Grant-in-Aid for Developmental Scientific Research (B).
Biomedical engineering/Biological material science
|Research Institution||The Jikei University School of Medixine|
FURUHATA Hiroshi The Jikei Univ.Schl.of Med., Med.Dept.Assoc.Prof., 医学部, 助教授 (70056985)
相田 聡 東芝研究開発センター, 情報通信システム研究所, 主務
IIJIMA Shiro Kyoritsu Coll.of Phrm., Phrm.Dept.Assistant, 薬学部, 助手 (30222798)
KIMURA Miyako Kyoritsu Coll.of Phrm., Phrm.Dept.Assoc.Prof., 薬学部, 助教授 (20050734)
浜野 研司 東京慈恵会医科大学, 第4内科学, 助手 (20231524)
HARA Masatada The Jikei Univ.Schl.of Med., Med.Dept.Lecturer, 医学部, 講師 (60147345)
鈴木 義則 株式会社東芝, 研究開発センター, 主任研究員
鈴木 義規 株式会社東芝, 研究開発センター, 主任研究員
SUZUKI Yoshinori Toshiba Research & Development Center, Chief Research
|Project Fiscal Year
1994 – 1995
Completed(Fiscal Year 1995)
|Budget Amount *help
¥11,600,000 (Direct Cost : ¥11,600,000)
Fiscal Year 1995 : ¥2,700,000 (Direct Cost : ¥2,700,000)
Fiscal Year 1994 : ¥8,900,000 (Direct Cost : ¥8,900,000)
|Keywords||ultrasound / thrombolysis / plasminogen activator / thrombus / FDP / recanalization / coronary artery / ischemic disease / 超音波 / 血栓溶解 / plasmlnogen activator / 血栓 / 血流再開通 / 冠動脈 / 虚血障害 / 血栓溶解療法 / 超音波照射 / 標的療法 / 塞栓 / 超音波併用血栓溶解療法|
Foundamental and experimental studies of a new thrombolytic method with ultrasound have been performed for the practical use. This method features the early recanalization and the targeting to the embolus.
Thrombolytic drug used for this study was a tissue typed plasminogen activator (rt-PA) 2mug/ml in in-vitro experiment and 1mg/kg venous injection in animal experiment. The ultrasound was contineous wave at 100KHz-1.2MHz in frequency and 0-0.75W/cm^2 in power, and 30 min. irradiation. We obtained the following results.
(1) Ultrasonic frequency characteristics : It was verified from an in vitro experiment that the thrombolytic effect was particularly enhanced be the ultrasonic irradiation which frequency was ranged from 100KHz to 300KHz. This result was derived from the evaluation of the decreasing ratio of clot weight and the quantity of FDP-DD in the sloution.
(2) Ultrasonic power tendency : The enhancement of thrombolysis was linearly related to the increase of ultrasonic irradiation p
(3) Mechanism of the enhancement of thrombolysis : The residual solution of thrombolysis was examined by the electro fluence. The spectrum pattern of the solution was the same between the combined new method and the administration of rt-PA alone. The spectral concentration was higher in a new combined method.
(4) High-speed recanalization in animal experiment : The embolus was formed in the left anterior decednding coronary artery as a model for the acute myocardiac infarction. In comparison with a new combined method and rt-PA alone, the recanalization time by a new method was 15 min as the mean, which was one third of the recanalization time by rt-PA alone.
(5) Evaluation of safety hazard : As the result of the pathological evaluation of the skin, the chest wall and the myocardium, there was no damage in those tissues for the ultrasonic power level at 0.75 W/cm^2.
(6) Aspect to the clinical use : This new combined thrombolytic method have a quite high possibililty of the clinical application, as the first choice of the thrapeutic technique for the ischemic desease with emboli.
It was concluded that this new thrombolytic method had high possibility for the early recanalization of the ischemic desease with emboli. Less