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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.
11

Avaliação in vitro do efeito da cafeína na inibição do vírus da Hepatite C /

Batista, Mariana Nogueira. January 2014 (has links)
Orientador: Paula Rahal / Coorientador: Bruno Moreira Carneiro / Banca: Laura Cristina Sichero Vetorazzo / Banca: Maurício Lacerda Nogueira / Resumo: A hepatite C é a inflamação do fígado decorrente da infecção pelo vírus da hepatite C (HCV), frequentemente evolui para quadros crônicos, sendo considerada mundialmente a maior causa de cirrose e carcinoma hepatocelular. O tratamento padrão com PEG-IFN e ribavirina não é efetivo contra alguns genótipos do HCV, possui alto custo e efeitos colaterais severos. Portanto, novos tratamentos vêm sendo buscados. A cafeína vem sendo associada a um efeito benéfico sobre várias doenças hepáticas incluindo a melhora da bioquímica anormal do fígado, cirrose e carcinoma hepatocelular. A cafeína atua diretamente desacelerando a progressão da fibrose, além de melhorar a função de vias celulares hepáticas, dentre elas vias utilizadas durante o ciclo replicativo do HCV. Embora a cafeína tenha demonstrado efetividade no controle de doenças hepáticas e interação direta com vias celulares utilizadas pelo HCV, não há na literatura correlação direta entre o efeito da cafeína e as etapas do ciclo replicativo do HCV. Assim, o presente estudo propôs estabelecer a relação direta entre a cafeína e sua capacidade inibitória sobre as diferentes etapas do ciclo replicativo completo do HCV. Para esse estudo foram utilizados o replicon subgenômico SGR-JFH-FEO, os replicons completos FL-J6/JFH-5′C19Rluc2AUbi e JFH-1 e a linhagem celular Huh-7.5. A expressão viral foi avaliada por ensaios de Luciferase, Western Blotting, Imunofluorescencia indireta e qPCR. A cafeína demonstrou inibição da replicação viral em todos os níveis avaliados, apresentando IC50 de 0.7263 mM e atingindo em concentrações seguras, inibição máxima da replicação de HCVcc em torno de 79 %. A cafeína demonstrou ainda inibição de 30 % sobre a entrada quando aplicada em conjunto ao sobrenadante infeccioso. Entretanto, essa inibição dobra quando há a exposição das partículas à cafeína previamente à introdução em cultura de células, ... / Abstract: Hepatitis C is the liver inflammation arising from hepatitis C virus (HCV) infection, often evolves to chronic conditions and has been considered the major world cause of cirrhosis and hepatocellular carcinoma. Standard treatment using PEG-IFN and ribavirin is not effective against some HCV genotypes, besides that it has high cost and severe side-effects. Therefore, new treatments have been sought. Caffeine has been found to have beneficial effect in several liver disorders, including the improvement of abnormal liver biochemistry, cirrhosis and hepatocellular carcinoma. Caffeine acts directly by delaying fibrosis, beyond improving the function of liver cellular pathways and interfering with pathways used by the HCV replication cycle. Although, the caffeine showed positive effects for liver disorders and a direct interaction with cell pathways used by HCV, there is no evidence of a direct correlation between caffeine and HCV replication cycle. Thus, the current study proposed to establish the direct relationship between caffeine and different steps of HCV replication cycle. To this study, it was used the subgenomic replicon SGR-JFH-FEO, the full-length replicons FL-J6/JFH-5′C19Rluc2AUbi and JFH-1; and Huh-7.5 cell line. The viral expression was evaluated by Luciferase, Western blotting, Indirect immunofluorescence and qPCR. The caffeine demonstrated to be able to inhibit viral replication on different stages of viral replication, demonstrating an IC50 value of 0.7263 mM and reaching on safe concentrations, HCVcc maximal replication inhibition around 79 %. Caffeine demonstrated also 30 % of inhibition on viral entry on host cells when tested in combination with infectious supernatant. Moreover, this inhibition increased two fold when particles were exposed to caffeine before introduction on cell culture, possibly, indicating an interaction between caffeine and viral proteins. On the other hand, there is no influence of caffeine on viral ... / Mestre
12

The hepatitis C virus and immune escape : relation between sequence variations and the in vitro and in vivo functionality of the non-structural 3/4A complex /

Söderholm, Jonas, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
13

Hepatitis C virus kinetics during antiviral treatment /

Carlsson, Tony, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
14

Avaliação de parâmetros da resposta imunológica na co-infecção pelo HIV-1 e vírus das hepatites C e G (HGV/GBV-C) / Evaluation of parameters of immune response in co-infection with HIV-1 virus and hepatitis C and G (HGV / GBV-C)

Baggio-Zappia, Giovana Lótici [UNIFESP] 24 June 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:49:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-24. Added 1 bitstream(s) on 2015-08-11T03:26:20Z : No. of bitstreams: 1 Publico-160.pdf: 1425439 bytes, checksum: 3673b94c19926da28dd48fd0518c8c86 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A infecção pelo GBV-C é freqüente em indivíduos saudáveis e pode permanecer por longos períodos sem a manifestação de sinais e sintomas clínicos. O GBV-C é um flavivírus composto por uma única fita de RNA de polaridade positiva, intimamente relacionado ao HCV. Inicialmente, o GBV-C foi associado à casos de hepatite fulminante de etiologia desconhecida. Estudos posteriores, no entanto, falharam em associar o GBV-C a qualquer doença humana conhecida e o vírus foi negligenciado por um longo período até que estudos sugeriram um efeito benéfico da co-infecção em pacientes HIV soropositivos. Os estudos envolvendo a co-infecção HIV-GBV-C apresentam resultados controversos enquanto trabalhos avaliando a tripla infecção HIV-HCV-GBV-C ainda são raros. Com o intuito de avaliar o efeito do GBV-C sobre pacientes HIV e HIV-HCV co-infectados crônicos, incluímos uma coorte de 159 pacientes HIV soropositivos triados a partir do CCDI-UNIFESP. Os pacientes foram testados para a presença de anticorpos anti-E2 e RNA do GBV-C. Dos 107 pacientes HIV, negativos para o HCV, 41 (38,3 por cento) apresentaram marcadores de infecção pelo GBV-C, dos quais 17 (15,8 por cento) eram virêmicos e 24 (22,4 por cento) positivos para anticorpos anti-E2. Dos 52 pacientes HIV-HCV co-infectados, 24 (46,1 por cento) apresentaram marcadores de infecção pelo GBV-C, dos quais 14 (26,9 por cento) apresentaram viremia e 10 (19,2 por cento) foram positivos para anticorpos anti-E2 do GBV-C. Foram coletados dados epidemiológicos e avaliados marcadores virológicos, imunológicos e de função hepática, além da produção de IFN-γ e IL-2 em células T CD4, T CD8 e Tγδ e da avaliação do marcador de ativação celular CD38 em células T CD4 e T CD8. Não foram observadas diferenças estatísticas nos níveis de CV do HIV e nem na contagem de linfócitos T CD4 e T CD8, de acordo com o perfil de infecção. A resposta imune, avaliada pela produção de citocinas IFN-γ e IL-2 e da expressão do marcador de ativação celular CD38 não diferiu entre os grupos avaliados. A análise univariada demonstrou aumento dos níveis de ALT, AST e GGT no grupo de pacientes HIV-HCV co-infectados e no grupo triplo infectado HIV-HCV- GBV-C. A análise multivariada revelou a influência do GBV-C sobre o aumento da ALT nos pacientes com tripla infecção. Os nossos dados demonstram que o GBV-C não exerce influência positiva sobre a infecção pelo HIV e pode causar sobrecarga hepática, como demonstrado pela elevação da ALT, em pacientes com tripla infecção. Dessa forma, esta interação deve ser vista com cautela até que se exclua completamente a possibilidade de patogenicidade do GBV-C nessa situação. / GBV-C co-infection is frequent in humans and could last for years without clinical symptoms. GBV-C is a flavivirus composed by a single positive RNA strain, closely related to HCV. Initially in its discovery GBV-C was associated with non-A-B hepatitis. However, subsequent studies failed to associate GBV-C with any known human disease and the virus became neglected until a series of studies associated the virus with prolonged survival in HIV infected recipients. Studies evaluating the co-infection presents conflicting results whereas triple HIV-HCV-GBV-C infection remains to be clarified. With the aim to evaluate the effect of GBV-C upon HIV and HIV-HCV co-infected patients, we included a cohort of 159 HIV-seropositive patients from CCDI-UNIFESP. The patients were tested for the presence of anti-E2 antibodies and GBV-C RNA. Of the 107 HIV seropositive patients negative to HCV infection, 41 (38,3%) were positive to GBV-C infection markers, of whom 17 (15,8%) were GBV-C viremic and 24 (22,4%) were positive to anti-E2 antibodies. Of the 52 HIV-HCV co-infected patients, 24 (46,1%) were positive to GBV-C infection markers, of whom 14 (26,9%) were viremic and 10 (19,2%) presented anti-E2 antibodies. Epidemiological data were collected; virological and immunological markers and also hepatic function were evaluated. Besides, IFN- and IL-2 production on CD4, T CD8 and T cells and CD38 activation marker on T CD4 and T CD8 cells were also evaluated. No significant differences on HIV viral load nor on T CD4 and T CD8 cell counts were observed, according to the infection profile. Immune response, evaluated by the IFN- and IL-2 production and by the CD38 expression did not differ among the groups studied. Univariate analysis demonstrated higher ALT, AST and GGT levels in the HIV-HCV co-infetced and HIVHCV- GBV-C triple infected patients. The multivariate analysis demonstrated that the GBV-C influences ALT levels on triple infected patients. Our results demonstrate that GBV-C does not exerts beneficial effects upon chronically HIV infected patients, unlike, it can cause hepatic overload, as demonstrated by the higher ALT levels in the HIV-HCV-GBV-C triple infected patients. In the light of these results, is reasonable to prudently consider this interaction until the possible pathological role of GBV-C on this situation is completely excluded. / FAPESP: 05/57611-5 / TEDE / BV UNIFESP: Teses e dissertações
15

Evolutionary history, cross-species transmission and host adaptation of human viruses and their primate homologues

Lyons, Sinead Mary Kathleen January 2014 (has links)
At present the origins of major human pathogens associated with hepatic disease are poorly understood. The absence of such information pertaining to the evolutionary history of hepatitis B virus (HBV) and hepatitis C virus (HCV) and its genetically related viruses impacts upon the development of vaccines and effective eradication strategies. Studies are currently limited by the absence of historical samples from which to date the emergence of human infections and therefore the evolution of human hepatic viruses relies on epidemiological studies and genetic analysis of contemporary virus populations worldwide. Approximately one third of the world’s population is infected with HBV, and despite the availability of a vaccine, the virus is attributed with over 1 million deaths per year through liver disease. HBV variants infecting humans show genetic and antigenic heterogeneity and are currently classified into 8 genotypes A-H with nucleotide divergence of between 9-13%. In addition to these variants, recombination has been detected between genotypes A and D, and B and C, which can generate novel variants. The past 10 years has seen the detection of HBV in chimpanzees, gorillas and other non-human primates (NHPs) at frequencies comparable to those observed in regions of endemic human HBV infection. Despite the genetic divergence between human and NHP HBV variants the detection of recombination between human genotype C and chimpanzee and gibbon variants suggests that HBV can share hosts in nature. The evolutionary process that may have given rise to the distinct species-specific variants of NHP HBV within overlapping geographical regions has not been reconciled, with evidence supporting both allopatric speciation and co-speciation. HCV a member of the Flaviviridae family currently infects approximately 3% of the world’s population and is one of the major causes of chronic liver disease, hepatocellular carcinoma and liver cirrhosis. Human pegivirus (HPgV) a member of the Pegivirus genus of the Flaviviridae family infects approximately 5% of the world’s population, although it is of unknown disease association. Very recently, several studies of wild rodent and bat populations have revealed much greater viral diversity of members of both Hepacivirus and Pegivirus genera. Homologues of HCV have been detected in a range of species including domestic dogs (canine hepacivirus [CHV]) and horses (non-primate hepaciviruses [NPHV]). Similarly, several new pegiviruses have been described in horses (equine pegivirus, [EPgV] and Theiler’s Disease Associated Virus [TDAV]), several species of rodents (rodent pegivirus [RPgV]), and further species of bats (bat pegivirus, [BPgV]). Despite the differences in pathogenicity between HCV and HPgV infections, they share similar genomic organisation and are capable of establishing persistent infections in humans. Studies into bat, horse and rodent homologs of HCV and HPgV have yet to determine disease associations, transmission routes and seroprevalence. Studies presented within this thesis broaden our understanding of the clinical presentations and host range of NPHV and EPgV. Screening to determine the level of active and past infection to both viruses provides novel insight into infection frequencies, host range, disease progression and examines the correlation between infections and the presence or absence of hepatic disease. Research examining HBV variants circulating in NHPs in Cameroon provides novel evidence for the occurrence of recombination and cross species transmission between NHP variants of HBV and examines the role these findings play in expanding our understanding of the evolution of HBV.
16

Avaliação de soroprevalência HCV/HIV em mulheres e de marcadores bioquímicos de toxicidade sistêmica em homens usuários de crack

Diemen, Lisia von January 2013 (has links)
Introdução: O consumo de crack tem sido alvo de grande preocupação em vista de sua expressiva expansão e dos problemas sociais e de saúde decorrentes. A cocaína na forma de crack difere das outras vias de uso principalmente pelo seu rápido início de ação, pouco tempo de efeito e alta concentração plasmática, levando a um maior impacto orgânico e a um elevado potencial de dependência. A deterioração física e cognitiva são aspectos centrais na gravidade do uso dessa droga. As taxas de infecção pelo HIV e HCV são elevadas nessa população, mas os fatores de risco associados ainda não estão claros na literatura, em particular no Brasil. Há uma busca por marcadores biológicos que possam auxiliar a avaliar o impacto físico e cerebral ocasionados pelo uso do crack. Achados recentes sugerem que as neurotrofinas cerebrais e marcadores de estresse oxidativo possam ser úteis nesse sentido. Objetivos: Avaliar a prevalência e fatores de risco associados à infecção por HIV e HCV em mulheres usuárias de crack e investigar se os níveis de BDNF, TBARS e PCC em usuários de crack, antes e após desintoxicação, diferem de controles e respectivos correlatos clínicos. Método: O artigo 1 utiliza um desenho transversal com uma amostra de conveniência de 76 mulheres com uso recente de crack. Foram coletados sangue para os testes de HIV/HCV, dados demográficos e instrumentos que avaliaram conhecimento sobre AIDS, consumo de drogas e comportamentos de risco para AIDS. No artigo 2 uma coorte com 49 usuários de crack homens foram recrutados da internação do Hospital Psiquiátrico São Pedro em Porto Alegre e 97 controles comunitários foram obtidos de um bairro pobre da cidade de Canoas (região metropolitana de Porto Alegre). O sangue para análise de BDNF (artigo 2), TBARS e PCC (resultados complementares) foi coletado no primeiro dia de internação e no dia da alta nos usuários de crack e no dia da entrevista nos controles. Nas duas amostras e nos controles os participantes tinham mais de 18 anos e realizaram teste de urina para cocaína. Resultados: No artigo 1, a prevalência de HIV entre as mulheres foi de 37,0% e de HCV de 27,7%, sendo 15,1% a prevalência de co-infecção. A análise ajustada identificou 4 anos ou menos de escolaridade como maior chance de infecção por HIV – RC 4,72 (1,49-14,99) e por HCV RC - 4,51 (1,18-17,27) e ter realizado 3 ou mais testes para HIV na vida - RC 4,26 (1,29-14,04) associado com contaminação por HIV. No artigo 2, os níveis de BDNF entre homens usuários de crack foram significativamente menores na admissão (28,6±11,0) quando comparados com os controles (39,5±10,6) e com o valor na alta hospitalar (35,6±12,3), mesmo após ajuste para as variáveis confundidoras. O valor do BDNF na alta foi um pouco menor nos usuários de crack, mas sem diferença significativa em relação aos controles. O aumento do BDNF teve associação significativa com número de dias de internação e inversa com anos de uso de crack e número de pedras de crack utilizadas no último mês. Os resultados complementares mostram que os valores médios de TBARS e PCC são semelhantes na internação e alta em relação aos controles. Contudo, o valor do TBARS na alta e a alteração durante a internação foram diretamente correlacionados com a gravidade do consumo de crack. Conclusões: Nós encontramos uma alta prevalência de contaminação por HIV e HCV entre mulheres usuárias de crack e o baixo nível educacional foi o fator de risco mais importante identificado. Em relação aos valores de BDNF em homens, foi possível identificar que este se encontra reduzido na vigência do uso de crack, com aumento na abstinência precoce, passando a ter níveis comparáveis aos controles. O aumento do BDNF e a diminuição do TBARS durante a abstinência precoce foram relacionados à menor gravidade de uso do crack. Esses achados sugerem que as variações de BDNF e TBARS após desintoxicação inicial possam ser marcadores da gravidade do uso de crack e de prognóstico, a serem investigados em futuros estudos. / Background: Crack cocaine has a been subject of great concern in view of its widespread use, as well as its increasing social and health problems. Crack cocaine differs from other administration routes primarily by its rapid onset of action, short effect and high plasma concentrations, leading to a higher organic impact and high potential for addiction. Physical and cognitive deterioration are key aspects of crack cocaine induced impairment. Rates of HIV and HCV are high in this population, but risk factors are still unclear in the literature, particularly in Brazil. There is search for biomarkers that may help identify the physical and brain injuries caused by its use. Recent findings suggest that brain neurotrophins and oxidative damage markers may be useful in this regard. Objectives: To ascertain the HIV/HCV serostatus and associated risk behaviors for infection of female crack users. To evaluated BDNF, TBARS and carbonyl levels among crack cocaine users during inpatient treatment, before and after drug withdrawal, vs. healthy controls. Clinical correlates with changes in biomarkers levels were also assessed. Method: Paper 1 is a cross-sectional study with a convenience sample of 76 female crack cocaine users. Subjects answered NIDA’s Risk Behavior Assessment and the AIDS Information Questionnaire. In addition, blood was collected from subjects for HIV/HCV tests. Blood samples for serum BDNF (paper 2), TBARS and PCC (complementary results) evaluations were collected in a cohort of 49 male crack users on the first and last days of hospitalization and in 97 healthy controls. In both samples and in the control group subjects were 18 years old or more and underwent urine tests for cocaine. Results: In paper 1, the overall prevalence of HIV was 37.0%; HCV seroprevalence was 27.7%; 15.1% of the sample was co-infected with HIV and HCV. Four years of schooling or fewer (OR 4.72 - CI 95% ((1.49-14.99)) was associated with HIV and HCV infection (OR 4.51 - CI 95% (1.18-17.27)) after multivariate logistic regression. In paper 2 BDNF levels among male crack users were significantly lower upon admission (28.6±11.0) when compared to controls (39.5±10.6) and discharge (35.6±12.3), even after adjustment for confounding variables. At discharge, BDNF levels between patients and controls were similar. Number of crack rocks used in the last 30 days and years of crack use were inversely correlated with the outcome. Complementary results show that levels of carbonyl and TBARS are similar at admission and discharge compared to controls. However, the TBARS levels at discharge and its variation rate during hospitalization were significantly correlated with the severity of crack cocaine use. Conclusions: We found a very high prevalence of HIV and HCV infection among female crack users, and low education was the most important risk factor associated with both infections. With regard to BDNF levels among men, it was reduced while using crack cocaine increased in early withdrawal reaching levels similar to control group at discharge. Rates of BDNF increase and TBARS decrease were correlated with severity of crack use. These findings suggest that the variation of BDNF and TBARS during early withdrawal may be a marker of severity of crack use.
17

Papel dos níveis séricos de vitamina D e das variantes genéticas envolvidas na sua rota metabólica na hepatite C crônica

Azevedo, Laura Alencastro de January 2017 (has links)
Introdução: Nos últimos anos têm-se demonstrado que a vitamina D desempenha um papel crucial em muitas doenças agudas e crônicas, não só afetando as condições ósseas, mas também aumentando o risco de fraturas, doenças auto-imunes e câncer. A influência da vitamina D nas doenças do fígado tem sido amplamente discutida já que esta sofre metabolismo hepático. Indivíduos com doenças hepáticas, e em especial com hepatite C crônica, apresentam maior prevalência de deficiência de vitamina D. Objetivos: Avaliar, em duas amostras distintas, a influência dos níveis séricos de vitamina D e/ou dos polimorfismos envolvidos na sua rota metabólica na progressão da doença hepática crônica causada pelo vírus C. Métodos: A primeira amostra consistiu de um estudo transversal com 132 pacientes com hepatite C crônica genótipo 1 do Hospital de Clínicas de Porto Alegre (HCPA). Foi avaliada a influência de níveis séricos de vitamina D e dos polimorfismos rs7041 e rs4588 do gene GC no grau de fibrose hepática (escore METAVIR). As genotipagens foram feitas com ensaio TaqMan e as análises estatísticas foram realizadas no programa SPSS v.20.0. A segunda amostra consistiu da análise de dados extraídos da plataforma dbGaP. Foram investigados 681 pacientes com hepatite C crônica da coorte americana HALT-C, acompanhados pelo período quatro anos. Avaliou-se a relação de 40 polimorfismos dos genes DHCR7, GC, CYP2R1, CYP24A1, CYP27B1, VDR, SMAD3 e TGFB1 nos seguintes desfechos: piora da fibrose hepática; descompensação hepática (escore Child Pugh-Turcotte>7, ascite, encefalopatia hepática, peritonite bacteriana espontânea e/ou sangramento de varizes gastroesofágicas); desenvolvimento de carcinoma hepatocelular e morte do fígado. Os polimorfismos que não se encontravam disponíveis no banco de dados foram imputados com o programa Mach-Admix 2.0.203 e as análises foram no programa Plink 1.07 e foi realizada correção de Bonferroni. Nesta amostra, resultados com P<0,05 foram considerados 2 como tendência à associação. Resultados: Na amostra do HCPA, níveis diminuídos de vitamina D, bem como a deficiência grave de vitamina D, foram mais frequentes entre pacientes com fibrose intermediária/avançada (METAVIR 3 e 4). Embora os polimorfismos rs7041 e rs4588 e seus haplótipos tenham apresentado relação com os níveis séricos de vitamina D, estes não apresentaram associação com a gravidade da fibrose hepática. Na segunda amostra estudada, onze polimorfismos tiveram tendência à associação (P<0,05) com os desfechos analisados: quatro SNPs no gene DHCR7 com descompensação hepática (rs4944957, rs12800438, rs3829251 e rs4945008); dois no gene GC com piora da fibrose e morte do fígado (rs7041 e rs222020); dois no gene CYP2R1 com ascite ou carcinoma hepatocelular (rs7116978 e rs1562902); dois no gene VDR com sangramento de varizes gastresofágicas e carcinoma hepatocelular (rs4516035 e rs2239186); e um no gene SMAD3 com piora da fibrose e encefalopatia (rs2118610). Apenas um polimorfismo, rs1800469no gene TGFB1, apresentou associação com descompensação hepática após correção de Bonferroni (P<0,05/40). Conclusões: Nossos resultados demonstraram que níveis séricos menores de vitamina D estão associados à progressão da fibrose hepática na hepatite C crônica genótipo 1. Além disso, os onze polimorfismos da rota da vitamina D que apresentaram tendência à associação estatística, indicam que variantes genéticas da rota metabólica da vitamina D possuem fraca ou nenhuma relação com a progressão da hepatite C crônica, merecendo análises futuras. Já o polimorfismo rs1800469, do gene TGFB1, demonstrou potencial utilidade para auxiliar na identificação de pacientes com maior chance de descompensação hepática. / Introduction: In the past years it has been demonstrated that vitamin D plays a crucial role in many acute and chronic diseases, not only affecting bone conditions but increasing the chance of fractures, autoimmune diseases and cancer. Vitamin D influence in liver disease is also widely discussed since it undergoes trough hepatic metabolism. Subjects with liver diseases, especially chronic hepatitis C, present higher rates of vitamin D deficiency. Objectives: Evaluate, in two different samples, the influence of vitamin D serum levels and/or polymorphisms of vitamin D metabolic pathway in liver disease progression in patients with chronic hepatitis C. Methods: The first sample consisted of a transversal study with 132 patients from Hospital de Clínicas de Porto Alegre (HCPA) with chronic hepatitis C genotype 1. We evaluated the influence of serum levels of vitamin D and rs7041 and rs4588 GC polymorphisms over liver fibrosis (METAVIR scoring). Genotyping was performed with TaqMan probes and statistical analyses were conducted using SPSS v.20.0. The second sample was extracted from HALT-C cohort available in dbGap plataform. It included 681 patients with chronic hepatitis C, followed for 4 years. Forty polymorphisms in DHCR7, GC, CYP2R1, CYP24A1, CYP27B1, VDR, SMAD3 and TGFB1 genes were analyzed with the following outcomes: worsening of fibrosis; hepatic decompensation (gastric/esophageal bleeding, CTP > 7, ascites, spontaneous bacterial peritonitis, and/or encephalopathy); development of hepatocellular carcinoma; and liver death. Polymorphisms not available in dbGaP data were imputed using Mach-Admix 2.0.203 software and analyses were performed in Plink v.1.07 and a Bonferroni’s correction was performed. Results with P<0.05 were considered as having tendency towards association. Results: In HCPA sample low serum vitamin D, as well as severe vitamin D deficiency, were more frequent among patients with intermediate/severe fibrosis (METAVIR 3 and 4). Although rs7041 and rs4588 4 polymorphisms and its haplotypes presented association with serum levels of vitamin D, they were not associated with severity of liver fibrosis. In sample two, eleven polymorphisms presented tendency towards association (P<0.05) with the studied outcomes: four SNPs in DHCR7 with hepatic decompensation (rs4944957, rs12800438, rs3829251 and rs4945008); two in GC with worsening of fibrosis and liver death (rs7041 and rs222020); two in CYP2R1 with ascites or hepatocellular carcinoma (rs7116978 and rs1562902); two in VDR with gastric/esophageal bleeding and hepatocellular carcinoma (rs4516035 and rs2239186); and one in SMAD3 with worsening of fibrosis and encephalopathy (rs2118610). Only one polymorphism, rs1800469 in TGFB1, showed statistical significance with hepatic decompensation after Bonferroni’s correction (P<0.05/40). Conclusions: Our results demonstrated that low serum vitamin D has association with fibrosis progression in chronic hepatitis C genotype 1. Also, the eleven polymorphisms with tendency towards association indicate that genetic variants in vitamin D pathway possess weak or none relation with progression of chronic hepatitis C, deserving future analyses. Finally, polymorphism rs1800469 in TGFB1 demonstrated potential utility to help identify patients with higher odds of hepatic decompesantion.
18

Design and synthesis of Hepatitis C Virus NS3 protease inhibitors /

Johansson, Anja, January 2003 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 4 uppsatser.
19

Studies of the hepatitis C virus envelope proteins : interaction with host cells and as targets for the humoral response /

Beyene, Aster, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
20

Modulation of the host cell signaling pathways and protein synthesis by hepatitis C virus nonstructural 5A protein /

He, Yupeng. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 207-251).

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