Fibrinogen as a risk factor for stroke and myocardial infarction

Association of fibrinogen αE, fibrinogen γ', and sialylated fibrinogen with development of ischemic stroke in patients with recently diagnosed type 2 diabetes

BACKGROUND

Stroke is a major cause of death globally, especially in type 2 diabetes (T2D) patients. Fibrinogen is known to predict stroke risk, but fibrinogen is a highly variable protein and we hypothesized that fibrinogen variants can improve stroke prediction.

OBJECTIVES

We aimed to investigate the association of total fibrinogen and fibrinogen variants with risk of ischemic stroke in T2D patients.

METHODS

In a nested case-control study with a median follow-up of 4.1 years, we included 144 T2D patients with ischemic stroke (cases) and 144 matched T2D patients without ischemic stroke (controls). We measured total fibrinogen, absolute, and relative levels of 3 fibrinogen variants (fibrinogen αE, fibrinogen γ', and sialylated fibrinogen) and compared levels between cases and controls. We used logistic regression to determine the association with stroke risk.

RESULTS

Total fibrinogen and absolute levels of fibrinogen αE, fibrinogen γ', and sialylated fibrinogen were higher in stroke cases than controls. Absolute levels of fibrinogen positively associated with risk of stroke for total fibrinogen (highest vs lowest tertile; adjusted odds ratio (OR), 1.9 [95% CI, 0.9-4.2]), fibrinogen γ' (OR, 1.8 [0.8-3.8]), and sialylated fibrinogen (OR, 2.5 [1.1-5.8]). Relative levels of fibrinogen variants did not convincingly associate with stroke risk.

CONCLUSION

Patients with T2D who developed stroke had increased levels of total fibrinogen, fibrinogen αE, fibrinogen γ', and sialylated fibrinogen compared with T2D controls. Total fibrinogen and absolute, but not relative, levels of fibrinogen γ' and sialylated fibrinogen prospectively associated with a 2-fold increased risk of ischemic stroke.

Biomarkers in coronary artery disease: systematic review and meta-analysis

INTRODUCTION

Little information exists regarding the detection of early coronary heart disease protein biomarkers. The aim of this study was to investigate several potential candidates.

METHODS

Systematic review was carried out followed by meta-analysis.

RESULTS

The standardized mean difference (95% confidence intervals) for each comparison was: Troponins 2.31 (1.18, 3.4), iL-6 1.3 (0.8, 1.81), fibrinogen 1.55 (1.16, 1.94), NT-proBNP 1.05 (0.72, 1.38), lipoprotein a 0.75 (0.48, 1.03) osteoprotegerin 0.92 (0.23, 1.62), VCAM-1 1.53 (0.87, 2.18), pentraxin 3 0.87 (-0.13, 1.87), PAI-1 2.51 (-0.65, 5.66) MMP9 1.25 (0.36, 2.14), MCP-1 1.99 (1.12, 2.85) and adiponectin -1.11 (-1.49, -0.73).

CONCLUSION

Multiple biomarkers that could potentially be used for the early detection of coronary heart disease were identified.

Leveraging Mendelian randomization to inform drug discovery and development for ischemic stroke

Discovery and development of efficacious and safe pharmacological therapies is fraught with challenges. As proteins constitute the majority of drug targets and are encoded by genes, naturally occurring genetic variation within populations can provide valuable insights to inform drug discovery and development efforts. The drug target Mendelian randomization (MR) paradigm leverages these principles to investigate the causal effects of drug targets in humans. This review examines the application of drug target MR in informing the efficacy and development of therapeutics for ischemic stroke prevention and treatment. We consider applications of MR for existing and novel treatment strategies, including targeting blood pressure, lipid metabolism, coagulation, inflammation and glycemic control. Several of these genetically supported targets are under evaluation in late-stage clinical trials. Methodological limitations of drug target MR are addressed, followed by an outline of future research directions. We anticipate that careful application of drug target MR will enhance the efficiency of drug development for ischemic stroke, consequently accelerating the delivery of effective medications to patients.

High Fibrinogen Levels with Diabetes Mellitus are Associated with All-Cause and Cardiovascular Mortality in Patients with End-Stage Renal Disease and Acute Coronary Syndrome

Objective

As a biomarker of inflammation and a core component in the coagulation pathway, fibrinogen contributes to atherosclerosis and subsequent adverse cardiovascular events and is modified by the occurrence of diabetes mellitus. However, the association between fibrinogen, diabetes status, and mortality in patients with end-stage renal disease (ESRD) and acute coronary syndrome (ACS) remains scarce.

Methods

A multi-center cohort study enrolled 1079 patients with ESRD and ACS between January 2015 and June 2021. Patients were classified into three groups based on fibrinogen tertiles and were further categorized by diabetes status. The primary outcome was all-cause mortality, while the secondary outcome was cardiovascular mortality.

Results

During a median 21.5 months of follow-up, 386 cases of all-cause mortality were recorded, including 262 cases of cardiovascular mortality. Multivariable Cox regression model revealed that patients with the third tertile of fibrinogen and those with diabetes experienced a significantly increased risk of all-cause mortality (fibrinogen: hazard ratio [HR], 1.70; 95% confidence interval [CI], 1.32-2.19; diabetes: HR, 1.36; 95% CI, 1.10-1.68). When patients were stratified by both fibrinogen levels and diabetes status, patients in the third fibrinogen tertile with diabetes had the highest risk of all-cause mortality (HR 2.43, 95% CI 1.69-3.48) compared to those in the first fibrinogen tertile without diabetes. Similar associations were observed for cardiovascular mortality. Notably, incorporating the combined fibrinogen and diabetes status into the Global Registry of Acute Coronary Events (GRACE) score or baseline risk model led to significant improvements in the C-statistics for predicting mortality, surpassing the advancements achieved with any single biomarker.

Conclusion

In patients with ESRD and ACS, elevated fibrinogen and diabetes were associated with an increased risk of all-cause and cardiovascular mortality. Categorizing patients based on fibrinogen levels and diabetes status could provide valuable information for risk stratification of these patients.

Regulation of fibrinogen synthesis

The plasma protein fibrinogen is encoded by 3 structural genes (FGA, FGB, and FGG) that are transcribed to mRNA, spliced, and translated to 3 polypeptide chains (Aα, Bβ, and γ, respectively). These chains are targeted for secretion, decorated with post-translational modifications, and assembled into a hexameric "dimer of trimers" (AαBβγ)2. Fully assembled fibrinogen is secreted into the blood as a 340 kDa glycoprotein. Fibrinogen is one of the most prevalent coagulation proteins in blood, and its expression is induced by inflammatory cytokines, wherein circulating fibrinogen levels may increase up to 3-fold during acute inflammatory events. Abnormal levels of circulating fibrinogen are associated with bleeding and thrombotic disorders, as well as several inflammatory diseases. Notably, therapeutic strategies to modulate fibrinogen levels have shown promise in experimental models of disease. Herein, we review pathways mediating fibrinogen synthesis, from gene expression to secretion. Knowledge of these mechanisms may lead to the identification of biomarkers and new therapeutic targets to modulate fibrinogen in health and disease.

Postmortem Immunohistochemical Findings in Early Acute Myocardial Infarction: A Systematic Review

The diagnosis of early acute myocardial infarction is of particular importance in forensic practice considering the frequency of sudden cardiac death and the difficulty of positively identifying it through classical histological methods if survival is less than 6 h. This article aims to analyze potential immunohistochemical markers that could be useful in diagnosing acute myocardial infarction within the first 6 h of its onset. We conducted an extensive evaluation of the literature according to the PRISMA guidelines for reporting systematic literature reviews. We searched the Web of Science and PubMed databases from their inception to 2023 using the following keywords: "myocardial infarction" and "immunohistochemistry". Fifteen studies met the inclusion criteria. Immunohistochemical markers as complement factors and CD59, myoglobin, fibrinogen, desmin, tumor necrosis factor alpha (TNF-α), P-38, JNK (Jun N Terminal Kinase), transforming growth factor β1 (TGF-β1), cardiac troponins, fibronectin, H-FABP (heart fatty acid binding protein), dityrosine, fibronectin, CD15, IL-1β, IL-6, IL-15, IL-8, MCP-1, ICAM-1, CD18, and tryptase can be used to identify the first six hours of acute myocardial infarction. These markers are mostly studied in experimental animal models. It is necessary to conduct extensive studies on human myocardial tissue fragments, which will involve the analysis of several immunohistochemical markers and careful analysis of the available data on perimortem events, resuscitation, and postmortem intervals in the context of a uniform laboratory methodology.

Diagnosing cancer-associated ischemic stroke: A systematic review of hematological biomarkers

BACKGROUND AND AIM

Patients suffering from cancer are reported to have an increased risk of ischemic stroke (IS). We aimed to identify cancer-associated biomarkers found to differentiate between IS associated with cancer from those not associated with cancer.

SUMMARY OF REVIEW

We performed a systematic search of PubMed and EMBASE databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The study is reported in PROSPERO (#CRD42022355129). In total, 5563 papers were screened, of which 49 papers were included. Seven biomarkers were identified which had the potential to differentiate between patients who had cancer or stroke or both conditions. D-dimer was the most frequently monitored biomarker, and high levels were significantly associated with cancer-related strokes in (42/44) studies. Fibrinogen was significantly associated with cancer-related strokes in 11/27 studies. A higher level of C-reactive protein, investigated in 19 studies, was associated with cancer-related strokes, but conclusive multivariate analysis was not performed. Finally, the four cancer-associated antigens CA125, CA153, CA199, and carcinoembryonic antigen were only reported on in three to six studies, respectively. These studies all originated from the Guangxi province in China. CA125 was associated with an increased risk of IS in four of six studies.

CONCLUSION

Increased D-dimer seems associated with cancer-related IS. CRP may also be a candidate as a cancer-associated stroke biomarker, but this requires further verification. Fibrinogen and the more specific cancer biomarkers have not yet been proven helpful for detecting cancer-related strokes.

Ramadan intermittent fasting is associated with improved anticoagulant activity among healthy people: a case-control study

Data on the pathophysiological mechanisms of hemostatic alterations in the thrombotic events that occur during Ramadan intermittent fasting (RIF), particularly in the natural coagulation inhibitors, are very limited. Thus, our objective was to evaluate the effect of RIF on the natural anticoagulants level, antithrombin, protein C, and total and free protein S (PS) in healthy participants. Participants were divided into two groups. Group I consisted of 29 healthy fasting participants whose blood samples were taken after 20 days of fasting. Group II included 40 healthy non-fasting participants whose blood samples were taken 2-4 weeks before the month of Ramadan. Coagulation screening tests including prothrombin time (PT), activated partial thromboplastin time (APTT) and plasma fibrinogen level, natural anticoagulants; antithrombin, protein C, free and total PS and C4 binding protein (C4BP) levels were evaluated in the two groups. High levels of total and free PS without change in antithrombin, protein C, and C4BP levels were noted in the fasting group as compared with non-fasting ones (p < 0.05). PT and APTT showed no difference between the two groups. However, the fibrinogen level was higher in the fasting group. In conclusion, RIF was found to be associated with improved anticoagulant activity in healthy participants, which may provide temporal physiological protection against the development of thrombosis in healthy fasting people.

Whole Blood Viscosity and Cerebral Blood Flow in Acute Ischemic Stroke

Existing effective treatments for ischemic stroke restore blood supply to the ischemic region using thrombolysis or mechanical removal of clot. However, it is increasingly recognized that successful removal of occlusive thrombus from the large artery-recanalization, may not always be accompanied by successful restoration of blood flow to the downstream tissues-reperfusion. Ultimately, brain tissue survival depends on cerebral perfusion, and a functioning microcirculation. Because capillary diameter is often equal to or smaller than an erythrocyte, microcirculation is largely dependent on erythrocyte rheological (hemorheological) factors such as whole blood viscosity (WBV). Several studies in the past have demonstrated elevated WBV in stroke compared with healthy controls. Also, elevated WBV has shown to be an independent risk factor for stroke. Elevated WBV leads to endothelial dysfunction, decreases nitric oxide-dependent flow-mediated vasodilation, and promotes hemostatic alterations/thrombosis, all leading to microcirculation sludging. Compromised microcirculation further leads to decreased cerebral perfusion. Hence, modulating WBV through pharmacological agents might be beneficial to improve cerebral perfusion in stroke. This review discusses the effect of elevated WBV on endothelial function, hemostatic alterations, and thrombosis leading to reduced cerebral perfusion in stroke.

Nonlinear association of fibrinogen levels with functional prognosis in patients with acute ischemic stroke: a prospective cohort study

OBJECTIVE

Fibrinogen, essential in primary hemostasis, platelet aggregation, and leukocyte-endothelial interactions, is also associated with a heightened risk of acute ischemic stroke (AIS). However, its influence on AIS patient outcomes is unclear. This study examines the correlation between fibrinogen levels and the risk of unfavorable outcomes three months post-AIS.

METHODS

This is a secondary analysis of a prospective cohort study conducted in Korea. The sample consisted of 1851 AIS patients who received treatment at a Korean hospital between January 2010 and December 2016. Statistical models were established to understand the relationship between fibrinogen levels(mg/dL) and unfavorable outcomes(mRs ≥ 3), including logistic regression models, Generalized Additive Models (GAM), and smooth curve fitting (penalized splines). The log-likelihood ratio test has been utilized to evaluate the best fit. To ensure the robustness of the results, sensitivity analyses were conducted by reanalyzing the relationship after excluding participants with TG > 200 mg/dl and BMI > 25 kg/m2. Subgroup analyses were also performed to assess whether influencing factors modify the association between fibrinogen levels and unfavorable outcomes.

RESULTS

After adjusting for multiple covariates including age, BMI, sex, LDL-c, TG, HGB, HDL-c, BUN, FPG, ALB, PLT, AF, hypertension, smoking, DM, mRs score at admission, the binary logistic regression model demonstrated revealed a significant positive association between fibrinogen levels and the risk of unfavorable outcomes in AIS patients (OR = 1.215, 95% CI: 1.032-1.429, p = 0.019). Sensitivity analyses supported these findings, with similar ORs observed in subsets of patients with TG < 200 mg/dL (OR = 1.221, 95% CI: 1.036-1.440) and BMI < 25 kg/m2 (OR = 1.259, 95% CI: 1.051-1.509). Additionally, the relationship between fibrinogen levels and outcomes was nonlinear, with a critical threshold of 2.74 g/L. Below the inflection point, the OR for unfavorable outcomes was 0.666 ((95% CI: 0.360, 1.233, p = 0.196), whereas above it, the OR increased to 1.374 (95% CI: 1.138, 1.659).

CONCLUSIONS

This study has provided evidence of a positive and nonlinear correlation between fibrinogen levels and 3-month poor functional outcomes in patients with AIS. When fibrinogen levels exceeded 2.74 g/L, a significant and positive association was observed with the risk of poor outcomes. This study provides a further reference for optimizing rehabilitation exercises and facilitating clinical counseling in patients with acute ischemic stroke.

Mice expressing nonpolymerizable fibrinogen have reduced arterial and venous thrombosis with preserved hemostasis

ABSTRACT

Elevated circulating fibrinogen levels correlate with increased risk for both cardiovascular and venous thromboembolic diseases. In vitro studies show that formation of a highly dense fibrin matrix is a major determinant of clot structure and stability. Here, we analyzed the impact of nonpolymerizable fibrinogen on arterial and venous thrombosis as well as hemostasis in vivo using FgaEK mice that express normal levels of a fibrinogen that cannot be cleaved by thrombin. In a model of carotid artery thrombosis, FgaWT/EK and FgaEK/EK mice were protected from occlusion with 4% ferric chloride (FeCl3) challenges compared with wild-type (FgaWT/WT) mice, but this protection was lost, with injuries driven by higher concentrations of FeCl3. In contrast, fibrinogen-deficient (Fga-/-) mice showed no evidence of occlusion, even with high-concentration FeCl3 challenge. Fibrinogen-dependent platelet aggregation and intraplatelet fibrinogen content were similar in FgaWT/WT, FgaWT/EK, and FgaEK/EK mice, consistent with preserved fibrinogen-platelet interactions that support arterial thrombosis with severe challenge. In an inferior vena cava stasis model of venous thrombosis, FgaEK/EK mice had near complete protection from thrombus formation. FgaWT/EK mice also displayed reduced thrombus incidence and a significant reduction in thrombus mass relative to FgaWT/WT mice after inferior vena cava stasis, suggesting that partial expression of nonpolymerizable fibrinogen was sufficient for conferring protection. Notably, FgaWT/EK and FgaEK/EK mice had preserved hemostasis in multiple models as well as normal wound healing times after skin incision, unlike Fga-/- mice that displayed significant bleeding and delayed healing. These findings indicate that a nonpolymerizable fibrinogen variant can significantly suppress occlusive thrombosis while preserving hemostatic potential in vivo.

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 shared genetic risk architecture of neurological and psychiatric disorders: a genome-wide analysis

While neurological and psychiatric disorders have historically been considered to reflect distinct pathogenic entities, recent findings suggest shared pathobiological mechanisms. However, the extent to which these heritable disorders share genetic influences remains unclear. Here, we performed a comprehensive analysis of GWAS data, involving nearly 1 million cases across ten neurological diseases and ten psychiatric disorders, to compare their common genetic risk and biological underpinnings. Using complementary statistical tools, we demonstrate widespread genetic overlap across the disorders, even in the absence of genetic correlations. This indicates that a large set of common variants impact risk of multiple neurological and psychiatric disorders, but with divergent effect sizes. Furthermore, biological interrogation revealed a range of biological processes associated with neurological diseases, while psychiatric disorders consistently implicated neuronal biology. Altogether, the study indicates that neurological and psychiatric disorders share key etiological aspects, which has important implications for disease classification, precision medicine, and clinical practice.

Association between lipoprotein(a) and ischemic stroke: Fibrinogen as a mediator

BACKGROUND

Previous studies have reported lipoprotein(a) was related to increased risk of ischemic stroke. However, the role of fibrinogen in their associations was not fully elucidated.

AIM

We aimed to investigate the mediating role of fibrinogen in the association between lipoprotein(a) and risk of ischemic stroke.

METHODS

A total of 516 patients with ischemic stroke were matched 1:1 to patients without ischemic stroke for age and gender. Serum lipoprotein(a) and plasma fibrinogen levels were collected on the basis of the results of biochemical tests. Multivariate conditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for lipoprotein(a) levels and ischemic stroke risk. Mediation analysis were further conducted to evaluate the potential mediating role of fibrinogen in the association between lipoprotein(a) and ischemic stroke risk.

RESULTS

The lipoprotein(a) level of subjects with ischemic stroke was significantly higher than that of subjects without ischemic stroke (P < 0.001). Each SD increment of lipoprotein(a) was associated with 27% higher odds (OR 1.27, 95%CI: 1.11, 1.45) increment in ORs of ischemic stroke. Furthermore, mediation analyses indicated that fibrinogen mediated 10.15% of the associations between lipoprotein(a) and ischemic stroke.

CONCLUSIONS

Higher level of lipoprotein(a) was independently associated with increased risk of ischemic stroke and fibrinogen partially mediated the associations of lipoprotein(a) and ischemic stroke risk.

Mendelian Randomization Study Does Not Support a Bidirectional Link between Atherosclerosis and Venous Thromboembolism

AIM

Some observational studies suggested that atherosclerosis increased the risk of venous thromboembolism (VTE), and vice versa. However, the results were conflicting, and the causal relationship is yet to be established. Therefore, we applied Mendelian randomization (MR) analyses to assess the bidirectional causality between coronary heart disease (CHD) and VTE, deep venous thrombosis (DVT), and pulmonary embolism (PE).

METHODS

A total of 184,305 individuals with CHD were included from the CARDIoGRAMplusC4D Consortium. Information on VTE, DVT, and PE were obtained from the FinnGen biobank. Genetic instruments for CHD and VTE were constructed using 37 and 12 single-nucleotide polymorphisms, respectively. Inverse-variance weighted meta-analysis under a random-effect model was used as the preliminary estimate. Five complementary MR methods were also used, including weighted median, MR-Egger, multivariable MR (adjusted for the body mass index), simple mode, and weighted mode methods.

RESULTS

The genetically instrumented VTE (odds ratio [OR]: 1.05; 95% confidence interval [CI]: 1.00-1.11; P=0.06), DVT (OR: 1.03; 95% CI: 0.99-1.08; P=0.19), or PE (OR: 1.07; 95% CI: 0.98-1.16; P=0.11) showed no causal relationships with CHD. There was also no clear evidence showing the causal effects of CHD on VTE (OR: 1.00; 95% CI: 0.82-1.22; P=0.98), DVT (OR: 1.00; 95% CI: 0.79-1.27; P=0.97), or PE (OR: 0.98; 95% CI: 0.82-1.18; P=0.87). No pleiotropic bias was found in the MR analyses. As heterogeneity was significant, a random model was used to minimize the effect of heterogeneity.

CONCLUSIONS

No causal associations existed between CHD and VTE. Arterial and venous thromboses may represent separate entities.

Sex-specific association between microvascular health and coagulation parameters: the Netherlands Epidemiology of Obesity study

BACKGROUND

Microvascular dysfunction is a growing determinant of sex differences in coronary heart disease (CHD). Dysregulation of the coagulation system is involved in CHD pathogenesis and can be induced by endothelial glycocalyx (EG) perturbation. However, little is known about the link between EG function and coagulation parameters in population-based studies on sex specificity.

OBJECTIVES

We sought to examine the sex differences in the relationship between EG function and coagulation parameters in a middle-aged Dutch population.

METHODS

Using baseline measurements of 771 participants from the Netherlands Epidemiology of Obesity study (age, 56 years [IQR, 51-61 years]; 53% women; body mass index, 27.9 kg/m2 [IQR, 25.1-30.9 kg/m2]), associations between glycocalyx-related perfused boundary region (PBR) derived using sidestream dark-field imaging and coagulation parameters (factor [F]VIII/IX/XI; thrombin generation parameters; and fibrinogen) were investigated using linear regression analyses, adjusting for possible confounders (including C-reactive protein, leptin, and glycoprotein acetyls), followed by sex-stratified analyses.

RESULTS

There was a sex difference in the associations between PBR and coagulation parameters. Particularly in women, 1-SD PBR (both total and feed vessel, indicating poorer glycocalyx status) was associated with higher FIX activity ([1.8%; 95% CI, 0.3%-3.3%] and [2.0%; 95% CI, 0.5%-3.4%], respectively) and plasma fibrinogen levels ([5.1 mg/dL; 95% CI, 0.4-9.9 mg/dL] and [5.8 mg/dL; 95% CI, 1.1-10.6 mg/dL], respectively). Furthermore, 1-SD PBRcapillary was associated with higher FVIII activity (3.5%; 95% CI, 0.4%-6.5%) and plasma fibrinogen levels (5.3 mg/dL; 95% CI, 0.6-10.0 mg/dL).

CONCLUSION

We revealed a sex-specific association between microcirculatory health and procoagulant status, which suggests that microvascular health be considered during early development of CHD in women.

Explore the mechanism of ursolic acid acting on atherosclerosis through network pharmacological and bioinformatics methods

To explore the deep mechanisms of ursolic acid (UA) for treating atherosclerosis based on network pharmacology and bioinformatics. UA target genes were derived from traditional Chinese medicine system pharmacology, BATMAN-TCM, and SwissTargetPrediction databases. Atherosclerosis-related genes were derived from genecards, NCBI genes, and OMIM databases. The protein interaction network was constructed through the STRING database, and the hub network was extracted by using the Cytoscape software MCODE app. The enrichment analysis of gene ontology and Kyoto encyclopedia of genes and genomes was performed by the R software clusterProfiler package, and the expression and prognostic value of the hub genes were verified on the data set. Screen the genes for expression and prognosis conclusions, conduct methylation analysis, and ceRNA construction. UA had 145 targets in the treatment of atherosclerosis. The top 7 gene ontology (biological process, molecular function, and cellular component) and pathways related to atherosclerosis were screened out. It is principally involved in biological processes, including response to lipopolysaccharide and regulation of inflammatory response. The main signaling pathways incorporated the TNF signaling pathway and the AGE-RAGE signaling pathway. Androgen receptor (AR) and interleukin-1 beta gene (IL1B) were further screened as core target genes. Methylation analysis demonstrated that the AR methylation level was elevated in the atherosclerotic group. On the contrary, the IL1B methylation level was lower in the atherosclerotic group. The results of the ceRNA analysis indicated that there were 43 targeted miRNAs in AR and 3 miRNAs in IL1B. We speculate that the target genes of UA regulating atherosclerosis are AR and IL1B. The mechanism may be that UA regulates the expression of target genes by regulating the methylation of target genes.

Fibrinogen, Coagulation, and Ageing

The World Health Organization estimates that the world's population over 60 years of age will nearly double in the next 30 years. This change imposes increasing demands on health and social services with increased disease burden in older people, hereafter defined as people aged 60 years or more. An older population will have a greater incidence of cardiovascular disease partly due to higher levels of blood fibrinogen, increased levels of some coagulation factors, and increased platelet activity. These factors lead to a hypercoagulable state which can alter haemostasis, causing an imbalance in appropriate coagulation, which plays a crucial role in the development of cardiovascular diseases. These changes in haemostasis are not only affected by age but also by gender and the effects of hormones, or lack thereof in menopause for older females, ethnicity, other comorbidities, medication interactions, and overall health as we age. Another confounding factor is how we measure fibrinogen and coagulation through laboratory and point-of-care testing and how our decision-making on disease and treatment (including anticoagulation) is managed. It is known throughout life that in normal healthy individuals the levels of fibrinogen and coagulation factors change, however, reference intervals to guide diagnosis and management are based on only two life stages, paediatric, and adult ranges. There are no specific diagnostic guidelines based on reference intervals for an older population. How ageing relates to alterations in haemostasis and the impact of the disease will be discussed in this chapter. Along with the effect of anticoagulation, laboratory testing of fibrinogen and coagulation, future directions, and implications will be presented.

Early myocardial injury and coagulation activation in thoracoscopic left atrial appendage clipping

BACKGROUND

Thoracoscopic left atrial appendage clipping as a new strategy for stroke prevention. This study was established to observe the changes in myocardial injury and coagulation during the perioperative to provide the basis for anticoagulation strategy.

METHODS

Fifty-two patients with nonvalvular atrial fibrillation who completed thoracoscopic left atrial appendage clipping alone and 52 matched controls with thoracoscopic lobectomy were included in the study. The changes in coagulation and myocardial enzyme during the perioperative period were compared by t-test or nonparametric test. Linear correlation analysis was performed on the trend changes of each indicator in the left atrial appendage clipping group.

RESULTS

Compared with the control group, the postoperative cardiac troponin I level in the thoracoscopic left atrial appendage clip group was significantly higher than that before the operation; there was no significant difference in the increase of myoglobin between the two groups. In the coagulation function, there was no significant difference in the increase of fibrinogen between the two groups. Postoperative D-dimer and fibrin degradation products were significantly increased, especially the left atrial appendage clip group was significantly higher than the control group, and even showed a trend of secondary increase. Cardiac troponin I was positively correlated with C-reactive protein, fibrinogen and von Willebrand Factor activity, and the Spearman nonparametric correlation coefficients were 1, 0.829, and 0.829, respectively (all p < .05).

CONCLUSION

Thoracoscopic left atrial appendage closure surgery presents early myocardial injury and activation of coagulation function. The secondary increase of coagulation index needs our attention.

The clinical value of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and D-dimer-to-fibrinogen ratio for predicting pneumonia and poor outcomes in patients with acute intracerebral hemorrhage

Background

This study aimed to investigate the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and D-dimer-to-fibrinogen ratio (DFR) as predictors of pneumonia and poor outcomes in patients with acute intracerebral hemorrhage (ICH).

Methods

We retrospectively examined patients with acute ICH treated in our institution from May 2018 to July 2020. Patient characteristics, laboratory testing data, radiologic imaging data, and 90-day outcomes were recorded and analyzed.

Results

Among the 329 patients included for analysis, 183 (55.6%) developed pneumonia. Systolic blood pressure, initial hematoma volume, D-dimer concentration, NLR, PLR, DFR, and white blood cell, platelet, neutrophil, and lymphocyte counts at admission were significantly higher in patients who developed pneumonia than in those who did not; however, the Glasgow coma scale (GCS) score at admission was significantly lower in pneumonia patients compared with non-pneumonia patients (all P <0.05). Multivariate logistic regression showed that the NLR and PLR were independent predictors of pneumonia, and the NLR and DFR were independent predictors of poor 90-day outcomes (modified Rankin scale score 4–6).

Conclusion

The NLR and PLR were independent predictors of pneumonia and the NLR and DFR were independent predictors of poor 90-day outcomes. The NLR, PLR, and DFR can provide prognostic information about acute ICH patients.

Associations Between 25-Hydroxyvitamin D and Total and γ' Fibrinogen and Plasma Clot Properties and Gene Interactions in a Group of Healthy Black South African Women

The role of 25-hydroxyvitamin D [25(OH)D] in reducing the risk of cardiovascular disease (CVD) has been recognized, but the mechanisms involved are unclear. Researchers have discovered a link between vitamin D and fibrinogen. Until now, data on the relationship between vitamin D and the γ' splice variant of fibrinogen and fibrin clot characteristics remain unexplored. In this study, 25(OH)D, total and γ' fibrinogen, as well as turbidimetrically determined plasma clot properties, were quantified, and fibrinogen and FXIII SNPs were genotyped in 660 Black, apparently healthy South African women. Alarmingly, 16 and 45% of the women presented with deficient and insufficient 25(OH)D, respectively. Total fibrinogen and maximum absorbance (as a measure of clot density) correlated inversely, whereas γ' fibrinogen correlated positively with 25(OH)D. γ' fibrinogen increased whereas maximum absorbance decreased over the deficient, insufficient, and sufficient 25(OH)D categories before and after adjustment for confounders. 25(OH)D modulated the association of the SNPs regarding fibrinogen concentration and clot structure/properties, but did not stand after correction for false discovery rate. Because only weak relationships were detected, the clinical significance of the findings are questionable and remain to be determined. However, we recommend vitamin D fortification and supplementation to reduce the high prevalence of this micronutrient deficiency and possibly to improve fibrinogen and plasma clot structure if the relationships are indeed clinically significant. There is a need for large cohort studies to demonstrate the relationship between vitamin D and cardiovascular and inflammatory risk factors as well as to uncover the molecular mechanisms responsible.

Protective Effects of Diets Rich in Polyphenols in Cigarette Smoke (CS)-Induced Oxidative Damages and Associated Health Implications

Cigarette smoking has been responsible for causing many life-threatening diseases such as pulmonary and cardiovascular diseases as well as lung cancer. One of the prominent health implications of cigarette smoking is the oxidative damage of cellular constituents, including proteins, lipids, and DNA. The oxidative damage is caused by reactive oxygen species (ROS, oxidants) present in the aqueous extract of cigarette smoke (CS). In recent years, there has been considerable interest in the potential health benefits of dietary polyphenols as natural antioxidant molecules. Epidemiological studies strongly suggest that long-term consumption of diets (fruits, vegetables, tea, and coffee) rich in polyphenols offer protective effects against the development of cancer, cardiovascular diseases, diabetes, osteoporosis, and neurodegenerative diseases. For instance, green tea has chemopreventive effects against CI-induced lung cancer. Tea might prevent CS-induced oxidative damages in diseases because tea polyphenols, such as catechin, EGCG, etc., have strong antioxidant properties. Moreover, apple polyphenols, including catechin and quercetin, provide protection against CS-induced acute lung injury such as chronic obstructive pulmonary disease (COPD). In CS-induced health problems, the antioxidant action is often accompanied by the anti-inflammatory effect of polyphenols. In this narrative review, the CS-induced oxidative damages and the associated health implications/pathological conditions (or diseases) and the role of diets rich in polyphenols and/or dietary polyphenolic compounds against various serious/chronic conditions of human health have been delineated.

Variations in Blood Platelet Proteome and Transcriptome Revealed Altered Expression of Transgelin-2 in Acute Coronary Syndrome Patients

Proteomic analyses based on mass spectrometry provide a powerful tool for the simultaneous identification of proteins and their signatures. Disorders detection at the molecular level delivers an immense impact for a better understanding of the pathogenesis and etiology of various diseases. Acute coronary syndrome (ACS) refers to a group of heart diseases generally associated with rupture of an atherosclerotic plaque and partial or complete thrombotic obstruction of the blood flow in the infarct-related coronary artery. The essential role in the pathogenesis of ACS is related to the abnormal, pathological activation of blood platelets. The multifactorial and complex character of ACS indicates the need to explain the molecular mechanisms responsible for thrombosis. In our study, we performed screening and comparative analysis of platelet proteome from ACS patients and healthy donors. Two-dimensional fluorescence difference gel electrophoresis and nanoscale liquid chromatography coupled to tandem mass spectrometry showed altered expressions of six proteins (i.e., vinculin, transgelin-2, fibrinogen β and γ chains, apolipoprotein a1, and tubulin β), with the overlapping increased expression at the mRNA level for transgelin-2. Dysregulation in protein expression identified in our study may be associated with an increased risk of thrombotic events, correlated with a higher aggregability of blood platelets and induced shape change, thus explaining the phenomenon of the hyperreactivity of blood platelets in ACS.

Usefulness of Platelet Distribution Width and Fibrinogen in Predicting In-stent Restenosis With Stable Angina and Type 2 Patients With Diabetes Mellitus

Aim

The purpose of this study was to investigate the predicting value of platelet distribution width (PDW) and fibrinogen for in-stent restenosis (ISR) in patients with stable angina pectoris and type 2 diabetes mellitus (T2DM) after drug-eluting stent (DES) implantation.

Methods

We enrolled 161 patients who were readmitted with recurrent chest pain and successfully reviewed for coronary angiography and were divided into the ISR and non-ISR groups. We compared the levels of PDW and fibrinogen between the two groups. Logistic regression was used for analyzing independent predictors of ISR. The receiver operating characteristic (ROC) curve analysis was used to determine the optimum cutoff points of PDW and fibrinogen to predict ISR. The Kaplan–Meier survival curves for target lesion failure (TLF) by levels of PDW and fibrinogen.

Results

The multivariate logistic regression analysis showed that PDW and fibrinogen were independent predictors of ISR [odds ratio (OR) = 1.209, 95% CI: 1.024–1.427, p = 0.025; OR = 1.006, 95% CI: 1.002–1.011, p = 0.010, respectively]. The ROC analyses showed that PDW ≥ 13.15% and fibrinogen ≥ 333.5 mg/dl were predictive of ISR in patients with stable angina pectoris and T2DM after DES implantation. However, the Kaplan–Meier estimate for TLF showed no statistical significance.

Conclusion

Higher levels of PDW and fibrinogen were associated with the incidence of ISR in patients with stable angina with T2DM after DES implantation, but were not independent predictors of TLF.

Associations between fibrinogen levels and the risk of cardiovascular disease and all-cause death: a cohort study from the Chin-Shan community in Taiwan

OBJECTIVES

Although several studies have investigated the association between fibrinogen level and the risk of cardiovascular disease (CVD), few studies have been conducted in Asia.

SETTING

We conducted a community-based prospective cohort study in the Chin-Shan community, Taiwan.

PARTICIPANTS

A total of 2222 participants (54.6±11.9 years, 53.4% women, and 22.4 years of follow-up) who underwent plasma fibrinogen measurements and were without CVD at baseline were recruited, among which 735 participants with available C reactive protein (CRP) were included in the joint analysis of the association of fibrinogen and CRP levels with the risk of CVD.

PRIMARY AND SECONDARY OUTCOME MEASURES

Fibrinogen and CRP levels were measured by clotting and high-sensitivity immunoturbidimetric assays, respectively. The study outcomes were CVD events and all-cause death. Our definition of CVD included both coronary artery disease (CAD) and stroke cases. Cox proportional hazards regression models were used to estimate the HRs and 95% CIs.

RESULTS

Compared with the lowest quartile, participants with higher fibrinogen levels tended to have a higher risk of CAD (adjusted HR for the highest quartile=1.48 (95% CI 0.90 to 2.44); test for trend p=0.037) regardless of CRP level (adjusted HR=2.12 (95% CI 1.24 to 3.63) and 2.17 (95% CI 1.06 to 4.44) for high fibrinogen/low CRP and high fibrinogen/high CRP, respectively). The association was not observed for stroke (adjusted HR for the highest quartile=0.99 (95% CI 0.62 to 1.60); test for trend p=0.99) and was only observed for all-cause death among participants <65 years of age (adjusted HR for the highest quartile=1.47 (95% CI 1.11 to 1.95); test for trend p=0.004).

CONCLUSIONS

Fibrinogen may be a potential risk factor for CAD but not for stroke. Further studies are necessary to clarify the differences in the role of fibrinogen levels on the risk of CVD between Asian and Western countries.

Biomarkers for Transient Ischemic Attack: A Brief Perspective of Current Reports and Future Horizons

Cerebrovascular disease is the leading cause of long-term disability in the world and the third-leading cause of death in the United States. The early diagnosis of transient ischemic attack (TIA) is of great importance for reducing the mortality and morbidity of cerebrovascular diseases. Patients with TIA have a high risk of early subsequent ischemic stroke and the development of permanent nervous system lesions. The diagnosis of TIA remains a clinical diagnosis that highly relies on the patient's medical history assessment. There is a growing list of biomarkers associated with different components of the ischemic cascade in the brain. In this review, we take a closer look at the biomarkers of TIA and their validity with a focus on the more clinically important ones using recent evidence of their reliability for practical usage.

Prognostic significance of international normalised ratio and prothrombin time in Chinese acute ischaemic stroke patients

BACKGROUND

We investigated the association between international normalised ratio (INR) and prothrombin time (PT) levels on hospital admission and in-hospital outcomes in acute ischaemic stroke (AIS) patients.

METHODS

A total of 3175 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included. We divided patients into four groups according to their level of admission INR: (<0.92), Q2 (0.92-0.98), Q3 (0.98-1.04) and Q4 (≥1.04) and PT. Logistic regression models were used to estimate the effect of INR and PT on death or major disability (modified Rankin Scale score (mRS)>3), death and major disability (mRS scores 4-5) separately on discharge in AIS patients.

RESULTS

Having an INR level in the highest quartile (Q4) was associated with an increased risk of death or major disability (OR 1.69; 95% CI 1.23 to 2.31; P-trend=0.001), death (OR, 2.64; 95% CI 1.12 to 6.19; P-trend=0.002) and major disability on discharge (OR, 1.56; 95% CI 1.13 to 2.15; P-trend=0.008) in comparison to Q1 after adjusting for potential covariates. Moreover, in multivariable logistic regression models, having a PT level in the highest quartile also significantly increased the risk of death (OR, 2.38; 95% CI 1.06 to 5.32; P-trend=0.006) but not death or major disability (P-trend=0.240), major disability (P-trend=0.606) on discharge.

CONCLUSIONS

High INR at admission was independently associated with death or major disability, death and major disability at hospital discharge in AIS patients and increased PT was also associated with death at hospital discharge.

Fibrin-mediated growth restriction of early-stage human trophoblasts is switched to growth promotion through fibrinolysis

STUDY QUESTION

Does fibrin promote trophoblast growth in human and mouse blastocysts during early embryo implantation?

SUMMARY ANSWER

Mouse blastocysts were unaffected by fibrin; however, human blastocysts were significantly suppressed by fibrin in trophoblast growth and then switched to growth promotion through increased fibrinolysis with urokinase-type plasminogen activator (uPA) activity.

WHAT IS KNOWN ALREADY

Fibrin(ogen) plays an important role in various physiological processes and is also critical for maintaining feto-maternal attachment during pregnancy. The addition of fibrin to embryo transfer media has been used to increase implantation rates in human ART; however, its mechanism of action' in vitro has not yet been characterized.

STUDY DESIGN, SIZE, DURATION

Vitrified mouse and human blastocysts were warmed and individually cultured in vitro for up to 120 and 168 h, respectively, on a fibrin substrate. Blastocysts were cultured at 37°C in 6% CO2, 5% O2 and 89% N2. Blastocyst development and related fibrinolytic factors were analyzed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

ICR strain mouse embryos were purchased from a commercial supplier. Human blastocysts were donated with informed consent from two fertility centers. Mouse and human blastocysts cultured on fibrin-coated plates were compared to those on non-coated and collagen-coated plates in vitro. Trophoblast growth and fibrin degradation were assessed based on the cell area and fibrin-free area, respectively. Fibrinolytic factors were detected in supernatants using plasminogen-casein zymography. The fibrinolytic activity of blastocysts was investigated using a selective uPA inhibitor, exogenous uPA, plasminogen activator inhibitor-1 (PAI-1) inhibitor and fibrin degradation products (FDPs). Fibrinolysis-related mRNA expression level was detected using quantitative real-time PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Fibrin did not affect the developmental speed or morphology of mouse blastocysts, and a large fibrin-degrading region was observed in the attachment stage. In contrast, fibrin significantly suppressed the outgrowth of trophoblasts in human blastocysts, and trophoblasts grew after the appearance of small fibrin-degrading regions. uPA was identified as a fibrinolytic factor in the conditioned medium, and uPA activity was significantly weaker in human blastocysts than in mouse blastocysts. The inhibition of uPA significantly reduced the outgrowth of trophoblasts in mouse and human blastocysts. Human blastocysts expressed PLAU (uPA), PLAUR (uPA receptor), SERPINE1 (PAI-1) and SERPINB2 (PAI-2), whereas mouse blastocysts were limited to Plau, Plaur and Serpine1. In a subsequent experiment on human blastocysts, the addition of exogenous uPA and the PAI-1 inhibitor promoted trophoblast growth in the presence of fibrin, as did the addition of FDPs.

LIMITATIONS, REASONS FOR CAUTION

This model excludes maternal factors and may not be fully reproduced in vivo. Donated human embryos are surplus embryos that may inherently exhibit reduced embryonic development. In addition, donated ART-derived embryos may exhibit weak uPA activity, because women with sufficient uPA-active embryos may not originally require ART. The present study used orthodox culture methods, and results may change with the application of recently developed protocols for culture blastocysts beyond the implantation stage.

WIDER IMPLICATIONS OF THE FINDINGS

The present results suggest that the distinct features of trophoblast outgrowth in human blastocysts observed in the presence of fibrin are regulated by a phenotypic conversion induced by contact with fibrin and FDPs. Mouse embryos did not exhibit the human phenomenon, indicating that the present results may be limited to humans.

STUDY FUNDING/COMPETING INTEREST(S)

The present study was supported by the Department of Obstetrics and Gynecology at the Hamamatsu University School of Medicine and Kishokai Medical Corporation. None of the authors have any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Extracellular Vesicles in Premature Aging and Diseases in Adulthood Due to Developmental Exposures

The developmental origins of health and disease (DOHaD) is a paradigm that links prenatal and early life exposures that occur during crucial periods of development to health outcome and risk of disease later in life. Maternal exposures to stress, some psychoactive drugs and alcohol, and environmental chemicals, among others, may result in functional changes in developing fetal tissues, creating a predisposition for disease in the individual as they age. Extracellular vesicles (EVs) may be mediators of both the immediate effects of exposure during development and early childhood as well as the long-term consequences of exposure that lead to increased risk and disease severity later in life. Given the prevalence of diseases with developmental origins, such as cardiovascular disease, neurodegenerative disorders, osteoporosis, metabolic dysfunction, and cancer, it is important to identify persistent mediators of disease risk. In this review, we take this approach, viewing diseases typically associated with aging in light of early life exposures and discuss the potential role of EVs as mediators of lasting consequences.

Quantitative analysis of clot density, fibrin fiber radius, and protofibril packing in acute phase myocardial infarction

INTRODUCTION

Coronary artery disease is associated with impaired clot structure. The aim of this study was to investigate acute phase myocardial infarction (AMI) and provide detailed quantitative analysis of clot ultrastructure.

MATERIALS AND METHODS

Clot formation and breakdown, pore size, fiber density, fiber radius and protofibril packing were investigated in plasma clots from AMI patients. These data were compared to those from healthy controls.

RESULTS

Analysis on clot formation using turbidity showed increased lag time, suggesting changes in protofibril packing and increased fiber size for AMI patients compared to healthy controls. Additionally, increased average rate of clotting and decreased time to maximum absorbance in AMI patients suggest that clots formed more quickly. Moreover, we observed increased time from max OD to max rate of lysis. Increased fibrinogen and decreased plasminogen in AMI patients were accounted for in represented significant differences. AMI samples showed increased time to 25% and 50% lysis, but no change in 75% lysis, representative of delayed lysis onset, but expediated lysis once initiated. These data suggest that AMI patients formed less porous clots made from more densely packed fibers with decreased numbers of protofibrils, which was confirmed using decreased permeation and increased fiber density, and decreased turbidimetry.

CONCLUSIONS

AMI plasma formed clots that were denser, less permeable, and lysed more slowly than healthy controls. These findings were confirmed by detailed analysis of clot ultrastructure, fiber size, and protofibril packing. Dense clot structures that are resistant to lysis may contribute to a prothrombotic milieu in AMI.

Fibrinogen-to-albumin ratio may be a predictor for ascending aortic aneurysm

OBJECTIVE

The predictive value of the fibrinogen-to-albumin ratio has been evidenced in coronary artery disease. Available data demonstrated that inflammation and oxidative stress are the relevant mechanisms of ascending aortic aneurysm formation and dilatation. The fibrinogen-to-albumin ratio reflects oxidative stress and inflammation. This study investigated the correlation between fibrinogen-to-albumin ratio and ascending aortic aneurysm.

METHODS

A total of 250 consecutive patients with ascending aortic aneurysm and 250 consecutive patients with normal ascending aortic diameter were included in the study using comprehensive transthoracic echocardiography. All data and fibrinogen-to-albumin ratio were compared between two groups.

RESULTS

The fibrinogen-to-albumin ratio levels were significantly higher in ascending aortic aneurysm group compared with normal ascending aortic diameter group (p<0.001). Also, there was significantly positive correlation between the diameter of the ascending aorta and the fibrinogen-to-albumin ratio (p<0.001).

CONCLUSION

Fibrinogen-to-albumin ratio is associated with ascending aortic aneurysm and may serve as blood marker for identifying high-risk patients.

Smoking Cessation after Diagnosis of New-Onset Atrial Fibrillation and the Risk of Stroke and Death

Limited data are available regarding the impact of smoking cessation after atrial fibrillation (AF) diagnosis on clinical outcomes. Using the Korean National Health Insurance Service database, we included patients newly diagnosed with AF and categorized them into four groups as follows: (i) never smokers, (ii) ex-smokers, (iii) smoking cessation after AF diagnosis ("quitters"), and (iv) current smokers. The primary outcomes were incident ischemic stroke and all-cause death during follow-up. Fatal ischemic stroke and death from cerebrovascular events were evaluated as secondary outcomes. Among 97,637 patients (mean age, 61 years; mean CHA₂DS₂-VASc score, 2.3), 6.9% stopped smoking after AF diagnosis. The mean follow-up duration was 3.2 ± 2.0 years. After multivariable adjustment, quitters had lower risks of ischemic stroke (hazard ratio (HR), 0.702; 95% confidence interval (CI), 0.595-0.827) and all-cause death (HR, 0.842; 95% CI, 0.748-0.948) than current smokers. Quitters after AF diagnosis were associated with lower risks of fatal ischemic stroke (HR, 0.454; 95% CI, 0.287-0.718) and death from cerebrovascular events (HR, 0.664; 95% CI, 0.465-0.949) compared with current smokers. Quitting smoking may reduce the risk of ischemic stroke, the severity of ischemic stroke, and the incidence of cerebrovascular events in patients with new-onset AF.

Translocator Protein Modulation by 4'-Chlorodiazepam and NO Synthase Inhibition Affect Cardiac Oxidative Stress, Cardiometabolic and Inflammatory Markers in Isoprenaline-Induced Rat Myocardial Infarction

The possible cardioprotective effects of translocator protein (TSPO) modulation with its ligand 4'-Chlorodiazepam (4'-ClDzp) in isoprenaline (ISO)-induced rat myocardial infarction (MI) were evaluated, alone or in the presence of L-NAME. Wistar albino male rats (b.w. 200-250 g, age 6-8 weeks) were divided into 4 groups (10 per group, total number N = 40), and certain substances were applied: 1. ISO 85 mg/kg b.w. (twice), 2. ISO 85 mg/kg b.w. (twice) + L-NAME 50 mg/kg b.w., 3. ISO 85 mg/kg b.w. (twice) + 4'-ClDzp 0.5 mg/kg b.w., 4. ISO 85 mg/kg b.w. (twice) + 4'-ClDzp 0.5 mg/kg b.w. + L-NAME 50 mg/kg b.w. Blood and cardiac tissue were sampled for myocardial injury and other biochemical markers, cardiac oxidative stress, and for histopathological evaluation. The reduction of serum levels of high-sensitive cardiac troponin T hs cTnT and tumor necrosis factor alpha (TNF-α), then significantly decreased levels of serum homocysteine Hcy, urea, and creatinine, and decreased levels of myocardial injury enzymes activities superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as lower grades of cardiac ischemic changes were demonstrated in ISO-induced MI treated with 4'-ClDzp. It has been detected that co-treatment with 4'-ClDzp + L-NAME changed the number of registered parameters in comparison to 4'-ClDzp group, indicating that NO (nitric oxide) should be important in the effects of 4'-ClDzp.

Fibrinogen-to-albumin ratio predicts long-term outcomes for patients with ST-elevation myocardial infarction and multivessel disease: A prospective observational cohort study

The fibrinogen-to-albumin ratio index (FAR) is a valuable tool reflecting the systemic inflammation level and associated with the severity of coronary artery disease. However, the utility of the FAR in predicting the long-term prognosis of patients with ST-elevation myocardial infarction (STEMI) and multivessel disease has remained to be determined. A total of 424 patients diagnosed with STEMI and multivessel disease were recruited for the present study. They were given emergent percutaneous coronary intervention treatment and then completed a follow-up for primary (all-cause mortality) and secondary endpoints (major adverse cardiac events, including MI, stroke, emergent revascularization and rehospitalization due to heart failure). The association between FAR and the Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score was investigated, while receiver operating characteristic curve analysis was adopted to assess the ability of the FAR to predict long-term outcomes. The long-term survival of high and low FAR groups was compared by drawing Kaplan-Meier survival curves. Multivariate Cox regression analysis was adopted to evaluate the risk factors of primary and secondary endpoints. The FAR was revealed to have a linear correlation with the SYNTAX score (y=0.022x+17.737; P=0.015). Furthermore, the FAR was a significant predictor of all-cause death with a cut-off value of 128.4 (area under the curve, 0.832; P<0.001). A significant difference was determined between the high FAR group and the low FAR group in terms of the proportion of patients with the primary endpoint (P<0.001) and secondary endpoint (P=0.001). It was demonstrated that the FAR was an independent risk factor for all-cause death of patients with STEMI and multivessel disease (hazard ratio, 1.029; 95% CI: 1.020-1.037; P<0.001). In summary, the FAR is a valuable biomarker associated with STEMI and may be useful in the prediction of the long-term prognosis of patients with STEMI and multivessel disease.

Thrombin-Fibrin(ogen) Interactions, Host Defense and Risk of Thrombosis

Fibrinogen is a well-known risk factor for arterial and venous thrombosis. Its function is not restricted to clot formation, however, as it partakes in a complex interplay between thrombin, soluble plasma fibrinogen, and deposited fibrin matrices. Fibrinogen, like thrombin, participates predominantly in hemostasis to maintain vascular integrity, but executes some important pleiotropic effects: firstly, as observed in thrombin generation experiments, fibrin removes thrombin from free solution by adsorption. The adsorbed thrombin is protected from antithrombins, notably α2-macroglobulin, and remains physiologically active as it can activate factors V, VIII, and platelets. Secondly, immobilized fibrinogen or fibrin matrices activate monocytes/macrophages and neutrophils via Mac-1 interactions. Immobilized fibrin(ogen) thereby elicits a pro-inflammatory response with a reciprocal stimulating effect of the immune system on coagulation. In contrast, soluble fibrinogen prohibits recruitment of these immune cells. Thus, while fibrin matrices elicit a procoagulant response, both directly by protecting thrombin and indirectly through the immune system, high soluble fibrinogen levels might protect patients due to its immune diminutive function. The in vivo influence of the 'protective' plasma fibrinogen versus the 'pro-thrombotic' fibrin matrices on thrombosis should be explored in future research.

Safety and Impact of Low-dose Methotrexate on Endothelial Function and Inflammation in Individuals With Treated Human Immunodeficiency Virus: AIDS Clinical Trials Group Study A5314

BACKGROUND

Chronic inflammation in treated HIV infection is associated with mortality and atherosclerotic cardiovascular disease (ASCVD). We evaluated the safety and potential efficacy of low-dose methotrexate (LDMTX) in treated HIV.

METHODS

This was a phase 2 randomized, double-blind, multicenter trial in adults ≥40 years old with treated HIV, with CD4+ T-cell count ≥400 cells/μL and with/at increased risk for ASCVD. Participants received LDMTX (5-15 mg/week) or placebo (plus folic acid) for 24 weeks and were followed for an additional 12 weeks. Primary endpoints were safety and brachial artery flow-mediated dilation (FMD).

RESULTS

The 176 participants (90% male) had a median (Q1, Q3) age of 54 (49, 59) years. LDMTX was associated with decreases in CD4+ T cells at week 24 and CD8+ T cells at weeks 8, 12, and 24. Eleven participants (12.8%) experienced safety events in the LDMTX group vs 5 (5.6%) in placebo (Δ = 7.2%, upper 1-sided 90% CI, 13.4%; Pnoninferiority = .037). Week 24 change in FMD was 0.47% with LDMTX and 0.09% with placebo (P = .55). No inflammatory markers changed differentially with LDMTX compared to placebo.

CONCLUSIONS

Adults with HIV and increased ASCVD risk treated with LDMTX had more safety events than with placebo, but the prespecified noninferiority margin of 15% was not exceeded. LDMTX had no significant effect on endothelial function or inflammatory biomarkers but was associated with a significant decrease in CD8+ T cells. The balance of risks and potential benefits of LDMTX in this population will require additional investigation.

CLINICAL TRIALS REGISTRATION

NCT01949116.

The Potential Value of D-Dimer to Fibrinogen Ratio in Diagnosis of Acute Ischemic Stroke

INTRODUCTION AND OBJECTIVE

At present, there is no hematology marker with high specificity to the diagnosis and differential diagnosis of acute ischemic stroke (AIS). How to use the existing test items to improve the diagnosis efficiency worthy of discussion. D-Dimer (DD) and fibrinogen (FIB) were the common indicators in thrombotic diseases, but D-dimer to fibrinogen ratio (D/F) in AIS has not been used in clinical practice. In this work, we focus on the evaluation of D/F.

METHODS

90 AIS patients were selected as the observation group and 65 other patients without coagulation function disorder as the control group. Meanwhile, a total of 33 patients with other diseases with impaired consciousness in the same period were collected. Based on the AIS patients with or without consciousness disorder divided it into consciousness disorder group and unconsciousness disorder group. Then based on the patients with or without consciousness disorder divided it into other diseases with unconsciousness disorder group and Other diseases with lacunar cerebral infarction (LCI)and disturbance of consciousness group. then compare the differences of plasma DD, FIB and D/F between groups.

RESULTS

All plasma DD, FIB and D/F ratio in AIS patients were significantly higher than in other disease group (P = 0.000, P = 0.001, P = 0.000), but DD, D/F in disorders of consciousness group was significantly higher than in unconsciousness disorders group (P = 0.007, P = 0.005). The DD of the AIS with consciousness disorder group were significantly higher than that of the other disease with consciousness disorder group (P = 0.042), and the DD, D/F ratio of Other diseases with lacunar cerebral infarction and disturbance of consciousness group were significantly higher than one(P = 0.000, P = 0.003). All others are undifferentiated.

CONCLUSIONS

When DD, D/F ratio is high, other diseases caused by consciousness disorders are likely to be combined with infarcts, which can be used for the diagnosis and differential diagnosis of patients with different types of consciousness disorders, especially hospitalized patients.

Relationship between fibrinogen level and its regulatory gene with Alzheimer's disease and vascular dementia

Objective

Methods

Results

Conclusions

Elevated Llpoprotein(A) and Fibrinogen Serum Levels Increase the Cardiovascular Risk in Continuous Ambulatory Peritoneal Dialysis Patients

Objective

To analyze the relationship between lipoprotein(a) [Lp(a)] and fibrinogen as potential cardiovascular risk factors in patients on continuous ambulatory peritoneal dialysis (CAPD).

Patients

A total of 47 uremic patients receiving CAPD, 21 with coronary artery disease (CAD), 26 without CAD.

Measurements

Lp(a) levels were determined by an immunoradiometric assay. Since Lp(a) serum concentrations vary depending on the size, apoprotein(a) [apo(a)] isoforms were determined (Westernblot). Fibrinogen was quantified according to Clauss.

Results

The mean Lp(a) serum concentration was 43 ± 5 mg/dL (SEM) (median 33 mg/dL) in CAPD patients and 21 ± 2 mg/dL (8 mg/dL) in controls (p < 0.01). Patients with low molecular weight apo(a) isoforms exhibited substantially elevated Lp(a) levels when compared with patients with high molecular isoforms (p < 0.01). In addition, we found elevated fibrinogen levels in the CAPD patients (538 ± 61 mg/dL) compared with healthy controls (288 ± 46 mg/dL). Twenty-one CAPD patients (45%) were suffering from CAD. Patients with CAD had higher Lp(a) levels (54 ± 5 mg/dL vs 34 ± 4 mg/dL) as well as higher fibrinogen concentrations (628 ± 59 mg/dL vs 459 ± 46 mg/dL). Furthermore, a positive correlation between the fibrinogen levels and the Lp(a) serum concentration was observed (r = 0.45, p = 0.01).

Conclusion

We suggest that elevated Lp(a) levels are influenced by the allelic variation of the apo(a) isoform. In addition to the typical dyslipidemia found in CAPD patients, high levels of Lp(a) and fibrinogen may contribute to the elevated risk of coronary artery disease and other cardiovascular complications.

Fibrinogen and Fibrinolytic Activity in Capd Patients with Atherosclerosis and Its Correlation with Serum Albumin

Objective

It has been suggested that hypoalbuminemia in dialysis patients leads to a hypercoagulable state, however, the relationship between serum albumin and fibrinogen or fibrinolytic activity has not been well-documented. The aim of this study was to investigate the changes of fibrinogen, tissue plasminogen activator (tPA), plasminogen activator inhibitor type-1 (PAI-1), and lipid levels in continuous ambulatory peritoneal dialysis (CAPD) patients with atherosclerosis, and the relationship between those factors and serum albumin.

Design

A cross-sectional study.

Setting

A university hospital.

Patients

Twenty CAPD patients with atherosclerosis, 49 CAPD patients without atherosclerosis, and 33 normal controls were included. Presence of atherosclerosis was determined by positive results in a stress thallium singlephoton emission computed tomography or an ankle brachial index less than 0.9. Coronary angiography and/ or Doppler ultrasound of extremities were followed for the patients with positive results to confirm atherosclerotic cardiovascular disease.

Main outcome measures

tPA and PAI-1 levels were determined with ELISA method, and fibrinogen with thrombin time method. Serum albumin and lipids were also measured.

Results

Serum albumin and HDL -cholesterol levels were significantly lower, and the ratio of total cholesterol/ HDL was significantly higher, in CAPD patients than in normal controls. CAPD patients with atherosclerosis had significantly higher fibrinogen, tPA, and PAI-levels than other groups. tPA was an independent predictor of atherosclerotic vascular disease in CAPD patients in stepwise logistic regression analysis. Serum albumin level was inversely correlated with fibrinogen (r = -0.28; p < 0.05) in CAPD patients, but not with tPA or PAI-1 levels. PAI-1 level was correlated with tPA (r = 0.37; p < 0.01) and triglycerides (r = 0.32; p < 0.05).

Conclusions

Association of high levels of fibrinogen and PAI-1 with lipid disorders may be of importance in the development of atherosclerosis in CAPD patients. Hypoalbuminemia may contribute to atherosclerosis via increased synthesis of fibrinogen.

Structure, mechanical properties, and modeling of cyclically compressed pulmonary emboli

Pulmonary embolism occurs when blood flow to a part of the lungs is blocked by a venous thrombus that has traveled from the lower limbs. Little is known about the mechanical behavior of emboli under compressive forces from the surrounding musculature and blood pressure. We measured the stress-strain responses of human pulmonary emboli under cyclic compression, and showed that emboli exhibit a hysteretic stress-strain curve. The fibrin fibers and red blood cells (RBCs) are damaged during the compression process, causing irreversible changes in the structure of the emboli. We showed using electron and confocal microscopy that bundling of fibrin fibers occurs due to compression, and damage is accumulated as more cycles are applied. The stress-strain curves depend on embolus structure, such that variations in composition give quantitatively different responses. Emboli with a high fibrin component demonstrate higher normal stress compared to emboli that have a high RBC component. We compared the compression response of emboli to that of whole blood clots containing various volume fractions of RBCs, and found that RBCs rupture at a certain critical stress. We describe the hysteretic response characteristic of foams, using a model of phase transitions in which the compressed foam is segregated into coexisting rarefied and densified phases whose fractions change during compression. Our model takes account of the rupture of RBCs in the compressed emboli and stresses due to fluid flow through their small pores. Our results can help in classifying emboli as rich in fibrin or rich in red blood cells, and can help in understanding what responses to expect when stresses are applied to thrombi in vivo.

Fibrin(ogen) in human disease: both friend and foe

Fibrinogen is an abundant protein synthesized in the liver, present in human blood plasma at concentrations ranging from 1.5-4 g/L in healthy individuals with a normal half-life of 3-5 days. With fibrin, produced by thrombin-mediated cleavage, fibrinogen plays important roles in many physiological processes. Indeed, the formation of a stable blood clot, containing polymerized and cross-linked fibrin, is crucial to prevent blood loss and drive wound healing upon vascular injury. A balance between clotting, notably the conversion of fibrinogen to fibrin, and fibrinolysis, the proteolytic degradation of the fibrin mesh, is essential. Disruption of this equilibrium can cause disease in distinct manners. While some pathological conditions are the consequence of altered levels of fibrinogen, others are related to structural properties of the molecule. The source of fibrinogen expression and the localization of fibrin(ogen) protein also have clinical implications. Low levels of fibrinogen expression have been detected in extra-hepatic tissues, including carcinomas, potentially contributing to disease. Fibrin(ogen) deposits at aberrant sites including the central nervous system or kidney, can also be pathological. In this review, we discuss disorders in which fibrinogen and fibrin are implicated, highlighting mechanisms that may contribute to disease.

Proteomic and Metabolomic Profiling Identify Plasma Biomarkers for Exposure to Ultra-low Levels of Carfentanil

Despite the recent epidemic of fentanyl abuse, there are few validated assays capable of rapidly detecting these compounds. In order to improve the ability to detect carfentanil at physiologically relevant concentrations, we developed a systems biology approach to discover host-based markers which are specifically amplified upon exposure in a rabbit model. For this work, two "omics" pipelines utilizing mass spectrometry were developed and leveraged. First, a proteomics pipeline was developed to interrogate the blood plasma for protein-based biomarkers. Due to the incredible dynamic range of the plasma protein content, a multi-dimensional fractionation technique was used to partition and more accurately investigate the circulating plasma proteome. Isobaric tandem mass tags were integrated into the workflow to make quantitative assessments across all animals for an extended time course post-exposure. In addition to the proteomics efforts, blood plasma was also processed through an untargeted metabolomics pipeline. This approach allows for the identification of >800 small molecule features. By processing and analyzing data sets in parallel, we were able to identify a unique fingerprint of protein and metabolite perturbations that manifest following exposure to carfentanil.

Cardioprotective effects of (E)-4-hydroxy-N'-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene)benzohydrazide: a newly synthesized coumarin hydrazone against isoproterenol-induced myocardial infarction in a rat model

The current study was carried out to evaluate the effect of pretreatment and co-treatment with a newly synthesized coumarin hydrazone, (E)-4-hydroxy-N'-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene)benzohydrazide (hereinafter EK6), against isoproterenol-induced myocardial infarction in rats. Changes in biochemistry, cardiac biomarkers, electrocardiography, and histopathology after treatment with EK6 or acenocoumarol (Sintrom) were studied. Animals were randomly divided into 4 groups: vehicle control (C), isoproterenol + Sintrom (ISO + Sin), isoproterenol + EK6 (ISO + EK6), and isoproterenol (ISO). Myocardial infarction was induced by subcutaneous ISO administration at a dose of 85 mg·kg^-1·day^-1 with a drug-free interval of 24 h on days 6 and 7. Treatment with ISO led to significant elevation (p < 0.05) in serum levels of cardiac injury biomarkers, namely cardiac troponin-T, lactate dehydrogenase, creatine kinase-MB, alanine aminotransferase, and aspartate aminotransferase compared with levels in the vehicle control. A change in the lipid profile was also observed as a significant increase in total cholesterol and triglycerides. Furthermore, ISO caused significant alterations in the electrocardiogram pattern, including significant ST-segment elevation, significant decreased R wave amplitude, and significant increase in heart rate (16%) as well as marked changes in the histopathology of the heart tissue. Pretreatment and co-treatment with newly synthesized coumarin hydrazone restored all ISO-induced biochemical, lipid, cardiac, and histopathological changes in rats with myocardial infarction.

Prognostic value of fibrinogen-to-albumin ratio in predicting 1-year clinical progression in patients with non-ST elevation acute coronary syndrome undergoing percutaneous coronary intervention

Previous studies have indicated that fibrinogen and low serum albumin levels are associated with poor cardiovascular outcomes. The objective of the present study was to examine whether the fibrinogen-to-albumin ratio (FAR) was able to predict the 1-year prognosis of patients with non-ST elevation acute coronary syndrome (NSTE-ACS) following percutaneous coronary intervention (PCI). A total of 1,352 patients with NSTE-ACS undergoing PCI were included in this prospective study and were divided into a low-FAR group (FAR ≤8.713, n=901) and a high-FAR group (FAR>8.713, n=451). FAR was defined as the concentration ratio of fibrinogen (mg/dl) to albumin (mg/dl) multiplied by 100. The endpoint was the incidence of major adverse cardiovascular events (MACEs), including all-cause mortality, cardiac mortality, non-fatal myocardial reinfarction and unscheduled repeat revascularisation. The predictive performance was validated by receiver-operator characteristic (ROC) curve analysis. A total of 127 MACEs were noted during the 1-year follow-up period. Multivariate Cox analysis suggested that a high FAR was an independent predictor of all-cause mortality (hazard ratio=2.223, 95% confidence interval: 1.002-4.931, P=0.049). Regarding the predictor of MACEs, the FAR exhibited an area under the ROC curve of 0.676 with a sensitivity of 0.630 and a specificity of 0.726. The cut-off value was 9.114. The FAR was an independent prognostic factor in NSTE-ACS. The present results suggest that the FAR may serve as a potential prognostic indicator for patients with NSTE-ACS undergoing PCI (approval no. NCT02667548; January 29, 2016; Shengjing Hospital of China Medical University).

Polymorphisms -455G/A and -148C/T and Fibrinogen Plasmatic Level as Risk Markers of Coronary Disease and Major Adverse Cardiovascular Events

Some polymorphisms in genes codifying for fibrinogen have been correlated with plasma levels of this protein, and several studies reported their associations with acute cardiovascular events. In the present study, 118 subjects with unstable and stable coronary diseases were enrolled to determinate the associations among fibrinogen gene polymorphisms, plasma fibrinogen levels, and major cardiovascular adverse events in a sample of southwestern Mexico. The groups, including 81 control subjects, were matched for age, sex, body mass index, and sedentarism. Plasma fibrinogen levels and the polymorphisms 455G/A, -148C/T, +1689T/G, and Bcl I of the gene of fibrinogen were compared in all groups. Plasma fibrinogen levels (>465 mg/dl) were significant in patients with coronary disease. Fibrinogen plasma values > 450 mg/dl were associated with cardiovascular mortality during the follow-up analysis of the unstable coronary disease group (p = 0.04). The allelic loads of -455A and -148T were associated with plasma fibrinogen levels > 450 mg/dl (p < 0.003 and p = 0.03, respectively) and with coronary disease (p = 0.016 and p < 0.006, respectively). The follow-up of posterior events after an acute coronary event showed that the genetic load of the -148T allele was associated with major adverse cardiovascular events (RR = 1.8, 95%CI = 1.01‐3.35, p = 0.04). Fibrinogen plasmatic levels > 450 mg/dl and the fibrinogen polymorphisms -455G/A and 148C/T had association with MACE and coronary disease. This study suggests that these gene polymorphisms are associated with cardiovascular risk.

Correlation Between Hemorheologic Parameters and Carotid Atherosclerosis in Stroke

An evaluation of the hemorheologic parameters and an ultrasonographic study of the extracranial carotid tract were performed on 48 patients, age range: sixty to seventy-five years, affected by acute stroke, 23 of whom had hypertension, while 27 were smokers. None of them was suffering from hyperli pidemia, diabetes mellitus, or symptomatic coronary heart or peripheral artery disease.

The echotomographic analysis, using B-mode real-time echotomography re vealed atherosclerotic lesions in 26 patients. The hemorheologic pattern (hema tocrit, fibrinogen, whole blood filterability, whole blood and plasma viscosity) was determined in all the patients three months after the clinical event.

Statistical analysis of the results indicates a possible link between athero sclerotic lesions of the extracranial carotid tract and age, fibrinogen levels, and whole blood filterability.