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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.
361

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.
362

Accelerated ageing, senescence and the natural history of chronic hepatitis B virus infection

Tachtatzis, Phaedra Maria January 2015 (has links)
Hepatitis B virus infection (HBV) is an important health problem worldwide, with a significant rate of chronic infection, which can lead to cirrhosis and hepatocellular carcinoma (HCC). Increased age is an important determinant of progression to cirrhosis and HCC, possibly because age is a crude measure of the duration of HBV infection. Increasing age is associated with changes in liver structure, blood flow and function and with reduced response to injury, impaired regeneration and increased mortality in acute liver disease. Age has been identified as a co‐factor in several chronic liver diseases including chronic hepatitis C infection (HCV). Available evidence suggests differential ageing of various intrahepatic cell types in different liver diseases and the ageing process may be more complex in the liver than originally thought. Telomeres are DNA structures located at the end of each chromosome, which protect the underlying coding DNA from breaks and fusions and shorten with increasing age. Both DNA damage and cell proliferation lead to progressive telomere shortening, which ultimately leads to cell cycle arrest and a state of replicative senescence. Persistent HCV and HBV infections lead to cell cycle arrest, providing a favourable environment for viral replication. Evidence suggests that progressive telomere shortening occurs with advancing stage of liver disease in HBV and specifically from cirrhosis through large cell dysplasia to small cell dysplasia and to HCC. Whether cell cycle arrest leads to a senescent‐like state or whether this is the result of oxidative stress is unknown. Unpublished data using cell cycle phase markers in chronic HBV infection reveal that hepatocytes, which support HBV replication, are arrested in G1, which is mediated by hepatocyte p21 expression. I hypothesise that: 1. In normal liver tissue, different cell types age at different rates and this is altered during disease; 2. Hepatocyte senescence plays a significant role in the natural course of chronic HBV infection and underlies HBV antigen expression. I developed and optimised large volume Q‐FISH methodology to measure telomere length and nuclear size in a variety of intrahepatic cell lineages. In normal liver tissue, cholangiocytes had longer telomeres compared with all other intrahepatic lineages over a wide age range. Hepatocytes did not show any age‐related telomere shortening, in contrast to Kupffer and hepatic stellate cells. In chronic HBV infection, all hepatocytes had shortened telomeres when compared to age and sex‐matched controls consistent with accelerated ageing. HBV replication was confined to those hepatocytes with longer telomeres, suggesting that HBV entry or replication is less efficient in older hepatocytes and compatible with the fall in serum HBV DNA and HBsAg titre seen with advancing age. There may be two populations of hepatocytes in chronic HBV infection; hepatocytes that are growth arrested with short telomeres not supporting HBV replication and biologically 'younger' hepatocytes with longer telomeres that do support HBV replication. The change in cellular HBV antigen localisation with disease progression is also explained by age related changes in HBV expression. Nuclear Hepatitis B core antigen expression (HBcAg), characteristic of the early immune tolerant phase of infection, was associated with the longest telomeres, while cytoplasmic HBcAg expression was associated with shorter telomeres. Furthermore, the total number of hepatocyte telomeres fell with increasing fibrosis stage. Hepatocyte nuclear size, a marker of senescence, increased as HBcAg expression shifted from nucleus to cytoplasm; and p21, another senescence marker, never co‐localised with HBcAg expression. These results suggest that the location and production of HBV antigens are related to increased functional hepatocyte age and the onset of cellular senescence.
363

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.
364

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.
365

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.
366

Prävalenz von chronischer Hepatitis B bei schwangeren Frauen in einem Krankenhaus der tertiären Versorgungsstufe in Tansania: Eine Querschnittsstudie mit Follow-Up / Prevalence of chronic hepatitis B among pregnant women in a tertiary care hospital in Tanzania: a cross-sectional study with follow-up

Geffert, Karin Ursula January 2021 (has links) (PDF)
Eine chronische Infektion mit dem Hepatitis B Virus (HBV) ist ein wichtiges, jedoch vernachlässigtes Problem der globalen Gesundheit. Weltweit sind ungefähr 257 Millionen Personen chronisch mit dem Virus infiziert. Eine Impfung gegen diese Erkrankung ist seit 1982 verfügbar. Impfprogramme haben dort, wo die Impfung ausreichend verfügbar ist, einen durchschlagenden Erfolg in der Reduktion von chronischer Hepatitis B gezeigt. Es gibt jedoch Teile der Welt, in denen die Impfung nicht zu einem ausreichenden Schutz führt, da die Infektion schon vor der Gabe der ersten Impfdosis geschieht oder die Impfung nicht oder nur unvollständig verabreicht wird. In Ländern mit einer hohen Prävalenz von Hepatitis B wird das Virus vor allem von Müttern auf Kinder übertragen. Kinder, die sich innerhalb ihres ersten Lebensjahres infizieren, haben hohes Risiko eine chronische Infektion zu entwickeln. Tansania, mit einer Prävalenz der chronischen Hepatitis B von 7,2% in der Allgemeinbevölkerung, gilt als Hochendemiegebiet der Erkrankung. Die Weltgesundheitsorganisation (WHO) nennt in ihrer globalen Strategie zur Elimination von viralen Hepatitiden die Prävention von Mutter-Kind-Übertragung als eine zentrale Aufgabe. Das beinhaltet unter anderem die Testung von schwangeren Frauen und die Impfung von Neugeborenen gegen HBV innerhalb von 24 Stunden nach der Geburt. Diese Maßnahmen sind jedoch in Tansania nicht implementiert. Zudem lagen zum Durchführungszeitraum der Studie nur wenige Daten zu der Prävalenz von HBV in schwangeren Frauen vor. Aus diesem Grund untersuchte die Studie die Prävalenz von Hepatitis B unter schwangeren Frauen in einem Krankenhaus der tertiären Versorgungsstufe in Mwanza, Tansania, sowie den sozio-ökonomischen Hintergrund und mögliche Risikofaktoren für eine Infektion seitens der Mütter. Ergänzend wurden verschiedene serologische und virologische Analysen des Blutes der Mütter und ihrer Kinder durchgeführt. / Chronic hepatitis B virus (HBV) infection is an important but neglected global health problem. Approximately 257 million people worldwide are chronically infected with the virus. Vaccination against this disease has been available since 1982 and vaccination programs have shown resounding success in reducing chronic hepatitis B where vaccination is sufficiently available. However, there are parts of the world where vaccination does not result in adequate protection because infection occurs before the first dose of vaccine is administered or because vaccination is not administered or is incomplete. In countries with a high prevalence of hepatitis B, the virus is transmitted primarily from mothers to their children. Children who become infected within their first year of life are at high risk of developing chronic infection. Tanzania, with a prevalence of chronic hepatitis B of 7.2% in the general population, is considered a high-endemic area for the disease. In its global strategy for the elimination of viral hepatitis, the World Health Organization (WHO) identifies prevention of mother-to-child transmission as a key task. This includes, among others, testing pregnant women and vaccinating newborns against HBV within 24 hours after birth. However, these measures have not been implemented in Tanzania. In addition, few data were available on the actual prevalence of HBV in pregnant women at the time the study was conducted. For this reason, the following study investigated the prevalence of hepatitis B among pregnant women in a tertiary care hospital in Mwanza, Tanzania, as well as the socioeconomic background and possible risk factors for infection on the part of the mothers. In addition, various serological and virological analyses of the blood of the mothers and their children were performed.
367

Hepatitis C Virus and the Lung: Implications for Therapy

Moorman, Jonathan, Saad, Mustafa, Kosseifi, Semaan, Krishnaswamy, Guha 01 January 2005 (has links)
Hepatitis C virus (HCV) infection is a chronic blood-borne disease that affects > 4,000,000 individuals in the United States. The majority of individuals with HVC infection acquire a chronic hepatitis that predisposes them to the complications of cirrhosis and hepatoma. Chronic HCV infection is, however, associated with multiple extrahepatic manifestations as well, including recently recognized effects on the lung. These include primary effects on lung function, as well as secondary effects in the settings of progressive liver disease and drug treatment for HCV. In this article, we discuss the emerging clinical data that support a role for HCV infection in lung disease, describe the multiple pulmonary manifestations of this viral infection, and outline the therapies available for specific pulmonary complications of chronic HCV infection.
368

Splenectomy Prolongs the Effects of Corticosteroids in Mouse Models of Autoimmune Hepatitis / 脾摘は自己免疫性肝炎モデルマウスにおけるコルチコステロイドの治療効果を延長する

Maruoka, Ryutaro 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18171号 / 医博第3891号 / 新制||医||1003(附属図書館) / 31029 / 京都大学大学院医学研究科医学専攻 / (主査)教授 三森 経世, 教授 生田 宏一, 教授 河本 宏 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
369

An Exploration of Hepatitis Polices and Prevalence in Prison: An Ecological Approach

Stives, Kristen Lynn 09 May 2015 (has links)
Hepatitis is an infectious disease that affects millions of people worldwide. The current project seeks to achieve two objectives: 1) To understand how hepatitis policies affect hepatitis prevalence in prison, and 2) To understand how hepatitis prevalence in prison affects the general population. Using a content analysis of correctional policies available through each state Department of Corrections (DOC) and secondary data from the 2010 Census, Centers for Disease Control and Prevention, and Corrections Compendium; hepatitis prevalence and policies are analyzed. The content analysis employed for this study revealed that some states have more comprehensive policies than others. However, all states may benefit from modifying their policies to meet recommendations constructed by the Federal Bureau of Prisons. Findings from descriptive statistics also suggest changes in HIV prevalence and policies positively affect hepatitis C prevalence. Future research should be dedicated to examining how personal interactions in prison also affect prevalence rates.
370

Virové hepatitidy: nové poznatky a nové možnosti léčby. / Viral hepatitis: novel insights and novel therapeutic interventions.

Davidovová, Eva January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Bc. Eva Davidovová Supervisor: prof. PharmDr. Petr Pávek, Ph.D. Title of diploma thesis: Viral hepatitis: novel insights and novel therapeutic interventions. Viral hepatitis is a well-known worldwide problem. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are characterized by the development of serious complications, especially with regard to the transition to the chronic stage of the disease, associated with the development of fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Interactions between viruses and host cells are quite complicated and not always fully understood. In general, the infection cycle of viruses is a multi-step process. A closer understanding of the entire life cycle of the virus is a major prerequisite for the invention of effective drugs. Viral hepatitis B and C have long been treated mainly with interferon alfa. Ribavirin was later added to HCV treatment and nucleoside / nucleotide analogs (NA) were introduced for HBV. Interferon was later pegylated to improve its properties. However, these drugs did not provide sufficient efficacy and were additionally associated with a number of side effects. It is precisely because of these disadvantages of the current...

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