Objective To investigate the role of demyelination and the alteration of chondrotin sulfate proteoglycan (CSPG,NG2) expression after compression injury of the spinal cord (CSCI).Methods Seventy-five adult Sprague-Dawley rats were randomly divided into a normal group,a sham-operation group,a CSCI 1 day group,a CSCI 3 day group,and a CSCI 7 day group.There were 15 rats in each group.The injuries in the CSCI groups were inflicted using a technique devised in our laboratory.Basso-Beattie-Bresnahan (BBB) neurological function assessment was used to assess the rats' motor function,osmic acid staining and transmission electronic microscopy (TEM)were used to observe any pathological changes of myelinated nerve fibers in the white matter at 1,3 and 7 days after CSCI.The amount of myelinated nerve fibers in the posterior funiculus of the spinal cord and the ratio of myelin sheath thickness to axon diameter (the G-ratio) were calculated.Any alteration in NG2 expression was observed by Western blotting.Results The average neurological function assessment scores in the CSCI groups were (1.23 ±0.45),(0.65 ± 0.35) and (0.00 ± 0.00) respectively.Compared with the normal group (21.00 ± 0.00) and the sham operation group (21.00 ± 0.00),the differences were all statistically significant.The rats' motor function deteriorated gradually with time after the CSCI.Osmic acid staining showed that the white matter was intact in the normal and sham groups.After being compressed the myelinated nerve fibers became swollen,degenerated and broke down.The amount of myelinated nerve fibers in the normal group,the sham operation group and the three CSCI groups was (2771 ± 108),(2675 ± 199),(2403 ± 161),(1708 ± 70) and (8 10 ± 95) respectively.The amount of myelinated nerve fibers decreased in the CSCI groups and reached a minimum on the 7th day.The difference was statistically significant.The TEM quantity analysis showed that the G-ratios in the normal,sham operation,and CSCI 1 day,3 day and7 day groups were (18.10±0.4),(17.70±1.0),(6.69 ±0.8),(5.73 ±0.4) and (4.95 ±0.5) respectively.Compared with the normal and sham operation groups,the G-ratios in the 3 CSCI groups were lower and reached their minimum on the 7th day after injury.The difference was statistically significant.TEM observation showed that the axons and myelin sheaths were intact in the normal and sham groups.After CSCI the axons became swollen and cell organelles in the axoplasm degenerated and decreased.The layers of myelin sheath shrank,folded and even wrinkled,which had an onion-like appearance.The oligodendrocytes exhibited chromatin condensation.Macrophages showed infiltration.Western blotting showed that the expression of NG2 in the CSCI groups reached a maximum on the 1st day after injury and then decreased with time.The expression of NG2 in the CSCI groups was higher than in the normal and sham groups,and the difference was statistically significant.Conclusion Demyelination occurs after CSCI-the amount of myelinated nerve fibers decreases and neurological deficits increase with time.The expression of NG2 was associated with changes in the myelin sheaths after CSCI and contributed to recovery of the myelin sheath through proliferation and differentiation to oligodendrocytes and perhaps other kinds of cells.

Objective To evaluate the effect of sevoflurane anesthesia on the expression of hippocampal α4 subunit-containing nicotinic acetylcholine receptor (α4nAChR) in rats.Methods One hundred and forty-four Sprague-Dawley rats of both sexes,aged 3-4 months,weighing 220-270 g,were divided into 4 groups (n =36 each) using a random number table:control group (group C),sevoflurane anesthesia for 1 h group (group S1),sevoflurane anesthesia for 3 h group (group S2) and sevoflurane anesthesia for 5 h group (group S3).Group C inhaled air,and S1,S2 and S3 groups inhaled 3％ sevoflurane for 1,3 and 5 h,respectively.Twelve rats in each group were selected at 1 and 7 days after emergence from anesthesia to undergo spatial probe test.Rats were then sacrificed immediately after anesthesia and at 1 and 7 days after emergence from anesthesia,and hippocampi were removed for determination of the expression of α4nAchR protein and mRNA in hippocampal neurons (by Western blot or real-time polymerase chain reaction).Results Compared with group C,the duration of staying at the target quadrant was significantly shortened,and the ratio of duration of staying at the original platform quadrant to the total duration and ratio of swimming distance in the original platform quadrant to the total distance were decreased on 1 and 7 days after emergence from anesthesia,the expression of α4nAchR protein and mRNA was down-regulated,and the number of positive cells was reduced in S1,S2 and S3 groups (P＜0.05).Compared with S1 and S2 groups,the duration of staying at the target quadrant was significantly shortened,the ratio of duration of staying at the original platform quadrant to the total duration and ratio of swimming distance in the original platform quadrant to the total distance were decreased on 1 day after emergence from anesthesia in group S3 (P＜0.05).There was no significant difference in the expression of α4nAchR protein and mRNA or number of positive cells at each time point between group S1,group S2 and group S3 (P＞0.05).Conclusion The mechanism by which sevoflurane anesthesia induces cognitive dysfunction may be partially related to down-regulating the expression of hippocampal α4nAchR in rats.

ObjectiveTo observe the effect of Danshen injection （DAN） on platelet （PLT）-induced metastasis of breast cancer cells in vitro. MethodThe 3-（4，5-dimethylthiazol-2-yl）-2，5-diphenyltetrazolium bromide （MTT） assay was used to observe the effect of DAN on the growth of MDA-MB-231 cells in vitro. Oris™ migration assay was used to determine the effect of DAN （final mass concentrations 4， 8， 16 g·L^-1） on PLT （1.5×10¹⁰ cells/L）-induced migration of breast cancer cells in vitro. The effect of DAN on PLT-induced cell invasion was detected by Transwell assay. Immunofluorescence and Western blot were used to detect the effect of DAN on the protein expression associated with PLT-induced epithelial-mesenchymal transition （EMT）. In addition， enzyme-linked immune-sorbent assay （ELISA） was used to determine the effect of DAN （final mass concentrations 4， 8， 16， 32， 64 g·L^-1） on the secretion of transforming growth factor-β₁ （TGF-β₁）. Western blot was used to observe the effect of DAN on the expression of podoplanin （PDPN） protein in MDA-MB-231 cells induced by PLT. ResultCompared with the blank group， the DAN groups （32 and 64 g·L^-1） showed decreased A₅₇₀ （P<0.05， P<0.01）， and there was no significant difference in A₅₇₀ between DAN groups （4， 8， 16 g·L^-1）. Compared with the blank group， the PLT group showed increased cell migration and invasion， while DAN groups significantly inhibited PLT-induced cell migration and invasion. Compared with the blank group， the PLT group showed decreased expression of E-cadherin， while DAN could significantly reverse this effect of PLT. Compared with the blank group， the PLT group showed increased Slug and Snail protein expression （P<0.05， P<0.01）， while DAN significantly reversed Snail protein expression induced by PLT （P<0.05， P<0.01）. The content of TGF-β₁ in the PLT group increased （P<0.01）， while the secretion of TGF-β₁ induced by PLT decreased in the DAN groups （16， 32， and 64 g·L^-1） （P<0.05， P<0.01）， and the secretion of TGF-β₁ was not significantly affected in other DAN groups. PDPN protein expression in the PLT group increased （P<0.01）， while DAN could significantly inhibit PLT-induced PDPN expression （P<0.01）. ConclusionDAN can inhibit PLT-induced migration， invasion， and EMT of breast cancer cells. The mechanism may be related to the direct action between breast cancer cells and tumor cells by down-regulating PDPN expression and interfering with PLT and has nothing to do with the effect of TGF-β₁ secretion of PLT.

ObjectiveTo establish the categories and structure of physical activity in children with autism spectrum disorder (ASD), and systematically evaluate the long-term effect of physical activity on the executive function of children with ASD, based on the theoretical and methodological framework of the International Classification of Functioning, Disability, and Health-Children and Youth version (ICF-CY). MethodsA search was conducted in databases such as Wanfang data, CNKI, PubMed, Web of Science and ProQuest, to collect literatures about long-term physical activity for executive function of children with ASD published from 2014 to 2023. The literatures were reviewed based on inclusion and exclusion criteria, following PRISMA guidelines for systematic review, and the quality of the included literatures were assessed with the Physiotherapy Evidence Database (PEDro) scale. ResultsTotally, ten articles were included, consisting of nine randomized controlled trials (RCTs) and one non-randomized controlled trial, with a total of 351 children diagnosed as ASD, aged three to 18 years, came from Italy, Canada, South Korea, China and the United States, published mainly after 2016. Physical activity primarily included sports activities (such as baseball, basketball, table tennis and equine-assisted activities), skill-based activities (such as cycling, cognitive-motor training and active gaming), physical fitness activities (SPARK), as well as combat-related activities (martial arts and karate); 30 to 70 minutes a time (mainly 45 minutes), one to five times a week (mainly twice a week), for two to 24 weeks (mainly twelve weeks). Long-term physical activities had been found to improve inhibitory control and cognitive flexibility in children with ASD, although the effect on working memory was inconsistent. ConclusionLong-term physical activity may positively impact on executive function in children with ASD, especially inhibitory control and cognitive flexibility. However, the effect on working memory need more researches.