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Genomic analysis of methicillin-resistant ceftaroline-resistant Staphylococcus aureus and identification of features of the genetic diversity in representatives of the epidemic ST239 clone circulating in hospitals of the Russian Federation. Species identification was performed using Vitek 2 (bioMerieux). Determination of the sensitivity to antibiotics was carried out using a BD Phoenix semiautomatic bacterial analyzer (United States), and manually to ceftaroline. Whole genome sequencing was performed on the Illumina HiSeq 2500 platform. Data processing and analysis were performed using the following resources: CLC Genomics Workbench, SPAdes, RAST Server, NCBI Prokaryotic Genome Annotation Pipeline, PlasmidFinder, Phaster, BLASTp NCBI, and OrthoMCL. The main characteristics of the SA943 genome, including clusters of resistance genes, factors of pathogenicity, adhesion, invasion, and regulation, were revealed. When analyzing the genome structure, the closest similarity to the representatives of the Eurasian ST239 subclone identified in Turkey, as well as a number of differences from 16K and OC3 strains isolated in Russia earlier, were noted. A unique SSR sequence of the spa gene, which was placed into the database as a new spa type t‑18470, was identified. Substitutions in the amino acid sequence of the gene products of the mec complex, ccrC recombinase, and PBP2 protein, which distinguish SA943 from most ST239 representatives, were revealed. Representatives of several ST239 subclones, including ceftaroline-resistant SA943 belonging to the Eurasian subclone, were identified in hospitals of the Russian Federation. The Eurasian subclone representatives are not a homogeneous group, but differ significantly in the structure of SCCmec and mutations in key antibiotic resistance genes. Whole genome sequencing not only allows one to reveal the features of genome microevolution of epidemic strains in distinct regions, but also to improve the quality of epidemiological analysis and to optimize infection control measures.

The article presents the results of research on the biological activity of gray forest soil depending on the systematic use of organic and mineral fertilizers. It is established that effective reproduction of humus in gray forest soil is provided by organo-mineral (12 t of manure together with N80P60K80 application per 1 ha of crop rotation area) and organic (24 t/ha of manure), respectively 36,5 t/ha, and 35,6 t/ha. The application of only mineral fertilizers in the norm of N80P60K80 per 1 ha of crop rotation area resulted in a decrease in humus reserves by 9 % relative to the initial level (32,4 t/ha). The highest degree of humification of organic matter provided the option of applying organic fertilizers (60 t/ha) both separately – 36,0% and compatible with mineral – (60 t/ha manure + N80P60K80) – 34 %. Prolonged use of organic and mineral fertilizers in crop rotation significantly increased the total number of microorganisms in the soil. The result was increased decomposition of organic matter and increased release of CO2 from the soil. The areas with the highest biological activity and CO2 intensity were characterized by areas where the soil was systematically enriched with fresh organic matter. The intensity of biological processes in the organo-mineral system increased by 67 % relative to the variant without fertilizers and by 30 % relative to the variant with only N80P60K80. The use of organic and mineral fertilizers in one system stimulated the process of decomposition of fiber – at the level of 78,5 %, which in percentage terms exceeded the value of the indicators obtained for a purely mineral fertilizer system.

The species composition, distribution and preservation of carbonate shells of nanno and microfossils of biogenic bottom sediments within the hydrothermal cluster Pobeda (1707.451708.7 n) were studied on the basis of materials obtained in flight No. 37 of NIS Professor Logachev in the Russian exploration area (Mid-Atlantic ridge). Physical-chemical parameters and the total carbonate content of sediments were measured, their changes in column sections were revealed. For complexes of coccoliths studied precipitation is attributed to the top (acme) biostratigraphic zone of Emiliania huxleyi. It is established that within the zone of hydrothermal activity (ore cluster Pobeda) the total number of microorganisms decreases and their species diversity decreases, as a rule, in the lower part of the columns. Down the column section also decreases the Eh, pH and carbonate precipitation. These changes are explained by the influence of diffuse hydrothermal fluids.

Nannofossils were studied, recovered from Late Pliocene–Pleistocene sediments at station 3316 on cruise 46 of the R/V Akademik Ioffe north of the Rio Grande Rise in the Southwest Atlantic. The presence of irregular discoasters in a narrow horizon at the end of the Discoaster brouweri zone of the Upper Pliocene indicates dramatic changes in the living conditions of these organisms, which led to deviations in the regular structure of their skeletons and subsequent extinction at the end of the Pliocene.

The changes in the nomenclature of species in the genus Staphylococcus, including the most pathogenic cluster of the coagulase-positive staphylococci, are represented. Presently, besides S. aureus, this cluster consists of 6 species: S. intermedius, S. schleiferi ssp. coagulans, S. lutrae, S. hyicus, S. pseudintermedius, and S. delphini. A particular attention was paid to the Staphylococcus intermedius group (SIG), which includes three closely related coagulase-positive bacterial species: S. intermedius, S. pseudintermedius, and S. delphini. The hosts of SIG species are various mammals and birds, which live in a close contact with humans. The current knowledge about the virulence factors and pathogenicity for animals and humans are analyzed. The diffic6lties of the species identification, the features of ecology and epidemiology, antimicrobial resistance were reviewed. The biological features of S. pseudintermedius, which has the greatest similarity with S. aureus, are considered in the context of the properties of newly emerging pathogens.

Trawling of the bottom in the northeastern Kara Sea during cruise 125 of the R/V Professor Shtokman in 2013 recovered a block of cavernous, partly phosphatized carbonate rock consisting of biogenic carbonate material and partly crystallized diagenetic calcite. The fauna remains are mainly Oligocene–Pliocene planktonic and benthic foraminifers, with less common Oligocene–Miocene coccoliths and single wormlike organisms. Part of the phosphatized material in caverns is impregnated by manganese and iron oxides and enriched in heavy and trace metals. According to the oxygen isotopic composition, this rock formed under moderate temperature conditions. In terms of morphology, mineralogy, and the abundance of organic remains, the block is comparable to methanogenic carbonates found in other parts of the ocean, but shows no isotopically light carbon signatures typical of methane activity. This indicates the diversity of the carbon isotope composition of the Arctic carbonates.

The paper reports changes in the species nomenclature in the genus Staphylococcus that involve the most pathogenic representatives of the genus, the coagulase-positive staphylococci cluster. To date, this cluster includes six species in addition to Staphylococcus aureus: S. intermedius, S. schleiferi spp. coagulans, S. lutrae, S. hyicus, S. pseudintermedius, and S. delphini. Special attention was given to the representatives of the Staphylococcus intermedius group (SIG), which encompasses three closely related species, S. intermedius, S. pseudintermedius, and S. delphini, whose hosts are mammals and birds living in close proximity to human beings. The current data on the pathogenicity factors and role of SIG representatives in animal and human infectious pathologies were analyzed. The approaches to species identification, together with ecological and epidemiological features, and antibiotic susceptibility were considered. Specific biological features of S. pseudintermedius, the species most similar to S. aureus, are considered from the perspective of the properties of newly emerging pathogens.

Effect of water dispersible single-walled carbon nanotubes on the medullary cardiovascular control was studied in normotensive (control) and spontaneously hypertensive rats using physiological and biochemical approaches. We have shown for the first time the possible contribution of nitric oxide (NO) to single-walled carbon nanotube-induced effects in the cardiovascular nuclei of the medulla oblongata (the lateral reticular nucleus and nucleus ambiguous). The data of biochemical experiments indicate that single-walled carbon nanotubes added to the medulla oblongata homogenates induce an enhancement of constitutive nitric oxide-synthase (cNOS) activity, which is mostly neuronal nitric oxide-synthase (nNOS) in the brain, and an increase in the level of nitrite (NO–2), a stable nitric oxide metabolite which serves nitric oxide bioavailability marker. In physiological experiments, it has been revealed that effects of single-walled carbon nanotube injection in the cardiovascular nuclei under study are attenuated after preliminary nNOS inhibiting. An analysis of single-walled carbon nanotube-induced changes in the levels of malonic dialdehyde, an oxidative stress marker, as well as the levels of reactive nitrogen species (pools of nitrate anions), and the activity of Ca2+-independent inducible nitric oxide synthase (iNOS) has indicated that single-walled carbon nanotubes used in the study do not promote oxidative and nitrosative stress in control and spontaneously hypertensive rats.

The analysis of calcareous nannoplankton assemblages in bottom sediments sampled during Cruise 21 of the R/V Akademik Mstislav Keldysh in three areas located in back-arc basins of the southwestern Pacific (western Woodlark in the Solomon Sea, Manus in the Bismarck Sea, Central Lau) reveal that they belong to the Emiliania huxleyi Acme Zone, the most detailed one in the Gartner’s scale of 1977. The content of coccoliths and their taxonomic composition indicate warm subtropical-tropical conditions. Long cores demonstrate a decrease in species diversity reflecting the transition from the cold late Pleistocene to the Holocene. The changes in species diversity and presence/absence of thermophilic representatives indicate transformation of depositional environments with unstable conditions in the water column and bottom layer, seismic activity, and widely developed processes of sediment redistribution and reworking.

The chemical and mineral composition of the bottom sediments, as well as the assemblages of carbonate planktonic and benthic fossils (nannoplankton, foraminifers), were analyzed in two cores obtained in the North Atlantic within the Peterburgskoe hydrothermal ore field and beyond its limits. Their sections include the Upper Pleistocene and Holocene sediments with the boundary between them located at the depth of 20 cm. It is established that planktonic fossils (foraminifers and nannoplankton) reflect the replacement of subtropical conditions in the Late Pleistocene by tropical environments in the Holocene. It is shown that hydrothermal fluids significantly affect biogenic carbonate sediments in the ore formation zone of the Peterburgskoe field (core 33L159) resulting in dissolution of microfossils and their replacement by hydrothermal material. Their transformation patterns and vertical distribution indicate the influx of diffuse acid solutions to sediments from below. In background sediments constituting the core 33L148 section located 5 km away from the ore field, microfossils exhibit good preservation through its entire length. The sediments from the basal part of the section demonstrate the slight influence of the aggressive acid medium reflected in the disappearance of pteropod remains and changes in the abundance and taxonomic composition of benthic foraminifers and nannofossils. These data may be used as a criterion for defining potential nearby active hydrothermal sources.

The spectra of capillary waves were studied for bidistilled water and a NADH aqueous solution, and their dynamics under electromagnetic irradiation in the millimeter range was determined at different space frequencies of the surface wave k.

The development of molecular techniques of research in the end of XX century permitted to broaden nomenclature of species forming genus Staphylococcus that nowadays numbers 51 species and 27 sub-species. The pathogenic species of genus have a capacity to coagulate blood plasma of mammals forming group of coagulase-positive staphylococci including 7 species: S. aureus, S. delphini, S. intermedius, S. pseudintermedius, S. lutrae, S. schleiferi ssp. сoagulans, S hyicus. In clinical practice, S.aureus is considered as the most virulent among staphylococci. The cumulated data testifies increasing etiologic significance of other representatives of group of coagulase-positive staphylococci in human and animal infection pathology. The keen attention is needed to be paid to Staphylococcus intermedius of group (SIG), uniting three close kindred species: S. pseudintermedius, S. intermedius, S. delphini. Among them the most broadly prevailed are methicillin-resistant clones of S. pseudintermedius, capable to bring on in patient various pyoinflammatory diseases. The laboratory methods based on phenotype tests, provide no opportunity to differentiate coagulase-positive staphylococci because of significant similarity of phenotype characteristics in certain representatives of this group. Te comparative analysis was implemented concerning efficiency of various methods of species identification of coagulase-positive staphylococci: biochemical, molecular genetic (multi-primer polymerase chain reaction for identifying differences in gene structure of thermonuclease, analysis of polymorphism of lengths of restricting fragments of catalase gene and their sequencing), matrix-activated laser desorptional/ionizing time-of-flight mass-spectrometry (MALDI-ToF MS) with various modes of probe preparation. The analysis was applied to 117 isolates of representatives of SIG, separated from ill and healthy individuals of small domestic animals, clinical isolates form patients of hospitals. The multi-primer polymerase chain reaction permitted to identify 97% of isolates, analysis of polymorphism of lengths of restricting fragments of catalase gene - 100% of isolates that confirms efficiency of molecular genetic methods of analysis. The MALDI-ToF MS requires replenishment data base of mass-spectrometer and application of the mode of preliminary protein extraction of samples fo increasing efficiency of species identification of coagulase-positive staphylococci.

A highly sensitive test system, based on the immuno-PCR method, was developed for the detection of two staphylococcal toxins: enterotoxin A (SEA) and toxic shock syndrome toxin (TSST). A key element of the developed systems was to obtain supramolecular complexes of bisbiotinylated oligodeoxynucleotides and streptavidin, which were to be used as DNA-tags. Specificity studies showed no cross-reactivity when determining SEA and TSST. The sensitivity of detection of these toxins in the culture supernatants S. aureus was not lower than 10 pg/mL.

Reference cores of sediments from the Angola and Cape basins were subjected to lithological, geochemical, and micropaleontological investigations. Based on nannofossil and diatom assemblages, the examined sediments represented by oxidized miopelagic clays, calcareous (nannofossil-foraminiferal, foraminiferal-nannofossil), calcareous-clayey, and clayey-calcareous mud are estimated to be the Pleistocene-Holocene in age. The Cape Basin section includes surface and buried ferromanganese nodules. There are indications of sedimentary material redeposition by the Antarctic Bottom Water and turbidity currents. The South Polar Front zone changed repeatedly its geographic position and migrated northward from the presentday one. As a whole, the Pleistocene-Holocene sedimentation in the Angola and Cape basins corresponds to the incomplete pelagic (miopelagic) type of oceanic lithogenesis.

The study of the upper part of the section of borehole 362 DSDP (southeastern Atlantic) allowed the recognition of five zonal units in the Quaternary based on nannofossils and refinement of the UpperLower Pleistocene boundary based on benthic foraminifers. The study of planktonic and benthic foraminifers in sediments display the history of the Benguela upwelling. The temperature of the surface water layer reconstructed based on Upper Pleistocene planktonic foraminifers reaches 17°–19°C and decreases downward in the section to 2°–3°C, suggesting that, in the Early Pleistocene, the upwelling was more extensive in area. The increasing proportion of benthic foraminifers and large nannofossils downward in the section is evidence of more active dissolution of carbonates in the Early Pleistocene and the high content of terrigenous matter suggests that the Benguela Current occupied a westerly position. The existence of the Benguela upwelling throughout the Late Pliocene-Pleistocene was accompanied by a decrease in its activity.

Photogeneration of electric charge carriers at high strengths of the external electric field and the temperature of transition to the viscous-flow state (T visc) of thin PEPC-C60 composite films obtained by casting from a toluene solution have been studied. The rheology of the composite films has been investigated by the nondestructive optical method. The consistent correlated change in the values of T visc and the effective temperature in the expression for the photogeneration quantum yield (T 0) in the Meltz representation with variations in the C60 concentration has been established. The difference between T visc and T 0 in thin composite films does not exceed 2–3% of T visc (T 0).

The effect of single-walled carbon nanotubes (SWCNTs) on the nervous cardiovascular control in normotensive (NTR) and spontaneously hypertensive rats (SHR) was studied. SWCNTs were injected into the medullary nuclei involved in the neural control of the cardiovascular system (nucleus of tractus solitarius (NTS); nucleus ambiguus (AMB), paramedian reticular nucleus (PMn), and lateral reticular nucleus (LRN)). It was found that SWCNT microinjections into all the studied medullary nuclei of both NTR and SHR resulted in a lowering of the arterial pressure more essential in SHR compared to those in NTR. Der Einfluss von einwandigen Kohlenstoffnanorohren (SWCNTs) auf die kardiovaskulare Nervenkontrolle in normotonen (NTR) und spontan hypertonen Ratten (SHR) wurde untersucht. Die SWCNTs wurden in medullare Kerne injiziert, die an der neuronalen Kontrolle des Herz-Kreislauf-Systems beteiligt sind (Nucleus des Tractus solitarius (NTS); Nucleus ambiguus (AMB); paramedianer retikularer Nucleus (PMn); Nucleus reticularis lateralis (LRN)). Die SWCNT-Mikroinjektionen in samtliche untersuchte medullare Kerne fuhrten sowohl bei den NTR als auch bei den SHR zu einer Absenkung des Arteriendrucks, in starkerem Mase bei den SHR verglichen mit den NTR.

The foraminiferal (planktonic and benthic) and nannofosssil assemblages have been analyzed in the sediments of Core ACB-17-1447 taken from the South America continental slope north of the Rio Grande Rise piedmont during Cruise 17 of the R/V Akademik Sergey Vavilov. The core section is largely composed of carbonate and marly hemipelagic mud. The Quaternary age of the host sediments is evident from the occurrence of the planktonic foraminiferal index species Globorotalia truncatulinoides. Based on the nannofossil assemblages, the core sediments are attributed to the upper Pleistocene-Holocene. They contain abundant reworked Pliocene, Miocene, and Paleogene taxa transported from the slopes of the underwater Rio Grande Rise. The paleotemperature analysis of the planktonic foraminifers provided data for constructing the temperature curve that demonstrates two warm peaks. During the first warm period (Interval of 7–9 cm), the surface water temperature was as high as 26°C (Holocene optimum), which exceeds by 3–4°C its presentday values and implies the more intense warm Brazil Current. The earlier warm peak with temperatures up to 24°C recorded in the upper Pleistocene sediments (Interval of 69–71 cm) most likely reflects the 3rd oxygenisotope stage (MIS 3), which corresponds to the interstadial phase of the last glaciation (30–40 ka ago). Based on the abundances, taxonomic diversity, and proportions of the characteristic species of benthic foraminifers, the Core ASV-17-1447 section is divided into six intervals correlated with the marine isotopic stages defined by both the planktonic foraminifers and climatic changes evident from the variations in the bottom water circulation along the southwestern slope of the Brazilian Basin during the Late Quaternary.

The nannofosssil assemblages have been analyzed in five cores taken from the Titanic area of the northwestern Atlantic (∼41°–42° N, ∼47°–50° W, water depths >3500 m) during cruises 41 and 43 of the R/V Akademik Mstislav Keldysh in 1998 and 2000. They correlate the host sediments with the upper Pleistocene-Holocene Emiliania huxleyi zone. The changes in the structure of the nannofossil assemblages and the lithological characteristics such as the content of biogenic CaCO3, the abundance of ice-rafted debris, and the grain-size composition were used for the high-resolution stratigraphy of sections with defining marine isotopic stages 1–3 of the last 24 kyr. A characteristic feature of the nannofossil assemblages from this area is their enrichment with the cold-resistant species Coccolthus pelagicus during the warm climatic stages and the lack of allochthonous coccolitophorid remains.

Analysis of carbonate microfossils (planktonic foraminifers and nannoplankton) in the DSDP Hole 362 Quaternary section made it possible to specify its zonal subdivision (almost all zones of Gartner’s high-resolution nannofossil scale are recognized), establish depositional environments, and restore past surface water temperatures. The latter appeared to be several degrees lower than their present-day values, which is evident from the anomalously high share of the subpolar species Neogloboquadrina pachyderma sin. that constitutes 97% of the fossil assemblage in Lower Pleistocene sediments. It is shown that the Benguela upwelling existed throughout the entire Pleistocene, being less intense in the Late Pleistocene and Holocene.

The first thorough analysis of microfossils from ore-bearing sediments of the Ashadze-1 hydrothermal field in the Mid-Atlantic Ridge sampled during cruise 26 of the R/V Professor Logachev in 2005 revealed the substantial influence of hydrothermal processes on the preservation of planktonic calcareous organisms, as well as on the preservation and composition of the benthic foraminifers. From the lateral and vertical distribution patterns and the secondary alterations of the microfossils, it is inferred that the main phase of the hydrothermal mineralization occurred in the Holocene. Heavy metals (Cu, Co, Cr, and Ag) were accumulated by foraminiferal tests and in their enveloping Fe-Mn crusts. The distribution of authigenic minerals replacing foraminiferal tests demonstrates local zoning related to the hydrothermal activity. There are three mineral-geochemical zones defined: the sulfide zone, the zone with an elevated Mg content, and zone of Fe-Mn crusts.

The fine structure of the fundamental vibrational bands and some combination tones of fullerite C60 in its IR absorption and reflection spectra, as well as in Raman spectra, has been studied. This structure is due to the overlapping components of Davydov and isotopic splittings and the removal of vibrational degeneracy with symmetry lowering. It is shown that for IR Fu(i) bands (i = 1–4) and low-frequency Hg(1) and Ag(1) bands in the Raman spectrum the splittings at room temperature exceed those for the low-temperature phase. The enhancement of intermolecular interaction at elevated temperatures is explained by the nonequilibrium vibrational excitation of the medium as a result of nonlinear interaction of vibrational modes and by the change in the electronic states.

The influence of the fullerene content and temperature on the IR absorption and luminescence spectra of poly(N-vinylcarbazole) (PVK)-C60 composites prepared by vacuum deposition has been studied. It has been demonstrated that the luminescence spectra of the composites produced by vacuum deposition on substrates differ significantly from the spectra of the samples prepared by pouring of a toluene solution of PVK on the same substrates and the spectra of the samples synthesized by deposition in an inert gas atmosphere. The explanation for this phenomenon has been proposed. It has been revealed that the sizes of the structures absorbing IR radiation increase with an increase in the C60 concentration in PVK-C60 layers. It has been experimentally proved that, under the influence of light with a wavelength of 514.5 nm, the PVK-C60 composites undergo photoinduced reversible changes, which lead to nontrivial concentration-dependent changes in the luminescence spectrum.

A complex of lithological and micropaleontological methods were used for the study of sediments from the central North Atlantic (50–60°N). The data on the lithology, carbonate content, and occurrence of ash interbeds and ice-rafted material, combined with the nannofossil zonal biostratigraphy, allowed detailed subdivision of five core sections obtained during Cruise 48 of R/V Akademik Mstislav Keldysh. MIS 1–MIS 9 are established in the sections. In some of them, climatic changes related to migrations of the Subarctic Front are established based on the lithology and the characteristic coccolithophorid species: for example, a higher latitudinal position of the front is revealed for the Eemian interglacial (Substage 5e) as compared with that in the Holocene.

Diatom and nannoplankton microfossils in the samples of the surface bottom sediments and cores from the western part of the Norwegian Sea (64°–79°N) were studied. The abundance, distribution, taxonomic composition, and structure of the assemblages are determined by the productivity and temperature of the surface waters, by the distance from the shore, by the hydrological setting, and by the intensity of the supply of the Atlantic (from the south) and Arctic (from the north) waters to the Norwegian Sea. The repeated changes in the ecological structure of the diatom assemblages with time allowed us to distinguish five different ages and to estimate the changes in the paleoenvironment in the region under study during the past ∼19–21 ky. The nannofossil distribution is not universal over the entire area studied owing to the extreme northern location of the stations and low water temperatures. All the sediments examined refer to the Emiliania huxleyi zone of the Late Pleistocene-Holocene; in selected cases, narrower temperate and cold-water intervals were also recognized. The low species diversity and the poor preservation of nannofossils prove the dominating influence of the Arctic water masses.

The kinetics of photogeneration of electric charge carriers in organic molecular semiconductors in strong electric fields is investigated within a theoretical model that includes the diffusion-drift mechanism of motion of electric charge carriers. In the framework of the proposed model, it is established that the time dependence of the probability of dissociation of a geminal pair exhibits an exponential behavior. The time constant strongly depends on the electric charge carrier hopping distance and the external electric field strength in accordance with the experimental data.

Calcareous nannoplankton from sediment trap samples collected at six sites in the Atlantic Ocean from 23° S to 73° N (cruise 20 of R/V Vityaz’ and cruise 33 and 34 of R/V Akademik Mstislav Keldysh). Those samples were studied with a scanning electron microscope. In the coastal and open-sea regions of the North and South Atlantic and in the subarctic region of the Norwegian Sea, the conditions are significantly different. In the shelf area of the Benguela upwelling, 11 species were recognized; some of them were agglutinated by diatoms and tintinnides or covered the surface of pellets. The Broken Spur and TAG pelagic areas of the North Atlantic contained up to 43 coccolith species. They included holococcoliths, large pelagic, and delicate easily soluble species distributed over the entire water column. The presence of coccoliths in the high-latitude area of the Norwegian Sea is related to their supply with the warmer North Atlantic waters. These assemblages are distinguished by a low species diversity and an enhancement of the coccolith solubility with the depth increase.

In acute experiments on anesthetized (urethane) normotensive rats, we studied the hemodynamic effects of unilateral microinjections of a nitric oxide (NO) donor, sodium nitroprusside, into the medullary nuclei participating in central cardiovascular control. We studied also the effects of modulation of the intensity of NO production: enhancing its synthesis by intramedullary injections of exogenous L-arginine or inhibiting this process with an inhibitor of neuronal NO synthase (nNOS), L-NNA, or with an inhibitor of arginase, norvaline. Intramedullary injections of the above agents were confined to the nucleus of the tractus solitarius, dorsal motor nucleus of the vagus, nucleus ambiguous, and lateral reticular nucleus. We tried to evaluate the possibility of production of NO from L-arginine in central neurons of normotensive rats via not only the well-known NO synthase pathway, but also via an alternative arginase-mediated pathway of metabolism of the above amino acid. Our results demonstrated that both enzymes are potentially active: injections of the mentioned inhibitors of the enzymes into the medullary neuronal structures induced marked shifts in the systemic arterial pressure (SAP), the integrative parameter characterizing the state of the cardiovascular system. After preliminary administration of an nNOS inhibitor, 7-nitroindazole (30 mg/kg, i.p.) or an inhibitor of arginase, norvaline (2 μg, i.v.), injections of L-arginine into the medullary nuclei failed to evoke significant shifts in the SAP. We suggest that the comparative degree of activation of nNOS or arginase in the medullary nuclei depends on different factors, first of all on the level of oxygenation of the nerve tissue. An inverse dependence is likely to exist between the levels of activation of the above enzymes.

Stability of vitamin D3 on aerosil surfaces has been studied by UV- and IR-spectroscopy. The difference in the thermobehaviour of vitamin D3 in the adsorbed state at low and high surface coverages has been observed and discussed in terms of the competition between vitamin D3 molecules and their thermoisomers for the adsorption sites.

The ground-state conformational analysis of previtamin D, its E-isomer, tachysterol, their 10-desmethyl analogues and 1-methyl-1-hydroxy-previtamins have been performed by force-field calculations. Differences in the absorption characteristics of these compounds are discussed in view of the chromophore geometry and abundance (%) of the calculated conformers according to a Boltzmann distribution at 298 K. On the basis of present calculations, the red shift of previtamin D low-temperature UV and CD spectra determined earlier is attributed to the shift of conformational equilibrium in favour of more stable cZc geometries. The effect of complex formation with simplest model cluster of silica surface ((H3SiO)3SiOH), on previtamin D and tachysterol conformational equilibria and on UV-absorbance maxima has been evaluated.

The changes in the nomenclature of species in the genus Staphylococcus, including the most pathogenic cluster of the coagulase-positive staphylococci, are represented. Presently, besides S. aureus, this cluster consists of 6 species: S. intermedius, S. schleiferi ssp. coagulans, S. lutrae, S. hyicus, S. pseudintermedius, and S. delphini. A particular attention was paid to the Staphylococcus intermedius group (SIG), which includes three closely related coagulase-positive bacterial species: S. intermedius, S. pseudintermedius, and S. delphini. The hosts of SIG species are various mammals and birds, which live in a close contact with humans. The current knowledge about the virulence factors and pathogenicity for animals and humans are analyzed. The diffic6lties of the species identification, the features of ecology and epidemiology, antimicrobial resistance were reviewed. The biological features of S. pseudintermedius, which has the greatest similarity with S. aureus, are considered in the context of the properties of newly emerging pathogens.

S. aureus, S. pyogenes, P. aerugenosa, E. coli, P mirabilis, A. baumannii, S. epidermidis, K. pneumoniae, E. faecalis, E. cloacae are the priority pathogens of various forms of pyoinflammatory diseases. They form the architectonics of microbe ecology of the purulent surgery department of multi-type hospital of regional level with S.aureus subsp.aureus playing dominating role. In case of unchanged specter of priority pathogens of pyoinflammatory and pyoseptic diseases the number of gram-positive coccuses decreases at the expense of decrease of number of streptococcuses and staphylococcuses. At the same time, the number of enterobacteria and gram-negative non-fermentative bacteria increases. The resistance ofgram-positive coccuses increases regarding erythromycin, clyndamicin and cyprofloxacin. The resistance of gram-negative bacilli increases regarding ciprofloxacin, cephalosporins of III-IV generations, amikacin. The resistance is the highest among clinical isolates MRSA, K. pneumoniae, A. baumannii. The vancomycin is active regarding all gram-positive pathogens. The carbapenems are active regarding all enterobacteriae. The carbapenems, cefoperazone/tazobactam, cefepime are most active regarding non-fermentative glucose oxidizing bacteria. The netimicin is active regarding A.baumannii. The polymyxine is active regarding P. aerugenosa. The circulation of S. aureus hospital strain of particular genotype is established confirming the propagation of epidemic S. aureus strains in Moscow multi-type medical institutions. The strains are genetically affined to epidemic strains in European and other countries according the international data base (http://SpaServer.ridom.de). The genetic typing of S. aureus ssp. aureus out-hospital hemocultures detected their considerable genetic variety. The epidemic relationship between isolates from different patients is not established. The algorithms of rationale antibacterial chemotherapy of pyoinflammatory and pyoseptic diseases are developed to be implemented in the purulent surgery department of municipal clinical hospital of Moscow.

The paper deals with theoretical study of phenomenon of loneliness. The psychological features of teenagers’ loneliness experiencing are analyzed. The results of empiric research of interrelation feeling of loneliness with individual-psychological characteristics are presented.

A theoretical basis has been provided for the possibility of effecting conformational control of the products of the photochemical transformations of provitamin D by acting expressly on the conformational equilibrium of the previtamin molecule by causing an interaction with an appropriate reaction medium. The results of the analysis that was carried out are valid for any extended photoreaction with a conformationally fluxional intermediate.

Development of Staphylococcus haemolyticus strain typing method based on multilocus sequencing for resolving problems of molecular epidemiology.102 strains of coagulase negative staphylococci (CNS) isolated in hospitals of various specialization in N. Novgorod and Moscow were studied. Species identification of strain was performed by using tuf gene fragment sequencing, S. haemolyticus strain differentiation--by MLST results. eBURST approach was used for cluster analysis of MLST data; structural changes in tagatose-6-phosphate kinase were studied by using InterProScan platform and SWISS-MODEL site programs; MLST scheme gene allele variability analysis was performed by using MEGA4.0 program package.In the 102 strains sampled CNS was detected in 28 strains of the S. haemolyticus species. The MLST scheme developed for the first time for S. haemolyticus including mvaK, rphE, tphK, gtr, arcC, triA, aroE genes allowed the differentiation of the sampled strains by 11 genotypes. Strains with ST 3, 8, 6, 1, 4, 5 and 11 differed by highest epidemiologic significance. Cluster and phylogenetic analysis of the data obtained showed a high adaptive ability of the nosocomial S. haemolyticus strains. Multiresistance to antibacterial preparations was detected in the analyzed strains.The MLST method developed was effective in the differentiation of S. haemolyticus strains that circulate in hospitals and threaten both neonates and hospitalized adult patients.

The content of methicillin resistant S. aureus (MRSA) genes, coding the synthesis of staphylococcal enterotoxins A, B, C (sea, seb, sec) and the toxin of the toxic shock syndrome (tst-H) which was classified with pyrogenic toxins of superantigens (PTSAgs), was studied with the use of PCR amplification. The study revealed the specific features of the content of genes sea and sec, detected in epidemic strains, identified earlier and found to circulate in Russian hospitals. Among the isolates, genetically related to international epidemic strain EMRSA-1, isolates containing no gene sea were detected, while among the isolates genetically related to strain EMRSA-2, isolates containing not only gene sea, but also gene sec were detected, which was indicative of the tendence of this epidemic strain in the direction of further acquisition of pathogenicity genes. As revealed in further studies, among the cultures obtained in bacteriemia, 88% contained gene sea. Two out of three isolates obtained from patients with the symptoms of toxic shock also contained this gene. The differences in the content of genes PTSAgs (sea, seb, sec and tst-H) could serve as a genetic criterium for the differention of isolates circulating in a hospital, as well as for a more complete characterization of the epidemic strains MRSA. The determination of the given genetic markers in genetic strains in circulating strains will make it possible to prognosticate the structure, severity and outcomes of hospital infections. The conditions of PCR amplification for the determination of genes sea, seb, sec and tst-H, as well as multiplex PCR for the determination of genes sea and seb, were developed.