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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.
521

Biopolitique et barrières frontalières : le cas des frontières de l'Inde / Biopolitics and border barriers : the case of the Indian borders

Didiot, Marie 09 December 2015 (has links)
Loin de disparaître dans le cadre de la mondialisation des échanges, les frontières de l’Union indienne s’effacent devant certains flux pour se manifester vivement devant les flux jugés indésirables. Parallèlement au renforcement des contrôles des passages transfrontaliers, trois des six dyades de l’Union indienne font l’objet d’une teichopolitique, c’est-à-dire de la construction d’une barrière frontalière. Ces trois barrières ont pour objectif de réorienter tous les flux vers des points de passage où un tri est effectué entre les flux qui peuvent entrer sur le territoire et ceux qu’il convient de refouler. Les flux sont ainsi hiérarchisés en fonction de leur degré de désirabilité. Ils sont alors traités de manière différentielle en fonction des risques qu’ils représentent pour la sécurité de la société indienne. Les principaux flux indésirables sont les migrations clandestines, les trafics illicites et illégaux et les mouvements d’activistes dont les projets vont à l’encontre des intérêts indiens. L’hypothèse principale de cette thèse est que les trois barrières frontalières érigées par le gouvernement indien depuis le début des années 2000 sont des dispositifs biopolitiques dans la mesure où leur objectif est de filtrer les flux pour empêcher les entrées indésirables sur le territoire indien. Bien plus, ces barrières sont les manifestations de la radicalisation contemporaine du biopouvoir indien. L’objectif de cette thèse est d’appliquer une réflexion biopolitique à l’analyse des barrières frontalières indiennes et de poser les bases d’un système explicatif de ces phénomènes. Cette recherche a été initiée afin de mieux appréhender la théorisation de ces objets géographiques et géopolitiques. / Far from disappearing in the era of globalization, Indian Union borders are no longer policed against some immigration flows; conversely, they have been tightened against other unwelcome flows. In parallel with the reinforcement of cross-border flow controls, three of the six Indian land borders have been subjected to teichopolitics, that is to say the erection of border barriers. The aim of these border barriers is to redirect all the cross-border flows towards checkpoints, where they are sorted into different groups, namely those that are allowed in and those that are to be rejected. Thus prioritized in terms of social desirability, they are dealt with according to the risks they represent for Indian society. The main unwelcome flows are induced by clandestine migrants, traffickers and activists, whose plans can run counter to Indian interests. The main hypothesis of this research is that the three border barriers created by the Indian government since the beginning of the millenium are biopolitical devices. Indeed, their objective is to filter cross-border flows to prevent the unwelcome from entering the Indian territory. Moreover, these barriers manifest the contemporary radicalisation of Indian biopower. The aim of this thesis is to apply a biopolitical approach to the analysis of Indian border barriers and to propose an explanatory system for the understanding of this geopolitical phenomenon. This research was initiated in order to evolve a theory concerning these geographical and geopolitical factors.
522

The effect of methamphetamine on the blood-testis barrier

Zabida, Omer Saleh January 2018 (has links)
>Magister Scientiae - MSc / Introduction The blood-testis barrier (BTB) is formed by tight junctions between adjacent Sertoli cells. The barrier formed by these tight junction helps to create a specialized environment for spermatogenesis and provide an immunological barrier to protect developing germ cells. Methamphetamine (Meth) is known as neurotoxin however, its effects on the male reproductive system, especially on Sertoli cells and, the BTB are not well established. Therefore, this study aimed to determine the effects of Meth on the TM4 mouse testis Sertoli cell line and on the integrity of the BTB permeability. Materials and Methods This study investigated the effect of selected concentrations of Meth (0.1 μM, 1 μM, 10 μM, 20 μM and 100 μM) on TM4 mouse testis Sertoli cell line for 24 until 96 hours, using two treatments: an “acute” study (24 hrs exposure) and a “chronic” study, where treatment occurred on a daily basis over 96 hrs. The following parameters were investigated: viability, cell proliferation, mitochondrial activity, monolayer permeability.
523

Modeling and Evaluating the Thermal Conductivity of Porous Thermal Barrier Coatings at Elevated Temperatures for Industrial Applications

Alotaibi, Moteb 19 August 2019 (has links)
The thermal conductivity of various porous thermal barrier coating (TBC) systems used in elevated temperature for industrial applications has been evaluated using a proposed six-phase model. These porous TBC systems rely on microstructural properties and yield different types of porosity. These microstructural properties can influence the thermal conductivity of TBC systems. The purpose of this thesis is to assess the thermal conductivity of TBC systems based on microstructural attributes, particularly the effect of different types of porosity. Thus, the first component of this thesis investigates the microstructural characterization of various TBC systems using image analysis (IA) technique. In this technique, scanning electron microscopy (SEM) and light optical microscopy (LOM) micrographs were used to measure the porosity level of different TBC materials. The volumetric fraction of porosity along with orientation, shape, and morphology have a considerable impact on the total thermal conductivity of TBCs. The second component of this thesis evaluates the thermal conductivity of these porous TBC systems by taking into account the effect of the heat treatment process. The IA results reveal that as long as the porosity content increases, the thermal conductivity decreases for all of the TBC materials studied in this thesis. Further, while the content of microcracks and non-flat porosity play a crucial role in reducing the thermal conductivity of TBC materials, the other types of porosity (open randomly oriented, penny-shaped, and interlamellar) exert less impact on the thermal conductivity of TBCs. Comparing the results of the proposed six-phase model to experimental values and finite element analysis (FEA) values showed a relatively good agreement. The proposed six-phase model can predict the thermal conductivity of porous microstructure of TBC systems close to real measured values; therefore, the proposed six-phase model may be utilized to fabricate the porous microstructure of TBCs.
524

Tvärkulturella möten inom hälso- och sjukvården : En litteraturöversikt ur patientperspektivet / Cross-cultural encounters in healthcare : Literature review from the patients’ perspective

Bäckström, Lyupka January 2019 (has links)
Bakgrund: Möten med olika människor inom hälso- och sjukvården innebär också möten mellan människor med olika kulturell bakgrund, kunskaper och som talar olika språk. Antalet patienter som söker vård och inte delar samma språk eller kultur med sin vårdgivare och omvänt ökar kontinuerligt. Syfte: Syftet var att beskriva erfarenheter av mötet med västerländsk hälso- och sjukvård för patienter med annan kulturell bakgrunden för att öka förståelsen och ge kunskaper som kan minska, ändra eller lindra möjliga negativa effekter av dessa möten. Metod: För att besvara studiens syfte användes litteraturöversikt med induktiv ansats. Resultat: Tre kategorier: Kommunikation och kommunikationsrelaterade aspekter, Hälso- och sjukvårdsrelaterade aspekter och kultur och kulturrelaterade aspekter. Konklusion: Studien visar att även då en del av patienterna upplever att tvärkulturella möten inom hälso- och sjukvården anses vara bra så finns också luckor och möjligheter till förbättringar inom vårdande kommunikation och kulturell anpassad omvårdnad. Brister i kulturellt anpassad kommunikation och omvårdnad lämnar patienterna att känna frustration, rädsla, sårbarhet, hjälplöshet och skam. Detta i sin tur leder till att patienternas förtroende och delaktighet i hälso- och sjukvården minskar och därför är det viktigt att det uppmärksammas. / Background: Encounters with different people in the healthcare also means encounter between people who have different cultural background, skills and speak different languages. The number of patients that seek healthcare and don’t share same language and culture with their caregiver and vice versa is increasing continuously. Aim: The purpose was to describe the experiences in encounters with Western healthcare for patients with a different cultural background with the purpose to increase the understanding and knowledge that can reduce, alter or ease possible negative effects of these encounters. Method: Literature review with inductive approach was used. Result: Three categories: Communication and communication related aspects, Healthcare and healthcare related aspects and culture and culturally related aspects. Conclusion: The study shows that even though one part of the patients feel that cross-cultural encounters in healthcare are considered to be good, there are also gaps and opportunities for improvements in healthcare communication and culturally adapted healthcare. Inadequacy in culturally adapted communication and healthcare leave patients to feel helpless, frustrated, fearful, vulnerable and ashamed. This, in turn, leads to a reduction in patient confidence and participation in healthcare, which is why it is important to pay attention to.
525

Uma adaptação do método barreira penalidade quasi-Newton ao problema de fluxo de potência ótimo /

Campanha, Paulo Sérgio. January 2011 (has links)
Resumo: Nesse trabalho propõe-se uma adaptação do método barreira penalidade quasi-Newton apresentado por P. Armand em 2003, para a resolução do problema do Fluxo de Potência Ótimo (FPO). Este método é denominado de método da função langrangiana barreira penalidade adaptada. Neste método as restrições de desigualdade são transformadas em igualdade pelo uso de variáveis de folga positivas. Estas variáveis são relaxadas, utilizando-se variáveis positivas, as quais, são incorporadas na função objetivo através de um termo de penalização. O novo problema restrito é então transformado em irrestrito associando a uma função lagrangiana às restrições de igualdade e uma função barreira penalidade às restrições de desigualdade. o algoritmo é composto por um ciclo interno e um externo. No ciclo interno é utilizado um método quasi-Newton para o cálculo das direções de busca e é determinado o tamanho do passo. No ciclo externo os parâmetros de barreira e penalidade são atualizados através de regras pré-definidas até que as condições de KKT sejam satisfeitas. Testes computacionais foram realizados utilizando problemas matemáticos e o problema de FPO, os quais demonstram a eficiência da adaptação proposta / Abstract: This work proposes an adaptation of the quasi-Newton penalty barrier method presented by P. Armand in 2003. for the solution of the Optimal Power Flow (OPD) problem. This method is called method adapted penalty barrier lagrangian function. In this method the inequalities constraint are transformed in equality by adding non-negative slack variable. These variables are relaxed by positive auxiliary variables which are incorporated in the objective function through a penalty term. The new constraint problem is transformed in unconstraint by associating an lagrangian function for handling the equality constraint and an penalty barrier function for treating the inequality constraints. The algorithm is composed by an internal and external cycle. In the interanal cycle is used the quasi-Newton method to determine the search directions and the step size is calculated. In the external cycle the barrier parameters are updated through predefined rules until the KKT conditions are satisfied. Computational tests were accomplished using mathematical problems and the OPF problem which demonstrate the efficiency of the propose adaptation / Orientador: Edméa Cássia Baptista / Coorientador: Vanusa Alves de Sousa / Banca: Geraldo Roberto Martins da Costa / Banca: Antonio Roberto Balbo / Mestre
526

Conversion Rate Optimization : A Qualitative Approach to Identifying Optimization Barriers / Konverteringsoptimering : En kvalitativ strategi för att identifiera optimeringsbarriärer

Jensen, Marina January 2019 (has links)
This thesis examined the question “What barriers are preventing Swedish companies from performing a structured conversion rate optimization process?”. As the purpose is to obtain an understanding of what is preventing companies from successfully execute conversion rate optimization (CRO). Given that CRO is an important part in most digital marketing activities. And despite increase in budget and importance in marketing, resource constraint continues to be the biggest obstacle.  The method employed to investigate this question was qualitative interviews with participants who worked with websites in seven different companies. An analysis was carried out, estimating the participating companies’ level of knowledge, overall structure, what to prioritize and current obstacles. It was established that the interviewees had several different areas of concern with regards to conversion rate optimization. Limited time, budget, priorities, knowledge, ownership, structured approach and interpreting data, were all treated in the analysis. A discussion was carried out to argument the definition of “biggest” barrier, as some barriers were more common than others but easier to overcome. Overall, these obstacles could all be traced back to barriers as prioritization, structure and ownership. The conclusion was that companies must have a more structured working process within the area of conversion rate optimization in order for this practice to be prioritized as a substantial part of companies online marketing activities. / Denna uppsats har undersökt frågan "Vilka hinder hindrar svenska företag från att genomföra en strukturerad konverteringsoptimerings process?". Med syfte att få en förståelse för vad som hindrar företagen att utföra konverteringsoptimering (CRO). Då CRO är en viktig del i de flesta digitala marknadsaktiviteter. Och trots ökad budget och kunskap inom marknadsföring är resursbegränsningen fortfarande det största hindret. Metoden som användes för att undersöka denna fråga var kvalitativa intervjuer med deltagare som arbetade med webbplatser inom sju olika företag. En analys genomfördes, som tog upp företags kunskapsnivå, övergripande struktur, prioriteringar och nuvarande hinder. Det fastställdes att intervjuarna hade flera olika problemområden med avseende om konverteringsoptimering. Begränsad tid, budget, prioriteringar, kunskap, ägandeskap, strukturerat abetsflöde och tolkning av data, behandlades alla i analysen. En diskussion gjordes för att argumentera för definitionen av "största" barriären, eftersom vissa hinder var vanligare än andra men lättare att övervinna. Sammantaget kan dessa hinder alltså spåras tillbaka till hinder som prioritering, struktur och ägande. Slutsatsen var att företagen måste ha en mer strukturerad arbetsprocess inom området för konverteringsoptimering för att denna disciplin ska prioriteras som en väsentlig del av företagets marknadsföringsaktiviteter online.
527

Placentação em roedores da família Cricetidae - Sigmodontinae / Placentation in rodents of family Cricetidae Sigmodontinae

Favaron, Phelipe Oliveira 02 June 2009 (has links)
A placenta é encontrada apenas em mamíferos, e é resultado do sucesso da implantação do blastocisto no útero, representando um órgão funcional de trocas materno-fetais, sendo também um importante órgão endócrino. Na família Cricetidae e Subfamília Sigmodontinae englobam os ratos e camundongos da América do Sul. Devido à semelhança entre a morfologia da placenta e o processo de placentação dos roedores com a placenta humana, estes animais representam um interessante modelo para estudos relacionados à placentação. O objetivo deste estudo foi descrever a morfologia da placenta e a placentação em 5 espécies de sigmodontes (Necromys lasiurus, Oryzomys subflavus, Oryzomys sp., Oryzomys megacephalus e Oligoryzomys sp.). Nas análises macroscópicas constatou-se que a placenta desse grupo apresenta um formato discóide, sendo classificada como zonária discoidal. Na microscopia observou-se que a placenta é do tipo corioalantóidea, labiríntica, hemocorial, com zonas de espongiotrofoblasto e uma região de decídua materna. A placenta vitelina é vilosa, completamente invertida e persistia até o final da gestação. Somente em Oryzomys subflavus foi observada na placenta vitelina uma intensa atividade hemofágica, evidenciada pela técnica de Tricrômo de Masson. A barreira placentária nas espécies Necromys lasiurus e Oryzomys sp. é do tipo hemotricorial, existindo três camadas trofoblásticas adjuntas ao endotélio do capilar fetal separando os sistemas sanguíneos materno e fetal. As células trofoblásticas gigantes foram observadas em diferentes regiões da placenta. Em todas as espécies as células deciduais foram positivas para reação histoquímica de ácido periódico de Schiff (P.A.S.). / Placenta is found only in mammals and it is result of the success of blastocyst implantation in the uterus, representing a functional organ to maternal-fetal exchanges and it is also an important endocrine organ. The Family Cricetidae and Subfamily Sigmodontinae include the rats and mice from South America. Due to the similarity of both the placenta morphology and the placentation between rodents and human, these animals represent an interesting model for studies related to the placenta and placentation. The aim of this research was to describe the placenta morphology and placentation in 5 species of sigmodonts (Necromys lasiurus, Oryzomys subflavus, Oryzomys sp., Oryzomys megacephalus Oryzomys sp. and Oligoryzomys sp.). In the macroscopic analysis the placenta shows a discoid shape, it is classified as discoid type. The microscopy results showed the placenta is chorioallantoic, labyrinth, hemochorial, with areas of spongio zone and a region of maternal decidua. The yolk sac placenta is villous, completely inverted and persisted until the end of pregnancy. Only in Oryzomys subflavus was observed in the yolk sac placenta an intense hemophagous activity, evidenced by the Masson\'s trichrome stain. The placental barrier in Necromys lasiurus and Oryzomys sp. is of the hemotrichorial type, composed by three trophoblast layers more the fetal capillary endothelium to separate the maternal and fetal blood systems. The trophoblast giant cells were observed in different regions of the placenta. In all species the decidual cells were positive to histochemical reaction using periodic acid-Schiff (PAS).
528

Ressonâncias Stark e tunelamento em heteroestruturas semicondutoras. / Stark resonances and quantum tunnel effect in semiconductor heterostructures.

Cury, Luiz Alberto 15 September 1987 (has links)
Neste trabalho determinamos a estrutura dos níveis dos estados quase-ligados e virtuais em sistemas de poços quânticos acoplados de AlGaAs-GaAs na presença de um campo elétrico externo (Voltagem) perpendicular às camadas semicondutoras. As heteroestruturas de AlGaAs-GaAs são modeladas por um conjunto de poços quânticos de potencial unidimensionais. Utilizamos a aproximação de função envelope que reduz o problema à solução usual da Equação de Schroedinger de massa efetiva. Os níveis eletrônicos são então determinados utilizando a solução exata da Eq. de Schroedinger em termos das funções de Airy nos poços e barreiras e um formalismo de Matriz de Iteração com Análise de \"Phase-shift\". Nossos resultados estão em boa concordância com resultados experimentais de transições ópticas. Motivados pelas propriedades singulares dos sistemas de dupla barreira, investigamos o tunelamento ressonante de elétrons através de multi-barreiras e a formação de regiões de resistência negativa na curva característica de corrente X voltagem. Para os processos de tunelamento em multi-barreiras determinamos o Coeficiente de Transmissão, como função da energia do elétron incidente, usando o formalismo de Matriz de Iteração. Este método pode ser bastante útil na interpretação de resultados experimentais nestes dispositivos. Calculamos também a densidade de corrente de tunelamento versus a voltagem aplicada no caso de dupla barreira de modo a interpretar recentes resultados experimentais. / In this work the quasi-bound and virtual levels of both electrons and holes are determined in the case of coupled AlxGa1-xAs-GaAs quantum wells in the presence of an external electric (Voltage) perpendicular to the layers. The heterostructures field of AlxGa1-xAs-GaAs are mimicked by a set of unidimensional quantum well potentials. We employ the envelope function approximation and solve the usual effective mass Schrödinger Equation. The electronic levels are then determined by using the exact solution of Schrödinger Eq. in terms of Airy functions into the wells and barriers and an Iteraction Matrix formalism with the Phase-shift method. Our results are in a good agreement with the experimental results of optical measurements. Motivated by the unusual properties of double-barriers devices we investigated the resonant tunneling of electrons through multi-barriers. The transmission Coefficient as a function of energy of the incident electron is determined by using an Interaction Matrix formalism. This method can be very useful in the interpretation of experimental results in semiconductor devices. We also calculate the tunneling current density as a function of applied voltage in the case of a double-barrier in order to interpret recent experimental results.
529

Alterações da barreira e da microbiota intestinais na caquexia associada ao câncer de cólon. / Alterations of the intestinal barrier in caquexia associated with colon cancer.

Costa, Raquel Galvão Figuerêdo 20 July 2018 (has links)
A caquexia é uma síndrome multifatorial e multiorgânica associada ao câncer e outras doenças crônicas e caracterizada por perda involuntária grave de massa corporal, metabolismo e função imune alteradas, anorexia, fadiga e diminuição da qualidade de vida. A caquexia afeta cerca de 50% dos pacientes com câncer de cólon e é diretamente responsável pela morte de pelo menos 20% de todos os pacientes com câncer. A inflamação sistêmica, resultante da produção de mediadores inflamatórios, é comumente observada na caquexia do câncer. É possível que a inflamação possa derivar em parte da falha da função de barreira intestinal, promovendo uma ativação imunológica persistente. Este estudo envolveu 45 pacientes, divididos em grupos: WSC (câncer de peso estável) e CC (câncer com caquexia) e investigou a inflamação do cólon e a composição da microbiota intestinal na caquexia. Para tanto, realizou-se uma análise histológica por microscopia de luz e quantificação de fatores inflamatórios por Luminex® xMAP em biópsias de cólon retossigmóide (20 cm distantes do sítio tumoral) obtidas de pacientes CC e WSC durante a cirurgia para a retirada de tumor. Adicionalmente, realizou-se o seqüenciamento genético para a análise da composição da microbiota presente nas fezes dos pacientes. O número de agregados linfóides, eosinófilos e fibroblastos foi maior na mucosa do cólon em CC do que em WSC. A expressão da interleucina 7 (IL-7), da interleucina 13 (IL-13) e do fator de crescimento transformador beta 3 (TGF- &#946 3) aumentou significativamente no CC, em comparação com o WSC. Houve uma redução de bactérias dos gêneros Anaerotipes, Dorea e Coprococcus nos pacientes do grupo CC. Por outro lado, houve um aumento de bactérias dos gêneros Gemella e Parvimonas nos pacientes CC, comparado aos pacientes WSC. Os resultados sugerem alterações na barreira intestinal dos pacientes caquéticos, com um aumento do recrutamento de células imunes na mucosa do cólon, resposta inflamatória e de reparo teciduais. Não está claro se as respostas locais podem ser dirigidas pela disbiose ou podem promover a disbiose. Compreender o papel do intestino e da microbiota intestinal na patogênese desta síndrome pode levar ao desenvolvimento de novos alvos terapêuticos, a fim de minimizar a inflamação intestinal e os sintomas da caquexia. / Cachexia is a multifactorial and multiorgan syndrome associated with cancer and other chronic diseases and characterised by severe involuntary loss of body weight, disrupted metabolism, altered immune function, anorexia, fatigue and diminished quality of life. Cachexia affects around 50% of patients with colon cancer and is directly responsible for the death of at least 20% of all cancer patients. Systemic inflammation, the result of the production of inflammatory mediators, is commonly observed in cancer cachexia. It is possible that inflammation may partly derive from the failure of gut barrier function, yielding persistent immune activation. This study involved 45 patients, divided into groups: WSC (Weight Stable Cancer) and CC (Cachectic Cancer) and investigated the inflammation of the colon and the composition of the intestinal microbiota in cachexia. For this purpose, we carried out a morphological analysis by light microscopy and quantification of inflammatory factors by Luminex® xMAP in rectosigmoid colon biopsies (20 cm distant from the tumour site) obtained from cachectic (CC) and weight stable (WSC) colon câncer patients, during surgery. In addition, the genetic sequencing was performed to analyze the composition of the microbiota in the faeces of the patients. The number of lymphocytic aggregates, eosinophils and fibroblasts was higher in the mucosa of the colon in CC than in WSC. In regard to inflammatory cytokines, interleukin 7 (IL-7), interleukin 13 (IL-13) and transforming growth factor beta 3 (TGF- &#946 3) protein expression was significantly increased in CC, compared with WSC. There was a reduction of bacteria of the genus Anaerotipes, Dorea and Coprococcus in CC. On the other hand, there was an increase of bacteria of the genus Gemella and Parvimonas in CC patients, compared to WSC patients. The results suggest alterations in the intestinal barrier in cachectic patients, with an increase in the recruitment of immune cells in the mucosa of the colon, orchestrating an inflammatory response and in tissue repair. It is not clear whether local responses can be driven by dysbiosis or if it could promote dysbiosis. Understanding the role of the intestine and intestinal microbiota in the pathogenesis of this syndrome may lead to the development of new therapeutic targets in order to minimize intestinal inflammation and the symptoms of cachexia.
530

Développement de formulations polymériques de S-nitrosoglutathion comme traitement per os pour prévenir les maladies inflammatoires chroniques de l’intestin / Development of S-nitrosoglutathione loaded particles adapted to oral administration for preventing Inflammatory Bowel Disease relapses

Ming, Hui 07 December 2017 (has links)
Les maladies inflammatoires chroniques de l’intestin (MICI) représentent un problème de santé publique majeur touchant de jeunes patients. Aux récidives inflammatoires, à la mauvaise qualité de vie et à l’espérance de vie réduite des patients viennent s’ajouter la durée, l’efficacité parfois limitée et le coût des traitements actuellement proposés. La recherche de nouvelles stratégies permettant de prévenir les récidives inflammatoires est primordiale. Ainsi, le rôle du S-nitrosoglutathion (GSNO, donneur et forme de stockage naturelle de NO) dans le maintien de l’intégrité de la barrière intestinale est étudié dans cette thèse, en décrivant : i) l’effet concentration-dépendante du GSNO sur la perméabilité intestinale (modèle de chambre de Ussing, expression des protéines de jonctions cellulaires…), ii) des formulations innovantes de GSNO (nanoparticules composites) à base de nanoparticules d’Eudragit®RL, elles-mêmes encapsulées dans une matrice polymérique à base d’alginate. Différents procédés de formulation ont été testés. Une caractérisation physicochimique des objets développés et des études de perméabilité sur des modèles cellulaires (Caco-2) ont conduit à l’obtention de trois formulations, adaptées à la voie orale et permettant de délivrer de façon prolongée le GSNO. Cependant, la prise en charge du GSNO libre ou formulé, l’identification des cibles du NO au niveau intestinal, mais aussi les doses et durées du traitement in vivo restent encore à définir avant de proposer ce donneur de NO comme candidat pour un traitement préventif des MICI / Inflammatory bowel diseases (IBD) (Crohn’s disease, ulcerative colitis…), are disabling pathologies affecting young patients and presenting the particularity that most of the current agents act by down regulating chronic inflammation in the intestine mucosa and cannot cure the disease. As the pivotal role of S-nitrosoglutathione (GSNO) in preventing intestinal inflammation and gut barrier failure has been clearly pointed out, therapies based on pharmaceutical technology to limit chronic inflammation and prevent relapses of barrier failure by an optimized dosage form of GSNO appears as an interesting challenge. The objective of this project relies on i) studying GSNO concentration/response functions in intestine by using Ussing chamber ex vivo model and following protein cell junction expression, ii) developing polymer nanocomposite particles encapsulating GSNO and adapted to the oral route, with GSNO protection, controlled delivery and local effect in intestine as major requirements. GSNO loaded polymeric (Eudragit® RL) nanoparticles were included in polymer matrix based on alginate; different processes were tested and particles were characterized: high GSNO loading, GSNO sustained release and local retention for 4 h in cellulo study (Caco-2) were obtained. Thus, therapies based on GSNO administration should represent a novel strategy to limit chronic inflammation and prevent relapses of barrier failure in IBD patients

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