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Plasma Matrix (plasma + matrix)

Distribution by Scientific Domains

Medical Sciences	50%
Chemistry	50%

Selected Abstracts

Plasma matrix metalloproteinase-3 level is an independent prognostic factor in stable coronary artery disease

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 9 2005
T. C. Wu
Abstract Background, Recent evidence suggests the important role of matrix metalloproteinases (MMPs) in the progression of atherosclerosis and development of clinical events. We assessed the prognostic value of different plasma MMPs in patients with stable coronary artery disease (CAD). Materials and methods, A total of 165 consecutive nondiabetic patients with angiographically significant CAD (n = 150) or normal coronary angiograms despite exercise-induced myocardial ischemia (cardiac syndrome X, n = 15) and 17 normal subjects were evaluated. In each subject, plasma inflammatory markers including high sensitivity C-reactive protein (hsCRP) and MMP-2, 3 and 9 were measured. In CAD patients, major cardiovascular events including cardiac death, nonfatal myocardial infarction, unscheduled coronary revascularization and hospitalization as a result of unstable angina were prospectively followed up for more than 6 months. Results, Plasma levels of MMPs were significantly higher in CAD patients than in those with cardiac syndrome X and in normal subjects (MMP-2: 914·76 ± 13·20 vs. 830·79 ± 31·95 vs. 783·08 ± 28·40 ng mL,1, P = 0·002; MMP-3: 129·59 ± 4·21 vs. 116·86 ± 8·09 vs. 91·71 ± 9·55 ng mL,1, P = 0·011; MMP-9: 31·42 ± 2·84 vs. 11·40 ± 5·49 vs. 6·71 ± 2·89 ng mL,1, P = 0·006). In CAD patients, there were 48 major cardiovascular events during a mean follow-up period of 17·74 ± 0·85 months. The numbers of diseased vessels (HR = 2·19, 95% CI 1·20,1·02, P = 0·011), plasma hsCRP (HR = 2·21, 95% CI 1·18,4·11, P = 0·013) and MMP-3 level (HR = 2·46, 95% CI = 1·15,5·28, P = 0·021) were associated with the development of cardiovascular events. However, only the plasma MMP-3 level was an independent predictor of the adverse events in CAD patients (HR = 2·47, 95% CI 1·10,5·54, P = 0·028). Conclusions, Plasma MMP levels were increased in CAD patients. Plasma MMP-3 level, rather than hsCRP, was an independent prognostic marker for future cardiovascular events, suggesting its potential role in risk stratification and clinical management of stable CAD. [source]

Suppression of plasma matrix metalloproteinase-9 following montelukast treatment in childhood asthma

PEDIATRICS INTERNATIONAL, Issue 6 2007
SHIH-SUNG CHUANG
Abstract Background: Montelukast and ketotifen are commonly prescribed anti-inflammatory medications used in the treatment of childhood asthma. Methods: To investigate the modulation effect of montelukast and ketotifen, the levels of exhaled nitric oxide (eNO) and plasma matrix metalloproteinase-9 (MMP-9) were analyzed in a group of 30 children with mild persistent asthma. Results: Patients on montelukast therapy for 8 weeks had significantly decreased levels of eNO and plasma MMP-9, which were associated with improved symptoms and enhanced peak expiratory flow but not significantly associated with increased level of tissue inhibitor metalloproteinase-1 (TIMP-1). In contrast, treatment with ketotifen produced no significant changes in these parameters until 4,6 weeks into the therapy and no effect on plasma MMP-9. Conclusion: Leukotriene antagonists, such as montelukast, may be better non-steroidal anti-inflammatory drugs for preventing airway inflammation in mild childhood asthma. [source]

Liquid chromatography/electrospray ionization tandem mass spectrometry validated method for the simultaneous quantification of sibutramine and its primary and secondary amine metabolites in human plasma and its application to a bioequivalence study

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 23 2006
Deepak S. Jain
A high-throughput and sensitive bioanalytical method using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) has been developed for the estimation of sibutramine and its two metabolites (M1 and M2). The extraction of sibutramine, its metabolites and imipramine (internal standard (IS)) from the plasma involved treatment with phosphoric acid followed by solid-phase extraction (SPE) using a hydrophilic-lipophilic balanced HLB cartridge. The SPE eluate without drying and reconstitution was analyzed by LC/MS/MS, equipped with a with turbo ion spray (TIS) source, operating in the positive and multiple reaction monitoring (MRM) acquisition mode. Sample preparation by this method yielded extremely clean extracts with quantitative and consistent mean recoveries; 95.12% for sibutramine, 92.74% for M1, 95.97% for M2 and 96.60% for the IS. The total chromatographic run time was 3.0,min with retention times of 2.51, 2.13, 2.09,min for sibutramine, M1, M2 and imipramine, respectively. The developed method was validated in human plasma matrix, with a sensitivity of 0.1,ng/mL (coefficient of variance (CV), 2.07%) for sibutramine, 0.1,ng/mL (CV, 3.59%) for M1 and 0.2,ng/mL (CV, 4.93%) for M2. Validation of the method for its accuracy, precision, recovery, matrix effect and stability was carried out especially with regard to real subject sample analysis. The response was linear over the dynamic range 0.1 to 8.0,ng/mL for sibutramine and M1, and 0.2 to 16.0,ng/mL for M2 with correlation coefficients of r,,,0.9959 (sibutramine), 0.9935 (M1) and 0.9943 (M2). The method was successfully applied for bioequivalence studies in 40 human subjects with 15,mg capsule formulations. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Salting-out assisted liquid/liquid extraction with acetonitrile: a new high throughput sample preparation technique for good laboratory practice bioanalysis using liquid chromatography,mass spectrometry

BIOMEDICAL CHROMATOGRAPHY, Issue 4 2009
Jun Zhang
Abstract Acetonitrile, an organic solvent miscible with aqueous phase, has seen thousands of publications in the literature as an efficient deproteinization reagent. The use of acetonitrile for liquid,liquid extraction (LLE), however, has seen very limited application due to its miscibility with aqueous phase. The interest in LLE with acetonitrile has been pursued and reported in the literature by significantly lowering the temperature of the mixture or increasing the salt concentration in the mixture of acetonitrile and aqueous phase, resulting in the separation of the acetonitrile phase from aqueous phase, as observed in conventional LLE. However, very limited application of these methods has been reported. The throughput was limited. In this report, we report a new sample preparation technique, salting-out assisted liquid,liquid extraction with acetonitrile, for high-thoughput good laboratory practice sample analysis using LCMS, Two compounds from an approved drug, Kaletra®, were used to demonstrate the extractability of drugs from human plasma matrix. Magnesium sulfate was used as the salting-out reagent. Extracts were diluted and then injected into a reversed phase LC-MS/MS system directly. One 96-well plate was extracted with this new approach to evaluate multiple parameters of a good laboratory practice analytical method. Results indicate that the method is rapid, reliable and suitable for regulated bioanalysis. With minimal modification, this approach has been used for high-throughput good laboratory practice analysis of a number of compounds under development at Abbott. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Development and validation of a high-sensitivity liquid chromatography/tandem mass spectrometry (LC/MS/MS) method with chemical derivatization for the determination of ethinyl estradiol in human plasma,

BIOMEDICAL CHROMATOGRAPHY, Issue 7 2004
Wilson Z. Shou
Abstract An ultra-sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the analysis of oral contraceptive ethinyl estradiol (EE) was developed and validated over the curve range of 2.5,500 pg/mL using 1 mL of human plasma sample. Ethinyl estradiol and the internal standard, ethinyl estradiol tetra-deuterated (EE-d4), were extracted from the plasma matrix with methyl t -butyl ether, derivatized with dansyl chloride and then back-extracted into hexane. The hexane phase was evaporated to dryness, reconstituted and injected onto the LC/MS/MS system. The chromatographic separation was achieved on a Luna C18 column (50 × 2 mm, 5 µm) with an isocratic mobile phase of 20:80 (v/v) water:acetonitrile with 1% formic acid. The of,ine derivatization procedure introduced the easily ionizable tertiary amine function group to EE. This greatly improved analyte sensitivity in electrospray ionization and enabled us to achieve the desired lower limit of quantitation at 2.5 pg/mL. This high sensitivity method can be used for therapeutic drug monitoring or supporting bio-equivalence and drug,drug interaction studies in human subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source]