Laboratory Identification of Lupus Anticoagulant (LA) Using Different Activated Partial Thromboplastin Time (APTT) Assays.

Introduction: The International Society of Thrombosis and Hemostasis (ISTH) guidelines suggest a three-step evaluation for the detection of lupus anticoagulant (LA), including screening, mixing, and confirmation. According to the guidelines, the LA assay based on activated partial thromboplastin time (APTT) should include an initial screening step followed by a confirmatory step that uses a higher concentration of phospholipids in either bilayer or hexagonal form. For the activator, the guidelines recommend using silica, though ellagic acid is also an option.

Association between extracellular vesicles (EVs) and thrombosis in antiphospholipid syndrome.

BackgroundAntiphospholipid syndrome (APS) is characterized by thrombosis or pregnancy complications associated with the presence of antiphospholipid antibodies (aPLs). Although the exact mechanisms are unclear, aPLs can increase the expression of tissue factor on platelets, leukocytes, and endothelial cells, leading to hypercoagulability. Extracellular vesicles (EVs) can also be released during this process and play a key role in immune regulation and thrombosis related to APS.

Persistent hypofibrinolysis in severe COVID-19 associated with elevated fibrinolysis inhibitors activity.

Hypercoagulability and reduced fibrinolysis are well-established complications associated with COVID-19. However, the timelines for the onset and resolution of these complications remain unclear. The aim of this study was to evaluate, in a cohort of COVID-19 patients, changes in coagulation and fibrinolytic activity through ROTEM assay at different time points during the initial 30 days following the onset of symptoms in both mild and severe cases.

Extracellular vesicles are a late marker of inflammation, hypercoagulability and COVID-19 severity.

Exacerbated inflammation and coagulation are a hallmark of COVID-19 severity. Extracellular vesicles (EVs) are intercellular transmitters involved in inflammatory conditions, which are capable of triggering prothrombotic mechanisms. Since the release of EVs is potentially associated with COVID-19-induced coagulopathy, the aim of this study was to evaluate changes in inflammation- and hypercoagulability-related EVs during the first month after symptom onset and to determine whether they are associated with disease severity.

Anticoagulant Activity of Nucleic Acid Nanoparticles (NANPs) Assessed by Thrombin Generation Dynamics on a Fully Automated System.

Rapidly reversible anticoagulant agents have great clinical potential. Oligonucleotide-based anticoagulant agents are uniquely positioned to fill this clinical niche, as they are able to be deactivated through the introduction of the reverse complement oligo. Once the therapeutic and the antidote oligos meet in solution, they are able to undergo isothermal reassociation to form short, inactive, duplexes that are rapidly secreted via filtration by the kidneys.