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)

We assessed the analytical performance of the co-immobilized hexokinase (EC 2.7.1.1) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) method for D-glucose analysis on the Technicon SMAC. The enzyme-containing coils were usable for one month, or 12 000 tests. Bilirubin, hemoglobin, lipemia, creatinine, uric acid, citric acid, and ascorbic acid did not interfere. Results with this method were compared to those by the National Glucose Reference Method. The upper limits of the total error estimate (a combination of random and systematic errors) were 76, 74, and 125 mg/liter at concentrations of 500, 1200, and 3000 mg/liter, respectively. The error estimates were less than allowable errors based on medical usefulness; thus the method was judged to perform acceptably with respect to the Reference Method. We also present performance data for the routine SMAC glucose oxidase (EC 1.1.3.4)/Peroxidase (EC 1.11.1.7) 3-methyl-2-benzothianolinone hydrazone-N,N-dimethylaniline method, the direct hexokinase method with the Du Pont aca, and the glucose oxidase oxygen-rate method with the Beckman Glucose Analyzer.
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PMID:Evaluation of the co-immobilized hexokinase/glucose-6-phosphate dehydrogenase method for glucose, as adapted to the Technicon SMAC. 65 1

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

The performance of the Reflotron system (Boehringer Mannheim) for the determination of urate in whole blood and serum was evaluated. Within-run and day-to-day imprecision of the system were comparable with those for a solution-chemistry enzymatic method (overall CVs in the range 2.2-2.5%). Results for 100 individual specimens with urate concentrations ranging from 16 to 134 mg/L agreed well with the comparison method, both for serum and whole blood. We saw no significant interference from lipemia or hemoglobin. Bilirubin interfered at concentrations greater than 100 mg/L. Hematocrit variation between 25% and 55% did not affect results for whole blood; variation of the applied sample volume from 28 microL to 35 microL (stated sample volume requirement: 30 microL) did not significantly influence the measured value. We consider results produced by the system to be of the same analytical quality as those obtained by the more conventional solution-chemistry methods that are currently available.
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PMID:Evaluation of determination of uric acid in serum and whole blood with the Reflotron. 283 55

We compared the Du Pont aca (phosphotungstate-enzymic cholesterol) and the Dow (dextran sulfate/Mg2+-enzymic cholesterol) methods for the determination of high-density lipoprotein cholesterol (HDLC) and total cholesterol in serum from 113 patients. The aca results for both total cholesterol and HDLC were significantly greater (p less than 0.0001) than the Dow results, the aca method overestimating the HDLC concentration (mean recovery 107.2% in serum samples with values assigned by the Centers for Disease Control). The precision of the aca method for HDLC was essentially the same as that of the Dow method. Bilirubin (up to 0.17 g/L), hemoglobin (up to 4 g/L), and slight lipemia (triglycerides up to 5.4 g/L) did not interfere with the aca method.
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PMID:Comparison of the Du Pont aca and Dow methods for determination of high-density lipoprotein cholesterol. 619 5

We evaluated the Du Pont Particle-Enhanced Turbidimetric Inhibition Immunoassay (PETINIA) for theophylline. The imprecision (CV) of the assay was less than 4.7% between-run and less than 3.6% within-run for theophylline concentrations between 5 and 30 mg/L. Standard curves for the assay were linear for theophylline concentrations from 0 to 46 mg/L and were stable throughout the study (i.e., for at least three months). The monoclonal antibody against theophylline used in this assay increases specificity; of the possibly interfering drugs, metabolites, and anticoagulants tested, only 1,3-dimethyluric acid and EDTA showed measurable effects. Bilirubin (less than 300 mg/L), hemoglobin (less than 6 g/L), or lipemia (triglycerides less than 6 g/L) does affect the quality of the assay. Analytical recovery of theophylline added to serum (5 to 40 mg/L) averaged 98% (range 93% to 112%). Comparison of results for patients' sera by the PETINIA method with those by enzyme immunoassay (EMIT) and by "high-performance" liquid chromatography yielded slopes and intercepts not significantly different from 1.0 and 0.0, respectively, and correlation coefficients ranging from 0.986 to 0.995.
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PMID:Particle-enhanced turbidimetric inhibition immunoassay for theophylline evaluated with the Du Pont aca. 638 31

We have evaluated a fully automated thyroxine assay involving the use of a homogeneous enzyme assay and a Technicon AutoAnalyzer II continuous flow system. Comparison by regression analysis with a thyroxine radioimmunoassay kit method gave a slope of 0.82 and a y-intercept of 7.81 micrograms/L (SE 0.86 microgram/L, r = 0.95). Within-run precision yielded CVs of 1.0-6.1%, between-day CVs were 2.0-14.4%; within-day precision showed a mean variance of 7.81 micrograms/L. Mean analytical recovery was 96.1%. Bilirubin, hemoglobin, and lipemia interfered with quantitation of results when their concentrations exceeded 50 mg/L, 300 mg/L, and 5 g/L, respectively. The reference interval for euthyroid status was calculated to be 50-110 micrograms/L. Sensitivity was 5.0 micrograms/L with a mean carryover of 1.65%. Current reagent and labor costs for enzyme immunoassay ($0.40) were less than for the manual radioimmunoassay procedure ($0.40) were less than for the manual radioimmunoassay procedure ($1.70). The assay is economical, simple to perform, and amenable to high-throughput thyroid screening in the routine laboratory.
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PMID:Continuous-flow enzyme immunoassay for thyroxine in serum. 701 33

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

A rapid and reliable method for measuring serum albumin employing bromcresol green is described. The addition of albumin to a solution of bromcresol green in a 0.075 M succinate buffer pH 4.20 results in an increase in absorbance at 628 nm. The absorbance-concentration relationship is linear for samples containing up to 6 g/dl albumin. Bilirubin, moderate lipemia, and salicylate do not interfere with the analysis. The use of nonionic surfactant (Brij-35) reduces the absorbance of the blank, prevents turbidity and provides linearity. The results by this method agree very well with those obtained by electrophoresis and salt fractionation. The method is simple, it has excellent precision and the reagents are stable. A protein standard is introduced which can be employed for both the total serum proteins and albumin determinations.
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PMID:Albumin standards and the measurement of serum albumin with bromcresol green. 1971. 904 40

Cellulomonas has been shown to be a good source of cholesterol oxidase in addition to Streptomyces for serum cholesterol determination by the endpoint method, inexpensive in cost, and showing excellent performance. For clinical use, we have assessed the reliability of Cellulomonas reagent for cholesterol determination. We constructed the user-defined endpoint methods on three automated analyzers. The analytical performances (linearity, precision, recovery, interference, stability, and comparison with the standardized method) of Cellulomonas cholesterol reagents were evaluated and compared to those of Streptomyces reagents. Linearity (18.1-23.3 mmol/L) and stability of reagents (6-11 weeks) depended on the analyzers being used. The average within-run and between-day % coefficients of variation (CVs) ranged from 1.44 to 2.45 and 1.98 to 2.99, respectively, and were within National Cholesterol Education Program analytical criteria (<or=3%). All assays using both reagents compared favorably with the commercial method and appeared accurate near the clinical decision cut-points. Hemoglobin concentration at 7.5 g/L only affected the assay using single wavelength measurement. Bilirubin decreased in serum cholesterol recovery while lipemia generated a positive interference with all methods. Cellulomonas enzyme is analytically reliable when used for serum cholesterol determination by the endpoint method. Its analytical performance is equivalent to Streptomyces enzymes and meets the analytical goals. It has an advantage over the other enzymes in that it does not ship in the frozen state.
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PMID:Implementation of cellulomonas cholesterol oxidase for total serum cholesterol determination by the endpoint method. 1820 May 84

Plasma bilirubin testing is crucial to prevent the occurrence of neonatal kernicterus. Haemolysis may occur during sampling and interfere with bilirubin determination. Moreover, lipidic infusions may induce plasma lipemia and also interfere with bilirubin measurement. We evaluated the interference of haemolysis and lipemia with three methods of total and direct bilirubin measurement adaptated on an Advia 1650 analyser (Siemens Medical Solutions Diagnostics) : Synermed (Sofibel), Bilirubin 2 (Siemens) and Bilirubin Auto FS (Diasys). The measurement of total bilirubin was little affected by haemolysis with all three methods. The Bilirubin 2 (Siemens) method was the less sensitive to haemolysis even at low bilirubin levels. The measurement of conjugated bilirubin was significantly altered by low heamoglobin concentrations for Bilirubin Auto FS(R) (30 microM or 0,192 g/100 mL haemoglobin) and for Synermed (60 microM or 0,484 g/100 mL haemoglobin). In marked contrast, we found no haemoglobin interference with the Direct Bilirubin 2 reagent which complied with the method validation criteria from the French Society for Biological Chemistry. The lipemia up to 2 g/L of Ivelip did not affect neither the measurement of total bilirubin for all three methods nor the measurement of conjugated bilirubin with the Diasys and Siemens reagents. However, we observed a strong interference starting at 0,5 g/L of Ivelip with the Synermed reagent. Our data suggest that both Siemens and Diasys methods allow to measure accurately total and conjugated bilirubin in hemolytic and lipemic samples, nevertheless, the Siemens methodology is less affected by these interferences.
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PMID:[Haemolysis and turbidity influence on three analysis methods of quantitative determination of total and conjugated bilirubin on ADVIA 1650]. 1839 Apr 27


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