1995 Fiscal Year Final Research Report Summary
Reasearch on pathogenesis and prevention of small caliber prosthetic occlusions
Project/Area Number |
05404043
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Research Category |
Grant-in-Aid for General Scientific Research (A)
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Allocation Type | Single-year Grants |
Research Field |
General surgery
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Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
MISHIMA Yoshio Tokyo Med.& Dent.Univ, Fac.of Med, Professor, 医学部, 教授 (00010158)
|
Co-Investigator(Kenkyū-buntansha) |
KITAGO Kuninaki Tokyo Med.& Dent.Univ, Fac.of Med, Assistant, 医学部, 助手 (00161472)
ITO Masashi Tokyo Med.& Dent.Univ, Fac.of Med, Assistant, 医学部, 助手 (30223184)
NIHEI Zenro Tokyo Med.& Dent.Univ, Fac.of Med, Lecturer, 医学部, 講師 (00189341)
|
Project Period (FY) |
1993 – 1995
|
Keywords | prosthetic graft / arterial reconstruction / pseudointimal hyperplasia / early occlusion / late occlusion / patent rate / antithrombogenisity / vascular surgery |
Research Abstract |
The aim of this research is to develop new small-caliber prosthesis with long patency, enabling clinical application, and elucidate etiology of graft failures, including neointimal hyperplasia, and its prevention. Dacron grafts, 2mm in diameter and 2cm in length, coated with mixing solution of excellent anti-thrombogenic substance, 2-methacryl-oxyethyl phosphoryl-choline (MPC) polymer and segmented polyurethane (SPU), were implanted in the cervical artery of rats. In the control group, the internal lumen of the graft was covered with red thrombi 90 minutes after implantation and all grafts were occluded within 3 days. On the other hand, MPC grafts had no adhesion of thrombus 5 days after implantation, and its inner surface was covered with thin fibrin-like membrane one week after implantation. After 2 months, smooth neointima was observed, and its early patency was excellent. These results indicate the MPC grafts have possibilities of a clinical application with long patency after adding more sufficient anchoring of neointima against the grafts. Neointimal hyperplasia was significantly suppressed by administration of anti-PDGF drug and its development was significantly differed among various kinds of ePTFE grafts. These results showed pharmacological intervention and reforming structures of grafts may improve long-term patency. Clinically, immunohistochemical studies of occluded graft's anastomosis demonstrated that neointimal denudution is a new factor contributing to late graft failure in addition to neointimal hyperplasia.
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Research Products
(6 results)