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Carrying out the training of critical thinking in pathophysiology teaching is appropriate, and the medical students critical thinking ability can be achieved via construction of the awareness, and diverse teaching methods which include questioning, exploration and discussion.
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As the expansion of classroom teaching,the emerging network-aided instruction could provid novel methods to improve pathophysiological teaching.With the methodological superiority of network and information technology,the network-aided pathophysiological teaching protocol should be well designed to attract learning interest and improve comprehensive abilities of the students.
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Objective To investigate the effect of geldanamycin(GA) on the expression of HSP(HSP90,HSP70,HSP27) and oncoprotein(mutant p53,CDK4) in human breast cancer cell line MDA-MB-435s.Methods Proliferation of MDA-MB-435s cells was measured with MTT assay.The mRNA expression levels of HSP90,HSP70 and HSP27 were detected by RT-PCR.The protein expression levels of HSP90,HSP70,HSP27,mutant p53 and CDK4 were detected by Western blot.Results GA inhibited the proliferation of MDA-MB-435s cells in a time-dose dependent manner.The expression level of mRNA and protein of HSP90,HSP70 and HSP27 were increased,and the increasing of HSP70 was the most significant,while the protein expression level of mutant p53 and CDK4 in MDA-MB-435s cells were reduced obviously after 48-hour treatment with 400 nmol/L GA as compared with that of control cells.Conclusion GA inhibits the proliferation of MDA-MB-435s cells by down-regulating the level of mutant p53 and CDK4 protein,and GA involves in the protection of cell stress through increasing the expression of HSP90,HSP70 and HSP27.
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AIM: To study the effects of (-)-epigallocatechin-3-gallate (EGCG), a tea extract, on the invasion and metastasis of breast cancer cell line MDA-MB-231 and the possible mechanisms in vitro. METHODS: The expression of MUC1 in breast cancer cells treated with or without EGCG was detected by immunohistochemistry. The effect of EGCG on invasion of MDA-MB-231 cells was evaluated using Transwell chambers attached with polycarbonate filters and reconstituted basement membrane (Matrigel). Gelatin zymography was performed to detect the secretion of collagenase-Ⅳ. RESULTS: EGCG reduced the expression of MUC1, significantly suppressed the invasion of tumor cells to basement membrane and reduced the secretion of collagenase-Ⅳ. CONCLUSION: In vitro, EGCG may suppress invasion, metastasis, and collagenase-Ⅳ secretion in MDA-MB-231 cells by inhibiting the production of MUC1.
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AIM:To explore the effect and significance of neuregulins /ErbB2 receptor signal transduction pathway on mtp53 and hypoxia-iducible factor-1?(HIF-1?) in none-overexpression ErbB2 breast cancer cell MDA-MB-231.METHODS:The expression of neuregulin was detected by immunocytochemistry and Western blotting.MDA-MB-231 cells were treated with ErbB2 kinase inhibitor AG825.Proliferation was measured by MTT assay.The cell cycle and apoptosis were determined by flow cytometry.The expressions of mtp53 and HIF-1? were detected by Western blotting.The mRNA expression of HIF-1? was detected by RT-PCR.RESULTS:MDA-MB-231 cells expressed a relative higher level of neuregulin.In the results of Western blotting,the positive reaction band was found in 44 kD which coincides with the molecular weight of neuregulin.When MDA-MB-231 cells were treated with AG825,the proliferation was inhibited in time and dose dependent manners(P
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Objective To investigate the correlation between the HSP90 expression and invasion and metastasis potential of human breast cancer cell line. Methods The mRNA expression level of HSP90 was detected by RT-PCR. The protein expression level of HSP90 was measured by Western blotting. The effects of HSP90 inhibitor Geldanamycin (GA) on the invasion and motility abilities of human breast cancer line MDA-MB-231 and MDA-MB-435s in vitro were explored by transwell chamber. Results The mRNA expression level of HSP90? in MDA-MB-435s cell was higher than that of MDA-MB-231 cell (P0.05) between the two cell lines. The protein expression level of HSP90 in MDA-MB-435s cell was higher than that of MDA-MB-231 cell (P0.05). After treated with GA, the invasive and metastatic potential in human breast cancer cell MDA-MB-435s and MDA-MB-231 was suppressed significantly (P
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Objective:To investigate the role of extracellular signal-regulated protein kinase(ERK) in estrogen-induced proliferation and cell cycle transformation of breast cancer cell line MCF-7 and the related mechanisms.Methods: Estrogen receptor-positive breast cancer cell line MCF-7 was used in our study.The effects of 17?-E2 on the proliferation of MCF-7 cells was investigated by MTT assay to determine the optimal concentration of 17?-E2 for the following experiment.The effect of PD98059 on 17?-E2-induced proliferation of MCF-7 cells was measured by MTT assay to determine the intermediate concentration of PD98059.The cell cycle was analyzed by flow cytometry and telomerase activity was determined by Telomerase repeat amplification protocol PCR(TRAP-PCR) silver staining.The expression of wild-type p53 and phosphorylated ERK1/2 protein was determined by Western blotting and the expression of wild-type p53 mRNA was detected by RT-PCR.Results: ERK phosphorylation inhibitor PD98059 inhibited the proliferation of MCF-7 cells treated with 17?-E2 in a time-and dose-dependent manner(P