[en] The radiogenotoxicological effect such as chromosome aberrations in germ cells and abnormalities in sperm induced by fission fragment ¹⁴⁷Pm in different periods after iv this radionuclide to mice was observed. Results indicated that chromosome aberrations of spermatogonium were induced by ¹⁴⁷Pm. The chromosome aberration rates and polyploid cells number were increased with the periods of contamination of ¹⁴⁷Pm. At the same time ¹⁴⁷Pm also induced chromosome fragments and translocations of primary spermatocyte. It was shown that polyvalent of primary spermatocyte appeared only after 10 days of ¹⁴⁷Pm contamination

[en] Anoxia, continual γ-irradiation or anoxia in combination with continual γ-irradiation could increase the LPO contents of livers, spleens and hearts of mice. The enhancements of SOD activities of livers, spleens and hearts of mice in anoxia group and γ-irradiation group were observed. Anoxia in combination with continual γ-irradiation could result in the decrease of SOD activities of livers, spleens and hearts of mice

[en] The purpose of the present study is to ascertain ¹⁴⁷Pm retention in organism and its radiogenotoxicological effect through varying intervals of internal exposure. Especially, accumulation of ¹⁴⁷Pm in testis on induction of chromosome aberrations in germ cells and abnormalities in sperm. Results indicated that after iv ¹⁴⁷Pm through 50d observation. The retention data in testis were well described by an exponential expression: R(t) = 0.1872 x e^-0.0066t. Studies indicated that the absorption dose in testis was increased when the internal exposure of ¹⁴⁷Pm was prolonged. Internal contamination of ¹⁴⁷Pm can induce chromosome aberrations in germ cells and abnormalities in sperm. Among the type of chromosome aberrations of spermatogonium induced by ¹⁴⁷Pm including gap, chromatid breakage, chromosome breakage and translocation, as well as polyploid spermatogonium. The chromosome aberration rates and polyploid cells were elevated when the period of contamination of ¹⁴⁷Pm were prolonged. At the same time chromosome fragment and translocations of primary spermatocyte also induced by ¹⁴⁷Pm. Studies showed that polyvalent of primary spermatocyte were enlarged only through 10 days of ¹⁴⁷Pm contamination. Abnormalities in sperm induced by ¹⁴⁷pm-non-hook sperms were predominant

[en] Calyculin A was added into the human blood samples irradiated by ⁶⁰Co γ-ray at different doses (0, 0.25, 0.5, 1.0, 2.0, 3.0 Gy) after 46 h irradiation. Chromosome condensations induced by Calyculin A were observed and compared with conventional chromosome aberrations. The results showed that the mitotic index of PCC induced by Calyculin A was much higher than those obtained with conventional colchicine block or G₀-PCC by fusion; and there was a linear relation between the fragments of PCC induced by Calyculin A and the dose

[en] Objective: To study toxic effect of radon exposure on bone marrow cells of mice to explore mechanisms of radon-induced leukemia. Methods: Twenty-four mice were randomly divided into four groups, one control group and three experimental groups with the cumulative doses of radon at 27 WLU(low dose group), 54 WLm(middle dose group) and 105 WLm(high dose group). Levels of superoxide dismutase (SOD), lipid peroxidation (LPO), ³H-TdR incorporation and superoxide free radical in bone marrow cells were measured to reflect the lipid peroxidation induced by radon. Results: The level of superoxide free radicals of the control group shows marked increase compared to other three experiment groups, the difference between them all have statistical significance (P<0.05). But reproduction ability of marrow cells, namely cpm shows different change trend. The cpm value of 52 WLM group is higher than that of the control group and 27 WLM group, but the cpm value of 105 WLM group is lower than that of the control group and 52 WLM group (P<0.05). Apparent decrease of SOD of all experiment groups are observed compared to the control group, but as for LPO, contrary situation appear (P<0.05). The relative changes of 105 WLM group is most obvious. Conclusion: Damages of oxidation and DNA synthesis are observed in bone marrow cells in the high dose group. (authors)

No abstract available

[en] The PCC fragment rates induced by Calyculin A was used to study the degree of chromosome damage during the radiotherapy using iodine-131 on thyroid carcinoma patients, and compared with conventional aberrations. The results showed that PCC fragment rates of induced by Calyculin A were more precise than general chromosome assay technique. (authors)

[en] Objective: To explore the relationship between the high radiosensitivity of AT5BIVA fibroblast line and apoptosis. Methods: AT5BIVA(AT) fibroblasts and GM0639(GM) fibroblasts were exposed to 0-6 Gy ⁶⁰Co γ-rays. The effects of ⁶⁰Co γ-ray irradiation on the proliferation of AT and GM fibroblasts, expressed by percentage of ³H-TdR incorporation in DNA, were measured by liquid scintillation counter. The spontaneous and radiation-induced apoptosis rates were determined by flow cytometry at 0, 24, 48, and 72 h after exposure to ⁶⁰Co γ-rays. Results: The percentage of ³H-TdR incorporation in DNA in AT and GM fibroblasts decreased with radiation dose, and the ³H-TdR incorporation in AT fibroblasts decreased more quickly than that in GM fibroblasts. The relationships between ³H-TdR incorporation rate and dose were fitted as S_AT0.9718e^-0.6855D(R²=0.9950) and S_GM=1.0928e^-0.3731D (R²=0.9777) for AT and GM fibroblasts, respectively. The spontaneous apoptosis rate in AT fibroblasts was higher than that in GM fibroblasts; the radiation-induced apoptosis rate in AT and GM fibroblasts gradually increased with dose at 24th hour after exposure to 2-6 Gy ⁶⁰Co γ-rays, and radiation-induced apoptosis rate in the former was higher than that in the latter; the apoptosis rate in both AT and GM fibroblasts showed time-dependent increase during 0-72nd hour after exposure to 2 Gy ⁶⁰Co γ-rays; the difference of the apoptosis rates between AT and GM fibroblasts gradually enlarged with dose and reached a significant level at 72nd hours after the exposure Conclusion: The high radiosensitivity of AT fibroblasts was closely related to its spontaneous and radiation-induced apoptosis

[en] In order to study the effect-dosage relationship between the PCC induced by Okadaic acid and the IR dosages, human peripheral blood in vitro was irradiated by X-rays at different doses (0, 0.5, 1.0, 2.0, 3.0, 5.0Gy) cultivated for 48 hours and added with Okadaic acid two hours before the end of culture. Chromosome aberrations frequencies was analyzed and compared with that induced by the conventional chromosome assay and their dose-response curves were fitted. The results show that the mitotic index of the PCC induced by Okadaic acid is higher than that of the conventional chromosome assay. And the fragment rate of chromosome condensation induced by Okadaic acid has a favorable linearity relationship with external radiation doses. (authors)

[en] Objective: To study the high radiosensitivity of fibroblast cells (AT5BIVA cells) from the skin of the patients of ataxia-telangiectasia (AT). Methods: Using conventional chromosome aberration analysis method, chromosome aberration frequence (CAF) of AT cells and GM cells exposed to ⁶⁰CO γ-rays was observed at doses of 0, 1, 2, 3 and 4 Gg, compared with that of GM 0639 (GM cells) from the skin of the normal subject. The difference of CAF between AT cells and GM cells was analyzed, and dose-response curves were established. Results: After exposed to 0, 1, 2, 3 and 4 Gy ⁶⁰CO γ-rays, the radiation-induced level of CAF was significantly higher in AT cells compared with GM cells (P<0.05). In the two cell types, CAF has a positive correlation with dose, and their linear regression equation is Y=a + bX. The slope of the CAF linear regression equation of AT cells is larger than that of GM cells (P<0.05). Conclusion: The radiosensitivity of AT cells is significantly higher than that of GM cells. AT cells is extremely sensitive to radiation. (author)