The development of cadmium resistance in an Indian muntjac cell line has been investigated. The parent cell line is highly sensitive to cadmium ions. Resistance was obtained by continuous growth of cells in low levels of cadmium with stepwise increments. Four cell lines were developed with resistances of between 50- and 200-fold greater than that of the parental line. Early in the development o...

Cultures of whole blood from pregnant women (4 to 6 months), premenopausal women, postmenopausal women, and normal men were grown in the presence of varying concentra tions (1 x 1o-@M, 2 x 1O@M, and 4 x 1O'@M) of diethylstil bestrol (DES), a synthetic estrogen and known carcinogen, to see if It had sex-related cytogenetic effects. DES induced sister chromatid exchanges in lymphocytes from pregn...

Frequency of sister chromatid exchanges (SCEs), which has been considered an index to the synthetic and sharp genotoxic and clastogenic potencies, was examined by using the infant lymphocytes postnatal of around ten months, in order to evaluate the genotoxic or clastogenic potency of exposures to PCBs and dioxins through the breast milk. SCE frequency (mean +/- S.D.) as the control culture trea...

Spontaneous and mutagen induced sister chromatid exchange (SCE) frequencies have been studied in nine patients with multiple sclerosis and in nine age and sex matched healthy controls. The incidence of spontaneous SCE in lymphocytes of the MS patients was significantly greater, by about 50%, than in those of the control subjects. When exposed to mitomycin C (MMC) or ethyl methane sulfonate (EMS...

In the present study the effect of Centella asiatica L. extract was studied against the genotoxic doses of ethinylestradiol on human lymphocytes culture. The different doses of C. asiatica L. extract i.e. 1.075×10 -4 , 2.125×10 -4 and 3.15×10 -4 g/ml were treated separately with 5 μM of ethinylestradiol. Similar treatments were given with 10 μM of ethinylestradiol. The treatments result in a si...

Hydroquinone, a metabolite of benzene, and acetaldehyde, a metabolite of ethanol, induce sister chromatid exchanges (SCEs) at relatively high concentrations. Because both compounds are reported to form glutathione conjugates, experiments were carried out to see if there was a synergistic effect when lower concentrations of both chemicals were added to human lymphocyte cultures. Hydroquinone (40...

Cadmium is a toxic metal that inactivates DNA-repair proteins via multiple mechanisms, including zinc substitution. In this study, we investigated the effect of Cd(2+) on the Bloom protein (BLM), a DNA-repair helicase carrying a zinc-binding domain (ZBD) and playing a critical role to ensure genomic stability. One characteristics of BLM-deficient cells is the elevated rate of sister chromatid e...

Ubiquitination of proliferating-cell nuclear antigen (PCNA) at K164 by RAD6/RAD18 has a key role in DNA damage tolerance in yeast. Here, we report on the first genetic study of this modification in a vertebrate cell. As in yeast, mutation of K164 of PCNA to arginine in the avian cell line DT40 results in sensitivity to DNA damage but, by contrast, the DT40 pcnaK164R mutant is more sensitive tha...

In the mouse pre-B-cell line 18-81, cells can switch production in vitro from immunoglobulin mu chain to gamma 2b chain. The gene encoding the gamma 2b chain is created by a rearrangement of the mu gene. This rearrangement always takes place within a homolog. In cells with a gamma 2b gene, most of the time the gene segment encoding the constant region of the mu chain is deleted, but often the r...

The male contraceptive agent gossypol was found to induce a dose related increase of DNA strand breaks in human fibroblasts in vitro at concentrations of 5 to 40 micrograms/ml. The effect was reduced in the presence of 2% fetal calf serum. A weak but reproducible increase in the SCE frequency was found in human lymphocytes treated for 1 hour in serum-free medium with 0.04 to 4 micrograms/ml of ...