Synthesis and cytotoxic properties of anomeric 5-substituted 3'-azido-2',3'-dideoxyuridines]

Glycosylation of trimethylsilyl derivatives of 5-benzyloxymethyl- and 5-hydroxymethyluracil with 3-azido-2,3-dideoxy-5-O-benzoyl-D-ribofuranosyl chloride (prepared from ethyl 3-azido-2,3-dideoxy-5-O-benzoyl-D-ribofuranoside) and subsequent deacylation gave in both cases a mixture of anomeric 3'-azido-2',3'-dideoxy-5-benzyloxymethyl-or 5-hydroxymethyluridines. The anomers were separated by preparative TLC and their structures were studied by UV, IR and 1H-NMR spectroscopy. It is shown that 1-(3-azido-2,3-dideoxy-alpha-D-ribofuranosyl)-5-benzyloxymethyluracil has cytotoxic activity in vitro: in 10(-5)-10(-4) M concentrations it inhibits the thymidine incorporation into DNA of CaOv cells on 78.6-95.2%.     

Production in an Actinomyces levoris culture under the action of an actinophage specific to it of variants with stable preservation of its resistance to the phage]

Act. levoris 28, an organism producing levorin was treated with an actinophage virulent to it. Variants of the organism were isolated from the secondary growth of the culture. As a result of lysogenization with the above phage the variants acquired stability to it which was preserved during the further generations. In the previous experiments carried out by the authors the variants isolated from the secondary growth of the culture after its exposure to the same phage lost their stability to the phage as a result of loosing the prophage by it during the subsequent passages. The phage stable variants did not differ from the initial culture either in the activity of levorin or the levorin composition. The phages found in the initial culture 28, and the virulent mutant were identical with respect to the particles morphology and antigenic properties which confirmed their relation.     

Genetic diversity of Besermyans inferred from mitochondrial DNA polymorphism

The first data are presented on mtDNA diversity in Besermyans, the Finno-Ugric ethnic group related to Udmurts. An analysis of mtDNA polymorphism showed that Besermyans stood out from the other populations of Volga-Ural region due to the presence of a large proportion of the Mongoloid component. The sample of Besermyans contained East Eurasian haplotypes not detected in ethnic populations of the Volga region and Cisurals, while they were detected in South Siberia, mostly among Turkic-speaking populations. An analysis of the genetic distances between Besermyans and the neighboring ethnic groups showed that Besermyans were distant from other populations of Volga-Ural region and close to Turkic-speaking populations of South Siberia. Thus, the data obtained favor the suggestion on the mixed Udmurto-Turkic origin of Besermyans.     

Antitumor activity of amides of dihydrobetulonic acid in vitro and in vivo

Amides containing homopiperidine and piperazine cycles were synthesized from dihydrobetulonic acid obtained by the oxidation of dihydrobetulin. All substances were shown to have a high antitumor activity (CCID₅₀ = 3.5–36.2 μM) in vitro in lymphoid (CEM-13, U-937) and monocytic (MT-4) human cell lines. Amides containing the methyl- and ethylpiperazine residues do not influence the viability of Lung Lewis Carcinoma cells in culture and do not have a significant effect on its transplants in C57BL/6 mice. However, these amides efficiently inhibit the development of metastases in lungs of these mice. The antimetastatic activity of the studied amides increases with changing the methyl by ethyl aliphatic residue in the piperazine cycle.     

Hepatoprotective activity of betulonic acid amides containing piperidine or pyrrolidine nitroxide moieties

Betulonic acid amides containing the nitroxyl radical moiety exert an anticholestatic effect in mice. The introduction of piperidine nitroxide moiety into the lupane core increases its hepatoprotective activity. Oral administration of the piperidine nitroxide derivative in a dose of 50 mg/kg does not stimulate transplanted tumor growth and increases lifespan in mice.     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Immunological and phenotypic characterization of cell constituents of breast milk

The morphology and immunological phenotype of plastic-adherent cells from human colostrum were studied in an in vitro short-term culture (6–7 days) using antibodies to CD3, CD31, CD34, CD45, CD68, vimentin, and osteocalcin. In 20% of the analyzed cultural flasks, nearly equal proportion of fibroblast-like cells and rounded cells was observed. In the 80% of the flasks, cells of regular shape were detected with the presence of single fibroblasts. The diameter of flattened cells ranged from 10 to 100 μm. All plastic-adherent cells did not express CD3 and showed weak binding (w) to the antibodies against CD31, CD34, and CD45. At the same time, we identified adherent cells that readily bound the antibodies against CD68, vimentin, and osteocalcin. According to the literature data, the CD68 + CD3^–CD31^wCD34^wCD45^w immunological phenotype of the majority of the adherent cells from the colostrum allows them to be classified as monocytes/macrophages. High expression of stromal antigens—vimentin and osteocalcin—in 40–45% of the adherent cells in the culturing medium lacking any osteogenic supplements (β-glycerophosphate, ascorbic acid, and dexamethason) implies the presence of osteoblasts in the colostrum, which differentiate from mesenchymal stem cells under the action of humoral factors contained in breast milk.     

Study of the filiform gonads of walleye pollock <Emphasis Type="Italic">Theragra chalcogramma</Emphasis> inhabiting the Sea of Okhotsk and the Bering Sea

The histological study of the adult specimens of walleye pollock Theragra chalcogramma carrying filamentous gonads evidenced that this group comprised males, females, and sterile fish. The specimens carrying the filamentous gonads have been found mostly in the elder age groups; no maturing of the oocytes or sperm cells has been registered. The frequency of occurrence of such specimens was relatively low: 0.07–0.13% in the Sea of Okhotsk and up to 0.25% in the Bering Sea. We conclude that these specimens have nearly no effect on the reproductive success of this species.