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Implication de Syngap1 dans la transmission GABAergique et la plasticité synaptiqueXing, Paul 08 1900 (has links)
La déficience intellectuelle affecte de 1 à 3% de la population mondiale, ce qui en fait le trouble cognitif le plus commun de l’enfance. Notre groupe à découvert que des mutations dans le gène SYNGAP1 sont une cause fréquente de déficience intellectuelle non-syndromique, qui compte pour 1-3% de l’ensemble des cas. À titre d’exemple, le syndrome du X fragile, qui est la cause monogénique la plus fréquente de déficience intellectuelle, compte pour environ 2% des cas. Plusieurs patients affectés au niveau de SYNGAP1 présentent également des symptômes de l’autisme et d’une forme d’épilepsie. Notre groupe a également montré que SYNGAP1 cause la déficience intellectuelle par un mécanisme d’haploinsuffisance. SYNGAP1 code pour une protéine exprimée exclusivement dans le cerveau qui interagit avec la sous-unité GluN2B des récepteurs glutamatergique de type NMDA (NMDAR). SYNGAP1 possède une activité activatrice de Ras-GTPase qui régule négativement Ras au niveau des synapses excitatrices.
Les souris hétérozygotes pour Syngap1 (souris Syngap1+/-) présentent des anomalies de comportement et des déficits cognitifs, ce qui en fait un bon modèle d’étude. Plusieurs études rapportent que l’haploinsuffisance de Syngap1 affecte le développement cérébral en perturbant l’activité et la plasticité des neurones excitateurs. Le déséquilibre excitation/inhibition est une théorie émergente de l’origine de la déficience intellectuelle et de l’autisme. Cependant, plusieurs groupes y compris le nôtre ont rapporté que Syngap1 est également exprimé dans au moins une sous-population d’interneurones GABAergiques. Notre hypothèse était donc que l’haploinsuffisance de Syngap1 dans les interneurones contribuerait en partie aux déficits cognitifs et au déséquilibre d’excitation/inhibition observés chez les souris Syngap1+/-.
Pour tester cette hypothèse, nous avons généré un modèle de souris transgéniques dont l’expression de Syngap1 a été diminuée uniquement dans les interneurones dérivés des éminences ganglionnaires médianes qui expriment le facteur de transcription Nkx2.1 (souris Tg(Nkx2,1-Cre);Syngap1). Nous avons observé une diminution des courants postsynaptiques inhibiteurs miniatures (mIPSCs) au niveau des cellules pyramidales des couches 2/3 du cortex somatosensoriel primaire (S1) et dans le CA1 de l’hippocampe des souris Tg(Nkx2,1-Cre);Syngap1. Ces résultats supportent donc l’hypothèse selon laquelle la perte de Syngap1 dans les interneurones contribue au déséquilibre d’excitation/inhibition. De manière intéressante, nous avons également observé que les courants postsynaptiques excitateurs miniatures (mEPSCs) étaient augmentés dans le cortex S1, mais diminués dans le CA1 de l’hippocampe.
Par la suite, nous avons testé si les mécanismes de plasticité synaptique qui sous-tendraient l’apprentissage étaient affectés par l’haploinsuffisance de Syngap1 dans les interneurones. Nous avons pu montrer que la potentialisation à long terme (LTP) NMDAR-dépendante était diminuée chez les souris Tg(Nkx2,1-Cre);Syngap1, sans que la dépression à long terme (LTD) NMDAR-dépendante soit affectée. Nous avons également montré que l’application d’un bloqueur des récepteurs GABAA renversait en partie le déficit de LTP rapporté chez les souris Syngap1+/-, suggérant qu’un déficit de désinhibition serait présent chez ces souris.
L’ensemble de ces résultats supporte un rôle de Syngap1 dans les interneurones qui contribue aux déficits observés chez les souris affectées par l’haploinsuffisance de Syngap1. / Intellectual disability affects 1-3% of the world population, which make it the most common cognitive disorder of childhood. Our group discovered that mutation in the SYNGAP1 gene was a frequent cause of non-syndromic intellectual disability, accounting for 1-3% of the cases. For example, the fragile X syndrome, which is the most common monogenic cause of intellectual disability, accounts for 2% of all cases. Some patients affected by SYNGAP1 also showed autism spectrum disorder and epileptic seizures. Our group also showed that mutations in SYNGAP1 caused intellectual disability by an haploinsufficiency mechanism. SYNGAP1 codes for a protein expressed only in the brain which interacts with the GluN2B subunit of NMDA glutamatergic receptors (NMDAR). SYNGAP1 possesses a Ras-GAP activating activity which negatively regulates Ras at excitatory synapses.
Heterozygote mice for Syngap1 (Syngap1+/- mice) show behaviour abnormalities and learning deficits, which makes them a good model of intellectual disability. Some studies showed that Syngap1 affects the brain development by perturbing the activity and plasticity of excitatory neurons. The excitatory/inhibitory imbalance is an emerging theory of the origin of intellectual disability and autism. However, some groups including ours, showed that Syngap1 is expressed in at least a subpopulation of GABAergic interneurons. Therefore, our hypothesis was that Syngap1 happloinsufficiency in interneurons contributes in part to the cognitive deficits and excitation/inhibition imbalance observed in Syngap1+/- mice.
To test this hypothesis, we generated a transgenic mouse model where Syngap1 expression was decreased only in GABAergic interneurons derived from the medial ganglionic eminence, which expresses the transcription factor Nkx2.1 (Tg(Nkx2,1-Cre);Syngap1 mouse). We showed that miniature inhibitory postsynaptic currents (mIPSCs) were decreased in pyramidal cells in layers 2/3 in primary somatosensory cortex (S1) and in CA1 region of the hippocampus of Tg(Nkx2,1-Cre);Syngap1 mice. Those results suggest that Syngap1 haploinsufficiency in GABAergic interneurons contributes in part to the excitation/inhibition imbalance observed in Syngap1+/- mice. Interestingly, we also observed that miniature excitatory postsynaptic currents (mEPSCs) were increased in cortex S1 but decreased in CA1 region of the hippocampus.
We further tested whether synaptic plasticity mechanisms that are thought to underlie learning and memory were affected by Syngap1 haploinsufficiency in GABAergic interneurons. We showed that NMDAR-dependent long-term potentiation (LTP) but not NMDAR-dependent long-term depression (LTD) was decreased in Tg(Nkx2,1-Cre);Syngap1 mice. We also showed that GABAA receptor blockade rescued in part the LTP deficit in Syngap1+/- mice, suggesting that a disinhibition deficit is present in these mice.
Altogether, the results support a functional role of Syngap1 in GABAergic interneurons, which may in turn contributes to the deficit observed in Syngap1+/- mice.
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Étude exploratoire des transitions de milieux de vie en communauté des personnes présentant une déficience intellectuelleLongtin, Véronique 09 1900 (has links)
Cette étude exploratoire dresse un portrait des transitions de milieux de vie (MDV) dans des Centres de réadaptation en déficience intellectuelle et en troubles envahissants du développement (CRDITED) de la grande région de Montréal. Elle permet d’identifier 1) les pratiques de transition de MDV des intervenants pivots en CRDITED, 2) les critères de succès de la transition de MDV et les moyens de les évaluer selon les personnes présentant une déficience intellectuelle et les intervenants pivots et 3) l’écart entre les pratiques souhaitées et les pratiques actuelles à partir du point de vue des deux types de participants. Des personnes présentant une déficience intellectuelle (N = 9) et des intervenants pivots (N = 19) se sont exprimés sur leurs expériences de transition de MDV en participant à des entretiens de groupe.
Une analyse qualitative de contenu a permis d’identifier une typologie des expériences de transition de MDV du point de vue des intervenants pivots. Un seul type de transition de MDV parmi les cinq identifiés, le type préparée, offre des conditions favorisant la réalisation de la transition dans des conditions satisfaisantes pour les intervenants pivots. Les autres types de transitions (types dernière minute, explosive, clé en main et salle d’attente) offrent peu d’occasions pour la personne présentant une déficience intellectuelle de s’impliquer dans le processus de transition. Les propos des intervenants pivots permettent d’identifier les caractéristiques d’une transition de MDV qu’ils jugent idéale (type comme si c’était moi). Les types de transitions sont comparés entre eux sur deux axes, soit sur l’axe représentant un continuum d’implication de la personne présentant une déficience intellectuelle dans sa propre transition et sur l’axe identifiant les grandes étapes de réalisation de la transition. Les résultats permettent de déceler un écart important entre les transitions actuellement effectuées et les politiques, intentions et engagements de l’offre de service auprès de cette clientèle, notamment au regard de l’implication de la personne présentant une déficience intellectuelle dans les décisions relatives à sa transition de MDV.
L’étude permet aussi d’identifier trois dimensions importantes de l’évaluation du succès de la transition selon les perspectives des personnes présentant une déficience intellectuelle et des intervenants pivots. Les dimensions identifiées sont : bien-être psychologique et comportement, santé physique et collaboration. Les propos des intervenants pivots permettent de constater qu’il existe parfois un paradoxe entre leurs perceptions du succès de la transition de MDV et celles des personnes présentant une déficience intellectuelle. L’interprétation des résultats a permis d’élaborer des recommandations afin de favoriser de meilleures pratiques de transition. / This exploratory study provides a portrait of community living transitions in rehabilitation centers for intellectual disabilities and pervasive developmental disorders (CRDITED) in the greater Montreal region. It identifies: 1) the practices of community living transitions in CRDITED, 2) the success criteria of the community living transitions and ways to evaluate them according to people with intellectual disabilities and educators, and 3) the difference between the desired practices and current practices from the viewpoint of both respondents. People with intellectual disabilities (N = 9) and educators (N = 19) spoke about their experiences of community living transitions in group interviews.
Qualitative content analysis has identified a typology of community living transitions from the educators’ point of view. One out the five types of transitions offers favorable conditions for a transition under satisfactory criteria for educators (prepared). Other types of transitions (last minute, explosive, turnkey, waiting room) offer little opportunity for the person with intellectual disabilities to get involved in the transition process. Educators identify characteristics of an ideal community living transition (as if it was me). All types of transitions are compared with each other based on transition steps and on the involvement level of the person with intellectual disabilities. A difference between the currently performed transitions and policy intentions and commitments was identified, particularly with regard to the involvement of the person in decisions on its own community living transition.
The study also identified three important transition success dimensions from the perspective of both respondents: psychological well-being and behavior, physical health, and collaboration. The results disclose that there is sometimes a paradox in community living transition success perceptions between educators and people with intellectual disabilities. Interpretation of the results helped develop recommendations to promote better community living transition practices.
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Functional genomics analyses of neuropsychiatric and neurodevelopmental disordersSteinberg, Julia January 2014 (has links)
Recent large-scale genome-wide studies for many human disorders have identified associations with numerous genetic variants. The biological interpretation of these variants presents a major challenge. In particular, the identification of biological pathways underlying the association could provide crucial insights into the disease aetiologies. In this thesis, I used functional genomics approaches to increase our understanding of neuropsychiatric and neurodevelopmental disorders. Firstly, in an integrative analysis of autism spectrum disorder (ASD), I looked into the role of genes targeted by Fragile-X Mental Retardation Protein ("FMRP targets"). I found evidence that FMRP targets contribute to ASD via two distinct aetiologies: (1) ultra-rare and highly penetrant single disruptions of embryonically upregulated FMRP targets ("single-hit aetiology") or (2) the combination of multiple less penetrant disruptions of synaptic FMRP targets ("multiple-hit aetiology"). In particular, I developed a pathway-association test sensitive to multiple-hit aetiologies. Secondly, I carried out an integrative analysis of bipolar disorder, following up a previously identified association with long-term potentiation. The association was not consistent across independent SNP and CNV datasets. Thirdly, I addressed the difficulty in identifying functional relationships between genes by integrating different datasets into a gene functional-linkage network tuned to the nervous system ("NsNet"). NsNet identified functional links between the genes disrupted by de novo loss-of-function mutations in ASD and, separately, in schizophrenia probands more sensitively than a general functional-linkage network. Fourthly, I considered the challenge of interpreting the phenotypic impact of gene disruptions, focusing on the identification of haploinsufficient genes. I constructed a gene haploinsufficiency score based on genome-wide datasets. Compared to existing approaches, the new score performed better in identifying less-studied haploinsufficient genes. This work both extends the methodology to detect the contribution of genetic variation to neuropsychiatric disorders and also yields insights into the variant genes and the pathways that underlie them. Firstly, in an integrative analysis of autism spectrum disorder (ASD), I looked into the role of genes targeted by Fragile-X Mental Retardation Protein ("FMRP targets"). I found evidence that FMRP targets contribute to ASD via two distinct aetiologies: (1) ultra-rare and highly penetrant single disruptions of embryonically upregulated FMRP targets ("single-hit aetiology") or (2) the combination of multiple less penetrant disruptions of synaptic FMRP targets ("multiple-hit aetiology"). In particular, I developed a pathway-association test sensitive to multiple-hit aetiologies. Secondly, I carried out an integrative analysis of bipolar disorder, following up a previously identified association with long-term potentiation. The association was not consistent across independent SNP and CNV datasets. Thirdly, I addressed the difficulty in identifying functional relationships between genes by integrating different datasets into a gene functional-linkage network tuned to the nervous system ("NsNet"). NsNet identified functional links between the genes disrupted by de novo loss-of-function mutations in ASD and, separately, in schizophrenia probands more sensitively than a general functional-linkage network. Fourthly, I considered the challenge of interpreting the phenotypic impact of gene disruptions, focusing on the identification of haploinsufficient genes. I constructed a gene haploinsufficiency score based on genome-wide datasets. Compared to existing approaches, the new score performed better in identifying less-studied haploinsufficient genes. This work both extends the methodology to detect the contribution of genetic variation to neuropsychiatric disorders and also yields insights into the variant genes and the pathways that underlie them.
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Zaměstnávání osob s lehkou mentální retardací na Kladensku / Employment of Persons Suffering from Mild Intellectual Disability in Kladno regionKlemperová, Aneta January 2015 (has links)
The aim of this thesis is to analyse employment of people suffering from mild intellectual disability. The thesis briefly describes those learning difficulties and selects a mild intellectual disability from a wide range of other mental disabilities. The text is based on the fact that people with learning difficulties are able to work, live in a family and become members of the society as well as to be independent citizens. However, there is a necessity to help those people not only with regard to their educational process, but also on the labour market, which is apparently highly competitive even for people without any special needs. The thesis is also focused on various possibilities of people suffering from learning difficulties in the terms of enabling them to get a job. In accordance with the regulation on mild intellectual disability people, the thesis suggests many of suitable positions within service industry. Owing to the fact that people with this type of disease are under protection of the law, and that there are some incentives for employers, nowadays it is much easier to find them a job. Among other things, the thesis is also focused on economic, sociological and psychological aspects, so far as finding and keeping a job. For all people, their integration into society through the work...
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Rozvoj čtenářské gramotnosti u žáků s lehkým mentálním postižením / Development of the reading literacy of children with mild mental disabilitiesKobesová, Alena January 2016 (has links)
The theme of this diploma thesis is the development of literacy of pupils with mild intellectual disability. This thesis is divided into 5 parts. The key words such as literacy, reading literacy, pupil with a mild intellectual disability and schooling of pupils with mild intellectual disability, are described in the first four parts. Chapter number five is the empirical part of the thesis. The aim of this thesis is to find out the level of the reading literacy of pupils with mild intellectual disability at the school for mentally retarded children. A handbook supporting the development of the reading literacy for pupils with mild intellectual disability has been written based on this result. Methods of quantitative research have been used to obtain the final results. One of the research instruments was also a nonofficial test of reading literacy that has for its purpose to determine the level of the reading literacy of mildly mentally disabled pupils. KEYWORDS pupil, literacy, reading literacy, reading literacy test, mild intellectual disability, school for mild mentally retarded pupils
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"Det viktiga är ju att man tror att dom kan" : En fenomenografisk studie av lärares uppfattningar av läsundervisning på träningsskolanEhlin, Annika January 2017 (has links)
Syftet med denna studie är att undersöka och beskriva variationer av lärarnas uppfattningar om läsundervisning i grundsärskolan. Den valda metoden för studien är fenomenografi. En fenomenografisk studie beskriver hur människor uppfattar ett fenomen i sin miljö. Sex lärare som för närvarande arbetar med läsundervisning i grundsärskolan har intervjuats. En fenomenografisk analys i sex steg har använts för att analysera intervjuerna. Resultatet i studien redovisas i tre olika utfallsrum. I utfallsrummen beskrivs lärares uppfattningar av sitt ansvar, lärares uppfattningar av god läsundervisning och lärares uppfattningar av utmaningar i grundsärskolan. Slutligen beskriver denna studie hur lärare uppfattar sitt uppdrag, vad de anser vara viktiga inslag i läsundervisning och hur lärare uppfattar elevernas förmåga att lära sig läsa. En viktig slutsats är att de intervjuade lärarna anser att det är viktigt att tro på elevers förmåga att lära sig att läsa. En annan slutsats är att undervisningen bör planeras utifrån elevers intressen. Nuvarande forskning om lärares läsundervisning har diskuterats liksom om läroplanen främjar elevers läsutveckling. / The purpose of this study is to examine and describe variations of teachers' perceptions of readinginstruction in the compusory school for pupils with learning disabilities. The chosen method of the study is phenomenography. A phenomenographical study describes how people perceive a phenomenon in their environment. Six teachers currently working with reading instruction in the compusory school for pupils with learning disabilities have been interviewed. A six-step phenomenographical approach has been used to analyze the interviews. The results of the study are reported in three different outcome spaces. In the outcome spaces describes the teachers’ perceptions of their responsibility, teachers’ perceptions of good reading instruction and teachers' perception of challenges in the compusory school for pupils with learning disabilities. Finally this study describes how teachers perceive their mission, what they deem as key elements of reading instruction and how teachers perceive students' ability to learn to read. An important conclusion is that the interviewed teachers mean that it is important to believe in pupils' ability to learn to read. Another conclusion is that they also favor work planned around student's interests. Current research on teachers´ reading instruction are discussed as well as if the curriculum directing today's training school promotes students reading skills.
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Allt hänger ju ihop : Lärares förståelse om lärmiljöns betydelse för utveckling av elevers kommunikativa och sociala delaktighet i grundsärskolan, inriktning ämnesområdenNilsson Sandberg, Maria January 2019 (has links)
No description available.
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Social delaktighet för elever som läser i grundsärskolan med inriktning ämnesområden : En uppsats om elevassistenters tankar om hur elevers sociala delaktighet kan stärkas / Social participation for learners in the compulsory school for pupils with learning disabilities : An essay about educational aid`s thoughts on strengthening pupils’social participationLundvall, Katarina January 2019 (has links)
The purpose of this study is to examine educational aid´s perceptions of social inclusion in the compulsory school for pupils with learning disabilities in training school classes. The chosen method of this study is a qualitive research approach. Five educational aid´s currently working with pupils with intellectual disabilities in the compulsory school for pupils with learning disabilities have been interviewed. A relational and categorical models of special education has been used to analyze the interviews and a comparison between the relational, categorical approach, the thoughts of the educational aids and the regulatory documents from the Swedish National Agency for Education is taking place in the study. The result of the study shows that most of the educational aid´s in the study thinks that they can both support and obstruct social inclusion for pupils with learning disabilities. The study also shows that pedagogical guidance and discussions in the work crew about social inclusion are important to promote social inclusion. The educational aid´s believe that the pupils have little interest in participate in social interaction with other pupils. Furthermore the paraprofessionals believe that the teachers should have a comprehensive view over the pupils and their school day and that the educational aid´s thinks that they have a closer relation with the pupils because they spend more time with them than the teachers do. The informants indicated that learning environments, the ability to back away, and cooperation within the teaching team are important factors to promote social inclusion. / Syftet med studien är att undersöka några elevassistenters uppfattningar om social delaktighet i grundsärskolan med inriktning mot ämnesområden. Den valda metoden i denna studie var en kvalitativ forskningsansats. Fem elevassistenter som arbetar med elever i grundsärskolan med inriktning mot ämnesområden har blivit intervjuade. En relationell och kategorisk modell av specialundervisning har använts för att analysera intervjuerna och en jämförelse mellan det relationella, kategoriska synsättet, tankar från elevassistenterna och Skolverkets styrdokument sker i denna studie. Resultatet visade att merparten av elevassistenterna ansåg att de själva både kunde underlätta oh vara till hinder för den sociala delaktigheten för elever med utvecklingsstörning. Att handledning och diskussion om social delaktighet var viktiga faktorer samt att elevassistenterna ansåg att elever med utvecklingsstörning själva hade ett begränsat intresse av att inleda socialt samspel med andra elever. Studien visade även att pedagogisk handledning och diskussioner inom arbetslaget om social delaktighet är viktiga faktorer för att öka social delaktighet. Elevassistenterna ansåg att eleverna hade lågt intresse av att delta i sociala interaktioner med andra elever. Vidare så framhöll elevassistenterna att en lärare bör ha ett helhetsgrepp över eleverna och undervisningen och elevassistenterna anser att de har en närmare relation med eleverna då de spenderar mer tid med dem än vad lärarna. Elevassistenterna indikerade att lärmiljö, förmåga att backa undan och samverkan inom arbetslaget som viktiga faktorer för att öka social delaktighet.
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Investigação da variação no número de cópias genômicas (CNVs) em pacientes com anomalias congênitas e atraso de desenvolvimento neuropsicomotor (ADNPM) pela técnica de MLPA (Multiplex Ligation-dependent Probe Amplification) / Investigation of the copy number variation (CNVs) in patients with congenital anomalies (CA) and mental retardation (MR) using the MLPA (Multiplex Ligation-dependent Probe Amplification) techniqueDutra, Roberta Lelis 04 September 2014 (has links)
INTRODUÇÃO: Os desequilíbrios genômicos constituem causa frequente de abortamento, anomalias congênitas (AC) e atraso de desenvolvimento neuropsicomotor (ADNPM). O aprimoramento de novas técnicas de diagnóstico citogenômico, como por exemplo, a MLPA (Multiplex Ligation-dependent Probe Amplification) e a triagem ampla do DNA utilizando arrays, mostraram que a alteração no número normal de cópias genômicas (CNVs) influencia na patogenicidade dos fenótipos em diversas síndromes. OBJETIVOS: Com isso, os objetivos do presente estudo foram identificar CNVs em pacientes com MC e ADNPM utilizando a técnica de MLPA e, a partir dos resultados alterados, aplicar da técnica de array para a identificação de possíveis rearranjos complexos, além de associar as alterações moleculares encontradas com o fenótipo dos pacientes. MÉTODOS: Participaram do estudo 416 pacientes com MC e ADNPM. As amostras de DNA foram analisadas utilizando a técnica de MLPA com kits comerciais para as principais síndromes de microdeleções (P064) e regiões subteloméricas (P036 e P070). Dois kits de MLPA específicos para as regiões 7q11.23 (P029) e 22q11.2 (P250) também foram utilizados para complementar a identificação de CNVs atípicas. Entre os casos que apresentavam alterações pela técnica de MLPA, 15 pacientes foram submetidos à técnica de array, utilizando três diferentes plataformas: Agilent SurePrint G3 Genoma Humano microarray 180 K, HumanCytoSNP-12 BeadChip, CytoScan(TM) HD array 6.0 Affymetrix®. RESULTADOS: A análise molecular pela técnica de MLPA possibilitou a detecção de microdeleções e/ou microduplicações em 97 pacientes sendo que: em 46 pacientes foi possível encontrar alterações utilizando apenas o kit P064 (microdeleções), em 34 pacientes utilizando apenas os kits P036 e P070 (regiões subteloméricas) e em quatro pacientes só foi possível identificar a alteração utilizando outro kit de MLPA (P250), específico para alterações genômicas em 22q11.2. Rearranjos complexos, envolvendo mais de três cromossomos, foram observados em 10 pacientes. DISCUSSÃO: A MLPA permitiu detectar CNVs em 97/416 pacientes (23,3%), sendo uma técnica ideal para ser aplicada em pacientes com sinais fenotípicos inespecíficos. Algumas alterações genômicas encontradas estão relacionadas também com alterações específicas, como a presença de malformação cardíaca ou convulsões. E em outros casos a alta variabilidade fenotípica pode ser associada a um conjunto de CNVs consideradas patogênicas. Além disso, a inclusão de outra técnica de triagem, com maior cobertura do genoma permitiu detectar rearranjos complexos antes não observados mesmo em síndromes bem descritas como as síndromes de midrodeleções 7q11.23 e 22q11.2. CONCLUSÃO: A MLPA com kits combinados, por possuir maior abrangência de regiões detectadas e menor custo, é uma ferramenta valiosa para ser utilizada como um teste de triagem diagnóstica / INTRODUCTION: Genomic imbalances are the most common cause of miscarriage, congenital anomalies (CA) and mental retardation (MR). With the improvement of new cytogenomics diagnostic techniques, such as the MLPA (Multiplex Ligation-dependent Probe Amplification) and the array techniques, it have been shown that changes in the normal gene copy number influence the pathogenic variability of phenotypes in different syndromes. AIMS: The aims of the present study were to identify CNVs in patients with CM and RM using the MLPA technique and, from the abnormalities results, to apply the array methodology for the identification of complex rearrangements. Furthermore, the study aimed to associate the alterations found by molecular techniques with the phenotype of patients. METHODS: 416 patients with CM and RM participated in the study. The samples were analysed by MLPA technique with commercial kits for the main microdeletion syndromes (P064) and subtelomeric regions (P036 and P070). Two more MLPA kits for specific regions 7q11.23 (P029) and 22q11.2 (P250) were used to confirm the altered results and to complement some results with the identification of atypical abnormalities. From the patients who presented abnormalities by MLPA technique, 15 underwent by microarray-based comparative genomic hybridization (CGH-array) technique, using three different platform: Agilent SurePrint G3 Human Genome microarray 180 kb, HumanCytoSNP -12 BeadChip, CytoScan(TM) HD ® and Affymetrix 6.0. RESULTS: The molecular analysis by MLPA technique allowed the detection of microdeletions and/or microduplications in 97 patients. In 46 patients it was possible to find genomic alteration using only MLPA kit P064 and in 34 patients using only the subtelomeric kits P036 and P070. For four patients it was only possible to identify the genomic abnormalities using another specific MLPA kit (P250), involving the 22q11.2 region. Complex rearrangements involving more than three chromosomes were detected in 10 patients. DISCUSSION: The MLPA technique was capable of detecting CNVs in 97/416 (23,3%) of patients, being an ideal technique to be applied in patients with non-specific signs phenotypic. Some genomic alterations found are, also related to specific changes, such as the presence of cardiac malformation or convulsions. In other cases, the high phenotypic variability may be associated to certain group of pathogenic CNVs. Moreover, the inclusion of additional screening method, with greater coverage, allowed the detection of complex rearrangements not seen before even in syndromes as well described microdeletions syndromes on 7q11.23 and 22q11.2 regions. CONCLUSION: The MLPA technique can be a valuable tool used as a molecular screening test, because it has greater coverage and lower cost of detected regions
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Prevalência de escoliose em pacientes com síndrome de Williams-Beuren / Prevalence of scoliosis in patients with the Williams-Beuren syndromeDamasceno, Marcelo Loquette 16 July 2013 (has links)
Introdução: A síndrome de Williams-Beuren (SWB) consiste de uma deleção no cromossomo 7q11.23, região responsável pela codificação de 28 genes, estando o gene codificador da elastina situado aproximadamente no ponto médio dos extremos da deleção; a mutação no gene da elastina leva a alterações fenotípicas no paciente, com prejuízo do desenvolvimento neuropsicomotor de graus variados, fáscies características, anormalidades cardiovasculares, hipercalcemia, disfunções urológicas e osteoarticulares. O presente estudo avaliou a prevalência de escoliose em pacientes com diagnóstico de SWB, bem como sua relação com o padrão das curvas nos portadores de escoliose. Métodos: Foram incluídos 41 pacientes com diagnóstico de SWB através da realização de anamnese, exame físico e investigação radiográfica, sendo 25 do sexo masculino. Realizou-se a interpretação das radiografias e obtenção do ângulo de Cobb. Resultados: Observou-se que 14 pacientes eram portadores de escoliose, sendo 10 do sexo masculino. O padrão da deformidade apresentou-se, nos pacientes mais jovens, através de curvas simples e flexíveis, e, apesar de adultos apresentarem ocorrência de duplas curvas e triplas curvas, a análise estatística não evidenciou relação entre escoliose e idade ou sexo dos pacientes. Conclusões: O estudo evidenciou prevalência de escoliose em portadores de SWB: 34,1%; entretanto, as variáveis idade e sexo não apresentaram relação com a ocorrência de escoliose, assim como a gravidade das curvas apresentadas / Introduction: Williams-Beuren syndrome (WBS) consists of a chromosome 7q11.23 deletion in the region responsible for encoding 28 genes, with the elastin encoding gene situated approximately at the midpoint of the extremes of deletion; mutation of the elastin gene leads to phenotypic changes in patients with neurodevelopment impairment of varying degrees, characteristic facies, cardiovascular abnormalities, hypercalcemia, and urological and bone and joint dysfunctions. This study assessed the prevalence of scoliosis in patients with WBS, and the relationship with the pattern of scoliotic curves. Methods: A total of 41 patients diagnosed with SWB were included in the study, 25 males, through anamnesis, physical examination and radiographic investigation. Radiographic imaging was interpreted and the Cobb angle was calculated. Results: It was observed that 14 patients had scoliosis, and 10 of them were male. The pattern of the deformity in younger patients was of flexible and simple curves, and although adults presented double and triple curves, statistical analysis showed no relationship between scoliosis and age or sex. Conclusion: The study revealed a prevalence of scoliosis in patients with SWB of 34.1%; however, the variables age and sex had were not significantly associated with scoliosis, nor with the severity of the curves
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