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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.
61

Atividade antibacteriana do óleo essencial de Citrus limon frente cepas multidroga resistentes do gênero Acinetobacter.

Guerra, Felipe Queiroga Sarmento 14 February 2012 (has links)
Made available in DSpace on 2015-05-14T12:59:32Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 730230 bytes, checksum: c9ea66b757014e0b2d6d2b07b2de3af1 (MD5) Previous issue date: 2012-02-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Acinetobacter species have gained importance in recent years due to their increased involvement in serious infections and antimicrobial resistance. Since multidrug resistant bacteria pose a challenge to the treatment of infections, it is necessary to find new substances with antimicrobial properties in combating these microorganisms. Thus, medicinal plants are studied, since they are used for treatment of various illnesses. Therefore, many studies on biological activity have been performed with essential oils obtained from medicinal plants, such as the essential oil from Citrus limon (EOCL), attempting to help overcome this problem. Thus the present study aimed to evaluate the effect of the essential oil of EOCL against multidrug resistant strains of Acinetobacter spp. Its chemical composition was determined by GC/MS and its antibacterial activity was assessed by determining their MIC and MBC by microplate bioassay, its Time kill too was determinated. Also was analyzed the effect of modulating action of conventional antibiotics by microplate bioassay. Among phytochemicals, Neral (29.4%) presented as the major essential component of EOCL. The oil caused growth inhibition in 16 (67%) of 24 strains tested, showing a MIC of 625 μg/ml and MBC of 1250 μg/mL. In a time kill study, the oil displayed a concentration-dependent antibacterial activity. Results of combining antibiotics and EOCL had shown us a synergistic and additive effect with EOCL /antibiotics combinations. The results of this study suggest that essential oil of C. limon may suppress the growth of Acinetobacter species and could be a source of metabolites with modified antibacterial activity. / Espécies do gênero Acinetobacter ganharam importância nos últimos anos devido ao seu envolvimento crescente em infecções graves e resistência antimicrobiana. Uma vez que bactérias resistentes a múltiplas drogas representam um desafio para o tratamento de infecções, é necessário encontrar novas substâncias com propriedades antimicrobianas no combate a estes microrganismos. Para tentar superar este panorama, várias pesquisas vêm sendo desenvolvidas em busca de novos produtos antibacterianos, dentre elas estão os estudos com os metabólitos de plantas, como o óleo essencial de Citrus limon (OECL). Assim, o presente estudo teve como objetivo avaliar o efeito do óleo essencial de Citrus limon contra cepas de Acinetobacter multidroga resistentes. Sua composição química foi determinada por CG/EM e sua atividade antibacteriana avaliada pela determinação de sua CIM e CBM pela técnica de microdiluição, sua cinética de morte microbiana também foi analisada. Verificou-se também seu efeito modulador da ação dos antibióticos convencionais por técnicas de microdiluição. Entre os fitoconstituintes, neral (29,4%) apresenta-se como o principal componente de OECL. O referido óleo inibiu o crescimento de 67% das 24 cepas ensaiadas, tendo sua CIM estabelecida em 625 μg/mL e a CBM em 1250 μg/mL Este óleo possui atividade antibacteriana dependente de sua concentração e do tempo de exposição no microrganismo e é um modulador da ação dos antibióticos convencionais. Os resultados deste estudo sugerem que o referido óleo pode suprimir o crescimento de espécies de Acinetobacter e poderia ser uma fonte de metabólitos com atividade modificadora antibacteriana.
62

El uso de adjetivos pre- y posnominales en  el discurso coloquial de hablantes no nativos / Non-native speakers’ use of post-nominal and pre-nominal adjectives in colloquial speech

Wikström, Joakim January 2018 (has links)
El propósito de la presente monografía es investigar si un grupo de hablantes no nativos de español, todos de nivel muy avanzado, usan los adjetivos modificadores en su discurso espontáneo de una manera parecida a la nativa, y más particularmente en qué medida los colocan de manera idiomática delante o detrás del substantivo. El material usado consiste, por un lado, de entrevistas, en las cuales los participantes cuentan de sus propias vidas, y por el otro lado, de una tarea en la que comentan la acción en un videoclip de la película Tiempos Modernos (de Charlie Chaplin). Los participantes del estudio son diez suecos que residen en Chile desde hace por lo menos 5 años. La hipótesis es que, dada una constatada tendencia conservadora general en los hablantes de una segunda lengua que los llevaría a “ir por lo seguro“, los sujetos sobreusarían la opción no marcada, o sea, la posposición, en la colocación de los adjetivos. Los adjetivos están categorizados en dos grupos: uno de adjetivos cotidianos que tienden a anteponerse al sustantivo (bueno, malo, pequeño, grande, pobre, puro, nuevo, viejo, alto), y los restantes adjetivos, que por defecto aparecen en posición posnominal (p.ej. laboral, sueco, libre, desnudo, rápido, cultural, blanco, redondo, privado etc.). Los resultados no apoyan la hipótesis, en el sentido de que los participantes no nativos tienden a sobreusar la posposición. Estos participantes son comparados con un grupo de control que consiste de diez hablantes de español L1 que residen en Chile. Un aspecto que discrepa en el grupo de hablantes no nativos es el uso del adjetivo grande, para el cual los no nativos prefieren la posposición. También destaca el hecho que los participantes nativos son más propensos a usar adjetivos en general en comparación con el grupo no nativo. / The purpose of this thesis is to investigate to what extent a group of non-native Spanish speakers, all of whom are highly proficient users of L2 Spanish, use modifying adjectives in spontaneous discourse in a targetlike manner and, particularly, to what extent they place them idiomatically before or after the noun. The corpus used consists of interviews, in which the subjects talk about their lives, and another task in which they comment the action of a videoclip from the movie ‘Modern Times’ (by Charlie Chaplin). The subjects of the study are ten Swedes that have lived in Chile for at least 5 years. The assumption being the tendency for second language speakers to be generally conservative and choose to ‘go for what's safe’, it is hypothesized that the L2 users would overuse the unmarked option for placing adjectives, namely after the noun. The adjectives are divided into two categories: one consisting of everyday adjectives that strongly tend to be placed ahead of the noun (bueno, malo, pequeño, grande, nuevo, pobre, puro, viejo, alto) and the other of adjectives that appear in postposition by default (e.g. laboral, sueco, libre, desnudo, rápido, cultural, blanco, redondo, privado etc.). The results don’t support the hypothesis, in the sense that the non-native participants tend to overuse postposition. The L2 participants have been compared to a control group consisting of ten L1 Spanish speakers living in Chile. One aspect that differs in the non-native group is the use of grande, for which the non-native speakers, unlike the natives, prefer postposition. What also stands out is the fact that native speakers are more prone to using adjectives in general compared to the non-native group.
63

Impacto dos medicamentos imunobiológicos e da doença coronária na evolução de pacientes com artrite reumatoide: uma análise de custo-efetividade / Impact of immunobiological drugs and coronary disease evolution of patients with rheumatoid arthritis: a cost-effectiveness analysis

Rafael Kmiliauskis Santos Gomes 02 June 2017 (has links)
Introdução: Estudos epidemiológicos têm estabelecido que a artrite reumatoide está associada com um aumento de doença cardiovascular. A avaliação de anti-TNF sobre a redução do risco de infarto agudo do miocárdio e óbito por causa cardiovascular tem demonstrado resultados promissores. A avaliação econômica para esses desfechos ainda não está estabelecida. Objetivo: Realizar uma análise de custo efetividade de anti-TNF versus Dmards para evitar um caso novo de morbidade e óbito cardiovascular na artrite reumatoide. Método: Foi realizada uma análise de custo efetividade por meio do modelo de Markov, ciclo de transição de 6 meses e horizonte temporal de 30 anos sob perspectiva do sistema público de saúde do Brasil mensurado pela razão de custo efetividade incremental. Custo em Reais no ano de 2015 e efetividade em evitar um caso novo de doença coronariana isquêmica aguda e óbito cardiovascular. Resultados: O custo médio em 30 anos de Dmards e anti-TNF foi de R$ 14.291.105,28 e R$ 96.151.873,86, respectivamente. A efetividade incremental para doença arterial coronariana foi de 2,69 e consequente razão incremental de custo efetividade de R$ 30.527.502,27, enquanto para óbito cardiovascular a efetividade incremental foi de 1,33 casos evitados e uma razão incremental de custo efetividade de R$ 61.634.231,69. A análise univariada identificou que o parâmetro de maior impacto na razão incremental de custo efetividade de ambos os desfechos foi o medicamento anti-TNF. A análise de sensibilidade estabeleceu que, para atingir o valor de disposição a pagar por semestre para evitar um infarto agudo do miocárdio, o custo médio do anti-TNF deveria ser de R$ 1.337,47 ou diferença de incidência entre as estratégias de 0,032. Ainda, para evitar um óbito cardiovascular, o custo médio deveria ser de R$ 954,22 ou diferença de incidência de 0,071. Todas as análises realizadas estabeleceram uma relação desfavorável da estratégia do tratamento medicamentoso com anti-TNF. Conclusão: Os achados da análise de custo efetividade entre pacientes com artrite reumatoide para desfecho cardiovascular quando comparada a estratégia de tratamento medicamentoso de anti-TNF em relação à estratégia dominante com Dmards após os 6 primeiros meses de exposição aos medicamentos apontaram para uma relação desfavorável, ultrapassando o valor de disposição a pagar recomendado pelo Ministério da Saúde do Brasil no ano de 2015. Descritores: artrite reumatoide; doenças cardiovasculares; infarto do miocárdio; óbito; avaliação de custo-efetividade; anti fator de necrose tumoral; drogas anti-reumáticas modificadoras de doença. / Introduction: Epidemiological studies have established that rheumatoid arthritis is associated with an increase in cardiovascular disease. The evaluation of anti-TNF on the reduction of the risk of acute myocardial infarction and death due to cardiovascular causes has shown promising results. The economic evaluation for these outcomes is not yet established. Objective: To perform a cost-effectiveness analysis of anti-TNF versus Dmards to avoid a new case of cardiovascular morbidity and death in rheumatoid arthritis. Method: A cost effectiveness analysis was performed using the Markov model, a 6-month transition cycle and a 30-year time horizon under the perspective of the Brazilian public health system measured by the incremental cost-effectiveness ratio. Cost in Reais in the year 2015 and effectiveness in avoiding a new case of acute ischemic coronary disease and cardiovascular death. Results: The average cost in 30 years of Dmards and anti-TNF was R$ 14,291,105.28 and R$ 96,151,873.86, respectively. The incremental effectiveness for coronary artery disease was 2.69 and a consequent incremental cost-effectiveness ratio of R$ 30,527,502.27, while for cardiovascular death, incremental effectiveness was 1.33 cases avoided and an incremental cost-effectiveness ratio of R$ 61,634,231.69. The univariate analysis identified that the parameter of greatest impact in the incremental cost-effectiveness ratio of both outcomes was the anti-TNF drug. The sensitivity analysis established that the average cost of anti-TNF should be R$ 1,337.47 or incidence difference between strategies of 0.032 in order to reach the amount of willingness to pay per semester to avoid an acute myocardial infarction. Also, to avoid a cardiovascular death, the average cost should be R$ 954.22 or incidence difference of 0.071. All the analyzes carried out established an unfavorable relationship of the drug treatment strategy with anti-TNF. Conclusions: The findings of the cost-effectiveness economic analysis among individuals with rheumatoid arthritis for cardiovascular outcome when compared to the strategy of anti-TNF drug treatment compared to the dominant strategy with Dmards after the first 6 months of drug exposure pointed to an unfavorable relationship, surpassing the amount of willingness to pay recommended by the Ministry of Health of Brazil in the year 2015.
64

Energiewandlersystem für den Betrieb von autarken Sensoren in Fahrzeugen

Naumann, Gunther 19 December 2003 (has links)
Zur Verminderung der Kosten und zur Erhöhung der Zuverlässigkeit ist es zukünftig erforderlich, den Verkabelungsaufwand bei Sensoren im Kraftfahrzeug zu senken. Ein Ansatz ist der so genannte autarke Sensor, der seine Hilfsenergie drahtlos aus dem Umfeld gewinnt und seine gewonnen Messdaten ebenfalls drahtlos an einen Kommunikationspunkt überträgt. In der vorliegenden Dissertation wurde die autarke Energiegewinnung für Sensoren anhand mechanisch / elektrischer Energiewandlersysteme untersucht, die eine von Kabelverbindungen unabhängige Energieversorgung des Sensors ermöglichen sollen. Für ein System, welches aus einem translatorischen Schwinger mit magnetischer Federung und einer Anordnung von Induktionsspulen ohne Eisenkreis besteht, wurden theoretische und praktische Untersuchungen durchgeführt. Ausgehend von der, die Bewegung des Systems beschreibenden Differentialgleichung wurden die Einflüsse verschiedener Federungs- und Dämpfungskräfte untersucht. Daraus wurde eine effektive Schwingungsgleichung abgeleitet und hinsichtlich der Amplitude und der Phase gelöst. Die umgesetzte elektrische Leistung des Wandlers wurde aus dem Realteil des Stromflusses abgeleitet. Mit einem realen Fahrzeug wurden Testfahrten durchgeführt, um verschiedene signifikante Fahrbahndaten zu erhalten. Mit diesen Prozessparametern erfolgten später Messungen im Labor. Dafür wurde ein Schwingprüfstand aufgebaut und mehrere Funktionsmuster von Energiewandlersystemen untersucht. / In the future a decrease in sensor cabling inside vehicles becomes of greater importance to reduce cost and increase reliability. One approach is the so called autarkic sensor that generates energy wireless from the sensor's environment and transmits the derived measuring data also wireless to a communication node. Purpose of this dissertation is to discuss the autarkic energy recovery sensors based on a mechanical to electrical conversion which should allow a cable less energy supply. Theoretical and practical tests where made for a system which consists out of a translatory vibration with magnetic suspension and coreless coils. Starting from the differential equations describing the movement of the system, the influence of different ways of suspension and damping forces where investigated. As a result, the actual equation of oscillation was derived and solved with respect to amplitude and phase. The gained electrical power was derived from the real part of the current. Multiple test runs inside a car where performed to obtain some realistic measurement values. Based on those measurements, a test stand was set up inside the laboratory which should simulate normal road conditions. Using this test stand, multiple functional models of energy converting systems were investigated.
65

Assemblage oligomérique des récepteurs couplés aux protéines G avec les RAMPs

Héroux, Madeleine 03 1900 (has links)
Les récepteurs couplés aux protéines G (RCPGs) constituent la plus grande classe de récepteurs membranaires impliqués dans la transmission des signaux extracellulaires. Traditionnellement, la transmission de la signalisation par les RCPGs implique l’activation d’une protéine G hétéro-trimérique qui pourra à son tour moduler l’activité de divers effecteurs intracellulaires. Ce schéma classique de signalisation s’est complexifié au fils des années et l’on sait maintenant qu’en plus d’interagir avec les protéines G, les RCPGs s’associent avec une panoplie d’autres protéines afin de transmettre adéquatement les signaux extracellulaires. En particulier, la découverte d’une famille de protéines transmembranaires modulant la fonction des RCPGs, baptisées protéines modifiant l’activité des récepteurs (« receptor activity-modifying proteins » ; RAMPs), a changé la façon de concevoir la signalisation par certains RCPGs. Dans le cas du récepteur similaire au récepteur de la calcitonine (« calcitonin-like receptor » ; CLR), l’association avec les RAMPs permet l’acheminement à la surface cellulaire du récepteur tout en modulant ses propriétés pharmacologiques. Lorsqu’il est associé avec RAMP1, le CLR fonctionne comme un récepteur du peptide relié au gène de la calcitonine (« calcitonin gene-related peptide » ; CGRP), alors qu’il devient un récepteur de l’adrénomedulline lorsqu’il interagit avec RAMP2 ou RAMP3. D’autre part, en plus d’interagir avec des protéines accessoires transmembranaires telles les RAMPs, les RCPGs peuvent aussi s’associer entre eux pour former des oligomères de récepteurs. Dans cette thèse, nous nous sommes penchés sur les interactions entre les RCPGs et les RAMPs, et plus particulièrement sur l’interrelation entre ce type d’association RCPG/RAMP et l’assemblage en oligomères de récepteurs, en utilisant le récepteur du CGRP comme modèle d’étude. Une première étude nous a tout d’abord permis de confirmer l’interaction entre le récepteur CLR et RAMP1, dans un contexte de cellules vivantes. Nous avons démontré que ce complexe CLR/RAMP1 active la protéine G et recrute la protéine de signalisation -arrestine suite à une stimulation par le CGRP. Ensuite, nous avons déterminé que même s’il doit obligatoirement former un hétéro-oligomère avec les RAMPs pour être actif, le CLR conserve malgré tout sa capacité à interagir avec d’autres RCPGs. En plus d’observer la présence d’homo-oligomère de CLR, nous avons constaté que tout comme les RCPGs, les RAMPs peuvent eux-aussi s’associer entre eux pour former des complexes oligomériques pouvant comprendre différents sous-types (RAMP1/RAMP2 et RAMP1/RAMP3). Cette observation de la présence d’homo-oligomères de CLR et de RAMP1, nous a amené à nous questionner sur la stœchiométrie d’interaction du complexe CLR/RAMP1. Dans une deuxième étude ayant pour but d’établir la composition moléculaire du récepteur CGRP1 in vivo, nous avons développé une nouvelle approche permettant l’étude de l’interaction entre trois protéines dans un contexte de cellules vivantes. Cette technique baptisée BRET/BiFC, est basée sur le transfert d’énergie de résonance de bioluminescence entre un donneur luminescent, la Renilla luciférase, et un accepteur fluorescent, la protéine fluorescente jaune (YFP), reconstituée suite au ré-assemblage de ces deux fragments. En utilisant cette approche, nous avons pu déterminer que le récepteur CGRP1 est constitué d’un homo-oligomère de CLR interagissant avec un monomère de RAMP1. En démontrant un assemblage oligomérique asymétrique pour le récepteur CGRP1 à partir d’une nouvelle approche biophysique, nous croyons que les travaux présentés dans cette thèse ont contribué à élargir nos connaissances sur le fonctionnement de la grande famille des RCPGs, et seront utile à la poursuite des recherches sur les complexes protéiques impliqués dans la signalisation. / G protein coupled receptors (GPCRs) constitute the largest family of membrane receptors involved in signal transduction. Traditionally, signal transduction by GPCRs involves the activation of a hetero-trimeric G protein which will then modulate the activity of several intracellular effectors. We can now appreciate the fact that in addition to their interaction with G proteins, GPCRs also associate with several other proteins, in order to allow proper signal transduction. In particular, the discovery of a family of proteins called receptor activity-modifying proteins (RAMPs) has challenged the traditional views of signal transduction by some GPCRs. In the case of the calcitonin-like receptor (CLR), the association with RAMPs allows the proper cell surface targeting of the receptor in addition to modulate it’s pharmacological properties. Co-expression of CLR with RAMP1 leads to a calcitonin gene-related peptide (CGRP) receptor, whereas CLR association with RAMP2 or RAMP3 promotes the formation of an adrenomedullin receptor. In addition to their interaction with transmembrane accessory proteins such as RAMPs, GPCRs can also interact with other receptors to form receptors oligomers. In this thesis, we were interested in the interactions between GPCRs and RAMPs, and particularly, in the link between these GPCR/RAMP interactions and the assembly of receptor oligomers, using CGRP1 receptor as a model. We first confirmed the interaction between CLR and RAMP1 in living cells. We showed that this CLR/RAMP1 complex activates G proteins and recruits the signalling protein -arrestin upon CGRP stimulation. Next, we demonstrated that even if the CLR requires hetero-oligomeric assembly with RAMPs in order to be active, this receptor can still interact with other GPCRs. In addition to CLR homo-oligomers, we observed that RAMPs can also self-associate to form oligomeric complexes which can involve different subtypes (RAMP1/RAMP2 and RAMP1/RAMP3). This observation of the presence of CLR and RAMP1 homo-oligomers raised the question of the stoiechiometry of interaction of the CLR/RAMP1 complex. In order to establish the molecular composition of the CGRP1 receptor in vivo, we developed a novel approach allowing the detection of the interaction between three proteins in living cells. This method called BRET/BiFC is based on the bioluminescence resonance energy transfer between a luminescent energy donor, Renilla luciferase, and a fluorescent energy acceptor, the yellow fluorescent protein (YFP), reconstituted after the re-association of its two fragments. Using this approach, we showed that the CGRP1 receptor consist of a homo-oligomer of CLR interacting with a monomer of RAMP1. By demonstrating the asymmetrical organization of the CGRP1 receptor complex using a novel biophysical approach, we believe that the results presented herein have contributed to increase our knowledge of the mechanisms of function of the large family of GPCRs and will be useful for the pursuit of research on protein complexes involved in signalling pathways.
66

Régulation transcriptionnelle des isoformes de la protéine suppresseur de tumeur p53 tronquée dans leur région amino-terminale : impact des polymorphismes du gène TP53 / Transcriptional regulation of N-truncated isoforms of the p53 tumor suppressor : impact of the TP53 polymorphisms

Marcel, Virginie 30 June 2009 (has links)
Le gène suppresseur de tumeurs TP53 exprime plusieurs isoformes, dont Δ40p53 (perte du domaine de transactivation) et Δ133p53 (perte du domaine de transactivation et d’une partie du domaine de liaison à l’ADN). Ces isoformes inhibent l’activité suppressive de p53 et seraient sur-exprimées dans les cancers (sein et mélanome). Dans les cancers faiblement associés à une mutation TP53, ces isoformes seraient de bons candidats pour inactiver p53. Il convient de comprendre les mécanismes transcriptionnels qui régulent leurs expressions. Δ133p53 est produite par un promoteur alternatif P3 localisé dans TP53. Nous avons montré que Δ133p53 est un gène cible de p53, qui transactive le promoteur P3 par fixation sur un élément de réponse présent dans l’exon 4. L’expression de Δ133p53 est corrélée à celle d’autres gènes cibles de p53 en réponse à un stress génotoxique. De plus, elle réprime la suppression de la prolifération induite par p53 en inhibant ses capacités de liaison à l’ADN. Δ40p53 est produite par épissage alternatif, dont la rétention de l’intron 2 favorise sa traduction et empêche celle de p53. Nous avons montré que des structures de type G-quadruplexes présentes dans l’intron 3 régulent l’exclusion de l’intron 2. Ces structures comprennent le polymorphisme TP53PIN3 (duplication de 16pb), qui change leur localisation et affecte l’expression des ARNm codant p53 et Δ40p53. De plus, nous avons montré que ce polymorphisme est associé à une accélération de la cancérogenèse dans le syndrome Li-Fraumeni, caractérisé par la présence d’une mutation germinale TP53 (effet modificateur: 19 ans de différence à l’âge moyen du premier diagnostique entre les deux variants). L’expression des isoformes de p53 dépend de mécanismes transcriptionnels différents, indiquant des rôles différents dans la modulation des fonctions suppressives de p53. En plus d’inactiver p53 dans les cancers, ces isoformes pourraient être à l’origine des effets modificateurs des polymorphismes de TP53 sur les mutants p53. / The TP53 tumour suppressor gene expresses several isoforms, of which Δ40p53 (lack of transactivation domain) and Δ133p53 (lack of both transactivation and part of DNA-binding domains). These isoforms inhibit p53 suppressive activity and have been shown to be over-expressed in cancers (breat and melanoma). In cancers associated with low TP53 mutation rate, these isoforms could be great candidates to inactivate p53. It seems important to understand the transcriptional mechanisms that regulate their expression. Δ133p53 is produced by an alternative P3 promoter within TP53. We showed that Δ133p53 is a p53 target gene. p53 transactivates the P3 promoter and interact with a response element within exon 4. Δ133p53 expression is correlated to other p53 target genes in response to genotoxic stress. In addition, Δ133p53 inhibits p53-dependent suppression of proliferation by inhibiting p53 DNA-binding activity. Δ40p53 is produced by alternative splicing: retention of intron 2 favours its translation while it avoid the one of p53. We showed that G-quadruplex structures are formed in intron 3 and regulate retention of intron 2. The TP53PIN3 polymorphism (16 bp duplication) is embedded within these structures and affects their locations leading to variation of mRNA expression of p53 and Δ40p53. In addition, we showed that this polymorphism is associated with acceleration of carcinogenesis in Li-Fraumeni syndrome, characterized by germline TP53 mutation (genetic modifier effect: difference of 19 years in mean age at first diagnosis of cancer between the two variants). The expression of p53 isoforms depends on different transcriptional mechanisms, suggesting different roles in the modulation of p53 suppressive functions. In addition to inactivate p53 in cancers, these isoforms could be the mediators of modifier effects observed for TP53 polymorphisms on mutant p53.
67

Dispositivos adaptativos cooperantes: formulação e aplicação. / Cooperative adaptive devices : design and implementation.

Santos, José Maria Novaes dos 26 November 2014 (has links)
Com a crescente complexidade das aplicações e sistemas computacionais, atualmente tem se tornado importante o uso de formalismos de várias naturezas na representação e modelagem de problemas complexos, como os sistemas reativos e concorrentes. Este trabalho apresenta uma contribuição na Tecnologia Adaptativa e uma nova técnica no desenvolvimento de uma aplicação para execução de alguns tipos de jogos, (General Game Playing), cuja característica está associada à capacidade de o sistema tomar conhecimento das regras do jogo apenas em tempo de execução. Com esse trabalho, amplia-se a classe de problemas que podem ser estudados e analisados sob a perspectiva da Tecnologia Adaptativa, através dos Dispositivos Adaptativos Cooperantes. A aplicação desenvolvida como exemplo neste trabalho introduz uma nova ótica no desenvolvimento de aplicações para jogos gerais (GGP) e abre novos horizontes para a aplicação da Tecnologia Adaptativa, como a utilização das regras para extração de informação e inferência. / The complexity of computer applications has grown so much that several formalisms of different kinds became important nowadays. Many systems (e.g. reactive and concurrent ones) employ such formalisms to represent and model actual complex problems. This work contributes to the field of Adaptive Technology, and proposes a new approach for developing general game playing system, whose feature is the capability to play a game by acknowledging the game rules only at run time. This work expands the set of problems that can be studied and analyzed under the Adaptive Technology perspective, by means of cooperating adaptive devices. The developed application used a new approach for general game playing development bringing and widens the application field of Adaptive Technology with subjects related to information extraction and inference based in the devices rules.
68

Dispositivos adaptativos cooperantes: formulação e aplicação. / Cooperative adaptive devices : design and implementation.

José Maria Novaes dos Santos 26 November 2014 (has links)
Com a crescente complexidade das aplicações e sistemas computacionais, atualmente tem se tornado importante o uso de formalismos de várias naturezas na representação e modelagem de problemas complexos, como os sistemas reativos e concorrentes. Este trabalho apresenta uma contribuição na Tecnologia Adaptativa e uma nova técnica no desenvolvimento de uma aplicação para execução de alguns tipos de jogos, (General Game Playing), cuja característica está associada à capacidade de o sistema tomar conhecimento das regras do jogo apenas em tempo de execução. Com esse trabalho, amplia-se a classe de problemas que podem ser estudados e analisados sob a perspectiva da Tecnologia Adaptativa, através dos Dispositivos Adaptativos Cooperantes. A aplicação desenvolvida como exemplo neste trabalho introduz uma nova ótica no desenvolvimento de aplicações para jogos gerais (GGP) e abre novos horizontes para a aplicação da Tecnologia Adaptativa, como a utilização das regras para extração de informação e inferência. / The complexity of computer applications has grown so much that several formalisms of different kinds became important nowadays. Many systems (e.g. reactive and concurrent ones) employ such formalisms to represent and model actual complex problems. This work contributes to the field of Adaptive Technology, and proposes a new approach for developing general game playing system, whose feature is the capability to play a game by acknowledging the game rules only at run time. This work expands the set of problems that can be studied and analyzed under the Adaptive Technology perspective, by means of cooperating adaptive devices. The developed application used a new approach for general game playing development bringing and widens the application field of Adaptive Technology with subjects related to information extraction and inference based in the devices rules.
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Assemblage oligomérique des récepteurs couplés aux protéines G avec les RAMPs

Héroux, Madeleine 03 1900 (has links)
Les récepteurs couplés aux protéines G (RCPGs) constituent la plus grande classe de récepteurs membranaires impliqués dans la transmission des signaux extracellulaires. Traditionnellement, la transmission de la signalisation par les RCPGs implique l’activation d’une protéine G hétéro-trimérique qui pourra à son tour moduler l’activité de divers effecteurs intracellulaires. Ce schéma classique de signalisation s’est complexifié au fils des années et l’on sait maintenant qu’en plus d’interagir avec les protéines G, les RCPGs s’associent avec une panoplie d’autres protéines afin de transmettre adéquatement les signaux extracellulaires. En particulier, la découverte d’une famille de protéines transmembranaires modulant la fonction des RCPGs, baptisées protéines modifiant l’activité des récepteurs (« receptor activity-modifying proteins » ; RAMPs), a changé la façon de concevoir la signalisation par certains RCPGs. Dans le cas du récepteur similaire au récepteur de la calcitonine (« calcitonin-like receptor » ; CLR), l’association avec les RAMPs permet l’acheminement à la surface cellulaire du récepteur tout en modulant ses propriétés pharmacologiques. Lorsqu’il est associé avec RAMP1, le CLR fonctionne comme un récepteur du peptide relié au gène de la calcitonine (« calcitonin gene-related peptide » ; CGRP), alors qu’il devient un récepteur de l’adrénomedulline lorsqu’il interagit avec RAMP2 ou RAMP3. D’autre part, en plus d’interagir avec des protéines accessoires transmembranaires telles les RAMPs, les RCPGs peuvent aussi s’associer entre eux pour former des oligomères de récepteurs. Dans cette thèse, nous nous sommes penchés sur les interactions entre les RCPGs et les RAMPs, et plus particulièrement sur l’interrelation entre ce type d’association RCPG/RAMP et l’assemblage en oligomères de récepteurs, en utilisant le récepteur du CGRP comme modèle d’étude. Une première étude nous a tout d’abord permis de confirmer l’interaction entre le récepteur CLR et RAMP1, dans un contexte de cellules vivantes. Nous avons démontré que ce complexe CLR/RAMP1 active la protéine G et recrute la protéine de signalisation -arrestine suite à une stimulation par le CGRP. Ensuite, nous avons déterminé que même s’il doit obligatoirement former un hétéro-oligomère avec les RAMPs pour être actif, le CLR conserve malgré tout sa capacité à interagir avec d’autres RCPGs. En plus d’observer la présence d’homo-oligomère de CLR, nous avons constaté que tout comme les RCPGs, les RAMPs peuvent eux-aussi s’associer entre eux pour former des complexes oligomériques pouvant comprendre différents sous-types (RAMP1/RAMP2 et RAMP1/RAMP3). Cette observation de la présence d’homo-oligomères de CLR et de RAMP1, nous a amené à nous questionner sur la stœchiométrie d’interaction du complexe CLR/RAMP1. Dans une deuxième étude ayant pour but d’établir la composition moléculaire du récepteur CGRP1 in vivo, nous avons développé une nouvelle approche permettant l’étude de l’interaction entre trois protéines dans un contexte de cellules vivantes. Cette technique baptisée BRET/BiFC, est basée sur le transfert d’énergie de résonance de bioluminescence entre un donneur luminescent, la Renilla luciférase, et un accepteur fluorescent, la protéine fluorescente jaune (YFP), reconstituée suite au ré-assemblage de ces deux fragments. En utilisant cette approche, nous avons pu déterminer que le récepteur CGRP1 est constitué d’un homo-oligomère de CLR interagissant avec un monomère de RAMP1. En démontrant un assemblage oligomérique asymétrique pour le récepteur CGRP1 à partir d’une nouvelle approche biophysique, nous croyons que les travaux présentés dans cette thèse ont contribué à élargir nos connaissances sur le fonctionnement de la grande famille des RCPGs, et seront utile à la poursuite des recherches sur les complexes protéiques impliqués dans la signalisation. / G protein coupled receptors (GPCRs) constitute the largest family of membrane receptors involved in signal transduction. Traditionally, signal transduction by GPCRs involves the activation of a hetero-trimeric G protein which will then modulate the activity of several intracellular effectors. We can now appreciate the fact that in addition to their interaction with G proteins, GPCRs also associate with several other proteins, in order to allow proper signal transduction. In particular, the discovery of a family of proteins called receptor activity-modifying proteins (RAMPs) has challenged the traditional views of signal transduction by some GPCRs. In the case of the calcitonin-like receptor (CLR), the association with RAMPs allows the proper cell surface targeting of the receptor in addition to modulate it’s pharmacological properties. Co-expression of CLR with RAMP1 leads to a calcitonin gene-related peptide (CGRP) receptor, whereas CLR association with RAMP2 or RAMP3 promotes the formation of an adrenomedullin receptor. In addition to their interaction with transmembrane accessory proteins such as RAMPs, GPCRs can also interact with other receptors to form receptors oligomers. In this thesis, we were interested in the interactions between GPCRs and RAMPs, and particularly, in the link between these GPCR/RAMP interactions and the assembly of receptor oligomers, using CGRP1 receptor as a model. We first confirmed the interaction between CLR and RAMP1 in living cells. We showed that this CLR/RAMP1 complex activates G proteins and recruits the signalling protein -arrestin upon CGRP stimulation. Next, we demonstrated that even if the CLR requires hetero-oligomeric assembly with RAMPs in order to be active, this receptor can still interact with other GPCRs. In addition to CLR homo-oligomers, we observed that RAMPs can also self-associate to form oligomeric complexes which can involve different subtypes (RAMP1/RAMP2 and RAMP1/RAMP3). This observation of the presence of CLR and RAMP1 homo-oligomers raised the question of the stoiechiometry of interaction of the CLR/RAMP1 complex. In order to establish the molecular composition of the CGRP1 receptor in vivo, we developed a novel approach allowing the detection of the interaction between three proteins in living cells. This method called BRET/BiFC is based on the bioluminescence resonance energy transfer between a luminescent energy donor, Renilla luciferase, and a fluorescent energy acceptor, the yellow fluorescent protein (YFP), reconstituted after the re-association of its two fragments. Using this approach, we showed that the CGRP1 receptor consist of a homo-oligomer of CLR interacting with a monomer of RAMP1. By demonstrating the asymmetrical organization of the CGRP1 receptor complex using a novel biophysical approach, we believe that the results presented herein have contributed to increase our knowledge of the mechanisms of function of the large family of GPCRs and will be useful for the pursuit of research on protein complexes involved in signalling pathways.
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Differential effects of selective versus unselective sphingosine 1-phosphate receptor modulators on T- and B-cell response to SARS-CoV-2 vaccination

Proschmann, Undine, Mueller-Enz, Magdalena, Woopen, Christina, Katoul Al Rahbani, Georges, Haase, Rocco, Dillenseger, Anja, Dunsche, Marie, Atta, Yassin, Ziemssen, Tjalf, Akgün, Katja 05 August 2024 (has links)
Background: Sphingosine 1-phosphat receptor modulators (S1PRMs) have been linked to attenuated immune response to SARS-CoV-2 vaccines. Objective: To characterize differences in the immune response to SARS-CoV-2 vaccines in patients on selective versus unselective S1PRMs. Methods: Monocentric, longitudinal study on people with multiple sclerosis (pwMS) on fingolimod (FTY), siponimod (SIP), ozanimod (OZA), or without disease-modifying therapy (DMT) following primary and booster SARS-CoV-2 vaccination. Anti-SARS-CoV-2 antibodies and T-cell response was measured with electro-chemiluminescent immunoassay and interferon-γ release assay. Results: Primary vaccination induced a significant antibody response in pwMS without DMT while S1PRM patients exhibited reduced antibody titers. The lowest antibodies were found in patients on FTY, whereas patients on OZA and SIP presented significantly higher levels. Booster vaccinations induced increased antibody levels in untreated patients and comparable titers in patients on OZA and SIP, but no increase in FTY-treated patients. While untreated pwMS developed a T-cell response, patients on S1PRMs presented a diminished/absent response. Patients undergoing SARS-CoV-2 vaccination before onset of S1PRMs presented a preserved, although attenuated humoral response, while T-cellular response was blunted. Conclusion: Our data confirm differential effects of selective versus unselective S1PRMs on T- and B-cell response to SARS-CoV-2 vaccination and suggest association with S1PRM selectivity rather than lymphocyte redistribution.

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