Thrombin Substrates? A1: Fibrinogen. Converted to Fibrin. Fibrin monomers polymerize to fibrin clot.

Thrombin Substrates? A1-part 2: Fibrinogen. Fibrinogen is also substrate for platelet binding through gpIIbIIIa receptor.

This anticoagulant medication is a pentasaccharide that will interact with antithrombin and inhibit Factor10a and F9a. Name it.

Fondaparinux. In the unlikely event that a level will be checked, 3 hours post dose is suggested (as compared to 4 hours post dose for LMWH)

Back to Thrombin Substrates. A2/A3: Factors 5 & 8 (the critical cofactors of Factors 10 & 9). Primary amplification for thrombin generation

Thrombin Sbstrt A4=F11.Thrombin activation of F11 maintains thrombin generation following major injury and in tissues with high fibrinolysis

Welcoming new Trainees at UCSF for another year! Coag tweets to follow!!

Factor inhibitors can be quantified in Bethesda Units. Patient & Normal plasma are mixed. 1 BU = Amount that inhibits half of Factor present

A surprising aspect of vWD is that the null alleles associated with type 3 do not cause type 1 when they are heterozygous: 50% VWF is enough

Thrombin time= underutilized test. Terrific for picking up presence of thrombin inhibitors: heparin, DTIs, paraneoplastic heparinoid.

vWD Dx point: If vWF Ristocetin cofactor activity: vWF antigen ratio is low, this can reflect type 2A, 2B, or 2M.

What's wrong with high molecular weight vWF multimers in 2A/2B/2M (simplified)? A=absent, B=bound (to plts), M=messed up (don't bind plts)

I would like to welcome all the new residents to UCSF's Anatomic and Clinical Pathology Program. Do you recognize this cell?

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Thrombin (Factor 2) = center of the coagulation universe! How does thrombin get activated? How many substrates of thrombin can you name?

When a vessel is damaged, Tissue Factor-Factor 7 (F7) complex activates F10 which activates Prothrombin to Thrombin...just a bit at first

Full activation of thrombin depends on thrombin activating two of its substrates: Factor 8 and Factor 5.

Tissue Factor-F7 activates a bit of F9 and F10. F8a-F9a powerfully activates more F10. F5a-F10a powerfully activates thrombin.

Thrombin Substrates: So far I mentioned F5 and F8. Other key substrates include Fibrinogen, Platelets, Factor 13 & Protein C.

Also important but less discussed substrates of thrombin include Factor 11 (eleven) and TAFI (Thrombin activatable fibrinolysis inhbitor)