ABSTRACT
Objective:To investigate the role of perceived social support and self-esteem between the passive social network site use and depression among college students.Methods:Totally 1 393 college students were investigated by social website use scale, perceived social support scale, self-esteem scale and center for epidemiologic studies depression scale. SPSS 20.0 and Amos 21.0 softwares were used for descriptive analysis, Pearson correlation analysis, mediating effect test and structural equation model construction.Results:The total scores of passive social network site use, perceived social support, self-esteem and depression were (13.96±3.47), (61.04±12.03), (27.28±4.35) and (31.18±8.74) respectively. The scores of passive social network site use group in perceived social support (60.03±12.25), self-esteem (27.03±4.34) and depression (31.53±9.06) were statistically different with those in the active social network site use group (perceived social support (63.61±11.03), self-esteem (27.91±4.31) and depression (30.31±7.82), t=-5.04, P<0.01, t=-3.39, P=0.001, t=2.35, P=0.019). After controlling gender variables, the use of passive social network sites was positively correlated with depression ( r=0.053, P<0.01), while negatively correlated with perceived social support and self-esteem ( r=-0.157, -0.088, P<0.01). Perceived social support was positively correlated with self-esteem ( r=0.45, P<0.01). Perceived social support and self-esteem played a partial mediating role between passive social network site use and depression. The mediating effect includes two paths: one was the separate mediating effect of social support, and the other was the chain mediating effect of perceived social support and self-esteem, which accounted for 27% and 25% of the total effect respectively. Conclusion:The use of passive social networking sites can indirectly affect depression through the perceived social support or the chain mediating of social support and self-esteem.
ABSTRACT
Objective To investigate the effect of cogl410 on brain edema around lesion foci after traumatic brain edema (TBI) in mice and possible mechanism.Methods APOE-knockout TBI mice (n =130) were divided into cog1410 group and saline group according to the random number table,with 65 mice per group.Several time points (0,1,3,5,and 7 days) after TBI,13 mice were sacrificed in each group.TBI was induced with controlled cortex injury to the mice.A single injection of cog1410 solution or saline was administered via the caudal vein in 30 minutes after TBI.Levels of aquaporin-4 (AQP-4) around the lesion tissues were measured using the Western blot and q-PCR methods.Brain water content was determined by the dry-wet weight method.Results Brain water content in cog1410 group and saline group increased after TBI,reached the peak at day 3 [(81.184 ±0.009)％ vs (84.184 ± 0.014) ％] and normalized at day 7 [(76.018 ± 0.003) ％ vs (77.790 ± 0.012) ％] (P ＜ 0.05).There were almost no changes in AQP-4 mRNA expression in saline group after TBI.Whereas in cog1410 group,AQP-4 mRNA was greatly down-regulated at day 3 (0.278 ±0.014),increased greatly at days 5 and 7 after TBI (1.744 ± 0.014,1.782 ± 0.003) (P ＜ 0.05).Level of AQP-4 protein in saline group was increased at day 1 (0.491 ±0.060),reached the peak (0.605 ±0.099),and gradually returned to the preinjury level at days 5 and 7 (0.434 ± 0.042,0.358 ± 0.034).By contrast,level of AQP-4 protein in cog1410 group revealed no notable changes at day 1,slight increase at day 3,significant increase at day5 (1.079±0.090),and apeak at day7 (1.247±0.210) (P＜0.05).Conclusion cog1410 can significantly alleviate brain edema around the lesion foci of mice with TBI,as may be achieved by altering the mRNA and protein levels of AQP-4.