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

Each year, approximately 795,000 people suffer a new or recurrent stroke. About 610,000 of these are first attacks, and 185,000 are recurrent attacks (Carandang et al. 2006). Currently the only FDA approved treatment for ischemic stroke is recombinant tissue plasminogen activator (Alteplase) (Marler and Goldstein 2003). Unfortunately its use is restricted to a short, 4.5 hour, time window. Two promising therapies in the treatment of stroke at delayed timepoints are human umbilical cord blood cells (HUCBC) and the sigma receptor agonist DTG The first series of experiments were conducted to characterize the effects of sigma receptors on various aspects of microglial activation. Sigma receptor activation suppresses the ability of microglia to rearrange their actin cytoskeleton, migrate, and release cytokines. Stimulation of sigma receptors suppressed both transient and sustained intracellular calcium elevations associated with microglial activation. Further experiments showed that sigma receptors suppress microglial activation by interfering with increases in intracellular calcium. An ex vivo organotypic slice culture (OTC) model to was utilized to characterize the efficacy of sigma receptor activation and HUCBC therapy in mitigating neurodegeneration in ischemic brain tissue in the absence of the peripheral immune system. HUCBC but not DTG treatment reduced the number of degenerating neurons and the production of microglia derived nitric oxide in slice cultures subjected to oxygen glucose deprivation (OGD) back to levels seen in the normoxia controls. The final experiments were performed to characterize the effects of the peripheral immune system on the brain over time and identify changes mediated by HUCBC and DTG. Labeled splenocytes were found in spleen, blood, and thymus, but not in the brain in appreciable numbers at any timepoint. IL10 and IFN?; levels were found to significantly increase by 96hours post MCAO. This increase in IL10 and IFNγ expression was blocked HUCBC or DTG. The experiments described here have shed light on the molecular mechanisms of stroke injury and the relative targets that DTG and HUCBC therapies exploit. These data suggest that the neuroprotection achieved by DTG or HUCBC is mediated by the ability of these treatments to modulate the peripheral immune systems response to injury.

Le foie et le poumon sont deux organes intimement liés et les atteintes pulmonaires sont fréquentes dans les pathologies hépatiques. En transplantation hépatique, les atteintes pulmonaires, les complications et la morbi-mortalité qu’elles engendrent, peuvent être en lien avec la pathologie hépatique du receveur mais aussi avec le donneur via le greffon, sa qualité et sa préservation. L’objectif de cette thèse était d’étudier deux aspects de cette interaction : 1- l’impact de l’insuffisance respiratoire aigüe (définie par le recours à la ventilation mécanique) sur le devenir post-transplantation ii) les conséquences des phénomènes d’ischémie-reperfusion du greffon hépatique sur les paramètres cardio-pulmonaires du receveur.Dans le premier travail, nous avons étudié, sur une cohorte de patients transplantés hépatiques à l’Hopital Henri Mondor (n=350 patients), le devenir post-opératoire en fonction de la présence ou non d’une ou plusieurs défaillances d’organe (neurologique, respiratoire, rénale, hémodynamique, hépatique et de la coagulation). Les patients avec au moins une défaillance d’organe ont une diminution significative de la survie post-LT à 90 jours (79% contre 96%) et 1 an (70% contre 91%) comparés aux patients cirrhotiques sans défaillance. Dans un deuxième travail issu de la même cohorte, nous développons un modèle permettant de prédire la mortalité à court terme et composé de 6 facteurs dont l’existence d’une défaillance d’organe. Le 3e travail, avec un effectif plus important (cohorte de l’Agence de la Biomédecine, PHRC « Optimatch »), a cherché à confirmer nos premiers résultats et à étudier le poids de chacune des défaillances d’organe et en particulier de la défaillance pulmonaire. Non seulement la présence d’une défaillance mais le nombre de défaillances au moment de la TH influence négativement le devenir à 3 mois des transplantés hépatiques. De plus, les défaillances pulmonaire et rénale sont des facteurs de risque indépendant de mortalité à 3 mois post-transplantation. Ces travaux montrent aussi que l’influence de ces défaillances d’organe peut être modulée en fonction du type de greffon, i.e. des critères du donneur.En plus de la qualité du greffon hépatique, la conservation de celui-ci a un impact sur la fonction du greffon et sur les paramètres cardio-pulmonaires chez le receveur. En effet dans un modèle de transplantation hépatique chez le gros animal (cochon), nous avons montré que les lésions d’ischémie/reperfusion du greffon engendrées entre le prélèvement et l’implantation ont des conséquences sur la fonction du greffon, le myocarde et le poumon. Ces lésions sont modulables selon la technique de préservation, notamment via l’utilisation de machine de perfusion.Ces travaux démontrent qu’au cours de la transplantation hépatique l’atteinte du parenchyme pulmonaire a un rôle clinique majeur chez le receveur et est médiée en partie par des phénomènes d’ischémie-reperfusion du greffon potentiellement modifiables par des améliorations des pratiques médicales. / Liver and lung are two closely related organs. In liver transplantation, lung damage, complications, morbidity and mortality can be related to the liver disease of the recipient but also to the donor via the graft, its quality and its preservation. The aim of this manuscript was to study two aspects of these interactions: 1- the impact of acute respiratory failure (defined by the use of mechanical ventilation) on the post-transplantation outcome ii) the consequences of the ischemia-reperfusion injury of the graft on cardiopulmonary parameters in the recipient.In the first study, we investigated the impact of one or more organ failure (cerebral, lungs, kidney, circulation, hepatic and coagulation) on the 90-day mortality post LT. Patients with at least one organ failure had a significant decrease in post LT survival at 90-day (79% versus 96%) and 1 year (70% versus 91%) compared with cirrhotic patients without failure. In a second study, from the same cohort, we developed a model to predict short-term mortality. This model is composed of 6 factors including the existence of organ failure. In the third study, with a largest cohort (Agence de Biomedicine, PHRC “Optimatch”), we have confirmed these first results and we observe that the number at the LT influences the outcome. Decision tree-modeling identified 6 subgroups further classified in 4 increasing risk classes, highlighting the prognostic importance of respiratory failure and renal failure at the LT as well as complex interactions between donor and recipient features.In addition to the quality of the graft, its preservation has an impact on the graft function and on the cardiopulmonary parameters in the recipient. Indeed, in a model of LT in the large animal (pig) we show that the ischemia / reperfusion injuries, generated between the sampling and the implantation, have consequences on graft function, myocardium and lung. These lesions could be subdued according to the preservation technique.These studies demonstrate that during LT the recipient's pulmonary complications and its morbidity are related to the recipient’s pre-existing hepatic disease and to the donor via the graft through ischemia-reperfusion phenomena of the graft.

Notre équipe s’intéresse à la relation structure-fonction d’une protéine, l’antithrombine (AT), un inhibiteur physiologique de la coagulation, en vue d’un développement thérapeutique. Cette protéine anticoagulante, capable de lier un motif pentasaccharidique sur les dérivés hépariniques, possède en outre, à fortes concentrations (500%), des propriétés anti-inflammatoires médiées par sa liaison aux héparan-sulfates cellulaires. Ce profil a mené à l’évaluation de l’AT dans des situations associant un emballement de la coagulation et de l’inflammation, comme c’est le cas au cours du sepsis sévère et d’autres situations d’ischémie-reperfusion (I/R). Cependant, les fortes concentrations utilisées dans les études précliniques nécessiteraient d’administrer des doses d’AT incompatibles avec le profil de sécurité de cette protéine anticoagulante.Dans ce contexte, nous avons, au cours de ce travail, caractérisé un variant d’AT (AT-N135Q-Pro394) dépourvu d’activité anticoagulante et doué d’une affinité augmentée pour l’héparine. Ce variant est capable de piéger des dérivés hépariniques et apparait comme un candidat idéal pour une utilisation comme antidote en cas de surdosage en héparine non fractionnée (HNF), héparines de bas poids moléculaire (HBPM) ou fondaparinux. Par ailleurs, ce variant pourrait être utilisé à des doses cytoprotectrices, sans risque hémorragique.Afin de tester cette dernière hypothèse, nous avons développé un modèle d’I/R rénale chez la souris, qui s’accompagne d’une augmentation significative de marqueurs de dysfonction rénale (Urée, Créatinine, Kim-1) et de l’inflammation (expression tissulaire de cxcl-1, il-6). L’AT avait déjà été montrée protectrice (Mizutani et al, Blood 2003) dans un modèle murin comparable. De façon surprenante, nous n’avons observé aucun des effets protecteurs décrits, ni sur l’inflammation ni sur la fonction rénale, et que ce soit avec de l’AT plasmatique, de l’AT recombinante ou encore avec un mélange équimolaire d’AT latente et native. Ce même modèle nous a pourtant permis de mettre en évidence les effets nephroprotecteurs et anti-inflammatoires d’une autre protéine anticoagulante, la protéine C activée. Ces résultats décevants font écho à la rétractation pour fraude de l’article de Mizutani et al. en 2013. Le travail approfondi que nous avons mené nous permet de clarifier la littérature et d’affirmer que l’AT, d’origine plasmatique ou recombinante, ne possèdent pas d’effet protecteur dans l’I/R rénale chez la souris. Dans ces conditions, le variant AT-N135Q-Pro394 n’a pas été testé.Concernant la seconde indication, l’AT-N135Q-Pro394 avait déjà été évaluée in vivo comme antidote aux dérivés hépariniques, HNF, HBPM et fondaparinux, avec d’excellents résultats. Néanmoins, cet effet antidote a été exploré spécifiquement par mesure de l’activité anti-facteur Xa alors que l’AT inhibe plusieurs enzymes de la cascade de coagulation tel que les facteurs VIIa, IXa et IIa. Nous avons donc exploré cet effet antidote dans un test plus global de la coagulation, le test de génération de thrombine (TGT) pour pouvoir le comparer aux autres stratégies non spécifiques utilisées pour antagoniser les dérivés hépariniques (facteur VII activé recombinant, concentré de complexes prothrombiques activés ou protamine). De façon intéressante, dans un plasma mimant un surdosage, notre variant présente un effet antidote supérieur aux agents hémostatiques et au sulfate de protamine vis-à-vis du fondaparinux et des HBPMs, respectivement, et équivalent au sulfate de protamine vis-à-vis de l’HNF. Enfin, dans du plasma en l’absence d’anticoagulant, l’AT-N135Q-Pro394 ne montre aucun effet sur la génération de thrombine contrairement aux agents hémostatiques et au sulfate de protamine qui, ajoutés seuls dans du plasma, modifient significativement le profil des TGT / Our team topic focuses on the structural-function relationship of a natural anticoagulant, antithrombin (AT), in order to develop potential therapeutic agents. AT inhibits several serine proteases of the coagulation cascade and its inhibitory activity is increased when AT binds to a pentasaccharidic motif contained within in the heparin derivatives. At high concentrations (500%), AT also exerts anti-inflammatory and cytoprotective properties through its binding to heparan sulfate proteoglycans, making it a good candidate for supportive therapy in clinical settings associating inflammation and coagulation activation. Indeed, AT has already been evaluated in vivo in various models of ischemia-reperfusion injury (IRI) and AT even reached a large-scale clinical trial in severe sepsis. However, the high concentrations of AT that are needed to exert anti-inflammatory properties are inconsistent with the safety profile of this anticoagulant protein.In this context we have further characterized an AT variant (AT-N135Q-Pro394) with increased affinity to heparin but devoid of anticoagulant activity. Indeed, this variant was described to be able to trap heparin derivatives and our work was to pursue the characterization of this variant as an antidote toward heparin derivatives in clinical situations of overdosing. In addition, this AT variant binds to heparan sulfate proteoglycans with higher affinity, as compared to native AT, and appears as a promising cytoprotective agent whose administration would not be associated with any bleeding risk.To test the latter hypothesis, we developed a murine model of renal IRI in which the renal function was severely impaired, as attested by increased kidney injury markers (urea, creatinine, kim-1) and local kidney inflammation (renal gene expression of il-6 and cxcl-1). Indeed, in 2003, Mizutani et al. reported a protective effect of AT in a similar murine model of renal IRI. Surprisingly, we observed none of the described protective effects, neither on inflammation nor renal function, with plasma AT, recombinant AT and an equimolar mixture of native and latent AT. Nevertheless, the same model enabled us to highlight the nephroprotective and anti-inflammatory properties of another anticoagulant protein, activated protein C (APC), as previously reported. These disappointing results coincided with the withdrawal in 2013 of the study of Mizutani et al., and our work allowed us to clarify the literature and to claim that neither recombinant nor plasma-derived native nor latent forms of AT exhibit a protective effect in renal IRI in mice. Under these conditions, AT-N135Q-Pro394 variant has not been tested in our model.AT-N135Q-Pro394 has also been previously shown to efficiently neutralise the anticoagulant activity of heparin derivatives, including unfractionated heparin (UFH), low molecular weight heparins (LMWH) and fondaparinux in vivo. Nevertheless, this reversal effect was only explored by anti-factor Xa assays whereas AT inhibits a number of coagulation proteases, including factors VIIa, IXa and IIa. Therefore, we explored AT-N135Q-Pro394 variant in a more global coagulation assay, the thrombin-generation assay (TGA), in order to compare its activity with non-specific reversal agents used toward heparin derivative overdose (recombinant-activated factor VII, activated prothrombin-complex concentrate or protamine). Interestingly, in plasma mimicking an overdose, our variant demonstrated greater reversal efficiency as compared to hemostatic agents and protamine sulfate toward fondaparinux and LMWH, respectively, and was as efficient as protamine sulfate toward UFH. Finally, when added to native plasma (in the absence of heparin derivative), AT-N135Q-Pro394 showed no effect on thrombin generation unlike hemostatics and protamine sulfate that all significantly affect the TGA profile

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22362号 / 医博第4603号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 平井 豊博, 教授 稲垣 暢也, 教授 竹内 理 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22696号 / 医博第4640号 / 新制||医||1045(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 羽賀 博典, 教授 妹尾 浩, 教授 木村 剛 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23055号 / 医博第4682号 / 新制||医||1048(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 妹尾 浩, 教授 伊達 洋至, 教授 長船 健二 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23072号 / 医博第4699号 / 新制||医||1049(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川口 義弥, 教授 浅野 雅秀, 教授 福田 和彦 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23107号 / 医博第4734号 / 新制||医||1051(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 平井 豊博, 教授 湊谷 謙司, 教授 川口 義弥 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Peripheral arterial occlusive disease (PAOD) is a globally-prevalent cardiovascular disease in which atherosclerotic plaques narrow arterial lumen diameters and restrict blood flow to downstream tissues. The impact of these occlusions can be mitigated by collateral vessels that connect parallel arterial branches and act as natural bypasses to maintain perfusion. In animal models that lack collateral arterioles, capillaries that connect terminal arteriolar segments can arterialize and form functional collaterals following an ischemic event; however, in the early stages of development, vasodilation is impaired. We explored the mechanism of impaired vasodilation in arterialized collateral capillaries (ACCs) and pre-existing collaterals (PECs) by evaluating endothelial-dependent vasodilation and endothelial-independent reactivity at day seven following the ischemic event. We also evaluated functional vasodilation in mature ACCs and PECs at day 21 by applying vasodilation inhibitors during the electrical stimulation of muscle contraction. Arterial occlusion was performed by ligating the cranial-lateral spinotrapezius feed artery in Balb/C mice, a strain that either lacks native arteriolar collaterals or contains a single collateral arteriole (~50% of mice), as opposed to the C57Bl/6 strain, which each contain 10 or more collateral arterioles. At seven days post-surgery, both vasodilation and vasoconstriction were impaired in ACCs when compared to terminal arterioles of similar size in unoperated limbs, but still exhibited significant changes when compared to baseline. The comparable reactivity in both endothelial-dependent and independent vasodilation at day-seven in ACCs indicates that vascular smooth muscle cells are likely responsible for the impairment, as they may still be developing, rearranging, or both, and are not yet fully capable of regulating diameter in immature ACCs. However, by 21 days post-ligation, ACCs regained the capacity to dilate in response to muscle contraction, and utilized similar vasodilation pathways as control vessels. At seven days post-ligation, PECs had impaired endothelialindependent dilation, but successful endothelial-dependent dilation, indicating the use of alternative pathways to dilate. Unlike ACCs, the PECs never completely restored vasodilation capabilities by day 21, which may be due to a variation in smooth muscle phenotype, sensitivity to vasoactive agents, and/or limited growth factor expression. For future work, evaluating collateral formation and vasodilation in a diseased model and investigating molecular variations in the smooth muscle may yield additional knowledge that can improve therapies for patients during ischemic events.