西酞普兰对慢性应激大鼠海马CA1、CA3区神经细胞凋亡的影响

目的：探讨西酞普兰对慢性应激大鼠海马CA1、CA3神经细胞凋亡的影响。方法: 将40只雄性SD大鼠随机分为空白、对照（生理盐水灌胃）、实验1-3组（分别以8 mg·kg-1·d-1、4 mg·kg-1·d-1、1 mg·kg-1·d-1氢溴酸西酞普兰灌胃），每组8只，采用强迫游泳制造慢性应激大鼠模型，用大鼠悬尾实验、力竭实验观察行为学，苏木素伊红（HE）染色观察CA1、CA3神经细胞凋亡，脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测和尼康图像分析（NIS BR）软件测量CA1、CA3神经细胞凋亡数量及积分吸光度值。结果: 对照组静止不动时间延长、挣扎次数减少，实验组静止不动时间缩短、力竭时间延长、挣扎次数增多；对照组CA1、CA3区阳性细胞增多,CA3区阳性细胞积分吸光度值变小；各实验组阳性细胞数量减少，实验1、3组CA1、CA3区阳性细胞积分吸光度值增大。结论: 西酞普兰对慢性应激大鼠海马CA1、CA3神经细胞具有保护作用，提示西酞普兰对慢性应激引起的神经精神疾病的治疗机制，可能是通过拮抗CA1、CA3区神经细胞凋亡而起作用。     

穴位埋线对血管性痴呆大鼠海马CA1区神经细胞凋亡的影响

目的 观察穴位埋线疗法对血管性痴呆（VD）大鼠海马CA1区神经细胞凋亡和Bcl-2 mRNA及Bax mRNA表达的影响,探讨穴位埋线对VD大鼠脑缺血性损伤的神经保护机制。 方法 采用改良Pulsinelli’s 4血管阻断法建立VD大鼠模型,随机数表法分为VD模型组、穴位埋线组、尼莫地平组,并设置假手术组作为对照。两个治疗组分别施行穴位埋线和尼莫地平治疗。Morris 水迷宫检测各组大鼠学习记忆能力后,取含海马的脑组织,TUNEL法检测海马CA1区神经细胞凋亡,原位杂交法检测其Bcl-2 mRNA及Bax mRNA表达,观察并比较各组大鼠海马神经细胞凋亡、蛋白表达的变化。 结果 VD模型组大鼠海马CA1区可见大量凋亡细胞、Bcl-2 mRNA 表达降低、Bax mRNA 的表达增高,与假手术组比较差异均有统计学意义（P＜0.01）。VD模型组表现出明显的学习记忆障碍,与假手术组相比差异有统计学意义（P＜0.01）;与VD模型组比较,穴位埋线组大鼠学习记忆能力显著提高（P＜0.01）,CA1区凋亡细胞明显减少（P＜0.01）,可见一定数量的Bcl-2 mRNA阳性细胞表达,而Bax mRNA阳性细胞表达较少。 结论 穴位埋线可通过上调VD大鼠海马CA1区Bcl-2 mRNA的表达、下调Bax mRNA 的表达,抑制海马神经细胞凋亡,改善VD大鼠学习记忆能力。     

猪心大静脉血栓性闭塞后心肌细胞凋亡与Bcl-2、Bax的表达

目的：探讨心大静脉血栓后不同时间、不同部位心肌细胞凋亡及其调控基因Bcl-2、Bax的变化。方法：应用流式细胞法和TUNEL法测定24头家猪心大静脉血栓栓塞不同时间、不同部位心肌细胞凋亡率；流式细胞法测定Bcl-2、Bax在血栓后的表达。结果：心大静脉血栓栓塞后，心肌细胞凋亡率明显增加，以血栓对侧心肌细胞凋亡率最高，血栓前、血栓后1-4周采用流式细胞法检测心肌细胞凋亡率分别为：(3.70±0.66)%，(7.54±1.18)%，(5.64±0.93)%，(4.72±0.98)%，(3.53±0.52)%。心大静脉血栓1周后，血栓远端心肌细胞Bcl-2表达与对照组比较明显降低（32.30±1.77 vs 25.67±5.07，P<0.01），以后与对照组比较无差异；2周后，血栓对侧心肌细胞Bcl-2表达增高。心大静脉血栓后，心肌细胞Bax表达在各个部位均增高，并持续至血栓后4周。Bcl-2/Bax在血栓1周后明显降低，以后逐渐接近血栓前水平。结论：心大静脉血栓可造成心肌细胞凋亡，Bcl-2、Bax在此过程中起重要作用，但两者存在部位差异。     

银杏内酯B对体外培养的大鼠视网膜神经细胞凋亡的影响

目的： 观察银杏内酯B对体外培养的大鼠视网膜神经细胞凋亡的影响及可能的作用机制。 方法： 采用体外原代培养的大鼠视网膜神经细胞，建立谷氨酸损伤的视网膜神经细胞凋亡模型，与不同浓度的银杏内酯B（ginkgolide B，GB）共同培养，用MTT法测定神经细胞存活率；流式细胞仪检测神经细胞凋亡及其相关基因Bcl-2和Bax蛋白表达。 结果： 谷氨酸（0.8 mmol/L）作用后，视网膜神经细胞存活率降低。GB不同时间及不同剂量作用组与谷氨酸处理组比较，视网膜神经细胞内Bcl-2和Bax阳性蛋白表达及两者比值均有显著差异（P＜0.01），细胞凋亡明显减少。 结论： GB能剂量依赖性对抗谷氨酸兴奋性毒性, 保护视网膜神经细胞，这一作用可能是通过促进Bcl-2蛋白表达并减少Bax蛋白表达，上调Bcl-2/Bax比值而抑制视网膜神经细胞凋亡来实现的。     

表没食子儿茶素没食子酸酯对缺血再灌注心肌细胞凋亡的作用

目的：观察表没食子儿茶素没食子酸酯（EGCG）对缺血再灌注损伤大鼠心肌细胞凋亡的影响。 方法： 采用结扎大鼠左冠状动脉前降支30 min，然后松开再灌注60 min的方法，复制大鼠心肌缺血再灌注损伤模型。实验分假手术组、缺血再灌注组（IR）、EGCG不同剂量治疗组和丹参（SM）组。用原位缺口末端标记法（TUNEL）检测心肌凋亡细胞，用链酶亲和素-生物素-酶复合物（SABC）免疫组化法检测凋亡相关基因Bcl-2和Bax蛋白表达。 结果： 在假手术组未发现凋亡细胞，IR组细胞凋亡明显，Bcl-2和Bax蛋白表达增加，但以Bax更明显，Bcl-2/Bax值显著低于假手术组（P<0.01）；EGCG组凋亡细胞明显少于IR组，Bcl-2表达显著大于而Bax表达显著少于IR组，Bcl-2/Bax值显著高于IR组（P<0.01）。 结论： EGCG能明显抑制IR引起的心肌细胞凋亡，其作用机制可能与下调Bax和上调Bcl-2蛋白表达，提高Bcl-2/Bax值有一定关系。     

神经调节素对实验性痴呆大鼠的干预作用和可能机制

目的探讨神经调节素1β(NRG1β)对实验性老年痴呆大鼠神经元凋亡及Bcl-2和Bax表达的影响。方法成年健康雄性Wistar大鼠30只,随机分为假手术组、模型组、治疗组各10只,经左侧脑室微量注射淀粉样蛋白β1-40(Aβ1-40)建立实验性痴呆模型,经右侧脑室注射NRG1β干预治疗,Y型电迷宫检测大鼠的认知功能,原位缺口末端标记法(TUNEL)检测神经细胞凋亡,免疫组织化学法检测Bcl-2和Bax表达。结果造模成功后,模型组大鼠较对照组认知能力明显下降,TUNEL阳性细胞数明显增多,神经细胞Bcl-2和Bax蛋白表达增强(P0.05)。经NRG1β治疗后,治疗组大鼠较模型组认知能力显著改善,TUNEL阳性细胞显著减少,Bcl-2表达增强,Bax表达减弱(P0.05)。结论 NRG1β可能通过调节Bcl-2和Bax表达而抑制神经细胞凋亡,从而改善实验性痴呆大鼠学习记忆能力。     

颈动脉狭窄影响大鼠认知功能及海马神经元凋亡

目的:研究改善颈动脉狭窄对大鼠认知功能、海马神经元凋亡及bcl-2、Bax蛋白表达的影响.方法:采用SD大鼠制作颈动脉狭窄模型,2周后将颈动脉狭窄解除,4周后各组采用Morris水迷宫检测记忆能力、HE染色观察神经元形态学变化、TUNEL法观察海马神经元凋亡、免疫组织化学检测Bcl-2、Bax蛋白表达.结果:对照组与假手术组比较,大鼠记忆能力明显下降(P<0.01),神经细胞凋亡率明显增高(P<0.01),Bcl-2和Bax免疫阳性细胞数增多(P<0.01),改善狭窄组较对照组记忆能力明显改善(P<0.01),神经细胞凋亡率明显低于对照组(P<0.05),Bcl-2免疫阳性细胞数明显增多(P<0.05),Bax免疫阳性细胞数明显减少(P<0.05).结论:改善颈动脉狭窄可提高大鼠海马Bcl-2蛋白的表达,抑制海马神经细胞凋亡,改善认知功能障碍.     

低分子肝素抗新生大鼠大脑皮层神经细胞缺氧性凋亡

目的：探讨低分子肝素对体外培养的新生大鼠大脑皮层神经细胞缺氧性凋亡的作用机制。方法： 应用“neurobasal 加 B27 supplement”体外培养大鼠大脑皮层神经细胞，并在缺氧条件下使用Hoechst 33342荧光染色法、免疫细胞化学染色法观察低分子肝素对原代神经细胞的抗凋亡作用。结果： 在250-500 U/L的浓度范围內，低分子肝素能降低缺氧诱导的神经细胞凋亡率（P<0.05），并且较BDNF（50 μg/L）抗凋亡阳性对照组的凋亡率更低（P<0.05）。低分子肝素（500 U/L）增加缺氧的神经细胞Bcl-2蛋白的表达（P<0.05），减少Bax蛋白的表达（P<0.01），提高Bcl-2/Bax比值（P<0.01）。低分子肝素500 U/L组的Bcl-2/Bax比值比正常对照组、BDNF抗凋亡阳性对照组和凋亡阳性组都高（P<0.05）。结论： 低分子肝素通过上调缺氧神经细胞Bcl-2表达和下调Bax表达，提高Bcl-2/Bax比值减少缺氧的神经细胞凋亡。     

糖调节受损大鼠学习记忆能力下降与海马神经细胞凋亡有关

目的探讨糖调节受损大鼠海马神经细胞凋亡与学习记忆能力的关系。方法用高脂高糖饲料饲养法建立糖调节受损大鼠模型;用Morris水迷宫法检测学习记忆能力;用TUNEL法检测海马神经细胞凋亡数目;用免疫组化和原位杂交技术检测海马神经细胞Bcl-2/Bax和Bcl-2 mRNA/Bax mRNA的表达。结果与NGT组相比,IGR组学习记忆能力下降(P0.05),海马神经细胞凋亡数增高(P0.05),Bcl-2、Bcl-2 mRNA表达减少(P0.05),Bax与Bax mRNA表达增加(P0.05)。IGR组学习、记忆能力与Bcl-2阳性表达呈正相关(P0.05),与Bax阳性表达呈负相关(P0.05)。结论糖调节受损与大鼠学习记忆能力下降有相关性,海马神经细胞凋亡可能是其重要机制之一。     

叶酸拮抗同型半胱氨酸诱导的内皮细胞凋亡的作用机制

目的： 明确同型半胱氨酸（Hcy）对内皮细胞凋亡的影响以及叶酸的拮抗作用，阐明Bax和Bcl-2在同型半胱氨酸诱导内皮细胞凋亡及叶酸拮抗中的作用。方法: 用不同浓度的Hcy处理内皮细胞后，应用末端转移标记技术（TUNEL）以及Annexin V/PI染色加流式细胞术了解细胞凋亡状态，免疫组化方法检测Bax、Bcl-2的表达。结果: Hcy能促进细胞凋亡，叶酸具有拮抗作用。Hcy能促进细胞Bax、Bcl-2的表达，上调Bax/Bcl-2比值，叶酸能减少细胞表达Bax及Bcl-2，下调Bax/Bcl-2比值。结论: Bax、Bcl-2参与了Hcy诱导内皮细胞凋亡以及叶酸拮抗作用的过程。     

Rate of neurite outgrowth in sympathetic neurons is highly resistant to suppression of protein synthesis: role of protein degradation/synthesis coupling

Neurites projecting to their target tissues during embryogenesis are subject to many perturbations that could influence their rate of growth. For example, environmental influences such as supply of neurotrophic factor or electrical activity profoundly influence the rate of neuronal protein synthesis. Because accumulation of protein is necessary for outgrowth to proceed normally, a perturbation in protein synthesis could cause a net change in the rate of accumulation of proteins with the result that neurite outgrowth rate increases or decreases. That neurite outgrowth does not normally seem to be subject to such perturbations suggests involvement of a homeostatic system controlling the rate of outgrowth. Consistent with this hypothesis, we show here that the rate of growth of neurites of sympathetic neurons is highly resistant to decreased rates of protein synthesis. Chronic suppression of protein synthesis by 60% had no significant effect on neurite outgrowth over a 2-day period while complete suppression halted it almost immediately. By the 3rd day of exposure, 60% suppression slowed outgrowth. Sustained suppression of protein synthesis rate by 33% had no effect on rate of outgrowth even after 7 days. We show that the ability of the growing neurites to resist protein synthesis suppression appears to be caused, at least in part, by a parallel decrease in the rate of protein degradation. The result of this coupling between degradation and synthesis is that proteins can continue to accumulate even when protein synthesis rate decreases, allowing normal rates of neurite outgrowth.     

Purification and identification of simian parvovirus protein Vp2 expressed in E.coli

Simian parvovirus (SPV) was originally isolatedfrom cynomolgus macaques with severe anemia[1] .The clinical features of the SPVinfectioninthese monkeys show many similarities to those ofthe parvovirus B19 infections in humans [2] .Inaddition,the genomic organization protein codingstrategies of SPVare also very similar to those ofhuman parvovirus B19 .It is well knownthat SPVcontains both positive and negative single-strandedDNA,andthe positive stranded DNAcontainstwolarge openreadingfr…     

端粒重复因子2与p53的体外结合

目的 通过分析端粒主要结合蛋白端粒重复因子2(TRF2)与p53的体外结合,探讨p53通过端粒途径调节细胞增殖、衰老和凋亡的分子机制。方法 4种不同的p53-谷胱甘肽S转移酶(glutathione S-transferase,GST)融合蛋白和GST经大肠杆菌表达、谷胱甘肽-Sepharose^TM 4B纯化,其中的人重组p53包括野生型(1～393)、C端缺失体p53 N5(2～293)、N端缺失体p53 N5(95～393)、第175位氨基酸突变体(R→H)。将各纯化蛋白和人乳腺癌细胞MCF-7的细胞蛋白进行体外结合反应(pull down),Western blot检测反应物中p53和TRF2的结合。结果 纯化的GST和p53-GST融合蛋白纯度均在90％以上,且相对分子质量与预计的完全一致。TRF2的Western blot显示：野生型p53和p53-R 175H均能沉淀MCF-7中的TRF2,且结合力相似,而单独的GST则无沉淀TRF2的作用。与野生型p53和p53 R175H相比,p53 2C与TRF2的结合力相对增加,p53 N5与TRF2的结合力相对大大减弱。结论 p53和TRF2可以进行直接而特异的体外结合,且其结合部位在p53的C端(293～393)。p53和TRF2的C端依赖性结合可能与端粒动态变化所诱导的细胞活动有关。     

Laminin和survivin的表达与胆囊癌临床病理特征的关系

目的:研究laminin和survivin蛋白在原发性胆囊癌组织中的表达情况,及其与癌组织类型、病理分级和转移状况的关系。 方法:应用免疫组织化学方法检测49例原发性胆囊癌、21例胆囊腺瘤和13例慢性胆囊炎组织中laminin和survivin蛋白的表达。 结果:胆囊黏膜内癌或原位癌细胞基底膜laminin线性染色完整；NevinⅡ期胆囊癌组织表现为基底膜不完整,变薄,断裂,或缺损；临床NevinⅢ、Ⅳ、Ⅴ期胆囊癌，则无基底膜形成，在肿瘤组织周围，laminin表达类型呈碎片状或断线状和连续线状，部分癌组织内laminin染色消失和癌细胞浆内有laminin弱染色。胆囊癌组织中survivin阳性表达率明显高于胆囊腺瘤和慢性胆囊炎组织，但survivin的阳性表达与胆囊癌细胞分化程度、病理分级和转移无关(P>0.05)。且胆囊癌组织中laminin的连续线断裂或缺失,与胆囊癌组织中survivin的表达情况无相关性。 结论:胆囊癌基质中laminin的表达类型与胆囊癌的侵袭和转移有关，而survivin在胆囊癌中表达增加，但两者之间似乎无关联。      

Relation of plasma protein oxidation parameters and paraoxonase activity in the ageing population

The incidence of atherosclerosis increases with age. Oxidative changes in proteins and lipids are considered to be among the molecular mechanisms leading to endothelial dysfunction. Paraoxonase (PON1) is exclusively associated with high-density lipoprotein (HDL) and protects both HDL and low-density lipoprotein (LDL) from oxidation. PON1 has two cysteine residues for its antioxidant function. We investigated the relation between PON1 activity and protein oxidation parameters such as protein hydroperoxides (P-OOH), protein carbonyl (PCO), total thiol (T-SH) and advanced oxidation protein products (AOPP). Our study also covered other oxidative stress parameters such as oxidised LDL (oxLDL) and superoxide dismutase activity in the plasma of young, middle-aged and elderly individuals. PON1 activity of elderly and middle-aged individuals was decreased significantly compared with that in the young group. oxLDL levels of elderly individuals were increased significantly compared with those of both the young and middle-aged individuals. P-OOH, PCO and AOPP levels of the elderly and middle aged individuals were higher compared with those of the young. On the other hand, T-SH levels of the elderly and middle-aged individuals were lower compared with those of the young. Side by side with the decrease in the T-SH levels in the middle-aged and elderly groups as compared to the young, the increase we have observed in other protein oxidation parameters in the groups leading to decreasing PON1 activity might, we think, create a predisposition to atherosclerosis.     

Age-dependent changes of nuclear envelope protein phosphokinase and protein phosphatase activities. Significance for altered nucleo-cytoplasmic mRNA translocation during development

Nuclear envelopes are associated with a protein phosphokinase and a phosphoprotein phosphatase, whose activities are modulated by poly(A) in an opposite manner. The activities of these enzymes were determined in nuclear ghosts from liver and oviduct of quails of different age and of different hormone status. Under optimal conditions, kinase activity was found to increase in immature animals 8-fold in response to diethylstilbestrol; co-administration of progesterone had no marked effect on enzyme activity. After the initial burst, the activity of the enzyme increased only slightly during ageing. Two proteins present in nuclear ghosts of Mr 64 000 and of Mr 106 000 are phosphorylated during the kinase reaction; both the relative and the absolute extents of phosphate incorporation into these proteins alter drastically during ageing or hormone treatment of immature animals. Like the kinase activity, the activity of protein phosphatase increased in immature animals markedly in response to hormone treatment. Thereafter the activity remained constant in liver while in oviducts the phosphatase activity dropped to 30% in both mature and old animals.     

A蛋白基因在枯草杆菌R25及地衣芽孢杆菌NM105中的表达

目的：测定Ａ蛋白基因在Ｒ２５及ＮＭ１０５中的表达情况。方法：根据Ａ蛋白基因产物－Ａ蛋白能特异地与许多动物的免疫球蛋白的Ｆｃ段结合这一特性，采用ＥＬＩＳＡ检测法测定。结果：在细菌生长对数期，表达量与酶活性都在快速上升，在细胞生长平台期，表达量呈下降趋势。加中性蛋白酶抑制剂，使表达量提高了４６％，低酶活性培养基的表达量是ＬＢ培养基的７．４倍，在碱性蛋白酶缺失的Ｒ２５中的表达量是ＮＭ１０５的１．６倍。结     

Tat融合蛋白表达载体TAT-SOX2的克隆化及蛋白表达研究

目的 构建重组表达载体TAT-SOX2,在E.coli BL21中高效表达并纯化融合蛋白.方法 经PCR获得编码人SOX2的全基因序列,连接到原核表达载体PET-28b-TAT-V2上,得到重组表达载体TAT-SOX2,转化大肠埃希菌,IPTG诱导TAT-SOX2融合蛋白的表达.表达产物用SDS-PAGE鉴定,亲和层析柱纯化融合蛋白,并应用Western Blot检测蛋白的特异性,应用免疫荧光检测融合蛋白转导HSF细胞的效果.结果 成功构建了TAT-SOX2融合蛋白的原核表达载体,在诱导下获得了高效表达并纯化了融合蛋白,Western Blot鉴定正确.免疫荧光提示融合蛋白可快速转导入HSF细胞内.结论 为进一步的通过蛋白转导方式诱导多能干细胞提供了物质基础.     

hHBrk1与WAVE1蛋白相互作用位点的鉴定

目的: 鉴定微丝相关蛋白hHBrk1与WAVE1的结合位点。方法: 利用PCR的方法克隆人 WAVE1 及各结构域的基因片段,并将之亚克隆至真核表达载体;免疫共沉淀技术检测hHBrk1与WAVE1结合位点。结果: 获得了 WAVE1 及各结构域基因的真核表达载体;免疫共沉淀发现hHBrk1与WAVE1的Scar同源结构域(SHD)结合,而WAVE1蛋白结合于hHBrk1的羧基端,羧基端七肽重复(HR)结构域点突变后获得的蛋白失去了与WAVE1的结合能力。结论: hHBrk1可能通过HR结构域与WAVE1的SHD区结合,参与WAVE1蛋白的细胞亚定位或维持其稳定性,从而调控肿瘤细胞的迁移。     

Experimental and theoretical study of selective protein deposition using focused micro laminar flows

The present work describes an experimental method and design tools which enable the precise localization of an analyte, a few microns in width, both temporally and spatially using laminar flows and thus improves previous methods in hydrodynamic focusing. The technique is used to adsorb proteins to selected regions within a microfluidic device without any contamination of the surroundings and may serve in applications requiring selective conveying of other reagents. The regions not coated by proteins are modified with poly(ethylene glycol; PEG), known to efficiently resist protein and cell adhesion. Human endothelial and fibroblast cells are later introduced into the device selectively attaching to the protein coated regions and cultured for a few days. A simulation of the convection–diffusion characteristics of the system is presented and compared to the known T-sensor. The results reveal that, by proper design, reagents concentration may be kept nearly constant along the flow direction. This phenomenon is demonstrated here by achieving particularly precise patterning of cells but may be utilized for numerous other applications as well. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.