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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.
121

The impact of foam rolling on explosive strength and excitability of the motor neuron pool

Abels, Kristin Marie 03 December 2013 (has links)
To assess acute performance-related effects of foam rolling, this study investigated the immediate effects of a standard foam rolling protocol on explosive strength of the plantarflexors and alpha motor neuron excitability in the soleus. Explosive strength was measured via vertical jump height (JUMP) and the Reactive Strength Index (RSI) obtained from a single leg drop jump. Alpha motor neuron excitability was measured by H reflex amplitude as H wave to M wave ratio (HM) obtained from the soleus muscle. JUMP and RSI measures were analyzed from nineteen subjects (12 male, 7 female) HM data were analyzed from 15 subjects (9 male, 6 female). Subjects attended one day of practice and instruction for the single leg drop jump and one day for data collection. One leg was randomly assigned to be the test leg (FL) and the other as the control (NL). The reported dominant leg and gender were also recorded for each subject. Subjects performed two single leg drop jumps per leg from a box height of 30 cm and then 10 soleus H reflexes were obtained. The intervention, which followed standard professional guidelines, consisted of 2.5 minutes of foam rolling for the FL and rest for the NL, followed by a 5 minute warm up on a cycle ergometer. The best jump and the average HM ratio were chosen for analysis. For each variable a post/pre ratio was calculated for statistical analysis. A 2x2x2 factor ANOVA with repeated measures on both factors was used for each variable. Analysis revealed no statistically significant differences for any of the variables, either as main effects or any of the interaction effects. Subjects trended towards a slightly larger post-intervention decrease in JUMP and RSI for the FL than the NL but this was not significant. It was concluded that a 2.5 minute intervention of foam rolling had no acute effect on explosive strength of the plantarflexors or alpha motor neuron excitability of the soleus. / text
122

Alterações motoras, comportamentais e histopatológicas após injeção intracerebroventricular de liquor de pacientes com esclerose lateral amiotrófica em ratos / Motor, behavioral and histopathological changes after intracerebroventricular cerebrospinal fluid injection of patients with amyotrophic lateral sclerosis in rats

Gois, Auderlan Mendonça de 26 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease that affects the somatic motor system through the degeneration of upper and lower motors neurons. Evidence suggests that the cerebrospinal fluid (CSF), which is in direct contact with the nervous system, has soluble substance that could cause injuries in motor neurons. Animal models that express mutant ALS associated genes have been created to study the various etiopathological mechanisms which manifest themselves similarly to that occur in ALS patients. However, these models best represent the etiology of the disease in familiar cases and there is not yet an animal model that represents the characteristics of the disease in sporadic form, despite the similarity between familiar and sporadic cases. Thus, the aim of this study was to evaluate the motor and histological changes after intracerebroventricular injection (i.c.v.) of CSF from ALS sporadic patients in rats. 43 seven-month-old Wistar rats were used, coming from the sectoral animal facility of the Department of Physiology at the Federal University of Sergipe. The study was divided into two experiments: (I) with a single administration i.c.v. of the CSF and (II) with repeated administration i.c.v. of the CSF. In the experiment I, the animals were divided into 3 groups: control (CTR, artificial CSF solution), non-ALS (N-ALS, CSF of patients without neurological disease) and ALS (ALS, LCR of patients with sporadic ALS) who received a single injection i.c.v. (7.5μL) and one week after were subjected to motor tests: strength test, catalepsy test, open field test and walking test once a week for 30 days. In the Experiment II, animals were divided into 3 groups: control (CTR) Non-ALS (N-ALS) and ALS and they received daily injection for 6 days, i.c.v. (5.0μL). Throughout the treatment the animals underwent the motor tests already mentioned. After the tests, in both experiments, rats were anesthetized, perfused, their spinal cords were removed and subjected to histological analysis by hematoxylin-eosin for general morphological observation. In the first experiment ,in ALS group, motor alteration was observed in the strength test, open field and in the walking test, accompanied by a reduction of motor neurons and glial cells in the thoracic and lumbar regions of the spinal cord. In the second experiment, Also in the ALS group, it was observed driving change in catalepsy, open field and in the walking test, accompanied by an increase of glial cells in the lumbar region of the spinal cord. Data presented in this study show that the CSF management of ALS patients can cause pathogenic mechanisms similar to those seen in humans and other animal models of ALS. / A Esclerose Lateral Amiotrófica (ELA) é uma doença neurodegenerativa progressiva, que afeta o sistema motor somático através da degeneração dos neurônios motores superiores e inferiores. Evidências apontam que o líquido cefalorraquidiano (LCR), que está em íntimo contato com o sistema nervoso, apresenta substâncias solúveis que podem provocar lesões em neurônios motores. Modelos animais que expressam genes mutantes associados à ELA foram desenvolvidos, para o estudo dos mais diversos mecanismos etiopatológicos que se manifestam de forma similar aos que ocorrem em pacientes com a doença. Entretanto, esses modelos representam melhor a etiologia da doença em casos familiares e, apesar da semelhança entre casos familiares e esporádicos, ainda não se tem um modelo animal que represente características da doença nesta última. Diante disso, o objetivo do presente trabalho foi avaliar as alterações motoras e histológicas após injeção intracerebroventricular (i.c.v.) de LCR de pacientes com ELA esporádica em ratos Wistar. Foram ultilizados 43 ratos Wistar, com idade aproximada de sete meses, provenientes do Biotério Setorial do Departamento de Fisiologia da Universidade Federal de Sergipe. O trabalho foi dividido em 2 experimentos: (I) com uma única administração i.c.v. de LCR e (II) com administrações repetidas i.c.v. de LCR. No experimento I os animais foram divididos em 3 grupos, controle (CTR, solução de LCR artificial), não-ELA (NELA, LCR de pacientes sem doenças neurológicas) e ELA (ELA, LCR de paciente com ELA esporádica) que receberam uma única injeção i.c.v. de 7,5 μL e após uma semana foram submetidos aos testes motores: teste de força, catalepsia, campo aberto e teste de marcha uma vez por semana durante 30 dias. No experimento II, os animais foram divididos em 3 grupos, controle (CTR), Não-ELA (N-ELA) e ELA que receberam uma injeção diária, durante 6 dias, i.c.v. de 5 μL. Ao longo do tratamento, os animais foram submetidos aos testes motores acima mencionados. Após os testes, em ambos experimentos, os ratos foram anestesiados, perfundidos, suas medulas removidas e submetidas à análise histológica pela coloração de hematoxilina-eosina para observação morfológica geral. No experimento I, no grupo ELA, foi observado alteração motora no teste de força, campo aberto e no teste de marcha, acompanhado por uma redução de neurônios motores e células gliais na região torácica e lombar da medula espinal. No experimento II, também no grupo ELA, foi observado alteração motora na catalepsia, campo aberto e no teste de marcha, acompanhado de um aumento de células gliais na região lombar da medula espinal. Os dados apresentados neste estudo mostram que a administração de LCR de pacientes com ELA pode provocar mecanismos patogênicos semelhantes aos observados em humanos e outros modelos animais de ELA.
123

The role of chaperone proteins in neurodegenerative diseases

Zhang, Xuekai January 2013 (has links)
Many neurodegenerative diseases are characterized by the accumulation of misfolded proteins that often share common morphological and biochemical features, and can similarly co-localize with several other proteins, including various chaperone proteins. Chaperone proteins, like heat shock protein 27 (HSP27), heme oxygenase 1 (HO-1) and clusterin, have been implicated as potent modulators of misfolded proteins, thus may play important roles in the pathogenesis of neurodegenerative diseases. The present study aims to investigate their roles in the pathogenesis of Frontotemporal lobar degeneration (FTLD), Alzheimer's disease (AD), Parkinson's disease (PD), and Motor neuron disease (MND) by determining their distribution and amount via immunohistochemical staining and western blotting in diseased and control subjects.There were distinct patterns of HSP27 and clusterin immunostaining in different brain regions. For HSP27, patients with AD and FTLD were in general more severely affected than were patients with MND and control subjects. For clusterin, patients with AD and FTLD were more severely affected than control subjects where neurons and glial cells were concerned, while patients with AD and control subjects were more severely affected than those with FTLD where diffuse and cored plaques were concerned. However, there were no obvious differences in the pattern of HO-1 immunostaining in various brain regions in patients with AD or FTLD relative to control subjects. Moreover, there was no association between HSP27, HO-1 and clusterin with disease or histological type, and the ‘classic’ neuropathological changes in FTLD, AD and MND were not immunoreactive to any of these proteins. There were significant correlations between the degrees of HO-1 and clusterin immunostaining in many brain areas for both AD and FTLD cases, and for all cases overall, but none between HSP27 and clusterin or HSP27 and HO-1. Present results suggest an involvement with ongoing cellular stress, misfolded or unfolded protein accumulation or the deficits/failure of other relevant protein quality control systems, in the pathogenesis of these neurodegenerative diseases. Present work may therefore have implications for the further development of ideas concerning the cause or treatment of neurodegenerative diseases where there is aberrant accumulation of misfolded, aggregated protein, and perhaps for conformational diseases in general. However, there are still many issues remain to be elucidated. Further research aimed at understanding the function and mechanisms of the chaperone system, and other protein quality control mechanisms, in the pathogenesis of neurodegenerative diseases is still needed.
124

Neuromuscular Function of the Shoulder Girdle and Upper Extremity Muscles in Individuals with Glenohumeral Labral Repair

Takeno, Katsumi January 2020 (has links)
No description available.
125

Quantitative Analysis of Novel Chemical and shRNA Based Methods to Increase Survival of Motor Neuron Protein Levels

Evans, Matthew C. 20 June 2011 (has links)
Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder that is the leading genetic cause of infantile death. SMA is caused by homozygous deletion or mutation of the survival of motor neuron 1 gene (SMN1). The SMN2 gene is nearly identical to SMN1, however is alternatively spliced. The close relationship to SMN1 results in SMN2 being a very power genetic modifier of SMA disease severity and a target for therapies. In this study we attempt to characterize novel chemical compounds identified as potential activators of the SMN2 gene. Additionally, we sought to determine the regulatory role individual HDAC proteins use to control expression of full length protein from the SMN2 gene. We used quantitative PCR to determine the effects of novel compounds and shRNA silencing of individual HDACs on the steady state levels of a SMN2-luciferase reporter transcripts. We determined that the compounds identified in multiple reporter high throughput screens increased SMN protein levels via transcriptional activation of the SMN2 gene. Other compounds identified in the same screen functioned post-transcriptionally, possibly stabilizing the SMN protein itself by decreasing degradation. Furthermore, we determined that reduction of individual HDAC proteins was sufficient to increase SMN protein levels in a transgenic reporter system. Knockdown of class I HDAC proteins preferentially activated the reporter by increased promoter transcription. Silencing of class II HDAC proteins maintained transcriptional activity; however silencing of HDAC 5 and 6 also appeared to enhance inclusion of an alternatively spliced exon. This collective work defines a quantitative RNA based protocol to determine mechanism of SMN reporter increase in response to any chosen treatment method. Additionally, this work highlights HDAC proteins 2 and 6 as excellent investigative targets. These data are important to the basic understanding of SMN expression regulation and the refinements of current therapeutic compounds as well as the development of novel SMA therapeutics.
126

Neural Correlates of Adaptive Responses to Changing Load in Feeding <i>Aplysia</i>

Gill, Jeffrey Paul 29 May 2020 (has links)
No description available.
127

Efekt prolongovaného strečinku na kontrakturu spastického svalu před a po aplikaci botulotoxinu - A / The effect of prolonged stretching on spastic muscle contracture before and after Botulinum toxin A application

Miňová, Zuzana January 2021 (has links)
A large proportion of patients with central motoneuron lesions is at risk of spastic paresis and formation of contractures. One of the therapeutic techniques used in patients with spastic paresis is prolonged stretching. The theoretical part summarizes the knowledge regarding spastic paresis, its clinical evaluation, the development of contractures and therapeutic interventions, especially botulinum toxin (BTX) and stretching. The aim of this study was to compare the effectiveness of prolonged stretching on spastic muscle contracture before and after BTX application. In our retrospective comparative study there were included 30 patients divided into two groups. The first group consisted of 15 patients performing prolonged stretching of the m. rectus femoris (m. RF) for three months according to Guided Self-rehabilitation Contract of Professor J. M. Gracies. The second group (15 patients) performing the same procedure, but at the same time BTX was injected into the m. RF. We monitored the change in passive knee joint range of motion into flexion and the change in 10MWT time. Statistical evaluation showed that the difference in knee joint range of motion after three months of performing prolonged stretching was statistically insignificant (p=0.194). The difference in knee joint range of motion after...
128

The Role of Muscle and Nerve in Spinal Muscular Atrophy

Iyer, Chitra C. 07 June 2016 (has links)
No description available.
129

A Muscle Perspective on the Pathophysiology of Amyotrophic Lateral Sclerosis : Differences between extraocular and limb muscles

Harandi, Vahid M. January 2016 (has links)
Background: Amyotrophic lateral sclerosis (ALS) is a late-onset progressive neurodegenerative disorder. ALS has been traditionally believed to be primarily a motor neuron disease. However, accumulating data indicate that loss of contact between the axons and the muscle fibres occurs early; long before the death of motor neurons and that muscle fibres may initiate motor neuron degeneration. Thus, the view of ALS is changing focus from motor neurons alone to also include the muscle fibres and the neuromuscular junctions (NMJs). While skeletal muscles are affected in ALS, oculomotor disturbances are not dominant features of this disease and extraocular muscles (EOMs) are far less affected than limb muscles. Why oculomotor neurons and EOMs are capable to be more resistant in the pathogenetic process of ALS is still unknown. The overall goal of this thesis is to explore the pathophysiology of ALS from a muscle perspective and in particular study the expression and distribution of key neurotrophic factors (NTFs) and Wnt proteins in EOMs and limb muscles from ALS donors and from SOD1G93A transgenic mice. Comparisons were made with age-matched controls to distinguish between changes related to ALS and to ageing. Results: Brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3) and neurotrophin-4/5 (NT-4) were present in EOMs and limb muscles at both mRNA and protein levels in control mice. The mRNA levels of BDNF, NT-3 and NT-4 were significantly lower in EOMs than in limb muscles of early and/or late control mice, indicating an intrinsic difference in NTFs expression between EOMs and limb muscles. qRT-PCR analysis showed significantly upregulated mRNA levels of NT-3 and GDNF in EOMs but significantly downregulated mRNA levels of NT-4 in limb muscles from SOD1G93A transgenic mice at early stage. The NTFs were detected immunohistochemically in NMJs, nerve axons and muscle fibres. The expression of BDNF, GDNF and NT-4 on NMJs of limb muscles, but not of EOMs, was significantly decreased in terminal stage ALS animals as compared to the limb muscles of the age-matched controls. In contrast, NTFs expression in intramuscular nerve axons did not present significant changes in either muscle group of early or late ALS mice. NTFs, especially BDNF and NT-4 were upregulated in some small-sized muscle fibres in limb muscles of late stage ALS mice. All the four Wnt isoforms, Wnt1, Wnt3a, Wnt5a and Wnt7a were detected in most axon profiles in all human EOMs with ALS, whereas significantly fewer axon profiles were positive in the human limb muscles except for Wnt5a. Similar differential patterns were found in myofibres, except for Wnt7a, where its expression was elevated within sarcolemma of limb muscle fibres. β-catenin, a marker of the canonical Wnt pathway was activated in a subset of myofibres in the EOMs and limb muscle in all ALS patients. In the SOD1G93A mouse, all four Wnt isoforms were significantly decreased in the NMJs at the terminal stage compared to age matched controls. Conclusions: There were clear differences in NTF and Wnt expression patterns between EOM and limb muscle, suggesting that they may play a role in the distinct susceptibility of these two muscle groups to ALS. In particular, the early upregulation of GDNF and NT-3 in the EOMs might play a role in the preservation of the EOMs in ALS. Further studies are needed to determine whether these proteins and the pathways they control may be have a future potential as protecting agents for other muscles.
130

Genetics of amyotrophic lateral sclerosis

Belzil, Véronique Valérie 02 1900 (has links)
La sclérose latérale amyotrophique (SLA) est la maladie des neurones moteurs la plus fréquente, affectant 4-6 individus par 100,000 habitants à l’échelle mondiale. La maladie se caractérise par une faiblesse et une atrophie musculaire suite à la dégénérescence des neurones du cortex moteur, tronc cérébral et moelle épinière. Les personnes atteintes développent les premiers symptômes à l’âge adulte et la maladie progresse sur une période de trois à cinq ans. Il a été répertorié qu’environ 10% des patients ont une histoire familiale de SLA; 90% des gens affectés le sont donc de façon sporadique. La découverte il y a 19 ans de mutations dans le gène zinc/copper superoxide dismutase (SOD1), présentes dans 15-20% des cas familiaux de SLA et environ 2% du total des individus affectés, a été l’événement déclencheur pour la découverte de variations génétiques responsables de la maladie. La recherche sur la génétique de la SLA a connu une progression rapide ces quatre dernières années avec l’identification de mutations dans de nouveaux gènes. Toutefois, même si certains de ces gènes ont été démontrés comme réellement liés à la maladie, la contribution d’autres gènes demeure incertaine puisque les résultats publiés de ceux-ci n’ont pas, à ce jour, été répliqués. Une portion substantielle de cas reste cependant à être génétiquement expliquée, et aucun traitement à ce jour n’a été démontré comme étant efficace pour remédier, atténuer ou prévenir la maladie. Le but du projet de recherche de doctorat était d’identifier de nouveaux gènes mutés dans la SLA, tout en évaluant la contribution de gènes nouvellement identifiés chez une importante cohorte multiethnique de cas familiaux et sporadiques. Les résultats présentés sont organisés en trois sections différentes. Dans un premier temps, la contribution de mutations présentes dans le gène FUS est évaluée chez les patients familiaux, sporadiques et juvéniles de SLA. Précisément, de nouvelles mutations sont rapportées et la proportion de mutations retrouvées chez les cas familiaux et sporadiques de SLA est évaluée. De plus, une nouvelle mutation est rapportée dans un cas juvénile de SLA; cette étude de cas est discutée. Dans un deuxième temps, de nouvelles avenues génétiques sont explorées concernant le gène SOD1. En effet, une nouvelle mutation complexe est rapportée chez une famille française de SLA. De plus, la possibilité qu’une mutation présente dans un autre gène impliqué dans la SLA ait un impact sur l’épissage du gène SOD1 est évaluée. Finalement, la dernière section explique la contribution de nouveaux gènes candidats chez les patients atteints de SLA. Spécifiquement, le rôle des gènes OPTN, SIGMAR1 et SORT1 dans le phénotype de SLA est évalué. Il est souhaité que nos résultats combinés avec les récents développements en génétique et biologie moléculaire permettent une meilleure compréhension du mécanisme pathologique responsable de cette terrible maladie tout en guidant le déploiement de thérapies suite à l’identification des cibles appropriées. / Amyotrophic lateral sclerosis (ALS) is the most common of motor neuron diseases, affecting 4-6 individuals per 100,000 individuals worldwide. ALS is characterized by muscle weakness and atrophy caused by the degeneration of neurons located in the motor cortex, brain stem and spinal cord. This fatal disease generally has an adult onset and progresses over a three to five year period. While 10% of patients affected have a family history of the disease, 90% of cases do not and are considered sporadic. The finding of mutations in the zinc/copper superoxide dismutase gene (SOD1) gene 19 years ago in about 15-20% of familial ALS (FALS) patients and approximately 2% of overall cases developed the interest of identifying rare genetics variants causing the disease. The ALS research field experienced a rapid progression during the last four years as mutations in new genes have been identified. While mutations in some of those new genes have been clearly linked to ALS, the role of others is still questionable and so far has not been positively replicated in other populations. Importantly, a significant portion of cases still need to be genetically explained and, unfortunately, there is still no effective treatment to cure, attenuate or prevent the disease. The aim of this Ph.D research project was to identify new ALS mutated genes while analysing the causative role of other newly identified genes in a large familial and sporadic ALS cohort of different origins. The results presented here are categorized into three different sections. First, the contribution of FUS mutations to familial, sporadic and juvenile ALS is analysed. Specifically, new FUS mutations are reported in ALS cases and the proportions of variants present in the tested familial and sporadic ALS cohorts are assessed. In addition, a new mutation is reported in a juvenile ALS patient, and this interesting case is discussed. Second, new genetic avenues are explored for the SOD1 gene. Precisely, a new and complex SOD1 mutation is reported in a French ALS family. Moreover, the possibility that other ALS mutated genes influence SOD1 splicing events is evaluated. Third, the contribution of new candidate genes is evaluated. Precisely, the contribution of OPTN, SIGMAR1 and SORT1 genes to the ALS phenotype is assessed. Hopefully, our different findings combined with recent developments in genetics and molecular biology will permit a better understanding of the pathological mechanisms involved in the disease and will lead to the identification of the right targets in order to develop appropriate therapeutics for ALS patients.

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