Responses of Aquatic Organisms to Cyanobacteria and Elodea in Microcosms.

The aim of the present study is investigation of the impact of mass development of cyanobacteria and Elodea on population characteristics (abundance, biomass, fecundity) and "health" parameters (the state of embryos, heart rate, and thermal resistance) of aquatic invertebrates in experiments with controlled conditions. In July-August 2018, in four variants of microcosms, the conditions were modeled characteristic of the coastal zone of the Rybinsk Reservoir in the period of mass development of cyanobacteria. Mass species were placed in microcosms of planktonic (with domination (80%) Daphnia longispina) and bottom animals (Unio pictorum, Gmelinoides fasciatus, Asellus aquaticus), as well as Elodea canadensis. In the variants with cyanobacteria, the toxic microcystins LR were revealed (24-53% of the sum of toxins, or from 6.6-66.5 µg/L). The presence of cyanobacteria (Aphanizomenon flos-aquae, Microcystis aeruginosa, and Gloeoitrichia spp.) influenced structural parameters of plankton: the quantity to green algae decreased, small-sized crustaceans increased. Influence of cyanobacteria caused reliable changes in parameters of aquatic animal from those of the control: thermal resitance of mollusks and amphipods decreased, time of restoration of heart rate after loads (salinity test) in mollusks increased; in amphipods, individual fecundity decreased, frequency of abnormalities and of mortality of embryos increased. The presence of Elodea intensified these effects. Thus, mass development of cyanobacteria and Elodea influences ecological-physiological parameters of aquatic animals, decreasing their adaptivity to natural stresses and deteriorating the quality of the progeny.

[Analysis of Phytoplankton in Tsimlyansk Reservoir (RUSSIA) for the Presence of Cyanobacterial Hepato- and Neurotoxins].

Although the water bodies of southern Russia experience the most extreme effects of cyanobacterial blooms, molecular genetic data on the composition of toxigenic cyanobacteria in this region have been absent. Screening for the genes responsible for the synthesis of hepatotoxins (microcystins and cylindrospermopsin) and neurotoxins (anatoxin-a and saxitoxins) in cyanobacteria from the Tsimlyansk reservoir on the Don River was carried out. The presence of microcystin-producing Microcystis and Planktothrix populations, as well as of cyanobacteria capable of synthesis of a neurotoxin anatoxin-a was revealed by polymerase chain reaction (PCR). A hypothesis of the presence of anatoxin-a-producing Planktothrix rubescens population in the phytoplankton of the Tsimlyansk reservoir is proposed. The obtained PCR data were confirmed by the results of enzyme-linked immunosorbent assay (ELISA) and liquid chromatography/mass-spectrometry (LC/MS). Anatoxin-a and five microcystin variants were identified in the phytoplankton biomass.

[Allelic polymorphism of the IL-2and IL-4 genes in herpesvirus infection].

Herpesvirus infection is accompanied by imbalance of peripheral mononuclear production of cytokines, by polarizing an immune response by the Th2 pathway. The homozygous TT genotype of T330G polymorphism in the IL-2 gene is an immunogenetic factor that has a protective activity against susceptibility to herpesvirus infection. The risk of progression, the recurrent course of the infection and its poor outcome is positively associated with the heterozygous TG genotype in the IL-2 gene T-330G promoter region and with the homozygous CC type and C allele in the IL-4 gene C-590T promoter region.

[Status of the erythron during growth of induced tumors]. / Sostoianie éritrona v protsesse rosta indutsirovannykh opukholei.

The authors conducted complex (with the use of radionuclide, cytospectrophotometric, electron microscopic, interfermometric, and other methods) examination of the morpho-functional condition of the central and peripheral erythron links in rats during the development of tumors induced by 20-methyl-cholanthrene administration. It was found that increased hemolysis of mature circulating red cells plays the principle role in the pathogenesis of anemia developing in the experimental animals. The early periods of the hemolysis may be detected in the latent period of cancerogenesis.