Made available in DSpace on 2016-12-23T13:49:03Z (GMT). No. of bitstreams: 1 Lorena Schneider Almeida.pdf: 683869 bytes, checksum: 550e76756dab14ae47e0e2440cfba6ca (MD5) Previous issue date: 2013-02-28 / The Osteogenesis Imperfecta (OI) is a genetic disease characterized by structural defects of type I collagen protein or by reducing its biosynthesis causing decreased bone mass and predisposition to fractures and bone deformities. Approximately 90% of individuals with OI exhibit autosomal dominant inheritance caused by mutations in the genes COL1A1 and COL1A2. However, the number of genes linked to autosomal recessive forms of OI is increasing in the literature. The CRTAP gene was the second identified causing recessive inheritance OI. This gene has 6622 bp, seven exons and encodes a protein of 46.5 kDa. The CRTAP encoding the protein cartilage associated (CRTAP) which is part of the collagen 3-hydroxylation complex, responsible for post-translational modifications during the biosynthesis of collagen molecule. CRTAP mutations are related to severe and lethal form of the disease. The target of this research was evaluating the exons of CRTAP and its adjacent regions in OI patients from Espírito Santo thought the Single-Stranded Conformation Polymorphism (SSCP) screening of mutations and sequencing. We studied 24 patients with clinical diagnosis of OI from Hospital Infantil Nossa Senhora da Glória de Vitória, Brazil. The patients/ ages ranged from 2 to 16 years (median: 14.5). The sex proportion of the patients was 15 males and 9 females. Eleven patients have mild clinical symptoms of the disease, 5 show moderate symptoms and 9 were severe cases. The lethal OI cases were not obtained by methodological difficulties. We found the polymorphisms c.534C> T previously reported in exon 2 of the CRTAP gene in patients from sample. No pathogenic mutations were found in this study. The results of this study suggest that mutations in CRTAP are rare in ES population. These data may assist in developing more efficient methodological strategies for molecular diagnosis of OI / A Osteogênese Imperfeita (OI) é uma doença genética caracterizada por defeitos estruturais da proteína do colágeno tipo I ou por redução da sua biossíntese causando diminuição da massa óssea e a predisposição a fraturas e deformidades ósseas. Aproximadamente 90% dos indivíduos com OI apresentam herança autossômica dominante causada por mutações nos genes COL1A1 ou COL1A2. Contudo, é crescente o número de genes ligados à herança autossômica recessiva da OI descritos na literatura. O gene CRTAP foi o segundo gene identificado causando OI com herança recessiva. Este gene possui 6.622 pb, 7 exons e codifica uma proteína de 46,5 KDa. O gene CRTAP codifica a proteína da cartilagem associada (CRTAP) que faz parte do complexo prolil 3-hidroxilação, responsável por modificações pós-traducionais fundamentais durante a biossíntese da molécula de colágeno. Mutações no gene CRTAP estão relacionadas à forma grave ou letal da doença. Esta pesquisa teve como objetivo avaliar as porções codificantes do gene CRTAP e suas regiões adjacentes em pacientes com OI do estado do Espírito Santo por meio da técnica de triagem de mutações de Polimorfismo Conformacional de Fita Simples (SSCP) e sequenciamento. Foram estudados 24 pacientes com diagnóstico clínico de OI do Hospital Infantil Nossa Senhora da Glória de Vitória, Brasil. As idades dos pacientes variaram de 2 a 16 anos (mediana: 14,5 anos) sendo 15 indivíduos do sexo masculino e 9 do sexo feminino, 11 pacientes apresentam a forma leve da doença, 5 a forma moderada e 9 a forma grave da doença. Os casos letais de OI não foram obtidos por dificuldades metodológicas. Foi encontrado o polimorfismos c.534C>T no exon 2 do gene CRTAP, previamente relatado na literatura, em pacientes da amostra. Não foram identificadas mutações patogênicas neste estudo. Os resultados desse trabalho sugerem que mutações no gene CRTAP são raras na população com OI do ES, corroborando dados da literatura. Esses dados poderão auxiliar na elaboração de estratégias metodológicas mais eficientes para o diagnóstico molecular de OI

RESULTADOS: Participaram do estudo 63 indivíduos (42,9% OI tipo I; 17,5 OI tipo III; 39,7 OI tipo IV). As características clínicas dos indivíduos estavam de acordo com a variabilidade fenotípica da doença. Todos os indivíduos com OI tipo III possuiam baixa estatura grave. Em relação estado nutricional, a maioria dos indivíduos foram classificados como eutróficos, entretanto somando sobrepeso e obesidade foi observado 37,0%, 44,6% e 32,0% para OI tipo I, III e IV, respectivamente. Os resultados das avaliações das dobras cutâneas mostraram-se concordantes à classificação do estado nutricional dos indivíduos, pois pacientes com dobras cutâneas classificadas acima do percentil 85 apresentaram estado nutricional de sobrepeso e obesidade. A gordura corporal calculada através do DEXA apresentou forte correlação (r=0, 803) com a gordura corporal calculada pelo somatório das dobras cutâneas. Em relação ao consumo alimentar a média do percentual de adequação de calorias apresentou diferença significativa entre os dois métodos (OMS ou Kcal/cm) (p=0, 002). Consumo de energia acima de 110% foi observado em 45,6% e 40,4% dos indivíduos para ambos os métodos. A OI tipo III apresentou uma média do percentual de adequação de calorias mais elevado que a OI tipo I e IV em ambos os métodos. Para a classificação da adequação do consumo alimentar de macronutrientes, 12,7% dos indivíduos apresentaram consumo abaixo do ponto de corte mínimo estabelecido para carboidrato, enquanto que 23,8% e 30,8% dos indivíduos apresentaram consumo alimentar acima do ponto de corte máximo para proteína e lipídio, respectivamente. Observamos uma associação entre o diagnóstico nutricional e os pontos de corte de consumo alimentar estabelecidos. A classificação consumo alimentar de cálcio abaixo do ponto de corte mínimo foi observado em 76,2% dos indivíduos, sendo 79,5% a média do percentual de adequação do consumo de cálcio, estando abaixo do ponto de corte mínimo. A média do consumo de cálcio ingerido foi de 770mg/dia. Foi observada uma correlação inversa (r= -0 527) entre a idade e a adequação no consumo de cálcio. CONCLUSÃO: Este estudo demonstra que a OI apresentam uma variabilidade clínica grande. A baixa estatura é uma característica marcante na OI, principalmente, em indivíduos com tipo III. Os indivíduos, em sua maioria, foram classificados como eutróficos, porém foi observada incidência de sobrepeso e obesidade nos pacientes. As dobras cutâneas mostraram- se concordantes com o diagnóstico nutricional dos indivíduos. O percentual de gordura corporal calculada pelo somatório das dobras cutâneas apresentou forte correlação com a percentual de gordura corporal calculado pelo DEXA. Em relação, ao consumo alimentar, indivíduos classificados com OI tipo III, apresentaram maior consumo de energia, do que os indivíduos com OI tipos I e IV. Para o consumo de macronutrientes, embora a maioria dos indivíduos apresentarem consumo adequado, alguns indivíduos apresentaram baixo consumo de carboidrato e alto consumo de proteína e lipídio. O baixo consumo de cálcio apresentou- se 76,2% da população estando abaixo do ponto de corte mínimo. Foi observada também uma correlação inversa entre idade e adequação no consumo de cálcio. Este estudo manifesta a necessidade de uma intervenção nutricional direcionada a estes pacientes uma vez que a adequação do estado nutricional e do consumo alimentar são fatores importantes para a saúde óssea. / BACKGROUND: Osteogenesis Imperfecta (OI) is an inherited disease that results in decreased bone mass and fragility leading to an increased susceptibility to fractures. OBJECTIVE: The aim of this study was to evaluate clinical, anthropometric, nutritional status and describe the profile of food intake in pediatric patients with OI. METHODS: We conducted a cross-sectional study of pediatric patients form 0-19 years of age of both gender attending the OI outpatient clinic of Hospital de Clínicas de Porto Alegre. All subjects underwent clinical evaluation, anthropometric measurements and nutritional assessment. Percentage of body fat was calculated using the sum of skinfolds (triceps and subscapular) and measured by Dual Energy X-Ray Absoptiometry (DEXA). Both measurements were correlated. Food intake was calculated using the food diary for three days and for calculation of calories two methods were used: reference table by age by WHO and the formula Kcal / cm. The values used to ensure adequate intake of macronutrients (carbohydrate, protein and lipid) were according to FAO/ WHO and the food intake of micronutrients (calcium) according to DRI, considering the Adequate Intake (AI) for age. It was established as suitable for food intake of calories and nutrients intake between the cutoffs of 90 to 110%. For data analysis SPSS V.18 was used. The tests for statistical analysis were One Way ANOVA, t-student, Kappa, Pearson correlation tests. We considered significant values p <0.05. RESULTS: The study enrolled 63 subjects (42.9% OI type I, 17.5% OI type III, 39.7% OI type IV). The clinical characteristics of individuals were in agreement with the phenotypic variability of the disease. All individuals with OI type III had been classified with severe short stature. The nutritional status of most individuals were classified as normal, however overweight or obesity were observed respectively in 37.0%, 44.6% and 32.0% for OI type I, III and IV, respectively. The results of evaluations of skinfolds were shown to be consistent with the classification of nutritional status of individuals, because patients with skinfolds above the 85th centile showed nutritional status of overweight and obesity. Body fat estimated by DEXA showed a strong correlation (r = 0.803) with body fat calculated from the sum of skinfolds. Regarding the profile of food consumption the average proportion of adequate calories showed significant difference between the two methods (WHO or Kcal/cm) (p = 0.002). Food consumption in excess of 110% was observed in 45.6% and 40.4% of subjects for both methods. The OI type III showed an average proportion of adequate calories higher than OI type I and IV in both methods. To classify the adequacy of dietary intake of macronutrients 12.7% of subjects had intake below the threshold cutoff for carbohydrate, whereas 23.8 and 30.8% of subjects had food intake above the cutoff limit for protein and lipid. We observed an association between nutritional status and the cutoff of food consumption set. Classification dietary intake of calcium below the minimum cutoff point was observed in 76.2% of subjects and the average intake of calcium was 770mg/dia. We observed an inverse correlation (r = -0.527) between age and calcium intake. CONCLUSION: This study demonstrates that the OI have a great clinical variability. Short stature is a hallmark in OI, especially in individuals with type III. Individuals, in most cases, were classified as normal, but it was found that the incidence of overweight and obesity in patients. The skinfolds were shown to be consistent with the diagnosis of nutritional subjects. skinfolds showed a strong correlation with body fat percentage calculated by DEXA. In relation to the food intake, individuals classified as OI type III, had higher energy consumption than individuals with OI type I and IV. For the consumption of macronutrients, although most people develop adequate intake, some individuals had low carbohydrate intake and high intake of protein and lipid. The low intake of calcium was 76.2% of the population being below the minimum cutoff. There was also an inverse correlation between age and fitness for consumption of calcium. This study shows the need for a nutritional intervention targeted to these patients since their nutritional status and dietary intake are important factors for bone health.

L’ostéogénèse imparfaite(OI) est une maladie génétique rare qui se caractérise, entre autres, par une fragilité accrue des os. Des analyses du génome des patients atteints ont permis d’identifier les mutations qui déclenchaient ce principal symptôme. Pour le tissu osseux, la difficulté dans la compréhension de cette pathologie réside dans la structure multi-échelle du tissu osseux et dans son caractère de tissu vivant renouvelé par le remodelage osseux.Dans cette thèse, nous avons donc dans un premier temps étudié l’impact des différentes mutations sur la structure nanoscopique du tissu osseux de patients OI. Pour ce faire, une technique d’exploration des propriétés physico-chimiques a été développée. Plus particulièrement, nous avons pu mesurer l’apport de la spectroscopie Raman à l’étude du tissu osseux. Cela a permis d’identifier différentes conséquences sur le tissu osseux créées par des mutations touchant des protéines impliquées dans le métabolisme osseux. Ainsi, du point de vue de la spectroscopie Raman, trois groupes de mutations sont dissociables :• les mutations touchant directement le collagène et ses modifications (OI type génétique III, VII et VIII),• les mutations causant l’OI de type VI qui se caractérise par une hyper minéralisation due à une sous production de collagène,• les mutations causant l’OI de type XI qui se caractérise par un taux de substitution en carbonate plus important que la moyenne traduisant un taux de remodelage plus faible.Dans un second temps, l’aspect vivant du tissu osseux a été étudié avec l’étude de la phase de résorption du remodelage osseux. Il a ainsi été montré que les cellules osseuses qui résorbaient la matrice osseuse n’agissaient pas de manière aléatoire, mais qu’elles ciblaient les zones aux propriétés mécaniques et minérales les plus faibles. Ce comportement étudié d’abord sur du tissu osseux adulte sain a été aussi observé sur les os des patients souffrant d’OI. La pathologie n’a pas modifié qualitativement ce comportement. / Osteogenesis imperfecta (OI) is a rare genetic disease, whose main feature is more brittle bone. Genetic analysis identified mutations making the bone more prone to fracture. As the bone is a multistructrural material, while also being a living tissue, the symptoms and consequences of the disease are numerous. During this thesis, the focus was made on a first approach on the differences of nanostructures between the various mutations causing OI. More specifically, a new use of Raman spectroscopy was made in order to study the collagenic matrix as well as the mineral component. It was found that mutations could be gathered in three groups:• Mutations implied directly in the collagen synthesis and in its early modification (OI genetical type III, VII et VIII),• Mutations implied directly in the mineralization of the collagenic matrix, with an hypermineralization of this matrix (OI genetical type VII),• Mutations causing OI genetical type XI, characterized by a high rate of carbonate substitution, implying a low remodeling rate.On the other hand, the living aspect of bone tissue was studied, with a focus made on the resorption phase of the remodeling cycle. It was found on healthy adults bone that the cells were not behaving randomly, but target osteons with lower mechanical and mineral properties. Moreover, the behavior of those cells is not altered by OI: it was found that the cells had the same not-random behavior on bone of OI patients.

RESULTADOS: Participaram do estudo 63 indivíduos (42,9% OI tipo I; 17,5 OI tipo III; 39,7 OI tipo IV). As características clínicas dos indivíduos estavam de acordo com a variabilidade fenotípica da doença. Todos os indivíduos com OI tipo III possuiam baixa estatura grave. Em relação estado nutricional, a maioria dos indivíduos foram classificados como eutróficos, entretanto somando sobrepeso e obesidade foi observado 37,0%, 44,6% e 32,0% para OI tipo I, III e IV, respectivamente. Os resultados das avaliações das dobras cutâneas mostraram-se concordantes à classificação do estado nutricional dos indivíduos, pois pacientes com dobras cutâneas classificadas acima do percentil 85 apresentaram estado nutricional de sobrepeso e obesidade. A gordura corporal calculada através do DEXA apresentou forte correlação (r=0, 803) com a gordura corporal calculada pelo somatório das dobras cutâneas. Em relação ao consumo alimentar a média do percentual de adequação de calorias apresentou diferença significativa entre os dois métodos (OMS ou Kcal/cm) (p=0, 002). Consumo de energia acima de 110% foi observado em 45,6% e 40,4% dos indivíduos para ambos os métodos. A OI tipo III apresentou uma média do percentual de adequação de calorias mais elevado que a OI tipo I e IV em ambos os métodos. Para a classificação da adequação do consumo alimentar de macronutrientes, 12,7% dos indivíduos apresentaram consumo abaixo do ponto de corte mínimo estabelecido para carboidrato, enquanto que 23,8% e 30,8% dos indivíduos apresentaram consumo alimentar acima do ponto de corte máximo para proteína e lipídio, respectivamente. Observamos uma associação entre o diagnóstico nutricional e os pontos de corte de consumo alimentar estabelecidos. A classificação consumo alimentar de cálcio abaixo do ponto de corte mínimo foi observado em 76,2% dos indivíduos, sendo 79,5% a média do percentual de adequação do consumo de cálcio, estando abaixo do ponto de corte mínimo. A média do consumo de cálcio ingerido foi de 770mg/dia. Foi observada uma correlação inversa (r= -0 527) entre a idade e a adequação no consumo de cálcio. CONCLUSÃO: Este estudo demonstra que a OI apresentam uma variabilidade clínica grande. A baixa estatura é uma característica marcante na OI, principalmente, em indivíduos com tipo III. Os indivíduos, em sua maioria, foram classificados como eutróficos, porém foi observada incidência de sobrepeso e obesidade nos pacientes. As dobras cutâneas mostraram- se concordantes com o diagnóstico nutricional dos indivíduos. O percentual de gordura corporal calculada pelo somatório das dobras cutâneas apresentou forte correlação com a percentual de gordura corporal calculado pelo DEXA. Em relação, ao consumo alimentar, indivíduos classificados com OI tipo III, apresentaram maior consumo de energia, do que os indivíduos com OI tipos I e IV. Para o consumo de macronutrientes, embora a maioria dos indivíduos apresentarem consumo adequado, alguns indivíduos apresentaram baixo consumo de carboidrato e alto consumo de proteína e lipídio. O baixo consumo de cálcio apresentou- se 76,2% da população estando abaixo do ponto de corte mínimo. Foi observada também uma correlação inversa entre idade e adequação no consumo de cálcio. Este estudo manifesta a necessidade de uma intervenção nutricional direcionada a estes pacientes uma vez que a adequação do estado nutricional e do consumo alimentar são fatores importantes para a saúde óssea. / BACKGROUND: Osteogenesis Imperfecta (OI) is an inherited disease that results in decreased bone mass and fragility leading to an increased susceptibility to fractures. OBJECTIVE: The aim of this study was to evaluate clinical, anthropometric, nutritional status and describe the profile of food intake in pediatric patients with OI. METHODS: We conducted a cross-sectional study of pediatric patients form 0-19 years of age of both gender attending the OI outpatient clinic of Hospital de Clínicas de Porto Alegre. All subjects underwent clinical evaluation, anthropometric measurements and nutritional assessment. Percentage of body fat was calculated using the sum of skinfolds (triceps and subscapular) and measured by Dual Energy X-Ray Absoptiometry (DEXA). Both measurements were correlated. Food intake was calculated using the food diary for three days and for calculation of calories two methods were used: reference table by age by WHO and the formula Kcal / cm. The values used to ensure adequate intake of macronutrients (carbohydrate, protein and lipid) were according to FAO/ WHO and the food intake of micronutrients (calcium) according to DRI, considering the Adequate Intake (AI) for age. It was established as suitable for food intake of calories and nutrients intake between the cutoffs of 90 to 110%. For data analysis SPSS V.18 was used. The tests for statistical analysis were One Way ANOVA, t-student, Kappa, Pearson correlation tests. We considered significant values p <0.05. RESULTS: The study enrolled 63 subjects (42.9% OI type I, 17.5% OI type III, 39.7% OI type IV). The clinical characteristics of individuals were in agreement with the phenotypic variability of the disease. All individuals with OI type III had been classified with severe short stature. The nutritional status of most individuals were classified as normal, however overweight or obesity were observed respectively in 37.0%, 44.6% and 32.0% for OI type I, III and IV, respectively. The results of evaluations of skinfolds were shown to be consistent with the classification of nutritional status of individuals, because patients with skinfolds above the 85th centile showed nutritional status of overweight and obesity. Body fat estimated by DEXA showed a strong correlation (r = 0.803) with body fat calculated from the sum of skinfolds. Regarding the profile of food consumption the average proportion of adequate calories showed significant difference between the two methods (WHO or Kcal/cm) (p = 0.002). Food consumption in excess of 110% was observed in 45.6% and 40.4% of subjects for both methods. The OI type III showed an average proportion of adequate calories higher than OI type I and IV in both methods. To classify the adequacy of dietary intake of macronutrients 12.7% of subjects had intake below the threshold cutoff for carbohydrate, whereas 23.8 and 30.8% of subjects had food intake above the cutoff limit for protein and lipid. We observed an association between nutritional status and the cutoff of food consumption set. Classification dietary intake of calcium below the minimum cutoff point was observed in 76.2% of subjects and the average intake of calcium was 770mg/dia. We observed an inverse correlation (r = -0.527) between age and calcium intake. CONCLUSION: This study demonstrates that the OI have a great clinical variability. Short stature is a hallmark in OI, especially in individuals with type III. Individuals, in most cases, were classified as normal, but it was found that the incidence of overweight and obesity in patients. The skinfolds were shown to be consistent with the diagnosis of nutritional subjects. skinfolds showed a strong correlation with body fat percentage calculated by DEXA. In relation to the food intake, individuals classified as OI type III, had higher energy consumption than individuals with OI type I and IV. For the consumption of macronutrients, although most people develop adequate intake, some individuals had low carbohydrate intake and high intake of protein and lipid. The low intake of calcium was 76.2% of the population being below the minimum cutoff. There was also an inverse correlation between age and fitness for consumption of calcium. This study shows the need for a nutritional intervention targeted to these patients since their nutritional status and dietary intake are important factors for bone health.

Orientadores: Lília Freire Rodrigues de Souza Li, Carlos Eduardo Steiner / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências / Made available in DSpace on 2018-08-21T05:55:45Z (GMT). No. of bitstreams: 1 Pedroni_MarcusViniciusCosta_M.pdf: 5336681 bytes, checksum: 022385349dc7fcf62951d9f8c466360f (MD5) Previous issue date: 2012 / Resumo: A Osteogênese Imperfeita (OI) é um distúrbio genético caracterizado por baixa massa e fragilidade óssea, e outras manifestações do tecido conjuntivo, decorrente de defeitos qualitativos ou quantitativos do colágeno tipo I. Está associada a mutações nos genes COL1A1 e COL1A2 que codificam respectivamente as cadeias pro'alfa'1-(I) e pro'alfa'-2(I) formadoras da molécula do colágeno tipo I, e mais raramente mutações nos genes reguladores. A OI manifesta-se através de diferentes fenótipos (I-IV), segundo a classificação de Sillence et al. O objetivo deste trabalho foi a análise molecular dos genes COL1A1 e COL1A2 em famílias brasileiras portadoras de OI, em suas diferentes formas clínicas. Fizemos biópsia da pele de 12 famílias com OI para cultura primária dos fibroblastos. Desta cultura extraímos RNA total, que foi usado como molde para transcrição reversa e reação em cadeia de polimerase (PCR) dos genes e sequenciamento automático direto de cDNA. A expressão gênica foi determinada por Real Time PCR e o padrão e grau de expressão das proteínas do colágeno foram analisados por Imunocitoquímica e Western blot. Identificamos nove mutações missense em heterozigose em nove famílias, e duas mutações com alteração na matriz de leitura em famílias com fenótipos dos tipos I, III ou IV de OI. No gene COL1A1 encontramos quatro mutações já descritas: c.613G>A (p.P205A); c.769G> A (p.G257R); c.859G>A (p.G287S); c.1678G>A (p.G560R). No gene COL1A2 encontramos uma mutação já descrita: c.2314G> A (p.G772S) e quatro novas mutações: c.214G>A (p.G72S); c.775G>A (p.G259S); c.793G> C (p.G265R) e c.3467G>A (p.R1156K). Encontramos hiperexpressão dos transcritos de COL1A1 e COL1A2, porém expressão normal das cadeias 'alfa'1 e 'alfa'2 da proteína do colágeno em todos os pacientes. As cadeias mutada apresentaram padrão desorganizado nas células. Pacientes com OI apresentaram hiperexpressão dos genes de colágeno tipo I sugerindo que estes genes são regulados e que as meia vidas destas proteínas estão reduzidas / Abstract: Osteogenesis Imperfecta (OI) is a genetic disorder characterized by low bone mass and bone fragility, and other manifestations of connective tissue, due to qualitative or quantitative defects of type I collagen. It is associated with mutations in COL1A1 and COL1A2 genes, that encode respectively the pro'alpha'-1(I) and pro'alpha'-2(I) chains, forming the molecule of type I collagen, and more rarely mutations in regulatory genes. The OI is manifested by various phenotypes (I-IV), according to the classification of Sillence et al. The objective of this study was the molecular analysis of COL1A1 and COL1A2 genes in Brazilian families with OI, in its different clinical forms. We performed skin biopsy from 12 families with OI for primary culture of fibroblasts. From this culture, we made total RNA extract, which was used as template for reverse transcription and polymerase chain reaction (PCR), and automated sequencing directly from cDNA. Gene expression was determined by Real Time qPCR and the level of expression of collagen proteins were analyzed by immunocytochemistry and Western Blot. We identified heterozygous mutations in 11 families that have phenotypes of types I, III or IV of OI. In the COL1A1 gene found four previously described mutations: c.613G> A (p.P205A), c.769G> A (p.G257R), c.859G> A (p.G287S), c.1678G> A (p. G560R). In the COL1A2 gene we found one previously described mutation: c.2314G> A (p.G772S) and four new mutations: c.214G> A (p.G72S), c.775G> A (p.G259S), c.793G> C (p.G265R) and c.3467G> A (p.R1156K). We found upregulation of the transcripts of COL1A1 and COL1A2 genes, but a normal expression of 'alpha'1 and 'alpha'2 protein chains in all patients. The mutant chain showed disorganized on the immunocytochemestry. Patients with OI showed upregulation of type I collagen genes, suggesting regulation and decreasing half lives of the proteins / Mestrado / Saude da Criança e do Adolescente / Mestre em Ciências

Les Amélogenèses imparfaites constituent un groupe d’altération de l’émail dentaire d’origine génétique. Cette pathologie peut exister de manière isolée ou associée à d’autres symptômes dans le cadre de syndromes. Certains gènes impliqués sont déjà connus, cependant de nouvelles mutations et de nouveaux gènes restent à identifier. L’étude de familles informatives dans le cadre de ce projet de recherche sur le massif crânio-facial et bucco-dentaire, associée à des stratégies d’identification génétique telles que la sélection de gènes candidats, les zones d’homozygotie, le séquençage haut débit, ont permis d’obtenir des résultats probants. Des investigations futures passant par l’augmentation des cohortes, le développement des outils de séquençage de nouvelle génération, l’étude des modèles cellulaires et animaux permettront d'améliorer la compréhension de l’amélogenèse. / Amelogenesis imperfecta (AI) represents hereditary conditions affecting the quality and quantity of enamel. This disease can exist in isolation or in association with other symptoms in the form of syndromes. Several genes involved in AI are already known, however mutations in these genes are not sufficient to explain all cases of AI. This suggests that mutations in yet unidentified genes underlie AI. The study of informative families included in this research project on cranio-facial and oro-dental anomalies, by using genetic strategies such as candidate gene mutational analysis,homozygosity mapping and next generation sequencing, allowed the discovery of novel genes and mutations in AI. Future investigations based on the recruitment of new families, the development of new next generation sequencing tools and the establishment of cellular and animal models will improve our understanding of amelogenesis.

Osteogenesis imperfecta is an inherited disorder caused mainly by collagen type I genes mutations, COL1A1 and COL1A2. These mutations affect especially connective tissue. Disease is characterized by fragile bones, deformations and increased frequency of fractures. It's worldwide extensive disorder regardless of age, sex, nationality or races. The incidence is 1: 16 - 20 000 births. Currently, we described nine clinically distinct forms of Osteogenesis imperfecta. Only the first four types OI, type I-IV, are caused by collagen type I genes mutations . In these nine types there are distinguished mild and severe forms. Type II and III are lethal forms, death occur offen during prenatal period or in the first days of the life affected individuals. Characteristic clinical features of collagen forms OI are an increased incidence of fractures, deformations of bones, blue sclera, hearing loss, Dentinogenesis imperfecta small or subnormal growth (Marini, 2010). This study alignment is mainly the description of the clinical forms, exploring the molecular basis of disease and determine the relationship between the type and position of the mutation and the resulting phenotype of affected individuals. We have analysed exons 31-40, including associated non-coding regions, of the COL1A1 gene (so-called MLBR =...

The present study evaluates two fetal individuals (B532 and B625) from the Kellis 2 cemetery (Roman period circa A.D. 50 A.D. 450), Dakhleh Oasis, Egypt, that display skeletal anomalies that may explain their death. Both individuals exhibit bowing of the long bones in addition to other skeletal deformities unique to each individual. To assess these pathologies a differential diagnosis based on the congenital occurrence of long bone bowing is developed. Long bone bowing is selected because it is the more prevalent abnormality in the paleopathological literature and the other abnormalities are not as easily identifiable in the literature. For the purposes of this study, the differential diagnosis is defined as a process of comparing the characteristics of known diseases with those shared by an archaeological specimen, in the anticipation of diagnosing the possible condition. It is expected that the differential diagnosis will assist in providing a thorough assessment of each skeleton and yield a possible diagnosis for the condition(s). Macroscopic and radiographic analyses are used to document and examine the bone abnormalities for each individual and compare the results with the developed differential diagnosis. Results suggest that the bent long bones of B532 were caused by osteogenesis imperfecta whereas the cause of the bent long bones of B625 is not clear. Further analyses of B625, including the pathologic abnormalities of its skull, suggest that the neural tube defect iniencephaly with associated encephalocele was the likely cause of the observed skeletal abnormalities. The abnormalities of the long bones complicate estimations of the age-at-death of these two individuals, thus the pars basilaris bone was used to assess age estimation. A population sample of 37 Kellis 2 fetal individuals allowed for the development of linear regression formulae of the pars basilaris measurements for long bone length estimates and a comparison of which would provide the most accurate age estimate. Finally, the diagnoses of the fetal specimens are considered in relation to the cultural aspects and disease pattern of the Kellis 2 cemetery

Thesis written in co-mentorship with director: Nelly Huynh; co-directors: Frank Rauch and Jean-Marc Retrouvey; collaborators: Clarice Nishio, Duy-Dat Vu and Nathalie Alos / Introduction - L'ostéogenèse imparfaite (OI) est une maladie osseuse héréditaire qui affecte la production du collagène de type I et le remodelage osseux. Les biphosphonates sont administrés aux enfants atteints d'OI dans le but d’augmenter la masse osseuse et de réduire les fractures osseuses. Les patients atteints d’OI ont des malocclusions sévères qui affectent leur qualité de vie. Plusieurs processus biologiques de remodelage osseux qui sont nécessaires pour un mouvement dentaire orthodontique sont affectés chez les gens atteints d’OI. L'objectif de cette étude est d'évaluer le mouvement dentaire orthodontique dans un modèle de souris avec OI et traitées aux biphosphonates. Matériels et méthodes - Vingt-quatre souris femelles âgées de 10 semaines ont été divisés en 4 groupes : 1 - OI traitées par zolédronate (n=6); 2 - OI non traitées (n=6); 3 - Type sauvage traitées par zolédronate (n=6); 4 – Type sauvage non traitées (n=6) Un ressort de nickel-titane activé à 10 g de force a été cimenté entre les incisives et la 1ère molaire maxillaire droite. Le côté contralatéral a été utilisé comme témoin. Une dose de 0,05 mg de zolédronate a été administrée par voie sous-cutanée un jour avant la chirurgie. Sept jours après l'intervention, les souris ont été euthanasiées et la distance entre la 1ère et la 2e molaire a été mesurée par analyse microtomographique. Résultats - Le mouvement dentaire orthodontique était significativement plus important chez les souris OI que celles de types sauvages dans les groupes non traités (p < 0,05). Le traitement par zolédronate n'a eu aucun effet significatif sur le mouvement dentaire orthodontique au sein des groupes OI et type sauvages. Conclusions - Ces résultats suggèrent une augmentation du mouvement dentaire orthodontique chez les souris avec l’ostéogenèse imparfaite. / INTRODUCTION - Osteogenesis imperfecta (OI) is a heritable bone disorder that affects collagen type I production and bone remodeling. Orthodontic tooth movement (OTM) involves the underlying process of alveolar bone remodeling. The objective of this study is to evaluate OTM in a mouse model of OI. METHODS - Twenty four, 10 week-old female mice were divided into 4 groups: 1- OI treated with zoledronate, 2- OI untreated, 3- Wild-type (WT) treated with zoledronate and 4- WT untreated. A nickel-titanium closed coil spring (10 g) was attached between the incisors and the right maxillary 1st molar. The contralateral side was used as control. Zoledronate (0.05mg/kg) was administered sub-cutaneously 1 day prior to surgery. Seven days after the procedure, the distance between 1st – 2nd molars was measured by micro-CT. RESULTS - OI mice presented significantly more OTM than WT mice when comparing within untreated groups (p<0.05). Zoledronate treatment had no significant effect on OTM within OI and WT groups. CONCLUSIONS - These results suggest increased OTM in mice with OI. The dose of zoledronate administrated 1 day prior to surgery had no significant effect on OTM.

A osteogênese imperfeita (OI) é caracterizada como uma desordem genética na qual uma osteopenia generalizada leva a baixa estatura, fragilidade óssea excessiva e deformidades ósseas graves. As células mesenquimais estromais multipotentes (CTMs) são precursores presentes na medula óssea adulta capazes de se diferenciar em osteoblastos, adipócitos e mioblastos que passaram a ter grande importância como fonte terapia celular. O objetivo do presente estudo foi analisar o perfil de expressão gênica durante a diferenciação osteogênica a partir de células mesenquimais estromais multipotentes da medula óssea obtidas de pacientes diagnosticados com Osteogênese Imperfeita e de indivíduos controle. Foram coletadas amostras de três indivíduos normais e cinco amostras de pacientes portadores de Osteogênese Imperfeita. As células mononucleares (CMN) foram isoladas para a obtenção de células mesenquimais que foram expandidas até a terceira passagem quando iniciou-se o estímulo para diferenciação osteogênica. Também foram realizadas análises para contagem de CFU-F e para quatro das cinco amostras de pacientes portadores de OI, o número de CFU-F observado foi inferior ao geralmente encontrado para amostras de doadores normais. Foram coletadas células para análises de imunofenotipagem celular por citometria de fluxo e o RNA foi extraído originando a amostra denominada T0. As garrafas restantes tiveram suas células estimuladas para diferenciação osteogênica. Após um dia em cultura com estímulo, mais uma garrafa teve o RNA de suas células extraído (T1), e o mesmo procedimento foi realizado nos dias 2 (T2), 7 (T7), 12 (T12), 17 (T17) e 21 (T21). Todas as amostras demonstraram possuir potencial de diferenciação in vitro em osteoblastos e adipócitos. A imunofenotipagem de células mesenquimais foi realizada e as amostras de todos os pacientes apresentaram perfil imunofenotípico compatível com trabalhos anteriores. Foram identificadas mutações nos genes COL1A1 e/ou COL1A2 responsáveis pelo desenvolvimento da doença para quatro dos cinco pacientes avaliados. Para o paciente portador de Osteogênese Imperfeita e Síndrome de Bruck a região codificadora do gene PLOD2 também foi seqüenciada, porém não foram encontradas mutações. A análise da expressão gênica foi realizada pela técnica de microarranjos e foram identificados vários genes com expressão diferencial. Alguns genes com importância fundamental na diferenciação osteoblástica apresentaram menor expressão nas amostras dos pacientes portadores de OI, sugerindo um menor comprometimento das CTMs desses pacientes com a linhagem osteogênica. Outros genes também tiveram sua expressão diferencial confirmada por PCR em Tempo Real. Foi observado um aumento na expressão de genes relacionados a adipócitos, sugerindo um aumento da diferenciação adipogênica em detrimento à diferenciação osteogênica. A expressão das variantes do gene PLOD2 mostrou-se diferencial entre amostras normais, de OI e do paciente portador de Síndrome de Bruck. Também foi evidenciada uma expressão diferencial do microRNA 29b, um microRNA com papel estabelecido durante a diferenciação osteogênica, sugerindo um mecanismo de regulação dependente da quantidade de RNAm do seu gene alvo, o COL1A1. / Osteogenesis imperfecta (OI) is characterized as a genetic disorder in which a generalized osteopenia leads to short stature, bone fragility and serious skeletal deformities. Mesenchymal stem cells (MSCs) are precursors present in adult bone marrow that can differentiate into osteoblasts, adipocytes and myoblasts that have been given great importance as a source cell therapy. The aim of this study was to analyze the gene expression profile during osteogenic differentiation from mesenchymal stem cells from bone marrow taken from patients diagnosed with Osteogenesis Imperfecta and control subjects. Samples were collected from three normal individuals and five samples from patients with Osteogenesis Imperfecta. Mononuclear cells (MON) were isolated to obtain mesenchymal cells that were expanded until third passage when the stimulus for osteogenic differentiation was induced. Analyses were also conducted to count the CFU-F and for four of the five samples from patients with OI, the number of CFU-F observed was lower than generally found for normal samples. Cells were collected for analysis of cell immunophenotyping by flow cytometry and RNA was extracted from the resulting sample called T0. Remaining cells were stimulated for osteogenic differentiation. After a day in culture with stimulation, cells from another bottle had their RNA extracted (T1), and the same procedure was performed on days 2 (T2), 7 (T7), 12 (T12), 17 (T17) and 21 (T21). All samples have shown potential of in vitro differentiation into osteoblasts and adipocytes. Immunophenotyping of mesenchymal cells was performed and samples of all patients had immunophenotypic profile consistent with previous works. We identified mutations in COL1A1 and / or COL1A2 responsible for developing the disease for four of five patients. For the patient with Osteogenesis Imperfecta and Bruck Syndrome, coding region of the gene PLOD2 was also sequenced, but no mutations were found. The gene expression analysis was performed by microarray and identified several genes with differential expression. Some genes of fundamental importance in osteoblast differentiation showed lower expression in samples from patients with OI, suggesting a minor involvement of MSCs of patients with osteogenic lineage. Other genes also confirmed their differential expression by Real Time PCR. We observed an increased expression of genes related to adipocytes, suggesting an increased adipogenic differentiation at the expense of osteogenic differentiation. The expression of PLOD2 gene variants proved to be different between normal samples, OI and the patient with Bruck Syndrome. There was also evidence of differential expression of 29b microRNA, with established role during osteogenic differentiation, suggesting a mechanism dependent regulation of mRNA abundance of its gene target, COL1A1.