Objective To establish an electrical field(EF)stimulation model for Schwann cells(SCs),and to provide a basis for exploring the mechanisms of EF stimulation in promoting proliferation,migration and epithelial-to-mesenchymal transition of SCs.Methods A YC-3 bipolar programmable electrical stimulator and an electrotaxis chamber were used to construct an EF stimulation system to stimulate SCs.In the study,SCs were divided into control group(Ctrl)receiving no EF stimulation and EF group stimulated by continuous constant-voltage EF(100 mV/mm,3 h).The effects of EF stimulation on the proliferation and migration of SCs were analyzed using CCK-8 assay,and wound healing assay+Transwell assay,separately;and its effect on SCs adhesion was observed by analyzing the expressions of E-cadherin and N-cadherin using Western Blot.Results The CCK-8 assay results suggested that the absorbance at 450 nm was significantly higher in EF group than in Ctrl group(P<0.05).The results of wound healing assay+Transwell assay revealed that EF group had higher cell migration efficiency than Ctrl group(P<0.05).Western Blot results showed decreased E-cadherin expression and increased N-cadherin expression in EF group as compared with Ctrl group(P<0.05).Conclusion The improved EF stimulation system for SCs is operable.EF stimulation can promote the proliferation and migration of SCs.The decreased E-cadherin expression and increased N-cadherin expression may be related to the occurrence of epithelial-to-mesenchymal transition in SCs after EF stimulation.

Objective To establish an electrical field(EF)stimulation model for Schwann cells(SCs),and to provide a basis for exploring the mechanisms of EF stimulation in promoting proliferation,migration and epithelial-to-mesenchymal transition of SCs.Methods A YC-3 bipolar programmable electrical stimulator and an electrotaxis chamber were used to construct an EF stimulation system to stimulate SCs.In the study,SCs were divided into control group(Ctrl)receiving no EF stimulation and EF group stimulated by continuous constant-voltage EF(100 mV/mm,3 h).The effects of EF stimulation on the proliferation and migration of SCs were analyzed using CCK-8 assay,and wound healing assay+Transwell assay,separately;and its effect on SCs adhesion was observed by analyzing the expressions of E-cadherin and N-cadherin using Western Blot.Results The CCK-8 assay results suggested that the absorbance at 450 nm was significantly higher in EF group than in Ctrl group(P<0.05).The results of wound healing assay+Transwell assay revealed that EF group had higher cell migration efficiency than Ctrl group(P<0.05).Western Blot results showed decreased E-cadherin expression and increased N-cadherin expression in EF group as compared with Ctrl group(P<0.05).Conclusion The improved EF stimulation system for SCs is operable.EF stimulation can promote the proliferation and migration of SCs.The decreased E-cadherin expression and increased N-cadherin expression may be related to the occurrence of epithelial-to-mesenchymal transition in SCs after EF stimulation.

Objective To investigate the retention level and its influencing factors for male nurses,and explore effective strategies to increase retention level of male nurses.Methods A sample of 610 male nurses from many hospitals in Tianjin were investigated with the self-designed demographic questionnaire,Retention Scale and Perceived Organization Support.The results underwent analysis.Results Male nurses' retention score was (20.71±4.00) points.Single factor analysis found that marriage,age,number of children,time engaged in nursing work,the working years in present position,the purpose of the work had statistically significant influence on retention scores of the male nurses.Multiple linear regression analysis showed that marriage,professional and technical titles,the purpose of work,work support and value identification were the predictive effect on the degree of the retention.Conclusions The retention of male nurses in Tianjin was in the medium level.Hospitals and all relevant departments should take effective measures,improve the professional sense of worth of the male nurses and job satisfaction,in order to enhance the man nurses' retention rate,promote the sustainable development of the nursing team construction.

BACKGROUND: Hippocampal formation of brain, a cerebral area related with learning and memory, is closely related to spatial cognitive activity.Peroxidative stress following the onset of cerebral ischemia can induce DNA injury in hippocampal 'area and dentate gyrus, the fall of the ability of DNA plerosis and correspondingly a decline in the function of learning and memory.OBJECTIVE: To investigate the effect of hongjingtian on the expression of nucleic acid of hippocampal area and dentate gyrus, the learning and memory area of rats with complete cerebral ischemia-reperfusion injury.DESIGN: Randomized controlled study.SETTING: Central Laboratory of Armed Police Medical College.PARTICIPANTS: The experiment was completed at the Central Laboratory of Armed Police Medical College from April 2002 to April 2004. Totally 60 Wistar male rats were selected and divided randomly into 5 groups Model group: Rats were perfused daily with distilled water of a volume the perfused daily with distilled water of a volume the same as that in medication group.METHODS: Rats in each group were perfused incessantly for 7 days.Modified Pulsinelli-4 vessel blocking method was used to reproduce the rat model of acute complete cerebral ischemia-reperfusion. Rats in sham-operation group were not treated with the operation of burning vertebral artery and clipping common carotid artery. The changes of DNA and RNA expressions in cerebral hippocampal area and dentate gyrus were observed with acridine orange staining method after model establishment.MAIN OUTCOME MEASURES: Expression of DNA and RNA in cerebral hippocampal area and dentate gyrus of rats in each group.RESULTS: All 60 rats entered the final analysis. DNA and RNA in shamoperation group distributed evenly, border of fluorescent reflex was legible and response intensity was strong. Border of DNA and RNA fluorescent reflex was illegible and response intensity was obviously weak in model ly, border of fluorescent reflex was legible and response intensity was group was not of obvious difference as compared with that in model group.CONCLUSION: The illegibility of DNA and RNA fluorescent response in operation group is related with the breakage of DNA chain induced by oxidative stress during cerebral ischemia-reperfusion injury. Border of DNA and RNA fluorescent reflex in hippocampal area and dentate gyrus is legihibit the breakage of DNA chain induced by oxidative stress and protect learning and memory function in hippocampal area and dentate gyrus of rats with complete cerebral ischemia-reperfusion.