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Three cases of neutralization of factor Xa inhibitors with andexanet alfa under rotational thromboelastography monitoring. Acute Med Surg 2024; 11:e954. [PMID: 38655507 PMCID: PMC11036128 DOI: 10.1002/ams2.954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/28/2024] [Accepted: 04/07/2024] [Indexed: 04/26/2024] Open
Abstract
Background Factor Xa inhibitors are direct oral anticoagulants that are extremely useful in clinical applications, safe, and do not require dose adjustment. It is desirable to be able to monitor their effects in the event of hemorrhagic complications requiring neutralization. However, it is difficult to monitor their activity and neutralization using conventional coagulation tests. Case Presentation We report three patients taking factor Xa inhibitors who underwent rotational thromboelastography (ROTEM) monitoring before and after neutralization with andexanet alfa. All three patients had hemorrhagic complications that required neutralization of their factor Xa inhibitors using andexanet alfa. One ROTEM parameter, the EXTEM clotting time (EXTEM-CT), was immediately shortened after andexanet alfa bolus administration, without subsequent extension of the EXTEM-CT assessed 4 h after the bolus dose. Conclusion ROTEM parameters, particularly EXTEM-CT, might be useful for monitoring neutralization of factor Xa inhibitors.
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Preliminary evaluation of reference intervals for a point-of-care viscoelastic coagulation monitor (VCM Vet) in healthy adult horses. J Vet Emerg Crit Care (San Antonio) 2023; 33:540-548. [PMID: 37561043 DOI: 10.1111/vec.13317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 06/01/2022] [Accepted: 06/09/2022] [Indexed: 08/11/2023]
Abstract
OBJECTIVE To evaluate a point-of-care viscoelastic coagulation monitor (VCM Vet) for use in horses by assessing variability between devices and establish reference intervals (RIs) for healthy adult horses. DESIGN Prospective observational study. SETTING Two university teaching hospitals. ANIMALS Healthy adult horses (n = 68). INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Blood collected by direct jugular venipuncture was applied directly from the syringe into 2 VCM Vet cassettes to establish coefficients of variation (CVs) and RIs for reported parameters of clotting time (CT), clot formation time (CFT), alpha angle, amplitude at 10 and 20 minutes, maximum clot firmness, and lysis index at 30 and 45 minutes. CVs for each parameter were within clinical tolerance. There was a significant difference in CT between institutions (P < 0.001). Differences in CV were found between institutions for CT (P = 0.003) and CFT (P = 0.01). Healthy horse RIs were calculated for the overall data set and each individual institution. Calculated RIs were as follows: CT, 255.6-1233.9 seconds; CFT, 89.4-581 seconds; alpha angle, 11.4-53.6°; maximum clot firmness, 18-37.7; lysis index at 30 minutes, 97.3%-102.1%; lysis index at 45 minutes, 80.8%-103.3%; amplitude at 10 minutes, 8.7-28.3; and amplitude at 20 minutes, 17.4-35.7. CONCLUSIONS VCM Vet is a repeatable and practical option for rapid point-of-care assessment of hemostasis in horses but has a wide RI and is susceptible to variability. Establishment of institution-specific RIs is recommended.
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N-acetylcysteine Amide AD4/NACA and Thioredoxin Mimetic Peptides Inhibit Platelet Aggregation and Protect against Oxidative Stress. Antioxidants (Basel) 2023; 12:1395. [PMID: 37507934 PMCID: PMC10376080 DOI: 10.3390/antiox12071395] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 06/28/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
In the present study, we tested the effect of small-molecular-weight redox molecules on collagen-induced platelet aggregation. We used N-acetylcysteine amide (AD4/NACA), the amide form of N-acetylcysteine (NAC), a thiol antioxidant with improved lipophilicity and bioavailability compared to NAC, and the thioredoxin-mimetic (TXM) peptides, TXM-CB3, TXM-CB13, and TXM-CB30. All compounds significantly inhibited platelet aggregation induced by collagen, with TXM-peptides and AD4 being more effective than NAC. The levels of TxB2 and 12-HETE, the main metabolites derived from the cyclooxygenase and lipoxygenase pathways following platelet activation, were significantly reduced in the presence of AD4, TXM peptides, or NAC, when tested at the highest concentration (0.6 mM). The effects of AD4, TXM-peptides, and NAC were also tested on the clotting time (CT) of whole blood. TXM-CB3 and TXM-CB30 showed the greatest increase in CT. Furthermore, two representative compounds, TXM-CB3 and NAC, showed an increase in the anti-oxidant free sulfhydryl groups of plasma detected via Ellman's method, suggesting a contribution of plasma factors to the antiaggregating effects. Our results suggest that these small-molecular-weight redox peptides might become useful for the prevention and/or treatment of oxidative stress conditions associated with platelet activation.
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Experimental design, formulation, and in-vivo evaluation of novel anticoagulant Rivaroxaban loaded cubosomes in rats model. J Liposome Res 2022:1-8. [PMID: 36440581 DOI: 10.1080/08982104.2022.2153137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aim of this study was to develop novel cubosomes as an oral delivery system to improve the permeation and anti-clotting activity of Rivaroxaban (RX). The experimental design (23 full factorial design) was employed to study individual and combined impacts of the assigned formulation variables. The variables RX amount (X1), Poloxamer (PX): GMO (GMO) ratio (X2) and PX/GMO: water ratio (X3) were taken as independent factors, and their effect was examined on entrapment efficiency (Y1), particle size (Y2), and zeta potential. (Y3). The cubosomal vesicle RX-C 3 composed of RX (20 mg), PX: GMO (1:0.5 % w/w), and PX/GMO: water (1:5% w/w) is the optimised formula achieving the required prerequisites. RX-C 3 had shown a vesicle size of 91.2 ± 1.3 nm, entrapment efficiency of 96.27 ± 0.12 %, and zeta potential of -24.1 ± 0.2 mV. The in-vivo studies showed revealed good inhibition of blood clotting, where RX-C 3 significantly increased clotting time by 35% and prothrombin time by 29% compared to Rivarospire®. In conclusion, the present study suggested that oral cubosomes formulations provide prolonged delivery of Rivaroxaban.
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Storage of packed red blood cells impairs an inherent coagulation property of erythrocytes. Front Physiol 2022; 13:1021553. [PMID: 36505041 PMCID: PMC9732456 DOI: 10.3389/fphys.2022.1021553] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/08/2022] [Indexed: 11/26/2022] Open
Abstract
Storage of packed red blood cells is associated with changes in erythrocytes that over time increasingly impair cellular function and potentially contribute to adverse effects associated with blood transfusion. Exposure of phosphatidylserine at the outer membrane leaflet of erythrocytes and shedding of microvesicles (MVs) during packed red blood cell storage are alterations assumed to increase the risk of prothrombotic events in recipients. Here, we used rotational thromboelastometry to study the coagulation process in blood samples with erythrocytes from stored PRBCs reconstituted with freshly prepared platelet-rich plasma. We explored the influence of following effects on the coagulation process: 1) PRBC storage duration, 2) differences between erythrocytes from stored PRBCs compared to freshly drawn erythrocytes, and 3) the contribution of added MVs. Interestingly, despite of a higher fraction of PS-positive cells, erythrocytes from PRBCs stored for 6 weeks revealed longer clotting times than samples with erythrocytes stored for 2 or 4 weeks. Further, clotting times and clot formation times were considerably increased in samples reconstituted with erythrocytes from stored PRBCs as compared to fresh erythrocytes. Moreover, MVs added to reconstituted samples elicited only comparably small and ambiguous effects on coagulation. Thus, this study provides no evidence for an amplified clotting process from prolonged storage of PRBCs but on the contrary implicates a loss of function, which may be of clinical significance in massive transfusion. Our observations add to the increasing body of evidence viewing erythrocytes as active players in the clotting process.
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Silk Fibroin Based Formulations as Potential Hemostatic Agents. ACS Biomater Sci Eng 2022; 8:2654-2663. [PMID: 35616246 DOI: 10.1021/acsbiomaterials.2c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Effective hemorrhage control is indispensable for life-threatening emergencies in defense fields and civilian trauma. During major injuries, hemostatic agents are applied externally to mimic and accelerate the natural hemostasis process. Commercially available topical hemostatic agents are associated with several limitations, e.g., burning sensation, necrosis, futile in severe injuries, and high costs of the products. In the present study, we developed silk fibroin fiber-based formulations and evaluated their use as a cost-effective potential hemostatic agent with shortened clotting time. Silk fiber-based powder was produced following the alkaline hydrolysis process, wherein Bombyx mori silk fibroin fibers were treated with sodium hydroxide (NaOH) solution that randomly chopped the silk microfibers. Physicochemical reaction parameters, e.g., reaction temperature, molarity of NaOH solution, and incubation time, were optimized to achieve the maximum yield of microfibers. The surface properties of alkaline hydrolyzed silk microfibers (AHSMf) were analyzed by field emission scanning electron microscopy and energy dispersive X-ray studies. The water uptake capacity of AHSMf and the change in pH and temperature (∼30 °C) during blood clotting were analyzed. Further, the hemostatic potential of AHSMf was evaluated by an in vitro whole blood clotting assay using both goat and human blood. The in vitro studies demonstrated a reduced blood clotting time (CT = 20-30 s), prothrombin time (PT = ∼27%), and activated partial thromboplastin time (APTT = ∼14%) in the presence of AHSMf when compared to silk hydrogel powder (devoid of NaOH). Thus, the developed AHSMf could be a promising material to serve as a potential hemostatic agent.
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Rennet-Induced Casein Micelle Aggregation Models: A Review. Foods 2022; 11:foods11091243. [PMID: 35563966 PMCID: PMC9101341 DOI: 10.3390/foods11091243] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/07/2022] [Accepted: 04/12/2022] [Indexed: 01/27/2023] Open
Abstract
Two phases are generally recognized in the enzymatic coagulation of milk: hydrolysis and aggregation, although nowadays more and more researchers consider the non-enzymatic phase to actually be a stage of gel formation made up of two sub-stages: micellar aggregation and hardening of the three-dimensional network of para-κ-casein. To evaluate this controversy, the main descriptive models have been reviewed. Most of them can only model micellar aggregation, without modeling the hardening stage. Some are not generalizable enough. However, more recent models have been proposed, applicable to a wide range of conditions, which could differentiate both substages. Manufacturing quality enzymatic cheeses in a cost-effective and consistent manner requires effective control of coagulation, which implies studying the non-enzymatic sub-stages of coagulation separately, as numerous studies require specific measurement methods for each of them. Some authors have recently reviewed the micellar aggregation models, but without differentiating it from hardening. Therefore, a review of the proposed models is necessary, as coagulation cannot be controlled without knowing its mechanisms and the stages that constitute it.
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Tranexamic acid-loaded hemostatic nanoclay microsphere frameworks. J Biomed Mater Res B Appl Biomater 2022; 110:422-430. [PMID: 34288380 PMCID: PMC8678343 DOI: 10.1002/jbm.b.34918] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/30/2021] [Accepted: 07/08/2021] [Indexed: 02/03/2023]
Abstract
Fast acting topical hemostatic agents play a key role in hemorrhage control. Retarding fibrinolysis is also critical in improving coagulation, thereby expanding chances of survival. The purpose of the present work was to investigate the physical properties, loading capacity and hemostatic efficacy of newly developed nanoclay microsphere frameworks (NMFs) loaded with tranexamic acid (TA), as antifibrinolytic agent. Nanoclay compositions were prepared with increasing levels of TA. Results showed that TA was successfully incorporated into the nanoclay structure and released when solvated with ethanol. Both doped and undoped NMFs significantly decreased activated partial thromboplastin time and increased clot stiffness, which was attributed to significantly thinner fibrin fibers and a denser clot structure.
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Molecular mapping of platelet hyperreactivity in diabetes: the stress proteins complex HSPA8/Hsp90/CSK2α and platelet aggregation in diabetic and normal platelets. Transl Res 2021; 235:1-14. [PMID: 33887528 DOI: 10.1016/j.trsl.2021.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 11/15/2022]
Abstract
The molecular understanding of the pathophysiological changes elicited by diabetes in platelets may help in further elucidating the involvement of this pseudo-cell in the increased risk of developing cardiovascular disease and thrombosis in diabetic subjects. We aimed to investigate the differential characteristics of platelets from diabetic patients and nondiabetic controls to unveil the molecular mechanisms behind the increased platelet reactivity in diabetes. We compared platelets from diabetic and control subjects by 2 dimensional-electrophoresis followed by mass spectrometry. Changes in selected differential proteins were validated by immunoprecipitation assays and western blot. Platelet aggregation was measured by light transmittance aggregometry induced by collagen and ADP, and dynamic coagulation analysis of whole blood was measured by thromboelastometry. We observed significant differences in proteins related to platelet aggregation, cell migration, and cell homeostasis. Subjects with diabetes showed higher platelet aggregation and thrombogenicity and higher contents of the stress-related protein complex HSPA8/Hsp90/CSK2α than nondiabetic subjects. Changes in the chaperones HSPA8 and Hsp90, and in CSK2α protein contents correlated with changes in platelet aggregation and blood coagulation activity. In conclusion, the complex HSPA8/Hsp90/CSK2α is involved in diabetes-related platelet hyperreactivity. The role of the HSPA8/Hsp90/CSK2α complex may become a molecular target for the development of future preventive and therapeutic strategies for platelet dysfunction associated with diabetes and its complications.
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Analysis of the effect of varying protamine-to-heparin ratio on coagulation in vitro. Br J Anaesth 2021; 127:e128-e130. [PMID: 34334192 DOI: 10.1016/j.bja.2021.06.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/15/2021] [Accepted: 06/20/2021] [Indexed: 10/20/2022] Open
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New Insights into the Biological Activity of Lichens: Bioavailable Secondary Metabolites of Umbilicaria decussata as Potential Anticoagulants. Chem Biodivers 2021; 18:e2100080. [PMID: 33773025 DOI: 10.1002/cbdv.202100080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 03/26/2021] [Indexed: 11/09/2022]
Abstract
This study reports the in vitro anticoagulation activity of acetonic extract (AE) of 42 lichen species and the identification of potential bioavailable anticoagulant compounds from Umbilicaria decussata as a competent anticoagulant lichen species. Lichens' AEs were evaluated for their anticoagulant activity by monitoring activated partial thromboplastin time (APTT) and prothrombin time (PT) assays. A strong, positive correlation was observed between total phenolics concentration (TPC) of species and blood coagulation parameters. U. decussata was the only species with the longest clotting time in both APTT and PT assays. The research was moved forward by performing in vivo assays using rats. The results corroborated the dose-dependent impact of U. decussata's AE on rats' clotting time. Major secondary metabolites of U. decussata and their plasma-related bioavailability were also investigated using LC-ESI-MS/MS. Atranol, orsellinic acid, D-mannitol, lecanoric acid, and evernic acid were detected as possible bioavailable anticoagulants of U. decussata. Our findings suggest that U. decussata might be a potential anticoagulant lichen species that can be used for the prevention or treatment of coagulation-related issues such as cardiovascular diseases (CVDs).
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Sodium Selenite Improves The Therapeutic Effect Of BMSCs Via Promoting The Proliferation And Differentiation, Thereby Promoting The Hematopoietic Factors. Onco Targets Ther 2020; 12:9685-9696. [PMID: 32009801 PMCID: PMC6859959 DOI: 10.2147/ott.s209937] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 09/17/2019] [Indexed: 12/11/2022] Open
Abstract
Purpose Sodium selenite (Na2SeO3) has been known to restore the antioxidant capacity of bone marrow mesenchymal stem cells (BMSCs), reduce the production of reactive oxygen species (ROS) in the cells, and promote cell proliferation and inhibit cell apoptosis. However, it is still not clear whether selenium can mediate the differentiation and inhibit the induced hemagglutination of BMSCs. In this study, we attempted to explore the effect of Na2SeO3 on these aspects of BMSCs. Methods We evaluated the fate of the MSCs isolated from the bone marrow of mice by studying their differentiation and proliferation after treatment with Na2SeO3. We also simultaneously evaluated the coagulation reaction induced by Na2SeO3-treated BMSCs in vitro. Results While the mice-derived BMSCs expressed CD44, CD73, CD90, and CD105, they did not express CD45. The morphology of the derived cells was homogeneously elongated. These results showed that the isolated cells are indeed BMSCs. We found that 0.1 μM and 1 μM of Na2SeO3 promoted the proliferation and apoptosis of BMSCs, respectively. This showed that Na2SeO3 can be toxic and exert certain side effects on the BMSCs. The results of the osteogenic and adipogenic assay showed that 0.1 μM Na2SeO3 could significantly promote the osteogenic and adipogenic differentiation of BMSCs by upregulating the lipid factors (LPL and PPRAG) and osteogenic factors, RUNX2, COL1, and BGP, in a concentration-dependent manner. Coagulation experiments in animals (mice and rats) revealed that Na2SeO3 can reduce the coagulation time of BMSCs in a concentration-dependent manner, which is related to the high expression of hematopoietic factors (SDF-1α, GM-CSF, IL-7, IL-8, IL-11, and SCF). Conclusion Na2SeO3 promotes the proliferation and differentiation as well as reduces the coagulation time of BMSCs, and this effect might enhance the therapeutic effect of BMSCs.
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In vitro anticoagulant effect of Crassocephalum crepidioides leaf methanol extract and fractions on human blood. J Exp Pharmacol 2019; 11:99-107. [PMID: 31564995 PMCID: PMC6732563 DOI: 10.2147/jep.s218261] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 07/30/2019] [Indexed: 01/11/2023] Open
Abstract
Background Blood coagulation is a rapid and efficient process that produces clot formation which requires regulation. A derangement of blood coagulation is a feature of many disease conditions. This study investigated the in vitro effects of Crassocephalum crepidioides Benth S. Moore leaf methanol (crude) extract and its partitioned solvent fractions on blood coagulation of Healthy human volunteers. Methods The secondary metabolites from dried and ground C. crepidioides leaves were extracted with 70% methanol, and the concentrated crude extract was subsequently subjected to solvent partitioning with Hexane, Ethyl acetate, and Butanol. Varying concentrations (5–20 mg/mL) of the extract and fractions were tested in vitro on blood coagulation profile; clotting time (CT), prothrombin time (PT), and activated partial thromboplastin time (aPTT) of apparently healthy human volunteers, while phytochemical characterization of the Hexane fraction was done by gas chromatography-mass spectrometry (GC-MS). Results C. crepidioides leaf methanol extract and fractions significantly (P<0.05) prolonged the clotting time, prothrombin and activated partial thromboplastin times in the blood obtained from the volunteers. The highest prolongation effect was recorded with the Hexane fraction at concentration of 10mg/mL. GC-MS analysis of the Hexane fraction indicated the presence of phytochemicals such as unsaturated fatty acids and esters, phenolic compounds, flavonoids, and coumarin-related compounds known to exhibit antiaggregant, antiplatelet and antimicrobial activities. Conclusion These results showed that C. crepidioides possesses bioactive components with anticoagulant properties which may be exploited in the treatment of blood coagulation disorders.
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Effects of unidirectional flow shear stresses on the formation, fractal microstructure and rigidity of incipient whole blood clots and fibrin gels. Clin Hemorheol Microcirc 2016; 60:451-64. [PMID: 25624413 PMCID: PMC4923731 DOI: 10.3233/ch-151924] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Incipient clot formation in whole blood and fibrin gels was studied by the rheometric techniques of controlled stress parallel superposition (CSPS) and small amplitude oscillatory shear (SAOS). The effects of unidirectional shear stress on incipient clot microstructure, formation kinetics and elasticity are reported in terms of the fractal dimension (df) of the fibrin network, the gel network formation time (TGP) and the shear elastic modulus, respectively. The results of this first haemorheological application of CSPS reveal the marked sensitivity of incipient clot microstructure to physiologically relevant levels of shear stress, these being an order of magnitude lower than have previously been studied by SAOS. CSPS tests revealed that exposure of forming clots to increasing levels of shear stress produces a corresponding elevation in df, consistent with the formation of tighter, more compact clot microstructures under unidirectional flow. A corresponding increase in shear elasticity was recorded. The scaling relationship established between shear elasticity and df for fibrin clots and whole blood confirms the fibrin network as the dominant microstructural component of the incipient clot in terms of its response to imposed stress. Supplementary studies of fibrin clot formation by rheometry and microscopy revealed the substantial additional network mass required to increase df and provide evidence to support the hypothesis that microstructural changes in blood clotted under unidirectional shear may be attributed to flow enhanced thrombin generation and activation. CSPS also identified a threshold value of unidirectional shear stress above which no incipient clot formation could be detected. CSPS was shown to be a valuable haemorheological tool for the study of the effects of physiological and pathological levels of shear on clot properties.
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Anticoagulant effect and safety assessment of an aqueous extract of Pseudocedrela kotschyi (Schweinf.) harms and Adenia cissampeloides (Planch. Ex Hook.) harms. JOURNAL OF COMPLEMENTARY MEDICINE RESEARCH 2016; 5:153-61. [PMID: 27104036 PMCID: PMC4835990 DOI: 10.5455/jice.20160324054355] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/09/2016] [Indexed: 11/03/2022]
Abstract
BACKGROUND Currently available therapeutic options for thromboembolic disorders are often very expensive and are associated with unfavorable side effects. AIM To establish the anticoagulant effect and safety profile of an extract made from of the root bark of Pseudocedrela kotschyi (Schweinf.) Harms and the aerial part of Adenia cissampeloides (Planch. ex Hook.) Harms (PAE). MATERIALS AND METHODS PAE (0.5-2.0 g/L) effect on prothrombin time (PT) and activated partial thromboplastin time (aPTT) were evaluated on whole blood drawn from the marginal ear vein of New Zealand White rabbits. Effect of PAE (250-2000 mg/kg) on bleeding time (BT) and clotting time (CT) in Sprague-Dawley rats were also assessed. Histopathological, hematological, and liver function studies were also carried out to assess the safety for use of PAE (250-2000 mg/kg). RESULTS PAE had no significant effect (P > 0.05) on PT, but resulted in a significant increase (P ≤ 0.05-0.0001) in aPTT. The PAE treatment resulted in a significant increase (P ≤ 0.05-0.0001) in BT and CT in vivo compared with control. Safety studies indicated no deaths with PAE treatment with hematological and liver function tests being normal. Histological studies revealed pathological changes in the liver at a PAE treatment dose of 2000 mg/kg but all doses had no detrimental effect on kidney and stomach tissue. The no-observed-adverse-effect-level was <2000 mg/kg when given orally. CONCLUSION PAE has anticoagulant effect in vitro and is safe to use at oral doses <2000 mg/kg.
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Abstract
AIM To review hemophilia A with emphasis on its oral manifestations, investigations, and dental management. MATERIALS AND METHODS Search was conducted using internet-based search engines, scholarly bibliographic databases, PubMed, and Medline with key words such as "Hemophilia A," "factor VIII," "bleeding and clotting disorders," and "dental management." RESULTS Hemophilia comprises a group of hereditary disorders caused due to the deficiency of one or more clotting factors leading to prolonged clotting time and excessive bleeding tendencies. It is broadly divided into hemophilia A, B, and C, which occur due to deficiency of factor VIII, IX, and XI, respectively. Hemophilia A is an X-linked recessive hereditary disorder and is the most common of the three, accounting for 80-85% of the cases. CONCLUSION Understanding this complex entity is very important for a dentist to provide appropriate dental treatment and avoid undesirable consequences.
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Postexposure aerosolized heparin reduces lung injury in chlorine-exposed mice. Am J Physiol Lung Cell Mol Physiol 2014; 307:L347-54. [PMID: 25038191 DOI: 10.1152/ajplung.00152.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Chlorine (Cl2) is a highly reactive oxidant gas that, when inhaled, may cause acute lung injury culminating in death from respiratory failure. In this study, we tested the hypothesis that exposure of mice to Cl2 causes intra-alveolar and systemic activation of the coagulation cascade that plays an important role in development of lung injury. C57Bl/6 mice were exposed to Cl2 (400 for 30 min or 600 ppm for 45 min) in environmental chambers and then returned to room air for 1 or 6 h. Native coagulation (NATEM) parameters such as blood clotting time and clot formation time were measured in whole blood by the viscoelastic technique. D-dimers and thrombin-anti-thrombin complexes were measured in both plasma and bronchoalveolar lavage fluid (BALF) by ELISA. Our results indicate that mice exposed to Cl2 gas had significantly increased clotting time, clot formation time, and D-dimers compared with controls. The thrombin-anti-thrombin complexes were also increased in the BALF of Cl2 exposed animals. To test whether increased coagulation contributed to the development of acute lung injury, mice exposed to Cl2 and returned to room air were treated with aerosolized heparin or vehicle for 20 min. Aerosolized heparin significantly reduced protein levels and the number of inflammatory cells in the BALF at 6 h postexposure. These findings highlight the importance of coagulation abnormities in the development of Cl2-induced lung injury.
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Preclinical efficacy and safety of rVIII-SingleChain (CSL627), a novel recombinant single-chain factor VIII. Thromb Res 2013; 132:280-7. [PMID: 23830969 DOI: 10.1016/j.thromres.2013.06.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 06/13/2013] [Accepted: 06/16/2013] [Indexed: 10/26/2022]
Abstract
INTRODUCTION The preclinical efficacy and safety of rVIII-SingleChain (CSL627), a novel recombinant single-chain factor VIII, was assessed in a series of animal studies. MATERIALS AND METHODS In the tail-clip bleeding model, hemophilia A mice were injected with escalating doses (1-150 IU/kg) of rVIII-SingleChain, B-domain deleted (BDD) rFVIII (ReFacto AF(®)), or full-length rFVIII products (Advate(®), Helixate(®)). Total blood loss and the percentage of animals in which hemostasis occurred were assessed in this observer-blinded, randomized study. In a second non-randomized study in hemophilia A mice, thromboelastographic analysis, thrombin generation, and activated partial thromboplastin time assays were performed. General safety and toxicity were assessed in three animal species, including determination of the prothrombotic potential of rVIII-SingleChain in a rabbit venous thrombosis model. RESULTS Under acute bleeding conditions, the effect of rVIII-SingleChain on total blood loss and hemostasis was indistinguishable from BDD and full-length rFVIII. rVIII-SingleChain and full-length rFVIII (both 20 IU/kg) corrected thromboelastographic parameters, activated partial thromboplastin time, and thrombin generation to a similar degree in hemophilia A mice. In a thrombosis model, the effect of rVIII-SingleChain on thrombus incidence was non-significant and comparable to BDD rFVIII at doses up to 500 IU/kg. Treatment with rVIII-SingleChain did not cause anaphylactic reaction or local intolerance in safety and toxicity studies, and demonstrated an excellent overall safety profile. CONCLUSIONS rVIII-SingleChain showed convincing hemostatic efficacy and excellent tolerability in animal studies, warranting continued investigation in human Phase I/III trials (AFFINITY).
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