内皮化小口径人工血管的研究

目的 探讨成人大隐静脉内皮细胞(HSVECs)种植到人工血管内表面的可行性.方法 酶消化法获取成人大隐静脉内皮细胞,在体外扩增培养13～15 d,将扩增培养的内皮细胞种植于纤维蛋白胶预衬的聚四氟乙烯(ePTFE)人工血管内表面,继续体外培养9～12 d.在不同的时间点,分别剪取部分内皮化的人工血管,行荧光显微镜和扫描电镜检查.结果 内皮细胞种植于人工血管后,扫描电镜下可见细胞在血管表面黏附、生长、增殖.平均孵育12 d后,人工血管腔面见一层均匀的基质,其表面有内皮细胞单层,内皮细胞排列紧密,呈梭形.结论 成人大隐静脉内皮细胞可以种植到人工血管,在体外增殖形成内皮细胞单层,达到内皮化的效果.     

小口径脱细胞基质人工血管移植的研究

目的 探讨脱细胞基质( DCM)人工血管用于小口径血管移植的可行性.方法 40条雄性杂种犬随机分为DCM、膨体聚四氟乙烯(ePTFE)人工血管及自体颈外静脉3组行右颈总动脉置换术,彩超监测移植物通畅率.术后4、8周活体取材,标本行苏木素-伊红(HE)、免疫组织化学染色及扫描电镜检查.结果 3组移植物1周通畅率(75.0％、64.3％、100.0％)差异无统计学意义(P＞0.05);自体颈外静脉组4、8周通畅率( 100.0％、88.9％)优于DCM组(56.3％、26.7％)及ePTFE组(57.1％、23.1％,P＜0.05),后两组差异无统计学意义(P＞0.05).DCM人工血管4、8周血栓形成面积小于ePTFE人工血管,吻合口内膜内皮化程度高于后者.结论 小口径DCM人工血管在抑制血栓形成及加快内皮化方面优于ePTFE人工血管.     

小口径人工血管肠腔静脉搭桥治疗门脉高压

小口径人工血管肠腔静脉间搭桥限制性分流术治疗门脉高压症，手术操作简便、脑病发生率低，且可应用于急症手术。[第一段]     

基因工程内皮细胞种植人工血管的研究进展

自体和非自体的生物血管不能满足临床血管外科的需要。使用理化方法或单纯种植内皮细胞的方法处理人工血管因腔内血栓形成而效果小理想。为了增加人工血管的抗血栓活性，利用基因工程的方法对内皮细胞进行改造，可使其获得稳定表达抗凝血因子的能力。用这种基因工程改造的内皮细胞种植于人工血管，有可能获得较理想的效果。而最终要获得理想的血管移植物，尚有许多需要解决的问题。     

层层自组装肝素/胶原复合涂层聚四氟乙烯小口径人工血管的研究

目的 观察层层自组装肝素/胶原复合涂层聚四氟乙烯小口径人工血管片的抗凝血性能和血液相容性.方法 实验分为复合人工血管片组和普通人工血管片组.采用层层静电组装的方法将带负电的肝素与带正电的胶原交替涂覆到聚四氟乙烯小口径人工血管片上,制备成复合人工血管片.参照IS010993-4及GB/TI6886标准中实验方法行血小板黏附实验、溶血实验及血浆复钙时间实验检测.结果 扫面电镜照片可以观察到普通人工血管片表面有大量血小板黏附,血小板呈扁平状贴覆在材料表面,复合血管片组表面有少量血小板贴覆(2.5±2.4比28.5±4.8,P＜0.05);普通血管片溶血率0.63％,复合血管片溶血率1.27％,均＜5％,且两者差异无统计学意义(P＞0.05);普通血管片血浆复钙时间为8.5 min,复合血管片观察至30 min未见纤维蛋白丝.结论 层层自组装肝素/胶原复合涂层聚四氟乙烯小口径人工血管片具有良好的抗凝血性能及血液相容性.     

基因转染内皮细胞衬里人工血管的研究进展

目的：讨论使用外源性抗凝基因修饰内皮细胞后衬里人工血管，使人工血管局部抗凝活性提高以及对内皮细胞其他生物活性的影响等。方法：复习近几年的相关文献，作综述报道。结果：内皮细胞在转染纤溶酶原激活物(t-PA、u-PA、Urokinase)、血栓调节蛋白(TM)和水蛭素(hirudin)等基因后，均使局部血管的抗凝活性增高，但同时也导致内皮细胞粘附性、增殖功能下降。结论：外源性基因能使内皮细胞预衬的人工血管抗凝活性提高，但仍需进行深入研究。     

小口径人工血管内皮化临床研究现状

冠心病、外周动脉闭塞性疾病、慢性肾功能衰竭建立血液透析通路以及小儿心血管疾病等，这些疾病大多需要小口径血管（直径〈6mm）行动脉移植手术。目前临床上已用的小口径血管移植物包括自体大隐静脉或乳内动脉、涤纶（Dacron）和膨体聚四氟乙烯（ePTFE）人工血管等。自体静脉或动脉移植后虽然能取得较满意的临床疗效，但是因来源有限和供区牺牲大而应用有所限制。在需要行动脉移植手术的患者中，30％以上缺乏适当的自体静脉或动脉移植物。常用的Dacron和ePTFE人工血管在高速血流、低阻力的大、中动脉重建中已取得满意的疗效，     

人工血管内皮化的研究进展

人工血管内皮化的研究进展潘明新综述杨继震何红兵审校作者单位：５１０２８２第一军医大学珠江医院普外科血管病研究室众所周知，人工血管置换病变的静脉和口径小于６ｍｍ的动脉，通畅率十分低下。这与人工血管的内表面难以自发形成抗血栓形成的内皮细胞衬里有关。理论上...     

微血管内皮细胞与人工血管内皮化（综述）

人工血管的应用日趋广泛，如何实现其内皮化是应用的关健。人工血管内皮化的效果决定于三个因素：种植的细胞数、细胞贴壁率、贴壁细胞抗切应力能力。为此，人们进行了内皮细胞获取、培养增殖、微血管内皮细胞获取的研究，尝试了从低密度种植、高密度种植、铺植到离体衬里的一系列内皮化方法，确实了人工血管内皮化的研究的方向：寻求可靠、丰富、方便的细胞来源，建立完善的离体衬里内皮化方法。     

人工血管内皮化的研究现状

工血管完整内皮单层的缺乏是导致新内膜增生、血栓形成和感染的主要刺激,因此,人工血管内皮化已成为目前研究的热点,并在许多方面取得了成绩,但是,仍存在许多问题有待解决。     

Cyanoacrylate for Wound Closure in Prosthetic Vascular Graft Surgery to Prevent Infections Through Contamination

Purpose Prosthetic vascular graft infection (PVGI) still occurs at an unacceptably high rate, despite the many measures that have proven effective against infection. The major cause of PVGI is perioperative contamination, which usually occurs before a histological barrier is completed and may threaten graft viability. We assessed the efficacy of cyanoacrylate as a tissue adhesive and barrier against early contamination through the skin. Method A 1 × 0.5-cm Dacron graft was placed subcutaneously under sterile conditions in 16 Sprague-Dawley rats. The skin was closed with polypropylene sutures in eight rats (group A) and with N-butyl 2-cyanoacrylate in eight rats (group B). The closed incisions were then contaminated with 75 × 10⁶ cfu/ml methicillin-sensitive Staphylococcus aureus. Microbiological and histopathological assessments were done 7 days later, after the rats were killed. Results All of the graft cultures from group A (8/8) were positive for S. aureus whereas all of those from group B (0/8) were negative. This difference was significant (p < 0.001). Histological examination revealed denser inflammatory cell infiltration in group A than in group B. Conclusions Maintaining skin integrity after closure is of the utmost importance because contamination during the first hours of the procedure may cause PVGI. Cyanoacrylate seems to be a promising molecule not only because of its bacteriostatic effects, but also because it seals the barrier effectively and immediately.     

人工血管环代成形环治疗三尖瓣关闭不全56例

目的探讨以人工血管环代替成形环治疗三尖瓣关闭不全的临床效果。方法回顾性分析第二军医大学长海医院2000年7月至2010年7月收治三尖瓣关闭不全56例患者的临床资料,其中男24例,女32例;年龄14～73(45.7±21.8)岁;均经心脏彩色多普勒超声心动图明确诊断为三尖瓣中度至大量反流(瞬时反流量>6 ml),其中风湿性心脏瓣膜病47例,先天性心脏病三尖瓣下移畸形9例。均采用人工血管环代替成形环治疗三尖瓣关闭不全。结果全组患者无早期死亡。术后1个月心脏超声心动图提示无三尖瓣关闭不全或轻度关闭不全,发生并发症3例,其中术后呼吸功能衰竭1例,肾功能不全1例,开胸止血1例。远期随访48例,平均随访3.8(1.0～9.5)年,无晚期死亡,发生抗凝并发症(脑梗死)1例;心功能分级(NYHA):Ⅰ级16例,Ⅱ级26例,Ⅲ级6例。随访期间超声心动图检查提示:三尖瓣无关闭不全36例,轻度关闭不全10例,中度关闭不全2例,无严重并发症。结论人工血管环代替成形环治疗三尖瓣关闭不全可以取得较满意的早期和中期的临床疗效,可作为治疗三尖瓣关闭不全的手术方法之一。     

人工瓣膜心内膜炎

人工瓣膜心内膜炎(prosthetic valve endocarditis,PVE)是心脏瓣膜置换术后一种严重的并发症。近半个世纪以来,PVE的微生物学、病理生理学、临床表现以及诊疗手段等诸方面都发生了显著的变化,人们对其发病机制也有了更进一步的认识。我们拟就PVE的诊断治疗等各个方面作一整体性的综述。     

内皮细胞衬里人工血管静脉旁路移植10例

为进一步证实内皮细胞衬里人工血管的临床效果,报告临床应用１０例的长期随访。方法,本组１０例布加综合征病人,行腔房转流术６例,肠房转流术２例,肠颈转流术和肠腔转 流术各１例。应用人工血管内径１４ｍｍ,长８－３０ｃｍ,其中针织涤纶２根,编织涤纶７根,带外支持环ＰＴＦＥ１根。     

Acellular Endocardium as a Novel Biomaterial for the Intima of Tissue‐Engineered Small‐Caliber Vascular Grafts

We aimed to investigate whether acellular endocardium can be used as a useful biomaterial for the intima of engineered small‐caliber vascular grafts. Fresh endocardium was harvested from the swine left atrium and was decellularized by digestion with the decellularization solution of Triton X‐100 and SDS containing DNase I and RNase A. Surface morphological characteristics and Young's modulus were evaluated. To analyze the effect of mechanical characteristics on cell adhesion, the decellularized endocardium was stiffened with 2.5% glutaraldehyde. Small‐caliber vascular grafts were constructed using decellularized endocardium treated with or without glutaraldehyde as the intima. CD34+ cells were seeded onto the luminal surface of the vascular grafts and linked to bioreactors that simulate a pulsatile blood stream. Acellular endocardium had distinct surface morphological characteristics, which were quite different from those of other materials. The compliance of acellular endocardium was higher than that of other materials tested by Young's modulus. CD34+ cells formed a monolayer structure and adhered to the inner face of the acellular endocardium. The glutaraldehyde treatment stiffened the acellular endocardium but had little impact on the surface morphological characteristics or static adhesiveness of the cells. Data from the bioreactor study showed that the detachment of the cells from the surface of glutaraldehyde‐treated acellular endocardium increased dramatically when the pressure was equal or higher than 40 mm Hg, while the cells on the untreated acellular endocardium remained well and formed confluent monolayers and tight junctions under the same pressure. Acellular endocardium has distinct structures and mechanical characteristics that are beneficial for CD34+ cell adhesion and retention under dynamic fluid perfusion. Thus, it can be used as a useful biomaterial for the construction of the intima of engineered small‐caliber vascular grafts.     

Replacement of the Canine Inferior Vena Cava with a Seeded Graft

The patency and microscopic findings of gelatin-coated Dacron grafts seeded with endothelial cells and implanted into the inferior vena cava of dogs was evaluated. A total of 25 mongrel dogs were divided into four experimental groups according to whether or not an antiplatelet agent was administered and a seeded or nonseeded graft was implanted. In the groups not given antiplatelet therapy that were implanted with a nonseeded graft, occlusion of the graft occurred soon after surgery. In contrast, in the majority of animals implanted with a seeded graft and given antiplatelet therapy, graft patency was evident for up to 4 weeks postoperatively. In the latter animals, scanning electron microscopy 4 weeks after surgery showed the formation of confluent endothelial-like cells within 5 mm from the anastomosis, as well as insular endothelial-like cells in the central part of the graft. The simple centrifugal seeding method enables endothelial-like cells to adhere to grafts, suggesting that it may be useful in venous replacement. Received: October 18, 1999 / Accepted: November 20, 2000     

Multidisciplinary Treatment Approach for Prosthetic Vascular Graft Infection in the Thoracic Aortic Area

Prosthetic vascular graft infection in the thoracic aortic area is a rare but serious complication. Adequate management of the complication is essential to increase the chance of success of open surgery. While surgical site infection is suggested as the root cause of the complication, it is also related to decreased host tolerance, especially as found in elderly patients. The handling of prosthetic vascular graft infection has been widely discussed to date. This paper mainly provides a summary of literature reports published within the past 5 years to discuss issues related to multidisciplinary treatment approaches, including surgical site infection, timing of onset, diagnostic methods, causative pathogens, auxiliary diagnostic methods, antibiotic treatment, anti-infective structures of vascular prostheses, surgical treatment, treatment strategy against infectious aortic aneurysms, future surgical treatment, postoperative systemic therapy, and antimicrobial stewardship. A thorough understanding of these issues will enable us to prevent prosthetic vascular graft infection in the thoracic aortic area as far as possible. In the event of its occurrence, the early introduction of appropriate treatment is expected to cure the disease without worsening of the underlying pathological condition.