Peihua Zhang

Optic nerve regeneration in polyglycolic acid-chitosan conduits coated with recombinant L1-Fc.

Autografts have been extensively studied to facilitate optic nerve (ON) regeneration in animal experiments, but the clinical application of this approach to aid autoregeneration has not yet been attempted. This study aims to explore the guided regeneration by an artificial polyglycolic acid–chitosan conduit coated with recombinant L1-Fc. Consistent with previous studies; in vitro assay showed that both chitosan, a natural biomaterial, and the neural cell adhesion molecule L1-Fc enhanced neurite outgrowth. Rat optic nerve transection was used as an in vivo model. The implanted PGA-chitosan conduit was progressively degraded and absorbed, accompanied by significant axonal regeneration as revealed by immunohistochemistry, anterograde and retrograde tracing. The polyglycolic acid–chitosan conduit coated with L1-Fc showed more effective to promote axonal regeneration and remyelination. Taken together, our observations demonstrated that the L1-Fc coated PGA–chitosan conduits provided a compatible and supportive canal to guild the injured nerve regeneration and remyelination.

Radial Compressive Properties of the Biodegradable Braided Regeneration Tubes for Peripheral Nerve Repair

Different regeneration tubes braided from biodegradable material poly (glycolide-co-L-lactide) (PGLA) for peripheral nerve repair and their radial compressive properties are presented. The influences of the braided structure and braiding angle are discussed. The results have shown that the nerve tube braided with the triaxial structure and the braiding angle at 60 has a higher ability to resist the radial compressions.

In Vitro Degradation Behaviours of PDO Monofilament and Its Intravascular Stents with Braided Structure

Abstract Biodegradable intravascular stent has attracted more and more focus in recent years as an effective solution for angiostenosis. Ideal stents were expected to exhibit sufficient radial force to support the vascular wall, while suitable flexibility for the angioplasty. After vascular remodeling, stents should be degraded into small molecular and be eliminated from human body, causing no potential risk. In this paper, poly-p-dioxanone (PDO) monofilament was braided into net structure with four different braiding density, two of which exhibited sufficient radial force larger than 30 kPa, and three of which showed the bending rigidity within 11.7–88.1 N•mm2. The degradation behaviors of monofilaments and stents have been observed for 16 weeks. The findings obtained indicate that degradation first occurred in morphology region, which induced temporary increase of crystallinity, monofilament bending rigidity and stent mechanical properties. During this period, monofilament tends to be hard and brittle and lost its tensile properties. Then the crystalline region was degraded and stent mechanical properties decreased. All the results reveal that the PDO intravascular stents with braided structure were able to afford at least 10 weeks of sufficient support to the vascular wall.