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 DNA techniques, we have been able to engineer beta-galactosidase protein into a large polypeptide (an enzyme acceptor, EA) and a small polypeptide (an enzyme donor, ED). The EAs and EDs are both enzymatically inactive, but spontaneously associate to form enzymatically active tetramers. In the assay, hapten or analyte is attached to an ED, and an analyte-specific antibody is used to inhibit the spontaneous assembly of active enzyme. Analyte in a patient's serum competes with the analyte in the analyte-ED conjugate for antibody, modulating the amount of beta-galactosidase formed. The signal generated by enzyme substrates is directly proportional to the analyte concentrations in the patient's serum. We describe quick (5-15 min) colorimetric tests for digoxin, requiring no serum pretreatments or predilutions and suitable for use with centrifugal and random-access analyzers.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Henderson DR,Friedman SB,Harris JD,Manning WB,Zoccoli MAsubject
Has Abstractpub_date
1986-09-01 00:00:00pages
1637-41issue
9eissn
0009-9147issn
1530-8561journal_volume
32pub_type
杂志文章abstract：:A precolumn derivatization method was optimized for rapid and specific analysis of total urinary hydroxyproline by HPLC. After an overnight hydrolysis, urine samples dried and reconstituted with the internal standard cysteic acid (in sodium hydrogen carbonate, pH 9.3) were derivatized with N,N-diethyl-2,4-dinitro-5-fl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-03-01 00:00:00
abstract：BACKGROUND:alpha(1)-Antitrypsin is the major plasma serine protease inhibitor. Its deficiency is mainly associated with the alleles PI*S and PI*Z and can lead to obstructive lung disease in adults and to liver cirrhosis during childhood. METHODS:A multiplex PCR method has been established that uses two sets of primers...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-02-01 00:00:00
abstract：:This new one-step chemiluminescent immunoassay of free thyroxin (FT4) involving a thyroxin-immunoglobulin conjugate labeled with acridinium ester (Magic Lite System; Ciba Corning Diagnostics Corp., Medfield, MA) is rapid (one 1-h incubation), requires two calibrators per run, and takes 10 s per sample for the quantifi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
abstract：:Major depression is one of the most common clinical problems seen by primary-care physicians. The prevalence is 5% to 10% in primary-care outpatients and 15% in medically ill inpatients. Despite this high prevalence rate, depression is frequently not accurately diagnosed. Evidence suggests that misdiagnosis often occu...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1988-05-01 00:00:00
abstract：BACKGROUND:The recent interest of clinical laboratories in developing serum testosterone assays based on isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) stems from the lack of accuracy of direct immunoassays. In this study, we assessed the accuracy and state of standardization (traceabilit...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.105841
更新日期：2008-08-01 00:00:00
abstract：:We describe optimal conditions for immobilization of two monoclonal antibodies to progesterone for solid-phase assays. Polystyrene surfaces are refined with Protein A to achieve uniform, reproducible, stable, and sterically accessible immobilization of immunoglobulins (IgG). To this end, we optimized the amount of imm...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
abstract：:We studied the EMIT (Enzyme Multiplied Immunoassay Technique, Syva) procedures for the assay of phenytoin and phenobarbital in serum, adapting them to the miniature Centrifugal Fast Analyzer. For different concentrations of drug, each rate of reaction decreased continuously with time, tending to converge on a single c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-08-01 00:00:00
abstract：BACKGROUND:Although it is being increasingly applied, blood collection for drug testing in sport presents some logistic issues that complicate full applicability on a large scale. The use of dried blood spots (DBS) could benefit compliant blood testing considerably owing to its simplicity, minimal invasiveness, analyte...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.257592
更新日期：2016-10-01 00:00:00
abstract：BACKGROUND:Intraventricular hemorrhage (IVH) is a major cause of neurologic disabilities in preterm newborns. We evaluated the use of plasma activin A concentrations to predict the development of perinatal IVH. METHODS:We measured nucleated erythrocyte (NRBC) counts, plasma activin A, hypoxanthine (Hyp), and xanthine ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.065979
更新日期：2006-08-01 00:00:00
abstract：:Erythromycin, phenazopyridine, methenamine mandelate, acetazolamide, and ascorbic acid reportedly interfere with the Porter-Silber reaction in the determination of urinary 17-hydroxycorticosteroids. Sodium bisulfite, added to the urine after hydrolysis with glucuronidase, removed almost all nonsteroidal interferences ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-11-01 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：:Throughout the 1970s, controversy centered both on immunoassay "sensitivity" per se and on the relative sensitivities of labeled antibody (Ab) and labeled analyte methods. Our theoretical studies revealed that RIA sensitivities could be surpassed only by the use of very high-specificity nonisotopic labels in "noncompe...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1991-11-01 00:00:00
abstract：BACKGROUND:Although lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels are associated with cardiovascular events, Lp-PLA(2) is physically linked to LDL cholesterol (LDL-C). Whether measures of Lp-PLA(2) mass or activity continue to predict risk after LDL-C reduction by statin therapy is uncertain. METHODS:Lp...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.180281
更新日期：2012-05-01 00:00:00
abstract：:Comparison of two methods for determining a substance is a common procedure in clinical chemistry. Almost without exception, normal theory statistics are used with the tacit assumption that the data under test show gaussian distributions. Experience has led us to question this assumption for populations of differences...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
abstract：:The isoenzymes of lactate dehydrogenase (EC 1.1.1.27) were separated with excellent resolution in less than 1 h by high-pressure anion-exchange chromatography. These isoenzymes were determined in some tissue extracts and high-activity serum samples by this technique. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-04-01 00:00:00
abstract：:We describe a simple method in which a water-soluble mixture of triocatanoin and a surfactant, "Triton X-114," are used in preparing solutions of triglycerides (triacylglycerols) in either human serum, solutions of albumin, or water. Analytical recovery added triglyceride was quantitative by two methods. The addition ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-08-01 00:00:00
abstract：:Establishing associations between environmental agents and disease presents challenges to both epidemiologists and toxicologists, particularly in cases of complex gene-environment interactions and when there is a long latency between exposure and disease. Biologic markers, physiological signals that reflect exposure, ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1994-07-01 00:00:00
abstract：BACKGROUND:In malignancy, gene mutations frequently occur in tumor suppressor genes such as p53 and are sporadically located. We describe a homogeneous method for amplification and mutation scanning, and apply the method to the p53 gene. METHODS:Using a series of overlapping fluorescein-labeled oligonucleotides comple...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-08-01 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：:Measurement of serum ascorbate may be useful in long-term population studies because of the possible influence of ascorbate on numerous physiological factors. We describe an automated method for determining ascorbate in serum and urine by using the reduction of ferric iron by ascorbate and the formation of a color bet...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-09-01 00:00:00
abstract：:Determination of the MB isoenzyme of creatine kinase in patients with acute myocardial infarction may be disturbed by the presence of macro creatine kinase. The relative molecular mass of this form of creatine kinase in human serum is at least threefold that of the ordinary enzyme, and it is more thermostable. Here we...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：BACKGROUND:Reliable detection of neuroblastoma cells in bone marrow (BM) is critical because BM involvement influences staging, risk assessment, and evaluation of therapeutic response in neuroblastoma patients. Standard cytomorphologic examination of BM aspirates is sensitive enough to detect single tumor cells. Conseq...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.059485
更新日期：2006-03-01 00:00:00
abstract：BACKGROUND:Pompe disease (PD) is the first lysosomal storage disorder to be added to the Recommended Uniform Screening Panel for newborn screening. This condition has a broad phenotypic spectrum, ranging from an infantile form (IOPD), with severe morbidity and mortality in infancy, to a late-onset form (LOPD) with vari...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.259036
更新日期：2017-04-01 00:00:00
abstract：:Intra- and interindividual components of biological variation have been determined for total thyroxin (TT4), free thyroxin (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyrotropin (TSH). Calculated analytical goals (CV, %) for the precision required for optimal patient care are: TT4 less than ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-06-01 00:00:00
abstract：:Circulating prostate cells can be detected in cancer patients by using reverse transcriptase-PCR (RT-PCR) assay for prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSM) mRNA. A quality-control study involving a conventional RT-PCR assay was performed and, surprisingly, detected both transcripts...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
abstract：:To validate azotemic markers as an index for intradialytic changes in solute concentration, we compared eight solutes (pseudouridine, xanthine, hypoxanthine, peak 4, peak 5, p-hydroxyhippuric acid, indoxyl sulfate, and hippuric acid) with five classical azotemic markers (urea, creatinine, uric acid, phosphate, and pot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：BACKGROUND:In recent years, there have been significant advances in the development of enzyme replacement and other therapies for lysosomal storage disorders (LSDs). Early diagnosis, before the onset of irreversible pathology, has been demonstrated to be critical for maximum efficacy of current and proposed therapies. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-09-01 00:00:00
abstract：:We have developed a fully enzymatic method to measure 1,5 anhydro-D-glucitol (1,5-AG) in serum through use of pyranose oxidase (PROD: EC 1.1.3.10), glucokinase (EC 2.7.1.2), and an ATP-regenerating system. In a previous report (Clin Chem 1989;35:2039-43) the glucose interfering with the measurement of 1,5-AG was remov...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-11-01 00:00:00
abstract：:A method for determining platinum in biological materials by flameless atomic absorption spectrometry has been developed for use in pharmacological studies of platinum antitumor compounds. Tissue digests are analyzed in a heated graphite atomizer, with use of background correction and ramp temperature charring. We hav...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-07-01 00:00:00
abstract：BACKGROUND:Insulin, growth hormone (GH), and growth factors (insulin-like growth factors [IGFs] and their binding proteins [IGFBPs]) are known to influence fetal growth and also the synthesis/secretion of the recently discovered hormones leptin and ghrelin. METHODS:In 153 delivering mothers and their offspring at birt...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.095299
更新日期：2008-03-01 00:00:00
