Cytogenetic studies on the effect of feeding mice with stored wheat grains treated with malathion

The cytogenetic effect of malathion residues in wheat grains stored for different periods of time (4, 12, 24 weeks) was evaluated in Swiss mice. The studies included: (1) chromosomal aberrations analysis in bone-marrow and spermatocyte cells; (2) chromosomal aberrations and sister chromatid exchange (SCE) analysis in spleen cell culture from mice fed with stored wheat grains. The tested doses were 8.36 (applied dose), 25.08 and 41.80 mg malathion kg⁻¹ wheat grains. The results demonstrated that the cytogenetic effect induced in different mouse tissues by malathion residues was dose-dependent and increased with increasing of both feeding and storage periods.Feeding mice with wheat grains stored for 4 weeks had a non-significant effect with respect to the induction of chromosomal aberrations or SCEs. Significant chromosome damage and increase of SCEs were observed in mice fed with wheat grains stored for 12 weeks. The maximum effect was recorded in mice fed for 12 weeks with the grains treated with the highest tested dose and stored for 24 weeks. However, mitomycin C i.p.-injected in mice at 1 mg kg⁻¹ body weight (b.w.) (positive control) induced a higher effect. The percentage of chromosome aberrations reached 13.60±0.98, 13.60±0.77 and 11.73±0.98 (P<0.01) in bone-marrow, cultured spleen cells and spermatocytes, respectively. The significant increase of abnormalities in spermatocytes was seen for univalent formation only, predominantly of the sex chromosomes. The frequency of SCEs was 10.76±0.62 per cell (P<0.01) in cultured spleen cells compared with 5.46±0.45 per cell for control and 14.66±0.54 per cell for the positive control.The obtained results indicate that malathion residues in stored wheat grains have potential genotoxic effect in mice under the conditions tested.     

Cytogenetic studies in patients treated with penicillamine.

Cytogenetic studies were performed on bone-marrow cells from 11 patients with rheumatoid arthritis treated with penicillamine. One of the patients was studied while developing a granulocytopenia and thrombocytopenia. The findings show that penicillamine had no chromosome-damaging effect as estimated by the micronucleus test and by the number of structural chromosomal aberrations.     

Cytogenetic studies in mice treated with the jet fuels, Jet-A and JP-8

The genotoxic potential of the jet fuels, Jet-A and JP-8, were examined in mice treated on the skin with a single dose of 240 mg/mouse. Peripheral blood smears were prepared at the start of the experiment (t = 0), and at 24, 48 and 72 h following treatment with jet fuels. Femoral bone marrow smears were made when all animals were sacrificed at 72 h. In both tissues, the extent of genotoxicity was determined from the incidence of micronuclei (MN) in polychromatic erythrocytes. The frequency of MN in the peripheral blood of mice treated with Jet-A and JP-8 increased over time and reached statistical significance at 72 h, as compared with concurrent control animals. The incidence of MN was also higher in bone marrow cells of mice exposed to Jet-A and JP-8 as compared with controls. Thus, at the dose tested, a small but significant genotoxic effect of jet fuels was observed in the blood and bone marrow cells of mice treated on the skin.     

Cytogenetic effects of malathion insecticide on somatic and germ cells of mice

Male mice dermally exposed to single or multiple treatment (5 days/2 weeks) showed that the ability of malathion to induce chromosome aberrations in somatic (bone marrow) and germ cells (primary spermatocytes) was related to the type of treatment and dose used. Statistically significant increases of chromosome aberrations in bone marrow cells occurred after single treatment (500 and 2000 mg/kg body wt) when chromatid gaps were included and after multiple treatment (250 and 500 mg/kg) when they were excluded. No dose-response relationships were observed for either treatment. In germ cells, malathion induced a significant increase of univalents in both types of treatment but structural chromosome aberrations were induced only by multiple treatment. Malathion induced a significant decrease of the mitotic indices in the bone marrow.     

Growth of wheat seedlings raised from the grains treated with 28-homobrassinolide

An experiment was conducted under controlled conditions, in which grains of wheat (Triticum aestivum L. cv. Raj-3077) were soaked in 0, 1, 3 and 5 μM aqueous solutions of 28-homobrassinolide (HBR) for 4, 8 and 12 hours. The seedlings raised from the grains pre-treated with HBR possessed significantly higher leaf number, fresh and dry weight·plant⁻¹, nitrate reductase (NR,E.C. 1.6.6.1) and carbonic anhydrase (CA, E.C. 4.2.1.1) activities on 25 and 35 days, after sowing. The soaking of the grains in 3 μM concentration for 8 or 12 hours produced the most vigorous seedlings.     

Cytogenetic effect of malathion in in vitro culture of human peripheral blood

Chromosomal aberrations, sister-chromatid exchanges and mitotic indices were observed in human peripheral leukocytes, treated with four different concentrations of malathion (0.02, 0.2, 2 and 20 μg/ml), an organophosphate pesticide, added to the culture medium at 0, 24 and 48 h after culture initiation. These cultures showed a dose-dependent increase in the frequency of chromosomal aberration as well as sister-chromatid exchanges. There was a significant decreases in mitotic index at all concentrations.     

Cytogenetic studies on wild house mice from Belgium

The present status of Robertsonian karyotype variation in populations of wild mice from Belgium is presented. Two fusions, Rb(4.12)1Nam and Rb(5.10)3Nam, were identified in the central plain of this flat country. Surrounding this region only mice with the usual 2n=40 karyotype occurred. From the distribution pattern some possible relationships to other Rb populations from Europe are discussed.     

Cytogenetic studies of mice exposed to styrene by inhalation.

The data for the in vivo genotoxicity of styrene (STY) are equivocal. To evaluate the clastogenicity and sister-chromatid exchange (SCE)-inducing potential of STY in vivo under carefully controlled conditions, B6C3F1 female mice were exposed by inhalation for 6 h/day for 14 consecutive days to either 0, 125, 250 or 500 ppm STY. One day after the final exposure, peripheral blood, spleen, and lungs were removed and cells were cultured for the analysis of micronucleus (MN) induction using the cytochalasin B-block method, chromosome breakage, and SCE induction. Peripheral blood smears were also made for scoring MN in erythrocytes. There was a significant concentration-related elevation of SCE frequency in lymphocytes from the spleen and the peripheral blood as well as in cells from the lung. However, no statistically significant concentration-related increases were found in the frequency of chromosome aberrations in the cultured splenocytes or lung cells, and no significant increases in MN frequencies were observed in binucleated splenocytes or normochromatic erythrocytes in peripheral blood smears.     

Cytogenetic studies on the effect of chronic gamma irradiation onVicia faba

Vicia faba seeds (cv. Giza 1) were planted in the Inshas gamma radiation field where they were chronically irradiated during the whole life of the plant. The percentage of the induced abnormal P.M.Cs, as well as the frequency of abnormal P.M.Cs in the different meiotic stages were proportional with the given doses. The main types of chromosome aberrations were anaphase and telophase bridges, fragmentation and lagging chromosomes. The nearest plants to the source showed an inhibition of shoot growth, flower and seed sterility and irregular branching. At the dosage levels used irradiation had no effect on pollen fertility. Seeds of the 1st filial generation were used for both mitotic and meiotic studies. The percentage of the mitotic abnormalities was proportional with the doses. The most dominant type of anomaly was the presence of micronuclei in the different stages of mitosis and in the resting cells. Irradiation affected also other types of anomaliese.g. lagging chromosomes, fragments, bridges...etc. Meiosis, and pollen fertility (2nd generation) were normal.     

Cytogenetic studies on gas station attendants.

Forty-nine gas station attendants employed to pump fuel and 24 controls were studied cytogenetically. This type of worker is occupationally exposed to fuel fumes and to automotive vehicle emissions. Chromosome analysis showed a significantly higher frequency of chromosome deletions among the gas station attendants than a control group. Taking into account the relationship between clastogenicity and increased cancer risk, we may consider these workers to form a risk group.     

Cytogenetic and dominant lethal studies on captan.

Possible mutagenic activity of captan was investigated by in vitro and in vivo cytogenetic studies and by the dominant lethal study in mice. In vitro cytogenetic study with cultured human diploid cells revealed a significant increase in the frequency of cells showing stickiness and a severe mitotic inhibition at concentrations of 3.0 and 4.0 microgram of captan per ml. although no chromosomal aberrations were observed. In in vivo cytogenetic study, no chromosomal aberrations were induced in the bone marrow cells of rats treated orally with captan at a single dose of 500, 1000 or 2000 mg/kg or at five consecutive doses of 200, 400 or 800 mg/kg/day. Dominant lethal study also failed to show any mutation induction after treatment of male mice with daily oral dose of 200 or 600 mg of captan per kg bw for five days.     

Cytogenetic studies in 12 patients with itai-itai disease.

Among 12 Itai-Itai disease patients examined, 8 patients showed a remarkably high frequency of chromatid aberrations, whereas the other 4 patients showed a much lower frequency of such aberrations, although a significant number of stable type aberrations was observed also in the latter patients. The frequencies of aneuploid cells of all 12 patients were significantly higher than those of the controls. The abnormalities were found in 50-hour and 72-hour cultures, from which it can be concluded that the aberrations occurred in the blood stem cell of the patients. In addition to these structural and numerical aberrations, satellite associations of the D and G group chromosomes were often observed.     

Cytogenetic effect of 238Pu alpha radiation on the germ cells of male mice

A study was made of the yield of reciprocal translocations in stem spermatogonia of mice exposed to alpha-radiation (238Pu) and whole-body acute and chronic gamma-radiation within a wide range of doses and dose-rates. The frequency of reciprocal translocations induced by a single intraperitoneal administration of plutonium nitrate was relatively low and independent of the dose 1.5-18 months after the effect. The yield of the reciprocal translocations induced by chronic effect of gamma-radiation was appreciably lower than that observed after acute irradiation with the same dose and grew linearly with dose. The RBE of alpha-radiation was 10-20 with respect to chronic effect of gamma-radiation.     

Kinetochore-staining of spermatid micronuclei: studies of mice treated with X-radiation or acrylamide.

The rodent spermatid micronucleus (MN) assay was used in conjunction with immunofluorescent techniques to distinguish kinetochores in MN following exposure of mice to X-radiation or acrylamide. After either treatment, modest increases in kinetochore-positive MN were observed. Spermatids which had been exposed during meiotic prophase to X-rays (400 cGy) had approximately 10-fold increases in MN compared to controls; up to 15% of the MN observed were kinetochore-positive. Following acrylamide treatment of meiotic prophase cells, there was a doubling of spermatid MN over baseline levels, approximately one-third of which were kinetochore-positive.     

Cytogenetic studies of workers from the rubber industry.

Lymphocytes from 21 vulcanizers from a tire factory were analyzed for the presence of chromosome aberrations (CAs), sister-chromatid exchanges (SCEs) and for proliferation indices (PIs). An increase in the frequencies of CAs and SCEs and a decrease in PIs were observed. Cytogenetic parameters were correlated with age, smoking habits, and duration of occupational exposure. From the present study it can be concluded that cigarette smoking enhances the genotoxic effects of mixtures of chemicals to which workers in the rubber industry are exposed.     

Cytogenetic studies in 100 couples with recurrent spontaneous abortions.

The reported incidence of translocations in couples with recurrent spontaneous abortions ranges from 3% to 31% (average 9.3%). We report 100 couples in whom no reciprocal translocation carriers were ascertained.