Biomechanical Evaluation of an Atraumatic Polymer-assisted Peripheral Nerve Repair System Compared with Conventional Neurorrhaphy Techniques.

Background: Microsuturing, the gold standard for peripheral nerve repair, can create tension and damage at the repair site, potentially impacting regeneration and causing neuroma formation. A sutureless and atraumatic polymer-assisted system was developed to address this challenge and support peripheral nerve repair. The system is based on a biocompatible and biodegradable biosynthetic polymer and consists of a coaptation chamber and a light-activated polymer for securing to the nerve.

Ageing affects chondroitin sulfates and their synthetic enzymes in the intervertebral disc.

The depletion of chondroitin sulfates (CSs) within the intervertebral disc (IVD) during degenerative disc disease (DDD) results in a decrease in tissue hydration, a loss of fluid movement, cell apoptosis, a loss of nerve growth inhibition and ultimately, the loss of disc function. To date, little is known with regards to the structure and content of chondroitin sulfates (CSs) during IVD ageing. The behavior of glycosaminoglycans (GAGs), specifically CSs, as well as xylosyltransferase I (XT-I) and glucuronyltransferase I (GT-I), two key enzymes involved in CS synthesis as a primer of glycosaminoglycan (GAG) chain elongation and GAG synthesis in the nucleus pulposus (NP), respectively, were evaluated in a bovine ageing IVD model.

Cross-linking of a biopolymer-peptide co-assembling system.

Unlabelled: The ability to guide molecular self-assembly at the nanoscale into complex macroscopic structures could enable the development of functional synthetic materials that exhibit properties of natural tissues such as hierarchy, adaptability, and self-healing. However, the stability and structural integrity of these kinds of materials remains a challenge for many practical applications. We have recently developed a dynamic biopolymer-peptide co-assembly system with the capacity to grow and undergo morphogenesis into complex shapes.

An injectable, in situ forming type II collagen/hyaluronic acid hydrogel vehicle for chondrocyte delivery in cartilage tissue engineering.

In this study, chondrocytes were encapsulated into an injectable, in situ forming type II collagen/hyaluronic acid (HA) hydrogel cross-linked with poly(ethylene glycol) ether tetrasuccinimidyl glutarate (4SPEG) and supplemented with the transforming growth factor β1 (TGFβ1). The chondrocyte-hydrogel constructs were cultured in vitro for 7 days and studied for cell viability and proliferation, morphology, glycosaminoglycan production, and gene expression. Type II collagen/HA/4SPEG formed a strong and stable hydrogel, and the chondrocytes remained viable during the encapsulation process and for the 7-day culture period.

Encapsulated cells for long-term secretion of soluble VEGF receptor 1: Material optimization and simulation of ocular drug response.

Anti-angiogenic therapies with vascular endothelial growth factor (VEGF) inhibiting factors are effective treatment options for neovascular diseases of the retina, but these proteins can only be delivered as intravitreal (IVT) injections. To sustain a therapeutic drug level in the retina, VEGF inhibitors have to be delivered frequently, every 4-8weeks, causing inconvenience for the patients and expenses for the healthcare system. The aim of this study was to investigate cell encapsulation as a delivery system for prolonged anti-angiogenic treatment of retinal neovascularization.

An ex-vivo multiple sclerosis model of inflammatory demyelination using hyperbranched polymer.

Multiple sclerosis (MS) is characterized by the presence of inflammatory demyelinating foci throughout the brain and spinal cord, accompanied by axonal and neuronal damage. Although inflammatory processes are thought to underlie the pathological changes, the individual mediators of this damage are unclear. In order to study the role of pro-inflammatory cytokines in demyelination in the central nervous system, we have utilized a hyperbranched poly(2-dimethyl-aminoethylmethacrylate) based non-viral gene transfection system to establish an inflammatory demyelinating model of MS in an ex-vivo environment.

An injectable vehicle for nucleus pulposus cell-based therapy.

An injectable hydrogel, acting as a reservoir for cell delivery and mimicking the native environment, offers promise for nucleus pulposus (NP) repair and regeneration. Herein, the potential of a stabilised type II collagen hydrogel using poly(ethylene glycol) ether tetrasuccinimidyl glutarate (4S-StarPEG) cross-linker, enriched with hyaluronic acid (HA) was investigated. The optimally stabilised type II collagen hydrogel was determined by assessing free amine groups, resistance to enzymatic degradation, gel point.