Objective To develop a new tissue engineering bone material which has an antiinfective function. Methods Collagen loaded bio-derived bone material was made by using type I collagen and allograft bone. WO-1was absorbed to collagen loaded bio-derived bone, then the morphological feature of the new bone material was observed by scanning electronic microscopy.3 H tetracycline was diluted by WO-1 solution, and was absorbed to collagen loaded bio-derived bone，then the releasing kinetics of WO-1 was detected by 3 Htetracycline in vitro. WO-1 bioderived bone material was grafted into a culturemedium with staphylococcus aureus, escherichia coli, and pseudomonas aeruginosato observe its bacteriostasis ability. WO-1 bio-derived bone material was grafted into radius of defected rabbits, the concentration of WO-1 was detected onthe 9th, 16th, 23th, and 30th day byHLPC in blood, in bone and in muscle. The bacteriostasis ability of WO-1 loaded bio-derived bone was tested in vitro and in vivo. Results WO-1 loaded bioderived bone maintained natural network pore system and the surface of network pore system was coated with collagen membrane. The release of WO-1 from WO-1 loaded bioderived bone showed bursting release on the 1st day, then showed stable release. WO-1 loaded bioderived bone showed lasting and stable bacteriostasis to common pathogens of orthopaedic infections. The high concentration of WO-1 was observed in bone tissue and in muscle tissue at differenttime points and the difference among groups had no significance（P＞0.05）, while the concentration of WO-1 in blood was very low（P＜0.05). Conclusion WO-1 loaded bioderived bone has good capability of drug controlled-release and bacteriostasis.
Objective To investigate the effect of anti-infective reconstitutedbone xenograft (ARBX) as primary grafting on repair of a segmental contaminateddefect in canine radius. Methods The contaminated segmentaldefects of 1.5 cm were made in both radius of 8 canine and 1 ml of staphylococal suspension was injected into the defect region at a concentration of 5×106 CFU/ml. ARBX(experimental side) or RBX(control side) was implanted into the two sides of the defects respectively as primary grafting followed by internal fixation. The results were compared between the two grafting materials in repairing the contaminated segmental defect. Results In ARBX side, the defects were repaired completely in 5 cases and partially in 1 case, and there existed no osteomyelitis in all cases; while in RBX side, the defects were repaired partially in 1 case and were not repaired in 5 cases after 6 months of operation, and there existed osteomyelitis in all cases. Conclusion Besides its b osteoinductive and osteoconductive activity, ARBX is highly antibacterial and can be used as primary grafting in repairing contaminated segmental defects.
Abstract In order to study the influence of chitosan on bone infection, 27 New-Zealand rabbits were randomly divided into 3 groups. According to the Norden technique, the model of osteomyelitis of the tuberosity of tibia was produced experimentally by injection of staphylococcus aureus.Immediately following injection of the staphylococci, the chitosan gel, acetic acid solution and sterile distilled water were injected into the bones in the 3 groups respectively. The latter two groups were served as control. The severity of the infection was evaluated by clinical symptoms and signs, radiographicdata as well as the bone culture and bacterial counts. Compared the results from chitosan with the other two controls, it was found that the local injection ofchitosan could not reduce the incidence of bone infection, however, it could provide actual improvement when other data were concerned. The effects of chitosangel might be attributed to its bacteriostatic and immunological activity as well as its slow degradation in the body.