Investigation of erythrocyte shape, plasma membrane fluidity and conformation of haemoglobin haemoporphyrin under the influence of long-term space flight

The investigation of long-term space flight (SF) effect on the blood cells function is of great importance for modern space biology and medicine. We established that the number of discocytes decreased in the period of early rehabilitation after long-term SF. After SF plasma membrane fluidity and phospholipid content decreased and cholesterol content increased. After SF the amount of haemoglobin decreased and the parameters characterizing haemoglobin haemoporyphyrin (HH) conformation changed. We suppose that erythrocyte shape, membrane fluidity and HH conformation are among factors affecting oxygen transfer during and after space flight.     

Isolation and identification of Crimean-Congo hemorrhagic fever virus in the Stavropol territory

The results of the isolation and identification of the causative agent of a haemorrhagic fever outbreak in the Stavropol Territory are presented. The virus isolated from blood of haemorrhagic fever patients by virological methods was identified in serological and molecular tests as Crimean haemorrhagic fever virus. This epidemiological analysis testify to increased activity of the natural focus of Crimean-Congo haemorrhagic fever in this area due to a number of natural and other factors leading to intensification of its epidemic realization.     

Isolation and identification of the smallpox virus which caused iatrogenic vaccinia in children in the city of Vladivostok

The comparative study of the specimens of the morphological elements of exanthema obtained from 8 children with the clinical diagnosis of secondary exogenic vaccinia, dried smallpox vaccine and the cultures of other orthopoxviruses (rabbit pox, monkey pox and buffalo pox viruses) was made. The isolation and identification of the causative agents from the specimens was carried out with the use of modern virological, electron microscopic and molecular methods. The study proved the fact that 8 children had orthopoxvirus infection with its causative agent identified as vaccinia virus.     

Influence of nerve fiber K+ depolarization and altered membrane protein conformation on the state of myelin

Using Raman spectrometry and fluorescence microscopy, we studied the rearrangement of carotenoid molecules and membrane-bound Ca _mb ²⁺ in myelinated nerve fibers after K⁺ depolarization, K⁺-channel blocking, and altering the membrane protein conformation. We observed a decrease in Ca _mb ²⁺ and an increase of microviscosity in myelin after depolarization. Changes in Ca _mb ²⁺ and microviscosity were registered after blocking the K⁺ channels and modifying proteins with PCMB. Our results suggest an interconnection between the condition of nerve fiber membrane proteins, Ca _mb ²⁺ distribution, and myelin microviscosity.     

Orientational Ordering of Carotenoids in Myelin Membranes Resolved by Polarized Raman Microspectroscopy

We study orientational ordering of membrane compounds in the myelinated nerve fiber by means of polarized Raman microspectroscopy. The theory of orientational distribution functions was adapted to live-cell measurements. The obtained orientational distribution functions of carotenoids and lipid acyl chain clearly indicated a predominantly radial-like orientation in membranes of the myelin. Two-dimensional Raman images, made under optimal polarization of incident laser beam, corroborated the proposed carotenoid orientation within the bilayer. Experimental data suggested the tilted orientation of both carotenoid polyenic and lipid acyl chains. The values of maximum tilt angles were similar, with possible implication of carotenoid-induced ordering effect on lipid acyl chains, and hence change of myelin membrane properties. This study stages carotenoids of the nerve as possible mediators of excitation and leverages underlying activity-dependent membrane reordering.     

Effect of chitooligosaccharides on peroxidase isoenzyme composition in wheat calli cocultured with bunt causal agent

Effects of chitooligosaccharides (COS) on the activity of peroxidase and its isoenzyme composition were investigated in cocultures of wheat calli (Triticum aestivum L.) with common bunt fungal pathogen (Tilletia caries (DC) Tul.). COS elevated the activity of readily soluble form of peroxidase: at concentrations of 0.01 and 1 mg/l, peroxidases with isoelectric points (pI) of about 3.5 and 9.8 and at concentration of 100 mg/l—those with pI of 4.3–5.2 were activated. It was shown that treatment with COS boosted the resistance of wheat calli to T. caries, inducing the accumulation in the cell wall of pathogen-specific isoperoxidases, especially its anionic isoform with pI ∼ 3.5. The ultimate indicator of defense responses is quick lignification of cultured cell walls under the effect of COS in the contamination area.     

Studies of diversity of benthic fauna of lakes in Mari El Republic by rank distribution method in perspectives of application to water quality biological benchmark

The dataset on benthic fauna diversity obtained by ecological monitoring of lakes (Mari El Republic) was analyzed for applicability in water quality biological benchmark. The effect of several parameters on biodiversity were tested: (1) calculation errors in species number definition, (2) application of certain evaluation method of rank distribution parameters, (3) adequacy degree of distribution model, (4) evenness: diversity ratio, (5) hydrochemical parameters of lake, and (6) “sampling site effect” (natural reserve area impact). The biodiversity characteristics were suggested, which highly correlated to obtained data. The critical level for each characteristic was proposed to define favorable and adverse conditions of benthic communities. Practical recommendations were given for using studied parameters in the evaluation of the water quality biological benchmark in Mari El Republic.     

A study of the catalytic properties of the nitrile hydratase immobilized on aluminum oxides and carbon-containing adsorbents

The nitrile hydratase isolated from Rhodococcus ruber strain gt1, displaying a high nitrile hydratase activity, was immobilized on unmodified aluminum oxides and carbon-containing adsorbents, including the carbon support Sibunit. The activity and operational stability of the immobilized nitrile hydratase were studied in the reaction of acrylonitrile transformation into acrylamide. It was demonstrated that an increase in the carbon content in the support led to an increase in the amount of adsorbed enzyme and, concurrently, to a decrease in its activity. The nitrile hydratase immobilized on Sibunit and carbon-containing aluminum α-oxide having a “crust” structure displayed the highest operational stability in acrylonitrile hydration. It was shown that the thermostability of adsorbed nitrile hydratase increased by one order of magnitude.