Reasearch on pathogenesis and prevention of small caliber prosthetic occlusions

小口径假体咬合的发病机制及预防研究

基本信息

批准号：
05404043
负责人：
MISHIMA Yoshio
金额：
$ 17.79万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (A)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1995
项目状态：
已结题

项目摘要

The aim of this research is to develop new small-caliber prosthesis with long patency, enabling clinical application, and elucidate etiology of graft failures, including neointimal hyperplasia, and its prevention. Dacron grafts, 2mm in diameter and 2cm in length, coated with mixing solution of excellent anti-thrombogenic substance, 2-methacryl-oxyethyl phosphoryl-choline (MPC) polymer and segmented polyurethane (SPU), were implanted in the cervical artery of rats. In the control group, the internal lumen of the graft was covered with red thrombi 90 minutes after implantation and all grafts were occluded within 3 days. On the other hand, MPC grafts had no adhesion of thrombus 5 days after implantation, and its inner surface was covered with thin fibrin-like membrane one week after implantation. After 2 months, smooth neointima was observed, and its early patency was excellent. These results indicate the MPC grafts have possibilities of a clinical application with long patency after adding more sufficient anchoring of neointima against the grafts. Neointimal hyperplasia was significantly suppressed by administration of anti-PDGF drug and its development was significantly differed among various kinds of ePTFE grafts. These results showed pharmacological intervention and reforming structures of grafts may improve long-term patency. Clinically, immunohistochemical studies of occluded graft's anastomosis demonstrated that neointimal denudution is a new factor contributing to late graft failure in addition to neointimal hyperplasia.

这项研究的目的是开发新的小口径假体，具有长时间的通畅性，可以实现临床应用，并阐明了移植失败的病因，包括新的增生及其预防。将抗直径2mm和2厘米长的DACRON移植物植入大鼠的cervical静脉中。在对照组中，植入后90分钟，移植物的内腔被红色血栓覆盖，并在3天内遮住了所有移植物。另一方面，植入后5天的MPC移植物没有血栓的粘附，其内表面植入后一周被纤维蛋白样膜覆盖。两个月后，观察到光滑的新内膜，其早期通畅非常出色。这些结果表明，MPC移植物具有临床应用的可能性，并在对移植物上增加了足够的新内膜锚固后具有长时间的通畅性。抗PDGF药物的给药可显着抑制新的增生，并且在各种EPTFE移植物中其发育显着差异。这些结果表明，嫁接的药理干预和改革结构可以改善长期通畅。在临床上，对闭塞移植物的吻合术的免疫组织化学研究表明，新内膜裸是一个新的因素，这是导致晚期移植物衰竭的新因素，除了新的增生。