305 research outputs found
FEATURES OF GENOTYPiNG VARIABILITY OF STRAINS OF BORDETELLA PERTUSSIS ALLOCATED FROM PATIENTS WITH WHOOPING COUGH IN RUSSIA
On the basis of studying of features of structure of 7 genes determining major factors of pathogenicity of the causative agent of whooping cough - ptxA, ptxB, ptxC, ptxD, ptxE, ptxP and prn, features of genotyping variability of strains of B.pertussis allocated from patients with whooping cough in Russia are shown. Dynamics of formation of population of strains of the causative agent of whooping cough is tracked and is established that population of strains of B.pertussis is formed by clonal expansion of strains with, new genetic structure of major factors of pathogenicity - pertussis toxin and. pertactin. The structure of population of strains of B.pertussis causing a disease by whooping cough, at the present stage of epidemic process of a pertussis infection - domination. of strains with new «non-vaccine» alleles genes - ptxA1 (97,7 %), ptxC2 (87,4 %), prn2 (89,5 %) and. ptxP3 (93,3 %), in 2,2 % cases with ptxB2 allele and. in 1,3 % cases with. prn9 allele circulate
MODERN STATUS OF VACCINE PROPHYLAXIS OF MUMPS
Abstract. Vaccination against mumps is conducted in Russian Federation since 1981. This made it possible to decrease mumps incidence more than 600 times in compare with pre-vaccination period. Moreover disease became milder and mortality was eliminated. Population of Russia is immunized by locally-produced mono- and bivalent vaccines on the base of L3 strain. Vaccination and revaccination against mumps is safe and highly effective
SPECIFIC TRAITS OF TICK-BORNE ENCEPHALITIS IN ZABAYKALSKY KRAI
We conducted regionalization of Zabaykalsky Krai by the quantity of epidemic manifestations of tick-borne viral encephalitis over a period of 10years. The most adverse territories in the context of tick-borne viral encephalitis were determined. Maximum duration of seasonal incidence rate was 112 days -from the end of April to the mid-August. The categories of population included in infection contamination risk group were revealed. The researches promote forehanded development of the complex of preventive measures aimed at the decrease of tick- borne viral encephalitis incidence rate in Zabaykalsky Krai
Bioaugmentation with copper tolerant endophyte Pseudomonas lurida strain EOO26 for improved plant growth and copper phytoremediation by Helianthus annuus
Organic fertilizers became a better alternative to chemical fertilizers in modern agricultural practices however, contamination of copper (Cu) from organic fertilizer is still a major concern for the globe. Plant growth promoting (PGP) microorganisms showed their efficiency to combat with this problem and thus Cu tolerant PGP endophytes from roots of Odontarrhena obovata (Alyssum obovatum) growing on Cu smelter contaminated serpentine soil were explored in present study. Out of twenty-four isolates, Pseudomonas lurida strain EOO26 identified by 16s rRNA gene sequencing was selected to check its efficacy for Cu-remediation. The strain EOO26 showed multi-metal tolerance, drought resistance and exhibited PGP attributes such as 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, siderophore and ammonia production. Significant production of indole-3-acetic acid and phosphate-solubilization under different Cu concentration (0–100 mg L−1) at varying pH (5.0–8.0) suggests potentiality of this strain to work effectively under wide range of abiotic stress conditions. Plant growth experiment (pH 6.8 ± 0.3) in copper spiked soil suggested a significant increase in length and dry weight of root and shoot of sunflower (Helianthus annuus) after inoculation with strain EOO26. Plants inoculated with strain EOO26 resulted in increase in Cu uptake by 8.6-fold for roots and 1.9-fold for leaves than uninoculated plants. The total plant uptake in inoculated Cu treatment was 2.6-fold higher than uninoculated one, which is much higher than the previously reported Cu accumulating plants. The excellent adaptation abilities and promising metal removal efficiency strongly indicate superiority of strain EOO26 for phytoremediation of Cu-contamination and may work effectively for Cu removal from contaminated soils. © 2020 Elsevier LtdScience and Engineering Research Board, SERB; Department of Science and Technology, Government of West Bengal, DST: INT/ RUS / RFBR /363; Ministry of Science and Higher Education of the Russian FederationThe authors acknowledge the work support by RFBR , Russia (Project No. 19-516-45006) and DST , India (INT/ RUS / RFBR /363) and the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 02.A03.21.0006). L.B.B thankful to the Science and Engineering Research Board (SERB), India for providing National Post-Doctoral Fellowship (Grant No. PDF/2017/001074 )
Холодный эпизод около 8200 лет назад в Северной Европе: анализ эмпирических данных и возможных причин
Cold episode in Northern Europe happened about 8200 years ago was known for a relatively long time, mainly due to paleobotanical (palynological) data obtained from analysis of lake and peat sediments. Detailed analysis of ice cores from the Greenland holes GRIP, GISP2, and NGRIP with a time resolution of about 10 years made possible to refine the duration and characteristics of the time structure of this cold period. This cooling lasted for approximately 160 yr. Spore-pollen analysis of lake sediments in Northern Europe (Sweden, Finland, Denmark, Germany, the North and North-West of Russia) and deep-sea cores of the North Atlantic showed that the mean annual air temperature during the maximum stage of the cooling was reduced by 1–2 °C, and in some areas by more than 3 °C. The cold spread from the coast of the North Atlantic into the European continent and manifested itself mostly in Sweden, Finland, the Baltic States, and to a lesser extent in the North-West and West of the Russian Federation. In the central Russia and North of 70°N the cooling was weak or absent. The question about a nature of this cold event and other cold spells in Late Glaciation, known as the cold of the early, middle and late Dryas, is widely discussed in the scientific literature. Most of scientists accept a hypothesis proposed more than 20 years ago, that the reduction of air temperatures in regions immediately adjacent to the North Atlantic was caused by the large volume of melt water discharged into the ocean as a result of disintegration and melting of ice-sheets. Climate models that take into account these effects allow estimating a decrease in the air and sea surface temperature due to freshening (desalination) of the upper ocean layer, and this confirms that the greatest decrease in temperature should be observed in the regions directly adjacent to the ocean. The increase in global temperature over the last 30 years is estimated to be 0.8 ± 0.2 °C, which is already reflected in a noticeable increase in precipitation in high latitudes. In addition, the melting of mountain glaciers and sea ice in the Arctic basin promotes freshening of the upper ocean, and as a result of these processes one can expect a certain decrease in the air temperature in the high latitudes if the present-day climate warming will continue. On the basis of paleoclimatic data, it can be assumed that such a decrease in air temperature can be relatively small and occur only in areas directly adjacent to the North Atlantic.Уже более 20 лет в Северной Европе известен холодный эпизод около 8200 лет назад. Похолодание продолжалось около 160 лет, температуры воздуха снижались на 1–2 °С, а в отдельных районах – более чем на 3 °С. Предполагается, что снижение температур воздуха было связано с поступлением больших объёмов пресной воды в Северную Атлантику в результате распада и таяния ледников. Подобный механизм имеет прямое отношение к оценкам будущего климата при развитии современного глобального потепления. Поскольку таяние горных ледников и морских льдов в Полярном бассейне способствует опреснению верхнего слоя океана, при развитии потепления в районах, непосредственно прилегающих к Северной Атлантике, можно ожидать некоторого снижения температуры воздуха в высоких широтах
Observational Diagnostics of Gas Flows: Insights from Cosmological Simulations
Galactic accretion interacts in complex ways with gaseous halos, including
galactic winds. As a result, observational diagnostics typically probe a range
of intertwined physical phenomena. Because of this complexity, cosmological
hydrodynamic simulations have played a key role in developing observational
diagnostics of galactic accretion. In this chapter, we review the status of
different observational diagnostics of circumgalactic gas flows, in both
absorption (galaxy pair and down-the-barrel observations in neutral hydrogen
and metals; kinematic and azimuthal angle diagnostics; the cosmological column
density distribution; and metallicity) and emission (Lya; UV metal lines; and
diffuse X-rays). We conclude that there is no simple and robust way to identify
galactic accretion in individual measurements. Rather, progress in testing
galactic accretion models is likely to come from systematic, statistical
comparisons of simulation predictions with observations. We discuss specific
areas where progress is likely to be particularly fruitful over the next few
years.Comment: Invited review to appear in Gas Accretion onto Galaxies, Astrophysics
and Space Science Library, eds. A. J. Fox & R. Dave, to be published by
Springer. Typos correcte
Gas Accretion and Star Formation Rates
Cosmological numerical simulations of galaxy evolution show that accretion of
metal-poor gas from the cosmic web drives the star formation in galaxy disks.
Unfortunately, the observational support for this theoretical prediction is
still indirect, and modeling and analysis are required to identify hints as
actual signs of star-formation feeding from metal-poor gas accretion. Thus, a
meticulous interpretation of the observations is crucial, and this
observational review begins with a simple theoretical description of the
physical process and the key ingredients it involves, including the properties
of the accreted gas and of the star-formation that it induces. A number of
observations pointing out the connection between metal-poor gas accretion and
star-formation are analyzed, specifically, the short gas consumption time-scale
compared to the age of the stellar populations, the fundamental metallicity
relationship, the relationship between disk morphology and gas metallicity, the
existence of metallicity drops in starbursts of star-forming galaxies, the
so-called G dwarf problem, the existence of a minimum metallicity for the
star-forming gas in the local universe, the origin of the alpha-enhanced gas
forming stars in the local universe, the metallicity of the quiescent BCDs, and
the direct measurements of gas accretion onto galaxies. A final section
discusses intrinsic difficulties to obtain direct observational evidence, and
points out alternative observational pathways to further consolidate the
current ideas.Comment: Invited review to appear in Gas Accretion onto Galaxies, Astrophysics
and Space Science Library, eds. A. J. Fox & R. Dav\'e, to be published by
Springe
Differential Expression of Type III Effector BteA Protein Due to IS481 Insertion in Bordetella pertussis
BACKGROUND: Bordetella pertussis is the primary etiologic agent of the disease pertussis. Universal immunization programs have contributed to a significant reduction in morbidity and mortality of pertussis; however, incidence of the disease, especially in adolescents and adults, has increased in several countries despite high vaccination coverage. During the last three decades, strains of Bordetella pertussis in circulation have shifted from the vaccine-type to the nonvaccine-type in many countries. A comparative proteomic analysis of the strains was performed to identify protein(s) involved in the type shift. METHODOLOGY/PRINCIPAL FINDING: Proteomic analysis identified one differentially expressed protein in the B. pertussis strains: the type III cytotoxic effector protein BteA, which is responsible for host cell death in Bordetella bronchiseptica infections. Immunoblot analysis confirmed the prominent expression of BteA protein in the nonvaccine-type strains but not in the vaccine-type strains. Sequence analysis of the vaccine-type strains revealed an IS481 insertion in the 5' untranslated region of bteA, -136 bp upstream of the bteA start codon. A high level of bteA transcripts from the IS481 promoter was detected in the vaccine-type strains, indicating that the transcript might be an untranslatable form. Furthermore, BteA mutant studies demonstrated that BteA expression in the vaccine-type strains is down-regulated by the IS481 insertion. CONCLUSION/SIGNIFICANCE: The cytotoxic effector BteA protein is expressed at higher levels in B. pertussis nonvaccine-type strains than in vaccine-type strains. This type-dependent expression is due to an insertion of IS481 in B. pertussis clinical strains, suggesting that augmented expression of BteA protein might play a key role in the type shift of B. pertussis
- …