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Results 651 - 700 of 715
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Hashimoto Y - - 1980
Two potent mutagens, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), isolated from a tryptophan pyrolysate, and 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), isolated from a glutamic acid pyrolysate, modified calf thymus DNA in the presence of rat liver microsomes. The major base modified by Trp-P-2 was identified wih 3-(3-guanyl)amino-1-methyl-5H-pyrido[4,3-b]indole. The major base modified by Glu-P-1 was identified with 2-(8-guanyl)amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole. ...
Nestmann E R - - 1980
A chemical reaction occurs when trichloroacetic acid (TCA) is dissolved in dimethyl sulphoxide (DMSO), with the production of a short-lived mutagenic derivative which was detected using the Salmonella/mammalian-microsome plate overlay assay. Other interactions between test chemicals and solvents are discussed. Choice of proper solvents in mutagenicity testing is emphasized.
De Flora S - - 1980
A mutagenic response was obtained in the Salmonella/microsome reversion test by preincubating sodium nitrite and cimetidine in human gastric juice from untreated individuals, or even by adding nitrite to gastric juice samples from patients receiving cimetidine. Both base-pair substitutions (strains TA1535 and TA100) and, though very weakly, also frameshift errors ...
Archer M C - - 1980
Nitrohexane has been identified as a major product formed following treatment of corn (Zea mays) with nitrous acid. Preliminary evidence suggests that another compound isolated from the nitrosated corn is an unsaturated nitrolic acid. As an aid to the analysis of N-nitro compounds, we have characterized the response of a ...
Hathway D E - - 1980
Data derived from studies with vinylidene chloride (1,1-dichloroethylene)and 1,1,2-trichloroethylene suggest that similar mutagenic and tumorogenic properties in mice may be attributable to rearrangement of the 2 haloalkene-derived haloepoxides, respectively, into chloroacetyl chloride and dichloroacetyl chloride. On the other hand, the relative harmlessness of 1,1,2-trichloroethylene in rats and man is due ...
Lijinsky W - - 1980
Eighteen compounds structurally related to the mutagenic carcinogen vinyl chloride have been tested for mutagenicity in five strains of Salmonella typhimurium. Acrolein, acrolein diethylacetal, acrylonitrile, allyl alcohol, allyl bromide, crotonaldehyde, crotyl alcohol, and vinyl bromide were mutagenic with one or more strains; acrolein bisulfite, acrolein oxime, acrylamide, acrylic acid, allylamine, ...
Edwards G - - 1979
An intrahepatic host-mediated mutagenicity assay capable of detecting low levels of N-nitrosomorpholine (NMOR) is described. The indicator organism was Salmonella typhimurium TA1530 which had been injected intravenously 10 min prior to the administration of the test compound. The bacteria were subsequently recovered from the liver and scored for revertants by ...
Robach M C - - 1979
The effects of the initial pH and a "short pump" on the outgrowth of Clostridium sporogenes PA 3679 spores in comminuted cured pork were studied. Fresh ground pork was cured with salt, sugar, phosphate, ascorbate, and varying amounts of sodium nitrite and sorbic acid. The product was comminuted and inoculated ...
Maickel R P - - 1979
Commercially available isobutyl nitrite (iBN), n-butyl nitrite (nBN), sec-butyl nitrite (sBN) and tert-butyl nitrite (tBN) were found to be 63%, 79%, 44% and 96% pure, respectively, by GLC analysis. Pure samples of each compound were synthesized by the action of nitrous acid on each of the corresponding butyl alcohols; GLC ...
Bruce W R - - 1979
A comparison of two rapid and inexpensive in vivo mammalian assays and the Ames Salmonella assay is presented for 61 agents; Acetylsalicylic acid; Acriflavine; Actinomycin D; 2(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2); Aflatoxin B1; 2-aminofluorene; Aminopterin; Aroclor 1254; Ascorbic acid; Azathioprine; Benzo(a)pyrene; 5-Bromo-2'-deoxyuridine; Busulphan, Butylated hydroxytoluene; Cadmium chloride; Caffeine; Calcium cyclamate; Chloral hydrate; Chloromycetin ...
Matsushima T - - 1979
The aglycone methylazoxymethanol of the naturally occurring carcinogenic glucoside, cycasin, has previously been shown to be mutagenic, but cycasin per se has not. In this work, cycasin was demonstrated to be mutagenic using a modification of the Ames Salmonella test in which it was preincubated with beta-glucosidase and the tester ...
Sugimura T - - 1979
The charred surface of fish and beef showed strong mutagenic activity in Salmonella typhimurium test strains when activated by S-9 mix of rat liver. The pyrolysis products of proteins and amino acids were also highly mutagenic. Among the pyrolysis products of amino acids, those of tryptophan, serine, and glutamic acid ...
Ray U R - - 1979
Mutagenic specificity in response to chemical mutagens has been observed with certain temperature-sensitive mutants of reovirus type 3. One mutant induced by nitrous acid reverted specifically with nitrous acid. Three nitrosoguanidine-induced mutants reverted after nitrous acid treatment. These findings thus suggest that analysis of chemical induction of reversion from the ...
Zetterberg G - - 1979
MCPA and salicylic acid, two compounds with similar structures and almost the same dissociation pattern, were tested for lethal and mutagenic effects on, and uptake by, cells of Saccharomyces cerevisiae strain rad18. The results obtained with the two compounds were similar, suggesting a common mechanism of action. It is proposed ...
Munkres K D - - 1979
Ferrous ions were highly lethal and mutagenic to germinated conidia of Neurospora crassa. At comparable survival, treatment with 0.2 mM ferrous ions was 14- and 50-fold more mutagenic than ultra-violet irradiation or X-rays, respectively, in the reversion of an inositol auxotroph. Ascorbic acid alone (2 mM) was not reproducibly lethal ...
Wyman J F - - 1979
A strain of Pseudomonas aeruginosa reduced 2,4,6-trinitrophenol (picric acid) to 2-amino-4,6-dinitrophenol (picramic acid) under anaerobic conditions. Mutagenic assays of picric acid and picramic acid were carried out with histidine-requiring strains of Salmonella typhimurium. Picric acid (10 micrograms per plate) demonstrated mutagenicity (both frame shift and base substitution-gype mutations) only after ...
Nestmann E R - - 1979
Ten resin acids which have been identified as constituents of pulp and paper mill effluents have been examined for potential mutagenicity in the Salmonella/mammalian-microsome assay. Only neoabietic acid has been found to be mutagenic. Neoabietic acid showed dose-related increases in mutagenicity in strains TA1535, TA100, TA1538, and TA98, but not ...
Wehner F C - - 1978
17 mycotoxins produced by various Aspergillus and Penicillium species were screened for their mutagenic activity to Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537, both with and without metabolic activation. Austdiol, austocystins A and D, kojic acid and viridicatumtoxin were found to be mutagenic after metabolic activation, while austdiol was ...
Ofstad E B - - 1978
The content of chlorinated fat-soluble aromatic hydrocarbons was determined in fish from an area polluted by industrial effluents. The fish species investigated were selected among those used for human consumption. For some samples, both the fillet and liver were investigated. For others the whole fish was used. The following compounds ...
Commoner B - - 1978
Mutagens, distinguishable from benzo[a]pyrene and from mutagenic amino acid and protein pyrolysis products, are formed when ground beef is cooked in a home hamburger cooking appliance or when beef stock is concentrated, by boiling, to a paste known commercially as beef extract. "Well-done" hamburgers contain about 0.14 part per million ...
Bababunmi E A - - 1978
The incidence of primary liver cancer in the countries of tropical Africa is the highest in the world. There is a growing belief that the relatively high prevalence of hepatocellular carcinoma in Nigeria may have a multiple chemical factor etiology in such forms as food contaminants, herbal teas, and environmental ...
Yoshida D - - 1978
Pyrolyzates of protein and related materials were treated with nitrite under acidic conditions, and the mutagenic activity toward Salmonella tester strains was determined. After treatment with nitrite in acidic solution, casein pyrolyzate, an extract of roasted chicken meat, tobacco-smoke condensate and some aromatic amines showed appreciable decreases in their mutagenic ...
Robach M C - - 1978
A method for evaluating inhibition of Clostridium botulinum, C. sporogenes, and C. perfringens in cured meat products was developed. This system can easily be used in the microbiology laboratory using aluminum ointment tubes as the product container. Swells caused by gas production by the organism are easily observed by using ...
Yankeelov J A JA - - 1978
A mercapto analogue of histidine (1), (RS)-2-mercapto-3-(5-imidazolyl)propionic acid (2), was prepared by treatment of (RS)-2-bromo-3-(5-imidazolyl)propionic acid with trithiocarbonate. Decomposition of the resulting intermediate with hydrochloric acid followed by Sephadex G-15 chromatography permitted isolation of 2 as a hydrobromide complex having unusual stability and properties as evidenced by IR and 1H ...
Davies P J - - 1978
Treatment of diploid yeast cultures with the amino acid analogue, para-fluorophenylalanine (PFPA), at concentrations which caused inhibition of growth, resulted in up to 5 fold increases in the frequency of mitotic gene conversion at two different heteroallelic loci. With haploid yeast cultures, growth in PFPA increased the rate of forward ...
Bardodĕj Z - - 1978
The main products of styrene biotransformation excreted in human urine are mandelic and phenylglyoxylic acids. Phenylethylene oxide seems to be the first metabolite; this compound has been reported to be mutagenic and carcinogenic. The polarographic determination of mandelic acid has been used for about 20 years in Czechoslovakia as an ...
Corbett M D - - 1978
The ability of the green alga Chlorella pyrenoidosa to convert nitrosobenzene (I), phenylhydroxylamine (VI), aniline, and nitrobenzene to hydroxamic acid metabolites was investigated. Only nitrosobenzene and phenylhydroxylamine were partially converted to N-phenylacetohydroxamic acid (Va) and N-phenylglycolhydroxamic acid (Vb), with the latter compound being the major product. The possible mechanisms for ...
Brown J P - - 1978
Thirty-seven azo, xanthene and triphenylmethane dyes including FD and C colors currently approved for use in the U.S.A. and a number of delisted food colors, were tested in the Salmonella/microsome system. In addition to direct plate tests with five tester strains (TA1535, TA100, TA1537, TA1538, TA98), the azo dyes were ...
Teranishi K - - 1978
Air-borne particulate matter was collected on a filter, then extracted with benzene. The benzene-soluble material was separated into 5 fractions, namely acidic, basic, alipathic, polyaromatic and oxygenated fractions. The mutagenic activities of these fractions were examined with a set of Salmonella typhimurium mutants. The 6 mutants were from the TA1535 ...
Röper H - - 1978
The hydrochlorides of tetracycline, minocycline, chlorotetracycline, anhydrochlorotetracycline, desmethylchlorotetracycline, oxytetracycline and doxycycline were reacted with sodium nitrite for two hours at 37 degrees C in aqueous buffer solutions at pH 2 and 4 under simulated stomach conditions. NDMA formation was detected from minocycline, doxycycline, oxytetracycline and anhydrochlorotetracycline by GLC and GLC-MS ...
Nagasawa H T - - 1977
The N-nitro derivatives of secondary alpha-amino acids, viz., 1-nitroproline (1a) (L and D), 1-nitro-DL-pipecolic acid (2a), and N-nitrosarcosine (3a), were prepared by the oxidation of the corresponding nitrosamino acids with peroxytrifluoroacetic acid. These nitramino acids (1a-3a) were not active against Escherichia coli, Candida albicans, Pseudomonas aeruginosa, or Mycobacterium smegmatis, and ...
Silverman S J - - 1977
Of 30 bile acids tested, none was mutagenic in the Salmonella-mammalian-microsome test with indicator strains G46, TA1530, TA1535, TA1536, TA1537, TA1538, TA98, or TA100. However, when lithocholic acid or one of its conjugates was tested with suboptimal amounts of 2-aminoanthracene and phenobarbital-stimulated rat liver homogenate, enhancement and co-mutagenesis were observed ...
Markhinin E K - - 1977
Organic matter has been found in the juvenile ash of seven volcanoes in Kamchatka, the Kurile Islands and Indonesia. Its amount in one eruption is of the order of 1 00 000 tons. This matter constitutes a multicomponent mixture (more than 150 components) of, mainly, high boiling (b.p. over 250 ...
Nagel D - - 1977
Gyromitrin, acetaldehyde N-methyl-N-formylhydrazone, is a toxin present in edible wild mushroom Gyromitra esculenta. At 37 degrees under different acidic conditions (pH 1 to 3), mimicking the milieu of human stomach, gyromitrin is converted to methylhydrazine, a known tumor inducer in mice and hamsters, through an intermediate, N-methyl-N-formylhydrazine. In addition, methylhydrazine ...
Wang C Y - - 1977
P-Butoxyphenylacethydroxamic acid, benzohydroxamic acid, salicylhydroxamic acid, 2-naphthohydroxamic acid, indole-2-carbohydroxamic acid and benzoylaminoacethydroxamic acid were synthesized, and their mutagenicity for Salmonella typhimurium strains TA98 and TA100 were determined. Except for p-butoxyphenylacethydroxamic acid, all the hydroxamic acids were mutagenic for both strains. The mutagenicity progressed in the following order: 2-naphthohydroxamic acid greater ...
Mizusaki S - - 1977
Mutagenic activities of cigarette smoke condensate were assayed in the presence of S-9 Mix using Salmonella typhimurium TA 98. The results were examined in relation to chemical data of tobacco leaves. Among the nitrogenous constituents examined, the contents of total nitrogen and protein nitrogen and the soluble nitrogenous fraction were ...
Matsumoto T - - 1977
Pyrolyzates of 25 amino acids and 5 indole derivatives were tested for mutagenicity in the histidine-requiring mutant Salmonella typhimurium TA 98. Significant mutagenic activity was detected with pyrolyzates of most of the amino acids. These pyrolyzates required a liver microsomal fraction, as representative of mammalian metabolism, to be detected as ...
Radomski J L - - 1977
The glucuronic acid conjugate of N-hydroxy-4-aminobiphenyl (NOH-4-ABP) has been isolated in relatively pure form from the urine of dogs given 4-aminobiphenyl, utilizing molecular size, ion exchange, adsorption, and partition chromatography. This conjugate is an active mutagen in Salmonella typhimurium strains TA1538 and TA98 but not in TA1535 or TA1537. NOH-4-ABP ...
Královocová E - - 1977
The production of epsilon-pyrromycinone glycosides in Streptomyces galilaeus increased 12-fold, with respect to the wild strain, as a result of a sequential procedure including both natural selection and treatment with mutagens (nitrous acid, UV light and gamma-irradiation). Nitrous acid exhibited the highest mutagenic effect, both in increasing the productivity and ...
Baden J M - - 1976
The mutagenicity of halothane was tested in an in-vitro microbial assay system employing two histidine-dependent mutants of Salmonella typhimurium, TA98 and TA100, Halothane in concentrations ranging from 0.1 to 30 per cent was incubated with bacteria in the presence or absence of a metabolic activation system prepared from either rat ...
Hossain M M - - 1976
The micronucleus test was used to study possible mutagenic effects of (1) Irradiated potatoes extracted (a) immediately and (b) after 24-h storage following irradiation; (2) Irradiated and unirradiated chlorogenic acid; and (3) Trenimon. It was observed that irradiated potatoes (groups 1 a, b) and chlorogenic acid (group 2) did not ...
Rannug U - - 1976
Previous investigations have shown that the carcinogen vinyl chloride causes base-pair substitution in the bacterium Salmonella typhimurium. The ability of four conceivable metabolites-chloroethylene oxide, chloroacetaldehyde, 2-chloroethanol and chloroacetic acid-to cause base-pair substitution directly in Salmonella typhimurium TA1535 has been compared. The main comparison was performed at initial concentrations from 0.1 ...
Strnadová K - - 1976
A simple and speedy procedure is described for the preparation and application of nitrous acid in mutagenic experiments. The conventional incubation mixture of sodium nitrite solution with acetate buffer is replaced by an aqueous solution of nitrous acid prepared by running a solution of sodium nitrite through a column of ...
Laloraya M M MM Faculty of Life Sciences, University of Indore, Vigyan Bhawan, Khandwa Road, Indore, - - 1976
Gibberellic acid inhibition of betacyanin biosynthesis has been studied in Amaranthus caudatus L. using the pigment precursors L-tyrosine and L-dihydroxyphenylalanine. Precursors fed to gibberellic acid (GA) treated seedlings completely recovered betacyanin synthesis while the GA induced growth enhancement remained unaltered. Inhibition of betacyanin biosynthesis by GA is related to depletion ...
Boyland E - - 1976
Thiocyanate or bromide increased the colour formed by nitrite reacting with sulfanilic acid and naphthylethylenediamine. If the colour reagents were added together with thiocyanate (final concentration, M/10), the colour intensity was doubled. If sulfanilic acid was added three minutes before addition of naphthylethylenediamine, the relationship between nitrite concentration and colour ...
Swenson D H - - 1975
Aflatoxin B1-2,3-dichloride (AFB1-Cl2) was synthesized as a model for the probable ultimate carcinogen, aflatoxin B1-2,3-oxide. As expected for aflatoxin B1-2,3-oxide, AFB1-Cl2 has an electrophilic carbon 2; it decomposed in water (half-life of 0.5 min in 10% dimethyl sulfoxide, pH 7.4) with the formation of 3-chloro-2,3-dihydro-2-hydroxyaflatoxin B1 and 2,3-dihydro-2,3-dihydroxyaflatoxin B1. AFB1-Cl2 ...
Doubleday O P - - 1975
The photoreversibility of UV-induced mutations to Trp+ in strain Escherichia coli WP2 uvrA trp (unable to excise pyrimidine dimers) was lost at different rates during incubation in different media. In Casamino acids medium after a short initial lag, photoreversibility was lost over about one generation time; in minimal medium with ...
Chandha M S - - 1975
The formation of HCN, ammonium cyanide, alkylnitriles, aminoacetonitrile and its C- and N-methyl homologs was demonstrated earlier in a simulated Jovian atmosphere. The polymeric material resulting in these experiments was shown to give glycine, alanine, sarcosine, aspacrtic acid and some imino dibasic acids on acid hydrolysis suggesting thereby the participation ...
Katz S - - 1975
Reported is a series of studies in which several breakfast cereals were tested for the following properties: sugar retained by, and plaque formed on, extracted teeth that chewed the cereals: ability of the cereals to induce acid formation when incubated with saliva and to neutralize acids when mixed with water: ...
Johnston A W - - 1975
The amino acid analogue rho-fluorophenylalanine (PFPA) was found to have no mutagenic activity in the gamma system of bacteriophage T4. However, under standard conditions for 5-bromouracil (5-BU) mutagenesis, PFPA depressed the induced frequencies for both forward and reverse mutations. When the folate antagonist sulphanilamide (SU) was omitted from the mutangenic ...
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