BACKGROUND:Poly(L-lactic acid) (PLLA) scaffold is a kind of widely used biomaterial in tissue engineering. However, low hydrophilicity and lack of surface cell recognition site of PLLA hinder its further application. OBJECTIVE:To study the biocompatibility of multi-walled carbon nanotubes/PLLA (MWCNTs/PLLA) nanofiber scaffolds with mouse neural stem cells in vitro. METHODS:Mouse neural stem cells were isolated. Then we used electrospinning to fabricate PLLA nanofibers and modified them with multi-walled carbon nanotubes. We assessed their biocompatibility with passage 3 mouse neural stem cells in vitro. RESULTS AND CONCLUSION:Scanning electron microscope showed that the neural stem cells could survive on both scaffolds. No cytotoxic effects were detected on both scaffolds by Cell Counting Kit-8 detection. The adhesion and proliferation abilities of neural stem cells on the MWCNTs/PLLA scaffold were significantly greater than those on the PLLA scaffold. Neural stem cells were found grow well and have normal morphology on both scaffolds under scanning electron microscope and by Hoechst 33342 staining. Besides, immunofluorescence staining showed MWCNTs/PLLA could promote neural stem cells to differentiate into mature neurons and neurites grew along with the nanofiber scaffold. In conclusion, the MWCNTs/PLLA nanofiber scaffold has better properties than the PLLA for transplanted cells and provides a good growth carrier for neural stem cells to be induced to differentiate into neurons, which is expected to have a great potential of applications in nerve tissue engineering.

Objective: To investigate the association between parenting style and sleep problems among school aged children with autism spectrum disorder (ASD). Methods: A total of 98 children with ASD aged 6-10 years old and 98 age and gender matched typically developing (TD) children from mainstream schools were recruited. Parenting style and sleep problems were measured via Parent Behavior Inventory (PBI) and Children s Sleep Habits Questionnaire(CSHQ), respectively. The symptom severity and intelligence level were also evaluated. Generalized linear model was used to analyze the relationship between parenting style and sleep problems. Results: There was no statistically significant difference in the parenting style of the two groups of children( P > 0.05 ); weekend sleep time of children with ASD was significantly shorter than that of the TD group [(9.1±0.7)(9.5±0.8)h, P < 0.01 ], and the score of sleep onset delay was significantly higher than that of the TD group[(1.8±0.7)(1.5±0.7), P <0.01]. However, there was no statistically significant difference in the incidence of total sleep problems and various problems between the two groups of children( P >0.05). The parental support/engagement of children with ASD was negatively associated with the total score of sleep problems( β=-2.68, 95%CI =-4.88--0.47), bedtime resistance ( β=-1.65, 95%CI =-2.54--0.77) and sleep anxiety( β=-1.01, 95%CI =-1.70--0.32). The parental hostility/coercion was positively correlated with score of daytime sleepiness( β=1.41, 95%CI =0.53-2.29)( P <0.05). Conclusion Parenting style of support/engagement is associated with lower sleep problems in children with ASD, while hostile/coercion is associated with higher sleep problems. It should be improve parental style to reduce the sleep problems in children with ASD.