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[Abundance and activity of microorganisms at the water-sediment interface and their effect on the carbon isotopic composition of suspended organic matter and sediments of the Kara Sea].

https://arctichealth.org/en/permalink/ahliterature259299
Source
Mikrobiologiia. 2013 Nov-Dec;82(6):723-31
Publication Type
Article
Author
M V Ivanov
A Iu Lein
A S Savvichev
I I Rusanov
E F Veslopolova
E E Zakharova
T S Prusakova
Source
Mikrobiologiia. 2013 Nov-Dec;82(6):723-31
Language
Russian
Publication Type
Article
Keywords
Arctic Regions
Carbon Isotopes - analysis - metabolism
Methanobacteriales - metabolism
Methanomicrobiales - metabolism
Oceans and Seas
Russia
Water Microbiology
Abstract
At ten stations of the meridian profile in the eastern Kara Sea from the Yenisei estuary through the shallow shelf and further through the St. Anna trough, total microbial numbers (TMN) determined by direct counting, total activity of the microbial community determined by dark CO2 assimilation (DCA), and the carbon isotopic composition of organic matter in suspension and upper sediment horizons (d13C, per thousand) were investigated. Three horizons were studied in detail: (1) the near-bottom water layer (20-30 cm above the sediment); (2) the uppermost, strongly hydrated sediment horizon, further termed warp (5-10 mm); and (3) the upper sediment horizon (1-5 cm). Due to decrease in the amount of isotopically light carbon of terrigenous origin with increasing distance from the Yenisei estuary, the TMN and DCA values decreased, and the d13C changed gradually from -29.7 to -23.9 per thousand. At most stations, a noticeable decrease in TMN and DCA values with depth was observed in the water column, while the carbon isotopic composition of suspended organic matter did not change significantly. Considerable changes of all parameters were detected in the interface zone: TMN and DCA increased in the sediments compared to their values in near-bottom water, while the 13C content increased significantly, with d13C of organic matter in the sediments being at some stations 3.5- 4.0 per thousand higher than in the near-bottom water. Due to insufficient illumination in the near-bottom zone, newly formed isotopically heavy organic matter (d13C(-) -20 per thousand) could not be formed by photosynthesis, active growth of chemoautotrophic microorganisms in this zone is suggested, which may use reduced sulfur, nitrogen, and carbon compounds diffusing from anaerobic sediments. High DCA values for the interface zone samples confirm this hypothesis. Moreover, neutrophilic sulfur-oxidizing bacteria were retrieved from the samples of this zone.
PubMed ID
25509411 View in PubMed
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[Abundance and diversity of methanotrophic Gammaproteobacteria in northern wetlands].

https://arctichealth.org/en/permalink/ahliterature259581
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):204-14
Publication Type
Article
Author
O V Danilova
S N Dedysh
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):204-14
Language
Russian
Publication Type
Article
Keywords
Biodiversity
Fresh Water - microbiology
Gammaproteobacteria - genetics - isolation & purification - metabolism
Hydrogen-Ion Concentration
In Situ Hybridization, Fluorescence
Methane - metabolism
Methylococcaceae - genetics
Methylocystaceae - genetics
Molecular Sequence Data
Oxygenases - genetics
Phylogeny
RNA, Ribosomal, 16S
Russia
Wetlands
Abstract
Numeric abundance, identity and pH preferences of methanotrophic Gammaproteobacteria (type I methanotrophs) inhabiting the northern acidic wetlands were studied. The rates of methane oxidation by peat samples from six-wetlands of European Northern Russia (pH 3.9-4.7) varied from 0.04 to 0.60 µg CH4 g(-1) peat h(-1). The number of cells revealed by hybridization with fluorochrome-labeled probes M84 + M705 specific for type I methanotrophs was 0.05-2.16 x 10(5) cells g(-1) dry peat, i.e. 0.4-12.5% of the total number of methanotrophs and 0.004-0.39% of the total number of bacteria. Analysis of the fragments of the pmoA gene encoding particulate methane monooxygenase revealed predominance of the genus Methylocystis (92% of the clones) in the studied sample of acidic peat, while the proportion of the pmoA sequences of type I methanotrophs was insignificant (8%). PCR amplification of the 16S rRNA gene fragments of type I methanotrophs with TypeIF-Type IR primers had low specificity, since only three sequences out of 53 analyzed belonged to methanotrophs and exhibited 93-99% similarity to those of Methylovulum, Methylomonas, and Methylobacter species. Isolates of type I methanotrophs obtained from peat (strains SH10 and 83A5) were identified as members of the species Methylomonaspaludis and Methylovulum miyakonense, respectively. Only Methylomonaspaludum SH10 was capable of growth in acidic media (pH range for growth 3.8-7.2 with the optimum at pH 5.8-6.2), while Methylovulum miyakonense 83A5 exhibited the typical growth characteristics of neutrophilic methanotrophs (pH range for growth 5.5-8.0 with the optimum at pH 6.5-7.5).
PubMed ID
25423724 View in PubMed
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[A comparative analysis of genomes of virulent and avirulent strains of Vibrio cholerae O139].

https://arctichealth.org/en/permalink/ahliterature179953
Source
Mol Gen Mikrobiol Virusol. 2004;(2):11-6
Publication Type
Article
Date
2004
Author
G A Eroshenko
A V Osin
E Iu Shchelkanova
N I Smirnova
Author Affiliation
Mikrob Russian Research Anti-Plague Institute, Saratov.
Source
Mol Gen Mikrobiol Virusol. 2004;(2):11-6
Date
2004
Language
Russian
Publication Type
Article
Keywords
Adenosine Triphosphatases - genetics
Bacterial Outer Membrane Proteins - genetics
Bacterial Proteins - genetics
Bacterial Toxins - genetics
Cholera - microbiology
Cholera Toxin - genetics
DNA-Binding Proteins - genetics
Genome, Bacterial
Humans
Membrane Glycoproteins
Membrane Proteins - genetics
Proteins - genetics
Russia
Serine Endopeptidases - genetics
Transcription Factors - genetics
Vibrio cholerae O139 - genetics - pathogenicity
Virulence Factors - genetics
Water Microbiology
Abstract
A comparative analysis of the genome of V. cholerae O139 strains isolated in Russia's territory from patients with cholera and from the environment showed essential differences in their structures. The genome of clinical strains possessed all tested genes associated with virulence (ctxAB, zot, ace, rstC, rtxA, hap, toxR and toxT) and the at-tRS site for the CTXp phage DNA integration. As for the O139 V. cholerae chromosome strains isolated from water, 70% of the studied genes (ctxAB, zot, ace, rstC, tcpA, and toxT) and the attRS sequence were not detected in them. A lack of the key virulence genes in O139-serogroup "water" vibrios, including genes of toxin-coregulated adhesion pili. (that are receptors for the CTXp phage), and of the attachment site of the above phage are indicative of that the O139 V. cholerae strains isolated from open water sources located in different Russia's regions are epidemically negligible.
PubMed ID
15164715 View in PubMed
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The activated sludge ecosystem contains a core community of abundant organisms.

https://arctichealth.org/en/permalink/ahliterature275609
Source
ISME J. 2016 Jan;10(1):11-20
Publication Type
Article
Date
Jan-2016
Author
Aaron M Saunders
Mads Albertsen
Jes Vollertsen
Per H Nielsen
Source
ISME J. 2016 Jan;10(1):11-20
Date
Jan-2016
Language
English
Publication Type
Article
Keywords
Bacteria - classification - genetics - growth & development - isolation & purification
Denmark
Ecosystem
RNA, Ribosomal, 16S - genetics
Sewage - microbiology
Waste Water - microbiology
Abstract
Understanding the microbial ecology of a system requires that the observed population dynamics can be linked to their metabolic functions. However, functional characterization is laborious and the choice of organisms should be prioritized to those that are frequently abundant (core) or transiently abundant, which are therefore putatively make the greatest contribution to carbon turnover in the system. We analyzed the microbial communities in 13 Danish wastewater treatment plants with nutrient removal in consecutive years and a single plant periodically over 6 years, using Illumina sequencing of 16S ribosomal RNA amplicons of the V4 region. The plants contained a core community of 63 abundant genus-level operational taxonomic units (OTUs) that made up 68% of the total reads. A core community consisting of abundant OTUs was also observed within the incoming wastewater to three plants. The net growth rate for individual OTUs was quantified using mass balance, and it was found that 10% of the total reads in the activated sludge were from slow or non-growing OTUs, and that their measured abundance was primarily because of immigration with the wastewater. Transiently abundant organisms were also identified. Among them the genus Nitrotoga (class Betaproteobacteria) was the most abundant putative nitrite oxidizer in a number of activated sludge plants, which challenges previous assumptions that Nitrospira (phylum Nitrospirae) are the primary nitrite-oxidizers in activated sludge systems with nutrient removal.
Notes
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PubMed ID
26262816 View in PubMed
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[Activity and structure of the sulfate-reducing bacterial community in the sediments of the southern part of Lake Baikal].

https://arctichealth.org/en/permalink/ahliterature259583
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):180-90
Publication Type
Article
Author
N V Pimenov
E E Zakharova
A L Briukhanov
V A Korneeva
B B Kuznetsov
T P Turova
T V Pogodaeva
G V Kalmychkov
T I Zemskaia
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):180-90
Language
Russian
Publication Type
Article
Keywords
DNA, Bacterial - genetics
Geologic Sediments - microbiology
Lakes - microbiology
Microbial Consortia - physiology
Molecular Sequence Data
Phylogeny
RNA, Ribosomal, 16S
Siberia
Sulfur-Reducing Bacteria - genetics - isolation & purification
Water Microbiology
Abstract
The rates of sulfate reduction (SR) and the diversity of sulfate-reducing bacteria (SRB) were studied in the sediments of the Posol'skaya banka elevation in the southern part of Lake Baikal. SR rates varied from 1.2 to 1641 nmol/(dm3 day), with high rates (> 600 nmol/(dm3 day)) observed at both deep-water stations and in subsurface silts. Integral SR rates calculated for the uppermost 50 cm of the sediments were higher for gas-saturated and gas hydrate-bearing sediments than in those with low methane content. Enrichment SRB cultures were obtained in Widdel medium for freshwater SRB. Analysis of the 16S rRNA gene fragments from clone libraries obtained from the enrichments revealed the presence of SRB belonged to Desulfosporosinus genus, with D. lacus as the most closely related member (capable of sulfate, sulfite, and thiosulfate reduction), as well as members of the order Clostridiales.
PubMed ID
25423722 View in PubMed
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[ACTUAL PROBLEMS OF EPIDEMIOLOGIC CONTROL, LABORATORY DIAGNOSTICS AND PROPHYLAXIS OF CHOLERA IN RUSSIAN FEDERATION].

https://arctichealth.org/en/permalink/ahliterature271672
Source
Zh Mikrobiol Epidemiol Immunobiol. 2016 Jan-Feb;(1):89-101
Publication Type
Article
Author
G G Onischenko
A Yu Popova
V V Kutyrev
N I Smirnova
S A Scherbakova
E A Moskvitina
S V Titova
Source
Zh Mikrobiol Epidemiol Immunobiol. 2016 Jan-Feb;(1):89-101
Language
Russian
Publication Type
Article
Keywords
Bacterial Typing Techniques
Cholera - diagnosis - epidemiology - prevention & control - transmission
Disease Outbreaks
Epidemiological Monitoring
Genotype
Humans
Oligonucleotide Array Sequence Analysis
Phylogeny
Retrospective Studies
Russia - epidemiology
Serogroup
Vibrio cholerae - classification - genetics - isolation & purification - pathogenicity
Water Microbiology
Abstract
Main problems of system of epidemiologic control for cholera active in Russian Federation, as well as laboratory diagnostics and vaccine prophylaxis of this especially dangerous infection, that had emerged in the contemporary period of the ongoing 7th pandemic of cholera, are discussed. Features of the genome of natural strains of Vibrio cholerae of El Tor biovar, that possess a poten- tial epidemic threat, as well as problems, that have emerged during isolation of these strains from samples of water of surface water bodies during their monitoring, are also examined. The main direction of enhancement of the system of epidemiologic control for cholera consist in develop- ment of a new algorithm of differentiation of administrative territories of Russian Federation by types of epidemic manifestations, as well as optimization of monitoring of environment objects. Integration of modern highly informative technologies into practice, as well as development of new generation diagnostic preparations based on DNA-chips and immunechips is necessary to increase effectiveness of the conducted operative and retrospective diagnostics in the contemporary period. Creation of national cholera vaccine, ensuring simultaneous protection from cholera causative agents of both O1 and O139 serogroups, is also required.
PubMed ID
27029123 View in PubMed
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[Acute gastroenteritis. An epidemic related to contaminated drinking water].

https://arctichealth.org/en/permalink/ahliterature234442
Source
Ugeskr Laeger. 1987 Nov 30;149(49):3360-1
Publication Type
Article
Date
Nov-30-1987
Source
Tidsskr Nor Laegeforen. 2007 Aug 9;127(15):1966-8
Publication Type
Article
Date
Aug-9-2007

Advancing infection control in dental care settings: factors associated with dentists' implementation of guidelines from the Centers for Disease Control and Prevention.

https://arctichealth.org/en/permalink/ahliterature120263
Source
J Am Dent Assoc. 2012 Oct;143(10):1127-38
Publication Type
Article
Date
Oct-2012
Author
Jennifer L Cleveland
Arthur J Bonito
Tammy J Corley
Misty Foster
Laurie Barker
G. Gordon Brown
Nancy Lenfestey
Linda Lux
Author Affiliation
Division of Oral Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, MS F-10, 4770 Buford Highway, Atlanta, Ga. 30341, USA. JLCleveland@cdc.gov
Source
J Am Dent Assoc. 2012 Oct;143(10):1127-38
Date
Oct-2012
Language
English
Publication Type
Article
Keywords
Administrative Personnel
Canada
Centers for Disease Control and Prevention (U.S.)
Dental Instruments
Dentist's Practice Patterns - statistics & numerical data
Education, Dental, Continuing
Female
Guideline Adherence
Guidelines as Topic
Health Plan Implementation
Humans
Infection Control, Dental - methods - standards - statistics & numerical data
Male
Middle Aged
Needlestick Injuries - prevention & control
Questionnaires
United States
United States Occupational Safety and Health Administration
Water Microbiology
Abstract
The authors set out to identify factors associated with implementation by U.S. dentists of four practices first recommended in the Centers for Disease Control and Prevention's Guidelines for Infection Control in Dental Health-Care Settings-2003.
In 2008, the authors surveyed a stratified random sample of 6,825 U.S. dentists. The response rate was 49 percent. The authors gathered data regarding dentists' demographic and practice characteristics, attitudes toward infection control, sources of instruction regarding the guidelines and knowledge about the need to use sterile water for surgical procedures. Then they assessed the impact of those factors on the implementation of four recommendations: having an infection control coordinator, maintaining dental unit water quality, documenting percutaneous injuries and using safer medical devices, such as safer syringes and scalpels. The authors conducted bivariate analyses and proportional odds modeling.
Responding dentists in 34 percent of practices had implemented none or one of the four recommendations, 40 percent had implemented two of the recommendations and 26 percent had implemented three or four of the recommendations. The likelihood of implementation was higher among dentists who acknowledged the importance of infection control, had practiced dentistry for less than 30 years, had received more continuing dental education credits in infection control, correctly identified more surgical procedures that require the use of sterile water, worked in larger practices and had at least three sources of instruction regarding the guidelines. Dentists with practices in the South Atlantic, Middle Atlantic or East South Central U.S. Census divisions were less likely to have complied.
Implementation of the four recommendations varied among U.S. dentists. Strategies targeted at raising awareness of the importance of infection control, increasing continuing education requirements and developing multiple modes of instruction may increase implementation of current and future Centers for Disease Control and Prevention guidelines.
Notes
Erratum In: J Am Dent Assoc. 2012 Dec;143(12):1289
PubMed ID
23024311 View in PubMed
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786 records – page 1 of 79.