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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.
91

Do topo para a base: aconselhamento genético em famílias a partir da sí­ndrome de tremor/ataxia associada ao X frágil (FXTAS) / From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS)

Ribeiro, Mara Dell\'Ospedale 27 February 2018 (has links)
A Síndrome do X frágil (SXF) é a forma mais comum de deficiência intelectual herdada. É causada por uma mutação no gene FMR1; (Fragile X Mental Retardation 1;), que resulta na deficiência da proteína FMRP (Fragile X Mental Retardation Protein;). O gene FMR1;, localizado no braço longo do cromossomo X, em Xq27.3, possui uma repetição de trinucleotídeos (CGG)n em sua região 5\' não traduzida (região reguladora). Na população geral, o tamanho dessa repetição varia entre 5 a 44 trincas de bases. Uma expansão superior a 200 trinucleotídeos leva à hipermetilação e consequente silenciamento da transcrição do gene. Quando isso ocorre, tem-se uma mutação completa, a causa da SXF. Se a repetição expandida tem de 55 a 200 trincas de bases, chamada de pré-mutação, não ocorre hipermetilação e a proteína FMRP é produzida; portanto, a pré-mutação não está associada à SXF, porém está relacionada a outros quadros clínicos, particularmente à síndrome de tremor/ataxia associada ao X frágil (FXTAS; Fragile-X associated Tremor Ataxia Syndrome;) e à insuficiência ovariana primária associada ao X frágil (FXPOI; Fragile-X associated Primary Ovarian Insufficiency;). O objetivo deste trabalho foi investigar duas famílias cujos casos-índice foram encaminhados para o Centro de Pesquisa sobre o Genoma Humano e Células-Tronco para investigar ataxia espinocerebelar e nos quais a avaliação clínica e a história familial sugeriram a possibilidade de FXTAS; em ambos os pacientes, pré-mutação do gene FMR1; foi detectada. Na Família 1, foi feito o diagnóstico de SXF em um neto da propósita e foi identificada a mutação completa em várias filhas e netas, todas com dificuldade de aprendizado. Na Família 2 não foram identificadas mutações completas e em um dos netos do propósito detectou-se mosaicismo de alelo intermediário e pré-mutação. Assim, diante da variada apresentação fenotípica, a possibilidade de condição associada ao gene FMR1; deve ser considerada frente aos fenótipos de deficiência intelectual, dificuldade de aprendizado, falência ovariana prematura e síndrome de tremor-ataxia. O diagnóstico de FXTAS em famílias em que não há registro de SXF não é frequente, provavelmente diante do desconhecimento dessa possibilidade, mas tem importância fundamental para o aconselhamento genético, particularmente quanto à ocorrência de deficiência intelectual / RIBEIRO, M. D. O. From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS) 2017. 64 f. Dissertação (Mestrado em Aconselhamento Genético e Genômica Humana) - Instituto de Biociências, Universidade de São Paulo, São Paulo, 2017. Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. It is caused by a mutation in the Fragile X Mental Retardation 1 (FMR1;) gene located on the long arm of the X chromosome at Xq27.3 that results in FMRP (Fragile X Mental Retardation Protein) deficiency. The FMR1; gene has a trinucleotide repeat (CGG)n at the 5\' untranslated region (regulatory region); in the general population, this repeat varies in size from 5 to 44 CGG triplets. An expanded repeat of more than 200 trinucleotides leads to hypermethylation and consequent silencing of the gene transcription - the full mutation that causes FXS. The repeat containing 55 to 200 triplets characterizes a premutation; there is no hypermethylation, the gene is transcribed, and the FMRP is produced; then premutations are not associated with FXS, but are related to other clinical conditions: Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI). The objective of this study was to investigate two families whose index cases were referred to the Centro de Pesquisa sobre o Genoma Humano e Células-Tronco to investigate spinocerebellar ataxia, whose clinical evaluation and family history suggested the possibility of FXTAS. Both probands were found to carry FMR1; premutations. In Family 1, the diagnosis of FXS was established in a grandson of the proband, and the full mutation was also identified in several of her daughters and granddaughters, all presenting with learning difficulties. In Family 2, no full mutations were detected; a proband\'s grandson had size mosaicism for FMR1; ; alleles, carrying an intermediate allele and a premutation. Although uncommon, possibly due to lack of knowledge about the syndrome, the diagnosis of FXTAS in families without FXS is important for genetic counseling, particularly regarding the occurrence of intellectual disability
92

Alterações morfológicas e funcionais no sistema estomatognático decorrentes da ataxia espinocerebelar - análise eletromiográfica, eficiência mastigatória, espessura muscular e força de mordida molar máxima / Morphological and functional changes in the stomatognathic system due to spinocerebellar ataxia - electromyographic analysis, masticatory efficiency, muscle thickness and maximum molar bite force

Ferreira, Bruno 26 January 2018 (has links)
A ataxia espinocerebelar é um transtorno neurológico que se manifesta em vias motoras com perda de coordenação dos movimentos, nistagma, distúrbios no controle postural, da marcha, e disfagia. Este estudo teve como objetivo analisar a atividade eletromiográfica, eficiência mastigatória, espessura dos músculos temporal e masseter e força de mordida molar máxima de indivíduos com ataxia e indivíduos que não apresentavam comprometimentos neurológicos. Foram selecionados 28 indivíduos com idade média de 45± 3 anos, de ambos os gêneros, distribuídos em dois grupos pareados: com ataxia (n=14; GA) e sem a doença, controle (n=14; GC). Os músculos temporais e masseteres bilateralmente foram avaliados com as seguintes ferramentas: eletromiografia de superfície nas condições clínicas que exigiram controle postural da mandíbula e mastigação; ultrassonografia, nas condições de repouso e máxima intercuspidação habitual e avaliação da força de mordida molar máxima (direita e esquerda). Os resultados da eletromiografia normalizada, ultrassonografia e força de mordida molar máxima, foram analisados por meio do teste t para amostras independentes considerando valor p<=0,05. Os resultados evidenciaram maior atividade eletromiográfica dos músculos temporais e masseteres em todas as condições posturais da mandíbula para o grupo GA, com diferença significante para o músculo temporal direito (p=0,01) e temporal esquerdo (p=0,05) em protrusão; lateralidade direita (p=0,02) e lateralidade esquerda (p=0,01). Na mastigação, o grupo GA apresentou menor eficiência dos ciclos mastigatórios, com diferença significante para todos os músculos avaliados (p=0,00). Na espessura muscular observou-se maior espessura nos músculos temporais e masseteres para o grupo GA em todas as condições clínicas, exceto para o músculo masseter direito em repouso que apresentou valores semelhantes ao GC, não havendo diferença estatística significante. Quanto à força de mordida molar máxima, o GA apresentou menor média em ambos os lados com diferença estatística significante (p<=0,05). Este estudo sugere que o sistema estomatognático de indivíduos com ataxia apresentam alterações morfológicas e funcionais, principalmente na atividade eletromiográfica, eficiência mastigatória e força de mordida molar máxima. / Spinocerebellar ataxia is a neurological disorder manifested in motor functions with loss of coordination of movements, nystagmus, disorders in postural control, gait and dysphagia. This study aimed to analyze the electromyographic activity, masticatory efficiency, temporal and masseter muscle thickness and maximal molar bite force of individuals with ataxia and individuals who did not present neurological impairments. We selected 28 individuals with the average age of 45± 3 years, of both genders, distributed in two matched groups: with ataxia (n=14; AG) and without the disease, control (n=14; CG). The temporal muscles and masseters were evaluated bilaterally with the following tools: surface electromyography in clinical conditions that required postural control of the mandible and mastication; ultrasonography, in the conditions of rest and maximum habitual intercuspation and evaluation of the maximum molar bite force (right and left). The results of normalized electromyography, ultrasonography and maximum molar bite force were analyzed statistically by t-test for independent samples considering value p<=0.05. The results showed a higher electromyographic activity of the temporal muscles and masseters in all postural conditions of the mandible for the AG group, with a significant difference for the right temporal (p=0.01) and left temporal muscle (p=0.05) on protrusion; right laterality (p=0.02) and left laterality (p=0.01). In chewing, the AG group presented lower efficiency of the masticatory cycles, with a significant difference for all muscles evaluated (p=0.00). Regarding muscle thickness, a greater thickness was observed in the temporal and masseter muscles for the AG group in all clinical conditions, except for the right masseter muscle at rest, which presented values similar to the CG, with no statistically significant difference. Regarding the maximum molar bite force, AG presented lower average on both sides with a significant statistical difference (p<=0.05). This study suggests that the stomatognathic system of individuals with ataxia presents morphological and functional alterations, mainly in the electromyographic activity, masticatory efficiency and maximum molar bite force.
93

Estudo clínico-epidemiológico, laboratorial e de vulnerabilidade dos acidentes escorpiônicos atendidos no Hospital Municipal de Santarém - Pará / Epidemiological, clinical-laboratory and the vulnerability of patient hospitalized for scorpionism at the Municipal Hospital of Santarém (MHS), Pará

Pasesa Pascuala Quispe Torrez 20 June 2016 (has links)
Introdução: Escorpionismo é um problema de saúde no Brasil e em outras regiões do mundo. Em 2015, no Brasil, foram relatados 74.598 acidentes e 119 mortes. Neste estudo, foram descritos aspectos clínicos, epidemiológicos, laboratoriais e de vulnerabilidade nestes acidentes. Métodos: Trata-se de estudo clínico prospectivo e observacional conduzido no Hospital Municipal de Santarém (HMS), de Abril de 2008 a Janeiro de 2014. Os pacientes incluídos no estudo foram admitidos pelo autor e não representam o total de pacientes internados no HMS. Além disso, foi realizado estudo qualitativo com base teórica no conceito de vulnerabilidade que inclui as dimensões individual, social e programática. Resultados: Foram descritos 58 acidentes, presumivelmente, causados por T. obscurus na Amazônia Brasileira. A maioria dos acidentes ocorreu durante o trabalho, a maioria dos pacientes incluídos era do sexo masculino 39 (67,2%). Os principais locais de picada foram as extremidades (pés e mãos) com uma frequência de 51 (90%). Os pacientes relataram sensação de \"choques elétricos\" que podem durar horas. A grande maioria dos pacientes apresenta quadro clínico compatível com disfunção cerebelar aguda, que pode ter início minutos e durar até dois dias após a ocorrência do acidente. Apresentaram ataxia cerebelar, disdiadococinesia, dismetria, disartria, dislalia, naúseas e vômitos. Além disso, alguns pacientes, aprentaram mioclonias e fasciculações que também podem ser atribuídas à disfunção cerebelar aguda ou talvez à ação direta sobre o músculo esquelético. Seis pacientes apresentaram rabdomiólise e dois injúria renal aguda. O quadro clínico observado na maioria dos pacientes consiste, principalmente, em disfunção cerebelar aguda e manifestações neuromusculares anormais, que não foram descritos em qualquer outra região do mundo. Também foram realizadas 28 entrevistas quanti-qualitativas com pacientes vítimas de acidente escorpiônico, as quais foram submetidas à técnica de análise de discurso. Pacientes eram, em sua maioria, homens que moravam na área rural e que trabalhavam como agricultores e viviam em condições sócio demográficas desfavoráveis. Discussão: As manifestações apresentadas por esses pacientes são compatíveis com disfunção cerebelar aguda que pode ser explicada, provavelmente, porque algumas toxinas de T. obscurus (da região de Santarém), não só tem a capacidade de atravessar rapidamente, em poucos minutos, a barreira hemato-encefálica, mas também devem apresentar elevada afinidade por canais iônicos presentes nas membranas de células do cerebelo. As mioclonias e fasciculações podem ser atribuídas à disfunção muscular ou cerebelar. A vulnerabilidade individual e social foi evidenciada em vários aspectos: pouco conhecimento em relação ao comportamento de escorpiões e também às medidas preventivas, baixa escolaridade (incluindo analfabetismo), baixa qualificação profissional, trabalho informal, condições precárias de vida (falta de água encanada, energia elétrica, esgoto). Em relação à dimensão programática foi constatada dificuldade de acesso aos serviços de saúde e a falta de antiveneno no centro de referência. Portanto, o estudo destaca as particularidades do escorpionismo em Santarém e os aspectos mais importantes da vulnerabilidade destes pacientes / Introduction: Scorpionism is a health problem in Brazil and in another regions of the world. In 2015, in Brazil 74,598 accidents and 119 deaths were reported. In this study, were described clinical, epidemiologic, laboratory and vulnerability aspects of these unique scorpion accidents. Methods: A prospective and observational study was conducted in the MHS, from April, 2008 to January, 2014. Patients included in the study were admitted by the authors and do not represent the total number of hospitalized patients in the MHS. In addition, a qualitative study was conducted with the theoretical basis of the vulnerability concept, that includes individual, social and programmatic dimension. Results: We described 58 accidents presumably caused by T. obscurus in Brazilian Amazonia. Most patients were stung during work activities and the majority was male 39 (67.2%). The main sites of stung were the extremities (feet and hands), with a frequency of 51 (90%).Patients reported a sensation of \"electric shocks\" which could last hours. The vast majority of patients presented a clinical picture compatible with acute cerebellar dysfunction, that started in minutes and could last up to two days after the accident. They presented cerebellar ataxia, dysdiadocokinesia, dysmetry, dysarthria, dyslalia, nausea and vomiting. Also, some patients presented myoclonus and fasciculation which can also be attributed to cerebellar dysfunction or perhaps the result of direct action on skeletal muscle. Six patients had developed rhabdomyolysis and two acute kidney injury. The clinical picture observed in most of our patients consisted mainly from an acute cerebellar dysfunction and abnormal neuromuscular manifestations which is not described in any other region of the world. Twenty-eight quantitative and qualitative interviews with scorpion sting victims. Each patient was submitted to discourse analysis technique. The majority patients were men who live in rural areas, small farmers with unfavorable socio-demographic conditions. Discussion: The manifestations presented by these patients are compatible with acute cerebellar dysfunction which could be explained probably because some toxins from T. obscurus from Santarém region, have not only the capacity to cross quickly, within minutes, the blood-brain and also must have high affinity for ionic channels present in some cerebellar cell membranes. Myoclonus and fasciculation can be attributed to cerebellar or muscle dysfunction. The individual and social vulnerability was demonstrated in several ways: little knowledge about the scorpion behavior and about the preventive measures, low education level (including illiteracy), low-skilled, informal work, precarious living conditions (lack of running water, electricity, basic sanitation). Regarding the programmatic dimension it was found difficult access to health services and lack of antivenom serum in the reference center. Therefore, the study highlights the particularities of scorpionism in Santarem and the most important aspects of vulnerability of these patients
94

Étude clinique et génétique d’une nouvelle forme d’ataxie spinocérébelleuse pure associée à l’Érythrokératodermie

Turcotte Gauthier, Maude 04 1900 (has links)
Nous présentons ici la description clinique et génétique d’un syndrome neurocutané unique. Le laboratoire du Dr Cossette a entrepris la caractérisation clinique et génétique d'une famille canadienne-française qui a été identifiée par les Drs Giroux et Barbeau en 1972 et qui comprend plus de 100 personnes sur six générations. Les membres atteints de cette famille présentent des lésions typiques d'érythrokératodermie (EK) (OMIM 133190, EKV1 et EKV2), associées à une ataxie spinocérébelleuse pure. Dans cette famille, l'ataxie est caractérisée par des troubles de la coordination et de la démarche causés par une dégénérescence du cervelet et de la moelle épinière. Cette ataxie est transmise selon un mode autosomique dominant. Une étude antérieure de cette variante d'EK avec ataxie avait suggéré une liaison sur le chromosome 1p34-p35, soit la même région que les formes EKV de type 1 et 2, causées respectivement par des mutations dans les gènes connexin-31 (GJB3; OMIM 603324) et connexin-30.3 (GJB4; OMIM 605425). Cependant, aucune mutation n'a été retrouvée dans ces gènes pour la famille canadienne-française. Nous avons récemment recontacté la famille et effectué des examens détaillés, incluant une imagerie par résonance magnétique (IRM) et un électromyogramme (EMG). Les manifestations neurologiques des individus atteints sont compatibles avec une nouvelle forme d’ataxie cérébelleuse pure à transmission autosomique dominante (ADCA de type III dans la classification de Harding) que nous avons appelée SCA34. Une cartographie complète du génome nous a permis de localiser le gène SCA34 sur le chromosome 6p12.3-q16.2. Également, en collaboration avec les Drs Alexis Brice (Hôpital Pitié-La Salpêtrière, Paris) et Alfredo Brusco (Hôpital San Giovanni Battista di Torino, Italie), nous avons confirmé que trois autres familles européennes avec SCA inexpliquée étaient également liées au locus SCA34. Notre laboratoire a récemment entrepris la recherche des mutations responsables de SCA34. Les résultats de ce criblage de gènes candidats sont présentés dans le chapitre 3 de cette thèse. / We present here the clinical and genetic description of a unique neuro-cutaneous syndrome. Dr. Cossette’s laboratory began the clinical and genetic characterization of a French-Canadian family who was identified by Drs. Giroux and Barbeau in 1972 and includes more than 100 people over six generations. The affected members of this family have typical lesions of erythrokeratodermia (EK) (OMIM 133190, and EKV1 EKV2), associated with pure spinocerebellar ataxia. In this family, the clinical phenotype is characterized by gait ataxia caused by degeneration of the cerebellum and spinal cord and the pattern of inheritance is compatible with an autosomal dominant trait. In a previous study of this variant of ataxia with EK, putative linkage was found on chromosome 1p34-p35, the same chromosomal region of EKV1 and EKV2 that are respectively caused by mutations in the connexin-31 gene (GJB3, OMIM 603324) and connexin -30.3 (GJB4, OMIM 605425). However, no mutations have been found in these latter genes for the French-Canadian family. We recently contacted the family and carried out detailed examinations, including a magnetic resonance imaging (MRI) and electromyography (EMG). Neurological manifestations of affected individuals are consistent with a new form of pure autosomal dominant cerebellar ataxia, (ADCA type III in the classification of Harding) that we named SCA34. A whole genome scan allowed us to map the gene on chromosome 6p12.3-q16.2. Interestingly, in collaboration with Dr. Alexis Brice (Hôpital Pitié-La Salpêtrière, Paris), and Alfredo Brusco (San Giovanni Battista Hospital, Turin, Italy), we found that three additional European families with unexplained SCA were also linked to the SCA34 locus. Our laboratory has recently begun the search for mutations causing SCA34. The results of this screening of candidate genes are presented in Chapter 3 of this thesis.
95

Concentrações de vitaminas C e E em pacientes com ataxia telangiectasia: relação com biomarcadores associados a aterosclerose e ao estresse oxidativo. / Concentrations of vitamins C and E in patients with ataxia telangiectasia: relationship to biomarkers associated whit atherosclerosis and oxidative stress

Andrade, Itana Gomes Alves [UNIFESP] January 2013 (has links) (PDF)
Made available in DSpace on 2015-12-06T23:46:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2013 / Introdução: A ataxia telangiectasia (AT) e uma doenca neurodegenerativa, que cursa com imunodefiCiência em graus variaveis, disfuncao mitocondrial e exacerbacao do estresse oxidativo. Objetivo: avaliar o estado nutricional, perfil lipidico, peroxidacao lipidica e as concentracoes plasmaticas de vitaminas C e E e relaciona-las com biomarcadores associados ao risco de aterosclerose de pacientes com AT e controles. Metodos: Estudo transversal controlado envolvendo 13 pacientes e 22 controles saudaveis, pareados por genero e idade. Foram avaliados: estado nutricional, consumo alimentar, perfil lipidico e suas relacoes, concentracoes plasmaticas de vitaminas C e E, malondialdeido (MDA) e proteina C reativa ultrassensivel (PCRus). Resultados: A media de idade do grupo AT foi 14,6 anos; 4/13 (30,8%) eram desnutridos e 3/13 (23,1%) apresentavam baixa estatura para idade. Os pacientes apresentaram maior comprometimento de massa magra comparativamente aos controles. As concentracoes de triglicerides, colesterol total e de LDL-c foram significantemente mais elevadas nos pacientes e as de HDL-c, mais baixas. As relacoes associadas ao risco de aterosclerose (CT/HDL-c, LDL-c/HDL-c e Log TG/HDL-c) e o colesterol nao HDL (NHDL-c) foram significantemente superiores no grupo de pacientes em comparacao aos controles. Nao houve diferenca para as concentracoes de malondialdeido, proteina C reativa e de vitaminas C e E entre os dois grupos. As relacoes vitamina E/lipideos totais e vitamina E/triglicerides mostraram valores mais baixos no grupo de pacientes; correlacao significante e inversa entre estas relacoes e NHDL-c, CT/HDL-c, LDL-c/HDL-c e Log TG/HDL-c foi observada no grupo de pacientes. A alanina aminotransferase (ALT) correlacionou-se de forma direta e significante com NHDL-c, CT/HDL-c e LDL-c/HDL-c, no grupo de pacientes. A inGestão dietetica de energia, macronutrientes e de vitaminas C e E nao diferiu entre os grupos. Conclusao: O elevado risco aterosclerotico de pacientes com AT aliado ao comprometimento da defesa antioxidante e do estado nutricional pode complicar a evolucao da doenca e enfatiza a importancia da atencao multiprofissional com monitoramento de biomarcadores e orientacao nutricional apropriada / Introduction: Ataxia telangiectasia (AT) is a neurodegenerative disease that leads to immunodeficiency in varying degrees, mitochondrial dysfunction and oxidative stress. Objective: To evaluate the nutritional status, lipid profile, lipid peroxidation, and plasma concentrations of vitamins C and E and relate them with biomarkers associated with risk of atherosclerosis in patients with AT and controls. Methods: Cross sectional and controlled study involving 13 patients and 22 controls healthy, matched by gender and age. We evaluated: nutritional status, food intake, lipid profile and their relationships, plasma concentrations of vitamins C and E, malondialdehyde (MDA) and high-sensitivity C-reactive protein (hs CRP). Results: The mean age of the AT group was 14.6 years, 4/13 (30.8%) were malnourished and 3/13 (23.1%) had stunting. The patients showed greater impairment of lean body mass compared to controls. The concentrations of triglycerides, total cholesterol and LDL-c were significantly higher in patients and of HDL-c,lower. The ratios associated with the risk of atherosclerosis (TC/ HDL-c, and LDL-c/HDL-c Log TG / HDL-c) and non-HDL cholesterol (NHDL-c) were significantly higher in patients compared to controls. There was no difference in concentrations of malondialdehyde, C-reactive protein and vitamins C and E between the two groups. The ratios vitamin E / total lipids and vitamin E / triglycerides showed lower values in the group of patients; significant inverse between these ratiosand NHDL-c, TC/ HDL-c, and LDL-c/HDL-c Log TG / HDL -c was observed in the AT group. Alanine aminotransferase (ALT) correlated directly and significantly with NHDL-C, TC / HDL-c and LDL-c/HDL-c, in patients. Dietary intake of energy, macronutrients and vitamins C and E did not differ between groups. Conclusion: The high atherosclerotic risk of patients with AT coupled with impaired antioxidant defense and nutritional status may complicate the clinical course of the disease and emphasizes the importance of multidisciplinary care with monitoring of appropriate biomarkers and nutrition al guidance. / BV UNIFESP: Teses e dissertações
96

Alterações morfológicas e funcionais no sistema estomatognático decorrentes da ataxia espinocerebelar - análise eletromiográfica, eficiência mastigatória, espessura muscular e força de mordida molar máxima / Morphological and functional changes in the stomatognathic system due to spinocerebellar ataxia - electromyographic analysis, masticatory efficiency, muscle thickness and maximum molar bite force

Bruno Ferreira 26 January 2018 (has links)
A ataxia espinocerebelar é um transtorno neurológico que se manifesta em vias motoras com perda de coordenação dos movimentos, nistagma, distúrbios no controle postural, da marcha, e disfagia. Este estudo teve como objetivo analisar a atividade eletromiográfica, eficiência mastigatória, espessura dos músculos temporal e masseter e força de mordida molar máxima de indivíduos com ataxia e indivíduos que não apresentavam comprometimentos neurológicos. Foram selecionados 28 indivíduos com idade média de 45± 3 anos, de ambos os gêneros, distribuídos em dois grupos pareados: com ataxia (n=14; GA) e sem a doença, controle (n=14; GC). Os músculos temporais e masseteres bilateralmente foram avaliados com as seguintes ferramentas: eletromiografia de superfície nas condições clínicas que exigiram controle postural da mandíbula e mastigação; ultrassonografia, nas condições de repouso e máxima intercuspidação habitual e avaliação da força de mordida molar máxima (direita e esquerda). Os resultados da eletromiografia normalizada, ultrassonografia e força de mordida molar máxima, foram analisados por meio do teste t para amostras independentes considerando valor p<=0,05. Os resultados evidenciaram maior atividade eletromiográfica dos músculos temporais e masseteres em todas as condições posturais da mandíbula para o grupo GA, com diferença significante para o músculo temporal direito (p=0,01) e temporal esquerdo (p=0,05) em protrusão; lateralidade direita (p=0,02) e lateralidade esquerda (p=0,01). Na mastigação, o grupo GA apresentou menor eficiência dos ciclos mastigatórios, com diferença significante para todos os músculos avaliados (p=0,00). Na espessura muscular observou-se maior espessura nos músculos temporais e masseteres para o grupo GA em todas as condições clínicas, exceto para o músculo masseter direito em repouso que apresentou valores semelhantes ao GC, não havendo diferença estatística significante. Quanto à força de mordida molar máxima, o GA apresentou menor média em ambos os lados com diferença estatística significante (p<=0,05). Este estudo sugere que o sistema estomatognático de indivíduos com ataxia apresentam alterações morfológicas e funcionais, principalmente na atividade eletromiográfica, eficiência mastigatória e força de mordida molar máxima. / Spinocerebellar ataxia is a neurological disorder manifested in motor functions with loss of coordination of movements, nystagmus, disorders in postural control, gait and dysphagia. This study aimed to analyze the electromyographic activity, masticatory efficiency, temporal and masseter muscle thickness and maximal molar bite force of individuals with ataxia and individuals who did not present neurological impairments. We selected 28 individuals with the average age of 45± 3 years, of both genders, distributed in two matched groups: with ataxia (n=14; AG) and without the disease, control (n=14; CG). The temporal muscles and masseters were evaluated bilaterally with the following tools: surface electromyography in clinical conditions that required postural control of the mandible and mastication; ultrasonography, in the conditions of rest and maximum habitual intercuspation and evaluation of the maximum molar bite force (right and left). The results of normalized electromyography, ultrasonography and maximum molar bite force were analyzed statistically by t-test for independent samples considering value p<=0.05. The results showed a higher electromyographic activity of the temporal muscles and masseters in all postural conditions of the mandible for the AG group, with a significant difference for the right temporal (p=0.01) and left temporal muscle (p=0.05) on protrusion; right laterality (p=0.02) and left laterality (p=0.01). In chewing, the AG group presented lower efficiency of the masticatory cycles, with a significant difference for all muscles evaluated (p=0.00). Regarding muscle thickness, a greater thickness was observed in the temporal and masseter muscles for the AG group in all clinical conditions, except for the right masseter muscle at rest, which presented values similar to the CG, with no statistically significant difference. Regarding the maximum molar bite force, AG presented lower average on both sides with a significant statistical difference (p<=0.05). This study suggests that the stomatognathic system of individuals with ataxia presents morphological and functional alterations, mainly in the electromyographic activity, masticatory efficiency and maximum molar bite force.
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Do topo para a base: aconselhamento genético em famílias a partir da sí­ndrome de tremor/ataxia associada ao X frágil (FXTAS) / From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS)

Mara Dell\'Ospedale Ribeiro 27 February 2018 (has links)
A Síndrome do X frágil (SXF) é a forma mais comum de deficiência intelectual herdada. É causada por uma mutação no gene FMR1; (Fragile X Mental Retardation 1;), que resulta na deficiência da proteína FMRP (Fragile X Mental Retardation Protein;). O gene FMR1;, localizado no braço longo do cromossomo X, em Xq27.3, possui uma repetição de trinucleotídeos (CGG)n em sua região 5\' não traduzida (região reguladora). Na população geral, o tamanho dessa repetição varia entre 5 a 44 trincas de bases. Uma expansão superior a 200 trinucleotídeos leva à hipermetilação e consequente silenciamento da transcrição do gene. Quando isso ocorre, tem-se uma mutação completa, a causa da SXF. Se a repetição expandida tem de 55 a 200 trincas de bases, chamada de pré-mutação, não ocorre hipermetilação e a proteína FMRP é produzida; portanto, a pré-mutação não está associada à SXF, porém está relacionada a outros quadros clínicos, particularmente à síndrome de tremor/ataxia associada ao X frágil (FXTAS; Fragile-X associated Tremor Ataxia Syndrome;) e à insuficiência ovariana primária associada ao X frágil (FXPOI; Fragile-X associated Primary Ovarian Insufficiency;). O objetivo deste trabalho foi investigar duas famílias cujos casos-índice foram encaminhados para o Centro de Pesquisa sobre o Genoma Humano e Células-Tronco para investigar ataxia espinocerebelar e nos quais a avaliação clínica e a história familial sugeriram a possibilidade de FXTAS; em ambos os pacientes, pré-mutação do gene FMR1; foi detectada. Na Família 1, foi feito o diagnóstico de SXF em um neto da propósita e foi identificada a mutação completa em várias filhas e netas, todas com dificuldade de aprendizado. Na Família 2 não foram identificadas mutações completas e em um dos netos do propósito detectou-se mosaicismo de alelo intermediário e pré-mutação. Assim, diante da variada apresentação fenotípica, a possibilidade de condição associada ao gene FMR1; deve ser considerada frente aos fenótipos de deficiência intelectual, dificuldade de aprendizado, falência ovariana prematura e síndrome de tremor-ataxia. O diagnóstico de FXTAS em famílias em que não há registro de SXF não é frequente, provavelmente diante do desconhecimento dessa possibilidade, mas tem importância fundamental para o aconselhamento genético, particularmente quanto à ocorrência de deficiência intelectual / RIBEIRO, M. D. O. From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS) 2017. 64 f. Dissertação (Mestrado em Aconselhamento Genético e Genômica Humana) - Instituto de Biociências, Universidade de São Paulo, São Paulo, 2017. Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. It is caused by a mutation in the Fragile X Mental Retardation 1 (FMR1;) gene located on the long arm of the X chromosome at Xq27.3 that results in FMRP (Fragile X Mental Retardation Protein) deficiency. The FMR1; gene has a trinucleotide repeat (CGG)n at the 5\' untranslated region (regulatory region); in the general population, this repeat varies in size from 5 to 44 CGG triplets. An expanded repeat of more than 200 trinucleotides leads to hypermethylation and consequent silencing of the gene transcription - the full mutation that causes FXS. The repeat containing 55 to 200 triplets characterizes a premutation; there is no hypermethylation, the gene is transcribed, and the FMRP is produced; then premutations are not associated with FXS, but are related to other clinical conditions: Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI). The objective of this study was to investigate two families whose index cases were referred to the Centro de Pesquisa sobre o Genoma Humano e Células-Tronco to investigate spinocerebellar ataxia, whose clinical evaluation and family history suggested the possibility of FXTAS. Both probands were found to carry FMR1; premutations. In Family 1, the diagnosis of FXS was established in a grandson of the proband, and the full mutation was also identified in several of her daughters and granddaughters, all presenting with learning difficulties. In Family 2, no full mutations were detected; a proband\'s grandson had size mosaicism for FMR1; ; alleles, carrying an intermediate allele and a premutation. Although uncommon, possibly due to lack of knowledge about the syndrome, the diagnosis of FXTAS in families without FXS is important for genetic counseling, particularly regarding the occurrence of intellectual disability
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Avaliação das escalas ICARS (International Cooperative Ataxia Rating Scale) e SARA (Scale for the Assessment of Rating Ataxia) e exames de ressonância magnética na doença de Machado-Joseph / Magnetic resonance imaging and ICARS and SARA assessment in Machado-Joseph disease

Guimarães, Rachel Paes, 1984- 20 August 2018 (has links)
Orientadores: Fernando Cendes, Iscia T. Lopes-Cendes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T13:47:21Z (GMT). No. of bitstreams: 1 Guimaraes_RachelPaes_D.pdf: 1465604 bytes, checksum: 8d25df109e02b8f6f7c12483cebf584d (MD5) Previous issue date: 2012 / Resumo: A doença de Machado Joseph (MJD) ou ataxia espinocerebelar tipo 3 (SCA3) é uma doença autossômica dominante e é o tipo de ataxia mais comum no Brasil. Os principais sintomas são ataxia, alterações de movimentação ocular, distonia, espasticidade e disfunção piramidal e fasciculações, além de disfagia e disartria. Estes usualmente tem início na idade adulta, entre os 30-40 anos. Apesar de ser frequente, existem poucos biomarcadores para a avaliação da progressão da doença. O objetivo deste estudo foi avaliar a SB cerebelar e cerebral de indivíduos com MJD/SCA3 através da técnica de Imagem por tensor de difusão (DTI) e Morfometria baseada em Vóxel (VBM), além de correlacionar os dados de duas escalas específicas para ataxia, a International Cooperative Ataxia Rating Scale (ICARS) e a Scale for the Assessment and Rating of Ataxia (SARA) com as imagens de ressonância magnética. Para tanto foram selecionados 38 pacientes com diagnóstico de MJD/SCA3, confirmado por meio de teste molecular, além de 38 indivíduos controles. Todos passaram por exame de ressonância magnética, e os acometidos pela MJD/SCA3 foram avaliados através de exame neurológico e as escalas ICARS e SARA. As análises de DTI feitas através do Tract-Based Spatial Statistics (TBSS) demonstraram redução da anisotropia fracional em tronco cerebral, lobo cerebelar anterior, mesencéfalo, lobo cerebelar posterior à direita, nódulo, culmen, núcleo denteado e fastigial. Foram encontradas também áreas com aumento de difusividade radial e axial em tronco encefálico, ponte, mesencéfalo, lobo cerebelar anterior, núcleo denteado, fastigium e tálamo. Aumento de difusividade radial também foi encontrado em lobos frontal e temporal. Não foram encontradas áreas com alteração de difusividade média. Uma correlação positiva entre os valores de anisotropia fracional extraídos da ponte com o tempo de duração da doença foi encontrada. Os resultados da VBM demonstraram atrofia de substância branca em tonsila, lobo cerebelar posterior, medula, tronco cerebral direito, ponte, culmen, declive, vermis, giro lingual, giro fusiforme, núcleo denteado, úvula e pirâmide. Foi encontrada uma correlação negativa entre densidade de SB e os escores das escalas ICARS e SARA e tempo de duração da doença. Atrofia de substância cinzenta em lobo cerebelar posterior, tonsila, medula, tronco encefálico, lóbulo semi-lunar inferior, declive, tuber e pirâmide. Correlações entre a densidade de SC e dados clínicos demonstraram correlação negativa com os escores das escalas ICARS e SARA e o tamanho da expansão CAG. O presente estudo apresenta informações relevantes sobre alterações microestruturais em SB e macroestruturais em SB e SC na MJD/SCA3. Acreditamos que esses achados contribuam para um melhor entendimento sobre o processo neuropatológico desta doença / Abstract: Machado Joseph Disease or spinocerebellar ataxia type 3 (MJD/SCA3) is an autosomal dominant ataxia and it is the most common in Brasil and in the world. The main symptoms are ataxia, extraocular movement disorders, dystonia, disfagia, spasticity, pyramidal dysfunction and fasciculation. The symptoms usually appear between 30-40 years. The objective of the present study was to assess cerebellar and cerebral white matter in MJD/SCA3 patients through Diffusion Tensor Imaging (DTI) and Voxel Based Morphometry (VBM) and to correlate clinical data obtained by two scales that are specific for ataxia, the International Cooperative Ataxia Rating Scale (ICARS) and Scale for the Assessment and Rating of Ataxia (SARA) with magnetic resonance imaging findings. For that purpose we recruited 38 patients with a confirmed molecular diagnosis of MJD/SCA3 and 38 healthy individuals as a control group. All subjects were underwent MRI scan, and patients were assessed by neurological examination, ICARS and SARA. DTI analysis with Tract-Based Statistical Analysis (TBSS) revealed fractional anisotropy (FA) reduction in the brainstem, the anterior and posterior cerebellar lobes, midbrain, culmen, dentate and fastigial. Areas with increased axial (AD) and radial diffusivity (RD) were found in brainstem, pons, midbrain, cerebellar anterior lobe and thalamus. Increased RD was also evidenced in frontal and temporal lobes. TBSS analysis revealed no alterations in mean diffusivity.A positive correlation between FA values extracted from pons and disease duration was found. VBM results demonstrated white matter atrophy at tonsil, posterior cerebellar lobe, medulla, brainstem, pons, culmen, declive, vermis, lingual gyrus, fusiform gyrus, dentate, uvula and pyramis. We found a negative correlation between white matter density and SARA, ICARS scores and disease duration. Grey matter atrophy was demonstrated at posterior cerebellar lobe, tonsil, medulla, brainstem, inferior semi-lunar lobule, declive, tuber and pyramis. A negative correlation between grey matter density, SARA and ICARS scores and CAG repeat size was found / Doutorado / Neurociencias / Mestre em Fisiopatologia Médica
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PKC gamma regulates connexin 57

Snider, Adam K. January 1900 (has links)
Master of Science / Department of Biochemistry / Dolores J. Takemoto / Spinocerebellar ataxia type 14 (SCA14) is a rare, autosomal dominant neurodegenerative disease caused by mutations in the gene encoding for protein kinase Cγ (PKCγ). These mutations affect the translocation and activation of the protein and are particularly damaging to the Purkinje cells of the cerebellum. This translocation and activation leads to the down regulation of gap junction activity by direct phosphorylation on the C-terminal tail of connexin proteins. This process is necessary in terminating the propagation of apoptotic signaling and is disrupted by SCA14-type mutations. Gap junctions allow the passive diffusion of small molecules from one adjoining cell to another. Gap junctions function as electrical synapses in neuronal tissue and are formed from connexin proteins. The connexin family of proteins contains approximately 20 members, each of which is expressed in a tissue dependent manner. One of the dominant connexin proteins expressed in Purkinje cells is connexin 57 (Cx57). Here, I have tested if Cx57 is regulated by PKCγ. This thesis shows that activation of PKC and PKCγ caused internalization of Cx57 gap junction plaques in HT-22 cell culture. PKC and PKCγ activation led to the phosphorylation of Cx57 primarily on serine residues. Furthermore, the expression of SCA14-type PKCγ led to increased sensitivity to oxidative stress, resulting decreased cell viability.
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An investigation of the importance of the ATM protein in the endothelium and its role in the signalling pathways of NO production

Collop, Natalie Chantel 04 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Ataxia telangiectasia (AT) is a well-characterized neurodegenerative disease resulting from a genetic defect in the Atm gene causing an absence or very low expression of the ATM protein. As AT patients are prone to the development of insulin resistance and atherosclerosis, the aim or the current study was to investigate the importance of the ATM protein in the endothelium and its role in the signalling pathways of nitric oxide (NO) production. To accomplish this, the first objective was to establish an in-house endothelial cell isolation technique harvested from normal and insulin resistant animals. Unfortunately, these cultures, although staining positive with an endothelial cell specific stain, were not pure enough and did not express endothelial NO synthase (eNOS), the central enzyme in NO production. The remainder of the study utilized commercial aortic endothelial cells (AECs) and found that there was a significant increase in NO production when the ATM protein was inhibited by the specific inhibitor, Ku-60019. The beneficial impact of increased NO production includes maintaining vascular homeostasis, promoting angiogenesis, initiating DNA repair by activating p53 and inhibiting smooth muscle cell proliferation. On the other hand, reactive oxygen species (ROS) and reactive nitrogen species (RNS) also generated by high levels of NO, can exert both protective and harmful effects. Examples of these include cell death due to high concentrations of ROS. However, Ku-60019 did not result in increased cell death of AECs. We demonstrated for the first time, a relationship between endothelial ATM protein kinase and the generation of NO. The signalling pathways involved in NO production and glucose utilization form a network of interrelationships. Central to both pathways is the activity of two protein kinases, PKB/Akt and AMPK. Both these kinases are known to phosphorylate the eNOS enzyme to produce NO on the one hand and AS160 to induce GLUT 4 translocation and glucose uptake on the other hand. Activation of the ATM protein is postulated to be a prerequisite for PKB/Akt activation and it may also result in activation of AMPK. However, using insulin to stimulate ATM, we could not show that inhibition of ATM in endothelial cells affected expression or insulin-stimulated activation of PKB/Akt while the PI3-K inhibitor wortmannin, inhibited the latter. In addition, inhibition of ATM negatively regulated the phospho/total ratio of AMPK. We therefore postulate that the NO production elicited by inhibition of ATM, may not be as result of eNOS activity. A second important observation was that inhibition of ATM significantly enhanced phosphorylation of the p85 regulatory subunit of PI3-K. This would imply that ATM normally has an inhibitory effect on p85 phosphorylation and therefore PI3-K activation. We base this assumption on previous publications showing that Ku-60019 does not inhibit PI3K. This again indicates that ATM has a hitherto unexplored regulatory role in endothelial function. / AFRIKAANSE OPSOMMING: Ataxia telangiectasia (AT) is a goed-gekarakteriseerde neurodegeneratiewe siekte a.g.v. ‘n genetiese afwyking in the Atm geen wat lei tot ‘n afwesige of lae uitdrukking van die ATM proteïen. Aangesien AT pasiënte geneig is om insulienweerstandigheid en aterosklerose te ontwikkel, was die doel van hierdie studie om die belang van die ATM proteïen in die endoteel, en sy rol in die seintransduksiepaaie betrokke by stikstofoksied (NO) produksie, te ondersoek. Om dit te bereik, was die eerste mikpunt om ‘n eie endoteelsel isolasie-tegniek (ge-oes van normale en insulienweerstandige diere) te vestig. Ongelukkig was hierdie selkulture nie suiwer genoeg nie.Ten spyte daarvan dat hulle positief getoets het met ‘n endoteelsel-spesifieke kleurstof kon geen uitdrukking van eNOS, die sentrale ensiem verantwoordelik vir NO produksie, waargeneem word nie. Die res van die studie het van kommersiële aorta endoteelselle (AES) gebruik gemaak, en daar is gevind dat die inhibisie van die ATM proteïen met die spesifieke inhibitor, Ku-60019, tot ‘n beduidende toename in NO produksie gelei het. Die voordelige impak van verhoogde NO produksie sluit die handhawing van vaskulêre homeostase, bevordering van angiogenese, inisiëring van DNA herstel deur p53 aktivering en inhibisie van gladdespiersel proliferasie in. Reaktiewe suurstofspesies (ROS) en reaktiewe stikstofspesies (RNS) wat ook a.g.v.verhoogde NO gegenereer word, kan egter beide beskermende sowel as skadelike effekte uitoefen. Voorbeelde sluit seldood a.g.v. hoë ROS konsentrasies in. Ku-60019 het egter nie tot ‘n toename in seldood van die AES gelei nie. Hierdie studie het vir die eerste keer aangetoon dat daar ‘n verwantskap tussen die endoteel ATM proteïen kinase en die produksie van NO bestaan. Die seintransduksie paaie betrokke by NO produksie en glukose verbruik vorm ‘n interafhanklike netwerk. Die aktiwiteit van twee proteïen kinases, PKB/Akt en AMPK, is sentrale rolspelers in beide paaie. Albei hierdie kinases is daarvoor bekend dat hulle die eNOS ensiem fosforileer om NO te produseer, maar terselfdertyd ook lei tot AS160 fosforilering, wat tot GLUT 4 translokering en glukose opname lei. Dis is voorgestel dat aktivering van die ATM proteïen ‘n voorvereiste vir PKB/Akt aktivering mag wees en verder kan dit ook tot aktivering van AMPK lei. Ons kon nie aantoon dat inhibisie van ATM in endoteelselle die uitdrukking of insulien-geïnduseerde aktivering van PKB/Akt onderdruk nie, terwyl die PI3-K inhibitor, wortmannin, wel laasgenoemde geïnhibeer het. Verder het die inhibisie van ATM die fosfo/totale AMPK verhouding negatief gereguleer. Ons postuleer dus dat die NO produksie waargeneem tydens ATM inhibisie, moontlik nie die gevolg van eNOS aktiwiteit was nie. ‘n Tweede belangrike waarneming was dat die inhibisie van ATM die fosforilering van die p85 regulatoriese subeenheid van PI3-K beduidend laat toeneem het. Dit impliseer dat ATM normaalweg ‘n inhibitoriese effek op p85 fosforilering, en dus PI3-K aktivering, het. Hierdie aanname word gemaak n.a.v. vorige publikasies wat getoon het dat Ku-60019 nie PI3-K inhibeer nie. Dit dui weer eens daarop dat ATM ‘n tot nog toe onbekende regulatoriese rol in endoteelfunksie het.

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