Sporadic increases of radioactive aerosols as a possible reason for heavy nuclides enhancements recorded with the en-detectors.

Some unexpected sporadic increases of an environmental radioactive background have been recorded at mountain level at Baksan Neutrino Observatory (BNO, 1700 m above sea level) using electron-neutron detectors (en-detectors), which could be explained by radioactive aerosol enhancements. The large area inorganic scintillator en-detectors developed for cosmic ray study are continuously monitoring environmental thermal neutron fluxes at various geophysical conditions. Application of the pulse shape discrimination method allows us to select and separately measure both thermal neutrons and radioactive beta-decay nuclides being products of radon decays in air (mostly Rn-222 and Rn-220). There are two en-detector setups running now at BNO, one deep underground while another one at surface. Both installations had recorded some strange sporadic increases of radioactive nuclides in air. In this paper, we present results and the most probable explanation of the significant increases joint by radioactive aerosols production but caused by different reasons: Baksan river floods or nearby underground experiment with powerful Cr-51 radioactive source.

Decrease of atmospheric neutron counts observed during thunderstorms.

We report here, in brief, some results of the observation and analysis of sporadic variations of atmospheric thermal neutron flux during thunderstorms. The results obtained with unshielded scintillation neutron detectors show a prominent flux decrease correlated with meteorological precipitations after a long dry period. No observations of neutron production during thunderstorms were reported during the three-year period of data recording.

[Bioimpedance means of skin condition monitoring during therapeutic and cosmetic procedures].

Engineering and technological problems of bioimpedance skin surface mapping are considered. A typical design of a device based on a PIC 16F microcontroller is suggested. It includes a keyboard, LCD indicator, probing current generator with programmed frequency tuning, and units for probing current monitoring and bioimpedance measurement. The electrode matrix of the device is constructed using nanotechnology. A microcontroller-controlled multiplexor provides scanning of interelectrode impedance, which makes it possible to obtain the impedance image of the skin surface under the electrode matrix. The microcontroller controls the probing signal generator frequency and allows layer-by-layer images of skin under the electrode matrix to be obtained. This makes it possible to use reconstruction tomography methods for analysis and monitoring of the skin condition during therapeutic and cosmetic procedures.

[Effects of actin cytoskeleton rearrangements on channel activation by calcium entry into A431 cells]. / Vliianie perestroek aktivnogo tsitoskeleta na aktivatsiiu kanalov kal'tsievogo vkhoda u kletok A431.

Using patch clamp and ion-selective fluorescence dye techniques, we investigated the influence of actin cytoskeleton rearrangements on the activity of calcium entry channels in plasma membrane of human carcinoma A431 cells. It is shown that disruption of actin microfilaments by cytohalasin D has no significant effect on calcium release from the stores and its entry from the extracellular space. It also does not interfere with the activation of inositol 1,4,5-trisphosphate (IP3)-dependent high-selective low-conductance calcium channels Imin. The treatment of cells with calyculin A induces the formation of actin filament layer beneath plasma membrane and also inhibits Imin activation and calcium entry through the plasma membrane, though calcium efflux from the stores was nearly unchanged. Thus, it is concluded that calcium signalling in A431 cells can be modulated by actin cytoskeleton rearrangements, and may be well described in terms of "conformational coupling" model.

Microbiological and epidemiological investigation of cholera epidemic in Ukraine during 1994 and 1995.

The Ukraine cholera epidemic of 1994 and 1995 was caused by Vibrio cholerae O1, serotype Ogawa, biotype El Tor. This epidemic was centred in the area around Respublika Krim (Crimea) and Mykolajiv, and spread to include parts of southern Ukraine. Cases of cholera occurred between September and November of 1994 and between June and October of 1995. The 32 fatalities among 1370 recorded cases (case fatality ratio, 2.3%) occurred throughout the course of the epidemic. V. cholerae from patients with cholera produced cholera toxin and were resistant to multiple antibiotics, though no resistance plasmids were found. Conjugation experiments suggested that resistance to multiple antibiotics may be present on a self-transmissible genetic element. Environmental sources of V. cholerae O1 El Tor included sewage, sea and surface water, and fresh water and marine fish. All but one of the environmental V. cholerae isolated during the epidemic were very similar to selected isolates from patients at the same time, supporting the role of these environmental sources in the spread of disease.

[The cellular fatty acid composition of bacteria in the family Vibrionaceae]. / Sostav kletochnykh zhirnykh kislot bakterii semeistva Vibrionaceae.

It is shown that strains of Vibrio cholerae of serovar O1, biovar eltor, subtype Ogawa, museum strains V. cholerae of serovar O1 and NAG-vibrios (isolated from various sources: sea, river and sewage water, canal water and people) possess identical composition of cell fatty acids with prevailing hexadecenoic, hexadecanoic and octadecenoic acids. Being identical, fatty acid profiles of V. parahaemolyticus and V. alginolyticus, are close to that of V. cholerae differing from the latter mainly by the higher content of dodecanoic acid. Similarity of Aeromonas sp. and Vibrio strains in the fatty acid composition proves phylogenetic relation-ship of these bacteria. Fatty acid composition of Plesiomonas shigelloides cells characterized by the presence of methylenhexadecanoic acid as well as by similarity with Vibrio and Aeromonas by the content of most fatty acids confirms a supposition of R. R. Colwell on the intermediate status of genus Plesiomonas between the families Enterobacteriaceae and Vibrionaceae. Independent of the growth medium, the strains Vibrio. Aeromonas and Plesiomonas preserved a fatty-acid profile, inherent in them, with variations mainly in the content of fatty acids with the odd number of carbon atoms. Allowing for relative stability of fatty acid composition and its peculiarity in certain taxonomic groups of the studied bacteria, the above test may be used as additional objective criterion to identify the representatives of Vibrionaceae family.

[The cellular fatty acid composition of bacteria in the family Vibrionaceae]. / Sostav kletochnykh zhirnykh kislot bakterii semeistva Vibrionaceae.

Vibrio cholerae strains, serovar O1, biovar eltor, subtype Ogawa, isolated from different sources, V. cholerae classica and NAG vibrios have identical cell fatty acid composition with the prevalence of hexadecenoic, hexadecanoic and octadecenoic acids. V. parahaemolyticus and V. alginolyticus fatty acid profiles, being identical, are similar to V. cholerae profile, differing from it mainly by a higher content of dodecanoic acid. The similarity of the fatty acid profiles of Aeromonas sp. and Vibrio strains is indicative of their phylogenetic relationship. The fatty acid composition of Plesiomonas shigelloides characterized by the presence of methylenehexadecanoic acid and at the same time by its similarity to that of Vibrio and Aeromonas in the content of the majority of fatty acids, confirms the position on the intermediate status of the genus Plesiomonas between the families Enterobacteriaceae and Vibrionaceae.

[Potential uses of plasma scalpel in liver and gallbladder surgery]. / Vozmozhnosti plazmennogo skalpelia pri operatsiiakh na pecheni i zhelchnom puzyre.

The article deals with the results of experimental studies and clinical experience in the use of the plasma scalpel in 25 unbred dogs and 192 patients with diseases of the liver and gallbladder. Histological studies of the hepatic tissue after treatment with the laser scalpel allowed the conclusion that such manipulations are safe. The advantages of using the device for arresting bleeding and the flow of bile from the resected hepatic areas were revealed. The accumulated experience in operations on the liver and gallbladder with a plasma scalpel made it possible to develop optimal approaches to the use of the plasma flow in resections of the liver and to suggest three methods for removal of the gallbladder. Their introduction into practice improved the intraoperative possibilities of treatment of the gallbladder bed.

[The characteristic properties of Vibrio cholerae eltor isolated from environmental objects on the territory of the former USSR during the 7th cholera pandemic]. / Kharakteristika nekotorykh svoistv Vibrio cholerae eltor, vydelennykh iz ob''ektov okruzhaiushchei sredy na territorii byvshego SSSR vo vremia sed'moi pandemii kholery.

The properties of 22,382 V. eltor strains isolated from environmental objects on the territory of different climatic and geographical zones during the period of 1970-1988 were studied. The study was made on the morphology of their colonies, the agglutinability of the strains by cholera O serum, type-specific serum and RO serum, their capacity for being lyzed by V. eltor bacteriophage, their hemolytic activity and virulence. Differences in the occurrence of strains with any of the above-mentioned properties, depending on the object from which they were isolate, the climatic and geographical zone and the intensity of the epidemiological situation with regard to cholera.

[Cholera in Ukraine and Moldova during the 7th pandemic]. / Kholera na Ukraine i v Moldove v period sed'moi pandemii.

The epidemic manifestations of cholera in the Ukraine and Moldova in 1970-1991 are analyzed. In the Ukraine the peak of cholera morbidity in 1970 was caused by infection brought to the ports of Odessa and Kerch with its subsequent spread to other territories. This infection was characterized by outbreaks transmitted through water, mainly sea water, with the isolation of Vibrio eltor toxigenic virulent strains and outbreaks of vibrio carriership of alimentary (dairy) origin with the isolation of avirulent strains. In Moldova local outbreaks of water origin were registered in 1970-1972. In both territories prolonged (up to 16 years and even longer) circulation of cholera vibrios, mainly nontoxigenic and avirulent, were registered. The retrospective epidemiological analysis and the epidemiological situation in some regions of the Ukraine in 1991 completely confirmed the prognostic importance of the division of territories into regions according to the type of epidemiological manifestations and the necessity of differentiating the measures to be taken in the system of epidemiological surveillance.

[The ecological and geographical aspects of the spread of Vibrio cholerae in environmental objects]. / Ekologo-geograficheskie aspekty rasprostraneniia Vibrio cholerae v ob''ektakh okruzhaiushchei sredy.

The results of studies carried out over the period of 24 years have revealed that V. eltor is widely spread in different ecological systems over a considerable part of the territory of the former USSR in the temperate and subtropical climatic zones. The duration and seasonal character of the isolation of these bacteria depend on climatic and geographical conditions, and their isolation rate greatly depends on the epidemic situation. The intensity and seasonal character of the isolation of V. eltor have been shown to depend on the character of the ecological system. For some water reservoirs definite biotic and abiotic factors capable of influencing the isolation rate of V. eltor have been determined, but no general regularities involving the above-mentioned factors and constantly ensuring such influence have been established.

[3 types of sperm proteins in eukaryotes]. / Tri tipa spermal'nykh belkov éukariot.

Basic spermal proteins of various species of hydrobionts attributed to Pisces and Cephalopoda are studied. It is established that chromatin of nine species referring to two Cypriniformes families includes the somatic histones. Histone H1 of Cypriniformes is attributed to the lysine-rich type histones and contains 35% mol. of lysine and 0.7% mol. of tyrosine. Chromatin of 14 species of fish referring to nine families of the percoid fish superorder includes protamines similar to salmin, a typical protamine of salmon. The amino acidic analysis of protamine from the sandre sperma has shown that it contains 59% mol. of arginine and no tyrosine. Chromatin of three species from squid superorder referring to Cephalopoda includes gametones -- proteins differing from histones and protamines both in the electrophoretic mobility and amino acidic composition (75% mol. of arginine, 3% mol. of tyrosine).