Haplotype of Y-chromosomes in the Central Asia population

The distribution of alleles and haplotypes of three diallellic Y-specific loci (YAP, DYF155S2, and Tat) in the populations of Kyrgyz, Uzbeks and Tajiks was analyzed. In Kyrgyzes and Uzbeks, a relatively high frequency of the DYF155S2 deletion (20 and 12.5%, respectively) and the C allele at the Tat locus (11.2 and 8.3%, respectively) were revealed. In the populations of southern Kyrgyzes and Uzbeks, two chromosomes carrying the YAP+ allele were detected. In both cases the YAP+ allele was found within the YAP+/DYF155S2+/TatT haplotype. The Tajik population was monomorphic in respect to the polymorphisms studied. The Tajiks demonstrated the presence of only the YAP-/DYF155S2+/TatT haplotype. This haplotype appeared to be most frequent in Kyrgyz (78.8%) and Uzbeks (83.3%). The question on the origin and the distribution of Y-chromosome variants in Eurasia are discussed.     

Epidemiological surveillance on natural-borne infections in the Ulyanovsk region

The analysis of natural foci of haemorrhagic fever with renal syndrome (HFRS) and tick-borne borreliosis on the territory of the Ulyanovsk region is presented. Reduced rat control interventions result in a wide spread of these and other infections with natural focality. Monitoring of natural foci of HFRS, tick-borne borreliosis and arbovirus infections, their typing and determination of main reservoirs are the most promising among epidemiological surveillance methods.     

The accumulation and degradation dynamics of cyanophycin in cyanobacteria grown in symbiotic associations with plant tissues and cells

Five different artificial associations of cyanobacterial cells with the cells or tissues of nightshade and rauwolfia were studied. The associations grown on nitrogen-containing media produced heterocysts. Cyanobacterial cells in the associations retained their ability to take up bound nitrogen from the medium, to store it in the form of cyanophycin granules, and to use them in the process of symbiotic growth. The synthesis and degradation of cyanophycin granules in cyanobacterial cells were more active in the associations than in monocultures. In the symbiotic associations of Chlorogloeopsis fritschii ATCC 27193 with Solanum laciniatum cells and of Nostoc muscorum CALU 304 with the Rauwolfia serpentina callus, heterocysts were produced at 3- to 30-fold higher cyanophycin contents than in cyanobacterial monocultures. In contrast, in the association of N. muscorum CALU 304 with the Solanum dulcamara callus, heterocysts were produced at lower cyanophycin contents than in the N. muscorum CALU 304 monoculture. The degradation of cyanophycin granules in N. muscorum CALU 304 cells grown in associations with plant tissues or cells was subjected to mathematical analysis. The activation of cyanophycin degradation and heterocyst production in the associations N. muscorum CALU 304-R. serpentina and C. fritschii-S. laciniatum was accompanied by an enhanced synthesis of the nitrogen-containing alkaloids in plant cells. The data obtained suggest that an integrated system of nitrogen homeostasis can be formed in symbiotic associations. Depending on the growth stage of an association, its plant member can either stimulate the accumulation of bound nitrogen in vegetative cyanobacterial cells in the form of cyanophycin granules, or activate their degradation, or initiate the formation of heterocysts independently of the cyanobacterial sensory-signalling system.     

Urokinase induces adhesion of monocytes to fibrinogen

Urokinase activates adhesion of monocytic U937 cells to fibrinogen-coated surface. This effect is due to urokinase proteolytic activity and does not depend on the urokinase binding to its receptor.     

Single amino acid substitutions in the Ca2+-binding site of recoverin.II.The unusual behavior of the protein upon the binding of calcium ions

The structural properties of myristoylated forms of recombinant recoverin of the wild type and of its mutants with damaged second and/or third Ca(2+)-binding sites were studied by fluorimetry and circular dichroism. The interaction of wild-type recoverin with calcium ions was shown to induce unusual structural rearrangements in its molecule. In particular, protein binding with Ca2+ ions results in an increase in the mobility of the environment of Trp residues, in higher hydrophobicity, and in elevated thermal stability (its thermal transition shifts by 15 degrees C to higher temperatures) but has almost no effect on its secondary structure. Similar structural changes induced by Ca2+ are also characteristic of the -EF2 mutant of recoverin whose second Ca(2+)-binding site is modified and cannot bind calcium ions. The structural properties of the -EF3 and -EF2,3 mutants (whose third or simultaneously second and third Ca(2+)-binding sites, respectively, are modified and damaged) are practically indifferent to calcium ions.     

On prediction of folding nuclei in globular proteins

The approach described in this paper on the prediction of folding nuclei in globular proteins with known three dimensional structures is based on a search of the lowest saddle points through the barrier separating the unfolded state from the native structure on the free-energy landscape of protein chain. This search is performed by a dynamic programming method. Comparison of theoretical results with experimental data on the folding nuclei of two dozen of proteins shows that our model provides good phi value predictions for proteins whose structures have been determined by X-ray analysis, with a less limited success for proteins whose structures have been determined by NMR techniques only. Consideration of a full ensemble of transition states results in more successful prediction than consideration of only the transition states with the minimal free energy. In conclusion we have predicted the localization of folding nuclei for three dimensional protein structures for which kinetics of folding is studied now but the localization of folding nuclei is still unknown.     

The influence of mesenchymal stem cells on bone tissue regeneration upon implantation of demineralized bone matrix

Mesenchymal stem cells (MSC) are resident pluripotent cells of bone marrow stroma. MSC are able to differentiate into chondroblasts, adipocytes, neurons, glia, cardiomyocytes, or osteoblasts. The problem of MSC usage in cell therapy of bone defects is widely discussed at present. The experiments were carried out using rats of inbred line Wistar-Kyoto. MSC were isolated from bone marrow and cultivated in vitro. Demineralized bone matrices (DBM) were obtained from parietal bones of rats and hens. Part of DBM was loaded with MSC. Bone defects were made in cranium parietal regions. DBM with or without MSC or metal plates were transplanted in these regions. It was shown that the application of MSC increased angiogenesis and osteogenesis in the damaged bone. The implantation of rat's DBM with MSC led to the formation of a full value bone. MSC suppressed inflammation, when transplantation of hen's DBM was carried out. The application of MSC always improved bone tissue regeneration.     

Genetic divergence of sympatric charrs of the genus Salvelinus from Nachikinskoe Lake (Kamchatka)

We studied genetic differentiation of two charr species, Dolly Varden Salvelinus malma malma Walbaum and resident lacustrine charr Salvelinus sp., which sympatrically inhabit Nachikinskoe Lake (the Bol'shaya River basin) in southwestern Kamchatka Peninsula. Using restriction analysis (RFLP), three mitochondrial DNA fragments (ND1/ND2, ND5/ND6, and Cytb/D loop) amplified in polymerase chain reaction (PCR) were compared. The divergence of the mtDNA sequences between Salvelinus sp. and S. malma malma was 2.8%; Salvelinus sp. and S. taranetzi, 0.36%; Salvelinus sp. and S. krogiusae, 0.21%; Salvelinus sp. and S. alpinus, 3.0%. These results point to reproductive isolation of charrs in Nachikinskoe Lake and support the earlier suggestion on a close relationship between Salvelinus sp., S. taranetzi, and S. krogiusae.     

Influence of intracellular pH on character of mice peritoneal macrophage response to red light irradiation

It was detected that exposure of macrophages to red light (600-740 nm) led to the changes in their intracellular pH and hydrolytic activity. The character of these changes depends on the initial level of pH in the cells. The maximum effect of irradiation is detected if the initial pH level is low. It is possible that Na/H-exchanger takes part in normalizing effect of red light on intracellular pH level.     

Mathematical modeling of electron and protein transport, coupled with ATP synthesis in chloroplasts

A mathematical model of electron and proton transport in chloroplasts of higher plants was developed, which takes into account the lateral heterogeneity of the lamellar system. Based on the results of numerical experiments, lateral profiles of pH in the thylakoid lumen and in the narrow gap between grana thylakoids under different metabolic conditions (in the state of photosynthetic control and under photophosphorylation conditions) were simulated. Lateral profiles of pH in the thylakoid lumen and in the intrathylakoid gap were simulated for different values of the proton diffusion coefficient and stroma pH. The model demonstrated that there might be two mechanisms of regulation of electron and proton transport in chloroplasts: (1) the slowing down of noncyclic electron transport due to a decrease in the intrathylakoid pH, and (2) the retardation of plastoquinone reduction due to slow diffusion of protons inside the narrow gap between the thylakoids of grana.