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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.
11

Hepatocellular carcinoma in a woman with 34 weeks gestation and chronic hepatitis b / Carcinoma hepatocelular en una mujer con 34 semanas de gestación y hepatitis b crónica

Sato-Espinoza, Karina, Ferrer, Javier Díaz, Ventura, Yessica Mitzy Jaramillo 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / A 24-year-old pregnant woman arrived at the emergency service at 34 weeks of gestational age with intermittent right upper abdominal pain. An abdominal ultrasound was performed showing signs of hepatopathy with multiple neo-formative nodules with mild ascites and fetal biometry confirmed at 34 weeks gestation. During her hospitalization, an emergency caesarean was induced with favorable result in the survival of the mother and the baby. / Revisión por pares
12

Anti-Tumorigenic and Immunomodulatory Effects of Ibrutinib Against Hepatocellular Carcinoma

Elkholy, Khadija Hassan 23 October 2017 (has links)
No description available.
13

Targeting amplicon and tumor suppressor loci in primary hepatocellular carcinoma.

January 2002 (has links)
Li Ching-wan. / Thesis submitted in: November 2001. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 104-130). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACTS (ENGLISH/CHINESE) --- p.iii / LIST OF FIGURES --- p.xi / LIST OF TABLES --- p.xiii / LIST OF ABBREVIATIONS --- p.xiv / Chapter CHAPTER1 --- INTRODUCTION / Chapter 1.1. --- Liver Cancer --- p.1 / Chapter 1.2. --- Hepatocellular Carcinoma --- p.1 / Chapter 1.2.1. --- Types of Liver Cancer --- p.1 / Chapter 1.2.2. --- Epidemiology --- p.4 / Chapter 1.2.2.1. --- Geographical Distribution --- p.4 / Chapter 1.2.2.2. --- Age and Gender Distribution --- p.8 / Chapter 1.2.3. --- Etiologic Factors --- p.9 / Chapter 1.2.3.1. --- Chronic Infection with Hepatitis B (HBV) and C (HCV) Viruses --- p.9 / Chapter 1.2.3.2. --- Aflatoxin B1 --- p.11 / Chapter 1.2.3.3. --- Alcohol --- p.12 / Chapter 1.2.3.4. --- Summary --- p.12 / Chapter 1.3. --- HCC in Hong Kong --- p.14 / Chapter 1.4. --- Role of Viral Hepatitis B in HCC --- p.17 / Chapter 1.4.1. --- HBV Genome --- p.17 / Chapter 1.4.2. --- Consequences of HBV DNA Integration --- p.17 / Chapter 1.4.2.1. --- HBV Integration --- p.17 / Chapter 1.4.2.2. --- Transactivation of Cellular Genes by HBV DNA --- p.19 / Chapter 1.4.2.3. --- Chromosomal DNA Instability --- p.20 / Chapter 1.5. --- Genetic Alterations in HCC --- p.21 / Chapter 1.5.1. --- Tumor Suppressor Gene --- p.21 / Chapter 1.5.2. --- Proto-oncogene --- p.23 / Chapter 1.5.3. --- Genetic Studies in HCC --- p.23 / Chapter 1.5.3.1. --- Loss of Heterozygosity (LOH) --- p.25 / Chapter 1.5.3.2. --- Comparative Genomic Hybridization (CGH) --- p.26 / Chapter 1.5.3.3. --- Array CGH --- p.26 / Chapter 1.5.4. --- Large-Scale Genetic Analysis in HCC --- p.27 / Chapter CHAPTER2 --- RATIONALE IN THIS STUDY --- p.35 / Chapter CHAPTER3 --- MATERIALS AND METHODS / Chapter 3.1. --- Patients and Materials --- p.38 / Chapter 3.1.1. --- DNA Extraction --- p.40 / Chapter 3.2. --- Loss of Heterozygosity Analysis on Chromosome 4q --- p.40 / Chapter 3.2.1. --- Microsatellite Markers --- p.41 / Chapter 3.2.2. --- Amplification of Target Sequences by PCR --- p.42 / Chapter 3.2.2.1. --- 5-end Labeling Primers --- p.42 / Chapter 3.2.2.2. --- Amplification of Target Sequences --- p.42 / Chapter 3.2.3. --- Denaturing Polyacrylamide Gel --- p.44 / Chapter 3.2.3.1. --- Electrophoresis --- p.44 / Chapter 3.2.4. --- Detection of Loss of Heterozygosity (LOH) --- p.45 / Chapter 3.2.5. --- Duplex PCR Analysis of Homozygous Deletion --- p.45 / Chapter 3.3. --- Amplification Analysis by Array-CGH --- p.46 / Chapter 3.3.1. --- Nick-Translation --- p.49 / Chapter 3.3.2. --- Hybridization --- p.49 / Chapter 3.3.3. --- Imaging and Data Analysis --- p.50 / Chapter 3.3.4. --- Determination of Normal Range for All Cases --- p.51 / Chapter 3.3.5. --- Assessment of Data Quality --- p.51 / Chapter 3.4. --- Statistical Analysis --- p.52 / Chapter CHAPTER4 --- RESULTS / Chapter 4.1. --- Loss of Heterozygosity Analysis on Chromosome 4q --- p.53 / Chapter 4.1.1. --- Region I of Smallest Common Deletion Region --- p.54 / Chapter 4.1.2. --- Region II of Smallest Common Deletion Region --- p.54 / Chapter 4.2. --- Amplification Analysis by Array-CGH --- p.62 / Chapter CHAPTER5 --- DISCUSSION / Chapter 5.1. --- LOH Analysis on Chromosome 4q --- p.73 / Chapter 5.1.1. --- LOH of Chromosome 4q in Various Cancers --- p.74 / Chapter 5.1.1.1. --- Hepatocellular Carcinomas --- p.74 / Chapter 5.1.1.2. --- Other Neoplasia --- p.76 / Chapter 5.1.2. --- Functional Studies on Chromosome 4 --- p.76 / Chapter 5.1.3. --- Putative Tumor Suppressors on Chromosome 4q --- p.80 / Chapter 5.1.3.1. --- Region I (4q27-q28.1) --- p.80 / Chapter 5.1.3.1.1. --- MAD2L1 (4q27) --- p.80 / Chapter 5.1.3.2. --- Region II (4q35.2) --- p.81 / Chapter 5.1.3.2.1. --- INGlL(4q35.1) --- p.81 / Chapter 5.1.3.2.2. --- FAT (4q34-q35) --- p.81 / Chapter 5.1.3.2.3. --- Caspase 3 (4q35) --- p.82 / Chapter 5.1.4. --- Limitation of this Study --- p.83 / Chapter 5.1.4.1. --- Markers --- p.83 / Chapter 5.1.4.1.1. --- Limitation of the Markers --- p.83 / Chapter 5.1.4.1.2. --- Location of the Microsatellite Markers --- p.83 / Chapter 5.1.4.2. --- Tissue Samples --- p.84 / Chapter 5.1.4.2.1. --- Normal Reference --- p.84 / Chapter 5.1.4.2.2. --- Pathologic Characterization --- p.85 / Chapter 5.1.5. --- Future Studies --- p.85 / Chapter 5.1.5.1. --- Improvement of the Experiment --- p.85 / Chapter 5.1.5.2. --- Extension of the Present Study --- p.86 / Chapter 5.2. --- Amplification Analysis by Array-CGH --- p.88 / Chapter 5.2.1. --- Amplicons Showing Amplification in HCC --- p.89 / Chapter 5.2.1.1. --- Locus of 17q23 --- p.89 / Chapter 5.2.1.1.1. --- D17S1670 --- p.89 / Chapter 5.2.1.1.2. --- RPS6KB1 --- p.91 / Chapter 5.2.1.2. --- Locus of 1q25-q31 --- p.92 / Chapter 5.2.1.2.1. --- LAMC2 --- p.92 / Chapter 5.2.1.3. --- Locus of 3q26.3 --- p.93 / Chapter 5.2.1.3.1. --- PIK3CA --- p.93 / Chapter 5.2.1.4. --- Locus of 8p22 --- p.94 / Chapter 5.2.1.4.1. --- CTSB --- p.94 / Chapter 5.2.1.5. --- Locus of 6q22 --- p.95 / Chapter 5.2.1.5.1. --- MYB --- p.95 / Chapter 5.2.1.6. --- Locus of 20ql3 --- p.96 / Chapter 5.2.1.6.1. --- CSE1L --- p.96 / Chapter 5.2.1.7. --- Locus of Ip36.2-p35.1 --- p.97 / Chapter 5.2.1.7.1. --- FGR --- p.97 / Chapter 5.2.1.8. --- Locus of 7q21.1 --- p.98 / Chapter 5.2.1.8.1. --- PGY1 --- p.98 / Chapter 5.2.2. --- Amplicons Showing Deletion in HCC --- p.99 / Chapter 5.2.2.1. --- Loss at 11ql3 and 14q32.3 --- p.99 / Chapter 5.2.3. --- Limitation of the Study --- p.100 / Chapter 5.2.3.1. --- Samples and Materials --- p.100 / Chapter 5.2.4. --- Further Study --- p.101 / Chapter 5.2.4.1. --- Confirmation of the Result in Various Levels --- p.101 / Chapter 5.2.4.2. --- Assessment of the Significant Losses on Chromosomes 11ql3 and 14ql3 --- p.101 / Chapter 5.2.5. --- Application of Microarray in Genetic Studies --- p.102 / Chapter 5.2.5.1. --- Deletion Analysis --- p.102 / Chapter 5.2.5.2 --- Tissue Microarray --- p.103 / Chapter 5.2.5.3. --- cDNA Microarray --- p.103 / Chapter chapter6 --- references --- p.104
14

Lebertransplantation bei Patienten mit hepatozellulärem Karzinom. Eine retrospektive Studie am Universitätsklinikum Leipzig im Zeitraum von 1994 bis 2010. Charakterisierung des Patientenkollektivs und Analyse von Einflussfaktoren auf Überleben und Outcome.

Kienlein, Andreas 05 July 2016 (has links) (PDF)
Für Lebertransplantationen bei Patienten mit hepatozellulärem Karzinom stellt sich angesichts der defizitären Organspendesituation die berechtigte Frage, unter welchen Bedingungen diese Form der Therapie ein gutes Outcome für die Patienten verspricht und somit keine Verschwendung der ohnehin knappen Ressourcen darstellt. Ziel dieser Arbeit war es, ein Kollektiv aus 98 Patienten, die an einem hepatozellulären Karzinom erkrankten und im Zeitraum von 1994 bis einschließlich 2010 am Universitätsklinikum Leipzig eine Lebertransplantation erhielten, retrospektiv zu charakterisieren und den Einfluss mehrerer Faktoren auf das Outcome der Patienten zu untersuchen. Bei den Faktoren handelte es sich um die Wartezeit, den präoperativen Einsatz der TACE, den präoperativen AFP-Serumspiegel, sowie die Tumorzahl und -größe. Der Nachbeobachtungszeitraum lag bei 3 Jahren. Die Charakterisierung des Kollektivs erbrachte folgende Ergebnisse: Das Kollektiv bestand zu rund 80% aus Männern. Das mediane Alter zum Zeitpunkt der Transplantation lag bei 59 Jahren. Die Transplantationszahlen bei HCC-Patienten sind am UKL seit Einführung des MELD-Scores 2006 deutlich angestiegen. Die mediane Wartezeit hat sich seit Einführung des MELD-Scores nicht wesentlich verändert. Sie betrug 7,3 Monate in der Prä-MELD-Ära und 6,9 Monate in der MELD-Ära. Mit über 60% war der Alkoholabusus die häufigste Ursache für die Entstehung des hepatozellulären Karzinoms. An zweiter Stelle stand die Hepatitis-C-Infektion. In der Diagnostik des HCC spielte die Computertomographie die größte Rolle. Die Sensitivität des AFP zur Erfassung des HCC (>400 ng/ml) war mit Werten unter 30% sehr niedrig. Die TACE war die mit Abstand am häufigsten durchgeführte, neoadjuvante Maßnahme. Zum Zeitpunkt der Transplantation befanden sich rund 75% der Patienten in einem Stadium bis maximal T2. Das Auftreten von solitären und multifokalen HCCs war in etwa gleich häufig (46,9% vs. 53,1%). Die Milan-Kriterien waren bei knapp 39% der Patienten im postoperativen Explantat-Befund überschritten. Nach Transplantation traten bei 26 Patienten Abstoßungsreaktionen auf. 8 Patienten mussten aufgrund eines Transplantatversagens retransplantiert werden. Das postoperative Überleben (intention-to-treat) betrug 75,5% (6 Monate), 71,4% (1 Jahr) und 63,3% (3 Jahre). Die entsprechenden Rezidivraten lagen bei 11,2%, 14,3% und 22,4%. Rezidiven traten am häufigsten in der Spenderleber auf, gefolgt von einem Befall der Lymphknoten und Knochen. Ein signifikanter Einfluss auf das Outcome der Patienten konnte für das AFP, die Tumorzahl und die Milan-Kriterien nachgewiesen werden: Präoperative AFP-Spiegel unter 100 ng/ml zeigten eine signifikant niedrigere Rezidivrate. Multifokale Tumoren waren mit einem signifikant schlechteren 3-Jahres-Überleben verknüpft. Bei Erfüllung der Milan-Kriterien (im postoperativen Explantat-Befund) war die Rezidivrate signifikant und die Überlebensrate deutlich besser. Für die Wartezeit konnte seit Einführung des MELD-Scores eine positive Entwicklung festgestellt werden. Das 3-Jahresüberleben hat sich bei Wartezeiten unter 12 Monaten um 22,5% verbessert. Die Rezidivrate ist bei Wartezeiten über 12 Monate um 15,3% gesunken. Für den Einfluss der TACE auf das Outcome der Patienten konnten keine signifikanten Unterschiede festgestellt werden. Auch andere Studien belegten bisher lediglich einen Vorteil für das erfolgreiche Downstaging gegenüber Patienten, bei denen die TACE erfolglos blieb. Für die Untersuchung des tatsächlichen Nutzens einer TACE vor Transplantation werden daher Studien mit höherem Evidenzgrad benötigt.
15

HLA expression in hepatocellular carcinoma cell lines.

Coplan, Keren Anne January 1992 (has links)
Being a dissertation presented in fulfilment of the requirements governing the degree of Masters of Science in the Faoulty of Medicine, University of the Witwatersrand / Recent investigations have shown enhanced or aberrant expression of major histocompatibility system (MHC) antigens on cells lines derived from human hepatocellular carcinoma (HCC) in vitro and HCC in vivo. ( Abbreviation abstract ) / AC2017
16

Functional characterization of sirtuin 1 (SIRT1) in hepatocellular carcinoma. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Chen, Juan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 124-154). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
17

Nephrogenous cyclic adenosine monophosphate in primary hepatocellular carcinoma.

January 1990 (has links)
by Kam-Ming Au. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 87-101. / LIST OF TABLES / LIST OF FIGURES / ACKNOWLEDGEMENTS / ABSTRACT / Chapter CHAPTER 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Normal calcium homeostasis --- p.1 / Chapter 1.2 --- The incidence and common causes of hypercalcemia in hospital population --- p.6 / Chapter 1.3 --- Hypercalcemia in primary hyperparathyroidism --- p.10 / Chapter 1.4 --- Hypercalcemia of malignancy --- p.13 / Chapter 1.5 --- Pathophysiology of humoral hypercalcemia of malignancy --- p.16 / Chapter 1.6 --- Pathogenesis of humoral hypercalcemia of malignancy-evidence for a parathyroid hormone-related peptide --- p.20 / Chapter 1.7 --- Hypercalcemia in primary hepatocellular carcinoma --- p.27 / Chapter 1.8 --- Physiological role of cyclic adenosine monophosphate --- p.28 / Chapter 1.9 --- Aim of the present study --- p.29 / Chapter CHAPTER 2. --- MATERIALS AND METHODS --- p.30 / Chapter 2.1 --- Patients --- p.30 / Chapter 2.1.1 --- Hepatocellular carcinoma patients --- p.30 / Chapter 2.1.2 --- Cirrhotic patients --- p.30 / Chapter 2.2 --- Healthy control subjects --- p.30 / Chapter 2.3 --- Collection of blood and urine specimens --- p.32 / Chapter 2.4 --- Methods --- p.32 / Chapter 2.4.1 --- Routine chemistries --- p.32 / Chapter 2.4.2 --- Plasma and urine cyclic adenosine monophosphate --- p.33 / Chapter - --- commercial urine controls --- p.34 / Chapter - --- scintillation cocktail --- p.34 / Chapter - --- imprecision study --- p.34 / Chapter - --- accuracy study --- p.34 / Chapter 2.4.3 --- Nephrogenous cyclic adenosine monophosphate and total urinary cyclic adenosine monophosphate / 100 ml glomerular filtrate --- p.35 / Chapter 2.4.4 --- Total urinary cyclic adenosine monophosphate : creatinine ratio --- p.36 / Chapter 2.4.5 --- Components of hypercalcemia --- p.36 / Chapter 2.4.6 --- Urinary hydroxyproline : creatinine ratio --- p.37 / Chapter 2.4.7 --- Renal phosphate threshold --- p.37 / Chapter 2.4.8 --- Serum parathyroid hormone --- p.38 / Chapter 2.4.9 --- Serum parathyroid hormone-related peptide --- p.38 / Chapter 2.5 --- Statistical analysis --- p.39 / Chapter CHAPTER 3. --- RESULTS --- p.40 / Chapter 3.1 --- Method validation for cyclic adenosine monophosphate assay --- p.40 / Chapter 3.1.1 --- Standard curve of the cyclic adenosine monophosphate assay --- p.40 / Chapter 3.1.2 --- Results of imprecision study --- p.43 / Chapter 3.1.3 --- Results of accuracy study --- p.43 / Chapter 3.2 --- "Results of hypercalcemic and normocalcemic hepatocellular carcinoma patients, cirrhotic patients, and healthy control subjects" --- p.47 / Chapter 3.2.1 --- "Results of serum calcium, albumin adjusted calcium, serum albumin and serum alkaline phosphatase" --- p.47 / Chapter 3.2.2 --- "Results of serum phosphate, renal phosphate threshold and serum parathyroid hormone" --- p.51 / Chapter 3.2.3 --- Results of plasma cyclic adenosine monophosphate --- p.55 / Chapter 3.2.4 --- "Results of nephrogenous cyclic adenosine monophosphate , total urinary cyclic adenosine monophosphate / 100 ml glomerular filtrate and total urinary cyclic adenosine monophosphate : creatinine ratio 59" / Chapter 3.2.5 --- Results of urinary calcium : creatinine ratio and urinary hydroxyproline : creatinine ratio --- p.66 / Chapter 3.2.6 --- Factors contributing to hypercalcemia in hepatocellular carcinoma patients 71 / Chapter 3.2.7 --- Results of serum parathyroid hormone-related peptide --- p.75 / Chapter CHAPTER 4. --- DISCUSSION --- p.77 / REFERENCES --- p.87
18

Comparison of linear, bi-dimensional, and volumetric measurements in evaluating tumor response of hepatocellular carcinoma lesions in the arterial and portal venous phases on MRI

Pratt, Michelle Sherman 12 March 2016 (has links)
There are unmet needs in evaluating treatment response of hepatocellular carcinoma in research protocols. Early predictors, such as imaging biomarkers, could allow for earlier judgment of treatment effect. Currently RECIST is the most widely accepted criterion in clinical trials. A modified RECIST (mRECIST) criterion was developed to take into account the unique imaging characteristics of HCC lesions. Much discussion has occurred regarding linear measurements and their appropriateness for evaluating change in tumor burden over time. The simplicity of currently accepted criteria differs with the increasing sophistication of imaging techniques. Tumor volume change on 3D imaging can provide insight into actual action of treatment rather than an estimate of action as shown by linear and bi-dimensional measurements. It was the aim of this study to determine whether linear, bi-dimensional, and volumetric percent changes of HCC lesions, in both the arterial and portal venous phases, are significantly comparable. 27 HCC lesions (identified on 25 subjects) were measured at two timepoints by each method on 3D GRE MRI scans in both phases. Percent change was calculated per lesion for each measurement type in both the arterial and portal venous phases. Signed rank tests, paired t tests, and comparison of change tests were run to evaluate the data. Significant differences between the percent changes of linear measurements versus volumetric measurements were observed using a Wilcoxon signed-rank test which showed p = 0.0000. A simple correlation assessment showed positive correlations for all measurements, with the lowest being correlations 0.8679 for the arterial linear percent change versus the arterial volumetric percent change and 0.8434 for the portal venous linear percent change versus the portal venous volumetric percent change. Differences between percent changes of linear versus bi-dimensional measurements and bi-dimensional versus volumetric measurements were significant as well (Linear versus bi-dimensional p = 0.0001, bi-dimensional versus volumetric p = 0.0004). To conclude, the differences in the percent changes when comparing the measurement types are statistically significant, particularly when comparing linear and volumetric measurements. Establishing a reproducible volumetric criterion could lead to improvements in the implementation of clinical trials.
19

Les mécanismes de réponse à l'inflammation chronique dans le foie stéatosique et les conséquences sur l'homéostasie cellulaire et la cancérogénèse / Response mechanisms to chronic inflammation in steatotic liver and consequences on cellular homeostasy and carcinogenesis

Degli Esposti, Davide 15 June 2011 (has links)
Le foie est un organe essentiel à la vie chez tous les mammifères. C’est un organe central du métabolisme énergétique et de la détoxification des substances xénobiotiques auxquelles l’individu est exposé. Le foie est la cible d’agressions diverses, telles que les virus, l’alcool, les substances chimiques présentes dans l’alimentation ou l’environnement. Il peut également subir destransformations pathologiques profondes, lors du diabète ou de l’obésité par exemple.La stéatose hépatique, caractérisée par une accumulation de triglycérides sous forme de vésiculesgénérant une réponse inflammatoire, est connue depuis de nombreuses années. Son étude a permisde définir un modèle en deux étapes (« two hits ») indispensables à la genèse d’une stéatohépatite ou NASH. La première est l’accumulation de lipides, la seconde consiste en la genèse d’un stress oxydant et la libération de cytokines. La NASH est une des conséquences pathologiques du syndrome métabolique au cours duquel une résistance des tissus à l’insuline se développe.Récemment, la composition des lipides accumulés dans la NASH a été décrite et montre la présence de cholestérol libre et de différents métabolites des acides gras dont la toxicité est grande mais variable. De façon surprenante, une nouvelle hypothèse tend à émerger quant aux rôles protecteurs de certaines catégories de lipides. En effet, le stockage des triglycérides sous forme de vésicules pourrait être un mécanisme de survie cellulaire (Neuschwander-Tetri, 2010). Il s’agirait principalement d’une tolérance à la mort cellulaire par nécrose ou apoptose. Dans ce contexte,l’activation de l’autophagie serait capitale et la nécrose ne serait plus un mécanisme non contrôlé,mais au contraire un système finement régulé.Des données expérimentales récentes suggèrent l’existence d’un réseau complexe d’interactions moléculaires qui lient, dans la NASH comme dans le cas de la cancérogenèse, le métabolisme énergétique, la réponse inflammatoire systémique et tissulaire et des altérations subcellulaires, telles que les lésions des mitochondries et du réticulum endoplasmique.Nous avons utilisé le cas particulier du préconditionnement ischémique, une technique chirurgicale qui consiste, grâce à de courtes périodes d’occlusion vasculaire avant l’ischémie, à conférer au tissu une protection contre les lésions d’ischémie/reperfusion (I/R), pour étudier les mécanismes de survie mis en place par les hépatocytes stéatosiques au cours d’un stress d’I/R. Dans deux contextes différents, celui d’une ischémie chaude au cours d’une hépatectomie partielle et celui d’une ischémie froide au cours de la transplantation hépatique, nous avons montré que l’autophagie peut jouer un rôle central dans la protection des hépatocytes stéatosiques. Cependant, il est envisageable qu’un dysfonctionnement de l’autophagie pourrait conduire à la genèse d’altérations cellulaires comme une instabilité génomique, caractéristique de la transformation cancéreuse. L’équilibre entre la survie et la mort cellulaire dépend donc de l’intégration de cette signalisation complexe, qui concerne l’état énergétique de la cellule, la réponse aux stress transitoires et l’adaptation aux stress chroniques. Dans ce contexte, l’autophagie semble jouer un rôle central dans l’intégration de la réponse aux stress (Kroemer et al 2010), ce qui pourrait favoriser directement ou indirectement la transformation cancéreuse d’une cellule.L’amélioration de la compréhension des mécanismes impliqués dans la tolérance et la survie des hépatocytes chargés de lipides en réponse à un stress inflammatoire, ischémique ou du réticulum endoplasmique semble donc essentielle. Elle permettrait en effet la mise en place de nouvelles stratégies thérapeutiques qui pourraient améliorer la prise en charge des patients, augmenter le nombre de greffons disponibles pour les greffes, et la prévention des risques cancérogènes pour le foie. / Liver is a an essential to life organ in all mammals. It plays a central role in energy and drug metabolism. Liver is constantly challenged by damaging compounds such as viruses, alcohol and chemicals from food intake or from the environment. It can also undergo some deep pathological transformations, e.g. in diabetes or obesity. Liver steatosis has been known for many years, it is defined as an accumulation of triglycerides vesicles generating an inflammatory response in hepatocytes. A « two step hypothesis » has been proposed for the genesis of Non Alcoholic Steatohepatitis (NASH). The first step is the fat accumulation, the second step involves the generation of an oxidative stress and the release ofcytokines. NASH is one of the pathological consequences of metabolic syndrome, when insulin resistance occurs in the tissues.The composition of accumulated fat in NASH has been recently described and reveals the presence of free cholesterol and different fatty acids metabolites with a high but variable toxicity. Surprisingly, a new hypothesis tends to emerge about the protective effects of some types of lipides.Triglyceride storage in vesicles could indeed be a survival mechanism for cells (Neuschwander-Tetri, 2010). It is assumed that it would mainly result in an tolerance to cell death by necrosis orapoptosis. In this context, (activation of) autophagy would play a key-role and necrosis, usually an uncontrolled mechanism, would become accurately regulated. Similarly to oncogenesis, recent experimental data in NASH suggest that energy metabolism,systemic and tissular inflammatory response and subcellular alterations such as impaired mitochondria and ER are connected in a complex network of molecular interactions. Ischemic preconditioning (IP) is a surgical technique consisting of brief periods of vascular occlusion which confer protection against subsequent ischemia/reperfusion via endogenous protective mechanisms. We investigated the survival mechanisms set up by steatotic hepatocytes during I/R, with or without IP. In the following two situations, warm ischemia during partial hepatectomy and cold ischemia during liver transplantation, we pointed out that autophagy can play a central role in steatotic hepatocytes protection. However, an autophagy dysfunction might result in the generation of cellular impairments such as genomic instabilities, typical features of oncogenic transformation. Therefore, the balance between cell survival or death depends on the integration of a complex signaling, taking into account the cellular energetic state, the cell response to transient stress and its adaptation to chronical stress. In that context, autophagy seems to play a central role in the integration of stress response (Kroemer et al Mol Cell 2010), which could promote, directly or indirectly the malignant cell transformation.Therefore, it seems essential to improve the understanding of mechanisms involved in tolerance and survival of lipid-full hepatocytes in response to an inflammatory, ischemic or ER stress. Indeed, this would help developing new therapeutical strategies to improve patients care, increase the number of available grafts for transplants, and prevent cancer risks in liver.
20

Eicosapentaenoic acid (EPA) induced apoptosis in human hepatoma cells through p53 pathway. / CUHK electronic theses & dissertations collection

January 2002 (has links)
Chi Tian-yi. / "July 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 213-257). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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