Neuroscience
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The platelet-derived growth factor receptor-α (PDGFRα) principally mediates growth factor signals in oligodendroglial progenitors and is involved in oligodendrogenesis and myelinogenesis in the developing spinal cord. However, the role of PDGFRα in the developing forebrain remains relatively unknown. We established a conditional knockout mouse for the Pdgfra gene (N-PRα-KO) using a Nestin promoter/enhancer-driven Cre recombinase and examined forebrain development. ⋯ After the defective PDGFRα signal in the forebrain, these phenotypes were clearly different from those in the spinal cord that showed defective populations expansion and migration of oligodendroglial lineage and premature myelination, as previously described. In contrast, areas of severe hypomyelination were common to both anatomical sites. PDGFRα was critically involved in the myelination of the forebrain and may differently regulate oligodendroglial lineage between the forebrain and spinal cord.
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The application of resting state functional MRI (RS-fMRI) in Parkinson's disease (PD) was widely performed using standard statistical tests, however, the machine learning (ML) approach has not yet been investigated in PD using RS-fMRI. In current study, we utilized the mean regional amplitude values as the features in patients with PD (n = 72) and in healthy controls (HC, n = 89). The t-test and linear support vector machine were employed to select the features and make prediction, respectively. ⋯ Similar with previous neuroimaging studies in PD, the discriminative regions were mainly included the disrupted motor system, aberrant visual cortex, dysfunction of paralimbic/limbic and basal ganglia networks. The lateral parietal lobe, such as right inferior parietal lobe (IPL) and supramarginal gyrus (SMG), was detected as the discriminative features exclusively in Slow-4. Our findings, at the first time, indicated that the ML approach is a promising choice for detecting abnormal regions in PD, and a multi-frequency scheme would provide us more specific information.
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The ability to perceive differences in environmental contrast is critical for navigating complex environments safely. People with Parkinson's disease (PD) report a multitude of visual and cognitive deficits which may impede safe obstacle negotiation and increase fall risk. Enhancing obstacle contrast may influence the content of visual information acquired within complex environments and thus target environmental fall risk factors. 17 PD with a history of falls and 18 controls walked over an obstacle covered in a high and low contrast material in separate trials whilst eye movements were recorded. ⋯ Better executive function was associated with spending longer looking at the low contrast obstacle and at the ground beyond the high contrast obstacle. Enhancing the contrast of ground-based trip hazards may improve visual processing of environmental cues in PD, particularly for individuals with better executive function. Manipulating contrast to attract visual attention is already in use in the public domain, however its utility for reducing fall risk in PD is yet to be formally tested in habitual settings.