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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

A contribuição da análise eletromiográfica de superfície para a definição da fase de evolução da paralisia facial periférica: fase flácida ou fase de seqüelas / The contribution of electromyographic analysis of the area for the definition of the stage of development of peripheral facial paralysis: flaccid or sequelae stage

Bernardes, Daniele Fontes Ferreira 12 March 2009 (has links)
OBJETIVO: Avaliar o padrão eletromiográfico em hemiface normal e hemiface afetada nos casos de paralisia facial, em seus dois extremos de evolução; musculatura sem aporte neural e musculatura após a regeneração neural aberrante. MATERIAL E MÉTODO: Foram selecionados indivíduos com paralisia facial periférica unilateral de qualquer etiologia, Idade entre 18 e 69 anos, de ambos os sexos, sem histórico de paralisias faciais prévias ou congênita e sem lesões faciais que interfirissem no contato dos eletrodos. Trinta e quatro indivíduos preencheram os critérios. O grupo controle foi constituído de 20 indivíduos voluntários sem história de paralisia facial, traumas de face ou anomalias craniofaciais. A avaliação da atividade elétrica dos músculos da face foi realizada por meio de registro eletromiográfico, usando equipamento MIOTEC com software MIOTOOL 400, de 04 canais, filtro Passa Baixa, com eletrodos de superfície descartáveis do tipo: Ag-AgCI mini med Kendal. Para a avaliação eletromiográfica foram solicitados os seguintes movimentos: elevação da testa, fechamento de olhos, protrusão labial e retração labial. Além disso, foram registradas as atividades eletromiográficas em outros canais correspondentes aos outros grupos musculares durante a atividade primária a fim de identificar a presença de sincinesias, sendo a atividade dos lábios durante fechamento forçado dos olhos, a atividade dos olhos durante protrusão labial e a atividade dos olhos durante retração labial. A análise estatística foi realizada utilizando-se o software Statistical Package for Social Sciences (SPSS) for Mac versão 16.0 (SPSS Inc, Chicago, IL). Foi considerada como atividade eletromiográfica de cada segmento das hemifaces avaliadas (testa, olho e lábio) durante cada movimento (franzimento a testa, fechamento ocular, protrusão labial e retração labial) o valor médio obtido durante os 8 segundos de registro (em V). O índice da atividade eletromiográfica (IEMG) foi calculado através da divisão da atividade eletromiográfica do lado acometido pela atividade do lado normal para o grupo em estudo e através da divisão da atividade eletromiográfica do lado esquerdo pelo lado direito no grupo controle. RESULTADOS: Houve diferença estatisticamente significante entre os grupos em todos os movimentos analisados. Nas sincinesias no lábio durante o fechamento ocular a totalidade de indivíduos será identificada corretamente (com 100% de verdadeiros positivo e 0% de falsos negativos) utilizando-se o valor de IEMG de 1,62 como ponto de corte. Para a identificação da sincinesia no olho durante a protrusão labial o valor do IEMG no ponto de corte que apresenta ao maior sensibilidade (93,3%) e especificidade (95,9%) é 1,79. CONCLUSÃO: O padrão da atividade eletromiográfica mostrou ser estatisticamente diferente entre os grupos em fase flácida e fase de seqüelas; a relação entre as duas hemifaces é rebaixada nos pacientes em fase flácida e pode tanto mostrar valores normais, elevados ou rebaixados em indivíduos em fase de seqüelas; o IEMG mostrou ser de alta sensibilidade e especificidade na identificação das sincinesias / OBJECTIVE: To evaluate the electromyographic profile in the normal and the affected faces in cases of facial paralysis, in its two extremes of evolution; musculature without neural input and musculature after regeneration neural aberrant. METHODS: Subjects with peripheral facial paralysis unilateral of any etiology, with age ranging from 18 to 69 years, of both sexes, without a history of prior facial paralysis or without congenital facial lesions that would interfere with the contact of electrodes selected. Thirty-four subjects met the criteria. The control group was composed of 20 volunteers without history of facial paralysis, trauma or face craniofacial anomalies. The electromyographic assessment of the facial muscle was performed by means of a MIOTEC equipment with software MIOTOOL 400, 04 channels, low-pass filter, with disposable surface electrodes type: Ag-AgCI mini med Kendal. For the evaluation electromyographic were requested the following movements: lifting the forehead, closure of eyes, protrusion labial and labial retraction. In addition, Eletromyographic activities were recorded in other channels corresponding to the other groups during the primary activity in order to identify the presence of synkinesis, the activity of the lips during strong eye closure, the activity of the eyes during protrusion labial and the activity of eyes during labial retraction. The statistical analysis was performed usingsoftware Statistical Package for Social Sciences (SPSS) version is Mac 16.0 (SPSS Inc, Chicago, IL). The mean value of the RMS during 8 seconds of register (in V) was considered as the electromyographic activity of each segment of hemifaces evaluated (forehead, eye and lip) during each movement. The electromyographic index IEMG was obtained from the division of electromyographic activity (on) of the left side by the right side in the control group. RESULTS: There was a statistically significant difference between the groups in all movements analyzed. The lip synkinesiss during the eye closure in all patients must be correctly identified (with 100% true positive and 0% false negative) using (a) the IEMG value of 1.62 as cutoff point. In order to detect synkinesis in the eye or eye synkinesis during lip protrusion the IEMG at the cutoff point is 1,79 with (a) 93.3% of sensivity and 95,9% of specificity . CONCLUSION: The pattern of electromyographic activity showed to be statistically different between the flaccid and the sequelae groups; the relationship between the two hemifaces is below normal levels in patients at the flaccid stage whereas in patients at the stage of sequelae it can either show normal values, above or below normal levels; the IEMG showed to be of high sensitivity and specificity in the identification of synkinesis
32

Calcium Alleviates Symptoms in Hyperkalemic Periodic Paralysis by Reducing the Abnormal Sodium Influx

DeJong, Danica 02 November 2012 (has links)
Hyperkalemic periodic paralysis, HyperKPP, is an inherited progressive disorder of the muscles caused by mutations in the voltage gated sodium channel (NaV1.4). The objectives of this thesis were to develop a technique for measurement symptoms in vivo using electromyography (EMG) and to determine the mechanism by which Ca2+ alleviates HyperKPP symptoms, since this is unknown. Increasing extracellular [Ca2+] ([Ca2+]e) from 1.3 to 4 mM did not result in any increases in45Ca2+ influx suggesting no increase in intracellular [Ca2+] ([Ca2+]i) acting on an intracellular signaling pathway or on an ion channel such as the Ca2+sensitive K+ channels. HyperKPP muscles have larger TTX-sensitive22Na+ influx than wild type muscles because of the defective NaV1.4 channels. When [Ca2+] was increased from 1.3 to 4 mM, the abnormal 22Na+ influx was completely abolished. Thus, one mechanism by which Ca2+alleviates HyperKPP symptoms is by reducing the abnormal Na+ influx caused by the mutation in the NaV1.4 channel.
33

Gamla tiders nattliga Incubus - En psykisk sjukdom idag? / The Nocturnal Incubus of the Past - A Mental Disorder Today?

Rönnlund, Melody January 2011 (has links)
Sömnparalys innebär att man vaknar upp men inte kan röra sig, och ofta har man skrämmande sinnesupplevelser. Tolkningen och upplevelsen under en sömnparalys kan leda till rädsla att berätta om paralysen, och även om man berättar kan det leda till social stigmatisering och feldiagnostisering.En enkätinsamling gjordes med 100 studenter. Huvudfrågan var om upplevarna av sömnparalys var oroliga för att berätta om det, för att de är rädda att ses som psykiskt sjuka. De som haft sömnparalys berättade för andra, men hellre för någon de känner väl. De och dem som inte upplevt sömnparalys såg det som ett fysiskt problem snarare än ett psykiskt. Risken för stigmatisering och psykisk feldiagnostisering är reducerad, men mer forskning och utbildning i ämnet behövs. / Sleep paralysis means waking up and being unable to move, and are often accompanied with frightening perceptual experiences. The interpretation and experience perceived during sleep paralysis, may lead to fear of telling others about the paralysis, because of the risk for social stigma and misdiagnosis. A survey was conducted with a group of hundred students. The main question was if experiencers are afraid to tell others with the fear of risking been perceived as mentally ill. The experiencers did tell others, but rather to those they knew well. They as well as the non-experiencers viewed it as a physical problem rather than a psychological one. The risk of social stigma and misdiagnosis are reduced, but more research and education in the subject is needed.
34

The Simulation and Analysis of Steering Performance of a Tricycle for the Disabled

Wu, Wen-Jie 19 July 2007 (has links)
This study investigated the rollover behaviors in turning of the tricycle with two front wheels and one rear wheel by neural paralysis. According to the analysis, the researcher fixed radius of gyration and made ride in steady-state turning to obtain the rollover threshold speed of the tricycle. Then we drew different parts of the rollover behaviors with a compuer program, Solidworks. We also decided the steering mechanisms sizes with VB.NET. In Automatic Dynamic Analysis, the researcher identified the rollover problems of the tricycle with the of Mechanical System software (ADAMS). During the researcher, we obtained the highest rollover threshold speed value of the sampling tricycle, and then we adjusted the width, the length of the tricycle. Later on, we adjusted the mass center height of human sizes and the initial rollover threshold speed the tricycle. After getting the best range of rollover threshold speed of the tricycle, the researcher decided appropriate length and height of the bicycle. Finally, we compared rollover behaviors of several different size of new tricycles with the sampling tricycle.
35

Association between reduced limb perfusion and muscle spasticity in persons with spinal cord injury

Parmar, Yesha Jayantilal 15 February 2011 (has links)
Individuals with spinal cord injury (SCI) demonstrate reduced limb blood flow and muscle spasticity. It is plausible that the accumulation of metabolites, resulting from reduced perfusion, could exacerbate spasticity via activation of fusimotor neurons by Group III and IV afferents. PURPOSE: To determine the association between peripheral blood flow and muscle spasticity in persons with SCI. METHODS: A total of 16 individuals with SCI were classified into high (N=6), low (N=5), and no (N=5) spasticity groups according to their spasticity levels indicated by the modified Ashworth scale scores. Blood flow was measured in femoral and brachial arteries using duplex Doppler ultrasound and was normalized to limb lean mass obtained with dual energy X-ray absorptiometry. RESULTS: There were no significant group differences in age (30.5±4.15, 38.48±4.61, 32.6±4.89 years), time post SCI (8.5±4.2, 12.6±4.74, 6.8±1.66 years), American SCI Association motor scores (39.2±7.78, 59±12.34, 53.4±1.08), or sensory scores (96±22.1, 144.4±13.97, 130±13.8). Femoral artery blood flow, adjusted for limb lean mass, was significantly different (p=0.002) across the three leg spasticity groups (high 76.03±6.44, low 95.12±15.49, no 142.53±10.86 ml/min/kg).Total leg muscle spasticity scores were significantly and negatively correlated with femoral artery blood flow (r=-0.60, p=0.014). There was no significant difference in brachial artery blood flow between the three groups, indicating that the reduction in blood flow was confined to injured limbs and not due to systemic cardiovascular disorder. CONCLUSION: Among SCI patients, whole-leg blood flow is progressively lower in individuals with greater spasticity scores. These results suggest that a reduction in lower limb perfusion, among other factors, plays a significant role in the pathogenesis leading to muscle spasticity after SCI. / text
36

The Role of Biomechanics in the Idiopathic Onset of Unilateral Vocal Fold Paralysis

Williams, Megan J. January 2014 (has links)
The vocal folds are important for protection of the airway during swallowing, the regulation of breathing and for voice production. Unilateral vocal fold paralysis (UVP) is caused by damage to the recurrent laryngeal nerve (RLN). Although surgery is most often linked to onset of UVP, the cause remains unknown in 12-42% of those with this disorder [1, 2]. At the level of the aortic arch the RLN branches from the vagus nerve and courses around the arch to ascend back toward the larynx. I hypothesize that an aneurysm of the aorta or alternatively changes in aortic arch compliance could impose increased stress and strain on the RLN where it is adjacent to the aorta resulting in impaired nerve function. The purpose of this research is to develop a computational model based on the biomechanical properties of the left RLN. This model is important for formulating predictions of the typical ranges of stress and strain responses of RLN tissue to forces imposed by surrounding structures (aortic arch). These predictions may be important for future investigations using an animal model to determine the amount of stretch necessary to cause onset of UVP. The first aim of this work was to identify differences in the biomechanical properties in the RLN of piglets between its location within the neck and the portion of the left RLN within the thorax, including the aortic arch region. The distal right RLN segment showed higher maximum tangential modulus (MTM) than the left. With the left nerve the proximal segment (aortic arch region) exhibited higher values of MTM and the stiffness parameter β than the distal segment. This increased stiffness of the proximal region may be in response to the pulsatile forces near the region of the aortic arch. The second aim of this work was to identify difference in the biomechanical properties in adolescent and piglet RLN specimens, between age and between the proximal and distal segments. Additionally the collagen structure of the RLN was imaged with two-photon microscopy to compare the microstructure with the biomechanical response of the RLN tissue. The tangential modulus (TM) and full width half maximum of the collagen fiber distribution (FWHM) was larger in the proximal segments than the distal segments. The strain energy and stiffness parameter α were larger in the piglet than the adolescent pigs while the stiffness parameter β was larger in the adolescent pigs. The purpose of the third aim was to use the material constants from the second aim to create a parametric computational model of the left RLN and the aortic arch. Results indicated that the parameters with the greatest sensitivity to left RLN maximum principal stress and strain are the material properties of the aortic arch. The maximum value of strain found in the RLN region of interest was 16.1%, which may indicate that some combination of aortic arch and RLN properties can elicit damage in the RLN.
37

Genetic analysis of the hereditary spastic paraplegias

Meijer, Inge A. January 2006 (has links)
The Hereditary Spastic Paraplegias (HSP) comprise a group of neurodegenerative diseases characterized by progressive lower limb spasticity. This disease, with a prevalence ranging from 1 to 20 in 100,000 individuals, is currently untreatable. The neuropathological hallmark is axonal degeneration of motor neurons in the corticospinal tract. However, the mechanisms of pathogenesis underlying this neurodegeneration remain poorly understood. Over the last decade, genetic studies of HSP have identified 33 loci including 14 genes. The main objective of this dissertation was to identify and characterize genes in a large North American HSP cohort. Mutation analysis of the two most common genes implicated in HSP, SPG3 and SPG4, led to the detection of nine novel mutations, including an ancestral SPG4 mutation in five French Canadian families. This screen also allowed for the molecular characterization of the p.del436N mutation in SPG3, which suggests a previously unidentified dominant-negative mechanism. Furthermore, a novel deletion in the VPS9 domain of the ALS2 gene was identified in a family with severe infantile onset HSP. In addition, linkage analysis and whole genome scan efforts resulted in the successful mapping of two novel HSP loci, SPG27 and SAX1. SAX1 represents the first locus for autosomal dominant spastic ataxia, a complicated form of HSP, with a common ancestor in Newfoundland. Finally, a positional candidate gene strategy at the SPG8 locus identified three missense mutations in a novel gene encoding strumpellin. Two mutations failed to rescue an axonal phenotype induced by morpholino knock-down of the SPG8 gene in zebrafish. Our efforts to identify and characterize HSP genes determined the underlying genetic cause in 36% of our cohort. These genetic causes include two novel loci and a novel gene. The findings are a major contribution to the characterization of the pathophysiology of HSP and significantly broaden the knowledge in the field of motor neuron disease. Analysis of the 15 known HSP genes suggests a common disease mechanism involving disrupted axonal membrane protein trafficking. Unraveling this mechanism will elucidate the functional maintenance of neurons in the corticospinal tract and will facilitate the development of therapies for HSP and related diseases.
38

Paralysis of Caenorhabditis elegans by Pseudomonas aeruginosa : a genetically tractable model for bacterial pathogenesis /

Darby, Creg Burns. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [64]-73).
39

Irreversible facial paralysis and its treatment

Nicolai, Jean-Philippe Albert. January 1983 (has links)
Thesis (doctoral)--Rijksuniversiteit te Groningen, 1983. / "Stellingen" (1 p.) inserted. Summary in Dutch, French and German. Includes bibliographical references (p. 225-250) and index.
40

Irreversible facial paralysis and its treatment

Nicolai, Jean-Philippe Albert. January 1983 (has links)
Thesis (doctoral)--Rijksuniversiteit te Groningen, 1983. / "Stellingen" (1 p.) inserted. Summary in Dutch, French and German. Includes bibliographical references (p. 225-250) and index.

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