兔体内细菌对人工心脏瓣膜的粘附及清除研究

目的探讨细菌在兔体内对人工心脏瓣膜材料的粘附情况及机体对细菌的清除能力。方法将H-胸腺嘧啶3脱氧核苷H-TDR标记的表皮葡萄球菌菌液等量分别与人工心脏瓣膜材料涤纶、热解碳、聚四氟乙烯植入日本长耳白3兔双侧腹膜后间隙,观察术后1、3、5、7天细菌在体内对不同材料的粘附。将球菌在体外粘附于不同人工心脏瓣膜材料,植入腹膜后间隙,观察和比较不同时间兔对已粘附在不同材料上球菌的清除能力。将人工心脏瓣膜材料植入腹膜腔,同时经静脉注入表皮葡萄球菌菌液造成菌血症或败血症,比较细菌对腹膜腔内不同材料的粘附情况。结果当将细菌与材料一起放入兔体内,细菌对材料粘附在第3天、第5天最多。对涤纶的粘附较强P<0.01。热解碳在第5天、第7天的细菌粘附明显增强,与聚四氟乙烯相比差异有显著性P<0.05。兔对材料上粘附细菌的清除能力以3天内最快,7天取出材料作细菌培养,仍有细菌生长。静脉注入表皮葡萄球菌产生菌血症或败血症,腹膜腔内生物材料的细菌培养阳性率以第5天、第7天最多,涤纶细菌培养阳性率最高。结论在机体内,同一种细菌对不同的人工心脏瓣膜材料有不同粘附能力,机体对不同材料上粘附细菌的清除能力不同,不易完全清除材料上粘附的细菌。

Study on Bacteria Adhesion to Prosthetic Valve Materials and the Eliminating Activity in Rabbit body

Objective To study the bacteria adhesive pattern on prosthetic valve materials and the eliminating activity in rabbit body for them. Methods The equal amount solution of Staphylococcus epidermidis labeled with 3H-TDR and different materials including low temperature isotropic pyroletic carbon and polytetra fluroethylene(PTFE) were separately implanted into bilateral retroperitoneal space of Japanese long-ear rabbits. Then the pattern of bacteria adhesion to different prosthetic materials in vivo was observed in 1,3,5,7 days after operation. Besides,to implant the different prosthetic materials adhered with bacteria in vitro into retroperitoneal space of rabbit. Then the bacteria elimiting capability of rabbit was studied in different time duration. Moreover the bacteria adhesion to different materials implanted in peritoneal cavity while infusing Staphylococcus intravenously causing sepsis and bacteriemia were observed and compared. Results The peak of bacteria adhesion to materials occurred in the 3rd and 5th day after implanting materials and bacteria together in rabbits body. The adhesion activity of bacteria to Dacron was stronger (P<0.01). The bacteria adhesion to Pyrolytic carbon was obviously increased in the 5th and 7th day. When comparing with that on PTFE,the difference was significant (P<0.05). The eliminating activity of rabbit for the adhered bacteria on material was the strongest on the 3rd day in vitro. After 7 days, the materials were taken out of rabbit body and cultured, showing that there was bacteria growth. In bacteriemia and septicemia caused by infusion of Staphylococcus epidermidis,the bacteria growth was on the peak in 5th and 7th day. The positive rate of bacteria culture in Dacron was the highest.Conclusion The adhesive activities for different prosthetic valve materials are different in vivo. The eliminating activities for the adhesive bacteria to various biomaterials are different in vivo.The adhered bacteria couldn't be eliminated on materials thoroughly in rabbit body.