組織型プラズミノゲン活性化剤誘発性血栓解離に対する超音波の効果
1Department of Hematology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
Circulation
|October 1, 1992
まとめ
組織型プラズミノゲン活性化剤 (t-PA) と組み合わせた超音波は,試験管内および動物モデルにおいて,凝固溶解を著しく強化した. この非侵襲的アプローチは,血栓解消剤治療の有効性を向上させる可能性があります.
科学分野:
- バイオメディカルエンジニアリング
- 心血管研究 循環器科の研究
- 医学物理 医学物理学
背景:
- 組織型プラズミノゲン活性化剤 (t-PA) などの血栓解消剤の結合部位が限られているため,フィブリノリチクセラピーの有効性は制限されています.
- トロンボリシス中の超音波曝露は,t-PA.のより多くの結合部位を暴露することによって,凝固溶解を高める可能性があります.
研究 の 目的:
- トロンボリーシスを強化する超音波の可能性を調査する.
- 超音波とt-PAが凝固溶解に及ぼす共同効果を in vitro および in vivo で評価する.
主な方法:
- 放射性標識されたフィブリノゲンを含んだヒトの血栓は,断続的な超音波 (1MHz,1.75W/cm2) を伴い,または伴わず,さまざまな濃度のt-PAをインキュベートした.
- ウサギの動脈血栓形成モデルを使用して,t-PA単独の溶解と超音波によるt-PAを比較しました.
主要な成果:
- 超音波は,すべてのt-PA濃度において,凝固溶解を in vitro で有意に増加させた (p < 0.001).
- 300 IU/mlのt-PAで,超音波は溶解を42%から64%まで増加させた.
- ウサギでは,t-PAによる超音波で100分後に55%の溶解を達成し,t-PA単独では30%であった.
結論:
- 断続的な超音波は,t-PA誘発の血栓溶解を in vitro で著しく強化する.
- 超音波は,動物の血栓形成モデルにおいて,強化された溶解への傾向を示した.
- 非侵襲的中断性超音波は,血栓解消療法に貴重な補助剤として役立つ可能性があります.
さらに関連する動画
関連する概念動画
01:17Intracellular Signaling Affects Focal Adhesions
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
01:18Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Oral anticoagulants are vital tools in preventing and treating blood clotting disorders. This diverse class of medications can be categorized as vitamin K antagonists, exemplified by warfarin, and direct thrombin inhibitors (DTIs), such as dabigatran, as well as factor Xa inhibitors, including rivaroxaban.
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
01:22Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
01:30Factors Affecting Drug Distribution: Tissue Permeability
The drug distribution process within the human body is a complex interplay of various physicochemical properties inherent to the drugs. These properties, including molecular size, ionization degree, partition coefficient, and stereochemical nature, significantly impact how drugs permeate biological membranes to reach their target tissues.
Small molecules with a molecular weight below 500 to 600 Daltons can easily pass through the capillary membrane, gaining access to different tissues. Larger...
Small molecules with a molecular weight below 500 to 600 Daltons can easily pass through the capillary membrane, gaining access to different tissues. Larger...
01:25Bioactivation and Tissue Toxicity
Bioactivation is a metabolic process that transforms less reactive substances into highly reactive metabolites, initiating tissue toxicity. This transformation can lead to various toxic effects, including carcinogenesis and teratogenesis. Reactive metabolites are classified into two main types: electrophiles and free radicals.Electrophiles are electron-deficient species and are produced primarily by the enzyme cytochrome P-450 during the metabolism of compounds containing carbon, nitrogen, or...