• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 332
  • 233
  • 76
  • 31
  • 20
  • 14
  • 13
  • 10
  • 10
  • 6
  • 5
  • 5
  • 3
  • 3
  • 2
  • Tagged with
  • 854
  • 854
  • 352
  • 329
  • 122
  • 110
  • 90
  • 88
  • 80
  • 76
  • 66
  • 64
  • 59
  • 55
  • 53
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Influência do vírus da hepatite B na infecção crônica pelo vírus da hepatite C : perfil das séricas e histopatologia hepática /

Gryninger, Gabriela. January 2009 (has links)
Orientador: Jussara Marcondes Machado / Banca: Sueli Aparecida Calvi / Banca: Maria Cassia Jacintho Mendes Correa / Resumo: O vírus da hepatite C é uma das principais causas de doença hepática no mundo inteiro. O estudo histopatológico é de grande importância no prognóstico e indicação de tratamento. A coinfecção com o vírus da hepatite B oculta pode agravar a lesão hepática e diminuir a resposta ao tratamento. As citocinas IL-2, INF, TNF- induzem lesão hepática e fibrose. A IL-10 apresenta atividade antiinflamatória e o TGF- induz o desenvolvimento e depósito de matriz extracelular causando fibrose. Este estudo avaliou, em pacientes com HCC, a presença da hepatite B oculta, a dosagem das citocinas IL-2, INF, TNF , TGF e IL-10, correlacionando com o estágio de fibrose em pacientes tratados e não tratados com interferon, comparando também com indivíduos saudáveis. Foram estudados 55 pacientes com HCC crônica, atendidos na Faculdade de Medicina de Botucatu, excluindo-se pacientes imunossuprimidos e gestantes. O grupo controle foi constituído de 20 indivíduos doadores de sangue. O vírus da hepatite B oculto foi pesquisado por de PCR in house, segundo técnica de Kaneno, com limite de detecção menor que 100 cópias/ml. A dosagem de citocinas foi determinada por método de Elisa. A avaliação da fibrose hepática seguiu aquela proposta pela Sociedade Brasileira de Patologia. Os resultados mostraram predominância do gênero masculino, adulto jovem, 36,4% foram usuários de drogas endovenosas e 41,8% haviam sido hemotransfundidos. Nenhum paciente apresentou coinfecção pelo vírus da hepatite B oculto. Na biópsia hepática predominou fibrose leve ou ausência de fibrose (47,2%). As citocinas analisadas não discriminaram o grau de fibrose nos indivíduos com HCC crônica, mesmo quando separados em pacientes que foram submetidos ao tratamento e pacientes que não receberam o tratamento. Não houve também discriminação das citocinas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Hepatitis C virus is one of the major causes of hepatic diseases worldwide. Histopathological analyses play a leading role in determining disease outcome and treatment. Co-infection with occult Hepatitis B can aggravate liver injury and diminish treatment response. Cytokines such as IL-2, INF and TNF- induce liver injury and fibrosis. IL-10 has an antiinflamatory action and TGF- induces extracellular matrix development and deposition causing fibrosis. In this study, the presence of occult Hepatitis B and the expression of IL-2, INF, TNF , TGF and IL-10 were assessed in HCC patients and correlated with fibrosis stage in patients treated and non-treated with interferon, as well as healthy individuals. A total of 55 patients with chronic HCC seen at Botucatu Medical School were included. Immunosuppressed or pregnant patients were excluded. The control group consisted of 20 blood donors. The occult Hepatitis B virus was detected by in-house PCR according to the technique of Kaneno with a detection limit < 100 clones/ml. Cytokine levels were determined by the Elisa method. Hepatic fibrosis was assessed as proposed by the Brazilian Society of Pathology. The results showed a predominance of male young adults of whom 36.4% had used endovenous drugs and 41.8% had been hemotransfused. No patient showed occult Hepatitis B co-infection. Hepatic biopsy revealed that fibrosis was either absent or mild in most cases (47.2%). The cytokines under study did not correlate with fibrosis stage in individuals with chronic HCC no matter whether they had or not received treatment. In addition, no correlations with cytokine levels were observed when VHC patients were separated into groups of individuals treated and non-treated with interferon . However, cytokine expressions were significantly increased in all cases in comparison with the control group. / Mestre
82

Imunossensores à base de filmes nanoestruturados de fibroína da seda - peptídeo antigênico NS5A-1-vanadato de ítrio: európio para detecção de Hepatite C /

Lima, Lais Roncalho de. January 2014 (has links)
Orientador: Sidney José Lima Ribeiro / Co-orientador: Marli Leite de Moraes / Banca: Eduardo Maffud Cilli / Banca: Orlando Fatibello Filho / Resumo: Neste trabalho foram investigados a fibroína da seda (silk fibroin, SF) com o peptídeo antigênico da proteína NS5A-1 derivado do vírus da hepatite C (HCV) e nanopartículas de vanadato de ítrio dopadas com európio em filmes nanoestruturados. Dois foram os tópicos abordados: i) interação e organização estrutural do peptídeo com a fibroína. ii) imobilização do peptídeo, da fibroína e nanopartículas em filmes automontados (Layer-by-Layer, LbL), visando estudar a interação específica peptídeo antigênico-anticorpo e a produção de protótipos de imunossensores. As interações fibroína-peptídeo foram estudadas em solução e em filmes LbL pelas técnicas espectroscópicas de dicroísmo circular e luminescência. Os resultados indicaram que há uma mudança conformacional da fibroína em solução para a fibroína em filmes, de aleatória para folha-β, respectivamente, e que o filme de fibroína induz a estrutura secundária do peptídeo que não possui uma conformação bioativa em solução. O crescimento dos filmes LbL foi monitorado por espectroscopia UV-visível, e pôde-se observar um crescimento linear a cada deposição realizada. Além do estudo fundamental das interações a nível molecular, os sistemas foram utilizados para o desenvolvimento de protótipos de imunossensores. A interação peptídeo antigênico-anticorpo foi estudada por medidas de detecção eletroquímica, elétrica e óptica. Para a detecção eletroquímica realizou-se medidas de voltametria cíclica, indicando uma diminuição na corrente quando em presença dos anticorpos anti-HCV e testes em amostras reais soropositivas para o vírus, que indicaram uma maior densidade de elétrons nos voltamogramas referentes às amostras infectadas. A detecção elétrica foi analisada por espectroscopia de impedância elétrica, e observou-se que há um aumento no sinal da capacitância e das perdas dielétricas de acordo com o aumento da concentração... / Abstract: The present study investigated the silk fibroin (SF) with the antigenic peptide of the NS5A-1 protein of the hepatitis C virus (HCV) and nanoparticles of yttrium vanadate doped with europium immobilized on nanostructured films. Two main topics were explored: i) interaction and structural organization of the peptide with fibroin. ii) immobilization of the peptide together with fibroin and nanoparticles in LbL films (Layer- by- Layer), in order to study the specific interaction peptide antigen-antibody and production of prototype immunosensors. The fibroin-peptide interactions were studied in solution and in LbL films by spectroscopic techniques of circular dichroism and luminescence. The results indicate that there is a conformational change of fibroin in the fibroin solution in film, sheet to random coil-B, respectively, and that the fibroin film induces the secondary structure of the peptide does not possess a bioactive conformation in solution. The growth of the LbL films was monitored by UV-visible spectroscopy, and could observe a linear growth every deposit made. Besides the fundamental study of interactions at the molecular level, the systems were used for the development of prototype immunosensors. The peptide antigen-antibody interaction was studied by electrochemical, electrical and optical detection measures. For electrochemical detection, were made cyclic voltammetry measurements indicating a decrease in current when in the presence of anti-HCV antibodies, and were made tests on real samples seropositive for the virus, which indicated a higher density of electrons in voltammograms respect to infected samples. The electrical detection was analyzed by electrical impedance spectroscopy, and it was observed that there is an increase in the signal of capacitance and the dielectric losses in accordance with the increase in antibody concentration. This increase in signal is higher for films containing smaller number of bilayers and... / Mestre
83

Efeito da estimulação transcraniana por corrente contínua nos sintomas associados ao tratamento com interferon peguilado em portadores de hepatite C crônica

Brietzke, Aline Patrícia January 2013 (has links)
Introdução: O tratamento da hepatite C crônica com intereferon dura de 48 a 72 semanas, dependendo do genótipo. Os efeitos adversos mais prevalentes são dores pelo corpo, sintomas depressivos e piora na qualidade de vida. O tratamento torna o paciente incapacitado para suas tarefas diárias e atrapalha a adesão ao tratamento. Dessa forma, faz-se necessário buscar novas alternativas para minimizar os danos tornando o tratamento menos agressivo ao paciente e diminuindo os sintomas. Objetivo: Foram testadas duas hipóteses. A primeira foi explorar se a estimulação transcraniana por corrente continua (ETCC) seria mais eficaz em pacientes tratados com interferon peguilhado (PegINF) no tratamento da hepatite C crônica do que um placebo-sham para a redução dos sintomas dolorosos avaliados por meio dos níveis de dor e do limiar de dor a pressão. A segunda foi testar se os efeitos da ETCC nos sintomas relacionados ao uso de PegINF estariam relacionados ao processo de neuroplasticidade avaliado por meio dos níveis séricos de BDNF. Métodos: Foram recrutados 28 pacientes com hepatite C crônica, destros, com idades entre 40-74 anos, com escore de dor na escala numérica acima de 4 e com e limitações funcionais para realizar atividades de rotina devido à dor. Estes pacientes foram randomizados para um dos grupos de tratamento – placebo-sham (n=14) ou ETCC ativo (n=14). O tratamento consistiu em uma sessão diária de ETCC durante cinco dias consecutivos com a estimulação de 2mA aplicada na área do córtex motor primário(M1) do lado dominante. Os instrumentos de avaliação utilizados foram questionário para avaliar nível socioeconômico e dados demográficos, Escala Analógica Visual de dor (VAS), Escala do perfil de dor crônica (B-PCP:S) e níveis séricos de BDNF. Resultados: Comparando ETCC ativo com placebo-sham, ETCC ativa apresentou escores de dor significativamente mais baixos de VAS (P<0,003). A interação entre grupo e tratamento não foi significativa (P=0,07). A ETCC ativa resultou em redução da média de dor em 56% em comparação com o placebo-sham (P<0,001). Além disso, em comparação com placebo-sham, ETCC ativa resultou em melhora significativa no limiar de dor por pressão (P = 0,007) e no B-PCP: S (P <0,001), bem como reduziu o numero de doses analgésicas (P <0,03). O grupo da ETCC ativa também teve aumento significativo do BDNF no soro a partir da linha de base que foi de 37,48% (ETCC ativo) em comparação com 1,48% (diminuição do placebo-sham), esta diferença foi significativa (P <0,01). Conclusão: Concluímos que há grande potencial de utilização dessa técnica no tratamento de pacientes com hepatite c crônica, no que diz respeito ao alívio da dor, limiar de dor e diminuição dos níveis de BDNF. / Background: The treatment of chronic hepatitis C with intereferon lasts 48-72 weeks depending on the genotype. The most prevalent adverse effects are body pain, depressive symptoms and poor quality of life. The treatment makes the patient incapacitated for their daily tasks and interfere with treatment adherence. Thus, it is necessary to seek new alternatives to minimize the damage becoming less aggressive treatment to the patient and decreasing symptoms. Objective: Two hypotheses were tested . The first was to test whether transcranial direct current stimulation ( tDCS ) would be more effective in patients treated with interferon pegylated (PegINF) in the treatment of chronic hepatitis C than placebo-sham to reduce painful symptoms assessed by levels of pain and pressure pain threshold. The second was to test whether the effect of the tDCS related to use of PegINF symptoms would be related to the neuroplasticity process evaluated by means of BDNF serum. Methods: We recruited 28 patients with chronic hepatitis C, right-handed, aged 40-74 years, with a pain score on a scale above 4 and with functional limitations to perform routine activities due to pain. These patients were randomized to one of the treatment groups - placebo-sham (n = 14) or active tDCS (n=14). The treatment consisted of a daily session of 2mA tDCS for five consecutive days, applied in the primary motor cortex (M1) of the dominant hand area. The assessment instruments were used questionnaire to assess socioeconomic and demographic data, visual analogue scale for pain (VAS), scale profile of chronic pain (B-PCP:S) and serum BDNF levels. Results: Compared active tDCS with placebo-sham, active tDCS scores showed significantly lower pain VAS (P<0.003). The interaction between group and treatment was not significant (P =0.07). The active tDCS resulted in a reduction in average pain by 56% compared with the placebo -sham (P < 0.001). Moreover, active tDCS compared with placebo-sham, active tDCS resulted in significant improvement in the pain pressure threshold (P = 0.007) and the B -PCP:S (P<0.001) and reduced the number of analgesic doses (P < 0.03). The active tDCS group also had significantly increased BDNF in serum from the baseline that was 37.48 % (active tDCS) compared to 1.48% (reduced placebo-sham), this difference was significant (P < 0.01). Conclusion: We conclude that there is great potential for using this technique in the treatment of patients with chronic hepatitis C, with regard to pain relief, pain threshold and decreased levels of BDNF.
84

Efeito da estimulação transcraniana por corrente contínua nos sintomas associados ao tratamento com interferon peguilado em portadores de hepatite C crônica

Brietzke, Aline Patrícia January 2013 (has links)
Introdução: O tratamento da hepatite C crônica com intereferon dura de 48 a 72 semanas, dependendo do genótipo. Os efeitos adversos mais prevalentes são dores pelo corpo, sintomas depressivos e piora na qualidade de vida. O tratamento torna o paciente incapacitado para suas tarefas diárias e atrapalha a adesão ao tratamento. Dessa forma, faz-se necessário buscar novas alternativas para minimizar os danos tornando o tratamento menos agressivo ao paciente e diminuindo os sintomas. Objetivo: Foram testadas duas hipóteses. A primeira foi explorar se a estimulação transcraniana por corrente continua (ETCC) seria mais eficaz em pacientes tratados com interferon peguilhado (PegINF) no tratamento da hepatite C crônica do que um placebo-sham para a redução dos sintomas dolorosos avaliados por meio dos níveis de dor e do limiar de dor a pressão. A segunda foi testar se os efeitos da ETCC nos sintomas relacionados ao uso de PegINF estariam relacionados ao processo de neuroplasticidade avaliado por meio dos níveis séricos de BDNF. Métodos: Foram recrutados 28 pacientes com hepatite C crônica, destros, com idades entre 40-74 anos, com escore de dor na escala numérica acima de 4 e com e limitações funcionais para realizar atividades de rotina devido à dor. Estes pacientes foram randomizados para um dos grupos de tratamento – placebo-sham (n=14) ou ETCC ativo (n=14). O tratamento consistiu em uma sessão diária de ETCC durante cinco dias consecutivos com a estimulação de 2mA aplicada na área do córtex motor primário(M1) do lado dominante. Os instrumentos de avaliação utilizados foram questionário para avaliar nível socioeconômico e dados demográficos, Escala Analógica Visual de dor (VAS), Escala do perfil de dor crônica (B-PCP:S) e níveis séricos de BDNF. Resultados: Comparando ETCC ativo com placebo-sham, ETCC ativa apresentou escores de dor significativamente mais baixos de VAS (P<0,003). A interação entre grupo e tratamento não foi significativa (P=0,07). A ETCC ativa resultou em redução da média de dor em 56% em comparação com o placebo-sham (P<0,001). Além disso, em comparação com placebo-sham, ETCC ativa resultou em melhora significativa no limiar de dor por pressão (P = 0,007) e no B-PCP: S (P <0,001), bem como reduziu o numero de doses analgésicas (P <0,03). O grupo da ETCC ativa também teve aumento significativo do BDNF no soro a partir da linha de base que foi de 37,48% (ETCC ativo) em comparação com 1,48% (diminuição do placebo-sham), esta diferença foi significativa (P <0,01). Conclusão: Concluímos que há grande potencial de utilização dessa técnica no tratamento de pacientes com hepatite c crônica, no que diz respeito ao alívio da dor, limiar de dor e diminuição dos níveis de BDNF. / Background: The treatment of chronic hepatitis C with intereferon lasts 48-72 weeks depending on the genotype. The most prevalent adverse effects are body pain, depressive symptoms and poor quality of life. The treatment makes the patient incapacitated for their daily tasks and interfere with treatment adherence. Thus, it is necessary to seek new alternatives to minimize the damage becoming less aggressive treatment to the patient and decreasing symptoms. Objective: Two hypotheses were tested . The first was to test whether transcranial direct current stimulation ( tDCS ) would be more effective in patients treated with interferon pegylated (PegINF) in the treatment of chronic hepatitis C than placebo-sham to reduce painful symptoms assessed by levels of pain and pressure pain threshold. The second was to test whether the effect of the tDCS related to use of PegINF symptoms would be related to the neuroplasticity process evaluated by means of BDNF serum. Methods: We recruited 28 patients with chronic hepatitis C, right-handed, aged 40-74 years, with a pain score on a scale above 4 and with functional limitations to perform routine activities due to pain. These patients were randomized to one of the treatment groups - placebo-sham (n = 14) or active tDCS (n=14). The treatment consisted of a daily session of 2mA tDCS for five consecutive days, applied in the primary motor cortex (M1) of the dominant hand area. The assessment instruments were used questionnaire to assess socioeconomic and demographic data, visual analogue scale for pain (VAS), scale profile of chronic pain (B-PCP:S) and serum BDNF levels. Results: Compared active tDCS with placebo-sham, active tDCS scores showed significantly lower pain VAS (P<0.003). The interaction between group and treatment was not significant (P =0.07). The active tDCS resulted in a reduction in average pain by 56% compared with the placebo -sham (P < 0.001). Moreover, active tDCS compared with placebo-sham, active tDCS resulted in significant improvement in the pain pressure threshold (P = 0.007) and the B -PCP:S (P<0.001) and reduced the number of analgesic doses (P < 0.03). The active tDCS group also had significantly increased BDNF in serum from the baseline that was 37.48 % (active tDCS) compared to 1.48% (reduced placebo-sham), this difference was significant (P < 0.01). Conclusion: We conclude that there is great potential for using this technique in the treatment of patients with chronic hepatitis C, with regard to pain relief, pain threshold and decreased levels of BDNF.
85

L'EGCG et la delphinidine : deux nouvelles molécules naturelles inhibant l'entrée du virus de l'hépatite C / EGCG and delphinidin : two new natural inhibitors of hepatitis C virus entry

Calland, Noémie 23 November 2012 (has links)
L’hépatite C est un problème majeur de santé publique qui touche environ 160 millions de personnes dans le monde. L’agent étiologique responsable de cette maladie, le virus de l’hépatite C (HCV), est un petit virus enveloppé dont le génome est codé par un acide ribonucléique (ARN) simple brin de polarité positive. Actuellement, il n’existe aucun vaccin contre ce pathogène et les traitements utilisés sont insatisfaisants du fait de leur spécificité d’action limitée. Ainsi, afin d’établir une thérapie antivirale efficace évitant l’apparition et la sélection de mutants de résistance aux antiviraux, l’utilisation de plusieurs agents antiviraux ciblant directement la particule virale (direct acting antiviral agents ou DAAs) en combinaison est préconisée. C’est pourquoi la découverte de nouveaux DAAs à large spectre d’action ciblant diverses étapes du cycle viral infectieux est indispensable.Au cours de ma thèse, nous avons identifié un nouvel inhibiteur de l’entrée du HCV : l’épigallocatéchine-3-gallate (EGCG). Cette molécule, extraite du thé vert, inhibe l’infection des cellules par le HCV. Plus précisément, en utilisant des particules rétrovirales pseudotypées avec les glycoprotéines d’enveloppe E1 et E2 du HCV, nous avons démontré que cette catéchine naturelle, agit à une étape très précoce de l’entrée virale, indépendamment du génotype. De même, en nous servant du virus produit en culture cellulaire, nous avons montré que cette molécule agit directement sur la particule virale. Puis, par RT-PCR quantitative (quantitative real-time polymerase chain reaction), nous avons confirmé l’inhibition de la liaison du virus à la surface cellulaire, en présence d’EGCG. Par conséquent, nos travaux suggèrent que l’EGCG interagit avec la particule virale, probablement en se liant aux glycoprotéines d’enveloppe virales, bloquant ainsi une étape initiale d’attachement entre le virus et les facteurs cellulaires présents à la surface de l’hépatocyte. Puis, en inhibant la transmission libre du virus, à l’aide, soit d’agarose, soit d’anticorps neutralisants, nous avons démontré que l’EGCG inhibe la transmission du virus de cellule à cellule. Enfin, nous avons montré que l’EGCG élimine le virus présent dans le surnageant de culture cellulaire après quatre passages successifs sur des cellules naïves.La concentration d’EGCG nécessaire pour inhiber la moitié de l’infection virale (IC50) en culture cellulaire est 11 µM. Ainsi, afin d’identifier de nouvelles molécules présentant un mode d’action similaire à celui de l’EGCG et possédant une meilleure activité antivirale, nous avons sélectionnés différentes molécules naturelles et les avons testés pour leur potentiel effet anti-HCV. C’est ainsi que le chlorure de delphinidine, une anthocyanidine, a également été identifié en tant que nouvelle molécule inhibitrice de l’entrée du HCV. De même que l’EGCG, le chlorure de delphinidine cible directement la particule virale à une étape précoce de l’entrée, indépendamment du génotype, probablement en inhibant l’attachement du virus à la surface cellulaire et sans affecter ni l’étape de réplication, ni l’étape d’assemblage/maturation. De plus, le chlorure de delphinidine présente une activité anti-HCV améliorée avec une IC50 de 3 µM.Finalement, au cours de cette thèse, nous avons identifié deux nouvelles molécules naturelles inhibant l’étape d’entrée virale du HCV. Ces molécules pourraient être utilisées comme nouveau traitement en combinaison avec d’autres DAAs et pourraient également servir d’outil afin d’étudier les mécanismes d’entrée du HCV dans l’hépatocyte. / Hepatitis C is a major global health burden with 160 million infected individuals worldwide. This long-term disease, caused by a small positive-strand ribonucleic acid (RNA) enveloped virus, namely hepatitis C virus (HCV) evolves slowly. Nowadays, no vaccine is available and current treatments are unsatisfactory due to their restricted spectrum of action. For this reason, it is suggested that the combination of several drugs will prevent viral resistance and might conduct to an efficient antiviral therapy. Thus, the discovery of new direct acting antiviral agents (DAAs), with a broad spectrum of action, targeting different steps of the virus life cycle is still needed. Here, we identified (-)-epigallocatechin-3-gallate (EGCG) as a new inhibitor of HCV entry. Epigallocatechin-3-gallate, extracted from green tea, inhibits HCV infection. More precisely, this natural catechin molecule acts at a very early step of entry regardless of the genotype as illustrated with HCV pseudoparticles expressing HCV envelope glycoproteins E1 and E2 assays and cell-cultured HCV assays. Moreover, this molecule inhibits the docking of the virus to the cell surface as showed by the quantification of bound viruses during the attachment step using quantitative real-time polymerase chain reaction. Furthermore, EGCG inhibits viral cell-to-cell transmission as demonstrated by inhibiting cell-free transmission using agarose or neutralizing antibodies assays. Finally, EGCG clears HCV from cell culture supernatants after four passages.The half maximal inhibitory concentration (IC50) of EGCG in cell culture is approximately 11 µM. In order to identify new molecules exhibiting an enhanced anti-HCV activity and displaying similarities from EGCG scaffold, a series of natural compounds were selected and were tested for their anti-HCV activities. Thus, the anthocyanidin delphinidin chloride was identified as another inhibitor of HCV entry. Like EGCG, delphinidin chloride acts directly on the virus at a very early step of entry, regardless of the genotype, probably by inhibiting the docking of the virus to the cell surface without affecting replication or viral assembly/secretion. Finally, with an IC50 of 3 µM, delphinidin chloride displays a more potent anti-HCV activity.Together, these data indicate that EGCG and delphinidin chloride are new interesting anti-HCV molecules that inhibit entry and might be used as a new treatment in combination with other DAAs. Furthermore, these two inhibitors might be novel tools to further dissect the mechanisms of HCV entry into the hepatocyte.
86

Comparing the Efficacy of Direct Acting Antiviral Agents for the Treatment of Hepatitis C Virus Genotype 1

Ali, Rahma, Trinh, Sylvia, Turley, Jared, Malone, Dan, Honkonen, Marcella January 2016 (has links)
Class of 2016 Abstract / Objectives: To compare the efficacy of direct acting antiviral agents for the treatment of hepatitis C virus genotype 1. Our primary null hypothesis is there will be no significant difference in efficacy among the treatment regimens for hepatitis C virus, genotype 1. Methods: This meta-analysis study will use published literature identified from Embase and PubMed for phase II or III clinical trials evaluating direct acting antiviral drug regimens to treat adults with hepatitis C virus (HCV) genotype 1 infection. The primary outcome of interest is SVR at 12 weeks after treatment initiation. Data will be analyzed both descriptively as well as using Bayesian mixed treatment comparison methods. After extracting the outcome data from individual studies, the data will be analyzed using Winbugs version 1.4.3. Moreover, a random effects model and indirect/mix-treatment comparison will be used during the analysis. The random effects model accounts for both between-study and within-study variance, and is exempted from normality assumption, possessing a wider credible interval. All pair-wise odds ratios will be generated and treatment regimens will be ranked based on the likelihood of achieving SVR. Results: Overall, combinations containing sofosbuvir and ledipasvir were significantly better than all other treatments except for simeprevir (OR 0.52, 95% CI 0.28-1.00). On the other hand, daclatasvir containing regimens were non-inferior only to simeprevir (OR 0.69, 95% CI 0.35-1.31) and grazoprevir (OR 0.66, 95% CI 0.41-1.04) while being inferior to other treatments. Sofosbuvir with ledipasvir was ranked highest in terms of obtaining a sustained viral response, followed by ABT-450, grazoprevir, simeprevir, and daclatasvir respectively. In previously treated patients, sofosbuvir with ledipasvir again demonstrated the best efficacy with only grazoprevir and ABT-450 being non-inferior (OR 0.64, 95% CI 0.3368-1.212 and OR 0.73 95% CI 0.29-1.88 respectively). Sofosbuvir with ledipasvir was followed by grazoprevir, ABT-450, simeprevir, and daclatasvir containing regimens respectively. Finally, in treatment naïve patients, simeprevir containing regimens were non-inferior to all other treatment groups, including sofosbuvir regimens (OR 1.24, 95% CI 0.28-9.93). With the exception of simeprevir, sofosbuvir with ledipasvir demonstrated superiority over all treatments. Simeprevir regimens and sofosbuvir with ledipasvir regimens were followed by ABT-450. In treatment naive patients daclatasvir was found to be non-inferior to grazoprevir (OR 1.26, 95% CI 0.75-2.10). Treatment naive patients were the only group we analyzed in which daclatasvir was not the least effective regimen, with grazoprevir claiming the last position. Conclusions: Our results reject our null hypothesis that there will be no difference between different treatment regimens in HCV genotype 1 patients. Generally, the combination of sofosbuvir and ledipasvir appears to be the most effective, while daclatasvir appears to be the least.
87

Knowledge and Awareness of Hepatitis C Virus Among Second Year Pharmacy Students

Holt, Justin, Kocol, Samuel January 2005 (has links)
Class of 2005 Abstract / Objectives: To determine the change in knowledge regarding the prevalence, risk factors, transmission, and treatment of hepatitis C infections before and after an educational presentation to second year pharmacy students. Methods: Two questionnaires were administered to the study subjects. The pre-test was administered two weeks prior to the educational presentation and the post-test was administered immediately following the presentation. Students were required to attend the lecture, but participation in the pre- and post-tests was voluntary. The questionnaires addressed issues regarding general hepatitis C virus information as well as opinion questions surrounding the subject’s feelings about themselves and the disease state. Results: The mean number of correct responses on the post-test was significantly higher than the mean number of correct responses on the pre-test (p < 0.001). There was no statistically significant difference between males and females when comparing mean pre-test, post- test, and change between pre- and post-test scores. The data found no association between a student’s perceived risk level for developing hepatitis C and their knowledge about the hepatitis C virus, whether they had received prior hepatitis C testing, or the mean number of correct responses on either the pre-test or post-test. Implications: An educational presentation on hepatitis C is an effective tool to increase the knowledge of pharmacy students concerning the hepatitis C virus and its risks, prevalence, and treatment options.
88

Development of Biomolecular Tools for Studying Host-Virus Interactions of the Hepatitis C Virus

Nasheri Ardekan, Neda January 2015 (has links)
Hepatitis C virus (HCV) is a growing health concern in Canada and around the world, as it currently infects 3% of the global population. While there is no vaccine available against this virus, novel and effective treatment regimens have improved prospects for the cure of HCV. Complications caused by HCV can lead to severe liver disease and even death. The limited viral proteome forces HCV to rely heavily on various host factors for its replication. Additionally HCV modulates the host physiology to facilitate its pathogenesis; consequently, the in dept study of essential host-virus interactions expands our understandingof how the virus and related species commandere host cell machinery. This understanding can help create new therapeutic strategies, which may have applications towards HCV and other related RNA viruses. While numerous studies have demonstrated that HCV modulates the abundance of various host proteins, the systematic study of the virus’s effect on the enzymatic activity has been relatively unexplored. For this reason, activity-based protein profiling (ABPP) was applied to study the changes in the activity of host enzymes during HCV replication. ABPP is a functional proteomics technique that employs active site-directed probe (ABP) to report on the activity of enzymes within complex proteomes, such as living cells. Herein, directed and non-directed ABPs were employed for specific as well as global profiling of the alterations in the activity of cellular enzymes during HCV replication. As a result, essential host enzymes that are differentially active during HCV infection were identified. Furthermore, I have developed a quantitative ABPP method for relative quantification of the cellular enzymes activity during HCV infection. These results contribute to the discovery of disease-associated biomarkers, with diagnostic significance, and aid in the identification of potential targets for therapeutic interventions. In addition to developing protein-based tools to study host-virus interactions, I employed a novel technique to investigate the interactions of micro-RNA 122 (miR-122), an essential HCV host factor, with the viral RNA genome. This in vitro screening approach, interrogates the folding of HCV RNA using viral RNA-coated magnetic bead (VRB) to determine target site accessibility for RNA silencing. This method predicts the relative affinity of small RNAs towards HCV genomic RNA that are not easily predicted by informatic means, and led to discovery of potent miR-122 interaction site within the large, highly-structured HCV RNA genome. For that reason, VRB assay may represent an attractive tool for the examination of target site accessibility for RNA silencing.
89

Generalized Impairment of CD8+ T-cells in HCV Mono- and HIV-HCV Co-infection

Burke, Stephanie January 2015 (has links)
Chronic hepatitis C virus (HCV) infection has global effects on the immune system. CD8+ T-cells, responsible for viral clearance and control, are dysfunctional for as yet unknown reasons. It is hypothesized that IL-7 signaling pathway deficiencies contribute to this impairment. Blood-derived CD8+ T-cells in chronic HCV mono- and HIV-HCV co-infection had lower IL-7-induced activation of STAT5 and production of Bcl-2, and lower proliferation in co-infection, compared to controls. Lower Bcl-2 production was also associated with increased fibrosis. These changes were independent of the IL-7 receptor α expression and suppressor of cytokine signaling 1 or 3 expression. Intrahepatic CD8+ T-cells in HCV-infection did not activate STAT5 above basal levels with cytokine stimulation and had lower Bcl-2 expression than blood-derived cells. In conclusion, bulk CD8+ T-cells were impaired in response to IL-7 and the IL-7 signaling pathway may be one mechanism by which CD8+ T-cells are impaired in chronic HCV infection.
90

Značaj primene definicije slučaja za unapređenje epidemiološkog nadzora nad hepatitisima B i C / The importance of introducing case definitions for improving epidemiological surveillance of hepatitis B and C

Dakić Zoran 02 February 2017 (has links)
<p>Adekvatni nadzor nad zaraznim bolestima predstavlja aktuelni izazov ne samo kod nas već i u razvijenim zemljama. Savremeni epidemiolo&scaron;ki nadzor nad zaraznim bolestima zasniva se na odgovarajućim definicijama slučaja. Njihova osnovna funkcija je olak&scaron;avanje prepoznavanja određenih bolesti i njihovo registrovanje na jednoobrazan način. Definisanje slučajeva zaraznih bolesti nije jednostavno, jer uključuje kliničke, epidemiolo&scaron;ke i laboratorijske parametre, uz istovremeno očekivanje visoke senzitivnosti i specifičnosti. Ciljevi istraživanja su bili da se utvrdi primenljivost definicija slučaja hepatitisa B i C na Klinici za infektivne bolesti Kliničkog centra Vojvodine, te da se utvrdi senzitivnost i specifičnost primenjenih definicija slučaja hepatitisa B i C. Uz postojeći dijagnostički algoritam Klinike za infektivne bolesti Kliničkog centra Vojvodine, uvedena su tri seta definicija hepatitisa B i C: Evropskog centra za prevenciju i kontrolu bolesti (ECDC) iz 2008. i 2012.godine kao i američkih Centara za kontrolu bolesti (CDC) iz 2012. godine. Istraživanje je sprovedeno na Klinici za infektivne bolesti Kliničkog centra Vojvodine i tokom 12 meseci, u skladu sa predloženim definicijama slučaja, identifikovano je 150 ispitanika obolelih od hepatitisa B i C. Utvrđene su sledeće činjenice: preporučene definicije slučaja su primenljive u Republici Srbiji za laboratorijske i kliničke kriterijume, dok uključivanje epidemiolo&scaron;ke povezanosti u definicije slučaja ima malo praktičnog značaja za prijavljivanje hepatitisa; definicije slučaja koje uključuju i obavezno prisustvo kliničkih kriterijuma (najče&scaron;će definicije verovatnog slučaja) imaju nisku senzitivnost, a visoku specifičnost, kao posledica prisustva infekcije i u odsustvu bilo kakvih kliničkih manifestacija; definicije slučaja koje se zasnivaju samo na laboratorijskim kriterijumima imaju maksimalnu senzitivnost i specifičnost.</p> / <p>Adequate surveillance of communicable diseases is the actual challenge, not only in our country but also in developed countries. Modern epidemiological surveillance of communicable diseases is based on the appropriate case definitions. Their main purpose of them is to facilitate the recognition of certain diseases and their registration in a uniform manner. Case definition of communicable diseases is not easy, because it involves clinical, epidemiological and laboratory parameters, along with the expectated high sensitivity and specificity.The objectives of the study were to determine the applicability of the casedefinitions for hepatitis B and C in the Clinic for Infectious Diseases of the Clinical Center of Vojvodina and to determine the sensitivity and specificity of the applied definition of cases of hepatitis B and C. In addition to existing diagnostic algorithm of the Clinic for Infectious Diseases, three sets of hepatitis B and C case definitions were introduced: the European Centre for Disease Prevention and Control in 2008 and 2012 as well as the US Centers for Disease Control in 2012. The study was conducted at the Clinic for Infectious Diseases Clinical Center of Vojvodina over 12 months, and in accordance with the proposed case definitions, 150 patients suffering from hepatitis B and C were identified. We found following facts: recommended case definitions are applicable in the Republic of Serbia for laboratory and clinical criteria, while the inclusion of epidemiological connection between the case definition has little practical significance for reporting hepatitis; case definitions that include the obligatory presence of clinical criteria (most common definition of probable cases) have low sensitivity and high specificity, as a result of the presence of infection in the absence of any clinical manifestations; case definitions that are based solely on laboratory criteria showed maximum sensitivity and specificity.</p>

Page generated in 0.0632 seconds