Structure of the imprinted mouse Snrpn gene and establishment of its parental-specific methylation pattern

The mouse Snrpn gene encodes the Smn protein, which is involved in RNA splicing. The gene maps to a region in the central part of chromosome 7 that is syntenic to the Prader–Willi/Angelman syndromes (PWS-AS) region on human chromosome 15q11-q13. The mouse gene, like its human counterpart, is imprinted and paternally expressed, primarily in brain and heart. We provide here a detailed description of the structural features and differential methylation pattern of the gene. We have identified a maternally methylated region at the 5′ end (DMR1), which correlates inversely with the Snrpn paternal expression. We also describe a region at the 3′ end of the gene (DMR2) that is preferentially methylated on the paternal allele. Analysis of Snrpn mRNA levels in a methylase-deficient mouse embryo revealed that maternal methylation of DMR1 may play a role in silencing the maternal allele. Yet both regions, DMR1 and DMR2, inherit the parental-specific methylation profile from the gametes. This methylation pattern is erased in 12.5-days postcoitum (dpc) primordial germ cells and reestablished during gametogenesis. DMR1 is remethylated during oogenesis, whereas DMR2 is remethylated during spermatogenesis. Once established, these methylation patterns are transmitted to the embryo and maintained, protected from methylation changes during embryogenesis and cell differentiation. Transfections of DMR1 and DMR2 into embryonic stem cells and injection into pronuclei of fertilized eggs reveal that embryonic cells lack the capacity to establish anew the differential methylation pattern of Snrpn. That all PWS patients lack DMR1, together with the overall high resemblance of the mouse gene to the human SNRPN, offers an excellent experimental tool to study the regional control of this imprinted chromosomal domain.

Autoridade parental, incapacidade e melhor interesse da criança : uma reflexão sobre o caso Ashely / Ana Carolina Brochado Teixeira e Luciana Dadalto Penalva. --

Inclui notas explicativas, bibliográficas e bibliografia.

A resource range invariance rule for optimal offspring size predicts patterns of variability in parental phenotypes

Previous analysis of the rules regarding how much more a female should invest in a litter of size C rather than producing a litter with one more offspring revealed an invariance relationship between litter size and the range of resources per offspring in any litter size. The rule is that the range of resources per offspring should be inversely proportional to litter size. Here we present a modification of this rule that relates litter size to the total resources devoted to reproduction at that litter size. The result is that the range of resources devoted to reproduction should be the same for all litter sizes. When parental phenotypes covary linearly with resources devoted to reproduction, then those traits should also show equal ranges within each litter size category (except for litters of one). We tested this prediction by examining the range in body size (=total length) of female mosquito fish (Gambusia hubbsi) at different litter sizes. Because resources devoted to reproduction may take many forms (e.g., nest defense), this prediction may have broad applicability.

Contribution of parental blood pressures to association between low birth weight and adult high blood pressure: cross sectional study

Objective: To examine the possibility that low birth weight is a feature of the inherited predisposition to high blood pressure.

An interspecies hybrid RNA virus is significantly more virulent than either parental virus.

Cucumber mosaic cucumovirus (CMV) infects a very wide range of plant species (>1000 species). We recently demonstrated that a previously undescribed gene (2b) encoded by RNA 2 of the tripartite RNA genome of CMV is required for systemic virus spread and disease induction in its hosts. Herein we report that when this CMV gene is replaced by its homologue from tomato aspermy cucumovirus (TAV), the resultant hybrid virus is significantly more virulent, induces earlier onset of systemic symptoms, and accumulates to a higher level in seven host species from three families than either of the parents. Our results indicate that CMV and the TAV 2b protein interact synergistically despite the fact that no synergism occurs in double infections with the two parental viruses. To our knowledge, this is the first example of an interspecific hybrid made from plant or animal RNA viruses that is more efficient in systemic infection of a number of hosts than the naturally occurring parents. As CMV and the hybrid virus accumulated to a similar level in the infected tobacco protoplasts, the observed synergistic responses most likely resulted from an increased efficacy of the hybrid virus in systemic spread in host plants provided by the TAV 2b protein. The relevance of our finding to the application of pathogen-derived resistance is discussed.

Making and Keeping Friends: A social skills game that promotes parental involvement to more effectively address social deficits in children with ADHD

The social deficits of children with attention-deficit/hyperactivity disorder (ADHD) have great impact on overall functioning and life satisfaction; however, ways of addressing these deficits to promote positive interpersonal functioning have been limited. The following paper explores the literature that highlights these social deficits, identifies skills that are proposed to target these impairments, discusses child and parent factors that are relevant to positive therapeutic change, and describes the development of a therapeutic game that incorporates variables important to treatment success of these interpersonal difficulties.

El estudio de caso como estrategia para el análisis de la violencia filio-parental (VFP)

Las investigaciones sobre la violencia filio-parental (VFP) son escasas y llegan a conclusiones diversas. El estudio de caso como estrategia metodológica puede ser útil para conocer en profundidad un fenómeno del que aún sabemos poco, entendiendo su realidad como proceso y permitiendo su comprensión de forma holística.

Corrélats neuronaux du circuit des récompenses chez les jeunes à risque parental de troubles de l'humeur

Cette thèse a pour objectif l’investigation du circuit des récompenses, sur les plans comportementaux et neuronaux, chez des adolescents à risque parental élevé de dépression majeure et de trouble bipolaire, en comparaison à des jeunes à risque parental peu élevé. Plus précisément, le but est d’identifier des marqueurs comportementaux et neuronaux du risque de développer une dépression majeure ou un trouble bipolaire, afin d’être en mesure de détecter et de prévenir ces troubles le plus tôt possible pour éviter, ou du moins retarder, leur émergence. Pour ce faire, nous avons réalisé deux études, présentées ici dans deux articles empiriques. Dans le premier article, le fonctionnement comportemental et neuronal du circuit des récompenses a été investigué au moyen d’une tâche d’anticipation et d’obtention de gains et de pertes monétaires, chez des adolescents à risque parental de dépression majeure (i.e., jeunes asymptomatiques dont un des parents souffre de dépression majeure), des adolescents à risque parental de trouble bipolaire (i.e., jeunes asymptomatiques dont un des parents souffre de trouble bipolaire) et des adolescents contrôles (i.e., jeunes asymptomatiques dont les deux parents sont en bonne santé mentale). Au niveau comportemental, les résultats ont révélé une meilleure performance chez les jeunes à risque de dépression majeure lorsqu’ils devaient éviter d’obtenir des pertes monétaires de magnitude variée (0,20$, 1$ ou 5$), ainsi qu’une meilleure performance chez les jeunes à risque de trouble bipolaire sur les essais impliquant d’éviter des pertes monétaires de magnitude nulle (0$). Au niveau neuronal, les jeunes à risque de dépression majeure démontraient une diminution de l’activation du cortex préfrontal dorsolatéral lors de l’anticipation de potentielles pertes monétaires de magnitude variée, tandis que les jeunes à risque de trouble bipolaire démontraient une diminution de l’activation du cortex préfrontal dorsolatéral lors de l’anticipation de potentielles pertes monétaires de magnitude nulle. De plus, les jeunes à risque de dépression majeure tendaient à démontrer une augmentation de l’activité du cortex orbitofrontal durant l’évitement réussi de pertes monétaires, tandis que les jeunes à risque de trouble bipolaire tendaient à démontrer une augmentation de l’activité du cortex orbitofrontal lors de l’obtention de pertes monétaires. Dans le deuxième article, l’intégrité structurelle des régions fronto-limbiques a été investiguée, au moyen de mesures du volume, de l’épaisseur corticale et de la superficie corticale. Les résultats ont mis en évidence, chez les jeunes à risque de trouble bipolaire, un volume plus élevé du cortex préfrontal dorsolatéral, par rapport aux jeunes à risque de dépression majeure et contrôles. De plus, les jeunes à risque de trouble bipolaire présentaient un volume plus élevé du cortex cingulaire postérieur, en comparaison aux jeunes à risque de dépression majeure. Enfin, une diminution de l’épaisseur corticale du cortex orbitofrontal et du gyrus frontal moyen a été observée chez les adolescents à risque de trouble bipolaire, en comparaison au groupe contrôle. L’ensemble de ces résultats démontre ainsi l’existence de particularités comportementales et d’altérations neuronales sur les plans fonctionnel et structurel, chez des jeunes à risque élevé de troubles de l’humeur, et ce, avant même l’émergence des premiers symptômes thymiques. Plus particulièrement, ces caractéristiques pourraient constituer des marqueurs du risque de développer un trouble de l’humeur. Par conséquent, ces marqueurs pourraient aider à mieux identifier les jeunes qui sont le plus à risque de développer un trouble de l’humeur, et ainsi permettre la mise en place précoce de stratégies préventives adaptées, afin d’éviter des trajectoires développementales psychopathologiques.

Reciprocal Prospective Associations Between Depressive Symptoms and Perceived Relationship With Parents in Early Adolescence

Objective: Adolescent depressive symptoms are associated with difficult family relationships. Family systems and interpersonal theories of depression suggest that this association could reflect a circular process in which symptoms and family functioning affect each other over time. Few longitudinal studies have tested this hypothesis, and the results of these studies have been equivocal. In this study, we examine reciprocal prospective associations in early adolescence between depressive symptoms and 2 important aspects of parent–child relationships: communication and conflict. Methods: Participants were 3862 students who annually filled out self-reports. Path analysis was used to examine prospective associations between depressive symptoms and perceived communication and conflict with parents from the age of 12 to 13 and 14 to 15 years. Independence of these associations was assessed by controlling for family context (parental separation and family socioeconomic status) and adolescent behaviour problems (delinquent behaviours and substance use). Sex differences were evaluated with multiple group analysis. Results: Reciprocal prospective associations were found between depressive symptoms and perceived conflict with parents, but not between depressive symptoms and communication with parents. Depressive symptoms were found to predict poorer communication with parents over time, but communication was not predictive of lower depressive symptoms in subsequent years. All paths were sex-invariant and independent from family context and behaviour problems. Conclusion: This study highlights the importance of considering the potential impact of adolescent symptomatology on parent–child relationships and suggests that reciprocity may characterize the association between depressive symptoms and negative aspects of parent–child relationships. The role of adolescent perceptions in the interplay between depressive symptoms and family relationships remains to be clarified.

Les variations spatiales du comportement policier: l'exemple de la Sûreté du Québec

Travail dirigé présenté en vue de l’obtention du grade de maîtrise en criminologie option sécurité intérieure

Evolução da perceção parental da imagem corporal da criança : análise retrospetiva de dois estudos

Introdução: A obesidade é reconhecida pela OMS como um importante problema de saúde pública, que afeta adultos, crianças e adolescentes e que tem tomado proporções epidémicas em todo o mundo. Os estudos revelam que os pais, mas sobretudo as mães se mostram preocupadas e concordam com a adoção de hábitos alimentares saudáveis, no entanto a perceção que estas têm do estado nutricional dos filhos nem sempre é adequada e frequentemente a imagem corporal é distorcida, percebendo-se contudo que esta distorção tem vindo a diminuir. Foi neste âmbito que emergiu como objetivo geral deste estudo, explorar a evolução da perceção parental da imagem corporal da criança em dois estudos, estudo A (Graça Aparício) e estudo B (Graça Aparício, Madalena Cunha, João Duarte; Anabela Pereira, Jorge Bonito, Carlos Albuquerque), publicados respetivamente, em 2012 e 2013 e relacioná-la com o comportamento alimentar da criança do estudo B. Material e métodos: Este estudo de carácter retrospetivo e transversal, foi realizado com as crianças que participaram no estudo A e no estudo B, num total de 2216 crianças em idade pré-escolar, média idade= 4.51 anos (±0.97Dp), residentes as crianças do estudo A na região de Viseu e Dão e as do estudo B, nas regiões Viseu, Lamego, Vila Real, Évora e Leiria, tendo sido efetuada pelos autores originais, uma avaliação antropométrica e classificação nutricional das crianças com base no referencial NCHS (CDC, 2000). Para a recolha de dados os autores originais, utilizaram um Questionário de Caracterização Sociodemográfica das Crianças e dos Progenitores; o Questionário de Avaliação da Perceção Parental da Imagem Corporal da criança (Collins, 1991) e o Questionário de Caracterização do Comportamento Alimentar Infantil (CEBQ), traduzido e validado para a população portuguesa por Viana & Sinde (2008). Resultados: Comparativamente ao estudo A, no estudo B os pais revelaram-se significativamente mais preocupados com o estado nutricional dos seus filhos (p= 0,000). Ainda no estudo B uma maior percentagem de pais assinala as imagens representativas de pré-obesidade (27,5%) e obesidade (0,6%), comparativamente ao estudo A, onde se verifica o oposto; uma maior sinalização das crianças no grupo da normalidade e baixo-peso (56,3% e 20,4% respetivamente). Apurou-se uma diferença de médias significativa da perceção parental da imagem corporal da criança entre o estudo A e o estudo B, evidenciando a perceção dos pais, a uma maior aproximação com os valores mais elevados de IMC dos filhos, ou seja, os pais têm uma perceção menos distorcida da imagem corporal dos filhos, quando estes apresentam valores de IMC mais elevados. Relativamente ao comportamento alimentar, apesar dos comportamentos de “atração pela comida” se associarem a uma perceção parental de imagem corporal maior, e de alguns dos comportamentos de “evitamento da comida” se associarem a uma perceção parental de imagem corporal menor, a relação entre o comportamento alimentar e a perceção parental da imagem corporal criança não se revelou significativa. Conclusões: Os resultados indicam uma maior acurácia da perceção da imagem corporal dos pais ao real estado nutricional dos filhos, podendo este facto ser o primeiro passo para o seu reconhecimento do excesso de peso dos seus filhos e facilitar a adequação a um estilo de vida mais saudável entre as crianças em idade pré-escolar, e maior sensibilização da família para o controlo do excesso de peso na infância. Palavras-chave: Perceção parental, imagem corporal, Obesidade infantil.