The Reaction of Thiol Compounds with the Vitamin-K Dependent Clotting Factors

1969 ◽  
Vol 21 (03) ◽  
pp. 573-579 ◽  
Author(s):  
P Fantl
Keyword(s):  
Prothrombin Time ◽  
Vitamin K ◽  
Anaerobic Conditions ◽  
Clotting Factors ◽  
Thiol Compounds ◽  
Aerobic Conditions ◽  
One Stage ◽  
Factor Ii ◽  
Ph Dependent ◽  
The One

SummaryTreatment of human and dog oxalated plasma with 0.2 to 1.0 × 10−1 M 2.3-dithiopropanol (BAL) or dithiothreitol (DTT) at 2–4° C for 30 min results in the reduction of the vitamin-K dependent clotting factors II, VII, IX and X to the respective-SH derivatives. The reaction is pH dependent. Under aerobic conditions the delayed one stage prothrombin time can be partly reversed. Under anaerobic conditions a gradual prolongation of the one stage prothrombin time occurs without reversal.In very diluted plasma treated with the dithiols, prothrombin can be converted into thrombin if serum as source of active factors VII and X is added. In contrast SH factors VII, IX and X are inactive in the specific tests. Reoxidation to active factors II, VII, IX and X takes place during adsorption and elution of the SH derivatives. The experiments have indicated that not only factor II but also factors VII, IX and X have active-S-S-centres.

Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

1967 ◽  
Vol 18 (01/02) ◽  
pp. 198-210 ◽  
Author(s):  
Ronald S Reno ◽  
Walter H Seegers
Keyword(s):  
Prothrombin Time ◽  
Factor Vii ◽  
Two Stage ◽  
Pronounced Increase ◽  
One Stage ◽  
Assay Procedure ◽  
Bovine Plasma ◽  
The One ◽  
Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

Spectrophotometric Assays of Prothrombin in Plasma of Patients Using Oral Anticoagulants

1979 ◽  
Vol 42 (04) ◽  
pp. 1296-1305 ◽  
Author(s):  
R M Bertina ◽  
W van der Marel-van Nieuwkoop ◽  
E A Loeliger
Keyword(s):  
Prothrombin Time ◽  
Vitamin K ◽  
Oral Anticoagulation ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Factor Xa ◽  
Factor V ◽  
Anticoagulant Treatment ◽  
Factor Ii ◽  
K Deficiency

SummaryTwo spectrophotometric assays for prothrombin have been developed and compared with a one stage coagulant and an immunological assay. One of these assays (called the XAPC assay) uses a combination of factor Xa, phospholipid, Ca2+ and factor V as activator of prothrombin, and measures only normal prothrombin. The second (the ECAR assay) uses Echis carinatus venom as activator. This assay measures both normal prothrombin and PIVKA II (protein induced by vitamin K antagonists/absence). Combination of the results obtained by the XAPC and ECAR assays provides rapid and reliable information on the degree of “subcarboxylation” of prothrombin (oral anticoagulation, vitamin K deficiency).For patients on long term anticoagulant treatment the prothrombin time (Thrombotest) shows better correlation with the ratio prothrombin/prothrombin plus PIVKA II (XAPC/ ECAR) than with the factor II concentration. For patients starting the anticoagulant treatment there is no correlation between the Thrombotest time and the XAPC/ECAR ratio.It seems doubtful that (a) spectrophotometric factor II assay(s) will be as useful as the prothrombin time in the control of oral anticoagulation.

Comparison of the Thrombotest with the One-Stage Prothrombin Time

1961 ◽  
Vol 265 (26) ◽  
pp. 1286-1289 ◽  
Author(s):  
Armand J. Quick ◽  
Clara V. Hussey
Keyword(s):  
Prothrombin Time ◽  
One Stage ◽  
The One

INHERITED FACTOR-VII DEFECT IN A NEGRO FAMILY

PEDIATRICS ◽  
1961 ◽  
Vol 27 (2) ◽  
pp. 204-213
Author(s):  
Helen I. Glueck ◽  
James M. Sutherland
Keyword(s):  
Prothrombin Time ◽  
Factor Vii ◽  
Homozygous State ◽  
Control Value ◽  
One Stage ◽  
First Case ◽  
Severe Deficiency ◽  
Low Levels ◽  
The Difference ◽  
The One

A case of factor-VII deficiency of a congenital nature in a Negro male child has been reported. As far as can be determined, this is the first case reported in this race. The defect was detected at 6 hours of age. Prothrombin, as contrasted to factor VII, after initially low levels normally found in infants, rose to adult levels. The patient's one-stage prothrombin time has ranged between 25 to 35 second (normal 11 to 12 seconds). In spite of this, he has never shown any manifestations of hemorrhage. The patient's family was studied and the findings indicate that the patient's defect represented a homozygous state and that both parents with a less severe deficiency were heterozygous for the trait. The defect is an autosomal disorder directly inherited. It is clinically apparent and easily detected only in the homozygous state. The heterozygous state is characterized by a very slight prolongation of the one-stage prothrombin time, the difference from the control value being so minimal as to be overlooked. In one subject studied, an aunt of the propositus, the quantitative defect (42% of normal) could not be regularly detected by the usual methods. Only by using the plasma of the propositus as the test plasma, was the defect in her plasma detected, thus explaining the transmission of the trait to her offspring. These findings explain the difficulties previously encountered in understanding the inheritance of the disorder.

scholarly journals Prothrombin and the One-stage Prothrombin Time

BMJ ◽  
1955 ◽  
Vol 1 (4919) ◽  
pp. 934-937 ◽  
Author(s):  
A. J. Quick ◽  
C. V. Hussey
Keyword(s):  
Prothrombin Time ◽  
One Stage ◽  
The One

Revised Standardization Method of the One-Stage Prothrombin Time

1987 ◽  
Vol 17 (6) ◽  
pp. 313-320
Author(s):  
Knut Korsbrekke ◽  
Ingebrigt Talstad
Keyword(s):  
Prothrombin Time ◽  
Standardization Method ◽  
One Stage ◽  
The One

Warfarin Induced Fibrinolysis: The Effect Of Recovery With And Without Vitamin K

1981 ◽  
Author(s):  
N A Marsh
Keyword(s):  
Prothrombin Time ◽  
Plasminogen Activator ◽  
Vitamin K ◽  
Dynamic Equilibrium ◽  
Degradation Products ◽  
Direct Action ◽  
Plasma Fibrinogen ◽  
Clotting Factors ◽  
Lysis Time ◽  
Euglobulin Lysis Time

We have previously shown that fibrinolysis in the rat is enhanced by levels of warfarin administration sufficient to produce moderate anticoagulation. This effect is mediated largely by an increase in plasma plasminogen activator. Plasminogen levels are decreased and fibrin(ogen) degradation products raised confirming the presence of a systemic hyperfibrinolytic state. In order to investigate this phenomenon further we have measured fibrinolytic components in rats recovering from warfarin administration. Groups of male Hooded rats received 14 yg warfarin/100 g body weight /day by mouth for one to two weeks. The animals were then allowed to recover without further treatment or following a single 50 μg dose of vitamin K1. Euglobulin lysis time, one stage prothrombin time, plasma plasminogen activator (fibrin plate method), plasma plasminogen (caseinolytic method), plasma fibrinogen (clot weight method) and plasma fibrinolytic inhibitors were measured at intervals after the end of the warfarin treatment. In animals recovering without vitamin K prothrombin time returned to normal within one week. However fibrinolysis remained elevated with plasma plasminogen activator concentrations of more than twice the control value. Plasma inhibitor levels were depressed and fibrinogen levels elevated. After two weeks all fibrinolytic components had returned to normal. Following vitamin Kj administration a different pattern emerged; prothrombin time returned to normal within 24 hours but fibrinolysis was diminished. The latter effect was due to a marked increase in plasma fibrinogen and moderate fall in plasma plasminogen activator both of which contributed to a prolonged euglobulin lysis time. These results indicate that fibrinolysis and coagulation in the rat are not linked in a 'dynamic equilibrium' like that proposed for man. The enhanced fibrinolysis rather than being a result of the fall in vitamin K dependant clotting factors may be due to the direct action of warfarin. The 'fibrinolytic shutdown' following vitamin K remains unexplained .

The Relation between Staphylocoagulase Reacting Factor and Proteins Induced by Vitamin K Absence

1975 ◽  
Author(s):  
B. M. Bas ◽  
A. D. Muller ◽  
H. G. Hemker
Keyword(s):  
Vitamin K ◽  
Vitamin K Antagonists ◽  
The Other ◽  
Two Stage ◽  
One Stage ◽  
Echis Carinatus ◽  
The Difference ◽  
The One ◽  
Factor Assay

Five different ways of estimating prothrombin are applied to the plasma of persons receiving vitamin K antagonists, to know: the one-stage assay, the two-stage assay, the Echis Carinatus Venom assay, the coagulase-reacting factor assay and the immunological assay. The Protein Induced by Vitamin K Absence analogous to prothrombin (PIVKA-II) can be shown to be co-estimated in all but the one-stage assay. There are minor differences, however, between the other four tests. The most practical way to assess both prothrombin and PIVKA-II seems to be the coagulase-reacting factor assay. The difference between the one-stage assay and the others can be explained on basis of the new data on the role of vitamin K in prothrombin biosynthesis. The differences between the other tests are smaller and remain to be explained.

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