Change in tissue thromboplastin content of brain following trauma

SummaryLupus anticoagulants (LA) and anticardiolipin antibodies have been strongly associated with recurrent abortion and fetal death. Because steroids have been reported to improve the fetal outcome of LA associated pregnancies, presumably by decreasing the levels of LA, it becomes desirable to have a simple and reliable test to monitor the levels of the putative antibody. To this effect, we assessed the capacity of the following coagulation tests to detect the presence of LA in serial dilutions of patient plasma with pooled normal plasma: kaolin clotting time (KCT), tissue thromboplastin inhibition test (TTIT), dilute Russell Viper venom time (DRVVT) and activated partial thromboplastin time with standard and high concentrations of phospholipids (SC and HCAPTT). All samples were also evaluated for the presence of anticardiolipin antibodies with an ELISA. The KCT was able to detect LA at a much greater dilution in normal plasma than any of the other clotting assays. The ELISA was comparable to KCT in its ability to detect high dilutions of LA.

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The Activation of Human Factor IX

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647849 ◽

1975 ◽

Vol 33 (03) ◽

pp. 553-563 ◽

Cited By ~ 7

Author(s):

B Østerud ◽

K Laake ◽

H Prydz

Keyword(s):

Molecular Weight ◽

Sodium Dodecyl ◽

Apparent Molecular Weight ◽

Factor Ix ◽

Factor Vii ◽

Activate Factor ◽

Human Factor Ix ◽

Factor Xia ◽

Tissue Thromboplastin ◽

Native Factor

SummaryThe activation of factor IX purified from human plasma has been studied. Factor XIa and kallikrein separately activated factor IX to factor IXa. In both cases factor IX a had an apparent molecular weight of about 42–45000 in sodium dodecyl sul-phate-polyacrylamide disc gel electrophoresis compared with a molecular weight of about 70000 for the native factor IX. The activation by XIa required Ca2+-ions whereas Ca2+-ions did not influence the activation by kallikrein. A mixture of tissue thromboplastin and factor VII or RusselPs-viper venom alone did not activate factor IX. Trypsin activated and plasmin inactivated factor IX.

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Ultrastructural Changes of the Tissue Thromboplastin after Intravenous Injection in Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646670 ◽

1978 ◽

Vol 39 (01) ◽

pp. 201-209 ◽

Cited By ~ 1

Author(s):

Hiroshi Hasegawa ◽

Hiroshi Nagata ◽

Makoto Murao

Keyword(s):

Intravenous Injection ◽

Vascular Endothelium ◽

Model Experiment ◽

Venous Return ◽

Ultrastructural Changes ◽

Membrane Structures ◽

Tissue Thromboplastin ◽

Short Time ◽

Sheet Membrane

SummaryAttempts were made to demonstrate ultrastructural changes of the tissue thromboplastin after intravenous injection, as a model experiment on the pulmonary microthrombi formation induced by the tissue thromboplastin circulating from venous return.Concentrically arranged membrane structures of the injected thromboplastin disappeared in extremely short time after the injection of the thromboplastin in rabbits. The long sheet membrane of the injected thromboplastin was frequently seen as adhered to the vascular endothelium or to the surface of blood corpuscles. Furthermore, fibrin fibres were formed in contact with the long sheet membrane of the thromboplastin. Membrane structures were not found anywhere in the control rabbits.

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On the Preparation of Bovine α-Thrombin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646669 ◽

1978 ◽

Vol 39 (01) ◽

pp. 193-200 ◽

Cited By ~ 7

Author(s):

Erwin F Workman ◽

Roger L Lundblad

Keyword(s):

Immobilized Enzyme ◽

Catalytic Properties ◽

Specific Activity ◽

Guanidine Hydrochloride ◽

Low Molecular Weight ◽

Reversible Process ◽

Gel Beads ◽

Tissue Thromboplastin ◽

C 50 ◽

Hydrolysis Of

SummaryAn improved method for the preparation of bovine α-thrombin is described. The procedure involves the activation of partially purified prothrombin with tissue thromboplastin followed by chromatography on Sulfopropyl-Sephadex C-50. The purified enzyme is homogeneous on polyacrylamide discontinuous gel electrophoresis and has a specific activity toward fibrinogen of 2,200–2,700 N.I.H. U/mg. Its stability on storage in liquid media is dependent on both ionic strenght and temperature. Increasing ionic strength and decreasing temperature result in optimal stability. The denaturation of α-thrombin by guanidine hydrochloride was found to be a partially reversible process with the renatured species possessing properties similar to “aged” thrombin. In addition, the catalytic properties of a-thrombin covalently attached to agarose gel beads were also examined. The activity of the immobilized enzyme toward fibrinogen was affected to a much greater extent than was the hydrolysis of low molecular weight, synthetic substrates.

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Scientific and Standardization Committee Communications Comparison of Test Methods for the Lupus Anticoagulant: International Survey on Lupus Anticoagulants-I (ISLA-1)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647340 ◽

1990 ◽

Vol 64 (03) ◽

pp. 478-484 ◽

Cited By ~ 28

Author(s):

Thomas Exner ◽

Douglas A Triplett ◽

David A Taberner ◽

Margaret A Howard ◽

E Nigel Harris

Keyword(s):

Lupus Anticoagulant ◽

Test Methods ◽

Positive Sample ◽

Direct Proportion ◽

Clotting Time ◽

Preliminary Screening ◽

Activated Platelets ◽

Tissue Thromboplastin ◽

Kaolin Clotting Time ◽

Induced Defects

SummarySix lyophilized plasma samples were sent to 20 “expert” laboratories for assessment of lupus anticoagulant (LA). Four samples contained pooled LA of graded potency mixed with aged normal plasma. One contained LA plus cephalin phospholipid and one contained a nonspecific venom anticoagulant. Sixteen methods were used overall with some participants using up to 8 methods. Results were scored in regard to the known potencies of LA in the samples and other known induced defects.Activated partial thromboplastin time (APTT) tests used by most participants for preliminary screening were relatively sensitive, but non-specific. Platelet or phospholipid neutralization procedures (PNP) appeared to be sensitive and specific but showed a non-linear response to increased LA content. Kaolin clotting time (KCT) tests showed the most sensitive response to increased LA content but the weaker LA were not scored as abnormal by most laboratories as the samples may have contained platelet fragments. Other commonly used tests such as the tissue thromboplastin inhibition (TTI) test and the dilute Russell’s viper venom test (DRVVT) were carried out somewhat inconsistently. The variability in performance of tests in different laboratories indicates that standardization of methodology is urgently required.Generally it seemed that most clotting tests were “bypassed” by the addition of phospholipid to a known LA-positive sample in apparently direct proportion to their sensitivity. Sample preparation, especially prevention of contamination with activated platelets is a vital preliminary part in the assay of LA.

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Potato Inhibitors of Intrinsic Prothrombin Activators

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651469 ◽

1975 ◽

Vol 34 (03) ◽

pp. 763-769

Author(s):

K Worowski

Keyword(s):

Protease Inhibitors ◽

No Inhibition ◽

Thrombin Activity ◽

Tissue Thromboplastin

SummaryThe potato protease inhibitors inhibit intrinsic prothrombin activators and trypsin activation of prothrombin. The inhibitors 5a and 5b are responsible for the intrinsic prothrombin activator inhibition. This inhibition is progressive. No inhibition by these inhibitors of tissue thromboplastin activation of prothrombin or thrombin activity was observed.

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Factor V from Human Plasma

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654899 ◽

1961 ◽

Vol 05 (01) ◽

pp. 001-020

Author(s):

Douglas M. Surgenor ◽

Nancy A. Wilson ◽

Anne S. Henry

Keyword(s):

Human Serum ◽

Human Plasma ◽

Kinetic Data ◽

Human Factor ◽

Kinetic Studies ◽

Partial Purification ◽

Factor V ◽

Two Stage ◽

Plasma Factor ◽

Tissue Thromboplastin

SummaryA method is described for the partial purification of a human plasma factor which accelerates the conversion of prothrombin to thrombin in the presence of tissue thromboplastin. This factor may be dried from the frozen state, and may be kept in stable dry form for long periods of time. The quantitative assay of this activity is done in a classical two-stage prothrombin system using tissue thromboplastin and calcium. From its properties, it is concluded that this activity corresponds to factor V, labile factor and plasma Ac-globulin.Chemical and kinetic studies reveal that human factor V is active in plasma and is destroyed by thrombin. Human serum has little or no factor V activity.These results thus fail to support the postulated activation of factor V during clotting. All of the kinetic data are consistent with an enzymatic role for factor V in the formation of tissue prothrombin activator (thromboplastin).

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Increased Tissue Thromboplastin Activity in Monocytes of Patients with Meningococcal Infection: Related to an Unfavourable Prognosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657303 ◽

1983 ◽

Vol 49 (01) ◽

pp. 005-007 ◽

Cited By ~ 203

Author(s):

B Østerud ◽

T Flægstad

Keyword(s):

Disseminated Intravascular Coagulation ◽

Fold Increase ◽

Meningococcal Infection ◽

High Concentration ◽

Intravascular Coagulation ◽

Tissue Thromboplastin ◽

Unfavourable Prognosis

SummaryIn 16 patients, 13 with meningococcal infection and 3 suspected to have this infection, 8 patients were found to possess significant higher level of tissue thromboplastin activity of their monocytes isolated from the blood at the admission to the hospital than normal. Five of those 8 patients had an extremely high concentration, > 60-300 fold increase, and all these patients died. The exposed tissue thromboplastin activity on the surface of the endotoxin stimulated monocytes is probably the direct inducer of disseminated intravascular coagulation (DIC) in meningococcal infection.

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Questions and Answers on Prothrombin Time Standardisation in Oral Anticoagulant Control

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657886 ◽

1985 ◽

Vol 54 (02) ◽

pp. 515-517 ◽

Cited By ~ 55

Author(s):

E A Loeliger ◽

L Poller ◽

M Samama ◽

J M Thomson ◽

A M H P Van den Besselaar ◽

...

Keyword(s):

Plasma Sample ◽

Oral Anticoagulants ◽

Sensitivity Index ◽

International Normalised Ratio ◽

Questions And Answers ◽

Reference Preparation ◽

Tissue Thromboplastin ◽

The Individual ◽

International Sensitivity Index ◽

New System

SummaryOne of the reasons why oral anticoagulants fell into disrepute is the absence of internationally accepted standardised procedures for controlling the level of anticoagulatiori. This deplorable situation resulted in over- and under-coagulation and uncertainty in the therapeutic range. International conformity can now be obtained by using an International Normalised Ratio (INR) which is derived from the individual result obtained in a given plasma sample and the International Sensitivity Index (ISI) of the tissue thromboplastin reagent used. Any thromboplastin reagent can be calibrated against an international primary or secondary W.H.O. reference preparation, so as to obtain its International Sensitivity Index. The new system of reporting the level of anticoagulation was designed and can only safely be applied in patients taking oral anticoagulants.

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Ultramicroscopic and Coagulation-Fibrinolytic Findings Induced by Tissue Thromboplastin

10.1055/s-0038-1665796 ◽

1979 ◽

Author(s):

H Nagata ◽

T Seya ◽

Y Oguma ◽

M Yamauchi ◽

T Murakoshi ◽

...

Keyword(s):

Endothelial Cells ◽

Electron Microscope ◽

Transmission Electron Microscope ◽

Hypercoagulable State ◽

Membrane Structures ◽

Transmission Electron ◽

Single Sheet ◽

Tissue Thromboplastin ◽

Short Time

We have studied the ultrastructures of tissue thromboplastin (T.Tbp) to demonstrate how It changes during coagulation.[Materials and Methods] T.Tbp from lungs of rabbits was used for these studies. It was injected into ear veins of rabbits. Lungs were resected at several seconds, 10sec, 1 min, 5 min, 24 hrs or 48 hrs after the injection. They were examined by transmission electron microscope.[Results] Concentrically arranged membrane structures of the injected T.Tbp disappeared in extremely short time after the injection. 1 min after the injection, fibrin fibers were seen between single sheet of membrane and endothelial cells of capillaries. In the rabbit which had died suddenly after the injection of T.Tbp, multiple pulmonary thrombi made of fibrin and platelets were seen in capillaries. The endothelial cells of capillaries were destroyed and interstitial tissues were edematous.The hypercoagulable state was seen 10~30sec after the start of the injection, indicating the shortening of r of TEG. Then, it gradually returned the level before injection. Moreover, changes of the measurements of fibrinogen, antiplasmin and prekallikrein were also seen after the injection.

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