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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.
451

Avaliação da função do membro superior em pacientes com distrofia muscular de Duchenne / Assessment of upper limb function of patients with Duchenne muscular dystrophies

Artilheiro, Mariana Cunha 24 January 2019 (has links)
Os movimentos do membro superior na distrofia muscular de Duchenne devem ser avaliados para acompanhar a evolução clínica e estabelecer abordagens terapêuticas. Testes que cronometram o desempenho em tarefas funcionais representam uma forma precisa de avaliar a independência funcional e monitorar a progressão da doença. O tempo necessário para a realização de uma tarefa pode refletir a evolução e predizer a habilidade funcional. Contudo, o desempenho pode ser influenciado por movimentos compensatórios, que são comumente adotados para a manutenção da independência funcional. Esta Tese é composta por quatro artigos científicos, que objetivaram: (1) investigar a relação entre as características cinesiológicas, avaliadas pelo teste Performance of Upper Limb e tempo no Teste de Jebsen-Taylor; (2) investigar possíveis diferenças e relações entre o desempenho do membro superior dominante e do membro superior não-dominante de pacientes com distrofia muscular de Duchenne e comparar o desempenho dos pacientes com o de controles saudáveis; (3) descrever a confiabilidade teste-reteste e a consistência interna dos tempos de pacientes com distrofia muscular de Duchenne no Teste de Jebsen-Taylor e (4) comparar os movimentos compensatórios de pacientes e controles saudáveis na tarefa de levar uma colher à boca. Os quatro estudos foram realizados de forma prospectiva observacional. Os resultados mostraram que (1) o Teste de Jebsen-Taylor está correlacionado com o Teste padrão-ouro (Performance of Upper Limb) e o tempo reflete a função motora de membros superiores de pacientes com distrofia muscular de Duchenne; (2) não há diferença na assimetria entre os membros superiores de pacientes quando comparados a indivíduos saudáveis; o desempenho do membro superior dominante é fortemente correlacionado com o do membro superior não-dominante; (3) o Teste de Jebsen-Taylor possui boas propriedades psicométricas e (4) ao levar uma colher à boca, pacientes realizam movimentos compensatórios, como aumento da flexão de cabeça e de cotovelo. Como conclusão, o Teste de Jebsen-Taylor contribui para a avaliação da função motora do membro superior em pacientes com distrofia muscular de Duchenne, por meio da medida do tempo e dos movimentos compensatórios. Os dados normativos apresentados nesta Tese podem ser usados como parâmetros para acompanhamento clínico e terapêutico de pacientes com distrofia muscular de Duchenne / The upper limb movements in Duchenne muscular dystrophy must be evaluated to monitor clinical evolution and establish therapeutic approaches. Tests that measure timed performance on functional tasks represent an accurate way of assessing functional independence and monitoring disease progression. Timed performance can accurately reflect evolution and predict functional skills. However, performance can be influenced by compensatory movements that are commonly adopted to maintain functional independence. This Thesis comprises four articles that aimed to: (1) investigate the relationship between the kinesiological characteristics evaluated by Performance of Upper Limb test and timed performance of the Jebsen-Taylor Test; (2) to investigate possible differences and relationships between the performance of the dominant and the non-dominant upper limbs of patients with Duchenne muscular dystrophy and to compare the performance of patients with healthy controls; (3) describe the timed performance of patients with muscular dystrophy and to investigate the test-retest reliability and internal consistency of the Jebsen-Taylor Test and (4) compare the compensatory movements of patients and healthy controls in bringing a spoon to the mouth. The four studies were observational and prospective. The results showed that (1) Jebsen-Taylor Test is strongly correlated to the gold standard test (Performance of Upper Limb) and timed performance reflects upper limb motor function in patients with Duchenne muscular dystrophy; (2) upper limbs asymmetry in patients with Duchenne muscular dystrophy is not higher than in healthy individuals, and the dominant upper limb performance is strongly correlated to the non-dominant upper limb performance; (3) Jebsen-Taylor test has good psychometric properties and (4) patients perform compensatory movements while bringing a spoon to the mouth, as increased head flexion and increased elbow flexion. In conclusion, Jebsen-Taylor test contributes to upper limb motor function assessment in patients with Duchenne muscular dystrophy, as it measures time and compensatory movements. This thesis provides normative data that can be parameters for clinical and therapeutic follow up of patients with muscular dystrophy
452

Relação entre força muscular e função motora em pacientes com distrofia muscular de Duchenne: acompanhamento de quatro anos / Relationship between muscle strength and motor function in Duchenne muscular dystrophy: follow-up four years

Nunes, Milene Franco de Souza 08 April 2016 (has links)
OBJETIVO: Investigar a relação entre força muscular e função motora, em pacientes com DMD, em um período de 4 anos consecutivos, a partir de avaliações semestrais. MÉTODO: A força muscular foi medida por meio de testes manuais e o cálculo por grupo muscular seguiu o proposto pelo Medical Research Council (MRC) e a função motora pelo método de Medida da Função Motora (MFM), em 43 pacientes (8-30 anos). Foi realizada uma análise descritiva e o teste de correlação de Spearman. Foram investigadas as relações entre pontuações totais e parciais da MRC e da MFM. RESULTADOS: O estudo evidenciou correlações classificadas de moderada a forte relação entre a força muscular e função motora, principalmente com o escore total da MFM e a dimensão D2 (musculatura axial e função motora proximal). Foi encontrada relação negativa moderada entre idade e essas variáveis. CONCLUSÃO: A perda progressiva da função motora tem relação direta e proporcional com a diminuição da força muscular. Quanto maior a idade do paciente, pior sua função motora e força muscular, fornecendo com essa informação, indicadores adicionais da progressão da doença / OBJECTIVE: This study investigated this relationship and examined whether muscle strength and/or motor function would be related to age in DMD. METHODS: Muscle strength was measured by the Medical Research Council scale (MRC) and motor function by the Motor Function Measure (MFM) in 43 patients (8-30 yrs). Spearman tests, descriptive analysis, investigated the relationships between total/ partial scores of MRC and MFM. RESULTS: Total MRC and MFM scores were strongly related to each other and moderately related to age. Many strong relationships between partial MRC and MFM scores were found, mostly between partial MRC scores and MFM dimension 2 (axial and proximal motor function). CONCLUSION: It is possible to predict that the progressive loss of motor function has direct relationship to decreased muscle strength. That the older the patient, the worse their motor function and muscle strength, providing with this information, additional indicators of disease progression
453

Evolução do tempo e dos movimentos compensatórios durante a marcha e o subir e descer degraus em crianças com distrofia muscular de Duchenne / Progression of timed performance and compensatory movements during walking and climbing up and down steps in children with Duchenne muscular dystrophy

Martini, Joyce 22 June 2015 (has links)
Contextualização: O tempo e, mais recentemente, a análise dos movimentos compensatórios, têm sido utilizados na avaliação funcional de crianças com distrofia muscular de Duchenne (DMD). Embora estejam relacionadas, essas duas variáveis podem progredir distintamente em crianças com DMD, no intervalo de um ano. Objetivo: Descrever e comparar a evolução do tempo e dos movimentos compensatórios durante atividades de locomoção em crianças com DMD no período de um ano. Método: Foram avaliados filmes de 32 meninos (média de idade 10 anos) durante a marcha em local plano, por 10 m, o subir e o descer quatro degraus. O tempo foi cronometrado e utilizou-se a escala de avaliação funcional para DMD (Functional Evaluation Scale for Duchenne Muscular Dystrophy, FES-DMD) para pontuar os movimentos compensatórios. Aplicou-se a análise multivariável de variância (MANOVA), com (alfa < 0.05) para comparar as variáveis em três momentos: avaliação inicial (AV0), após 6 meses (AV6) e após 12 meses (AV12). Resultados: Os movimentos compensatórios mais comuns observados durante a marcha foram flexão plantar de tornozelos, aumento da base de apoio, anteriorização de cabeça e tronco e aumento da dissociação de cinturas. Na atividade de subir degraus foram flexão plantar de tornozelos, aumento da base de apoio, hiperlordose lombar e aumento da inclinação lateral do tronco. Ao descer degraus, esses movimentos também foram observados, acrescidos de rotação de tronco, flexão do joelho de apoio, flexão plantar do tornozelo de balanço e descida parando em cada degrau. A MANOVA mostrou que as variáveis aumentaram significativamente no período de um ano (p < 0,05 para todas as comparações) durante a marcha, o subir e o descer degraus. Interações entre o tempo e a pontuação dos movimentos compensatórios evidenciaram progressões distintas durante o subir e descer degraus (p < 0,05 para ambos). Durante a marcha, o tempo aumentou 47% e a pontuação dos movimentos compensatórios aumentou 55%. Ao subir degraus, o tempo aumentou 144% e a pontuação dos movimentos compensatórios aumentou 44%. Durante o descer degraus, o tempo aumentou 186% e a pontuação dos movimentos compensatórios aumentou 58%. Conclusão: Na marcha, as crianças com DMD mostraram aumento discretamente maior dos movimentos compensatórios, quando comparado ao aumento do tempo. Durante o subir e descer degraus, o aumento do tempo foi mais expressivo do que o aumento dos movimentos compensatórios. Acompanhar a evolução do tempo e dos movimentos compensatórios em crianças com DMD permitiu uma avaliação mais precisa e o acompanhamento da progressão das tarefas de locomoção / Introduction: Timed performance and, more recently, compensatory movements, have been used to assess children with Duchenne muscular dystrophy (DMD). Although being strongly related, these variables may progress distinctly within one year. Objective: To describe and compare the progression of timed performance and compensatory movements on locomotion tasks in children with DMD, followed for one year. Method: Films of 32 boys (mean age 10 yrs) performing 10-m walking, climbing up and down four steps were analyzed. Time was digitally measured and compensatory movements were quantified with the Functional Evaluation Scale for DMD (FES-DMD). Multivariate analyses of variance (MANOVAs) (alfa < 0.05) compared the variables on three assessments: initial (A0), after 6 months (A6) and after 12 months (A12). Results: The most common compensatory movements on walking were ankles plantar flexion, increased base of support, head and trunk anteriorization and increased upper and lower body dissociation. On climbing up steps, ankles plantar flexion, increased base of support, lumbar hyperlordosis and excessive trunk lateral inclination. On climbing down steps, these movements were also observed, associated to trunk rotation, stance knee flexion, equinus swing foot and pauses after steps. MANOVAs showed that both variables increased significantly within one year (p < 0.05 for all comparisons) on walking, climbing up and climbing down steps. Interactions between timed performance and compensatory movements evidenced distinct progressions of timed performance and compensatory movements on climbing up and down steps (p < 0.05 for both). On walking, timed performance increased 47% and compensatory movements increased 55%. On climbing up steps, timed performance increased 144% and compensatory movements increased 44%. On climbing down steps, timed performance increased 186% and compensatory movements increased 58%. Conclusion: On walking, children with DMD showed a discrete higher increase of compensatory movements, compared to the increase of timed performance. However, when climbing up and down steps, the timed performance increased much more than the compensatory movements. Evaluating the progression of timed performance and compensatory movements in children with DMD allowed more precise assessment and follow up of locomotion tasks evolution
454

Modelagem neuronal de pacientes com distrofia muscular de Duchenne utilizando células pluripotentes induzidas / Neuronal modelling with Duchenne muscular dystrophy patients using pluripotent stem cells

Fernandes, Isabella Rodrigues 22 April 2015 (has links)
A Distrofia Muscular de Duchenne (DMD) é uma patologia neuromuscular causada pela mutação ou deleção do gene da distrofina, localizado no cromossomo X, levando a degeneração muscular ao longo da vida do paciente. A doença também tem sido associada a déficit cognitivo e falta de habilidade comportamental. Pesquisas com células neurais de pacientes com DMD poderiam ajudar a elucidar os sintomas neurológicos associados. Neste trabalho, através de células-tronco pluripotentes induzidas (iPSC) derivadas da polpa de dente decíduo esfoliado (SHED) de pacientes com DMD modelamos a DMD produzindo células neurais vivas in vitro. A expressão da distrofina foi verificada durante e após a diferenciação neuronal e nos ensaios de imunofluorescência, mostrando que essa proteína está presente em células do SNC. Na análise gênica através do qPCR, a Dp71 e a Dp140, isoformas da distrofina, apresentavam uma expressão menor do que os controles. Além disso, as análises das sinapses baseada na colocalização de marcadores pré e pós-sinápticos (Sinapsina1 e Homer 1) revelaram que os neurônios dos pacientes com DMD tinham menor quantidade de sinapses que os controles, reforçando o papel da distrofina no SNC. Logo, a expressão de genes relacionados a plasticidade sináptica revelou 10 genes alterados nos neurônios dos pacientes DMD, sugerindo que a mutação no gene da distrofina possivelmente altera a plasticidade sináptica e pode estar envolvida na habilidade cognitiva destes pacientes. Desta forma, com base nos nossos achados, a modelagem neuronal de DMD é factível e pode auxiliar a elucidar os mecanismos da fisiopatologia da doença / The Duchenne muscular dystrophy (DMD) is a neuromuscular disorder caused by a mutation or deletion of the dystrophin gene located on the X chromosome, leading to muscle degeneration throughout the patient\'s life. The disease has also been associated with cognitive impairment and lack of behavioral skill. Research on neural cells from patients with DMD could help to elucidate the neurological symptoms associated. In this work, through induced pluripotent stem cells (iPSC) derived from dental pulp exfoliated (SHED) of patients with DMD model the DMD producing living neural cells in vitro. The dystrophin expression was observed during and after neuronal differentiation and immunofluorescence assays, showing that this protein is present in CNS cells. In gene analysis by qPCR, the Dp71 and Dp140, isoforms of dystrophin, had a lower expression than controls. Furthermore, based on analysis of synapses colocalization pre and postsynaptic markers (Synapsin1 and Homer 1) showed that neurons of DMD patients had lower number of synapses controls, supporting a role for dystrophin in the CNS. Finally, the expression of synaptic plasticity related genes wasfound in 10 genes altered in neurons of DMD patients, suggesting that the mutation of the dystrophin gene possibly alters synaptic plasticity and may be involved in cognitive ability of these patients. Finally, based on our findings, neuronal modeling DMD is feasible and may help elucidate the mechanisms of pathophysiology of the disease
455

Common and distinct immunological aspects in acquired inflammatory myopathies and inherited muscular dystrophy

Preuße, Corinna 08 December 2014 (has links)
Die heterogene Gruppe der Myopathien kann sowohl die Funktion des Muskels beeinflussen, als auch andere Organsysteme. Erworbenen Muskelerkrankungen sind theoretisch behandelbar, jedoch stehen zumeist nur sehr unspezifische Behandlungsoptionen zur Verfügung, während für vererbte Formen bisher keine kausalen Therapiemöglichkeiten bekannt sind. In dieser Arbeit wurden drei verschiedene Muskelerkrankungen untersucht. Gemeinsam ist ihnen ein jeweils charakteristischer Einstrom von Entzündungszellen, wobei die Zusammensetzung des Zellinfiltrates (z.B. Lymphozyten oder Makrophagen) bei den verschieden Erkrankungen unterschiedlich war. Weiterhin unterscheidet sich das zugrunde liegende Zytokinmilieu für die einzelnen untersuchten Entitäten. Daher war es Ziel der Arbeit, die genauen Interaktionen zwischen den Immunzellen zu untersuchen, sowie die charakteristischen Phänomene der Erkrankungen (Hypoxie, Entzündung und Fibrose). Nekrotisierende Myopathien können sowohl durch eine immun-vermittelte Genese, als auch durch Kontakt mit toxischen Substanzen ausgelöst werden und beide Subgruppen können klar durch morphologische Kriterien, als auch durch spezielle Immunaspekte unterschieden werden. Makrophagen waren hier die vorherrschende Zellpopulation und im gesamten Muskel verteilt. Patienten mit Dermatomyositis dagegen zeigten ein typisches perifaszikuläres Atrophiemuster und hypoxische Effekte, wobei beide Phänomene deutlich ausgeprägter bei juvenilen, als bei adulten Patienten vorkamen. Erbliche Myopathien (z.B. Muskeldystrophie Duchenne) können ebenfalls entzündliche Infiltrate aufweisen und die Entwicklung von Fibrose in der Skelettmuskulatur ist dabei ein Hauptkriterium der Muskelfaserdegeneration. Ein neu entwickelter computer-basierter Algorithmus wurde genutzt, um diese Entwicklung zu quantifizieren. Die Menge an Bindegewebe steigt mit dem Alter der Patienten, während bei älteren Patienten außerdem ein fettgewebiger Umbau ein wichtiger Aspekt der Pathologie war. / The heterogeneous group of myopathies can affect the skeletal muscle or other organ systems and comprise a huge number of different entities. Acquired myopathies are potentially treatable, but there are often only unspecific treatment options, while there is no causative cure for inherited forms of myopathies. In this work, three different entities were analyzed, which all share common aspects of the immune response, but also feature distinct immunological aspects as well. They have an inflammatory part in common, which is mainly regulated by influx of immune cells. However, the composition of these cellular infiltrates (e.g. lymphocytes or macrophages) was varying between the diseases. In addition, the respective cytokine milieu was highly specific in the examined entities. Thus, the aim of the study was to precisely examine interactions between immune cells, and analyze characteristic pathological phenomena (hypoxia, inflammation and fibrosis). Necrotizing myopathies have an immune-mediated background or showed a toxic aetiology and both sub-groups can be distinguished by their morphological characteristics and certain immune aspects. Here macrophages are the predominant cell population and are spread throughout the muscle. Analyses of patients suffering from dermatomyositis showed a typical perifascicular pattern of atrophy, as well as effects of hypoxia and the described features are in general more pronounced in juvenile dermatomyositis than in the adult form. Inherited myopathies (e.g. Duchenne muscular dystrophy) harbor significant inflammatory infiltrates as well and development of fibrosis was a major feature of skeletal muscle degeneration. A computer-based algorithm was used to quantify fibrosis. The amount of connective tissue increased with the age of patients, while at late stage of disease fatty transformation was an additional important issue.
456

Role of vascular plasticity in muscle remodeling in the child / Rôle de la plasticité vasculaire dans le remodelage musculaire chez l’enfant

Gitiaux, Cyril 27 March 2015 (has links)
Le muscle strié squelettique est un tissu richement vascularisé. Au delà de l'apport en oxygène et en nutriments, de nouvelles fonctions des vaisseaux ont été récemment identifiées, par le biais des interactions établies entre les cellules du vaisseau (cellules endothéliales) et les cellules du muscle, en particulier les cellules souches musculaires (cellules satellites). Celles-ci interagissent étroitement avec les cellules endothéliales pour leur expansion et leur différenciation, puis avec les cellules péri-endothéliales pour leur auto-renouvellement et leur retour à la quiescence. Les vaisseaux participent ainsi au contrôle de l’homéostasie du muscle squelettique. Grâce à ces interactions, les cellules vasculaires jouent donc un rôle central dans le remodelage tissulaire après un phénomène destructif, survenant par exemple au cours d’un trauma ou d’une myopathie. Pour étudier, les mécanismes de la plasticité vasculaire au cours du remodelage tissulaire, deux situations paradigmatiques de muscle en régénération chez l’enfant : la dermatomyosite juvénile (DMJ) et la dystrophie musculaire de Duchenne (DMD) ont été étudiées. Il existe, dans ces deux pathologies une souffrance musculaire associée à des cycles de nécrose/régénération. Elles se différencient par leur plasticité vasculaire et par leur évolution. En effet, la DMJ, la myopathie inflammatoire la plus fréquente de l’enfant est caractérisée par une vasculopathie avec perte en capillaires. L’évolution peut être favorable avec restitution ad integrum du muscle. La DMD est une myopathie génétique conduisant à une dégradation progressive de la force musculaire associée à une néovascularisation compensatrice. Le volet clinique/histologique incluant une analyse multiparamétrique des critères évolutifs cliniques et de réponse thérapeutique couplée à une réévaluation des données histologiques de la DMJ (analyse morphométrique des muscles DMJ) a permis de montrer qu’il existait des sous groupes phénotypiques homogènes de sévérité différente dans la DMJ. Le degré de sévérité clinique est relié à la gravité de la vasculopathie musculaire Par ailleurs, des marqueurs cliniques et histologiques simples permettant de repérer au diagnostic les patients nécessitant une escalade thérapeutique rapide (CMAS>34, atteinte gastrointestinale, fibrose endomysiale musculaire au diagnostic) ont été identifiés. Le volet cellulaire a permis l’identification in vitro des interactions cellulaires spécifiques et différentielles des myoblastes issues de patients DMD et DMJ sur les cellules endothéliales normales par l’analyse de leur rôle sur la prolifération, migration et différenciation des cellules vasculaires. Dans la DMD, les myoblastes entrainent une réponse angiogénique importante mais non efficace (néovascularisation anarchique). Dans la DMJ, les myoblastes participent efficacement à la reconstruction vasculaire notamment via la sécrétion de facteurs proangiogéniques. Ces résultats ont été renforcés par analyse transcriptomique effectuée à partir de cellules endothéliales et satellites isolées de muscles de patients confirmant le rôle central de la vasculopathie associée à un contexte inflammatoire spécifique lié à l’interféron dans la physiopathologie de la DMJ et montrant dans la DMD une dérégulation de l’homéostasie normale des interactions vaisseau-muscle avec mise en jeu d’un remodelage tissulaire non efficace. Ces données permettent d'identifier de nouvelles fonctions des cellules vasculaires dans le remodelage du muscle strié squelettique au cours des pathologies musculaires de l'enfant, et devraient ouvrir la voie à de nouvelles approches thérapeutiques. / Skeletal muscle is highly vascularised. Beyond oxygen and nutriment supply, new functions for vessels have been recently identified, through the interactions that vessel cells (endothelial cells) establish with muscle cells, particularly with muscle stem cells (satellite cells). These latter closely interact with endothelial cells for their expansion and their differentiation, then with periendothelial cells for their self-renewal and return to quiescence. During skeletal muscle regeneration endothelial cells reciprocally interact with myogenic cells by direct contact or by releasing soluble factors to promote both myogenesis and angiogenesis processes. Skeletal muscle regeneration typically occurs as a result of a trauma or disease, such as congenital or myopathies. To better understand the role of vessel plasticity in tissue remodeling, we took advantage of two muscular disorders that could be considered as paradigmatic situations of regenerating skeletal muscle in the child: Juvenile Dermatomyositis (JDM), the most frequent inflammatory myopathy and Duchenne Muscular Dystrophy (DMD), the most common type of muscular dystrophy. Although these two muscular disorders share, at the tissue level, similar mechanisms of necrosis-inflammation, they differ regarding the vessel domain. In JDM patients, microvascular changes consist in a destruction of endothelial cells assessed by focal capillary loss. This capillary bed destruction is transient. The tissue remodeling is efficient and muscle may progressively recover its function. By contrast, in DMD, despite an increase of vessels density in an attempt to improve the muscle perfusion, the muscle function progressively alters with age. We identified clinical and pathological markers of severity and predictive factors for poor clinical outcome in JDM by computing a comprehensive initial and follow-up clinical data set with deltoid muscle biopsy alterations controlled by age-based analysis of the deltoid muscle capillarization. We demonstrated that JDM can be divided into two distinctive clinical subgroups. The severe clinical presentation and outcome are linked to vasculopathy. Furthermore, a set of simple predictors (CMAS<34, gastrointestinal involvement, muscle endomysial fibrosis at disease onset) allow early recognition of patients needing rapid therapeutic escalation with more potent drugs. We studied in vitro the specific cell interactions between myogenic cells issued from JDM and DMD patients and normal endothelial cells to explore whether myogenic cells participate to the vessel remodeling observed in the two pathologies. We demonstrated that MPCs possessed angiogenic properties depending on the pathological environment. In DMD, MPCs promoted the development of establishment of an anarchic, although strong, EC stimulation, leading to the formation of weakly functional vessels. In JDM, MPCs enhanced the vessel reconstruction via the secretion of proangiogenic factors. This functional analysis was supported by the transcriptomic analysis consistent with a central vasculopathy in JDM including a strong and specific response to an inflammatory environment. On the contrary, DMD cells presented an unbalanced homeostasis with deregulation of several processes including muscle and vessel development with attempts to recover neuromuscular system by MPCs. To summarize, our data should allow the definition of new functions of vessel cells in skeletal muscle remodelling during muscle pathologies of the child that will open the way to explore new therapeutic options and to gain further insights in the pathogenesis of these diseases.
457

Développement d'une stratégie thérapeutique pour la dystrophie facio-scapulo-humérale. / Development of a therapeutic strategy for facioscapulohumeral muscular dystrophy

Marsollier, Anne-Charlotte 08 June 2017 (has links)
La dystrophie facio-scapulo-humérale (FSHD) est une maladie musculaire autosomique dominante rare. Cette pathologie est causée par la perte des marques épigénétiques répressives au macrosatellite D4Z4 en région subtélomérique du chromosome 4, ce qui conduit à la relaxation de la chromatine, l’expression aberrante du facteur de transcription DUX4 et la dérégulation de centaines de gènes. A ce jour, aucun traitement thérapeutique n’existe pour la FSHD. Le but de ce projet était de déterminer si cibler ou non par des oligonucléotides antisens (AOs) les séquences clés impliquées dans la polyadénylation des ARNm peut-être une stratégie thérapeutique pour inhiber l’expression de DUX4 chez les patients FSHD. En effet, le clivage et la polyadénylation en 3’ des ARNm sont des mécanismes fondamentaux de la maturation des ARNm nécessaires à leur export nucléaire, leur stabilité ou leur traduction efficace. Ces mécanismes représentent donc des cibles intéressantes pour une suppression de l’expression d’un gène dans des maladies à gain de fonction. Pour la première fois, nous avons pu montrer in vitro que l’utilisation d’AOs ciblant les séquences clés impliquées dans l’ajout d’une queue poly(A), notamment le signal de polyadénylation ou le site de clivage, conduit à une sous-expression de l’ARNm gène ciblé, et en particulier DUX4. Les AOs présentant in vivo une faible capacité à pénétrer les cellules et une forte clairance, les séquences des AOs les plus prometteurs ont été insérées dans un vecteur AAV sous promoteur U7. Les premiers résultats obtenus avec ces vecteurs sur un modèle murin sont prometteurs. Cette stratégie innovante apparait comme une option thérapeutique pour la FSHD. / FacioScapuloHumeral Dystrophy (FSHD) is a rare autosomal dominant neuromuscular disorder. This disease is caused by a loss of epigenetic marks within the D4Z4 macrosatellite located in the subtelomeric region of chromosome 4 leading to chromatin relaxation, aberrant expression of the DUX4 transcription factor and a cascade of gene deregulations. So far, there is no curative treatment for FSHD. The aim of this project was to determine whether or not targeting 3’-end key sequences involved in the polyadenylation of mRNA by antisens oligonucleotides (AOs) can be used as an efficient strategy for DUX4 gene silencing in FSHD. Indeed, cleavage and polyadenylation of the 3’-end of mRNAs are fundamental mechanisms of mRNAs maturation required for nuclear export, stability of the mRNAs and efficient translation and consequently could represent interesting targets for suppression of gene expression for gain of function diseases. For the first time, we demonstrated in vitro that targeting 3’-end key sequences involved in the addition of the poly(A) tail, such as the polyadenylation signal and the cleavage site, leads to an efficient extinction of the mRNA targeted and in particular DUX4. Because AOs have a weak cellular uptake and a rapid clearance in vivo, the sequences of the most promising AOs have been vectorised into an AAV vector under the control of the U7 promoter. The first results that we obtained with a FSHD mouse model treated with these vectors are promising. This innovating strategy appears as a therapeutic option for FSHD.
458

Evolução do tempo de execução e dos movimentos compensatórios nas atividades de sentar e levantar da cadeira em crianças com distrofia muscular de Duchenne / Evolution of timed performance and compensatory movements of sitting and rising from a chair in children with Duchenne muscular dystrophy

Simões, Mariene Scaranello 12 December 2016 (has links)
Contextualização: Devido ao aumento progressivo da fraqueza muscular na DMD, novos movimentos compensatórios e variação no tempo de execução de atividades funcionais são utilizados para prolongar a atividade funcional. Objetivos: Descrever a evolução dos movimentos compensatórios, observados nas atividades de sentar e de levantar da cadeira em crianças com DMD durante um ano. Comparar e correlacionar a evolução do tempo de execução dessas atividades com o número de movimentos compensatórios, e analisar a responsividade do tempo de execução dessa atividade em análise semestral, durante um ano. Método: Foram acompanhadas 23 crianças com DMD, deambulantes, com idade entre 5 e 12 anos, por um ano. Foram estudadas as atividades de sentar e de levantar da cadeira em 3 momentos (inicial, após seis e após doze meses) por meio da Escala de Avaliação Funcional para DMD (FES-DMD-D1). Utilizou-se ANOVAs para comparar a evolução do tempo de execução e do número movimentos compensatórios (escores das fases e subfases da FES-DMD-D1). O teste post hoc de Tukey foi utilizado quando identificado efeito principal significativo e o teste de Spearman, para correlacionar essas variáveis. A responsividade do tempo de execução foi analisada por meio do teste de tamanho do efeito (ES) e a média de resposta padronizada (MRP). Resultados: A evolução das atividades de sentar e de levantar da cadeira ao longo de 12 meses apresentou aumento significante do número dos movimentos compensatórios e do tempo de execução. Somente a atividade de levantar apresentou correlação de moderada a forte com o tempo de execução, e o tempo de execução desta atividade foi responsivo a partir de seis meses. Conclusão: Houve aumento progressivo do número dos movimentos compensatórios e do tempo de execução das atividades de sentar e levantar da cadeira, no período de um ano. Somente o levantar da cadeira apresentou correlação entre as variáveis estudadas. Para uma avaliação mais precisa da progressão da doença, sugerimos acompanhamento do tempo de execução da atividade de levantar da cadeira e, sempre que possível acompanhada da análise de presença de movimentos compensatórios / Background: With the progressive increase of muscle weakness in patients with DMD, new compensatory movements are employed to maintain the performance of functional activities. Objective: To describe the evolution of compensatory movements observed in sitting and rising from a chair in children with DMD. Compare and correlate the evolution of timed performance of these activities and the number of compensatory movements in one year. To analyze the responsiveness of timed performance in six-month and one year intervals. Method: Twenty-three ambulatory children with DMD, aged 5 to 12 years, were followed during one year. Sitting and rising from a chair were evaluated in three moments (initial assessment, after six and after twelve months) with the Functional Assessment Scale for DMD, domain 1 (FES-DMD-D1). Analyses of variance (ANOVA) compared the timed performances and numbers of compensatory movements (scores on the phases and subphases of FES-DMD-D1). Post hoc Tukey tests were used when a significant main effect was identified and the Spearman test was used to correlate these variables. Responsiveness of the timed performance was described by the effect size (ES) and the standardized response mean (SRM). Results: The progression of sitting and rising from a chair in one year resulted in a significant increase in FES-DMD-D1 scores and timed performance. Only rising from a chair showed moderate to strong correlation with timed performance. Timed performance was responsive in six months and one year reassessments. Conclusion: There was a progressive increase in the number of compensatory movements and timed performance of sitting and rising from a chair. Only rising from a chair showed correlation between compensatory movements and timed performance. For a more accurate assessment of DMD progression, we suggest monitoring the timed performance of rising from a chair and, whenever possible, scoring the compensatory movements
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Caracterização de células tronco germinativas caninas para o tratamento da distrofia muscular do Golden Retriever (GRMD) / Characterization of canine embryonic germ cells for the treatment of the muscular dystrophy in Golden Retriever (GRMD)

Martins, Daniele dos Santos 20 December 2006 (has links)
A domesticação dos cães produziu-se simultaneamente em várias partes do globo o que ocasionou, o aparecimento por seleção de várias raças. Desde então o cão passou a ser utilizado para várias e diferentes tarefas, dentre elas acompanhar o homem, que usufruiu da sua conveniência, descobrindo que muitas vezes ambos podem sofrer dos mesmos males. Cães da raça Golden Retriever apresentam uma doença geneticamente degenerativa, homóloga a distrofia muscular de Duchenne (DMD) no homem; ambas doenças afetam o gene que produz a distrofina; uma proteína citoesquelética múscular. Uma possível forma de fornecer uma cópia normal do gene para os grupos musculares afetados de um indivíduo consiste no transplante de células tronco os quais podem ser obtidas de células embrionárias, células germinativas, células do sangue de cordão umbilical, células de medula óssea e células de sangue periférico. Estudos com modelos animais tem mostrado que transplante de células tronco fetais ou células tronco pluripotentes podem ter sucesso no tratamento de muitas doenças crônicas, sendo assim, objetivamos delinear uma linha de tratamento para distrofia muscular em cães da raça Golden Retriever, mediante caracterização e uso das células germinativas embrionárias para terapia celular. Foram utilizados 16 fêmeas sem raça definida (SRD), e as cadelas foram selecionadas a partir do exame citológico; as fêmeas foram inseminadas artificialmente, e após 30 dias de gestação os animais foram castrados pela técnica de ovário-salpingohisterectomia. Os embriões coletados possibilitaram a obtenção e estabelecimento de células tronco germinativas embrionárias, de fibroblastos fetais, de células musculares, os quais analisamos através de citometria de fluxo, interação no co-cultivo de células musculares caninas e células germinativas embrionárias e a imunopositividade das células na detecção de Oct-4. Os resultados nos possibilitam afirmar que em embriões com 22 dias de idade gestacional a região paramesonéfrica apresenta-se indiferenciada, diferentemente do que encontramos com 24 dias de idade, no qual o rim primitivo apresenta-se visível diferenciado. As células tronco germinativas embrionárias apresentaram colônias compactas e com alta proliferação de células mononucleares indiferenciadas e que as células tronco germinativas embrionárias apresentaram como principal problema a manutenção das culturas por períodos significativos. / The canine domesticity generated simultaneously in different parts of the World, that created, the begin of selection of many breeds. Since that time, dogs become to be used for different works, since follow men, that usufructed their convinience discovering most of the time that both are soffering the same ill. Dogs from the Golden Retriever breed presented a degenerative and genetically disease, homologous to Duchenne Muscular Dystrophy (DMD) in human, the dystrophin gene affection; a muscle citosckeletical protein. A possibility way to supply a correct gene shape for the affected muscle could be from the stem cell therapy from embrionic stem cell, germ cells, umbilical cord blood cells, bone marrow and perific blood. Researches with animal models are showing sucess on the treatment with fetal stem cells or pluripotents ones in different types of cronic illness, then, we aimed a treatment of the Golden Retriever Muscular Dystrophy using embrionic germ cells meantime characterization and their use on cell therapy. Were uses 16 females crossbreed (SRD), bitches were selected by the vaginal cytology exams; females were artificially inseminated and after 30 days of pregancy, the animals were histectomized. Embryos were collected to stabilish embrionic germ cells, canine fibroblasts, muscle cells, which were analysed by flow cytometre, co culture and OCT-4 detection. The results showed the paramesonephic region of embryos with 22 days of pregnancy presents undifferentiate cells(germ cells), what differs from embryos with 24 days, which primitive kidneys presented differentianted types of cells. Under culture conditions, these cells formed compact colonies with high proliferative potential, but without capacity of maintenance after 30 days.
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Determinação de elementos de relevância clínica em tecidos biológicos decamundongos distróficos Dmdmdx/J por AAN / Elements determination of clinical relevance in biological tissues of Dmdmdx/j dystrophic mice strains investigated by NAA

Metairon, Sabrina 14 March 2012 (has links)
Neste trabalho a determinação de elementos químicos em tecidos biológicos (sangue total, ossos e orgãos) de camundongos distróficos, usados como modelo animal da Distrofia Mucular de Duchenne (DMD), foi realizada utilizando técnica analítica nuclear. O objetivo do presente trabalho foi a determinação dos valores de referência para elementos de relevância em bioquímica clínica (Ca, Cl, K, Mg e Na) e nutricional (Br e S) em sangue total, tíbia, quadríceps anterior e coração de camundongos da linhagem distrófica Dmdmdx/J (10 machos e 10 fêmeas) e grupo controle C57BL/6J (10 machos), utilizando a técnica de Análise por Ativação com Nêutrons AAN. Para obter mais detalhes das alterações que esta disfunção pode causar nesses tecidos biológicos, foram calculadas matrizes de correlação entre as espécies Dmdmdx/J e comparadas ao grupo controle C57BL/6J. Para a realização deste estudo 119 amostras de tecidos biológicos foram irradiadas no reator nuclear IEA-R1 no IPEN (São Paulo, Brasil). Os resultados de análise, por AAN, constituem as primeiras estimativas para os valores de referência nesses tecidos biológicos dos camundongos Dmdmdx/J e C57BL/6J. Além disso, as alterações em alguns dos coeficientes de correlações entre os animais saudáveis e com disfunção indicam uma conexão entre esses elementos no sangue, tíbia, quadríceps e coração. Esses dados poderão auxiliar pesquisadores avaliar e comparar as vantagens e desvantagens dos diferentes tratamentos, realizados na distrofia muscular, quando estes modelos animais forem empregados, auxiliando os pesquisadores a avaliar a eficácia de novos procedimentos terapêuticos antes de serem empregados em paciente com DMD. / In this work the determination of chemistry elements in biological tissues (whole blood, bones and organs) of dystrophic mice, used as animal model of Duchenne Muscular Dystrophy (DMD), was performed using analytical nuclear technique. The aim of this work was to determine reference values of elements of clinical (Ca, Cl, K, Mg, Na) and nutritional (Br and S) relevance in whole blood, tibia, quadriceps and hearts from Dmdmdx/J (10 males and 10 females) dystrophic mice and C57BL/6J (10 males) control group mice, using Neutron Activation Analysis technique (NAA). To show in more details the alterations that this disease may cause in these biological tissues, correlations matrixes of the DMDmdx/J mouse strain were generated and compared with C57BL/6J control group. For this study 119 samples of biological tissue were irradiated in the IEA-R1 nuclear reactor at IPEN (São Paulo, Brazil). The concentrations of these elements in biological tissues of Dmdmdx/J and C57B/6J mice are the first indicative interval for reference values. Moreover, the alteration in some correlation coefficients data among the elements in the health status and in the diseased status indicates a connection between these elements in whole blood, tibia, quadriceps and heart. These results may help the researchers to evaluate the efficiency of new treatments and to compare the advantages of different treatment approaches before performing tests in patients with muscular dystrophy.

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