Repair of extrahepatic bile duct defect using a collagen patch in a Swine model.

Extrahepatic bile duct (EBD) injury can happen during surgery. To repair a defect of the EBD and prevent postoperative biliary complications, a collagen membrane was designed. The collagen material was porous, biocompatible, and degradable and could maintain its shape in bile soaking for about 4 weeks. The goal was to induce rapid bile duct tissue regeneration. Twenty Chinese experimental hybrid pigs were used in this study and divided into a patch group and a control group. A spindle-shaped defect (20 mm × 6 mm) was made in the anterior wall of the lower EBD in the swine model, and then the defect was reconstructed using a collagen patch with a drainage tube and wrapped with greater omentum. Ultrasound was performed at 2, 4, 8, and 12 weeks postoperatively. Liver function tests and white blood cell count (WBC) were measured. Hematoxylin-eosin staining, cytokeratin 7 immunohistochemical staining, and Van Gieson's staining of EBD were used. The diameter and thickness of the EBD at the graft site were measured. There was no significant difference in liver function tests or WBC in the patch group compared with the control group. No evidence of leakage or stricture was observed, but some pigs developed biliary sludge or stone at 4 and 8 weeks. The drainage tube was lost within 12 weeks. The neo-EBD could withstand normal biliary pressure 2 weeks after surgery. Histological study showed the accessory glands and epithelial cells gradually regenerated at graft sites from 4 weeks, with increasing vessel infiltration and decreasing inflammation. The collagen fibers became regular with full coverage of epithelial cells. The statistical analysis of diameter and thickness showed no stricture formation at the graft site, but the EBD wall was slightly thicker than in the normal bile duct due to collagen fiber deposition. The structure of the neo-EBD was similar to that of the normal EBD. The collagen membrane patch associated with a drainage tube and wrapped with greater omentum effectively induced the regeneration of the EBD defect within 12 weeks.

[Factors influencing the progression-free survival time of prostate cancer patients after endocrine therapy].

OBJECTIVE: The progression of prostate cancer (PCa) after endocrine therapy varies widely in different PCa patients. This study aims to analyze the factors that influence the progression-free survival time of PCa patients after endocrine therapy in an attempt to improve the prognosis of the disease. METHODS: We reviewed the clinicopathological data of 116 cases of prostate cancer treated by endocrine therapy, analyzed the clinicopathological factors that influence the progression-free survival time of PCa patients using univariate (log-rank test) and multivariate Cox proportional hazard models, and investigated the correlation among these factors by Spearman rank correlation analysis. RESULTS: In the stepwise Cox proportional hazard model, the independent prognostic factors for PCa progression after endocrine therapy were found to be Gleason score (P < 0.01) and clinical stages (P < 0.01). The hazard of PCa progression after endocrine therapy increased 2.126 times that of the baseline for each unit of increase in Gleason score, and 6.625 times for each unit of increase in the clinical stage. The pretreatment PSA level was correlated with both clinical stages (P < 0.01) and Gleason score (P < 0.01). CONCLUSION: Clinical stages and Gleason score were important factors that influenced the progression-free survival time after endocrine therapy in this cohort of PCa patients.

Extrahepatic bile duct regeneration in pigs using collagen scaffolds loaded with human collagen-binding bFGF.

Extrahepatic bile duct defects and their complications are benign lesions but with malignant outcomes. Extrahepatic bile duct regeneration at the injury site could be important for the repair. In our previous work, a human basic fibroblast growth factor (bFGF) fused with a collagen-binding domain (CBD) was produced to activate the collagen membrane to obtain targeted tissue regeneration. This collagen/growth factor functional biomaterial could promote the regeneration of skin, bladder and full-thickness abdominal wall by accelerating vascularization and cellularization of autologous tissues. We speculate that the functional biomaterial could also provide the repairing effect on extrahepatic bile duct injuries. Using a pig extrahepatic bile duct injury model, we found that the collagen/CBD-bFGF composite biomaterial could significantly promote the extrahepatic bile duct regeneration at the injury site without causing structure deformation or hepatic dysfunction during both short- and long-time observations.