[Study of surface-active properties antivirials compound 1-boraadamantane for model monomoleculars phosphlipids layers].

The surface-active properties of 1-boraadamantane have been studied using model phospholipid monolayers. Results suggest that the increase in 1-boraadamantane concentrations from 10(-7) to 10(-6) M is accompanied by the increase of the area per phospholipid molecule. This decreases to frequency of lateral diffusion of phospholipids molecules, the potential difference and the angle of the phospholipid monolayer arrangement. These phenomena may lead to impossibility of interaction between the virus and cell membranes.

[The study of structural changes in influenza virus hemagglutinin (HA) after interaction with liposomes by the fluorescence method].

Using the method of self fluorescence quenching influence of phospholipids on conformational state of HA has been studied. Interactions of HA with model phospholipids membranes are accompanied by changes of structure-dynamic protein organization. This method could be used for controlling the structure organization of proteins after receiving by virus the influenzal virusomal vaccine.

[Influence of polyelectrolytes on measles virus infectivity].

AIM: Mechanism of virus inhibiting action against measles virus of polyelectrolytes (PE) polystyrolsulfonate (PSS) of various polymerization degree and 60 kDa molecular weight polyallylamine (PAA) was studied. MATERIALS AND METHODS: Measles virus Leningrad-16 strain was used for the study. Virus infectious titer reduction kinetics after interaction with PSS with the degree of polymerization of 8 (PSS 8), 31, 77, 170, 360, 430 and PAA were determined by titration method with cytopathogenic effect detection in Vero continuous cell line. Circular dichroism and fluorescence spectra of viral proteins were obtained by using Zenith 200st spectrophotometer (Russian Federation) and Jasco J-810 dichrograph (Japan). RESULTS: A significant decrease of measles virus infectious titers after interaction with PSS with the degree of polymerization of 8 and PAA in concentration of 30 mM was detected. Analysis of circular dichroism spectra and protein fluorescence allowed to determine the mechanism of interaction of the indicated PE with measles virus surface proteins. The secondary structure of viral proteins is damaged by hydrophobic polar frame of these PE, polyanion PSS 8 also interacts with positive charges of protein groups that leads to the formation of loops and tails that disrupt alpha-spirals. CONCLUSION: The studied PE could be considered as potential antiviral preparations, and methods of circular dichroism and protein fluorescence could be used to detect damage of viral protein secondary structure by agents of different kinds.

[New method for measurement of size and concentration of lyposomes].

AIM: To develop new method of determination of size and concentration of lyposomes based on measurement of opacity in dispersed media. MATERIALS AND METHODS: Dispersions of lyposomes from dipalmitoylposphatidylcholine were the object of the study. Opacity spectrum of lyposome suspension was measured with Zenyth 200st spectrophotometer. Mean values of diameter of lyposomes determined by opacity spectrum were compared with the same values measured by electron microscopy (JEM 100-CX, JEOL, Japan) with magnification 58,000 - 100,000. Refraction index was measured with refractometer RPL-3 (Russia). RESULTS: Sizes of lyposomes measured by the new method and by electron microscopy did not differ significantly. Determination of sizes and concentration of lyposomes by the new method did not depend from effect of secondary multiple scattering of light. CONCLUSION: Obtained data allowed to conclude that developed method could be used in practice. Advantages of the new method are usage of common spectrophotometers and photoelectrocolorimeters for deriving of liposomes suspension opacity curve as well as its high validity, which are confirmed by data obtained with electron microscopy.