Controlled release of transforming growth factor-beta receptor kinase inhibitor from thermosensitive Chitosan-based hydrogel: application for prevention of capsular contracture / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Capsular contracture has become the most common complication associated with breast implant. Transforming growth factor-beta (TGF-β) is well known for a prominent role in fibrotic diseases. Due to the critical role of TGF-β in pathogenesis of capsular formation, we utilized thermosensitive C/GP hydrogel to controlled release of TGF-β receptor kinase inhibitor (SD208) and investigated their effects on capsular contracture.</p><p><b>METHODS</b>In vitro degradation and drug release of C/GP hydrogel were performed. Twenty-four rabbits underwent subpanniculus implantation with 30 ml smooth silicone implants and were randomly divided into four groups as follows: Group 1 received saline solution; Group 2 received SD208; Group 3 received SD208-C/GP; Group 4 received C/GP. At 8 weeks, the samples of capsular tissues were analyzed by hematoxylin and eosin and immunohistological staining. The mRNA expression of collagen III and TGF-β1 was detected by RT-PCR assay.</p><p><b>RESULTS</b>C/GP hydrogel could be applied as an ideal drug delivery vehicle which supported the controlled release of SD208. SD208-C/GP treatment showed a significant reduction in capsule thickness with fewer vessels. The histological findings confirmed that the lower amounts of inflammatory cells and fibroblasts infiltrate in SD208-C/GP group. In contrast, typical capsules with more vessel predominance were developed in control group. We did not observe the same inhibitory effect of SD208 or C/GP treatment on capsular contracture. Moreover, SD208-C/GP therapy yielded an evident down-regulation of collagen III and TGF-β1 mRNA expression.</p><p><b>CONCLUSIONS</b>This study demonstrated that controlled release of TGF-β receptor kinase inhibitor from thermosensitive C/GP hydrogel could significantly prevent capsule formation after mammary implants.</p>

Microvascular free muscle flap reconstruction of soft-tissue defects with bone exposure after the distal tibial fracture / 中华创伤骨科杂志

Objective To present a method to treat soft tissue defects with bone exposure after the distal tihial fracture.Methods Twenty-six patients who had suffered from the distal tibial fracture complications leading to exposure of the bone or fixation material sought medical help in our department.The internal fixation material was removed and radical revision of dead and infected tissue was carried out in all cases.Five of the 26 cases were treated using a free microvascular muscle flap and the mesh skin graft by one stage.Twenty-one of them were re- paired with the same method by two-stage.Results Follow-ups were 10 to 24 months.The microvascular re- construction was successful in 22 patients.Two of the 26 cases had partial necroses of the skin graft,and the other two cases had delayed wound healing.All the fractures united.Conclusion Microvascular free muscle flap re- construction of the leg is regarded as a reliable method to treat legs with massive soft-tissue defects or defects with bone exposure and chronic infection or fistulation at the distal leg.