New perspectives on the induction and acceleration of immune-associated thrombosis by PF4 and VWF.

Platelet factor 4 (PF4), also known as chemokine (C-X-C motif) ligand 4 (CXCL4), is a specific protein synthesized from platelet α particles. The combination of PF4 and heparin to form antigenic complexes is an important mechanism in the pathogenesis of heparin-induced thrombocytopenia (HIT), but vaccine-induced immune thrombotic thrombocytopenia (VITT) related to the COVID-19 vaccine makes PF4 a research hotspot again. Similar to HIT, vaccines, bacteria, and other non-heparin exposure, PF4 can interact with negatively charged polyanions to form immune complexes and participate in thrombosis. These anions include cell surface mucopolysaccharides, platelet polyphosphates, DNA from endothelial cells, or von Willebrand factor (VWF). Among them, PF4-VWF, as a new immune complex, may induce and promote the formation of immune-associated thrombosis and is expected to become a new target and therapeutic direction. For both HIT and VITT, there is no effective and targeted treatment except discontinuation of suspected drugs. The research and development of targeted drugs based on the mechanism of action have become an unmet clinical need. Here, this study systematically reviewed the characteristics and pathophysiological mechanisms of PF4 and VWF, elaborated the potential mechanism of action of PF4-VWF complex in immune-associated thrombosis, summarized the current status of new drug research and development for PF4 and VWF, and discussed the possibility of this complex as a potential biomarker for early immune-associated thrombosis events. Moreover, the key points of basic research and clinical evaluation are put forward in the study.

Non-vitamin K antagonist oral anticoagulants in venous thromboembolism patients: a meta-analysis of real-world studies.

BACKGROUND: The real-world studies on recurrent venous thromboembolism (VTE) and bleeding events of non-vitamin K antagonist oral anticoagulants (NOACs) in VTE patients have reported conflicting findings. Our study aimed to provide the direct comparison evidence of different NOACs for VTE patients in clinical practice settings. METHODS: Search of the medical literature was conducted using PubMed, Web of Science, EMBASE, Clinical Trials.gov, and the Cochrane Library from inception to March 22, 2021. Among the 19,996 citations retrieved, a total of 63,144 patients from 6 studies were analyzed. Clinical outcomes included recurrent VTE, death, and different bleeding events. RESULTS: Adjusted hazard ratio (HR) analysis suggested that apixaban had significant lower bleeding riskthan rivaroxaban (major, minor and any bleeding: HR = 0.61, 0.56, 0.70; p = 0.008, < 0.0001, 0.006, respectively), but no statistics difference found in recurrent VTE events (HR = 1.02, 95% confidence interval (CI) 0.71-1.47, p = 0.93). There was no significant difference of major bleeding between dabigatran and rivaroxaban (odds ratios (OR) = 0.41, 95% CI 0.09-1.90, p = 0.25), apixaban and dabigatran (OR 0.64, 95% CI 0.15-2.72, p = 0.83). No significant difference was found in the comparison of edoxaban and other NOACs in VTE recurrence, major bleeding and composite outcome. CONCLUSIONS: In the prevention of bleeding events, apixaban was associated with a lower risk than rivaroxaban, but equivalent efficacy for different NOACs in prevention of recurrent VTE. Evidence generated from the meta-analysis based on real-world data can help to guide selection between apixaban and rivaroxaban in routine clinical practice. TRIAL REGISTRATION: This systematic review and meta-analysis were conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis and Meta-analysis of Observational Studies in Epidemiology statements and was registered with PROSPERO (CRD42019140553).

[Evaluation of the Acute Toxicity and Genotoxicity of the Rice Biofortified with ß-Glucan].

OBJECTIVE: To provide a scientific evaluation of the food safety of the rice biofortified with ß-glucan. METHODS: The acute toxicity and genotoxicity of the rice were evaluated by 14-day feeding experiment, Ames experiment, erythrocyte micronucleus test and mouse lymphoma thymidine kinase gene ( TK) mutation assay respectively. RESULTS: In the acute toxicity test, there was no obvious toxicity of rice biofortified with ß-glucan, and no abnormality was found in anatomical observation. The median lethal dose (LD 50) to rats and mice wereall greater than 15 mg/kg, which belonged to the actual non-toxic level. Whether with S 9 activation or not, no genotoxicity was found to the tested strains TA97a, TA98, TA100, TA102 and TA1535. No induction of polychromatic erythrocytes and inhibition of bone marrow were found in erythrocyte micronucleus test. The results of TK gene mutation assay did not show the mutagenicity of ß-glucan bioaugmentation rice. All results of the three genotoxicity tests were negative. CONCLUSION: Under the current experimental conditions, ß-glucan biofortified rice showed no obvious acute toxicity and genotoxicity.

Predicting ischaemic events using platelet reactivity in patients receiving clopidogrel: Indirect meta-comparison among VerifyNow, light transmission aggregometry and thromboelastography.

The present study compared performances of the three major methods used for assessing platelet reactivity (PR)-VerifyNow, light transmission aggregometry (LTA) and thromboelastography (TEG)-to predict ischaemic events in patients receiving clopidogrel. PubMed, EMBASE and the Cochrane Library were searched from their inception to April 2019 for prospective studies that examined PR using VerifyNow, LTA or TEG and the incidence of ischaemic events. The investigated diagnostic indices include sensitivity, specificity, positive (PLR) and negative likelihood ratio (NLR), diagnostic odds ratio and area under the receiver operating characteristic curves (AUC) of VerifyNow, LTA and TEG, respectively. A total of 26 prospective studies involving 22 185 patients were included in the analysis. The pooled AUC was 0.71 (95% CI: 0.67-0.75) for VerifyNow, 0.60 (95% CI: 0.55-0.64) for LTA and 0.81 (95% CI: 0.77-0.84) for TEG. Results of indirect comparisons indicated the AUC of VerifyNow was higher than that of LTA (1.18, 95% CI: 1.08-1.30) and lower than that of TEG (0.88, 95% CI: 0.82-0.94). TEG outperformed the other two methods for assessing PR in all predictive measures, including sensitivity, specificity, PLR and NLR. Despite a lack of studies that directly compared the three methods, our findings suggest that TEG should be recommended.

The Two-Way Switch Role of ACE2 in the Treatment of Novel Coronavirus Pneumonia and Underlying Comorbidities.

December 2019 saw the emergence of the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which has spread across the globe. The high infectivity and ongoing mortality of SARS-CoV-2 emphasize the demand of drug discovery. Angiotensin-converting enzyme II (ACE2) is the functional receptor for SARS-CoV-2 entry into host cells. ACE2 exists as a membrane-bound protein on major viral target pulmonary epithelial cells, and its peptidase domain (PD) interacts SARS-CoV-2 spike protein with higher affinity. Therefore, targeting ACE2 is an important pharmacological intervention for a SARS-CoV-2 infection. In this review, we described the two-way switch role of ACE2 in the treatment of novel coronavirus pneumonia and underlying comorbidities, and discussed the potential effect of the ACE inhibitor and angiotensin receptor blocker on a hypertension patient with the SARS-CoV-2 infection. In addition, we analyzed the S-protein-binding site on ACE2 and suggested that blocking hot spot-31 and hot spot-353 on ACE2 could be a therapeutic strategy for preventing the spread of SARS-CoV-2. Besides, the recombinant ACE2 protein could be another potential treatment option for SARS-CoV-2 induced acute severe lung failure. This review could provide beneficial information for the development of anti-SARS-CoV-2 agents via targeting ACE2 and the clinical usage of renin-angiotensin system (RAS) drugs for novel coronavirus pneumonia treatment.

The predictive value of circulating microRNAs for venous thromboembolism diagnosis: A systematic review and diagnostic meta-analysis.

OBJECTIVE: Venous thromboembolism (VTE) is a common cardiovascular disease, in which pulmonary embolism (PE) is potentially life-threatening. Accurate biological markers for the early diagnosis of VTE are needed. The purpose of this study was to analyze and validate the predictive value of microRNAs for the diagnosis of VTE. METHODS: A comprehensive literature review was conducted using the PubMed, Embase, and Cochrane Library databases and is current through Sep 27, 2018. The diagnostic value of microRNAs for VTE was analyzed by creating a summary receiver operating characteristic curve (SROC) and calculating the area under the curve (AUC). RESULTS: Our analysis included 12 articles assessing a total of 1057 individuals. The most frequently researched microRNA was miR-134, and the pooled results of the predictive ability of this miRNA with 95% confidence intervals (CIs) showed an average sensitivity of 0.82 (0.69-0.91) and an average specificity of 0.83 (0.68-0.92). The average AUC for the SROC curves was 0.89 (0.86-0.92). For other microRNAs, AUC values >0.8 were considered as potential diagnostic indices. These microRNAs included miR-1233, miR-134, miR-145, miR-483-3p, miR-582, miR-532, and miR-195. CONCLUSIONS: MicroRNAs may act as novel diagnostic biomarkers for VTE, and miR-1233, miR-134, miR-145, miR-483-3p, miR-582, miR-532, and miR-195 are prime candidates. Of these, research on miR-134 is the most extensive and reliable.