紫杉醇脂质体对乳腺癌细胞SK-BR-3的放疗增敏作用及其机制

目的探索紫杉醇脂质体(力扑素)对乳腺癌细胞株SK-BR-3是否具有放疗增敏作用及其放疗增敏机制。方法利用MTT法检测放疗组、单药紫杉醇脂质体(以下简称单药组)及紫杉醇脂质体联合放疗(以下简称联合组)在不同时间对乳腺癌细胞SK-BR-3的生长抑制作用。利用流式细胞仪检测放疗组、单药组及联合组对细胞周期及凋亡的影响。利用Western blot检测凋亡相关蛋白Caspase-3、Bcl-2及Bax在不同处理组中的表达,探索紫杉醇脂质体放疗增敏作用的机制。结果 MTT结果显示放疗组、单药组及联合组均具有细胞生长抑制作用,与细胞对照组相比差异具有统计学意义(P<0.05),而且联合组较单药及放疗组具有更显著的细胞生长抑制作用,差异具有统计学意义(P<0.05);细胞凋亡结果显示放疗组、单药组及联合组凋亡细胞均明显增加,与对照组相比差异具有统计学意义(P<0.05),并且联合组在细胞周期中均出现了明显的凋亡峰;Western blot结果显示,促凋亡蛋白Caspase-3和Bax的表达在放疗组、单药组和联合组中均升高,与对照组相比差异具有统计学意义(P<0.05),并且联合组升高较放疗组及单药组更为显著,差异具有统计学意义(P<0.05),而抗凋亡蛋白Bcl-2的表达在放疗组、单药组及联合组均减低,与对照组相比差异具有统计学意义(P<0.05),而联合组较放疗组及单药组降低更明显,差异具有统计学意义(P<0.05)。结论紫杉醇脂质体具有明显的放疗增敏作用,并且可能通过调控凋亡相关蛋白的表达引起细胞凋亡来发挥其放疗增敏作用。

紫杉醇脂质体与培美曲塞在乳腺癌细胞SK-BR-3中放疗增敏作用的比较及其机制

目的:比较紫杉醇脂质体(力扑素)与培美曲塞在乳腺癌细胞SK-BR-3中的放疗增敏作用,探索两者放疗增敏作用的机制。方法:分组设置为细胞对照组、放疗组、力扑素+放疗组、培美曲塞+放疗组。MTT法检测不同处理组细胞生长抑制率,流式细胞仪检测不同处理组细胞周期及凋亡率,Western blot检测不同处理组凋亡相关蛋白Caspase-3、Bcl-2及Bax的表达。结果:MTT结果显示,力扑素+放疗能够发挥比培美曲塞+放疗更明显的细胞生长抑制作用,两者相比有统计学差异(P<0.05);流式检测结果显示,力扑素+放疗能够引起更明显的细胞凋亡,与培美曲塞+放疗相比有统计学差异(P<0.05),同样力扑素+放疗在细胞周期中能够诱导产生更明显的亚G1峰,与培美曲塞+放疗相比有统计学差异(P<0.05);Western blot结果显示,促凋亡蛋白Caspase-3和Bax的表达在不同处理组中均升高,但力扑素+放疗组升高更显著,与培美曲塞+放疗相比有统计学差异(P<0.05),而抗凋亡蛋白Bcl-2的表达在不同处理组中均降低,但力扑素+放疗比培美曲塞+放疗降低更明显,有统计学差异(P<0.05)。结论:力扑素比培美曲塞具有更强的放疗增敏作用,并且可能是通过调控凋亡蛋白的表达来发挥其放疗增敏作用的。

miR-17-92基因簇反义寡核苷酸对胃癌细胞增殖与侵袭的抑制作用

目的:探讨miR-17-92基因簇反义寡核苷酸对人胃癌细胞株SGC-7901的增殖及侵袭的影响。方法:合成miR-17-92基因簇中miR-17、miR-18a、miR-20a的反义寡核苷酸,通过实时荧光定量PCR验证miR-17、miR-18a、miR-20a反义寡核苷酸对SGC-7901细胞的miR-17、miR-18a、miR-20a的抑制效果,然后利用MTT、Transwell检测抑制表达后对细胞增殖及侵袭的影响。结果:miR-17、miR-18a、miR-20a的反义寡核苷酸能够抑制对应miRNA的表达,同时抑制了胃癌细胞的增殖与侵袭。结论:miR-17-92基因簇可能在胃癌发生发展中起到了癌基因的作用。

Phospholipase A_2 changes and its significance on brain tissue of rat in severe acute pancreatitis

Objective To survey changes and the significance of phospholipase A_2(PLA_2) on brain tissue of SD rat in acute pancreatitis.Methods With retrograde injection of 3% taurocholate sodium into pancreatic and biliary duct,rat model of severe acute pancreatitis(SAP) was made,and it included four groups: the control group,the sham-operation group, the SAP group and the PLA_2 inhibitor-treated group of SAP.Serum amylases,PLA_2 and PLA_2 in brain tissue were measured and the brain tissue changes were observed.Results There were no significant difference in serum amylases, PLA_2 and PLA_2 in brain tissue between the sham-operation and the control groups;the levels of serum amylases,PLA_2 and PLA_2 in brain tissue in the SAP group were higher than those in the control.In the SAP group expansion and hemorrhage of meninges,intracephalic arteriolar hyperemia,in meninges and cephalic-parenchyma infiltration of inflammatory cells and interval broaden were observed,significant differences were found between two groups.Compared with the SAP group,the level of serum amylase,PLA_2 and PLA_2 in brain tissue were reduced significantly in the treatment group of SAP.Pathological damages in the treatment group were significantly reduced when compared with the SAP group.Conclusion PLA_2 might play an important role in brain tissue damages in severe acute pancreatitis.

如何有效贯彻“六步教学法”

“六步教学法”是在新课改思想的指导下,以学科导学案为载体,以学生自主学习为手段,化学生的传统被动式学习为主动学习,更新教师的教育观念,改变陈旧的教学模式,树立高效教学观,体现学生的主体地位,提高教育教学质量。“六步”即“示、看、动、练、评、总”。“示”——创设情境,出示教学目标;“看”——让学生带着问题自主学习;“动”——生生互动,师生互动;“练”——当堂训练,难易结合,检验学习效果;“评”——当堂训练,师生给予评价;“总”——对所学内容进行总结,形成完整的知识体系,明确重点、难点。