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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.
1

Pesquisa pré-clínica e clínica de um gel termorreversível contendo extrato padronizado de própolis (EPP-AF) para a redução do tempo de cicatrização de lesões em pacientes queimados / Pre-clinical and clinical research of a thermoreversible gel formulation containing standardized propolis extract (EPP-AF) to reduce healing time of lesions in burn victims.

Berretta, Andresa Aparecida 12 November 2007 (has links)
O estudo realizado compreendeu a avaliação pré-clínica e clínica de uma forma farmacêutica de liberação sustentada contendo extrato padronizado de própolis EPP-AF para o tratamento de queimaduras. Utilizamos um polímero com características termorreversíveis que possibilitaram a obtenção de um produto que se mantém na forma líquida quando a baixas temperaturas e geleifica in situ. A forma farmacêutica proposta visa maior comodidade e adesão do paciente, obtenção de um tecido epitelial organizado e menor tempo para a cicatrização da área. Neste trabalho, foi avaliada a atividade antimicrobiana in vitro, do extrato de própolis e dos géis obtidos, através da técnica de difusão em agar e também através do método de microdiluição em microplacas contendo caldo de enriquecimento e o revelador trifeniltetrazólio, frente aos microrganismos S. aureus, M. luteus e P. aeruginosa. O potencial mutagênico foi estudado em modelo experimental utilizando micronúcleos de sangue periférico de ratos wistar. A histologia do tecido formado em lesão induzida com a utilização de um punch para biópsia e a eficácia do produto em pacientes queimados também foram objeto deste estudo. As áreas doadoras foram utilizadas como modelos experimentais. Os resultados demonstraram que o extrato de própolis apresentou atividade frente aos microrganismos pesquisados sendo que os géis não se difundiram em disco. Em microdiluição, o modelo utilizado para estudo da atividade antimicrobiana não foi adequado ao microrganismo M. luteus, mas foi possível a obtenção do CIM para S. aureus e P. aeruginosa, que foram respectivamente, 50 ug/mL e 200 ug/mL. O produto não apresentou potencial genotóxico nos tratamentos agudo, sub-agudo e crônico. A pesquisa clínica demonstrou que o gel termorreversível contendo extrato padronizado de própolis 3,6%p/v apresentou tempo de cicatrização semelhante à pomada contendo nitrofurazona (furacin®), tratamento referência utilizado na Unidade de Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. / The present paper examines the pre-clinical and clinical evaluation of a pharmaceutical form that provides sustained delivery of a formulation containing standardized propolis extract EPP AF to the treatment of burn wounds. There has been used a polymer with thermoreversible characteristics which made possible the obtaintion of a product that maintains its liquid state in low temperatures and provides in situ gelling property. The proposed pharmaceutical form intends to enhance patients comfort and acceptance, to obtain a histological well-organized skin tissue and to reduce wound healing time. This study evaluated in vitro the antimicrobial activity of propolis extract and obtained gels using the agar-diffusion method and also a broth microdilution method with microdillution in microplates containing serially diluted antimicrobial and triphenilthetrazolium agent, against microorganisms S. aureus, M. luteus e P. aeruginosa, the mutagenic potential using micronuclei of peripheral blood Wistar rats experimental models, the histology of neo-formed tissue induced by lesions done with a punch and the effectiveness of the products in burn patients, using skin-grafting donnor sites like experimental models. The results show that propolis extract has activity against the listed microorganisms and that the gels did not spread into agar medium plate. In the microdilution method, the used model for the antimicrobial activity study is not adequate to the microorganism M. luteus, but it was possible for the obtention of CIM to S. aureus e P. aeruginosa, which were, respectively, 50 ug/mL e 200 ug/mL. The product did not show genotoxic potential to acute, subacute and chronic treatments. The clinical research show that the thermoreversible gel formulation containing standardized propolis extract 3,6%p/v presented wound healing time similar to the reference treatment used in the Burn Victims Unity witch is nitrofurazone cream (furacin®).
2

Pesquisa pré-clínica e clínica de um gel termorreversível contendo extrato padronizado de própolis (EPP-AF) para a redução do tempo de cicatrização de lesões em pacientes queimados / Pre-clinical and clinical research of a thermoreversible gel formulation containing standardized propolis extract (EPP-AF) to reduce healing time of lesions in burn victims.

Andresa Aparecida Berretta 12 November 2007 (has links)
O estudo realizado compreendeu a avaliação pré-clínica e clínica de uma forma farmacêutica de liberação sustentada contendo extrato padronizado de própolis EPP-AF para o tratamento de queimaduras. Utilizamos um polímero com características termorreversíveis que possibilitaram a obtenção de um produto que se mantém na forma líquida quando a baixas temperaturas e geleifica in situ. A forma farmacêutica proposta visa maior comodidade e adesão do paciente, obtenção de um tecido epitelial organizado e menor tempo para a cicatrização da área. Neste trabalho, foi avaliada a atividade antimicrobiana in vitro, do extrato de própolis e dos géis obtidos, através da técnica de difusão em agar e também através do método de microdiluição em microplacas contendo caldo de enriquecimento e o revelador trifeniltetrazólio, frente aos microrganismos S. aureus, M. luteus e P. aeruginosa. O potencial mutagênico foi estudado em modelo experimental utilizando micronúcleos de sangue periférico de ratos wistar. A histologia do tecido formado em lesão induzida com a utilização de um punch para biópsia e a eficácia do produto em pacientes queimados também foram objeto deste estudo. As áreas doadoras foram utilizadas como modelos experimentais. Os resultados demonstraram que o extrato de própolis apresentou atividade frente aos microrganismos pesquisados sendo que os géis não se difundiram em disco. Em microdiluição, o modelo utilizado para estudo da atividade antimicrobiana não foi adequado ao microrganismo M. luteus, mas foi possível a obtenção do CIM para S. aureus e P. aeruginosa, que foram respectivamente, 50 ug/mL e 200 ug/mL. O produto não apresentou potencial genotóxico nos tratamentos agudo, sub-agudo e crônico. A pesquisa clínica demonstrou que o gel termorreversível contendo extrato padronizado de própolis 3,6%p/v apresentou tempo de cicatrização semelhante à pomada contendo nitrofurazona (furacin®), tratamento referência utilizado na Unidade de Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. / The present paper examines the pre-clinical and clinical evaluation of a pharmaceutical form that provides sustained delivery of a formulation containing standardized propolis extract EPP AF to the treatment of burn wounds. There has been used a polymer with thermoreversible characteristics which made possible the obtaintion of a product that maintains its liquid state in low temperatures and provides in situ gelling property. The proposed pharmaceutical form intends to enhance patients comfort and acceptance, to obtain a histological well-organized skin tissue and to reduce wound healing time. This study evaluated in vitro the antimicrobial activity of propolis extract and obtained gels using the agar-diffusion method and also a broth microdilution method with microdillution in microplates containing serially diluted antimicrobial and triphenilthetrazolium agent, against microorganisms S. aureus, M. luteus e P. aeruginosa, the mutagenic potential using micronuclei of peripheral blood Wistar rats experimental models, the histology of neo-formed tissue induced by lesions done with a punch and the effectiveness of the products in burn patients, using skin-grafting donnor sites like experimental models. The results show that propolis extract has activity against the listed microorganisms and that the gels did not spread into agar medium plate. In the microdilution method, the used model for the antimicrobial activity study is not adequate to the microorganism M. luteus, but it was possible for the obtention of CIM to S. aureus e P. aeruginosa, which were, respectively, 50 ug/mL e 200 ug/mL. The product did not show genotoxic potential to acute, subacute and chronic treatments. The clinical research show that the thermoreversible gel formulation containing standardized propolis extract 3,6%p/v presented wound healing time similar to the reference treatment used in the Burn Victims Unity witch is nitrofurazone cream (furacin®).
3

Spectométrie de RMN quantitative in vivo pour la mesure des lipides hépatiques chez l'homme et des métabolites cérébraux chez un modèle murin de neuro-inflammation / In vivo quantitative NMR Spectrocopy for the measurement of human liver fats and of cerebral metabolites in a neuroinflamation murine model

Bucur, Adriana 22 June 2010 (has links)
La SRM proton constitue un outil non invasif unique pour l'exploration biochimique quantitative des tissus vivants. Les deux études présentées dans cette thèse visent à maîtriser chacune des phases impliquées depuis l’acquisition des données jusqu’à l’estimation fiable et précise des profils métaboliques des tissus explorés. Des protocoles expérimentaux d’acquisition des signaux de spectrométrie de résonance magnétique proton in vivo à temps d’écho courts ont été définis puis optimisés pour une application pré-clinique (souris) sur un imageur 4.7T et pour une étude en environnement clinique menée à 1.5T. La première étude a permis de mesurer longitudinalement les altérations des métabolites cérébraux (N-acétyl-aspartate, choline, créatine, taurine) chez un modèle murin de neuro-inflammation sur un imageur 4.7T, et la seconde étude avait pour objectif la mesure de la quantité totale et la composition lipidique hépatique en environnement clinique à 1.5T chez des sujets stéatosiques. Des méthodes d’estimation des contributions métaboliques et lipidiques adaptées aux propriétés physiques de signaux ont été validées pour chacune de ces applications. Ces méthodes sont fondées sur des algorithmes de moindres carrés non linéaires. Des stratégies multi-tirages des valeurs initiales et des contraintes ont été favorablement validées. Les atouts et les originalités de ce projet reposent sur les développements synergiques des protocoles d’acquisitions et des méthodes de traitement du signal associées. Ces développements ont pour vocation d’enrichir la palette des informations biochimiques collectées pour l’aide au pronostic et diagnostic médical / The proton MRS is a unique non-invasive method to quantitative biochemical exploration of living tissues. The studies presented in this thesis aim to handle each one of the involved steps, from data acquisition to reliable and precise metabolic profile estimation of explored tissues. Protocols for experimental acquisition of in vivo, short echo-time magnetic resonance signals were defined, and optimized for a pre-clinical application (mice) on a 4.7T scanner and for a clinical study at 1.5T. The first study allowed yo measuring cerebral metabolite (N-acetyl-aspartate, choline, creatine, taurine) alterations along time in a murine model of neuro-inflammation on a 4.7T scanner and the second study aimed to measure the total quantity and the composition of liver fat in patients with hepatic steatosis in a clinical environment at 1.5T. Signal processing methods for metabolite and fat contribution estimates, coping with physical signal properties were validated for both studies. These methods are based on non-linear least squares algorithms. Multiple starting values and constraints strategies were successfully validated. The assets and the originality of this project are based on the synergic developments of acquisition protocols and the associated signal processing methods. These developments were designed to enrich the list of the biochemical information non-invasively measured, in order to help medical prognostic and diagnostic
4

Modélisation de l’ablation radiofréquence pour la planification de la résection de tumeurs abdominales / Computational modeling of radiofrequency ablation for the planning and guidance of abdominal tumor treatment

Audigier, Chloé 14 October 2015 (has links)
L'ablation par radiofréquence (ARF) de tumeurs abdominales est rendue difficile par l’influence des vaisseaux sanguins et les variations de la conductivité thermique, compliquant la planification spécifique à un patient donné. En fournissant des outils prédictifs, les modèles biophysiques pourraient aider les cliniciens à planifier et guider efficacement la procédure. Nous introduisons un modèle mathématique détaillé des mécanismes impliqués dans l’ARF des tumeurs du foie comme la diffusion de la chaleur et la nécrose cellulaire. Il simule l’étendue de l’ablation à partir d’images médicales, d’après lesquelles des modèles personnalisés du foie, des vaisseaux visibles et des tumeurs sont segmentés. Dans cette thèse, une nouvelle approche pour résoudre ces équations basée sur la méthode de Lattice Boltzmann est introduite. Le modèle est d’abord évalué sur des données de patients qui ont subi une ARF de tumeurs du foie. Ensuite, un protocole expérimental combinant des images multi-modales, anatomiques et fonctionnelles pré- et post-opératoires, ainsi que le suivi de la température et de la puissance délivrée pendant l'intervention est présenté. Il permet une validation totale du modèle qui considère des données les plus complètes possibles. Enfin, nous estimons automatiquement des paramètres personnalisés pour mieux prédire l'étendu de l’ablation. Cette stratégie a été validée sur 7 ablations dans 3 cas cliniques. A partir de l'étude préclinique, la personnalisation est améliorée en comparant les simulations avec les mesures faites durant la procédure. Ces contributions ont abouti à des résultats prometteurs, et ouvrent de nouvelles perspectives pour planifier et guider l’ARF. / The outcome of radiofrequency ablation (RFA) of abdominal tumors is challenged by the presence of blood vessels and time-varying thermal conductivity, which make patient-specific planning extremely difficult. By providing predictive tools, biophysical models may help clinicians to plan and guide the procedure for an effective treatment. We introduce a detailed computational model of the biophysical mechanisms involved in RFA of hepatic tumors such as heat diffusion and cellular necrosis. It simulates the extent of ablated tissue based on medical images, from which patient-specific models of the liver, visible vessels and tumors are segmented. In this thesis, a new approach for solving these partial differential equations based on the Lattice Boltzmann Method is introduced. The model is first evaluated against clinical data of patients who underwent RFA of liver tumors. Then, a comprehensive pre-clinical experiment that combines multi-modal, pre- and post-operative anatomical and functional images, as well as the interventional monitoring of the temperature and delivered power is presented. This enables an end-to-end validation framework that considers the most comprehensive data set for model validation. Then, we automatically estimate patient-specific parameters to better predict the ablated tissue. This personalization strategy has been validated on 7 ablations from 3 clinical cases. From the pre-clinical study, we can go further in the personalization by comparing the simulated temperature and delivered power with the actual measurements during the procedure. These contributions have led to promising results, and open new perspectives in RFA guidance and planning.

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