Science.gov

Sample records for blood coagulation activation

  1. Contact activation of blood-plasma coagulation

    NASA Astrophysics Data System (ADS)

    Golas, Avantika

    Surface engineering of biomaterials with improved hemocompatibility is an imperative, given the widespread global need for cardiovascular devices. Research summarized in this dissertation focuses on contact activation of FXII in buffer and blood plasma frequently referred to as autoactivation. The extant theory of contact activation imparts FXII autoactivation ability to negatively charged, hydrophilic surfaces. According to this theory, contact activation of plasma involves assembly of proteins comprising an "activation complex" on activating surfaces mediated by specific chemical interactions between complex proteins and the surface. This work has made key discoveries that significantly improve our core understanding of contact activation and unravel the existing paradigm of plasma coagulation. It is shown herein that contact activation of blood factor XII (FXII, Hageman factor) in neat-buffer solution exhibits a parabolic profile when scaled as a function of silanized-glass-particle activator surface energy (measured as advancing water adhesion tension t°a=g° Iv costheta in dyne/cm, where g°Iv is water interfacial tension in dyne/cm and theta is the advancing contact angle). Nearly equal activation is observed at the extremes of activator water-wetting properties --36 < t°a < 72 dyne/cm (O° ≤ theta < 120°), falling sharply through a broad minimum within the 20 < t°a < 40 dyne/cm (55° < theta < 75°). Furthermore, contact activation of FXII in buffer solution produces an ensemble of protein fragments exhibiting either procoagulant properties in plasma (proteolysis of blood factor XI or prekallikrein), amidolytic properties (cleavage of s-2302 chromogen), or the ability to suppress autoactivation through currently unknown biochemistry. The relative proportions of these fragments depend on activator surface chemistry/energy. We have also discovered that contact activation is moderated by adsorption of plasma proteins unrelated to coagulation through an

  2. Activation of blood coagulation in autoimmune skin disorders.

    PubMed

    Cugno, Massimo; Tedeschi, Alberto; Crosti, Carlo; Marzano, Angelo V

    2009-09-01

    The immune system and blood coagulation are simultaneously activated in several inflammatory systemic disorders, such as lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Proinflammatory cytokines, such as IL-6 and TNF-alpha, induce the expression of tissue factor, the main initiator of blood coagulation. Activated proteases of coagulation in turn act on protease-activated receptors, inducing the expression of various proinflammatory cytokines. This cross-talk between inflammation and coagulation amplifies and maintains the activation of both systems. This review focuses on three skin disorders: chronic urticaria (CU), which is considered autoimmune in approximately 50% of cases, bullous pemphigoid (BP), which is the prototype of autoimmune blistering disease, and psoriasis, which is an immune-mediated dermatitis. In CU, the activation of coagulation, which is due to the involvement of eosinophils and tissue factor pathways with the generation of thrombin, has local implications by increasing dermal vascular permeability. Preliminary data indicate that anticoagulant treatment with heparin and warfarin may be effective in reducing the symptoms of this disorder. In BP, the activation of coagulation seems to have both local and systemic implications. Locally, eosinophils and thrombin participate in bulla formation and tissue damage; systemically, the activation of coagulation may explain the increased thrombotic risk observed in these patients. In psoriasis, the activation of coagulation seems to be mainly systemic, potentially contributing to the increased cardiovascular risk associated with this disease. PMID:20477646

  3. Activation of blood coagulation in cancer: implications for tumour progression.

    PubMed

    Lima, Luize G; Monteiro, Robson Q

    2013-09-04

    Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies.

  4. Activation of blood coagulation in cancer: implications for tumour progression

    PubMed Central

    Lima, Luize G.; Monteiro, Robson Q.

    2013-01-01

    Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies. PMID:23889169

  5. [Current views of activating and regulatory mechanisms of blood coagulation].

    PubMed

    Osaki, Tsukasa; Ichinose, Akitada

    2014-07-01

    Coagulation factors play essential roles in not only hemostasis but also thrombosis. The coagulation reaction consists of a stepwise sequence of proteolytic reactions of the coagulation factors, and is generally divided into two pathways, a tissue factor(TF)-dependent "extrinsic pathway" and a contact factor-dependent "intrinsic pathway". The extrinsic pathway is responsible for the initiation of the clotting reaction, while the intrinsic pathway most likely amplifies it. Elevated levels of various coagulation factors such as TF, factor VIII and prothrombin have been linked to an increased thrombotic risk. To prevent thrombus formation, endothelial cells express several receptors and activators for anticoagulant factors such as antithrombin, TF-pathway inhibitor, protein C and protein S. Defects in this anticoagulant system also increase the risk of thrombosis.

  6. [Dependence of haemostasis system response from initial blood coagulation activity under total joints replacement].

    PubMed

    Antropova, I P; Iushkov, B G

    2012-03-01

    Effect of the initial state of the plasma hemostasis on the hemocoagulation changes after the total arthroplasty surgery was studied in 100 patients with osteoarthritis. Indicators of coagulation, fibrinolysis, and physiological anticoagulants were determined before and after completion of the surgery, at days 1, 3, 7, and 13-14 postoperatively. Increased coagulation activity befor surgery enhanced blood clotting within three days after the surgery. Enhanced consumption of physiological anticoagulants reduced the ability to recover their level a week after arthroplasty. The raised activity of the fibrinolysis inhibitor retained the effect during three postoperative days. Initial abnormalities in plasma hemostasis enhance blood coagulation dysfunction caused by surgical intervention on the large joints.

  7. Inherited disorders of blood coagulation.

    PubMed

    Lippi, Giuseppe; Franchini, Massimo; Montagnana, Martina; Favaloro, Emmanuel J

    2012-08-01

    Hemostasis is traditionally defined as a physiological response to blood vessel injury and bleeding, which entails a co-ordinated process involving the blood vessel, platelets, and blood clotting proteins (i.e. coagulation factors). Hemostasis can be divided into primary and secondary components. The former rapidly initiates after endothelial damage and is characterized by vascular contraction, platelet adhesion, and formation of a soft aggregate plug. The latter is initiated following the release of tissue factor and involves a complex sequence of events known as the blood coagulation cascade, encompassing serial steps where each coagulation factor activates another in a chain reaction that culminates in the conversion of fibrinogen to fibrin. Patients carrying abnormalities of the coagulation cascade (i.e. deficiencies of coagulation factors) have an increased bleeding tendency, where the clinical severity is mostly dependent upon the type and the plasma level of the factor affected. These disorders also impose a heavy medical and economic burden on individual patients and society in general. The aim of this article is to provide a general overview on the pathophysiology, clinics, diagnostics, and therapy of inherited disorders of coagulation factors.

  8. Polystyrene nanoparticles affecting blood coagulation.

    PubMed

    Oslakovic, Cecilia; Cedervall, Tommy; Linse, Sara; Dahlbäck, Björn

    2012-08-01

    The association of nanoparticles (NPs) with blood coagulation proteins may influence the natural balance between pro- and anticoagulant pathways. We investigated whether polystyrene NPs, when added to human plasma, affected the generation of thrombin in plasma. Amine-modified NPs were found to decrease the thrombin formation due to binding of factors VII and IX to the NPs, which resulted in depletion of the respective protein in solution. In contrast, carboxyl-modified NPs were able to act as a surface for activation of the intrinsic pathway of blood coagulation in plasma. These results highlight the influence of NPs on a biologically important pathway.

  9. [Condition setting for the measurement of blood coagulation factor XIII activity using a fully automated blood coagulation analyzer, COAGTRON-350].

    PubMed

    Kanno, Nobuko; Kaneko, Makoto; Tanabe, Kumiko; Jyona, Masahiro; Yokota, Hiromitsu; Yatomi, Yutaka

    2012-12-01

    The automated laboratory analyzer COAGTRON-350 (Trinity Biotech) is used for routine and specific coagulation testing for the detection of fibrin formation utilizing either mechanical principles (ball method) or photo-optical principles, chromogenic kinetic enzyme analysis, and immune-turbidimetric detection systems in one benchtop unit. In this study, we demonstrated and established a parameter for the measurement of factor XIII (FXIII) activity using Berichrom FXIII reagent and the COAGTRON-350 analyzer. The usual protocol used for this reagent, based on the handling method, was slightly modified for this device. The analysis showed that fundamental study for the measurement of FXIII activity under our condition setting was favorable in terms of reproducibility, linearity, and correlation with another assays. Since FXIII is the key enzyme that plays important roles in hemostasis by stabilizing fibrin formation, the measurement of FXIII is essential for the diagnosis of bleeding disorders. Therefore, FXIII activity assessment as well as a routine coagulation testing can be conducted simultaneously with one instrument, which is useful in coagulopathy assessment.

  10. Lowering blood glucose during hip surgery does not influence coagulation activation

    PubMed Central

    Sechterberger, Marjolein K.; Hermanides, Jeroen; Poolman, Rudolf W.; Kal, Jasper E.; Meijers, Joost C.M.; Hoekstra, Joost B.L.; Hans DeVries, J.

    2015-01-01

    Background Hyperglycaemia during and after hip surgery is associated with coagulation activation and an increased risk of venous thromboembolism. Whether lowering of glucose levels during hip surgery diminishes coagulation activation is unknown. We investigated the efficacy of the human GLP-1 analogue liraglutide to lower glucose during and after hip surgery and studied its influence on coagulation activation. Methods A total of 37 obese subjects who underwent hip surgery were randomized to subcutaneous liraglutide or placebo for 4 consecutive days, starting one day prior to surgery. Glucose levels and coagulation indices at three fixed time-points (pre-operative, 2 h post-operative and 3 days post-operative) were measured. Results Liraglutide reduced glucose at day three post-surgery (median glucose (IQR) liraglutide 5.5 (5.2–5.7) vs. placebo 5.8 (5.5–6.2); difference 0.3 mmol/L, P = 0.04). Changes in 6 out of 8 coagulation indices studied did not differ between the two groups. Only D-dimer levels were significantly lower in the liraglutide group at day three post-surgery and FVIII levels were significantly higher in the liraglutide group 2 h post-surgery. Conclusion Although the human GLP-1 analogue liraglutide moderately reduced post-operative blood glucose levels in non-diabetic and prediabetic obese patients undergoing elective hip surgery, no changes were observed with respect to coagulation activation. PMID:26675337

  11. Moringa oleifera Lam.: Protease activity against blood coagulation cascade

    PubMed Central

    Satish, A; Sairam, Sudha; Ahmed, Faiyaz; Urooj, Asna

    2012-01-01

    Background: The present study evaluated the protease activity of aqueous extracts of Moringa oleifera (Moringaceae) leaf (MOL) and root (MOR). Materials and Methods: Protease activity was assayed using casein, human plasma clot and human fibrinogen as substrates. Results: Caseinolytic activity of MOL was significantly higher (P ≤ 0.05) than that of MOR. Similar observations were found in case of human plasma clot hydrolyzing activity, wherein MOL caused significantly higher (P ≤ 0.05) plasma clot hydrolysis than MOR. Zymographic techniques were used to detect proteolytic enzymes following electrophoretic separation in gels. Further, both the extracts exhibited significant procoagulant activity as reflected by a significant decrease (P ≤ 0.05) in recalcification time, accompanied by fibrinogenolytic and fibrinolytic activities; clotting time was decreased from 180 ± 10 sec to 119 ± 8 sec and 143 ± 10 sec by MOL and MOR, respectively, at a concentration of 2.5 mg/mL. Fibrinogenolytic (human fibrinogen) and fibrinolytic activity (human plasma clot) was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), plate method and colorimetric method. Zymographic profile indicated that both the extracts exerted their procoagulant activity by selectively hydrolyzing Aα and Bβ subunits of fibrinogen to form fibrin clot, thereby exhibiting fibrinogenolytic activity. However, prolonged incubation resulted in degradation of the formed fibrin clot, suggesting fibrinolytic like activity. Conclusions: These findings support the traditional usage of M. oleifera extracts for wound healing. PMID:22224061

  12. [Monitoring of blood coagulation in perioperative care].

    PubMed

    Ishii, Hisanari

    2012-01-01

    Coagulation disorders often occur perioperatively and monitoring of blood coagulation should be fast and adequate to treat these disorders to protect patients from massive bleeding. Control of hemostasis is one of the main issues in major surgeries. Coagulation test results from a central laboratory may delay making such a perioperative decision. Recently, point-of-care monitoring (POCM), which is able to examine coagulation disorder in an operation theater with short waiting time, has become important. Both prothrombin time (PT) and activated clotting time (ACT) are very useful and popular, but also criticized because they can be monitored only until fibrin formation. On the other hand, viscoelastic monitorings of whole blood, are able to estimate fibrin formation, clot fixation, platelet function and fibrinolysis. In this review article, among variable perioperative POCMs of blood coagulation, three thromboelastographic monitorings, such as TEG ROTEM, and Sonoclot as well as PT and ACT, are described along with their utilities and limits to examine perioperative coagulation.

  13. Perioperative pharmacology: blood coagulation modifiers.

    PubMed

    Hicks, Rodney W; Wanzer, Linda J; Goeckner, Bradlee

    2011-06-01

    Blood coagulation is the process that results in the formation of a blood clot to stop bleeding from a damaged blood vessel. Various pharmacologic agents can affect the coagulation process. The American College of Chest Physicians' evidence-based practice guidelines for perioperative management of antithrombotic therapy provide guidance for anticoagulant or antiplatelet therapy and bridge therapy. Perioperative nurses must understand the pharmacologic principles of the most common blood coagulation modifiers related to perioperative use. The perioperative nurse's responsibilities regarding administration of blood coagulation modifiers include reviewing the patient's pertinent laboratory results (eg, prothrombin time, partial thromboplastin time, international normalized ratio), recognizing the underlying conditions that require blood coagulation therapy, and documenting all pertinent information. Perioperative nurses also should participate in development of detailed storage and retrieval policies related to heparin.

  14. Lonomia obliqua caterpillar spicules trigger human blood coagulation via activation of factor X and prothrombin.

    PubMed

    Donato, J L; Moreno, R A; Hyslop, S; Duarte, A; Antunes, E; Le Bonniec, B F; Rendu, F; de Nucci, G

    1998-03-01

    In southern Brazil, envenomation by larvae of the moth Lonomia obliqua (Walker) may result in blood clotting factor depletion, leading to disseminated intravascular coagulation with subsequent haemorrhage and acute renal failure which may prove fatal. We have examined the effect of a crude extract of spicules from these caterpillars on in vitro hemostasis. The extract alone did not aggregate platelets and had no detectable effect on purified fibrinogen, suggesting that extract induces clot formation by triggering activation of the clotting cascade. In agreement with the presence of thrombin-mediated activity, hirudin prevented clot formation. The extract was found to activate both prothrombin and factor X, suggesting that the depletion of blood clotting factors results from the steady activation of factor X and prothrombin. Heating and diisopropylfluorophosphate abolished the procoagulant activity of the extract, indicating that the active component involved is a protein that may belong to the serine protease family of enzymes. The ability of hirudin to inhibit this coagulant activity suggests that this inhibitor could be beneficial in the treatment of patients envenomed by L. obliqua caterpillars. PMID:9531036

  15. Early markers of blood coagulation and fibrinolysis activation in Argentine hemorrhagic fever.

    PubMed

    Heller, M V; Marta, R F; Sturk, A; Maiztegui, J I; Hack, C E; Cate, J W; Molinas, F C

    1995-03-01

    Junin virus, an arenaviridae, is the etiological agent of Argentine hemorrhagic fever. In addition to thrombocytopenia, patients present several alterations in both the blood coagulation and the fibrinolytic system, but diffuse intravascular coagulation could not be demonstrated. To investigate further the activation status of the two systems, levels of thrombin-antithrombin complexes (TAT), prothrombin fragment 1 + 2, protein C, total and free protein S, C4bBP, antithrombin III, t-PA, PAI-1 and D-dimer were measured. Fourteen patients with a confirmed diagnosis of Argentine hemorrhagic fever were included in the study, 2 were severe, 3 moderate and 9 mild clinical cases, but hemorrhages were slight throughout. Blood samples were collected for 6 consecutive days on admission and on remission. At admission TAT and F1 + 2 levels were increased in 13/14 patients, reaching 0.33 nM (0.06-0.87) and 2.16 nM (0.96-6.5), respectively. PC was low in 4 cases, fPS in 6 and tPS in 2, whereas C4bBP and ATIII values were within normal range. t-PA and D-dimer levels were high in 11/14 patients, reaching 20 ng/ml (2.7-106) and 1660 ng/ml (877-3780) respectively, while PAI-1 was considerably increased in the 2 severe cases and normal in the remainder. These results suggest low level though persistent process of blood coagulation and fibrinolysis activation in this viral hemorrhagic disease. We believe these abnormalities may lead to the well described bleeding manifestations in these patients.

  16. Effects of dietary fat quality and quantity on postprandial activation of blood coagulation factor VII.

    PubMed

    Larsen, L F; Bladbjerg, E M; Jespersen, J; Marckmann, P

    1997-11-01

    Acute elevation of the coagulant activity of blood coagulation factor VII (FVIIc) is observed after consumption of high-fat meals. This elevation is caused by an increase in the concentration of activated FVII (FVIIa). In a randomized crossover study, we investigated whether saturated, monounsaturated, or polyunsaturated fats differed regarding postprandial activation of FVII. Eighteen healthy young men participated in the study. On 6 separate days each participant consumed two meals (times, 0 and 1 3/4 hours) enriched with 70 g (15 and 55 g) of either rapeseed oil, olive oil, sunflower oil, palm oil, or butter (42% of energy from fat) or isoenergetic low-fat meals (6% of energy from fat). Fasting and series of nonfasting blood samples (the last at time 8 1/2 hours) were collected. Plasma triglycerides, FVIIc, FVIIa, and free fatty acids were analyzed. There were marked effects of the fat quantity on postprandial responses of plasma triglycerides, FVII, and free fatty acids. The high-fat meals caused, in contrast to the low-fat meals, considerable increases in plasma triglycerides. Plasma levels of FVIIc and FVIIa peaks were 7% and 60% higher after consumption of high-fat meals than after consumption of low-fat meals. The five different fat qualities caused similar postprandial increases in plasma triglycerides, FVIIc, and FVIIa. These findings indicate that high-fat meals may be prothrombotic, irrespective of their fatty acid composition. The postprandial FVII activation was not associated with the plasma triglyceride or free fatty acid responses.

  17. Coagulating activity of the blood, vascular wall, and myocardium under hypodynamia conditions

    NASA Technical Reports Server (NTRS)

    Petrovskiy, B. V. (Editor); Chazov, E. I. (Editor); Andreyev, S. V. (Editor)

    1980-01-01

    In order to study the effects of hypodynamia on the coagulating properties of the blood, vascular wall, and myocardium, chinchilla rabbits were kept for varying periods in special cages which restricted their movements. At the end of the experiment, blood samples were taken and the animals were sacrificed. Preparations were made from the myocardium venae cavae, and layers of the aorta. Two resultant interrelated and mutually conditioned syndromes were discovered: thrombohemorrhagic in the blood and hemorrago-thrombotic in the tissues.

  18. Contact activation of blood coagulation on a defined kaolin/collagen surface in a microfluidic assay.

    PubMed

    Zhu, Shu; Diamond, Scott L

    2014-12-01

    Generation of active Factor XII (FXIIa) triggers blood clotting on artificial surfaces and may also enhance intravascular thrombosis. We developed a patterned kaolin (0 to 0.3 pg/μm(2))/type 1 collagen fibril surface for controlled microfluidic clotting assays. Perfusion of whole blood (treated only with a low level of 4 μg/mL of the XIIa inhibitor, corn trypsin inhibitor) drove platelet deposition followed by fibrin formation. At venous wall shear rate (100 s(-1)), kaolin accelerated onset of fibrin formation by ~100 sec when compared to collagen alone (250 sec vs. 350 sec), with little effect on platelet deposition. Even with kaolin present, arterial wall shear rate (1000 s(-1)) delayed and suppressed fibrin formation compared to venous wall shear rate. A comparison of surfaces for extrinsic activation (tissue factor TF/collagen) versus contact activation (kaolin/collagen) that each generated equal platelet deposition at 100 s(-1) revealed: (1) TF surfaces promoted much faster fibrin onset (at 100 sec) and more endpoint fibrin at 600 sec at either 100 s(-1) or 1000 s(-1), and (2) kaolin and TF surfaces had a similar sensitivity for reduced fibrin deposition at 1000 s(-1) (compared to fibrin formed at 100 s(-1)) despite differing coagulation triggers. Anti-platelet drugs inhibiting P2Y1, P2Y12, cyclooxygenase-1 or activating IP-receptor or guanylate cyclase reduced platelet and fibrin deposition on kaolin/collagen. Since FXIIa or FXIa inhibition may offer safe antithrombotic therapy, especially for biomaterial thrombosis, these defined collagen/kaolin surfaces may prove useful in drug screening tests or in clinical diagnostic assays of blood under flow conditions.

  19. Contact activation of blood coagulation on a defined kaolin/collagen surface in a microfluidic assay

    PubMed Central

    Zhu, Shu; Diamond, Scott L.

    2014-01-01

    Generation of active Factor XII (FXIIa) triggers blood clotting on artificial surfaces and may also enhance intravascular thrombosis. We developed a patterned kaolin (0 to 0.3 pg/μm2)/type 1 collagen fibril surface for controlled microfluidic clotting assays. Perfusion of whole blood (treated only with a low level of 4 μg/mL of the XIIa inhibitor, corn trypsin inhibitor) drove platelet deposition followed by fibrin formation. At venous wall shear rate (100 s−1), kaolin accelerated onset of fibrin formation by ~100 sec when compared to collagen alone (250 sec vs. 350 sec), with little effect on platelet deposition. Even with kaolin present, arterial wall shear rate (1000 s−1) delayed and suppressed fibrin formation compared to venous wall shear rate. A comparison of surfaces for extrinsic activation (tissue factor TF/collagen) versus contact activation (kaolin/collagen) that each generated equal platelet deposition at 100 s−1 revealed: (1) TF surfaces promoted much faster fibrin onset (at 100 sec) and more endpoint fibrin at 600 sec at either 100 s−1 or 1000 s−1, and (2) kaolin and TF surfaces had a similar sensitivity for reduced fibrin deposition at 1000 s−1 (compared to fibrin formed at 100 s−1) despite differing coagulation triggers. Anti-platelet drugs inhibiting P2Y1, P2Y12, cyclooxygenase-1 or activating IP-receptor or guanylate cyclase reduced platelet and fibrin deposition on kaolin/collagen. Since FXIIa or FXIa inhibition may offer safe antithrombotic therapy, especially for biomaterial thrombosis, these defined collagen/kaolin surfaces may prove useful in drug screening tests or in clinical diagnostic assays of blood under flow conditions. PMID:25303860

  20. Contact activation of blood coagulation on a defined kaolin/collagen surface in a microfluidic assay.

    PubMed

    Zhu, Shu; Diamond, Scott L

    2014-12-01

    Generation of active Factor XII (FXIIa) triggers blood clotting on artificial surfaces and may also enhance intravascular thrombosis. We developed a patterned kaolin (0 to 0.3 pg/μm(2))/type 1 collagen fibril surface for controlled microfluidic clotting assays. Perfusion of whole blood (treated only with a low level of 4 μg/mL of the XIIa inhibitor, corn trypsin inhibitor) drove platelet deposition followed by fibrin formation. At venous wall shear rate (100 s(-1)), kaolin accelerated onset of fibrin formation by ~100 sec when compared to collagen alone (250 sec vs. 350 sec), with little effect on platelet deposition. Even with kaolin present, arterial wall shear rate (1000 s(-1)) delayed and suppressed fibrin formation compared to venous wall shear rate. A comparison of surfaces for extrinsic activation (tissue factor TF/collagen) versus contact activation (kaolin/collagen) that each generated equal platelet deposition at 100 s(-1) revealed: (1) TF surfaces promoted much faster fibrin onset (at 100 sec) and more endpoint fibrin at 600 sec at either 100 s(-1) or 1000 s(-1), and (2) kaolin and TF surfaces had a similar sensitivity for reduced fibrin deposition at 1000 s(-1) (compared to fibrin formed at 100 s(-1)) despite differing coagulation triggers. Anti-platelet drugs inhibiting P2Y1, P2Y12, cyclooxygenase-1 or activating IP-receptor or guanylate cyclase reduced platelet and fibrin deposition on kaolin/collagen. Since FXIIa or FXIa inhibition may offer safe antithrombotic therapy, especially for biomaterial thrombosis, these defined collagen/kaolin surfaces may prove useful in drug screening tests or in clinical diagnostic assays of blood under flow conditions. PMID:25303860

  1. In vitro and in vivo evaluation of blood coagulation activation of polyvinyl alcohol hydrogel plus dextran-based vascular grafts.

    PubMed

    Alexandre, Nuno; Costa, Elísio; Coimbra, Susana; Silva, Alice; Lopes, Ascensão; Rodrigues, Miguel; Santos, Marta; Maurício, Ana Colette; Santos, José Domingos; Luís, Ana Lúcia

    2015-04-01

    Polyvinyl alcohol hydrogel (PVA) is a water-soluble synthetic polymer that is commonly used in biomedical applications including vascular grafting. It was argued that the copolymerization of PVA with dextran (Dx) can result in improvement of blood-biomaterial interactions. The focus of this experimental study was to assess that interaction through an in vivo and in vitro evaluation of the coagulation system activation. The thrombogenicity of the copolymer was determined by quantification of platelet adhesion through the lactate dehydrogenase assay, determination of whole blood clotting time, and by quantification of platelet activation by flow cytometry. The thrombin-antithrombin complex blood levels were also determined. The obtained results for the in vitro assays suggested a non-thrombogenic profile for PVA/Dx. Additionally in vivo coagulation and hematological parameters were determined in an animal model after PVA/Dx vascular graft implantation. For coagulation homeostasis assessment, the intrinsic and extrinsic pathway's activation was determined by measuring prothrombin time (PT) and activated partial thromboplastin time (aPTT). Other markers of coagulation and inflammation activation including d-dimers, interleukin-6, and C-reactive protein were also assessed. The PVA/Dx copolymer tended to inhibit platelet adhesion/activation process and the contact activation process for coagulation. These results were also confirmed with the in vivo experiments where the measurements for APTT, interleukin-6, and C-reactive protein parameters were normal considering the species normal range of values. The response to those events is an indicator of the in vitro and in vivo hemocompatibility of PVA/Dx and it allows us to select this biomaterial for further preclinical trials in vascular reconstruction.

  2. Novel aspects of blood coagulation factor XIII. I. Structure, distribution, activation, and function

    SciTech Connect

    Muszbek, L.; Adany, R.; Mikkola, H.

    1996-10-01

    Blood coagulation factor XIII (FXIII) is a protransglutaminase that becomes activated by the concerted action of thrombin and Ca{sup 2+} in the final stage of the clotting cascade. In addition to plasma, FXIII also occurs in platelets, monocytes, and monocyte-derived macrophages. While the plasma factor is a heterotetramer consisting of paired A and B subunits (A{sub 2}B{sub 2}), its cellular counterpart lacks the B subunits and is a homodimer of potentially active A subunits (A{sub 2}). The gene coding for the A and B subunits has been localized to chromosomes 6p24-25 and 1q31-32.1, respectively. The genomic as well as the primary protein structure of both subunits has been established. Plasma FXIII circulates in association with its substrate precursor, fibrinogen. Fibrin(ogen) has an important regulatory role in the activation of plasma FXIII, for instance the proteolytic removal of activation peptide by thrombin, the dissociation of subunits A and B, and the exposure of the originally buried active site on the free A subunits. The end result of this process is the formation of an active transglutaminase, which crosslinks peptide chains through {epsilon}({gamma}-glutamyl)lysyl isopeptide bonds. The protein substrates of activated FXIII include components of the clotting-fibrinolytic system, adhesive and contractile proteins. The main physiological function of plasma FXIII is to cross-link fibrin and protect it from the fibrinolytic enzyme plasmin. The latter effect is achieved mainly by covalently linking {alpha}{sub 2} antiplasmin, the most potent physiological inhibitor of plasmin, to fibrin. Plasma FXIII seems to be involved in wound healing and tissue repair, and it is essential to maintaining pregnancy. Cellular FXIII, if exposed to the surface of the cells, might support or perhaps take over the hemostatic functions of plasma FXIII; however, its intracellular role has remained mostly unexplored. 328 refs., 4 figs.

  3. EPCR-dependent PAR2 activation by the blood coagulation initiation complex regulates LPS-triggered interferon responses in mice.

    PubMed

    Liang, Hai Po H; Kerschen, Edward J; Hernandez, Irene; Basu, Sreemanti; Zogg, Mark; Botros, Fady; Jia, Shuang; Hessner, Martin J; Griffin, John H; Ruf, Wolfram; Weiler, Hartmut

    2015-04-30

    Infection and inflammation are invariably associated with activation of the blood coagulation mechanism, secondary to the inflammation-induced expression of the coagulation initiator tissue factor (TF) on innate immune cells. By investigating the role of cell-surface receptors for coagulation factors in mouse endotoxemia, we found that the protein C receptor (ProcR; EPCR) was required for the normal in vivo and in vitro induction of lipopolysaccharide (LPS)-regulated gene expression. In cultured bone marrow-derived myeloid cells and in monocytic RAW264.7 cells, the LPS-induced expression of functionally active TF, assembly of the ternary TF-VIIa-Xa initiation complex of blood coagulation, and the EPCR-dependent activation of protease-activated receptor 2 (PAR2) by the ternary TF-VIIa-Xa complex were required for the normal LPS induction of messenger RNAs encoding the TLR3/4 signaling adaptor protein Pellino-1 and the transcription factor interferon regulatory factor 8. In response to in vivo challenge with LPS, mice lacking EPCR or PAR2 failed to fully initiate an interferon-regulated gene expression program that included the Irf8 target genes Lif, Iigp1, Gbp2, Gbp3, and Gbp6. The inflammation-induced expression of TF and crosstalk with EPCR, PAR2, and TLR4 therefore appear necessary for the normal evolution of interferon-regulated host responses.

  4. Blood coagulation in falciparum malaria--a review.

    PubMed

    Ghosh, Kanjaksha; Shetty, Shrimati

    2008-03-01

    Falciparum malaria infection influences blood coagulation by various interacting pathobiological mechanisms, the most important being the overwhelming response of the host to sepsis resulting in a cytokine storm. In addition, the parasite infects the red cells leading to changes in the red cell phospholipid composition which supports blood coagulation. Red cells infected with Plasmodium falciparum also adhere to deeper tissue capillary endothelium leading to profound damage to endothelial cells leading to further activation. This results in widespread consumption of platelets and activation of blood coagulation which at times culminates in a clinically and pathologically detectable disseminated intravascular coagulation (DIC). Monocyte-macrophage system also gets activated in this infection compounding the hypercoagulable state. Heavy parasitaemia leading to occlusion of hepatic microcirculation leads to abnormalities in synthesis and secretion of coagulation factors and their inhibitors. Drugs used in the treatment for falciparum malaria can cause thrombocytopaenia, bone marrow suppression and haemolytic anaemia, all of which can interfere indirectly with blood coagulation. Microparticle formation from platelets, red cells and macrophages also causes widespread activation of blood coagulation, and this recently observed mechanism is the focus of intense research in many other inflammatory and neoplastic conditions where there is activation of blood coagulation system. Thus, in severe falciparum malaria, there is activation of blood coagulation system along with thrombocytopaenia, even before widespread DIC and coagulation failure occur.

  5. Erythrocyte-derived microparticles supporting activated protein C-mediated regulation of blood coagulation.

    PubMed

    Koshiar, Ruzica Livaja; Somajo, Sofia; Norström, Eva; Dahlbäck, Björn

    2014-01-01

    Elevated levels of erythrocyte-derived microparticles are present in the circulation in medical conditions affecting the red blood cells. Erythrocyte-derived microparticles expose phosphatidylserine thus providing a suitable surface for procoagulant reactions leading to thrombin formation via the tenase and prothrombinase complexes. Patients with elevated levels of circulating erythrocyte-derived microparticles have increased thrombin generation in vivo. The aim of the present study was to investigate whether erythrocyte-derived microparticles are able to support the anticoagulant reactions of the protein C system. Erythrocyte-derived microparticles were isolated using ultracentrifugation after incubation of freshly prepared erythrocytes with the ionophore A23187 or from outdated erythrocyte concentrates, the different microparticles preparations yielding similar results. According to flow cytometry analysis, the microparticles exposed phoshatidylserine and bound lactadherin, annexin V, and protein S, which is a cofactor to activated protein C. The microparticles were able to assemble the tenase and prothrombinase complexes and to stimulate the formation of thrombin in plasma-based thrombin generation assay both in presence and absence of added tissue factor. The addition of activated protein C in the thrombin generation assay inhibited thrombin generation in a dose-dependent fashion. The anticoagulant effect of activated protein C in the thrombin generation assay was inhibited by a monoclonal antibody that prevents binding of protein S to microparticles and also attenuated by anti-TFPI antibodies. In the presence of erythrocyte-derived microparticles, activated protein C inhibited tenase and prothrombinase by degrading the cofactors FVIIIa and FVa, respectively. Protein S stimulated the Arg306-cleavage in FVa, whereas efficient inhibition of FVIIIa depended on the synergistic cofactor activity of protein S and FV. In summary, the erythrocyte-derived microparticle

  6. The effect of substrate molecular mobility on surface induced immune complement activation and blood plasma coagulation.

    PubMed

    Berglin, Mattias; Andersson, Marcus; Sellborn, Anders; Elwing, Hans

    2004-08-01

    Changing the length of the alkyl ester side chain in poly(alkyl methacrylates) provides a unique opportunity to systematically vary the mobility of the polymer chains, or in other words vary the glass transition temperature (T(g)), without greatly affect the solid surface energy (gamma(s)) of the polymer. A series of poly(alkyl methacrylate) coatings was therefore analysed with regard to the human immune complement (IC) activation and the surface associated blood plasma coagulation cascade (CC) properties. For the IC and CC measurements we used a quartz crystal microbalance (QCM) where we modified the chemistry of the sensor surface by applying 10-30 nm thick poly(alkyl methacrylate) coatings. The surface energy was calculated from water contact angles and small differences between the coatings were observed. The surface chemistry of the coatings, as determined with X-ray photoelectron spectroscopy (XPS), showed no deviation from expected compositions. Tapping mode atomic force microscopy (TM-AFM) measurements revealed that all coatings displayed similar morphology and the roughness was in the range of 0.7-0.9 nm. Increased polymer mobility correlated with a decrease in IC activation, measured as a decreased C3c deposition at the surface. The surface induced CC, measured as fibrin clot formation at the surface, was different between the different coatings but no correlation with molecular mobility was observed. Thus, the molecular mobility of the polymer chains had a major effect on both the IC and the CC and it seems that different aspects of the chemistry of the solid surface regulate activation of the IC and the CC.

  7. Activation of Blood Coagulation in Two Prototypic Autoimmune Skin Diseases: A Possible Link with Thrombotic Risk.

    PubMed

    Cugno, Massimo; Tedeschi, Alberto; Borghi, Alessandro; Bucciarelli, Paolo; Asero, Riccardo; Venegoni, Luigia; Griffini, Samantha; Grovetti, Elena; Berti, Emilio; Marzano, Angelo Valerio

    2015-01-01

    Coagulation activation has been demonstrated in two prototypic autoimmune skin diseases, chronic autoimmune urticaria and bullous pemphigoid, but only the latter is associated with increased thrombotic risk. Two markers of coagulation activation (prothrombin fragment F1+2 and fibrin fragment D-dimer) were measured by immunoenzymatic methods in plasma samples from 30 patients with active chronic autoimmune urticaria, positive for autologous serum skin test, 30 patients with active bullous pemphigoid and 30 healthy subjects. In skin biopsies, tissue factor expression was evaluated by both immunohistochemistry and in situ hybridization. F1+2 and D-dimer levels were higher in active chronic autoimmune urticaria (276.5±89.8 pmol/L and 5.56±4.40 nmol/L, respectively) than in controls (145.2±38.0 pmol/L and 1.06±0.25 nmol/L; P=0.029 and P=0.011) and were much higher in active bullous pemphigoid (691.7±318.7 pmol/L and 15.24±9.09 nmol/L, respectively) (P<0.0001). Tissue factor positivity was evident in skin biopsies of both disorders with higher intensity in bullous pemphigoid. F1+2 and D-dimer, during remission, were markedly reduced in both disorders. These findings support the involvement of coagulation activation in the pathophysiology of both diseases. The strong systemic activation of coagulation in bullous pemphigoid may contribute to increase the thrombotic risk and provides the rationale for clinical trials on anticoagulant treatments in this disease.

  8. The pro-coagulant fibrinogenolytic serine protease isoenzymes purified from Daboia russelii russelii venom coagulate the blood through factor V activation: role of glycosylation on enzymatic activity.

    PubMed

    Mukherjee, Ashis K

    2014-01-01

    Proteases from Russell's viper venom (RVV) induce a variety of toxic effects in victim. Therefore, four new RVV protease isoenzymes of molecular mass 32901.044 Da, 333631.179 Da, 333571.472 Da, and 34594.776 Da, were characterized in this study. The first 10 N-terminal residues of these serine protease isoenzymes showed significant sequence homology with N-terminal sequences of snake venom thrombin-like and factor V-activating serine proteases, which was reconfirmed by peptide mass fingerprinting analysis. These proteases were found to be different from previously reported factor V activators isolated from snake venoms. These proteases showed significantly different fibrinogenolytic, BAEE-esterase and plasma clotting activities but no fibrinolytic, TAME-esterase or amidolytic activity against the chromogenic substrate for trypsin, thrombin, plasmin and factor Xa. Their Km and Vmax values towards fibrinogen were determined in the range of 6.6 to 10.5 µM and 111.0 to 125.5 units/mg protein, respectively. On the basis of fibrinogen degradation pattern, they may be classified as A/B serine proteases isolated from snake venom. These proteases contain ∼ 42% to 44% of N-linked carbohydrates by mass whereas partially deglycosylated enzymes showed significantly less catalytic activity as compared to native enzymes. In vitro these protease isoenzymes induce blood coagulation through factor V activation, whereas in vivo they provoke dose-dependent defibrinogenation and anticoagulant activity in the mouse model. At a dose of 5 mg/kg, none of these protease isoenzymes were found to be lethal in mice or house geckos, suggesting therapeutic application of these anticoagulant peptides for the prevention of thrombosis. PMID:24520323

  9. [Cellular model of blood coagulation process].

    PubMed

    Bijak, Michał; Rzeźnicka, Paulina; Saluk, Joanna; Nowak, Paweł

    2015-07-01

    Blood coagulation is a process which main objective is the prevention of blood loss when the integrity of the blood vessel is damaged. Over the years, have been presented a number of concepts characterizing the mechanism of thrombus formation. Since the 60s of last century was current cascade model of the coagulation wherein forming of the fibrin clot is determined by two pathways called extrinsic and intrinsic pathways. In the nineties of the last century Monroe and Hoffman presented his concept of blood coagulation process which complement the currently valid model of cells participation especially of blood platelets which aim is to provide a negatively charged phospholipid surface and thereby allow the coagulation enzymatic complexes formation. Developed conception they called cellular model of coagulation. The aim of this work was to present in details of this blood coagulation, including descriptions of its various phases.

  10. The activated coagulation time of whole blood as a routine pre-operative sceening test.

    PubMed

    Hattersley, P G

    1971-05-01

    Patients with disorders of hemostasis who undergo surgical procedures are in danger of hemorrhage. While the careful medical history remains the most sensitive test of a bleeding tendency, some such patients can give no suggestive history. In three patients with coagulopathy-one with mild classical hemophilia, one with Christmas disease, and one with warfarin toxicity-the abnormality was missed by routine preoperative history but promptly detected by the routine preoperative use of the activated coagulation time (act). Either this test or the activated partial thromboplastin time should be included in the routine preoperative work-up, along with appropriate additional tests of the hemostatic mechanism.

  11. [Physiology of blood coagulation and fibrinolysis: biochemistry].

    PubMed

    Preissner, K T

    2008-12-01

    The principles of initiator and amplifications reactions of blood coagulation and fibrinolysis will be presented and discussed in relation to various regulatory pathways of haemostasis. In particular, cell surface-dependent activation and inhibition reactions are characteristics of multicomponent enzyme complexes that also allow the endogenous control of the haemostasis system. The understanding of these relationships in complications of haemostasis has lead to different strategies for the therapeutic intervention with pro- and anticoagulant substances. PMID:19132158

  12. Interactions of PLGA nanoparticles with blood components: protein adsorption, coagulation, activation of the complement system and hemolysis studies

    NASA Astrophysics Data System (ADS)

    Fornaguera, Cristina; Calderó, Gabriela; Mitjans, Montserrat; Vinardell, Maria Pilar; Solans, Conxita; Vauthier, Christine

    2015-03-01

    The intravenous administration of poly(lactic-co-glycolic) acid (PLGA) nanoparticles has been widely reported as a promising alternative for delivery of drugs to specific cells. However, studies on their interaction with diverse blood components using different techniques are still lacking. Therefore, in the present work, the interaction of PLGA nanoparticles with blood components was described using different complementary techniques. The influence of different encapsulated compounds/functionalizing agents on these interactions was also reported. It is worth noting that all these techniques can be simply performed, without the need for highly sophisticated apparatus or skills. Moreover, their transference to industries and application of quality control could be easily performed. Serum albumin was adsorbed onto all types of tested nanoparticles. The saturation concentration was dependent on the nanoparticle size. In contrast, fibrinogen aggregation was dependent on nanoparticle surface charge. The complement activation was also influenced by the nanoparticle functionalization; the presence of a functionalizing agent increased complement activation, while the addition of an encapsulated compound only caused a slight increase. None of the nanoparticles influenced the coagulation cascade at low concentrations. However, at high concentrations, cationized nanoparticles did activate the coagulation cascade. Interactions of nanoparticles with erythrocytes did not reveal any hemolysis. Interactions of PLGA nanoparticles with blood proteins depended both on the nanoparticle properties and the protein studied. Independent of their loading/surface functionalization, PLGA nanoparticles did not influence the coagulation cascade and did not induce hemolysis of erythrocytes; they could be defined as safe concerning induction of embolization and cell lysis.The intravenous administration of poly(lactic-co-glycolic) acid (PLGA) nanoparticles has been widely reported as a promising

  13. Activation of blood coagulation and the activity of cancer procoagulant (EC 3.4.22.26) in breast cancer patients.

    PubMed

    Mielicki, W P; Tenderenda, M; Rutkowski, P; Chojnowski, K

    1999-11-01

    The activity of cancer procoagulant (CP), prothrombin time (PT), activated partial thromboplastin time (APTT), the concentration of thrombin-antithrombin complexes (TAT) and the concentration of fibrinogen were analysed in blood of breast cancer patients scheduled for surgery. The serum level of CP activity was dependent on the stage of the disease. The CP activity was increased in 72% of patients with an early stage of cancer and in only 20% of patients with an advanced stage of the disease when compared to the baseline level for non-cancer controls. In all patients PT remained at normal levels (80-120%). There was no significant change in APTT (27-39 s) in early stage cancer patients. Only one patient with advanced cancer had APTT shortened to 23 s. Also one advanced stage patient had significantly elevated level of TAT (14.96 microg/l); in all other patients the concentration of TAT remained at normal levels (1-4.1 microg/l). Forty-four percent of early stage cancer patients and 22% of advanced cancer patients had an elevated level of fibrinogen (Fg) ( > 350 mg%). However, there was no correlation between the level of Fg and the CP activity (P > 0.05). The data suggest that: (1) serum CP activity increases at the early stage of breast cancer and decreases down to the normal level in the advanced stage of the disease; (2) there is no evidence of blood clotting activation in the early stage breast cancer patients; and (3) CP does not facilitate the activation of coagulation in the breast cancer patients or the level of such activation is below the sensitivity of assays used in the experiment.

  14. Whole blood coagulation and platelet activation in the athlete: A comparison of marathon, triathlon and long distance cycling

    PubMed Central

    2010-01-01

    Introduction Serious thrombembolic events occur in otherwise healthy marathon athletes during competition. We tested the hypothesis that during heavy endurance sports coagulation and platelets are activated depending on the type of endurance sport with respect to its running fraction. Materials and Methods 68 healthy athletes participating in marathon (MAR, running 42 km, n = 24), triathlon (TRI, swimming 2.5 km + cycling 90 km + running 21 km, n = 22), and long distance cycling (CYC, 151 km, n = 22) were included in the study. Blood samples were taken before and immediately after completion of competition to perform rotational thrombelastometry. We assessed coagulation time (CT), maximum clot firmness (MCF) after intrinsically activation and fibrin polymerization (FIBTEM). Furthermore, platelet aggregation was tested after activation with ADP and thrombin activating peptide 6 (TRAP) by using multiple platelet function analyzer. Results Complete data sets were obtained in 58 athletes (MAR: n = 20, TRI: n = 19, CYC: n = 19). CT significantly decreased in all groups (MAR -9.9%, TRI -8.3%, CYC -7.4%) without differences between groups. In parallel, MCF (MAR +7.4%, TRI +6.1%, CYC +8.3%) and fibrin polymerization (MAR +14.7%, TRI +6.1%, CYC +8.3%) were significantly increased in all groups. However, platelets were only activated during MAR and TRI as indicated by increased AUC during TRAP-activation (MAR +15.8%) and increased AUC during ADP-activation in MAR (+50.3%) and TRI (+57.5%). Discussion While coagulation is activated during physical activity irrespective of type we observed significant platelet activation only during marathon and to a lesser extent during triathlon. We speculate that prolonged running may increase platelet activity, possibly, due to mechanical alteration. Thus, particularly prolonged running may increase the risk of thrombembolic incidents in running athletes. PMID:20452885

  15. Evaluation of optical coherence tomography for the measurement of the effects of activators and anticoagulants on the blood coagulation in vitro.

    PubMed

    Xu, Xiangqun; Geng, Jinhai; Liu, Gangjun; Chen, Zhongping

    2013-08-01

    Optical properties of human blood during coagulation were studied using optical coherence tomography (OCT) and the parameter of clotting time derived from the 1/e light penetration depth (d(1/e)) versus time was developed in our previous work. In this study, in order to know if a new OCT test can characterize the blood-coagulation process under different treatments in vitro, the effects of two different activators (calcium ions and thrombin) and anticoagulants, i.e., acetylsalicylic acid (ASA, a well-known drug aspirin) and melagatran (a direct thrombin inhibitor), at various concentrations are evaluated. A swept-source OCT system with a 1300 nm center wavelength is used for detecting the blood-coagulation process in vitro under a static condition. A dynamic study of d1/e reveals a typical behavior due to coagulation induced by both calcium ions and thrombin, and the clotting time is concentration-dependent. Dose-dependent ASA and melagatran prolong the clotting times. ASA and melagatran have different effects on blood coagulation. As expected, melagatran is much more effective than ASA in anticoagulation by the OCT measurements. The OCT assay appears to be a simple method for the measurement of blood coagulation to assess the effects of activators and anticoagulants, which can be used for activator and anticoagulant screening.

  16. Influence of red algal sulfated polysaccharides on blood coagulation and platelets activation in vitro.

    PubMed

    Sokolova, Ekaterina V; Byankina, Anna O; Kalitnik, Alexandra A; Kim, Yong H; Bogdanovich, Larisa N; Solov'eva, Tamara F; Yermak, Irina M

    2014-05-01

    The influence of sulfated polysaccharides (λ-, κ-, and κ/β-carrageenan and porphyran) - on platelet activation was studied. Carrageenans were much weaker inhibitors of a coagulation process than heparin, while porphyran had not that effect. Results of the aPTT and PT assays suppose that carrageenans affected mostly intrinsic pathway of coagulation, while their effect on the extrinsic pathway is extremely low (λ and κ/β) or absent (κ, LMW derivative of κ-carrageenan). λ-Carrageenan was the most potent anticoagulant agent in TT, aPTT, PT, and anti-factor Xa activity. This sample was also the strongest inhibitor of collagen-induced platelet aggregation in PRP. Generally, the correlation of anticoagulant and antithrombotic action in PRP is preserved for carrageenans but not for heparin. Carrageenans and porphyran affected platelet adhesion to collagen by influencing glycoprotein VI. Low molecular weight κ-carrageenan had a similar effect on platelet adhesion mediated with both major collagen receptors: integrin α2 β1 and glycoprotein VI as native polysaccharide had. Carrageenans resulted in activation of platelets under platelet adhesion mediated by integrin αIIb β3 with less degree than heparin. The least sulfated κ/β-carrageenan that possessed an inhibiting effect on thrombin- and collagen-induced aggregation of washed platelets and on the PT test but it had no significant effect on TT was the weakest promoter of integrin αIIb β3 mediated platelet activation. In summary, our study showed that the polysaccharide action was complex, since it depended on its molecular mass, sulfation degree, and monosaccharide contents (3,6-anhydrogalactose).

  17. Positive feedback loops for factor V and factor VII activation supply sensitivity to local surface tissue factor density during blood coagulation.

    PubMed

    Balandina, A N; Shibeko, A M; Kireev, D A; Novikova, A A; Shmirev, I I; Panteleev, M A; Ataullakhanov, F I

    2011-10-19

    Blood coagulation is triggered not only by surface tissue factor (TF) density but also by surface TF distribution. We investigated recognition of surface TF distribution patterns during blood coagulation and identified the underlying molecular mechanisms. For these investigations, we employed 1), an in vitro reaction-diffusion experimental model of coagulation; and 2), numerical simulations using a mathematical model of coagulation in a three-dimensional space. When TF was uniformly immobilized over the activating surface, the clotting initiation time in normal plasma increased from 4 min to >120 min, with a decrease in TF density from 100 to 0.7 pmol/m(2). In contrast, surface-immobilized fibroblasts initiated clotting within 3-7 min, independently of fibroblast quantity and despite a change in average surface TF density from 0.5 to 130 pmol/m(2). Experiments using factor V-, VII-, and VIII-deficient plasma and computer simulations demonstrated that different responses to these two TF distributions are caused by two positive feedback loops in the blood coagulation network: activation of the TF-VII complex by factor Xa, and activation of factor V by thrombin. This finding suggests a new role for these reactions: to supply sensitivity to local TF density during blood coagulation.

  18. Systems biology of coagulation initiation: kinetics of thrombin generation in resting and activated human blood.

    PubMed

    Chatterjee, Manash S; Denney, William S; Jing, Huiyan; Diamond, Scott L

    2010-09-30

    Blood function defines bleeding and clotting risks and dictates approaches for clinical intervention. Independent of adding exogenous tissue factor (TF), human blood treated in vitro with corn trypsin inhibitor (CTI, to block Factor XIIa) will generate thrombin after an initiation time (T(i)) of 1 to 2 hours (depending on donor), while activation of platelets with the GPVI-activator convulxin reduces T(i) to ∼20 minutes. Since current kinetic models fail to generate thrombin in the absence of added TF, we implemented a Platelet-Plasma ODE model accounting for: the Hockin-Mann protease reaction network, thrombin-dependent display of platelet phosphatidylserine, VIIa function on activated platelets, XIIa and XIa generation and function, competitive thrombin substrates (fluorogenic detector and fibrinogen), and thrombin consumption during fibrin polymerization. The kinetic model consisting of 76 ordinary differential equations (76 species, 57 reactions, 105 kinetic parameters) predicted the clotting of resting and convulxin-activated human blood as well as predicted T(i) of human blood under 50 different initial conditions that titrated increasing levels of TF, Xa, Va, XIa, IXa, and VIIa. Experiments with combined anti-XI and anti-XII antibodies prevented thrombin production, demonstrating that a leak of XIIa past saturating amounts of CTI (and not "blood-borne TF" alone) was responsible for in vitro initiation without added TF. Clotting was not blocked by antibodies used individually against TF, VII/VIIa, P-selectin, GPIb, protein disulfide isomerase, cathepsin G, nor blocked by the ribosome inhibitor puromycin, the Clk1 kinase inhibitor Tg003, or inhibited VIIa (VIIai). This is the first model to predict the observed behavior of CTI-treated human blood, either resting or stimulated with platelet activators. CTI-treated human blood will clot in vitro due to the combined activity of XIIa and XIa, a process enhanced by platelet activators and which proceeds in the

  19. Prothrombin activation fragment 1 + 2 as a marker of coagulation activation in cord blood collection for banking.

    PubMed

    Juutistenaho, S; Vahtera, E; Aranko, K; Kekomäki, R

    2010-08-01

    There have been efforts to increase the quality of cord blood (CB) collections aimed at banking and transplantation. Yet, the effect of CB collection techniques on haemostatic activation is scarcely studied, despite the unique nature of the neonatal haemostatic system. The aim of this study was to explore coagulation system and platelet (PLT) activation during CB collection at a national CB bank. At three time points over a 9-year period (in 1998, 2000 and 2006), CB collections were assessed to evaluate the collection process during bank setup and changes in procedures. Thrombin generation and PLT activation were assessed with prothrombin activation fragment 1 + 2 (F1 + 2) and PLT factor 4 (PF4), respectively. The median F1 + 2 level was 2.8 nmol L(-1) in 1998 (n = 11), 0.7 nmol L(-1) in 2000 (n = 10) and 0.7 nmol L(-1) in 2006 (n = 6), the decrease being statistically significant (1998 vs 2000, P < 0.001; 1998 vs 2006, P = 0.01). The median PF4 level was 117 IU mL(-1) in 1998 and 104 IU mL(-1) in 2000. PF4 was not measured in 2006. The level of F1 + 2 correlated with that of PF4 (n = 21; Spearman's Rho = 0.59, P = 0.006). Haemostatic activation, assessed as a part of CB bank process control, decreased from the first to the subsequent sample series. F1 + 2 may be a candidate for quality control in CB banking; however, further studies are needed to optimise the analyses and to assess the effect of haemostatic activation on CB quality. PMID:20345383

  20. Blood coagulation disorders in septic patients.

    PubMed

    Knoebl, Paul

    2010-03-01

    Host defense and blood coagulation are tightly connected and interacting systems, necessary for the integrity of an organism. Complex mechanisms regulate the intensity of a host response to invading pathogens or other potentially dangerous situations. Under regular conditions, this response is limited in time and located to the site of injury. Sometimes, however, systemic host response is overwhelming and disproportional and causes damage, not cure. Dependent on the genetical predisposition of the host, its current immunocompetence, or the type of injury, the reaction leads to the clinical picture of the different degrees of sepsis. Septic organ dysfunction is caused by intravascular fibrin deposition as a result of coagulation activation, anticoagulant breakdown, and shut down of fibrinolysis. This article describes the major pathophysiologic reactions in these situations and presents www.SepDIC.eu, an online tool on sepsis and associated coagulopathy.

  1. Relationship between circulating tumor cells, blood coagulation, and urokinase-plasminogen-activator system in early breast cancer patients.

    PubMed

    Mego, Michal; Karaba, Marian; Minarik, Gabriel; Benca, Juraj; Sedlácková, Tatiana; Tothova, Lubomira; Vlkova, Barbora; Cierna, Zuzana; Janega, Pavol; Luha, Jan; Gronesova, Paulina; Pindak, Daniel; Fridrichova, Ivana; Celec, Peter; Reuben, James M; Cristofanilli, Massimo; Mardiak, Jozef

    2015-01-01

    Cancer is a risk factor for venous thromboembolism (VTE) and plasma d-dimer (DD) and tissue factor (TF) are established VTE associated markers. Circulating tumor cells (CTCs) are associated with the risk of VTE in metastatic breast cancer. This study aimed to correlate CTCs, blood coagulation and the urokinase plasminogen activator (uPA) system in primary breast cancer (PBC) patients. This prospective study included 116 PBC patients treated by primary surgery. CTCs were detected by quantitative RT-PCR assay for expression of epithelial (CK19) or epithelial-mesenchymal transition (EMT) genes (TWIST1, SNAIL1, SLUG, ZEB1, FOXC2). Plasma DD, TF, uPA system proteins were detected by enzyme-linked immunosorbent assays, while expressions of uPA system in surgical specimens were evaluated by immunohistochemistry. CTCs were detected in 27.6% patients. Patients with CTCs had a significantly higher mean plasma DD (ng/mL) than those of patients without CTCs (632.4 versus 365.4, p = 0.000004). There was no association between plasma TF and CTCs. Epithelial CTCs exhibit higher expression of uPA system genes compared to EMT_CTCs. Patients with CTCs had higher plasma uPA proteins than those of patients without CTCs; there was no correlation between tissue expression of uPA system, CTCs, DD or TF levels. In multivariate analysis CTCs and patients age were independent factors associated with plasma DD. We found association between plasma DD and CTCs indicating a potential role for activation of the coagulation cascade in the early metastatic process. CTCs could be directly involved in coagulation activation or increased CTCs could be marker of aggressive disease and increased VTE risk.

  2. Colloidal Confinement of Polyphosphate on Gold Nanoparticles Robustly Activates the Contact Pathway of Blood Coagulation.

    PubMed

    Szymusiak, Magdalena; Donovan, Alexander J; Smith, Stephanie A; Ransom, Ross; Shen, Hao; Kalkowski, Joseph; Morrissey, James H; Liu, Ying

    2016-01-20

    Platelet-sized polyphosphate (polyP) was functionalized on the surface of gold nanoparticles (GNPs) via a facile conjugation scheme entailing EDAC (N-(3-(dimethylamino)propyl)-N'-ethylcarbodiimide hydrochloride)-catalyzed phosphoramidation of the terminal phosphate of polyP to cystamine. Subsequent reduction of the disulfide moiety allowed for anchoring to the colloidal surface. The ability of the synthesized polyP-GNPs to initiate the contact pathway of clotting in human pooled normal plasma (PNP) was then assayed by quantifying changes in viscous, mechanical, and optical properties upon coagulation. It is revealed that the polyP-GNPs are markedly superior contact activators compared to molecularly dissolved, platelet-sized polyP (of equivalent polymer chain length). Moreover, the particles' capacity to mobilize Factor XII (FXII) and its coactivating proteins appear to be identical to very-long-chain polyP typically found in bacteria. These data imply that nanolocalization of anionic procoagulants on colloidal surfaces, achieved through covalent anchoring, may yield a robust contact surface with the ability to sufficiently cluster active clotting factors together above their threshold concentrations to cease bleeding. The polyP-GNPs therefore serve as a promising foundation in the development of a nanoparticle hemostat to treat a range of hemorrhagic scenarios. PMID:26624923

  3. Blood Coagulation Induced by Iranian Saw-Scaled Viper (Echis Carinatus) Venom: Identification, Purification and Characterization of a Prothrombin Activator

    PubMed Central

    Babaie, Mahdi; Salmanizadeh, Hossein; Zolfagharian, Hossein

    2013-01-01

    Objective(s): Echis carinatus is one of the venomous snakes in Iran. The venom of Iranian Echis carinatus is a rich source of protein with various factors affecting the plasma protein and blood coagulation factor. Some of these proteins exhibit types of enzymatic activities. However, other items are proteins with no enzymatic activity. Materials and Methods: In order to study the mechanism and effect of the venom on human plasma proteins, the present study has evaluated the effect of crude venom and all fractions. A procoagulant factor (prothrombin activator) was isolated from the venom of the Iranian snake Echis carinatus with a combination of gel filtration (Sephadex G-75), ion-exchange chromatography (DEAE- Sepharose) and reverse phase HPLC. Furthermore, proteolytic activity of the crude venom and all fractions on blood coagulation factors such as prothrombin time (PT) was studied. Results: In the present study, the PT test was reduced from 13.4 s to 8.6 s when human plasma was treated with crude venom (concentraion of venom was 1 mg/ml). The purified procoagulant factor revealed a single protein band in SDS polyacrylamide electrophoresis under reducing conditions and its molecular weight was estimated at about 65 kDa. A single-band protein showed fragment patterns similar to those generated by the group A prothrombin activators, which convert prothrombin into meizothrombin independent of the prothrombinase complex. Conclusion: This study showed that the fraction which separated from Iranian snake Echis carinatus venom can be a prothrombin activators. It can be concluded that this fraction is a procoagulant factor. PMID:24494066

  4. [Proteins influencing the blood coagulation].

    PubMed

    Alberio, Lorenzo

    2011-11-01

    This review describes some natural proteins, which can be employed, either as factor concentrates derived from human plasma or as recombinant drug, to modulate the coagulation system. I will address some biochemical characteristics and the physiological role of von Willebrand factor, the coagulation factors of the extrinsic and intrinsic pathways, and the physiological anticoagulant protein C. In addition, I will detail the pharmacological compounds, which are available for influencing or substituting the coagulation proteins: desmopressin (DDAVP), single coagulation factor concentrates, prothrombin complex concentrates, and protein C concentrate. In particular, I will address some treatment topics of general medical interest, such as the treatment of massive bleeding, the correction of the coagulopathy induced by vitamin K-antagonists in patients with cerebral haemorrhage, and of the coagulopathy of meningococcemia. Finally, I will describe some properties and practical clinical applications of the recombinant anticoagulans lepirudin and bivalirudin, which are derived from hirudin, the natural anticoagulant of the medical leech.

  5. Isolation and properties of a blood coagulation factor X activator from the venom of king cobra (Ophiophagus hannah).

    PubMed

    Lee, W H; Zhang, Y; Wang, W Y; Xiong, Y L; Gao, R

    1995-10-01

    A specific blood coagulation factor X activator was purified from the venom of Ophiophagus hannah by gel filtration and two steps of FPLC Mono-Q column ion-exchange chromatography. It showed a single protein band both in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and alkaline polyacrylamide gel electrophoresis. The mol. wt was estimated to be 62,000 in non-reducing conditions and 64,500 in reducing conditions by SDS-PAGE. The isoelectric point was found to be pH 5.6. The enzyme had weak amidolytic activities toward CBS 65-25, but it showed no activities on S-2266, S-2302, thrombin substrate S-2238, plasmin substrate S-2251 or factor Xa substrate S-2222. It had no arginine esterase activity toward substrate benzoylarginine ethylester (BAEE). The enzyme activated factor X in vitro and the effect was absolutely Ca2+ dependent, with a Hill coefficient of 6.83. It could not activate prothrombin nor had any effect on fibrinogen and thus appeared to act specifically on factor X. The procoagulant activity of the enzyme was almost completely inhibited by serine protease inhibitors like PMSF, TPCK and soybean trypsin inhibitor; partially inhibited by L-cysteine. Metal chelator EDTA did not inhibit its procoagulant activity. These results suggest that the factor X activator from O. hannah venom is a serine protease.

  6. Effect of nano-scale curvature on the intrinsic blood coagulation system.

    PubMed

    Kushida, Takashi; Saha, Krishnendu; Subramani, Chandramouleeswaran; Nandwana, Vikas; Rotello, Vincent M

    2014-11-01

    The intrinsic coagulation activity of silica nanoparticles strongly depends on their surface curvature. Nanoparticles with higher surface curvature do not denature blood coagulation factor XII on its surface, providing a coagulation 'silent' surface, while nanoparticles with lower surface curvature show denaturation and concomitant coagulation.

  7. [Plasma blood coagulation in mammals (domestic and zoo animals). Experience with screening tests and determinations of individual factor activities].

    PubMed

    Lutze, G; Lutze, G; Kutschmann, K; Wiens, L

    2007-08-01

    Plasma coagulation in mammals shows an essentially uniform structure. Differences are in species specific composition and quantity of coagulation factors. Many of the coagulation disorders occurring in humans have been observed in other mammals. Almost all the coagulation studies performed to date have been in domestic animals. For the majority of mammalian species, e.g. zoo animals, therefore, we have either no data at all or only isolated results. The methods used for coagulation testing in veterinary medicine have not yet been standardized. The significance and informative value of the screening tests are limited in animals compared with humans. The activities of individual factors in animals are determined by coagulometric tests. The results can be determined in relation to the activity in humans with the help of a human normal plasma or in relation to the activity of the respective animal with the help of a normal plasma from the same species. The problem is the parallelity of the dilution curves used as reference curves. The coagulation factor activities given for mammals usually differ more or less markedly from those in humans.

  8. Quartz crystal microbalance-with dissipation monitoring (QCM-D) for real time measurements of blood coagulation density and immune complement activation on artificial surfaces.

    PubMed

    Andersson, Marcus; Andersson, Jonas; Sellborn, Anders; Berglin, Mattias; Nilsson, Bo; Elwing, Hans

    2005-07-15

    A recently developed variant of quartz crystal microbalance (QCM) called QCM-with dissipation monitoring (QCM-D) allows simultaneous and simple measurements of changes in adsorbed mass as well as the viscoelastic property (D-factor) of deposited protein layers on the sensor surface. We have taken the QCM-D technology a step further and demonstrated its advantages in the study of protein assembly as a consequence of surface induced immune complement activation, or contact activated blood coagulation. In the present study we have continued our QCM-D investigations of surface assembly of fibrin clot formation and complement activation and incubated differently modified quartz sensor surfaces in blood plasma and sera. Polymer surfaces used were spin-coated polyethylene, poly(ethylene terephtalate), poly(methylmetacrylate) and poly(dimethylsiloxane). Also used were sputtered titanium and heparin grafted surfaces. In this investigation we found that we could describe the surface induced coagulation with four independent parameters: (1) Time of onset of coagulation, (2) fibrin deposition rate, (3) total frequency shift at stable plateau, and (4) fibrin clot density. The most important finding was that the blood plasma clot density can be assessed with the use of D determinations and that the clot density varied significantly with the chemical composition of the surface. However, the D-factor did not give any new analytical information about the possible complement activation mechanisms. Nevertheless, the QCM-D was found to be a reliable tool for the analysis of surface induced complement activation. We also compared the QCM-D technique with traditional enzyme immuno assay (EIA) measurements of soluble products from the surface activation of the complement and coagulation systems. We found that the results from EIA and QCM-D measurements corresponded well for the complement activation but not for the coagulation, probably due to the biological complexity of the coagulation

  9. Magnetic particle imaging of blood coagulation

    NASA Astrophysics Data System (ADS)

    Murase, Kenya; Song, Ruixiao; Hiratsuka, Samu

    2014-06-01

    We investigated the feasibility of visualizing blood coagulation using a system for magnetic particle imaging (MPI). A magnetic field-free line is generated using two opposing neodymium magnets and transverse images are reconstructed from the third-harmonic signals received by a gradiometer coil, using the maximum likelihood-expectation maximization algorithm. Our MPI system was used to image the blood coagulation induced by adding CaCl2 to whole sheep blood mixed with magnetic nanoparticles (MNPs). The "MPI value" was defined as the pixel value of the transverse image reconstructed from the third-harmonic signals. MPI values were significantly smaller for coagulated blood samples than those without coagulation. We confirmed the rationale of these results by calculating the third-harmonic signals for the measured viscosities of samples, with an assumption that the magnetization and particle size distribution of MNPs obey the Langevin equation and log-normal distribution, respectively. We concluded that MPI can be useful for visualizing blood coagulation.

  10. Magnetic particle imaging of blood coagulation

    SciTech Connect

    Murase, Kenya Song, Ruixiao; Hiratsuka, Samu

    2014-06-23

    We investigated the feasibility of visualizing blood coagulation using a system for magnetic particle imaging (MPI). A magnetic field-free line is generated using two opposing neodymium magnets and transverse images are reconstructed from the third-harmonic signals received by a gradiometer coil, using the maximum likelihood-expectation maximization algorithm. Our MPI system was used to image the blood coagulation induced by adding CaCl{sub 2} to whole sheep blood mixed with magnetic nanoparticles (MNPs). The “MPI value” was defined as the pixel value of the transverse image reconstructed from the third-harmonic signals. MPI values were significantly smaller for coagulated blood samples than those without coagulation. We confirmed the rationale of these results by calculating the third-harmonic signals for the measured viscosities of samples, with an assumption that the magnetization and particle size distribution of MNPs obey the Langevin equation and log-normal distribution, respectively. We concluded that MPI can be useful for visualizing blood coagulation.

  11. Thromboplastin immobilized on polystyrene surface exhibits kinetic characteristics close to those for the native protein and activates in vitro blood coagulation similarly to thromboplastin on fibroblasts.

    PubMed

    Fadeeva, O A; Panteleev, M A; Karamzin, S S; Balandina, A N; Smirnov, I V; Ataullakhanov, F I

    2010-06-01

    A method for transmembrane protein thromboplastin (tissue factor) immobilization on polystyrene surface is described. Tissue factor is the main activating factor launching the blood coagulation process. It is a cofactor of factor VIIa, the first protease in the cascade of coagulation reactions. The proposed method preserves kinetic characteristics specific for native tissue factor on the fibroblast surface. The kinetics of binding to factor VIIa and enzymic activity of the formed complex follow Michaelis-Menten kinetics, which is also characteristic of native complex. A small difference is that dissociation constant for tissue factor immobilized on polystyrene surface exceeds 2.7-fold that for native factor. The proposed technique of immobilization provides for protein density on the activating surface corresponding to the tissue factor density on the fibroblast surface. The immobilized tissue factor can be used to activate blood coagulation in methods simulating spatial dynamics of in vitro clot growth. Investigation in this direction will make it possible to register both hypo- and hypercoagulation states of the system. This approach is advantageous over traditional methods of estimation of the coagulation system conditions, which mainly register only hypocoagulation. Investigation of the storage time has shown that activators containing immobilized tissue factor can be stored and used during for at least 100 days in the method studying spatial dynamics of fibrin clot formation.

  12. Principles of dielectric blood coagulometry as a comprehensive coagulation test.

    PubMed

    Hayashi, Yoshihito; Brun, Marc-Aurèle; Machida, Kenzo; Nagasawa, Masayuki

    2015-10-01

    Dielectric blood coagulometry (DBCM) is intended to support hemostasis management by providing comprehensive information on blood coagulation from automated, time-dependent measurements of whole blood dielectric spectra. We discuss the relationship between the series of blood coagulation reactions, especially the aggregation and deformation of erythrocytes, and the dielectric response with the help of clot structure electron microscope observations. Dielectric response to the spontaneous coagulation after recalcification presented three distinct phases that correspond to (P1) rouleau formation before the onset of clotting, (P2) erythrocyte aggregation and reconstitution of aggregates accompanying early fibrin formation, and (P3) erythrocyte shape transformation and/or structure changes within aggregates after the stable fibrin network is formed and platelet contraction occurs. Disappearance of the second phase was observed upon addition of tissue factor and ellagic acid for activation of extrinsic and intrinsic pathways, respectively, which is attributable to accelerated thrombin generation. A series of control experiments revealed that the amplitude and/or quickness of dielectric response reflect platelet function, fibrin polymerization, fibrinolysis activity, and heparin activity. Therefore, DBCM sensitively measures blood coagulation via erythrocytes aggregation and shape changes and their impact on the dielectric permittivity, making possible the development of the battery of assays needed for comprehensive coagulation testing.

  13. Principles of dielectric blood coagulometry as a comprehensive coagulation test.

    PubMed

    Hayashi, Yoshihito; Brun, Marc-Aurèle; Machida, Kenzo; Nagasawa, Masayuki

    2015-10-01

    Dielectric blood coagulometry (DBCM) is intended to support hemostasis management by providing comprehensive information on blood coagulation from automated, time-dependent measurements of whole blood dielectric spectra. We discuss the relationship between the series of blood coagulation reactions, especially the aggregation and deformation of erythrocytes, and the dielectric response with the help of clot structure electron microscope observations. Dielectric response to the spontaneous coagulation after recalcification presented three distinct phases that correspond to (P1) rouleau formation before the onset of clotting, (P2) erythrocyte aggregation and reconstitution of aggregates accompanying early fibrin formation, and (P3) erythrocyte shape transformation and/or structure changes within aggregates after the stable fibrin network is formed and platelet contraction occurs. Disappearance of the second phase was observed upon addition of tissue factor and ellagic acid for activation of extrinsic and intrinsic pathways, respectively, which is attributable to accelerated thrombin generation. A series of control experiments revealed that the amplitude and/or quickness of dielectric response reflect platelet function, fibrin polymerization, fibrinolysis activity, and heparin activity. Therefore, DBCM sensitively measures blood coagulation via erythrocytes aggregation and shape changes and their impact on the dielectric permittivity, making possible the development of the battery of assays needed for comprehensive coagulation testing. PMID:26368847

  14. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress.

    PubMed

    Rukhlenko, Oleksii S; Dudchenko, Olga A; Zlobina, Ksenia E; Guria, Georgy Th

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines.

  15. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress

    PubMed Central

    Rukhlenko, Oleksii S.; Dudchenko, Olga A.; Zlobina, Ksenia E.; Guria, Georgy Th.

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines. PMID:26222505

  16. Effect of nano-scale curvature on the intrinsic blood coagulation system

    NASA Astrophysics Data System (ADS)

    Kushida, Takashi; Saha, Krishnendu; Subramani, Chandramouleeswaran; Nandwana, Vikas; Rotello, Vincent M.

    2014-11-01

    The intrinsic coagulation activity of silica nanoparticles strongly depends on their surface curvature. Nanoparticles with higher surface curvature do not denature blood coagulation factor XII on its surface, providing a coagulation `silent' surface, while nanoparticles with lower surface curvature show denaturation and concomitant coagulation.The intrinsic coagulation activity of silica nanoparticles strongly depends on their surface curvature. Nanoparticles with higher surface curvature do not denature blood coagulation factor XII on its surface, providing a coagulation `silent' surface, while nanoparticles with lower surface curvature show denaturation and concomitant coagulation. Electronic supplementary information (ESI) available: Physical properties and scanning electron micrographs (SEM) of silica NPs, intrinsic coagulation activity after 3 h. See DOI: 10.1039/c4nr04128c

  17. [Regulation of Membrane-Dependent Reactions of Blood Coagulation].

    PubMed

    Podoplelova, N A; Kotova, Y N; Lipets, E N; Ataullakhanov, F I; Panteleev, M A

    2015-01-01

    All major coagulation reactions do not occurs in blood plasma itself, these processes are actually two-dimensional reactions localized to thephospholipid membranes. Almost all blood cells, lipoproteins, and microparticles provide assembly of protein complexes. A central role among them are played by platelets and platelet-derived microparticles. On their membranes occurs the most important coagulation reactions such as activation of prothrombin by prothrombin complex, activation of factor X by complexes intrinsic and extrinsic tenase. This reactions are important for processes activation of the contact path coagulation, activation factor XI by thrombin, appearance of enzymatic activity of factor VIIa etc. This review is focused on the membrane-dependent reactions, here are discussed mechanisms and regulation these reactions and the possible prospects of the study.

  18. Blood coagulation as an intrinsic pathway for proinflammation: a mini review.

    PubMed

    Chu, Arthur J

    2010-03-01

    Blood coagulation could be recognized as intrinsic inflammation. The coagulant mediators (FVIIa, FXa, thrombin (FIIa), FXIIa) and fibrin(ogen) activate cellular signaling, eliciting the production of cytokines, chemokines, growth factors, and other proinflammatory mediators. Hypercoagulability with elevated coagulant mediators would certainly trigger hyper-inflammatory state not to mention about the direct hypercoagulable actions on thrombosis, and platelet and complement activations, all of which contribute to inflammatory events. Furthermore, anticoagulant's anti-inflammatory effects readily reinforce the proposal that blood coagulation results in inflammation. The observations on protease activated receptor (PAR) activation and PAR antagonists modulating inflammation are also in line with the concept of coagulation-dependent inflammation.

  19. Comparison of the blood coagulation profiles of ferrets and rats.

    PubMed

    Takahashi, Saya; Hirai, Norihiko; Shirai, Mitsuyuki; Ito, Katsuaki; Asai, Fumitoshi

    2011-07-01

    The aim of this study was to examine the blood coagulation profiles of ferrets and compare them with those of rats. The ferret activated partial thromboplastin time (aPTT) was slightly longer than the rat aPTT. In contrast, the ferret prothrombin time and thrombin time were profoundly shorter than the corresponding rat values. The fibrinogen level in ferret plasma was 2 times higher than that in rats. Heparin prolonged all blood coagulation times in a concentration-dependent manner in both ferret and rat plasma. A significantly (P<0.01) higher concentration of heparin was required to double the aPTT in ferrets than rats. These blood coagulation data for ferrets will be useful in experimental animal studies.

  20. Acoustic determination of early stages of intravascular blood coagulation.

    PubMed

    Uzlova, Svetlana G; Guria, Konstantin G; Guria, Georgy Th

    2008-10-13

    The blood coagulation system (BCS) is a complex biological system playing a principal role in the maintenance of haemostasis. Insufficient activity of the BCS may lead to bleeding and blood loss (e.g. in the case of haemophilia). On the other hand, excessive activity may cause intravascular blood coagulation, thromboses and embolization. Most of the methods currently used for BCS monitoring suffer from the major disadvantage of being invasive. The purpose of the present work is to demonstrate the feasibility of using ultrasonic methods for non-invasive registration of the early stages of blood coagulation processes in intensive flows. With this purpose, a special experimental set-up was designed, facilitating the simultaneous detection of optical and acoustic signals during the clotting process. It was shown that (i) as microemboli appear in the flow during the early stage of blood coagulation, the intensity of the Doppler signal increases twofold, and (ii) microemboli formation in the early stages of blood clotting always reveals itself through an acoustic contrast. Both of these effects are well defined, so we hope that they may be used for non-invasive BCS monitoring in clinical practice.

  1. Oxidation inhibits iron-induced blood coagulation.

    PubMed

    Pretorius, Etheresia; Bester, Janette; Vermeulen, Natasha; Lipinski, Boguslaw

    2013-01-01

    Blood coagulation under physiological conditions is activated by thrombin, which converts soluble plasma fibrinogen (FBG) into an insoluble clot. The structure of the enzymatically-generated clot is very characteristic being composed of thick fibrin fibers susceptible to the fibrinolytic degradation. However, in chronic degenerative diseases, such as atherosclerosis, diabetes mellitus, cancer, and neurological disorders, fibrin clots are very different forming dense matted deposits (DMD) that are not effectively removed and thus create a condition known as thrombosis. We have recently shown that trivalent iron (ferric ions) generates hydroxyl radicals, which subsequently convert FBG into abnormal fibrin clots in the form of DMDs. A characteristic feature of DMDs is their remarkable and permanent resistance to the enzymatic degradation. Therefore, in order to prevent thrombotic incidences in the degenerative diseases it is essential to inhibit the iron-induced generation of hydroxyl radicals. This can be achieved by the pretreatment with a direct free radical scavenger (e.g. salicylate), and as shown in this paper by the treatment with oxidizing agents such as hydrogen peroxide, methylene blue, and sodium selenite. Although the actual mechanism of this phenomenon is not yet known, it is possible that hydroxyl radicals are neutralized by their conversion to the molecular oxygen and water, thus inhibiting the formation of dense matted fibrin deposits in human blood.

  2. Kinetics of the Factor XIa catalyzed activation of human blood coagulation Factor IX

    SciTech Connect

    Walsh, P.N.; Bradford, H.; Sinha, D.; Piperno, J.R.; Tuszynski, G.P.

    1984-05-01

    The kinetics of activation of human Factor IX by human Factor XIa was studied by measuring the release of a trichloroacetic acid-soluble tritium-labeled activation peptide from Factor IX. Initial rates of trichloroacetic acid-soluble /sup 3/H-release were linear over 10-30 min of incubation of Factor IX (88 nM) with CaCl/sub 2/ (5 mM) and with pure (greater than 98%) Factor XIa (0.06-1.3 nM), which was prepared by incubating human Factor XI with bovine Factor XIIa. Release of /sup 3/H preceded the appearance of Factor IXa activity, and the percentage of /sup 3/H released remained constant when the mole fraction of /sup 3/H-labeled and unlabeled Factor IX was varied and the total Factor IX concentration remained constant. A linear correlation (r greater than 0.98, P less than 0.001) was observed between initial rates of /sup 3/H-release and the concentration of Factor XIa, measured by chromogenic assay and by radioimmunoassay and added at a Factor IX:Factor XIa molar ratio of 70-5,600. Kinetic parameters, determined by Lineweaver-Burk analysis, include K/sub m/ (0.49 microM) of about five- to sixfold higher than the plasma Factor IX concentration, which could therefore regulate the reaction. The catalytic constant (k/sub cat/) (7.7/s) is approximately 20-50 times higher than that reported by Zur and Nemerson for Factor IX activation by Factor VIIa plus tissue factor. Therefore, depending on the relative amounts of Factor XIa and Factor VIIa generated in vivo and other factors which may influence reaction rates, these kinetic parameters provide part of the information required for assessing the relative contributions of the intrinsic and extrinsic pathways to Factor IX activation, and suggest that the Factor XIa catalyzed reaction is physiologically significant.

  3. Impaired Activity of Blood Coagulant Factor XIII in Patients with Necrotizing Enterocolitis.

    PubMed

    Tao, Guo-Zhong; Liu, Bo; Zhang, Rong; Liu, Gigi; Abdullah, Fizan; Harris, Mary Cay; Brandt, Mary L; Ehrenkranz, Richard A; Bowers, Corinna; Martin, Camilia R; Moss, R Lawrence; Sylvester, Karl G

    2015-01-01

    Necrotizing enterocolitis (NEC) is the most common gastrointestinal (GI) medical/surgical emergency of the newborn and a leading cause of preterm neonate morbidity and mortality. NEC is a challenge to diagnose since it often shares similar clinical features with neonatal sepsis. In the present study, plasma protein profiling was compared among NEC, sepsis and control cohorts using gel electrophoresis, immunoblot and mass spectrometry. We observed significant impairment in the formation of fibrinogen-γ dimers (FGG-dimer) in the plasma of newborns with NEC that could efficiently differentiate NEC and sepsis with a high level of sensitivity and specificity. Interestingly, the impaired FGG-dimer formation could be restored in NEC plasma by the addition of exogenous active factor XIII (FXIII). Enzymatic activity of FXIII was determined to be significantly lower in NEC subject plasma for crosslinking FGG when compared to sepsis. These findings demonstrate a potential novel biomarker and related biologic mechanism for diagnosing NEC, as well as suggest a possible therapeutic strategy. PMID:26277871

  4. Impaired Activity of Blood Coagulant Factor XIII in Patients with Necrotizing Enterocolitis.

    PubMed

    Tao, Guo-Zhong; Liu, Bo; Zhang, Rong; Liu, Gigi; Abdullah, Fizan; Harris, Mary Cay; Brandt, Mary L; Ehrenkranz, Richard A; Bowers, Corinna; Martin, Camilia R; Moss, R Lawrence; Sylvester, Karl G

    2015-08-17

    Necrotizing enterocolitis (NEC) is the most common gastrointestinal (GI) medical/surgical emergency of the newborn and a leading cause of preterm neonate morbidity and mortality. NEC is a challenge to diagnose since it often shares similar clinical features with neonatal sepsis. In the present study, plasma protein profiling was compared among NEC, sepsis and control cohorts using gel electrophoresis, immunoblot and mass spectrometry. We observed significant impairment in the formation of fibrinogen-γ dimers (FGG-dimer) in the plasma of newborns with NEC that could efficiently differentiate NEC and sepsis with a high level of sensitivity and specificity. Interestingly, the impaired FGG-dimer formation could be restored in NEC plasma by the addition of exogenous active factor XIII (FXIII). Enzymatic activity of FXIII was determined to be significantly lower in NEC subject plasma for crosslinking FGG when compared to sepsis. These findings demonstrate a potential novel biomarker and related biologic mechanism for diagnosing NEC, as well as suggest a possible therapeutic strategy.

  5. Impaired Activity of Blood Coagulant Factor XIII in Patients with Necrotizing Enterocolitis

    PubMed Central

    Tao, Guo-Zhong; Liu, Bo; Zhang, Rong; Liu, Gigi; Abdullah, Fizan; Harris, Mary Cay; Brandt, Mary L.; Ehrenkranz, Richard A.; Bowers, Corinna; Martin, Camilia R.; Moss, R. Lawrence; Sylvester, Karl G.

    2015-01-01

    Necrotizing enterocolitis (NEC) is the most common gastrointestinal (GI) medical/surgical emergency of the newborn and a leading cause of preterm neonate morbidity and mortality. NEC is a challenge to diagnose since it often shares similar clinical features with neonatal sepsis. In the present study, plasma protein profiling was compared among NEC, sepsis and control cohorts using gel electrophoresis, immunoblot and mass spectrometry. We observed significant impairment in the formation of fibrinogen-γ dimers (FGG-dimer) in the plasma of newborns with NEC that could efficiently differentiate NEC and sepsis with a high level of sensitivity and specificity. Interestingly, the impaired FGG-dimer formation could be restored in NEC plasma by the addition of exogenous active factor XIII (FXIII). Enzymatic activity of FXIII was determined to be significantly lower in NEC subject plasma for crosslinking FGG when compared to sepsis. These findings demonstrate a potential novel biomarker and related biologic mechanism for diagnosing NEC, as well as suggest a possible therapeutic strategy. PMID:26277871

  6. Markers of inflammation, activation of blood platelets and coagulation disorders in inflammatory bowel diseases.

    PubMed

    Matowicka-Karna, Joanna

    2016-04-13

    Inflammatory bowel disease (IBD) includes ulcerative colitis and Crohn's disease. It is a group of chronic disorders characterized by inflammation of the gastrointestinal track with unknown etiology. Currently applied biomarkers include CRP, ESR, pANCA, ASCA, and fecal calprotectin. The etiopathogenesis of IBD is multifactorial. In patients with IBD in inflamed alimentary tract mucosa the number of recruited monocytes and activated macrophages which are source of cytokines. In IBD, the exacerbation is accompanied by thrombocytosis. Platelets play a crucial role in the hemostasis and inflammatory response. Selectins, which regulates the hemostasis and inflammatory response, stimulates the secretion of many inflammatory mediators such as β-thromboglobuline, CD40L, fibrinogen, IL-1β, platelet factor-4. In the course of IBD the following changes are observed: an increase in the number of platelets (reactive thrombocytosis), PDW and PCT, reduction in MPV, increased production and excretion of granular content products (P-selectin, GP53, β-TG, PF-4, vWF, fibrinolytic inhibitors).

  7. Blood transfusion and coagulation management.

    PubMed

    Meier, Jens

    2016-09-01

    Despite impressive progress in surgical technique, aortic surgery is still associated with relatively high morbidity and mortality. One of the most important contributors to this phenomenon is the triad of bleeding, anemia, and transfusion. All three factors are known to influence the outcome of aortic surgery to a great extent. However, over the last few years a multidisciplinary, multimodal concept has been established, which enables the physician to avoid bleeding, anemia, and transfusion as much as possible. The concept of "patient blood management" combines several established measures with the potential to improve perioperative outcome. This chapter describes these measures with regard to aortic surgery and assesses their respective efficacy. PMID:27650346

  8. Positive charge of chitosan retards blood coagulation on chitosan films.

    PubMed

    He, Qing; Gong, Kai; Ao, Qiang; Ma, Tuo; Yan, Yufang; Gong, Yandao; Zhang, Xiufang

    2013-05-01

    In this study, a series of chitosan films with different protonation degrees were prepared by deacidification with NaOH aqueous or ethanol solutions. The films were then used as a model to investigate the effects of the positive charge of chitosan on blood coagulation. The results showed that the positive charge of chitosan acted as a double-edged sword, in that it promoted erythrocyte adhesion, fibrinogen adsorption, and platelet adhesion and activation, but inhibited activation of the contact system. In contrast to prevailing views, we found that the positive charge of chitosan retarded thrombin generation and blood coagulation on these films. At least two reasons were responsible for this phenomenon. First, the positive charge inhibited the contact activation, and second, the positive charge could not significantly promote the activation of non-adherent platelets in the bulk phase during the early stage of coagulation. The present findings improve our understanding of the events leading to blood coagulation on chitosan films, which will be useful for the future development of novel chitosan-based hemostatic devices.

  9. Fibrinolysis and the control of blood coagulation.

    PubMed

    Chapin, John C; Hajjar, Katherine A

    2015-01-01

    Fibrin plays an essential role in hemostasis as both the primary product of the coagulation cascade and the ultimate substrate for fibrinolysis. Fibrinolysis efficiency is greatly influenced by clot structure, fibrinogen isoforms and polymorphisms, the rate of thrombin generation, the reactivity of thrombus-associated cells such as platelets, and the overall biochemical environment. Regulation of the fibrinolytic system, like that of the coagulation cascade, is accomplished by a wide array of cofactors, receptors, and inhibitors. Fibrinolytic activity can be generated either on the surface of a fibrin-containing thrombus, or on cells that express profibrinolytic receptors. In a widening spectrum of clinical disorders, acquired and congenital defects in fibrinolysis contribute to disease morbidity, and new assays of global fibrinolysis now have potential predictive value in multiple clinical settings. Here, we summarize the basic elements of the fibrinolytic system, points of interaction with the coagulation pathway, and some recent clinical advances.

  10. Fibrinolysis and the control of blood coagulation

    PubMed Central

    Chapin, John C.; Hajjar, Katherine A.

    2014-01-01

    Fibrin plays an essential role in hemostasis as both the primary product of the coagulation cascade and the ultimate substrate for fibrinolysis. Fibrinolysis efficiency is greatly influenced by clot structure, fibrinogen isoforms and polymorphisms, the rate of thrombin generation, the reactivity of thrombus-associated cells such as platelets, and the overall biochemical environment. Regulation of the fibrinolytic system, like that of the coagulation cascade, is accomplished by a wide array of cofactors, receptors, and inhibitors. Fibrinolytic activity can be generated either on the surface of a fibrin-containing thrombus, or on cells that express profibrinolytic receptors. In a widening spectrum of clinical disorders, acquired and congenital defects in fibrinolysis contribute to disease morbidity, and new assays of global fibrinolysis now have potential predictive value in multiple clinical settings. Here, we summarize the basic elements of the fibrinolytic system, points of interaction with the coagulation pathway, and some recent clinical advances. PMID:25294122

  11. Spatial localization of bacteria controls coagulation of human blood by 'quorum acting'.

    PubMed

    Kastrup, Christian J; Boedicker, James Q; Pomerantsev, Andrei P; Moayeri, Mahtab; Bian, Yao; Pompano, Rebecca R; Kline, Timothy R; Sylvestre, Patricia; Shen, Feng; Leppla, Stephen H; Tang, Wei-Jen; Ismagilov, Rustem F

    2008-12-01

    Blood coagulation often accompanies bacterial infections and sepsis and is generally accepted as a consequence of immune responses. Though many bacterial species can directly activate individual coagulation factors, they have not been shown to directly initiate the coagulation cascade that precedes clot formation. Here we demonstrated, using microfluidics and surface patterning, that the spatial localization of bacteria substantially affects coagulation of human and mouse blood and plasma. Bacillus cereus and Bacillus anthracis, the anthrax-causing pathogen, directly initiated coagulation of blood in minutes when bacterial cells were clustered. Coagulation of human blood by B. anthracis required secreted zinc metalloprotease InhA1, which activated prothrombin and factor X directly (not via factor XII or tissue factor pathways). We refer to this mechanism as 'quorum acting' to distinguish it from quorum sensing--it does not require a change in gene expression, it can be rapid and it can be independent of bacterium-to-bacterium communication.

  12. Effect of Chronic Blood Transfusion on Biomarkers of Coagulation Activation and Thrombin Generation in Sickle Cell Patients at Risk for Stroke

    PubMed Central

    Hyacinth, Hyacinth I.; Adams, Robert J.; Greenberg, Charles S.; Voeks, Jenifer H.; Hill, Allyson; Hibbert, Jacqueline M.; Gee, Beatrice E.

    2015-01-01

    Hypercoagulability in sickle cell disease (SCD) is associated with multiple SCD phenotypes, association with stroke risk has not been well described. We hypothesized that serum levels of biomarkers of coagulation activation correlate with high transcranial Doppler ultrasound velocity and decreases with blood transfusion therapy in SCD patients. Stored serum samples from subjects in the Stroke Prevention in Sickle Cell Anemia (STOP) trial were analyzed using ELISA and protein multiplexing techniques. 40 subjects from each treatment arm (Standard Care [SC] and Transfusion [Tx]) at three time points—baseline, study exit and one year post-trial and 10 each of age matched children with SCD but normal TCD (SNTCD) and with normal hemoglobin (HbAA) were analyzed. At baseline, median vWF, TAT and D-dimer levels were significantly higher among STOP subjects than either HbAA or SNTCD. At study exit, median hemoglobin level was significantly higher while median TCD velocity was significantly lower in Tx compared to SC subjects. Median vWF (409.6 vs. 542.9 μg/ml), TAT (24.8 vs. 40.0 ng/ml) and D-dimer (9.2 vs. 19.1 μg/ml) levels were also significantly lower in the Tx compared to the SC group at study exit. Blood levels of biomarkers coagulation activation/thrombin generation correlated positively with TCD velocity and negatively with number of blood transfusions. Biomarkers of coagulation activation/thrombin generation were significantly elevated in children with SCD, at high risk for stroke. Reduction in levels of these biomarkers correlated with reduction in stroke risk (lower TCD velocity), indicating a possible role for hypercoagulation in SCD associated stroke. PMID:26305570

  13. Blood coagulation and platelet adhesion on polyaniline films.

    PubMed

    Humpolíček, Petr; Kuceková, Zdenka; Kašpárková, Věra; Pelková, Jana; Modic, Martina; Junkar, Ita; Trchová, Miroslava; Bober, Patrycja; Stejskal, Jaroslav; Lehocký, Marián

    2015-09-01

    Polyaniline is a promising conducting polymer with still increasing application potential in biomedicine. Its surface modification can be an efficient way how to introduce desired functional groups and to control its properties while keeping the bulk characteristics of the material unchanged. The purpose of the study was to synthetize thin films of pristine conducting polyaniline hydrochloride, non-conducting polyaniline base and polyaniline modified with poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA) and investigate chosen parameters of their hemocompatibility. The modification was performed either by introduction of PAMPSA during the synthesis or by reprotonation of polyaniline base. The polyaniline hydrochloride and polyaniline base had no impact on blood coagulation and platelet adhesion. By contrast, the polyaniline reprotonated with PAMPSA completely hindered coagulation thanks to its interaction with coagulation factors Xa, Va and IIa. The significantly lower platelets adhesion was also found on this surface. Moreover, this film maintains its conductivity at pH of 6, which is an improvement in comparison with standard polyaniline hydrochloride losing most of its conductivity at pH of 4. Polyaniline film with PAMPSA introduced during synthesis had an impact on platelet adhesion but not on coagulation. The combined conductivity, anticoagulation activity, low platelet adhesion and improved conductivity at pH closer to physiological, open up new possibilities for application of polyaniline reprotonated by PAMPSA in blood-contacting devices, such as catheters or blood vessel grafts.

  14. Blood coagulation and platelet adhesion on polyaniline films.

    PubMed

    Humpolíček, Petr; Kuceková, Zdenka; Kašpárková, Věra; Pelková, Jana; Modic, Martina; Junkar, Ita; Trchová, Miroslava; Bober, Patrycja; Stejskal, Jaroslav; Lehocký, Marián

    2015-09-01

    Polyaniline is a promising conducting polymer with still increasing application potential in biomedicine. Its surface modification can be an efficient way how to introduce desired functional groups and to control its properties while keeping the bulk characteristics of the material unchanged. The purpose of the study was to synthetize thin films of pristine conducting polyaniline hydrochloride, non-conducting polyaniline base and polyaniline modified with poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA) and investigate chosen parameters of their hemocompatibility. The modification was performed either by introduction of PAMPSA during the synthesis or by reprotonation of polyaniline base. The polyaniline hydrochloride and polyaniline base had no impact on blood coagulation and platelet adhesion. By contrast, the polyaniline reprotonated with PAMPSA completely hindered coagulation thanks to its interaction with coagulation factors Xa, Va and IIa. The significantly lower platelets adhesion was also found on this surface. Moreover, this film maintains its conductivity at pH of 6, which is an improvement in comparison with standard polyaniline hydrochloride losing most of its conductivity at pH of 4. Polyaniline film with PAMPSA introduced during synthesis had an impact on platelet adhesion but not on coagulation. The combined conductivity, anticoagulation activity, low platelet adhesion and improved conductivity at pH closer to physiological, open up new possibilities for application of polyaniline reprotonated by PAMPSA in blood-contacting devices, such as catheters or blood vessel grafts. PMID:26119372

  15. Thymoquinone Modulates Blood Coagulation in Vitro via Its Effects on Inflammatory and Coagulation Pathways

    PubMed Central

    Muralidharan-Chari, Vandhana; Kim, Jaehan; Abuawad, Ahlam; Naeem, Mubeena; Cui, Huadong; Mousa, Shaker A.

    2016-01-01

    Thymoquinone (THQ) is a major component of black seeds. Given that both THQ and black seeds exhibit anti-cancer and anti-inflammatory activities, we hypothesized that THQ will affect cancer-associated thrombosis (CAT), which is primarily triggered by tissue factor (TF) and inflammation. The effect of both black seed-extracted and purchased (“pure”) THQ on normal blood coagulation was tested with in vitro thromboelastography (TEG) and activated partial thromboplastin time (aPTT) coagulation assays. The effect of pure THQ on CAT was tested with aPTT assay using pancreatic cancer cell lines that are either positive or negative for TF, and with TEG assay using lipopolysaccharide as an inflammatory trigger. Additionally, the direct effect of THQ on the inactivation of factors IIa and Xa was assessed. Since TNF-α facilitates crosstalk between inflammation and thrombosis by triggering the NF-κB pathway, we tested THQ’s ability to interfere with this communication with a luciferase assay. Both extracted and pure THQ had minimal effects on normal blood coagulation. Pure THQ reversed CAT initiated by both TF and inflammation to basal levels (p < 0.001). Mechanistically, while THQ had minimal to no effect on factor IIa and Xa inactivation, it strongly reduced the effects of TNF-α on NF-κB elements (p < 0.001). THQ has a minimal effect on basal coagulation and can reverse CAT in vitro, possibly by interfering with the crosstalk between inflammation and coagulation. This study suggests the utility of THQ as a preventative anticoagulant and/or as a supplement to existing chemotherapies and anticoagulant therapies. PMID:27043539

  16. Thymoquinone Modulates Blood Coagulation in Vitro via Its Effects on Inflammatory and Coagulation Pathways.

    PubMed

    Muralidharan-Chari, Vandhana; Kim, Jaehan; Abuawad, Ahlam; Naeem, Mubeena; Cui, Huadong; Mousa, Shaker A

    2016-01-01

    Thymoquinone (THQ) is a major component of black seeds. Given that both THQ and black seeds exhibit anti-cancer and anti-inflammatory activities, we hypothesized that THQ will affect cancer-associated thrombosis (CAT), which is primarily triggered by tissue factor (TF) and inflammation. The effect of both black seed-extracted and purchased ("pure") THQ on normal blood coagulation was tested with in vitro thromboelastography (TEG) and activated partial thromboplastin time (aPTT) coagulation assays. The effect of pure THQ on CAT was tested with aPTT assay using pancreatic cancer cell lines that are either positive or negative for TF, and with TEG assay using lipopolysaccharide as an inflammatory trigger. Additionally, the direct effect of THQ on the inactivation of factors IIa and Xa was assessed. Since TNF-α facilitates crosstalk between inflammation and thrombosis by triggering the NF-κB pathway, we tested THQ's ability to interfere with this communication with a luciferase assay. Both extracted and pure THQ had minimal effects on normal blood coagulation. Pure THQ reversed CAT initiated by both TF and inflammation to basal levels (p < 0.001). Mechanistically, while THQ had minimal to no effect on factor IIa and Xa inactivation, it strongly reduced the effects of TNF-α on NF-κB elements (p < 0.001). THQ has a minimal effect on basal coagulation and can reverse CAT in vitro, possibly by interfering with the crosstalk between inflammation and coagulation. This study suggests the utility of THQ as a preventative anticoagulant and/or as a supplement to existing chemotherapies and anticoagulant therapies. PMID:27043539

  17. Blood plasma coagulation studied by surface plasmon resonance

    NASA Astrophysics Data System (ADS)

    Vikinge, Trine P.; Hansson, Kenny M.; Benesch, Johan; Johansen, Knut; Ranby, Mats; Lindahl, Tomas L.; Liedberg, Bo; Lundstoem, Ingemar; Tengvall, Pentti

    2000-01-01

    A surface plasmon resonance (SPR) apparatus was used to investigate blood plasma coagulation in real time as a function of thromboplastin and heparin concentrations. The response curves were analyzed by curve fitting to a sigmoid curve equation, followed by extraction of the time constant. Clotting activation by thromboplastin resulted in increased time constant, as compared to spontaneously clotted plasma, in a dose dependent way. Addition of heparin to the thromboplastin-activated plasma counteracted this effect. Atomic force microscopy (AFM) pictures of sensor surfaces dried after completed clotting, revealed differences in fibrin network structures as a function of thromboplastin concentration, and the fiber thickness increased with decreased thromboplastin concentration. The physical reason for the SPR signal observed is ambiguous and is therefore discussed. However, the results summarized in the plots and the fibrin network properties observed by AFM correlate well with present common methods used to analyze blood coagulation.

  18. Influence of Blood Lipids on Global Coagulation Test Results

    PubMed Central

    Kim, Jung-Ah; Kim, Ji-Eun; Song, Sang Hoon

    2015-01-01

    Background High levels of blood lipids have been associated with high levels of coagulation factors. We investigated whether blood lipids influence the results of global coagulation tests, including prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin generation assay (TGA). Methods PT, aPTT, and TGA, along with procoagulant and anticoagulant factors, were measured in 488 normal individuals. Vitamin K status was assessed with prothrombin-induced by vitamin K absence-II (PIVKA-II). Results The procoagulant factors II, VII, IX, X, and XI and anticoagulant factors protein C and protein S showed significant correlations with triglyceride, and the procoagulant factors II, V, VII, IX, X, XI, and XII and anticoagulant factors antithrombin and protein C correlated with total cholesterol. There were no correlations of blood lipid levels with PIVKA-II levels. Subjects with high triglyceride levels (≥200 mg/dL) showed shorter PT values than those with lower triglyceride levels. However, aPTT value was not changed in terms of blood lipid levels. In both 1 and 5 pM tissue factor-induced TGAs, subjects in the high-triglyceride or high-cholesterol groups (≥240 mg/dL) had high levels of lag time, time-to-peak, and endogenous thrombin potential. Total cholesterol was a significant determinant of PT and TGA values. Conclusion High blood lipids were related with increased coagulation activity in a normal population. Our findings are expected to help interpret the global coagulation test results in individuals with high lipid levels. PMID:25553275

  19. Influence of solar activity on fibrinolysis and fibrinogenolysis. [statistical correlation between solar flare and blood coagulation indices

    NASA Technical Reports Server (NTRS)

    Marchenko, V. I.

    1974-01-01

    During periods of high solar activity fibrinolysis and fibrinogenolysis are increased. A direct correlative relationship is established between the indices of fibrinolysis, fibrinogenolysis and solar flares which were recorded two days before the blood was collected for analysis.

  20. A Spatial-Temporal Model of Platelet Deposition and Blood Coagulation Under Flow

    NASA Astrophysics Data System (ADS)

    Leiderman Gregg, Karin; Fogelson, Aaron

    2009-11-01

    In the event of a vascular injury, a blood clot will form to prevent bleeding. This response involves two intertwined processes: platelet aggregation and coagulation. Activated platelets are critical to coagulation in that they provide localized reactive surfaces on which many of the coagulation reactions occur. The final product from the coagulation cascade directly couples the coagulation system to platelet aggregation by acting as a strong activator of platelets and cleaving blood-borne fibrinogen into fibrin which then forms a mesh to help stabilize platelet aggregates. Together, the fibrin mesh and the platelet aggregates comprise a blood clot, which in some cases, can grow to occlusive diameters. Transport of coagulation proteins to and from the vicinity of the injury is controlled largely by the dynamics of the blood flow. It is crucial to learn how blood flow affects the growth of clots, and how the growing masses, in turn, feed back and affect the fluid motion. We have developed the first spatial-temporal model of platelet deposition and blood coagulation under flow that includes detailed decriptions of the coagulation biochemistry, chemical activation and deposition of blood platelets, as well as the two-way interaction between the fluid dynamics and the growing platelet mass.

  1. Silica Nanoparticles Effects on Blood Coagulation Proteins and Platelets

    PubMed Central

    Gryshchuk, Volodymyr; Galagan, Natalya

    2016-01-01

    Interaction of nanoparticles with the blood coagulation is important prior to their using as the drug carriers or therapeutic agents. The aim of present work was studying of the primary effects of silica nanoparticles (SiNPs) on haemostasis in vitro. We studied the effect of SiNPs on blood coagulation directly estimating the activation of prothrombin and factor X and to verify any possible effect of SiNPs on human platelets. It was shown that SiNPs shortened coagulation time in APTT and PT tests and increased the activation of factor X induced by RVV possibly due to the sorption of intrinsic pathway factors on their surface. SiNPs inhibited the aggregation of platelet rich plasma induced by ADP but in the same time partially activated platelets as it was shown using flow cytometry. The possibility of SiNPs usage in nanomedicine is strongly dependant on their final concentration in bloodstream and the size of the particles that are used. However SiNPs are extremely promising as the haemostatic agents for preventing the blood loss after damage. PMID:26881078

  2. Bruises, blood coagulation tests and the battered child syndrome.

    PubMed

    Lee, A C

    2008-06-01

    Cutaneous bruises are a common symptom and a sign of injury and blood coagulation disorders in childhood. A carefully-taken history, coupled with a thorough physical examination, would lead to the diagnosis, or guide the clinician to the necessary laboratory investigations. Most children suffering from non-accidental injury can have their diagnosis established on clinical grounds alone and do not require laboratory investigation. An initial screening with full blood counts, prothrombin time and activated partial thromboplastin time will be adequate in most cases if laboratory investigation is indicated, but the clinician must be aware of the limitations of these tests. The finding of an abnormal coagulation test does not exclude child abuse as it can be a consequence of maltreatment, or the two conditions may coexist. Whenever necessary, the opinion of a haematologist should be sought in order to obtain an accurate diagnosis, which is essential for subsequent management and the prevention of further injury in the case of child abuse.

  3. Ca2+ switches the effect of PS-containing membranes on Factor Xa from activating to inhibiting: implications for initiation of blood coagulation.

    PubMed

    Koklic, Tilen; Majumder, Rinku; Lentz, Barry R

    2014-09-15

    Calcium (Ca2+) plays a pivotal role in cellular and organismal physiology. The Ca2+ ion has an intermediate protein-binding affinity and thus it can serve as an on/off switch in the regulation of different biochemical processes. The serum level of ionized Ca2+ is regulated with normal ionized Ca2+ being in the range 1.10-1.3 mM. Hypocalcaemia (free Ca2+<1.1 mM) in critically ill patients is commonly accompanied by haemostatic abnormalities, ranging from isolated thrombocytopenia to complex defects such as disseminated intravascular coagulation, commonly thought to be due to insufficient functioning of anticoagulation pathways. A small amount of fXa (Factor Xa) produced by Factor VIIa and exposed tissue factor is key to initiating blood coagulation by producing enough thrombin to induce the later stages of coagulation. fXa must bind to PS (phosphatidylserine)-containing membranes to produce thrombin at a physiologically significant rate. In the present study, we show that overall fXa activity on PS-containing membranes is sharply regulated by a 'Ca2+ switch' centred at 1.16 mM, below which fXa is active and above which fXa forms inactive dimers on PS-exposing membranes. Our data lead to a mathematical model that predicts the variation of fXa activity as a function of both Ca2+ and membrane concentrations. Because the critical Ca2+ concentration is at the lower end of the normal plasma ionized Ca2+ concentration range, we propose a new regulatory mechanism by which local Ca2+ concentration switches fXa from an intrinsically active form to a form requiring its cofactor [fVa (Factor Va)] to achieve significant activity.

  4. Ca2+ Switches the Effect of PS-containing Membranes on Factor Xa from Activating to Inhibiting: Implications for Initiation of Blood Coagulation

    PubMed Central

    Koklic, Tilen; Majumder, Rinku; Lentz, Barry R.

    2014-01-01

    Calcium (Ca2+) plays a pivotal role in cellular and organismal physiology. The Ca2+ ion has an intermediate protein-binding affinity, thus it can serve as an on/off switch in regulation of different biochemical processes. The serum level of ionized Ca2+ is regulated with normal ionized Ca2+ being in the range from 1.10 to 1.29 mM. Hypocalcaemia (free Ca2+ < 1.1mM) in critically ill patients is commonly accompanied by hemostatic abnormalities, ranging from isolated thrombocytopenia to complex defects such as disseminated intravascular coagulation, commonly thought to be due to insufficient functioning of anticoagulation pathways. A small amount of Factor Xa (fXa) produced by Factor VIIa and exposed tissue factor is key to initiating blood coagulation by producing enough thrombin to induce later stages of coagulation. FXa must bind to phosphatidylserine (PS)-containing membranes to produce thrombin at a physiologically significant rate. In this work, we show that overall fXa activity on PS-containing membranes is sharply regulated by a “Ca2+ switch” centered at 1.16 mM, below which fXa is active and above which fXa forms inactive dimers on PS-exposing membranes. Our data lead to a mathematical model that predicts the variation of fXa activity as a function of both calcium and membrane concentrations. Because the critical Ca2+ concentration is at the lower end of the normal plasma ionized Ca2+ concentration range, we propose a new regulatory mechanism by which local Ca2+ concentration switches fXa from an intrinsically active form to a form requiring its cofactor (fVa) to achieve significant activity. PMID:24920080

  5. Ovine blood: establishment of a list of reference values relevant for blood coagulation in sheep.

    PubMed

    Wilhelmi, Mathias H; Tiede, Andreas; Teebken, Omke E; Bisdas, Theodosios; Haverich, Axel; Mischke, Reinhard

    2012-01-01

    Ovine animal models are widely used to conduct preclinical studies, e.g., to evaluate cardiovascular prostheses intended to be applied in man. However, although analyzed in many of those studies, information about ovine blood reference values is scanty. The aim of this study is to establish a reference list of ovine blood parameters relevant for blood coagulation. A cohort of 47 mature ewes was evaluated. Parameters comprised the following: cells and cellular components-platelet, red, and white cell counts (including subsets), hemoglobin (Hb), hematocrit (HCT), mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV), and MCH concentration (MCHC); global tests of coagulation-prothrombin time (Quick's time) and activated partial thromboplastin time (aPTT); and parameters relevant for blood coagulation-fibrinogen, antithrombin (AT), and von Willebrand Factor. After explorative data analysis, a list of ovine reference values was established. Interestingly, a comparison with human reference values revealed some interspecies differences between sheep and man, i.e., much higher ovine ranges for some cell counts (neutrophils, lymphocytes, basophils, eosinophils, and platelets) but lower values for some other parameters (Hb, HCT, MCV, MCH, AT, and Quick's test). We established a reference list of ovine blood count and blood coagulation parameters. Because of some peculiarities of the ovine blood, this list may have implications for the interpretation of experimental data.

  6. Changes in the human blood coagulating system during prolonged hypokinesia

    NASA Technical Reports Server (NTRS)

    Filatova, L. M.; Anashkin, O. D.

    1978-01-01

    Changes in the coagulating system of the blood were studied in six subjects during prolonged hypokinesia. Thrombogenic properties of the blood rose in all cases on the 8th day. These changes are explained by stress reaction due to unusual conditions for a healthy person. Changes in the blood coagulating system in the group subjected to physical exercise and without it ran a practically parallel course. Apparently physical exercise is insufficient to prevent such changes that appear in the coagulating system of the blood during prolonged hypokinesia.

  7. Blood coagulation reactions on nanoscale membrane surfaces

    NASA Astrophysics Data System (ADS)

    Pureza, Vincent S.

    Blood coagulation requires the assembly of several membrane-bound protein complexes composed of regulatory and catalytic subunits. The biomembranes involved in these reactions not only provide a platform for these procoagulant proteins, but can also affect their function. Increased exposure of acidic phospholipids on the outer leaflet of the plasma membrane can dramatically modulate the catalytic efficiencies of such membrane-bound enzymes. Under physiologic conditions, however, these phospholipids spontaneously cluster into a patchwork of membrane microdomains upon which membrane binding proteins may preferentially assemble. As a result, the membrane composition surrounding these proteins is largely unknown. Through the development and use of a nanometer-scale bilayer system that provides rigorous control of the phospholipid membrane environment, I investigated the role of phosphatidylserine, an acidic phospholipid, in the direct vicinity (within nanometers) of two critical membrane-bound procoagulant protein complexes and their respective natural substrates. Here, I present how the assembly and function of the tissue factor˙factor VIIa and factor Va˙factor Xa complexes, the first and final cofactor˙enzyme complexes of the blood clotting cascade, respectively, are mediated by changes in their immediate phospholipid environments.

  8. [Influence of Gentiana lutea L extract on blood coagulation].

    PubMed

    Bakuridze, A D; Nikolaev, S M; Tsagarenshvili, N T; Kurdiani, N G; Mikaia, G A

    2009-01-01

    The dry extract from the terrestrial parts of Gentiana Lutea was received in accordance to the developed by us general technological scheme. Study of the pharmacological influence of obtained extract on the coagulating properties of blood revealed that after its per os instillation into experimental animals the time of the formation of active thromboplastin reliably increases, while the time of thrombin and fibrinous cluster formation is shortened in comparison with those indices in the animals, that did not receive phyto-preparation, at the same time morphological appearance of the peripheral blood remains unchanged. Dry extract of terrestrial parts of Gentiana Lutea prepared in accordance to the technology recommended by us, together with widely known pharmacological effects, is characterized with new activity - influence on haemostasis. Obtained preliminary data concerning influence of the extract on coagulation of the blood request further deep studies of its mechanism. Revealed new activity of the terrestrial parts of Gentiana Lutea and the studies of the mechanism of its activity will serve in future as a basis for the recommendation of its use in new nosology. Terrestrial parts of Gentiana lutea L. are proposed as an alternative of the underground parts of the plant. Alongside with that, it is expedient to continue the studies devoted to the development of the haemostatic remedies of plant origin with systemic and local action (sponges, films, skin glues) from terrestrial parts of Gentiana lutea L.

  9. Metals in airpollution particles decrease whole blood coagulation time

    EPA Science Inventory

    The mechanism underlying the pro-coagulative effect of air pollution particle exposure is not known. We tested the postulate that 1) the soluble fraction ofan air pollution particle can affect whole blood coagulation time and 2) metals included in the soluble fraction are respons...

  10. Effect of rivaroxaban on blood coagulation using the viscoelastic coagulation test ROTEM™.

    PubMed

    Casutt, M; Konrad, C; Schuepfer, G

    2012-11-01

    This study investigated the influence of the oral direct inhibitor of factor Xa rivaroxaban on blood coagulation measured by rotation thrombelastometry ROTEM™. Blood was obtained from 11 healthy male volunteers before and 2.5 h after oral administration of 10 mg rivaroxaban. In addition to standard coagulation tests clot formation was measured by ROTEM™ analyzing extrinsic (Extem) and intrinsic thrombelastometry (Intem). Significant differences to the baseline values were found in the Extem clotting time (Extem-CT, 58 ± 9 s and 87 ± 17 s, p < 0.01), Intem-CT (194 ± 26 s and 239 ± 43 s; p = 0.02), prothrombin time (PT, 86 ± 9% and 67 ± 7%; p < 0.01) and activated partial thromboplastin time (aPTT, 28 ± 1 s and 35 ± 2 s; p < 0.01). There was a low correlation between Extem-CT and PT as well as between Intem-CT and aPTT before and after rivaroxaban intake. The receiver operating characteristic curve (ROC) analysis determined aPTT to be the most appropriate parameter for the prediction of rivaroxaban-induced anticoagulation, Intem-CT and Extem-CT proved to be moderate tests and PT had no significance in the prediction of rivaroxaban-induced anticoagulation. Of utmost clinical importance was the fact that rivaroxaban treated patients could still show normal ROTEM™ values. Thus, ROTEM™ cannot be a suitable test method to exclude inhibition of blood coagulation by rivaroxaban.

  11. Numerical validation of a synthetic cell-based model of blood coagulation.

    PubMed

    Pavlova, J; Fasano, A; Janela, J; Sequeira, A

    2015-09-01

    In Fasano et al. (2012) a new reduced mathematical model for blood coagulation was proposed, incorporating biochemical and mechanical actions of blood flow and including platelets activity. The model was characterized by a considerable simplification of the differential system associated to the biochemical network and it incorporated the role of blood slip at the vessel wall as an extra source of activated platelets. The purpose of this work is to check the validity of the reduced mathematical model, using as a benchmark the model presented in Anand et al. (2008), and to investigate the importance of the blood slip velocity in the blood coagulation process.

  12. Tissue Factor, Blood Coagulation, and Beyond: An Overview

    PubMed Central

    Chu, Arthur J.

    2011-01-01

    Emerging evidence shows a broad spectrum of biological functions of tissue factor (TF). TF classical role in initiating the extrinsic blood coagulation and its direct thrombotic action in close relation to cardiovascular risks have long been established. TF overexpression/hypercoagulability often observed in many clinical conditions certainly expands its role in proinflammation, diabetes, obesity, cardiovascular diseases, angiogenesis, tumor metastasis, wound repairs, embryonic development, cell adhesion/migration, innate immunity, infection, pregnancy loss, and many others. This paper broadly covers seminal observations to discuss TF pathogenic roles in relation to diverse disease development or manifestation. Biochemically, extracellular TF signaling interfaced through protease-activated receptors (PARs) elicits cellular activation and inflammatory responses. TF diverse biological roles are associated with either coagulation-dependent or noncoagulation-mediated actions. Apparently, TF hypercoagulability refuels a coagulation-inflammation-thrombosis circuit in “autocrine” or “paracrine” fashions, which triggers a wide spectrum of pathophysiology. Accordingly, TF suppression, anticoagulation, PAR blockade, or general anti-inflammation offers an array of therapeutical benefits for easing diverse pathological conditions. PMID:21941675

  13. Effect of carryover of clot activators on coagulation tests during phlebotomy.

    PubMed

    Fukugawa, Yoko; Ohnishi, Hiroaki; Ishii, Takahiro; Tanouchi, Ayako; Sano, Junko; Miyawaki, Haruko; Kishino, Tomonori; Ohtsuka, Kouki; Yoshino, Hideaki; Watanabe, Takashi

    2012-06-01

    We investigated the effect of clot activators carried over from the serum tube on major coagulation tests during phlebotomy. First, blood specimens from 30 normal subjects were mixed with small amounts of fluid containing clot activators, and their effects on various coagulation tests were determined. Only the value of fibrin monomer complex displayed a remarkable change when thrombin-containing fluid was added to the blood specimens. Subsequently, 100 paired blood specimens (taken from 75 healthy volunteers and 25 patients taking warfarin) were collected in coagulation tubes before and after the serum tube using standard phlebotomy procedures. Various coagulation tests were performed to determine the effect of contamination of thrombin-containing blood on coagulation parameters. Differences between the 2 tubes were minimal but significant for some of the coagulation tests. Therefore, we conclude that the effect of clot activators in the serum tube on coagulation tests is minimal when standard phlebotomy procedures are used.

  14. Helical organization of blood coagulation factor VIII on lipid nanotubes.

    PubMed

    Miller, Jaimy; Dalm, Daniela; Koyfman, Alexey Y; Grushin, Kirill; Stoilova-McPhie, Svetla

    2014-01-01

    Cryo-electron microscopy (Cryo-EM)(1) is a powerful approach to investigate the functional structure of proteins and complexes in a hydrated state and membrane environment(2). Coagulation Factor VIII (FVIII)(3) is a multi-domain blood plasma glycoprotein. Defect or deficiency of FVIII is the cause for Hemophilia type A - a severe bleeding disorder. Upon proteolytic activation, FVIII binds to the serine protease Factor IXa on the negatively charged platelet membrane, which is critical for normal blood clotting(4). Despite the pivotal role FVIII plays in coagulation, structural information for its membrane-bound state is incomplete(5). Recombinant FVIII concentrate is the most effective drug against Hemophilia type A and commercially available FVIII can be expressed as human or porcine, both forming functional complexes with human Factor IXa(6,7). In this study we present a combination of Cryo-electron microscopy (Cryo-EM), lipid nanotechnology and structure analysis applied to resolve the membrane-bound structure of two highly homologous FVIII forms: human and porcine. The methodology developed in our laboratory to helically organize the two functional recombinant FVIII forms on negatively charged lipid nanotubes (LNT) is described. The representative results demonstrate that our approach is sufficiently sensitive to define the differences in the helical organization between the two highly homologous in sequence (86% sequence identity) proteins. Detailed protocols for the helical organization, Cryo-EM and electron tomography (ET) data acquisition are given. The two-dimensional (2D) and three-dimensional (3D) structure analysis applied to obtain the 3D reconstructions of human and porcine FVIII-LNT is discussed. The presented human and porcine FVIII-LNT structures show the potential of the proposed methodology to calculate the functional, membrane-bound organization of blood coagulation Factor VIII at high resolution.

  15. Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

    PubMed Central

    Koyfman, Alexey Y.; Grushin, Kirill; Stoilova-McPhie, Svetla

    2014-01-01

    Cryo-electron microscopy (Cryo-EM)1 is a powerful approach to investigate the functional structure of proteins and complexes in a hydrated state and membrane environment2. Coagulation Factor VIII (FVIII)3 is a multi-domain blood plasma glycoprotein. Defect or deficiency of FVIII is the cause for Hemophilia type A - a severe bleeding disorder. Upon proteolytic activation, FVIII binds to the serine protease Factor IXa on the negatively charged platelet membrane, which is critical for normal blood clotting4. Despite the pivotal role FVIII plays in coagulation, structural information for its membrane-bound state is incomplete5. Recombinant FVIII concentrate is the most effective drug against Hemophilia type A and commercially available FVIII can be expressed as human or porcine, both forming functional complexes with human Factor IXa6,7. In this study we present a combination of Cryo-electron microscopy (Cryo-EM), lipid nanotechnology and structure analysis applied to resolve the membrane-bound structure of two highly homologous FVIII forms: human and porcine. The methodology developed in our laboratory to helically organize the two functional recombinant FVIII forms on negatively charged lipid nanotubes (LNT) is described. The representative results demonstrate that our approach is sufficiently sensitive to define the differences in the helical organization between the two highly homologous in sequence (86% sequence identity) proteins. Detailed protocols for the helical organization, Cryo-EM and electron tomography (ET) data acquisition are given. The two-dimensional (2D) and three-dimensional (3D) structure analysis applied to obtain the 3D reconstructions of human and porcine FVIII-LNT is discussed. The presented human and porcine FVIII-LNT structures show the potential of the proposed methodology to calculate the functional, membrane-bound organization of blood coagulation Factor VIII at high resolution. PMID:24961276

  16. Effect of magnetic bracelets on the coagulation and anticoagulation systems of the blood of patients with hypertension

    NASA Technical Reports Server (NTRS)

    Bublis, V. V.; Zabrodina, L. V.; Platonova, A. T.; Meyerova, Y. A.

    1974-01-01

    The data which have been obtained on the influence of magnetic bracelets on the coagulation and anticoagulation systems of the blood indicate that the wearing of magnetic bracelets results in a decrease in the coagulation activity of the blood and an increase in the activity of the anticoagulation system. These changes must be viewed as favorable for patients with cardiovascular pathology.

  17. Bio-responsive polymer hydrogels homeostatically regulate blood coagulation.

    PubMed

    Maitz, Manfred F; Freudenberg, Uwe; Tsurkan, Mikhail V; Fischer, Marion; Beyrich, Theresa; Werner, Carsten

    2013-01-01

    Bio-responsive polymer architectures can empower medical therapies by engaging molecular feedback-response mechanisms resembling the homeostatic adaptation of living tissues to varying environmental constraints. Here we show that a blood coagulation-responsive hydrogel system can deliver heparin in amounts triggered by the environmental levels of thrombin, the key enzyme of the coagulation cascade, which--in turn--becomes inactivated due to released heparin. The bio-responsive hydrogel quantitatively quenches blood coagulation over several hours in the presence of pro-coagulant stimuli and during repeated incubation with fresh, non-anticoagulated blood. These features enable the introduced material to provide sustainable, autoregulated anticoagulation, addressing a key challenge of many medical therapies. Beyond that, the explored concept may facilitate the development of materials that allow the effective and controlled application of drugs and biomolecules.

  18. Blood coagulation and metabolic profiles in middle-aged male and female ob/ob mice.

    PubMed

    Ohkura, Naoki; Oishi, Katsutaka; Atsumi, Gen-ichi

    2015-07-01

    Obese and diabetic states in humans are associated with an increased incidence of thrombotic diseases caused by various coagulation abnormalities. Genetically obese ob/ob mice produce metabolic abnormalities similar to those associated with type 2 diabetes. However, little is known about their coagulation features or sex differences. The present study aimed to determine the effects of obese and diabetic complications on blood coagulation and vascular diseases by exploring correlations between blood coagulation and metabolic profiles in middle-aged male and female ob/ob mice. Plasma levels of plasminogen activator inhibitor 1 (PAI-1) were significantly increased, whereas those that of platelet factor-4 (PF-4) was slightly, but significantly increased in male and female ob/ob mice compared with lean counterparts. Prothrombin time (PT) was significantly shortened in female ob/ob mice and activated partial thrombin time (APTT) significantly differed between male and female ob/ob mice. Plasma levels of antithrombin (AT) were significantly increased in male and female ob/ob mice. None of the other coagulation and fibrinolytic factors examined significantly differed between ob/ob mice and lean counterparts. On the contrary, factors such as body weight and cholesterol levels significantly differed between ob/ob and lean mice, whereas glucose, fructosamine and insulin levels significantly differed only in one sex of each strain. These results provided fundamental information about blood coagulation and metabolic features for exploring the function of altered blood coagulation states in ob/ob mice.

  19. Nanoparticles and the blood coagulation system. Part II: safety concerns.

    PubMed

    Ilinskaya, Anna N; Dobrovolskaia, Marina A

    2013-06-01

    Nanoparticle interactions with the blood coagulation system can be beneficial or adverse depending on the intended use of a nanomaterial. Nanoparticles can be engineered to be procoagulant or to carry coagulation-initiating factors to treat certain disorders. Likewise, they can be designed to be anticoagulant or to carry anticoagulant drugs to intervene in other pathological conditions in which coagulation is a concern. An overview of the coagulation system was given and a discussion of a desirable interface between this system and engineered nanomaterials was assessed in part I, which was published in the May 2013 issue of Nanomedicine. Unwanted pro- and anti-coagulant properties of nanoparticles represent significant concerns in the field of nanomedicine, and often hamper the development and transition into the clinic of many promising engineered nanocarriers. This part will focus on the undesirable effects of engineered nanomaterials on the blood coagulation system. We will discuss the relationship between the physicochemical properties of nanoparticles (e.g., size, charge and hydrophobicity) that determine their negative effects on the blood coagulation system in order to understand how manipulation of these properties can help to overcome unwanted side effects.

  20. [Effect of soluble fibrin on the blood coagulation process and platelets aggregation].

    PubMed

    Zaichko, N V; Chernyshenko, T M; Platonova, T M; Volkov, H L

    2006-01-01

    The accumulation of soluble fibrin (SF) in the blood plasma causes acceleration of the final stage of blood coagulation. It increases functional activity of a hemostasis system platelet link, that is the precondition of thrombotic complication. Accumulation of SF in the blood plasma is accompanied by proportional reduction of coagulation time in ancistron and thrombin time tests, and also the intensification of platelets aggregation process. A conclusion was drawn that for early diagnostics of the DIC-syndrom it is expedient to carry out complex estimation of the hemostasis system with obligatory definition of the blood SF content, performance of ancistron and thrombin time tests, and also study of platelets aggregation.

  1. Influence of Blood Collection Systems on Coagulation Tests

    PubMed Central

    Yavaş, Soner; Ayaz, Selime; Köse, S.Kenan; Ulus, Fatma; Ulus, A.Tulga

    2012-01-01

    Objective: Coagulation tests are influenced by pre-analytic conditions such as blood collection systems. Change of glass collection tubes with plastic ones will cause alteration of the test results. The aim of this study was to compare three plastic blood collection tubes with a standard glass blood collection tube and each plastic collection tube with the other two for possible additional tube-to- tube differences. Material and Methods: A total of 284 blood samples were obtained from 42 patients receiving warfarin during their routine controls, besides 29 healthy volunteers. Subgroup analyses were done according to health status. Results: Our study demonstrated that different blood collection tubes have a statistically significant influence on coagulation tests. The magnitude of the effect depends on the tube used. However most of the tests performed on samples obtained from any tube correlated significantly with results obtained from other tube samples. Conclusion: Although blood collection tubes with different brands or properties will have distinct effects on coagulation tests, the influence of these blood collection tubes may be relatively small to interfere with decision-making on dose prescription, therefore lack clinical importance. Correlations between the results showed that, one of these plastic blood collection tubes tested in our study, can be used interchangably for a wide variety of coagulation assays. Conflict of interest:None declared. PMID:24385724

  2. Functional role of residue 193 (chymotrypsin numbering) in serine proteases: influence of side chain length and beta-branching on the catalytic activity of blood coagulation factor XIa.

    PubMed

    Schmidt, Amy E; Sun, Mao-fu; Ogawa, Taketoshi; Bajaj, S Paul; Gailani, David

    2008-02-01

    In serine proteases, Gly193 (chymotrypsin numbering) is conserved with rare exception. Mutants of blood coagulation proteases have been reported with Glu, Ala, Arg or Val substitutions for Gly193. To further understand the role of Gly193 in protease activity, we replaced it with Ala or Val in coagulation factor XIa (FXIa). For comparison to the reported FXIa Glu193 mutant, we prepared FXIa with Asp (short side chain) or Lys (opposite charge) substitutions. Binding of p-aminobenzamidine (pAB) and diisopropylfluorphosphate (DFP) were impaired 1.6-36-fold and 35-478-fold, respectively, indicating distortion of, or altered accessibility to, the S1 and oxyanion-binding sites. Val or Asp substitutions caused the most impairment. Salt bridge formation between the amino terminus of the mature protease moiety at Ile16 and Asp194, essential for catalysis, was impaired 1.4-4-fold. Mutations reduced catalytic efficiency of tripeptide substrate hydrolysis 6-280-fold, with Val or Asp causing the most impairment. Further studies were directed toward macromolecular interactions with the FXIa mutants. kcat for factor IX activation was reduced 8-fold for Ala and 400-1100-fold for other mutants, while binding of the inhibitors antithrombin and amyloid beta-precursor protein Kunitz domain (APPI) was impaired 13-2300-fold and 22-27000-fold, respectively. The data indicate that beta-branching of the side chain of residue 193 is deleterious for interactions with pAB, DFP and amidolytic substrates, situations where no S2'-P2' interactions are involved. When an S2'-P2' interaction is involved (factor IX, antithrombin, APPI), beta-branching and increased side chain length are detrimental. Molecular models indicate that the mutants have impaired S2' binding sites and that beta-branching causes steric conflicts with the FXIa 140-loop, which could perturb the local tertiary structure of the protease domain. In conclusion, enzyme activity is impaired in FXIa when Gly193 is replaced by a non

  3. Plasmin-induced procoagulant effects in the blood coagulation: a crucial role of coagulation factors V and VIII.

    PubMed

    Ogiwara, Kenichi; Nogami, Keiji; Nishiya, Katsumi; Shima, Midori

    2010-09-01

    Plasminogen activators provide effective treatment for patients with acute myocardial infarction. However, paradoxical elevation of thrombin activity associated with failure of clot lysis and recurrent thrombosis has been reported. Generation of thrombin in these circumstances appears to be owing to plasmin (Plm)-induced activation of factor (F) XII. Plm catalyzes proteolysis of several coagulant factors, but the roles of these factors on Plm-mediated procoagulant activity remain to be determined. Recently developed global coagulation assays were used in this investigation. Rotational thromboelastometry using whole blood, clot waveform analysis and thrombin generation tests using plasma, showed that Plm (> or =125 nmol/l) shortened the clotting times in similar dose-dependent manners. In particular, the thrombin generation test, which was unaffected by products of fibrinolysis, revealed the enhanced coagulation with an approximately two-fold increase of peak level of thrombin generation. Studies using alpha2-antiplasmin-deficient plasma revealed that much lower dose of Plm (> or =16 nmol/l) actually contributed to enhancing thrombin generation. The shortening of clotting time could be observed even in the presence of corn trypsin inhibitor, supporting that Plm exerted the procoagulant activity independently of FXII. In addition, using specific coagulation-deficient plasmas, the clot waveform analysis showed that Plm did not shorten the clotting time in only FV-deficient or FVIII-deficient plasma in prothrombin time-based or activated partial thromboplastin time-based assay, respectively. Our results indicated that Plm did possess procoagulant activity in the blood coagulation, and this effect was likely attributed by multicoagulation factors, dependent on FV and/or FVIII.

  4. Aptamer-based modulation of blood coagulation.

    PubMed

    Mayer, G; Rohrbach, F; Pötzsch, B; Müller, J

    2011-11-01

    Nucleic acid based aptamers are single-stranded oligonucleotide ligands isolated from random libraries by an in-vitro selection procedure. Through the formation of unique three-dimensional structures, aptamers are able to selectively interact with a variety of target molecules and are therefore also promising candidates for the development of anticoagulant drugs. While thrombin represents the most prominent enzymatic target in this field, also aptamers directed against other coagulation proteins and proteases have been identified with some currently being tested in clinical trials. In this review, we summarize recent developments in the design and evaluation of aptamers for anticoagulant therapy and research.

  5. Change in fibrinolytic activity under the influence of a constant magnetic field. [blood coagulation normilization in heart patients

    NASA Technical Reports Server (NTRS)

    Yepishina, S. G.

    1974-01-01

    The fibrinolytic activity of plasma changes under the influence of a constant magnetic field (CMF) with a strength of 250 or 2500 oersteds. CMF shows a tendency toward normalization of fibrinolytic processes in the presence of pathological disturbances in fibrinolysis activation.

  6. [Thermoconductimetric method of studying the blood coagulation process].

    PubMed

    Vil'ner, G A; Aleksandrov, G V; Avakova, T A; Neplokh, E G

    1980-01-01

    A method is offered to compensate the effect of the sample temperature variation on the performance of the thermoconductometric unit intended for studying the blood coagulation with an additional thermister. In the course of analysis of the unit measuring circuit some formulas were derived for engineering calculations. This compensation method was shown as efficient one on mathematical models.

  7. Blood coagulation using High Intensity Focused Ultrasound (HIFU)

    NASA Astrophysics Data System (ADS)

    Nguyen, Phuc V.; Oh, Junghwan; Kang, Hyun Wook

    2014-03-01

    High Intensity Focused Ultrasound (HIFU) technology provides a feasible method of achieving thermal coagulation during surgical procedures. One of the potential clinical benefits of HIFU can induce immediate hemostasis without suturing. The objective of this study was to investigate the efficiency of a HIFU system for blood coagulation on severe vascular injury. ngHIFU treatment was implemented immediately after bleeding in artery. The ultrasound probe was made of piezoelectric material, generating a central frequency of 2.0 MHz as well as an ellipsoidal focal spot of 2 mm in lateral dimension and 10 mm in axial dimension. Acoustic coagulation was employed on a perfused chicken artery model in vitro. A surgical incision (1 to 2 mm long) was made with a scapel on the arterial wall, and heparinized autologous blood was made to leak out from the incision with a syringe pump. A total of 5 femoral artery incisions was treated with the HIFU beam. The intensity of 4500 W/cm2 at the focus was applied for all treatments. Complete hemostasis was achieved in all treatments, along with the treatment times of 25 to 50 seconds. The estimated intraoperative blood loss was from 2 to 5 mL. The proposed HIFU system may provide an effective method for immediate blood coagulation for arteries and veins in clinical applications.

  8. Evaluation of whole blood coagulation process by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Xu, Xiangqun; Lin, Jia

    2010-11-01

    This study was to investigate the feasibility of using optical coherence tomography (OCT) to evaluate whole blood coagulation process. Attenuation coefficients and 1/e light penetration depth (D1/e) against time of human whole blood during in vitro clot formation under static were measured from the OCT profiles of reflectance vs depth. The results obtained clearly showed that the optical parameters are able to identify three stages during the in vitro blood clotting process. It is concluded that D1/e measured by OCT is a potential parameter to quantify and follow the liquid-gel transition of blood during clotting.

  9. Shortened blood coagulation times in genetically obese rats and diet-induced obese mice.

    PubMed

    Kaji, Noriyuki; Nagakubo, Dai; Hashida, Shin-Ichi; Takahashi, Saya; Kuratani, Motoi; Hirai, Norihiko; Shirai, Mitsuyuki; Asai, Fumitoshi

    2013-01-01

    The aim of this study was to investigate blood coagulation times in genetically obese rats and diet-induced obese (DIO) mice in order to clarify the relationship between visceral obesity and blood coagulation. WBN/Kob-Lepr(fa) (fa/fa) rats, a genetically obese model, exhibited a significantly shorter activated partial thromboplastin time (aPTT) and prothrombin time (PT) than age-matched Wistar rats. C57BL/6J mice fed a high-fat diet (60%), a DIO model, exhibited significantly shorter aPTT, PT and thrombin time than lean mice fed a standard diet. Higher body weight, visceral fat weight and insulin resistance were also shared by fa/fa rats and DIO mice. These results suggest that visceral obesity is related to accelerated blood coagulation in addition to disrupted metabolism of glucose and lipids.

  10. Activated platelet–T-cell conjugates in peripheral blood of patients with HIV infection: coupling coagulation/inflammation and T cells

    PubMed Central

    Green, Samantha A.; Smith, Mindy; Hasley, Rebecca B.; Stephany, David; Harned, Adam; Nagashima, Kunio; Abdullah, Shahed; Pittaluga, Stefania; Imamichi, Tomozumi; Qin, Jing; Rupert, Adam; Ober, Alex; Lane, H. Clifford; Catalfamo, Marta

    2015-01-01

    Background: Despite successfully suppressed viremia by treatment, patients with high levels of biomarkers of coagulation/inflammation are at an increased risk of developing non-AIDS defining serious illnesses such as cardiovascular diseases. Thus, there is a relationship between persistent immune activation and coagulation/inflammation, although the mechanisms are poorly understood. Platelets play an important role in this process. Although interactions between platelets and elements of the innate immune system, such as monocytes, are well described, little is known about the interaction between platelets and the adaptive immune system. Design: We investigated the interaction of a component of the coagulation system, platelets, and the adaptive immune system T cells. Methods: Healthy controls and combination antiretroviral therapy (cART)-treated HIV-infected patients with viral loads of less than 40 copies/ml for more than 15 months were analysed for platelet–T-cell conjugate formation. Results: Platelets can form conjugates with T cells and were preferentially seen in CD4+ and CD8+ T-cell subsets with more differentiated phenotypes [memory, memory/effector and terminal effector memory (TEM)]. Compared with healthy controls, these conjugates in patients with HIV infection were more frequent, more often composed of activated platelets (CD42b+CD62P+), and were significantly associated with the D-dimer serum levels. Conclusion: These data support a model in which platelet–T-cell conjugates may play a critical role in the fast recruitment of antigen-experienced T cells to the place of injury. This mechanism can contribute in maintaining a state of coagulation/inflammation observed in these patients contributing to the pathology of the disease. PMID:26002800

  11. Multifrequency acoustics as a probe of mesoscopic blood coagulation dynamics

    NASA Astrophysics Data System (ADS)

    Ganesan, Adarsh; Rajendran, Gokulnath; Ercole, Ari; Seshia, Ashwin

    2016-08-01

    Coagulation is a complex enzymatic polymerisation cascade. Disordered coagulation is common in medicine and may be life-threatening yet clinical assays are typically bulky and/or provide an incomplete picture of clot mechanical evolution. We present the adaptation of an in-plane acoustic wave device: quartz crystal microbalance with dissipation at multiple harmonics to determine the time-evolution of mesoscale mechanical properties of clot formation in vitro. This approach is sensitive to changes in surface and bulk clot structure in various models of induced coagulopathy. Furthermore, we are able to show that clot formation at surfaces has different kinetics and mechanical strength to that in the bulk, which may have implications for the design of bioprosthetic materials. The "Multifrequency acoustics" approach thus enables unique capability to portray biological processes concerning blood coagulation.

  12. Adaptive Force Sonorheometry for Assessment of Whole Blood Coagulation

    PubMed Central

    Mauldin, F. William; Viola, Francesco; Hamer, Theresa C.; Ahmed, Eman M.; Crawford, Shawna B.; Haverstick, Doris M.; Lawrence, Michael B.; Walker, William F.

    2010-01-01

    Background: Viscoelastic diagnostics that monitor the hemostatic function of whole blood (WB), such as thromboelastography, have been developed with demonstrated clinical utility. By measuring the cumulative effects of all components of hemostasis, viscoelastic diagnostics have circumvented many of the challenges associated with more common tests of blood coagulation. Methods: We describe a new technology, called sonorheometry, that adaptively applies acoustic radiation force to assess coagulation function in WB. The repeatability (precision) of coagulation parameters was assessed using citrated WB samples. A reference range of coagulation parameters, along with corresponding measurements from prothrombin time (PT) and partial thromboplastin time (PTT), were obtained from WB samples of 20 healthy volunteers. In another study, sonorheometry monitored anticoagulation with heparin (0 – 5 IU/ml) and reversal from varied dosages of protamine (0 – 10 IU/ml) in heparinized WB (2 IU/ml). Results: Sonorheometry exhibited low CVs for parameters: clot initiation time (TC1), < 7%; clot stabilization time (TC2), < 6.5%; and clotting angle (θ), < 3.5%. Good correlation was observed between clotting times, TC1 and TC2, and PTT (r = 0.65 and 0.74 respectively; n=18). Linearity to heparin dosage was observed with average linearity r > 0.98 for all coagulation parameters. We observed maximum reversal of heparin anticoagulation at protamine to heparin ratios of 1.4:1 from TC1 (P=0.6) and 1.2:1 from θ (P=0.55). Conclusions: Sonorheometry is a non-contact method for precise assessment of WB coagulation. PMID:20096680

  13. Proteins, platelets, and blood coagulation at biomaterial interfaces.

    PubMed

    Xu, Li-Chong; Bauer, James W; Siedlecki, Christopher A

    2014-12-01

    Blood coagulation and platelet adhesion remain major impediments to the use of biomaterials in implantable medical devices. There is still significant controversy and question in the field regarding the role that surfaces play in this process. This manuscript addresses this topic area and reports on state of the art in the field. Particular emphasis is placed on the subject of surface engineering and surface measurements that allow for control and observation of surface-mediated biological responses in blood and test solutions. Appropriate use of surface texturing and chemical patterning methodologies allow for reduction of both blood coagulation and platelet adhesion, and new methods of surface interrogation at high resolution allow for measurement of the relevant biological factors.

  14. Proteins, platelets, and blood coagulation at biomaterial interfaces.

    PubMed

    Xu, Li-Chong; Bauer, James W; Siedlecki, Christopher A

    2014-12-01

    Blood coagulation and platelet adhesion remain major impediments to the use of biomaterials in implantable medical devices. There is still significant controversy and question in the field regarding the role that surfaces play in this process. This manuscript addresses this topic area and reports on state of the art in the field. Particular emphasis is placed on the subject of surface engineering and surface measurements that allow for control and observation of surface-mediated biological responses in blood and test solutions. Appropriate use of surface texturing and chemical patterning methodologies allow for reduction of both blood coagulation and platelet adhesion, and new methods of surface interrogation at high resolution allow for measurement of the relevant biological factors. PMID:25448722

  15. Proteins, Platelets, and Blood Coagulation at Biomaterial Interfaces

    PubMed Central

    Xu, Li-Chong; Bauer, James; Siedlecki, Christopher A.

    2015-01-01

    Blood coagulation and platelet adhesion remain major impediments to the use of biomaterials in implantable medical devices. There is still significant controversy and question in the field regarding the role that surfaces play in this process. This manuscript addresses this topic area and reports on state of the art in the field. Particular emphasis is placed on the subject of surface engineering and surface measurements that allow for control and observation of surface-mediated biological responses in blood and test solutions. Appropriate use of surface texturing and chemical patterning methodologies allow for reduction of both blood coagulation and platelet adhesion, and new methods of surface interrogation at high resolution allow for measurement of the relevant biological factors. PMID:25448722

  16. Mesoscopic Modeling of Blood Clotting: Coagulation Cascade and Platelets Adhesion

    NASA Astrophysics Data System (ADS)

    Yazdani, Alireza; Li, Zhen; Karniadakis, George

    2015-11-01

    The process of clot formation and growth at a site on a blood vessel wall involve a number of multi-scale simultaneous processes including: multiple chemical reactions in the coagulation cascade, species transport and flow. To model these processes we have incorporated advection-diffusion-reaction (ADR) of multiple species into an extended version of Dissipative Particle Dynamics (DPD) method which is considered as a coarse-grained Molecular Dynamics method. At the continuum level this is equivalent to the Navier-Stokes equation plus one advection-diffusion equation for each specie. The chemistry of clot formation is now understood to be determined by mechanisms involving reactions among many species in dilute solution, where reaction rate constants and species diffusion coefficients in plasma are known. The role of blood particulates, i.e. red cells and platelets, in the clotting process is studied by including them separately and together in the simulations. An agonist-induced platelet activation mechanism is presented, while platelets adhesive dynamics based on a stochastic bond formation/dissociation process is included in the model.

  17. Coagulation, Protease Activated Receptors and Viral Myocarditis

    PubMed Central

    Antoniak, Silvio; Mackman, Nigel

    2013-01-01

    The coagulation protease cascade plays an essential role in hemostasis. In addition, a clot contributes to host defense by limiting the spread of pathogens. Coagulation proteases induce intracellular signaling by cleavage of cell surface receptors called protease-activated receptors (PARs). These receptors allow cells to sense changes in the extracellular environment, such as infection. Viruses activate the coagulation cascade by inducing tissue factor expression and by disrupting the endothelium. Virus infection of the heart can cause myocarditis, cardiac remodeling and heart failure. Recent studies using a mouse model have shown that tissue factor, thrombin and PAR-1 signaling all positively regulate the innate immune during viral myocarditis. In contrast, PAR-2 signaling was found to inhibit interferon-β expression and the innate immune response. These observations suggest that anticoagulants may impair the innate immune response to viral infection and that inhibition of PAR-2 may be a new target to reduce viral myocarditis.. PMID:24203054

  18. Do different substitution patterns or plant origin in hydroxyethyl starches affect blood coagulation in vitro?

    PubMed

    Matsota, Paraskevi; Politou, Marianna; Kalimeris, Konstantinos; Apostolaki, Stella; Merkouri, Efrosyni; Gialeraki, Argyri; Travlou, Anthi; Kostopanagiotou, Georgia

    2010-07-01

    The effect of hydroxyethyl starches (HES) on blood coagulation is affected by their molecular weight, their molar substitution and the C2/C6 ratio. The solutions of 6% HES 130/0.4 and 6% HES 130/0.42 have similar molecular weight and molar substitution but different C2/C6 ratio and plant origin. In the present study, the comparative effect of 6% HES 130/0.4 versus 6% HES 130/0.42 on blood coagulation was investigated in vitro. Thirty milliliter of blood was obtained from 10 healthy volunteers and was diluted by 10, 30 and 50% using either 6% HES 130/0.4 or HES 130/0.42, respectively. Blood coagulation was assessed using thrombelastography measurements (clotting time, clot formation time, maximal clot firmness and alpha-angle). The assessment of platelet function was performed with whole blood aggregometry after adding thrombin-receptor-activating protein. No differences were noted between respective dilutions of the two HES. Both colloids produced significant reductions below the reference values range in clotting time at 10, 30 and 50% dilutions. The 50% dilution of both colloids resulted in significant reduction of maximal clot firmness, alpha-angle and platelet aggregation. The present study showed that the corn-derived 6% HES 130/0.4 and the potato-derived 6% HES 130/0.42 have the same effect on blood coagulation in vitro.

  19. Dynamic and quantitative assessment of blood coagulation using optical coherence elastography

    NASA Astrophysics Data System (ADS)

    Xu, Xiangqun; Zhu, Jiang; Chen, Zhongping

    2016-04-01

    Reliable clot diagnostic systems are needed for directing treatment in a broad spectrum of cardiovascular diseases and coagulopathy. Here, we report on non-contact measurement of elastic modulus for dynamic and quantitative assessment of whole blood coagulation using acoustic radiation force orthogonal excitation optical coherence elastography (ARFOE-OCE). In this system, acoustic radiation force (ARF) is produced by a remote ultrasonic transducer, and a shear wave induced by ARF excitation is detected by the optical coherence tomography (OCT) system. During porcine whole blood coagulation, changes in the elastic property of the clots increase the shear modulus of the sample, altering the propagating velocity of the shear wave. Consequently, dynamic blood coagulation status can be measured quantitatively by relating the velocity of the shear wave with clinically relevant coagulation metrics, including reaction time, clot formation kinetics and maximum shear modulus. The results show that the ARFOE-OCE is sensitive to the clot formation kinetics and can differentiate the elastic properties of the recalcified porcine whole blood, blood added with kaolin as an activator, and blood spiked with fibrinogen.

  20. [Abnormality of blood coagulation indexes in patients with de novo acute leukemia and its clinical significance].

    PubMed

    Xiao, Fang-Fang; Hu, Kai-Xun; Guo, Mei; Qiao, Jian-Hui; Sun, Qi-Yun; Ai, Hui-Sheng; Yu, Chang-Lin

    2013-04-01

    To explore hemorrhage risk and the clinical significance of abnormal change of prothrombin time (PT), activated partial thromboplastin time (APTT), plasma fibrinogen (FIB), plasma thrombin time (TT) and d-dimer (D-D) in de novo acute leukemia (except for APL), the different bleeding manifestations of 114 cases of de novo acute leukemia with different coagulation indexes were analyzed retrospectively. The correlation between these blood coagulation indexes and the possible correlative clinical characteristics were analysed, including age, sex, type of acute leukemia, initial white blood cell(WBC) and platelet(Plt) count, the proportion of blast cells in bone marrow and cytogenetic abnormality of patients at diagnosis. The results indicated that the incidence of abnormal blood coagulation was as high as 78.1% for de novo AL patients. These patients with 5 normal blood coagulation indexes may have mild bleeding manifestation, but the more abnormal indexes, the more severe bleeding. Both PT and D-D were sensitive indexes for diagnosis of level II bleeding. Incidence of abnormal blood coagulation significantly correlates with the proportion of blast cells in bone marrow (χ(2) = 4.184, OR = 1.021, P < 0.05) and more with D-D (P < 0.01), while age, sex, type of AL, WBC count, Plt count and abnormality of cytogenetics did not correlate with abnormal blood coagulation. It is concluded that the coagulation and fibrinolysis are abnormal in most patients with de novo acute leukemia. More abnormal indexes indicate more severe bleeding, and both PT and D-D are sensitive indexes for diagnosis of level II bleeding. Higher proportion of blast cells in bone marrow predicts higher incidence of abnormal blood clotting. Acute leukemia with elderly age, high white blood cell count and adverse cytogenetics do not predict severer abnormal blood clotting. Detection of PT, APTT, TT, FIB, and D-D may help to judge whether the patients are in a state of hypercoagulability or disseminated

  1. Numerical simulations of a reduced model for blood coagulation

    NASA Astrophysics Data System (ADS)

    Pavlova, Jevgenija; Fasano, Antonio; Sequeira, Adélia

    2016-04-01

    In this work, the three-dimensional numerical resolution of a complex mathematical model for the blood coagulation process is presented. The model was illustrated in Fasano et al. (Clin Hemorheol Microcirc 51:1-14, 2012), Pavlova et al. (Theor Biol 380:367-379, 2015). It incorporates the action of the biochemical and cellular components of blood as well as the effects of the flow. The model is characterized by a reduction in the biochemical network and considers the impact of the blood slip at the vessel wall. Numerical results showing the capacity of the model to predict different perturbations in the hemostatic system are discussed.

  2. Influence of a constant magnetic field on thrombocytes. [delay of blood coagulation time

    NASA Technical Reports Server (NTRS)

    Meyerova, Y. A.

    1974-01-01

    In an experiment on white mice it was found that a constant electromagnetic field with strength of 250-275 oersteds is biologically active at an exposure of 55 minutes. Qualitative and morphological changes in thrombocytes 1-3 days following exposure reduced their numbers, prolonged blood coagulation time and increased the number of leucocytes.

  3. Inhibiting platelet-stimulated blood coagulation by inhibition of mitochondrial respiration.

    PubMed

    Barile, Christopher J; Herrmann, Paul C; Tyvoll, David A; Collman, James P; Decreau, Richard A; Bull, Brian S

    2012-02-14

    Platelets are important mediators of blood coagulation that lack nuclei, but contain mitochondria. Although the presence of mitochondria in platelets has long been recognized, platelet mitochondrial function remains largely unaddressed. On the basis of a small amount of literature that suggests platelet mitochondria are functional, we hypothesized that the inhibition of platelet mitochondria disrupts platelet function and platelet-activated blood coagulation. To test this hypothesis, members of the tetrazole, thiazole, and 1,2,3-triazole families of small molecule heterocycles were screened for the ability to inhibit isolated mitochondrial respiration and coagulation of whole blood. The families of heterocycles screened were chosen on the basis of the ability of the heterocycle family to inhibit a biomimetic model of cytochrome c oxidase (CcO). The strength of mitochondrial inhibition correlates with each compound's ability to deter platelet stimulation and platelet-activated blood clotting. These results suggest that for this class of molecules, inhibition of blood coagulation may be occurring through a mechanism involving mitochondrial inhibition.

  4. Human plasma kallikrein releases neutrophil elastase during blood coagulation.

    PubMed Central

    Wachtfogel, Y T; Kucich, U; James, H L; Scott, C F; Schapira, M; Zimmerman, M; Cohen, A B; Colman, R W

    1983-01-01

    Elastase is released from human neutrophils during the early events of blood coagulation. Human plasma kallikrein has been shown to stimulate neutrophil chemotaxis, aggregation, and oxygen consumption. Therefore, the ability of kallikrein to release neutrophil elastase was investigated. Neutrophils were isolated by dextran sedimentation, and elastase release was measured by both an enzyme-linked immunosorbent assay, and an enzymatic assay using t-butoxy-carbonyl-Ala-Ala-Pro-Val-amino methyl coumarin as the substrate. Kallikrein, 0.1-1.0 U/ml, (0.045-0.45 microM), was incubated with neutrophils that were preincubated with cytochalasin B (5 micrograms/ml). The release of elastase was found to be proportional to the kallikrein concentration. Kallikrein released a maximum of 34% of the total elastase content, as measured by solubilizing the neutrophils in the nonionic detergent Triton X-100. A series of experiments was carried out to determine if kallikrein was a major enzyme involved in neutrophil elastase release during blood coagulation. When 10 million neutrophils were incubated in 1 ml of normal plasma in the presence of 30 mM CaCl2 for 90 min, 2.75 micrograms of elastase was released. In contrast, neutrophils incubated in prekallikrein-deficient or Factor XII-deficient plasma released less than half of the elastase, as compared with normal plasma. The addition of purified prekallikrein to prekallikrein-deficient plasma restored neutrophil elastase release to normal levels. Moreover, release of elastase was enhanced in plasma deficient in C1-inhibitor, the major plasma inhibitor of kallikrein. This release was not dependent upon further steps in the coagulation pathway, or on C5a, since levels of elastase, released in Factor XI- or C5-deficient plasma, were similar to that in normal plasma, and an antibody to C5 failed to inhibit elastase release. These data suggest that kallikrein may be a major enzyme responsible for the release of elastase during blood

  5. Simultaneous measurement of red blood cell aggregation and whole blood coagulation using high-frequency ultrasound.

    PubMed

    Nam, Kweon-Ho; Yeom, Eunseop; Ha, Hojin; Lee, Sang Joon

    2012-03-01

    This study aims to investigate the feasibility of using high-frequency ultrasound (HFUS) for simultaneous monitoring of blood coagulation and red blood cell (RBC) aggregation. Using a 35-MHz ultrasound scanner, ultrasound speckle data were acquired from whole blood samples of three experimental groups of rats, including 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS)-treated, noncoagulation and normal control groups. The variations of blood echogenicity, the shape parameters of probability distribution of speckle intensity (skewness and kurtosis) and the correlation coefficient between two consecutive speckle data were calculated as a function of time starting from immediately after taking blood. The blood echogenicity increases rapidly to plateaus at the early stage of measurement for all the experimental groups caused by the formation of RBC aggregates. The DIDS-treated group exhibits the lowest echogenicity level due to the inhibitory effect of DIDS on RBC aggregation. The correlation analysis between consecutive speckle patterns seems to be useful to examine the variation of blood fluidity and the progress of clot formation. Whole blood coagulation is observed to be accelerated by DIDS treatment. In addition, the results of skewness and kurtosis analysis indicated that RBC aggregates may be disrupted during blood coagulation. The present study suggests that HFUS has good potential for simultaneous monitoring of RBC aggregation and blood coagulation to examine the relationship between them.

  6. The vulnerable blood. Coagulation and clot structure in diabetes mellitus.

    PubMed

    Hess, K

    2015-01-01

    Patients with diabetes are at increased risk of cardiovascular morbidity and mortality. While arteriosclerotic lesions have long been recognized as the underlying cause more recent studies suggest that alterations of the blood are also critically involved. Following plaque rupture, adherence of platelets is followed by the formation of a cross-linked fibrin clot. Patients with diabetes exhibit a prothrombotic milieu consisting of hyper reactive platelets, a tight and rigid clot structure which is due to up-regulation of coagulation factors and prolongation of clot lysis. Metabolic alterations as well as inflammatory processes, which are up-regulated in diabetes, are thought to be the main underlying causes. More recently, the complement cascade has emerged as a potential new player in this context with several complement components directly influencing both platelet function and coagulation. This review provides an overview concerning the changes that lead to alterations of platelet function and clot structure in diabetes.

  7. Coagulant and anticoagulant activities in Jatropha curcas latex.

    PubMed

    Osoniyi, Omolaja; Onajobi, Funmi

    2003-11-01

    Jatropha curcas Linn. (Euphorbiaceae), a medicinal plant commonly grown in the Tropics, is traditionally used as a haemostatic. Investigation of the coagulant activity of the latex of Jatropha curcas showed that whole latex significantly (P<0.01) reduced the clotting time of human blood. Diluted latex, however, prolonged the clotting time: at high dilutions, the blood did not clot at all. This indicates that Jatropha curcas latex possesses both procoagulant and anticoagulant activities. Prothrombin time (PT) and activated partial thromboplastin time (APTT) tests on plasma confirm these observations. Solvent partitioning of the latex with ethyl acetate and butanol led to a partial separation of the two opposing activities: at low concentrations, the ethyl acetate fraction exhibited a procoagulant activity, while the butanol fraction had the highest anticoagulant activity. The residual aqueous fraction had no significant effect on the clotting time of blood and the PT but slightly prolonged the APTT.

  8. Biological and analytical variations of 16 parameters related to coagulation screening tests and the activity of coagulation factors.

    PubMed

    Chen, Qian; Shou, Weiling; Wu, Wei; Guo, Ye; Zhang, Yujuan; Huang, Chunmei; Cui, Wei

    2015-04-01

    To accurately estimate longitudinal changes in individuals, it is important to take into consideration the biological variability of the measurement. The few studies available on the biological variations of coagulation parameters are mostly outdated. We confirmed the published results using modern, fully automated methods. Furthermore, we added data for additional coagulation parameters. At 8:00 am, 12:00 pm, and 4:00 pm on days 1, 3, and 5, venous blood was collected from 31 healthy volunteers. A total of 16 parameters related to coagulation screening tests as well as the activity of coagulation factors were analyzed; these included prothrombin time, fibrinogen (Fbg), activated partial thromboplastin time, thrombin time, international normalized ratio, prothrombin time activity, activated partial thromboplastin time ratio, fibrin(-ogen) degradation products, as well as the activity of factor II, factor V, factor VII, factor VIII, factor IX, and factor X. All intraindividual coefficients of variation (CVI) values for the parameters of the screening tests (except Fbg) were less than 5%. Conversely, the CVI values for the activity of coagulation factors were all greater than 5%. In addition, we calculated the reference change value to determine whether a significant difference exists between two test results from the same individual.

  9. Coagulation changes during lower body negative pressure and blood loss in humans.

    PubMed

    van Helmond, Noud; Johnson, Blair D; Curry, Timothy B; Cap, Andrew P; Convertino, Victor A; Joyner, Michael J

    2015-11-01

    We tested the hypothesis that markers of coagulation activation are greater during lower body negative pressure (LBNP) than those obtained during blood loss (BL). We assessed coagulation using both standard clinical tests and thrombelastography (TEG) in 12 men who performed a LBNP and BL protocol in a randomized order. LBNP consisted of 5-min stages at 0, -15, -30, and -45 mmHg of suction. BL included 5 min at baseline and following three stages of 333 ml of blood removal (up to 1,000 ml total). Arterial blood draws were performed at baseline and after the last stage of each protocol. We found that LBNP to -45 mmHg is a greater central hypovolemic stimulus versus BL; therefore, the coagulation markers were plotted against central venous pressure (CVP) to obtain stimulus-response relationships using the linear regression line slopes for both protocols. Paired t-tests were used to determine whether the slopes of these regression lines fell on similar trajectories for each protocol. Mean regression line slopes for coagulation markers versus CVP fell on similar trajectories during both protocols, except for TEG α° angle (-0.42 ± 0.96 during LBNP vs. -2.41 ± 1.13°/mmHg during BL; P < 0.05). During both LBNP and BL, coagulation was accelerated as evidenced by shortened R-times (LBNP, 9.9 ± 2.4 to 6.2 ± 1.1; BL, 8.7 ± 1.3 to 6.4 ± 0.4 min; both P < 0.05). Our results indicate that LBNP models the general changes in coagulation markers observed during BL.

  10. Hereditary blood coagulation disorders: management and dental treatment.

    PubMed

    Gómez-Moreno, G; Cutando-Soriano, A; Arana, C; Scully, C

    2005-11-01

    Patients with hereditary hemostatic disorders, characterized by a tendency to bleeding or thrombosis, constitute a serious challenge in the dental practice. Advances in the medical diagnosis of hemostatic disorders have exposed dental professionals to new patients not amenable to the application of the management protocols associated with other, more well-known, disorders. It is the aim of this paper to review the evidence, to highlight the areas of major concern, and to suggest management regimens for patients with hereditary hemostatic disorders. An extensive review has been made (PubMed, Science Direct, Web of Knowledge, etc.) of literature pertaining to hereditary disorders affecting blood coagulation factors and how they affect the practice of dentistry. Several aspects relating to the care of such patients must be recognized and taken into consideration when dental treatment is planned. Replacement of deficient coagulation factors ensures that safe dental treatment will be carried out. However, the half-life of such coagulation factors requires that dental treatment be specifically planned and adapted to the type of pathology involved.

  11. Synthetic oligopeptide substrates: their diagnostic application in blood coagulation, fibrinolysis, and other pathologic states

    SciTech Connect

    Huseby, R.M.; Smith, R.E.

    1980-01-01

    This review article with 522 references, focuses on the use of synthetic oligopepide substrates to measure the activity of proteoytic enzymes in human physiology and pathology. A classification of proteinases based on their mechanism of action is presented. The application of these synthetic oligopeptide substrates to understand the disorders of the blood coagulation and fibrinolytic system is reviewed. Intracellular functioning proteinases were also assessed in relation to certain pathologies where their abnormal activity is recognized.

  12. Surface-mediated molecular events in material-induced blood-plasma coagulation

    NASA Astrophysics Data System (ADS)

    Chatterjee, Kaushik

    Coagulation and thrombosis persist as major impediments associated with the use of blood-contacting medical devices. We are investigating the molecular mechanism underlying material-induced blood-plasma coagulation focusing on the role of the surface as a step towards prospective development of improved hemocompatible biomaterials. A classic observation in hematology is that blood/blood-plasma in contact with clean glass surface clots faster than when in contact with many plastic surfaces. The traditional biochemical theory explaining the underlying molecular mechanism suggests that hydrophilic surfaces, like that of glass, are specific activators of the coagulation cascade because of the negatively-charged groups on the surface. Hydrophobic surfaces are poor procoagulants or essentially "benign" because they lack anionic groups. Further, these negatively-charged surfaces are believed to not only activate blood factor XII (FXII), the key protein in contact activation, but also play a cofactor role in the amplification and propagation reactions that ultimately lead to clot formation. In sharp contrast to the traditional theory, our investigations indicate a need for a paradigm shift in the proposed sequence of contact activation events to incorporate the role of protein adsorption at the material surfaces. These studies have lead to the central hypothesis for this work proposing that protein adsorption to hydrophobic surfaces attenuates the contact activation reactions so that poorly-adsorbent hydrophilic surfaces appear to be stronger procoagulants relative to hydrophobic surfaces. Our preliminary studies measuring the plasma coagulation response of activated FXII (FXIIa) on different model surfaces suggested that the material did not play a cofactor role in the processing of this enzyme dose through the coagulation pathway. Therefore, we focused our efforts on studying the mechanism of initial production of enzyme at the procoagulant surface. Calculations for the

  13. Size-dependent effects of nanoparticles on enzymes in the blood coagulation cascade.

    PubMed

    Sanfins, Elodie; Augustsson, Cecilia; Dahlbäck, Björn; Linse, Sara; Cedervall, Tommy

    2014-08-13

    Nanoparticles (NPs) are increasingly used in diagnostic and drug delivery. After entering the bloodstream, a protein corona will form around NPs. The size and curvature of NPs is one of the major characteristics affecting the composition of bound protein in the corona. Key initiators of the intrinsic pathway of blood coagulation, the contact activation complex, (Kallikrein, Factor XII, and high molecular weight Kininogen) have previously been identified on NPs surfaces. We show that the functional impact of carboxyl-modified polystyrene NPs on these initiators of the intrinsic pathway is size dependent. NPs with high curvature affect the enzymatic activity differently from NPs with low curvature. The size dependency is evident in full blood plasma as well as in solutions of single coagulation factors. NPs induce significant alteration of the enzymatic activity in a size-dependent manner, and enzyme kinetics studies show a critical role for NPs surface area and curvature.

  14. Using a Systems Pharmacology Model of the Blood Coagulation Network to Predict the Effects of Various Therapies on Biomarkers

    PubMed Central

    Nayak, S; Lee, D; Patel-Hett, S; Pittman, DD; Martin, SW; Heatherington, AC; Vicini, P; Hua, F

    2015-01-01

    A number of therapeutics have been developed or are under development aiming to modulate the coagulation network to treat various diseases. We used a systems model to better understand the effect of modulating various components on blood coagulation. A computational model of the coagulation network was built to match in-house in vitro thrombin generation and activated Partial Thromboplastin Time (aPTT) data with various concentrations of recombinant factor VIIa (FVIIa) or factor Xa added to normal human plasma or factor VIII-deficient plasma. Sensitivity analysis applied to the model revealed that lag time, peak thrombin concentration, area under the curve (AUC) of the thrombin generation profile, and aPTT show different sensitivity to changes in coagulation factors’ concentrations and type of plasma used (normal or factor VIII-deficient). We also used the model to explore how variability in concentrations of the proteins in coagulation network can impact the response to FVIIa treatment. PMID:26312163

  15. Using a Systems Pharmacology Model of the Blood Coagulation Network to Predict the Effects of Various Therapies on Biomarkers.

    PubMed

    Nayak, S; Lee, D; Patel-Hett, S; Pittman, D D; Martin, S W; Heatherington, A C; Vicini, P; Hua, F

    2015-07-01

    A number of therapeutics have been developed or are under development aiming to modulate the coagulation network to treat various diseases. We used a systems model to better understand the effect of modulating various components on blood coagulation. A computational model of the coagulation network was built to match in-house in vitro thrombin generation and activated Partial Thromboplastin Time (aPTT) data with various concentrations of recombinant factor VIIa (FVIIa) or factor Xa added to normal human plasma or factor VIII-deficient plasma. Sensitivity analysis applied to the model revealed that lag time, peak thrombin concentration, area under the curve (AUC) of the thrombin generation profile, and aPTT show different sensitivity to changes in coagulation factors' concentrations and type of plasma used (normal or factor VIII-deficient). We also used the model to explore how variability in concentrations of the proteins in coagulation network can impact the response to FVIIa treatment.

  16. Coagulation competence and fluid recruitment after moderate blood loss in young men.

    PubMed

    Zaar, Morten; Mørkeberg, Jakob; Pott, Frank C; Johansson, Pär I; Secher, Niels H

    2014-09-01

    The coagulation system is activated by a reduction of the central blood volume during orthostatic stress and lower body negative pressure suggesting that also a blood loss enhances coagulation. During bleeding, however, the central blood volume is supported by fluid recruitment to the circulation and redistribution of the blood volume. In eight supine male volunteers (24 ± 3 years, blood volume of 6.9 ± 0.7 l; mean ± SD), 2 × 450 ml blood was withdrawn over ∼ 30 min while cardiovascular variables were monitored. Coagulation was evaluated by thrombelastography, and fluid recruitment was estimated by red blood cell count. Withdrawing 900 ml blood increased heart rate (62 ± 7 to 69 ± 13 bpm, P < 0.05; mean ± SD) and reduced stroke volume (113 ± 12 to 96 ± 14 ml, P < 0.05) leaving cardiac output, mean arterial pressure, and total peripheral resistance unchanged and, furthermore, reduced red blood cell count (4.80 ± 0.33 to 4.64 ± 0.37 × 10(12) cells l(-1), P < 0.05) indicating that 218 ± 173 ml fluid was recruited to the circulation. Withdrawing 450 ml blood reduced the time until initial fibrin formation (R: 6.5 ± 0.9 to 5.1 ± 1.0 min, P < 0.01), whereas the rate of clot formation increased after withdrawal of 900 ml blood (α-Angle: 66 ± 4 to 70 ± 3 deg, P < 0.01). Clot strength (maximal amplitude: 57 ± 4 mm), clot lysis 30 min after maximal amplitude (LY30: 0.8% [0-3.5%] (median [range])), and platelet count (218 ± 25 × 10(9) l(-1)) were unaffected. For supine males, ∼ 25% of a moderate blood loss is compensated by fluid recruitment to the circulation, which may explain the minor cardiovascular response. Yet, a blood loss of 450 ml accelerates coagulation, and this is further accentuated when blood loss is 900 ml.

  17. Coagulation competence and fluid recruitment after moderate blood loss in young men.

    PubMed

    Zaar, Morten; Mørkeberg, Jakob; Pott, Frank C; Johansson, Pär I; Secher, Niels H

    2014-09-01

    The coagulation system is activated by a reduction of the central blood volume during orthostatic stress and lower body negative pressure suggesting that also a blood loss enhances coagulation. During bleeding, however, the central blood volume is supported by fluid recruitment to the circulation and redistribution of the blood volume. In eight supine male volunteers (24 ± 3 years, blood volume of 6.9 ± 0.7 l; mean ± SD), 2 × 450 ml blood was withdrawn over ∼ 30 min while cardiovascular variables were monitored. Coagulation was evaluated by thrombelastography, and fluid recruitment was estimated by red blood cell count. Withdrawing 900 ml blood increased heart rate (62 ± 7 to 69 ± 13 bpm, P < 0.05; mean ± SD) and reduced stroke volume (113 ± 12 to 96 ± 14 ml, P < 0.05) leaving cardiac output, mean arterial pressure, and total peripheral resistance unchanged and, furthermore, reduced red blood cell count (4.80 ± 0.33 to 4.64 ± 0.37 × 10(12) cells l(-1), P < 0.05) indicating that 218 ± 173 ml fluid was recruited to the circulation. Withdrawing 450 ml blood reduced the time until initial fibrin formation (R: 6.5 ± 0.9 to 5.1 ± 1.0 min, P < 0.01), whereas the rate of clot formation increased after withdrawal of 900 ml blood (α-Angle: 66 ± 4 to 70 ± 3 deg, P < 0.01). Clot strength (maximal amplitude: 57 ± 4 mm), clot lysis 30 min after maximal amplitude (LY30: 0.8% [0-3.5%] (median [range])), and platelet count (218 ± 25 × 10(9) l(-1)) were unaffected. For supine males, ∼ 25% of a moderate blood loss is compensated by fluid recruitment to the circulation, which may explain the minor cardiovascular response. Yet, a blood loss of 450 ml accelerates coagulation, and this is further accentuated when blood loss is 900 ml. PMID:24732173

  18. [Evaluation of the severity course and prognosis of disseminated intravascular blood coagulation syndrome].

    PubMed

    Kinakh, M V; Chaplyk, V V; Fedchyshyn, N R

    2009-01-01

    Activation of the peroxidal oxidation of lipids (POL) processes with its primary and secondary products levels raising constitutes a favourable sign, according to data of examination of 66 patients, suffering different phases of disseminated intravascular blood coagulation syndrome (DIBCS). The POL products contents reduction (areactive course) characterizes the process severity and constitutes an unfavourable prognostical sign. The areactive course rate is the highest in the patients, suffering DIBCS, phase III.

  19. Origin of Serpin-Mediated Regulation of Coagulation and Blood Pressure

    PubMed Central

    Wang, Yunjie; Köster, Katharina; Lummer, Martina; Ragg, Hermann

    2014-01-01

    Vertebrates evolved an endothelium-lined hemostatic system and a pump-driven pressurized circulation with a finely-balanced coagulation cascade and elaborate blood pressure control over the past 500 million years. Genome analyses have identified principal components of the ancestral coagulation system, however, how this complex trait was originally regulated is largely unknown. Likewise, little is known about the roots of blood pressure control in vertebrates. Here we studied three members of the serpin superfamily that interfere with procoagulant activity and blood pressure of lampreys, a group of basal vertebrates. Angiotensinogen from these jawless fish was found to fulfill a dual role by operating as a highly selective thrombin inhibitor that is activated by heparin-related glycosaminoglycans, and concurrently by serving as source of effector peptides that activate type 1 angiotensin receptors. Lampreys, uniquely among vertebrates, thus use angiotensinogen for interference with both coagulation and osmo- and pressure regulation. Heparin cofactor II from lampreys, in contrast to its paralogue angiotensinogen, is preferentially activated by dermatan sulfate, suggesting that these two serpins affect different facets of thrombin’s multiple roles. Lampreys also express a lineage-specific serpin with anti-factor Xa activity, which demonstrates that another important procoagulant enzyme is under inhibitory control. Comparative genomics suggests that orthologues of these three serpins were key components of the ancestral hemostatic system. It appears that, early in vertebrate evolution, coagulation and osmo- and pressure regulation crosstalked through antiproteolytically active angiotensinogen, a feature that was lost during vertebrate radiation, though in gnathostomes interplay between these traits is effective. PMID:24840053

  20. Changes in blood coagulation-related parameters in phenobarbital-treated rabbits.

    PubMed

    Mochizuki, Masahiro; Abe, Hajime; Wakabayashi, Kei; Yoshinaga, Hiroyasu; Okazaki, Emi; Saito, Tsubasa; Fujita, Mariko; Edamoto, Hiroshi; Asano, Yuzo

    2009-10-01

    The effects of repeated administration of phenobarbital (PB) on blood coagulation time were examined using male Japanese white SPF rabbits, which are widely used for toxicological studies. PB was administered to the rabbits by oral gavage for 2 weeks, at dose levels of 0, 12.5, 25 and 50 mg/kg/day. Blood was collected on Days 8 and 14 after each day's dosing to perform blood coagulation examination. The liver was excised, weighed and examined histopathologically. Activated partial thromboplastin time (APTT) was prolonged at dose levels of 12.5 mg/kg/day or more and Thrombotest (TBT) was prolonged at 50 mg/kg/day on Day 8. APTT was prolonged at dose levels of 12.5 mg/kg/day or more, TBT was prolonged at 25 mg/kg/day or more and factor IX activity decreased at 50 mg/kg/day on Day 14. At pathological examination, liver weight increased at dose levels of 25 mg/kg/day or more, and a ground-glass appearance of the hepatocytes was observed in the central and middle parts of lobules at 12.5 mg/kg/day or more. However, changes in factor VII or X activity or prolongation of prothrombin time (PT) were not observed. Therefore, prolongation of blood coagulation time by PB administration in rabbits was considered to be due to PB's effect on the endogenous pathway alone. Moreover, an increase in anti-thrombin III (ATIII) concentration was noted at 50 mg/kg/day; however, no change was noted at dose levels of 25 mg/kg/day or less. This suggests that the contribution of ATIII to the PB-induced prolongation of coagulation time in rabbits was small.

  1. Quantitative plasma proteome analysis reveals aberrant level of blood coagulation-related proteins in nasopharyngeal carcinoma.

    PubMed

    Peng, Pei-Hua; Wu, Chih-Ching; Liu, Shu-Chen; Chang, Kai-Ping; Chen, Chi-De; Chang, Ya-Ting; Hsu, Chia-Wei; Chang, Yu-Sun; Yu, Jau-Song

    2011-05-01

    Nasopharyngeal carcinoma (NPC), one of the most common cancers in Southeast Asia, is not easily diagnosed until advanced stages. To discover potential biomarkers for improving NPC diagnosis, we herein identified the aberrant plasma proteins in NPC patients. We first removed the top-seven abundant proteins from plasma samples of healthy controls and NPC patients, and then labeled the samples with different fluorescent cyanine dyes. The labeled samples were then mixed equally and fractionated with ion-exchange chromatography followed by SDS-PAGE. Proteins showing altered levels in NPC patients were identified by in-gel tryptic digestion and LC-MS/MS. When the biological roles of the 45 identified proteins were assessed via MetaCore™ analysis, the blood coagulation pathway emerged as the most significantly altered pathway in NPC plasma. Plasma kallikrein (KLKB1) and thrombin-antithrombin III complex (TAT) were chosen for evaluation as the candidate NPC biomarkers because of their involvement in blood coagulation. ELISAs confirmed the elevation of their plasma levels in NPC patients versus healthy controls. Western blot and activity assays further showed that the KLKB1 active form was significantly increased in NPC plasma. Collectively, our results identified the significant alteration of blood coagulation pathway in NPC patients, and KLKB1 and TAT may represent the potential NPC biomarkers.

  2. Blood plasma coagulation studied by surface plasmon resonance

    NASA Astrophysics Data System (ADS)

    Vikinge, Trine P.; Hansson, Kenny M.; Benesch, Johan; Johansen, Knut; Ranby, Mats; Lindahl, Tomas L.; Lundstroem, Ingemar; Tengvall, Pentti

    1999-01-01

    A surface plasmon resonance (SPR) apparatus was used to investigate blood plasma coagulation in real-time as a function of thromboplastin and heparin concentrations. The physical reason for the SPR signal observed is discussed and 3 different models are proposed. The response curves were analyzed by multivariable curve fitting followed by feature extraction. Interesting parameters of the sigmoid curves were lag time, slope and maximum response. When thromboplastin concentrations were increased, the lag-time decreased and the slope of the curve increased. A prolonged clotting time was followed mostly by increased maximum response, with exception for samples with no or very little thromboplastin added. High heparin concentrations changed the clotting kinetics. As seen from the lag-time vs. slope relation. Atomic force microscopy pictures of sensor surfaces dried after completed clotting, revealed differences in fibrin network structures as a function of thromboplastin concentration, and fiber thickness increased with lower thromboplastin concentration. The results correlate well with present common methods.

  3. Measurement of Blood Coagulation Factor Synthesis in Cultures of Human Hepatocytes.

    PubMed

    Heinz, Stefan; Braspenning, Joris

    2015-01-01

    An important function of the liver is the synthesis and secretion of blood coagulation factors. Within the liver, hepatocytes are involved in the synthesis of most blood coagulation factors, such as fibrinogen, prothrombin, factor V, VII, IX, X, XI, XII, as well as protein C and S, and antithrombin, whereas liver sinusoidal endothelial cells produce factor VIII and von Willebrand factor. Here, we describe methods for the detection and quantification of most blood coagulation factors in hepatocytes in vitro. Hepatocyte cultures indeed provide a valuable tool to study blood coagulation factors. In addition, the generation and expansion of hepatocytes or hepatocyte-like cells may be used in future for cell-based therapies of liver diseases, including blood coagulation factor deficiencies.

  4. [Evaluation of the blood coagulation system after surgeries on abdominal aortic aneurysms].

    PubMed

    Nikul'nikov, P I; Liksunov, O V; Ratushniuk, A V; Lugovs'koĭ, E V; Kolesnikova, I M; Lytvynova, L M; Kostiuchenko, O P; Chernyshenko, T M; Hornyts'ka, O V; Platonova, T M

    2012-09-01

    Basing on data of analysis of the hemostasis system state in the patients, suffering abdominal aorta aneurysm, a tendency for raising of postoperative soluble fibrin and D-dimer content in the blood plasm and reduction of these indices on the third day was noted. The abovementioned markers content depends on the aneurysm size, the fibrin deposits presence, the terms from clinical signs beginning to the certain therapy administration and anticoagulants application. Information about correlation between content of D-dimer and soluble fibrin in the treatment dynamics is important for determination of activation degree in the patients blood coagulation system and the thrombotic complications prognosis.

  5. Monitoring the blood coagulation process under various flow conditions with optical coherence tomography.

    PubMed

    Xu, Xiangqun; Geng, Jinhai; Teng, Xiangshuai

    2014-04-01

    Our previous work demonstrated that an optical coherence tomography (OCT) technique was able to characterize the whole blood coagulation process. The 1/e light penetration depth (d(1/e)) derived from the profiles of reflectance versus depth was developed for detecting the whole blood coagulation process in static state. To consider the effect of blood flow, in the present study, d(1/e) versus time from the coagulating porcine blood circulated in a mock flow loop with various steady laminar flows at mean flow speed in the range from 5 to 25  mm/s. The variation of d(1/e) was used to represent the change of blood properties during coagulation in different hematocrits (HCT) ranging from 25% to 55%, velocities from 5 to 25  mm/s, and tubing sizes from 0.9 to 2 mm. The results showed that there were positive correlations between coagulation time (t(c)) and HCT, velocity, and tubing size, respectively. In addition, the coagulation rate (S(r)) was decreased with the increase of HCT, velocity, and tubing size. This study testified that HCT, flow velocity, and tubing size were substantial factors affecting the backscattering properties during flowing blood coagulation. Furthermore, OCT has the potential to represent the process of flowing blood coagulation with proper parameters.

  6. Blood coagulation profiling in patients using optical thromboelastography (OTEG) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Tripathi, Markandey M.; Tshikudi, Diane M.; Hajjarian, Zeinab; Van Cott, Elizabeth M.; Nadkarni, Seemantini K.

    2016-02-01

    Impaired blood coagulation is often associated with increased postoperative mortality and morbidity in cardiovascular patients. The capability for blood coagulation profiling rapidly at the bedside will enable the timely detection of coagulation defects and open the opportunity for tailoring therapy to correct specific coagulation deficits Optical Thromboelastography (OTEG), is an optical approach to quantify blood coagulation status within minutes using a few drops of whole blood. The goal of the current study is to evaluate the diagnostic accuracy of OTEG for rapid coagulation profiling in patients. In OTEG, temporal laser speckle intensity fluctuations from a drop of clotting blood are measured using a CMOS camera. To quantify coagulation status, the speckle intensity autocorrelation function is measured, the mean square displacement of scattering particles is extracted, and viscoelastic modulus (G), during coagulation is measured via the generalized Stokes-Einstein relation. By quantifying time-resolved changes in G, the coagulation parameters, reaction time (R), clot progression time (K), clot progression rate (Angle), and maximum clot strength (MA) are derived. In this study, the above coagulation parameters were measured using OTEG in 269 patients and compared with standard mechanical Thromboelastography (TEG). Our results showed a strong correlation between OTEG and TEG measurements for all parameters: R-time (R=0.80, p<0.001), clotting time (R=0.78, p<0.001), Angle (R=0.58, p<0.001), and MA (R=0.60, p<0.001). These results demonstrate the unique capability of OTEG for rapid quantification of blood coagulation status to potentially improve clinical capability for identifying impaired coagulation in cardiovascular patients at the point of care.

  7. Characterization of Blood Properties from Coagulating Blood of Different Hematocrits Using Ultrasonic Backscatter and Attenuation

    NASA Astrophysics Data System (ADS)

    Huang, Chih-Chung; Wang, Shyh-Hau

    2006-09-01

    The influence of hematocrit on the change of blood properties during coagulating was extensively investigated using ultrasonic integrated backscatter and attenuation. Measurements were performed with porcine blood at hematocrits ranging from 25 to 55% using a 10 MHz transducer. Results showed that both integrated backscatter and attenuation are able to sensitively differentiate various stages of blood properties during coagulating. The slopes of integrated backscatter (Sr, dB/S) and attenuation (αr, dB\\cdotcm-1\\cdotMHz-1\\cdotmS-1) are increased relative to hematocrit. The best fits for Sr and αr as a function of hematocrit (H) equal to Sr=0.0357+1.62e-0.108H and αr=0.0281+0.003H, respectively. Variations of clotting time (Ts) and reaction time (Tα), estimated respectively from ultrasonic integrated backscatter and attenuation, associated with clot formation are also increased with hematocrit. This study demonstrates that blood hematocrit is a substantial factor affecting viscosity and backscattering properties of blood during coagulation capable of being discerned by ultrasonic backscattering and attenuation.

  8. Differential action of medically important Indian BIG FOUR snake venoms on rodent blood coagulation.

    PubMed

    Hiremath, Vilas; Nanjaraj Urs, A N; Joshi, Vikram; Suvilesh, K N; Savitha, M N; Urs Amog, Prathap; Rudresha, G V; Yariswamy, M; Vishwanath, B S

    2016-02-01

    Snakebite is a global health problem affecting millions of people. According to WHO, India has the highest mortality and/or morbidity due to snakebite. In spite of commendable research on Indian BIG FOUR venomous species; Naja naja and Bungarus caeruleus (elapid); Daboia russelii and Echis carinatus (viperid), no significant progress has been achieved in terms of diagnosis and management of biting species with appropriate anti-snake venom. Major hurdle is identification of offending species. Present study aims at differentiation of Indian BIG FOUR snake venoms based on their distinguish action on rodent blood coagulation. Assessment of coagulation alterations by elapid venoms showed negligible effect on re-calcification time, prothrombin time, activated partial thromboplastin time and factors assay (I, II, V, VIII and X) both in vitro and in vivo. However, viperid venoms demonstrated significant anticoagulant status due to their remarkable fibrinogen degradation potentials as supported by fibrinogenolytic activity, fibrinogen zymography and rotational thromboelastometry. Though results provide hint on probable alterations of Indian BIG FOUR snake venoms on blood coagulation, the study however needs validation from human victim's samples to ascertain its reliability for identification of biting snake species.

  9. The Organophosphate Paraoxon and Its Antidote Obidoxime Inhibit Thrombin Activity and Affect Coagulation In Vitro

    PubMed Central

    Golderman, Valery; Shavit-Stein, Efrat; Tamarin, Ilia; Rosman, Yossi; Shrot, Shai; Rosenberg, Nurit

    2016-01-01

    Organophosphates (OPs) are potentially able to affect serine proteases by reacting with their active site. The potential effects of OPs on coagulation factors such as thrombin and on coagulation tests have been only partially characterized and potential interactions with OPs antidotes such as oximes and muscarinic blockers have not been addressed. In the current study, we investigated the in vitro interactions between coagulation, thrombin, the OP paraoxon, and its antidotes obidoxime and atropine. The effects of these substances on thrombin activity were measured in a fluorescent substrate and on coagulation by standard tests. Both paraoxon and obidoxime but not atropine significantly inhibited thrombin activity, and prolonged prothrombin time, thrombin time, and partial thromboplastin time. When paraoxon and obidoxime were combined, a significant synergistic effect was found on both thrombin activity and coagulation tests. In conclusion, paraoxon and obidoxime affect thrombin activity and consequently alter the function of the coagulation system. Similar interactions may be clinically relevant for coagulation pathways in the blood and possibly in the brain. PMID:27689805

  10. Analysis of the coagulation of human blood cells on diamond surfaces by atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Baranauskas, V.; Fontana, M.; Guo, Zhao Jing; Ceragioli, H. J.; Peterlevitz, A. C.

    2004-11-01

    Atomic force microscopy (AFM) was used to study the morphology and coagulation of human blood cells in contact with solid surfaces. Blood was extracted from the veins of healthy adult donors and the samples were used immediately after extraction, deposited either on borosilicate glass or diamond substrates. Some blood samples were anti-coagulated by adding heparin for single cell AFM imaging. No chemicals were used for attaching or immobilizing the cells. The diamond substrates were produced by chemical vapour deposition (CVD diamond) using a hot-filament CVD system fed with ethanol highly diluted in hydrogen. AFM imaging of isolated cells (anti-coagulated by heparin) was only possible on the glass substrates due to the lack of adherence of the cells to the diamond surface. The coagulation results suggest that blood clotting on diamond produces a less rough surface than blood clotting on glass.

  11. Coagulation factor X activates innate immunity to human species C adenovirus.

    PubMed

    Doronin, Konstantin; Flatt, Justin W; Di Paolo, Nelson C; Khare, Reeti; Kalyuzhniy, Oleksandr; Acchione, Mauro; Sumida, John P; Ohto, Umeharu; Shimizu, Toshiyuki; Akashi-Takamura, Sachiko; Miyake, Kensuke; MacDonald, James W; Bammler, Theo K; Beyer, Richard P; Farin, Frederico M; Stewart, Phoebe L; Shayakhmetov, Dmitry M

    2012-11-01

    Although coagulation factors play a role in host defense for "living fossils" such as horseshoe crabs, the role of the coagulation system in immunity in higher organisms remains unclear. We modeled the interface of human species C adenovirus (HAdv) interaction with coagulation factor X (FX) and introduced a mutation that abrogated formation of the HAdv-FX complex. In vivo genome-wide transcriptional profiling revealed that FX-binding-ablated virus failed to activate a distinct network of nuclear factor κB-dependent early-response genes that are activated by HAdv-FX complex downstream of TLR4/MyD88/TRIF/TRAF6 signaling. Our study implicates host factor "decoration" of the virus as a mechanism to trigger an innate immune sensor that responds to a misplacement of coagulation FX from the blood into intracellular macrophage compartments upon virus entry into the cell. PMID:23019612

  12. A sample-to-result system for blood coagulation tests on a microfluidic disk analyzer.

    PubMed

    Lin, Chia-Hui; Liu, Cheng-Yuan; Shih, Chih-Hsin; Lu, Chien-Hsing

    2014-09-01

    In this report, we describe in detail a microfluidic analyzer, which is able to conduct blood coagulation tests using whole blood samples. Sample preparation steps, such as whole blood aliquoting and metering, plasma separation, decanting, and mixing with reagents were performed in sequence through microfluidic functions integrated on a disk. Both prothrombin time (PT) and activated partial thromboplastin time (aPTT) were carried out on the same platform and the test results can be reported in 5 min. Fifty clinical samples were tested for both PT and aPTT utilizing the microfluidic disk analyzer and the instrument used in hospitals. The test results showed good correlation and agreement between the two instruments.

  13. A sample-to-result system for blood coagulation tests on a microfluidic disk analyzer

    PubMed Central

    Lin, Chia-Hui; Liu, Cheng-Yuan; Shih, Chih-Hsin; Lu, Chien-Hsing

    2014-01-01

    In this report, we describe in detail a microfluidic analyzer, which is able to conduct blood coagulation tests using whole blood samples. Sample preparation steps, such as whole blood aliquoting and metering, plasma separation, decanting, and mixing with reagents were performed in sequence through microfluidic functions integrated on a disk. Both prothrombin time (PT) and activated partial thromboplastin time (aPTT) were carried out on the same platform and the test results can be reported in 5 min. Fifty clinical samples were tested for both PT and aPTT utilizing the microfluidic disk analyzer and the instrument used in hospitals. The test results showed good correlation and agreement between the two instruments. PMID:25332733

  14. Purification and characterization of a heteromultimeric glycoprotein from Artocarpus heterophyllus latex with an inhibitory effect on human blood coagulation.

    PubMed

    Siritapetawee, Jaruwan; Thammasirirak, Sompong

    2011-01-01

    Plant latex has many health benefits and has been used in folk medicine. In this study, the biological effect of Artocarpus heterophyllus (jackfruit) latex on human blood coagulation was investigated. By a combination of heat precipitation and ion-exchange chromatography, a heat stable heteromultimeric glycoprotein (HSGPL1) was purified from jackfruit milky latex. The apparent molecular masses of the monomeric proteins on SDS/PAGE were 33, 31 and 29 kDa. The isoelectric points (pIs) of the monomers were 6.63, 6.63 and 6.93, respectively. Glycosylation and deglycosylation tests confirmed that each subunit of HSGPL1 formed the native multimer by sugar-based interaction. Moreover, the multimer of HSGPL1 also resisted 2-mercaptoethanol action. Peptide mass fingerprint analysis indicated that HSGPL1 was a complex protein related to Hsps/chaperones. HSGPL1 has an effect on intrinsic pathways of the human blood coagulation system by significantly prolonging the activated partial thrombin time (APTT). In contrast, it has no effect on the human extrinsic blood coagulation system using the prothrombin time (PT) test. The prolonged APTT resulted from the serine protease inhibitor property of HSGPL1, since it reduced activity of human blood coagulation factors XI(a) and α-XII(a).

  15. Influence of a constant and variable magnetic field on the coagulation of human blood in vitro and in vivo

    NASA Technical Reports Server (NTRS)

    Degen, I. L.; Plaksenko, V. Y.

    1974-01-01

    The influence of constant and varying magnetic fields on the coagulation of the blood was studied in experiments performed in vitro and vivo. In the in vitro tests it was found that a constant magnetic field with a strength of 100 or 200 oersteds influences the coagulation of the blood, retarding it in some cases and speeding up the coagulation time in others. In the in vivo studies, both retarding and accelerating effects were likewise observed with respect to the coagulation of the blood, but the nature of the change was a function of the background. A normalizing effect of the magnetic field on the coagulation of the blood was observed.

  16. [The effects of Arnica Montana on blood coagulation. Randomized controlled trial].

    PubMed

    Baillargeon, L; Drouin, J; Desjardins, L; Leroux, D; Audet, D

    1993-11-01

    The purpose of this study, which took the form of a two-period cross-over clinical trial, was to determine whether a homeopathic substance, Arnica Montana, significantly decreased bleeding time (Simplate II) and to describe its impact on various blood coagulation tests. It was not shown that this substance had a significant impact on various parameters of blood coagulation in healthy volunteers in the period immediately following administration [corrected].

  17. Real-time electrical impedimetric monitoring of blood coagulation process under temperature and hematocrit variations conducted in a microfluidic chip.

    PubMed

    Lei, Kin Fong; Chen, Kuan-Hao; Tsui, Po-Hsiang; Tsang, Ngan-Ming

    2013-01-01

    Blood coagulation is an extremely complicated and dynamic physiological process. Monitoring of blood coagulation is essential to predict the risk of hemorrhage and thrombosis during cardiac surgical procedures. In this study, a high throughput microfluidic chip has been developed for the investigation of the blood coagulation process under temperature and hematocrit variations. Electrical impedance of the whole blood was continuously recorded by on-chip electrodes in contact with the blood sample during coagulation. Analysis of the impedance change of the blood was conducted to investigate the characteristics of blood coagulation process and the starting time of blood coagulation was defined. The study of blood coagulation time under temperature and hematocrit variations was shown a good agreement with results in the previous clinical reports. The electrical impedance measurement for the definition of blood coagulation process provides a fast and easy measurement technique. The microfluidic chip was shown to be a sensitive and promising device for monitoring blood coagulation process even in a variety of conditions. It is found valuable for the development of point-of-care coagulation testing devices that utilizes whole blood sample in microliter quantity.

  18. Metalloproteases Affecting Blood Coagulation, Fibrinolysis and Platelet Aggregation from Snake Venoms: Definition and Nomenclature of Interaction Sites

    PubMed Central

    Kini, R. Manjunatha; Koh, Cho Yeow

    2016-01-01

    Snake venom metalloproteases, in addition to their contribution to the digestion of the prey, affect various physiological functions by cleaving specific proteins. They exhibit their activities through activation of zymogens of coagulation factors, and precursors of integrins or receptors. Based on their structure–function relationships and mechanism of action, we have defined classification and nomenclature of functional sites of proteases. These metalloproteases are useful as research tools and in diagnosis and treatment of various thrombotic and hemostatic conditions. They also contribute to our understanding of molecular details in the activation of specific factors involved in coagulation, platelet aggregation and matrix biology. This review provides a ready reference for metalloproteases that interfere in blood coagulation, fibrinolysis and platelet aggregation. PMID:27690102

  19. Blood coagulation and fibrinolysis in aortic valve stenosis: links with inflammation and calcification.

    PubMed

    Natorska, J; Undas, A

    2015-08-01

    Aortic valve stenosis (AS) increasingly afflicts our aging population. However, the pathobiology of the disease is still poorly understood and there is no effective pharmacotherapy for treating those at risk for clinical progression. The progression of AS involves complex inflammatory and fibroproliferative processes that resemble to some extent atherosclerosis. Accumulating evidence indicates that several coagulation proteins and its inhibitors, including tissue factor, tissue factor pathway inhibitor, prothrombin, factor XIII, von Willebrand factor, display increased expression within aortic stenotic valves, predominantly on macrophages and myofibroblasts around calcified areas. Systemic impaired fibrinolysis, along with increased plasma and valvular expression of plasminogen activator inhibitor-1, has also been observed in patients with AS in association with the severity of the disease. There is an extensive cross-talk between inflammation and coagulation in stenotic valve tissue which contributes to the calcification and mineralisation of the aortic valve leaflets. This review summarises the available data on blood coagulation and fibrinolysis in AS with the emphasis on their interactions with inflammation and calcification.

  20. CARDIOVASCULAR AND BLOOD COAGULATION EFFECTS OF PULMONARY ZINC EXPOSURE

    EPA Science Inventory

    Cardiovascular damage induced by pulmonary exposure to environmental chemicals can result from direct action or, secondarily, from pulmonary injury. We have developed a rat model of pulmonary exposure to zinc to demonstrate cardiac, coagulative, and fibrinolytic alterations. Mal...

  1. Disequilibrium of Blood Coagulation and Fibrinolytic System in Patients With Coronary Artery Ectasia.

    PubMed

    Wu, Wei; Liu, Ruifeng; Chen, Lianfeng; Chen, Houzao; Zhang, Shuyang

    2016-02-01

    Thrombus formation and myocardial infarction are not uncommon in patients with coronary artery ectasia (CAE). In light of this, the present study aims to systemically evaluate the blood coagulation and fibrinolytic systems in CAE patients. In this study, we enrolled 30 patients with CAE, 30 patients with coronary atherosclerosis disease (CAD), and 29 subjects with normal coronary arteries (control). The coagulation system was evaluated using a routine coagulation function test performed in the hospital laboratory before coronary angiography, and measurements included prothrombin time, international normalized ratio, activated partial thromboplastin time, fibrinogen time, and thrombin time. The evaluation of the fibrinolytic system included measurements of D-dimer, euglobulin lysis time, plasminogen activator inhibitor 1, plasminogen, plasminogen activity assay, α1-antitrypsin (α1-AT), α2 plasmin inhibitor (α2-PI), and α2-macroglobulin (α2-MG). Alpha1-AT, α2-PI, and α2-MG also inhibit activities of 3 neutrophil serine proteases, namely human neutrophil elastase (HNE), cathepsin G (CG), and proteinase 3 (PR3); therefore, the plasma levels of these 3 proteinases were also evaluated.In CAE patients, the circulating coagulation system was normal. For the fibrinolytic system, a decrease of plasminogen activity was observed (P = 0.029) when compared with CAD patients, and the concentrations of α1-AT (both P < 0.001), α2-PI (P = 0.002 and P = 0.025), and α2-MG (P = 0.034 and P < 0.001) were significantly elevated when compared with CAD patients and normal controls. Moreover, the plasma levels of HNE (both P < 0.001) and CG (P = 0.027 and 0.016) in CAE patients were also significantly higher than those of the CAD and control groups. There was no difference in plasma PR3 concentration among these 3 groups.Disequilibrium of the coagulation/fibrinolytic system may contribute to thrombus formation and clinical coronary events in

  2. Disequilibrium of Blood Coagulation and Fibrinolytic System in Patients With Coronary Artery Ectasia

    PubMed Central

    Wu, Wei; Liu, Ruifeng; Chen, Lianfeng; Chen, Houzao; Zhang, Shuyang

    2016-01-01

    Abstract Thrombus formation and myocardial infarction are not uncommon in patients with coronary artery ectasia (CAE). In light of this, the present study aims to systemically evaluate the blood coagulation and fibrinolytic systems in CAE patients. In this study, we enrolled 30 patients with CAE, 30 patients with coronary atherosclerosis disease (CAD), and 29 subjects with normal coronary arteries (control). The coagulation system was evaluated using a routine coagulation function test performed in the hospital laboratory before coronary angiography, and measurements included prothrombin time, international normalized ratio, activated partial thromboplastin time, fibrinogen time, and thrombin time. The evaluation of the fibrinolytic system included measurements of D-dimer, euglobulin lysis time, plasminogen activator inhibitor 1, plasminogen, plasminogen activity assay, α1-antitrypsin (α1-AT), α2 plasmin inhibitor (α2-PI), and α2-macroglobulin (α2-MG). Alpha1-AT, α2-PI, and α2-MG also inhibit activities of 3 neutrophil serine proteases, namely human neutrophil elastase (HNE), cathepsin G (CG), and proteinase 3 (PR3); therefore, the plasma levels of these 3 proteinases were also evaluated. In CAE patients, the circulating coagulation system was normal. For the fibrinolytic system, a decrease of plasminogen activity was observed (P = 0.029) when compared with CAD patients, and the concentrations of α1-AT (both P < 0.001), α2-PI (P = 0.002 and P = 0.025), and α2-MG (P = 0.034 and P < 0.001) were significantly elevated when compared with CAD patients and normal controls. Moreover, the plasma levels of HNE (both P < 0.001) and CG (P = 0.027 and 0.016) in CAE patients were also significantly higher than those of the CAD and control groups. There was no difference in plasma PR3 concentration among these 3 groups. Disequilibrium of the coagulation/fibrinolytic system may contribute to thrombus formation and clinical coronary

  3. Disequilibrium of Blood Coagulation and Fibrinolytic System in Patients With Coronary Artery Ectasia.

    PubMed

    Wu, Wei; Liu, Ruifeng; Chen, Lianfeng; Chen, Houzao; Zhang, Shuyang

    2016-02-01

    Thrombus formation and myocardial infarction are not uncommon in patients with coronary artery ectasia (CAE). In light of this, the present study aims to systemically evaluate the blood coagulation and fibrinolytic systems in CAE patients. In this study, we enrolled 30 patients with CAE, 30 patients with coronary atherosclerosis disease (CAD), and 29 subjects with normal coronary arteries (control). The coagulation system was evaluated using a routine coagulation function test performed in the hospital laboratory before coronary angiography, and measurements included prothrombin time, international normalized ratio, activated partial thromboplastin time, fibrinogen time, and thrombin time. The evaluation of the fibrinolytic system included measurements of D-dimer, euglobulin lysis time, plasminogen activator inhibitor 1, plasminogen, plasminogen activity assay, α1-antitrypsin (α1-AT), α2 plasmin inhibitor (α2-PI), and α2-macroglobulin (α2-MG). Alpha1-AT, α2-PI, and α2-MG also inhibit activities of 3 neutrophil serine proteases, namely human neutrophil elastase (HNE), cathepsin G (CG), and proteinase 3 (PR3); therefore, the plasma levels of these 3 proteinases were also evaluated.In CAE patients, the circulating coagulation system was normal. For the fibrinolytic system, a decrease of plasminogen activity was observed (P = 0.029) when compared with CAD patients, and the concentrations of α1-AT (both P < 0.001), α2-PI (P = 0.002 and P = 0.025), and α2-MG (P = 0.034 and P < 0.001) were significantly elevated when compared with CAD patients and normal controls. Moreover, the plasma levels of HNE (both P < 0.001) and CG (P = 0.027 and 0.016) in CAE patients were also significantly higher than those of the CAD and control groups. There was no difference in plasma PR3 concentration among these 3 groups.Disequilibrium of the coagulation/fibrinolytic system may contribute to thrombus formation and clinical coronary events in

  4. Optical coherence tomography-guided laser microsurgery for blood coagulation with continuous-wave laser diode

    PubMed Central

    Chang, Feng-Yu; Tsai, Meng-Tsan; Wang, Zu-Yi; Chi, Chun-Kai; Lee, Cheng-Kuang; Yang, Chih-Hsun; Chan, Ming-Che; Lee, Ya-Ju

    2015-01-01

    Blood coagulation is the clotting and subsequent dissolution of the clot following repair to the damaged tissue. However, inducing blood coagulation is difficult for some patients with homeostasis dysfunction or during surgery. In this study, we proposed a method to develop an integrated system that combines optical coherence tomography (OCT) and laser microsurgery for blood coagulation. Also, an algorithm for positioning of the treatment location from OCT images was developed. With OCT scanning, 2D/3D OCT images and angiography of tissue can be obtained simultaneously, enabling to noninvasively reconstruct the morphological and microvascular structures for real-time monitoring of changes in biological tissues during laser microsurgery. Instead of high-cost pulsed lasers, continuous-wave laser diodes (CW-LDs) with the central wavelengths of 450 nm and 532 nm are used for blood coagulation, corresponding to higher absorption coefficients of oxyhemoglobin and deoxyhemoglobin. Experimental results showed that the location of laser exposure can be accurately controlled with the proposed approach of imaging-based feedback positioning. Moreover, blood coagulation can be efficiently induced by CW-LDs and the coagulation process can be monitored in real-time with OCT. This technology enables to potentially provide accurate positioning for laser microsurgery and control the laser exposure to avoid extra damage by real-time OCT imaging. PMID:26568136

  5. Optical coherence tomography-guided laser microsurgery for blood coagulation with continuous-wave laser diode

    NASA Astrophysics Data System (ADS)

    Chang, Feng-Yu; Tsai, Meng-Tsan; Wang, Zu-Yi; Chi, Chun-Kai; Lee, Cheng-Kuang; Yang, Chih-Hsun; Chan, Ming-Che; Lee, Ya-Ju

    2015-11-01

    Blood coagulation is the clotting and subsequent dissolution of the clot following repair to the damaged tissue. However, inducing blood coagulation is difficult for some patients with homeostasis dysfunction or during surgery. In this study, we proposed a method to develop an integrated system that combines optical coherence tomography (OCT) and laser microsurgery for blood coagulation. Also, an algorithm for positioning of the treatment location from OCT images was developed. With OCT scanning, 2D/3D OCT images and angiography of tissue can be obtained simultaneously, enabling to noninvasively reconstruct the morphological and microvascular structures for real-time monitoring of changes in biological tissues during laser microsurgery. Instead of high-cost pulsed lasers, continuous-wave laser diodes (CW-LDs) with the central wavelengths of 450 nm and 532 nm are used for blood coagulation, corresponding to higher absorption coefficients of oxyhemoglobin and deoxyhemoglobin. Experimental results showed that the location of laser exposure can be accurately controlled with the proposed approach of imaging-based feedback positioning. Moreover, blood coagulation can be efficiently induced by CW-LDs and the coagulation process can be monitored in real-time with OCT. This technology enables to potentially provide accurate positioning for laser microsurgery and control the laser exposure to avoid extra damage by real-time OCT imaging.

  6. Optical coherence tomography-guided laser microsurgery for blood coagulation with continuous-wave laser diode.

    PubMed

    Chang, Feng-Yu; Tsai, Meng-Tsan; Wang, Zu-Yi; Chi, Chun-Kai; Lee, Cheng-Kuang; Yang, Chih-Hsun; Chan, Ming-Che; Lee, Ya-Ju

    2015-11-16

    Blood coagulation is the clotting and subsequent dissolution of the clot following repair to the damaged tissue. However, inducing blood coagulation is difficult for some patients with homeostasis dysfunction or during surgery. In this study, we proposed a method to develop an integrated system that combines optical coherence tomography (OCT) and laser microsurgery for blood coagulation. Also, an algorithm for positioning of the treatment location from OCT images was developed. With OCT scanning, 2D/3D OCT images and angiography of tissue can be obtained simultaneously, enabling to noninvasively reconstruct the morphological and microvascular structures for real-time monitoring of changes in biological tissues during laser microsurgery. Instead of high-cost pulsed lasers, continuous-wave laser diodes (CW-LDs) with the central wavelengths of 450 nm and 532 nm are used for blood coagulation, corresponding to higher absorption coefficients of oxyhemoglobin and deoxyhemoglobin. Experimental results showed that the location of laser exposure can be accurately controlled with the proposed approach of imaging-based feedback positioning. Moreover, blood coagulation can be efficiently induced by CW-LDs and the coagulation process can be monitored in real-time with OCT. This technology enables to potentially provide accurate positioning for laser microsurgery and control the laser exposure to avoid extra damage by real-time OCT imaging.

  7. Dimeric Organization of Blood Coagulation Factor VIII bound to Lipid Nanotubes.

    PubMed

    Dalm, Daniela; Galaz-Montoya, Jesus G; Miller, Jaimy L; Grushin, Kirill; Villalobos, Alex; Koyfman, Alexey Y; Schmid, Michael F; Stoilova-McPhie, Svetla

    2015-01-01

    Membrane-bound Factor VIII (FVIII) has a critical function in blood coagulation as the pro-cofactor to the serine-protease Factor IXa (FIXa) in the FVIIIa-FIXa complex assembled on the activated platelet membrane. Defects or deficiency of FVIII cause Hemophilia A, a mild to severe bleeding disorder. Despite existing crystal structures for FVIII, its membrane-bound organization has not been resolved. Here we present the dimeric FVIII membrane-bound structure when bound to lipid nanotubes, as determined by cryo-electron microscopy. By combining the structural information obtained from helical reconstruction and single particle subtomogram averaging at intermediate resolution (15-20 Å), we show unambiguously that FVIII forms dimers on lipid nanotubes. We also demonstrate that the organization of the FVIII membrane-bound domains is consistently different from the crystal structure in solution. The presented results are a critical step towards understanding the mechanism of the FVIIIa-FIXa complex assembly on the activated platelet surface in the propagation phase of blood coagulation.

  8. Dimeric Organization of Blood Coagulation Factor VIII bound to Lipid Nanotubes

    PubMed Central

    Dalm, Daniela; Galaz-Montoya, Jesus G.; Miller, Jaimy L.; Grushin, Kirill; Villalobos, Alex; Koyfman, Alexey Y.; Schmid, Michael F.; Stoilova-McPhie, Svetla

    2015-01-01

    Membrane-bound Factor VIII (FVIII) has a critical function in blood coagulation as the pro-cofactor to the serine-protease Factor IXa (FIXa) in the FVIIIa-FIXa complex assembled on the activated platelet membrane. Defects or deficiency of FVIII cause Hemophilia A, a mild to severe bleeding disorder. Despite existing crystal structures for FVIII, its membrane-bound organization has not been resolved. Here we present the dimeric FVIII membrane-bound structure when bound to lipid nanotubes, as determined by cryo-electron microscopy. By combining the structural information obtained from helical reconstruction and single particle subtomogram averaging at intermediate resolution (15-20 Å), we show unambiguously that FVIII forms dimers on lipid nanotubes. We also demonstrate that the organization of the FVIII membrane-bound domains is consistently different from the crystal structure in solution. The presented results are a critical step towards understanding the mechanism of the FVIIIa-FIXa complex assembly on the activated platelet surface in the propagation phase of blood coagulation. PMID:26082135

  9. Effect of fibrinogen on blood coagulation detected by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Xu, Xiangqun; Teng, Xiangshuai

    2015-05-01

    Our previous work demonstrated that an optical coherence tomography (OCT) technique and the parameter 1/e light penetration depth (d1/e) were able to characterize the whole blood coagulation process in contrast to existing optical tests that are performed on plasma samples. To evaluate the feasibility of the technique for quantifying the effect of fibrinogen (Fbg) on blood coagulation, a dynamic study of d1/e of blood in various Fbg concentrations was performed in static state. Two groups of blood samples of hematocrit (HCT) in 35, 45, and 55% were reconstituted of red blood cells with: 1) treated plasma with its intrinsic Fbg removed and commercial Fbg added (0-8 g L-1) and 2) native plasma with commercial Fbg added (0-8 g L-1). The results revealed a typical behavior due to coagulation induced by calcium ions and the clotting time is Fbg concentration-dependent. The clotting time was decreased by the increasing amount of Fbg in both groups. Besides, the blood of lower HCT with various levels of Fbg took shorter time to coagulate than that of higher HCT. Consequently, the OCT method is a useful and promising tool for the detection of blood-coagulation processes induced with different Fbg levels.

  10. Effect of fibrinogen on blood coagulation detected by optical coherence tomography.

    PubMed

    Xu, Xiangqun; Teng, Xiangshuai

    2015-05-21

    Our previous work demonstrated that an optical coherence tomography (OCT) technique and the parameter 1/e light penetration depth (d1/e) were able to characterize the whole blood coagulation process in contrast to existing optical tests that are performed on plasma samples. To evaluate the feasibility of the technique for quantifying the effect of fibrinogen (Fbg) on blood coagulation, a dynamic study of d1/e of blood in various Fbg concentrations was performed in static state. Two groups of blood samples of hematocrit (HCT) in 35, 45, and 55% were reconstituted of red blood cells with: 1) treated plasma with its intrinsic Fbg removed and commercial Fbg added (0-8 g L(-1)); and 2) native plasma with commercial Fbg added (0-8 g L(-1)). The results revealed a typical behavior due to coagulation induced by calcium ions and the clotting time is Fbg concentration-dependent. The clotting time was decreased by the increasing amount of Fbg in both groups. Besides, the blood of lower HCT with various levels of Fbg took shorter time to coagulate than that of higher HCT. Consequently, the OCT method is a useful and promising tool for the detection of blood-coagulation processes induced with different Fbg levels.

  11. Metals in air pollution particles decrease whole-blood coagulation time.

    PubMed

    Sangani, Rahul G; Soukup, Joleen M; Ghio, Andrew J

    2010-07-01

    The mechanism underlying procoagulative effects of air pollution particle exposure is not known. The authors tested the postulate that (1) the water-soluble components of an air pollution particle could affect whole-blood coagulation time and (2) metals included in this fraction were responsible for this effect. Exposure to the water-soluble fraction of particulate matter (PM), at doses as low as 50 ng/ml original particle, significantly diminished the whole-blood coagulation time. Inclusion of deferoxamine prolonged coagulation time following the exposures to the water-soluble fraction, whereas equivalent doses of ferroxamine had no effect. Except for nickel, all metal sulfates shortened the whole-blood coagulation time. Iron and zinc were two metals with the greatest capacity to reduce the coagulation time, with an effect observed at 10 ng/ml. Finally, in contrast to the anticoagulants citrate and EDTA, their iron complexes were found to be procoagulative. The authors conclude that metals in the water-soluble fraction of air pollution particles decrease whole-blood coagulation time. These metals can potentially contribute to procoagulative effects observed following human exposures to air pollution particles.

  12. Fusaric acid, a mycotoxin, and its influence on blood coagulation and platelet function.

    PubMed

    Devaraja, Sannaningaiah; Girish, Kesturu S; Santhosh, Martin S; Hemshekhar, Mahadevappa; Nayaka, Siddaiah C; Kemparaju, Kempaiah

    2013-06-01

    The current study intended to explore the effect of fusaric acid on blood coagulation including plasma coagulation and platelet aggregation. Fusaric acid exhibited biphasic effects on citrated human plasma recalcification time. At concentrations below 50 ng, fusaric acid decreased the clotting time of plasma dose-dependently from 130 ± 3s control value to 32 ± 3s; however, above 50 ng, fusaric acid increased the clotting time from 32 ± 3s and reached a maximum of 152 s at 100 ng and remained unaltered thereafter for the increased dose of fusaric acid. Fusaric acid without damaging red blood cells and platelets, inhibited agonists such as collagen, ADP, thrombin, and epinephrine-induced aggregation of both platelet-rich plasma (PRP) and washed platelets preparations of human. Interestingly, fusaric acid showed biphasic effects only in thrombin-induced platelet aggregation of washed platelets, and at lower concentration (below 900 ng) it activated platelet aggregation; however, in increased concentration (above 900 ng) it inhibited the platelet aggregation of washed platelets. In addition, fusaric acid also inhibited the agonist ADP-induced platelet aggregation of washed platelet suspension but did not show biphasic effect. Further, fusaric acid did not induce the platelets to generate reactive oxygen species (ROS) that clearly suggests that the induction of platelet function could be the result of the fusaric acid-mediated receptor interaction but not through the morphological shape change.

  13. Evaluation of the Efficacy and Safety of Rivaroxaban Using a Computer Model for Blood Coagulation

    PubMed Central

    Burghaus, Rolf; Coboeken, Katrin; Gaub, Thomas; Kuepfer, Lars; Sensse, Anke; Siegmund, Hans-Ulrich; Weiss, Wolfgang; Mueck, Wolfgang; Lippert, Joerg

    2011-01-01

    Rivaroxaban is an oral, direct Factor Xa inhibitor approved in the European Union and several other countries for the prevention of venous thromboembolism in adult patients undergoing elective hip or knee replacement surgery and is in advanced clinical development for the treatment of thromboembolic disorders. Its mechanism of action is antithrombin independent and differs from that of other anticoagulants, such as warfarin (a vitamin K antagonist), enoxaparin (an indirect thrombin/Factor Xa inhibitor) and dabigatran (a direct thrombin inhibitor). A blood coagulation computer model has been developed, based on several published models and preclinical and clinical data. Unlike previous models, the current model takes into account both the intrinsic and extrinsic pathways of the coagulation cascade, and possesses some unique features, including a blood flow component and a portfolio of drug action mechanisms. This study aimed to use the model to compare the mechanism of action of rivaroxaban with that of warfarin, and to evaluate the efficacy and safety of different rivaroxaban doses with other anticoagulants included in the model. Rather than reproducing known standard clinical measurements, such as the prothrombin time and activated partial thromboplastin time clotting tests, the anticoagulant benchmarking was based on a simulation of physiologically plausible clotting scenarios. Compared with warfarin, rivaroxaban showed a favourable sensitivity for tissue factor concentration inducing clotting, and a steep concentration–effect relationship, rapidly flattening towards higher inhibitor concentrations, both suggesting a broad therapeutic window. The predicted dosing window is highly accordant with the final dose recommendation based upon extensive clinical studies. PMID:21526168

  14. Evaluation of the efficacy and safety of rivaroxaban using a computer model for blood coagulation.

    PubMed

    Burghaus, Rolf; Coboeken, Katrin; Gaub, Thomas; Kuepfer, Lars; Sensse, Anke; Siegmund, Hans-Ulrich; Weiss, Wolfgang; Mueck, Wolfgang; Lippert, Joerg

    2011-01-01

    Rivaroxaban is an oral, direct Factor Xa inhibitor approved in the European Union and several other countries for the prevention of venous thromboembolism in adult patients undergoing elective hip or knee replacement surgery and is in advanced clinical development for the treatment of thromboembolic disorders. Its mechanism of action is antithrombin independent and differs from that of other anticoagulants, such as warfarin (a vitamin K antagonist), enoxaparin (an indirect thrombin/Factor Xa inhibitor) and dabigatran (a direct thrombin inhibitor). A blood coagulation computer model has been developed, based on several published models and preclinical and clinical data. Unlike previous models, the current model takes into account both the intrinsic and extrinsic pathways of the coagulation cascade, and possesses some unique features, including a blood flow component and a portfolio of drug action mechanisms. This study aimed to use the model to compare the mechanism of action of rivaroxaban with that of warfarin, and to evaluate the efficacy and safety of different rivaroxaban doses with other anticoagulants included in the model. Rather than reproducing known standard clinical measurements, such as the prothrombin time and activated partial thromboplastin time clotting tests, the anticoagulant benchmarking was based on a simulation of physiologically plausible clotting scenarios. Compared with warfarin, rivaroxaban showed a favourable sensitivity for tissue factor concentration inducing clotting, and a steep concentration-effect relationship, rapidly flattening towards higher inhibitor concentrations, both suggesting a broad therapeutic window. The predicted dosing window is highly accordant with the final dose recommendation based upon extensive clinical studies. PMID:21526168

  15. Matriptase activation connects tissue factor-dependent coagulation initiation to epithelial proteolysis and signaling.

    PubMed

    Le Gall, Sylvain M; Szabo, Roman; Lee, Melody; Kirchhofer, Daniel; Craik, Charles S; Bugge, Thomas H; Camerer, Eric

    2016-06-23

    The coagulation cascade is designed to sense tissue injury by physical separation of the membrane-anchored cofactor tissue factor (TF) from inactive precursors of coagulation proteases circulating in plasma. Once TF on epithelial and other extravascular cells is exposed to plasma, sequential activation of coagulation proteases coordinates hemostasis and contributes to host defense and tissue repair. Membrane-anchored serine proteases (MASPs) play critical roles in the development and homeostasis of epithelial barrier tissues; how MASPs are activated in mature epithelia is unknown. We here report that proteases of the extrinsic pathway of blood coagulation transactivate the MASP matriptase, thus connecting coagulation initiation to epithelial proteolysis and signaling. Exposure of TF-expressing cells to factors (F) VIIa and Xa triggered the conversion of latent pro-matriptase to an active protease, which in turn cleaved the pericellular substrates protease-activated receptor-2 (PAR2) and pro-urokinase. An activation pathway-selective PAR2 mutant resistant to direct cleavage by TF:FVIIa and FXa was activated by these proteases when cells co-expressed pro-matriptase, and matriptase transactivation was necessary for efficient cleavage and activation of wild-type PAR2 by physiological concentrations of TF:FVIIa and FXa. The coagulation initiation complex induced rapid and prolonged enhancement of the barrier function of epithelial monolayers that was dependent on matriptase transactivation and PAR2 signaling. These observations suggest that the coagulation cascade engages matriptase to help coordinate epithelial defense and repair programs after injury or infection, and that matriptase may contribute to TF-driven pathogenesis in cancer and inflammation. PMID:27114461

  16. [Relation between biomarkers of the coagulation cascade, fibrinolytic system and lipid profiles in hypertensive patients with various coagulation potential of whole blood].

    PubMed

    Tolstopiatov, S M

    2009-01-01

    227 hypertensive patients, stage II-III have been investigated using new laboratory technology (patent of Ukraine), to reveal signs of coagulation potential and fibrinolytic tests of whole blood. 120 patients have been observed to detect definite markers of lipid profile. Obtained results revealed depression of fibrinolysis (from I to X degree) in 77.3%, hypercoagulation in 53.3%, and hypocoagulation in 25.6% of patients. These multidirectional changes proves the necessity of a laboratory control during administration of antiplatelets drugs. Besides, having coagulation module (CM) at VI-VIII degree, which corresponds to a high clinical risk factor of and urgent situation, the tactics of the treatment should be aggressive and parenteral. Lipid concentration was considerably higher at hypercoagulation state, although in 11-22% of cases, dislipidemia developed at hypocoagulation state. Total cholesterol (TC) and lipoprotein levels do not influence on formation of blood clot and considerably increase its density (P < 0.01), that complicates dissolving of blood clot by the fibrinolytic system, functional state of which goes down additionally during the increase of TC (r = -0.207; P < 0.05) and LDL (r = -0.197; P < 0.05). Fibrinolytic activity has strongly correlated with clot level (r = -0.465; P < 0.0001) and its density (r = -0.393; P < 0.0001). So, the algorithm of an individual treatment should include antihypertensive (under the control Blood Pressure), antiliplatelets (under the control MC) and hypolipidemic (under the laboratory control) agents.

  17. [Role of spatio-temporal non uniformities in blood coagulation regulation].

    PubMed

    Shibeko, A M; Ataullakhanov, F I

    2013-01-01

    This paper reviews some contemporary researches of thrombosis and hemostasis process that consider its spatio-temporal dynamics. Among them, there are platelet distribution in the blood vessel and the dependence of the platelet plug growth on the hematocrit level; influence of the tissue factor density on the blood coagulation onset and on the efficacy of some drugs, designed for the hemostasis improvement; regulation of blood coagulation by the flow rate. Mechanisms controlling the mentioned processes are described. Clinical significance and novel diagnostic and therapeutic approaches are discussed from the position of the spatio-temporal non uniformities of thrombosis and hemosatsis.

  18. Surface-mediated control of blood coagulation: the role of binding site densities and platelet deposition.

    PubMed Central

    Kuharsky, A L; Fogelson, A L

    2001-01-01

    A mathematical model of the extrinsic or tissue factor (TF) pathway of blood coagulation is formulated and results from a computational study of its behavior are presented. The model takes into account plasma-phase and surface-bound enzymes and zymogens, coagulation inhibitors, and activated and unactivated platelets. It includes both plasma-phase and membrane-phase reactions, and accounts for chemical and cellular transport by flow and diffusion, albeit in a simplified manner by assuming the existence of a thin, well-mixed fluid layer, near the surface, whose thickness depends on flow. There are three main conclusions from these studies. (i) The model system responds in a threshold manner to changes in the availability of particular surface binding sites; an increase in TF binding sites, as would occur with vascular injury, changes the system's production of thrombin dramatically. (ii) The model suggests that platelets adhering to and covering the subendothelium, rather than chemical inhibitors, may play the dominant role in blocking the activity of the TF:VIIa enzyme complex. This, in turn, suggests that a role of the IXa-tenase pathway for activating factor X to Xa is to continue factor Xa production after platelets have covered the TF:VIIa complexes on the subendothelium. (iii) The model gives a kinetic explanation of the reduced thrombin production in hemophilias A and B. PMID:11222273

  19. Dry reagent technology for rapid, convenient measurements of blood coagulation and fibrinolysis.

    PubMed

    Oberhardt, B J; Dermott, S C; Taylor, M; Alkadi, Z Y; Abruzzini, A F; Gresalfi, N J

    1991-04-01

    Rapid coagulation and fibrinolysis assays suitable for use with an imprecisely measured sample volume (either whole blood or plasma) have been developed, utilizing a technology based on paramagnetic iron oxide particles (PIOP) that move in response to an oscillating magnetic field. PIOP are combined with appropriate test reagents for clotting and thrombolysis assays and formulated as dry reagents within a capillary test chamber. The minima and maxima of the PIOP oscillations define a two-sided waveform that provides kinetic information on fibrin polymerization and lysis. Subject to the chemistry of the dry reagent formulation, the resulting waveform can be used to define clotting time, lysis onset time, or fibrinogen variables. Applications to one-stage prothrombin time and one-stage activated partial thromboplastin time tests have yielded assays with consistently good correlations with other test methods. Applications to fibrinolysis studies have yielded global assays of thrombolytic activity, in that the assay results reflect the interactions of multiple factors associated with the effectiveness of thrombolytic therapy. Depending on the components utilized in a particular reagent formulation, one can derive information about the activity of such factors as fibrinogen, plasminogen, and related inhibitors, as well as the lytic agent being administered. Use of these assays in a clinical setting should provide a rapid, convenient alternative to conventional testing of coagulation variables and a reliable method for monitoring thrombolytic therapy. PMID:2015664

  20. Untangling the complexity of blood coagulation network: use of computational modelling in pharmacology and diagnostics.

    PubMed

    Shibeko, Alexey M; Panteleev, Mikhail A

    2016-05-01

    Blood coagulation is a complex biochemical network that plays critical roles in haemostasis (a physiological process that stops bleeding on injury) and thrombosis (pathological vessel occlusion). Both up- and down-regulation of coagulation remain a major challenge for modern medicine, with the ultimate goal to correct haemostasis without causing thrombosis and vice versa. Mathematical/computational modelling is potentially an important tool for understanding blood coagulation disorders and their treatment. It can save a huge amount of time and resources, and provide a valuable alternative or supplement when clinical studies are limited, or not ethical, or technically impossible. This article reviews contemporary state of the art in the modelling of blood coagulation for practical purposes: to reveal the molecular basis of a disease, to understand mechanisms of drug action, to predict pharmacodynamics and drug-drug interactions, to suggest potential drug targets or to improve quality of diagnostics. Different model types and designs used for this are discussed. Functional mechanisms of procoagulant bypassing agents and investigations of coagulation inhibitors were the two particularly popular applications of computational modelling that gave non-trivial results. Yet, like any other tool, modelling has its limitations, mainly determined by insufficient knowledge of the system, uncertainty and unreliability of complex models. We show how to some extent this can be overcome and discuss what can be expected from the mathematical modelling of coagulation in not-so-far future.

  1. Measurement of blood coagulation with considering RBC aggregation through a microchip-based light transmission aggregometer.

    PubMed

    Lim, Hyunjung; Nam, Jeonghun; Xue, Shubin; Shin, Sehyun

    2011-01-01

    Even though blood coagulation can be tested by various methods and techniques, the effect of RBC aggregation on blood coagulation is not fully understood. The present study monitored clot formation in a microchip-based light transmission aggregometer. Citrated blood samples with and without the addition of calcium ion solution were initially disaggregated by rotating a stirrer in the microchip. After abrupt stop of the rotating stirrer, the transmitted light intensity over time was recorded. The syllectogram (light intensity vs. time graph) manifested a rapid increase that is associated with RBC aggregation followed by a decrease that is associated with blood coagulation. The time to reach the peak point was used as a new index of coagulation time (CT) and ranged from 200 to 500 seconds in the present measurements. The CT was inversely proportional to the concentration of fibrinogen, which enhances RBC aggregation. In addition, the CT was inversely proportional to the hematocrit, which is similar to the case of the prothrombin time (PT), as measured by a commercial coagulometer. Thus, we carefully concluded that RBC aggregation should be considered in tests of blood coagulation.

  2. Rapid evaluation of fibrinogen levels using the CG02N whole blood coagulation analyzer.

    PubMed

    Hayakawa, Mineji; Gando, Satoshi; Ono, Yuichi; Mizugaki, Asumi; Katabami, Kenichi; Maekawa, Kunihiko; Miyamoto, Daisuke; Wada, Takeshi; Yanagida, Yuichiro; Sawamura, Atsushi

    2015-04-01

    Rapid evaluation of fibrinogen (Fbg) levels is essential for maintaining homeostasis in patients with massive bleeding during severe trauma and major surgery. This study evaluated the accuracy of fibrinogen levels measured by the CG02N whole blood coagulation analyzer (A&T Corporation, Kanagawa, Japan) using heparinized blood drawn for blood gas analysis (whole blood-Fbg). A total of 100 matched pairs of heparinized blood samples and citrated blood samples were simultaneously collected from patients in the intensive care unit. Whole blood-Fbg results were compared with those of citrated plasma (standard-Fbg). The whole blood coagulation analyzer measured fibrinogen levels within 2 minutes. Strong correlations between standard-Fbg and whole blood-Fbg were observed (ρ = 0.91, p < 0.001). Error grid analysis showed that 88% of the values were clinically acceptable, and 12% were in a range with possible effects on clinical decision-making; none were in a clinically dangerous range without appropriate treatment. Using a fibrinogen cutoff value of 1.5 g/L for standard-Fbg, the area under the receiver operating characteristic curve of whole blood-Fbg was 0.980 (95% confidence interval 0.951-1.000, p < 0.001). The whole blood coagulation analyzer can rapidly measure fibrinogen levels in heparinized blood and could be useful in critical care settings where excessive bleeding is a concern.

  3. Blood coagulation screening using a paper-based microfluidic lateral flow device.

    PubMed

    Li, H; Han, D; Pauletti, G M; Steckl, A J

    2014-10-21

    A simple approach to the evaluation of blood coagulation using a microfluidic paper-based lateral flow assay (LFA) device for point-of-care (POC) and self-monitoring screening is reported. The device utilizes whole blood, without the need for prior separation of plasma from red blood cells (RBC). Experiments were performed using animal (rabbit) blood treated with trisodium citrate to prevent coagulation. CaCl2 solutions of varying concentrations are added to citrated blood, producing Ca(2+) ions to re-establish the coagulation cascade and mimic different blood coagulation abilities in vitro. Blood samples are dispensed into a paper-based LFA device consisting of sample pad, analytical membrane and wicking pad. The porous nature of the cellulose membrane separates the aqueous plasma component from the large blood cells. Since the viscosity of blood changes with its coagulation ability, the distance RBCs travel in the membrane in a given time can be related to the blood clotting time. The distance of the RBC front is found to decrease linearly with increasing CaCl2 concentration, with a travel rate decreasing from 3.25 mm min(-1) for no added CaCl2 to 2.2 mm min(-1) for 500 mM solution. Compared to conventional plasma clotting analyzers, the LFA device is much simpler and it provides a significantly larger linear range of measurement. Using the red colour of RBCs as a visible marker, this approach can be utilized to produce a simple and clear indicator of whether the blood condition is within the appropriate range for the patient's condition.

  4. [Modern coagulation management reduces the transfusion rate of allogenic blood products].

    PubMed

    Weber, Christian Friedrich

    2012-06-01

    Evaluating the patient's individual bleeding history with a standardized questionnaire, using "point-of-care" - methods for coagulation analyses and providing autologous transfusion techniques are preconditions of a modern coagulation management. Therapy of coagulopathic patients should be based on structured hemotherapy algorithms. Surgical haemostasis and the maintenance of the basic conditions for haemostasis are elementary requirements for an effective therapy. In cases of diffuse bleeding, early antifibrinolytic therapy should be considered. Coagulation factor deficiencies should be corrected "goal-directed" using coagulation factor concentrates. Transfusion of fresh frozen plasma is only indicated in the clinical setting of massive transfusions. DDAVP and transfusion of platelet concentrates are options to optimize primary haemostasis. In cases of on-going bleeding, recombinant activated coagulation factor VII represents an option for "ultima-ratio" therapy.

  5. Acetaminophen and meloxicam inhibit platelet aggregation and coagulation in blood samples from humans.

    PubMed

    Martini, Angela K; Rodriguez, Cassandra M; Cap, Andrew P; Martini, Wenjun Z; Dubick, Michael A

    2014-12-01

    Acetaminophen (Ace) and meloxicam (Mel) are the two types of analgesic and antipyretic medications. This study investigated the dose responses of acetaminophen and meloxicam on platelet aggregation and coagulation function in human blood samples. Blood samples were collected from six healthy humans and processed to make platelet-adjusted (100 × 10 cells/μl) blood samples. Acetaminophen (Tylenol, Q-PAP, 100 mg/ml) was added at the doses of 0 μg/ml (control), 214 μg/ml (the standard dose, 1 ×), 4 ×, 8 ×, 10 ×, 12 ×, 16 ×, and 20 ×. Similarly, meloxicam (Metacam, 5 mg/ml) was added at doses of 0 μg/ml (control), 2.85 μg/ml (the standard dose, 1 ×), 4 ×, 8 ×, 10 ×, 12 ×, 16 ×, and 20 ×. Fifteen minutes after the addition of acetaminophen and/or meloxicam, platelet aggregation was stimulated with collagen (2 μg/ml) or arachidonic acid (0.5 mmol/l) and assessed using a Chrono-Log 700 aggregometer. Coagulation function was assessed by prothrombin time (PT), activated partial thromboplastin time (aPTT), and using Rotem thrombelastogram. A robust inhibition by acetaminophen and/or meloxicam was observed in arachidonic acid-stimulated platelet aggregation starting at 1 × dose. Collagen-stimulated platelet aggregation was inhibited by ACE starting at 1 × (78 ± 10% of control), and by meloxicam starting at 4 × (72 ± 5% of control, both P < 0.05). The inhibitions by acetaminophen and meloxicam combined were similar to those by acetaminophen or meloxicam. aPTT was prolonged by meloxicam starting at 4 ×. No changes were observed in PT or any of Rotem measurements by acetaminophen and/or meloxicam. Acetaminophen and meloxicam compromised platelet aggregation and aPTT. Further effort is warranted to characterize the effects of acetaminophen and meloxicam on bleeding in vivo.

  6. Blood coagulation protein fibrinogen promotes autoimmunity and demyelination via chemokine release and antigen presentation

    PubMed Central

    Ryu, Jae Kyu; Petersen, Mark A.; Murray, Sara G.; Baeten, Kim M.; Meyer-Franke, Anke; Chan, Justin P.; Vagena, Eirini; Bedard, Catherine; Machado, Michael R.; Coronado, Pamela E. Rios; Prod'homme, Thomas; Charo, Israel F.; Lassmann, Hans; Degen, Jay L.; Zamvil, Scott S.; Akassoglou, Katerina

    2015-01-01

    Autoimmunity and macrophage recruitment into the central nervous system (CNS) are critical determinants of neuroinflammatory diseases. However, the mechanisms that drive immunological responses targeted to the CNS remain largely unknown. Here we show that fibrinogen, a central blood coagulation protein deposited in the CNS after blood–brain barrier disruption, induces encephalitogenic adaptive immune responses and peripheral macrophage recruitment into the CNS leading to demyelination. Fibrinogen stimulates a unique transcriptional signature in CD11b+ antigen-presenting cells inducing the recruitment and local CNS activation of myelin antigen-specific Th1 cells. Fibrinogen depletion reduces Th1 cells in the multiple sclerosis model, experimental autoimmune encephalomyelitis. Major histocompatibility complex (MHC) II-dependent antigen presentation, CXCL10- and CCL2-mediated recruitment of T cells and macrophages, respectively, are required for fibrinogen-induced encephalomyelitis. Inhibition of the fibrinogen receptor CD11b/CD18 protects from all immune and neuropathologic effects. Our results show that the final product of the coagulation cascade is a key determinant of CNS autoimmunity. PMID:26353940

  7. Thrombin generation by exposure of blood to endotoxin: a simple model to study disseminated intravascular coagulation.

    PubMed

    Stief, T W

    2006-04-01

    Pathologic disseminated intravascular coagulation (PDIC) is a serious complication in sepsis. In an in-vitro system consisting of incubation of fresh citrated blood with lipopolysaccharides (LPS) or glucans and subsequent plasma recalcification plasmatic thrombin was quantified. Five hundred microliters of freshly drawn citrated blood of healthy donors were incubated with up to 800 ng/mL LPS (Escherichia coli) or up to 80 microg/mL Zymosan A (ZyA; Candida albicans) for 30 minutes at room temperature (RT). The samples were centrifuged, and 30 microL plasma were recalcified with 1 volume or less of CaCl(2) (25 micromoles Ca(2+)/mL plasma). After 0 to 12 minutes (37 degrees C), 20 microL 2.5 M arginine, pH 8.6, were added. Thirty microliters 0.9 mM HD-CHG-Ala-Arg-pNA in 2.3 M arginine were added, and the absorbance increase at 405 nm was determined. Fifty microliters plasma were also incubated with 5 microL 250 mM CaCl2 for 5, 10, or 15 minutes (37 degrees C). Fifty microliters 2.5 M arginine stops coagulation, and 50 microL 0.77 mM HD-CHG-Ala-Arg-pNA in 2.3 M arginine starts the thrombin detection. The standard was 1 IU/mL thrombin in 7% human albumin instead of plasma. Arginine was also added in the endotoxin exposure time (EET) or in the plasma coagulation reaction time (CRT). Tissue factor (TF)-antigen and soluble CD14 were determined. LPS at blood concentrations greater than 10 ng/mL or ZyA at greater than 1 microg/mL severalfold enhance thrombin generation, when the respective plasmas are recalcified. After 30 minutes EET at RT, the thrombin activity at 12 minutes CRT generated by the addition of 200 ng/mL LPS or 20 microg/mL ZyA is approximately 200 mIU/mL compared to approximately 20 mIU/mL without addition of endotoxin, or compared to about 7 mIU/mL thrombin at 0 minutes CRT. Arginine added to blood or to plasma inhibits thrombin generation; the inhibitory concentration 50% (IC 50) is approximately 15 mM plasma concentration. Endotoxin incubation of blood

  8. Detection of mild inherited disorders of blood coagulation: current options and personal recommendations.

    PubMed

    Lippi, Giuseppe; Pasalic, Leonardo; Favaloro, Emmanuel J

    2015-08-01

    Although assessment of prior personal and familial bleeding history is an important aspect of the diagnosis of bleeding disorders, patients with mild inherited bleeding disorders are sometimes clinically asymptomatic until presented with a hemostatic challenge. However, bleeding may occur after incursion of trauma or surgery, so detection of these conditions reflects an important facet of clinical and laboratory practice. Mild bleeding disorders may be detected as a result of family studies or following identification of abnormal values in first-line screening tests such as activated partial thromboplastin time, prothrombin time, fibrinogen and global platelet function screen testing, such as the platelet function analyzer. Following determination of abnormal screening tests, subsequent investigation should follow a systematic approach that targets specific diagnostic tests, and including factor assays, full platelet function assays and more extensive specialized hemostasis testing. The current report provides a personal overview on inherited disorders of blood coagulation and their detection.

  9. [Basic values of blood coagulation parameters in pigs (Sus scrofa domesticus)].

    PubMed

    Hahn, N; Popov-Cenic, S; Dorer, A

    1996-01-01

    On 23 clinical healthy pigs (2-4 months of age, body weight 13-42 kg) under ketamin-pentobarbital anaesthesia blood plasma coagulation parameters have been investigated. To obtain basic values 26 parameters were measured: number of thrombocytes, parameters of thrombelastogram and resonance-thrombogram, prothrombin time, activated partial thromboplastin time, thrombin time, reptilase time, factors I, II, V, VII, VIII, X, antithrombin III, plasminogen, alpha 1-antitrypsin, alpha 2-antiplasmin, alpha 2-macroglobulin, fibrin degradation products D and E and euglobulin lysis-time. Parameters calculated in percent should be measured against a pig plasma pool. Measurement against a human plasma pool are hardly valid in values higher than 100%. In comparison to man the results indicate modifications of fibrinogenesis and fibrinolysis in pigs.

  10. Influence of natural coagulants on isoflavones and antioxidant activity of tofu.

    PubMed

    Rekha, C R; Vijayalakshmi, G

    2010-08-01

    Tofu (instead of preparing using synthetic coagulant) was prepared using coagulants of plant origin (Citrus limonum, Garcinia indica, Tamarindus indica, Phyllanthus acidus and Passiflora edulis). Total crude protein and fat contents were highest in tofu prepared using G. indica and T. indica (72.5% dbw) compared to synthetic coagulant. Tofu prepared with natural coagulants had signifi cantly higher antioxidant activity compared to synthetic coagulant. Bioconversion of isoflavone glucosides (daidzin and genistin) into their corresponding bioactive aglycones (daidzein and genistein) was observed in tofu. The difference between glucosides and aglycones contents in soy milk was significant but there was not much difference in tofu coagulated with synthetic and natural coagulants.

  11. Activation of coagulation after administration of tumor necrosis factor to normal subjects.

    PubMed

    van der Poll, T; Büller, H R; ten Cate, H; Wortel, C H; Bauer, K A; van Deventer, S J; Hack, C E; Sauerwein, H P; Rosenberg, R D; ten Cate, J W

    1990-06-01

    Tumor necrosis factor has been implicated in the activation of blood coagulation in septicemia, a condition commonly associated with intravascular coagulation and disturbances of hemostasis. To evaluate the early dynamics and the route of the in vivo coagulative response to tumor necrosis factor, we performed a controlled study in six healthy men, monitoring the activation of the common and intrinsic pathways of coagulation with highly sensitive and specific radioimmunoassays. Recombinant human tumor necrosis factor, administered as an intravenous bolus injection (50 micrograms per square meter of body-surface area), induced an early and short-lived rise in circulating levels of the activation peptide of factor X, reaching maximal values after 30 to 45 minutes (mean +/- SEM increase after 45 minutes, 34.2 +/- 18.2 percent; tumor necrosis factor vs. saline, P = 0.015). This was followed by a gradual and prolonged increase in the plasma concentration of the prothrombin fragment F1+2, peaking after four to five hours (mean increase after five hours, 348.0 +/- 144.8 percent; tumor necrosis factor vs. saline, P less than 0.0001). These findings signify the formation of factor Xa (activated factor X) and the activation of prothrombin. Activation of the intrinsic pathway could not be detected by a series of measurements of the plasma levels of factor XII, prekallikrein, factor XIIa-C1 inhibitor complexes, kallikrein-C1 inhibitor complexes, and the activation peptide of factor IX. The delay between the maximal activation of factor X and that of prothrombin amounted to several hours, indicating that neutralization of factor Xa activity was slow. We conclude that a single injection of tumor necrosis factor elicits a rapid and sustained activation of the common pathway of coagulation, probably induced through the extrinsic route. Our results suggest that tumor necrosis factor could play an important part in the early activation of the hemostatic mechanism in septicemia.

  12. Coagulation activation in sickle cell trait: an exploratory study.

    PubMed

    Amin, Chirag; Adam, Soheir; Mooberry, Micah J; Kutlar, Abdullah; Kutlar, Ferdane; Esserman, Denise; Brittain, Julia E; Ataga, Kenneth I; Chang, Jen-Yea; Wolberg, Alisa S; Key, Nigel S

    2015-11-01

    Recent epidemiologic data suggest that sickle cell trait (HbAS; AS) is a risk factor for venous thromboembolism. We conducted an exploratory study of healthy subjects with AS under baseline conditions to determine whether a chronic basal hyperactivation of coagulation exists, and if so, what mechanism(s) contribute to this state. Eighteen healthy AS individuals were compared to 22 African-American controls with a normal haemoglobin profile (HbAA; AA) and 17 patients with sickle cell disease (HbSS; SS). Plasma thrombin-antithrombin complexes and D-dimer levels were elevated in AS relative to AA patients (P = 0·0385 and P = 0·017, respectively), and as expected, were much higher in SSversusAA (P < 0·0001 for both). Thrombin generation in platelet poor plasma was indistinguishable between AA and AS subjects, whereas a paradoxical decrease in endogenous thrombin potential was observed in SS (P ≤ 0·0001). Whole blood tissue factor was elevated in SS compared to AA (P = 0·005), but did not differ between AA and AS. Plasma microparticle tissue factor activity was non-significantly elevated in AS (P = 0·051), but was clearly elevated in SS patients (P = 0·004) when compared to AA controls. Further studies in larger cohorts of subjects with sickle cell trait are needed to confirm the results of this preliminary investigation.

  13. Nanoparticles and the blood coagulation system. Part I: benefits of nanotechnology.

    PubMed

    Ilinskaya, Anna N; Dobrovolskaia, Marina A

    2013-05-01

    Nanotechnology is proven to provide certain benefits in drug delivery by improving solubility, increasing uptake to target sites and changing pharmacokinetics profiles of traditional drugs. Since properties of many materials change tremendously at the nanoscale levels, nanotechnology is also being explored in various industrial applications. As such, nanoparticles are rapidly entering various areas of industry, biology and medicine. The benefits of using nanotechnology for industrial and biomedical applications are often tempered by concerns about the safety of these new materials. One such area of concern includes their effect on the immune system. While nanoparticle interactions with various constituents of the immune system have been reviewed before, little attention was given to nanoparticle effects on the blood coagulation system. Nanoparticle interface with the blood coagulation system may lead to either benefits to the host or adverse reactions. This article reviews recent advances in our understanding of nanoparticle interactions with plasma coagulation factors, platelets, endothelial cells and leukocytes. Part I is focused on desirable interactions between nanoparticles and the coagulation system, and discusses benefits of using nanotechnology to intervene in coagulation disorders. Undesirable interactions posing safety concerns are covered in part II, which will be published in the June issue of Nanomedicine.

  14. Interleukin 12 induces activation of fibrinolysis and coagulation in humans.

    PubMed

    Portielje, J E; Kruit, W H; Eerenberg, A J; Schuler, M; Sparreboom, A; Lamers, C H; Bolhuis, R L; Stoter, G; Huber, C; Hack, C

    2001-02-01

    Interleukin 12 (IL-12) has potential efficacy in malignant, infectious and allergic diseases. Its side-effects include activation of coagulation and fibrinolysis, as documented in chimpanzees. We assessed the coagulative and fibrinolytic response in 18 patients with renal cell carcinoma after subcutaneous injection of 0.5 microg/kg recombinant human IL-12. IL-12 induced a fibrinolytic response in 17 patients (94%): plasmin-alpha2-anti-plasmin complexes (PAPc) increased from 11.8 +/- 6.6 nmol/l (mean +/- SD) to a maximum of 18.8 +/- 7.4 nmol/l at 72 h. Baseline levels of tissue plasminogen activator (tPA) and plasminogen-activator inhibitor-I (PAI) were elevated in eight and 14 patients respectively. tPA increased from 12.6 +/- 5.2 ng/ml to a maximum of 19.0 +/- 6.7 ng/ml at 72 h. PAI decreased from 111 +/- 69 ng/ml to a minimum of 65 +/- 53 ng/ml at 8 h, thereafter remaining below baseline. Elevation of PAPc correlated with elevation of tPA and reduction of PAI. A coagulative response occurred in nine patients (50%): thrombin-anti-thrombin III complexes increased from 29 +/- 53 ng/ml to a maximum of 460 +/- 322 ng/ml at 12 h. Patients with and without a coagulative response had similar levels of recombinant human IL-12, interferon-gamma or tumour necrosis factor-alpha. We conclude that IL-12 can activate both fibrinolysis and coagulation in a significant proportion of patients with cancer. The time-frame and sequence of these activation processes differ from those known for other cytokines.

  15. [Coagulation hemostasis and fibrinolytic potential of blood in conditions of chronic stress and terahertz therapy].

    PubMed

    Kirichuk, V F; Tsymbal, A A; Antipova, O N; Tupikin, V D; Maĭborodin, A V; Krenitskiĭ, A P; Betskiĭ, O V

    2007-01-01

    The effects of electromagnetic rays of maximum high frequencies of radiation molecular spectrum and absorption of nitrogen oxide 150, 176-150, 664 GHz on blood coagulation properties of white laboratory rats subjected to chronic immobilization stress have been studied. It is shown that preventive course of electromagnetic irradiation with terahertz range at the frequencies of molecular spectrum of radiation and absorption of nitrogen oxide 150, 176-150, 664 GHz warns about development of stress disturbances of coagulation component of the hemostasis system and fibrinolysis in animals. PMID:17465273

  16. Staphylococcal superantigen-like protein 10 (SSL10) inhibits blood coagulation by binding to prothrombin and factor Xa via their γ-carboxyglutamic acid (Gla) domain.

    PubMed

    Itoh, Saotomo; Yokoyama, Ryosuke; Kamoshida, Go; Fujiwara, Toshinobu; Okada, Hiromi; Takii, Takemasa; Tsuji, Tsutomu; Fujii, Satoshi; Hashizume, Hideki; Onozaki, Kikuo

    2013-07-26

    The staphylococcal superantigen-like protein (SSL) family is composed of 14 exoproteins sharing structural similarity with superantigens but no superantigenic activity. Target proteins of four SSLs have been identified to be involved in host immune responses. However, the counterparts of other SSLs have been functionally uncharacterized. In this study, we have identified porcine plasma prothrombin as SSL10-binding protein by affinity purification using SSL10-conjugated Sepharose. The resin recovered the prodomain of prothrombin (fragment 1 + 2) as well as factor Xa in pull-down analysis. The equilibrium dissociation constant between SSL10 and prothrombin was 1.36 × 10(-7) M in surface plasmon resonance analysis. On the other hand, the resin failed to recover γ-carboxyglutamic acid (Gla) domain-less coagulation factors and prothrombin from warfarin-treated mice, suggesting that the Gla domain of the coagulation factors is essential for the interaction. SSL10 prolonged plasma clotting induced by the addition of Ca(2+) and factor Xa. SSL10 did not affect the protease activity of thrombin but inhibited the generation of thrombin activity in recalcified plasma. S. aureus produces coagulase that non-enzymatically activates prothrombin. SSL10 attenuated clotting induced by coagulase, but the inhibitory effect was weaker than that on physiological clotting, and SSL10 did not inhibit protease activity of staphylothrombin, the complex of prothrombin with coagulase. These results indicate that SSL10 inhibits blood coagulation by interfering with activation of coagulation cascade via binding to the Gla domain of coagulation factor but not by directly inhibiting thrombin activity. This is the first finding that the bacterial protein inhibits blood coagulation via targeting the Gla domain of coagulation factors.

  17. In vitro carboxylation of a blood coagulation factor IX precursor produced by recombinant-DNA technology.

    PubMed

    Soute, B A; Balland, A; Faure, T; de la Salle, H; Vermeer, C

    1989-04-25

    Blood coagulation factor IX (Christmas factor) is a plasma protein which is required for normal haemostasis. A functional deficiency of factor IX results in haemophilia B, a bleeding disorder which is generally treated by infusions of factor IX concentrates prepared from pooled human plasma. The use of human blood products is connected with the risk of transmitting viral agents responsible for diseases such as hepatitis B and AIDS. Recombinant DNA techniques may provide the means to produce the required proteins without exposing the patients to these risks and at lower costs. One of the problems which has to be overcome before recombinant factor IX can be used for therapeutical purposes is related to the vitamin K-dependent carboxylation of its 12 NH2-terminal glutamate residues. In cell cultures this carboxylation, which is required to render the protein its procoagulant activity, is far from complete, especially at high expression levels. In this paper we describe the in vitro carboxylation of non and/or partly carboxylated recombinant factor IX produced by transformed Chinese hamster ovary cells. The identity of the newly formed Gla residues was verified and it could be demonstrated that all carboxyl groups had been incorporated into the recombinant factor IX.

  18. Inflammation-associated activation of coagulation and immune regulation by the protein C pathway.

    PubMed

    Weiler, Hartmut

    2014-05-01

    The inflammation-induced activation of the protein C pathway provides negative feedback inhibition of coagulation and exerts coagulation-independent anti-inflammatory and cytoprotective effects. The balance between these activities of aPC modulates the outcome of diverse inflammatory diseases such as encephalitis, diabetes, and sepsis; and is affected by naturally occurring aPC-resistance of coagulation factor V Leiden.

  19. Quantification of sphingosine 1-phosphate by validated LC-MS/MS method revealing strong correlation with apolipoprotein M in plasma but not in serum due to platelet activation during blood coagulation.

    PubMed

    Frej, Cecilia; Andersson, Anders; Larsson, Benny; Guo, Li Jun; Norström, Eva; Happonen, Kaisa E; Dahlbäck, Björn

    2015-11-01

    Sphingosine 1-phosphate (S1P) is a signalling sphingolipid affecting multiple cellular functions of vascular and immune systems. It circulates at submicromolar levels bound to HDL-associated apolipoprotein M (apoM) or to albumin. S1P in blood is mainly produced by platelets and erythrocytes, making blood sampling for S1P quantification delicate. Standardisation of sampling is thereby of great importance to obtain robust data. By optimising and characterising the extraction procedure and the LC-MS/MS analysis, we have developed and validated a highly specific and sensitive method for S1P quantification. Blood was collected from healthy individuals (n = 15) to evaluate the effects of differential blood sampling on S1P levels. To evaluate correlation between S1P and apoM in different types of plasma and serum, apoM was measured by ELISA. The method showed good accuracy and precision in the range of 0.011 to 0.9 μM with less than 0.07 % carryover. We found that the methanol precipitation used to extract S1P co-extracted apoM and several other HDL-proteins from plasma. The platelet-associated S1P was released during coagulation, thus increasing the S1P concentration to double in serum as compared to that in plasma. Gel filtration chromatography revealed that the platelet-released S1P was mainly bound to albumin. This explains why the strong correlation between S1P and apoM levels in plasma is lost upon the clotting process and hence not observed in serum. We have developed, characterised and validated an efficient, highly sensitive and specific method for the quantification of S1P in biological material.

  20. Coagulation tests on capillary blood. A screening procedure for use in small children.

    PubMed

    DORMANDY, K M; HARDISTY, R M

    1961-09-01

    A method of investigating the coagulation mechanism is described.Results obtained by this procedure are compared with those of tests carried out on venous blood obtained simultaneously from normal subjects and patients with a variety of clotting defects. Good correlation was found between the results of P and P tests on venous and capillary blood, and also between thromboplastin screening tests on capillary blood and antihaemophilic and Christmas factor levels. The methods described have proved reliable as a pre-operative screening procedure in routine use over a period of nearly two years.

  1. Effects of plateletpheresis on blood coagulation parameters in healthy donors at National Blood Centre, Kuala Lumpur, Malaysia.

    PubMed

    Siti Nadiah, A K; Nor Asiah, M; Nur Syimah, A T; Normi, M; Anza, E; Aini, A Nor; Mohd Zahari, T H; Shahnaz, M; Faraizah, A K; Faisal, M A

    2013-12-01

    Plateletpheresis is a method used to remove platelet from the body either from random volunteer donors, patient's family members or HLA matched donors. A cross sectional study was carried out on 59 plateletpheresis donors aged between 18 and 55 years at National Blood Center (NBC), Kuala Lumpur. We compared the blood parameters before and after plateletpheresis and we found that the platelet count, FVIII, fibrinogen and thrombophilia markers anti-thrombin (AT), protein C and protein S were significantly reduced (p<0.05) with prolonged PT and APTT. There were significant changes in blood coagulation parameters but it is within acceptable range.

  2. Coagulant and anticoagulant activities of Bothrops lanceolatus (Fer de lance) venom.

    PubMed

    Lôbo de Araújo, A; Kamiguti, A; Bon, C

    2001-01-01

    Bothrops lanceolatus venom contains caseinolytic, phospholipase, esterase and haemorrhagic activities. We have investigated the coagulant and anticoagulant actions of B. lanceolatus venom on human citrated plasma and on purified plasma components. Although B. lanceolatus venom up to 50 microg/ml was unable to clot citrated plasma, at concentrations > or = 5 microg/ml the venom dose-dependently clotted purified human fibrinogen, indicating the presence of a thrombin-like enzyme. Human plasma (final concentration > or = 12.5%) dose-dependently inhibited the venom-induced fibrinogen clotting. This finding suggested that endogenous plasma protease inhibitors can affect the venom's action on fibrinogen. To investigate this possibility, B. lanceolatus venom was incubated with different plasma protease inhibitors and the activity on fibrinogen tested. alpha(2)-Macroglobulin and alpha(1)-antitrypsin did not interfere with the coagulant activity of the venom whereas the antithrombin-III/heparin complex partially inhibited this activity. A non-toxic, acidic phospholipase A(2) purified from B. lanceolatus venom prolonged the activated partial thromboplastin time in human plasma from 39.7+/-0.5 s (control with saline) to 60.2+/-0.9 s with 50 microg of PLA(2) (p<0.001), suggesting an anticoagulant activity associated with this enzyme. This anticoagulant activity may account for some of the effects of the venom on blood coagulation. PMID:10978756

  3. Contribution of a portable air plasma torch to rapid blood coagulation as a method of preventing bleeding

    NASA Astrophysics Data System (ADS)

    Kuo, S. P.; Tarasenko, O.; Chang, J.; Popovic, S.; Chen, C. Y.; Fan, H. W.; Scott, A.; Lahiani, M.; Alusta, P.; Drake, J. D.; Nikolic, M.

    2009-11-01

    The effectiveness and mechanism of a low temperature air plasma torch in clotting blood are explored. Both blood droplets and smeared blood samples were used in the tests. The treated droplet samples reveal how blood clotting depends on the distance at which the torch operated, and for how long the droplets have been exposed to the torch. Microscopy and cell count of smeared blood samples shed light on dependencies of erythrocyte and platelet counts on torch distance and exposure time. With an increase of torch distance, the platelet count of treated blood samples increases but is less than that of the control. The flux of reactive atomic oxygen (RAO) and the degree of blood clotting decreased. With an increase of exposure time, platelet count of treated samples decreased, while the degree of clot increased. The correlation among these dependencies and published data support a blood clotting mechanism that RAO as well as other likely reactive oxygen species generated by the plasma torch activate erythrocyte-platelets interactions and induces blood coagulation.

  4. Na+ site in blood coagulation factor IXa: effect on catalysis and factor VIIIa binding.

    PubMed

    Schmidt, Amy E; Stewart, Jonathan E; Mathur, Akash; Krishnaswamy, Sriram; Bajaj, S Paul

    2005-07-01

    During blood coagulation, factor IXa (FIXa) activates factor X (FX) requiring Ca2+, phospholipid, and factor VIIIa (FVIIIa). The serine protease domain of FIXa contains a Ca2+ site and is predicted to contain a Na+ site. Comparative homology analysis revealed that Na+ in FIXa coordinates to the carbonyl groups of residues 184A, 185, 221A, and 224 (chymotrypsin numbering). Kinetic data obtained at several concentrations of Na+ and Ca2+ with increasing concentrations of a synthetic substrate (CH3-SO2-d-Leu-Gly-Arg-p-nitroanilide) were fit globally, assuming rapid equilibrium conditions. Occupancy by Na+ increased the affinity of FIXa for the synthetic substrate, whereas occupancy by Ca2+ decreased this affinity but increased k(cat) dramatically. Thus, Na+-FIXa-Ca2+ is catalytically more active than free FIXa. FIXa(Y225P), a Na+ site mutant, was severely impaired in Na+ potentiation of its catalytic activity and in binding to p-aminobenzamidine (S1 site probe) validating that substrate binding in FIXa is linked positively to Na+ binding. Moreover, the rate of carbamylation of NH2 of Val16, which forms a salt-bridge with Asp194 in serine proteases, was faster for FIXa(Y225P) and addition of Ca2+ overcame this impairment only partially. Further studies were aimed at delineating the role of the FIXa Na+ site in macromolecular catalysis. In the presence of Ca2+ and phospholipid, with or without saturating FVIIIa, FIXa(Y225P) activated FX with similar K(m) but threefold reduced k(cat). Further, interaction of FVIIIa:FIXa(Y225P) was impaired fourfold. Our previous data revealed that Ca2+ binding to the protease domain increases the affinity of FIXa for FVIIIa approximately 15-fold. The present data indicate that occupancy of the Na+ site further increases the affinity of FIXa for FVIIIa fourfold and k(cat) threefold. Thus, in the presence of Ca2+, phospholipid, and FVIIIa, binding of Na+ to FIXa increases its biologic activity by approximately 12-fold, implicating its role

  5. Vascular repair utilising immobilised heparin conjugate for protection against early activation of inflammation and coagulation.

    PubMed

    Nordling, Sofia; Hong, Jaan; Fromell, Karin; Edin, Fredrik; Brännström, Johan; Larsson, Rolf; Nilsson, Bo; Magnusson, Peetra U

    2015-06-01

    Ischaemia-reperfusion injury (IRI) poses a major challenge in many thrombotic conditions and in whole organ transplantation. Activation of the endothelial cells and shedding of the protective vascular glycocalyx during IRI increase the risk of innate immune activation, cell infiltration and severe thrombus formation, promoting damage to the tissue. Here, we present a novel one-step strategy to protect the vasculature by immobilisation of a unique multi-arm heparin conjugate to the endothelium. Applying a new in vitro blood endothelial cell chamber model, the heparin conjugate was found to bind not only to primary human endothelial cells but also directly to the collagen to which the cells adhered. Incubation of hypoxic endothelial cells with freshly drawn human blood in the blood chambers elicited coagulation activation reflected by thrombin anti-thrombin formation and binding of platelets and neutrophils. Immobilisation of the heparin conjugate to the hypoxic endothelial cells created a protective coating, leading to a significant reduction of the recruitment of blood cells and coagulation activation compared to untreated hypoxic endothelial cells. This novel approach of immobilising multi-arm heparin conjugates on the endothelial cells and collagen of the basement membrane ensures to protect the endothelium against IRI in thrombotic disorders and in transplantation.

  6. Dynamics of spatially nonuniform patterning in the model of blood coagulation

    NASA Astrophysics Data System (ADS)

    Zarnitsina, V. I.; Ataullakhanov, F. I.; Lobanov, A. I.; Morozova, O. L.

    2001-03-01

    We propose a reaction-diffusion model that describes in detail the cascade of molecular events during blood coagulation. In a reduced form, this model contains three equations in three variables, two of which are self-accelerated. One of these variables, an activator, behaves in a threshold manner. An inhibitor is also produced autocatalytically, but there is no inhibitor threshold, because it is generated only in the presence of the activator. All model variables are set to have equal diffusion coefficients. The model has a stable stationary trivial state, which is spatially uniform and an excitation threshold. A pulse of excitation runs from the point where the excitation threshold has been exceeded. The regime of its propagation depends on the model parameters. In a one-dimensional problem, the pulse either stops running at a certain distance from the excitation point, or it reaches the boundaries as an autowave. However, there is a parameter range where the pulse does not disappear after stopping and exists stationarily. The resulting steady-state profiles of the model variables are symmetrical relative to the center of the structure formed.

  7. Optical coherence tomography to investigate optical properties of blood during coagulation

    NASA Astrophysics Data System (ADS)

    Xu, Xiangqun; Lin, Jia; Fu, Feifei

    2011-09-01

    This study investigates the optical properties of human blood during the coagulation process under statics using optical coherence tomography (OCT). OCT signal slope (OCTSS) and 1/e light penetration depth (d1/e) were obtained from the profiles of reflectance versus depth. Results showed that both OCTSS and d1/e were able to sensitively differentiate various stages of blood properties during coagulating. After 1 h clotting, OCTSS decreased by 47.0%, 15.0%, 13.7%, and 8.5% and d1/e increased by 34.7%, 29.4%, 24.3%, and 22.9% for the blood samples at HCT of 25%, 35%, 45%, and 55%, respectively. The slope of d1/e versus time (Sr, ×10-4 mm/s), associated with clot formation rate decreased from 6.0+/-0.3, 3.7+/-0.5 to 2.3+/-0.4 with the increasing of HCT from 35%, 45%, to 55%. The clotting time (tc) from the d1/e evolution curves was estimated to be 1969+/-92 s, 375+/-12 s, 455+/-11 s, and 865+/-47 s for the blood of 25%, 35%, 45%, and 55%. This study demonstrates that the parameters (tc and Sr) from the variations in d1/e had better sensitivity and smaller standard deviation. Furthermore, blood hematocrit affecting backscattering properties of blood during coagulation was capable of being discerned by OCT parameters. It is concluded that OCT is a potential technique to quantify and follow the liquid-gel transition of blood during clotting.

  8. Effects of Hemoglobin-Based Oxygen Carriers on Blood Coagulation

    PubMed Central

    Roghani, Kimia; Holtby, Randall J.; Jahr, Jonathan S.

    2014-01-01

    For many decades, Hemoglobin-based oxygen carriers (HBOCs) have been central in the development of resuscitation agents that might provide oxygen delivery in addition to simple volume expansion. Since 80% of the world population lives in areas where fresh blood products are not available, the application of these new solutions may prove to be highly beneficial (Kim and Greenburg 2006). Many improvements have been made to earlier generation HBOCs, but various concerns still remain, including coagulopathy, nitric oxide scavenging, platelet interference and decreased calcium concentration secondary to volume expansion (Jahr et al. 2013). This review will summarize the current challenges faced in developing HBOCs that may be used clinically, in order to guide future research efforts in the field. PMID:25514567

  9. Alterations in Blood Coagulation and Viscosity Among Young Male Cigarette Smokers of Al-Jouf Region in Saudi Arabia.

    PubMed

    Almarshad, Hassan A; Hassan, Fathelrahman M

    2016-05-01

    Hemorheology, a measure of rheological properties of blood, is often correlated with cerebral blood flow and cardiac output; an increased blood viscosity may increase the risk of thrombosis or thromboembolic events. Previous studies have reported a large variation in hemorheological properties of blood among smokers. This prompted us to conduct coagulation experiments to evaluate the effect of cigarette smoking on hematological parameters, like cell counts, and coagulation parameters among young males in Al-Jouf region, Saudi Arabia. The hematological and coagulation parameters were used to relate the changes in viscosity and coagulation to smoking. A total of 321 male participants (126 nonsmokers and 195 smokers) were enrolled into the study as randomized sample. Complete blood count was measured by hematology analyzer, and coagulation tests were performed by coagulation analyzer. Thettest analysis was performed to compare the relationships of variables between the 2 groups. The results confirmed that smoking alters some hematology parameters leading to significant deterioration in blood flow properties. Smoking also increased the hematocrit (HCT), whole blood viscosity (WBV), and plasma viscosity (PV) but decreased the international normalized ratio (INR). The decrease in INR was found to be associated with the increase in WBV, PV, and HCT. Further investigations are necessary to assess the reversibility of such changes in cessation of smoking or other elements of influence.

  10. Protein corona changes mediated by surface modification of amorphous silica nanoparticles suppress acute toxicity and activation of intrinsic coagulation cascade in mice

    NASA Astrophysics Data System (ADS)

    Yoshida, Tokuyuki; Yoshioka, Yasuo; Morishita, Yuki; Aoyama, Michihiko; Tochigi, Saeko; Hirai, Toshiro; Tanaka, Kota; Nagano, Kazuya; Kamada, Haruhiko; Tsunoda, Shin-ichi; Nabeshi, Hiromi; Yoshikawa, Tomoaki; Higashisaka, Kazuma; Tsutsumi, Yasuo

    2015-06-01

    Recently, nanomaterial-mediated biological effects have been shown to be governed by the interaction of nanomaterials with some kinds of proteins in biological fluids, and the physical characteristics of the nanomaterials determine the extent and type of their interactions with proteins. Here, we examined the relationships between the surface properties of amorphous silica nanoparticles with diameters of 70 nm (nSP70), their interactions with some proteins in biological fluids, and their toxicity in mice after intravenous administration. The surface modification of nSP70 with amino groups (nSP70-N) prevented acute lethality and abnormal activation of the coagulation cascade found in the nSP70-treated group of mice. Since our previous study showed that coagulation factor XII played a role in the nSP70-mediated abnormal activation of the coagulation cascade, we examined the interaction of nSP70 and nSP70-N with coagulation factor XII. Coagulation factor XII bonded to the surface of nSP70 to a greater extent than that observed for nSP70-N, and consequently more activation of coagulation factor XII was observed for nSP70 than for nSP70-N. Collectively, our results suggest that controlling the interaction of nSP70 with blood coagulation factor XII by modifying the surface properties would help to inhibit the nSP70-mediated abnormal activation of the blood coagulation cascade.

  11. Coagulation Factor Concentrates Fail to Restore Alterations in Fibrin Formation Caused by Rivaroxaban or Dabigatran in Studies With Flowing Blood From Treated Healthy Volunteers.

    PubMed

    Arellano-Rodrigo, Eduardo; Lopez-Vilchez, Irene; Galan, Ana M; Molina, Patricia; Reverter, Joan Carles; Carné, Xavier; Villalta, Jaume; Tassies, Dolors; Lozano, Miguel; Díaz-Ricart, Maribel; Escolar, Gines

    2015-10-01

    We evaluated the hemostatic alterations in blood from healthy individuals treated for 5 days with direct oral anticoagulants (DOACs) rivaroxaban (20 mg/d) or dabigatran (150 mg/12 h) in a single-blind clinical trial with crossover assignment (NCT01478282). We assessed the potential of prothrombin complex concentrates, activated prothrombin complex concentrates, or recombinant activated factor VII, when added ex vivo, to reverse the alterations caused by these DOACs. Blood was drawn at maximum plasma concentration after the last dose of each DOAC, and modifications in coagulation biomarkers were evaluated using a series of tests performed under steady conditions including routine coagulation, thrombin generation, and thromboelastometry assays. Additional studies in standardized flow devices were applied to evaluate alterations on platelet deposition and fibrin formation on damaged vascular surfaces exposed to flowing blood. Both DOACs caused important modifications of all coagulation biomarkers and significantly reduced fibrin formation in flow studies. Alterations in biomarkers observed in steady laboratory tests were normalized and occasionally overcompensated by procoagulant strategies. In contrast, reductions in fibrin formation observed in studies with flowing blood were improved, although never completely restored to baseline levels. Effects of dabigatran in flow studies appeared more resistant to reversal strategies than those of rivaroxaban. Inconsistencies between results of coagulation studies in steady or flowing assays not only raise concerns about the adequacy of the earlier tests to predict the restoration of the coagulopathy induced by DOACs but also suggest limitations of nonspecific procoagulant strategies to control severe coagulopathy in patients inadvertently overexposed these agents.

  12. Coagulation Factor Concentrates Fail to Restore Alterations in Fibrin Formation Caused by Rivaroxaban or Dabigatran in Studies With Flowing Blood From Treated Healthy Volunteers.

    PubMed

    Arellano-Rodrigo, Eduardo; Lopez-Vilchez, Irene; Galan, Ana M; Molina, Patricia; Reverter, Joan Carles; Carné, Xavier; Villalta, Jaume; Tassies, Dolors; Lozano, Miguel; Díaz-Ricart, Maribel; Escolar, Gines

    2015-10-01

    We evaluated the hemostatic alterations in blood from healthy individuals treated for 5 days with direct oral anticoagulants (DOACs) rivaroxaban (20 mg/d) or dabigatran (150 mg/12 h) in a single-blind clinical trial with crossover assignment (NCT01478282). We assessed the potential of prothrombin complex concentrates, activated prothrombin complex concentrates, or recombinant activated factor VII, when added ex vivo, to reverse the alterations caused by these DOACs. Blood was drawn at maximum plasma concentration after the last dose of each DOAC, and modifications in coagulation biomarkers were evaluated using a series of tests performed under steady conditions including routine coagulation, thrombin generation, and thromboelastometry assays. Additional studies in standardized flow devices were applied to evaluate alterations on platelet deposition and fibrin formation on damaged vascular surfaces exposed to flowing blood. Both DOACs caused important modifications of all coagulation biomarkers and significantly reduced fibrin formation in flow studies. Alterations in biomarkers observed in steady laboratory tests were normalized and occasionally overcompensated by procoagulant strategies. In contrast, reductions in fibrin formation observed in studies with flowing blood were improved, although never completely restored to baseline levels. Effects of dabigatran in flow studies appeared more resistant to reversal strategies than those of rivaroxaban. Inconsistencies between results of coagulation studies in steady or flowing assays not only raise concerns about the adequacy of the earlier tests to predict the restoration of the coagulopathy induced by DOACs but also suggest limitations of nonspecific procoagulant strategies to control severe coagulopathy in patients inadvertently overexposed these agents. PMID:26364029

  13. Time-course effects of intravenously administrated silica nanoparticles on blood coagulation and endothelial function in rats.

    PubMed

    Liu, Xin; Sun, Jiao

    2013-01-01

    Among the most used inorganic nanomaterials, silica nanoparticles (NPs) have been considered as either drug carriers or contrast agents. Though the distribution of silica NPs via the circulation appears highly probable, to date, there are few studies investigating the vascular effects of silica NPs in vivo. This study was designed specifically to investigate whether silica NPs with intravenous injection could lead to blood coagulation disorder and endothelium dysfunction in vivo. The time-course effect of silica NPs on blood coagulation, oxidative stress and the expression of soluble E-selectin (sE-selectin) and tissue factor (TF) in the plasma of Sprague Dawley (SD) rats were presented. Our data showed that a shortened prothrombin time (PT) was observed on 1 day after exposure to silica NPs, while activated partial thromboplastin time (APTT) was not affected at any time-points. After the post-injection respectively, the levels of fibrinogen (Fbg) were increased by silica NPs from 1 day to 3 days, and returned to normal value on the 7th day. Meanwhile, a sustained increase in the levels of TF and sE-selectin was elicited by silica NPs during 7 days after the injection. In addition, after 7 days of intravenously injection of silica NPs, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in the plasma of SD rats were decreased significantly, whereas the level of malondialdehyde (MDA) was not changed obviously. In conclusion, intravenously administration of silica NPs could shorten PT but not APTT increase TF and sE-selectin release and reduce GSH-px and SOD activity in the plasma of SD rats, indicating exposure to silica NPs could early activate coagulation cascade via the extrinsic pathway, and may be dependent on endothelium dysfunction and oxidative stress.

  14. Measurement of factor v activity in human plasma using a microplate coagulation assay.

    PubMed

    Tilley, Derek; Levit, Irina; Samis, John A

    2012-09-09

    In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin which forms an insoluble clot that stops hemorrhage. Factor V (FV) in its activated form, FVa, is a critical cofactor for the protease FXa and accelerator of thrombin generation during fibrin clot formation as part of prothrombinase (1, 2). Manual FV assays have been described (3, 4), but they are time consuming and subjective. Automated FV assays have been reported (5-7), but the analyzer and reagents are expensive and generally provide only the clot time, not the rate and extent of fibrin formation. The microplate platform is preferred for measuring enzyme-catalyzed events because of convenience, time, cost, small volume, continuous monitoring, and high-throughput (8, 9). Microplate assays have been reported for clot lysis (10), platelet aggregation (11), and coagulation Factors (12), but not for FV activity in human plasma. The goal of the method was to develop a microplate assay that measures FV activity during fibrin formation in human plasma. This novel microplate method outlines a simple, inexpensive, and rapid assay of FV activity in human plasma. The assay utilizes a kinetic microplate reader to monitor the absorbance change at 405 nm during fibrin formation in human plasma (Figure 1) (13). The assay accurately measures the time, initial rate, and extent of fibrin clot formation. It requires only μl quantities of plasma, is complete in 6 min, has high-throughput, is sensitive to 24-80 pM FV, and measures the amount of unintentionally activated (1-stage activity) and thrombin-activated FV (2-stage activity) to obtain a complete assessment of its total functional activity (2-stage activity - 1-stage activity). Disseminated intravascular coagulation (DIC) is an acquired coagulopathy that most often develops from pre-existing infections (14). DIC is associated with a poor prognosis and increases mortality

  15. Effects on fibrinogen, fibrin, and blood coagulation of proteolytic extracts from fruits of Pseudananas macrodontes, Bromelia balansae, and B. hieronymi (Bromeliaceae) in comparison with bromelain.

    PubMed

    Errasti, María E; Prospitti, Anabela; Viana, Carolina A; Gonzalez, Mariana M; Ramos, Márcio V; Rotelli, Alejandra E; Caffini, Néstor O

    2016-06-01

    Extracts rich in cysteine proteases obtained from fruits of Pseudananas macrodontes (Pm), Bromelia balansae (Bb), and B. hieronymi (Bh) have previously shown an anti-inflammatory effect on animal models. Given the close relationship between hemostasis and inflammation, it is attractive to investigate therapeutic agents capable of modulating both systems. The aim of this work was to study the effect of Pm, Bb, and Bh on fibrin(ogen) and blood coagulation compared with stem bromelain (Bro). Action on fibrinogen was electrophoretically and spectrophotometrically evaluated, fibrinolytic activity was measured both electrophoretically and by the fibrin plate assay, and the effect on blood coagulation was studied by conventional coagulation tests (PT and APPT). All extracts showed the same proteolytic preference for fibrinogen subunits, that is Aα > Bβ, whereas γ was partially hydrolyzed by 100-fold concentration increase. Unlike Bro, cysteine proteases of Pm, Bb, and Bh increased absorbance at 540 nm of fibrinogen solution, suggesting thrombin-like activity, which was time-dependent and reached maximum values at lower concentration. All extracts showed the same proteolytic preference for fibrin subunits; however Pm, Bb, and Bh showed lower fibrinolytic activity than Bro at the assayed concentrations. Although Bb acted only as anticoagulant, Pm, Bh, and unexpectedly Bro showed dual action on blood coagulation: at low concentration showed procoagulant effect and at high concentration anticoagulant effect. Results reveal new plant species as potential sources of pharmacological agents for the treatment of a wide range of hemostatic disorders as well as to wound healing.

  16. Haem-assisted dityrosine-cross-linking of fibrinogen under non-thermal plasma exposure: one important mechanism of facilitated blood coagulation

    PubMed Central

    Ke, Zhigang; Huang, Qing

    2016-01-01

    Although blood coagulation facilitated by non-thermal plasma has been reported several years ago, the insight to the involved mechanisms is still rather limited. In this work, we report our discovery of a new mechanism for the haem-promoted blood-coagulation caused by non-thermal plasma treatment. The reason for the haem role is due to that its oxidized form, namely, hematin, can promote the dityrosine cross-linking of fibrinogen, the most important coagulation protein, to form a membrane-like layer on the surface of the treated blood with plasma exposure. Both haem and non-thermal-plasma generated hydrogen peroxide are requisite for the cross-linking process. We confirmed that fibrinogen can coordinate with the haem iron to form a protein-haem complex which shows pseudo-peroxidase activity, and in the presence of hydrogen peroxide, the complex can induce the dityrosine formation between fibrinogen molecules, leading to the fibrin network necessary for the blood coagulation. Understanding of such an underlying mechanism can be useful to guide more efficient application of non-thermal plasma in the management of hemostasis, thrombosis and etc. PMID:27229173

  17. Effects of dimethylformamide (DMF) on coagulation and platelet activity

    SciTech Connect

    Imbriani, M.; Ghittori, S.; Prestinoni, A.; Longoni, P.; Cascone, G.; Gamba, G.

    1986-03-01

    The effects of dimethylformamide (DMF) on hemostatic functions, especially on platelet activity, were examined both in vitro and in vivo in 15 workers exposed to DMF (27 mg/m3, median value). Twenty-eight control subjects who were not exposed to DMF, but comparable for age, anthropometric data, and smoking habits, were also studied. Workers exposed to DMF showed a decrease in the number of platelets and had longer coagulation times, probably due to a change caused by DMF on the membrane receptor of platelets and on the phospholipid components of the clotting system.

  18. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting... pulmonary embolism by measuring the coagulation time of whole blood. (b) Classification. Class...

  19. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting... pulmonary embolism by measuring the coagulation time of whole blood. (b) Classification. Class...

  20. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting... pulmonary embolism by measuring the coagulation time of whole blood. (b) Classification. Class...

  1. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting... pulmonary embolism by measuring the coagulation time of whole blood. (b) Classification. Class...

  2. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting... pulmonary embolism by measuring the coagulation time of whole blood. (b) Classification. Class...

  3. A comparative study of tissue factor and kaolin on blood coagulation assays using rotational thromboelastometry and thromboelastography.

    PubMed

    Peng, Henry T; Grodecki, Richard; Rizoli, Sandro; Shek, Pang N

    2016-01-01

    Rotational thromboelastometry (ROTEM) and thromboelastography (TEG) have been increasingly used to diagnose acute coagulopathy and guide blood transfusion. The tests are routinely performed using different triggering activators such as tissue factor and kaolin, which activate different pathways yielding different results. To optimize the global blood coagulation assays using ROTEM and TEG, we conducted a comparative study on the activation methods employing tissue factor and kaolin at different concentrations as well as standard reagents as recommended by the manufacturer of each device. Key parameter values were obtained at various assay conditions to evaluate and compare coagulation and fibrinolysis profiles of citrated whole blood collected from healthy volunteers. It was found that tissue factor reduced ROTEM clotting time and TEG R, and increased ROTEM clot formation time and TEG K in a concentration-dependent manner. In addition, tissue factor affected ROTEM alpha angle, and maximum clot firmness, especially in the absence of kaolin activation, whereas both ROTEM and TEG clot lysis (LI30, CL30, and LY30) remained unaffected. Moreover, kaolin reduced ROTEM clotting time and TEG R and K, but to a lesser extent than tissue factor, in-tem and ex-tem. Correlations in all corresponding parameters between ROTEM and TEG were observed, when the same activators were used in the assays compared with lesser correlations between standard kaolin TEG and ROTEM (INTEM/EXTEM). The two types of viscoelastic point-of-care devices provide different results, depending on the triggering reagent used to perform the assay. Optimal assay condition was obtained to reduce assay time and improve assay accuracy.

  4. Treatment of Epilepsy with Bipolar Electro-coagulation: An Analysis of Cortical Blood Flow and Histological Change in Temporal Lobe

    PubMed Central

    Cui, Zhi-Qiang; Luan, Guo-Ming; Zhou, Jian; Zhai, Feng; Guan, Yu-Guang; Bao, Min

    2015-01-01

    Background: Bipolar electro-coagulation has a reported efficacy in treating epilepsy involving functional cortex by pure electro-coagulation or combination with resection. However, the mechanisms of bipolar electro-coagulation are not completely known. We studied the acute cortical blood flow and histological changes after bipolar electro-coagulation in 24 patients with intractable temporal lobe epilepsy. Methods: Twenty-four patients were consecutively enrolled, and divided into three groups according to the date of admission. The regional cortical blood flow (rCBF), electrocorticography, the depth of cortex damage, and acute histological changes (H and E staining, neuronal staining and neurofilament (NF) staining) were analyzed before and after the operation. The t-test analysis was used to compare the rCBF before and after the operation. Results: The rCBF after coagulation was significantly reduced (P < 0.05). The spikes were significantly reduced after electro-coagulation. For the temporal cortex, the depth of cortical damage with output power of 2–9 W after electro-coagulation was 0.34 ± 0.03, 0.48 ± 0.06, 0.69 ± 0.06, 0.84 ± 0.09, 0.98 ± 0.08, 1.10 ± 0.11, 1.11 ± 0.09, and 1.22 ± 0.11 mm, respectively. Coagulation with output power of 4–5 W completely damaged the neurons and NF protein in the molecular layer, external granular layer, and external pyramidal layer. Conclusions: The electro-coagulation not only destroyed the neurons and NF protein, but also reduced the rCBF. We concluded that the injuries caused by electro-coagulation would prevent horizontal synchronization and spread of epileptic discharges, and partially destroy the epileptic focus. PMID:25591564

  5. Mast cell-restricted tetramer-forming tryptases and their beneficial roles in hemostasis and blood coagulation.

    PubMed

    Prieto-García, Alicia; Castells, Mariana C; Hansbro, Philip M; Stevens, Richard L

    2014-05-01

    Tetramer-forming tryptase (hTryptase-β) was recently discovered to have a prominent role in preventing the internal accumulation of life-threatening fibrin deposits and fibrin-platelet clots. The anticoagulant activity of hTryptase-β is an explanation for the presence of hemorrhagic disorders in some patients with anaphylaxis or mastocytosis. The fragments of hFibrinogen formed by the proteolysis of this prominent protein by hTryptase-β could be used as biomarkers in the blood and/or urine for the identification and monitoring of patients with mast cell-dependent disorders. Recombinant hTryptase-β has potential to be used in clinical settings where it is desirable to inhibit blood coagulation.

  6. Effect of Australian elapid venoms on blood coagulation: Australian Snakebite Project (ASP-17).

    PubMed

    Gulati, Abhishek; Isbister, Geoffrey K; Duffull, Stephen B

    2013-01-01

    Snake venoms contain toxins that activate the coagulation network and cause venom-induced consumption coagulopathy. A previously developed mathematical model of the coagulation network was refined and used to describe and predict the time course of changes in the coagulation factors following envenomation by Brown snake (Pseudonaja spp.), Tiger snake (Notechis scutatus), Rough-scaled snake (Tropidechis carinatus) and Hoplocephalus spp. (Stephens banded, Pale headed and Broad headed). Simulations of the time course of the change in coagulation factors were compared to data obtained from a large prospective study of Australian snake bites - the Australian Snakebite Project. The model predictions were also compared against data for partial and complete VICC obtained from the same study. The model simulations were used to understand the differences in consumption and recovery of clotting factors in partial versus complete VICC as well as among bites from different snake types. The model suggested that the venoms were absorbed almost instantaneously and provided a reasonable prediction of the observed concentration of clotting factors over time in patients bitten by Australian elapid snakes. The model predictions suggested a higher consumption of factors (fibrinogen, II and IX in particular) in patients with complete VICC compared to those with partial VICC. The model also predicted that snakes with "Xa-like" venoms may produce a less severe VICC than snakes with "Xa:Va-like" venoms.

  7. Possibly propylthiouracil-induced antineutrophilic cytoplasmic antibody-associated vasculitis manifested as blood coagulation disorders

    PubMed Central

    Yi, Xiao-Yan; Wang, Yao; Li, Qi-Fu; Li, Rong; Yang, Shu-Min; Zhou, Guo-Qing; Wang, Zhi-Hong

    2016-01-01

    Abstract Background: Propylthiouracil is the most common drug used to treat hyperthyroidism. However, this drug could cause a severe disease, antineutrophilic cytoplasmic antibody-associated vasculitis (AAV), which was usually misdiagnosed. Methods: We reported a 60-year-old woman of propylthiouracil-induced AAV manifested as blood coagulation disorders. The patient was admitted because of hyperthyroidism and leukopenia. At the time of hospitalization, she suffered from dry cough, erythema and knee joints ache, and gradually became febrile. And then BP decreased and PLT was reduced with coagulation disorders. ANCA: c-ANCA positive (1:100), p-ANCA positive (1:320), MPO-IgG positive, PR3-IgG positive, GBM-IgG negative. Erythrocyte sedimentation rate and C-reactive protein increased markedly. Chest high-resolution computed tomography (HRCT) showed that scattered spots, patch and ground-glass opacity. Results: Finally, we made a terminal diagnosis of PTU-induced AAV possibly. After drug withdrawal and use of steroid, the patient recovered well and then accepted RAI therapy. As the patient was given imipenem-cilastatin before the reduction of PLT and coagulation disorders, we considered that the hematologic disorders might be caused by antibiotics or a clinical presentation of the vasculitis itself. Conclusion: Drug-induced vasculitis is relatively good prognosis, but early diagnosis and timely withdrawal of associated drugs are the key to the treatment. PMID:27741122

  8. Contributions of contact activation pathways of coagulation factor XII in plasma.

    PubMed

    Chatterjee, Kaushik; Guo, Zhe; Vogler, Erwin A; Siedlecki, Christopher A

    2009-07-01

    Activation of human blood plasma coagulation by contact with hydrophilic or hydrophobic surfaces (procoagulants) is dominated by kallikrein (Kal)-mediated activation of the blood zymogen FXII (Hageman Factor). Mathematical modeling of prekallikrein (PK)-deficient platelet-poor plasma (d(PK)PPP) and PK-reconstituted d(PK)PPP (Rd(PK)PPP) coagulation shows that autoactivation of FXII (FXII-->[surface]FXII) produces no more than about 25% of the total FXIIa produced by the intrinsic pathway. Autoactivation and reciprocal-activation increase in the same proportion with procoagulant surface energy (water-wettability), whereas total amount of FXIIa produced per-unit-area procoagulant remains roughly constant for any particular procoagulant. These results suggest that procoagulant surfaces initiate the intrinsic cascade by producing a bolus of FXIIa in proportion to surface energy or surface area but play no additional role in subsequent molecular events in the cascade. Results further suggest that reciprocal-activation occurs in proportion to the amount of FXIIa produced by the initiating autoactivation step.

  9. Coagulation activity and white thrombus formation in the microminipig.

    PubMed

    Miura, Naoki; Kawaguchi, Hiroaki; Nagasato, Tomoka; Yamada, Tomonobu; Ito, Takashi; Izumi, Hiroyuki; Shameshima, Hisayo; Miyoshi, Noriaki; Tanimoto, Akihide; Maruyama, Ikuro

    2013-01-01

    Swine are becoming increasingly attractive as animal models for clinical research and the recently developed Microminipig (MMPig) has emerged as a possible experimental animal model. In this study, we demonstrated age-dependent changes in hematological parameters and coagulation activity in healthy MMPigs (58 male and 67 females, aged 0-34 months), and investigated white thrombus formation (WTF) using an in vitro microchip flow-chamber system (four males and four females, aged 22-23 months). There was no clear sex or age-dependent differences in any hematological parameters. While activated partial thromboplastin time (APTT) was shorter than prothrombin time (PT), with APTT:PT of 0.88:1, microchip flow-chamber system analysis showed that WTF time was shorter than that in humans, suggesting a possible thrombotic tendency in the MMPig. These results could be useful to life science researchers in the use of the MMPig as an experimental model animal for thrombus formation. PMID:23606691

  10. Reduced Blood Coagulation on Roll-to-Roll, Shrink-Induced Superhydrophobic Plastics.

    PubMed

    Nokes, Jolie M; Liedert, Ralph; Kim, Monica Y; Siddiqui, Ali; Chu, Michael; Lee, Eugene K; Khine, Michelle

    2016-03-01

    The unique antiwetting properties of superhydrophobic (SH) surfaces prevent the adhesion of water and bodily fluids, including blood, urine, and saliva. While typical manufacturable approaches to create SH surfaces rely on chemical and structural modifications, such approaches are expensive, require postprocessing, and are often not biocompatible. By contrast, it is demonstrated that purely structural SH features are easily formed using high throughput roll-to-roll (R2R) manufacturing by shrinking a prestressed thermoplastic with a thin, stiff layer of silver and calcium. These features are subsequently embossed into any commercially available and Food and Drug Administration (FDA)-approved plastic. The R2R SH surfaces have contact angles >150° and contact angle hysteresis <10°. Importantly, the surfaces minimize blood adhesion, leading to reduced blood coagulation without the need for anticoagulants. SH surfaces have >4200× reduction of blood residue area compared to the nonstructured controls of the same material. In addition, blood clotting is reduced >5× using whole blood directly from the patient. Furthermore, these surfaces can be easily configured into 3D shapes, as demonstrated with SH tubes. With the simple scale-up production and the eliminated need for anticoagulants to prevent clotting, the proposed conformable SH surfaces can be impactful for a wide range of medical tools, including catheters and microfluidic channels. PMID:26784916

  11. [INFLUENCE OF THE INTRA-ABDOMINAL HYPERTENSION ON THE BLOOD COAGULATION SYSTEM (EXPERIMENTAL STUDY)].

    PubMed

    Turgunov, Y; Matyushko, D; Nurbekov, A; Kaliyeva, D; Alibekov, A

    2016-07-01

    The analysis of the influence of the intra-abdominal hypertension on the blood coagulation system by carrying out an experimental research with laboratory animals is presented in article. After simulating intra-abdominal hypertension with different degree and exposition we made the laboratory research of blood coagulation system (fibrinogen, PTI, SFMC, APTT) and ELISA research on the concentration of the modern marker of thrombozis - D-dimer. The results in article clearly demonstrate that there is a direct linear dependence of level of fibrinogen and SFMC on degree of intra-abdominal hypertension, and the multidirectional changes of indicators with increase of intra-abdominal hypertension duration - towards hypercoagulation for 3-12 hours, and then by 24 o'clock - in the opposite direction towards hypocoagulation. Perhaps, it is explained with development of organ dysfunction and a coagulopathy of consumption. Indicator D-dimer has also direct linear dependence on the intra-abdominal hypertension level with contents peak at 3 hour exposition, and at all intra-abdominal hypertension levels, more than 2-fold rise of D-dimer level is statistically significant. PMID:27661285

  12. Activation of coagulation factor XI, without detectable contact activation in dengue haemorrhagic fever.

    PubMed

    van Gorp, E C; Minnema, M C; Suharti, C; Mairuhu, A T; Brandjes, D P; ten Cate, H; Hack, C E; Meijers, J C

    2001-04-01

    A prospective cohort study was performed in 50 patients with dengue haemorrhagic fever (DHF) to determine the potential role of the contact activation system and factor XI activation (intrinsic pathway) in the coagulation disorders in DHF. To establish whether TAFI (thrombin-activatable fibrinolysis inhibitor) was involved in the severity of the coagulation disorders, the TAFI antigen and activity levels were also determined. Markers of contact activation (kallikrein--C1-inhibitor complexes), the intrinsic pathway of coagulation (factor XIa--C1-inhibitor complexes) and TAFI were measured and correlated to thrombin generation markers (thrombin--anti-thrombin complexes (TAT), prothrombin fragment 1+2 (F1+2)) and a marker for fibrinolysis [plasmin--alpha 2--anti-plasmin complexes (PAP)]. Activation of the intrinsic pathway of coagulation was clearly demonstrated by elevated levels of factor XIa--C1-inhibitor complexes, without evidence of contact activation, reflected by undetectable kallikrein--C1-inhibitor complexes. Both TAFI antigen and activity levels were decreased in all patients, which may contribute to the severity of bleeding complications in DHF because of the impaired capacity of the coagulation system to protect the fibrin clot from fibrinolysis. These findings in a human viral infection model are in accordance with earlier findings in bacterial sepsis.

  13. [Effect of rhG-CSF on blood coagulation in beagles irradiated by 2.3 Gy neutron].

    PubMed

    Li, Ming; Han, Qin-Fang; Liu, Xiao-Lan; Xing, Shuang; Xiong, Guo-Lin; Xie, Ling; Zhao, Yan-Fang; Yu, Zu-Yin; Ding, Yi-Bo; Zhao, Zhen-Hu; Cong, Yu-Wen; Luo, Qing-Liang

    2010-12-01

    The aim of this study was to investigate the effect of recombinant human granulocyte stimulating factor (rhG-CSF) on blood coagulation of beagles irradiated by 2.3 Gy neutron so as to provide new therapy for blood coagulation disorder after neutron irradiation. 10 beagles were exposed to 2.3 Gy neutron, and then randomly assigned into supportive care group and rhG-CSF-treated group. The rhG-CSF-treated cohorts were injected subcutaneously with rhG-CSF (10 µg/kg·d) beginning at the day of exposure for 21 consecutive days. Peripheral blood platelet counts were examined once every two days. In vitro platelet aggregation test, thromboelastography and blood clotting tetrachoric tests were also performed. The results indicated that the blood clotting system of irradiated dogs was in hypercoagulable state in the early days after 2.3 Gy neutron irradiation, and became hypocoagulable at crisis later and were mainly on intrinsic coagulation pathway. Blood fibrinogen increased markedly during the course of disease, while platelet counts and aggregation function were decreased remarkably. rhG-CSF administered daily could correct hypercoagulable state induced by 2.3 Gy neutron irradiation at the early time post exposure, shortened the thromboplastin generation time and clotting formation, down-regulated the abnormal high fibrinogen in blood, and improved platelet aggregation function. It is concluded that rhG-CSF can improve coagulation disorders of irradiated dogs.

  14. Probing the coagulation pathway with aptamers identifies combinations that synergistically inhibit blood clot formation.

    PubMed

    Bompiani, Kristin M; Lohrmann, Jens L; Pitoc, George A; Frederiksen, James W; Mackensen, George B; Sullenger, Bruce A

    2014-08-14

    Coordinated enzymatic reactions regulate blood clot generation. To explore the contributions of various coagulation enzymes in this process, we utilized a panel of aptamers against factors VIIa, IXa, Xa, and prothrombin. Each aptamer dose-dependently inhibited clot formation, yet none was able to completely impede this process in highly procoagulant settings. However, several combinations of two aptamers synergistically impaired clot formation. One extremely potent aptamer combination was able to maintain human blood fluidity even during extracorporeal circulation, a highly procoagulant setting encountered during cardiopulmonary bypass surgery. Moreover, this aptamer cocktail could be rapidly reversed with antidotes to restore normal hemostasis, indicating that even highly potent aptamer combinations can be rapidly controlled. These studies highlight the potential utility of using sets of aptamers to probe the functions of proteins in molecular pathways for research and therapeutic ends.

  15. Tissue factor pathway inhibitor dose-dependently inhibits coagulation activation without influencing the fibrinolytic and cytokine response during human endotoxemia.

    PubMed

    de Jonge, E; Dekkers, P E; Creasey, A A; Hack, C E; Paulson, S K; Karim, A; Kesecioglu, J; Levi, M; van Deventer, S J; van Der Poll, T

    2000-02-15

    Inhibition of the tissue factor pathway has been shown to attenuate the activation of coagulation and to prevent death in a gram-negative bacteremia primate model of sepsis. It has been suggested that tissue factor influences inflammatory cascades other than the coagulation system. The authors sought to determine the effects of 2 different doses of recombinant tissue factor pathway inhibitor (TFPI) on endotoxin-induced coagulant, fibrinolytic, and cytokine responses in healthy humans. Two groups, each consisting of 8 healthy men, were studied in a double-blind, randomized, placebo-controlled crossover study. Subjects were studied on 2 different occasions. They received a bolus intravenous injection of 4 ng/kg endotoxin, which was followed by a 6-hour continuous infusion of TFPI or placebo. Eight subjects received 0.05 mg/kg per hour TFPI after a bolus of 0.0125 mg/kg (low-dose group), and 8 subjects received 0.2 mg/kg per hour after a bolus of 0.05 mg/kg (high-dose group). Endotoxin injection induced the activation of coagulation, the activation and subsequent inhibition of fibrinolysis, and the release of proinflammatory and antiinflammatory cytokines. TFPI infusion induced a dose-dependent attenuation of thrombin generation, as measured by plasma F1 + 2 and thrombin-antithrombin complexes, with a complete blockade of coagulation activation after high-dose TFPI. Endotoxin-induced changes in the fibrinolytic system and cytokine levels were not altered by either low-dose or high-dose TFPI. The authors concluded that TFPI effectively and dose-dependently attenuates the endotoxin-induced coagulation activation in humans without influencing the fibrinolytic and cytokine response. (Blood. 2000;95:1124-1129)

  16. Scaling of cluster growth for coagulating active particles.

    PubMed

    Cremer, Peet; Löwen, Hartmut

    2014-02-01

    Cluster growth in a coagulating system of active particles (such as microswimmers in a solvent) is studied by theory and simulation. In contrast to passive systems, the net velocity of a cluster can have various scalings dependent on the propulsion mechanism and alignment of individual particles. Additionally, the persistence length of the cluster trajectory typically increases with size. As a consequence, a growing cluster collects neighboring particles in a very efficient way and thus amplifies its growth further. This results in unusual large growth exponents for the scaling of the cluster size with time and, for certain conditions, even leads to "explosive" cluster growth where the cluster becomes macroscopic in a finite amount of time.

  17. Metallic oxide nanoparticles stimulate blood coagulation independent of their surface charge.

    PubMed

    Steuer, Heiko; Krastev, Rumen; Lembert, Nicolas

    2014-07-01

    Positively charged metallic oxides prevent blood coagulation whereas negatively charged metallic oxides are thrombogenic. This study was performed to examine whether this effect extends to metallic oxide nanoparticles. Oscillation shear rheometry was used to study the effect of zinc oxide and silicon dioxide nanoparticles on thrombus formation in human whole blood. Our data show that oscillation shear rheometry is a sensitive and robust technique to analyze thrombogenicity induced by nanoparticles. Blood without previous contact with nanoparticles had a clotting time (CT) of 16.7 ± 1.0 min reaching a maximal clot strength (CS) of 16 ± 14 Pa (G') after 30 min. ZnO nanoparticles (diameter 70 nm, +37 mV zeta-potential) at a concentration of 1 mg/mL prolonged CT to 20.8 ± 3.6 min and provoked a weak clot (CS 1.5 ± 1.0 Pa). However, at a lower concentration of 100 µg/mL the ZnO particles dramatically reduced CT to 6.0 ± 0.5 min and increased CS to 171 ± 63 Pa. This procoagulant effect decreased at lower concentrations reaching the detection limit at 10 ng/mL. SiO2 nanoparticles (diameter 232 nm, -28 mV zeta-potential) at high concentrations (1 mg/mL) reduced CT (2.1 ± 0.2 min) and stimulated CS (249 ± 59 Pa). Similar to ZnO particles, this procoagulant effect reached a detection limit at 10 ng/mL. Nanoparticles in high concentrations reproduce the surface charge effects on blood coagulation previously observed with large particles or solid metal oxides. However, nanoparticles with different surface charges equally well stimulate coagulation at lower concentrations. This stimulation may be an effect which is not directly related to the surface charge.

  18. Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

    SciTech Connect

    Ogami, M; Kulkarni, R; Wang, H; Reif, R; Wang, R K

    2014-08-31

    We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing. (laser biophotonics)

  19. Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

    NASA Astrophysics Data System (ADS)

    Ogami, M.; Kulkarni, R.; Wang, H.; Reif, R.; Wang, R. K.

    2014-08-01

    We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing.

  20. Acute effects of calcium supplements on blood pressure and blood coagulation: secondary analysis of a randomised controlled trial in post-menopausal women.

    PubMed

    Bristow, Sarah M; Gamble, Greg D; Stewart, Angela; Horne, Anne M; Reid, Ian R

    2015-12-14

    Recent evidence suggests that Ca supplements increase the risk of cardiovascular events, but the mechanism(s) by which this occurs is uncertain. In a study primarily assessing the effects of various Ca supplements on blood Ca levels, we also investigated the effects of Ca supplements on blood pressure and their acute effects on blood coagulation. We randomised 100 post-menopausal women to 1 g/d of Ca or a placebo containing no Ca. Blood pressure was measured at baseline and every 2 h up to 8 h after their first dose and after 3 months of supplementation. Blood coagulation was measured by thromboelastography (TEG) in a subgroup of participants (n 40) up to 8 h only. Blood pressure declined over 8 h in both the groups, consistent with its normal diurnal rhythm. The reduction in systolic blood pressure was smaller in the Ca group compared with the control group by >5 mmHg between 2 and 6 h (P≤0·02), and the reduction in diastolic blood pressure was smaller at 2 h (between-groups difference 4·5 mmHg, P=0·004). Blood coagulability, assessed by TEG, increased from baseline over 8 h in the calcium citrate and control groups. At 4 h, the increase in the coagulation index was greater in the calcium citrate group compared with the control group (P=0·03), which appeared to be due to a greater reduction in the time to clot initiation. These data suggest that Ca supplements may acutely influence blood pressure and blood coagulation. Further investigation of this possibility is required.

  1. Enhanced specificity of immunoblotting using radiolabeled antigen overlay: studies of blood coagulation factor XII and prekallikrein in plasma

    SciTech Connect

    Laemmle, B.; Berrettini, M.; Griffin, J.H.

    1986-01-01

    Immunoblotting of blood coagulation Factor XII and plasma prekallikrein in whole plasma was performed using radiolabeled antigen for detection. After sodium dodecyl sulfate-polyacrylamide gel electrophoresis of plasma and transfer to nitrocellulose sheets, the blots were first reacted with polyclonal goat anti-Factor XII or anti-prekallikrein antisera and then with /sup 125/I-Factor XII or /sup 125/I-prekallikrein, respectively. A major advantage of using radiolabeled antigen rather than radiolabeled secondary antibody was enhanced specificity of immunodetection of these antigens in plasma. This procedure was sensitive to approx.0.3 ng of either Factor XII or prekallikrein antigen and was useful for detection of Factor XII cleavage fragments in contact activated plasma. Radiolabeled antigen overlay may improve the specificity of immunoblotting of trace antigens in any complex mixtures.

  2. Physicochemical characterization of human S-protein and its function in the blood coagulation system.

    PubMed Central

    Preissner, K T; Wassmuth, R; Müller-Berghaus, G

    1985-01-01

    S-protein, the main inhibitor of the assembly of the membrane attack complex of complement, was isolated from human plasma by a simple purification procedure, which includes barium citrate adsorption, ammonium sulphate precipitation, chromatography on DEAE-Sephacel and Blue Sepharose and gel filtration on Sephacryl S-200. The homogeneous protein (sedimentation coefficient 4.6 S) was obtained in approx. 5% yield relative to its concentration in plasma, which was found to be 0.3-0.5 mg/ml. The final product did not cross-react with antisera against complement proteins or other proteinase inhibitors of human plasma. On polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate, S-protein migrated as a single-chain band with an apparent Mr of 74000 under non-reducing conditions and as a doublet of Mr 78000 and 65000 upon reduction. In plasma or serum S-protein also existed in two forms of corresponding Mr values, as was evidenced by an immunoblot enzyme-linked immunosorbent assay technique. S-protein was found to be an acidic glycoprotein with 10% (W/W) carbohydrate content and several isoelectric points in the range pH 4.75-5.25, and it contained one free thiol group per molecule of protein. The functional properties of S-protein in the complement system were demonstrated by its ability to inhibit complement-dependent cell lysis in a concentration-dependent manner (Ki 0.6 microM) and by its incorporation into the nascent SC5b-7 complex. A new function for S-protein could be revealed in the blood coagulation system. The slow progressive inhibition of thrombin by antithrombin III was not affected by S-protein, whereas the purified protein interfered with the fast inactivation of thrombin clotting as well as amidolytic activity by antithrombin III-heparin complex. The acceleration of this inhibition reaction by heparin was counteracted by S-protein, indicating the ability of S-protein to neutralize heparin activity. Images PMID:4062902

  3. Assessment of coagulation disorders and cancer procoagulant activity in patients with myelodysplastic syndromes.

    PubMed

    Chojnowski, K; Treliński, J; Wawrzyniak, E; Sobolewska, M; Mielicki, W

    2002-01-01

    Hemostatic disorders mainly due to thrombocytopenia represent an important clinical problem in patients with myelodysplastic syndromes (MDS). Much less is known about the possible coagulation abnormalities. Thirty patients with MDS were studied. Activity of cancer procoagulant (CP), concentrations of activation markers of coagulation and fibrinolysis such as thrombin-antithrombin complexes (TAT), prothrombin fragment 1+2 (F1+2) and D-dimers (DD) as well as standard coagulation tests were determined. Coagulation abnormalities concerned mainly patients with RAEB and RAEB-t. In this group the mean values of TATand F1+2 concentrations were significantly higher than in control indicating chronic coagulation activation similar to that observed in acute leukemias. CP activity in MDS patients did not differ from the control group.

  4. Thrombin generation and fibrin clot formation under hypothermic conditions: an in vitro evaluation of tissue factor initiated whole blood coagulation

    PubMed Central

    Whelihan, Matthew F.; Kiankhooy, Armin; Brummel-Ziedins, Kathleen

    2015-01-01

    Background Despite trauma-induced hypothermic coagulopathy being familiar in the clinical setting, empirical experimentation concerning this phenomenon is lacking. In this study we investigated the effects of hypothermia on thrombin generation, clot formation and global hemostatic functions in an in vitro environment using a whole blood model and thromboelastography (TEG) which can recapitulate hypothermia. Methods Blood was collected from healthy individuals through venipuncture and treated with corn trypsin inhibitor, to block the contact pathway. Coagulation was initiated with 5pM tissue factor at temperatures 37°C, 32°C, and 27°C. Reactions were quenched over time with soluble and insoluble components of each time point analyzed for thrombin generation, fibrinogen consumption, factor (f)XIII activation and fibrin deposition. Global coagulation potential was evaluated through TEG. Results Data showed that thrombin generation in samples at 37°C and 32°C had comparable rates while 27°C had a much lower rate (39.2 ± 1.1 and 43 ± 2.4 nM/min vs 28.6 ± 4.4 nM/min, respectively). Fibrinogen consumption and fXIII activation were highest at 37°C followed by 32°C and 27°C (13.8 ± 2.9 percent/min vs 7.8 ± 1.8 percent/min, respectively). Fibrin formation as seen through clot weights also followed this trend. TEG data showed clot formation was fastest in samples at 37°C and lowest at 27°C. Maximum clot strength was similar for each temperature. Also, percent lysis of clots was highest at 37°C followed by 32°C and then 27°C. Conclusions Induced hypothermic conditions directly affect the rate of thrombin generation and clot formation while global clot stability remains intact. PMID:24331944

  5. Sphingosine-1-Phosphate and Its Receptors: A Mutual Link between Blood Coagulation and Inflammation

    PubMed Central

    Mahajan-Thakur, Shailaja; Böhm, Andreas; Jedlitschky, Gabriele; Schrör, Karsten; Rauch, Bernhard H.

    2015-01-01

    Sphingosine-1-phosphate (S1P) is a versatile lipid signaling molecule and key regulator in vascular inflammation. S1P is secreted by platelets, monocytes, and vascular endothelial and smooth muscle cells. It binds specifically to a family of G-protein-coupled receptors, S1P receptors 1 to 5, resulting in downstream signaling and numerous cellular effects. S1P modulates cell proliferation and migration, and mediates proinflammatory responses and apoptosis. In the vascular barrier, S1P regulates permeability and endothelial reactions and recruitment of monocytes and may modulate atherosclerosis. Only recently has S1P emerged as a critical mediator which directly links the coagulation factor system to vascular inflammation. The multifunctional proteases thrombin and FXa regulate local S1P availability and interact with S1P signaling at multiple levels in various vascular cell types. Differential expression patterns and intracellular signaling pathways of each receptor enable S1P to exert its widespread functions. Although a vast amount of information is available about the functions of S1P and its receptors in the regulation of physiological and pathophysiological conditions, S1P-mediated mechanisms in the vasculature remain to be elucidated. This review summarizes recent findings regarding the role of S1P and its receptors in vascular wall and blood cells, which link the coagulation system to inflammatory responses in the vasculature. PMID:26604433

  6. Fat emulsion infusion potentiates coagulation activation during human endotoxemia.

    PubMed

    van der Poll, T; Coyle, S M; Levi, M; Boermeester, M A; Braxton, C C; Jansen, P M; Hack, C E; Lowry, S F

    1996-01-01

    Intravenous fat emulsions are frequently given to malnourished patients who are prone to suffer from infectious complications. As injection of low dose endotoxin represents a model to study the human response to acute infection, we sought to determine the effect of lipid emulsion infusion on endotoxin-induced activation of the hemostatic mechanism in man. Ten healthy men received a bolus intravenous injection of endotoxin (lot EC-5; 20 U/kg) midway through a 4-h infusion (125 ml/h) of either dextrose 5% (n = 5) or Intralipid 20% (n = 5). Lipid infusion potentiated endotoxin-induced coagulation activation, as indicated by higher plasma levels of the prothrombin fragment F1 + 2 and of thrombin-antithrombin III complexes (both p < 0.05 for the difference between groups). However, lipid infusion did not influence the fibrinolytic response to intravenous endotoxin, as reflected by similar increases in the levels of tissue-type plasminogen activator and plasmin-alpha 2-antiplasmin complexes in both groups. Endotoxin-induced appearance of plasminogen activator inhibitor type I was enhanced by lipid infusion (p < 0.05). These data suggest that fat emulsion infusion may enhance the tendency towards thrombotic complications in patients with infections.

  7. Hepatocyte tissue factor activates the coagulation cascade in mice

    PubMed Central

    Sullivan, Bradley P.; Kopec, Anna K.; Joshi, Nikita; Cline, Holly; Brown, Juliette A.; Bishop, Stephanie C.; Kassel, Karen M.; Rockwell, Cheryl; Mackman, Nigel

    2013-01-01

    In this study, we characterized tissue factor (TF) expression in mouse hepatocytes (HPCs) and evaluated its role in mouse models of HPC transplantation and acetaminophen (APAP) overdose. TF expression was significantly reduced in isolated HPCs and liver homogenates from TFflox/flox/albumin-Cre mice (HPCΔTF mice) compared with TFflox/flox mice (control mice). Isolated mouse HPCs expressed low levels of TF that clotted factor VII-deficient human plasma. In addition, HPC TF initiated factor Xa generation without exogenous factor VIIa, and TF activity was increased dramatically after cell lysis. Treatment of HPCs with an inhibitory TF antibody or a cell-impermeable lysine-conjugating reagent prior to lysis substantially reduced TF activity, suggesting that TF was mainly present on the cell surface. Thrombin generation was dramatically reduced in APAP-treated HPCΔTF mice compared with APAP-treated control mice. In addition, thrombin generation was dependent on donor HPC TF expression in a model of HPC transplantation. These results suggest that mouse HPCs constitutively express cell surface TF that mediates activation of coagulation during hepatocellular injury. PMID:23305736

  8. Interest of ICG blood clearance monitoring for reproducible 810-nm diode laser coagulation of blood vessels

    NASA Astrophysics Data System (ADS)

    Desmettre, Thomas; Soulie-Begu, Sylvie; Devoisselle, Jean-Marie; Mordon, Serge R.

    1999-02-01

    Purpose: To evaluate a method of control of diode laser fluence leading to a reproducible ICG-enhanced selective photocoagulation of blood vessels. This method would use the chromophore clearance, i.e. ICG blood concentration decay to adapt the laser fluence. Materials and Methods: A skin flap window was used on hamsters. After a 15 mg/kg ICG solution injection, photocoagulation of vessels were performed. Results: Selective photocoagulation of blood vessels was obtained only during the first 10 minutes. The fluence required to obtain a selective photocoagulation of vessels (F) was modelized using a one compartment phamacokinetic equation: F equals Of(1-e-t/(tau )). The best fit was obtained for a time constant (tau) equals 4.8 min and Of equals 300 J/cm2 (correlation coefficient r2 equals 0.996). During the first 10 minutes, the fluence required for selective photocoagulation of vessels was increased by a factor 4.5. Conclusion: Fluence required for a selective photocoagulation of vessels was correlated to ICG blood concentration decay. The time constant was equivalent to ICG half-life time in human blood. These results demonstrate that diode laser ICG-enhanced photocoagulation can be controlled by monitoring the ICG blood clearance.

  9. Activation loop 3 and the 170 loop interact in the active conformation of coagulation factor VIIa.

    PubMed

    Persson, Egon; Olsen, Ole H

    2009-06-01

    The initiation of blood coagulation involves tissue factor (TF)-induced allosteric activation of factor VIIa (FVIIa), which circulates in a zymogen-like state. In addition, the (most) active conformation of FVIIa presumably relies on a number of intramolecular interactions. We have characterized the role of Gly372(223) in FVIIa, which is the sole residue in activation loop 3 that is capable of forming backbone hydrogen bonds with the unusually long 170 loop and with activation loop 2, by studying the effects of replacement with Ala [G372(223)A]. G372A-FVIIa, both in the free and TF-bound form, exhibited reduced cleavage of factor X (FX) and of peptidyl substrates, and had increased K(m) values compared with wild-type FVIIa. Inhibition of G372A-FVIIa.sTF by p-aminobenzamidine was characterized by a seven-fold higher K(i) than obtained with FVIIa.sTF. Crystallographic and modelling data suggest that the most active conformation of FVIIa depends on the backbone hydrogen bond between Gly372(223) and Arg315(170C) in the 170 loop. Despite the reduced activity and inhibitor susceptibility, native and active site-inhibited G372A-FVIIa bound sTF with the same affinity as the corresponding forms of FVIIa, and burial of the N-terminus of the protease domain increased similarly upon sTF binding to G372A-FVIIa and FVIIa. Thus Gly372(223) in FVIIa appears to play a critical role in maturation of the S1 pocket and adjacent subsites, but does not appear to be of importance for TF binding and the ensuing allostery. PMID:19490111

  10. Short-term Effects of Air Temperature on Blood Markers of Coagulation and Inflammation in Potentially Susceptible Individuals

    EPA Science Inventory

    Objectives: Changes in air temperature are associated with an increase in cardiovascular events, but the role of pro-coagulant and pro-inflammatory blood markers is still poorly understood. We investigated the association between air temperature and fibrinogen, plasminogen act...

  11. The effects of perioperatively administered crystalloids and colloids on concentrations of molecular markers of activated coagulation and fibrinolysis.

    PubMed

    Fries, Dietmar; Streif, Werner; Margreiter, Josef; Klingler, Anton; Kühbacher, Gabriele; Schobersberger, Wolfgang; Wirleitner, Barbara; Innerhofer, Petra

    2004-04-01

    To explore whether intravenous administration of routinely used crystalloid or colloid solutions differently affects the coagulation system, we investigated orthopaedic patients. Since crystalloid solutions might cause hypercoagulability, we here present our results on molecular markers of coagulation and fibrinolysis. Patients undergoing knee replacement surgery randomly received isovolemic amounts of lactated Ringer's solution, 6% hydroxyethyl starch 200/0.5 or 4% modified gelatine. Arterial blood samples for determination of specific molecular markers of activated coagulation (thrombin/antithrombin complex, D-dimer, prothrombin fragment F1 + 2), fibrinolysis (plasmin/alpha 2-antiplasmin complex, tissue plasminogen activator, plasminogen activator inhibitor-1), and concentrations of coagulation factor XIII were obtained at baseline, before tourniquet release, at the end of surgery and 2 h after operation. During the observation period, thrombin/antithrombin complex increased from 4.8 to 54.7 microg/l, D-dimer increased from 0.3 to 6.0 mg/ml, prothrombin fragment F1 + 2 increased from 1.7 to 5.9 nmol/l, tissue plasminogen activator decreased from 7.3 to 6.7 ng/ml, plasminogen activator inhibitor-1 increased from 68.4 to 71.0 ng/ml, plasmin/alpha 2-antiplasmin complex increased from 281.5 to 884 microg/l and factor XIII decreased from 89.0 to 58.5%. All parameters changed significantly but without any detectable difference in the response profile between the groups receiving different intravenous fluids. During knee replacement surgery a pronounced activation of the coagulation/fibrinolytic system was observed, regardless of whether patients received crystalloid or colloid fluids. Thus, these results cannot confirm the hypothesis that crystalloid fluids per se cause hypercoagulability in vivo.

  12. Blood coagulation factor XII drives adaptive immunity during neuroinflammation via CD87-mediated modulation of dendritic cells

    PubMed Central

    Göbel, Kerstin; Pankratz, Susann; Asaridou, Chloi-Magdalini; Herrmann, Alexander M.; Bittner, Stefan; Merker, Monika; Ruck, Tobias; Glumm, Sarah; Langhauser, Friederike; Kraft, Peter; Krug, Thorsten F.; Breuer, Johanna; Herold, Martin; Gross, Catharina C.; Beckmann, Denise; Korb-Pap, Adelheid; Schuhmann, Michael K.; Kuerten, Stefanie; Mitroulis, Ioannis; Ruppert, Clemens; Nolte, Marc W.; Panousis, Con; Klotz, Luisa; Kehrel, Beate; Korn, Thomas; Langer, Harald F.; Pap, Thomas; Nieswandt, Bernhard; Wiendl, Heinz; Chavakis, Triantafyllos; Kleinschnitz, Christoph; Meuth, Sven G.

    2016-01-01

    Aberrant immune responses represent the underlying cause of central nervous system (CNS) autoimmunity, including multiple sclerosis (MS). Recent evidence implicated the crosstalk between coagulation and immunity in CNS autoimmunity. Here we identify coagulation factor XII (FXII), the initiator of the intrinsic coagulation cascade and the kallikrein–kinin system, as a specific immune cell modulator. High levels of FXII activity are present in the plasma of MS patients during relapse. Deficiency or pharmacologic blockade of FXII renders mice less susceptible to experimental autoimmune encephalomyelitis (a model of MS) and is accompanied by reduced numbers of interleukin-17A-producing T cells. Immune activation by FXII is mediated by dendritic cells in a CD87-dependent manner and involves alterations in intracellular cyclic AMP formation. Our study demonstrates that a member of the plasmatic coagulation cascade is a key mediator of autoimmunity. FXII inhibition may provide a strategy to combat MS and other immune-related disorders. PMID:27188843

  13. Blood coagulation factor XII drives adaptive immunity during neuroinflammation via CD87-mediated modulation of dendritic cells.

    PubMed

    Göbel, Kerstin; Pankratz, Susann; Asaridou, Chloi-Magdalini; Herrmann, Alexander M; Bittner, Stefan; Merker, Monika; Ruck, Tobias; Glumm, Sarah; Langhauser, Friederike; Kraft, Peter; Krug, Thorsten F; Breuer, Johanna; Herold, Martin; Gross, Catharina C; Beckmann, Denise; Korb-Pap, Adelheid; Schuhmann, Michael K; Kuerten, Stefanie; Mitroulis, Ioannis; Ruppert, Clemens; Nolte, Marc W; Panousis, Con; Klotz, Luisa; Kehrel, Beate; Korn, Thomas; Langer, Harald F; Pap, Thomas; Nieswandt, Bernhard; Wiendl, Heinz; Chavakis, Triantafyllos; Kleinschnitz, Christoph; Meuth, Sven G

    2016-05-18

    Aberrant immune responses represent the underlying cause of central nervous system (CNS) autoimmunity, including multiple sclerosis (MS). Recent evidence implicated the crosstalk between coagulation and immunity in CNS autoimmunity. Here we identify coagulation factor XII (FXII), the initiator of the intrinsic coagulation cascade and the kallikrein-kinin system, as a specific immune cell modulator. High levels of FXII activity are present in the plasma of MS patients during relapse. Deficiency or pharmacologic blockade of FXII renders mice less susceptible to experimental autoimmune encephalomyelitis (a model of MS) and is accompanied by reduced numbers of interleukin-17A-producing T cells. Immune activation by FXII is mediated by dendritic cells in a CD87-dependent manner and involves alterations in intracellular cyclic AMP formation. Our study demonstrates that a member of the plasmatic coagulation cascade is a key mediator of autoimmunity. FXII inhibition may provide a strategy to combat MS and other immune-related disorders.

  14. Antimicrobial activity of fibrinogen and fibrinogen-derived peptides--a novel link between coagulation and innate immunity.

    PubMed

    Påhlman, L I; Mörgelin, M; Kasetty, G; Olin, A I; Schmidtchen, A; Herwald, H

    2013-05-01

    Fibrinogen is a key player in the blood coagulation system, and is upon activation with thrombin converted into fibrin that subsequently forms a fibrin clot. In the present study, we investigated the role of fibrinogen in the early innate immune response. Here we show that the viability of fibrinogen-binding bacteria is affected in human plasma activated with thrombin. Moreover, we found that the peptide fragment GHR28 released from the β-chain of fibrinogen has antimicrobial activity against bacteria that bind fibrinogen to their surface, whereas non-binding strains are unaffected. Notably, bacterial killing was detected in Group A Streptococcus bacteria entrapped in a fibrin clot, suggesting that fibrinogen and coagulation is involved in the early innate immune system to quickly wall off and neutralise invading pathogens.

  15. Classical Notions of Coagulation Revisited in Relation with Blood Losses, Transfusion Rate for 700 Consecutive Liver Transplantations.

    PubMed

    Massicotte, Luc; Thibeault, Lynda; Roy, André

    2015-07-01

    During the last decade, improved surgical and anesthetic management, such as better understanding of coagulation defects and the use of the phlebotomy, has reduced intraoperative blood product transfusions during orthotopic liver transplantation (OLT). The goal of this study was to look at the impact of initial conventional coagulation tests on blood loss and blood product requirement and to evaluate the role of the phlebotomy during liver transplantations. A total of 700 consecutive OLTs were studied. The group of patients was split into two according to the median of starting international normalized ratio to study blood losses and transfusion rate. Logistic regression was used to determine the main predictors of blood loss, intraoperative blood transfusion, and survival. There was no intergroup difference for demographic characteristics. The mean blood loss was 1,184 mL with a median of 920 mL. Overall, 77.4% of the patients did not receive any blood product and the mean transfusion rate of red blood cells (RBCs) was 0.5 ± 1.4 units per patient. Severity of recipients' disease did not correlate with blood loss or transfusion rate. Starting hemoglobin value was the only biochemical variable linked to RBC transfusions. Phlebotomy was linked to decrease in blood loss, RBC transfusions, and increased survival rate. It is concluded that bleeding did not correlate with traditional coagulation defects or the severity of recipient's disease. Preemptive phlebotomy was linked to a decreased blood loss, a decreased transfusion rate, and an increased 1-year survival rate. PMID:26080304

  16. The influence of joint application of arsenic trioxide and daunorubicin on primary acute promyelocytic leukaemia cells and apoptosis and blood coagulation of cell strain.

    PubMed

    Zhang, Xiaojuan; Qin, Na; Chen, Xinghua; Guo, Shuxia

    2015-05-01

    This test cultivated three groups of acute promyelocytic leukemia (APL) and NB4 cells in liquid in vitro, processed them with arsenic trioxide (ATO), daunorubicin (DNR), ATO+DNR respectively, and then set up blank control group. Apoptosis of cells in each group was observed using flow cytometry, procoagulant activity of APL and NB4 cells in each group was detected with recalcification time, and expressions of tissue factor (TF), thrombomodulin and annexin II of NB4 cells in each group were measured using ELISA method. The results showed that the apoptosis rate increased 4-8 times compared with blank control group after processing APL and NB4 cells with ATO and DNR; procoagulant activity decreased obviously; and expression of TF and annexin II of NB4 cells reduced significantly (P<0.05). We concluded that combination of ATO and DNR could promote APL and NB4 cell apoptosis effectively without aggravating blood coagulation disorders, which might improve coagulation function of APL by inhibiting coagulation and hyperfibrinolysis through reducing expression of TF and annexin II. This drug combination may be a safe and effective method in the treatment of APL of primary high white blood cells type.

  17. Acquired coagulation inhibitor-associated bleeding disorders: an update.

    PubMed

    Franchini, Massimo; Veneri, Dino

    2005-12-01

    Acquired blood coagulation inhibitors are circulating immunoglobulins that neutralize the activity of a specific coagulation protein or accelerate its clearance from the plasma, thus causing a bleeding tendency. In this review, we focus on the nonhemophilic inhibitors of coagulation, i.e. the autoantibodies occurring in individuals without a pre-existent coagulation defect, reporting the most recent advances in the pathophysiology, diagnosis and treatment of these rare acquired bleeding disorders.

  18. Post-traumatic immunosuppression is reversed by anti-coagulated salvaged blood transfusion: deductions from studying immune status after knee arthroplasty

    PubMed Central

    Islam, N; Whitehouse, M; Mehendale, S; Hall, M; Tierney, J; O'Connell, E; Blom, A; Bannister,, G; Hinde, J; Ceredig, R; Bradley, B A

    2014-01-01

    Major trauma increases vulnerability to systemic infections due to poorly defined immunosuppressive mechanisms. It confers no evolutionary advantage. Our objective was to develop better biomarkers of post-traumatic immunosuppression (PTI) and to extend our observation that PTI was reversed by anti-coagulated salvaged blood transfusion, in the knowledge that others have shown that non-anti-coagulated (fibrinolysed) salvaged blood was immunosuppressive. A prospective non-randomized cohort study of patients undergoing primary total knee arthroplasty included 25 who received salvaged blood transfusions collected post-operatively into acid–citrate–dextrose anti-coagulant (ASBT cohort), and 18 non-transfused patients (NSBT cohort). Biomarkers of sterile trauma included haematological values, damage-associated molecular patterns (DAMPs), cytokines and chemokines. Salvaged blood was analysed within 1 and 6 h after commencing collection. Biomarkers were expressed as fold-changes over preoperative values. Certain biomarkers of sterile trauma were common to all 43 patients, including supranormal levels of: interleukin (IL)-6, IL-1-receptor-antagonist, IL-8, heat shock protein-70 and calgranulin-S100-A8/9. Other proinflammatory biomarkers which were subnormal in NSBT became supranormal in ASBT patients, including IL-1β, IL-2, IL-17A, interferon (IFN)-γ, tumour necrosis factor (TNF)-α and annexin-A2. Furthermore, ASBT exhibited subnormal levels of anti-inflammatory biomarkers: IL-4, IL-5, IL-10 and IL-13. Salvaged blood analyses revealed sustained high levels of IL-9, IL-10 and certain DAMPs, including calgranulin-S100-A8/9, alpha-defensin and heat shock proteins 27, 60 and 70. Active synthesis during salvaged blood collection yielded increasingly elevated levels of annexin-A2, IL-1β, Il-1-receptor-antagonist, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IFN-γ, TNF-α, transforming growth factor (TGF)-β1, monocyte chemotactic protein-1 and macrophage inflammatory

  19. Novel pathway of iron‑induced blood coagulation: implications for diabetes mellitus and its complications.

    PubMed

    Lipinski, Boguslaw; Pretorius, Etheresia

    2012-01-01

    Fibrinogen (FBG) is a high-molecular-weight protein and precursor to the enzymatically formed fibrin. It has been recently discovered that FBG can be converted into an insoluble, fibrin-like polymer by a nonenzymatic action of hydroxyl radicals (HRs). These free radicals are generated due to the reaction between hydroxyl groups of water and trivalent ferric ions without the participation of any redox agent. The interaction between HRs and FBG occurs in a purified system, as well as in human plasma and in whole blood. Scanning electron microscopy (SEM) of thrombin-induced fibers and those generated with ferric chloride has shown substantial differences in their morphology and susceptibility to enzymatic degradation. Fibrin strands caused by thrombin are thick and easily digested with chymotrypsin. By contrast, the dense matted deposits formed from FBG in the presence of ferric ions are remarkably resistant to proteolytic and chemical degradations due to the presence of intermolecular hydrophobic bonds. Thus, we postulate that this iron-catalyzed reaction represents a novel blood coagulation pathway operating in degenerative diseases. By means of SEM, we showed the presence of dense fibrin-like deposits in the blood of diabetic patients. Therefore, the prothrombotic state and cardiovascular complications observed in diabetes can be explained in terms of the persistent in vivo action of free iron. This phenomenon may explain hemorheologic disturbances in patients with metabolic syndrome and other diseases caused by iron overload. Of note, HRs can be effectively scavenged by phenolic substances; therefore, certain natural polyphenolic substances, which also scavenge HRs, may be considered to have a potential antidiabetic effect. Moreover, natural or synthetic iron-binding substances may also be considered as a new class of antidiabetic drugs. PMID:22460041

  20. The effect of a new impregnated gauze containing bentonite and halloysite minerals on blood coagulation and wound healing.

    PubMed

    Alavi, Mehrosadat; Totonchi, Alireza; Okhovat, Mohammad Ali; Motazedian, Motahareh; Rezaei, Peyman; Atefi, Mohammad

    2014-12-01

    In recent years, a wide variety of research has been carried out in the field of novel technologies to stop severe bleeding. In several studies, coagulation properties of minerals such as zeolite, bentonite and halloysite have been proven. In this study, the effect of a new impregnated sterile gauze containing bentonite and halloysite minerals was studied on blood coagulation and wound healing rate in male Wistar rats. Initially, impregnated sterile gauze was prepared from the mixture of bentonite and halloysite minerals and petroleum jelly (Vaseline). Then, the effect of gauze was studied on the blood coagulation time and wound healing process in 40 Wistar rats. SPSS software was used for data analysis and P values less than 0.05 were considered significant. The coagulation time of 81.10 ± 2.532 s in the control group and 33.00 ± 1.214 s in the study group (bentonite-halloysite treated) were reported (P < 0.0005). Time for complete wound healing in the group, which is treated with impregnated sterile pads, was calculated approximately from 10 to 12 days. However, in the control group, there was no complete wound healing (P < 0.0005). According to the results of the present study, topical application of the bentonite-halloysite impregnated sterile gauze significantly decreases the clotting time and increase the wound healing rate.

  1. Interference of iron as a coagulant on MIB removal by powdered activated carbon adsorption for low turbidity waters.

    PubMed

    Seckler, Ferreira Filho Sidney; Margarida, Marchetto; Rosemeire, Alves Laganaro

    2013-08-01

    Powered activated carbon (PAC) is widely used in water treatment plants to minimize odors in drinking water. This study investigated the removal of 2-methylisoborneol (MIB) by PAC adsorption, combined with coagulation using iron as a coagulant. The adsorption and coagulation process were studied through different case scenarios of jar tests. The analysis evaluated the effect of PAC dosing in the liquid phase immediately before or after the coagulant addition. Ferric sulphate was used as the coagulant with dosages from 10 to 30 mg/L, and PAC dosages varied from 10 to 40 mg/L. The highest MIB removal efficiency (about 70%) was achieved without the coagulant addition and with the highest PAC dosage (40 mg/L). Lower MIB removal efficiencies were observed in the presence of coagulant, showing a clear interference of the iron precipitate or coagulant in the adsorption process. The degree of interference of the coagulation process in the MIB removal was proportional to the ratio of ferric hydroxide mass to the PAC mass. For both cases of PAC dosing, upstream and downstream of the coagulant injection point, the MIB removal efficiency was similar. However, MIB removal efficiency was 15% lower when compared with experiments without the coagulant application. This interference in the MIB adsorption occurs potentially because the coagulant coats the surface of the carbon and interferes with the MIB coming in contact with the carbon's surface and pores. This constraint requires an increase of the PAC dosage to provide the same efficiency observed without coagulation. PMID:24520695

  2. Ex vivo effects of low-dose rivaroxaban on specific coagulation assays and coagulation factor activities in patients under real life conditions.

    PubMed

    Mani, Helen; Hesse, Christian; Stratmann, Gertrud; Lindhoff-Last, Edelgard

    2013-01-01

    Global coagulation assays display variable effects at different concentrations of rivaroxaban. The aim of this study is to quantify the ex vivo effects of low-dose rivaroxaban on thrombophilia screening assays and coagulation factor activities based on the administration time, and to show how to mask possible interferences. Plasma samples from 40 patients receiving rivaroxaban 10 mg daily were investigated to measure activities of clotting factor II, V, VII, VIII, IX, XI, XII and XIII; protein C- and protein S-levels; lupus anticoagulants; anticardiolipin IgG and IgM; D-dimer, heparin-platelet factor 4 (HPF4) antibodies and screening tests for von Willebrand disease (VWD). Two hours after rivaroxaban administration, the activities of clotting factors were significantly decreased to different extents, except for factor XIII. Dilution of plasma samples resulted in neutralisation of these interferences. The chromogenic protein C activity assay was not affected by rivaroxaban. Depending on the timing of tablet intake in relation to blood sampling protein S activity was measured falsely high when a clotting assay was used. False-positive results for lupus anticoagulants were observed depending on the assay system used and the administration time of rivaroxaban. ELISA-based assays such as anticardiolipin IgG and IgM, D-dimer, HPF4-antibodies and the turbidimetric assays for VWD were not affected by rivaroxaban. Specific haemostasis clotting tests should be performed directly prior to rivaroxaban intake. Assay optimisation in the presence of rivaroxaban can be achieved by plasma dilution. Immunologic assays are not influenced by rivaroxaban, while chromogenic assays can be used, when they do not depend on factor Xa.

  3. Simple and rapid methods for purification and characterization of active coagulants from the seeds of Vigna unguiculata and Parkinsonia aculeata.

    PubMed

    Marobhe, N J; Dalhammar, G; Gunaratna, K R

    2007-06-01

    The coagulating properties of aqueous crude extracts and purified proteins of Vigna unguiculata and Parkinsonia aculeata seeds, which are traditional water coagulants in rural areas of Tanzania, were studied. The coagulation activity assays were done using one millilitre (ml) of kaolin water samples. Coagulating proteins were purified in two-step ion exchange chromatography. The properties of coagulant protein were compared with Moringa oleifera. Coagulating components eluted by 0.6 M NaCl in both coagulants are cationic proteins that have the molecular mass of about 6 kDa, which is very similar to that of M. oleifera. The proteins of V. unguiculata and P. aculeata eluted by 0.3 M NaCl also harbour coagulation activity but proteins eluted with 0.6 M NaCl have higher activity. The dosage for coagulation using purified proteins of both coagulants is about 5 to 10 times lower than that of crude seed extracts. The optimum floc settling time of water treated by crude seed extracts and purified proteins ranged between two and two and half hours. Coagulating proteins of both coagulants eluted by 0.6 M NaCl are thermoresistant and retained coagulation activity of 87% to 92% after boiling for two hours at 80 degrees C and one hour at 95 degrees C. Thermotolerant proteins of V. unguiculata eluted by 0.6 M NaCl and P. aculeata have wider pH range of 5.5 to 8.5 for coagulation activity than those of M. oleifera proteins. The present investigation reveals the possibility of using purified natural coagulants for water treatment to produce safe drinking water.

  4. Massive exploration of perturbed conditions of the blood coagulation cascade through GPU parallelization.

    PubMed

    Cazzaniga, Paolo; Nobile, Marco S; Besozzi, Daniela; Bellini, Matteo; Mauri, Giancarlo

    2014-01-01

    The introduction of general-purpose Graphics Processing Units (GPUs) is boosting scientific applications in Bioinformatics, Systems Biology, and Computational Biology. In these fields, the use of high-performance computing solutions is motivated by the need of performing large numbers of in silico analysis to study the behavior of biological systems in different conditions, which necessitate a computing power that usually overtakes the capability of standard desktop computers. In this work we present coagSODA, a CUDA-powered computational tool that was purposely developed for the analysis of a large mechanistic model of the blood coagulation cascade (BCC), defined according to both mass-action kinetics and Hill functions. coagSODA allows the execution of parallel simulations of the dynamics of the BCC by automatically deriving the system of ordinary differential equations and then exploiting the numerical integration algorithm LSODA. We present the biological results achieved with a massive exploration of perturbed conditions of the BCC, carried out with one-dimensional and bi-dimensional parameter sweep analysis, and show that GPU-accelerated parallel simulations of this model can increase the computational performances up to a 181× speedup compared to the corresponding sequential simulations.

  5. Massive Exploration of Perturbed Conditions of the Blood Coagulation Cascade through GPU Parallelization

    PubMed Central

    Cazzaniga, Paolo; Nobile, Marco S.; Besozzi, Daniela; Bellini, Matteo; Mauri, Giancarlo

    2014-01-01

    The introduction of general-purpose Graphics Processing Units (GPUs) is boosting scientific applications in Bioinformatics, Systems Biology, and Computational Biology. In these fields, the use of high-performance computing solutions is motivated by the need of performing large numbers of in silico analysis to study the behavior of biological systems in different conditions, which necessitate a computing power that usually overtakes the capability of standard desktop computers. In this work we present coagSODA, a CUDA-powered computational tool that was purposely developed for the analysis of a large mechanistic model of the blood coagulation cascade (BCC), defined according to both mass-action kinetics and Hill functions. coagSODA allows the execution of parallel simulations of the dynamics of the BCC by automatically deriving the system of ordinary differential equations and then exploiting the numerical integration algorithm LSODA. We present the biological results achieved with a massive exploration of perturbed conditions of the BCC, carried out with one-dimensional and bi-dimensional parameter sweep analysis, and show that GPU-accelerated parallel simulations of this model can increase the computational performances up to a 181× speedup compared to the corresponding sequential simulations. PMID:25025072

  6. [The pathogenesis of subclinical laminitis in dairy cattle: studies of the hoof status, rumen status and blood coagulation factors].

    PubMed

    Brandejsky, F; Stanek, C; Schuh, M

    1994-02-01

    In 50 dairy cows of the breed "Braunvieh" (36 heifers, 14 cows) of one herd the claw score was recorded over a period of 2 months before parturition until 6 months after parturition. The claw scores were correlated with the clinical findings, the ruminal function and the blood coagulation factors calcium-thromboplastin (TPZ), partial thromboplastin time (PTT), thrombin time (TZ) and antithrombin III (AT III) evaluated one day and one week after calving. The claw score increased from the first to the second examination, remaining on the same level in the postpartal period. No correlation between the claw scores and the ruminal function was evident. In comparison with a control group, TPZ and PTT were found higher one day and one week after parturition in the experimental group. Blood coagulation factors and claw scores were found uncorrelated.

  7. Methodical aspects of blood coagulation measurements in birds applying commercial reagents--a pilot study.

    PubMed

    Guddorf, Vanessa; Kummerfeld, Norbert; Mischke, Reinhard

    2014-01-01

    The aim of this study was to examine the suitability of commercially available reagents for measurements of coagulation parameters in citrated plasma from birds. Therefore, plasma samples of 17 healthy donor birds of different species were used to determine prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) applying various commercial reagents which are routinely used in coagulation diagnostics in humans and mammals. A PT reagent based on human placental thromboplastin yielded not only shorter clotting times than a reagent containing recombinant human tissue factor (median 49 vs. 84 s), but also showed a minor range of distribution of values (43-55 s vs. 30-147 s, minimum-maximum, n = 5 turkeys). An aPTT reagent containing kaolin and phospholipids of animal origin delivered the shortest clotting times and the lowest range of variation in comparison to three other reagents of different composition. However, even when this reagent was used, aPTTs were partially extremely long (> 200 s). Thrombin time was 38 s (28-57 s, n = 5 chicken) when measured with bovine thrombin at a final concentration of 2 IU thrombin/ ml. Coefficients of variation for within-run precision analysis (20 repetitions) of PT was 8.0% and 4.7% for aPTT measurements using selected reagents of mammalian origin. In conclusion, of the commercially available reagents tested, a PT reagent based on human placental thromboplastin and an aPTT reagent including rabbit brain phospholipid and kaolin, show some promise for potential use in birds.

  8. Requirements for Receptor Engagement during Infection by Adenovirus Complexed with Blood Coagulation Factor X

    PubMed Central

    Bradshaw, Angela C.; Parker, Alan L.; Duffy, Margaret R.; Coughlan, Lynda; van Rooijen, Nico; Kähäri, Veli-Matti; Nicklin, Stuart A.; Baker, Andrew H.

    2010-01-01

    Human adenoviruses from multiple species bind to coagulation factor X (FX), yet the importance of this interaction in adenovirus dissemination is unknown. Upon contact with blood, vectors based on adenovirus serotype 5 (Ad5) binds to FX via the hexon protein with nanomolar affinity, leading to selective uptake of the complex into the liver and spleen. The Ad5:FX complex putatively targets heparan sulfate proteoglycans (HSPGs). The aim of this study was to elucidate the specific requirements for Ad5:FX-mediated cellular uptake in this high-affinity pathway, specifically the HSPG receptor requirements as well as the role of penton base-mediated integrin engagement in subsequent internalisation. Removal of HS sidechains by enzymatic digestion or competition with highly-sulfated heparins/heparan sulfates significantly decreased FX-mediated Ad5 cell binding in vitro and ex vivo. Removal of N-linked and, in particular, O-linked sulfate groups significantly attenuated the inhibitory capabilities of heparin, while the chemical inhibition of endogenous HSPG sulfation dose-dependently reduced FX-mediated Ad5 cellular uptake. Unlike native heparin, modified heparins lacking O- or N-linked sulfate groups were unable to inhibit Ad5 accumulation in the liver 1h after intravascular administration of adenovirus. Similar results were observed in vitro using Ad5 vectors possessing mutations ablating CAR- and/or αv integrin binding, demonstrating that attachment of the Ad5:FX complex to the cell surface involves HSPG sulfation. Interestingly, Ad5 vectors ablated for αv integrin binding showed markedly delayed cell entry, highlighting the need for an efficient post-attachment internalisation signal for optimal Ad5 uptake and transport following surface binding mediated through FX. This study therefore integrates the established model of αv integrin-dependent adenoviral infection with the high-affinity FX-mediated pathway. This has important implications for mechanisms that define

  9. Moojenactivase, a novel pro-coagulant PIIId metalloprotease isolated from Bothrops moojeni snake venom, activates coagulation factors II and X and induces tissue factor up-regulation in leukocytes.

    PubMed

    Sartim, Marco A; Costa, Tassia R; Laure, Helen J; Espíndola, Milena S; Frantz, Fabiani G; Sorgi, Carlos A; Cintra, Adélia C O; Arantes, Eliane C; Faccioli, Lucia H; Rosa, José C; Sampaio, Suely V

    2016-05-01

    Coagulopathies following snakebite are triggered by pro-coagulant venom toxins, in which metalloproteases play a major role in envenomation-induced coagulation disorders by acting on coagulation cascade, platelet function and fibrinolysis. Considering this relevance, here we describe the isolation and biochemical characterization of moojenactivase (MooA), a metalloprotease from Bothrops moojeni snake venom, and investigate its involvement in hemostasis in vitro. MooA is a glycoprotein of 85,746.22 Da, member of the PIIId group of snake venom metalloproteases, composed of three linked disulfide-bonded chains: an N-glycosylated heavy chain, and two light chains. The venom protease induced human plasma clotting in vitro by activating on both blood coagulation factors II (prothrombin) and X, which in turn generated α-thrombin and factor Xa, respectively. Additionally, MooA induced expression of tissue factor (TF) on the membrane surface of peripheral blood mononuclear cells (PBMC), which led these cells to adopt pro-coagulant characteristics. MooA was also shown to be involved with production of the inflammatory mediators TNF-α, IL-8 and MCP-1, suggesting an association between MooA pro-inflammatory stimulation of PBMC and TF up-regulation. We also observed aggregation of washed platelets when in presence of MooA; however, the protease had no effect on fibrinolysis. Our findings show that MooA is a novel hemostatically active metalloprotease, which may lead to the development of coagulopathies during B. moojeni envenomation. Moreover, the metalloprotease may contribute to the development of new diagnostic tools and pharmacological approaches applied to hemostatic disorders. PMID:26026608

  10. Influence of red blood cell concentration on the initiation time of blood coagulation: risk of thrombus formation in pregnant females with anemia.

    PubMed

    Sagesaka, Toshiaki; Juen, Hiroyasu; Hayashi, Masatoshi

    2007-01-01

    The influence of a change in red blood cell (RBC) concentration on the initiation time of blood coagulation (Ti) in pregnant and non-pregnant females was investigated using a damped oscillation rheometer to evaluate the risk of hemorrhagic tendency or thrombus formation. The blood samples from 40 female volunteers (20 pregnants and 20 non-pregnants) were examined. After centrifuging some portion of each blood sample, an appropriate volume was taken from the RBC layer to make an artificially diluted blood, or to add it to the autologous blood, making an artificially concentrated blood. The Ti of non-pregnant females was significantly reduced with increasing the RBC concentration from 3.75+/-0.25 to (5.75+/-0.25)x10(6)/mm(3). However, the Ti of pregnant females showed almost no change in the RBC concentrations from 3.25+/-0.25 to (5.25+/-0.25)x10(6)/mm(3). These results suggest that RBC concentration plays an important role in accelerating the initial coagulation reaction of blood of non-pregnant females and that a hypercoagulant condition caused by pregnancy conceals the effect that changes in RBC concentration have in pregnant females. PMID:17325439

  11. Polyphenol compounds belonging to flavonoids inhibit activity of coagulation factor X.

    PubMed

    Bijak, Michal; Ponczek, Michal Blazej; Nowak, Pawel

    2014-04-01

    Blood coagulation consists of series of zymogens which can be converted by limited proteolysis to active enzymes leading to the generation of thrombin and conversion of fibrinogen into fibrin by this enzyme. The activated factor X (FXa) forms prothrombinase complex on phosphatidylserine containing surface which is responsible for conversion of prothrombin to thrombin. One molecule of FXa generates more than 1000 thrombin molecules. Therefore FXa is a novel target for modern anticoagulant therapy. The aim of our present study is to examine the effects of the well-known plant polyphenolic compounds on factor Xa amidolytic activity and characterization of these interactions using bioinformatic ligand docking method. We observed that only four polyphenols belonging to flavonoids group: procyanidin B2, cyanidin, quercetin and silybin, had inhibitory effect on FXa activity. Bioinformatic analyses revealed that procyanidin B2, cyanidin, quercetin and silybin bound in the S1-S4 pockets located in vicinity of the FXa active site and blocked access of substrates to Ser195. The results presented here showed that flavonoids might be potential structural bases for design of new nature-based, safe, orally bioavailable direct FXa inhibitors. PMID:24444877

  12. Effects of Blood Coagulate Removal Method on Aedes albopictus (Diptera: Culicidae) Life Table Characteristics and Vector Competence for Dengue Virus.

    PubMed

    van Dodewaard, Caitlin A M; Richards, Stephanie L; Harris, Jonathan W

    2016-01-01

    Commercially available blood can be used as an alternative to live animals to maintain mosquito colonies and deliver infectious bloodmeals during research studies. We analyzed the extent to which two methods for blood coagulate removal (defibrination or addition of sodium citrate) affected life table characteristics (i.e., fecundity, fertility, hatch rate, and adult survival) and vector competence (infection, dissemination, and transmission) of Aedes albopictus (Skuse) for dengue virus (DENV). Two types of bovine blood were tested at two extrinsic incubation temperatures (27 or 30°C) for DENV-infected and uninfected mosquitoes. Fully engorged mosquitoes were transferred to individual cages containing an oviposition cup and a substrate. Eggs (fecundity) and hatched larvae (fertility) were counted. At 14 and 21 d post feeding on a DENV-infected bloodmeal, 15 mosquitoes were sampled from each group, and vector competence was analyzed (bodies [infection], legs [dissemination], and saliva [transmission]). Differences in life table characteristics and vector competence were analyzed for mosquitoes fed blood processed using different methods for removal of coagulates. The method for removal of coagulates significantly impacted fecundity, fertility, and hatch time in the uninfected group, but not DENV-infected group. Infected mosquitoes showed significantly higher fecundity and faster hatch time than uninfected mosquitoes. We show no significant differences in infection or dissemination rates between groups; however, horizontal transmission rate was significantly higher in mosquitoes fed DENV-infected citrated compared with defibrinated blood. We expect the findings of this study to inform research using artificial blood delivery methods to assess vector competence.

  13. Spatial aspects of blood coagulation: two decades of research on the self-sustained traveling wave of thrombin.

    PubMed

    Guria, Konstantin; Guria, Georgy Th

    2015-03-01

    In a number of experimental studies, it has been demonstrated that the forefront of blood coagulation can propagate in the manner of a signal relay. These data strongly support the concept that the formation of a blood clot is governed by a self-sustained traveling wave of thrombin. The present review critically appraises the experimental data obtained in recent decades concerning the self-sustained spatial propagation of thrombin. Open questions regarding the experimental detection of the self-sustained propagation of thrombin are discussed.

  14. The Mechanisms of Coagulation.

    ERIC Educational Resources Information Center

    Kurtz, Richard; Jesty, Jolyon

    1994-01-01

    Several topics such as heart disease, strokes, biochemical reactions, blood components, and genetics can be related to blood clotting. Introduces a simple, safe and inexpensive hands-on demonstration using bovine (cattle) blood plasma of normal and abnormal coagulation. (ZWH)

  15. TREATMENT OF LANDFILL LEACHATE BY COUPLING COAGULATION-FLOCCULATION OR OZONATION TO GRANULAR ACTIVATED CARBON ADSORPTION.

    PubMed

    Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H

    2015-01-01

    A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation. PMID:26630756

  16. TREATMENT OF LANDFILL LEACHATE BY COUPLING COAGULATION-FLOCCULATION OR OZONATION TO GRANULAR ACTIVATED CARBON ADSORPTION.

    PubMed

    Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H

    2015-01-01

    A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation.

  17. Platelet Surface-Associated Activation and Secretion-Mediated Inhibition of Coagulation Factor XII

    PubMed Central

    Zakharova, Natalia V.; Artemenko, Elena O.; Podoplelova, Nadezhda A.; Sveshnikova, Anastasia N.; Demina, Irina A.; Ataullakhanov, Fazly I.; Panteleev, Mikhail A.

    2015-01-01

    Coagulation factor XII (fXII) is important for arterial thrombosis, but its physiological activation mechanisms are unclear. In this study, we elucidated the role of platelets and platelet-derived material in fXII activation. FXII activation was only observed upon potent platelet stimulation (with thrombin, collagen-related peptide, or calcium ionophore, but not ADP) accompanied by phosphatidylserine exposure and was localised to the platelet surface. Platelets from three patients with grey platelet syndrome did not activate fXII, which suggests that platelet-associated fXII-activating material might be released from α-granules. FXII was preferentially bound by phosphotidylserine-positive platelets and annexin V abrogated platelet-dependent fXII activation; however, artificial phosphotidylserine/phosphatidylcholine microvesicles did not support fXII activation under the conditions herein. Confocal microscopy using DAPI as a poly-phosphate marker did not reveal poly-phosphates associated with an activated platelet surface. Experimental data for fXII activation indicates an auto-inhibition mechanism (ki/ka = 180 molecules/platelet). Unlike surface-associated fXII activation, platelet secretion inhibited activated fXII (fXIIa), particularly due to a released C1-inhibitor. Platelet surface-associated fXIIa formation triggered contact pathway-dependent clotting in recalcified plasma. Computer modelling suggests that fXIIa inactivation was greatly decreased in thrombi under high blood flow due to inhibitor washout. Combined, the surface-associated fXII activation and its inhibition in solution herein may be regarded as a flow-sensitive regulator that can shift the balance between surface-associated clotting and plasma-dependent inhibition, which may explain the role of fXII at high shear and why fXII is important for thrombosis but negligible in haemostasis. PMID:25688860

  18. The structures of the carbohydrate moieties of bovine blood coagulation factor IX (Christmas factor).

    PubMed

    Mizuochi, T; Taniguchi, T; Fujikawa, K; Titani, K; Kobata, A

    1983-05-25

    Bovine blood coagulation factor IX (Christmas factor) contains four asparagine-linked sugar chains in one molecule. The sugar chains were quantitatively liberated as radioactive oligosaccharides from the polypeptide moiety by hydrazinolysis followed by N-acetylation and NaB3H4 reduction. The structures of these sugar chains were determined by sequential exoglycosidase digestion in combination with methylation analysis. Bovine factor IX contained two unique penta- and tetrasialyl triantennary sugar chains with the structures shown below in addition to tetra-, tri-, and disialyl biantennary sugar chains of Sia alpha 2 leads to 3 Gal beta 1 leads 3(Sia alpha 2 leads to 6)GlcNAc beta 1 leads to 2Man alpha 1 leads to 6[Sia alpha 2 leads to 3Gal beta 1 leads to 3(Sia alpha 2 leads to 6)GlcNac beta 1 leads to 2Man alpha 1 leads to 3]Man beta 1 leads to 4GlcNAc beta 1 leads to 4GlcNAc, Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6[Sia alpha 2 leads to 3Gal beta 1 leads to 3(Sia alpha 2 leads to 6)GlcNAc beta 1 leads to 2Man alpha 1 leads to 3]Man beta 1 leads to 4GlcNAc beta 1 leads to 4GlcNAc, and Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GlcNAc beta 1 leads to 4GlcNAc and their partially desialized forms.

  19. [Samples in Coagulation Test].

    PubMed

    Komiyama, Yutaka

    2015-12-01

    An understanding and ability to develop a strategy to prevent pre-analytical errors of laboratory tests in the hemostasis area are two of the most important skills of medical technologists and related doctors. Recently, the working group for standardization of sampling in coagulation tests is working towards a consensus. This article reviews a summary of the consensus: (1) The anticoagulant for coagulation tests is 3.13-3.2% sodium citrate at a ratio of 1:9 to whole blood and the accuracy of the ratio is within 10%. (2) Blood sampling is achieved with the use of a 21-23G needle and coagulation. Blood sampling can be achieved by both a syringe and vacuum tube system. After taking blood, laboratory tests such as of the prothrombin time (PT) and activated partial thromboplastin time (APTT) should be completed within one hour and the storage temperature should be at room temperature, not ice-cold conditions. 3) To prepare a plasma sample, citrated blood is centrifuged at 1,500 x g for 15 min at room temperature to minimize the remaining platelets in plasma (below 10,000/microL at least).

  20. Comparison of the level of residual coagulant activity in different cheese varieties.

    PubMed

    Bansal, Nidhi; Fox, Patrick F; McSweeney, Paul L H

    2009-08-01

    The coagulant retained in cheese curd is a major contributor to proteolysis during ripening. The objective of this study was to quantify residual coagulant in 9 cheese varieties by measuring its activity on a synthetic heptapeptide (Pro-Thr-Glu-Phe-[NO2-Phe]-Arg-Leu) assayed using reversed-phase HPLC. The level of residual coagulant activity was highest in Camembert cheese, probably due to its low pH at whey drainage and the high moisture content of the cheese, followed in order by Feta=Port du Salut=Cheddar>Gouda>Emmental=Parmigiano Reggiano=low-moisture part-skim Mozzarella=Mozzarella di Bufala Campana. The high cooking temperature (50-54 degrees C) used during the manufacture of Emmental and Parmigiano Reggiano cheeses and the cooking and stretching step in hot water during the manufacture of Mozzarella cheese may be the reasons for the lowest residual coagulant activity in these cheeses. The level of residual coagulant activity was higher in Feta cheese made from milk concentrated by ultrafiltration than in conventional Feta.

  1. [In vitro effects of hemocoagulase atrix and its effective components on blood coagulation of patients with bleeding disorders].

    PubMed

    Wang, Rui-Juan; Wang, Zhao-Yue; Jiang, Ming-Hua; Zhang, Wei; Cao, Li-Juan; Sun, Xiong-Hua; Zhang, Jian; Bai, Xia; Ruan, Chang-Geng

    2012-04-01

    This study was aimed to investigate the pro coagulation effects of hemocoagulase atrix and its effective components (batroxobin and factor X activator) on plasma of normal subjects and patients with bleeding disorders and their mechanisms. Activated partial thromboplastin time (APTT) and prothrombin time (PT) were measured. The factor (F)X activation and thrombin generation were analyzed by using chromogenic substrate method. The results showed that the plasma APTT of normal subjects was shortened by hemocoagulase atrix, batroxobin and FX activator, and the effect of FX activator was found to be concentration-dependent (r = 0.889, P < 0.05). The prolonged APTT of plasma from patients with bleeding disorders could be corrected by hemocoagulase atrix, batroxobin and FX activator, but PT showed no great changes resulted from the treatments. FX activator could promote FX activation and thrombin generation, while neither hemocoagulase atrix nor batroxobin showed such abilities. It is concluded that hemocoagulase atrix promotes coagulation process, and corrects coagulation abnormalities in patients with bleeding disorders, its main component batroxobin directly acts on fibrinogen, and FX activator promotes thrombin generation through activating FX.

  2. Safety of plasma-derived protein C for treating disseminated intravascular coagulation in adult patients with active cancer.

    PubMed

    Malato, Alessandra; Saccullo, Giorgia; Coco, Lucio Lo; Caracciolo, Clementina; Raso, Simona; Santoro, Marco; Zammit, Valentina; Siragusa, Sergio

    2012-02-01

    Cancer-related disseminated intravascular coagulation (DIC) is a life-threatening condition for which no effective treatment is currently available. Protein C (PC), a modulator of coagulation as well as the inflammatory system, has been successfully tested (in its activated recombinant form [a-rPC]) in sepsis-related coagulopathy, but with an increased risk for major bleeding. Plasma-derived PC (pd-PC) is more suitable than a-rPC in patients at high risk from bleeding due to its self-limiting process. We carried out a single-arm study evaluating the role of pd-PC in adult cancer patients with overt DIC. Over a period of 3 years, we treated 19 patients with overt DIC and a PC plasma concentration <50%; all received PC concentrate (Ceprotin(®), Baxter) for 72 hr in adjusted doses to restore normal PC values (70-120%). Blood coagulation, haematological tests, and the DIC score were recorded after 12, 24, 48 hr, 7 and 10 days, while clinical outcomes (bleeding, thrombosis and mortality) were recorded up to 28 days. Within 48 hr of starting pd-PC therapy, laboratory tests as well as the DIC score improved in all patients. At 28-days follow-up, no bleeding or thrombosis was observed. This is the first study to investigate the use of pd- PC for treatment of cancer-related overt DIC.

  3. Complete treatment of olive pomace leachate by coagulation, activated-carbon adsorption and electrochemical oxidation.

    PubMed

    Mavros, Michael; Xekoukoulotakis, Nikolaos P; Mantzavinos, Dionissios; Diamadopoulos, Evan

    2008-06-01

    A battery scheme comprising sequential alum coagulation, activated-carbon adsorption and electrochemical oxidation over boron-doped diamond electrodes to mineralize a leachate from olive pomace processing is demonstrated. The effect of coagulant and adsorbent concentration on treatment efficiency was assessed in the range 0.1-50 mM Al(3+) and 2.5-50 g/L activated-carbon and optimal conditions were established. Coagulation at 7.5mM Al(3+) resulted in substantial solids and color removal (i.e. 80% and 93%, respectively). This was accompanied by only 30% chemical oxygen demand (COD) reduction (initial COD was about 3,500 mg/L). The latter increased to 80% though when coagulation was coupled with adsorption at 25 g/L activated carbon. Electrochemical oxidation of the original effluent for 360 min led to 63% and 82% COD reduction at 10 and 20A current intensity, respectively. When this process was tested as a polishing stage following coagulation and adsorption, overall COD removal reached values of 92% and 97%, respectively. The final effluent was also colorless and solids free. However, the treated effluent still exhibited ecotoxicity possibly due to the formation of ecotoxic oxidation products. PMID:18396309

  4. Effect of high pressures on the enzymatic activity of commercial milk protein coagulants

    NASA Astrophysics Data System (ADS)

    Wiśniewska, Krystyna; Reps, Arnold; Jankowska, Agnieszka

    2014-04-01

    This study was aimed at determining the effect of high pressures in the range of 100-1000 MPa/15 min, applied in 100 MPa increments, on the coagulating and proteolytic activity of commercial coagulants produced with genetic engineering methods: Maxiren, Chymogen, Chymax and of a natural rennin preparation, Hala. The coagulating activity of Hala preparation differed compared with the other preparations, due to greater resistance to high pressures, especially in the range of 500-600 MPa. The preparations produced with genetic engineering methods lost their capability for milk protein coagulation by 500 MPa. Pressurization at 200 MPa contributed to their reduced capability for casein macroproteolysis. In contrast, an increase in Chymax, Chymogen, Maxiren and Hala preparations' hydrolytic capability for the macroproteolysis of isoelectric casein was observed upon pressure treatment at 100 and 400 MPa and for microproteolysis after pressure treatment at 200 MPa. Storage (48 h/5°C) of the pressurized preparations had an insignificant effect on their coagulating and proteolytic activities.

  5. A comparative treatment of stabilized landfill leachate: coagulation and activated carbon adsorption vs. electrochemical oxidation.

    PubMed

    Papastavrou, Chrystalla; Mantzavinos, Dionissios; Diamadopoulos, Evan

    2009-12-14

    This work investigated the treatment of a landfill leachate that had previously undergone biological treatment. Two treatment schemes were compared: the first one involved coagulation followed by activated carbon adsorption, whilst the second was electrochemical treatment. Coagulation with alum resulted in a 50% removal of chemical oxygen demand (COD). The optimum aluminium dose was 3 mM Al3+. Activated carbon adsorption of stabilized leachate that had been previously treated by coagulation resulted in an overall 80% removal of COD. However, a significant part of the organic matter (corresponding to 170 mg/L) was non-adsorbable. Electrochemical oxidation over a boron-doped diamond electrode led to about 90% COD removal in 240 min with the resulting stream having a COD content as low as 50 mg/L. An increase in current intensity from 15 A to 21 A had no practical effect on the overall COD removal, which followed first-order kinetics. PMID:20183999

  6. Long-term Exposure to Air Pollution and Markers of Inflammation, Coagulation, and Endothelial Activation

    PubMed Central

    Hajat, Anjum; Allison, Matthew; Diez-Roux, Ana V.; Jenny, Nancy Swords; Jorgensen, Neal W.; Szpiro, Adam A.; Vedal, Sverre; Kaufman, Joel D.

    2015-01-01

    Background Air pollution is associated with cardiovascular disease, and systemic inflammation may mediate this effect. We assessed associations between long- and short-term concentrations of air pollution and markers of inflammation, coagulation, and endothelial activation. Methods We studied participants from the Multi-Ethnic Study of Atherosclerosis from 2000 to 2012 with repeat measures of serum C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, D-dimer, soluble E-selectin, and soluble Intercellular Adhesion Molecule-1. Annual average concentrations of ambient fine particulate matter (PM2.5), individual-level ambient PM2.5 (integrating indoor concentrations and time–location data), oxides of nitrogen (NOx), nitrogen dioxide (NO2), and black carbon were evaluated. Short-term concentrations of PM2.5 reflected the day of blood draw, day prior, and averages of prior 2-, 3-, 4-, and 5-day periods. Random-effects models were used for long-term exposures and fixed effects for short-term exposures. The sample size was between 9,000 and 10,000 observations for CRP, IL-6, fibrinogen, and D-dimer; approximately 2,100 for E-selectin; and 3,300 for soluble Intercellular Adhesion Molecule-1. Results After controlling for confounders, 5 µg/m3 increase in long-term ambient PM2.5 was associated with 6% higher IL-6 (95% confidence interval = 2%, 9%), and 40 parts per billion increase in long-term NOx was associated with 7% (95% confidence interval = 2%, 13%) higher level of D-dimer. PM2.5 measured at day of blood draw was associated with CRP, fibrinogen, and E-selectin. There were no other positive associations between blood markers and short- or long-term air pollution. Conclusions These data are consistent with the hypothesis that long-term exposure to air pollution is related to some markers of inflammation and fibrinolysis. PMID:25710246

  7. A novel μ-fluidic whole blood coagulation assay based on Rayleigh surface-acoustic waves as a point-of-care method to detect anticoagulants

    PubMed Central

    Meyer dos Santos, Sascha; Zorn, Anita; Guttenberg, Zeno; Picard-Willems, Bettina; Kläffling, Christina; Nelson, Karen; Klinkhardt, Ute; Harder, Sebastian

    2013-01-01

    A universal coagulation test that reliably detects prolonged coagulation time in patients, irrespective of the anticoagulant administered, has not been available to date. An easily miniaturised, novel μ-fluidic universal coagulation test employing surface acoustic waves (SAW) is presented here. SAW was employed to instantly mix and recalcify 6 μl citrated whole blood and image correlation analysis was used to quantify clot formation kinetics. The detection of clinically relevant anticoagulant dosing with old anticoagulants (unfractionated heparin, argatroban) and new anticoagulants (dabigatran, rivaroxaban) has been tested and compared to standard plasma coagulation assays. The applicability of this novel method has been confirmed in a small patient population. Coagulation was dose-proportionally prolonged with heparin, argatroban, dabigatran, and rivaroxaban, comparable to standard tests. Aspirin and clopidogrel did not interfere with the SAW-induced clotting time (SAW-CT), whereas the strong GPIIb/IIIa-inhibitor abciximab did interfere. Preliminary clinical data prove the suitability of the SAW-CT in patients being treated with warfarin, rivaroxaban, or dabigatran. The system principally allows assessment of whole blood coagulation in humans in a point-of-care setting. This method could be used in stroke units, emergency vehicles, general and intensive care wards, as well as for laboratory and home testing of coagulation. PMID:24404078

  8. Synergistic effect of biological activated carbon and enhanced coagulation in secondary wastewater effluent treatment.

    PubMed

    Aryal, A; Sathasivan, A; Vigneswaran, S

    2012-01-01

    The use of secondary wastewater effluent (SWWE) is an essential strategy for making better use of limited water resources. However, a wide range of organic compounds eventually renders them unsuitable for recycling. In water treatment processes, biologically activated carbon (BAC) is adopted after physicochemical treatment. However, the effectiveness of such combination for SWWE remains poorly understood. This study investigates the effectiveness of various combinations: BAC/enhanced coagulation (EC) or EC/BAC, especially in terms of dissolved organic carbon (DOC) removal. The results showed that distinct advantage could be obtained by adopting BAC/EC combination rather than EC/BAC, as microbes in BAC not only remove non-coagulable compounds but also synergize the removal efficiency by releasing some coagulable humic substances.

  9. Interleukin-2 induces activation of coagulation and fibrinolysis: resemblance to the changes seen during experimental endotoxaemia.

    PubMed

    Baars, J W; de Boer, J P; Wagstaff, J; Roem, D; Eerenberg-Belmer, A J; Nauta, J; Pinedo, H M; Hack, C E

    1992-10-01

    The administration of Interleukin-2 (IL-2) causes the release or generation of other cytokines such as tumour necrosis factor (TNF) which, by disturbing the anticoagulant properties of the endothelium, may induce a procoagulant state in patients receiving this drug. We therefore evaluated the effects of IL-2 on coagulation and fibrinolysis in 14 patients receiving 12 or 18 x 10(6) IU/m2/d of IL-2 given as a 15 min infusion for 5 d. Blood samples were drawn at short intervals after the first IL-2 infusion. The parameters were analysed by way of analysis for repeated measures (F tests rather than t tests). During the first day, thrombin-antithrombin (TAT) complexes started to increase 2 h after the IL-2 infusion, reaching peak levels at 4 h (n = 14; 11.2 +/- 6.4 micrograms/l v 49.8 +/- 49.2 micrograms/l, P < 0.01). Plasma alpha 2 antiplasmin (PAP) complexes showed a similar pattern rising from a mean baseline value of 17.5 +/- 7.6 nmol/l to 66.8 +/- 47.7 nmol at 4 h (P < 0.01). In four patients the peak of PAP preceeded that of TAT. Tissue plasminogen activator (tPA) rose from a mean baseline value of 4.9 +/- 3.7 micrograms/l to 26.3 +/- 13.5 micrograms/l at 4 h (P < 0.01). Plasminogen-activator-inhibitor-1 (PAI-1) levels increased from 59 +/- 35 micrograms/l to 113 +/- 39 micrograms/l at 6 h (P < 0.01). tPA PAI-1 complexes increased from 0.15 +/- 0.07 to 0.69 +/- 0.21 nmol/l at 6 h (P < 0.01). Our study indicates that IL-2 activates the coagulation and fibrinolytic systems in vivo. The changes resemble the perturbations observed after endotoxin/TNF administration. These abnormalities may play a role in the side-effects induced by IL-2 therapy.

  10. Tumour sublines with different metastatic capacity induce similar blood coagulation changes in the host.

    PubMed Central

    Delaini, F.; Giavazzi, R.; De Bellis Vitti, G.; Alessandri, G.; Mantovani, A.; Donati, M. B.

    1981-01-01

    This paper is aimed at investigating how metastatic tumour growth influenced the haemostatic system of the host. Blood platelet count, blood fibrinogen level, the activated partial thromboplastin time (APTT) and the prothrombin time (PT) were determined at various intervals during growth and metastasis of a murine fibrosarcoma (mFS6) or one of its sublines with different metastatic capacity. Progressive thrombocytopenia and increase in fibrinogen level were observed during development of the tumour in all the animal groups studied, irrespective of the metastatic potential of the various sublines. No significant changes were observed in the PT or APTT values. These data support the concept that primary rather than metastatic growth influences the haemostatic system of tumour-bearing animals. PMID:7459231

  11. Changes in blood coagulation induced by exercise training in young athletic horses.

    PubMed

    Assenza, A; Tosto, F; Casella, S; Fazio, F; Giannetto, C; Piccione, G

    2013-12-01

    Prothrombin Time (PT), Activated Partial Prothrombin Time (APTT), Fibrinogen concentration (Fbg) and Platelet number (Plt) were evaluated in 20 young athletic horses during a training program. A standardized exercise test (SET) was performed every month for three months. The V4 variations (the speed, in m/min, reached at the blood lactate concentration of 4 mmol/l) obtained for each test were calculated to assess the effect of training program on athletic performance. Blood samples were collected at 20-day intervals over a period of 80 days from the beginning of the training program. The V4 (P < 0.001), PT (P < 0.001), APTT (P < 0.01), Fbg (P < 0.01) and Plt (P < 0.001) varied throughout the training period showing that the modifications of clotting mechanism in response to training period may be considered as a normal physiological response of the hemostatic system to training exercise.

  12. Positive selection during the evolution of the blood coagulation factors in the context of their disease-causing mutations.

    PubMed

    Rallapalli, Pavithra M; Orengo, Christine A; Studer, Romain A; Perkins, Stephen J

    2014-11-01

    Blood coagulation occurs through a cascade of enzymes and cofactors that produces a fibrin clot, while otherwise maintaining hemostasis. The 11 human coagulation factors (FG, FII-FXIII) have been identified across all vertebrates, suggesting that they emerged with the first vertebrates around 500 Ma. Human FVIII, FIX, and FXI are associated with thousands of disease-causing mutations. Here, we evaluated the strength of selective pressures on the 14 genes coding for the 11 factors during vertebrate evolution, and compared these with human mutations in FVIII, FIX, and FXI. Positive selection was identified for fibrinogen (FG), FIII, FVIII, FIX, and FX in the mammalian Primates and Laurasiatheria and the Sauropsida (reptiles and birds). This showed that the coagulation system in vertebrates was under strong selective pressures, perhaps to adapt against blood-invading pathogens. The comparison of these results with disease-causing mutations reported in FVIII, FIX, and FXI showed that the number of disease-causing mutations, and the probability of positive selection were inversely related to each other. It was concluded that when a site was under positive selection, it was less likely to be associated with disease-causing mutations. In contrast, sites under negative selection were more likely to be associated with disease-causing mutations and be destabilizing. A residue-by-residue comparison of the FVIII, FIX, and FXI sequence alignments confirmed this. This improved understanding of evolutionary changes in FVIII, FIX, and FXI provided greater insight into disease-causing mutations, and better assessments of the codon sites that may be mutated in applications of gene therapy.

  13. Positive Selection during the Evolution of the Blood Coagulation Factors in the Context of Their Disease-Causing Mutations

    PubMed Central

    Rallapalli, Pavithra M.; Orengo, Christine A.; Studer, Romain A.; Perkins, Stephen J.

    2014-01-01

    Blood coagulation occurs through a cascade of enzymes and cofactors that produces a fibrin clot, while otherwise maintaining hemostasis. The 11 human coagulation factors (FG, FII–FXIII) have been identified across all vertebrates, suggesting that they emerged with the first vertebrates around 500 Ma. Human FVIII, FIX, and FXI are associated with thousands of disease-causing mutations. Here, we evaluated the strength of selective pressures on the 14 genes coding for the 11 factors during vertebrate evolution, and compared these with human mutations in FVIII, FIX, and FXI. Positive selection was identified for fibrinogen (FG), FIII, FVIII, FIX, and FX in the mammalian Primates and Laurasiatheria and the Sauropsida (reptiles and birds). This showed that the coagulation system in vertebrates was under strong selective pressures, perhaps to adapt against blood-invading pathogens. The comparison of these results with disease-causing mutations reported in FVIII, FIX, and FXI showed that the number of disease-causing mutations, and the probability of positive selection were inversely related to each other. It was concluded that when a site was under positive selection, it was less likely to be associated with disease-causing mutations. In contrast, sites under negative selection were more likely to be associated with disease-causing mutations and be destabilizing. A residue-by-residue comparison of the FVIII, FIX, and FXI sequence alignments confirmed this. This improved understanding of evolutionary changes in FVIII, FIX, and FXI provided greater insight into disease-causing mutations, and better assessments of the codon sites that may be mutated in applications of gene therapy. PMID:25158795

  14. Long-term activation of the pro-coagulant response after neoadjuvant chemoradiation and major cancer surgery

    PubMed Central

    Byrne, M; Reynolds, J V; O'Donnell, J S; Keogan, M; White, B; Byrne, M; Murphy, S; Maher, S G; Pidgeon, G P

    2009-01-01

    Background: The association between cancer, major surgery and venous thromboembolism (VTE) is well established. Multimodal therapy is increasingly being used as standard treatment for localised gastrointestinal cancer. The aim of this study was to examine the markers of pro-coagulation response and VTE risk in an exemplar multimodal model of pre-operative combination chemotherapy and radiation therapy, followed by complex cancer surgery. Methods: Consecutive patients (n=36) with localised oesophageal cancer were studied at baseline after the first and second cycles of chemoradiation, and on post-operative days 1–28, and at 3, 6 and 9 months. Factors regulating the pro- and anti-coagulant response, as well as pro-inflammatory markers including NFκB activation in peripheral blood mononuclear cells, were examined. All patients received enoxaparin 40 mg s.c. postoperatively up to discharge, and underwent pulmonary CT-pulmonary angiography and venography on day 10 postoperatively. Results: Four (11%) non-fatal thromboembolic events were documented, all after hospital discharge. Neoadjuvant therapy before surgery activated factor VIII (FVIII) and pro-inflammatory NFκB, and increased D-dimers, pro-thrombin fragment 1+2 (F1+2) and the thrombin-anti-thrombin complex (TAT). Surgery significantly (P<0.05) increased pro-thrombin time (PT), activated partial thromboplastin time, fibrinogen, D-dimers, TAT, F1+2 and FVIII up to 6 months. Conclusion: These data highlight the linked pro-coagulant and immunoinflammatory pathways in the multimodal management of oesophageal cancer, and suggest that the duration of current standard thromboprophylaxis regimens warrants further study. PMID:19953092

  15. Coagulation activation by MC28 fibrosarcoma cells facilitates lung tumor formation.

    PubMed

    Amirkhosravi, M; Francis, J L

    1995-01-01

    Tumor cells interact with the hemostatic system in various ways and may thus influence malignant growth and spread. MC28 fibrosarcoma cells possess a potent procoagulant activity (PCA) and form lung tumors following intravenous injection. The aim of this work was to study the relationship between PCA, intravascular coagulation and lung seeding in the MC28 model. MC28 cells were injected into control, warfarinized and heparinized hooded Lister rats. Coagulation changes were monitored by thromboelastography (TEG) and Sonoclot analysis (SA), lung fibrin formation by light and electron microscopy, tumor seeding by macroscopic counting and tumor cell and platelet deposition in the lungs by radiolabelling. PCA was measured by chromogenic assay. MC28 PCA was characterized as a tissue factor-factor VIIa complex that probably arose during cell culture or disaggregation of solid tumors. Injection of tumor cells caused marked coagulopathy and was rapidly (within 30 min) followed by fibrin deposition in the lungs and accumulation of radiolabelled platelets. Heparin and warfarin significantly reduced lung seeding (p < 0.001) and reduced retention of radiolabelled tumor cells in the pulmonary circulation (p < 0.01). Inhibition of cellular PCA by prior treatment with concanavalin A markedly reduced intravascular coagulation and lung seeding. We conclude that MC28 cells cause intravascular coagulation as a direct result of their procoagulant activity. The data suggest that tumor cells form complexes with platelets and fibrin which are retained in the lungs long enough for extravasation and seeding to occur.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Coagulation activation by MC28 fibrosarcoma cells facilitates lung tumor formation.

    PubMed

    Amirkhosravi, M; Francis, J L

    1995-01-01

    Tumor cells interact with the hemostatic system in various ways and may thus influence malignant growth and spread. MC28 fibrosarcoma cells possess a potent procoagulant activity (PCA) and form lung tumors following intravenous injection. The aim of this work was to study the relationship between PCA, intravascular coagulation and lung seeding in the MC28 model. MC28 cells were injected into control, warfarinized and heparinized hooded Lister rats. Coagulation changes were monitored by thromboelastography (TEG) and Sonoclot analysis (SA), lung fibrin formation by light and electron microscopy, tumor seeding by macroscopic counting and tumor cell and platelet deposition in the lungs by radiolabelling. PCA was measured by chromogenic assay. MC28 PCA was characterized as a tissue factor-factor VIIa complex that probably arose during cell culture or disaggregation of solid tumors. Injection of tumor cells caused marked coagulopathy and was rapidly (within 30 min) followed by fibrin deposition in the lungs and accumulation of radiolabelled platelets. Heparin and warfarin significantly reduced lung seeding (p < 0.001) and reduced retention of radiolabelled tumor cells in the pulmonary circulation (p < 0.01). Inhibition of cellular PCA by prior treatment with concanavalin A markedly reduced intravascular coagulation and lung seeding. We conclude that MC28 cells cause intravascular coagulation as a direct result of their procoagulant activity. The data suggest that tumor cells form complexes with platelets and fibrin which are retained in the lungs long enough for extravasation and seeding to occur.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7740497

  17. Absence of in vitro Procoagulant Activity in Immunoglobulin Preparations due to Activated Coagulation Factors

    PubMed Central

    Oviedo, Adriana E.; Bernardi, María E.; Guglielmone, Hugo A.; Vitali, María S.

    2015-01-01

    Summary Background Immunoglobulin (IG) products, including intravenous (IVIG) or subcutaneous (SCIG) immunoglobulins are considered safe and effective for medical therapy; however, a sudden and unexpected increase in thromboembolic events (TE) after administration of certain batches of IVIG products has been attributed to the presence of activated coagulation factors, mainly factor XIa. Our aims were to examine the presence of enduring procoagulant activity during the manufacturing process of IGs, with special focus on monitoring factor XIa, and to evaluate the presence of in vitro procoagulant activity attributed to coagulation factors in different lots of IVIG and SCIG. Methods Samples of different steps of IG purification, 19 lots of IVIG and 9 of SCIG were analyzed and compared with 1 commercial preparation of IVIG and 2 of SCIG, respectively. Factors II, VII, IX, XI and XIa and non-activated partial thromboplastin time (NAPTT) were assayed. Results The levels of factors II, VII, IX, X and XI were non-quantifiable once fraction II had been re-dissolved and in all analyzed lots of IVIG and SCIG. The level of factor XIa at that point was under the detection limits of the assay, and NAPTT yielded values greater than the control during the purification process. In SCIG, we detected higher concentrations of factor XIa in the commercial products, which reached values up to 5 times higher than the average amounts found in the 9 batches produced by UNC-Hemoderivados. Factor XIa in commercial IVIG reached levels slightly higher than those of the 19 batches produced by UNC-Hemoderivados. Conclusion IVIG and SCIG manufactured by UNC-Hemoderivados showed a lack of thrombogenic potential, as demonstrated not only by the laboratory data obtained in this study but also by the absence of any reports of TE registered by the post marketing pharmacovigilance department. PMID:26733772

  18. Plasmin and coagulant activities in a minicurd model system: Study of technological parameters.

    PubMed

    Vélez, M A; Perotti, M C; Candioti, M C; Bergamini, C V; Hynes, E R

    2016-09-01

    The effect of scalding temperature of the curd, the inclusion of a washing step, and the pH at whey drainage on plasmin and coagulant activities were assessed in a minicurd model of young hard cooked cheese. The variables were tested as follows: draining pH was assayed at 3 levels (4.6, 5.6, and 6.4), curd scalding temperature was tested at 50 and 56°C, and washing of the curd was examined at 2 levels (no washing step, and the replacement of the whey by water). Increase in pH at whey drainage and washing of the curd had a positive effect on plasmin activity, which was also evidenced by compatible changes in soluble peptide profiles. No effect of increased cooking temperature was found on plasmin activity. Plasminogen activation was not verified in any treatment. As for coagulant, lower pH values at whey drainage and a decrease in curd cooking temperature increased its activity; washing of the curd showed no influence on coagulant residual activity. These results were consistent with proteolysis described by peptide profiles, electrophoresis, and soluble nitrogen fractions.

  19. Plasmin and coagulant activities in a minicurd model system: Study of technological parameters.

    PubMed

    Vélez, M A; Perotti, M C; Candioti, M C; Bergamini, C V; Hynes, E R

    2016-09-01

    The effect of scalding temperature of the curd, the inclusion of a washing step, and the pH at whey drainage on plasmin and coagulant activities were assessed in a minicurd model of young hard cooked cheese. The variables were tested as follows: draining pH was assayed at 3 levels (4.6, 5.6, and 6.4), curd scalding temperature was tested at 50 and 56°C, and washing of the curd was examined at 2 levels (no washing step, and the replacement of the whey by water). Increase in pH at whey drainage and washing of the curd had a positive effect on plasmin activity, which was also evidenced by compatible changes in soluble peptide profiles. No effect of increased cooking temperature was found on plasmin activity. Plasminogen activation was not verified in any treatment. As for coagulant, lower pH values at whey drainage and a decrease in curd cooking temperature increased its activity; washing of the curd showed no influence on coagulant residual activity. These results were consistent with proteolysis described by peptide profiles, electrophoresis, and soluble nitrogen fractions. PMID:27423946

  20. Network-Based Biomarkers for Cold Coagulation Blood Stasis Syndrome and the Therapeutic Effects of Shaofu Zhuyu Decoction in Rats

    PubMed Central

    Su, Shulan; Duan, Jinao; Cui, Wenxia; Shang, Erxing; Liu, Pei; Bai, Gang; Guo, Sheng; Qian, Dawei; Tang, Yuping

    2013-01-01

    In this study, the reverse docking methodology was applied to predict the action targets and pathways of Shaofu Zhuyu decoction (SFZYD) bioactive ingredients. Furthermore, Traditional Chinese Medicine (TCM) cold coagulation blood stasis (CCBS) syndrome was induced in female Sprague-Dawley rats with an ice-water bath and epinephrine, and SFZYD was used to treat CCBS syndrome. A metabolomic approach was used to evaluate changes in the metabolic profiles and to analyze the pharmacological mechanism of SFZYD actions. Twenty-three potential protein targets and 15 pathways were discovered, respectively; among these, pathways are associated with inflammation and immunological stress, hormone metabolism, coagulation function, and glycometabolism. There were also changes in the levels of endogenous metabolites of LysoPCs and glucuronides. Twenty endogenous metabolites were identified. Furthermore, the relative quantities of 6 endogenous metabolites in the plasma and 5 in the urine were significantly affected by SFZYD (P < 0.05). The pharmacological mechanism of SFZYD was partially associated with glycerophospholipid metabolism and pentose and glucuronate interconversions. In conclusion, our findings demonstrated that TCM CCBS pattern induced by ice water and epinephrine was complex and related to multiple metabolic pathways. SFZYD did regulate the TCM CCBS by multitargets, and biomarkers and SFZYD should be used for the clinical treatment of CCBS syndrome. PMID:24288569

  1. Minimum wound size for clotting: flowing blood coagulates on a single collagen fiber presenting tissue factor and von Willebrand factor.

    PubMed

    Zhu, Shu; Tomaiuolo, Maurizio; Diamond, Scott L

    2016-08-01

    It is unknown if a lower size limit exists for human blood coagulation under flow over physiological vessel wall triggers as small as a single collagen fiber. Prior determinations of the smallest sized surface stimuli necessary for clotting of human blood, defined as the patch size threshold, have not deployed whole blood, hemodynamic flow, and platelet adhesive stimuli. For whole blood perfused in microfluidic devices, we report that steady venous flow (wall shear rate, 100 s(-1)) was sufficient to drive platelet deposition on 20 micron long zones of collagen fibers or on a single fiber. With tissue factor (TF)-coated collagen, flowing blood generated robust platelet deposits, platelet-localized thrombin, and fibrin on a single collagen fiber, thus demonstrating the absence of a physiological patch size threshold under venous flow. In contrast, at arterial wall shear rate (1000 s(-1)) with TF present, essentially no platelet or fibrin deposition occurred on 20 micron collagen zones or on a single collagen fiber, demonstrating a patch threshold, which was overcome by pre-coating the collagen with von Willebrand factor (vWF). For venous flows, human blood can clot on one of the smallest biological units of a single collagen fiber presenting TF. For arterial flows, vWF together with TF allows human blood to generate thrombin and fibrin on a patch stimulus as limited as a single collagen fiber. vWF-dependent platelet adhesion represents a particle-based sensing mechanism of micron-scale stimuli that then allows amplification of the molecular components of TF-driven thrombin and fibrin production under arterial flow. PMID:27339024

  2. Minimum wound size for clotting: flowing blood coagulates on a single collagen fiber presenting tissue factor and von Willebrand factor.

    PubMed

    Zhu, Shu; Tomaiuolo, Maurizio; Diamond, Scott L

    2016-08-01

    It is unknown if a lower size limit exists for human blood coagulation under flow over physiological vessel wall triggers as small as a single collagen fiber. Prior determinations of the smallest sized surface stimuli necessary for clotting of human blood, defined as the patch size threshold, have not deployed whole blood, hemodynamic flow, and platelet adhesive stimuli. For whole blood perfused in microfluidic devices, we report that steady venous flow (wall shear rate, 100 s(-1)) was sufficient to drive platelet deposition on 20 micron long zones of collagen fibers or on a single fiber. With tissue factor (TF)-coated collagen, flowing blood generated robust platelet deposits, platelet-localized thrombin, and fibrin on a single collagen fiber, thus demonstrating the absence of a physiological patch size threshold under venous flow. In contrast, at arterial wall shear rate (1000 s(-1)) with TF present, essentially no platelet or fibrin deposition occurred on 20 micron collagen zones or on a single collagen fiber, demonstrating a patch threshold, which was overcome by pre-coating the collagen with von Willebrand factor (vWF). For venous flows, human blood can clot on one of the smallest biological units of a single collagen fiber presenting TF. For arterial flows, vWF together with TF allows human blood to generate thrombin and fibrin on a patch stimulus as limited as a single collagen fiber. vWF-dependent platelet adhesion represents a particle-based sensing mechanism of micron-scale stimuli that then allows amplification of the molecular components of TF-driven thrombin and fibrin production under arterial flow.

  3. Prophylactic use of tranexamic acid combined with thrombelastogram guided coagulation management may reduce blood loss and allogeneic transfusion in pediatric hemispherectomy: case series.

    PubMed

    Xiao, Wei; Fu, Wenya; Wang, Tianlong; Zhao, Lei

    2016-09-01

    Hemispherectomy is an established surgical procedure to treat medically refractory epilepsy caused by diffuse hemispheric diseases. The most common complication of hemispherectomy is intraoperative bleeding. Perioperative allogeneic blood transfusion increases mortality and morbidity in pediatric patients. Etiologies of massive blood loss during hemispherectomy include intraoperative diffuse vascular damage, antileptic drugs induced coagulation dysfunction, hyperfibrinolysis and dilutional coagulopathy. Great efforts should be made to minimize the need of blood transfusion. We present a series of three cases undergoing pediatric hemispherectomy, where a new algorithm was employed to manage coagulation. This new algorithm was mainly based on timely thrombelastogram analyses guided clotting factors supplement and continuous administration of tranexamic acid. In our cases, the amount of blood loss and subsequent allogeneic blood transfusion seemed to be less than literature reported. PMID:27555151

  4. Physiological levels of blood coagulation factors IX and X control coagulation kinetics in an in vitro model of circulating tissue factor

    NASA Astrophysics Data System (ADS)

    Tormoen, Garth W.; Khader, Ayesha; Gruber, András; McCarty, Owen J. T.

    2013-06-01

    Thrombosis significantly contributes to cancer morbidity and mortality. The mechanism behind thrombosis in cancer may be circulating tissue factor (TF), as levels of circulating TF are associated with thrombosis. However, circulating TF antigen level alone has failed to predict thrombosis in patients with cancer. We hypothesize that coagulation factor levels regulate the kinetics of circulating TF-induced thrombosis. Coagulation kinetics were measured as a function of individual coagulation factor levels and TF particle concentration. Clotting times increased when pooled plasma was mixed at or above a ratio of 4:6 with PBS. Clotting times increased when pooled plasma was mixed at or above a ratio of 8:2 with factor VII-depleted plasma, 7:3 with factor IX- or factor X-depleted plasmas, or 2:8 with factor II-, V- or VIII-depleted plasmas. Addition of coagulation factors VII, X, IX, V and II to depleted plasmas shortened clotting and enzyme initiation times, and increased enzyme generation rates in a concentration-dependent manner. Only additions of factors IX and X from low-normal to high-normal levels shortened clotting times and increased enzyme generation rates. Our results demonstrate that coagulation kinetics for TF particles are controlled by factor IX and X levels within the normal physiological range. We hypothesize that individual patient factor IX and X levels may be prognostic for susceptibility to circulating TF-induced thrombosis.

  5. Physiological levels of blood coagulation factors IX and X control coagulation kinetics in an in vitro model of circulating tissue factor

    PubMed Central

    Tormoen, Garth W.; Khader, Ayesha; Gruber, András; McCarty, Owen J.T.

    2013-01-01

    Thrombosis significantly contributes to cancer morbidity and mortality. The mechanism behind thrombosis in cancer may be circulating tissue factor (TF), as levels of circulating TF are associated with thrombosis. However, circulating TF antigen level alone has failed to predict thrombosis in patients with cancer. We hypothesize that coagulation factor levels regulate the kinetics of circulating TF-induced thrombosis. Coagulation kinetics were measured as a function of individual coagulation factor levels and TF particle concentration. Clotting times increased when pooled plasma was mixed at or above a ratio of 4:6 with PBS. Clotting times increased when pooled plasma was mixed at or above a ratio of 8:2 with factor VII-depleted plasma, 7:3 with factor IX- or factor X-depleted plasmas, or 2:8 with factor II-, V- or VIII-depleted plasmas. Addition of coagulation factors VII, X, IX, V and II to depleted plasmas shortened clotting and enzyme initiation times, and increased enzyme generation rates in a concentration-dependent manner. Only additions of factors IX and X from low-normal to high-normal levels shortened clotting times and increased enzyme generation rates. Our results demonstrate that coagulation kinetics for TF particles are controlled by factor IX and X levels within the normal physiological range. We hypothesize that individual patient factor IX and X levels may be prognostic for susceptibility to circulating TF-induced thrombosis. PMID:23585459

  6. Agent based modeling of blood coagulation system: implementation using a GPU based high speed framework.

    PubMed

    Chen, Wenan; Ward, Kevin; Li, Qi; Kecman, Vojislav; Najarian, Kayvan; Menke, Nathan

    2011-01-01

    The coagulation and fibrinolytic systems are complex, inter-connected biological systems with major physiological roles. The complex, nonlinear multi-point relationships between the molecular and cellular constituents of two systems render a comprehensive and simultaneous study of the system at the microscopic and macroscopic level a significant challenge. We have created an Agent Based Modeling and Simulation (ABMS) approach for simulating these complex interactions. As the scale of agents increase, the time complexity and cost of the resulting simulations presents a significant challenge. As such, in this paper, we also present a high-speed framework for the coagulation simulation utilizing the computing power of graphics processing units (GPU). For comparison, we also implemented the simulations in NetLogo, Repast, and a direct C version. As our experiments demonstrate, the computational speed of the GPU implementation of the million-level scale of agents is over 10 times faster versus the C version, over 100 times faster versus the Repast version and over 300 times faster versus the NetLogo simulation. PMID:22254271

  7. The effect of surface contact activation and temperature on plasma coagulation with an RNA aptamer directed against factor IXa.

    PubMed

    Krishnan, Anandi; Vogler, Erwin A; Sullenger, Bruce A; Becker, Richard C

    2013-01-01

    The anticoagulant properties of a novel RNA aptamer that binds FIXa depend collectively on the intensity of surface contact activation of human blood plasma, aptamer concentration, and its binding affinity for FIXa. Accordingly, anticoagulation efficiency of plasma containing any particular aptamer concentration is low when coagulation is strongly activated by hydrophilic surfaces compared to the anticoagulation efficiency in plasma that is weakly activated by hydrophobic surfaces. Anticoagulation efficiency is lower at hypothermic temperatures possibly because aptamer-FIXa binding decreases with decreasing temperatures. Experimental results demonstrating these trends are qualitatively interpreted in the context of a previously established model of anticoagulation efficiency of thrombin-binding DNA aptamers that exhibit anticoagulation properties similar to the FIXa aptamer. In principle, FIXa aptamer anticoagulants should be more efficient and therefore more clinically useful than thrombin-binding aptamers because aptamer binding to FIXa competes only with FX that is at much lower blood concentration than fibrinogen (FI) that competes with thrombin-binding aptamers. Our findings may have translatable relevance in the application of aptamer anticoagulants for clinical conditions in which blood is in direct contact with non-biological surfaces such as those encountered in cardiopulmonary bypass circuits. PMID:23054460

  8. The role of cytokines in activation of coagulation and fibrinolysis in dengue shock syndrome.

    PubMed

    Suharti, Catharina; van Gorp, Eric C M; Setiati, Tatty E; Dolmans, Wil M V; Djokomoeljanto, Robert J; Hack, C Erik; ten, Cate Hugo; van der Meer, Jos W M

    2002-01-01

    In a prospective clinical study of 50 patients with Dengue Shock Syndrome (DSS), we investigated the association of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-1 receptor antagonist (IL-1Ra), and IL-6 with activation markers of coagulation (F1+2 and TATc) and fibrinolysis (t-PA, PAPc, and D-dimer). We found that TNF-alpha, IL-1beta and Il-1Ra, but not IL-6, concentrations were elevated in the circulation during the early stage of infection and at discharge from hospital. TNF-alpha was significantly associated with D-dimer, an activation marker of fibrinolysis (p < 0.003), but not with activation markers of coagulation. IL-1beta was significantly associated with t-PA (p < 0.03). IL-1Ra was significantly associated with F1+2, TATc (p < 0.04 and p < 0.02, respectively), whereas IL-6 was significantly associated with both, activation markers of coagulation (F1+2; p < 0.03) and fibrinolysis (PAPc; p = 0.002). Our data are in line with studies in bacterial sepsis. In severe dengue virus infection the same cytokines are involved in the onset and regulation of hemostasis.

  9. Activation of the intrinsic pathway of coagulation in children with meningococcal septic shock.

    PubMed

    Wuillemin, W A; Fijnvandraat, K; Derkx, B H; Peters, M; Vreede, W; ten Cate, H; Hack, C E

    1995-12-01

    Meningococcal septic shock (MSS) is complicated by activation of coagulation, fibrinolytic, and complement systems. We studied the contact system of the intrinsic pathway of coagulation in thirteen children with MSS. Activation was assessed upon admittance to the intensive care unit and 48 h thereafter, based on the measurement of factor XII- (FXII), prekallikrein- and factor XI (FXI) antigen levels, as well as on the detection of FXIa-FXIa inhibitor, FXIIa-C1-inhibitor, and kallikrein-C1-inhibitor complexes, respectively. Levels of FXII, prekallikrein and FXI were reduced to about 50% in all patients on admission, and were significantly higher 48 h later. FXIIa-C1-inhibitor complexes were elevated in 7 patients, and kallikrein-C1-inhibitor complexes in 2 patients. FXIa-alpha 1-antitrypsin complexes were elevated in all patients, FXIa-C1-inhibitor complexes in nine, and FXIa-antithrombin III complexes in one patient. We conclude that patients with MSS have activation of the contact system, which may contribute to activation of coagulation, and thus to morbidity and mortality.

  10. Rat prostate tumors express cancer procoagulant, an activator of coagulation factor X.

    PubMed

    Kamocka, Malgorzata; Pollard, Morris; Suckow, Mark; Mielicki, Wojciech P; Rosen, Elliot D

    2008-06-01

    Two common procoagulant activities associated with tumors are tissue factor and cancer procoagulant (CP), an activator of coagulation factor X. We have identified a convenient source of CP in transplanted Lobund-Wistar rat PA3 prostate tumors. CP activity was purified from 5 independent transplanted prostate tumors by column chromatography. The protein activated factor X in the absence of TF and factor VII. An antihuman CP antibody recognized rat CP in an ELISA and inactivated CP activity in a chromogenic assay. Lobund-Wistar prostate tumors may provide a convenient animal model useful in determining the role of CP in cancer development.

  11. Combining bioinformatics, chemoinformatics and experimental approaches to design chemical probes: Applications in the field of blood coagulation.

    PubMed

    Villoutreix, B O

    2016-07-01

    Bioinformatics and chemoinformatics approaches contribute to the discovery of novel targets, chemical probes, hits, leads and medicinal drugs. A vast repertoire of computational methods has indeed been reported over the years and in this review, I will briefly introduce some concepts and approaches, namely the analysis of potential therapeutic target binding pockets, the preparation of compound collections and virtual screening. An example of application is provided for two proteins acting in the blood coagulation system. Overall, in silico methods have been shown to improve R and D productivity in both, academic settings and in the private sector, if they are integrated in a rational manner with experimental approaches. However, integration of tools and pluridisciplinarity are seldom achieved. Efforts should be done in this direction as pluridisciplinarity and a true acknowledgment of all the contributing actors along the value chain could enhance innovation and reduce skyrocketing costs. PMID:27133312

  12. Impacts of coagulation on the adsorption of organic micropollutants onto powdered activated carbon in treated domestic wastewater.

    PubMed

    Altmann, Johannes; Zietzschmann, Frederik; Geiling, Eva-Linde; Ruhl, Aki Sebastian; Sperlich, Alexander; Jekel, Martin

    2015-04-01

    The application of powdered activated carbon (PAC) as an advanced wastewater treatment step for the removal of organic micropollutants (OMP) necessitates complete separation of the PAC particles, e.g. by coagulation. In this study, potential positive or negative indirect or direct effects of coagulation on the adsorption of OMPs onto PAC in treated wastewater were investigated. Although the concentration of dissolved organic matter (DOM) was significantly reduced by coagulation, the selective removal of mainly larger DOM components such as biopolymers and humic substances did not improve subsequent OMP adsorption onto PAC, demonstrating that coagulation has minor effects on DOM constituents that are relevant for direct competition or pore blocking. The combination of coagulation and adsorption yielded the sum of the individual removals, as adsorption predominantly affected smaller compounds. While the formation of flocs led to visible incorporation of PAC particles, no significant mass transfer limitations impeded the OMP adsorption. As a result, the dosing sequence of coagulant and PAC is not critical for efficient adsorption of OMPs onto PAC. The relationships between adsorptive OMP removal and corresponding reduction of UV absorption at 254 nm (UVA254) as a promising surrogate correlation for the real-time monitoring and PAC adjustment were affected by coagulation, leading to individual correlations depending on the water composition. Correcting for UVA254 reduction by coagulation produces adsorptive UVA254 removal, which correlates highly with OMP removal for different WWTP effluents and varying coagulant doses and can be applied in combined adsorption/coagulation processes to predict OMP removal and control PAC dosing.

  13. Impacts of coagulation on the adsorption of organic micropollutants onto powdered activated carbon in treated domestic wastewater.

    PubMed

    Altmann, Johannes; Zietzschmann, Frederik; Geiling, Eva-Linde; Ruhl, Aki Sebastian; Sperlich, Alexander; Jekel, Martin

    2015-04-01

    The application of powdered activated carbon (PAC) as an advanced wastewater treatment step for the removal of organic micropollutants (OMP) necessitates complete separation of the PAC particles, e.g. by coagulation. In this study, potential positive or negative indirect or direct effects of coagulation on the adsorption of OMPs onto PAC in treated wastewater were investigated. Although the concentration of dissolved organic matter (DOM) was significantly reduced by coagulation, the selective removal of mainly larger DOM components such as biopolymers and humic substances did not improve subsequent OMP adsorption onto PAC, demonstrating that coagulation has minor effects on DOM constituents that are relevant for direct competition or pore blocking. The combination of coagulation and adsorption yielded the sum of the individual removals, as adsorption predominantly affected smaller compounds. While the formation of flocs led to visible incorporation of PAC particles, no significant mass transfer limitations impeded the OMP adsorption. As a result, the dosing sequence of coagulant and PAC is not critical for efficient adsorption of OMPs onto PAC. The relationships between adsorptive OMP removal and corresponding reduction of UV absorption at 254 nm (UVA254) as a promising surrogate correlation for the real-time monitoring and PAC adjustment were affected by coagulation, leading to individual correlations depending on the water composition. Correcting for UVA254 reduction by coagulation produces adsorptive UVA254 removal, which correlates highly with OMP removal for different WWTP effluents and varying coagulant doses and can be applied in combined adsorption/coagulation processes to predict OMP removal and control PAC dosing. PMID:25582393

  14. Blood Pressure. Learning Activity Package.

    ERIC Educational Resources Information Center

    Hime, Kirsten

    This learning activity package on blood pressure is one of a series of 12 titles developed for use in health occupations education programs. Materials in the package include objectives, list of materials needed, a list of definitions, information sheets, reviews (self evaluations) of portions of the content, and answers to reviews. These topics…

  15. Repeated action of a constant magnetic field on the blood coagulation system in artificially produced anemia

    NASA Technical Reports Server (NTRS)

    Zabrodina, L. V.

    1974-01-01

    Changes are discussed in the coagulatory system of the blood in rabbits under the influence of a constant magnetic field of an intensity of 2500 oersteds against the background of artificially induced anemia. Reversibility of the changes produced and the presence of the adaptational effect are noted. Taking all this into consideration, the changes involving the coagulatory system of the blood which arise under the influence of a constant magnetic field may be considered to have a nerve-reflex nature.

  16. The effect of covalently bonded conjugated linoleic acid on the reduction of oxidative stress and blood coagulation for polysulfone hemodialyzer membrane.

    PubMed

    Kung, Fu-Chen; Yang, Ming-Chine

    2006-05-30

    Conjugated linoleic acid (CLA) was covalently bonded to a layer of poly(acrylic acid) (PAA) grafted onto the surface of polysulfone (PSF) membranes. The effect of CLA-bonding on oxidative stress and blood coagulation was then evaluated. The surface was characterized with contact angle measurement and FTIR spectroscopy. Blood coagulation, platelet aggregation, and oxidative stress were evaluated using human blood. The complete blood count (CBC) and coagulation time (CT) were evaluated in vitro for hemocompatibility. The production of reactive oxygen species (ROS) was measured by the chemiluminescence (CL) method to evaluate the oxidative stress. The results showed that the CLA-bonding PSF membrane exhibited more stable CBC values, longer CT, and less adsorption of plasma proteins than the unmodified PSF membrane. In addition, the CL counts of hydrogen peroxide and superoxide values for CLA-bonding PSF membrane were more stable than for unmodified PSF membrane. These results demonstrate that CLA-bonding can improve the blood compatibility of PSF membrane. The CLA-bonding PSF membrane could offer protection for patients against oxidative stress and could also reduce the dosage of anticoagulant required during hemodialysis.

  17. Effects of Rivaroxaban on Platelet Activation and Platelet–Coagulation Pathway Interaction

    PubMed Central

    Heitmeier, Stefan; Laux, Volker

    2015-01-01

    Introduction: Activation of coagulation and platelets is closely linked, and arterial thrombosis involves coagulation activation as well as platelet activation and aggregation. In these studies, we investigated the possible synergistic effects of rivaroxaban in combination with antiplatelet agents on thrombin generation and platelet aggregation in vitro and on arterial thrombosis and hemostasis in rat models. Materials and Methods: Thrombin generation was measured by the Calibrated Automated Thrombogram method (0.5 pmol/L tissue factor) using human platelet-rich plasma (PRP) spiked with rivaroxaban (15, 30, or 60 ng/mL), ticagrelor (1.0 µg/mL), and acetylsalicylic acid (ASA; 100 µg/mL). Tissue factor-induced platelet aggregation was measured in PRP spiked with rivaroxaban (15 or 30 ng/mL), ticagrelor (1 or 3 µg/mL), or a combination of these. An arteriovenous (AV) shunt model in rats was used to determine the effects of rivaroxaban (0.01, 0.03, or 0.1 mg/kg), clopidogrel (1 mg/kg), ASA (3 mg/kg), and combinations on arterial thrombosis. Results: Rivaroxaban inhibited thrombin generation in a concentration-dependent manner and the effect was enhanced with ticagrelor and ticagrelor plus ASA. Rivaroxaban and ticagrelor also concentration-dependently inhibited tissue factor-induced platelet aggregation, and their combination increased the inhibition synergistically. In the AV shunt model, rivaroxaban dose-dependently reduced thrombus formation. Combining subefficacious or weakly efficacious doses of rivaroxaban with ASA or ASA plus clopidogrel increased the antithrombotic effect. Conclusion: These data indicate that the combination of rivaroxaban with single or dual antiplatelet agents works synergistically to reduce platelet activation, which may in turn lead to the delayed/reduced formation of coagulation complexes and vice versa, thereby enhancing antithrombotic potency. PMID:25848131

  18. The first report on coagulation and phospholipase A2 activities of Persian Gulf lionfish, Pterois russelli, an Iranian venomous fish.

    PubMed

    Memar, Bahareh; Jamili, Shahla; Shahbazzadeh, Delavar; Bagheri, Kamran Pooshang

    2016-04-01

    Pterois russelli is a venomous fish belonging to scorpionidae family. Regarding to high significance value for tracing potential therapeutic molecules and special agents from venomous marine creatures, the present study was aimed to characterization of the Persian Gulf lionfish venom. Proteolytic, phospholipase, hemolytic, coagulation, edematogenic and dermonecrotic activities were determined for extracted venom. The LD50 of P. russelli venom was determined by intravenous injection in white Balb/c mice. Phospholipase A2 activity was recorded at 20 μg of total venom. Coagulation activity on human plasma was shown by Prothrombin Time (PT) and activated Partial Thromboplastin Time (APTT) assays and coagulation visualized after 7 and 14 s respectively for 60 μg of crude venom. LD50 was calculated as 10.5 mg/kg. SDS-PAGE revealed the presence of major and minor protein bands between 6 and 205 kDa. Different amounts of crude venom ranged from 1.87 to 30 μg showed proteolytic activity on casein. The highest edematic activity was detected at 20 μg. Our findings showed that the edematic activity was dose dependent and persisted for 48 h after injection. The crude venom did not induce dermonecrotic activity on rabbit skin and showed no hemolytic activity on human, mouse and rabbit erythrocytes. This is the first report for phospholipase A2 and coagulation activity in venomous fish and venomous marine animals respectively. Proteolytic activity of P. russelli venom is in accordance with the other genara of scorpionidae family. According to venom activity on intrinsic and extrinsic coagulation pathways, lionfish venom would be contained an interesting pharmaceutical agent. This study is pending to further characterization of phospholipase A2, coagulation, and protease activities and also in vivo activity on animal model of surface and internal bleeding.

  19. Coagulation factor V mediates inhibition of tissue factor signaling by activated protein C in mice.

    PubMed

    Liang, Hai Po H; Kerschen, Edward J; Basu, Sreemanti; Hernandez, Irene; Zogg, Mark; Jia, Shuang; Hessner, Martin J; Toso, Raffaella; Rezaie, Alireza R; Fernández, José A; Camire, Rodney M; Ruf, Wolfram; Griffin, John H; Weiler, Hartmut

    2015-11-19

    The key effector molecule of the natural protein C pathway, activated protein C (aPC), exerts pleiotropic effects on coagulation, fibrinolysis, and inflammation. Coagulation-independent cell signaling by aPC appears to be the predominant mechanism underlying its highly reproducible therapeutic efficacy in most animal models of injury and infection. In this study, using a mouse model of Staphylococcus aureus sepsis, we demonstrate marked disease stage-specific effects of the anticoagulant and cell signaling functions of aPC. aPC resistance of factor (f)V due to the R506Q Leiden mutation protected against detrimental anticoagulant effects of aPC therapy but also abrogated the anti-inflammatory and mortality-reducing effects of the signaling-selective 5A-aPC variant that has minimal anticoagulant function. We found that procofactor V (cleaved by aPC at R506) and protein S were necessary cofactors for the aPC-mediated inhibition of inflammatory tissue-factor signaling. The anti-inflammatory cofactor function of fV involved the same structural features that govern its cofactor function for the anticoagulant effects of aPC, yet its anti-inflammatory activities did not involve proteolysis of activated coagulation factors Va and VIIIa. These findings reveal a novel biological function and mechanism of the protein C pathway in which protein S and the aPC-cleaved form of fV are cofactors for anti-inflammatory cell signaling by aPC in the context of endotoxemia and infection.

  20. Coagulation-driven platelet activation reduces cholestatic liver injury and fibrosis in mice

    PubMed Central

    Joshi, N.; Kopec, A. K.; O’Brien, K. M.; Towery, K. L.; Cline-Fedewa, H.; Williams, K.J.; Copple, B. L.; Flick, M. J.; Luyendyk, J. P.

    2014-01-01

    Summary Background The coagulation cascade has been shown to participate in chronic liver injury and fibrosis, but the contribution of various thrombin targets, such as protease activated receptors (PARs) and fibrin(ogen), has not been fully described. Emerging evidence suggests that in some experimental settings of chronic liver injury, platelets can promote liver repair and inhibit liver fibrosis. However, the precise mechanisms linking coagulation and platelet function to hepatic tissue changes following injury remain poorly defined. Objectives To determine the role of PAR-4, a key thrombin receptor on mouse platelets, and fibrin(ogen) engagement of the platelet αIIbβ3 integrin in a model of cholestatic liver injury and fibrosis. Methods Biliary and hepatic injury was characterized following 4 week administration of the bile duct toxicant α-naphthylisothiocyanate (ANIT) (0.025%) in PAR-4-deficient mice (PAR-4−/− mice), mice expressing a mutant form of fibrin(ogen) incapable of binding integrin αIIbβ3 (FibγΔ5), and wild-type mice. Results Elevated plasma thrombin-antithrombin and serotonin levels, hepatic fibrin deposition and platelet accumulation in liver accompanied hepatocellular injury and fibrosis in ANIT-treated wild-type mice. PAR-4 deficiency reduced plasma serotonin levels, increased serum bile acid concentration, and exacerbated ANIT-induced hepatocellular injury and peribiliary fibrosis. Compared to PAR-4-deficient mice, ANIT-treated FibγΔ5 mice displayed more widespread hepatocellular necrosis accompanied by marked inflammation, robust fibroblast activation and extensive liver fibrosis. Conclusions Collectively, the results indicate that PAR-4 and fibrin-αIIbβ3 integrin engagement, pathways coupling coagulation to platelet activation, each exert hepatoprotective effects during chronic cholestasis. PMID:25353084

  1. An investigation of the coagulant activity of the venom of the saw-scaled viper (Echis carinatus) from Saudi Arabia.

    PubMed

    Kamiguti, A S; Theakston, R D; Tomy, S C

    1988-10-01

    Unlike the venom of Echis carinatus from India, Pakistan, Nigeria, Kenya, Iran and Oman, Saudi Arabian E. carinatus venom is a poor activator of prothrombin. However, it possesses similar defibrinogenating activity to the other venoms. This is because the venom from Saudi Arabian snakes contains a calcium-dependent factor X activator. It is suggested that in future studies of the coagulant activity of venoms, the determination of plasma coagulant activity should be carried out in the presence of added calcium ions. This applies particularly to those venoms which do not act on plasma or fibrinogen, but which do cause in vivo defibrinogenation. PMID:3257079

  2. Coagulation Changes during Presyncope and Recovery

    PubMed Central

    Cvirn, Gerhard; Schlagenhauf, Axel; Leschnik, Bettina; Koestenberger, Martin; Roessler, Andreas; Jantscher, Andreas; Vrecko, Karoline; Juergens, Guenther; Hinghofer-Szalkay, Helmut; Goswami, Nandu

    2012-01-01

    Orthostatic stress activates the coagulation system. The extent of coagulation activation with full orthostatic load leading to presyncope is unknown. We examined in 7 healthy males whether presyncope, using a combination of head up tilt (HUT) and lower body negative pressure (LBNP), leads to coagulation changes as well as in the return to baseline during recovery. Coagulation responses (whole blood thrombelastometry, whole blood platelet aggregation, endogenous thrombin potential, markers of endothelial activation and thrombin generation), blood cell counts and plasma mass density (for volume changes) were measured before, during, and 20 min after the orthostatic stress. Maximum orthostatic load led to a 25% plasma volume loss. Blood cell counts, prothrombin levels, thrombin peak, endogenous thrombin potential, and tissue factor pathway inhibitor levels increased during the protocol, commensurable with hemoconcentration. The markers of endothelial activation (tissue factor, tissue plasminogen activator), and thrombin generation (F1+2, prothrombin fragments 1 and 2, and TAT, thrombin-antithrombin complex) increased to an extent far beyond the hemoconcentration effect. During recovery, the markers of endothelial activation returned to initial supine values, but F1+2 and TAT remained elevated, suggestive of increased coagulability. Our findings of increased coagulability at 20 min of recovery from presyncope may have greater clinical significance than short-term procoagulant changes observed during standing. While our experiments were conducted in healthy subjects, the observed hypercoagulability during graded orthostatic challenge, at presyncope and in recovery may be an important risk factor particularly for patients already at high risk for thromboembolic events (e.g. those with coronary heart disease, atherosclerosis or hypertensives). PMID:22876309

  3. Activation of the contact system of coagulation does not contribute to the hemostatic imbalance in hypertriglyceridemia.

    PubMed

    Minnema, M C; Wittekoek, M E; Schoonenboom, N; Kastelein, J J; Hack, C E; ten Cate, H

    1999-10-01

    In vitro, triglyceride-rich lipoproteins may act as a surface to initiate the contact system of coagulation. Therefore, we studied the activation of factor XII (FXII), prekallikrein, and FXI and the generation of thrombin in 52 hypertriglyceridemic patients before and after 12 weeks of triglyceride-lowering treatment with gemfibrozil or n-3 polyunsaturated fatty acids. Thrombin generation was assessed by measuring the levels of prothrombin fragment F1+2 and thrombin-antithrombin (TAT) complexes. Contact activation was assessed by measuring FXIIa, kallikrein, and FXIa in complex with their major inhibitor, C1 inhibitor, and FXIa was also determined as part of a complex with alpha(1)-antitrypsin. Triglyceride and cholesterol levels decreased equally in both treatment groups. In the gemfibrozil group, there was a significant decrease in F1+2, while TAT complexes did not change. FXIIa- and kallikrein-C1 inhibitor complexes were elevated in 13% and 9% of the patients before treatment, respectively, and no changes were observed on triglyceride-lowering therapy. Also, no significant changes in regard to FXIa-C1 inhibitor and FXIa-alpha(1)-antitrypsin complexes were seen. FXIa-alpha(1)-antitrypsin complexes were present in 70% of the patients before therapy and were positively correlated with the level of TAT complexes. In conclusion, we did not detect an effect on activation markers of the contact coagulation system in hypertriglyceridemic patients after triglyceride-lowering therapy. Therefore, contact activation is not likely to contribute to the hypercoagulability seen in these patients.

  4. Elimination of interleukin 6 attenuates coagulation activation in experimental endotoxemia in chimpanzees.

    PubMed

    van der Poll, T; Levi, M; Hack, C E; ten Cate, H; van Deventer, S J; Eerenberg, A J; de Groot, E R; Jansen, J; Gallati, H; Büller, H R

    1994-04-01

    The role of interleukin 6 (IL-6) in the toxic sequelae of sepsis is controversial. To assess the part of IL-6 in inflammatory responses to endotoxin, we investigated eight chimpanzees after either a bolus intravenous injection of Escherichia coli endotoxin (n = 4; 4 ng/kg) or after the same dose of endotoxin with a simultaneous bolus intravenous injection of an anti-IL-6 mAb (30 mg; n = 4). Anti-IL-6 did not affect the induction of the cytokine network (tumor necrosis factor [TNF], soluble TNF receptors types I and II, and IL-8) by endotoxin, nor did it influence the occurrence of a neutrophilic leukocytosis and neutrophil degranulation, as monitored by the measurement of elastase-alpha 1-antitrypsin complexes. In contrast, anti-IL-6 markedly attenuated endotoxin-induced activation of coagulation, monitored with the plasma levels of the prothrombin fragment F1+2 and thrombin-antithrombin III complexes, whereas activation of fibrinolysis, determined with the plasma concentrations of plasmin-alpha 2-antiplasmin complexes, remained unaltered. We conclude that IL-6 does not have a feedback effect on the release of other cytokines after injection of endotoxin, and that it is not involved in endotoxin-induced neutrophilia or neutrophil degranulation. IL-6 is, however, an important intermediate factor in activation of coagulation in low grade endotoxemia in chimpanzees.

  5. Surface-loop residue Lys316 in blood coagulation Factor IX is a major determinant for Factor X but not antithrombin recognition.

    PubMed

    Kolkman, J A; Mertens, K

    2000-09-15

    The active site of activated Factor IX (FIXa) and related blood-coagulation enzymes is surrounded by a number of highly variable surface loops, which contribute to the characteristic substrate specificity of each individual enzyme. FIX residue Lys(316) is located in one of these loops and mutation of this residue to Glu is associated with haemophilia B. In the present study we investigated the functional role of Lys(316) in human FIXa by analysing the purified and activated FIX mutants FIXa-K316E and FIXa-K316A. FIXa-K316E was indistinguishable from normal FIXa in binding the competitive active-site inhibitor p-aminobenzamidine. In addition, substitution of Glu for Lys(316) had no significant effect on the reactivity towards various synthetic tripeptide substrates. Inhibition by the macromolecular inhibitor antithrombin was only slightly reduced for both FIXa mutants (less than 2-fold). In contrast, proteolytic activity of FIXa-K316E towards the natural substrate Factor X (FX) was virtually lacking, while the Lys(316) to Ala mutation resulted in a more than 10-fold reduction in FX activation. Thus residue Lys(316) plays a key role in FIXa activity towards FX. The requirement for Lys at position 316 for FX activation was also evident in the presence of the cofactor activated Factor VIII, although to a lesser extent than in its absence. These data demonstrate that Lys(316) specifically determines the reactivity of FIXa towards its natural substrate FX, but not to synthetic peptide substrates or antithrombin. PMID:10970782

  6. Behavior of optical properties of coagulated blood sample at 633 nm wavelength

    NASA Astrophysics Data System (ADS)

    Morales Cruzado, Beatriz; Vázquez y Montiel, Sergio; Delgado Atencio, José Alberto

    2011-03-01

    Determination of tissue optical parameters is fundamental for application of light in either diagnostics or therapeutical procedures. However, in samples of biological tissue in vitro, the optical properties are modified by cellular death or cellular agglomeration that can not be avoided. This phenomena change the propagation of light within the biological sample. Optical properties of human blood tissue were investigated in vitro at 633 nm using an optical setup that includes a double integrating sphere system. We measure the diffuse transmittance and diffuse reflectance of the blood sample and compare these physical properties with those obtained by Monte Carlo Multi-Layered (MCML). The extraction of the optical parameters: absorption coefficient μa, scattering coefficient μs and anisotropic factor g from the measurements were carried out using a Genetic Algorithm, in which the search procedure is based in the evolution of a population due to selection of the best individual, evaluated by a function that compares the diffuse transmittance and diffuse reflectance of those individuals with the experimental ones. The algorithm converges rapidly to the best individual, extracting the optical parameters of the sample. We compare our results with those obtained by using other retrieve procedures. We found that the scattering coefficient and the anisotropic factor change dramatically due to the formation of clusters.

  7. In vitro/in vivo effect of Citrus limon (L. Burm. f.) juice on blood parameters, coagulation and anticoagulation factors in rabbits.

    PubMed

    Riaz, Azra; Khan, Rafeeq Alam; Mirza, Talat; Mustansir, Tazeen; Ahmed, Mansoor

    2014-07-01

    The genus Citrus of the family Rutaceae includes many species e.g. Citrus indica, Citrus aurantifolia and Citrus limon, among which Citrus limon L. Burm. f. has been reported to have highest antimicrobial activity. It is used as antidote against certain venom, due to its platelet inhibitory effect and also reported to have hypocholesterolemic effect. However its anticoagulant and thrombolytic effect were not been investigated, hence a prospective in-vitro/in-vivo study was designed to determine the effect of Citrus limon on blood parameters, coagulation and anticoagulation factors. In-vitro tests revealed highly significant increase in thrombin time and activated partial thromboplastin time by Citrus limon, whereas fibrinogen concentration was significantly reduced in comparison to control, however prothrombin time was not affected significantly. In-vivo testing of Citrus limon was done at three different doses i.e. 0.2ml/kg, 0.4ml/kg and 0.6ml/kg in healthy rabbits. Significant changes were observed in hematological parameters such as erythrocytes, hemoglobin and mean corpuscular hemoglobin concentration. Bleeding time and thrombin time was significantly prolonged and there was increase in protein C and thrombin antithrombin complex levels. These results may be due to inactivation of thrombin because it significantly decreases fibrinogen concentration and inhibit platelet aggregation. Citrus limon showed maximal anticoagulant effect at 0.4ml/kg, which suggest that Citrus limon possesses an anti-thrombin component and could prevent thrombosis playing a cardio protective role.

  8. Effects of three novel metalloproteinases from the venom of the West African saw-scaled viper, Echis ocellatus on blood coagulation and platelets.

    PubMed

    Howes, J-M; Kamiguti, A S; Theakston, R D G; Wilkinson, M C; Laing, G D

    2005-06-20

    Two metalloproteinases, a 24-kDa P-I EoVMP1 and a 56-kDa P-III EoVMP2, have recently been isolated from the venom of the West African saw-scaled viper Echis ocellatus. We now reveal a new 65-kDa haemorrhagic group P-III metalloproteinase which we have designated EoVMP3. The aim of this study was to determine whether these three snake venom metalloproteinases (SVMPs) affect platelets and blood coagulation. EoVMP1 had no effect on the aggregation of washed human platelets, whereas EoVMP2 inhibited collagen-induced platelet aggregation. In contrast, EoVMP3 did not inhibit the aggregation of platelets by collagen but instead activated platelets in the absence of any additional co-factors. All three SVMPs were capable of activating prothrombin to varying degrees and can therefore be described as procoagulants. EoVMP1, EoVMP2 and EoVMP3 share sequence identity with other members of the reprolysin family, but differ greatly in their effects on some of the components that control haemostasis. PMID:15863354

  9. Removal of humic and tannic acids by adsorption-coagulation combined systems with activated biochar.

    PubMed

    Jung, Chanil; Phal, Narong; Oh, Jeill; Chu, Kyoung Hoon; Jang, Min; Yoon, Yeomin

    2015-12-30

    Despite recent interest in transforming biomass into bio-oil and syngas, there is inadequate information on the compatibility of byproducts (e.g., biochar) with agriculture and water purification infrastructures. A pyrolysis at 300°C yields efficient production of biochar, and its physicochemical properties can be improved by chemical activation, resulting in a suitable adsorbent for the removal of natural organic matter (NOM), including hydrophobic and hydrophilic substances, such as humic acids (HA) and tannic acids (TA), respectively. In this study, the adsorption affinities of different HA and TA combinations in NOM solutions were evaluated, and higher adsorption affinity of TA onto activated biochar (AB) produced in the laboratory was observed due to its superior chemisorption tendencies and size-exclusion effects compared with that of HA, whereas hydrophobic interactions between adsorbent and adsorbate were deficient. Assessment of the AB role in an adsorption-coagulation hybrid system as nuclei for coagulation in the presence of aluminum sulfate (alum) showed a synergistic effect in a HA-dominated NOM solution. An AB-alum hybrid system with a high proportion of HA in the NOM solution may be applicable as an end-of-pipe solution.

  10. Low ADAMTS-13 activity during hemorrhagic events with disseminated intravascular coagulation.

    PubMed

    Chinen, Yoshiaki; Kuroda, Junya; Ohshiro, Muneo; Shimura, Yuji; Mizutani, Shinsuke; Nagoshi, Hisao; Sasaki, Nana; Nakayama, Ryuko; Kiyota, Miki; Yamamoto-Sugitani, Mio; Kobayashi, Tsutomu; Matsumoto, Yosuke; Horiike, Shigeo; Taniwaki, Masafumi

    2013-04-01

    Disseminated intravascular coagulation (DIC) is a life-threatening complication, and its control is essential for therapeutic success. Recombinant human soluble thrombomodulin alfa (rTM) is a novel therapeutic agent for DIC. The efficacy of rTM in the treatment of DIC is reportedly superior to that of conventional anti-DIC treatments, such as unfractionated heparin or low molecular weight heparin, but hemorrhagic events occasionally interfere with the therapeutic benefits of rTM. We assessed the clinical features of 20 consecutive patients who were given rTM for DIC associated with various hematologic disorders. Eight patients achieved remission of both primary disease and DIC, eight died due to progression of the primary disease, and four died of various hemorrhagic complications. Assessment of 16 biomarkers for coagulation showed that the four patients who died of hemorrhagic complications despite remission of their primary disease showed lower ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin Type 1 motif, member 13) plasma activity than other patients (P = 0.016). The optimal cut-off level of ADAMTS-13 for predicting risk of hemorrhagic complications was 42 % (P = 0.007). Plasma ADAMTS-13 activity determined at diagnosis of DIC may help predict the risk of hemorrhagic events during and/or following DIC treatment with hematologic disorders.

  11. Removal of humic and tannic acids by adsorption-coagulation combined systems with activated biochar.

    PubMed

    Jung, Chanil; Phal, Narong; Oh, Jeill; Chu, Kyoung Hoon; Jang, Min; Yoon, Yeomin

    2015-12-30

    Despite recent interest in transforming biomass into bio-oil and syngas, there is inadequate information on the compatibility of byproducts (e.g., biochar) with agriculture and water purification infrastructures. A pyrolysis at 300°C yields efficient production of biochar, and its physicochemical properties can be improved by chemical activation, resulting in a suitable adsorbent for the removal of natural organic matter (NOM), including hydrophobic and hydrophilic substances, such as humic acids (HA) and tannic acids (TA), respectively. In this study, the adsorption affinities of different HA and TA combinations in NOM solutions were evaluated, and higher adsorption affinity of TA onto activated biochar (AB) produced in the laboratory was observed due to its superior chemisorption tendencies and size-exclusion effects compared with that of HA, whereas hydrophobic interactions between adsorbent and adsorbate were deficient. Assessment of the AB role in an adsorption-coagulation hybrid system as nuclei for coagulation in the presence of aluminum sulfate (alum) showed a synergistic effect in a HA-dominated NOM solution. An AB-alum hybrid system with a high proportion of HA in the NOM solution may be applicable as an end-of-pipe solution. PMID:26340547

  12. Murine schistosomiasis mansoni: process of blood coagulation at pre-patent, acute and chronic phases, and consequence of chemotherapeutic cure on the reversion of changes.

    PubMed

    Carvalho, Maria G; Mello, Rômulo T; Soares, Anna L; Bicalho, Rosilene S; Lima e Silva, Francisco C; Coelho, Paulo M Z

    2005-10-01

    The present study aims to elucidate in a sequential manner the changes of the blood coagulation process at different phases of experimental schistosomiasis, comprising the pre-patent, acute, intermediate and chronic phases, and the effect of chemotherapeutic cure, at the acute and chronic phases, on reversion of changes related to the coagulation factors. Mice were infected with Schistosoma mansoni cercariae, and were divided into four groups. Blood samples from these groups were collected 32, 70, 100, and 140 days after infection, corresponding to the pre-patent, acute, intermediate and chronic phases, respectively. Simultaneously, other infected groups were given oxamniquine, 70 and 140 days after infection. At the same time as blood collection from infected and/or treated animal groups, other uninfected control animal groups were punctured and maintained under the same conditions as the infected animals. The vitamin-K-dependent clotting factors were found to be more sensitive to infection at different phases, while factors VIII and XI presented hyperactivity. Results obtained 90 days after chemotherapeutic treatment with oxamniquine, administered at the acute and chronic phases, presented noticeable reversion of the main alterations in the coagulation mechanism. The present study provides unquestionable data on the development of hemostatic changes throughout the course of S. mansoni infection.

  13. Systemic heparinization during peripheral vascular surgery: thromboelastographic, activated coagulation time, and heparin titration monitoring.

    PubMed

    Martin, P; Greenstein, D; Gupta, N K; Walker, D R; Kester, R C

    1994-04-01

    Fifteen patients (9 male, 6 female) undergoing peripheral vascular surgery were monitored during surgery for evidence of subclinical anticoagulation using the activated coagulation time (ACT), thromboelastography (TEG), and heparin titration monitoring. Assessments were made at 30-minute intervals before and after the occlusion clamp. Mean (+/- SD) ACT values preoperatively were 111 (17) seconds, and 10 minutes after 5,000 IU of heparin, the ACT was 264 (57) seconds (P < 0.001). Intraoperatively, there was a significant decline in ACT values at 30 minutes (ACT 228 [50] sec, P < 0.005) and 60 minutes (200 [46] sec, P < 0.001) postheparin. No significant difference in ACT was observed between samples drawn distally and proximally to the clamp. TEG profiles were abolished in all patients immediately following heparinization. However, in 2 patients nearly complete return of the TEG coagulation profile was observed prior to the termination of the procedure and was associated with ACT values less than 160 seconds. The heparin device was unable to accurately monitor heparin elimination at these low doses. Variability of patient response to heparinization necessitates the use of intraoperative monitoring of anticoagulation during peripheral vascular surgery.

  14. Lipids and blood coagulation studies in women using steroidal hormones for contraception.

    PubMed

    Hashmi, J A; Kazi, A B; Kazi, A; Ali, N

    1972-08-01

    The experimental group in this study at the Family Planning Clinic, Jinnah Postgraduate Medical Centre in Karachi, Pakistan consisted of 23 women who had been taking Ovral-28 (oral, .5 mg norgestrel, .05 mg ethinyl estradiol) and 27 women who had been receiving Depoprovera (intramuscular injection every 6 months of 300 mg Medroxy Progesterone Acetate). The 26 controls were clinic newcomers seeking contraceptive advice. Venous blood was obtained from each subject, and estimates were made of total cholesterol, triglycerides, prothrombin time, partial thromboplastin time, euglobulin clot lysis time, and plasma fibrinogen. The women were grouped according to therapy and its length (less than 3 months, 4 months-1 year, and more than 1 year). No significant differences were shown through most of the tests. Except for the women who had received Depoprovera for 4 months-1 year, plasma fibrinogen was significantly elevated (p less than .05) in all treated women. The euglobuli CLOTS LYSIS TIME WAS SIGNIFICANTLY LONGER (P .01) IN WOMEN ON Ovral-28 for 4 months-1 year. It had been suggested that the high prevalence of anemia in Pakistani women protects them against thrombotic complications. On the other hand, most treated subjects in this study were nonanemic, while their lipids had no significant increase.

  15. The coagulation system and its function in early immune defense.

    PubMed

    van der Poll, Tom; Herwald, Heiko

    2014-10-01

    Blood coagulation has a Janus-faced role in infectious diseases. When systemically activated, it can cause serious complications associated with high morbidity and mortality. However, coagulation is also part of the innate immune system and its local activation has been found to play an important role in the early host response to infection. Though the latter aspect has been less investigated, phylogenetic studies have shown that many factors involved in coagulation have ancestral origins which are often combined with anti-microbial features. This review gives a general overview about the most recent advances in this area of research also referred to as immunothrombosis.

  16. Coagulation studies.

    PubMed

    Hazelzet, J A; Hack, C E; de Groot, R

    2001-01-01

    Disseminated intravascular coagulation (DIC) is a complex acquired, coagulopathy resulting from excessive thrombin formation. Abnormal tissue factor (TF) expression is a major mechanism initiating DIC in many disorders, including obstetric complications, sepsis, cancer, and trauma. Numerous laboratory tests are available to monitor DIC, but most patients can be adequately managed using only routine hemostasis screening tests, and assays for fibrinogen and D-dimers. Treatment of DIC should focus on reversing the underlying disorder that initiated the coagulopathy. Novel treatments are being investigated for the treatment of DIC; many of these experimental modalities target the excessive TF activity that characterizes DIC.

  17. Extrinsic blood coagulation pathway and risk factors for thrombotic events in patients with essential thrombocythemia.

    PubMed

    Stankowska, Katarzyna; Gadomska, Grażyna; Boinska, Joanna; Michalska, Małgorzata; Bartoszewska-Kubiak, Alicja; Rość, Danuta

    2016-05-31

    INTRODUCTION    The clinical course of essential thrombocythemia (ET) is varied, and some patients do not exhibit any clinical signs of the disease at the time of diagnosis. The most frequent complications that occur during the course of ET are hemostasis abnormalities manifesting as hemorrhagic or thrombotic events. The mechanism of thrombotic events in patients with ET is complex and not fully understood. OBJECTIVES    The aim of the study was to evaluate the concentration and activity of tissue factor (TF) and tissue factor pathway inhibitor (TFPI), depending on the most important risk factors of thrombotic complications (age >60 years, history of thrombotic episodes, presence or absence of the JAK2 V617F mutation, and increased leukocyte count). PATIENTS AND METHODS    The study group included 113 patients with diagnosed ET, and the control group, 30 healthy volunteers matched for age and sex. The concentration and activity of TF and TFPI were measured using enzyme-linked immunosorbent assays. RESULTS    Patients with ET had a significantly higher activity and concentration of TF and increased activity of TFPI, as compared with controls. The analysis of the studied parameters in relation to risk factors revealed that patients with ET with a history of thrombotic events had a significantly higher concentration of TF, and patients with the JAK2 V617F mutation had a lower TFPI activity, as compared with patients without the mutation. CONCLUSIONS    Our study showed that in patients with ET who have a history of thrombosis or the JAK2 V617F mutation, the enhanced risk of thrombosis may result from an increased TF concentration or decreased TFPI activity. PMID:27243342

  18. Measurement of dabigatran in standardly used clinical assays, whole blood viscoelastic coagulation, and thrombin generation assays.

    PubMed

    van Ryn, Joanne; Grottke, Oliver; Spronk, Henri

    2014-09-01

    Dabigatran, a direct thrombin inhibitor, is increasingly used clinically as one of the new oral anticoagulants. This review summarizes the assays available to measure its activity and includes the relative sensitivity of the different assays for this agent. In addition to plasma-based clotting tests, assays commonly used in surgical/emergency settings, such as activated clotting time and thromboelastometry/thromboelastography, are reviewed. In addition, the thrombin generation assay is discussed as an important method to determine the potential risk of thrombosis or bleeding and its relevance to the measurement of direct thrombin inhibitors. PMID:25168938

  19. Influence of synoptic processes on fibrinolysis and fibrinogenolysis in healthy persons. [meteorological effects on blood coagulation

    NASA Technical Reports Server (NTRS)

    Marchenko, V. I.

    1974-01-01

    It is shown that on days with frontal activity in the atmosphere the levels of fibrinolysis and fibrinogenolysis are increased. The reactions of fibrinolysis and fibrinogenolysis to the passage of warm and cold fronts varies with the season of the year.

  20. Evaluation of the treatment of reverse osmosis concentrates from municipal wastewater reclamation by coagulation and granular activated carbon adsorption.

    PubMed

    Sun, Ying-Xue; Yang, Zhe; Ye, Tao; Shi, Na; Tian, Yuan

    2016-07-01

    Reverse osmosis concentrate (ROC) from municipal wastewater reclamation reverse osmosis (mWRRO) contains elevated concentrations of contaminants which pose potential risks to aquatic environment. The treatment of ROC from an mWRRO using granular activated carbon (GAC) combined pretreatment of coagulation was optimized and evaluated. Among the three coagulants tested, ferric chloride (FeCl3) presented relatively higher DOC removal efficiency than polyaluminium chloride and lime at the same dosage and coagulation conditions. The removal efficiency of DOC, genotoxicity, and antiestrogenic activity concentration of the ROC could achieve 16.9, 18.9, and 39.7 %, respectively, by FeCl3 coagulation (with FeCl3 dosage of 180.22 mg/L), which can hardly reduce UV254 and genotoxicity normalized by DOC of the DOM with MW <5 kDa. However, the post-GAC adsorption column (with filtration velocity of 5.7 m/h, breakthrough point adsorption capacity of 0.22 mg DOC/g GAC) exhibited excellent removal efficiency on the dominant DOM fraction of MW <5 kDa in the ROC. The removal efficiency of DOC, UV254, and TDS in the ROC was up to 91.8, 96, and 76.5 %, respectively, by the FeCl3 coagulation and post-GAC adsorption. Also, the DOM with both genotoxicity and antiestrogenic activity were completely eliminated by the GAC adsorption. The results suggest that GAC adsorption combined pretreatment of FeCl3 coagulation as an efficient method to control organics, genotoxicity, and antiestrogenic activity in the ROC from mWRRO system. PMID:27032632

  1. Evaluation of the treatment of reverse osmosis concentrates from municipal wastewater reclamation by coagulation and granular activated carbon adsorption.

    PubMed

    Sun, Ying-Xue; Yang, Zhe; Ye, Tao; Shi, Na; Tian, Yuan

    2016-07-01

    Reverse osmosis concentrate (ROC) from municipal wastewater reclamation reverse osmosis (mWRRO) contains elevated concentrations of contaminants which pose potential risks to aquatic environment. The treatment of ROC from an mWRRO using granular activated carbon (GAC) combined pretreatment of coagulation was optimized and evaluated. Among the three coagulants tested, ferric chloride (FeCl3) presented relatively higher DOC removal efficiency than polyaluminium chloride and lime at the same dosage and coagulation conditions. The removal efficiency of DOC, genotoxicity, and antiestrogenic activity concentration of the ROC could achieve 16.9, 18.9, and 39.7 %, respectively, by FeCl3 coagulation (with FeCl3 dosage of 180.22 mg/L), which can hardly reduce UV254 and genotoxicity normalized by DOC of the DOM with MW <5 kDa. However, the post-GAC adsorption column (with filtration velocity of 5.7 m/h, breakthrough point adsorption capacity of 0.22 mg DOC/g GAC) exhibited excellent removal efficiency on the dominant DOM fraction of MW <5 kDa in the ROC. The removal efficiency of DOC, UV254, and TDS in the ROC was up to 91.8, 96, and 76.5 %, respectively, by the FeCl3 coagulation and post-GAC adsorption. Also, the DOM with both genotoxicity and antiestrogenic activity were completely eliminated by the GAC adsorption. The results suggest that GAC adsorption combined pretreatment of FeCl3 coagulation as an efficient method to control organics, genotoxicity, and antiestrogenic activity in the ROC from mWRRO system.

  2. Total Cavopulmonary Connection is Superior to Atriopulmonary Connection Fontan in Preventing Thrombus Formation: Computer Simulation of Flow-Related Blood Coagulation.

    PubMed

    Sughimoto, Koichi; Okauchi, Kazuki; Zannino, Diana; Brizard, Christian P; Liang, Fuyou; Sugawara, Michiko; Liu, Hao; Tsubota, Ken-Ichi

    2015-10-01

    The classical Fontan route, namely the atriopulmonary connection (APC), continues to be associated with a risk of thrombus formation in the atrium. A conversion to a total cavopulmonary connection (TCPC) from the APC can ameliorate hemodynamics for the failed Fontan; however, the impact of these surgical operations on thrombus formation remains elusive. This study elucidates the underlying mechanism of thrombus formation in the Fontan route by using a two-dimensional computer hemodynamic simulation based on a simple blood coagulation rule. Hemodynamics in the Fontan route was simulated with Navier-Stokes equations. The blood coagulation and the hemodynamics were combined using a particle method. Three models were created: APC with a square atrium, APC with a round atrium, and TCPC. To examine the effects of the venous blood flow velocity, the velocity at rest and during exercise (0.5 and 1.0 W/kg) was measured. The total area of the thrombi increased over time. The APC square model showed the highest incidence for thrombus formation, followed by the APC round, whereas no thrombus was formed in the TCPC model. Slower blood flow at rest was associated with a higher incidence of thrombus formation. The TCPC was superior to the classical APC in terms of preventing thrombus formation, due to significant blood flow stagnation in the atrium of the APC. Thus, local hemodynamic behavior associated with the complex channel geometry plays a major role in thrombus formation in the Fontan route.

  3. Integrated membrane systems incorporating coagulation, activated carbon and ultrafiltration for the removal of toxic cyanobacterial metabolites from Anabaena circinalis.

    PubMed

    Dixon, M B; Richard, Y; Ho, L; Chow, C W K; O'Neill, B K; Newcombe, G

    2011-01-01

    The use of integrated membrane systems (a train of treatment processes incorporating one or more membranes) is increasing globally as the technology is very effective for the production of high quality drinking water. In this investigation a laboratory scale integrated membrane system (IMS) featuring coagulation, powdered activated carbon (PAC) and ultrafiltration (UF) was investigated for the removal of an Australian strain of the cyanobacteria Anabaena circinalis and the cyanotoxin it produced. Three coagulants were compared, aluminium chlorohydrate (ACH), aluminium sulphate (alum) and an engineered aluminium coagulant referred to as high performance aluminium chlorohydrate (HPAC). PAC (Acticarb PS1000) was tested to determine adsorption of extracellular saxitoxin. Removal of A. circinalis cells was 100% by UF alone and the removal of cells prior to the membrane by coagulation reduced fouling attributed to algogenic organic material. Alum was the least efficient coagulant for removal of cells while ACH and HPAC were similar. Saxitoxin removal reached a maximum of 80% using ACH and PAC. The UF-IMS was challenged using a natural bloom of A. circinalis that occurred in the Myponga Reservoir in South Australia. PMID:21508543

  4. Silver nanoparticles influence on the blood activation process and their release to blood plasma from synthetic polymer scaffold

    NASA Astrophysics Data System (ADS)

    Major, R.; Lackner, J. M.; Sanak, M.; Major, B.

    2016-03-01

    In the present work, blood and blood plasma interaction to silver stabilised polyelectrolytes was investigated in vitro. The designed materials are dedicated for regeneration of the cardiovascular system. Silver nanoparticles were introduced into the polyelectrolyte structure in order to reduce the risk of bacterial biofilm formation. The introduction of Ag nanoparticles occurred by deposition at high vacuum by magnetron sputtering. The analysis of blood-materials interactions were performed by using commercially available tester, Impact-R (Diamed). The assessment of silver ion nanoparticles release into the plasma consisted in determining the Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT). Unmodified surface of polyelectrolytes is a strong activator for blood elements. The introduction of silver nanoparticles resulted in a significant reduction in the probability of clotting. The extrinsic pathway of coagulation determined on the basis of the PT and the intrinsic and common pathways of coagulation measured by the APTT did not indicate the danger out of range. Microstructure was studied using TEM on thin foils prepared from the cross-section of samples subjected to biomedical treatments. The observations revealed hetero- interface between two different crystalline solids.

  5. [Perioperative management of coagulation and fibrinolytic activity in endosaccular embolization of cerebral aneurysms].

    PubMed

    Nakahara, I; Taki, W; Tanaka, M; Sadatou, A; Matsumoto, K; Kikuchi, H

    1994-05-01

    Endosaccular embolization is an innovative and effective treatment for surgically formidable cerebral aneurysms. Platinum microcoils are soft, easily fit to complex configuration of aneurysms, highly thrombogenic, so that suitable for this purpose. Recently developed Guglielmi detachable coils have more advantages in terms of retrievability and electrothrombotic effect. However, distal migration of intraaneurysmal thrombus produces thromboembolism in normal cerebral arteries, leading to neurological deficits. Three cases are presented in which thromboembolic complications occurred during or after embolization of cerebral aneurysms with platinum microcoils. Emergent fibrinolytic treatment resolved neurological deficits in each case without any other complications. From these lessons, a protocol of intra- and postoperative anticoagulation and antiplatelet therapy is presented. In conclusion, perioperative management of fibrinolytic and coagulation activity is extremely important in preventing thromboembolic complication and obtaining successful result.

  6. Dynamics of change of lipid and monoamine metabolisms and the blood coagulation system during experimental atherosclerosis caused by restriction of movement

    NASA Technical Reports Server (NTRS)

    Gvishiani, G. S.; Kobakhidze, N. G.

    1980-01-01

    Shifts in lipid, catecholamine, and blood coagulation systems following various periods (1, 2, 3, and 4 months) of experimentally induced atherosclerosis were studied. The same indices were studied in the tissues of the myocardium, liver, and brain stem-reticular formation after decapitation of the animals at the end of the experiment. Periodic motion restriction caused an increase in blood beta-lipoproteins in the rabbits at the beginning of the experiment. An increase in general cholesterol content and a decrease in the lecithincholesterol index were established at the end of the experiment. Myocardial beta-lipoprotein and brain stem reticular formation general cholesterol contents were elevated; catecholamine content was increased at the end of the experiment. In the initial months, free adrenaline basically increased, while in later months blood adrenaline decreased and blood noradrenaline increased.

  7. Poly-2-methoxyethylacrylate-coated bypass circuits reduce activation of coagulation system and inflammatory response in congenital cardiac surgery.

    PubMed

    Suzuki, Yasuyuki; Daitoku, Kazuyuki; Minakawa, Masahito; Fukui, Kozo; Fukuda, Ikuo

    2008-01-01

    Surface-coated cardiopulmonary bypass (CPB) has been shown to have excellent biocompatibility during cardiac surgery in adults, but there have been only a few reports demonstrating the efficacy of this coating for congenital cardiac surgery. We tested the efficacy of poly-2-methoxyethylacrylate (PMEA) coating for CPB circuits in congenital cardiac surgery. Eleven operative cases of ventricular septal defect were studied: group C (control: no coating, n = 5) and group P (PMEA coating, n = 6). The platelet count and beta-thromboglobulin (beta TG), fibrinogen (FBG), thrombin-antithrombin complex (TAT), and neutrophil elastase levels were measured during the operation. Postoperative chest tube drainage was analyzed and the surface of the artificial lung was observed with an electron microscope. Elevation of TAT and neutrophil elastase was suppressed in group P (P < 0.05). Observation of the artificial lung surface using an electron microscope clearly revealed fewer blood cells were adherent to the surface in group P. The FBG level and postoperative bleeding were relatively lower in group P, but there were no significant differences between groups. The platelet count and beta TG level were the same in both groups. We concluded that the PMEA-coated circuit reduces activation of the coagulation system and the inflammatory reaction in pediatric cardiac surgery.

  8. Revisiting the mechanism of coagulation factor XIII activation and regulation from a structure/functional perspective

    PubMed Central

    Gupta, Sneha; Biswas, Arijit; Akhter, Mohammad Suhail; Krettler, Christoph; Reinhart, Christoph; Dodt, Johannes; Reuter, Andreas; Philippou, Helen; Ivaskevicius, Vytautas; Oldenburg, Johannes

    2016-01-01

    The activation and regulation of coagulation Factor XIII (FXIII) protein has been the subject of active research for the past three decades. Although discrete evidence exists on various aspects of FXIII activation and regulation a combinatorial structure/functional view in this regard is lacking. In this study, we present results of a structure/function study of the functional chain of events for FXIII. Our study shows how subtle chronological submolecular changes within calcium binding sites can bring about the detailed transformation of the zymogenic FXIII to its activated form especially in the context of FXIIIA and FXIIIB subunit interactions. We demonstrate what aspects of FXIII are important for the stabilization (first calcium binding site) of its zymogenic form and the possible modes of deactivation (thrombin mediated secondary cleavage) of the activated form. Our study for the first time provides a structural outlook of the FXIIIA2B2 heterotetramer assembly, its association and dissociation. The FXIIIB subunits regulatory role in the overall process has also been elaborated upon. In summary, this study provides detailed structural insight into the mechanisms of FXIII activation and regulation that can be used as a template for the development of future highly specific therapeutic inhibitors targeting FXIII in pathological conditions like thrombosis. PMID:27453290

  9. Coagulation activation after discontinuation of VTE treatment with different oral anticoagulants and impact on 12-month clinical outcomes.

    PubMed

    Beyer-Westendorf, Jan; Gehrisch, Siegmund; Stange, Thoralf; Tittl, Luise; Siegert, Gabriele; Weiss, Norbert

    2015-08-01

    Increasing D-dimer (DD) levels after discontinuation of vitamin K antagonist (VKA) therapy indicate an increased risk of recurrence of venous thromboembolism (VTE). However, after discontinuation of direct-acting non-VKA oral anticoagulants (DOACs or NOACs) the extent of coagulation activation and its clinical impact is unknown. Blood samples were collected from consenting patients with proximal VTE at the end of anticoagulation treatment with apixaban (n=37), dabigatran (n=17), rivaroxaban (n=9) or VKA (n=184) and 4weeks later. DD, prothrombin fragments F1+2 (F1+2) and thrombin-antithrombin complexes (TAT) were measured. All patients underwent follow-up at 12months to establish recurrent VTE or death from any cause. Irrespective of the treatment, DD and F1+2 but not TAT demonstrated a similar increase between baseline and week 4. At 12months, 18 patients (7.3%) had recurrent VTE and two (0.8%) had died. For all patients and subgroups of VKA and DOAC, positive likelihood ratios were numerically higher for baseline values but only TAT values at 4weeks were found to be related to a small increase of outcome event likelihood (2.6; 95%CI 1.23-5.50), which was driven by VKA patients (3.1; 95%CI 1.32-7.30) and not by DOAC patients (2.27; 95%CI 0.52-9.95). For all parameters, negative likelihood ratios were not predictive. In logistic regression analysis, only ΔTAT (optimal cut-off >178% from baseline demonstrated a significant risk increase for VTE/death (odds ratio 3.76; 95% confidence interval 1.46-9.68; p=0.006). In conclusion, the concept of testing coagulation activation parameters may also be transferred to VTE patients at the end of DOAC therapy. For patients with an increase of TAT levels within 4weeks after treatment discontinuation (>178% from baseline) is associated with an increased risk for VTE recurrence or death at 12months.

  10. Treatment of Disseminated Intravascular Coagulation.

    PubMed

    Makruasi, Nisa

    2015-11-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic activation of blood coagulation, generation of thrombin, and leading to disturbance of the microvasculature. In this article, definition and diagnostic criteria of DIC depend on the International Society of Thrombosis and Haemostasis (ISTH). There is no gold standard for diagnosis of DIC, only low quality evidence is used in general practice. Many diagnostic tests and repeated measurement are required. For the treatment of DIC, there is no good quality evidence. The most important treatment for DIC is the specific treatment of the conditions associated DIC. Platelets and/or plasma transfusion may be also necessary if indicated. Nevertheless, there is no gold standard for diagnosis and treatment of DIC, we use only low quality evidence in general practice.

  11. Antibodies against oxidized phospholipids in laboratory tests exploring lupus anti-coagulant activity

    PubMed Central

    Rolla, R; Vidali, M; Serino, R; Pergolini, P; Albano, E; Bellomo, G

    2007-01-01

    Lupus anti-coagulants (LA) are a variety of anti-phospholipid antibodies characterized by their capacity to interfere with phospholipid-dependent coagulation assays. LA are increasingly recognized as important predictors of thrombosis. However, the antigen specificity of LA is still poorly characterized. Growing evidence indicates that oxidized phospholipids are among the targets of anti-phospholipid antibodies. This prompted us to investigate the role of IgG directed against different oxidized phospholipids in 164 subjects without clotting factor defects that were tested for the presence of LA using a LA-sensitive activate partial thromboplastin time (aPTT-FSL) and a screening/confirmation assay based on diluted Russell's viper venom test (dRVVT-PL). The response to aPTT-FSL was significantly (P < 0·0005) associated with high titres of IgG against oxidized phosphatidylserine, phosphatidylethanolamine and phosphatidylinositol, whereas positivity to dRVVT-PL was associated with the elevation of IgG against oxidized phosphatidylserine, phosphatidylcholine, phosphatidylethanolamine (P < 0·0005) and phosphatidylinositol (P < 0·01). No difference in reactivity against oxidized cardiolipin was evident between the different groups. Positivity to the dRVVT-PL test was also associated significantly (P < 0·005) with the elevation of anti-cardiolipin and anti-β2-glycoprotein-1 IgG. However, stepwise logistic regression demonstrated that IgG recognizing oxidized phosphatidylethanolamine and oxidized phosphatidylcholine were the only independent predictors of the response to dRVVT-PL assay, while IgG recognizing oxidized phosphatidylethanolamine and oxidized phosphatidylinositol were independent predictors of the response to aPTT-FSL test. In conclusion, autoantibodies against defined oxidized phospholipids are independent predictors of LA detection by aPTT-FSL or dRVVT-PL assays and might contribute to the variability often observed in the responses to the functional

  12. Activation of the contact system of coagulation by a monoclonal antibody directed against a neodeterminant in the heavy chain region of human coagulation factor XII (Hageman factor).

    PubMed

    Nuijens, J H; Huijbregts, C C; Eerenberg-Belmer, A J; Meijers, J C; Bouma, B N; Hack, C E

    1989-08-01

    We studied the characteristics of two monoclonal antibodies (mAbs), F1 and F3, against human coagulation factor XII (Hageman factor). Experiments with trypsin-digested 125I-factor XII revealed that the epitope for mAb F1 is located in the NH2-terminal Mr 40,100 portion of factor XII, whereas that for mAb F3 resides in the COOH-terminal Mr 30,000 portion of this protein. Factor XII in fresh plasma (single-chain factor XII) bound approximately 190 times less to mAb F1 than factor XII in dextran sulfate-activated plasma (cleaved factor XII). However, no difference in accessibility of the epitope for mAb F1 was observed between cleaved and single-chain factor XII when bound to glass. mAb F3 appeared to bind to both single-chain and cleaved factor XII in plasma as well as when bound to glass. Neither mAb F1, nor F3 affected the amidolytic activity of factor XIIa, whereas both mAb F1 and F3 inhibited factor XII-coagulant activity to about 15 and 70%, respectively, at a molar ratio of mAb to factor XII of 20 to 1. mAb F1, as well as F(ab')2 and F(ab') fragments of this antibody induced activation of the contact system in plasma, as reflected by the generation of factor XIIa. C1 inhibitor and kallikrein. C1 inhibitor complexes. Activation was induced neither upon incubation with mAb F3, nor with that of control mAbs. mAb F1-induced contact activation required the presence of factor XII, prekallikrein, and high molecular weight kininogen and, in contrast to activation by negatively charged surfaces, was not inhibited by the presence of Polybrene. Based on these results we propose that a conformational change in factor XII is a key event in the activation process of this molecule. This conformational change can be induced by binding of factor XII to a surface as well as by proteolytic cleavage. As mAb F1 can also induce this conformational change, this antibody may provide a unique tool in studies of the activation of factor XII.

  13. The long-term effects of the rodenticide, brodifacoum, on blood coagulation and vitamin K metabolism in rats.

    PubMed Central

    Mosterd, J. J.; Thijssen, H. H.

    1991-01-01

    1. The long-term (30 days) effects of a single dose of brodifacoum (0.2 mg kg-1, orally) on blood clotting activity and on liver parameters of the vitamin K cycle were investigated in rats. Maximal effect on blood clotting activity was seen on day one. On day seven blood clotting activity had returned to normal. 2. Liver microsomal vitamin KO reductase activity was maximally suppressed (10% of control activity) on day one, steadily recovered to about 40% on day 15 to remain at that level. The same time course was seen for the number of microsomal warfarin binding sites. 3. The persistent inhibition of the vitamin K cycle was also verified in vivo; following vitamin K administration (10 mg kg-1, i.v.) on day 30, the brodifacoum-treated rats accumulated vitamin KO in the liver. 4. Although clotting factor synthesis was normal, brodifacoum-treated rats were highly sensitive to warfarin. 5. Brodifacoum rapidly accumulated in the liver until the saturation of the microsomal binding site. Brodifacoum binding to the target prevented its elimination from the liver; liver content on day 30 was not different from day 7. 6. The results show (1) an over capacity for the hepatocellular vitamin K cycle, (2) a dissociation of the vitamin K epoxidation and the vitamin K-dependent carboxylation, (3) the 'superwarfarin' rodenticides to be extremely persistent due to their binding to the target. PMID:1797316

  14. Determination of tumor cell procoagulant activity by Sonoclot analysis in whole blood.

    PubMed

    Amirkhosravi, A; Biggerstaff, J P; Warnes, G; Francis, D A; Francis, J L

    1996-12-01

    Coagulation activation in cancer may be due to expression of procoagulant activity (PCA) by tumor cells. Some PCA activate coagulation, while others influence platelet aggregation. Thus, clotting time assessments of PCA may not reflect the potential for hypercoagulability. We therefore studied the effect of various malignant and non-malignant cells on whole blood coagulation using the Sonoclot Analyzer. Five human (HT29 colon, J82 bladder, MCF-7 breast, BT-474 breast and A375 malignant melanoma) and three rodent (MC28, WEHI-164 and Neuro2a) cell lines were used. Rat thymocytes and peritoneal macrophages and human endotoxin-stimulated mononuclear cells and umbilical vein endothelial cells (HUVEC) were used as non-malignant controls. All tumor cells markedly shortened the recalcification time of citrated blood and the most potent (HT29 and J82) also increased clot rate (P < 0.01). The breast cancer cells MCF-7 and BT-474 expressed only weak PCA and did not affect clotting rate. None of the non-malignant cells significantly affected clotting time or rate in whole blood. J82 and HT29 cells grown in serum-rich media shortened the recalcification time of both normal and FVII-deficient plasmas. However, cells grown in serum-free conditions had significantly less PCA in FVII-deficient plasma. We conclude that the Sonoclot Analyzer is useful for determining cellular PCA; significant PCA is a feature of malignant cells and cells grown in medium containing serum supplements cannot be reliably evaluated for PCA.

  15. [Comparative blood coagulation studies in PGF2a- and 15-methyl-PGF2a-induced therapeutic abortion].

    PubMed

    During, R; Junge, W D; Klausch, B

    1980-01-01

    In 15 pregnant women of the first trimenon of gravidity an interruption was performed by means of extra-amnial application of PGF2a and in 10 pregnant women by means of i. m. application of 15-methyl-PGF2a. Bleeding time, recalcification time, number of thrombocytes, heat fibrin, and thrombocyte adhesiveness were determined before, during and after treatment. Statistically significant changes could be observed during bleeding time, heat fibrin, and thrombocyte number. The investigations of coagulation, however, did not reveal any considerable impairment of the coagulation system, thus confirming the positive evaluation of prostaglandines used for therapeutic induction of abortion.

  16. Activation of the complement, coagulation, fibrinolytic and kallikrein-kinin systems during attacks of hereditary angioedema.

    PubMed

    Nielsen, E W; Johansen, H T; Høgåsen, K; Wuillemin, W; Hack, C E; Mollnes, T E

    1996-08-01

    Five patients with hereditary angioedema (HAE) were studied during attacks and remission as were healthy controls. The high levels of C1/C1-INH complexes, low C4 and high ratio C4 activation products (C4bc)/C4 also differed significantly during remission compared to controls. During attacks C4bc/C4 increased (922-2007; P = 0.022, remission versus attacks, median values throughout), C2 and CH50 dropped (111-31%; P = 0.043 and 110-36%; P = 0.016, respectively), TCC (C5b-9) increased (0.88-1.23 AU/ml; P = 0.028). Cleavage of HK increased to be almost complete during attacks (20-90%; P = 0.009). While factor XIa/serpin-complexes did not increase, a more than twofold rise in thrombin/antithrombin-complexes (0.20-0.50 microgram/l; P = 0.009) and in plasmin/alpha-2-antiplasmin-complexes (7.3-17 nmol/l; P = 0.028) was observed. For the first time cascade activation in HAE was studied simultaneously, and corroborates that attacks lead to activation of the kallikrein-kinin system, fibrinolysis and early part of the classical complement pathway. In addition, the authors present novel data of terminal complement and coagulation activation, the latter apparently not via FXIa.

  17. Combining Coagulation/MIEX with Biological Activated Carbon Treatment to Control Organic Fouling in the Microfiltration of Secondary Effluent

    PubMed Central

    Pramanik, Biplob Kumar; Roddick, Felicity A.; Fan, Linhua

    2016-01-01

    Coagulation, magnetic ion exchange resin (MIEX) and biological activated carbon (BAC) were examined at lab scale as standalone, and sequential pre-treatments for controlling the organic fouling of a microfiltration membrane by biologically treated secondary effluent (BTSE) using a multi-cycle approach. MIEX gave slightly greater enhancement in flux than coagulation due to greater removal of high molecular weight (MW) humic substances, although it was unable to remove high MW biopolymers. BAC treatment was considerably more effective for improving the flux than coagulation or MIEX. This was due to the biodegradation of biopolymers and/or their adsorption by the biofilm, and adsorption of humic substances by the activated carbon, as indicated by size exclusion chromatography. Coagulation or MIEX followed by BAC treatment further reduced the problematic foulants and significantly improved the flux performance. The unified membrane fouling index showed that the reduction of membrane fouling by standalone BAC treatment was 42%. This improved to 65%, 70%, and 93% for alum, ferric chloride and MIEX pre-treatment, respectively, when followed by BAC treatment. This study showed the potential of sequential MIEX and BAC pre-treatment for controlling organic fouling and thus enhancing the performance of microfiltration in the reclamation of BTSE. PMID:27483327

  18. Combining Coagulation/MIEX with Biological Activated Carbon Treatment to Control Organic Fouling in the Microfiltration of Secondary Effluent.

    PubMed

    Pramanik, Biplob Kumar; Roddick, Felicity A; Fan, Linhua

    2016-01-01

    Coagulation, magnetic ion exchange resin (MIEX) and biological activated carbon (BAC) were examined at lab scale as standalone, and sequential pre-treatments for controlling the organic fouling of a microfiltration membrane by biologically treated secondary effluent (BTSE) using a multi-cycle approach. MIEX gave slightly greater enhancement in flux than coagulation due to greater removal of high molecular weight (MW) humic substances, although it was unable to remove high MW biopolymers. BAC treatment was considerably more effective for improving the flux than coagulation or MIEX. This was due to the biodegradation of biopolymers and/or their adsorption by the biofilm, and adsorption of humic substances by the activated carbon, as indicated by size exclusion chromatography. Coagulation or MIEX followed by BAC treatment further reduced the problematic foulants and significantly improved the flux performance. The unified membrane fouling index showed that the reduction of membrane fouling by standalone BAC treatment was 42%. This improved to 65%, 70%, and 93% for alum, ferric chloride and MIEX pre-treatment, respectively, when followed by BAC treatment. This study showed the potential of sequential MIEX and BAC pre-treatment for controlling organic fouling and thus enhancing the performance of microfiltration in the reclamation of BTSE. PMID:27483327

  19. Combining Coagulation/MIEX with Biological Activated Carbon Treatment to Control Organic Fouling in the Microfiltration of Secondary Effluent.

    PubMed

    Pramanik, Biplob Kumar; Roddick, Felicity A; Fan, Linhua

    2016-07-30

    Coagulation, magnetic ion exchange resin (MIEX) and biological activated carbon (BAC) were examined at lab scale as standalone, and sequential pre-treatments for controlling the organic fouling of a microfiltration membrane by biologically treated secondary effluent (BTSE) using a multi-cycle approach. MIEX gave slightly greater enhancement in flux than coagulation due to greater removal of high molecular weight (MW) humic substances, although it was unable to remove high MW biopolymers. BAC treatment was considerably more effective for improving the flux than coagulation or MIEX. This was due to the biodegradation of biopolymers and/or their adsorption by the biofilm, and adsorption of humic substances by the activated carbon, as indicated by size exclusion chromatography. Coagulation or MIEX followed by BAC treatment further reduced the problematic foulants and significantly improved the flux performance. The unified membrane fouling index showed that the reduction of membrane fouling by standalone BAC treatment was 42%. This improved to 65%, 70%, and 93% for alum, ferric chloride and MIEX pre-treatment, respectively, when followed by BAC treatment. This study showed the potential of sequential MIEX and BAC pre-treatment for controlling organic fouling and thus enhancing the performance of microfiltration in the reclamation of BTSE.

  20. Effects of Blood Flow and/or Ventilation Restriction on Radiofrequency Coagulation Size in the Lung: An Experimental Study in Swine

    SciTech Connect

    Anai, Hiroshi; Uchida, Barry T.; Pavcnik, Dusan Seong, Chang Kyu; Baker, Phillip; Correa, Luiz Otavio; Corless, Christopher L.; Sakaguchi, Hiroshi; Kichikawa, Kimihiko; Keller, Frederick S.; Roesch, Josef

    2006-10-15

    The purpose of this study was to investigate how the restriction of blood flow and/or ventilation affects the radiofrequency (RF) ablation coagulation size in lung parenchyma. Thirty-one RF ablations were done in 16 normal lungs of 8 living swine with 2-cm LeVeen needles. Eight RF ablations were performed as a control (group G1), eight with balloon occlusion of the ipsilateral mainstem bronchus (G2), eight with occlusion of the ipsilateral pulmonary artery (G3), and seven with occlusion of both the ipsilateral bronchus and pulmonary artery (G4). Coagulation diameters and volumes of each ablation zone were compared on computed tomography (CT) and gross specimen examinations. Twenty-six coagulation zones were suitable for evaluation: eight in G1, five in G2, seven in G3, and six in G4 groups. In G1, the mean coagulation diameter was 21.5 {+-} 3.5 mm on CT and 19.5 {+-} 1.78 mm on gross specimen examination. In G2, the mean diameters were 26.5 {+-} 5.1 mm and 23.0 {+-} 2.7 mm on CT and gross specimen examination, respectively. In G3, the mean diameters were 29.4 {+-} 2.2 mm and 27.4 {+-} 2.9 mm on CT and gross specimen examination, respectively, and in G4, they were 32.6 {+-} 3.33 mm and 28.8 {+-} 2.6 mm, respectively. The mean coagulation volumes were 3.39 {+-} l.52 cm{sup 3} on CT and 3.01 {+-} 0.94 cm{sup 3} on gross examinations in G1, 6.56 {+-} 2.47 cm{sup 3} and 5.22 {+-} 0.85 cm{sup 3} in G2, 10.93 {+-} 2.17 cm{sup 3} and 9.97 {+-} 2.91 cm{sup 3} in G3, and 13.81 {+-} 3.03 cm{sup 3} and 11.06 {+-} 3.27 cm{sup 3} in G4, respectively. The mean coagulation diameters on gross examination and mean coagulation volumes on CT and gross examination with G3 and G4 were significantly larger than those in G1 (p < 0.0001, p < 0.0001, p < 0.0001, respectively) or in G2 (p < 0.05, p < 0.005, p < 0.005, respectively). Pulmonary collapse occurred in one lung in G2 and pulmonary artery thrombus in two lungs of G3 and two lungs of G4. The coagulation size of RF ablation of the

  1. Gas exchange and the coagulation system of the blood during the effect on the body of high concentrations of oxygen and carbon dioxide

    NASA Technical Reports Server (NTRS)

    Palosh, L.; Agadzhanyan, N. A.; Davydov, G. A.; Rybakov, B. K.; Sergiyenko, A. S.

    1974-01-01

    Maximum permissible concentrations of oxygen and carbon dioxide in a controlled atmosphere were determined by evaluating their effects on human gas exchange, blood coagulation, and tolerances to acute hypoxia, acceleration, and physical loads. It was found that functional disturbances depend on the concentration of respiratory gases and the length of stay in an altered atmosphere. By changing the atmospheric composition and by bringing the gaseous environment into accordance with the work and rest regimen and energy expenditures, the general reactivity of the body changes favorably.

  2. The Role of Putative Phosphatidylserine-Interactive Residues of Tissue Factor on Its Coagulant Activity at the Cell Surface

    PubMed Central

    Ansari, Shabbir A.; Pendurthi, Usha R.; Sen, Prosenjit; Rao, L. Vijaya Mohan

    2016-01-01

    Exposure of phosphatidylserine (PS) on the outer leaflet of the cell membrane is thought to play a critical role in tissue factor (TF) decryption. Recent molecular dynamics simulation studies suggested that the TF ectodomain may directly interact with PS. To investigate the potential role of TF direct interaction with the cell surface phospholipids on basal TF activity and the enhanced TF activity following the decryption, one or all of the putative PS-interactive residues in the TF ectodomain were mutated and tested for their coagulant activity in cell systems. Out of the 9 selected TF mutants, five of them -TFS160A, TFS161A, TFS162A, TFK165A, and TFD180A- exhibited a similar TF coagulant activity to that of the wild-type TF. The specific activity of three mutants, TFK159A, TFS163A, and TFK166A, was reduced substantially. Mutation of the glycine residue at the position 164 markedly abrogated the TF coagulant activity, resulting in ~90% inhibition. Mutation of all nine lipid binding residues together did not further decrease the activity of TF compared to TFG164A. A similar fold increase in TF activity was observed in wild-type TF and all TF mutants following the treatment of THP-1 cells with either calcium ionomycin or HgCl2, two agents that are commonly used to decrypt TF. Overall, our data show that a few select TF residues that are implicated in interacting with PS contribute to the TF coagulant activity at the cell surface. However, our data also indicate that TF regions outside of the putative lipid binding region may also contribute to PS-dependent decryption of TF. PMID:27348126

  3. A coagulation-powdered activated carbon-ultrafiltration--multiple barrier approach for removing toxins from two Australian cyanobacterial blooms.

    PubMed

    Dixon, Mike B; Richard, Yann; Ho, Lionel; Chow, Christopher W K; O'Neill, Brian K; Newcombe, Gayle

    2011-02-28

    Cyanobacteria are a major problem for the world wide water industry as they can produce metabolites toxic to humans in addition to taste and odour compounds that make drinking water aesthetically displeasing. Removal of cyanobacterial toxins from drinking water is important to avoid serious illness in consumers. This objective can be confidently achieved through the application of the multiple barrier approach to drinking water quality and safety. In this study the use of a multiple barrier approach incorporating coagulation, powdered activated carbon (PAC) and ultrafiltration (UF) was investigated for the removal of intracellular and extracellular cyanobacterial toxins from two naturally occurring blooms in South Australia. Also investigated was the impact of these treatments on the UF flux. In this multibarrier approach, coagulation was used to remove the cells and thus the intracellular toxin while PAC was used for extracellular toxin adsorption and finally the UF was used for floc, PAC and cell removal. Cyanobacterial cells were completely removed using the UF membrane alone and when used in conjunction with coagulation. Extracellular toxins were removed to varying degrees by PAC addition. UF flux deteriorated dramatically during a trial with a very high cell concentration; however, the flux was improved by coagulation and PAC addition. PMID:21227576

  4. Thrombomodulin/activated protein C system in septic disseminated intravascular coagulation.

    PubMed

    Ikezoe, Takayuki

    2015-01-01

    The thrombomodulin (TM)/activated protein C (APC) system plays an important role in maintaining the homeostasis of thrombosis and hemostasis and maintaining vascular integrity in vivo. TM expressed on vascular endothelium binds to thrombin, forming a 1:1 complex and acts as an anticoagulant. In addition, the thrombin-TM complex activates protein C to produce APC, which inactivates factors VIIIa and Va in the presence of protein S, thereby inhibiting further thrombin formation. Intriguingly, APC possesses anti-inflammatory as well as cytoprotective activities. Moreover, the extracellular domain of TM also possesses APC-independent anti-inflammatory and cytoprotective activities. Of note, the TM/APC system is compromised in disseminated intravascular coagulation (DIC) caused by sepsis due to various mechanisms, including cleavage of cell-surface TM by exaggerated cytokines and proteases produced by activated inflammatory cells. Thus, it is reasonable to assume that reconstitution of the TM/APC system by recombinant proteins would alleviate sepsis and DIC. On the basis of the success of the Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) trial, the FDA approved the use of recombinant human APC (rhAPC) for severe sepsis patients in 2002. However, subsequent clinical trials failed to show clinical benefits for rhAPC, and an increased incidence of hemorrhage-related adverse events was noted, which prompted the industry to withdraw rhAPC from the market. On the other hand, recombinant human soluble TM (rTM) has been used for treatment of individuals with DIC since 2008 in Japan, and a phase III clinical trial evaluating the efficacy of rTM in severe sepsis patients with coagulopathy is now ongoing in the USA, South America, Asia, Australia, European Union, and other countries. This review article discusses the molecular mechanisms by which the TM/APC system produces anticoagulant as well as anti-inflammatory and cytoprotective activities in septic DIC patients.

  5. Overview of the coagulation system

    PubMed Central

    Palta, Sanjeev; Saroa, Richa; Palta, Anshu

    2014-01-01

    Coagulation is a dynamic process and the understanding of the blood coagulation system has evolved over the recent years in anaesthetic practice. Although the traditional classification of the coagulation system into extrinsic and intrinsic pathway is still valid, the newer insights into coagulation provide more authentic description of the same. Normal coagulation pathway represents a balance between the pro coagulant pathway that is responsible for clot formation and the mechanisms that inhibit the same beyond the injury site. Imbalance of the coagulation system may occur in the perioperative period or during critical illness, which may be secondary to numerous factors leading to a tendency of either thrombosis or bleeding. A systematic search of literature on PubMed with MeSH terms ‘coagulation system, haemostasis and anaesthesia revealed twenty eight related clinical trials and review articles in last 10 years. Since the balance of the coagulation system may tilt towards bleeding and thrombosis in many situations, it is mandatory for the clinicians to understand physiologic basis of haemostasis in order to diagnose and manage the abnormalities of the coagulation process and to interpret the diagnostic tests done for the same. PMID:25535411

  6. Monocyte tissue factor–dependent activation of coagulation in hypercholesterolemic mice and monkeys is inhibited by simvastatin

    PubMed Central

    Owens, A. Phillip; Passam, Freda H.; Antoniak, Silvio; Marshall, Stephanie M.; McDaniel, Allison L.; Rudel, Lawrence; Williams, Julie C.; Hubbard, Brian K.; Dutton, Julie-Ann; Wang, Jianguo; Tobias, Peter S.; Curtiss, Linda K.; Daugherty, Alan; Kirchhofer, Daniel; Luyendyk, James P.; Moriarty, Patrick M.; Nagarajan, Shanmugam; Furie, Barbara C.; Furie, Bruce; Johns, Douglas G.; Temel, Ryan E.; Mackman, Nigel

    2012-01-01

    Hypercholesterolemia is a major risk factor for atherosclerosis. It also is associated with platelet hyperactivity, which increases morbidity and mortality from cardiovascular disease. However, the mechanisms by which hypercholesterolemia produces a procoagulant state remain undefined. Atherosclerosis is associated with accumulation of oxidized lipoproteins within atherosclerotic lesions. Small quantities of oxidized lipoproteins are also present in the circulation of patients with coronary artery disease. We therefore hypothesized that hypercholesterolemia leads to elevated levels of oxidized LDL (oxLDL) in plasma and that this induces expression of the procoagulant protein tissue factor (TF) in monocytes. In support of this hypothesis, we report here that oxLDL induced TF expression in human monocytic cells and monocytes. In addition, patients with familial hypercholesterolemia had elevated levels of plasma microparticle (MP) TF activity. Furthermore, a high-fat diet induced a time-dependent increase in plasma MP TF activity and activation of coagulation in both LDL receptor–deficient mice and African green monkeys. Genetic deficiency of TF in bone marrow cells reduced coagulation in hypercholesterolemic mice, consistent with a major role for monocyte-derived TF in the activation of coagulation. Similarly, a deficiency of either TLR4 or TLR6 reduced levels of MP TF activity. Simvastatin treatment of hypercholesterolemic mice and monkeys reduced oxLDL, monocyte TF expression, MP TF activity, activation of coagulation, and inflammation, without affecting total cholesterol levels. Our results suggest that the prothrombotic state associated with hypercholesterolemia is caused by oxLDL-mediated induction of TF expression in monocytes via engagement of a TLR4/TLR6 complex. PMID:22214850

  7. Blood clotting activation analysis for preoperative differentiation of benign versus malignant ovarian masses.

    PubMed

    Amirkhosravi, Ali; Bigsby, Glenn; Desai, Hina; Rivera-Amaya, Mildred; Coll, Enriqueta; Robles-Carrillo, Liza; Faust, Patricia; Waters, Alane; Meyer, Todd; Reyes, Enriquo; Langer, Florian; Francis, John L

    2013-07-01

    Preoperative evaluation of patients presenting with ovarian masses is challenging, partly due to shortcomings with the commonly used marker, CA-125. Ovarian cancer is associated with systemic coagulation activation. Measurement of D-dimer, serum tissue factor (TF), and the coagulation process as a whole are considered candidates for improving discrimination between benign and malignant ovarian masses. We therefore sought to identify possible benefits by analyzing preoperative coagulation status in conjunction with CA-125 in patients with ovarian masses. Preoperative blood from 95 patients with ovarian masses (75 benign, 20 malignant) and 30 controls was analyzed, prospectively. Thromboelastography served for global hemostatic assessment. Plasma TF antigen and D-dimer were measured by ELISA and microparticle-associated TF activity by thrombin generation assay. TF microparticles were enumerated by flow cytometry. Time to clot formation by thromboelastography was similar between patients having either benign or malignant ovarian tumors. Clot formation rate, clot strength, and coagulation index were significantly increased in patients having malignant versus benign tumors, indicating that thromboelastography differentiated malignant from benign tumors. D-dimer alone differentiated malignant from benign ovarian tumors and also improved differentiation when combined with CA-125. Circulating TF antigen, activity, and TF microparticle numbers, however, failed to differentiate benign from malignant tumors. Significant coagulation activation occurs in women with ovarian malignancies. Plasma D-dimer may help discriminate between patients with benign and malignant tumors. Thromboelastography may also contribute meaningfully when combined with CA-125 in the preoperative evaluation of ovarian masses. Larger studies are needed to assess these possibilities.

  8. The absorbed dose to blood from blood-borne activity

    NASA Astrophysics Data System (ADS)

    Hänscheid, H.; Fernández, M.; Lassmann, M.

    2015-01-01

    The radiation absorbed dose to blood and organs from activity in the blood is relevant for nuclear medicine dosimetry and for research in biodosimetry. The present study provides coefficients for the average absorbed dose rates to the blood from blood-borne activity for radionuclides frequently used in targeted radiotherapy and in PET diagnostics. The results were deduced from published data for vessel radius-dependent dose rate coefficients and reasonable assumptions on the blood-volume distribution as a function of the vessel radius. Different parts of the circulatory system were analyzed separately. Vessel size information for heart chambers, aorta, vena cava, pulmonary artery, and capillaries was taken from published results of morphometric measurements. The remaining blood not contained in the mentioned vessels was assumed to reside in fractal-like vascular trees, the smallest branches of which are the arterioles or venules. The applied vessel size distribution is consistent with recommendations of the ICRP on the blood-volume distribution in the human. The resulting average absorbed dose rates to the blood per nuclear disintegration per milliliter (ml) of blood are (in 10-11 Gy·s-1·Bq-1·ml) Y-90: 5.58, I-131: 2.49, Lu-177: 1.72, Sm-153: 2.97, Tc-99m: 0.366, C-11: 4.56, F-18: 3.61, Ga-68: 5.94, I-124: 2.55. Photon radiation contributes 1.1-1.2·10-11 Gy·s-1·Bq-1·ml to the total dose rate for positron emitters but significantly less for the other nuclides. Blood self-absorption of the energy emitted by ß-particles in the whole blood ranges from 37% for Y-90 to 80% for Tc-99m. The correspondent values in vascular trees, which are important for the absorbed dose to organs, range from 30% for Y-90 to 82% for Tc-99m.

  9. Rate of mixing controls rate and outcome of autocatalytic processes: theory and microfluidic experiments with chemical reactions and blood coagulation.

    PubMed

    Pompano, Rebecca R; Li, Hung-Wing; Ismagilov, Rustem F

    2008-08-01

    This article demonstrates that the rate of mixing can regulate the rate and outcome of both biological and nonbiological autocatalytic reaction systems that display a threshold response to the concentration of an activator. Plug-based microfluidics was used to control the timing of reactions, the rate of mixing, and surface chemistry in blood clotting and its chemical model. Initiation of clotting of human blood plasma required addition of a critical concentration of thrombin. Clotting could be prevented by rapid mixing when thrombin was added near the critical concentration, and mixing also affected the rate of clotting when thrombin was added at concentrations far above the critical concentration in two clinical clotting assays for human plasma. This phenomenon was modeled by a simple mechanism--local and global competition between the clotting reaction, which autocatalytically produces an activator, and mixing, which removes the activator. Numerical simulations showed that the Damköhler number, which describes this competition, predicts the effects of mixing. Many biological systems are controlled by thresholds, and these results shed light on the dynamics of these systems in the presence of spatial heterogeneities and provide simple guidelines for designing and interpreting experiments with such systems.

  10. Monitoring the effects of fibrinogen concentration on blood coagulation using quartz crystal microbalance (QCM) and its comparison with thromboelastography

    NASA Astrophysics Data System (ADS)

    Lakshmanan, Ramji S.; Efremov, Vitaly; Cullen, Sinéad; Byrne, Barry; Killard, Anthony J.

    2013-05-01

    Fibrinogen has been identified as a major risk factor in cardiovascular disorders. Fibrinogen (340 kDa) is a soluble dimeric glycoprotein found in plasma and is a major component of the coagulation cascade. It has been identified as a major risk factor in cardiovascular disorders. The time taken for its conversion to fibrin is usually used as an "endpoint" in most clot-based assays, without any information on dynamic changes in physical properties or kinetics of a forming clot. A global coagulation profile as measured by Thromboelastography® (TEG®) provides information on both the time and kinetics of changes in physical property of the forming clot. In this work, Quartz crystal microbalance (QCM), which is a piezoelectric resonator has been used to study coagulation of plasma and compared with TEG. The changes in resonant frequency (Δf) and half width at half maximum (HWHM or ΔΓ) were used to evaluate effect of fibrinogen concentration. It has been shown that TEG is less sensitive to low concentrations of fibrinogen and dilution while QCM is able to monitor clot formation in both the circumstances.

  11. Ovarian cancer, the coagulation pathway, and inflammation

    PubMed Central

    Wang, Xipeng; Wang, Ena; Kavanagh, John J; Freedman, Ralph S

    2005-01-01

    Epithelial ovarian cancer (EOC) represents the most frequent cause of death in the United States from a cancer involving the female genital tract. Contributing to the overall poor outcome in EOC patients, are the metastases to the peritoneum and stroma that are common in this cancer. In one study, cDNA microarray analysis was performed on fresh tissue to profile gene expression in patients with EOC. This study showed a number of genes with significantly altered expression in the pelvic peritoneum and stroma, and in the vicinity of EOC implants. These genes included those encoding coagulation factors and regulatory proteins in the coagulation cascade and genes encoding proteins associated with inflammatory responses. In addition to promoting the formation of blood clots, coagulation factors exhibit many other biologic functions as well as tumorigenic functions, the later including tumor cell proliferation, angiogenesis, invasion, and metastasis. Coagulation pathway proteins involved in tumorigenesis consist of factor II (thrombin), thrombin receptor (protease-activated receptors), factor III (tissue factor), factor VII, factor X and factor I (fibrinogen), and fibrin and factor XIII. In a recent study we conducted, we found that factor XII, factor XI, and several coagulation regulatory proteins, including heparin cofactor-II and epithelial protein C receptor (EPCR), were also upregulated in the peritoneum of EOC. In this review, we summarize evidence in support of a role for these factors in promoting tumor cell progression and the formation of ascites. We also discuss the different roles of coagulation factor pathways in the tumor and peritumoral microenvironments as they relate to angiogenesis, proliferation, invasion, and metastasis. . Since inflammatory responses are another characteristic of the peritoneum in EOC, we also discuss the linkage between the coagulation cascade and the cytokines/chemokines involved in inflammation. Interleukin-8, which is considered

  12. Ovarian cancer, the coagulation pathway, and inflammation.

    PubMed

    Wang, Xipeng; Wang, Ena; Kavanagh, John J; Freedman, Ralph S

    2005-06-21

    Epithelial ovarian cancer (EOC) represents the most frequent cause of death in the United States from a cancer involving the female genital tract. Contributing to the overall poor outcome in EOC patients, are the metastases to the peritoneum and stroma that are common in this cancer. In one study, cDNA microarray analysis was performed on fresh tissue to profile gene expression in patients with EOC. This study showed a number of genes with significantly altered expression in the pelvic peritoneum and stroma, and in the vicinity of EOC implants. These genes included those encoding coagulation factors and regulatory proteins in the coagulation cascade and genes encoding proteins associated with inflammatory responses. In addition to promoting the formation of blood clots, coagulation factors exhibit many other biologic functions as well as tumorigenic functions, the later including tumor cell proliferation, angiogenesis, invasion, and metastasis. Coagulation pathway proteins involved in tumorigenesis consist of factor II (thrombin), thrombin receptor (protease-activated receptors), factor III (tissue factor), factor VII, factor X and factor I (fibrinogen), and fibrin and factor XIII. In a recent study we conducted, we found that factor XII, factor XI, and several coagulation regulatory proteins, including heparin cofactor-II and epithelial protein C receptor (EPCR), were also upregulated in the peritoneum of EOC. In this review, we summarize evidence in support of a role for these factors in promoting tumor cell progression and the formation of ascites. We also discuss the different roles of coagulation factor pathways in the tumor and peritumoral microenvironments as they relate to angiogenesis, proliferation, invasion, and metastasis. Since inflammatory responses are another characteristic of the peritoneum in EOC, we also discuss the linkage between the coagulation cascade and the cytokines/chemokines involved in inflammation. Interleukin-8, which is considered an

  13. Do Biomarkers of Inflammation, Monocyte Activation, and Altered Coagulation Explain Excess Mortality Between HIV Infected and Uninfected People?

    PubMed Central

    Tate, Janet P.; Chang, Chung-Chou H.; Butt, Adeel A.; Gerschenson, Mariana; Gibert, Cynthia L.; Leaf, David; Rimland, David; Rodriguez-Barradas, Maria C.; Budoff, Matthew J.; Samet, Jeffrey H.; Kuller, Lewis H.; Deeks, Steven G.; Crothers, Kristina; Tracy, Russell P.; Crane, Heidi M.; Sajadi, Mohammad M.; Tindle, Hilary A.; Justice, Amy C.; Freiberg, Matthew S.

    2016-01-01

    Background: HIV infection and biomarkers of inflammation [measured by interleukin-6 (IL-6)], monocyte activation [soluble CD14 (sCD14)], and coagulation (D-dimer) are associated with morbidity and mortality. We hypothesized that these immunologic processes mediate (explain) some of the excess risk of mortality among HIV infected (HIV+) versus uninfected people independently of comorbid diseases. Methods: Among 2350 (1521 HIV+) participants from the Veterans Aging Cohort Study Biomarker Cohort (VACS BC), we investigated whether the association between HIV and mortality was altered by adjustment for IL-6, sCD14, and D-dimer, accounting for confounders. Participants were followed from date of blood draw for biomarker assays (baseline) until death or July 25, 2013. Analyses included ordered logistic regression and Cox Proportional Hazards regression. Results: During 6.9 years (median), 414 deaths occurred. The proportional odds of being in a higher quartile of IL-6, sCD14, or D-dimer were 2–3 fold higher for viremic HIV+ versus uninfected people. Mortality rates were higher among HIV+ compared with uninfected people [incidence rate ratio (95% CI): 1.31 (1.06 to 1.62)]. Mortality risk increased with increasing quartiles of IL-6, sCD14, and D-dimer regardless of HIV status. Adjustment for IL-6, sCD14, and D-dimer partially attenuated mortality risk among HIV+ people with unsuppressed viremia (HIV-1 RNA ≥10,000 copies per milliliter) compared with uninfected people—hazard ratio (95% CI) decreased from 2.18 (1.60 to 2.99) to 2.00 (1.45 to 2.76). Conclusions: HIV infection is associated with elevated IL-6, sCD14, and D-dimer, which are in turn associated with mortality. Baseline measures of these biomarkers partially mediate excess mortality risk among HIV+ versus uninfected people. PMID:26885807

  14. Disseminated intravascular coagulation in sepsis.

    PubMed

    Zeerleder, Sacha; Hack, C Erik; Wuillemin, Walter A

    2005-10-01

    Disseminated intravascular coagulation is a frequent complication of sepsis. Coagulation activation, inhibition of fibrinolysis, and consumption of coagulation inhibitors lead to a procoagulant state resulting in inadequate fibrin removal and fibrin deposition in the microvasculature. As a consequence, microvascular thrombosis contributes to promotion of organ dysfunction. Recently, three randomized, double-blind, placebo-controlled trials investigated the efficacy of antithrombin, activated protein C (APC), and tissue factor pathway inhibitor, respectively, in sepsis patients. A significant reduction in mortality was demonstrated in the APC trial. In this article, we first discuss the physiology of coagulation and fibrinolysis activation. Then, the pathophysiology of coagulation activation, consumption of coagulation inhibitors, and the inhibition of fibrinolysis leading to a procoagulant state are described in more detail. Moreover, therapeutic concepts as well as the three randomized, double-blind, placebo-controlled studies are discussed.

  15. Disseminated intravascular coagulation in burn injury.

    PubMed

    Lippi, Giuseppe; Ippolito, Luigi; Cervellin, Gianfranco

    2010-06-01

    Disseminated intravascular coagulation (DIC) is a complex and multifaceted disorder characterized by the activation of coagulation and fibrinolytic pathways, consumption of coagulation factors, and depletion of coagulation regulatory proteins. The introduction into the circulation of cellular debris characterized by strong thromboplastic activity due to tissue factor exposition or release (in or from burned tissues), which can thereby activate extrinsic pathway of coagulation system and trigger massive thrombin generation when present in sufficient concentration, represents the most plausible biological explanation to support the development of intravascular coagulation in patients with burn injury. Severe burns left untreated might also lead to an immunological and inflammatory response (activation of the complement cascade), which can amplify fibrinolysis and blood clotting. Overall, the real prevalence of DIC in patients with burns is as yet unclear. Postmortem, retrospective, and even longitudinal investigations are in fact biased by several factors, such as the objective difficulty to establish whether DIC might have occurred as a primary complication of burns or rather as a consequence of other superimposed pathologies (e.g., sepsis, multiple organ failure), the different diagnostic criteria for assessing DIC, and the heterogeneity of the patient samples studied. Nevertheless, the current scientific evidence is consistent with the hypothesis that biochemical changes suggestive for DIC (hypercoagulability, hypo- and hyperfibrinolysis) are commonplace in patients with burn trauma, and their severity increases exponentially with the severity of injury. Overt DIC seems to occur especially in critically ill burn patients or in those with severe burns (up to third degree) and large involvement of body surface area, in whom an appropriate therapy might be effective to prevent the otherwise fulminant course. Although early prophylaxis with antithrombin concentrates

  16. Monopolar active accessories can be connected to Covidien ForceTriad electrosurgical generators incorrectly, disabling coagulation mode.

    PubMed

    2011-03-01

    The monopolar output receptacle on the Covidien ForceTriad electrosurgical generator is designed in such a way that users can unknowingly connect active accessories in the wrong orientation, disabling the system's coagulation function. The manufacturer is developing labeling for ForceTriad production units that depicts the proper orientation in which to connect the accessory during setup. Covidien is currently considering how it will address units already in the field.

  17. High Pressure Homogenization of Porcine Pepsin Protease: Effects on Enzyme Activity, Stability, Milk Coagulation Profile and Gel Development.

    PubMed

    Leite Júnior, Bruno Ricardo de Castro; Tribst, Alline Artigiani Lima; Cristianini, Marcelo

    2015-01-01

    This study investigated the effect of high pressure homogenization (HPH) (up to 190 MPa) on porcine pepsin (proteolytic and milk-clotting activities), and the consequences of using the processed enzyme in milk coagulation and gel formation (rheological profile, proteolysis, syneresis, and microstructure). Although the proteolytic activity (PA) was not altered immediately after the HPH process, it reduced during enzyme storage, with a 5% decrease after 60 days of storage for samples obtained with the enzyme processed at 50, 100 and 150 MPa. HPH increased the milk-clotting activity (MCA) of the enzyme processed at 150 MPa, being 15% higher than the MCA of non-processed samples after 60 days of storage. The enzyme processed at 150 MPa produced faster aggregation and a more consistent milk gel (G' value 92% higher after 90 minutes) when compared with the non-processed enzyme. In addition, the gels produced with the enzyme processed at 150 MPa showed greater syneresis after 40 minutes of coagulation (forming a more compact protein network) and lower porosity (evidenced by confocal microscopy). These effects on the milk gel can be associated with the increment in MCA and reduction in PA caused by the effects of HPH on pepsin during storage. According to the results, HPH stands out as a process capable of changing the proteolytic characteristics of porcine pepsin, with improvements on the milk coagulation step and gel characteristics. Therefore, the porcine pepsin submitted to HPH process can be a suitable alternative for the production of cheese.

  18. High Pressure Homogenization of Porcine Pepsin Protease: Effects on Enzyme Activity, Stability, Milk Coagulation Profile and Gel Development

    PubMed Central

    Leite Júnior, Bruno Ricardo de Castro; Tribst, Alline Artigiani Lima; Cristianini, Marcelo

    2015-01-01

    This study investigated the effect of high pressure homogenization (HPH) (up to 190 MPa) on porcine pepsin (proteolytic and milk-clotting activities), and the consequences of using the processed enzyme in milk coagulation and gel formation (rheological profile, proteolysis, syneresis, and microstructure). Although the proteolytic activity (PA) was not altered immediately after the HPH process, it reduced during enzyme storage, with a 5% decrease after 60 days of storage for samples obtained with the enzyme processed at 50, 100 and 150 MPa. HPH increased the milk-clotting activity (MCA) of the enzyme processed at 150 MPa, being 15% higher than the MCA of non-processed samples after 60 days of storage. The enzyme processed at 150 MPa produced faster aggregation and a more consistent milk gel (G’ value 92% higher after 90 minutes) when compared with the non-processed enzyme. In addition, the gels produced with the enzyme processed at 150 MPa showed greater syneresis after 40 minutes of coagulation (forming a more compact protein network) and lower porosity (evidenced by confocal microscopy). These effects on the milk gel can be associated with the increment in MCA and reduction in PA caused by the effects of HPH on pepsin during storage. According to the results, HPH stands out as a process capable of changing the proteolytic characteristics of porcine pepsin, with improvements on the milk coagulation step and gel characteristics. Therefore, the porcine pepsin submitted to HPH process can be a suitable alternative for the production of cheese. PMID:25938823

  19. The role of carrier number on the procoagulant activity of tissue factor in blood and plasma

    NASA Astrophysics Data System (ADS)

    Tormoen, G. W.; Rugonyi, S.; Gruber, A.; McCarty, O. J. T.

    2011-12-01

    Tissue factor (TF) is a transmembrane glycoprotein cofactor of activated blood coagulation factor VII (FVIIa) that is required for hemostatic thrombin generation at sites of blood vessel injury. Membrane-associated TF detected in circulating blood of healthy subjects, referred to as intravascular or circulating TF has been shown to contribute to experimental thrombus propagation at sites of localized vessel injury. Certain disease states, such as metastatic cancer, are associated with increased levels of intravascular TF and an elevated risk of venous thromboembolism. However, the physiological relevance of circulating TF to hemostasis or thrombosis, as well as cancer metastasis, is ill-defined. This study was designed to assess whether the spatial separation of intravascular TF carriers in blood, demonstrated with TF-inducible human monocytic cell line U937 or TF-coated polymer microspheres, affected procoagulant activity and hence thrombogenic potential. Experiments were performed to characterize the effects of TF-carrier number on the kinetics of clot formation in both open and closed systems. The procoagulant activity of TF carriers was found to correlate with spatial separation in both closed, well-mixed systems and open, flowing systems. TF carriers enhanced the amidolytic activity of FVIIa toward the chromogenic substrate, S-2366, as a function of carrier count. These results suggest that TF-initiated coagulation by circulating TF is kinetically limited by mass transport of TF-dependent coagulation factors to the TF-bearing surface, a constraint that may be unique to circulating TF. Spatial separation of circulating TF carriers is therefore a critical determinant of the procoagulant activity of circulating TF.

  20. [Pitfall in coagulation tests].

    PubMed

    Gähler, Anita; Wuillemin, Walter A

    2013-08-01

    Coagulation assays are prone to pre-analytical problems and results may be influenced by varying clinical and pharmaceutical aspects. Particularly anticoagulants interact with coagulation testing in many ways. Thromboplastin time will be prolonged dose-dependently in patients taking vitamin K antagonists; moreover the new oral anticoagulants have been shown to have variable impact on the results of the thromboplastin time as well as on other coagulation tests, depending on the mechanism of action of these new drugs as well as on the mechanism of the coagulation test. When measuring anti-Xa activity it should be realised that all drugs with anti-Xa activity will influence the result, which means not only heparins but also the new anti-Xa inhibitors. Respective calibration curves are an indispensable condition to provide the clinician with valuable results. On the other hand this implies that the laboratory knows which anticoagulant is given to the patient. This is an example among others that clinical aspects are important to know for proper interpretation of the results of coagulation testing. Other examples are e. g. bleeding disorders, actual bleeding status or thromboembolic events. Several cases are discussed which exemplify possible pitfalls in the interpretation of coagulation testing.

  1. Chitotriosidase activity in goat blood and colostrum.

    PubMed

    Argüello, A; Castro, N; Batista, M; Moreno-Indias, I; Morales-delaNuez, A; Sanchez-Macias, D; Quesada, E; Capote, J

    2008-05-01

    Chitotriosidase (ChT) activity has not been investigated in ruminants, and therefore, we studied this activity in blood and colostrum of 25 pregnant goats and 60 goat kids. Blood samples were taken from pregnant goats at 3, 2, and 1 d prepartum; at partum; and at 1, 2, 3, and 4 d postpartum. Colostrum samples were obtained by machine-milking at partum and 1, 2, 3, and 4 d postpartum. Goat kid blood was collected at birth and every 7 d thereafter until goats kids were 56 d old. The ChT activity ranged from 2,368 to 3,350 nmol/ mL per hour in goat blood serum, and no statistical differences were detected through time. However, activity tended to decrease from 3 d prepartum to 2 d post-partum. Colostrum ChT activity was 3,912 nmol/mL per hour and 465 nmol/mL per hour on the day of delivery and 4 d postpartum, respectively. Colostrum ChT activity was significantly higher at partum than at any other time. The ChT activity in colostrum was significantly greater at 1 d postpartum than at 2, 3, and 4 d postpartum. Chitotriosidase activity did not differ in colostrum collected on d 2, 3, and 4 postpartum. Chitotriosidase activity in goat kid blood serum ranged from 2,664 to 9,231 nmol/mL per hour at birth and 49 d of life, respectively. Chitotriosidase activity in the blood serum increased with age: at birth, activity was significantly less than at 28, 35, 42, 49, and 56 d postpartum. The maximum ChT activity in blood serum was observed at 49 d postpartum. Activity in 49-d-old kids was significantly greater than that observed in kids at 0, 7, and 14 d postpartum.

  2. [Ratio of erythrocyte and plasma in massive blood transfusion].

    PubMed

    Wen, Xian-Hui; Liu, Feng-Xia; Zhang, Jun-Hua; Gui, Rong

    2014-06-01

    This study was purposed to explore the suitable ratio between fresh frozen plasma and erythrocyte by retrospective analysis of coagulation in patients with massive blood transfusion. The clinical data of 151 cases with massive blood transfusion from January 2011 to January 2013 were analyzed retrospectively. According to coagulation, patients were divided into coagulation normal group (138 cases) and coagulation dysfunction group (13 cases). Based on the ratio of 1:1 of fresh frozen plasma and erythrocyte, the patients were divided into high plasma group(2:1), medium plasma group (1:1) and low plasma (<1:1) subgroups. Coagulation was detected before and after 24 h of massive blood transfusion. The results showed that prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) were prolonged, fibrinogen (FIB) level decreased significantly (all P < 0.05) in the low plasma subgroup of coagulation normal group after massive blood transfusion 24 h; the high plasma and the medium plasma group of coagulation normal group had no significant changes in coagulation (P > 0.05); prothrombin time, activated partial thromboplastin time, thrombin time and fibrinogen level in the medium plasma and low plasma subgroup of coagulation dysfunction group after massive transfusion was still in abnormal levels (P > 0.05), coagulation function in high plasma subgroup was improved significantly (P < 0.05). It is concluded that the ratio of plasma to erythrocyte should be adjusted according to the patient's coagulation function during massive blood transfusion, the ratio between fresh frozen plasma and erythrocyte is recommended to be 2:1 in patients of coagulation dysfunction in order to improve the patient's coagulation function and to reduce the incidence of adverse event, the ratio of fresh frozen plasma to erythrocyte is recommended to be 1:1 in patients with normal coagulation so as to reduce the dilutional coagulopathy and hypervolemia of blood.

  3. Effects of unfractionated heparin, low-molecular-weight heparin, and heparinoid on thromboelastographic assay of blood coagulation.

    PubMed

    Zmuda, K; Neofotistos, D; Ts'ao, C H

    2000-05-01

    Thromboelastography (TEG) has been used increasingly as an intraoperative hemostasis monitoring device. Low-molecular-weight heparins are given increasingly to reduce the development of antibodies against the heparin-platelet factor 4 complex, and heparinoids are given to patients who have developed the antibody. We studied the effect of unfractionated heparin, a low-molecular-weight heparin (enoxaparin sodium [Lovenox]), and a heparinoid (danaparoid sodium [Orgaran]) on blood clotting assayed with TEG (TEG clotting) in vitro and the efficacy of protamine sulfate and heparinase for reversing the effect. Heparin, enoxaparin, and danaparoid all caused a dose-dependent inhibition of TEG clotting of normal blood. Concentrations of enoxaparin and danaparoid that totally inhibited TEG clotting only minimally prolonged the activated partial thromboplastin time. While inhibition of TEG clotting by heparin and enoxaparin was reversed by protamine sulfate and heparinase, inhibition by danaparoid was reversed only by heparinase. Abnormal TEG clotting was observed in patients receiving enoxaparin whose plasma level of the drug was more than 0.1 antiXa U/mL. However, the degree of TEG abnormality did not always coincide with plasma levels of the drug.

  4. Ribavirin-induced intracellular GTP depletion activates transcription elongation in coagulation factor VII gene expression.

    PubMed

    Suzuki, Atsuo; Miyawaki, Yuhri; Okuyama, Eriko; Murata, Moe; Ando, Yumi; Kato, Io; Takagi, Yuki; Takagi, Akira; Murate, Takashi; Saito, Hidehiko; Kojima, Tetsuhito

    2013-01-01

    Coagulation FVII (Factor VII) is a vitamin K-dependent glycoprotein synthesized in hepatocytes. It was reported previously that FVII gene (F7) expression was up-regulated by ribavirin treatment in hepatitis C virus-infected haemophilia patients; however, its precise mechanism is still unknown. In the present study, we investigated the molecular mechanism of ribavirin-induced up-regulation of F7 expression in HepG2 (human hepatoma cell line). We found that intracellular GTP depletion by ribavirin as well as other IMPDH (inosine-5'-monophosphate dehydrogenase) inhibitors, such as mycophenolic acid and 6-mercaptopurine, up-regulated F7 expression. FVII mRNA transcription was mainly enhanced by accelerated transcription elongation, which was mediated by the P-TEFb (positive-transcription elongation factor b) complex, rather than by promoter activation. Ribavirin unregulated ELL (eleven-nineteen lysine-rich leukaemia) 3 mRNA expression before F7 up-regulation. We observed that ribavirin enhanced ELL3 recruitment to F7, whereas knockdown of ELL3 diminished ribavirin-induced FVII mRNA up-regulation. Ribavirin also enhanced recruitment of CDK9 (cyclin-dependent kinase 9) and AFF4 to F7. These data suggest that ribavirin-induced intracellular GTP depletion recruits a super elongation complex containing P-TEFb, AFF4 and ELL3, to F7, and modulates FVII mRNA transcription elongation. Collectively, we have elucidated a basal mechanism for ribavirin-induced FVII mRNA up-regulation by acceleration of transcription elongation, which may be crucial in understanding its pleiotropic functions in vivo.

  5. Platelet-Derived Short-Chain Polyphosphates Enhance the Inactivation of Tissue Factor Pathway Inhibitor by Activated Coagulation Factor XI

    PubMed Central

    Puy, Cristina; Tucker, Erik I.; Ivanov, Ivan S.; Gailani, David; Smith, Stephanie A.; Morrissey, James H.; Gruber, András; McCarty, Owen J. T.

    2016-01-01

    Introduction Factor (F) XI supports both normal human hemostasis and pathological thrombosis. Activated FXI (FXIa) promotes thrombin generation by enzymatic activation of FXI, FIX, FX, and FV, and inactivation of alpha tissue factor pathway inhibitor (TFPIα), in vitro. Some of these reactions are now known to be enhanced by short-chain polyphosphates (SCP) derived from activated platelets. These SCPs act as a cofactor for the activation of FXI and FV by thrombin and FXIa, respectively. Since SCPs have been shown to inhibit the anticoagulant function of TFPIα, we herein investigated whether SCPs could serve as cofactors for the proteolytic inactivation of TFPIα by FXIa, further promoting the efficiency of the extrinsic pathway of coagulation to generate thrombin. Methods and Results Purified soluble SCP was prepared by size-fractionation of sodium polyphosphate. TFPIα proteolysis was analyzed by western blot. TFPIα activity was measured as inhibition of FX activation and activity in coagulation and chromogenic assays. SCPs significantly accelerated the rate of inactivation of TFPIα by FXIa in both purified systems and in recalcified plasma. Moreover, platelet-derived SCP accelerated the rate of inactivation of platelet-derived TFPIα by FXIa. TFPIα activity was not affected by SCP in recalcified FXI-depleted plasma. Conclusions Our data suggest that SCP is a cofactor for TFPIα inactivation by FXIa, thus, expanding the range of hemostatic FXIa substrates that may be affected by the cofactor functions of platelet-derived SCP. PMID:27764259

  6. Activation patterns of coagulation and fibrinolysis in baboons following infusion with lethal or sublethal dose of Escherichia coli.

    PubMed

    de Boer, J P; Creasy, A A; Chang, A; Roem, D; Brouwer, M C; Eerenberg, A J; Hack, C E; Taylor, F B

    1993-01-01

    Administration of low doses endotoxin or tumor necrosis factor (TNF) in human experimental models for sepsis results in transient activation of both coagulation and fibrinolysis and subsequent inhibition of the fibrinolytic system by plasminogen activator inhibitor type 1 (PAI-1). We have investigated in a baboon model for sepsis, whether administration of a lethal or sublethal dose of living E. coli could induce similar activation patterns. Levels of thrombin-antithrombin III (TAT) complexes increased significantly to zeniths of 425 and 33 times the baseline values at t+360 in the lethal and sublethal group, respectively. Activation of fibrinolysis, as reflected by plasmin-alpha 2 antiplasmin (PAP) complexes, in the sublethal group was maximal at t+60 and was increasingly inhibited thereafter in spite of a sustained increase of tissue type plasminogen activator (t-PA) levels. In the lethal group PAP complexes increased to a zenith of 38 times the baseline values at t+240. PAI-1 levels increased to 15 times the baseline values at t+360 in the sublethal group, whereas in the lethal group they increased almost linearly to 20 times the baseline values at t+360. Despite high levels of PAI-1, effective inhibition of the fibrinolysis was not established until at T+240 in the lethal group. The difference in activation patterns of both mediator systems in the sublethal and lethal group of baboons indicate that extensive activation of coagulation contributes to the lethal complications in sepsis.

  7. Transfusion and coagulation management in liver transplantation

    PubMed Central

    Clevenger, Ben; Mallett, Susan V

    2014-01-01

    There is wide variation in the management of coagulation and blood transfusion practice in liver transplantation. The use of blood products intraoperatively is declining and transfusion free transplantations take place ever more frequently. Allogenic blood products have been shown to increase morbidity and mortality. Primary haemostasis, coagulation and fibrinolysis are altered by liver disease. This, combined with intraoperative disturbances of coagulation, increases the risk of bleeding. Meanwhile, the rebalancing of coagulation homeostasis can put patients at risk of hypercoagulability and thrombosis. The application of the principles of patient blood management to transplantation can reduce the risk of transfusion. This includes: preoperative recognition and treatment of anaemia, reduction of perioperative blood loss and the use of restrictive haemoglobin based transfusion triggers. The use of point of care coagulation monitoring using whole blood viscoelastic testing provides a picture of the complete coagulation process by which to guide and direct coagulation management. Pharmacological methods to reduce blood loss include the use of anti-fibrinolytic drugs to reduce fibrinolysis, and rarely, the use of recombinant factor VIIa. Factor concentrates are increasingly used; fibrinogen concentrates to improve clot strength and stability, and prothrombin complex concentrates to improve thrombin generation. Non-pharmacological methods to reduce blood loss include surgical utilisation of the piggyback technique and maintenance of a low central venous pressure. The use of intraoperative cell salvage and normovolaemic haemodilution reduces allogenic blood transfusion. Further research into methods of decreasing blood loss and alternatives to blood transfusion remains necessary to continue to improve outcomes after transplantation. PMID:24876736

  8. Keeping the blood flowing-plasminogen activator genes and feeding behavior in vampire bats.

    PubMed

    Tellgren-Roth, Asa; Dittmar, Katharina; Massey, Steven E; Kemi, Cecilia; Tellgren-Roth, Christian; Savolainen, Peter; Lyons, Leslie A; Liberles, David A

    2009-01-01

    The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator, a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species. Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding behavior among vampire bat species from bird to mammalian blood.

  9. Keeping the blood flowing—plasminogen activator genes and feeding behavior in vampire bats

    NASA Astrophysics Data System (ADS)

    Tellgren-Roth, Åsa; Dittmar, Katharina; Massey, Steven E.; Kemi, Cecilia; Tellgren-Roth, Christian; Savolainen, Peter; Lyons, Leslie A.; Liberles, David A.

    2009-01-01

    The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator, a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species. Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding behavior among vampire bat species from bird to mammalian blood.

  10. Activation of coagulation and fibrinolysis following OKT3 administration to renal transplant recipients: association with distinct mediators.

    PubMed

    Raasveld, M H; Hack, C E; ten Berge, I J

    1992-09-01

    Treatment with OKT3 induces cytokine release and activates the complement system. Since both phenomena may affect coagulation and fibrinolysis we studied these systems in 8 renal transplant recipients during OKT3 treatment. In 8 of 9 patients a similar pattern was observed: plasma thrombin-antithrombin-III-complex, tissue-type plasminogen-activator and plasmin-alpha 2-antiplasmin-complex levels were increased as compared to pretreatment levels (p less than 0.05) at 15 min after the first OKT3 dose and reached peak values at 1 h. No significant changes were observed upon subsequent OKT3 administrations or in a control group of 8 patients. In one patient upon the first OKT3 administration only complement activation, and no cytokine release was observed, whereas plasma thrombin-antithrombin-III-complex, tissue-type plasminogen-activator and plasmin-alpha 2-antiplasmin-complex levels increased only at 15 min. In conclusion, we demonstrate a biphasic activation of coagulation and fibrinolysis upon the first OKT3 dose; the initial phase seems to be associated with complement activation, the later phase with cytokine release.

  11. [Coagulation disorders in the intensive care station].

    PubMed

    Hart, C; Spannagl, M

    2014-05-01

    Coagulation disorders are frequently encountered in the intensive care unit (ICU) and are challenging due to a variety of potential etiologies. Critically ill patients with coagulation abnormalities may present with an increased risk of bleeding, show coagulation activation resulting in thromboembolism, or have no specific symptoms. Hemostatic abnormalities observed in ICU patients range from isolated thrombocytopenia or prolonged global clotting tests to complex and life-threatening coagulation defects. Successful management of coagulation disorders requires prompt and accurate identification of the underlying cause. This review describes the most frequently occurring diagnoses found in intensive care patients with thrombocytopenia and coagulation test abnormalities and summarizes appropriate diagnostic interventions and current approaches to differential diagnosis.

  12. Hysteresis-like binding of coagulation factors X/Xa to procoagulant activated platelets and phospholipids results from multistep association and membrane-dependent multimerization.

    PubMed

    Podoplelova, Nadezhda A; Sveshnikova, Anastasia N; Kurasawa, James H; Sarafanov, Andrey G; Chambost, Herve; Vasil'ev, Sergey A; Demina, Irina A; Ataullakhanov, Fazly I; Alessi, Marie-Christine; Panteleev, Mikhail A

    2016-06-01

    Binding of coagulation factors X (fX) and Xa (fXa) to activated platelets is required for the formation of membrane-dependent enzymatic complexes of intrinsic tenase and prothrombinase. We carried out an in-depth characterization of fX/fXa binding to phospholipids and gel-filtered, thrombin-activated platelets. Flow cytometry, surface plasmon resonance, and computational modeling were used to investigate interactions of fX/fXa with the membranes. Confocal microscopy was employed to study fXa binding to platelet thrombi formed in flowing whole blood under arterial conditions. Binding of fX/fXa to either vesicles or procoagulant platelets did not follow a traditional one-step reversible binding model. Their dissociation was a two-step process resulting in a plateau that was up to 10-fold greater than the saturation value observed in the association experiments. Computational modeling and experimental evidence suggested that this was caused by a combination of two-step association (mainly for fX) and multimerization on the membrane (mainly for fXa). Importantly, fX formed multimers with fXa, thereby improving its retention. The same binding/dissociation hysteresis was observed for annexin V known to form trimers on the membranes. Experiments with platelets from gray syndrome patients showed that alpha-granular factor Va provided an additional high-affinity binding site for fXa that did not affect the hysteresis. Confocal microscopy observation of fXa binding to platelet thrombi in a flow chamber and its wash-out confirmed that this phenomenon persisted under physiologically relevant conditions. This suggests its possible role of "locking" coagulation factors on the membrane and preventing their inhibition in plasma and removal from thrombi by flow.

  13. A comparative study of coagulation, granular- and powdered-activated carbon for the removal of perfluorooctane sulfonate and perfluorooctanoate in drinking water treatment.

    PubMed

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Suja, Fatihah

    2015-01-01

    Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are persistent organic pollutants in the environment and their occurrence causes toxicological effects on humans. We examined different conventional coagulant treatments such as alum, ferric chloride and polyaluminium chloride in removing these compounds. These were then compared with a natural coagulant (Moringa oleifera). We also investigated the powdered-activated carbon (PAC) and granular-activated carbon (GAC) for removing these compounds. At an initial dose of 5 mg/L, polyaluminium chloride led to a higher reduction of PFOS/PFOA compared with alum which in turn was higher than ferric. The removal efficiency increased with the increase in coagulant dose and decrease in pH. M. oleifera was very effective in reducing PFOS and PFOA than conventional coagulants, with a reduction efficiencies of 65% and 72%, respectively, at a dose of 30 mg/L. Both PAC and GAC were very effective in reducing these compounds than coagulations. PAC led to a higher reduction in PFOS and PFOA than GAC due to its greater surface area and shorter internal diffusion distances. The addition of PAC (10 min contact time) with coagulation (at 5 mg/L dosage) significantly increased the removal efficiency, and the maximum removal efficiency was for M. oleifera with 98% and 94% for PFOS and PFOA, respectively. The reduction efficiency of PFOS/PFOA was reduced with the increase in dissolved organic concentration due to the adsorption competition between organic molecules and PFOS/PFOA. PMID:25860623

  14. A comparative study of coagulation, granular- and powdered-activated carbon for the removal of perfluorooctane sulfonate and perfluorooctanoate in drinking water treatment.

    PubMed

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Suja, Fatihah

    2015-01-01

    Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are persistent organic pollutants in the environment and their occurrence causes toxicological effects on humans. We examined different conventional coagulant treatments such as alum, ferric chloride and polyaluminium chloride in removing these compounds. These were then compared with a natural coagulant (Moringa oleifera). We also investigated the powdered-activated carbon (PAC) and granular-activated carbon (GAC) for removing these compounds. At an initial dose of 5 mg/L, polyaluminium chloride led to a higher reduction of PFOS/PFOA compared with alum which in turn was higher than ferric. The removal efficiency increased with the increase in coagulant dose and decrease in pH. M. oleifera was very effective in reducing PFOS and PFOA than conventional coagulants, with a reduction efficiencies of 65% and 72%, respectively, at a dose of 30 mg/L. Both PAC and GAC were very effective in reducing these compounds than coagulations. PAC led to a higher reduction in PFOS and PFOA than GAC due to its greater surface area and shorter internal diffusion distances. The addition of PAC (10 min contact time) with coagulation (at 5 mg/L dosage) significantly increased the removal efficiency, and the maximum removal efficiency was for M. oleifera with 98% and 94% for PFOS and PFOA, respectively. The reduction efficiency of PFOS/PFOA was reduced with the increase in dissolved organic concentration due to the adsorption competition between organic molecules and PFOS/PFOA.

  15. Determination of tumor cell procoagulant activity by Sonoclot analysis in whole blood.

    PubMed

    Amirkhosravi, A; Biggerstaff, J P; Warnes, G; Francis, D A; Francis, J L

    1996-12-01

    Coagulation activation in cancer may be due to expression of procoagulant activity (PCA) by tumor cells. Some PCA activate coagulation, while others influence platelet aggregation. Thus, clotting time assessments of PCA may not reflect the potential for hypercoagulability. We therefore studied the effect of various malignant and non-malignant cells on whole blood coagulation using the Sonoclot Analyzer. Five human (HT29 colon, J82 bladder, MCF-7 breast, BT-474 breast and A375 malignant melanoma) and three rodent (MC28, WEHI-164 and Neuro2a) cell lines were used. Rat thymocytes and peritoneal macrophages and human endotoxin-stimulated mononuclear cells and umbilical vein endothelial cells (HUVEC) were used as non-malignant controls. All tumor cells markedly shortened the recalcification time of citrated blood and the most potent (HT29 and J82) also increased clot rate (P < 0.01). The breast cancer cells MCF-7 and BT-474 expressed only weak PCA and did not affect clotting rate. None of the non-malignant cells significantly affected clotting time or rate in whole blood. J82 and HT29 cells grown in serum-rich media shortened the recalcification time of both normal and FVII-deficient plasmas. However, cells grown in serum-free conditions had significantly less PCA in FVII-deficient plasma. We conclude that the Sonoclot Analyzer is useful for determining cellular PCA; significant PCA is a feature of malignant cells and cells grown in medium containing serum supplements cannot be reliably evaluated for PCA. PMID:8948059

  16. Interpreting coagulation assays.

    PubMed

    Green, David

    2010-09-01

    The interpretation of coagulation assays requires knowledge of the principal clotting pathways. The activated partial thromboplastin time is sensitive to all hemostatic factors except FVII, whereas the prothrombin time reflects levels of prothrombin and FV, FVII, and FX. Using the two tests in concert is helpful in identifying hemophilia, the coagulopathy of liver disease, and disseminated intravascular coagulation. In addition, the activated partial thromboplastin time and prothrombin time are used for monitoring anticoagulant therapy with heparin and warfarin, respectively. Measurement of D-dimer is informative in patients suspected of having thrombotic disorders and determining the risk of thrombosis recurrence. Mixing tests distinguish clotting factor deficiencies from circulating anticoagulants such as heparin, the lupus anticoagulant, and antibodies directed against specific clotting factors. The modified Bethesda assay detects and provides an indication of the strength of FVIII inhibitors. However, interpreting the results of coagulation assays is not always straightforward, and expert consultation is occasionally required to resolve difficult clinical situations. PMID:20855988

  17. Endoscopic hemostasis by injection therapy and electro-hydro-coagulation in high-risk patients with active gastroduodenal bleeding ulcer.

    PubMed

    Boix, J; Planas, R; Humbert, P; Fabrega, C; Villagrasa, M

    1987-11-01

    For the purpose of arresting hemorrhage from bleeding gastric or duodenal ulcers we developed, in 28 high-risk patients, a new method of endoscopic local injection of epinephrine (1:10,000) followed by electro-hydro monopolar coagulation and injection of Polidocanol (1%). Nine patients had signs of shock at the time of admission. The average blood requirements were 3.9 units in the first 24 hours. All patients had important factors militating against surgery, namely age and serious primary disease. In 26 out of 28 patients (92.8%) hemostasis was accomplished during endoscopy. Three patients (10.7%) rebled within the first 36 hours, requiring emergency surgery. Thus definitive hemostasis was achieved in 23 patients (82.1%). There were no complications as a result of endoscopic treatment.

  18. A Mixture of Ethanol Extracts of Persimmon Leaf and Citrus junos Sieb Improves Blood Coagulation Parameters and Ameliorates Lipid Metabolism Disturbances Caused by Diet-Induced Obesity in C57BL/6J Mice.

    PubMed

    Kim, Ae Hyang; Kim, Hye Jin; Ryu, Ri; Han, Hye Jin; Han, Young Ji; Lee, Mi-Kyung; Choi, Myung-Sook; Park, Yong Bok

    2016-02-01

    This study investigated the effects of a flavonoid-rich ethanol extract of persimmon leaf (PL), an ethanol extract of Citrus junos Sieb (CJS), and a PL-CJS mixture (MPC) on mice fed a highfat diet (HFD). We sought to elucidate the mechanisms of biological activity of these substances using measurements of blood coagulation indices and lipid metabolism parameters. C57BL/6J mice were fed a HFD with PL (0.5% (w/w)), CJS (0.1% (w/w)), or MPC (PL 0.5%, CJS 0.1% (w/w)) for 10 weeks. In comparison with data obtained for mice in the untreated HFD group, consumption of MPC remarkably prolonged the activated partial thromboplastin time (aPTT) and prothrombin time (PT), whereas exposure to PL prolonged aPTT only. Lower levels of plasma total cholesterol, hepatic cholesterol, and erythrocyte thiobarbituric acid-reactive substances, hepatic HMG-CoA reductase, and decreased SREBP-1c gene expression were observed in mice that received PL and MPC supplements compared with the respective values detected in the untreated HFD animals. Our results indicate that PL and MPC may have beneficial effects on blood circulation and lipid metabolism in obese mice. PMID:26699754

  19. Peptide analogues of 1811-1818 loop of the A3 subunit of the light chain A3-C1-C2 of FVIII of blood coagulation: biological evaluation.

    PubMed

    Patsialas, K; Koutsas, C; Makris, P; Liakopoulou-Kyriakides, Maria

    2010-07-01

    Factor VIII, the plasma protein deficient or defective in individuals with hemophilia A, is a critical member of the blood coagulation cascade. Recent studies have identified the FVIII light chain region Glu1811-Lys1818 as being involved in FIXa binding and in the assembly of the FX-activating FIXaz-FVIIIa complex. Based on this, a series of 12 peptides, analogues of the 1811-1818 loop of the A3 subunit of the light chain A3-C1-C2 of FVIIIa, were synthesized and evaluated for their anticoagulant activity. Only peptide Ac-ETKTYFWK-NH(2) showed significant anticoagulant activity by inhibiting about 40% factor VIII at a concentration of 0.43 mM. It also showed a prolongation of activated partial thromboplastin time of 6.1 s, whereas its effect on prothrombin time measurements was meaningless. All the other peptides did not show any measurable effect at the concentration of 0.43 mM. These findings are encouraging though further investigation of the effect of this active peptide in different biological settings is needed in order to evaluate its possible clinical applications.

  20. Endovascular treatment of chronic cerebro spinal venous insufficiency in patients with multiple sclerosis modifies circulating markers of endothelial dysfunction and coagulation activation: a prospective study.

    PubMed

    Napolitano, Mariasanta; Bruno, Aldo; Mastrangelo, Diego; De Vizia, Marcella; Bernardo, Benedetto; Rosa, Buonagura; De Lucia, Domenico

    2014-10-01

    We performed a monocentric observational prospective study to evaluate coagulation activation and endothelial dysfunction parameters in patients with multiple sclerosis undergoing endovascular treatment for cerebro-spinal-venous insufficiency. Between February 2011 and July 2012, 144 endovascular procedures in 110 patients with multiple sclerosis and chronical cerebro-spinal venous insufficiency were performed and they were prospectively analyzed. Each patient was included in the study according to previously published criteria, assessed by the investigators before enrollment. Endothelial dysfunction and coagulation activation parameters were determined before the procedure and during follow-up at 1, 3, 6, 9, 12, 15 and 18 months after treatment, respectively. After the endovascular procedure, patients were treated with standard therapies, with the addition of mesoglycan. Fifty-five percent of patients experienced a favorable outcome of multiple sclerosis within 1 month after treatment, 25% regressed in the following 3 months, 24.9% did not experience any benefit. In only 0.1% patients, acute recurrence was observed and it was treated with high-dose immunosuppressive therapy. No major complications were observed. Coagulation activation and endothelial dysfunction parameters were shown to be reduced at 1 month and stable up to 12-month follow-up, and they were furthermore associated with a good clinical outcome. Endovascular procedures performed by a qualified staff are well tolerated; they can be associated with other currently adopted treatments. Correlations between inflammation, coagulation activation and neurodegenerative disorders are here supported by the observed variations in plasma levels of markers of coagulation activation and endothelial dysfunction.

  1. Inhibition of endotoxin-induced activation of coagulation and fibrinolysis by pentoxifylline or by a monoclonal anti-tissue factor antibody in chimpanzees.

    PubMed

    Levi, M; ten Cate, H; Bauer, K A; van der Poll, T; Edgington, T S; Büller, H R; van Deventer, S J; Hack, C E; ten Cate, J W; Rosenberg, R D

    1994-01-01

    Knowledge of the pathogenetic mechanisms responsible for the activation of the coagulation system associated with endotoxemia is important for the development of improved modalities for prevention and treatment. We analyzed the appearance in plasma of TNF, IL-6, and indices of coagulation and fibrinolytic system activation in normal chimpanzees after intravenous infusion of endotoxin. Endotoxin infusion elicited reproducible and dose-dependent elevations in serum TNF and IL-6, as well as marked increases in thrombin generation in vivo as measured by immunoassays for prothrombin activation fragment F1 + 2, thrombin-antithrombin III complexes, and fibrinopeptide A. Activation of the fibrinolytic mechanism was monitored with assays for plasminogen activator activity and plasmin-alpha 2-antiplasmin complexes. To potentially intervene in the molecular pathways elicited by endotoxin, pentoxifylline, an agent that interrupts "immediate early" gene activation by monocytes, or a potent monoclonal antibody that neutralizes tissue factor-mediated initiation of coagulation, were infused shortly before endotoxin. Pentoxifylline markedly inhibited increases in the levels of TNF and IL-6, as well as the effects on coagulation and fibrinolysis. In contrast, the monoclonal antibody to tissue factor completely abrogated the augmentation in thrombin generation, but had no effect on cytokine levels or fibrinolysis. We conclude that the endotoxin-induced activation of coagulation appears to be mediated by the tissue factor-dependent pathway, the fibrinolytic response triggered by endotoxin is not dependent on the generation of thrombin, and that the release of cytokines may be important in mediating the activation of both the coagulation and the fibrinolytic mechanisms in vivo.

  2. [Cancer procoagulant and cathepsin D activity in blood serum in patients with bladder cancer].

    PubMed

    Szajda, Sławomir Dariusz; Darewicz, Barbara; Kudelski, Jacek; Chlabicz, Marcin; Domel, Tomasz; Chabielska, Ewa; Skrzydlewski, Zdzisław

    2005-06-01

    The increasing morbidity and mortality rates of bladder cancer forced the scientists to search for new unfailing diagnostic and therapeutic methods that will improve treatment effects. There are biochemical cancer markers as cancer procoagulant (CP) and cathepsin D which may be used to this end. The aim of the study was to evaluate the activity of the cancer procoagulant and cathepsin D in the blood serum in patients with superficial bladder cancer. The venous blood samples were from 15 patients with microscopically proved superficial bladder carcinoma (i.e. study group) and 15 normal volunteers as a control group. The serum blood CP activity was determined by the Gordon-Benson's coagulation method and expressed by the clotting time in seconds (s) while the cathepsin D activity was determined by the Folin-Ciocalteau's method and expressed by a quantity of released tyrosine in nmol/ml per 4 hours. The CP activity in serum of patients with superficial bladder cancer was increased in statistically way as compared to the non-cancer controls (p<0.0001). The cathepsin D activity in blood serum of the study group was also enhanced as compared to the control group and the said values differed statistically (p<0.0351). It appears to be justifiable to apply the determination of the CP and cathepsin D activity in blood serum for the diagnostics of superficial bladder cancer.

  3. Effects on coagulation and fibrinolysis induced by influenza in mice with a reduced capacity to generate activated protein C and a deficiency in plasminogen activator inhibitor type 1.

    PubMed

    Keller, Tymen T; van der Sluijs, Koen F; de Kruif, Martijn D; Gerdes, Victor E A; Meijers, Joost C M; Florquin, Sandrine; van der Poll, Tom; van Gorp, Eric C M; Brandjes, Dees P M; Büller, Harry R; Levi, Marcel

    2006-11-24

    Influenza infections increase the risk of diseases associated with a prothrombotic state, such as venous thrombosis and atherothrombotic diseases. However, it is unclear whether influenza leads to a prothrombotic state in vivo. To determine whether influenza activates coagulation, we measured coagulation and fibrinolysis in influenza-infected C57BL/6 mice. We found that influenza increased thrombin generation, fibrin deposition, and fibrinolysis. In addition, we used various anti- and prothrombotic models to study pathways involved in the influenza-induced prothrombotic state. A reduced capacity to generate activated protein C in TM(pro/pro) mice increased thrombin generation and fibrinolysis, whereas treatment with heparin decreased thrombin generation in influenza-infected C57Bl/6 mice. Thrombin generation was not changed in hyperfibrinolytic mice, deficient in plasminogen activator inhibitor type-1 (PAI-1(-/-)); however, increased fibrin degradation was seen. Treatment with tranexamic acid reduced fibrinolysis, but thrombin generation was unchanged. We conclude that influenza infection generates thrombin, increased by reduced levels of protein C and decreased by heparin. The fibrinolytic system appears not to be important for thrombin generation. These findings suggest that influenza leads to a prothrombotic state by coagulation activation. Heparin treatment reduces the influenza induced prothrombotic state. PMID:17068293

  4. Thromboelastometry (TEM) findings in disseminated intravascular coagulation in a pig model of endotoxinemia.

    PubMed

    Schöchl, Herbert; Solomon, Cristina; Schulz, Arthur; Voelckel, Wolfgang; Hanke, Alexander; Van Griensven, Martijn; Redl, Heinz; Bahrami, Soheyl

    2011-01-01

    Standard coagulation tests have a low specificity and sensitivity for diagnosing disseminated intravascular coagulation. The aim of this study was to determine whether whole blood thromboelastometry (TEM) detects lipopolysaccharide (LPS)-induced changes in coagulation. Blood samples from 10 pigs were drawn at baseline, before and at the end of LPS infusion and 2, 3, 4 and 5 h after the start of endotoxinemia. Simultaneous to TEM, standard coagulation tests and extended coagulation analysis including tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) were performed. Endotoxinemia resulted in a significant acceleration of the nonactivated TEM (NATEM) clotting time 2 h after the end of LPS infusion; in contrast, the changes in international normalized ratio and activated partial thromboplastin time suggested delayed initiation of coagulation. NATEM maximum clot firmness (MCF) and fibrin-based thromboelastometry test (FIBTEM)-MCF decreased significantly from baseline until the last time point (from 64.6 ± 7.8 and 35.1 ± 12.8 mm to 52.8 ± 4.6 and 21.4 ± 11.8 mm, respectively; P = 0.01 for both parameters). A sharp, transient increase of t-PA had no effect on maximum lysis in the NATEM test. PAI-1 increased significantly 3 h after the start of LPS infusion, paralleled by a decrease in maximum lysis. In conclusion, TEM was superior to standard coagulation tests in reflecting initial activation of coagulation during endotoxinemia. TEM further suggested consumption of coagulation substrate; at the same time, inhibition of plasminogen activation was accompanied by improved clot stability. Further investigations are necessary to establish the clinical relevance of these findings.

  5. Coagulation tests show significant differences in patients with breast cancer.

    PubMed

    Tas, Faruk; Kilic, Leyla; Duranyildiz, Derya

    2014-06-01

    Activated coagulation and fibrinolytic system in cancer patients is associated with tumor stroma formation and metastasis in different cancer types. The aim of this study is to explore the correlation of blood coagulation assays for various clinicopathologic factors in breast cancer patients. A total of 123 female breast cancer patients were enrolled into the study. All the patients were treatment naïve. Pretreatment blood coagulation tests including PT, APTT, PTA, INR, D-dimer, fibrinogen levels, and platelet counts were evaluated. Median age of diagnosis was 51 years old (range 26-82). Twenty-two percent of the group consisted of metastatic breast cancer patients. The plasma level of all coagulation tests revealed statistically significant difference between patient and control group except for PT (p<0.001 for all variables except for PT; p=0.08). Elderly age (>50 years) was associated with higher D-dimer levels (p=0.003). Metastatic patients exhibited significantly higher D-dimer values when compared with early breast cancer patients (p=0.049). Advanced tumor stage (T3 and T4) was associated with higher INR (p=0.05) and lower PTA (p=0.025). In conclusion, coagulation tests show significant differences in patients with breast cancer.

  6. Poly(γ-glutamic acid), coagulation? Anticoagulation?

    PubMed

    Xu, Tingting; Peng, Fang; Zhang, Tao; Chi, Bo; Xu, Hong; Mao, Chun; Feng, Shuaihui

    2016-11-01

    Poly(γ-glutamic acid) (γ-PGA) powder was usually used as hemostatic agent because of its excellent physical properties of water-absorption and water-locking. However, if γ-PGA absorbs enough water, how about its blood compatibility? Here, the other side of the coin was investigated. The anticoagulant properties of γ-PGA were characterized by in vitro coagulation tests, hemolytic assay, platelet adhesion, and platelet activation. Moreover, cytotoxicity experiments of γ-PGA were also carried out by MTT assay. Results indicated that the sufficient water-absorbed γ-PGA has good anticoagulant property and non-cytotoxicity. It means γ-PGA has good anticoagulant property, non-cytotoxicity. If γ-PGA has absorbed enough water, it can be used as an anticoagulation biomaterial. With double effects (coagulation and anticoagulation), the γ-PGA with desirable bioproperties can be readily tailored to cater to various biomedical applications. PMID:27545694

  7. [Disseminated intravascular coagulation: clinical and biological diagnosis].

    PubMed

    Touaoussa, Aziz; El Youssi, Hind; El Hassani, Imane; Hanouf, Daham; El Bergui, Imane; Zoulati, Ghizlane; Amrani Hassani, Moncef

    2015-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by the systemic activation of blood coagulation. Its pathophysiological mechanisms are complex and dependent on the underlying pathology, making the clinical and biological expression of quite variable DIC. Among the various biological parameters disrupted, most are not specific, and none of them allows in itself to make the diagnosis. All this does not facilitate the task of the practitioner for diagnosis of overt DIC, much less that of the non-overt DIC, early stage whose treatment would improve the prognosis. These considerations have led to develop scores, combining several parameters depending on their availability in daily practice, as well as their diagnostic relevance. Of all the scores, the ISTH (International society of thrombosis and hemostasis) remains the most used.

  8. Poultry blood preservation and the impact of preservation on flocculant activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken blood is an attractive but problematic raw material for the production of biobased flocculants. Blood begins to degrade as soon as it is collected – it rapidly coagulates, and at longer time scales, the red blood cells lyse and microbial growth results in hydrogen sulfide production. This s...

  9. Cancer procoagulant and blood platelet activation.

    PubMed

    Olas, B; Wachowicz, B; Mielicki, W P

    2001-08-28

    The effects of cancer procoagulant (CP), cysteine protease (EC 3.4.22.26), on the pig blood platelet secretory process and platelet aggregation have been studied. The response of platelets to CP was compared with the response of these cells to thrombin. The obtained results show that blood platelets treated with CP (0.5, 1, 2.5, and 5 microg/ml, 2-30 min, 37 degrees C) released adenine nucleotides (P < 0.05) and proteins (P < 0.05). The secretion of compounds from blood platelets after incubation with CP does not correlate with the release of platelet lactic dehydrogenase activity (marker of cell lysis) into the extracellular medium. In comparison with thrombin action, CP stimulates secretory process to a smaller extent than thrombin alone. In the presence of CP, the thrombin action is suppressed (P < 0.05). We noticed that CP does not induce platelet aggregation.

  10. Coagulation disorders in septic shock.

    PubMed

    Thijs, L G; de Boer, J P; de Groot, M C; Hack, C E

    1993-01-01

    Abnormalities in coagulation and fibrinolysis are frequently observed in septic shock. The most pronounced clinical manifestation is disseminated intravascular coagulation. Recent studies in human volunteers and animal models have clarified the early dynamics and route of activation of both coagulation and fibrinolytic pathways. In healthy subjects subjected to a low dose of either endotoxin or TNF an imbalance in the procoagulant and the fibrinolytic mechanisms is apparent, resulting in a procoagulant state. Also in patients with septic shock a dynamic process of coagulation and fibrinolysis is ongoing with evidence of impaired fibrinolysis. These abnormalities have prognostic significance; the extent of disturbances of coagulation and fibrinolysis is related to the development of multiple organ failure and death.

  11. Obstetrical disseminated intravascular coagulation score.

    PubMed

    Kobayashi, Takao

    2014-06-01

    Obstetrical disseminated intravascular coagulation (DIC) is usually a very acute, serious complication of pregnancy. The obstetrical DIC score helps with making a prompt diagnosis and starting treatment early. This DIC score, in which higher scores are given for clinical parameters rather than for laboratory parameters, has three components: (i) the underlying diseases; (ii) the clinical symptoms; and (iii) the laboratory findings (coagulation tests). It is justifiably appropriate to initiate therapy for DIC when the obstetrical DIC score reaches 8 points or more before obtaining the results of coagulation tests. Improvement of blood coagulation tests and clinical symptoms are essential to the efficacy evaluation for treatment after a diagnosis of obstetrical DIC. Therefore, the efficacy evaluation criteria for obstetrical DIC are also defined to enable follow-up of the clinical efficacy of DIC therapy.

  12. Heparins with reduced anti-coagulant activity reduce myocardial reperfusion injury.

    PubMed

    Barry, William H; Kennedy, Thomas P

    2011-05-01

    Heparin which is desulfated at the 2-O and 3-O positions (ODSH) has reduced anti-coagulant properties, and reduced interaction with heparin antibodies. Because of the reduced anti-coagulant effect, ODSH can be safely administered to animals and humans intravenously at doses up to 20 mg/kg, resulting in a serum concentration of up to 250µg/ml. Administration of ODSH causes a 35% reduction in infarct size in dogs and pigs subjected to coronary artery occlusion and reperfusion when given 5 min before reperfusion. ODSH has anti-inflamatory effects, manifest as a decrease in neutrophil infiltration into ischemic tissue at high doses, but this effect does not entirely account for the reduction in infarct size. ODSH decreases Na(+) and Ca(2+) loading in isolated cardiac myocytes subjected to simulated ischemia. This effect appears due to an ODSH-induced reduction in an enhanced Na(+) influx via the Na channel in the membrane of cardiac myocyes caused by oxygen radicals generated during ischemia and reperfusion. Reduction in Na(+) influx decreases Ca(2+) loading by reducing Ca2(+) influx via Na/Ca exchange, thus reducing Ca(2+) - dependent reperfusion injury. ODSH does not appear to interact with antibodies to the heparin/platelet factor 4 complex, and does not cause heparin-induced thrombocytopenia. Because of these therapeutic and safety considerations, ODSH would appear to be a promising heparin derivative for prevention of reperfusion injury in humans undergoing thrombolytic or catheter-based reperfusion for acute myocardial infarction. The review article discussed the use of heparin and the discussion of some of the important patents, including: US6489311; US7478358; PCTUS2008070836 and PCTUS2009037836.

  13. More efficient reversal of dabigatran inhibition of coagulation by activated prothrombin complex concentrate or recombinant factor VIIa than by four-factor prothrombin complex concentrate.

    PubMed

    Lindahl, Tomas L; Wallstedt, Maria; Gustafsson, Kerstin M; Persson, Egon; Hillarp, Andreas

    2015-03-01

    The number of patients on antithrombotic treatment due to atrial fibrillation and venous thromboembolism is increasing fast due to an aging population. A growing proportion will be treated with novel oral anticoagulants, the first in clinical use was the direct oral thrombin inhibitor dabigatran (Pradaxa®). A small percentage of the patients on dabigatran will experience serious bleeding or be in need of urgent surgery. The aim of this study was to test the effects of different hemostatic agents in potentially reversing the anticoagulant effects in vitro in blood or platelet-rich plasma (PRP) spiked with dabigatran. Whole blood or PRP was spiked with the active substance dabigatran, 200 μg/L. We measured clotting time being induced by 1.4 pmol/L tissue factor using the instrument ReoRox2™ and initial clot growth velocity from a tissue factor covered surface using the instrument Thrombodynamics Analyzer T-2™. Dabigatran prolonged clotting time 5-fold but reduced clot growth velocity only slightly. The reversing effects of prothrombin complex concentrates (PCC), activated PCC (APCC) and recombinant activated factor VII (rFVIIa) were then tested. APCC (1.8 U/mL) reduced the prolonged clotting time by 1/3, rFVIIa (2 μg/L) only slightly (n = 10-20). The reduction was not significant using Mann-Whitney test but significant using t-test with Bonferronis' correction for multiple comparisons, whereas PCC (0.56 U/mL) had no effect on clotting time. APCC doubled initial clot growth velocity, although even more in the absence of dabigatran. In conclusion, APCC and rFVIIa, but not PCC, seem to reverse, at least partially, some effects of dabigatran on coagulation parameters. Systematic evaluation of case reports, registries and, ultimately, randomized clinical trials are needed to elucidate potential benefit for patients.

  14. Impact of coagulation as a pre-treatment for UVC/H2O2-biological activated carbon treatment of a municipal wastewater reverse osmosis concentrate.

    PubMed

    Umar, Muhammad; Roddick, Felicity; Fan, Linhua

    2016-01-01

    After coagulation of high salinity reverse osmosis concentrate (ROC) with either alum or ferric chloride followed by UVC/H2O2 treatment, biological activated carbon (BAC) was investigated for the removal of DOC. BAC treatment mainly removed low molecular weight (LMW) neutral molecules indicating that biodegradation was the predominant mechanism of organic matter removal. Coagulation with ferric chloride gave greater DOC reductions than alum both as a stand-alone treatment and after the sequence of UVC/H2O2 and BAC treatment. However, overall reduction after the sequence of coagulation, UVC/H2O2 and BAC treatment was only marginally greater for ferric chloride (68%) than for alum (62%). Trihalomethane formation potential and N-Nitrosodimethylamine concentration decreased markedly after UVC/H2O2 treatment. UVC/H2O2 treatment of the ROC led to the generation of extreme toxicity according to the Microtox assay, but no toxicity was observed after BAC, demonstrating its advantage for enabling safe disposal of the treated ROC. Implementation of coagulation as a pre-treatment and BAC as a post-treatment markedly reduced (6-8 times) the electrical energy dose (EED) required for the UVC/H2O2 process. The sequence of coagulation, UVC/H2O2 and BAC treatment was demonstrated as a potential process for the removal of organic matter from high salinity municipal ROC.

  15. Impact of coagulation as a pre-treatment for UVC/H2O2-biological activated carbon treatment of a municipal wastewater reverse osmosis concentrate.

    PubMed

    Umar, Muhammad; Roddick, Felicity; Fan, Linhua

    2016-01-01

    After coagulation of high salinity reverse osmosis concentrate (ROC) with either alum or ferric chloride followed by UVC/H2O2 treatment, biological activated carbon (BAC) was investigated for the removal of DOC. BAC treatment mainly removed low molecular weight (LMW) neutral molecules indicating that biodegradation was the predominant mechanism of organic matter removal. Coagulation with ferric chloride gave greater DOC reductions than alum both as a stand-alone treatment and after the sequence of UVC/H2O2 and BAC treatment. However, overall reduction after the sequence of coagulation, UVC/H2O2 and BAC treatment was only marginally greater for ferric chloride (68%) than for alum (62%). Trihalomethane formation potential and N-Nitrosodimethylamine concentration decreased markedly after UVC/H2O2 treatment. UVC/H2O2 treatment of the ROC led to the generation of extreme toxicity according to the Microtox assay, but no toxicity was observed after BAC, demonstrating its advantage for enabling safe disposal of the treated ROC. Implementation of coagulation as a pre-treatment and BAC as a post-treatment markedly reduced (6-8 times) the electrical energy dose (EED) required for the UVC/H2O2 process. The sequence of coagulation, UVC/H2O2 and BAC treatment was demonstrated as a potential process for the removal of organic matter from high salinity municipal ROC. PMID:26454666

  16. Chronic urticaria and coagulation: pathophysiological and clinical aspects.

    PubMed

    Tedeschi, A; Kolkhir, P; Asero, R; Pogorelov, D; Olisova, O; Kochergin, N; Cugno, M

    2014-06-01

    Chronic urticaria (CU) is a widespread skin disease, characterized by the recurrence of transient wheals and itch for more than 6 weeks. Besides autoimmune mechanisms, coagulation factors, in particular tissue factor and thrombin, might also participate in the disease pathophysiology. Tissue factor expressed by eosinophils can induce activation of blood coagulation generating thrombin which in turn can increase vascular permeability both directly, acting on endothelial cells, and indirectly, inducing degranulation of mast cells with release of histamine, as demonstrated in experimental models. D-dimer, a fibrin degradation product, generated following activation of the coagulation cascade and fibrinolysis, has been found to be increased during urticaria exacerbations; moreover, it has been proposed as a biomarker of severity and resistance to H1-antihistamines in CU patients. The possible role of coagulation in CU is also supported by case reports, case series and a small controlled study showing the efficacy of anticoagulant therapy in this disease. The purpose of this review was to summarize the available data on the possible contribution of coagulation to the pathophysiology of CU focusing on clinical aspects and possible future therapeutic developments. PMID:24673528

  17. Complement-Coagulation Cross-Talk: A Potential Mediator of the Physiological Activation of Complement by Low pH

    PubMed Central

    Kenawy, Hany Ibrahim; Boral, Ismet; Bevington, Alan

    2015-01-01

    The complement system is a major constituent of the innate immune system. It not only bridges innate and adaptive arms of the immune system but also links the immune system with the coagulation system. Current understanding of the role of complement has extended far beyond fighting of infections, and now encompasses maintenance of homeostasis, tissue regeneration, and pathophysiology of multiple diseases. It has been known for many years that complement activation is strongly pH sensitive, but only relatively recently has the physiological significance of this been appreciated. Most complement assays are carried out at the physiological pH 7.4. However, pH in some extracellular compartments, for example, renal tubular fluid in parts of the tubule, and extracellular fluid at inflammation loci, is sufficiently acidic to activate complement. The exact molecular mechanism of this activation is still unclear, but possible cross-talk between the contact system (intrinsic pathway) and complement may exist at low pH with subsequent complement activation. The current article reviews the published data on the effect of pH on the contact system and complement activity, the nature of the pH sensor molecules, and the clinical implications of these effects. Of particular interest is chronic kidney disease (CKD) accompanied by metabolic acidosis, in which therapeutic alkalinization of urine has been shown significantly to reduce tubular complement activation products, an effect, which may have important implications for slowing progression of CKD. PMID:25999953

  18. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    PubMed

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

  19. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    PubMed

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

  20. Plasminogen activator and plasminogen activator inhibitor I release during experimental endotoxaemia in chimpanzees: effect of interventions in the cytokine and coagulation cascades.

    PubMed

    Biemond, B J; Levi, M; Ten Cate, H; Van der Poll, T; Büller, H R; Hack, C E; Ten Cate, J W

    1995-05-01

    1. Disseminated intravascular coagulation frequently accompanies Gram-negative sepsis and may contribute to widespread deposition of microthrombi. Besides the endotoxin-induced activation of coagulation, an important role for the fibrinolytic system has been postulated. The precise mechanisms underlying these fibrinolytic changes during endotoxaemia are not known but have been suggested to be mediated directly by cytokines or secondary to thrombin generation. 2. In the present study we have delineated in detail the fibrinolytic response to a bolus injection of endotoxin in non-human primates and analysed the contribution of cytokines and thrombin generation to the endotoxin-induced release of tissue-type plasminogen activator and plasminogen activator inhibitor 1. Chimpanzees received a bolus injection of endotoxin alone or in combination with blocking monoclonal antibodies directed against tumour necrosis factor or interleukin 6 or in combination with pentoxifylline. Furthermore, to assess the effect of coagulation activation on the activation of fibrinolysis, another group of chimpanzees received endotoxin in combination with either anti-tissue factor antibodies or recombinant hirudin. 3. Infusion of endotoxin induced a rapid increase in plasminogen activator activity and tissue-type plasminogen activator antigen levels and subsequent plasmin generation, reaching peak levels 2h after endotoxin administration. Plasminogen activator inhibitor 1 levels remained constant for the first 2 h, after which time a steep increase was observed. Plasminogen activator activity and plasmin generation decreased simultaneously with the rise in plasminogen activator inhibitor 1 levels. Fibrinolytic activity remained suppressed during the remainder of the study owing to sustained increased levels of plasminogen activator inhibitor 1. The administration of pentoxifylline strongly attenuated the release of tissue-type plasminogen activator and plasminogen activator inhibitor 1

  1. Hydroxyurea increases plasma concentrations of microparticles and reduces coagulation activation and fibrinolysis in patients with sickle cell anemia.

    PubMed

    Brunetta, Denise Menezes; De Santis, Gil Cunha; Silva-Pinto, Ana Cristina; Oliveira de Oliveira, Luciana Correa; Covas, Dimas Tadeu

    2015-01-01

    Microparticles (MPs) are present in healthy subjects and their concentration increases in patients at high risk of thrombosis. We evaluated 10 patients with sickle cell anemia (SCA) treated with hydroxyurea (HU) and 13 SCA patients without this treatment. MP concentrations were determined by flow cytometry. Coagulation was evaluated using the thrombin-antithrombin complex (TAT) and D-dimers. Total MP concentrations were increased in the HU-treated group (265 × 10(6)/ml vs. 67.45 × 10(6)/ml; p = 0.0026), as well as MPs derived from RBC (67.83 × 10(6)/ml vs. 26.31 × 10(6)/ml; p = 0.05), monocytes (51.31 × 10(6)/ml vs. 9.03 × 10(6)/ml; p = 0.0084), monocytes with tissue factor (TF) expression (2.27 × 10(6)/ml vs. 0.27 × 10(6)/ml; p = 0.0058), endothelium (49.42 × 10(6)/ml vs. 7.23 × 10(6)/ml; p = 0.007) and endothelium with TF (1.42 × 10(6)/ml vs. 0.26 × 10(6)/ml; p = 0.0043). Furthermore, the concentrations of TAT (7.56 vs. 10.98 µg/l; p = 0.014) and D-dimers (0.65 vs. 1.29 µg/ml; p = 0.007) were reduced with HU. The MP elevation may suggest a direct cytotoxic effect of HU. Another explanation is a cell surface increase secondary to a megaloblastic process, resulting in increased vesicle release. In our opinion, the known benefits of HU on SCA patients, along with the reduction in coagulation activation, surpass its potential detrimental effect on MPs. Future studies should elucidate the role of MPs and demonstrate their significance in different contexts. PMID:25472687

  2. Preliminary assessment of Hedychium coronarium essential oil on fibrinogenolytic and coagulant activity induced by Bothrops and Lachesis snake venoms

    PubMed Central

    2014-01-01

    Background The search for new inhibitors of snake venom toxins is essential to complement or even replace traditional antivenom therapy, especially in relation to compounds that neutralize the local effects of envenomations. Besides their possible use as alternative to traditional antivenom therapy, some plant species possess bioactive secondary metabolites including essential oils, which can be extracted from weeds that are considered substantial problems for agriculture, such as Hedychium coronarium. Methods The essential oils of leaves and rhizomes from H. coronarium were extracted by hydrodistillation, and their potential inhibitory effects on the coagulant and fibrinogenolytic activities induced by the venoms of Lachesis muta, Bothrops atrox and Bothrops moojeni were analyzed. Citrated human plasma was used to evaluate the clotting time whereas changes in fibrinogen molecules were visualized by electrophoresis in polyacrylamide gel. The experimental design used for testing coagulation inhibition was randomized in a 3 × 2 factorial arrangement (concentration × essential oils), with three replications. The essential oils were compared since they were extracted from different organs of the same botanical species, H. coronarium. Results The results suggest that the oils interact with venom proteases and plasma constituents, since all oils evaluated, when previously incubated with venoms, were able to inhibit the clotting effect, with less inhibition when oils and plasma were preincubated prior to the addition of venoms. Conclusions Thus, after extensive characterization of their pharmacological and toxicological effects, the essential oils can be used as an alternative to complement serum therapy, especially considering that these plant metabolites generally do not require specific formulations and may be used topically immediately after extraction. PMID:26413083

  3. The effect of hyperglycemia on blood coagulation: In vitro, observational healthy-volunteer study using rotational thromboelastometry (ROTEM).

    PubMed

    Shin, Hyun-Jung; Na, Hyo-Seok; Lee, Soowon; Lee, Gwan-Woo; Do, Sang-Hwan

    2016-08-01

    We performed a study to investigate whether contamination of hemostasis samples with a glucose-containing solution might generate spurious results in rotational thromboelastometry (ROTEM) tests.Venous blood was taken from 12 healthy volunteers and divided into 4 specimen bottles, which were contaminated with different concentrations (0%, 5%, 10%, and 20%) of glucose solution.Significant lengthening of INTEMCT was observed in the 10% and 20% groups compared with baseline values (7.7% and 9%, P = 0.041 and P = 0.037, respectively). INTEMCFT increased by 20.1% in the 20% group (P = 0.005). INTEMα-angle and INTEMMCF decreased by 3.9% and 2.7%, respectively, in the 20% group (P = 0.010 and P = 0.049, respectively). EXTEMCFT was prolonged significantly, by 10.2%, 15.5%, and 25.6%, in the 5%, 10%, and 20% groups, respectively (P = 0.004, P < 0.001, and P < 0.001, respectively). EXTEMα-angle decreased significantly by 1.9%, 3.2%, and 4.0% in the 5%, 10%, and 20% groups, respectively (P = 0.014, P = 0.001, and P = 0.005, respectively). EXTEMMCF decreased by 3.4% in the 20% group (P = 0.023). FIBTEMMCF decreased by 9.2% and 17.5% in the 10% and 20% groups, respectively (P = 0.019 and P = 0.021, respectively). A significant correlation was observed between standard glucose solution contamination in the specimens and percentage variation of EXTEMCFT, EXTEMMCF, and FIBTEMMCF.To obtain accurate data from the ROTEM test regarding the hemostatic status of patients, specimens with suspected or known contamination should not be analyzed. PMID:27583903

  4. The effect of hyperglycemia on blood coagulation: In vitro, observational healthy-volunteer study using rotational thromboelastometry (ROTEM)

    PubMed Central

    Shin, Hyun-Jung; Na, Hyo-Seok; Lee, Soowon; Lee, Gwan-Woo; Do, Sang-Hwan

    2016-01-01

    Abstract We performed a study to investigate whether contamination of hemostasis samples with a glucose-containing solution might generate spurious results in rotational thromboelastometry (ROTEM) tests. Venous blood was taken from 12 healthy volunteers and divided into 4 specimen bottles, which were contaminated with different concentrations (0%, 5%, 10%, and 20%) of glucose solution. Significant lengthening of INTEMCT was observed in the 10% and 20% groups compared with baseline values (7.7% and 9%, P = 0.041 and P = 0.037, respectively). INTEMCFT increased by 20.1% in the 20% group (P = 0.005). INTEMα-angle and INTEMMCF decreased by 3.9% and 2.7%, respectively, in the 20% group (P = 0.010 and P = 0.049, respectively). EXTEMCFT was prolonged significantly, by 10.2%, 15.5%, and 25.6%, in the 5%, 10%, and 20% groups, respectively (P = 0.004, P < 0.001, and P < 0.001, respectively). EXTEMα-angle decreased significantly by 1.9%, 3.2%, and 4.0% in the 5%, 10%, and 20% groups, respectively (P = 0.014, P = 0.001, and P = 0.005, respectively). EXTEMMCF decreased by 3.4% in the 20% group (P = 0.023). FIBTEMMCF decreased by 9.2% and 17.5% in the 10% and 20% groups, respectively (P = 0.019 and P = 0.021, respectively). A significant correlation was observed between standard glucose solution contamination in the specimens and percentage variation of EXTEMCFT, EXTEMMCF, and FIBTEMMCF. To obtain accurate data from the ROTEM test regarding the hemostatic status of patients, specimens with suspected or known contamination should not be analyzed. PMID:27583903

  5. Coagulation in patients with severe sepsis.

    PubMed

    Levi, Marcel; Poll, Tom van der

    2015-02-01

    In the majority of patients with severe sepsis, systemic activation of coagulation is present. Increasing evidence points to an extensive cross-talk between coagulation and inflammation that may play an important role in the pathogenesis of sepsis. Inflammation not only leads to activation of coagulation, but coagulation also considerably affects inflammatory activity. Molecular pathways that contribute to inflammation-induced activation of coagulation have been precisely identified. Proinflammatory cytokines and other mediators are capable of activating the coagulation system and downregulating important physiological anticoagulant pathways. Activation of the coagulation system and ensuing thrombin generation is dependent on expression of tissue factor on activated mononuclear cells and endothelial cells, and is insufficiently counteracted by TFPI. Simultaneously, endothelial-bound anticoagulant mechanism, in particular the protein C system, is shutoff by proinflammatory cytokines. In addition, fibrin removal is severely inhibited, because of inactivation of the fibrinolytic system, caused by an upregulation of its main inhibitor, plasminogen activator inhibitor type 1 (PAI-1). Increased fibrin formation and impaired removal lead to (micro)vascular thrombosis, which may result in tissue ischemia and subsequent organ damage. The cornerstone of the management of coagulation in sepsis is the specific and vigorous treatment of the underlying disorder. Strategies aimed at the inhibition of coagulation activation may theoretically be justified and have been found beneficial in experimental and initial clinical studies. Heparin may be an effective anticoagulant approach and alternative strategies comprise restoration of physiological anticoagulant pathways. PMID:25590524

  6. Asthma and coagulation.

    PubMed

    de Boer, J Daan; Majoor, Christof J; van 't Veer, Cornelis; Bel, Elisabeth H D; van der Poll, Tom

    2012-04-01

    Asthma is a chronic airway disease characterized by paroxysmal airflow obstruction evoked by irritative stimuli on a background of allergic lung inflammation. Currently, there is no cure for asthma, only symptomatic treatment. In recent years, our understanding of the involvement of coagulation and anticoagulant pathways, the fibrinolytic system, and platelets in the pathophysiology of asthma has increased considerably. Asthma is associated with a procoagulant state in the bronchoalveolar space, further aggravated by impaired local activities of the anticoagulant protein C system and fibrinolysis. Protease-activated receptors have been implicated as the molecular link between coagulation and allergic inflammation in asthma. This review summarizes current knowledge of the impact of the disturbed hemostatic balance in the lungs on asthma severity and manifestations and identifies new possible targets for asthma treatment.

  7. Coagulation in Liver Disease.

    PubMed

    Hoffman, Maureane

    2015-07-01

    The liver plays a key role in hemostasis as the site of synthesis of many of the proteins involved in the coagulation, antithrombotic and fibrinolytic systems that interact to both establish hemostasis, and preventing thrombosis. The common laboratory tests, prothrombin time (PT) and activated partial thromboplastin time (aPTT), evolved from studies of plasma clotting in test tubes. Such studies laid the basis for the coagulation cascade model of hemostasis. However, thought has evolved to place a greater emphasis on the active roles of cells in localizing and regulating hemostasis. The PT and aPTT do not reflect the roles of cellular elements in hemostasis, nor do they reflect the crucial roles of antithrombotic and fibrinolytic systems. Thus, though the PT may indeed reflect the synthetic capacity of the liver, it does not accurately reflect the risk of bleeding or thrombosis in patients with liver failure.

  8. Asthma and coagulation.

    PubMed

    de Boer, J Daan; Majoor, Christof J; van 't Veer, Cornelis; Bel, Elisabeth H D; van der Poll, Tom

    2012-04-01

    Asthma is a chronic airway disease characterized by paroxysmal airflow obstruction evoked by irritative stimuli on a background of allergic lung inflammation. Currently, there is no cure for asthma, only symptomatic treatment. In recent years, our understanding of the involvement of coagulation and anticoagulant pathways, the fibrinolytic system, and platelets in the pathophysiology of asthma has increased considerably. Asthma is associated with a procoagulant state in the bronchoalveolar space, further aggravated by impaired local activities of the anticoagulant protein C system and fibrinolysis. Protease-activated receptors have been implicated as the molecular link between coagulation and allergic inflammation in asthma. This review summarizes current knowledge of the impact of the disturbed hemostatic balance in the lungs on asthma severity and manifestations and identifies new possible targets for asthma treatment. PMID:22262775

  9. Advances in Oral Coagulants

    PubMed Central

    2013-01-01

    This article reviews current and future treatment practices concerning oral anticoagulants. In the second decade of the 21st millennium clinicians can finally treat thrombotic disease with long-awaited new oral anticoagulant medications. In addition, improvements have been made in managing warfarin, the traditional but far from obsolete medication. The first part of this review will cover current advances with warfarin treatment. The second portion will discuss specific active coagulation factor inhibitors, the new oral anticoagulants.

  10. Disseminated intravascular coagulation.

    PubMed

    Gando, Satoshi; Levi, Marcel; Toh, Cheng-Hock

    2016-01-01

    Disseminated intravascular coagulation (DIC) is an acquired syndrome characterized by widespread intravascular activation of coagulation that can be caused by infectious insults (such as sepsis) and non-infectious insults (such as trauma). The main pathophysiological mechanisms of DIC are inflammatory cytokine-initiated activation of tissue factor-dependent coagulation, insufficient control of anticoagulant pathways and plasminogen activator inhibitor 1-mediated suppression of fibrinolysis. Together, these changes give rise to endothelial dysfunction and microvascular thrombosis, which can cause organ dysfunction and seriously affect patient prognosis. Recent observations have pointed to an important role for extracellular DNA and DNA-binding proteins, such as histones, in the pathogenesis of DIC. The International Society on Thrombosis and Haemostasis (ISTH) established a DIC diagnostic scoring system consisting of global haemostatic test parameters. This scoring system has now been well validated in diverse clinical settings. The theoretical cornerstone of DIC management is the specific and vigorous treatment of the underlying conditions, and DIC should be simultaneously managed to improve patient outcomes. The ISTH guidance for the treatment of DIC recommends treatment strategies that are based on current evidence. In this Primer, we provide an updated overview of the pathophysiology, diagnosis and management of DIC and discuss the future directions of basic and clinical research in this field. PMID:27250996

  11. Toward a better understanding of coagulation for dissolved organic nitrogen using polymeric zinc-iron-phosphate coagulant.

    PubMed

    Zhu, Guocheng; Wang, Qian; Yin, Jun; Li, Zhongwu; Zhang, Peng; Ren, Bozhi; Fan, Gongduan; Wan, Peng

    2016-09-01

    The increase of agricultural related activities and the lack of effective waste control has led to an increase of organic nitrogen in water. The development of coagulants to effectively remove dissolved organic nitrogen (DON) is a high priority in the water treatment industry. We developed a polymeric zinc-iron-phosphate (ZnFeP) coagulant and investigated its coagulation effect on DON removal. Optimum coagulant for coagulation for DON and TDN removals was characterized by the dense convex-concave packing structure differing from other zinc-based coagulant, polycrystalline structure and high content colloidal species, which could account up to 87% of the total colloidal species. Coagulation experiments showed the DON removal rate to vary greatly depending on principal components and their interaction with metals, phosphate and hydroxyl. DON removal efficiency increased with the increase of colloidal species. The coagulation was also dependent on coagulant dosage and water quality parameters: Coagulation efficiency increased with coagulant dosage in the investigated range of 1-16 mg/l, and a pH of 6 was found to be superior for the coagulation. DON removal efficiency was also higher than and linearly correlated with total dissolved nitrogen (TDN) removal, which implies that an effective coagulation for TDN is also effective for DON. The findings in this study indicate that coagulation of DON is largely influenced by coagulant composition and species. We also found the removal of DON by our newly developed polymeric ZnFeP coagulant to be effective. PMID:27192355

  12. Prehospital coagulation monitoring of resuscitation with point-of-care devices.

    PubMed

    Schött, Ulf

    2014-05-01

    A variety of point-of-care monitors for the measurement of hematocrit, hemoglobin, blood gas with electrolytes, and lactate can be used also in the prehospital setting for optimizing and individualizing trauma resuscitation. Point-of-care coagulation testing with activated prothrombin test, prothrombin test, and activated coagulation/clotting time tests is available for prehospital use. Although robust, battery driven, and easy to handle, many devices lack documentation for use in prehospital care. Some of the devices correspond poorly to corresponding laboratory analyses in acute trauma coagulopathy and at lower hematocrits. In trauma, viscoelastic tests such as rotational thromboelastometry and thromboelastography can rapidly detect acute trauma coagulopathy and give an overall dynamic picture of the hemostatic system and the interaction between its different components: coagulation activation, fibrin polymerization, fibrin platelet interactions within the clot, and fibrinolysis. Rotational thromboelastometry is shock resistant and has the potential to be used outside the hospital setting to guide individualized coagulation factor and blood component therapies. Sonoclot and Rheorox are two small viscoelastic instruments with one-channel options, but with less documentation. The point-of-care market for coagulation tests is quickly expanding, and new devices are introduced all the time. Still they should be better adopted to prehospital conditions, small, robust, battery charged, and rapid and use small sample volumes and whole blood.

  13. Neutrophil elastase cleavage of human factor IX generates an activated factor IX-like product devoid of coagulant function.

    PubMed

    Samis, J A; Kam, E; Nesheim, M E; Giles, A R

    1998-08-15

    , respectively. In summary, the results suggest that the activatability of F.IX is eliminated after cleavage by HNE and that the inability of HNE-treated F.IX to support F.IXa-like coagulant function is a consequence of improper active site formation. These in vitro observations support the possibility that increased HNE cleavage of F.IX in vivo may contribute to the disregulation of hemostasis that occurs in conditions such as disseminated intravascular coagulation (DIC). PMID:9694717

  14. A comparative study on the efficiency of ozonation and coagulation-flocculation as pretreatment to activated carbon adsorption of biologically stabilized landfill leachate.

    PubMed

    Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim T M; Demeestere, Kristof; Van Hulle, Stijn W H

    2015-09-01

    The present work investigates the potential of coagulation-flocculation and ozonation to pretreat biologically stabilized landfill leachate before granular activated carbon (GAC) adsorption. Both iron (III) chloride (FeCl3) and polyaluminium chloride (PACl) are investigated as coagulants. Better organic matter removal is observed when leachate was treated with FeCl3. At a dose of 1mg FeCl3/mg CODo (CODo: initial COD content), the COD and α254 removal was 66% and 88%, respectively. Dosing 1mg PACl/mg CODo resulted in 44% COD and 72% α254 removal. The settle-ability of sludge generated by PACl leveled off at 252mL/g, while a better settle-ability of 154mL/g was obtained for FeCl3 after dosing 1mg coagulant/mg CODo. For ozonation, the percentage of COD and α254 removal increased as the initial COD concentration decreased. Respectively 44% COD and 77% α254 removal was observed at 112mg COD/L compared to 5% COD and 26% α254 removal at 1846mg COD/L. Subsequent activated carbon adsorption of ozonated, coagulated and untreated leachate resulted in 77%, 53% and 8% total COD removal after treatment of 6 bed volumes. Clearly showing the benefit of treating the leachate before GAC adsorption. Mathematical modeling of the experimental GAC adsorption data with Thomas and Yoon-Nelson models show that ozonation increases the adsorption capacity and breakthrough time of GAC by a factor of 2.5 compared to coagulation-flocculation.

  15. Structural Features and Anti-coagulant Activity of the Sulphated Polysaccharide SPS-CF from a Green Alga Capsosiphon fulvescens.

    PubMed

    Synytsya, Andriy; Choi, Doo Jin; Pohl, Radek; Na, Ye Seul; Capek, Peter; Lattová, Erika; Taubner, Tomáš; Choi, Ji Won; Lee, Chang Won; Park, Jae Kweon; Kim, Woo Jung; Kim, Sung Min; Lee, Jisun; Park, Yong Il

    2015-12-01

    Previously, we reported that the sulphated polysaccharides (SPS)-CF, a water-soluble polysaccharide isolated and purified from Korean green alga Maesaengi (Capsosiphon fulvescens, Chlorophyta), is a glucuronogalactomannan based mainly on the monosaccharide composition determined by high-performance liquid chromatography (HPLC) analysis after 1-phenyl-3-methyl-5-pyrazolone (PMP) labelling of sugars in the acid (trifluoroacetic acid (TFA)) hydrolyzates of SPS-CF, which showed mannose (55.4 mol %), galactose (25.3 mol %) and glucuronic acid (16.3 mol %) as major sugars (Na et al., Int Immunopharmacol 10:364-370, 2010). However, the results of the present study re-performed for monosaccharide composition of this polysaccharide using, in addition to HPLC of PMP-labelled sugars, other separation methods, i.e. high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), gas chromatography with flame ionising detection (GC-FID) and thin-layer chromatography (TLC), clearly demonstrated that the most prominent neutral monosaccharides of SPS-CF are xylose (38.6-49.4 mol %) and rhamnose (39.6-45 mol %), while mannose and galactose are present at a much lesser extent or in negligible amount. These extensive monosaccharide analyses, correlation nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) measurements confirmed the sulphated glucuronorhamnoxylan (ulvan) type of SPS-CF polysaccharide, whose backbone is composed of alternating sequence of 4-linked L-rhamnose-3-sulphate and D-xylose residues (ulvobiose U3s) carrying monomeric D-glucuronic acid or D-glucuronic acid-3-sulphate on O-2 of some L-rhamnose-3-sulphate units as the side chains. The SPS-CF exhibited significant in vitro anti-coagulant activity by which the activated partial thromboplastin time (aPTT) and thrombin time (TT) were significantly prolonged. The results of this

  16. Structural role of Gly(193) in serine proteases: investigations of a G555E (GLY193 in chymotrypsin) mutant of blood coagulation factor XI.

    PubMed

    Schmidt, Amy E; Ogawa, Taketoshi; Gailani, David; Bajaj, S Paul

    2004-07-01

    In serine proteases, Gly(193) is highly conserved with few exceptions. A patient with inherited deficiency of the coagulation serine protease factor XI (FXI) was reported to be homozygous for a Gly(555) --> Glu substitution. Gly(555) in FXI corresponds to Gly(193) in chymotrypsin, which is the numbering system used subsequently. To investigate the abnormality in FXI(G193E), we expressed and purified recombinant FXIa(G193E), activated it to FXIa(G193E), and compared its activity to wild type-activated FXI (FXIa(WT)). FXIa(G193E) activated FIX with approximately 300-fold reduced k(cat) and similar K(m), and hydrolyzed synthetic substrate with approximately 10-fold reduced K(m) and modestly reduced k(cat). Binding of antithrombin and the amyloid beta-precursor protein Kunitz domain inhibitor (APPI) to FXIa(G193E) was impaired approximately 8000- and approximately 100000-fold, respectively. FXIa(G193E) inhibition by diisopropyl fluoro-phosphate was approximately 30-fold slower and affinity for p-aminobenzamidine (S1 site probe) was 6-fold weaker than for FXIa(WT). The rate of carbamylation of NH(2)-Ile(16), which forms a salt bridge with Asp(194) in active serine proteases, was 4-fold faster for FXIa(G193E). These data indicate that the unoccupied active site of FXIa(G193E) is incompletely formed, and the amide N of Glu(193) may not point toward the oxyanion hole. Inclusion of saturating amounts of p-aminobenzamidine resulted in comparable rates of carbamylation for FXIa(WT) and FXIa(G193E), suggesting that the occupied active site has near normal conformation. Thus, binding of small synthetic substrates or inhibitors provides sufficient energy to allow the amide N of Glu(193) to point correctly toward the oxyanion hole. Homology modeling also indicates that the inability of FXIa(G193E) to bind antithrombin/APPI or activate FIX is caused, in part, by impaired accessibility of the S2' site because of a steric clash with Glu(193). Such arguments will apply to other

  17. Airway tissue factor-dependent coagulation activity in response to sulfur mustard analog 2-chloroethyl ethyl sulfide

    PubMed Central

    Rancourt, Raymond C.; Veress, Livia A.; Guo, XiaoLing; Jones, Tara N.; Hendry-Hofer, Tara B.

    2012-01-01

    Acute lung injury is a principal cause of morbidity and mortality in response to mustard gas (SM) inhalation. Obstructive, fibrin-containing airway casts have recently been reported in a rat inhalation model employing the SM analog 2-chloroethyl ethyl sulfide (CEES). The present study was designed to identify the mechanism(s) causing activation of the coagulation cascade after CEES-induced airway injury. Here we report that CEES inhalation elevates tissue factor (TF) activity and numbers of detached epithelial cells present in lavage fluid (BALF) from rats after exposure (18 h). In vitro studies using 16HBE cells, or with rat BALF, indicated that detached epithelial cells could convert factor X (FX) to the active form FXa when incubated with factor VII and could elicit rapid clotting of plasma. In addition, immunocytochemical analysis demonstrated elevated cell surface (TF) expression on CEES-exposed 16HBE cells as a function of time. However, total cell TF expression did not increase. Since membrane surfaces bearing TF are important determinants of clot initiation, anticoagulants directed against these entities were tested for ability to limit plasma clotting or FX activation capacity of BALF or culture media. Addition of tifacogin, a TF pathway inhibitor, effectively blocked either activity, demonstrating that the procoagulant actions of CEES were TF pathway dependent. Lactadherin, a protein capable of competing with clotting factors for phospholipid-binding sites, was partially effective in limiting these procoagulant actions. These findings indicate that TF pathway inhibition could be an effective strategy to prevent airway obstruction after SM or CEES inhalation. PMID:21964405

  18. [Blood coagulation disorders in children].

    PubMed

    Kurnik, K

    2008-12-01

    As in adults, haemorrhagic or thrombotic events may also occur in children. The underlying reasons are inborn or acquired. Inherited disorders usually present during in early infancy. In order to interpret clinical and laboratory findings in children, it is necessary to keep in mind some specific paediatric features. This knowledge also forms the basic requirement to choose the appropriate therapy.

  19. Coagulation Changes During Graded Orhostatic Stress and Recovery

    NASA Astrophysics Data System (ADS)

    Goswami, Nandu; Cvirn, Gerhard; Schlagenhauf, Aaxel; Leschnik, Bettina; Koestenberger, Martin; Roessler, Andreas; Jantscher, Andreas; Waha, James Elvis; Wolf, Sabine; Vrecko, Karoline; Juergens, Guenther; Hinghofer-Szalkay, Helmut

    2013-02-01

    Background: Orthostatic stress has been introduced as a novel paradigm for activating the coagulation system. We examined whether graded orthostatic stress (using head up tilt, HUT + lower body negative pressure, LBNP) until presyncope leads to anti / pro-coagulatory changes and how rapidly they return to baseline during recovery. Methodology: Eight male subjects were enrolled in this study. Presyncopal runs were carried out using HUT + LBNP. At minute zero, the tilt table was brought from 0° (supine) to 70 ° head-up position for 4 min, after which pressure in the LBNP chamber was reduced to -15, -30, and -45 mm Hg every 4 min. At presyncope, the subjects were returned to supine position. Coagulatory responses and plasma mass density (for volume changes) were measured before, during and 20 min after the orthostatic stress. Whole blood coagulation was examined by means of thrombelastometry. Platelet aggregation in whole blood was examined by using impedance aggregometry. Thrombin generation parameters, prothrombin levels, and markers of endothelial activation were measured in plasma samples. Results: At presyncope, plasma volume was 20 % below the initial supine value. Blood cell counts, prothrombin levels, thrombin peak, endogenous thrombin potential (ETP), and tissue factor pathway inhibitor (TFPI) levels increased during the protocol, commensurate with hemoconcentration. The markers of endothelial activation (tissue factor, TF, tissue plasminogen activator, t-PA) and the markers of thrombin generation (Prothrombin fragments 1 and 2, F1+2, and thrombin-antithrombin complex, TAT) increased significantly. During recovery, all the coagulation parameters returned to initial supine values except F1 +2 and TAT. Conclusion: Head-up tilt/LBNP leads to activation of the coagulation system. Some of the markers of thrombin formation are still at higher than supine levels during recovery.

  20. Activation and Coagulation Biomarkers are Independent Predictors for the Development of Opportunistic Disease in Patients with HIV Infection

    PubMed Central

    Rodger, Alison J; Fox, Zoe; Lundgren, Jens D; Kuller, Lew; Boesecke, Christoph; Gey, Daniela; Skoutelis, Athanassios; Goetz, Matthew Bidwell; Phillips, Andrew N

    2010-01-01

    Background Activation and coagulation biomarkers were measured within the SMART trial. Their associations with opportunistic disease (OD) in HIV-positive patients were examined. Methods Inflammatory (high-sensitivity C-reactive protein [hsCRP], interleukin-6 [IL-6], amyloid-A, and amyloid-P) and coagulation (D-dimer and prothrombin-fragment 1+2) markers were determined. Conditional logistic regression analyses were used to assess associations between these biomarkers and risk of OD. Results The 91 patients who developed an OD were matched to 182 controls. Patients with hsCRP≥5 μg/mL at baseline had a 3.5 (95%CI: 1.5-8.1) higher odds of OD versus those with hsCRP<1 μg/ml, Ptrend=0.003, and patients with IL-6≥3 pg/mL at baseline had a 2.4 (95%CI: 1.0-5.4) higher odds of OD versus those with IL-6<1.5 pg/mL, Ptrend=0.02. No other baseline biomarkers predicted development of an OD. Latest hsCRP (OR: 7.6 (95%CI: 2.0-28.5) for those with hsCRP≥5 μg/mL versus hsCRP<1 μg/mL, Ptrend=0.002), latest amyloid-A (OR: 3.8 (95%CI: 1.1-13.4) for those with amyloid-A ≥6 mg/L versus amyloid-A <2 mg/L, Ptrend=0.03) and latest IL-6 (OR 2.4 (95%CI: 0.7-8.8) for those with IL-6≥3 pg/mL versus IL-6<1.5 pg/mL, Ptrend=0.04) were also associated with developing an OD. Conclusions Higher IL-6 and hsCRP independently predicted development of OD. These biomarkers could provide additional prognostic information for predicting risk of OD. PMID:19678756

  1. A loop of coagulation factor VIIa influencing macromolecular substrate specificity.

    PubMed

    Bjelke, Jais R; Persson, Egon; Rasmussen, Hanne B; Kragelund, Birthe B; Olsen, Ole H

    2007-01-01

    Coagulation factor VIIa (FVIIa) belongs to a family of proteases being part of the stepwise, self-amplifying blood coagulation cascade. To investigate the impact of the mutation Met(298{156})Lys in FVIIa, we replaced the Gly(283{140})-Met(298{156}) loop with the corresponding loop of factor Xa. The resulting variant exhibited increased intrinsic activity, concurrent with maturation of the active site, a less accessible N-terminus, and, interestingly, an altered macromolecular substrate specificity reflected in an increased ability to cleave factor IX (FIX) and a decreased rate of FX activation compared to that of wild-type FVIIa. In complex with tissue factor, activation of FIX, but not of FX, returned to normal. Deconvolution of the loop graft in order to identify important side chain substitutions resulted in the mutant Val(158{21})Asp/Leu(287{144})Thr/Ala(294{152})Ser/Glu(296{154}) Ile/Met(298{156})Lys-FVIIa with almost the same activity and specificity profile. We conclude that a lysine residue in position 298{156} of FVIIa requires a hydrophilic environment to be fully accommodated. This position appears critical for substrate specificity among the proteases of the blood coagulation cascade due to its prominent position in the macromolecular exosite and possibly via its interaction with the corresponding position in the substrate (i.e. FIX or FX). PMID:17182039

  2. Removal of Trace Pharmaceuticals from Water using coagulation and powdered activated carbon as pretreatment to ultrafiltration membrane system.

    PubMed

    Sheng, Chenguang; Nnanna, A G Agwu; Liu, Yanghe; Vargo, John D

    2016-04-15

    In this study, the efficacy of water treatment technologies: ultra-filtration (UF), powdered activated carbon (PAC), coagulation (COA) and a combination of these technologies (PAC/UF and COA/UF) to remove target pharmaceuticals (Acetaminophen, Bezafibrate, Caffeine, Carbamazepine, Cotinine, Diclofenac, Gemfibrozil, Ibuprofen, Metoprolol, Naproxen, Sulfadimethoxine, Sulfamethazine, Sulfamethoxazole, Sulfathiazole, Triclosan and Trimethoprim) was investigated. Samples of wastewater from municipal WWTPs were analyzed using direct aqueous injection High Performance Liquid Chromatography with Tandem Quadrupole Mass Spectrometric (LC/MS/MS) detection. On concentration basis, results showed an average removal efficiency of 29%, 50%, and 7%, respectively, for the UF, PAC dosage of 50ppm, and COA dosage of 10ppm. When PAC dosage of 100ppm was used as pretreatment to the combined PAC and UF in-line membrane system, a 90.3% removal efficiency was achieved. The removal efficiency of UF in tandem with COA was 33%, an increase of 4% compared with the single UF treatment. The adsorption effect of PAC combined with the physical separation process of UF revealed the best treatment strategy for removing pharmaceutical contaminant from water. PMID:26867086

  3. Fibrinogen Vicenza and Genova II: two new cases of congenital dysfibrinogenemia with isolated defect of fibrin monomer polymerization and inhibitory activity on normal coagulation.

    PubMed

    Rodeghiero, F; Castaman, G C; Dal Belin Peruffo, A; Dini, E; Galletti, A; Barone, E; Gastaldi, G

    1987-06-01

    Two new cases of congenital dysfibrinogenemia are presented in which defective fibrin monomer polymerization and inhibitory activity on normal coagulation were observed. They have been tentatively called fibrinogen Vicenza and Genova II. The first was discovered in a family with mild bleeding diathesis, the second in an asymptomatic family. In almost all reported cases of fibrinogens with defective fibrin monomer polymerization, additional functional or structural defects have been detected. In our cases, on the contrary, detailed investigations failed to show any other abnormality. Fibrinogen Genova II is apparently identical to fibrinogen Baltimore IV, whereas fibrinogen Vicenza is similar to fibrinogen Troyes and Genova I, but also exerts an evident inhibitory activity on normal coagulation and differs from fibrinogen Genova II and Baltimore IV showing a different kinetic pattern of fibrin monomer polymerization.

  4. Depinning as a coagulation process

    NASA Astrophysics Data System (ADS)

    İşeri, M.; Kaspar, D.; Mungan, M.

    2016-08-01

    We consider a one-dimensional model that describes the depinning of an elastic string of particles in a strongly pinning, phase-disordered periodic environment under a slowly increasing force. The evolution towards depinning occurs by the triggering of avalanches in regions of activity which are at first isolated, but later grow and merge. For large system sizes the dynamically critical behavior is dominated by the coagulation of these active regions. Our analysis and numerical simulations show that the evolution of the sizes of active regions is well described by a Smoluchowski coagulation equation, allowing us to predict correlation lengths and avalanche sizes in terms of certain moments of the size distribution.

  5. Fibrinopeptide A blood test

    MedlinePlus

    ... problems with blood clotting such as disseminated intravascular coagulation ( DIC ). Certain types of leukemia are associated with ... be a sign of: Cellulitis DIC (disseminated intravascular coagulation) Leukemia at the time of diagnosis, during early ...

  6. MASP-3 is the exclusive pro-factor D activator in resting blood: the lectin and the alternative complement pathways are fundamentally linked

    PubMed Central

    Dobó, József; Szakács, Dávid; Oroszlán, Gábor; Kortvely, Elod; Kiss, Bence; Boros, Eszter; Szász, Róbert; Závodszky, Péter; Gál, Péter; Pál, Gábor

    2016-01-01

    MASP-3 was discovered 15 years ago as the third mannan-binding lectin (MBL)-associated serine protease of the complement lectin pathway. Lacking any verified substrate its role remained ambiguous. MASP-3 was shown to compete with a key lectin pathway enzyme MASP-2 for MBL binding, and was therefore considered to be a negative complement regulator. Later, knock-out mice experiments suggested that MASP-1 and/or MASP-3 play important roles in complement pro-factor D (pro-FD) maturation. However, studies on a MASP-1/MASP-3-deficient human patient produced contradicting results. In normal resting blood unperturbed by ongoing coagulation or complement activation, factor D is present predominantly in its active form, suggesting that resting blood contains at least one pro-FD activating proteinase that is not a direct initiator of coagulation or complement activation. We have recently showed that all three MASPs can activate pro-FD in vitro. In resting blood, however, using our previously evolved MASP-1 and MASP-2 inhibitors we proved that neither MASP-1 nor MASP-2 activates pro-FD. Other plasma proteinases, particularly MASP-3, remained candidates for that function. For this study we evolved a specific MASP-3 inhibitor and unambiguously proved that activated MASP-3 is the exclusive pro-FD activator in resting blood, which demonstrates a fundamental link between the lectin and alternative pathways. PMID:27535802

  7. MASP-3 is the exclusive pro-factor D activator in resting blood: the lectin and the alternative complement pathways are fundamentally linked.

    PubMed

    Dobó, József; Szakács, Dávid; Oroszlán, Gábor; Kortvely, Elod; Kiss, Bence; Boros, Eszter; Szász, Róbert; Závodszky, Péter; Gál, Péter; Pál, Gábor

    2016-01-01

    MASP-3 was discovered 15 years ago as the third mannan-binding lectin (MBL)-associated serine protease of the complement lectin pathway. Lacking any verified substrate its role remained ambiguous. MASP-3 was shown to compete with a key lectin pathway enzyme MASP-2 for MBL binding, and was therefore considered to be a negative complement regulator. Later, knock-out mice experiments suggested that MASP-1 and/or MASP-3 play important roles in complement pro-factor D (pro-FD) maturation. However, studies on a MASP-1/MASP-3-deficient human patient produced contradicting results. In normal resting blood unperturbed by ongoing coagulation or complement activation, factor D is present predominantly in its active form, suggesting that resting blood contains at least one pro-FD activating proteinase that is not a direct initiator of coagulation or complement activation. We have recently showed that all three MASPs can activate pro-FD in vitro. In resting blood, however, using our previously evolved MASP-1 and MASP-2 inhibitors we proved that neither MASP-1 nor MASP-2 activates pro-FD. Other plasma proteinases, particularly MASP-3, remained candidates for that function. For this study we evolved a specific MASP-3 inhibitor and unambiguously proved that activated MASP-3 is the exclusive pro-FD activator in resting blood, which demonstrates a fundamental link between the lectin and alternative pathways.

  8. MASP-3 is the exclusive pro-factor D activator in resting blood: the lectin and the alternative complement pathways are fundamentally linked.

    PubMed

    Dobó, József; Szakács, Dávid; Oroszlán, Gábor; Kortvely, Elod; Kiss, Bence; Boros, Eszter; Szász, Róbert; Závodszky, Péter; Gál, Péter; Pál, Gábor

    2016-01-01

    MASP-3 was discovered 15 years ago as the third mannan-binding lectin (MBL)-associated serine protease of the complement lectin pathway. Lacking any verified substrate its role remained ambiguous. MASP-3 was shown to compete with a key lectin pathway enzyme MASP-2 for MBL binding, and was therefore considered to be a negative complement regulator. Later, knock-out mice experiments suggested that MASP-1 and/or MASP-3 play important roles in complement pro-factor D (pro-FD) maturation. However, studies on a MASP-1/MASP-3-deficient human patient produced contradicting results. In normal resting blood unperturbed by ongoing coagulation or complement activation, factor D is present predominantly in its active form, suggesting that resting blood contains at least one pro-FD activating proteinase that is not a direct initiator of coagulation or complement activation. We have recently showed that all three MASPs can activate pro-FD in vitro. In resting blood, however, using our previously evolved MASP-1 and MASP-2 inhibitors we proved that neither MASP-1 nor MASP-2 activates pro-FD. Other plasma proteinases, particularly MASP-3, remained candidates for that function. For this study we evolved a specific MASP-3 inhibitor and unambiguously proved that activated MASP-3 is the exclusive pro-FD activator in resting blood, which demonstrates a fundamental link between the lectin and alternative pathways. PMID:27535802

  9. Structural characterization of coagulant Moringa oleifera Lectin and its effect on hemostatic parameters.

    PubMed

    Luz, Luciana de Andrade; Silva, Mariana Cristina Cabral; Ferreira, Rodrigo da Silva; Santana, Lucimeire Aparecida; Silva-Lucca, Rosemeire Aparecida; Mentele, Reinhard; Oliva, Maria Luiza Vilela; Paiva, Patricia Maria Guedes; Coelho, Luana Cassandra Breitenbach Barroso

    2013-07-01

    Lectins are carbohydrate recognition proteins. cMoL, a coagulant Moringa oleifera Lectin, was isolated from seeds of the plant. Structural studies revealed a heat-stable and pH resistant protein with 101 amino acids, 11.67 theoretical pI and 81% similarity with a M. oleifera flocculent protein. Secondary structure content was estimated as 46% α-helix, 12% β-sheets, 17% β-turns and 25% unordered structures belonging to the α/β tertiary structure class. cMoL significantly prolonged the time required for blood coagulation, activated partial thromboplastin (aPTT) and prothrombin times (PT), but was not so effective in prolonging aPTT in asialofetuin presence. cMoL acted as an anticoagulant protein on in vitro blood coagulation parameters and at least on aPTT, the lectin interacted through the carbohydrate recognition domain. PMID:23537800

  10. Clinical and prognostic significance of coagulation assays in lung cancer.

    PubMed

    Tas, Faruk; Kilic, Leyla; Serilmez, Murat; Keskin, Serkan; Sen, Fatma; Duranyildiz, Derya

    2013-03-01

    Activation of coagulation and fibrinolysis is frequently encountered among cancer patients. Such tumors are supposed to be associated with higher risk of invasion, metastases and eventually worse outcome. The aim of this study is to explore the prognostic value of blood coagulation tests for lung cancer patients. The study comprised 110 lung cancer patients. Pretreatment blood coagulation tests including PT, aPTT, PTA, INR, D-dimer, fibrinogen levels and platelet counts were evaluated. The plasma level of all coagulation tests revealed statistically significant difference between patient and control group (p < 0.001). There was a significant association between D-Dimer levels and histological subtypes of NSCLC, pointing an elevated plasma D-dimer level in squamous cell cancer (p = 0.035). Patients with extensive stage SCLC exhibited evidently higher levels of D-Dimer, INR and PLT (p = 0.037, p = 0.042, p = 0.04, respectively). Prolongation of PT and INR had statistically significant adverse effect on survival (p = 0.05 and p = 0.014, respectively). Although prolonged aPTT and high levels of D-dimer was associated with worse survival, the difference was not statistically significant (p = 0.117, p = 0.104). Multivariate analysis revealed INR as the sole independent prognostic variable among coagulation parameters (p = 0.05). In conclusion, elevation of PT and INR are associated with decreased survival in lung cancer patients.

  11. Coagulation fibrinolysis in sickle-cell disease

    PubMed Central

    Gordon, P. A.; Breeze, G. R.; Mann, J. R.; Stuart, J.

    1974-01-01

    A study of fibrinolytic activity in sickle-cell patients during asymptomatic periods has shown a normal fibrinolytic response to exercise and local heat to the arm. During vasoocclusive crises there was no significant decrease in fibrinolytic activity. These results contrast with earlier reports of decreased fibrinolysis during crisis and a suggestion that fibrinolytic activators might be of value in preventing vasoocclusive episodes. Patients in painful crisis showed a significant rise in fibrinogen concentration and fall in platelet count. The former may contribute to localized vascular sludging by increasing whole-blood viscosity, while the latter probably results from local trapping of platelets in areas of sickling or from subsequent splenic sequestration of damaged platelets. There was no evidence of disseminated, as opposed to localized, intravascular coagulation during crisis. PMID:4412492

  12. Optimizing the industrial wastewater pretreatment by activated carbon and coagulation: effects of hydrophobicity/hydrophilicity and molecular weights of dissolved organics.

    PubMed

    Khan, M Hammad; Ha, Dong-Hwan; Jung, Jinyoung

    2013-01-01

    This study addresses industrial wastewater treatment to remove dissolved organic compounds (DOC) using Fenton and coagulation processes, followed by granular activated carbon (GAC), and powdered activated carbon (PAC) as a pretreatment before reverse osmosis (RO). The effects of the hydrophobic / hydrophilic fractions and the molecular weights (MW) of the organics on DOC removal were tested and used to optimize the combination process. The raw wastewater (RWW) had a dominant hydrophobic fraction, as determined by polymeric resins Amberlite XAD-4. High performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) results showed that MW of organics were 256, 172, 258, 146, 392, 321, 182, 373, 276, 365, 409 and 453 in increasing order of hydrophobicity. GAC had higher adsorption capacity and was more selective for hydrophobic DOC removal than PAC. The removal efficiency of DOC by PAC and GAC was decreased after Fenton treatment, which decreased the hydrophobic fraction. Coagulation with ferric chloride efficiently removed the non-ionic hydrophilic and anionic hydrophilic organics. The coagulant doses selected as a pretreatment before GAC were 2.1 and 15.5 mg Fe(III)/mg DOC. The effluent total organic carbon (TOC) trends were correlated with the hydrophobic and hydrophilic fractions by using a rapid small-scale column test (RSSCT) for GAC breakthrough with a scale down factor of 5. GAC preferentially adsorbed the hydrophobic and the cationic hydrophilic organics. The effluent TOC trend could be divided into four stages: maximum adsorption, hydrophobic stage, exhaustion, and biological. The TOC removal after the exhaustion stage was almost equal to the hydrophilic fraction of TOC. Therefore these results demonstrated that the combination of coagulation and GAC adsorption was a highly efficient process for reducing DOC.

  13. Evaluation of cytotoxicity and inflammatory activity of wastewater collected from a textile factory before and after treatment by coagulation-flocculation methods.

    PubMed

    Makene, Vedastus W; Tijani, Jimoh O; Petrik, Leslie F; Pool, Edmund J

    2016-08-01

    Effective treatment of textile effluent prior to discharge is necessary in order to avert the associated adverse health impacts on human and aquatic life. In the present investigation, coagulation/flocculation processes were evaluated for the effectiveness of the individual treatment. Effectiveness of the treatment was evaluated based on the physicochemical characteristics. The quality of the pre-treated and post-flocculation treated effluent was further evaluated by determination of cytotoxicity and inflammatory activity using RAW264.7 cell cultures. Cytotoxicity was determined using WST-1 assay. Nitric oxide (NO) and interleukin 6 (IL-6) were used as biomarkers of inflammation. NO was determined in cell culture supernatant using the Griess reaction assay. The IL-6 secretion was determined using double antibody sandwich enzyme linked immunoassay (DAS ELISA). Cytotoxicity results show that raw effluent reduced the cell viability significantly (P < 0.001) compared to the negative control. All effluent samples treated by coagulation/flocculation processes at 1 in 100 dilutions had no cytotoxic effects on RAW264.7 cells. The results on inflammatory activities show that the raw effluent and effluent treated with 1.6 g/L of Fe-Mn oxide induced significantly (P < 0.001) higher NO production than the negative control. The inflammatory results further show that the raw effluent induced significantly (P < 0.001) higher production of IL-6 than the negative control. Among the coagulants/flocculants evaluated Al2(SO4)3.14H2O at a dosage of 1.6 g/L was the most effective to remove both toxic and inflammatory pollutants. In conclusion, the inflammatory responses in RAW264.7 cells can be used as sensitive biomarkers for monitoring the effectiveness of coagulation/flocculation processes used for textile effluent treatment.

  14. Optimizing the industrial wastewater pretreatment by activated carbon and coagulation: effects of hydrophobicity/hydrophilicity and molecular weights of dissolved organics.

    PubMed

    Khan, M Hammad; Ha, Dong-Hwan; Jung, Jinyoung

    2013-01-01

    This study addresses industrial wastewater treatment to remove dissolved organic compounds (DOC) using Fenton and coagulation processes, followed by granular activated carbon (GAC), and powdered activated carbon (PAC) as a pretreatment before reverse osmosis (RO). The effects of the hydrophobic / hydrophilic fractions and the molecular weights (MW) of the organics on DOC removal were tested and used to optimize the combination process. The raw wastewater (RWW) had a dominant hydrophobic fraction, as determined by polymeric resins Amberlite XAD-4. High performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) results showed that MW of organics were 256, 172, 258, 146, 392, 321, 182, 373, 276, 365, 409 and 453 in increasing order of hydrophobicity. GAC had higher adsorption capacity and was more selective for hydrophobic DOC removal than PAC. The removal efficiency of DOC by PAC and GAC was decreased after Fenton treatment, which decreased the hydrophobic fraction. Coagulation with ferric chloride efficiently removed the non-ionic hydrophilic and anionic hydrophilic organics. The coagulant doses selected as a pretreatment before GAC were 2.1 and 15.5 mg Fe(III)/mg DOC. The effluent total organic carbon (TOC) trends were correlated with the hydrophobic and hydrophilic fractions by using a rapid small-scale column test (RSSCT) for GAC breakthrough with a scale down factor of 5. GAC preferentially adsorbed the hydrophobic and the cationic hydrophilic organics. The effluent TOC trend could be divided into four stages: maximum adsorption, hydrophobic stage, exhaustion, and biological. The TOC removal after the exhaustion stage was almost equal to the hydrophilic fraction of TOC. Therefore these results demonstrated that the combination of coagulation and GAC adsorption was a highly efficient process for reducing DOC. PMID:23383639

  15. Evaluation of cytotoxicity and inflammatory activity of wastewater collected from a textile factory before and after treatment by coagulation-flocculation methods.

    PubMed

    Makene, Vedastus W; Tijani, Jimoh O; Petrik, Leslie F; Pool, Edmund J

    2016-08-01

    Effective treatment of textile effluent prior to discharge is necessary in order to avert the associated adverse health impacts on human and aquatic life. In the present investigation, coagulation/flocculation processes were evaluated for the effectiveness of the individual treatment. Effectiveness of the treatment was evaluated based on the physicochemical characteristics. The quality of the pre-treated and post-flocculation treated effluent was further evaluated by determination of cytotoxicity and inflammatory activity using RAW264.7 cell cultures. Cytotoxicity was determined using WST-1 assay. Nitric oxide (NO) and interleukin 6 (IL-6) were used as biomarkers of inflammation. NO was determined in cell culture supernatant using the Griess reaction assay. The IL-6 secretion was determined using double antibody sandwich enzyme linked immunoassay (DAS ELISA). Cytotoxicity results show that raw effluent reduced the cell viability significantly (P < 0.001) compared to the negative control. All effluent samples treated by coagulation/flocculation processes at 1 in 100 dilutions had no cytotoxic effects on RAW264.7 cells. The results on inflammatory activities show that the raw effluent and effluent treated with 1.6 g/L of Fe-Mn oxide induced significantly (P < 0.001) higher NO production than the negative control. The inflammatory results further show that the raw effluent induced significantly (P < 0.001) higher production of IL-6 than the negative control. Among the coagulants/flocculants evaluated Al2(SO4)3.14H2O at a dosage of 1.6 g/L was the most effective to remove both toxic and inflammatory pollutants. In conclusion, the inflammatory responses in RAW264.7 cells can be used as sensitive biomarkers for monitoring the effectiveness of coagulation/flocculation processes used for textile effluent treatment. PMID:27418078

  16. Inhibition of coagulation, fibrinolysis, and endothelial cell activation by a p38 mitogen-activated protein kinase inhibitor during human endotoxemia.

    PubMed

    Branger, Judith; van den Blink, Bernt; Weijer, Sebastiaan; Gupta, Abhya; van Deventer, Sander J H; Hack, C Erik; Peppelenbosch, Maikel P; van der Poll, Tom

    2003-06-01

    P38 mitogen-activated protein kinase (MAPK) is an important component of intracellular signaling cascades that initiate various inflammatory cellular responses. To determine the role of p38 MAPK in the procoagulant response to lipopolysaccharide (LPS), 24 healthy subjects were exposed to an intravenous dose of LPS (4 ng/kg), preceded 3 hours earlier by orally administered 600 or 50 mg BIRB 796 BS (a specific p38 MAPK inhibitor), or placebo. The 600-mg dose of BIRB 796 BS strongly inhibited LPS-induced coagulation activation, as measured by plasma concentrations of the prothrombin fragment F1 + 2. BIRB 796 BS also dose dependently attenuated the activation and subsequent inhibition of the fibrinolytic system (plasma tissue-type plasminogen activator, plasmin-alpha2-antiplasmin complexes, and plasminogen activator inhibitor type 1) and endothelial cell activation (plasma soluble E-selectin and von Willebrand factor). Activation of p38 MAPK plays an important role in the procoagulant and endothelial cell response after in vivo exposure to LPS.

  17. Ontogenetic variation of metalloproteinases and plasma coagulant activity in venoms of wild Bothrops atrox specimens from Amazonian rain forest.

    PubMed

    López-Lozano, Jorge Luis; de Sousa, Marcelo Valle; Ricart, Carlos André O; Chávez-Olortegui, Carlos; Flores Sanchez, Eladio; Muniz, Emiro G; Bührnheim, Paulo F; Morhy, Lauro

    2002-07-01

    A comparative study of venoms from juvenile, sub-adult and adult wild Bothrops atrox specimens captured in Manaus region (Brazil) was performed. All venoms tested had acidic pH (5.5) and the human plasma coagulant activity was higher in venoms from juvenile and sub-adult specimens than in adults. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the most intense bands in adult venoms corresponded to polypeptides of 23 and 50kDa. The 23kDa protein was not detected in juvenile venoms. The 23 and 50kDa proteins were purified by two steps of reversed phase-HPLC followed by size exclusion HPLC. Partial amino acid sequence of the 23kDa protein showed homology to metalloproteinases from other snake venoms. Electrospray ionization mass spectrometric analysis (ESI-MS) showed that the 23kDa band contained at least three isoforms of 23030, 23300 and 23645Da. The 50kDa polypeptide was N-terminally blocked for Edman degradation and presented molecular masses ranging from 46.8 to 49.4kDa by ESI-MS. Both proteins were detected by anti-mutalysin II antibodies in immunoblotting assay indicating that they belong to the metalloproteinase family. Immunoblotting analysis also showed that the 23kDa band increased in intensity from juvenile to adult specimens.SDS-PAGE analysis of juvenile and adult venoms following autoproteolysis in pH 7.4 suggested that endogenous venom metalloproteinases can digest the 50kDa metalloproteinase, originating a new protein band of 27kDa. It was also demonstrated in juvenile venoms that the 23kDa band was not the result of proteolytic processing of the 50kDa metalloproteinase. PMID:12076654

  18. Ontogenetic variation of metalloproteinases and plasma coagulant activity in venoms of wild Bothrops atrox specimens from Amazonian rain forest.

    PubMed

    López-Lozano, Jorge Luis; de Sousa, Marcelo Valle; Ricart, Carlos André O; Chávez-Olortegui, Carlos; Flores Sanchez, Eladio; Muniz, Emiro G; Bührnheim, Paulo F; Morhy, Lauro

    2002-07-01

    A comparative study of venoms from juvenile, sub-adult and adult wild Bothrops atrox specimens captured in Manaus region (Brazil) was performed. All venoms tested had acidic pH (5.5) and the human plasma coagulant activity was higher in venoms from juvenile and sub-adult specimens than in adults. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the most intense bands in adult venoms corresponded to polypeptides of 23 and 50kDa. The 23kDa protein was not detected in juvenile venoms. The 23 and 50kDa proteins were purified by two steps of reversed phase-HPLC followed by size exclusion HPLC. Partial amino acid sequence of the 23kDa protein showed homology to metalloproteinases from other snake venoms. Electrospray ionization mass spectrometric analysis (ESI-MS) showed that the 23kDa band contained at least three isoforms of 23030, 23300 and 23645Da. The 50kDa polypeptide was N-terminally blocked for Edman degradation and presented molecular masses ranging from 46.8 to 49.4kDa by ESI-MS. Both proteins were detected by anti-mutalysin II antibodies in immunoblotting assay indicating that they belong to the metalloproteinase family. Immunoblotting analysis also showed that the 23kDa band increased in intensity from juvenile to adult specimens.SDS-PAGE analysis of juvenile and adult venoms following autoproteolysis in pH 7.4 suggested that endogenous venom metalloproteinases can digest the 50kDa metalloproteinase, originating a new protein band of 27kDa. It was also demonstrated in juvenile venoms that the 23kDa band was not the result of proteolytic processing of the 50kDa metalloproteinase.

  19. The dirty side of the intrinsic pathway of coagulation.

    PubMed

    Cooley, Brian C

    2016-09-01

    Whereas the extrinsic pathway of coagulation seals off bleeding at the cut tissue edges, it is proposed that the intrinsic pathway exploits the dirt from the skin surface to generate an outer coagulum of the oozing blood. Activated Factor XII (FXIIa) in this outer cap generates Factor XIa, which triggers clotting, and kallikrein that feeds back to form more FXIIa to promote the process. This dirty-wound hypothesis of coagulation function by the intrinsic pathway is supported by the use of dirt-based compounds in activated partial thromboplastin time assays as well as the evolutionary record where marine life that do not have skin-adherent dirt lack Factor XII, including marine mammals that have returned to sea life. PMID:27373598

  20. Indolic uremic solutes enhance procoagulant activity of red blood cells through phosphatidylserine exposure and microparticle release.

    PubMed

    Gao, Chunyan; Ji, Shuting; Dong, Weijun; Qi, Yushan; Song, Wen; Cui, Debin; Shi, Jialan

    2015-11-01

    Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs), the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS) and indole-3-acetic acid (IAA) on procoagulant activity (PCA) of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients). Phosphatidylserine (PS) exposure of RBCs and their microparticles (MPs) release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca(2+) ([Ca(2+)]) with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca(2+)]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process. PMID:26516916

  1. Platelets and coagulation in infection

    PubMed Central

    Davis, Rachelle P; Miller-Dorey, Sarah; Jenne, Craig N

    2016-01-01

    Disseminated intravascular coagulation (DIC) is a frequent complication in sepsis that is associated with worse outcomes and higher mortality in patients. In addition to the uncontrolled generation of thrombi throughout the patient's vasculature, DIC often consumes large quantities of clotting factors leaving the patient susceptible to hemorrhaging. Owing to these complications, patients often receive anticoagulants to treat the uncontrolled clotting, often with mixed outcomes. This lack of success with the current array of anticoagulants can be partly explained by the fact that during sepsis clotting is often initiated by the immune system. Systemic inflammation has the capacity to activate and amplify coagulation and, as such, potential therapies for the treatment of sepsis-associated DIC need to address the interaction between inflammation and coagulation. Recent studies have suggested that platelets and neutrophil extracellular traps (NETs) are the key mediators of infection-induced coagulation. This review explores current anticoagulant therapies and discusses the development of future therapies to target platelet and NET-mediated coagulation. PMID:27525062

  2. Breaking boundaries—coagulation and fibrinolysis at the neurovascular interface

    PubMed Central

    Bardehle, Sophia; Rafalski, Victoria A.; Akassoglou, Katerina

    2015-01-01

    Blood proteins at the neurovascular unit (NVU) are emerging as important molecular determinants of communication between the brain and the immune system. Over the past two decades, roles for the plasminogen activation (PA)/plasmin system in fibrinolysis have been extended from peripheral dissolution of blood clots to the regulation of central nervous system (CNS) functions in physiology and disease. In this review, we discuss how fibrin and its proteolytic degradation affect neuroinflammatory, degenerative and repair processes. In particular, we focus on novel functions of fibrin—the final product of the coagulation cascade and the main substrate of plasmin—in the activation of immune responses and trafficking of immune cells into the brain. We also comment on the suitability of the coagulation and fibrinolytic systems as potential biomarkers and drug targets in diseases, such as multiple sclerosis (MS), Alzheimer’s disease (AD) and stroke. Studying coagulation and fibrinolysis as major molecular pathways that regulate cellular functions at the NVU has the potential to lead to the development of novel strategies for the detection and treatment of neurologic diseases. PMID:26441525

  3. Pretreatment with β-Boswellic Acid Improves Blood Stasis Induced Endothelial Dysfunction: Role of eNOS Activation.

    PubMed

    Wang, Mingming; Chen, Minchun; Ding, Yi; Zhu, Zhihui; Zhang, Yikai; Wei, Peifeng; Wang, Jingwen; Qiao, Yi; Li, Liang; Li, Yuwen; Wen, Aidong

    2015-01-01

    Vascular endothelial cells play an important role in modulating anti-thrombus and maintaining the natural function of vascular by secreting many active substances. β-boswellic acid (β-BA) is an active triterpenoid compound from the extract of boswellia serrate. In this study, it is demonstrated that β-BA ameliorates plasma coagulation parameters, protects endothelium from blood stasis induced injury and prevents blood stasis induced impairment of endothelium-dependent vasodilatation. Moreover, it is found that β-BA significantly increases nitric oxide (NO) and cyclic guanosine 3', 5'-monophosphate (cGMP) levels in carotid aortas of blood stasis rats. To stimulate blood stasis-like conditions in vitro, human umbilical vein endothelial cells (HUVECs) were exposed to transient oxygen and glucose deprivation (OGD). Treatment of β-BA significantly increased intracellular NO level. Western blot and immunofluorescence as well as immunohistochemistry reveal that β-BA increases phosphorylation of enzyme nitric oxide synthase (eNOS) at Ser1177. In addition, β-BA mediated endothelium-dependent vasodilatation can be markedly blocked by eNOS inhibitor L-NAME in blood stasis rats. In OGD treated HUEVCs, the protective effect of β-BA is attenuated by knockdown of eNOS. In conclusion, the above findings provide convincing evidence for the protective effects of β-BA on blood stasis induced endothelial dysfunction by eNOS signaling pathway. PMID:26482008

  4. Pretreatment with β-Boswellic Acid Improves Blood Stasis Induced Endothelial Dysfunction: Role of eNOS Activation

    PubMed Central

    Wang, Mingming; Chen, Minchun; Ding, Yi; Zhu, Zhihui; Zhang, Yikai; Wei, Peifeng; Wang, Jingwen; Qiao, Yi; Li, Liang; Li, Yuwen; Wen, Aidong

    2015-01