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Our objective is to study the relationship between the regulatory proteins Bcl-2/Bax and mitochondria-mediated apoptosis during the differentiation of adipose-derived stromal cells (ADSCs) into neurons. Immunocytochemistry and western blotting showed that the cells weakly expressed neuron-specific enolase (NSE) in the non-induced group and expressed NSE more strongly in the groups induced for 1 h, 3 h, 5 h and 8 h. NSE expression peaked at 5 h (P < 0.05), although there was no significant difference between 5 and 8 h (P > 0.05). Bcl-2 expression gradually decreased over time in the non-induced group (P < 0.05). However, Bax, caspase-9, Cyt-c and caspase-3 expression gradually increased and peaked at 8 h (P < 0.05). Transmission electron microscopy revealed karyopyknosis, chromatin edge setting, mitochondria swelling and cavitation in cells at 5 h, and the mitochondrial membrane potential decreased over time, as demonstrated by laser scanning confocal microscopy. After a 5 h induction, cells differentiated into typical neurons and expressed Bcl-2, which inhibited apoptosis. Bax showed a strong apoptosis-promoting capacity, leading to changes in the mitochondrial membrane potential and structure, and then triggered the caspase-independent apoptotic response through the mitochondrial pathway. At the same time, Cyt-c was directly or indirectly released from the mitochondria to the cytoplasm to trigger the caspase-dependent apoptotic response through the mitochondrial pathway. Therefore, Bcl-2/Bax play an important role in regulating caspase-dependent and caspase-independent apoptosis mediated by the mitochondrial pathway during the differentiation of ADSCs into neurons.

Peer victimization is a serious issue among school-aged children. Chinese left-behind children tend to experience peer victimization and associated nonsuicidal self-injury (NSSI) behavior. However, the possible improvement of subjective socioeconomic status (SES) based on increased family income may serve to buffer the relationship between peer victimization and NSSI, and this buffering effect may differ by level of social support. Thus, the current study aimed to examine the moderating effect of subjective SES on the relationship between peer victimization and NSSI by the level of social support among Chinese left-behind children. A total of 431 left-behind children and 447 non-left-behind children (comparison group) completed self-report scales measuring peer victimization, NSSI, subjective SES, and social support. Results showed that peer victimization was positively related to NSSI among left-behind children, but not among non-left-behind children. Moreover, for left-behind children with low levels of social support, high subjective SES intensified the association between peer victimization and NSSI; peer victimization was positively associated with NSSI among left-behind children who reported high subjective SES, but not among those with low subjective SES. However, high levels of social support seemed to protect the left-behind children with high subjective SES who experienced peer victimization from NSSI. For non-left-behind children with both parents present, high subjective SES played a protective role in the association between peer victimization and NSSI, regardless of the levels of social support they enjoyed. These findings contribute to an understanding of subjective SES as a moderating mechanism in the association between peer victimization and NSSI among left-behind children. Social support proved central to the protective role of subjective SES. Intervention programs to enhance social support can help to strengthen the protective effect of subjective SES on NSSI among left-behind children who experience peer victimization.

Background Non-suicidal self-injury (NSSI) has become a worldwide health concern, especially for the disadvantaged group such as Chinese rural-to-urban migrant children. Peer victimization is a risk factor for NSSI and is quite common among Chinese migrant children. However, few studies that focused on this group have paid attention to the relationship between peer victimization and NSSI. The current study addressed this gap in the literature by examining the mediating role of depressive symptoms and the moderating role of stressful life events in the relationship between peer victimization and NSSI in male and female migrant children. Methods A total of 650 migrant children completed self-report surveys that addressed peer victimization, NSSI, depressive symptoms, and stressful life events. Results Results showed that peer victimization was significantly related to NSSI for both migrant girls and boys. Depressive symptoms mediated the relationship between peer victimization and NSSI among girls, but not among boys. Additionally, stressful life events significantly moderated the relationships between depressive symptoms and NSSI and between peer victimization and NSSI among girls; higher levels of depressive symptoms or peer victimization coupled with more stressful life events related to a higher probability of NSSI. For boys, stressful life events moderated the relationship between peer victimization and NSSI; higher levels of peer victimization combined with increased NSSI behaviors among the boys who reported more stressful life events. Conclusions These findings contribute to the understanding of the mechanisms that inform the relationship between peer victimization and NSSI. Moreover, they indicate that future interventions can be enhanced by targeting depressive symptoms among girls and stressful life events among both girls and boys.

Parental involvement in adolescents' learning has been linked to high academic achievement, yet few studies have examined its reverse relationship at the same time and the potential mechanisms that underly these associations. To address this research gap, this study investigated the reciprocal relationship between parental involvement and academic achievement as well as the mediating role of adolescents' academic engagement among Chinese adolescents. In addition, the current study explored whether these relationships varied by gender. Using a longitudinal design, a total of 2381 secondary school students (48.8% girls, Mage = 13.38 ± 0.59) participated in the study. The results found significant positive directional effects from academic achievement to parental involvement among total sample, but not vice versa. The cross-lagged effect from academic achievement to parental involvement only existed among adolescent girls. Bootstrap analyses in the total sample revealed that parental involvement was related to academic achievement through the indirect effects of adolescents' behavioral engagement. In terms of gender differences, behavioral engagement totally mediated the path from academic achievement to parental involvement for boys, while no significant mediation effect was found for girls. These results have provided empirical evidence of the evocative role of adolescents' academic characteristics on parenting behaviors and the double-edged effect of parental involvement on adolescents' academic performance, they also suggest that further research is needed to explore effective and appropriate ways for parents to get involved in adolescents' learning in order to promote their children's academic achievement.

The C 2 -α-mannosyl-tryptophan amino acid is produced by a unique posttranslational modification (PTM) of proteins and poses a significant synthetic challenge. A new strategy based on Pd-catalyzed auxiliary-directed remote C-H glycosylation of tryptophan was developed, which generates the C 2 -α-mannopyranose (Man)-Trp unit in a highly efficient and stereoselective fashion. Density functional theory (DFT) computational studies support a concerted oxidative addition mechanism for the stereospecific functionalization of a Pd(II) palladacycle intermediate with an α-mannosyl chloride donor. The utility of this method was demonstrated in the first total synthesis of insect C-glycopeptide hormone Cam-HrTH-I.

Despite the significant progress in carbohydrate chemistry, there remains a pressing need for efficient and practical glycosylation methods using simple glycosyl donors and with high atom economy. Herein, a new protocol for glycosylation with glycosyl chloride donors under palladium-catalyzed conditions is developed. Pd II complex serves as a Lewis acid to promote the activation of glycosyl chloride for the formation of oxocarbenium ion intermediate. This new method is operationally simple, robust, and enables efficient synthesis of both Oand N-glycosides with a broad substrate scope. In particular, it offers an easy access to a range of N-ribonucleoside analogs.

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