Interpreting high levels of unfolded Von Willebrand Factor in patients with the antiphospholipid syndrome.

Introduction: Unfolded Von Willebrand Factor (VWF) is increased in thrombotic pathologies such as myocardial infarction. Unfolded VWF mediates the binding of platelets without the need for collagen. β-glycoprotein I (β-GPI) is a natural inhibitor of the platelet-VWF interaction.

Thrombomodulin is a stronger indicator of combined oral contraceptives-induced activated protein C pathway resistance in the thrombin generation test than activated protein C.

Background: The mechanism by which combined oral contraceptives (COCs) lead to hypercoagulation is not fully understood, although activated protein C (APC) pathway resistance has been implicated. APC and thrombomodulin (TM) tend to be considered as interchangeable reagents, even though their biological action in coagulation is different. However, it remains unclear which reagent is better suited for the detection of APC pathway resistance.

Low thrombin inactivation capacity is associated with an increased risk of recurrent ischemic events after ischemic stroke at a young age.

Background: Patients with ischemic stroke at a young age (18-50 years) have an increased long-term risk of recurrent ischemic events. Hypercoagulability may contribute to this high risk.

Objectives: To investigate the associations between in vivo and ex vivo hemostatic parameters and recurrent ischemic events after an ischemic stroke or transient ischemic attack (TIA) at a young age.

Impaired whole blood thrombin generation is associated with procedure-related bleeding in acutely decompensated cirrhosis.

Background & Aims: The clinical utility of thrombomodulin-modified thrombin generation (TM-TG) in cirrhosis is uncertain. We conducted a prospective study to evaluate the prognostic value of TM-TG in cirrhosis.

Methods: Patients were recruited during outpatient clinics (compensated and stable decompensated) or if admitted to our inpatient service (acutely decompensated, AD).

Functionally distinct anticoagulant mechanisms of endothelial cells.

Antithrombin and tissue factor pathway inhibitor (TFPI) provide different anticoagulant mechanisms. Having established a potent anticoagulant role of cultured human umbilical vein endothelial cells in vessel-on-a-chip microfluidic models, we now investigated how these cells modulated thrombin generation under stasis through antithrombin and TFPI pathways. We observed that endothelial monolayers in 96 well-plates strongly delayed and suppressed the thrombin generation process induced by tissue factor, regardless of the presence of whole blood, platelet-rich plasma or platelet-free plasma.