Abstract：
BACKGROUND:Immunoassays specific for 1-84 parathyroid hormone (PTH) reportedly reflect the bioactivity of PTH; however, PTH immunoassays can be susceptible to interference by cross-reacting PTH fragments. In addition, these assays currently lack standardization. A methodology using immunocapture purification with liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection, along with a stable isotope-labeled internal standard, may help address these issues.
METHODS:We isolated 1-84 PTH from 1 mL serum by immunocapture on a 6.5-mm polystyrene bead. The immobilized PTH was digested in situ and analyzed by LC-MS/MS. For quantification, we used the selected reaction monitoring response from the N-terminal tryptic peptide 1-13 PTH ((1)SVSEIQLMHNLGK(13)).
RESULTS:The linear range of the assay was 39.1-4560 ng/L, and the limit of detection and limit of quantification were 14.5 ng/L and 39.1 ng/L, respectively. The intraassay CVs ranged from 6% to 11%, and the interassay CVs ranged from 7% to 17%. Interference by PTH fragments 1-44 PTH, 7-84 PTH, 43-68 PTH, 52-84 PTH, 64-84 PTH, and PTH-related protein (PTHrP) was journal_name journal_title authors doi subject pub_date pages issue eissn issn pii journal_volume pub_type
abstract：:The method is based on the selective activating capacity of dithiothreitol on creatine kinase isoenzyme MB, after isoenzyme MM is activated by glutathione. Isolated isoenzymes MM and MB of human and canine origin were assayed individually and in mixtures of known activities. When glutathione was present in the assay m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-10-01 00:00:00
abstract：:Creatine kinase isoenzyme BB (CK-BB) is found in the serum of patients with various types of cancer. Using both radioimmunoassay and agarose electrophoresis, we found abnormal amounts of this isoenzyme in the serum of 15 of 17 patients with untreated prostatic carcinoma. Among patients with other types of adenocarcino...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-08-01 00:00:00
abstract：:We assessed several methods of inorganic phosphate assay for their suitability in estimating phospholipids in digested extracts of amniotic fluids. The extraction and digestion procedures used for phospholipids from amniotic fluid were also examined critically. The effect of contamination by blood or obstetric cream h...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-09-01 00:00:00
abstract：BACKGROUND:The determination of cellular beta-galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell-based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for beta-ga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.115873
更新日期：2009-03-01 00:00:00
abstract：:We produced and characterized several monoclonal antibodies directed toward human plasma apolipoprotein A-I. Two of them, A-I-12 and A-I-57, individually precipitated purified or native high-density lipoprotein in agarose gel by double immunodiffusion. Because radial immunodiffusion performed with a single monoclonal ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-12-01 00:00:00
abstract：BACKGROUND:We evaluated the completeness of reporting of diagnostic test accuracy (DTA) systematic reviews using the recently developed Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA)-DTA guidelines. METHODS:MEDLINE® was searched for DTA systematic reviews published October 2017 to January 2...
journal_title：Clinical chemistry
pub_type： 杂志文章,meta分析
doi：10.1373/clinchem.2018.292987
更新日期：2019-02-01 00:00:00
abstract：:A reaction of urea, o-phthalaldehyde and N-(1-naphthyl)ethylenediamine is described for measurement of urea by manual, continuous-flow, and kinetic methods. The continuous-flow system requires 25 mu-l of sample; 40 samples can be analyzed per hour. The kinetic method requires no enzymes, has no lag phase, and has good...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-07-01 00:00:00
abstract：:We describe the interlaboratory testing of a candidate Reference Method (Part I) for uric acid in serum. The method is based on the ultrasound spectrophotometric quantitation of uric acid before and after incubation with uricase. A comprehensive investigation involving 12 laboratories was organized to document the tra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-02-01 00:00:00
abstract：BACKGROUND:Measurement of serum thyroglobulin (Tg) is used to monitor patients after treatment for differentiated thyroid carcinoma (TC). Difficulty in using Tg as a biomarker of the recurrence of TC in many patients stems from the presence of endogenous anti-Tg autoantibodies (Tg-AAbs), which can interfere with immuno...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2012.195594
更新日期：2013-06-01 00:00:00
abstract：:o-Phthaldialdehdye reagent was used in assaying urea with a miniature centrifugal analyzer. Seventeen samples can be assayed kinetically in 2 min at a current cost of less than a penny per test. The reaction is initiated in the instrument upon simultaneous mixing of the o-phthaldialdehyde reagent containing 10 microli...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-12-01 00:00:00
abstract：:We describe a homogeneous substrate-labeled fluorescent immunoassay for human IgM. In this competitive-binding method we use a fluorogenic substrate for Escherichia coli beta-galactosidase, N-(6-aminohexyl)-7-beta-galactosyl-coumarin-3-carboxamide, which is covalently coupled to IgM. The fluorescence emission intensit...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-05-01 00:00:00
abstract：:Owing to increased enzymatic hydrolysis of glutamine, additional ammonia is formed in blood and plasma specimens with increased gamma-glutamyltransferase activity (gamma-GT, EC 2.3.2.2.). The close correlation between gamma-GT and glutaminase (EC 3.5.1.2) activities (r = 0.97) in plasma, the inhibition with 6-diazo-5-...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-08-01 00:00:00
abstract：BACKGROUND:We evaluated the analytical performance of 4 cystatin C assays (Siemens N Latex on BNII, Roche Tina-quant on Cobas c501, Genzyme on Cobas c501, and Tosoh ST AIA-PACK on Tosoh AIA-600II) according to guidelines published by the Clinical and Laboratory Standards Institute. METHODS:We evaluated total imprecisi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.141531
更新日期：2010-08-01 00:00:00
abstract：:Human myocardial creatine kinase isoenzyme MM is present as a single form in tissue, but upon its release into plasma two additional forms, with faster anodal migration, are apparent on polyacrylamide electrophoresis. We designate the three forms as MM3, MM2, and MM1 in increasing order of anodal mobility. When tissue...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
abstract：:We developed a fluorometric method for determining delta-aminolevulinic acid (ALA) in urine of lead workers. A high-performance liquid chromatograph (HPLC) equipped with a fluorescence HPLC monitor is used. The detection limit for aqueous ALA is 20 micrograms/L (15 pmol of ALA in the 100-microL sample). The working li...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-09-01 00:00:00
abstract：:Pairs of values for serum triiodothyronine and serum triiodothyronine binding capacity were represented as maps of points for euthyroid populations (including subjects who were pregnant or were receiving estrogens) in the age groups 18-50, 51-64, 65-79, and greater than 80 years (504 subjects) and thyrotoxic populatio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-10-01 00:00:00
abstract：:We describe the process of certification for a gamma-glutamyltransferase reference material (CRM no. 319). Fifteen laboratories participated to this interlaboratory evaluation. All steps of the measurements were controlled in an effort to locate potential sources of variations. In particular, the exclusion of some dat...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-11-01 00:00:00
abstract：:A new enzymic method is described for the determination of creatine in urine by continuous-flow analysis. The measurement is accomplished by transforming creatine to formaldehyde in reactions catalyzed by creatinase (creatine amidinohydrolase) and sarcosine dehydrogenase. The formaldehyde is reacted with 4-amino-3-hyd...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-11-01 00:00:00
abstract：BACKGROUND:There is extended urinary excretion of Δ(9)-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH) in abstinent frequent cannabis smokers. We characterized THC, 11-OH-THC, THCCOOH, cannabidiol, cannabinol, THC-glucuronide, and THCCOOH-glucuronide disposition in urine of fr...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2013.214106
更新日期：2014-02-01 00:00:00
abstract：BACKGROUND:Genotyping methods that reveal single-nucleotide differences are useful for a wide range of applications. We used digestion of 3-way DNA junctions in a novel technology, OneCutEventAmplificatioN (OCEAN) that allows sequence-specific signal generation and amplification. We combined OCEAN with peptide-nucleic-...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.068817
更新日期：2006-10-01 00:00:00
abstract：BACKGROUND:Proteomic technology permits the investigation of genetic metabolic diseases at the level of protein expression. Changes in the expression, polypeptide structure, and posttranslational modification of individual proteins can be detected in complex mixtures of proteins. METHODS:We used high-resolution two-di...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
abstract：:Investigating the feasibility and validity of determining plasma ferritin concentration in blood obtained by finger prick, we studied 29 adults (ages 21-49 years) and 35 children (ages 14-66 months). Blood was sampled simultaneously in the same subject from both the antecubital vein (venous blood) and by finger pricki...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-05-01 00:00:00
abstract：:We used flameless atomic absorption spectrophotometry to measure concentrations of Fe, Mo, Li, As, and Zn in cerebrospinal fluid (CSF) of patients with malignant brain tumors benign brain tumors, non-brain malignant tumors and control (non-neoplastic disease) patients. Mean (and SD) concentrations (microgram/L) of the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-12-01 00:00:00
abstract：:We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile aci...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-02-01 00:00:00
abstract：:Genetic engineering of beta-galactosidase (EC 3.2.1.23) has led to the development of a new homogeneous assay system, CEDIA. The Z gene of the lac operon of Escherichia coli encodes a large enzymatically inactive polypeptide that spontaneously aggregates and folds to form active beta-galactosidase. Using recombinant D...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-09-01 00:00:00
abstract：:The clinical utilities of the emerging biochemical markers for mammary adenocarcinoma CA 15-3, CA 549, CA M26, CA M29, and MCA (mucin-like carcinoma-associated antigen) were assessed by a formal rating according to six desirable marker characteristics. All five indicators similarly have good specificities but limited ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1993-11-01 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：BACKGROUND:Microalbuminuria (MA) is recognized as an important risk factor for cardiovascular and renal complications in diabetes. We sought to evaluate how screening for MA is conducted and how urine albumin (UA) results are interpreted in primary care internationally. METHODS:General practitioners (GPs) received a c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.100917
更新日期：2008-10-01 00:00:00
abstract：BACKGROUND:Several plasma proteins have been suggested as markers for a variety of cardiovascular conditions but fail to qualify in independent patient cohorts. This may relate to interference of medication on plasma protein concentrations. We used proteomics to identify plasma proteins that changed in concentration wi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2017.282665
更新日期：2018-10-01 00:00:00
abstract：BACKGROUND:Simple, reproducible assays are needed for the quantification of sphingolipids, ceramide (Cer), and sphingoid bases. We developed an HPLC method for simultaneous quantification of total plasma concentrations of Cer, glucosylceramide (GlcCer), and ceramide trihexoside (CTH). METHODS:After addition of sphinga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.079012
更新日期：2007-04-01 00:00:00
