Screening and functional exploration of prothrombin Arg596 related mutations in Chinese venous thromboembolism patients

AimsDysfunctional prothrombin residue Arg596 associated mutation has been found to precipitate venous thromboembolism (VTE). In the current study we investigated the prevalence of Arg596 associated mutations in Chinese patients with VTE and explored the functional impact of Arg596Gln mutation on coagulation function in affected patients.MethodsProthrombin clotting activity was measured in 267 unrelated patients with unprovoked VTE. Patients with moderately decreased activities underwent further analysis of the F2 gene. Prothrombin amidolytic activity and antigen levels were detected in mutation carriers. Specific family members were investigated about their VTE histories and clinical phenotypes. The thrombin generation test (TGT) was used to evaluate thrombin function and antithrombin resistance assay was applied to assess the extent of impaired antithrombin inhibition of mutation carriers.ResultsTwo heterozygous mutation carriers of prothrombin Arg596Gln were identified, both of whom had moderately decreased clotting activities but normal amidolytic activities and antigen levels. Among the families of the two probands, nine out of 13 mutation carriers experienced episodes of VTE. TGTs showed that patients had elevated endogenous thrombin potential and prolonged start tail time. Thrombin generation could be inhibited in the presence of thrombomodulin. The thrombin Arg596Gln variant in patients’ plasma presented strong resistance to antithrombin inhibition.ConclusionProthrombin Arg596Gln mutation is a risk factor for Chinese patients with VTE due to its moderately decreased clotting activity but strong resistance to antithrombin inhibition. Prothrombin clotting activity screening and its encoding gene sequencing should be considered in patients with VTE when other established risk factors are absent.

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Thrombin generation in first-degree relatives of patients with venous thromboembolism who have factor V Leiden

Thrombosis and Haemostasis ◽

10.1160/th07-08-0515 ◽

2008 ◽

Vol 99 (01) ◽

pp. 223-228 ◽

Cited By ~ 21

Author(s):

Jèrôme Duchemin ◽

Christophe Leroyer ◽

Bènèdicte Delahousse ◽

Jean François Abgrall ◽

Dominique Mottier ◽

...

Keyword(s):

Venous Thromboembolism ◽

Odds Ratio ◽

Thrombin Generation ◽

Adjusted Odds Ratio ◽

Factor V Leiden ◽

Factor V ◽

Oestrogen Therapy ◽

Prothrombotic State ◽

First Degree Relatives ◽

Generation Test

SummaryThe thrombin generation test appears to be a highly sensitive and specific test in the detection of thrombophilia in patients with venous thromboembolism. We aimed to determine the accuracy of the thrombin generation test to detect factorV Leiden and/or other prothrombotic states in first-degree relatives of patients with venous thromboembolism and factor V Leiden. Sixty-two first-degree relatives of 21 index cases were tested for factor V Leiden, the G20210A prothrombin gene mutation and thrombin generation. Information about oestrogen therapy and previousVTE was also collected. The normalized Thrombomodulin sensitivity ratio (n-TMsr) was defined as the ratio of endogenous thrombin potential determined in the presence and absence of thrombomodulin which was normalized against the same ratio determined in normal control plasma. The mean n-TMsr was 1.37 (± 0.33) in the 45 relatives with one or more prothrombotic state (factor V Leiden, G20210A prothrombin mutation, oestrogen therapy or hormonal therapy) and 1.02 (± 0.34) in the 17 relatives without prothrombotic state (p = 0.001). The positive predictive value was 90.3 (95%CI, 73.1 – 97.4). In relatives with an abnormal n-TMsr, the adjusted odds ratio for having a prothrombotic state was 8.3 (95%CI, 1.9 – 36.9) and the adjusted odds ratio for having the factor V Leiden was 14.3 (95%CI, 2.9 – 71.2).An abnormal thrombin generation test appears highly predictive for having factor V Leiden and/or other prothrombotic states in first-degree relatives of patients with venous thromboembolism and factor V Leiden.

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Experimental Studies on a Recombinant Hirudin, CGP 39393

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648151 ◽

1991 ◽

Vol 65 (04) ◽

pp. 355-359 ◽

Cited By ~ 12

Author(s):

E Gray ◽

J Watton ◽

S Cesmeli ◽

T W Barrowcliffe ◽

D P Thomas

Keyword(s):

Thrombin Generation ◽

Bleeding Time ◽

Thrombus Formation ◽

Experimental Studies ◽

Venous Stasis ◽

Antithrombotic Agent ◽

Recombinant Hirudin ◽

Excessive Bleeding ◽

Generation Test

SummaryThe in vitro anticoagulant activities of recombinant desulphatohirudin (r-hirudin) were studied in the activated partial thromboplastin time (APTT) and the thrombin generation test : systems. In the APTT at concentrations below 5 μg/ml, r-hirudin showed a dose-response curye. At concentrations above 5 μg/ml, the plasma became unclottable, but in the thrombin generation test , at least 10 μg/ml of r-hirudin was required for full inhibition of thrombin generation. The antithrombotic effect was assessed using a rabbit venous stasis model; 150 μg/ml r-hirudin completely prevented thrombus formation at 10 and 20 min stasis. At antithrombotic dose, the mean bleeding time ratio measured in a rabbit ear template model, was not prolonged over control values. At higher doses, the bleeding time ratios were higher than those observed for the same dosage of heparin. These data indicate that while r-hirudin is an effective antithrombotic agent, antithrombotic doses have to be carefully titrated to avoid excessive bleeding.

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The Ability of Thrombin Inhibitors to Reduce the Thrombin Activity Generated in Plasma on Extrinsic and Intrinsic Activation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655996 ◽

1997 ◽

Vol 77 (03) ◽

pp. 498-503 ◽

Cited By ~ 26

Author(s):

D Prasa ◽

L Svendsen ◽

J Stürzebecher

Keyword(s):

Active Site ◽

Thrombin Generation ◽

Anion Binding ◽

Thrombin Inhibitors ◽

Coagulation System ◽

Thrombin Activity ◽

Continuous Registration ◽

High Concentrations ◽

20 Nm ◽

Generation Test

SummaryIn a thrombin generation test with continuous registration of thrombin activity in plasma we studied the ability of a variety of thrombin inhibitors of different type and mechanism of action to influence the activity of thrombin after activation of the coagulation system. Depending on the inhibitor, the peak of thrombin activity is delayed and/or reduced.By blocking the active site of generated thrombin inhibitors cause a concentration dependent reduction of the thrombin peak and inhibit feed-back reactions of thrombin resulting in a delay of thrombin generation. Highly potent synthetic active-site directed inhibitors (Ki ≤ 20 nM) reduce the thrombin activity formed in plasma after extrinsic or intrinsic activation with the same efficiency (IC50 0.1 - 0.6 μM) as hirudin. The delay and reduction of thrombin generation by inhibitors of the anion-binding exosite 1 of thrombin is only attributed to an inhibition of feed-back reactions of thrombin. For a 50% reduction of thrombin activity in plasma by this type of inhibitors relatively high concentrations were determined.

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Levels of Prothrombin Fragment F1+2 in Patients with Hyperhomocysteinemia and a History of Venous Thromboembolism

Thrombosis and Haemostasis ◽

10.1055/s-0038-1665405 ◽

1997 ◽

Vol 78 (05) ◽

pp. 1327-1331 ◽

Cited By ~ 21

Author(s):

Paul A Kyrle ◽

Andreas Stümpflen ◽

Mirko Hirschl ◽

Christine Bialonczyk ◽

Kurt Herkner ◽

...

Keyword(s):

Venous Thromboembolism ◽

Thrombin Generation ◽

Oral Anticoagulant Therapy ◽

Oral Anticoagulants ◽

Control Group ◽

Prothrombin Fragment ◽

Hemostatic System ◽

Significant Difference ◽

System Activation ◽

One Year

SummaryIncreased thrombin generation occurs in many individuals with inherited defects in the antithrombin or protein C anticoagulant pathways and is also seen in patients with thrombosis without a defined clotting abnormality. Hyperhomocysteinemia (H-HC) is an important risk factor of venous thromboembolism (VTE). We prospectively followed 48 patients with H-HC (median age 62 years, range 26-83; 18 males) and 183 patients (median age 50 years, range 18-85; 83 males) without H-HC for a period of up to one year. Prothrombin fragment Fl+2 (Fl+2) was determined in the patient’s plasma as a measure of thrombin generation during and at several time points after discontinuation of secondary thromboprophylaxis with oral anticoagulants. While on anticoagulants, patients with H-HC had significantly higher Fl+2 levels than patients without H-HC (mean 0.52 ± 0.49 nmol/1, median 0.4, range 0.2-2.8, versus 0.36 ± 0.2 nmol/1, median 0.3, range 0.1-2.1; p = 0.02). Three weeks and 3,6,9 and 12 months after discontinuation of oral anticoagulants, up to 20% of the patients with H-HC and 5 to 6% without H-HC had higher Fl+2 levels than a corresponding age- and sex-matched control group. 16% of the patients with H-HC and 4% of the patients without H-HC had either Fl+2 levels above the upper limit of normal controls at least at 2 occasions or (an) elevated Fl+2 level(s) followed by recurrent VTE. No statistical significant difference in the Fl+2 levels was seen between patients with and without H-HC. We conclude that a permanent hemostatic system activation is detectable in a proportion of patients with H-HC after discontinuation of oral anticoagulant therapy following VTE. Furthermore, secondary thromboprophylaxis with conventional doses of oral anticoagulants may not be sufficient to suppress hemostatic system activation in patients with H-HC.

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Faculty Opinions recommendation of Global measurement of coagulation in plasma from normal and haemophilia dogs using a novel modified thrombin generation test - Demonstrated in vitro and ex vivo.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727484052.793532658 ◽

2017 ◽

Author(s):

Coen Hemker

Keyword(s):

Thrombin Generation ◽

Ex Vivo ◽

Generation Test

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Cumulative risks of colorectal cancer in Han Chinese patients with Lynch syndrome in Taiwan

Scientific Reports ◽

10.1038/s41598-021-88289-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Abram Bunya Kamiza ◽

Wen-Chang Wang ◽

Jeng-Fu You ◽

Reiping Tang ◽

Huei-Tzu Chien ◽

...

Keyword(s):

Colorectal Cancer ◽

Lynch Syndrome ◽

Cumulative Risk ◽

Germline Mutations ◽

Han Chinese ◽

Chinese Patients ◽

Mutation Carriers ◽

Amsterdam Criteria ◽

Cumulative Risks ◽

Age And Sex

AbstractPatients with Lynch syndrome have a high risk of colorectal cancer (CRC). In this study, we estimated the age- and sex-specific cumulative risks of CRC in Han Chinese patients with Lynch syndrome caused by the pathogenic germline mutations in MLH1 or MSH2 in Taiwan. Based on 321 mutation carriers and 419 non-mutation carriers from 75 pedigrees collected in an Amsterdam criteria family registry in Taiwan, the age- and sex-specific cumulative risks of CRC in male carriers of mutation in MLH1 and MSH2 at the age of 70 years were 60.3% (95% confidence interval (CI) = 31.1%–89.9%) and 76.7% (95% CI = 37.2%–99.0%), respectively. For females, the cumulative risks of CRC at the age of 70 were estimated to be 30.6% (95% CI = 14.3%–57.7%) and 49.3% (95% CI = 21.9%–84.5%) in the carriers of MLH1 and MSH2 germline mutations, respectively. In conclusion, the cumulative risks of CRC at the age of 70 in the Han Chinese patients is higher in mutation carriers than non-mutation carriers and male mutation carriers have a higher cumulative risk of developing CRC than the female mutation carriers.

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Results of clot waveform analysis and thrombin generation test for a plasma-derived factor VIIa and X mixture (MC710) in haemophilia patients with inhibitors-phase I trial: 2nd report

Haemophilia ◽

10.1111/hae.12024 ◽

2012 ◽

Vol 19 (2) ◽

pp. 330-337 ◽

Cited By ~ 14

Author(s):

A. Shirahata ◽

K. Fukutake ◽

J. Mimaya ◽

J. Takamatsu ◽

M. Shima ◽

...

Keyword(s):

Phase I ◽

Thrombin Generation ◽

Phase I Trial ◽

Factor Viia ◽

Waveform Analysis ◽

Generation Test

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Plasma fibrin clot properties in the G20210A prothrombin mutation carriers following venous thromboembolism: the effect of rivaroxaban

Thrombosis and Haemostasis ◽

10.1160/th17-01-0060 ◽

2017 ◽

Vol 117 (09) ◽

pp. 1739-1749 ◽

Cited By ~ 8

Author(s):

Agnieszka Janion-Sadowska ◽

Joanna Natorska ◽

Jakub Siudut ◽

Michal Zabczyk ◽

Andrzej Stanisz ◽

...

Keyword(s):

Venous Thromboembolism ◽

Fibrin Clot ◽

Clot Lysis ◽

Mutation Carriers ◽

Lysis Time ◽

Prothrombin Mutation ◽

Fibrinolysis Inhibitor ◽

Heterozygous Carriers ◽

Mutation Group ◽

Clot Structure

SummaryWe sought to investigate whether the G20210A prothrombin mutation modifies plasma fibrin clot properties in patients after venous thromboembolism (VTE) and how rivaroxaban treatment affects these alterations. We studied 34 prothrombin mutation heterozygous carriers and sex- and age-matched 34 non-carriers, all at least three months since the first VTE episode, before and during treatment with rivaroxaban. Clot permeability (Ks) and clot lysis time (CLT) with or without elimination of thrombin activatable fibrinolysis inhibitor (TAFI) were assessed at baseline, 2–6 hours (h) after and 20–25 h after intake of rivaroxaban (20 mg/day). At baseline, the prothrombin mutation group formed denser clots (Ks −12 %, p=0.0006) and had impaired fibrinolysis (CLT +14 %, p=0.004, and CLT-TAFI +13 %, p=0.03) compared with the no mutation group and were similar to those observed in 15 healthy unrelated prothrombin mutation carriers. The G20210A prothrombin mutation was the independent predictor for Ks and CLT before rivaroxaban intake. At 2–6 h after rivaroxaban intake, clot properties improved in both G20210A carriers and non-carriers (Ks +38 %, and +37 %, CLT −25 % and −25 %, CLT-TAFI −20 % and −24 %, respectively, all p<0.001), but those parameters were worse in the prothrombin mutation group (Ks −12.8 %, CLT +17 %, CLT-TAFI +13 %, all p<0.001). Rivaroxaban concentration correlated with fibrin clot properties. After 20–25 h since rivaroxaban intake most clot properties returned to baseline. Rivaroxaban-related differences in clot structure were confirmed by scanning electron microscopy images. In conclusion, rivaroxaban treatment, though improves fibrin clot properties, cannot abolish more prothrombotic fibrin clot phenotype observed in prothrombin mutation carriers following VTE.

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