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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

Estudo piloto do impacto da terapia antiproliferativa com everolimus administrado por via oral na diminuição de reestenose após implante de stent auto-expansível de nitinol para tratamento de lesões oclusivas da artéria femoral superficial / Pilot study of the impact of antiproliferative therapy with everolimus administered orally in the reduction of restenosis after implantation of selfexpandable nitinol stent for treatment of occlusive lesions of the superficial femoral artery

Luis Ramon Virgen Carrillo 15 June 2009 (has links)
INTRODUÇÃO: A implantação de stent auto-expansível de nitinol para o tratamento das lesões oclusivas femoro-poplíteas tem sido associado com maus resultados a longo prazo. O everolimus administrado via oral para inibir reestenoses do stent foi investigado recentemente em animais com bons resultados, porém sua segurança e eficácia não têm sido estudada em seres humanos. O propósito deste estudo piloto foi avaliar o impacto da terapia antiproliferativa com everolimus administrado via oral por 28 dias na diminuição de reestenose após implante de stent auto-expansível de nitinol para tratamento de lesões oclusivas da artéria femoral superficial. MÉTODOS E RESULTADOS: Trinta e quatro pacientes foram recrutados para este estudo randomizado, prospectivo. O grupo que recebeu everolimus via oral foi constituído por 15 pacientes e o grupo que não recebeu medicação composto por 19 pacientes. As características basais e do procedimento foram similares entre os dois grupos. Todos os pacientes tinham isquemia crônica do membro inferior e oclusão da artéria femoral superficial (média da lesão de 83,14 mm no grupo sem medicação e 105 mm no grupo everolimus). O objetivo primário do estudo foi a redução da porcentagem média do diâmetro da reestenose intra-stent após seis meses da angioplastia avaliada por angiografia quantitativa. A porcentagem média do diâmetro das reestenoses foi 46,9% no grupo tratado com everolimus e 44,5% no grupo que não recebeu a medicação (p=0,81). Não foram observados efeitos colaterais graves nos grupos. No acompanhamento clínico aos 24 meses não houve diferenças significativas entre os grupos em relação a eventos clínicos. A patência primária, primária assistida e secundária em 24 meses, foi 42%, 74% e 79% no grupo sem medicação e 27%, 73% e 73% no grupo tratado com everolimus. CONCLUSÃO: O everolimus via oral por 28 dias em doses altas é seguro e bem tolerado, com baixo índice de efeitos colaterais, porém não é eficaz na redução da porcentagem média do diâmetro da reestenose intra-stent em pacientes com implante de stents auto-expansíveis de nitinol nas lesões oclusivas complexas da artéria femoral superficial. / INTRODUCTION: The implantation of a self-expanding of nitinol stent in the treatment of femoropopliteal occlusive lesions has been associated with a poor outcome in a long term setting. Everolimus administered orally to inhibit restenosis of the stent was investigated recently in animals with good results, but its safety and efficacy has not been studied in humans. The purpose of this pilot study was to evaluate the impact of antiproliferative therapy with everolimus administered orally for 28 days in the reduction of restenosis after implantation of self-expandable nitinol stent for treatment of occlusive lesions of the superficial femoral artery. METHODS AND RESULTS: Thirty-four patients were recruited for this randomized, prospective study. The group that received oral Everolimus was consisted of 15 patients and the group that received no medication was 19 patients. The baseline characteristics and procedure were similar in both groups. All the patients had chronic lower limb ischemia and occlusion of the superficial femoral artery (mean of the lesion of 83.14 mm in the group without medication and 105 mm in the everolimus group). The primary objective of the study was to evaluate the reduction of the average percentage of the diameter of in-stent restenosis six months after angioplasty assessed by quantitative angiography. The in-stent mean percent diameter stenosis was 46.9% in the group treated with everolimus and 44.5% in the group that received no medication (p = 0.81). There were no serious side effects seen in either group in the clinical follow up at 24 months. There was no significant difference between groups in relation to clinical events. The primary patency, assisted primary and secondary in 24 months was 42%, 74% and 79% in the group without medication and 27%, 73% and 73% in the group treated with Everolimus. CONCLUSION: Everolimus administered orally for 28 consecutive days to stent implantation in high doses proves to be safe and well tolerated, with low rate of side effects, but it is not effective in reducing the average percentage of diameter of in-stent restenosis in patients with implantation of self-expandable nitinol stent in complex occlusive lesions of the superficial femoral artery.
12

Dysfonctions vasculaire et musculaire, aiguë et chronique. Quelle place pour la modulation pharmacologique du stress oxydant ? / Vascular and muscular dysfunctions in acute and chronic injury models. What is the place for a pharmacological modulation of oxidative stress?

Kremer, Hélène 21 September 2012 (has links)
Le but de notre travail était l’étude des dysfonctions artérielle et musculaire dans des modèles d’agression aiguë et chronique puis l’évaluation de l’effet de la modulation pharmacologique du stress oxydant sur les anomalies vasculaires induites. Dans le modèle aigu de choc endotoxinique chez la souris, l’administration d’albumine humaine a permis d’augmenter leur survie, d’améliorer l’hyporéactivité vasculaire et la dysfonction endothéliale grâce à des propriétés ,concentration-dépendante, anti-oxydantes, modulatrices de l’inflammation, aboutissant à une diminution de l’expression de la NOS inductible et à une amélioration fonctionnelle et quantitative de la NOS endothéliale. L’administration chronique chez le rat de ciclosporine ou d’évérolimus induit une dysfonction endothéliale caractérisée par une altération de la voie de signalisation du NO et de l’EDHF et associée à une augmentation locale du stress oxydant. Au niveau musculaire cardiaque, seul l’évérolimus induit une augmentation de radicaux libres et une diminution de la respiration mitochondriale ventriculaire droite. L’administration préventive de polyphénols a permis, une amélioration de la composante EDHF de la dysfonction endothéliale, ciclosporine-induite, via une diminution de la surexpression de la NADPH oxydase et du stress oxydant vasculaire. Ainsi, le stress oxydant est une entité commune, impliquée dans la genèse de dysfonctions vasculaire et musculaire. Sa modulation par l’administration d’albumine ou de polyphénols a permis respectivement l’amélioration de l’hyporéactivité vasculaire du choc endotoxinique et de la dysfonction endothéliale dans nos deux modèles. / The aim of this work was to study the arterial and muscular dysfunctions in two rodent models of acute and chronic injuries, then the evaluation of pharmacological evaluation of oxidative stress on vascular abnormalities induced in these models.In the acute model, a mouse endotoxic shock, human serum albumin administration improved survival, endothelial dysfunction and reduced vascular hyporeactivity thanks to its concentration-dependant , anti-oxidative and anti-inflammatory properties, leading to a decrease of inductible NOS expression and an qualitative and quantitative increase of endothelial NOS.In the chronic model, rat’s administration of ciclopsorine and everolimus induced an endothelial dysfunction characterized by alterations of both NO and EDHF pathways and associated with an in situ oxidative stress. In the cardiac muscle, an increase of reactive oxygen species and a decrease of right ventricle mitochondrial respiratory chain complexes activities was observed only with everolimus. The preventive administration of polyphenols markedly increased the blunted EDHF component, but not the NO component, of the cyclosporine-induced endothelial dysfunction by reducing NADPH oxidase over expression and oxidative vascular stress. Finally, oxidative stress is a common entity, implicated in genesis of vascular and muscular dysfunctions. Its modulation by human albumin or polyphenols administration improves respectively arterial hyporeactivity of endotoxinic shock and endothelial dysfunction in our two models.
13

Les rhabdomyomes cardiaques dans la sclérose tubereuse de Bourneville : perturbations fonctionnelles cardiaques et perspectives thérapeutiques

Aw, Fatou 11 1900 (has links)
Novartis a subventionné ce projet de recherche / La sclérose tubéreuse de Bourneville (STB) est une affection caractérisée par la formation de tumeurs bénignes dans différents organes dont le cœur. Elle est due à la désinhibition de la cible mammalienne de la rapamycine (mTOR). Ces tumeurs encore appelées rhabdomyomes (RHM) au niveau cardiaque régressent spontanément dans la plupart des cas mais peuvent se compliquer d’arythmie ou d’obstruction ce qui peut compromettre le débit cardiaque et nécessiter un traitement. Les objectifs généraux de ce travail étaient d’étudier les perturbations des paramètres fonctionnels cardiaques et d’analyser la variabilité de la fréquece cardiaque chez une population porteuse de rhabdomyomes cardiaques dans la sclérose tubéreuse de Bourneville. Méthodes : Nous avons mené cette étude transversale entre février 2013 et mars 2015 afin de déterminer l'impact de la RHM sur le système de conduction cardiaque, sur l'homéostasie nerveuse autonome et sur le fonctionnement du coeur. Trente sujets avec TSC ont été recrutés pour participer à cette étude et ils ont été comparés à 13 contrôles sains qui étaient des membres de la famille libres de RHM. Les séries d’échocardiogrammes qui ont été précédemment enregistrées ont servi à documenter la taille de la tumeur au cours de la petite enfance. Un enregistrement Holter de 24 heures a été effectué pour la détection éventuelle d'arythmies et l'analyse de la variabilité de la fréquence cardiaque (VFC). Nous avons aussi rapporté quatre cas de régression de gros rhabdomyomes obstructifs chez des nouveaux nés sous everolimus par rapport à dix contrôles historiques non traités de notre centre. Résultats : La durée moyenne du suivi était de 4.5 ans. La prévalence des RHM était de 46.8% (37 RHM) entre 0-5 ans, 13.9% (11 RHM) entre 6-11 ans et 39.2% (31 RHM) entre 12- 33 ans. Dans 20% des cas, les RHM étaient responsables d’obstacles à l’éjection ou au remplissage du cœur. Les troubles du rythme retrouvés étaient de bénignes extrasystoles ventriculaires (55%) et des extrasystoles supraventriculaires (50%), Ces extrasystoles étaient plus fréquentes chez ces patients comparés à la population générale. Des arythmies significatives étaient notées chez 3 patients (30%) porteurs de large RHM: l’un présentait une tachycardie supraventriculaire sur syndrome de Wolff Parkinson White, l’autre une fibrillation auriculaire et le dernier des tachycardies supraventriculaires paroxystiques. Dans ii cette étude, nous avons aussi noté une augmentation de la variabilité de la fréquence cardiaque chez les cas dans les domaines et temporels spatial. En analyse régression linéaire on note une inversion de la pente de la courbe de variabilité de la fréquence cardiaque selon l'âge comparée à celle des témoins sains. Chez quatre patients pour qui les RHM obstructifs étaient traités par everolimus, la régression était en moyenne 11.8 fois plus rapide (droite de régression linéaire -0.0285 vs. -0.0024; p<0.001). La durée moyenne de régression de 50% de la taille des masses était de 1.13 ± 0.33 mois (extrêmes 0.66 à 1.4 mois) pour les patients traités par everolimus comparée à 72.9 ± 53.03 mois dans le groupe contrôle historique (p = 0.026). Aucun effet secondaire significatif n’a été observé. Conclusion: Dans cette série les arythmies cardiaques sont plus fréquentes chez les porteurs de sclérose tubéreuse de Bourneville comparés à la population générale avec une tendance plus importante chez les cas avec de gros rhabdomyomes. Pour ces derniers, l’everolimus est efficace pour la réduction de leur taille durant la période néonatale. Mais avec le peu de données de sécurité et d’innocuité disponibles cette approche thérapeutique ne doit être considérée que pour un nombre de cas limités. / Background: Tuberous Sclerosis Complex is caracterised by the formation of benign tumors in various organs, including the heart. It is caused by the disinhibition of the mammalian target of rapamycin (mTOR) protein. RHM (rhabdomyomas) regress spontaneously in most cases but can be complicated by serious arrhythmias or obstruction that may compromise cardiac output requiring treatement. The main objectives of this work were to study functional and electrical cardiac desorders and to analyze the heart rate variability in population of TSC with cardiac rhabdomyoma. Methods: We conducted this cross-sectional study between February 2013 and March 2015 to determine the impact of HMR on the cardiac conduction system and on autonomic nervous homeostasis. Thirty subjects with TSC were recruited to participate in this study and compared to 13 healthy controls that were free family members of RHM. The serial echocardiograms that were previously recorded were used to document the size of the tumor during early childhood. A 24-hour Holter record was performed for possible arrhythmia detection and heart rate variability (VFC) analysis. Results: The median follow-up time was 4.5 years. The prevalence of RHM was 46.8% (37 RHM) between 0-5 years, 39.2% (31 RHM) between 12-33 years and 13.9% (11 RHM) between 6-11 years. RHM causes in 20% an obstacle to inflow or outflow tract. The encountered benign arrhythmias founded were isolated ventricular premature beats (55%) and supraventricular premature beats (50%), which were 2 times fold and 4 times fold more compared to reported prevalence in the general pediatric population, respectively (p<0.05). Significant arrhythmias were noted in 3 (30%) patients with large RHM: one patient with Wolff Parkinson White syndrome had supraventricular tachycardia, one with atrial fibrillation, a third patient had symptomatic paroxysmal supraventricular tachycardia. There was a trend which did not reach statistical significance difference in the prevalence of cardiac arrhythmias between cases with small versus large RHM (p=0.07). In this study heart rate variability was increased in patients with TSC according to time, frequency and non-linear domains. For this heart rate variabity TSC patients with RHM showed an inversed relationship towards age compared to controls, Studies from four everolimus treated cases were compared to 10 controls. Compared to historic controls, everolimus treated patients had a RHM size regression rate 11.8 times faster (linear regression slope -0.0285 vs. -0.0024; p<0.001). The average time to 50% size reduction was 1.13 ± 0.33 month (range 0.66 to 1.4 months) for everolimus treated patients compared to 72.9 ± 53.03 months in the historic controls (p = 0.026). No significant side effect were observed. Conclusion: In this series, arrhythmia was more prevalent in TSC compared to general pediatric population, with a trend towards higher prevalence in cases with larger RHM. Everolimus is effective for size reduction of RHM during the neonatal period. With limited safety data this approach should be used with caution, only in selective cases.
14

Etudes des voies somatostatinergiques et Pi3Kinase-Akt-mTOR dans les tumeurs intra-crâniennes (Adénomes hypophysaires, Méningiomes, Chordomes) / Pi3Kinase-Akt-mTOR and somatostatin pathways study in intra-cranial tumors (pituitary adenomas, meningiomas, and chordomas)

Graillon, Thomas 01 December 2014 (has links)
1. Adénomes hypophysaires somatotropes : Elaboration d'un modèle in vitro et in vivo d'études du récepteur SST2 et des voies de signalisation somatostatinergiques.Afin de préciser l'étude du récepteur SST2, nous avons mis en place un modèle d'étude in vitro et in vivo, en établissant une lignée polyclonale exprimant le récepteur SST2 humain à de hauts niveaux. Ce modèle nous permettra de tester de nouveaux agonistes somatostatinergiques comme le pasiréotide et d'étudier de façon approfondie les voies de signalisation.2. Méningiomes : Mise en place d'un modèle de culture primaire de méningiome in vitro et étude de l'effet de l'octréotide, du pasiréotide et de l'everolimus sur la prolifération cellulaire et les voies de signalisation intracellulaire.Etant donné la forte expression du récepteur SST2, nous avons démontré in vitro un effet anti-prolifératif de l'octréotide sur les cellules de méningiomes via une inhibition de la voie Pi3kinase-Akt-mTOR. L'octréotide a significativement amélioré l'inhibition par l'everolimus de la prolifération cellulaire.Un effet additif des 2 drogues a été observé. Ces résultats ont permis la mise en place d'une étude clinique . Par ailleurs, on observe un meilleur effet du pasiréotide comparé à celui de l'octréotide.3. Chordomes : Mise au point d'un modèle de culture primaire de cellules de chordomes in vitro et études préliminaires.Les premiers résultats avec octréotide, pasiréotide et everolimus sont concluants, mettant en évidence une diminution de la prolifération cellulaire, et nous incitent à poursuivre les investigations. / 1.Somatotroph adenomas : Development of an in vitro and in vivo model to study SST2 receptor and somatostatin pathway.To precise SST2 role in tumorigenesis, we developed an in vitro and in vivo model, using a polyclonal cell line with high and stable SST2 expression level. This model will provide to test new somatostatin agonists as pasireotide and further studies on intracellular pathway in ''somatotroph'' context.2. Meningiomas : Development of a model of meningioma primary culture in vitro with study of octreotide, pasireoide and everolimus effects on cell proliferation and intracellular pathways. Given the strong SST2 expression, we demonstrated an in vitro antiproliferative effect of octreotide on meningioma cells via an inhibition of Pi3kinase-Akt-mTOR pathway.In vitro, we observed that octreotide significantly improved everolimus induced cell proliferation inhibition. An additive effect of the 2 drugs was observed in each tested tumor. These results supported the development of a clinical trial. Pasireotide provided a better effect than octreotide, alone or in combination with everolimus on cell proliferation and intracellular pathways.3. Chordomas : Development of an in vitro model of chordoma cell primary culture with preliminary studies.We developed a model of in vitro chordoma cell culture. This model is reliable and stable, providing study of different drugs. SST2 receptor expression was lower than in meningiomas but SST2 expression remained significant in the majority of the tumors. First results with octreotide, pasireotide and everolimus are relevant, with a decrease in cell proliferation leading to further studies.
15

Einfluss von unterschiedlichen immunsuppressiven Strategien auf Proliferation, Stoffwechsel und Differenzierung humaner fetaler neuraler Progenitorzellen in vitro: Einfluss von unterschiedlichen immunsuppressiven Strategien aufProliferation, Stoffwechsel und Differenzierung humaner fetalerneuraler Progenitorzellen in vitro

Glien, Anja 15 January 2015 (has links)
The influence of immunosuppressive drugs on neural stem/progenitor cell fate in vitro.
16

A participação da via fosfatidilinositol3-quinase (PI3K)/mTOR no carcinoma epidermoide oral / The participation of the pathway Phosphatidylinositol 3-kinase (PI3K) / mTOR in oral squamous cell carcinoma

Andressa Duarte 15 March 2018 (has links)
O carcinoma epidermoide oral (CEO) possui alta incidência no Brasil, correspondendo a aproximadamente 95% das neoplasias malignas orais. A biologia molecular do carcinoma de cabeça e pescoço é complexa e se desenvolve a partir da disfunção de várias vias inter-relacionadas. A via das PI3K/mTOR é conhecida por regular várias funções celulares, como a regulação do ciclo celular, migração, angiogênese, morfologia e organização do citoesqueleto. O presente trabalho teve como objetivo avaliar o impacto do bloqueio da via PI3K e mTOR na sobrevida celular, na adesão e na morfologia de células endoteliais, relacionando-o com o processo angiogênico. Em cultura de células, observamos que as inibições farmacológicas de PI3K ou do mTOR diminuem a viabilidade celular do CEO. Houve redução da expressão de PARP, um marcador de apoptose e pS6, uma proteína dowstream na sinalização do mTOR, após o tratamento das células de CEO com os inibidores de mTOR. Além disso, demonstramos que o tratamento com os inibidores de mTOR diminuem a capacidade das células do CEO em formarem clones. Foi observado ainda que o cultivo de célula endoteliais da veia umbilical humana (HUVEC, do inglês Human Umbilical Vein Endothelial Cells) em meio condicionado (MC) proveniente de células de CEO, tratadas com inibidores de mTOR, resultaram em aumento da adesão celular e modificação na morfologia celular. Para investigar a influência dos fatores liberados pelas células tumorais na migração das células HUVECs, foi realizado ensaio de wound healing, em células HUVECs cultivadas em MC. Observamos maior migração das células HUVECs cultivadas em MC quando este era proveniente de células cancerosas tratadas com inibidor de mTOR. Ainda, investigamos a expressão da via VEGF nessa migração por meio do ensaio de ELISA. Observamos que no MC proveniente de células cancerosas tratadas com inibidor de mTOR havia maior presença de VEGF. Nossos dados sugerem que a via da PI3K/mTOR está envolvida na proliferação das células do CEO. Porém, a inibição de mTOR em células cancerosas pode liberar fatores, tais como VEGF, que influenciam na morfologia e migração de células HUVEC. / Oral squamous cell carcinoma (OSCC) has a high incidence in Brazil, corresponding to approximately 95% of oral malignancies. The molecular biology of head and neck carcinoma is complex and develops from the dysfunction of several interrelated pathways. The PI3K/mTOR pathway is known to regulate various cellular functions, such as cell cycle regulation, migration, angiogenesis, cytology, and cytoskeletal organization. The aim of the present study was to evaluate the impact of PI3K and mTOR pathway blockade on cell survival, endothelial cell adhesion and morphology, and to correlate it with the angiogenic process. In cell culture, we observed that pharmacological inhibitions of PI3K or mTOR decrease the OSCC\'s cellular viability. There was a reduction in the expression of PARP, a marker of apoptosis and pS6, a dowstream protein in mTOR signaling, after treatment of OSCC cells with mTOR inhibitors. In addition, we have demonstrated that treatment with mTOR inhibitors decreases the ability of the OSCC cells to form clones. It was further noted that human umbilical vein endothelial cell (HUVEC) culture in conditioned media (CM) from OSCC cells treated with mTOR inhibitors resulted in increased cell adhesion and modification in cell morphology. To investigate the influence of the factors released by the tumor cells in the migration of HUVEC cells, a wound healing assay was performed on HUVEC cells cultured in CM. We observed a greater migration of HUVECs cells cultured in CM when it came from cancer cells treated with mTOR inhibitor. Furthermore, we investigated the role of the VEGF pathway in this migration through the ELISA assay. We observed that in CM from cancer cells treated with mTOR inhibitor there was a greater presence of VEGF. Our data suggest that the PI3K/mTOR pathway is involved in the proliferation of OSCC cells. However, inhibition of mTOR in cancer cells may release factors, such as VEGF, which influence the morphology and migration of HUVEC cells.
17

A participação da via fosfatidilinositol3-quinase (PI3K)/mTOR no carcinoma epidermoide oral / The participation of the pathway Phosphatidylinositol 3-kinase (PI3K) / mTOR in oral squamous cell carcinoma

Duarte, Andressa 15 March 2018 (has links)
O carcinoma epidermoide oral (CEO) possui alta incidência no Brasil, correspondendo a aproximadamente 95% das neoplasias malignas orais. A biologia molecular do carcinoma de cabeça e pescoço é complexa e se desenvolve a partir da disfunção de várias vias inter-relacionadas. A via das PI3K/mTOR é conhecida por regular várias funções celulares, como a regulação do ciclo celular, migração, angiogênese, morfologia e organização do citoesqueleto. O presente trabalho teve como objetivo avaliar o impacto do bloqueio da via PI3K e mTOR na sobrevida celular, na adesão e na morfologia de células endoteliais, relacionando-o com o processo angiogênico. Em cultura de células, observamos que as inibições farmacológicas de PI3K ou do mTOR diminuem a viabilidade celular do CEO. Houve redução da expressão de PARP, um marcador de apoptose e pS6, uma proteína dowstream na sinalização do mTOR, após o tratamento das células de CEO com os inibidores de mTOR. Além disso, demonstramos que o tratamento com os inibidores de mTOR diminuem a capacidade das células do CEO em formarem clones. Foi observado ainda que o cultivo de célula endoteliais da veia umbilical humana (HUVEC, do inglês Human Umbilical Vein Endothelial Cells) em meio condicionado (MC) proveniente de células de CEO, tratadas com inibidores de mTOR, resultaram em aumento da adesão celular e modificação na morfologia celular. Para investigar a influência dos fatores liberados pelas células tumorais na migração das células HUVECs, foi realizado ensaio de wound healing, em células HUVECs cultivadas em MC. Observamos maior migração das células HUVECs cultivadas em MC quando este era proveniente de células cancerosas tratadas com inibidor de mTOR. Ainda, investigamos a expressão da via VEGF nessa migração por meio do ensaio de ELISA. Observamos que no MC proveniente de células cancerosas tratadas com inibidor de mTOR havia maior presença de VEGF. Nossos dados sugerem que a via da PI3K/mTOR está envolvida na proliferação das células do CEO. Porém, a inibição de mTOR em células cancerosas pode liberar fatores, tais como VEGF, que influenciam na morfologia e migração de células HUVEC. / Oral squamous cell carcinoma (OSCC) has a high incidence in Brazil, corresponding to approximately 95% of oral malignancies. The molecular biology of head and neck carcinoma is complex and develops from the dysfunction of several interrelated pathways. The PI3K/mTOR pathway is known to regulate various cellular functions, such as cell cycle regulation, migration, angiogenesis, cytology, and cytoskeletal organization. The aim of the present study was to evaluate the impact of PI3K and mTOR pathway blockade on cell survival, endothelial cell adhesion and morphology, and to correlate it with the angiogenic process. In cell culture, we observed that pharmacological inhibitions of PI3K or mTOR decrease the OSCC\'s cellular viability. There was a reduction in the expression of PARP, a marker of apoptosis and pS6, a dowstream protein in mTOR signaling, after treatment of OSCC cells with mTOR inhibitors. In addition, we have demonstrated that treatment with mTOR inhibitors decreases the ability of the OSCC cells to form clones. It was further noted that human umbilical vein endothelial cell (HUVEC) culture in conditioned media (CM) from OSCC cells treated with mTOR inhibitors resulted in increased cell adhesion and modification in cell morphology. To investigate the influence of the factors released by the tumor cells in the migration of HUVEC cells, a wound healing assay was performed on HUVEC cells cultured in CM. We observed a greater migration of HUVECs cells cultured in CM when it came from cancer cells treated with mTOR inhibitor. Furthermore, we investigated the role of the VEGF pathway in this migration through the ELISA assay. We observed that in CM from cancer cells treated with mTOR inhibitor there was a greater presence of VEGF. Our data suggest that the PI3K/mTOR pathway is involved in the proliferation of OSCC cells. However, inhibition of mTOR in cancer cells may release factors, such as VEGF, which influence the morphology and migration of HUVEC cells.
18

Accidental Overdose of Everolimus Secondary to Poor Patient Education

LaBrosse, A. D., Bossaer, John B. 01 December 2013 (has links)
No description available.
19

Intervention biologique dans les cancers hormono-dépendants. / Biological intervention on hormone dependant cancers

Pouget, Mélanie 08 July 2016 (has links)
Les cancers hormono-dépendants : le cancer du sein et de la prostate, sont les plusfréquents respectivement chez la femme et chez l’homme. Ces cancers représentent unproblème majeur de santé publique. Malgré les améliorations du dépistage et des traitementscuratifs, ces cancers peuvent devenirs métastatiques et le traitement devient alors palliatif. Ace stade, les thérapeutiques sont déjà très avancées avec une prise en charge qui repousse deplus en plus la fin de vie du patient tout en conservant au mieux sa qualité de vie. Au stademétastatique, différentes stratégies peuvent être envisagées pour tenter de rallonger la surviedes patients : une médecine personnalisée en ciblant des voies de signalisation particulière ;une autre voie d’approche peut être une intervention nutritionnelle. En effet, les bienfaits decertains composants nutritionnels « anti-cancer » sont de plus en plus connus et étudiés.L’objectif de ce travail a été d’étudier ces deux approches dans la prise en chargethérapeutique de ces 2 cancers hormono dépendants en prenant le cas de l’évérolimus commethérapie ciblée et le cas de la curcumine comme composé nutritionnel.Une base de données rétrospective a été réalisée chez des patientes atteintes d’uncancer du sein métastatique (n = 63) et recevant de l’évérolimus en combinaison avecl’hormonothérapie (EHT). L’objectif de ce travail était d’étudier la réponse à cette nouvellecombinaison associant une thérapie ciblée et une hormonothérapie et de comparer cesdonnées à une ancienne base de données (PMID 21852136) qui cherchait à savoir l’intérêt detraiter les patientes avec plusieurs lignes de chimiothérapie. Il a été montré une améliorationde la survie chez les patientes traitées par EHT comparativement à une chimiothérapie et cettedifférence est significative lorsque les patientes sont traitées avec moins de 2 lignes dechimiothérapies antérieures.La seconde approche était d’évaluer la combinaison de l’association Taxotère® pluscurcumine dans le cancer de la prostate résistant à la castration et dans le cancer du seinmétastatique.Un essai pilote de phase II a évalué l’association Taxotère® plus curcumine enpremière ligne de traitement des cancers de la prostate métastatiques hormono-résistants sur30 patients. Cette association a permis d’obtenir un taux de réponse du PSA de 59% et untaux de réponse objective de 40% pour les patients présentant des cibles mesurables. Letraitement a été très bien toléré avec une dose de curcumine de 6 grammes par jour pendant 7jours.Deux études de phase II randomisés sont en cours :- CURRYTAX, un essai multicentrique randomisé de phase II comparant le Taxotère® enmonothérapie à l’association Taxotère® plus curcumine en première ou deuxième ligne detraitement des cancers du sein inopérables, en rechute ou métastatiques, Her2 négatifs.- CURTAXEL, un essai multicentrique randomisé de phase II en double aveuglecomparant l’association Taxotère® plus curcumine versus Taxotère® plus placebo enpremière ligne de traitement des cancers de la prostate métastatiques résistants à la castration.Des résultats préliminaires vont être présentés dans ce manuscrit, avant l’analyseintermédiaire prévue après l’inclusion et le suivi des 50 premiers patients. L’étude de lapopulation, de la compliance, de la réponse objective, de la survie, du temps jusqu’àprogression, de la réponse du PSA, du suivi des marqueurs (CEA, CA15-3) vont êtreprésentés dans ce manuscrit sur 30 patientes dans l’étude CURRYTAX et sur 33 patients dansl’étude CURTAXEL.Ces travaux montrent l’intérêt de telles approches et ouvrent des pistes à exploiter en cequi concerne une intervention biologique dans le cancer du sein et celui de la prostate que cesoit par une intervention nutritionnelle telle que la curcumine ou bien via un mécanisme surune voie de signalisation. / Hormone dependent cancers like breast cancer and prostate cancers are the two mostcommon cancers in woman and man and is a major health concern. Despite the improvementof early detection methods and curative treatments, cancers become metastatic and treatmentbecome palliative. At metastatic stage, different treatments can be tested to control the growthlonger and relieve symptoms caused by it to help prolong life and preserve quality of life.Metastatic cancer may be treated with targeted therapy depending on specific characteristic,nutrition therapy can also help as the benefit of nutritional science against cancer knowledgehas increased and more research are being done on this method to show its effectiveness.The purpose of this work was to compare 2 different therapies using the Everolimus plusHormonotherapy (EHT) treatment as targeted therapy and Taxotere plus Curcumin asnutrition therapy.A retrospective database was realised on 63 metastatic breast cancer patients who receivedEverolimus plus Hormonotherapy (EHT) as targeted therapy. This aim of this database was toevaluate the efficacy of this combined treatment and compare data with an existing database(PMID21852136) which looked at the benefits of treating patients with numerous lines ofchemotherapy.The survival was improved for patients who received EHT compared to patients whoreceived chemotherapy. The study shows that EHT resulted in a longer overall survival ratefor patient pre-treated with less than 2 CT lines.In the second part of this work, we analysed the efficacy of a combination Taxotere pluscurcumin in castration resistant prostate cancer and metastatic breast cancer patients.A phase II study evaluated the combination of Taxotere® and curcumin in first linetreatment of metastatic castration resistant prostate cancer on 30 patients. The PSA responserate was 59% and the objective tumor response rate was 40% for patient with measurabletargets. This treatment was well tolerated with a daily dose of 6g for 7days.Two phase II randomized studies are currently recruiting:-CURRYTAX, a randomized multicenter phase II trial assessing Taxotere as amonotherapy versus Taxotere plus curcumin in first and second lines cancer treatments forinoperable, recurring or metastatic HER2- Negative breast cancer patients.-CURTAXEL, a randomized double blind multicenter phase II trial comparing Taxotereplus curcumin versus Taxotere plus placebo in first line cancer treatment for metastaticcastration resistant prostate cancer patients.Preliminary results will be included in this manuscript before the planned intermediateanalysis, after enrollment of 50 patients. Population, compliance, objective response, overallsurvival, time to progression, PSA response, markers assessment (CEA, CA15-3) will also bepresented in this manuscript on 30 and 33 patients in CURRYTAX and CURTAXEL trials,respectively.These clinical results show the interest of such approaches and permit to explore furtherbiological pathway in breast and prostate cancer, either through nutritional therapy usingcurcumin or through a signalling pathway.
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Optimisation des thérapeutiques immunosuppressives par méthode pharmacologique. / Optimization of immunosuppressive therapy using pharmacological method

Lemaitre, Florian 30 September 2014 (has links)
Les immunosuppresseurs sont des médicaments ayant démontré leur efficacité dans la prévention du rejet de transplantation d’organe solide. Néanmoins, ces médicaments présentent une importante variabilité de la réponse pharmacologique notamment liée à une variation de leur pharmacocinétique. Cette variabilité peut être à l’origine d’un défaut d’efficacité du traitement ou de sur-expositions entrainant une toxicité. Le suivi thérapeutique pharmacologique (STP) des concentrations sanguines d’immunosuppresseur permet de limiter ces risques de sur ou de sous-exposition en facilitant l’adaptation de posologie de ces traitements. En dépit de l'utilisation intensive du STP des concentrations d'immunosuppresseurs chez le transplanté d'organe, la fréquence du rejet aigu a peu diminué au cours de ces dernières années et reste élevée. Le rejet aigu cellulaire peut, en outre, survenir chez le patient alors même que ses concentrations sanguines sont en zone thérapeutique. C'est pourquoi la recherche d'améliorations de ce suivi thérapeutique ainsi que la recherche de nouveaux moyens de monitoring sont des axes pertinents d'investigation en pharmacologie des immunosuppresseurs. L’objectif de ce travail de doctorat a été de développer de nouveaux outils pharmacologiques de monitoring de l’effet de deux immunosuppresseurs, l’évérolimus et le tacrolimus, dans le but de participer à la maitrise de la variabilité pharmacologique de l’effet immunosuppresseur. Pour la première fois, la pharmacocinétique de l'évérolimus chez le transplanté cardiaque a été modélisée par une approche de population. La modélisation pharmacologique est un des axes actuels d’amélioration du STP des immunosuppresseurs permettant d’évaluer l’impact de covariables démographiques, biologiques et/ou génétiques sur la pharmacocinétique de ces médicaments. L’élaboration de ce modèle doit permettre une individualisation des posologies conduisant à la limitation de la variabilité pharmacocinétique lors d’un traitement par cette molécule.Au cours de ce travail, deux méthodes analytiques ont également été développées par LC-MS/MS pour le dosage intracellulaire de l’évérolimus et du tacrolimus. La mesure des concentrations des immunosuppresseurs à l’intérieur même de la cellule, c’est à dire au niveau de son site d’action, apparait comme une mesure plus pertinente que la simple mesure des concentrations dans le sang. Ces méthodes ont ensuite été évaluées sur des petites cohortes de patients transplantés cardiaques. La faisabilité de tels dosages a été démontrée et a permis la réalisation de la dernière partie présentée au cours de ce travail. En effet, une étude clinique a été réalisée chez le patient transplanté hépatique de novo en vue de rapprocher les concentrations sanguines et intracellulaires de tacrolimus et l'effet sur la protéine cible, la calcineurine. Pour la première fois des pharmacocinétiques intracellulaires complètes ont pu être obtenues permettant la description de la cinétique intracellulaire du tacrolimus. Cette étude a également permis de mettre en évidence et de décrire la relation dose - concentration sanguine - concentration intracellulaire - effet sur la protéine cible du tacrolimus chez le transplanté hépatique. Ces travaux ont permis de jeter les bases nécessaires à la réalisation d'essais cliniques permettant d'évaluer la pertinence d'un suivi longitudinal des concentrations intracellulaires et/ou de l'activité de la calcineurine dans la prévention de rejet de transplantation. Les outils développés au cours de ce travail de doctorat visent, d’une part, à mieux appréhender la variabilité de la réponse pharmacologique au cours d’un traitement immunosuppresseur et, d’autre part, à être des outils de compréhension des mécanismes pharmacocinétiques et cellulaires de ces traitements. L'utilisation de ces outils doit concourir à la diminution de la fréquence du rejet de greffe et à l'amélioration globale de la prise en charge du patient transplanté d'organe. / Immunosuppressive drugs have proven efficacy in the prevention of acute rejection of solid organ transplantation. However, these drugs exhibit substantial variability in pharmacological response due to such a variation in their pharmacokinetics. This variability may be the cause of underexposure with a lack of efficacy or over-exposure causing toxicity. Therapeutic drug monitoring (TDM) of immunosuppressant blood levels can limit the risk of over or underexposure facilitating dosage adjustment of these treatments. Despite the extensive use of TDM, the incidence of acute rejection has declined somewhat in recent years and remains high (in the order of 8-15%). Acute cellular rejection can further occur in patients even though blood levels are within the therapeutic range. That is why improvements in the therapeutic monitoring and new ways of monitoring are relevant lines of investigation in pharmacology.The objective of this phD work was to develop new pharmacological tools for monitoring the effect of two immunosuppressive drugs, everolimus and tacrolimus in order to control the pharmacological variability of the immunosuppressive effect .For the first time, the pharmacokinetics of everolimus in heart transplant was modeled by a population approach. Pharmacological modeling is one of the current areas of improvement of immunosuppressants TDM which allows evaluating the impact of demographic, biological and / or genetic on the pharmacokinetics of these drugs covariates. The development of this model must allow individualization of dosages leading to limit pharmacokinetic variability during treatment with this drug.During this work, two analytical methods were also developed by LC-MS/MS for assaying intracellular tacrolimus and everolimus concentrations. Measuring intracellular concentrations of immunosuppressive drugs, i.e. at its site of action, appears as a more relevant than measuring blood concentrations. These methods were then evaluated on small cohorts of heart transplant patients. The feasibility of such assays has been demonstrated and led to the completion of the last part presented in this work.Indeed, a clinical study was performed in de novo liver transplant patients to evaluate blood and intracellular concentrations of tacrolimus and their effect on the target protein, calcineurin. For the first time complete intracellular pharmacokinetics have been obtained for the description of the profile of the intracellular kinetics of tacrolimus. This study also highlights and describes the relationship dose - blood concentration - intracellular concentration - effect on the target protein of tacrolimus in liver transplant patients. This work might help conducting clinical trials to assess the relevance of a longitudinal follow-up of intracellular concentrations and / or activity of calcineurin in the prevention of transplant rejection.The tools developed in this PhD work aimed, firstly, to better understand the variability of the pharmacological response in immunosuppressive therapy and, secondly, to be tools for understanding the drug mechanisms inside of the cell. The use of these tools should contribute to the decrease in the frequency of graft rejection and the overall improvement in the management of organ transplant patients.

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