Phospholipids and cholesterol of liver nuclei during artificial hypobiosis of rats

The contents of lipids in the tissue and the nuclei of liver cells during artificial hypobiosis, as well as in the nuclei of liver cells for 3 days after the cessation of cooling in rats, were studied. In the artificial hypobiosis and in the state of normothermia 24 h after the cessation of cooling, the total phospholipid content of the liver cell nuclei increased by 20% due to minor phospholipids. The levels of sphingomyelin, phosphatidylinositol, phosphatidylserine, cardiolipin, and lysophosphatidylcholine were doubled in hypobiosis and then nonmonotonically returned to the normal level within 72 h. In the state of artificial hypobiosis, the levels of fatty acids, cholesterol, and diglycerides increased by 30–40%. The state of artificial hypobiosis did not affect the level of lipids in the liver tissue of Wistar rats. The increase of the lipid content in the liver cell nuclei of Wistar rats indicates the important role of lipids in functions of the nucleus when the energy supply and protein synthesis are inhibited under conditions of artificial hypobiosis.     

Enzymatic synthesis of dimeric glycomimetic ligands of NK cell activation receptors

This work reveals new structural relationships in the complex process of the interaction between activation receptors of natural killer cells (rat NKR-P1, human CD69) and novel bivalent carbohydrate glycomimetics. The length, glycosylation pattern and linker structure of receptor ligands were examined with respect to their ability to precipitate the receptor protein from solution, which simulates the in vivo process of receptor aggregation during NK cell activation. It was found that di-LacdiNAc triazole compounds show optimal performance, reaching up to 100% precipitation of the present protein receptors, and achieving high immunostimulatory activities without any tendency to trigger activation-induced apoptosis. In the synthesis of the compounds tested, two enzymatic approaches were applied. Whereas a β-N-acetylhexosaminidase could only glycosylate one of the two acceptor sites available with yields below 10%, the Y284L mutant of human placental β1,4-galactosyltransferase-1 worked as a perfect synthetic tool, accomplishing even quantitative glycosylation at both acceptor sites and with absolute regioselectivity for the C-4 position. This work insinuates new directions for further ligand structure optimisation and demonstrates the strong synthetic potential of the mutant human placental β1,4-galactosyltransferase-1 in the synthesis of multivalent glycomimetics and glycomaterials.     

Molecular genetic markers of intra- and interspecific divergence within starfish and sea urchins (Echinodermata)

A fragment of the mitochondrial COI gene from isolates of several echinoderm species was sequenced. The isolates were from three species of starfish from the Asteriidae family (Asterias amurensis and Aphelasterias japonica collected in the Sea of Japan and Asterias rubens collected in the White Sea) and from the sea urchin Echinocardium cordatum (family Loveniidae) collected in the Sea of Japan. Additionally, regions including internal transcribed spacers and 5.8S rRNA (ITS1–5.8S rDNA–ITS2) were sequenced for the three studied starfish species. Phylogenetic analysis of the obtained COI sequences together with earlier determined homologous COI sequences from Ast. forbesii, Ast. rubens, and Echinocardium laevigaster from the North Atlantic and E. cordatum from the Yellow and North Seas (GenBank) placed them into strictly conspecific clusters with high bootstrap support (99% in all cases). Only two exceptions–Ast. rubens DQ077915 sequence placed with the Ast. forbesii cluster and Aph. japonica DQ992560 sequence placed with the Ast. amurensis cluster–were likely results of species misidentification. The intraspecific polymorphism for the COI gene within the Asteriidae family varied within a range of 0.2-0.9% as estimated from the genetic distances. The corresponding intrageneric and intergeneric values were 10.4-12.1 and 21.8-29.8%, respectively. The interspecific divergence for the COI gene in the sea urchin of Echinocardium genus (family Loveniidae) was significantly higher (17.1-17.7%) than in the starfish, while intergeneric divergence (14.6-25.7%) was similar to that in asteroids. The interspecific genetic distances for the nuclear transcribed sequences (ITS1–5.8S rDNA–ITS2) within the Asteriidae family were lower (3.1-4.5%), and the intergeneric distances were significantly higher (32.8-35.0%), compared to the corresponding distances for the COI gene. These results suggest that the investigated molecular-genetic markers could be used for segregation and identification of echinoderm species.     

In vivo efficacy of Ingavirin against pandemic A (H1N1/09)v influenza virus

Ingavirin was shown to be efficient in inhibition of the pandemic influenza virus strains A/California/04/2009 (H1N1)v, A/California/07/2009 (H1N1)v, A/Moscow/225/2009 (H1N1)v and A/Moscow/226/2009 (H1N1)v. as well as the influenza virus strain A/Aichi/2/68 (H3N2) in the lungs of the infected mice. After oral administration of Ingavirin the titers of the influenza virus strains in the lung homogenates lowered.     

西伯利亚李斯特文卡遗址的大缺齿鼹化石

李斯特文卡(Лиственка)遗址位于俄罗斯西伯利亚叶尼塞河上游右岸的2级阶地,地理坐标为55°35′22″N,85°46′24″E。该遗址出土了丰富的细石器和骨器等文化遗存,是西伯利亚地区旧石器时代晚期重要文化遗址。遗址第7层距今时代约13.59-15.00 kaBP,从该层出土的哺乳动物化石中鉴定和研究了包括有3个个体的大缺齿鼹(Mogera robusta)化石材料。该批材料的发现,表明遗址古环境并不是以前人们认为的是处于冰缘森林-苔原和干草原-苔原环境,而应该是属于大陆性季风气候区,降水量比较充足且分布有泰加林和阔叶林组成的混交林地,具有软体动物、小哺乳动物、大哺乳动物等属种多样的良好生态环境。李斯特文卡遗址大缺齿鼹标本的研究,反映古人类在西伯利亚地区严寒而漫长的冬天里可能把捕捉大缺齿鼹作为重要的食物补充,为我们深入分析亚洲古人类文化交流、古人类体质进化及适应寒冷环境的生活方式等具有重要意义,对我们研究鼹科动物起源与演化等提供了重要研究素材。     

The role of IS-elements of Yersinia pestis (Lehmann, Neumann) in the emergence of calcium-independent mutations

Calcium independent mutants of two Yersinia pestis strains were studied. Insertions of IS100 element at three different sites of plasmid pCad within calcium dependence region were detected in Y. pestis EV, as well as two extensive deletions covering the whole region. It was shown that IS100 carries no HindIII sites. Novel IS element of Y. pestis designated IS101 was discovered in strain 358, in addition to IS100. It is distinguished by a slightly smaller size, HindIII site presence and high specificity of integration.