Abstract Cytochrome P450 2A6 (CYP2A6) is involved in the 7-hydroxylation of coumarin, C-oxidation of nicotine, and the metabolism of tobacco specific nitrosamines. Initially in 1995 Fernandez-Salguero et al. reported a genotyping method for three alleles: CYP2A6*1 (wild-type), CYP2A6*2 (variant 1), and CYP2A6*3 (variant 2). Later studies presented in this thesis indicated that the original genotyping method produces erroneous results for the CYP2A6*3 allele due to unspecific PCR conditions and previously unknown CYP2A6*1B allele. Furthermore, the CYP2A6*2 allele genotyping caused erroneous genotypes (CYP2A6*2/*2 was misclassified as CYP2A6*1/*2). In this work, new PCR based genotyping methods were developed for CYP2A6*2 and for several new alleles (CYP2A6*1B, CYP2A6*4A/*4D and CYP2A6*5). In population-based studies, the deletion alleles (pooled as CYP2A6*4) turned out to be more prevalent among Asians (15.1%) than Caucasians (0.5%). The frequencies of the other inactive alleles varied within 0–3% in both populations. Asians totally lacked the CYP2A6*2 allele, whereas Caucasians lacked the CYP2A6*5 allele. The frequencies of two wild-type alleles, CYP2A6*1A and CYP2A6*1B alleles were 66.5% and 30.0% in Caucasians, and 43.2% and 40.6% in Asians, respectively. Correlation studies between the phenotype, as tested by the administration of coumarin, and the genotype demonstrated that individuals with the CYP2A6*2/*2 genotype were totally defective, while CYP2A6*1/*2 subjects exhibited intermediate and CYP2A6*1/*1 subjects full capablility of producing 7-hydroxycoumarin. Upon phenotyping with nicotine, individuals with the CYP2A6*1/*2 or CYP2A6*1/*4 genotype were shown to have a lower enzyme activity (one fourth of the normal activity), compared to those with the CYP2A6*1/*1 genotype. Defective CYP2A6 activity has been hypothesised to reduce the risk of environmentally (especially tobacco smoke) induced diseases either by decreasing production of genotoxic metabolites or by preventing addiction to tobacco smoking. However, in our case-control studies on Spanish patients with liver cirrhosis (n = 83) and liver cancer (n = 90) and their controls (n = 237) no significant association between the CYP2A6 genotypes and disease proneness was found. The odds ratio (OR) for developing liver cancer was was 1.4 (95% confidence interval [CI] 0.5–3.7) for genotypes containing at least one CYP2A6*2 allele. For liver cancer the respective OR was 1.3 (95% CI 0.4–4.5). Similarly, no statistically association between CYP2A6 alleles and the risk of lung cancer was observed in our Finnish study population cinsisting of 177 cases and 1089 controls; the OR for combined CYP2A6 variant allele containing genotypes (CYP2A6*1/*2 and CYP2A6*1/*4) was 1.19 (95% CI 0.56–2.45). Our studies therefore do not indicate any major modifying role for the CYP2A6 genotypes in individual susceptibility to environmentally induced diseases.

Background & Aims: Vasoactive agents with endoscopic therapy are used to treat acute variceal bleeding (AVB). There are two main groups of vasoactive agents: terlipressin and vasopressin (T-V), and octreotide and somatostatin (O-S). However, the benefit/harm balance is unclear. Our aim was to assess the efficacy and safety of T-V versus O-S for the management of AVB. Methods: We performed a systematic search for randomized controlled trials (RCTs) in PubMed, Scopus, and CENTRAL. Our main outcomes were mortality and adverse events. Secondary outcomes were bleeding control, rebleeding, blood transfusion, hospital stay. We evaluated the certainty of evidence using GRADE methodology. Results: We included 21 RCTs. The risk of mortality (RR: 1.01; 95%CI: 0.83-1.22), bleeding control (RR: 0.96; 95%CI: 0.91-1.02; I2=53%), early rebleeding (RR: 0.91; 95%CI: 0.66-1.24: I2=0%), late rebleeding (RR: 0.94; 95 CI: 0.56-1.60; I2=0%), blood transfusion (MD: 0.04; 95%CI:-0.31-0.39; I2=68%) and hospital stay (MD:-1.06; 95%CI:-2.80-0.69; I2=0%) were similar between T-V and O-S groups. Only 15 studies reported adverse events, which were significantly higher in the T-V compared to the O-S group (RR 2.39; 95%CI: 1.58-3.63; I2=57%). The certainty of evidence was moderate for the main outcomes, and low or very low for others. Conclusions: In cirrhotic patients with AVB, those treated with T-V had similar mortality risk compared to O-S. However, the use of T-V showed an increased risk of adverse events compared to O-S. / Revisión por pares

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Wong, Yee Man Melody. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 148-174). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgements --- p.iv / Abbreviations --- p.v / Review of the literature --- p.1 / Overview of liver fibrosis --- p.2 / Pathophysiology of liver fibrosis --- p.3 / Histological classification of liver fibrosis --- p.4 / Gold standard for fibrosis assessment - Liver biopsy --- p.6 / Biomarker in blood - non-invasive method for assessing diseases --- p.7 / Significance of non-invasive markers of liver fibrosis --- p.9 / Biomarkers of liver fibrosis --- p.10 / Direct markers --- p.10 / Indirect markers --- p.11 / Proteomics / Why proteomics? --- p.16 / Clinical values of proteomics in biomarker discovery --- p.17 / Challenges in proteomics --- p.18 / Current proteomics technologies in biomarker discovery --- p.21 / Gel based --- p.21 / Gel free approach - MS based --- p.23 / Quantitative proteomics --- p.29 / Application of proteomics to discovery of biomarkers for diagnosis of liver fibrosis --- p.33 / Rationale and Objectives of the Project --- p.35 / Chapter Section 1 --- Method development of magnetic beads-based proteomic profiling for quantitative proteomic profiling and micro- purification in parallel --- p.36 / Chapter 1.1 --- Introduction --- p.36 / Chapter 1.2 --- Materials and methods --- p.38 / Chapter 1.3 --- Results / Chapter 1.3.1 --- Serum proteome profiles obtained with different types of chromatographic magnetic beads --- p.46 / Chapter 1.3.2 --- Performance of PCS 4000 ProteinChip reader --- p.49 / Chapter 1.3.3 --- Reproducibility of magnetic beads-based serum proteomic profiling --- p.54 / Chapter 1.3.4 --- Gel electrophoresis of the eluted proteins --- p.58 / Chapter 1.3.5 --- Identification of the protein peaks --- p.58 / Chapter 1.4 --- Discussion --- p.60 / Chapter 1.5 --- Conclusion --- p.64 / Chapter Section 2 --- Development of a proteome-based fingerprinting model for detecting liver fibrosis in patients with chronic hepatitis B infection --- p.65 / Chapter 2.1 --- Introduction --- p.65 / Chapter 2.2 --- Materials and methods --- p.68 / Chapter 2.3 --- Results / Chapter 2.3.1 --- Patients characteristics --- p.75 / Chapter 2.3.2 --- Correlation between biochemical/serological markers and the degrees of liver fibrosis --- p.81 / Chapter 2.3.3 --- Serum proteomic profiling by linear MALDI-TOF MS --- p.81 / Chapter 2.3.4 --- Correlation of proteomic features with Ishak score --- p.81 / Chapter 2.3.5 --- Correlation of significant proteomic features with serological markers --- p.89 / Chapter 2.3.6 --- Construction of diagnostic model in detecting liver fibrosis and cirrhosis --- p.91 / Chapter 2.3.7 --- Cross-validation of the diagnostic model using pre- treatment samples in detecting liver fibrosis and cirrhosis --- p.91 / Chapter 2.3.8 --- Independent validation of the diagnostic model using post-treatment samples in detecting liver fibrosis and cirrhosis --- p.95 / Chapter 2.3.9 --- Comparison against other non-invasive models in detecting liver fibrosis and cirrhosis --- p.98 / Chapter 2.4 --- Discussion --- p.103 / Chapter 2.5 --- Conclusion --- p.112 / Chapter Section 3 --- Identification of proteomic features to form diagnostic fingerprint for the detection of liver fibrosis in patients with chronic hepatitis B infection --- p.113 / Chapter 3.1 --- Introduction --- p.113 / Chapter 3.2 --- Materials and methods --- p.115 / Chapter 3.3 --- Results --- p.121 / Chapter 3.3.1 --- Protein identification of the protein marker in the diagnostic model --- p.121 / Chapter 3.3.2 --- Immunodepletion of apolipoprotein C-III --- p.125 / Chapter 3.3.3 --- Serum levels of apolipoprotins and their association with liver fibrosis --- p.127 / Chapter 3.4 --- Discussion --- p.130 / Chapter 3.5 --- Conclusion --- p.139 / General discussion --- p.141 / Reference --- p.148 / Original Data --- p.175

Leung, Kin Chung. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 148-164). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Diss. (sammanfattning) Göteborg : Göteborgs universtiet, 2008. / Härtill 4 uppsatser.

abstract / Medicine / Master / Master of Philosophy

Orientador: Benedito Barravieira / Coorientador: Lucilene Delazani dos Santos / Banca: Carlos Antônio Caramori / Banca: Alexandre Leite Rodrigues de Oliveira / Resumo: INTRODUÇÃO: A cirrose é o estágio final da doença hepática. Causada principalmente pelas hepatites virais e ingestão de álcool, o único tratamento específico atual é o transplante O projeto Global Burden of Disease (GBD) publicou recentemente na BMC Medicine uma nova avaliação da mortalidade pela cirrose. Vários métodos e fontes de dados levaram a estimativa global de pouco mais de um milhão de mortes em 2010, cerca de 2% de todas as mortes. Nos últimos anos, as pesquisas biotecnológicas favoreceram a descoberta da terapia alternativa para cirrose usando células tronco. Estas geraram grande expectativa na regeneração tecidual e sua aplicação no tratamento. Um dos grandes desafios enfrentados foi sua reduzida fixação das células no fígado, com dispersão para todo organismo e sem a efetividade esperada. As metodologias ainda não encontraram uma maneira eficaz de impedir que estas células difundam para os outros órgãos diminuindo sua eficácia pretendida. OBJETIVO: Avaliar o selante de fibrina derivado da peçonha de serpente (SFDPS) como arcabouço para células tronco mesenquimais (CTMs) em fígados cirróticos. MÉTODOS: O modelo de cirrose experimental em ratos foi induzido pela tioacetamida (C2H5NS), aplicada duas vezes por semana por via intraperitoneal (i.v.) na dose de 200mg/kg. A coleta de sangue foi realizada uma vez por mês para as analises bioquímicas. O isolamento das células tronco foi realizado de acordo com Gasparotto et al., 2014. A marcação para citometria foi realizada em segunda passagem com os marcadores RT1 AW2 FITC, CLASS RT1 PE, CD11b, CD44, CD90, CD34, CD105, CD73, CD45, ICAM. A biomarcação da serinoprotease, um dos componentes do selante, foi realizada com o kit Alexa Fluor 488 Protein Labeling Kit (A30006v). A cirurgia foi realizada sob anestesia inalatória com isoflurano; os animais foram selecionados aleatoriamente em três grupos os quais receberam o tratamento especificado. Na... / Abstract: Introduction: Cirrhosis is the final stage of liver disease mainly caused by viral hepatitis, alcohol intake, and currently it can only be reversed by liver transplantation. In a new assessment of mortality of liver cirrhosis by design Global Burden of Disease (GBD) in the BMC Medicine, a variety of methods and data sources has led to an overall estimate of just over a million deaths in 2010, which was about 2% of all deaths. In recent years, research has intensified on biotech issues, favoring therapeutic discovery of stem cells to cirrhosis, which have generated great expectations in tissue regeneration of the liver and its application. However, a major problem faced was its low setting in cirrhotic liver, with spread to the whole body and without the expected effectiveness. The investigations have not yet found a way to effectively prevent stem cells spread to other organs reducing their effectiveness regeneration. AIM: Evaluate the fibrin glue derived from snake venom (SFDPS) as a scaffold for stem cells in cirrhotic livers. Methods: The model of experimental cirrhosis in rats was induced by Thioacetamide (C2H5NS), twice per week intraperitoneally (iv) at 200 mg / kg. The of blood collection was performed for biochemical analysis in B200 equipment. Isolation of stem cells was performed according Gasparotto et al. 2014. The markup for cytometry was performed on the second pass with markers RT1 AW2 FITC, CLASS RT1 PE, CD11b, CD44, CD90, CD34, CD105, CD73, CD45, ICAM. The biomarker of serine protease was performed with Alexa Fluor 488 Protein Labeling Kit (A30006v) kit. The surgery has been realized with inhalational anesthesia, the animals were separated into three groups where they received the treatment selected. Histology of 5μm sections were hematoxylin and eosin for staining (HE) and Picrosirius. Immunostaining was performed according to kit Click-it ® Imaging kits EdU. RESULTS: The development of cirrhosis was macroscopically ... / Mestre

Portal fibroblasts are newly discovered liver cells that may be of particular importance in biliary fibrosis. Recent data indicate that portal fibroblasts express NTPDase2, an ecto-nucleoside triphosphate diphosphohydrolase. Portal fibroblasts exist within the peri-portal regions of rat livers and express NTPDase2 adjacent to the basolateral side of intrahepatic bile ducts. Because extracellular nucleotides regulate secretion via activation of P2Y purinergic receptors, extracellular nucleotide hydrolysis via NTPDase2 makes NTPDase2 a potential regulator of bile ductular secretion. We propose that NTPDase2 expression may be altered in biliary fibrosis, especially in conditions in which bile duct epithelia are the target of disease. To test this hypothesis we have contrasted the distribution of NTPDase2 in normal and diseased liver states. Using confocal immunofluorescence, we assessed differences in expression of NTPDase2 in liver biopsy specimens from normal liver, primary biliary cirrhosis (PBC), and hepatitis C (HepC). We found that NTPDase2 was down regulated in the peri-portal regions of patients with PBC when compared to normal patients. Hepatitis C, however, showed NTPDase2 staining equal to or nearly equal to that of normal liver. The intermediate filament vimentin was down regulated in both PBC and Hep C when compared to normal liver. We conclude that NTPDase2 expression is down regulated in PBC but not Hep C, while vimentin is down regulated in both disease states when compared to normal liver.

Autopsy liver material from patients having died of chronic liver disease, cirrhosis, hepatocellular carcinoma (HCC) and causes unrelated to liver diseases was examined by dot blot hybridisation for the presence of HBV DNA. The results indicate that of the patients with chronic liver disease 6/9 were positive for HBV DNA in the liver tissue; of the patients with HCC 3/4 were positive for HBV DNA; of the patients with cirrhosis 4/4 showed the presence of HBV DNA in the liver. Thus by this technique 13/17 (76%) of these patients, all of whom were HBsAg positive, were shown to have HBV DNA present in liver tissue. However, autopsy liver samples were found to be unsuitable for Southern blot hybridisation. Biopsy liver/tumour tissue was examined for the presence of integrated or non-integrated HBV DNA by Southern blot analysis using the enzymes Eco R1 and Hind 111. 5/5 patients who were both HBsAg and HBeAg positive had extrachromosomal HBV DNA and 2/5 also showed the presence of integrated HBV DNA. 3/4 patients who were HBsAg positive and HBeAg negative had extrachromosomal HBV DNA and all three also had integrated HBV DNA. One control patient was negative for both markers and also for Southern blot hybridisation with the HBV DNA probe. These results support the hypothesis that HBV is a factor in the development of HCC, and indicate that the dot blot hybridisation method would be suitable for routine evaluation of patients with chronic liver disease or cirrhosis. / Thesis (M. Med.)-University of Natal, Durban, 1987.