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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.
21

Avaliação da qualidade de vida em pacientes adultos com neurofibromatose tipo 1

Protas, Júlia Schneider January 2016 (has links)
Base teórica: A qualidade de vida é uma variável amplamente estudada nas ciências da saúde e tem se tornado, cada vez mais, um indicativo importante na avaliação dos estados e desfechos de saúde. As doenças crônicas se caracterizam por curso prolongado, por vezes acompanhando o portador por toda sua vida, o que pode influenciar a percepção que o indivíduo tem de si mesmo e de sua vida. A Neurofibromatose tipo 1 (NF1) é uma doença crônica, genética, que atinge cerca de 1:3500 nascimentos. Além de ser uma doença que acarreta uma maior predisposição ao desenvolvimento de tumores, a NF1 possui sintomas físicos de fácil identificação. Objetivo: O presente estudo visa estudar a qualidade de vida e algumas variáveis emocionais de pessoas com neurofibromatose tipo 1. Método: Trata-se de um estudo transversal. Foram avaliadas as variáveis de qualidade de vida genérica (WHOQOL-bref e SF-36), qualidade de vida específica para pessoas com problemas de pele (DLQI-bra), sintomas depressivos (BDI), sintomas de ansiedade(BAI), percepção de suporte familiar (IPSF) e estratégias de enfrentamento (Inventário de Estratégias de Coping de Folkman e Lazarus). Os participantes deste estudo também foram avaliados quanto à gravidade (Escala de Riccardi) e visibilidade dos sintomas da doença (Ablon). Resultados: Foram coletados dados de 71 pacientes adultos com NF1. Do total 60,0% da amostra foram pessoas do sexo feminino, a média de idade foi de ± 40,36 anos. Dos 52 pacientes avaliados pela escala de Riccardi, 11,3% apresentou gravidade leve, 40,4% gravidade moderada, 42% sintomas graves de gravidade e 6,5% sintomas muito graves da doença. Com relação a visibilidade dos sintomas medidos pela escala de Ablon, 36,5% apresentam visibilidade leve de sintomas, 30,8% visibilidade moderada e 32.7% visibilidade severa dos sintomas. Conclusão: Os resultados da avaliação de qualidade de vida de pessoas com NF1, ao serem comparados com os dados normativos para amostra, não apresentou diferença estatisticamente significativa. A análise dos sintomas depressivos indicou que grande parte dos entrevistados apresentam sintomas leves de depressão e os dados da escala BAI referente aos sintomas de ansiedade constatou que a média dos entrevistados apresentam sintomas graves de ansiedade, podendo sugerir que a ansiedade seja uma característica importante dessa população. As estratégias de enfrentamento mais utilizadas por esta população foram a reavaliação e o suporte social. Com relação aos resultados da percepção de suporte familiar, podemos perceber que os dados da amostra não apresentaram diferença significativa ao serem comparados com os dados normativos da escala. / Theoretical basis: Quality of life is an important studied variable in health sciences and has become an important indicator in assessing states and health outcome. Chronic diseases are characterized by a prolonged course, sometimes accompanying the carrier all his life, which can influence the perception that the individual has of himself and of his life. The neurofibromatosis type 1 (NF1) is a chronic and genetics condition that affects about 1: 3500 births. Besides being a disease that leads to a greater predisposition to develop tumors, NF1 has physical symptoms of easy identification. Objective: This project aims to study the quality of life and emotional variables of people with neurofibromatosis type 1. Method: This is an observational study. The overall quality of life variables were evaluated (WHOQOL-bref and SF-36), specific quality of life for people with skin problems (DLQI-bra), depressive symptoms (BDI), anxiety symptoms (BAI), perception of family supports (IPSF) and coping strategies (coping strategies Inventory of Folkman and Lazarus). The participants were also evaluated for the severity (Riccardi Scale) and visibility of disease symptoms (Ablon). Results: Were collected data from 71 adults patients with NF1. From all sample 60% were female. The mean age was ± 40.36 years . Of the 52 patients evaluated for Riccardi scale , 11.3 % had mild severity , 40.4 % moderate severity , 42% Severity of symptoms and 6.5 % symptoms very severe. The data of the visibility of the symptoms were measure by Ablon scale , 36.5 % have mild symptoms visibility , 30.8 % moderate and 32.7 % severe visibility of symptoms. Conclusion: The results of the quality of life of people with NF1, when compared with the normative data for sample, indicate no statistically significant difference. The analysis of depressive symptoms indicated that the majority of respondents have mild symptoms of depression and the BAI scale data related to symptoms of anxiety found that the average of respondents have severe anxiety symptoms and may suggest that anxiety can be an important feature of this population. Coping strategies most used by this population were the re-evaluation and social support. Regarding the results of the perception of family support, we can see that the sample data showed no significant difference when compared with the normative data range.
22

Etude des gènes LIMK2 et RNF135, impliqués dans les mécanismes moléculaires de la neurofibromatose de type 1, dans l'autisme et la déficience mentale / Study of LIMK2 and RNF135, involved in neurofibromatosis type 1, in autism and mental deficiency

Tastet, Julie 26 June 2012 (has links)
L'autisme et la déficience mentale (DM) sont des pathologies neurodéveloppementales fréquentes qui partagent des facteurs génétiques communs. Afin de mieux comprendre leur étiologie, nous avons étudié les mécanismes moléculaires de la neurofibromatose de type 1 (NF1), qui est souvent associée à l'autisme et à la DM. La neurofibromine, dont le gène est muté dans la NF1 interagit avec LIMK2. Cette protéine fait partie de la voie des Rho-GTPases dont des mutations de plusieurs membres ont été trouvés mutés dans des cas d'autisme et de DM. Chez le rat, nous avons montré que l’expression de Limk2d, une isoforme sans domaine kinase, augmente la croissance des neurites des cellules neuronales NSC-34. Chez l'homme, LIMK2-1 est la seule isoforme qui comporte un domaine inhibiteur de la phosphatase 1 (PP1i). Nous avons montré que l’expression de cette protéine diminue la longueur des neurites des cellules NSC-34 in vitro. Nous avons observé l'association de la variation située dans le domaine PP1i à la DM (p.S668P, rs151191437) (p=0,04, test de Fisher, OR = 3,29). Elle abolit l’effet inhibiteur de croissance des neurites de l'isoforme LIMK2-1 diminue l'interaction de LIMK2-1 avec la neurofibromine. La fréquence de l'autisme est plus élevée chez les patients atteints ayant des délétions de 14 gènes du locus NF1. Nous avons observé une association entre la variation R115K (rs111902263) du gène RNF135 de ce locus et l'autisme (p=0,00014, test de Fisher) ainsi qu’une anomalie du nombre de copies située dans l'intron 2 de ce gène chez un d’entre eux. Ce travail souligne la spécificité de deux isoformes de LIMK2 sur la croissance des neurites. Il renforce l’intérêt d’étudier l’implication du gène RNF135 dans l’autisme. Des études fonctionnelles seront entreprises afin de confirmer le rôle de LIMK2 et de RNF135 dans l'étiologie de l'autisme et de la DM. / Autism and mental deficiency (MD) are two neurodevelopemental diseases which share genetic factors in common. To better understand their etiologies, we studied the molecular mechanisms of neurofibromatosis type 1, a pathology frequently associated with autism and MD. Neurofibromatosis type 1 is due to deletions or mutations of the NF1 gene which encodes neurofibromin. This protein interacts with several proteins such as LIMK2. This protein belongs to the Rho-GTPases pathway in wich mutations of numerous members have been associated with autism and MD. In our study, we showed that LIMK2 isoforms do not only have important structural differencies but have also functional specificities. Limk2d, which lacks the kinase domain, promotes neurite outgrowth of NSC-34 cells. On the contrary, LIMK2-1, which is primate specific and has a C-terminal PP1i domain, inhibits neurite outgrowth. Analysis of the LIMK2-1 coding sequence, revealed the association between MD and a variation located in the PP1i domain, S668P (rs151191437) (p=0.04, Fisher test, OR = 3.29). This variation abrogated the LIMK2-1 effect on neurite outgrowth and inhibited LIMK2-1 interaction with neurofibromin. Deletions occuring in neurofibromatosis type 1 which include the NF1 gene and 13 others are associated with a higher frequency of autism. Mutations of one of them, RNF135, have been identified in patients with MD and overgrowth syndrome. Two of these patients also presented autistic features. By analysing RNF135 gene in autistic patients, we showed the association of the variation R115K (rs111902263) with autism. We also identified a duplication of a region located in RNF135 gene intron 2 in one patient presenting autism and MD. Our results highlight the importance and specificity of LIMK2 isoforms on neurite outgrowth and strengthen the importance to analyze both the sequence and copy-number of RNF135 gene. Further functional experiments will be undertaken to confirm the implication of LIMK2 and RNF135 in autism and MD etiology.
23

Les LIM kinases dans la neurofibromatose de type 1 : caractérisation cellulaire et moléculaire de LIMK2-1, une isoforme associée à la déficience intellectuelle / LIM kinases in neurofibromatosis type 1 : cellular and molecular characterization of LIMK2-1, an isoform associated with intellectual disability

Cuberos, Hélène 21 June 2016 (has links)
LIMK1 et LIMK2 sont des sérines/thréonine kinases capables de phosphoryler et d’inactiver la cofiline, un facteur de dépolymérisation de l’actine. Elles sont régulées négativement par la neurofibromine, responsable de la neurofibromatose de type 1, et pourraient être impliquées à la fois dans les aspects tumoraux et cognitifs de cette maladie par leur rôle dans la dynamique de l’actine. Nous avons étudié l’isoforme LIMK2‐1 de LIMK2, spécifique des hominidés et précédemment associée à la déficience intellectuelle. Cette isoforme possède un domaine kinase tronqué et un domaine inhibiteur de la phosphatase 1 (PP1i) en C‐terminal. Nos résultats montrent, d’une part, que LIMK2‐1 existe sous forme de protéine et qu’elle est exprimée dans le système nerveux central chez l’homme, en particulier au cours du neurodéveloppement. D’autre part, il apparaît que cette isoforme favorise la polymérisation de l’actine. Cette action semble indépendant de l’activité kinase puisque LIMK2‐1 ne phosphoryle pas la cofiline. Nous avons également montré que le domaine PP1i interagissait spécifiquement avec la phosphatase 1 et des résultats complémentaires suggèrent un rôle de ce domaine dans l’inhibition de la dépolymérisation de l’actine. Ces données mettent en évidence un mécanisme moléculaire nouveau pour une protéine de la famille des LIMK et soulignent l’intérêt d’étudier ces protéines afin de mieux comprendre leur implication dans les troubles cognitifs et dans la neurofibromatose de type 1. / LIMK1 and LIMK2 are serine/threonine kinases that phosphorylate and subsequently inactivate cofilin, an actin-depolymerizing factor. Neurofibromin, the protein responsible for neurofibromatosis type 1, negatively regulates these proteins that may be involved in tumoral and cognitive aspects of the disease through their role in actin dynamics. We studied LIMK2-1, a hominidae-specific isoform previously involved in intellectual disability. This isoform possesses a truncated kinase domain and a protein phosphatase 1 inhibitory (PP1i) domain at its C-terminal extremity. Our results showed that LIMK2-1 exists at a protein level and that it is expressed in human central nervous system, especially during neurodevelopment. Moreover, LIMK2-1 promotes actin polymerization independently from a kinase activity, since this isoform does not phosphorylate cofiline. We also highlighted an interaction between the PP1i domain and protein phosphatase 1 and complementary results suggest a role of this domain in the inhibition of actin depolymerization. These data highlight a new molecular mechanism for a LIMK protein and emphasize the interest of studying these proteins to understand their involvement in cognitive disorders and in neurofibromatosis type 1.
24

Avaliação da qualidade de vida em pacientes adultos com neurofibromatose tipo 1

Protas, Júlia Schneider January 2016 (has links)
Base teórica: A qualidade de vida é uma variável amplamente estudada nas ciências da saúde e tem se tornado, cada vez mais, um indicativo importante na avaliação dos estados e desfechos de saúde. As doenças crônicas se caracterizam por curso prolongado, por vezes acompanhando o portador por toda sua vida, o que pode influenciar a percepção que o indivíduo tem de si mesmo e de sua vida. A Neurofibromatose tipo 1 (NF1) é uma doença crônica, genética, que atinge cerca de 1:3500 nascimentos. Além de ser uma doença que acarreta uma maior predisposição ao desenvolvimento de tumores, a NF1 possui sintomas físicos de fácil identificação. Objetivo: O presente estudo visa estudar a qualidade de vida e algumas variáveis emocionais de pessoas com neurofibromatose tipo 1. Método: Trata-se de um estudo transversal. Foram avaliadas as variáveis de qualidade de vida genérica (WHOQOL-bref e SF-36), qualidade de vida específica para pessoas com problemas de pele (DLQI-bra), sintomas depressivos (BDI), sintomas de ansiedade(BAI), percepção de suporte familiar (IPSF) e estratégias de enfrentamento (Inventário de Estratégias de Coping de Folkman e Lazarus). Os participantes deste estudo também foram avaliados quanto à gravidade (Escala de Riccardi) e visibilidade dos sintomas da doença (Ablon). Resultados: Foram coletados dados de 71 pacientes adultos com NF1. Do total 60,0% da amostra foram pessoas do sexo feminino, a média de idade foi de ± 40,36 anos. Dos 52 pacientes avaliados pela escala de Riccardi, 11,3% apresentou gravidade leve, 40,4% gravidade moderada, 42% sintomas graves de gravidade e 6,5% sintomas muito graves da doença. Com relação a visibilidade dos sintomas medidos pela escala de Ablon, 36,5% apresentam visibilidade leve de sintomas, 30,8% visibilidade moderada e 32.7% visibilidade severa dos sintomas. Conclusão: Os resultados da avaliação de qualidade de vida de pessoas com NF1, ao serem comparados com os dados normativos para amostra, não apresentou diferença estatisticamente significativa. A análise dos sintomas depressivos indicou que grande parte dos entrevistados apresentam sintomas leves de depressão e os dados da escala BAI referente aos sintomas de ansiedade constatou que a média dos entrevistados apresentam sintomas graves de ansiedade, podendo sugerir que a ansiedade seja uma característica importante dessa população. As estratégias de enfrentamento mais utilizadas por esta população foram a reavaliação e o suporte social. Com relação aos resultados da percepção de suporte familiar, podemos perceber que os dados da amostra não apresentaram diferença significativa ao serem comparados com os dados normativos da escala. / Theoretical basis: Quality of life is an important studied variable in health sciences and has become an important indicator in assessing states and health outcome. Chronic diseases are characterized by a prolonged course, sometimes accompanying the carrier all his life, which can influence the perception that the individual has of himself and of his life. The neurofibromatosis type 1 (NF1) is a chronic and genetics condition that affects about 1: 3500 births. Besides being a disease that leads to a greater predisposition to develop tumors, NF1 has physical symptoms of easy identification. Objective: This project aims to study the quality of life and emotional variables of people with neurofibromatosis type 1. Method: This is an observational study. The overall quality of life variables were evaluated (WHOQOL-bref and SF-36), specific quality of life for people with skin problems (DLQI-bra), depressive symptoms (BDI), anxiety symptoms (BAI), perception of family supports (IPSF) and coping strategies (coping strategies Inventory of Folkman and Lazarus). The participants were also evaluated for the severity (Riccardi Scale) and visibility of disease symptoms (Ablon). Results: Were collected data from 71 adults patients with NF1. From all sample 60% were female. The mean age was ± 40.36 years . Of the 52 patients evaluated for Riccardi scale , 11.3 % had mild severity , 40.4 % moderate severity , 42% Severity of symptoms and 6.5 % symptoms very severe. The data of the visibility of the symptoms were measure by Ablon scale , 36.5 % have mild symptoms visibility , 30.8 % moderate and 32.7 % severe visibility of symptoms. Conclusion: The results of the quality of life of people with NF1, when compared with the normative data for sample, indicate no statistically significant difference. The analysis of depressive symptoms indicated that the majority of respondents have mild symptoms of depression and the BAI scale data related to symptoms of anxiety found that the average of respondents have severe anxiety symptoms and may suggest that anxiety can be an important feature of this population. Coping strategies most used by this population were the re-evaluation and social support. Regarding the results of the perception of family support, we can see that the sample data showed no significant difference when compared with the normative data range.
25

Avaliação da qualidade de vida em pacientes adultos com neurofibromatose tipo 1

Protas, Júlia Schneider January 2016 (has links)
Base teórica: A qualidade de vida é uma variável amplamente estudada nas ciências da saúde e tem se tornado, cada vez mais, um indicativo importante na avaliação dos estados e desfechos de saúde. As doenças crônicas se caracterizam por curso prolongado, por vezes acompanhando o portador por toda sua vida, o que pode influenciar a percepção que o indivíduo tem de si mesmo e de sua vida. A Neurofibromatose tipo 1 (NF1) é uma doença crônica, genética, que atinge cerca de 1:3500 nascimentos. Além de ser uma doença que acarreta uma maior predisposição ao desenvolvimento de tumores, a NF1 possui sintomas físicos de fácil identificação. Objetivo: O presente estudo visa estudar a qualidade de vida e algumas variáveis emocionais de pessoas com neurofibromatose tipo 1. Método: Trata-se de um estudo transversal. Foram avaliadas as variáveis de qualidade de vida genérica (WHOQOL-bref e SF-36), qualidade de vida específica para pessoas com problemas de pele (DLQI-bra), sintomas depressivos (BDI), sintomas de ansiedade(BAI), percepção de suporte familiar (IPSF) e estratégias de enfrentamento (Inventário de Estratégias de Coping de Folkman e Lazarus). Os participantes deste estudo também foram avaliados quanto à gravidade (Escala de Riccardi) e visibilidade dos sintomas da doença (Ablon). Resultados: Foram coletados dados de 71 pacientes adultos com NF1. Do total 60,0% da amostra foram pessoas do sexo feminino, a média de idade foi de ± 40,36 anos. Dos 52 pacientes avaliados pela escala de Riccardi, 11,3% apresentou gravidade leve, 40,4% gravidade moderada, 42% sintomas graves de gravidade e 6,5% sintomas muito graves da doença. Com relação a visibilidade dos sintomas medidos pela escala de Ablon, 36,5% apresentam visibilidade leve de sintomas, 30,8% visibilidade moderada e 32.7% visibilidade severa dos sintomas. Conclusão: Os resultados da avaliação de qualidade de vida de pessoas com NF1, ao serem comparados com os dados normativos para amostra, não apresentou diferença estatisticamente significativa. A análise dos sintomas depressivos indicou que grande parte dos entrevistados apresentam sintomas leves de depressão e os dados da escala BAI referente aos sintomas de ansiedade constatou que a média dos entrevistados apresentam sintomas graves de ansiedade, podendo sugerir que a ansiedade seja uma característica importante dessa população. As estratégias de enfrentamento mais utilizadas por esta população foram a reavaliação e o suporte social. Com relação aos resultados da percepção de suporte familiar, podemos perceber que os dados da amostra não apresentaram diferença significativa ao serem comparados com os dados normativos da escala. / Theoretical basis: Quality of life is an important studied variable in health sciences and has become an important indicator in assessing states and health outcome. Chronic diseases are characterized by a prolonged course, sometimes accompanying the carrier all his life, which can influence the perception that the individual has of himself and of his life. The neurofibromatosis type 1 (NF1) is a chronic and genetics condition that affects about 1: 3500 births. Besides being a disease that leads to a greater predisposition to develop tumors, NF1 has physical symptoms of easy identification. Objective: This project aims to study the quality of life and emotional variables of people with neurofibromatosis type 1. Method: This is an observational study. The overall quality of life variables were evaluated (WHOQOL-bref and SF-36), specific quality of life for people with skin problems (DLQI-bra), depressive symptoms (BDI), anxiety symptoms (BAI), perception of family supports (IPSF) and coping strategies (coping strategies Inventory of Folkman and Lazarus). The participants were also evaluated for the severity (Riccardi Scale) and visibility of disease symptoms (Ablon). Results: Were collected data from 71 adults patients with NF1. From all sample 60% were female. The mean age was ± 40.36 years . Of the 52 patients evaluated for Riccardi scale , 11.3 % had mild severity , 40.4 % moderate severity , 42% Severity of symptoms and 6.5 % symptoms very severe. The data of the visibility of the symptoms were measure by Ablon scale , 36.5 % have mild symptoms visibility , 30.8 % moderate and 32.7 % severe visibility of symptoms. Conclusion: The results of the quality of life of people with NF1, when compared with the normative data for sample, indicate no statistically significant difference. The analysis of depressive symptoms indicated that the majority of respondents have mild symptoms of depression and the BAI scale data related to symptoms of anxiety found that the average of respondents have severe anxiety symptoms and may suggest that anxiety can be an important feature of this population. Coping strategies most used by this population were the re-evaluation and social support. Regarding the results of the perception of family support, we can see that the sample data showed no significant difference when compared with the normative data range.
26

Difficultés motrices, cognitives et comportementales chez les enfants et adolescents atteints de neurofibromatose de type 1 (maladie de von Recklinghausen) / Motor, cognitive, and behavioral difficulties in children and adolescents with neurofibromatosis type 1 (von Recklinghausen disease)

Coutinho, Virginie 16 October 2015 (has links)
Les données de la littérature concernant les difficultés cognitives et comportementales dans la Neurofibromatose de type 1 (NF1) sont nombreuses avec des résultats parfois contradictoires. Après une revue de la littérature, ce travail de recherche : (i) décrit les difficultés comportementales, cognitives et motrices chez 78 patients atteints de NF1, âgés de 5 à 18 ans, au moyen de questionnaires aux parents (qualité de vie, impact de la maladie, difficultés des parents eux-mêmes, Conners, BRIEF, CBCL), et d'une évaluation de l'efficience intellectuelle et neuropsychologique détaillée ; (ii) analyse les relations entre les aspects cliniques, comportementaux, neuropsychologiques et l'imagerie (présence ou non d'« Objets Brillants Non Identifiés » caractéristiques de la NF1). Les difficultés d'apprentissage, malgré une qualité de vie plutôt bonne et un faible impact de la maladie, les troubles attentionnels et l'anxiété de l'enfant constituaient les principales sources d'inquiétude des parents. Les questionnaires étaient corrélés entre eux, mais ils étaient peu liés aux tests neuropsychologiques. La présence de difficultés cognitives spécifiques, en particulier visuo-spatiales et en motricité fine, a été confirmée. Aucune relation n'a pu être établie entre la neuropsychologie et l'imagerie. Les difficultés neuropsychologiques étaient plus sévères dans les formes familiales que sporadiques. / Cognitive and behavioral difficulties are common in children with Neurofibromatosis type 1 (NF1), however findings concerning the specific neuropsychological and behavioral profile as well as the association of these difficulties with clinical manifestations and brain imagery abnormalities are often contradictory. After a literature review, the present study: (i) describes behavioral, cognitive, and motor difficulties in 78 patients with NF1, aged 5 to 18 years, using parental questionnaires (quality of life, impact of illness, parental difficulties, Conners, BRIEF, CBCL), and tests of intellectual efficiency and specific neuropsychological functions; (ii) examines the relationships between clinical, behavioral, neuropsychological and imaging findings (presence or absence of "Unidentified Bright Objects" UBOs, characteristic feature of NF1). Learning disabilities, despite relatively good report of quality of life, attention disorders and child anxiety were the main parental concerns. All parental questionnaires were strongly inter-correlated, and associated with an overall positive or negative parental attitude during the interview with the psychologist. Parental concerns were only weakly related to neuropsychological tests. The presence of specific cognitive difficulties, particularly in visuospatial and fine motor skills, was confirmed. Imaging data were not associated with neuropsychological scores. Cognitive difficulties were more important in familial than sporadic forms.
27

Études électroencéphalographiques et relations avec le fonctionnement neuropsychologique chez les enfants ayant la neurofibromatose de type 1

Lalancette, Eve 11 1900 (has links)
La neurofibromatose de type 1 (NF1) est une condition génétique entraînant des répercussions dans différents systèmes, y compris le système nerveux. Les enfants atteints de la NF1 sont à risque de rencontrer différents défis sur le plan cognitif et comportemental. Un chevauchement avec les symptômes associés à d’autres troubles neurodéveloppementaux, notamment le trouble déficitaire de l’attention avec ou sans hyperactivité (TDAH) et le trouble du spectre de l’autisme (TSA), est d’ailleurs présent dans cette condition génétique. Les études réalisées avec des modèles animaux de NF1 ont permis d’identifier des déséquilibres dans la neurotransmission qui pourraient sous-tendre les déficits cognitifs. Comment ces déséquilibres se traduisent sur le plan de l’activité cérébrale chez l’humain ayant la NF1 demeure peu compris à ce jour. L’objectif général de cette thèse est donc d’étudier, à l’aide de l’électroencéphalographie (EEG), les réponses neuronales lors du traitement sensoriel chez les enfants ayant la NF1 ainsi que les associations avec le fonctionnement cognitif et comportemental. Dans le premier article, nous avons étudié l’intégrité de la réponse de synchronisation neuronale lors de stimulations visuelles rythmiques à différentes fréquences. Considérant l’importance des déficits visuo-perceptifs ainsi que les indices de perturbations de la transmission GABAergique au niveau du cortex occipital dans la NF1, nous avons émis l’hypothèse d’une réduction de la synchronisation neuronale dans le groupe NF1 par rapport au groupe d’enfants neurotypiques. Une puissance réduite de la synchronisation neuronale a effectivement été trouvée dans la NF1, particulièrement en réponse à la plus haute fréquence de stimulation. Cette réponse neuronale affaiblie a été corrélée à une plus grande sévérité des symptômes comportementaux du TDAH. Cela soulève la possibilité d’une modulation de la réponse sensorielle par les réseaux attentionnels et soulève également des questions en lien avec l’impact du diagnostic de TDAH en comorbidité avec la NF1. L’impact de la médication psychostimulante, testé avec un sous-groupe de l’échantillon NF1, s’est d’ailleurs révélé par une amélioration de la réponse de synchronisation neuronale à la plus faible fréquence de stimulation. La réponse de synchronisation neuronale apparait donc comme un marqueur à investiguer davantage pour comprendre les mécanismes qui sous-tendent les déficits cognitifs dans la NF1 et pour évaluer l’impact de traitements. Dans le deuxième article, nous avons étudié les oscillations cérébrales dans la réponse de suppression neuronale et de détection du changement, toujours en comparant un groupe d’enfants ayant la NF1 à un groupe d’enfants neurotypiques. Une modulation atypique des oscillations cérébrales était attendue dans la NF1 en réponse à la répétition et au changement dans la séquence de stimuli audio-visuels. Les résultats ont démontré une réponse de suppression neuronale préservée dans le groupe NF1, mais une puissance accrue des oscillation thêta dans la condition de détection du changement. Les symptômes comportementaux du TDAH ont été associés à une réduction de la puissance des oscillations dans la réponse de détection du changement et ne contribueraient donc pas à la réponse accrue identifiée dans le groupe NF1. En somme, les résultats de la thèse ont permis d’identifier des particularités dans les réponses électrophysiologiques du traitement sensoriel chez les enfants ayant la NF1 et de mettre de l’avant des mesures dont le potentiel translationnel pourrait faciliter le transfert des connaissances accumulées dans les modèles animaux de NF1. Les résultats soulignent la complexité d’établir les bases neuronales des déficits cognitifs dans la NF1 compte tenu de l’hétérogénéité du profil cognitif. Cela dit, les associations établies entre les réponses neuronales et les symptômes comportementaux du TDAH suggèrent la possibilité de considérer le profil électrophysiologique pour guider le développement de traitements et interventions visant à améliorer le fonctionnement cognitif chez les enfants ayant la NF1. / Neurofibromatosis type 1 (NF1) is a genetic condition that has implications across different systems, including the nervous system. Children with NF1 are at risk of facing various cognitive and behavioral challenges. An overlap with symptoms associated with other neurodevelopmental disorders, including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), is also present in this genetic condition. Studies conducted using animal models of NF1 have identified imbalances in neurotransmission that may underlie cognitive deficits. However, how these imbalances translate into human brain activity in individuals with NF1 remains poorly understood to date. The overall objective of this thesis is to investigate, using electroencephalography (EEG), neural responses during sensory processing in children with NF1 and their associations with cognitive and behavioral functioning. In the first article, we studied the integrity of the neural synchronization response during rhythmic visual stimulation at different frequencies. Given the significance of visuo-perceptual deficits as well as indications of disrupted GABAergic transmission in the occipital cortex of individuals with NF1, we hypothesized a reduction in neural synchronization in the NF1 group compared to neurotypical children. Reduced power of neural synchronization was indeed found in NF1, particularly in response to the highest stimulation frequency. This weakened neural response was correlated with greater severity of ADHD behavioral symptoms. These results suggest a possible modulation of this sensory response by attentional networks and raise questions regarding the impact of comorbid ADHD diagnosis on neural activity in NF1. The intake of psychostimulant medication, in a subgroup of the NF1 sample, resulted in an increased neural synchronization at the lowest stimulation frequency. Neural synchronization should be further investigated as a potential biomarker in NF1 and could help understand the underlying mechanisms of cognitive deficits and assess the impact of treatments. In the second article, we studied brain oscillations in the repetition suppression and change detection response, again comparing a group of children with NF1 to a group of neurotypical children. Atypical modulation of brain oscillations was expected in NF1 in response to repetition and change in the audio-visual stimuli sequence. Results showed preserved repetition suppression response in the NF1 group, but increased power of theta oscillations in the change detection condition. Behavioral symptoms of ADHD were associated with reduced oscillatory power in the change detection response, which suggest that the ADHD comorbidity did not contribute to the increased response identified in the NF1 group. In summary, results of this thesis have demonstrated distinct electrophysiological responses during sensory processing in children with NF1 and have highlighted measures with translational potential that could facilitate the transfer of knowledge gained from animal models of NF1. The results emphasize the complexity of establishing the neural basis of cognitive deficits in NF1, given the heterogeneity of the cognitive profile. However, the associations established between neural responses and ADHD behavioral symptoms suggest the possibility of considering the electrophysiological profile to guide the development of treatments and interventions aimed at improving cognitive functioning in children with NF1.
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Untersuchung des Einflusses mitochondrialer Polymorphismen auf die phänotypische Ausprägung der Neurofibromatose Typ 1 bei monozygoten Zwillingen

Detjen, Anne Katrin 21 November 2005 (has links)
Einleitung: Die Entdeckung somatischer homoplasmischer Mutationen der mitochondrialen DNA (mtDNA) in Tumoren gab Anlass zu der Frage, ob Mutationen der mtDNA einen Einfluss auf Entstehung und Wachstum von Tumoren haben könnten. Die Neurofibromatose Typ 1 (NF1, von Recklinghausen) ist eine der häufigsten erblichen Tumorerkrankungen mit einer Penetranz von 100%, aber hoher phänotypischer Variabilität. Selbst eineiige Zwillinge können sich erheblich in ihrem Phänotyp unterscheiden. Durch die ungleiche Verteilung der Mitochondriengenome auf die Embryonen könnten heteroplasmische mtDNA-Polymorphismen den Phänotyp der Neurofibromatose Typ 1 unterschiedlich beeinflussen. Ziel dieser Arbeit war es herauszufinden, ob es interindividuelle Unterschiede in der mtDNA-Sequenz monozygoter Zwillinge gibt, die an Neurofibromatose Typ 1 erkrankt sind, sich jedoch im Phänotyp unterscheiden. Des Weiteren habe ich nach intraindividuellen Unterschieden der mtDNA-Sequenz zwischen Blut und Tumorgewebe gesucht. Die Frage war, ob es somatische mtDNA-Mutationen gibt, die einen Einfluss auf das Entstehen der Tumore haben könnten. Innerhalb der mtDNA gibt es hypervariable Regionen (HVR), von denen der oft in heteroplamischer Form vorkommende D310-Trakt im D-loop als Marker für klonales Wachstum in Tumoren empfohlen wurde. Ich habe versucht, durch Analyse des D-loops der mtDNA aus Neurofibromen klonales Wachstum nachzuweisen. Methoden: Ich habe die mitochondriale DNA vier monozygoter Zwillingspaare untersucht. Die DNA wurde sowohl aus Blutleukozyten als auch aus Neurofibromen extrahiert. Ich habe zunächst mit mtDNA-spezifischen Primern eine Long-range PCR durchgeführt. Mit dem Long-range PCR-Produkt als Matrize habe ich in 17 verschachtelten PCR Reaktionen Fragmente generiert und diese sequenziert. Den relativen Anteil heteroplasmischer Längenvarianten des D310-Traktes ermittelte ich mittels Genotypisierung. Ergebnisse: Beim Vergleich der mtDNA-Sequenzen mit der mtDNA Standardsequenz (Genbank, NC_001807) habe ich insgesamt 88 Abweichungen gefunden. Die meisten waren in der Datenbank Mitomap verzeichnet. Es fanden sich keine interindividuellen Unterschiede innerhalb der einzelnen Paare. Beim Vergleich der mtDNA-Sequenzen aus Blut- mit denen aus Tumorzellen eines Zwillingspaares fand ich keinen intraindividuellen Unterschied. Der D310-Trakt innerhalb der HVR2 kam bei allen Zwillingspaaren in heteroplasmischer Form vor. Bei den Zwillingen A1 und A2 sowie deren Mutter MA konnte ich annähernd die gleiche Verteilung der Löngenvarianten in Blutzellen sowie in Neurofibromen von A1 und A2 zeigen. Schlussfolgerungen: Ich konnte keinen Hinweis dafür finden, dass Veränderungen in der mtDNA die phänotypische Ausprägung der NF1 beeinflussen. In Neurofibromen konnte ich durch Untersuchung des D310-Traktes keinen Hinweis auf klonales Wachstum finden. / Introduction: The discovery of homoplasmic somatic mutations of the mitochondrial DNA (mtDNA) led to the question whether mutations of mtDNA could influence tumor development and growth. Neurofibromatosis Type 1 (NF1) is one of the most common inherited disorders. Penetrance of the disease is 100%, but phenotypic variability is high, even amongst identical twins. I wanted to test the hypothesis, whether the unequal distribution of heteroplasmic mtDNA variants between the embryos might influence NF1 phenotype. The aim of this study was to look for interindividual differences of the mtDNA sequence between identical twins. In order to detect somatic mutation that could possibly influence tumor development I searched for intraindividual differences between blood- and tumor-mtDNA. The hypervariable D310-tract within the D-loop is heteroplasmic in most individuals, but shows a tendency towards homoplasmy in tumors. Therefore, it has been proposed as marker for clonal tumor growth. I tried to identify clonal growth in cutaneous neurofibromas by examination of the D310-tract. Methods: I examined the mtDNA from four pairs of identical twins. MtDNA was extracted from blood-leucocytes as well as from neurofibromas. With DNA-specific primers I first performed a long-range PCR. The product was then reamplified as 17 nested PCR fragments and sequenced afterwards. The relative amount of heteroplasmic D310-tract length variants was analyzed by genotyping. Results: Taken together, I identified 88 deviations from the mtDNA standard sequence (Genbank NC_001807). Most of these variants were already known as polymorphisms in the database MITOMAP. I could neither find any interindividual differences between the individuals of a twin pair nor intraindividual differences between blood- and tumor-mtDNA. The D310-tract was heteroplasmic in all twin pairs. Twins A1 and A2 as well as their mother showed almost the same distribution of length variants in blood and tumor. Conclusion: I could not show that mtDNA polymorphisms play a role in phenotypic variability of NF1. Examination of the D310 tract in cutaneous neurofibromas did not show signs of clonal growth.
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Inteligência em portadores de Neurofibromatose 1.

Bolini, Helenice Bianchi 27 October 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:35Z (GMT). No. of bitstreams: 1 helenicebianchibolini_tese.pdf: 2235516 bytes, checksum: 0e1ddb1957f1b10e0d67a793c7e4a245 (MD5) Previous issue date: 2010-10-27 / The practical problem observed referred to the clinical symptoms of NF1, involving intellectual performance and psychosocial characteristics of their carriers. This sends us to the NF1-intelligence interface. Objective: To identify and compare indices of intelligence and their frequencies in patients with NF1, attended at CEPAN. Methods and Casuistry: Medical records were used in research, semi-structured interview, the Wechsler Scales and Test Progressive Matrices Scale-General. Were applied indidually, to the 77 subjects, of which 30 patients with NF1, 17 family members, and 30 non- carriers between 2006 and 2010. The data were treated qualitative-quantitative. Results: The socioeconomic and cultural rights did not differ between subjects. Minors (<20 ) and larger (>20 ) time spent in the execution of Test Progressive Matrices Sacale-General were relatives of patients with NF1 and most were using medication. Mean correct responses were lower in patients with NF1, they had one and two symptoms that bothered when they were diagnosed, currently, the troubled portability three, four and two symptoms. Patients with NF1 had their first symptoms identified with more than five years age, they had relatives suffering from NF1 1st and/or 2nd degrees of relatedness (vertical transmission). They had mild MR and moderate, and learning disabilities. The subjects of this investigation showed TIQ; VIQ; TIQ/Gc; IOP/Gv; IVP/Gt average and below average; although the ability Reasoning/ Fluid Intelligence Gf category V. Conclusions: The subjects of this investigation have average and average lower, with limited sustainability. There are differences in intellectual performance among them: relatives of patients with NF1 are superior to the carriers and no- carriers are superior to both. There are mental retardation, learning disabilities, difficulties visual-perceptual-motor, memory impairments, and speech in written and spoken language in patients with NF1. There are no correlations between TIQ/Gc; IMO/Gsm; ICV/Gc; IOP/Gv; IVP/Gt and number of symptoms. There is no correlation between IQ, intellectual level, types, numbers, uncomfortable symptoms and age of onset of symptoms. / O problema prático observado, referiu-se aos sintomas clínicos de NF1, que envolviam o desempenho intelectual e as características psicossociais de seu portador, remetendo-nos à interface inteligência Neurofibromatose 1-NF1. Objetivo: Identificar e comparar os índices de inteligência e suas frequências em portadores de NF 1 atendidos no CEPAN. Casuística e Métodos: Utilizou-se pesquisa em prontuários; entrevista semi-estruturada; as Escalas de Wechsler e Testes de Matrizes Progressivas - Escala Geral, aplicados individualmente a 77 sujeitos, dos quais 30 portadores de NF1, 17 seus familiares e 30 não-portadores, entre 2006 e 2010. Os dados receberam tratamento quali-quantitativo. Resultados: As características socioeconômicas e culturais não diferiram entre os sujeitos Os tempos menores (<20 ) e maiores (>20 ) gastos na execução do Raven - Escala Geral foram de familiares e portadores de NF1, que mais faziam uso de medicação. As médias de acertos de portadores de NF1 foram as menores; possuíam 1 e 2 sintomas que os incomodavam quando foram diagnosticados; atualmente, era a portabilidade de 3, 4 e 2 sintomas que os incomodavam; primeiros sintomas identificados com mais de 5 anos; possuíam parentes portadores de NF1 de 1º e/ou 2º graus de parentesco (transmissão vertical); apresentaram RM leve e moderada; e distúrbio de aprendizagem (QI>70) em portadores de NF1. Os sujeitos dessa investigação apresentaram quocientes de inteligência e índices fatoriais médios e médio-inferiores; a capacidade Raciocínio/ Inteligência Fluida Gf encontrou-se comprometida-categoria V. Conclusões: Os sujeitos da investigação possuem inteligência média e média inferior, porém com dificuldade de sustentabilidade. Há diferenças de desempenho intelectual: familiares de portadores de NF1 são superiores aos portadores de NF1; e não portadores são superiores a ambos. Há retardo mental, distúrbio de aprendizagem, disfunção no desenvolvimento da linguagem dificuldades viso-motoras e perceptuais, deficiências de memória e de expressão na linguagem escrita e verbal em portadores de NF1; ausência de correlação entre QIT/Gc; IMO/Gsm; ICV/Gc; IOP/ Gv; IVP/ Gt e número de sintomas; e ausência de relação entre QI; nível intelectual; tipos; números; incômodos de sintomas e faixa etária do aparecimento dos primeiros sintomas.
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Evolution et facteurs pronostiques de la Neurofibromatose 1 / Factors Associated to Neurofibromatosis1

Sbidian, Émilie 23 October 2012 (has links)
La Neurofibromatose 1 (NF1) est une maladie autosomique dominante dont l’évolutivité est inconnue. En effet, ni le type de mutation du gène, la gravité d’éventuels cas familiaux, ni une première complication ne permettent de prédire le pronostic de la maladie. L’objectif général de ce travail de thèse était de cibler les malades les plus à risque de morbi-mortalité au cours de la NF1. Méthode. Les différents travaux se sont appuyés sur les données phénotypiques de patients NF1 suivis dans le Réseau NF-France labellisé par le ministère de la Santé. Il s’agit d’une filière nationale monothématique ayant pour mission la prise en charge des malades atteints de NF1. Une cohorte d’environ 2500 malades est actuellement suivie dans ce réseau. Résultats. La mortalité des patients NF1 a tout d’abord été comparée à celle de la population générale française par l’estimation du rapport de mortalité standardisée (SMR). Entre 1980 et 2006, 1 895 patients NF1 ont été rétrospectivement inclus dans la cohorte. Un excès de mortalité était observé chez les [10-20[ ans (SMR=5.2, IC95% : 2.6 – 9.3, p<10-4) et les [20-40[ ans (SMR=4.1, IC95% : 2.8 – 5.8, p<10-4). Les principales causes de décès étaient la transformation de neurofibromes internes en tumeurs malignes des gaines nerveuses (TMGN). Une étude cas témoins portant sur 208 patients NF1 a permis d’expliquer le risque de mortalité accru chez les patients présentant des neurofibromes sous cutanés (SC-NF) en confirmant en IRM la présence chez ces patients de neurofibromes internes à fort risque de transformation en TMGN (OR=4.3, IC95% : 2.2 – 8.2). Cet effet était d’autant plus marqué que le nombre de SC-NF était important et notamment au-delà d’un seuil de 10 (OR=82, IC95% : 10.4 – 647.9) et que les neurofibromes internes étaient diffus (OR=14.7, IC95% : 3.8 – 57.3) et de taille ≥ 3 cm (OR=6.3, IC95% : 2.3 – 17.4). Les patients présentant des SC-NF représentent 20 à 30% de la population NF1. Afin d’identifier les patients à risque de développer une TMGN, nous avons élaboré un score prédictif de la présence des neurofibromes internes à partir des caractéristiques phénotypiques des patients. La présence de SC-NF (OR=4.7, IC95% : 2.1 – 10.5), l’absence de neurofibromes cutanés (OR=2.6, IC95% : 0.9 – 7.5), un âge inférieur ou égal à 30 ans (OR=3.1, IC95% : 1.4 – 6.8) et moins de 6 tâches café au lait (OR=2, IC95% : 0.9 – 4.6) étaient les variables qui constituaient le NF1Score. Le NF1Score = 10*(âge ≤ 30 ans) + 10*(absence de neurofibromes cutanés) + 5*(moins de 6 tâches café-au-lait) + 15*(plus de 2 neurofibrome sous cutanés) avait une excellente adéquation (test C de Hosmer-Lemeshow=4,53 avec 7ddl, p>0,50) et une capacité discriminante satisfaisante (aire sous la courbe ROC non paramétrique = 0,75 [0,68-0,82]). Enfin, l’expression phénotypique variant au cours du temps chez un même patient nous avons réalisé une étude spécifique chez l’enfant. Ainsi, l’âge (OR=1.1, IC95% : 1.0 – 1.2), la présence de xanthogranulomes (OR=4.5, IC95% : 0.9 – 21.7), celle de neurofibromes sous cutanés et plexiformes (OR=5.0, IC95% : 1.8 – 13.6) étaient indépendamment associés à celle des neurofibromes internes chez l’enfant NF1 de moins de 17 ans. Dans cette dernière étude, les neurofibromes internes se développaient de façon exponentielle pendant l’adolescence et plus précocement chez les femmes en accord avec les données de la littérature. Conclusion. La période à risque de développer des neurofibromes internes semblent donc sesituer entre l’adolescence et l’âge de 30 ans. Les recommandations de suivi pourraient prendre en compte le phénotype à risque, mais également la période de survenue de ces complications en réévaluant l’intérêt dans ce contexte d’investigations complémentaires / Neurofibromatosis-1 (NF1) is a common autosomal dominant condition which is a source of various multisystemic manifestations related either to the accumulation of neurofibromas or to specific developmental abnormalities. There are no obvious factors that predict disease progression. Thus, the aim of our project was to characterize the phenotype of NF1 patients with a severe prognosis. Patients were identified among adults with NF-1 followed up in the Réseau NF-France. The Réseau NF-France is a French medical network devoted to neurofibromatosis 1. It has elaborated recommendations for the management of the disease and recommended a coordinated follow-up in specialized multidisciplinary centres. About 2 500 patients were enrolled. We first evaluated the mortality in a large retrospective cohort of NF1 patients. The standardized mortality ratio (SMR) with its 95% confidence interval (CI) was calculated as the ratio of observed over expected numbers of deaths. Between 1980 and 2006, 1895 NF1 patients were seen. The excess mortality occurred among patients aged 10 to 20 years (SMR=5.2; CI, 2.6-9.3; P<10-4) and 20 to 40 years (SMR, 4.1; 2.8-5.8; P<10-4). The main cause of death was the malignant tumors of the nerve sheath (MPNSTs) developing from preexisting internal neurofibromas. Then, a case-control study including 208 patients with NF1 allowed us to explain the increased risk of mortality among NF1 patients harboring subcutaneous neurofibromas (SC-NF) by the presence of internal neurofibromas (NF) at risk of MPNSTs systematically investigated with imaging (MRI) (OR=4.3, IC95% : 2.2 – 8.2). The association with SC-NF was stronger for patients with ten or more SC-NFs (OR=82, IC95% : 10.4 – 647.9) and for diffuse (OR=14.7, IC95% : 3.8 – 57.3), and ≥ 3 cm (OR=6.3, IC95% : 2.3 – 17.4) internal neurofibromas. Patients with SC-NF constituted 20 to 30% of the NF1 population. So, to characterize patients at risk of developping MPNSTs, we developped and validated a clinical score for predicting internal neurofibromas in adults. Four variables were independently associated with internal neurofibromas: at least two subcutaneous neurofibromas (OR=4.7, IC95% : 2.1 – 10.5), age ≤30 years (OR=3.1, IC95% : 1.4 – 6.8), absence of cutaneous neurofibromas (OR=2.6, IC95% : 0.9 – 7.5), and fewer than six café-au-lait spots (OR=2, IC95% : 0.9 – 4.6). The NF1Score was computed as 10 . [age ≤30 years] + 10 • [absence of cutaneous neurofibromas] + 15 • [≥2 subcutaneous neurofibromas] + 5 • [<6 café-au-lait spots]). Calibration was excellent (Hosmer-Lemeshow statistic=4.53; degrees of freedom=7; P>0.5) and discrimination was good (AUC-ROC= 0.75; 95%CI, 0.7-0.8). Finally clinical expressivity is variable and manifestations of NF1 change at different times in an individual’s life. Consequently, a specific study was needed in pediatric patients. We identified easily recognizable clinical characteristics associated with internal neurofibromas in children with NF1. By multivariate analysis, age (OR=1.1, IC95% : 1.0 – 1.2), xanthogranulomas (OR=4.5, IC95% : 0.9 – 21.7), and presence of both subcutaneous and plexiform neurofibromas (OR=5.0, IC95% : 1.8 – 13.6) were independently associated with internal neurofibromas. Moreover internal neurofibromas increased during adolescence. Excess risk of developing internal neurofibromas seems to occur between the adolescence and the age of to 30 in NF1 patients. These clinical features in adults and children would define a new population at risk for complications that may need closer clinical and imaging follow-up

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