Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies are reported on the reaction kinetics of the glucose assay according to Trinder which involves the specific oxidation of glucose by glucose oxidase and the determination of the hydrogen peroxide released by means of phenol and 4-aminophenazone in the presence of peroxidase. The results have been used to develop a general kinetic fixed-time method for the analysis of glucose in whole blood and serum. The single reagent method has been adapted to the ENI GEMSAEC centrifugal analyzer and to the Abbott ABA-100 analyzer. The procedures exhibited excellent precision and the results correlated well with those obtained by the hexokinase method, Linearity was achieved from 3 to 64 mmol/1 glucose for the GEMSAEC method, and from 3 to 33 mmol/1 glucose for the ABA-100 method. Reagent or sample blank corrections were not necessary. There were no interferences from various drugs, hemoglobin, bilirubin, or lipemia.
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PMID:Kinetic enzymatic method for automated determination of glucose in blood and serum. 83 60

We describe the effects of uric acid, hemolysis, drugs, ascorbic acid, lipemia, and bilirubin on the enzymic measurement of cholesterol in serum by use of reagent kits from Abbott, Beckman, Boehringer Mannheim, Calbiochem, and Worthington. In all of these, the chromogen formed from the reaction of hydrogen peroxide with phenol and 4-aminoantipyrene is measured. The absorbance was measured at 500 nm vs. a serum blank for each kit--except Abbott's with which the recorded absorbances were the differences between readings at 500 and 600 nm. With all reagents kits, there was no interference from uric acid up to 200 mg/liter, hemoglobin up to 1.0 g/liter, or drugs (clofibrate, phenobarbital, Ketochol, Ovral-28), but negative interferences from ascorbic acid. Except for the Abbott kit, the cholesterol values obtained for lipemic samples were lower than found with the comparison method [Abell et al., Stand. Methods Clin. Chem. 2, 26 (1958)]. With Abbott's reagents, for most lipemic samples, the values were the same. Bilirubin at concentrations of 200 mg/liter significantly decreased the cholesterol values with Beckman, Calbiochem, and Worthington reagent kits. With Boehringer Mannheim reagent a small negative interference was observed and with Abbott reagent a small positive interference was observed when the bilirubin concentrations were 200 mg/liter.
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PMID:Interference with the enzymic measurement of cholesterol in serum by use of five reagent kits. 84 75

Hyperlipidemia interferes with spectrophotometric assays of a number of analytes. No interference was found in the assay of gentamicin, phenytoin, or phenobarbital due to turbidity in levels of triglyceride less than or equal to 2,000 mg/dl with the Abbott TDx or Syva enzyme multiplied immunoassay (EMIT) methods. There is no evidence that lipophilic drugs partition into the lipid phase in severely hyperlipidemic serum. No assay errors due to turbidity or partitioning of phenobarbital in the lipid of serum with a triglyceride concentration of 10,000 mg/dl were found, nor were changes seen in free phenytoin distribution due to hyperlipidemia.
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PMID:The effect of hyperlipidemia on therapeutic drug assays. 355 30

This spectrophotometric method for the direct determination of potassium in serum or plasma is based on the selective complexing of potassium by a specific macrocyclic polyether, with the subsequent formation of an ion-pair with a colored anion. The colored anion is extracted into an organic solvent, clarified by centrifugation, and then measured at 415 nm. The absorbance of the chromogen varies linearly with [K+] to at least 15 mmol/L. Results of this colorimetric method (y) correlate well with the results obtained by a flame-photometric method (y = 1.04x - 0.22, r = 0.97, n = 81), with CVs ranging from 2 to 4%. We observed no interferences from lipemia, added bilirubin, or various electrolytes. We also evaluated the use of this reagent in a new automated blood analyzer developed by Abbott, a two-dimensional centrifugal system (Clin Chem 31:1457-1463, 1985). Potassium determined with this system (y) correlated well with results by flame photometry: y = 1.02x + 0.02 (r = 0.94, n = 168). With this system one can use whole-blood specimens in measuring potassium.
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PMID:Colorimetric determination of potassium in whole blood, serum, and plasma. 402 95

The Abbott TDx fluorescence polarization immunoassay was evaluated for the determination of serum digoxin concentrations. Within-assay precision was less than 4% coefficient of variation (CV) for concentrations ranging from 0.64 to 3.75 ng/mL. Between-assay precision was 14.5% CV at 0.75 ng/mL, 5.7% CV at 1.50 ng/mL, and 4.9% CV at 3.48 ng/mL. Sensitivity to 0.2 ng/mL digoxin was confirmed. Correlation of 86 patient specimens assayed by radioimmunoassay (RIA) with the TDx showed the following: correlation coefficient r = 0.94, slope = 0.93, intercept = 0.11, and Sy/x = 0.19. Recovery from serum at concentrations of 0.97 ng/mL and 4.50 ng/mL averaged 98%. No significant interference from lipemia, icteria, or hemolysis was observed. Spironolactone showed no cross-reactivity with the antibody, while digitoxin exhibited significant cross-reactivity. Compared to the RIA procedure, the TDx assay was more rapid, reliable and, in this clinical situation, more cost effective.
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PMID:Analysis of digoxin concentrations in serum by fluorescence polarization immunoassay: an evaluation. 637 49

The Abbott TDx fluorescence polarization immunoassay (FPIA) system was evaluated and compared with well-established enzyme multiplied immunoassay technique (EMIT) and radioimmunoassay (RIA) methods utilizing five high-volume drug assays including theophylline, gentamicin, phenytoin, phenobarbital, and digoxin. These drug assays were evaluated for precision, calibration stability, specificity, and accuracy. Within-run precision studies utilizing control samples (n = 20) in the subtherapeutic, therapeutic, and toxic ranges resulted in coefficients of variation (CV) of less than 4.0% for the theophylline, gentamicin, phenytoin, and phenobarbital assays and of less than 9.5% for the digoxin assay. Between-run precision studies based on an initial TDx calibration curve over a 2-3 week period yielded CVs of less than 8% for all five drug assays. Cross-reactivity of the FPIA gentamicin assay with concurrently used aminoglycosides such as tobramycin and amikacin was less than 0.1%, and interference due to hemolysis and lipemia was negligible. Highly icteric specimens resulted in clinically significant decreases in theophylline and phenytoin concentrations, but this problem can be corrected by subtraction of blank intensity values. Comparison of the FPIA method with the EMIT and RIA methods indicated an extremely good analytical correlation (r greater than 0.97) for all five comparisons. The Abbott TDx FPIA system offers significant advantages in calibration and reagent stability, and greater sensitivity in the low drug concentration ranges while maintaining accuracy and precision comparable with those of established EMIT and RIA procedures.
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PMID:Clinical evaluation of the Abbott TDx fluorescence polarization immunoassay analyzer. 639 Jul 99

A procedure to measure total and direct bilirubin using the Abbott Bichromatic Analyser is described. The method is an adaptation of a sodium dodecyl sulfate method. Reaction products are measured at an acid pH in a buffered matrix using a 600-650 filter wheel. The method has very little spectral interference from either hemolysis or lipemia and correlates well with the manual Jendrassik-Grof method.
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PMID:A total and direct bilirubin determination using an SDS procedure on the Abbott Bichromatic Analyser. 661 11

We have extended fluorescence polarization immunoassay (FPIA) technology for the measurement of drugs to include the complex amphoteric glycopeptide antibiotic vancomycin (molecular weight, 1,449). Fluorescein-labeled vancomycin was employed as a tracer, and antisera specific for vancomycin were raised in rabbits by conventional procedures. Tracer, sample, and diluted antiserum were combined, and the polarization of tracer fluorescence is determined in a specially designed fluorometer (Abbott TDx). Because of instrument design, the possibility of fluorescent interferences is minimized. The assay can measure as little as 0.6 mg/L of vancomycin and is free of interferences from hemolysis, lipemia, bilirubin, and changes in protein concentration. The coefficient of variation within assay was 3% (n = 5) and between assays was 5% (n = 5). The FPIA assay (TDx Vancomycin) was compared to a liquid chromatographic (LC) assay for vancomycin and to a commercially available radioimmunoassay (RIA) for 98 clinical specimens. A linear least-squares regression analysis gave a correlation coefficient for LC of 0.980 from the equation FPIA = 1.09 LC + 3.04, and a correlation coefficient for RIA of 0.957 from the equation FPIA = 1.036 RIA + 1.66.
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PMID:Automated fluorescence polarization immunoassay for monitoring vancomycin. 663 61

A sensitive method (Clin. Chem. 26: 327--331, 1980) for serum iron, in which the color reagent Ferrozine is used, is modified and adapted to the Abbott ABA-100 discrete analyzer. The standard curve is linear to at least 10 mg/L and the method showed day-to-day precision (CV) of 2.4% for a 1.03 mg/L sample (n = 63) and 1.9% for a 2.13 mg/L sample (n = 63). Lower values were obtained than with the modified continuous-flow technique of Giovanniello et al., but the correlation was good (r = 0.98). Bilirubin and copper do not interfere; hemoglobin and gross lipemia interfere only slightly. The total iron-binding capacity, based on Ramsay's method, was evaluated with regard to the effect of adding various amounts of magnesium carbonate. Results led us to use a ratio of approximately 180 mg of magnesium carbonate to each 5 micrograms of excess iron added. Day-to-day, the method for total iron-binding capacity gave a CV of 3.1% for a 2.55 mg/L sample, 2.8% for a 3.63 mg/L sample.
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PMID:Ferrozine iron and total iron-binding capacity method adapted to the ABA-100 Bichromatic Analyzer. 727 7

The limits of quantitation of the assay of tobramycin in serum by the fluorescence polarization immunoassay system marketed by Abbott Laboratories (TDxFLx system) are 0.1 and 10.0 mg/L. For some pharmacokinetic studies, however, a more sensitive analysis is needed. The sensitivity of the TDxFLx system can theoretically be increased 10-fold by pipetting buffer solution into the sample well and 450 microliters serum into the predilution well. The assay modified in this way can be run with the usual calibration of the apparatus for normal analysis. The analytical performance of this modification of the TDxFLx assay was assessed. Tobramycin concentrations ranged from 0.01 to 1.0 mg/L. Analytical recovery ranged from 85 to 95%. The coefficients of variation for within-run and between-run precision ranged from 0.5% to 5% and from 2% to 6%, respectively, for control concentrations ranging from 0.05 to 0.75 mg/L. Based on recovery and precision results, the lower limit of quantitation was established as 0.025 mg/L. There was no significant detectable cross-reactivity from ceftazidime, aztreonam, flucloxacillin, cilastatin, or imipenem. There was a small, but significant cross-reactivity from gentamicin and netilmicin. Hyperbilirubinemia did not affect the assay, but hyperlipidemia gave falsely elevated results of the tobramycin assay. It was concluded that modification of the assay resulted in an acceptable method to quantify low concentrations of tobramycin in serum.
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PMID:Evaluation of a fluorescence polarographic immunoassay with increased sensitivity for measurement of low concentrations of tobramycin in serum. 872 Dec 83


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