Thrombosis as an intravascular effector of innate immunity. Nat Rev Immunol. 2013;13:34-45. [PMID: 23222502 DOI: 10.1038/nri3345]

The association between lactate dehydrogenase to serum albumin ratio and in-hospital mortality in patients with pulmonary embolism: a retrospective analysis of the MIMIC-IV database

Background

Lactate dehydrogenase (LDH) and albumin (ALB) were found to be significantly correlated with mortality in pulmonary embolism (PE) patients. However, data regarding the LDH/ALB ratio (LAR) in patients with acute PE are scanty. Therefore, the aim of this study was to investigate the association between LAR and the risk of mortality in patients with acute PE.

Methods

A retrospective cohort study was conducted on patients with acute PE represented in the Medical Information Mart for Intensive Care IV (MIMIC-IV). A receiver operating characteristic (ROC) curve analysis and calibration curve were used to assess the accuracy of the LAR for predicting mortality in patients with acute PE. We utilized Cox regression analysis to determine adjusted hazard ratios (HR) and 95% confidence interval (CI). Survival curves were used to evaluate a connection between the LAR and prognosis in patients with acute PE.

Results

The study comprised 581 patients, and the 30-day all-cause mortality rate was 7.7%. We observed a higher LAR in the non-survival group compared to the surviving group (21.24 ± 21.22 vs. 8.99 ± 7.86, p < 0.0001). The Kaplan-Meier analysis showed that patients with an elevated LAR had a significantly lower likelihood of surviving the 30-day mortality compared to those with a low LAR. Cox regression analysis showed that LAR (HR = 1.04, 95% CI: 1.03-1.05) might have associations with 30-day mortality in patients with acute PE. This result was supported by sensitivity analyses. According to the results of the ROC curve analysis, the LAR's prediction of 30-day mortality in patients with acute PE yielded an area under the ROC curve of 0.73. A calibration curve showed LAR is well calibrated.

Conclusion

Our research suggests LAR monitoring may be promising as a prognostic marker among patients with acute PE.

Deranged Balance of Hemostasis and Fibrinolysis in Disseminated Intravascular Coagulation: Assessment and Relevance in Different Clinical Settings

The disruption of hemostasis/fibrinolysis balance leads to disseminated intravascular coagulation, manifested clinically by bleeding or thrombosis, and multiorgan failure. This study reviews hemostatic assessment and therapeutic strategies that restore this balance in critically ill patients.

Polyunsaturated fatty acid-derived lipid mediator Resolvin D1 alleviates sepsis-induced disseminated intravascular coagulation via Caspase-1/Gasdermin D pyroptotic pathway

BACKGROUND & AIMS

Sepsis-induced disseminated intravascular coagulation (DIC) is characterised by abnormal blood clotting resulting from severe infection, contributing to organ dysfunction in sepsis. Resolvin D1 (RvD1) is an endogenous lipid mediator, synthesised from the omega-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) through enzymatic processes involving 15-LOX and 5-LOX. RvD1 is recognised for its protective properties against various inflammatory conditions. This study aims to investigate its potential to modulate coagulation dysfunction in sepsis and to evaluate coagulation disorders in septic patients.

METHODS

Sepsis models were established by intraperitoneal injection LPS (20 mg/kg) or cecal ligation and puncture (CLP) followed by injection of RvD1 (10 μg/kg) or saline. The impact of RvD1 on coagulation dysfunction was assessed by clotting time and coagulation indicators such as TAT, D-dimer, PAI-1, and fibrinogen. The activity of the coagulation system in vivo was observed by evaluating dynamic microcirculation, platelets and thrombin in mice using intravital microscopy. The effect of RvD1 on pyroptosis was investigated by measuring NOD-like receptor protein 3 (NLRP3), Caspase-1, Caspase-11, and Gasdermin D (GSDMD) levels via western blot. Caspase-1 knockout mice, GSDMD knockout mice and bone marrow-derived macrophages (BMDMs) were used to elucidate the underlying mechanisms. Lastly, the concentration of RvD1 in plasma from septic patients was quantified to explore its relationship with coagulation and pyroptosis.

RESULTS

RvD1 significantly attenuated coagulation dysfunction in septic mice induced by LPS and CLP, and inhibited Caspase-1/GSDMD-dependent pyroptosis in septic mice and bone marrow-derived macrophages. In septic patients, the plasma concentrations of RvD1 was negatively correlated with both coagulation-related indicators and markers of GSDMD activation.

CONCLUSION

The results suggest that RvD1 can improve coagulation dysfunction in sepsis by regulating the Caspase-1/GSDMD pyroptotic pathway. Additionally, the concentration of RvD1 in septic patient plasma is related to prognosis and DIC development. RvD1 could be a potential biomarker and a promising therapeutic alternative in sepsis-induced DIC.

Immunological role of Gas6/TAM signaling in hemostasis and thrombosis

The immune system is an emerging regulator of hemostasis and thrombosis. The concept of immunothrombosis redefines the relationship between coagulation and immunomodulation, and the Gas6/Tyro3-Axl-MerTK (TAM) signaling pathway builds the bridge across them. During coagulation, Gas6/TAM signaling pathway not only activates platelets, but also promotes thrombosis through endothelial cells and vascular smooth muscle cells involved in inflammatory responses. Thrombosis appears to be a common result of a Gas6/TAM signaling pathway-mediated immune dysregulation. TAM TK and its ligands have been found to be involved in coagulation through the PI3K/AKT or JAK/STAT pathway in various systemic diseases, providing new perspectives in the understanding of immunothrombosis. Gas6/TAM signaling pathway serves as a breakthrough target for novel therapeutic strategies to improve disease management. Many preclinical and clinical studies of TAM receptor inhibitors are in process, confirming the pivotal role of Gas6/TAM signaling pathway in immunothrombosis. Therapeutics targeting the TAM receptor show potential both in anticoagulation management and immunotherapy. Here, we review the immunological functions of the Gas6/TAM signaling pathway in coagulation and its multiple mechanisms in diseases identified to date, and discuss the new clinical strategies that may generated by these roles.

Targeting neutrophil extracellular trap accumulation under flow in patients with immune-mediated thrombotic thrombocytopenic purpura

ABSTRACT

Neutrophil NETosis is a unique form of cell death, characterized by the release of decondensed chromatin and antimicrobial contents to the extracellular space, which is involved in inflammation and thrombosis. However, the role of NETosis in the pathogenesis of immune-mediated thrombotic thrombocytopenic purpura (iTTP) and how a targeted therapy affects the accumulation of neutrophil extracellular traps (NETs) under flow remain unknown. Flow cytometry demonstrated that the percentage of neutrophils undergoing NETosis in whole blood from patients with iTTP on admission was significantly increased, with a concurrent decrease in the capacity of inducible NETosis by shigatoxin. After therapy, the percentage of H3Cit+MPO+ neutrophils was significantly reduced, with an improvement in inducible NETosis in these patients. Additionally, little to no NET and thrombus formation was detected underflow in the whole blood from patients with iTTP when platelet counts were very low, but the NET and thrombus formation was dramatically increased following therapy when platelet counts rose to ≥50 × 109/L or were restored to normal with donor platelets. Similarly, there was no thrombus or NET accumulation under flow in the whole blood from vwf-/- mice, but NET accumulation was significantly higher in Adamts13-/- mice than in wild-type mice. Finally, recombinant ADAMTS13 or caplacizumab (or anfibatide) prevented NET and thrombus formation under flow in whole blood from patients with iTTP or from Adamts13-/- mice. These results indicate that neutrophil NETosis and NET formation depend on platelets and von Willebrand factor (VWF) in iTTP, and a targeted therapy such as recombinant ADAMTS13 or caplacizumab may prevent NET and thrombus formation under flow in iTTP.

Serum biomarkers of inflammation and vascular damage upon SARS-Cov-2 mRNA vaccine in patients with thymic epithelial tumors

OBJECTIVES

Thymic epithelial tumors (TET) patients are at high risk of autoimmune and hypoimmune complications. Limited evidence is available on the potential risk of immune-related and inflammatory reactions induced by SARS-Cov-2 vaccine in this patient population.

METHODS

In order to identify subjects at higher risk for vaccine complications, we prospectively evaluated a panel of serum biomarkers related to inflammation (TNF-α, IL-1β, -6, -10, -12, and -17A, IFN-α, β and γ, MPO, MMP-9), and vascular damage (E- and P-selectin, VEGF-A, P-ANCA and MCP-1) in 44 TET patients and in 30 healthy controls along the whole SARS-Cov-2 vaccine cycle.

RESULTS

About 50 % of subjects (either TET and controls) showed an increase of serum biochemical markers of inflammation and endothelial damage with a large heterogeneity of values. Such increase appeared early, after the first dose in control subjects and later, after the second dose in TET patients (in which we observed mainly an increase of inflammatory biomarkers). The values normalized after about 3 months and did not increase after the third, booster dose. No autoimmune or vascular complications were observed in the study subjects and no difference was observed in terms of vaccine response among subjects showing serum biomarkers increase and those who experienced no changes.

CONCLUSIONS

Our data highlight the relevance of Sars-Cov-2 vaccine in TET patients, as it resulted safe and prevented severe COVID-19. However, further studies are awaited to explore the mechanisms and the potential consequences of the observed increase of serum inflammatory and vascular damage biomarkers.

Dissecting thrombus-directed chemotaxis and random movement in neutrophil near-thrombus motion in flow chambers

BACKGROUND

Thromboinflammation is caused by mutual activation of platelets and neutrophils. The site of thromboinflammation is determined by chemoattracting agents release by endothelium, immune cells, and platelets. Impaired neutrophil chemotaxis contributes to the pathogenesis of Shwachman-Diamond syndrome (SDS). In this hereditary disorder, neutrophils are known to have aberrant chemoattractant-induced F-actin properties. Here, we aim to determine whether neutrophil chemotaxis could be analyzed using our previously developed ex vivo assay of the neutrophils crawling among the growing thrombi.

METHODS

Adult and pediatric healthy donors, alongside with pediatric patients with SDS, were recruited for the study. Thrombus formation and granulocyte movement in hirudinated whole blood were visualized by fluorescent microscopy in fibrillar collagen-coated parallel-plate flow chambers. Alternatively, fibrinogen, fibronectin, vWF, or single tumor cells immobilized on coverslips were used. A computational model of chemokine distribution in flow chamber with a virtual neutrophil moving in it was used to analyze the observed data.

RESULTS

The movement of healthy donor neutrophils predominantly occurred in the direction and vicinity of thrombi grown on collagen or around tumor cells. For SDS patients or on coatings other than collagen, the movement was characterized by randomness and significantly reduced velocities. Increase in wall shear rates to 300-500 1/s led to an increase in the proportion of rolling neutrophils. A stochastic algorithm simulating leucocyte chemotaxis movement in the calculated chemoattractant field could reproduce the experimental trajectories of moving neutrophils for 72% of cells.

CONCLUSIONS

In samples from healthy donors, but not SDS patients, neutrophils move in the direction of large, chemoattractant-releasing platelet thrombi growing on collagen.

Continuous veno-venous hemofiltration with oXiris hemofilters for the treatment of Fournier's gangrene: A case report series

Background

Fournier's gangrene (FG) is a severe form of necrotizing fasciitis primarily caused by gram-negative bacteria. FG can rapidly progress to septic shock, resulting in high mortality rates. In the past, the management of the inflammatory response caused by gram-negative bacteria has been limited. Continuous Veno-Venous Hemofiltration with oXiris hemofilters (oXiris-CVVH) has shown promise in adsorbing inflammatory factors and endotoxins, making it an attractive approach for treating FG. This study aims to provide insights into the characteristics of patients with FG and septic shock who have been successfully treated using oXiris-CVVH, based on a series of patient cases.

Results

This study presents the management of 4 cases in the intensive care units of a tertiary hospital in southern China. The use of oXiris-CVVH in patients with septic shock and FG yielded valuable practical insights.

Conclusion

Based on the experience gained from these 4 cases, the utilization of oXiris-CVVH demonstrated potential in reducing the Sequential Organ Failure Assessment (SOFA) score, improving prognosis, and effectively lowering the levels of lactic acid and procalcitonin (PCT) in the blood. Additionally, it facilitated a reduction in the dosage of noradrenaline. Therefore, oXiris-CVVH should be considered as an adjunctive therapy in the treatment of patients with FG and septic shock.

Platelets: Orchestrators of immunity in host defense and beyond

Platelets prevent blood loss during vascular injury and contribute to thrombus formation in cardiovascular disease. Beyond these classical roles, platelets are critical for the host immune response. They guard the vasculature against pathogens via specialized receptors, intracellular signaling cascades, and effector functions. Platelets also skew inflammatory responses by instructing innate immune cells, support adaptive immunosurveillance, and influence antibody production and T cell polarization. Concomitantly, platelets contribute to tissue reconstitution and maintain vascular function after inflammatory challenges. However, dysregulated activation of these multitalented cells exacerbates immunopathology with ensuing microvascular clotting, excessive inflammation, and elevated risk of macrovascular thrombosis. This dichotomy underscores the critical importance of precisely defining and potentially modulating platelet function in immunity.

The unexplored role of alkali and alkaline earth elements (ALAEs) on the structure, processing, and biological effects of bioactive glasses

Bioactive glass has been employed in several medical applications since its inception in 1969. The compositions of these materials have been investigated extensively with emphasis on glass network formers, therapeutic transition metals, and glass network modifiers. Through these experiments, several commercial and experimental compositions have been developed with varying chemical durability, induced physiological responses, and hydroxyapatite forming abilities. In many of these studies, the concentrations of each alkali and alkaline earth element have been altered to monitor changes in structure and biological response. This review aims to discuss the impact of each alkali and alkaline earth element on the structure, processing, and biological effects of bioactive glass. We explore critical questions regarding these elements from both a glass science and biological perspective. Should elements with little biological impact be included? Are alkali free bioactive glasses more promising for greater biological responses? Does this mixed alkali effect show increased degradation rates and should it be employed for optimized dissolution? Each of these questions along with others are evaluated comprehensively and discussed in the final section where guidance for compositional design is provided.

Dysregulated Coagulation and Fibrinolysis Are Present in Patients Admitted to the Emergency Department with Acute Hypoxemic Respiratory Failure: A Prospective Study

Acute hypoxemic respiratory failure (AHRF) is defined as acute and progressive, and patients are at a greater risk of developing acute respiratory distress syndrome (ARDS). Until now, most studies have focused on prognostic and diagnostic biomarkers in ARDS. Since there is evidence supporting a connection between dysregulated coagulant and fibrinolytic pathways in ARDS progression, it is plausible that this dysregulation also exists in AHRF. The aim of this study was to explore whether levels of soluble endothelial protein C receptor (sEPCR) and plasminogen differentiate patients admitted to the emergency department (ED) with AHRF. sEPCR and plasminogen levels were measured in 130 AHRF patients upon ED presentation by ELISA. Our results demonstrated that patients presenting to the ED with AHRF had elevated levels of sEPCR and plasminogen. It seems that dysregulation of coagulation and fibrinolysis occur in the early stages of respiratory failure requiring hospitalisation. Further research is needed to fully comprehend the contribution of sEPCR and plasminogen in AHRF.

Angiopoietin2 is associated with coagulation activation and tissue factor expression in extracellular vesicles in COVID-19

Coagulation activation in immunothrombosis involves various pathways distinct from classical hemostasis, offering potential therapeutic targets to control inflammation-induced hypercoagulability while potentially sparing hemostasis. The Angiopoietin/Tie2 pathway, previously linked to embryonic angiogenesis and sepsis-related endothelial barrier regulation, was recently associated with coagulation activation in sepsis and COVID-19. This study explores the connection between key mediators of the Angiopoietin/Tie2 pathway and coagulation activation. The study included COVID-19 patients with hypoxia and healthy controls. Blood samples were processed to obtain platelet-free plasma, and frozen until analysis. Extracellular vesicles (EVs) in plasma were characterized and quantified using flow cytometry, and their tissue factor (TF) procoagulant activity was measured using a kinetic chromogenic method. Several markers of hemostasis were assessed. Levels of ANGPT1, ANGPT2, and soluble Tie2 correlated with markers of coagulation and platelet activation. EVs from platelets and endothelial cells were increased in COVID-19 patients, and a significant increase in TF+ EVs derived from endothelial cells was observed. In addition, ANGPT2 levels were associated with TF expression and activity in EVs. In conclusion, we provide further evidence for the involvement of the Angiopoietin/Tie2 pathway in the coagulopathy of COVID-19 mediated in part by release of EVs as a potential source of TF activity.

Design and Synthesis of P(AAm-co-NaAMPS)-Alginate-Xanthan Hydrogels and the Study of Their Mechanical and Rheological Properties in Artificial Vascular Graft Applications

Cardiovascular diseases (CVDs) are the number one cause of mortality among non-communicable diseases worldwide. Expanded polytetrafluoroethylene (ePTFE) is a widely used material for making artificial vascular grafts to treat CVDs; however, its application in small-diameter vascular grafts is limited by the issues of thrombosis formation and intimal hyperplasia. This paper presents a novel approach that integrates a hydrogel layer on the lumen of ePTFE vascular grafts through mechanical interlocking to efficiently facilitate endothelialization and alleviate thrombosis and restenosis problems. This study investigated how various gel synthesis variables, including N,N'-Methylenebisacrylamide (MBAA), sodium alginate, and calcium sulfate (CaSO4), influence the mechanical and rheological properties of P(AAm-co-NaAMPS)-alginate-xanthan hydrogels intended for vascular graft applications. The findings obtained can provide valuable guidance for crafting hydrogels suitable for artificial vascular graft fabrication. The increased sodium alginate content leads to increased equilibrium swelling ratios, greater viscosity in hydrogel precursor solutions, and reduced transparency. Adding more CaSO4 decreases the swelling ratio of a hydrogel system, which offsets the increased swelling ratio caused by alginate. Increased MBAA in the hydrogel system enhances both the shear modulus and Young's modulus while reducing the transparency of the hydrogel system and the pore size of freeze-dried samples. Overall, Hydrogel (6A12M) with 2.58 mg/mL CaSO4 was the optimal candidate for ePTFE-hydrogel vascular graft applications due to its smallest pore size, highest shear storage modulus and Young's modulus, smallest swelling ratio, and a desirable precursor solution viscosity that facilitates fabrication.

The effects of emicizumab on in vitro coagulation and fibrinolysis parameters in patients with disseminated intravascular coagulation with and without addition of anti-FVIII antibody

BACKGROUND

Emicizumab (Emi) is used as haemostatic prophylaxis for patients with haemophilia A (PwHA). Disseminated intravascular coagulation (DIC) is a condition characterized by persistent systemic activation of coagulation, but there is yet no information on coagulation and fibrinolysis potentials in Emi-treated PwHA with DIC.

AIM

To examine the effect of Emi on coagulation and fibrinolysis potentials in HA-model DIC plasmas.

METHODS

Plasma from a patient with sepsis-DIC (seven patients) was treated with anti-factor (F)VIII monoclonal antibody (HA-model DIC plasma) and incubated with Emi (50 µg/mL). The plasma was then assessed using clot-fibrinolysis waveform analysis (CFWA). Coagulation and fibrinolysis parameters were expressed as ratios relative to normal plasma (|min1|-ratio and |FL-min1|-ratio, respectively).

PATIENTS AND RESULTS

In case 1, coagulant potential was slightly high and fibrinolytic potential was extremely low, presenting a coagulant-dominant state (|min1|-ratio/|FL-min1|-ratio: 1.1/.38). In cases 2-5, fibrinolytic potential was not suppressed, but there were marked hypercoagulant potentials, indicating relative coagulant-dominant states. In case 6, coagulant and fibrinolytic potentials were increased but well balanced (|min1|-ratio/|FL-min1|-ratio: 1.38/1.28). In case 7, both potentials were severely deteriorated in not only CFWA but also the thrombin/plasmin generation assay. The addition of Emi into the HA-model DIC plasmas increased |min1|-ratio values in all cases, but the coagulant potentials did not exceed the initial ones (DIC plasma before treatment with anti-FVIII antibody).

CONCLUSIONS

The presence of Emi in the HA-model DIC plasma improved coagulation potentials, but did not increase coagulation potentials beyond those of DIC plasma in non-HA states.

Assessment of hemostatic profile in neonates with necrotizing enterocolitis using Rotational Thromboelastometry (ROTEM)

BACKGROUND

This study aimed to explore the hemostatic profile of neonates with necrotizing enterocolitis (NEC) using Rotational Thromboelastometry (ROTEM) and to investigate if ROTEM parameters have the capacity to play a role in the differentiation of NEC from sepsis at the disease onset.

METHODS

This observational study included 62 neonates (mean gestational age 31.6 weeks and mean birth weight 1620g) hospitalized in a neonatal intensive care unit. The neonates were categorized in three groups: neonates with NEC (Bell stage II and above), neonates with sepsis and healthy neonates and they were matched 1:1:1 with regards to gestational age, delivery mode, and sex. Clinical, laboratory data as well as measurements of ROTEM parameters at disease onset were recorded.

RESULTS

ROTEM parameters differed between neonates with NEC and neonates with sepsis, indicating that NEC results in accelerated clot formation and higher clot strength compared to sepsis. The EXTEM CFT and A10 parameters demonstrated the highest diagnostic performance for NEC in terms of discrimination between NEC and sepsis (AUC, 0.997; 95% CI: 0.991-1.000 and 0.973; 95% CI: 0.932-1.000, respectively).

CONCLUSIONS

Neonates with NEC manifested accelerated clot formation and higher clot strength compared to septic and healthy neonates, as these were expressed by ROTEM parameters.

IMPACT

This work reports data on the hemostatic profile of neonates with necrotizing enterocolitis (NEC) using Rotational Thromboelastometry (ROTEM) and the capacity of ROTEM parameters in differentiating of NEC from sepsis at the disease onset. Neonates with NEC present acceleration of coagulation and exhibit a hypercoagulable profile, as this is expressed by ROTEM parameters, in comparison to septic and healthy neonates. ROTEM parameters demonstrated a good diagnostic capacity in differentiating NEC from sepsis at the disease onset.

Development and Validation of a Predictive Model for Acute Kidney Injury in Sepsis Patients Based on Recursive Partition Analysis

BACKGROUND

Sepsis-associated acute kidney injury (SA-AKI) is a critical condition with significant clinical implications, yet there is a need for a predictive model that can reliably assess the risk of its development. This study is undertaken to bridge a gap in healthcare by creating a predictive model for SA-AKI with the goal of empowering healthcare providers with a tool that can revolutionize patient care and ultimately lead to improved outcomes.

METHODS

A cohort of 615 patients afflicted with sepsis, who were admitted to the intensive care unit, underwent random stratification into 2 groups: a training set (n = 435) and a validation set (n = 180). Subsequently, a multivariate logistic regression model, imbued with nonzero coefficients via LASSO regression, was meticulously devised for the prognostication of SA-AKI. This model was thoughtfully rendered in the form of a nomogram. The salience of individual risk factors was assessed and ranked employing Shapley Additive Interpretation (SHAP). Recursive partition analysis was performed to stratify the risk of patients with sepsis.

RESULTS

Among the panoply of clinical variables examined, hypertension, diabetes mellitus, C-reactive protein, procalcitonin (PCT), activated partial thromboplastin time, and platelet count emerged as robust and independent determinants of SA-AKI. The receiver operating characteristic curve analysis for SA-AKI risk discrimination in both the training set and validation set yielded an area under the curve estimates of 0.843 (95% CI: 0.805 to 0.882) and 0.834 (95% CI: 0.775 to 0.893), respectively. Notably, PCT exhibited the most conspicuous influence on the model's predictive capacity. Furthermore, statistically significant disparities were observed in the incidence of SA-AKI and the 28-day survival rate across high-risk, medium-risk, and low-risk cohorts (P < .05).

CONCLUSION

The composite predictive model, amalgamating the quintet of SA-AKI predictors, holds significant promise in facilitating the identification of high-risk patient subsets.

Platelet Physiology

Platelets are the smallest blood cells, numbering 150 to 350 × 109/L in healthy individuals. The ability of activated platelets to adhere to an injured vessel wall and form aggregates was first described in the 19th century. Besides their long-established roles in thrombosis and hemostasis, platelets are increasingly recognized as pivotal players in numerous other pathophysiological processes including inflammation and atherogenesis, antimicrobial host defense, and tumor growth and metastasis. Consequently, profound knowledge of platelet structure and function is becoming more important in research and in many fields of modern medicine. This review provides an overview of platelet physiology focusing particularly on the structure, granules, surface glycoproteins, and activation pathways of platelets.

Neutrophil extracellular trap biomarkers in aneurysmal subarachnoid hemorrhage: early decline of DNase 1 activity associated with delayed cerebral ischemia

Introduction

High-mobility group box 1 (HMGB1) protein is a critical mediator of neutrophil extracellular trap (NET) formation (NETosis). Myeloperoxidase (MPO)-DNA complexes, a biomarker of NETs, and HMGB1 have been associated with delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). Additional mechanistic NET-related biomarkers and their role in the neuroinflammatory cascade surrounding DCI remain to be explored.

Methods

A post-hoc analysis of a prospective, blinded, single-center biomarker observational study was performed. De novo measurements of serum citrullinated histone H3-DNA complexes (H3Cit-DNA), peptidylarginine deiminase 4 (PAD4), cell-free DNA (cf-DNA), and DNase 1 activity were conducted on admission (D0) and day 4 (D4). Delayed cerebral infarction (DCI) was defined as new cerebral infarction on CT head not present on the post-treatment scan.

Results

H3Cit-DNA, PAD4, cf-DNA, and DNase 1 activity were within quantifiable ranges in all serum samples analyzed at D0 and D4. Admission biomarker levels were not associated with DCI development. From D0 to D4, in both the DCI and the non-DCI groups, H3Cit-DNA levels significantly decreased, cf-DNA levels significantly increased, and PAD4 levels remained stable. In contrast, DNase 1 activity significantly decreased from D0 to D4 in the DCI group (p < 0.001) but not in the non-DCI group.

Conclusion

This exploratory analysis demonstrated NET-related biomarkers such as H3Cit-DNA, PAD4, cf-DNA, and DNase 1 activity in all aSAH patients. A decline of systemic DNase 1 activity in the early phase might increase the risk of delayed cerebral ischemia.

Antithrombotic pharmacodynamics and metabolomics study in raw and processed products of Whitmania pigra Whitman

Objective

As a traditional Chinese medicine, leech has obvious pharmacological activities in anticoagulantion and antithrombosis. Whitmania pigra Whitman (WP) is the most commonly used leech in the Chinese market. It is often used in clinical applications after high-temperature processing by talcum powder to remove the fishy taste and facilitate crushing. The anticoagulant and thrombolytic active ingredients are protein and polypeptide, which may denaturate and lose activity after high-temperature processing. The rationality of its processing has been questioned in recent years. This study aims to investigate the effect of talcum powder scalding on the antithrombotic activity of WP in vivo and to discuss its pharmacodynamic mechanism in vivo.

Methods

Raw and talcum-powdered processed WP were administered intragastrically for 14 days, and carrageenan was injected intraperitoneally to prepare a mouse model of tail vein thrombosis. The incidence rate of tail vein thrombosis and the thrombus area under pathological tissue sections were calculated to evaluate the antithrombotic effect between raw and processed WP. Non-targeted metabolomics was conducted using UPLC-Q-TOF/MS technology to analyze the changes of small molecule metabolites in the body after administration of WP.

Results

After intragastric administration, both the raw product and the processed product of WP could inhibit the thrombosis induced by carrageenan, and the processed product had a more apparent antithrombotic effect than the raw product. The administration of WP could regulate the changes of some small molecular metabolites, such as amino acids, lipids, and steroids, in Sphingolipid metabolism and Glycerophospholipid metabolism.

Conclusions

Based on the results of pharmacodynamics and metabolomics, processed WP will not reduce the antithrombotic activity of WP. This study provided a scientific basis for the rational use of leeches.

Combination Administration of Heparin and Nitroglycerin for the Treatment of Polycaprolactone-Induced Intravascular Embolism: A Preclinical Investigation

BACKGROUND

As a new-generation collagen stimulator, polycaprolactone (PCL) containing filler has been extensively applied in facial dermal fillers and other medical aesthetic fields. However, inadvertent intravascular injection of PCL may result in complications such as tissue edema, flap necrosis, and even blindness. To date, there is no effective treatment for PCL-induced intravascular embolism.

OBJECTIVES

The aim of this study was to identify a viable resolution for the embolism resulting from intravascular administration of PCL-containing fillers.

METHODS

Two different animal experiments were performed: (1) PCL-induced rat inferior epigastric arteries embolism, followed by gross observation, histological evaluation, and cytokines analysis from serum; and (2) PCL-induced rabbit auricular artery embolism, immediately treated with heparin and nitroglycerin. The ears were then evaluated by gross observation, Laser speckle imaging, in vivo imaging system (IVIS) imaging, and histological evaluation. Saline and hyaluronic acids (HA) were used as controls, hyaluronidase was used as a positive drug.

RESULTS

In a rat model of inferior epigastric arteries embolism, both intravascular injection of HA and PCL resulted in flap necrosis, indicating that the filler-induced intravascular embolism can lead to serious complications. In a rabbit model of auricular artery embolism, the combination treatment of heparin and nitroglycerin resulted in a relative blood reperfusion recovery of 80% in the ischemic area of the PCL group on day 7 post-operation, which was comparable to that of the HA group treated with hyaluronidase. Histological analysis revealed that the administration of heparin and nitroglycerin significantly attenuated intravascular thrombosis formation and inflammatory cell aggregation.

CONCLUSIONS

The combination of heparin and nitroglycerin effectively restores blood flow reperfusion in the intravascular embolization caused by PCL filler injection, alleviates local tissue edema and flap necrosis. These findings offer a novel approach for future clinical management of intravascular embolization with PCL-containing filler injection.

NO LEVEL ASSIGNED

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Under the dual effect of inflammation and pulmonary fibrosis, CTD-ILD patients possess a greater susceptibility to VTE

As an autoimmune disease, the persistent systemic inflammatory response associated with connective tissue disease (CTD) is involved in the development of venous thromboembolism (VTE). However, clinical data showed that the risk of VTE in patients differed between subtypes of CTD, suggesting that different subtypes may have independent mechanisms to promote the development of VTE, but the specific mechanism lacks sufficient research at present. The development of pulmonary fibrosis also contributes to the development of VTE, and therefore, patients with CTD-associated interstitial lung disease (CTD-ILD) may be at higher risk of VTE than patients with CTD alone or patients with ILD alone. In addition, the activation of the coagulation cascade response will drive further progression of the patient's pre-existing pulmonary fibrosis, which will continue to increase the patient's risk of VTE and adversely affect prognosis. Currently, the treatment for CTD-ILD is mainly immunosuppressive and antirheumatic therapy, such as the use of glucocorticoids and janus kinase-inhibitors (JAKis), but, paradoxically, these drugs are also involved in the formation of patients' coagulation tendency, making the clinical treatment of CTD-ILD patients with a higher risk of developing VTE challenging. In this article, we review the potential risk factors and related mechanisms for the development of VTE in CTD-ILD patients to provide a reference for clinical treatment and prevention.

The value of performance status in predicting venous thromboembolism in lung cancer patients treated with immune checkpoint inhibitors

INTRODUCTION

The incidence of venous thromboembolism (VTE) is notably high in lung cancer patients, particularly among those treated with immune checkpoint inhibitors (ICIs). Previous studies have focused on the relationship between Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) and VTE risk in immune checkpoint inhibitor therapy, but available evidence is inconsistent.

METHODS

The clinical data of lung cancer patients treated with ICIs were collected and analyzed from West China Hospital between January 2018 and March 2022. ECOG PS score was measured on admission. The primary outcome was the incidence of VTE, encompassing both deep vein thrombosis (DVT) and pulmonary embolism (PE). Multivariate logistic regression analysis was conducted to calculate the odds ratio (OR) and 95% confidence interval (95% CI).

RESULTS

A total of 1115 lung cancer patients receiving ICIs were eligible for this study, VTE developed in 105 (9.4%) during the 12-month follow-up, of which 95 (8.5%) had DVT,14 (1.3%) had definite PE. Poor ECOG PS (PS ≥ 2) was associated with an increased risk for VTE (OR = 5.405, 95% CI = 3.067-9.525, P < 0.001), DVT (OR = 4.669, 95% CI = 2.588-8.427, P < 0.001) and PE (OR = 8.413, 95% CI = 2.565-27.600, P < 0.001) after multivariable adjustment in the study cohort.

CONCLUSION

VTE occurred in 9.4% of lung cancer patients treated with ICIs, and poor performance status was associated with an increased risk of VTE.

Embracing cancer complexity: Hallmarks of systemic disease

The last 50 years have witnessed extraordinary developments in understanding mechanisms of carcinogenesis, synthesized as the hallmarks of cancer. Despite this logical framework, our understanding of the molecular basis of systemic manifestations and the underlying causes of cancer-related death remains incomplete. Looking forward, elucidating how tumors interact with distant organs and how multifaceted environmental and physiological parameters impinge on tumors and their hosts will be crucial for advances in preventing and more effectively treating human cancers. In this perspective, we discuss complexities of cancer as a systemic disease, including tumor initiation and promotion, tumor micro- and immune macro-environments, aging, metabolism and obesity, cancer cachexia, circadian rhythms, nervous system interactions, tumor-related thrombosis, and the microbiome. Model systems incorporating human genetic variation will be essential to decipher the mechanistic basis of these phenomena and unravel gene-environment interactions, providing a modern synthesis of molecular oncology that is primed to prevent cancers and improve patient quality of life and cancer outcomes.

Thrombocytopenia in Klebsiella pneumoniae liver abscess: a retrospective study on its correlation with disease severity and potential causes

Objective

Thrombocytopenia is commonly associated with infectious diseases and serves as an indicator of disease severity. However, reports on its manifestation in conjunction with Klebsiella pneumoniae liver abscess (KPLA) are scarce. The present study sought to elucidate the correlation between thrombocytopenia and KPLA severity and delve into the etiological factors contributing to the incidence of thrombocytopenia.

Materials and methods

A retrospective analysis of the clinical data from patients with KPLA admitted between June 2012 and June 2023 was performed. Baseline characteristics, biochemical assessments, therapeutic interventions, complications, and clinical outcomes were compared between patients with and without thrombocytopenia. To investigate the potential etiologies underlying thrombocytopenia, the association between platelet count reduction and thrombophlebitis was examined, with a particular focus on platelet consumption. Furthermore, bone marrow aspiration results were evaluated to assess platelet production anomalies.

Results

A total of 361 KPLA patients were included in the study, among whom 60 (17%) had concurrent thrombocytopenia. Those in the thrombocytopenia group exhibited significantly higher rates of thrombophlebitis (p = 0.042), extrahepatic metastatic infection (p = 0.01), septic shock (p = 0.024), admissions to the intensive care unit (p = 0.002), and in-hospital mortality (p = 0.045). Multivariate analysis revealed that thrombocytopenia (odds ratio, 2.125; 95% confidence interval, 1.114-4.056; p = 0.022) was independently associated with thrombophlebitis. Among the thrombocytopenic patients, eight underwent bone marrow aspiration, and six (75%) had impaired medullar platelet production. After treatment, 88.6% of thrombocytopenic patients (n = 47) demonstrated recovery in their platelet counts with a median recovery time of five days (interquartile range, 3-6 days).

Conclusions

Thrombocytopenia in patients with KPLA is indicative of increased disease severity. The underlying etiologies for thrombocytopenia may include impaired platelet production within the bone marrow and augmented peripheral platelet consumption as evidenced by the presence of thrombophlebitis.

Immune checkpoint inhibitor-associated cardiovascular toxicities: A review

Immune checkpoint inhibitors (ICIs) have revolutionary effects on therapeutic strategies for multiple malignancies. Their efficacy depends on their ability to reactivate the host immune system to fight cancer cells. However, adverse reactions to ICIs are common and involve several organs, limiting their use in clinical practice. Although the incidence of cardiovascular toxicity is relatively low, it is associated with serious consequences and high mortality rates. The primary cardiovascular toxicities include myocarditis, pericarditis, Takotsubo syndrome, arrhythmia, vasculitis, acute coronary syndrome, and venous thromboembolism. Currently, the mechanism underlying ICI-associated cardiovascular toxicity remains unclear and underexplored. The diagnosis and monitoring of ICI-associated cardiovascular toxicities mainly include the following indicators: symptoms, signs, laboratory examination, electrocardiography, imaging, and pathology. Treatments are based on the grade of cardiovascular toxicity and mainly include drug withdrawal, corticosteroid therapy, immunosuppressants, and conventional cardiac treatment. This review focuses on the incidence, underlying mechanisms, clinical manifestations, diagnoses, and treatment strategies.

Evolving mechanisms and presentations of cardiovascular disease in people with HIV: implications for management

People with HIV (PWH) are at elevated risk for cardiovascular diseases (CVDs), including myocardial infarction, heart failure, and sudden cardiac death, among other CVD manifestations. Chronic immune dysregulation resulting in persistent inflammation is common among PWH, particularly those with sustained viremia and impaired CD4+ T cell recovery. This inflammatory milieu is a major contributor to CVDs among PWH, in concert with common comorbidities (such as dyslipidemia and smoking) and, to a lesser extent, off-target effects of antiretroviral therapy. In this review, we discuss the clinical and mechanistic evidence surrounding heightened CVD risks among PWH, implications for specific CVD manifestations, and practical guidance for management in the setting of evolving data.

Impaired balance between neutrophil extracellular trap formation and degradation by DNases in COVID-19 disease

BACKGROUND

Thrombo-inflammation and neutrophil extracellular traps (NETs) are exacerbated in severe cases of COVID-19, potentially contributing to disease exacerbation. However, the mechanisms underpinning this dysregulation remain elusive. We hypothesised that lower DNase activity may be associated with higher NETosis and clinical worsening in patients with COVID-19.

METHODS

Biological samples were obtained from hospitalized patients (15 severe, 37 critical at sampling) and 93 non-severe ambulatory cases. Our aims were to compare NET biomarkers, functional DNase levels, and explore mechanisms driving any imbalance concerning disease severity.

RESULTS

Functional DNase levels were diminished in the most severe patients, paralleling an imbalance between NET markers and DNase activity. DNase1 antigen levels were higher in ambulatory cases but lower in severe patients. DNase1L3 antigen levels remained consistent across subgroups, not rising alongside NET markers. DNASE1 polymorphisms correlated with reduced DNase1 antigen levels. Moreover, a quantitative deficiency in plasmacytoid dendritic cells (pDCs), which primarily express DNase1L3, was observed in critical patients. Analysis of public single-cell RNAseq data revealed reduced DNase1L3 expression in pDCs from severe COVID-19 patient.

CONCLUSION

Severe and critical COVID-19 cases exhibited an imbalance between NET and DNase functional activity and quantity. Early identification of NETosis imbalance could guide targeted therapies against thrombo-inflammation in COVID-19-related sepsis, such as DNase administration, to avert clinical deterioration.

TRIAL REGISTRATION

COVERAGE trial (NCT04356495) and COLCOV19-BX study (NCT04332016).

Neutrophil Extracellular DNA Traps in Response to Infection or Inflammation, and the Roles of Platelet Interactions

Neutrophils present the host's first line of defense against bacterial infections. These immune effector cells are mobilized rapidly to destroy invading pathogens by (a) reactive oxygen species (ROS)-mediated oxidative bursts and (b) via phagocytosis. In addition, their antimicrobial service is capped via a distinct cell death mechanism, by the release of their own decondensed nuclear DNA, supplemented with a variety of embedded proteins and enzymes. The extracellular DNA meshwork ensnares the pathogenic bacteria and neutralizes them. Such neutrophil extracellular DNA traps (NETs) have the potential to trigger a hemostatic response to pathogenic infections. The web-like chromatin serves as a prothrombotic scaffold for platelet adhesion and activation. What is less obvious is that platelets can also be involved during the initial release of NETs, forming heterotypic interactions with neutrophils and facilitating their responses to pathogens. Together, the platelet and neutrophil responses can effectively localize an infection until it is cleared. However, not all microbial infections are easily cleared. Certain pathogenic organisms may trigger dysregulated platelet-neutrophil interactions, with a potential to subsequently propagate thromboinflammatory processes. These may also include the release of some NETs. Therefore, in order to make rational intervention easier, further elucidation of platelet, neutrophil, and pathogen interactions is still needed.

Heparin Dose Intensity and Organ Support-Free Days in Patients Hospitalized for COVID-19

Background

Clinical trials suggest that therapeutic-dose heparin may prevent critical illness and vascular complications due to COVID-19, but knowledge gaps exist regarding the efficacy of therapeutic heparin including its comparative effect relative to intermediate-dose anticoagulation.

Objectives

The authors performed 2 complementary secondary analyses of a completed randomized clinical trial: 1) a prespecified per-protocol analysis; and 2) an exploratory dose-based analysis to compare the effect of therapeutic-dose heparin with low- and intermediate-dose heparin.

Methods

Patients who received initial anticoagulation dosed consistently with randomization were included. The primary outcome was organ support-free days (OSFDs), a combination of in-hospital death and days free of organ support through day 21.

Results

Among 2,860 participants, 1,761 (92.8%) noncritically ill and 857 (89.1%) critically ill patients were treated per-protocol. Among noncritically ill per-protocol patients, the posterior probability that therapeutic-dose heparin improved OSFDs as compared with usual care was 99.3% (median adjusted OR: 1.36; 95% credible interval [CrI]: 1.07-1.74). Therapeutic heparin had a high posterior probability of efficacy relative to both low- (94.6%; adjusted OR: 1.26; 95% CrI: 0.95-1.64) and intermediate- (99.8%; adjusted OR: 1.80; 95% CrI: 1.22-2.62) dose thromboprophylaxis. Among critically ill per-protocol patients, the posterior probability that therapeutic heparin improved outcomes was low.

Conclusions

Among noncritically ill patients hospitalized for COVID-19 who were randomized to and initially received therapeutic-dose anticoagulation, heparin, compared with usual care, was associated with improved OSFDs, a combination of in-hospital death and days free of organ support. Therapeutic heparin appeared superior to both low- and intermediate-dose thromboprophylaxis.

Superior Ophthalmic Vein Thrombosis Associated With Asymptomatic COVID-19 Infection

Superior ophthalmic vein thrombosis is a rare condition scarcely described in clinical literature with potentially severe consequences including permanent vision loss. This report details the case of a 70-year-old woman who presented with acute binocular horizontal diplopia, relative proptosis of the OD by 4 mm, and pain OD. On exam, visual acuity was 20/20 OD and 20/30 OS with full extraocular movements. CT revealed proptosis OD with a thrombosed superior ophthalmic varix. Evaluation for etiology of hypercoagulability was unremarkable, although the patient did have an asymptomatic COVID-19 infection 1 month prior. To the authors' knowledge, this is the first reported case of superior ophthalmic vein thrombosis secondary to an asymptomatic COVID-19 infection.

Myeloid cells in vascular dementia and Alzheimer's disease: Possible therapeutic targets?

Growing evidence supports the suggestion that the peripheral immune system plays a role in different pathologies associated with cognitive impairment, such as vascular dementia (VD) or Alzheimer's disease (AD). The aim of this review is to summarize, within the peripheral immune system, the implications of different types of myeloid cells in AD and VD, with a special focus on post-stroke cognitive impairment and dementia (PSCID). We will review the contributions of the myeloid lineage, from peripheral cells (neutrophils, platelets, monocytes and monocyte-derived macrophages) to central nervous system (CNS)-associated cells (perivascular macrophages and microglia). Finally, we will evaluate different potential strategies for pharmacological modulation of pathological processes mediated by myeloid cell subsets, with an emphasis on neutrophils, their interaction with platelets and the process of immunothrombosis that triggers neutrophil-dependent capillary stall and hypoperfusion, as possible effector mechanisms that may pave the way to novel therapeutic avenues to stop dementia, the epidemic of our time. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.

Phenotypes of Disseminated Intravascular Coagulation

Two phenotypes of disseminated intravascular coagulation (DIC) are systematically reviewed. DIC is classified into thrombotic and fibrinolytic phenotypes characterized by thrombosis and hemorrhage, respectively. Major pathology of DIC with thrombotic phenotype is the activation of coagulation, insufficient anticoagulation with endothelial injury, and plasminogen activator inhibitor-1-mediated inhibition of fibrinolysis, leading to microvascular fibrin thrombosis and organ dysfunction. DIC with fibrinolytic phenotype is defined as massive thrombin generation commonly observed in any type of DIC, combined with systemic pathologic hyperfibrinogenolysis caused by underlying disorder that results in severe bleeding due to excessive plasmin formation. Three major pathomechanisms of systemic hyperfibrinogenolysis have been considered: (1) acceleration of tissue-type plasminogen activator (t-PA) release from hypoxic endothelial cells and t-PA-rich storage pools, (2) enhancement of the conversion of plasminogen to plasmin due to specific proteins and receptors that are expressed on cancer cells and endothelial cells, and (3) alternative pathways of fibrinolysis. DIC with fibrinolytic phenotype can be diagnosed by DIC diagnosis followed by the recognition of systemic pathologic hyperfibrin(ogen)olysis. Low fibrinogen levels, high fibrinogen and fibrin degradation products (FDPs), and the FDP/D-dimer ratio are important for the diagnosis of systemic pathologic hyperfibrin(ogen)olysis. Currently, evidence-based treatment strategies for DIC with fibrinolytic phenotypes are lacking. Tranexamic acid appears to be one of the few methods to be effective in the treatment of systemic pathologic hyperfibrin(ogen)olysis. International cooperation for the elucidation of pathomechanisms, establishment of diagnostic criteria, and treatment strategies for DIC with fibrinolytic phenotype are urgent issues in the field of thrombosis and hemostasis.

DIA proteomics analysis reveals the mechanism of folic acid-induced acute kidney injury and the effects of icariin

The complexities of acute kidney injury (AKI), a multifaceted pathological occurrence, are not fully understood. At present, there is a lack of effective pharmaceutical treatments in clinical practice. Studies have shown that icariin has beneficial effects in models of acute kidney injury (AKI) caused by cisplatin and lipopolysaccharide (LPS). The aim is to explore the mechanisms that cause folic acid (FA)-induced AKI and examine the protective effects of icariin against this condition. To establish a mouse model of AKI, FA was administered via intraperitoneal injection. Icariin was used as the drug intervention. The model and the impact of drug intervention were assessed using measurements of renal function parameters, staining with hematoxylin and eosin, and Q-PCR. The analysis of protein expression changes in the control, model, and icariin treatment groups was conducted using proteomics. KEGG signaling pathway analysis indicates that differential expressed proteins are enriched in the component and coagulation cascades signaling pathway. Through protein-protein interaction network analysis, it was found that compared to the normal group, the expression of Fibrinogen and other proteins was significantly upregulated at the center of the protein interaction network in the model group. After drug treatment, the expression of these proteins was significantly downregulated. The validation experiment supports the above results. In conclusion, this study clarified the molecular mechanism of FA induced acute renal injury from the proteomics level, and provided target selection for AKI; At the same time, the mechanism of icariin in the treatment of AKI was analyzed from the proteomics level.

Mechanism and role of mitophagy in the development of severe infection

Mitochondria produce adenosine triphosphate and potentially contribute to proinflammatory responses and cell death. Mitophagy, as a conservative phenomenon, scavenges waste mitochondria and their components in the cell. Recent studies suggest that severe infections develop alongside mitochondrial dysfunction and mitophagy abnormalities. Restoring mitophagy protects against excessive inflammation and multiple organ failure in sepsis. Here, we review the normal mitophagy process, its interaction with invading microorganisms and the immune system, and summarize the mechanism of mitophagy dysfunction during severe infection. We highlight critical role of normal mitophagy in preventing severe infection.

Arterial Stiffness: From Basic Primers to Integrative Physiology

The elastic properties of conductance arteries are one of the most important hemodynamic functions in the body, and data continue to emerge regarding the importance of their dysfunction in vascular aging and a range of cardiovascular diseases. Here, we provide new insight into the integrative physiology of arterial stiffening and its clinical consequence. We also comprehensively review progress made on pathways/molecules that appear today as important basic determinants of arterial stiffness, particularly those mediating the vascular smooth muscle cell (VSMC) contractility, plasticity and stiffness. We focus on membrane and nuclear mechanotransduction, clearance function of the vascular wall, phenotypic switching of VSMCs, immunoinflammatory stimuli and epigenetic mechanisms. Finally, we discuss the most important advances of the latest clinical studies that revisit the classical therapeutic concepts of arterial stiffness and lead to a patient-by-patient strategy according to cardiovascular risk exposure and underlying disease.

Anti-thrombotic Effects Mediated by a Novel Dual-Target Peptide Inhibiting Both Platelet Aggregation and Thrombin Activity without Causing Bleeding

BACKGROUND

 Classical anticoagulants and antiplatelets are associated with high frequencies of bleeding complications or treatment failure when used as single agents. Thrombin plays an important role in the blood coagulation system. GP IIb/IIIa is the central receptor of platelets, which can recognize the Arg-Gly-Asp (RGD) sequence and activate platelets.

MATERIAL AND METHODS

 Molecular simulation and homology modeling were performed to design a novel dual-target anticoagulant short peptide (PTIP ). The activities of PTIP on coagulation and platelet in vitro were analyzed. The antithrombotic activity of PTIP was determined by pulmonary thromboembolism model, ferric chloride injury model and arteriovenous bypass thrombosis model. Bleeding effect and toxicity of PTIP were evaluated.

RESULTS

 We have constructed a novel dual-target peptide (PTIP) based on the direct thrombin inhibitor peptide (DTIP). PTIP was expressed at high levels in Pichia pastoris. PTIP interfered with thrombin-mediated coagulation and ADP-induced platelet aggregation in vitro. When injected intravenously or subcutaneously, PTIP showed potent and dose-dependent extension of aPTT and PT which were similar to DTIP; but only PTIP was capable of inhibiting platelet aggregation. PTIP (1.0 mg/kg) decelerated thrombosis formation in venous and arterial vessels induced by FeCl3 injury. PTIP (1.0 mg/kg) also prevented deep venous thrombosis and increased the survival rate associated with pulmonary thromboembolism. And PTIP effectively reduced thrombus length in arteriovenous bypass thrombosis model. Moreover, the antithrombotic dose of PTIP could not induce bleeding.

CONCLUSION

 These data establish that PTIP represents a novel antithrombotic agent whose effects involve both inhibition of platelet activation and reduction of fibrin generation. And PTIP not only can be used in venous thrombosis and arterial thrombosis, it can also replace the combined treatment of antiplatelet and anticoagulant drugs in thrombotic diseases.

Trauma-induced innate immune activation and disseminated intravascular coagulation

Dysregulated innate immunity participates in the pathomechanisms of disseminated intravascular coagulation (DIC) in trauma-induced coagulopathy. Accidental and regulated cell deaths and neutrophil extracellular traps release damage-associated molecular patterns (DAMPs), such as histones, nuclear and mitochondrial DNA, and high-mobility group box 1, into circulation immediately after trauma. DAMP-induced inflammation activation releases tissue factor-bearing procoagulant extracellular vesicles through gasdermin D-mediated pore formation and plasma membrane rupture by regulated cell death. DAMPs also evoke systemic inflammation, platelet, coagulation activation, and impaired fibrinolysis associated with endothelial injury, leading to the dysfunction of anticoagulation systems, which are the main pathophysiological mechanisms of DIC. All these processes induce systemic thrombin generation in vivo, not restricted to the injury sites immediately after trauma. Thrombin generation at the site of injury stops bleeding and maintains homeostasis. However, DIC associated with endothelial injury generates massive thrombin, enhancing protease-activated, receptor-mediated bidirectional interplays between inflammation and coagulation, aggravating the diverse actions of thrombin and disturbing homeostasis. Insufficiently regulated thrombin causes disseminated microvascular thrombosis, resulting in tissue hypoxia due to reduced oxygen delivery, and mitochondrial dysfunction due to DAMPs causes tissue dysoxia. In addition, DAMP-induced calcium influx and overload, as well as neutrophil activation, play a role in endothelial cell injury. Tissue hypoxia and cytotoxicity result in multiple organ dysfunction in DIC after trauma. Controls against dysregulated innate immunity evoking systemic inflammation, thrombin generation, and cytotoxicity are key issues in improving the prognosis of DIC in trauma-induced coagulopathy.

Role and intervention of PAD4 in NETs in acute respiratory distress syndrome

BACKGROUND

Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. Acute respiratory distress syndrome (ARDS) is a common sepsis-associated injury that can increase postoperative mortality but the mechanism is still unclear.

MAIN TEXT

The role of neutrophils in the pathophysiology of sepsis was deeply challenged after the discovery of NETosis, a process resulting in neutrophil extracellular traps (NETs) release. NETs can support thrombin generation and the concept of immunothrombosis has emerged as a new innate response to infection. Immunothrombosis leads to thrombosis in microvessels and supports immune cells together with specific thrombus-related molecules. ARDS is a common sepsis-associated organ injury. Immunothrombosis participates in thrombosis in pulmonary capillaries. Intervention regarding immunothrombosis in ARDS is a key scientific problem. PAD4 is the key enzyme regulating the NET skeleton protein histone H3 to citrulline histone to form NETs in immune thrombosis. This review summarizes NETosis and immunohaemostasis, ARDS and therapeutic opportunities targeting PAD4 via PAD4 inhibitors and lncRNAs potentially, providing future therapies.

CONCLUSIONS

We identified and summarized the fundamental definition of ARDS and the concept of immune thrombosis and its composition. NETs activation has become particularly relevant in the formation of immune thrombosis. The taskforce highlighted the intervention targets of PAD4, including noncoding RNAs, potentially providing future therapeutic targets to confront the high postoperative mortality of ARDS.

Design a dual-response two-photon fluorescent probe for simultaneous imaging of mitochondrial viscosity and peroxynitrite in a thrombosis model

BACKGROUND

Venous thromboembolism is a sudden cardiovascular disease that can lead to death, and its pathologic development is closely related to vascular viscosity and inflammation. However, direct evidence from in vivo is really scarce. The key limitation is that the combined probes cannot detect multiple markers simultaneously, which may lead to unreliable results. Therefore, to develop a single probe that can simultaneously monitor the variations of viscosity in the vascular microenvironment as well as inflammation level during venous thrombosis.

RESULTS

A dual-responsive two-photon fluorescent probe, Cou-ONOO, was designed and synthesized. Cou-ONOO provides a visualization tool for monitoring the viscosity of the vascular as well as the inflammatory marker ONOO‾ during thromboembolism via dual-channel simultaneous imaging. As a single probe that can recognize dual targets, Cou-ONOO effectively avoids the problems from unreliable results caused by complex synthesis and differences in intracellular localization, diffusion, and metabolism of different dyes as using combinatorial probes. Using Cou-ONOO, simultaneous imaging the variations of viscosity and ONOO‾at the cellular and tissue levels was successfully performed. In addition, Cou-ONOO also successfully visualized and tracked the viscosity of the vascular microenvironment and ONOO‾ during venous embolism in mice.

SIGNIFICANCE

Experimental results show that both viscosity and inflammation are abnormally overexpressed in the microenvironment at the thrombus site during venous thrombosis. An intuitive visualization tool to elucidate the variations of viscosity as well as inflammation level in the vascular microenvironment during thrombosis was provided, which will facilitate a better clinical understanding of the pathological process of thrombosis.

Lung Cancer Related Thrombosis (LCART): Focus on Immune Checkpoint Blockade

Cancer-associated thrombosis (CAT) is a common complication in lung cancer patients. Lung cancer confers an increased risk of thrombosis compared to other solid malignancies across all stages of the disease. Newer treatment agents, including checkpoint immunotherapy and targeted agents, may further increase the risk of CAT. Different risk-assessment models, such as the Khorana Risk Score, and newer approaches that incorporate genetic risk factors have been used in lung cancer patients to evaluate the risk of thrombosis. The management of CAT is based on the results of large prospective trials, which show similar benefits to low-molecular-weight heparins (LMWHs) and direct oral anticoagulants (DOACs) in ambulatory patients. The anticoagulation agent and duration of therapy should be personalized according to lung cancer stage and histology, the presence of driver mutations and use of antineoplastic therapy, including recent curative lung surgery, chemotherapy or immunotherapy. Treatment options should be evaluated in the context of the COVID-19 pandemic, which has been shown to impact the thrombotic risk in cancer patients. This review focuses on the epidemiology, pathophysiology, risk factors, novel predictive scores and management of CAT in patients with active lung cancer, with a focus on immune checkpoint inhibitors.

Vein wall thickness and severity of pulmonary involvement due to sars n-cov2 virus infection

BACKGROUND

An observational study involving patients recovered from COVID-19 was conducted in order to evaluate the presence/absence of vein wall thickness increasing, according to the severity of pulmonary involvement quantified with a CT-scoring system.

METHODS

The venous wall thickness (VWT) of 31 patients (23 males and 8 females) with COVID 19 previously admitted to Federico II University Hospital of Naples was evaluated through ultrasound measurement of the common femoral Vein 1 cm proximal to the saphenous-femoral junction and the popliteal Vein 1 cm distal to the confluence of gemellary veins. Measurements were taken with an automated tool to avoid human error. All patients were evaluated in the supine position. Patients were then stratified into two groups, VWT > 1 mm and VWT < 1 mm. Lung damage was assessed through thoracic High Resolution Computer Tomography and subsequently quantified using the scoring system set out by Chung et al. CEAP-C class was calculated for all patients.

RESULTS

The mean value of COVID score in VWT > 1 mm group was 7.4 (S.D. 4.83), whilst the mean value of the COVID score in the VWT < 1 mm group was 3.82 (S.D 3.34). These findings were determined to be statistically significant in a two-tie Student-T test. The linear regression test between VWT and Covid score values demonstrated a direct relationship between the two variables.

CONCLUSION

These results demonstrate a link between two different aspects of the pathological effects on the vessels during a SARS-COV 2 infection. As such a common primum movens can be hypothesized in both micro-thrombotic and inflammatory processes relating to COVID 19.

Development and validation of a risk model for intracardiac thrombosis in patients with dilated cardiomyopathy: a retrospective study

Intracardiac thrombosis is a severe complication in patients with non-ischemic dilated cardiomyopathy. This study aims to develop and validate an individualized nomogram to evaluate the risk of intracardiac thrombosis in patients with non-ischemic dilated cardiomyopathy. This retrospective study included patients diagnosed with dilated cardiomyopathy at first admission. Clinical baseline characteristics were acquired from electronic medical record systems. Multiple methods were applied to screen the key variables and generate multiple different variable combinations. Multivariable logistic regression was used to build the models, and the optimal model was chosen by comparing the discrimination. Then we checked the performance of the model in different thrombus subgroups. Finally, the model was presented using a nomogram and evaluated from the perspectives of discrimination, calibration, and clinical usefulness. Internal validation was performed by extracting different proportions of data for Bootstrapping. Ultimately, 564 eligible patients were enrolled, 67 of whom developed an intracardiac thrombosis. Risk factors included d-dimer, white blood cell count, high-sensitivity C-reactive protein, pulse pressure, history of stroke, hematocrit, and NT-proBNP in the optimal model. The model had good discrimination and calibration, and the area under the curve (AUC) was 0.833 (0.782-0.884), and the model's performance in each subgroup was stable. Clinical decision curve analysis showed that the model had clinical application value when the high-risk threshold was between 2% and 78%. The AUC of interval validation (30% and 70% data resampling) was 0.844 (0.765-0.924) and 0.833 (0.775-0.891), respectively. This novel intracardiac thrombosis nomogram could be conveniently applied to facilitate the individual intracardiac thrombosis risk assessment in patients with non-ischemic dilated cardiomyopathy.

Liver cirrhosis and complications from the perspective of dysbiosis

The gut-liver axis refers to the intimate relationship and rigorous interaction between the gut and the liver. The intestinal barrier's integrity is critical for maintaining liver homeostasis. The liver operates as a second firewall in this interaction, limiting the movement of potentially dangerous compounds from the gut and, as a result, contributing in barrier management. An increasing amount of evidence shows that increased intestinal permeability and subsequent bacterial translocation play a role in liver damage development. The major pathogenic causes in cirrhotic individuals include poor intestinal permeability, nutrition, and intestinal flora dysbiosis. Portal hypertension promotes intestinal permeability and bacterial translocation in advanced liver disease, increasing liver damage. Bacterial dysbiosis is closely related to the development of cirrhosis and its related complications. This article describes the potential mechanisms of dysbiosis in liver cirrhosis and related complications, such as spontaneous bacterial peritonitis, hepatorenal syndrome, portal vein thrombosis, hepatic encephalopathy, and hepatocellular carcinoma, using dysbiosis of the intestinal flora as an entry point.

Levels of peripheral blood routine, biochemical and coagulation parameters in patients with hemorrhagic fever with renal syndrome and their relationship with prognosis: an observational cohort study

BACKGROUND

Hantaan virus (HTNV), Seoul virus (SEOV) and Puumala virus (PUUV) are major serotypes of the Hantavirus, which can cause hemorrhagic fever with renal syndrome (HFRS). The pathophysiology of HFRS in humans is complex and the determinants associated with mortality, especially the coagulation and fibrinolysis disorders, are still not been fully elucidated. Severe patients usually manifest multiple complications except for acute kidney injury (AKI). The aim of this study was to observe the levels of peripheral blood routine, biochemical and coagulation parameters during the early stage, so as to find independent risk factors closely related to the prognosis, which may provide theoretical basis for targeted treatment and evaluation.

METHODS

A total of 395 HFRS patients from December 2015 to December 2018 were retrospectively enrolled. According to prognosis, they were divided into a survival group (n = 368) and a death group (n = 27). The peripheral blood routine, biochemical and coagulation parameters were compared between the two groups on admission. The relationship between the parameters mentioned above and prognosis was analyzed, and the dynamic changes of the coagulation and fibrinolysis parameters during the first week after admission were further observed.

RESULTS

In addition to AKI, liver injury was also common among the enrolled patients. Patients in the death group manifested higher levels of white blood cell counts (WBC) on admission. 27.30% (107/392) of the patients enrolled presented with disseminated intravascular coagulation (DIC) on admission and DIC is more common in the death group; The death patients manifested longer prothrombin time (PT) and activated partial thromboplastin time (APTT), higher D-dimer and fibrinogen degradation product (FDP), and lower levels of platelets (PLT) and fibrinogen (Fib) compared with those of the survival patients. The proportion of D-dimer and FDP abnormalities are higher than PT, APTT and Fib. Prolonged PT, low level of Fib and elevated total bilirubin (TBIL) on admission were considered as independent risk factors for prognosis (death).

CONCLUSIONS

Detection of PT, Fib and TBIL on admission is necessary, which might be benefit to early predicting prognosis. It is also important to pay attention to the dynamic coagulation disorders and hyperfibrinolysis during the early stage in the severe HFRS patients.

Nanoscaled Titanium Oxide Layer Provokes Quick Osseointegration on 3D-Printed Dental Implants: A Domino Effect Induced by Hydrophilic Surface

Three-dimensional printing is a revolutionary strategy to fabricate dental implants. Especially, 3D-printed dental implants modified with nanoscaled titanium oxide layer (H-SLM) have impressively shown quick osseointegration, but the accurate mechanism remains elusive. Herein, we unmask a domino effect that the hydrophilic surface of the H-SLM facilitates blood wetting, enhances the blood shear rate, promotes blood clotting, and changes clot features for quick osseointegration. Combining computational fluid dynamic simulation and biological verification, we find a blood shear rate during blood wetting of the hydrophilic H-SLM 1.2-fold higher than that of the raw 3D-printed implant, which activates blood clot formation. Blood clots formed on the hydrophilic H-SLM demonstrate anti-inflammatory and pro-osteogenesis effects, leading to a 1.5-fold higher bone-to-implant contact and a 1.8-fold higher mechanical anchorage at the early stage of osseointegration. This mechanism deepens current knowledge between osseointegration speed and implant surface characteristics, which is instructive in surface nanoscaled modification of multiple 3D-printed intrabony implants.

Identification of potential biological processes and key genes in diabetes-related stroke through weighted gene co-expression network analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) is an established risk factor for acute ischemic stroke (AIS). Although there are reports on the correlation of diabetes and stroke, data on its pathogenesis is limited. This study aimed to explore the underlying biological mechanisms and promising intervention targets of diabetes-related stroke.

METHODS

Diabetes-related datasets (GSE38642 and GSE44035) and stroke-related datasets (GSE16561 and GSE22255) were obtained from the Gene Expression omnibus (GEO) database. The key modules for stroke and diabetes were identified by weight gene co-expression network analysis (WGCNA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes Genomes (KEGG) analyses were employed in the key module. Genes in stroke- and diabetes-related key modules were intersected to obtain common genes for T2DM-related stroke. In order to discover the key genes in T2DM-related stroke, the Cytoscape and protein-protein interaction (PPI) network were constructed. The key genes were functionally annotated in the Reactome database.

RESULTS

By intersecting the diabetes- and stroke-related crucial modules, 24 common genes for T2DM-related stroke were identified. Metascape showed that neutrophil extracellular trap formation was primarily enriched. The hub gene was granulin precursor (GRN), which had the highest connectivity among the common genes. In addition, functional enrichment analysis indicated that GRN was involved in neutrophil degranulation, thus regulating neutrophil extracellular trap formation.

CONCLUSIONS

This study firstly revealed that neutrophil extracellular trap formation may represent the common biological processes of diabetes and stroke, and GRN may be potential intervention targets for T2DM-related stroke.

Value function assessment to different RL algorithms for heparin treatment policy of patients with sepsis in ICU

Heparin is a critical aspect of managing sepsis after abdominal surgery, which can improve microcirculation, protect organ function, and reduce mortality. However, there is no clinical evidence to support decision-making for heparin dosage. This paper proposes a model called SOFA-MDP, which utilizes SOFA scores as states of MDP, to investigate clinic policies. Different algorithms provide different value functions, making it challenging to determine which value function is more reliable. Due to ethical restrictions, we cannot test all policies on patients. To address this issue, we proposed two value function assessment methods: action similarity rate and relative gain. We experimented with heparin treatment policies for sepsis patients after abdominal surgery using MIMIC-IV. In the experiments, TD(0) shows the most reliable performance. Using the action similarity rate and relative gain to assess AI policy from TD(0), the agreement rates between AI policy and "good" physician's actual treatment are 64.6% and 73.2%, while the agreement rates between AI policy and "bad" physician's actual treatment are 44.1% and 35.8%, the gaps are 20.5% and 37.4%, respectively. External validation using action similarity rate and relative gain based on eICU resulted in agreement rates of 61.5% and 69.1% with the "good" physician's treatment, and 45.2% and 38.3% with the "bad" physician's treatment, with gaps of 16.3% and 30.8%, respectively. In conclusion, the model provides instructive support for clinical decisions, and the evaluation methods accurately distinguish reliable and unreasonable outcomes.

Thromboinflammation in acute injury: infections, heatstroke, and trauma

Tissue microcirculation is essential for the maintenance of organ homeostasis. Following acute infections, activation of coagulation and inflammation, which are critical interconnected responses, lead to thromboinflammation and microthrombosis, thereby contributing to multiorgan dysfunction. Sepsis is the most common underlying disease and has been extensively studied. However, the COVID-19 pandemic further illustrated the pathomechanisms of diseases in which thromboinflammation plays a critical role. During thromboinflammation, injury to monocytes, neutrophils, platelets, and endothelial cells, along with coagulation and complement activation, was further characterized. Thrombin is pivotal in orchestrating thrombosis and inflammation and has long been considered a potential therapeutic target in sepsis. Although thromboprophylaxis for venous thromboembolism with heparins is part of standard management for COVID-19, it also potentially attenuates organ dysfunction due to thrombotic sequela. In contrast, the effectiveness of anticoagulation with heparin, antithrombin, or thrombomodulin to reduce mortality has not conclusively been proven in sepsis. Nonetheless, thromboinflammation has also been reported as an important pathophysiologic mechanism in other critical illnesses, including heatstroke, trauma, and ischemia/reperfusion injury, and may provide a potential therapeutic target for future clinical studies.

The neurobiology of SARS-CoV-2 infection

Worldwide, over 694 million people have been infected with SARS-CoV-2, with an estimated 55-60% of those infected developing COVID-19. Since the beginning of the pandemic in December 2019, different variants of concern have appeared and continue to occur. With the emergence of different variants, an increasing rate of vaccination and previous infections, the acute neurological symptomatology of COVID-19 changed. Moreover, 10-45% of individuals with a history of SARS-CoV-2 infection experience symptoms even 3 months after disease onset, a condition that has been defined as 'post-COVID-19' by the World Health Organization and that occurs independently of the virus variant. The pathomechanisms of COVID-19-related neurological complaints have become clearer during the past 3 years. To date, there is no overt - that is, truly convincing - evidence for SARS-CoV-2 particles in the brain. In this Review, we put special emphasis on discussing the  methodological difficulties of viral detection in CNS tissue and discuss immune-based (systemic and central) effects contributing to COVID-19-related CNS affection. We sequentially review the reported changes to CNS cells in COVID-19, starting with the blood-brain barrier and blood-cerebrospinal fluid barrier - as systemic factors from the periphery appear to primarily influence barriers and conduits - before we describe changes in brain parenchymal cells, including microglia, astrocytes, neurons and oligodendrocytes as well as cerebral lymphocytes. These findings are critical to understanding CNS affection in acute COVID-19 and post-COVID-19 in order to translate these findings into treatment options, which are still very limited.

Immunothrombosis and its underlying biological mechanisms

The evolutionary conserved link between coagulation and innate immunity is a biological process characterized by the thrombosis formation stimulus of immune cells and specific thrombosis-related molecules. In physiological settings, the relationship between the immune system and thrombosis facilitates the recognition of pathogens and damaged cells and inhibits pathogen proliferation. However, when deregulated, the interplay between hemostasis and innate immunity becomes a pathological process named immunothrombosis, which is at the basis of several infectious and inflammation-related thrombotic disorders, including coronavirus disease 2019 (COVID-19). In advanced stages, alterations in both coagulation and immune cell function due to extreme inflammation lead to an increase in blood coagulability, with high rates of thrombosis and mortality. Therefore, understanding underlying mechanisms in immunothrombosis has become decisive for the development of more efficient therapies to treat and prevent thrombosis in COVID-19 and in other thrombotic disorders. In this review, we outline the existing knowledge on the molecular and cellular processes involved in immunothrombosis, focusing on the role of neutrophil extracellular traps (NETs), platelets and the coagulation pathway. We also describe how the deregulation of hemostasis is associated with pathological conditions and can significantly aggravate a patient's condition, using COVID-19 as a clinical model.