Abstract：
BACKGROUND:Absolute plasma hepcidin concentrations measured by various procedures differ substantially, complicating interpretation of results and rendering reference intervals method dependent. We investigated the degree of equivalence achievable by harmonization and the identification of a commutable secondary reference material to accomplish this goal. METHODS:We applied technical procedures to achieve harmonization developed by the Consortium for Harmonization of Clinical Laboratory Results. Eleven plasma hepcidin measurement procedures (5 mass spectrometry based and 6 immunochemical based) quantified native individual plasma samples (n = 32) and native plasma pools (n = 8) to assess analytical performance and current and achievable equivalence. In addition, 8 types of candidate reference materials (3 concentrations each, n = 24) were assessed for their suitability, most notably in terms of commutability, to serve as secondary reference material. RESULTS:Absolute hepcidin values and reproducibility (intrameasurement procedure CVs 2.9%-8.7%) differed substantially between measurement procedures, but all were linear and correlated well. The current equivalence (intermeasurement procedure CV 28.6%) between the methods was mainly attributable to differences in calibration and could thus be improved by harmonization with a common calibrator. Linear regression analysis and standardized residuals showed that a candidate reference material consisting of native lyophilized plasma with cryolyoprotectant was commutable for all measurement procedures. Mathematically simulated harmonization with this calibrator resulted in a maximum achievable equivalence of 7.7%. CONCLUSIONS:The secondary reference material identified in this study has the potential to substantially improve equivalence between hepcidin measurement procedures and contributes to the establishment of a traceability chain that will ultimately allow standardization of hepcidin measurement results.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
van der Vorm LN,Hendriks JC,Laarakkers CM,Klaver S,Armitage AE,Bamberg A,Geurts-Moespot AJ,Girelli D,Herkert M,Itkonen O,Konrad RJ,Tomosugi N,Westerman M,Bansal SS,Campostrini N,Drakesmith H,Fillet M,Olbina G,Pasrichadoi
10.1373/clinchem.2016.256768subject
Has Abstractpub_date
2016-07-01 00:00:00pages
993-1001issue
7eissn
0009-9147issn
1530-8561pii
clinchem.2016.256768journal_volume
62pub_type
杂志文章abstract：:We describe a new multilayer immunoassay element for the determination of haptens in undiluted serum and plasma. Polysaccharide layers are coated onto a plastic base. The signal layer contains an immobilized antibody and a fluorescent-labeled hapten. A second layer, containing a pigment, acts as an optical screen. Sam...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
abstract：:We report a procedure for determining fecal long-chain fatty acids (LCFA), triglycerides, and cholesterol after detergent extraction with 10 mL/L Triton X-100, 6 mL/L Brij 30, and 0.1 mol/L HCl in isotonic saline by enzymatic analysis of the extraction supernates. Mean recoveries of calibrators ranged from 105% to 117...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-12-01 00:00:00
abstract：:We describe the case of a three-year-old girl with Wilms' tumor, whose serum showed at least a fivefold increase in relative viscosity although concentrations of albumin and immunoglobulins were normal. An unusual electrophoretogram of serum protein prompted further investigation. The increased viscosity was caused by...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-06-01 00:00:00
abstract：:A triclonal gammopathy is an immunoglobulin abnormality in which three discrete monoclonal subpopulations of immunoglobulin molecules are present in a patient's serum. Monoclonal and biclonal gammopathies have been studied extensively, but relatively little is known about the much rarer triclonal gammopathies. The cas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：BACKGROUND:Commercial immunoassays for testosterone (Te) may give inaccurate results for samples from women and children, leading to misdiagnosis and inappropriate treatment. We developed a sensitive and specific tandem mass spectrometric assay for measurement of Te at the concentrations encountered in women and childr...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.052167
更新日期：2006-01-01 00:00:00
abstract：:We adapted an inhibition assay for methotrexate, involving dihydrofolate reductase from bovine liver, for use with a discrete analyzer (the ABA-100). The analyzer was used both for dilution and a 5-min pre-incubation of the sample with NADPH--enzyme reagent, and for the assay itself. The standard curve was linear betw...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-02-01 00:00:00
abstract：:A convenient screening procedure for presence of drugs of abuse in urine consists of two steps: adsorption of the drugs from urine onto a paper loaded with cation-exchange resin and detection of the adsorbed drugs by direct radioimmunoassay. The first step can be performed in the field, the second in a central laborat...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-10-01 00:00:00
abstract：:We compared three current methods (immunoinhibition, "Isomune-CK" immunoprecipitation, and the Tandem-E CKMB II immunoenzymometric assay) for determination of creatine kinase (CK; EC 2.7.3.2) isoenzyme MB in serum. Although results inter-correlated well, the immunoinhibition assay gave higher activity values. Atypical...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：BACKGROUND:The fibroblast growth factor (FGF) and FGF receptor (FGFR) axis plays a critical role in tumorigenesis, but little is known of its influence in ovarian cancer. We sought to determine the association of genetic variants in the FGF pathway with risk, therapeutic response, and survival of patients with ovarian ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.211490
更新日期：2014-01-01 00:00:00
abstract：:We studied the association between gamma-glutamyltransferase (GGT) and apolipoproteins A or B in serum of 42 patients with various hepatobiliary diseases. Binding of the enzyme to apolipoprotein A is not related to a clearly defined disease, but appears to be mainly influenced by the ratio of total cholesterol to GGT ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-08-01 00:00:00
abstract：:We evaluated a new, simple, enzymatic kinetic method from Wako Chemicals GmbH in comparison with a kinetic Jaffé method by using isotope dilution-mass spectrometry (ID-MS) as a reference method. An ID-MS-calibrated serum standard was used. Both the enzymatic and the Jaffé method correlated well with ID-MS, except for ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
abstract：BACKGROUND:The coexistence of hypertension and dyslipidemia synergistically increases the risk of cardiovascular events. We investigated the effect of the lipid-lowering agent micronized fenofibrate on inhibition of carotid atherosclerosis in patients with essential hypertension and mild hyperlipidemia. METHODS:We mea...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
doi：10.1373/clinchem.2006.074724
更新日期：2006-11-01 00:00:00
abstract：:A high (2.0 mol/L) NaCl concentration apparently suppresses the secondary-site binding of bilirubin by human serum albumin. Thus if an excess of bilirubin is added to human serum albumin or to neonatal serum in buffer containing 0.1 mol of tris(hydroxymethyl)aminomethane and 2.0 mol of NaCl per liter (pH 7.5), and the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-01-01 00:00:00
abstract：:Biological variation is inherent in all medical tests and is a major source of error in clinical test interpretation. We use inherent test error due to biological variability as the touchstone by which to validate the clinical acceptability of analytical goals. Analytical goals should consist of sets of complementary ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1993-07-01 00:00:00
abstract：:Assays with different specificity are used for cyclosporin monitoring in clinical transplantation. A recent survey of 35 centers showed that 86% used immunoassays for cyclosporin A (CsA). In consensus documents the following performance criteria were recommended: (a) imprecision < or = 10% at 50 microg/L and < or = 5%...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-10-01 00:00:00
abstract：:In considering factors that might influence measurement of free thyroxin (T4), we evaluated the proportion (%) of T4 that could be stripped from thyroxin-binding globulin (TBG). The percentage of free T4 was measured in serially diluted sera from four normal subjects, four patients with hyperthyroidism or hypothyroidi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-02-01 00:00:00
abstract：BACKGROUND:Soluble CD146 (sCD146), is an endothelial marker with similar diagnostic power as natriuretic peptides in decompensated heart failure (HF). While natriuretic peptides are released by the failing heart, sCD146 may be released by veins in response to stretch induced by systemic congestion in HF. This study inv...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2016.260471
更新日期：2017-01-01 00:00:00
abstract：BACKGROUND:Although numerous lateral flow immunoassays (LFIAs) have been developed and widely used, inadequate analytical sensitivity and the lack of multiple protein detection applications have limited their clinical utility. We developed a new LFIA device for the simultaneous detection of high-sensitivity cardiac tro...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.171694
更新日期：2011-12-01 00:00:00
abstract：:The IFCC-recommended procedure for aspartate aminotransferase (EC 2.6.1.1) was adapted to the centrifugal analyzer and evaluated during five years. The main hindrance to widespread use of the recommended method is the need for pre-incubation with pyridoxal phosphate. The present method includes a 10-min pre-incubation...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-01-01 00:00:00
abstract：:I describe the automation/mechanization of several areas of sample processing at SmithKline Beecham Clinical Laboratories. By analyzing and implementing new systems for conveyance and sorting of incoming specimens, specimen processing, within-laboratory specimen delivery, specimen storage and retrieval, and client res...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-09-01 00:00:00
abstract：:The cytokine rumor necrosis factor-alpha (TNF-alpha) plays a prominent role in the inflammatory response and has been quantified in several kinds of body fluids. A safe method for keeping samples under the best storage conditions for later studies is clearly needed. We estimated TNF-alpha shelf life by using an accele...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-05-01 00:00:00
abstract：BACKGROUND:A sensitive gas chromatography-negative ion chemical ionization mass spectrometry (GC/MS-NICI) method was developed and validated for the measurement of Delta(9)-tetrahydrocannabinol (THC) in human sweat patches. METHODS:THC-d(0) and THC-d(3) were added to worn blank sweat patches (PharmChek; PharmChem Inco...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2004.034868
更新日期：2004-11-01 00:00:00
abstract：BACKGROUND:Meconium analysis is a diagnostically sensitive and objective alternative to maternal self-report for detecting prenatal tobacco exposure. Nicotine and metabolite disposition in meconium is poorly characterized, and correlation of analytes' concentrations with neonatal outcomes is unexplored. Our objectives ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.109173
更新日期：2008-12-01 00:00:00
abstract：:Methods are described for detection of lactate dehydrogenase (LDH) inhibitors in preparations of reduced nicotinamide adenine dinucleotide. They are (a) comparison of values by kinetic methods with those measured for highly purified NADH and (b) examination of Lineweaver-Burk plots. Chromatographic inhomogeneities are...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-10-01 00:00:00
abstract：:With the ultramicroanalytical system described here we can measure glucose in 1 microL of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops. The reflectance of these spots is measured with a reflectance digital matrix photome...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
abstract：:We describe the measurement of human immunoglobulins IgG, IgA, and IgM in diluted sera, with diluted commercial monospecific antisera, with use of a 36-place centrifugal analyzer (RotoChem IIa; American Instrument Co., Silver Spring, MD 20920). The assay involves a two-point kinetic turbidimetric technique. The change...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-04-01 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：:This simple, accurate, and reproducible colorimetric method for determining the activity of angiotensin-I converting enzyme is based upon colorimetry of the quinoneimine dye produced from the substrate p-hydroxyhippuryl-L-histidyl-L-leucine by action of this enzyme through the following series of reactions. The enzyme...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-11-01 00:00:00
abstract：BACKGROUND:We explored the utility of multiplexed temperature gradient capillary electrophoresis (TGCE) as a screening tool for identifying genetic changes in the human mitochondrial genome. We examined changes in mitochondrial DNA (mtDNA) in nonmelanoma skin cancers (NMSCs), using TGCE to resolve genetic differences c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.040311
更新日期：2005-02-01 00:00:00
abstract：:Gel filtration of serum by use of dextran bisacrylamide beads ("Sephacryl S-200," fractionation range: 5000-250 000 daltons), separates the serum proteins into three distinct peaks. We used an eluent containing (per liter) 140 mmol of sodium, 1.10 mmol of calcium, 0.50 mmol of magnesium, and 10 mmol of 2-([2-hydroxy-1...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-12-01 00:00:00
