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1.
Microb Ecol ; 83(4): 899-915, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34255112

RESUMO

This article presents the first experimental data on the ability of microbial communities from sediments of the Gorevoy Utes natural oil seep to degrade petroleum hydrocarbons under anaerobic conditions. Like in marine ecosystems associated with oil discharge, available electron acceptors, in particular sulfate ions, affect the composition of the microbial community and the degree of hydrocarbon conversion. The cultivation of the surface sediments under sulfate-reducing conditions led to the formation of a more diverse bacterial community and greater loss of n-alkanes (28%) in comparison to methanogenic conditions (6%). Microbial communities of both surface and deep sediments are more oriented to degrade polycyclic aromatic hydrocarbons (PAHs), to which the degree of the PAH conversion testifies (up to 46%) irrespective of the present electron acceptors. Microorganisms with the uncultured closest homologues from thermal habitats, sediments of mud volcanoes, and environments contaminated with hydrocarbons mainly represented microbial communities of enrichment cultures. The members of the phyla Firmicutes, Chloroflexi, and Caldiserica (OP5), as well as the class Deltaproteobacteria and Methanomicrobia, were mostly found in enrichment cultures. The influence of gas-saturated fluids may be responsible for the presence in the bacterial 16S rRNA gene libraries of the sequences of "rare taxa": Planctomycetes, Ca. Atribacteria (OP9), Ca. Armatimonadetes (OP10), Ca. Latescibacteria (WS3), Ca. division (AC1), Ca. division (OP11), and Ca. Parcubacteria (OD1), which can be involved in hydrocarbon oxidation.


Assuntos
Euryarchaeota , Microbiota , Petróleo , Anaerobiose , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Euryarchaeota/genética , Sedimentos Geológicos/microbiologia , Hidrocarbonetos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Sulfatos/metabolismo
2.
Microbiome ; 8(1): 163, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213521

RESUMO

BACKGROUND: Lake Baikal is the largest body of liquid freshwater on Earth. Previous studies have described the microbial composition of this habitat, but the viral communities from this ecosystem have not been characterized in detail. RESULTS: Here, we describe the viral diversity of this habitat across depth and seasonal gradients. We discovered 19,475 bona fide viral sequences, which are derived from viruses predicted to infect abundant and ecologically important taxa that reside in Lake Baikal, such as Nitrospirota, Methylophilaceae, and Crenarchaeota. Diversity analysis revealed significant changes in viral community composition between epipelagic and bathypelagic zones. Analysis of the gene content of individual viral populations allowed us to describe one of the first bacteriophages that infect Nitrospirota, and their extensive repertoire of auxiliary metabolic genes that might enhance carbon fixation through the reductive TCA cycle. We also described bacteriophages of methylotrophic bacteria with the potential to enhance methanol oxidation and the S-adenosyl-L-methionine cycle. CONCLUSIONS: These findings unraveled new ways by which viruses influence the carbon cycle in freshwater ecosystems, namely, by using auxiliary metabolic genes that act upon metabolisms of dark carbon fixation and methylotrophy. Therefore, our results shed light on the processes through which viruses can impact biogeochemical cycles of major ecological relevance. Video Abstract.


Assuntos
Ecossistema , Lagos , Metagenoma/genética , Metagenômica , Vírus/genética , Vírus/metabolismo , Bacteriófagos/classificação , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Bacteriófagos/metabolismo , Ciclo do Carbono/genética , Ciclo do Ácido Cítrico/genética , Genes Virais , Federação Russa , Estações do Ano , Vírus/classificação , Vírus/isolamento & purificação
3.
Sci Rep ; 10(1): 11087, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632142

RESUMO

We analysed the relationship between the chemical complex (concentration of dissolved ions, nutrients, pH) and biological parameters (primary production, biomass of phytoplankton, abundance and activity of bacterial communities) at estuaries of rivers and coastal waters of Southern Baikal during the under-ice period. Correlation network analysis revealed CO2 to be the main limiting factor for the development of algae and microbial communities in the coastal zone of Lake Baikal. This study indicates that primarily reverse synthesis of bicarbonate and carbonate ions associated with the development of phytoplankton and accumulation of dissolved CO2 during photosynthesis regulates pH in the Baikal water. We did not detect the anthropogenic factors that influence the change in pH and acidification. Near the Listvyanka settlement (Lake Baikal, Listvennichnaya Bay), there was a great number of organotrophs and thermotolerant bacteria with low bacterioplankton activity and high concentration of organic carbon. This evidences eutrophication due to the influx of organic matter having an anthropogenic source. Nutrients produced during the bacterial destruction of this matter may explain the changes in bottom phytocenoses of Listvennichnaya Bay.

4.
Sci Rep ; 9(1): 19361, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852934

RESUMO

This paper provides a novel report of methane hydrates rising from bottom sediments to the surface of Lake Baikal, validated by photo and video records. The ascent of hydrates in the water column was confirmed by hydroacoustic data showing rising objects with velocities significantly exceeding the typical speeds (18-25 cm s-1) of gas bubbles. Mathematical modelling along with velocity and depth estimates of the presumed methane hydrates coincided with values observed from echograms. Modelling results also showed that a methane hydrate fragment with initial radius of 2.5 cm or greater could reach the surface of Lake Baikal given summer water column temperature conditions. Results further show that while methane bubbles released from the deep sedimentary reservoir would dissolve in the Lake Baikal water column, transport in hydrate form is not only viable but may represent a previously overlooked source of surface methane with subsequent emissions to the atmosphere. Methane hydrates captured within the ice cover may also cause the formation of unique ice structures and morphologies observed around Lake Baikal. Sampling of these ice structures detected methane content that exceeded concentrations measured in surrounding ice and from the atmosphere demonstrating a link with the methane transport processes described here.

5.
Vopr Onkol ; 61(3): 430-4, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26242157

RESUMO

There are presented results of photodynamic therapy (PDT) for patients with chemo- and radioresistant intradermal metastases of breast cancer using the matrix light-emitting diodes apparatus. To all patients prior to irradiation there was performed fluorescence diagnostics to assess the accumulation of the photosensitizer of chlorine series and photobleaching during PDT. The size of the irradiation area was 400 sm, the total dose of irradiation was 250J/cm2. PDT was accompanied by mild pain, which was stopped by administration of non-narcotic analgesics. Complete regression of intradermal lesions was registered in 2 of 4 cases, partial response was observed in 1 patient and the progression of the process in 1 case.


Assuntos
Neoplasias da Mama/patologia , Fotoquimioterapia/instrumentação , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/secundário , Feminino , Humanos , Pessoa de Meia-Idade , Fotoquimioterapia/métodos , Resultado do Tratamento
6.
Vopr Onkol ; 61(3): 460-6, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26242162

RESUMO

The work is devoted to the methods of application of own adipose tissue as a plastic material and presents the summary of the currently known data on the use of transplantation of adipose tissue in order to correct various defects of the body in plastic and reconstructive surgery. There are analyzed theoretical basis for the use of adipose tissue, provided the methods of administration depending on the area of the use, the severity of the defect and its localization. Data on new methods of the use of adipose tissue and own observations are presented. As an example of the effective use there is provided a detailed analysis of the use of adipose tissue transplantation in breast cancer patients who have different area defects after reconstructive surgery.


Assuntos
Tecido Adiposo/transplante , Neoplasias da Mama/cirurgia , Mamoplastia/métodos , Adulto , Feminino , Humanos , Microcirurgia , Procedimentos de Cirurgia Plástica/métodos , Transplante Autólogo , Resultado do Tratamento
7.
Mikrobiologiia ; 84(1): 98-106, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25916152

RESUMO

Microbiological and biogeochemical investigation of the water column of oligotrophic Lake Baikal at the sites of the K2 and Bolshoy mud volcanoes and the Gorevoy Utes oil seep was carried out in July 2013. Total microbial numbers (TMN), cell numbers of type I and type II methanotrophs, and methane concentrations were measured; the rate of methane oxidation was determined. Methane concentrations in Lake Baikal water column varied from 0.09 to 1 µL/L, while methane oxidation rates varied from 0.007 to 0.9 nL/(L day). The highest rates of methane oxidation were revealed in the near-bottom water horizons at the sites of the Bolshoy mud volcano and the Gorevoy Utes oil seep. These were the sites where the most pronounced anomalies in methane concentration were also detected. TMN varied from 0.123 x 10(6) to 1.64 x 10(6) cells/mL. Methanotrophic bacteria were revealed in the water column at all sites, their abundance did not always correlate with methane concentrationsand the rates of methane oxidation. Methanotrophs constituted not more than 1.63% of the total microbial number, with their highest abundance in the upper 200 m of the water column.


Assuntos
DNA Bacteriano/análise , Lagos/microbiologia , Methylobacteriaceae/genética , Campos de Petróleo e Gás/microbiologia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Hibridização in Situ Fluorescente , Lagos/química , Metano/química , Metano/metabolismo , Methylobacteriaceae/classificação , Campos de Petróleo e Gás/química , Oxirredução , Sibéria
8.
Mikrobiologiia ; 83(6): 694-702, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25941719

RESUMO

Production of gaseous hydrocarbons by the microbial community of the Posolsky Bank methane seep bottom sediments (Southern Baikal) was studied at 4°C. Formation of both methane and a heavier gas- eous hydrocarbon, ethane, was detected in enrichment cultures. The highest methane concentrations (6.15 and 4.51 mmol L(-1)) were revealed in enrichments from the sediments from 55-cm depth incubated with-so- dium acetate and H2/CO2 gas mixture, respectively. A decrease in activity of aceticlastic methanogensand a decrease in methane concentration produced by hydrogenotrophic archaea occurred with depth. The highest concentration of ethane was revealed in enrichments from the microbial community of the layer close to gas hydrates (75 cm) incubated with CO2 as a substrate. According to analysis of the 16S rRNA gene fragments from the clone library, these enrichments were found to contain members of the phylum Crenarchaeota form- ing a separate cluster with members of the class Thermoprotei. The phylum Euryarchaeota was represented by nucleotide sequences of the organisms homologous to members of the orders Methanococcales, Methanosa- rcinales, and Thermoplasmatales.


Assuntos
Archaea/metabolismo , Sedimentos Geológicos/microbiologia , Hidrocarbonetos/metabolismo , Filogenia , Archaea/genética , Dióxido de Carbono/metabolismo , Crenarchaeota/genética , Crenarchaeota/isolamento & purificação , Crenarchaeota/metabolismo , Etano/metabolismo , Euryarchaeota/genética , Euryarchaeota/isolamento & purificação , Euryarchaeota/metabolismo , Biblioteca Gênica , Lagos , Metano/metabolismo , Consórcios Microbianos , Dados de Sequência Molecular , RNA Ribossômico 16S , Sibéria
9.
Vestn Khir Im I I Grek ; 172(3): 76-9, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24340978

RESUMO

The oncological breast surgeries with single-stage replacement of the lost volume by means of autogeneous tissue using distant flaps grafting (particularly by skin--muscular flaps of the latissimus dorsi) allow obtaining satisfactory and stable aesthetic results without the decrease of indices of relapse-free and general survival. The early results of the application of the skin-muscular flaps of the latissimus dorsi for single-stage breast reconstruction after radical breast resection are presented in this work in 3 patients with breast cancer. The technique allows performance of the extensive radical resection with single-stage grafting in patients with breast cancer and obtaining an objective clinical response against the background of neoadjuvant therapy with subsequent applying radiation therapy and systemic treatment.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia/métodos , Satisfação do Paciente , Transplante de Pele/métodos , Músculos Superficiais do Dorso/transplante , Retalhos Cirúrgicos , Adulto , Feminino , Seguimentos , Humanos , Mastectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
10.
Vopr Onkol ; 59(3): 363-7, 2013.
Artigo em Russo | MEDLINE | ID: mdl-23909039

RESUMO

The absolute sensitivity signs of breast cancer to the drug have not yet been developed. Data from clinical trials on the study of experimental laboratory predictive markers of chemosensitivity: TOP2alpha (topoisomerase 2-alpha), beta-tubulin (subunit of dimeric protein tubulin), and BRCA1 (breast cancer 1) are contradictory and not numerous. Analysis of the results by the end of the clinical trial will allow examining the correlation between the effectiveness of preoperative taxane-chemotherapy and the level of experimental and standard molecular markets that is important for development of algorithm of treatment tactics for patients with locally advanced breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Adulto , Idoso , Antígenos de Neoplasias/análise , Neoplasias da Mama/química , Neoplasias da Mama/cirurgia , DNA Topoisomerases Tipo II/análise , Proteínas de Ligação a DNA/análise , Esquema de Medicação , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pré-Operatório , Taxoides/administração & dosagem , Resultado do Tratamento , Tubulina (Proteína)/análise
11.
Adv Gerontol ; 26(3): 469-71, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24640695

RESUMO

Data results of treatment of elderly breast cancer patients in different medical centers are provided, cohort up to 1922 patients. Better survival indicators are recorded within this category when using standard treatment plans (the same as for main category of patients). However it has been noticed that in most cases the patients' age (70-80 years) was considered a barrier to prescription the adequate treatment; 54-98% of patients do not receive standard treatment.


Assuntos
Neoplasias da Mama/terapia , Fidelidade a Diretrizes , Guias de Prática Clínica como Assunto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/métodos , Terapia Combinada/normas , Feminino , Humanos
12.
J Phys Condens Matter ; 24(17): 175404, 2012 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-22475790

RESUMO

The structural data and Raman spectra of distorted R(3+)B(3+)O(3) perovskites (R(3+)-rare earth, B(3+)=Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Ga) with BO(6) octahedral tilts were critically reviewed in order to obtain the frequency (ω) versus BO(6) tilt angle (α) dependence of the quasi-soft vibrational modes. It was found that the relation ω = Ï°α is satisfied in a good approximation for each RBO(3) family with fixed B atom, despite the different spatial tilt orientations for compounds of the same series with either orthorhombic Pnma or rhombohedral R ̅3c structure. The dependence of the proportionality coefficient Ï° on the averaged octahedral distance can be described using different functions (power, linear and exponential ones). The established dependences can be used for analysis of Raman data and heuristic prediction of structural second-order transitions.


Assuntos
Compostos de Cálcio/química , Complexos de Coordenação/química , Ferro/química , Metais Terras Raras/química , Óxidos/química , Análise Espectral Raman/métodos , Titânio/química , Boro/química , Cristalografia por Raios X , Modelos Moleculares , Modelos Estatísticos , Conformação Molecular , Oxigênio/química , Reprodutibilidade dos Testes , Temperatura , Vibração
15.
Vopr Onkol ; 57(5): 672-4, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22238942
16.
Vopr Onkol ; 56(4): 417-23, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20968020

RESUMO

Our study was concerned with evaluation of patterns of lymph flow from primary breast cancer. Radionuclide scintigraphy (RS) of lymph nodes was performed in 92 patients. Scinitigraphic images were obtained 30-60 and 240-360 min after intratumoral injection of 75-150 MBq (0,5-1 vl) of 99mTc nanocolloids. The pool sites of the radiodrug collection were as follows: axillary (Ax), sub-supraclavicular (SSCL) and internal mammary (IM). Imaging proved effective in 86 cases. No drug transport was recorded in 5 cases; 4 of them revealed macroscopic metaststases to the lymph nodes. External involvement of the axillary lymph nodes was visualized in 51 patients out of 52 while in 26 it occurred on the axillary site only. In another 25 patients, images of lymph nodes were obtained on 2 or 3 sites: drainage Ax+SSCL (12;23.1%), Ax+IM (6;11.6%) and Ax+SSCL+IM (7;13.4%). In patients with tumors in internal quadrants (34), the lymph flow patterns were as follows: Ax (12;35.3%), IM (2;5.8%), Ax+SSCL (8;23.5%), Ax+IM+SSCL (5;14.7%). Hence, the efficacy of lymph node visualization after intratumoral injection of nanocolloids was 98%. Visualization on Ax sites was further confirmed by lymph flow to SSCL and IM (29.1%) and (35.9%), respectively. The likelihood of lymph flow to IM is significantly higher in patients with internal localization of breast cancer (37.1%) but it is not negligible (22.9%) in cases of external quadrants.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Vasos Linfáticos/diagnóstico por imagem , Adulto , Idoso , Axila , Feminino , Humanos , Metástase Linfática/diagnóstico por imagem , Pessoa de Meia-Idade , Cintilografia , Agregado de Albumina Marcado com Tecnécio Tc 99m
18.
Mikrobiologiia ; 77(5): 660-7, 2008.
Artigo em Russo | MEDLINE | ID: mdl-19004348

RESUMO

The microbial communities of the estuarine zone and the mixing zone of river and lake waters in the Selenga River estuary were studied using the fluorescence in situ hybridization (FISH) method. The microorganisms belonging to the phylogenetic group Gammaproteobacteria were found to predominate in the river estuary, constituting up to 17% of the total bacterial community. Among cultivable microorganisms, organotrophic bacteria were predominant (2040 CFU/ml) in this zone, which results in high rates of microbial production (6.0 microg C/(1 day). The microbial community structure changed with distance from the river estuary; representatives of the Alpha-, Beta-, and Gammaproteobacteria were present in equal proportions; psychrotolerant and oligotrophic bacteria were numerous. The rate of heterotrophic carbon dioxide assimilation decreased to 3.8 microg C/(1 day). At 5-7 km from the river estuary, where the hydrologic, physical, and chemical conditions are similar to those of lake waters, members of the Betaproteobacteria, which are typical of the open waters of Lake Baikal, are the major representatives of planktonic microorganisms.


Assuntos
Alphaproteobacteria/classificação , Betaproteobacteria/classificação , Gammaproteobacteria/classificação , Rios/microbiologia , Microbiologia da Água , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Betaproteobacteria/genética , Betaproteobacteria/isolamento & purificação , Dióxido de Carbono/metabolismo , Contagem de Colônia Microbiana , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Hibridização in Situ Fluorescente , Rios/química , Sibéria
19.
Vopr Onkol ; 53(4): 400-8, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17969401

RESUMO

Data are presented on a randomized study (stage II) which was undertaken to assess the efficacy of neoadjuvant chemotherapy (doxorubicin+paclitaxel) vis-a-vis endocrine therapy with aromatase inhibitors (anastrazole or exemestane) in postmenopausal women with ER-positive and/or PgR-positive tumors. Preoperative neoadjuvant chemotherapy was well tolerated and showed similar rates of overall response as compared with the latter regimen.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Neoadjuvante/métodos , Idoso , Idoso de 80 Anos ou mais , Anastrozol , Androstadienos/administração & dosagem , Neoplasias da Mama/química , Neoplasias da Mama/diagnóstico por imagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Paclitaxel/administração & dosagem , Pós-Menopausa , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Resultado do Tratamento , Triazóis/administração & dosagem
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