Neuroscience
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Stroke is a major life-threatening and disabling disease with a restricted therapeutic approach. Bone marrow stromal cells (BMSCs) possess proliferative ability and a multi-directional differentiation potential, and secrete a range of trophic/growth factors that can protect neurons after cerebral ischemia/reperfusion. Transient receptor potential canonical (TRPC) is a family of non-selective channels permeable to Ca2+, with several functions including neuronal survival. ⋯ In the present study, we report that over-expression of TRPC6 via a CRISPR-based synergistic activation mediator in BMSCs provided a greater reduction of brain injury in a rat model of ischemia/reperfusion. Further, the improved neurofunctional outcomes were associated with increased TRPC6 and brain derived neurotrophic factor expression levels. Overall, these data suggest that TRPC6 over-expressing BMSCs may be a promising therapeutic agent for ischemic stroke.
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Understanding brain processing mechanisms from the perception of speech sounds to high-level semantic processing is vital for effective human-robot communication. In this study, 128-channel electroencephalograph (EEG) signals were recorded when subjects were listening to real and pseudowords in Mandarin. By using an EEG source reconstruction method and a sliding-window Granger causality analysis, we analyzed the dynamic brain connectivity patterns. ⋯ This may be related to semantic processing and integration. The involvement of both bottom-up input and top-down modulation in real word processing may support the previously proposed TRACE model. In sum, the findings of this study suggest that representations of speech involve dynamic interactions among distributed brain regions that communicate through time-specific functional networks.
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We have recently shown that the efficiency of stopping a response is correlated with GABAergic activity in primary motor cortex (M1) measured using the short interval intracortical inhibition (SICI) protocol. However, this finding was observed when SICI was measured in left M1 and when stopping efficiency was measured with a bimanual response task. The aim of the present study was to examine the extent to which the relationship between SICI and stopping is lateralized to the hemisphere controlling the response (e.g. left M1 and stopping a right hand response) and/or reflects bilateral inhibitory mechanisms (as might be seen between left M1 and left hand stopping). ⋯ We found that SICI was significantly correlated between hemispheres (r = 0.51) and stopping efficiency was correlated between hands (r = 0.77). When controlling for other relevant variables, we found that stopping efficiency in each hand was uniquely predicted by SICI in the contralateral hemisphere, but not the ipsilateral hemisphere. These results suggest that there is a hemispheric-specific contribution of SICI to stopping efficiency.
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Understanding and predicting the intentions of others through limb movements are vital to social interaction. The processing of biological motion is unique from the processing of motion of inanimate objects. Presently, there is controversy over whether visual consciousness of biological motion is regulated by visual attention. ⋯ Late processing was localized to frontal-parietal regions, such as the right dorsal superior frontal gyrus, the left medial superior frontal gyrus, and the occipito-temporal regions. Congruency-related processing occurred in the 246-260-ms window and was localized to the right superior occipital gyrus. In summary, due to its complexity, biological motion awareness has a unique neural basis.
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Signal processing in the principal neurons of the anteroventral cochlear nucleus (AVCN) is modulated by glycinergic inhibition. The kinetics of IPSCs are specific to the target neurons. It remains unclear what glycine receptor subunits are involved in generating such target-specific IPSC kinetics in AVCN principal neurons. ⋯ To further identify the cell type-specific expression patterns of GlyRα subunits, we combined whole-cell patch clamp recording with immunohistochemistry by recording from all three types of AVCN principal neurons, characterizing the synaptic properties of their glycinergic inhibition, dye-filling the neurons, and processing the slice for immunostaining of different GlyRα subunits. We found that AVCN bushy neurons express both GlyRα1 and GlyRα4 subunits that underlie their slow IPSC kinetics, whereas both T-stellate and D-stellate neurons express only GlyRα1 subunit that underlies their fast IPSC kinetics. In conclusion, AVCN principal neurons express cell-type specific GlyRα subunits that underlie their distinct IPSC kinetics, which enables glycinergic inhibition from the same source to exert target cell-specific modulation of activity to support the unique physiological function of these neurons.