Adhesion-Preventive Biomaterials

术后组织粘连有时会引起严重的问题。因此，已经尝试了几种技术来防止组织粘连，例如，通过施加聚合物的粘性水溶液来保护组织。我们的方法是在可能发生粘连的组织之间插入生物可吸收片。为此，从D，L-丙交酯和己内酯的共聚物制备柔软的柔性片材<epsilon>。使己内酯单体共聚以降低片材的软化温度。除了柔性之外，片材的生物降解速率也很重要。65：35和88：12（摩尔比）的L-丙交酯-己内酯共聚物在37 ℃下浸入PBS中分别在20和24周后显示100%的重量损失。为了检查我们的生物可吸收片材在体内的有效性，将同一只狗的心包和壁胸膜部分消融，并将尺寸为4 × 8 cm 2的生物可吸收片材（D，L-丙交酯-己内酯80：20，共聚物）固定在其间。术后3个月复查无炎症及周围组织粘连症状。此外，进行了一项研究，以检查通过使用含有弹性蛋白酶的聚-D，L-丙交酯片来预防腰椎椎板切除术后瘢痕形成的可能性，所述弹性蛋白酶将防止胶原纤维的生长。对兔子的实验表明，含有弹性蛋白酶的片材比不含弹性蛋白酶的片材更有效地抑制瘢痕形成。

Postoperative adhesion of tissues sometimes cause severe problems. Therefore, several techniques have been attempted to prevent tissue adhesion, for instance, by applying viscous aqueous solutions of polymer to protect the tissue. Our method is to insert a bioabsorbable sheet between the tissues where adhesion will possibly take place. For this purpose, a soft, flexible sheet was prepared from a copolymer of D,L-lactide and <epsilon> -caprolactone. The caprolactone monomer was copolymerized so as to reduce the softening temperature of the sheet. The biodegradation rate of the sheet is important in addition to the flexibility. L-Lactide-caprolactone copolymers of 65:35 and 88:12 (by mole) showed 100 % weight loss after 20 and 24 weeks, respectively, when immersed in PBS at 37 C. To examine the effectiveness of our bioabsorbable sheet in vivo, the pericardium and the parietal pleura of the same dog was partially ablated and the bioabsorbable sheet (D,L-lactide-caprolactone 80:20, copolymer) with a size of 4 x 8 <cm^2> was fixed in between. Inspection at 3rd month postoperation revealed no inflammation and no symptom of adhesion of the surrounding tissues. Also, a study was undertaken to examine the possibility of prevention of the scar formation after lumbar laminectomy by use of poly-D,L-lactide sheet containing elastase that would prevent the growth of collagen fibrils. Experiments on rabbits showed that the sheet containing elastase more effectively suppressed the scar formation than the sheet without elastase.