scholarly journals Microparticles and Nucleosomes Are Released From Parenchymal Cells Destroyed After Injury in a Rat Model of Blunt Trauma

2020 ◽  
Vol 26 ◽  
pp. 107602962095082
Author(s):  
Mineji Hayakwa ◽  
Takayoshi Ooyasu ◽  
Yoshihiro Sadamoto ◽  
Tomoyo Saito ◽  
Tomonao Yoshida ◽  
...  
Keyword(s):  
Creatine Kinase ◽  
Blunt Trauma ◽  
Thrombin Generation ◽  
In Vitro Study ◽  
Coagulation Factors ◽  
Coagulation Cascade ◽  
Trauma Severity ◽  
Time To Initiation ◽  
Parenchymal Cells

We investigated the relationships between circulating procoagulants and trauma severity, including cellular destruction, and the effects of thrombin generation on procoagulants in a rat blunt trauma model. The rats were subjected to tumbling blunt trauma, where they were tumbled for 0, 250, 500, or 1000 revolutions. Creatine kinase, nucleosome, and microparticle plasma levels increased gradually with trauma severity. Strong interrelationships were observed among creatine kinase, nucleosome, and microparticle levels. Time to initiation of thrombin generation shortened with increasing trauma severity. In accordance with trauma severity, prothrombin activity decreased, but the thrombin generation ratio increased. Time to initiation of thrombin generation and the thrombin generation ratio correlated with creatine kinase levels. In an in vitro study, a homogenized muscle solution, which included massive nucleosomes and microparticles, showed accelerated thrombin generation of plasma from healthy subjects. Procoagulants, such as microparticles and nucleosomes, are released from destroyed parenchymal cells immediately after external traumatic force, activating the coagulation cascade. The procoagulants shorten the time to initiation of thrombin generation. Furthermore, although coagulation factors are consumed, the thrombin generation ratio increases.

Effect of Argatroban versus Recombinant Hirudin on Tissue-Factor-Mediated Thrombin Generation: An in Vitro Study

2008 ◽  
Vol 34 (S 01) ◽  
pp. 087-090
Author(s):  
Meyer Samama ◽  
Léna Le Flem ◽  
Céline Guinet ◽  
François Depasse
Keyword(s):  
Tissue Factor ◽  
Thrombin Generation ◽  
In Vitro Study ◽  
Vitro Study ◽  
Recombinant Hirudin

In vitro effects of human neutrophil cathepsin G on thrombin generation: Both acceleration and decreased potential

2010 ◽  
Vol 104 (09) ◽  
pp. 514-522 ◽  
Author(s):  
Thomas Lecompte ◽  
Agnès Tournier ◽  
Lise Morlon ◽  
Monique Marchand-Arvier ◽  
Claude Vigneron ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Thrombin Generation ◽  
Time Course ◽  
Anticoagulant Activity ◽  
Cathepsin G ◽  
Coagulation Cascade ◽  
Clotting Factor ◽  
Factor V ◽  
Clotting Factors

SummaryCathepsin G (Cath G), a serine-protease found in neutrophils, has been reported to have effects that could either facilitate or impede coagulation. Thrombin generation (CAT method) was chosen to study its overall effect on the process, at a plasma concentration (240 nM) observed after neutrophil activation. Coagulation was triggered by tissue factor in the presence of platelets or phospholipid vesicles. To help identify potential targets of Cath G, plasma depleted of clotting factors or of inhibitors was used. Cath G induced a puzzling combination of two diverging effects of varying intensities depending on the phospholipid surface provided: accelerating the process under the three conditions (shortened clotting time by up to 30%), and impeding the process during the same thrombin generation time-course since thrombin peak and ETP (total thrombin potential) were decreased, up to 45% and 12%, respectively, suggestive of deficient prothrombinase. This is consistent with Cath G working on at least two targets in the coagulation cascade. Our data indicate that coagulation acceleration can be attributed neither to platelet activation and nor to activation of a clotting factor. When TFPI (tissue factor pathway inhibitor) was absent, no effect on lag time was observed and the anticoagulant activity of TFPI was decreased in the presence of Cath G. Consistent with the literature and the hypothesis of deficient prothrombinase, experiments using Russel’s Viper Venom indicate that the anticoagulant effect can be attributed to a deleterious effect on factor V. The clinical relevance of these findings deserves to be studied.

Impaired Haemostasis by Intravenous Administration of a Gelatin-based Plasma Expander in Human Subjects

1998 ◽  
Vol 79 (02) ◽  
pp. 286-290 ◽  
Author(s):  
M. Levi ◽  
F. Berends ◽  
A. E. van der Ende ◽  
J. W. ten Cate ◽  
C. P. Stoutenbeek ◽  
...  
Keyword(s):  
Thrombin Generation ◽  
Human Subjects ◽  
Fold Increase ◽  
Coagulation Factors ◽  
Platelet Glycoprotein ◽  
Plasma Expander ◽  
Plasma Substitute ◽  
Significant Impairment ◽  
Randomised Controlled

SummaryThe aim of this study was to investigate the effects of a gelatin-based plasma expander on blood coagulation and haemostasis in human subjects.Six healthy men were studied in a randomised, controlled cross-over study to investigate the effects of a 60 min intravenous infusion of either 1 l gelatin-based plasma substitute (Gelofusine) or 0.9% NaCl (control). The infusion of gelatin resulted in a 1.7 fold increase in bleeding time at 60 min and a 1.4 fold increase at 120 min, while saline had no effect (p <0.05). Aggregation studies revealed a significant impairment of ristocetin-induced platelet aggregation (p <0.05), associated with a substantial decrease of vWF:ag (–32% vs. –5%, p <0.05) and ristocetin co-factor (–29% vs. +1%, p <0.05) and without in vitro impairment of the platelet glycoprotein 1b receptor. Gelatin caused a decrease in thrombin-antithrombin complexes (–45% vs. –4%, p <0.05) and F1+2 (–40% vs. +1%, p <0.05). The decrease in circulating levels of vWF:ag, vWF R:Co, thrombin-antithrombin complexes and F1+ 2 was more than could be expected by the calculated plasma-dilution generated by Gelofusine.Our results demonstrated that the administration of a gelatin-based plasma substitute results in a significant impairment of primary haemostasis and thrombin generation. The defect in primary haemostasis appears to be related to a gelatin-induced reduction in von Willebrand factor, whereas the decreased thrombin generation may be due to the dilution of coagulation factors induced by Gelofusine.

scholarly journals CHOICE OF BLOOD FOR EXCHANGE TRANSFUSION (ET) IN THE NEONATE: IN VITRO STUDY OF COAGULATION FACTORS AND MICROAGGREGATES

1977 ◽  
Vol 11 (4) ◽  
pp. 467-467
Author(s):  
Dorothy R Barnard ◽  
Robert G Chapman ◽  
Michael A Simmons ◽  
William E Hathaway
Keyword(s):  
Exchange Transfusion ◽  
In Vitro Study ◽  
Coagulation Factors ◽  
Vitro Study

scholarly journals Antiplatelet drugs and generation of thrombin in clotting blood

Blood ◽  
1992 ◽  
Vol 80 (8) ◽  
pp. 2006-2011 ◽  
Author(s):  
A Szczeklik ◽  
M Krzanowski ◽  
P Gora ◽  
J Radwan
Keyword(s):  
Oral Administration ◽  
Thrombin Generation ◽  
Ex Vivo ◽  
Coagulation Factors ◽  
Antiplatelet Drugs ◽  
Specific Marker ◽  
Rate Of Increase ◽  
Synthase Inhibitor ◽  
Thrombin Formation

Abstract Platelets participate in formation of thrombin through secretion of coagulation factors and by providing a catalytic surface on which prothrombinase complex is assembled. We studied the effects of four antiplatelet drugs on thrombin formation in healthy volunteers. Thrombin generation was monitored both in vitro--in recalcified plasma-- and ex vivo--in blood emerging from a standardized skin microvasculature injury, which also served to determine bleeding time. A mathematical model has been developed to describe the latter reaction. It is based on estimation of the rate of increase in fibrinopeptide A (FPA), a specific marker of thrombin activity, in blood emerging from skin incisions. Two hours after the ingestion of 500 mg of aspirin, thrombin formation became significantly impaired both in vitro and ex vivo. In contrast, 2 hours after the oral administration of placebo, indomethacin 50 mg, or OKY-046 (a thromboxane synthase inhibitor) 400 mg, thrombinogenesis remained unaltered. Ticlopidine, studied either 3 hours after 500 mg oral administration, or after 5 days of intake at a daily dose of 500 mg, had no effect on thrombin generation. Thus, aspirin, contrary to other antiplatelet drugs, depresses thrombin formation in clotting blood, a phenomenon that might be of clinical relevance. It is suggested that aspirin exerts this effect by acetylating prothrombin and/or macromolecules of platelet membrane.

scholarly journals Monitoring Compound-Related Effects on Coagulability in Rats and Cynomolgus and Rhesus Monkeys by Thrombin Generation Kinetic Measurement

2020 ◽  
Vol 39 (3) ◽  
pp. 207-217
Author(s):  
F. Poitout-Belissent ◽  
D. Culang ◽  
D. Poulin ◽  
R. Samadfan ◽  
S. Cotton ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Thrombin Generation ◽  
In Vivo Studies ◽  
Coagulation Cascade ◽  
Dependent Manner ◽  
Kinetic Assay ◽  
Thrombin Generation Assay ◽  
Coefficients Of Variation

Thrombin generation assay (TGA) is a sensitive method for the assessment of the global clotting potential of plasma. This kinetic assay can detect both hypocoagulable and hypercoagulable conditions: delayed or reduced thrombin generation leading to a prolonged clotting time, or induced thrombin activity, shifting the coagulation cascade toward thrombosis. The purpose of this study is to qualify the TGA in nonhuman primates (NHP) and rats for its use during nonclinical in vivo and in vitro studies. Blood was drawn from nonanesthetized animals, and platelet-poor plasma was obtained after double centrifugation; coefficients of variation were <10% for all derived parameters of thrombin generation assessed with 5 pM of tissue factor. Thrombin generation was evaluated in vitro in rat and NHP plasmas with ascending doses of unfractionated heparin (UFH), recombinant tissue factor, and anticoagulant compounds. Thrombin generation was decreased with UFH and anticoagulant compounds, but was increased in the presence of tissue factor, in a dose-dependent manner. In a rat model of inflammation, animals were administered a low dose of lipopolysaccharides. Thrombin generation measurements were decreased 3 hours post-LPS administration with a nadir at 24 hours, while thrombin–antithrombin complexes reached a peak at 8 hours, supporting an earlier production of thrombin. In conclusion, these data demonstrated that TGA can be performed in vitro for screening of compounds expected to have effects on coagulation cascade, and thrombin generation can be measured at interim time points during nonclinical in vivo studies in rats and NHP.

Abstract 613: In Vitro Microvessels to Study the Platelet-Endothelium Interface

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Jevgenia Zilberman-Rudenko ◽  
Andrew D Wong ◽  
Daniel E Sallee ◽  
Stephanie E Reitsma ◽  
Cristina Puy ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Thrombin Generation ◽  
Vascular Diseases ◽  
Coagulation Factors ◽  
Flow Chamber ◽  
Physical Parameters ◽  
Interstitial Flow ◽  
Disease States ◽  
Blood Flow Dynamics

Background: Under normal conditions, endothelial cells (ECs) govern blood flow dynamics including providing a barrier between blood and tissue and regulating platelet aggregation and thrombin generation in the bloodstream. In turn, blood components, primarily platelets and coagulation factors such as thrombin, regulate EC barrier integrity. The breakdown of EC barrier function is a hallmark of a variety of vascular diseases. In sepsis, for example, the dysfunction of vascular ECs has been correlated with poorer outcomes due to hemorrhage and multi-organ failure associated with consumption of platelets and coagulation factors into clots within the microcirculation, a condition termed disseminated intravascular coagulation (DIC). Aim: Develop an endothelialized flow chamber to study the platelet-endothelium interface. Methods and Results: We developed a 3D-chamber with a perfuseable cylindrical microvessel embedded in an extracellular matrix (ECM) material. This model allows for the study of the role of thrombin generation and platelet aggregation in endothelial barrier leak development and repair in healthy as well as inflamed microvessels. Incorporation of subendothelial matrix proteins in these 3D-microvessel devices expands the capacity of the microfluidic studies to investigate blood cell extravasation and enables the control of physical parameters such as transmural pressure and interstitial flow through the ECM. Conclusion: This model may provide insight into the pathophysiology of different disease states and serve as an expedient platform for therapy design and testing. The platelet-endothelium interface under shear flow. Diagram ( A ) and an experimental prototype ( B ) of a 3D-perfuseable device. Microvessel phenotype (following treatment with vehicle or 10 ng/mL TNFα) pre- and post- perfusion with recalcified whole blood for 33 min as visualized by differential interference contrast, DIC, ( C ) and fluorescence microscopy ( D ).

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