3:09 PM Abstract No. 176 Effect of acoustic pulses on fibrin structure in clots

SummaryInteractions between tranexamic acid and protein were studied in respect of the antifibrinolytic actions of tranexamic acid. Tranexamic acid did neither show any interaction with fibrinogen or fibrin, nor was incorporated into cross-linked fibrin structure by the action of factor XIII. On the other hand, tranexamic acid bound to human plasmin with a dissociation constant of 3.5 × 10−5 M, which was very close to the inhibition constant (3.6 × 10−5 M) for this compound in inhibiting plasmin-induced fibrinolysis. The binding site of tranexamic acid on plasmin was not the catalytic site of plasmin, because TLCK-blocked plasmin also showed a similar affinity to tranexamic acid (the dissociation constant, 2.9–4.8 × 10−5 M).In the binding studies with the highly purified plasminogen and TLCK-plasmin preparations which were obtained by affinity chromatography on lysine-substituted Sepharose, the molar binding ratio was shown to be 1.5–1.6 moles tranexamic acid per one mole protein.On the basis of these and other findings, a model for the inhibitory mechanism of tranexamic acid is presented.

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Fibrin clot structure in patients with end-stage renal disease

Thrombosis and Haemostasis ◽

10.1160/th06-12-0715 ◽

2007 ◽

Vol 98 (08) ◽

pp. 339-345 ◽

Cited By ~ 42

Author(s):

Johannes Sidelmann ◽

Mikkel Brabrand ◽

Robert Pedersen ◽

Jørgen Pedersen ◽

Kim Esbensen ◽

...

Keyword(s):

Renal Disease ◽

End Stage Renal Disease ◽

Healthy Controls ◽

Structure Characteristics ◽

Stage Renal Disease ◽

End Stage ◽

Esrd Patients ◽

Fibrin Structure ◽

Plasma Markers ◽

Fibrin Clots

SummaryFibrin clots with reduced permeability, increased clot stiffness and reduced fibrinolysis susceptibility may predispose to cardiovascular disease (CVD). Little is known, however, about the structure of fibrin clots in patients with end-stage renal disease (ESRD).These patients suffer from a high risk of CVD in addition to their chronic low-grade inflammation. Using permeability, compaction and turbidity studies in 22 ESRD patients and 24 healthy controls, fibrin clots made from patient plasma were found to be less permeable (p<0.001), less compactable (p<0.001), and less susceptible to fibrinolysis (p<0.001) than clots from controls.The maximum rate of turbidity increase was also higher for the patients than controls (p<0.001), and scan-ning electron microscopy revealed higher clot density of fibrin fibers in clots from patients than clots from controls (p<0.001). Patients had higher plasma concentrations of fibrinogen, C-reative protein and interleukin 6 than controls.These plasma markers of inflammation correlated significantly with most of the fibrin structure characteristics observed in the patients. In contrast, plasma markers of azothemia showed no such correlations. The results suggest that in ESRD patients fibrin clots are significantly different from healthy controls, and that the fibrin structure characteristics in the patients are associated primarily with the inflammatory plasma milieu rather than with level of azothemia.

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Regeneration of the Filtrable Forms of Salmonella enteritidis in Media containing Blood Plasma (Fibrin Structure)

Nature ◽

10.1038/176208a0 ◽

1955 ◽

Vol 176 (4474) ◽

pp. 208-209 ◽

Cited By ~ 1

Author(s):

I. JUHÁSZ ◽

J. VADÁSZ

Keyword(s):

Blood Plasma ◽

Salmonella Enteritidis ◽

Fibrin Structure

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Study on fibrin structure under various experimental conditions.

Blood & Vessel ◽

10.2491/jjsth1970.17.144 ◽

1986 ◽

Vol 17 (2) ◽

pp. 144-146

Author(s):

Hiroko SATO

Keyword(s):

Experimental Conditions ◽

Fibrin Structure

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Factor XIIa regulates the structure of the fibrin clot independently of thrombin generation through direct interaction with fibrin

Blood ◽

10.1182/blood-2011-03-339572 ◽

2011 ◽

Vol 118 (14) ◽

pp. 3942-3951 ◽

Cited By ~ 84

Author(s):

Joke Konings ◽

José W. P. Govers-Riemslag ◽

Helen Philippou ◽

Nicola J. Mutch ◽

Julian I. Borissoff ◽

...

Keyword(s):

Thrombin Generation ◽

Thrombus Formation ◽

Coagulation Factor ◽

Direct Interaction ◽

Fibrin Clot ◽

Fiber Density ◽

Contact Pathway ◽

Clot Structure ◽

Fibrin Structure

Abstract Recent data indicate an important contribution of coagulation factor (F)XII to in vivo thrombus formation. Because fibrin structure plays a key role in clot stability and thrombosis, we hypothesized that FXII(a) interacts with fibrin(ogen) and thereby regulates clot structure and function. In plasma and purified system, we observed a dose-dependent increase in fibrin fiber density and decrease in turbidity, reflecting a denser structure, and a nonlinear increase in clot stiffness with FXIIa. In plasma, this increase was partly independent of thrombin generation, as shown in clots made in prothrombin-deficient plasma initiated with snake venom enzyme and in clots made from plasma deficient in FXII and prothrombin. Purified FXII and α-FXIIa, but not β-FXIIa, bound to purified fibrinogen and fibrin with nanomolar affinity. Immunostaining of human carotid artery thrombi showed that FXII colocalized with areas of dense fibrin deposition, providing evidence for the in vivo modulation of fibrin structure by FXIIa. These data demonstrate that FXIIa modulates fibrin clot structure independently of thrombin generation through direct binding of the N-terminus of FXIIa to fibrin(ogen). Modification of fibrin structure by FXIIa represents a novel physiologic role for the contact pathway that may contribute to the pathophysiology of thrombosis.

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