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Développement d'un promoteur efficace et muscle spécifique pour la thérapie génique de la dystrophie musculaire de DuchenneBlain, Marilyne January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
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Quantificação da força muscular e habilidades motoras de pacientes com Distrofia Muscular de Duchenne, em corticoterapia por período de 1 a 7 anos / Quantification of muscle strength and motor abilities in patients with Duchenne muscular dystrophy on steroid therapy for periods of 1 to 7 yearsParreira, Samara Lamounier Santana 29 April 2010 (has links)
Os objetivos deste trabalho foram: comparar a força muscular (FM) e as habilidades motoras de pacientes com Distrofia Muscular de Duchenne (DMD) em corticoterapia com a evolução natural da doença (Scott, 1982) e identificar a idade ideal de início da corticoterapia. Noventa pacientes com DMD em seguimento ambulatorial no Hospital das Clínicas da Faculdade de Medicina da USP, submetidos à corticoterapia (deflazacort ou prednisolona) por um período variável de um a sete anos, foram avaliados quanto à FM através da escala MRC e quanto às habilidades motoras através da escala Hammersmith motor ability score. Foram incluídos no estudo todos os pacientes com idade entre cinco e 12 anos, que compreendiam comandos verbais e que não haviam sido submetidos a cirurgias ortopédicas corretivas ou interrompido em algum momento a corticoterapia. A relação entre FM e habilidades motoras, a comparação dos dados com aqueles do estudo de Scott et al. e a análise da influência do tempo de tratamento, da idade de início e da idade na avaliação, sobre os valores obtidos nos testes foram submetidas a tratamento estatístico. Concluiu-se que: a progressão da perda da FM e das habilidades motoras em relação à idade foi mais lenta do que a da evolução natural em todas as faixas etárias avaliadas; quanto maior a idade maior a diferença entre os dois estudos; a perda da FM foi mais intensa do que a perda da funcionalidade; a metodologia utilizada não permitiu estabelecer com clareza a influência da idade de início do tratamento sobre os parâmetros avaliados, porém demonstrou a influência positiva do tempo de tratamento sobre a FM e habilidades motoras. / The aims of this study were: to compare muscle strength (MS) and motor abilities of Duchenne Muscular Dystrophy (DMD) patients in use of steroids, with the natural evolution of the disease (Scott, 1982) and to identify the ideal age for starting on steroid therapy. Ninety patients with DMD followed as outpatients at the Clinics Hospital of the University of São Paulo School of Medicine and submitted to steroid therapy (deflazacort or prednisolone) for a period of one to seven years were assessed for MS using the MRC scale, and for motor abilities with the motor ability score from the Hammersmith scale. All patients aged between five and 12 years who understood verbal commands and who had not been submitted to corrective orthopedic surgery and had no interruption in steroid therapy, were included in the study. Statistical analysis was carried out to assess the relationship between MS and motor abilities and to compare our data against results of Scott\'s study. The influence of length of treatment, age at disease onset and first assessment, on values obtained in the tests was investigated. We concluded that: the progression in loss of MS and of motor abilities with age was slower than the natural evolution across all age groups studied; the higher the age the greater the difference between the two studies; loss of MS was more intense than loss of functionality; the methodology used was unable to clearly ascertain the influence of age at treatment on the parameters assessed, but a positive influence of length of treatment on both MS and motor abilities was identified.
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Responsividade do domínio subir e descer escada da escala de avaliação funcional para pessoas com distrofia muscular de Duchenne, no período de um ano / Responsiveness of the domain go up and down stair of the functional evaluation scale for Duchenne muscular dystrophy, in one year follow upAlbuquerque, Priscila Santos 19 April 2016 (has links)
Objetivo: Determinar a responsividade do domínio subir e descer escada da escala de avaliação funcional em distrofia muscular de Duchenne (DMD), no período de um ano. Método: Participaram do estudo 26 pacientes com DMD. A análise utilizou o Tamanho do Efeito (ES) e a Média Padronizada de Resposta (SRM). Resultados: Atividade de subir escada: o ES mostrou responsividade baixa nos intervalos de avaliação de 3 meses (0,26; 0,35; 0,13; 0,17), baixa a moderada em 6 meses (0,58, 0,48; 0,33), moderada em 9 meses (0,70; 0,68) e alta em 1 ano (0,88). A análise com SRM mostrou responsividade baixa nos intervalos de avaliação de 3 meses (0,29; 0,38; 0,18 e 0,19), baixa a moderada em intervalos de 6 meses (0,59 e 0,51, 0,36), moderada em 9 meses (0,74 e 0,70) e alta em 1 ano (0,89). Atividade de descer escada: O ES apresentou responsividade baixa nos intervalos de avaliação de 3 meses (0,16; 0,25; 0,09; 0,08) e 6 meses (0,48; 0,35; 0,18), baixa a moderada em 9 meses (0,59, 0,44) e moderada em 1 ano (0,71). Análise com SRM mostrou responsividade baixa nos intervalos de 3 meses (0,25; 0,35; 0,12 e 0,09) e 6 meses (0,47; 0,38 e 0,21), moderada a baixa em 9 meses (0,62, 0,49) e moderada em 1 ano (0,74). Conclusão: A avaliação da atividade de subir escada, por meio da FES-DMD-D3, deve ser realizada em intervalos a partir de 9 meses, pois a responsividade é de moderada a alta. A avaliação do descer escadas deve ser realizada anualmente, pois houve responsividade moderada somente a partir de 12 meses / Objective: To determine the responsiveness of the domain up and down stair Functional Evaluation Scale for Duchenne Muscular Dystrophy (DMD) in one year follow-up. Method: The study included 26 patients with DMD. The analysis used the Effect Size (ES) and Standardized Response Mean (SRM) tests. Results: Climbing stairs activity: the ES test showed low responsiveness in the 3-month evaluation intervals (0.26; 0.35; 0.13; 0.17), low to moderate at 6 months (0.58, 0 48; 0.33), moderate in 9 months (0.70, 0.68) and high in one year (0.88). The SRM analysis showed low response in the 3 month evaluation interval (0.29, 0.38, 0.18 and 0.19), moderate to low every 6 months (0.59 and 51, 0, 36), moderate in 9 months (0.74 and 0.70) and high in one year (0.89). Down stairs activity: The ES test showed low responsiveness in the 3 month evaluation intervals (0.16; 0.25; 0.09; 0.08) and 6 months (0.48, 0.35, 0, 18), low to moderate at 9 months (0.59, 0.44) and moderate in 1 year (0.71). SRM Analysis showed low response at intervals of 3 months (0.25; 0.35; 0.12 and 0.09) and 6 months (0.47, 0.38 and 0.21), low to moderate 9 months (0.62, 0.49) and moderate in 1 year (0.74). Conclusion: The assessment of stair climbing up should be performed in 9 months or longer intervals, when responsiveness is moderate to high. Going down stairs assessment should be performed annually, because moderate responsiveness was observed in 1 year interval
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Etude de thérapies génique et pharmacologique visant à restaurer les capacités cognitives d’un modèle murin de la Dystrophie musculaire de Duchenne / Gene and pharmacological therapies to restore cognitive abilities of a mouse model of Duchenne muscular DystrophyPerronnet, Caroline 21 January 2011 (has links)
L’objectif était d’évaluer l’efficacité de thérapies développées pour traiter la dystrophie musculaire de Duchenne (DMD, due à des mutations du gène de la dystrophine) dans la restauration de déficits cognitifs associés à ce syndrome. Deux pistes thérapeutiques visant à compenser les altérations cérébrales liées à la perte de dystrophine ont été explorées chez les souris mdx, modèle de DMD. Une approche pharmacologique basée sur la surexpression de l’utrophine, homologue de la dystrophine, n’améliore pas les déficits comportementaux des souris mdx. Par contre, une intervention génique basée sur l’épissage de l’exon muté conduit à la restauration d’une dystrophine endogène et une récupération d’altérations cérébrales comme l’agrégation des récepteurs GABAA et la plasticité synaptique hippocampique. Ceci suggère un rôle de la dystrophine dans la plasticité du cerveau adulte et l’applicabilité de cette approche de thérapie génique au traitement des altérations cognitives de la DMD. / Therapies have been developed to treat Duchenne muscular dystrophy (DMD, due to mutation in the dystrophin gene), but their ability to restore the cognitive deficits associated with this syndrome has not been yet studied. We explored two therapeutic approaches to compensate for the brain alterations resulting from the loss of dystrophin in the mdx mouse, a model of DMD. A pharmacological approach based on the overexpression of utrophin, a dystrophin homologue, does not alleviate the behavioural deficits in these mice. In contrast, a genetic intervention based on the splicing of the mutated exon leads to the restoration of endogenous dystrophin and a recovery of brain alterations such as the clustering of GABAA receptors and hippocampal synaptic plasticity in mdx mice. These results suggest a role for dystrophin in adult brain plasticity and indicate that this gene therapy approach is applicable to the treatment of cognitive impairments in DMD.
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Avaliação da efetividade e segurança do treinamento da manobra de empilhamento de ar nas distrofinopatias / Evaluation of the effectiveness and safety profile of air stacking in dystrophinopathiesFernandes, Adriane Sayuri Nakashima 27 January 2015 (has links)
INTRODUÇÃO: As distrofias musculares (DM) constituem um grupo de doenças genéticas caracterizadas por fraqueza muscular progressiva decorrente da degeneração irreversível do tecido muscular esquelético. O comprometimento da função respiratória é um sinal precoce da progressão da doença. A fraqueza progressiva dos músculos respiratórios torna o paciente com distrofia muscular incapaz de realizar inspirações profundas de forma independente para promover uma tosse eficaz. Portanto, torna-se necessário fornecer insuflações regulares com volumes que o paciente aprende a empilhar com o fechamento da glote, até que atinja a capacidade de insuflação máxima (CIM). A insuflação pulmonar minimiza complicações, tais como atelectasias e pneumonias, e permite níveis apropriados de ventilação e troca gasosa adequada nas eventuais complicações pulmonares, as quais impõem carga sobre os músculos respiratórios. Este mesmo processo pode representar uma alternativa para otimizar a função respiratória (FP) por meio do aumento do pico de fluxo de tosse (PFT) e manter a complacência pulmonar. Nos pacientes com distrofia muscular causada por mutações do gene da distrofina, a abordagem respiratória aumentou a sobrevida, sendo hoje as complicações cardiovasculares a maior causa de mortalidade. Entretanto, a manobra de empilhamento de ar ainda não foi adequadamente avaliada nestes pacientes. OBJETIVOS: Investigar a efetividade e a segurança desta manobra durante um período de um ano de treinamento em pacientes com Distrofia Muscular de Duchenne (DMD). MÉTODOS: Em 60 pacientes com DMD, cardiopatas e não cardiopatas, foram avaliados a FP, o PFT e a resposta cardíaca como frequência cardíaca (FC), pressão arterial (PA) e sintomas associados, antes, durante a sustentação e após a manobra de empilhamento de ar, em uma primeira avaliação, e depois de um ano de orientação e treinamento. Após o treinamento, foi avaliada, também, a variabilidade da frequência cardíaca (VFC). RESULTADOS: Houve um ganho da Capacidade vital forçada (CVF) e do PFT após um ano de treinamento (p < 0,05), Houve uma correlação linear entre o ganho de CIM e o PFT. Houve diferença na FC e na PA sistólica (PAS) durante a sustentação da manobra em comparação aos outros tempos, sendo que, no grupo de pacientes cardiopatas, a resposta cardíaca foi mais evidente, associada, em alguns pacientes, a sintomas relacionados a baixo débito cardíaco, tais como náuseas e tonturas (p < 0,05). Houve diferença significativa nos valores da VFC durante a manobra. (p < 0,05). CONCLUSÃO: O treinamento da manobra de empilhamento, durante um ano, proporcionou ganho e manutenção da função pulmonar, além de alterações cardíacas significativas associadas a sintomas apenas durante a sustentação da manobra, principalmente nos pacientes cardiopatas / INTRODUCTION: Muscular dystrophy (MD) is a genetic disease characterized by progressive muscle weakness resulting from irreversible degeneration of skeletal muscle tissue. An early sign of disease progression is the impairment of respiratory function. The progressive respiratory muscle weakness makes the patient with muscular dystrophy be unable to perform independent deep breaths in order to promote an effective cough. Therefore, it becomes necessary to provide regular inflations with volumes until it reaches the maximum insufflation capacity (MIC). Pulmonary insufflation minimizes complications such as pneumonia and atelectasis, and allows proper ventilation levels and adequate gas exchange in pulmonary complications. This same process can be an alternative to optimize pulmonary function (PF) by increasing peak cough flow (PCF) and maintain pulmonary compliance. In patients with muscular dystrophy respiratory approach increased their survival. Nowadays, cardiovascular complications is main a leading cause of mortality. However the air stacking has not been adequately evaluated in these patients. OBJECTIVES: To investigate the effectiveness of air stacking exercise and its safety profile in DM. METHODS: We evaluated 60 patients with DMD and with and without heart disease, the PF and PCF; cardiac response as heart rate (HR), blood pressure (BP), and associated symptoms before, during sustained time and after air stacking in the first review, and a year after being advised and trained. After twelve months was also measured the heart rate variability (HRV). RESULTS: There was a statistically difference in forced vital capacity (FVC) and PCF after a year of air stacking (p < 0.05). There was a linear correlation between MIC and PCF (R=0.8). Differences in HR and blood arterial systolic pressure (BPS) at sustainet time of air stacking compared to other times, moreover, in the heart disease group cardiovascular response was more evident, associated in some patients with low cardiac output related symptoms such as nausea and dizziness (p < 0.05). There was a significant difference in HRV values during air stacking (p < 0.05). CONCLUSION: The air stacking for twelvemonths provided gain and maintenance of pulmonary function, beyond a significant cardiac response abnormalities only during sustained time specially in heart disease patients associated with symptoms
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Quantificação da força muscular e habilidades motoras de pacientes com Distrofia Muscular de Duchenne, em corticoterapia por período de 1 a 7 anos / Quantification of muscle strength and motor abilities in patients with Duchenne muscular dystrophy on steroid therapy for periods of 1 to 7 yearsSamara Lamounier Santana Parreira 29 April 2010 (has links)
Os objetivos deste trabalho foram: comparar a força muscular (FM) e as habilidades motoras de pacientes com Distrofia Muscular de Duchenne (DMD) em corticoterapia com a evolução natural da doença (Scott, 1982) e identificar a idade ideal de início da corticoterapia. Noventa pacientes com DMD em seguimento ambulatorial no Hospital das Clínicas da Faculdade de Medicina da USP, submetidos à corticoterapia (deflazacort ou prednisolona) por um período variável de um a sete anos, foram avaliados quanto à FM através da escala MRC e quanto às habilidades motoras através da escala Hammersmith motor ability score. Foram incluídos no estudo todos os pacientes com idade entre cinco e 12 anos, que compreendiam comandos verbais e que não haviam sido submetidos a cirurgias ortopédicas corretivas ou interrompido em algum momento a corticoterapia. A relação entre FM e habilidades motoras, a comparação dos dados com aqueles do estudo de Scott et al. e a análise da influência do tempo de tratamento, da idade de início e da idade na avaliação, sobre os valores obtidos nos testes foram submetidas a tratamento estatístico. Concluiu-se que: a progressão da perda da FM e das habilidades motoras em relação à idade foi mais lenta do que a da evolução natural em todas as faixas etárias avaliadas; quanto maior a idade maior a diferença entre os dois estudos; a perda da FM foi mais intensa do que a perda da funcionalidade; a metodologia utilizada não permitiu estabelecer com clareza a influência da idade de início do tratamento sobre os parâmetros avaliados, porém demonstrou a influência positiva do tempo de tratamento sobre a FM e habilidades motoras. / The aims of this study were: to compare muscle strength (MS) and motor abilities of Duchenne Muscular Dystrophy (DMD) patients in use of steroids, with the natural evolution of the disease (Scott, 1982) and to identify the ideal age for starting on steroid therapy. Ninety patients with DMD followed as outpatients at the Clinics Hospital of the University of São Paulo School of Medicine and submitted to steroid therapy (deflazacort or prednisolone) for a period of one to seven years were assessed for MS using the MRC scale, and for motor abilities with the motor ability score from the Hammersmith scale. All patients aged between five and 12 years who understood verbal commands and who had not been submitted to corrective orthopedic surgery and had no interruption in steroid therapy, were included in the study. Statistical analysis was carried out to assess the relationship between MS and motor abilities and to compare our data against results of Scott\'s study. The influence of length of treatment, age at disease onset and first assessment, on values obtained in the tests was investigated. We concluded that: the progression in loss of MS and of motor abilities with age was slower than the natural evolution across all age groups studied; the higher the age the greater the difference between the two studies; loss of MS was more intense than loss of functionality; the methodology used was unable to clearly ascertain the influence of age at treatment on the parameters assessed, but a positive influence of length of treatment on both MS and motor abilities was identified.
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Analyser le gène PKC-2 chez Caernorhabditis elegans et crible les mutants contre sérotonine chez le C. elegans souche pkc-2 (ok328) / Analysis of pkc-2 gene of Caenorhabaditis elegans and screen for serotonin resistant mutant in pkc-2(ok328) backgroundQian, Yu 28 September 2009 (has links)
La myopathie de Duchenne est une maladie génétique qui se caractérise principalement par une dégénérescence progressive des muscles squelettiques dont la cause est l’absence de dystrophine fonctionnelle dans les muscles. A ce jour, il n’existe toujours pas de traitement efficace contre ces maladies. Comme le plus grand gène connu chez l’Homme, la dystrophine code pour une protéine de 427kDa. La protéine connecte l’actine avec le DAPC (Dystrophin Associated Protein Complex) dans les muscles striés. Pour l’instant, il y a 3 hypothèses concernant le mécanisme du DMD. L’absence de la dystrophine peut supprimer le lien physique entre les protéines structurales de la membrane basale (laminines) et les protéines structurales du cytosquelette (filaments intermédiaires et actine), ou la distribution et la fonction des canaux ioniques, ou des voies de signalisation nécessaires à la survie du muscle. Caenorhabditis elegans ne possède qu’un homologue du gène de la dystrophine humaine, le gène dys-1. La protéine DYS-1 présente 37% d’homologie avec la dystrophine humaine. Le double mutant dys-1(cx18) ; hlh-1(cc561) présente une forte dégénérescence musculaire. Comme le sarcomère de C. elegans ressemble au sarcomère de mammifère, C. elegans est modèle pertinent d’étude la maladie. En vue de comprendre la raison du DMD chez les mammifères et chez les vers, le groupe L. SEGALAT a effectué des cribles pour identifier les molécules et les gènes qui peuvent supprimer la dégénérescence musculaire. On a trouvé un gène pkc-2 qui est capable de supprimer la dégénérescence musculaire chez C. elegans. La protéine PKC-2 est l’orthologue de la Protein Kinase C Alpha (PKC) humaine et appartient à la famille du serine/threonine protéine kinase. Afin d’étudier la fonction du gène pkc-2, on a analysé l’expression du gène avec les construits différents in vivo et a utilisé la technique de double-hybride dans la levure. De plus, le crible par EMS (éthane méthyle sulfonâtes) a identifié une molécule sérotonine (5-HT) qui est un neuromédiateur, et supprime partiellement la dégénérescence musculaire des doubles mutants dys-1; hlh-1. La sérotonine a aussi un effet fort sur le mutant pkc-2(ok328), puisqu’elle provoque un phénotype blister. Ça nous permet de rechercher le lien entre la signalisation sérotoninergique et pkc-2. Le crible génétique peut contribuer à la connaissance du rôle pkc-2. […]. Elle sert aussi de plate-forme de voie de signalisation intracellulaire. L’identification de Y59A8A.3 propose la possibilité que pkc-2 modifie la filamin A par l’intermédiaire de la filamin A interacting protéine 1. Le crible génétique par EMS pour rechercher des suppresseurs de l’effet blister de la sérotonine sur les mutants pkc-2(ok328) a donné 8 candidats sur 5000 F1s : cx253, cx254, cx259, cx263, cx267, cx268, cx270, cx276. Les mutations ont été localisées sur les chromosomes par SNP mapping avec une souche de C. elegans très polymorphe, mais le temps a manqué pour leur identification exacte. L’expérience valide notre approche à étudier le lien entre la signalisation sérotoninergique et pkc-2. En résumé, le but de la thèse était de rechercher la fonction du gène pkc-2 dans les mécanismes moléculaires conduisant à la nécrose musculaire en absence de dystrophine. Les résultats présentés dans la thèse apportent des réponses aux questions fondamentales sur pkc-2 et aussi demandent des expériences supplémentaires afin de élucider plus avant les mécanismes de la dégénérescence musculaire dystrophine-dépendante. / Duchenne Muscular Dystrophy (DMD) is an X-linked progressive muscle disease which is caused by mutations in the dystrophin gene. Until now, there is no effective therapy for DMD. As the largest gene in human beings, it produces a 427-kDa cytoskeleton protein: Dystrophin. Dystrophin links actin and dystrophin associated protein complex (DAPC) in muscles. Currently, there are 3 hypotheses to explain the mechanisms of DMD. They suggest that the absence of dystrophin could lead to periodic muscle cell membrane ruptures, or affect the distribution and function of ion channels, or perturb signal transduction pathways. In Caenorhabditis elegans, there is only one homologue of mammalian dystrophin gene named dys-1, and the nematode protein DYS-1 presents 37% similar to the human one. The double mutant dys-1; hlh-1 exhibits a severe progressive muscle degeneration. The protein composition of the sarcomere has been studied and it has revealed a high degree of similarity with mammalian sarcomere. These allow C. elegans be a relevant animal model to study DMD.To understand why the lack of dystrophin induces muscle degeneration in mammals and worms, and to find new drugs that might help in reducing muscle degeneration, L. Ségalat and his coworkers performed several screens for drugs and genes suppressing muscle degeneration. An interesting gene pkc-2 came out and was considered as a possible regulator in the process of muscle degeneration in C. elegans. The protein that is encoded by this gene in C. elegans is an orthologous of the human gene Protein Kinase C Alpha (PKC), which belongs to the family of serine/threonine specific protein kinases. To study the function of pkc-2, we generated different recombinant constructs, analyzed the expression pattern of pkc-2 with immunocytochemistry, and performed yeast two-hybrid to search for PKC-2 binding partners. In addition, a neurotransmitter serotonin (5-HT) was found by drug screening to be an active blocker of striated muscle degeneration. As C. elegans lacking PKC-2 displays a severe blister phenotype in exogenous 5-HT, studying the correlation between PKC-2 and 5-HT therefore seems to be an opportunity to explore the reasons of muscle degeneration. A genetic screen with EMS (ethane methyl sulfonate) to search serotonin resistant mutant in strain pkc-2 (ok328) would help us study further about the role of pkc-2.In this thesis, different clones myo3::pkc-2 and pkc-2::gfp were made to inject into wild-type animals. The results revealed that pkc-2 expressed intensely in neurons and pharynx, but was not found in body-wall muscles. Mutants dys-1;hlh-1 fed with pkc-2 RNAi did not reduce muscle degeneration statistically comparing to triple mutant pkc-2;dys-1;hlh-1. This indicated that PKC-2 may be dominantly acting in neurons. A yeast two-hybrid screen identified the gene Y59A8A.3, which is a homologue to mammalian filamin A interacting protein 1 isoform 3, as a binding partner of PKC-2. Filamin A is a cytoskeleton protein, anchoring various trans-membrane proteins to the actin cytoskeleton and may also function as an important signaling scaffold. The result suggested that PKC-2 may therefore modulate filamin A activity through the filamin interacting protein 1. Genetic screen by EMS presented 8 candidates named cx253, cx254, cx259, cx263, cx267, cx268, cx270, cx276, which were mapped on chromosomes by SNP mapping using a polymorphic C. elegans strain, but time was too short to identify these genes formally. The experiment also offered possibilities of searching links between PKC-2 and serotonin pathways.In summary, this work studied the gene pkc-2 in order to reveal the function of PKC-2 and its involvement in muscle degeneration. The present results answered some questions about pkc-2, and needed further researches to elucidate the in vivo role of PKC-2 protein and its interaction with other proteins in the mechanism of muscle dystrophy in C. elegans.
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C. elegans, un outil de criblage pour la recherche de traitements contre les maladies raresGiacomotto, Jean 08 March 2010 (has links) (PDF)
Les techniques de criblage actuelles (in vitro et in silico) sont dépendantes des efforts menés en biologie médicinale pour identifier des cibles biologiques pertinentes ; cibles difficiles à définir pour les maladies génétiques dites "perte de fonction". De plus, les composés issus de ces cribles s'avèrent souvent inefficaces et/ou toxiques une fois confrontés à la complexité physiologique d'un organisme entier. Pour contourner ce problème, nous proposons d'utiliser le nématode C. elegans, notamment pour des maladies répondant aux critères suivants : i) physiopathologie complexe et/ou mal comprise excluant le développement à court terme de médicaments sur une base rationnelle, ii) peu d'espoir de thérapie génique/cellulaire à court terme, iii) conservation chez C. elegans du gène relié à la maladie humaine et induisant un phénotype exploitable une fois inactivé. Nous démontrons ici que ce petit nématode permet de tester, à moindre coût, un grand nombre de composés chimiques tout en conservant la complexité physiologique d'un animal entier. De plus, la souplesse génétique de cet animal permet d'apporter rapidement des informations sur le mode d'action des composés identifiés. Ainsi, en plus du but initial visant à identifier des molécules bioactives à intérêt thérapeutique, cette approche peut permettre de dégager de nouvelles cibles moléculaires utiles pour l'industrie chimique, et cruciales pour la recherche de traitements contre les maladies perte de fonction. Finalement, nous présentons comment mettre en place une telle stratégie, notamment pour la myopathie de Duchenne, l'amyotrophie spinale et le syndrome de Schwartz-Jampel. Enfin, nous présentons les résultats obtenus lors des différentes campagnes de criblage, les validations des molécules les plus prometteuses et les travaux effectués pour tenter de comprendre leur mode d'action chez le nématode.
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Développement d'un promoteur efficace et muscle spécifique pour la thérapie génique de la dystrophie musculaire de DuchenneBlain, Marilyne January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
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Avaliação da efetividade e segurança do treinamento da manobra de empilhamento de ar nas distrofinopatias / Evaluation of the effectiveness and safety profile of air stacking in dystrophinopathiesAdriane Sayuri Nakashima Fernandes 27 January 2015 (has links)
INTRODUÇÃO: As distrofias musculares (DM) constituem um grupo de doenças genéticas caracterizadas por fraqueza muscular progressiva decorrente da degeneração irreversível do tecido muscular esquelético. O comprometimento da função respiratória é um sinal precoce da progressão da doença. A fraqueza progressiva dos músculos respiratórios torna o paciente com distrofia muscular incapaz de realizar inspirações profundas de forma independente para promover uma tosse eficaz. Portanto, torna-se necessário fornecer insuflações regulares com volumes que o paciente aprende a empilhar com o fechamento da glote, até que atinja a capacidade de insuflação máxima (CIM). A insuflação pulmonar minimiza complicações, tais como atelectasias e pneumonias, e permite níveis apropriados de ventilação e troca gasosa adequada nas eventuais complicações pulmonares, as quais impõem carga sobre os músculos respiratórios. Este mesmo processo pode representar uma alternativa para otimizar a função respiratória (FP) por meio do aumento do pico de fluxo de tosse (PFT) e manter a complacência pulmonar. Nos pacientes com distrofia muscular causada por mutações do gene da distrofina, a abordagem respiratória aumentou a sobrevida, sendo hoje as complicações cardiovasculares a maior causa de mortalidade. Entretanto, a manobra de empilhamento de ar ainda não foi adequadamente avaliada nestes pacientes. OBJETIVOS: Investigar a efetividade e a segurança desta manobra durante um período de um ano de treinamento em pacientes com Distrofia Muscular de Duchenne (DMD). MÉTODOS: Em 60 pacientes com DMD, cardiopatas e não cardiopatas, foram avaliados a FP, o PFT e a resposta cardíaca como frequência cardíaca (FC), pressão arterial (PA) e sintomas associados, antes, durante a sustentação e após a manobra de empilhamento de ar, em uma primeira avaliação, e depois de um ano de orientação e treinamento. Após o treinamento, foi avaliada, também, a variabilidade da frequência cardíaca (VFC). RESULTADOS: Houve um ganho da Capacidade vital forçada (CVF) e do PFT após um ano de treinamento (p < 0,05), Houve uma correlação linear entre o ganho de CIM e o PFT. Houve diferença na FC e na PA sistólica (PAS) durante a sustentação da manobra em comparação aos outros tempos, sendo que, no grupo de pacientes cardiopatas, a resposta cardíaca foi mais evidente, associada, em alguns pacientes, a sintomas relacionados a baixo débito cardíaco, tais como náuseas e tonturas (p < 0,05). Houve diferença significativa nos valores da VFC durante a manobra. (p < 0,05). CONCLUSÃO: O treinamento da manobra de empilhamento, durante um ano, proporcionou ganho e manutenção da função pulmonar, além de alterações cardíacas significativas associadas a sintomas apenas durante a sustentação da manobra, principalmente nos pacientes cardiopatas / INTRODUCTION: Muscular dystrophy (MD) is a genetic disease characterized by progressive muscle weakness resulting from irreversible degeneration of skeletal muscle tissue. An early sign of disease progression is the impairment of respiratory function. The progressive respiratory muscle weakness makes the patient with muscular dystrophy be unable to perform independent deep breaths in order to promote an effective cough. Therefore, it becomes necessary to provide regular inflations with volumes until it reaches the maximum insufflation capacity (MIC). Pulmonary insufflation minimizes complications such as pneumonia and atelectasis, and allows proper ventilation levels and adequate gas exchange in pulmonary complications. This same process can be an alternative to optimize pulmonary function (PF) by increasing peak cough flow (PCF) and maintain pulmonary compliance. In patients with muscular dystrophy respiratory approach increased their survival. Nowadays, cardiovascular complications is main a leading cause of mortality. However the air stacking has not been adequately evaluated in these patients. OBJECTIVES: To investigate the effectiveness of air stacking exercise and its safety profile in DM. METHODS: We evaluated 60 patients with DMD and with and without heart disease, the PF and PCF; cardiac response as heart rate (HR), blood pressure (BP), and associated symptoms before, during sustained time and after air stacking in the first review, and a year after being advised and trained. After twelve months was also measured the heart rate variability (HRV). RESULTS: There was a statistically difference in forced vital capacity (FVC) and PCF after a year of air stacking (p < 0.05). There was a linear correlation between MIC and PCF (R=0.8). Differences in HR and blood arterial systolic pressure (BPS) at sustainet time of air stacking compared to other times, moreover, in the heart disease group cardiovascular response was more evident, associated in some patients with low cardiac output related symptoms such as nausea and dizziness (p < 0.05). There was a significant difference in HRV values during air stacking (p < 0.05). CONCLUSION: The air stacking for twelvemonths provided gain and maintenance of pulmonary function, beyond a significant cardiac response abnormalities only during sustained time specially in heart disease patients associated with symptoms
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