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Análise dos fatores de risco para peritonite bacteriana espontânea em pacientes cirróticos e do perfil da flora infectante com o uso de antibióticos profiláticos / Analysis of risk factors for spontaneous bacterial peritonitis in cirrhotic patients and the ascitic fluid microbiology with use of prophylactic antibioticsValdinélia Bomfim Barban Sposeto 28 May 2009 (has links)
INTRODUÇÃO: A realização de procedimentos invasivos e o comprometimento da função hepática têm sido apontados como importantes fatores predisponentes à peritonite bacteriana primária (PBE) em pacientes cirróticos. Apesar das bactérias gram-negativas ainda serem os agentes mais freqüentemente isolados, a incidência de infecção por bactérias gram positivas tem aumentado. OBJETIVOS: Analisar os fatores de risco para PBE em pacientes cirróticos e relacionar o perfil da flora infectante do líquido ascítico com o uso de antibióticos. MÉTODOS: Estudo retrospectivo de resultados de 1.114 paracenteses realizadas em 348 pacientes no período de 2005 a 2007 no Departamento de Gastroenterologia do Hospital das Clínicas da Universidade de São Paulo. Foram definidos dois grupos: com e sem PBE, segundo resultado da leucometria do líquido ascítico. Os seguintes fatores foram analisados: aspartato aminotransferase (AST); alanina aminotransferase (ALT); bilirrubinas totais; INR; creatinina; uso do propranolol e sua resposta hemodinâmica; antecedente de hemorragia digestiva alta; choque hipovolêmico; tratamento endoscópico de varizes de esôfago; sondagem vesical; cateteres intravenosos; gravidade da doença hepática (escores de Child-Pugh, MELD e MELD-Na); infecções associadas e o perfil da flora infectante, segundo o uso de antibióticos. RESULTADOS: 852 paracenteses em 303 pacientes foram incluídas. A etiologia mais freqüente da cirrose hepática foi hepatite crônica C (25,4%), seguida por álcool (24,1%). O diagnóstico de PBE foi estabelecido em 82 (9,6%) paracenteses, 27 (33%) da forma clássica e 55 (67%) com cultura negativa. No grupo com PBE, observamos níveis mais elevados de bilirrubinas totais e INR (p<0,0001 e p= 0,0016, respectivamente). Não houve diferença entre os grupos, quanto ao uso de betabloqueadores e risco de PBE (32,9% versus 37,3%, p=0,533) e a resposta hemodinâmica ao propranolol (68,2% versus 70%, p=1,00), assim como em relação às seguintes variáveis: hemorragia digestiva alta (6,1% versus 2,5%, p=0,074), escleroterapia endoscópica (2,4% versus 0,8%, p=0,178), sondagem vesical (4,9% versus 2,3%, p=0,138), cateterismo venoso (2,4% versus 1,7%, p= 0,649). O grupo com PBE apresentou maior percentual de pacientes Child C, 51% versus 37%, (p=0,022) e maior frequência de choque hipovolêmico 2,5% versus 0,3% (p=0,0484). Não houve diferença quanto às infecções associadas (p=1,00). No grupo com PBE, as bactérias gram-positivas foram isoladas em 55,6% e as gram-negativas em 44,4% (p=0,3848). Não houve relação entre a presença de infecção por gram positivos e o uso de quinolonas (p=1,00). O aumento de um ponto no escore MELD aumentou o risco de infecção em 1,059 vezes [IC 95% : 1,0266; 1,0930] ou 6%. Não houve diferença no risco de PBE quando analisamos faixas de valores do MELD. O aumento de um ponto no MELD-Na aumentou o risco de infecção em 1,0283 vezes [IC 95%: 1,0073; 1,0497] ou 2,8%. Entretanto, o aumento de um ponto de MELD-Na na faixa entre 6 e 15 aumentou a probabilidade de infecção em 1,3371vezes [IC 95%: 1,0230; 1,7476], entre 16 e 24 aumentou em 3,2371 vezes [IC 95%: 0,1958; 53,5291] e acima de 24 pontos em 14,2663 vezes [IC 95%: 1,2441; 163,5990]. CONCLUSÕES: Pacientes com PBE apresentaram níveis mais elevados das bilirrubinas e de INR, maior frequência de choque hipovolêmico e maior gravidade da cirrose hepática, avaliada pelos escores Child-Pugh, MELD e MELD-Na, sendo o declínio da função hepática, o principal fator de risco para desenvolvimento de PBE. O uso de betabloqueadores e a resposta hemodinâmica ao propranolol não foram associados à proteção contra PBE. O MELD-Na discriminou o risco de infecção em faixas de pontuação e de gravidade. Não houve diferença significante na frequência de infecção por bactérias gram positivas e gram negativas nos pacientes com PBE. Não observamos relação entre a frequência de infecção por gram positivos e uso de quinolonas / INTRODUCTION: Invasive procedures and the decline of the liver function have been considered predisposing factors for spontaneous bacterial peritonitis (SBP) in cirrhotic patients. In spite of the predominance of gram negative, the incidence of gram positive agents is increasing in literature. OBJETIVES: To analyze the risk factors for SBP in cirrhotic patients and to assess if there is increase in the frequency of infection by gram positive agents, according to the use of antibiotics. METHODS: In this retrospective study, the results of 1.114 paracentesis carried out in 348 patients from 2005 to 2007 in the Department of Gastroenterology of the University of São Paulo were enrolled. According to the result of ascitic fluid leucometry, two groups were formed: with and without SBP. The following factors were assessed: aspartate aminotransferase; alanine aminotransferase; bilirubin; INR; creatinine; use of propranolol and hemodynamic response; previous gastrointestinal hemorrhage; hypovolemic shock; endoscopic therapy of esophageal varices; vesical catheter, indwelling vascular catheter, severity of the underlying liver disease (scores Child-Pugh, MELD and MELD-Na); concurrent bacterial infections and the frequency of gram positive bacteria according to the use of antibiotics. RESULTS: 852 paracentesis performed in 303 patients were included. The most prevalent etiology of cirrhosis was hepatitis C virus infection (25.4%), followed by alcoholic (24.1%). The diagnosis of SBP was established in 82 (9.6%) paracentesis, 27 (33%) of them were classical SBP and 55 (67%) were negative-culture SBP. In the SBP group, we found higher levels of bilirubin and more enlarged INR (p<0.0001 e p= 0.0016, respectively). There was no difference between the groups regarding the risk of SBP and the use of betablockers (32.9% versus 37.3%, p=0.533) or hemodynamic response to propranolol therapy (68.2% versus 70%, p=1.00). The following parameters did not reach statistical significance: gastrointestinal bleeding (6.1% versus 2.5%, p=0.074), endoscopic sclerotherapy of varices (2.4% versus 0.8%, p=0.78), vesical catheters (4.9% versus 2.3%, p=0.138), vascular catheters (2.4% versus 1.7%, p= 0.649). The SBP group had a higher frequency of Child C status patients, 51% versus 37%, (p=0.022) and higher frequency of hypovolemic shock 2.5% versus 0.3% (p=0.0484). There was no difference in the frequency of SBP in patients with or without concurrent bacterial infections (p=1,00). In the SBP group, gram positive staining bacteria were found in 55.6% and gram negative in 44.4% (p=0.3848). We found no relationship between gram positive bacteria infection and the use of quinolones (p=1.00). Every single point increased in the MELD score increased the risk of SBP in 1.059 times [95% IC: 1.0266; 1.0930] or by 6%. There was no significant difference in the odds ratio for SBP according to the stratification of MELD values. Every single point increased in the MELD-Na increased the risk of infection in 1.0283 times [95% IC: 1.0073; 1.0497] or 2.8%. Nevertheless, every point increased in the MELDNa between 6 and 15 increased the probability of infection in 1.3371 times [95%] IC: 1.0230; 1.7476], between 16 and 24 in 3.2371 times [95% IC: 0.1958; 53.5291] and higher than 24 points in 14.2663 times [95% IC: 1.2441; 163.5990]. CONCLUSIONS: Patients with SBP had higher levels of bilirubin and INR, higher frequency of hypovolemic shock and more severe underlying liver cirrhosis, as assessed by the Child-Pugh score, MELD and MELD-Na, indicating that the decline of the liver function is the main risk factor for developing SBP in cirrhosis. The use of betablockers and the hemodynamic response to propranolol were not associated to protection against developing SBP. The odds ratios for developing SBP increased according to the stratification of MELD-Na values, but not according to MELD stratification. There was no significant difference in the frequency of gram positive and gram negative infections in patients with SBP. The use of quinolones was not associated with increased frequency of gram positive infections in this series .
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Transition de l'immunité innée à l'immunité adaptative au cours des maladies chroniques du foie: implication de l'axe "Pattern recognition" récepteurs - Interleukine-6-Th17 / Transition from innate to adaptive immunity in chronic liver diseases: involvment of the axis "Pattern Recognition Receptors" - Interleukin-6-Th17Lemmers, Arnaud 26 May 2009 (has links)
La muqueuse intestinale puis le foie sont en contact récurrent avec la flore microbienne issue du tube digestif. L’activation des récepteurs reconnaissant des motifs moléculaires microbiens (PRR :Pattern Recognition Receptors) constitue l’élément initial de la réponse inflammatoire de l’immunité innée et oriente le type d’activation de l’immunité adaptative. La première étape entraînera l’expression de médiateurs inflammatoire (cytokines (IL-1, IL-6, TNFα), activation de la réponse de phase aiguë) et le recrutement des cellules effectrices de l’immunité innée (neutrophiles, puis monocytes). L’équilibre entre la tolérance microbienne et l’exacerbation inflammatoire afin d’éliminer l’agent microbien et menant à la destruction tissulaire permet d’atteindre la situation d’homéostasie.<p>Si l’inflammation se perpétue, par exemple en cas de défaut de clairance de l’agent microbien ou de trouble de l’intégrité de la barrière muqueuse, l’inflammation peut devenir chronique. L’IL-6 exerce alors un rôle central dans la transition de l’immunité innée à l’immunité adaptative, en modulant différentiellement l’expression de chimiokines et l’apoptose des cellules immunes menant au remplacement de l’infiltrat neutrophilique par un infiltrat lympho-monocytaire. Par ailleurs, ce climat cytokinique particulier est propice au développement de lignées spécifiques de lymphocytes tels que les lymphocytes T CD4+ sécrétant de l’IL-17 (Th17). Ceux-ci, surtout étudiés dans les défenses anti-bactériennes et fungiques, et dans les maladies autoimmunes, ont été incriminés dans les phénomènes de cytotoxicité et de renouvellement inflammatoire par l’induction d’expression de chimiokines.<p><p>Une fois la barrière intestinale franchie, le foie est le premier organe en contact avec la flore microbienne issue de l’intestin. Certains TLRs ont été démontrés impliqués dans la physiopathologie de la stéatohépatite et dans le processus de fibrose. Ce climat constant d’exposition antigénique est associé en cas de maladie chronique du foie à une exacerbation d’expression de médiateurs infammatoires (IL-1, IL-6, TNFα).<p>Nous avons étudié la modulation d’expression des différents TLRs au cours d’un modèle de maladie alcoolique du foie chez la souris. Cette étude démontrait qu’il existait une majoration d’expression des TLR1, 2, 4, 6, 7, 8 et 9 dépendante du stress oxydatif suite à l’exposition chronique du foie à l’alcool ;celle-ci entraînant davantage de lésions hépatiques lors de l’injection des ligands respectifs de ces différents TLRs.<p>Dans ce contexte, nous avons également étudié l’expression des différentes sous-unités du récepteur à l’IL-6 au cours de deux maladies chroniques du foie chez l’homme :les maladies alcooliques du foie et l’hépatite C chronique. Nous avons mis en évidence que les taux plasmatiques d’IL-6 et de la forme soluble de gp130 augmentaient au cours des maladies chroniques du foie, de manière corrélée à la sévérité. Nous avons également démontré l’effet inhibiteur de sgp130 sur la réponse de phase aiguë dépendante du trans-signaling de l’IL-6 in vitro. Ces données suggèrent que sgp130 contribue au déficit de réponse de phase aiguë observé chez les patients atteints de cirrhose. <p><p>Par ailleurs, vu le contexte « cytokinique » chronique des maladies alcooliques du foie (IL-1 et IL-6), nous avons étudié l’activation de la voie de l’interleukine-17 et des Th17 au cours des maladies alcooliques du foie chez l’homme. Nous avons mis en évidence qu’il existait une activation de cellules circulantes sécrétant de l’IL-17 (comprenant des Th17) au cours de la cirrhose alcoolique stable. Par contre, au sein du foie, l’activation de cellules sécrétant de l’IL-17 était davantage augmentée lors de l’hépatite alcoolique. Nous avons également mis en évidence que les cellules stellées (cellules responsables de la fibrose hépatique) stimulées à l’IL-17 recrutaient les neutrophiles suite à l’expression d’IL-8 et de GROα. Cette nouvelle voie inflammatoire démontrée lors d’une maladie du foie chez l’homme met en évidence l’activation de la voie de l’IL-17 au cours des maladies alcooliques du foie et sa contribution potentielle au recrutement hépatique de neutrophiles au cours de l’hépatite alcoolique aiguë. Cette voie sera explorée dans l’avenir en termes de fonctionnalité et de potentielle cible thérapeutique. <p> <p>En conclusion, tout comme le suggère la littérature pour les maladies autoimmunes (maladie de Crohn, arthrite, sclérose en plaque), il semble que les maladies alcooliques du foie partagent avec ces dernières diverses caractéristiques inflammatoires. La flore microbienne intestinale participe à la physiopathologie des lésions hépatiques, de même que l’activation de PRR (TLR). Par ailleurs, un climat inflammatoire chronique (IL-6,…), contre-régulé par certains mécanismes (sgp130), est associé à la présence périphérique et hépatique de lymphocytes Th17. Cette dernière découverte ouvre de nouvelles perspectives dans la compréhension de la physiopathologie des maladies alcooliques du foie, et peut-être de nouvelles cibles thérapeutiques concernant l’hépatite alcoolique aiguë.<p> / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
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Uticaj statusa vitamina D na metaboličku aktivnost kosti i koštanu masu kod bolesnika sa alkoholnom cirozom jetre / Effects of vitamin D status on bone metabolism and bone mass in patients with alcoholic liver cirrhosisSavić Željka 27 October 2014 (has links)
<p>Uvod: Hepatička osteodistrofija je termin koji obuhvata metaboličke bolesti kosti udružene sa hroničnim bolestima jetre. U alkoholnoj cirozi (AC) jetre postoji visoka zastupljenost deficijencije vitamina D proporcionalna stepenu disfunkcije jetre, ali njena uloga u patogenezi hepatičke osteodistrofije nije dovoljno objašnjena. Nivo 25(OH)D odražava status vitamina D. Kod AC jetre izmenjena je metabolička aktivnost kosti i suprimirano je formiranje kosti što dovodi do smanjenja koštane mase. U centru interesovanja je postizanje optimalnog statusa vitamina D. Stavovi o suplementaciji vitaminom D kod AC jetre nisu jasno definisani. Cilj rada: Utvrditi nivo vitamina D, ispitati metaboličku aktivnost kosti i mineralnu gustinu kosti kod bolesnika sa AC jetre. Utvrditi efekte suplementacije sa 1000 IU vitamina D3 na dan tokom godinu dana u odnosu na metaboličku aktivnost kosti i mineralnu gustinu kosti kod ispitivanih bolesnika. Bolesnici i metode: Istraživanje je sprovedeno na Klinici za gastroenterologiju i hepatologiju Kliničkog centra Vojvodine u Novom Sadu kao prospektivna intervencijska studija sa primenom suplementacije sa 1000 IU vitamina D3 na dan kod bolesnika sa AC jetre. Grupu bolesnika koja je uključena u istraživanje (1) činilo je 70 bolesnika muškog pola sa dijagnozom AC jetre. Bolesnici su imali četiri pregleda (P), odnosno tačke studije: P1-uključivanje bolesnika i započinjanje suplementacije vitaminom D; P2, P3 i P4 posle tri, šest i dvanaest meseci suplementacije vitaminom D, redom. Prilikom svakog pregleda rađene su analize funkcije jetre, metabolizma kosti i statusa vitamina D. Na početku (P1) i na kraju istraživanja (P4) vršeno je merenje mineralne gustine kosti (BMD) DXA metodom. Gubitak bolesnika od P1 do P4 bio je dvadeset, na različitim tačkama studije. Prvi deo istraživanja odnosi se na Grupu bolesnika koja je uključena u istraživanje (1) i završila prvi pregled (P1). Pedeset bolesnika je završilo kompletno istraživanje po predviđenom protokolu i oni se zbog realizacije svih pregleda i ponovljenih merenja posmatraju kao: Grupa bolesnika koja je završila istraživanje (2). Rezultati: (1): Kod bolesnika sa AC jetre utvrđena je deficijencija vitamina D, snižen nivo osteokalcina, normalni nivoi CrossLapsa, PTH, ukupnog i jonizovanog kalcijuma, fosfora i magnezijuma. Osteopeniju je imalo 42,65% a osteoporozu 14,71% ispitanika. Kod svih ispitanika najniži BMD izmeren je na vratu femura. (2): Suplementacija vitaminom D dovela je do značajnog porasta 25(OH)D. U odnosu na osteokalcin konstatovana je pozitivna razlika vrednosti P1/P4, iako je nivo ostao ispod donje granice normale. Kod nivoa CrossLapsa i PTH razlika P1/P4 je negativna, ali su nivoi u sva četiri merenja u okviru referentnih vrednosti. Na lumbalnoj kičmi došlo je do poboljšanja BMD za 0.87%, a pogoršanja su na vratu femura -1.87 % i kuku -1.65%. Konstatovano je i poboljšanje funkcije jetre. Zaključci: Kod bolesnika sa AC jetre poboljšanje statusa vitamina D dovodi do povećanja formiranja kosti i poboljšanja koštane mase na lumbalnoj kičmi. Neophodno je određivanje statusa vitamina D kod svih bolesnika sa AC jetre i uvođenje suplementacije vitaminom D kod bolesnika koji imaju nivo 25(OH)D < 80 nmol/l, uz tromesečne kontrole efekta. Kod postavljanja dijagnoze AC jetre potrebno je inicijalno određivanje BMD. Kod suplementacije vitaminom D nakon inicijalnog DXA pregleda sledeći se preporučuje nakon jedne do dve godine.</p> / <p>Introduction: The term Hepatic osteodystrophy defines a group of metabolic bone diseases associated with underlying chronic liver disease. Alcoholic liver cirrhosis (ALC) is characterized by high incidence of vitamin D deficiency that is proportional to the level of liver failure; however, its role in the pathogenesis of hepatic osteodystrophy has not yet been fully elucidated. The level of 25(OH)D best reflects the vitamin D status. ALC is characterized by changed bone metabolic activity and suppressed bone formation, resulting in the decrease in bone mass. The key topic of interest is the achievement of optimal vitamin D status. The attitude of health professionals towards vitamin D supplementation in alcoholic liver cirrhosis has not yet been clearly defined. The aim of the research: Determining of vitamin D levels, investigating the metabolic activity of the bone and bone mass in patients with alcoholic liver cirrhosis (ALC); Determining the effects of vitamin D3 supplementation at the dose 1000 IU/day during a one-year period in relation to metabolic activity of the bone and bone mineral density (BMD) in the investigated patient population. Patients and methods: The research was conducted at the Clinic for Gastroenterology and Hepatology of the Clinical Centre of Vojvodina in Novi Sad. The research was designed as a prospective interventional study implicating vitamin D3 supplementation at the dose 1000 IU/day to patients with ALC. The investigated patient population (1) encompassed 70 male patients diagnosed with ALC. The patients underwent four examinations (P), that is, research phases: P1 – inclusion of the patient into the study and introduction of vitamin D supplementation; P2, P3 and P4 after 3, 6 and 12 months of vitamin D supplementation treatment, respectively. Each examination included the analysis of liver function, bone metabolism and vitamin D status. At the beginning (P1) and at the end (P4) of the investigation period, bone mineral density (BMD) was measured by means of dual-energy x-ray absorptiometry (DXA) method. Twenty patients dropped out from the research at different stages throughout the investigation period (P1 to P4). The first part of the investigation pertains to the Group of patients who were included into the study (1) and completed the first examination (P1). Fifty patients have completed the entire research according to the foreseen protocol encompassing all examinations and repeated measurements. These patients are considered a Group of patients who completed the research (2) Results: (1): In ALC patients, vitamin D deficiency and decreased osteocalcin levels were established, as well as normal levels of CrossLaps, PTH, total and ionized calcium, phosphorus and magnesium. Osteopenia and osteoporosis were established in 42.65% and 14.71% of patients, respectively. The lowest BMD was measured in the femoral neck in all patients. (2): Vitamin D supplementation resulted in significant increase in 25(OH)D. Analysis of osteocalcin level revealed positive P1/P4 difference, even though the level remained below the lower normal limit. The levels of CrossLaps and PTH revealed negative P1/P4 difference; however, the levels determined at all four measurements were within the reference values. An improvement of BMD for 0.87% was established in lumbar spine, whereas a decrease was noticed in femoral neck (1.87%) and hip (1.65%). Furthermore, an improvement of liver function was established. Conclusions: Improvement of vitamin D status in ALC patients results in an increase of bone formation and improvement of body mass in lumbar spine. Determining the vitamin D status in all patients with ALC is of outmost importance, as well as the vitamin D supplementation of patients with levels of 25(OH)D < 80 nmol/l along with the monitoring of treatment outcome at three-month intervals. Establishment of the diagnosis of alcoholic liver cirrhosis should encompass initial measurement of BMD. In case of vitamin D supplementation treatment, the initial DXA examination should be repeated after the period of one to two years.</p>
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Prevalence of and Potential Influencing Factors for Alcohol Dependence in EuropeRehm, Jürgen, Anderson, Peter, Barry, Joe, Dimitrov, Plamen, Elekes, Zsuzsanna, Feijão, Fernanda, Frick, Ulrich, Gual, Antoni, Gmel, Gerrit, Kraus, Ludwig, Marmet, Simon, Raninen, Jonas, Rehm, Maximilian X., Scafato, Emanuele, Shield, Kevin D., Trapencieris, Marcis, Gmel, Gerhard 04 August 2020 (has links)
Alcohol use disorders (AUDs), and alcohol dependence (AD) in particular, are prevalent and associated with a large burden of disability and mortality. The aim of this study was to estimate prevalence of AD in the European Union (EU), Iceland, Norway, and Switzerland for the year 2010, and to investigate potential influencing factors. The 1-year prevalence of AD in the EU was estimated at 3.4% among people 18–64 years of age in Europe (women 1.7%, men 5.2%), resulting in close to 11 million affected people. Taking into account all people of all ages, AD, abuse and harmful use resulted in an estimate of 23 million affected people. Prevalence of AD varied widely between European countries, and was significantly impacted by drinking cultures and social norms. Correlations with level of drinking and other drinking variables and with major known outcomes of heavy drinking, such as liver cirrhosis or injury, were moderate. These results suggest a need to rethink the definition of AUDs.
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Messung der Lebersteifigkeit mittels der 2D-Scherwellen-Elastographie mit dem Sonographiegerät LOGIQ E9 (Firma GE Healthcare) bei gesunden Probanden, Leber-gesunden Patienten sowie Patienten mit Leberzirrhose zur Generierung von Normwerten / Measurement of liver stiffness using 2D shear wave elastography with the sonography device LOGIQ E9 (GE Healthcare) in healthy subjects, liver-healthy patients and patients with cirrhosis to generate normal valuesHofer, Johannes Albertus 16 June 2020 (has links)
No description available.
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Risikofaktoren für Blutungskomplikationen nach ÖsophagusvarizenligaturGrothaus, Johannes 03 May 2012 (has links)
Esophageal varices are expanded veins of the submucosa that develop in patients with portal hypertension. They develop as collaterals between the portal vein and the superior vena cava. Varices are seen when the HPVG rises >12mmHG and can lead to a life-threatening bleeding episode. Endoscopic band ligation (EBL) is the treatment of choice of acute variceal bleeding. It is also performed for primary and secondary prophylaxis of bleeding from esophageal varices. After EBL, patients are at risk of postinterventional bleeding. Therefore, patients are often hospitalized until endoscopy proves all applied ligation bands have dropped off. At present, there is no standardized algorithm for surveillance of patients after EBL. Furthermore, risk factors for bleeding complications after EBL are poorly evaluated. The available studies mostly investigated patient collectives .after endoscopic sclerotherapy. The aim of this study was to investigate bleeding behaviour after EBL, to make recommendations for in- and out-patient surveillance after EBL and to analyze independent risk factors for bleeding complications after EBL.
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The Mechanistic Role and Therapeutic Potential of microRNA-122 in Alcoholic Liver Disease: A DissertationSatishchandran, Abhishek 07 April 2016 (has links)
Chronic alcohol use results in accelerated liver injury, leading to alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma. However, due to the complex nature of this disease process, a central, druggable mechanism has remained elusive. microRNAs are potent post-transcriptional regulators of gene expression. A single miRNA has the ability to regulate hundreds of pathways simultaneously, defining cellular fate and function. microRNA-122 (miR-122), the most abundant miRNA in hepatocytes, has a demonstrated role as an tumor suppressor, regulator of hepatocyte metabolism, and hepatic differentiation.
In this dissertation I demonstrate the role of miR-122 on alcoholic liver disease (ALD) pathogenesis over four parts. In chapter II, I will demonstrate chronic alcoholic patients, free of neoplastic changes, have a reduction of miR-122 and that this miRNA regulates HIF-1α, a determinant of ALD pathogenesis. In chapter III, using hepatocytetropic adeno-associated virus 8 (AAV8) vector, I demonstrate that miR-122 inhibition mimics ALD pathogenesis, and furthermore, using hepatocyte-specific HIF-1α-null (HIF1hepKO) mice that this phenomenon is HIF-1α dependent. Given this finding, in chapter IV, I demonstrate that ectopic expression of miR-122 in vivo can reverse alcoholinduced liver damage, steatosis, and inflammation by directly targeting HIF-1α. Finally, in chapter V, I present evidence that alcohol-induced dysregulation of grainyhead-like proteins 1 and 2 (GRHL2), mediate the inhibition of miR-122 at the transcriptional level. These findings dissect a novel mechanistic regulatory axis of miR-122 and indicate a potential opportunity for restoration of miR-122 as a therapy in early ALD.
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Funktionelle Analyse von komplexen Hepatitis-B-Virus-Varianten, assoziiert mit Leberzirrhose bei ImmunsupprimiertenMärschenz, Stefanie 06 October 2006 (has links)
Obwohl der Wildtyp des Hepatitis-B-Virus (HBV) nicht zytopathogen und die Pathogenese der Hepatitis B generell immunvermittelt ist, können in immunsupprimierten Nierentransplantatempfängern mit chronischer Hepatitis B schwere Leberschäden bis hin zu Leberzirrhose und Leberversagen entstehen. Die Entwicklung von Leberzirrhose in den Nierentransplantierten ist assoziiert mit der Akkumulation und Persistenz von komplexen HBV-Varianten mit Mutationen im Core-Promotor / X-Gen, Deletionen im Core (C)-Gen und teilweise zusätzlichen Deletionen im präS-Bereich. Dies lässt eine Rolle der Varianten in der speziellen Pathogenese bei Immunsupprimierten vermuten. In der vorliegenden Arbeit wurden funktionelle Analysen der komplexen Varianten im Vergleich zu Referenz-Wildtypgenomen und Wildtyp-ähnlichen Genomen der Patienten aus der frühen Infektionsphase durchgeführt, um Hinweise auf den potentiellen Beitrag der Varianten zur Pathogenese zu erlangen. Die Analysen erfolgten durch transiente Transfektion der humanen Hepatomazelllinie HuH7 mit repräsentativen HBV-Gesamtgenomen, die aus 2 Patienten während des Krankheitsverlaufs von einer asymptomatischen Infektion hin zur Leberzirrhose isoliert und kloniert worden waren. Trotz einiger Unterschiede im Detail wiesen die komplexen Varianten einen gemeinsamen, drastisch vom Wildtyp abweichenden Phänotyp auf. Dieser war gekennzeichnet durch eine veränderte Transkription mit reduzierten präC- und Oberflächen-mRNAs und verstärkter Expression der prägenomischen RNA, eine starke Reduktion des häufigsten Spleißprodukts der prägenomischen RNA, SP1, eine extrem reduzierte oder fehlende Expression und/oder Sekretion aller Oberflächenproteine und des HBeAg, ein verändertes intrazelluläres Verteilungsmuster des schwach exprimierten Core-Proteins und teilweise der Oberflächenproteine sowie eine erhöhte Replikation und Anreicherung gegenüber Wildtyp-HBV aufgrund einer verstärkten reversen Transkription der prägenomischen RNA. Dieser Phänotyp basierte zum Teil auf den Mutationen in Core-Promotor und C-Gen, wurde jedoch deutlich durch zusätzliche Mutationen in den übrigen Genomabschnitten beeinflusst. Die vielfältigen Veränderungen der Varianten unterstützen ihren vermuteten Beitrag zur Pathogenese. / Although wild-type hepatitis B virus is not cytopathogenic and the pathogenesis of hepatitis B is generally immune mediated, also immuno-suppressed patients, such as renal transplant recipients, with chronic hepatitis B may develop liver cirrhosis and end-stage liver disease. In renal transplant recipients, the development of liver cirrhosis is associated with the accumulation and persistence of complex HBV variants with mutations in core promoter / X gene, deletions in core (C) gene and sometimes additional deletions in the preS region. This suggests a role of these variants in the special pathogenesis in immuno-suppressed patients. In the present work, the complex variants were functionally analyzed in comparison to reference wild-type genomes and wild-type-like HBV genomes from the early asymptomatic phase of infection. For the analyses, representative cloned full-length HBV genomes isolated from 2 patients before and during liver cirrhosis were transiently transfected into the human hepatoma cell line HuH7. In spite of some variations, the complex variants showed a common phenotype, which was drastically altered compared to wild-type. It was characterized by reduced preC and surface mRNAs and increased expression of pregenomic RNA, by a strong reduction of the major spliced pregenomic RNA, SP1, by a partial or complete defect in expression and/or secretion of surface proteins and HBeAg, by an aberrant intracellular localization of the weakly expressed core protein and in some cases of the surface proteins, and by an enhanced replication and enrichment over wild-type HBV due to an enhanced reverse transcription of variant pregenomic RNA. The phenotypic alterations were often based on the mutations in core promoter and C gene but were considerably influenced by the additional mutations in other genomic regions. The multiple functional changes of the variants support their assumed contribution to pathogenesis.
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Padrões histopatológicos e deposição de colágenos durante a progressão da fibrose hepática como fatores prognósticos da atresia de vias biliares / Histopathological and collagens deposition patterns during hepatic fibrosis progression as prognostic factors in biliary atresiaSantos, Luis Ricardo Longo dos 16 June 2015 (has links)
Atresia de vias biliares (AVB) é uma hepatopatia colestática específica da criança, de etiologia desconhecida, com evolução para fibrose hepática precoce. AVB é a principal causa de cirrose na infância e principal indicação de transplante hepático pediátrico (Tx). Compreender os fatores envolvidos na progressão da fibrose é fundamental para estabelecer tratamentos efetivos nas hepatopatias crônicas. Identificar padrões histopatológicos associados ao prognóstico da AVB permitiria melhor planejamento dos centros de transplante e adequado aconselhamento familiar. OBJETIVO: Estabelecer padrões de marcadores histopatológicos e de imunofluorescência para colágenos em biópsias hepáticas iniciais e finais de pacientes com AVB submetidos a tratamento cirúrgico. Correlacionar esses marcadores com o prognóstico da doença, definido com base no tempo de evolução até realização do Tx. MÉTODO: Avaliação histológica de alterações biliares e fibrose hepática e histomorfometria da fibrose marcada por picrossírius e da deposição dos colágenos tipos I, III, IV e V marcados por imunofluorescência indireta (IF), em biópsias hepáticas iniciais e finais de 36 pacientes com AVB submetidos à hepatoportoenterostomia de Kasai (KPE) e ao Tx nos últimos 20 anos em nossa instituição. RESULTADOS: A mediana das idades de realização da KPE foi de 12,5 semanas (6-20) e do Tx foi de 27 meses (6-120). Reação ductular e malformação de placa ductal foram mais intensas nas biópsias iniciais (p < 0,05), enquanto fibrose hepática e ductopenia apresentaram padrão progressivo (p < 0,001), sem correlações com a idade de realização da KPE nem com o tempo de evolução até Tx. A morfometria da fibrose hepática marcada pelo picrossírius nas biópsias iniciais apresentou correlação positiva com a idade da KPE (p = 0,01), mas não com a idade do Tx (p = 0,24). A deposição perissinusoidal dos colágenos dos tipos III e V foi mais intensa nas biópsias iniciais (p < 0,01), enquanto os colágenos dos tipos I e IV apresentaram padrão de deposição progressiva (p < 0,01). Pacientes com maior deposição perissinusoidal de colágeno tipo I nas biópsias iniciais apresentaram curva de tempo de evolução até Tx sugerindo pior prognóstico (p = 0,04). CONCLUSÃO: Marcadores histopatológicos de alterações biliares, fibrose hepática e deposição de colágenos apresentaram características evolutivas distintas nas fases inicial e final da AVB, sem correlação com o tempo de evolução até Tx. A morfometria da deposição perissinusoidal de colágeno tipo I em biopsias iniciais marcadas por IF pode ser correlacionada ao tempo de evolução até Tx em pacientes com AVB operada / Biliary atresia (BA) is a specific cholestatic liver disease of unknown etiology that affects children and progresses to early hepatic fibrosis. BA is the main indication of pediatric liver transplantation (LTx). Understanding the factors involved in the progress of fibrosis is essential to establish effective treatment to chronic liver disease. Histopathological markers in liver biopsies could be useful to predict progression to end stage disease and to make it possible to improve planning in transplantation centers and parental orientation. OBJECTIVE: To establish histopathological or immunohistochemical markers in initial or final liver biopsies of BA patients and correlate those markers with prognosis, as defined by progression time lapse until LTx. METHOD: Histological analysis of multiple parameters of biliary alterations and morphometrical assessment of liver fibrosis were performed, besides indirect immunofluorescence assays (IF) for type I, III, IV and V collagens in initial and final liver biopsies of 36 patients with BA submitted to Kasai hepatoportoenterostomy (KPE) and LTx in the last 20 years in a single center. RESULTS: The median of the ages at KPE was 12.5 weeks (6-20) and at LTx was 27 months (6-120). Ductular reaction and ductal plate malformation were more severe in the initial biopsies (p < 0.05), while ductopenia and liver fibrosis were more severe in final biopsies (p < 0.001), though without correlation with age at KPE nor with progression time lapse until LTx. Morphometrical assessment of liver fibrosis marked by picrosirius red in initial biopsies demonstrated positive correlation with age at KPE (p = 0.01) but not with age at LTx (p = 0.24). The perisinusoidal deposition of type III and V collagens was more extended in the initial biopsies (p < 0.01), while type I and IV collagens deposition indicated progression (p < 0.01). Patients with large amounts of perisinusoidal type I collagen in the initial biopsies had worse progression time curve until LTx (p = 0.04). CONCLUSION: Biliary alterations, liver fibrosis and collagens deposition demonstrated distinctive progression findings in the initial or final phases of the BA, without prognostic correlation. Morphometrical assessment of perisinusoidal deposition of type I collagen by IF in the initial biopsies can be correlated with progression time until LTx in patients with post-surgical BA
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Padrões histopatológicos e deposição de colágenos durante a progressão da fibrose hepática como fatores prognósticos da atresia de vias biliares / Histopathological and collagens deposition patterns during hepatic fibrosis progression as prognostic factors in biliary atresiaLuis Ricardo Longo dos Santos 16 June 2015 (has links)
Atresia de vias biliares (AVB) é uma hepatopatia colestática específica da criança, de etiologia desconhecida, com evolução para fibrose hepática precoce. AVB é a principal causa de cirrose na infância e principal indicação de transplante hepático pediátrico (Tx). Compreender os fatores envolvidos na progressão da fibrose é fundamental para estabelecer tratamentos efetivos nas hepatopatias crônicas. Identificar padrões histopatológicos associados ao prognóstico da AVB permitiria melhor planejamento dos centros de transplante e adequado aconselhamento familiar. OBJETIVO: Estabelecer padrões de marcadores histopatológicos e de imunofluorescência para colágenos em biópsias hepáticas iniciais e finais de pacientes com AVB submetidos a tratamento cirúrgico. Correlacionar esses marcadores com o prognóstico da doença, definido com base no tempo de evolução até realização do Tx. MÉTODO: Avaliação histológica de alterações biliares e fibrose hepática e histomorfometria da fibrose marcada por picrossírius e da deposição dos colágenos tipos I, III, IV e V marcados por imunofluorescência indireta (IF), em biópsias hepáticas iniciais e finais de 36 pacientes com AVB submetidos à hepatoportoenterostomia de Kasai (KPE) e ao Tx nos últimos 20 anos em nossa instituição. RESULTADOS: A mediana das idades de realização da KPE foi de 12,5 semanas (6-20) e do Tx foi de 27 meses (6-120). Reação ductular e malformação de placa ductal foram mais intensas nas biópsias iniciais (p < 0,05), enquanto fibrose hepática e ductopenia apresentaram padrão progressivo (p < 0,001), sem correlações com a idade de realização da KPE nem com o tempo de evolução até Tx. A morfometria da fibrose hepática marcada pelo picrossírius nas biópsias iniciais apresentou correlação positiva com a idade da KPE (p = 0,01), mas não com a idade do Tx (p = 0,24). A deposição perissinusoidal dos colágenos dos tipos III e V foi mais intensa nas biópsias iniciais (p < 0,01), enquanto os colágenos dos tipos I e IV apresentaram padrão de deposição progressiva (p < 0,01). Pacientes com maior deposição perissinusoidal de colágeno tipo I nas biópsias iniciais apresentaram curva de tempo de evolução até Tx sugerindo pior prognóstico (p = 0,04). CONCLUSÃO: Marcadores histopatológicos de alterações biliares, fibrose hepática e deposição de colágenos apresentaram características evolutivas distintas nas fases inicial e final da AVB, sem correlação com o tempo de evolução até Tx. A morfometria da deposição perissinusoidal de colágeno tipo I em biopsias iniciais marcadas por IF pode ser correlacionada ao tempo de evolução até Tx em pacientes com AVB operada / Biliary atresia (BA) is a specific cholestatic liver disease of unknown etiology that affects children and progresses to early hepatic fibrosis. BA is the main indication of pediatric liver transplantation (LTx). Understanding the factors involved in the progress of fibrosis is essential to establish effective treatment to chronic liver disease. Histopathological markers in liver biopsies could be useful to predict progression to end stage disease and to make it possible to improve planning in transplantation centers and parental orientation. OBJECTIVE: To establish histopathological or immunohistochemical markers in initial or final liver biopsies of BA patients and correlate those markers with prognosis, as defined by progression time lapse until LTx. METHOD: Histological analysis of multiple parameters of biliary alterations and morphometrical assessment of liver fibrosis were performed, besides indirect immunofluorescence assays (IF) for type I, III, IV and V collagens in initial and final liver biopsies of 36 patients with BA submitted to Kasai hepatoportoenterostomy (KPE) and LTx in the last 20 years in a single center. RESULTS: The median of the ages at KPE was 12.5 weeks (6-20) and at LTx was 27 months (6-120). Ductular reaction and ductal plate malformation were more severe in the initial biopsies (p < 0.05), while ductopenia and liver fibrosis were more severe in final biopsies (p < 0.001), though without correlation with age at KPE nor with progression time lapse until LTx. Morphometrical assessment of liver fibrosis marked by picrosirius red in initial biopsies demonstrated positive correlation with age at KPE (p = 0.01) but not with age at LTx (p = 0.24). The perisinusoidal deposition of type III and V collagens was more extended in the initial biopsies (p < 0.01), while type I and IV collagens deposition indicated progression (p < 0.01). Patients with large amounts of perisinusoidal type I collagen in the initial biopsies had worse progression time curve until LTx (p = 0.04). CONCLUSION: Biliary alterations, liver fibrosis and collagens deposition demonstrated distinctive progression findings in the initial or final phases of the BA, without prognostic correlation. Morphometrical assessment of perisinusoidal deposition of type I collagen by IF in the initial biopsies can be correlated with progression time until LTx in patients with post-surgical BA
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