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Social distancing as altruism in the context of the coronavirus pandemic: A cross-cultural study
No full text11 March 2020. COVID-19 is declared a pandemic. The era of “social distance” has come, characterized as minimizing contacts between people and maintaining the one-to-two meter distance between individuals. Reduction of interpersonal contacts and increased social distance are part of behavioural adaptation to epidemics in the human evolution. In this article we consider social distance as an act of altruism toward fellow citizens. The society found itself facing a moral dilemma – COVID-19 poses little risk to healthy persons, while social distance and isolation impose limits on everyone. The benefits of keeping precautionary measures in place are vital for the groups most at risk, and the community as a whole benefits greatly by reducing the likelihood of a large-scale outbreak. This study was conducted among Russian-speaking respondents living or staying in various countries, as well as in Russia, at the time of the outbreak and spread of the coronavirus. We used a set of methods: semi-structured in-depth interview, questionnaires, the “snowball” method, photographing elements of people’s behaviour during the pandemic, as well as content analysis of news stories in the media. A total of 371 profiles (48 men and 323 women) from 33 countries were collected. Our data show that individual behaviour in the context of the COVID-19 pandemic is influenced by factors such as country of residence, sex, level of stress, trust in authorities, awareness of the prescribed rules of behaviour, cultural norms, and traditions. Moreover, these factors affect both the perception of the situation and the implementation of the authorities’ recommendations. © 2020 Tomsk State University. All rights reserved
Assessment of Population Immunity to SARS-CoV-2 Virus in the Rostov Region
No full textВ Российской Федерации к августу 2020 г. подтверждено более 850 тыс. случаев заболевания новой коронавирусной инфекцией (COVID-19), вызванной SARS-CoV-2. Ростовская область вошла в число десяти наиболее пораженных регионов России. Распространение болезни во многом определяется состоянием популяционного иммунитета на определенной территории.
Целью настоящего исследования являлись изучение специфического гуморального иммунного ответа и оценка уровня популяционного иммунитета к вирусу SARS-CoV-2 среди населения Ростовской области.
Материалы и методы. В исследовании приняли участие 3048 человек. Волонтеры распределялись по семи возрастным группам. Содержание антител к SARS-CoV-2 определяли методом ИФА с использованием набора для анализа сыворотки или плазмы крови человека на наличие специфических IgG к нуклеокапсиду вируса SARS-CoV-2 производства Государственного научного центра прикладной микробиологии и биотехнологии (Оболенск) в соответствии с инструкцией по применению.
Результаты и обсуждение. Проведенная оценка серопревалентности к SARS-CoV-2 жителей Ростовской области показала, что доля лиц с положительными результатами теста на антитела IgG к новому коронавирусу составила 16,5 %, доля серопозитивных лиц в генеральной совокупности находится в пределах от 13,9 до 19,1 % (
Comparative genomics and drug resistance of a geographic variant of ST239 methicillin-resistant Staphylococcus aureus emerged in Russia
No full textTwo distinct classes of methicillin-resistant Staphylococcus aureus (MRSA) are spreading in hospitals (as hospital-acquired MRSA, HA-MRSA) and in the community (as community-acquired MRSA, CA-MRSA). Multilocus sequence type (ST) 239 MRSA, one of the most worldwide-disseminated lineages, has been noted as a representative HA-MRSA. Here, we isolated ST239 MRSA (spa type 3 [t037] and staphylococcal cassette chromosome mec [SCCmec] type III.1.1.1) and its novel variant with ST239/spa351 (t030)/SCCmecIII.1.1.4 (SCCmecIII R) not only from hospitals but also from patients with urethritis in the community in Russia. The Russian variant (strain 16K) possessed a hybrid genome consisting of CC8 and CC30, similar to the ST239/spa3/SCCmecIII.1.1.1 HA-MRSA (TW20) genome, but with marked diversity. The 16K′ CC30 section had SCCmecIII R carrying the dcs-carrying unit (which corresponded to the SCCmecIVc J3 joining region of ST30 CA-MRSA), lacked SCCmercury, and possessed a novel mobile element structure (MES16K) carrying the ccrC-carrying unit (with the recombinase gene ccrC1 allele 3) and drug resistance tranposons. The Russian variant included strains with a high ability to transfer its multiple drug resistance by conjugation; e.g., for strain 16K, the transfer frequency of a chloramphenicol resistance plasmid (p16K-1 with 2.9 kb in size) reached 1.4×10 -2, followed by Tn554 conjugative transfer at 3.6×l0 -4. The Russian variant, which has been increasing recently, included divergent strains with different plasmid patterns and pulsed field gel electrophoresis profiles. The data demonstrate the alternative nature of ST239 MRSA as CA-MRSA and also as a drug resistance disseminator, and its micro but dynamic evolution in Russia. © 2012 Yamamoto et al
Universal oligonucleotide microarray for sub-typing of Influenza A virus
No full textA universal microchip was developed for genotyping Influenza A viruses. It contains two sets of oligonucleotide probes allowing viruses to be classified by the subtypes of hemagglutinin (H1-H13, H15, H16) and neuraminidase (N1-N9). Additional sets of probes are used to detect H1N1 swine influenza viruses. Selection of probes was done in two steps. Initially, amino acid sequences specific to each subtype were identified, and then the most specific and representative oligonucleotide probes were selected. Overall, between 19 and 24 probes were used to identify each subtype of hemagglutinin (HA) and neuraminidase (NA). Genotyping included preparation of fluorescently labeled PCR amplicons of influenza virus cDNA and their hybridization to microarrays of specific oligonucleotide probes. Out of 40 samples tested, 36 unambiguously identified HA and NA subtypes of Influenza A virus
Oseltamivir-ribavirin combination therapy for highly pathogenic H5N1 influenza virus infection in mice
No full textWe studied the effects of a neuraminidase inhibitor (oseltamivir) and an inhibitor of influenza virus polymerases (ribavirin) against two highly pathogenic H5N1 influenza viruses. In vitro, A/Vietnam/1203/04 virus (clade 1) was highly susceptible to oseltamivir carboxylate (50% inhibitory concentration [IC50] = 0.3 nM), whereas A/Turkey/15/06 virus (clade 2.2) had reduced susceptibility (IC50 = 5.5 nM). In vivo, BALB/c mice were treated with oseltamivir (1, 10, 50, or 100 mg/kg of body weight/day), ribavirin (37.5, 55, or 75 mg/kg/day), or the combination of both drugs for 8 days, starting 4 h before virus inoculation. Monotherapy produced a dose-dependent antiviral effect against the two H5N1 viruses in vivo. Three-dimensional analysis of the drug-drug interactions revealed that oseltamivir and ribavirin interacted principally in an additive manner, with several exceptions of marginal synergy or marginal antagonism at some concentrations. The combination of ribavirin at 37.5 mg/kg/day and oseltamivir at 1 mg/kg/day and the combination of ribavirin at 37.5 mg/kg/day and oseltamivir at 10 mg/kg/day were synergistic against A/Vietnam/1203/04 and A/Turkey/15/06 viruses, respectively. These optimal oseltamivir-ribavirin combinations significantly inhibited virus replication in mouse organs, prevented the spread of H5N1 viruses beyond the respiratory tract, and abrogated the cytokine response (P < 0.01). Importantly, we observed clear differences between the efficacies of the drug combinations against two H5N1 viruses: higher doses were required for the protection of mice against A/Turkey/15/06 virus than for the protection of mice against A/Vietnam/1203/04 virus. Our preliminary results suggest that oseltamivir-ribavirin combinations can have a greater or lesser antiviral effect than monotherapy, depending on the H5N1 virus and the concentrations used. Copyright © 2008, American Society for Microbiology. All Rights Reserved
Experimental infection of H5N1 HPAI in BALB/c mice
No full textBackground. In 2005 huge epizooty of H5N1 HPAI occurred in Russia. It had been clear that territory of Russia becoming endemic for H5N1 HPAI. In 2006 several outbreaks have occurred. To develop new vaccines and antiviral therapies, animal models had to be investigated. We choose highly pathogenic strain for these studies. Results. A/duck/Tuva/01/06 belongs to Quinghai-like group viruses. Molecular markers - cleavage site, K627 in PB2 characterize this virus as highly pathogenic. This data was confirmed by direct pathogenic tests: IVPI = 3.0, MLD50= 1,4Log10EID50. Also molecular analysis showed sensivity of the virus to adamantanes and neuraminidase inhibitors. Serological analysis showed wide cross-reactivity of this virus with sera produced to H5N1 HPAI viruses isolated earlier in South-East Asia. Mean time to death of infected animals was 8,19+/-0,18 days. First time acute delayed hemorrhagic syndrome was observed in mice lethal model. Hypercytokinemia was determined by elevated sera levels of IFN-gamma, IL-6, IL-10. Conclusion. Assuming all obtained data we can conclude that basic model parameters were characterized and virus A/duck/Tuva/01/06 can be used to evaluate anti-influenza vaccines and therapeutics. © 2007 Evseenko et al; licensee BioMed Central Ltd
From structure of the complex to understanding of the biology
No full textThe most extensive structural information on viruses relates to apparently icosahedral virions and is based on X-ray crystallography and on cryo-electron microscopy (cryo-EM) single-particle reconstructions. Both techniques lean heavily on imposing icosahedral symmetry, thereby obscuring any deviation from the assumed symmetry. However, tailed bacteriophages have icosahedral or prolate icosahedral heads that have one obvious unique vertex where the genome can enter for DNA packaging and exit when infecting a host cell. The presence of the tail allows cryo-EM reconstructions in which the special vertex is used to orient the head in a unique manner. Some very large dsDNA icosahedral viruses also develop special vertices thought to be required for infecting host cells. Similarly, preliminary cryo-EM data for the small ssDNA canine parvovirus complexed with receptor suggests that these viruses, previously considered to be accurately icosahedral, might have some asymmetric properties that generate one preferred receptor-binding site on the viral surface. Comparisons are made between rhinoviruses that bind receptor molecules uniformly to all 60 equivalent binding sites, canine parvovirus, which appears to have a preferred receptor-binding site, and bacteriophage T4, which gains major biological advantages on account of its unique vertex and tail organelle. © International Union of Crystallography 2007
Shikimic acid: Review of its analytical, isolation, and purification techniques from plant and microbial sources
No full textShikimic acid properties and its available analytical techniques are discussed. Plants having the highest content of shikimic acid are shown. The existing isolation methods are analyzed and the most optimal approaches to extracting this acid from natural sources (plants and microorganisms) are considered. © Springer-Verlag 2011
The Streptococcus pyogenes proteome: Maps, virulence factors and vaccine candidates
No full textStreptococcus pyogenes is an important cause of human morbidity and mortality worldwide. A wealth of genomic information related to this pathogen has facilitated exploration of the proteome, particularly in response to environmental conditions thought to mimic various aspects of pathogenesis. Proteomic approaches are also used to identify immunoreactive proteins for vaccine development and to identify proteins that may induce autoimmunity. These studies have revealed new mechanisms involved in regulating the S. pyogenes proteome, which has opened up new avenues in the study of S. pyogenes pathogenesis. This article describes the methods used, and progress being made towards characterizing the S. pyogenes proteome, including studies seeking to identify potential vaccine candidates. © 2010 Future Medicine Ltd
Prevention and treatment of bronchopneumonia in mice caused by mouse-adapted variant of avian H5N2 influenza A virus using monoclonal antibody against conserved epitope in the HA stem region
No full textThe effects of monoclonal antibody (MAb) C179 recognizing a conformational epitope in the middle of the hemagglutinine (HA) stem region were examined in a mouse model in the experiments of prevention and treatment of lethal bronchopneumonia caused by influenza A virus of H5 subtype. To model the lethal infection, avian nonpathogenic strain A/mallard duck/Pennsylvania/10218/84 (H5N2) was adapted to mice. This resulted in highly pathogenic pneumovirulent mouse-adapted (MA) variant, which was characterized. Three amino acid changes were found in the HA1 subunit of HA of MA virus. One of these was located inside the region of the conformational epitope recognized by MAb C179. However, this substitution was not significant for the recognition of HA and virus neutralization by MAb C179 in vitro and in vivo. Intraperitoneal administration of two different concentrations of MAb C179 one day before or two days after the virus challenge significantly decreased mortality rate. These results suggest that MAb C179 is efficient not only in the prevention and treatment of H1 and H2 influenza virus bronchopneumonia, as was reported previously, but also of H5-induced bronchopneumonia as well, and demonstrate in vivo the existence of a common neutralizing epitope in the HAs of these three subtypes