Search results for "thrombin generation"
showing 10 items of 15 documents
Clinical Determinants of Thrombin Generation Measured in Presence and Absence of Platelets-Results from the Gutenberg Health Study.
2018
AbstractThe tendency of a plasma sample to generate thrombin, a central enzyme in blood coagulation, might be an important indicator of prothrombotic risk linked to cardiovascular disease (CVD), but the presence of platelets may be a critical determinant. Clinical data, laboratory markers and thrombin generation (TG), investigated in both platelet-rich plasma (PRP) and platelet-free plasma (PFP) at 1 pM TF, were available in 407 individuals from the Gutenberg Health Study. Given the well-known effect of anticoagulants on TG, subjects taking anticoagulants (n = 15) have been excluded resulting in 392 subjects for further analysis. Lag time, endogenous thrombin potential (ETP) and peak height…
Prothrombotic State Induced by Middle-Distance Endurance Exercise in Middle-Aged Athletes
2018
AbstractSince the impact of possible prothrombotic factors on blood coagulation resulting from exercise remains elusive, this study investigated the acute effects of middle-distance endurance running on blood coagulation parameters in middle-aged athletes. The study population consisted of 33 male endurance runners who were engaged in a 21.1 km run under competitive conditions. Blood samples were collected before the run, immediately after the run, and 3 hours after run completion. Samples were assessed for activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen, D-dimer, factor VIII (FVIII), von Willebrand factor antigen (VWF:Ag), endogenous thrombin potential (area…
VITAMIN K-INDUCED MODIFICATION OF COAGULATION PHENOTYPE IN VKORC1 HOMOZYGOUS DEFICIENCY
2008
Summary. Background: Combined vitamin K-dependent clotting factor (VKCF) deficiency type 2 (VKCFD2) is a rare bleeding disorder caused by mutated vitamin K 2,3-epoxide reductase complex subunit 1 (VKORC1) gene. Methods and results: An Italian patient with moderate to severe bleeding tendency was genotyped, and found to be homozygous for the unique VKORC1 mutation (Arg98Trp) so far detected in VKCFD2. The activity levels of VKCFs were differentially reduced, and inversely related to the previously estimated affinity of procoagulant factor propeptides for the γ-carboxylase. The normal (factor IX) or reduced antigen levels (other VKCFs) produced a gradient in specific activities. Vitamin K su…
Buffy coat-derived platelets cryopreserved using a new method: Results from in vitro studies
2018
Abstract Cryopreservation for the long-term storage of platelets (PLTs) is a useful method to overcome the limits of platelet shortage. This is an in vitro prospective study to evaluate the count, viability, and function of buffy coat-derived pooled platelet concentrates (BC-PLTs), treated with dimethyl sulphoxide (DMSO) and cryopreserved (CRY BC-PLTs) at −80 °C with a modified Valeri method. PLTs were stored in 6% DMSO with a patented kit. Overall, 49 BC-PLTs from 245 healthy volunteer donors were prepared, cryopreserved, and analysed before and after 3, 6, and 9 months of storage. In flow cytometry, a statistically significant reduction in CD 42b (92.7 ± 4.29% at T0 vs. 23.6 ± 27.5% at T3…
Platelets Contribution to Thrombin Generation in Philadelphia-Negative Myeloproliferative Neoplasms: The "Circulating Wound" Model.
2021
Current cytoreductive and antithrombotic strategies in MPNs are mostly based on cell counts and on patient’s demographic and clinical history. Despite the numerous studies conducted on platelet function and on the role of plasma factors, an accurate and reliable method to dynamically quantify the hypercoagulability states of these conditions is not yet part of clinical practice. Starting from our experience, and after having sifted through the literature, we propose an in-depth narrative report on the contribution of the clonal platelets of MPNs—rich in tissue factor (TF)—in promoting a perpetual procoagulant mechanism. The whole process results in an unbalanced generation of thrombin and i…
Enhanced thrombin generation in patients with cirrhosis-induced coagulopathy.
2010
Summary. Background: Prothrombin time (PT) and the international normalized ratio (INR) are still routinely measured in patients with liver cirrhosis to ‘assess’ their bleeding risk despite the lack of correlation with the two. Thrombin generation (TG) assays are global assays of coagulation that are showing promise in assessing bleeding and thrombosis risks. Aim: To study the relationship between the INR and TG profiles in cirrhosis-induced coagulopathy. Methods: Seventy-three patients with cirrhosis were studied. All TG parameters were compared with those from a normal control group. Contact activation was prevented using corn trypsin inhibitor. TG was also assayed in the presence of Prot…
Thrombin generation - a potentially useful biomarker of thrombotic risk in Philadelphia-negative myeloproliferative neoplasms.
2017
The diagnosis of essential thrombocythemia and polycythemia vera is often made during a thrombotic event which can be serious. Philadelphia-negative chronic myeloproliferative neoplasia patients have an increased thrombotic risk. This is assessed using various scoring systems but these are far from ideal and individual risk. The currend trend to personalised medicine requires finding the most useful thrombotic risk biomarker in these patients. Routine tests for coagulation do not take account of both pro- and anti-coagulant factors which is why these tests are not useful in patients with Philadelphia-negative myeloproliferative neoplasms. Thrombin generation reflects more accurately the bal…
Clinical Applications, Pitfalls, and Uncertainties of Thrombin Generation in the Presence of Platelets
2019
Platelet-dependent thrombin generation is a helpful tool to assess ex vivo the interaction between platelets and plasma coagulation factors in the initiation, amplification, and inhibition of thrombin generation (TG). This review article discusses the most relevant available data on the clinical applications of fluorogenic TG, the most widely used TG assay, performed in the presence of platelets, i.e., in platelet-rich plasma. With respect to prothrombotic states, arterial hypertension and obesity were the most prominent cardiovascular conditions linked to increased platelet-dependent TG. In addition, platelet-associated hypercoagulability, assessed by the TG assay, has been shown in indivi…
Abstract 147: The Role of Thrombin Generation in Cardiovascular Disease and Mortality - Results from the Population-based Gutenberg Health Study
2018
Background: Thrombin formation is one of the key enzymatic processes that direct the activity of the hemostatic system. Thrombin generation (TG), a method addressing the overall potential of a given plasma sample to form thrombin, may be a potential tool to improve risk stratification for cardiovascular diseases (CVD). This study aims to explore the relation between TG and cardiovascular risk factors (CVRFs), CVD, and total mortality. Methods: For this study, N=5000 subjects from the population-based Gutenberg Health Study were analyzed in a highly standardized setting. TG was measured by the Calibrated Automated Thrombogram method at 1 and 5 pM tissue factor (TF) trigger in platelet poor …
Evaluation of thrombin generation in classical Philadelphianegative myeloproliferative neoplasms / Evaluarea generării trombinei în neoplasmele mielo…
2016
Abstract Introduction: Patients with Philadelphia-negative chronic myeloproliferative neoplasms (Ph-MPN), polycytemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis (PMF), are prone to develop thrombotic events. We aimed to investigate the coagulation status in their plasma using thrombin generation assay (TGA), a functional global assay, on Ceveron® Alpha. Materials and methods: The samples were collected from 89 consecutive Ph-negative MPN patients and from 78 controls into K2EDTA and CTAD tubes for blood cell counts, TGA and coagulation screening tests. Thrombin generation was analysed in platelet-poor plasma using Technothrombin® TGA assay kit. Results: We found a …