A Hitherto Undescribed Naturally Occurring Plasma Antagonist of Activated Factor X Inhibitor (Antithrombin III)

1979 ◽  
Author(s):  
E. T. Yin ◽  
W. J. Salsgiver ◽  
O. Tangen
Keyword(s):  
Equilibrium State ◽  
Human Plasma ◽  
Antithrombin Iii ◽  
Circumstantial Evidence ◽  
Incubation Mixture ◽  
Factor X ◽  
Normal Human Plasma ◽  
Plasma Component ◽  
Naturally Occurring ◽  
Normal Human

Circumstantial evidence suggested that normal human plasma contained a substance regulating the neutralization of F.Xa by F.Xa inhibitor(XaI), (Yin et.al.,Adv.Exper. Med. & Biol., 52 : 239, 1975, Plenum Press, N.Y.).This plasma component has now been isolated and partially purified in our laboratory, and tentatively designated as “Anti-XaI”.In experiments employing purified components, when Anti-XaI was incubated at 37°C with F.Xa, Xal and heparin for two minutes at pH7.5, the amount of F.Xa inhibited was inversely proportional to the Anti-XaI concentration. But, when the F.Xa was replaced by thrombin in the incubation mixture, the neutralization of thrombin clotting activity was undisturbed.Anti-XaI was found to be neither PF3 nor PF4.These and other data strongly suggest that the “Antithrombin III pathway” is more complex than currently believed to be. In circulating blood an equilibrium state must exist between Anti-XaI and XaI.Under certain conditions when the Anti-XaI activity is predominant the rate of F.Xa neutralization bv XaI then becomes slower than the activation of prothrombin to thrombin by F.Xa.

A Hitherto Undescribed Naturally Occurring Plasma Antagonist of Activated Factor X Inhibitor (Antithrombin III)

1979 ◽  
Author(s):  
E.T. Yin ◽  
W.J. Salsgiver ◽  
O. Tangen
Keyword(s):  
Equilibrium State ◽  
Human Plasma ◽  
Antithrombin Iii ◽  
Circumstantial Evidence ◽  
Incubation Mixture ◽  
Factor X ◽  
Normal Human Plasma ◽  
Plasma Component ◽  
Naturally Occurring ◽  
Normal Human

Circumstantial evidence suggested that normal human plasma contained a substance regulating the neutralization of F. Xa by F. Xa inhibitor (XaI), (Yin et.al., Adv. Exper. Med.& Biol., 52: 239, 1975, Plenum Press, N.Y.).This plasma component has now been isolated and partially purified in our laboratory, and tentatively designated as “Anti-Xal”.In experiments employing purified components, when Anti-Xal was incubated at 37°C with F. Xa. Xal and heparin for two minutes at pH7.5, the amount of F. Xa inhibited was inversely proportional to the Anti-XaI concentration. But, when the F. Xa was replaced by thrombin in the incubation mixture, the neutralization of thrombin clotting activity was undisturbed. Anti-Xa I was found to be neither PF3 nor PF6.These and other data strongly suggest that the “Antithrombin ill pathway” is more complex than currently believed to be. In circulating blood an equilibrium state must exist between Anti-Xal and Xal. Under certain conditions when the Anti-Xal activity is predominant the rate of F.Xa neutralization by Xal then becomes slower than the activation of prothrombin to thrombin by F.Xa.

A Chromogenic Factor X Assay With New Standardized Reagents

1979 ◽  
Author(s):  
P Friberger ◽  
C Lenne
Keyword(s):  
Human Plasma ◽  
Suitable Method ◽  
Chromogenic Substrate ◽  
Factor X ◽  
Normal Human Plasma ◽  
Normal Plasma ◽  
Normal Human

A recently published method for Factor X (FX) assay (1) utilizing Russel's Viper Venom (RVV) and a chromogenic substrate has been further investigated by testing a large number of parameters. This method has been considered as a suitable method for monitoring coumarol treatment (Bergström et al).The conditions for the activation of FX by purified preparations of the RVV have been studied as well as the conditions for FXa determination with a new chromogenic substrate Bz-Ile-Glu(γ-piperidyl)-Gly-Arg-pNA (S-2337). Both purified factors and normal plasma have been used. The effect of plasma inhibitors as well as the selectivity of the method has been studied.The reproducibility and stability of the different reagents and standards have been studied and found to be good.The amount of FXa activity obtained from normal human plasma has been titrated with FXa inhibitors of known purity.1) Aurell L. et al, Thromb. Res., 11, 595 (1977)2) Bergström et al, Thromb. Res., 12, 531 (1978)

scholarly journals Human antithrombin III heterogeneity

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 229-232 ◽  
Author(s):  
L Williams ◽  
G Murano
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Agarose Gel ◽  
Normal Human Plasma ◽  
Congenital Deficiency ◽  
Single Donor ◽  
At Iii ◽  
Normal Human

Abstract Crossed immunoelectrophoretic patterns were obtained on three patients with a congenital deficiency of anti-thrombin III (AT-III), and on normal single donor and “pooled” plasma controls. In the presence of heparin (incorporated into the agarose gel matrix), the AT-III of normal human plasma was separated into four components: two major, faster-moving components, and two minor, slower-moving components. The three patients with congenital deficiency of AT-III (levels approximately 50% of normal) appeared to possess only one of the faster- moving components, and one of the slower-moving components.

Blood Coagulation Inhibitor in a Snake Plasma (Bothrops jararaca)

1973 ◽  
Vol 30 (01) ◽  
pp. 106-113 ◽  
Author(s):  
Linda Nahas ◽  
Ferruccio Betti ◽  
Aura S. Kamiguti ◽  
Hissae Sato
Keyword(s):  
Human Plasma ◽  
Blood Coagulation ◽  
Antithrombin Iii ◽  
The Other ◽  
Normal Human Plasma ◽  
Clotting Time ◽  
Bovine Thrombin ◽  
Heat Stable ◽  
Coagulation Inhibitor ◽  
Normal Human

SummaryExperiments with plasmas samples from the snake B. jararaca and X. merremii have shown that the two differ markedly with respect to their reaction to bovine thrombin. The plasma of X. merremii appears to react in a manner very similar to that of normal human plasma both using the thrombin clotting test and using the antithrombin III assay of Astrup and Darling (Biggs and Macfariane 1962). The plasma of B. jararaca on the other hand, contains, in addition to antithrombin III, an inhibitor which resembles mammalian heparin. This inhibitor prolongs the thrombin clotting time of human and X. merremii plasmas, is recorded by the antithrombin assay and is neutralized by protamine. The inhibitor is however, not identical with mammalian heparin since it is not adsorbed by BaSO4 and Al(OH)3 (which adsorb heparin) and it is heat labil whereas mammalian heparin is heat stable.

scholarly journals Human antithrombin III heterogeneity

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 229-232
Author(s):  
L Williams ◽  
G Murano
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Agarose Gel ◽  
Normal Human Plasma ◽  
Congenital Deficiency ◽  
Single Donor ◽  
At Iii ◽  
Normal Human

Crossed immunoelectrophoretic patterns were obtained on three patients with a congenital deficiency of anti-thrombin III (AT-III), and on normal single donor and “pooled” plasma controls. In the presence of heparin (incorporated into the agarose gel matrix), the AT-III of normal human plasma was separated into four components: two major, faster-moving components, and two minor, slower-moving components. The three patients with congenital deficiency of AT-III (levels approximately 50% of normal) appeared to possess only one of the faster- moving components, and one of the slower-moving components.

Plasma Inhibition of the Heparin Accelerated Neutralisation of Xa by Antithrombin

1979 ◽  
Author(s):  
I.R. MacGregor ◽  
D.A. Lane ◽  
V.V. Kakkar
Keyword(s):  
Human Plasma ◽  
Synthetic Peptide ◽  
Antithrombin Iii ◽  
Coagulation Factors ◽  
Normal Human Plasma ◽  
Platelet Factor ◽  
Peptide Substrates ◽  
Normal Human ◽  
Heparin Fractions ◽  
Inhibition Of Thrombin

The ability of heparin fractions of different MW (mean MW 8500-30,000) to potentiate the action ot antithrombin III against the coagulation factors thrombin and Xa has been examined in purified reaction mixtures and in plasma. Residual thrombin and Xa have been determined by their peptidase activities against the synthetic peptide substrates H-D-Phe Pip-Arg-pNA and Bz-Ile-Glu-Gly-Arg-pNA. High MW heparin fractions were found to have higher anticoagulant activities than low MW heparin when studied with both thrombin and Xa incubation mixtures in purified mixtures. The inhibition of thrombin by heparin fractions and antithrombin III was unaffected by other plasma components. However, normal human plasma contained a component that inhibited the heparin and antithrombin III inhibition of Xa, particularly when the high MW heparin fraction was used. Experiments using a purified preparation of platelet factor 4 suggested that this platelet derived heparin neutralising protein was not responsible for the inhibition and that a hitherto undescribed inhibitor of heparin action is present in plasma. Preliminary studies have indicated that the inhibitor is concentrated in a fraction rich in lipoprotein and obtained by ultracentrifugation of plasma in high density salt.

A Chromogenic Factor X Assay with New Standardized Reagents

1979 ◽  
Author(s):  
P. Friberger ◽  
C. Lenne
Keyword(s):  
Human Plasma ◽  
Suitable Method ◽  
Chromogenic Substrate ◽  
Factor X ◽  
Normal Human Plasma ◽  
Normal Plasma ◽  
Normal Human

A recently published method for Factor X (FX) assay (1) utilizing Russel’s Viper Venom (RW) and a chromogenic substrate has been further investigated by testing a large number of parameters, This method has been considered as a suitable method for monitoring coumarol treatment (Bergström et al).The conditions for the activation of FX by purified preparations of the RVV have been studied as well as the conditions for FXa determination with a new chromogenic substrate Bz-Ile-Glu(γ-piperidyl)-Gly-Arg-pNA (S-2337). Both purified factors and normal plasma have been used. The effect of plasma inhibitors as well as the selectivity of the method bas been studied.The reproducibility and stability of the different reagents and standards have been studied and found to be good.The amount of FXa activity obtained from normal human plasma has been titrated with FXa inhibitors of known purity.1) Aurell L. et al, Thromb. Res., 11, 595 (1977)2) Bergström et al, Thromb. Res., 12, 531 (1978)

Performances of an Artificial Reagent for the One-stage Factor IX Assay

1975 ◽  
Vol 33 (03) ◽  
pp. 547-552 ◽  
Author(s):  
L Meunier ◽  
J. P Allain ◽  
D Frommel
Keyword(s):  
Human Plasma ◽  
Factor Ix ◽  
Severe Haemophilia ◽  
Normal Human Plasma ◽  
Haemophilia B ◽  
One Stage ◽  
Normal Human ◽  
The One

SummaryA mixture of adsorbed normal human plasma and chicken plasma was prepared as reagent for factor IX measurement using a one-stage method. The substrate was found to be specific for factor IX. Its performances tested on samples displaying factor IX activity ranging from <l%–2,500% compared favorably with those obtained when using the plasma of severe haemophilia B patients as substrate.

Plasma Components which Interfere with Ristocetin-induced Platelet Aggregation

1975 ◽  
Vol 33 (03) ◽  
pp. 540-546 ◽  
Author(s):  
Robert F Baugh ◽  
James E Brown ◽  
Cecil Hougie
Keyword(s):  
Platelet Aggregation ◽  
Human Plasma ◽  
Plasma Proteins ◽  
Binding Protein ◽  
Plasma Heating ◽  
Protein S ◽  
Fold Increase ◽  
Normal Human Plasma ◽  
Preliminary Examination ◽  
Normal Human

SummaryNormal human plasma contains a component or components which interfere with ristocetin-induced platelet aggregation. Preliminary examination suggests a protein (or proteins) which binds ristocetin and competes more effectively for ristocetin than do the proteins involved in ristocetin-induced platelet aggregation. The presence of this protein in normal human plasma also prevents ristocetin-induced precipitation of plasma proteins at levels of ristocetin necessary to produce platelet aggregation (0.5–2.0 mg/ml). Serum contains an apparent two-fold increase of this component when compared with plasma. Heating serum at 56° for one hour results in an additional 2 to 4 fold increase. The presence of a ristocetin-binding protein in normal human plasma requires that this protein be saturated with ristocetin before ristocetin-induced platelet aggregation will occur. Variations in the ristocetin-binding protein(s) will cause apparent discrepancies in ristocetin-induced platelet aggregation in normal human plasmas.

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