ABSTRACT
Objective:To explore the application and effect of team-based learning (TBL) combined with flipped classroom in the teaching of physiology.Methods:A total of 70 medical students were selected and randomly divided into two groups, experimental group ( n=34) and control group ( n=36). Both groups studied digestion physiology by different method. In the experimental group, the students were taught by TBL combined with flipped classroom. The control group was given traditional teaching. The students studied and discussed problems in a team, and shared the answers in the flipped classroom. The effects of teaching were evaluated by the final test scores and the self-made questionnaire. SPSS 17.0 was used for t test on data comparison between the two groups. Results:The test scores of digestion physiology in the experimental group were (5.47±1.02) points, which were significantly higher than those of the control group (4.42±1.63) points, with significant differences ( P=0.020). A total of 34 questionnaires were issued and 34 valid questionnaires were collected, with an effective rate of 100%. The questionnaire results showed that TBL combined with flipped classroom was accepted and approved by about 82% of students in the experimental group who agreed that the teaching model helps enhance students' initiative and interest in learning, develop their sense of cooperation and comprehensive application ability. Conclusion:TBL combined with flipped classroom is feasible and effective in the physiological teaching, and it can be popularized in medical courses.
ABSTRACT
Objective To evaluate the effects and underlying mechanisms of crocin on glutamate-induced apoptosis of retinal ganglion cells (RGCs) by affecting extracellular calcium influx.Methods Primary rat retinal ganglion cells were isolated and stimulated with glutamate at concentrations of 0.1 mmol/L and 1 mmol/L for 24 h or 48 h,respectively,to establish apoptosis model of RGCs.Afterwards,crocin of different doses (0.1,1.0 and 3.0 μmol/L) was used to treat the glutamate-induced RGCs for 12 h;then cell apoptosis was detected by Annexin V-FITC/PI staining.The intracellular calcium concentration was determined by FIuo-3/AM fluorescent labeling.Western blot was used to examine the effect of crocin on Ca2+-mediated apoptotic signal molecules calpain and CaMKII.The mitochondrial membrane potential was detected by JC-1 staining and mitochondrial apoptosis-related signaling molecules Caspase-3,Caspase-9 and Bcl-2/Bax were evaluated by Western blot,respectively.Results In comparison with the untreated controls,the cell apoptosis of RGCs exposed to 0.1 mmol/L of glutamate for 24 h did not significantly change (P＞ 0.05).However,apoptosis rate of the cells reached (43.050 ± 2.616) ％ when the stimulation time lasted for 48 h and showed a significant increase (P＜0.01).Treatment with higher-dose glutamate (1 mmol/L) significantly increased apoptosis of RGCs at 24 h (46.450±1.061)％ and 48 h (45.500±3.253)％ compared with the controls (P＜0.01).RGCs were induced by 1 mmol/L of glutamate for 12 h,followed by the treatment with crocin at concentrations of 0.1,1.0 and 3.0 μmol/L,respectively.Each dose of crocin could significantly inhibit cell apoptosis in the dose-dependent manner (P＜0.01).In addition,crocin at 1.0 μmol/L blocked glutamate-induced extracellular calcium influx,inhibited the expression of calcium-dependent proteins Calpainl and CaMK Ⅱ.Moreover,crocin at the dose of 1.0 μmol/L also increased mitochondrial membrane potential,suppressed the expressions of Caspase-3 and Caspase-9,and elevated Bcl-2/Bax ratio.Cornclusion Crocin inhibits glutamate-induced apoptosis of retinal ganglion cells through suppressing extracellular calcium influx,thereby blocking calcium-dependent and mitochondria-dependent apoptosis signaling pathways.