PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 2556813-0 1989 The relationship between anti-factor Xa level and clinical outcome in patients receiving enoxaparine low molecular weight heparin to prevent deep vein thrombosis after hip replacement. Heparin 122-129 coagulation factor X Homo sapiens 30-39 2613105-2 1989 Both FR-860 and UF-heparin dose-dependently prolonged the recalcification time, activated partial thromboplastin time, prothrombin time, factor Xa (F.Xa) clotting time and thrombin time. Heparin 19-26 coagulation factor X Homo sapiens 137-146 2558424-0 1989 Influence of a low molecular weight heparin on the inhibition of factor Xa and thrombin in hip surgery. Heparin 36-43 coagulation factor X Homo sapiens 65-74 2722856-1 1989 Heparin and heparin fragments in the molecular mass range 1,700-20,000 Da were examined for their ability to accelerate the antithrombin III (AT III)-dependent inhibition of human factor Xa and the prothrombin converting complex (prothrombinase) during human prothrombin activation. Heparin 0-7 coagulation factor X Homo sapiens 180-189 2529852-4 1989 Differences were also observed in the maximal acceleration of the antithrombin III-Factor Xa interaction: 1.2 x 10(9) M-1.min-1 at 0.2 microM-heparin sulphate compared with 2.2 x 10(9) M-1.min-1 at 0.04 microM-heparin. Heparin 142-149 coagulation factor X Homo sapiens 83-92 2529852-11 1989 The rate constant for transformation of the antithrombin III-Factor Xa complex into irreversible product differed between heparan sulphate (96 min-1) and heparin (429 min-1). Heparin 154-161 coagulation factor X Homo sapiens 61-70 2476115-15 1989 Among several derivatives of pentosan polysulphate or of heparin which were tested, those having the higher degree of sulphation and/or molecular mass were the most efficient in enhancing the rate of activation of protein C by factor Xa in the presence of phospholipids. Heparin 57-64 coagulation factor X Homo sapiens 227-236 2722856-1 1989 Heparin and heparin fragments in the molecular mass range 1,700-20,000 Da were examined for their ability to accelerate the antithrombin III (AT III)-dependent inhibition of human factor Xa and the prothrombin converting complex (prothrombinase) during human prothrombin activation. Heparin 12-19 coagulation factor X Homo sapiens 180-189 2722856-1 1989 Heparin and heparin fragments in the molecular mass range 1,700-20,000 Da were examined for their ability to accelerate the antithrombin III (AT III)-dependent inhibition of human factor Xa and the prothrombin converting complex (prothrombinase) during human prothrombin activation. Heparin 12-19 coagulation factor X Homo sapiens 230-244 2738078-5 1989 Bioactivity of the immobilized conjugate (heparin activity) was measured in terms of increased clotting times (thrombin time assay) and for the inactivation of Factor Xa. Heparin 42-49 coagulation factor X Homo sapiens 160-169 2722856-10 1989 243, 31-37), all the heparins showed a 5-fold higher rate of inhibition of factor Xa when compared with the inhibition of prothrombinase, indicating that the factor Va-mediated protection of factor Xa from inhibition by AT III/heparin is independent of the molecular size of the heparin. Heparin 21-29 coagulation factor X Homo sapiens 75-84 2722856-10 1989 243, 31-37), all the heparins showed a 5-fold higher rate of inhibition of factor Xa when compared with the inhibition of prothrombinase, indicating that the factor Va-mediated protection of factor Xa from inhibition by AT III/heparin is independent of the molecular size of the heparin. Heparin 21-29 coagulation factor X Homo sapiens 191-200 2722856-10 1989 243, 31-37), all the heparins showed a 5-fold higher rate of inhibition of factor Xa when compared with the inhibition of prothrombinase, indicating that the factor Va-mediated protection of factor Xa from inhibition by AT III/heparin is independent of the molecular size of the heparin. Heparin 21-28 coagulation factor X Homo sapiens 75-84 2722856-10 1989 243, 31-37), all the heparins showed a 5-fold higher rate of inhibition of factor Xa when compared with the inhibition of prothrombinase, indicating that the factor Va-mediated protection of factor Xa from inhibition by AT III/heparin is independent of the molecular size of the heparin. Heparin 21-28 coagulation factor X Homo sapiens 191-200 2722856-11 1989 Our original approach has also revealed a hitherto unrecognized phenomenon, namely, in addition to the accelerating effect of the heparins on the rate of formation of the inactive AT III-factor Xa complex, heparins with Mr greater than 4,500 reduce the initial rate of thrombin generation in the presence of AT III in a concentration-dependent way. Heparin 130-138 coagulation factor X Homo sapiens 187-196 2722856-11 1989 Our original approach has also revealed a hitherto unrecognized phenomenon, namely, in addition to the accelerating effect of the heparins on the rate of formation of the inactive AT III-factor Xa complex, heparins with Mr greater than 4,500 reduce the initial rate of thrombin generation in the presence of AT III in a concentration-dependent way. Heparin 206-214 coagulation factor X Homo sapiens 187-196 2920007-1 1989 We have proposed previously that the steps in coagulation most sensitive to inhibition by heparin are the thrombin-dependent amplification reactions, and that prothrombinase is formed in heparinized plasma only after Factor Xa activates Factor VIII and Factor V. These propositions were based on the demonstration that both heparin and Phe-Pro-Arg-CH2Cl completely inhibited 125I-prothrombin activation for up to 60 s when contact-activated plasma (CAP) was replenished with Ca2+. Heparin 187-194 coagulation factor X Homo sapiens 159-173 2920417-1 1989 The Heptest kit (Haemachem, Inc., St. Louis, MO) for quantifying heparin in plasma is based on heparin-mediated inhibition of factor Xa, resulting in prolongation of clotting time. Heparin 65-72 coagulation factor X Homo sapiens 126-135 2920417-1 1989 The Heptest kit (Haemachem, Inc., St. Louis, MO) for quantifying heparin in plasma is based on heparin-mediated inhibition of factor Xa, resulting in prolongation of clotting time. Heparin 95-102 coagulation factor X Homo sapiens 126-135 2713873-10 1989 This is particularly significant as regards the mechanism of action of heparin, because the synthetic pentasaccharide activates ATIII towards Factor Xa, but not towards thrombin. Heparin 71-78 coagulation factor X Homo sapiens 142-151 2920007-3 1989 Additional support for the above hypotheses is provided in this study by demonstrating that, when the activity of thrombin is suppressed by heparin (indirectly) or by Phe-Pro-Arg-CH2Cl (directly), exogenous Factor Xa reverses the ability of these two agents to inhibit prothrombin activation. Heparin 140-147 coagulation factor X Homo sapiens 207-216 2483705-6 1989 The assay is based on the inactivation of factor Xa by antithrombin III which is catalysed by heparin or smaller fragments of it. Heparin 94-101 coagulation factor X Homo sapiens 42-51 3238649-3 1988 In contact-activated plasma prothrombinase generation is inhibited by heparin, because heparin lowers the ambient concentrations of thrombin so that the feedback activation of factor VIII by thrombin is diminished. Heparin 70-77 coagulation factor X Homo sapiens 28-42 2562205-2 1989 More recently, assays have been developed which measure the inhibitory action of heparin on isolated coagulation enzymes, notably Factor Xa and thrombin, using specific amidolytic peptide substrates. Heparin 81-88 coagulation factor X Homo sapiens 130-139 3238649-3 1988 In contact-activated plasma prothrombinase generation is inhibited by heparin, because heparin lowers the ambient concentrations of thrombin so that the feedback activation of factor VIII by thrombin is diminished. Heparin 87-94 coagulation factor X Homo sapiens 28-42 2973992-4 1988 From the estimated concentration of heparan sulphate on the endothelial cell surface it is proposed that the non-thrombogenic property of blood vessels is due to the acceleration of the factor Xa or prothrombinase:ATIII interaction by the greater mass of surface-bound heparan sulphate rather than by the much smaller proportion of heparin-like molecules (with high affinity for antithrombin III) which may be present. Heparin 332-339 coagulation factor X Homo sapiens 186-195 2973992-4 1988 From the estimated concentration of heparan sulphate on the endothelial cell surface it is proposed that the non-thrombogenic property of blood vessels is due to the acceleration of the factor Xa or prothrombinase:ATIII interaction by the greater mass of surface-bound heparan sulphate rather than by the much smaller proportion of heparin-like molecules (with high affinity for antithrombin III) which may be present. Heparin 332-339 coagulation factor X Homo sapiens 199-213 3262615-3 1988 In the absence of heparin, the second-order rate constant of inhibition of factor Xa generated by factor IXa was 2.5-fold lower than the rate constant of inhibition of exogenous factor Xa. Heparin 18-25 coagulation factor X Homo sapiens 75-84 2851882-3 1988 The neutralizing effect of protamine chloride on the inhibition of factor Xa (clot test) was 95% for conventional heparin and 55% for low molecular weight heparin, whereas the effect of both heparin preparations on the thrombin inhibition could be completely neutralized. Heparin 114-121 coagulation factor X Homo sapiens 67-76 2851882-3 1988 The neutralizing effect of protamine chloride on the inhibition of factor Xa (clot test) was 95% for conventional heparin and 55% for low molecular weight heparin, whereas the effect of both heparin preparations on the thrombin inhibition could be completely neutralized. Heparin 155-162 coagulation factor X Homo sapiens 67-76 2851882-3 1988 The neutralizing effect of protamine chloride on the inhibition of factor Xa (clot test) was 95% for conventional heparin and 55% for low molecular weight heparin, whereas the effect of both heparin preparations on the thrombin inhibition could be completely neutralized. Heparin 155-162 coagulation factor X Homo sapiens 67-76 2849981-7 1988 Analysis of the results indicate that plasma fibrinopeptide A (FPA) levels correlate with anti-factor Xa (r = -0.45) and anti-thrombin (substrate) (r = -0.63) levels of UFH, but only with the anti-factor Xa levels (r = -0.41) of CY222. Heparin 169-172 coagulation factor X Homo sapiens 197-206 2849981-8 1988 These results suggest that the anti-factor Xa assay is currently the most suitable assay for monitoring low MW heparins such as CY222 in humans. Heparin 111-119 coagulation factor X Homo sapiens 36-45 2851191-7 1988 This concentration of the three LMW heparins increased, by approximately 70-fold, the rate of factor Xa inhibition by purified antithrombin III compared to the 50-fold increase seen with the two unfractionated heparins. Heparin 36-44 coagulation factor X Homo sapiens 94-103 3262615-7 1988 With unfractionated heparin above 40 ng/ml and antithrombin III at 200 nM, the apparent second-order rate constant of inhibition of exogenous and generated factor Xa were the same. Heparin 20-27 coagulation factor X Homo sapiens 156-165 2852498-8 1988 PCI also blocks the amidolytic activities of urokinase plasminogen activator (u-PA), thrombin and factor Xa on their chromogenic substrates in a heparin-dependent manner. Heparin 145-152 coagulation factor X Homo sapiens 98-107 2956835-6 1987 Heparin has additional antithrombotic actions, largely mediated through the formation of the same complex, but involving precursor elements such as factor Xa. Heparin 0-7 coagulation factor X Homo sapiens 148-157 3481140-1 1987 Heparin therapy was monitored with the activated partial thromboplastin time (APTT) and with chromogenic substrate assays (factor Xa and factor IIa inhibition) in 100 plasma samples from 47 patients. Heparin 0-7 coagulation factor X Homo sapiens 123-147 2442161-0 1987 Neutralization and binding of heparin by S protein/vitronectin in the inhibition of factor Xa by antithrombin III. Heparin 30-37 coagulation factor X Homo sapiens 84-93 2442161-2 1987 The interference of the heparin-neutralizing plasma component S protein (vitronectin) (Mr = 78,000) with heparin-catalyzed inhibition of coagulation factor Xa by antithrombin III was investigated in plasma and in a purified system. Heparin 105-112 coagulation factor X Homo sapiens 149-158 2442161-4 1987 Using purified components in the presence of heparin, S protein induced a concentration-dependent reduction of the inhibition rate of factor Xa by antithrombin III. Heparin 45-52 coagulation factor X Homo sapiens 134-143 3621562-1 1987 We describe a fully automated assay for determining effective heparin activity in plasma, based on heparin-catalyzed inhibition of Factor Xa (EC 3.4.21.6) by antithrombin III (AT III). Heparin 62-69 coagulation factor X Homo sapiens 131-140 3621562-1 1987 We describe a fully automated assay for determining effective heparin activity in plasma, based on heparin-catalyzed inhibition of Factor Xa (EC 3.4.21.6) by antithrombin III (AT III). Heparin 99-106 coagulation factor X Homo sapiens 131-140 3621562-2 1987 Residual Factor Xa is determined kinetically by the Du Pont aca discrete clinical analyzer with a chromogenic substrate and is inversely related to heparin activity. Heparin 148-155 coagulation factor X Homo sapiens 9-18 2445746-4 1987 The abilities of heparin fractions, Mr 7,800-18,800, with high affinity for antithrombin, and of the International Heparin Standard, to accelerate the inactivation of thrombin and Factor Xa by antithrombin were readily neutralized by S protein/vitronectin. Heparin 17-24 coagulation factor X Homo sapiens 180-189 2445746-4 1987 The abilities of heparin fractions, Mr 7,800-18,800, with high affinity for antithrombin, and of the International Heparin Standard, to accelerate the inactivation of thrombin and Factor Xa by antithrombin were readily neutralized by S protein/vitronectin. Heparin 115-122 coagulation factor X Homo sapiens 180-189 2445746-7 1987 Furthermore, S protein/vitronectin neutralized the anti-Factor Xa activity of a synthetic pentasaccharide comprising the antithrombin-binding sequence of heparin. Heparin 154-161 coagulation factor X Homo sapiens 56-65 3606581-0 1987 The effect of Ca2+, phospholipid and factor V on the anti-(factor Xa) activity of heparin and its high-affinity oligosaccharides. Heparin 82-89 coagulation factor X Homo sapiens 59-68 2823841-3 1987 The course of the activated partial thromboplastin time showed no difference between the medications given, whereas the inhibition of factor Xa was significantly stronger after application of all dosages of LMWH than after unfractionated heparin injections. Heparin 238-245 coagulation factor X Homo sapiens 134-143 3617870-3 1987 The dose of the low molecular weight heparin ranged individually from 2,500 to 12,000 units once a day subcutaneously and was adjusted on the basis of the general bleeding tendency of the patient and the specific anticoagulant effect on factor Xa. Heparin 37-44 coagulation factor X Homo sapiens 237-246 3585139-4 1987 Heparin, and low-affinity heparin, reduced the anti-Xa activity of HTGL, suggesting that heparin and factor Xa compete for the same binding sites on the lipase molecule. Heparin 0-7 coagulation factor X Homo sapiens 101-110 3585139-4 1987 Heparin, and low-affinity heparin, reduced the anti-Xa activity of HTGL, suggesting that heparin and factor Xa compete for the same binding sites on the lipase molecule. Heparin 26-33 coagulation factor X Homo sapiens 101-110 2443128-1 1987 Heparin catalyses the inhibition of two key enzymes of blood coagulation, namely Factor Xa and thrombin, by enhancing the antiproteinase activities of plasma antithrombin III and heparin cofactor II. Heparin 0-7 coagulation factor X Homo sapiens 81-90 3606581-6 1987 These results indicate that in the presence of Ca2+/phospholipid/Factor V optimum inhibition of Factor Xa requires a saccharide sequence of heparin additional to that involved in binding to antithrombin III. Heparin 140-147 coagulation factor X Homo sapiens 96-105 3606581-7 1987 The use of free enzyme for the assessment of anti-(Factor Xa) activity of low-Mr heparin fractions could give misleading results. Heparin 81-88 coagulation factor X Homo sapiens 51-60 3481165-2 1987 The heparin surface was highly thromboresistant in contact with blood, as manifested by minimal cell adhesion and a pronounced capacity to inactivate coagulation enzymes such as thrombin and factor Xa. Heparin 4-11 coagulation factor X Homo sapiens 191-200 3590093-1 1987 The neutralization of heparin by active site blocked meizothrombin and thrombin, prothrombin fragment 1.2, fragment 1 and fragment 2 was probed by the heparin-dependent factor Xa inactivation by antithrombin III (AT III). Heparin 22-29 coagulation factor X Homo sapiens 169-178 3590093-4 1987 However, after isolation of the reaction products, both thrombin and prothrombin fragment 1.2 exhibited heparin neutralizing properties in the factor Xa inactivation reaction. Heparin 104-111 coagulation factor X Homo sapiens 143-152 3590093-6 1987 Prothrombin fragment 1, when present at 125 nM, caused a 50% reduction of the heparin-dependent rate of inactivation of factor Xa and prothrombin fragment 2 had no effect at all. Heparin 78-85 coagulation factor X Homo sapiens 120-129 3782075-0 1986 Role of ternary complexes, in which heparin binds both antithrombin and proteinase, in the acceleration of the reactions between antithrombin and thrombin or factor Xa. Heparin 36-43 coagulation factor X Homo sapiens 158-167 3782075-2 1986 Moreover, all high-affinity oligosaccharides and heparins enhanced, to a similar extent, the amount of free proteolytically modified antithrombin cleaved at the reactive bond by Factor Xa. Heparin 49-57 coagulation factor X Homo sapiens 178-187 3790498-8 1986 It is our conclusion that factor Xa when acting in prothrombinase on prothrombin is profoundly protected from inhibition by antithrombin III in the absence as well as in the presence of heparin. Heparin 186-193 coagulation factor X Homo sapiens 26-35 3798412-6 1986 This suggests that Factor Xa and antithrombin III have similar affinities for this immobilized heparin, unlike the situation for thrombin (Thromb-Res., 20, 543-554, 1980). Heparin 95-102 coagulation factor X Homo sapiens 19-28 3936965-9 1985 A LMW-heparin dose was used that produced plasma anti-FXa-activity of 0.5 to 0.9 U/ml (initial dose: 30 to 40; dose/hr: 8 to 15 anti-FXa-units/kg body wt). Heparin 6-13 coagulation factor X Homo sapiens 54-57 3698718-5 1986 Low-dose heparin acts through its effect of factor Xa and activation of antithrombin III; DHE selectively increases venous smooth muscle tone to accelerate venous blood flow velocity and minimize venous pooling. Heparin 9-16 coagulation factor X Homo sapiens 44-53 3766461-6 1986 The authors have also studied the effect of the divalent cations (Ca+2, Mg+2, Zn+2, and Sr+2) on the anti-Factor Xa activity of heparin to determine whether the calcium-dependent increase in the aPTT was due to an increase in the anti-Factor Xa activity. Heparin 128-135 coagulation factor X Homo sapiens 106-115 3766461-7 1986 The anti-Factor Xa activity of heparin was measured using chromogenic substrate S-2251, purified Factor Xa, and excess antithrombin III. Heparin 31-38 coagulation factor X Homo sapiens 9-18 3766461-7 1986 The anti-Factor Xa activity of heparin was measured using chromogenic substrate S-2251, purified Factor Xa, and excess antithrombin III. Heparin 31-38 coagulation factor X Homo sapiens 97-106 3766461-12 1986 Furthermore, divalent cations play an important role in regulating the anti-Factor Xa activity of heparin in vitro. Heparin 98-105 coagulation factor X Homo sapiens 76-85 3800942-0 1986 The relative molecular mass dependence of the anti-factor Xa properties of heparin. Heparin 75-82 coagulation factor X Homo sapiens 51-60 3800942-1 1986 The effect of heparin fractions of various Mr, with high affinity for antithrombin III, on the kinetics of the reaction between factor Xa and antithrombin III have been studied using purified human proteins. Heparin 14-21 coagulation factor X Homo sapiens 128-137 3800942-5 1986 The disparity in these rates of inhibition was shown to be due to a change in the Km for factor Xa when a two-substrate model of heparin catalysis was used. Heparin 129-136 coagulation factor X Homo sapiens 89-98 3800942-7 1986 These data suggest that the increased rates of inhibition observed with heparins of higher Mr may be due to an involvement of heparin binding to factor Xa as well as to antithrombin III. Heparin 72-80 coagulation factor X Homo sapiens 145-154 3800942-7 1986 These data suggest that the increased rates of inhibition observed with heparins of higher Mr may be due to an involvement of heparin binding to factor Xa as well as to antithrombin III. Heparin 72-79 coagulation factor X Homo sapiens 145-154 3740376-5 1986 At the latest eight hours after the beginning of heparin-infusion the steady state of plasma heparin concentration was reached in 100%, but only in 56.67% it equalled the therapeutical factor Xa inhibition-level of 0.10 IE/ml to 0.20 IE/ml (= 0.077 USP-E/ml to 0.154 USP-E/ml). Heparin 49-56 coagulation factor X Homo sapiens 185-194 3744134-3 1986 Comparison of a low molecular weight heparin, Kabi 2165, revealed that it can inhibit fibrin formation in the extracorporeal circulation, that this property is largely reflected in its anti-factor Xa activity in plasma, and that a useful and effective dose of Kabi 2165 for haemodialysis may be 4,000 anti-factor Xa U intravenous bolus + 750 anti-factor Xa U/h intravenous maintenance infusion. Heparin 37-44 coagulation factor X Homo sapiens 190-199 3744134-3 1986 Comparison of a low molecular weight heparin, Kabi 2165, revealed that it can inhibit fibrin formation in the extracorporeal circulation, that this property is largely reflected in its anti-factor Xa activity in plasma, and that a useful and effective dose of Kabi 2165 for haemodialysis may be 4,000 anti-factor Xa U intravenous bolus + 750 anti-factor Xa U/h intravenous maintenance infusion. Heparin 37-44 coagulation factor X Homo sapiens 306-315 3744134-3 1986 Comparison of a low molecular weight heparin, Kabi 2165, revealed that it can inhibit fibrin formation in the extracorporeal circulation, that this property is largely reflected in its anti-factor Xa activity in plasma, and that a useful and effective dose of Kabi 2165 for haemodialysis may be 4,000 anti-factor Xa U intravenous bolus + 750 anti-factor Xa U/h intravenous maintenance infusion. Heparin 37-44 coagulation factor X Homo sapiens 306-315 2411283-4 1985 Standard heparin was the only sulphated polysaccharide that could equally inhibit thrombin generation and enhance the inactivation of factor Xa and thrombin by plasma. Heparin 9-16 coagulation factor X Homo sapiens 134-143 4082106-3 1985 injection of 100 USP units/kg body weight lipoprotein lipase (LPL) activity, and inhibition of factor Xa decreased with a half life twice as long after LMW heparin compared to normal heparin (p less than 0.05). Heparin 156-163 coagulation factor X Homo sapiens 95-104 4082106-5 1985 The area under the activity time curve (AUC) of LPL and factor Xa was double with LMW heparin (p less than 0.05). Heparin 86-93 coagulation factor X Homo sapiens 56-65 4082106-6 1985 S.c. administration showed that the AUC of LMW heparin on the factor Xa inhibition was 10 times larger compared to normal heparin. Heparin 47-54 coagulation factor X Homo sapiens 62-71 6422851-6 1984 In the presence of heparin the inhibition of thrombin as well as factor Xa was enhanced. Heparin 19-26 coagulation factor X Homo sapiens 65-74 4002198-9 1985 The incomplete inhibitory effect of protamine chloride on LPL, HTGL and factor Xa activities of LMW heparin indicate that protamine chloride requires more than 14 saccharide units in the heparin molecule for interaction. Heparin 100-107 coagulation factor X Homo sapiens 72-81 6734448-3 1984 Low-molecular heparin caused a ten-fold stronger inhibition of factor Xa. Heparin 14-21 coagulation factor X Homo sapiens 63-72 6734448-5 1984 Half-life of heparin measured in terms of the inhibition of factor Xa was 5.5 hours for the low-molecular and 3.5 hours for the commercial preparation. Heparin 13-20 coagulation factor X Homo sapiens 60-69 6734448-6 1984 These results indicate that low-molecular heparin has a high specificity in the inhibition of factor Xa. Heparin 42-49 coagulation factor X Homo sapiens 94-103 6509363-0 1984 Effects of heparin fractions of different affinities to antithrombin III and thrombin on the inactivation of thrombin and factor Xa by antithrombin III. Heparin 11-18 coagulation factor X Homo sapiens 122-131 6509363-2 1984 There was a good correlation between heparin affinity for antithrombin III and its ability to enhance the inactivation of thrombin and factor Xa. Heparin 37-44 coagulation factor X Homo sapiens 135-144 6382161-8 1984 The two most probable sites of action of heparin are: inhibition of thrombin and frustration of the feedback loops and/or inhibition of factor Xa. Heparin 41-48 coagulation factor X Homo sapiens 136-145 6735276-1 1984 Spectrophotometric heparin assays which are based on the catalytic effect of heparin on either the inactivation of thrombin or that of factor Xa by antithrombin III, were adapted for use in a laboratory batch analyzer. Heparin 19-26 coagulation factor X Homo sapiens 135-144 6198531-8 1984 The therapeutic effects of heparin were assessed by prolonged APTT (45-250 sec) and elevated Anti-FXa activity (0.2-1.2 u/ml of plasma heparin concentration) as an indicator for the evaluation of anticoagulation activity and by normalized FPA, Fbg, FDP, Plg and AT III as an indicator for evaluation of antithrombolic activity. Heparin 27-34 coagulation factor X Homo sapiens 98-101 6222069-7 1983 On this basis, we suggest that high in vivo rates of thrombin generation may lead to the sequestration of Factor Xa on the platelet surface and hence allow this serine protease to resist the action of heparin until the complex is cleared from the circulation. Heparin 201-208 coagulation factor X Homo sapiens 106-115 6310817-6 1983 This conclusion was further supported by the ability of heparin to reverse the inhibitory effect of altered factor Xa when the anticoagulant was added simultaneously to platelets. Heparin 56-63 coagulation factor X Homo sapiens 108-117 6607710-4 1983 The purified vertebrate inhibitors all show the following physical and functional homologies to human antithrombin: (i) heparin-enhanced inhibition of both bovine thrombin and human Factor Xa, (ii) molecular masses of approximately 60,000, and (iii) heparin-induced increases in ultraviolet fluorescence. Heparin 120-127 coagulation factor X Homo sapiens 182-191 6651824-0 1983 Structure-activity relationship in heparin: a synthetic pentasaccharide with high affinity for antithrombin III and eliciting high anti-factor Xa activity. Heparin 35-42 coagulation factor X Homo sapiens 136-145 6577437-4 1983 The kinetic parameters for the heparin-catalyzed antithrombin III/thrombin and antithrombin III/factor Xa reactions differed in terms of apparent maximum velocity (Vmax) and apparent heparin-protease dissociation constant values. Heparin 31-38 coagulation factor X Homo sapiens 96-105 6822493-5 1983 Differences between thrombin and Factor Xa at low (nanomolar) concentrations of heparin were evident in this rate constant and the relative affinities for the heparin-antithrombin complex (Km for Factor Xa = 100 nM; Km for thrombin less than or equal to 2 nM). Heparin 80-87 coagulation factor X Homo sapiens 196-205 6822493-5 1983 Differences between thrombin and Factor Xa at low (nanomolar) concentrations of heparin were evident in this rate constant and the relative affinities for the heparin-antithrombin complex (Km for Factor Xa = 100 nM; Km for thrombin less than or equal to 2 nM). Heparin 80-87 coagulation factor X Homo sapiens 33-42 6847629-1 1983 Heparin fractions of differing Mr (7800-18 800) prepared from commercial heparin by gel filtration and affinity chromatography on immobilized anti-thrombin III had specific activities when determined by anti-Factor Xa and anti-thrombin assays that ranged from 228 to 448 units/mg. Heparin 0-7 coagulation factor X Homo sapiens 208-217 6822493-7 1983 At high heparin concentrations (micromolar), the kinetic parameters for Factor Xa were unchanged but the Km for thrombin increased dramatically to 100 nM. Heparin 8-15 coagulation factor X Homo sapiens 72-81 7157229-6 1982 The inactivation of thrombin or factor Xa by antithrombin is catalysed by the presence in the mixture of these insoluble materials as it is with soluble heparin. Heparin 153-160 coagulation factor X Homo sapiens 32-41 7349668-5 1980 Thrombin and Factor Xa were instantaneously inhibited by AT III in the presence of soluble heparin. Heparin 91-98 coagulation factor X Homo sapiens 13-22 7085627-3 1982 Both clotting and amidolytic chromogenic assays were used to measure heparin-potentiated inhibition of both thrombin and Factor Xa. Heparin 69-76 coagulation factor X Homo sapiens 121-130 6977539-4 1982 As in the latter reaction, the formation of the modified antithrombin by Factor Xa was increased in the presence of heparin, while only small amounts were produced by Factor IXa both in the absence and presence of the polysaccharide. Heparin 116-123 coagulation factor X Homo sapiens 73-82 7292448-0 1981 Influence of variations in the chemical structure of heparin on its anticoagulant and anti-factor Xa activities. Heparin 53-60 coagulation factor X Homo sapiens 91-100 7222474-11 1981 5) Finally there is also an inhibitory effect of heparin on the activated Stuart-Prower factor. Heparin 49-56 coagulation factor X Homo sapiens 74-94 7112518-0 1982 Demonstration of a direct anti-factor Xa activity in certain heparin-related glycosaminoglycans. Heparin 61-68 coagulation factor X Homo sapiens 31-40 7225714-2 1981 2 Only dermatan sulphate preparations of considerable heparin content potentiate AT III inhibition of thrombin, factor Xa and plasmin. Heparin 54-61 coagulation factor X Homo sapiens 112-121 7349668-1 1980 The reactions of covalently immobilized heparin, abbreviated as I-Hep, with thrombin or Factor Xa were investigated both in the presence and absence of antithrombin III, AT III. Heparin 40-47 coagulation factor X Homo sapiens 88-97 7368180-0 1980 A differential effect of low-affinity heparin on the inhibition of thrombin and factor Xa by antithrombin. Heparin 38-45 coagulation factor X Homo sapiens 80-89 7189413-4 1980 LDL inhibited the high molecular weight (but not low molecular weight) heparin accelerated neutralisation of factor Xa by antithrombin III. Heparin 71-78 coagulation factor X Homo sapiens 109-118 7189413-6 1980 These observations suggest that certain plasma lipoproteins may selectively modulate the inhibitory action of heparin against factor Xa. Heparin 110-117 coagulation factor X Homo sapiens 126-135 7417594-3 1980 Heparin stimulates the inactivation of Factor Xa and thrombin by AT III. Heparin 0-7 coagulation factor X Homo sapiens 39-48 7191289-1 1980 2nd communication: Chemical analysis of the carbohydrate content and determination of the biological activity of a new potent heparin preparation in vitro, using protamine neutralization and amidolytic methods for factor Xa and thrombin. Heparin 126-133 coagulation factor X Homo sapiens 214-223 7191289-2 1980 A new potent heparin preparation was further characterized for carbohydrate content and for biological activities in vitro using the protamine neutralization test and amidolytic methods for factor Xa and thrombin. Heparin 13-20 coagulation factor X Homo sapiens 190-199 7191289-5 1980 The amidolytic method using chromogenic substrates S-2222 for factor Xa and S-2238 for thrombin demonstrated that the new heparin was also at least two times more effective than commercial heparin in increasing the rate of inactivation of these serin proteases through antithrombin III. Heparin 122-129 coagulation factor X Homo sapiens 62-71 7417594-10 1980 Hep, like soluble AT III and heparin, instantaneously neutralized both thrombin and Factor Xa. Heparin 29-36 coagulation factor X Homo sapiens 84-93 7409614-1 1980 The heparin-antagonizing effect of human alpha 1-acid glycoprotein (alpha 1-acid GP) was studied by activated partial thromboplastin time (APTT) and by a factor Xa assay for heparin using a chromogenic substrate for factor Xa. Heparin 4-11 coagulation factor X Homo sapiens 154-163 7409614-1 1980 The heparin-antagonizing effect of human alpha 1-acid glycoprotein (alpha 1-acid GP) was studied by activated partial thromboplastin time (APTT) and by a factor Xa assay for heparin using a chromogenic substrate for factor Xa. Heparin 4-11 coagulation factor X Homo sapiens 216-225 658785-4 1978 Heparin accelerates the saturation of antithrombin with factor Xa. Heparin 0-7 coagulation factor X Homo sapiens 56-65 486539-0 1979 Interactions between heparin and factor Xa. Heparin 21-28 coagulation factor X Homo sapiens 33-42 486539-3 1979 Heparin was found to inhibit the rate of prothrombin activation by Factor Xa, calcium and phospholipid. Heparin 0-7 coagulation factor X Homo sapiens 67-76 486539-7 1979 In accord with this, binding studies demonstrated that heparin could displace Factor Xa, and in separate experiments, prothrombin, from phospholipid vesicles. Heparin 55-62 coagulation factor X Homo sapiens 78-87 476156-0 1979 Evidence for a plasma inhibitor of the heparin accelerated inhibition of factor Xa by antithrombin III. Heparin 39-46 coagulation factor X Homo sapiens 73-82 486155-1 1979 The inactivation of thrombin and factor Xa by antithrombin was determined in the presence of heparin fractions of different molecular weights and with high affinity for antithrombin. Heparin 93-100 coagulation factor X Homo sapiens 33-42 720957-2 1978 When factor Xa was added to a system containing antithrombin III in excess and heparin in low concentration, the amount of factor Xa immediately inactivated was found to be a function of the concentration of heparin. Heparin 79-86 coagulation factor X Homo sapiens 5-14 720957-2 1978 When factor Xa was added to a system containing antithrombin III in excess and heparin in low concentration, the amount of factor Xa immediately inactivated was found to be a function of the concentration of heparin. Heparin 79-86 coagulation factor X Homo sapiens 123-132 720957-2 1978 When factor Xa was added to a system containing antithrombin III in excess and heparin in low concentration, the amount of factor Xa immediately inactivated was found to be a function of the concentration of heparin. Heparin 208-215 coagulation factor X Homo sapiens 5-14 146278-0 1977 Role of heparin in the inactivation of thrombin, factor Xa, and plasmin by antithrombin III. Heparin 8-15 coagulation factor X Homo sapiens 49-58 720957-2 1978 When factor Xa was added to a system containing antithrombin III in excess and heparin in low concentration, the amount of factor Xa immediately inactivated was found to be a function of the concentration of heparin. Heparin 208-215 coagulation factor X Homo sapiens 123-132 1202536-2 1975 Heparin is a true anticoagulant, and directly opposes fibrin formation (antithrombotic action) and potentiates the inactivation of prothrombinase ; this global action, immediately effective, makes heparin undoubtedly superior to the antivitamins K. Nevertheless, its action on thrombogenesis is incomplete : it reacts only slightly or not at all on platelet aggregation and fibrinolysis. Heparin 0-7 coagulation factor X Homo sapiens 131-145 969504-4 1976 Second, low-dose heparin probably works by augmenting the effect of the naturally occurring inhibitor to Factor Xa. Heparin 17-24 coagulation factor X Homo sapiens 105-114 47195-0 1975 Effect of heparin on the neutralization of factor Xa and thrombin by the plasma alpha-2-globulin inhibitor. Heparin 10-17 coagulation factor X Homo sapiens 43-52 888033-7 1977 The factor Xa inhibition assay measured heparin levels most precisely and mirrored the A-PTT results in all but one instance. Heparin 40-47 coagulation factor X Homo sapiens 4-13 1123560-2 1975 Factor Xa is prepared in a concentration adjusted to produce a clotting time of 18 to 20 seconds when heparin-free plasma is tested in the system. Heparin 102-109 coagulation factor X Homo sapiens 0-9 1202536-2 1975 Heparin is a true anticoagulant, and directly opposes fibrin formation (antithrombotic action) and potentiates the inactivation of prothrombinase ; this global action, immediately effective, makes heparin undoubtedly superior to the antivitamins K. Nevertheless, its action on thrombogenesis is incomplete : it reacts only slightly or not at all on platelet aggregation and fibrinolysis. Heparin 197-204 coagulation factor X Homo sapiens 131-145 4853677-1 1974 Assay based on factor-Xa inactivation by heparin and antifactor Xa. Heparin 41-48 coagulation factor X Homo sapiens 15-24 33925501-2 2021 As a result, a number of nonvitamin K antagonist oral anticoagulants (NOAC) that directly target the enzymatic activity of factor II and factor Xa have been successfully licensed providing a more predictable effect and better safety profile compared to conventional anticoagulants (heparins and vitamin K antagonists (VKAs)). Heparin 282-290 coagulation factor X Homo sapiens 137-146 33984481-2 2022 Postoperative unfractionated heparin dosing can be monitored by activated partial thromboplastin time (APTT) or by anti-factor Xa activity (anti-Xa). Heparin 29-36 coagulation factor X Homo sapiens 120-129 32885997-0 2021 A Systemwide Approach for Navigating the Dilemma of Oral Factor Xa Inhibitor Interference With Unfractionated Heparin Anti-Factor Xa Concentrations. Heparin 110-117 coagulation factor X Homo sapiens 57-66 32885997-0 2021 A Systemwide Approach for Navigating the Dilemma of Oral Factor Xa Inhibitor Interference With Unfractionated Heparin Anti-Factor Xa Concentrations. Heparin 110-117 coagulation factor X Homo sapiens 123-132 32885997-1 2021 BACKGROUND: Oral factor Xa inhibitors are known to significantly increase heparin anti-Xa concentrations, which leads to inaccuracies when monitoring intravenous unfractionated heparin (IV UFH). Heparin 74-81 coagulation factor X Homo sapiens 17-26 32885997-1 2021 BACKGROUND: Oral factor Xa inhibitors are known to significantly increase heparin anti-Xa concentrations, which leads to inaccuracies when monitoring intravenous unfractionated heparin (IV UFH). Heparin 177-184 coagulation factor X Homo sapiens 17-26 32959678-3 2021 Clinically, UFH is monitored through activated clotting time (ACT), activated partial thromboplastin time (aPTT), and anti-factor Xa assay. Heparin 12-15 coagulation factor X Homo sapiens 123-132 32959678-12 2021 CONCLUSION AND RELEVANCE: The adaption of a multifaceted anticoagulation protocol using anti-factor Xa assay may provide a better prediction of heparin dosing in adults ECMO patients compared with the conventional ACT-based protocol. Heparin 144-151 coagulation factor X Homo sapiens 93-102 33026569-3 2021 We aimed to characterize the burden of CRRT filter clotting in COVID-19 infection and to describe a CRRT anticoagulation protocol that used anti-factor Xa levels for systemic heparin dosing. Heparin 175-182 coagulation factor X Homo sapiens 145-154 33026569-10 2021 An anticoagulation protocol using systemic unfractionated heparin, dosed by anti-factor Xa levels is reasonable approach to anticoagulation in this population. Heparin 58-65 coagulation factor X Homo sapiens 81-90 33128209-5 2021 The adult and adapted models were used to predict the time courses of anti-factor Xa activity (aXa) and activated partial thromboplastin time (aPTT) in patients receiving UFH infusion. Heparin 171-174 coagulation factor X Homo sapiens 75-84 32833716-3 2021 METHODS: In the derivation cohort then in the validation cohort, via receiver operatingcharacteristics (ROC) curve analysis, we evaluated the ability of heparin anti-Xaassay to detect levels of factor-Xa inhibitors above or below the abovementioned safety thresholds recommended for an invasive procedure (screening test). Heparin 153-160 coagulation factor X Homo sapiens 194-203 33860518-4 2021 Thus, by activating antithrombin, heparin mainly inhibits factor Xa and thrombin, whereas VKAs lower the levels of the vitamin K-dependent clotting factors. Heparin 34-41 coagulation factor X Homo sapiens 58-67 33216354-1 2021 BACKGROUND: Some cancer patients who are diagnosed with thromboembolism may require dual treatment with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) and factor Xa inhibitors (low-molecular-weight heparin [LMWH] or direct oral anticoagulants [DOACs]). Heparin 237-244 coagulation factor X Homo sapiens 194-203 32833716-5 2021 In a validation cohort, the estimated level of each factor-Xa inhibitor was thus inferred from heparin anti-Xa activity. Heparin 95-102 coagulation factor X Homo sapiens 52-61 32833716-7 2021 RESULTS: Among 989 (355 patients) and 756 blood samples (420 patients) in the derivation and validation cohort, there was a strong linear relationship between heparin anti-Xa activities and factor-Xa inhibitors measured level (r = 0.99 [95% confidence interval {CI}, 0.99-0.99]). Heparin 159-166 coagulation factor X Homo sapiens 190-199 33512867-0 2021 Enoxaparin Dose Requirements to Achieve Therapeutic Low-molecular-weight Heparin Anti-factor Xa Levels in Infants and Young Children. Heparin 73-80 coagulation factor X Homo sapiens 86-95 33302210-0 2021 Discordance in activated partial thromboplastin time and anti-factor Xa levels in COVID-19 patients on heparin therapy. Heparin 103-110 coagulation factor X Homo sapiens 62-71 33176060-1 2021 BACKGROUND: Heparin enhances the ability of the plasma protease inhibitor, antithrombin, to neutralize coagulation factor Xa and thrombin. Heparin 12-19 coagulation factor X Homo sapiens 115-124 33176060-4 2021 METHODS: Inhibition of factor Xa and thrombin by antithrombin in the presence of different heparins and skeletal muscle myosin or cardiac myosin was studied by measuring inhibition of each enzyme"s chromogenic substrate hydrolysis. Heparin 91-99 coagulation factor X Homo sapiens 23-32 33176060-5 2021 RESULTS AND CONCLUSIONS: Skeletal muscle myosin and cardiac myosin neutralized unfractionated heparin"s enhancement of antithrombin"s inhibition of purified factor Xa and thrombin. Heparin 94-101 coagulation factor X Homo sapiens 157-166 32441664-12 2020 Conclusions Our study demonstrates that the choice of the anti-FXa method is particularly important for UFH and LMWH measurement. Heparin 104-107 coagulation factor X Homo sapiens 63-66 32888192-2 2021 INTRODUCTION: Standard subcutaneous low-molecular-weight heparin (LMWH) thromboprophylaxis yields low anti-factor Xa activity in patients in the intensive care unit (ICU). Heparin 57-64 coagulation factor X Homo sapiens 107-116 33214783-0 2020 Evaluation of Heparin Anti-Factor Xa Levels Following Antithrombin Supplementation in Pediatric Patients Supported With Extracorporeal Membrane Oxygenation. Heparin 14-21 coagulation factor X Homo sapiens 27-36 32433187-0 2020 Perils of Antithrombotic Transitions: Effect of Oral Factor Xa Inhibitors on the Heparin Antifactor Xa Assay. Heparin 81-88 coagulation factor X Homo sapiens 53-62 32677060-0 2020 The relationship between the initial anti-factor Xa measurement and the duration of direct oral anticoagulant influence in patients transitioning to heparin. Heparin 149-156 coagulation factor X Homo sapiens 42-51 32677060-2 2020 Factor-Xa inhibitors influence the heparin calibrated anti-factor Xa assay. Heparin 35-42 coagulation factor X Homo sapiens 0-9 32677060-2 2020 Factor-Xa inhibitors influence the heparin calibrated anti-factor Xa assay. Heparin 35-42 coagulation factor X Homo sapiens 59-68 32677060-3 2020 The University of Virginia (UVA) Medical Center utilized a corrected anti-factor Xa assay (c-AXA) during this transition period, which removes DOAC-mediated anti-factor Xa activity (d-AXA) and reflects heparin-specific activity. Heparin 202-209 coagulation factor X Homo sapiens 74-83 32216028-0 2020 Anti-Factor IIa (FIIa) Heparin Assay for Patients on Direct Factor Xa (FXa) Inhibitors. Heparin 23-30 coagulation factor X Homo sapiens 60-69 32216028-0 2020 Anti-Factor IIa (FIIa) Heparin Assay for Patients on Direct Factor Xa (FXa) Inhibitors. Heparin 23-30 coagulation factor X Homo sapiens 71-74 32216028-1 2020 BACKGROUND: Direct factor Xa (FXa) inhibitors are increasingly prescribed for outpatients, and those transitioning to unfractionated heparin (UFH) for hospital admission are monitored via an anti-FXa assay. Heparin 142-145 coagulation factor X Homo sapiens 196-199 32422680-5 2020 Results demonstrate the inhibitory activity of AT-T90S toward thrombin and factor Xa has been impaired three- to fivefold in both the absence and presence of heparin. Heparin 158-165 coagulation factor X Homo sapiens 75-84 32422680-7 2020 Kinetic analysis revealed the stoichiometry of AT-T90S inhibition of both thrombin and factor Xa has been elevated by three- to fourfold in both the absence and presence of heparin, suggesting that the reactivity of coagulation proteases with AT-T90S has been elevated in the substrate pathway. Heparin 173-180 coagulation factor X Homo sapiens 87-96 32526007-0 2020 Design and Implementation of an Anti-Factor Xa Heparin Monitoring Protocol. Heparin 47-54 coagulation factor X Homo sapiens 37-46 32526007-1 2020 BACKGROUND: The VA Northeast Ohio Healthcare System introduced a new nurse-driven anti-factor Xa (anti-Xa) protocol for monitoring unfractionated heparin to replace the previous activated partial thromboplastin time protocol. Heparin 146-153 coagulation factor X Homo sapiens 87-96 32526007-3 2020 METHODS: An interdisciplinary team of providers collaborated to develop and implement a nurse-driven, facility-wide anti-factor Xa protocol for monitoring unfractionated heparin therapy. Heparin 170-177 coagulation factor X Homo sapiens 121-130 32187355-5 2020 Induction of FXa activity by ICs containing IgG antibodies to platelet factor 4 (PF4) involved in heparin-induced thrombocytopenia (HIT), beta-2-glycoprotein-1 implicated in antiphospholipid syndrome, or red blood cells coated with anti-(alpha)-Rh(D) antibodies that mediate hemolysis in vivo was inhibited by a humanized monoclonal antibody (mAb) that blocks IgG binding to human FcRn. Heparin 98-105 coagulation factor X Homo sapiens 13-16 31797980-1 2019 Heparin is a widely used anticoagulant which inhibits factor Xa and thrombin through potentiation of antithrombin. Heparin 0-7 coagulation factor X Homo sapiens 54-63 31893201-12 2019 Therefore, these types of anomalies should be actively looked for, particularly in young patients with DVT.Treatment with low molecular weight heparin or oral anticoagulation medication is the mainstay of therapy, directed towards preventing thrombosis or its recurrence.A direct factor Xa inhibitor could be a possible alternative to vitamin K antagonists in these patients, despite the lack of clinical evidence supporting its use at the moment. Heparin 143-150 coagulation factor X Homo sapiens 280-289 30813751-1 2019 Background: Lab tests such as activated partial thromboplastin time (aPTT) or anti-factor Xa (anti-Xa) levels are typically used to monitor intravenous unfractionated heparin (IV heparin), with recent evidence suggesting that anti-Xa levels may provide a more accurate measure of anticoagulation. Heparin 179-186 coagulation factor X Homo sapiens 83-92 31243789-0 2019 Clinical outcomes with unfractionated heparin monitored by anti-factor Xa vs. activated partial Thromboplastin time. Heparin 38-45 coagulation factor X Homo sapiens 64-73 31251821-6 2019 This case highlights the potential complications of using UFH anticoagulation following reversal of factor Xa inhibitors with andexanet alfa and underscores the importance of peri-procedural anticoagulation planning. Heparin 58-61 coagulation factor X Homo sapiens 100-109 30961988-0 2019 Anti-Factor Xa-Based Monitoring of Unfractionated Heparin: Clinical Outcomes in a Pediatric Cohort. Heparin 50-57 coagulation factor X Homo sapiens 5-14 31472056-7 2019 In addition to above mechanisms, possibly the infused protamine binds heparin and causes the coagulation cascade to activate heparin-AT complex on thrombin beside activating FXIa, FXa and FIXa and causing the re-use of Ca2+. Heparin 127-134 coagulation factor X Homo sapiens 182-185 31251821-1 2019 The authors describe a case of unfractionated heparin (UFH) unresponsiveness in the operating room secondary to reversal of rivaroxaban with coagulation factor Xa (recombinant) inactivated-zhzo (andexanet alfa). Heparin 46-53 coagulation factor X Homo sapiens 153-162 31251821-1 2019 The authors describe a case of unfractionated heparin (UFH) unresponsiveness in the operating room secondary to reversal of rivaroxaban with coagulation factor Xa (recombinant) inactivated-zhzo (andexanet alfa). Heparin 55-58 coagulation factor X Homo sapiens 153-162 30947118-5 2019 The resulting surface combines the anti-coagulant (anti-FXa) function provided by the heparin and the anti-platelet activity of the catalytically produced NO. Heparin 86-93 coagulation factor X Homo sapiens 56-59 30961988-5 2019 The median unfractionated heparin dose required to reach therapeutic Anti-FXa goal was significantly greater in infants compared with older children (P <.0001). Heparin 26-33 coagulation factor X Homo sapiens 74-77 30961988-10 2019 CONCLUSIONS: Using an anti-FXa-based nomogram to monitor unfractionated heparin in children is feasible. Heparin 72-79 coagulation factor X Homo sapiens 27-30 29173042-1 2018 Antithrombin (AT) is a serpin that inhibits mainly thrombin and fXa after being activated by binding to glycosaminoglycans as heparin and heparan sulfate. Heparin 126-133 coagulation factor X Homo sapiens 64-67 30259961-6 2018 For FXa inhibitors, a standard heparin-calibrated anti-Xa level of < 0.1 IU.ml-1 should be measured, indicating sufficient reduction in the anticoagulant effect. Heparin 31-38 coagulation factor X Homo sapiens 4-7 30118980-5 2018 As proof of principle, we generated alkyne-modified heparin, immobilized it onto azide-incorporated acellular lungs, and demonstrated its bioactivity by Antithrombin III immobilization and Factor Xa inhibition. Heparin 52-59 coagulation factor X Homo sapiens 189-198 29999301-1 2018 Factor Xa (fXa) inhibition by antithrombin (AT) enabled by heparin or heparan sulfate is critical for controlling blood coagulation. Heparin 59-66 coagulation factor X Homo sapiens 0-9 29999301-1 2018 Factor Xa (fXa) inhibition by antithrombin (AT) enabled by heparin or heparan sulfate is critical for controlling blood coagulation. Heparin 59-66 coagulation factor X Homo sapiens 11-14 29999301-2 2018 AT activation by heparin has been investigated extensively, while interaction of heparin with trapped AT/fXa intermediates has received relatively little attention. Heparin 81-88 coagulation factor X Homo sapiens 105-108 28043992-11 2017 Conclusions: Direct thrombin and FXa inhibitors exhibit distinct effects on assay results when used concomitantly with heparins. Heparin 119-127 coagulation factor X Homo sapiens 33-36 29999301-6 2018 These species are also observed when the trapped intermediate is initially prepared in the presence of a short oligoheparin (dp6), followed by addition of a longer heparin chain (dp20), indicating that binding of heparin to AT/fXa complexes takes place after the inhibition event. Heparin 116-123 coagulation factor X Homo sapiens 227-230 29999301-9 2018 The observed post-inhibition binding of heparin to the trapped AT/fXa intermediates hints at the likely role played by heparan sulfate in their catabolism. Heparin 40-47 coagulation factor X Homo sapiens 66-69 28650000-2 2017 Parenteral anticoagulants with an indirect inhibitory action on FXa (low-molecular-weight heparins) have a well-established clinical efficacy in the prophylaxis and therapy of thromboembolic conditions. Heparin 90-98 coagulation factor X Homo sapiens 64-67 29212374-0 2018 Performance of Anti-Factor Xa Versus Activated Partial Thromboplastin Time for Heparin Monitoring Using Multiple Nomograms. Heparin 79-86 coagulation factor X Homo sapiens 20-29 28862013-0 2018 Influence of Direct Oral Anticoagulants on Anti-Factor Xa Measurements Utilized for Monitoring Heparin. Heparin 95-102 coagulation factor X Homo sapiens 48-57 28862013-1 2018 BACKGROUND: Unanticipated drug-laboratory interactions may occur between direct oral anticoagulants (DOACs) and anti-factor Xa (AXA) levels used to monitor parenteral heparin infusions. Heparin 167-174 coagulation factor X Homo sapiens 117-126 28846877-2 2017 INTRODUCTION: In intensive care unit (ICU) patients, subcutaneous low-molecular weight heparin thromboprophylaxis results in lower plasma anti-factor Xa (anti-FXa) levels compared to general ward patients. Heparin 87-94 coagulation factor X Homo sapiens 159-162 28979172-4 2017 Andexanet alfa is a FXa decoy designed to reverse all anticoagulants that act through this part of the coagulation cascade including anti-FXa DOACs, such as apixaban, edoxaban and rivaroxaban, and indirect FXa inhibitors such as low-molecular-weight heparins. Heparin 250-258 coagulation factor X Homo sapiens 20-23 28486148-4 2017 Furthermore, FXa-cleavable gels enabled a faster release of heparin, which was attributed to the lower affinity of the factor for heparin. Heparin 60-67 coagulation factor X Homo sapiens 13-16 28486148-4 2017 Furthermore, FXa-cleavable gels enabled a faster release of heparin, which was attributed to the lower affinity of the factor for heparin. Heparin 130-137 coagulation factor X Homo sapiens 13-16 28486148-5 2017 Combining early and fast responses, FXa-cleavable gels were shown to provide anticoagulant protection of biomaterial surfaces at low levels of released heparin in human whole-blood incubation experiments. Heparin 152-159 coagulation factor X Homo sapiens 36-39 27917715-4 2017 The direct oral anticoagulants (DOACs) inhibiting factor Xa or thrombin activity represent an alternative for heparins and VKAs. Heparin 110-118 coagulation factor X Homo sapiens 50-59 27301751-0 2016 Blocking inhibition of prothrombinase by tissue factor pathway inhibitor alpha: a procoagulant property of heparins. Heparin 107-115 coagulation factor X Homo sapiens 23-37 27736032-15 2017 However, anti-FXa levels were relatively increased over anti-FIIa levels in infants and after high-dose UFH bolus administration. Heparin 104-107 coagulation factor X Homo sapiens 14-17 27862941-6 2016 It was found (Olson and others) that heparin facilitates the interaction between antithrombin and a clotting enzyme by allosteric changes in the antithrombin (important for factor Xa) and by facilitating the approach of the enzyme to antithrombin via its "sliding" along the heparin molecule (important for thrombin). Heparin 37-44 coagulation factor X Homo sapiens 173-182 27301751-2 2016 UFH prevents tissue factor pathway inhibitor alpha (TFPIalpha) from inhibiting the procoagulant enzyme complex, prothrombinase, providing a possible mechanism for its procoagulant activity. Heparin 0-3 coagulation factor X Homo sapiens 112-126 27412396-2 2016 These inactive ATs were previously proven to effectively neutralise anticoagulant activity associated with heparin derivatives in vitro and in vivo, as assessed by direct measurement of anti-FXa activity. Heparin 107-114 coagulation factor X Homo sapiens 191-194 26876877-10 2016 Factor Xa analysis indicated that the heparin conjugate was still active on the cell surface at 24h post-coating. Heparin 38-45 coagulation factor X Homo sapiens 0-9 25770404-1 2015 OBJECTIVES: This study investigated the relationship between anti-factor Xa (anti-FXa) and activated partial thromboplastin time (aPTT) for monitoring intravenous unfractionated heparin (IV-UFH) in patients with continuous-flow left ventricular assist devices (CF-LVADs). Heparin 178-185 coagulation factor X Homo sapiens 82-85 26607136-12 2016 Direct FXa inhibition by TFPI is modulated by physiological concentrations prothrombin, FV, FVa, protein S, phospholipids and heparin indicating the importance of these modulators for the in vivo anticoagulant activity of TFPI. Heparin 126-133 coagulation factor X Homo sapiens 7-10 26581538-4 2015 We report the case of a woman with chronic kidney disease and a high pretest probability for heparin-induced thrombocytopenia who was acutely treated with apixaban, an oral selective factor Xa inhibitor. Heparin 93-100 coagulation factor X Homo sapiens 183-192 26157187-0 2015 Erratum: Measuring Anti-Factor Xa Activity to Monitor Low-Molecular-Weight Heparin in Obesity: A Critical Review - Correction. Heparin 75-82 coagulation factor X Homo sapiens 24-33 26939028-5 2016 Andexanet alfa is a recombinant modified factor Xa that can bind and reverse oral and parenteral factor Xa inhibitors, including rivaroxaban, apixaban and edoxaban, and low molecular weight heparin. Heparin 190-197 coagulation factor X Homo sapiens 41-50 27067972-3 2016 The therapeutic range of anti-factor Xa activity during therapy with low-molecular weight heparins and danaparoid are less well and of direct oral anticoagulants (DOAC) poorly defined. Heparin 90-98 coagulation factor X Homo sapiens 30-39 26607136-2 2016 Both TFPI and FXa interact with several plasma proteins (e. g. prothrombin, FV/FVa, protein S) and non-proteinaceous compounds (e. g. phospholipids, heparin). Heparin 149-156 coagulation factor X Homo sapiens 14-17 26607136-6 2016 Unfractionated heparin at concentrations (0.2-1 U/ml) enhanced FXa inhibition by TFPI ~8-fold, but impaired inhibition at concentrations > 1 U/ml. Heparin 15-22 coagulation factor X Homo sapiens 63-66 26733269-0 2015 The Anti-Factor Xa Range For Low Molecular Weight Heparin Thromboprophylaxis. Heparin 50-57 coagulation factor X Homo sapiens 9-18 25855705-4 2015 OBJECTIVE: To determine whether FDA-approved commercial kits for measuring heparin anti-factor Xa activity can be used to assess rivaroxaban concentrations when calibrated for unfractionated heparin or low-molecular-weight heparins. Heparin 75-82 coagulation factor X Homo sapiens 88-97 25832311-3 2015 Especially the oral direct FXa and FIIa inhibitors overcome many of the shortcomings of heparins and vitamin K antagonists (VKAs). Heparin 88-96 coagulation factor X Homo sapiens 27-30 25770404-14 2015 Use of aPTT and anti-FXa to guide heparin therapy may lead to different estimates of heparin concentration in the same patient. Heparin 34-41 coagulation factor X Homo sapiens 21-24 25770404-14 2015 Use of aPTT and anti-FXa to guide heparin therapy may lead to different estimates of heparin concentration in the same patient. Heparin 85-92 coagulation factor X Homo sapiens 21-24 24561026-6 2014 Here we present the isolation and identification of an octadecasaccharide with very high anti-factor Xa activity (~3 times higher than USP [U.S. Pharmacopeia] heparin). Heparin 159-166 coagulation factor X Homo sapiens 94-103 25377080-1 2014 The factor Xa inhibitor apixaban is one of the novel anticoagulants to emerge as alternatives to long-standing standards of care that include low-molecular-weight heparin and warfarin. Heparin 163-170 coagulation factor X Homo sapiens 4-13 25242245-0 2014 Sulfated low molecular weight lignins, allosteric inhibitors of coagulation proteinases via the heparin binding site, significantly alter the active site of thrombin and factor xa compared to heparin. Heparin 96-103 coagulation factor X Homo sapiens 170-179 25248688-5 2014 In contrast, aPTT was significantly shorter and anti-FXa activity was significantly lower in partial-draw than in full-draw tubes collected from 46 patients receiving unfractionated heparin (UFH). Heparin 191-194 coagulation factor X Homo sapiens 53-56 24561026-1 2014 Heparin and low-molecular-weight heparins (LMWHs) are anticoagulant drugs that mainly inhibit the coagulation cascade by indirectly interacting with factor Xa and factor IIa (thrombin). Heparin 0-7 coagulation factor X Homo sapiens 149-173 25463496-8 2015 The efficacy of heparin linkage was demonstrated with factor Xa anti-thrombogenic assay and platelet adhesion studies. Heparin 16-23 coagulation factor X Homo sapiens 54-63 25526009-1 2014 Enoxaparin sodium is a heparin of low molecular weight with antithrombotic properties that acts by inhibiting factor Xa. Heparin 23-30 coagulation factor X Homo sapiens 110-119 24561026-1 2014 Heparin and low-molecular-weight heparins (LMWHs) are anticoagulant drugs that mainly inhibit the coagulation cascade by indirectly interacting with factor Xa and factor IIa (thrombin). Heparin 33-41 coagulation factor X Homo sapiens 149-173 24616065-1 2014 The anticoagulant properties of heparin stem in part from high-affinity binding to antithrombin-III (AT-III) inducing a 300-fold increase in its inhibitory activity against the coagulation protease factor Xa. Heparin 32-39 coagulation factor X Homo sapiens 198-207 24650612-3 2014 Nowadays, four new inhibitors of factor Xa are used orally (rivaroxaban, apixaban, edoxaban, betrixaban), and they are at least as efficient as heparins and vitamin K antagonists. Heparin 144-152 coagulation factor X Homo sapiens 33-42 24650612-4 2014 The objective is to substitute these indirect inhibitors of factor Xa (heparins, low molecular weight heparins and fondaparinux) in the prevention of venous and arterial thromboembolic episodes. Heparin 71-79 coagulation factor X Homo sapiens 60-69 24650612-4 2014 The objective is to substitute these indirect inhibitors of factor Xa (heparins, low molecular weight heparins and fondaparinux) in the prevention of venous and arterial thromboembolic episodes. Heparin 102-110 coagulation factor X Homo sapiens 60-69 24647152-3 2014 Therefore, low molecular weight heparins (LMWHs) and ultra low molecular weight heparins (ULMWHs), with lower molecular weights, higher anti-FXa activity, longer half-life times and lower incidence of adverse events than unfractionated heparin (UFH), were researched and developed. Heparin 32-40 coagulation factor X Homo sapiens 141-144 24388571-9 2014 Anti-FXa activity reduced on the start of CPB compared to the level after heparinization, to almost the baseline value following protamine reversal of heparin. Heparin 74-81 coagulation factor X Homo sapiens 5-8 24678194-0 2014 Elucidating the specificity of non-heparin-based conformational activators of antithrombin for factor Xa inhibition. Heparin 35-42 coagulation factor X Homo sapiens 95-104 24335992-0 2014 Anti-factor Xa assay is a superior correlate of heparin dose than activated partial thromboplastin time or activated clotting time in pediatric extracorporeal membrane oxygenation*. Heparin 48-55 coagulation factor X Homo sapiens 5-14 24335992-12 2014 CONCLUSIONS: The anti-Factor Xa assay correlated better with heparin dosing than activated clotting time or activated partial thromboplastin time. Heparin 61-68 coagulation factor X Homo sapiens 22-31 24335992-14 2014 In pediatric extracorporeal membrane oxygenation, anti-Factor Xa assay may be a more valuable monitor of heparin administration. Heparin 105-112 coagulation factor X Homo sapiens 55-64 24124146-9 2013 CONCLUSIONS: Anti-FXa antithrombin assay is recommended as a first-line test to detect type II heparin-binding site antithrombin deficiency. Heparin 95-102 coagulation factor X Homo sapiens 18-21 24357866-0 2013 Effectiveness of Unfractionated Heparin in Normal Saline versus Dextrose for Achieving and Maintaining Therapeutic Anti-Factor Xa Levels in Patients with Non-ST-Elevation Acute Coronary Syndrome. Heparin 32-39 coagulation factor X Homo sapiens 120-129 24095600-2 2013 The anticoagulation process is mainly caused by the interaction of heparin with antithrombin followed by inhibition of anticoagulant factor IIa and factor Xa. Heparin 67-74 coagulation factor X Homo sapiens 148-157 24357866-4 2013 OBJECTIVE: To compare the effectiveness of UFH-NS and UFH-D5W for achieving and maintaining therapeutic anti-factor Xa levels in patients with non-ST-elevation acute coronary syndrome. Heparin 43-46 coagulation factor X Homo sapiens 109-118 23990470-9 2013 As a consequence, heparin-catalyzed inhibition of factor Xa by antithrombin is compromised by fibrinogen to a greater extent when Zn(2+) is present. Heparin 18-25 coagulation factor X Homo sapiens 50-59 22518847-1 2012 Factor-Xa assembly into the prothrombinase complex decreases its availability for inhibition by antithrombin + unfractionated heparin (AT + UFH). Heparin 126-133 coagulation factor X Homo sapiens 0-9 23494009-0 2013 Covalently linking heparin to antithrombin enhances prothrombinase inhibition on activated platelets. Heparin 19-26 coagulation factor X Homo sapiens 52-66 23494009-1 2013 Factor (F)Xa within the prothrombinase complex is protected from inhibition by unfractionated heparin (UFH), enoxaparin and fondaparinux. Heparin 94-101 coagulation factor X Homo sapiens 24-38 23494009-1 2013 Factor (F)Xa within the prothrombinase complex is protected from inhibition by unfractionated heparin (UFH), enoxaparin and fondaparinux. Heparin 103-106 coagulation factor X Homo sapiens 24-38 23641666-8 2013 The efficacy of selected peptoids as agents for neutralization of the anticoagulant activity of heparin was assayed by the Coatest method, which measures restoration of the activity of the serine protease factor Xa (FXa). Heparin 96-103 coagulation factor X Homo sapiens 216-219 22773834-2 2012 Heparin is a commonly used anticoagulant drug that inhibits the activities of factors Xa and IIa (also known as thrombin) to prevent blood clot formation. Heparin 0-7 coagulation factor X Homo sapiens 78-96 22920489-4 2012 Unfractionated heparin traditionally has been the most commonly used anticoagulant but is fast being replaced by relatively newer agents like LMWH, direct thrombin inhibitors, and Factor Xa inhibitors. Heparin 15-22 coagulation factor X Homo sapiens 180-189 23627997-7 2013 MEASUREMENTS AND MAIN RESULTS: Plasma heparin expressed as anti-FXa activity was detected in 180 (88%) samples. Heparin 38-45 coagulation factor X Homo sapiens 64-67 24164039-0 2013 [An assay for anti-factor Xa activity of low molecular weight heparins by high performance liquid size exclusion chromatography]. Heparin 62-70 coagulation factor X Homo sapiens 19-28 23227470-2 2012 Critically ill patients have significantly lower plasma anti-factor-Xa activity levels compared with control patients after administration of subcutaneous heparin. Heparin 155-162 coagulation factor X Homo sapiens 61-70 23227470-3 2012 The clinical relevance of the different anti-factor-Xa levels after prophylactic doses of low molecular weight heparin (LMWH) in critically ill patients is not completely understood. Heparin 111-118 coagulation factor X Homo sapiens 45-54 22518847-1 2012 Factor-Xa assembly into the prothrombinase complex decreases its availability for inhibition by antithrombin + unfractionated heparin (AT + UFH). Heparin 126-133 coagulation factor X Homo sapiens 28-42 22518847-11 2012 Overall, the results suggest that covalent linkage between AT-heparin assists access and neutralization of complexed Xa, with concomitant inhibition of prothrombinase function compared with conventional non-conjugated heparin. Heparin 62-69 coagulation factor X Homo sapiens 152-166 22231174-0 2012 Standard subcutaneous dosing of unfractionated heparin for venous thromboembolism prophylaxis in surgical ICU patients leads to subtherapeutic factor Xa inhibition. Heparin 47-54 coagulation factor X Homo sapiens 143-152 22453684-4 2012 The conformational activation of antithrombin by heparin is a critical step in the inhibition of factor Xa by antithrombin. Heparin 49-56 coagulation factor X Homo sapiens 97-106 22453684-5 2012 Despite heparin being the most potent physiological activator which enhances the otherwise very lethargic antithrombin inhibition of factor Xa by approximately 1,000-fold, the conventional heparin therapy poses serious complications because of heparin"s polyanionic nature and its cross-reactivity. Heparin 8-15 coagulation factor X Homo sapiens 133-142 22453684-6 2012 A number of attempts have been carried out in designing alternative non-heparin based conformational activators of antithrombin for factor Xa inhibition. Heparin 72-79 coagulation factor X Homo sapiens 132-141 22540147-1 2012 High-molecular weight heparins promote the protein Z-dependent protease inhibitor (ZPI) inhibition of factors Xa (FXa) and XIa (FXIa) by a template mechanism. Heparin 22-30 coagulation factor X Homo sapiens 114-117 22540147-5 2012 By contrast, the mutants interacted with heparin with a lower affinity and the ~48-fold heparin-mediated enhancement in the rate of FXa inhibition by ZPI was reduced to ~30-fold for ZPI-3A, ~15-fold for ZPI-D-helix(alpha1-PI), and ~8-fold for ZPI-CD-helix(alpha1-PI). Heparin 41-48 coagulation factor X Homo sapiens 132-135 22540147-5 2012 By contrast, the mutants interacted with heparin with a lower affinity and the ~48-fold heparin-mediated enhancement in the rate of FXa inhibition by ZPI was reduced to ~30-fold for ZPI-3A, ~15-fold for ZPI-D-helix(alpha1-PI), and ~8-fold for ZPI-CD-helix(alpha1-PI). Heparin 88-95 coagulation factor X Homo sapiens 132-135 22231174-12 2012 CONCLUSIONS: Standard of care subcutaneous dosing of unfractionated heparin for VTE prophylaxis in surgical ICU patients leads to subtherapeutic levels of factor Xa inhibition. Heparin 68-75 coagulation factor X Homo sapiens 155-164 22089943-0 2012 Effects of four commercially available factor Xa proteins on the fluorogenic anti-factor Xa assay when monitoring unfractionated heparin. Heparin 129-136 coagulation factor X Homo sapiens 82-91 22081368-4 2012 The recently developed direct factor Xa inhibitors (the xabans) appear to offer promise as alternatives to the heparins. Heparin 111-119 coagulation factor X Homo sapiens 30-39 22315264-3 2012 UFH is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a unique pentasaccharide sequence and catalyze the inactivation of thrombin, factor Xa, and other clotting enzymes. Heparin 0-3 coagulation factor X Homo sapiens 160-169 21220249-5 2011 Like heparin, thrombin and FXa cause an increase in IGF-I in ESCs, suggesting an action of heparin independent from its anticoagulatory effects. Heparin 91-98 coagulation factor X Homo sapiens 27-30 21852056-0 2011 Quantification of unfractionated heparin in human plasma and whole blood by means of novel fluorogenic anti-FXa assays. Heparin 33-40 coagulation factor X Homo sapiens 108-111 21852056-1 2011 Novel and sensitive plate-based fluorogenic anti-factor Xa (FXa) assays were investigated to quantify unfractionated heparin (UFH) in human plasma and whole blood within the therapeutic ranges of 0-1.6 U/mL and 0-0.8 U/mL, respectively. Heparin 117-124 coagulation factor X Homo sapiens 60-63 21852056-2 2011 Two fluorogenic anti-FXa assay methods were defined for low (0-0.6 U/mL) and high (0.6-1.2 U/mL) pharmacologically relevant UFH concentration ranges in pooled human plasma. Heparin 124-127 coagulation factor X Homo sapiens 21-24 22012070-5 2011 In this assay, direct factor Xa (FXa) inhibitors such as edoxaban and antithrombin (AT)-dependent anticoagulants such as heparin did not increase, but simply suppressed TG. Heparin 121-128 coagulation factor X Homo sapiens 22-31 22012070-5 2011 In this assay, direct factor Xa (FXa) inhibitors such as edoxaban and antithrombin (AT)-dependent anticoagulants such as heparin did not increase, but simply suppressed TG. Heparin 121-128 coagulation factor X Homo sapiens 33-36 21880887-2 2011 SUMMARY: The administration of low-molecular-weight heparins to obese patients (body mass index [BMI] of >=30 kg/m(2)) at the dose recommended for VTE prophylaxis has been reported to result in increased thromboembolic events and decreased anti-factor Xa levels, and some evidence indicates that weight-based dosing adjustments may be appropriate. Heparin 52-60 coagulation factor X Homo sapiens 248-257 21538828-5 2011 The surface exhibited anti factor Xa activity, thus confirming the presence of bounded heparin that kept some biological activity. Heparin 87-94 coagulation factor X Homo sapiens 27-36 21401902-9 2011 Factor Xa based assays may be particularly sensitive to certain heparin binding defects, and sensitivity of assays to both heparin binding and reactive site defects can be improved by shortening the incubation time with enzyme. Heparin 64-71 coagulation factor X Homo sapiens 0-9 21740405-1 2012 New direct and indirect acting factor Xa (FXa) and thrombin inhibitors are being developed to overcome the downsides of the conventional anticoagulants - unfractionated and low molecular weight heparins and vitamin K antagonists. Heparin 194-202 coagulation factor X Homo sapiens 31-40 21740405-1 2012 New direct and indirect acting factor Xa (FXa) and thrombin inhibitors are being developed to overcome the downsides of the conventional anticoagulants - unfractionated and low molecular weight heparins and vitamin K antagonists. Heparin 194-202 coagulation factor X Homo sapiens 42-45 22174307-1 2011 In this issue of Blood, Yau and colleagues provide evidence that guide catheter thrombosis in patients undergoing percutaneous coronary intervention (PCI) is initiated by contact system activation, and that unfractionated heparin is more effective than fondaparinux at limiting catheter occlusions because heparin-antithrombin complexes are able to target multiple points along the coagulation cascade, as opposed to the smaller fractionated heparins and heparinoids that provide higher selectivity for factor Xa. Heparin 222-229 coagulation factor X Homo sapiens 503-512 21872908-10 2011 RESULTS: The fluorogenic anti-FXa assay was found to have the broadest therapeutic range of 0-1 U/ml with CVs of<5% for UFH and tinzaparin and CVs<9% for enoxaparin. Heparin 123-126 coagulation factor X Homo sapiens 30-33 21767328-11 2011 Only 28% of the 32 cases treated with low molecular weight heparin titrated dosing to a goal anti-FXa level 0.5-1. Heparin 59-66 coagulation factor X Homo sapiens 98-101 20953779-0 2011 Combination of a two-step fluorescence assay and a two-step anti-Factor Xa assay for detection of heparin falsifications and protein in heparins. Heparin 98-105 coagulation factor X Homo sapiens 65-74 21220417-3 2011 Heparin produced 20-100-fold accelerations of ZPI reactions with factor Xa and factor XIa to yield second order rate constants approaching the physiologically significant diffusion limit (k(a) = 10(6) to 10(7) M(-1) s(-1)). Heparin 0-7 coagulation factor X Homo sapiens 65-74 21220417-5 2011 Maximal accelerations of ZPI-factor Xa reactions required calcium, which augmented the heparin acceleration by relieving Gla domain inhibition as previously shown for heparin bridging of the antithrombin-factor Xa reaction. Heparin 87-94 coagulation factor X Homo sapiens 29-38 21220417-5 2011 Maximal accelerations of ZPI-factor Xa reactions required calcium, which augmented the heparin acceleration by relieving Gla domain inhibition as previously shown for heparin bridging of the antithrombin-factor Xa reaction. Heparin 87-94 coagulation factor X Homo sapiens 204-213 21220417-8 2011 Taken together, these results suggest that whereas protein Z, lipid, and calcium cofactors promote ZPI inhibition of membrane-associated factor Xa, heparin activates ZPI to inhibit free factor Xa as well as factor XIa and therefore may play a physiologically and pharmacologically important role in ZPI anticoagulant function. Heparin 148-155 coagulation factor X Homo sapiens 186-195 21086021-1 2011 Heparin compounds, to include fractionated and unfractionated preparations, exert both antithrombotic and antiinflammatory effects through combined inhibition of factor Xa and thrombin. Heparin 0-7 coagulation factor X Homo sapiens 162-171 21086021-9 2011 The ability of heparin compounds to affect the prothrombotic and proinflammatory states which characterize ACS may involve factor Xa-related modulation of platelet activation and expression. Heparin 15-22 coagulation factor X Homo sapiens 123-132 20953779-0 2011 Combination of a two-step fluorescence assay and a two-step anti-Factor Xa assay for detection of heparin falsifications and protein in heparins. Heparin 136-144 coagulation factor X Homo sapiens 65-74 20847691-4 2010 RECENT FINDINGS: Oral administration, predictable anticoagulant responses, low potential for drug-drug interactions render direct thrombin and factor Xa inhibitors good candidates to replace UFH, LMWH and fondaparinux for VTE prophylaxis. Heparin 191-194 coagulation factor X Homo sapiens 143-152 22013445-6 2011 Factor-specific anticoagulants have been proven safe and effective, and recently factor Xa inhibitors have emerged as a treatment alternative to heparins and VKA. Heparin 145-153 coagulation factor X Homo sapiens 81-90 21150227-0 2011 Effects of nadroparin, enoxaparin, and unfractionated heparin on endogenous formation of factor Xa and IIa and on thrombelastometry profiles in cord versus adult blood. Heparin 54-61 coagulation factor X Homo sapiens 89-98 21150227-4 2011 METHODS: The effects of nadroparin, enoxaparin, or UH on endogenous formation of FXa or FIIa was investigated in tissue factor-activated PPP using a subsampling technique and chromogenic substrates. Heparin 51-53 coagulation factor X Homo sapiens 81-84 20441964-2 2010 A fluorogenic anti-factor Xa (anti-FXa) assay has been developed for the determination of unfractionated heparin (UFH), low molecular weight heparins (LMWHs), namely enoxaparin and tinzaparin, and the synthetic heparinoid danaparoid, in commercial human pooled plasma. Heparin 105-112 coagulation factor X Homo sapiens 35-38 20950840-5 2010 In patients on unfractionated heparin (UFH), significantly lower anti-FXa activity [median=0.29IU/mL (range:0.04-1.15) vs. 0.39 (0.05-1.25), n=89, p<0.0001] and shorter aPTT were measured in partial-draw tubes. Heparin 30-37 coagulation factor X Homo sapiens 70-73 20950840-5 2010 In patients on unfractionated heparin (UFH), significantly lower anti-FXa activity [median=0.29IU/mL (range:0.04-1.15) vs. 0.39 (0.05-1.25), n=89, p<0.0001] and shorter aPTT were measured in partial-draw tubes. Heparin 39-42 coagulation factor X Homo sapiens 70-73 20628058-1 2010 The activation of antithrombin (AT) by heparin facilitates the exosite-dependent interaction of the serpin with factors IXa (FIXa) and Xa (FXa), thereby improving the rate of reactions by 300- to 500-fold. Heparin 39-46 coagulation factor X Homo sapiens 139-142 20524194-2 2010 End-thiolated heparin retained anticoagulant activity as shown by the activated partial thromboplastin time (aPTT) and anti-Factor Xa (anti-FXa) assays. Heparin 14-21 coagulation factor X Homo sapiens 124-133 20524194-2 2010 End-thiolated heparin retained anticoagulant activity as shown by the activated partial thromboplastin time (aPTT) and anti-Factor Xa (anti-FXa) assays. Heparin 14-21 coagulation factor X Homo sapiens 140-143 20524194-6 2010 However, immobilized heparin retained substantial anti-FXa activity, with significantly greater activity exhibited by the end-thiolated HepNH(2) than the internally (randomly) thiolated UFH. Heparin 21-28 coagulation factor X Homo sapiens 55-58 20441964-2 2010 A fluorogenic anti-factor Xa (anti-FXa) assay has been developed for the determination of unfractionated heparin (UFH), low molecular weight heparins (LMWHs), namely enoxaparin and tinzaparin, and the synthetic heparinoid danaparoid, in commercial human pooled plasma. Heparin 114-117 coagulation factor X Homo sapiens 35-38 20441964-2 2010 A fluorogenic anti-factor Xa (anti-FXa) assay has been developed for the determination of unfractionated heparin (UFH), low molecular weight heparins (LMWHs), namely enoxaparin and tinzaparin, and the synthetic heparinoid danaparoid, in commercial human pooled plasma. Heparin 141-149 coagulation factor X Homo sapiens 35-38 20441964-3 2010 The assay was based on the complexation of heparin-spiked plasmas with exogenous FXa at a concentration of 4nM in the presence of 0.9microM of the fluorogenic substrate methylsulfonyl-D-cyclohexylalanyl-glycyl-arginine-7-amino-4-methylcoumarin acetate (Pefafluor FXa). Heparin 43-50 coagulation factor X Homo sapiens 81-84 20441964-3 2010 The assay was based on the complexation of heparin-spiked plasmas with exogenous FXa at a concentration of 4nM in the presence of 0.9microM of the fluorogenic substrate methylsulfonyl-D-cyclohexylalanyl-glycyl-arginine-7-amino-4-methylcoumarin acetate (Pefafluor FXa). Heparin 43-50 coagulation factor X Homo sapiens 263-266 20024502-1 2010 Heparin promotes the antithrombin (AT) inactivation of factors IXa (fIXa) and Xa (fXa) through a conformational activation of the serpin and also by a template mechanism in the presence of physiological levels of Ca2+. Heparin 0-7 coagulation factor X Homo sapiens 82-85 20402553-7 2010 TAKE HOME MESSAGE: Oral administration, predictable anticoagulant responses, low potential for drug-drug interactions and first published clinical data render direct thrombin and factor Xa inhibitors good candidates to replace oral vitamin K antagonist and low molecular weight heparins for DVT treatment. Heparin 278-286 coagulation factor X Homo sapiens 179-188 20368520-2 2010 M118 is a novel low-molecular-weight heparin that has been rationally designed to capture the desired attributes of unfractionated heparin (UFH) and low-molecular-weight heparin: Potent activity against factor Xa and IIa, predictable pharmacokinetics after both intravenous and subcutaneous administration, ability to be monitored by use of point-of-care coagulation assays, and reversibility with protamine sulfate. Heparin 37-44 coagulation factor X Homo sapiens 203-212 20024502-2 2010 Recently, it was reported that heparin induces conformational changes in the active-sites of fIXa and fXa, raising the possibility that heparin also modulates the reactivity of these proteases with AT by this mechanism. Heparin 31-38 coagulation factor X Homo sapiens 102-105 20024502-2 2010 Recently, it was reported that heparin induces conformational changes in the active-sites of fIXa and fXa, raising the possibility that heparin also modulates the reactivity of these proteases with AT by this mechanism. Heparin 136-143 coagulation factor X Homo sapiens 102-105 20024502-6 2010 Full-length heparin-concentration dependence of the AT inhibition of fIXa and fXa revealed that in contrast to a greater than 4-5 orders of magnitude accelerating effect for heparin on the AT inhibition of fIXa and fXa, heparin exhibits a negligible cofactor effect (<2-fold) on the mutant AT inhibition of these proteases. Heparin 12-19 coagulation factor X Homo sapiens 78-81 19150337-6 2009 These findings suggest that PF4 in the presence of heparin is an allosteric effector of the prothrombinase complex. Heparin 51-58 coagulation factor X Homo sapiens 92-106 20423535-2 2010 Several studies show that critically ill patients have significantly lower plasma anti-factor-Xa activity levels compared to control patients after administration of subcutaneous heparin. Heparin 179-186 coagulation factor X Homo sapiens 87-96 19967150-7 2009 We show that sulfated galactan interacts with the heparin-binding exosite of FXa and Arg-236 and Lys-240 of this site are critical residues for this interaction, as observed for heparin. Heparin 50-57 coagulation factor X Homo sapiens 77-80 19967150-7 2009 We show that sulfated galactan interacts with the heparin-binding exosite of FXa and Arg-236 and Lys-240 of this site are critical residues for this interaction, as observed for heparin. Heparin 178-185 coagulation factor X Homo sapiens 77-80 19967150-8 2009 Thus, sulfated galactan and heparin have similar high-affinity and specificity for interaction with FXa, though they have differences in their chemical structures. Heparin 28-35 coagulation factor X Homo sapiens 100-103 18996625-1 2009 Antithrombin, a plasma glycoprotein serpin, requires conformational activation by heparin to induce an anticoagulant effect, which is mediated through accelerated factor Xa inhibition. Heparin 82-89 coagulation factor X Homo sapiens 163-172 19543696-1 2009 Unfractionated heparin (UFH) enhances antithrombin (AT) inhibition of thrombin (IIa) and factor Xa (FXa). Heparin 15-22 coagulation factor X Homo sapiens 89-98 19543696-1 2009 Unfractionated heparin (UFH) enhances antithrombin (AT) inhibition of thrombin (IIa) and factor Xa (FXa). Heparin 15-22 coagulation factor X Homo sapiens 100-103 19543696-1 2009 Unfractionated heparin (UFH) enhances antithrombin (AT) inhibition of thrombin (IIa) and factor Xa (FXa). Heparin 24-27 coagulation factor X Homo sapiens 89-98 19543696-1 2009 Unfractionated heparin (UFH) enhances antithrombin (AT) inhibition of thrombin (IIa) and factor Xa (FXa). Heparin 24-27 coagulation factor X Homo sapiens 100-103 19543696-2 2009 Low molecular weight heparins (LMWH) primarily enhance AT inhibition of FXa. Heparin 21-29 coagulation factor X Homo sapiens 72-75 19195682-1 2009 Low-molecular-weight heparins (LMWH) exert their anticoagulant effect by accelerating anti-thrombin (AT) inactivation of factor Xa (fXa) and thrombin. Heparin 21-29 coagulation factor X Homo sapiens 121-130 19195682-1 2009 Low-molecular-weight heparins (LMWH) exert their anticoagulant effect by accelerating anti-thrombin (AT) inactivation of factor Xa (fXa) and thrombin. Heparin 21-29 coagulation factor X Homo sapiens 132-135 19010776-1 2009 We have previously shown that residues Tyr-253 and Glu-255 in the serpin antithrombin function as exosites to promote the inhibition of factor Xa and factor IXa when the serpin is conformationally activated by heparin. Heparin 210-217 coagulation factor X Homo sapiens 136-160 19140680-0 2009 Heparin enhances the inhibition of factor Xa by protein C inhibitor in the presence but not in the absence of Ca2+. Heparin 0-7 coagulation factor X Homo sapiens 35-44 19140680-3 2009 In this study, heparin was found to enhance PCI inhibition of factor Xa up to 42-fold in the presence of a physiological Ca(2+) concentration, whereas no heparin-induced activation was observed in the absence of Ca(2+). Heparin 15-22 coagulation factor X Homo sapiens 62-71 19140680-4 2009 These results thus show that factor Xa adds to the group of proteases whose inhibition by PCI is enhanced by heparin and that such inhibition contributes to the anticoagulant properties of PCI by a Ca(2+)-dependent mechanism. Heparin 109-116 coagulation factor X Homo sapiens 29-38 18045667-6 2008 CONCLUSION: The data fit a model in which thrombin and factor Xa bind at a random site on the heparin chain and, via one-dimensional diffusion, reach the AT that is bound to its specific binding site on the heparin. Heparin 94-101 coagulation factor X Homo sapiens 55-64 18574264-2 2008 UFH is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a unique pentasaccharide sequence and catalyze the inactivation of thrombin factor Xa and other clotting factors. Heparin 0-3 coagulation factor X Homo sapiens 159-168 17996279-4 2008 Low-molecular-weight heparins are fragments of unfractionated heparin produced by controlled enzymatic or chemical depolymerization processes with the main difference being in their relative inhibitory activity against factor Xa and thrombin. Heparin 21-29 coagulation factor X Homo sapiens 219-228 17996279-4 2008 Low-molecular-weight heparins are fragments of unfractionated heparin produced by controlled enzymatic or chemical depolymerization processes with the main difference being in their relative inhibitory activity against factor Xa and thrombin. Heparin 21-28 coagulation factor X Homo sapiens 219-228 20339323-0 2009 Effects of nadroparin, enoxaparin, and unfractionated heparin on endogenous factor Xa and IIa formation and on thrombelastometry profiles. Heparin 54-61 coagulation factor X Homo sapiens 76-85 20339323-1 2009 Measurements of anti-FXa or anti-FIIa (thrombin) activities are conventional tests for biological monitoring of low molecular weight heparin (LMWH) or unfractionated heparin treatment. Heparin 133-140 coagulation factor X Homo sapiens 21-24 20339323-3 2009 The effects of increasing amounts of nadroparin, enoxaparin, or unfractionated heparin on the time-course of FXa or FIIa formation were investigated in tissue factor activated platelet-poor plasma using a subsampling technique and chromogenic substrates. Heparin 79-86 coagulation factor X Homo sapiens 109-112 20339323-7 2009 Compared with equivalent anti-FXa activity, unfractionated heparin is markedly more efficient in suppressing the formation of FXa and FIIa than the LMWHs. Heparin 59-66 coagulation factor X Homo sapiens 126-129 18574281-6 2008 Dosing of IV UFH should prolong the activated partial thromboplastin time (aPTT) to a range that corresponds to an anti-factor Xa assay (anti-FXa) level of 0.35 to 0.7 U/mL, whereas LMWH should achieve an anti-FXa level of 0.5 to 1.0 U/mL 4 h after an injection for twice-daily dosing. Heparin 13-16 coagulation factor X Homo sapiens 142-145 18574281-6 2008 Dosing of IV UFH should prolong the activated partial thromboplastin time (aPTT) to a range that corresponds to an anti-factor Xa assay (anti-FXa) level of 0.35 to 0.7 U/mL, whereas LMWH should achieve an anti-FXa level of 0.5 to 1.0 U/mL 4 h after an injection for twice-daily dosing. Heparin 13-16 coagulation factor X Homo sapiens 210-213 18042685-2 2008 In contrast to human TFPI, Ixolaris specifically binds to factor Xa (FXa) heparin-binding exosite (HBE). Heparin 74-81 coagulation factor X Homo sapiens 58-67 18042685-2 2008 In contrast to human TFPI, Ixolaris specifically binds to factor Xa (FXa) heparin-binding exosite (HBE). Heparin 74-81 coagulation factor X Homo sapiens 69-72 18045667-0 2008 Linear diffusion of thrombin and factor Xa along the heparin molecule explains the effects of extended heparin chain lengths. Heparin 53-60 coagulation factor X Homo sapiens 33-42 18045667-0 2008 Linear diffusion of thrombin and factor Xa along the heparin molecule explains the effects of extended heparin chain lengths. Heparin 103-110 coagulation factor X Homo sapiens 33-42 18045667-3 2008 RESULTS: The Kd of thrombin or factor Xa is constant when expressed in terms of the concentration of sugar units, i.e. the enzymes bind the better the longer the heparin. Heparin 162-169 coagulation factor X Homo sapiens 31-40 18045667-6 2008 CONCLUSION: The data fit a model in which thrombin and factor Xa bind at a random site on the heparin chain and, via one-dimensional diffusion, reach the AT that is bound to its specific binding site on the heparin. Heparin 207-214 coagulation factor X Homo sapiens 55-64 18060241-4 2007 The low molecular weight heparins (LMWH) show favourable pharmacokinetics over UFH and have a more pronounced activity against factor Xa as opposed to thrombin which may partially account for the benefits observed with LMWH in clinical trials. Heparin 25-33 coagulation factor X Homo sapiens 127-136 17629847-1 2007 Prothrombinase-induced clotting time (PiCT) determines the anticoagulant effects of heparins, low molecular weight heparins (LMWHs), and direct thrombin inhibitors. Heparin 84-92 coagulation factor X Homo sapiens 0-14 17874721-0 2007 [Determination of factor Xa inhibition doses of low-molecular heparin, nadroparin and reviparin in urological patients]. Heparin 62-69 coagulation factor X Homo sapiens 18-27 17874721-1 2007 BACKGROUND/AIM: The inhibition of factor Xa (FX) by the use of low-molecular heparin (LMH) is important clinical procedure in patients with moderate and high risk for the development of venous thromboembolism (VTE) and pulmonary embolism (PE). Heparin 77-84 coagulation factor X Homo sapiens 34-43 17629847-1 2007 Prothrombinase-induced clotting time (PiCT) determines the anticoagulant effects of heparins, low molecular weight heparins (LMWHs), and direct thrombin inhibitors. Heparin 115-123 coagulation factor X Homo sapiens 0-14 17489664-1 2007 Enoxaparin is a low-molecular-weight heparin (LMWH) derivative that exerts its anticoagulant activity through antithrombin III, an endogenous inhibitor of factor Xa and thrombin IIa. Heparin 37-44 coagulation factor X Homo sapiens 155-164 17672188-0 2007 Heparin monitoring during cardiopulmonary bypass surgery using the one-step point-of-care whole blood anti-factor-Xa clotting assay heptest-POC-Hi. Heparin 0-7 coagulation factor X Homo sapiens 107-116 18023704-13 2007 In addition, pro-heparanase can reverse the anti-coagulant effect of unfractionated heparin and the Factor Xa inhibitory activity of low molecular weight heparin (LMWH). Heparin 154-161 coagulation factor X Homo sapiens 100-109 17380210-3 2007 By inhibiting both free and clot-bound factor Xa complexes, the oral factor Xa inhibitors prolong activated partial thromboplastin time and prothrombin times in a dose-dependent manner without the need for antithrombin, thus differing from drugs such as fondaparinux, heparin, etc. Heparin 268-275 coagulation factor X Homo sapiens 39-48 17380210-3 2007 By inhibiting both free and clot-bound factor Xa complexes, the oral factor Xa inhibitors prolong activated partial thromboplastin time and prothrombin times in a dose-dependent manner without the need for antithrombin, thus differing from drugs such as fondaparinux, heparin, etc. Heparin 268-275 coagulation factor X Homo sapiens 69-78 16515805-0 2007 Heparin chain-length dependence of factor Xa inhibition by antithrombin in plasma. Heparin 0-7 coagulation factor X Homo sapiens 35-44 16515805-2 2007 A direct evaluation of the specific anti-factor Xa (fXa) activity of therapeutic heparins in the physiologically relevant plasma-based clotting assays has not been feasible since thrombin, the final protease of the cascade, is the primary target for inhibition by AT in the presence of heparin. Heparin 81-89 coagulation factor X Homo sapiens 41-50 16515805-2 2007 A direct evaluation of the specific anti-factor Xa (fXa) activity of therapeutic heparins in the physiologically relevant plasma-based clotting assays has not been feasible since thrombin, the final protease of the cascade, is the primary target for inhibition by AT in the presence of heparin. Heparin 81-89 coagulation factor X Homo sapiens 52-55 16515805-2 2007 A direct evaluation of the specific anti-factor Xa (fXa) activity of therapeutic heparins in the physiologically relevant plasma-based clotting assays has not been feasible since thrombin, the final protease of the cascade, is the primary target for inhibition by AT in the presence of heparin. Heparin 81-88 coagulation factor X Homo sapiens 41-50 16515805-2 2007 A direct evaluation of the specific anti-factor Xa (fXa) activity of therapeutic heparins in the physiologically relevant plasma-based clotting assays has not been feasible since thrombin, the final protease of the cascade, is the primary target for inhibition by AT in the presence of heparin. Heparin 81-88 coagulation factor X Homo sapiens 52-55 16515805-4 2007 This assay was used to distinguish the anti-fXa activity of different molecular weight heparins from their anti-thrombin activity in clotting assays which were initiated by the triggers of either the extrinsic or intrinsic coagulation pathway. Heparin 87-95 coagulation factor X Homo sapiens 44-47 16515805-5 2007 The results suggest that the acceleration of fXa inhibition by AT exhibits a marked heparin chain-length dependence, with fondaparinux (a pentasaccharide) having the lowest and unfractionated heparin having the highest effect. Heparin 84-91 coagulation factor X Homo sapiens 45-48 16515805-5 2007 The results suggest that the acceleration of fXa inhibition by AT exhibits a marked heparin chain-length dependence, with fondaparinux (a pentasaccharide) having the lowest and unfractionated heparin having the highest effect. Heparin 192-199 coagulation factor X Homo sapiens 45-48 17461929-1 2007 BACKGROUND: Low-molecular-weight heparins (LMWHs), derived from unfractionated heparin (UFH) by different depolymerization procedures, vary in both their relative abilities to enhance the inhibition of FXa (anti-FXa) and thrombin (anti-FIIa), and in their physicochemical properties. Heparin 33-41 coagulation factor X Homo sapiens 202-205 17461929-1 2007 BACKGROUND: Low-molecular-weight heparins (LMWHs), derived from unfractionated heparin (UFH) by different depolymerization procedures, vary in both their relative abilities to enhance the inhibition of FXa (anti-FXa) and thrombin (anti-FIIa), and in their physicochemical properties. Heparin 33-41 coagulation factor X Homo sapiens 212-215 17461929-1 2007 BACKGROUND: Low-molecular-weight heparins (LMWHs), derived from unfractionated heparin (UFH) by different depolymerization procedures, vary in both their relative abilities to enhance the inhibition of FXa (anti-FXa) and thrombin (anti-FIIa), and in their physicochemical properties. Heparin 33-40 coagulation factor X Homo sapiens 202-205 17461929-1 2007 BACKGROUND: Low-molecular-weight heparins (LMWHs), derived from unfractionated heparin (UFH) by different depolymerization procedures, vary in both their relative abilities to enhance the inhibition of FXa (anti-FXa) and thrombin (anti-FIIa), and in their physicochemical properties. Heparin 33-40 coagulation factor X Homo sapiens 212-215 17176096-2 2006 The two analogue peptides were found to be equally effective for neutralization of the anticoagulant activity of heparin, as measured by restoration of the activity of serine protease factor Xa by the Coatest heparin method. Heparin 113-120 coagulation factor X Homo sapiens 184-193 16778722-1 2006 This study was designed to develop methods for monitoring of the selective factor Xa inhibitor fondaparinux sodium (ARIXTRA) based on standard laboratory methods for the chromogenic determination of the anti-factor Xa activity of low molecular weight heparin. Heparin 251-258 coagulation factor X Homo sapiens 75-84 17004727-0 2006 Heparin derivatives as inhibitors of BACE-1, the Alzheimer"s beta-secretase, with reduced activity against factor Xa and other proteases. Heparin 0-7 coagulation factor X Homo sapiens 107-116 16940049-6 2006 Rates of heparin-independent Y131L and Y131A factor Xa inhibition were 25 and 29 times faster than for the control and Y131F, suggesting that Tyr(131) ring interactions with neighboring helix D and strand 2A residues shift the uncatalyzed native-to-activated conformational equilibrium toward the RCL-inserted state. Heparin 9-16 coagulation factor X Homo sapiens 45-54 16778722-1 2006 This study was designed to develop methods for monitoring of the selective factor Xa inhibitor fondaparinux sodium (ARIXTRA) based on standard laboratory methods for the chromogenic determination of the anti-factor Xa activity of low molecular weight heparin. Heparin 251-258 coagulation factor X Homo sapiens 208-217 16841652-1 2006 It is possible to successfully determine both the activity against activated factor Xa in animals plasma after heparins administration and specific activity against activated factor Xa of new anticoagulants by means of the domestic diagnostic kit "Reachrom-Heparin" developed by the company "Renam". Heparin 111-119 coagulation factor X Homo sapiens 77-86 16517611-1 2006 We previously showed that conformational activation of the anticoagulant serpin, antithrombin, by heparin generates new exosites in strand 3 of beta-sheet C, which promote the reaction of the inhibitor with the target proteases, factor Xa and factor IXa. Heparin 98-105 coagulation factor X Homo sapiens 229-253 16619025-5 2006 Here we present the crystallographic structure of the recognition (Michaelis) complex between heparin-activated AT and S195A fXa, revealing the extensive exosite contacts that confer specificity. Heparin 94-101 coagulation factor X Homo sapiens 125-128 16619025-6 2006 The heparin-induced conformational change in AT is required to allow simultaneous contacts within the active site and two distinct exosites of fXa (36-loop and the autolysis loop). Heparin 4-11 coagulation factor X Homo sapiens 143-146 16618121-2 2006 It has been demonstrated that a unique pentasaccharide fragment of heparin (H5) activates AT by exposing an exosite on the serpin that is a recognition site for interaction with the basic autolysis loop (residues 143-154) of fXa. Heparin 67-74 coagulation factor X Homo sapiens 225-228 16618121-4 2006 To understand the mechanism by which heparin activation of AT improves the reactivity of the serpin with fXa, the H5-catalyzed reaction of AT with fXa, fXa R150A, and fXa S195A was studied using rapid kinetic, surface plasmon resonance, and competitive binding methods. Heparin 37-44 coagulation factor X Homo sapiens 105-108 16618121-6 2006 On the other hand, an approximately 70-saccharide, high-affinity heparin-catalyzed AT inhibition of both fXa derivatives showed a saturable dependence on the inhibitor concentration, yielding an identical rate constant of approximately 20 s(-)(1), but different ternary fXa-heparin-AT dissociation constants (K(E,ATH)) of approximately 130 and approximately 1780 nM for wild-type and R150A fXa, respectively. Heparin 65-72 coagulation factor X Homo sapiens 105-108 16618121-6 2006 On the other hand, an approximately 70-saccharide, high-affinity heparin-catalyzed AT inhibition of both fXa derivatives showed a saturable dependence on the inhibitor concentration, yielding an identical rate constant of approximately 20 s(-)(1), but different ternary fXa-heparin-AT dissociation constants (K(E,ATH)) of approximately 130 and approximately 1780 nM for wild-type and R150A fXa, respectively. Heparin 65-72 coagulation factor X Homo sapiens 270-273 16618121-6 2006 On the other hand, an approximately 70-saccharide, high-affinity heparin-catalyzed AT inhibition of both fXa derivatives showed a saturable dependence on the inhibitor concentration, yielding an identical rate constant of approximately 20 s(-)(1), but different ternary fXa-heparin-AT dissociation constants (K(E,ATH)) of approximately 130 and approximately 1780 nM for wild-type and R150A fXa, respectively. Heparin 65-72 coagulation factor X Homo sapiens 270-273 16618121-6 2006 On the other hand, an approximately 70-saccharide, high-affinity heparin-catalyzed AT inhibition of both fXa derivatives showed a saturable dependence on the inhibitor concentration, yielding an identical rate constant of approximately 20 s(-)(1), but different ternary fXa-heparin-AT dissociation constants (K(E,ATH)) of approximately 130 and approximately 1780 nM for wild-type and R150A fXa, respectively. Heparin 274-281 coagulation factor X Homo sapiens 105-108 16146728-2 2006 Various types of low molecular weight (LMW) heparin, which function as semi-selective and indirect FXa inhibitors, are replacing unfractionated heparin (UFH) as agents for the prevention and treatment of venous thromboembolism (VTE), as well as in initial treatment for coronary events. Heparin 44-51 coagulation factor X Homo sapiens 99-102 16601834-1 2006 Plasminogen activator inhibitor type 1 (PAI-1), the primary inhibitor of plasminogen activators, also forms high molecular weight complexes with either thrombin or factor Xa (FXa) in the presence of heparin, resulting in the loss of mutual activities of enzyme and inhibitor. Heparin 199-206 coagulation factor X Homo sapiens 164-173 16601834-1 2006 Plasminogen activator inhibitor type 1 (PAI-1), the primary inhibitor of plasminogen activators, also forms high molecular weight complexes with either thrombin or factor Xa (FXa) in the presence of heparin, resulting in the loss of mutual activities of enzyme and inhibitor. Heparin 199-206 coagulation factor X Homo sapiens 175-178 16601834-6 2006 In the presence of vitronectin (Vn), the inhibition of thrombin and FXa by PAI-1 was further promoted by both types of heparin but to a significantly lesser extent with LMW-heparin. Heparin 119-126 coagulation factor X Homo sapiens 68-71 16398531-7 2006 Heparin was covalently bound at a high level (1.11 +/- 0.06 mug/cm(2)) and was shown to be active, with demonstrable Factor Xa inhibition and platelet factor IV binding. Heparin 0-7 coagulation factor X Homo sapiens 117-126 15795534-10 2005 The anti-FXa assay appears to be a better method for monitoring heparin subjects than the aPTT due to the lack of effect of pre-analytical variables. Heparin 64-71 coagulation factor X Homo sapiens 9-12 15895163-9 2005 Recently it was demonstrated that ixolaris binds to heparin-binding exosite of FXa, thus impairing the recognition of prothrombin by the enzyme. Heparin 52-59 coagulation factor X Homo sapiens 79-82 16360197-7 2006 RESULTS AND CONCLUSIONS: The results show clear age-related differences in APTT for the same Anti-Factor Xa heparin concentration. Heparin 108-115 coagulation factor X Homo sapiens 98-107 16360197-9 2006 The Anti-Factor IIa activity of heparin for a given Anti-Factor Xa activity also differed between age-specific plasma pools. Heparin 32-39 coagulation factor X Homo sapiens 57-66 17323590-1 2006 The antithrombin binding sequence of heparin, a pentasaccharide, has been synthesized as fondaparinux, an indirect, selective, and reversible factor Xa inhibitor. Heparin 37-44 coagulation factor X Homo sapiens 142-151 15941584-7 2005 The surface-bound heparin is shown to possess anti-coagulant activity in the range of 4.80-6.39 mIU/cm2 as determined by a chromogenic anti-Factor Xa assay. Heparin 18-25 coagulation factor X Homo sapiens 140-149 15941584-9 2005 The proposed polymeric coatings are capable of functioning by two complementary anti-thrombotic mechanisms, one based on the potent anti-platelet activity of NO, and the other the result of the ability of immobilized heparin to inhibit Factor Xa and thrombin (Factor IIa). Heparin 217-224 coagulation factor X Homo sapiens 236-245 16113752-5 2005 Based on standard laboratory methods for the chromogenic determination of the anti-factor Xa activity of low molecular weight heparin several chromogenic substrate assays were published for monitoring. Heparin 126-133 coagulation factor X Homo sapiens 83-92 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 74-81 coagulation factor X Homo sapiens 65-68 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 74-81 coagulation factor X Homo sapiens 150-153 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 74-81 coagulation factor X Homo sapiens 150-153 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 74-81 coagulation factor X Homo sapiens 150-153 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 174-181 coagulation factor X Homo sapiens 65-68 15617517-3 2005 Here we provide evidence that Ixolaris binds specifically to the FXa HBE (heparin-binding exosite), since (i) it markedly decreases the inhibition of FXa by the antithrombin-heparin but not the antithrombin-pentasaccharide complex, (ii) it impairs FXa binding to Sepharose-immobilized heparin, and (iii) it allosterically modulates the catalytic activity of FXa for small chromogenic substrates (S-2765). Heparin 174-181 coagulation factor X Homo sapiens 65-68 15199558-3 2004 In the early 1980s it was discovered that a unique pentasaccharide domain in some heparin chains activates antithrombin III (AT-III), a serine protease inhibitor that blocks thrombin and factor Xa in the coagulation cascade. Heparin 82-89 coagulation factor X Homo sapiens 187-196 15633734-4 2004 The newest, third generation heparin, the pentasaccharide inhibits specifically FXa. Heparin 29-36 coagulation factor X Homo sapiens 80-83 15219196-2 2004 The serpin antithrombin (AT) is an important physiological regulator of FXa activity in an inhibition reaction that is enhanced by heparin. Heparin 131-138 coagulation factor X Homo sapiens 72-75 15219196-3 2004 Recently, Rezaie showed that calcium further enhanced the heparin-catalyzed AT inhibition of FXa by promoting "ternary complex" formation, and these results showed a role for the gamma-carboxyl-glutamate (Gla)-domain of FXa. Heparin 58-65 coagulation factor X Homo sapiens 93-96 15219196-3 2004 Recently, Rezaie showed that calcium further enhanced the heparin-catalyzed AT inhibition of FXa by promoting "ternary complex" formation, and these results showed a role for the gamma-carboxyl-glutamate (Gla)-domain of FXa. Heparin 58-65 coagulation factor X Homo sapiens 220-223 15219196-7 2004 Interestingly, three different effects were found with the recombinant FXa Gla-mutants for AT-heparin inhibition: (i) Gla-->Asp 14 and 29 were enhanced without calcium; (ii) Gla-->Asp 16 and 26 were not enhanced by calcium; and (iii) Gla-->Asp 19 was essentially the same as wild-type recombinant FXa. Heparin 94-101 coagulation factor X Homo sapiens 71-74 15219196-7 2004 Interestingly, three different effects were found with the recombinant FXa Gla-mutants for AT-heparin inhibition: (i) Gla-->Asp 14 and 29 were enhanced without calcium; (ii) Gla-->Asp 16 and 26 were not enhanced by calcium; and (iii) Gla-->Asp 19 was essentially the same as wild-type recombinant FXa. Heparin 94-101 coagulation factor X Homo sapiens 306-309 15543318-3 2004 The results show that the anticoagulant effects of the latter three heparins under conditions approximating physiologic are exerted almost exclusively by acceleration of the inactivation of thrombin, factor Xa and factor IXa to near diffusion-controlled rate constants of approximately 10(6) - 10(7) M(-1).s(-1). Heparin 68-76 coagulation factor X Homo sapiens 200-224 14532267-1 2003 We have previously shown that exosites in antithrombin outside the P6-P3" reactive loop region become available upon heparin activation to promote rapid inhibition of the target proteases, factor Xa and factor IXa. Heparin 117-124 coagulation factor X Homo sapiens 189-213 15321411-2 2004 The effects of differences in coagulation status on the action of heparin cannot be measured by specific laboratory tests such as aPTT or anti-Factor Xa assay. Heparin 66-73 coagulation factor X Homo sapiens 143-152 23105443-16 2004 The clinical tolerability and the efficacy of low molecular weight heparins has established that inhibition of further thrombin generation, by blocking factor Xa alone can be an effective way of preventing thrombus growth without inactivating thrombin. Heparin 67-75 coagulation factor X Homo sapiens 152-161 15570557-0 2004 Evaluation of a chromogenic assay to measure the factor Xa inhibitory activity of unfractionated heparin in canine plasma. Heparin 97-104 coagulation factor X Homo sapiens 49-58 15570557-2 2004 Factor Xa inhibitory assays (to measure anti-Xa activity) are used to adjust UFH dosage and define safe and effective regimens for specific thrombotic disorders in humans. Heparin 77-80 coagulation factor X Homo sapiens 0-9 14670838-12 2004 Heparin may inhibit the mitogenic effects of thrombin and FXa in human SMCs by preventing bFGF binding to FGFR-1. Heparin 0-7 coagulation factor X Homo sapiens 58-61 14596625-1 2003 Recent studies have demonstrated the existence of a Ca(2+)-dependent heparin-binding site on factor Xa. Heparin 69-76 coagulation factor X Homo sapiens 93-102 14596625-2 2003 To characterize this heparin-binding site, the extrinsic fluorescence of fluorescein-labeled, active site-blocked factor Xa was monitored as it was titrated with glycosaminoglycans of various sulfate content and chain length. Heparin 21-28 coagulation factor X Homo sapiens 114-123 14575696-8 2003 It is proposed that PF4 inhibited the sequence of events recapitulated in the template mechanism describing heparin-dependent inhibition of fXa. Heparin 108-115 coagulation factor X Homo sapiens 140-143 14511765-1 2003 In the blood coagulation cascade, human antithrombin III (hAT III) acts as an inhibitor of serine proteases such as thrombin and factor Xa, and this anticoagulatory glycoprotein requires the binding of heparin for its activation. Heparin 202-209 coagulation factor X Homo sapiens 129-138 14575696-4 2003 To shed light on the mechanism of PF4, studies of HS/heparin-catalyzed fXa inactivation by AT were undertaken. Heparin 53-60 coagulation factor X Homo sapiens 71-74 12941037-9 2003 Moreover, both heparin and SanOrg123781A significantly inhibited fibrinopeptide A generated by the action of clot-bound thrombin on fibrinogen but also by free thrombin generated from prothrombin by clot-bound FXa with IC50 values of 4 +/- 0.6 and 1 +/- 0.1 micro g mL-1, respectively. Heparin 15-22 coagulation factor X Homo sapiens 210-213 12832413-7 2003 Heparin binding to f.Xa was previously shown to be promoted in the presence of Ca2+. Heparin 0-7 coagulation factor X Homo sapiens 19-23 12832413-9 2003 Thus, Ca2+ promotes heparin-catalyzed inhibition of f.IXa and f.Xa by antithrombin by augmenting the template mechanism. Heparin 20-27 coagulation factor X Homo sapiens 62-66 12941037-4 2003 In buffer, heparin and SanOrg123781A inhibited FXa and thrombin at similar concentrations [concentration inhibiting 50% (IC50) of Xa and IIa activity were, respectively: heparin 120 +/- 7 and 3 +/- 1 ng mL-1; SanOrg123781A 77 +/- 5 and 4 +/- 1 ng mL-1]. Heparin 11-18 coagulation factor X Homo sapiens 47-50 12941037-4 2003 In buffer, heparin and SanOrg123781A inhibited FXa and thrombin at similar concentrations [concentration inhibiting 50% (IC50) of Xa and IIa activity were, respectively: heparin 120 +/- 7 and 3 +/- 1 ng mL-1; SanOrg123781A 77 +/- 5 and 4 +/- 1 ng mL-1]. Heparin 170-177 coagulation factor X Homo sapiens 47-50 13679071-2 2003 AT inhibits clotting factors such as thrombin and factor Xa, a reaction catalyzed by heparin. Heparin 85-92 coagulation factor X Homo sapiens 50-59 12871328-1 2003 Antithrombin and its cofactor, heparin, target both the product of prothrombin activation by prothrombinase, thrombin, as well as the enzyme responsible for the reaction, factor (F)Xa. Heparin 31-38 coagulation factor X Homo sapiens 93-107 12695507-1 2003 Covalent antithrombin-heparin (ATH) complexes, formed spontaneously between antithrombin (AT) and unfractionated standard heparin (H), have a potent ability to catalyze the inhibition of factor Xa (or thrombin) by added AT. Heparin 22-29 coagulation factor X Homo sapiens 187-196 12695507-10 2003 Thus, exogenous AT can compete with the AT moiety of ATH for binding to the covalently linked heparin chain, leading to catalytic inhibition of factor Xa or thrombin. Heparin 94-101 coagulation factor X Homo sapiens 144-153 12941037-7 2003 We showed that heparin and SanOrg123781A were able to inhibit fragment F1+2 generation induced by clot-bound FXa with IC50 values of 2 +/- 0.5 micro g mL-1 and 0.6 +/- 0.2 micro g mL-1, respectively. Heparin 15-22 coagulation factor X Homo sapiens 109-112 12871328-9 2003 Therefore, in the presence of unfractionated heparin, fondaparinux, or enoxaparin, prothrombinase is profoundly protected from antithrombin. Heparin 45-52 coagulation factor X Homo sapiens 83-97 12606556-11 2003 Furthermore, cleavage at Lys(36) appears to be selectively modulated by the C-terminal acidic region of A1, a region that may interact with factor Xa via its heparin-binding exosite. Heparin 158-165 coagulation factor X Homo sapiens 140-149 12948833-1 2003 In the blood coagulation cascade, heparin activates human plasma antithrombin III (hAT III), resulting in the inhibition of factor Xa. Heparin 34-41 coagulation factor X Homo sapiens 124-133 12948833-3 2003 Therefore, attention has focused on the development of low molecular weight heparins (LMW-heparins) that inhibit factor Xa but not thrombin. Heparin 76-84 coagulation factor X Homo sapiens 113-122 12948833-3 2003 Therefore, attention has focused on the development of low molecular weight heparins (LMW-heparins) that inhibit factor Xa but not thrombin. Heparin 90-98 coagulation factor X Homo sapiens 113-122 12948833-5 2003 Of all the tested HBPs, hAT III (123-139) exhibited the highest affinity with heparin and showed an inhibitory effect on the heparin-induced enhancement of hAT III activity toward factor Xa, indicating that hAT III (123-139) specifically interacts with the active region in heparin. Heparin 125-132 coagulation factor X Homo sapiens 180-189 12948833-5 2003 Of all the tested HBPs, hAT III (123-139) exhibited the highest affinity with heparin and showed an inhibitory effect on the heparin-induced enhancement of hAT III activity toward factor Xa, indicating that hAT III (123-139) specifically interacts with the active region in heparin. Heparin 125-132 coagulation factor X Homo sapiens 180-189 12701115-4 2003 Moreover, eosinophil peroxidase by itself functioned as a powerful procoagulant and also inhibited the anticoagulant actions of heparin in a chromogenic assay for antithrombin III/factor Xa activity. Heparin 128-135 coagulation factor X Homo sapiens 180-189 12172443-2 2002 Selective factor Xa inhibition is a new antithrombotic approach designed to avoid difficulties associated with heparins and other current anticoagulants. Heparin 111-119 coagulation factor X Homo sapiens 10-19 12947723-0 2003 [Factor Xa inhibitory assay to detect plasma heparin concentrations during and after cardiopulmonary bypass]. Heparin 45-52 coagulation factor X Homo sapiens 1-10 12536119-2 2002 Heparin activates antithrombin both by inducing conformational changes in the protein that specifically enhances factor Xa binding and by providing a surface to promote thrombin or factor Xa binding alongside antithrombin in a ternary bridging complex. Heparin 0-7 coagulation factor X Homo sapiens 113-122 12536119-2 2002 Heparin activates antithrombin both by inducing conformational changes in the protein that specifically enhances factor Xa binding and by providing a surface to promote thrombin or factor Xa binding alongside antithrombin in a ternary bridging complex. Heparin 0-7 coagulation factor X Homo sapiens 181-190 12740133-5 2003 Heparin doses were adjusted to achieve subtherapeutic peak anti-factor Xa heparin activity levels of 0.11-0.25 units/mL. Heparin 0-7 coagulation factor X Homo sapiens 64-73 12540961-2 2003 Here, the anti-fXa and anti-prothrombinase activities of DX-9065a which is an active-site directed inhibitor of fXa, and therapeutic heparins which are dependent on antithrombin (AT) for their anticoagulant function, were studied in amidolytic and proteolytic activity assays. Heparin 133-141 coagulation factor X Homo sapiens 28-42 12478357-7 2002 Heparin anticoagulation may be ineffective because the rate of coagulation that occurs on the surfaces of dysfunctional endothelial surfaces exceeds the capacity of heparin/antithrombin-III inhibitor complexes to bind and block the factor Xa and thrombin that are generated on these surfaces. Heparin 0-7 coagulation factor X Homo sapiens 232-241 12168126-1 2002 OBJECTIVE: Neonates who are treated with low-molecular-weight heparin require repeated venipunctures to monitor anti-factor Xa (anti-FXa) levels. Heparin 62-69 coagulation factor X Homo sapiens 133-136 12353073-3 2002 The variant forms SDS-stable complexes with activated factor X (fXa) and its thermal stability and rate of factor Xa inhibition in the absence of heparin are identical to those of normal antithrombin. Heparin 146-153 coagulation factor X Homo sapiens 64-67 12168126-7 2002 When 0.5, 3.0, or 4.0 ml of blood was cleared from the UAC before withdrawing the test sample, heparin contaminated the test (anti-FXa levels > or = 0.1 U/ml) in 66%, 16%, and 8% of samples, respectively. Heparin 95-102 coagulation factor X Homo sapiens 131-134 12211411-3 2002 Understanding the heparin structure led to the development of LMWHs, synthetic heparinomimetics, antithrombin and anti-Factor Xa agents. Heparin 18-25 coagulation factor X Homo sapiens 119-128 11854268-3 2002 A specific pentasaccharide sequence (H5) in high affinity heparin induces a conformational change in antithrombin that is particularly important for factor Xa (fXa) inhibition. Heparin 58-65 coagulation factor X Homo sapiens 149-158 12244482-0 2002 Effects of calcium ions on the interactions between antithrombin and factor Xa mediated by variously sulfated, semisynthetic low-molecular-weight heparins. Heparin 146-154 coagulation factor X Homo sapiens 69-78 12244482-1 2002 A homogeneous set of low-molecular weight heparins, chemically modified to yield different degrees of sulfation, were investigated for their ability to interfere with the antithrombin (AT)-factor Xa (FXa) interaction process in the presence or absence of physiological concentrations of calcium ions. Heparin 42-50 coagulation factor X Homo sapiens 189-198 12244482-1 2002 A homogeneous set of low-molecular weight heparins, chemically modified to yield different degrees of sulfation, were investigated for their ability to interfere with the antithrombin (AT)-factor Xa (FXa) interaction process in the presence or absence of physiological concentrations of calcium ions. Heparin 42-50 coagulation factor X Homo sapiens 200-203 12244482-3 2002 Our data suggest that AT binding to heparin represents the main factor driving the FXa inhibition process. Heparin 36-43 coagulation factor X Homo sapiens 83-86 11854268-3 2002 A specific pentasaccharide sequence (H5) in high affinity heparin induces a conformational change in antithrombin that is particularly important for factor Xa (fXa) inhibition. Heparin 58-65 coagulation factor X Homo sapiens 160-163 11881992-1 2002 Conformational activation of antithrombin is a critical mechanism for the inhibition of factor Xa, a proteinase of the blood coagulation cascade, and is typically achieved with heparin, a polyanionic polysaccharide clinically used for anticoagulation. Heparin 177-184 coagulation factor X Homo sapiens 88-97 11741963-1 2002 Antithrombin requires allosteric activation by heparin for efficient inhibition of its target protease, factor Xa. Heparin 47-54 coagulation factor X Homo sapiens 104-113 11741963-2 2002 A pentasaccharide sequence found in heparin activates antithrombin by inducing conformational changes that affect the reactive center of the inhibitor resulting in optimal recognition by factor Xa. Heparin 36-43 coagulation factor X Homo sapiens 187-196 11677228-7 2001 The free energy change, Delta G, for the antithrombin/heparin interaction was calculated from the dissociation constant, determined by functional titrations of heparin with antithrombin at fixed concentrations of the coagulation protease factor Xa. Heparin 54-61 coagulation factor X Homo sapiens 238-247 11886166-4 2002 We show that vIL-10 will bind to heparin and use this property to purify vIL-10 from factor Xa cleaved products and trace contaminants using heparin agarose chromatography. Heparin 33-40 coagulation factor X Homo sapiens 85-94 11886166-4 2002 We show that vIL-10 will bind to heparin and use this property to purify vIL-10 from factor Xa cleaved products and trace contaminants using heparin agarose chromatography. Heparin 141-148 coagulation factor X Homo sapiens 85-94 14727968-18 2002 The clinical tolerability and the efficacy of low molecular weight heparins led to the concept that inhibition of further thrombin generation, by blocking factor Xa alone, can be an effective way of preventing thrombus growth without inactivating thrombin. Heparin 67-75 coagulation factor X Homo sapiens 155-164 11668417-0 2001 Effects of sulfation on antithrombin-thrombin/factor Xa interactions in semisynthetic low molecular weight heparins. Heparin 107-115 coagulation factor X Homo sapiens 46-55 11668418-0 2001 Cellular effects of factor Xa on vascular smooth muscle cells--inhibition by heparins? Heparin 77-85 coagulation factor X Homo sapiens 20-29 11668418-3 2001 Unfractionated heparin (UFH) as well as low molecular weight heparin (LMWH) (enoxaparin) inhibited the mitogenic effects of FXa, thrombin and fetal calf serum (FCS), but did not reduce mitogenesis induced by PDGF. Heparin 15-22 coagulation factor X Homo sapiens 124-127 11687304-6 2001 A similar 10(4)-10(5)-fold enhancement in the reactivity of factor Xa with prethrombin-2 and the HAT mutants was observed in the presence of the cofactors Va and heparin, respectively. Heparin 162-169 coagulation factor X Homo sapiens 60-69 11668418-3 2001 Unfractionated heparin (UFH) as well as low molecular weight heparin (LMWH) (enoxaparin) inhibited the mitogenic effects of FXa, thrombin and fetal calf serum (FCS), but did not reduce mitogenesis induced by PDGF. Heparin 24-27 coagulation factor X Homo sapiens 124-127 11434701-1 2001 Heparin-induced thrombocytopenia (HIT) is a hypercoagulable syndrome strongly associated with thrombosis that is usually treated with drugs that inhibit factor Xa (danaparoid) or thrombin (lepirudin). Heparin 0-7 coagulation factor X Homo sapiens 153-162 11668418-3 2001 Unfractionated heparin (UFH) as well as low molecular weight heparin (LMWH) (enoxaparin) inhibited the mitogenic effects of FXa, thrombin and fetal calf serum (FCS), but did not reduce mitogenesis induced by PDGF. Heparin 61-68 coagulation factor X Homo sapiens 124-127 11668418-4 2001 Similarly, both UFH and LMWH inhibited the activation of extracellular signal-regulated kinase (ERK-1/2) by FXa, thrombin and FCS, but not by PDGF. Heparin 16-19 coagulation factor X Homo sapiens 108-111 11531671-0 2001 Maternal anti-factor Xa activity following subcutaneous unfractionated heparin after Caesarean section. Heparin 71-78 coagulation factor X Homo sapiens 14-23 11380263-1 2001 Activation of antithrombin by high-affinity heparin as an inhibitor of factor Xa has been ascribed to an allosteric switch between two conformations of the reactive center loop. Heparin 44-51 coagulation factor X Homo sapiens 71-80 11278943-10 2001 In the absence of prothrombin, FVa decreased the second order rate constant for inhibition by the AT-heparin complex from 1.58 x 10(7) m(-1) s(-1), for FXa, Ca(2+), and PCPS, to 7.72 x 10(6) m(-1) s(-1). Heparin 101-108 coagulation factor X Homo sapiens 152-155 11287128-1 2001 Fluorescence and stopped flow methods were used to compare clinically used heparins with regard to their ability to bind to antithrombin and to accelerate the inactivation of factor Xa. Heparin 75-83 coagulation factor X Homo sapiens 175-184 11290592-3 2001 There are conflicting results as to whether anticoagulant heparins can catalyze the antithrombin inhibition of factor Xa in the prothrombinase complex (factor Va, negatively charged membrane surfaces, and calcium ion), which is the physiologically relevant form of the proteinase responsible for the activation of prothrombin to thrombin during the blood coagulation process. Heparin 58-66 coagulation factor X Homo sapiens 111-120 11290592-3 2001 There are conflicting results as to whether anticoagulant heparins can catalyze the antithrombin inhibition of factor Xa in the prothrombinase complex (factor Va, negatively charged membrane surfaces, and calcium ion), which is the physiologically relevant form of the proteinase responsible for the activation of prothrombin to thrombin during the blood coagulation process. Heparin 58-66 coagulation factor X Homo sapiens 128-142 11290592-4 2001 In this study, a novel assay system was developed to compare the catalytic effect of different molecular-weight heparins in the antithrombin inhibition of factor Xa, either in free form or assembled into the prothrombinase complex during the process of prothrombin activation. Heparin 112-120 coagulation factor X Homo sapiens 155-164 11290592-4 2001 In this study, a novel assay system was developed to compare the catalytic effect of different molecular-weight heparins in the antithrombin inhibition of factor Xa, either in free form or assembled into the prothrombinase complex during the process of prothrombin activation. Heparin 112-120 coagulation factor X Homo sapiens 208-222 11290592-5 2001 This assay takes advantage of the unique property of a recombinant mutant antithrombin, which, similar to the wild-type antithrombin, rapidly inhibits factor Xa, but not thrombin, in the presence of heparin. Heparin 199-206 coagulation factor X Homo sapiens 151-160 11278930-0 2001 Heparin enhances the specificity of antithrombin for thrombin and factor Xa independent of the reactive center loop sequence. Heparin 0-7 coagulation factor X Homo sapiens 66-75 11278930-2 2001 Heparin activates the primary serpin inhibitor of blood clotting proteinases, antithrombin, both by an allosteric conformational change mechanism that specifically enhances factor Xa inactivation and by a ternary complex bridging mechanism that promotes the inactivation of thrombin and other target proteinases. Heparin 0-7 coagulation factor X Homo sapiens 173-182 11287128-4 2001 The rate of factor Xa inhibition by antithrombin increased with the concentration of the examined heparins to the same limiting value, but the concentration required for maximal acceleration depended on the preparation. Heparin 98-106 coagulation factor X Homo sapiens 12-21 11287128-6 2001 In contrast, in the presence of Ca UFH accelerated the inhibition of factor Xa by antithrombin 10-fold more efficiently than comparable concentrations of the high affinity fractions of enoxaparin and fragmin. Heparin 35-38 coagulation factor X Homo sapiens 69-78 11287128-8 2001 In conclusion, under physiologic conditions the anti-factor Xa activity of heparin results from a composite effect of chain length and the content of material with high affinity to antithrombin. Heparin 75-82 coagulation factor X Homo sapiens 53-62 11100007-2 2000 Current and evolving technologies to monitor the extent of inhibition of platelet aggregation and activity of factor Xa caused by IIb/IIIa antagonists and low-molecular-weight heparin, respectively, will be covered in this overview. Heparin 176-183 coagulation factor X Homo sapiens 110-119 11134031-0 2001 Hypersulfated low molecular weight heparin with reduced affinity for antithrombin acts as an anticoagulant by inhibiting intrinsic tenase and prothrombinase. Heparin 35-42 coagulation factor X Homo sapiens 142-156 11009624-0 2000 Calcium enhances heparin catalysis of the antithrombin-factor Xa reaction by promoting the assembly of an intermediate heparin-antithrombin-factor Xa bridging complex. Heparin 17-24 coagulation factor X Homo sapiens 55-64 11369259-2 2000 Binding of a full-length heparin chain to this site of factor Xa in the presence of calcium makes a significant contribution to acceleration of the proteinase inhibition by antithrombin through a ternary complex bridging or template mechanism. Heparin 25-32 coagulation factor X Homo sapiens 55-64 11009624-0 2000 Calcium enhances heparin catalysis of the antithrombin-factor Xa reaction by promoting the assembly of an intermediate heparin-antithrombin-factor Xa bridging complex. Heparin 17-24 coagulation factor X Homo sapiens 140-149 11125607-2 2000 Like standard heparin, these anticoagulants inhibit activation of a number of coagulation enzymes, but low molecular weight heparins have their primary inhibitory effect on factor Xa. Heparin 124-132 coagulation factor X Homo sapiens 173-182 11009624-2 2000 Heparin catalyzes the inhibition of factor Xa by antithrombin mainly through an allosteric activation of the serpin inhibitor, but an alternative heparin bridging mechanism has been suggested to enhance the catalysis in the presence of physiologic calcium levels due to calcium interactions with the Gla domain exposing a heparin binding exosite in factor Xa. Heparin 0-7 coagulation factor X Homo sapiens 36-45 11009624-2 2000 Heparin catalyzes the inhibition of factor Xa by antithrombin mainly through an allosteric activation of the serpin inhibitor, but an alternative heparin bridging mechanism has been suggested to enhance the catalysis in the presence of physiologic calcium levels due to calcium interactions with the Gla domain exposing a heparin binding exosite in factor Xa. Heparin 0-7 coagulation factor X Homo sapiens 349-358 11009624-2 2000 Heparin catalyzes the inhibition of factor Xa by antithrombin mainly through an allosteric activation of the serpin inhibitor, but an alternative heparin bridging mechanism has been suggested to enhance the catalysis in the presence of physiologic calcium levels due to calcium interactions with the Gla domain exposing a heparin binding exosite in factor Xa. Heparin 146-153 coagulation factor X Homo sapiens 36-45 11009624-3 2000 To provide direct evidence for this bridging mechanism, we studied the heparin-catalyzed reaction of antithrombin with factor Xa, Gla-domainless factor Xa (GDFXa), and a heparin binding exosite mutant of GDFXa in the absence and presence of calcium using rapid kinetic methods. Heparin 71-78 coagulation factor X Homo sapiens 119-128 11009624-3 2000 To provide direct evidence for this bridging mechanism, we studied the heparin-catalyzed reaction of antithrombin with factor Xa, Gla-domainless factor Xa (GDFXa), and a heparin binding exosite mutant of GDFXa in the absence and presence of calcium using rapid kinetic methods. Heparin 71-78 coagulation factor X Homo sapiens 145-154 11009624-4 2000 The pseudo-first-order rate constant for factor Xa inhibition by antithrombin complexed with a long-chain approximately 70-saccharide heparin showed a saturable dependence on inhibitor concentration in the presence but not in the absence of 2.5 mM Ca(2+), indicating the formation of an intermediate heparin-serpin-proteinase encounter complex with a dissociation constant of approximately 90 nM prior to formation of the stable serpin-proteinase complex with a rate constant of approximately 20 s(-1). Heparin 134-141 coagulation factor X Homo sapiens 41-50 11009624-7 2000 These findings suggest that binding of full-length heparin chains to an exosite of factor Xa in the presence of Ca(2+) produces a chain-length-dependent lowering of the dissociation constant for assembly of the intermediate heparin-antithrombin-factor Xa encounter complex, resulting in a several 100-fold rate enhancement by a heparin bridging mechanism. Heparin 51-58 coagulation factor X Homo sapiens 83-92 11009624-7 2000 These findings suggest that binding of full-length heparin chains to an exosite of factor Xa in the presence of Ca(2+) produces a chain-length-dependent lowering of the dissociation constant for assembly of the intermediate heparin-antithrombin-factor Xa encounter complex, resulting in a several 100-fold rate enhancement by a heparin bridging mechanism. Heparin 51-58 coagulation factor X Homo sapiens 245-254 11009624-7 2000 These findings suggest that binding of full-length heparin chains to an exosite of factor Xa in the presence of Ca(2+) produces a chain-length-dependent lowering of the dissociation constant for assembly of the intermediate heparin-antithrombin-factor Xa encounter complex, resulting in a several 100-fold rate enhancement by a heparin bridging mechanism. Heparin 224-231 coagulation factor X Homo sapiens 83-92 11009624-7 2000 These findings suggest that binding of full-length heparin chains to an exosite of factor Xa in the presence of Ca(2+) produces a chain-length-dependent lowering of the dissociation constant for assembly of the intermediate heparin-antithrombin-factor Xa encounter complex, resulting in a several 100-fold rate enhancement by a heparin bridging mechanism. Heparin 224-231 coagulation factor X Homo sapiens 245-254 10913257-9 2000 The rate constants for inhibition of thrombin and factor Xa by the complexes between antithrombin and full-length heparin or pentasaccharide were unaffected by both mutations, indicating that neither Lys136 nor Lys139 is involved in heparin activation of the inhibitor. Heparin 114-121 coagulation factor X Homo sapiens 50-59 10660568-2 2000 It has been proposed that residues P15 and P14 are expelled from beta-sheet A of antithrombin by heparin binding, permitting better interaction of the reactive center loop with factor Xa. Heparin 97-104 coagulation factor X Homo sapiens 177-186 10728020-0 2000 Enoxaparin, a low molecular weight heparin, inhibits platelet-dependent prothrombinase assembly and activity by factor-Xa neutralization. Heparin 35-42 coagulation factor X Homo sapiens 72-86 10728020-0 2000 Enoxaparin, a low molecular weight heparin, inhibits platelet-dependent prothrombinase assembly and activity by factor-Xa neutralization. Heparin 35-42 coagulation factor X Homo sapiens 112-121 10722716-1 2000 Antithrombin requires heparin for efficient inhibition of the final two proteinases of the blood coagulation cascade, factor Xa and thrombin. Heparin 22-29 coagulation factor X Homo sapiens 118-127 11060763-3 2000 Fractionated, or low-molecular weight, heparins (LMWHs) are more selective for coagulation Factor Xa (FXa) over thrombin (FIIa). Heparin 39-47 coagulation factor X Homo sapiens 102-105 10328304-0 1999 New synthetic heparin mimetics able to inhibit thrombin and factor Xa. Heparin 14-21 coagulation factor X Homo sapiens 60-69 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 91-98 coagulation factor X Homo sapiens 127-136 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 91-98 coagulation factor X Homo sapiens 138-141 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 91-98 coagulation factor X Homo sapiens 198-201 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 218-225 coagulation factor X Homo sapiens 127-136 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 218-225 coagulation factor X Homo sapiens 138-141 10652320-1 2000 We recently demonstrated that a template mechanism makes a significant contribution to the heparin-accelerated inactivation of factor Xa (FXa) by antithrombin at physiologic Ca(2+), suggesting that FXa has a potential heparin-binding site. Heparin 218-225 coagulation factor X Homo sapiens 198-201 10652320-2 2000 Structural data indicate that 7 of the 11 basic residues of the heparin-binding exosite of thrombin are conserved at similar three-dimensional locations in FXa. Heparin 64-71 coagulation factor X Homo sapiens 156-159 10433728-1 1999 Heparin greatly accelerates the reaction between antithrombin and its target proteinases, thrombin and factor Xa, by virtue of a specific pentasaccharide sequence of heparin binding to antithrombin. Heparin 0-7 coagulation factor X Homo sapiens 103-112 10433728-1 1999 Heparin greatly accelerates the reaction between antithrombin and its target proteinases, thrombin and factor Xa, by virtue of a specific pentasaccharide sequence of heparin binding to antithrombin. Heparin 166-173 coagulation factor X Homo sapiens 103-112 15992116-1 1999 The antithrombotic efficacy of low molecular weight heparins suggest that specific inhibition of blood coagulation factor Xa (fXa) is an appropriate target for drug discovery. Heparin 52-60 coagulation factor X Homo sapiens 115-124 15992116-1 1999 The antithrombotic efficacy of low molecular weight heparins suggest that specific inhibition of blood coagulation factor Xa (fXa) is an appropriate target for drug discovery. Heparin 52-60 coagulation factor X Homo sapiens 126-129 10607857-10 1999 HepArrest binds low molecular weight heparins and causes reversal of anticoagulation by low molecular weight heparins, as determined by activated partial thromboplastin time, thrombin time, or factor Xa neutralization assays. Heparin 109-117 coagulation factor X Homo sapiens 193-202 10497166-1 1999 A sequence-specific heparin pentasaccharide activates the serpin, antithrombin, to inhibit factor Xa through an allosteric mechanism, whereas full-length heparin chains containing this sequence further activate the serpin to inhibit thrombin by an alternative bridging mechanism. Heparin 20-27 coagulation factor X Homo sapiens 91-100 19078327-3 1998 We recommend the use of a factor Xa inhibition test to regulate heparin in this patient population. Heparin 64-71 coagulation factor X Homo sapiens 26-35 10320244-3 1999 We compared these methods with respect to their ability to reflect the actual heparin concentration in plasma determined by an anti-FXa method. Heparin 78-85 coagulation factor X Homo sapiens 132-135 10926265-14 1999 The anticoagulant effect of heparin is usually monitored by the APTT, a test that is sensitive to the inhibitory effects of heparin on thrombin, factor Xa. Heparin 28-35 coagulation factor X Homo sapiens 145-154 10926265-14 1999 The anticoagulant effect of heparin is usually monitored by the APTT, a test that is sensitive to the inhibitory effects of heparin on thrombin, factor Xa. Heparin 124-131 coagulation factor X Homo sapiens 145-154 19078327-4 1998 This test measures the ability of heparin, as a cofactor of antithrombin III, to inMbit the catalytic function of factor Xa in plasma. Heparin 34-41 coagulation factor X Homo sapiens 114-123 9553135-9 1998 As the zeta2 fragment lacks the fibrinogen recognition site, the P1-P3 residues or the intact cleavage site, specific recognition of the macromolecular substrate by the exosite in prothrombinase is achieved through substrate regions, distinct from the fibrinogen recognition or heparin-binding sites, and spatially removed from structures surrounding the scissile bond. Heparin 278-285 coagulation factor X Homo sapiens 180-194 9642241-7 1998 However, in the presence of an optimum concentration of heparin ( approximately 50 nM) the inactivation rate constant of FXa in the presence of Ca2+ (k2 = 4.4 x 10(7) M-1 s-1) was 13-fold higher than the rate constant in the absence of Ca2+ (k2 = 3.5 x 10(6) M-1 s-1). Heparin 56-63 coagulation factor X Homo sapiens 121-124 9642241-9 1998 The additional cofactor effect of heparin with all FXa derivatives was a bell-shaped curve, which disappeared if the ionic strength of the reaction was increased to approximately 0.4. Heparin 34-41 coagulation factor X Homo sapiens 51-54 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 56-63 coagulation factor X Homo sapiens 83-86 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 56-63 coagulation factor X Homo sapiens 265-268 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 113-120 coagulation factor X Homo sapiens 83-86 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 113-120 coagulation factor X Homo sapiens 265-268 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 113-120 coagulation factor X Homo sapiens 83-86 9642241-10 1998 These results suggest that although the major effect of heparin in acceleration of FXa inactivation is through a heparin-induced conformational change in the reactive site loop of AT, the template effect of heparin, nevertheless, contributes significantly to rapid FXa inactivation at physiological Ca2+. Heparin 113-120 coagulation factor X Homo sapiens 265-268 9616153-9 1998 Additional studies indicated that, in the presence of phospholipid vesicles, heparin and dextran sulfate dramatically accelerate PC activation by fXa by also reducing the Km. Heparin 77-84 coagulation factor X Homo sapiens 146-149 9642241-2 1998 It is believed that heparin accelerates factor Xa (FXa) inactivation by antithrombin (AT) by conformationally activating the inhibitor rather than by bridging AT and FXa in a ternary complex (template effect). Heparin 20-27 coagulation factor X Homo sapiens 51-54 9642241-4 1998 To test the possibility that the anionic Gla domain of FXa, when not neutralized by Ca2+ ions, prevents heparin binding to FXa, the heparin and pentasaccharide dependence of FXa inactivation by AT in both the absence (100 microM EDTA) and presence of Ca2+ (2.5 mM) was studied using wild-type FXa and a FXa derivative that lacks the Gla domain (GDFXa). Heparin 104-111 coagulation factor X Homo sapiens 55-58 9642241-4 1998 To test the possibility that the anionic Gla domain of FXa, when not neutralized by Ca2+ ions, prevents heparin binding to FXa, the heparin and pentasaccharide dependence of FXa inactivation by AT in both the absence (100 microM EDTA) and presence of Ca2+ (2.5 mM) was studied using wild-type FXa and a FXa derivative that lacks the Gla domain (GDFXa). Heparin 132-139 coagulation factor X Homo sapiens 55-58 9700855-11 1998 Heparin inhibition of platelet PT activity was additive to that of c7E3 Fab. Heparin 0-7 coagulation factor X Homo sapiens 31-33 9669748-5 1998 In vitro experiments on the inhibition of factor Xa by TFPI enhanced with native and chemically modified heparins afforded similar results. Heparin 105-113 coagulation factor X Homo sapiens 42-51 9622211-0 1998 Tissue factor pathway inhibitor and anti-FXa kinetic profiles of a new low-molecular-mass heparin, Bemiparin, at therapeutic subcutaneous doses. Heparin 90-97 coagulation factor X Homo sapiens 41-44 9521646-1 1998 Regulation of the inhibitory activity of antithrombin, the principal inhibitor of the blood-clotting proteinases factor Xa and thrombin, is accomplished by binding to heparin. Heparin 167-174 coagulation factor X Homo sapiens 113-122 9521646-3 1998 By derivatization of this cysteine with a bulky group, fluorescein, the antithrombin became permanently and fully activated toward reaction with factor Xa in a manner analogous to heparin activation, albeit as a substrate. Heparin 180-187 coagulation factor X Homo sapiens 145-154 9521646-4 1998 These findings establish a structural basis for the mechanism of heparin activation of antithrombin against factor Xa in agreement with that proposed from an X-ray structure of antithrombin. Heparin 65-72 coagulation factor X Homo sapiens 108-117 9622211-1 1998 Low-molecular-mass heparins (LMMHs) exert an anti-FXa effect through antithrombin III (ATIII) and tissue factor pathway inhibitor (TFPI) displaced from endothelium and lipoproteins. Heparin 19-27 coagulation factor X Homo sapiens 50-53 9187023-2 1997 Heparin augments the inhibitory activity of antithrombin (AT) towards thrombin, factor Xa (FXa) and other activated clotting enzymes. Heparin 0-7 coagulation factor X Homo sapiens 80-89 9541411-1 1998 The binding of heparin causes a conformational change in antithrombin to give an increased heparin binding affinity and activate the inhibition of thrombin and factor Xa. Heparin 15-22 coagulation factor X Homo sapiens 160-169 9187023-2 1997 Heparin augments the inhibitory activity of antithrombin (AT) towards thrombin, factor Xa (FXa) and other activated clotting enzymes. Heparin 0-7 coagulation factor X Homo sapiens 91-94 9187023-3 1997 Tissue factor pathway inhibitor (TFPI) is an endogenous heparin releasable three domain Kunitz-type coagulation inhibitor which inhibits the crucial tissue factor-factor VIIa (TF-FVIIa) dependent coagulation pathway in the presence of FXa. Heparin 56-63 coagulation factor X Homo sapiens 235-238 8840000-2 1996 Previous studies have shown that heparin binds to TFPI at two sites and enhances the inhibitory activity of TFPI towards factor Xa. Heparin 33-40 coagulation factor X Homo sapiens 121-130 9058215-10 1997 Protamine titration (Hepcon) correlated with the factor Xa inhibitory assay for heparin (r2 = 0.76). Heparin 80-87 coagulation factor X Homo sapiens 49-58 8980646-7 1996 Apparent second-order rate constant (ki) for the inhibition of factor Xa by PAI-1 at 5 mM Ca2+ was 1.6 x 10(4) M-1 s-1, and was enhanced 3-fold by 2 u/ml of heparin (4.6 x 10(4) M-1 s-1) and 10-fold by 100 nM vitronectin (1.6 x 10(5) M-1 s-1), respectively. Heparin 157-164 coagulation factor X Homo sapiens 63-72 8837315-4 1996 After the rapid disappearance of the h-rTFPI complex from plasma, an intravenous injection of heparin resulted in a release of h-rTFPI/factor Xa complex into plasma. Heparin 94-101 coagulation factor X Homo sapiens 135-144 8837315-5 1996 However, the recovery of heparin-releasable h-rTFPI/factor Xa decreased significantly in a time-dependent manner. Heparin 25-32 coagulation factor X Homo sapiens 52-61 8679610-2 1996 A heparin-induced conformational change is required to convert antithrombin from a slow to a fast inhibitor of factor Xa. Heparin 2-9 coagulation factor X Homo sapiens 111-120 8679610-7 1996 1, 423-425] that the reactive center residue P14 is inserted into beta-sheet A in native antithrombin and is displaced from the beta-sheet by heparin binding, thereby altering the conformation of the reactive center and making it a better target for factor Xa binding. Heparin 142-149 coagulation factor X Homo sapiens 250-259 8910598-1 1996 The binding of heparin to antithrombin greatly accelerates the rate of inhibition of the target proteinases thrombin and factor Xa. Heparin 15-22 coagulation factor X Homo sapiens 121-130 8910598-2 1996 Acceleration of the rate of inhibition of factor Xa involves a conformational change in antithrombin that is translated from the heparin binding site to the reactive center loop. Heparin 129-136 coagulation factor X Homo sapiens 42-51 8840000-6 1996 Heparin enhanced the inhibitory activity of TFPI towards factor Xa even in the presence of factor VIIa-tissue factor complexes in solution phase. Heparin 0-7 coagulation factor X Homo sapiens 57-66 8651503-4 1996 The biological activity of the immobilized heparin (or hydrolyzed heparin) was measured in terms of its inactivation of blood coagulation factor Xa. Heparin 43-50 coagulation factor X Homo sapiens 138-147 8651503-4 1996 The biological activity of the immobilized heparin (or hydrolyzed heparin) was measured in terms of its inactivation of blood coagulation factor Xa. Heparin 66-73 coagulation factor X Homo sapiens 138-147 8651503-5 1996 It was found that the covalently anchored hydrolyzed heparin was not biologically active, but the immobilized heparin was able to inactivate factor Xa. Heparin 110-117 coagulation factor X Homo sapiens 141-150 7495073-0 1995 Inhibition of prothrombinase by antithrombin-heparin at a macroscopic surface. Heparin 45-52 coagulation factor X Homo sapiens 14-28 8634431-3 1996 When factor Xa is added to mixtures containing TFPI, prothrombin, calcium ions, and nonactivated platelets or factor V and phospholipids, TFPI significantly reduces subsequent thrombin generation, and the inhibitory effect is enhanced by heparin. Heparin 238-245 coagulation factor X Homo sapiens 5-14 8634431-4 1996 If factor Xa is preincubated with calcium ions and thrombin-activated platelets or factor Va and phospholipids to permit formation of prothrombinase before the addition of prothrombin and physiologic concentrations of TFPI (< 8 nmol/L), minimal inhibition of thrombin generation occurs, even in the presence of heparin. Heparin 314-321 coagulation factor X Homo sapiens 3-12 8907299-4 1996 Heparins exert their anticoagulant effect by enhancing ATIII inhibitory action on factor Xa and thrombin, which results in decreased factor X activation, prothrombinase formation, prothrombin activation and thrombin generation. Heparin 0-8 coagulation factor X Homo sapiens 82-91 7727433-0 1995 Effect of heparin on the inhibition of factor Xa by tissue factor pathway inhibitor: a segment, Gly212-Phe243, of the third Kunitz domain is a heparin-binding site. Heparin 10-17 coagulation factor X Homo sapiens 39-48 7727433-0 1995 Effect of heparin on the inhibition of factor Xa by tissue factor pathway inhibitor: a segment, Gly212-Phe243, of the third Kunitz domain is a heparin-binding site. Heparin 143-150 coagulation factor X Homo sapiens 39-48 7495073-9 1995 The heparin-independent inhibition of prothrombinase by antithrombin (4 microM) in the presence of prothrombin (0.2 microM) was virtually negligible. Heparin 4-11 coagulation factor X Homo sapiens 38-52 7753456-0 1995 Monitoring of heparins in haemodialysis using an anti-factor-Xa-specific whole-blood clotting assay. Heparin 14-22 coagulation factor X Homo sapiens 54-63 8589511-3 1995 Cleaved, low affinity heparin (C-heparin) with factor Xa inhibition activity of 107 to 130 IU/mg, was prepared by partial deaminative cleavage of commercial crude heparin, and high-affinity heparin (HA-heparin) with factor Xa inhibition activity of 550 to 1000 IU/mg was prepared by fractionation of C-heparin using agarose-ATIII affinity chromatography. Heparin 22-29 coagulation factor X Homo sapiens 47-56 8589511-3 1995 Cleaved, low affinity heparin (C-heparin) with factor Xa inhibition activity of 107 to 130 IU/mg, was prepared by partial deaminative cleavage of commercial crude heparin, and high-affinity heparin (HA-heparin) with factor Xa inhibition activity of 550 to 1000 IU/mg was prepared by fractionation of C-heparin using agarose-ATIII affinity chromatography. Heparin 22-29 coagulation factor X Homo sapiens 216-225 8589511-3 1995 Cleaved, low affinity heparin (C-heparin) with factor Xa inhibition activity of 107 to 130 IU/mg, was prepared by partial deaminative cleavage of commercial crude heparin, and high-affinity heparin (HA-heparin) with factor Xa inhibition activity of 550 to 1000 IU/mg was prepared by fractionation of C-heparin using agarose-ATIII affinity chromatography. Heparin 33-40 coagulation factor X Homo sapiens 47-56 8589511-3 1995 Cleaved, low affinity heparin (C-heparin) with factor Xa inhibition activity of 107 to 130 IU/mg, was prepared by partial deaminative cleavage of commercial crude heparin, and high-affinity heparin (HA-heparin) with factor Xa inhibition activity of 550 to 1000 IU/mg was prepared by fractionation of C-heparin using agarose-ATIII affinity chromatography. Heparin 33-40 coagulation factor X Homo sapiens 47-56 8589511-3 1995 Cleaved, low affinity heparin (C-heparin) with factor Xa inhibition activity of 107 to 130 IU/mg, was prepared by partial deaminative cleavage of commercial crude heparin, and high-affinity heparin (HA-heparin) with factor Xa inhibition activity of 550 to 1000 IU/mg was prepared by fractionation of C-heparin using agarose-ATIII affinity chromatography. Heparin 33-40 coagulation factor X Homo sapiens 47-56 8589511-5 1995 Anticoagulant activity of the heparin immobilized surfaces was determined by chromogenic assay for the inhibition of factor Xa. Heparin 30-37 coagulation factor X Homo sapiens 117-126 8280781-0 1994 Arg-129 plays a specific role in the conformation of antithrombin and in the enhancement of factor Xa inhibition by the pentasaccharide sequence of heparin. Heparin 148-155 coagulation factor X Homo sapiens 92-101 7992254-1 1994 The common unfractionated heparin preparations (UFH) accelerate inhibition of most of the enzymes in the coagulation cascade, while low-molecular mass heparin (LMMH) mainly accelerates inhibition of activated coagulation factor X (FXa). Heparin 151-158 coagulation factor X Homo sapiens 209-229 7992254-5 1994 At a heparin concentration of 0.5 or 1.0 FXa-inhibiting IU/ml, the formation of TAT and FPA was substantial and always much more increased with LMMH than with UFH. Heparin 5-12 coagulation factor X Homo sapiens 41-44 8029789-6 1994 The results thus suggest that the Factor Xa-based antithrombin III activity method provides more valid results in patients on heparin therapy. Heparin 126-133 coagulation factor X Homo sapiens 34-43 7740455-7 1994 At concentrations which doubled the clotting time of contact-activated normal plasma, heparin and three low Mr heparins also abrogated prothrombin activation initiated with 0.5 nM factor Xa, but not with 5 nM factor Xa. Heparin 111-119 coagulation factor X Homo sapiens 180-189 7740455-10 1994 When 5 or 10 pM relipidated r-human tissue factor and CaCl2 were added to normal plasma, heparin and the three low Mr heparins delayed the onset of prothrombin activation until the concentration of factor Xa generated exceeded 1 nM, and they subsequently inhibited prothrombin activation to the same extent. Heparin 89-96 coagulation factor X Homo sapiens 198-207 7918495-0 1994 Kinetics of the inhibition of factor Xa and the tissue factor-factor VIIa complex by the tissue factor pathway inhibitor in the presence and absence of heparin. Heparin 152-159 coagulation factor X Homo sapiens 30-39 7932105-2 1994 We described an amidolytic method for determining the anticoagulant activity of commercially available low molecular-weight heparin (LMWH) with the use of factor Xa (FXa) and thrombin (FIIa), and a chromogenic peptidyl substrate, S-2222 or S-2238. Heparin 124-131 coagulation factor X Homo sapiens 155-164 7932105-2 1994 We described an amidolytic method for determining the anticoagulant activity of commercially available low molecular-weight heparin (LMWH) with the use of factor Xa (FXa) and thrombin (FIIa), and a chromogenic peptidyl substrate, S-2222 or S-2238. Heparin 124-131 coagulation factor X Homo sapiens 166-169 8054461-6 1994 It was concluded that at least twice the dose of Fragmin (anti-FXa), compared with heparin, was required, suggesting that thrombin inhibition is crucial for the antithrombotic efficacy of heparin in CPB circuits. Heparin 188-195 coagulation factor X Homo sapiens 63-66 8029801-2 1994 We used this model to test the antithrombotic activity of the prothrombinase complex inhibitors factor rXai and its chemical analog glutamyl-glycyl-arginyl chloromethyl ketone inactivated human factor Xa (EGR-Xai), along with the thrombin inhibitors D-phenylalanyl-prolyl-arginyl chloromethyl ketone (PPACK) and heparin. Heparin 312-319 coagulation factor X Homo sapiens 194-203 7899863-1 1994 Anti-Factor Xa methods have been generally accepted for the monitoring of heparin treatment, mainly due to their sensitivity to LMW heparin and excellent performance on automated equipment. Heparin 74-81 coagulation factor X Homo sapiens 5-14 7899863-1 1994 Anti-Factor Xa methods have been generally accepted for the monitoring of heparin treatment, mainly due to their sensitivity to LMW heparin and excellent performance on automated equipment. Heparin 132-139 coagulation factor X Homo sapiens 5-14 8262929-11 1993 At optimal concentrations, the major mechanism of heparin action is also a reduction in the Ki of the initial encounter complex between factor Xa and rTFPI. Heparin 50-57 coagulation factor X Homo sapiens 136-145 8388347-5 1993 Heparin increases the rate of inactivation of FXa and of tissue factor-F VIIa by TFPI. Heparin 0-7 coagulation factor X Homo sapiens 46-49 8128425-3 1993 As an alternative we define a unit of heparin in terms of anti-factor Xa- and antithrombin-activity that is independent of the heparin standard and of the assay method, but that is based upon a quantitative description of the catalytic effect of heparin on AT III mediated thrombin- and factor Xa breakdown. Heparin 38-45 coagulation factor X Homo sapiens 63-72 8128425-3 1993 As an alternative we define a unit of heparin in terms of anti-factor Xa- and antithrombin-activity that is independent of the heparin standard and of the assay method, but that is based upon a quantitative description of the catalytic effect of heparin on AT III mediated thrombin- and factor Xa breakdown. Heparin 38-45 coagulation factor X Homo sapiens 287-296 8128425-4 1993 Expression of the results of existing anti-factor Xa- and antithrombin tests in terms of these units will allow to express heparin levels in plasma in terms of concentrations of active anticoagulant material. Heparin 123-130 coagulation factor X Homo sapiens 43-52 8292716-6 1993 Heparin and Ca2+ together, but not individually, enhance the rate of factor Xa inhibition by full-length TFPI. Heparin 0-7 coagulation factor X Homo sapiens 69-78 8292716-7 1993 The effect of heparin is concentration dependent and biphasic (maximal between 0.1 and 1.0 unit/ml) suggesting that the acceleration of factor Xa inhibition occurs at least in part through a "template" mechanism. Heparin 14-21 coagulation factor X Homo sapiens 136-145 8408111-3 1993 High affinity heparin oligosaccharides (HA-heparin, anti-factor Xa activity of 592 +/- 120 IU/mg) prepared by partial deaminative cleavage of commercial crude heparin and fractionated by agarose-ATIII affinity chromatography, were immobilized to surface-modified PE by reductive amination. Heparin 14-21 coagulation factor X Homo sapiens 57-66 1321995-1 1992 The binding ability of low molecular weight heparin (FR-860), and conventional unfractionated heparin (UF-heparin) to factor Xa (F.Xa), thrombin and AT III was investigated using FR-860- and UF-heparin-Sepharoses. Heparin 44-51 coagulation factor X Homo sapiens 118-127 8362270-1 1993 Anti-factor Xa methods have been generally accepted for the monitoring of heparin treatment mainly due to their sensitivity to LMWH and excellent performance on automated equipment. Heparin 74-81 coagulation factor X Homo sapiens 5-14 8395736-0 1993 Anti-factor Xa determination in blood: a new method for controlling heparin therapy. Heparin 68-75 coagulation factor X Homo sapiens 5-14 1618758-7 1992 In contrast, the full-length heparin produced large ionic strength-dependent enhancements in second order rate constants for both antithrombin reactions of 4,300-fold for thrombin and 580-fold for factor Xa at I 0.15. Heparin 29-36 coagulation factor X Homo sapiens 197-206 8362268-3 1993 In the plasma-based assays, heparin exhibited strong inhibition in both thrombin and Factor Xa-based assays, whereas pentasaccharide was only active in Factor Xa-based assays and lactobionic acid was only active in thrombin-based assays. Heparin 28-35 coagulation factor X Homo sapiens 85-94 8362268-4 1993 In the AT III supplemented systems, heparin was able to inhibit strongly both Factor Xa and thrombin, while pentasaccharide could only inhibit Factor Xa. Heparin 36-43 coagulation factor X Homo sapiens 78-87 1503326-14 1992 CONCLUSION: Low-molecular-weight heparinoid, given in a fixed dose of 750 anti-factor Xa units subcutaneously twice daily, is more effective than subcutaneous low-dose heparin for the prevention of deep vein thrombosis in patients with acute ischemic stroke. Heparin 33-40 coagulation factor X Homo sapiens 79-88 1412157-6 1992 The (absence of) inhibition of prothrombin conversion by prothrombinase in the presence of heparins found with the previous method is also found using the new algorithm. Heparin 91-99 coagulation factor X Homo sapiens 57-71 1322691-2 1992 The anti-factor Xa and anti-thrombin activities were measured directly, by assessing the heparin-dependent pseudo-first order rate constants of inactivation of human factor Xa or thrombin. Heparin 89-96 coagulation factor X Homo sapiens 166-175 1322691-5 1992 That is, 1.5 mM calcium stimulated the UF standard heparin-catalysed inactivation of factor Xa 2.1-2.4 times. Heparin 51-58 coagulation factor X Homo sapiens 85-94 1322691-7 1992 Thus, the largest effects of calcium in the inactivation reaction of factor Xa is seen with UF standard heparin. Heparin 104-111 coagulation factor X Homo sapiens 69-78 1321995-1 1992 The binding ability of low molecular weight heparin (FR-860), and conventional unfractionated heparin (UF-heparin) to factor Xa (F.Xa), thrombin and AT III was investigated using FR-860- and UF-heparin-Sepharoses. Heparin 94-101 coagulation factor X Homo sapiens 118-127 1321995-1 1992 The binding ability of low molecular weight heparin (FR-860), and conventional unfractionated heparin (UF-heparin) to factor Xa (F.Xa), thrombin and AT III was investigated using FR-860- and UF-heparin-Sepharoses. Heparin 94-101 coagulation factor X Homo sapiens 118-127 1663665-2 1991 With the help of a combined assay method heparin characterization is made possible using the TAT/XAT quotient under consideration of the simultaneous inhibition of the two serine proteases thrombin and factor Xa by antithrombin III. Heparin 41-48 coagulation factor X Homo sapiens 202-211 1579892-1 1992 Using biochemically defined conditions on a fast kinetic centrifugal analyzer the effect of recombinant hirudin (rH) and unfractionated heparin (UH) on thrombin and factor Xa generation was investigated. Heparin 136-143 coagulation factor X Homo sapiens 165-174 1326098-3 1992 It is taken into account that the fraction of a low molecular heparin that binds with high affinity to antithrombin III contains two fundamentally different components: the material above the critical chain-length of 17 sugar units that has both anti-factor Xa activity and antithrombin activity (ACLM) and the material below that length with anti-factor Xa activity only (BCLM). Heparin 62-69 coagulation factor X Homo sapiens 251-260 1326098-3 1992 It is taken into account that the fraction of a low molecular heparin that binds with high affinity to antithrombin III contains two fundamentally different components: the material above the critical chain-length of 17 sugar units that has both anti-factor Xa activity and antithrombin activity (ACLM) and the material below that length with anti-factor Xa activity only (BCLM). Heparin 62-69 coagulation factor X Homo sapiens 348-357 1665594-3 1991 Pseudo-first order rate constants of inactivation of factor Xa and thrombin by antithrombin III were determined as function of heparin concentration, in the presence of 4.0 mM CaCl2. Heparin 127-134 coagulation factor X Homo sapiens 53-62 1665594-6 1991 Analysis of CY216 subfractions, obtained by gel filtration, showed that the heparin molecules of the upper region of the molecular weight distribution are responsible for the anti-thrombin, but also to a large extent for the anti-factor Xa activities. Heparin 76-83 coagulation factor X Homo sapiens 230-239 1665594-0 1991 Low molecular weight heparin-catalyzed inactivation of factor Xa and thrombin by antithrombin III--effect of platelet factor 4. Heparin 21-28 coagulation factor X Homo sapiens 55-64 2268268-11 1990 Heparin prolonged by 15 s and 45 s the time required to demonstrate Factor V activation in CAP supplemented with Factor Xa and thrombin respectively. Heparin 0-7 coagulation factor X Homo sapiens 113-122 2070046-1 1991 Inhibition of prothrombinase by antithrombin III (ATIII) and heparin was investigated in a continuous-flow system. Heparin 61-68 coagulation factor X Homo sapiens 14-28 2070046-9 1991 Unfractionated heparin and an ultra-low molecular weight heparin (pentasaccharide) did enhance the ATIII-dependent neutralization of prothrombinase, but to a much lesser extent than observed with small unilaminar phospholipid vesicles as the catalytic sites for prothrombinase assembly. Heparin 15-22 coagulation factor X Homo sapiens 133-147 2070046-9 1991 Unfractionated heparin and an ultra-low molecular weight heparin (pentasaccharide) did enhance the ATIII-dependent neutralization of prothrombinase, but to a much lesser extent than observed with small unilaminar phospholipid vesicles as the catalytic sites for prothrombinase assembly. Heparin 15-22 coagulation factor X Homo sapiens 262-276 2070046-9 1991 Unfractionated heparin and an ultra-low molecular weight heparin (pentasaccharide) did enhance the ATIII-dependent neutralization of prothrombinase, but to a much lesser extent than observed with small unilaminar phospholipid vesicles as the catalytic sites for prothrombinase assembly. Heparin 57-64 coagulation factor X Homo sapiens 133-147 2070046-9 1991 Unfractionated heparin and an ultra-low molecular weight heparin (pentasaccharide) did enhance the ATIII-dependent neutralization of prothrombinase, but to a much lesser extent than observed with small unilaminar phospholipid vesicles as the catalytic sites for prothrombinase assembly. Heparin 57-64 coagulation factor X Homo sapiens 262-276 2070046-10 1991 The findings reported here support the notion that regulation of prothrombinase by heparin under in vivo conditions occurs at the stage of its formation, ie, through inhibition of free factor Xa and/or the generation of factor Va, rather than by direct inhibition of the prothrombinase activity. Heparin 83-90 coagulation factor X Homo sapiens 65-79 2070046-10 1991 The findings reported here support the notion that regulation of prothrombinase by heparin under in vivo conditions occurs at the stage of its formation, ie, through inhibition of free factor Xa and/or the generation of factor Va, rather than by direct inhibition of the prothrombinase activity. Heparin 83-90 coagulation factor X Homo sapiens 271-285 1718949-5 1991 A kinetical study demonstrated that rat factor Xa was strongly inhibited by rat antithrombin III, with a Ki of 2.2 x 10(-11) M, in the presence of heparin. Heparin 147-154 coagulation factor X Homo sapiens 40-49 1718949-6 1991 However, in the absence of heparin, the second order rate constant for the inhibition of rat factor Xa by rat antithrombin III was 2.6 x 10(4) M-1.min-1, which was one forty-third that for the inhibition of human factor Xa by human antithrombin III. Heparin 27-34 coagulation factor X Homo sapiens 93-102 1706595-1 1991 This protein is known to be involved in processes that follow platelet stimulation, specifically, in the binding of heparin (interfering with the heparin-mediated inhibition of thrombin and Factor Xa by antithrombin III), in the growth of endothelial cells and in fibrinolysis. Heparin 116-123 coagulation factor X Homo sapiens 190-199 1706595-1 1991 This protein is known to be involved in processes that follow platelet stimulation, specifically, in the binding of heparin (interfering with the heparin-mediated inhibition of thrombin and Factor Xa by antithrombin III), in the growth of endothelial cells and in fibrinolysis. Heparin 146-153 coagulation factor X Homo sapiens 190-199 2268268-17 1990 The availability of Factor Xa markedly moderates the ability of heparin to inhibit Factor V activation. Heparin 64-71 coagulation factor X Homo sapiens 20-29 2160449-9 1990 However, the acceleration by heparin or dextran sulfate for the inhibition of Factor Xa, Factor XIa, and plasma kallikrein was not significant. Heparin 29-36 coagulation factor X Homo sapiens 78-87 1658965-1 1991 In determining heparin one has the choice to test a specific activity, such as the decay constant of thrombin or factor Xa on a global test such as the aPTT. Heparin 15-22 coagulation factor X Homo sapiens 113-122 2248954-1 1990 Factor Xa modified by reductive methylation (greater than 92%) loses the capacity to bind heparin as determined both by gel chromatography and by sedimentation equilibrium ultracentrifugation. Heparin 90-97 coagulation factor X Homo sapiens 0-9 2248954-5 1990 These findings provide direct evidence that the interaction of factor Xa with heparin is not involved in the heparin-enhanced inhibition of this enzyme. Heparin 78-85 coagulation factor X Homo sapiens 63-72 1964634-11 1990 After intravenous administration of low molecular weight heparin, the half-life of the anti-factor Xa activity is considerably longer than for unfractionated heparin, while the anti-factor IIa half-lives are similar. Heparin 57-64 coagulation factor X Homo sapiens 92-101 2394942-0 1990 The importance of anti-factor Xa and antithrombin activities of low molecular weight heparins. Heparin 85-93 coagulation factor X Homo sapiens 23-32 2166377-1 1990 Since low molecular weight heparin is used for the prevention of thromboembolism, the coagulation laboratories are in need of a simple, reliable and practicable test for factor Xa inhibition in order to monitor the effect of low molecular heparin in plasma. Heparin 27-34 coagulation factor X Homo sapiens 170-179 2164262-0 1990 The inhibition of intrinsic prothrombinase and its generation by heparin and four derivatives in prothrombin poor plasma. Heparin 65-72 coagulation factor X Homo sapiens 28-42 2164262-1 1990 The effect of different heparins and a synthetic pentasaccharide on the inhibition of intrinsic prothrombinase and of its generation was studied by a new technique, using a defibrinated prothrombin poor human plasma, supplemented with phospholipids and calcium. Heparin 24-32 coagulation factor X Homo sapiens 96-110 2164262-9 1990 On the other hand, anti-IIa activity of heparins could be responsible for the inhibition of prothrombinase generation. Heparin 40-48 coagulation factor X Homo sapiens 92-106 2174783-6 1990 The peak heparin concentration on Day 2 ranged from 0.40 to 0.75 anti-FXa U/ml and adjustment was only required in 3 patients. Heparin 9-16 coagulation factor X Homo sapiens 70-73 1963017-1 1990 Unfractionated heparin in the extrinsic system has an action on prothrombinase that is insignificant compared to its antithrombin action. Heparin 15-22 coagulation factor X Homo sapiens 64-78 1963018-2 1990 The plasmatic anti-Factor Xa activity half-life, whatever the injected dose of the different low molecular weight heparins, is about two to four times longer than for unfractionated heparin while anti-Factor IIa plasmatic half-life is only slightly longer for enoxaparin than for unfractionated heparin. Heparin 114-122 coagulation factor X Homo sapiens 19-28 1963018-2 1990 The plasmatic anti-Factor Xa activity half-life, whatever the injected dose of the different low molecular weight heparins, is about two to four times longer than for unfractionated heparin while anti-Factor IIa plasmatic half-life is only slightly longer for enoxaparin than for unfractionated heparin. Heparin 114-121 coagulation factor X Homo sapiens 19-28 2155017-3 1990 The LMW heparin dose necessary (anti FXa-activity) for effective anticoagulation was two thirds of the standard heparin dose. Heparin 8-15 coagulation factor X Homo sapiens 37-40 34816442-2 2022 This study aimed to: (i) develop a PK/PD model for UFH, quantified by anti-factor Xa assay and the UFH effect measured by activated partial thromboplastin time (aPTT) (ii) evaluate pediatric UFH infusions in achieving anti-factor Xa (0.3 - 0.7 IU/mL) therapeutic target by simulations. Heparin 51-54 coagulation factor X Homo sapiens 75-84 22374861-4 2012 Heparin was given at prophylactic dosage in patients at low risk and at fixed subtherapeutic doses (3,800 or 4,000 UI anti-FXa, b.i.d.) Heparin 0-7 coagulation factor X Homo sapiens 123-126 2083864-3 1990 Heparin subcutaneously (200 U/kg) injected for 2 weeks resulted in an enhanced inactivation of thrombin and factor Xa by the endothelium. Heparin 0-7 coagulation factor X Homo sapiens 108-117 33588972-5 2021 RESULTS: The percentage of anti-factor Xa levels outside therapeutic range was lower in the subcutaneous low-molecular-weight heparin group compared with the percentage of activated partial thromboplastin times outside therapeutic range in the intravenous unfractionated heparin group (40% versus 90%, p < 0.001). Heparin 126-133 coagulation factor X Homo sapiens 32-41 34287985-8 2022 The prolongation of INR was related to the high heparin level in the perfusate (anti-FXa > 3 U/ml). Heparin 48-55 coagulation factor X Homo sapiens 85-88 34725832-2 2022 The objective of this study was to evaluate the effectiveness and safety of two anticoagulation protocols using conventional (0.3-0.7 IU/mL) vs. restricted (0.2-0.5 IU/mL) anti-factor Xa (anti-Xa) targets for the management of unfractionated heparin (UFH) in adult ECMO patients. Heparin 251-254 coagulation factor X Homo sapiens 177-186 34816442-2 2022 This study aimed to: (i) develop a PK/PD model for UFH, quantified by anti-factor Xa assay and the UFH effect measured by activated partial thromboplastin time (aPTT) (ii) evaluate pediatric UFH infusions in achieving anti-factor Xa (0.3 - 0.7 IU/mL) therapeutic target by simulations. Heparin 191-194 coagulation factor X Homo sapiens 75-84 34816442-2 2022 This study aimed to: (i) develop a PK/PD model for UFH, quantified by anti-factor Xa assay and the UFH effect measured by activated partial thromboplastin time (aPTT) (ii) evaluate pediatric UFH infusions in achieving anti-factor Xa (0.3 - 0.7 IU/mL) therapeutic target by simulations. Heparin 191-194 coagulation factor X Homo sapiens 223-232 34816442-10 2022 In conclusion, the UFH anti-factor Xa target is not achieved initially especially in young pediatrics, suggesting the need to optimize UFH dosing to achieve higher therapeutic success. Heparin 19-22 coagulation factor X Homo sapiens 28-37 34816442-2 2022 This study aimed to: (i) develop a PK/PD model for UFH, quantified by anti-factor Xa assay and the UFH effect measured by activated partial thromboplastin time (aPTT) (ii) evaluate pediatric UFH infusions in achieving anti-factor Xa (0.3 - 0.7 IU/mL) therapeutic target by simulations. Heparin 51-54 coagulation factor X Homo sapiens 223-232 35200221-4 2022 Using a routine hybrid heparin anti-Factor Xa assay, 1 patient demonstrated a strong linear correlation up to a serum rivaroxaban concentration of 940 ng/mL. Heparin 23-30 coagulation factor X Homo sapiens 36-45 34428806-3 2021 Anti-factor Xa (aFXa) level is a measure of unfractionated heparin efficacy and safety. Heparin 59-66 coagulation factor X Homo sapiens 5-14 34205548-9 2021 In this study, we illustrate the performances of different anti-FXa assays used for testing heparin on UFH or LMWH treated patients" plasmas and obtained using citrate or CTAD anticoagulants. Heparin 92-99 coagulation factor X Homo sapiens 64-67 35551912-2 2022 ZPI is also activated by heparin to inhibit free FXa at a physiologically significant rate. Heparin 25-32 coagulation factor X Homo sapiens 49-52 35551912-8 2022 Together, these findings suggest that heparin binding to a site on ZPI extending from helix C to helix H promotes ZPI inhibition of FXa and allosterically antagonizes PZ binding to ZPI through long-range conformational changes. Heparin 38-45 coagulation factor X Homo sapiens 132-135 35551912-9 2022 Heparin antagonism of PZ binding to ZPI may serve to spare limiting PZ and allow PZ and heparin cofactors to target FXa at different sites of action. Heparin 0-7 coagulation factor X Homo sapiens 116-119 35551912-9 2022 Heparin antagonism of PZ binding to ZPI may serve to spare limiting PZ and allow PZ and heparin cofactors to target FXa at different sites of action. Heparin 88-95 coagulation factor X Homo sapiens 116-119 34604133-9 2021 Results: Anti-factor Xa levels showed a moderate correlation with heparin dose, whereas the other tests showed a weak correlation. Heparin 66-73 coagulation factor X Homo sapiens 14-23 34604133-13 2021 Conclusions: Anti-factor Xa levels correlate better to heparin dose than activated clotting time. Heparin 55-62 coagulation factor X Homo sapiens 18-27 34604133-14 2021 The use of anti-factor Xa assay instead of activated clotting time for dosing of unfractionated heparin could reduce thrombotic complications in neonates with congenital diaphragmatic hernia on ECMO support. Heparin 96-103 coagulation factor X Homo sapiens 16-25 35456329-6 2022 Both agents allowed for accurate measurement of anti-factor Xa activity in the plasma containing rivaroxaban and heparins in the concentration range reached in patients" blood. Heparin 113-120 coagulation factor X Homo sapiens 53-62 34655821-2 2022 The ability to monitor low-molecular-weight heparin by obtaining anti-factor Xa (anti-Xa) serum levels provides an opportunity to evaluate safety and efficacy. Heparin 44-51 coagulation factor X Homo sapiens 70-79