Biomedical subjects

E G Parent

Publications and source records attributed to E G Parent.

2 recordsLinked to original sources

PubMed1992

Effect of hylan on cartilage and chondrocyte cultures.

The protective role of hylan, a hyaluronan [hyaluronic acid (HA)] derivative, was studied in explanted bovine cartilage and isolated chondrocytes. Cartilage and chondrocytes were exposed to degradative enzymes (lysate from activated polymorphonuclear leukocytes), oxygen-derived free radicals (ODFR), conditioned media from mononuclear cells (MCCM), and interleukin-1 (IL-1), in the presence and absence of hylan. The effect of HA was also studied. In cartilage explants susceptibility to pertubation was evaluated in terms of 35S release and proteoglycan depletion and was compared to control cultures; high viscosity hylan was found to reduce 35S release in cartilage explants caused by degradative enzymes, ODFR, MCCM, and IL-1. The hylan effect was reversible and viscosity-dependent. In chondrocyte cultures, high viscosity hylan was effective in reducing cell injury caused by degradative enzymes and ODFR. The data suggest that the glycosaminoglycan hylan, as well as native HA, may mediate exposure to and/or response to stimuli associated with initiation of degenerative processes in cartilage tissues.

Animals↗

PubMed1991

Hylan gel composition for percutaneous embolization.

Viscoelastic, pseudoplastic, radiopaque injectable hylan gel for percutaneous embolization was developed and evaluated by in vitro and in vivo tests. The embolization gel is composed of cross-linked hylan (hyaluronan, hyaluronate), tantalum, microcrystalline cellulose, hexamethonium chloride, and thrombin. Upon delivery through small-lumen catheters to the appropriate vascular site, the gel induces formation of a solid blood/gel coagulum. Results from animal studies (rat aorta, rabbit auricular artery) demonstrate that formation of complete and long-lasting arterial blockage is readily achievable without complications due to blood flow, partial vessel obstruction, uncontrolled polymerization, or movement of the gel or its components (specifically thrombin and hexamethonium chloride) into the circulation. Microscopic evaluation indicates that arterial occlusion initially occurs as a result of the injected gel and formed fibrin; at 7 weeks and beyond, arteries are occluded by injected gel, inflammatory cells and fibrosis (scar tissue).

Animals↗