[Detection of micronuclei in desquamating cells of the human oral mucosa in the territory of South Vietnam]. / Registratsiia mikroiader v slushchivaiushchikhsia kletkakh slizistoi rotovoi polosti cheloveka na territorii Iuzhnogo V'etnama.

The possibility of applying the micronucleus test to estimate changes in chromatin structures of somatic cells of South Vietnam inhabitants exposed to with phytotoxic substances (Agent Orange) in the 1960s was investigated. Remote medical and biological consequences of the action of dioxin-containing phenoxyherbicides on man were studied. In inhabitants of Bin Mi Village (Shongbe Province), which had been intensely bombed with Agent Orange, the epithelium of the oral cavity showed a considerable increase in the occurrence of cells with damaged chromatin structures (P < 0.01).

[Use of the micronucleus test for assessing the ecological situation in regions of the Astrakhan district]. / Ispol'zovanie mikroiadernogo testa dlia otsenki ékologicheskoi obstanovki v raionakh astrakhanskoi oblasti.

The effect of industrial and agricultural contamination of the environment on the formation of micronuclei in peripheral blood cells of the lake frog Rana ridibunda P. was studied. Simultaneously, the influence of mutagenic contaminants on the human gene pool in Astrakhan' and Astrakhan' oblast' was analyzed. Frogs were trapped in three raions of Astrakhan' oblast': the villages of Trudfront and Verkhnii Buzan and Oblivnoi Island. Peripheral blood smears were prepared and cells with micronuclei and nuclear material were analyzed. Cells with micronuclei were 94.5 times more abundant in frogs from ecologically unfavorable Oblivnoi Island than in animals from Trudfront and 1.2 times more plentiful than in frogs from Verkhnii Buzan.

[The insulin-secreting and proliferative activity of established islet cells in the presence of sulfonylurea]. / Insulinsekretiruiushchaia i proliferativnaia aktivnost' perevivaemykh ostrovkovykh kletok v prisutstvii sul'fonilmocheviny.

Exponentially growing rat islet cells (RINr) and hamster islet cells (HIT T-15) were incubated in presence of tolbutamide (10-1000 microM), gliclazide (0.1-10 microM) or glibenclamide (0.01-10 microM) for 15 hrs. Accumulation of insulin in culture medium was estimated by RIA. Effects of sulfonylureas (SU) on cell proliferation were assessed by 3H-thymidine (3H-T) incorporation into cellular DNA. All of SUs used stimulated insulin production in RIN and HIT cell cultures (with an exception of tolbutamide, which markedly suppressed insulin secretion in HIT cells at 1000 microM). 3H-T incorporation into RIN cells was elevated only in presence of gliclazide (10 microM), whereas tolbutamide at 1000 M significantly inhibited RIN cell proliferation. Gliclazide (0.1 microM) and glibenclamide (0.01-10 microM) enhanced 3H-T incorporation into HIT cells. Further detailed investigations of mechanisms of SU effects on islet cell reproduction will be of use for designing optimal strategy of hypoglycemizing therapy of diabetes mellitus.

[Introduction of regulatory subunits of cAMP-dependent protein kinase type II in ZTZ cells with the use of erythrocyte ghosts]. / Vvedenie reguliatornoi sub''edinitsy cAMP-zavisimoi proteinkinazy II tipa v kletki ZTZ s primeneniem tenei éritrotsitov.

The dynamics of distribution of the regulatory subunit of cAMP-dependent protein kinase II following protein injection into 3T3 cells was studied. The cAMP-binding component of protein kinase was injected into the cells, using erythrocyte ghosts. The conditions for protein encapsulation into erythrocyte ghosts were elaborated. The optimal detergent concentrations, incubation time and conditions of vesicular closure following protein injection were selected. The above method provides for a high (50-55%) yield of the erythrocyte ghost-encapsulated protein with a minimum loss of enzymatic activity. Fusion of erythrocyte ghosts containing the labeled protein with 3T3 cells was carried out. Using the cytoradiography technique, the dynamics of distribution of the radiolabeled regulatory subunit within the cell was analyzed. It was demonstrated that after the regulatory subunit has reached the cytoplasm, the protein is translocated into the nucleus and is pooled there is the vicinity of the nucleoli.