Introdução: A atresia biliar (AB) inclui obstrução completas das vias biliares extra-hepáticas e uma colangiopatia intra-hepática progressiva, cirrogênica. A natureza da colangiopatia destes processos permanece obscura. Uma arteriopatia levando a colangiopatia isquêmica explicaria a natureza progressiva da lesão biliar. A imunolocalização do fator de crescimento endotelial vascular A (VEGFA) em ramos arteriais e ductos biliares intra-hepáticos e do porta hepatis dos pacientes com AB sugere isquemia nestas estruturas. A ocorrência de hipóxia hepatobiliar na AB necessita ser esclarecida. Objetivo: Determinar a presença de hipóxia nos fígados de pacientes com AB, analisando a expressão gênica dos fatores induzidos por hipóxia (HIF) -1α e -2α. Métodos: Estudo de amostras de biópsias em cunha coletadas na laparotomia exploradora de pacientes com AB isolada sem IgM+ para citomegalovírus (n= 32) comparando com lactentes com colestase intra-hepática (CIH, n= 09), pareados por idade. Uma amostra foi ultracongelada (análise molecular) e outra, parafinizada (análises histológica e imunoistoquímica). Por PCRq, usando sondas TaqMan®, avaliaram-se as expressões gênicas de: HIF1-α, HIF2-α, proteína quimiotática de monócitos 1 (MCP1) (marcador de fibrose biliar), citoqueratina 19 (CK19) (marcador de colangiócitos). O gene normalizador foi 18S ribossômico. Por morfometria, foram quantificadas as extensões de fibrose e reação ductular. Dados clínico-laboratoriais foram prospectivamente coletados. Resultados: O grupo AB, comparado à CIH, apresentou maior expressão de HIF1-α e HIF2-α. No grupo AB, a expressão do HIF1-α correlacionou-se positivamente com a bilirrubina total (BT) sérica. Dois subgrupos de AB foram detectados quanto à expressão dos HIFs: alta (hiHIF, expressão 3x maior que a mediana da CIH) e baixa (loHIF). Pacientes hiHIF-1α eram mais velhos e com maiores níveis de BT e bilirrubina direta (BD) que loHIF-1α. O subgrupo hiHIF-2α apresentou expressão de CK19 inferior a do loHIF-2α. As demais variáveis foram semelhantes nos subgrupos HIFs. Conclusão: Na AB ocorre hipóxia tecidual hepática. Os dados sugerem a existência de hipóxia tecidual progressiva nos fígados afetados pela AB, associada ao desaparecimento de ductos biliares e à piora do quadro obstrutivo biliar. / Background: Biliary atresia (BA) includes a complete obstruction of the extrahepatic biliary tract and progressive intrahepatic cholangiopathy, and the nature of these processes remains unclear. An arteriopthy, leading to an ischemic cholangiopathy, can be involved. The immunolocalization of vascular endothelial growth factor A (VEGFA) in arterial branches and bile ducts both within the liver and at porta hepatis from patients with BA suggests ischemia in these structures. The occurrence of hypoxia in the hepatobiliary system in BA needs to be elucidated. Aim: To determinate the presence of hypoxia in the livers from patients with BA, by analyzing the gene expression of hypoxia-inducible factor (HIF) -1α and -2α. Methods: Liver biopsy specimens collected at exploratory laparotomy of age-matched patients with isolated, cytomegalovirus IgM-negative BA (n=32) and intrahepatic cholestasis (IHC, n=9) were evaluated. A sample was ultrafrozen (molecular analysis) and the other was paraffin-embedded (for histological and morphometric analyzes). Gene expression of: HIF-1α, HIF-2α, monocyte chemoattractant protein 1 (MCP1) (biliary fibrosis marker) and cytokeratin 19 (CK19) (cholangiocyte marker) were evaluated by PCRq using TaqMan® probes. The normalizing gene was 18S ribosomal. The extents of fibrosis and ductular reaction were assessed by morphometry. Clinical and laboratory data were prospectively collected. Results: There was higher HIF-1α and HIF-2α expression in BA in comparison with IHC. In BA, the HIF-1α expression was positively correlated with total serum bilirubin (TB). Two groups were observable in BA regarding HIFs: higher (hiHIF, considering as cutoff point a value higher than 3x the median of expression in IHC) and lower (loHIF). Patients with hiHIF-1α were older and presented increased levels of TB and direct-reacting serum bilirubin (DB) than loHIF-1α. Patients with hiHIF-2α presented CK19 expression lower than in loHIF-2α. The other variables were similar in subgroups HIFs. Conclusion: In BA there is hypoxia in the liver tissue, which seems to be progressive and associated with the disappearance of bile ducts and worsening biliary obstruction.

Introdução: As estenoses biliares são sempre desafiadoras, tanto no diagnóstico como na conduta terapêutica aplicada, seja ela curativa ou paliativa. A obtenção de espécimes se faz necessária uma vez que muitas doenças benignas mimetizam as neoplasias biliopancreáticas, tornando o diagnóstico anatomopatológico fundamental. Apesar da baixa acurácia, a colangiopancreatografia retrógrada endoscópica (CPRE) é o método tradicionalmente utilizado para diagnosticar estenoses biliares por meio do escovado citológico e da biópsia transpapilar. Por outro lado, diversos estudos têm reportado acurácia satisfatória da ecoendoscopia com punção aspirativa com agulha fina (EE-PAAF). Este estudo propõe comparar prospectivamente esses métodos no diagnóstico anatomopatológico da estenose biliar com suspeita de origem maligna. Métodos: Após a realização do cálculo amostral, 50 pacientes com estenoses biliares com suspeita maligna foram submetidos à CPRE com escovado citológico e biópsia transpapilar e à EE-PAAF durante a mesma sedação ou com intervalo máximo de sete dias. O padrão-ouro do resultado anatomopatológico dos métodos foram a cirurgia e o seguimento clínico por pelo menos seis meses. Foram avaliados os índices de acurácia (sensibilidade, especificidade, valor preditivo positivo e negativo, razão de verossimilhança positiva e negativa e acurácia), de concordância e as complicações entre os métodos, além da realização de subanálises, incluindo avaliação de técnicas, localização anatômica e tamanho da lesão. Resultados: O diagnóstico anatomopatológico obtido na associação dos dois métodos nos 50 pacientes (26 mulheres e 24 homens, com média de idade de 63,08 anos) foram: 47 malignos, um suspeito para malignidade e dois benignos. O diagnóstico definitivo definido pelo padrão-ouro demonstrou 48 estenoses malignas e duas benignas. O tamanho médio das lesões foi 3,48 cm, sendo 31 lesões extraductais e 19 intraductais, bem como 35 distais e 15 proximais. Na análise por intenção de tratamento, sensibilidade, especificidade e acurácia da EE foram superiores aos resultados da CPRE (93,8%, 100% e 94% contra 60,4%, 100% e 62%, respectivamente) (p = 0,034) com índices de complicações semelhantes. Não houve concordância entre os métodos e a combinação deles aumentou a sensibilidade e acurácia para 97,9% e 98%, respectivamente. Nas subanálises, a EE foi superior à CPRE tanto nas lesões extraductais com acurácia de 100% contra 54,8%, p=0,019, quanto nas lesões maiores que 1,5 cm (95,8% contra 61,9%, p=0,031). Entretanto os resultados foram semelhantes nas lesões intraductais e nas menores que 1,5 cm. Não houve diferença significativa entre os métodos nas análises de lesões proximais, distais e pancreáticas. Nas subanálises das técnicas empregadas, o escovado citológico e a biópsia transpapilar apresentaram resultados semelhantes entre si, tal como as técnicas de capilaridade e vácuo. Conclusão: A EE-PAAF é superior à CPRE associada ao escovado citológico e à biópsia transpapilar, com índices de complicações semelhantes. Não há concordância entre os métodos e a associação deles aumenta os índices de acurácia. A EE-PAAF é superior à CPRE com obtenção de espécimes na avaliação de lesões extraductais e nas maiores que 1,5 cm e é semelhante nas intraductais e nas menores que 1,5 cm. O escovado citológico e a biópsia transpapilar apresentam resultados semelhantes entre si, tal como as técnicas de capilaridade e vácuo. Não há diferença entre os métodos nas análises individuais de lesões distais, proximais e pancreáticas / Background and Aims: Biliary strictures are always a challenging clinical scenario and the anatomopathological diagnosis is essential in the therapeutic management, whether for curative or palliative purposes. The acquisition of specimens is necessary since many benign diseases mimic biliopancreatic neoplasms. Endoscopic retrograde cholangiopancreatography (ERCP) is the traditionally used method, despite its low accuracy based on biliary brush cytology and forceps biopsy. On the other hand, several studies reported good accuracy rates using endoscopic ultrasound guided-fine needle aspiration (EUS-FNA). The aim of this prospective study is to compare the accuracy of EUS and ERCP for tissue sampling of biliary strictures. Methods: After performing the sample calculation, fifty consecutive patients with indeterminate biliary strictures were included to undergo ERCP and EUS procedures on the same sedation or with a maximum interval of 7 days. The gold standard method was surgery or six months\' follow-up. Evaluation of the accuracy indices (sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio and accuracy), concordance and adverse events among the methods were performed. Also, subtype analyses of the techniques evaluation, anatomical localization and size of the lesion were included. Results: The final diagnosis reported in 50 patients (26 Female and 24 Male with a mean age of 63.08 years old) was 47 malignant, one suspicious for malignance and two benign lesions. Thirty-one lesions were extraductal and 19 intraductal, 35 were distal and 15 proximal strictures. The mean size of the lesion was 3.48 cm. In the intention-to-treat analysis, the sensibility and accuracy of EUS-FNA were superior than ERCP tissue sampling with biliary brush cytology and intraductal forceps biopsy (93.8%, 94% vs. 60.4%, 62%, respectively) (p=0.034), with similar adverse events. There was no concordance between the methods and combining both methods improved the sensitivity and accuracy for 97.9% and 98%, respectively. In the subtype analyses, the EUS-FNA was superior, with a higher accuracy than ERCP tissue sampling in evaluating extraductal lesions (100% vs. 54.8%, p=0.019) and in those larger than 1.5 cm (95.8% vs. 61.9%, p=0.031), but were similar in evaluating intraductal lesions and lesions smaller than 1.5 cm. There was no significant difference between the methods in the analyses of proximal, distal and pancreatic lesions. In the subtype analyses of the techniques employed, the brush cytology and the intraductal transpapillary biopsy presented similar results, as well as capillary and suction techniques. Conclusion: EUS-FNA is better than ERCP tissue sampling with biliary brush cytology and intraductal forceps biopsy with similar adverse events. There is no concordance between the methods and their association increases the accuracy. EUS-FNA is superior to ERCP tissue sampling in the assessment of extraductal lesions and in those larger than 1.5 cm and similar in the intraductal and in the lesions smaller than 1.5 cm. The brush cytology and intraductal transpapillary biopsy present similar results as well as capillary and suction techniques. There are no differences between methods in individual analyses of distal, proximal and pancreatic lesions

Introdução: A atresia biliar (AB) inclui obstrução completas das vias biliares extra-hepáticas e uma colangiopatia intra-hepática progressiva, cirrogênica. A natureza da colangiopatia destes processos permanece obscura. Uma arteriopatia levando a colangiopatia isquêmica explicaria a natureza progressiva da lesão biliar. A imunolocalização do fator de crescimento endotelial vascular A (VEGFA) em ramos arteriais e ductos biliares intra-hepáticos e do porta hepatis dos pacientes com AB sugere isquemia nestas estruturas. A ocorrência de hipóxia hepatobiliar na AB necessita ser esclarecida. Objetivo: Determinar a presença de hipóxia nos fígados de pacientes com AB, analisando a expressão gênica dos fatores induzidos por hipóxia (HIF) -1α e -2α. Métodos: Estudo de amostras de biópsias em cunha coletadas na laparotomia exploradora de pacientes com AB isolada sem IgM+ para citomegalovírus (n= 32) comparando com lactentes com colestase intra-hepática (CIH, n= 09), pareados por idade. Uma amostra foi ultracongelada (análise molecular) e outra, parafinizada (análises histológica e imunoistoquímica). Por PCRq, usando sondas TaqMan®, avaliaram-se as expressões gênicas de: HIF1-α, HIF2-α, proteína quimiotática de monócitos 1 (MCP1) (marcador de fibrose biliar), citoqueratina 19 (CK19) (marcador de colangiócitos). O gene normalizador foi 18S ribossômico. Por morfometria, foram quantificadas as extensões de fibrose e reação ductular. Dados clínico-laboratoriais foram prospectivamente coletados. Resultados: O grupo AB, comparado à CIH, apresentou maior expressão de HIF1-α e HIF2-α. No grupo AB, a expressão do HIF1-α correlacionou-se positivamente com a bilirrubina total (BT) sérica. Dois subgrupos de AB foram detectados quanto à expressão dos HIFs: alta (hiHIF, expressão 3x maior que a mediana da CIH) e baixa (loHIF). Pacientes hiHIF-1α eram mais velhos e com maiores níveis de BT e bilirrubina direta (BD) que loHIF-1α. O subgrupo hiHIF-2α apresentou expressão de CK19 inferior a do loHIF-2α. As demais variáveis foram semelhantes nos subgrupos HIFs. Conclusão: Na AB ocorre hipóxia tecidual hepática. Os dados sugerem a existência de hipóxia tecidual progressiva nos fígados afetados pela AB, associada ao desaparecimento de ductos biliares e à piora do quadro obstrutivo biliar. / Background: Biliary atresia (BA) includes a complete obstruction of the extrahepatic biliary tract and progressive intrahepatic cholangiopathy, and the nature of these processes remains unclear. An arteriopthy, leading to an ischemic cholangiopathy, can be involved. The immunolocalization of vascular endothelial growth factor A (VEGFA) in arterial branches and bile ducts both within the liver and at porta hepatis from patients with BA suggests ischemia in these structures. The occurrence of hypoxia in the hepatobiliary system in BA needs to be elucidated. Aim: To determinate the presence of hypoxia in the livers from patients with BA, by analyzing the gene expression of hypoxia-inducible factor (HIF) -1α and -2α. Methods: Liver biopsy specimens collected at exploratory laparotomy of age-matched patients with isolated, cytomegalovirus IgM-negative BA (n=32) and intrahepatic cholestasis (IHC, n=9) were evaluated. A sample was ultrafrozen (molecular analysis) and the other was paraffin-embedded (for histological and morphometric analyzes). Gene expression of: HIF-1α, HIF-2α, monocyte chemoattractant protein 1 (MCP1) (biliary fibrosis marker) and cytokeratin 19 (CK19) (cholangiocyte marker) were evaluated by PCRq using TaqMan® probes. The normalizing gene was 18S ribosomal. The extents of fibrosis and ductular reaction were assessed by morphometry. Clinical and laboratory data were prospectively collected. Results: There was higher HIF-1α and HIF-2α expression in BA in comparison with IHC. In BA, the HIF-1α expression was positively correlated with total serum bilirubin (TB). Two groups were observable in BA regarding HIFs: higher (hiHIF, considering as cutoff point a value higher than 3x the median of expression in IHC) and lower (loHIF). Patients with hiHIF-1α were older and presented increased levels of TB and direct-reacting serum bilirubin (DB) than loHIF-1α. Patients with hiHIF-2α presented CK19 expression lower than in loHIF-2α. The other variables were similar in subgroups HIFs. Conclusion: In BA there is hypoxia in the liver tissue, which seems to be progressive and associated with the disappearance of bile ducts and worsening biliary obstruction.

Abstract Biliary carcinoma, biliary fistula with occasional gallstone ileus and primary sclerosing cholangitis (PSC) are serious diseases and present specific diagnostic and therapeutic challenges. Stenting of biliary obstruction has also involved problems, but the reports are contradictory and partly limited. The aim of the present work was to evaluate and compare various imaging modalities in biliary diseases. The study also aimed to evaluate the usefulness of metallic stents in malignant biliary obstruction. The study population consisted of 210 patients with gallbladder carcinoma, bile duct carcinoma, biliary fistula, PSC or malignant biliary obstruction and eight control patients with various hepatobiliary diseases. The imaging findings of 80 patients with gallbladder carcinoma, 58 patients with bile duct carcinoma, and 16 patients with biliary fistula were reviewed. Nine patients with PSC underwent magnetic resonance cholangiography (MRC) and magnetic resonance imaging (MRI) of the liver, ultrasonography (US) of the liver and the bile ducts and endoscopic retrograde cholangiography (ERC). Eight control patients had had MRC and MRI of the liver and ERC. The medical records and radiographs of 39 patients with malignant biliary obstruction treated with percutaneously inserted metallic stents were also analysed. The stents included 48 Wallstents and seven Memotherm stents. In cases of gallbladder carcinoma, US visualised the primary tumour in 68 % and computed tomography (CT) in 57 % of the cases examined, but both methods were insufficient for accurate staging. In bile duct carcinoma, US revealed the primary tumour in 63 % and CT in 44 % of the cases examined. Both methods were sensitive in diagnosing peripheral intrahepatic cholangiocarcinoma, but inaccurate for more distal bile duct carcinoma or abdominal spread. The infiltrating type of gallbladder carcinoma and bile duct carcinoma were difficult to detect. US and CT were sensitive in revealing bile duct obstruction. The patients with biliary fistula and gallstone ileus had undergone various examinations with pathological, but not diagnostic results, and there was often a delay to diagnosis. Imaging did not reveal any of the ten spontaneous fistulas, but CT showed one of the five cases of gallstone ileus, and Gastrografin® meal revealed the single case of Bouveret's syndrome. Fistulography or cholangiography revealed all but one of the six iatrogenic fistulas. A nonvisualised or shrunken gallbladder at US should raise a suspicion of biliary enteric fistula in an appropriate clinical setting. MRC-MRI depicted the changes of PSC correctly in nine patients (radiologist 1) and in eight patients with one false positive finding (radiologist 2) in a blinded analysis. In the segmental comparison MRC missed especially bile duct dilatations. MRC was too pessimistic in the evaluation of the predictors of poor outcome. US detected features suggestive of PSC in eight patients (radiologist 3). US was unable to indicate the predictors of poor outcome. Of the patients with metallic stents in malignant biliary obstruction, 30 % had early and 66 % late complications, including stent obstructions, which occurred in 27 % of the patients at a mean of 4.4 months. The cause was mostly tumour ingrowth or overgrowth. The 25-week and 50-week patency rates were 71 % and 42 %. The patency rates of the patients with cholangiocarcinoma were significantly the lowest. There was also a tendency towards lower patency with less dilatation of the stents, an increasing number of the stents, longer strictures and hilar strictures. Many other complications were infectious. 31 % of the patients had late reinterventions.

Orientadores: Ilka de Fátima Santana Ferreira Boin, Artur Udelsmann / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-27T00:05:18Z (GMT). No. of bitstreams: 1 Jorge_GracindadeLourdes_D.pdf: 6636878 bytes, checksum: 9167ec95670521d52d8c88a19fc3ceb9 (MD5) Previous issue date: 2015 / Resumo: A oclusão vascular temporária do fluxo hepático é um dos procedimentos essenciais nas cirurgias hepáticas. Muitas pesquisas relacionadas à isquemia e reperfusão (I/R) em ratos Wistar, seja através de interrupção por pouco tempo, ou período maior, têm demonstrado sérias complicações causadas por lesões de I/R. Pesquisas demonstram grandes alterações metabólicas e fisiológicas quando analisadas durante, ou nas primeiras horas após o experimento. O objetivo deste trabalho foi avaliar as alterações hepáticas morfológicas e bioquímicas tardias, ocorridas após pinçamento total ou parcial do hilo hepático em ratos Wistar. Um total de 26 ratos Wistar, machos, peso médio 315,5 ± 61,5g foram utilizados em dois estudos. No primeiro estudo, 12 ratos foram divididos em dois grupos: Grupo Pinçamento do Ducto Biliar Comum (PDBC; n=6) foram submetidos à anestesia com tiopental sódico iv, à incisão abdominal até 2cm, tendo o ducto biliar isolado, dissecado e pinçado por 10 minutos. Após este tempo, a pinça foi retirada e a incisão fechada. Grupo Operação Simulada I (OSI; n=6) em condições de normalidade, os animais foram submetidos unicamente à anestesia e laparotomia e, posteriormente, a exames de controle. Nos dois grupos após o 28ºdia foram realizadas biópsias hepáticas e exames bioquímicos seguidos de eutanásia dos animais. Observamos que 83% dos animas do grupo PDBC apresentaram dilatação do colédoco, com alterações histológicas hepáticas: proliferação ductular, formação de septos, focos de necrose do parênquima, com formação de micro abcessos e alterações dos exames bioquímicos, quando comparados aos animais do grupo OSI (p < 0,05). No segundo estudo, 14 animais foram anestesiados com ketamina 5% (30mg/Kg) e xylazina 2% (30mg/Kg) via intraperitoneal. No grupo clampeamento intermitente do pedículo hepático (CIPH; n=7) os animais foram submetidos à incisão em U no abdome; o pedículo hepático foi isolado, dissecado e submetido a pinçamento, com micro pinça, intermitente por 4 ciclos de 5 minutos de isquemia, seguidos de 5 minutos de reperfusão, e a incisão foi fechada. No Grupo Operação Simulada II (OSII; n=7) os animais foram submetidos à anestesia, laparotomia e manipulação do pedículo hepático e,posteriormente, ao controle dos exames. Em todos os animais no 35o dia, após jejum de 12 horas, foi realizada nova anestesia para coleta da biópsia hepática e sangue para dosagem de alanina amino transferase (ALT) e de aspartato amino transferase (AST). A análise estatística foi realizada pelo teste Mann-Whitney para comparação de médias com significância de 5%. Observamos que todos os animais do grupo CIPH apresentaram dilatação do colédoco e aumento significativo nas enzimas hepáticas (p<0,05). Na avaliação histológica constatamos proliferação ductular (100% dos casos), septos porta-porta (42,8%), formação de nódulos (42,8%), focos de necrose (14,2%) e rolhas de bile (14,2%). No grupo OSII estas alterações não foram encontradas. Concluímos que o pinçamento do ducto biliar (10 minutos) foi suficiente para gerar importantes alterações morfológicas hepáticas e do colédoco, confirmadas através de análise enzimática e histológica, podendo, portanto, ser utilizado como modelo de obstrução biliar, visando estudos semelhantes. Constatamos, também, que o pinçamento intermitente do pedículo hepático provocou lesões semelhantes na árvore biliar e no parênquima hepático / Abstract: The temporary vascular occlusion of the hepatic blood flow is one of the essential procedures in hepatic surgery. Many researches are related to ischemia and reperfusion (I/R) in rats, either through interruption for a short time period or higher and all has shown serious complications caused by I/R injury. Researches have demonstrated, in the early analysis severe metabolic and physiological disorders but there are not reports about hepatic injuries after late analysis. The objective was to assess the morphological and biochemical hepatic late alterations occurring after total or partial hepatic pedicle clamping, in Wistar rats. A total of 26 male Wistar rats, weighting 315.6 ±61.9g were used in two studies. In the first, 12 rats were distributed into two groups: bile duct clamping group (BDCG; n = 6); anesthetized with thiopental sodium; with bile duct dissection, isolation and clamped for 10 minutes. After this time, the clamp was removed and the incision was closed. In simulated operation group I (SOGI; n = 6) the animals were submitted solely to anesthesia and laparotomy and subsequently control exams.On the 28th day, liver biopsies and biochemical exams were performed. All animals were sacrificed while still under anesthesia. We observed that 83% of the animals of BDCG group showed dilation of the common bile duct with hepatic histological changes such as ductular proliferation, septa formation, parenchymal foci of necrosis with formation of micro abscesses and changes of biochemical tests when compared to SOGI (p<0.05).In the second study, 14 animals were anesthetized with ketamine 5% (30mg/kg) and xylazine 2% (30mg/kg)intraperitoneally. In intermittent Hepatic Pedicle Group (IHPC; n = 7) the animals had the hepatic pedicle isolated, dissected and submitted to clamping applying 4 cycles of 5 minutes of ischemia followed by 5 minutes of reperfusion, and the incision was closed.In group operation simulated II (SOGII; n = 7), the animals were anesthetized, laparotomy and manipulation of the hepatic pedicle were performed. On the 35th day, after 12 hours fasting, anesthesia wasinduced for liver biopsy and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) collection. The Mann-Whitney test for comparison of means with significance of 5% was used. In result all the animals of IHPC group had a dilated common bile duct and the significant increase in hepatic enzymes (p <0.05). In histological evaluation we found ductular proliferation (100% of cases), septa port-portal (42.8%), nodules formation (42.8%), foci of necrosis (14.2%) and bile plugs (14.2%). In the group SOGII these changes were not found. We conclude that the short clamping time of the bile duct (for 10 minutes) was enough to cause major hepatic and bile duct morphological changes confirmed by enzymatic and histological analysis, and may therefore be used as biliary obstruction model in order to similar studies. We also noted that the intermittent clamping of the hepatic pedicle caused similar injuries in the biliary tree and in the hepatic parenchyma / Doutorado / Fisiopatologia Cirúrgica / Doutora em Ciências

Gangliosides are sialic acid-containing glycosphingolipids located on the cell surface of all animal cell types. They play a role as receptor molecules, share in cell-to-cell interaction and protect the cell against harmful environmental factors by increasing of rigidity of cell surface. This diploma thesis studies an influence of experimental cholestasis on hepatic ganglioside composition. Cholestasis was induced by bile duct ligation in Wistar rats. A significant increase of total lipid bound sialic acid and b-series gangliosides (GD1b, GT1b, event. GD3) was found in cholestatic liver when compared with controls. These results found in obstructive cholestasis correspond with the results Majer et al. Biomed. Chromatogr., 21, 446-450 (2007), described in 17α− ethinylestradiol induced cholestasis, but the increase of b-series gangliosides was milder in our study. As a second point, an effect of modulated heme-oxygenase 1 (HO-1) activity was investigated in cholestatis induced bile duct ligation (HO-1 activator- hemine, HO-1 inhibitor- Sn-mesoporphyrin). An increase of a total lipid sialic acid was found in Sn-mesoporphyrin treated animals, but a decrease of some a- and b- series gangliosides was observed. In group with activated HO-1 total sialic acid increased, but the composition of gangliosides...

Gangliosides are sialic acid-containing glycosphingolipids located on the cell surface of all animal cell types. They play a role as receptor molecules, share in cell-to-cell interaction and protect the cell against harmful environmental factors by increasing of rigidity of cell surface. This diploma thesis studies an influence of experimental cholestasis on hepatic ganglioside composition. Cholestasis was induced by bile duct ligation in Wistar rats. A significant increase of total lipid bound sialic acid and b-series gangliosides (GD1b, GT1b, event. GD3) was found in cholestatic liver when compared with controls. These results found in obstructive cholestasis correspond with the results Majer et al. Biomed. Chromatogr., 21, 446-450 (2007), described in 17ethinylestradiol induced cholestasis, but the increase of b- series gangliosides was milder in our study. As a second point, an effect of modulated heme-oxygenase 1 (HO-1) activity was investigated in cholestatic rats (HO-1 activator- hemine, HO- 1 inhibitor- Sn- mesoporphyrin). An increase of a total lipid sialic acid was found in Sn-mesoporphyrin treated animals but without significant changes in gangliosides composition. Lipid sialic acid and gangliosides were not changed in animals with hemine activated HO-1. Expression of mRNA of key...

This thesis is focused on the study of glycosphingolipids in the rat liver in different types of cholestasis and the effect of oxidative stress on changes in the composition and localization of gangliosides. First, it was necessary to optimize the immunochemical detection of glycosphingolipids. GM1 ganglioside was selected as a representative of a large glycolipid family. We found that minimum water content in the fixing solution was a key condition for fixation of histological sections. Optimized method of GM1 detection was subsequently used in in vivo experiments. We have demonstrated that estrogen-induced cholestasis characterized by high concentrations of bile acids and increased oxidative stress caused changes in the synthesis and distribution of liver gangliosides. HMOX induction is associated with a reduction in oxidative stress level and accompanied by normalization in GSL content. In experiments with obstructive cholestasis, we found that changes in the distribution and synthesis of gangliosides were not strictly specific to a particular type of cholestasis. We assume that it represents a general mechanism of hepatoprotection. We also confirmed the important role of bilirubin, product of HMOX reaction, in protection of hepatocytes against oxidative damage caused by high concentrations of...

In cystic fibrosis (CF), pancreatic insufficiency and a diminished bile acid pool cause malabsorption of important nutrients and dietary components leading to deficiency, poor nutritional status, and oxidative stress. Of particular significance is the malabsorption of fat-soluble nutrients and antioxidants, which are important for normal immune and neurologic function. Patients with CF often are deficient in these compounds despite supplementation with the current standard of care therapy. The objective was to compare the pharmacokinetic profile of this water-soluble vitamin E formulation (Aqua-E) with an oil-based softgel formulation in a malabsorbing patient population. Patients with CF who had documented malabsorption were recruited for participation in this pharmacokinetic study. Patients who met inclusion and exclusion criteria discontinued vitamin E supplementation, except for that in a multivitamin, for 7 to 21 days before the day of dosing. Patients were randomized to a single dose of 20 ml of Aqua-E or three oil-based softgels, which contained equivalent amounts of tocopherols. Blood was drawn from patients at time 0, 2, 4, 8, 24, 48, and 168 hr and analyzed for tocopherols. Eight patients were enrolled in the study and randomized to Aqua-E or softgels. The primary outcome, the absorption of γ-tocopherol in Aqua-E (AUC=115 μg/ml*hr), was significantly greater than that of oil-based softgels (AUC=25.3 μg/ml*hr; P=0.013). Total-tocopherols (α+γ +δ) in Aqua-E (AUC=294 μg/ml*hr) showed a strong trend toward increased absorption compared with that of oil-based softgels (AUC=117 μg/ml*hr; P=0.09). In conclusion, this novel, water-soluble formulation showed a marked and statistically significant increase in absorption of γ-tocopherol in malabsorbing patients with CF compared with an oil-based formulation.

1 Abstract In this thesis I have focused on the role of lipids in the pathogenesis of liver diseases, specifically on cholestasis and non-alcoholic fatty liver disease (NAFLD). The first major aim was to clarify the changes in liver ganglioside metabolism in various types of cholestasis and to elucidate the role of heme oxygenase-1 (HMOX1) and associated oxidative stress. The second objective was to determine the effects of n-3 polyunsaturated fatty acids (n-3 PUFA) administration on NAFLD development in a rodent dietary model of NAFLD and in patients with metabolic syndrome and NAFLD. Our results suggest that increased ganglioside biosynthesis and their re-distribution might represent a general protective mechanism of hepatocytes under cholestatic conditions (both estrogen-induced and obstructive aetiology). These changes are closely related to oxidative stress and might protect hepatocytes against deleterious effect of accumulated bile acids. The lack of HMOX1 activity and subsequent oxidative stress potentiate pathological changes in the liver and resulted in tissue-specific modulation of synthesis and re-distribution of gangliosides (in vivo and in vitro). Contrary to it, HMOX1 activation has an opposite effect and may represent a general hepatoprotective mechanism. We have proven that observed changes...