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Silver containing composites were prepared via diffusion/sorption of silver ions into previously synthesized functionalized poly(urethane-acrylate) matrices. I he peculiarities of coordination of Ag+ ions by carboxylate groups of the polymer chains followed by its reduction was observed by FTIR, UV-vis, SEM and lyophilicity measurements. Interactions between silver moieties and the functionalities of polymer matrices were identified by spectral studies. A high-temperature shift of relaxation transition temperature of PPO segments of silver-containing polymers in accordance with DMA studies is an additional evidence of coordination of different forms of silver (ions, clusters etc) by helix oligoether structures. I he conditions of sorption process as well as chemical structure of the matrices and reactivity of Ag+ ions provide a transformation of ionic silver into reduced metal moieties and its immobilization within surface layer of polymer matrices as nano- and submicron size aggregates. Nanoparticulate silver even in aggregated form demonstrates a strong surface plasmonic resonance with a maximum position depends on functionality of the matrix (mainly near 400 and 500 nm). [ABSTRACT FROM AUTHOR]

Polymer composite materials with antibacterial properties based on poly(vinyl alcohol), which contain fine biocompatible mineral fillers and silver nanoparticles have been obtained. The method of preparation of polyacrylamide stabilized silver nanoparticles with shape of thin truncated triangular prisms has been developed. An approach to enhance adsorption capacity of the fillers to nanoparticulate silver was proposed. Studying bactericidal activity of obtained materials on model microorganisms (Escherichia coli) shown the high activity of the composites containing silver nanoparticles at the concentration of ≥ 0,018 %. [ABSTRACT FROM AUTHOR]

Polyacrylate copolymers based porous polymer films were synthesized. Qualitative and quantitative analysis of electron microscopy images of the surface of obtained films were carried out. Dodecanol, cyclohexanol, low-molecular PEG, and their mixtures were shown to be effective porogens for porous materials production. [ABSTRACT FROM AUTHOR]

An ability of phosphate-mobilizing bacteria, related to four species of Bacillus genus, to colonize the cucumber root zone has been investigated. It has been found that all the studied strains can adapt to the root zone of those plants colonizing its parts to different extent. Essential nonuniformity of the root surface populating with bacteria is noted. Microcolonies of these organisms are formed in some root zones. This peculiarity is probably caused both by the difference in the number and composition of exudates of some zones of the plant roots, and by peculiarities of trophic requirements of the strains of studied bacteria The paper is presented in Ukrainian.

This study was devoted to the creation of biomagnetic sorbents, capable of removing the virus particles from the human blood serum. With this purpose specific globulins were isolated from reconvalescents sera after acute hepatitis B virus (HBV) and hepatitis C virus (HCV), which were later used as molecules-vectors (ligands). Ligands were covalently bound to magnetite encapsulated by the matrix, carrying aminopropyl groups on its surface. The dynamics of immunoglobulin sorption with magnet controllable bearer was studied. Sera which were positive by DNA HBV, by RNA HCVin polymerase-chain reaction (PCR) and by surface antigen HBsAg in immunosorbent assay (ELISA) were approbated with the purpose of virus separation by immunomagnetic sorbents. Completed virus decontamination of the serum was achieved according to results of PCR on DNA HBV, at the same time the results of ELISA testify to the presence of HBsAg in the tested samples of the serum, it can be associated with the presence of many defect virus particles in population or with the lack of biomagnetic sorbent for complete elimination. Results ofquality PCR on RNA HCV of sera after decontamination testify to the absence of complete HCV elimination.

Preparatory experiments for the IML-1 mission using plant protoplasts, were flown on a 14-day flight on Biokosmos 9 in September 1989. Thirty-six hours before launch of the biosatellite, protoplasts were isolated from hypocotyl cells of rapeseed (Brassica napus) and suspension cultures of carrot (Daucus carota). Ultrastructural and fluorescence analysis of cell aggregates from these protoplasts, cultured under microgravity conditions, have been performed. In the flight samples as well as in the ground controls, a portion of the total number of protoplasts regenerated cell walls. The processes of cell differentiation and proliferation under micro-g did not differ significantly from those under normal gravity conditions. However, in micro-g differences were observed in the ultrastructure of some organelles such as plastids and mitochondria. There was also an increase in the frequency of the occurrence of folds formed by the plasmalemma together with an increase in the degree of complexity of these folds. In cell cultures developed under micro-g conditions, the calcium content tends to decrease, compared to the ground control. Different aspects of using isolated protoplasts for clarifying the mechanisms of biological effects of microgravity are discussed.

Structural-functional organization of plasma membrane of pea roots seedling was investigated by methods of chemiluminescence, fluorescence probes, chromatography and freeze-fracture studies under normal conditions and clinostatting. Phase character of lipid peroxidation intensity was fixed. The initial phase of this process is characterized by lipid peroxidation decreasing with its next induction. The primary changes depending on free-radical mechanisms of lipid peroxidation were excellently revealed by chemiluminescence. Plasmalemma microviscosity increased on the average of 15-20% under microgravity at the initial stages of its phenomenon. There were major changes of phosphatidilcholine and phosphatidilethanolamine contents. The total quantity of phospholipids remained rather stable. Changes of phosphatide acid concentration point to degradation and phospholipids biosynthesis. There were increases of unsaturated fatty acids mainly at the expense of linoleic and linolenic acids and also a decrease of saturated fatty acid content at the expense of palmitic and stearic acids. Unsaturation index of fatty acids increased as well. On the whole fatty acid composition was variable in comparison with phospholipids. Probably it is one of mechanisms of maintaining of microviscosity within definite limits. Considerable structural changes in organization of plasmalemma protein-lipid complex were not revealed by the freeze-fracture studies.