Development of a vascular prosthesis coated with bioabsorbable materials free from pathological proteins

研制了一种生物可吸收涂层的织物血管假体。本项目的目的是获得一种无牛海绵状脑病的涂层织物血管假体。首先，我们寻找了一种合适的涂层材料。经过一些检查，我们选择了非病理性的无蛋白物质，如纤维素、超高分子透明质酸、聚乙二醇、聚乙烯醇及其底物。我们的基础实验表明，最适合于此目的的材料是羧甲基纤维素(CMC)。其次，我们所做的努力是如何将材料溶解在织物假体上。我们检查了甲醛、戊二醛和六亚甲基二异氰酸酯等化学试剂。均表现出细胞毒性。经过长期洗涤，用这些化学试剂交联的材料显示出细胞毒性。根据这一结果，我们放弃了使用这些化学试剂。最后，我们采用了物理方法，如有机玻璃辐照、紫外线辐照和电子束辐照。但它们都对纤维有足够的损伤，因此我们采用了热交联法。这是一种简单的方法，但没有显示任何毒性反应。第三，我们努力为涂层创造了最好的织物血管假体矩阵。为此，我们研制了一种由超细聚酯纤维制成的假体。这些超细纤维可以非常迅速地捕获涂层物质。最后，在这些基础实验的基础上，研制出了一种由超细涤纶纤维包覆CMC制成的织物假体。CMC不溶于热交联剂。我们将制造的假体植入狗的胸降主动脉。移植物达到了预期的效果。我们目前正在对这一体内实验进行观察，进行长期分析。

A fabric vascular prosthesis coated with bioabsorbable mateiraal was developed. This project was aimed to obtain a coated fabric vascular prosthesis free from bovine spongious encepharopathy. At first, we searched a suitable material for the coating. After some examinations, we selected non-pathological protein free substances, such as cellulose, extremely high molecule hyaluronic acid, polyethylene glycol, polyvinyl alcohol, and their substrates. Our basic experiments showed that the most suitable material for this purpose was carbomethyl cellulose (CMC). Secondly, we made efforts was how to insolubilize the materials on a fabric prosthesis. We checked chemical reagents such as formaldehyde, glutarardehyde and hexamethylene diisocyanate. All of them showed cytotoxicity. After long-term washing, the materials crosslinked with these chemical reagents showed cytotoxicity. From this results, we gave up to use these cehmical reagent.Finally, we adpoted physical methos such as gannma-ray irradiation, ultraviolet irradiation., and electron beam irradiation. But all of them showed adequate damages to the fabric fibers.Therefore, we used heat-cross-linking method. This was a simple method, but it did not show any citotoxic reacton. Thirdly, we made effort to create a best matrilx of the fabric vascular prosthesis for the coating.. For this purpose, we developed a prosthesis fabricated with ultrafine polyester fibers. These ultrafine fibers can trap the coated substance very firmaly. Finally, with these basic experiments, a fabric prosthesis made of ultrafine polyester fibers which was coated with CMC. The CMC was insolubilized by heat cross-linking. We implanted the created prostheses into the thoracic descending aortae of dogs. The graft showed expected results. We are now underway to observe this in vivo experiment for long-term analysis.