Barium-sulfate

SummaryIn this paper an inhibitor is described that is found in hemophilic plasma and serum different from any till now described inhibitor. The inhibitor only inhibits prothrombin activation in the “intrinsic clotting systems”. This inhibitor is probably not present in normal human plasma or serum. It is destroyed by ether and freeze drying, is labile to acid and storage at room temperature. It is stable upon dialysis and has not been adsorbed on barium sulfate, aluminum hydroxide or kaolin. It precipitates at 50% v/v saturation with alcohol. The nature of this inhibitor seems to be a protein or lipoprotein.Factor VIII was isolated from hemophilic plasma. The amount isolated was the same as from normal plasma and the activity properties were not different. Hemophiliacs have normal amounts of factor VIII.

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“In vitro” Neutralization with Oxalate Ion of the Anticoagulant Effect of Heparin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654928 ◽

1961 ◽

Vol 05 (02) ◽

pp. 314-318 ◽

Cited By ~ 1

Author(s):

W. O Cruz ◽

L Meis ◽

C. P Dietrich

Keyword(s):

Calcium Oxalate ◽

Aluminium Hydroxide ◽

Barium Sulfate ◽

Anticoagulant Effect ◽

Normal Plasma ◽

Oxalate Ion

SummaryHeparinized blood or plasma coagulates if, after addition of oxalate, recalcification follows. Of the decalcifying agents only oxalate ion has been suitable for demonstrating this phenomenon. Oxalate seem to accomplish two different roles connected with this effect: a fundamental one, i. e., to sensitize a heparinlipoprotein complex to the action of an anti-heparin factor found in normal plasma or serum and a secondary one, related to its capacity to adsorb this antiheparin factor. The latter is removable by centrifugation. This anti-heparin oxalate factor, which is able to counteract the action of heparin after previous addition of oxalate, was found in sequestrened, Dowex 50 resin plasma or in serum, but is not active in citrated plasma. This factor was removed from plasma by adsorption with barium sulfate, aluminium hydroxide or calcium oxalate and was eluted from these adsorbants after incubation with saline.

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A Simple Method for Preparing Fibrinogen

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655637 ◽

1966 ◽

Vol 16 (01/02) ◽

pp. 198-206 ◽

Cited By ~ 26

Author(s):

W Straughn ◽

R. H Wagner

Keyword(s):

Barium Sulfate ◽

Caproic Acid ◽

Aminobutyric Acid ◽

Gamma Aminobutyric Acid ◽

Human Fibrinogen ◽

Simple Method ◽

High Yields ◽

Marked Stability

SummaryA simple new procedure is reported for the isolation of canine, bovine, porcine, and human fibrinogen. Two molar β-alanine is used to precipitate fibrinogen from barium sulfate adsorbed plasma. The procedure is characterized by dependability and high yields. The material is 95% to 98% clottable protein but still contains impurities such as plasminogen and fibrin-stabilizing factor. Plasminogen may be removed by adsorption with charcoal. The fibrinogen preparations exhibit marked stability to freezing, lyophilization, and dialysis. Epsilon-amino-n-caproic acid and gamma-aminobutyric acid which were also studied have the property of precipitating proteins from plasma but lack the specificity for fibrinogen found with β-alanine.

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Crystallization Behavior and Mechanical Properties of Poly(ε-caprolactone) Reinforced with Barium Sulfate Submicron Particles

Materials ◽

10.3390/ma14092368 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2368

Author(s):

Hegoi Amestoy ◽

Paul Diego ◽

Emilio Meaurio ◽

Jone Muñoz ◽

Jose-Ramon Sarasua

Keyword(s):

Barium Sulfate ◽

Thermal Studies ◽

Polarized Light ◽

Optical Microscope ◽

Submicron Particles ◽

Degree Of Crystallinity ◽

Scanning Calorimetry ◽

Nucleation Effect ◽

Crystal Fraction ◽

Light Optical Microscope

Poly(ε-caprolactone) (PCL) was mixed with submicron particles of barium sulfate to obtain biodegradable radiopaque composites. X-ray images comparing with aluminum samples show that 15 wt.% barium sulfate (BaSO4) is sufficient to present radiopacity. Thermal studies by differential scanning calorimetry (DSC) show a statistically significant increase in PCL degree of crystallinity from 46% to 52% for 25 wt.% BaSO4. Non-isothermal crystallization tests were performed at different cooling rates to evaluate crystallization kinetics. The nucleation effect of BaSO4 was found to change the morphology and quantity of the primary crystals of PCL, which was also corroborated by the use of a polarized light optical microscope (PLOM). These results fit well with Avrami–Ozawa–Jeziorny model and show a secondary crystallization that contributes to an increase in crystal fraction with internal structure reorganization. The addition of barium sulfate particles in composite formulations with PCL improves stiffness but not strength for all compositions due to possible cavitation effects induced by debonding of reinforcement interphase.

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