Altered extracellular amino acid concentrations following concussion or mild traumatic brain injury can result in delayed neuronal damage through overactivation of NMDA glutamatergic receptors. However, the consequences of repeated concussions prior to complete recovery are not well understood. In this study, we utilized in vivo cerebral microdialysis and a weight-drop model to investigate the acute neurochemical response to single and repeated concussions in adult rats that were fully conscious.
View Article and Find Full Text PDFPurpose: Using a longitudinal design, this study aimed to describe inferential comprehension abilities of neglected French-speaking preschool children from 42 to 66 months of age in comparison to non-neglected peers, to examine the association with receptive vocabulary, and to determine whether rates of change in inferential abilities over time was stable between the two group conditions.
Method: An inferential comprehension task and the French version of the Peabody Picture Vocabulary Test-Fourth Edition were administered to a group of neglected children ( = 37-40) and to a group of same-age non-neglected children ( = 71-91) at 42, 54, and 66 months old, as part of the Early Longitudinal Language and Neglect study.
Results: Results show that children exposed to neglect obtain significantly lower scores compared to their same-age peers on inferential comprehension and receptive vocabulary measures at all three time points ( < .
Theory and studies support that educational quality may differ according to socio-political context even in states with similar cultures. Based on a secondary analysis of data, this study aims at identifying latent profiles of adult-child interaction quality in groups of three-year-old children in Quebec's (Canada) early childhood centers and France's kindergarten classrooms using the CLASS Pre-K. This study also aims to explore existing associations between identified profiles, socio-political contexts, and structural characteristics (staff qualifications, ages, group size).
View Article and Find Full Text PDFObjective: Alterations in amino acid concentrations are a major contributor to the persistent neurological and behavioral effects induced by concussions and mild traumatic brain injuries (TBIs). Glutamate, the most abundant excitatory amino acid in the CNS, has a major role in the pathophysiological process of concussion. The indiscriminate liberation of glutamate immediately after a concussion triggers an excitotoxic response that leads to cell death, neuronal damage, and the dysfunction of surviving neurons, largely by overactivation of N-methyl-d-aspartate (NMDA) glutamatergic receptors.
View Article and Find Full Text PDFThe p14 protein is a well-known regulator of p53-dependent and p53-independent tumor-suppressive activities. In unstressed cells, p14 is predominantly sequestered in the nucleoli, bound to its nucleolar interaction partner NPM. Upon genotoxic stress, p14 undergoes an immediate redistribution to the nucleo- and cytoplasm, where it promotes activation of cell cycle arrest and apoptosis.
View Article and Find Full Text PDFProtein arginine methyltransferase 6 (PRMT6) catalyses the asymmetric dimethylation of arginines on numerous substrate proteins within the human cell. In particular, PRMT6 methylates histone H3 arginine 2 (H3R2) which affects both gene repression and activation. However, the substrate specificity of PRMT6 has not been comprehensively analysed.
View Article and Find Full Text PDFSecondary brain injury following hemorrhagic shock (HS) is a frequent complication in patients, even in the absence of direct brain trauma, leading to behavioral changes and more specifically anxiety and depression. Despite preclinical studies showing inflammation and apoptosis in the brain after HS, none have addressed the impact of circulating mediators. Our group demonstrated an increased uric acid (UA) circulation in rats following HS.
View Article and Find Full Text PDFUnderstanding the feeding ecology of polar cod () during its first year of life is crucial to forecasting its response to the ongoing borealization of Arctic seas. We investigated the relationships between diet composition and feeding success in 1797 polar cod larvae and juveniles 4.5-55.
View Article and Find Full Text PDFBackground: Exposure to neglect can severely compromise children's pragmatic skills (social language use). The disruptions of parent-child interactions that typically occur in context of neglect may compromise several parental behaviors which are known to foster language skills such as pragmatics.
Objectives: 1- Compare the behaviors of neglectful and non-neglectful parents in four domains which are of interest for pragmatic language development, namely, responsive, supportive, affective, and control behaviors, and 2- Identify parental behaviors associated with the levels of pragmatic ability of 42-month-old neglected children.
Among the widespread and increasing number of identified post-translational modifications (PTMs), arginine methylation is catalyzed by the protein arginine methyltransferases (PRMTs) and regulates fundamental processes in cells, such as gene regulation, RNA processing, translation, and signal transduction. As epigenetic regulators, PRMTs play key roles in pluripotency, differentiation, proliferation, survival, and apoptosis, which are essential biological programs leading to development, adult homeostasis but also pathological conditions including cancer. A full understanding of the molecular mechanisms that underlie PRMT-mediated gene regulation requires the genome wide mapping of each player, i.
View Article and Find Full Text PDFLanguage is the most frequently compromised area of development in English-speaking neglected children, particularly the morphosyntactic component of language. This is very worrisome given its central role in academic success and social participation. No previous study has examined the morphosyntactic skills of French-speaking neglected children, despite the morphological richness of French.
View Article and Find Full Text PDFThe goals of this study were twofold: (1) to compare the pragmatic language skills (i.e., social communication skills) of 42-month-old neglected children with those of same-aged non-neglected children and (2) to measure the prevalence of pragmatic difficulties among the neglected children.
View Article and Find Full Text PDFBackground: Multiple organ failure can develop after hemorrhagic shock (HS). Uric acid (UA) is released from dying cells and can be proinflammatory. We hypothesized that UA could be an alternative mediator of organ apoptosis and inflammation after HS.
View Article and Find Full Text PDFBackground: Haemostasis and correction of hypovolemia are the pillars of early haemorrhage shock (HS) management. Vasopressors, which are not recommended as first-line therapy, are an alternative to aggressive fluid resuscitation, but data informing the risks and benefits of vasopressor therapy as fluid-sparing strategy is lacking. We aimed to study its impact on end organs, in the setting of a haemodynamic response to the initial volume resuscitation.
View Article and Find Full Text PDFProtein arginine methyltransferase 6 (PRMT6) catalyzes asymmetric dimethylation of histone H3 at arginine 2 (H3R2me2a). This mark has been reported to associate with silent genes. Here, we use a cell model of neural differentiation, which upon PRMT6 knockout exhibits proliferation and differentiation defects.
View Article and Find Full Text PDFAcute myeloid leukemia (AML) arises through clonal expansion of transformed myeloid progenitor cells. The proto-oncogene is highly upregulated in different solid tumors and leukemic cells, but little is known about its transcriptional regulation during leukemogenesis. MYB is an important hematopoietic transcription factor involved in proliferation as well as differentiation and upregulated in most human acute leukemias.
View Article and Find Full Text PDFProtein arginine methyltransferase 4 (PRMT4) is an essential epigenetic regulator of fundamental and conserved processes during vertebrate development, such as pluripotency and differentiation. Surprisingly, PRMT4 homologs have been identified in nearly all vertebrate classes except the avian genome. This raises the possibility that in birds PRMT4 functions are taken over by other PRMT family members.
View Article and Find Full Text PDFJ Speech Lang Hear Res
October 2016
Purpose: This study aimed to describe the development of inferential abilities of children age 3 to 6 years in a narrative using a dialogic reading task on an iPad.
Method: Participants were 121 typically developing children, divided into 3 groups according to age range (3-4 years old, 4-5 years old, 5-6 years old). Total score of inferential comprehension, subscores by causal inference type targeting elements of the story grammar, and quality of response were examined across groups.
Protein arginine methyltransferase 6 (PRMT6) catalyses asymmetric dimethylation of histone H3 at arginine 2 (H3R2me2a), which has been shown to impede the deposition of histone H3 lysine 4 trimethylation (H3K4me3) by blocking the binding and activity of the MLL1 complex. Importantly, the genomic occurrence of H3R2me2a has been found to coincide with histone H3 lysine 27 trimethylation (H3K27me3), a repressive histone mark generated by the Polycomb repressive complex 2 (PRC2). Therefore, we investigate here a putative crosstalk between PRMT6- and PRC-mediated repression in a cellular model of neuronal differentiation.
View Article and Find Full Text PDFResearch data show that exposure to abuse and neglect has detrimental effects on a child's language development. In this meta-analysis, we analyze studies (k = 23), to compare the language skills (receptive language, expressive language, pragmatics) of children who have experienced abuse and/or neglect with the language skills of children who have not experienced abuse and/or neglect and to examine whether age or type of maltreatment moderate the relationship between maltreatment and language skills. Results confirm that the language skills of children who have experienced abuse and/or neglect are delayed when compared to children who have not experienced abuse and/or neglect.
View Article and Find Full Text PDFBackground: The ability to make inferences plays a crucial role in reading comprehension and the educational success of school-aged children. However, it starts to unfold much earlier than school entry and literacy. Given that it is likely to be targeted in speech language therapy, it would be useful for clinicians to have access to information about a developmental sequence of inferential comprehension.
View Article and Find Full Text PDFSeveral studies suggest that pragmatic skills (PS) (i.e., social communication) deficits may be linked to executive dysfunction (i.
View Article and Find Full Text PDFProtein arginine methyltransferase 4 (PRMT4)-dependent methylation of arginine residues in histones and other chromatin-associated proteins plays an important role in the regulation of gene expression. However, the exact mechanism of how PRMT4 activates transcription remains elusive. Here, we identify the chromatin remodeller Mi2α as a novel interaction partner of PRMT4.
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