RESUMO
The second Venus flyby of the BepiColombo mission offer a unique opportunity to make a complete tour of one of the few gas-dynamics dominated interaction regions between the supersonic solar wind and a Solar System object. The spacecraft pass through the full Venusian magnetosheath following the plasma streamlines, and cross the subsolar stagnation region during very stable solar wind conditions as observed upstream by the neighboring Solar Orbiter mission. These rare multipoint synergistic observations and stable conditions experimentally confirm what was previously predicted for the barely-explored stagnation region close to solar minimum. Here, we show that this region has a large extend, up to an altitude of 1900 km, and the estimated low energy transfer near the subsolar point confirm that the atmosphere of Venus, despite being non-magnetized and less conductive due to lower ultraviolet flux at solar minimum, is capable of withstanding the solar wind under low dynamic pressure.
RESUMO
BACKGROUND: A vancomycin-intermediate Staphylococcus aureus (VISA) (vancomycin minimum inhibitory concentration: 4mg/L) outbreak occurred in an advanced emergency medical service centre [hereafter referred to as the intensive care unit (ICU)] between 2013 and 2014. AIM: Our objective was to evaluate the infection control measures that were successful. METHODS: Seventeen VISA strains were isolated from the sputum of 15 inpatients and the skin of two inpatients. Fourteen VISA strains were recognized as colonization. However, three VISA strains were isolated from the sputum of three inpatients with pneumonia. Environmental cultures were performed and VISA strains were detected in five of 65 sites. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) was performed on 21 VISA strains. FINDINGS: Molecular typing including PFGE and MLST showed that the patterns of 19 VISA strains were identical and those of the other two VISA strains were possibly related. This meant that a horizontal transmission of VISA strains had occurred in the ICU. In August 2013, the infection control team began interventions. However, new inpatients with VISA strains continued to appear. Therefore, in October 2013, the ICU was partially closed in order to try to prevent further horizontal transmission, and existing inpatients with the VISA strain were isolated. Although new cases quickly dissipated after the partial closure, it took approximately five months to eradicate the VISA outbreak. CONCLUSION: Our data suggest that despite the employment of various other infection control measures, partial closure of the ICU was essential in terminating this VISA outbreak.
Assuntos
Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Controle de Infecções/métodos , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Resistência a Vancomicina , Adulto , Idoso , Idoso de 80 Anos ou mais , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Transmissão de Doença Infecciosa/prevenção & controle , Eletroforese em Gel de Campo Pulsado , Serviços Médicos de Emergência , Microbiologia Ambiental , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Pele/microbiologia , Escarro/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificaçãoRESUMO
Because synthetic short peptides bearing critical binding residues, can chemically mimic the folded antigenic determinants on proteins, short synthetic peptides can generate antibodies that react with cognate sequences in intact folded proteins. According to this mimotope theory, we produced site-specific antibodies by immunization with short peptides which overlapped each other and covered the entire protein, and used them for domain mapping of influenza virus RNA polymerase (antibody-scanning method). We also used a tagged-epitope and its monoclonal antibodies for topology mapping of clathrin light chains in clathrin triskelions by electron microscopy. Both methods using specific epitopes in combination with their antibodies enable us to determine the domains of interesting proteins systematically without the need to generate monoclonal antibodies or mutant proteins.
Assuntos
Anticorpos/imunologia , Epitopos/imunologia , Fragmentos de Peptídeos/imunologia , Mapeamento de Peptídeos/métodos , Sequência de Aminoácidos , Reações Antígeno-Anticorpo , Clatrina/química , Clatrina/imunologia , Clatrina/ultraestrutura , Epitopos/química , Imunização , Vírus da Influenza A/enzimologia , Microscopia Eletrônica , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Dobramento de Proteína , Estrutura Terciária de Proteína , RNA Polimerase Dependente de RNA/química , Proteínas Virais/químicaRESUMO
Human papillomavirus (HPV) types 16 and 6b E7 proteins and their chimeric or mutant proteins were analyzed for oligonucleotide-binding activity by surface plasmon resonance-based biomolecular interaction analysis. The results indicated that type 16 E7 protein has stronger nucleic acid-binding activity than that of type 6b E7 protein. In addition, the results also indicated that the zinc finger-like motif in the C-terminal region of the type 16 E7 protein plays an important role in this activity.
Assuntos
Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/metabolismo , Dedos de Zinco , Sítios de Ligação , Humanos , Proteínas Oncogênicas Virais/química , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismoRESUMO
An experimental rat model for vertical transmission of human T cell leukemia virus type I (HTLV-I) was used to examine whether the infection of offspring derived from HTLV-I carrier rats could be established during the suckling period. MT-2 (2 x 10(7)) cells were injected into 5-week-old rats twice, at 2-week intervals. HTLV-I infected or non-infected female rats were mated with HTLV-I carrier male rats. The titer of serum antibodies against HTLV-I in the offspring derived from non-infected dams was less than 1:16 by the agglutination test during the suckling period. The serum antibodies of the offspring derived from the infected dams was less than 1:32 at 1 day after birth and increased steadily to 1:2048 at 14 days. However, the HTLV-I proviral sequences were not detected in any organs of the offspring during the suckling period as determined by the nested double polymerase chain reaction (PCR). These findings indicate that maternal antibodies against HTLV-I were not readily transmitted through the placenta and that the anti-HTLV-I antibodies in the offspring came from the milk of the dams. Furthermore, the HTLV-I infection in the offspring that was derived from the carrier dam may not be established during the suckling period but after weaning.
Assuntos
Portador Sadio , Infecções por HTLV-I/transmissão , Animais , Animais Lactentes , Sequência de Bases , Feminino , Infecções por HTLV-I/imunologia , Masculino , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos F344Assuntos
Doenças do Colo/etiologia , Enterocolite/complicações , Resistência a Meticilina , Infecções Estafilocócicas/complicações , Staphylococcus aureus/efeitos dos fármacos , Doenças do Colo/diagnóstico por imagem , Doenças do Colo/microbiologia , Constrição Patológica/etiologia , Enterocolite/microbiologia , Humanos , Recém-Nascido , Masculino , Radiografia , Infecções Estafilocócicas/microbiologiaRESUMO
Influenza virus RNA polymerase with the subunit structure PB1-PB2-PA is involved in both transcription and replication of the RNA genome, including the unique cap-I-dependent RNase activity. To map the important domains for RNA polymerization, cap-I-dependent RNase, and cap-I-binding activity, we generated site-specific antibodies against overlapping 150-amino-acid peptides that cover each entire subunit. Monospecific antibodies against each subunit inhibited RNA synthesis in vitro. Those against PB1 and PB2 inhibited the cap-I-dependent RNase activity, but those against PB2 alone slightly inhibited the cap-I-binding activity. Antibodies against the N-terminal amino acids 1-159 of PB2 that overlap the PB1-binding site on PB2 and the C-terminal amino acids 501-617 of PA that overlap the putative nucleotide-binding site and PB1-binding site on PA inhibited RNA polymerizing activity as well as monospecific antibodies. Those against the N-terminal (amino acids 1-159); the central region (amino acids 305-559) of PB2, where a part of the cap-binding domain predicted previously is localized; the N-terminal (amino acids 1-222) of PB1; and amino acids 301-517 and 601-716 of PA inhibited the cap-I-dependent RNase activity. The cap-binding domain on PB2 could be mapped in amino acids 402-559, where one of the cap-binding domains mapped previously overlapped.
Assuntos
Anticorpos Antivirais , Imunoglobulina G , Vírus da Influenza A/enzimologia , RNA Polimerase Dependente de RNA/química , Animais , Sequência de Bases , Sítios de Ligação de Anticorpos , Embrião de Galinha , Ensaio de Imunoadsorção Enzimática , Genoma Viral , Vírus da Influenza A/genética , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , RNA Polimerase Dependente de RNA/metabolismo , Deleção de SequênciaRESUMO
Monoclonal antibodies against the PB2 of A/Puerto Rico/8/34 (A/PR/ 8/34) (H1N1) were prepared in order to define the functional domains of the RNA polymerase of influenza virus. The fifteen monoclonal antibodies that were generated were divided into 4 groups on the basis of ELISA binding to PB2 or its peptide fragments. Six Group I antibodies that bound to the PB2 N-terminal region (amino acids 1-104) did not inhibit transcription by the viral ribonucleoprotein complex. A single Group II antibody recognizing the region of amino acids 206-259 inhibited ApG-primed transcription. Groups III and IV antibodies bound to the C-terminal region of amino acids 660-759. Of these, Group III antibodies inhibited transcription. The present results identify multiple monoclonal antibody binding domains in PB2, two of which, when bound by antibodies, negatively affect viral RNA transcription.
Assuntos
Vírus da Influenza A/enzimologia , Proteínas Virais/química , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Ligação Competitiva , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/genética , Mapeamento de Epitopos/métodos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , RNA Polimerase Dependente de RNA , Transcrição Gênica , Proteínas Virais/genética , Proteínas Virais/imunologiaRESUMO
Organisms routinely cultured from throat swabs and infectious agents of sepsis and/or meningitis were reviewed. During the last 12 years, Klebsiella pneumoniae and Escherichia coli have been replaced by Staphylococcus aureus and Pseudomonas aeruginosa as the predominant isolates from throat swabs after admission. These change in the etiologic pattern of infectious agents of sepsis and/or meningitis, i.e., K. pneumoniae, E. coli, S. aureus, P. aeruginosa and staphylococcus epidermidis, were in agreement with the organisms isolated from the throat swabs after admission. The S. aureus isolated from throat swabs after admission showed a decrease in the bacterial activity of cloxacillin, cephazolin and cefotaxime since 1978.
Assuntos
Infecções Bacterianas/epidemiologia , Infecção Hospitalar/epidemiologia , Unidades de Terapia Intensiva Neonatal , Meningites Bacterianas/epidemiologia , Sepse/epidemiologia , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Técnicas Bacteriológicas , Infecção Hospitalar/microbiologia , Feminino , Humanos , Recém-Nascido , Masculino , Meningites Bacterianas/microbiologia , Testes de Sensibilidade Microbiana , Faringe/microbiologia , Sepse/microbiologiaRESUMO
To obtain reagents to functionally map the PA protein, we produced monoclonal antibodies specific to this protein. Twenty-two monoclonal antibodies reacting with PA protein in ELISA were divided into 10 groups on the basis of competitive binding patterns to this protein. Of these, seventeen monoclonal antibodies bound to PA polypeptide spanning amino acids 101-400 and three bound to that of amino acids 518-600, while the other two did not react with any PA polypeptides tested with the exception of full-length PA. Among these monoclonal antibodies, only five reacted with PA in A/PR/8/34 virus-infected cells in indirect immunofluorescence assay. Thus, we obtained monoclonal antibodies that recognize at least 10 distinct regions of the PA molecule. These monoclonal antibodies should be useful in dissecting functions of the PA protein.
Assuntos
Anticorpos Monoclonais , Mapeamento de Epitopos/métodos , Vírus da Influenza A/enzimologia , Vírus da Influenza A/imunologia , RNA Polimerase Dependente de RNA/imunologia , Animais , Ligação Competitiva , Linhagem Celular , Embrião de Galinha , Ensaio de Imunoadsorção Enzimática , Humanos , Vírus da Influenza A/genética , Camundongos , RNA Polimerase Dependente de RNA/genéticaRESUMO
The nucleotide sequences of the genome RNA encoding the RNA polymerase and the 3' non-coding region (NCR) of bovine enterovirus (BEV) serotype I Japanese isolate, MZ468, were determined. The genetic distance between the two BEV serotype I strains, MZ468 and VG-5-27, was calculated by pairwise comparison of nucleotide sequences. The synonymous substitution rate was high (1.40 x 10(-2)/site/year), and of the same order as those of influenza virus HA, HIV-1 gag and env, and enterovirus 70 VP1 genes.
Assuntos
RNA Polimerases Dirigidas por DNA/genética , Enterovirus/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , DNA Viral , Enterovirus/classificação , Enterovirus/genética , Enterovirus/isolamento & purificação , Europa (Continente) , Japão , Dados de Sequência Molecular , Especificidade da EspécieRESUMO
An epidemic of aseptic meningitis caused by human echovirus 9 (E-9) occurred in the summer of 1997 in northern Kyushu, Japan. Sequences of genome position 2504-3358, which encoded a part of VP1, of the nine isolated viruses were determined. An RGD motif and B-C loop were found in all. They were almost identical and closely related to the virulent strain Barty.