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The spin-lattice relaxation of water protons in hydrosols of ultradispersed diamonds with the volume content of the dispersed phase up to 1% is studied by the high-resolution NMR. The relaxation rate of water protons is measured as a function of the dispersed phase concentration. It is shown that hydrosols of ultradispersed diamonds can be used as model systems for studying the relaxation parameters of aqueous phases in heterogeneous media. [ABSTRACT FROM AUTHOR]

The study of the action of the electromagnetic radiation (EMR) of low intensity (10 microW/cm2) in the range of frequencies 120-170 GHz at the test-reaction of Infusoria Paramecium caudatum was carried out. The resonant character of the effects was established. The EMR action at 156.6 and 161.3 GHz caused the increase of infusorians mobility, the action at frequencies 151.8, 155.7, 167.1 GHz caused the mobility reduction. Isolated and combined with EMR effects of nicotine (10(-4)-10(-15) mol/l) and antimicrobial drug metronidazole (10(-5), 10(-8), 10(-9) mol/l) were investigated. The radiation at the frequency 167.1 GHz was shown to reduce the effect of nicotine (10(-9) mol/l) and to enhance the effect of metronidazole (10(-9) mol/l). This phenomenon may be explained by different effects of the substances in low concentration at the water hydrogen bonds net structure.

Metronidazolum decreased diffusion mobility of membrane surface water. It is possible, that Wuks's effect represents the molecular mechanism underlying this phenomenon. We suppose, that protective action of the derivatives of the nitroimidazole on cell lysis is related to changes of the diffusion mobility of the surface water.

The effect of low morphine concentrations on the plasmatic membranes of erythrocytes without opiate receptors was investigated. It was shown that the ATPase activity and hemolytic stability of erythrocytes, which characterize the state of cell membranes and the mobility of the near-membrane water phase, depend on the concentration of morphine, and this dependence is wave-like. The nonmonotonous dependence of the biological response was suggested to be due to changes in the structure of water hydrogen links near the membrane surface, induced by opiate molecules. The hypothesis was confirmed by the results of studies of morphine water solutions using the methods of fluorescent probe and light scattering. It was found that the intensity of light scattering by water and the mobility of its molecules considerably increase in the presence of strictly specified concentrations of morphine.

The respiratory activity of Rhodococcus rhodochrous M8 cells containing nitrile hydratase and amidase was studied in the presence of nitriles and amides of carbonic acids. Culturing of cells with acrylonitrile and acrylamide yielding their maximum respiratory activity was studied. The optimum conditions for measurements and maintenance of respiratory activity were found. Curves for the linear concentration dependence of cell respiratory activity on 0.01-0.5 mM acrylonitrile, 0.025-1.0 mM acetonitrile, and 0.01-0.1 mM acrylamide were plotted. The selectivity of cell respiratory activity for some substrates was analyzed.

Nitrile hydratase was isolated and purified to homogeneity from cells of Rhodococcus rhodochrous M8. This enzyme catalyzes the hydrolysis of acrylic acid nitrile to acrylamide. Nitrile hydratase content in the cell was shown to be 17% of total soluble protein. The molecular weight of the native enzyme was 510 kDa. The enzyme consisted of two subunits with molecular weights of 23.5 kDa and 28.0 kDa. The N-terminal amino acid sequences of these subunits were estimated.

The influence of the water content, molar ratio, time and temperature on the formation of nondialysable melanoidins produced by the interaction of L-ascorbic acid and glycine has been studied. The isolated polymers have been characterized by spectrum analysis and fractionated using gel chromatography. The rate constants of the reaction for temperatures of 90 degrees C, 100 degrees C and 110 degrees C have been calculated and are (0.84 +/- 0.29) x 10(-5) x s-1, (1.33 +/- 0.14) x 10(-5) x s-1 and (5.30 +/- 0.37) x 10(-5) x s-1, respectively. The activation energy of the reaction has been determined to be 106.07 +/- 32.47 kJ/mol.