Neuroscience
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MicroRNA (miRNA) is a small non-coding RNA that regulates gene expression by degrading target mRNAs or inhibiting translation. Although many miRNAs play important roles in various conditions, it is unclear whether miRNAs are involved in motor nerve regeneration. ⋯ Furthermore, the luciferase assay and in vitro gain of function methods supported that both genes could be potent targets of miR-124. These results suggest that injury-induced repression of miR-124 may be implicated in the regulation of expression of several injury-associated transcription factors, which are crucial for appropriate nerve regeneration.
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Verbal insight problem solving means to break mental sets, to select the novel semantic information and to form novel, task-related associations. Although previous studies have identified the brain regions associated with these key processes, the interaction among these regions during insight is still unclear. ⋯ Compared with noninsight solution, insight solution had a stronger functional connectivity between the inferior frontal gyrus and middle temporal gyrus in the right hemisphere. Our study reveals the neural pathway of information processing during verbal insight problem solving, and supports the right-hemisphere advantage theory of insight.
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Parkinson's disease (PD) is the second most frequent neurodegenerative disorder afflicting 2% of the population older than 65 years worldwide. Recently, brain organotypic slices have been used to model neurodegenerative disorders, including PD. They conserve brain three-dimensional architecture, synaptic connectivity and its microenvironment. ⋯ In addition, a significant decline of medium spiny neuron density was observed from days 7 to 16. These sagittal organotypic slices could be used to study the early stage of PD, namely dopaminergic degeneration, and the late stage of the pathology with dopaminergic and GABAergic neuron loss. This novel model might improve the understanding of PD and may represent a promising tool to refine the evaluation of new therapeutic approaches.
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This study investigates the role of phonology in reading logographic Chinese. Specifically, whether phonological information is obligatorily activated in reading Chinese two-character compounds was examined using the masked-priming paradigm with event-related potential (ERP) recordings. Twenty-two native Cantonese Chinese speakers participated in a lexical decision experiment. ⋯ In addition, attenuation in ERP amplitudes was found in the Semantic-related condition in the window of 250-500 ms (N400). However, no significant results (neither behavioral nor ERP) were found in the Syllable-related condition. These results suggest that phonological activation is not mandatory and the role of phonology is minimal at best in reading Chinese two-character compounds.
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Autophagy is responsible for the bulk degradation of cytoplasmic contents including organelles through the lysosomal machinery. Neonatal hypoxia-ischemia (HI) causes cell death in the brain by caspase-dependent and independent pathways. Ischemic insults also increase the formation of autophagosomes and activate autophagy. ⋯ In the hippocampus, both HI males and all females had increased numbers of autolysosomes suggesting activation of autophagy but with no effect on lysosome numbers, or Beclin-1 or LC3B protein levels. Males and females had increases in caspase 3/7 activity in their cortices and hippocampi following HI, though the increases were three to sixfold greater in females. The present data: (a) confirm greater caspase activation in the brains of females compared to males following HI; (b) suggest a partial failure to degrade LC3B-II protein in cortical but not hippocampal lysosomes of females as compared to males following neonatal HI; (c) all females have greater basal autophagy activity than males which may protect cells against injury by increasing cell turnover and (d) demonstrate that autophagy pathways are disturbed in regional- and sex-specific patterns in the rat brain following neonatal HI.