Microvascular Thrombus Research Articles

Coronary No-Reflow after Primary Percutaneous Coronary Intervention

Coronary no-reflow is a significant complication following primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction. This phenomenon involves inadequate myocardial perfusion despite successful vessel recanalization, attributed to factors such as microvascular injury, inflammation, thrombus embolization, and vasospasm. Effective management strategies include pharmacological agents, mechanical interventions, and optimized antithrombotic therapy. Prompt diagnosis and treatment are essential to enhance patient outcomes and reduce adverse effects associated with this condition.

In-Situ Thrombosis Post Primary Percutaneous Coronary Intervention and Possible Management

Background: Several intracoronary agents have been used by interventional cardiologists, in context of PCI iatrogenic thrombosis. Recently the use of low-dose fibrinolysis at the time of the primary PCI has gained popularity as a new strategy to improve post-procedural coronary flow. Conclusion: Using low-dose fibrinolytic therapy at the time of primary PCI might play a vital role in minimizing the risk of microvascular thrombus.

Interferons prime the endothelium for toll-like receptor–mediated thrombin generation

BackgroundRespiratory infection is associated with microvascular thrombus formation and marked elevation in cytokine levels. The role of cytokines elaborated by the pulmonary epithelium in thrombotic responses is poorly understood. ObjectivesOur goal was to identify cytokines of pulmonary epithelial cell origin that enhance thrombin generation in the endothelium at concentrations equal to or less than those found in the circulation during infection. MethodsWe screened multiple cytokines produced by the pulmonary epithelium for the ability to enhance toll-like receptor (TLR)–mediated endothelial thrombin generation. Effects of cytokines on tissue factor and thrombomodulin expression, cytokine selectivity for different TLRs, and prothrombotic activity of endogenous cytokines in conditioned medium from pulmonary human epithelial cells were evaluated. ResultsMIP-1β, MCP-1, IL-10, IL-6, IL-1β, TNFα, IFNα, IFNβ, and IFNγ were tested for their ability to enhance TLR3-mediated thrombin generation on endothelial cells. Only interferons (IFNs) and TNFα promoted TLR3-mediated thrombin generation at levels that circulate during infection. IFNs robustly enhanced tissue factor expression when used in conjunction with TLR agonists and reduced thrombomodulin expression in the endothelium independently of TLRs. IFNα, which is typically elevated with viral infection, only synergized with TLR3 agonists mimicking viral pathogen-associated molecular patterns. In contrast, IFNγ, which is typically observed in bacterial infection, synergized more effectively with TLR4 agonists released by bacteria. Conditioned media from inflamed pulmonary epithelial cells primed the endothelium for TLR-mediated thrombin generation. Anti-IFN type I antibodies blocked this effect, indicating that endogenous IFNs prime the endothelium for TLR-mediated thrombin generation. ConclusionIFNs elaborated by the pulmonary epithelium are necessary and sufficient to enhance TLR-mediated thrombin generation.

Endothelial ADAM10 utilization defines a molecular pathway of vascular injury in mice with bacterial sepsis.

The endothelium plays a critical role in the host response to infection and has been a focus of investigation in sepsis. While it is appreciated that intravascular thrombus formation, severe inflammation, and loss of endothelial integrity impair tissue oxygenation during sepsis, the precise molecular mechanisms that lead to endothelial injury remain poorly understood. We demonstrate here that endothelial ADAM10 was essential for the pathogenesis of Staphylococcus aureus sepsis, contributing to α-toxin-mediated (Hla-mediated) microvascular thrombus formation and lethality. As ADAM10 is essential for endothelial development and homeostasis, we examined whether other major human sepsis pathogens also rely on ADAM10-dependent pathways in pathogenesis. Mice harboring an endothelium-specific knockout of ADAM10 were protected against lethal Pseudomonas aeruginosa and Streptococcus pneumoniae sepsis, yet remained fully susceptible to group B streptococci and Candida albicans sepsis. These studies illustrate a previously unknown role for ADAM10 in sepsis-associated endothelial injury and suggest that understanding pathogen-specific divergent host pathways in sepsis may enable more precise targeting of disease.

Serial Case: Infarct Stroke In Covid 19 Patients

Introduction: SARS-CoV-2 has been reported to cause various neurological symptoms including stroke. SARS-CoV-2 infection causes the release of cytokines, proinflammatory chemokines, immune system activation, coagulopathy, endothelium, vasculitis, hypoxia, renin-angiotensin system imbalance, and cardiovascular complications, all of which can contribute to stroke. Purpose: Describe the incidence of stroke with different conditions in COVID 19 Cases: There were two cases of stroke infarct in a COVID-19 patient who was admitted to our hospital. Both were treated with a diagnosis of stroke infarct with previous COVID-19 symptoms, the results of laboratory examinations revealed an increase in inflammatory markers in both patients and had been given appropriate treatment according to each patient's condition. But at the end of the treatment one patient died and the other patient went home with clinical improvement. Discussion: The incidence of stroke infarct in this case is thought to be due to several factors, namely the presence of comorbidities in the patient, microvascular thrombus due to the formation of neutrophil extracellular traps (NET), activation of complement which causes thrombogenesis and vasculopathy, formation of antiphospholipid antibodies so that protein c is reduced, the formation of microparticles causes platelet hyperactivation. and increased tissue factor (TF) resulting in hypercoagulation. Adequate therapy in controlling inflammation due to COVID 19 has shown clinical improvement in stroke infarct patients. Conclusion: There are 2 cases of stroke infarction in patients with covid 19 who have comorbidities. The first case with COVID advanced stages experienced a worsening of the condition despite being given appropriate therapy. The second case with COVID middle stages experienced an improvement in the condition after the viral inflammatory factors were controlled and the comorbidity was well controlled.

Combination regimens containing daratumumab for initial diagnosed acquired thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura (TTP) is a rare and life-threatening thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, severe thrombocytopenia, and organ ischemia associated with disseminated microvascular platelet-rich thrombus. Before the introduction of plasma therapy, acute TTP was almost universally fatal, which improved survival from < 10 to 80-90%. However, patients who survived an acute attack were at high risk for recurrence and long-term morbidity. It was reported that daratumumab can eradicate persistent ADAMTS13-inhibiting autoantibodies and restore ADAMTS13 activity in two patients with relapsed immune-mediated TTP without associated adverse drug reactions. Here we report a case series of patients with initial diagnosed acquired TTP treated with combination regimens containing daratumumab. All the patients achieved clinical response after the initial treatment. Three patients achieved clinical remission, one patient relapsed and one patient suffered an exacerbation during follow-up. The two patients were retreated with glucocorticoids, plasma exchange combined with daratumumab, and clinical remission was achieved again. Combination of daratumumab in the treatment of initial diagnosed acquired thrombotic thrombocytopenic purpura can rapidly restore ADAMST13 activity and turn negative for ADAMST13 inhibitors, resulting in long-term remission in patients.

Complications in microsurgical breast reconstruction: thrombosis prevention and management

Breast reconstruction is one of the largest components of plastic and reconstructive surgery. Autologous free flap breast reconstruction continues to grow due to exceptionally high flap success rates. It provides patients with a durable and natural reconstruction with high patient satisfaction. A patent microvascular anastomosis is a key component to a successful autologous free flap breast reconstruction. Thrombus within the vascular anastomosis or the distal flap microcirculation is the most common cause of flap failure. This review aims to discuss microsurgical techniques including atraumatic handling of vessels, appropriate magnification, suture styles, anastomotic techniques, recipient vessel selection, the role of anticoagulation and antiplatelet therapy used to minimize the risk of thrombotic events. When microvascular thrombus occurs, early reoperation and reperfusion is imperative to flap survival. This review will discuss specific maneuvers and intraoperative interventions to maximize flap salvage.

Pathological Lung Patterns of COVID-19 and its Clinical Correlation to Disease Severity.

Coronavirus disease-2019 (COVID-19) infection can result in pulmonary complications ranging from mild illness to severe life-threatening disease. There are limited studies correlating the association between the clinical course of COVID-19 and histopathological findings. This study aimed to examine the postmortem histopathological changes in lung tissue of COVID-19-positive patients and to correlate those changes with disease severity. This prospective observational study was conducted in adult COVID-19-positive patients. Postmortem core needle biopsy (CNB) of the lung was done using ultrasonography guidance within 1 hour of death. Histopathological analyses were performed by two expert pulmonary pathologists. The demographic and clinical data of the patients were recorded to correlate them with histopathological findings. In total, 48 patients were assessed for inclusion, and 21 patient relatives consented for the study. The median duration of illness was 21 (range 9-38) days, the predominant histopathological finding was diffuse alveolar damage (DAD) in most patients (19/21), followed by pneumonia (13/21). Exudative, intermediate, and advanced DAD patterns were seen in 9.5%, 52.4%, and 28.6% of cases, respectively. Advanced DAD was associated with a longer duration of disease. The pneumonia findings were associated with positive respiratory and blood cultures. The microvascular thrombus was seen only in one patient. The predominant pathological findings in our patients were DAD and pneumonia. The DAD type correlated with the duration of illness, and we attributed pneumonia findings to secondary infection. The incidence of microvascular thrombi was low, and it might reflect the effect of treatment with anticoagulation. Maddani SS, Rao R, Deepa HC, Noronha AK, Chaudhuri S, Vishwas P. Pathological Lung Patterns of COVID-19 and its Clinical Correlation to Disease Severity. Indian J Crit Care Med 2022;26(12):1285-1292.

Intrapulmonary shunt and alveolar dead space in a cohort of patients with acute COVID-19 pneumonitis and early recovery.

Pathological evidence suggests that coronavirus disease 2019 (COVID-19) pulmonary infection involves both alveolar damage (causing shunt) and diffuse microvascular thrombus formation (causing alveolar dead space). We propose that measuring respiratory gas exchange enables detection and quantification of these abnormalities. We aimed to measure shunt and alveolar dead space in moderate COVID-19 during acute illness and recovery. We studied 30 patients (22 males; mean±sd age 49.9±13.5 years) 3-15 days from symptom onset and again during recovery, 55±10 days later (n=17). Arterial blood (breathing ambient air) was collected while exhaled oxygen and carbon dioxide concentrations were measured, yielding alveolar-arterial differences for each gas (P A-aO2 and P a-ACO2 , respectively) from which shunt and alveolar dead space were computed. For acute COVID-19 patients, group mean (range) for P A-aO2 was 41.4 (-3.5-69.3) mmHg and for P a-ACO2 was 6.0 (-2.3-13.4) mmHg. Both shunt (% cardiac output) at 10.4% (0-22.0%) and alveolar dead space (% tidal volume) at 14.9% (0-32.3%) were elevated (normal: <5% and <10%, respectively), but not correlated (p=0.27). At recovery, shunt was 2.4% (0-6.1%) and alveolar dead space was 8.5% (0-22.4%) (both p<0.05 versus acute). Shunt was marginally elevated for two patients; however, five patients (30%) had elevated alveolar dead space. We speculate impaired pulmonary gas exchange in early COVID-19 pneumonitis arises from two concurrent, independent and variable processes (alveolar filling and pulmonary vascular obstruction). For most patients these resolve within weeks; however, high alveolar dead space in ∼30% of recovered patients suggests persistent pulmonary vascular pathology.

Promoting the Resolution of Thromboinflammation

BackgroundThrombosis is viewed as a multi‐step, multi‐cellular process driven by inflammatory stimuli and leukocyte (e.g. neutrophil) activation, and is a major pathophysiological contributor of stroke. Accumulating data supports the hypothesis that anti‐inflammatory therapies may limit thrombosis and anti‐thrombotic therapies may reduce vascular inflammation. One such target is the anti‐inflammatory and pro‐resolving endogenous mediator Annexin A1 (AnxA1). The development of therapies that temper inflammation and enhance resolution offer potential therapeutic strategies for the treatment and management of stroke and other thromboinflammatory diseases. Here we sought to comprehensively elucidate the functional significance of targeting the AnxA1/Fpr2/ALX pathway in thrombosis.Material and MethodsWe used a well‐characterized light/dye thrombosis model, coupled with pharmacological and genetic approaches. Male and female adult wild type (WT, C57/BL6) or AnxA1 knock‐out (AnxA1‐/‐) mice were used. Fluorescence intravital microscopy (IVM) was used to monitor cerebral thrombosis, along with flow cytometry. Mice were treated with AnxA1 (1 µg/mouse) or saline vehicle 20 minutes before the onset of cerebral thrombus formation. Thrombogenesis and blood flow cessation times were quantified. (All animal experiments were approved by relevant institutional animal welfare panels and were conducted in accordance with the American Association for Accreditation of Laboratory Animal Care guidelines and complied with ARRIVE [Animal Research: Reporting In Vivo Experiments]).ResultsIVM revealed that AnxA1 treatment was able to prolong blood flow cessation times in both cerebral arterioles and venules, via regulation of the key inflammation resolution receptor: FPR2/ALX, as evidenced by the co‐administration of the FPR2/ALX antagonist WRW4. Using AnxA1−/− mice, we found that a deletion of AnxA1 impacts thrombosis as shown by the accelerated cerebral microvascular thrombus formation (decrease in blood flow cessation time) observed in both arterioles and venules of these mice compared to their WT counterparts (arterioles: 17.9 ± 2.3 vs 33.2 ± 1.9 min and venules: 13.2 ± 2.4 vs 20.9 ± 2.2 min. p&lt;0.05). Furthermore, we found that in an inflammatory backdrop (induced by the administration of lipopolysaccharide [LPS]), AnxA1 treatment was able to suppress both platelet αIIbβ3 and P‐selectin expression.ConclusionHerein, we found a previously unknown phenomenon that the anti‐inflammatory protein AnxA1 can modify a thromboinflammatory environment to promote resolution. These findings have far‐reaching applicability for drug discovery programs focused on resolution biologics targeting thromboinflammatory diseases such as cardiovascular disease and stroke.

Smurf2 suppresses the metastasis of hepatocellular carcinoma via ubiquitin degradation of Smad2.

PurposeSmurf2, one of C2-WW-HECT domain E3 ubiquitin ligases, is closely related to the development and progression in different cancer types, including hepatocellular carcinoma (HCC). This study aims to illustrate the expression and molecular mechanism of Smurf2 in regulating the progression of HCC.MethodsThe expression of Smurf2 in human HCC and adjacent non-tumor liver specimens was detected using tissue microarray studies from 220 HCC patients who underwent curative resection. The relationships of Smurf2 and HCC progression and survival were analyzed using the chi-square test, Kaplan–Meier analysis, and Cox proportional hazards model. For Smurf2 was low expression in HCC cell lines, Smurf2 overexpression cell lines were established. The effect of Smurf2 on cell proliferation and migration was detected by Cell Counting Kit-8 and colony formation assay, and the epithelial–mesenchymal transition (EMT) markers and its transcription factors were tested by immunoblotting. The interaction and ubiquitination of Smad2 by Smurf2 were detected by co-immunoprecipitation and immunoprecipitation assay. Finally, the effect of Smurf2 on HCC was verified using the mouse lung metastasis model.ResultsSmurf2 was downregulated in HCC tissues compared to that of corresponding non-tumor liver specimens. The low expression of Smurf2 in HCC was significantly associated with macrovascular or microvascular tumor thrombus and the impairment of overall survival and disease-free survival. In vitro and in vivo analysis showed that Smurf2 overexpression decreased the EMT potential of HCC cells by promoting the ubiquitination of Smad2 via the proteasome-dependent degradation pathway.ConclusionThe expression of Smurf2 was downregulated in HCC specimens and affected the survival of patients. Smurf2 inhibited the EMT of HCC by enhancing Smad2 ubiquitin-dependent proteasome degradation.

P-Selectin Deficiency Reduces Acute Vascular Complications but Not Chronic Organ Damage in Sickle Cell Mice

P-selectin (Psel) is an adhesion molecule expressed on platelets and endothelial cells, which interacts with its ligand PSGL-1 on leukocytes and a PSGL-1-like molecule on sickle red blood cells (RBCs). Psel mediates the formation of the multicellular aggregates that promote vaso-occlusive crisis (VOC) and acute painful episodes in sickle cell disease (SCD). Crizanlizumab, a monoclonal antibody blocking Psel, reduces the frequency of VOC in SCD patients. In SCD mice, Psel contributes to heme-induced microvascular stasis, and thrombus and platelet-neutrophil aggregate formation in the lung and liver. Unexpectedly, Psel deficiency promotes liver senescence in a mouse model of SCD, suggesting a possible detrimental effect of Psel inhibition. In this study, we further investigated the long-term effects of Psel deficiency on thromboinflammation and end-organ damage in murine SCD.We used Townes wild type (AA) and sickle (SS) mice (n=12-27) that either express Psel (Psel +/+) or lack Psel (Psel -/-) at 11-12 months of age. Kidney damage was evaluated by histology and urine analysis. Heart function was determined using echocardiography. Complete blood counts and plasma biomarkers of thrombin generation (thrombin anti-thrombin [TAT] complexes) and inflammation (interleukin [IL]-6) were also analyzed. In addition, in a pilot experiment, we analyzed the effect of Psel deficiency on experimental venous thrombosis in SS mice.SS Psel +/+ mice exhibited renal damage, urinary concentrating defect, and reduced creatinine clearance, which was not improved in SS Psel -/- mice. Psel deficiency attenuated glomerular (GLM) congestion (0.17±0.05 vs 0.39±0.06, p<0.05) but failed to prevent GLM injury, as evidenced by similar extent of GLM sclerosis, hypertrophy and podocyte loss in SS mice. Interestingly, only SS P-sel -/- mice presented withdistinct differences in GLM structure, demonstrated by extensive hypercellularity, mesangial expansion and mesangiolysis. We also observed tubular injury concomitant with brush border loss and interstitial fibrosis in SS mice, regardless of Psel expression. Additionally, there was a significant reduction in CD3 + T cells (5.0±1.2 vs 9.5±1.6 cells/field; p<0.05) and macrophages (1.0±0.1 vs 1.6±0.2 % of area; p<0.05) infiltration in the kidney cortex of SS Psel -/- compared to SS Psel +/+ mice. This corresponded to a greater renal iron accumulation in SS Psel -/- mice (59.9±4.2 vs 48.2±3.2 Mpix/μm; p<0.05).We observed cardiac hypertrophy (elevated heart weight to tibia length ratio) in SS mice, regardless of Psel expression. Echocardiography of left ventricle (LV) revealed that SS mice had increased LV mass and LV internal diameter with no change in ejection fraction or fractional shortening compared to AA mice. None of these parameters were affected by Psel expression. Furthermore, hypertrophy observed in other organs (kidney, liver, lung and spleen) of SS Psel +/+ mice was also not affected by Psel deficiency.Consistent with previous studies, SS Psel +/+ mice had elevated plasma levels of TAT and IL-6 compared to AA Psel +/+ mice. Psel deficiency significantly reduced IL-6 (47±15 vs 20±10 ng/mL, P<0.05), but had no effect on elevated plasma TAT levels in SS mice. Despite the lack of effect of Psel deficiency on systemic thrombin generation in SS mice, femoral vein thrombi formed after electrolytic injury exhibited a strong trend in reduced fibrin and platelet content compared to SS Psel+/+ mice (n=5 per group).As expected, SS Psel +/+ mice exhibited anemia as shown by reduced RBC number, hemoglobin (Hb) and hematocrit (Hct) compared to AA Psel +/+ animals. Interestingly, these parameters were further decreased in SS Psel -/- mice (p<0.01 for all); RBC (5.6±0.2 vs 4.4±0.4 x 10 6/mL), Hg (6.7±0.2 vs 5.7±0.2 g/dL) and Hct (25.1±1.1 vs 19.7±1.1%). This was accompanied by a significant increase in mean corpuscular Hb concentration (26.9±0.5 vs 29.2±0.5 g/dL p< 0.01) but no changes in RBC mean corpuscular volume in SS Psel -/-mice compared to SS Psel +/+ mice.Our data suggest that despite improving acute vascular pathologies, including VOC and thromboinflammation, long term deficiency of Psel does not prevent end-organ damage. If fact, it may contribute to organ dysfunction and enhanced anemia. More mechanistic studies are needed to better understand the long-term effects of anti-Psel treatment in SCD patients. DisclosuresReeves: Incyte Corporation: Honoraria; Takeda: Honoraria; Bristol-Myers Squibb: Speakers Bureau; Pharma Essentia: Consultancy, Honoraria. Sundd: CSL Behring Inc: Research Funding; Bayer: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding.

The Resolution Mediator Annexin A1 Affords Protection Against Thromboinflammation

Stroke is a leading cause of death and disability worldwide, with the majority (~85 %) being ischemic in origin. Age is the most important non-modifiable risk factor for acute ischemic stroke (AIS). While inflammation with ageing is a well-known complication of AIS, a new model is emerging in which ageing-associated thrombosis is being viewed as a multi-step, multi-cellular process driven by inflammatory stimuli and recruitment/activation of leukocytes. The ideal outcome of inflammation is resolution, an active process involving specific endogenous mediators (e.g. annexin A1 [AnxA1]) and related pathways (e.g. formyl peptide receptor-2 [Fpr2/ALX] pathway).[1,2] The development of therapies that temper inflammation and enhance resolution offer potential therapeutic strategies for the treatment and management of thromboinflammation associated with AIS. We have shown that the AnxA1 mimetic peptide AnxA1 Ac2-26 ameliorates thrombotic responses in thromboinflammatory conditions such as Sickle Cell Disease,[3] however, the role that AnxA1 plays in age-related thrombosis is currently unknown. Here we sought to comprehensively elucidate the functional significance of targeting the AnxA1/Fpr2/ALX pathway in age-related thrombosis.Initially, to evaluate the role of AnxA1, thrombosis in cerebral vessels was induced using the light/dye thrombosis model.[2] Male and female adult (10-14 weeks) and ageing (18-24 months) wild type (WT, C57/BL6) or AnxA1 knock-out (AnxA1 -/-) mice were used. WT mice received AnxA1 (1 µg/mouse), or saline vehicle injected 20 min before the onset of thrombus formation in cerebral pial vessels. Thrombogenesis and blood flow cessation times were quantified. AnxA1 treatment was able to prolong blood flow cessation times in both cerebral arterioles and venules, an effect which was more pronounced in ageing mice (p<0.05) via regulation of the FPR2/ALX-pathway.Next, to investigate the mechanism of action of AnxA1 in an inflammatory backdrop (i.e. lipopolysaccharide [LPS]), the effect of AnxA1 on platelet P‐selectin and αIIbβ3 receptor expression, following stimulation with the GPVI collagen receptor agonist convulxin (CVX), was performed. CVX treatment increased platelet activation, which was suppressed by AnxA1 co‐administration (100 ng. p<0.05). CVX+LPS increased platelet αIIbβ3 or P‐selectin levels, which were inhibited by the administration of AnxA1.Finally, to determine whether a deletion of AnxA1 impacts thrombosis, we performed the light/dye thrombosis model in AnxA1 −/− mice. These mice displayed accelerated cerebral microvascular thrombus formation (decrease in blood flow cessation time) compared to WT mice in both arterioles and venules (arterioles: 17.9 ± 2.3 vs 33.2 ± 1.9 min and venules: 13.2 ± 2.4 vs 20.9 ± 2.2 min. p<0.05).In conclusion, these results demonstrate the ability of AnxA1 to modify the thromboinflammatory environment, including reducing platelet activation under inflammatory conditions via GPVI. Collectively, these data show the importance of the AnxA1/Fpr2/ALX system in effecting the resolution of cerebral thromboinflammation in ageing and may provide a novel therapeutic strategy for AIS and other thromboinflammatory conditions. DisclosuresNo relevant conflicts of interest to declare.

Analysis of microvascular thrombus mechanobiology with a novel particle-based model

Platelet accumulation at the site of a vascular injury is regulated by soluble platelet agonists, which induce various types of platelet responses, including integrin activation and granule secretion. The interplay between local biochemical cues, mechanical interactions between platelets and macroscopic thrombus dynamics is poorly understood.Here we describe a novel computational model of microvascular clot formation for the detailed analysis of thrombus mechanics. We adopt a previously developed two-dimensional particle-based model focused on the thrombus shell formation and revise it to introduce the platelet agonists. Blood flow is simulated via a computational fluid dynamics approach. In order to model soluble platelet activators, we apply Langevin dynamics to a large number of non-dimensional virtual particles. Taking advantage of the available data on platelet dense granule secretion kinetics, we model platelet degranulation as a stochastic agonist-dependent process.The new model qualitatively reproduces the enhanced thrombus formation due to dense granule secretion, in line with in vivo findings, and provides a mechanism for the thrombin confinement at the early stages of clot formation. Our calculations also predict that the release of platelet dense granules results in the additional mechanical stabilization of the inner layers of thrombus. Distribution of the inter-platelet forces throughout the aggregate reveals multiple weak spots in the outer regions of a thrombus, which are expected to result in the mechanical disruptions at the later stages of clot formation.

Study on the prognostic value of preoperative anti hepatitis B virus therapy in patients with hepatocellular carcinoma complicated with microvascular tumor thrombus and establishment of survival prediction model

Objective: To explored the effect of preoperative antiviral therapy on the prognosis of microvascular tumor thrombi patients, and to established a prognostic prediction model for these patients after radical resection of liver cancer. Methods: The clinicopathological and survival data of hepatocellular carcinoma patients with microvascular tumor thrombus who underwent radical resection in the Third Affiliated Hospital of Sun Yat-sen University from January 1, 2013 to December 31, 2015 were retrospectively collected. Kaplan-Meier method was used to calculate the survival curve, and log-rank test was used to compare the prognosis of patients with and without antiviral treatment before operation. Univariate and multivariate Cox proportional hazard regression model was used to screen predictive factors. R software was used to make predictive nomogram, and discrimination and calibration degree were used to evaluate the prediction model. Results: Among all 153 patients, 22 were female and 131 were male, aged (51.3±11.7) years. The preoperative antiviral therapy significantly improved overall survival and recurrence-free survival (χ2=41.423, 54.389; both P<0.001). According to the results of multivariate and regression analysis, preoperative antiviral therapy (HR=0.301,95%CI:0.171-0.532,P<0.001), alpha fetoprotein (HR=1.226,95%CI:1.157-1.776,P=0.032) and tumor size (HR=1.008,95%CI:1.001-1.016,P=0.02) were important prognostic factors for overall survival. The area under curve value of 3-year survival prediction model was 0.749(95%CI: 0.712-0.782), and that of 5-year survival prediction model was 0.755(95%CI: 0.724-0.793), with good calibration. Conclusions: Preoperative anti hepatitis B virus(HBV) therapy can significantly improve the prognosis of patients with hepatocellular carcinoma complicated with microvascular tumor thrombus, we develope the prediction models of 3-year and 5-year survival rate that can improve the reference for clinical work and benefit patients.

Pseudoginsenoside-F11 ameliorates thromboembolic stroke injury in rats by reducing thromboinflammation

Pseudoginsenoside-F11 (PF11), an ocotillol-type ginsenoside, has been reported to exert neuroprotective effects on ischemic stroke induced by permanent and transient middle cerebral artery occlusion in experimental animals. The aim of the present study was to investigate the effect of PF11 on thromboembolic stroke in rats and its possible mechanisms on thromboinflammation. PF11 (4, 12, 36 mg/kg) was injected intravenously (i.v.) once a day for 3 consecutive days to male Wistar rats followed by embolic middle cerebral artery occlusion (eMCAO). The results showed that PF11 significantly reduced the cerebral infarction volume, brain edema and neurological deficits induced by eMCAO. Meanwhile, the thromboinflammation in the ischemic hemisphere was observed at 24 h after eMCAO, as indicated by the increased number of microvascular thrombus and inflammatory response. Moreover, eMCAO resulted in the up-regulation of platelet glycoprotein Ibα (GPIbα) and VI (GPVI), as well as the activation of contact-kinin pathway. Notably, PF11 significantly reversed all these changes. Furthermore, PF11 prevented the eMCAO-induced loss of tight junction proteins and up-regulation of matrix metalloproteinase-9 (MMP-9), thus leading to the alleviation of blood-brain barrier (BBB) damage. In conclusion, the present study revealed that thromboinflammation was induced in the ischemic hemisphere of rats after eMCAO and PF11 exerted marked protective effects against thromboembolic stroke by attenuating thromboinflammation and preventing BBB damage. This research further identifies the potential therapeutic role of PF11 for ischemic stroke.

Preliminary results of the phase II ALTER-H004: Anlotinib combined with TACE as adjuvant therapy in hepatocellular carcinoma patients at high risk of post surgery recurrence.

e16125 Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with high incidence and mortality worldwide. Presumably, adjuvant therapy is an efficient treatment for reducing recurrence in patients (pts) with hepatectomy, especially in those with high recurrence factors. Transarterial chemoembolization (TACE) can block the blood supply of the tumor, besides, high concentration of chemotherapeutic drugs can be accumulated within the tumor. It is recommended in several guidelines prophylactic TACE for pts with high recurrence risk factors after hepatectomy, which mainly include grade 1-2 microvascular invasion (M1-2) and portal vein tumor thrombus resection. Moreover, angiogenic inhibitors based therapy has constituted the crucial treatment strategy in HCC. As a novel multitarget tyrosine kinase inhibitor, anlotinib was demonstrated to be an effective first and second-line monotherapy for pts with advanced or recurrent HCC in China. The aim of this phase II trial was to evaluate the efficacy and safety of anlotinib as maintenance adjuvant treatment following inductional TACE in pts with HCC. Methods: A total of 48 histologically confirmed HCC pts who undertook hepatectomy within 1-2 months will be enrolled. The recruited pts who did not recieve any previous tumor-related treatment must have any of the following high risk factors: ≥5cm and &lt;10cm of tumor diameter, tumor number ≥3, tumor microvascular invasion M1 or M2, portal vein tumor thrombus resection (Cheng’s classification Ⅰ/Ⅱ). Enrolled pts were received conventional TACE treatment with pirarubicin or epirubicin and platinum within 1-2 months after hepatectomy. On the 4th day after TACE treatment, oral anlotinib (12mg, qd, 2 weeks on 1 week off) was given until disease recurrence or unacceptable toxicity. The primary endpoint was disease free survival (DFS). Secondary endpoints included 1-year DFS rate, time to recurrence and safety. Results: By the cutoff date of January 26, 2021, 10 pts were enrolled and received at least once tumor assessment. According to RECIST version 1.1, 9 of them did not progress and 1 relapsed, in whom the DFS was 2.4 months. Most of treatment-related adverse events (TRAEs) were rash (20.0% Grade≤2), pain (20.0% Grade=1) and hypertension (10.0% Grade=1). Only one patient had grade 3 TRAE which was leukocytopenia (10.0%). No more grade 3 or above TRAEs occurred. Conclusions: The current results indicated that anlotinib combined with TACE as adjuvant therapy in HCC pts at high recurrence risk exhibited preliminary and implicational anti-tumor efficacy and manageable toxicity. The conclusion should be validated in more pts consecutively. Clinical trial information: NCT04213118.

Edoxaban, a direct oral factor Xa inhibitor, ameliorates coagulation, microvascular thrombus formation, and acute liver injury in a lipopolysaccharide-induced coagulopathy model in rats

Infection increases the risk of thrombosis through the activation of inflammation and coagulation. Edoxaban, a direct oral factor Xa inhibitor, is used for the prevention and treatment of thrombotic diseases. The aim of this study was to determine the effects of edoxaban on microvascular thrombus formation in a rat model of lipopolysaccharide (LPS)-induced coagulopathy. Rats were intravenously injected with 7.5 mg/kg of LPS (Escherichia coli 055:B5). Immediately after LPS injection, the rats were treated with subcutaneous injection of edoxaban. At 2 and 6 h after the injection of LPS, biomarkers of coagulation and organ damages and inflammatory cytokines were measured. Microvascular thrombus formation in organs was evaluated using 125I-fibrinogen (human) or by the pathological analysis. Mortality was examined 24 h after LPS injection. After the injection of LPS, D-dimer and thrombin-antithrombin complex increased and platelet numbers decreased, indicating the activation of coagulation. Microvascular thrombi were found in the liver. Markers of liver injury (aspartate aminotransferase and alanine aminotransferase) also increased. Treatment with edoxaban attenuated the changes in the coagulation markers and microvascular thrombus formation in the liver. Edoxaban suppressed the increase in the liver injury markers and reduced the mortality. Edoxaban did not affect the levels of inflammatory cytokines. In conclusions, edoxaban significantly inhibited the activation of coagulation, the formation of microvascular thrombus in the liver and the liver damage, and reduced mortality in rats injected with LPS. These results suggest that the FXa inhibition by edoxaban might be a beneficial therapy for the management of infection-associated thrombosis.

A multicenter retrospective study on clinical value of lymph node dissection in the radical resection of intrahepatic cholangiocarcinoma

Objective To investigate the clinical value of lymph node dissection (LND) in the radical resection of intrahepatic cholangiocarcinoma (ICC). Methods The propensity score matching and retrospective cohort study was conducted. The clinicopathological data of 448 patients with ICC who were admitted to 12 medical centers from December 2011 to December 2017 were collected, including 279 in the Eastern Hepatobiliary Surgery Hospital of Navy Medical University, 32 in the Mengchao Hepatobiliary Hospital of Fujian Medical University, 21 in the First Hospital Affiliated to Army Medical University, 20 in the Cancer Hospital Chinese Academy of Medical Science and Peking Union Medical College, 19 in the West China Hospital of Sichuan University, 18 in the Second Hospital Affiliated to Zhejiang University School of Medicine, 18 in the Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, 16 in the Beijing Friendship Hospital Affiliated to Capital Medical University, 10 in the Xuanwu Hospital Affiliated to Capital Medical University, 7 in the Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, 5 in the Beijing Tiantan Hospital Affiliated to Capital Medical University, and 3 in the Affiliated Hospital of North Sichuan Medical College. There were 281 males and 167 females, aged from 22 to 80 years, with a median age of 57 years. Of the 448 patients, 143 with routinely intraoperative LND were divided into LND group and 305 without routinely intraoperative LND were divided into control group, respectively. Observation indicators: (1) the propensity score matching conditions and comparison of general data between the two groups after matching; (2) intraoperative and postoperative situations; (3) follow-up; (4) survival analysis. Patients were followed up by outpatient examination, telephone interview and email to detect survival of patients and tumor recurrence up to October 31, 2018 or death. Follow-up was conducted once every 3 months within postoperative 1-2 years, once every 6 months within postoperative 2-5 years, and once a year after 5 years. The propensity score matching was realized using the nearest neighbor method with 1∶1 ratio. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M (range), and comparison between groups was analyzed using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Kaplan-Meier method was used to calculate survival rates and draw survival curve, and Log-rank test was used to perform survival analysis. Univariate analysis and multivaraiate analysis were conducted using the Log-rank test and COX regression model, respectively. Results (1) The propensity score matching conditions and comparison of general data between the two groups after matching: 286 of 448 patients had successful matching, including 143 in each group. The number of males and females, cases with hepatitis, cases with grade A and B of Child-Pugh classification, cases with distance from margin to tumor 0.05). (2) Intraoperative and postoperative situations: the operation time, volume of intraoperative blood loss, cases with intraoperative blood transfusion, cases with postoperative complications, and duration of postoperative hospital stay were 265 minutes (range, 160-371 minutes), 300 mL (range, 200-500 mL), 37, 46, 12 days (range, 9-17 days) for the LND group, and 59 minutes (range, 46-250 minutes), 200 mL (range, 100-400 mL), 24, 25, 9 days (range, 7-11 days) for the control group, respectively. There was no significant difference in the volume of intraoperative blood loss or cases with intraoperative blood transfusion between the two groups (Z=1.700, χ2=3.520, P>0.05). There were significant differences in the operation time, cases with postoperative complications, and duration of postoperative hospital stay (Z=6.520, χ2=8.260, Z=4.270, P 0.05). (4) Survival analysis: results of univariate analysis showed that distance from margin to tumor, tumor diameter, the number of tumors, microvascular tumor thrombus, and lymph node metastasis by pathological examination were related factors for prognosis of patients undergoing radical resection of ICC (χ2=10.662, 9.477, 16.944, 6.520, 11.633, P 5 cm, multiple tumors, microvascular tumor thrombus, positive lymph node metastasis by pathological examination were independent risk factors for prognosis of patients undergoing radical resection of ICC (hazard ratio=0.600, 1.571, 1.601, 1.750, 1.723, 95% confidence interval: 0.430-0.837, 1.106-2.232, 1.115-2.299, 1.083-2.829, 1.207-2.460, P<0.05). Conclusion Lymph node metastasis is an independent risk factor affecting the prognosis of ICC patients, and it is necessary to perform LND in radical resection for patients with ICC and lymph node metastasis. Key words: Bile duct neoplasms; Intrahepatic cholangiocarcinoma; Radical resection; Lymph node dissection; Prognosis; Multicenter; Retrospective

High expression of Anxa2 and Stat3 promote progression of hepatocellular carcinoma and predict poor prognosis

AimTo elucidate whether the interaction between Anxa2 and Stat3 could promote the progression of hepatocellular carcinoma (HCC) and that high co-expression of Anxa2 and Stat3 could predict poor prognosis in HCC patients. MethodsWe investigated Anxa2 and Stat3 expression using Western blot analysis in 4 HCC and adjacent nontumor tissues and using immunohistochemistry in 100 patients’ paraffin sections. Then we assessed the expression of Stat3, Anxa2 and co-expression of Stat3 and Anxa2 with relevant clinical pathological parameters and their prognostic value in HCC patients. The recurrence and overall survival rates were estimated using the Kaplan-Meier method and compared with the log-rank test. The prognostic analysis was carried out with univariate and multivariate Cox regressions models. ResultsThe incidence of high Stat3 expression in HCC tissues (35%) was significantly higher than that in non-HCC tissues (8%) (P < 0.001). The same result was observed in Anxa2 (P < 0.001). Also, the overexpression of Stat3 or Anxa2 showed a significant relationship with the recurrence of the 100 HCC patients (P = 0.012; P = 0.003). Additionally, tumor size >3 cm in diameter, multiple tumor number, and the presence of microvascular tumor thrombus were also significantly associated with recurrence in 100 patients. Then, all enrolled patients were divided into four groups according to IHC score of Stat3 and Anxa2, and the results indicated a significant difference in recurrence time between the subgroups (P < 0.001). What’s more, co-highexpression of Stat3 and Anxa2 was related to the presence of microvascular tumor thrombus (P = 0.003) and poor tumor differentiation (P < 0.001), but not relevant with other clinical features (All P > 0.05). ConclusionThe expression of Stat3, Anxa2, or co-high-expression of the two proteins was associated with HCC recurrence and survival.