[EXPERIMENTAL AND THEORETICAL STUDIES OF HUMAN HYPERCAPNIC VENTILATORY RESPONSE WITH THE USE OF MATHEMATICAL GAS EXCHANGE MODELING].

A mathematical model of biotechnical system integrating the human cardiorespiratory system with hard- and software was designed to investigate breathing control. The model describes dynamics of carbon dioxide and oxygen in 3 biotechnical system compartments in the course of rebreathing tests. The tests do not require tanks with compressed gas and, therefore, can be performed in space flights.

[Dynamics of duration of tracheal forced expiratory noises during long-term isolation in the "Mars-500" experiment].

Dynamics of duration of tracheal forced expiratory noises in a group of volunteers was studied before, during and after 520-days confinement. The duration did not change in most volunteers. Two volunteers demonstrated significant changes of tracheal sounds duration and some spirometric parameters.

[Estimation of the forced expiration tracheal sounds intensity].

The investigation of tracheal sounds of forced expiration is realized on the basis of the mathematical model of forced expiration. It is demonstrated that a separation flow in the region of a dynamical contraction trachea during forced expiration may to cause tracheal sounds generation.

[Influence of changed gas media on acoustic parameters of human forced exhalation].

In previous study it was shown that duration of tracheal forced expiratory noises is promising to reveal negative changes of lung function after dive. The objective is a study of parameters of tracheal forced expiratory noises in changed gas media. The first experiment involved 25 volunteers (22-60 years), performed forced exhalation under normal pressure with air, oxygen-helium and oxygen-krypton mixtures.

[Characteristics of negative pressure inspiration effect on the cardiorespiratory system of humans in the conditions of 5-day dry immersion].

Changes in external respiration and central hemodynamics induced by negative (relative to atmospheric) inspiration pressure were studied in supine subjects before and on day-4 of a dry immersion (DI) experiment. Changes in the cardiorespiratory system as a result of negative inspiration pressure included rise of the amplitude of breathing motions and reduction of their frequency, and distinct breathing-related HR fluctuations. Combination of immersion and altered pressure in the mask caused breathing-related variations of systolic pressure and plethysmogram signal, and improved arterial blood oxygenation.

[Acoustic and spirometric indices of forced expiration noise in the conditions of 5-day dry immersion].

Dynamic studies of forced expiration (FE) indices involved 7 normal males aged 21 to 25 participating in a 5-d experiment with dry immersion (DI). FE spirometry was conducted simultaneously with registration of tracheal noise with the help of a microphone. Indices included acoustic duration of tracheal noise (Ta), forced lung capacity (FLC), FE volume per a second (FEV1), peak expiratory rate (PER) and time to reach (T(PER)) before DI, on DI days 1 and 4, and next day after completion.

[Biomechanics and regulation of the external respiration in the conditions of 5-day dry immersion].

The work was concerned with evaluation of the external respiration function and regulation in healthy human subjects participating in simulation of the microgravity effects by dry immersion (DI). In the baseline data collection period, in DI (days 2 and 4) and after DI completion pulmonary volumes were registered, the ratio of thoracic and abdominal components of quiet breathing and respiratory maneuvers calculated, and parameters of respiration regulation, i.e.

[Oxygen consumption by resting humans at different Elbrus altitudes].

The purpose of the work was to test experimentally the "hypoxic paradox" of growing or constant oxygen consumption by normal humans exposed to O2-deficient environments. The objective was to perform thorough statistical analysis of O2 consumption at two altitudes above sea level under the conditions of close to basic metabolism, and to develop an analytical expression for adequate description of O2 consumption dependence on altitude above seal level. The investigation was fulfilled in August, 2009 at the altitudes of 2224 and 4200 m on Elbrus flanks with participation of 4 volunteers.

[Investigation of the physiological effect of heated heliox on the human external respiration parameters].

The investigation was aimed at studying and comparison of the physiological effects of heated heliox and air on the human breathing function. Tests involved eight human subjects aged 24 +/- 4 who breathed gas mixtures and air heated to 58 +/- 5 degrees C for 21 minutes. Effects were evaluated by spontaneous pneometry and forced expiration using equipment Master Screen VIASYS.

[Application of minimally invasive lumbar sympathectomy in the treatment of patients with obliterating diseases of the lower extremity vessels].

The method of performance and immediate results of miniinvasive lumbar sympathectomy using retroperitoneal miniaccess were adduced in the work. In 2005 yr on the base of division of vascular surgery were operated 19 patients. Application of endoscopic instruments and optic system of illumination gave the possibility to remove lumbar sympathetic nodes in conditions of narrow (3-5 cm) surgical access and operative field.

[Antibiotic resistance of shigellae and rationale for etiotropic therapy of Shigella infections].

The study was aimed at determining sensitivity of shigellae to antibacterial preparations and their clinical effectiveness for correcting recommendations on the empirical therapy of acute Shigella infections (ASI). The sensitivity of 164 S. flexneri strains and 80 S.

[Clinical value of the use of magnesium orotate in adolescents with syndrome of cardiac connective tissue dysplasia].

According to results of clinical and instrumental investigation magnesium orotate (50 mg/day during first week and 25 mg/day thereafter) was found to be effective therapy of children with syndrome of cardiac connective tissue dysplasia (mainly with mitral valve prolapse and anomalous chordae tendineae).

[Characteristics of immune response in acute intestinal enterobacterial infections].

Update literature on the problem of microorganism--host interactions with pathogenic enterobacteria as a model is reviewed. The activation of lymphoid cells and their protective role is shown to be due to the stimulating action of bacterial antigens. The role of cytokines and stimulation of their expression are discussed.

[Diagnostic and epidemiological significance of F-donor activity of Enterobacteria strains].

The study of the circulating strains of enteropathogenic Escherichia coli (EPEC), shigellae and salmonellae for the presence of F-factor (the conjunction factor) was carried out. The study revealed that 85% of Shigella flexneri strains 2a had conjugative (F)-factor. The proportion of such strains was 63% among EPEC of different serovars and 15% among Salmonella enteritidis.

[The legal status of Russian HIV-infected persons].

According to the data, presented by the author and based on the study of opinions expressed by HIV-infected persons, 80% of them are subjected to discrimination. The article deals with the problem of the legal protection of HIV-infected persons in the Russian Federation. Additions and changes in the current legislation regarding foreign citizens and persons in places of confinement are proposed.

[Survival of laboratory animals in argon-containing hypoxic gaseous environments].

Present paper is aimed at assessing the effect of hypoxic gaseous mixtures intended for the use as the fire suppression agents within closed volumes on the basis of argon with addition of carbonic acid on the body of mammalia. Three experiments were performed on the male white laboratory Wistar rats. It is indicated that argon adding to the hypoxic mixtures containing 4-5% volume increases animal survivability as compared to analogous nitrogen-based mixtures.

[Preparation and characteristics of cultured strains of hepatitis A virus from humans and monkeys].

Cultural strains of hepatitis A virus (HAV) have been isolated from spontaneously infected Macaca mulatta (HAV-MM), Papio hamadryas (HAV-PH), African green monkeys Cercopithecus aethiops (HAV-CA), and patients (HAV-H). The strains replicate in continuous cells lines AGMK, 4647, Vero, and FRhk-4. AGMK and 4647 cells are the most permissive at 32 degrees C.