[The effect of treatment of chrysotile with chloride iron (III) on the effect of genomic instability in cultured human lymphocytes].

All forms of asbestos are carcinogenic to humans, that caused the prohibition of its use in Europe, America, etc. However, the unique physical and chemical properties of asbestos and many opportunities for its applications in various industries and human activities require the creation of new technologies to. Analysis of genomic instability in human lymphocytes in a large range of doses (micronucleus test with cytochalasin B showed a decline of core indicators of genome instability (frequency of dividing cells with cytogenetic damage, asymmetry in the distribution of the genetic material in mitosis, proliferative activity) incubation of cells with asbestos modified chloride iron, as compared to the initial sample. These data are consistent with the results of analysis of the intensity of neutrophil chemiluminescence of luminol by exposure of human blood samples studied. Based on the findings made some practical recommendations to the protocol cytogenetic analysis of genomic instability of people exposed to asbestos.

[Chrysotile-asbestos induces cytogenetic effects in the rat's mesothelium in vitro and in vivo].

Under cultivation of rat peritoneal mesothelial cells in vitro in them there are appeared signs of the genomic instability, evidencing their transformation: increasing of the number of both binucleated cells with micronuclei and polynuclear cells and the increase of sizes and polymorphism. Asbestos greatly accelerates this process. Asbestos-induced carcinogenesis in vivo is accompanied in pleural mesothelium in the rats there also revealed with similar signs of genomic instability and cellular transformation.

[Carcinogenic and mutagenic activity of chrysotile, processed with iron chloride (III)].

This work is devoted to the study of the role of iron ions in the carcinogenic and mutagenic activity of chrysotile. For this aim natural chrysotile was treated with ferric chloride (III), washed, crushed and intratracheally introduced into Wistar rats. When administered to rats intact chrysotile induced mesotheliomas in 27,9 + 4,6% of cases, and chrysotile modified with ferric chloride - in 1,3 +/- 1,3%. Mutagenicity of the same samples was studied in the micronucleus test when administered intraperitoneally to mice Fl (CBA x S57Bl6). Polychromatic erythrocytes in the bone marrow were investigated 24 hours after intraperitoneal administration. The frequency of polychromatic erythrocytes with micronuclei was decreased from 7,4 +/- 0,18 by 1000 due to the action of chrysotile, from 2,8 +/- 0,42 for 1000 after the introduction of a modified sample. It is hypothesized that the ferric chloride modifies the surface of asbestos fibers that reduces the induction of free radicals which are the primary cause of and carcinogenic effects of chrysotile.

[To a question on the impact of nanoparticles of metals present in the aquatic environment, on bacteria and continuous cell lines HEp-2 and BGM].

Promising application of nanoparticles and nanomaterials is the creation of sanitary hygienic means of new generation used for disinfection of water and indoor surfaces of mass use, furniture, sanitary technical equipment by virtue of modifying traditional materials to bring them effective biocidal properties, and for the development of methods in vitro for assessment their toxicity In this paper the possibility of the use various forms of silver, copper and aluminum as disinfectant for bacterial test organisms in the aquatic environment and assess their toxicity on biological models of continuous culture of BGM cells (a stable line of African green monkey kidney cells) and HEp-2 (Human epithelial type 2 (HEp-2) cells, derived from a human laryngeal carcinoma) is considered.

[Detection of potentially carcinogenic compounds persisting in atmospheric air and having high priority for hygienic regulation].

The algorithm for the choice of potentially carcinogenic compounds (PCS) among emitted into air and results of the study, undertaken for realization of this algorithm are presented. The investigation was carried out in Magnitogorsk - Russian town of black metallurgy - in frames of the other study, aimed to evaluation of the influence of atmospheric pollution on children's health and genomic instability. The 11 PCS for further profound study of biological activity were selected out of more than 300 PCS, persisting in the air. The carcinogenic activity for 6 compounds out of these 11 ones was already have been found out before, that testifies correctness of the created approach and its adequacy for detection PCS in atmospheric air.

[Toxic and genetic risk assessments in children of Gornaya Shoria].

This comprehensive study assessed a number of environmental factors that were potentially able to induce genotoxic effects in man. A set of radiological, physicochemical, and bioindication techniques was used to estimate the quality of water, air, and soil in the places of residence and education of children and adolescents from the boarding school of the town of Tashtagol and schoolchildren from the village of Krasnoye, Kemerovo Region. Excess radon levels in the air of living spaces and classes, a small excess of the maximum allowable concentration of gross forms of heavy metals in individual soil samples, and high toxic effects in the Drosophila gametes exposed to air samples were revealed in the Tashtagol children having higher genotoxic effects in the lymphocyte than those in the Krasnoye village ones. The findings suggest that the marked genotoxic effects recorded over a long time in the lymphocytes of children and adolescents living in Tashtagol may be associated with the complex influence of the above factors. It is north supplementing further investigations by an extended chemical analysis of water, air, snow, and soil samples taken in the places of residence and education of children.

[Potential relationship between mutation process induced by low doses of ionizing radiation, and positional dynamics of chromosomes in nuclei of eukaryotic cells]. / O vozmozhnoi sviazi mutatsionnogo protsessa, indutsirovannogo malymi dozami ioniziruiushchei radiatsii, i pozitsionnoi dinamikoi khromosom v iadrakh kletok éukariot.

The mutation process has many stages. The information presented in this article suggest that a cell exposed to low LET radiation in the low-dose range (up to 1 cGy) must almost completely repair all spontaneous and radiation-induced DNA lesions. But reparation of DNA double-stranded breaks (DSB), which are the basis of genome instability has peculiarity. We have shown that the mechanisms of action of low doses (which initiate natural antimutagenic reactions of resting cells--an adaptive response) are associated with chromosome loci (centromere) movement in a cell nucleus. We suggest that the movement of chromosome loci in cell nucleus is the fundamental mechanism for repair of DSB and switching of the transcription of gene (it is known that in case of lymphoid cells Ikaros-complexes repressor is colocolizated with centromere loci); in particular, of nucleolar transcription activities because the latter is dependent on centromere arrangement. Because the movement of chromosome loci in both the mitotic cycle and under adapting dose on resting cells is much the same it could be assumed that in latter case the cells also lose their functional characteristic for differentiated resting cells. Under chronic exposure to low doses the functional changes can be the cause of organic changes if adapting dose affects the sufficient part of the cells. The role of cells of evolutional or ontogenetic reserve in mutation process is considered.

[Procedure for complex toxico-genetical investigations]. / Metodologiia provedeniia kompleksnykh genetiko-toksikologicheskikh issledovanií.

A biomonitoring system is proposed, which involves measurement of environmental genetoxicants, determination of mutagenic accumulation in biological substrates of human beings and the severity of genetic abnormalities in their somatic cells. The toxicogenetical monitoring system includes the assessment of the examinees mental status. The results of application of the system are given by using as an example two Yaroslavl (machine-building and oil-processing) plants.

[Value of estimation of stress during human toxico-genetical investigations]. / Znachenie otsenki stressa pri genetiko-toksikologicheskikh issledovaniiakh na liudiakh.

The paper presents the monitoring results of the genetic and mental status of workers from 2 plants of Yaroslavl. The groups of the examinees were formed in terms of unhealthy working conditions and residence in clean or polluted areas of the city. The individuals working under harmful and living under unfavourable environmental conditions were found to be more commonly acute or chronically stressed or fatigable than the control workers. Those under stress were shown to be more responsive to environmental genetic toxic agents. Whether psychological training may be used to form groups at high genetic risk is discussed.

[Study of antimutagenic properties of the citrus drink Tampico]. / Izuchenie antimutagennykh svoistv napitka "Tampiko".

Oral administration of the orange drink Tampico containing additionally vitamins A (12.7 mg/l), B (1.81 mg/l), C (86.9 mg/l) to FICBAxC57B1/6 mice has been shown to stabilize erythrocytic membranes and reduce chromosomal aberrations in the murine bone marrow cells induced by cyclophosphamide. There are experimental data on the effects of Tampico on the rate of reparative synthesis in peripheral lymphocytes and blood levels of malonic aldehyde in the mice exposed to model psychoemotional stress.

[The antimutagenic action of a preparation of a species-nonspecific interferon]. / Antimutagennoe deistvie preparata vidonespetsifichnogo interferona.

The human gene-engineering gamma-interferon agent gammaferon (GF) is demonstrated to lower the level of chromosomal aberrations and release of cyclophosphamide-induced micronuclei in murine bone marrow cells. A model is suggested for regulating the ratio of single to multiple chromosomal aberrations induced by cyclophosphamide by altering the antioxidative status of the body. With this model, it was shown that the antimutagenic effects of GF were caused by two factors: the antioxidative effect of the corresponding placebo and the unknown (but none antioxidative) effect of gamma-interferon itself. Erythrocytic resistance to in vitro oxidative disturbance in the Fe2+/system was used as an integral measure of the body's antioxidative status.

[Factors which determine the oxygen status of ascites tumors]. / Faktory, opredeliaiushchie kislorodnyi status astsitnykh opukholei.

A study was made of the oxygen status of cells of an Ehrlich ascites tumor at different stages of its development. Radiosensitivity of the tumor cells was determined with a reference to the yield of micronuclei. It was shown that the major role in the ascites tumor oxygenation is played by its volume rather than cellularity.

[Effect of the pH of the lysing solution on the sedimentation properties of the nucleoid of intact and irradiated Ehrlich ascites tumor cells]. / Vliianie pH liziruiushchego rastvora na sedimentatsionnye svoistva nukleoida intaktnykh i obluchennykh kletok astsitnoi opukholi Erlikha.

A study was made of the sedimentation properties of Ehrlich ascites tumor cell nucleotide obtained by cell lysis in 1.95 M NaCl, 0.1 M EDTA, 0.02 M tris, and 0.5% triton X-100, at pH 5.0 and 8.0. It was shown that the nucleotide obtained at pH 5.0 has a more compact structure than that obtained at pH 8.0. Irradiation of cells leads to relaxation of the nucleotide decreasing the rate of its sedimentation in a neutral sucrose gradient. The influence of irradiation on the sedimentation properties is more pronounced with pH 5.0 than 8.0.