[Effect of abiotic and biotic factors on the structural and functional organization of the saline lake ecosystems in Crimea].

Decrease of both zooplankton and zoobenthos species richness and a trend toward decrease of their biomass with the salinity increase was recorded in the hypersaline lakes of Crimea. The most of structural and functional characteristics of macrobenthos is positively correlated with abiotic and biotic characteristics of those lakes. Abundance, biomass, productivity of macrobenthos and ration of non-predating macrozoobenthos decrease with salinity increase, while they increase with the depth and growth of amount of chlorophyll a and primary production. Macrozoobenthos portion in the total zooplankton and macrozoobenthos biomass decreases with both salinity and depth increase. Zooplankton community is less controlled by abiotic factors as compared to macrozoobenthos, while the former's species number significantly decrease with salinity increase. Effect of salinity on zooplankton biomass is slightly significant, unlike that of macrozoobenthos. Comparison of total amount of rations of zooplankton and macrozoobenthos with amount of primary production indicates intense trophic interactions in the lakes under study.

[Morphological and cytochemical properties of the human glioblastoma T98G cells during the monolayer culture]. / Morfologicheskie i tsitokhimicheskie svoistva kletok glioblastomy cheloveka linii T98G pri kul'tivirovanii v monosloe.

The study was carried out with the aim of determination of morphological and cytochemical properties of human glioblastoma T98G cells in monolayer culture. Using light microscopic and immunocytochemical techniques, the glioblastoma cell line studied was shown to have low susceptibility to the effects of environmental factors and changes in culture conditions as well as high proliferative activity. All T98G cells were demonstrated to have positive nuclear reaction for p53 protein. An ability of T98G cells for spontaneous caspase 3-mediated apoptosis was shown using the antibodies against activated caspase 3. The data obtained suggest that glioblastoma T98G cell line could be used as a convenient model for testing the capacity of natural substances and of pharmaceutical agents that are being developed for the selective induction of caspase 3-mediated apoptosis.

[Karyotype characteristics of continuous cell lines. II. The variability and balance of the chromosome set of M-HeLa cells]. / Kharakteristika kariotipa postoiannykh kletochnykh linii. II. Izmenchivost' i sbalansirovannost' khromosomnogo nabora kletok M-HeLa.

A cytogenetic study of three M-HeLa sublines of common origin but differing in cultivation technique was undertaken with G-, C- and Ag-staining. The sublines differ in their normal and marker chromosome contents. The marker chromosomes were completely identified in all the sublines. This enabled us to employ a new cytogenetic method of karyotype reconstruction. The reconstruction of normal chromosomes from fragments entering into the marker composition allowed to determine the total content of normal chromosomes in each cell. This total content does not vary somewhat substantially within one subline in spite of the intercellular karyotype heterogeneity, and this proves the balance of genomes within a given subline. The reconstructed karyotypes of separate cells made it possible to build a generalized reconstructed karyotype of each subline. In this karyotype obligatory and minimal should be the human diploid chromosome set. Moreover, in each subline the 1st and 5th chromosomes are extracopied. In addition to this stable component, occurring in all the cells, in some cells chromosomes 7 9, 12, 14, 16 and 17 may also be extracopied. The marker formation involved mainly centromeric regions of the 1st, 3rd and 5th chromosomes. With the existing chromosome variability the selection plays the main role in the formation of cell populations cultivated in different ways.

[Karyotype of continuous cell lines. I. The karyotype variability of M-HeLa cells cultured by static and roll-tube methods]. / Kariotip postoiannykh kletochnykh linii. I. Izmenchivost' kariotipa kletok M-HeLa pri staticheskom i rollernom sposobakh kul'tivirovaniia.

A comparative investigation of three M-HeLa sublines, being of common origin but differing in cultivation technique (roller or static), was undertaken using G- and C-banding. It is shown that the M-HeLa sublines of a non-clonal origin differ in the level of their karyotype variability as compared to most human and animal lines studied earlier. A definite set of normal and marker chromosomes, as well as a typical karyotype, was revealed for either subline tested. The change of the static technique of cultivation into the roller one was accompanied with changes in the modal class, with the increase in polyploid cell number and proliferation index. It is postulated that the change of cultivation technique may result in selection of defined cell types due to the pre-existed karyotype variability.