T Xi — Page 2 | PubMed Health

PubMed1992

Haemocompatibility of polymer having phospholipid polar groups evaluated by monoclonal antibody method.

The haemocompatibility of a polymer having the phospholipid polar group, poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate(BMA)), was evaluated by a monoclonal antibody SZ-21 (directing specifically against the membrane glycoprotein complex IIIa of human platelet) radioimmunoassay method. The study showed that poly(MPC-co-BMA) possessed better haemocompatibility than segmented polyurethane (SPEU). Radioactivity of platelets adhered (counts per min/cm) on a polyethylene (PE) tube coated with poly(MPC-co-BMA) was 19.51 +/- 5.58, with albumin; 20.05 +/- 7.29, with SPEU having sulphonated group; 76.10 +/- 18.9, with SPEU; 287.0 +/- 95.0, PE treated by plasma irradiation; 2091 +/- 261, and original PE was 1772 +/- 116. The results were further certified by scanning electron microscopic observations.

Antibodies, Monoclonal↗

PubMed1992

Effect of pretreatment with epoxy compounds on the mechanical properties of bovine pericardial bioprosthetic materials.

Early failures of bovine pericardial heart valves are due to leaflet perforation, tearing and calcification. Since glutaraldehyde fixation has been shown to produce marked changes in leaflet mechanics and has been linked to development of calcification, bovine pericardium fixed with the four hydrophilic epoxy formulations and their mechanical properties are studied in this paper. We measured the thicknesses, shrinkage temperatures, stress relaxations and stress-strain curves of bovine pericardiums after different treatments with (1) non-treatment (fresh), (2) glutaraldehyde (GA), (3) epoxy compounds followed by the posttreatment with GA (EP 1#, EP 2#), and (4) epoxy compounds (EP 3# and EP 4#). Results of this study showed that the hydrophilic epoxy compounds are good crosslinking agents. There are no significant differences of shrinkage temperature and ultimate tensile stress among all tissue samples pretreated with GA, EP 1# and EP 2#. However, the stress relaxations of tissue-samples pretreated with epoxy compounds followed by the posttreatment with GA (EP 1# and EP 2#) are significantly slower than that pretreated with GA, and the strains at fracture of EP 1# and EP 2# are also significantly larger than that of GA or epoxy compounds. These facts show that the bovine pericardium pretreated with the epoxy compound followed by the posttreatment with GA (EP 1# and EP 2#) possesses greater tenacity and potential durability in dynamic stress.

Animals↗