A fibrose hepática resulta da cronicidade da injúria celular, ocasionando acúmulo dos componentes da matriz extracelular (MEC) pela ativação, principalmente, de células estreladas e fibroblastos portais em miofibroblastos. Estas células se conectam através de junções comunicantes do tipo gap, formadas por proteínas denominadas conexinas (Cx). As junções gap são responsáveis pelo fluxo de moléculas e íons entre as células, desempenhando importante função no controle da homeostasia tecidual. Diversos tipos de conexinas foram descritas nas células hepáticas. Os hepatócitos expressam Cx32 e Cx26, enquanto as demais células não-parenquimatosas expressam Cx43. Alguns estudos analisaram a expressão das conexinas e das junções gap em processos de reparação e fibrogênese em diferentes tecidos, no entanto, poucos avaliaram seu papel na fibrogênese hepática. Sendo assim, o objetivo deste estudo foi avaliar os aspectos morfológicos, histopatológicos e moleculares da fibrose hepática, induzida por tetracloreto de carbono (CCl4), em animais deficientes para as conexinas 43 (Cx43+/-) ou 32 (Cx32-/-). Foram analisados dados biométricos, histopatológicos, ultra-estruturais, imuno-histoquímicos e bioquímicos, além da expressão gênica e protéica das conexinas. Os aspectos moleculares da fibrose hepática foram analisados pela expressão de genes relacionados com a deposição e degradação da matriz extracelular por PCR em tempo real. As análises macroscópicas e de varredura demonstraram um processo de micronodulação da superfície hepática mais acentuado nos camundongos Cx43+/- fibróticos em relação aos animais wild-type (Cx43+/+) fibróticos. Adicionalmente, estes animais apresentaram maior proporção volumétrica de colágeno no tecido hepático; redução na atividade necroinflamatória tecidual; redução nas concentrações séricas de AST e ALT; redução na proliferação celular dos hepatócitos e redução na expressão dos genes: colágeno tipo I, TGFβ-1, MMP-2, MMP-13 e TIMP-1. Por sua vez, os camundongos Cx32-/- fibróticos apresentaram aumento na deposição de colágeno no parênquima hepático; aumento na atividade necroinflamatória tecidual e aumento nos níveis séricos das enzimas hepáticas AST, ALT e fosfatase alcalina em comparação aos animais wild-type (Cx32+/+) fibróticos. Também foram observadas redução na proliferação hepatocelular e maior quantidade de corpúsculos apoptóticos no tecido hepático. Baseando-se em todos os resultados obtidos, observou-se que ambos os modelos animais apresentaram aumento da fibrose hepática, aparentemente ocasionada por diferentes modos de ação. Os animais deficientes em Cx43 apresentaram menor capacidade de degradação do colágeno, ocasionando seu acúmulo no tecido hepático. Por outro lado, os animais deficientes em Cx32 apresentaram maior deposição de colágeno em resposta à injúria hepatocelular mais acentuada, aliada ao desequilíbrio entre as taxas de proliferação celular e apoptose. Em conclusão, os resultados obtidos neste trabalho demonstraram a importante participação das conexinas no controle da fibrogênese hepática, e que podem representar potenciais alvos terapêuticos para o tratamento das doenças hepáticas crônicas em humanos e animais. / Hepatic fibrosis results from chronic cell injury, leading to accumulation of components of extracellular matrix (ECM) through activation mainly of hepatic stellate cells and portal fibroblasts into myofibroblasts. These cells communicate through intercellular gap junctions composed of proteins known as connexins (Cx). Gap junctions are responsible for the exchange of molecules and ions among cells, playing an important role in the control of tissue homeostasis. Several subtypes of connexins were described among hepatic cells. Hepatocytes express Cx32 and Cx26, while the other non-parenchymal cells express Cx43. Some studies analyzed the expression of connexins and gap junctions on processes of healing and fibrogenesis in different tissues; however, few studies evaluated its role on hepatic fibrogenesis. Thus, the objective of this study was to evaluate morphological, histopathological and molecular aspects of hepatic fibrosis induced by carbon tetrachloride (CCl4) in animals with connexin 43 (Cx43+/-) or 32 (Cx32-/-) deficiency. We analyzed biometric, histopathological, ultrastructural, immunohistochemical and biochemical data, besides gene and protein expression of connexins. Molecular aspects of hepatic fibrosis were analyzed with the expression of genes related to deposition and degradation of extracellular matrix by real time PCR. Macroscopic and Scanning Electron Microscopy analyses showed a process of micronodulation of hepatic surface more accentuated on Cx43+/- fibrotic mice when compared to fibrotic wild-type (Cx43+/+) animals. Additionally, these animals presented a higher collagen volumetric proportion on hepatic tissue; reduction of tissue necroinflammatory activity; reduction of serum AST and ALT; reduction of hepatocytes proliferation and reduction of expression type I collagen, TGFβ-1, MMP-2, MMP-13 and TIMP-1 genes. Fibrotic Cx32-/- mice presented an increase of collagen deposition in hepatic parenchyma; increase of tissue necro-inflammatory activity and increase of liver enzymes AST, ALT and alkaline phosphatase when compared to fibrotic wild-type (Cx32+/+) animals. Reduction of hepatocellular proliferation and a higher amount of apoptotic bodies on hepatic tissue were also observed. Based on the results obtained, we observed that both animal models showed an increase of hepatic fibrosis, apparently caused by different modes of action. Cx43 deficient animals showed a reduced capacity to degrade collagen, causing its accumulation in the hepatic tissue. Cx32 deficient animals showed an increased collagen deposition in response to accentuated hepatocellular injury, together to an unbalance between rates of cellular proliferation and apoptosis. In conclusion, results obtained on this study demonstrate an important role of connexins on the control of hepatic fibrogenesis, which could represent potential therapeutical targets for the treatment of chronic liver diseases in humans and animals.

Glomerulonephritis as an extra hepatic manifestation of chronic HBV infection has now been well documented [1,2,3,4,5]. HBV-associated nephropathy has been described in areas of both high and low endemicity [6]. In Africa HBV-associated nephropathy has been reported from the southern, central and northern regions [7,8,9,10,11]. In the southern African continent the prevalence of HBV-associated nephropathy appears to be higher than the rest of the continent [12]. In KwaZulu/Natal, South Africa, the prevalence of hepatitis B surface antigenaemia (HbsAg) in urban, rural and institutionalised children was reported to be 6.3%, 18.5% and 35.4% and the HBV exposure rates, as shown by the presence of any marker of HBV infection, 19.5%, 65.1% and 70.1% respectively amongst black children [13]. Prior experience of nephrotic syndrome (NS) and its association with HBV in black children, already published in a series of reports, showed HBV-associated nephropathy to be the commonest form of nephrotic syndrome among black patients in KwaZulu/Natal; membranous nephropathy (MN) being the commonest histological type reported [7,14]. The only other large series of HBV-associated nephropathy in southern Africa was from Cape Town of a large cohort of children, mainly of mixed ancestory (coloured), with a small number of black children [8]. There have been no other large studies of this condition amongst black children in Africa. We therefore undertook a series of studies to delineate the spectrum of this disease in black children with regard to the following: clinical presentation, laboratory findings, natural history, biosocial background, genetics (using HLA Class I and II antigens) as well as the impact of treatment and prevention by immunisation. We commenced these studies by reviewing our 20-year experience of 636 children with NS in Durban, South Africa for the period 1976- - 1995. Three hundred and six (48.2%) were blacks, 307 (48.2%) Indians and 23 (3.6%) were a mixed group (coloured); 91 (14.3%) could not be categorised and were excluded from the analysis. In black children, membranous nephropathy accounted for 43% of all cases of NS; 86.2% of these 306 children were associated with hepatitis B virus antigens [15]. This contrasts with the 2% - 5% prevalence of idiopathic membranous nephropathy reported in western countries [16]. We then proceeded to document the clinical features of this disease in black children. One hundred and thirty-three children with NS positive for HBV carriage were studied. In 70 patients the histological type was membranous; 46 of these 70 patients were followed up for a mean of 3.4 years (range 1-11). Spontaneous elimination of both HBsAg and HBeAg occurred in 10 (21.7%) of the 46 patients; 16 (34.8%) cleared HBeAg alone. Co-existing liver disease occurred in 18 (25.7%); hypocomplementaemia (low C3 and C4) in 22 (47.8%) and 5 (10.9%) of these 46 children respectively. Sixty-five (92.9%) of the 70 patients had normal renal function; 1(1.4%) impaired renal function; 3 (4.3%) chronic renal insufficiency and 1(1.4%) end stage renal disease at last hospital visit. Twelve (17.1%) of the 70 patients were in remission; all having cleared HBeAg. HBVMN was clinically indistinguishable from 24 children with idiopathic MN although biochemical characteristics were different. There were 23 patients with histological lesions other than MN. Forty patients with clinical, biochemical and serological findings similar to those with HBVMN and the other histological types, were unbiopsied. This report delineates the natural history of HBV infection in black South African children with NS, the majority of whom have MN. Disease remission in HBVMN parallels elimination of HBV antigens, particularly HBeAg. Comparison of HBVMN with idiopathic MN revealed clinically indistinguishable characteristics but unexplained biochemical differences [14]. Little is understood of the biosocial context in which HBV-associated nephropathy (particularly MN) develops. In the next two studies we evaluated HBV status and proteinuria in family members and household contacts of index children with HBVMN to test the hypothesis that HBV carriage and asymptomatic proteinuria are closely linked and may be causally associated. In the first of these two studies, thirty-one black children with biopsy-proven HBVMN were the index cases. One hundred and fifty-two family members and 43 black household contacts were the subjects of this study. We assessed HBV carrier status by testing for HBV antigens and antibodies using enzyme-linked immunosorbent assays (ELISA) and for HBV DNA by using slot-blot hybridisation and nested polymerase chain reaction. Sequencing of the precore HBV region of HBV was done in a subset of both index cases and subjects. Proteinuria was assessed by measuring the urinary protein: creatinine ratio. Seventy-two (37%) of the 197 family members and household contacts were HBV carriers, and 53 (27%) had a protein: creatinine ratio greater than the physiological limit (protein: creatinine ratio <0.2). Abnormal proteinuria was defined by a protein: creatinine ratio 0.2. Continuous data was compared using analysis of variance. Categorical data were compared using Chi-square test or Fisher’s exact test where appropriate. A probability of <0.05 was considered significant. The frequency of abnormal proteinuria was not significantly different in those with [22 (30.5%) of 72] or without [33 (32%) of 104] HBV carriage. This lack of association remained when carriers were classified into those who were HBsAg positive only and those with active viral replication (HBsAg and/or HBeAg and/or HBV DNA; p = 0.01). Family members were more predisposed to HBV carriage than household contacts, but abnormal proteinuria was present with equal frequency (p = 0.48). Age had a significant impact on proteinuria, with children less than five years being more likely to have abnormal proteinuria (p = 0.008). The prevalence of abnormal proteinuria in family members and household contacts of the index cases was more than in community-based controls. The 10 index HBVMN cases and 14 family members and household contacts that were tested all had HBV of genotype A. The results suggest that the family members and household contacts of children with HBVMN are at very high risk of HBV carriage; they also have asymptomatic proteinuria at a significantly higher rate than community-based controls. The HBV carrier status was not associated with proteinuria. This lack of association was a finding supported by peak prevalences of proteinuria in those under five years but no corresponding peak of HBV carriage. Proteinuria may indicate glomerular basement membrane dysfunction. Environmental and social factors may underpin development of these two disorders, but are insufficient to account for the index cases of HBVMN. The emergence of children with HBVMN from such households additionally depends on unidentified and possibly genetic factors [17]. In the second study of the biosocial background in which the HBV carrier-state with MN develops, we used the same subjects. One hundred and twenty-three unrelated individuals from the communities of the index cases, negative for HBV, served as controls. In this study, proteinuria was assessed using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and protein: creatinine ratios. Patterns of proteinuria on SDS-PAGE were classified as glomerular, tubular or mixed; IgG and haptoglobulin were suggestive of MN. Seventy-two (36.9%) of the 195 family members and household contacts were HBV carriers; 21 (29.2%) of these carriers had evidence of proteinuria using SDS-PAGE. Twenty-eight (41.2%) of the sixty-eight members of the study group who were HBV negative and 26.8% of the controls also showed proteinuria on SDS-PAGE. This lack of association between HBV carriage and proteinuria remained when controlled for gender and family relationship. Also, HBV was not protective against the development of proteinuria. Age was associated directly with a glomerular pattern of proteinuria (p = 0.007). Those having a pattern of proteinuria suggestive of MN were more likely to have an abnormal protein: creatinine ratio (p = 0.001). Ten (59%) subjects with a membranous pattern of proteinuria and 19 (47.5%) with a non-membranous pattern of proteinuria had microscopic haematuria. Such a pattern of proteinuria was not significantly different between subjects and community based controls (8.7% vs. 6.5%, p = 0.5). Environmental exposures in these subjects may be responsible for the proteinuria, which probably reflects underlying glomerular basement membrane damage. Discordance between the HBV carrier-state and patterns of proteinuria in the study group suggest that interaction between specifically vulnerable individuals and HBV group suggest HBV and MN may not be causally related or that it reflects exceptional interaction between specifically vulnerable individuals and HBV [18]. From the above two studies we inferred that the pathogenetic mechanisms by which individuals with chronic HBV infection develop MN are probably dependent on interactions between viral, host and environmental factors; some evidence suggests a genetic predisposition. We therefore undertook another two studies to explore HLA associations in black children with HBVMN. In the first of these two studies, thirty black children, age range 2 to 16 years, with biospy-proven HBVMN, were the subjects of this study. HLA A, B and C antigens were determined using a two-stage lymphocytotoxic test. HLA DRB1* and DQB1* typing was done using sequence-specific primers. HLA class I and II antigen frequencies of the study subjects were compared to controls that were randomly chosen healthy blood donors from the same population. HLA DQB1*0603 was increased in patients with HBVMN compared to controls (chi-square 13.65, RR 4.3). DRB1*07 and DQB1*02 were increased in frequency in the study subjects but failed to reach statistical significance. There was no significant difference in the frequencies of class I antigens in the study group compared to controls. This study is the first report of HLA associations in black patients with HBVMN in whom Class I and II antigens were determined using molecular methodology. It shows a high frequency of DQB1*0603 in black children with HBVMN compared to controls suggesting a possible genetic predisposition to the development of HBVMN [19]. Following our findings of an HLA Class II association in black children with HBVMN, we proceeded to determine if HLA DQB1*0603 predisposes to HBV carriage and development of abnormal proteinuria in the second study. We studied 70 family members of 14 children with HBVMN positive for HLA DQB1*0603 selected from the first study. Associations of HLA DQB1*0603 to HBV carriage and abnormal proteinuria were determined using the mean probability ratio (LOD scores). Forty-seven of the 70 (67%) family members were positive for HBV infection. Nineteen (27%) had abnormal range proteinuria. LOD scores in the study subjects with DQB1*0603 who were HBV negative vs. those with DQB1*0603 who were HBV positive was not significant (anti-log sum = 2.0559 and average 0.23). When a similar calculation was done for abnormal proteinuria, there were no significant findings (anti-log sum = 3.8587 and average 0.43). This lack of association between HLA DQB1*0603 with either HBV carriage or abnormal proteinuria in family members suggests that additional factors may play a role in predisposing children to chronic HBV carriage and the development of MN. We therefore conclude that the main effect of HLA DQB1*0603 which distinguishes HBVMN from family members is the degree of proteinuria which is a reflection of the severity of glomerular basement membrane damage in the latter [20]. In the next study we proceed to investigate the efficacy of Interferon alpha 2b (INTRON A ®) in the treatment of HBV-associated nephropathy in black children. Twenty-four black children with biopsy-proven HBV-associated nephropathy were recruited into the study during the period April 1997 to June 1999. Five defaulted treatment and were excluded from the primary analysis. IFN 2b was administered for 16 weeks. Response to treatment was defined as loss of HBeAg, decrease in proteinuria, and prevention of deterioration in renal and liver function. A control group of 20 patients was followed up for the same period. Ten (52.6%) of the treated children responded with clearance of HBeAg by 40 weeks. None cleared HBsAg. All responders showed remission of proteinuria, 90% maintained normal renal function and 1 (10%) showed improvement of renal function. HBV DNA levels decreased in this group. Nine patients did not clear HBeAg; none showed remission of proteinuria, 2 showed deterioration of renal function. Liver enzymes rose during treatment but subsequently declined irrespective of response to therapy. No serious side effects were encountered. Only 5% of controls showed spontaneous clearance of HBeAg, and none had remission of proteinuria. Black children with HBV-associated nephropathy show accelerated clearance of HBeAg with remission of proteinuria following treatment with IFN 2b. IFN 2b was well-tolerated [21]. We then went on to investigate the impact of HBV vaccination in South Africa over 6 years on HBV-associated MN. HBV vaccine has resulted in a decline in the incidence of HBV carriage and hepatocellular carcinoma in South East Asia. Vaccine efficacy in Africa has not been adequately assessed. King Edward VIII Hospital, Durban, South Africa, is the only tertiary referral centre for the province of KwaZulu/Natal for children with renal diseases. HBV vaccine was introduced into the Extended Programme on Immunisation (EPI) in April 1995; vaccine coverage rates between 1995-2001 for children for the first, second and third doses were 85.4%, 78.2% and 62.0% respectively. HBV status was determined using radioimmunoassay (1984 – 1991) or ELISA. MN was confirmed on renal biopsy. The hospital average annual incidence of HBVMN was compared pre and post-vaccination, and according to age groups. Between 1984 and 2001 there were 119 children with HBVMN; the mean age was 7 years (range 1 to 14 years) and 101(85%) were males. The average annual rate ratio (aRR) per 105 child population was 0.25. The aRR of 0.03 for the years 2000-2001, was significantly lower than the aRR of 0.22 during the pre-immunisation period (1984 – 1994) [p = 0.003; RR = 0.12 (95% CI: 0.03 – 0.5)]. The aRR in 2000-2001 for children 0 – 4 years (0.00) and 5 – 10 years (0.09) were significantly lower than in the pre-vaccination years (0.16 and 0.46, p = 0.01 and 0.02 respectively). Thus, HBV vaccine, even at low coverage for the full EPI schedule, reduced the hospital incidence of HBVMN by six years [22]. From this series of studies we concluded that prior to the introduction of the HBV vaccine into the Expanded Programme on Immunisation in Children, HBV-associated nephropathy, particularly MN was the commonest form of NS in black children. Several studies have suggested on the basis of epidemiological, clinical and immunological evidence a causal association between chronic HBV carriage and the development of nephropathy. In our present series of studies we have findings that lend further support to the causal association between HBV carriage and development of nephropathy, particularly MN, in black children. We have shown that genetic and other environmental factors may also play a role in determining the degree of proteinuria. Those children with abnormal range proteinuria less than the nephrotic range show no association with HBV carriage or genetic factors with regard to HLA linkage. The efficacy of interferon treatment in elimination of the HBV and abrogation of proteinuria following clearance of the virus (particularly the HBeAg) as well as the impact of routine HBV immunisation in preventing HBV carriage and subsequent development of nephropathy lends further support to our findings. The impact of viral load has yet to be investigated. / Thesis (Ph.D.)-University of Natal, Durban, 2002.

Thesis (Ph.D.)--University of Tennessee Health Science Center, 2006. / Title from title page screen (viewed on October 26, 2007 ). Research advisor: Mona Newsome Wicks, Ph.D., RN. Document formatted into pages (xii, 174 p. : ill.) Vita. Abstract. Includes bibliographical references (p. 115-132).

Made available in DSpace on 2015-07-22T20:50:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-29 / Nesse estudo objetivou-se realizar a tradução para o português e a adaptação cultural do instrumento Chronic Liver Disease Questionnaire (CLDQ) para uso no Brasil. O instrumento foi traduzido da versão original (Inglês) para a língua portuguesa pelos autores e, posteriormente, revisado e avaliado quanto ao grau de dificuldade das traduções e equivalência por tradutores bilíngües. O instrumento foi, então, aplicado em 20 pacientes com hepatopatia crônica selecionados aleatoriamente. Não houve dificuldade na compreensão do instrumento, todas as questões foram consideradas aplicáveis pelos pacientes, e a equivalência cultural do CLDQ foi demonstrada sem que mudanças na tradução original precisassem ser feitas. A tradução e a adaptação cultural do CLDQ para o português, no Brasil, foram realizadas, tendo sido cumprida esta importante etapa para sua validação e utilização em nosso meio. / The aim of this study was to carry out the translation from English into Portuguese and the transcultural adaptation of the Chronic Liver Disease Questionnaire to use in Brazil. The instrument was translated from the original version (English) into Portuguese language by the authors and then, it was revised. The degree of difficulty of the translations and equivalence for bilingual translators were evaluated. The instrument was, then, applied in 20 patients with chronic liver disease randomly selected. It was easy to the patients understand the instrument, all the questions had been considered applicable by the patients, and the cultural equivalence of the CLDQ was demonstrated without changes in the original translation. The translation and the transcultural adaptation of CLDQ into Portuguese, in Brazil, had been carried out, having been fulfilled to this important stage for its validation and use in our way. / TEDE / BV UNIFESP: Teses e dissertações

INTRODUÇÃO: O transplante hepático (TxH) vem mudando o curso de doenças graves, incapacitantes e potencialmente fatais, se tornando o tratamento de escolha quando há falência do órgão. OBJETIVO: Comparar as taxas de TxH, exclusão e sobrevida entre candidatos com cirrose descompensada (CIR), situações especiais (SPE) e carcinoma hepatocelular (HCC). MÉTODOS:Foram realizados dois estudos em 358 pacientes: uma coorte retrospectiva (agosto de 2008 - julho de 2009, incluindo 189 pacientes listados) e uma prospectiva (de novembro de 2012 a maio de 2014, com um período de acompanhamento até novembro de 2015, incluindo 169 candidatos a transplante hepático, comparando CIR, HCC e SPE. Foram avaliadas as seguintes variáveis: K-in (taxas de entrada da lista de espera: K-1in se CIR, K-2in se HCC e K-3in se SPE); K-out (taxa de TxH); K-1out (drop out no grupo CIR); K-2out (drop out no grupo HCC) e K-3out(drop out no grupo SPE). RESULTADOS: Na coorte retrospectiva, 112 casos (59,3%) tinham CIR, 63 (33,3%) com HCC e 14 (7,4%) se enquadraram em SPE. Os tempos médios de avaliação até a inscrição em lista para TxH foram 194 dias (IC 95% 152-236), 36 dias (IC95% 21-50) e 98 dias (IC95% 0-308) para CIR, HCC e SPE, respectivamente (P <0,001). Dos 86 pacientes transplantados (K-out = 45,5%), 31 tinham CIR (K-1in = 27,7%), 44 HCC (K-2in = 69,8%) e 11 SPE (K-3in = 88,6%) (P <0,001). As taxas de drop out foram maiores em CIR (K-1out = 64,3%, K-2out = 30,2%, K-3out = 21,4%, P <0,001). O hazar ratio (HR) para TxH foi 85% (IC95% 1,35-2,55) maior em HCC do que CIR. Na coorte prospectiva, 110 dos 167 pacientes avaliados foram listados (K-in = 65,9%). Os tempos médios de avaliação foram de 783 dias (IC95% 330-1236), 52 dias (IC95% 17-87) e 184 dias (IC95% 19-349) para CIR, HCC e SPE, respectivamente (P <0,001). Em relação ao TxH, o K1-in foi 21,7%, K2-in, 76,4% e K3-in, 92,3 % (P <0,001). K-out foi 57,3% (63/110), K1-out = 50%, K2-out = 21,1% e K3-out = 3,84% (P <0,001). HR para TxH foi 329% superior em HCC do que CIR (HR = 4,29; IC95%: 2,74-6,72). CONCLUSÃO: Neste estudo, os pacientes com cirrose descompensada tiveram um tempo de avaliação para transplante significativamente maior que os outros grupos avaliados, bem como maior taxa de drop out em lista. A taxa de transplante foi significativamente menor nos pacientes com cirrose descompensada, demonstrando que as políticas de alocação de órgãos merecem ser revistas. / INTRODUCTION: Liver transplantation (LT) has been changing the course of serious, incapacitating and potentially fatal diseases becoming the treatment of choice when there is organ failure. AIM: To compare transplant, delisting, and survival rates between candidates with decompensated cirrhosis (CIR), special conditions (SPE), and hepatocellular carcinoma (HCC). METHODS: We carried out two studies with 358 patientes: a retrospective one (Aug 2008-Jul 2009, including 189 enlisted patients) and another prospective (Nov 2012-May 2014, with a follow-up period up to Nov 2015, including 169 LT candidates), comparing CIR, HCC, and SPE. The following variables were assessed: K-in (rates of waitlist entry – K-1in if CIR, K-2in if HCC, and K-3in if SPE); K-out (rate of LT); K-1out (drop-out in CIR); K-2out (drop-out in HCC); and K-3 out (drop-out in SPE). RESULTS: In the retrospective study, 112 cases (59.3%) were due to CIR, 63 (33.3%) to HCC, and 14 (7.4%) to SPE. The average time from selection to enlisting was 194 days (CI95% 152-236), 36 days (CI95% 21-50), and 98 days (CI95% 0-308) for CIR, HCC, and SPE, respectively (P<0.001). Of the 86 transplanted patients (K-out = 45.5%), 31 had CIR (K-1in = 27.7%), 44 HCC (K-2in = 69.8%), and 11 SPE (K-3in = 88.6%) (P<0.001). Drop-out rates were higher in CIR (K-1out = 64.3%, K-2out = 30.2%, K-3out = 21.4%, P<0.001). The hazar ratio (HR) for LT was 85% (CI95% 1.35-2.55) higher in HCC than CIR. In the prospective study, 110 out of 167 evaluated patients were enlisted (K-in = 65.9%). The average time from selection to enlisting was 783 days (CI95% 330-1236), 52 days (CI95% 17-87), and 184 days (CI95% 19-349) for CIR, HCC, and SPE, respectively (P<0.001). Regarding LT, K1-in was 21.7%, K2-in, 76.4%, and K3-in, 92.3% (P<0.001). K-out was 57.3% (63/110), K1-out = 50%, K2-out = 21.1%, and K3-out = 3.84% (P<0.001). HR for LT was 329% times higher in HCC than CIR (HR = 4.29; CI95% 2.74–6.72).CONCLUSION: In this study, patients with decompensated cirrhosis had a time evaluation for transplantation significantly higher than other evaluated groups as well as a higher rate of waiting list drop out. Transplant rate was significantly lower in patients with decompensated cirrhosis, demonstrating that organ allocation policies deserve to be reviewed.

INTRODUÇÃO: O transplante hepático (TxH) vem mudando o curso de doenças graves, incapacitantes e potencialmente fatais, se tornando o tratamento de escolha quando há falência do órgão. OBJETIVO: Comparar as taxas de TxH, exclusão e sobrevida entre candidatos com cirrose descompensada (CIR), situações especiais (SPE) e carcinoma hepatocelular (HCC). MÉTODOS:Foram realizados dois estudos em 358 pacientes: uma coorte retrospectiva (agosto de 2008 - julho de 2009, incluindo 189 pacientes listados) e uma prospectiva (de novembro de 2012 a maio de 2014, com um período de acompanhamento até novembro de 2015, incluindo 169 candidatos a transplante hepático, comparando CIR, HCC e SPE. Foram avaliadas as seguintes variáveis: K-in (taxas de entrada da lista de espera: K-1in se CIR, K-2in se HCC e K-3in se SPE); K-out (taxa de TxH); K-1out (drop out no grupo CIR); K-2out (drop out no grupo HCC) e K-3out(drop out no grupo SPE). RESULTADOS: Na coorte retrospectiva, 112 casos (59,3%) tinham CIR, 63 (33,3%) com HCC e 14 (7,4%) se enquadraram em SPE. Os tempos médios de avaliação até a inscrição em lista para TxH foram 194 dias (IC 95% 152-236), 36 dias (IC95% 21-50) e 98 dias (IC95% 0-308) para CIR, HCC e SPE, respectivamente (P <0,001). Dos 86 pacientes transplantados (K-out = 45,5%), 31 tinham CIR (K-1in = 27,7%), 44 HCC (K-2in = 69,8%) e 11 SPE (K-3in = 88,6%) (P <0,001). As taxas de drop out foram maiores em CIR (K-1out = 64,3%, K-2out = 30,2%, K-3out = 21,4%, P <0,001). O hazar ratio (HR) para TxH foi 85% (IC95% 1,35-2,55) maior em HCC do que CIR. Na coorte prospectiva, 110 dos 167 pacientes avaliados foram listados (K-in = 65,9%). Os tempos médios de avaliação foram de 783 dias (IC95% 330-1236), 52 dias (IC95% 17-87) e 184 dias (IC95% 19-349) para CIR, HCC e SPE, respectivamente (P <0,001). Em relação ao TxH, o K1-in foi 21,7%, K2-in, 76,4% e K3-in, 92,3 % (P <0,001). K-out foi 57,3% (63/110), K1-out = 50%, K2-out = 21,1% e K3-out = 3,84% (P <0,001). HR para TxH foi 329% superior em HCC do que CIR (HR = 4,29; IC95%: 2,74-6,72). CONCLUSÃO: Neste estudo, os pacientes com cirrose descompensada tiveram um tempo de avaliação para transplante significativamente maior que os outros grupos avaliados, bem como maior taxa de drop out em lista. A taxa de transplante foi significativamente menor nos pacientes com cirrose descompensada, demonstrando que as políticas de alocação de órgãos merecem ser revistas. / INTRODUCTION: Liver transplantation (LT) has been changing the course of serious, incapacitating and potentially fatal diseases becoming the treatment of choice when there is organ failure. AIM: To compare transplant, delisting, and survival rates between candidates with decompensated cirrhosis (CIR), special conditions (SPE), and hepatocellular carcinoma (HCC). METHODS: We carried out two studies with 358 patientes: a retrospective one (Aug 2008-Jul 2009, including 189 enlisted patients) and another prospective (Nov 2012-May 2014, with a follow-up period up to Nov 2015, including 169 LT candidates), comparing CIR, HCC, and SPE. The following variables were assessed: K-in (rates of waitlist entry – K-1in if CIR, K-2in if HCC, and K-3in if SPE); K-out (rate of LT); K-1out (drop-out in CIR); K-2out (drop-out in HCC); and K-3 out (drop-out in SPE). RESULTS: In the retrospective study, 112 cases (59.3%) were due to CIR, 63 (33.3%) to HCC, and 14 (7.4%) to SPE. The average time from selection to enlisting was 194 days (CI95% 152-236), 36 days (CI95% 21-50), and 98 days (CI95% 0-308) for CIR, HCC, and SPE, respectively (P<0.001). Of the 86 transplanted patients (K-out = 45.5%), 31 had CIR (K-1in = 27.7%), 44 HCC (K-2in = 69.8%), and 11 SPE (K-3in = 88.6%) (P<0.001). Drop-out rates were higher in CIR (K-1out = 64.3%, K-2out = 30.2%, K-3out = 21.4%, P<0.001). The hazar ratio (HR) for LT was 85% (CI95% 1.35-2.55) higher in HCC than CIR. In the prospective study, 110 out of 167 evaluated patients were enlisted (K-in = 65.9%). The average time from selection to enlisting was 783 days (CI95% 330-1236), 52 days (CI95% 17-87), and 184 days (CI95% 19-349) for CIR, HCC, and SPE, respectively (P<0.001). Regarding LT, K1-in was 21.7%, K2-in, 76.4%, and K3-in, 92.3% (P<0.001). K-out was 57.3% (63/110), K1-out = 50%, K2-out = 21.1%, and K3-out = 3.84% (P<0.001). HR for LT was 329% times higher in HCC than CIR (HR = 4.29; CI95% 2.74–6.72).CONCLUSION: In this study, patients with decompensated cirrhosis had a time evaluation for transplantation significantly higher than other evaluated groups as well as a higher rate of waiting list drop out. Transplant rate was significantly lower in patients with decompensated cirrhosis, demonstrating that organ allocation policies deserve to be reviewed.

INTRODUÇÃO: A recidiva de varizes é frequente após tratamento endoscópico com ligadura elástica para a profilaxia secundária de hemorragia por rotura de varizes esofágicas em pacientes com doença hepática crônica avançada. Alguns estudos relacionaram tanto recidiva quanto ressangramento de varizes com características ecoendoscópicas de vasos paraesofágicos. OBJETIVO: Relacionar avaliações ecoendoscópicas de varizes paraesofágicas, veia ázigos e ducto torácico com recidiva de varizes após erradicação com ligadura elástica em pacientes com doença hepática crônica avançada através de estudo prospectivo e observacional. MÉTODOS: A análise ecoendoscópica foi realizada antes da terapia com ligadura elástica e 1 mês após a erradicação endoscópica das varizes. Os diâmetros máximos das varizes paraesofágicas, da veia ázigos e do ducto torácico foram avaliados em localizações ecoendoscópicas prédeterminadas. Após a erradicação das varizes, os pacientes foram submetidos a endoscopias a cada 3 meses durante o período de 1 ano. Foi verificado se alguma das características ecoendoscópicas analisadas poderia predizer a recidiva das varizes. RESULTADOS: Um total de 30 pacientes completou o protocolo de seguimento por 1 ano. Dezessete (57%) pacientes apresentaram recidiva de varizes. Não houve relação entre os diâmetros máximos da veia ázigos e do ducto torácico com a recidiva de varizes. O diâmetro máximo de varizes paraesofágicas foi fator preditivo para recidiva de varizes em ambos os períodos avaliados. Os diâmetros das varizes paraesofágicas que melhor se relacionaram com recidiva de varizes foram 6,3 mm antes da ligadura elástica (sensibilidade de 52,9%, especificidade de 92,3% e área sob a curva ROC de 0,749) e 4 mm após a ligadura elástica (70,6% de sensibilidade, 84,6% de especificidade e área sob a curva ROC de 0,801). CONCLUSÃO: A medida ecoendoscópica do diâmetro das varizes paraesofágicas pode predizer a recidiva das varizes esofágicas no primeiro ano após a erradicação com ligadura elástica. O diâmetro de varizes paraesofágicas após a ligadura elástica é o melhor fator preditivo, pois apresenta menor valor de corte, maior sensibilidade e maior área sob a curva ROC / INTRODUCTION: Variceal recurrence after endoscopic band ligation for secondary prophylaxis is a frequent event. Some studies have reported a correlation between variceal recurrence and variceal re-bleeding with the endoscopic ultrasound (EUS) features of para-esophageal vessels. OBJECTIVE: A prospective observational study was conducted to correlate EUS evaluation of para-esophageal varices, azygos vein and thoracic duct with variceal recurrence after endoscopic band ligation variceal eradication in patients with in advanced chronic hepatic disease. METHODS: EUS was performed before and 1 month after endoscopic band ligation variceal eradication. Para-esophageal varices, azygos vein and thoracic duct maximum diameters were evaluated in pre-determined anatomic stations. After endoscopic band ligation variceal eradication, patients were submitted to endoscopic examinations every 3 months for 1 year. We looked for EUS features that could predict variceal recurrence. RESULTS: A total of 30 patients completed 1-year endoscopic follow-up. Seventeen (57%) patients presented variceal recurrence. There was no correlation between azygos vein and thoracic duct diameters with variceal recurrence. The maximum diameter of para-esophageal varices predicted variceal recurrence in both evaluation periods. Para-esophageal varices diameters that best correlated with variceal recurrence were 6.3 mm before endoscopic band ligation (52.9% sensitivity, 92.3% specificity, and 0.749 area under ROC curve); and 4 mm after endoscopic band ligation (70.6% sensitivity, 84.6% specificity, and 0.801 area under ROC curve). CONCLUSION: We conclude that paraesophageal varices diameter measured by EUS predicts variceal recurrence within one year after endoscopic band ligation variceal eradication. Paraesophageal diameter after variceal eradication is a better recurrence predictor, because it has lower cut-off parameter, higher sensitivity and higher area under the ROC curve

L’infection par le virus de l’hépatite B (VHB) reste un problème majeur de santé publique. L’infection chronique par le VHB peut conduire au développement d’une cirrhose et d’un carcinome hépatocellulaire (CHC). L’ARN pré-génomique du VHB (ARNpg), matrice de la réplication virale, peut aussi subir un épissage alternatif dans les hépatocytes. L’ARN simple-épissé SP1 (ARNSP1) est le variant majeur détecté. L’ARNSP1 génère des particules virales défectives (VHBd) et code la protéine HBSP (HBV splicing-generated protein). Des études récentes ont démontré que la proportion de VHBd dans le sérum augmente lors de la progression de maladies hépatiques et précède le développement de CHC. Notre équipe ainsi que d’autres ont décrit qu’HBSP pouvait pirater les voies de signalisation intervenant dans l’immunité innée et limiter l’étendue de l’inflammation du foie. Le but de notre étude est de comprendre la régulation de l’épissage alternatif viral et cellulaire au cours de la pathogenèse hépatique. Nous avons montré:1) une diminution du recrutement immunitaire et une réduction de la fibrose hépatique les souris exprimant HBSP régulée par épissage alternatif. 2) dans 6 modèles murins différents une régulation de l’expression des facteurs épissage variable selon la maladie du foie et définissant une signature spécifique. Cette régulation de facteurs d’épissage et de l’épissage alternatif a été observée dans les CHC de patients. En conclusion, nos résultats soulignent l’impact de l’atteinte hépatique sur l’expression des facteurs d’épissage, lesquels pourraient contribuer à réguler à la fois l’épissage viral et cellulaire et par conséquent, la progression de la pathogenèse hépatique. / Hepatitis B virus (HBV) infection remains a major public health problem with 250 million chronic carriers worldwide. Chronic HBV infection may lead to the development of cirrhosis and hepatocellular carcinoma (HCC). HBV pregenomic RNA (pgRNA), matrix of viral replication, could also undergo alternative splicing (AS) in hepatocytes. The singly spliced SP1RNA is the major HBV spliced variant detected. SP1RNA generates defective viral particles (dHBV) and encodes for HBV splicing-generated protein (HBSP). Recent studies found the proportion of serum dHBV increased during the progression of liver disease and prior to development of HCC. In addition, our group and others revealed that HBSP hacked signaling pathways involved in innate immunity and limit the extent of liver inflammation. The aim of our study was to investigate the regulation of viral and cellular alternative splicing in the pathogenesis of liver diseases. Our data showed that 1) the modulated expression of splicing factors in HBV transgenic mice contributed to an increase of SP1RNA encoding for HBSP. In HBSP transgenic mice, HBSP expression led to the decrease of inflammatory mono/macrophages recruitment and consequently impaired liver fibrogenesis. 2) the pattern of selected splicing factors expression varied according to liver disease in mouse models, and overexpression of splicing factors and enhanced alternative splicing of target genes were observed in HCC tumors. In conclusion, our data highlighted the impact of liver diseases on the expression of splicing factors which may contribute to regulate both viral and cellular splicing events and consequently the progression of liver pathogenesis.

L’hétérogénéité de l’histoire naturelle de l’hépatite C est expliquée par l’existence de facteurs environnementaux ou liés au malade qui influencent l’évolution de la maladie. L’obtention d’une réponse virologique soutenue est l’objectif principal de la prise en charge thérapeutique car c’est la seule façon de réduire l’incidence de la cirrhose et la mortalité liée au virus de l’hépatite C. Pour être efficaces, les stratégies thérapeutiques doivent être élaborées à deux niveaux. A l’échelle individuelle, elles doivent optimaliser les chances de réponse virologique tout en limitant l’exposition aux effets secondaires. A l’échelle d’une population, la meilleure stratégie est celle qui aura l’impact le plus important sur l’incidence de la cirrhose et sur la mortalité liées au virus de l’hépatite C.<p>Les travaux réalisés dans le cadre de cette thèse ont permis d’identifier des critères virologiques autorisant l’arrêt d’un traitement inefficace dès le terme de la 4ème semaine chez les malades présentant des transaminases normales et chez les malades non répondeurs à un premier traitement, de quantifier la perte de chance de réponse virologique lorsque la durée du traitement est limitée à 24 semaines chez les malades infectés par un génotype 1, d’évaluer la place de l’amantadine dans l’arsenal thérapeutique, de quantifier l’impact d’une insulino-résistance sur le taux de réponse virologique, de contribuer à l’élaboration d’une stratégie thérapeutique permettant une meilleure tolérance hématologique chez les malades hémodialysés et de quantifier l’impact des polymorphismes de l’interleukine 28B sur le taux réponse virologique des malades infectés par un génotype 2 ou 3. Nos travaux ont également permis de mesurer l’impact d’une consommation excessive d’alcool sur la morbi-mortalité liée au virus de l’hépatite C à l’échelle d’une population et de quantifier l’impact des mesures thérapeutiques actuelles et de stratégies thérapeutiques alternatives sur cette morbi-mortalité. <p>Au cours de la prochaine décennie, le traitement de l’hépatite chronique C sera articulé autour des molécules antivirales spécifiques agissant directement contre le virus de l’hépatite C. De nouvelles stratégies thérapeutiques intégrant la cinétique virale et les marqueurs génétiques prédictifs de la réponse virologique soutenue devront être élaborées afin d’offrir les meilleures chances d’éradication virologique au plus grand nombre de malades. / Doctorat en sciences médicales / info:eu-repo/semantics/nonPublished

La modélisation de maladies métaboliques hépatiques et les approches de thérapie cellulaire nécessitent de disposer d’une source fiable et illimitée d’hépatocytes. Grâce à leurs propriétés spécifiques, les cellules souches pluripotentes peuvent représenter une telle source. Nous avons tout d’abord mis au point une approche originale pour différencier une lignée de cellules souches embryonnaires humaines européenne, générée en conditions GMP-compatibles, en hépatocytes fonctionnels in vitro et in vivo après transplantation dans un modèle murin d'insuffisance hépatique aiguë. Nous avons ensuite utilisé les cellules souches pluripotentes induites (iPSC) spécifiques d’un patient homozygote pour une mutation entrainant une absence de récepteur des lipoprotéines de basse densité (RLDL) afin de modéliser l'hypercholestérolémie familiale (HF) in vitro. Nous avons amélioré notre approche pour différencier ces iPSC en hépatocytes plus matures et polarisés car les hépatocytes sont les seules cellules capables de dégrader le cholestérol via la bile. Nous avons montré que ce modèle reproduit la physiopathologie de l'HF et établit la preuve de concept de la correction génétique ciblée par la technologie CRISPR/Cas au locus AAVS1 par la restauration de l’expression, inductible par les statines, et de la fonctionnalité du récepteur. Nous avons également mis en évidence que le RLDL ne semble pas impliqué dans l'entrée du virus de l'hépatite C (VHC) mais plutôt dans les étapes tardives de la morphogénèse virale. Ce modèle pourra désormais servir à l’étude physiopathologique de différents patients HF, au criblage de nouvelles drogues hypocholestérolémiantes et antivirales ainsi qu'à de nouvelles approches thérapeutiques. / Liver metabolic diseases modeling and cell therapy approaches require a a reliable and well-characterized cell source. Due to their specific properties, pluripotent stem cells represent a credible alternative to primary human hepatocytes. Thus, we have defined a new approach to differentiate a European human embryonic stem cell line, generated in GMP-compatible conditions, into hepatocytes that are functional in vitro and in vivo after transplantation into a murine model of acute liver failure. We have then used induced pluripotent stem cells from a homozygous patient with a mutation leading to an absence of the low-density lipoproteins receptor (LDLR) to model familial hypercholesterolemia type IIA (FH) in vitro. As hepatocytes are the only cells able to metabolize cholesterol into bile acids, we have improved our approach to differentiate these iPSC into hepatocytes displaying cell functional organization and polarization. We have shown that our model reproduced FH physiopathology and have also restored, by the genetic targeted correction at the AAVS1 locus using CRISPR/Cas technology and subsequent hepatocyte differentiation, the LDLR expression – inducible by statins - and functionality. Moreover, we have demonstrated that the LDLR does not seem to be involved in hepatitis C virus entry or replication but rather in viral morphogenesis steps. This model will be useful to develop new cholesterol-lowering and antiviral drugs as well as new cell therapy options. Furthermore, it can be applied to similar studies for other liver metabolic disorders.