scholarly journals Heparinized Polyurethane Surface Via a One-Step Photografting Method

Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 758 ◽  
Author(s):  
Zhangshuan Liu ◽  
Liming Fang ◽  
Guillaume Delaittre ◽  
Yu Ke ◽  
Gang Wu
Keyword(s):  
Platelet Adhesion ◽  
Antithrombin Iii ◽  
Thrombin Time ◽  
Binding Ability ◽  
Aryl Azide ◽  
One Step ◽  
Heparin Derivatives ◽  
Low Efficiency ◽  
Plasma Recalcification Time ◽  
Recalcification Time

Traditional methods using coupling chemistry for surface grafting of heparin onto polyurethane (PU) are disadvantageous due to their generally low efficiency. In order to overcome this problem, a quick one-step photografting method is proposed here. Three heparin derivatives incorporating 0.21, 0.58, and 0.88 wt% pendant aryl azide groups were immobilized onto PU surfaces, leading to similar grafting densities of 1.07, 1.17, and 1.13 μg/cm2, respectively, yet with increasing densities of anchoring points. The most negatively charged surface and the maximum binding ability towards antithrombin III were found for the heparinized PU with the lowest amount of aryl azide/anchor sites. Furthermore, decreasing the density of anchoring points was found to inhibit platelet adhesion to a larger extent and to prolong plasma recalcification time, prothrombin time, thrombin time, and activated partial thromboplastin time to a larger extent. This was also found to enhance the bioactivity of immobilized heparin from 22.9% for raw heparin to 36.9%. This could be explained by the enhanced molecular mobility of immobilized heparin when it is more loosely anchored to the PU surface, as well as a higher surface charge.

scholarly journals Preparation of modified polysulfone material decorated by sulfonated citric chitosan for haemodialysis and its haemocompatibility

2021 ◽  
Vol 8 (9) ◽  
pp. 210462
Author(s):  
Bingxian Lin ◽  
Kaiming Liu ◽  
Yunren Qiu
Keyword(s):  
Contact Angle ◽  
Active Sites ◽  
Platelet Adhesion ◽  
Activated Partial Thromboplastin Time ◽  
Thrombin Time ◽  
Chloroacetyl Chloride ◽  
Water Contact ◽  
H Nmr ◽  
Plasma Recalcification Time ◽  
Recalcification Time

Polysulfone (PSF) works potentially in haemodialysis due to its great mechanical and chemical stability, but performs poorly in haemocompatibility. For promoting the unpleasant haemocompatibility, sulfonated citric chitosan (SCACS) with the structure and groups similar to heparin was primarily synthesized by acylation and sulfonation. Furthermore, the chloroacylated PSF was pretreated by electrophilic chloroacetyl chloride to achieve more active sites for further reaction; the following membranes underwent the amination and were named amination polysulfone (AMPSF) membranes. Moreover, SCACS with abundant carboxyl and sulfonic groups was covalently grafted at the surface of pretreated PSF membranes, called PSF-SCACS membranes. The PSF-SCACS membranes were successfully synthesized and characterized by 1 H NMR, ATR-FTIR and XPS. In addition, the water contact angle of PSF-SCACS membranes decreased by 47° and the morphologies of the membranes changed little compared with the unmodified PSF membranes. The haemocompatible testing results, including protein adsorption, platelet adhesion, haemolysis rate, plasma recalcification time, activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT), demonstrated that the PSF-SCACS membranes possessed excellent haemocompatible performances, and SCACS played an important role in the modification.

Blood Coagulation and Fibrinolysis in Haemorrhagic Stroke

1978 ◽  
Vol 39 (01) ◽  
pp. 084-088 ◽  
Author(s):  
Rama Kanta Dube ◽  
P V B Rao ◽  
P K Saha ◽  
B C Katiyar ◽  
B Dube
Keyword(s):  
Platelet Count ◽  
Prothrombin Time ◽  
Fibrinolytic Activity ◽  
Haemorrhagic Stroke ◽  
Factor V ◽  
Thrombin Time ◽  
Clotting Time ◽  
Plasma Recalcification Time ◽  
Recalcification Time ◽  
Coagulation And Fibrinolysis

SummaryStudies of 11 patients with haemorrhagic stroke revealed no significant change in kaolin cephalin clotting time, prothrombin time, thrombin time, PF 3 availability, platelet count and factor V and VIII during the first week. Plasma fibrinogen was significantly increased while factors VII+X were decreased (borderline significance). Prolongation of plasma recalcification time and decrease in heparin tolerance reached borderline significance. There was moderate, but significant, increase in serum antithrombin activity and plasma (euglobulin fraction) fibrinolytic activity.

The Fate Of Surface Bound Heparin And The Long Term Thromboresistance Of Heparinized Materials

1981 ◽  
Author(s):  
M F A Goosen ◽  
M V Sefton ◽  
M W C Hatton
Keyword(s):  
Antithrombin Iii ◽  
Removal Rate ◽  
Thrombin Time ◽  
Circulatory Assist Devices ◽  
Important Means ◽  
Pva Gel ◽  
Av Shunt ◽  
Thrombin Antithrombin Iii Complex ◽  
Recalcification Time

Displacement by plasma of radiolabeled thrombin and radiolabeled thrombin-antithrombin III inactive complex from a heparinized surface (heparin-PVA) was measured and found to be significant. For example, 63% of the thrombin and 90% of the complex that could not be removed by PBS alone was displaced by heat defibrinated plasma. Preliminary characterization (molecular weight, antithrombin III content) suggests that the eluting product consists largely of thrombin-antithrombin III complex and post complex antithrombin III. Heparin polyvinyl alcohol (PVA) gel beads were prepared by acetal coupling of the heparin to PVA using glutaraldehyde with MgCl2 catalysis. Although permanently bound to the PVA (heparin removal rate was 1.67 × 10-2 mg/g gel⋅min), the heparin retained at least part of its activity in thrombin time, recalcification time, chromogenic substrate and AV shunt assays. Thus, heparin need not be lost from a surface to impart thromboresistance. Our results further suggest that the resulting surface bound thrombin-antithrombin III complex can be displaced from the surface by a component or components of plasma (antithrombin III?) indicating that the surface bound heparin does not become saturated with inactive complex. These results support the argument that heparinization can be an important means of preparing the materials needed for the development of improved cardio-circulatory assist devices and blood handling procedures.

Coagulation Findings in Rats with Experimental Hypersplenism and Their Changes after Splenectomy and after Administration of Adrenaline

1970 ◽  
Vol 23 (03) ◽  
pp. 593-600
Author(s):  
P Pudlák ◽  
I Farská ◽  
V Brabec ◽  
V Pospíšilová
Keyword(s):  
Factor Viii ◽  
Normal Control ◽  
Normal Values ◽  
Coagulation Factors ◽  
Factor Vii ◽  
Factor V ◽  
Thrombin Time ◽  
Factor Ii ◽  
Recalcification Time

Summary1. The following coagulation changes were found in rats with experimental hypersplenism: a mild prolongation of the recalcification time, shortened times in Quick’s test, a lowered activity in plasma thrombin time and shortened times in the partial thromboplastin test. Concentrations of factor II, V, VII (+X), VIII and X did not differ from those of normal control rats.2. The administration of adrenaline to hypersplenic rats induced the correction of the partial thromboplastin test, Quick’s test and plasma thrombin time to normal values. Concentrations of coagulation factors were not significantly changed. An increase was found in factor V.3. Splenectomy performed in hypersplenic rats was followed by a shortened recalcification time, a prolongation of the partial thromboplastin test and of the test with partial thromboplastin and kaolin. A prolongation was also observed in Quick’s test. Complete correction of plasma thrombin time was not observed. The concentration of factor VII increased.4. The administration of adrenaline to splenectomized rats with experimental hypersplenism did not induce any significant changes with the exception of a corrected plasma thrombin time and a decreased concentration of factor VIII.5. A different reaction of factor VIII to adrenaline in normal and hypersplenic rats is pointed out.

Effects of Heparin Oligosaccharides with High Affinity for Antithrombin III in Experimental Venous Thrombosis

1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl
Keyword(s):  
Antithrombin Iii ◽  
Specific Activity ◽  
High Specific Activity ◽  
Factor Xa ◽  
Blood Levels ◽  
Thrombin Time ◽  
High Affinity ◽  
Very High

SummaryThe in vitro and in vivo characteristics of two oligosaccharide heparin fragments have been compared to those of unfractionated mucosal heparin. A decasaccharide fragment had essentially no activity by APTT or calcium thrombin time assays in vitro, but possessed very high specific activity by anti-Factor Xa assays. When injected into rabbits at doses of up to 80 ¼g/kg, this fragment was relatively ineffective in impairing stasis thrombosis despite producing high blood levels by anti-Xa assays. A 16-18 monosaccharide fragment had even higher specific activity (almost 2000 iu/mg) by chromogenic substrate anti-Xa assay, with minimal activity by APTT. When injected in vivo, this fragment gave low blood levels by APTT, very high anti-Xa levels, and was more effective in preventing thrombosis than the decasaccharide fragment. However, in comparison with unfractionated heparin, the 16-18 monosaccharide fragment was only partially effective in preventing thrombosis, despite producing much higher blood levels by anti-Xa assays.It is concluded that the high-affinity binding of a heparin fragment to antithrombin III does not by itself impair venous thrombogenesis, and that the anti-Factor Xa activity of heparin is only a partial expression of its therapeutic potential.

Fifteen Coagulation and Fibrinolysis Parameters in Diabetes Mellitus and in Patients with Vasculopathy

1984 ◽  
Vol 52 (02) ◽  
pp. 138-143 ◽  
Author(s):  
M Christe ◽  
J Fritschi ◽  
B Lämmle ◽  
T H Tran ◽  
G A Marbet ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Peripheral Arterial Disease ◽  
Negative Correlation ◽  
Fibrinolytic Activity ◽  
Antithrombin Iii ◽  
Predictor Variable ◽  
Arterial Disease ◽  
Thrombin Time ◽  
Peripheral Arterial ◽  
Coagulation And Fibrinolysis

SummaryFifteen haemostasis parameters have been measured in 48 normal persons, 36 diabetics without and 44 with complications and 27 with peripheral arterial disease. Since the patients groups are older than normals, part of the differences are due to age. However, the differences are significant between normals and patients. They become highly significant for the diabetics with complications and nephropathy (Table 7). In diabetics without complications factor VIII functions, fibrinogen and thrombin time are related to age whereas there is a negative correlation for the fibrinolytic activity and antithrombin III. The diabetic complications shade off the correlations, which subsist only for VIIIR: CoF, VIIIR: Ag, ATIII and lysis before stasis. With Hbalc as dependent variable VIIIR:CoF is the only significant predictor variable in diabetics (Table 9).

scholarly journals Coagulation and Bleeding Disorders: Review and Update

2000 ◽  
Vol 46 (8) ◽  
pp. 1260-1269 ◽  
Author(s):  
Douglas A Triplett
Keyword(s):  
Laboratory Tests ◽  
Platelet Adhesion ◽  
Vascular Wall ◽  
Activated Partial Thromboplastin Time ◽  
Thrombin Time ◽  
Bleeding Disorders ◽  
Coagulation Proteins ◽  
Hereditary Disorders ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract Hemostasis is initiated by injury to the vascular wall, leading to the deposition of platelets adhering to components of the subendothelium. Platelet adhesion requires the presence of von Willebrand factor and platelet receptors (IIb/IIIa and Ib/IX). Additional platelets are recruited to the site of injury by release of platelet granular contents, including ADP. The “platelet plug” is stabilized by interaction with fibrinogen. In this review, I consider laboratory tests used to evaluate coagulation, including prothrombin time, activated partial thromboplastin time, thrombin time, and platelet count. I discuss hereditary disorders of platelets and/or coagulation proteins that lead to clinical bleeding as well as acquired disorders, including disseminated intravascular coagulation and acquired circulating anticoagulants.

The Thrombin Protecting Function of a Complement Inhibitor in Human Plasma

1979 ◽  
Author(s):  
E.R. Podack ◽  
J.G. Curd ◽  
J.H. Griffin ◽  
H.J. Müller-Eberherd
Keyword(s):  
Complex Formation ◽  
Antithrombin Iii ◽  
Membrane Attack Complex ◽  
Protein S ◽  
Thrombin Time ◽  
Two Dimensional ◽  
Complement Inhibitor ◽  
Functional Studies ◽  
Sds Page ◽  
At Iii

S-protein (S) is a newly discovered 80,000 MW plosma glycoprotein. It functions as an inhibitor of the membrane attack complex of complement. We now wish to report that S also functions as thrombin protecting factor in coagulation; S forms a reversible complex with thrombin which is more resistant to inactivation by antithrombin III (AT III) than thrombin alone. An S-thrombin complex and on S-throm-bin-AT III complex were formed in clotted plasma and with isolated proteins as demonstrated by two dimensional Immunoelectrophoresis. Functional studies measuring the esterolytic or clotting activity of thrombin showed that S in the presence and absence of heparin decreased the rate of inactivation of thrombin by AT III. Similar results were observed using plasma. For example, in the presence of 0.04 u/ml heparin and 1.6 u/ml thrombin, the thrombin time of plasma depleted in S was 150 sec. as opposed to 15 sec. when the plasma was reconstituted with purified S. That this effect of S was due to a decreased inactivation of thrombin by AT III was demonstrated directly by SDS-PAGE analysis of plasma containing 125l-thrombin. In the presence of S the rate of formation of the 95,000 dalton 125I-thrombin-AT III complex was markedly decreased compared to the rate of complex formation in the S-depleted plasma. These data suggest that S may modulate the interactions of thrombin and AT III.

COAGULATION ABNORMALITIES IN LEAD EXPOSED RATS

1987 ◽  
Author(s):  
Narendra Kumar Satija ◽  
Har Bhajan Singh ◽  
Anjana Grover ◽  
Ram Mohan Rai
Keyword(s):  
Modern Technology ◽  
Environmental Pollutant ◽  
The Body ◽  
Albino Rats ◽  
Thrombin Time ◽  
Significant Prolongation ◽  
Lysis Time ◽  
Industrial Material ◽  
Euglobulin Lysis Time ◽  
Plasma Recalcification Time

The accelerated rate of development of modern technology has greatly expanded the range of health hazards. Lead, a widely used industrial material, is a significant environmental pollutant that contaminates food, water, soil and air. Although much progress has been made in elucidating its adverse effects on various systems of the body like hepatic, CNS, renal etc., its effect on coagulation remains to be established. In view of this an experimental study was carried out in animals to understand how lead influences hemostasis.Male albino rats were exposed to lead either acutely by administering 20 mg lead acetate per kg body weight daily i.p. for 3 days or chronically by administering lead through drinking water containing 5 ppm lead for 150 days. Acute exposure to lead caused severe coagulopathy characterized by significant prolongation of plasma recalcification time, decrease in platelet count and decreased wall adherence of blood, decreased fibrinogen and euglobulin lysis time and significant increase in prothrombin time, thrombin time, and partial thromboplastin time. Similar observations were found in chronically exposed animals. It is concluded that exposure to heavy metals like lead may lead to a state of hypocoagulability.

scholarly journals The Heparin Inhibiting Property of Brain Thromboplastin

1977 ◽  
Author(s):  
E.D. Gomperts ◽  
M. Zucker
Keyword(s):  
Prothrombin Time ◽  
Antithrombin Iii ◽  
Proteinase Inhibitors ◽  
Serine Proteinase ◽  
Weight Fraction ◽  
High Molecular Weight Fraction ◽  
Thrombin Time ◽  
Factor X ◽  
Heparin Resistance

Antithrombin III is one of the serine proteinase inhibitors of the plasma which has been shown to specifically inhibit thrombin as well as Factor X. Heparin acts via antithrombin III, the heparin cofactor, hence it is difficult to explain the relative insensitivity of the prothrombin time to the presence of heparin in plasma as both thrombin, ana Factox Xa are associated functionally with the prothrombin time. This insensitivity becomes more obvious on appreciating the extreme sensitivity to heparin of the activated partial thromboplastin time as well as the thrombin time. This communication reports the demonstration of heparin inhibiting action of brain thromboplastin. The response of the prothrombin time to heparin under various conditions, and the effect of brain thromboplastin obtained from various sources and by different preparative techniques on the action of heparin in vitvo have been studied. The heparin inhibiting activity was shown to parallel the tissue factor activity. It is heat labile, non-dialysable, destroyed by detergent activity and lies in a high molecular weight fraction of the brain thromboplastin preparation (>300,000). In addition to explaining certain in vitro phenomena, these observations may explain the previously observed heparin resistance in the generalised Schwartzman phenomenon.

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