Electrospun hydroxyapatite loaded L-polylactic acid aligned nanofibrous membrane patch for rotator cuff repair.

Rotator cuff repair remains a challenge clinically due to the high retear rate after surgical intervention. There is a significant need to develop functional biomaterials facilitating tendon-to-bone integration. In this study, hydroxyapatite (HA) incorporated polylactic acid (PLLA) aligned nanofibrous membranes were fabricated by electrospinning as a low-cost sustainable rotator cuff patch. The morphology, physical, mechanical and in vitro cell assays of the nanofibrous membranes were characterized. The results showed that the nanofibrous membrane maintained a rough surface and weakened hydrophobicity. It has excellent cytocompatibility, and the cells were oriented along the direction of fiber arrangement. What's more, the PLLA-HA nanofibrous membrane could increase the alkaline phosphatase (ALP) expression in rat bone marrow mesenchymal stem cells (BMSCs), indicating that the electrospinning PLLA-HA nanofibrous membrane can better induce the bone formation of rat BMSCs cells. When the mass ratio of PLLA to HA exceeds 3: 1, with the increase of the HA content, the patch showed rising induction ability. The results suggested that electrospinning PLLA-HA nanofibrous membranes are an ideal patch for promoting tendon-bone healing and reducing the secondary tear rate. Furthermore, the use of biodegradable polymers and low-cost preparation methods presented the possibility for commercial production of these nanofibrous membranes.

Efficacy and safety of biodegradable polymer biolimus-eluting stents versus durable polymer drug-eluting stents: a meta-analysis.

BACKGROUNDS: Drug-eluting stents (DES) with biodegradable polymers have been developed to address the risk of thrombosis associated with first-generation DES. We aimed to determine the efficacy and safety of biodegradable polymer biolimus-eluting stents (BES) versus durable polymer DES. METHODS: Systematic database searches of MEDLINE (1950 to June 2013), EMBASE (1966 to June 2013), the Cochrane Central Register of Controlled Trials (Issue 6 of 12, June 2013), and a review of related literature were conducted. All randomized controlled trials comparing biodegradable polymer BES versus durable polymer DES were included. RESULTS: Eight randomized controlled trials investigating 11,015 patients undergoing percutaneous coronary interventions were included in the meta-analysis. The risk of major adverse cardiac events did not differ significantly between the patients treated with the biodegradable polymer BES and the durable polymer DES (Relative risk [RR], 0.970; 95% CI, 0.848-1.111; p = 0.662). However, biodegradable polymer BES was associated with reduced risk of very late ST compared with the durable polymer DES, while the risk of early or late ST was similar (RR for early or late ST, 1.167; 95% CI 0.755-1.802; p = 0.487; RR 0.273; 95% CI 0.115-0.652; p = 0.003; p for interaction = 0.003). CONCLUSIONS: In this meta-analysis of randomized controlled trials, treatments with biodegradable polymer BES did not significantly reduce the risk of major adverse cardiac events, but demonstrated a significantly lower risk of very late ST when compared to durable polymer DES. This conclusion requires confirmation by further studies with long-term follow-up. PROSPERO REGISTER NUMBER: http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013004364#.UnM2lfmsj6J.