Effect of the heparinoid pentosan polysulphate (SP 54) on the functional properties of cultured bovine aortic endothelial cells

Summary The effect of the heparinoid, pentosan polysulphate (PP) on the proliferative behaviour of cultured bovine endothelial cells (EC) was examined. In addition, the toxicity of the drug towards EC, its influence on prostacyclin production and release, and on cell-associated plasminogen activator activity was determined. At a concentration of 10 g/ml in the culture medium, PP exerted a growth promoting effect on EC. Increased cell numbers were accompanied by increased ³H-thymidine incorporation into cellular DNA compared with controls, however, final density of the cells was not affected. In contrast, at doses of 1 mg/ml the growth of EC was substantially slowed down. This finding did not reflect cell injury as shown by an unaltered release of ⁵¹Cr from the cells. Incubation of PP with EC had no influence on the prostacyclin release from the cells neither on the accumulation of the metabolite in the culture fluid over 24 hours nor on the releasing capacity upon stimulation with arachidonic acid. PP increased the cell-associated plasminogen activator activity in growing cells and counteracted in cultures at final density the inhibitory effect of serum on the intracellular plasminogenactivator activity. Our results suggest that stimulation of the fibrinolytic activity of the endothelium and a growth promoting effect for endothelial cells that may lead to faster coverage of small lesions could contribute to the antithrombotic potency of pentosan polysulphate in vivo.     

Short-termin vivo stability of endothelial-lined polyester elastomer and polytetrafluoroethylene grafts

A fibronectin substrate will significantly enhance the strength of endothelial cell attachment on grafts constructed of polyester elastomer (PE) and polytetrafluoroethylene (e-PTFE). This experiment was undertaken to determine the short-termin vivo stability of endothellum on these fibronectin coated surfaces. Eight mongrel dogs underwent bilateral carotid artery replacement with both graft materlals. All grafts were inoculated with 2,000 cells/mm² using cultured autogenous venous endothelium labelled with Indium-111-oxine. The Indium-111 label in the grafts was measured immediately prior to implantation, after 1 hour ofin vivo perfusion, and at explantation after 24 hours. The percentage of inoculated cells attached to the grafts before perfusion was simillar for both materials, 93.3±3.0% versus 92.2±7.2%, for PE and e-PTFE respectively. All grafts were patent at one hour after implantation. PE grafts were found to have 93.8±3.9 % of the attached cells present at one hour while e-PTFE grafts had only 54.5 ± 10.8 % remaining, p<.001. After 24 hours, 5/8 (62.5%) e-PTFE grafts and 2/8 (25.0 %) PE grafts remained patent, p=.13. Of the patent grafts however, endothelial cell retention was still superior on the PE grafts with 78.0±0.6% of the attached cells remaining compared to only 24.5±6.1% on e-PTFE, p<.001. Occluded PE grafts had fewer cells remaining at 24 hours than patent ones, 78.0±0.6% versus 31.1±32.8%, respectively, p=.13. Histologically, patent PE grafts demonstrated nearly confluent endothelial monolayers while e-PTFE had patches of endothelial cells surrounded by, a platelet-fibrin carpet. We conclude that short-term patency appears to be determined by the extent of endothelial retention on PE but not e-PTFE.     

内皮细胞型NO合成酶基因4a／4b多态性与糖尿病肾病的相关性

目的 探讨内皮细胞型NO合成酶（eNOS)基因第4内含子一个27bp的可变数目串联重复序列多态性（VNTRs,4a/4b）与中国北方汉族人2型糖尿病（DM）合并肾病（DN）的相关性。方法 运用聚合酶链反应（PCR）结合高浓度琼脂糖凝胶电泳分离和DNA测序技术,检测病程超过10年的2型DM患者（143例）和健康人（N）（85例）的eNOS基因第4内含子27bp的VNTRs(4a/4b)多态性的基因型,比较各组间的等位基因频率与基因型频率。结果 ①DM组的4a等位基因及4a4b基因型频率与N组差异无显著性（P＞0．05）。②DN＋组4a等位基因及4a4b基因型频率显著高于糖尿病非肾病患者（P＜0．05）。③SBP,HA1c,TG,TC和eNOS基因第4内含子4a/4b多态均与糖尿病肾病有关。结论 eNOS基因第4内含子4a等位基因可能是中国人2型糖尿病合并肾病的独立危险因素。     

血管内皮生长因子在妊高征胎盘中的表达研究

目的观察血管内皮生长因子(VEGF)在妊高征(PIH)胎盘中的表达情况.方法用免疫组织化学法,检测30例正常晚孕胎盘(对照组)和34例妊高征胎盘(妊高征组)中的VEGF表达水平,并作计算机图像分析,测定各组标本的阳性染色光度值.结果VEGF在正常晚孕胎盘和妊高征胎盘中均有表达,其分布基本一致,主要在滋养细胞、血管内皮及绒毛间质.计算机图像分析结果示,对照组VEGF阳性染色光度为0.23780±0.00434,妊高征组VEGF阳性染色光度为0.20688±0.01530,其中轻度0.22603±0.00828,中度0.20364±0.00365,重度0.19151±0.00441,妊高征组中VEGF表达明显低于对照组P＜0.01.且随妊高征病情的加重,VEGFF表达水平呈下降趋势.结论妊高征胎盘中VEGF表达水平降低可能与胎盘血管生成减少及胎盘滋养细胞侵入异常有关,在妊高征的发病中起重要作用.     

血管内皮细胞生长因子抗体对胶质瘤生长的影响

探讨血管内皮细胞生长因子(vascularendothelialgrowthfctor,VEGF)对胶质瘤生长的抑制作用。方法应用vEGF抗体作用于C6胶质瘤细胞动物肿瘤模型,观察其抑瘤作用;应用SABC免疫组化技术检测体内生长胶质瘤中微血管密度。结果VEGF抗体对体内生长的胶质瘤有显著抑制作用且呈剂量依赖关系,押瘤率可达82.8％(P<0.01)。经VEGF抗体治疗的胶质瘤中微血管密度较对照组降低(P<0.01)。结论vEGF抗体通过抑制血管生成而抑制胶质瘤生长。     

藤黄酸通过YAP信号通路发挥对高糖诱导的内皮损伤的保护作用

目的 探讨藤黄酸在高糖诱导的内皮损伤中的保护作用及可能的作用机制。方法 人脐静脉内皮细胞（HUVEC）分5组,对照组给与低糖培养基培养,模型组和藤黄酸低剂量组、中剂量组和高剂量组均给与40mmol/L葡萄糖培养基培养,藤黄酸各给药组分别给与0.2μM、0.4μM、0.8μM藤黄酸处理,MTT检测各组细胞活力,流式细胞术检测各组凋亡,WB检测凋亡蛋白Cl-cas-3和Cl-cas-9表达,收集各组细胞上清液,检测氧化应激指标:ROS、MDA、NO以及粘附分子ICAM-1、VCAM-1水平,WB检测YAP信号通路蛋白总YAP（t-YAP）蛋白和细胞核中YAP（n-YAP）蛋白表达量。在藤黄酸处理基础上,在HUVEC细胞中过表达YAP,MTT检测细胞活力,WB检测t-YAP和n-YAP蛋白表达。结果 与对照组比较,模型组及各给药组HUVEC细胞活性明显降低、凋亡率显著增加,凋亡蛋白Cl-cas-3和Cl-cas-9表达增加,细胞中ROS、MDA水平增加,NO水平降低,ICAM-1、VCAM-1水平增加,t-YAP和n-YAP蛋白表达增加（P<0.05）,与模型组比较,藤黄酸各剂量组细胞活力显著增加、凋亡率显著降低,凋亡蛋白Cl-cas-3和Cl-cas-9表达降低,细胞中ROS、MDA水平降低,NO水平升高,ICAM-1、VCAM-1水平降低,t-YAP和n-YAP蛋白表达降低,差异均有统计学意义（P<0.05）。藤黄酸+YAP组细胞活性显著低于藤黄酸组（P<0.05）,t-YAP和n-YAP蛋白显著高于藤黄酸组（P<0.05）。结论 藤黄酸可以抑制高糖诱导的HUVEC凋亡,增强细胞活力,减轻氧化应激损伤和细胞粘附,对高糖诱导的内皮损伤发挥保护作用,机制可能与抑制YAP信号通路激活有关。     

Human monocyte-derived hemangioma-like endothelial cells: evidence from an in vitro study

BACKGROUNDS: Hemangiomas are highly prevalent in newborns and infants and can lead to severe complications. However, the pathogenesis of hemangiomas is still unknown. This study was designed to examine the potential of human monocytes to differentiate into hemangioma endothelial cells. METHODS: Purified monocytes from adult human peripheral blood were cultured under a conditional culture environment supplemented with basic fibroblast growth factor and vascular endothelial growth factor. Cells cultured for 2 weeks were subjected to histological and immunochemical examinations in order to determine the expression of specific markers for hemangioma endothelial cells. RESULTS: Monocytes cultured for 2 weeks in angiogenic medium expressed human erythrocyte-type glucose transporter protein, FcgammaRII, and several other endothelial markers, all of which are deemed specific markers for hemangioma endothelial cells. However, neither CD133 nor alpha smooth muscle actin was detected in our monocyte culture. CONCLUSION: Our data suggested that monocytes are capable of differentiating into hemangioma endothelial cells under the angiogenic stimulation from microenvironment of proliferative hemangioma.     

年龄对健康人红细胞与内皮细胞粘附的影响

本文用流槽系统，定量地研究年龄对健康人红细胞与培养的人脐静脉内皮细胞粘附的影响。在本研究所选用的两个年龄阶段，其结果显示：①红细胞自身特性的改变对粘附的数目没有明显的影响，但随着年龄的增加粘附的强度增大；②在自体血浆存在时，随着年龄的增加红细胞与内皮细胞的粘附增强。这可能与心脑血管病如心肌梗塞、脑血栓形成等多发生在４０岁以上的中老年人有关。     

Recent advances in understanding the pathogenesis of the hemolytic uremic syndromes

One of the requirements for an agent to cause hemolytic uremic syndrome (HUS) is its ability to injure endothelial cells. Shiga-like toxin (SLT) can do this. SLT is produced byEscherichia coli andShigella dysenteriae serotype 1; both have been implicated as causes of typical HUS. Endothelial cells have receptors (GB₃) for SLT and the toxin can inhibit eukaryotic protein synthesis, thereby causing cell death. Glomerular endothelial cell injury or death results in a decreased glomerular filtration rate and many of the perturbations seen in HUS. It is no longer certain that hemolysis is the result of a microangiopathy. Cell injury results in release of von Willebrand multimers; if these are ultra-large, thrombosis may ensue. There is also increasing evidence that neutrophils have a role in the pathogenesis of typical HUS.Streptococcus pneumoniae can also cause HUS and care must be taken to avoid giving plasma to patients withS. pneumoniae-associated HUS. There is compelling evidence that types of HUS are inherited by autosomal recessive and autosomal dominant modes. Patients with autosomal recessive HUS may have recurrent episodes. Mortality and morbidity rates are high for the inherited forms.     

黄体酮对兔离体主动脉平滑肌张力的影响

目的　观察黄体酮对KCl去极化引起的兔离体主动脉肌条收缩作用的影响 ,并探讨其作用与内皮细胞的关系。方法　制备家兔离体主动脉平滑肌条 ,置于灌流肌槽中 ,记录肌条的张力变化。结果　黄体酮 (5、5 0和 10 0 μmol·L- 1)使KCl量效曲线明显右移 ,最大反应压低 ,KCl的EC50 由对照 (36.4± 19.7)mmol·L- 1依次变为 (4 0 .3± 19.6)、(4 3.4± 2 0 .9)和 (5 9.0± 2 0 .1)mmol·L- 1(r =0 .94 ,P <0 .0 5 ) ;83.3μmol·L- 1黄体酮使KCl 2 5 .1mmol·L- 1预收缩胸主动脉肌条明显舒张 (P <0 .0 0 1) ;去内皮后 ,此舒张作用明显减弱。结论　黄体酮可使兔胸主动脉血管平滑肌条舒张 ,其作用可能是通过抑制血管平滑肌细胞膜上的电压依赖性钙通道 ,并与内皮细胞存在有关