Bcl-2家族参与β-淀粉样蛋白对PC12细胞的致凋亡作用

目的：研究bcl一2家族(主要是bcl-xl和bax)基因及相关蛋白是否参与水溶性淀粉样蛋白对培养的大鼠嗜铬细胞瘤细胞的毒性作用。方法：应用电镜和DNA电泳判断细胞损伤途径，应用RT-PCR，免疫细胞化学和免疫印迹判断bcl-2家族及其相关蛋白是否参与淀粉样蛋白的损伤作用。结果：10μmol／LAβ25-35作用24h后，电镜和DNA电泳均显示Aβ25-35可以导致PCI2细胞凋亡；RT-PCR表明药物作用后6h，bcl-xl mRNA表达量减少而bax mRNA表达量增加；免疫印迹和免疫细胞化学结果显示药物作用后24h，Bax蛋白增加而Bcl-xl无明显改变。结论：水溶性淀粉样蛋白可以导致神经细胞凋亡，bcl-2家族参与了作用环节，对阿尔茨海默病的发病起着重要的作用。     

FoxM1抑制剂硫链丝菌素对髓母细胞瘤Daoy细胞增殖与凋亡的影响

目的 探讨FoxM1抑制剂硫链丝菌素对髓母细胞瘤Daoy细胞株增殖及凋亡的影响. 方法 体外常规培养髓母细胞瘤Daoy细胞株,CCK-8法检测0、1、1.5、2、3、5μmol/L硫链丝菌素作用24、48、72 h后细胞存活率的变化;实时定量聚合酶链反应(RT-PCR)、免疫印迹法分别检测0、1、1.5、2μmol/L硫链丝菌素作用48 h后细胞FxoMl mRNA和蛋白的表达,流式细胞仪检测细胞周期和凋亡,免疫印迹法检测凋亡相关蛋白Bcl-2、Bax的表达. 结果 CCK-8检测显示不同浓度硫链丝菌素作用后Doay细胞存活率下降,且呈浓度和时间依赖性,差异有统计学意义(P＜0.05).24、48、72 h的IC50分别为(2.1±0.15)、(1.69±0.11)、(1.39±0.1)μmol/L; RT-PCR和免疫印迹实验显示,与0 μmol/L硫链丝菌素组比较,1、1.5、2μmol/L硫链丝菌素组细胞FoxMl mRNA及蛋白水平下降,G2/M期细胞细胞比例和凋亡率升高,凋亡蛋白bax表达增加,抗凋亡蛋白bcl-2表达减少,且均呈浓度依赖性,差异有统计学意义(P＜0.05). 结论 FoxM1抑制剂硫链丝菌素可明显抑制Daoy细胞增殖,可能与阻滞细胞周期于G2/M期、改变bcl-2/bax表达诱发凋亡有关.     

β-淀粉样肽(25-35)对PC12细胞前列腺凋亡反应蛋白-4和bcl-2基因表达的影响

目的观察β-淀粉样肽（25-35）（β-amyloid peptide 25-35，Aβ-25-35）诱导PC12细胞凋亡及对前列腺凋亡反应蛋白-4（prostate apoptosis response-4，par-4）和bcl-2基因表达的影响。方法采用MTT比色法分析细胞存活率，Hoechst33258-PI荧光染色观察细胞核凋亡的形态学改变，RT-PCR检测par-4和bcl-2基因mRNA表达变化，Western blot检测Par-4和Bcl-2蛋白表达变化。结果 随Aβ23-35浓度的增加，PC12细胞存活率降低，荧光染色可见细胞核固缩、核碎裂，par-4 mRNA及蛋白表达增加，bcl-2 mRNA及蛋白表达降低。结论 在Aβ25-35诱导PC12细胞凋亡过程中Par-4和Bcl-2蛋白分子可能起重要作用。     

G422胶质瘤冷冻后细胞凋亡及相关基因表达的研究

目的：探讨冷冻杀伤肿瘤细胞的分子机制。方法；建立小鼠脑胶质瘤动物模型；用末端标记法（TUNEL）原位检测细胞凋亡，DNA琼脂糖电泳观察DNA梯形条带；用免疫组织化学ABC法检查bcl-2和bax表达。结果：不同冻融周期作用于G422胶质瘤后，在不同时间点、冷冻灶周边区的肿瘤细胞出现了形态学和DNA水平上的细胞凋亡变化，其峰值出现在冷冻后24-48h。重复冻融出现更多的凋亡细胞。不同冻融周期均引起冷冻灶周边区细胞bax上调，但对抑凋亡基因bcl-2表达无明显影响。结论：冷冻治疗可以诱导G422胶质瘤细胞凋亡，冷冻诱导的细胞凋亡由bax基因参与介导，而与bcl-2表达无关。诱导细胞凋亡可能 是冷冻杀伤肿瘤细胞的重要机制。     

水溶性β-淀粉样蛋白25-35片段诱致大鼠嗜铬细胞瘤细胞凋亡

目的　探讨β-淀粉样蛋白 ( Aβ)在形成淀粉样沉积前对体外培养的 PC1 2细胞的毒性作用。方法　应用流式细胞仪检测 Aβ的剂量依赖性毒性 ;应用 DNA琼脂糖凝胶电泳、DNA末端标记和电镜判断 Aβ损伤细胞的途径。结果　流式细胞仪检测发现随着 Aβ2 5 -35浓度的增加 ,PC1 2细胞的死亡率增加 ;加入 1 0 μmol/L Aβ2 5 -35 2 4 h后 ,经 TUNEL发现细胞核着色 ,并可见细胞核碎片 ;DNA琼脂糖凝胶电泳可见间隔 1 80～ 2 0 0 bp左右的梯度条带 ;电镜显示细胞核浓缩 ,胞浆内有空泡形成 ,胞浆内细胞器完好。结论　 Aβ在形成纤维状沉积前即对神经细胞有毒性作用 ,可促进神经细胞的凋亡。     

壳寡糖对Hela细胞cyclin D1、bcl-xl和bcl-2 mRNA表达的影响

背景：研究表明壳寡糖具有抗肿瘤作用,但壳寡糖对cyclin D1、bcl-2和bcl-xl影响机制尚不清楚。 目的：观察壳寡糖抑制Hela细胞生长的作用,以及对细胞内cyclin D1、bcl-xl和 bcl-2 mRNA表达的影响。 方法：壳寡糖(0.1,0.5,1,2,5 g/L)刺激Hela细胞后,CCK8实验检测其对细胞生长的影响;运用实时荧光定量PCR方法在分子水平检测cyclin D1、bcl-xl和 bcl-2 mRNA在细胞中的表达情况。 结果与结论：壳寡糖可抑制Hela细胞的生长;随着壳寡糖的质量浓度由0.1 g/L增加至2 g/L,壳寡糖抑制cyclin D1,bcl-2,bcl-xl基因表达的作用也逐渐增强,在2 g/L时作用最强,但质量浓度过高时(5 g/L)抑制作用反而有所减弱。结果表明壳寡糖的抗肿瘤作用可能通过两方面进行：一方面壳寡糖可以抑制与细胞周期有关的cyclin D1 mRNA表达以抑制肿瘤细胞的增殖;另一方面壳寡糖可以抑制抗凋亡蛋白Bcl-2 和bcl-xl mRNA的表达以促进肿瘤细胞的凋亡;且对前者的作用强于后者。 关键词：荧光定量PCR;壳寡糖;Hela细胞;细胞周期蛋白 D1;bcl-xl;bcl-2 doi:10.3969/j.issn.1673-8225.2010.03.012     

睾酮对Aβ25-35诱导PC12细胞凋亡保护机制的研究

目的 探讨睾酮对Aβ25- 35诱导PC12细胞凋亡的保护作用机制.方法 MTT法观察睾酮对Aβ25-35诱导PC12细胞凋亡后细胞活性的影响;Hochest—PI染色观察睾酮对Aβ25- 35诱导PC12细胞凋亡形态学的影响;Western免疫印迹法和Real — time PCR法观察睾酮对Aβ25- 35诱导PC12细胞凋亡相关调控因子bcl-XL、Bax蛋白及mRNA表达的影响.结果 与对照组相比,睾酮预保护后可以明显抑制Aβ25-35诱导PC12细胞凋亡后细胞活性及细胞形态学变化,并上调bcl-XL蛋白及mRNA、下调Bax蛋白及mRNA的表达,雄激素受体拮抗剂氟他胺干预后可以明显抑制睾酮的保护效应.结论 睾酮保护Aβ25-35诱导的PC12细胞凋亡活动,其潜在作用机制可能是通过AR介导的基因信号传导通路在蛋白表达和基因转录水平上抑制Bax、上调bcl-XL的表达实现.     

2002/原花青素对β-淀粉样肽（25-35）诱导去血清培养PC12细胞细胞周期分布的影响

目的 探讨原花青素 (Procyanidins,PC) 对β-淀粉样肽（25-35）[βamyloid peptide -(25-35),Aβ25-35] 诱导去血清培养PC12细胞的凋亡及细胞周期分布的影响。方法 流式细胞仪检测细胞周期分布情况及细胞凋亡率;RT-PCR 检测 p53基因 mRNA 表达;Western blot检测 P53蛋白表达。 结果 30mg/L PC预处理 PC12 细胞 1 h ,可降低Aβ25-35引起的去血清培养PC12细胞凋亡率,逆转Aβ25-35引起的去血清培养PC12细胞的细胞周期S期阻滞,降低 p53 mRNA及P53蛋白表达。 结论 PC可对抗Aβ25-35 诱导的去血清培养 PC12 细胞的凋亡及细胞周期S期阻滞,其机制可能与下调p53基因表达有关。     

重组pIRES-AD7c-NTP质粒的构建表达及其对PC12细胞凋亡的影响

目的构建重组pIRES-AD7c-NTP质粒,探究其对PC12细胞凋亡的影响。方法构建pIRESAD7c-NTP重组质粒,通过脂质体体外转染至PC12细胞内,RT-PCR检测凋亡相关蛋白bcl-2和bax的mRNA表达变化含量变化。结果成功构建pIRES-AD7c-NTP重组质粒并转染至PC12细胞内;重组质粒转染组出现了明显的细胞凋亡,流式细胞仪检测出典型凋亡峰;重组质粒转染组中bcl-2表达低于对照组,bax表达高于对照组。结论 AD7c-NTP重组质粒转染组PC12细胞内bcl-2/bax表达异常,说明AD7c-NTP增加凋亡促进蛋白的表达、同时减少凋亡抑制蛋白的表达,可见AD7c-NTP可导致神经细胞发生凋亡,为后续研究提供实验基础。     

流式细胞术检测局灶性脑缺血再灌注bcl-xl、bax蛋白表达

目的 探讨应用流式细胞术检测bcl-xl和bax在局灶性脑缺血再灌注中的表达及作用。方法 45只健康雄性Wistar大鼠随机分为正常对照组、假手术组。缺血3 h组和缺血3 h再灌注组;缺血再灌注组又分为缺血再灌注3h、6h、12h、24h、48h和72h等6个亚组。采用线栓法复制大脑中动脉脑缺血再灌注模型,应用流式细胞术检测bcl-xl和bax蛋白表达。结果 缺血3 h再灌注各亚组,随再灌注时间的延长,半影区bax表达逐渐增强,于再灌注24 h和48 h达高峰(均P<0.01);bcl-xl表达在早期增强后随即呈下降趋势,bcl-xl/bax比值呈动态变化。再灌注中心区,在缺血再灌注早期bcl-xl和bax表达均增强(P<0.05或P<0.01),随着再灌注时间的延长,二者的表达及bcl-xl/bax比值逐渐减弱。结论 bcl-xl表达增强有利于促进神经细胞存活,而bcl-xl与bax比值的转变则促进神经细胞凋亡。     

Mental illness in England,in Scotland and in Scots living in England

Summary Beginning from the observation that Scots living in England have much higher rates of mental hospital admission than do the English, several hypotheses are proposed to account for this. Much of the excess in rates of mental illness is accounted for by those diagnosed as having alcohol-related disorders and behaviour and personality problems. The results of an examination of offical statistics in the two countries enabled some explanations to be offered. It was found that rates of admissions to mental hospitals are higher in Scotland than in England but not as high as those found among Scots migrants who have a much higher rate of readmission to hospitals than either of the other groups. In fact, if first admissions only are considered the rates of admission in Scotland are not only higher than rates for English natives but also higher than for Scottish migrants. It seems that Scots living in England are somewhat less likely to become mental patients than Scots in Scotland but that once they do achieve this status they are very much more likely to be readmitted on subsequent occasions. It was concluded that there might be two fairly distinct groups of migrants from Scotland to England who have different backgrounds, different reasons for migrating and different psychological characteristics. On the one hand there are stable, economically motivated migrants who move south for definite employment related reasons and who show few psychological symptoms. While on the other hand there is a group of migrants who perhaps have psychological problems and who move more in hope than expectation without definite prospects and who account for the high rates of mental hospital admission found in Scottish migrants.     

Prostacyclin release in the coronary circulation during sustained stimulation in in vitro and in in vivo experimental systems

Prostacyclin release from rat isolated perfused hearts and from dog coronary circulation was studied by measuring immunoreactive 6-keto-PGF1 alpha (6-keto-PGF1a) in heart perfusate and in plasma obtained from the great cardiac vein respectively. Continuous infusion of arachidonic acid at constant concentration in isolated perfused hearts induced an increased prostacyclin release. This release showed a rapid peak within 10 min and a subsequent decrease. Low-flow ischemia induced an increased perfusate concentration of 6-keto-PGF1a but, considering the decreased flow, prostacyclin release was actually reduced. During the whole period of ischemia (60 min) prostacyclin release was constant. In open-chest anesthetized dogs 6-keto-PGF1a concentration in the great cardiac vein was increased after ligation of the left anterior descending coronary artery. A prolonged period of coronary occlusion (4.5 hours) resulted in a progressive rise of prostacyclin release. 6-keto-PGF1a determinations in the femoral vein and in the aorta did not show relevant variations during the observation period.     

癫痫与抑郁关系的研究进展

抑郁是癫痫患者中常见的精神障碍,严重地影响了患者的生活质量。传统的观点认为癫痫患者因为存在着诸多社会学问题易出现抑郁倾向,癫痫和抑郁是单向的联系,但大量的研究已经证明癫痫和抑郁之间存在双向的联系,一种异常状态的存在可能易转化为另一种异常状态的发展。癫痫和抑郁存在着共同的发病机制。本文主要就癫痫和抑郁的双向联系以及抗抑郁药物在癫痫患者中的应用进行阐述。     

神经介入：回眸2022

<正>2022年,国际上公布了多项大型神经介入领域的随机对照试验（randomized controlled trial,RCT）结果,在血管内治疗（endovascular treatment,EVT）急性大血管闭塞（large vessel occlusion,LVO）适应证的扩展、药物治疗、管理,症状性颅内动脉粥样硬化性狭窄（symptomatic intracranial atherosclerotic stenosis,sICAS）治疗,无症状性颈动脉狭窄治疗,     

Neuroimaging in epilepsy in tropics

Epilepsy is a major public health problem in many tropical countries. Also, some of the tropical diseases are major contributors to the higher prevalence of epilepsy in these countries. The etiologic factors responsible for epilepsy in these countries are quite different from those in the developed world. This article discusses the etiologic factors and neuroimaging of epilepsy in light of the conditions in these tropical countries.     

Sudanophilic lipid accumulation in astrocytes in periventricular leukomalacia in monkeys

Summary Sudanophilic lipid accumulation is a characteristic feature of periventricular leukomalacia (PVL) of infants. At least two types of lipid-containing cells have been identified, one being the macrophage, the other the pre-myelin glial cell. A third type of lipid-containing cell has been seen in two monkeys with spontaneous PVL. Electron microscopically this cell appears to be an astrocyte. This probably represents a reaction of the astrocyte to hypoxia and may be the equivalent of the hypertrophic astrocytes found in human infants.Supported in part by NIH grant HDO 8633 and the Regional Primate Research Center Grant RR-00166