Genetic organization of transfer region of F-like plasmid pAP18-1

The results of complementation analysis of nitrosoguanidine-induced mutants of F-like drd-plasmid pAP18-1 (Tc, ColV) testified to the existence of at least 3 tra regions (tra1, tra2, tra3) and regulating locus fin V in the genome of this plasmid. By means of molecular cloning of tra2 region and locus fin V of plasmid pAP18-1drd were located in Sall-fragment f5 (3.9 MD).     

Differences between some properties of acetylated and nonacetylated forms of HMG1 protein

There are data suggesting that HMG1 protein may be involved in DNA replication. Recently we have found that only the acetylated form of the protein generates tetramers, stimulates the activity of DNA polymerase alpha (EC 2.7.7.7) (with activated DNA as a template) and forms a specific complex with it. This paper compares some properties of the acetylated and nonacetylated forms of HMG1 protein and shows that it is only the acetylated form which serves as a histone assembly factor, increases the melting temperature of poly d[(A-T)] and stimulates the activity of DNA polymerase alpha when histone H1-depleted chromatin is used as a template.     

Hyperbaric oxygenation in the comprehensive therapy of patients with rheumatoid arthritis (clinico-immunologic study)

For 35 of 50 patients with rheumatoid arthritis traditional drug therapy was a minor success for a long time. Without any modifications of the drug therapy every patient went through a course of hyperbaric oxygenation (HBO): 21 sessions under 1.7 ata for 40 min. Good clinical results both immediate and remote have been obtained. The effect of HBO on the immune system of the patients has intensified the suppressive function of T-lymphocytes (especially with systemic symptoms of the disease), normalized cell-bound immunity and decreased the serum concentration in immune complexes.     

Regulation of apolipoprotein expression]

Recent data and concepts on the structure and functioning of apolipoprotein genes as well as on the role of hereditary factors in pathogenesis of atherosclerosis are reviewed. The most important variants of inherited disorders in the system of apolipoproteins promoting the development of atherosclerosis are considered. Special attention is paid to the RFLP of apolipoprotein genes which serves as a peculiar genetic background, increasing probability of the atherosclerosis development in certain individuals.     

Turnover of cell surface-bound capsular polysaccharide in Staphylococcus aureus

The capsular polysaccharide (CPS) of Staphylococcus aureus strain Smith was labelled by growth of bacteria in the presence of radioactive N-acetylglucosamine and was separated from labelled cell wall components by affinity chromatography on wheat germ agglutinin following dissolution of the cells by lysostaphin. The products were partially characterised chemically and immunochemically. Similar labelled components were found in the culture fluid during growth. In a pulse-chase experiment, cell-bound CPS was released continuously into the culture fluid at the same rate as cell wall turnover and there was no evidence of direct excretion of CPS.     

Polydimethylsiloxane Films Modified with Chitosan/Pectin Multilayers as Scaffolds for Mesenchymal Stem Cells

Solid (smooth) and porous films of polydimethylsiloxane (PDMS) have been obtained; the effect of their structure on the adhesion of mesenchymal stem cells (MSCs) on their surface was found. It is shown that modification of these films with a (chitosan/pectin)₄ multilayer increased the efficiency of viable cell adhesion. A (3-aminopropyl)triethoxysilane–glutaraldehyde system was used to enhance the binding of the polysaccharide layer to the hydrophobic surface of PDMS. It was found that MSCs formed a monolayer culture of the fibroblast-like cells with high viability on porous PDMS modified with (chitosan/pectin)₄.     

Structure of vegetation of steppe hills in the Altai piedmont

The phytocenotic diversity of the Altai steppe piedmont is described. Plant communities were ordinated along the moisture gradient. The results were used to analyze the structure of vegetation of steppe hill massifs. Distribution of steppe vegetation over an ideal hill was simulated, and the main patterns of distribution were typified.