[Etiology of fatal pneumonia caused by influenza A(H1N1)pdm2009 virus during the pandemic in Russia].

The results of the study of the autopsy materials from 61 patients with the diagnosis of pneumonia received by virological and genetic methods are reviewed. The materials were studied at the Influenza Etiology and Epidemiology Center of the Ivanovsky Institute of Virology, Ministry of Health and Social Development of the Russian Federation, during epidemic seasons 2009-2010 and 2010-2011. The data were analyzed with respect to age, sex, comorbidity diseases and identified on the groups of the risk of severe forms of the disease. The presence of the pandemic influenza virus strain RNA was confirmed in 70.5% of materials; RNA of influenza B was detected in 1.2% cases. The co-infections caused by the bocavirus, adenovirus, parainfluenza virus type 2 and 4, rhinovirus, and streptococcus were detected only in 19.7%. In most cases, the influenza virus was the etiologic agent of lethal pneumonia, which justifies the necessity of the early etiological diagnosis and treatment with antiviral drugs.

New functions of small nucleolar RNAs.

Small nucleolar RNAs (snoRNAs) are one of the most abundant and well-studied groups of non-coding RNAs. snoRNAs are mostly engaged in processing of rRNA. However, recent data indicate that snoRNAs are also involved in other processes including regulation of alternative splicing, translation and oxidative stress. snoRNAs are also involved in pathogenesis of some hereditary diseases and cancer. Therefore, the range of snoRNAs' functions is significantly wider than it has been assumed earlier.

[Adaptation processes in mice during chronic combined exposure to radiation and chemical compounds (acetone, ethanol, acetaldehyde) innate to exploration missions].

The paper reports the results of experimental investigation with mice subjected to 63-day of daily 10-fold fractionated gamma-irradiation at the total dose of 350 cGy followed by 70-day exposure to chemical mixture (acetone, ethanol, acetate aldehyde) at close to maximum permissible concentrations innate to piloted space vehicles (MPCpsv). Measured levels of radiation and known radiation sensitivity of mice were used to model absorbed dose to cosmonauts on an exploration mission. Functional shifts in the hematopoietic system and changes in biochemical parameters of erythrocytes indicative of energy exchange and redox potential were tracked up during the combined radiation-chemical exposure and 90 days of recovery. It was shown that adaptation caused pronounced and strongly pronounced tension of regulatory mechanisms, particularly under the effects of radiation. High tension still persisted in the recovery period.

[Studies of red blood cells biochemistry and erythropoiesis intensity in humans during the 520-day isolation study].

Erythrocyte metabolism and erythropoiesis intensity were investigated in the humans subjects (6 males, 25 to 37 yrs. of age) volunteered for experimental simulation of such factors in a mission to Mars as very long duration (520-d) of isolation and confinement, autonomy, delayed communication, emergencies, and limited consumable resources. Venous blood and extracted erythrocytes were analyzed in the baseline data collection period (2 wks. before the experiment), on days 60, 120, 170, 240, 300, 360, 417 and 510 of the experiment and on days 7-8 after its completion. Erythrocyte metabolic and plasmatic membrane parameters were measured. Blood serum was analyzed for iron turnover; erythropoiesis intensity was evaluated by the erythropoietin level. According to the results of the investigation, there were phase-type shifts in the parameters throughout the experiment that were particularly significant on days 60 and 120. Inhibition of energy-production and enhancement of reparative processes in the cell could be tokens of compensatory reactions aimed to control oxidation processes and to raise antioxidation efficiency of the cell. The phase-type changes in membrane lipids and phospholipids point to increased microviscosity of the plasmatic membrane at the beginning and then end of the experiment. Hemoglobin content in blood and erythrocytes showed a significant increase on day-510 of isolation and in the ensuing recovery period. Data about iron turnover and erythropoietin level evidence an adequate bone marrow response to the changed hemoglobin content in blood.

[Radiation lesion formation and character of repair processes in the hematopoietic system of primates exposed to continuous and fractionated gamma-irradiation by equally effective doses].

The article is dedicated to comparison of the biological effectiveness of continuous and fractionated gamma-irradiation of rhesus macaques by equally effective doses. These radiation conditions are broadly used in radiobiological experiments. Specifically, they are applied in modeling radiation effects on cosmonauts during extended exploration mission. A model of radiation damage and repair on the cell, tissue and organism levels, i.e., a model of effective residual dose responsible for change in mammals' resistance to irradiation of varying duration was used to calculate equally effective doses in the experiment with primates subject to continuous and fractionated exposure. The authors publish data related to formation of radiation lesion and rate of ensuing hemopoiesis reparation. Two groups of animals were compared in resistance modification followed after testing by acute irradiation. The test was to reproduce a radiation situation for cosmonauts in the event of a cannonade of powerful solar proton events resulting in an effective residual dose of 1 Sv total The experiment evidenced close resemblance of the hemopoietic effects in primates exposed to the compared radiation conditions.

[Reasons of low epizootic activity of natural foci of plague in Russia at the beginning of the 21st century].

AIM: Establish the main reasons of low epizootic activity of natural foci of plague in Russian Federation in 2000-2009. MATERIALS AND METHODS: Multiyear data on the number of isolated Yersinia pestis strains, area of detected epizootic sites, amounts of the field material studied for plague were used to evaluate annual activity of natural foci. RESULTS: In the current decade mountain and high-mountain natural foci of plague were characterized by constant high epizootic activity. In plains and low-mountain natural foci a low periodic epizootic activity was noticed, a development of intra-epizootic periods. A conditioning role of helioclimatic factors on the status of parasitic systems and epizootic activity of natural foci of plague was noticed. CONCLUSION: The warming of climate in 1990-2007 was the main reason for low epizootic activity of plains natural foci of plague in Russia. In the contemporary conditions of a recurrent cooling (from 2008) and an increase of humidity in the Northern, North-Western pre-Caspian and pre-Caucasus territories, a new significant activation of them is predicted there with a peak in 2017-2019.

[Studies of the blood antioxidant system and oxygen-transporting properties of human erythrocytes during 105-day isolation].

Effects of strict 105-d isolation on blood antioxidant status, erythrocyte membrane processes and oxygen-binding properties of hemoglobin were studied in 6 male volunteers (25 to 40 y.o.) in ground-based simulation of a mission to Mars (experiment Mars-105). The parameters were measured using venous blood samples collected during BDC, on days 35, 70 and 105 of the experiment and on days 7 and 14-15 after its completion. Methods of biochemistry (determination of enzyme activity and thin-layer chromatography) and biophysical (laser interference microscopy, Raman spectroscopy) showed changes in relative content of lipid and phospholipid fractions suggesting growth of membrane microviscosity and increase in TBA-AP (active products of lipids peroxidation interacting with thiobarbituric acid). A significant increase in glucose-6-phosphate dehydrogenase and superoxide dismutase activities against reduction of catalase activity points to both reparative processes in erythrocytes and disbalance between the number of evolving active forms of oxygen and antioxidant protection mechanisms in cells. Hemoglobin sensitivity of oxygen and blood level of oxyhemoglobin were found to increase, too. It is presumed that adaptation of organism to stresses experienced during and after the experiment may destroy balance of the antioxidant protection systems which is conducive to oxidation of membrane phospholipids, alteration of their content, increase of membrane microviscosity and eventual failure of the gas-exchange function of erythrocytes.

[Examination of the morphofunctional properties of red blood cells of humans in 5-day dry immersioin].

Blood of six normal male volunteers sampled before, immediately after and in 7 days since 5-d dry immersion was analyzed for morphological parameters, erythrocyte metabolism, lipids and phospholipids levels. The experimental exposure was shown to increase the erythrocyte count. Also, upward trends were displayed by hemoglobin and PCV on the first day after the experiment; a significant decrease in adenosine triphosphate and low level of reduced glutathione could be an outcome of enhanced oxidation in cell due to, maybe, LPO activation. There was a downward trend in the phospholipids fraction of erythrocyte membrane against steady levels of cholesterol and its ethers which might be linked with the reliable growth of the fraction of nonesterified fatty acids on day 1 and triglycerides on days 1 and 7 post the experiment.

[Investigation of the morphofunctional properties of human red blood cells under the conditions of 7-day dry immersion].

Morphobiochemistry of erythrocytes, erythropoiesis intensity (determined by iron metabolism and erythropoietin content), lipids and phospholipids of erythrocyte plasmatic membrane and oxygen binding and release by hemoglobin were studied in normal male volunteers for 7-d dry immersion. Investigations were performed before the experiment, on the last day in immersion (d-7) and on days 7 and 15 of recovery. After 7-d dry immersion, the volunteers exhibited a trend towards changes in red blood morphology, erythropoiesis intensity, and erythrocyte metabolism. Seven-day simulation of microgravity alters significantly the oxygen-transporting function of erythrocytes. This is, probably, associated with shifts in the cell membrane evidenced by apparent changes in phospholipids fractions. These changes have no clinical significance as concluded from reestablishment of most of the parameters by day 15 of recovery. The broad variability of measured values is attributed to individual character of body response to the stresses of the experiment.

[Investigations of the morphofunctional properties of red blood in human subjects during 9-day exposure in oxyargon medium with various oxygen content].

Biochemical investigations of red blood and oxygen transportation by erythrocyte hemoglobin were performed in volunteered for chamber experiments (0.14 MPa) with normal and hypoxic oxyargon medium (O2-Ar). Erythrocyte metabolism, lipid and phospholipids spectra, and effectiveness of oxygen release and retention by hemoglobin were studied in the baseline data collection period, on day 6 in hyperbaric and normoxic O2-Ar medium (13.7% O2), on day 3 in hyperbaric and hypoxic O2-Ar (9.9% O2) and on day 1 and 10 during the post-experiment rehab. Elevated pressure, hypoxia and ensuing decompression revealed an ATP reduction that could be a result of shifts on the membrane level and increased G6PD activity associated with cell reparation processes. Changes in membrane lipid and phospholipids composition point to an altered phase state of plasmatic membrane, i.e., increased viscosity which is indicative of possible impairment of membrane permeability As a rule, hyperbaria impacted oxygen transportation in blood of the subjects; effect of hypoxia combined with hyperbaria was not uniform ranging from none to decreasing or increasing oxygen transportation that can be extenuated by selectivity and individual sensitivity to the factors in the experiment Loss of O2 transportation efficiency by hemoglobin is most likely connected with the increase of plasmatic membrane viscosity that could affect hemoporphyrin conformation of membrane-bound hemoglobin and obstruct oxygen transport though membrane.

[Vibrio cholerae serogroups O1 and O139: susceptibility to antibiotics during 7th cholera pandemic].

The review presents data on circulation of antibiotic resistant and susceptible strains of Vibrio cholerae serogroups O1 and O139 isolated from cholera patients and healthy persons as well as from the environment, in Asia, Africa, Australia, and Europe (including New Independent States) during 7th cholera pandemic.

[Role of viscosity and permeability of erythrocyte plasmatic membrane in controlling the oxygen transport effectiveness by human hemoglobin on completion of space flight].

Plasmatic membrane viscosity and permeability and hemoporphyrine conformation in human hemoglobin were studied on completion of long-duration space flight (LSF). Reversible increases in viscosity and selective permeability (Na+/H+ -turnover) of erythrocyte plasmatic membrane were observed immediately after and in the period of recovery from LSF. Viscosity of lipids in both external and internal locations of plasmatic membrane in human erythrocytes was changed after LSF. The reversible rise of the Na+/H+ -turnover is likely to alter intracellular pH and oxygen binding with hemoglobin. The former is confirmed by the concurrent reversible decline in the deoxyhemoglobin ability to bind oxygen and the oxyhemoglobin ability to retain oxygen. In LSF and during readaptation to the normal gravity blood levels of hemoglobin and free iron are known to be reduced and may be answerable for the hypoxic state of human organism.

[Cytogenetic and biochemical reactions of experimental animals to combined exposure to low-intensity radiation and chemical factors].

Combined exposure of mice to a mixture of chemicals in small quantities and gamma-radiation at a total dose of 30 sGy cause partial summation of biological effects assessed by cytogenetic disorders in nuclear cells of the bone marrow and changes in erythrocyte metabolism. The level of cytogenetic damages in bone marrow cells remained increased till day 14 of recovery, whereas following exposure to chemicals or radiation alone the number of chromosomal aberrations (ChA) was nearly same as in control at this point of recovery The anaphase method showed prevalence of ChA in the form of fragments over bridges in marrow karyocites. The combination of factors suppressed energy-producing processes in erythrocytes (reliable reductions in lactate dehydrogenase and lactate) and activated oxidation processes (reliable decrease in reduced glutathione). Functional shifts in erythrocyte metabolism persisted till day 30 of recovery Based on results of the investigation, functional status of organism following low-intensity exposures can be assessed, along with cytogenetic, also by indices of erythrocyte metabolism.

[Red blood of cosmonauts on missions aboard the International Space Station (ISS)].

Morphobiochemical investigations of red blood (space experiment Hematologiya) involved the ISS Russian crew members (increments 6-12). Blood samples were drawn on L-30, at the beginning (FD 6-10) and end (FD 160-190) of orbital flight, shortly after landing (R+0), and on R+7 and R+15. Results of the investigations of red blood metabolism and cell membrane showed that long-duration space flight reduces the hemoglobin level in consequence of, probably, intensive erythropoiesis and premature partial elimination of degraded (possibly old) erythrocytes from circulating blood. High intensity of erythropoises is manifested by an increase in erythropoietin, a decrease in blood iron, and elimination of degraded and old erythrocytes in the course of readaptation to Earth and driven by the growing body demand for oxygen to support muscular work and existence in the gravitational environment in general.

[Morphobiochemical assay of the red blood system in members of the prime crews of the International Space Station].

According to the experiment Hematology protocol, blood samples from the Russian members of ISS prime crews 1 to 5 were gathered on L-30 and R+0, 7, 15 to study metabolic parameters (ATP, reduced glutathione, LHG and glucose-6-phosphate dehydrogenase activities). Lipid spectrum of membrane erythrocytes was determined in frozen erythrocyte mass; iron turnover and erythropoietin were investigated in frozen serum. Ratios of different erythrocyte forms were established in 32 microl of fixated whole blood using scanning electron microscopy. On R+0, the morpho-biochemical parameters of red blood appear to still carry the imprints of space effects and, to an extent, certain difference in the setting of blood sampling from the Mir crew on landing in the space "shuttle" vehicle. Low level of iron and significantly increased erythropoietin on R+0 are the testimony of intensive hemoglobin production and an adequate bone morrow response to the increased oxygen demand. Shifts in erythron are of no clinical implications but indicative of the red blood adaptation to the factors of space fight.

[Cytogenetic and biochemical assay of an unidirectional effect of chronic combined exposure of laboratory animals to isoeffective concentrations of chemical substances].

Chronic combined exposure to low concentrations of chemical substances (equal to the maximal admissible limits for space vehicles) is fraught with an increase in chromosomal aberrations in bone marrow cells as compared with the spontaneous chromosome aberration rate. In addition to the cytogenetic evidence, there were also statistical phase shifts in metabolic parameters of erythrocytes (enzymes involved in the basal metabolism and a number of metabolites), leukocyte count in peripheral blood, and the total quantity of karyocytes in the bone marrow. No significant changes were found in organs of the immune and reproductive systems.

[The combined action of octafluoropropane and bipolar ionized air].

An experiment with Wistar male rats was to look into the action of octafluoropropane (OFP, of 50 microg/m(3)) combined with bipolar ionized air (BIA) at a concentration of light air ions of 60,000 para-air in cm(3). The chamber experiment was 43 days long. Intoxication by OFP reduced body mass, as well as the erythrocyte count and hemoglobin level in peripheral blood. As for BIA, it appeared to bring these indices back to their normal values. Erythrocyte metabolism underwent phase-by-phase shifts; but breathing BIA mitigated these shifts markedly. As regards to erythrocyte metabolism in intoxicated animals, BIA had a compensatory effect Changes in the biochemical profile of blood plasma make us think, that BIA counteracts the OFP damaging action on the myocardium and, at the same time, aggravates impairment of metabolism in the liver and, probably, kidney. Variations in the spectrum and total content of higher fatty acids in the lung in the experiment were more pronounced in the event of exposure to OFP+BIA than to OFP alone. Also, the combined exposure increased the level of laurinic acid. Histological investigations of the liver, spleen, myocardium, trachea and the lung attested to the dystrophic damage of the liver, spleen plethora and reticular hyperplasia, and slight cloudy swelling of the myocardium attributed to OFP. After 14 days since the end of the experiment, histological changes were much less dramatic; in 39 days after the experiment all the changes were gone with the exception of weak emphysematosis. BIA had no effect on animals in the absence of OFP; neither was there any significant difference between control (intact) animals and those who breathed BIA in laboratory. To conclude, 50 microg/m(3) of OFP which falls far short of the existing maximum permissible levels, a strong toxic action on animals. Aside from mitigation of the OFP toxic action on erythrocytes and myocardium, BIA, when breathed with a long time, aggravated the metabolic disorders in the liver and lung provoked by OFP.

Blood serum DNA in patients with rheumatoid arthritis is considerably enriched with fragments of ribosomal repeats containing immunostimulatory CpG-motifs.

We previously hypothesized that the sequence of transcribed region of human ribosomal repeats is selectively accumulated in circulating extracellular DNA due to its increased resistance to double-strand breaks caused by accumulation of single-chain breaks produced by nucleases. The contents of rDNA in blood serum DNA and in DNA from leukocytic nuclei both in healthy donors and in patients with rheumatoid arthritis were compared using dot hybridization method. By the content of non-methylated CpG-repeats, transcribed region of rDNA is identical to bacterial DNA, which is characterized by potent immunostimulatory effect. The transcribed region of rDNA (13.3 kb) contains more than 200 CpG-motifs capable of interacting with TLR9 receptors, which are the mediators of the cell immune response to the action of CpG-rich DNA fragments. The data suggest that DNA from dead cells circulating in the peripheral blood is enriched with sequences possessing potent immunostimulatory properties.

Stimulatory effect of fragments from transcribed region of ribosomal repeat on human peripheral blood lymphocytes.

Fragments from the transcribed region of the ribosomal repeat include considerable amounts of unmethylated CpG DNA motifs. These motifs activate immune cells via the interaction with Toll receptors. In vitro experiments confirmed the stimulatory effect of transcribed region of ribosomal repeat on human lymphocytes. Culturing of lymphocytes in a medium containing 2-20,000 ng/ml fragments from transcribed region of ribosomal repeat was accompanied by structural changes in the nucleus in a considerable number of cells. These changes manifested in translocation of pericentromeric heterochromatin from the membrane to the center of the nucleus and activation of the nucleolus and were accompanied by a significant increase in interleukin-6 production and slight stimulation of tumor necrosis factor-a synthesis. The transcribed region of the ribosomal repeat and E. coli DNA had various effects on quantitative parameters of lymphocytes. Our results suggest the existence of mechanisms of stimulation not mediated by the interaction of CpG DNA motifs with Toll receptors.