Abstract:
:We assessed the performance of three commercially available polyclonal immunoassays for apparent cyclosporine in 120 whole-blood specimens collected from transplant recipients just before their next dose of cyclosporine (CsA). The assays were (a) Abbott's TDx fluorescent polarization immunoassay for CsA and its metabolites in whole blood; (b) the Sandoz radioimmunoassay (RIA); and (c) Incstar's Cyclo-Trac RIA. Mean respective CVs were 3.8%, 9.3%, and 24.3%. Analytical recovery was nearly 100% for concentrations up to 1000 micrograms/L for Incstar and up to 1500 micrograms/L for Abbott and Sandoz; linearity was compromised at greater concentrations. We also quantified the parent CsA concentrations by HPLC. Moreover, to follow day-to-day fluctuations in patients' "cyclosporine" concentrations with each method and to assess the impact these differences have on interpretation of the analytical results, we assayed serial specimens from six post-transplant patients. These showed significantly dissimilar, but parallel, results among the methods for any single sample. Occasionally, however, a result would not fit the established trend. Biases observed among the assays can be explained in part by the nonspecific antisera cross-reacting with CsA metabolites. Most important, we demonstrate that patients' results are not reliably interchangeable among the methods.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Strassman MJ,Lensmeyer GL,Wiebe DA,Carlson IHsubject
Has Abstractpub_date
1990-01-01 00:00:00pages
115-8issue
1eissn
0009-9147issn
1530-8561journal_volume
36pub_type
杂志文章abstract::Creatine kinase (CK; EC 2.7.3.2) has been used as an indicator of myocardial cellular damage. In this study we used a Krebs-Henseleit (KH) solution to reperfuse isolated rat hearts after 24 h of cold preservation and collected the KH reperfusate for assay of CK to assess cellular damage. We wanted to determine the sta...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract:BACKGROUND:Studies of the effects of tobacco smoke often rely on reported exposure to cigarette smoke, a measure that is subject to bias. We describe here the relationship between parental smoking exposure as assessed by urinary cotinine excretion and lung function in children with asthma. METHODS:We studied 90 childr...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::We evaluated the dual-precipitation method for quantitative measurement of lipoproteins as described by Wilson and Spiger [J. Lab. Clin. Med. 82, 473 (1973)] for normo- and hyperlipemic sera, by comparison with the results obtained with ultracentrifugation. If serum with an above-normal triglyceride concentration is a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-07-01 00:00:00
abstract::Two-hour postprandial specimens have a -14% proportional bias for lipoprotein(a) [Lp(a)], a -0.035 g/L systematic bias for apolipoprotein (apo) A-I, and a -9% proportional bias for apo B, compared with values in 12-h fasting specimens. Although a physiological hemodilution appears to account for a portion of these bia...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-03-01 00:00:00
abstract::Four commercial products for urine glucose determination were evaluated and compared with a quantitative hexokinase procedure. We examined precision, sensitivity, and analytical recovery of glucose from glucose-supplemented urine samples and comparison of methods, using patients' samples. Only "Chemstrip uG" (Bio-Dyna...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract::Using a cation-exchange chromatographic method, we found normal or subnormal values for glycosylated hemoglobin in a few diabetic patients with persistent hyperglycemia. Subsequent investigations revealed that these unexpected results had originated from black patients with diabetes. In view of common occurrence of ab...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-08-01 00:00:00
abstract::We investigated the efficiency, accuracy, and reliability of the ultrafiltration/dipstick methodology commonly used to diagnose myoglobinuria. Twenty-five myoglobin-containing urine specimens were filtered by centrifugation for 15 min at 1500g through a Centricon-30 membrane filter. Both the original specimen and filt...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-06-01 00:00:00
abstract:BACKGROUND:Epidemiologists have observed that blood donation is associated with decreased risk of type 2 diabetes and cardiovascular disease. METHODS:We investigated the relationship between iron stores and insulin sensitivity, after controlling for known confounding factors, and compared insulin sensitivity between b...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.046847
更新日期:2005-07-01 00:00:00
abstract::We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::A dissociation-enhanced lanthanide fluoroimmunoassay of serum cortisol based on time-resolved fluorescence is described. The assay is a direct assay, where cortisol immobilized on the wall of a microtiter-strip well competes with cortisol in the sample for the europium-labeled polyclonal antibody. The amount of bound ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-10-01 00:00:00
abstract:BACKGROUND:Published literature was systematically reviewed to determine the diagnostic accuracy of new protein markers of acute coronary syndromes (ACS) in symptomatic outpatients at low risk of ACS and related complications comparable to patients evaluated in emergency department chest pain units. METHODS:Studies we...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2005.052456
更新日期:2005-11-01 00:00:00
abstract::The objective of this study was to develop a clinical laboratory method for subclass typing of human immunoglobulin G (IgG) paraproteins. Serum proteins were isoelectrically focused (IEF) in a mini-gel and passively blotted by capillary diffusion onto untreated nitrocellulose. Unreacted sites on the nitrocellulose wer...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-03-01 00:00:00
abstract::We compared the ionic activity of sodium, as measured with glass electrodes, with sodium concentration in 23 healthy persons, 15 persons with acute renal failure, and before and after dialysis in 46 patients with chronic renal failure. In healthy persons the mean (+/- SEM) sodium concentration was 139.1 +/- 0.6 mmol/L...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-11-01 00:00:00
abstract::Hemoglobinometry according to the International Committee of Standardization in Hematology (ICSH) suffers from imprecision related to high sample dilution and from potential errors owing to sample turbidity. We have evaluated a new instrument, "HemoCue," that measures hemoglobin at two wavelengths as azide methemoglob...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-03-01 00:00:00
abstract::We describe a gas-chromatographic method for measuring chlorpromazine and its metabolites chlorpromazine sulfoxide, mono-N-desmethylchlorpromazine, and di-N-desmethylchlorpromazine at therapeutic concentrations in human serum, with use of a nitrogen detector. The compounds are extracted from serum at pH 10.5 into hexa...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-07-01 00:00:00
abstract:BACKGROUND:Detection of melanoma cells in circulation may be important in assessing tumor progression. The objective of this study was to develop a specific, reliable multimarker quantitative real-time reverse transcription-PCR (qRT) assay for detecting melanoma cells in patients' blood. METHODS:We developed qRT assay...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.045096
更新日期:2005-06-01 00:00:00
abstract:BACKGROUND:PCR-based detection of minimal residual disease (MRD) in neuroblastoma (NB) patients can be used for initial staging and monitoring therapy response in bone marrow (BM) and peripheral blood (PB). PHOX2B has been identified as a sensitive and specific MRD marker; however, its expression varies between tumors....
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.117945
更新日期:2009-07-01 00:00:00
abstract::A simple computer-based screening technique has been developed for classifying human expired air components into 16 chemical classes, based on empirical formulas. The sort procedure was developed to simplify the screening of the composition of expired air samples by sorting all components into chemical classes and cla...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-08-01 00:00:00
abstract:BACKGROUND:Plasma concentrations of the peptides midregional proadrenomedullin (MR-proADM), midregional proatrial natriuretic peptide (MR-proANP), and C-terminal endothelin-1 precursor fragment (CT-proET-1) are increased in various cardiovascular conditions. However, there is limited information about the association a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.193656
更新日期:2013-04-01 00:00:00
abstract:BACKGROUND:D-2-Hydroxyglutaric aciduria (D-2-HGA), L-2-hydroxyglutaric aciduria (L-2-HGA), and the combined D/L-2-hydroxyglutaric aciduria (D/L-2-HGA) are poorly understood organic acidurias. To investigate the usefulness of cultured human skin fibroblasts for both diagnostic and research purposes, we measured disease-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.7.1133
更新日期:2003-07-01 00:00:00
abstract::We evaluated the EMIT Cyclosporine Assay (Syva Co., Palo Alto, CA), using the Cobas-Mira analyzer to assess the precision, accuracy, and analytical recovery from whole-blood samples supplemented with cyclosporine. We also performed comparative analysis of whole-blood samples containing cyclosporine from liver and kidn...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract::We determined fluoxetine (Prozac) and its major metabolite norfluoxetine in plasma by liquid chromatography with fluorescence detection. After liquid-liquid extraction from 1 mL of plasma, the extract was derivatized at room temperature with dansyl chloride, and the highly fluorescent derivatives were chromatographed ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract:BACKGROUND:Newborn screening for deficiency in the lysosomal enzymes that cause Fabry, Gaucher, Krabbe, Niemann-Pick A/B, and Pompe diseases is warranted because treatment for these syndromes is now available or anticipated in the near feature. We describe a multiplex screening method for all five lysosomal enzymes tha...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.035907
更新日期:2004-10-01 00:00:00
abstract:BACKGROUND:The American Diabetes Association task force on standardization of insulin assays in 1996 showed wide variation in assay bias. Newer assays are specific for insulin, with several now available on automated immunoassay analyzers. METHODS:In 2004, we compared 11 commercially available insulin assays by analyz...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2006.077784
更新日期:2007-05-01 00:00:00
abstract:BACKGROUND:Standardization of clinical measurements of C-reactive protein (CRP) is based on the availability of reference materials. The serum protein reference material ERM-DA470 was used as a calibrant for various commercially available immunoassays but has now been exhausted. The recently released ERM-DA470k/IFCC wa...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.147124
更新日期:2010-09-01 00:00:00
abstract:BACKGROUND:Immune repertoire sequencing of the T-cell receptor can identify clonotypes that have expanded as a result of antigen recognition or hematological malignancies. However, current sequencing protocols display limitations with nonuniform amplification and polymerase-induced errors during sequencing. Here, we de...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa159
更新日期:2020-09-01 00:00:00
abstract::Urokinase plasminogen activator (uPA) is a serine protease causally involved in cancer invasion and metastasis. In this study, high concentrations of uPA in primary breast cancers were independently associated with both a shortened disease-free interval and overall survival. For the disease-free interval as endpoint, ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-06-01 00:00:00
abstract:BACKGROUND:Emerging technologies for rapid identification of microbes demonstrate a shift from traditional biochemical and molecular testing algorithms toward methods using mass spectrometry (MS) for the semiquantitative analysis of microbial proteins and genetic elements. This study was performed to assess the diagnos...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.161968
更新日期:2011-07-01 00:00:00
abstract::A method is described for separating antibody-bound from free fractions in ligand assays by column affinity chromatography, and its application to radioimmunoassay of choriomammotropin. In the method, 70 x 10 mm (i.d.) polypropylene columns containing about 150 mg of immunosorbent (goat anti-rabbit gamma-globulins cov...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-06-01 00:00:00
abstract:BACKGROUND:Quantification of 5-hydroxyindole-3-acetic acid (5-HIAA) in urine is useful in diagnosing and monitoring of patients with carcinoid tumors and in the study of serotonin (5-hydroxytryptamine) metabolism in various disorders. We describe an automated method that incorporates on-line solid-phase extraction (SPE...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.050062
更新日期:2005-09-01 00:00:00