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Even though the combined use of ultrasound (US) and alpha-fetoprotein (AFP) is recommended for the surveillance of hepatocellular carcinoma (HCC), the utilization of AFP has its challenges, including accuracy dependent on its cut-off levels, degree of liver necroinflammation, and etiology of liver disease. Though various studies have demonstrated the utility of protein induced by vitamin K absence II (PIVKA-II) in surveillance, treatment monitoring, and predicting recurrence, it is still not recommended as a routine biomarker test. A panel of 17 experts from Asia-Pacific, gathered to discuss and reach a consensus on the clinical usefulness and value of PIVKA-II for the surveillance and treatment monitoring of HCC, based on six predetermined statements. The experts agreed that PIVKA-II was valuable in the detection of HCC in AFP-negative patients, and could potentially benefit detection of early HCC in combination with AFP. PIVKA-II is clinically useful for monitoring curative and intra-arterial locoregional treatments, outcomes, and recurrence, and could potentially predict microvascular invasion risk and facilitate patient selection for liver transplant. However, combining PIVKA-II with US and AFP for HCC surveillance, including small HCC, still requires more evidence, whilst its role in detecting AFP-negative HCC will potentially increase as more patients are treated for hepatitis-related HCC. PIVKA-II in combination with AFP and US has a clinical role in the Asia-Pacific region for surveillance. However, implementation of PIVKA-II in the region will have some challenges, such as requiring standardization of cut-off values, its cost-effectiveness and improving awareness among healthcare providers.

The new oral anticoagulants have many advantages over warfarin, but one disadvantage is the inability to rapidly reverse their anticoagulant effects. Andexanet, a small-molecule factor Xa fragment, rapidly lowered levels of rivaroxaban and apixaban in older healthy volunteers. The direct factor Xa inhibitors apixaban, rivaroxaban, and edoxaban are used in the prevention and treatment of thromboembolism. Indications for the use of these agents include the prevention of stroke in patients with nonvalvular atrial fibrillation, the treatment and secondary prevention of deep-vein thrombosis and pulmonary embolism, and the prevention of venous thrombosis after orthopedic surgery. In spite of the demonstrated safety and efficacy of factor Xa inhibitors, as well as their practical advantages over vitamin K antagonists such as warfarin, the lack of a specific antidote to reverse their anticoagulant effects is an important limitation. In clinical trials involving . . .

The inactivation of thrombin by antithrombin is highly enhanced by the presence of heparin chains forming “bridges” between the two proteins. X-ray structures for such ternary complexes have been published, but the molecular background of the lower efficiency of smaller heparinoids on thrombin inhibition remains poorly understood. Antithrombin-resistant prothrombin mutants (mutations affecting Arg596 in prothrombin) have been reported that cause severe thrombophilia. Our aim was to study the interactions in the antithrombin–thrombin Michaelis complex both in the presence and the absence of a heparinoid chain and in the presence of pentasaccharide by using molecular dynamics. We also intended to study the complexes of thrombin mutants as well as a known alternative antithrombin conformation at the “hinge” region built using docking. The binding between the proteins was investigated by Gaussian Accelerated Molecular Dynamics (GaMD). We compared the contribution of several amino acids at the binding “exosites” between AT and the wild type and mutant thrombins and between systems containing or not containing a heparinoid. In the docking-based simulations, several of the analyzed amino acid pairs no longer contributed to the interaction, suggesting that the open “hinge” conformation has limited biological relevance. We could identify multiple conformational types using clustering, revealing high flexibility in mutants and systems without heparinoid, probably indicating lower stability. We were also able to detect the allosteric effects of the ligands on the bound thrombin. In summary, we were able to obtain conformations using GaMD that can explain the better protein–protein interactions in the ternary complexes and the impaired AT binding of the thrombin Arg596 mutants at an atomic level.

The aim of this retrospective study was to compare andexanet alfa and 4-factor prothrombin complex (4F-PCC) for reversal of factor Xa (FXa)-inhibitor bleeding. Patients that received andexanet alfa for reversal were included. An equivalent number of patients administered 4F-PCC for FXa-inhibitor bleeding were randomly selected as historical controls. The primary outcome was effective hemostasis achievement within 12 h, defined using ANNEXA-4 criteria. Thromboembolic events and mortality within 30 days were also evaluated. A total of 32 patients were included. Baseline characteristics were not statistically different between andexanet alfa (n = 16) and 4F-PCC (n = 16). Intracranial bleeding was the primary reversal indication in 43.8% versus 62.5% of patients, respectively. Effective hemostasis was reached in 75.0% of andexanet alfa patients compared to 62.5% of 4F-PCC patients (P = .70). Thromboembolic events occurred in 4 (25.0%) patients and 3 (18.8%) patients, respectively (P = .99). Mortality incidence was 12.5% and 31.3%, respectively (P = .39). Andexanet alfa and 4F-PCC attained hemostasis in a majority of patients. A high, but a similar rate of thromboembolic events was seen with both treatments. Prospective studies are needed to elucidate comparative risks and benefits of the 2 agents.

This retrospective observational analysis was conducted to explore the correlation between the frequency of bleeding in digestive system tumors and various coagulation indexes, providing clinical data for predicting multiple bleeding episodes in patients. A retrospective collection was made of 41 patients with digestive system tumors who presented with gastrointestinal bleeding in our hospital from 2020 to 2024. The number of bleeding episodes ranged from 1 to 5. At the same time, the coagulation indexes at the time of admission were collected. The SPSS statistical software was used to analyze the correlation between the number of bleeding episodes and the coagulation indexes. A positive correlation was found between the number of bleeding episodes and the percentage activity of prothrombin (Pearson r  = 0.199, p  = 0.034), while there was no significant correlation with other coagulation indexes (prothrombin time, international normalized ratio, partial thromboplastin time, thrombin time, fibrinogen, and D - dimer). Also, no significant correlation was found between the number of bleeding episodes and other clinicopathological characteristics of the patients. The continuous increase in the elevated percentage activity of prothrombin may be associated with predicting re-bleeding in patients with digestive tract tumors.

Thrombophilias are usually caused by loss-of-function mutations in natural anticoagulants or gain-of-function mutations in procoagulants. A mutation in a Japanese family documents a novel mechanism, procoagulant (prothrombin) resistance to anticoagulant (antithrombin). Patients with hereditary thrombophilia often present with unusual clinical episodes of venous thrombosis at a young age and recurrence in atypical vessels, often with a family history of the condition. 1 Genetic studies of hereditary thrombophilia have revealed two types of genetic defects: loss-of-function mutations in the natural anticoagulants antithrombin, protein C, and protein S, along with gain-of-function mutations in procoagulant factors V (factor V Leiden) and II (prothrombin G20210A). 2 To date, numerous genetic defects have been found in families with hereditary thrombophilia, but there may be many undiscovered causative mutations. 3 Here, we describe a case of hereditary thrombosis induced by . . .

In a randomized trial involving patients who were hypotensive after trauma, 30-day mortality was 33% among patients who received standard crystalloid-based resuscitation as compared with 23% among patients who received fresh frozen plasma in addition to standard measures.

Our objective was to maintain low interlaboratory variation and bias in international normalized ratio (INR) results following a network change in instrumentation and reagents, using a process of ongoing standardization and harmonization. Network-wide standardization to new common instrument and reagent platforms followed by network-wide application of a simple novel process of verification of international sensitive index and mean normal prothrombin time values for each new lot of prothrombin time (PT) reagent that does not require use of World Health Organization reference thromboplastin or INR calibration/certified plasma. The network transitioned from mechanical hemostasis detection instruments with associated PT reagent (Diagnostica Stago; NeoPTimal) to optical detection (ACL TOPs) with associated PT reagent (Werfen; RecombiPlasTin 2G). Comparing 3 years of data for each situation, the network (n = 27 laboratories) maintained low INR variability and bias relative to general mechanical and optical groups and other laboratories. Harmonized support for patient management of vitamin K antagonists such as warfarin was continuously maintained in our geography, with potentially positive implications for other coagulation laboratories and geographies. For the United States in particular, paucity of US Food and Drug Administration-cleared INR certified plasmas potentially compromises INR test accuracy; our novel approach may provide workable alternatives for other laboratories/networks.

In a previous study, we reported that human endothelial cells (ECs) express and produce their own coagulation factors (F) that can activate cell surface FX without the additions of external proteins or phospholipids. We now describe experiments that detail the expression and production in ECs and fibroblasts of the clotting proteins necessary for formation of active prothrombinase (FV–FX) complexes to produce thrombin on EC and fibroblast surfaces. EC and fibroblast thrombin generation was identified by measuring: thrombin activity; thrombin–antithrombin complexes; and the prothrombin fragment 1.2 (PF1.2), which is produced by the prothrombinase cleavage of prothrombin (FII) to thrombin. In ECs, the prothrombinase complex uses surface-attached FV and γ-carboxyl-glutamate residues of FX and FII to attach to EC surfaces. FV is also on fibroblast surfaces; however, lower fibroblast expression of the gene for γ-glutamyl carboxylase ( GGCX ) results in production of vitamin K-dependent coagulation proteins (FII and FX) with reduced surface binding. This is evident by the minimal surface binding of PF1.2, following FII activation, of fibroblasts compared to ECs. We conclude that human ECs and fibroblasts both generate thrombin without exogenous addition of coagulation proteins or phospholipids. The two cell types assemble distinct forms of prothrombinase to generate thrombin.