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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Doença esteatóica não alcoólica do fígado: comparação das alterações histológicas hepáticas entre modelo murino e pacientes obesos

Palma, Luana Carneiro January 2013 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2013-10-15T15:33:27Z No. of bitstreams: 1 Luana Palma. Doença esteatotica...2012.pdf: 6491139 bytes, checksum: 17714fa9ab206495fbf5e1aa05890deb (MD5) / Made available in DSpace on 2013-10-15T15:33:27Z (GMT). No. of bitstreams: 1 Luana Palma. Doença esteatotica...2012.pdf: 6491139 bytes, checksum: 17714fa9ab206495fbf5e1aa05890deb (MD5) Previous issue date: 2013 / Universidade Federal da Bahia. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / A Doença Esteatótica Não Alcoólica do Fígado (do inglês Nonalcoholic Fatty Liver Disease – NAFLD) é uma doença crônica hepática de caráter espectral, que vai desde a esteatose simples até a esteato-hepatite não alcoólica. A progressão para cirrose e carcinoma hepatocelular têm sido descrita. A NAFLD apresenta aspectos histológicos semelhantes à doença hepática relacionada ao álcool (esteatose, inflamação lobular, corpúsculos de Mallory e fibrose), mas acomete indivíduos com história negativa de consumo excessivo de álcool. A NAFLD é uma das principais doenças crônicas hepáticas mundiais, e os indivíduos obesos representam a maioria dos casos da doença. Os mecanismos envolvidos na progressão da esteatose para esteato-hepatite não são bem compreendidos. Neste aspecto, modelos murinos da NAFLD têm sido frequentemente utilizados para elucidação destes mecanismos. A maioria dos modelos disponíveis é resultante de modificações genéticas e/ou nutricionais e, em geral, não simulam as alterações metabólicas e histológicas comumente vistas em pacientes com NAFLD. Em nosso grupo, foi proposto um novo modelo de NAFLD. Camundongos C57BL/6 alimentados com dieta rica em gordura (High Fat - HF) demonstraram alterações metabólicas e histológicas sugestivas de NAFLD. O objetivo do presente trabalho foi comparar alterações histológicas hepáticas presentes nestes camundongos com as alterações observadas em pacientes obesos. Amostras de fígados de pacientes obesos e de camundongos alimentados com a dieta HF foram utilizadas. Os tecidos hepáticos foram corados em Hematoxilina & Eosina e Picrossírius Red para avaliação das alterações hepáticas (esteatose, balonização, inflamação, corpúsculos de Mallory-Denk e fibrose). Além disso, foi realizada imunoistoquímica para avaliação da presença de células estrelares ativadas e de células progenitoras hepáticas, células envolvidas na fibrose e no desenvolvimento de carcinoma hepatocelular, respectivamente. Os resultados demonstraram que os fígados de todos os pacientes obesos exibiram esteatose macrovacuolar, balonização hepatocelular, inflamação lobular e fibrose perissinusoidal, o que caracterizou estes pacientes como portadores da NAFLD. As mesmas alterações foram observadas em fígados de camundongos alimentados com a dieta HF. As células estrelares ativadas foram observadas em todos os pacientes obesos, assim como em camundongos de dieta HF. As células progenitoras hepáticas foram observadas na maioria dos pacientes obesos. O fígado de todos os camundongos alimentados com dieta HF exibiram células progenitoras hepáticas. A partir dos dados obtidos, pode-se concluir que fígados de camundongos alimentados com dieta HF exibem alterações histológicas hepáticas similares às observadas em pacientes obesos. Isto abre perspectivas para a utilização do modelo proposto em estudos que busquem elucidar os mecanismos envolvidos na patogênese da NAFLD. / Nonalcoholic Fatty Liver Disease (NAFLD) is a chronic liver disease ranging from simple steatosis to nonalcoholic steatohepatitis. The progression to cirrhosis and hepatocellular carcinoma has been reported. The NAFLD shows histological features similar to alcohol-related liver disease (steatosis, lobular inflammation, fibrosis and Mallory-Denk bodies), but affects individuals with no history of excessive alcohol consumption. The NAFLD is a major chronic hepatic disease in the world, and obese individuals represent the majority of cases of the disease. The mechanisms involved in the progression of steatosis to steatohepatitis are not well understood. In this regard, murine models of NAFLD have been frequently used for elucidation of these mechanisms. Most available models are the result of genetic or nutritional modifications, and generally do not mimic metabolic and histologic changes commonly seen in patients with NAFLD. In our group, we have proposed a new model of NAFLD. Mice fed high fat diet (HF diet) demonstrated metabolic and histological features suggestive of NAFLD. The aim of this study was to compare liver histological alterations present in these mice with the changes observed in obese patients. Samples of livers of obese patients and mice fed HF diet were used. For assessment of liver alterations, such as steatosis, ballooning, inflammation, Mallory- Denk bodies and fibrosis, tissues were stained with hematoxylin & eosin and picrossirius red. In addition, the presence of activated stellate and progenitor liver cells was estimated using immunohistochemistry. The results show that the livers of all obese patients exhibited macrovesicular steatosis, hepatocellular ballooning, perisinusoidal fibrosis, and lobular inflammation, which characterized these patients with NAFLD. Similar changes were observed in livers of mice that fed the HF diet. Activated stellate cells were observed in all obese patients as well as in mice HF. Hepatic progenitor cells were observed in most obese patients. The liver of all animals fed the HF diet exhibited liver progenitor cells. From the data obtained, it can be concluded that livers of mice fed with HF diet exhibit liver abnormalities similar to those observed in obese patients. This opens perspectives for the use of the proposed model in studies that seek to elucidate the mechanisms involved in the pathogenesis of NAFLD.
162

Influência da vitamina D sérica na adiponectina, visfatina e resistina nas alterações histológicas no fígado de pacientes com doença hepática gordurosa não alcoólica

Cavallari, Karelin Alvisi January 2016 (has links)
Orientador: Sergio Alberto Rupp de Paiva / Resumo: A doença hepática gordurosa não alcoólica (DHGNA) é um conjunto de desordens caracterizado pela esteatose macrovesicular no consumo de álcool insuficiente para causar lesão hepática. A disfunção do tecido adiposo e a alteração no padrão de citocinas têm de destacado no desenvolvimento da doença, especialmente a adiponectina, visfatina e resistina. Além disso, a vitamina D parece modular a expressão de citocinas, podendo influenciar o desenvolvimento da doença. O objetivo do presente estudo foi avaliar a associação das alterações histológica com a concentração sérica de adiponectina, visfatina, resistina e vitamina D em pacientes com DHGNA. Foram recrutados 82 pacientes com DHGNA. Foi realizada anamnese clinica e nutricional, avaliação antropométrica e de composição corporal, consumo alimentar, biomarcadores da DHGNA, dosagens séricas de adiponectina, visfatina, resistina, 25hidrovitamina D e biópsia hepática em todos os pacientes no intervalo de no máximo 3 meses. Foi observado na amostra 83% dos pacientes do sexo feminino, maioria branco,s 79% sedentários e 96% obesos. Verificamos associação da adiponectina como fator protetor para fibrose (OR:0,88; 95% CI0,78-1; p=0,05) e da visfatina como fator de risco para fibrose perisinusoidal (OR:2,66; 95% CI:1,3-5,44; p=0,007) e fibrose (OR:2,96; 95% CI1,19-7,35; p=0,02). Em relação à VD, observamos a presença de hipovitaminose D em 60% dos pacientes; com influência da concentração sérica de VD na visfatina como fator de proteção par... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Non-alcoholic fatty liver disease (NAFLD) is a spectrum of disorders characterized by macrovesicular steatosis without enough alcohol to cause liver damage. The adipose tissue dysfunction and the adipokines pattern changes have been emphasized in non-alcoholic fatty liver disease development, especially adiponectin, resistin and visfatin. In addition, vitamin D may modulate the expression of adipokines, therefore influencing the disease development. The aim of the study was to evaluate the association of serum adiponectin, visfatin, resistin and vitamin D with histological changes in NAFLD patients. Thus, 82 NAFLD patients were enrolled. Nutritional and clinical anamneses, diet, physical activity, anthropometric parameters, a set of biomarkers related to NAFLD were evaluated within a range of 3 months. Out of the 82 patients, 83% were female, most of then whites, 79% sedentary and 96% obese. Adiponectin has been associated as a protective factor for fibrosis (OR: 0.88; 95% CI0,78-1; p = 0.05); while visfatin as a risk factor for perisinusoidal fibrosis (OR: 2.66; 95% CI : 1.3 to 5.44; p = 0.007) and fibrosis (OR: 2.96; 95% CI1,19-7,35; p = 0.02). Vitamin D deficiency was observed in 60% of patients. Vitamin D influences visfatin as a protective factor for non-alcoholic steato-hepatitis (NASH) (OR: 0.84; 95% CI: 0.73 to 0.979; p = 0.025) and resistin as a risk factor for lobular inflammation (OR: 1 13, 95% CI: 1-1.28; p = 0.051). Adipokines are associated with NAFLD hepatic... (Complete abstract click electronic access below) / Mestre
163

Quantificação da esteatose hepática: avaliação de diferentes estratégias de medidas pela ressonância magnética nos casos de esteatose com distribuição homogênea e heterogênea / Quantification of hepatic steatosis: evaluation of different strategies measured by MRI in cases of steatosis with homogeneous and heterogeneous distribution

Eloá de Castro Noguerol 18 May 2015 (has links)
A esteatose hepática é caracterizada histologicamente pelo acúmulo de triglicerídeos no citoplasma dos hepatócitos. A biópsia ainda é o padrão ouro para diagnóstico e avaliação da gravidade, no entanto, é um método invasivo e sujeita a erro de amostragem. Com os avanços dos métodos diagnósticos por imagem, a RM se tornou um método bem estabelecido para detecção e quantificação da esteatose. A maneira mais simples é a obtenção do cálculo da fração de gordura pela técnica gradiente-eco desvio químico. Todavia, não há estudos demonstrando a melhor forma de medir a intensidade de sinal para esse cálculo. Em nosso estudo, através da revisão de exames de RM, avaliamos três diferentes estratégias de medidas para quantificação com amostra de conveniência com 74 exames apresentando esteatose pareados em dois grupos, esteatose homogênea (n=37) e heterogênea (n=37). No grupo de esteatose heterogênea, o uso de ROI de 1cm² para medir a intensidade de sinal na área mais alterada apresentou variações significativas na quantificação, enquanto a média de quatro ROIs de 1cm² ou a segmentação de área representativa em corte axial não apresentaram variações significativas. Na esteatose hepática homogênea, qualquer estratégia utilizada não demonstrou diferença significativa. O coeficiente de correlação intraclasse variou entre 0,96 e 0,99, com IC 95% de 0,93-0,99. Assim, a quantificação da gordura hepática por RM utilizando apenas um ROI é menos representativa, principalmente na esteatose heterogênea. Não houve diferença significativa entre a obtenção da média de 4 ROIs e a segmentação de área representativa do parênquima. / Hepatic steatosis is characterized histologically by the triglyceride accumulation in the cytoplasm of hepatocytes. A biopsy is still considered the gold standard for diagnosis and assessment of severity, however, is an invasive and subject to sampling error method. With the improvement of diagnostic imaging methods, MRI has become a well-established method for the detection and quantification of liver fat. The easiest way is to obtain the calculation of the fat fraction by GRE technique with chemical shift technique. However, there are no studies demonstrating the best way to measure the signal intensity for this calculation. In our study by MRI review, we evaluate three different strategies for measuring the signal intensity with a convenience sample of 74 exams showing steatosis paired into two groups, diffuse steatosis (n = 37) and heterogeneous (n = 37). In heterogeneous steatosis group, the strategy with a ROI of 1 cm² to measure the signal intensity in the most altered area showed significant variations in the quantification, while the average of four ROIs of 1cm² or representative target area in axial section did not vary significant. In diffuse hepatic steatosis, any strategy used showed no significant difference. The intraclass correlation coefficient ranged between 0.96 and 0.99, with 95% of 0.93-0.99. Thus, the quantification of fat liver by MRI using only ROI is less representative, especially in heterogeneous steatosis. There was no significant difference between the average of 4 ROIs strategy and the strategy of representative segmentation area of parenchyma.
164

Apoptose induzida por palmitato em células HEPG2 depende da produção de TNF-Alfa / Palmitate-induced apoptosis in HEPG2 cells is dependent on the increased production of TNF-Alpha

Silva, Carolina Solon da, 1982- 21 August 2018 (has links)
Orientador: Gabriel Forato Anhê / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T11:57:04Z (GMT). No. of bitstreams: 1 Silva_CarolinaSolonda_M.pdf: 587503 bytes, checksum: cd74a1063d709369d29c9a998e1cc9a4 (MD5) Previous issue date: 2012 / Resumo: A prevalência de esteato hepatite não alcólica (NASH) aumenta de 20% em indivíduos magros para 80% em pacientes obesos com inflamação hepática caracterizada por elevados níveis de TNF-alfa. Um dos eventos que caracteriza a evolução para NASH é a marcante morte de hepatóciotos resultante da ação do excesso de ácidos graxos livres circulantes. O mecanismo pelo qual o palmitato induz a apoptose é dependente, entre outros parâmetros, do aumento dos níveis de espécies reativas de oxigenio (EROS). O objetivo do presente trabalho foi avaliar se a apoptose de hepatócitos induzida pelo palmitato é dependente do aumento da produção de TNF-alfa. Para testar tal hipótese, utilizamos o Infliximabe, um anticorpo monoclonal específico anti-TNF-alfa, como ferramenta farmacológica para reverter as injúrias provocadas pelo palmitato. Foi observado que após 6 horas de tratamento com o palmitato houve um aumento de expressão de mRNA de TNF-alfa levando a um aumento de apoptose 24 horas após à exposição com o ácido graxo. Este fenômeno concordou temporalmente com um aumento na fosforilação das proteínas IkK, IKbeta e JNK, indicativo de ativação da via de sinalização do TNF-alfa. A apoptose induzida pelo palmitato foi revertida pela adição de um inibidor geral de síntese proteica (Ciclohexamida) ou de um anticorpo neutralizante para o TNF-alfa circulante. Além disso, a produção de EROs e a disfunção mitocondrial induzidas pelo palmitato também foram revertidos por estas estratégias farmacológicas. Com base em tais resultados, concluímos que a apoptose, o acúmulo de EROs e da disfunção mitocondrial induzidas pelo palmitato em células HepG2 são dependentes da produção de TNF-alfa / Abstract: In the last three decades, the prevalence of overweight and obesity has been continuously increasing. Obesity is a risk factor for developing a series of diseases such as whole-body insulin resistance and type 2 diabetes mellitus. Adipose tissue, originally considered merely energy storage, today is recognized as an endocrine organ able of secreting a variety of cytokines, hormones and other substances with specific biological activities, such as saturated fatty acids. Both long chain saturated fatty acids, like palmitate, and the proinflammatory cytokines, as TNF-alfa, are known to activate signaling pathways that promote apoptosis. The mechanism by which the palmitate induces apoptosis is dependent on cell type, for example, human hepatocellular carcinoma line (HepG2) treated with palmitate led lipotoxicity and to increased levels of reactive oxygen species (ROS). Thus, the objective of this study was to evaluate whether apoptosis in HepG2 cells is dependent on increased production of TNF-alfa induced by treatment with palmitate. To test this hypothesis, we used the Infliximab, a monoclonal antibody anti-TNF-alfa, as a pharmacological tool to reverse injuries caused by palmitate. We observed that palmitate increased the mRNA for TNF-alfa and phosphorylation of IkK, Ikbeta and JNK, all indicative of activation of inflammatory signaling pathways. Apoptosis induced by palmitate was suppressed by simultaneous treatment with cycloheximide or infliximab. Furthermore, the production of ROS and mitochondrial dysfunction induced by palmitate were also suppressed by these two pharmacological strategies. Based on these results, we conclude that apoptosis and related events such as increased ROS production and mitochondrial dysfunction induced by palmitate in HepG2 cells are dependent on autocrine action of TNF--alfa / Mestrado / Farmacologia / Mestra em Farmacologia
165

L’autophagie macrophagique protège contre l'atteinte hépatique et la fibrose au cours de la maladie alcoolique du foie / Macrophage autophagy protects against alcohol-induced liver injury and fibrosis

Lodder, Jasper 09 December 2014 (has links)
La maladie alcoolique du foie et la stéatopathie métabolique figurent parmi les principales causes de morbi-mortalité dans les pays occidentaux en raison d'une accumulation progressive d'une fibrose dans le foie. Il n'existe à ce jour aucune molécule sûre et efficace dont l'effet antifibrosant ait formellement été démontré chez l'homme. Les macrophages du foie jouent un rôle central dans la pathogenèse de la fibrose hépatique en produisant des cytokines pro inflammatoires et fibrogéniques qui favorisent l'activation des cellules fibrogéniques du foie. L'autophagie est un processus de dégradation lysosomale qui présente des propriétés anti-inflammatoires en inhibant la production des cytokines pro-inflammatoires.Dans une première étude, nous démontrons que des souris invalidées pour le gène ATG5 dans la lignée myéloïde (Atg5Mye-/-) traitées par le CCl4, produisent une fibrose hépatique aggravée par rapport aux souris sauvages. En outre, les souris Atg5Mye-/- présentent une augmentation de l'atteinte hépatocytaire, du recrutement de cellules inflammatoires (monocytes et neutrophiles) et de la production des cytokines IL-1α et IL-1β. De plus, l'expression des marqueurs fibrogéniques est augmentée dans les myofibroblastes exposés à un milieu conditionné de macrophages ATG5-/- traités par le LPS par comparaison au milieu conditionné de macrophages sauvages. Ces effets sont reversés près prétraitement du milieu conditionné de macrophages ATG5-/- avec des anticorps neutralisant l'IL-1α et l'IL-1β. Enfin, l'administration simultanée d'un antagoniste de l'IL-1R1 aux souris Atg5Mye-/- traitées par le CCl4, atténuée l'atteinte hépatique et la fibrose, suggerant que les propriétés anti-inflammatoires et anti-fibrogéniques dans le foie de l'autophagie macrophagique sont influencés par l'IL-1α et l'IL-1β.Dans un deuxième temps, nous avons montré que les souris invalidées pour le récepteur CB2 dans les cellules myéloïdes (CB2Mye−/−) exprimaient fortement des gènes pro-inflammatoires et déclaraient une stéatose hépatique lors de l'induction alcoolique en comparaison aux souris sauvages. L'activation du récepteur CB2 par JWH-133 augmente l'autophagie des macrophages du foie chez les souris ayant reçu une alimentation alcoolisée, alors que cette autophagie est inhibée pour les souris CB2Mye−/− dans les mêmes conditions d'alimentation. Sur des cultures de macrophages péritonéaux, nous avons montré que JWH-133 limite l'induction des gènes inflammatoires provoquée par le LPS dans les macrophages péritonéaux sauvages, sauf pour les cellules déficientes en ATG5-, suggérant que les effets anti-inflammatoires et anti-stéatogènes du récepteur CB2 sont médiés par l'autophagie. En effet, les agonistes du récepteur CB2 pourraient jouer un rôle protecteur contre l'inflammation du foie et la stéatose induites par l'alcool chez l'individu sauvage, mais pas chez les souris ATG5Mye−/−.Ces résultats i) présentent l'autophagie des macrophages comme un nouveau processus anti-inflammatoire qui régule la fibrose hépatique et ii) identifient le récepteur CB2 comme un régulateur de l'autophagie dans les macrophages, qui protège de la stéatose induite par l'alcool par inhibition de l'inflammation hépatique. / Alcohol abuse and non-alcoholic fatty liver disease (NAFLD) are leading causes of liver-related morbi-mortality in Western countries that may lead to accumulation of fibrosis in the liver. Efficient treatments are lacking and there is currently no molecule approved for the treatment of liver fibrosis. Hepatic macrophages play a pivotal role in the initiation and perpetuation of the inflammatory response in fatty liver disease and in progression to fibrosis. Autophagy is a lysosomal degradation pathway that limits the production of pro-inflammatory cytokines. The aim of my thesis was to explore the contribution of macrophage autophagy on alcohol-induced liver injury and fibrosis.In a first study, we show that mice invalidated for the autophagy-gene ATG5 in myeloid cells (Atg5Mye-/- mice) develop exacerbated fibrosis as compared to WT littermates in response the hepatotoxin CCl4. Moreover, Atg5Mye-/- mice produce higher hepatic levels of IL-1α and IL-1β, and show enhanced inflammatory cell recruitment associated with exacerbated liver injury. Hepatic myofibroblasts exposed to the conditioned medium of macrophages from Atg5Mye-/- mice displayed increased profibrogenic gene expression, which could be blunted by neutralizing IL-1α and IL-1β in the conditioned medium of Atg5-/- macrophages. Finally, administration of an IL-1R1 antagonist to Atg5Mye-/- mice exposed to carbon tetrachloride blunted liver injury and fibrosis, revealing that the deleterious effects of macrophage autophagy invalidation are mediated through IL-1α/β.In a second study, we generated mice invalidated for CB2 receptor (CB2Mye−/− mice) in myeloid cells. These mice showed enhanced alcohol-induced pro-inflammatory gene expression and hepatic steatosis as compared to WT littermates. Conversely, mice administered JWH-133 show reduced alcohol-induced liver injury. Activation of the CB2 receptor by JWH-133 increased macrophage autophagy in the livers of alcohol-fed mice, whereas autophagy was inhibited of alcohol-fed CB2Mye−/− mice. In cultured peritoneal macrophages, JWH-133 reduced the induction of inflammatory genes by LPS in WT peritoneal macrophages, but not in ATG5-deficient cells, suggesting that the anti-inflammatory and anti-steatogenic effects of the CB2 receptor are mediated through autophagy. Indeed, the CB2 agonist could protect against alcohol-induced liver inflammation and steatosis in WT, but not in ATG5Mye−/− mice.These results uncover macrophage autophagy as a novel anti-inflammatory pathway that regulates liver fibrosis, and identify CB2 receptor in macrophages as regulator of autophagy that protects from alcohol-induced steatosis by inhibiting hepatic inflammation. Exploiting macrophage autophagy may therefore be an interesting novel target in the treatment of chronic liver disease.
166

Progression et tests diagnostiques de la stéatose hépatique non alcoolique / Progression and diagnostic methods in non-alcoholic fatty liver disease

Fedchuk, Larysa 30 September 2014 (has links)
La stéatose hépatique non alcoolique, regroupant la stéatose isolée (NAFLD) et la stéatohépatite non-alcoolique (NASH), est un enjeu de santé publique mondial en raison d’une incidence croissante, en grande partie expliquée par l’augmentation de la prévalence du diabète et de l’obésité. La stéatose hépatique prédit la survenue des complications métaboliques associées à l’insulinorésistance, comme le diabète ou les événements cardiovasculaires. La connaissance de l’histoire naturelle de la NAFLD comporte encore de nombreuses incertitudes. Actuellement le modèle explicatif repose sur une dichotomie entre la stéatohépatite (NASH), qui peut progresser vers la cirrhose et la stéatose isolée ou avec inflammation minime (NAFL) qui jusqu'à présent était considérée comme une condition non évolutive ne progressant pas vers la cirrhose et n'augmentant pas la morbi-mortalité d'origine hépatique. Cette dichotomie conditionne en grande partie la prise en charge de ces patients, ceux avec NAFL étant souvent rassurés par le praticien quant à leur devenir et ne bénéficiant pas d'une surveillance hépatique spécifique. La ponction biopsie du foie est considérée comme un examen de référence, mais son usage en pratique clinique reste limité en raison d’effets indésirables, d’erreurs d'échantillonnage et de la variabilité d’interprétation inter-observateur. Les méthodes non invasives de lésions hépatiques sont devenues une vraie alternative à la biopsie du foie pour la prise en charge des patients ayant une maladie chronique du foie, au cours des dix dernières années. / Non-alcoholic fatty liver disease (NAFLD) covers a spectrum ranging from isolated steatosis to non-alcoholic steatohepatitis (NASH) and is becoming one of the most frequent causes of chronic liver disease, mainly because of its close association with the worldwide epidemic of diabetes and obesity. Liver steatosis can predict the occurrence of metabolic complications associated with insulin resistance, such as diabetes and cardiovascular events. Our understanding of the natural history of NAFLD is still incomplete. Currently, the explicative model is based on a dichotomy between steatohepatitis, considered the progressive form of the disease, which can lead to cirrhosis and isolated steatosis with or without minimal inflammation, which is considered a non-progressive condition that does not impact overall survival or result in liver-related mortality and morbidity. This dichotomy largely determines the management of NAFLD patients: patients without steatohepatitis usually do not undergo specific monitoring for liver disease progression. Liver biopsy is considered the reference diagnostic method but its implementation in clinical practice remains limited due to procedure complexity, invasiveness, cost, potential complications, sampling error and inter-observer variability. Non-invasive methods of hepatic injury have become a real alternative to liver biopsy for the diagnosis of patients with chronic liver disease in the past decade. The aims of this thesis were: 1) to better understand the histological course of the disease, to better identify patients at risk of histological progression based on initial histological findings and to establish a correlation between histological changes and the course of metabolic co-morbidities often associated with NAFLD : 2) to establish factors associated with short-term variability of repeated measurements of elastometry in patients with chronic liver diseases in order to understand how this non invasive procedure can be used for patient monitoring 3) to determine the diagnostic value and limitations of several steatosis biomarkers using liver biopsy as a reference standard in a large cohort of patients with suspected NAFLD. Our study shows that a fraction of patients with isolated steatosis can unambiguously evolve towards well-defined steatohepatitis, and in some of them, bridging fibrosis. The presence of mild lobular inflammation or any amount of fibrosis substantially increases the risk of histological progression in the mid-term while those with steatosis alone are at lowest risk. Patients with disease progression experienced a deterioration of cardio-metabolic risk factors. Our data if validated by independent studies, allow for better stratification of patients at risk of disease progression. The results of this study favor a change in the practices of monitoring and risk assessment of patients with steatosis but without steatohepatitis.
167

Avaliação da condição funcional, capacidade pulmonar, composição corporal e qualidade de vida dos pacientes candidatos a transplante de fígado = Evaluation of functional status, pulmonary capacity, body composition and quality of life of end-stage liver disease patients candidates for surgery / Evaluation of functional status, pulmonary capacity, body composition and quality of life of end-stage liver disease patients candidates for surgery

Santos, Daniele Costa dos, 1981- 26 August 2018 (has links)
Orientadores: Raquel Silveira Bello Stucchi, Ilka de Fátima Santana Ferreira Boin / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T08:25:01Z (GMT). No. of bitstreams: 1 Santos_DanieleCostados_M.pdf: 1085243 bytes, checksum: f6d71bd9d53ba2ba29df2a153ac0ae0a (MD5) Previous issue date: 2014 / Resumo: Introdução: Fatores como perda de massa e função muscular, alterações mecânicas da mobilidade da caixa torácica e diafragma secundárias a ascite e fraqueza muscular juntamente com desnutrição podem induzir à deficiência motora global e à inatividade física, interferindo negativamente nas atividades de vida diária e na qualidade de vida dos indivíduos que possuem doença hepática crônica em fase avançada. Objetivos: Avaliar a capacidade funcional, composição corporal, qualidade de vida e eletromiografia de pacientes hepatopatas crônicos candidatos a transplante de fígado; verificar se existe correlação entre as variáveis funcionais dos indivíduos testados por meio do Teste de Caminhada de 6 minutos (TC6) e as co-variáveis: prova de função pulmonar (PFP), qualidade de vida, eletromiografia de superfície dos músculos reto abdominal e diafragma e composição corporal total. Métodos: Este estudo foi realizado no Ambulatório de Transplante de Fígado da Universidade Estadual de Campinas (UNICAMP) no período de agosto de 2012 a novembro de 2013. Foram incluídos 54 pacientes com doença hepática crônica que possuíam condições clínicas e funcionais de realizarem os testes a serem propostos. Foram submetidos às seguintes avaliações: anamnese, questionário de qualidade de vida "Short Form 36" (SF-36), eletromiografia de superfície (sEMG) dos músculos diafragma e reto abdominal, avaliação da composição corporal por meio da Bioimpedância Elétrica (BIA), TC6 e PFP. Resultados: Foram encontrados scores médios inferiores a 65 no questionário SF-36, bem como a média da distância percorrida no TC6 também foi abaixo dos valores preconizados para população saudável. A distância percorrida no TC6 teve correlação com qualidade de vida e com ângulo de fase da BIA. Foram encontradas também correlações das variáveis respiratórias do TC6 com índice de massa corpórea, PFP e qualidade de vida. Conclusão: Conclui-se que a capacidade funcional e qualidade de vida encontram-se diminuídos em pacientes hepatopatas crônicos em lista de transplante hepático. Adicionalmente, a capacidade funcional apresentou correlações com alterações na qualidade de vida, função pulmonar e composição corporal / Abstract: Introduction: Loss of muscle mass and function, mechanic alterations of chest mobility and the diaphragm due to ascitis and muscular weakness in combination with malnutrition can induce a global motor impairment and physical inactivity, adversely impairing the daily living activities and quality of life in end-stage liver disease patients, candidates for liver transplantation. Objectives: To evaluate functional status, pulmonary function, body composition and quality of life in end-stage liver disease patients, candidates for liver transplantation; to verify if there is a correlation between the functional variables of the individuals tested through the 6-minute walk test (6MWT) and covariables: pulmonary function test (PFP), quality of life, surface electromyography (sEMG) of the diaphragm and rectus abdominis muscles and body composition. Methods: This study was carried out at the Liver Transplant Unit of the State University of Campinas (UNICAMP) from August, 2012 until November, 2013. Fifty four patients with end-stage liver disease were included. The patients underwent the following evaluations: medical history, quality of life questionnaire "Short Form 36" (SF-36), surface electromyography (sEMG) of the diaphragm and rectus abdominis muscles, body composition assessment by Electrical Bioimpedance (BIA), 6MWT and PFP. Results: Scores below to 65 at SF-36 were founded and the distance walked on 6MWT was below to recommended for heathy population. The walked distance was correlated with quality of life and BIA (phase angle). Correlations were found between respiratory variables of 6MWT and body mass index, PFP and quality of life. Conclusion: Functional status and quality of life are impaired in patients with chronic liver disease and candidates for liver transplantation. Additionally, functional status is related to changes in quality of life, pulmonary capacity and body composition / Mestrado / Fisiopatologia Cirúrgica / Mestra em Ciências
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Le microbiote intestinal comme cible thérapeutique dans la maladie alcoolique du foie : implication des acides biliaires et de la pectine / Le microbiote intestinal comme cible thérapeutique dans la maladie alcoolique du foie : implication des acides biliaires et de la pectine

Ciocan, Dragoş Marius 05 December 2018 (has links)
L'alcool est une des principales causes de maladie du foie en Europe avec peu d'options thérapeutiques. Parmi les consommateurs d'alcool, seul certains patients vont évoluer vers des formes sévères d'atteinte hépatique et le microbiote intestinal a été identifié comme cofacteur de cette susceptibilité individuelle. Il interagit avec le foie notamment via la production de métabolites bactériens tels que les acides biliaires secondaires.L'objectif de ce travail a été dans un premier temps d'analyser le microbiote intestinal, au sein d’une cohorte de patients alcooliques à différents stades de la maladie alcoolique du foie, et d’étudier sa relation avec les acides biliaires. Dans un deuxième temps, ce projet avait pour but d’étudier s’il était possible d'améliorer l'atteinte hépatique liée à l'alcool, en modulant le microbiote intestinal, dans un modèle animal de maladie alcoolique du foie.Les patients avec une atteinte hépatique sévère liée à l'alcool ont un profil d’acides biliaires plus hydrophobe, et donc plus toxique, associé à une dysbiose et à des modifications des fonctions bactériennes. Ces modifications des fonctions bactériennes participent à la gravité de la maladie. La modulation du microbiote par la pectine, un prébiotique, permet de prévenir mais également de faire régresser les lésions hépatiques chez la souris. Les effets protecteurs de la pectine sont corrélés avec le métabolisme du tryptophane.Ce travail de thèse montre que le microbiote intestinal et ses métabolites sont une cible thérapeutique potentielle dans la maladie alcoolique du foie. Il ouvre la porte à la réalisation d'essais cliniques chez l'homme dans lesquels nous pourrions limiter la progression des lésions hépatiques liées à l'alcool en contrôlant le microbiote intestinal grâce à l’utilisation de la pectine ou du métabolisme du tryptophane. / Alcohol is one of the main causes of alcoholic liver disease in Europe with few therapeutic options. Among alcohol consumers, only a part of these patients will develop severe liver lesions. This individual susceptibility is driven by intestinal microbiota. Intestinal microbiota interacts with the liver through the production of bacterial metabolites including the secondary bile acids.The aim of my project, was firstly to study the relationship between the intestinal microbiota and the bile acids composition depending on the severity of alcoholic liver disease in a cohort of alcoholic patients. Secondly, I assessed the improvement of alcohol induced liver lesions by changing the intestinal microbiota in a mouse model of alcoholic liver disease.Patients with a severe form of alcoholic liver disease display a higher hydrophobic bile acid pool, more toxic, associated with a specific dysbiosis and changes in the bacterial functions. Changing the intestinal microbiota by using pectin, a prebiotic, prevents and reverts alcohol induced liver injury in mice. These protective effects of pectin involve changes in the tryptophan metabolism.In conclusion, these studies highlight that the intestinal microbiota and its metabolites are potential therapeutic targets for alcoholic liver disease. Moreover, pectin as an alimentary product could be proposed in the management of alcoholic liver disease in humans.
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Mesenchymální kmenové buňky a jejich regenerační a imunomodulační potenciál / Mesenchymal stem cells and their regenerative and immunomodulatory potential

Brychtová, Michaela January 2016 (has links)
Mesenchymal stem cells and their regenerative and immunomodulatory potential Abstract Mesenchymal stem cells (MSCs) possess multidirectional regenerative ability, which, together with their immunomodulatory potential, makes them promising cell type for therapy of wide variety of diseases. Despite ongoing research, which proved MSCs application to be safe, reported effect of MSCs administration on patients is not convincingly beneficial yet. In our work we focused on elucidation of MSCs role in regeneration of vital organs, heart and liver, where a large damage is life threatening for patients and any improvement in therapy would save many lives. Similar situation is in Graft versus host disease (GVHD), where MSCs immunomodulatory properties could be beneficial. Role of MSCs in heart regeneration was examined in vitro. Primary adult swine cardiomyocytes (CMCs) were co-cultured with or without swine MSCs for 3 days and morphological and functional parameters (contractions, current, respiration) of CMCs were measured. MSCs showed supportive effect on CMCs survival, especially at day 3 of the experiment, where in co-culture was significantly higher number of viable CMCs with physiological morphology and maintained function. Effect of MSCs on liver regeneration was observed in swine model of chronic liver...
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Stanovení exprese molekul transportu a metabolismu železa u vybraných chronických onemocnění. / Determining the expression of iron transport and metabolism molecules in chosen chronic diseases.

Chmelíková, Jitka January 2010 (has links)
Iron is an essential element for human organism, because it cooperates as a cofactor of enzymes in many metabolic pathways. Iron is a component of hemoglobin, and thus it is indispensable for the oxygen transport to tissues. It can exist as a ferrous or ferric form. However, ferrous iron paticipates in reactions in which highly reactive hydroxyl group can be formed. This product is harmful for the organism. Non-heme iron is taken up to the circulation through duodenal enterocyte. Iron excretion is carried out only by desquamation of the enterocytes or by bleeding. Therefore, iron intake must be strictly regulated. Iron overloading is observed in some chronic diseases (hereditary hemochromatosis, alcohol liver disease). In contrary, iron depletion can be a case of iron deficiency anemia. The aim of this master thesis is to determine the expression of iron transport molecules in duodenum in chronic diseases which originate due to disturbances of iron intake regulation. We determine the expression of molecules of iron transport (DMT1, Dcytb, ferroportin, hephaestin) on mRNA level by qPCR and on protein level by western blot. The level of serum hepcidin was determined by ELISA. Our results show an increased expression of mRNA of transporters DMT1 and ferroportin as well as ferrireductase Dcytb and ferroxidase...

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