[en] The retention of uranium in mice following intravenous injection, the testicular clearance and the sperm abnormality caused by UO₂F₂ following testicular injection are descibed. The renal concentration of uranium is the highest of all tissues assayed, the skeleton one the second. The testicular clearance of uranium is of significant. UO₂F₂ in mouse testes can markedly induce sperm abnormality 13 and 36 days after administration and the sperm abnormality rate increases with the administered dose. The rate goes down 60 days after administration

[en] The radiogenetoxicological effects on the adult testis and the metabolic difference of tritiated thymidine between the testis of young and adult BALB/C mice were studied. When 0.037 MBq/g.b.w. of tritiated thymidine was given i.v. to mice, the initial burden of tritium in the adult was larger than that of tritium in the young. But the retention of tritium in testis of the young gradually become larger than that of tritium in the adult with the passing time. Tritiated thymidine which was incorporated into DNA of the male germ cell nuclei damaged the genetic materials and caused the rising of the rates of the dominant lethal and the dominant mutation which produced skeletal abnomalities in the offspring. The relationship between the dominant lethal mutation index (Y) and the injected activity of tritiated thymidine (I, MBq/g.b.w.) is described by Y = 74.13 + 80.20 I (r = 0.95). The relationship between the incidence of the dominant skeletal mutation in the offspring (B) and the injected activity is B = 0.16 + 0.079 I ( r = 0.85)

[en] Stimulative effect of low dose from ¹⁴⁷Pm radiation on DNA repair of germ cells in spermiogenesis stages was studied by alkaline elution technique. For labelling spermatids DNA, male BALB/C mice were given intra-testicular injection of ³H-TdR in advance. After 36 days of labelling, spermatozoa were sampled that is just the period of germ cells to mature. The period from intraperitoneal injection of ¹⁴⁷Pm to sampling spermatozoa was 12 days. After sperm cells have been lysed, 30 mL eluent was added in, then the flowrate was adjusted by the pumping speed. Finally, the DNA in filters and bottles were determined by radioactivity of labelled nuclides with a Backman liquid scintillation device. Results showed that after small dose of irradiation with 185 Bq/g of ¹⁴⁷Pm, an increase of sperm DNA on the filter was observed that was considerably higher than the control group. This indicates that low level radiation from ¹⁴⁷Pm has tendency to stimulate the capacity of DNA repair in spermiogenesis stages

[en] The inhibition of proliferation in bone tumor cells after simple or mixed irradiation by ²³⁵U, ¹⁴⁷Pm, ¹⁵³Sm was studied. Experimental results indicated that proliferation of bone tumor cells was significantly inhibited at 12 h∼24 h after a simple irradiation by ²³⁵U (128.4 Bq), ¹⁴⁷Pm (7.4 x 10⁵ Bq), and ¹⁵³Sm (7.4 x 10⁵ Bq) as well as mixed irradiation by ²³⁵U + ¹⁴⁷Pm (64.2 Bq + 3.7 x 10⁵ Bq), ²³⁵U + ¹⁵³Sm (64.2 Bq + 3.7 x 10⁵ Bq), ¹⁴⁷Pm + ¹⁵³Sm (3.7 x 10⁵ Bq + 3.7 x 10⁵ Bq). The findings show that the inhibition rate with mixed irradiation was more than that with simple irradiation

[en] The retentive peculiarity of soluble enriched uranium UO₂F₂ in subcellular level was studied by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO₂F₂ was chiefly localized in kidney, especially accumulated in nucleus of epicyte of kidney near-convoluted tubule. In liver cells, enriched uranium UO₂F₂ at first deposited in the nucleus and the cytoplasm, then accumulated in mitochondria selectively and lysosome as well. The electron microscopic autoradiographic study showed that the dynamic retention of radioactivity of enriched uranium UO₂F₂ in skeleton rose steadily throughout the exposure. Enriched uranium UO₂F₂ chiefly deposited in nucleus and mitochondria of the osteoblasts as well as osteoclasts

[en] A study was made on the retention of soluble enriched uranium UO₂F₂ in ultrastructure by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO₂F₂ was mainly localized in kidneys, especially accumulated in epithelial cells of proximal convoluted tubules leading to degeneration and necrosis of the tubules. In liver cells, enriched uranium UO₂F₂ at first deposited in nuclei of the cells and in soluble proteins of the plasma, and later accumulated selectively in mitochondria and lysosomes. On electron microscopic autoradiographic study it was shown that the dynamic retention of radioactivity of enriched uranium UO₂F₂ in skeleton increased steadily through the time period of exposure. Enriched uranium UO₂F₂ chiefly deposited in nuclei and mitochondria of osteoblasts as well as of osteoclasts

[en] The purpose of the present study is to ascertain the injury effects on central and peripheral immune cells by fission product of heavy nucleus (¹⁴⁷Pm) and the radioprotective effect of lymphokines, rIL-1 and rIL-2 on ¹⁴⁷Pm-irradiated immune cells. Experimental results show that internal contamination of ¹⁴⁷Pm could injure the proliferation of central and peripheral immune cells. At 2nd day after ¹⁴⁷Pm irradiation, the proliferation of bone marrow cells, thymus cells as well as spleen B lymphocytes was inhibited. While the ³H-TdR incorporation was depressed, it should be noted that the injury effects of ¹⁴⁷Pm on proliferation of central and peripheral immune cells was perfectly or partially restored by rIL-1 or rIL-2. Both rIL-1 and rIL-2 showed radioprotective effect on central and peripheral immune cells irradiated by ¹⁴⁷Pm

[en] Apoptosis in human acute lymphoblastic leukemia cell line Molt-4 cell and macrophage cell line Ana-1 cell could be induced by fission fragment ¹⁴⁷Pm. The cumulative absorption dose of ¹⁴⁷Pm in cultural cells through different periods were estimated. By using fluorescence microscopy and microautoradiographic tracing it can be found that Molt-4 and Ana-1 cells internally irradiated by ¹⁴⁷Pm, displayed an obvious nuclear fragmentation and a marked pyknosis in immune cell nuclei, as well as DNA chain fragmentation and apoptotic bodies formation. The microautoradiographic study showed that ¹⁴'7Pm could infiltrate through cell membrane and displayed membrane-seeking condensation in cells. At the same time, the membrane and displayed membrane-seeking condensation in cells. At the same time, the membrane-bounded apoptotic bodies were observed. Experimental results in recent study provide evidence that Molt-4 and Ana-1 immune cells undergo apoptosis while internally irradiated with ¹⁴⁷Pm

[en] The present study engages in determining whether low doses of internally deposited enriched uranium UO₂F₂ could change the responsiveness of splenic lymphocytes and monocytes to subsequent higher doses of enriched uranium UO₂F₂. BALB/c male mice were injected with 0.01, 0.1, 1 or 10 μg/kg body weight of UO₂F₂. Three days later the mice were injected with 2 x 10⁴ μg/kg body weight of UO₂F₂. The animals were sacrificed at twenty-four hours after injection of higher doses of UO₂F₂. The results show that the splenic monocytes and lymphocytes exposed to 0.1-10 μg/kg or 0.01-1μg/kg of UO₂F₂ respectively become less susceptible to subsequent higher doses of UO₂F₂; that is, immune cells exposed to low doses of UO₂F₂ become adapted so that less cytoimmune damage represented by variation of unscheduled DNA synthesis and interleukin-1 is induced by higher doses of UO₂F₂. The adaptive response occurred only in a limited range of low doses of UO₂F₂. The size of the induction dose seemed to be inversely related to the radiosensitivity of different immune cells

[en] The present study engages in determining whether low dose irradiation of ¹⁵³Sm could cut down the responsiveness of cellular survival to subsequent high dose exposure of ¹⁵³Sm so as to make an inquiry into approach the protective action of adaptive response by second irradiation of ¹⁵³Sm. Experimental results indicate that for inductive low dose of radionuclide ¹⁵³Sm 3.7 kBq/ml irradiated beforehand to cells has obvious resistant effect in succession after high dose irradiation of ¹⁵³Sm 3.7 x 10² kBq/ml was observed. Cells exposed to low dose irradiation of ¹⁵³Sm become adapted and therefore the subsequent cellular survival rate induced by high dose of ¹⁵³Sm is sufficiently higher than high dose of ¹⁵³Sm merely. It is evident that cellular survival adaptive response could be induced by pure low dose irradiation of ¹⁵³Sm only