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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.
141

Development of a novel cell-based screening platform to identify inhibitors of viral interferon antagonists from clinically important viruses

Vasou, Andri January 2016 (has links)
All viruses encode for at least one viral interferon (IFN) antagonist, which is used to subvert the cellular IFN response, a powerful antiviral innate immune response. Numerous in vitro and in vivo studies have demonstrated that IFN antagonism is crucial for virus survival, suggesting that viral IFN antagonists could represent promising therapeutic targets. This study focuses on Respiratory Syncytial Virus (RSV), an important human pathogen for which there is no vaccine or virus-specific antiviral drug. RSV encodes two IFN antagonists NS1 and NS2, which play a critical role in RSV replication and pathogenicity. We developed a high-throughput screening (HTS) assay to target NS2 via our A549.pr(ISRE)GFP-RSV/NS2 cell-line, which contains a GFP gene under the control of an IFN-stimulated response element (ISRE) to monitor IFN- signalling pathway. NS2 inhibits the IFN-signalling pathway and hence GFP expression in the A549.pr(ISRE)GFP-RSV/NS2 cell-line by mediating STAT2 degradation. Using a HTS approach, we screened 16,000 compounds to identify small molecules that inhibit NS2 function and therefore relinquish the NS2 imposed block to IFN-signalling, leading to restoration of GFP expression. A total of twenty-eight hits were identified; elimination of false positives left eight hits, four of which (AV-14, -16, -18, -19) are the most promising. These four hit compounds have EC₅₀ values in the single μM range and three of them (AV-14, -16, -18) represent a chemically related series with an indole structure. We demonstrated that the hit compounds specifically inhibit the STAT2 degradation function of NS2, not the function of NS1 or unrelated viral IFN antagonists. At the current time, compounds do not restrict RSV replication in vitro, hence hit optimization is required to improve their potency. Nonetheless, these compounds could be used as chemical tools to determine the unknown mechanism by which NS2 mediates STAT2 degradation and tackle fundamental questions about RSV biology.
142

Études épidémiologiques régionales et nationales des infections virales respiratoires sévères de l’enfant : intérêts pour la prise en charge préventive et curative / Regional and national epidemiological studies on respiratory viral infections in children : preventive and curative interests

Fléchelles, Olivier 30 November 2018 (has links)
Les virus respiratoires induisent de nombreuses et fréquentes pathologies en pédiatrie avec une morbidité importante. Ces virus sont bien connus car étudiés depuis longtemps mais ils sont en évolution constante. L’apparition des antibiotiques, des antiviraux, des soins intensifs, de la vaccination, les connaissances sur l’hygiène ont transformé l’impact de ces virus sur les populations humaines. Nos modes de vie principalement citadins favorisent la diffusion virale locale par le regroupement de presque tous les enfants dans des crèches ou des écoles. De même l’explosion récente des moyens de transport en particulier aérien qui ont reliés physiquement tous les pays du monde entre eux et qui accentuent la diffusion virale mondiale. Faut-il appliquer les mêmes raisonnements dans tous les pays du monde pour lutter contre ces infections ? Cette thèse apporte de nouvelles connaissances sur ce sujet en se focalisant sur les virus influenza et le virus respiratoire syncytial :1) Pendant la pandémie H1N1 au Canada, la mise en évidence de l’augmentation des hospitalisations des enfants asthmatiques, paradoxalement moins souvent ventilés durant leurs séjours en réanimation pédiatrique.2) L’intérêt de la vaccination contre le virus pandémique H1N1 pour diminuer le recours à la ventilation assistée chez les enfants hospitalisés en réanimation pédiatrique.3) Le Canada n’a pas connu de 3ème vague pandémique en raison d’une campagne vaccinale massive qui bien que tardive, a été efficace même 1 an plus tard.(4) La saisonnalité de la bronchiolite dans les régions tropicales est très différente de celle retrouvée dans les pays tempérés et nécessite de réajuster les recommandations de prise en charge à l’aune des données localesEn décrivant la cinétique et l’impact de la pandémie grippale de 2009 sur les enfants hospitalisés en soins intensifs pédiatriques au Canada d’Octobre 2009 à Mars 2011, en comparant cette cohorte à une cohorte similaire en France Hexagonale, et en décrivant 2 épidémies de VRS en Martinique en 2007 et 2008 pour confronter ces données avec celles décrites dans les pays tempérés, ce travail illustre combien nos connaissances doivent toujours être remises en question du fait de l’évolution du climat, de l’évolution de la société et de l’évolution des connaissances médicales / Respiratory viruses are responsible for much pediatric pathology with significant morbidity. These viruses are well known for a long time but are subject to constant changes. The development of antibiotics, antivirals, intensive care, vaccination, knowledge on hygiene has modified the impact of these viruses on human populations. Our predominantly urban lifestyles support local viral spread by bringing almost all children together in nurseries or schools. In the same way, the large use of modern transport facilities especially air transport (which connect all continents between them) facilitate the world viral spread. In this new environment, should we apply the same medical reasoning all over the world to fight against these infections? This thesis brings new knowledge on this topic, focusing on influenza virus and syncytial respiratory virus:1) During Influenza A(H1N1)pdm09, hospitalizations of children with asthma increase, but they were least often to be ventilated during their pediatric intensive care stay.2) The value of vaccination against the pandemic virus to reduce the use of assisted ventilation in children hospitalized in Pediatric Intensive Care Unit.3) Canada did not experience a third pandemic wave in 2010 because of a massive vaccination campaign that, even late, was effective one year later.4) The bronchiolitis season in the tropics is different from what we know in temperate countries. It is mandatory to adjust management recommendations in the light of regional data.By describing the kinetics and impact of the 2009 influenza pandemic on children in pediatric intensive care in Canada from October 2009 to March 2011, comparing this cohort to a similar cohort in France, and comparing 2 epidemics of VRS in Martinique (French West Indies) in 2007 and 2008 with those that have been carried out in temperate countries, this thesis is an example why we have to constantly question our knowledge because of climate change, change in society and medical knowledge evolution.
143

Avaliação das infecções respiratórias virais em pacientes com fibrose cística / Respiratory viral infections evaluation in cystic fibrosis patients

Almeida, Marina Buarque de 03 April 2010 (has links)
O objetivo deste estudo foi avaliar o impacto clínico, funcional e bacteriológico das infecções respiratórias virais nos pacientes com fibrose cística durante um ano. A identificação viral foi feita por métodos de biologia molecular para os seguintes virus: Vírus sincicial respiratório, Influenza A e B, Parainfluenza 1, 2 e 3, Adenovírus, Rinovírus, Metapneumovírus humano, Coronavírus, Enterovírus e Bocavírus. Foram 408 amostras com identificação viral em 199 amostras (48,7%). O Rinovírus foi o mais prevalente sendo identificado em 140 amostras (34,31%), mas contrastando com outros estudos em fibrose cística e em outras doenças pulmonares crônicas, o Rinovírus não mostrou ter impacto clínico, funcional ou bacteriológico significativo nos pacientes com fibrose cística / The objective of this study was to evaluate the clinical, functional and bacteriological impact of the viral respiratory tract infections in cystic fibrosis patients over one year. Viral identification was done through molecular biology methods for the following virus: Respiratory syncytial virus, Influenza A and B, Parainfluenza viruses type 1 to 3, Adenovirus, Rhinovirus, Human metapneumovirus, Coronavirus, Enterovirus and Human bocavirus. 199 (48,7%) samplings among 408 were positive for at least one virus. Rhinovirus was the virus with a higher prevalence, which was identified in 140 samplings (34,31%), but without clinical, functional or bacteriological impact contrasting with other studies in patients with cystic fibrosis and other chronic lung diseases
144

Caracterização molecular de Vírus Respiratório Sincicial Humano (HRSV) isolados na cidade de São Paulo no período de 2007 a 2008. / Characterization and epidemiologic of Human Respiratory Syncytial Virus (HRSV) isolated in São Paulo city in 2007-2008.

Zukurov, Jean Paulo Lopes 23 April 2010 (has links)
O Vírus Respiratório Sincicial Humano (HRSV) é considerado o principal causador de doenças agudas do trato respiratório inferior durante a infância, sendo o principal responsável por um elevado índice de hospitalização de crianças com até cinco anos de idade. Possui distribuição mundial, podendo acometer todas as faixas etárias, entretanto as crianças de 6 semanas a 9 meses são as que desenvolvem problemas mais sérios, como pneumonia e bronquiolite. A epidemia de HRSV apresenta uma sazonalidade bem clara, ocorrendo anualmente no período de outono tardio, inverno ou início da primavera, mas não durante o verão. No presente estudo foi realizada a análise da região G2 da glicoproteína G do HRSV. Um total de 44 amostras positivas para o HRSV do Hospital Universitário (HU) da Universidade de São Paulo (USP), nos anos de 2007-2008, foram seqüenciadas e posteriormente analisadas, sendo então comparadas com seqüências obtidas do NCBI/GeneBank. A análise filogenética mostrou que os genótipos GA2 e GA5, do grupo A, foram os predominantes nos anos de 2007 e 2008, alternando o padrão verificado nos anos anteriores, onde os genótipos do grupo B foram altamente predominantes. A comparação das mutações sinônimas e não sinônimas mostrou uma grande evidência de seleção positiva nos genótipos GA2 e GA5 do grupo A. / Human Respiratory Syncytial Virus (HRSV) is considered the most common cause of lower respiratory tract disease in infants and young children and are the main guilty for the elevated children hospitalizations rate under 5 years of age. The HRSV has a world-wide distribution, being able to attack all the ages however the 6 weeks to 9 months children of are the ones that develop more serious problems as pneumonia and bronquiolite. The HRSV outbreak presents a well defined season, occurring annually in the delayed falls period, winter or springs beginning, but not during the summer. In the present study, we performed a phylogenetic analysis from G2 region of HRSV G glycoprotein. Forty four samples positive for HRSV from University Hospital (UH) of University of Sao Paulo (USP) in 2007-2008, were submitted to sequencing by PCR and compared with GenBank sequences. Phylogenetic analysis revealed that HRSV group A genotypes GA2 and GA5 was the predominant in 2007-2008, alternating the standard verified in the previous years, where the group B genotypes had been highly predominant. Comparison of the synonymous/nonsynonymous mutation ratios showed greater evidence for positive selection pressure for group A genotypes GA2 and GA5.
145

Aplicação de ensaio imunoenzimático para detecção de anticorpos contra o vírus respiratório sincicial em repectores de transplante de células tronco-hematopoéticas / Enzime-linked immunosorbent assay for detection of respiratory syncytial virus antibodies in hematopoietic stem cell transplant recipients

Paz Junior, José de Paula 18 August 2008 (has links)
O vírus respiratório sincicial (RSV) é responsável por importante morbidade em receptores de transplante de células tronco-hematopoéticas (TCTH), especialmente no período que antecede a enxertia. A imunidade induzida pela infecção pelo RSV é transitória e as reinfecções são freqüentes. O comportamento e papel dos anticorpos anti-RSV em receptores de TCTH é desconhecido. Em amostras de soro estocadas, ensaio imunoenzimático (ELISA) foi aplicado para detecção de anticorpos anti-RSV para avaliar a dinâmica desses anticorpos antes e após o TCTH, em pacientes com e sem infecção pelo RSV, bem como a resposta de anticorpos específicos nos pacientes com infecção pelo RSV diagnosticada por imunofluorescência direta. A mediana do tempo de coleta das amostras pré-TCTH foi de -35 e -44 dias nos casos e controles, respectivamente, com média de títulos de anticorpos anti-RSV de 2490 UA/mL e 2872 UA/mL, respectivamente. Após o transplante, as medianas de tempo das 3 amostras analisadas dos pacientes com infecção pelo RSV foram d+14, d+52 e d+89 e os respectivos títulos de anticorpos foram 2457 UA/mL, 2715 UA/mL e 2950 UA/mL. Nos pacientes sem infecção pelo RSV (controles), as medianas de tempo das 3 amostras analisadas foram d+9, d+69 e d+93 e os respectivos títulos de anticorpos foram 2738 UA/mL, 2794 UA/mL e 2642 UA/mL. Não houve diferença estatística entre os dois grupos. Nenhum dos pacientes com infecção pelo RSV apresentou elevação de quatro vezes nos títulos de anticorpos / Respiratory syncytial virus (RSV) infection can cause significant morbidity and mortality in haematopoietic stem cell transplant (HSCT) recipients, especially when upper respiratory tract infection (RTI) progresses to lower RTI, which is expected to occur in more than 50% of the patients. The humoral immunity induced by RSV infection is transient and reinfections are frequent. The dynamics and role of anti-RSV antibodies in HSCT recipients are unknown. In stored serum samples, an enzyme-linked immunosorbent assay (EIA) was applied to evaluate the dynamics of anti-RSV antibodies in HSCT recipients with and without RSV infection, as well as the specific humoral response in HSCT recipients with RSV infection diagnosed by direct immunofluorescent assay in nasal wash samples. Pre-transplant samples were selected at a median time of 35 and 44 days and the mean concentration of RSV antibodies were 2490 AU/mL and 2872 AU/mL, in cases and controls, respectively. After HSCT, serum samples from patients with RSV infection (cases) were evaluated at median time of 14, 52 and 89 days, and the respective mean concentrations of anti- RSV antibodies were 2457 AU/mL, 2715 AU/mL and 2950 AU/mL. In patients without RSV (controls), serum samples were evaluated at median time of 9, 69 and 93 days, and the respective mean concentrations of anti-RSV antibodies were 2738 AU/mL, 2794 AU/mL e 2642 AU/mL. Difference was not statistically significant. No patient developed a four-fold rise in RSV antibody titers
146

Vacina??o com pept?deo M209-223 do v?rus sincicial respirat?rio (VSR) promove uma resposta imune protetora contra infec??o e reduz a inflama??o no pulm?o / Vaccination with respiratory syncytial virus (RSV) M209-223 peptide promotes a protective immune response against infection and reduces lung inflammation

Fazolo, Tiago 20 March 2017 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-02-16T19:08:17Z No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-02-22T17:20:04Z (GMT) No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) / Made available in DSpace on 2018-02-22T17:35:15Z (GMT). No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) Previous issue date: 2017-03-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Respiratory syncytial virus (RSV) is the most common etiologic agent in severe lower respiratory tract infections (LRTI) in children. RSV-associated LRTI is the main cause of bronchiolitis, pneumonia and exacerbation of asthma. This infection is responsible for the high rates of hospitalizations related to respiratory diseases worldwide, especially in children younger than 2 years. Currently, annual mortality rate due to RSV infections is worrying worldwide and is estimated at approximately two hundred thousand cases. The treatment strategies to RSV infections are limited. Ribavirin is an approved drug for use in RSV infections, but its use is limited due to adverse side-effects and risks posed to health professionals who handle it. Palivizumab is a monoclonal antibody which targets RSV F glycoprotein and its use is only indicated as a prophylactic measure. This treatment is already accepted in several countries for groups of high risk children (premature children, with chronic lung disease and with congenital heart disease). However, palivizumab has a high cost for public health and is not available in all countries. The development of an effective RSV vaccine to generate a long-lasting immunological memory response that prevents infection may be the best alternative because it will reduce high public health expenditures with antiviral drugs and monoclonal antibodies. The first attempt in the search for a vaccine against RSV was in the 1960s. This vaccine produced high levels of serum antibodies but could not protect against infection. Children who were vaccinated developed a more serious disease when later infected with the same virus. To date, there is no licensed vaccine for RSV, so the search for effective vaccines is an important focus of research. Natural RSV infections do not induce lasting protective memory, and multiple reinfections can occur lifetime. Nasal secretions from infected infants presented a small number of regulatory CD4 T cells (Treg) in peripheral blood, an increase in interleukin 4 (IL-4) production and T helper type 2 (Th2) response. Treg cells are important for controlling an exacerbated increase in immune responses. A reduction of the Tregs caused by the RSV infection generates an exacerbation of the pulmonary disease due to a Th2 response. The M209-223 RSV peptide was identified to increase IFN-? production by peptide-specific CD4 T cells after challenge with the virus. The treatment with this peptide also induced an increase in pulmonary Treg frequency in infected mice. Recently, it has also been shown that Tregs aid in the development of a T CD8+ effector response, which is crucial for the control of RSV viral load. Our hypothesis is that the RSV M209-223 peptide impacts in the differentiation of CD4 T cells, increasing the population of specific Treg, reducing lung inflammation and modulating the anti-RSV immune response. This peptide in animal model induces the differentiation of specific Treg. Our findings suggest that vaccination with M209-223 peptide results in the differentiation of specific CD4 T cells into conventional effectors and Treg cells. Vaccination with this peptide decreased the expansion of a Th2 response in animals infected with RSV, protecting both the infection site and systemically. We believe that this approach could be an important component in vaccination strategies against this virus. / O v?rus sincicial respirat?rio (VSR) ? o agente etiol?gico mais comum nas infec??es graves do trato respirat?rio inferior (TRI) em crian?as. As infec??es do TRI associada com o VSR s?o a principal causa de bronquiolite, pneumonia e exacerba??o da asma. As TRI causadas pelo VSR s?o respons?veis pelas altas taxas das hospitaliza??es relacionadas ?s doen?as respirat?rias em todo o mundo, principalmente em crian?as menores de dois anos. Atualmente a taxa de mortalidade anual mundial devido ?s infec??es pelo VSR ? preocupante e ? estimada em aproximadamente duzentas mil crian?as. As estrat?gias de tratamento contra o VSR utilizadas s?o limitadas. A ribavirina ? um f?rmaco aprovado no uso para infec??es pelo VSR, por?m sua utiliza??o ? limitada devido aos efeitos secund?rios adversos e aos riscos que representam para os profissionais da sa?de que o manipulam. O palivizumabe ? um anticorpo monoclonal dirigido contra a glicoprote?na F do v?rus e sua utiliza??o ? apenas como medida profil?tica. Este tratamento j? ? aceito em v?rios pa?ses nos grupos de crian?as de alto risco (crian?as prematuras, com doen?a pulmonar cr?nica e com cardiopatia cong?nita). Entretanto o palivizumabe tem um alto custo para sa?de p?blica, n?o sendo disponibilizado em todos os pa?ses. O desenvolvimento de uma vacina eficaz contra o VSR pode ser a melhor alternativa, pois ao gerar resposta de mem?ria duradoura que previne a infec??o e reduz, desta forma, os altos gastos com a sa?de p?blica, com os f?rmacos antivirais e com os anticorpos monoclonais. A primeira tentativa na busca de uma vacina contra o VSR foi na d?cada de 60. A vacina produzida estimulou n?veis moderadamente elevados de anticorpos no soro, mas n?o conseguiu proteger contra ? infec??o. As crian?as que foram vacinadas desenvolveram uma doen?a mais grave quando mais tarde infectados com o v?rus. At? o presente momento n?o existe nenhuma vacina licenciada para o VSR. Desta forma, a busca de vacinas eficazes constitui um importante foco de pesquisa em todo mundo. As infec??es naturais pelo VSR n?o induzem mem?ria protetora duradoura, ocorrendo m?ltiplas reinfec??es ao longo da vida. Em crian?as infectadas, observou-se um n?mero reduzido de c?lulas T CD4+ regulat?rias (Treg) no sangue perif?rico, um aumento na produ??o de interleucina 4 (IL-4) e uma resposta T helper do tipo 2 (Th2) nas secre??es nasais. As c?lulas Treg s?o importantes para controlar um aumento exagerado da resposta imunol?gica. Por este fato acredita-se que quando h? uma redu??o das Tregs causada pela infec??o do VSR ocorre uma exacerba??o da doen?a pulmonar devido uma resposta Th2. Foi identificado que o pept?deo M209-223 do VSR aumenta a produ??o de IFN-? nas c?lulas T CD4+ ap?s o desafio com VSR. O tratamento com este mesmo pept?deo tamb?m apresentou um aumento na frequencia de c?lulas Treg ap?s infec??o prim?ria pelo VSR. Recentemente tamb?m foi demonstrado que as Tregs auxiliam no desenvolvimento de uma resposta efetora T CD8+, que ? crucial para o controle da carga viral do VSR. Nossa hip?tese ? que o pept?deo M209-223 do VSR influencia na diferencia??o das c?lulas T CD4+, aumentando a popula??o de c?lulas T efetoras e regulat?rias espec?ficas, reduzindo a inflama??o pulmonar e modulando a resposta imune. Os nossos resultados sugerem que a vacina??o com pept?deo M209-223 resulta na diferencia??o de c?lulas T CD4+ espec?ficas em efetoras convencionais, que produzem mais IFN-? e em c?lulas Treg. A vacina??o com este pept?deo diminuiu a expans?o de uma resposta Th2 nos animais infectados com o VSR, protegendo da inflama??o exacerbada tanto no local da infec??o como sistemicamente. Acreditamos que esta abordagem pode constituir um componente importante nas estrat?gias de vacina??o contra este v?rus.
147

Caracterização molecular das cepas do Vírus Sincicial Respiratório identificadas nos anos de 2001 e 2002 em unidade de transplante de células tronco hematopoéticas / Molecular characterization of strains of Respiratory Syncytial Virus in Hematopoietic Stem Cell Transplant Unit identified in 2001 and 2002

Machado, Adriana Freire 12 November 2007 (has links)
O Vírus Sincicial Respiratório (RSV) é reconhecido como agente causador de infecção nosocomial entre receptores de pacientes de células-tronco hematopoéticas causando morbidade e mortalidade consideráveis nesses pacientes. O objetivo desse estudo foi caracterizar as cepas do RSV isoladas de receptores de transplante de células-tronco hematopoéticas (TCTH) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo durante sua estação. As cepas do RSV foram tipadas (em grupo A ou B) e genotipadas. Das sete cepas analisadas dos receptores de TCTH durante o ano de 2001, somente duas pertenciam ao grupo B, as outras cinco eram pertencentes ao grupo A. Dessas sete cepas, três eram altamente relacionadas e haviam infectados pacientes que freqüentavam o ambulatório. Em 2002, das doze cepas analisadas, três pertenciam ao grupo A e as outras nove pertenciam ao grupo B. Sete cepas eram altamente relacionadas entre elas e eram também de pacientes de ambulatório sugerindo que a transmissão em hospital-dia era mais provável. Enfim, múltiplços genótipos do RSV co-circularam nas unidades de TCTH (ambulatório e enfermaria) do Hospital das Clínicas entre 2001 e 2002. A transmissão nosocomial foi mais provável ocorrer no ambulatório da unidade de TCTH quando comparada à enfermaria. Políticas de controle de infecção devem ser também implementadas em ambulatórios para evitar transmissão nosocomial do RSV e outros vírus respiratórios em pacientes de ambulatório. / Respiratory Syncytial Virus is recognized as the leading cause of nosocomial respiratory infection among recipients of hematopoietic stem cell transplant (HSCT) causing considerable morbity and mortality among theses patients. The aim this study was characterize the strains of Respiratory Syncytial Virus in recipients Hematopoietic Stem Cell Transplant Unit (HSCT) at Hospital das Clínicas, University of São Paulo Medical School during RSV season in symptomatic HSCT recipients at Hospital das Clínicas. The strains of RSV was typed (in group A or B) and genotyped. Of the seven strains analyzed from HSCT recipients during 2001, only two belonged to group B, the other five belonged to group A. Of these seven strains, three were closely related and were from outpatients. In 2002 , of the twelve strains analyzed, three belonged to group A and the other nine belonged to group B. Seven strains were closely related and were also from outpatients suggesting that nosocomial transmission in hospital-day was more likely. In conclusion, multiples genotypes of RSV co-circulated in the Hematopoietic Stem Cell Transplant units (ward and dayhospital) of Hospital das Clínicas between 2001 and 2002. Nosocomial transmission was more likely to occur at the HSCT Day-hospital as compared to the HSCT ward. Infection control practices should be also implemented at Day-hospital Units to avoid nosocomial transmission of RSV and other respiratory viruses in outpatient units.
148

Variabilidade genética da proteína SH (Small hydrophobic protein) do vírus sincicial respiratório humano isolado de crianças na cidade de São Paulo. / Genetic variability of protein SH of human respiratory syncytial virus (HRSV) of samples collected the children in São Paulo City.

Silva, Hildenêr Nogueira de Lima e 21 August 2009 (has links)
O vírus sincicial respiratório humano (VSRH) é o agente viral mais freqüentemente relacionado a doenças do trato respiratório inferior em crianças abaixo de um ano de idade. Analíse da varibilidade antigênica e gênica mostraram que o VSRH pode ser divido em dois grupos: A e B. O vírus é um membro do gênero Pneumovirus pertencente a família Paramyxoviridea, e possui três principais proteínas que são: glicoproteina F (fusão), glicoproteina G (adesão), glicoproteina SH (pequena proteína hidrofóbica). A proteína F é responsável pela fusão da célula ao vírus, enquanto a proteína G tem papel fundamental na replicação do vírus, porém a função da proteína SH, ainda não está bem definida, estudos recentes mostram-na como responsável por inibir a sinalização do fator de necrose tumoral alfa (TNF-a). Neste estudo foram colhidas amostras de 965 crianças, entre os anos de 2004 e 2005, dentre as quais 424 foram positivas. 117 amostras foram seqüenciadas a proteína SH e G e comparadas com amostras que circularam mundialmente. A analíse filogenética mostrou uma baixa variabilidade entre os genótipos estudados tanto do grupo A quanto do B. / The human respiratory syncytial virus (HRSV) is the major cause of lawer respiratory tract infections in infantis, young children and elderly. Analysis of the antigenic and genetic variability has shown that there are two groups of the virus HRSV, A and B. The virus (HRSV) is a member of the genus pneumovirus in the paramyxoviridae family. The virus encodes three membrane-bound glicoproteins, namely the fusion (F) attachment (G) and small hydrophobic (SH) proteins. The F mediates fusion of the virus and cell membranes and the G proteins is involved in virus attachment. The biological properties of the F and G glicoproteins and role that they play during virus replication relatively well understood, however the functional significance of the SH protein during replication remains unclear, although recent study shown that it can inhibit TNF-alpha. In this study, HRSV strains were isolated from nasopharyngeal aspirates collected from 965 children between 2004 and 2005, yielding 424 positive samples. We sequenced the small hydrophobic protein (SH) gene and protein (G) of 117 samples and compared them with other viruses identified worldwide. The phylogenetic analysis showed a low genetic variably among the isolates but allowed us to classify the viruses into different genotypes for the A and B HRSV strains.
149

Infecções respiratórias por vírus sincicial respiratório em criança de creche.

Lourenção, Luciano Garcia 26 October 2006 (has links)
Made available in DSpace on 2016-01-26T12:51:55Z (GMT). No. of bitstreams: 1 lucianogarcialourencao_dissert.pdf: 833601 bytes, checksum: 00a7823458263c5ee5f67007f775ba5b (MD5) Previous issue date: 2006-10-26 / Respiratory infections account for more than 25% of the whole medical, pediatric, outpatient and hospital services. Around 90% of those infections are related with viral agents. RSV is an important agent identified in those diseases. This study aimed at assessing the frequency of Respiratory Syncytial Virus (RSV) in children aged from 0 to 6 years with upper respiratory infection diseases (URID) from a nursery school, and to associate the clinical and epidemic data of mild degree of URID with the viral agent. The children had a daily follow-up in the period from July 2003 to July 2004, and viral investigation for RSV by means of Polimerase Chain Reaction (PCR), in the children's nasopharyngeal secretions that presented signs of breathing infection. A total of 259 events of URID in 173 children have occurred. A hundred twenty-two (70.5%) children were over 2 years in the beginning of the follow-up and 94 (54.3%) were male. The monthly number of episodes ranged from 0 to 53. RSV was diagnosed in 27 (10.5%) samples, and it was more frequent between the months of July to September. The signs observed in the children with RSV infection were coryza in 26 (96.3%) episodes, nasal obstruction in 19 (70.4%), coughs in 15 (55.6%), wheezing in 3 (11.1%) and sneeze and fever in 2 (7.4%) episodes. Antibiotics were administered in 16 (6.2%) episodes of breathing infection. One (3.7%) infection episode by RSV received treatment with antibiotic. One (0.4%) serious episode had developed for hospitalization. A high frequency of RSV was observed among the children from nursery school with mild breathing infections, mainly from the beginning of the autumn to the spring; the most frequent signs in the infections for RSV were cough, coryza and nasal obstruction; there was association between nasal obstruction and infections by RSV. / As infecções respiratórias são responsáveis por mais de 25% de todo o atendimento médico pediátrico, ambulatorial e hospitalar. Em torno de 90% dessas infecções estão relacionadas com agentes virais. O Vírus Sincicial Respiratório (VSR) é um importante agente identificado nessas afecções. Esse estudo objetivou estimar a freqüência do VSR em crianças com idade entre 0 e 6 anos com infecção das vias aéreas superiores (IVAS), procedentes de uma creche e associar os dados clínicos e epidemiológicos da IVAS de grau leve com o agente viral. Foi realizado seguimento diário das crianças no período de julho de 2003 a julho de 2004 e investigação virológica para VSR através de Polimerase Chain Reaction (PCR), em secreções nasofaríngeas das crianças que apresentaram sinais de infecção respiratória. Ocorreram 259 episódios de IVAS em 173 crianças. Cento e vinte e duas (70,5%) crianças tinham mais de 2 anos de idade no início do segmento e 94 (54,3%) eram do sexo masculino. O número mensal de episódios variou de 0 a 53. O VSR foi diagnosticado em 27 (10,5%) amostras e foi mais freqüente nos meses de julho a setembro. Os sinais observados nas crianças com infecção por VSR foram coriza em 26 (96,3%) episódios, obstrução nasal em 19 (70,4%), tosse em 15 (55,6%),chiado em 3 (11,1%) e espirro e febre em 2 (7,4%) episódios. O uso de antibióticos ocorreu em 16 (6,2%) episódios de infecção respiratória. Um (3,7%) episódio de infecção por VSR recebeu tratamento com antibiótico. Houve 1 (0,4%) episódio grave que evoluiu para internação. Observou-se uma alta freqüência de VSR entre as crianças com infecções respiratórias leves, principalmente do início do outono ao início da primavera; os sinais mais freqüentes nas infecções por VSR foram tosse, coriza e obstrução nasal; houve associação entre obstrução nasal e infecções por VSR.
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Avaliação das infecções respiratórias virais em pacientes com fibrose cística / Respiratory viral infections evaluation in cystic fibrosis patients

Marina Buarque de Almeida 03 April 2010 (has links)
O objetivo deste estudo foi avaliar o impacto clínico, funcional e bacteriológico das infecções respiratórias virais nos pacientes com fibrose cística durante um ano. A identificação viral foi feita por métodos de biologia molecular para os seguintes virus: Vírus sincicial respiratório, Influenza A e B, Parainfluenza 1, 2 e 3, Adenovírus, Rinovírus, Metapneumovírus humano, Coronavírus, Enterovírus e Bocavírus. Foram 408 amostras com identificação viral em 199 amostras (48,7%). O Rinovírus foi o mais prevalente sendo identificado em 140 amostras (34,31%), mas contrastando com outros estudos em fibrose cística e em outras doenças pulmonares crônicas, o Rinovírus não mostrou ter impacto clínico, funcional ou bacteriológico significativo nos pacientes com fibrose cística / The objective of this study was to evaluate the clinical, functional and bacteriological impact of the viral respiratory tract infections in cystic fibrosis patients over one year. Viral identification was done through molecular biology methods for the following virus: Respiratory syncytial virus, Influenza A and B, Parainfluenza viruses type 1 to 3, Adenovirus, Rhinovirus, Human metapneumovirus, Coronavirus, Enterovirus and Human bocavirus. 199 (48,7%) samplings among 408 were positive for at least one virus. Rhinovirus was the virus with a higher prevalence, which was identified in 140 samplings (34,31%), but without clinical, functional or bacteriological impact contrasting with other studies in patients with cystic fibrosis and other chronic lung diseases

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