The Plasmin Inhibitors of Plasma

1964 ◽  
Vol 12 (01) ◽  
pp. 119-125 ◽  
Author(s):  
Y Shamash ◽  
A Rimon
Keyword(s):  
Human Plasma ◽  
New Method ◽  
Normal Amount ◽  
Caseinolytic Activity ◽  
Before And After ◽  
Plasmin Inhibitors

SummaryA new method for the assay of plasmin inhibitors in human plasma is described. The method consists of determination of the caseinolytic activity of a standard plasmin solution before and after incubation with the inhibitor, with lysine added to the mixture as a stabilizer of plasmin. Using this method, it was found that plasma contains enough inhibitors to inactivate 30 caseinolytic units of plasmin, or 10 times the normal amount of plasminogen in human plasma.

DETERMINATION OF FREE CIRCULATING t PA AND MAXIMAL t PA CONTENT IN NORMAL HUMAN PLASMA USING A SPECTROPHOTO-METRIC METHOD

1987 ◽  
Author(s):  
B Boutière ◽  
D Arnoux ◽  
J Sampol ◽  
C Masson ◽  
F Hamon ◽  
...  
Keyword(s):  
Human Plasma ◽  
Solid Phase ◽  
Venous Occlusion ◽  
Affinity Separation ◽  
Human Volunteers ◽  
Before And After ◽  
Normal Human ◽  
Plasmin Inhibitors ◽  
Fibrinolytic Potential

Recent studies indicate that tPA released by endothelial cells circulates in plasma as a complex with its inhibitor (PAI). Quantitative data have been difficult to obtain however, due to the interference of plasmin inhibitors and other activators on liquid-phase tPA assays. In the present study an activity test (SOFIA-tPA ; Anal. Biochem. 133:201, 1986) on solid-phase fibrin has been used to determine the physiological forms of tPA in normal plasma. In this assay an affinity separation step allows the selective binding of tPA to fibrin and the elimination of plasmin inhibitors and other activators (pro UK, UK). Fibrin-boypd tPA is subsequentely detected by adding plasminogen and a chromogenic substrate selective for plasmin. Under these conditions the reaction rate depends on the presence of tPA, tPA-PAI complexes and PAI present in plasma. Plasma from 38 normal human volunteers obtained before and after venous occlusion was tested. Free tPA was determined in undiluted plasma while the fibrinolytic potential (maximal tPA activity) of plasma was detected following dissociation of tPA-PAI complexes by dilution and acidification of plasma, i.e. euglobulin fractionation. A 1:2 to 1:5 dilution of euglobulins was necessary to obtain a maximal dissociation of precipitated complexes. A similar dilution induced dissociation of tPA-PAI complexes was obtained with plasma at pH 6.8. The amount of free detectable tPA increased as a function of the dilution of plasma until a plateau value (usually at dilution 1:20), which was similar to that observed with the euglobulins. Our results (see Table) indicate that most of the tPA in human plasma circulates as tPA-PAI complexes and that free tPA can be detected only in minute amounts. Plasma instead of euglobulins can be accurately used to detect both free (undiluted plasma) and total tPA (plasma diluted 1:20).

scholarly journals NEW METHOD DEVELOPMENT AND VALIDATION FOR THE DETERMINATION OF FEBUXOSTAT IN HUMAN PLASMA BY LIQUID CHROMATOGRAPHY–MASS SPECTROMETRY

2016 ◽  
Vol 8 (9) ◽  
pp. 61 ◽  
Author(s):  
Narottam Pal ◽  
Avanapu Srinivasa Rao ◽  
Pigilli Ravikumar
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Human Plasma ◽  
Method Development ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
New Method ◽  
Liquid Chromatography Mass Spectrometry ◽  
Chromatography Mass Spectrometry

<p><strong>Objective</strong>:<strong> </strong>To develop a new method and validate the same for the determination of Febuxostat (FBS) in human plasma by liquid chromatography–mass spectrometry (LCMS).</p><p><strong>Methods</strong>:<strong> </strong>The present method utilized reversed-phase high-performance liquid chromatography with tandem mass spectroscopy. Febuxostat D9 (FBS D9) was used as internal standard (IS). The analyte and internal standard were separated from human plasma by using solid phase extraction method. Zorbax Eclipse XDB, C<sub>8</sub>, 100 mm x 4.6 mm, 3.5 µm column was used and HPLC grade acetonitrile, 5 millimolar (mM) ammonium format (80: 20, v/v) as mobile phase, detected by mass spectrometry operating in positive ion and multiple reaction monitoring modes.</p><p><strong>Results</strong>:<strong> </strong>The parent and production transitions for FBS and internal standard were at m/z 317.1→261.0 and 326.1→262.0 respectively. The method was validated for system suitability, specificity, carryover effect, linearity, precision, accuracy, matrix effect, sensitivity and stability. The linearity range was from 20.131 ng/ml to10015. 534 ng/ml with a correlation coefficient of 0.999. Precision results (%CV) across six quality control samples were within the limit. The percentage recovery of FBS and internal standard from matrix samples was found to be 76.57% and 75.03% respectively.</p><p><strong>Conclusion</strong>:<strong> </strong>Present study describes new LC-MS method for the quantification of FBS in a pharmaceutical formulation. According to validation results, it was found to be a simple, sensitive, accurate and precise method and also free from any kind of interference. Therefore the proposed analytical method can be used for routine analysis for the estimation of FBS in its formulation.</p>

A new method for the determination of prothrombin in human plasma

1990 ◽  
Vol 57 (5) ◽  
pp. 705-715 ◽  
Author(s):  
Akiko Hijikata-Okunomiya
Keyword(s):  
Human Plasma ◽  
New Method

Spectrophotometrical determination of plasminogen and plasmin inhibitors in human plasma using fibrin suspension as a substrate

1980 ◽  
Vol 20 (3) ◽  
pp. 307-313 ◽  
Author(s):  
Yuji Saito ◽  
Shozo Kanai ◽  
Kenji Takabayashi ◽  
Yuji Inada
Keyword(s):  
Human Plasma ◽  
Plasmin Inhibitors

A new method for the determination of the binding capacity of testosterone-estradiol-binding-globulin in human plasma

1973 ◽  
Vol 4 (5) ◽  
pp. 537-550 ◽  
Author(s):  
V.P. Shanbhag ◽  
R. Södergård ◽  
H. Carstensen ◽  
P.Å. Albertsson
Keyword(s):  
Human Plasma ◽  
Binding Capacity ◽  
New Method

Fibrinolytic and Esterolytic Activity of Human Plasma

1965 ◽  
Vol 13 (02) ◽  
pp. 484-491
Author(s):  
D. M Adamis ◽  
G. M Maniatis
Keyword(s):  
Simultaneous Determination ◽  
Human Plasma ◽  
Total Activity ◽  
Satisfactory Method ◽  
Acetone Treatment ◽  
Before And After ◽  
Esterolytic Activity ◽  
Hydrolysis Of

SummaryThe fibrinolytic and esterolytic activity of the plasma before and after activation with Streptokinase is studied. The inhibitors of plasmin are neutralized by the acidification of the plasma or by the acetone treatment. The inhibitors of the “trypsin like enzymes” are neutralized only by acetone. The hydrolysis of the BAEE by the acetone treated and activated plasma seems to be a satisfactory method for the simultaneous determination of the total (plasmin-plasminogen) activity and the total activity of the (trypsin like enzymes) with arginine exopeptidase activity.

scholarly journals Simultaneous Determination of Tocotrienols, Tocopherols, Retinol, and Major Carotenoids in Human Plasma

2003 ◽  
Vol 49 (12) ◽  
pp. 2056-2066 ◽  
Author(s):  
Bee-Lan Lee ◽  
Ai-Li New ◽  
Choon-Nam Ong
Keyword(s):  
Simultaneous Determination ◽  
Human Plasma ◽  
Signal To Noise Ratio ◽  
Column Switching ◽  
Antioxidant Vitamins ◽  
New Method ◽  
Fluorometric Detection ◽  
Photodiode Array Detection ◽  
Wide Range

Abstract Background: Epidemiologic evidence suggests that the concentrations of antioxidant vitamins in human plasma may play an important role in numerous chronic diseases, such as cancer and cardiovascular disease. However, methods for simultaneous measurement of these antioxidants are scarce. We developed and validated a new HPLC method for simultaneous determination of these vitamers in human plasma that uses a novel column-switching approach. Methods: The new method uses liquid–liquid extraction and isocratic separation with two monomeric C18 columns maintained at 35 and 4 °C coupled with ultraviolet–visible and fluorometric detection. This method could separate 14 vitamers and 3 internal standards within 27 min. No additional modifier was required; the mobile phase was acetonitrile–methanol (65:35 by volume), and the flow rate was 1 mL/min. Results: For photodiode array detection, the detection limits (signal-to-noise ratio &gt;3) were 0.02 mg/L for β-carotene, lutein, zeaxanthin, and canthaxanthin; 0.01 mg/L for all-trans-retinol, β-cryptoxanthin, α-carotene, and lycopene; and 0.1 mg/L for all tocopherols and tocotrienols. The detection limit was at least 25-fold lower (0.004 mg/L) when fluorometry was used for measurement of δ-, γ-, and α-tocotrienol and δ-tocopherol compared with ultraviolet detection. The recovery and imprecision of the assay were generally &gt;90% and &lt;10%, respectively. Conclusions: This new method separates a wide range of fat-soluble antioxidant vitamins in human plasma, including six carotenoids, three isoforms of tocotrienols and tocopherols (δ-, γ-, and α-), and all-trans-retinol. The overall findings suggest that our method is faster, more sensitive, and more comprehensive than existing methods.

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