[Cytogenetic effects of alpha-irradiation due to incorporated 239Pu]. / Tsitogeneticheskie éffekty alpha-oblucheniia inkorporirovannykh 239Pu.

Intravenous injection of plutonium dioxide with 1-2 microns particle sizes in amount of 92.5, 46.3 and 23.2 kBq/kg of body mass increased the yield of chromosome aberrations in bone marrow cells of rats by 3.7, 2.3 and 1.7 times, correspondingly, in comparison with the spontaneous level. The model of chromosome aberration dependence on dose of radionuclide was developed based on the experimental results.

[A comparative evaluation of the efficacy of different methods for the decorporation of plutonium from the respiratory organs]. / Sravnitel'naia otsenka éffektivnosti razlichnykh metodov dekorporatsii organov dykhaniia ot plutoniia.

The behavior of plutonium in the organism and the mechanism of formation of absorbed doses in rats of different age were studied in a comparative aspect. The efficiency of CaDTPA depending on the animal's age and the usage was estimated. Under similar conditions, the efficiency of early single injections of CaDTPA to rat cubs was 2.3 (skeleton) or 3.3 (liver) times lower than that for mature rats. Attempts of modifying the kinetics of low-transportable plutonium-239 by stimulation of pulmonary alveolar macrophages failed.

[Comparative study of hazards of energy plutonium and standard Pu-239 using non stochastic effects]. / Sravnitel'naia opasnost' énergeticheskogo plutoniia i standartnogo 239Pu po nestokhastichesksim éffektom.

In experiment with rats it was found that the "energy" Pu is more toxic than standard 239Pu when entered endotracheally. The comparison was made by the non-stochastic effects. The toxicity in respiratory system and blood system was 1.8 and 1.6 times higher when calculated per 1sGy of absorbed dose and 1.6 and 1.1 times higher when calculated per 1kBg/kg of the amount taken, respectively.

[State of cellular immunity effectors of the lung in inhalation exposure to low-transportable Pu-239]. / Sostoianie populiatsii éffektorov kletochnogo immuniteta legkikh pri ingaliatsionnom postuplenii nizkotransportabel'nogo 239Pu.

The reduction of populations of lung cell immunity effectors as well as changes in their cytotoxic and phagocytic activity was observed in rats after inhalation exposure to polymeric 239Pu. Dose-response curves described as a function of absorbed dose of alpha-irradiation in lung.

[Effects of pentacin on subcellular distribution of Pu-239 nitrate in the lungs of rats]. / Vliianie pentatsina na subkletochnoe raspredelenie 239Pu nitrata v legkikh krys.

The method of differential centrifugation has shown that 26% of 239Pu-nitrate injected intratracheally, is detected in cells in 3 h (24.4% of Pu is bound with subcellular organellae). In 24 h the nuclear fraction acquires a paramount importance in Pu binding. In the hyaloplasm 239Pu is distributed equally between low molecular (32.9-42.9%) and high molecular (54.1-55.2%) proteins. Pentacine decreases the level of Pu in the lungs, in the sum of subcellular fractions and in the sum of organellae, but produces no noticeable action on the level of the radionuclide in hyaloplasmic proteins though promotes certain redistribution of the radionuclide between low- and high molecular proteins.

[238Pu body distribution in dogs after intravenous administration and early complexon therapy]. / Raspredelenie 238Pu v organizme sobak posle vnutrivennogo vvedeniia i rannei kompleksonoterapii.

The paper is concerned with the assessment of the level and concentration of 238Pu in different organs and tissues of dogs after iv injection of 238Pu-citrate at the amount of 92.5 kBq.kg-1 and during early complexon therapy. Ninety per cent of Pu detected in the body was shown to be deposited in the skeleton and liver in the ratio 4.5:1. The concentration of 238Pu in per cent to 1 g of tissue in the critical organs (the skeleton, liver, bone marrow) was (28.7--46.9) X 10(-3)%. The concentration of the radionuclide in the organs and tissues regarded as uncritical, was 1-2 orders lower: the endocrine organs--(0.7--7.5) X 10(-3)%, the lymph nodes--(3.8--5.4) X 10(-3)%, the G. I. tract portions--(1.05--1.5) X 10(-3)%, the CNS portions--(0.1--2.0) X 10(-3)%; the kidneys, muscles, heart, spleen and lungs--(0.63--8.8) X 10(-3)%. Early use of octacine or pentacine decreased Pu concentration in all investigated organs and tissues 2 +/- 0.06 times on an average. The efficacy of octacine was no inferior to that of pentacine.

[Reduction in the level of 239Pu in pulmonary tissue using octacin]. / Snizhenie soderzhaniia 239Pu v legochnoi tkani s pomoshch'iu oktatsina.

Octacin, injected 30 min before 239Pu administration, reduces the level of radioactivity in the lungs, subcellular fractions, and in highly molecular hyaloplasmic proteins. Octacin by its efficacy is similar to pentacin.

[The antibody-producing cell count of rats exposed to polymeric 239Pu]. / Soderzhanie antiteloobrazuiushchikh kletok u krys pri deistvii polimernogo 239Pu.

In experiments with Wistar rats a study was made of the content of antibody-forming cells (AFC) in the spleen at remote times (3 to 12 months) after intravenous injection of 239Pu(IV) in doses of 166, 55, and 18 kBq/kg body mass. The doses absorbed in the central and peripheral immunity organs were defined. Pronounced spleen hypoplasia and profound inhibition of humoral immunity were displayed 1 year after the injection of a small amount of the radionuclide. AFC deficiency in animals was amounted to 11-32 per cent throughout the entire period of observation.

[Frequency of structural chromosome aberrations in the hepatocytes of rats exposed to polymeric 239Pu]. / Chastota strukturnykh povrezhdenii khromosom gepatitsitov krys pri deistvii polimernogo 239Pu.

Intravenous injection of polymeric 239Pu(IV) nitrate (166.5, 55.5 and 18.5 kBq/kg body mass) to Wistar rats was shown to produce biphase changes in the frequency of hepatocyte chromosome aberrations. The increase in the structural damages to chromosomes at later times of observation was a pronounced function of radiation dose. The absence of such a dependence at early times was evidently due to the elimination of damaged liver parenchyma cells.

[Disorders of hematopoiesis induced by plutonium-239 dioxide]. / Narushenie gemopoéza pri deistvii dvuokisi plutoniia-239.

A large-dispersed plutonium 239 dioxide intravenously administered to rats in doses of 92.5, 46.3, 23.2 kBq/kg of body mass was shown to impair haemopoiesis which was manifested by a more profound injury to erythropoiesis, a stable increase in the number of bone marrow lymphocytes, a remote development of lymph node hypoplasia, and reduction of functional neutrophil and lymphocyte pools.

[Structural chromosomal damages in myelokaryocytes exposed to plutonium-239 dioxide]. / Strukturnye povrezhdeniia khromosom mielokariotsitov pri deistvii dvuokisi plutoniia-239.

Plutonium 239 dioxide, with particle sizes of 1-2 micron, injected to Wistar rats intravenously in doses of 92.5, 46.3, and 23.2 kBq/kg body mass, increased the frequency of chromosome aberrations in myelokaryocytes by 3.7, 2.3 and 1.7 times, respectively, compared to spontaneous levels.

[Plutonium localization in the nuclear fraction of lung cells]. / Lokalizatsiia plutoniia v iadernoi fraktsii kletok legochnoi tkani.

Pu localization in the nuclear fraction isolated from rat pulmonary tissue cells was studied by histoautoradiography. It was found out that 24 h after intratracheal administration of Pu, 93.8% of the radionuclide (of the total number of tracks) were bound with nuclei. It was also shown that 64.8% of Pu were fixed by large nuclei, 42.2% by small nuclei. Pu content in nuclei varied within broad ranges: from single tracks up to high density "stellae".