42 research outputs found

    The neurogenic effects of exogenous neuropeptide Y: early molecular events and long-lasting effects in the hippocampus of trimethyltin-treated rats.

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    Modulation of endogenous neurogenesis is regarded as a promising challenge in neuroprotection. In the rat model of hippocampal neurodegeneration obtained by Trimethyltin (TMT) administration (8 mg/kg), characterised by selective pyramidal cell loss, enhanced neurogenesis, seizures and cognitive impairment, we previously demonstrated a proliferative role of exogenous neuropeptide Y (NPY), on dentate progenitors in the early phases of neurodegeneration. To investigate the functional integration of newly-born neurons, here we studied in adult rats the long-term effects of intracerebroventricular administration of NPY (2 \ub5g/2 \ub5l, 4 days after TMT-treatment), which plays an adjuvant role in neurodegeneration and epilepsy. Our results indicate that 30 days after NPY administration the number of new neurons was still higher in TMT+NPY-treated rats than in control+saline group. As a functional correlate of the integration of new neurons into the hippocampal network, long-term potentiation recorded in Dentate Gyrus (DG) in the absence of GABAA receptor blockade was higher in the TMT+NPY-treated group than in all other groups. Furthermore, qPCR analysis of Kruppel-like factor 9, a transcription factor essential for late-phase maturation of neurons in the DG, and of the cyclin-dependent kinase 5, critically involved in the maturation and dendrite extension of newly-born neurons, revealed a significant up-regulation of both genes in TMT+NPY-treated rats compared with all other groups. To explore the early molecular events activated by NPY administration, the Sonic Hedgehog (Shh) signalling pathway, which participates in the maintenance of the neurogenic hippocampal niche, was evaluated by qPCR 1, 3 and 5 days after NPY-treatment. An early significant up-regulation of Shh expression was detected in TMT+NPY-treated rats compared with all other groups, associated with a modulation of downstream genes. Our data indicate that the neurogenic effect of NPY administration during TMT-induced neurodegeneration involves early Shh pathway activation and results in a functional integration of newly-generated neurons into the local circuit

    Migration-related detention centers : The challenges of an ecological perspective with a focus on justice

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    Background: In recent years, border control and migration-related detention have become increasingly widespread practices affecting the lives of undocumented migrants, their families, and communities at large. In spite of the concern within academia, few studies have directly witnessed the life and experiences of people confined to migration-related detention centers. In the medical and psychological fields, a considerable body of research has demonstrated the pathogenic nature of detention in terms of mental health, showing an association between length of detention and severity of distress. Nevertheless, it was limited to the assessment of individuals’ clinical consequences, mainly focusing on asylum seekers. There currently exists a need to adopt an ecological perspective from which to study detained migrants’ experiences as context-dependent, and influenced by power inequalities. This paper addresses this gap. Discussion: Drawing upon advances in community psychology, we illustrate an ecological framework for the study of migration-related detention contexts, and their effects on the lives of detained migrants and all people exposed to them. Making use of existing literature, Kelly’s four principles (interdependence, cycling of resources, adaptation, succession) are analyzed at multiple ecological levels (personal, interpersonal, organizational, communal), highlighting implications for future research in this field. A focus on justice, as a key-dimension of analysis, is also discussed. Wellbeing is acknowledged as a multilevel, dynamic, and value-dependent phenomenon. Summary: In presenting this alternative framework, the potential for studying migration-related detention through an ecological lens is highlighted, pointing the way for future fields of study. We argue that ecological multilevel analyses, conceptualized in terms of interdependent systems and with a focus on justice, can enhance the comprehension of the dynamics at play in migration-related detention centers, providing an effective tool to address the multi-level challenges of doing research within them. Furthermore, they can contribute to the development of policies and practices concerned with health, equality, and human rights of all people exposed to migration-related detention. Consistent with these assumptions, empirical studies adopting such a framework are strongly encouraged. These studies should use mixed and multi-method culturally situated designs, based on the development of collaborative and empowering relationships with participants. Ethnographic approaches are recommended.Fundação para a Ciência e Tecnologia (FCT

    Is theory of mind related to social dysfunction and emotional problems in 22q11.2 deletion syndrome (velo-cardio-facial syndrome)?

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    Social dysfunction is intrinsically involved in severe psychiatric disorders such as depression and psychosis and linked with poor theory of mind. Children with 22q11.2 deletion syndrome (22q11DS, or velo-cardio-facial syndrome) have poor social competence and are also at a particularly high risk of developing mood (40%) and psychotic (up to 30%) disorders in adolescence and young adulthood. However, it is unknown if these problems are associated with theory of mind skills, including underlying social-cognitive and social-perceptual mechanisms. The present cross-sectional study included classic social-cognitive false-belief and mentalising tasks and social-perceptual face processing tasks. The performance of 50 children with 22q11DS was compared with 31 age-matched typically developing sibling controls. Key findings indicated that, while younger children with 22q11DS showed impaired acquisition of social-cognitive skills, older children with 22q11DS were not significantly impaired compared with sibling controls. However, children with 22q11DS were found to have social-perceptual deficits, as demonstrated by difficulties in matching faces on the basis of identity, emotion, facial speech and gaze compared with sibling controls. Furthermore, performance on the tasks was associated with age, language ability and parentally rated social competence and emotional problems. These results are discussed in relation to the importance of a better delineation of social competence in this population
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