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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.
191

Respostas motoras durante a marcha com suporte de peso corporal na esteira em diferentes velocidades em indivíduos com lesão medular / Motor responses during body weight support treadmill gait at different speeds in individuals with spinal cord injury

Padula, Natalia 14 March 2018 (has links)
A Lesão Medular (LM) afeta a funcionalidade do indivíduo e pode reduzir drasticamente a independência. A restauração da mobilidade e do andar, é uma das principais metas das intervenções na população com LM, e nesse contexto o treinamento locomotor (TLSP) é uma intervenção utilizada com objetivo de fornecer estímulos sensoriais específicos ao sistema nervoso danificado para estimular as redes e circuitos preservados da medula. A velocidade é uma aferência sensorial importante durante o TLSP em esteira. Objetivo: investigar o efeito da variação de velocidade sobre as respostas motoras de indivíduos com lesões medulares durante TLSP em esteira. Método: 20 sujeitos sem LM denominado de grupo controle (GC) e 13 com LM completa (GLM) foram submetidos ao protocolo TLSP em esteira nas velocidades 2, 3 e 4 km/h. Foi realizada uma análise de EMG para avaliar atividade muscular de vasto lateral (VL), bíceps femural (BF), tibial anterior (TA) e gastrocnêmio lateral (GL) ao longo do ciclo do passo. Resultados: O GC apresentou maior atividade muscular distal TA e GL quando comparado ao GLM com maior atividade proximal VL e BF durante todas as fases da marcha. A velocidade que apresentou maior atividade muscular foi a intermediária (3km/h), quando comparado as velocidades 2Km/h e 4km/h. O aumento da velocidade resultou em maior influência nos músculos distais. Conclusão: a velocidade pode influenciar nas respostas motoras locomotoras de indivíduos com LM. O aumento da velocidade teve um papel importante no aumento da atividade muscular, contudo a atividade muscular foi maior na velocidade intermediária (3km/h) / Spinal Cord Injury (SCI) affects the individual\'s functionality and can gradually reduce independence. The restoration of mobility and walking, is one of the main goals of the interventions in SCI population. In this context body weight support treadmill training (BWSTT) is an intervention used to provide specific sensory stimuli to the damaged nervous system to stimulate the networks and circuits preserved in the spinal cord. Velocity is an important sensory afferment during the BWSTT. Objective: to investigate the effect of speed variation on motor responses of use with spinal cord injuries BWSTTl. Method: 20 healthy subjects composed the control group (CG) and 13 with complete SCI (SCIG) were submitted to BWSTT at speeds 2, 3 and 4 km/h. An EMG analysis was performed to evaluate the muscle activity of lateral vastus (LV), biceps femorales (BF), tibial anterior (TA) and gastrocnemius lateral (GL) throughout the cycle of the step. Results: The CG had greater distal muscle activity TA and GL when compared to GLM with greater proximal activity, VL and BF, during all gait phases. The velocity that presented greater muscular activity was the intermediate (3km/h), when compared as speeds 2Km/h and 4km/h. Increased speed resulted in greater influence on the distal muscles. Conclusion: the velocity can influence motor responses. Increased speed had an important role in increasing muscle activity, however, muscle activity was greater at intermediate velocity (3km / h)
192

Influência do treinamento de força sobre a estratégia de prova e o desempenho de corredores de longa distância em um teste contrarrelógio de 10 km / Influence of strength training on pacing strategy and performance in long distance runners in a 10-km running time trial

Mayara Vieira Damasceno 16 October 2015 (has links)
O objetivo do presente estudo foi analisar o impacto de oito semanas de um programa de treinamento de força sobre a estratégia de prova e o desempenho de corredores de longa distância durante uma prova contrarrelógio de 10 km. Antes e após a fase de intervenção com o programa de treinamento de força, dezoito corredores recreacionais divididos nos grupos treinamento (GT) (n = 9) e controle (GC) (n = 9) foram submetidos aos seguintes testes: a) antropometria e teste progressivo até a exaustão voluntária, b) teste com velocidade submáxima constante, c) simulação de uma prova de 10 km para análise da estratégia de prova, d) teste de drop jump, e) teste de wingate, f) teste de uma repetição máxima (1RM) e g) teste de tempo limite. A atividade eletromiográfica dos músculos vasto medial e bíceps femoral foi medida durante o teste de 1RM. No GT, a magnitude de melhora para o 1RM (23,0 ± 4,2%, P = 0,001), drop jump (12,7 ± 4,6%, P = 0,039), e velocidade de pico na esteira (2,9 ± 0,8%, P = 0,013) foi significativamente maior em relação ao GC. Este aumento do 1RM para o GT foi acompanhado por uma tendência a uma maior atividade eletromiográfica (P = 0,080). A magnitude de melhora no desempenho na prova de 10 km foi maior (2,5%) no GT que no GC (-0,7%, P = 0,039). O desempenho foi melhorado principalmente devido a velocidades mais elevadas durante as últimas sete voltas (últimos 2800 m) da prova de 10 km. No entanto, não houve diferenças significativas antes e após o período de treinamento para o padrão de estratégia de prova utilizada, consumo máximo de oxigênio, ponto de compensação respiratória, economia de corrida e desempenho anaeróbio para ambos os grupos (P > 0,05). Em conclusão, estes resultados sugerem que, embora um programa de treinamento de força não altere a estratégia de prova adotada, ele oferece um potente estímulo para combater a fadiga durante as últimas partes de uma corrida de 10 km, resultando em um melhor desempenho total / The aim of the present study was to analyze the impact of an 8-week strength-training program on performance and pacing strategy adopted by runners during a self-paced endurance running. Eighteen endurance runners were allocated into either strength training group (STG, n = 9) or control group (CG, n = 9) and performed the following tests before and after the training period: a) anthropometric measures and maximal incremental treadmill test, b) running speed-constant test, c) 10-km running time trial, d) drop jump test, e) 30-s Wingate anaerobic test, f) maximum dynamic strength test (1RM), g) time to exhaustion test. Electromyographic activity of vastus medialis and biceps femoris was measured during 1RM test. In the STG, the magnitude of improvement for 1RM (23.0 ± 4.2%, P = 0.001), drop jump (12.7 ± 4.6%, P = 0.039), and peak treadmill speed (2.9 ± 0.8%, P = 0.013) was significantly higher compared to CG. This increase in the 1RM for STG was accompanied by a tendency to a higher electromyographic activity (P = 0.080). The magnitude of improvement for 10-km running performance was higher (2.5%) for STG than for CG (-0.7%, P = 0.039). Performance was improved mainly due higher speeds during the last seven laps (last 2800 m) of the 10-km running. Nevertheless, there were no significant differences between before and after training period for pacing strategy, maximal oxygen uptake, respiratory compensation point, running economy, and anaerobic performance for both groups (P > 0.05). In conclusion, these findings suggest that, although a strength-training program does not alter the pacing strategy, it offers a potent stimulus to counteract fatigue during the last parts of a 10-km running, resulting in an improved overall running performance
193

Treinamento e overtraining induziram alterações comportamentais e bioquímicas em ratos Wistar / Training and overtraining induced behavioral and biochemical changes in Wistar rats

Moranza, Henriette Gellert [UNESP] 22 February 2017 (has links)
Submitted by Henriette Gellert Moranza null (henriette.moranza@hotmail.com) on 2017-03-14T00:20:55Z No. of bitstreams: 1 Dissertação Henriette Moranza.pdf: 1760193 bytes, checksum: 2f7508b39b048f746c69e728ec197fa7 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-03-20T18:56:34Z (GMT) No. of bitstreams: 1 moranza_hg_me_jabo.pdf: 1760193 bytes, checksum: 2f7508b39b048f746c69e728ec197fa7 (MD5) / Made available in DSpace on 2017-03-20T18:56:34Z (GMT). No. of bitstreams: 1 moranza_hg_me_jabo.pdf: 1760193 bytes, checksum: 2f7508b39b048f746c69e728ec197fa7 (MD5) Previous issue date: 2017-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivo: investigar o comportamento, concentrações de corticosterona, lactato e glicose de ratos Wistar submetidos a um protocolo de "overtraining" (PO) para o desenvolvimento de "Functional" (FOR) ou "Nonfunctional Overreaching" (NFOR). Métodos: inicialmente a amostragem de indivíduos foi de 49. O grupo controle (C, n= 16) realizou um programa de condicionamento leve (1 sessão/dia/ 2x/sem./12 m.min-1). Os outros ratos (n= 33) foram submetidos ao PO, com duração de 12 sem., prescrito para produzir um desequilíbrio entre as sessões de exercício e o período de recuperação. Em 8 sem. foram realizadas sessões de treino diárias, por 5 d consecutivos seguidas por 2 d de recuperação. Nas 4 sem. subsequentes, houve aumento da frequência de treino (2, 3, 4 e 4 x/d) e redução do tempo de recuperação entre as sessões (4, 3, 2 e 2 h). Para avaliação da aptidão física, os ratos foram submetidos a sete testes de esforço máximo (T-máx) durante e dois testes após o PO. Dois grupos foram identificados pela diferença da inclinação (α) obtida a partir da regressão linear dos desempenhos individuais nos Tmáx-3, 4, 5, 6 e 7. Ratos NFOR (n= 14) tiveram α= < -0.98. Analisou-se a recuperação passiva de 2 sem., sendo realizado testes de Campo Aberto (CA) e Labirinto em Cruz Elevado (LCE). Neste período, dois Tmáxs (8 e 9) foram realizados para verificação da continuidade das condições FOR e NFOR. Em Tmáx-2, Tmáx-6 e Tmáx-9 realizaram-se coletas sanguíneas para quantificação das concentrações plasmáticas de lactato ([lac]antes e [lac]após) e glicose ([glic]antes e [glic]após). Quantificou-se corticosterona durante o repouso e após os Tmáx-7 e 9, ([cort]repouso e [cort]após). Glândulas adrenais foram coletadas e pesadas. Para análise estatística aplicaram-se ANOVA de uma via e para medidas repetidas no tempo, testes t de Student pareado e não pareado e foi realizada correlação de Pearson (P< 0.05). Resultados: FOR e NFOR tiveram aumento de desempenho a partir do Tmáx-2 (303.8±13.8; 294.3±18.9 e 190.2±12.2 kg.m, respectivamente). O grupo NFOR teve o desempenho reduzido no Tmáx-7 (292.2±36.4 kg.m). No teste CA, ocorreu aumento da frequência de levantar para os grupos FOR e NFOR em relação ao grupo C. Houve redução da [lac]após para FOR e NFOR no Tmáx-6 em relação ao grupo C (3.61±0.38; 5.43±0.63; 7.64±0.43 mmol/L, respectivamente) sendo que NFOR obteve lactatemia maior que FOR. Ainda no Tmáx-6, a [glic]após foi menor em FOR em relação ao grupo C (5.66±0.17 vs. 6.52±0.21). Não houve diferença para as concentrações de corticosterona. Houve aumento do índice adrenosomático para o grupo NFOR no Tmáx-7 e redução deste após o Tmáx-9. Conclusões: "functional" ou "nonfunctional overreaching" provocou ansiedade e alterações nas concentrações de lactato e glicose em ambos os grupos bem como aumento do índice adrenosomático nos ratos que demonstraram a condição NFOR. / Purpose: To investigate the behavior, corticosterone and lactate concentrations of Wistar rats submitted to an overtraining protocol (OP) for the development of functional (FOR) or nonfunctional overreaching (NFOR). Methods: Sampling of rats was 49. The control group (C, n= 16) performed a mild conditioning program (1 session/day / 2x/wk/12 m.min-1). The other rats, n= 33, were submitted to 12-week OP prescribed to produce an imbalance between the exercise sessions and the recovery period. In 8 wks. daily training sessions were performed for 5 consecutive d followed by 2 d of recovery. In the following 4 wks. (2, 3, 4 and 4 x / d) there was an increase in training frequency and reduction of recovery time between sessions (4, 3, 2 and 2 h). To evaluate physical fitness, the rats were submitted to seven maximum tests (Tmax) during and two tests after the PO. Two groups were identified by the slope difference (α) obtained from the linear regression of individual performances at Tmax-3, 4, 5, 6 and 7. NFOR rats (n= 14) had α = -0.98. Passive recovery of 2 wks was analyzed, and Open Field (OF) and Elevated Plus Maze (EPM) tests were performed. In this period, 2 Tmaxs (8 and 9) were performed to verify the continuity of FOR and NFOR conditions. Blood samples were collected for Tmax-2, Tmax-6 and Tmax-9 for the quantification of plasma lactate concentrations ([lac]before and [lac]after) and glucose ([glic]before and [glic]after). Corticosterone was measured at rest and after Tmax-7 and 9, ([cort]rest and [cort]after). Adrenal glands were collected and weighed. For statistical analysis one-way ANOVA and repeated measures ANOVA, paired and unpaired Student's t-tests and a Pearson correlation were performed (P < 0.05). Results: NFOR and FOR had an increase in performance from Tmax-2 (303.8±13.8, 294.3±18.9 and 190.2±12.2 kg.m, respectively). The NFOR group had reduced performance in Tmax-7 (292.2±36.4 kg.m). In the OF test, there was an increase in the frequency of rearing for the FOR and NFOR groups in relation to the C group. There was reduction of [lac]after for FOR and NFOR in Tmax-6 compared to group C (3.61±0.38, 5.43±0.63 , 7.64 ± 0.43 mmol/L, respectively) and NFOR obtained lactate concentrations greater than FOR. Still in Tmax-6, [glic]after was lower in FOR compared to group C (5.66±0.17 vs. 6.52±0.21). In Tmax-7, resting was lower for the NFOR group compared to C. There was no difference in corticosterone concentrations. There was an increase in the adrenosomatic index for the NFOR group in the Tmax-7 and a reduction in the latter after the Tmax-9. Conclusion: functional and nonfunctional overreaching caused anxiety and changes in lactate and glucose concentrations in both groups as well as increase in the adrenosomatic index in rats that demonstrated the NFOR condition.
194

Influência do treinamento de força sobre a estratégia de prova e o desempenho de corredores de longa distância em um teste contrarrelógio de 10 km / Influence of strength training on pacing strategy and performance in long distance runners in a 10-km running time trial

Damasceno, Mayara Vieira 16 October 2015 (has links)
O objetivo do presente estudo foi analisar o impacto de oito semanas de um programa de treinamento de força sobre a estratégia de prova e o desempenho de corredores de longa distância durante uma prova contrarrelógio de 10 km. Antes e após a fase de intervenção com o programa de treinamento de força, dezoito corredores recreacionais divididos nos grupos treinamento (GT) (n = 9) e controle (GC) (n = 9) foram submetidos aos seguintes testes: a) antropometria e teste progressivo até a exaustão voluntária, b) teste com velocidade submáxima constante, c) simulação de uma prova de 10 km para análise da estratégia de prova, d) teste de drop jump, e) teste de wingate, f) teste de uma repetição máxima (1RM) e g) teste de tempo limite. A atividade eletromiográfica dos músculos vasto medial e bíceps femoral foi medida durante o teste de 1RM. No GT, a magnitude de melhora para o 1RM (23,0 ± 4,2%, P = 0,001), drop jump (12,7 ± 4,6%, P = 0,039), e velocidade de pico na esteira (2,9 ± 0,8%, P = 0,013) foi significativamente maior em relação ao GC. Este aumento do 1RM para o GT foi acompanhado por uma tendência a uma maior atividade eletromiográfica (P = 0,080). A magnitude de melhora no desempenho na prova de 10 km foi maior (2,5%) no GT que no GC (-0,7%, P = 0,039). O desempenho foi melhorado principalmente devido a velocidades mais elevadas durante as últimas sete voltas (últimos 2800 m) da prova de 10 km. No entanto, não houve diferenças significativas antes e após o período de treinamento para o padrão de estratégia de prova utilizada, consumo máximo de oxigênio, ponto de compensação respiratória, economia de corrida e desempenho anaeróbio para ambos os grupos (P > 0,05). Em conclusão, estes resultados sugerem que, embora um programa de treinamento de força não altere a estratégia de prova adotada, ele oferece um potente estímulo para combater a fadiga durante as últimas partes de uma corrida de 10 km, resultando em um melhor desempenho total / The aim of the present study was to analyze the impact of an 8-week strength-training program on performance and pacing strategy adopted by runners during a self-paced endurance running. Eighteen endurance runners were allocated into either strength training group (STG, n = 9) or control group (CG, n = 9) and performed the following tests before and after the training period: a) anthropometric measures and maximal incremental treadmill test, b) running speed-constant test, c) 10-km running time trial, d) drop jump test, e) 30-s Wingate anaerobic test, f) maximum dynamic strength test (1RM), g) time to exhaustion test. Electromyographic activity of vastus medialis and biceps femoris was measured during 1RM test. In the STG, the magnitude of improvement for 1RM (23.0 ± 4.2%, P = 0.001), drop jump (12.7 ± 4.6%, P = 0.039), and peak treadmill speed (2.9 ± 0.8%, P = 0.013) was significantly higher compared to CG. This increase in the 1RM for STG was accompanied by a tendency to a higher electromyographic activity (P = 0.080). The magnitude of improvement for 10-km running performance was higher (2.5%) for STG than for CG (-0.7%, P = 0.039). Performance was improved mainly due higher speeds during the last seven laps (last 2800 m) of the 10-km running. Nevertheless, there were no significant differences between before and after training period for pacing strategy, maximal oxygen uptake, respiratory compensation point, running economy, and anaerobic performance for both groups (P > 0.05). In conclusion, these findings suggest that, although a strength-training program does not alter the pacing strategy, it offers a potent stimulus to counteract fatigue during the last parts of a 10-km running, resulting in an improved overall running performance
195

Comparison of oxygen consumption while walking on treadmill wearing MBT Shoes versus Orthopedic Shoes : A treatise on shoe mass

Thuesen, Anna Helena, Lindahl, Benjamin January 2009 (has links)
Purpose: The purpose of this study was to investigate if there was any difference in energy expenditure (kcal/min) and oxygen consumption (VO2) between subjects walking with Masai Barefoot Technology ® (MBT) shoes and regular orthopedic shoes. The research hypothesis was that MBT shoes demand more energy expenditure than regular orthopedic shoes. Methods: Seven women aged 49-65 were recruited for the study. The subjects were tested in two sessions, with a minimum of two weeks in between each sesssion. On each test session the subjects walked with both MBT shoes and orthopedic shoes which were adjusted in mass (g) to match the mass of the MBT shoes. While the subjects walked on a treadmill, the oxygen consumption (VO2), heart rate (min-1) and self selected velocity (m/s) for each of the shoe types was measured. Results: Results showed that there is no significant difference in oxygen consumption (VO2) between the MBT and orthopedic shoes. Energy expenditure (kcal/min) was also calculated from the data and the results revealed that there is no significant differ-ence between MBT and orthopedic shoes in energy expenditure (kcal/min) either. The self selected velocity (m/s) between the two shoe types was also found to be insignificant. Conclusion: The results showed no significant difference between the shoes. This could indicate that the specific construction of the MBT shoe has no effect on the energy expenditure (kcal/min) of its user. This lack of difference may be due to the equal mass of the shoes, but since oxygen consumption (VO2) was not investigated in orthopedic shoes with different shoe masses, this conclusion cannot be confirmed. The self selected velocity (m/s) was found to be insignificant and this finding could suggest to that prolonged usage of the MBT shoe may diminish gait parameters dissimilarities during ambulation. This study should therefore be seen as a pilot study and further investigation in this area should be pursued.
196

Gait and Working Memory in Alzheimer’s Disease, Aging and Small Vessel Cerebrovascular Disease

Nadkarni, Neelesh 19 February 2010 (has links)
This thesis first explored the effects of concurrent spatial attention and working memory task performance on over-ground gait in healthy young and older adults. It then compared over-ground gait parameters and working memory performance in mild Alzheimer’s Disease (AD) and normal controls (NC) and investigated costs of dual-tasking on working memory performance and cadence during treadmill walking at preferred walking speed in the two groups. Furthermore, it explored these differences in AD and NC groups in relation to their subcortical hyperintensities (SH) that were rated using standardized scales on MRI. Reaction times and accuracy on working memory performance measures were collected under single and dual task conditions. Over-ground gait parameters were measured on an automated walkway. Costs of dual-tasking on gait parameters and working memory performance were measured at a constant velocity on a treadmill. The hypotheses that working memory influences gait performance and that a higher SH burden negatively influences over-ground gait and costs of dual-task conditions, were supported in a series of experiments. Gait slowed down while performing working memory and spatial attention tasks in young and older adults. Patients with mild AD, compared to NC, had a slower gait velocity, shorter stride length and lower cadence on the walkway. When the two groups were subdivided into higher and lower SH groups based on their median SH score, the NC group with lower SH burden walked significantly faster with a higher cadence and a longer stride length than the other three groups. Lastly, a higher SH burden negatively influenced working memory performance in NC while in mild AD patients, it had negative influences on adaptive changes in gait while dual-tasking. These results suggest that, in dual-task condition, SH interfere with processing speed in NC and on gait in AD. These findings provide new insights in to tradeoffs during dual tasking in relation to cerebrovascular disease. This has ecological implications because of the prevalence of small vessel disease in aging and dementia, may impact on predicting falls in AD.
197

Gait and Working Memory in Alzheimer’s Disease, Aging and Small Vessel Cerebrovascular Disease

Nadkarni, Neelesh 19 February 2010 (has links)
This thesis first explored the effects of concurrent spatial attention and working memory task performance on over-ground gait in healthy young and older adults. It then compared over-ground gait parameters and working memory performance in mild Alzheimer’s Disease (AD) and normal controls (NC) and investigated costs of dual-tasking on working memory performance and cadence during treadmill walking at preferred walking speed in the two groups. Furthermore, it explored these differences in AD and NC groups in relation to their subcortical hyperintensities (SH) that were rated using standardized scales on MRI. Reaction times and accuracy on working memory performance measures were collected under single and dual task conditions. Over-ground gait parameters were measured on an automated walkway. Costs of dual-tasking on gait parameters and working memory performance were measured at a constant velocity on a treadmill. The hypotheses that working memory influences gait performance and that a higher SH burden negatively influences over-ground gait and costs of dual-task conditions, were supported in a series of experiments. Gait slowed down while performing working memory and spatial attention tasks in young and older adults. Patients with mild AD, compared to NC, had a slower gait velocity, shorter stride length and lower cadence on the walkway. When the two groups were subdivided into higher and lower SH groups based on their median SH score, the NC group with lower SH burden walked significantly faster with a higher cadence and a longer stride length than the other three groups. Lastly, a higher SH burden negatively influenced working memory performance in NC while in mild AD patients, it had negative influences on adaptive changes in gait while dual-tasking. These results suggest that, in dual-task condition, SH interfere with processing speed in NC and on gait in AD. These findings provide new insights in to tradeoffs during dual tasking in relation to cerebrovascular disease. This has ecological implications because of the prevalence of small vessel disease in aging and dementia, may impact on predicting falls in AD.
198

Reabilitação e plasticidade neuromuscular após lesão medular : efeitos do treino de marcha em esteira e transplante de glia embainhante olfatória / Rehabilitation and neuromuscular plasticity after spinal cord injury: effects of treadmill step training and olfactory ensheathing glia transplantation

Ilha, Jocemar January 2011 (has links)
O objetivo desta Tese foi analisar os efeitos do treino de marcha isolado e em combinação com transplante de glia embainhante olfatória (GEO) na recuperação funcional e na plasticidade neuromuscular dependente da atividade em um modelo experimental de paraplegia. Para tanto, foram realizados 2 experimentos. No 1º experimento foi realizada completa transecção da medula espinal (TME) em ratos Wistar adultos e após 5 dias iniciou-se um protocolo de 9 semanas de treino de marcha em esteira com suporte de peso corporal. No 2º experimento, os animais receberam, imediatamente após a TME, transplante de células gliais embainhantes olfatórias (GEO) e, como no primeiro experimento, iniciaram o treino de marcha 5 dias após a lesão/transplante. Durante o período dos experimentos, estudos comportamentais para acompanhamento da recuperação da função sensório-motora dos animais foram periodicamente realizados. Além disso, ao término da fase de treinamento (10 semanas após a lesão/transplante), análises histológicas e bioquímicas foram realizadas em amostras de tecido retiradas da medula espinal e músculo sóleo. Os resultados mostram que o treino de marcha em esteira promove melhora da função sensório-motora nos membros posteriores (MPs) de ratos com completa transecção da medula espinal (TME). Os animais treinados apresentaram escores mais altos na escala BBB e normalização do reflexo flexor de retirada. Além disso, os animais com TME apresentaram atrofia do soma celular nos motoneurônios alfa, redução na expressão de sinaptofisina e na atividade da Na+,K+-ATPase na região lombar. Os animais treinados mostraram soma motoneuronal, expressão de sinaptofisina e atividade da bomba de Na+,K+-ATPase similares aos controles. No músculo sóleo, a TME causou severa atrofia muscular, que foi acompanhada pela redução na expressão do fator neurotrófico derivado do encéfalo (BDNF) neste músculo. Por outro lado, o treino de marcha foi capaz de parcialmente impedir/reverter a atrofia provocada pela paralisia muscular e promover um significante aumento na expressão do BDNF, o qual teve positiva correlação com o trofismo muscular dependente da atividade motora no músculo sóleo. O transplante de glia embainhante olfatória (GEO) promoveu significativo aumento nos escores da escala BBB nos animais com completa TME. Entretanto, o treino de marcha foi capaz de acelerar este ganho funcional. Apesar de não ser observada significativa regeneração axonal através do local da lesão, sugerindo que as melhoras funcionais ocorreram independentemente da existência de regeneração axonal. Estes resultados sugerem que o treino de marcha após a TME promove plasticidade morfológica e bioquímica dependente da atividade nos tecidos neuromusculares. A melhora funcional ocorreu concomitantemente a estas alterações plásticas. Além disso, a terapia de transplante de GEO mostrou resultados positivos na recuperação da função motora dos MPs que foi acelerada pelo treino de marcha, mesmo na ausência de regeneração axonal através da lesão. Estes dados mostram importantes informações neurobiológicas que fornecem base neurocientífica para o uso seguro e eficaz destas terapias na reabilitação após LME. / The aim of this thesis was to study the effects of treadmill step training alone and in combination with olfactory ensheathing cells (OEC) on functional recovery and activity-dependent neuromuscular plasticity in a traumatic paraplegia model. For this, we made two experiments. In the 1st experiment, complete spinal cord transection (SCT) was made in adult Wistar rats and after 5 days the spinal animals were underwent a 9 week body-weight-supported treadmill training (BWSTT) program. In the 2nd experiment, the spinal animals received acute olfactory ensheathing cell (OEC) transplantation and, similar to the 1st experiment, started a BWSTT 5 days after the injury/transplantation. Behavioral tests were periodically performed in order to study the hindlimb sensorimotor functions in both experiments. Furthermore, after 9 weeks of the training (10 weeks after SCI/transplantation), histological and biochemical analysis were performed in spinal cord and soleus muscle tissues. The results show that treadmill step training improves hindlimb sensorimotor function in rats with complete spinal cord transection (SCT). The trained animals showed higher BBB scores and normalization of the withdrawal reflex. Furthermore, spinal animals showed alpha motoneuron soma size atrophy, decrease in synaptophysin expression and Na+,K+-ATPase activity in lumbar spinal cord. Trained SCT animals showed motoneuron soma size, synaptophysin expression and Na+,K+-ATPase activity values similar to controls. In soleus muscle, SCT led to severe muscular atrophy, which was accompanied by a decrease in brain-derived neurotrophic factor (BDNF) expression in this muscle. On the other hand, treadmill step training was able to revert/prevent this paralysis-induced muscular atrophy and promote significant improvement in soleus BDNF expression, which was positively correlated to activity-dependent muscular trophism. Olfactory ensheathing cell (OEC) transplantation promotes significant improvements in the BBB scores of animals with SCT. However, treadmill step training was able to accelerate this functional gain. There was no significant axonal regeneration that traversed the injury site, which suggests that functional gains occurred in a manner independent of axonal regeneration. Taken as a whole, these results suggest that treadmill step training after SCT promotes activity-dependent morphological and biochemical plasticity in neuromuscular tissues. The functional improvements occurred concomitantly to these plastic changes. Moreover, OEC therapy showed positive results on hindlimb motor function recovery which was accelerated with treadmill step training even in the absence of axonal regeneration across the lesion site. These results represent important neurobiological information for the neuroscientific basis that supports these therapies as an efficient and safe approach in spinal cord injury rehabilitation.
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Efeitos do exercício físico sobre a expressão da proteína glial fibrilar ácida (GFAP) e comportamento motor de ratos submetidos ao modelo de doença de Parkinson induzida por 6-OHDA / Exercise improves motor behavioral deficits and induces GFAP expression in 6-OHDA model of Parkinson’s disease

Dutra, Márcio Ferreira January 2009 (has links)
The aim of this study was to investigate whether exercise could improve motor behavioral deficits and alter expression of glial fibrillary acidic protein (GFAP) in dorsal striatum in a 6-hydroxydopamine (6-OHDA) rat model of Parkinson’s disease (PD). To this end, animals were randomly divided into 4 groups: sham sedentary (SS, n = 7); sham trained (ST, n=8); lesioned sedentary (LS, n=8) and lesioned trained (LT, n = 8). Rats were unilaterally lesioned with 6-OHDA (10 μg/3 μg) injected into the left medial forebrain bundle and sham groups were only injected with vehicle solution. The treadmill training protocol consisted of running with progressive increase in velocity, 5 days/week, during 4 weeks. Behavioral tasks were applied to asses the motor abilities of all animals prior to 6-OHDA injection and at 8th and 29th days post-injection. The tyrosine hydroxylase (TH - in substantia nigra pars compacta) and GFAP (in dorsal striatum) immunostaining was evaluated by semiquantitative analysis of the intensity (optical density - OD). The 6-OHDA lesion decreased the OD of TH and increased the OD of GFAP. In addition, the 6-OHDA lesion increased the number of ipsilateral rotations induced by methylphenidate (40 mg/kg, i.p., 30 min) and caused motor behavioral deficits. On the other hand, the treadmill training resulted in an increase in maximal exercise capacity in both trained groups (ST and LT). The training was able to reduce the number of ipsilateral rotations and ameliorated the motor behavioral deficits on 8th and 29th days postlesion. Interestingly, the exercise led to a significant increase in OD of GFAP in the LT group while there was no such effect in ST group. Our results indicate that treadmill training can improve motor behavioral deficits and suggest that the effects of exercise may be directly or, indirectly, mediated by astrocytes, as an increase in GFAP was observed in the dorsal striatum. Nevertheless, these are the first data showing an increase in GFAP expression post-exercise in this model and further research is needed to determine the precise action of exercise on astrocytes in Parkinson’s disease.
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Caracterização da coordenação dos membros inferiores e avaliação dos efeitos de um treino da marcha em esteira com aumento de carga em sujeitos com doença de Parkinson

Filippin, Nadiesca Taisa 11 December 2009 (has links)
Made available in DSpace on 2016-06-02T20:18:11Z (GMT). No. of bitstreams: 1 2719.pdf: 1232540 bytes, checksum: c1a6fcc405feb23c0e04aefc524c6285 (MD5) Previous issue date: 2009-12-11 / Financiadora de Estudos e Projetos / The influence of the Parkinson s disease (DP) on lower limbs coordination during walking is still not completely known. The intra and interlimb coordination are essential during walking and an impairment in the motor control may affect them. On the other hand, studies about the effects of walking training with additional body load in PD are lacking. There is evidence that the increase of body load during treadmill walking improves reflex activity and leg extensor muscle activity, which are impaired in subjects with PD. Furthermore, the PD affects the quality of life of the subjects. For these reasons, two studies were accomplished. The purpose of the Study I was to compare the intralimb and interlimb coordination during walking between subjects with PD and healthy control subjects. Ten subjects with PD (PG) and ten control subjects (CG) were submitted to a clinical evaluation and a gait kinematic evaluation. The PG presented larger stride duration, stance and swing phase durations and smaller stride length, speed, cadence and joint range of motion than CG. The intra and interlimb coordination do not differ significantly between groups. These results indicate that the PG presented spatial-temporal variables and joint range of motion alterations but it was able to adapt to the limitations imposed by the disease and accomplish a functional gait, without undermine the intra and interlimb coordination pattern. The purpose of the Study II was to assess the effects of treadmill walking training with additional body load on the quality of life, motor functions and gait of subjects with PD. Nine subjects with idiopathic PD, in moderate stage, participed in this study. The training program was divided into three phases: treadmill training with additional body load (A1), control condition (conventional physical therapy group) (B) and treadmill training with load again (A2). Each phase lasted six weeks. Both evaluations and training were performed during on-phase of the medication cycle. The results showed an improvement in total score, and mobility, activities of daily life and cognition subscores related to quality of life and an improvement in the motor functions. Significant increase in propulsive forces, stride length, speed, and maximum hip extension during stance were also observed after the training program. In conclusion, the treadmill training with additional body load promoted an improvement in different aspects related to quality of life and in important variables for the maintenance of the functional gait of subjects with PD, and it is a promising alternative to optimize the rehabilitation process in combination with conventional physical therapy. / A influência da doença de Parkinson (DP) sobre a coordenação dos membros inferiores durante a marcha ainda não é bem compreendida. As coordenações intra e intermembros são fundamentais durante a marcha e podem sofrer modificações caso ocorra algum distúrbio no controle do movimento. Por outro lado, estudos sobre os efeitos do treino da marcha com aumento da carga corporal na DP são escassos. Há evidências que o acréscimo de carga durante o treino em esteira melhora a atividade reflexa e a atividade dos músculos extensores da perna, os quais estão prejudicados em sujeitos com DP. Além disso, a DP afeta a qualidade de vida dos sujeitos. Baseado nisso, foram realizados dois estudos. O Estudo I teve como objetivo comparar as coordenações intra e intermembros durante a marcha entre sujeitos com DP e controle saudáveis. Dez sujeitos com DP (GP) e dez sujeitos controle (GC) foram submetidos a uma avaliação clínica e uma avaliação cinemática da marcha. Os resultados mostraram que o GP apresentou maiores durações da passada, do apoio e do balanço e menor comprimento da passada, velocidade, cadência e amplitudes de movimento que o GC. As coordenações intra e intermembros não diferiram significativamente entre os grupos. Assim, o GP apresentou alterações nas variáveis espaço-temporais e amplitudes de movimento articular, porém, os sujeitos foram capazes de se adaptar às limitações impostas pela doença e realizar uma marcha funcional, sem modificar o padrão de coordenação intra e intermembros. O Estudo II teve como objetivo avaliar os efeitos de um treino em esteira com aumento da carga corporal sobre a qualidade de vida, funções motoras e marcha de sujeitos com DP. Nove sujeitos com DP idiopática, em estágio moderado, participaram do estudo. O programa de treino foi dividido em três fases de seis semanas cada: treino da marcha em esteira com um aumento de 10% da carga corporal (A1), condição controle (fisioterapia convencional) (B) e treino em esteira novamente (A2). As avaliações e os treinos foram realizados na fase on do ciclo da medicação. Os resultados mostraram melhora no escore total e nos subitens mobilidade, atividades da vida diária e cognição relacionados à qualidade de vida e melhora das funções motoras. Houve também um aumento nas forças propulsivas, comprimento da passada, velocidade e extensão do quadril após o treino. Concluímos que o treino em esteira com aumento de carga corporal promoveu melhora da qualidade de vida e de variáveis importantes para a manutenção da marcha funcional de sujeitos com DP, mostrando-se uma alternativa promissora para otimizar os processos de reabilitação em combinação com a fisioterapia convencional.

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