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The effect of blue light damage (445-455 nm, 4 J/cm2) to retinal pigment epithelium (RPE) subcellular structures was investigated in 4 age risk groups (9, 25, 40 and 52 weeks) of Japanese quail Coturnix japonica by light and electron microscopy. The indicator of biological aging of RPE was age-related accumulation of lipofuscin granules: 5-6-fold increase in their quantity increasing by 5-6 times in quails at 52 weeks. The main photo-induced changes observed after 24 h of the photo radiation were located in the blood-retinal barrier, such as loss of homogeneity of Bruch's membrane, disorganization of basal processes, deformations of the nuclei and mitochondria shapes. Those effects ofphotobleaching were more expressed in young birds. But for the older 52-week age birds it was not so noticeable, because their retinal pigment epithelium structures had disorders which were similar to those in younger birds after photodamage.

Rat liver was examined by transmission electron microscopy after a single intravenous injection of nanosized magnetite suspension (0.1 g (Fe(3)O(4))/kg body weight). Magnetite particles were found in Kupffer's cells and hepatocytes. Accumulation of the particles by these two cell types was different. Morphometry of magnetite-containing granules in Kupffer's cells and nanoparticle agglomerations in hepatocytes was carried out. The ultrastructure of Kupffer's cell granules was described and the mechanism of penetration of nanosized magnetite particles into the cells was suggested. Nanosized magnetite particles were not completely eliminated over 40 days after a single injection.

In this review recent data describing stress granules are summarized. Stress granules are specific RNA-containing structures in the cytoplasm of living cells which arise under stress conditions (e. g. heat shock, UV irradiation, energy depletion and oxidative stress). It became evident that stress granules accumulate non-canonical 48S initiation complexes and contain mRNA with associated proteins, small ribosomal subunits and some initiation factors. Stress granules are depleted with ternary complex and large ribosomal subunit. It's proposed that eIF2alpha phosphorylation and ternary complex decrease can be a trigger for stress granule formation. Shuttling nuclear and cytoplasmic RNA-binding protein TIA-1 plays a crucial role in this process. It's proposed that TIA-1 forms prion-like aggregates, and these aggregates are scaffolds for other components of stress granules. Cytoskeletal structures facilitate the accumulation of stress granule components in local cytoplasmic sites. Investigation of process of stress granule formation is important for understanding of cell reaction to stress and translation regulation mechanisms.

In this review, the problem of hepatitis B is considered as related to the recent data on the biology of the viral agent, on the pathogenesis of disturbances that it causes in an organism as well as on accompanying deviations in its immune system. Special attention is paid to mechanisms of hepatitis B virus (HBV) persistence and the role of regulatory lymphocytes of NK/NKT system in this process. Some problems in further studies are specified.

Protein composition of mesoglea of the scyphomedusa Aurelia aurita was revealed in SDS-PAGE. Some major bands are visible in mesoglea of a mature medusa: 30, 45-47, 85 kDa, three bands between 100-200 kDa, and several bands with molecular weights > 300 kDa. Polyclonal antisera RA45/47 against protein 45 kDa were raised. RA45/47 react with 45-47 kDa protein in mesogleal sample and protein 120 kDa in mesogleal cells on immunoblot. Immunohistochemical analysis of A. aurita histological sections of young and mature medusae showed antigen localization in mesogleal cell granules and in the apical part of ectodermal cells. In mature medusae, the antigen was localized also in elastic fibers. We can conclude that in A. aurita mesogleal cells, along with ectodermal cells, take part in the formation of extracellular matrix of mesoglea.