Motivation: Extracellular vesicles (EVs) are spherical bilayered proteolipids, harboring various bioactive molecules. Due to the complexity of the vesicular nomenclatures and components, online searches for EV-related publications and vesicular components are currently challenging. Results: We present an improved version of EVpedia, a public database for EVs research. This community web portal contains a database of publications and vesicular components, identification of orthologous vesicular components, bioinformatic tools and a personalized function. EVpedia includes 6879 publications, 172 080 vesicular components from 263 high-throughput datasets, and has been accessed more than 65 000 times from more than 750 cities. In addition, about 350 members from 73 international research groups have participated in developing EVpedia. This free web-based database might serve as a useful resource to stimulate the emerging field of EV research. Availability and implementation: The web site was implemented in PHP, Java, MySQL and Apache, and is freely available at http://evpedia.info. Contact:ysgho@postech.ac.kr

Summary: Due to low bioavailability and high inter-individual variability, monitoring of dabigatran may be required in specific situations to prevent the risk of bleedings or thrombosis. The aim of the study was to determine which coagulation assay(s) could be used to assess the impact of dabig-atran on secondary haemostasis. Dabigatran was spiked at concentrations ranging from 4.7 ng/ml to 943.0 ng/ml in pooled citrated human platelet-poor plasma. The following clotting assays were performed: prothrombin time (PT); activated partial thromboplastin time (aPTT); thrombin time (TT); ecarin clotting time (ECT); ecarin chromo-genic assay (ECA); prothrombinase-induced clotting time (PiCT); activated clotting time (ACT); Hemoclot Thrombin Inhibitor (HTI) and thrombin generation assay (TGA). A concentration-dependent prolongation of PT, dPT, and aPTT was observed with aPTT being the more sensitive test. The results varied mostly due to the clotting reagent. HTI, ECT and TGA were the most sensitive tests but are not available 24 hours a day. In addition, HTI showed a linear correlation with a good reproduci-bility. Dabigatran induced a concentration-dependent delay and inhibition of tissue factor-induced TGA. Cut-offs related with higher risk of bleedings or thrombosis were defined for each reagent of aPTT and HTI. In conclusion, aPTT could be used for the monitoring of dabigatran and as screening test for the risk of overdose. However, because of its higher sensitivity, good reproducibility, excellent linear correlation at all doses, its simplicity of use, and possibilities of automation, HTI should be considered as the gold-standard.

D-dimer is a soluble fibrin degradation product deriving from the plasmin-mediated degradation of cross-linked fibrin. D-dimer can hence be considered a biomarker of activation of coagulation and fibrinolysis, and it is routinely used for ruling out venous thromboembolism (VTE). D-dimer is increasingly used to assess the risk of VTE recurrence and to help define the optimal duration of anticoagulation treatment in patients with VTE, for diagnosing disseminated intravascular coagulation, and for screening medical patients at increased risk of VTE. This review is aimed at (1) revising the definition of D-dimer; (2) discussing preanalytical variables affecting the measurement of D-dimer; (3) reviewing and comparing assay performance and some postanalytical variables (e.g. different units and age-adjusted cutoffs); and (4) discussing the use of D-dimer measurement across different clinical settings.

Summary: Apixaban does not require monitoring nor frequent dose adjustment. However, searching for the optimal dose for the individual patient may be useful in some situations. Moreover, there is a need for clinicians to know whether coagulation assays are influenced by apixaban use. The aim of this study was to determine which coagulation assay could be used to assess the impact of apixaban on haemostasis and provide good laboratory recommendations for the accurate interpretation of haemostasis assays. Apixaban is spiked at concentrations ranging from 5 to 500 ng/ml in platelet-poor plasma. Routinely used or more specific coagulation assays are tested. Results show a concentration dependent prolongation of aPTT, PT and dilute PT. The sensitivity mainly depends on the reagent, but none of these tests is sensitive enough to ensure an accurate estimation of the pharmacodynamic effect of apixaban. FXa chromogenic assays show high sensitivity and a linear correlation depending on the reagent and/or the methodology. Immunological assays and assays acting below the FXa are not influenced by apixaban. In conclusion, PT and/or dilute PT cannot be used to assess apixaban pharmacodynamic properties. More specific and sensitive assays such as chromogenic FXa assays using specific calibrators are required. In case of thrombophilia or in the exploration of a haemorrhagic event, immunological assays should be recommended, when applicable. Standardisation of the time between the last intake of apixaban and the sampling is mandatory.

Several studies reported on the humoral response in subjects having received the BNT162b2 mRNA COVID-19 vaccine. However, data on the kinetics of antibodies 3 months post-vaccination are currently ...