Thèses : « Neuromuscular spindle »

1

Stevenson, Deja Lee. « Whole-Body Vibration and Its Effects on Electromechanical Delay and Vertical Jump Performance ». Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd867.pdf.

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Patten, Robert Michael. « Muscle spindle morphology in the tenuissimus muscle of the golden syrian hamster ». Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29747.

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The tenuissimus is a long, thin hindlimb skeletal muscle which in hamsters contains about 200 extrafusal muscle fibers. Embedded in this richly innervated muscle is a continuous array of 16-20 closely packed muscle spindles suggesting that it may play a role in hindlimb proprioception. This high spindle density also makes the muscle ideal for the isolation and harvesting of these sensory receptors. In this correlative light and electron microscopic study, freshly frozen specimens were first prepared for serial microscopic analysis. Camera lucida reconstruction of spindle distribution showed a close proximity to the main artery and nerve in the central core of the muscle. Oxidative enzyme and myosin ATPase staining profiles were examined in both the intrafusal and extrafusal fiber populations. Type I and type II extrafusal fibers were present in even numbers and were distributed evenly throughout muscle cross-sections. Enzyme staining varied along the lengths of the three intrafusal fiber types. The fine structure of spindles was examined using transmission (TEM), conventional scanning (SEM), and high resolution scanning electron microscopy (HRSEM). For conventional SEM, isolated spindles were first fixed in 2.5% buffered glutaraldehyde, followed by 1% osmication, and mechanical disruption of the outer capsule under the dissecting microscope. Preparation for HRSEM included aldehyde/osmium fixation and freeze-cleavage of entire tenuissimus muscles in liquid N₂. Selective extraction of the cytosol with 0.1% OsO4 permitted the visualization of numerous intracellular structures. In these specimens, the capsular sleeve showed a multilayered pattern of vesicle-laden cells with variant surface topography in certain locations. Punctate sensory nerve endings adhered intimately to the surfaces of underlying intrafusal fibers in the equatorial and juxtaequatorial regions. By TEM and HRSEM these endings appeared crescent-shaped and were enveloped by external laminae. Each profile contained a plethora of mitochondria and cytoskeletal organelles. The methodology used in this study provides, for the first time, a three-dimensional view of the exquisite cytological architecture of this neuromuscular receptor.
Medicine, Faculty of
Graduate

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Thompson, Karen Jane. « The identification and progress towards isolation of an atypical glutamate receptor in muscle spindle primary afferent nerve terminals ». Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=232393.

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Hypertension affects 1 billion individuals worldwide and is the major contributing factor to cardiovascular disease. However, the WHO considers current antihypertensive drug therapies inadequate, highlighting a need for a novel approach to hypertension management. Baroreceptors are a promising drug target, and express an unusual glutamate receptor coupled to phospholipase D (PLD-GluR). The PLD-GluR has not been isolated and characterised, which is an important step towards its use as a drug target. A good source of the PLD-GluR is muscle spindle primary afferent nerve terminals, the largest mechanoreceptor in the body. This study thus focuses upon the identification and progress towards isolation of the PLD-GluR from muscle spindle primary afferent nerve terminals. A novel dissection method for high yield extraction of muscle spindles from a high density source, the rat deep masseter muscle, was developed for Western blotting and mass spectrometry screens of all GluRs. Western blots showed spindle homogenate contained a low molecular weight mGluR5 isoform and GluK2. Immunofluorescence showed mGluR5 was expressed on putative nociceptors, not mechanosensory nerve terminals. However, spindle mechanosensory nerve terminals labelled brightly for GluK2, as did baroreceptor nerve terminals. Furthermore, GluK2 appears to be the only GluR subunit on these mechanoreceptors, although mass spectrometry and affinity chromatography could not successfully isolate this receptor. Finally, piezo2 has recently been suggested as the major mechanotransducer protein. However, no evidence was found for piezo2 expression in adult spindle mechanosensory nerve terminals in adult rats or mice. As previous studies have largely focussed on adolescent mice, this could represent a developmental difference. Conversely, a number of candidate mechanosensory proteins, such as TRPs, were identified by a targeted mass spectrometry approach. This provides good candidates for future research. Collectively, this study indicates both spindle and baroreceptor mechanosensory nerve terminals express GluK2, suggesting it is at least a component of the PLD-GluR, and therefore potentially represents a novel drug target for treating hypertension.

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Vitry, Florian. « Effets aigus et chroniques de l’électrostimulation appliquée au niveau du nerf moteur : importance du retour afférent ». Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK087.

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L'objectif de cette thèse était d’étudier l'impact de protocoles d’électrostimulation favorisant un recrutement indirect des unités motrices (UM) via les afférences sensorielles et induisant le développement d’extra force, sur le système neuromusculaire. Ces protocoles associent une grande largeur d’impulsion, une faible intensité de stimulation, des hautes et basses fréquences et sont appliqués sur le nerf moteur. L’étude des effets de ces protocoles sur la fatigue neuromusculaire lors d’une application aiguë a fait l’objet de la première étude qui a montré que pour un impact équivalent sur la capacité maximale de production de force, les basses fréquences de stimulation limitaient la diminution de force au cours d’une session d’électrostimulation comparativement aux hautes fréquences. L’application de manière chronique de ces protocoles lors d’un entraînement a fait l’objet de la deuxième étude. Les résultats ont montré des gains de force importants malgré les faibles intensités de stimulation et des adaptations nerveuses qui étaient dépendantes de la fréquence de stimulation. Les résultats de ces deux études ont aussi permis de mettre en évidence l’importance du phénomène d’extra force sur les adaptations induites. Ainsi, l’étude de ce dernier phénomène a fait l’objet de la troisième étude. Les résultats ont montré que lorsque le recrutement initial des UM était indirect, l’extra force était présente pour toutes les fréquences de stimulation. De plus, le développement de l'extra force a induit une diminution de l’excitabilité spinale après les basses fréquences de stimulation et une augmentation après les hautes fréquences. La dernière étude de ce travail s’est intéressée aux mécanismes expliquant ces modulations spinales. Les résultats ont montré que le mécanisme de dépression post-activation pourrait expliquer la diminution observée après les basses fréquences, tandis que ce mécanisme serait compensé par la présence de courants entrants persistants, entraînant une augmentation de l’excitabilité des motoneurones après les hautes fréquences de stimulation. L’ensemble de ces résultats souligne l’importance du retour afférent aux adaptations neuromusculaires induites après une application aiguë et chronique de l’électrostimulation
The aim of this thesis was to investigate the effects of electrical stimulation protocols favouring an indirect motor units’ (MU) recruitment via sensory axons activation and giving rise to extra force development, on the neuromuscular system. These protocols use wide pulse duration, low stimulation intensity, low and high stimulation frequencies and are applied over the motor nerve. The aim of the first study was to examine the effects of these protocols on the extent and origin of neuromuscular fatigue during an acute application. Results showed that for a similar impact on maximal force generating capacity, low stimulation frequencies limit force decreases during the stimulation trains as compared to high stimulation frequencies. The aim of the second study was to investigate the effects of chronic application of these protocols. Results showed important torque gains after the training period despite the low stimulation intensity used, while the induced neural adaptations were frequency-dependent. Results of these two studies also highlighted the importance of the phenomenon of extra torque on induced adaptations. Thus, the aim of the third study was to determine the conditions permitting the occurrence of extra torque, by modulating the frequency and intensity of stimulation. Main results showed that when the initial MU recruitment was mostly indirect, the developed torque was higher than the one expected for the given stimulation parameters, independently of the stimulation frequency, suggesting that the indirect MU recruitment plays a preponderant role in the occurrence of extra torque. Moreover, a frequency-dependent impact on spinal excitability was observed, resulting in a decrease after the low stimulation frequency and an increase after the high frequency. Consequently, the last study investigated the mechanisms responsible for the distinct modulation of spinal excitability. Results showed that the decrease in spinal excitability observed after the low stimulation frequency could be attributed to increased homosynaptic post-activation depression, while this latter mechanism could have been compensated by an enhanced motoneuron excitability as a result of persistent inward currents after the high stimulation frequency. All these results underline the importance of the afferent volley to the induced neuromuscular adaptations after acute and chronic electrical stimulation application

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Daniels, Rachael J. « Molecular analysis of spinal muscular atrophy ». Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259878.

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Shinohara, André Luís. « Células satélites e fusos neuromusculares em músculos estriados de ratos desnervados por longo período ». Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-05112012-185039/.

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O músculo estriado esquelético apresenta em sua constituição células satélites (CS) que se encontram em estado quiescente localizadas entre o sarcolema e a lâmina basal das fibras musculares. As CS podem ser ativadas, diferenciando em mioblastos, contribuindo para regeneração e/ou crescimento do tecido muscular. Os Fusos neuromusculares são mecanorreceptores localizados no interior dos músculos esqueléticos considerados a unidade contrátil reguladora, monitorando a velocidade e duração do alongamento do músculo. Está composto de fibras intrafusais (FIF), circundadas por uma bainha de tecido conjuntivo e encontra-se paralelo às fibras extrafusais. A desnervação promove alterações no músculo esquelético, tanto em CS, quanto nos fusos neuromusculares. Este trabalho analisou quantitativamente as FIF e a proliferação de CS em músculos esquelético de ratos desnervados por longo período. Foram utilizados ratos Wistar. Os animais foram divididos em grupos desnervados e controle. Os músculos Sóleo e Extensor longo dos dedos (EDL) foram desnervados experimentalmente. Após os períodos de 0, 12, 16, 19, 30 e 38 semanas, os músculos foram dissecados, removidos e preparados histológicamente. A porcentagem de CS em músculos imediatamente após desnervação aumenta em relação ao músculo normal e depois decresce em ambos os músculos. Durante o progresso do tempo de desnervação ocorreu um aumento no número de FIF, se comparado com o grupo normal. O número de CS diminui significantemente entre os períodos de desnervação, em ambos os grupos. Nos músculos estudados quanto menor a porcentagem de CS maior é o número de FIF e, aumentando o tempo de desnervação, diminui o número de CS. Em relação às FIF, no grupo controle com o aumento do tempo, o número de fibras não se altera. Já para o grupo experimental, com o aumento do tempo de desnervação, diminui o número de CS e aumenta o número de FIF significantemente. Concluimos então que nos músculos desnervados por longo período ocorre diminuição na porcentagem de células satélites e aumento no número de FIF. Finalmente nossos resultados sugerem que entre 16ª e 19ª semana pós-desnervação encontra-se o melhor período para reinervação de um músculo desnervados.
The skeletal muscle consists of satellite cells (SC) which are in a quiescent state located between the sarcolemma and basal lamina of the muscle fibers. The SC can get activated, differentiating into myoblasts, contributing to regeneration and/or growth of muscle tissue. The neuromuscular spindles are mechanoreceptors located within the skeletal muscle and are considered as contractile regulatory unit, monitoring the speed and duration of muscle stretching. It is composed of Intrafusal muscle fibers (FIF), surrounded by a sheath and is parallel to extrafusal fibers. Denervation cause changes in skeletal muscles both in the CS and neuromuscular spindles. This study analyzed quantitatively the FIF and the proliferation of CS in rat skeletal muscle, denervated for long period. We used Wistar rats to perform this study. The animals were divided into control and denervated groups. The soleus and extensor digitorum longus (EDL) were denervated experimentally. After periods of 0, 12, 16, 19, 30 and 38 weeks, the muscles were dissected, removed and were prepared for histological analysis. The percentage of SC in muscles immediately after denervation, increases in relation to normal muscle and later decreases in both the groups. During the process of denervation, there was an increase in FIF when compared with normal group. The number of SC reduces significantly between the periods of denervation in both the groups. In the muscles studied, the smaller the percentage of SC, higher is the number of FIF and increase in the duration of denervation, reduces the number of SC. As for FIF, with the increase in time in control group, the number of fibres was unaltered. However, in the experimental group, with increase in the time of denervation, the number of SC decreases while there is increase in the number of FIF significantly. We thus conclude that in denervated mucles for long period, there is decrease in the percentage of satellite cells and increase in FIF. Finally our results suggest that the period between 16th and 19th week of post denervation is the best time for reinnervation of denervated muscle.

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Eftekharzadeh, Bahareh. « Androgen receptor aggregates studies in vitro and in a transgenic mouse model of Spinal Bulbal Muscular Atrophpy (SMBA) ». Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/294596.

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Spinal bulbar muscular atrophy (SBMA) is a rare hereditary neuromuscular disease caused by the elongation of a polymorphic polyglutamine (polyQ) tract in the N-terminal region of the transactivation domain (NTD) of androgen receptor (AR). Although the molecular basis of SBMA is not yet fully understood, the observation of nuclear inclusions containing AR fragments in specific tissues of SBMA patients has led to the suggestion that it is linked to AR aggregation. To characterize the molecular mechanism of this process we have investigated the structural properties of the polyQ tract present in AR as well as the early stages of its oligomerization in vitro by nuclear magnetic resonance (NMR) spectroscopy in solution. To study the structural property of the AR aggregates in tissue, the Seprion ligand was used for quantification of AR aggregate load in a SBMA mouse model. A combination of atomic force microscopy (AFM), transmission electron microscopy (TEM) and high-resolution microscopy was used to investigate the Seprion ligand captured aggregates from muscle and spinal cord tissue. The results indicated that aggregated structures from spinal cord extract differ remarkably from the fibrillar species isolated from muscle tissue. We found that the AR fibrils in the muscles accumulate and increase their length as the animals age. Our results indicate that there are differences between the androgen receptor variants in muscle and spinal cord, with more N-terminally truncated AR found in muscle compared to spinal cord. We propose that truncated AR forms aggregates and leads to AR fibrillar species in muscles and that mutant AR97Q plays a role in the recruitment of partner interacting proteins in an age-related fashion. Our studies into the elucidation of the early stages of oligomerization indicated that the polyQ tract is partially alpha-helical, a propensity that increases with its length. In addition, a specific region of the N-terminus of the NTD, distinct from the polyQ tract, appears to be responsible for the inter-molecular interactions that nucleate AR aggregation. Studying the interactions between AR and the molecular chaperones Hsp40 and Hsp72 respectively, by solution NMR spectroscopy we found that the Hsp72 and Hsp40 both bind to (23)FQNLF(27) motif, whereas the Hsp40 binds additionally to (54)LLLQQQQ(61). These findings provide a simple mechanism for the disassembly of the complex between AR and molecular chaperones required for androgen receptor function and emphasize the therapeutic potential of allosteric regulators of Hsp72 and Hsp40 and provide new insights into the role of the chaperone machinery in protein quality control in neurodegenerative diseases.
L'atròfia muscular espinobulbar (SBMA) és una malaltia neuromuscular hereditària causada per una elongació d'una regió de poliglutamines localitzada en el domini de transactivació del receptor d'andrògens (AR). Malgrat que la base molecular d'aquesta malaltia encara no es coneix del tot, l'observació d'inclusions nuclears que contenen fragments del receptor dóna suport a la hipòtesi que està associada a l'agregació de l'AR. Per tal de caracteritzar el mecanisme molecular d'aquest procés hem investigat les propietats estructurals de la regió de poliglutamines del receptor així com els primers estadis de la seva oligomerització in vitro mitjançant espectroscòpia de ressonància magnètica nuclear (NMR) en solució. Per tal d'estudiar les propietats estructurals dels agregats que es formen en els teixits hem fet servir el lligand Seprion per aïllar els agregats que es formen en un model animal de SBMA. Mitjançant una combinació de microscòpia de força atòmica (AFM), microscòpia electrònica de transmissió (TEM) i microscòpia d'alta resolució hem caracteritzat els agregats formats tant en el múscul com en la medul·la espinal en aquest model animal. Els resultats indiquen que els agregats de l'AR que es formen en el múscul son clarament diferents d'aquells que es formen en la medul·la i, a més, que el fenotip dels animals empitjora a mesura que s'acumulen agregats en el primer d'aquests teixits. Els nostres resultats indiquen que les diferències que observem entre els agregats que es formen en el múscul i aquells que es formen en la medul·la estan associades a la presència de fragments d'AR en el primer d'aquest teixits. Proposem doncs, que formes truncades d'AR agreguen per formar espècies fibril·lars en el múscul del model animal i que aquestes provoquen el fenotip, que empitjora amb l'edat, perquè, en agregar, recluten proteïnes nuclears que altrament serien solubles. El nostre estudi dels primers estadis del mecanisme d'oligomerització indica clarament que la regió de poliglutamines és parcialment helicoïdal i que aquesta propensitat augmenta amb la seva longitud. A més hem identificat una regió del domini de transactivació, allunyada de la regió de poliglutamines, com a responsable de les primeres interaccions intermoleculars que tenen lloc durant el mecanisme d'oligomerització. En el nostre estudi de la interacció entre AR i les xaperones moleculars Hsp40 i Hsp72 hem descobert, mitjançant NMR, que totes dues proteïnes s'uneixen al motiu (23)FQNLF(27) del domini N-terminal i que l'Hsp40 s'uneix, a la vegada també al motiu (54)LLLLQQQQ(61) que hi ha a l'inici de la regió de poliglutamines. Aquestes descobertes suggereixen un senzill mecanisme per a desensamblatge del complex entre l'AR i les xaperones moleculars que té lloc durant l'activació del receptor per l'hormona testosterona, emfatitzen el potencial terapèutic de reguladors al·lostèrics de Hsp40 i Hsp72 i contribueixen a una millor comprensió del paper que les xaperones moleculars tenen en el control de qualitat de proteïnes en malalties neurodegeneratives.

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Murray, Lyndsay M. « Synaptic vulnerability in spinal muscular atrophy ». Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4419.

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Mounting evidence suggests that synaptic connections are early pathological targets in many neurodegenerative diseases, including motor neuron disease. A better understanding of synaptic pathology is therefore likely to be critical in order to develop effective therapeutic strategies. Spinal muscular atrophy (SMA) is a common autosomal recessive childhood form of motor neuron disease. Previous studies have highlighted nerve- and muscle-specific events in SMA, including atrophy of muscle fibres and postsynaptic motor endplates, loss of lower motor neuron cell bodies and denervation of neuromuscular junctions caused by loss of pre-synaptic inputs. Here I have undertaken a detailed morphological investigation of neuromuscular synaptic pathology in the Smn-/- ;SMN2 and Smn-/-;SMN2;Δ7 mouse models of SMA. Results imply that synaptic degeneration is an early and significant event in SMA, with progressive denervation and neurofilament accumulation being present at early symptomatic time points. I have identified selectively vulnerable motor units, which appear to conform to a distinct developmental subtype compared to more stable motor units. I have also identified significant postsynaptic atrophy which does no correlate with pre-synaptic denervation, suggesting that there is a requirement for Smn in both muscle and nerve and pathological events can occur in both tissues independently. Rigorous investigation of lower motor neuron development, connectivity and gene expression at pre-symptomatic time points revealed developmental abnormalities do not underlie neuromuscular vulnerability in SMA. Equivalent gene expression analysis at end-stage time points has implicated growth factor signalling and extracellular matrix integrity in SMA pathology. Using an alternative model of early onset neurodegeneration, I provide evidence that the processes regulating morphologically distinct types of synaptic degeneration are also mechanistically distinct. In summary, in this work I highlight the importance and incidence of synaptic pathology in mouse models of spinal muscular atrophy and provide mechanistic insight into the processes regulating neurodegeneration.

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Francis, Michael J. « Physical mapping around the SMA gene using yeast artificial chromosomes (YACs) ». Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259879.

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Nataraj, Raviraj. « FEEDBACK CONTROL OF STANDING BALANCE USING FUNCTIONAL NEUROMUSCULAR STIMULATION FOLLOWING SPINAL CORD INJURY ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1302482539.

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Mecca, Jordan. « Rôle des cellules souches musculaires dans la physiopathologie de l’amyotrophie spinale ». Electronic Thesis or Diss., Sorbonne université, 2019. http://www.theses.fr/2019SORUS261.

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L’amyotrophie spinale (SMA), est une maladie neuromusculaire caractérisée par une dégénérescence des motoneurones (MN), une atrophie musculaire et une paralysie conduisant à une mort précoce dans les formes les plus sévères. La SMA est due à une réduction de la protéine ubiquitaire SMN résultant de mutations homozygotes dans le gène SMN1. Longtemps considérée comme une pathologie purement neuronale, la SMA apparaît aujourd’hui comme une pathologie multisystémique affectant de nombreux tissus périphériques, dont le muscle squelettique et les cellules souches musculaires (CS). Avec les premiers succès de la thérapie génique basée sur l’AAV9-SMN, émergent aussi des incertitudes quant aux effets à long terme de ces thérapies en particulier sur l’intégrité du système neuromusculaire. Ces travaux se sont inscrits dans cette problématique, et apportent un nouvel éclairage sur l’implication des CS musculaires dans la physiopathologie de la SMA. Nous avons observé une diminution du nombre de CS dans les muscles de patients SMA Type II, qui pourrait résulter d’un défaut d’engagement des CS vers la quiescence et d’une perte des CS quiescentes par apoptose. Grâce au modèle murin Pax7CreERT2/+;SmnF7/F7, nous avons démontré que cette déplétion des CS induite par le déficit en SMN induit, à long terme, une perte sélective des MN-α accompagnée de changements phénotypiques des fibres musculaires. Enfin, nous avons montré une dérégulation du profil d’expression des miARN dans les CS de souris SMA, et identifié de potentielles cibles thérapeutiques pour le développement de futures stratégies thérapeutiques combinées, restaurant SMN et préservant le système neuromusculaire sur le long terme
Spinal muscular atrophy (SMA) is a neuromuscular disorder characterized by motor neurons (MN) degeneration, muscle atrophy and paralysis leading to premature death in the most severe forms. SMA is due to a reduction of the ubiquitous protein called SMN resulting from homozygous mutations in SMN1 gene. Long considered as a purely neuronal disease, SMA appears now as a multisystemic disease affecting many peripheral tissues, including skeletal muscle and muscle stem cells (SC). With the first successes of AAV9-SMN-based gene therapy, uncertainties emerge about the long-term effects of these therapies, particularly regarding the integrity of the neuromuscular system. This work is in line with this problematic, and shed new light on the involvement of muscle SC in SMA pathophysiology. We observed a decreased number of SC in the muscles of SMA Type II patients, which could result from reduced ability of SMN-deficient SC to commit to quiescence and a loss of quiescent SC by apoptosis. Using the murine conditional KO model Pax7CreERT2/+;SmnF7/F7, we demonstrated that this SC-depletion induced by SMN deficiency leads, in the long term, to a selective loss of α-MN and phenotypic changes in muscle fibers. Finally, we showed a deregulation of miRNA expression profile in SMA mouse SC, and identified potential new therapeutic targets for the development of future combined therapeutic strategies, restoring SMN and preserving the neuromuscular system in the long term

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Marcato, Sonia. « Empathy and executive functions in neuromuscular diseases ». Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3426336.

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Objective: the relationship between Executive Functions (EFs) and Empathy, in particular Theory of Mind (ToM), is well known, considering neuropsychological performances and the neural correlates underpinning each one. Evidences regarding deficits on ToM skills related to impairment in EFs are nowadays well known in Amyotrophic Lateral Sclerosis (ALS) and Myothonic dystrophy (DM1). The aim of the present study was the evaluation of ToM and its association with EFs in four neuromuscular diseases in which EFs can be impaired, and so: Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), Facioscapulohumeral dystrophy (FSHD) and X-linked Spinal and Bulbar Muscular Atrophy (X-SBMA). Moreover, also abilities related to Affective Empathy have been investigated. Methods: the study involved 25 DMD patients, 21 BMD patients, 21 FSHD patients, 64 X-SBMA patients and 145 healthy controls matched for age, education and gender. Both patients and controls completed tests and questionnaires with the aim to assess EFs, ToM and Affective Empathy abilities. Results: deficits in EFs have been found only in DMD patients. EFs impairment resulted to be associated with deficits in ToM ability but also with problems related to Affective Empathy. Conclusions: DMD patients without mental retardation manifest problems on EFs. These deficits are related to impairments in ToM abilities and Affective Empathy skills. These results can give an important contribution to clinical practice: know the Empathic abilities of patients may be useful to clinicians in order to create a good alliance which is extremely useful in the compliance of treatments and therapeutic choices.
Obiettivo: la relazione tra Funzioni Esecutive (EFs) ed Empatia, in particolare la Teoria della Mente (ToM), è ben nota, sia se si considerano le evidenze neuropsicologiche e se si pensa ai correlati neurali che sottostanno a questi costrutti. Oggigiorno sono presenti numerose ricerche, in patologie come la Sclerosi Laterale Amiotrofica (ALS) e la Distrofia Miotonica (DM1), che evidenziano che deficit nelle capacità di ToM sono legati alla compromissione delle EFs. Lo scopo del presente studio è la valutazione delle abilità legate alla ToM e la sua associazione con le EFs in quattro patologie neuromuscolari in cui le EFs possono essere compromesse, quindi la distrofia muscolare di Duchenne (DMD), la distrofia muscolare di Becker (BMD), la distrofia facioscapolomerale (FSHD) e l’atrofia muscolare spinale e bulbare (SBMA). Inoltre, sono state valutate anche le abilità legate all’empatia affettiva. Metodo: lo studio ha previsto il reclutamento di 25 pazienti DMD, 21 pazienti BMD, 21 pazienti FSHD, 64 pazienti SBMA e 145 controlli sani abbinati per età, scolarità e genere. Sia i pazienti che i controlli hanno completato test e questionari allo scopo di valutare le EFs, la ToM e l’empatia affettiva. Risultati: sono stati rilevati deficit nelle EFs solamente nei pazienti affetti da DMD. La compromissione delle EFs è risultata essere associata alla compromissione della ToM e dell’empatia affettiva. Conclusioni. Pazienti affetti da DMD senza ritardo mentale hanno manifestato problemi nelle EFs. Inoltre, questi deficit sono risultati essere legati a problemi nella ToM e nelle abilità di empatia affettiva. Questi risultati possono offrire un importante contributo alla pratica clinica: conoscere la abilità empatiche dei pazienti può essere utile al personale sanitario al fine di creare una buona alleanza con il paziente, cosa estremamente utile se si pensa alla compliance ai trattamenti e alle scelte terapeutiche.

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Uzel, Sébastien G. M. « Microfluidic and optogenetic technologies to model spinal cord development and neuromuscular junction formation and function ». Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/103850.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.
"June 2015." Cataloged from PDF version of thesis.
Includes bibliographical references (pages 106-118).
Motor neurons located in the spinal cord and innervating muscle cells throughout the body are responsible for virtually all motor functions, from locomotion to respiration or speech. They arise from differentiation of progenitor cells within the neural tube under spatiotemporally well-defined morphogen concentration profiles, and extend axons into the peripheral nervous system following a precisely orchestrated sequence of events involving secreted chemo-attractants and repellents and dynamic expression of the corresponding ligand receptors. Finally, they form neuromuscular junctions, the synapses that transmit electrical signals to the muscle effectors. Failure for these motor neurons to develop or function properly, caused by developmental or neurodegenerative genetic disorders, or as a result of traumatic injuries, lead to highly incapacitating or even lethal malformation and conditions. Microfabricated platforms and optogenetic technologies have proven to be valuable tools to control the microenvironment, biochemical cues and the stimulation applied to neuronal tissues. Precise control of the geometry of microfluidic devices together with their ability to host 3D cell culture has enhanced the physiological relevance of such neuronal tissues relative to traditional 2D culture assays. And the ability to selectively excite neuronal cells with light has opened tremendous opportunities in the field of neuroscience. In this thesis, we combine these two technologies to stimulate and subject cells to chemical and physical microenvironments that emulate their in vivo counterpart. First, we present a microfluidic platform that generates orthogonal concentration gradients and emulates the confined appearance of motor neurons within the developing spinal cord. Then, we introduce a new device capable of forming a 3D compartmentalized neuron-muscle coculture and demonstrate remote stimulation of the myofibers by the motor neurons resulting in muscle contraction. By targeting the stem cells from which the motor neurons are derived with the light sensitive ion channel Channelrhodopsin, we form, in this microfluidic device, the first in vitro light-activatable neuromuscular junction. Keywords: microfluidics, optogenetics, morphogenesis, cell migration, neuromuscular junctions.
by Sébastien G. M. Uzel.
Ph. D.

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Miller, Emily Michele. « Exercise-Induced Low Back Pain and Neuromuscular Control of the Spine - Experimentation and Simulation ». Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/37507.

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Low back pain (LBP) is associated with altered neuromuscular control of the trunk, as well as impaired performance during functional tasks highly dependent upon trunk neuromuscular control. Comparing measurements between individuals with and without LBP does not distinguish whether the LBP individual exhibits altered neuromuscular control only while experiencing LBP versus at all times. Additional insight was gained on the relationship between trunk neuromuscular control and LBP by investigating individuals who experience recurrent exercise-induced LBP (eiLBP). To differentiate the effects of LBP from individual differences, comparisons were made between episodes of pain and no pain within eiLBP individuals, and between eiLBP individuals while pain free and a group of healthy controls. Three studies were completed based on repeated measurements from both eiLBP and healthy individuals. Study 1 investigated effects of eiLBP on fundamental measures of neuromuscular control, including intrinsic trunk stiffness and the paraspinal reflex delay using a series of pseudo-random position perturbations. eiLBP individuals exhibited increased stiffness compared to healthy controls unaffected by the presence of pain, and increased reflex delays concurrent only with pain. Study 2 investigated effects of eiLBP on seated sway during a functional task involving maintaining balance. Seat and trunk kinematics were obtained while participants balanced on a wobble chair at two difficulty levels. eiLBP individuals exhibited impaired seat measures at all times, with altered trunk measures only while in pain and when the task was not challenging. Study 3 investigated effects of eiLBP on the underlying control of seated sway using a model of wobble chair balance. Quantified neuromuscular control indicated increases in proportional and noise gains for a challenging level compared to an easy level, more so for eiLBP individuals compared to controls and while experiencing pain compared to pain free. Overall, fundamental measures, seated sway measures, and identified control parameters using a model of wobble chair balance were all affected by the presence of pain within the eiLBP individuals and/or the eiLBP individuals compared to healthy controls. Therefore, this study shows that some characteristics appear to be inherent to the LBP individual, while others are only concurrent with pain.
Ph. D.

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Thomson, Sophie Rose. « Examining mechanisms underlying the selective vulnerability of motor units in a mouse model of Spinal Muscular Atrophy ». Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/9615.

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Spinal Muscular Atrophy (SMA) is a childhood form of motor neuron disease that causes a progressive paralysis that, in its most severe form, results in death before two years of age. There is currently no cure or treatment for SMA. SMA is caused by a reduction in levels of Survival Motor Neuron (SMN) protein, which results in the degeneration of lower motor neurons. This degeneration is first observed at the neuromuscular junction (NMJ), where pre-synaptic nerve terminals belonging to the motor neuron become dysfunctional and degenerate during the early stages of disease. Several previous studies have shown that the some populations of motor neurons appear to have a resistance to SMA pathology, while other neighbouring populations are vulnerable. In this study, we attempted to elucidate the cause of this vulnerability spectrum. Initially, we characterised the relative vulnerability of ten different motor unit pools in an established mouse model of severe SMA and attempted to correlate these vulnerabilities with quantified aspects of motor unit morphology. From this study, no significant correlation could be found with any aspect of motor unit morphology examined, suggesting that morphological parameters of motor neurons do no influence their relative susceptibility. We then attempted to identify changes in basal gene expression between protected and vulnerable pools of motor units using microarray analysis. Motor unit pools were labelled using a retrograde tracer injected into muscles that had previously been identified as having highly vulnerable or resistant motor units. Labelled motor neuron cell bodies were then isolated from the spinal cord using laser capture micro-dissection and RNA was extracted for microarray analysis. From this study, we identified several molecular pathways and individual genes whose expression levels compared the gene expression profiles of vulnerable and resistant motor units. Thus, molecular differences between motor neuron pools likely underlie their relative vulnerability to degeneration in SMA. Lastly, we attempted to identify a novel peptide that could be used to label synapses, including neuromuscular junctions, in vivo. This would allow us to non-invasively visualise degenerating NMJs and other synapses in human patients without the need for a biopsy. Such a tool would be extremely valuable in assessing the effectiveness of drug trials, both in human patients and animal models, and may also contribute to earlier diagnosis of motor neuron disorders. To identify a potentially suitable peptide, we used a phage display library and panned for peptides that specifically bound to the outer surface of synapses using synaptosome preparations. From this panning we successfully enriched two peptides, the sequences of which were used to manufacture fluorescently tagged peptides.

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Amir, Nili S. « Frequency of Complications Following Spinal Fusion in Children with Cerebral Palsy ». eScholarship@UMMS, 2020. https://escholarship.umassmed.edu/gsbs_diss/1070.

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Background: Neuromuscular Scoliosis is a frequent complication of Cerebral Palsy that requires surgical management including spinal fusion. The objective of this observational study was to describe differences in the frequency of postoperative complications in children with Cerebral Palsy following spinal fusion surgery compared to children with Idiopathic Scoliosis. Methods: The 2016 Kids’ Inpatient Database was queried to identify pediatric patients (old) with concurrent diagnoses of Cerebral Palsy and Neuromuscular Scoliosis undergoing spinal fusion surgery. Cases were compared to children without Cerebral Palsy and with a diagnosis of Idiopathic Scoliosis undergoing the same procedure. Fitted Poisson regression analysis with robust variance was performed to estimate relative risks in the frequency of various clinical complications while adjusting for several potentially confounding variables of importance. Results: A total of 660 cases and 5,244 comparators were identified. Compared to children with Idiopathic Scoliosis, children with Cerebral Palsy were younger (13.6 vs. 14.3 years), more likely to be male (54% vs. 23%), and more likely to have had governmental insurance (52% vs. 32%). They also had longer hospital lengths of stay (8 days vs. 4 days). After adjusting for a number of potentially confounding sociodemographic and clinical variables, children with Cerebral Palsy were more likely to have postoperative pulmonary, gastrointestinal, and surgical complications, receive blood transfusions, and be admitted to the ICU. Conclusions: Children with Cerebral Palsy have an increased risk of complications following spinal fusion surgery leading to longer hospital stays. These results further inform surgical decision-making and anticipatory guidance for these children and their caregivers.

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Schafer, Carol Linda. « Development of a functional neuromuscular stimulation (FNS) muscle training program to prepare paraplegics for standing ». Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/25845.

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Wheelchair-bound paraplegics are in an unnatural, almost all-day sitting position. This is physiologically disadvantageous as it may cause increased abdominal pressure, renal dysfunction, pressure sores, muscle atrophy and osteoporosis. Thus it would be beneficial, physiologically and psychologically, for a paraplegic to be able to stand for temporary periods of time. As a result of the muscle atrophy and functional degeneration that follows a spinal cord injury, it is essential for paraplegics to undergo a muscle restrengthening program, using Functional Neuromuscular Stimulation (FNS), before standing up under FNS control can be attempted. Six healthy spinal cord injured subjects with spinal lesions between CS and T9 (two tetraplegics and four paraplegics) exercised their quadriceps muscles at home using a portable two-channel FNS muscle stimulator. The muscles were exercised against an increasing load to maximise the training effect. Inclined standing exercise, under FNS control, was performed in the Inclistand. The subjects' general state of health and fitness were assessed, namely their responses during a maximal arm ergometry exercise test, arm muscle function, lung function, blood biochemistry and their dietary habits. Subjects have shown improvement in quadriceps muscle strength, fatigue resistance and muscle bulk to varying degrees - according to their individual circumstances. The tetraplegics responded in a different manner to that of the paraplegics. The muscle strength increased significantly by a mean (+SD) of 97,8 + 59,6% and 171,2 + 118,1% for the four paraplegics, left and right leg respectively. There was a mean improvement of 16% in fatigue resistance in the left leg (p=0,08), while the mean response of the right leg varied. Quadriceps muscle bulk increased by 4,43 + 3,4% (left) and 2,7 + 2,1% (right) (0,05<p<0,l). The amount of subcutaneous fat around the mid-thigh decreased significantly by 4,73 + 1,4% (left) and 3,43 + 1,1% (right leg). The group was in a state of general well-being, with the exception of one subject whose serum cholesterol concentration fell within the high risk category. This study therefore showed that the FNS was sucessful in improving the quadriceps muscle strength, bulk and fatigue response of the SCI people in our research group. The valuable experience gained from this FNS study will be used to improve the present program.

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Souron, Robin. « Adaptations fonctionnelles et nerveuses à l'entraînement par vibration locale : du sujet sain à la rééducation ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSES055/document.

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La recherche de méthodes permettant de lutter contre le déconditionnement neuromusculaire à la suite par exemple d’une opération chirurgicale ou d’une immobilisation prolongée intéresse la communauté scientifique depuis de nombreuses années. Ce projet visait à proposer la technique de vibration locale (LV) comme une méthode alternative aux méthodes classiquement utilisées (e.g. vibration corps entier, stimulation électrique neuromusculaire) pour lutter contre ce déconditionnement neuromusculaire. Le premier objectif de ce travail de thèse était de déterminer les effets d’une application aigüe de LV sur la fonction neuromusculaire des muscles fléchisseurs dorsaux et extenseurs du genou de sujets sains. Nos résultats montrent une modulation de l’excitabilité du système nerveux central en réponse à l’application aigüe de LV, ce qui nous a permis d’envisager de potentielles adaptations si cette technique était utilisée de façon répétée sur plusieurs semaines. Ainsi, la seconde orientation de ce travail était d’évaluer les effets d’une application chronique (entraînement) de LV sur les propriétés fonctionnelles (force, hauteur de saut) et nerveuses (mesurées par stimulation magnétique transcrânienne) de sujets sains, jeunes et âgés. Nos résultats ont montré qu’un entraînement par LV était efficace pour améliorer les capacités fonctionnelles de ces deux populations, ces gains s’accompagnant d’adaptations nerveuses. Ces travaux nous ont alors conduits à la mise en place d’une dernière étude (en cours) à visée clinique, qui évaluait l’efficacité de LV en rééducation post-ligamentoplastie du ligament croisé antérieur du genou
There is a need to find new methods to limit neuromuscular deconditioning that occurs after a surgery or prolonged immobilization. This thesis aimed to assess local vibration (LV) training as an alternative to methods classically used (e.g. whole body vibration, neuromuscular electrical stimulation) to fight against neuromuscular deconditioning. The first aim of this project was to determine the effects of a 30-min acute exposure to LV on the neuromuscular function of dorsiflexor and knee extensor muscles in a healthy population. Our results showed that acute LV intervention changed central nervous system excitability, allowing us to consider long-term adaptations to prolonged LV. Thus, the second aim of this thesis was to assess the effects of a chronic application (training) of LV on functional (maximal strength, squat jump performance) and neural (assessed with transcranial magnetic stimulation) properties of healthy young and old subjects. Our results showed that 4 to 8 weeks of LV increase functional capacities that were due to neural adaptations. Based on these results, an on-going study assessing the effectiveness of LV during a rehabilitation program for subjects who suffered from anterior cruciate ligament lesion has been proposed

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Bose, Prodip Kumar. « Wobbler mouse : early detection of motoneuron disease, therapeutic evaluation of nutrition, neuropeptides & ; their antagonists, and the effects on neuronal sprouting in cervical spinal cord / ». Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19118168.

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Sene, Marcela de Oliveira. « Efeitos da estimulação elétrica neuromuscular sobre o gasto energético de lesados medulares ». Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-01092003-110729/.

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Lesões na medula espinhal atingem um grande número de pessoas, devido a traumas, doenças congênitas ou adquiridas. Para estes tipos de lesões não há cura e os indivíduos lesados medulares dependem de tratamento através de fisioterapia ou órteses que auxiliem na recuperação de possíveis funções perdidas. A Estimulação Elétrica Neuromuscular (EENM) tem sido pesquisada com essa proposta: reabilitar pessoas portadoras de lesão medular ou disfunções do aparelho locomotor. Muitos estudos já foram desenvolvidos na área de estimulação elétrica neuromuscular, avaliando a marcha, o ato de levantar-se ou outros movimentos. Um ponto em comum entre estes estudos é a preocupação com os efeitos fisiológicos da EENM, como por exemplo o gasto energético. Diante disto, o objetivo deste projeto foi avaliar os efeitos da EENM sobre o gasto energético de lesados medulares. Foi observado o consumo de oxigênio durante o repouso, a marcha e a recuperação. A avaliação proposta foi realizada por método indireto e as análises estatísticas foram realizadas através do teste ANOVA ONE WAY. Os resultados sugerem os voluntários tiveram recuperação fisiológica. Entretanto novas pesquisas são necessárias, com outras variáveis sendo avaliadas.
Lesions in the spinal cord affect a great number of individuals, either due to traumas or to congenital or acquired diseases. Such lesions are incurable, and the injured patients depend on physiotherapy or orthosis to aid in the recovery of lost functions. The Neuromuscular Electrical Stimulation (NMES) has been researched with this purpose: rehabilitating spinal cord injured patients, or those with motor system dysfunction. Several studies have already been developed in the field of neuromuscular electrical stimulation, assessing gait, the act of getting up or other everyday movements. All these studies bear something in common: the concern with the physiologic effects of NMES, such as the energy consumption. Hence, the objective of this project was to evaluate the effects of NMES on the energy cost of spinal injured patients. The consumption of oxygen was assessed during rest, gait and the recovery period. The proposed evaluation was made through indirect method, and the statistical analyses through the ANOVA ONE WAY test. The results to suggest that the volunteers had phisyological recovery. However, news reserchs there are needs, with others variable to be estimated.

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Wilkenfeld, Ari (Ari Jacob) 1974. « Computer simulation of the neuromuscular reaction to electrical stimulation of the spinal cord of a spinalized frog ». Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42812.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
Includes bibliographical references (leaves 51-52).
submitted by Ari Wilkenfeld.
S.M.

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Manhães, Renata Borges. « A engenharia de reabilitação e as características psicossociais de pessoas com lesão medular submetidas a um programa de estimulação elétrica neuromuscular ». Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-28102004-100130/.

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A estimulação elétrica neuromuscular é um recurso reabilitacional funcional que tem como propósito a recuperação dos movimentos dos membros superiores ou inferiores. Com este recurso, é possível a pessoas que possuem uma lesão medular e que vêem suas vidas modificadas pelo advento da lesão, executarem ações que possam facilitar a sua independência nas habilidades diárias, uma vez que mudanças em seu esquema corporal e limitações reais às suas atividades cotidianas são observadas nestes casos. Acredita-se que seja comum a presença de reações psicológicas a este tratamento, porém, poucos estudos foram registrados até o momento. Considerando-se que uma intervenção que aborde aspectos físicos, psicológicos e sociais destas pessoas é indispensável a qualquer processo reabilitacional, esta pesquisa teve como objetivos identificar e analisar características psicossociais de usuários do programa de estimulação elétrica neuromuscular realizado no Hospital das Clínicas da Universidade Estadual de Campinas, Departamento de Ortopedia e Traumatologia da Faculdade de Ciências Médicas, Laboratório de Biomecânica e Reabilitação do Aparelho Locomotor. Suas concepções, reações e expectativas frente a este tipo de reabilitação também foram investigados, além da identificação das principais necessidades destas pessoas, oferecendo subsídios para a condução de um tratamento psicoterápico adequado ao quadro caracterológico das pessoas com lesão medular submetidas à estimulação elétrica neuromuscular, de forma a favorecer a realização de um processo reabilitacional que os contemplem em sua dinâmica biopsicossocial. Para isso, os participantes desta pesquisa foram divididos em dois grupos distintos. Os que se encontravam no primeiro ano de tratamento e os que o realizavam há mais de um ano. Foi utilizado um roteiro de entrevista semi estruturada que teve como propósito conhecer aspectos, tais como, a visão da pessoa com lesão medular sobre sua própria deficiência, formas de enfrentamento, vida social e familiar, bem como, suas concepções e expectativas no que diz respeito à reabilitação por meio da estimulação elétrica neuromuscular. Os entrevistados consideraram como uma de suas metas, a recuperação total ou parcial das funções que lhes foram subtraídas com a lesão medular, considerando efeitos positivos com a utilização deste tratamento, no alcance de melhorias físicas e psicossociais. Não obstante, eles procuram investir em vários outros aspectos de suas vidas, que não somente o reabilitacional, como por exemplo, os profissionais, familiares, sociais e afetivos
Neuromuscular electrical stimulation is a functional resource for rehabilitation, which aims recover the motions of inferior and superior limbs. With this resource, it is possible for spinal cord injury patients, who had their lives changed due to this injury, to execute actions that can make their independency to every day abilities easier, once changes in their body structure and real limitations to daily activities were noticed in this case. It is believed that the remark of psychological reactions are usual for this treatment, however, a few studies were registrated until the moment. In regarding to an intervention that deals with this patients physical and social aspects is essential to any rehabilitation process, this research aims to identify and analyze users psycho-social characteristics of neuromuscular electrical stimulation program made at Campinas State University hospital, Orthopedic and Traumatology Department of Medical Science School, Laboratory of Biomechanics and Rehabilitation of Inferior Limbs. Its concepts, reactions and expectations toward this kind of rehabilitation were also investigated, as well as the identification for the leading of a psychotherapeutic treatment appropriate to the characterization of the process of spinal cord injury patients who were subjected to neuromuscular electrical stimulation in order to be biased toward the achievement of a rehabilitational process, which gives to the spinal cord injured person in his/her biopsycho social dynamic. For this, subjects of this research were divided in two different groups. The first group, people who were in the first year of treatment and the second group, people who had been in treatment for more than one year. A schedule of a half-standard interview was used and aimed to know aspects such as spinal cord injured person´s point of view about his/her own disability, how he/she faces it, social and family life as well as his/her concepts and expectations regarding to rehabilitation through neuromuscular electrical stimulation. The total or partial recovering of the functions that were taken by the spinal cord injury was had as one of the patients´ goals, which were worried about the positive effects by using this treatment, within reach physical and psychosocial improvement. They tried to invest in many other aspects of life, such as professional, family, social and affective aspects

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Dachs, i. Cabanas Elisabet. « Caracterització fenotípica i assaig terapèutic en models murins transgènics d'atròfia muscular espinal ». Doctoral thesis, Universitat de Lleida, 2012. http://hdl.handle.net/10803/83624.

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L’atròfia muscular espinal (AME) és una malaltia d’origen genètic que afecta, majoritàriament a la població infantil. La malaltia cursa amb una mort de les motoneurones  i atròfia muscular. El gen implicat és el survival motor neuron (SMN) que està delecionat en un 95% dels casos. El nostre estudi està dividit en dues parts: 1- l’aprofundiment de les alteracions musculars en dos models animals murins transgènics que pateixen les formes més greus d’AME (Tipus 1-2) i 2- estudi dels possibles efectes terapèutics del liti en un d’aquests models d’AME. S’ha trobat alteracions greus en les unions neuromusculars d’animals nounats i prenatals en marcadors relacionats amb l’ancoratge de les vesícules a la membrana presinàptica, organització dels canals de calci presinàptics i altres proteïnes presinàptiques, desorganització i apoptosi de les cèl•lules musculars, apoptosi massiva del timus i alteracions generalitzades en els òrgans limfoides. L’estudi ultraestructural del múscul ens indica que hi ha una mort, per apoptosi, de les cèl•lules satèl•lit, confirmat amb la tècnica de TUNEL. L’augment de les apoptosi, però no es reflexa en un increment, per altra banda esperat, de la densitat dels macròfags. El tractament amb concentracions terapèutiques del liti no millora l’evolució de la malaltia en els ratolins que manifesten l’AME, s’observa una acumulació progressiva dels nivells de liti, provocant toxicitat en l’animal. L’efecte del liti inhibint la GSK3 no es tradueix en el increment d’expressió de SMN, tal com s’ha deduït d’alguns experiments publicats.
La atrofia muscular espinal (AME) es una enfermedad de origen genético que afecta, mayoritariamente a la población infantil. La enfermedad cursa con muerte de las motoneuronas y atrofia muscular. El gen implicado es el “survival motor neuron” (SMN) que está delecionado en un 95% de los casos. Nuestro estudio está dividido en dos partes: 1 - la caracterización de las alteraciones musculares en dos modelos animales murinos transgénicos que sufren las formas más graves de AME (Tipo 1-2) y 2 - estudio de los posibles efectos terapéuticos del litio en uno de estos modelos. Se han encontrado alteraciones pre y postnatales graves en las sinapsis neuromusculares a nivel de marcadores relacionados con el anclaje de las vesículas en la membrana presináptica, en la organización de los canales de calcio presinápticos y en otras proteínas presinápticas, Asimismo se ha hallado desorganización y apoptosis de las células musculares, apoptosis masiva del timo y alteraciones generalizadas en los órganos linfoides. El estudio ultraestructural del músculo nos revela muerte, por apoptosis, de las células satélite, confirmado con la técnica de TUNEL. El aumento de las apoptosis muscular no conlleva un incremento, por otra parte esperado, de la densidad de los macrófagos. El tratamiento con litio no mejora la evolución de la enfermedad en los ratones con AME. Se observa un incremento progresivo de los niveles de litio, provocando toxicidad en el animal. Por otra parte, el efecto del litio inhibiendo la GSK3 no se traduce en un aumento de la expresión de SMN, tal como se ha deducido de algunos experimentos publicados.
The spinal muscular atrophy (SMA) is a pediatric genetic disease. The SMA is a motor neuron disease that affects the motor neurons causing its death and muscle atrophy. The gene involved is the survival motor neuron (SMN) that is mutated in the 95% of the cases. Our study is divided into two parts: 1 – studies of the neuromuscular junction in two transgenic SMA murine models that develop the most severe forms of SMA (type 1-2) and 2 - study of the possible therapeutic effects of lithium on one of these models of SMA. We found severe alterations in the neuromuscular junctions of newborn animals and also in prenatal markers related to the vesicle docking at the presynaptic membrane, lack of organization of presynaptic calcium channels and defects in the expression of other presynaptic proteins. We found also, disruption and apoptosis of muscular cells, massive apoptosis of the thymus and widespread alterations in lymphoid organs. The ultrastructural study of muscle identifies apoptotic satellite cells that was confirmed by the TUNEL technique. The increase in apoptosis is not followed by the expected increase, in the macrophage density. Treatment with therapeutic concentrations of lithium does not improve the course of the disease in SMA mice. There was a progressive accumulation of lithium, causing toxicity in the animal. The effect of lithium inhibiting GSK3 does not determine an increased expression of SMN, as could be deduced from some published experiments.

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Vasconcelos, Neto Renata. « Marcha com estimulação eletrica neuromuscular em paraplegicos : angulos, pico de momento e teste de caminhada de seis minutos ». [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313754.

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Orientador: Alberto Cliquet Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-10T00:45:16Z (GMT). No. of bitstreams: 1 VasconcelosNeto_Renata_M.pdf: 2310953 bytes, checksum: a4ec42aa2d3d7698d2b27ec3f9f536f9 (MD5) Previous issue date: 2007
Resumo: objetivo deste estudo foi avaliar as características da cinemática, o pico do momento articular de flexão e extensão das articulações do quadril, joelho e tornozelo e o esforço cardiovascular durante a marcha assitida por estimulação elétrica neuromuscular (EENM) de pacientes paraplégicos. Um grupo foi formado por onze sujeitos saudáveis - grupo controle (GC) e o outro por dez sujeitos com paraplegia (GP) com lesão medular entre T4 e TIO. Os dados da cinemática e da cinética foram coletados por um sistema de seis câmeras ProReflex (Qualisys) e uma plataforma de força AMTI. O GP caminhou com o auxílio de um andador, utilizando uma órtese no tornozelo (ankle foot orthosis - AFO) e com quarto canais de EENM, que estimulou o grupo muscular quadríceps e o nervo fibular. O teste de caminhada de seis minutos foi realizado e mensurado a frequência cardíaca, a pressão arterial sistólica, a pressão arterial diastólica, a distância e a velocidade percorridas. Os resultados mostraram que os picos de flexão e extensão do momento articular das articulações analisadas,' o tamanho da passada, a cadência, a velocidade e a variação angular foram menores no GP, quando comparados ao GC. O teste de caminhada de sei5 minutos demonstrou um alto custo energético do GP durante a marcha. Os resultados sugerem que o treino de marcha com EENM em indivíduos paraplégicos tem um baixo risco de ocasionar lesões nas articulações dos membros inferiores e que este tipo de marcha requer um alto gasto energético podendo ser usado para melhorar o condicionamento cardiovascular destes pacientes
Abstract: The aim of this study was to evaluate kinematics characteristics, peak moment and the cardiovascular effort during neuromuscular electrical stimulation (NMES) stimulated gait of paraplegic patients. Eleven healthy control subjects (CG) and 10 paraplegic subjects (PG) with lesion levels between T4 and TIO were assessed. The kinematic and kinetic data were collected by a six-camera system ProReflex (Qualisys) and a force plate - AMTI. The PG walked aided by a walker, an ankle foot orthosis and a four channel NMES system, that stimulated the quadriceps muscular group and the fibular nerve. The six min walking test (6MWT) was done and heart rate, blood pressure and distance were measured. The kinetic results showed that in PG moment peaks, stride, cadence, speed and angle range were lower than in CG. The 6MWT demonstrated the high energy cost of PG during gait. Results suggest that NMES gait training for paraplegic individuaIs is of low risk towards causing lower lifub joint lesions and this type of walking also requires a high amount of energy and can be used to improve cardio respiratory conditioning to these patients
Mestrado
Pesquisa Experimental
Mestre em Cirurgia

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Benedetti, L. « ADULT SOD1 G93R ZEBRAFISH MODEL DEVELOPS HALLMARK FEATURES OF ALS AND DISPLAYS NEUROMUSCULAR JUNCTIONS DEFECTS AND SPINAL NEURONS HYPEREXCITABILITY AT EARLY DEVELOPMENTAL STAGES ». Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/244459.

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Amyotrophic Lateral Sclerosis (ALS) is an adult-onset neurodegenerative disease characterized by selective and progressive loss of motor neurons in the spinal cord, brain stem and motor cortex. Approximately 12% of familial and 1% of sporadic cases of ALS are associated to mutations in the gene coding for the antioxidant enzyme Cu-Zn Superoxide Dismutase type 1 (SOD1). Zebrafish is emerging as a powerful experimental model for the study of disorders affecting the nervous system and here we characterized the disease phenotype in adult zebrafish overexpressing the Sod1 ALS-linked mutation G93R (mSod1) and the wild-type Sod1 (wtSod1). Adult zebrafish expressing mutant Sod1 develop most of the main pathological features occurring in ALS: locomotor impairments, motor neurons degeneration, spinal cord and muscle atrophy, neuromuscular junctions loss, astrogliosis and inflammation. Interestingly, as it was reported in mice models of the disease, also in this model the overexpression of the wild-type form of Sod1 is associated to the development of mild alterations. Having completed the characterization of the pathological phenotype in the adult, we searched for precocious ALS hallmarks in zebrafish embryos and larvae. The optical transparency of zebrafish at early developmental stages allowed us to perform whole-mount fluorescence staining from which we studied the effects of the overexpression of wild-type or mutant Sod1 on spinal motor neurons development and neuromuscular junctions maturation. Mutant zebrafish embryos display precocious motor nerves branching defects while larvae present neuromuscular junctions maturation impairments and muscle fibers atrophy. The expression of mutant Sod1 is associated to precocious behavioral alterations in spontaneous tail coilings at 20 hpf, in touched evoked tail coiling responses at 48 hpf and in burst swimming responses at 96 hpf. In Sod1 G93R expressing embryos we detected spinal neurons hyperexcitability associated to the increased activity of the persistent sodium current INaP, and by the administration of riluzole, directly into the embryo water, we managed to pharmacologically modulate the spinal neurons electrical activity, the behavioral phenotype and the motor axons length. These results are extremely relevant since several studies demonstrated that ALS patients exhibit cortical hyperexcitability before any clinical sign of ALS and electrophysiological experiments performed in cultured mice embryonic and neonatal dissociated spinal motor neurons expressing mutant SOD1 G93A demonstrated neuronal hyperexcitability associated to the increased activity of the persistent sodium current INaP. This work demonstrates that the Sod1 G93R zebrafish model not only represents a valuable complement to other animal model for the study of ALS but also that it is a powerful model on its own to investigate ALS mainly thanks to the possibility to study locomotor circuits and potential pathogenetic mechanisms occurring at the very early stages of disease pathogenesis.

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Bulea, Thomas Campbell. « A Variable Impedance Hybrid Neuroprosthesis for Enhanced Locomotion after Spinal Cord Injury ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1333564164.

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Bittar, Cíntia Kelly. « Reabilitação de lesados medulares com estimulação elétrica neuromuscular = avaliação óssea e aspectos clínico e radiográfico dos pés e tornozelos ». [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313762.

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Orientador: Alberto Cliquet Júnior
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-18T01:34:35Z (GMT). No. of bitstreams: 1 Bittar_CintiaKelly_D.pdf: 5246806 bytes, checksum: 9260873ef7fa16dc2ede271dc0571bd7 (MD5) Previous issue date: 2010
Resumo: A lesão medular causa prejuízos nos aspectos físico, psicológico e social da pessoa. Há predomínio de indivíduos do sexo masculino, jovens e o principal motivo são os acidentes automobilísticos. A lesão neurológica e o desuso dos membros acometidos produzem espasticidades, contraturas, osteoporose e deformidades, principalmente nos pés. Uma estratégia para diminuir estas complicações nos lesados medulares é a estimulação elétrica neuromuscular (EENM). Há poucos estudos na literatura descrevendo o comportamento de pés e tornozelos de lesados medulares submetidos à EENM, bem como sobre avaliação da osteoporose nestes indivíduos utilizando UQC (ultrassonografia quantitativa de calcâneo). Portanto, o objetivo principal deste estudo foi analisar os efeitos da EENM nos pés e tornozelos de lesados medulares e compará-los a grupo de lesados que não realizam EENM e a grupo de indivíduos normais. O objetivo secundário é avaliar a utilidade da ultrassonografia quantitativa de calcâneo no diagnóstico de osteoporose em lesados medulares. No período de janeiro a outubro de 2009, trinta pacientes do ambulatório de lesados medulares no Hospital das Clínicas da Unicamp que realizam EENM (Grupo A) tiveram seus pés e tornozelos submetidos à avaliação clínica e radiográfica e foram comparados a grupo de lesados que não realizam EENM (Grupo B) e a grupo de indivíduos normais (Grupo C). Foi também avaliada a densidade óssea utilizando UQC e densitometria óssea (DEXA) de 15 pacientes que iniciariam EENM no ambulatório de lesados medulares no Hospital das Clínicas da Unicamp (Grupo D), comparando-a com um grupo de pacientes normais (Grupo E). A avaliação clínica dos pés e tornozelos envolveu deformidades, condições de pele e mobilidade articular da talocrural, da talocalcânea e do médio pé. A avaliação radiográfica consistiu na análise dos ângulos hálux valgo, intermetatarsal, ângulo talocalcâneo no sentido dorso plantar e perfil, tálus em relação ao primeiro osso metatarsal, calcâneo-solo e tibiocalcâneo. Para avaliação estatística foram utilizados o teste de Kruskal-Wallis, Mann- Whitney e Wilcoxon Pareado. Quando o valor de p < 0.05 houve diferença significativa. Em relação aos resultados dos grupos A, B e C, a mobilidade da articulação talocalcânea foi de 23,4º no Grupo A; 13,5º no Grupo B e 28,9º no Grupo C. Na comparação da mobilidade da talocalcânea entre os Grupos A e B, B e C foram constatadas diferenças significativas (0.0092 e 0.0034 respectivamente). Na articulação transversa do tarso a média da mobilidade foi de 22,5º no Grupo A; 15,3º no Grupo B e 24,1º no Grupo C. Comparando a mobilidade articulação transversa do tarso entre os Grupos A e B, B e C obteve-se diferenças significativas (respectivamente 0.0184 e 0.0022). A média da mobilidade da articulação do talocrural foi de 41,4º no Grupo A; 34,3º no Grupo B e 63,6º no Grupo C. Esta mobilidade, quando comparada entre os Grupos A e C, B e C apresentou diferenças significativas (0.0009 e 0.0008, respectivamente). A média da mensuração do ângulo do hálux valgo foi 17,5º para o Grupo A; 14,8º para o Grupo B e 15,6º para o Grupo C. A média do intermetatarsal foi 9,1º (Grupo A); 8,1º (Grupo B) e 10,1º (Grupo C). A média para o ângulo talocalcâneo em AP foi 23,5º (Grupo A), 18,9º (Grupo B) e 24º (Grupo C). A média do ângulo calcâneo-solo foi de 25º para o Grupo A; 25,3º para o Grupo B e 26,8º para o Grupo C. O ângulo talocalcâneo no perfil apresentou as seguintes médias: 44,7º para o Grupo A; 36,8º para o Grupo B e 31,1º para o Grupo C. Quando este ângulo foi comparado entre os Grupos A e C, B e C, houve diferenças significativas (0.0184 e 0.0040, respectivamente). A média do ângulo entre o tálus e o primeiro osso metatarsal foi 13,8º (Grupo A), 19,3º (Grupo B) e 4,0º (Grupo C). Este ângulo, quando comparado entre os Grupos A-C e B-C, apresentou diferenças significativas (0.0089 e 0.0075, respectivamente). A média do ângulo tibiocalcâneo no Grupo A foi de 81º, no Grupo B foi de 80,6º e no C de 81,8º. As deformidades encontradas nos pés dos sujeitos do Grupo A incluíram dois pacientes com dedos em garra e um com pés planos bilateral, enquanto no Grupo B foram encontrados um pé com úlcera grau I no maléolo lateral e um pé com úlcera no calcâneo. Em relação aos resultados da densidade óssea dos grupos D e E, os valores do T score no colo femoral com DEXA (0, 0022) e T score de calcâneo com UQC (0, 0005) apresentaram diferença significativa entre os grupos, com médias superiores no grupo dos normais em relação ao grupo de lesados medulares que iniciariam eletro-estimulação (p < 0.05). O grupo de lesados medulares apresentou diferenças significativas entre os T score da UQC e T score da coluna lombar e do colo com DEXA. Este estudo permitiu concluir que a EENM mantém pés e tornozelos de lesados medulares plantígrados e em posição adequada para deambulação. Essa constatação parece confirmar um aspecto favorável no caso de novas tecnologias permitirem que estes pacientes readquiram capacidade autônoma de marcha. Em relação à avaliação da densidade óssea pelo baixo estresse mecânico nos calcâneos de lesados medulares, pode-se concluir que a UQC não apresenta resultados que possam ser correlacionados com a DEXA para diagnóstico de osteoporose. Não é possível afirmar que UQC seja uma boa escolha para diagnóstico e acompanhamento dos lesados medulares
Abstract: Spinal cord injuries harms a person's physical, psychological and social aspects. It predominantly affects young individuals of the male gender, and is mainly caused by automobile accidents. Spasticity, contractures, and osteoporosis appear due to neurological lesions and disuse, increasing the risk for deformities, especially of the feet. A strategy to diminish these spinal cord injury complications is neuromuscular electrical stimulation (NMES). Few studies have described how the feet and ankles of patients with spinal cord injuries behave when subjected to NMES, and about the evaluation of osteoporosis in these individuals with the use of QUS (quantitative ultrasound of the calcaneus). Therefore the main objective of this study was to analyze the effects of NMES on the feet and ankles of spinal cord injuries patients and compare them with a group of lesion patients who did not undergo NMES, and a group of normal individuals. The secondary objective was to evaluate the use of quantitative ultrasound of the calcaneus in the diagnosis of osteoporosis in spinal cord injuries patients. From January to April 2008, 30 patients at the spinal cord injury ambulatory clinic at the Hospital das Clínicas da Unicamp (group A) were submitted to a clinical and radiographic assessment of their feet and ankles and compared with a spinal cord injury group that did not undergo NMES (group B) and with a group of normal individuals (group C). Bone density was also evaluated using QUS and bone densitometry (DEXA) in 15 patients who began undergoing NMES at the spinal cord injuries ambulatory clinic at the "Hospital das Clínicas da Unicamp" (Group D), and comparing them with the group of normal patients (Group E). The feet and ankle clinical assessment involved documentation of deformities, skin conditions, joint mobility of the ankle, subtalar and midfoot. Standard radiographs were used for the radiographic assessment, with dorsoplantar and profile incidences of support. It was measured the hallux-valgus angle, intermetatarsal angle, talocalcaneal angle, calcaneal-ground angle, talus in relation to the first metatarsal angle, and the tibiocalcaneal angle. For statistical evaluation the Kruskal-Wallis, Mann-Whitney and Wilcoxon Paired tests were used. When the p-valor was > 0.05 there was significant difference. As regards the results of Groups A, B and C, the mobility of the subtalar joint was 23.4º in Group A; 13.5º in Group B and 28.9º in Group C. In the comparison of subtalar mobility between Groups A and B, B and C significant differences were found (0.0092 and 0.0034 respectively). In the midfoot joint the mean mobility was 22.5º in Group A; 15.3º in Group B and 24.1º in Group C. When comparing the midfoot mobility among Groups A and B, B and C significant differences were obtained (0.0184 and 0.0022 respectively). The mean mobility of the ankle joint was 41.4º in Group A; 34.3º in Group B and 63.6º in Group C. When this mobility was compared between Groups A and B, B and C significant differences were presented (0.0009 and 0.0008 respectively). The mean measurement of the hallux valgus angle was 17.5º for Group A; 14.8º for Group B and 15.6º for Group C. The mean of the intermetatarsal angle was 9.1º (Group A); 8.1º (Group B) and 10.1º (Group C). The mean for the talocalcaneus angle in AP was 23.5º (Group A), 18.9º (Group B) and 24º (Group C). The mean of the calcaneal-ground angle was 25º for Group A; 25.3º for Group B and 26.8º for Group C. The talocalcaneal angle in profile presented the following means: 44.7º for Group A; 36.8º for Group B AND 31.1º for Group C. When this angle was compared between Groups A and C, B and C, there were significant differences (0.0184 and 0.0040, respectively). The mean angle between the talus in relation to the first metatarsal and first metatarsal was 13.8º (Group A), 19.3º (Group B) and 4.0º (Group C). When this angle was compared between Groups A-C and B-C, it presented significant differences (0.0089 and 0.0075, respectively). The mean tibiocalcaneal angle in Group A was 81º, in Group B 80.6º and in Group C it was 81.8º. The deformities found in the feet of subjects in Group A included two patients with clawed toes, and one with bilateral flat feet, while in Group B one foot with Grade 1 ulcer on the lateral malleolus and one foot with an ulcer on the calcaneus were found. As regards the bone density results of Groups D and E, the values of the T score in the femoral neck with DEXA (0. 0022) and T score of the calcaneus with QUS of the calcaneus (0. 0005) presented significant difference between the groups, with higher means in the normal group in comparison with the spinal cord injuries group, who began undergoing NMES (p > 0.05). The spinal cord injuries group presented significant differences between the T score of QUS of the calcaneus and the T score of the lumbar spine and the femoral neck with DEXA. It is possible to conclude that the partial-load NMES maintained the feet and ankles of patients with spinal cord injuries in an adequate walking position. This finding indicates a favorable aspect of new technologies that may allow these patients to regain independent walking capacity. As regards the evaluation of bone density due to the low mechanical stress on the heels of spinal cord injuries patients, it could be concluded that QUS did not present results that could be correlated with DEXA for the diagnosis of osteoporosis. It was not possible to affirm that QUS is a good choice for the diagnosis and follow-up of spinal cord injuries patients
Doutorado
Fisiopatologia Cirúrgica
Doutor em Cirurgia

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Elias, Leonardo Abdala. « Modelagem e simulação do sistema neuromuscular responsável pelo controle do torque gerado na articulação do tornozelo ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-02102013-150228/.

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O estudo do controle neurofisiológico do movimento tem sido realizado sob várias perspectivas. Experimentos com seres humanos são realizados durante a execução de uma dada tarefa motora e, frequentemente, mediante a aplicação de estímulos externos (elétrico, magnético ou mecânico) ao sistema neuromuscular. Estes experimentos fornecem uma grande quantidade de dados referentes ao funcionamento das redes neuronais e dos atuadores biomecânicos envolvidos nos procedimentos. Entretanto, alguns achados experimentais permanecem incompreensíveis, requerendo a utilização de outros recursos para elucidar quais mecanismos estão por trás dos resultados. Neste sentido, a modelagem matemática e a simulação computacional servem como parte importante destas ferramentas que são imprescindíveis para uma melhor compreensão dos mecanismos neurofisiológicos e biomecânicos por trás do controle do movimento. A presente tese de doutorado teve como objetivo prover um modelo neuromusculoesquelético biologicamente plausível capaz de investigar diferentes mecanismos responsáveis pelo controle do torque gerado na articulação do tornozelo. Este modelo teve como base um modelo neuromuscular previamente proposto, porém, que não incorporava uma série de elementos fundamentais para um estudo mais amplo do sistema motor. O novo modelo proposto contempla modelos de motoneurônios com dendritos ativos, proprioceptores musculares responsáveis pelas vias reflexas de curta e média latência, modelos que representam as características viscoelásticas dos músculos e um modelo biomecânico do ser humano durante a postura ereta quieta. O modelo foi aplicado a diferentes problemas relacionados ao funcionamento do sistema neuromusculoesquelético, que são tipicamente explorados por experimentos com seres humanos, e forneceu bases teóricas importantes para estes achados.
The neurophysiological control of movement has been studied from several standpoints. Human experiments are performed during the execution of a given motor task and, frequently, by applying an external stimulation (electrical, magnetic, or mechanical) to the neuromuscular system. These experiments provide a large amount of data concerning the functioning of the neuronal networks and biomechanical actuators involved in the procedures. Nonetheless, some experimental findings remain puzzling, so that other available resources should be used to clarify what mechanisms are behind these results. In this vein, the mathematical modeling and computer simulations are invaluable tools that may be used to better understand the neurophysiological and biomechanical mechanisms underlying the motor control. The present PhD thesis aimed at providing a biologically plausible neuromusculoskeletal model that was used to study different mechanisms involved in the control of the ankle joint torque. This model was based on a previous neuromuscular model, which did not employ several elements that are fundamental to a comprehensive evaluation of the motor system. The novel proposed model encompasses motor neuron models with active dendrites, muscle proprioceptors responsible for the short- and medium-latency reflex pathways, muscle models with the main viscoelastic features, and a biomechanical model of the human body during upright stance. It was applied to a series of problems frequently related to the functioning of the neuromusculoskeletal system and its main outcomes provided important theoretical bases for a set of experimental findings.

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Faleiro, Michelle R. 1987. « Delineating a requirement for Survival of Motor Neuron (SMN) protein in skeletal muscle tissue ». Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/664120.

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Spinal Muscular Atrophy (SMA) is an autosomal recessive neuromuscular disorder characterized by the degeneration of the lower motor neurons. It is caused by homozygous loss or mutations in the Survival Motor Neuron 1 (SMN1) gene, leading to a reduction of the amount of Survival Motor Neuron (SMN) protein. In human patients, an almost identical copy gene, SMN2, is unable to fully compensate for the lack of SMN1, due to a C to T transition in exon 7. Despite progress in the field, the cellular site of action of the SMN protein remains incomplete. Fully defining it is critical for clinical treatments and to enhance our understading of the basic biology of the disease. These questions have been addressed in large part through the study of SMA model organisms. These studies have shown that SMN is particularly important in motor neurons; additional experiments have explored various other tissues which may also be particularly sensitive to SMN, including skeletal muscle. Still, the role of muscle in SMA continues to be debated and the precise function of SMN in this tissue as it pertains to the pathology of the disease remain far from clear. This is partly because in vivo experiments performed to date cannot rule out the possibility that changes observed in muscle are simply occurring as a secondary effect of denervation due to pathology in the innervating motor neurons. As therapies for SMA evolve, these remain important questions to address. Accordingly, the goal of this research project has been to more precisely delineate the contributing role of muscle in the overall pathology/phenotype characteristic of SMA. Our results show that wild-type levels of SMN in muscle are absolutely critical to the maintenance of healthy muscle. Thus we believe that SMN functions cell-autonomously within this tissue to ensure its health and viability. Restoring protein to muscle is therefore expected to constitute a vital aspect of treating SMA in SMN repletion-type therapies.
La Atrofia Muscular Espinal (AME) es un trastorno neuromuscular autosómico recesivo caracterizado por la degeneración de las neuronas motoras inferiores. Es causada por pérdida homocigótica o mutaciones en el gen de la neurona motora de supervivencia (SMN1), que conduce a una reducción de la cantidad de proteína de neurona motor de supervivencia (SMN). En los pacientes humanos, un gen de copia casi idéntico, SMN2, es incapaz de compensar completamente la falta de SMN1, debido a una transición de C a T en el exón 7. A pesar del progreso en el campo, el sitio celular de acción de la proteína SMN permanece incompleto. Definirlo completamente es crítico para los tratamientos clínicos y para mejorar nuestro conocimiento de la biología básica de la enfermedad. Estas preguntas se han abordado en gran parte a través del estudio de organismos modelo AME. Estos estudios han demostrado que la SMN es particularmente importante en las neuronas motoras; experimentos adicionales han explorado otros tejidos que también pueden ser particularmente sensibles a SMN, incluyendo el músculo esquelético. Sin embargo, el papel del músculo en SMA sigue siendo debatido y la función precisa de SMN en este tejido en lo que respecta a la patología de la enfermedad permanecen lejos de ser clara. Esto se debe en parte a que los experimentos in vivo realizados hasta la fecha no pueden descartar la posibilidad de que los cambios observados en el músculo estén simplemente ocurriendo como un efecto secundario de la denervación debido a la patología en las neuronas motoras innervantes. A medida que evolucionan las terapias para AME, éstas siguen siendo importantes cuestiones a responder. En consecuencia, el objetivo de este proyecto de investigación ha sido delimitar con mayor precisión el papel contributivo del músculo en la característica general de patología/fenotipo de AME. Nuestros resultados muestran que los niveles en estado natural de SMN en el músculo son absolutamente críticos para el mantenimiento del músculo sano. Por lo tanto, creemos que SMN funciones de células autónomas dentro de este tejido para garantizar su salud y viabilidad. Por lo tanto, se espera que la restauración de la proteína en el músculo constituya un aspecto vital del tratamiento de AME en las terapias de repleción de SMN.

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Cacho, Enio Walker Azevedo. « O efeito do treino de marcha com estimulação eletrica neuromuscular na atividade eletromiografica de pacientes paraplegicos ». [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313756.

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Orientador: Alberto Cliquet Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-04T03:56:05Z (GMT). No. of bitstreams: 1 Cacho_EnioWalkerAzevedo_M.pdf: 5346795 bytes, checksum: 6e74c1ae0171c8a520aa3738fe6e1bc4 (MD5) Previous issue date: 2004
Resumo: O efeito do treino de marcha através da estimulação elétrica neuromuscular (EENM) em pacientes com lesão da medula espinhal (LME) tem sido bem estabelecido. A medula espinhal humana reconhece apropriadas informações sensoriais e pode modular respostas motoras que facilitam a locomoção através do treinamento de marcha EENM assistido. Neste trabalho, dez pacientes (9 homens e uma mulher; 19 - 40 anos) com LME crônica (7 completas e 3 incompletas, nível neurológico abaixo de TI) foram avaliados no Laboratório de Biomecânica e Reabilitação do Aparelho Locomotor/Unicamp, no início e no fim de um programa de 30 sessões de treinamento de marcha assistido com EENM. Instrumentos utilizados para mensuração foram: American Spinal Injury Association (ASIA), Escala de Capacidade de Deambulação, Medida de Independência Funcional (MIF), Escala Modificada de Ashworth e o Registro Multicanais da Eletromiografia de superficie (EMG) dos músculos sóleos (SO), gastrocnêmios mediais (GA) e tibiais anteriores (TA) bilaterais. Os resultados demonstraram uma melhora do padrão EMG nos músculos GA e SO, durante a fase de apoio, e uma significante redução na fase de oscilação. A melhora no padrão EMG do TA ocorreu apenas à esquerda. Os resultados sugerem que o treino de marcha assistido com EENM pode induzir mudanças nos centros medulares espinhais
Abstract: The useful effect of locomotion training through neuromuscular electrical stimulation (NMES) in patients with spinal cord injury (SCI) has already been established. The human spinal cord recognizes the appropriate sensorial information and can modulate responses about the motor pool which facilitates walking under NMES training. In this series, ten patients (9 male and 1 female; 19 - 40 yrs-old) with chronic spinal cord injury (seven complete and three incompIete, neurologic leveI beIow T2) were evaluated at the Biomechanics & Rehabilitation Lab./University Hospital-Unicamp: first as soon as the patients joined the Programme and after 30 NMES based gait sessions. Clinical protocoIs of the American Spinal Injury Association (ASIA), Ability Ambulation Scale, Functional Independence Measure (FIM), Modified Ashworth Scale and the multichannel register surface of Electromyography (EMG) of muscIe soIeous (SO), gastrocnemious medialis (GA) and tibialis anterior (TA) were assessed. Results demonstrated an improvement in the EMG pattem of GA and TO muscles, during the stance phase and a significant decrease in the swing phase. Improvement in the EMG pattem in the TA muscle occurs just in the Ieft leg. Results suggest that gait training with NMES does induce changes in the spinal cord neural center, thus triggering the recovering of functional abilities/gait of paraplegics
Mestrado
Pesquisa Experimental
Mestre em Cirurgia

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Hendershot, Bradford Donald. « Alterations and Asymmetries in Trunk Mechanics and Neuromuscular Control among Persons with Lower-Limb Amputation : Exploring Potential Pathways of Low Back Pain ». Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/28668.

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Low back pain (LBP) is a substantial secondary disability among persons with lower-limb amputation (LLA). Abnormal mechanics of movement subsequent to LLA may increase the stability demands on the spinal column, and repetitive exposures to such abnormal movements may alter trunk passive properties and/or the coordination of surrounding trunk muscle responses. Further, preferential use of the sound limb may lead to asymmetries in these behaviors. Spine biomechanics (e.g., loading and stability) are substantially influenced by trunk passive properties and neuromuscular control, and alterations in these behaviors are associated with abnormal mechanics of the spinal column and an increased LBP risk. However, there is limited evidence regarding whether prolonged repeated exposures to abnormal gait and movement resulting from LLA and subsequent repeated use of a prosthetic device affect these trunk behaviors. Eight males with unilateral LLA and a matched sample of non-amputation controls completed three studies in which several measures of trunk passive properties, neuromuscular control, and spine biomechanics were quantified using laboratory experiments and biomechanical analyses. Each study involved a distinct task to investigate potential alterations and/or asymmetries in trunk passive properties and neuromuscular control. The first study used a seated balance task to assess trunk postural control and stability. The second study used multidirectional trunk perturbations to assess trunk mechanical and neuromuscular behaviors. Finally, the third study used controlled quasi-static trunk movements to assess load-sharing mechanisms between active and passive low back tissues. Significant alterations and asymmetries in trunk passive properties and trunk neuromuscular responses were present among participants with LLA, specifically reduced and asymmetric trunk stiffness and reflex response; decreased and asymmetric passive contributions to trunk movements; and increased trunk muscle activities. Significant increases in trunk postural sway and trunk muscle activities were also present during seated stability measures. Such alterations in these behaviors may be a result of repetitive exposures to abnormal gait and movement subsequent to LLA and the use of a prosthetic device, and could play a contributing role in the development of LBP in this population. Future work should investigate the temporal relationship between altered trunk behaviors and repeated exposure to abnormal gait and movement subsequent to LLA, to better identify critical years for rehabilitation and preventative care.
Ph. D.

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Nash, Leslie. « Exosomes : A Novel Biomarker and Approach to Gene Therapy for Spinal Muscular Atrophy ». Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38910.

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Spinal muscular atrophy (SMA) is a neuromuscular disease caused by reduced levels of the survival motor neuron (SMN) protein. SMA results in degeneration of motor neurons, progressive muscle atrophy, and death in severe forms of the disease. Currently, there is a lack of inexpensive, readily accessible, accurate biomarkers to study the disease. Furthermore, the current FDA approved therapeutic is neither 100 % effective nor accessible for all patients, thus more research is required. Tiny cell derived vesicles known as exosomes have been evaluated in an attempt to identify novel biomarkers for many disease states and have also shown therapeutic promise through their ability to deliver protein and nucleic acid to recipient cells. The research presented herein investigates whether (1) the level of SMN protein in exosomes isolated from the medium of cells, and serum from animal models and patients of SMA is indicative of disease, to serve as a biomarker for monitoring disease progression and therapeutic efficacy; (2) SMN-protein loaded exosomes can be utilized to deliver SMN protein to SMN-deficient cells; (3) adenoviral vectors are effective at creating SMN protein-loaded exosomes in situ for body wide distribution of SMN protein. This research has shown SMN protein is naturally released in extracellular vesicles, and the level of exosomal SMN protein is reflective of the disease state. Exosomes can also be modified to hold enhanced levels of SMN protein and deliver them to both the cytoplasm and nucleus of SMN-deficient cells. Furthermore, adenoviral vectors expressing luciferase-tagged SMN1 cDNA, targeted to the liver, results in SMN protein-loaded exosomes and detectable luciferase activity, body-wide. Thus, exosomes present as an effective biomarker and potentially a novel approach to treat SMA.

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Paolillo, Fernanda Rossi. « Efeitos da estimulação elétrica neuromuscular do quadríceps sobre as variáveis cardio-respiratórias em portadores de lesão medular ». Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-03122004-131558/.

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O objetivo desta pesquisa foi investigar as variáveis cardio-respiratórias (Pa, FC, 'VO IND.2', 'VCO IND.2' e Ve) durante a estimulação elétrica neuromuscular (EENM) do quadríceps em portadores de lesão medular. Participaram da pesquisa dez pacientes (cinco paraplégicos e cinco tetraplégicos) e um sujeito saudável voluntário padrão. O protocolo do teste consistiu em 10 minutos de repouso, 20 minutos de EENM dos quadríceps e 10 minutos de recuperação. O sujeito saudável realizou o mesmo procedimento, entretanto, os movimentos de flexão/extensão dos joelhos foram realizadas de maneira voluntária. Durante a EENM foram constatados baixos valores de 'VO IND.2' e 'VCO IND.2', lenta cinética dos gases e valores alterados de 'P IND.O2' e 'P IND.CO2', em outros casos foi constatada a rápida cinética dos gases. Houve o aumento da Pa sistólica e da FC, entretanto em alguns pacientes observaram-se limitações na resposta da FC. Portanto, os pacientes apresentaram algumas limitações nas respostas cardio-respiratórias, indicando realização de exercício exaustivo, mas apresentaram capacidade de realização de exercício induzido artificialmente, possivelmente devido aos benefícios da EENM
The objective of this research was to evaluate cardio-respiratory responses (heart rate, blood pressure, 'VO IND.2', 'VCO IND.2' e Ve) to neuromuscular electrical stimulation (NMES) of the quadriceps in patients with spinal cord injury. Ten patients (five paraplegics and five tetraplegics) and one healthy subject participated in this study. The protocol of the test consisted of ten minutes of rest, twenty minutes of NMES of the quadriceps and ten minutes of recovery. However, the healthy subject performed the voluntary movement of knee flexion and extension. The findings in this study indicated that patients during NMES demostrated low values of 'VO IND.2' e 'VCO IND.2', slow gas kinetics and altered values of 'P IND.O2' and 'P IND.CO2', on the others cases, the fast kinetics of the gas was verified. Moreover, there were increases in blood pressure and heart rate. Nevertheless, for some patients, heart rate response limitations were observed. Therefore, the patients presented some limitations in the cardio-respiratory responses, indicating performance of exhaustive exercise, but the use of NMES can elicit improvements in exercise tolerance due to its benefits

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Beck, Eddy Krueger. « Influência dos parâmetros estimulatórios na eficiência da contração muscular evocada pela estimulação elétrica funcional em pessoas hígidas ou com lesão medular ». Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/1045.

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CAPES
Introdução: A estimulação elétrica funcional (FES) é aplicada a pessoas portadoras de lesão medular (LM) com o objetivo de gerar movimentos funcionais artificialmente. A Mecanomiografia (MMG) mede a oscilação do músculo durante a contração. Os padrões estimulatórios são determinados pelos parâmetros: períodos on e off do pulso e do burst e suas amplitudes. Durante a sessão de aplicação da FES, o tecido neuromuscular responde de forma variada em decorrência de alterações fisiológicas como fadiga muscular e/ou adaptação do motoneurônio. Objetivo: na pesquisa desenvolvida, investigou-se a influência dos parâmetros estimulatórios na eficiência da contração muscular evocada pela FES em voluntários hígidos e portadores de lesão medular. Materiais e Métodos: participaram da pesquisa 10 voluntários hígidos (VHs) e 10 voluntários com LM (VLMs) com sensores de MMG posicionados sobre os ventres musculares dos músculos reto femoral e vasto lateral. Os estímulos elétricos foram aplicados sobre o nervo femoral para ativação do músculo quadríceps. Foram testados cinco padrões estimulatórios em dias diferentes, com oito contrações evocadas artificialmente e divididas em duas sessões com intervalo de 15 min entre elas. Resultados: foi proposto um índice de eficiência de FES com (1) o tempo de estimulação, (2) a menor variação angular e (3) a menor divergência dos descritores de MMG: frequência mediana (Median Frequency) e valor eficaz (Root Mean Square). Os padrões estimulatórios que apresentaram maior eficiência são os de 50 Hz para VHs e 70 Hz para VLMs, por manterem a contração evocada artificialmente por (1) maior tempo, com menor (2) variação angular e (3) resposta mecanomiográfica com menor alteração. Conclusões: conclui-se que os padrões estimulatórios empregando frequências de 50 Hz para VHs e de 70 Hz para VLMs foram mais eficientes na contração artificial por meio da FES.
Introduction: Functional electrical stimulation (FES) is applied to people with spinal cord injury (SCI) in order to artificially evoque functional movements. Mechanomyography (MMG) measures the oscillation of the muscle during contraction. The stimulatory profiles are controlled by the parameters: active and rest periods of the pulse and the burst and their amplitude. During the period of application of FES, the neuromuscular tissue responds in different ways, due to physiological changes such as muscle fatigue and/or adaptation of motor neurons. Objective: In the research developed, we investigated the influence of simulatory parameters on the efficiency of muscle contraction evoked by FES in healthy volunteers and patients with spinal cord injury. Materials and Methods: The healthy volunteers (HV) and ten subjects with SCI participated of the study. The MMG sensors were placed over the belly of the rectus femoris muscle and vastus lateralis. The electrical stimuli were yielded on the femoral nerve in order to activate quadriceps muscle. Five FES profiles were tested on different days with eight artificially evoked contractions divided into two sessions with an interval of fifteen minutes apart. Results: was proposed a FES efficiency index based on (1) stimulation time, (2) lower angular variation and (3) lower divergence of MMG descriptors: Median Frequency (MF) and Root Mean Square (RMS) value. FES profiles that showed better efficiency are: burst frequency of 50 Hz for HV and 70 Hz for SCI volunteers. They kept the contraction artificially evoked for (1) longer time, (2) lower angular variation of and (3) mechanomyographic response with minor modification. Conclusions: we conclude thar stimulatory profiles using frequencies of 50 Hz for HV and 70 Hz for SCI volunteers were more efficient for evoking contraction artificially.

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Castillo, Andrea Amaral. « Tônus muscular = uma contribuição para os estudos em imagem corporal ». [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275086.

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Orientador: Maria da Consolação Gomes Cunha Fernandes Tavares
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física
Made available in DSpace on 2018-08-18T10:27:09Z (GMT). No. of bitstreams: 1 Castillo_AndreaAmaral_M.pdf: 1424495 bytes, checksum: 2e616dc1accf2266891ba1011fc14c1e (MD5) Previous issue date: 2011
Resumo: A Imagem Corporal foi conceituada por Paul Schilder (1999) como a representação mental do corpo. Neste conceito ele aponta para uma abordagem sistêmica dos aspectos fisiológicos, psíquicos, sociais e culturais no processo dinâmico da expressão singular da identidade corporal. Em seu livro "The Image and appearance of humam body", publicado em 1935, Schilder chama a atenção para a relação entre o Tônus Muscular e a Imagem Corporal num capítulo exclusivo sobre o tema. Ressaltou que a Imagem Corporal era tracionada em direção ao Tônus Muscular uma vez que a ação de um único segmento corporal é capaz de colocar o corpo como um todo em uma nova relação com o ambiente. No entanto esta relação não se encontra sistematizada e valorizada dentro das diversas áreas do saber e tem sido pouco abordada nas pesquisas em Imagem Corporal. O foco direcionado ora ao Tônus Muscular, ora à Imagem Corporal implica muitas vezes num entendimento fragmentado capaz de desconsiderar a singularidade do indivíduo e/ou o dinamismo neurofisiológico na sua relação com o meio e com o outro. Assim a proposta deste estudo é sistematizar e analisar o conhecimento sobre o Tônus Muscular nas perspectivas de Charles Scott Sherrington cujo foco se apóia na Ação Reflexa; de Henry Head, que apresenta o Modelo Postural como a base para as pesquisas em Imagem Corporal; e da Neurociência, que propõe análises do comportamento humano na relação com o ambiente. Dentre as inúmeras contribuições feitas por Charles Scott Sherrington, foi a perspectiva da Ação Integrativa do sistema nervoso que trouxe um novo entendimento ao meio científico da época. Ao considerar a ação reflexa como uma resposta adaptativa do organismo, Sherrington encontrou no Tônus Muscular o exemplo explícito de um processo integrativo cuja proposta é manter a postura do organismo contra a gravidade. Henry Head influenciado por esse novo olhar, e inquieto com suas observações clínicas tornou-se o próprio objeto experimental numa investigação sobre os tipos de sensibilidade. A partir dos resultados de suas pesquisas e apoiado nas idéias e conceitos de Sherrington, Head propõe a existência de um Modelo Postural como uma medida de referência sobre a qual o corpo se ajusta constantemente através das variações do Tônus Muscular. Estas medidas são então registradas dentro de um esquema plástico de representação mental da postura e do movimento. A neurociência intensifica suas investigações sobre o organismo dentro do contexto do ambiente onde um é capaz de influenciar o outro. Com isso abriu-se uma nova perspectiva acerca do Tônus Muscular e o comportamento humano. As descobertas sobre a participação do fuso neuromuscular na elaboração da Imagem Corporal, as alterações mecânicas que implicam em alterações sensoriais e a ação segmentar que se propaga ao longo de todo o corpo trazem contribuições importantes que reforçam a relação íntima entre o Tônus Muscular e a representação mental do corpo. A partir deste estudo espera-se trazer uma reflexão mais profunda sobre o papel do Tônus Muscular e contribuir para futuras pesquisas e estudos sobre a Imagem Corporal
Abstract: Paul Schilder (1999) defined Body Image as the mental representation of the body. In this concept, he points out to a systemic approach of physiological, psychological, social and cultural aspects in the dynamic process of the body image unique expression. In his book "The Image and appearance of human body", published in 1935, Schilder draws attention to the relationship between Muscle Tonus and Body Image, dedicating a whole chapter to this theme. He emphasized that Body Image was pulled towards Muscle Tonus, since the action of a single body segment can place the whole body in a new interaction with the environment. However, this relationship has not been schematized and given the proper value by different areas of knowledge and it has been little addressed in studies about Body Image. Changing the focus from Muscle Tonus to Body Image back and forth can frequently lead to a fragmented understanding which may disregard each individual particularity and/or the neurophysiological dynamics in the individual interaction with the environment and others. Hence, this study aims to systematize and discuss the knowledge about muscle tone, as seen by Charles Scott Sherrington who focus on Reflex Action; by Henry Head, who presents Postural Model as fundamental for Body Image researches; and by Neuroscience, which suggests the study of human behavior and its relation with the environment. One of the several contributions by Charles Scott Sherrington, the Integrative Action of the nervous system brought a new understanding to the scientific community at the time. By considering reflex action as an adjustable response of the body, Sherrington saw the Muscle Tonus as a clear example of an integrative process which aims to keep the body posture against gravity. Henry Head was influenced by this new approach, and, out of a strong urge towards his clinical observation, became his own experiment subject on his study about sensitivity types. Supported by the results of his own researches and backed by Sherrington's concepts and ideas, Head suggests that there is a Postural Model acting as a reference measure which the body constantly fits into according to Muscle Tonus variations. These measures are registered within a scheme of posture and movement representations. Neuroscience stresses the focus of studies about the body within a context where one causes an impact on the other, bringing out a new outlook for Muscle Tone and human behavior. Findings about neuromuscular fuse participation in Body Image building, mechanical changes which cause sensorial changes and the segmental action which spreads throughout the body play an important role and corroborate the close relationship between Muscle Tonus and body mental representation. This study is expected to bring up a more comprehensive discussion on the role of Muscle Tonus and to enhance future researches and studies on Body Image
Mestrado
Atividade Fisica Adaptada
Mestre em Educação Física

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Takeno, Katsumi. « Neuromuscular Function of the Shoulder Girdle and Upper Extremity Muscles in Individuals with Glenohumeral Labral Repair ». University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1596111099423871.

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Krueger, Eddy. « Detecção de fadiga neuromuscular em pessoas com lesão medular completa utilizando transformada wavelet ». Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/961.

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CNPq
Introdução: As pessoas com lesão medular (LM) podem ter seus músculos paralisados ativados por meio da estimulação elétrica funcional (FES) sobre vias neurais presentes próximas à pele. Estas estimulações elétricas são importantes para a recuperação do trofismo neuromuscular ou durante o controle de movimento por próteses neurais. No entanto, ao longo da aplicação da FES, a fadiga ocorre, diminuindo a eficiência da contração, principalmente devido à hipotrofia neuromuscular presente nessa população. A aquisição da vibração das fibras musculares como indicador de fadiga é registrada por meio da técnica de mecanomiografia (MMG), que não sofre interferências elétricas decorrentes da aplicação da FES. Objetivo: Caracterizar a vibração do músculo reto femoral durante protocolo de fadiga neuromuscular eletricamente evocada em pessoas com lesão medular completa. Método: 24 membros (direito e esquerdo) de 15 participantes (idade: 27±5 anos) do sexo masculino (A e B na American Spinal Injury Impairment Scale) foram selecionados. Um estimulador elétrico operando como fonte de tensão, desenvolvido especialmente para pesquisa, foi configurado com: freqüência de pulso em 1 kHz (20% de ciclo de trabalho) e trem de pulsos (modulação) em 70 Hz (20% período ativo). O sinal triaxial [X (transversal), Y (longitudinal) e Z (perpendicular)] da MMG foi processado com filtro Butterworth de terceira ordem e banda passante entre 5 e 50 Hz. Previamente ao protocolo, a tensão de saída do estimulador foi incrementada (~3 V/s evitando-se a adaptação/habituação dos motoneurônios) até alcançar a extensão máxima eletricamente estimulada (EMEE) da articulação do joelho. Uma célula de carga foi usada para registrar a resposta de força, onde após a sua colocação, a intensidade da FES necessária para alcançar a EMEE foi aplicada e registrada pela célula de carga como 100% da força (F100%). Durante o protocolo de fadiga neuromuscular, a intensidade do estímulo foi incrementada durante o controle para manter a força em F100%. Quatro instantes (I - IV) foram selecionados entre F100% e a incapacidade da FES manter a resposta de força acima de 30% (F30%). O sinal foi processado nos domínios temporal (energia), espectral (frequência mediana) e wavelet (temporal-espectral com doze bandas de frequência entre 5 e 53 Hz). Os dados extraídos foram normalizados pelo instante inicial (I) gerando unidades arbitrárias (u.a.), e testados com estatística não paramétrica. Resultados: A frequência mediana não apresentou significância estatística. Em relação aos eixos de deslocamento da MMG, o eixo transversal mostrou o maior número de resultados estatisticamente significantivos. A energia da vibração das fibras musculares (domínio temporal) indicou diminuição entre os instantes I (músculo fresco) e II (pré-fadiga), como também entre os instantes I e IV (fadigado) com redução significativa. O domínio wavelet teve como foco o eixo transversal, especialmente as bandas de frequência de 13, 16, 20, 25 e 35 Hz, por terem indicado redução significativa durante a fadiga neuromuscular; principalmente, a banda de 25 Hz, que indicou redução significativa entre o instante I (valor da mediana dos dados de 0,53 u.a.) e os demais instantes [II (0,30 u.a), III (0,28 u.a.) e IV (0,24 u.a.)]. Conclusão: A fadiga neuromuscular é caracterizada pela redução da energia do sinal no eixo de deslocamento transversal (X) da vibração do músculo reto femoral, em pessoas com lesão medular completa, tanto no domínio temporal quanto principalmente no domínio wavelet, sendo a banda de frequência de 25 Hz a mais relevante, porque sua energia diminui com a ocorrência da fadiga neuromuscular. Estes achados abrem a possibilidade de aplicação em sistemas de malha fechada durante procedimentos de reabilitação física utilizando FES ou no controle de próteses neurais.
Introduction: People with spinal cord injury (SCI) may have the paralyzed muscles activated through functional electrical stimulation (FES) on neural pathways present below the skin. These electrical stimulations are important to restore the neuromuscular trophism or during the movement control using neural prostheses. However, prolonged FES application causes fatigue, which decreases the contraction strength, mainly due the neuromuscular hypotrophy in this population. The acquisition of myofibers’ vibration is recognized by mechanomyography (MMG) system and does not suffer electrical interference from the FES system. Objective: To characterize the rectus femoris muscle vibration during electrically evoked neuromuscular fatigue protocol in complete spinal cord injury subjects. Methods: As sample, 24 limbs (right and left) from 15 male participants (age: 27±5 y.o.) and ranked as A and B according to American Spinal Injury Impairment Scale) were selected. An electrical stimulator operating as voltage source, specially developed for research, was configured as: pulse frequency set to 1 kHz (20% duty cycle) and burst (modulating) frequency set to 70 Hz (20% active period). The triaxial [X (transverse), Y (longitudinal) and Z (perpendicular)] MMG signal of rectus femoris muscle was processed with a third-order 5-50 Hz bandpass Butterworth filter. A load cell was used to register the force. The stimulator output voltage was increased (~3 V/s to avoid motoneuron adaptation/habituation) until the maximal electrically-evoked extension (MEEE) of the knee joint. After the load cell placement, the stimuli magnitude required to reach MEEE was applied and registered by the load cell as muscular F100% response. Stimuli intensity was increased during the control to keep the force in F100%. Four instants (I - IV) were selected from F100% up to the inability to keep the FES response force above 30% (F30%). The signal was processed in temporal (energy), spectral (median frequency) and wavelet (temporal-spectral with twelve band frequencies between 5 and 53 Hz) domains. All data were normalized by initial instant, creating arbitrary units (a.u.), and non-parametric tests were applied. Results: The median frequency did not show statistical significance. Regarding the MMG axes, the transverse axis showed most statistical differences. The MMG energy (temporal domain) indicates the decrease between the instants I (unfatigued) and II (pre-fatigue), as well as instants I and IV (fatigued). The wavelet domain focused on the transverse axis, especially on 13, 16, 20, 25 and 35 Hz frequency bands, for having shown significant reduction proven during neuromuscular fatigue. In focus on 25 Hz band frequency that showed a constant decrease between instants I (median value from data de 0.53 a.u.) with subsequent instants [II (0.30 a.u.), III (0.28 a.u.) and IV (0.24 a.u.). Conclusion: Neuromuscular fatigue is characterized by energy decrease in MMG X-axis (transverse) signal of vibration on the rectus femoris muscle for complete spinal cord injured subjects, in the temporal domain but mainly in the wavelet domain. The 25 Hz is the most important band frequency because its energy decreases with neuromuscular fatigue. These findings open the possibility of application in closed-loop systems during physical rehabilitation procedures using FES or in the control of neural prostheses.

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Bunderson, Nathan Eric. « Role of heterogenic spinal reflexes in coordinating and stabilizing a model feline hindlimb ». Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22634.

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Thesis (Ph. D.)--Biomedical Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Thomas J. Burkholder; Committee Member: Lena H. Ting; Committee Member: Roman O. Grigoriev; Committee Member: Shawn Hochman; Committee Member: T. Richard Nichols.

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Sleigh, James Nicholas. « Model systems for exploring new therapeutic interventions and disease mechanisms in spinal muscular atrophies (SMAs) ». Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:378416c5-a586-4a2a-980c-81dfff6803df.

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Spinal muscular atrophy (SMA) and Charcot-Marie-Tooth disease type 2D (CMT2D)/distal SMA type V (dSMAV) are two incurable neuromuscular disorders that predominantly manifest during childhood and adolescence. Both conditions are caused by mutations in widely and constitutively expressed genes that encode proteins with essential housekeeping functions, yet display specific lower motor neuron pathology. SMA results from recessive inactivating mutations in the survival motor neuron 1 (SMN1) gene, while CMT2D/dSMAV manifests due to dominant point mutations in the glycyl-tRNA synthetase (GlyRS) gene, GARS. Using a number of different model systems, ranging from Caenorhabditis elegans to the mouse, this thesis aimed to identify potential novel therapeutic compounds for SMA, and to increase our understanding of the mechanisms underlying both diseases. I characterised a novel C. elegans allele, which possesses a point mutation in the worm SMN1 orthologue, smn-1, and showed its potential for large-scale screening by highlighting 4-aminopyridine in a screen for compounds able to improve the mutant motility defect. Previously, the gene encoding three isoforms of chondrolectin (Chodl) was shown to be alternatively spliced in the spinal cord of SMA mice before disease onset. I performed functional analyses of the three isoforms in neuronal cells with experimentally reduced Smn levels, and determined that the dysregulation of Chodl likely reflects a combination of compensatory mechanism and contributor to pathology, rather than mis-splicing. Finally, working with two Gars mutant mice and a new Drosophila model, I have implicated semaphorin-plexin pathways and axonal guidance in the GlyRS toxic gain-of-function disease mechanism of CMT2D/dSMAV.

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Cowan, Kirsten. « The Effect of Two Surgeons on Operative Time, Anesthesia Time, and Blood Loss in Pediatric Patients with Neuromuscular Scoliosis Undergoing Posterior Spinal Fusion Surgery ». Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/315824.

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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.
Objective The goal of this study was to investigate the effect of using a two attending surgeon approach on operative time, anesthesia time, and estimated blood loss in patients with neuromuscular scoliosis undergoing posterior spinal fusion surgery. Methods This was a retrospective chart review study of patients with neuromuscular scoliosis who underwent posterior spinal fusion surgery at Phoenix Children’s Hospital in 2011 and 2012. Results Results from 70 patients showed a significant reduction in operative and anesthesia times for patients with two attending surgeons as opposed to one. Mean operative time for the two surgeon group was 3 hours 30 minutes (SD = 49 minutes) and was significantly shorter than 4 hours 26 minutes (SD = 1 hour 22 minutes), the mean operative time for the one surgeon group, t (56) =3.44, p = .001. Mean anesthesia time for the two surgeon group was 5 hours 28 minutes (SD = 55 minutes) and was significantly shorter than 6 hours 9 minutes (SD = 1 hour 28 minutes), the mean anesthesia time for the one surgeon group, t (57) = -2.34, p = .023. There was no significant difference in estimated blood loss found between the groups. The mean blood loss for the two surgeon group was 1202.1 ml( SD = 1033.1) versus 1042.1 ml (SD = 959.41) for the one surgeon group, t(68) = .671, p = .50. This pattern of results remained the same in subgroup analysis designed to compare cases with similar severity of presentation. Significance Patients with neuromuscular scoliosis may benefit from a two attending surgeon approach to posterior spinal fusion. More studies are needed to determine modifiable risk factors for excessive blood loss in neuromuscular scoliosis patients as well as to investigate the effect of using a two surgeon approach on specific post-operative complications.

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Cerveró, Cebrià Clàudia. « Atròfia muscular espinal : mecanismes patogènics i estratègies terapèutiques en models murins de la malaltia ». Doctoral thesis, Universitat de Lleida, 2016. http://hdl.handle.net/10803/399028.

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L’atròfia muscular espinal (AME) és una malaltia genètica que cursa amb mort de motoneurones espinals i atròfia muscular. S’ha caracteritzat un model murí d’AME, l’Smn2B/-, amb una clínica menys severa que la mostrada per altres models més extensament utilitzats. S’ha evidenciat una alteració multisistèmica acompanyant a la clàssicament coneguda del sistema neuromuscular. S’han estudiat les sinapsis colinèrgiques tipus C en l’AME i testat el paper del PRE-084 (agonista del receptor sigma-1 present en aquestes) com a possible teràpia en els models SMNΔ7 i Smn2B/-. Malgrat no conferir neuroprotecció, el PRE-084 ha evitat la gliosi pròpia de l’AME. Finalment, s’ha testat l’efectivitat de l’AICAR, agent mimètic de l’exercici físic, en ratolins SMNΔ7. L’AICAR ha mitigat l’atròfia muscular, els defectes estructurals en les unions neuromusculars i la pèrdua de sinapsis glutamatèrgiques en el soma de les motoneurones, però no ha evitat la mort neuronal ni la reacció glial en la medul·la espinal.
La atrofia muscular espinal (AME) es una enfermedad genética que cursa con muerte de motoneuronas espinales y atrofia muscular. Se ha caracterizado un modelo murino de AME, el Smn2B/-, con una clínica menos severa que la mostrada por otros modelos más extensamente utilizados. Se ha evidenciado una alteración multisistémica acompañando a la clásicamente conocida del sistema neuromuscular. Se han estudiado las sinapsis colinérgicas de tipo C en la AME y testado el papel del PRE-084 (agonista del receptor sigma-1 presente en estas) como posible terapia en los modelos SMNΔ7 y Smn2B/-. A pesar de no conferir neuroprotección, el PRE-084 ha evitado la gliosis propia de la AME. Finalmente, se ha testado la efectividad del AICAR, agente mimético del ejercicio físico, en ratones SMNΔ7. El AICAR ha mitigado la atrofia muscular, los defectos estructurales en las uniones neuromusculares y la pérdida de sinapsis glutamatérgicas en el soma de las motoneuronas, pero no ha evitado la muerte neuronal ni la reacción glial en la medula espinal.
The spinal muscular atrophy (SMA) is a genetic disease that affects spinal motor neurons causing its death and muscle atrophy. This study is divided in three parts. First. Characterization of the Smn2B/- mice, a mild SMA phenotype model. A multisistemic affectation was reported to accompany the better known neuromuscular alteration in these mice. Second. Study of C-type cholinergic synapses in the SMA and therapeutic trial with the sigma-1 receptor agonist PRE-084 (molecule present in C boutons) in the SMNΔ7 and Smn2B/- mice. Although PRE-084 did not confer neuroprotection, it prevented the SMA characteristic reactive gliosis. Third. Treatment with AICAR, an exercise mimetic agent, in SMNΔ7 mice. AICAR mitigated muscular atrophy and structural defects in neuromuscular junctions and prevented loss of glutamatergic synapses in the motoneuron soma but it did not protect against neuronal death and reactive gliosis.

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Ilha, Jocemar. « Reabilitação e plasticidade neuromuscular após lesão medular : efeitos do treino de marcha em esteira e transplante de glia embainhante olfatória ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/31789.

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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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Varoto, Renato. « Desenvolvimento e avaliação de um protótipo de sistema híbrido para membro superior de tetraplégicos ». Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-09062010-100922/.

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Em geral, indivíduos com disfunções motoras nos membros superiores apresentam dificuldades para executar a movimentação de objetos, a qual é essencial para a execução das atividades de vida diária. Dessa forma, esses indivíduos não a executam ou a fazem de maneira ineficiente. Para que essa manipulação seja realizada de maneira satisfatória, fazem-se necessários os movimentos de alcance e preensão de objetos controlados voluntariamente pelo indivíduo, e também a aquisição sensorial da força empregada durante a preensão. Portanto, este trabalho apresenta o desenvolvimento, a aplicação e a avaliação de um protótipo de sistema híbrido visando à reabilitação parcial da capacidade sensório-motora do membro superior direito de tetraplégicos. Tal sistema engloba uma órtese dinâmica para cotovelo utilizada em conjunto com a estimulação elétrica neuromuscular, e uma luva instrumentada que possibilita a realimentação qualitativa da força de preensão. Os resultados das avaliações clínicas mostraram que o sistema auxilia os tetraplégicos em tarefas que envolvem o alcance e a preensão de objetos, bem como trazê-los para próximo do corpo. O aumento da faixa de alcance, a geração de preensão e a restauração artificial da habilidade de movimentar um objeto para próximo do corpo representam esse auxílio proporcionado pelo sistema. Assim o protótipo de sistema híbrido representa uma estratégia alternativa para a reabilitação de lesados medulares (níveis C5-C6).
Generally, individuals with motor impairments in the upper limbs have difficulties performing the movement of objects, which is essential for the execution of activities of daily living. Thus, these individuals do not perform these activities or perform them inefficiently. Toward satisfactory manipulation, reach and grasp movements of objects performed with voluntary control, and grasp force feedback are necessary. Therefore, this work presents the development, application and evaluation of a hybrid system prototype aiming at partial rehabilitation of sensory-motor ability of quadriplegic\'s right upper limb. Such system includes an elbow dynamic orthosis combined with neuromuscular electrical stimulation, and an instrumented glove that allows the qualitative grasp force feedback. The results of clinical assessment showed that the system aids quadriplegic in tasks that involve reaching and grasping of objects, as well as bringing them close to the body. The improvement of reaching range, grasping generation and artificial restoration of the ability to move an object close to the body represent this aid provided by the system. Thus, the hybrid system prototype represents an alternative strategy for the rehabilitation of individuals with spinal cord injury (C5-C6 level).

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Dambreville, Charline. « Compensation neuromusculaire lors de la locomotion suite à une dénervation de deux extenseurs de la cheville chez le chat adulte spinalisé ». Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8780.

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Résumé : Le muscle squelettique étant d’une grande plasticité, il peut être la cible lors de thérapies en réhabilitation motrice. Toutefois, les structures neurales impliquées dans cette plasticité sont encore peu connues. Afin de déterminer si un mécanisme spinal est suffisant pour induire une plasticité musculaire, le nerf innervant le gastrocnémien latéral et le soleus a été sectionné unilatéralement chez 4 chats ayant retrouvé une locomotion au niveau des pattes arrières suite à une spinalisation complète. Des enregistrements électromyographiques et cinématiques ont été enregistrés avant et jusque 8 semaines après dénervation chez ces chats. Des analyses histologiques ont été réalisées pour les deux gastrocnémiens médial et latéral chez les 4 chats spinalisés et chez 4 chats intacts servant de contrôle. Chez les chats spinaux, la durée de cycle pour la patte ispilatérale et controlatérale à la dénervation pouvait être diminuée ou augmentée par rapport aux valeurs de pré-dénervation. Pour la durée de la phase d’appui, elle était généralement augmentée pour la patte controlatérale et diminuée pour la patte ipsilatérale. L’amplitude EMG du MG était augmentée bilatéralement après la dénervation et est restée élevée 8 semaines post dénervation. Concernant le poids des muscles, chez les chats spinaux, le LG ipsilatéral était significativement plus petit que le LG controlatéral alors que le MG ipsilatéral était plus gros que le MG controlatéral. Les analyses histologiques ont montré une plus grande aire pour les fibres de type IIa pour le MG ipsilatéral pour 3 des 4 chats. La densité de capillaires sanguins dans le MG ipsilatéral était aussi plus élevée que dans le MG controlatéral. Pour les chats intacts, aucune différence n’a été observée pour le poids, l’aire des fibres ou la densité capillaire entre les 2 MG. Ces résultats montrent que le muscle squelettique peut s’adapter même après une lésion de la moelle épinière, ce qui souligne l’importance de son utilisation en réhabilitation motrice.
Abstract : Skeletal muscle is highly plastic and can be targeted for motor rehabilitation. Although neural activity potently regulates muscle phenotype, the neural structures required are poorly defined. To determine if a spinal mechanism is sufficient for adaptive muscle plasticity, the nerve supplying the lateral gastrocnemius and soleus muscles was sectioned unilaterally in four cats that had recovered hindlimb locomotion following spinal transection. In these spinal cats, kinematics and electromyography (EMG) were collected before and for 8 weeks after denervation. Muscle histology was performed on the lateral (LG) and medial (MG) gastrocnemii bilaterally in four spinal and four intact cats. In spinal cats, cycle duration for the hindlimb ipsilateral or contralateral to the denervation could be increased or decreased compared to pre-denervation values. Stance duration was generally increased and decreased for the contralateral and ipsilateral hindlimbs, respectively. The EMG amplitude of MG was increased bilaterally following denervation and remained elevated 8 weeks post-denervation. In spinal cats, the ipsilateral LG was significantly smaller than the contralateral LG whereas the ipsilateral MG weighed significantly more than the contralateral MG. Histological characterizations revealed significantly larger fiber areas for Type IIa fibers of the ipsilateral MG in three of four spinal cats. Microvascular density in the ipsilateral MG was significantly higher than the contralateral MG. In intact cats, no differences were found for muscle weight, fiber area or microvascular density between homologous muscles. Results show that skeletal muscle remains remarkably adaptable after complete spinal cord injury, highlighting its importance to maximize force production in motor rehabilitation.

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Bochkezanian, Vanesa. « Effect of a neuromuscular electrical stimulation muscle strength training intervention on muscle force and mass, physical health and quality of life in people with spinal cord injury ». Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2017. https://ro.ecu.edu.au/theses/1994.

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Spinal cord injury (SCI) leads to significant deficits in muscle strength and mass, impacting negatively on physical health and quality of life (QoL). Physical rehabilitation techniques for people with SCI rely on constant updates and the accumulation of evidence regarding the efficacy of available and/or new physical interventions. Neuromuscular electrical stimulation (NMES) is already commonly used to activate skeletal muscles and subsequently reverse muscle atrophy, however NMES as a high-intensity “strength training” intervention appears to be a particularly promising technique for increasing muscle strength and mass and to subsequently improve physical health and quality of life (QoL) in people with SCI. Nonetheless, there are many factors limiting the use of standard NMES protocols, and further evidence pertaining to the use of high-intensity NMES strength training in clinical populations is warranted. The primary aim of the research described in this thesis was to examine the effects of NMES as a high-intensity muscle strength training intervention, specifically using wide-pulse width (1000 μs), low-to-moderate frequency (30 Hz) NMES combined with tendon vibration, on muscle strength and mass, physical health, symptoms of spasticity and QoL in people with SCI. This thesis includes two cross-sectional studies examining the effects of patellar tendon vibration (55 Hz, 7 mm amplitude) superimposed onto wide-pulse width (1000 μs) NMES (e.g. 30 Hz over 2 s) on the peak muscular (knee extensor) force and total impulse elicited by, and rate of recovery from, the intervention in healthy subjects (Study 1) and in people with chronic SCI (Study 2). The results of Study 1 revealed that superimposing tendon vibration onto wide-pulse width NMES leads to an increase in the muscle work performed before fatigue in only some individuals (i.e. positive responders, 50% of individuals in the current study), but decreases it in others (i.e. negative responders). However, it tends to reduce the voluntary force loss that was consistently experienced after a training session using high-intensity NMES, and may thus allow for additional exercise or rehabilitation work to be performed without ongoing voluntary muscle fatigue in healthy people. The results of Study 2 also identified positive and negative responders to tendon vibration in people with SCI, however the responses were less clear and a defined effect of tendon vibration superimposed onto NMES was not discerned. In Study 3, a 12-week (twice-weekly) high-intensity NMES strength training intervention was implemented in people with chronic SCI; based on results of Study 2, high-force contractions were evoked by NMES without superimposed tendon vibration. A significant increase in muscle mass (45%) and strength (tetanic evoked force; 31.8%), amelioration of spasticity symptoms, and improvement in some aspects of physical health and QoL were observed. Therefore, the use of high-intensity NMES strength training appears to be an effective rehabilitation tool to increase muscle force and mass, ameliorate symptoms of spasticity and improve physical and mental health outcomes in people with SCI.

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Mesquita, Marceli Matos Andrade. « Avaliação da força dos músculos do tronco em idosas : reprodutibilidade, associação com o desempenho funcional e efeitos dos treinamentos funcional e tradicional ». Pós-Graduação em Educação Física, 2018. http://ri.ufs.br/jspui/handle/riufs/9144.

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The maintenance of the trunk muscles strength presents great importance in the elderly’s health, since it is related to a better performance during the daily activities. However, scientific literature limitations are found when analyzing the tests to measure the strength of these muscles and, in addition, the importance of these muscles in functional performance in the elderly people is not clear. Therefore, the objective of this dissertation was: I) to evaluate the reproducibility of the maximal isometric trunk strength test in the elderly women; II) to verify the association between strength and endurance in the trunk muscles on measures of functional performance in elderly women; and III) to analyze the effects of functional and traditional training on maximal isometric strength and endurance in elderly women. Study I verified the reproducibility of the maximal strength test of the trunk muscles in the elderly, in two days of evaluations, through Interclass Correlation Coefficient, Coefficient of Variation, Minimum Detectable Change, Standard Error of Measure, as well as graphical analysis of Bland-Altman. The study results showed high to very high interclass correlation (extensors = 0.93, flexors = 0.86, respectively); low variation (9% for both muscle groups); and minimal detectable change acceptable (extensors = 51.1 N, flexors = 48.9 N). Furthermore, the Bland-Altman analysis reveals low bias and values within the limits of agreement. In study II, a multiple linear regression was performed with the purpose of explaining to what magnitude the strength and endurance of the trunk muscles contribute to functional performance in elderly women. Thus, there was a participation of the trunk extensor muscles endurance that ranged from 17.9% to 24.4% in functional performance in the elderly. In study III, a randomized and controlled clinical trial was conducted with three groups: functional training, traditional training and control group. The intervention groups performed a training with functional and progressive characteristics, so that the traditional training group performed the exercises in analytical machines and the functional training group, exercises with characteristics of movement patterns in a multiplanar and coordinated manner, incorporating multiple joints. The groups were evaluated before and after 12 training weeks through trunk muscles maximal strength test. After 12 training weeks, it was verified that the functional training group obtained a statistically significant improvement for all variables analyzed: maximum strength test, trunk extensor and flexor muscles strength and endurance ratio. The traditional training group was superior only in the variable of trunk extensor muscles strength development rate. Accordingly, it is concluded that the trunk muscles maximal strength test in elderly women presents high reproducibility; there is a great association between the trunk muscles endurance in the functional performance and the functional training seems more effective than the traditional training in relation to the increase of the trunk muscles maximal strength and endurance, in addition to the rate of trunk flexor muscles strength development.
A manutenção da força dos músculos do tronco apresenta grande importância na saúde em idosos, uma vez que está relacionada com um melhor desempenho durante as atividades de vida diária. Entretanto, limitações são encontradas na literatura científica ao analisar os testes para mensurar a força desses músculos e, além disso, não está clara a importância desses músculos no desempenho funcional em idosos. Diante disso, o objetivo desta dissertação foi: I) avaliar a reprodutibilidade do teste de força isométrica máxima do tronco em idosas; II) verificar a associação entre a força e a endurance do tronco sobre as medidas de desempenho funcional em idosas; e III) analisar os efeitos dos treinamentos funcional e tradicional sobre a força isométrica máxima e a endurance do tronco em idosas. O estudo I verificou a reprodutibilidade do teste de força máxima dos músculos do tronco em idosas em dois dias de avaliações, através do Coeficiente de Correlação Interclasse, do Coeficiente de Variação, da Mínima Mudança Detectável, do Erro Padrão de Medida e também da análise gráfica de Bland-Altman. Os achados desse estudo revelaram correlação interclasse alta a muita alta (extensores=0,93; flexores=0,86, respectivamente); baixa variação (9% para os dois grupos musculares); e mínima mudança detectável aceitável (extensores=51,1 N; flexores=48,9 N). Além disso, a análise de Bland-Altman revela baixo viés e valores dentro dos limites de concordância. No estudo II, foi realizada uma regressão linear múltipla com o intuito de explicar em que magnitude a força e a endurance dos músculos do tronco contribuem no desempenho funcional em idosas. Dessa forma, houve uma participação da endurance dos músculos extensores do tronco, que variou entre 17,9% a 24,4% no desempenho funcional em idosas. Já no estudo III, foi realizado um ensaio clínico randomizado e controlado com três grupos: treinamento funcional, treinamento tradicional e grupo controle. Os grupos de intervenção realizaram um treinamento com características funcional e progressiva, de forma que o grupo treinamento tradicional realizou os exercícios em máquinas analíticas e o grupo treinamento funcional, exercícios com características de padrões de movimentos de maneira multiplanar e coordenada, incorporando múltiplas articulações. Aplicadas 12 semanas de treinamento, foi constatado que o grupo treinamento funcional obteve melhora significativa para todas as variáveis analisadas: teste de força máxima, taxa de desenvolvimento de força e endurance dos músculos extensores e flexores do tronco. O grupo treinamento tradicional foi superior apenas na variável de taxa de desenvolvimento de força dos músculos extensores do tronco. Assim, conclui-se que o teste de força máxima para os músculos do tronco em idosas apresenta alta reprodutibilidade; há associações entre a endurance dos músculos do tronco e desempenho funcional, e o treinamento funcional parece mais eficaz que o treinamento tradicional em relação ao aumento de força máxima e endurance dos músculos do tronco, além da taxa de desenvolvimento de força dos músculos flexores do tronco.
São Cristóvão, SE

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Buhmann, Robert Lee. « Potential mechanisms contributing to deficiencies in voluntary activation associated with hamstring strain injury ». Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/180911/2/Robert_Buhmann_Thesis.pdf.

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Recent evidence suggests an inability of those with a prior hamstring strain injury to fully voluntarily activate the previously injured muscle. This may limit gains in strength and muscle fibre length during rehabilitation, both of which are linked to increased risk of injury. Understanding the mechanisms contributing to voluntary activation deficits may assist in developing effective rehabilitation strategies and consequently limiting re-injury risk. The aim of this body of work was to determine the site(s) of failure within the nervous system underpinning lower levels of voluntary activation in participants with prior hamstring injury.

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Navalgund, Anand Rangnath. « Evaluating The Effect Of A 10-Week Stabilization Exercise Program On The Postural Stability And The Neuromuscular Control Of The Spine In Subjects With Subacute Recurrent Low Back Pain ». The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1261496801.

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Lepley, Adam Scott. « Examining Neural Alterations as the Origins of Disability in Patients Following Anterior Cruciate Ligament Reconstruction ». University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1393412488.

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Ortolan, Rodrigo Lício. « Esforço do ombro na locomoção de pacientes paraplégicos : avaliação cinética e eletromiográfica ». Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-17122009-105730/.

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Pacientes lesados medulares frequentemente mencionam dores nos ombros, devido à elevada demanda dos membros superiores. Estes pacientes se submetem a diferentes tipos de reabilitação, no entanto é importante avaliar os métodos utilizados em tais programas para evitar possíveis prejuízos. O objetivo deste trabalho é avaliar o esforço e a atividade muscular dos ombros em pacientes paraplégicos caminhando com Estimulação Elétrica Neuro Muscular (EENM) e um andador em seções de reabilitação e comparar com duas atividades diárias executadas por estes indivíduos: propulsão da cadeira de rodas e elevação para alívio da pressão. Quinze homens adultos com paraplegia foram avaliados. Os movimentos em 3 dimensões foram obtidos com um sistema de 6 câmeras de infravermelho, e a atividade mioelétrica de 6 músculos dos ombros foi obtida bilateralmente por eletrodos de superfície ativos. Um andador instrumentalizado capturou a força durante a marcha, e a força nas outras duas atividades foi obtida por dinâmica inversa utilizando os dados cinemáticos e antropométricos. Os dados cinéticos e da atividade muscular foram avaliados estatisticamente utilizando análise de variância (ANOVA) e o teste das diferenças menos significativas de Tukey com nível de significância p<0,05. Foram obtidos picos de força quatro vezes maiores durante a marcha comparando-se à propulsão da cadeira de rodas. O esforço do ombro durante a marcha e a elevação foi equivalente, porém o lado direito durante a marcha apresentou maiores valores. O músculo mais ativo durante a marcha foi o tríceps, seguido pelo peitoral maior, deltóide anterior e trapézio inferior. A ação geral dos músculos durante a marcha também foi maior comparada aos outros exercícios executados. A marcha com EENM e andador, realizada por lesados medulares durante as seções de reabilitação, requer esforços significativos dos membros superiores, podendo gerar complicações nas articulações do ombro. Lesados medulares submetidos a seções de reabilitação que executam esforços significativos devem ser frequentemente monitorados, por métodos de ultra-som ou ressonância magnética, para evitar o comprometimento dos membros superiores e a consequente perda das funções de independência remanescentes
Spinal Cord Injured subjects often refer pain in their shoulders, due to the increased demand of the upper limbs. These subjects usually go through different rehabilitation strategies. Therefore, it becomes rather important to assess those methods in order to avoid further injuries to the patients. The goal of this work was to evaluate the shoulder effort and muscular activity in paraplegic subjects during gait with Neuromuscular Electrical Stimulation (NMES) with the aid of a walker and to compare it with two daily activities: wheelchair start up and weight relief raise. Fifteen adult male paraplegics were part of this study. The three-dimensional motions were acquired with six infrared cameras, and surface-active electrodes recorded the electromyography activity of 6 shoulder muscles, bilaterally. The vertical reaction force during walking was measured with a strain gauge instrumented walker, and the horizontal (wheelchair start-up) and vertical (weight relief raise) forces were obtained by inverse dynamics from kinematics and anthropometric data. The statistics of kinetic and electromyography data were done by analysis of variance (ANOVA) and the Tukey least significant differences post hoc test with significance level of p<0,05. Results have shown NMES gait force peaks being about four times higher than the values obtained for wheelchair start-up. The shoulder effort (force and torque) during walking and weight relief was similar, although the right side during NMES gait presented greater values. The triceps was the most active muscle during NMES walking, followed by pectoralis major, anterior deltoid and lower trapezius. The overall muscular activity during NMES walking was again higher than the other tasks executed. The NMES walking, when performed by spinal cord injured subjects can lead to injuries to the shoulder girdle. Due to the results obtained, continuous supervision of paraplegic upper limb effort should therefore be part of any rehabilitation center and for that ultrasound or magnetic resonance imaging may be recommended

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