Introduction: Early focal brain injuries lead to long-term disabilities with frequent cognitive impairments, suggesting global dysfunction beyond the lesion. While plasticity of the immature brain promotes better learning, outcome variability across individuals is multifactorial. Males are more vulnerable to early injuries and neurodevelopmental disorders than females, but long-term sex differences in brain growth after an early focal lesion have not been described yet.
View Article and Find Full Text PDFBackground: Childhood severe traumatic brain injury (TBI) is a leading cause of long-lasting acquired disability, but predicting long-term functional outcome remains difficult.
Objectives: This study aimed to 1) describe the functional outcome at 1 and 7 years post-TBI; 2) determine the initial and concurrent factors associated with long-term outcome; and 3) evaluate the predictive value of functional status, overall disability level and intellectual ability measured at 1 year post-injury to determine 7-year clinically meaningful outcomes.
Methods: Among the children (<16 years) consecutively included over 3 years in the Traumatisme Grave de l'Enfant (TGE) prospective longitudinal cohort study after accidental severe TBI, we studied the outcomes of 39 survivors at 1 and 7 years post-injury.
Despite growing evidence of links between sulcation and function in the adult brain, the folding dynamics, occurring mostly before normal-term-birth, is vastly unknown. Looking into the development of cortical sulci in infants can give us keys to address fundamental questions: what is the sulcal shape variability in the developing brain? When are the shape features encoded? How are these morphological parameters related to further functional development? In this study, we aimed to investigate the shape variability of the developing central sulcus, which is the frontier between the primary somatosensory and motor cortices. We studied a cohort of 71 extremely preterm infants scanned twice using MRI - once around 30 weeks post-menstrual age (w PMA) and once at term-equivalent age, around 40w PMA -, in order to quantify the sulcus's shape variability using manifold learning, regardless of age-group or hemisphere.
View Article and Find Full Text PDFGrasping is one of the first dominant motor behaviors that enable interaction of a newborn infant with its surroundings. Although atypical grasping patterns are considered predictive of neuromotor disorders and injuries, their clinical assessment suffers from examiner subjectivity, and the neuropathophysiology is poorly understood. Therefore, the combination of technology with functional magnetic resonance imaging (fMRI) may help to precisely map the brain activity associated with grasping and thus provide important insights into how functional outcomes can be improved following cerebral injury.
View Article and Find Full Text PDFBackground: Childhood severe traumatic brain injury (TBI) is a leading cause of long-lasting acquired disability, but little is known about functional outcome.
Objective: We aimed to 1) study clinical recovery and functional outcome over 24 months after severe childhood TBI, 2) identify early sociodemographic and severity factors influencing outcome, and 3) examine the clinical utility of the Pediatric Injury Functional Outcome Scale (PIFOS) to assess functional outcome.
Methods: Children (0-15 years) consecutively admitted in a trauma centre after accidental severe TBI over 3 years were included in a prospective longitudinal study (Traumatisme Grave de l'Enfant cohort).
Unlabelled: It is now widely accepted that compensatory mechanisms are involved during the early phase of Parkinson's disease (PD) to delay the expression of motor symptoms. However, the neurochemical mechanisms underlying this presymptomatic period are still unclear. Here, we measured in vivo longitudinal changes of both the dopaminergic and serotonergic systems in seven asymptomatic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated monkeys (when motor symptoms are less apparent) using PET.
View Article and Find Full Text PDFSerotonergic (5-HT) neurons degenerate in Parkinson's disease. To determine the role of this 5-HT injury-besides the dopaminergic one in the parkinsonian symptomatology-we developed a new monkey model exhibiting a double dopaminergic/serotonergic lesion by sequentially using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 3,4-methylenedioxy-N-methamphetamine (MDMA, better known as ecstasy). By positron emission tomography imaging and immunohistochemistry, we demonstrated that MDMA injured 5-HT nerve terminals in the brain of MPTP monkeys.
View Article and Find Full Text PDFThe cardinal symptoms of Parkinson's disease (PD), akinesia, rigidity and tremor, are only observed when the striatal level of dopamine (DA) is decreased by 60-80%. It is likely that compensatory mechanisms during the early phase of DA depletion delay the appearance of motor symptoms. In a previous study, we proposed a new PD monkey model with progressive MPTP intoxication.
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