丙戊酸钠对APP/PS1转基因小鼠自主活动及脑形态结构的影响

目的研究丙戊酸钠(valproic acid,VPA)对APP/PS1双转基因阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠自主活动及脑组织形态结构的影响,探讨VPA对AD的保护作用及可能机制。方法将3月龄APP/PS1双转基因小鼠及同窝野生型小鼠分为VPA处理组和生理盐水对照组,运用VPA[30 mg/(kg.d)]和等量生理盐水腹腔注射4周。旷场实验观察各组小鼠的自主活动能力;尼氏染色、透射电镜观察各组小鼠脑组织的病理改变。结果行为学结果显示:与野生型小鼠相比,AD模型小鼠自主活动明显减少(P<0.05);野生型小鼠VPA处理组与对照组自主活动无明显差异(P>0.05);而AD模型小鼠VPA处理组比对照组的自主活动明显减少(P<0.05)。尼氏染色显示:AD模型小鼠脑内神经元密度显著低于野生型小鼠。AD模型小鼠中,对照组脑内神经细胞明显肿胀,尼氏小体明显减少而致细胞质淡染,神经细胞密度降低(85.2±13.3);而VPA处理组脑内神经元肿胀程度明显减轻,神经元数量显著回升(116.9±16.2,P<0.05),但VPA不影响野生型小鼠脑内的神经元数量及形态(VPA处理组:142.2±24.4 vs生理盐水对照组:136.7±23.1,P>0.05)。电镜结果显示AD模型小鼠对照组脑内神经元细胞核、线粒体及神经毡肿胀明显,突触结构稀松;而AD模型小鼠VPA处理组脑内神经元细胞核、线粒体及神经毡的水肿明显减轻,突触结构清晰。结论 VPA可显著减少APP/PS1双转基因AD模型小鼠的自主行为,显著减轻躁狂症状;VPA可改善APP/PS1双转基因小鼠脑内神经细胞的形态结构,减少肿胀的神经元并抑制神经元数量的减少。     

脑红蛋白在内毒素脑损伤大鼠模型中的表达变化

Objective To investigate the expression of neuroglobin(Ngb) in frontal cortex, cere-brospinal fluid (CSF) and serum in rats with brain injury induced by LPS and to elucidate its significance. Methods Seventy adult Sprague-Dawley rats were randomly divided into LPS (n = 60, with injection of 0.1 mg/kg LPS into cistern) and control (C, n =10, with injection of equal volume of isotonic saline into cistern) groups, with 10 rats in each group. The plasma, CSF as well as frontal cortex from sacrificed rats were collected in LPS group at 3, 6, 12, 24, 48, 72 post injection hour (PIH), with 10 rats at each time point. The protein expression of Ngb was measured by enzyme-linked immunosorbent assay(ELISA) and Western blot. Expression of Ngb in frontal cortex was determined by SP. Water content of frontal cortex was assessed by drying method. The correlation among Ngb contents in serum, CSF, frontal cortex and water con-tent of frontal cortex was analyzed with multiple comparison. Results Ngb expression ( by ELISA) : Ngb expression of frontal cortex, CSF, and serum in LPS group was higher than that in C group at each time point, and it peaked at 48 PBH (35.4±3.9, 22.7±3.1, 14.4±2.8 ng/mL, respectively, P <0.01). Ngb ex-pression ( by Western blot) : Ngb protein with relative molecular mass of 17×103 was observed in each group. Ngb expression detected by Western blot was similar to that detected by ELISA. Brain water content was significantly greater in LPS group than that of C group at 6-72 PIH ( P<0.01) , and it peaked at 48 PBH ( 83.3±1.9) %. Ngb contents in serum, CSF, frontal cortex, and water content of frontal cortex were positively correlated with muhipie comparison (γ=0.631-0.719, P<0.01). Conclusions Up-regu-lation of Ngb expression in brain injury induced by LPS is correlated with duration after challenge of LPS.     

甘草素通过抗炎发挥对阿尔茨海默病的保护作用

目的研究植物雌激素甘草素(liquiritigenin,LG)是否通过抗炎对阿尔茨海默病(Alzheimer’s disease,AD)发挥保护作用。方法 LG是从中药甘草中提取的一种黄酮类化合物单体,具有多靶向作用,如抗炎、抗氧化等。本实验用N2A细胞(神经瘤母细胞)作为正常对照细胞和稳定表达瑞士突变型淀粉样蛋白前体蛋白(amyloid precursor protein,APP)的N2A细胞(N2AAPP)作为AD细胞模型,结合LG处理,通过MTT、ELISA、Western blot、RT-PCR检测LG对AD模型细胞的细胞活性、雌激素受体(ERβ)、炎症相关蛋白NLRP3和caspase-1以及炎症因子IL-1β、TNF-α的影响。结果与正常的N2A细胞相比,N2A-APP细胞中APP、BACE1蛋白表达以及Aβ水平显著增加,说明N2A-APP作为AD模型细胞的有效性。MTT结果显示LG不影响N2A的细胞活力(P0.05)。Westers blot结果显示,与正常N2A细胞相比,N2A-APP细胞内ERβ的表达显著下调,而LG处理可显著逆转ERβ的表达。Westers blot结果还发现,与正常细胞相比,N2A-APP细胞内炎症相关蛋白NLRP3和p-caspase-1蛋白表达显著增强,而LG处理可有效逆转NLRP3和p-caspase-1的表达上调(P0.01)。相应地,RT-PCR结果发现,LG可显著降低N2A-APP细胞内炎症因子IL-1β、TNF-α的水平。结论甘草素可有效抑制AD模型细胞的炎症反应,其机制可能与其上调ERβ蛋白的表达有关。     

转录因子AP-2α对脑外伤后蓝斑神经元TH表达的影响

目的 探讨转录因子激动蛋白-2α(activator protein 2α, AP-2α)对脑外伤后蓝斑去甲肾上腺素能神经元中酪氨酸羟化酶(tyrosine hydroxylase, TH)表达的影响.方法 将90只Wistar大鼠分为对照组和脑外伤组,脑外伤组又分为外伤后1、3、6、24、72 h共5个组(n=15).用Feeney氏法制作机械性脑外伤大鼠模型,分别于脑外伤后各相应时间点取出脑干,对蓝斑(locus ceruleus, LC)所在部位作冷冻切片,用免疫荧光双标检测TH和AP-2的表达,观察二者在外伤后各相应时间点LC神经元中的表达变化.结果 在脑外伤后各时段,LC神经元的TH和AP-2α 阳性细胞数量和荧光强度值均比对照组明显增加(P《0.05),3 h达到高峰,随后逐渐降低,但72 h仍然高于对照组;而且TH和AP-2α的表达变化趋势基本一致,在同一神经元可以共表达.结论 机械性脑外伤使LC去甲肾上腺素能神经元中TH表达增加,使去甲肾上腺素(norepinephrine, NE)合成增多,NE在外伤应激过程中起着重要作用;AP-2α参与了TH的表达调控,AP-2α上调可能是导致了TH表达增加的重要原因.     

生命视角下人体解剖学课程思政教学与实践体系的构建及拓展

<正>习近平总书记在全国高校思想政治工作会议上指出,“要坚持把立德树人作为中心环节,把思想政治工作贯穿教育教学全过程,实现全程育人、全方位育人,努力开创我国高等教育事业发展新局面”^[1]。在这一宏大的历史背景下,医学专业教师落实“课程思政”对大学生“价值引领”的举措很多,在教学内容、教学方法、教学评价等角度都有涉猎[2-4]),形式多样而效果欠佳,原因在于未能找准育人角度。     

半胱氨酸蛋白酶-12表达与细胞色素C释放在脊髓压迫性损伤后少突胶质细胞凋亡中的作用

目的：探讨半胱氨酸蛋白酶-12（Caspase-12）表达与细胞色素C（cytochrome-C,Cyto-C）释放在脊髓压迫性损伤（com－pressed spinal cord injury,CSCI）后少突胶质细胞凋亡中的作用。方法：采用自行设计的方法制作脊髓压迫模型,通过原位细胞凋亡染色于压迫后1、3、7 d检测CSCI后少突胶质细胞凋亡;运用Western blot技术从分子水平分别检测与细胞凋亡有关的Caspase-12和Cyto-C的表达。结果：不同组别凋亡的少突胶质细胞数目不全相同（F=30.946,P=0.000）,LSD-t法两两比较,1、3、7 d模型组凋亡的少突胶质细胞数目均高于正常组（P=0.000）。与对照组、1 d组、3 d组相比,7 d组凋亡的少突胶质细胞数目最多,组间比较,差异有统计学意义（P=0.000）。不同组别Caspase-12和Cyto-C蛋白表达不全相同（F分别等于1 402.646和326.638,P=0.000）,LSD-t法两两比较,1、3、7 d模型组的Caspase-12和Cyto-C蛋白表达均高于正常组（P=0.000）,与对照组、1 d组、3 d组相比,7 d组的Caspase-12和Cyto-C蛋白表达水平均最高,组间比较,差异有统计学意义（P=0.000）。结论：CSCI后出现了少突胶质细胞凋亡,其凋亡机制可能与Caspase-12表达增强及Cyto-C释放共同作用有关。     

脑红蛋白在内毒素脑损伤大鼠模型中的表达变化

Objective To investigate the expression of neuroglobin(Ngb) in frontal cortex, cere-brospinal fluid (CSF) and serum in rats with brain injury induced by LPS and to elucidate its significance. Methods Seventy adult Sprague-Dawley rats were randomly divided into LPS (n = 60, with injection of 0.1 mg/kg LPS into cistern) and control (C, n =10, with injection of equal volume of isotonic saline into cistern) groups, with 10 rats in each group. The plasma, CSF as well as frontal cortex from sacrificed rats were collected in LPS group at 3, 6, 12, 24, 48, 72 post injection hour (PIH), with 10 rats at each time point. The protein expression of Ngb was measured by enzyme-linked immunosorbent assay(ELISA) and Western blot. Expression of Ngb in frontal cortex was determined by SP. Water content of frontal cortex was assessed by drying method. The correlation among Ngb contents in serum, CSF, frontal cortex and water con-tent of frontal cortex was analyzed with multiple comparison. Results Ngb expression ( by ELISA) : Ngb expression of frontal cortex, CSF, and serum in LPS group was higher than that in C group at each time point, and it peaked at 48 PBH (35.4±3.9, 22.7±3.1, 14.4±2.8 ng/mL, respectively, P <0.01). Ngb ex-pression ( by Western blot) : Ngb protein with relative molecular mass of 17×103 was observed in each group. Ngb expression detected by Western blot was similar to that detected by ELISA. Brain water content was significantly greater in LPS group than that of C group at 6-72 PIH ( P<0.01) , and it peaked at 48 PBH ( 83.3±1.9) %. Ngb contents in serum, CSF, frontal cortex, and water content of frontal cortex were positively correlated with muhipie comparison (γ=0.631-0.719, P<0.01). Conclusions Up-regu-lation of Ngb expression in brain injury induced by LPS is correlated with duration after challenge of LPS.     

慢性脑缺血模型小鼠视网膜内血管内皮生长因子和胶质纤维酸性蛋白的表达变化

目的：探讨血管内皮生长因子（vascular endothelial growth factor,VEGF）和胶质纤维酸性蛋白（glial fibrillary acidic pro－tein,GFAP）在慢性脑缺血模型小鼠视网膜内的表达规律及两者的关系。方法：采用C57小鼠建立慢性脑缺血模型,结合免疫组化方法,观察缺血不同时间段小鼠视网膜中 VEGF、GFAP在时间和空间上的表达变化。结果：在假手术组中 VEGF、GFAP呈弱表达或不表达;在手术组中,缺血120 d时 VEGF、GFAP表达增加（P=0.002,P=0.006）,随缺血时间的延长,缺血180 d时 VEGF、GFAP表达强度及空间分布范围呈进行性增加（P=0.050,P=0.000）。结论：VEGF、GFAP在慢性脑缺血模型小鼠视网膜中表达进行性上调,提示两者参与了视网膜缺血损伤的病理改变过程,并在视网膜缺血损伤机制中起着重要作用。     

“以器官系统为中心，基础与临床全线整合”教学模式解剖学知识点整合的实践与思考

正回顾高等医学教育课程模式,20世纪50年代"以器官系统为中心"的课程模式问世;90年代,美国医学院校协会在全国推行"医学院校培养目标研究项目",许多院校实行了以器官系统为中心的课程、以问题为导向的课程、以社区为基础的课程等整合课程,成为第2次医学教育改革,对