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:BACKGROUND:In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a comprehensive general unknown screening method based on liquid chromatography coupled with a hybrid triple-quadrupole linear ion trap mass spectrometer. MET...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.067116
更新日期:2006-09-01 00:00:00
abstract::We can detect the beta-globin gene sickle cell mutation by using an assay based on the ligase chain reaction. The simultaneous amplification of the human growth hormone gene in the same reaction serves as a control for the amount of template DNA or amplification efficiency. Ligation products, which are biotinylated at...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-01-01 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:BACKGROUND:An association has been described between mortality in children with meningococcal disease and functional polymorphisms in the interleukin-1 (IL1) cluster. We undertook a multicenter study to evaluate associations of these polymorphisms in a Central European population. PATIENTS AND METHODS:The study involv...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2005.058537
更新日期:2006-03-01 00:00:00
abstract::We studied the specificity of kinetic methods of analysis, with emphasis on creatinine determination. The error contributed by an interferent that reacts with the analytical reagent and absorbs at the wavelength of analysis is shown to be related to the ratio of the equilibrium absorbances of the analyte and interfere...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-04-01 00:00:00
abstract::We measured thyroid hormones and thyroxin-binding proteins in serum from 62 normal lactating and 52 nonlactating women at three months postpartum, and compared these values with those for 42 nonpregnant control women of similar age. Mean thyroxin concentrations in the lactating and nonlactating women were significantl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract::The characteristics of the Abbott selective fluorescence polarization immunoassay for cyclosporine in whole blood (TDXSP) were compared with the Incstar radioimmunoassay by using kit standards (INCSP) or TDXSP standards (INCTDX) with samples from adult (48) and pediatric (24) liver-transplant recipients and a further ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-01-01 00:00:00
abstract::For many lysosomal storage disorders, presymptomatic detection, before the onset of irreversible pathology, will greatly improve the efficacy of current and proposed therapies. In the absence of a family history, presymptomatic detection can be achieved only by a comprehensive newborn screening program. Recently we re...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-10-01 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 developed a novel noncompetitive immunoassay format for monoepitopic analytes and describe here a model assay for triiodothyronine (T3), performed on Ciba Corning's ACS:180 analyzer. Acridinium ester (AE)-labeled bivalent anti-T3 was incubated with the sample, producing AE-anti-T3/T3 complexes and unreacted AE-anti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-07-01 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::For 51 liver allograft recipients, we evaluated whether serum profiles of delta (Bd) and conjugated bilirubins (Bc) could be used to diagnose rejection during the first 30-50 postoperative days, in comparison with histology as the "gold standard." Daily measurements of aspartate aminotransferase, alkaline phosphatase,...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 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:BACKGROUND:Growth differentiation factor 15 (GDF15), a stress-responsive cytokine produced in cardiovascular cells under conditions of inflammation and oxidative stress, is emerging as an important prognostic marker in individuals with and without existing cardiovascular disease (CVD). We therefore examined the clinica...
journal_title:Clinical chemistry
pub_type: 杂志文章,meta分析
doi:10.1373/clinchem.2012.190322
更新日期:2012-11-01 00:00:00
abstract::This article reviews key advances in ion-selective electrode technology that have made potentiometric measurements of ionized calcium (Ca2+) reliable and precise. Our use of two second-generation Ca2+ analyzers (Radiometer ICA1 and NOVA 8) made possible uninterrupted service as volume increased to 31 640 patient tests...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1986-08-01 00:00:00
abstract::We describe a chromatographic system involving a high-performance chemically-bonded reverse-phase column and fluorescence detection for measurement of indoles in urine. We controlled retention and selectivity by optimizing the methanol content and pH of the mobile phase. Six reference indoles were separated in less th...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-02-01 00:00:00
abstract::Creatine kinase (CK) isoenzymes MM, MB, and BB are located primarily in the cell cytosol, and increased CKMB in plasma is the hallmark of myocardial infarction. However, whether CK is released with reversible ischemic injury remains controversial. Here, we assessed plasma CK activity--cytosolic and mitochondrial CK--i...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-03-01 00:00:00
abstract:BACKGROUND:Paraoxonase may mitigate oxidative damage and thus lower risk of macrovascular disease. METHODS:DNA samples from 2252 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study were genotyped for the L55M and Q192R polymorphisms of the PON1 (paraoxonase 1) gene, and paraoxonase acti...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2007.099044
更新日期:2008-04-01 00:00:00
abstract:BACKGROUND:Institutions face increasing charges related to molecular genetic testing for neurological diseases. The literature contains little information on the utilization and performance of these tests. METHODS:A retrospective utilization review was performed to determine the diagnostic yield of neurogenetic tests ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.083360
更新日期:2007-06-01 00:00:00
abstract::Using 123 specimens, we compared the concordance of three different methods for determining glycohemoglobin (GHb): the Diamat (Bio-Rad Laboratories), an automated analyzer measuring HbA1c by cation-exchange chromatography; an assay with the IMx analyzer (Abbott Laboratories), based on boronate affinity binding; and an...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-02-01 00:00:00
abstract::I developed a standard procedure for assessing sensitivity, intra-assay precision, parallelism of sample dilutions, and assay drift, using a single trial assay kit. I used this to compare the performance of 10 commercial kits with an in-house radioimmunoassay for human thyrotropin. No one kit stood out as clearly supe...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-01-01 00:00:00
abstract::One currently observes many healthcare institutions rushing to reengineer and install information systems with the expectation of achieving enhanced efficiency, competitiveness, and, it is hoped, higher patient satisfaction resulting from timely, high-quality care. Unfortunately, information system concepts, design, a...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1995-09-01 00:00:00
abstract:BACKGROUND:Technological advances have resulted in a renaissance of proteomic studies directed at finding markers of disease progression, diagnosis, or responsiveness to therapy. Renal diseases are ideally suited for such research, given that urine is an easily accessible biofluid and its protein content is derived mai...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2011.165969
更新日期:2012-02-01 00:00:00
abstract:BACKGROUND:Identifying novel risk markers in cardiovascular patients remains a research priority. Longer follow-up generally is considered favorable in such studies, but associations of interest may become attenuated with increasing follow-up. This issue has not been adequately addressed in the context of patient cohor...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.263202
更新日期:2017-03-01 00:00:00
abstract::We modified a one-step, two-site, double monoclonal immunoenzymometric assay (Abbott Laboratories) for serum alpha1-fetoprotein (AFP) to increase its sensitivity and improve test precision at the low end. We increased sample size, incubation interval, and reaction time and temperature, and decreased the final reaction...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-04-01 00:00:00
abstract:BACKGROUND:The genotype of hepatitis C virus (HCV) is a predictor of antiviral therapeutic response. We describe an approach for HCV genotype determination by real-time PCR and melting curve analysis. METHODS:After automated nucleic acid extraction, we used reverse transcription-PCR in a block cycler to amplify nucleo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-12-01 00:00:00
abstract::We describe a rapid and simple insulin RIA in which proinsulin and conversion intermediates do not interfere. Three monoclonal antibodies (S1, S2, and S53) were selected for their specificity (directed, respectively, against the B10 region, the junction between A chain and C-peptide, and the junction between B chain a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-07-01 00:00:00
abstract::We have improved the protocol for RNA quantification by using RNase protection. Instead of precipitation and extraction with phenol and chloroform, we use a faster and more reliable precipitation based on guanidinium thiocyanate (GdSCN). The internal standard is produced by in vitro transcription of a DNA template con...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-11-01 00:00:00
abstract::Detection and characterization of small IgM paraproteins by immunoelectrophoresis are often difficult because of (a) slow diffusion of the macromolecular immunoglobulin, and (b) the obscuring of the light chain, especially kappa, by the light chains of background polyclonal immunoglobulin (the "umbrella effect"). Vari...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-08-01 00:00:00
abstract::We investigated the effects on plasma osteocalcin concentrations of different anticoagulants used to collect the blood samples. Plasma osteocalcin concentrations measured by enzyme immunoassay and radioimmunoassay are influenced by the nature of the anticoagulants used. The most significant difference between concentr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-02-01 00:00:00