RESUMO
AIM: Study of molecular-biological and antigenic features of H5N1 subtype virus strains isolated in southern Siberia in 2005-2009. MATERIALS AND METHODS: Study was performed by using standard procedures according to WHO recommendations. RESULTS: Hemagglutinin gene of H5N1 subtype virus strain isolated in Siberia belongs to 2 genetical lineages: 2.2 and 2.3.2. Strains of these 2 lineages have antigenic differences. All of the strains are highly pathogenic for chicken and white mice. CONCLUSION: H5N1 subtype highly pathogenic influenza virus variants of 2 different antigenic lineages that have antigenic differences circulated in Siberia in 2005-2009. A possible role of antigenic drift in evolution of H5N1 subtype influenza virus is discussed.
Assuntos
Antígenos Virais/genética , Hemaglutininas Virais/genética , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Animais , Aves/virologia , Galinhas/virologia , Humanos , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Sibéria/epidemiologiaRESUMO
AIM: To analyze influenza viruses isolated in the 2008-2009 autumn-winter season, and to test sera collected in the south of Western Siberia during the beginning and the end of the epidemic seasons from 2007 until the A/H1N1 pandemic. MATERIALS AND METHODS: Total 149 clinical samples were analyzed and 2190 blood sera were tested. During the 2008-2009 season 17 influenza viruses were isolated. 9 of these were A/H1N1, 5-were A/H3N2, and 3 were influenza B viruses. The nucleotide sequences and amino acid composition of influenza A virus hemagglutinin (HA) were compared with reference strains. RESULTS: Among A/H1N1 viruses circulating in Novosibirsk region three viruses contained four amino acid replacements in antigen sites Ca, Cb and Sb. In A/ H3N2 viruses from Novosibirsk, 2 amino acid substitutions were detected in antigen sites B and E. CONCLUSION: Based on genotyping influenzae epidemic on February to April of 2009 in the south of western Siberia was associated with influenza viruses A/H1N1, A/H3N2, and B. All A/H3N2 influenza virus isolates were variants of reference A/Brisbane/10/2007(H3N2) and A/ H1N1 influenza viruses isolates were similar to reference A/Brisbane/59/2007(H1N1).
Assuntos
Monitoramento Ambiental , Epidemias , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza B/classificação , Influenza Humana/epidemiologia , Substituição de Aminoácidos , Monitoramento Epidemiológico , Genes Virais/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/genética , Vírus da Influenza B/isolamento & purificação , Influenza Humana/sangue , Influenza Humana/imunologia , Epidemiologia Molecular , Estudos Soroepidemiológicos , Sibéria/epidemiologiaRESUMO
AIM: To study circulation of influenza A viruses in western part of Mongolia. MATERIALS AND METHODS: Isolation and characterization of influenza viruses was performed according to recommendations of WHO. RESULTS: Circulation of influenza A viruses subtypes H3N6, H4N6, H1N1, H13N8 in different wild bird species in western part of Mongolia was documented. CONCLUSION: Taxonomic and ecologic heterogeneity of bird species involved in continuous circulation of influenza A viruses was revealed. Subtype H13N8 was isolated for a first time from herring gull on territory of western Mongolia.
Assuntos
Aves/virologia , Reservatórios de Doenças/virologia , Monitoramento Ambiental , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Animais , Aves/classificação , Monitoramento Epidemiológico , Vírus da Influenza A/classificação , Influenza Aviária/virologia , Mongólia/epidemiologiaRESUMO
The effects of antagonist of alpha2-adrenoceptors yohimbine and their agonist clonidine on Bax and Bcl-XL mRNA levels in neonatal rat brain were studied. Yohimbine decreased Bax mRNA level in the cerebellum, increased the ratio between Bcl-XL and Bax mRNA levels in the cerebellum, cortex, and hippocampus, and increased Bcl-XL mRNA level in the cortex and hippocampus of 6-day-old-rat pups 24 h after injection. Administration of clonidine 20 min after yohimbine administration abolished its effect on Bcl-XL mRNA level in the hippocampus. The data obtained indicate that the blockade of alpha2-adrenoceptors induces antiapoptotic changes in the developing rat brain, some of which can be abolished after coadministration with the agonist of these receptors.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 2 , Antagonistas de Receptores Adrenérgicos alfa 2 , Apoptose , Encéfalo/efeitos dos fármacos , Proteína bcl-X/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Clonidina/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Ligantes , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Ioimbina/farmacologia , Proteína bcl-X/genéticaRESUMO
Antisense oligonucleotide to alpha2A-adrenoceptors increased the levels of mRNA (reverse polymerase chain reaction) and protein for a key executioner protease of apoptosis caspase-3 (immunoblotting assay) in the cerebral cortex of newborn rats. The relationship between the observed effect and low expression of alpha2-adrenoceptors was confirmed by the possibility of correcting this phenomenon by clonidine (stimulator of alpha2-adrenoceptors).
Assuntos
Antagonistas de Receptores Adrenérgicos alfa 2 , Inibidores de Caspase , Córtex Cerebral/metabolismo , Animais , Animais Recém-Nascidos , Apoptose , Sequência de Bases , Caspase 3/genética , Caspase 3/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/crescimento & desenvolvimento , Oligodesoxirribonucleotídeos Antissenso/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos alfa 2/genética , Receptores Adrenérgicos alfa 2/metabolismoRESUMO
Bax mRNA level in fetal rat brain stem increases by day 40 of life and then decreases, while level of Bcl-XL mRNA reaches the adult value over one month. Bax mRNA level in the cerebral cortex decreases from day 8 to day 90 of life, while Bcl-XL mRNA level does not change. Judging from Bcl-XL/Bax mRNA ratio, cortical cells exhibit higher readiness to apoptosis than brain stem cells.
