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51.

Medically unexplained physical symptoms are frequently named by adolescents in both clinical and normative samples. This study analyzed the associations between parental rearing styles and adolescents’ body complaints in diverse cultural contexts. In a cross-cultural study of 2415 adolescents from eight countries (Argentina, France, Germany, Greece, Pakistan, Peru, Poland, and Turkey), the associations of maternal and paternal support, psychological control, and an anxious parental monitoring style with youth body complaints were tested. Girls reported more somatic complaints than boys, the level of complaints differed between countries, and gender differences varied significantly between countries. Hierarchic multilevel models revealed that the expression of distress via body complaints, after controlling for country, gender, and sociodemographic status, was significantly associated with parental rearing styles. The negative impact of mothers’ psychological control on body complaints generalize across countries. In addition, mothers’ anxious monitoring had a negative impact on the offspring’s health, whereas higher levels of paternal support and lower levels of paternal psychological control contributed to lower levels of somatic complaints. Sociodemographic variables such as family structure, standard of living, and employment status of the parents, did not turn out as significant in the final model. The findings point to the different roles of fathers and mothers play in adolescents’ health and their complex interplay.

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Oligodendrocyte progenitor cells (OPCs) are specified from discrete precursor populations during gliogenesis and migrate extensively from their origins, ultimately distributing throughout the brain and spinal cord during early development. Subsequently, a subset of OPCs differentiates into mature oligodendrocytes, which myelinate axons. This process is necessary for efficient neuronal signaling and organism survival. Previous studies have identified several factors that influence OPC development, including excitatory glutamatergic synapses that form between neurons and OPCs during myelination. However, little is known about how glutamate signaling affects OPC migration before myelination. In this study, we use in vivo, time-lapse imaging in zebrafish in conjunction with genetic and pharmacological perturbation to investigate OPC migration and myelination when the GluR4A ionotropic glutamate receptor subunit is disrupted. In our studies, we observed that gria4a mutant embryos and larvae displayed abnormal OPC migration and altered dorsoventral distribution in the spinal cord. Genetic mosaic analysis confirmed that these effects were cell-autonomous, and we identified that voltage-gated calcium channels were downstream of glutamate receptor signaling in OPCs and could rescue the migration and myelination defects we observed when glutamate signaling was perturbed. These results offer new insights into the complex system of neuron-OPC interactions and reveal a cell-autonomous role for glutamatergic signaling in OPCs during neural development.SIGNIFICANCE STATEMENT The migration of oligodendrocyte progenitor cells (OPCs) is an essential process during development that leads to uniform oligodendrocyte distribution and sufficient myelination for central nervous system function. Here, we demonstrate that the AMPA receptor (AMPAR) subunit GluR4A is an important driver of OPC migration and myelination in vivo and that activated voltage-gated calcium channels are downstream of glutamate receptor signaling in mediating this migration.  相似文献   
53.
Autosomal dominant leukodystrophy (ADLD) is an adult onset demyelinating disorder that is caused by duplications of the lamin B1 (LMNB1) gene. However, as only a few cases have been analyzed in detail, the mechanisms underlying LMNB1 duplications are unclear. We report the detailed molecular analysis of the largest collection of ADLD families studied, to date. We have identified the minimal duplicated region necessary for the disease, defined all the duplication junctions at the nucleotide level and identified the first inverted LMNB1 duplication. We have demonstrated that the duplications are not recurrent; patients with identical duplications share the same haplotype, likely inherited from a common founder and that the duplications originated from intrachromosomal events. The duplication junction sequences indicated that nonhomologous end joining or replication‐based mechanisms such fork stalling and template switching or microhomology‐mediated break induced repair are likely to be involved. LMNB1 expression was increased in patients’ fibroblasts both at mRNA and protein levels and the three LMNB1 alleles in ADLD patients show equal expression, suggesting that regulatory regions are maintained within the rearranged segment. These results have allowed us to elucidate duplication mechanisms and provide insights into allele‐specific LMNB1 expression levels.  相似文献   
54.
ObjectiveWeb-based self-management services remain underutilized in current practice. Our aim was to gain insight into disease and self-management experiences of patients in early and progressive stages of coronary heart disease (CHD), to understand moderating effects of daily life experiences on the utilization of web-based self-management services and preconditions for use.MethodsWe applied generative research techniques, which stem from the field of product design and are characterized by the use of creative processes. Three groups of patients with CHD received a sensitizing package to document and reflect on their health, and were subsequently either interviewed or participated in a focus group session.ResultsIn total, 23 patients participated in this study. Emerging themes were (1) fear for recurrent events, (2) experiences with professional care, (3) the perceived inability to prevent disease progression, (4) the desire to go on living without thinking about the disease every day, (5) the social environment as a barrier to or facilitator for self-management, and (6) the need for information tailored to personal preferences.ConclusionHow patients experience their disease varies between stable and post-acute stages, as well as between early and progressive stages of CHD. Patients in post-acute stages of the disease seem to be most amenable to support, while patients in stable stages want to live their life without being reminded of their disease. In the context of self-management, web-based services should be adapted to the variation in needs that occur in the different stages of CHD and new strategies to fit such services to these needs should be developed. Furthermore, they should be tailored to patients’ individual health situation and preferences, support patient empowerment, and manage expectations regarding the progression of their disease.  相似文献   
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