OBJECTIVE To establish an in vitro blood-cerebrospinal fluid barrier (BCB) model to investigate the underlying mechanism of lead-induced BCB injuries.METHODS The in vitro BCB model was established by Z310 cells.Different concentrations of Pb(AC)2 (2.5,5.0 and 10.0 mmol·L-1) were used for 24,48 and 72 h.Transendothelial electrical resistance (TEER) and flux of FITC-dextran were performed to determine the permeability of the in vitro BCB model.Western blotting and immunofluorescence methods were used to observe the expression of tight junction protein ZO-1 and occludin.RESULTS Compared with control group,Pb(AC)2 2.5,5.0 and 10.0 mmol· L-1 exposure for 48 h to Z310 cells had no significant effect on survival rate and density.TEER in different groups was gradually increasing.At the 12th day after Pb(AC)2 exposure,the values of TEER and flux of FITC-dextran in Pb(AC)2 5 and 10 mmol· L-1 groups were significantly decreased (P＜0.05).Western blotting and immunofluorescence images showed that the expression of ZO-1 and occludin were significantly decreased (P＜0.05) after Pb(AC)2 exposure for 48 h.CONCLUSION Lead exposure can cause the breakdown of BCB barriers,and this effect may be mediated by reducing the expression of ZO-1 and occludin proteins.

Objective:To evaluate the effects of Sander Ⅱ appliance in the orthodontic treatment of adolescent ClassⅡmalocclusion. Methods:15 cases (6 male and 9 female)of adolescent ClassⅡ malocclusion with mandibular retrution were treated with Sander Ⅱappliance.Pre-treatment and post-treatment Lateral cephalogram measurements were traced and analyzed in terms of 28 indicators. SPSS 19.0 software package was used for paired t test.Results:After treatment,15 patients achieved remarkable improvement in the maxillofacial profile and normal overjet of teeth.The cephalometric analysis showed that ANB,OJ,H°and U1-E decreased(P <0. 05),SNB,B-OLP,Pg-OLP(mm),Ii-OLP,Ms-OLP(mm),Mi-OLP(mm),N-Me,ANS-Me,S-Go,Go-Gn,N'-Pg'/FH,Cm-Sn-Ls and Pg-Pg'increased(P <0.05).There was no significant change in SN-MP,SN-OL and Y-axis before and after treatment. Conclusion:Sander Ⅱ appliance is effective in the treatment of adolescent early Class Ⅱmalocclusion.

Objective This study aimed to investigate the effects of P.odoratum extract on lactase activity and microflora diversity in mice with bacterial dysbacteriosis.Methods SPF male BALB/c mice were randomized into 4 groups:control,model,P.odoratum extract low dose(1.56 g·kg-1·d-1)and high dose(3.12 g·kg-1·d-1)treatment group.There were 8 mice in each group(5 in the blank group).In addition to the control group,after 7 days of intragastric administration of mixed antibiotics,the administration groups were given P.odoratum extract for 7 days,and the control group and the model group were given the same amount of sterile water.The changes of diarrhea,body weight and food intake of mice were recorded.The colon HE staining sections,ZO-1 protein,IL-6 expression,and serum LPS concentration were detected.Feces were collected for lactase activity and microbial diversity determination with 16S rRNA high-throughput sequencing technology.Results After 7 days of antibiotic intervention,compared with the control group,the mice in the model group had soft stool,weight loss,reduced food intake,and significantly reduced intestinal flora diversity.At the 14th day,in the model group,ulceration accompanied by slight interstitial congestion and edema was seen in the colon,ZO-1 expression was significantly reduced,IL-6 expression was significantly increased,serum LPS was significantly increased,lactase activity was significantly reduced,and intestinal flora diversity was still lower compared with the control group.After 7 days of administration,compared with the model group,P.odoratum reduced the diarrhea rate of mice,promoted a recovery of body weight and food intake,downregulated pathological colon tissue damage,significantly increased ZO-1 protein expression,and reduced colon factor IL-6 and serum LPS concentration.In addition,P.odoratum can significantly up-regulate lactase activity and improve the community richness and diversity of dysbacteriosis mice.It is shown that three phyla(up-regulated Firmicutes,down-regulated Proteobacteria and Bacteroidetes)and seven genera(up-regulated Rikenellaceae_RC9_gut_group,Rikenella,Colidextribacter,norank_f__Lachnospiraceae,norank_f__Oscillospiraceae,and Lachnospiraceae_NK4A136_group,down-regulated Alloprevotella),the abundance of which was significantly correlated with body weight and lactase activity,serum LPS,and colon factor IL-6.Conclusion P.odoratum can alleviate the gut barrier injury and dysfunction caused by antibiotic induced dysbiosis,and its mechanism may be achieved by regulating microflora structure.