The impact of small movements with dual lumen cannulae during venovenous extracorporeal membrane oxygenation: A computational fluid dynamics analysis.

BACKGROUND AND OBJECTIVES: Venovenous Extracorporeal Membrane Oxygenation (VV ECMO) provides respiratory support to patients with severe lung disease failing conventional medical therapy. An essential component of the ECMO circuit are the cannulas, which drain and return blood into the body. Despite being anchored to the patient to prevent accidental removal, minor cannula movements are common during ECMO. The clinical and haemodynamic consequences of these small movements are currently unclear. This study investigated the risk of thrombosis and recirculation caused by small movements of a dual lumen cannula (DLC) in an adult using computational fluid dynamics. METHODS: The 3D model of an AVALON Elite DLC (27 Fr) and a patient-specific vena cava and right atrium were generated for an adult patient on ECMO. The baseline cannula position was generated where the return jet enters the tricuspid valve. Alternative cannula positions were obtained by shifting the cannula 5 and 15 mm towards inferior (IVC) and superior (SVC) vena cava, respectively. ECMO settings of 4 L/min blood flow and pulsatile flow at SVC and IVC were applied. Recirculation was defined as a scalar value indicating the infused oxygenated blood inside the drainage lumen, while thrombosis risk was evaluated by shear stress, stagnation volume, washout, and turbulent kinetic energy. RESULTS: Recirculation for all models was less than 3.1 %. DLC movements between -5 to 15 mm increased shear stress and turbulence kinetic energy up to 24.7 % and 11.8 %, respectively, compared to the baseline cannula position leading to a higher predicted thrombosis risk. All models obtained a complete washout after nine seconds except for when the cannula migrated 15 mm into the SVC, indicating persisting stasis and circulating zones. CONCLUSION: In conclusion, small DLC movements were not associated with an increased risk of recirculation. However, they may increase the risk of thrombosis due to increased shear rate, turbulence, and slower washout of blood. Developing effective cannula securement devices may reduce this risk.

A Nonbactericidal Anionic Antimicrobial Peptide Provides Prophylactic and Therapeutic Efficacies against Bacterial Infections in Mice by Immunomodulatory-Antithrombotic Duality.

Although bactericidal cationic antimicrobial peptides (AMPs) have been well characterized, less information is available about the antibacterial properties and mechanisms of action of nonbactericidal AMPs, especially nonbactericidal anionic AMPs. Herein, a novel anionic antimicrobial peptide (Gy-CATH) with a net charge of -4 was identified from the skin of the frog Glyphoglossus yunnanensis. Gy-CATH lacks direct antibacterial effects but exhibits significantly preventive and therapeutic capacities in mice that are infected with Staphylococcus aureus, Enterobacteriaceae coli, methicillin-resistant Staphylococcus aureus (MRSA), or carbapenem-resistant E. coli (CREC). In vitro and in vivo investigations proved the regulation of Gy-CATH on neutrophils and macrophages involved in the host immune defense against infection. Moreover, Gy-CATH significantly reduced the extent of pulmonary fibrin deposition and prevented thrombosis in mice, which was attributed to the regulatory role of Gy-CATH in physiological anticoagulants and platelet aggregation. These findings show that Gy-CATH is a potential candidate for the treatment of bacterial infection.

A real-world study of different doses of rivaroxaban in patients with nonvalvular atrial fibrillation.

To explore the anticoagulant effect and safety of utilizing different doses of rivaroxaban for the treatment of patients with atrial fibrillation (AF) in the real world. A retrospective case-control analysis was performed by applying the hospital database, and 3595 patients with non-valvular atrial fibrillation (NVAF) who were hospitalized and taking rivaroxaban at Wuhan Asia Heart Hospital and Wuhan Asia General Hospital from March 2018 to December 2021 were included in the study, and were divided into the rivaroxaban 10 mg and 15 mg groups according to the daily prescribed dose, of which 443 cases were in the 10 mg group and 3152 cases were in the 15 mg group. The patients were followed up regularly, and the incidence of thrombotic events, bleeding events and all-cause deaths were recorded and compared between the 2 groups, and logistic regression was applied to analyze the influencing factors for the occurrence of adverse events. Comparison of the incidence of thrombosis, bleeding and all-cause death between the 2 groups of patients showed that the 10 mg group was higher than the 15 mg group, but the difference was not statistically significant (χ2 = 0.36, 3.26, 1.99, all P > .05); the incidence of total adverse events between the 2 groups of patients was higher in the 10 mg group than in the 15 mg group, with a statistically significant difference (χ2 = 4.53, P = .033); multifactorial logistic regression results showed that age [OR (95% CI) = 1.02 (1.00-1.04)], diabetes mellitus [OR (95% CI) = 1.69 (1.09-2.62)], D-dimer level [OR (95% CI) = 1.06 (1.00-1.11)] and persistent AF [OR (95% CI) = 1.54 (1.03-2.31)] were risk factors for adverse events (P < .05). In the real world, Asian clinicians recommend rivaroxaban 10 mg once daily for NVAF patients for a variety of reasons; however, this dose is not superior or even inferior to the 15 mg group in terms of effectiveness and safety. Advanced age, elevated D-dimer levels, history of diabetes mellitus, and persistent AF are risk factors for adverse events, and the optimal dosage of rivaroxaban or optimal anticoagulation strategy for Asian patients with nonvalvular AF requires further study.

Effectiveness and safety of rivaroxaban for anticoagulation therapy in COVID-19: A meta-analysis of randomized controlled trials.

OBJECTIVES: To evaluate the effectiveness and safety of rivaroxaban anticoagulation in COVID-19 patients. METHODS: PubMed, Embase, Cochrane Library electronic databases, and ClinicalTrials.gov were searched to identify all relevant randomized controlled trial studies from December 2019 to July 2023. RESULTS: A total of 6 randomized controlled trials, which included a total of 3323 patients, were considered for evaluation. Overall, short-term all-cause mortality and hospitalization rates were not significantly different between the rivaroxaban and control groups. Thrombotic events were significantly reduced in the rivaroxaban prophylaxis group compared to the placebo control group. However, the reduction in thrombotic events was not significantly different between rivaroxaban therapy and heparin or low-molecular-weight heparin (LMWH). Rivaroxaban prophylaxis and the therapeutic dose may be associated with a higher rate of overall bleeding rate, but major bleeding rates did not differ substantially. CONCLUSION: Rivaroxaban may reduce thrombotic events in COVID-19 patients, but it does not appear to have an advantage over heparin or LMWH, and it may increase the risk of bleeding.INPLASY Reg. No.: INPLASY 202370097.

[New anticoagulants in 2024: Development of factor XI and XIa inhibitors]. / Les nouveaux anticoagulants en 2024 : développement des inhibiteurs du facteur XI et du XIa.

Thrombosis remains one of the leading causes of death in the world. The history of anticoagulation has evolved considerably from non-specific drugs (i.e., heparins and vitamin K antagonists, VKA) to agents that directly target specific coagulation factors (i.e., argatroban, fondaparinux and direct oral anticoagulants, DOAC). Since the last decade, DOAC are widely used in clinical practice because of their ease to use, their favorable pharmacological profile and the fact that they do not require monitoring. However, despite having a better safety profile than vitamin K antagonist, their bleeding risk is not negligible. New anticoagulants targeting the contact phase of coagulation are currently being developed and could make it possible to prevent the risk of thrombosis without impairing hemostasis. Epidemiological and preclinical data on FXI deficiency make FXI a promising therapeutic target. The aim of this review is to summarize the results of the various clinical trials available that focus on FXI/FXIa inhibition, and to highlight the challenges that this new therapeutic class of anticoagulants will face.

Protein adsorption on blood-contacting surfaces: A thermodynamic perspective to guide the design of antithrombogenic polymer coatings.

Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. Thrombosis is fundamentally initiated by the nonspecific adsorption of proteins to the material surface, which is strongly governed by thermodynamic factors established by the nature of the interaction between the material surface, surrounding water molecules, and the protein itself. Along these lines, different surface materials (such as polymeric, metallic, ceramic, or composite) induce different entropic and enthalpic changes at the surface-protein interface, with material wettability significantly impacting this behavior. Consequently, protein adsorption on medical devices can be modulated by altering their wettability and surface energy. A plethora of polymeric coating modifications have been utilized for this purpose; hydrophobic modifications may promote or inhibit protein adsorption determined by van der Waals forces, while hydrophilic materials achieve this by mainly relying on hydrogen bonding, or unbalanced/balanced electrostatic interactions. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications. STATEMENT OF SIGNIFICANCE: Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. A plethora of polymeric coating modifications have been utilized for addressing this issue. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications.

Clinical guidelines for prevention and treatment of CAT in Japan and other countries.

Cancer-associated thrombosis (CAT) is an important prognostic factor for an increasing number of cancer patients. Understanding of CAT among cancer care providers has grown in recent years, and guidelines for the prevention and treatment of CAT have been published in Japan and around the world. In this article, we introduce these major guidelines and discuss differences we identified between the Japanese guidelines and those of other countries, with a focus on problems and issues. Insurance coverage of low-molecular-weight heparin and indications for primary prevention with direct oral anticoagulants in particular require urgent consideration.

Efficacy and safety of antiplatelet therapy in COVID-19: Insights from a meta-analysis of randomized controlled trials.

BACKGROUND: COVID-19 induces a pro-coagulant state with thrombotic events. This meta-analysis explores the efficacy and safety of antiplatelet-based therapy in COVID-19 patients through randomized controlled trials (RCTs). MATERIALS AND METHODS: A systematic literature search until March 10, 2023, identified 7 RCTs involving 23,415 inpatients. Of these, 11,891 received antiplatelet-based treatment, and 11,524 received placebo/other drugs. Statistical analysis was performed using Review Manager 5.4. RESULTS: The included trials involved patients with a mean age ranging from 54.3 to 62.0 years and a prevalence of hypertension ranging from 10.9 to 65.0% and coronary artery disease ranging from 3.2 to 32.7%. The pooled analysis showed no significant difference in overall mortality between groups (RR 1.0, 95% CI 0.99 - 1.01, p = 0.76). However, antiplatelet therapy significantly reduced major thrombotic events (RR 0.86, 95% CI 0.75 - 0.99, p = 0.04). Conversely, it increased major bleeding risks (RR 1.62, 95% CI 1.24 - 2.12, p = 0.0005). There was no significant difference in the incidence of invasive mechanical ventilation and respiratory death. CONCLUSION: Antiplatelet therapy does not confer mortality benefit in COVID-19 patients but lowers major thrombotic events while increasing major bleeding risks. Ongoing large RCTs will provide more information on the therapeutic value of this therapy.

Bioinspired superhydrophobic surfaces with silver and nitric oxide-releasing capabilities to prevent device-associated infections and thrombosis.

Bacteria-associated infections and thrombus formation are the two major complications plaguing the application of blood-contacting medical devices. Therefore, functionalized surfaces and drug delivery for passive and active antifouling strategies have been employed. Herein, we report the novel integration of bio-inspired superhydrophobicity with nitric oxide release to obtain a functional polymeric material with anti-thrombogenic and antimicrobial characteristics. The nitric oxide release acts as an antimicrobial agent and platelet inhibitor, while the superhydrophobic components prevent non-specific biofouling. Widely used medical-grade silicone rubber (SR) substrates that are known to be susceptible to biofilm and thrombus formation were dip-coated with fluorinated silicon dioxide (SiO2) and silver (Ag) nanoparticles (NPs) using an adhesive polymer as a binder. Thereafter, the resulting superhydrophobic (SH) SR substrates were impregnated with S-nitroso-N-acetylpenicillamine (SNAP, an NO donor) to obtain a superhydrophobic, Ag-bound, NO-releasing (SH-SiAgNO) surface. The SH-SiAgNO surfaces had the lowest amount of viable adhered E. coli (> 99.9 % reduction), S. aureus (> 99.8 % reduction), and platelets (> 96.1 % reduction) as compared to controls while demonstrating no cytotoxic effects on fibroblast cells. Thus, this innovative approach is the first to combine SNAP with an antifouling SH polymer surface that possesses the immense potential to minimize medical device-associated complications without using conventional systemic anticoagulation and antibiotic treatments.

Overcoming barriers for left atrial appendage thrombus: a systematic review of left atrial appendage closure.

BACKGROUND: Approximately 90% of intracardial thrombi originate from the left atrial appendage in non-valvular atrial fibrillation patients. Even with anticoagulant therapy, left atrial appendage thrombus (LAAT) still occurs in 8% of patients. While left atrial appendage closure (LAAC) could be a promising alternative, the current consensus considers LAAT a contraindication to LAAC. However, the feasibility and safety of LAAC in patients with LAAT have yet to be determined. METHODS: This systematic review synthesizes published data to explore the feasibility and safety of LAAC for patients with LAAT. RESULTS: This study included a total of 136 patients with LAATs who underwent successful LAAC. The Amulet Amplatzer device was the most frequently utilized device (48.5%). Among these patients, 77 (56.6%) had absolute contraindications to anticoagulation therapy. Cerebral protection devices were utilized by 47 patients (34.6%). Transesophageal echocardiography (TEE) is the primary imaging technique used during the procedure. Warfarin and novel oral anticoagulants were the main anticoagulant medications used prior to the procedure, while dual antiplatelet therapy was primarily used post-procedure. During a mean follow-up period of 13.2 ± 11.5 months, there was 1 case of fatality, 1 case of stroke, 3 major bleeding events, 3 instances of device-related thrombus, and 8 cases of peri-device leakage. CONCLUSIONS: This review highlights the preliminary effectiveness and safety of the LAAC procedure in patients with persistent LAAT. Future large-scale RCTs with varied LAAT characteristics and LAAC device types are essential for evidence-based decision-making in clinical practice.

The thrombotic risk in Cushing's syndrome-questions, answers, and the algorithm to consider in its assessment: part I-thrombotic risk not related to surgery.

Introduction: Recently, it has been reported that there is a great diversity in strategies used for thromboprophylaxis in patients with Cushing's syndrome (CS). An aim of this review was to discuss these practices in light of the existing data on the thrombotic risk in patients with CS and guidelines for medically ill patients. Methods: The four relevant topics and questions on thrombotic risk in CS were identified. The current guidelines on prevention and diagnosis of venous thromboembolism (VTE) were reviewed for the answers. An algorithm to consider in the assessment of the thrombotic risk in patients with CS was proposed. Results: To address both generic and CS-specific risk factors for VTE, the algorithm includes the stepwise approach consisting of Padua Score, urine free cortisol, and CS-VTE score, with no indication for routine thrombophilia testing in the prediction of an index VTE episode. Having confirmed VTE, selected patients require thrombophilia testing to aid the duration of anticoagulant treatment. The separate part of the algorithm is devoted to patients with ectopic adrenocorticotropic hormone syndrome in whom exclusion of VTE precedes introducing routine thromboprophylaxis to prevent VTE. The cancer-related VTE also prompts thromboprophylaxis, with the possible vessel invasion. The algorithm presents a unifactorial and multifactorial approach to exclude high-bleeding risks and safely introduce thromboprophylaxis with low-molecular-weight heparin. Summary: Our article is the first to present an algorithm to consider in the thrombotic risk assessment among patients with Cushing's syndrome as a starting point for a broader discussion in the environment. A plethora of factors affect the VTE risk in patients with CS, but no studies have conclusively evaluated the best thromboprophylaxis strategy so far. Future studies are needed to set standards of care.

[Mid-term analysis of prospective cohort study of rivaroxaban in preventing CRT in breast cancer].

Objective: To explore the efficacy and safety of Rivaroxaban in preventing catheter related thrombosis (CRT) in patients with breast cancer who are undergoing central venous catheter chemotherapy, and provide basis for making standardized prevention and treatment strategies. Methods: In this research, a prospective cohort study was adopted, and breast cancer patients who received central venous catheter chemotherapy in Sanhuan Cancer Hospital during September 2020 to March 2022 were selected as a treatment group to take the rivaroxaban anticoagulation therapy with 10 mg.po.qd for one month. The control group got no preventive anticoagulation therapy. Vascular ultrasound examination was taken to confirm the occurrence of CRT, and a chi-square test was done for comparison the disparity between the groups. Logistic regression was applied to analyze the univariate and multivariate factors for the formation of CRT. Results: In the research, a total of 235 patients were selected, and there were a total of 19 035 days of catheterization with 81 days of catheterization on average. While in the control group, the incidence of CRT was 28.0% (33/118), the incidence of CRT in the treatment group was 20.5% (24/117), the difference was no significant (P=0.183). Subgroup analysis results showed that the peripherally inserted central catheter (PICC) was performed in 165 cases with the CRT incidence of 18.2% (30/165) and thrombosis was mostly seen around axillary vein, accounting for 63.3%. Subclavian vein catheterization was performed in 63 cases with the CRT incidence of 39.7% (25/63), and thrombosis was mostly seen around subclavian vein, accounting for 88.0% (22/25). Implantable venous access port was implanted in 7 cases around subclavian vein and internal jugular vein with the CRT incidence of 28.6% (2/7). The patients who developed CRT within 30 days after catheterization accounted for 54.4% (31/57), 22.8% (13/57) in a period during 30 days and 60 days) and 22.8% (13/57) in a period during 60 days and 180 days). The diagnosed CRT patients had been treated with rivaroxaban 15 mg.bid.po for 3 months. During the 3 months, 100.0% of the thrombosis waned, 71.9% (41/57) of the thrombosis waned within 30 days, 19.3% (11/57) in a period during 30 and 60days and 8.8% (5/57) in a period during 60 days and 90 days. Univariate and multivariate analysis indicated that the risk of CRT in subclavian vein catheterization was higher than that in PICC, respectively (OR=2.898, 95% CI:1.386-6.056 P=0.005), and the type of catheterization was an independent factor for the formation of thrombosis. Safety analysis result showed that in the prevention of CRT, rivaroxaban treatment did not induce drug-related bleeding, liver function damage, bone marrow suppression or any other side effects. While CRT diagnosed patients were treated with anticoagulation, they kept the central venous catheter, and the infusion was smooth. These patients all finished the anti-tumor treatment as planned, and no abnormalities like new thrombosis or pulmonary embolism were observed. Conclusions: In the mid-term analysis, the proportion of Rivaroxaban in preventing anticoagulant CRT decreases, but it don't reach statistical significance. The sample size should be further increased for observation. Rivaroxaban is proved effective and very safe in the treatment of CRT, and does not affect the concurrent chemotherapy. Medical personnel should carry out the policy of "early prevention, early detection and early treatment" for CRT so as to improve the patients' quality of life.

In situ formed depot of elastin-like polypeptide-hirudin fusion protein for long-acting antithrombotic therapy.

Thrombosis, induced by abnormal coagulation or fibrinolytic systems, is the most common pathology associated with many life-threatening cardio-cerebrovascular diseases. However, first-line anticoagulant drugs suffer from rapid drug elimination and risk of hemorrhagic complications. Here, we developed an in situ formed depot of elastin-like polypeptide (ELP)-hirudin fusion protein with a prodrug-like feature for long-term antithrombotic therapy. Highly secretory expression of the fusion protein was achieved with the assistance of the Ffu312 tag. Integration of hirudin, ELP, and responsive moiety can customize fusion proteins with properties of adjustable in vivo retention and controllable recovery of drug bioactivity. After subcutaneous injection, the fusion protein can form a reservoir through temperature-induced coacervation of ELP and slowly diffuse into the blood circulation. The biological activity of hirudin is shielded due to the N-terminal modification, while the activated key proteases upon thrombus occurrence trigger the cleavage of fusion protein together with the release of hirudin, which has antithrombotic activity to counteract thrombosis. We substantiated that the optimized fusion protein produced long-term antithrombotic effects without the risk of bleeding in multiple animal thrombosis models.

Atrial Thrombosis Prevalence Before Cardioversion or Catheter Ablation of Atrial Fibrillation: An Updated Systematic Review and Meta-Analysis of Direct Oral Anticoagulants Versus Vitamin K Antagonists.

Left atrial or left atrial appendage thrombosis (LAT) is contraindicated for cardiac ablation (CA) or cardioversion (CV) of atrial fibrillation (AF). This study was aimed to compare the frequency of LAT detected by transesophageal echocardiography (TEE) before CA or CV in patients with AF treated with direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs). We searched PubMed, Scopus, Web of Science, and Cochran Library databases from inception through July 13, 2023 to select studies reporting data on LAT identification before CA or CV using TEE in patients with AF treated with DOACs or VKAs. Pooled odds ratios (ORs) with 95% confidence interval were calculated with a random-effects model. Studies retrieved were 50 (38 observational), 29 on CA, 15 on CV, and 6 on both procedures (17,096 patients on DOACs and 13,666 on VKAs). The overall prevalence of LAT was smaller in DOACs than in VKAs, with an OR of 0.66 (0.52 to 0.84), confirmed at sensitivity analysis and in most subgroups. This finding was consistent for the 3 most reported DOACs: the pooled OR for LAT was 0.68 (0.50 to 0.90) in apixaban, 0.67 (0.51 to 0.88) in dabigatran, 0.61 (0.43 to 0.89) in rivaroxaban, and 1.10 (0.74 to 1.64) in edoxaban (not significant). In conclusion, in this large meta-analysis in patients with AF, the prevalence of LAT by TEE evaluation performed before CV or CA appears lower in those treated with DOACs than in those on VKAs. Additional research may help in better understanding differences between these classes of anticoagulant drugs in the setting of protection against AF-related left atrial thrombotic formation.

Nutrition and Cardiovascular Disease: The Potential Role of Marine Bioactive Proteins and Peptides in Thrombosis Prevention.

Thrombus and cardiovascular diseases pose a significant health threat, and dietary interventions have shown promising potential in reducing the incidence of these diseases. Marine bioactive proteins and peptides have been extensively studied for their antithrombotic properties. They can inhibit platelet activation and aggregation by binding to key receptors on the platelet surface. Additionally, they can competitively anchor to critical enzyme sites, leading to the inhibition of coagulation factors. Marine microorganisms also offer alternative sources for the development of novel fibrinolytic proteins, which can help dissolve blood clots. The advancements in technologies, such as targeted hydrolysis, specific purification, and encapsulation, have provided a solid foundation for the industrialization of bioactive peptides. These techniques enable precise control over the production and delivery of bioactive peptides, enhancing their efficacy and safety. However, it is important to note that further research and clinical studies are needed to fully understand the mechanisms of action and therapeutic potential of marine bioactive proteins and peptides in mitigating thrombotic events. The challenges and future application perspectives of these bioactive peptides also need to be explored.

A synergistic strategy based on active hydroxymethyl amine compounds and fucoidan for bioprosthetic heart valves with enhancing anti-coagulation and anti-calcification properties.

With an aging population, the patients with valvular heart disease (VHD) are growing worldwide, and valve replacement is a primary choice for these patients with severe valvular disease. Among them, bioprosthetic heart valves (BHVs), especially BHVs trough transcatheter aortic valve replacement, are widely accepted by patients on account of their good hemodynamics and biocompatibility. Commercial BHVs in clinic are prepared by glutaraldehyde cross-linked pericardial tissue with the risk of calcification and thrombotic complications. In the present study, a strategy combines improved hemocompatibility and anti-calcification properties for BHVs has been developed based on a novel non-glutaraldehyde BHV crosslinker hexakis(hydroxymethyl)melamine (HMM) and the anticoagulant fucoidan. Besides the similar mechanical properties and enhanced component stability compared to glutaraldehyde crosslinked PP (G-PP), the fucoidan modified HMM-crosslinked PPs (HMM-Fu-PPs) also exhibit significantly enhanced anticoagulation performance with a 72 % decrease in thrombus weight compared with G-PP in ex-vivo shunt assay, along with the superior biocompatibility, satisfactory anti-calcification properties confirmed by subcutaneous implantation. Owing to good comprehensive performance of these HMM-Fu-PPs, this simple and feasible strategy may offer a great potential for BHV fabrication in the future, and open a new avenue to explore more N-hydroxymethyl compound based crosslinker with excellent performance in the field of biomaterials.

Berberine promotes the degradation of phenylacetic acid to prevent thrombosis by modulating gut microbiota.

BACKGROUND: Berberine is the main bioactive constituent of Coptis chinensis, a quaternary ammonium alkaloid. While berberine's cardiovascular benefits are well-documented, its impact on thrombosis remains not fully understood. PURPOSE: This study investigates the potential of intestinal microbiota as a novel target for preventing thrombosis, with a focus on berberine, a natural compound known for its effectiveness in managing cardiovascular conditions. METHODS: Intraperitoneal injection of carrageenan induces the secretion of chemical mediators such as histamine and serotonin from mast cells to promote thrombosis. This model can directly and visually observe the progression of thrombosis in a time-dependent manner. Thrombosis was induced by intravenous injection of 1 % carrageenan solution (20 mg/kg) to all mice except the vehicle control group. Quantitative analysis of gut microbiota metabolites through LC/MS. Then, the gut microbiota of mice was analyzed using 16S rRNA sequencing to assess the changes. Finally, the effects of gut microbiota on thrombosis were explored by fecal microbiota transplantation. RESULTS: Our research shows that berberine inhibits thrombosis by altering intestinal microbiota composition and related metabolites. Notably, berberine curtails the biosynthesis of phenylacetylglycine, a thrombosis-promoting coproduct of the host-intestinal microbiota, by promoting phenylacetic acid degradation. This research underscores the significance of phenylacetylglycine as a thrombosis-promoting risk factor, as evidenced by the ability of intraperitoneal phenylacetylglycine injection to reverse berberine's efficacy. Fecal microbiota transplantation experiment confirms the crucial role of intestinal microbiota in thrombus formation. CONCLUSION: Initiating our investigation from the perspective of the gut microbiota, we have, for the first time, unveiled that berberine inhibits thrombus formation by promoting the degradation of phenylacetic acid, consequently suppressing the biosynthesis of PAG. This discovery further substantiates the intricate interplay between the gut microbiota and thrombosis. Our study advances the understanding that intestinal microbiota plays a crucial role in thrombosis development and highlights berberine-mediated intestinal microbiota modulation as a promising therapeutic approach for thrombosis prevention.

Active Dual-Protein Coating Assisted by Stepwise Protein-Protein Interactions Assembly Reduces Thrombosis and Infection.

Universal protein coatings have recently gained wide interest in medical applications due to their biocompatibility and ease of fabrication. However, the challenge persists in protein activity preservation, significantly complicating the functional design of these coatings. Herein, an active dual-protein surface engineering strategy assisted by a facile stepwise protein-protein interactions assembly (SPPIA) method for catheters to reduce clot formation and infection is proposed. This strategy is realized first by the partial oxidation of bovine serum albumin (BSA) and lysozyme (LZM) for creating stable nucleation platforms via hydrophobic interaction, followed by the assembly of nonoxidized BSA (pI, the isoelectric point, ≈4.7) and LZM (pI ≈11) through electrostatic interaction owing to their opposite charge under neutral conditions. The SPPIA method effectively preserves the conformation and functionality of both BSA and LZM, thus endowing the resultant coating with potent antithrombotic and bactericidal properties. Furthermore, the stable nucleation platform ensures the adhesion and durability of the coating, resisting thrombosis and bacterial proliferation even after 15 days of PBS immersion. Overall, the SPPIA approach not only provides a new strategy for the fabrication of active protein coatings but also shows promise for the surface engineering technology of catheters.

Pharmacologic targeting of coagulation factors XII and XI by monoclonal antibodies reduces thrombosis in nitinol stents under flow.

BACKGROUND: Cardiovascular implantable devices, such as vascular stents, are critical for the treatment of cardiovascular diseases. However, their success is dependent on robust and often long-term antithrombotic therapies. Yet, the current standard-of-care therapies often pose significant bleeding risks to patients. Coagulation factor (F)XI and FXII have emerged as potentially safe and efficacious targets to safely reduce pathologic thrombin generation in medical devices. OBJECTIVES: To study the efficacy of monoclonal antibody-targeting FXII and FXI of the contact pathway in preventing vascular device-related thrombosis. METHODS: The effects of inhibition of FXII and FXI using function-blocking monoclonal antibodies were examined in a nonhuman primate model of nitinol stent-related thrombosis under arterial and venous flow conditions. RESULTS: We found that function-blocking antibodies of FXII and FXI reduced markers of stent-induced thrombosis in vitro and ex vivo. However, FXI inhibition resulted in more effective mitigation of thrombosis markers under varied flow conditions. CONCLUSION: This work provides further support for the translation of contact pathway of coagulation inhibitors for their adjunctive clinical use with cardiovascular devices.