枸杞多糖对人白血病细胞株凋亡的影响

目的 :　探讨枸杞多糖 ( LBP- X)对人白血病 HL- 60细胞凋亡的影响。方法 :　 LBP-X与 HL- 60细胞共培养 ,MTT法检测 LBP- X对 HL- 60细胞增殖的抑制作用 ;以 DPH为荧光探针检测细胞膜流动性的变化 ;用 Hoechst332 5 8染色在荧光显微镜下观察细胞核形态学变化 ;琼脂糖凝胶电泳法和流式细胞仪检测法定性定量检测细胞凋亡。结果 :　LBP- X2 0～ 1 0 0 0 mg/L呈剂量依赖性抑制 HL- 60细胞增殖 ,且可降低 HL- 60细胞膜的流动性 ;LBP- X作用 48h后 ,荧光显微镜下细胞核固缩、凝聚和断裂 ,出现浓染致密的颗粒块状荧光 ;DNA琼脂糖凝胶电泳可见明显的“DNA条带”;流式细胞仪分析图上出现凋亡峰。结论 :　 LBP- X对诱导人白血病 HL- 60细胞凋亡有一定作用。     

马鞭草诱导人绒毛膜癌JAR细胞凋亡作用观察

[目的]探讨马鞭草C部位对人绒癌JAR细胞抑制作用机理. [方法]通过相差显微镜观察活细胞贴壁程度、细胞形态改变;荧光显微镜观察细胞形态学变化;透射电镜观察细胞超微结构变化;琼脂糖凝胶电泳观察用药后细胞DNA断裂情况;流式细胞仪检测细胞凋亡情况. [结果]马鞭草C部位可引起细胞数目减少并萎缩;荧光显微镜下观察到典型凋亡细胞的形态学特征;电镜下见到明显的凋亡小体;琼脂糖凝胶电泳出现"阶梯状条带";流式细胞仪检测发现用药后出现明显的凋亡峰. [结论]马鞭草C部位对人绒癌JAR细胞抑制作用机理是诱导其凋亡.     

苯体外诱导小鼠骨髓细胞凋亡的研究

目的 观察苯对离体小鼠骨髓细胞的凋亡诱导作用。方法 荧光染色法检测细胞形态;DNA凝胶电泳法观察DNA裂解片段;流式细胞仪测细胞DNA含量法检测细胞凋亡率。结果 荧光染色法检测显示苯诱导小鼠骨髓细胞出现典型的凋亡特征形状;DNA凝胶电泳检测出苯诱导终浓度为15、25mmol/L,诱导时间为3h,电泳图谱呈现典型的DNA梯型条带;流式细胞仪检测DNA含量结果表明苯诱导小鼠骨髓细胞凋亡呈剂量－效应和时间－效应关系。结论 在体外培养条件下,苯是一种小鼠骨髓细胞凋亡诱导剂。     

2,5-己二酮诱导的PC12细胞损伤和凋亡

目的建立2,5己二酮诱导的PC12细胞凋亡模型。方法以PC12细胞为神经元的细胞模型,将2,5己二酮(30、40、50mmol/L)加入培养的PC12细胞中,四甲基偶氮唑盐检测细胞活性,Hochest33258观察细胞核变化,琼脂糖凝胶电泳检测DNA断裂、流式细胞仪检测细胞凋亡率,比较各组间的差异。结果随2,5己二酮浓度增加,细胞存活率下降(P<0.01);荧光显微镜观察有特征性的凋亡细胞核;琼脂糖凝胶电泳有明显的DNAladder;流式细胞仪检测凋亡率随2,5己二酮浓度的增大而增加(P<0.05)。结论一定浓度的2,5己二酮有导致PC12细胞损伤和凋亡的作用。     

苦参碱诱导人喉癌细胞Hep-2凋亡的实验研究

目的 研究苦参碱对人喉癌细胞Hep-2的生长抑制作用及凋亡机制.结果 四甲基噻唑蓝(MTT)法测定苦参碱对细胞的抑制作用,荧光显微镜、DNA琼脂糖凝胶电泳、流式细胞仪技术(FCM)观察细胞周期及凋亡.结果 不同浓度苦参碱对Hep-2细胞有明显抑制作用,且呈时间依赖性及剂量依赖性;FCM检测结果 显示:S期细胞比例及凋亡率增高,G2/M期细胞比例下降,且呈剂量依赖性;形态学发现Hep-2细胞染色质凝聚,核碎裂,凋亡小体形成;DNA琼脂糖凝胶电泳显示典型的梯形条带.结论 苦参碱可能是通过将人喉癌细胞周期阻滞在S期,诱导喉癌细胞凋亡,抑制其增殖,发挥其抗癌功能.     

牛乳铁蛋白素对Jurkat细胞和HFL-I细胞生物学特性的影响

目的形态学观察牛乳铁蛋白素(LfcinB)对Jurkat细胞与人胚肺成纤维(HFL-I)细胞作用的程度,验证LfcinB诱导Jurkat细胞凋亡信号转导通路。方法用荧光显微镜观察Hoechst33258染色LfcinB处理过的Jurkat细胞和正常成纤维细胞,与阴、阳性对照组比较;用DNA断裂琼脂糖凝胶电泳分析LfcinB对Jurkat和HFL-I细胞作用差异;用流式细胞术分析Jurkat细胞早期凋亡和线粒体电势电位状况;Westernblotting研究Jurkat细胞接触LfcinB4、6和8h细胞内caspase-3、caspase-8、caspase-9和胞浆中细胞色素C含量的变化。结果在LfcinB作用Jurkat细胞DNA断裂琼脂糖凝胶电泳图中显示为阶梯状凋亡DNALadder,而LfcinB作用的HFL-I细胞无此现象;在荧光显微镜可以看到LfcinB作用过的Jurkat细胞经Hoechst33258染色细胞核呈致密浓染和HFL-I细胞的细胞核呈均匀染色;流式术分析结果为LfcinB作用Jurkat细胞2、4h的凋亡率分别为11.5%和17.8%,线粒体膜电位下降;caspase-3、caspase-9和细胞色素C的免疫印记分析显示,LfcinB能使Jurkat细胞胞浆中的细胞色素C含量增加,被激活caspase-3、caspase-9在胞浆中逐渐增多,对caspase-8没有影响。结论LfcinB诱导Jurkat细胞凋亡,对正常成纤维细胞没有作用;Jurkat细胞接触LfcinB2h以后细胞内caspase-3、caspase-9和胞浆中细胞色素C的含量累积增加,验证了LfcinB通过依赖caspase家族的细胞内信号通路诱导Jurkat细胞凋亡。     

α-生育酚琥珀酸酯诱导人胃癌SGC-7901细胞凋亡及其作用的分子形式

目的　探讨α- 生育酚琥珀酸酯 (α TOS)诱导人胃癌SGC -790 1细胞凋亡时发挥作用的分子形式。方法　在体外培养的SGC 790 1细胞中 ,分别加入 5、10和 2 0 μg ml的α- TOS ,以 2 0 μg mlα 生育酚 (α- TOH)和1μl/ ml乙醇为对照培养 4 8小时后采用联咪二苯吲哚 (DAPI)染色 ,荧光显微镜下观察细胞形态 ,琼脂糖凝胶电泳检测DNA降解片段 ,并用HPLC法检测细胞内和培养液中α TOS和α- TOH含量。结果　细胞经DAPI染色发现 ,10 μg ml和 2 0 μg mlα TOS处理组细胞核染色体浓集 ,伴有细胞核固缩和核碎片形成。琼脂糖凝胶电泳检测发现 ,上述 2组细胞DNA出现梯形分子条带。在α -TOS处理的细胞内和培养液中HPLC仅检测到α- TOS ,未发现其分解产物α- TOH。结论　α TOS能诱导SGC 790 1细胞凋亡 ,且是以不分解的整体分子形式发挥其诱导凋亡作用 ,与α- TOH的作用无关。     

9-羧酸蒽对人髓性白血病细胞株HL-60凋亡的研究

目的　研究氯通道抑制剂 9-羧酸蒽 ( 9-AC)对人髓性白血病细胞株HL - 6 0的影响 ,并对相关机制进行探讨。方法　体外培养人白血病细胞株HL - 6 0 ,采用透射电子显微镜、DNA琼脂糖凝胶电泳、流式细胞仪等观察9-A对HL - 6 0细胞的作用。结果　在 5× 10 -4 mol/L 9-AC作用 48h后 ,细胞发生明显的改变。电镜下细胞形成典型的凋亡小体。DNA琼脂糖凝胶电泳出现特征性梯形条带。流式细胞仪分析表明 ,实验组HL - 6 0细胞出现明显的亚二倍体峰 -凋亡峰。结论　 9-AC具有明显的诱导白血病细胞HL - 6 0凋亡的作用。     

硫芥诱导淋巴细胞凋亡与细胞周期的关系

目的 探讨硫芥诱导体外培养大鼠脾脏淋巴细胞凋亡及与细胞周期的关系。方法 体外分离培养大鼠脾脏淋巴细胞。以流式细胞仪、琼脂糖凝胶电泳分别检测细胞凋亡，细胞周期，和DNA片段改变。结果 硫芥可诱导淋巴细胞凋亡(P＜0．05)，对细胞周期有明显影响，主要是S期和G2／M期明显降低，引起淋巴细胞生长阻滞在Gl期；流式细胞仪PI染色出现亚二倍体峰(凋亡峰)，其Gl期DNA含量明显增加，S期含量减少；琼脂糖凝胶电泳呈典型的“梯状”带(DNA ladder)。结论 硫芥可抑制体外培养的淋巴细胞由Gl期进入S期，抑制体外培养的淋巴细胞增殖，通过诱导淋巴细胞凋亡实现作用机制。     

羟基喜树碱对肺癌细胞A549抑制作用的研究

目的:研究羟基喜树碱对人肺癌A549细胞的抑制效果,探讨抗癌药物对细胞凋亡与周期的调控作用.方法:CCK-8法测定不同浓度的HCPT对A549细胞的生长抑制作用,AO/EB染色观察细胞生长情况;琼脂糖凝腔电泳验证细胞调亡的特征性DNA条带;用流式细胞仪测定抗癌药物羟基喜树碱对细胞凋亡和细胞周期的影响.结果:CCK-8结果表明不同浓度的HCPT对A549细胞的生长抑制作用不同;琼脂糖凝胶电泳可见调亡细胞DNA的梯状条带;荧光显微镜下观察到经AO/EB染色的典型凋亡细胞;在相同浓度下,随时间的延长细胞的凋亡率也逐渐增加,1μmol/l的HCFT作用于A549细胞对其抑制效果最为明显,细胞凋亡率为32.03%.结论:抗癌药物羟基喜树碱对A549有抑制效果,促进其细胞凋亡,参与细胞周期调控.     

Protective effect of atorvastatin on radiation-induced vascular endothelial cell injury in vitro

Vascular endothelial cells are very sensitive to ionizing radiation, and it is important to develop effective prevent agents and measures in radiation exposure protection. In the present study, the protective effects of atorvastatin on irradiated human umbilical vein endothelial cells (HUVEC) and the possible mechanisms were explored. Cultured HUVEC were treated by atorvastatin at a final concentration of 10 μ mol/ml for 10 minutes, and then irradiated at a dose of 2 Gy or 25 Gy. Twenty-four hours after irradiation, apoptosis of HUVEC was monitored by flow cytometry, and the expression of thrombomodulin (TM) and protein C activation in HUVEC was respectively assessed by flow cytometry and spectrophotometry. After treatment with atorvastatin for 24 h, the rate of cell apoptosis decreased by 6% and 16% in cells irradiated with 2 Gy and 25 Gy, respectively. TM expression increased by 77%, 59%, and 61% in untreated cells, 2 Gy irradiation-treated cells, and 25 Gy irradiation-treated cells, respectively. The protein C levels in 2 Gy and 25 Gy irradiation-treated cells were reduced by 23% and 34% when compared with untreated cells, but up-regulated by 79% and 76% when compared with cells which were irradiated and treated with atorvastatin. In conclusion, these data indicate that atorvastatin exerts protective effects on irradiated HUVEC by reducing apoptosis by up-regulating TM expression and enhancing protein C activation in irradiated HUVEC.     

同型半胱氨酸诱导内皮细胞凋亡及叶酸的拮抗机制———Caspase3及其抑制蛋白c-IAP1和c-IAP2的作用

目的　本研究探讨同型半胱氨酸 (Hcy)致内皮细胞凋亡的途径以及叶酸拮抗Hcy的机制。方法　Hcy、叶酸或二者联合处理人脐静脉内皮细胞 (HUVEC) 2 4小时后 ,用AnnxinV染色加流式细胞术及基因组DNA电泳检测DNAladder了解细胞凋亡状态 ;RT PCR和蛋白质印迹技术检测caspase3、c IAP1和c IAP2的mRNA和蛋白质水平。结果　 0 3mmol L和 3 0mmol L的Hcy均导致HUVEC凋亡 ,Hcy浓度高时凋亡细胞数较高 ,并伴有caspase3表达和活化增强 ,以及c IAP2的mRNA和蛋白质水平降低 ;叶酸可上调c IAP2的表达。结论　Hcy诱导HUVEC凋亡 ,此种作用可能涉及caspase3相关途径。叶酸可促进c IAP 2表达 ,从而部分拮抗Hcy的作用。     

Potential for vaccination against infections caused by Staphylococcus aureus

Surface polysaccharides and proteins from S. aureus which could serve as components of a future subunit vaccine against staphylococcal disease in man and animals have recently been characterized. The majority of bovine mastitis and human clinical isolates of S. aureus produce a thin polysaccharide capsule which probably impairs phagocytosis. Protective immunity to S. aureus infections in laboratory animals has been induced by immunization with polysaccharide, and immune serum promotes phagocytosis of bacteria in vitro. S. aureus expresses several surface-exposed proteins that bind host plasma proteins to the bacterial cell or promote adherence of bacteria to host cells or to tissues. These activities may help bacteria avoid host defences and stimulate adherence and colonization to form foci of infection. In this article the properties of S. aureus surface polysaccharides and proteins are reviewed. Their contribution to virulence and the possibility that they could be used as components of new vaccine to combat mastitis in ruminants and nosocomial infections is discussed.     

抗氧化维生素对氧化低密度脂蛋白作用的主动脉内皮细胞脂质过氧化损伤的影响

为深入探讨抗氧化维生素（维生素Ｅ、维生素Ｃ及β－胡萝卜素）对氧化低密度脂蛋白（ｏｘＬＤＬ）损伤内皮细胞的防治作用及可能机理,我们以体外培养的小牛主动脉内皮细胞为模型、在培养的主动脉内皮细胞中加入不同剂量的抗氧化维生素,共同培养１２ｈ,再与终浓度为０．１ｇ／Ｌ的ｏｘＬＤＬ继续培养２４ｈ,取贴壁细胞及培养液,通过硫代巴比妥酸荧光比色法（ＴＢＡ）和单核细胞（ＨＬ６０）粘附计数法观察不同浓度的抗氧化维生素对ｏｘＬＤＬ损伤的内皮细胞脂质过氧化及单核细胞粘附性的影响。结果表明,抗氧化维生素各组细胞培养液中丙二醛（ＭＤＡ）含量以及内皮细胞粘附的ＨＬ６０细胞数均明显低于ｏｘＬＤＬ组,提示维生素Ｅ、维生素Ｃ及β－胡萝卜素三种抗氧化维生素均可减轻ｏｘＬＤＬ对内皮细胞的脂质过氧化损伤,阻止单核细胞的粘附。这些可能是抗氧化维生素防治动脉粥样硬化的重要机理之一。     

抗氧化维生素对氧化密度脂蛋白作用的主动脉内皮细胞脂质过氧化损伤？…

为深入探讨抗氧化维生素（维生素Ｅ、维生素Ｃ及β－胡萝卜素）对氧化低密度脂蛋白（ｏｘＬＤＬ）损伤内皮细胞的防治作用及可能机理,我们以体外培养的小年主支脉内皮细胞为模型,在培养的主动脉内皮细胞中加入不同剂量的抗氧化维生素,共同培养１２ｈ,再与终浓度为０．１ｇ／Ｌ的ｏｘＬＤＬ继续培养２４ｈ,取贴壁细胞及培养液,通过硫代巴比妥酸荧光比色法（ＴＢＡ）和单核细胞（ＨＬ６０）粘附计数法观察不同浓度的抗氧化维生素     

重度妊娠高血压综合征患者血清诱导的脐血管内皮细胞凋亡失衡与肿瘤坏死因子的关系

目的:探讨重度妊娠高血压综合征(简称妊高征)患者血清对体外培养的脐血管内皮细胞(HUVEC)凋亡和对抑／促凋亡基因Bcl-2／Bax表达的影响以及与肿瘤坏死因子α(TNFα)的关系。方法:体外培养HIJVEC,加入重度妊高征患者血清和TNFα作为处理因素,免疫细胞化学检测Bcl-2／Bax蛋白表达;流式细胞仪做凋亡细胞记数;扫描电镜观察细胞变化。结果:轻重度妊高征患者血清处理后的HUVEC Bcl-2／Bax表达失衡,凋亡细胞数增加,扫描电镜可见经TNFα处理后的内皮细胞变圆,微绒毛消失,密度增高,可见凋亡小体。结论:TNFα可诱导体外培养的脐血管内皮细胞凋亡,并可引起凋亡相关基因Bcl-2／Bax表达失衡,可能是引起妊高征血管内皮细胞损伤的原因之一。     

茶多酚对同型半胱氨酸诱导损伤的人血管内皮细胞纤溶功能的影响

目的研究茶多酚(TP)对同型半胱氨酸(Hcy)损伤的人脐静脉内皮细胞(HUVEC)形态及组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制剂-1(PAI-1)含量的影响。方法将HUVEC分为同时给予TP和Hcy组与先给予Hcy再给予TP组,各组又按TP浓度不同分成若干小组,根据细胞形态变化和ELISA法测定细胞上清液中t-PA和PAI-1的含量变化。结果无论同时给予TP和Hcy组还是先给予Hcy再给予TP组,中浓度(4、8μg/ml)和高浓度(16μg/ml)TP组细胞形态较单纯Hcy组细胞形态规则,立体感增强,胞浆内颗粒减少。ELISA结果显示,单纯Hcy组与正常对照组相比,PAI-1含量增加(P<0.05),含中、高浓度TP组,PAI-1含量较单纯Hcy组降低,且与TP浓度呈剂量依赖性降低(P<0.05),低浓度TP组PAI-1含量与单纯Hcy组差异无显著性;各组t-PA差异均无显著性。结论一定浓度的TP可以恢复Hcy引起的HUVEC细胞形态改变,且可以逆转Hcy引起的PAI-1含量增高的现象。     

黄绿青霉素对人血管内皮细胞凋亡和DNA损伤的作用

目的:观察黄绿青霉素(CIT)对血管内皮细胞凋亡和DNA损伤的作用.方法:体外原代培养人脐静脉内皮细胞,给予浓度分别为1umo1/L、2umol/L、5upmol/L、1Oumol/L的CIT毒素,处理时间为48h.光镜观察细胞生长形态,MMT法检测细胞活性,流式细胞仪检测细胞凋亡情况,单细胞凝胶电泳法分析CIT对内皮...     

High glucose and N ε-(carboxymethyl) lysine bovine serum albumin modulate release of matrix metalloproteinases in cultured human endothelial cells

Background Hyperglycaemia may contribute to endothelial dysfunction. Disturbances in endothelial functions include changes in the extracellular matrix underneath the cells. This may result from altered biosynthesis of matrix molecules or from modified biosynthesis and secretion of enzymes involved in the turnover of extracellular matrix. One important class of such enzymes are the matrix metalloproteinases (MMPs). Aim of the study The aim of this study was to investigate whether the condition of high glucose concentration relevant both to diabetes type 1 and 2 and metabolic syndrome, would affect the synthesis and release of MMPs in human umbilical cord endothelial cells (HUVEC) in vitro. Methods The HUVEC were isolated and cultured in vitro. The cells were exposed to medium with either low glucose (LG, 1 g/l) or high glucose (HG, 4.5 g/l) or the advanced glycation end product (AGE) N ^ε-(carboxymethyl) lysine bovine serum albumin (CML-BSA), at a concentration of 10 μg/ml. The HUVEC-conditioned media were harvested and subjected to gelatin zymography and Western blotting. Results When HUVEC were incubated with HG or CML-BSA under serum free conditions a decreased secretion of pro MMP-2 was observed, both with gelatin zymography and Western blotting. The HUVEC also secreted MMP-9, but at lower levels, and effects of HG treatment were not significant. When HUVEC were stimulated with phorbol 12-myristate 13-acetate (PMA) secretion of pro MMP-2 was not increased, but the activation of pro MMP-2 into lower molecular forms increased, irrespective of culturing in LG, HG or CML-BSA. Conclusion The HUVEC exposed to high glucose or AGE exhibit decreased secretion of MMP-2. These findings may be relevant in understanding the altered turnover of the endothelial extracellular matrix observed in the diabetic state.     

Expression of collagen XVIII mRNA and protein in human umbilical vein and placenta

Endostatin is a potent angiogenic inhibitor that is derived from collagen XVIII by proteolytic cleavage. Localization of collagen XVIII has been reported in the basement membrane of blood vessels. To examine the involvement of collagen XVIII/endostatin during pregnancy, the distribution of collagen XVIII/endostatin protein in human umbilical vein was evaluated by immunohistochemistry. The expression of collagen XVIII/endostatin in cultured human umbilical vein endothelial cells (HUVEC) was also examined by immunocytochemistry and Northern blot analysis. To examine the release of endostatin in vivo and in vitro, concentrations of endostatin in umbilical venous blood and in HUVEC culture medium were determined using an enzyme-linked immunosorbent assay. Collagen XVIII/endostatin protein was localized to endothelial cells and their basement membrane in the umbilical vein. The expression of collagen XVIII mRNA and protein was detected in HUVEC. However, endostatin was not detected in umbilical venous blood or in HUVEC culture medium. The absence of endostatin release and the presence of its parental protein, collagen XVIII, suggest that the cleavage mechanisms of endostatin might be strongly inhibited under the physiological conditions present during pregnancy. It is therefore considered that vasculature in the feto-placental unit is highly angiogenic, even at the time of parturition.