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Sanglier J J - - 1990
By mutagenic treatment of a strain of Tolypocladium inflatum, a cyclosporin non-producing mutant was obtained which accumulated the characteristic building unit of cyclosporins, (4R)-4-[(E)-2-butenyl]-4-methyl-L-threonine (abbreviation Bmt; systematic name: (2S,3R,4R,6E)-2-amino-3-hydroxy-4-methyl-6-octenoic acid) in free form. The isolation from a culture filtrate was performed by extraction, chromatographic separation and final crystallization from methanol ...
Cornago M P - - 1990
The radiosensitizing effect of five glyoxal derivatives on the survival of TC-SV40 cells has been measured, under aerobic and hypoxic conditions. A toxicity study was previously performed in order to use nontoxic concentrations. The OER for the TC-SV40 cells was 2.74. None of the glyoxylic compounds showed radiosensitizing activity under ...
Glatt H - - 1990
L-Cysteine, glutathione and the therapeutically used L-cysteine precursor, N-acetyl-L-cysteine, induced strong mutagenic effects in Salmonella typhimurium (reversion of the his- strains TA97, TA92 and TA104), when tested in the presence of subcellular kidney preparations. The tyrosine metabolites, levodopa (an ortho-hydroquinone) and homogentisic acid (a para-hydroquinone) reverted various his- strains as ...
Fischkoff S A - - 1990
HL-60 human leukemia cells undergo terminal differentiation when cultured with butyric acid. To produce cells resistant to the maturation-inducing effects of butyric acid, two strategies were followed. First, HL-60 cells were mutagenized and cultured in soft agar with inducing concentrations of butyric acid. Four clones were isolated resistant to a ...
Gichner T - - 1990
Nitrosation of the carbamate insecticide propoxur at pH 3 and 37 degrees C was determined colorimetrically and found to be time- and sodium nitrite concentration-dependent. Nitrosated propoxur was mutagenic when exposed to the seeds of the higher plant Arabidopsis thaliana but the formation of nitrosopropoxur, the presumed mutagen, was inhibited ...
Skare K L - - 1990
Olestra, a mixture of hexa-, hepta- and octa-esters formed from the reaction of sucrose with long-chain fatty acids, was evaluated for its genotoxic potential in the Salmonella/mammalian microsome test, the L5178Y thymidine kinase (TK+/-) mouse lymphoma assay, an unscheduled DNA synthesis assay in primary rat hepatocytes, and an in vitro ...
Tikkanen L - - 1990
The mutagenic activities of the chlorinated butenoic acids recently identified in chlorinated drinking waters were determined by the Salmonella microsome assay and by the SOS chromotest. The Salmonella typhimurium tester strains TA97, TA98 and TA100 were used without and with S9 mix. In the SOS chromotest Escherichia coli PQ37 was ...
Pfau W - - 1990
The plant extract aristolochic acid (AA) has been used as a herbal drug in many cultures since antiquity. In 1982 AA was shown to be mutagenic and a strong carcinogen in Wistar rats. The crude mixture consists of five nitrophenanthrene carboxylic acid derivatives with aristolochic acid I [AA I; 8-methoxy-6-nitro-phenanthro-(3,4-d)-1,3-dioxolo-5-carboxyli ...
Schiestl R H - - 1990
Peroxisome proliferators are a class of non-mutagenic hepatocarcinogens, which induce a similar pleiotropic response such as hepatomegaly, proliferation of the peroxisomes in hepatocytes and hepatocarcinogenesis. Peroxisome proliferators are not detectable by the Ames assay and various other short-term tests. Recently a system for intrachromosomal recombination in yeast (DEL) has been ...
Przybojewska B - - 1990
The study was designed to investigate mutagenic and genotoxic properties of six synthetic dyes (Acid Green M, Acid Brown ZMSz, Acid Brown MSzCz, Anionic Black M, Anionic Brown ZM, Anionic Deep Red SM) obtained from All-Union Cancer Research Centre (AUCRC) in Moscow. To study mutagenicity and genotoxicity two short-term tests--Salmonella/microsome ...
Pérez A - - 1990
N-nitrosomorpholine biosynthesis and inhibition in mice treated with nitrate, morpholine and ascorbic acid, was studied by means of the mutagenic activity in urine samples. The preincubation method was used and Salmonella typhimurium TA 1535 was the test strain. The results suggest that N-nitrosomorpholine biosynthesis was carried out when the animals ...
Overvik E - - 1989
Creatine or one of 15 amino acids were mixed with minced pork before broiling at 200 degrees C. Total mutagenic activity and reversed-phase HPLC-separated mutagenicity profiles were determined for the crust and pan residue of all samples and also in the aerosol fraction of the smoke formed during cooking of ...
Yamaguchi T - - 1989
Some kinds of cheese were found to be mutagenic when some inhibiting substances were removed through extraction with MeOH-H2O and then treated with ion exchange resin. After this procedure, 16 types of commercial cheese out of 45 types tested showed significant mutagenicity on Salmonella typhimurium TA104, TA102 and TA97 without ...
Lord H L - - 1989
Dimethylnitrosamine (DMN) is activated to mutagenic species in the Ames test (Salmonella typhimurium strain TA100) by hamster hepatic S9 preparation. This S9 activity is induced by administration of ethanol to the animals. The organic solvents dimethylsulphoxide (DMSO) and N-methyl-2-pyrrolidinone (MP) inhibit this mutagenicity, apparently because they inhibit DMN demethylase activity ...
Hayatsu H - - 1989
When an aqueous homogenate of boiled rice was treated with nitrous acid at pH 3, direct-acting mutagens were formed. The presence of the mutagens was demonstrated by isolating the mutagenic fractions through blue-rayon adsorption, a method used to extract polycyclic compounds, and subsequent high-performance liquid chromatography (HPLC). The mutagens were ...
Wong K K - - 1989
Pyruvate formate-lyase (EC 2.3.1.54), a key enzyme in the anaerobic metabolism of Salmonella typhimurium, catalyzes the conversion of pyruvate to acetyl coenzyme A and formate. pfl::Mu dA operon fusions were isolated for the study of transcriptional regulation. pfl was transcribed both aerobically and anaerobically, but the activity increased about sixfold ...
Kasai H - - 1989
Two compounds forming oxygen radicals were isolated from heated starch by monitoring the potency to form 8-hydroxydeoxyguanosine from deoxyguanosine during purification procedures. These compounds were identified as hydroxymethylreductic acid and methylreductic acid. The former compound was mutagenic to Salmonella strains TA100, TA102 and TA104 and the latter compound induced sister-chromatid ...
Clonfero E - - 1989
Extracts of a leather widely used in the furniture and dress-making industries were tested for their mutagenic activity in the Salmonella/microsome assay. Extracts obtained after vigorous treatment of leather samples in a Soxhlet apparatus with toluene or ethanol were mutagenic in strain TA98 of S. typhimurium in the absence of ...
Rogers C G - - 1989
Domoic acid, a recognized neurotoxin derived from contaminated samples of the blue mussel (Mytilus edulis L.), was analyzed for mutagenicity at 2 loci and for 2 cytogenetic parameters in a hepatocyte-mediated assay with V79 Chinese hamster lung fibroblasts. Genetic end-points measured were: mutation to 6-thioguanine resistance at the HGPRTase locus; ...
Francis A R - - 1989
Five natural and two synthetic phenolic compounds were tested for their ability to suppress mutagenicity of aflatoxin B1 (AFB1) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Salmonella typhimurium tester strain TA100. Caffeic acid and eugenol were observed to inhibit mutagenicity of both the carcinogens, while chlorogenic acid was effective in the case of ...
Rossman R G - - 1989
The reactive metobolite responsible for benzene hematotoxicity and carcinogenicity is unknown. It can be hypothesized that the ultimate carcinogen derived from benzene metabolism might also act as a mutagen. This laboratory has recently developed a new assay that can detect mutagens of all types, using a single strain of bacteria, ...
Hoorn A J - - 1989
Dimethylglycine (DMG) and the chemically related amino acids glycine, sarcosine (monomethylglycine) and betaine (trimethylglycine) were tested in Salmonella typhimurium strain TA100 after treatment with sodium nitrite under acidic conditions using a modified Ames Salmonella/microsome assay as reported by Colman et al. (1980). The increase in the number of revertants observed ...
Byczkowski J Z - - 1989
Metabolism of resolved radioactive stereoisomer, [14C](+)-benzo-(a)pyrene-trans-7,8-dihydrodiol by highly purified soybean lipoxygenase plus linoleic acid was investigated. Trans-anti-7,8,9,10-tetrahydrotetrol, the product of hydrolytic breakdown of ultimate mutagenic benzo(a)pyrene-anti-7,8-dihydrodiol,9,10-epoxide, was detected as a major metabolite. The epoxidation, depended on the enzyme concentration and was inhibited by nordihydroguaiaretic acid. This study provides evidence on ...
Bala S - - 1989
The antimutagenic effect of 10 citrus fruit juices was observed against the mutagenicity of N-nitro-o-phenylenediamine (NPD) in TA97a and sodium azide in TA100 tester strains of Salmonella typhimurium using the Ames test. It was noticed that the juices of all these fruits reduced significantly the NPD and sodium azide induced ...
Mangold J B - - 1989
Azide mutagenicity in susceptible non-mammalian systems involves the requisite formation of L-azidoalanine, a novel mutagenic amino acid. The biochemical mechanism(s) of azidoalanine-induced mutagenesis, however, is not known. Previous studies of the structural requirements for azidoalanine mutagenicity suggested the importance of free L-amino acid character, and that bioactivation of azidoalanine to ...
Agarwal S C - - 1989
Fluka humic acid used as a model substrate in these studies was analysed for elemental and the oxygen-containing functional groups. It was chlorinated at C:Cl molar ratios of 1:1 and 1:0.3 and subsequently separated into molecular weight fractions by ultrafiltration. The freeze-dried, chlorinated humic acid and the respective molecular weight ...
Shibamoto T - - 1989
Since the development of short-term genotoxicity tests such as the Ames assay, the mutagenicity of Maillard reaction products has been tested extensively. Some products have exhibited strong activity. For example, one of the earliest studies demonstrated some mutagenic activity in a dichloromethane extract of a D-glucose/ammonia Maillard model system. Many ...
Crebelli R - - 1989
Urban air particulate extracts were assayed for mutagenicity in Salmonella typhimurium strain TA98 and in the nitroreductase deficient derivatives TA98NR and TA98/1,8DNP6. The results obtained indicate a low contribution of nitropyrenes from diesel exhausts to air particulate mutagenicity in the city of Rome. Fractionation of extracts into acidic, basic and ...
Przybojewska B - - 1989
This study was designed to investigate the mutagenic and genotoxic properties of ten dyes and four surface active compounds using Salmonella/microsome assay and the micronucleus test. Five of the investigated dyes (Acid Blue 7, Acid Green 16, Direct Black 19:1, Basic Red 22, Basic Orange 28) possessed mutagenic activity with ...
Pintauro S J - - 1989
Distiller's grains with solubles (DGS) was obtained from a commercial fermentation of 90% corn and 10% wheat for ethanol production. The DGS was freeze-dried and proximate analysis resulted in 17.6% protein, 5.5% fat, 3.0% ash, 17.3% moisture, 21.6% neutral detergent fiber, and 35% carbohydrate by difference. Fatty acid analysis and ...
Pasquini R - - 1989
The authors carried out biological monitoring of the mutagenic/carcinogenic hazards associated with exposure to bitumen fumes during paving operations, analysing some biological parameters in the urine of a group of exposed workers. The urine samples were studied for mutagenicity by the Ames test and for thioethers concentration. D-Glucaric acid urine ...
Kensese S M - - 1989
Weak mutagenic activity was detected in several commercially available edible palm and corn oils using liquid incubation bioassays with Salmonella typhimurium TA1537. Chromatographic fractionation of unrefined palm oil established that mutagenic activity was present in three fractions that also contained fatty acyl hydroperoxides. Similar weak mutagenic activity was also demonstrated ...
Jones R C - - 1989
A new class of low molecular weight, aminomethylimidazol-4-one (IQ-"like") mutagens have been produced by the reaction of creatinine with the amino acid L-threonine, in liquid-reflux models, mimicking cooking, of diethylene glycol:5% distilled water (2 h at 150 degrees C). Two mutagens, 2-amino-1-methyl-5-propylideneimidazol-4-one (AMPI) and 2-amino-5-ethylidene-1-methylimidazol-4-one (AEMI) were isolated and characterized ...
Badaev S A - - 1989
Humic acids in the form of potassium humate (KH), at concentrations exerting a strong inhibitory effect on the formation of N-methyl-N-nitrosourea (MNU) when present during the nitrosation of N-methylurea (MU) at pH 3, did not reduce the mutagenicity of preformed MNU in Tradescantia, clone 4430. The inhibitory effect of 20 ...
Pasquini R - - 1989
Mutagenic hazards related to occupational exposure to nitrous oxide and enflurane was studied in the personnel of five operating rooms using a coupled environmental and biological monitoring approach. The environmental monitoring revealed air concentrations of the two anesthetics exceedings the TLVs by 10-15-fold. These values were correlated individually with the ...
Weisburger J H - - 1989
Frying or broiling of meat or fish yields powerful genotoxic carcinogens such as 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and related amino-imidazo azaarene carcinogens. We have explored the mode of formation and inhibition of production of these carcinogens. Maillard reactions from precursor amino acids, hydroxyamino acids, and simple carbohydrates appear to yield reactive aldehydes ...
Shephard S E - - 1989
The diet contains a large number of constituents which can be nitrosated in the gastrointestinal tract (especially in the stomach) to potentially carcinogenic nitroso compounds (NOC). The nitrosation of food mixtures has been investigated with a number of assays, such as chemical analysis or detection of alkylating potential, mutagenicity and ...
Thompson E D - - 1989
Two linear polymers of acrylic acid (average molecular weight = 2,000 and 4,500) and one linear copolymer of acrylic and maleic acids (average molecular weight = 12,000) were tested for mutagenicity with the Salmonella mammalian microsome assay, the L5178Y mouse lymphoma assay at the TK locus, an unscheduled DNA synthesis ...
Barch D H - - 1989
Dietary ellagic acid has been shown to reduce the incidence of methylbenzylnitrosamine-induced esophageal carcinoma in the rat. Methylbenzylnitrosamine (MBN) is a naturally occurring carcinogen which requires cytochrome P-450 dependent activation to be mutagenic. We examined whether the reduction in tumor incidence observed with dietary ellagic acid was associated with alterations ...
Al-Ani F Y - - 1988
The activities of various concentrations of 4 acidity regulators (anhydrous citric acid, phosphoric acid, malic acid and lactic acid) used in food industries in Iraq was assayed using the Salmonella/microsome mutagenicity assay. None of the samples was mutagenic in the absence or in the presence of S9 to any of ...
Yamashita T - - 1988
The inhibitory influence of cyanuric acid on the virucidal effect of chlorine was studied. The time required for 99.9% inactivation of ten enteroviruses and two adenoviruses by 0.5 mg/l free available chlorine at pH 7.0 and 25 degrees C was prolonged approximately 4.8-28.8 times by the addition of 30 mg/l ...
Hayatsu H - - 1988
Dietary inhibitors of mutagenesis and carcinogenesis are of particular interest because they may be useful for human cancer prevention. Several mutagenesis inhibitors have been demonstrated to be carcinogenesis inhibitors also, e.g., ellagic acid, palmitoleic acid, and N-acetylcysteine. This means that the search for mutagenesis inhibitors may be useful for discovering ...
Ayrton A D - - 1988
Administration of the antimutagen anthraflavic acid to rats gave rise to significant increases in the hepatic microsomal O-deethylations of ethoxyresorufin and ethoxycoumarin, but not in the O-dealkylation of pentoxyresorufin nor in cytosolic glutathione S-transferase activity. Immunoblot studies of solubilized microsomes from anthraflavic acid-treated rats revealed that anthraflavic acid induced the ...
Ohta T - - 1988
Acetaminophen (paracetamol) showed mutagenicity to Salmonella typhimurium TA100 and TA98 either with or without S9 mix when treated with excess nitrite in acidic solution. The mutagen was isolated and identified as 4-acetylamino-6-diazo-2,4-cyclohexadienone. Mutation tests and product analysis by high-performance liquid chromatography, however, suggested that this type of mutagen was hardly ...
Hinton M - - 1988
In three experiments a solution of formic acid (Bioadd) was added to feed 'naturally' contaminated with salmonellas. In two of them no salmonella infections were demonstrated in broiler chickens given feed containing 0.6 per cent (w/w) of the formic acid solution for seven weeks and in the third the infection ...
Lin J K - - 1988
Reaction of N-2-fluorenylacetamide (2-FAA, CAS No. 53-96-3) with nitrous fume (N2O3) in glacial acetic acid at 0 degree C yields N-nitroso-N-2-fluorenylacetamide (N-NO-2-FAA), 3-nitro-N-2-fluorenylacetamide, N-nitroso-3-nitro-N-2-fluorenylacetamide and other compounds. N-NO-2-FAA is the major product (80%) and fairly stable at low temperature (-20 degrees C), but extremely labile at ambient temperature. The chemical ...
Mukherjee A - - 1988
The in vivo induction of sister chromatid exchanges and micronuclei formations by acute treatment with different concentrations of sorbic acid and by nitrite, individually and in combination, was studied in bone marrow cells of mice. A significant increase in the frequency of sister chromatid exchanges was only observed with the ...
Gichner T - - 1988
Naturally occurring para-aminobenzoic acid (PABA) inhibited the formation of N-methyl-N-nitrosourea (MNU) from a nitrosation mixture of N-methylurea and nitrite at pH 3. The suppressive effect of PABA on the formation of MNU is higher than that of ascorbic acid. The presence of the MNU was assayed by its mutagenicity in ...
Zesch A - - 1988
The lack of a first-pass effect for locally-applied substances is often not considered. This is especially true for such central nervous system agents as salicylic acid, hexachlorophene or caffeine which have a relatively low toxicity when applied orally. Manifestation of dermal irritation, such as a beginning rash or inflammation, are ...
Brewster M A - - 1988
Direct measurement of xenobiotic (foreign) chemicals is not always feasible as an exposure assessment,--owing to rapid metabolism, sequestration into fatty tissues, or lack of suitable assay methods. Furthermore, suspect exposures often involve complex mixtures of organics. In these circumstances, indirect biomarkers of exposure can be most helpful. This paper reviews ...
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