[Microbial fuel cells as an alternative power supply].

Purpose of the work was designing and prototyping of microbial fuel cells (MFC) and comparative evaluation of the electrogenic activity of wastewater autochthonous microorganisms as well as bacterial monocultures. Objects were model electrogenic strain Shewanella oneidensis MR-1, and an Ochrobactrum sp. strain isolated from the active anode biofilm of MFC composed as an electricity generating system. The study employed the methods typically used for aerobic and anaerobic strains, current measurement, identification of new electrogenic strains in microbial association of wastewater sludge and species definition by rRNA 16-S. As a result, two MFCs prototypes were tried out. Besides, it was shown that electrogenic activity of S. oneidensis MR-1 and Ochrobactrum sp. monocultures is similar but differs from that of the microbial association of the anode biofilm.

[Asymmetry of oxygenation and deoxygenation of a thick blood layer].

A cell for convoluted blood film was used to study the processes of oxygenation and deoxygenation in a 5-mm deep layer of whole blood contacting peripherally with a gas medium. It was shown that nitrogen replacement by oxygen or vice versa with steady 5% CO2 accelerates significantly blood oxygenation but not deoxygenation. On consideration of possible reasons a conclusion has been made in favor of geometric rather than physical-chemical factors. This phenomenon should be accounted for when encountering with stagnation state in organism, vascular occlusion and other circulation disorders.

[Probability of gravitational polarization of blood cells].

To study lucigenin-dependent chemiluminescence (ChL), samples of whole heparinized blood and isolated neutrophils of human blood were put in special cells between an indifferent wet dialysis membrane and a plate of solid material (polymer, metal or other) stimulating activation of polymorphonuclear leukocytes and monocytes. Production of ChL-registered O2 active forms depended on whether the stimulant was above or below cells. Search for possible artifacts made it clear that the trigger of the phenomenon is located inside cell or proximately. Some aspects of stimulation were amiss, i.e. independence from adhesive properties of the plate, role of erythrocytes, reversibility of the gravity-driven component in the sequence of processes leading to active oxygen production and others. However, the question as to whether it is cell or surrounding cell media that gets polarized by gravity is still an open question. This phenomenon may have implications for cell functioning in microgravity; under the 1 g conditions, it can facilitate understanding of cell reconstruction brought on by reorientation relative to the gravity vector.

[Role of the gravity vector in blood cell interaction with solid surface].

The gravity vector was shown to bear importance to the blood cell interaction with a foreign macroscopic solid surface. Contacting of human whole blood with the underside but not top side of a solid plate out of foreign material amplifies many times generation of active forms of oxygen. This observation may be testimony to gravitational polarization of intracell processes.

[Role of Mg2+ in keeping up the nonspecific immune functions of human neutrophils in vitro during hyperbaric exposure]. / Rol' Mg2+ v sokhranenii nespetsificheskikh immunnykh funktsii neitrofilov cheloveka in vitro v usloviiakh giperbarii.

Earlier we have shown inhibition of the production by neutrophils of active forms of oxygen in humans exposed to high pressure. To get better understanding of the role of Mg2+ in the process, magnitude of the effect was assessed as a function of Mg2+ concentration using the activated hemiluminescent technique. It appears that in vitro production of active oxygen forms by blood neutrophils at high pressures can be sustained provided increased concentrations of Mg2+ in the incubating medium.

[The effect of hyperbarism on the electrical stability and aggregation ability of liposomal membranes]. / Vliianie giperbarii na élektricheskuiu prochnost' i agregatsionnuiu sposobnost' membran liposom.

Helium pressure (100 bar) increases the electric breakdown potential of lipid bilayer by 4-5 mV and inhibits liposomal aggregation. These effects may result from the gain in surface tension of lipid/water interface, and the change in effective shape of lipid molecules. The studied effects may extenuate pressure effects on the synaptic junction.

[The effect of high pressure on induced lipid peroxidation processes in liposome membranes]. / Vliianie vyskogo davleniia na protsessy indutsirovannogo perekisnogo okisleniia lipidov v membrankh liposom.

The effect of high pressure on the Fe-ascorbate-induced lipid peroxidation in liposome suspensions has been studied. It was found that hydrostatic or helium pressure up to 140 bar increases the rate of MDA accumulation in this model system. This effect is assumed to be connected with the gain in polarity of the lipid bilayer under hyperbaric conditions.

[The effect of the pressure of metabolically inert gases and temperature on the membrane fluidity of liposomes]. / Vliianie davleniia metabolicheski inertnykh gazov i temperatury na tekuchest' membran liposomov.

The comparative analysis of pressure effects of helium, nitrogen (to 100 kg/cm2), cryptone (to 50 kg/cm2) and temperature (32-45 degrees C) on the lateral diffusion of pyrene in liposomal membranes of egg phospholipids was performed. The linear additivity of studied effects was demonstrated. The results are discussed from the point of view of the disturbances of cell processes in the hyperbaric conditions.