Publications by authors named "Perevalova A"

MicroRNAs play a significant role in the development of cancers, including lung cancer. A recent study revealed that smoking, a key risk factor for lung cancer, increased the levels of hsa-mir-301a in the tumor tissues of patients with lung squamous cell carcinoma (LUSC). The aim of the current study is to investigate the mechanism by which tobacco smoke increases hsa-mir-301a levels in LUSC tumor tissues using bioinformatics analysis.

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Smoking is an established risk factor for a variety of malignant tumors, the most well-known of which is lung cancer. Various molecular interactions are known to link tobacco smoke exposure to lung cancer, but new data are still emerging on the effects of smoking on lung cancer development, progression, and tumor response to therapy. In this study, we reveal in further detail the previously established association between smoking and hsa-mir-301a activity in lung squamous cell carcinoma, LUSC.

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IRF1 is a transcription factor well known for its role in IFN signaling. Although IRF1 was initially identified for its involvement in inflammatory processes, there is now evidence that it provides a function in carcinogenesis as well. IRF1 has been shown to affect several important antitumor mechanisms, such as induction of apoptosis, cell cycle arrest, remodeling of tumor immune microenvironment, suppression of telomerase activity, suppression of angiogenesis and others.

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The electrical resistivity and the Hall effect of topological insulator BiTe and BiSe single crystals were studied in the temperature range from 4.2 to 300 K and in magnetic fields up to 10 T. Theoretical calculations of the electronic structure of these compounds were carried out in density functional approach, taking into account spin-orbit coupling and crystal structure data for temperatures of 5, 50 and 300 K.

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Activation of the constitutive androstane receptor (CAR, NR1I3) by chemical compounds induces liver hyperplasia in rodents. 1,4-Bis[2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP), a mouse CAR agonist, is most often used to study chemically induced liver hyperplasia and hepatocyte proliferation in vivo. TCPOBOP is a potent murine liver chemical mitogen, which induces rapid liver hyperplasia in mice independently of liver injury.

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Phosphatase and tensin homolog deleted on chromosome 10 (PTEN), is a tumor suppressor inactivated in a variety of human cancers. PTEN alteration correlates with lung squamous-cell carcinoma (LUSC) histology. However, it is still unclear how tobacco smoke regulates PTEN in LUSC tissues.

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Tumor-suppressive effects of PTEN are well-known, but modern evidence suggest that they are not limited to its ability to inhibit pro-oncogenic PI3K/AKT signaling pathway. Features of PTEN structure facilitate its interaction with substrates of different nature and display its activity in various ways both in the cytoplasm and in cell nuclei, which makes it possible to take a broader look at its ability to suppress tumor growth. The possible mechanisms of the loss of PTEN effects are also diverse - PTEN can be regulated at many levels, leading to change in the protein activity or its amount in the cell, while their significance for the development of malignant tumors has yet to be studied.

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Using a sample from a terrestrial hot spring (pH 6.8, 60 °C), we enriched a thermophilic microbial consortium performing anaerobic autotrophic oxidation of hydrothermal siderite (FeCO), with CO/bicarbonate as the electron acceptor and the only carbon source, producing green rust and acetate. In order to reproduce Proterozoic environmental conditions during the deposition of banded iron formation (BIF), we incubated the microbial consortium in a bioreactor that contained an unmixed anoxic layer of siderite, perfectly mixed N/CO-saturated liquid medium and microoxic (2% O) headspace.

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Cultivation and molecular approaches were used to study methanogenesis in saline aquatic system of the Lake Elton (southern Russia), the largest hypersaline lake in Europe. The potential rates of hydrogenotrophic, acetoclastic, methylotrophic and methyl-reducing methanogenesis and diversity of the growth-enriched for by adding electron donors methanogenic communities were studied in the sediment slurry incubations at salinity range from 7 to 275 g/L. The most active pathway detected at all salinities was methylotrophic with a dominance of Methanohalobium and Methanohalophilus genera, at salt saturation and moderately halophilic Methanolobus and Methanococcoides at lower salinity.

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Redox-active iron minerals can act as energy sources or electron-transferring mediators in microbial syntrophic associations, being important means of interspecies metabolic cooperation in sedimentary environments. Alkaline conditions alter the thermodynamic stability of iron minerals, influencing their availability for interspecies syntrophic interactions. We have modeled anaerobic alkaliphilic microbial associations in ethanol-oxidizing co-culture of an obligate syntroph Candidatus "Contubernalis alkalaceticum" and a facultative lithotroph Geoalkalibacter ferrihydriticus, which is capable of dissimilatory Fe(III) reduction and homoacetogenic oxidation of Fe(II) with CO.

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Z-533, a hyperthermophilic crenarcheon, ferments peptide and starch, generating acetate, isobutyrate, isovalerate, CO, and hydrogen. Unlike Z-1312, it cannot use cellulose and is inhibited by hydrogen. The reported draft genome sequence of Z-533 will help to understand the molecular basis for these differences.

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Microbial communities of Kamchatka Peninsula terrestrial hot springs were studied using molecular, radioisotopic and cultural approaches. Analysis of 16S rRNA gene fragments performed by means of high-throughput sequencing revealed that aerobic autotrophic sulfur-oxidizing bacteria of the genus Sulfurihydrogenibium (phylum Aquificae) dominated in a majority of streamers. Another widely distributed and abundant group was that of anaerobic bacteria of the genus Caldimicrobium (phylum Thermodesulfobacteria).

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A moderately thermophilic, anaerobic bacterium designated as strain KRT was isolated from a shallow-water submarine hydrothermal vent (Kunashir Island, Southern Kurils, Russia). Cells of strain KRT were thin (0.2-0.

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An obligately anaerobic, hyperthermophilic, organoheterotrophic archaeon, strain 1633, was isolated from a terrestrial hot spring of the Uzon Caldera (Kamchatka Peninsula, Russia). Cells were regular cocci, 0.5-0.

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Representatives of the crenarchaeal genus Desulfurococcus are strictly anaerobic hyperthermophiles with an organotrophic type of metabolism. Since 1982, five Desulfurococcus species names have been validly published: Desulfurococcus mucosus, D. mobilis, D.

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The complete genome of the obligately anaerobic crenarchaeote Fervidicoccus fontis Kam940(T), a terrestrial hot spring inhabitant with a growth optimum of 65-70 °C, has been sequenced and analyzed. The small 1.3-Mb genome encodes several extracellular proteases and no other extracellular hydrolases.

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Desulfurococcus fermentans is the first known cellulolytic archaeon. This hyperthermophilic and strictly anaerobic crenarchaeon produces hydrogen from fermentation of various carbohydrates and peptides without inhibition by accumulating hydrogen. The complete genome sequence reported here suggested that D.

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A novel thermophilic bacterium, strain Kam1851(T), was isolated from a terrestrial hot spring of the Uzon Caldera, Kamchatka Peninsula, Russia. Cells of strain Kam1851(T) were spore-forming rods with a gram-positive type of cell wall. Growth was observed between 46 and 78 °C, and pH 5.

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The thermoacidophilic microbial community inhabiting the groundwater with pH 4.0 and temperature 50°C at the East Thermal Field of Uzon Caldera, Kamchatka, was examined using pyrosequencing of the V3 region of the 16S rRNA gene. Bacteria comprise about 30% of microorganisms and are represented primarily by aerobic lithoautotrophs using the energy sources of volcanic origin--thermoacidophilic methanotrophs of the phylum Verrucomicrobia and Acidithiobacillus spp.

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Processes of inorganic carbon assimilation, methanogenesis, sulfate reduction, and acetate oxidation to CO(2) occurring in samples from the East Pacific Rise at 13°N were traced, using radioisotopically labeled substrates, at temperatures ranging from 65 to 100°C. Molecular hydrogen stimulated lithotrophic methanogenesis and sulfate reduction but inhibited inorganic carbon assimilation. Active mineralization of acetate was observed in an organic-rich Alvinella-associated system at 80°C.

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Two novel thermophilic and slightly acidophilic strains, Kam940(T) and Kam1507b, which shared 99 % 16S rRNA gene sequence identity, were isolated from terrestrial hot springs of the Uzon caldera on the Kamchatka peninsula. Cells of both strains were non-motile, regular cocci. Growth was observed between 55 and 85 degrees C, with an optimum at 65-70 degrees C (doubling time, 6.

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Samples of water from the hot springs of Uzon Caldera with temperatures from 68 to 87 degrees C and pHs of 4.1 to 7.0, supplemented with proteinaceous (albumin, casein, or alpha- or beta-keratin) or carbohydrate (cellulose, carboxymethyl cellulose, chitin, or agarose) biological polymers, were filled with thermal water and incubated at the same sites, with the contents of the tubes freely accessible to the hydrothermal fluid.

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Culture-independent (PCR with Crenarchaeota-specific primers and subsequent denaturing gradient gel electrophoresis) and culture-dependent approaches were used to study the diversity of Crenarchaeota in terrestrial hot springs of the Kamchatka Peninsula and the Lake Baikal region (Russia) and of Iceland. Among the phylotypes detected there were relatives of both cultured (mainly hyperthermophilic) and uncultured Crenarchaeota. It was found that there is a large and diverse group of uncultured Crenarchaeota that inhabit terrestrial hot springs with moderate temperatures (55 to 70 degrees C).

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Glycerol dialkyl glycerol tetraethers (GDGTs) found in hot springs reflect the abundance and community structure of Archaea in these extreme environments. The relationships between GDGTs, archaeal communities, and physical or geochemical variables are underexamined to date and when reported often result in conflicting interpretations. Here, we examined profiles of GDGTs from pure cultures of Crenarchaeota and from terrestrial geothermal springs representing a wide distribution of locations, including Yellowstone National Park (United States), the Great Basin of Nevada and California (United States), Kamchatka (Russia), Tengchong thermal field (China), and Thailand.

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An obligately anaerobic, hyperthermophilic, organoheterotrophic archaeon, strain Z-1312(T), was isolated from a freshwater hot spring of the Uzon caldera (Kamchatka Peninsula, Russia). The cells were regular cocci, 1-4 microm in diameter, with one long flagellum. The cell envelope was composed of a globular layer attached to the cytoplasmic membrane.

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