EFFECTS OF INTRAVENOUS INJECTIONS OF THE ANTICOAGULANT FRACTION OF INCUBATED FIBRINOGEN ON BLOOD COAGULATION

1960 ◽  
Vol 38 (8) ◽  
pp. 909-918 ◽  
Author(s):  
D. C. Triantaphyllopoulos
Keyword(s):  
Prothrombin Time ◽  
Bleeding Time ◽  
Jugular Vein ◽  
Coagulation Factors ◽  
External Jugular Vein ◽  
Anticoagulant Effect ◽  
Clotting Time ◽  
Intravenous Injections ◽  
Fibrinogen Content ◽  
Ammonium Sulphate Saturation

AFIF (Anticoagulant Fraction of Incubated Fibrinogen precipitated between 25 and 50% ammonium sulphate saturation) prepared from Armour's incubated bovine fibrinogen was injected in a dosage of 46–106 mg (mean: 66.5 mg) tyrosine per kilogram body weight in the external jugular vein of 10 rabbits. Blood samples were withdrawn at [Formula: see text]- or 1-hour intervals until the aspirated blood began showing signs of coagulation. The anticoagulant effect was manifested immediately and lasted for [Formula: see text] to [Formula: see text] hours in the animal. Although the blood aspirated during this time remained unclotted even after 24 hours, the surgical wound in the neck of the animal did not bleed and autopsies revealed no sign of internal haemorrhage. The bleeding time, however, was found prolonged when tested by cutting the marginal vein of the ear. The level of the coagulation factors was determined both in oxalated specimens and in specimens with no anticoagulant added. Both kinds of sample showed: (1) clottable fibrinogen content normal, thus excluding fibrinolysis as the cause of the anticoagulant effect; (2) thrombin clotting time of infinity; (3) one-stage prothrombin time longer than 60 seconds; (4) no correction of the infinite thrombin clotting time of oxalated specimens following the addition of 0.25 mg protamine per ml. This makes unlikely any appreciable release of heparin by the animal. However, oxalated and non-oxalated specimens differed in the following respects: (1) prothrombin time determined after adsorption and mixing of the eluate with adsorbed plasma was found to be normal for the oxalated blood but variably increased for the non-oxalated specimen (10–34.5 seconds); (2) the plasma precursors of plasma thromboplastin were normal in oxalated but very low in native specimens. The serum precursors of plasma thromboplastin were normal.

EFFECTS OF INTRAVENOUS INJECTIONS OF THE ANTICOAGULANT FRACTION OF INCUBATED FIBRINOGEN ON BLOOD COAGULATION

1960 ◽  
Vol 38 (1) ◽  
pp. 909-918 ◽  
Author(s):  
D. C. Triantaphyllopoulos
Keyword(s):  
Prothrombin Time ◽  
Bleeding Time ◽  
Jugular Vein ◽  
Coagulation Factors ◽  
External Jugular Vein ◽  
Anticoagulant Effect ◽  
Clotting Time ◽  
Intravenous Injections ◽  
Fibrinogen Content ◽  
Ammonium Sulphate Saturation

AFIF (Anticoagulant Fraction of Incubated Fibrinogen precipitated between 25 and 50% ammonium sulphate saturation) prepared from Armour's incubated bovine fibrinogen was injected in a dosage of 46–106 mg (mean: 66.5 mg) tyrosine per kilogram body weight in the external jugular vein of 10 rabbits. Blood samples were withdrawn at [Formula: see text]- or 1-hour intervals until the aspirated blood began showing signs of coagulation. The anticoagulant effect was manifested immediately and lasted for [Formula: see text] to [Formula: see text] hours in the animal. Although the blood aspirated during this time remained unclotted even after 24 hours, the surgical wound in the neck of the animal did not bleed and autopsies revealed no sign of internal haemorrhage. The bleeding time, however, was found prolonged when tested by cutting the marginal vein of the ear. The level of the coagulation factors was determined both in oxalated specimens and in specimens with no anticoagulant added. Both kinds of sample showed: (1) clottable fibrinogen content normal, thus excluding fibrinolysis as the cause of the anticoagulant effect; (2) thrombin clotting time of infinity; (3) one-stage prothrombin time longer than 60 seconds; (4) no correction of the infinite thrombin clotting time of oxalated specimens following the addition of 0.25 mg protamine per ml. This makes unlikely any appreciable release of heparin by the animal. However, oxalated and non-oxalated specimens differed in the following respects: (1) prothrombin time determined after adsorption and mixing of the eluate with adsorbed plasma was found to be normal for the oxalated blood but variably increased for the non-oxalated specimen (10–34.5 seconds); (2) the plasma precursors of plasma thromboplastin were normal in oxalated but very low in native specimens. The serum precursors of plasma thromboplastin were normal.

scholarly journals Antithrombotic activity of Mentha longifolia in animal model

2018 ◽  
Vol 13 (1) ◽  
pp. 67
Author(s):  
. Alamgeer ◽  
Qurat ul Ain ◽  
Umme Habiba Hasan ◽  
Hira Asif
Keyword(s):  
Prothrombin Time ◽  
Bleeding Time ◽  
Research Work ◽  
Vascular Diseases ◽  
Maximum Effect ◽  
Clotting Time ◽  
Antithrombotic Activity ◽  
Mentha Longifolia

<p class="Abstract">The present research work was conducted to appraise the antithrombotic activity of Mentha longifolia using in vitro and in vivo experiments. Aqueous methanolic (70:30) extract produced significant (p&lt;0.01-0.001) and dose-dependent increase in in vitro blood clotting time, bleeding time, prothrombin time and activated partial thromboplastin level with maximum effect at highest concentration. While in in vivo experiment, aqueous methanol extract showed noteworthy (p&lt;0.01-0.001) prolongation in bleeding time and clotting time after 30, 60 and 90 min of administration except for 25 mg/kg at 30 min which is non-significant. Moreover, plant extract exhibited considerable increase (p&lt;0.1-0.001) in bleeding time, clotting time, prothrombin time as well as activated partial thromboplastin time in rabbits after seven days of treatment. Additionally, HPLC analysis of M. longifolia aqueous methanolic extract illustrated the presence of various valuable phytoconstituents. In a nutshell, M. longifolia possesses potential antithrombotic activity and hence systematically proved to be beneficial in patients with vascular diseases.</p>

ANTICOAGULANT EFFECT OF INCUBATED FIBRINOGEN

1958 ◽  
Vol 36 (1) ◽  
pp. 249-259 ◽  
Author(s):  
D. C. Triantaphyllopoulos
Keyword(s):  
Ammonium Sulphate ◽  
Coagulation Factors ◽  
The Other ◽  
Anticoagulant Effect ◽  
Factor Vii ◽  
Factor V ◽  
Thrombin Time ◽  
Fresh Plasma ◽  
Native Plasma ◽  
Ammonium Sulphate Saturation

Sterile fibrinogen rendered non-clottable by incubation was mixed with fresh plasma and the thrombin time determined. An appreciable prolongation was observed. The incubated fibrinogen was then fractionally precipitated with ammonium sulphate. The material precipitated between 25 and 50% ammonium sulphate saturation, when added to freshly drawn but still unclotted blood, or native plasma, prevented its coagulation. This action could be reversed by an approximately fivefold dilution with distilled water and addition of calcium chloride and thrombin, thus excluding fibrinolysis as the cause of the anticoagulant effect. Determinations of the respective coagulation factors showed that no decrease occurred in prothrombin, factor VII, plasma thromboplastin component, and fibrinogen. On the other hand a statistically significant decrease in factor V was observed when calcium was present.

Fibrinogen assays: a collaborative study of six different methods. C.I.S.M.E.L. Comitato Italiano per la Standardizzazione dei Metodi in Ematologia e Laboratorio

1991 ◽  
Vol 37 (5) ◽  
pp. 714-719 ◽  
Author(s):  
G Palareti ◽  
M Maccaferri ◽  
C Manotti ◽  
A Tripodi ◽  
V Chantarangkul ◽  
...  
Keyword(s):  
Prothrombin Time ◽  
Collaborative Study ◽  
Internal Standard ◽  
Calibration Procedure ◽  
Radial Immunodiffusion ◽  
Clotting Time ◽  
International Standard ◽  
Fibrinogen Content

Abstract This collaborative study, organized by the Hemostasis Subcommittee of C.I.S.M.E.L., evaluated the accuracy, precision, and comparability of the following six widely used fibrinogen assays: total clottable fibrinogen (Blombäck and Blombäck), clotting time (Von Clauss), turbidimetry (Ellis and Stransky), Chromotime System, prothrombin time (PT)-derived, and radial immunodiffusion (RID). The same frozen samples, with normal and high contents of fibrinogen, were examined in four laboratories. The methods were calibrated with an internal standard whose fibrinogen content was determined gravimetrically. Both the Von Clauss and the RID methods were reliable, accurate, and precise, if adequate calibration was used. The PT-derived method was highly reproducible, but had some problems with accuracy. We demonstrate that an adequate calibration procedure is indispensable for reliable fibrinogen measurements whatever method is used. Because neither the calibration procedures proposed by the manufacturers nor the use of lyophilized commercial plasmas is adequate for this purpose, we urge that an international standard for fibrinogen measurement be promptly established.

scholarly journals The Hemostatic Defect of Uremia

Blood ◽  
1956 ◽  
Vol 11 (12) ◽  
pp. 1059-1066 ◽  
Author(s):  
CAMILO LARRAIN ◽  
EDWARD ADELSON
Keyword(s):  
Renal Insufficiency ◽  
Bleeding Time ◽  
Anticoagulant Effect ◽  
Clotting Time ◽  
Prolonged Bleeding ◽  
Prolonged Bleeding Time ◽  
Acute Renal Insufficiency ◽  
Plasma Factors

Abstract The abnormalities of the hemostatic mechanism in three consecutive patients with acute renal insufficiency have been studied. In every case a prolonged clotting time in silicone and a prolonged bleeding time were found. In two cases defective prothrombin consumption was also present. Coagulation studies revealed no significant deficiency of plasma factors, no serious deficiency of platelet numbers or function and no well-defined anticoagulant effect to explain the changes. All three cases developed significant clinical bleeding at some time during the course of the renal insufficiency.

ANTICOAGULANT EFFECT OF INCUBATED FIBRINOGEN

1958 ◽  
Vol 36 (3) ◽  
pp. 249-259 ◽  
Author(s):  
D. C. Triantaphyllopoulos
Keyword(s):  
Ammonium Sulphate ◽  
Coagulation Factors ◽  
The Other ◽  
Anticoagulant Effect ◽  
Factor Vii ◽  
Factor V ◽  
Thrombin Time ◽  
Fresh Plasma ◽  
Native Plasma ◽  
Ammonium Sulphate Saturation

Sterile fibrinogen rendered non-clottable by incubation was mixed with fresh plasma and the thrombin time determined. An appreciable prolongation was observed. The incubated fibrinogen was then fractionally precipitated with ammonium sulphate. The material precipitated between 25 and 50% ammonium sulphate saturation, when added to freshly drawn but still unclotted blood, or native plasma, prevented its coagulation. This action could be reversed by an approximately fivefold dilution with distilled water and addition of calcium chloride and thrombin, thus excluding fibrinolysis as the cause of the anticoagulant effect. Determinations of the respective coagulation factors showed that no decrease occurred in prothrombin, factor VII, plasma thromboplastin component, and fibrinogen. On the other hand a statistically significant decrease in factor V was observed when calcium was present.

scholarly journals The Exposure of Phosphatidylserine Influences Procoagulant Activity in Retinal Vein Occlusion by Microparticles, Blood Cells, and Endothelium

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Ying Su ◽  
Xueqing Deng ◽  
Ruishuang Ma ◽  
Zengxiang Dong ◽  
Feng Wang ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Endothelial Cells ◽  
Retinal Vein Occlusion ◽  
Blood Cells ◽  
Coagulation Factors ◽  
Procoagulant Activity ◽  
Anticoagulant Effect ◽  
Clotting Time ◽  
Coagulation Time ◽  
Vein Occlusion

The pathogenesis of hypercoagulability in retinal vein occlusion (RVO) is largely unknown. Whether the exposure of phosphatidylserine (PS) and microparticle (MPs) release will affect procoagulant activity (PCA) in RVO needs to be investigated.Objectives. To evaluate PS expression, circulating MPs, and the corresponding PCA in RVO patients. Twenty-five RVO patients were compared with 25 controls. PS-positive cells were detected by flow cytometry. Cell-specific MPs were measured by lactadherin for PS and relevant CD antibody. We explored PCA with coagulation time, purified coagulation complex assays, and fibrin production assays. In RVO, MPs from platelets, erythrocytes, leukocyte, and endothelial cells were increased and the exposure of PS was elevated significantly when compared with controls. In addition, we showed that circulating MPs in RVO patients were mostly derived from platelets, representing about 60–70% of all MPs, followed by erythrocytes and leukocytes. Moreover, PS exposure, ECs, and MPs in RVO lead to shortened clotting time with upregulation of FXa and thrombin formation obviously. Importantly, ECs treated with RVO serum which bounded FVa and FXa explicitly suggested the damage of retinal vein endothelial cells. Furthermore, lactadherin can inhibit the combination between PS and coagulation factors by approximately 70% and then exert an anticoagulant effect. In summary, circulating MPs and exposed PS from different cells may contribute to the increased PCA in patients with RVO. Lactadherin can be used for PS detection and an anticoagulant agent.

Efficacy of prothrombin complex concentrate to reverse the anticoagulant effect of the pentasaccharide fondaparinux in a rabbit model

2011 ◽  
Vol 105 (01) ◽  
pp. 161-168 ◽  
Author(s):  
Marion Durand ◽  
Joseph Emmerich ◽  
Blandine Dizier ◽  
Thomas Lecompte ◽  
Charles-Marc Samama ◽  
...  
Keyword(s):  
Blood Flow ◽  
Blood Loss ◽  
Prothrombin Complex Concentrate ◽  
Bleeding Time ◽  
Rabbit Model ◽  
Anticoagulant Effect ◽  
Efficacy And Safety ◽  
Clotting Time ◽  
Local Blood Flow ◽  
Cyclic Flow

SummaryAs a potent anticoagulant agent, fondaparinux exposes a risk of bleeding. An effective way to reverse its effects is needed. It was the objective to study efficacy and safety of prothrombin complex concentrate (PCC) to reverse the anticoagulant effect of fondaparinux in a rabbit model of bleeding and thrombosis. In anaesthetised and ventilated rabbits, the Folts model was applied: a stenosis (75%) and an injury were carried out on the carotid artery, inducing thrombosis. Blood flow decreased as thrombus size increased until the pressure gradient was such that the thrombus was released and local blood flow was suddenly restored. This is known as a cyclic flow reduction (CFR). After the first CFR, rabbits were randomised into three groups: control (saline and saline after 1 minute), fondaparinux (fondaparinux [3 mg.kg−1] and saline), PCC (fondaparinux and PCC [40 UI.kg−1]). Then CFRs were recorded over 20 minutes. The following were measured: ear immersion bleeding time (BT), haemoglobin blood level (Hb1) and thrombelasto-metric parameters (ROTEM®). Finally, a hepatosplenic section was performed; 15 minutes later, the amount of blood loss was recorded as primary endpoint and Hb2 was measured. Blood loss was increased with fondaparinux and normalised with PCC. Regarding ROTEM® INTEM, fondaparinux increased clotting time and clotting formation time. PCC normalised these parameters. EXTEM and FIBTEM tests were not modified. Regarding safety, PCC did not increase CFRs. PCC reduced bleeding without increasing thrombosis and was effective to reverse the haemorrhagic effect of fondaparinux in this rabbit model.

Essential Athrombia

1975 ◽  
Vol 33 (02) ◽  
pp. 278-285 ◽  
Author(s):  
Şeref Inceman ◽  
Yücel Tangün
Keyword(s):  
Platelet Aggregation ◽  
Bleeding Time ◽  
Bleeding Tendency ◽  
Clot Retraction ◽  
Platelet Factor ◽  
Prolonged Bleeding Time ◽  
Normal Platelet ◽  
Aggregation Response ◽  
Platelet Disorder ◽  
Fibrinogen Content

SummaryA constitutional platelet function disorder in a twelve-year-old girl characterized by a lifelong bleeding tendency, prolonged bleeding time, normal platelet count, normal clot retraction, normal platelet factor 3 activity and impaired platelet aggregation was reported.Platelet aggregation, studied turbidimetrically, was absent in the presence of usual doses of ADP (1–4 μM), although a small wave of primary aggregation was obtained by very large ADP concentrations (25–50 μM). The platelets were also unresponsive to epinephrine, thrombin and diluted collagen suspensions. But an almost normal aggregation response occurred with strong collagen suspensions. The platelets responded to Ristocetin. Pelease of platelet ADP was found to be normal by collagen and thrombin, but impaired by kaolin. Platelet fibrinogen content was normal.The present case, investigated with recent methods, confirms the existence of a type of primary functional platelet disorder characterized solely by an aggregation defect, described in 1955 and 1962 under the name of “essential athrombia.”

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