Hydrogel microsphere stem cell encapsulation enhances cardiomyocyte differentiation and functionality in scalable suspension system.

A reliable suspension-based platform for scaling engineered cardiac tissue (ECT) production from human induced pluripotent stem cells (hiPSCs) is crucial for regenerative therapies. Here, we compared the production and functionality of ECTs formed using our scaffold-based, engineered tissue microsphere differentiation approach with those formed using the prevalent scaffold-free aggregate platform. We utilized a microfluidic system for the rapid (1 million cells/min), high density (30, 40, 60 million cells/ml) encapsulation of hiPSCs within PEG-fibrinogen hydrogel microspheres. HiPSC-laden microspheres and aggregates underwent suspension-based cardiac differentiation in chemically defined media. In comparison to aggregates, microspheres maintained consistent size and shape initially, over time, and within and between batches. Initial size and shape coefficients of variation for microspheres were eight and three times lower, respectively, compared to aggregates. On day 10, microsphere cardiomyocyte (CM) content was 27 % higher and the number of CMs per initial hiPSC was 250 % higher than in aggregates. Contraction and relaxation velocities of microspheres were four and nine times higher than those of aggregates, respectively. Microsphere contractile functionality also improved with culture time, whereas aggregate functionality remained unchanged. Additionally, microspheres displayed improved ß-adrenergic signaling responsiveness and uniform calcium transient propagation. Transcriptomic analysis revealed that while both microspheres and aggregates demonstrated similar gene regulation patterns associated with cardiomyocyte differentiation, heart development, cardiac muscle contraction, and sarcomere organization, the microspheres exhibited more pronounced transcriptional changes over time. Taken together, these results highlight the capability of the microsphere platform for scaling up biomanufacturing of ECTs in a suspension-based culture platform.

Fibrinogen αC-region acts as a functional safety latch: implications for a fibrin biomechanical behaviour model.

Fibrin has unique biomechanical properties which are essential for its role as a scaffold for blood clots. Fibrin is highly extensible and demonstrates significant strain stiffening behaviour, which is essential for stress-distribution in the network. Yet the exact structures of fibrin at the sub-fibre level that contribute to its unique biomechanical characteristic are unknown. Here we show how truncations of the fibrinogen αC-region impact the biomechanical properties of fibrin fibres. Surprisingly, absence of the complete αC-region did not influence the low strain modulus of fibrin fibres but led to premature fibre rupture and decreased extensibility. Intermediate effects were observed with partial deletion of the αC-region, reflected by intermediate rupture stress and toughness. However, overall strain-stiffening behaviour remained even in absence of the αC-region, indicating that strain stiffening is not due to stress being transferred from the αC-region to the protofibril backbone. Upon stress-relaxation, decay constants and their relative contribution to the total relaxation remained similar at all strains, showing that a distinct relaxation process is present until fibre rupture. However, relative contribution of fast relaxation was maximal only in crosslinked fibres if the flexible αC-connector was present. These data show that the αC-region is not the main load-bearing structure within fibrin fibres and point to a critical role for the protofibril backbone instead. We present a revised structural model based on protofibril branching that fully explains the unique biomechanical behaviour of fibrin fibres, while the αC-region primarily acts as a safety latch at the highest of strains. STATEMENT OF SIGNIFICANCE: The findings presented in this paper reveal critically important details about how the molecular structure of fibrin contributes to its unique mechanical properties which are essential to fulfil its function as the scaffold of blood clots. In this work we used engineered proteins with alterations in an important but highly disordered area of the molecule called αC-region and we provide direct evidence for the first time for how the absence of either the globular αC-domain, or the complete αC-region impacts the mechanical behaviour of individual fibrin fibres. Using these results we developed a new structural model of protofibril organisation within fibrin fibres that fully explains their strain stiffening, relatively low modulus and their high, largely variable, extensibility.

Fibrinogen induces inflammatory responses via the immune activating receptor LILRA2.

The leukocyte immunoglobulin-like receptor (LILR) family, a group of primate-specific immunoreceptors, is widely expressed on most immune cells and regulates immune responses through interactions with various ligands. The inhibitory type, LILRB, has been extensively studied, and many ligands, such as HLA class I, have been identified. However, the activating type, LILRA, is less understood. We have previously identified microbially cleaved immunoglobulin as a non-self-ligand for LILRA2. In this study, we identified fibrinogen as an endogenous ligand for LILRA2 using mass spectrometry. Although human plasma contains fibrinogen in abundance in its soluble form, LILRA2 only recognizes solid-phase fibrinogen. In addition to the activating LILRA2, fibrinogen was also recognized by the inhibitory LILRB2 and by soluble LILRA3. In contrast, fibrin was recognized by LILRB2 and LILRA3, but not by LILRA2. Moreover, LILRA3 bound more strongly to fibrin than to fibrinogen and blocked the LILRB2-fibrinogen/fibrin interaction. These results suggest that morphological changes in fibrinogen determine whether activating or inhibitory immune responses are induced. Upon recognizing solid-phase fibrinogen, LILRA2 activated human primary monocytes and promoted the expression of various inflammation-related genes, such as chemokines, as revealed by RNA-seq analysis. A blocking antibody against LILRA2 inhibited the fibrinogen-induced inflammatory responses, indicating that LILRA2 is the primary receptor of fibrinogen. Taken together, our findings suggest that solid-phase fibrinogen is an inflammation-inducing endogenous ligand for LILRA2, and this interaction may represent a novel therapeutic target for inflammatory diseases.

Elevated fibrinogen-albumin ratio is an adverse prognostic factor for patients with primarily resected gastroesophageal adenocarcinoma.

PURPOSE: Serum fibrinogen and albumin play important roles in systemic inflammation and are implicated in tumor progression. The fibrinogen-to-albumin ratio (FAR) has shown a prognostic impact in several malignancies. This study aims to assess the prognostic value of the pretherapeutic FAR in patients with adenocarcinoma of the gastroesophageal junction (AEG) who underwent upfront resection. METHODS: Consecutive patients who underwent surgical resection at the Department of Surgery at the Medical University of Vienna between 1992 and 2014 were included into this study. Optimal cut-off values were determined with the receiver-operating characteristic (ROC) curve, uni- and multivariate analyzes were calculated by the Cox proportional hazard regression model for overall survival (OS). RESULTS: Among 135 included patients, the majority were male (79.26%), with a mean age of 66.53 years. Elevated FAR correlated significantly (p = 0.002) with shorter OS in univariate analysis, also confirmed as independent prognostic factor (p = 0.005) in multivariable analysis. The ROC curve of FAR (AUC = 0.744) outperformed fibrinogen (AUC = 0.738) and albumin (AUC = 0.378) in predicting OS for AEG patients. CONCLUSION: The FAR serves as an independent prognostic factor for OS in patients undergoing primarily resection for AEG. Given its routine availability and ease of calculation, FAR could help in diagnosis and treatment selection for AEG patients. Further validation studies are warranted to confirm these findings conclusively.

Proteomic analysis and experimental validation reveal the blood-brain barrier protective of Huanshaodan in the treatment of SAMP8 mouse model of Alzheimer's disease.

BACKGROUND: Huanshaodan (HSD) is a Chinese Herbal Compound which has a definite clinical effect on Alzheimer's disease (AD), however, the underlying mechanism remains unclear. The aim of this study is to preliminarily reveal the mechanism of HSD in the treatment of AD model of SAMP8 mice. METHODS: Chemical composition of HSD and its drug-containing serum were identified by Q-Orbitrap high resolution liquid mass spectrometry. Six-month-old SAMP8 mice were treated with HSD and Donepezil hydrochloride by gavage for 2 months, and Wogonin for 28 days. Behavioral test was performed to test the learning and memory ability of mice. Immunofluorescence (IF) or Western-blot methods were used to detect the levels of pSer404-tau and ß-amyloid (Aß) in the brain of mice. Hematoxylin-eosin (H&E) staining and Transmission electron microscopy (TEM) assay was applied to observe the pathological changes of neurons. Proteomic technology was carried out to analyze and identify the protein network of HSD interventions in AD. Then the pathological process of the revealed AD-related differential proteins was investigated by IF, Q-PCR, Western-blot, Fluorescence in situ hybridization (FISH) and 16S rRNA sequencing methods. RESULTS: The results showed that HSD and Wogonin, one of the components in its drug-containing serum, can effectively improve the cognitive impairments of SAMP8 mice, protect hippocampal neurons and synapses, and reduce the expression of pSer404-tau and Aß. HSD and Wogonin reduced the levels of fibrinogen ß chain (FGB) and γ chain (FGG), the potential therapeutic targets revealed by proteomics analysis, reduced the colocalization of FGB and FGG with Aß, ionized calcium binding adaptor molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), increased level of and myelin basic protein (MBP). Meanwhile, HSD and Wogonin increased ZO-1 and Occludin levels, improved brain microvascular injury, and reduced levels of bacteria/bacterial DNA and lipopolysaccharide (LPS) in the brain of mice. In addition, 16S rRNA sequencing indicated that HSD regulated the structure of intestinal microbiota of mice. CONCLUSION: The effects of HSD on AD may be achieved by inhibiting the levels of fibrinogen and the interactions on glia cells in the brain, and by modulating the structure of intestinal microbiota and improving the blood-brain barrier function.

The Predictive Value of the Fibrinogen-Albumin-Ratio Index on Surgical Outcomes in Patients with Advanced High-Grade Serous Ovarian Cancer.

BACKGROUND/OBJECTIVES: The present study evaluates predictive implications of the pretherapeutic Fibrinogen-Albumin-Ratio Index (FARI) in high-grade serous ovarian cancer (HGSOC) patients undergoing primary cytoreductive surgery. METHODS: This retrospective study included 161 patients with HGSOC International Federation of Gynecology and Obstetrics (FIGO) stage ≥ IIb, who underwent primary cytoreductive surgery followed by platinum-based chemotherapy. Associations between the FARI and complete tumor resection status were described by receiver operating characteristics, and binary logistic regression models were fitted. RESULTS: Higher preoperative FARI values correlated with higher ascites volumes (r = 0.371, p < 0.001), and higher CA125 levels (r = 0.271, p = 0.001). A high FARI cut at its median (≥11.06) was associated with lower rates of complete tumor resection (OR 3.13, 95% CI [1.63-6.05], p = 0.001), and retrained its predictive value in a multivariable model independent of ascites volumes, CA125 levels, FIGO stage, and Charlson Comorbidity Index (CCI). CONCLUSIONS: The FARI appears to act as a surrogate for higher intra-abdominal tumor load. After clinical validation, FARI could serve as a readily available serologic biomarker to complement preoperative patient assessment, helping to identify patients who are likely to achieve complete tumor resection during primary cytoreductive surgery.

Plasma fibrinogen degradation products with salivary coagulopathy in OSMF among Indians.

Oral submucous fibrosis (OSMF) produces changes localized to oral cavity. Hence, it is reasonable to assume that saliva may have an important role in its etiology. This prospective case control study included 37 patients with OSMF which were compared with age and gender matched healthy controls. Salivary coagulopathy procedures as described by Chatuvedi et al. and quantification of plasma fibrinogen degradation products using a commercially available kit were carried out. The obtained data was analyzed using Chi-square tests and Tukey HSD test. The salivary coagulopathy was strongly indicated in saliva of OSMF patients and was dependent on the severity of disease. There were also increased levels of plasma fibrinogen degradation products compared to the controls and were found to have a statistically significant correlation with increasing clinical grades of oral submucous fibrosis (p≤ 0.05).

Safety of Fibrinogen Concentrate for Correcting Perioperative Bleeding-Associated Hypofibrinogenemia in Adults: A Single-Center Experience.

Background: Surgery often leads to bleeding associated with hypofibrinogenemia. Supplementation with fibrinogen concentrate appears to be effective and safe, although findings from studies are inconsistent. The primary aim of this study was to assess the safety of fibrinogen concentrate during the perioperative period. Methods: This single-centre, prospective, observational study included adult patients undergoing scheduled or emergency surgery related to bleeding coagulopathy and the administration of fibrinogen concentrate. Patients were followed until their discharge from the institution. Comprehensive data were collected, including age, sex, type of surgery, associated comorbidities, anticoagulant and/or anti-aggregating therapy, and the number of blood transfusions. Laboratory data on plasma fibrinogen concentration, haemoglobin, and platelet count before and after surgery were also collected. The primary outcomes were the mortality rate at discharge and any reported thrombotic or thromboembolic events, including deep vein thrombosis, pulmonary embolism, and myocardial infarction. Results: The study included 91 adult patients who had undergone surgery, with 29 surgeries (32%) conducted in an emergency setting. The mean age was 59.2 years, and 53.8% were male. Major bleeding occurred in 29 cases, mainly in older males and those on anticoagulant therapy. The pre-operative fibrinogen level averaged 161 mg/dL, and the average dosage of fibrinogen concentrate administered was 2.7 g. Eight patients died (8.8%), mostly due to septic or cardiogenic shock, with deaths being more frequent in emergency settings. Thromboembolic events occurred in eight patients, none of whom died. No additional adverse events directly related to the administration of fibrinogen concentrate were reported. Conclusions: Our findings suggest a favourable safety profile for fibrinogen concentrate in surgical patients, as evidenced by a low incidence of deaths and thromboembolic events, which were primarily attributed to other factors. Future research should strive to increase statistical robustness to further illuminate clinically significant patient safety measures.

Quantitative and functional changes in platelets and fibrinogen following cardiopulmonary by-pass in children.

Introduction: Cardiopulmonary bypass (CPB) causes coagulopathy, increasing the risk of postoperative bleeding and mortality. The underlying causes of post-CPB coagulopathy and the factors associated with its occurrence are not yet fully understood. This study assesses platelet and fibrinogen concentration and function following CPB in children with congenital heart diseases (CHD). Methods: We analyzed prospective data from 104 patients aged 0-16 years who underwent CPB surgery for CHD. Blood samples were collected before surgery and within 30 min of CPB completion. In addition to usual coagulation tests, functional analyses were performed using point of care systems with thromboelastometry and impedance aggregometry. Results: Platelet count, fibrinogen concentration, and platelet and fibrinogen activities significantly decreased after CPB. The duration of CPB was directly associated with a reduction in platelet count and fibrinogen level (r = -0.38, p < 0.001; r = -0.21, p = 0.03, respectively), but not with their measured activity. Postoperative percentages of baseline values for platelet count (58.36% [43.34-74.44] vs. 37.44% [29.81-54.17], p < 0.001) and fibrinogen concentration (73.68% [66.67-82.35] vs. 65.22% [57.89-70.83], p < 0.001) were significantly higher in patients who did not experience hypothermia during surgery. Age was inversely associated with the decrease in platelet count (r = 0.63, p < 0.001), TRAPTEM AUC (r = 0.43, p < 0.001), fibrinogen concentration (r = 0.44, p < 0.001) and FIBTEM MCF (r = 0.57, p < 0.001). Conclusion: Post-CPB coagulopathy is multifactorial and not solely attributed to hemodilution. It also involves functional changes in coagulation cascade components, which can be demonstrated by thromboelastometry and impedance aggregometry. Young children, patients requiring prolonged CPB surgery, or those experiencing hypothermia are particularly affected.

Exploring the effects of 4-chloro-o-phenylenediamine on human fibrinogen: A comprehensive investigation via biochemical, biophysical and computational approaches.

Fibrinogen (Fg), an essential plasma glycoprotein involved in the coagulation cascade, undergoes structural alterations upon exposure to various chemicals, impacting its functionality and contributing to pathological conditions. This research article explored the effects of 4-Chloro-o-phenylenediamine (4-Cl-o-PD), a common hair dye component (IUPAC = 1-Chloro-3,4-diaminobenzene), on human fibrinogen through comprehensive computational, biophysical, and biochemical approaches. The formation of a stable ligand-protein complex is confirmed through molecular docking and molecular dynamics simulations, revealing possible interaction having a favorable -4.8 kcal/mol binding energy. Biophysical results, including UV-vis and fluorescence spectroscopies, corroborated with the computational findings, whereas Fourier transform infrared spectroscopy (FT-IR) and circular dichroism spectroscopy (CD) provide insights into the alterations of secondary structures upon interaction with 4-Cl-o-PD. Anilinonaphthalene-sulfonic acid (ANS) fluorescence showed a partially unfolded protein, with enhanced α to ß-sheet transition as evidenced by thioflavin T (ThT) spectroscopy and microscopy. Moreover, biochemical assays confirmed the formation of carbonyl compounds that may be responsible for the oxidation of methionine residues in fibrinogen. Electrophoresis and electron microscopy confirmed the formation of aggregates. Our findings elucidate the interaction pattern of 4-Cl-o-PD with Fg, leading to structural perturbation, which may have potential implications for fibrinogen misfolding or its aggregation. Protein aggregation or its misfolded products affect peripheral tissues and the central nervous system. Many chronic progressive diseases, like type II diabetes mellitus, Alzheimer's disease, Parkison's disease, and Creutzfeldt-Jakob disease are associated with intrinsically aberrant disordered proteins. Understanding these interactions may offer new perspectives on the safety and biocompatibility of dye compounds, which may contribute to developing improved strategies for acquired amyloidogenesis.

Preoperative plasma fibrinogen level is a risk factor for the long-term survival of postmenopausal women after surgery for breast cancer.

BACKGROUND: Studies have indicated an association between fibrinogen levels and the prognosis of breast cancer patients. However, fibrinogen levels are notably susceptible to fluctuations due to the menstrual cycle. This study explored the relationship between preoperative plasma fibrinogen levels and the prognosis of postmenopausal breast cancer women after surgery. METHOD: 855 patients with postmenopausal breast cancer were monitored for 10 years. Cox proportional hazards regression models were used to perform univariate and multivariate analyses to identify factors that are of substantial prognostic value. RESULTS: The median follow-up was 77 months (51-105 months), and the maximum 142 months. Over the follow-up period, 65 deaths (7.6 %) were recorded. Multivariate Cox regression results show that preoperative plasma fibrinogen level (hazard ratio [HR] =1.615, 95 % confidence interval [CI]: 1.233-2.115) and age (HR = 1.626, 95%CI: 1.250-2.116) were independent risk factors for 10-year overall survival after surgery in postmenopausal breast cancer patients, while endocrine therapy (HR = 0.414, 95%CI: 0.202-0.846) was an independent protective factor. Multivariate Cox regression results also show preoperative plasma fibrinogen level was an independent risk factor for 10-year disease-free survival (HR = 1.398, 95 % CI: 1.137-1.719) and 10-year distant metastasis-free survival (HR = 1.436, 95%CI: 1.153-1.787). CONCLUSION: Elevated pretreatment plasma fibrinogen levels are associated with a poorer long-term prognosis in postmenopausal breast cancer patients following surgical treatment.

Predictive Value of the D-Dimer-to-Fibrinogen Ratio for Acute Kidney Injury after Living-Donor Liver Transplantation: A Retrospective Observational Cohort Study Using Logistic Regression and Propensity Score Matching Analyses.

Background/Objectives: Liver transplantation (LT) is typically performed as a surgery to treat end-stage liver disease (ESLD). Factors influencing acute kidney injury (AKI) post-living-donor LT (LDLT) have been identified; however, the potential role of the D-dimer-to-fibrinogen ratio (DFR) in predicting AKI remains unexplored. Therefore, we analyzed the relationship between DFR levels and the occurrence of AKI following LT. Methods: We retrospectively analyzed 648 recipients after 76 were excluded based on the exclusion criteria. Multivariate logistic regression and propensity score (PS) matching analyses were performed to evaluate the association between a high DFR (>1.05) and AKI. Results: After LDLT, AKI was observed in 148 patients (22.8%). A high DFR (>1.05) was independently associated with AKI. Multivariate logistic regression analysis showed that patients with a DFR above this threshold were four times more susceptible to AKI than those with a low DFR. A high DFR was also significantly associated with AKI in the propensity score-matched patients. Conclusions: Our findings suggest that incorporating preoperative DFR assessment into the management of patients undergoing LDLT could enhance the risk stratification for postoperative AKI.

Insights into the fabrication and antibacterial effect of fibrinogen hydrolysate-carrageenan loading apigenin and quercetin composite hydrogels.

Escherichia coli and Staphylococcus aureus are the most prevalent pathogenic bacteria, often resulting in the foodborne disease outbreaks through food spoilage and foodborne infections. To prevent and control food spoilage and foodborne infections induced by Escherichia coli and Staphylococcus aureus, the antibacterial hydrogels were fabricated using fibrinogen hydrolysate-carrageenan (AHs-C) and flavonoids (apigenin and quercetin), and the antibacterial effect of the composite hydrogels against Escherichia coli and Staphylococcus aureus was further investigated. The results of mechanical property exhibited that the composite hydrogels with 0.2 % of apigenin and quercetin (AHs-C-Ap/Que) showed the highest hardness and swelling property compared with the separate addition of apigenin or quercetin. Scanning electron microscopy and atomic force microscopy showed that the dense networks were formed in the hydrogels of AHs-C-Ap/Que., and the average roughness of AHs-C-Ap/Que. significantly increased to 30.70 nm compared with AHs-C. 1H NMR and FTIR spectra demonstrated that apigenin and quercetin were bound to AHs-C by hydrogen bond, hydrophobic interaction and Schiff base, where the interactions between Ap/Que. and AHs-C was stronger compared with the separate addition of apigenin or quercetin. The hydrogels of AHs-C-Ap/Que. showed the highest antibacterial capacity and antibacterial adhesion against Escherichia coli and Staphylococcus aureus. The antibacterial adhesion assay showed that 99 % removal ratios for E. coli and S. aureus were observed in AHs-C-Ap/Que. hydrogels, which showed a great potential to prevent food spoilage and foodborne infections.

The prognostic value of preoperative plasma fibrinogen in Asian patients with urothelial cancer: a systematic review and meta-analysis.

Objective: We conducted this meta-analysis to comprehensively explore the prognostic value of the preoperative plasma fibrinogen in Asian patients diagnosed with urothelial cancer (UC). Methods: After a systematic search of Web of Science, PubMed, and Embase before May 2024, we included 10 studies in our meta-analysis. The hazard ratios (HRs) with 95% confidence interval (CI) for overall survival (OS), cancer-specific survival (CSS), recurrence-free survival (RFS), and progression free survival (PFS) were estimated using fixed effect model. Results: This meta-analysis included a total of 2875 patients. UC patients with an elevated preoperative plasma fibrinogen had worse OS (pooled HR: 2.13, 95% CI: 1.81-2.51; P<0.001), CSS (pooled HR: 2.22, 95% CI: 1.83-2.70; P<0.001), RFS (pooled HR: 1.90, 95% CI: 1.59-2.27; P<0.001), and PFS (pooled HR: 2.12, 95% CI: 1.36-3.29, P=0.001). No significant heterogeneity or publication bias was found. Additionally, statistically significant pooled HRs were also calculated in subgroup analysis when stratified by cancer type, country, and cut-off value. Conclusions: The presence of elevated preoperative plasma fibrinogen levels is significantly correlated with unfavorable tumor outcomes in UCs.

Bivariate genome-wide association study of circulating fibrinogen and C-reactive protein levels.

BACKGROUND: Fibrinogen and C-reactive protein (CRP) play an important role in inflammatory pathways and share multiple genetic loci reported in previously published genome-wide association studies (GWAS), highlighting their common genetic background. Leveraging the shared biology may identify further loci pleiotropically associated with both fibrinogen and CRP. OBJECTIVES: To identify novel genetic variants that are pleiotropic and associated with both fibrinogen and CRP, by integrating both phenotypes in a bivariate GWAS by using a multitrait GWAS. METHODS: We performed a bivariate GWAS to identify further pleiotropic genetic loci, using summary statistics of previously published GWAS on fibrinogen (n = 120 246) from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium, consisting of European ancestry samples and CRP (n = 363 228) from UK Biobank, including 5 different population groups. The main analysis was performed using metaUSAT and N-GWAMA. We conducted replication for novel CRP associations to test the robustness of the findings using an independent GWAS for CRP (n = 148 164). We also performed colocalization analysis to compare the associations in identified loci for the 2 traits and Genotype-Tissue Expression data. RESULTS: We identified 87 pleiotropic loci that overlapped between metaUSAT and N-GWAMA, including 23 previously known for either fibrinogen or CRP, 58 novel loci for fibrinogen, and 6 novel loci for both fibrinogen and CRP. Overall, there were 30 pleiotropic and novel loci for both traits, and 7 of these showed evidence of colocalization, located in or near ZZZ3, NR1I2, RP11-72L22.1, MICU1, ARL14EP, SOCS2, and PGM5. Among these 30 loci, 13 replicated for CRP in an independent CRP GWAS. CONCLUSION: Bivariate GWAS identified additional associated loci for fibrinogen and CRP. This analysis suggests fibrinogen and CRP share a common genetic architecture with many pleiotropic loci.

Preoperative fibrinogen level predicts the risk and prognosis of patients with native valve infective endocarditis undergoing valve surgery.

Aim: The aim of this study was to assess the clinical significance and prognostic value of the preoperative fibrinogen (FBG) level in patients with native valve infective endocarditis (NVIE) who underwent valve surgery. Methods: This retrospective study included a total of 163 consecutive patients who were diagnosed with NVIE and underwent valve surgery from January 2019 to January 2022 in our hospital. The primary endpoint was all-cause mortality. Results: All-cause mortality was observed in 9.2% of the patients (n = 15). Body mass index (BMI) was lower in the survival group (p = 0.025), whereas FBG (p = 0.008) and platelet count (p = 0.044) were significantly greater in the survival group than in the death group. Multivariate Cox proportional hazards analysis revealed that FBG (HR, 0.55; 95% CI, [0.32-0.94]; p = 0.029) was an independent prognostic factor for all-cause mortality. Furthermore, Kaplan‒Meier survival curve analysis revealed that patients with low FBG levels (<3.28 g/L) had a significantly greater mortality rate (p = 0.034) than did those with high FBG levels (>3.99 g/L). In the trend analysis, the FBG tertiles were significantly related to all-cause mortality in all three adjusted models, and the p values for trend were 0.017, 0.016, and 0.028, respectively. Conclusion: Preoperative FBG may serve as a prognostic factor for all-cause mortality, and an FBG concentration less than 3.28 g/L was associated with a greater risk of all-cause mortality in NVIE patients undergoing valve surgery.

Molecular characterization, expression and in-silico analysis of fibrinogen-related protein 1 (frep1) in malaria vector Anopheles stephensi.

BACKGROUND: Fibrinogen-related protein 1 (frep1) is a member of the pattern-recognizing receptor family (PRR) which generates an innate immune response after recognizing the pattern associated molecular pattern (PAMP) that occurs on the surface of microorganisms. The main objective of this study is to characterize frep1 and its in-silico analysis in Anopheles stephensi. METHODS AND RESULT: The DNA was extracted from female Anopheles stephensi. PCR was performed for complete analysis of frep1 using specific primers. The gene sequence of frep1 was identified by Sanger sequencing. The bioinformatics structure analysis approach revealed the presence of 3 exons and 4 introns in the frep1. The sequence of frep1 was submitted to NCBI GeneBank with accession number ON817187.1. Quantitative real-time PCR was performed to analyze frep1 expression. At the developmental stage, frep1 is highly expressed in the L1 stage, egg, and adult female mosquito. In addition, frep1 is highly expressed in the tissue fat body, midgut, and salivary gland. After blood-fed, an upregulation of frep1 at 48 h in the midgut, and downregulation in fat body were observed at different time intervals. CONCLUSION: The genomic data of frep1 is encoded by 12,443 bp. The frep1 has a significant role in the early metamorphosis. Its expression in fat body and midgut suggests it could be important for fat metabolism and post-blood digestion. The conserved domain could be targeted for vector control. Further study is required to elucidate its function against malaria parasites to confirm its agonist role in malaria transmission.

Oxidative stress-induced fibrinogen modifications in liver transplant recipients: unraveling a novel potential mechanism for cardiovascular risk.

Background: Cardiovascular events represent a major cause of non-graft-related death after liver transplant. Evidence suggest that chronic inflammation associated with a remarkable oxidative stress in the presence of endothelial dysfunction and procoagulant environment plays a major role in the promotion of thrombosis. However, the underlying molecular mechanisms are not completely understood. Objectives: In order to elucidate the mechanisms of posttransplant thrombosis, the aim of the present study was to investigate the role of oxidation-induced structural and functional fibrinogen modifications in liver transplant recipients. Methods: A case-control study was conducted on 40 clinically stable liver transplant recipients and 40 age-matched, sex-matched, and risk factor-matched controls. Leukocyte reactive oxygen species (ROS) production, lipid peroxidation, glutathione content, plasma antioxidant capacity, fibrinogen oxidation, and fibrinogen structural and functional features were compared between patients and controls. Results: Patients displayed enhanced leukocyte ROS production and an increased plasma lipid peroxidation with a reduced total antioxidant capacity compared with controls. This systemic oxidative stress was associated with fibrinogen oxidation with fibrinogen structural alterations. Thrombin-catalyzed fibrin polymerization and fibrin resistance to plasmin-induced lysis were significantly altered in patients compared with controls. Moreover, steatotic graft and smoking habit were associated with high fibrin degradation rate. Conclusion: ROS-induced fibrinogen structural changes might increase the risk of thrombosis in liver transplant recipients.

Trial Of Pathogen-reduced Cryoprecipitate vs. Cryoprecipitated AHF to Lower Operative Transfusions (TOP-CLOT): study protocol for a single center, prospective, cluster randomized trial.

BACKGROUND: Intraoperative hemorrhage in cardiac surgery increases risk of morbidity and mortality. Low pre-operative and perioperative levels of fibrinogen, a key clotting factor, are associated with severity of hemorrhage and increased transfusion of blood components. The ability to supplement fibrinogen during hemorrhagic resuscitation is delayed 45-60 min because cryoprecipitated antihemophilic factor (cryo AHF) is stored frozen, due to a short post-thaw shelf life. Pathogen Reduced Cryoprecipitated Fibrinogen Complex (INTERCEPT Fibrinogen Complex, IFC) can be kept thawed, at room temperature, for up to 5 days, making it possible to be immediately available for hemorrhaging patients. This trial will investigate if earlier correction of acquired hypofibrinogenemia with IFC in hemorrhaging cardiac surgery patients reduces the total number of perioperatively transfused allogeneic blood products (red blood cells, plasma, and platelets) as compared to cryo AHF. METHODS: This is a single center, prospective, cluster randomized trial with an adaptive design. Acquired hypofibrinogenemia will be assessed by rotational thromboelastometry (ROTEM) and the threshold for cryo AHF/IFC transfusion defined as FIBTEM A10 ≤ 10 mm in bleeding patients. IFC/cryo AHF will be randomized by 1-month blocks. Cardiac surgery patients will be enrolled in the study if they have an eligible procedure and at least one dose of a cryo AHF/IFC product (approximately 2 g fibrinogen) is transfused. Data from the electronic health record, including the blood bank and lab information systems, will be prospectively collected from the health system's data warehouse. DISCUSSION: This trial aims to provide evidence of the clinical efficacy of utilizing readily available thawed IFC during acute bleeding in the cardiac surgery setting compared to traditional cryo AHF. TRIAL REGISTRATION: ClinicalTrials.gov NCT05711524. Feb 3, 2023.

Extending the post-thaw shelf-life of cryoprecipitate when stored at refrigerated temperatures.

BACKGROUND AND OBJECTIVES: The post-thaw shelf-life of cryoprecipitate is 6 h, leading to high wastage. Storage of thawed cryoprecipitate at refrigerated temperatures may be feasible to extend the shelf-life. This study aimed to evaluate the quality of thawed cryoprecipitate stored at 1-6°C for up to 14 days. MATERIALS AND METHODS: Cryoprecipitate (mini- and full-size packs derived from both apheresis and whole blood [WB] collections) was thawed, immediately sampled and then stored at 1-6°C for up to 14 days. Mini-packs were sampled at 6, 24, 48 and 72 h, day 7 and 14; full-size cryoprecipitate was sampled on day 3, 5 or 7. Coagulation factors (F) II, V, VIII, IX, X and XIII, von Willebrand factor (VWF) and fibrinogen were measured using a coagulation analyser. Thrombin generation was measured by calibrated automated thrombogram. RESULTS: FVIII decreased during post-thaw storage; this was significant after 24 h for WB (p = 0.0002) and apheresis (p < 0.0001). All apheresis and eight of 20 WB cryoprecipitate met the FVIII specification (≥ 70 IU/unit) on day 14 post-thaw. Fibrinogen remained stable for 48 h, and components met the specification on day 14 post-thaw. There were no significant differences in VWF (WB p = 0.1292; apheresis p = 0.1507) throughout storage. There were small but significant decreases in thrombin generation lag time, endogenous thrombin potential and time to peak for both WB and apheresis cryoprecipitate. CONCLUSION: Whilst coagulation factors in cryoprecipitate decreased after post-thaw storage, the thawed cryoprecipitate met the Council of Europe specifications when stored at refrigerated temperatures for 7 days.