Objective： In our previous work, we prepared a type of chitosan hydrogel with excellent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was...Objective： In our previous work, we prepared a type of chitosan hydrogel with excellent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was used to repair the articular cartilage defects. Methods： Chitosan hydrogels were prepared with a crosslinker formed by combining 1,6-diisocyanatohexane and polyethylene glycol. Chitosan hydrogel scaffold was seeded with rabbit chondrocytes that had been cultured for one week in vitro to form the preliminary tissue-engineered cartilage. This preliminary tissue-engineered cartilage was then transplanted into the defective rabbit articular cartilage. There were three treatment groups： the experimental group received preliminary tissue-engineered cartilage; the blank group received pure chitosan hydrogels; and, the control group had received no implantation. The knee joints were harvested at predetermined time. The repaired cartilage was analyzed through gross morphology, histologically and immunohistochemically. The repairs were scored according to the international cartilage repair society （ICRS） standard. Results： The gross morphology results suggested that the defects were repaired completely in the experimental group after twelve weeks. The regenerated tissue connected closely with subchondral bone and the boundary with normal tissue was fuzzy. The cartilage lacuna in the regenerated tissue was similar to normal cartilage lacuna. The results of ICRS gross and histological grading showed that there were significant differences among the three groups （P〈0.05）. Conclusions： Chondrocytes implanted in the scaffold can adhere, proliferate, and secrete extracellular matrix. The novel tissue-engineered cartilage constructed in our research can completely repair the structure of damaged articular cartilage.展开更多
Objective: To sum up experiences and lessons about management of soft-tissue reconstruction in open tibial fracture over a 6-year period. Methods: Twenty-two flap reconstructions were performed to treat soft-tissue de...Objective: To sum up experiences and lessons about management of soft-tissue reconstruction in open tibial fracture over a 6-year period. Methods: Twenty-two flap reconstructions were performed to treat soft-tissue defect of 22 patients with open tibial fracture Type IIIB (Gustilo) from 1993 to 1998. The cases were analyzed and discussed retrospectively after follow up of 12-61 months. Results: The size of the flap ranged from 6.6 cm 2 to 28.18 cm 2 and the rate of flap failure was 13.6%. Besides, 3 partial necrosis and 2 postoperative infections occurred in this series. Conclusions: For soft tissue defect of delayed open tibial fracture Type IIIB, flap reconstruction is still an optimal option. The experiences we obtained are ① to design a triangular skin extension or a small Z-plasty over the pedicle to reduce the flap tension; ② to select a unilateral external fixation to provide convenience for any secondary manipulation; and ③ to use serial debridement to diminish flap failure.展开更多
基金supported by the National Natural Science Foundation of China(Nos.81171472,81201407,and 81071270)the Innovation Team Project of Sichuan Provincial Education Department(No.13TD0030)+1 种基金the Major Transformation Cultivation Project of Sichuan Provincial Education Department(No.15CZ0021)the Science and Technology Project of Nanchong City(No.14A0021),China
文摘Objective： In our previous work, we prepared a type of chitosan hydrogel with excellent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was used to repair the articular cartilage defects. Methods： Chitosan hydrogels were prepared with a crosslinker formed by combining 1,6-diisocyanatohexane and polyethylene glycol. Chitosan hydrogel scaffold was seeded with rabbit chondrocytes that had been cultured for one week in vitro to form the preliminary tissue-engineered cartilage. This preliminary tissue-engineered cartilage was then transplanted into the defective rabbit articular cartilage. There were three treatment groups： the experimental group received preliminary tissue-engineered cartilage; the blank group received pure chitosan hydrogels; and, the control group had received no implantation. The knee joints were harvested at predetermined time. The repaired cartilage was analyzed through gross morphology, histologically and immunohistochemically. The repairs were scored according to the international cartilage repair society （ICRS） standard. Results： The gross morphology results suggested that the defects were repaired completely in the experimental group after twelve weeks. The regenerated tissue connected closely with subchondral bone and the boundary with normal tissue was fuzzy. The cartilage lacuna in the regenerated tissue was similar to normal cartilage lacuna. The results of ICRS gross and histological grading showed that there were significant differences among the three groups （P〈0.05）. Conclusions： Chondrocytes implanted in the scaffold can adhere, proliferate, and secrete extracellular matrix. The novel tissue-engineered cartilage constructed in our research can completely repair the structure of damaged articular cartilage.
文摘Objective: To sum up experiences and lessons about management of soft-tissue reconstruction in open tibial fracture over a 6-year period. Methods: Twenty-two flap reconstructions were performed to treat soft-tissue defect of 22 patients with open tibial fracture Type IIIB (Gustilo) from 1993 to 1998. The cases were analyzed and discussed retrospectively after follow up of 12-61 months. Results: The size of the flap ranged from 6.6 cm 2 to 28.18 cm 2 and the rate of flap failure was 13.6%. Besides, 3 partial necrosis and 2 postoperative infections occurred in this series. Conclusions: For soft tissue defect of delayed open tibial fracture Type IIIB, flap reconstruction is still an optimal option. The experiences we obtained are ① to design a triangular skin extension or a small Z-plasty over the pedicle to reduce the flap tension; ② to select a unilateral external fixation to provide convenience for any secondary manipulation; and ③ to use serial debridement to diminish flap failure.
