Application of PBL combined with CBL and CP teaching methods in standardized residency training in the department of hepatobiliary surgery / 中华医学教育探索杂志

Objective:To analyze the effect of problem-based learning (PBL) combined with case-based learning (CBL) and clinical pathway (CP) teaching methods in standardized residency training in department of hepatobiliary surgery.Methods:A total of 64 residents who received the standardized residency training in the Department of Hepatobiliary Surgery in Shaanxi Provincial People's Hospital from July 2018 to July 2019 were selected and divided into the observation group and the control group. The control group used PBL + CBL teaching methods, while the observation group adopted PBL + CBL + CP teaching methods. The after-department examination scores and the teaching cognition scores of the two groups were compared. SPSS 15.0 was used for t-test and Chi-square test. Results:The after-department examination scores of the two groups were compared. Compared with the control group, the examination scores of professional theories, case analysis and operation skills in the observation group were significantly higher, and the difference was statistically significant ( t = 6.98, 7.85, 7.01, P < 0.05). In terms of recognition of teaching, the observation group was significantly higher than the control group, and the difference was statistically significant ( t = 9.14, P < 0.05). Conclusion:The PBL + CBL + CP teaching is conducive to the comprehensive and systematic mastery of knowledge and the rapid establishment of scientific clinical thinking. It has a strong scientific and systematic nature and is worthy of promotion.

Cisplatin induces cell cycle arrest and senescence via upregulating P53 and P21 expression in HepG2 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>Cellular senescence as one of the important steps against tumor is observed in many cancer patients receiving chemotherapy and is related to chemotherapeutic response. To investigate the effect of cisplatin on hepatocellular carcinoma, we treated HepG2 cells exhibiting wild-type TP53 with gradient concentrations of cisplatin.</p><p><b>METHODS</b>The inhibitory effects of cisplatin on human hepatoma HepG2 cells were detected by MTT assay and colony formation test. The changes in cell cycle were analyzed by flow cytometry, and cellular senescence was detected with senescence associated β-galactosidase (SA β-gal) staining. The relative mRNA expression levels of TP53, P21 and P19 was estimated using semi-quantitative real-time RT-PCR, and the protein expressions of P53 and P21 were detected using Western blotting.</p><p><b>RESULTS</b>Cisplatin induced irreversible proliferation inhibition and G1 phase arrest of HepG2 cells. Elevated levels of senescence-associated β-galactosidase was observed in HepG2 cells exposed to low doses of cisplatin. P19 expression immediately increased following cisplatin exposure and reached the maximum level at 48 h, followed then by a rapid decrease to the baseline level, whereas the expressions levels of TP53 and P21 mRNA increased continuously. Western blotting confirmed P53 and P21 expression changes similar to their mRNA expressions during cisplatin-induced cellular senescence in HepG2 cells.</p><p><b>CONCLUSION</b>Our results revealed a functional link between cisplatin and hepatocellular senescence. Cellular senescence induced by cisplatin as a stabile senescent cellular model can be used for further research.</p>