Development of biocompatible synthetic materials for tracheal prosthesis

(1)我们用长型人工气管（长5cm）对犬气管进行了环周气管置换术。气管假体由Marlex补片（聚丙烯）组成，用连续聚丙烯螺旋增强，并涂有猪胶原蛋白。然而，许多狗遭受局部感染，由于受损的分泌运输，我们不能得到长期的生存。(2)为了促进术后分泌物的运输和保护假体免受局部感染，我们在使用与（1）相同的假体进行气管重建时，暂时将硅胶管插入假体管腔。然后，所有植入的假体都被宿主完全纳入，没有局部感染，因此，我们的假体被证明能够耐受人类手术。(3)考虑到临床应用的需要，我们进行了人工气管在高张力（900- 1000 gf）下的闭合实验。这证明了我们的假体在使用如（2）中的内部硅胶管时，即使在高张力下也没有吻合不足。(4)我们自制了生物可吸收的聚乙醇酸（PGA）补片，并进行了修补犬气管窗缺损的实验。结果表明，PGA补片修复区的伤口愈合情况优于聚丙烯补片，聚丙烯补片是不可吸收的。显示出比聚丙烯网片更好的伤口愈合过程，聚丙烯网片不可吸收。(5)我们研制了一种新型的热形状记忆钛镍合金气道支架，并进行了动物实验。该支架可用于治疗人工气管重建后管腔狭窄，也可用于治疗气管支气管软化。

(1) We performed circumferential tracheal replacement of dog's trachea using long-type tracheal prosthesis (5 cm in length ). The tracheal prosthesis consists of Marlex mesh (polypropylene) reinforced with a continuous polypropylene spiral and it is grafted coated with pig collagen. However, many dogs suffered from local infection due to impaired secretory transportation and we could not get long-term survivors. (2) In order to promote secretory transportation after surgery and protect the prosthesis from local infection , we temporarily inserted silicone tube into the lumen of the prosthesis when we performed tracheal reconstruction using the same prosthesis as in (1). Then, all the prostheses implanted were completely incorporated by the host without local infection, and therefore, our prosthesis proved to be able to tolerate human surgery.(3) Considering clinical application, we performed experiments of anastomosing our tracheal prosthesis under a high tension (900-1000gf). It proved that our prosthesis was fixed without anastomosis insufficiency even under a high tension when the internal silicone tube was used as in (2).(4) We originally made polyglycolic acid (PGA) mesh, which was bioabsorbable, and performed experiments of repairing window defects of dogs' tracheae using this mesh. It proved that the area repaired with PGA-mesh showed better wound-healing process than that with polypropylene mesh, which was non-absorbable. showed better wound-healing process than that with polypropylene mesh, which was non-absorbable.(5) We made a novel intraluminal airway stent from thermal shape memory Ti-Ni alloy, and performed animal experiments. This stent seemed to be useful for measures to the luminal stenosis of the tracheal prosthesis after reconstruction, and it also seemed to be helpful for the treatment of tracheo-bronchial malacia.