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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Respiratory Syncytial Virus Pathogenesis and Immune Response in the Cotton Rat Model

Green, Michelle G. 01 September 2017 (has links)
No description available.
82

The effect of temperature on the innate immune response in the lungs against RSV

Chrifi, Wail January 2020 (has links)
A constant flow of various pathogens enters the respiratory system on daily basis through the involuntary mechanism of breathing. Respiratory viral infections are common yet can be fatal in vulnerable populations. Respiratory syncytial virus (RSV) is one of the first and most common viruses that the human population acquire in the first two years of life. Despite the ability of most infants to recover from a RSV infection, many require hospitalization and, in few cases, die from such an infection. The pattern of seasonality of respiratory viruses also applies to RSV. In this work the temperature dependence of infectivity was studied in Hep-2 cells infected with RSV that had been incubated with bronchoalveolar lavage (BAL) fluid. The results indicate a temperature dependence of infectivity. Inhibition of the viral infectivity was observed at three different temperatures 37 ̊C, 40 ̊C and 42 ̊C. The inhibition appears to be linked to the appearance of large agglutinates that appear to reduce the infectivity of RSV. Such a study found that viral neutralization is dependent on a temperature-dependent agglutination reaction. The causality of agglutination formation requires further investigation in order to conclusively confirm the immunological component(s) of this reaction, and how temperature is contributing to this reaction.
83

Identificação do conjunto de proteínas celulares que interagem com a proteína M2-1, e com o complexo M2-1, N e P do vírus Respiratório Sincicial Humano. / Identifying the set of cellular proteins that interact with the protein M2-1, and with the complex M2-1, N and P of Human respiratory syncytial virus.

Araujo, Cinthia de Lima 22 May 2018 (has links)
O Vírus Respiratório Sincicial Humano, do inglês human Respiratory Syncytial Virus (hRSV), é uma das maiores causas de doenças respiratórias agudas, principalmente em crianças e bebês entre seis meses e dois anos de idade. Não há drogas eficazes ou vacina aprovada até o momento para esse vírus, apesar das décadas de intensa pesquisa e grande quantidade de dados sobre ele acumulados. O genoma do hRSV codifica onze proteínas e a compreensão das interações entre essas proteínas virais e as proteínas do hospedeiro é essencial para que possíveis alvos terapêuticos contra o hRSV sejam identificados. No laboratório, anteriormente, foi dado enfoque às interações entre as proteínas celulares e as proteínas virais de matriz (M), nucleoproteína (N) e fosfoproteína (P). Neste trabalho, analisamos as interações da proteína viral M2-1 (cofator essencial para a transcrição) através da mesma estratégia utilizada naqueles experimentos, de fusão a FLAG (gerando FLAG-M2-1) e imunoprecipitação com anticorpos contra esse peptídeo. As proteínas co-imunoprecipitadas, identificadas por espectrometria de massas, foram: poly(A)-binding protein cytoplasmic 1 (PABPC1), Y-box binding protein 3 (YBX3), e Nuclease-sensitive element-binding protein 1 (YBX1). M2-1 é capaz de integrar-se ao complexo chamado de semelhante a corpúsculos de inclusão (IB like, do inglês), formado por N e P, que é similar estruturalmente aos corpúsculos de inclusão encontrados em células infectadas (IBs). Essa propriedade foi usada para analisar que proteínas celulares seriam recrutadas para esse outro nível de organização dessas três proteínas virais, envolvidas na transcrição. O complexo FLAG-N/P/M2-1 co-imunoprecipitou as proteínas celulares: Hsp70, Hsp90 (Heat shock proteins 70 e 90), Npm (Nucleophosmin), que podemos agrupar como chaperonas; PABPC1, YBX1, YBX3, ligantes de RNA; e sub-unidade pICIn do metilossomo, associada a modificação pós-tradução. Detalhamos a análise para YBX3, obtendo evidências adicionais de sua interação com M2-1 em ensaios de complementação de proteína fragmentada (Split-NanoLuc), e de co-localização por imunofluorescência indireta. Finalmente, utilizamos a metodologia de expressão em bactérias para demonstrar a interação entre M2-1 e os domínios funcionais de PABPC1, porém esses ensaios não foram conclusivos. / Human Respiratory Syncytial Virus (hRSV) is one of the leading causes of acute respiratory diseases, especially in children and infants between six months and two years of age. There is no effective drug or vaccine approved so far for this virus, despite decades of intensive research and large amount of data on it. The genome of hRSV encodes 11 proteins and the understanding of the interactions between these viral proteins and host proteins is essential to identify possible therapeutic targets against hRSV. In the lab, previously, was given focus to the interactions between cellular proteins and viral proteins matrix (M), nucleoprotein (N) and phosphoprotein (P). In this paper, we analyze the viral M2-1 (cofactor essential for transcription) protein interactions through the same strategy used in those experiments: fusion with FLAG (generating FLAG-M2-1) and immunoprecipitation with antibodies against this peptide. The co-immunoprecipitated proteins, identified by mass spectrometry, were: Poly (A)-binding protein cytoplasmic 1 (PABPC1), Y-box binding protein 3 (YBX3), and Nuclease-sensitive element-binding protein 1 (YBX1). M2-1 is able to integrate the complex called similar to inclusion bodies (IB like), formed by N and P, which is similar structurally to the inclusion bodies found in infected cells (IBs). This property has been used to analyze which cellular proteins would be recruited for this new level of organization of these three viral proteins involved in transcription. The cellular proteins co-immunoprecipitated with the complex FLAG-N/P/M2-1, were: Hsp70, Hsp90 (Heat shock proteins 70 and 90), Npm (Nucleophosmin), that we can group as chaperones; PABPC1, YBX1, YBX3, RNA ligands; and the methylosome sub-unit pICIn, post-translational modification-associated. We detailed the analysis for YBX3, obtaining additional evidence of its interaction with M2-1 in fragmented protein complementation tests (Split-NanoLuc), and co-localization by indirect immunofluorescence. Finally, we used the methodology of expression in bacteria to demonstrate the interaction between M2-1 and functional domains of PABPC1, but these tests were not conclusive.
84

Avalia??o dos efeitos do tratamento com ?cidos graxos de cadeia curta sobre a infec??o pelo v?rus sincicial respirat?rio

Fernandes, Krist Helen Antunes 03 March 2017 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-07-11T11:29:52Z No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-16T11:22:39Z (GMT) No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) / Made available in DSpace on 2018-07-16T11:30:20Z (GMT). No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) Previous issue date: 2017-03-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
85

Detecção de quasispecies em amostras de vírus respiratório sincicial humano (HSRV) na ausência e na presença de soros policlonais / Quasispecies detection in human respiratory syncytial virus (HRSV) samples in absence and presence of polyclonal serum

Sales, Claudia Trigo Pedroso de Moraes 16 October 2009 (has links)
O vírus respiratório sincicial humano (HRSV) é um dos agentes patogênicos respiratórios de grande importância clínica, tendo em vista que acomete 64 milhões de crianças por ano em todo o mundo. A resposta imune do hospedeiro e a variabilidade genética do HRSV podem interferir na produção de uma vacina eficaz, tal como a presença de quasispecies na população viral. O objetivo deste trabalho foi detectar quasispecies em amostras de HRSV e verificar se soros obtidos da criança na fase convalescente da doença e de sua respectiva mãe selecionam estes mutantes. Uma alteração não sinonímia foi detectada no gene F em um dos clones seqüenciados, enquanto duas alterações sinonímias e duas não sinonímias foram encontradas no gene G do HRSV, sendo as últimas no mesmo nucleotídeo. Um dos clones pré-selecionados com soro humano apresentou a mesma alteração não-sinonímia, encontrada na ausência de anticorpos no gene G. Os resultados sugerem que diferentes sequencias virais presentes em menor quantidade na população podem ser selecionadas pelo sistema imunológico do hospedeiro. / Human respiratory syncytial virus (HRSV) is one of the most important clinical respiratory pathogens, since 64 millions children in the world are infected by this agent every year. Host immunity and viral genetic variability are important factors to a vaccine development, besides quasispecies presence in the viral population. In this work, HRSV quasispecies were detected in clinical samples in absence and presence of human polyclonal serum collected by children in the convalescent phase and mother serum. A non-synonymy variation was found in the F gene in antibodies absence. Four mutations were found at HRSV G2 in polyclonal serum absence. Two were synonymy and two were non-synonymy variation, the last in the same nucleotide. A non-synonymy mutation was found in the G2 region in presence of polyclonal serum collected from child convalescent phase. This alteration was the same of the observed in absence of polyclonal serum so it is possible that host antibodies can selected different viral minority sequences present in the population.
86

Monitoração da ocorrência do Vírus Respiratório Sincicial Bovino (BRSV) em plantéis leiteiros infectados pelo Herpesvírus Bovino Tipo 1 (BoHV-1) /

Affonso, Ingrid Bortolin. January 2010 (has links)
Orientador: Samir Issa Samara / Banca: Sandra Possebon Gatti / Banca: Edvirges Maristela Pituco / Resumo: O Vírus Respiratório Sincicial Bovino (BRSV) é um dos patógenos pertencentes ao complexo respiratório bovino. Apesar de não provocar enfermidade severa na maioria dos casos, há evidências de que este vírus possa facilitar o estabelecimento de outros patógenos. Assim, o presente estudo buscou estabelecer a possibilidade de relação entre o BRSV e o Herpesvírus Bovino Tipo 1 (BoHV-1), em três propriedades leiteiras, localizadas em três municípios do noroeste do Estado de São Paulo. Além disso, visou também monitorar ao longo do tempo os títulos de anticorpos contra o BRSV em bezerros desde o nascimento. Com base em dados previamente estabelecidos, essas propriedades foram categorizadas como tendo alta, média e baixa prevalência de BoHV-1, respectivamente, propriedade A, no município de Viradouro, (78,6%); propriedade B, no município de Altinópolis, (40%); e, propriedade C, no município de Jaboticabal, (1,6%). Com relação à prevalência de BRSV, a propriedade B apresentou maior prevalência sorológica (82,4%), possivelmente por possuir fatores de risco facilitadores para o desenvolvimento da infecção, enquanto que as propriedades A e C mostraram prevalências estatisticamente equivalentes (45,6% e 59,1%, respectivamente), sem qualquer correlação entre as prevalências de BRSV e BoHV-1. A curva dos títulos de anticorpos contra o BRSV em bezerros nas propriedades A e B monitorados ao longo de um ano foi semelhante, pois ambas apresentaram redução dos títulos a partir do sexto até o oitavo mês de idade dos animais, com seguida retomada de títulos cada vez mais elevados, fato característico de infecção natural. A propriedade C apresentou uma dinâmica semelhante, porém, a maior parte dos bezerros manteve-se positiva durante todo o período, com títulos que decresceram e voltaram a aumentar. / Abstract: The Bovine Respiratory Syncytial Vírus (BRSV) is one of the Bovine Respiratory Complex pathogens. The disease caused by this virus is often mild, but there are evidences that this pathogen may ease the establishment of other pathogens. Data on the epidemiology of BRSV are still scarce. Based on that, this study aimed to determine the prevalence and evaluate antibody titers in calves from three farms. Moreover, the relationship between BRSV and the Bovine Herpesvirus Type 1 (BHV-1) was investigated, based on epidemiological data previously determined in these farms. The three farms were categorized as A, in Viradouro municipality, with high prevalence of BHV-1 (78.6%); B, in Altinópolis municipaltity, with intermediate prevalence for this agent (40%); and C, in Jaboticabal municipality, with low prevalence of BHV-1 (1.6%). Farm B showed higher BRSV prevalence (82.4%), maybe due to larger herd and colder climate than farms A and C, which showed equivalent prevalences for BRSV (45.6% and 59.1%, respectively). The curve of antibody titers against BRSV in calves from farms A and B over one year were similar, as both showed lower titers by 6 to 8 months of age, rising up again due to antigenic induction. Farm C showed equivalent dynamics, but calves remained positive all over the year. In disagree to literature data, this experiment did not showed correlation between BRSV and BHV-1 prevalences, maybe due to lack of circulation of the latter. / Mestre
87

Variedade genética de vírus respiratório sincial humano em amostras do grupo B com inserção de 60 nucleotideos, colhidas em crianças atendidas no hospital universitário na cidade de São Paulo. / Genetic variability human respiratory syncytial virus in group B 60-nucleotide-duplication samples from children admitted in university hospital in São Paulo city.

Carvalho, Ariane do Carmo Lins 07 April 2008 (has links)
O vírus respiratório sincicial humano (HRSV) é o principal agente viral causador de doença respiratória em bebês e crianças em idade pré-escolar. A fim de estudar a variabilidade genética de HRSV, grupo B, com inserção de 60 nucleotídeos no gene G, selecionamos amostras de aspirado de nasofaringe de crianças menores de 5 anos de idade, com doença respiratória aguda, admitidas no hospital universitário da Universidade de São Paulo. Testamos 521 amostras, das quais 35,3% foram positivas para HRSV. A região G2 da glicoproteína G foi utilizada para genotipar essas amostras. Todas as amostras do grupo B apresentaram a inserção de 60 nucleotídeos no gene da proteína G, como descrito anteriormente em Buenos Aires, em 1999. As modificações de aminoácidos e nucleotídeos dessas amostras foram comparadas com outras amostras com inserção de 2001-2005. A seqüência de nucleotídeos duplicados foi a cópia exata dos 60 nucleotídeos precedentes em vírus mais antigos, mas as cópias do segmento duplicado acumularam substituições de nucleotídeos em vírus mais recentes. / Human respiratory syncytial virus (HRSV) is the leading viral cause of respiratory illness in infants and young children. In order to study the genetic variability of HRSV group B, with 60-nucleotide duplication in the gene G, we selected nasopharyngeal aspirates samples of children less than five years of age, with acute respiratory illness admitted in the university hospital of São Paulo (USP). We tested 521 samples and the HRSV-detection test positivity rate was 35.3%. The G2 region of glycoprotein G was used as genotyping default. All type B HRSV had a 60-nucleotide duplication in the attachment protein gene like previously described in Buenos Aires, in 1999. Changes in aminoacids and nucleotides in these samples were compaired with other samples with duplication from 2001-2005. The duplicated nucleotide sequence was an exact copy of the preceding 60 nucleotides in early viruses, but copies of the duplicated segment accumulated nucleotide substituions in more recent viruses.
88

Efeitos do exercicio físico sobre a expressão de receptores de glutamato no encéfalo de ratos. / Effects of physical exercise on the glutamate receptors expression on the rat brain.

Real, Caroline Cristiano 17 March 2009 (has links)
Este estudo visou observar os efeitos plásticos induzidos pelo exercício a curto prazo em regiões motoras do encéfalo de ratos. Observou-se a expressão das subunidades GluR1 e GluR2/3. Os animais foram divididos em grupos de: 3 dias(COR3), 7 dias(COR7) e 15 dias(COR15); e um grupo controle(CONT). Empregaram-se as técnicas de imuno-histoquímica e immunoblotting. A expressão de GluR1 no cerebelo, demonstrou um decréscimo em COR3. No hipocampo houve uma queda na expressão em COR3(40%), retornando aos níveis basais em COR7. No córtex cerebral observou-se uma queda da expressão com máxima queda em COR7(52%), retornando à expressão basal em COR15. O estriado não sofreu alterações na expressão de GluR1 ao longo dos primeiros 7 dias, tendo um aumento em COR15(90%). A expressão de GluR2/3 não foi alterada, exceto no cerebelo, onde houve um decréscimo em dois momentos distintos, COR3(55%) e COR15(25%), retornando à expressão basal em COR7. Os nossos dados revelam que o exercício físico a curto prazo foi capaz de promover alterações plásticas ao longo do treinamento. / This study aimed at analyzing the plastic effects of the short-term exercise upon the rat motor area. We check the expression of GluR1 and GluR2/3. We divided into 3 experimental groups based on duration of exercise: 3 days(COR3), 7 days(COR7), and 15 days(COR15); and a control group(CONT). The experimental animals were subjected to a treadmill exercise protocol. The brains were subjected to the techniques of immunohistochemistry and immunoblotting. In the cerebellum, there was a decrease for COR3(17%). In the hippocampus, there was a decrease of the GluR1 expression for COR3 (40%). In the cerebral cortex there was a drop of GluR1 expression for COR3 and COR7(52%). In the striatum, there was no change of GluR1 expression during the first seven days, with a increase for COR15(90%). The GluR2/3 expression did not change in any brain structure analyzed, except in the cerebellum, where there was a significant decrease for two distinct groups, COR3(55%) and COR15(25%). Our data show that short-term physical exercise was able to promote plastic changes during training.
89

Antiviral agents from traditional Chinese medicines against respiratory virus infections. / CUHK electronic theses & dissertations collection

January 2002 (has links)
Ma Shuang-Cheng. / "March 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 289-324). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
90

Antiviral activity of the medicinal plants, Adina pilulifera, Narcissus tazetta and Wikstroemia indica, against respiratory syncytial virus.

January 2008 (has links)
Ho, Wing Shan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 116-137). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Abstract (Chinese Version) --- p.v / Table of Contents --- p.vii / List of Figures --- p.x / List of Tables --- p.xi / List of Abbreviations --- p.xii / Chapter Chapter One: --- General Introduction / Chapter 1.1 --- Respiratory Syncytial Virus (RSV) --- p.1 / Chapter 1.2 --- RSV biology --- p.2 / Chapter 1.3 --- RSV strains --- p.10 / Chapter 1.4 --- RSV pathogenesis and host antiviral responses --- p.11 / Chapter 1.5 --- Prevention of RSV infection --- p.13 / Chapter 1.5.1 --- Vaccines --- p.13 / Chapter 1.5.2 --- Passive anti-RSV antibodies --- p.17 / Chapter 1.6 --- Treatment for RSV infections --- p.20 / Chapter 1.6.1 --- Ribavirin (Virasole®) --- p.20 / Chapter 1.6.2 --- Other antiviral strategies --- p.21 / Chapter 1.6.2.1 --- Attachment inhibitors --- p.22 / Chapter 1.6.2.2 --- Fusion inhibitors --- p.23 / Chapter 1.6.2.3 --- Replication inhibitors --- p.25 / Chapter 1.6.2.4 --- Ethnobotanic medicines --- p.28 / Chapter 1.6.2.4.1 --- Anti-RSV medicinal plant components --- p.31 / Chapter 1.6.2.4.1.1 --- Phenolics and polyphenols --- p.31 / Chapter 1.6.2.4.1.2 --- Flavonoids --- p.32 / Chapter 1.6.2.4.1.3 --- Terpenoids and essential oils --- p.34 / Chapter 1.6.2.4.1.4 --- Lectins --- p.34 / Chapter 1.6.2.4.1.4.1 --- General introduction to lectins --- p.34 / Chapter 1.6.2.4.1.4.2 --- Historical aspects of lectins --- p.35 / Chapter 1.6.2.4.1.4.3 --- Applications of lectins --- p.36 / Chapter 1.7 --- Objectives of the project --- p.37 / Chapter Chapter Two: --- Screening of medicinal plants and phytochemicals for antiviral activity against RSV / Chapter 2.1 --- Introduction --- p.39 / Chapter 2.2 --- Materials and methods --- p.47 / Chapter 2.2.1 --- Medicinal plants and phytochemicals --- p.47 / Chapter 2.2.2 --- Plant extracts preparation --- p.48 / Chapter 2.2.2.1 --- Aqueous extracts --- p.48 / Chapter 2.2.2.2 --- Ethanol extracts --- p.48 / Chapter 2.2.3 --- Cell and virus --- p.49 / Chapter 2.2.4 --- Endpoint titration of RSV infectivity --- p.50 / Chapter 2.2.5 --- Cytotoxicity test --- p.50 / Chapter 2.2.6 --- Antiviral assay --- p.52 / Chapter 2.3 --- Results --- p.53 / Chapter 2.4 --- Discussion --- p.58 / Chapter Chapter Three: --- "Mechanistic studies of anti-RSV actions of various fractions of Adina pilulifera, and daphnoretin, a purified compound from Wikstroemia indica" / Chapter 3.1 --- Introduction --- p.60 / Chapter 3.2 --- Materials and methods --- p.65 / Chapter 3.2.1 --- Fractionation of A. pilulifera ethanol extract --- p.65 / Chapter 3.2.2 --- Cell and virus --- p.65 / Chapter 3.2.3 --- Cytotoxicity test --- p.65 / Chapter 3.2.4 --- Endpoint titration of RSV by TCID50 method --- p.66 / Chapter 3.2.5 --- Antiviral study by CPE reduction assay --- p.66 / Chapter 3.2.6 --- Endpoint titration of RSV by plaque assay --- p.66 / Chapter 3.2.7 --- Antiviral study by plaque reduction assay --- p.67 / Chapter 3.2.8 --- Mode of antiviral action study --- p.68 / Chapter 3.3 --- Results --- p.70 / Chapter 3.4 --- Discussion --- p.76 / Chapter Chapter Four: --- Antiviral activity of Narcissus tazetta proteins / Chapter 4.1 --- Introduction --- p.81 / Chapter 4.2 --- Materials and methods --- p.88 / Chapter 4.2.1 --- Crude proteins extraction from Narcissus tazetta cultivar --- p.88 / Chapter 4.2.2 --- Separation of proteins with affinity column --- p.88 / Chapter 4.2.3 --- Gel filtration of protein fractions on Superose column --- p.89 / Chapter 4.2.4 --- Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.89 / Chapter 4.2.5 --- Electroblotting and N-terminal amino acid sequence analysis --- p.90 / Chapter 4.2.6 --- Protein concentration determination --- p.90 / Chapter 4.2.7 --- Isolation and purification of N. tazetta lectin (NTL) --- p.91 / Chapter 4.2.8 --- Antiviral activities of N. tazetta proteins and NTL --- p.92 / Chapter 4.2.8.1 --- Cell and virus --- p.92 / Chapter 4.2.8.2 --- Cytotoxicity test --- p.92 / Chapter 4.2.8.3 --- Endpoint titration of RSV by TCID50 method --- p.92 / Chapter 4.2.8.4 --- Antiviral study by CPE reduction assay --- p.92 / Chapter 4.2.8.5 --- Endpoint titration of RSV by plaque assay --- p.92 / Chapter 4.2.8.6 --- Antiviral study by plaque reduction assay --- p.93 / Chapter 4.2.8.7 --- Mode of antiviral action study --- p.93 / Chapter 4.3 --- Results --- p.94 / Chapter 4.4 --- Discussion --- p.107 / Chapter Chapter Five: --- General Discussion and Conclusions --- p.111 / References --- p.116

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