23 resultados para Muscular function

em Reposit


Relevância:

70.00% 70.00%

Publicador:

Resumo:

As estatinas são utilizadas no tratamento das dislipidemias, com grande tolerância; no entanto, vários efeitos colaterais podem surgir, destacando-se miopatia. A prática regular do exercício físico (EF) produz modificações favoráveis no perfil lipídico; entretanto, pode gerar lesões musculares. OBJETIVO: Avaliar o efeito da associação entre exercício físico e estatinas na função muscular, pela análise histológica, em modelo experimental animal com dislipidemia. MÉTODOS: Foram utilizados 80 ratos machos Wistar, distribuídos em oito grupos, incluindo animais submetidos à dieta hipercolesterolêmica (DH), sinvastatina com (G1) e sem (G2) EF; DH e fluvastatina, com (G3) e sem EF (G4); alimentados com ração comercial (RC) na presença (G5) e ausência de (G6) EF; DH submetidos (G7) ou não (G8) a EF. A DH foi administrada por 90 dias, as estatinas e prática de EF em esteira rolante por oito semanas. Os animais foram sacrificados, e o músculo sóleo retirado para análise histológica. Aplicaram-se os testes t de Student pareado e análise multivariada, com nível significante para p < 0,05. RESULTADOS: As principais alterações histológicas encontradas foram fibras de diferentes diâmetros, atróficas, em degeneração, splitting, edema, infiltrado inflamatório. Essas alterações foram observadas em 90% dos animais do grupo G1, 80% do G2, 70% do G3, 30% do G4, 40% do G5 e 30% do G7. Nos grupos G6 e G8 identificaram-se fibras musculares com morfologia preservada. CONCLUSÕES: Na avaliação histológica muscular, a associação entre fluvastatina, sinvastatina e exercício físico acarreta alterações morfológicas com predomínio no uso da sinvastatina, variando de grau leve a grave, no músculo sóleo de ratos, induzidos pelos inibidores da HMG-CoA redutase.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Objective: To analyze the effect of arm bracing posture on respiratory muscle strength and pulmonary function in patients with Chronic Obstructive Pulmonary Disease (COPD).Methods: 20 patients with COPD (11 male; 67 +/- 8 years; BMI 24 +/- 3 Kg . m(-2)) were submitted to assessments of Maximal Inspiratory and Expiratory Pressures (MIP and MEP, respectively) and spirometry with and without arm bracing in a random order. The assessment with arm bracing was done on standing position and the height of the support was adjusted at the level of the ulnar styloid process with elbow flexion and trunk anterior inclination of 30 degrees promoting weight discharge in the upper limbs. Assessment without arm bracing was also performed on standing position, however with the arms relaxed alongside the body. The time interval between assessments was one week.Results: MIP, MEP and maximal voluntary ventilation (MW) were higher with arm bracing than without arm bracing (MIP 64 +/- 22 cmH(2)O versus 54 +/- 24 cmH(2)O, p = 0,00001; MEP 104 +/- 37 cmH(2)O versus 92 +/- 37 cmH(2)O, p = 0,00001 and MW 42 +/- 20 L/min versus 38 +/- 20 L/min, p = 0,003). Other variables did not show statistical significant difference.Conclusion: The arm bracing posture resulted in higher capacity to generate force and endurance of the respiratory muscles in patients with COPD. (C) 2009 Published by Elsevier Espana, S.L. on behalf of Sociedade Portuguesa de Pneumologia. All rights reserved.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The muscles can perform the same function in a specific segment (muscles of fast and slow contraction), and at the same time be antagonistic in relation to muscular action (flexors or extensors). The present research aimed to study the morphology, frequency and metabolism of fiber types and the contractile characteristics of extensor and flexors muscles of rabbit. We studied muscles anterior tibialis (AT), flexor digitorum supeficialis (FDS), extensor digitorum longus (EDL) and posterior tibialis (PT). The muscles were submitted to the techniques HE, NADH-TR and myofibrillar ATPase. In EDL and PT extensor muscles, the frequencies of red (SO + FOG) and white fibers (FG) were 68.77% and 31.23% versus 58.87% and 41.13%, respectively. In the AT and FDS flexor muscles, these frequencies were 75.14% and 24.86% versus 73.89% and 26.11%, respectively. In extensor muscles, the percentage of slow contraction fibers was 8.05% in EDL and 9.74% in PT, and in fast contraction, 91.95% in EDL and 90.26% in PT. In flexors, the slow contraction frequencies were 12.35% in AT and 8.17% in FDS, and in fast contraction, 87.65% and 91.83%, respectively. Skeletal muscles with antagonistic muscular actions (flexors and extensors) the morphological, contractile and metabolic characteristics are identical.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

OBJETIVO: Comparar a atividade muscular antes e após o contato com o solo entre as aterrissagens unilateral (AU) e bilateral (AB) em atletas do sexo masculino. PARTICIPANTES: Quinze atletas masculinos de voleibol sem sinais e sintomas de lesões nas extremidades inferiores (13 ± 1 ano, 1,70 ± 0,12m, 60 ± 12kg). MENSURAÇÕES:Os participantes realizaram dois saltos verticais, aterrissando unilateralmente e bilateralmente. A atividade mioelétrica do reto femoral (RF), bíceps femoral (BF), adutores de quadril (AQ) e a relação BF/RF foram comparados entre as duas aterrissagens e entre as fases caracterizadas por 100ms antes (PRE) e 100ms após (POS) o contato com o solo. RESULTADOS: Em ambas as aterrissagens, a ativação do RF foi maior na fase POS em relação à PRE. Na comparação entre as aterrissagens dentro da mesma fase não encontramos diferenças estatísticas. Apesar de o BF não ter apresentado diferenças entre as fases PRE e POS em cada aterrissagem, sua ativação foi maior na AU. Os AQ apresentaram maior ativação na fase POS durante a AU, no entanto não houve diferenças quando comparadas as duas aterrissagens. A relação BF/RF apresentou valores maiores em ambas as aterrissagens na fase PRE. No entanto, não encontramos diferenças entre as aterrissagens. CONCLUSÃO: Os resultados sugerem que cada músculo apresenta um papel diferente durante a fase de aterrissagem em homens. Enquanto que o RF possui como principal função a frenagem da articulação do joelho e do movimento descendente, caracterizada pelo aumento da ativação na fase pós-contato, o BF parece atenuar a tensão articular do joelho em atividades de maior impacto, mantendo-se mais ativo durante todo o ciclo da AU. Já a maior ativação dos AQ após o contato com solo na AU evidencia a importância da região lombo-pélvica na estabilização pélvica em situações de grande instabilidade. Estudos futuros são necessários para determinar os efeitos da ativação muscular apresentada na imposição de cargas mecânicas potencialmente lesivas no joelho em atletas do sexo masculino.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Purpose: To identify the electromyographic fatigue threshold in the erector spinae muscle. Methods: Eight 19 to 24-year-old male volunteers participated in this study, in which surface electrodes were used, as well as a biological signals acquisition module (Lynx) with a sampling frequency of 1000Hz, a 1000 times gain, a 20Hz high pass filter and a 500Hz low pass filter. The test consisted of repeated isometric contractions of the erector spinae muscle in a 45° hip flexion posture, with 30%, 40%, 50% and 60% of the maximum voluntary isometric contraction. Results: A positive correlation of the RMS (root mean square) value as a function of time was found for most of the subjects with 40% (N = 6), 50% (N = 7) and 60% (N = 8) loads of the maximum voluntary isometric contraction. Conclusions: It was concluded, from this study, that the proposed protocol provides evidence, through the electromyographic signal, of the development of fatigue in the erector spinae muscle with loads of 40%, 50% and 60% of the maximum voluntary isometric contraction. The protocol also allows the electromyographic fatigue threshold and its probable applicability in the diagnosis of this phenomenon during repetitive activities to be determined.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The muscular dystrophy of Golden Retriever is a degenerative miopaty caused by the absence of dystrophy and it is genetically homologue of the Duchenne muscular dystrophy in humans, so, these dogs are considerably experimental models for studies on cellular therapy. Their successful depends of the adequate immunosuppression. Cyclosporin A is indicated for that and the monitoring of blood concentration and adverse effects are essential to viabilise the therapy. It was studied GRMD dogs, and normal dogs from the same breed, submitted for therapy with CsA, associated, on GRMD, of cell transplantation. It was evaluated the possible effects of the drug on renal functions. It has been considerate the clinic manifestations, urinalisis, testis of glomerular function and blood concentrations of urea, cretinine, sodium and potassium. In our results we found a discrete increase of blood urea on booth groups; increased levels of urine's cylinders and protein and also increase of urinary density on GRMD group. CsA therapy could make acute lesions on renal tubules, especially on GRMD. These dogs also have different reactions than normal dogs on relation of ions homeostasis and renal function. However, earlier diagnosis and adequate treatment could prevent the development of renal diseases.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

CONTEXT AND OBJECTIVE: There is uncertainty in the literature regarding the theory that obstetric events and pelvic floor injuries give rise to lower risk of subsequent urinary incontinence among women delivering via cesarean section than among women delivering vaginally. The objective of this study was to assess the two-year postpartum prevalence of urinary incontinence and pelvic floor muscle dysfunction and the factors responsible for them. DESIGN AND SETTING: Cross-sectional study, conducted in a public university. METHODS: 220 women who had undergone elective cesarean section or vaginal childbirth two years earlier were selected. Their urinary incontinence symptoms were investigated, and their pelvic floor muscle dysfunction was assessed using digital palpation and a perineometer. RESULTS: The two-year urinary incontinence prevalences following vaginal childbirth and cesarean section were 17% and 18.9%, respectively. The only risk factor for pelvic floor muscle dysfunction was weight gain during pregnancy. Body mass index less than 25 kg/m2 and normal pelvic floor muscle function protected against urinary incontinence. Gestational urinary incontinence increased the risk of two-year postpartum urinary incontinence. CONCLUSION: Gestational urinary incontinence was a crucial precursor of postpartum urinary incontinence. Weight gain during pregnancy increased the subsequent risk of pelvic floor muscle dysfunction, and elective cesarean section did not prevent urinary incontinence.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)