosamines using gas chromatography combined with a thermal energy analyzer. Relatively high levels of N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR) and ...
Rosenkranz H S - - 1987
N-Nitrosothiazolidine 4-carboxylic acid (NTCA), a sulphur-containing nitrosamine present in human urine, was predicted to be non-carcinogenic by CASE, the newly developed Computer Automated Structure Evaluating system. On the other hand, N-nitrosothiazolidine (NTHZ), a nitrosamine present in food products, was predicted to be carcinogenic. The putative non-carcinogenic NTCA may be metabolized ...
Ohyama S - - 1987
Mutagenicity in the urine of four non-smoking individuals who had eaten salted salmon cooked at home for both lunch and supper was monitored by means of Salmonella/microsome mutagenicity tests. Extracts from fresh and salted salmon had the same level of mutagenicity after being cooked for 10 min at 200 degrees ...
Bryant M S - - 1987
A quantitative method has been developed for the analysis of 4-aminobiphenyl (4-ABP) covalently bound as the sulfinic acid amide to the 93 beta cysteine of human hemoglobin. The method uses mild basic hydrolysis of hemoglobin to release the parent amine, derivatization to form the pentafluoropropionamide, and capillary gas chromatography with ...
Poirier S - - 1987
Fifty-four samples of foods consumed frequently in Tunisia, southern China and Greenland, all high-risk areas for nasopharyngeal carcinoma (NPC), were analysed for the presence of volatile nitrosamines by gas chromatography (GC) combined with a thermal energy analyser (TEA). Relatively high levels of N-nitrosodimethylamine (NDMA), N-nitrosopiperidine (NPIP) and N-nitrosopyrrolidine (NPYR) were ...
Massey R C - - 1987
The classes of cooked foods that contain detectable levels of mutagenic activity are discussed together with the effects of different cooking procedures on the extent of mutagen formation. Analytical procedures that have so far been devised to quantify the concentrations of specific mutagenic compounds are described and the levels of ...
Wallace W E - - 1987
Diesel exhaust particulate material from exhaust pipe scrapings of two trucks, diluted automobile diesel exhaust particulate material collected on filters, and two oil shale ores were prepared for the Ames mutagenicity assay by dichloromethane (DCM) extraction, by dispersion into 0.85% saline, or by dispersion into dipalmitoyl lecithin (DPL) emulsion in ...
Hartman Z - - 1987
Ergothioneine, a novel imidazole sulfhydryl/thione compound formed in millimolar amounts by fungi, is a potentially important defense against electrophiles and free radicals. Protection may well occur both in organisms that synthesize ergothioneine and in animals including man that ingest and store ergothioneine in red blood cells, the liver, seminal fluid, ...
Miller E C - - 1986
The principal carcinogens and mutagens that have been identified in human foods are reviewed. These agents may occur in foods as naturally occurring components (e.g., metabolites made by plant or fungal cells), components of contaminating plants or microorganisms, food additives (usually unintentional), or products that arise during processing or cooking. ...
Palmer S - - 1986
Very low levels of a large variety of non-nutritive chemicals occur in the diet. Among those that occur naturally are metabolites of molds (for example, mycotoxins) and bacteria (for example, nitrosamines) and natural constituents of plants (for example, pyrrolizidine alkaloids). Many of these are occasional contaminants, whereas others are normal ...
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