Skeletal muscle dysfunction in chronic obstructive pulmonary disease (COPD) is a condition in which peripheral skeletal muscle undergoes myopathic changes which impair muscle function, limit physical performance, and can lead to significant disability. While the etiology of the dysfunction is unknown, this study was conducted to test the hypothesis that chronic hypoxemia leads to alterations in oxygen transport and muscle function. A primary objective was to validate elastase-induced emphysema in rats as an animal model of skeletal muscle dysfunction in COPD.Arterial blood gases were used to determine the severity of hypoxemia and sodium dodecyl sulfate- polyacrylamide gel electrophoresis was used to determine the proportions of myosin heavy chain isoforms I, IIa, IIx, and IIb. Measures of microvascular oxygenation and blood flow in the spinotrapezius muscle allowed for determination of both convective and diffusive oxygen supply to the muscle, as well as calculation of muscle oxygen consumption at rest and during electrically stimulated three-minute muscle contractions. Muscle performance measures included peak force, force-time integral, and fatigue index. Due to a presumed rat respiratory virus, which likely resulted in the control group being nearly as hypoxemic as the elastase-induced emphysema group, this study was not able to definitively test the hypothesis that chronic hypoxemia leads to both a diminished supply and demand of oxygen in skeletal muscle. Although many of the results of the present study were not statistically significant, they exhibited consistent trends over time and are likely of physiological significance. All measures of muscle performance were lower in the emphysema group. In addition, spinotrapezius muscle oxygen consumption and blood flow were lower in the emphysema group. The addition of supplemental oxygen during isolated, small-muscle mass exercise did increase the force-time integral by ~18% in both groups, suggesting that muscle work in these hypoxemic animals may be limited by oxygen supply. Thus, the data on muscle fiber type, oxygen consumption and muscle performance suggest that elastase-induced emphysema in rats leads to a similar skeletal muscle dysfunction that is observed in humans with COPD, and indicates that it is a valid animal model of skeletal muscle dysfunction in COPD.

Made available in DSpace on 2014-06-11T19:22:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-10Bitstream added on 2014-06-13T18:49:42Z : No. of bitstreams: 1 fosco_lc_me_prud.pdf: 905074 bytes, checksum: 4682160d9d51bca48d98f5cdd23c2d6d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A inflamação sistêmica é um fator relevante na disfunção dos músculos esqueléticos de indivíduos com doença pulmonar obstrutiva crônica (DPOC). Esta disfunção pode ser revertida parcialmente por meio de treinamento físico que, contudo, provoca respostas imunes dependentes de vários fatores, entre eles, o tipo, a intensidade e a duração do exercício. Objetivo: avaliar respostas inflamatórias, bem como níveis de força muscular e valores de massa magra em pacientes com DPOC sem tratamento prévio, comparando dois protocolos de treinamento resistido. Casuística e métodos: 24 indivíduos com diagnóstico de DPOC confirmado por espirometria foram alocados em dois grupos: 12 indivíduos realizaram um treino resistido tradicional (RT) e 12 indivíduos, treino resistido com cordas elásticas (RE). A frequencia do treinamento foi de três vezes por semana, com duração de oito semanas consecutivas. Para a quantificação dos níveis plasmáticos do Fator de Necrose Tumoral alfa (TNF-α), Interleucina 1β (IL-1β) e Interleucina 10 (IL-10)... / Systemic inflammation is an important factor in skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease (COPD). This dysfunction can be reversed partially by means of physical training, however, that causes immune responses depend on various factors including the type, intensity and duration of exercise. Objective: Objective: To evaluate the inflammatory responses, as well as levels of muscle strength and fat-free mass values in COPD patients without prior treatment, comparing two protocols of resistance training. Casuistic and methods: 24 subjects with a diagnosis of COPD confirmed by spirometry were divided into two groups: 12 patients underwent conventional resistance training (RT) and 12 subjects, resistance training with elastic bands (RE); the training was executed three times a week during eight consecutive weeks. For the quantification of plasma levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β) and interleukin 10 (IL-10) ... (Complete abstract click electronic access below)

Orientador: Ercy Mara Cipulo Ramos / Banca: Dionei Ramos / Banca: José Roberto Jardim / Resumo: A inflamação sistêmica é um fator relevante na disfunção dos músculos esqueléticos de indivíduos com doença pulmonar obstrutiva crônica (DPOC). Esta disfunção pode ser revertida parcialmente por meio de treinamento físico que, contudo, provoca respostas imunes dependentes de vários fatores, entre eles, o tipo, a intensidade e a duração do exercício. Objetivo: avaliar respostas inflamatórias, bem como níveis de força muscular e valores de massa magra em pacientes com DPOC sem tratamento prévio, comparando dois protocolos de treinamento resistido. Casuística e métodos: 24 indivíduos com diagnóstico de DPOC confirmado por espirometria foram alocados em dois grupos: 12 indivíduos realizaram um treino resistido tradicional (RT) e 12 indivíduos, treino resistido com cordas elásticas (RE). A frequencia do treinamento foi de três vezes por semana, com duração de oito semanas consecutivas. Para a quantificação dos níveis plasmáticos do Fator de Necrose Tumoral alfa (TNF-α), Interleucina 1β (IL-1β) e Interleucina 10 (IL-10) ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Systemic inflammation is an important factor in skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease (COPD). This dysfunction can be reversed partially by means of physical training, however, that causes immune responses depend on various factors including the type, intensity and duration of exercise. Objective: Objective: To evaluate the inflammatory responses, as well as levels of muscle strength and fat-free mass values in COPD patients without prior treatment, comparing two protocols of resistance training. Casuistic and methods: 24 subjects with a diagnosis of COPD confirmed by spirometry were divided into two groups: 12 patients underwent conventional resistance training (RT) and 12 subjects, resistance training with elastic bands (RE); the training was executed three times a week during eight consecutive weeks. For the quantification of plasma levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β) and interleukin 10 (IL-10) ... (Complete abstract click electronic access below) / Mestre

La réhabilitation respiratoire tient une place importante dans la prise en charge des patients atteints de Broncho-pneumopathie chronique obstructive (BPCO) stables en induisant des bénéfices au niveau de la tolérance à l’effort, la fonction et la masse musculaire périphérique. La présence d’un stress oxydant élevé à l’état basal, considéré comme un des principaux facteurs impliqués dans l’atteinte musculaire périphérique, est bien admise malgré les discordances rapportées dans la littérature notamment au niveau du système antioxydant. L’absence d’amélioration des marqueurs du stress oxydant au cours d’un programme de réhabilitation respiratoire constitue une limite probable aux adaptations musculaires escomptées. Cependant, même si une supplémentation en antioxydants semble être une intervention adaptée permettant de réduire le stress oxydant et d’améliorer l’atteinte musculaire périphérique, son efficacité reste toujours à prouver chez les patients BPCO.Ainsi, nos objectifs étaient de déterminer et caractériser l’hétérogénéité des marqueurs du stress oxydant en vue d’étudier les effets d’une supplémentation en antioxydants adaptée sur des marqueurs spécifiques de l’atteinte musculaire périphérique des patients BPCO stables. A travers une analyse globale intégrant toute la complexité du stress oxydant, ce travail de thèse a montré que les principaux déficits en antioxydants chez les patients BPCO stables se situent au niveau de l’équilibre vitamine C/E, du zinc et du sélénium. De plus, nos résultats ont permis de déterminer des profils de patients caractérisés notamment par des sous-groupes de femmes ayant une majoration des taux de peroxydes lipidiques. Basé sur les principaux déficits identifiés et malgré l’importante hétérogénité des réponses, nous avons montré qu’une supplémentation en antioxydants permettait d’optimiser les bénéfices d’un programme de réhabilitation respiratoire en améliorant la FMIV, la Vo2sl et la surface de section transversale (SSt) des fibres musculaires de patients BPCO stables. Ainsi, dans l’optique d’une approche par phénotypes, l’utilisation de valeurs de références de la SSt, comme établies dans notre seconde étude, semble constituer un biomarqueur adapté mais celles-ci doivent être optimisées afin d’être applicable chez les patients BPCO. Pour conclure, outre l’intérêt pour l’utilisation d’une supplémentation en antioxydants au cours d’un programme de réhabilitation respiratoire, nos résultats contribuent à améliorer les connaissances sur le rôle du stress oxydant dans la physiopathologie de l’atteinte musculaire périphérique des patients BPCO. De plus, une meilleure compréhension et caractérisation de l’hétérogénéité, à la fois du stress oxydant et de l’atteinte musculaire périphérique, ouvrent des perspectives de recherche prometteuses dans l’optique d’une adaptation de la prise en charge des patients BPCO. / Pulmonary rehabilitation is considered as a major component in the management of chronic obstructive pulmonary disease (COPD) patients by inducing benefits on exercise capacity, peripheral function and muscle mass. Elevated oxidative stress at baseline, considered as one of the main factors involved in peripheral muscle impairment, is well accepted despite the discrepancies reported in the literature especially on antioxidant system. The absence of oxidative stress marker improvement following a pulmonary rehabilitation program is a likely limit to the expected muscle adaptations. However, although antioxidant supplementation seems to be an appropriate intervention for reducing oxidative stress and improving peripheral muscle impairment, its effectiveness remains to be proven in COPD patients.Thus, our objectives were to determine and characterize the oxidative stress marker heterogeneity in order to study the effets of a suitable antioxidant supplementation on specific peripheral muscle markers in stable COPD patients.Through a comprehensive analysis integrating the oxidative stress complexity, this work showed that the main antioxidant deficits in stable COPD patients are on the vitamin C/E balance, zinc and selenium. Moreover, our results allowed to determine patient profiles characterized in particular by a women subgroup with an increased rate of lipid peroxides. Based on the main identified deficits and despite the large response heterogeneity, we have shown that antioxidant supplementation may optimize the benefits of a pulmonary rehabilitation program by improving especially muscle fiber strength, cross-sectional area (CSA) and maximal oxygen consumption of stable COPD patients. Thus, from the perspective of a phenotype approach, the use of CSA reference values, as established in our second study, appears to be a suitable biomarker but these should be optimized in order to be relevant in COPD patients.Finally, besides the benefits of using an antioxidant supplementation during pulmonary rehabilitation program, our results contribute to improve our knowledge about the role of oxidative stress in the pathophysiology of peripheral muscle impairment in COPD patients. Furthermore, a better understanding and characterization of heterogeneity of both oxidative stress and peripheral muscle impairment opens up promising research prospects with a view of adjusting the management of COPD patients.

Abstract The introduction of physiologically and therapeutically effective drugs in anaesthetic treatment has meant a significant change. Their discovery has thus contributed to a minimisation of their negative effects on a living organism. As a result, anaesthesiology has become more controllable and safer. These new drugs translate into more comfort for the patient in the course of anaesthesiology as well as his or her rapid recovery resulting in a shorter period of hospitalisation. The research of new physiologically and therapeutically effective substances is a pre-requisition of a potential higher standard of medical care. Older substances, e.g. Alkuronium and Gallamin, which, due to their undesirable effects, have come out of use, have lost their significance. Nowadays, these substances have been generally replaced by substances with an intermedial effect, e.g. Rokuronium and Cisatrakurium, which, compared with Alkuronium and Gallamin, show a minimum of undesirable effects. One of the foremost objectives of the current pharmaceutical research is to find a replacement of Sukcinylcholin, which, in spite of its known side effects, has had a non-substitutable position in urgent intubation. As a result, its use is limited to out-patient application and a certain selection of patient categories. Let us hope that we shall see a replacement of Sukcinylcholin being introduced in treatment in the near future. This would mean a final solution of problems arising from its side effects limiting its scope of application.

L’insuffisance cardiaque chronique est une maladie systémique où des dysfonctions périphériques viennent s’ajouter à l’incapacité du cœur à assurer un débit cardiaque adéquat aux tissus métabolisants. Parmi des dysfonctions périphériques, l’atrophie ainsi que la perte de force et d’endurance musculaire jouent un rôle primordial et contribuent largement à la genèse des symptômes majeurs de l’insuffisance cardiaque chronique, c’est à dire la fatigue, la dyspnée et l’intolérance à l’effort.<p>Ce n’est que depuis le début des années 1990 que des études ont montré que le réentraînement à l’effort pouvait être bénéfique pour le patient insuffisant cardiaque chronique; auparavant, il était considéré comme contre-indiqué.<p>La méthodologie d’entraînement proposée à cette époque aux patients était un entraînement de l’endurance cardio-vasculaire, le renforcement musculaire n’y avait pas sa place car on craignait que l’impact hémodynamique de ce type d’entraînement risquerait de détériorer la fonction cardiaque encore plus. Des études menées sur des contractions musculaires de type isométrique montraient en effet une diminution de la fonction cardiaque pendant l’entraînement. Cependant, les contraintes imposées pendant les exercices de renforcement musculaire dynamique (encore appelés « résistifs ») ne correspondent nullement à celles du renforcement isométrique. Des études sur des personnes saines ont montré que le renforcement musculaire est plus adapté à induire des améliorations du volume et de la force musculaire que l’entraînement de l’endurance cardio-vasculaire.<p>Le but de nos travaux a donc été de vérifier si l’introduction du renforcement musculaire, en complément de l’entraînement cardio-vasculaire ou bien comme entraînement à part entière, pouvait apporter un bénéfice supplémentaire chez l’insuffisant cardiaque chronique par son aptitude, du moins théorique, à mieux corriger certains aspects des dysfonctions musculaires.<p><p><p>Il s’agissait, dans les différentes études que nous avons menées, de vérifier qu’un entraînement composé de renforcement musculaire (au moins partiellement) chez le patient insuffisant cardiaque chronique:<p>-\ / Doctorat en Sciences de la motricité / info:eu-repo/semantics/nonPublished