Influence of Organ Extracts on Blood Clotting Factors

1959 ◽  
Vol 03 (04) ◽  
pp. 491-500 ◽  
Author(s):  
P Fantl ◽  
H. A Ward
Keyword(s):  
Blood Clotting ◽  
Factor Ix ◽  
Factor Vii ◽  
Clotting Factors ◽  
Heat Stable ◽  
Ether Extraction ◽  
The Brain ◽  
Blood Clotting Factors

SummaryBrain and lung suspensions incubated with blood or serum produce sera which are deficient in factor IX and factor VII.Suspensions prepared from acetone-dehydrated brain are effective substitutes for free phospholipids in the formation of blood thromboplastin.The fraction which inactivates the clotting factors is connected with a readily sedimentable portion of the brain suspension.It is heat stable, and destroyed by ethanol-ether extraction.The extracted lipid is inactive.

Snake Venom Phospholipases A2And Blood Coagulation : Competition Between Phospholipases And Blood Clotting Factors U And U At The Phospholipid Interface

1981 ◽  
Author(s):  
J Prigentdachary ◽  
M R Boisseau ◽  
J Dufourcq
Keyword(s):  
Blood Clotting ◽  
Anticoagulant Activity ◽  
Plasma Phospholipid ◽  
Factor Ix ◽  
Molar Ratio ◽  
Binding Affinities ◽  
Coagulation Test ◽  
Clotting Factors ◽  
Phospholipases A2 ◽  
Blood Clotting Factors

In a preceeding paper (J. Biol. Chem., 255, 7734-7739, 1980) we have shown that phospholipases A2 from snake venoms have different phospholipid binding affinities according, to their anticoagulant activities : only the anticoagulant one are able to bind with neutral and negative phospholipid bilayers in EDTA and therefore in coagulation test could hydrolyse both classes of lipids. A step forward in the understanding of the mechanism of the inhibitory action of phospholipases on coagulation is to know if competition between clotting factors and phospholipase can occur at the plasma phospholipid interface as a consequence of the strong affinity of anticoagulant phospholipase for lipids. The method used is mainly to look at the intrinsic fluorescence of lipids bound phospholipase when blood clotting factors II and IX are added to the complex. Results show that both factors can expel the phospholipase from the interface when the factor to phospholipase molar ratio is about 1, suggesting a better affinity of the clotting proteins for the interface. When hydrolysis of phospholipids is allowed to occur (ie in presence of calcium ion) factors also have a good affinity for degraded products. By the same technic, it was also possible to dectect direct interactions between phospholipase and factors, which differ for factors II and factor IX. This can also occur in presence of phospholipids. In summary, as it was demonstrated that inactivated phospholipase has lost its anticoagulant activity lipid hydrolysis is a necessary step. However, we show here that competition between clotting factors and phospholipase could also occur if drastic concentrations of phospholipase are used in coagulation test, i.e. molar ratio much higher than 1. It is also proposed that factor to phospholipase binding may be important in the inhibitory mechanism since clotting proteins could be no longer available for the coagulation.

Blood Coagulation Studies and Extracorporeal Circulation in Man

1967 ◽  
Vol 18 (03/04) ◽  
pp. 634-646 ◽  
Author(s):  
N Thurnherr
Keyword(s):  
Blood Coagulation ◽  
Extracorporeal Circulation ◽  
Blood Clotting ◽  
Heart Surgery ◽  
Open Heart Surgery ◽  
Fibrinolytic System ◽  
Open Heart ◽  
Clotting Factors ◽  
Blood Clotting Factors

SummaryBlood clotting investigations have been executed in 25 patients who have undergone open heart surgery with extracorporeal circulation. A description of alterations in the activity of blood clotting factors, the fibrinolytic system, prothrombin consumption and platelets during several phases of the operation is given.

scholarly journals Coagulation Disturbances in Patients with Argininemia

2018 ◽  
Vol 140 (4) ◽  
pp. 221-225 ◽  
Author(s):  
Ertugrul Kiykim ◽  
Tanyel Zubarioglu ◽  
Mehmet Serif Cansever ◽  
Tiraje Celkan ◽  
Johannes Häberle ◽  
...  
Keyword(s):  
Autosomal Recessive ◽  
Urea Cycle ◽  
International Normalized Ratio ◽  
Factor Ix ◽  
Factor Vii ◽  
Clotting Factor ◽  
Clotting Factors ◽  
Hepatic Involvement ◽  
Prolonged Aptt ◽  
Liver Transaminases

Background: Argininemia is an autosomal recessive urea cycle disorder (UCD). Unlike other UCD, hyperammonemia is rarely seen. Patients usually present in childhood with neurological symptoms. Uncommon presentations like neonatal cholestasis or cirrhosis have been reported. Although transient elevations of liver transaminases and coagulopathy have been reported during hyperammonemia episodes, a permanent coagulopathy has never been reported. Methods: In this retrospective study, coagulation disturbances are examined in 6 argininemia patients. All of the patients were routinely followed up for hepatic involvement due to argininemia. Laboratory results, including liver transaminases, albumin, prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), and clotting factor levels, were assessed in all of the patients. Results: All of the patients had a prolonged PT and an increased INR, while none of the patients had a prolonged aPTT. Five patients had slightly elevated liver transaminases. A liver biopsy was performed in 1 patient but neither cirrhosis nor cholestasis was documented. Five of the 6 patients had low factor VII and factor IX levels, while other clotting factors were normal. Conclusions: Argininemia patients should be investigated for coagulation disorders even if there is no apparent liver dysfunction or major bleeding symptoms.

Topology of the binding site of blood-clotting factors in model membranes. A fluorescence study

1986 ◽  
Vol 155 (1) ◽  
pp. 133-140 ◽  
Author(s):  
Jeanne PRIGENT-DACHARY ◽  
Jean-Francois FAUCON ◽  
Michel-Rene BOISSEAU ◽  
Jean DUFOURCQ
Keyword(s):  
Binding Site ◽  
Blood Clotting ◽  
Model Membranes ◽  
Clotting Factors ◽  
Fluorescence Study ◽  
Blood Clotting Factors

EXPRESSION IN MAMMALIAN CELLS OF FUSION PROTEINS BETWEEN HUMAN FACTORS IX AND VII

1987 ◽  
Author(s):  
K L Berkner ◽  
S J Busby ◽  
J Gambee ◽  
A Kumar
Keyword(s):  
Fusion Protein ◽  
Fusion Proteins ◽  
Factor Ix ◽  
Biologically Active ◽  
Factor Vii ◽  
Clotting Factor ◽  
Clotting Factors ◽  
Mammalian Expression ◽  
Plasma Factor ◽  
Gla Domain

The vitamin K-dependent plasma proteins demonstrate remarkable similarities in their structures: all have multiple domains in common and extensive homology is observed within many of these domains. In order to investigate the structure-function relationship of these proteins, we have interchanged domains of one protein (factor IX) with that of another (factor VII) and have compared the expression of these fusion proteins with recombinant and native factors IX and VII. Oligonucleotide-directed mutagenesis was used to generate four fusion proteins: factor IX/VII-1, which contains the factor IX leader and gla domain fused to the growth factor and serine protease of factor VII; factor VII/IX-1, a reciprocal fusion protein of factor IX/VII-1; factor IX/VII-2, which contains the factor IX leader adjoined to the mature factor VII protein sequence; and factor VII/IX-2, the reciprocal fusion protein of factor IX/VII-2. The cDNAs encoding all four proteins were cloned into mammalian expression vectors, and to date three of these (factors IX/VII-1, 2 and VII/IX-1) have been transfected into baby hamster kidney (BHK) cells or 293 cells and characterized. Factors IX/VII-1 and VII/IX-1 were both secreted at levels comparable to recombinant factors IX and VII. The factor IX/VII-1 was identical in molecular weight to native or recombinant factor VII (i.e., 53 K). Factor VII/IX-1 was expressed as two proteins with molecular weights around 68 kd, as observed with recombinant factor IX. The factor IX/VII-1 protein has been purified to homogeneity and has been found to possess factor VII biological activity, but at a specific activity approximately 20% that of plasma factor VII. Thus, the gla domain of one clotting factor is capable of directing the activation of another and of generating biologically active protein. In contrast, no activity was observed with the factor IX/VII-2 fusion protein, indicating that there are limits to the interchanges which can generate functional blood clotting factors.

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