| Abstrakt: |
The present study was undertaken to experimentally assess a possibility of creating a xenogeneic biological venous-valve prosthetic graft using the vv. saphena medialis of the cattle. The findings obtained in the amino-acid analysis demonstrated that diglycidyl ether ofethylene glycol (DEEG) is an efficient suturing agent for xenoveins. Suturing collagen with DEEG by qualitative and quantitative characteristics appeared superior to treatment with glutaric aldehyde (GA); the content of hydroxylysine was by 30%, and that of lysine by 360% less than in the samples treated with GA. Besides, DEEG reacts with histidine, tyrosine and methionine. The strength characteristics of the DEEG-preserved xenoveins tended to decrease, while elasticity tended to increase, as compared with the GA-treated ones. Treatment with DEEG makes it possible for the material to preserve plasticity, which is of major importance for the appropriate performance of the leaflet apparatus of the xenovein. The amount of the immobilised heparin was determined by means of H34 labelling. It was found that the amount of non-fractionated heparin of "Belmedpreparations", bound to the DEEG-treated surface of xenoveins equalled 6.21 microy/mg. While the amount of immobilized low-molecular-weight heparin "Clexan" was 3.9 microg/mg, with that of non-fractionated heparin "Biochemie" equalling 3.41 microg/mg. For the preserved xenoveins, we used the method of layer-by-layer modification, i.e., "heparin-albumin-heparin". The surface modified by means of low-molecular-weight heparin "Clexan" was noted to have the smoothest relief. This approach appears to show promise in rendering venous-valve prosthetic grafts highly resistant to thrombogenesis. |
