Objective To develop a deantigenated porcine bone graft through enzyme treatment and to study the biomechanical properties and osteoinductivity of the xenogeneic bone graft. Methods Deantigenated xenogeneic bone was prepared from porcine bone by a series treatment including α-galactosidase (α-Gal) treatment, freezedrying and irradiation at a does of 25 kGy. Samples were divided into 4 groups according to the treatment methods: fresh bone (group A); deantigenated bone (group B); deantigenated and freezedried bone (group C); deantigenated-freezedried-irradiated bone(group D). SEM observation to group B samples was performed and the diameters of the caves of the porcine cancellous bone were measured. The α-Gal contents of samples of groups A, B, D were measured by ELISA. The effects of different treatments on porcine bone mechanic properties were evaluated through compressive test of 4 groups. The prepared porcine cortical bone were demineral ized and ectopically implanted into muscle groups of hind l imbs of Wistar rats as experimental group, and the demineral ized cortical bone which were inacitviated by high temperature and pressure were implanted as control group. Histological observation was performed and ALP activity was tested at different time postoperatively to investigate the osteoinductivity of the xenogeneic bone implants. Results The porous structure of prepared porcine cancellous bone was similar to that of human cancellous bone. The diameters of the caves were between 150-600 μm. The A value of the groups A, B, D was 0.358 ± 0.027, 0.191 ± 0.011, 0.191 ± 0.009, respectively, with statistically differences between groups (P lt; 0.05). While the biomechanical properties among 4 groups had no statistically difference (P gt; 0.05). Histological observation showed mesenchymal cells immigrated into cartilage and converted into chondrocytes at 3 weeks postoperatively. Cartil iage was formed at 4 weeks and osteoid and more adult cartilage was formed at 6 weeks within the implants of experimental group, while there was no bone formation in control group. ALP activity of experimental group at different times were obviously higher than that of the control group (P lt; 0.05). Conclusion The main xenogeneic antigen of the porcine bone was removed while the mechanic properties and osteoinductivity remained, thus it may be a suitable bone substitute for cl inical use.
ObjectiveTo evaluate the operative technique and clinical efficacy of laparoscopic splenectomy (LS) combined with esophagogastric devascularization in treatment of portal hypertension induced by liver cirrhosis. MethodsTwelve cases with esophageal and gastric varices induced by portal hypertension and liver cirrhosis were treated by the LS combined with esophagogastric devascularization in our department from March 2009 to August 2010, which clinical data were analyzed and summarized retrospectively. ResultsThe splenic artery was ligated before the treatment of splenic pedicle in 12 cases, LS combined with pericardial devascularization was successfully performed in 10 cases, 7 cases of which were treated by the level two transection method of splenic pedicle, and 2 cases were converted to open surgery due to intraoperative bleeding. In 10 cases, the operative time was 180-300 min (average 210 min), and intraoperative blood loss was 200-1 000 ml (average 480 ml). The postoperative hospital stay was 8-15 d (average 9 d)， the postoperative complications included plural effusion （lt;300 ml） in 2 cases， mild ascites （lt;300 ml） in 2 cases, and mild pancreatic leakage in 1 case， but all were cured eventually， and no mortality occurred. Followup was conducted in 12 patients for 4 to 20 months (average 7 months), and no rebleeding occurred. ConclusionsLS combined with pericardial devascularization is relatively safe and effective methods in treatment of portal hypertension induced by liver cirrhosis. The keys to success include ligation of splenic artery, and the use of harmonic scalpel combined with ligasure to treat splenic pedicle.