Showing papers in "Mutation Research Letters in 1991"

TL;DR: Modifying the DGGE by using constant denaturant gels corresponding to the specific melting domains of certain DNA fragments leads to increased resolution of mutants as fragments differing in as little as 1 base pair migrate with a consistently different mobility through the whole gel allowing separations of several centimeters.

TL;DR: Over time, asthenospermia and necrospermia diminished but the abnormal spermatozoa (teratospermia) continued.

TL;DR: When cells were exposed to 1 cGy X-rays 24 h after phytohemagglutinin stimulation, the yield of mutations induced by a 300 cGyX-ray dose given 16 h later was reduced by approximately 70% from the control level of X-ray-induced mutations, indicating that this previously described adaptive response to low dose X- rays also results in lymphocytes becoming refractory to the induction of gene mutations.

TL;DR: In metaphase-I spermatocytes, the frequencies of various types of abnormal chromosomes did not differ between the selenium-deficient and control groups, indicating that seenium day be an essential constituent for sperMatogenesis in mice.

TL;DR: The genotoxicity of beryllium, gallium and antimony compounds was studied with the rec, Salmonella mutagenicity and SCE assays and Sb2O3, slightly soluble in water, was positive in both the rec assay and the SCE assay at very low doses.

TL;DR: The present results indicate that acetaldehyde is metabolized within human lymphocytes, and that alcohol consumption during treatment with drugs that inactivate aldehyde dehydrogenase may cause a further increased incidence of acetaldehyde-induced SCE and concomitant lesions.

TL;DR: Using busulfan as a mutagen both the chromosome aberration test and the micronucleus test showed strong anticlastogenic action when L. casei, Omniflora or yoghurt (with living bifiobacteria) were given orally at the same time as the mutagen.

TL;DR: Results provide evidence that both biochemical parameters and the overall capacity of fish liver to activate or detoxify certain mutagens can be assumed to be sensitive indicators of exposure to mixed organic pollutants in the marine environment.

TL;DR: Acrylamide monomer (AA), injected into male mice at the maximum tolerated dose of 5 x 50 mg/kg (24-h intervals), significantly increased the specific-locus mutation rate in certain poststem-cell stages of sperMatogenesis, but not in spermatogonial stem cells, which conforms to Pattern 1 in earlier classification of chemicals according to the sPermatogenic stage at which they elicit maximum response.

TL;DR: The cytotoxic and mutagenic effects of the synthetic auxin 2,4-dichlorophenoxyacetic acid on shallot root tip cells and on V79 Chinese hamster fibroblast cells were examined and compared.

TL;DR: Fifteen gasoline pump mechanics and 15 controls were investigated with the lymphocyte micronucleus assay and also with differential count of leukocytes in the peripheral blood, finding the leukocyte count was significantly higher in the gasoline-exposed group.

TL;DR: The dose-effect curves revealed the same tendency as the authors found in various previous investigations and support the assumption that repair enzymes could be triggered by a certain amount of damage to the DNA.

TL;DR: The results support the initial assumption that polyploidy is largely a consequence of the disturbed assembly of microtubules, and DES was more active than its monomethyl ether in disturbing microtubule formation within cells.

TL;DR: The results of the micronucleus test in bone marrow showed that it was vitamin C that caused the antimutagenic effect against bichromate, in both rats and guinea pigs.

TL;DR: The results suggest that measurement of MN in vivo after irradiation can be used as an in vivo dosimeter, however, precise dosimetry is probably affected by factors such as kinetic changes in different lymphocyte populations and possibly by in vivo factors which influence sensitivity of cells to radiation.

TL;DR: The data clearly suggest the validity of the methodology in pointing out the role played by antileukemic agents in inducing somatic genetic damage and a marked increase in basal micronucleus frequency, due to therapy.

TL;DR: It was evident that the administration of 250 and 500 mg coffee/kg body weight could significantly inhibit the in vivo genotoxicity of these carcinogens.

TL;DR: The results show the usefulness of this rat model for simultaneous evaluation of two cytogenetic endpoints in the same animal and indicate that assessment of MNPCE frequency in the bone marrow of male rats may be an appropriate model for screening test substances for in vivo clastogenic activity in this species.

TL;DR: Results show that chlorophyllin, at concentrations of 2.5 mg/plate or less, completely or almost completely inhibited the mutagenicity of 2AA, AFB1, BaP, MNNG and solvent extracts of CD, DE and RW, which substantiate the antimutagenic efficacy of chlorophylla against chemicals and complex mixtures.

TL;DR: Monoepoxybutene and diepoxybutane were highly effective in inducing SCEs at concentrations of 0.1-1 microM both in the presence and in the absence of S9 mix, and at higher concentrations the response was more pronounced without S9Mix.

TL;DR: The distribution of monoadducts and biadducts induced in the supF tRNA gene carried by the shuttle vector pZ189, after exposure to 8-methoxypsoralen (8-MOP) plus a double UVA (365 nm) irradiation is determined.

TL;DR: The results support the suggestion that MC modulates the genotoxicity of indirect-acting mutagens by inhibiting certain forms of the cytochrome P-450 enzymes required for activation of premutagens like CP and AFB.

TL;DR: Aniline gave a positive response in the mouse bone marrow micronucleus assay 24 h after the second of two intraperitoneal injections of 80% of the median lethal dose (MLD).

TL;DR: Results indicate that bleeding mice prior to chemical treatment is a simple method for increasing the sensitivity of the micronucleus assay.

TL;DR: Smoke condensates of woods used for food preservation and aromatization in Nigeria were tested for mutagenic activity using Salmonella typhimurium TA98 and TA100 and induced dose-dependent increases in the number of His+ revertants mainly with S9 mix.

TL;DR: An antagonistic response indicates anticlastogenic activity of BC against cyclophosphamide, which acts as an antimutagen/anticarcinogen in several test systems.

TL;DR: It is suggested that ascorbate can induce the loss of several plasmids of S. aureus, and that the levels of antibiotic resistance are also affected by the presence of this compound.

TL;DR: Results show that omeprazole has genotoxicity and cell proliferative activity in the rat glandular stomach mucosa.

TL;DR: The results obtained in experiments showed that cycloheximide did not induce frameshift or base-pair substitution mutations in S. typhimurium regardless of metabolic activation, and cyclo heximide had only toxic effects but no increase of mitotic gene conversion was noticed under the conditions of the experiment.

TL;DR: The results show a pattern of response which is qualitatively similar for both compounds and this indicates that its mutagenicity depends on both nitroreduction and transacetylation.