Human platelet concentrates treated with microbicidal 405 nm light retain hemostasis activity

Chemical and UV light-based pathogen reduction technologies are currently in use for human platelet concentrates (PCs) to enhance safety from transfusion-transmitted infections. Relative to UV light, 405 nm violet-blue light in the visible spectrum is known to be less harmful. Hence, in this report for the first time, we have assessed the global hemostasis activity of PCs stored in plasma and the activities of six plasma coagulation factors (CFs) as a measure of in vitro hemostatic activity following exposure to the microbicidal 405 nm light. Apheresis PC samples collected from each screened human donor (n = 22) were used for testing of PCs and platelet poor plasma (PPP). Both PCs and PPPs were treated for 5 h with 405 nm light to achieve a previously established microbicidal light dose of 270 J/cm2. Activated partial thromboplastin time and prothrombin time-based potency assays using a coagulation analyzer and hemostatic capacity via Thromboelastography were analyzed. Thromboelastography analysis of the light-treated PCs and plasma present in the PCs showed little difference between the treated and untreated samples. Further, plasma present in the PCs during the light treatment demonstrated a better stability in potency assays for several coagulation factors compared to the plasma alone prepared from PCs first and subjected to the light treatment separately. Overall, PCs stored in plasma treated with 405 nm violet-blue light retain activity for hemostasis.

Age-related variation in coagulation factors in non-valvular atrial fibrillation patients receiving direct oral anticoagulants

Age is a significant risk factor for ischemic stroke. However, the influence of aging on coagulation parameters in non-valvular atrial fibrillation (NVAF) patients treated with direct oral anticoagulants (DOACs) remains unclear. A total of 775 samples were collected from 224 NVAF patients receiving apixaban, edoxaban or rivaroxaban. The samples were categorized into three age groups: (i) ≤ 64 years, (ii) 65-74 years, and (iii) ≥ 75 years (apixaban: N = 48, 108, 119; edoxaban: N = 63, 68, 126; rivaroxaban: N = 115, 90, 38, respectively). Coagulation parameters including fibrinogen (Fbg), factor II, factor V, factor VII, factor X, and D-dimer, were compared between the three age groups for each drug. The slopes in the correlation between drug concentrations and modified diluted prothrombin time (mdPT) were also assessed. Fbg and factor V increased with age, while factor II and factor X decreased. Factor VII and D-dimer showed no significant differences across age categories. The slope in response to drug concentrations was similar between the age groups. In NVAF patients treated with apixaban, edoxaban and rivaroxaban, some coagulation parameters exhibited age-related variation. However, the response of mdPT to drug concentration was consistent across age categories.

ATR1 A1166C (rs5186), FII G20210A (rs1799963), FV G1691A (rs6025), FXIII 97G > T (rs11466016) and MTHFR A1298C (rs1801131) polymorphisms and the risk of ST-elevation myocardial infarction in young Mexican individuals

BACKGROUND

Previous studies had identified genetic variants associated with Myocardial Infarction, but results are inconclusive. We examined the association between FII G20210A (rs1799963), FV G1691A (rs6025), FXIII 97G > T (rs11466016), ATR1 A1166C (rs5186) and MTHFR A1298C (rs1801131) polymorphisms and ST elevation Myocardial Infarction in young Mexican individuals.

METHODS

We included a total of 350 patients with Myocardial Infarction <45 years old and 350 controls matched by age and gender. The polymorphisms were analyzed by PCR-RFLP using specific restriction enzymes. DNA fragments were separated by electrophoresis in 2% gel of agarose and visualized using SYBR green.

RESULTS

The A1166C (p = 0.004) but not FXIII 97G > T (p = 0.19), G20210A (p = 0.32), G1691A (p = No significant) and A1298C (p = 0.21) polymorphisms were associated with increased risk for ST elevation Myocardial Infarction. Moreover, dyslipidemia, hypertension, smoking and family history of atherothrombotic disease were associated.

CONCLUSIONS

We found that A1166C represented increased risk for ST elevation Myocardial Infarction. However, G20210A, G1691A, 97G > T, and A1298C were not associated. In addition, we had determined that Glu298Asp, PLA1/A2, TAFI Thr325Ile, ACE I/D, AGT M235T and PAI-1 4G/5G polymorphisms represented increased risk in the same group of patients. However, MTHFR C677T, AGT T174M, FV G1691A, TSP-1 N700S, MTHFR C677T and TAFI 174 M polymorphisms were no associated. Our results suggest that in young patients with ST Myocardial Infarction, those polymorphisms could contribute to premature endothelial dysfunction, atherothrombosis, vasoconstriction, increased platelet aggregation, muscle cell migration and proliferation. Further studies are required to try to better assess gene-gene and gene-modifiable factors interaction.

Effect of cardiopulmonary bypass on coagulation factors II, VII and X in a primate model: an exploratory pilot study

OBJECTIVES

The use of cardiopulmonary bypass (CPB) in cardiac surgery is a major risk factor for postoperative bleeding. We hypothesized that consumptive coagulopathy and haemodilution influence the coagulation factors; therefore, we aimed to estimate the activity profiles of coagulation factors II, VII and X during CPB circulation.

METHODS

A 120-min bypass was surgically established in cynomolgus monkeys (n = 7). Activities of coagulation factors II, VII and X were measured at 6 time points during the experiment (baseline, 0, 30, 60, 120 min of bypass and 60 min after bypass). To assess the influence of consumptive coagulopathy, the values were adjusted for haemodilution using the haematocrit values. Data were expressed as mean (standard deviation).

RESULTS

Activities of coagulation factors decreased during the experiment. In particular, the activities for II, VII and X were decreased the most by 44.2% (5.0), 61.4% (4.3) and 49.0% (3.7) at 30 min following CPB initiation (P < 0.001, P < 0.001 and P < 0.001, respectively). Following adjustments for haemodilution, change magnitudes lessened but remained significant for factor VII. The adjusted concentration of factor VII was observed to decrease from the baseline to the initiation of bypass circulation.

CONCLUSIONS

In conclusion, coagulation factor II, VII and X concentrations decreased during CPB. Following adjustment for haemodilution, a decrease in concentration was observed with factor VII.

Anticoagulants in adult extracorporeal membrane oxygenation: alternatives to standardized anticoagulation with unfractionated heparin

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a vital technique for severe respiratory or heart failure patients. Bleeding and thrombotic events are common during ECMO and negatively impact patient outcomes. Unfractionated heparin is the primary anticoagulant, but its adverse effects limit its use, necessitating alternative anticoagulants.

OBJECTIVE

Review available alternative anticoagulants for adult ECMO patients. Explore potential novel anticoagulants for future ECMO use. Aim to reduce complications (bleeding and thrombosis) and improve safety and efficacy for critically ill ECMO patients.

METHODS

Comprehensive literature review of existing and emerging anticoagulants for ECMO.

RESULTS

Identified a range of alternative anticoagulants beyond unfractionated heparin. Evaluated their potential utility in mitigating ECMO-related complications.

CONCLUSION

Diverse anticoagulant options are available and under investigation for ECMO. These alternatives may enhance patient safety and outcomes during ECMO support. Further research and clinical studies are warranted to determine their effectiveness and safety profiles.

Irregularities of Coagulation in Hypertension

PURPOSE OF REVIEW

This review article summarizes the role of coagulation in the pathogenesis of hypertension. It specifically focuses on significant factors and markers associated with coagulation, including D-dimer, fibrinogen and fibrin, prothrombin, P-selectin, soluble urokinase plasminogen activator receptor, thrombomodulin, tissue factor, tissue plasminogen activator, von Willebrand factor, β-thromboglobulin, and Stuart-Prower factor.

RECENT FINDINGS

D-dimer levels were elevated in hypertensive individuals compared to healthy controls, and the levels increased with the severity of hypertension. These findings indicate that increased coagulation activity of fibrin plays a role in the development of thromboembolic complications in hypertensive patients. Additionally, both fibrinogen levels and D-dimer levels displayed a positive correlation with the duration of hypertension, suggesting that these biomarkers were positively associated with the length of time an individual had been hypertensive. Increased systolic and diastolic blood pressures have been linked to higher levels of prothrombin time and activated partial thromboplastin time in individuals with hypertension as well as those with normal blood pressure. Also, the presence of P-selectin, produced by activated platelets and endothelial cells during angiotensin II stimulation, played a role in the development of cardiac inflammation and fibrosis associated with hypertension. Moreover, the change in systolic blood pressure was associated with baseline soluble urokinase plasminogen activator receptor (suPAR) in hypertensive participants, and the change in suPAR levels was associated with the development of hypertension. Moreover, it was observed a decrease in thrombomodulin expression in the placenta of preeclamptic patients, suggesting its potential involvement in placental dysfunction, possibly driven by an imbalance in angiogenic factors. Tissue factors and autophagy might have significant implications in the pathogenesis of chronic thromboembolic pulmonary hypertension, particularly in the context of vascular remodelling. Likewise, ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) might be a promising biomarker for the early detection of pulmonary arterial hypertension and the von Willebrand factor is a candidate prognostic biomarker. The arterial β-thromboglobulin levels were significantly lower than venous levels. This article concludes that D-dimer, fibrinogen and fibrin, prothrombin, P-selectin, soluble urokinase plasminogen activator receptor, thrombomodulin, tissue factor, tissue plasminogen activator, von Willebrand factor, and β-thromboglobulin are important factors involved in the pathogenesis of hypertension.

The international normalised ratio to monitor coagulation factor production during normothermic machine perfusion of human donor livers

BACKGROUND

Normothermic machine perfusion (NMP) of donor livers allows for new diagnostic and therapeutic strategies. As the liver produces most of the haemostatic proteins, coagulation assays such as the International Normalised Ratio (INR) performed in perfusate may be useful to assess hepatocellular function of donor livers undergoing NMP. However, high concentrations of heparin and low levels of fibrinogen may affect coagulation assays.

METHODS

Thirty donor livers that underwent NMP were retrospectively included in this study, of which 18 were subsequently transplanted. We measured INRs in perfusate in presence or absence of exogenously added fibrinogen and/or polybrene. Additionally, we prospectively included 14 donor livers that underwent NMP (of which 11 were transplanted) and measured INR using both a laboratory coagulation analyser and a point-of-care device.

RESULTS

In untreated perfusate samples, the INR was above the detection limit in all donor livers. Addition of both fibrinogen and polybrene was required for adequate INR assessment. INRs decreased over time and detectable perfusate INR values were found in 17/18 donor livers at the end of NMP. INR results were similar between the coagulation analyser and the point-of-care device, but did not correlate with established hepatocellular viability criteria.

CONCLUSIONS

Most of the donor livers that were transplanted showed a detectable perfusate INR at the end of NMP, but samples require processing to allow for INR measurements using laboratory coagulation analysers. Point-of-care devices bypass this need for processing. The INR does not correlate with established viability criteria and might therefore have additional predictive value.

Coagulation biomarkers and coronavirus disease 2019 phenotyping: a prospective cohort study

BACKGROUND

Because severe acute respiratory syndrome coronarivus 2 (SARS-CoV-2) leads to severe conditions and thrombus formation, evaluation of the coagulation markers is important in determining the prognosis and phenotyping of patients with COVID-19.

METHODS

In a prospective study that included 213 COVID-19 patients admitted to the intensive care unit (ICU) the levels of antithrombin, C-reactive protein (CRP); factors XI, XII, XIII; prothrombin and D-dimer were measured. Spearman's correlation coefficient was used to assess the pairwise correlations between the biomarkers. Hierarchical and non-hierarchical cluster analysis was performed using the levels of biomarkers to identify patients´ phenotypes. Multivariate binary regression was used to determine the association of the patient´s outcome with clinical variables and biomarker levels.

RESULTS

The levels of factors XI and XIII were significantly higher in patients with less severe COVID-19, while factor XIII and antithrombin levels were significantly associated with mortality. These coagulation biomarkers were associated with the in-hospital survival of COVID-19 patients over and above the core clinical factors on admission. Hierarchical cluster analysis showed a cluster between factor XIII and antithrombin, and this hierarchical cluster was extended to CRP in the next step. Furthermore, a non-hierarchical K-means cluster analysis was performed, and two phenotypes were identified based on the CRP and antithrombin levels independently of clinical variables and were associated with mortality.

CONCLUSION

Coagulation biomarkers were associated with in-hospital survival of COVID-19 patients. Lower levels of factors XI, XII and XIII and prothrombin were associated with disease severity, while higher levels of both CRP and antithrombin clustered with worse prognosis. These results suggest the role of coagulation abnormalities in the development of COVID-19 and open the perspective of identifying subgroups of patients who would benefit more from interventions focused on regulating coagulation.

Interpenetrating network expansion sponge based on chitosan and plasma for ultrafast hemostasis of arterial bleeding wounds

Preventing arterial hemorrhage by intervening within the first few minutes is critical to the patient's life. Hemostatic materials have been developed over the last decades to address this issue, nevertheless these materials alone do not contribute to improve the survival effects in many extreme conditions, which is usually caused by penetrating arterial bleeding wounds that are incompressible and deep arterial bleeding with irregularly shapes. It is well known that, after calcium ion stimulation, many intriguing changes occurred in the major components of plasma, including the activation of several coagulation factors, such as the conversion of fibrinogen to fibrin, prothrombin to thrombin, and so on. Therefore, we constructed an expansion sponge with interpenetrating network based on chitosan and plasma, while various activated coagulation factors in plasma were also loaded into the pore structure of chitosan sponges. The prepared CS-PG sponge is capable of providing a simpler and more efficient method for treating high-pressure arterial bleeding wounds, which includes three steps: Rapid sealing and adhension, Thrombin catalysis and Activated autocoagulation. As the next generation bioactive materials, compared to conventional hemostatic materials, CS-PG sponge demonstrated superior hemostatic characteristics in both rabbit femoral artery damage and rat liver injury models.

Atrial inflammation and microvascular thrombogenicity are increased in deceased COVID-19 patients

BACKGROUND

Histopathological studies have shown inflammation, cardiomyocyte injury, and microvascular thrombosis in the ventricular myocardium of patients with coronavirus disease 2019 (COVID-19). However, although atrial dysfunction is common in COVID-19, little is known about histopathological changes in the atria of the heart. We therefore analyzed inflammation, cardiomyocyte injury, and microvascular thrombogenicity in the atria of deceased patients with COVID-19.

METHODS

Atrial tissue was obtained from autopsied COVID-19 (n=16) patients and control patients (n=10) and analyzed using immunohistochemistry. The infiltration of CD45+ leukocytes, CD3+ T lymphocytes, CD68+ macrophages, MPO+ neutrophils, and Tryptase+ mast cells were quantified as well as cardiomyocyte damage and microvascular thrombosis. In addition, Tissue Factor (TF) and Factor XII (FXII) were quantified as markers of microvascular thrombogenicity.

RESULTS

The numbers of lymphocytes, macrophages, and neutrophils were significantly increased in the atrial myocardium and epicardial atrial adipose tissue of COVID-19 patients compared with the control group. This was accompanied by dispersed cardiomyocyte injury, the occasional presence of microvascular thrombosis, and an increased presence of TF and FXII in the microvascular endothelium.

CONCLUSIONS

Severe COVID-19 induces inflammation, cardiomyocyte injury, and microvascular thrombosis in the atria of the heart.

Mechanism of VKORC1 and VKORC1L1 signaling in the effects of sodium dehydroacetate on coagulation factors in rat hepatocytes

Sodium dehydroacetate (Na-DHA) is widely used as an antibacterial and preservative additive in food and cosmetics. Previously, we reported that repeated oral administration of Na-DHA induces coagulation disorders, and inhibited liver vitamin K epoxide reductase complex subunit 1 (VKORC1) and VKORC1-like protein 1 (VKORC1L1) in rats. However, the effects of Na-DHA on coagulation factors in rat hepatocytes and the mechanism of VKORC1 and VKORC1L1 signaling in that process are unclear. Here, we constructed stable Vkorc1 and Vkorc1l1 overexpressing cell lines using lentiviruses and transfected small interfering RNAs into buffalo rat liver BRL3A cells for Vkorc1 and Vkorc1l1 overexpression and silencing, respectively. After treatment with 5 mmol/L Na-DHA for 24 h, VKORC1 and VKORC1L1 expression levels were detected by real-time PCR and western blotting. Vitamin K (VK) and factor IX (FIX) contents were detected using enzyme linked immunosorbent assays. We observed that Na-DHA inhibited VKORC1 and VKORC1L1 expression levels and reduced VK and FIX levels in rat hepatocytes. Overexpression or silencing of Vkorc1 and Vkorc1l1 increased or decreased, respectively, the production and secretion of VK and FIX in rat hepatocytes, and alleviated or aggravated the inhibitory effects of Na-DHA on VKORC1 and VKORC1L1 expression levels. Taken together, the results indicated that both VKORC1 and VKORC1L1 signaling play regulatory roles in the effects of Na-DHA on coagulation factors in rat hepatocytes.

DNA methylation changes and increased mRNA expression of coagulation proteins, factor V and thrombomodulin in Fuchs endothelial corneal dystrophy

Late-onset Fuchs endothelial corneal dystrophy (FECD) is a disease affecting the corneal endothelium (CE), associated with a cytosine-thymine-guanine repeat expansion at the CTG18.1 locus in the transcription factor 4 (TCF4) gene. It is unknown whether CTG18.1 expansions affect global methylation including TCF4 gene in CE or whether global CE methylation changes at advanced age. Using genome-wide DNA methylation array, we investigated methylation in CE from FECD patients with CTG18.1 expansions and studied the methylation in healthy CE at different ages. The most revealing DNA methylation findings were analyzed by gene expression and protein analysis. 3488 CpGs had significantly altered methylation pattern in FECD though no substantial changes were found in TCF4. The most hypermethylated site was in a predicted promoter of aquaporin 1 (AQP1) gene, and the most hypomethylated site was in a predicted promoter of coagulation factor V (F5 for gene, FV for protein). In FECD, AQP1 mRNA expression was variable, while F5 gene expression showed a ~ 23-fold increase. FV protein was present in both healthy and affected CE. Further gene expression analysis of coagulation factors interacting with FV revealed a ~ 34-fold increase of thrombomodulin (THBD). THBD protein was detected only in CE from FECD patients. Additionally, we observed an age-dependent hypomethylation in elderly healthy CE.Thus, tissue-specific genome-wide and gene-specific methylation changes associated with altered gene expression were discovered in FECD. TCF4 pathological methylation in FECD because of CTG18.1 expansion was ruled out.

Dexmedetomidine induced hypotension and hemostatic markers

Background and Aims

The hemostatic system undergoes extensive alterations following surgical trauma leading to a hypercoagulable state. We assessed and compared the changes in platelet aggregation, coagulation, and fibrinolysis status during normotensive and dexmedetomidine-induced hypotensive anesthesia in patients undergoing spine surgery.

Material and Methods

Sixty patients undergoing spine surgery were randomly allocated into two groups: normotensive and dexmedetomidine-induced hypotensive groups. Platelet aggregation was assessed preoperatively, 15 min after induction, 60 min, and 120 min after skin incision, at the end of surgery, 2 h and 24 h postoperatively. Prothrombin time (PT), activated partial thromboplastin time (aPTT), platelet count, antithrombin III, fibrinogen, and D-dimer levels were measured preoperatively, 2 h and 24 h postoperatively.

Results

Preoperative platelet aggregation (%) was comparable between both groups. Platelet aggregation significantly increased intraoperative at 120 min after skin incision and postoperatively in the normotensive group compared to the preoperative value (P < 0.05) but it was insignificantly decreased during the intraoperative induced hypotensive period in the dexmedetomidine-induced hypotensive group (P > 0.05). Postoperative PT, aPTT significantly increased and platelet count, and antithrombin III significantly decreased in the normotensive group compared to the preoperative value (P < 0.05) but they were not significantly changed in the hypotensive group (P > 0.05). Postoperative D-dimer significantly increased in the two groups compared to the preoperative value (P < 0.05).

Conclusion

Intraoperative and postoperative platelet aggregation significantly increased in the normotensive group with significant alterations of the coagulation markers. Dexmedetomidine-induced hypotensive anesthesia prevented the increased platelet aggregation that occurred in the normotensive group with better preservation of platelet and coagulation factors.

Changes in Coagulation Study and Risk of Developing Cholesteatoma: Is There a Link?

BACKGROUND AND OBJECTIVES

The etiopathogenesis of acquired pediatric cholesteatoma has not yet been fully clarified. Recent studies and modern technologies have led researchers to look for explanations at a molecular level. This study aims to understand if the origins of cholesteatoma could be related to dysfunctions in coagulation factors, thereby emphasizing its role in angiogenesis. Subjects and.

METHODS

This was a retrospective case-control study carried out at a tertiary hospital center between January 2010 and December 2020. The study included 92 children. The variables of the summary coagulation study (partial thromboplastin time, prothrombin time, and international normalized ratio) were compared among children with and without development of chronic otitis media with cholesteatoma.

RESULTS

The cases and controls were comparable in terms of age, type, and number of times that ventilation tubes were placed. Partial thromboplastin times tended to be higher in children who developed cholesteatoma, with a statistically significant difference between the two groups in terms of normal and abnormal partial thromboplastin times (p=0.029).

CONCLUSIONS

The results of this case control study indicate that slight extension of partial thromboplastin times in the coagulation study may not meet the criteria for diagnosis of certain hematological pathologies or clinical significance, but at a molecular level may already have implications for activation of angiogenesis and other growth factors involved in the onset, growth, and expansion of acquired pediatric cholesteatoma.

Discovery of anti-stroke active substances in Guhong injection based on multi-phenotypic screening of zebrafish

Ischemic stroke is a leading cause of death worldwide, and it remains an urgent task to develop novel and alternative therapeutic strategies for the disease. We previously reported the positive effects of Guhong injection (GHI), composed of safflower extract and aceglutamide, in promoting functional recovery in ischemic stroke mice. However, the active substances and pharmacological mechanism of GHI is still elusive. Aiming to identify the active anti-stroke components in GHI, here we conducted a multi-phenotypic screening in zebrafish models of phenylhydrazine-induced thrombosis and ponatinib-induced cerebral ischemia. Peripheral and cerebral blood flow was quantified endogenously in erythrocytes fluorescence-labeled thrombosis fish, and baicalein and rutin were identified as major anti-thrombotic substances in GHI. Moreover, using a high-throughput video-tracking system, the effects of locomotion promotion of GHI and its main compounds were analyzed in cerebral ischemia model. Chlorogenic acid and gallic acid showed significant effects in preventing locomotor dyfunctions. Finally, GHI treatment greatly decreased the expression levels of coagulation factors F7 and F2, NF-κB and its mediated proinflammatory cytokines in the fish models. Molecular docking suggested strong affinities between baicalein and F7, and between active substances (baicalein, chlorogenic acid, gallic acid, and rutin) and NF-κB p65. In summary, our findings established a novel drug discovery method based on multi-phenotypic screening of zebrafish, provided endogenous evidences of GHI in preventing thrombus formation and promoting behavioral recovery after cerebral ischemia, and identified baicalein, rutin, chlorogenic acid, and gallic acid as active compounds in the management of ischemic stroke.

Relationships between coagulation factors and thrombin generation in a general population with arterial and venous disease background

Background

The current study aims to identify the relationships between coagulation factors and plasma thrombin generation in a large population-based study by comparing individuals with a history of arterial or venous thrombosis to cardiovascular healthy individuals.

Methods

This study comprised 502 individuals with a history of arterial disease, 195 with history of venous thrombosis and 1402 cardiovascular healthy individuals (reference group) from the population-based Gutenberg Health Study (GHS). Calibrated Automated Thrombography was assessed and coagulation factors were measured by means of BCS XP Systems. To assess the biochemical determinants of TG variables, a multiple linear regression analysis, adjusted for age, sex and antithrombotic therapy, was conducted.

Results

The lag time, the time to form the first thrombin, was mainly positively associated with the natural coagulant and anti-coagulant factors in the reference group, i.e. higher factors result in a longer lag time. The same determinants were negative for individuals with a history of arterial or venous thrombosis, with a 10 times higher effect size. Endogenous thrombin potential, or area under the curve, was predominantly positively determined by factor II, VIII, X and IX in all groups. However, the effect sizes of the reported associations were 4 times higher for the arterial and venous disease groups in comparison to the reference group.

Conclusion

This large-scale analysis demonstrated a stronger effect of the coagulant and natural anti-coagulant factors on the thrombin potential in individuals with a history of arterial or venous thrombosis as compared to healthy individuals, which implicates sustained alterations in the plasma coagulome in subjects with a history of thrombotic vascular disease, despite intake of antithrombotic therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00392-0.

Role of LL-37 in thrombotic complications in patients with COVID-19

Blood clot formation induced by dysfunctional coagulation is a frequent complication of coronavirus disease 2019 (COVID-19) and a high-risk factor for severe illness and death. Neutrophil extracellular traps (NETs) are implicated in COVID-19-induced immunothrombosis. Furthermore, human cathelicidin, a NET component, can perturb the interaction between the SARS-CoV-2 spike protein and its ACE2 receptor, which mediates viral entry into cells. At present, however, the levels of cathelicidin antimicrobial peptides after SARS-CoV-2 infection and their role in COVID-19 thrombosis formation remain unclear. In the current study, we analyzed coagulation function and found a decrease in thrombin time but an increase in fibrinogen level, prothrombin time, and activated partial thromboplastin time in COVID-19 patients. In addition, the cathelicidin antimicrobial peptide LL-37 was upregulated by the spike protein and significantly elevated in the plasma of patients. Furthermore, LL-37 levels were negatively correlated with thrombin time but positively correlated with fibrinogen level. In addition to platelet activation, cathelicidin peptides enhanced the activity of coagulation factors, such as factor Xa (FXa) and thrombin, which may induce hypercoagulation in diseases with high cathelicidin peptide levels. Injection of cathelicidin peptides promoted the formation of thrombosis, whereas deletion of cathelicidin inhibited thrombosis in vivo. These results suggest that cathelicidin antimicrobial peptide LL-37 is elevated during SARS-CoV-2 infection, which may induce hypercoagulation in COVID-19 patients by activating coagulation factors.

Recurrent bleeding after rubber band ligation diagnosed as mild hemophilia B: a case report and literature review

Background

Hemophilia is a recessive hemorrhagic disease relevant to X chromosome. In mild hemophilia cases, spontaneous bleeding is rare and the blood clotting function is normal, but severe bleeding may occur after trauma or surgery. Therefore, missed diagnosis of hemophilia before operation may contribute to bleeding after hemorrhoid operation.

Case presentation

A 21-year-old male was hospitalized in the anorectal department because of repeated bleeding after hemorrhoid surgery. Despite several suture hemostasis procedures, the patient still suffered from recurrent bleeding. He had no family history of hemophilia or bleeding tendency, and had not been diagnosed with hemophilia before this admission. The diagnosis of mild hemophilia B was made after further examination of coagulation indexes. By using frozen plasma and coagulation factor complex to supplement coagulation factors, the patient’s bleeding was stopped and he was discharged after 23 days in hospital. During the follow-up, lower-than-normal coagulation factors were still found in him, but no bleeding occurred again.

Conclusions

The undiagnosed patient with mild hemophilia B has an increased risk of bleeding after hemorrhoid surgery because of the consumption of coagulation factors. This case report aims to address the importance of hemophilia screening before operation and reduce the risk of postoperative bleeding. For patients with recurrent bleeding after hemorrhoid surgery, hemophilia should be further excluded. Wound bleeding may recur in hemophilia patients after suture hemostasis. Therefore, prompt supplementation of coagulation factors is needed to help stop bleeding once the diagnosis of hemophilia is made.

Developmental hemostasis in the neonatal period

BACKGROUND

The hemostatic system is complex and evolves continuously since gestation and well into the adult years, in a process known as "developmental hemostasis."

DATA SOURCES

A comprehensive review was performed after an extensive literature search on PubMed/MEDLINE concerning developmental hemostasis during the neonatal period. Relevant cross references were also included.

RESULTS

Although part of a system, each component of the hemostatic system evolves differently, with many displaying both quantitative and qualitative age-related differences. This leads to drastic disparities between the coagulation system of neonates and both other children's and adults', while still maintaining a generally balanced and physiological hemostasis. The motives behind this process remain to be fully elucidated but may be, at least in part, related to non-hemostatic factors.

CONCLUSIONS

Knowledge regarding "developmental hemostasis" is essential for everyone caring for newborns or even children in general and in this review, we describe each hemostatic system component's neonatal characteristics and age-related progression as well as explore some of the possible physiological motives behind the process.

Effect of prolonged storage at 2°C-6°C for 120 h on the coagulation factors of thawed cryoprecipitate: Can we extend its shelf life post thaw beyond 4 h?

BACKGROUND

Cryoprecipitate helps in replenishing important coagulation factors like fibrinogen, Factor VIII and von Willebrand factor without running the risk of volume overload. It is very useful in the treatment of trauma patients with active bleeding and works best when administered early. Extending the shelf life of thawed cryoprecipitate beyond 4 hours enables us to manage inventory better, reduces the burden of demand vs supply as well as minimizes wastage. It can also help in logistically supporting the transfusion services in making cryoprecipitate readily available in mass casualty scenarios (war, natural calamity) in remote locations by reducing the time required for thawing cryoprecipitate and the need for costly storage equipment. AIM: The aim of this study was to compare the levels of Factor VIII, Fibrinogen and von Willebrand factor on thawed cryoprecipitate after prolonged storage for 5 days at a temperature of 2-6°C.

METHODOLOGY

The above mentioned coagulation factors were analyzed in cryoprecipitate at the time of product thaw and again after 120 hours of 2 to 6°C storage using fully automated coagulation analyser (STA Compact Max). All parameters were expressed as Mean ± Standard deviation and were analyzed using paired t-test with level of significance, P < 0.05.

RESULTS

There was a significant decrease in the level of Factor VIII, whereas the levels of fibrinogen and von Willebrand Factor remained stable during the storage period. All the cryoprecipitate units retained factor activities above therapeutic range even after 5 days of storage at 2-6°C.

CONCLUSION

Although the levels of clotting factors are reduced during storage, they are still maintained above the therapeutic range. In scenarios where maintaining frozen cryoprecipitate inventory is a logistical challenge and emergency massive demands of cryoprecipitate are foreseen, the use of pre-thawed cryoprecipitate can be considered as a viable option.

Diabetes concomitant to aortic stenosis is associated with increased expression of NF-κB and more pronounced valve calcification

AIMS/HYPOTHESIS

Type 2 diabetes has been demonstrated to predispose to aortic valve calcification. We investigated whether type 2 diabetes concomitant to aortic stenosis (AS) enhances valvular inflammation and coagulation activation via upregulated expression of NF-κB, with subsequent increased expression of bone morphogenetic protein 2 (BMP-2).

METHODS

In this case-control study, 50 individuals with severe isolated AS and concomitant type 2 diabetes were compared with a control group of 100 individuals without diabetes. The median (IQR) duration of diabetes since diagnosis was 11 (7-18) years, and 36 (72%) individuals had HbA_1c ≥48 mmol/mol (≥6.5%). Stenotic aortic valves obtained during valve replacement surgery served for in loco NF-κB, BMP-2, prothrombin (FII) and active factor X (FXa) immunostaining. In vitro cultures of valve interstitial cells (VICs), isolated from obtained valves were used for mechanistic experiments and PCR investigations.

RESULTS

Diabetic compared with non-diabetic individuals displayed enhanced valvular expression of NF-κB, BMP-2, FII and FXa (all p ≤ 0.001). Moreover, the expression of NF-κB and BMP-2 positively correlated with amounts of valvular FII and FXa. Only in diabetic participants, valvular NF-κB expression was strongly associated with serum levels of HbA_1c, and moderately with fructosamine. Of importance, in diabetic participants, valvular expression of NF-κB correlated with aortic valve area (AVA) and maximal transvalvular pressure gradient. In vitro experiments conducted using VIC cultures revealed that glucose (11 mmol/l) upregulated expression of both NF-κB and BMP-2 (p < 0.001). In VIC cultures treated with glucose in combination with reactive oxygen species (ROS) inhibitor (N-acetyl-L-cysteine), the expression of NF-κB and BMP-2 was significantly suppressed. A comparable effect was observed for VICs cultured with glucose in combination with NF-κB inhibitor (BAY 11-7082), suggesting that high doses of glucose activate oxidative stress leading to proinflammatory actions in VICs. Analysis of mRNA expression in VICs confirmed these findings; glucose caused a 6.9-fold increase in expression of RELA (NF-κB p65 subunit), with the ROS and NF-κB inhibitor reducing the raised expression of RELA by 1.8- and 3.2-fold, respectively.

CONCLUSIONS/INTERPRETATION

Type 2 diabetes enhances in loco inflammation and coagulation activation within stenotic valve leaflets. Increased valvular expression of NF-κB in diabetic individuals is associated not only with serum HbA_1c and fructosamine levels but also with AVA and transvalvular gradient, indicating that strict long-term glycaemic control is needed in AS patients with concomitant type 2 diabetes. This study suggests that maintaining these variables within the normal range may slow the rate of AS progression.

Von Willebrand Disease: Current Status of Diagnosis and Management

Von Willebrand disease (VWD) is a common bleeding disorder, affecting male and female individuals equally, that often manifests in mucosal bleeding. VWD can be secondary to a quantitative (Type 1 and Type 3) or qualitative (Type 2) defects in Von Willebrand factor (VWF). Initial testing includes VWF antigen, as well as a platelet binding assay to differentiate between qualitative and quantitative defects. Further subtyping requires additional testing and is needed to ensure appropriate treatment. Desmopressin, antifibrinolytics, hormonal treatments for heavy menstrual bleeding, and VWF concentrates are commonly used in the treatment of VWD.

Thrombotic activation before and after total hip arthroplasty. A prospective cohort study

Background

Total hip arthroplasty (THA) causes acute blood loss. It may lead to a deficiency in coagulation factors, which, in turn, may lead to increased bleeding during the postoperative period.

Methods

Thirty patients (18 women) with a mean age of 67 years (range: 63–72 years) participated in this prospective diagnostic study. THA was performed without tranexamic acid administration in the perioperative period. Activities of clotting factors II, VIII, X, and fibrinogen concentration were evaluated before surgery, 6 hours after the procedure, 2, 4, and 6 days after the operation. All laboratory tests were performed using ACL TOP 500 CTS analyzer.

Results

No thromboembolic complications were noted during hospitalization. Mean fibrinogen concentration was 366 mg/dL before surgery, which decreased to 311 mg/dL 6 hours after the operation and peaked at 827 mg/dL on the 4th day after the procedure. Activities of factors II and X decreased on the second and fourth days after surgery. Although the activity of factor VIII decreased after the procedure, it remained within the normal range. Increased baseline fibrinogen concentrations were observed in 6 out of 30 (20%) patients. Mean blood loss was 1332 mL (range, 183–2479 mL) and did not correlate with changes in clotting factor activities.

Conclusions

In patients undergoing THA, fibrinogen acts as an acute-phase protein. Activities of clotting factors II and X normalize within 6 days, and although the activity of factor VIII decreases, it remains within the normal range.

Trial registration

The study was pre-registered May 1st, 2020 on ClinicalTrials.gov

Differential effect of statin use on coagulation markers: an active comparative analysis in the NEO study

Background

Statins are a potential treatment for venous thromboembolism (VTE) prophylaxis complementary to conventional anticoagulants without associated bleeding complications. This study aimed to compare pro-thrombotic activities of different classes of lipid-lowering drugs in an active comparator design and determine whether there is a relation between statin versus fibrate/niacin use and pro-coagulant factor outcomes.

Methods

This is a cross-sectional analysis of participants from the Netherlands Epidemiology of Obesity study using any class of lipid-lowering drugs, including any types of statins, niacin, and fibrates. We performed linear regression analyses to determine fibrinogen, factor (F) VIII, FIX, and FXI activity in statins versus fibrate/niacin users and adjusted for age, sex, tobacco smoking, body mass index (BMI), hypertension, diabetes, and prevalent cardiovascular disease.

Results

Among 1043 participants, the mean age was 58.4 ± 5.2 years, 61% were men, and the mean BMI was 31.3 ± 4.5 kg/m². Clinical characteristics were balanced between statin and fibrate/niacin users. Statin users had lower mean FXI (18.3 IU/dL, 95% confidence interval (CI) 9.4 to 27.3) levels compared to fibrate/niacin users. The level of FVIII (15.8 IU/dL, 95% CI − 0.003 to 31.6), and FIX (11.3 IU/dL, 95% CI − 0.4 to 23.2) were lower in statin users than fibrate/niacin users with marginal statistical significance.

Conclusion

Current statin use was associated with lower plasma levels of FXI than fibrate/niacin use. The effects on coagulation factors may, in part, explain the benefit of statin therapy rendered in primary and secondary prevention of VTE.

Drop-of-blood acoustic tweezing technique for integrative turbidimetric and elastometric measurement of blood coagulation

Many patients develop coagulation abnormalities due to chronic and hereditary disorders, infectious disease, blood loss, extracorporeal circulation, and oral anticoagulant misuse. These abnormalities lead to bleeding or thrombotic complications, the risk of which is assessed by coagulation analysis. Current coagulation tests pose safety concerns for neonates and small children due to large sample volume requirement and may be unreliable for patients with coagulopathy. This study introduces a containerless drop-of-blood method for coagulation analysis, termed "integrated quasi-static acoustic tweezing thromboelastometry" (i-QATT™), that addresses these needs. In i-QATT™, a single drop of blood is forced to levitate and deform by the acoustic radiation force. Coagulation-induced changes in drop turbidity and firmness are measured simultaneously at different instants. The parameters describing early, intermediate, and late stages of the coagulation process are evaluated from the resulting graphical outputs. i-QATT™ rapidly (<10 min) detected hyper- and hypo-coagulable states and identified single deficiency in coagulation factors VII, VIII, IX, X, and XIII. The linear relationship (r² > 0.9) was established between fibrinogen concentration and two i-QATT™ parameters: maximum clot firmness and maximum fibrin level. Factor XIII activity was uniquely measured by the fibrin network formation time (r² = 0.9). Reaction time, fibrin formation rate, and time to firm clot formation were linearly correlated with heparin concentration (r² > 0.7). tPA-induced hyperfibrinolysis was detected in the clot firmness output at 10 min. i-QATT™ provides comprehensive coagulation analysis in point-of-care or laboratory settings, well suited to the needs of neonatal and pediatric patients and adult patients with anemia or blood collection issues.

Factor XII deficiency in asymptomatic Saudi population: A retrospective cohort study

Factor XII (FXII) deficiency is a rare genetic blood disorder. It can lead to a higher risk of developing deep vein thrombosis or acquired thrombotic disorders than the general population. This retrospective study evaluated patients who opted for surgery and were found to have abnormal clotting profiles and clotting factors on preoperative routine blood. Patients were included regardless of whether they were symptomatic or asymptomatic. The cohort comprised 115 patients with a mean FXII level of 128.04 ± 36.93%. Two (1.79%) patients, both of whom were women, had FXII levels <60%. The mean FXII level was 58 ± 1.41 (range, 57–59%) in this group. The present study shows the prevalence of FXII in the asymptomatic Saudi population. The results provide the normal range for FXII. The findings of our study provide the basis for diagnosing F XII deficiency in the asymptomatic Saudi population.

Role of crotoxin in coagulation: novel insights into anticoagulant mechanisms and impairment of inflammation-induced coagulation

Background:

Snake venom phospholipases A₂ (svPLA₂) are biologically active toxins, capable of triggering and modulating a wide range of biological functions. Among the svPLA₂s, crotoxin (CTX) has been in the spotlight of bioprospecting research due to its role in modulating immune response and hemostasis. In the present study, novel anticoagulant mechanisms of CTX, and the modulation of inflammation-induced coagulation were investigated.

Methods:

CTX anticoagulant activity was evaluated using platelet poor plasma (PPP) and whole blood (WB), and also using isolated coagulation factors and complexes. The toxin modulation of procoagulant and pro-inflammatory effects was evaluated using the expression of tissue factor (TF) and cytokines in lipopolysaccharide (LPS)-treated peripheral blood mononuclear cells (PBMC) and in WB.

Results:

The results showed that CTX impaired clot formation in both PPP and WB, and was responsible for the inhibition of both intrinsic (TF/factor VIIa) and extrinsic (factor IXa/factor VIIIa) tenase complexes, but not for factor Xa and thrombin alone. In addition, the PLA₂ mitigated the prothrombinase complex by modulating the coagulation phospholipid role in the complex. In regards to the inflammation-coagulation cross talk, the toxin was capable of reducing the production of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, and was followed by decreased levels of TF and procoagulant activity from LPS-treated PBMC either isolated or in WB.

Conclusion:

The results obtained in the present study recognize the toxin as a novel medicinal candidate to be applied in inflammatory diseases with coagulation disorders.

Rise of levels of von Willebrand factor and factor VIII with age: Role of genetic and acquired risk factors

BACKGROUND

Von Willebrand factor (VWF) levels are regulated by genetic and acquired factors. The acquired factors are mostly related to age and could be mediators of the age effect on VWF levels.

OBJECTIVES

To disentangle the role of genetic (sex, blood group) and acquired factors (comorbidities, body mass index, reduced kidney function, hormone use, and inflammation) in regulating von Willebrand factor antigen (VWF:Ag) and factor VIII activity (FVIII:C) levels in the normal population.

METHODS

Analysis were performed in a large population sample (2923 individuals) from the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), after exclusion of individuals with active cancer and women who were pregnant or within nine months postpartum. The increase of VWF:Ag and FVIII:C with age was evaluated by linear regression after the age of 40 years. Analyses were adjusted for acquired factors and stratified for sex and blood group.

RESULTS

VWF:Ag and FVIII:C increased with age: increase per decade of age for VWF:Ag 18 IU/dL (95%CI 15-20) and for FVIII:C 12 IU/dL (95%CI 10-14). After adjustment for acquired factors, the increase per decade was 13 IU/dL (95%CI 10-16) for VWF:Ag and 9 IU/dL (95%CI 6-11) for FVIII:C. The stratified analysis for blood group showed higher increase in the non-O group, but these differences were annulled after adjustment for acquired factors.

CONCLUSIONS

VWF:Ag and FVIII:C increase with age. Carriers of blood group non-O present a steeper increase of VWF:Ag and FVIII:C with age, that is mediated by acquired factors.

Factors predisposing to thrombosis after major joint arthroplasty

BACKGROUND

Total joint arthroplasty is one of the most common options for end stage osteoarthritis of major joints. However, we must take into account that thrombosis after hip/knee arthroplasty may be related to mutations in genes encoding for blood coagulation factors and immune reactions to anticoagulants [heparin-induced thrombocytopenia (HIT)/thrombosis]. Identifying and characterizing genetic risk should help to develop diagnostic strategies or modify anticoagulant options in the search for etiological mechanisms that cause thrombophilia following major orthopedic surgery.

AIM

To evaluate the impact of patients’ coagulation profiles and to study specific pharmacologic factors in the development of post-arthroplasty thrombosis.

METHODS

In 212 (51 male and 161 female) patients that underwent primary total hip arthroplasty (100) or total knee arthroplasty (112) due to osteoarthritis during a period of 1 year, platelet counts and anti-platelet factor 4 (PF4)/heparin antibodies were evaluated pre/postoperatively, and antithrombin III, methylenetetrahydrofolate reductase, factor V and prothrombin gene mutations were evaluated preoperatively. In a minimum follow-up of 3 years, 196 patients receiving either low-molecular-weight heparins (173) or fondaparinux (23) were monitored for the development of thrombocytopenia, anti-PF4/heparin antibodies, HIT, and thrombosis.

RESULTS

Of 196 patients, 32 developed thrombocytopenia (nonsignificant correlation between anticoagulant type and thrombocytopenia, P = 0134.) and 18 developed anti-PF4/heparin antibodies (12/173 for low-molecular-weight heparins and 6/23 for fondaparinux; significant correlation between anticoagulant type and appearance of antibodies, P = 0.005). Odds of antibody emergence: 8.2% greater in patients receiving fondaparinux than low-molecular-weight heparins. Gene mutations in factor II or V (two heterozygotes for both factor V and II) were identified in 15 of 196 patients. Abnormal low protein C and/or S levels were found in 3 of 196 (1.5%) patients, while all patients had normal levels of von Willebrand factor, lupus anticoagulant, and antithrombin III. Four patients developed HIT (insignificant correlation between thrombocytopenia and antibodies) and five developed thrombosis (two had positive antibodies and two were heterozygotes for both factor II & V mutations). Thrombosis was not significantly correlated to platelet counts or HIT. The correlation of thrombosis to antibodies, factor II, factor V was P = 0.076, P = 0.043, P = 0.013, respectively.

CONCLUSION

Screening of coagulation profile, instead of platelet monitoring, is probably the safest way to minimize the risk of post-arthroplasty thrombosis. In addition, fondaparinux can lead to the formation of anti-PF4/heparin antibodies or HIT.

Studies on fragment-based design of allosteric inhibitors of human factor XIa

Human factor XIa (hFXIa) has emerged as an attractive target for development of new anticoagulants that promise higher level of safety. Different strategies have been adopted so far for the design of anti-hFXIa molecules including competitive and non-competitive inhibition. Of these, allosteric dysfunction of hFXIa's active site is especially promising because of the possibility of controlled reduction in activity that may offer a route to safer anticoagulants. In this work, we assess fragment-based design approach to realize a group of novel allosteric hFXIa inhibitors. Starting with our earlier discovery that sulfated quinazolinone (QAO) bind in the heparin-binding site of hFXIa, we developed a group of two dozen dimeric sulfated QAOs with intervening linkers that displayed a progressive variation in inhibition potency. In direct opposition to the traditional wisdom, increasing linker flexibility led to higher potency, which could be explained by computational studies. Sulfated QAO 19S was identified as the most potent and selective inhibitor of hFXIa. Enzyme inhibition studies revealed that 19S utilizes a non-competitive mechanism of action, which was supported by fluorescence studies showing a classic sigmoidal binding profile. Studies with selected mutants of hFXIa indicated that sulfated QAOs bind in heparin-binding site of the catalytic domain of hFXIa. Overall, the approach of fragment-based design offers considerable promise for designing heparin-binding site-directed allosteric inhibitors of hFXIa.

Identification of novel glycosylation events on human serum-derived factor IX

Human Factor IX is a highly post-translationally modified protein that is an important clotting factor in the blood coagulation cascade. Functional deficiencies in Factor IX result in the bleeding disorder haemophilia B, which is treated with plasma-derived or recombinant Factor IX concentrates. Here, we investigated the post-translational modifications of human serum-derived Factor IX and report previously undescribed O-linked monosaccharide compositions at serine 141 and a novel site of glycosylation. At serine 141 we observed two monosaccharide compositions, with HexNAc₁Hex₁NeuAc₂ dominant and a low level of HexNAc₁Hex₁NeuAc₁. This O-linked site lies N-terminal to the first cleavage site for the activation peptide, an important region of the protein that is removed to activate Factor IX. The novel site is an N-linked site in the serine protease domain with low occupancy in a non-canonical consensus motif at asparagine 258, observed with a HexNAc₄Hex₅NeuAc₂ monosaccharide composition attached. This is the first reported instance of a site of modification in the serine protease domain. The description of these glycosylation events provides a basis for future functional studies and contributes to structural characterisation of native Factor IX for the production of effective therapeutic biosimilars and biobetters.

Impact of a goal-directed factor-based coagulation management on thromboembolic events following major trauma

BACKGROUND

A factor-based coagulation management following major trauma is recommended as standard of care by the European Trauma Treatment Guidelines. However, concerns about the thromboembolic risk of this approach are still prevalent. Our study therefore aims to assess if such a haemostatic management is associated with an increased risk for thromboembolic events.

METHODS

In this retrospective observational study carried out at the University Hospital Zurich we compared two three-year periods before (period 1: 2005-2007) and after (period 2: 2012-2014) implementation of a factor-based coagulation algorithm. We included all adult patients following major trauma primarily admitted to the University Hospital Zurich. Thromboembolic events were defined as a new in-hospital appearance of any peripheral thrombosis, arterial embolism, pulmonary embolism, stroke or myocardial infarction. A logistic regression was performed to investigate the association of thromboembolic events with possible confounders such as age, sex, specific Abbreviated Injury Scale (AIS) subgroups, allogeneic blood products, and the coagulation management.

RESULTS

Out of 1138 patients, 772 met the inclusion criteria: 344 patients in period 1 and 428 patients in period 2. Thromboembolic events were present in 25 patients (7.3%) of period 1 and in 42 patients (9.8%) of period 2 (raw OR 1.39, 95% CI 0.83 to 2.33, p = 0.21). Only AIS extremities (adjusted OR 1.26, 95% CI 1.05 to 1.52, p = 0.015) and exposure to allogeneic blood products (adjusted OR 2.39, 95% CI 1.33 to 4.30, p = 0.004) were independently associated with thromboembolic events in the logistic regression, but the factor-based coagulation management was not (adjusted OR 1.60, 95% CI 0.90-2.86, p = 0.11).

CONCLUSION

There is no evidence that a goal-directed, factor-based coagulation management is associated with an increased risk for thromboembolic events following major trauma.

The plasma supply in Germany

There is a demand for self-sufficiency of plasma from the government of the Federal Republic of Germany. To fulfill this, a number of efforts undertaken over the last years. This report describes the current status of the plasma supply in Germany. Data were retrieved from the Paul-Ehrlich-Institute which collects data on the collection and use of blood including plasma according to the German Transfusion Act. Collection of therapeutic plasma showed a slight decline since 2013 but a new peak was observed in 2017. Plasma for fractionation remained almost constant for the last years and about 2 million liters of plasma for fractionation are collected as source plasma. Manufacture of immunoglobulin is steadily increasing to treat patients with immunodeficiencies. Human plasma Factor VIII and IX are still used for treatment of haemophilia in the era of recombinant products. Import and export of plasma for fractionation ensure the supply of plasma derivatives. Targeted fibrinogen supplementation in combination with individualized patient blood management resulted in a decreased use of therapeutic plasma units.

Clotting factors: Clinical biochemistry and their roles as plasma enzymes

The purpose of this review is to describe structure and function of the multiple proteins of the coagulation system and their subcomponent domains. Coagulation is the process by which flowing liquid blood plasma is converted to a soft, viscous gel entrapping the cellular components of blood including red cells and platelets and thereby preventing extravasation of blood. This process is triggered by the minimal proteolysis of plasma fibrinogen. This transforms the latter to sticky fibrin monomers which polymerize into a network. The proteolysis of fibrinogen is a function of the trypsin-like enzyme termed thrombin. Thrombin in turn is activated by a cascade of trypsin-like enzymes that we term coagulation factors. In this review we examine the mechanics of the coagulation cascade with a view to the structure-function relationships of the proteins. We also note that two of the factors have no trypsin like protease domain but are essential cofactors or catalysts for the proteases. This review does not discuss the major role of platelets except to highlight their membrane function with respect to the factors. Coagulation testing is a major part of routine diagnostic clinical pathology. Testing is performed on specimens from individuals either with bleeding or with thrombotic disorders and those on anticoagulant medications. We examine the basic in-vitro laboratory coagulation tests and review the literature comparing the in vitro and in vivo processes. In vitro clinical testing typically utilizes plasma specimens and non-physiological or supraphysiological activators. Because the review focuses on coagulation factor structure, a brief overview of the evolutionary origins of the coagulation system is included.

Contribution of platelets, the coagulation and fibrinolytic systems to cutaneous wound healing

Wound healing is a complex process that consists of multiple phases, each of which are indispensable for adequate repair. Timely initiation and resolution of each of these phases namely, hemostasis, inflammation, proliferation and tissue remodeling, is critical for promoting healing and avoiding excess scar formation. While platelets have long been known to influence the healing process, other components of blood particularly coagulation factors and the fibrinolytic system also contribute to efficient wound repair. This review aims to summarize our current understanding of the role of platelets, the coagulation and fibrinolytic systems in cutaneous wound healing, with a focus on how these components communicate with immune and non-immune cells in the wound microenvironment. We also outline current and potential therapeutic strategies to improve the management of chronic, non-healing wounds.

Cytokine clearance with CytoSorb® during cardiac surgery: a pilot randomized controlled trial

Background

Cardiopulmonary bypass (CPB) is often associated with degrees of complex inflammatory response mediated by various cytokines. This response can, in severe cases, lead to systemic hypotension and organ dysfunction. Cytokine removal might therefore improve outcomes of patients undergoing cardiac surgery. CytoSorb® (Cytosorbents, NJ, USA) is a recent device designed to remove cytokine from the blood using haemoadsorption (HA). This trial aims to evaluate the potential of CytoSorb® to decrease peri-operative cytokine levels in cardiac surgery.

Methods

We have conducted a single-centre pilot randomized controlled trial in 30 patients undergoing elective cardiac surgery and deemed at risk of complications. Patients were randomly allocated to either standard of care (n = 15) or CytoSorb® HA (n = 15) during cardiopulmonary bypass (CPB). Our primary outcome was the difference between the two groups in cytokines levels (IL-1a, IL-1b, IL-2, IL-4, IL-5, IL-6, IL-10, TNF-α, IFN-γ, MCP-1) measured at anaesthesia induction, at the end of CPB, as well as 6 and 24 h post-CPB initiation. In a consecutive subgroup of patients (10 in HA group, 11 in control group), we performed cross-adsorber as well as serial measurements of coagulation factors’ activity (antithrombin, von Willebrand factor, factor II, V, VIII, IX, XI, and XII).

Results

Both groups were similar in terms of baseline and peri-operative characteristics. CytoSorb® HA during CPB was not associated with an increased incidence of adverse event. The procedure did not result in significant coagulation factors’ adsorption but only some signs of coagulation activation. However, the intervention was associated neither with a decrease in pro- or anti-inflammatory cytokine levels nor with any improvement in relevant clinical outcomes.

Conclusions

CytoSorb® HA during CPB was not associated with a decrease in pro- or anti-inflammatory cytokines nor with an improvement in relevant clinical outcomes. The procedure was feasible and safe. Further studies should evaluate the efficacy of CytoSorb® HA in other clinical contexts.

Trial registration

ClinicalTrials.gov NCT02775123. Registered 17 May 2016.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2399-4) contains supplementary material, which is available to authorized users.

Fluid resuscitation with 0.9% saline alters haemostasis in an ovine model of endotoxemic shock

INTRODUCTION

Fluid resuscitation is a cornerstone of severe sepsis management, however there are many uncertainties surrounding the type and volume of fluid that is administered. The entire spectrum of coagulopathies can be seen in sepsis, from asymptomatic aberrations to fulminant disseminated intravascular coagulation (DIC). The aim of this study was to determine if fluid resuscitation with saline contributes to the haemostatic derangements in an ovine model of endotoxemic shock.

MATERIALS AND METHODS

Twenty-one adult female sheep were randomly divided into no endotoxemia (n = 5) or endotoxemia groups (n = 16) with an escalating dose of lipopolysaccharide (LPS) up to 4 μg/kg/h administered to achieve a mean arterial pressure below 60 mmHg. Endotoxemia sheep received either no bolus fluid resuscitation (n = 8) or a 0.9% saline bolus (40 mL/kg over 60 min) (n = 8). No endotoxemia, saline only animals (n = 5) underwent fluid resuscitation with a 0.9% bolus of saline as detailed above. Hemodynamic support with vasopressors was initiated if needed, to maintain a mean arterial pressure (MAP) of 60-65 mm Hg in all the groups.

RESULTS

Rotational thromboelastometry (ROTEM®) and conventional coagulation biomarker tests demonstrated sepsis induced derangements to secondary haemostasis. This effect was exacerbated by saline fluid resuscitation, with low pH (p = 0.036), delayed clot initiation and formation together with deficiencies in naturally occurring anti-coagulants antithrombin (p = 0.027) and Protein C (p = 0.001).

CONCLUSIONS

Endotoxemia impairs secondary haemostasis and induces changes in the intrinsic, extrinsic and anti-coagulant pathways. These changes to haemostasis are exacerbated following resuscitation with 0.9% saline, a commonly used crystalloid in clinical settings.

Evaluation of Coagulation Factors Activity in Different Types of Plasma Preparations

Fresh frozen plasma (FFP) is a crucial substitute therapy in management of bleeding; producing plasma from whole blood stored within 24 h offers operational flexibility and leukocyte filtration significantly reduce transfusion reactions, it is necessary to consider the impact of these plasma preparations on clotting factors activity. Total of 75 plasma samples collected from 25 blood donors distributed as 3 groups; FFP (Group A), leukocyte filtrated FFP (Group B) and plasma frozen within 24 h i.e. PF24 (Group C), for all samples prothrombin time (PT), INR, (APTT), Factors V, VII, VIII, IX levels and Fibrinogen were done, also comparing coagulation factors levels in FFP in different blood groups. There were significant difference between three groups in (PT), INR and (APTT): (P = 0.00). Concerning Factor VII: significant difference (P = 0.03) between the three groups, FFP had a significantly higher level of FVII compared to filtrated FFP (98.92 vs. 82.52%; P = 0.02), while no significant difference between FFP and PF24 was detected (P = 0.76). Factor VIII: had significant difference (P = 0.00) between the three groups, FFP and Filtrated FFP had no significant difference regarding level of FVIII (P = 0.72), but FFP had significantly higher level of FVIII compared to PF24 (P < 0.05). Concerning Fibrinogen level: no significant difference between FFP and filtrated FFP (P = 0.99), while FFP had a higher level versus PF24 (P < 0.05). On the Contrary, no significant difference between three groups in Factor V: (P = 0.22) and Factor IX: (P = 0.12). ABO blood group effect on studied parameters in FFP: FVIII was statistically higher in Non-O blood group (P = 0.03), other factors had no statistical differences (P > 0.05). The leukocyte filtration of FFP did not affect the majority of coagulation factors activities, although FVII level was reduced, it stills enough for surgical hemostasis. The PF24 resulted in reduced FVIII and fibrinogen levels but no significant changes in FV, FVII or FIX, thus, can be used for FFP indications except that specifically requiring replacement of FVIII and/or fibrinogen as Hemophilia or DIC. No significant difference in coagulation factors of FFP between O and non-O blood groups except FVIII that was reduced in O blood group.

Management of rare coagulation disorders in 2018

Rare bleeding disorders (RBDs) comprise inherited deficiencies of factors I (fibrinogen), II (prothrombin), V, VII, X, XI, and XIII as well as combined factor V + VIII and vitamin K-dependent factors. They represent 3-5% of all congenital bleeding disorders and are usually transmitted as autosomal recessive traits. These disorders often manifest during childhood and have varied clinical presentations from mucocutaneous bleeding to life-threatening symptoms such as central nervous system and gastrointestinal bleeding. Bleeding manifestations generally vary within the same RBD and may also vary from 1 RBD to the other. Laboratory diagnosis is based on coagulation screening tests and specific factor assays, with molecular techniques providing diagnostic accuracy and enabling prenatal counseling. The approach to treatment of bleeding episodes and invasive procedures needs to be individualized and depends on the severity, frequency and procedure-related risk of bleeding. The first line of treatment of RBDs is replacement of the deficient factor, using specific plasma-derived or recombinant products and using fresh frozen plasma or cryoprecipitate when specific products are not available or in resource-limited countries. Prophylaxis may be considered in individuals with recurrent serious bleeding and especially after life-threatening bleeding episodes. Novel no-replacement strategies promoting hemostasis by through different mechanisms need to be studied in RBDs as alternative therapeutic options.

Peroxisome proliferator-activated receptor α attenuates high-cholesterol diet-induced toxicity and pro-thrombotic effects in mice

Peroxisome proliferator-activated receptor α (PPARα) is involved in the regulation of fatty acid and cholesterol metabolism. A high-cholesterol (HC) diet increases the risk of developing cardiovascular diseases (CVD); however, it is unclear whether the toxic effects of cholesterol involve changes in thrombotic factor expression, and whether PPARα is necessary for such effects. To investigate this possibility, we fed a HC diet to wild-type (WT) and Ppara-null mice and measured cholesterol and triglyceride contents, liver histology, serum/plasma levels of coagulation factors, hepatic expression of the coagulation factors, liver/serum sulfatide levels, hepatic sulfatide metabolism, hepatic expression of lipid transporters, and hepatic oxidative stress and its relating enzymes. In Ppara-null mice, the HC diet caused triglyceride accumulation and exacerbated inflammation and oxidative stress in liver, increased levels of coagulation factors, including tissue factor, plasminogen activator inhibitor-1 and carboxypeptidase B2 in blood and liver, and decreased levels of anti-thrombotic sulfatides in serum and liver. These changes were much less marked in WT mice. These findings imply that cholesterol overload exerts its toxic effects at least in part by enhancing thrombosis, secondary to abnormal hepatic lipid metabolism, inflammation, and oxidative stress. Moreover, we reveal for the first time that PPARα can attenuate these toxic effects by transcriptional regulation of coagulation factors and sulfatides, in addition to its known effects of controlling lipid homeostasis and suppressing inflammation and oxidative stress. Therapies aimed at activating PPARα might prevent HC diet-induced CVD through modulating various pro- and anti-thrombotic factors.

Protease-activated receptors are potential regulators in the development of arterial endofibrosis in high-performance athletes

OBJECTIVE

High-performance athletes can develop symptomatic arterial flow restriction during exercise caused by endofibrosis. The pathogenesis is poorly understood; however, coagulation enzymes, such as tissue factor (TF) and coagulation factor Xa, might contribute to the fibrotic process, which is mainly regulated through activation of protease-activated receptors (PARs). Therefore, the aim of this explorative study was to evaluate the presence of coagulation factors and PARs in endofibrotic tissue, which might be indicative of their potential role in the natural development of endofibrosis.

METHODS

External iliac arterial specimens with endofibrosis (n = 19) were collected during surgical interventions. As control, arterial segments of the external iliac artery (n = 20) were collected post mortem from individuals with no medical history of cardiovascular disease who donated their body to medical science. Arteries were paraffinized and cut in tissue sections for immunohistochemical analysis. Positive staining within lesions was determined with ImageJ software (National Institutes of Health, Bethesda, Md).

RESULTS

Endofibrotic segments contained a neointima, causing intraluminal stenosis, which was highly positive for collagen (+150%; P < .01) and elastin (+148%; P < .01) in comparison with controls. Intriguingly, endofibrosis was not limited to the intima because collagen (+213%) and elastin (+215%) were also significantly elevated in the media layer of endofibrotic segments. These findings were accompanied by significantly increased α-smooth muscle actin-positive cells, morphologically compatible with the presence of myofibroblasts. In addition, PAR1 and PAR4 and the membrane receptor TF were increased as well as coagulation factor X.

CONCLUSIONS

We showed that myofibroblasts and the accompanying collagen and elastin synthesis might be key factors in the development of endofibrosis. The special association with increased presence of PARs, factor X, and TF suggests that protease-mediated cell signaling could be a contributing component in the mechanisms leading to endofibrosis.

Calibration of the 7th British Working Standard for factors II, IX and X, concentrate

Seven laboratories from 5 different countries participated in the calibration of the 7th British Working Standard (BWS) for blood coagulation factors II, IX and X. The candidate, 15/182, was assayed for Factors II and X potencies against the 4th International Standard (IS) for Factors II and X, Concentrate (11/126) and for Factor IX potency against the 5th IS for Factor IX, Concentrate (14/148). Intra-laboratory GCVs for all 3 factors were less than 10%, with the majority less than 5%. Inter-laboratory GCVs were 3.4%, 3.2% and 2.3% for FII, IX and X respectively. All participants agreed with the value assigned and preparation 15/182 was established by NIBSC in October 2017 as the 7th BWS for FII, IX, X Concentrate with potencies of 6.0 IU/ampoule, 6.7 IU/ampoule and 4.9 IU/ampoule for FII, IX and X respectively.

Platelet activation and aggregation after aneurysmal subarachnoid hemorrhage

Background

Endovascular techniques have proven beneficial in the treatment of aneurysmal subarachnoid hemorrhage (aSAH), but with high risk of arterial clotting, emboli and dissection. Platelet activation and alterations in hemostasis may contribute to these complications. We investigated platelet activation and aggregation pathways in aSAH patients who underwent endovascular treatment.

Methods

Two blood samples were taken, in the early days after bleeding and during the period at risk of vasospasm. We studied platelet activation through the expression of GpIIbIIIa and P-selectin as well as aggregation rate in the presence of agonists. Platelets from aSAH patients were compared with those from orthopedic postoperative patients (POSTOP).

Results

Platelets in aSAH were initially spontaneously activated and remained so over time. aSAH platelets were further activated with rapid aggregation in the presence of agonists, particularly ADP, with behavior comparable to POSTOP platelets.

Conclusions

aSAH platelets showed prolonged increases in activation and aggregation. Therapies targeting the ADP pathway might reduce the risk of clotting and ischemic events in this context among patients requiring multiple endovascular procedures.

Trial registration

Not applicable.

Electronic supplementary material

The online version of this article (10.1186/s12883-018-1062-z) contains supplementary material, which is available to authorized users.

Effects of bacterial translocation on hemodynamic and coagulation parameters during living-donor liver transplant

BACKGROUND

Bacterial translocation (BT) has been proposed as a trigger for stimulation of the immune system with consequent hemodynamic alteration in patients with liver cirrhosis. However, no information is available regarding its hemodynamic and coagulation consequences during liver transplantation.

METHODS

We screened 30 consecutive adult patients undergoing living-donor liver transplant for the presence of BT. Bacterial DNA, Anti factor Xa (aFXa), thromboelastometry, tumor necrosis factor-α TNF-α, and interleukin-17 (IL-17) values were measured in sera before induction of anesthesia. Systemic hemodynamic data were recorded throughout the procedures.

RESULTS

Bacterial DNA was detected in 10 patients (33%) (bactDNA(+)). Demographic, clinical, and hemodynamic data were similar in patients with presence or absence of bacterial DNA. BactDNA(+) patients showed significantly higher circulating values of TNF-α and IL-17, and had significantly higher clotting times and clot formation times as well as significantly lower alpha angle and maximal clot firmness than bactDNA(-) patients, P < 0.05. We found no statistically significant difference in aFXa between the groups, P = 0.4. Additionally, 4 patients in each group needed vasopressor agents, P = 0.2. And, the amount of transfused blood and blood products used were similar between both groups.

CONCLUSION

Bacterial translocation was found in one-third of patients at the time of transplantation and was largely associated with increased markers of inflammation along with decreased activity of coagulation factors.

TRIAL REGISTRATION

Trial Registration Number: NCT03230214 . (Retrospective registered). Initial registration date was 20/7/2017.

Transcriptional profiling of liver in riboflavin-deficient chicken embryos explains impaired lipid utilization, energy depletion, massive hemorrhaging, and delayed feathering

BACKGROUND

A strain of Leghorn chickens (rd/rd), unable to produce a functional riboflavin-binding protein, lays riboflavin-deficient eggs, in which all embryos suddenly die at mid-incubation (days 13-15). This malady, caused by riboflavin deficiency, leads to excessive lipid accumulation in liver, impaired β-oxidation of lipid, and severe hypoglycemia prior to death. We have used high-density chicken microarrays for time-course transcriptional scans of liver in chicken embryos between days 9-15 during this riboflavin-deficiency-induced metabolic catastrophe. For comparison, half of rd/rd embryos (n = 16) were rescued from this calamity by injection of riboflavin just prior to incubation of fertile eggs from rd/rd hens.

RESULTS

No significant differences were found between hepatic transcriptomes of riboflavin-deficient and riboflavin-rescued embryos at the first two ages (days 9 and 11). Overall, we found a 3.2-fold increase in the number of differentially expressed hepatic genes between day 13 (231 genes) and day 15 (734 genes). Higher expression of genes encoding the chicken flavoproteome was more evident in rescued- (15 genes) than in deficient-embryos (4 genes) at day 15. Diminished activity of flavin-dependent enzymes in riboflavin-deficient embryos blocks catabolism of yolk lipids, which normally serves as the predominant source of energy required for embryonic development.

CONCLUSIONS

Riboflavin deficiency in mid-stage embryos leads to reduced expression of numerous genes controlling critical functions, including β-oxidation of lipids, blood coagulation and feathering. Surprisingly, reduced expression of feather keratin 1 was found in liver of riboflavin-deficient embryos at e15, which could be related to their delayed feathering and sparse clubbed down. A large number of genes are expressed at higher levels in liver of riboflavin-deficient embryos; these up-regulated genes control lipid storage/transport, gluconeogenesis, ketogenesis, protein catabolism/ubiquitination and cell death.

[Coagulation factors and multiple sclerosis : Key factors in the pathogenesis?]

Environmental factors and genetic predisposition influence the individual risk to develop multiple sclerosis (MS). Preclinical results in animal models of MS, such as experimental autoimmune encephalomyelitis (EAE), prove a significant contribution of the corpuscular and plasmatic coagulation system for the severity of MS. It was recently shown that key molecules of the coagulation cascade, such as fibrinogen, thrombin and factor XII can influence neuroinflammatory disorders such as MS. The inhibition of both fibrinogen and factor XII led to a significantly improved disease course in animal models. Furthermore, in patients suffering from MS a dysregulation of diverse coagulation factors was demonstrated. The precise role of these changes for the pathogenesis of MS remains to be clarified. Nonetheless, the identification of molecular mechanisms between inflammation and the coagulation cascade might provide completely new perspectives for the therapy of MS; however, as most of the currently available data were obtained from animal models, this knowledge must be interpreted with an adequate degree of caution.

In Vitro Assessment of Nanoparticle Effects on Blood Coagulation

Blood clotting is a complex process which involves both cellular and biochemical components. The key cellular players in the blood clotting process are thrombocytes or platelets. Other cells, including leukocytes and endothelial cells, contribute to clotting by expressing the so-called pro-coagulant activity (PCA) complex on their surface. The biochemical component of blood clotting is represented by the plasma coagulation cascade, which includes plasma proteins also known as coagulation factors. The coordinated interaction between platelets, leukocytes, endothelial cells, and plasma coagulation factors is necessary for maintaining hemostasis and for preventing excessive bleeding. Undesirable activation of all or some of these components may lead to pathological blood coagulation and life-threatening conditions such as consumptive coagulopathy or disseminated intravascular coagulation (DIC). In contrast, unintended inhibition of the coagulation pathways may lead to hemorrhage. Thrombogenicity is the property of a test material to induce blood coagulation by affecting one or more elements of the clotting process. Anticoagulant activity refers to the property of a test material to inhibit coagulation. The tendency to cause platelet aggregation, perturb plasma coagulation, and induce leukocyte PCA can serve as an in vitro measure of a nanomaterial's likelihood to be pro- or anticoagulant in vivo. This chapter describes three procedures for in vitro analyses of platelet aggregation, plasma coagulation time, and activation of leukocyte PCA. Platelet aggregation and plasma coagulation procedures have been described earlier. The revision here includes updated details about nanoparticle sample preparation, selection of nanoparticle concentration for the in vitro study, and updated details about assay controls. The chapter is expanded to describe a method for the leukocyte PCA analysis and case studies demonstrating the performance of these in vitro assays.