超声波对组织类型等离子体激活剂诱导的血栓溶解的影响
1Department of Hematology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
Circulation
|October 1, 1992
概括
超声波与组织型等离子体激活剂 (t-PA) 结合,在试验室和动物模型中显著增强了凝块溶解. 这种非侵入性方法可能会提高血栓消毒疗法的有效性.
科学领域:
- 生物医学工程 生物医学工程
- 心血管研究研究心血管研究
- 医学物理 医学物理
背景情况:
- 纤维溶解剂治疗的有效性受限于血栓溶解剂的有限结合部位,例如组织类型的等离子体激活剂 (t-PA).
- 血栓溶解期间的超声波暴露可能通过暴露更多的t-PA结合部位来增强血栓溶解.
研究的目的:
- 调查超声波增强血栓溶解的潜力.
- 为了评估超声波和t-PA对凝块溶解的联合作用,在体外和体内.
主要方法:
- 具有放射性标记纤维素的人类血块与t-PA的不同度被化,有或没有间歇性超声波 (1MHz,1.75W/cm2).
- 使用子关静脉血栓形成模型,将单独使用t-PA的溶解与超声波的t-PA进行比较.
主要成果:
- 超声波在体外所有t-PA度上显著增加了凝块溶解 (p < 0.001).
- 在300 IU/ml的t-PA下,超声波将溶解量从42%增加到64%.
- 在子中,使用t-PA的超声波在100分钟内实现了55%的溶解,而仅使用t-PA则达到30%;仅用超声波显示了最小的溶解 (6%).
结论:
- 间歇性超声波在体外显著增强t-PA诱导的血栓溶解.
- 超声波显示在动物血栓形成模型中,增强溶解的趋势.
- 非侵入性间歇性超声波可以作为血栓消毒疗法的宝贵补充剂.
相关概念视频
Intracellular 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...
Anticoagulant 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...
Anticoagulant 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...
Formation 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...
Factors 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...
Bioactivation 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...


