Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917816 (mental retardation)
 15,867 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fragile X syndrome (FraX), a genetic neurodevelopmental disorder, results in impaired cognition with particular deficits in executive function and visuo-spatial skills. Here we report the first detailed 3D maps of the effects of the Fragile X mutation on brain structure, using tensor-based morphometry. TBM visualizes structural brain deficits automatically, without time-consuming specification of regions-of-interest. We compared 36 subjects with FraX (age: 14.66+/-1.58 S.D., 18 females/18 males), and 33 age-matched healthy controls (age: 14.67+/-2.2 S.D., 17 females/16 males), using high-dimensional elastic image registration. All 69 subjects' 3D T1-weighted brain MRIs were spatially deformed to match a high-resolution single-subject average MRI scan in ICBM space, whose geometry was optimized to produce a minimal deformation target. Maps of the local Jacobian determinant (expansion factor) were computed from the deformation fields. Statistical maps showed increased caudate (10% higher; p = 0.001) and lateral ventricle volumes (19% higher; p = 0.003), and trend-level parietal and temporal white matter excesses (10% higher locally; p = 0.04). In affected females, volume abnormalities correlated with reduction in systemically measured levels of the Fragile X mental retardation protein (FMRP; Spearman's r < -0.5 locally). Decreased FMRP correlated with ventricular expansion (p = 0.042; permutation test), and anterior cingulate tissue reductions (p = 0.0026; permutation test) supporting theories that FMRP is required for normal dendritic pruning in fronto-striatal-limbic pathways. No sex differences were found; findings were confirmed using traditional volumetric measures in regions of interest. Deficit patterns were replicated by performing statistics after logarithmic transformation, which may be more appropriate for tensor-valued data. Investigation of how these anomalies emerge over time will accelerate our understanding of FraX and its treatment.
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PMID:3D pattern of brain abnormalities in Fragile X syndrome visualized using tensor-based morphometry. 1716 22

Startle seizures belong to reflex epilepsy syndromes. They usually occur in patients with mental deficiency and showing widely extended cortical lesions, often involving the sensorimotor area. Here we report three cases who did not fulfill these criteria, and in whom stereotactic electroencephalography (SEEG) recordings demonstrated the prominent involvement of the supplementary motor area (SMA). Visual analysis was complemented by time-frequency analysis of SEEG signals using a neuroimaging approach (Epileptogenicity Maps), which showed at seizure onset a significant increase of high frequency oscillations (HFOs, 60-100 Hz) over the premotor and prefrontal areas. Critically, in all cases, the SMA showed ictal HFOs at seizure onset and was included in the surgical resection. All patients became seizure-free after surgery, and histopathological examinations showed no specific lesion. These cases suggest the prominent but not exclusive role of SMA in startle seizures, and highlight the fact that surgery can be considered even in the absence of any magnetic resonance imaging (MRI) lesion.
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PMID:The pivotal role of the supplementary motor area in startle epilepsy as demonstrated by SEEG epileptogenicity maps. 2490 65