title: Titania gel reduces thrombin generation.
abstract: Titanium alloy (Ti) commonly is used for long-term blood pumps as a conventional blood contacting material. Thrombus formation in the pump, however, is still a critical problem. Once thrombin is generated on the Ti surface, it activates platelets and the coagulation cascade, leading to thrombus formation. It would be expected that an inhibition of thrombin generation on a blood-contacting surface would prevent thrombus formation. In this study, the titania gel (Ti-gel) on the surface of Ti was formed with chemical modification. The surface structure and its effects on the coagulation cascade were evaluated. Scanning electron microscopic study revealed numerous cracks on the dried surface of Ti-gel, indicating a water-enriched layer. Blood coagulation on the Ti-gel was less than that on the Ti. Generated thrombin on the Ti-gel was less than that on the Ti in both the extrinsic and intrinsic pathways. There was no statistical difference of thrombin degradation. These results suggest that coagulation cascade on the Ti surface was inhibited by the Ti-gel formation. The Ti-gel may have better antithrombogenic characteristics for blood pumps because of its antiblood-coagulation effects.
authors.affiliation: Michael E DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas 77030, USA. ishitoya@wd6.so-net.ne.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishitoya
authors.forename: Masaki
authors.initials: M
authors.lastname: Kawamura
authors.forename: Joerg
authors.initials: J
authors.lastname: Linneweber
authors.forename: Tadashi
authors.initials: T
authors.lastname: Motomura
authors.forename: Seiji
authors.initials: S
authors.lastname: Ichikawa
authors.forename: Ikuya
authors.initials: I
authors.lastname: Nishimura
authors.forename: Julia
authors.initials: J
authors.lastname: Glueck
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Shinohara
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Nosé
mesh_terms: D001672:Biocompatible Materials / Q000627:therapeutic use*; D001777:Blood Coagulation / Q000187:drug effects / Q000502:physiology; D002318:Cardiovascular Diseases / Q000503:physiopathology / Q000628:therapy*; D005782:Gels; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006490:Hemostatics / Q000032:analysis*; D006801:Humans; D066298:In Vitro Techniques; D013917:Thrombin / Q000032:analysis*; D013927:Thrombosis / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control*; D013997:Time Factors; D014025:Titanium / Q000627:therapeutic use*
chemical_list: D001672:Biocompatible Materials; D005782:Gels; D006490:Hemostatics; C009495:titanium dioxide; D014025:Titanium; D013917:Thrombin