Search results for "Corpus Callosum"
showing 10 items of 66 documents
Phenotype associated with TAF2 biallelic mutations: a clinical description of four individuals and review of the literature
2021
International audience; Transcription factor IID is a multimeric protein complex that is essential for the initiation of transcription by RNA polymerase II. One of its critical components, the TATA-binding protein-associated factor 2, is encoded by the gene TAF2. Pathogenic variants of this gene have been shown to be responsible for the Mental retardation, autosomal recessive 40 syndrome. This syndrome is characterized by severe intellectual disability, postnatal microcephaly, pyramidal signs and thin corpus callosum. Until now, only three families have been reported separately. Here we report four individuals, from two unrelated families, who present with severe intellectual disability and…
Frequency and phenotype of SPG11 and SPG15 in complicated hereditary spastic paraplegia
2009
Background: Hereditary spastic paraplegias (HSP) are clinically and genetically highly heterogeneous. Recently, two novel genes, SPG11 ( spatacsin ) and SPG15 ( spastizin ), associated with autosomal recessive HSP, were identified. Clinically, both are characterised by complicated HSP and a rather similar phenotype consisting of early onset spastic paraplegia, cognitive deficits, thin corpus callosum (TCC), peripheral neuropathy and mild cerebellar ataxia. Objective: To compare the frequency of SPG11 and SPG15 in patients with early onset complicated HSP and to further characterise the phenotype of SPG11 and SPG15. Results: A sample of 36 index patients with early onset complicated HSP and …
Physical Activity Predicts Population-Level Age-Related Differences in Frontal White Matter
2018
Physical activity has positive effects on brain health and cognitive function throughout the life span. Thus far, few studies have examined the effects of physical activity on white matter microstructure and psychomotor speed within the same, population-based sample (critical if conclusions are to extend to the wider population). Here, using diffusion tensor imaging and a simple reaction time task within a relatively large population-derived sample (N = 399; 18–87 years) from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN), we demonstrate that physical activity mediates the effect of age on white matter integrity, measured with fractional anisotropy. Higher self-reported daily ph…
Both rare and de novo copy number variants are prevalent in agenesis of the corpus callosum but not in cerebellar hypoplasia or polymicrogyria.
2013
Agenesis of the corpus callosum (ACC), cerebellar hypoplasia (CBLH), and polymicrogyria (PMG) are severe congenital brain malformations with largely undiscovered causes. We conducted a large-scale chromosomal copy number variation (CNV) discovery effort in 255 ACC, 220 CBLH, and 147 PMG patients, and 2,349 controls. Compared to controls, significantly more ACC, but unexpectedly not CBLH or PMG patients, had rare genic CNVs over one megabase (p = 1.48×10−3; odds ratio [OR] = 3.19; 95% confidence interval [CI] = 1.89–5.39). Rare genic CNVs were those that impacted at least one gene in less than 1% of the combined population of patients and controls. Compared to controls, significantly more AC…
Lithium and GSK3-β promoter gene variants influence white matter microstructure in bipolar disorder
2013
Lithium is the mainstay for the treatment of bipolar disorder (BD) and inhibits glycogen synthase kinase 3-beta (GSK3-beta). The less active GSK3-beta promoter gene variants have been associated with less detrimental clinical features of BD. GSK3-beta gene variants and lithium can influence brain gray matter structure in psychiatric conditions. Diffusion tensor imaging (DTI) measures of white matter (WM) integrity showed widespred disruption of WM structure in BD. In a sample of 70 patients affected by a major depressive episode in course of BD, we investigated the effect of ongoing long-term lithium treatment and GSK3-beta promoter rs334558 polymorphism on WM microstructure, using DTI and …
Corpus callosum function in verbal dichotic listening: inferences from a longitudinal follow-up of Relapsing-Remitting Multiple Sclerosis patients.
2009
This study conducted a follow-up of 13 early-onset slightly disabled Relapsing-Remitting Multiple Sclerosis (RRMS) patients within an year, evaluating both CC area measurements in a midsagittal Magnetic Resonance (MR) image, and Dichotic Listening (DL) testing with stop consonant vowel (C-V) syllables. Patients showed a significant progressive loss of posterior CC areas (isthmus and splenium) related to increasing EDSS scores and an enhancing right ear advantage (REA) over time. A significant correlation between posterior CC areas and DL scores emerged in both evaluations, being negative for the right and positive for the left ear. The pattern of correlations suggests that the CC can serve …
Endoscope-assisted microsurgery for tumors of the septum pellucidum: surgical considerations and benefits of the method in the treatment of four seri…
2003
Neoplasms that primarily originate from the septum pellucidum are extremely rare. Generally the septum pellucidum is involved in direct extension of tumors that arise from the neighboring structures, principally the corpus callosum. Endoscope-assisted techniques form a useful adjunct to common microsurgical procedures to completely remove intraventricular lesions. There are two main advantages of endoscope-assisted surgery over common microsurgical techniques: reduction of superficial brain retraction with less iatrogenic trauma to the neighboring structures and inspection of hidden corners depict simultaneously anatomical details which are not precisely visible in the zoomed and thus light…
Developmental dyslexia: re-evaluation of the corpus callosum in male adults.
2000
Using a new method based upon the measurement of four angles, we analyzed the corpus callosum of 23 adult male dyslexics and 25 age-matched controls on MRI sagittal scans. Two out of the four angles measured showed significant differences between the groups that are consistent with previous findings concerning the size of the corpus callosum in dyslexics. In particular, posterior regions are concerned, displaying a lowered corpus callosum in dyslexics. These findings are discussed in relation to cortical parietal asymmetries and possible hormonal events, referring to the testosterone hypothesis, that could occur in utero or in the perinatal period in the dyslexic population.
Broad disruption of brain white matter microstructure and relationship with neuropsychological performance in male patients with severe alcohol depen…
2012
Aims In the last years, refined magnetic resonance diffusion tensor imaging (DTI) methods have become available to study microstructural alterations in the human brain. We investigated to what extent white matter tissue abnormalities are present in male patients after chronic, excessive alcohol consumption and if these alterations are correlated with measures of alcohol consumption and neuropsychological performance. Methods Twenty-four detoxified adult male patients with severe alcohol dependence and 23 healthy male control subjects were included in the study. Neuropsychological tests were assessed for executive function, attention, memory and visuospatial function. DTI was acquired and pr…
Disruption of White Matter Integrity in Bipolar Depression as a Possible Structural Marker of Illness
2011
Background: Diffusion tensor imaging allows the study of integrity of white matter (WM) tracts. Literature suggests that WM integrity could be altered in bipolar disorder. Heterogeneity of brain imaging methods, the studied samples, and drug treatments make localization, nature, and severity of the WM abnormalities unclear. Methods: We applied tract-based spatial statistics of diffusion tensor imaging measures to compare fractional anisotropy (FA), mean, and radial diffusivity of the WM skeleton in a group of 40 consecutively admitted inpatients affected by a major depressive episode without psychotic features with a diagnosis of bipolar disorder type I and 21 unrelated healthy volunteers f…