The relaxation of (1)H nuclei due to their interaction with quadrupolar (14)N nuclei in gel structures is measured using fast field-cycling NMR. This phenomenon called quadrupolar dips has been reported in different (1)H-(14)N bond-rich species. In this study, we have studied quadrupolar dips in fibrin, an insoluble protein that is the core matrix of thrombi. Fibrin was formed by the addition o...

Vascular disease accounts for more than 50% of deaths and in most cases the cause lies in obstruction to blood flow by the twin perils of atheroma formation and thrombosis. The major constituents of thrombi are platelets and fibrin, together with trapped red cells and other elements. Our main antithrombotic drugs are the antiplatelet agents to prevent platelets sticking together; anticoagulants...

BACKGROUND AND PURPOSE Approximately 30% of strokes are cryptogenic despite an exhaustive in-hospital work-up. Analysis of clot composition following endovascular treatment could provide insight into stroke etiology. T-cells already have been shown to be a major component of vulnerable atherosclerotic carotid lesions. We therefore hypothesize that T-cell content in intracranial thrombi may also...

Thromboembolic disease is a leading cause of morbidity and mortality worldwide. In the last several years there have been a number of studies attempting to identify mechanisms that stop thrombus growth. This paper identifies a novel mechanism related to formation of a fibrin cap. In particular, protein transport through a fibrin network, an important component of a thrombus, was studied by inte...

Thrombi and thromboemboli are organized fibrin clots that may result in partial or total occlusion of arterial or venous blood flow. Consequences of occlusion of blood flow vary with the organ affected.Thrombolytic agents have been used for the dissolution of pathologic thrombi since the 1980s. While similar in their mechanisms of action and side effects, these agents differ in their specificit...

The effect of heparin on thrombogenesis induced by the subendothelium of rabbit aorta was investigated in 24 healthy volunteers after intravenous injection of different doses (0, 1000, 2500, and 5000 IU). By using an ex vivo perfusion chamber system, the interaction between flowing blood and exposed subendothelium was measured at low (50 s-1), intermediate (650 s-1), and high (2600 s-1) wall sh...

Coronary thrombolysis with t-PA is generally implemented with concomitant administration of heparin. However, results of studies in vitro suggest that heparin competes with fibrin for binding of tissue-type plasminogen activator (t-PA), augments activation of free plasminogen, decreases fibrin specificity, and impairs thrombolysis. To define the biological implications of these observations, we...

Arterial thrombi and atherosclerotic lesions were analyzed immunochemically and examined histologically. The extent of in vivo proteolytic cleavage of the amino-terminal end of fibrinogen by thrombin and plasmin was determined and quantitated by specific radioimmunoassays. The samples were treated with cyanogen bromide (CNBr), and the total amount of fibrinogen and fibrin-derived protein was de...

T relationship among platelet survival, vessel injury, and thrombosis is of interest because of the role that platelets play in the development of atherosclerosis and its thromboembolic complications. Blood platelets do not adhere to normal endothelium. However, when a blood vessel is injured, platelets adhere to the injury site and, if blood flow is disturbed, thrombi can form on the injured a...

Activated platelets provide assembly sites for coagulation enzyme complexes and in this way can mediate coagulation during hemostasis and thrombosis. In this study, we examined the procoagulant activity of platelets adhering directly to fibrillar collagen, a main thrombogenic constituent of subendothelium. For this purpose, we used a human ex-vivo thrombosis model in which collagen-coated cover...