Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-01-05T12:06:12Z No. of bitstreams: 1 TeseLCS.pdf: 1420745 bytes, checksum: 4dd4fbff68d9aa7235de8b5f959ba86d (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2017-01-16T12:39:26Z (GMT) No. of bitstreams: 1 TeseLCS.pdf: 1420745 bytes, checksum: 4dd4fbff68d9aa7235de8b5f959ba86d (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2017-01-16T12:39:35Z (GMT) No. of bitstreams: 1 TeseLCS.pdf: 1420745 bytes, checksum: 4dd4fbff68d9aa7235de8b5f959ba86d (MD5) / Made available in DSpace on 2017-01-16T12:39:43Z (GMT). No. of bitstreams: 1 TeseLCS.pdf: 1420745 bytes, checksum: 4dd4fbff68d9aa7235de8b5f959ba86d (MD5) Previous issue date: 2016-07-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Viral hepatitis is a major public health problem worldwide and in Brazil. They are notifiable diseases and according to estimates, billions of people have had contact with the hepatitis and millions are chronic carriers. Infection with hepatitis C virus (VHC) is a major problem worldwide public health due to the high rate of progression to chronicity, the evolutionary potential for cirrhosis and hepatocellular carcinoma, major complications leading to death. In general it can be said that in the last decade there have been major advances in the diagnosis of hepatitis C. In this period there was progressive improvement in sensitivity and specificity of the tests used to detect antibodies against the VHC virus. However, it is necessary that more accurate tests are developed. Thus, considering that the concern for the detection of hepatitis C increases every day, especially in blood banks; the diagnostic methods of this infection are of great clinical relevance and may be used as markers chronicity and indicative of therapeutic efficacy. Therefore, this work proposed to evaluate the connection and recognition of anti-VHC antibody positive and positive genotyped samples in patients with hepatitis C through the standardization of procedures and solutions used in qualitative ELISA. There was the process of awareness of microplates with recombinant chimeric protein, made the analysis of sensitivity, specificity, reproducibility and validity of the method. We obtained from ELISA assays with standardized recombinant proteins a protocol able to have a good performance of the main components of the reaction, and antigens conjugated with good resolution. This study presented ELISA results valid 95.69%, 100% reproducibility, 94.5% sensitivity and specificity 99.3%, higher than the ELISA performed with multiepitopo protein MEHCV who presented with sensitivity (92.86%) and specificity (82.89%). The standard ELISA can be used as a qualitative serological technique aimed at detection of anti-VHC antibodies, as demonstrated with great reactivity in patients infected with VHC. / As hepatites virais são um grave problema de saúde pública no mundo e no Brasil. São doenças de notificação compulsória e segundo estimativas, bilhões de pessoas já tiveram contato com vírus das hepatites e milhões são portadores crônicos. A infecção pelo vírus da hepatite C (HCV) constitui um grave problema de saúde pública mundial devido à elevada taxa de progressão para cronicidade, ao potencial evolutivo para cirrose e carcinoma hepatocelular, principais complicações conducentes à morte. Em geral, pode-se dizer que na última década houve grandes avanços no diagnóstico da hepatite C. Nesse período houve progressiva melhora na sensibilidade e especificidade dos testes utilizados para detecção de anticorpos contra o vírus HCV. Contudo, é necessário que sejam desenvolvidos testes de maior acurácia. Assim, considerando que a preocupação com a detecção da hepatite C aumenta a cada dia, principalmente em bancos de sangue; os métodos diagnósticos desta infecção são de grande relevância clínica e podem ser utilizados como marcadores de cronicidade e indicativos da eficácia terapêutica. Portanto, esse trabalho propôs avaliar a ligação e reconhecimento dos anticorpos anti-HCV de amostras positivas e positivas genotipadas de pacientes portadores de Hepatite C, através da padronização dos procedimentos e soluções utilizadas no ELISA qualitativo. Realizou-se o processo de sensibilização das microplacas com proteína recombinante quimérica, fez-se a análise da sensibilidade, especificidade, reprodutibilidade e validade do método. Obtivemos a partir dos ensaios de padronização do ELISA com proteínas recombinantes um protocolo capaz de ter um bom rendimento dos principais componentes da reação, antígenos e conjugado, com boa resolução. O presente estudo apresentou-se resultados do ELISA com validade 95,69% , reprodutibilidade 100%, sensibilidade 94,5% e especificidade 99,3%, superior ao ELISA realizado com a proteína multiepitopo MEHCV que apresentaram com sensibilidade (92,86%) e especificidade (82,89%). O ELISA padronizado pode ser utilizado como uma técnica sorológica qualitativa, visando a detecção de anticorpos anti-HCV, pois mostrou-se com ótima reatividade nos soros pacientes infectados com HCV.

Made available in DSpace on 2014-06-11T19:27:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-27Bitstream added on 2014-06-13T19:56:29Z : No. of bitstreams: 1 souza_np_me_araca_parcial.pdf: 84559 bytes, checksum: a91c08079d17881af80d81ddcd410ea2 (MD5) Bitstreams deleted on 2015-04-13T18:26:30Z: 000717296_20161201.pdf,Bitstream added on 2015-04-13T18:27:08Z : No. of bitstreams: 1 000717296_20161201.pdf: 106851 bytes, checksum: 12763ba93fc326e41a47c3b9825c8add (MD5) Bitstreams deleted on 2016-12-02T12:41:54Z: 000717296_20161201.pdf,. Added 1 bitstream(s) on 2016-12-02T12:42:34Z : No. of bitstreams: 1 000717296.pdf: 791335 bytes, checksum: 51138541e37fde8cbfc7d4fece13e8c1 (MD5) / Item merged in doublecheck by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-12-02T12:40:37Z Item was identical to item(s): 94531, 123590 at handle(s): http://hdl.handle.net/11449/95395, http://hdl.handle.net/11449/124512 / É crescente o número de pessoas acometidas por doenças crônicas, dentre elas, as doenças hepáticas, que são consideradas um problema de saúde pública mundial. A hepatite C é uma das principais causas de doenças hepáticas crônicas (DHC), acarretando impacto negativo sobre a qualidade de vida (QV). Por essas razões, o objetivo deste estudo foi realizar uma revisão bibliográfica dos principais aspectos relacionados com o vírus da hepatite C (VHC), e avaliar a qualidade de vida dos indivíduos portadores de DHC. A revisão de literatura foi realizada nas seguintes bases de dados: Medline, ISI - Web of Science, Lilacs, Pubmed e Scielo, sem restrições de data de publicação ou idioma. Para avaliar a qualidade de vida foi realizado um estudo transversal, com 133 pacientes com diagnóstico de DHC, de ambos os sexos, com idade superior a 18 anos. Após a obtenção do termo de consentimento livre e esclarecido foram aplicados três instrumentos de pesquisa. O primeiro referiu-se ao questionário através do qual os participantes foram entrevistados sobre as características sociodemográficas. O segundo instrumento utilizado foi o Chronic Liver Disease Questionnaire (CLDQ), instrumento recentemente traduzido e validado para a população brasileira o qual possui a finalidade de mensurar a qualidade de vida dos pacientes portadores de hepatopatias. O CLDQ é constituído por 29 questões distribuídas em 6 domínios que referem-se aos seguintes sintomas da doença: Sintomas Abdominais (SA); Fadiga (FA), Sintomas Sistêmicos (SS), Atividade (AT), Emoção (EM) e Preocupação (PR). A gravidade da doença hepática foi avaliada de acordo com o terceiro instrumento, o escore validado MELD (Model End-Stage Liver Disease). As variáveis... / Is increasing the number of people affected by chronic diseases, among them, liver diseases, that are considered as public health problem round the world. Hepatitis C is one of the most principal reasons for chronic liver diseases (CLD), causing negative impact on quality of life (QOL). Thus, the aim of this study was realize a review of the main aspects related to hepatitis C virus (HCV), and to evaluate the quality of life of individuals with CLD. The review was performed on the data bases: Medline, ISI – Web of Science, Lilacs, Pubmed and Scielo, without restrictions about data or idiom. To evaluate the quality of life it was realized a cross-sectional study with 133 patients with CLD, both genders, older than 18 years old. After have had the Free and Clear Consent Term assigned, it was applied three instruments. The first referred to social and demographic features. The second was the Chronic Liver Disease Questionnaire (CLDQ) that was recently translated and validated for the Brazilians, and its aim is to measure the quality of life of patients with liver diseases. The CLDQ contain 29 questions distributed in 6 domains about the follow diseases: Abdominal Symptoms (AS); Fatigue (FA), Systemic Symptoms (SY), Activity (AC), Emotion (EM) and Worry (WO). The severity of liver disease was evaluated according to the third instrument, the score validated MELD (Model End-Stage Liver Disease). The categorical variables were shown by frequency and percentages, and the continuous, average and standard deviation. To evaluate the difference between the score average of CLDQ between genders it was used Student Test... (Complete abstract click electronic access below)

Orientador: Rejane Maria Tommasini Grotto / Coorientador: Maria de Moura Campos Pardini / Banca: Giovanni Faria Silva / Banca: Ana Flavia Nacif Pinto coelho Pires / Resumo: A detecção do RNA viral do VHC tem sido documentada em outros compartimentos biológicos além do soro e plasma de pacientes infectados pelo vírus, como nas plaquetas. No entanto, sua influência na terapia antiviral é desconhecida. Poucos estudos têm sido realizados na tentativa de avaliar a quantificação do RNA viral em outros compartimentos biológicos e a significância deste achado no resultado da terapia antiviral. Considerando que o VHC é carreado pelas plaquetas na circulação, a avaliação quantitativa do RNA viral neste compartimento biológico pode se mostrar distinta da observada no plasma.Realizar a avaliação comparativa in vitro do RNA do VHC plasmático e do RNA do VHC carreado à plaqueta e, realizar a avaliação comparativa da quantificação do RNA viral do VHC em plasma e plaquetas de pacientes com recidiva ao tratamento antiviral.Amostras de sangue periférico provenientes de pacientes infectados pelo VHC foram utilizadas para realização de dois experimentos. Experimento in vitro (repetido em triplicata) consistiu na separação de quatro alíquotas da mesma amostra, as quais foram submetidas a incubação a 37oC por 30xg por diferentes intervalos de tempo (0, 48, 96, 144h) e, posteriormente separadas para obtenção de plasma e pellet de plaquetas. A partir de cada uma destas frações foi extraído RNA viral, o qual foi utilizado como fonte para qPCR. Experimento in vivo: Foram acompanhados pacientes que iniciaram e finalizaram a terapêutica entre janeiro de 2011 a julho de 2012 e, dentre estes, os que apresentaram recidiva virológica ao tratamento antiviral estabelecido. Dos pacientes em recidiva virológica foram processadas amostras para a obtenção do plasma e pellet de plaquetas em dois momentos: no momento da recidiva virológica e, no momento imediatamente anterior (12 semanas anteriores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Treatment for chronic hepatitis C is effective in about 50% of patients treated with exogenous interferon, which induces interferon-stimulated genes leading to endogenous interferon production. Integrins are involved in interferon production and structural modifications of them can be associated with altered function. Some integrins, expressed on the platelet membrane, show polymorphic antigenic determinants called human platelet antigens (HPA). The association between HCV infection and HPA-5b has already been demonstrated, in the same way the HPA profile could be associated with therapeutic response. This study aimed evaluates the association between the HPA-1, -3, -5 frequencies and therapy response in HCV-infected patients. HPA genotyping was performed in 168 HCV-infected patients by PCRSSP or PCR-RFLP. The patients were on interferon- (48.8%: 43.9% carriers of HCV genotype 1 and 56.1% non-1) or peginterferon (51.2%; 87.2% carriers of HCV genotype 1 and 12.8% non-1), both combined with ribavirin. Statistical analysis was performed using the proportional odds model. The genotypic frequency of HPA-1a/1b was significantly higher in the patients with therapeutic failure (odds ratio=3.58, 95% CI -1.18 - 10.82). The results suggest that the HPA-1a/1b genotype is associated with therapy failure... (Complete abstract click electronic access below) / Mestre

Orientador : Paulo Inácio da Costa / Coorientador: Luiz Marcos da Fonseca / Banca: Alexandra Ivo de Medeiros / Banca: Cleslei Fernando Zanelli / Banca: Marcelo Dias Baruffi / Banca: Amanda Martins Baviera / Resumo: Aproximadamente 170 milhões de pessoas no mundo estão cronicamente infectadas pelo vírus da Hepatite C (HCV). No Brasil, os números já chegam a 3 milhões. A persistência da infecção pelo HCV no fígado leva à cronificação da doença, cirrose e hepatocarcinoma. A proteína de envelope 2 (E2) do HCV é a responsável pelo seu acoplamento à célula hospedeira através da interação com receptores de superfície celular, como o R-LDL e o CD81, entre outros. Como as alterações na micro e macrovasculatura hepática, têm sido apontadas como elementos fundamentais na histogênese e prognóstico da doença, o objetivo deste estudo foi avaliar a interação da proteína E2 recombinante com os R-LDL presentes na superfície de células endoteliais (ECV304 e HUVEC) sob influência de LDL e da glicosilação protéica. Também avaliar a resposta inflamatória das células endoteliais à interação com estas proteínas. A proteína E2 foi expressa em dois sistemas heterólogos, E. coli e P. pastoris, para avaliação da glicosilação e da interação com LDL na ligação aos R-LDL das células através de citometria de fluxo. As proteínas também foram avaliadas em testes biológicos quanto à indução celular de produção de espécies reativas de oxigênio (EROs totais - QL e H2O2 - citometria de fluxo), NO (QL em fase gasosa e por método de Griess), arginase (espectrofotometria), IL-8 (ELISA), VEGF (ELISA) e morte celular (MTT - espectrofotometria e por anexina V e PI - citometria de fluxo). Os resultados obtidos revelaram que as proteínas E2 recombinantes podem interagir com os R-LDL das células endoteliais após a ligação ao LDL e que esta ligação pode ser melhorada pela glicosilação (E2L) (p<0,01 em relação à E2B). O teste de NO indicou que as proteínas glicosiladas exibem maior potencial para o estímulo deste nas células HUVEC (p<0,01 em relação ao controle negativo). As concentrações de proteínas testadas não ... / Abstract: Approximately 170 million people worldwide are chronically infected with hepatitis C virus (HCV). In Brazil, the numbers have already reached 3 million. The persistence of HCV infection leads to chronic infection in liver disease, cirrhosis and hepatocellular carcinoma. The envelope protein 2 (E2) of HCV is responsible for its coupling to the host cell through interaction with cell surface receptors such as the R-LDL and CD81, among others. Because changes in micro and macrovasculature liver, have been identified as key elements in the histogenesis and prognosis of the disease, the aim of this study was to evaluate the interaction of the protein E2 recombinant with the R-LDL present on the surface of endothelial cells (HUVEC and ECV304) under the influence of LDL and protein glycosylation. And also evaluate the inflammatory response of endothelial cells to interact with these proteins. The E2 protein was expressed in two heterologous systems, E. coli and P. pastoris for evaluation of glycosylation and interaction with LDL binding to the R-LDL cells by flow cytometry. The proteins were also evaluated in biological tests for induction of cellular production of reactive oxygen species (EROs - QL and H2O2 - flow cytometry), NO (QL in doing gas and Griess Reagent), arginase (spectrophotometry), IL-8 (ELISA), VEGF (ELISA) and cell death (MTT - spectrophotometry and Annexin V and PI - flow cytometry). The results obtained showed that the recombinant E2 protein can interact with R-LDL endothelial cell after binding to LDL and that this binding can be enhanced by glycosylation (E2L) (p <0.01 in relation to E2B). The NO test indicated that glycosylated proteins exhibit greater potential for the stimulation of the HUVEC cells (p <0.01 compared with negative control). Protein concentrations tested were not sufficient to stimulate an increase or decrease in the activity of arginase remarkable compared to the negative control. The recombinant protein ... / Doutor

Resumo: O presente estudo teve por objetivo descrever características sóciodemográficas, psicossociais, clínicas, índices de qualidade de vida, ocorrência de transtorno mental comum, de sintomas depressivos de pacientes portadores de Hepatite C crônica, em tratamento no Ambulatório de Hepatites Virais da Disciplina de Gastroenterologia Clínica do HC da FMB-UNESP, em três momentos de seu tratamento com Interferon Peguilado e Ribavirina: antes do início, nas 12ª e 24ª semanas de tratamento. Foram também estudadas as associações das variáveis sócio-demográficas e clínicas, de transtorno mental comum (TMC), sintomas depressivos, da forma de tratamento com índices de qualidade de vida (QV) nos três momentos estudados e com os resultados de exames indicativos da resposta virológica ao tratamento (detecção do RNA do vírus da Hepatite C pelo método de PCR). Método: Realizou-se estudo transversal e de seguimento. Uma amostra de conveniência foi estabelecida, tendo-se estudado 82 pacientes no estudo transversal e feito o seguimento de 46 no terceiro e sexto mês após o início do tratamento. Utilizou-se formulário estruturado para investigar aspectos sócio-demográficos e clínicos. Sintomas depressivos foram avaliados pelo Beck Depression Inventory (BDI). Utilizou-se o Self Reporting Questionnaire (SRQ) para avaliar Transtorno Mental Comum e o uso nocivo de álcool foi avaliado por meio do Alcohol Use Disorders Identification Test (AUDIT). A qualidade de vida foi estudada por meio do The Medical Outcomes Study 36 item Short-Form Health Survey (SF-36). O estudo das associações entre variáveis categoriais foi feito pelo teste do Qui-quadrado (ou Fisher, se adequado). Os Testes de Mann-Whitney e de Kruskal Wallis foram utilizados para comparar as distribuições dos vários domínios do SF-36. Para comparação entre os dados nos momentos subseqüentes foram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed at describing socio-demographic, psychosocial and clinical characteristics as well as quality of life indexes, occurrence of common mental disorder and depressive symptoms of patients with chronic hepatitis C undergoing treatment at the Viral Hepatitis Outpatient Unit of the Botucatu Medical School - UNESP, at three different moments of their treatment with Peguilated Interferon and Ribavirin: immediately before treatment, 12 and 24 weeks after its introduction. The association of socio-demographic and clinical variables as well as those for common mental disorder (CMD), depression symptoms and form of treatment with quality-of-life (QL) indexes was evaluated at the three studied moments. The association of such variables with test results indicating virological response to treatment (detection of the hepatitis C virus RNA by the PCR method) was also investigated. Method: A convenience sample was established, and 82 patients were studied in a cross-sectional and follow-up investigation. Forty-six patients were followed 3 and 6 months after the beginning of treatment. A structured questionnaire was used to investigate socio-demographic and clinical aspects. Depression symptoms were evaluated by the Beck Depression Inventory (BDI). The Self Reporting Questionnaire (SRQ) was utilized to evaluate common mental disorder, and harmful use of alcohol was evaluated by the Alcohol Use Disorders Identification Test (AUDIT). Quality of life was assessed by the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36). The study of the associations between categorial variables was performed by the chi-square test (or Fisher, if adequate). The Mann-Whitney and Kruskal Wallis tests were used to compare the distribution of various domains of SF-36. McNemar's Exact Test was used for category variables to compare the data at the subsequent moments, and Friedman's Test was... (Complete abstract click electronic access below) / Orientador: Ana Teresa de Abreu Ramos-Cerqueira / Coorientador: Giovanni Faria Silva / Banca: Fani Eta Korn Malerbi / Banca: Carlos Antonio Caramori / Mestre

Orientador: Cléa Adas Saliba Garbin / Coorientador: Lívia Melo Villar / Banca: Dóris Hissako Sumida / Banca: Patrícia Elaine Gonçalves / Resumo: É crescente o número de pessoas acometidas por doenças crônicas, dentre elas, as doenças hepáticas, que são consideradas um problema de saúde pública mundial. A hepatite C é uma das principais causas de doenças hepáticas crônicas (DHC), acarretando impacto negativo sobre a qualidade de vida (QV). Por essas razões, o objetivo deste estudo foi realizar uma revisão bibliográfica dos principais aspectos relacionados com o vírus da hepatite C (VHC), e avaliar a qualidade de vida dos indivíduos portadores de DHC. A revisão de literatura foi realizada nas seguintes bases de dados: Medline, ISI - Web of Science, Lilacs, Pubmed e Scielo, sem restrições de data de publicação ou idioma. Para avaliar a qualidade de vida foi realizado um estudo transversal, com 133 pacientes com diagnóstico de DHC, de ambos os sexos, com idade superior a 18 anos. Após a obtenção do termo de consentimento livre e esclarecido foram aplicados três instrumentos de pesquisa. O primeiro referiu-se ao questionário através do qual os participantes foram entrevistados sobre as características sociodemográficas. O segundo instrumento utilizado foi o Chronic Liver Disease Questionnaire (CLDQ), instrumento recentemente traduzido e validado para a população brasileira o qual possui a finalidade de mensurar a qualidade de vida dos pacientes portadores de hepatopatias. O CLDQ é constituído por 29 questões distribuídas em 6 domínios que referem-se aos seguintes sintomas da doença: Sintomas Abdominais (SA); Fadiga (FA), Sintomas Sistêmicos (SS), Atividade (AT), Emoção (EM) e Preocupação (PR). A gravidade da doença hepática foi avaliada de acordo com o terceiro instrumento, o escore validado MELD (Model End-Stage Liver Disease). As variáveis... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Is increasing the number of people affected by chronic diseases, among them, liver diseases, that are considered as public health problem round the world. Hepatitis C is one of the most principal reasons for chronic liver diseases (CLD), causing negative impact on quality of life (QOL). Thus, the aim of this study was realize a review of the main aspects related to hepatitis C virus (HCV), and to evaluate the quality of life of individuals with CLD. The review was performed on the data bases: Medline, ISI - Web of Science, Lilacs, Pubmed and Scielo, without restrictions about data or idiom. To evaluate the quality of life it was realized a cross-sectional study with 133 patients with CLD, both genders, older than 18 years old. After have had the Free and Clear Consent Term assigned, it was applied three instruments. The first referred to social and demographic features. The second was the Chronic Liver Disease Questionnaire (CLDQ) that was recently translated and validated for the Brazilians, and its aim is to measure the quality of life of patients with liver diseases. The CLDQ contain 29 questions distributed in 6 domains about the follow diseases: Abdominal Symptoms (AS); Fatigue (FA), Systemic Symptoms (SY), Activity (AC), Emotion (EM) and Worry (WO). The severity of liver disease was evaluated according to the third instrument, the score validated MELD (Model End-Stage Liver Disease). The categorical variables were shown by frequency and percentages, and the continuous, average and standard deviation. To evaluate the difference between the score average of CLDQ between genders it was used Student Test... (Complete abstract click electronic access below) / Mestre

Introdução: A estimativa de sobrevida de pacientes com HIV/aids aumentou após a terapia antirretroviral de alta potência: no entanto, a mortalidade por doenças hepáticas também cresceu. Objetivos: Estimar a probabilidade acumulada de sobrevida após o diagnóstico de aids entre pacientes coinfectados HIV/HCV e realizar análise exploratória para investigar fatores relacionados à sobrevida desses pacientes. Metodologia: Estudo de coorte não concorrente, utilizando sistemas de Informações: o de Agravos de Notificação, o de informação laboratorial e o de informação da vigilância epidemiológica do Centro de Referência e Treinamento DST/AIDS-SP, de pacientes com aids maiores de 13 anos, acompanhados no ambulatório geral. As variáveis estudadas foram: hepatite C, hepatite B, categoria de exposição, contagem de células T CD4+, faixa etária, escolaridade, cor, sexo e períodos de diagnóstico de aids: 1986 a 1993, 1994 a 1996, 1997 a 2002 e 2003 a 2010. Foi utilizado o estimador de Kaplan-Meier, o modelo de Cox e as estimativas das hazard ratio (HR) com os respectivos intervalos de confiança (IC 95 por cento ). Resultados: De um total de 2.864 pessoas incluídas, com idade mediana de 35 anos, 219 foram a óbito (7,5 por cento ). De 358 (12,5 por cento ) coinfectados, 159 (45,1 por cento ) eram usuários de drogas injetáveis (UDI) e de 2.506 não coinfectados, 96 (3,9 por cento ) eram UDI. A probabilidade acumulada de sobrevida entre coinfectados, a partir do diagnóstico de aids, foi 100 por cento aos 60 meses no período de 1986 a 1993; 27,8 por cento aos 168 meses no período de 1994 a 1996; 76,3 por cento aos 168 meses no período de 1997 a 2002 e 92,8 por cento aos 96 meses no período de 2003 a 2010. As curvas de sobrevida foram diferentes entre coinfectados e não coinfectados no período de 1994 a 1996 (log rank = 19,8; p < 0,001) e no período de 1997 a 2002 (log rank = 38,8; p < 0,001). No modelo de Cox multivariado, mostraram-se preditores de óbito, independentemente das outras variáveis: ter hepatite C (HR = 2,9; IC 2,1-3,9), ter hepatite B (HR = 2,5; IC 1,7-3,6), ter até 3 anos de estudo (HR = 2,3; IC 1,5-3,6), ter 50 anos ou mais de idade (HR = 2,1; IC 1,3-3,2). Ter diagnóstico de aids no período entre 1997 a 2002 mostrou-se fator de proteção ao óbito (HR = 0,4; IC 0,3-0,5). Conclusões: Coinfectados HIV/HCV apresentaram menor sobrevida quando comparado com não coinfectados nos períodos de diagnóstico de aids 1994 a 1996 e 1997 a 2002. A partir do período 1994 a 1996, observou-se aumento significativo na probabilidade acumulada de sobrevida entre coinfectados, sendo que no período 2003 a 2010, essa probabilidade foi semelhante entre coinfectados e não coinfectados, refletindo possível impacto do tratamento da hepatite C / Introduction: The estimated survival of patients with HIV/AIDS has increased after highly active antiretroviral therapy; mortality due to liver diseases, however, has also increased. Objectives: To estimate the accumulated probability of survival after AIDS diagnosis among HIV/HCV co-infected individuals and to perform an exploratory analysis to investigate factors related to the survival of these patients. Method: Non-concurrent cohort study, using data from the National Disease Reporting Information System, the laboratory and epidemiological surveillance information systems of the SP-STD Reference and Training Center-CRT, of patients over 13 years of age, followed at the general outpatient clinic. The following variables were studied: hepatitis C, hepatitis B, exposure category, T CD4+ cell count, age group, schooling, color, sex, and AIDS diagnostic periods: 1986 to 1993, 1994 to 1996, 1997 to 2002 and 2003 to 2010. Survival analysis was performed using the Kaplan-Meier estimator and the Cox model, with estimates of the hazard ratio (HR) and respective confidence intervals (95 per cent CI). Results: Of a total of 2,864 individuals included, with a median age of 35 years, 219 died (7.5 per cent ). Of the 358 (12.5 per cent ) HIV/HCV co-infected individuals, 159 (45.1 per cent ) were injecting drug users (IDU), and of the non-co-infected 2,506, 96 (3.9 per cent ) were IDU. The accumulated probability of survival among HIV/HCV co-infected individuals at 60, 168, 168 and 96 months as of AIDS diagnosis, was 100 per cent in the 1986 -1993 period; 27,8 per cent in the 1994-1996 period; 76,3 per cent in the 1997-2002 period; and 92,8 per cent in the 2003-2010 period. The survival curves were different between co-infected and non-co-infected individuals in the 1994-1996 (log rank = 19,8; p < 0,001) and in the 1997-2002 (log rank = 38,8; p < 0,001). In the multivariate model, regardless of other variables, the following were predictors of death: having hepatitis C (HR = 2.9; CI 2.1-3.9); having hepatitis B (HR = 2.5; CI 1.7-3.6); being 50 years old or over (HR = 2.1; CI 1.3-3.2) and having up to 3 years of schooling (HR = 2.3; CI 1.5-3.6). AIDS diagnosis between 1997 and 2010 was shown to be a protective factor for death (HR = 0.4; CI 0.3-0.5). Conclusions: HIV/HCV co-infected individuals had shorter survival, when compared to non-co-infected individuals in the 1994-1996 and in the 1997-2002 AIDS diagnostic periods. As of the 1994-1996 period, a significant increase in the accumulated probability of survival among HIV/HCV co-infected individuals was observed. In the 2003-2010 period, the probability was similar between co-infected and non-coinfected individuals, showing the possible impact of hepatitis treatment

L’infection par le Virus de l’Hépatite C (VHC) est un problème majeur de santépublique touchant environ 170 millions de personnes dans le monde. A l’heure actuelle, il n’existe aucun vaccin pour lutter contre le VHC et les traitements curatifs disponibles sont chers, donnent lieu à des effets secondaires très sévères et ne sont efficaces que pour une partie des patients. Le développement de nouvelles stratégies antivirales représente donc un enjeu crucial dans la lutte contre le VHC. Dans le but de développer de nouvelles molécules bloquant différentes étapes du cycle viral, une meilleure compréhension de chacune des ces étapes est nécessaire. Au cours de mon travail de thèse, nous avons étudier le mécanisme d’entrée du VHC dans ses cellules cibles, les hépatocytes. Dans un premier temps nous avons caractérisé un inhibiteur naturel de l’entrée du VHC, appelé EWI-2wint. Ce travail a notamment permis de mettre en évidence l’importance de la dynamique membranaire de l’un des récepteurs du virus, la protéine CD81, dans ce processus. Dans un second axe, nous avons étudié l’effet de la monensine sur l’infection par le VHC. Nous avons ainsi montré que cet inhibiteur pharmacologique bloque une étape tardive du processus d’entrée du VHC.L’ensemble des données accumulées au cours de ma thèse permettent de mieux comprendre le mécanisme d’entrée du VHC et ouvrent la voie au développement de nouveaux outils thérapeutiques. / Hepatitis C, whose causal agent is called Hepatitis C Virus (HCV), is a global health burden with about 170 million people infected. Currently, no vaccine exists again HCV and treatments are effective for only a part of infected people. Therefore, new treatments are urgently needed, as well as a better understanding of the viral life cycle.To do so, we studied the entry process of HCV in its targets cells through the characterisation of HCV entry inhibitors. Firstly, we have shown that EWI-2wint, a natural inhibitor of HCV entry, blocks this process by changing the partitionning of CD81, one of the HCV receptors. In addition, we have studied the effect of monensin on HCV infection and found that this pharmacological inhibitor impairs a late step of HCV entry.Altogether, our results allow a better understading of the HCV entry process and open the way to the development of new therapeutic agents.

Hepatitis C virus (HCV), a blood-borne pathogen, is a small enveloped RNA virus belonging to the Hepacivirus genus of the Flaviviridae family. HCV infection represents one of the major health concerns affecting approximately 170 million people globally. Patients with chronic HCV infection are at risk of developing hepatic fibrosis, cirrhosis and hepatocellular carcinoma. No protective anti-HCV vaccine is available yet. Until recently, standard therapy based on pegylated interferon plus ribavirin, was inadequate in treating all the patients as it results in a sustained virological response in only 40 to 50 percent of patients infected with the most common genotype (gt 1). Advances in understanding host-HCV interactions have helped developing newer anti-HCV agents such as telaprevir and boceprevir. However, treatment success is still limited due to different factors including genotype specificity, high cost, potential drug-drug interactions, substantial side effects etc. The positive-sense single-stranded RNA genome of HCV is approximately 9.6kb long which is flanked by highly structured and conserved 5’ and 3’ untranslated regions (UTRs) at both ends. Unlike cap-dependent translation of host cell mRNAs, HCV translation is mediated by an internal ribosomal entry site (IRES) present majorly within the 5’UTR. Several reports have demonstrated the interaction of different cellular proteins with HCV-5’UTR and/or 3’UTR, which include human La protein, polypyrimidine tract binding protein (PTB), poly (rC)-binding protein 2 (PCBP2) etc. These interactions of trans-acting factors with the UTRs may be important for HCV translation and/or replication. Earlier study from our laboratory revealed the importance of interaction of human La protein, by its central RNA recognition motif (RRM), with the HCV IRES around a tetranucleotide sequence GCAC near initiator AUG in influencing HCV translation. However, the role of this interaction, if any, in HCV RNA replication was not known. In the first part of the thesis, we characterized the interaction between human La protein and the GCAC to understand its role in HCV replication. We incorporated mutation, which altered the binding of La, in the GCAC motif in HCV monocistronic replicon and checked HCV RNA replication by reverse transcriptase polymerase chain reaction (RT-PCR). The mutation drastically inhibited HCV replication. Interestingly, overexpression of La could reverse the effect of this mutation and significantly enhanced HCV RNA levels. Using a bicistronic replicon, we observed that decrease in replication was independent of translation inhibition. Furthermore, mutation at the GCAC motif reduced the association between La and viral polymerase, NS5B as seen in co-immunoprecipitation assays. Moreover, this mutation affected translation to replication switch regulated by the interplay between HCV-NS3 protease and human La protein. Our analyses of point mutations, based on RT-PCR and luciferase assays, revealed distinct roles of each nucleotide of the GCAC motif in HCV replication and translation. Finally, 5’-3’ crosslink assays revealed that specific interaction of the GCAC motif with human La protein is important for linking 5’ and 3’ends of HCV genome. Results clearly demonstrate the mechanism of regulation of HCV replication by interaction of cis-acting element GCAC within the HCV IRES with human La protein. HCV is highly species-specific. Under natural conditions, HCV infects only humans and chimpanzees. This restricted host-tropism has prevented the development of a small animal model to study HCV infection in vivo. Although several human-specific entry factors have been identified to be responsible for this species selectivity, full multiplication of the HCV in animals (other than humans and chimpanzees) is still not possible. In the second part of the thesis, we showed that a post-entry host factor –‘La protein’ may also contribute in determining HCV host tropism. We aligned La protein sequences from different species and interestingly we found that HCV RNA interacting beta-turn sequence (KYKETDL) in central RRM (residues 112-184) is conserved only in human and chimpanzee. Earlier, it was shown from our laboratory that a heptameric peptide comprising of this sequence (derived from human La) could inhibit HCV translation by competing with La interaction with the IRES element. However, in the current study, another peptide corresponding to the mouse La sequence (KYKDTNL) was unable to inhibit HCV RNA translation. Similarly, wild-type mouse La (mLa) failed to stimulate HCV IRES function, but addition of chimeric mouse La protein bearing human beta-turn sequence (mLahN7) significantly increased HCV IRES mediated translation in vitro. Also, exogenous supplementation of mLahN7 enhanced HCV translation in cell culture system. Moreover, quantitative as well as tagged RT-PCR analyses showed an enhanced HCV replication upon overexpression of mLahN7. The findings obtained in this part raise a possibility of creating HCV mouse model using human specific cellular entry factors and a humanized form of La protein. Hepatitis C has emerged as a major challenge to the medical community. Developing more potent and safe anti-HCV regimens is need of the hour. As described above, a linear hepatapeptide (KYKETDL) was synthesized and shown to reduce HCV translation. However, this linear peptide was stable only for a shorter time scale. Therefore, in the third part of the thesis, effect of a more stable cyclic form of this peptide has been described. NMR spectroscopy suggested that the beta turn conformation is preserved in cyclic peptide as well. Also, using in vitro bicistronic reporter assay, we demonstrated that cyclic peptide inhibits HCV translation in a dose dependent manner. In fact, due to its higher stability, cyclic peptide reduced HCV translation and replication more efficiently than the corresponding linear peptide at longer post-treatment time point. Additionally, we observed that cyclic peptide is non-toxic in cell culture system. Our results suggest that cyclic peptide might emerge as a promising lead compound against hepatitis C. Due to availability of only partially effective liver protective drugs in modem medicine, complementary and alternative medicine approach, based on plant derived compounds, is also being utilised against HCV. Plant derived compounds have advantages of having high chemical diversity, drug-likeliness properties and ability of being metabolized by the body with little or no toxicity than synthetic ones. Different studies have shown that phytochemicals may exert anti-HCV activities by acting as direct-acting antivirals and play a potential therapeutic role in treating HCV infection. Also, from our laboratory, it was shown that methanolic extract of Phyllanthus amarus (P. amarus) plant inhibited HCV replication. The fourth part of the thesis describes the study on the anti-HCV properties of several bioactive components from P. amarus extract. Using a fluorimetric assay, we demonstrated that two principal components of this extract, phyllanthin and corilagin reduced the HCV NS3 protease activity significantly in vitro. We also observed a sharp reduction in HCV negative sense RNA levels in cell culture system. Structural knowledge-based molecular docking studies showed interactions of phyllanthin and corilagin with the amino acid residues of the catalytic triad of NS3 protease. Further, these compounds were found to be non-toxic in cell culture. Also, phyllanthin and corilagin displayed antioxidant properties by blocking HCV induced oxidative stress generated by reactive oxygen species suggesting their hepatoprotective nature. More importantly, our in vivo toxicity analyses and pharmacokinetics studies proved their safety, tolerability, metabolic stability, and systemic oral bioavailability and support their potential as novel anti-HCV therapeutic candidates. Altogether, the study deciphers mechanistic details of translation and replication of HCV RNA and demonstrates novel antiviral agents targeting these important viral processes.

The current treatment for hepatitis C virus (HCV) infection – combination therapy with pegylated interferon and ribavirin – elicits sustained responses in only ~50% of the patients treated. Greater cumulative exposure to ribavirin increases response to interferon-ribavirin combination therapy. A key limitation, however, is the toxic sideeffect of ribavirin, hemolytic anemia, which often necessitates a reduction of ribavirin dosage and compromises treatment response. Maximizing treatment response thus requires striking a balance between the antiviral and hemolytic activities of ribavirin. Current models of viral kinetics describe the enhancement of treatment response due to ribavirin. Ribavirin-induced anemia, however, remains poorly understood and precludes rational optimization of combination therapy. Here, we develop a new mathematical model of the population dynamics of erythrocytes that quantitatively describes ribavirin-induced anemia in HCV patients. Based on the assumption that ribavirin accumulation decreases erythrocyte lifespan in a dose-dependent manner, model predictions capture several independent experimental observations of the accumulation of ribavirin in erythrocytes and the resulting decline of hemoglobin in HCV patients undergoing combination therapy, estimate the reduced erythrocyte lifespan in patients and describe inter-patient variations in the severity of ribavirin-induced anemia. Further, model predictions estimate the threshold ribavirin exposure beyond which anemia becomes intolerable and suggest guidelines for the usage of growth hormones. A small fraction of the population (~30%) with polymorphisms in the ITPA gene shows protection from ribavirin-induced anemia. The optimum dosage of ribavirin that can be tolerated is then dependent on the ITPA polymorphisms. Coupled with a previous population pharmacokinetic study, our model yields a facile formula for estimating the optimum dosage given a patient’s weight, creatinine clearance, pretreatment hemoglobin levels, and ITPA polymorphism. The reduced lifespan we predict is in agreement with independent measurements from breath tests as well as estimates derived from in vitro studies of ATP depletion. The latter estimates also agree with the extent of ATP depletion due to ribavirin that we predict from a detailed analysis of the nucleoside metabolism in erythrocytes. Our model thus facilitates in conjunction with models of viral kinetics the rational identification of treatment protocols. Our formula for optimum dose presents an avenue for personalizing ribavirin dosage. By keeping anemia tolerable, the predicted optimal dosage may improve adherence, reduce the need for drug monitoring, and increase response rates.