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 "noncompetitive" designs, preferably with monoclonal antibodies. The time-resolved fluorescence methodology known as DELFIA--developed in collaboration with LKB/Wallac--represented the first commercial "ultrasensitive" nonisotopic technique based on these theoretical insights, the same concepts being subsequently adopted in comparable methodologies relying on the use of chemiluminescent and enzyme labels. However, high-specific-activity labels also permit the development of "multianalyte" immunoassay systems combining ultrasensitivity with the simultaneous measurement of tens, hundreds, or thousands of analytes in a small biological sample. This possibility relies on simple, albeit hitherto-unexploited, physicochemical concepts. The first is that all immunoassays rely on the measurement of Ab occupancy by analyte. The second is that, provided the Ab concentration used is "vanishingly small," fractional Ab occupancy is independent of both Ab concentration and sample volume. This leads to the notion of "ratiometric" immunoassay, involving measurement of the ratio of signals (e.g., fluorescent signals) emitted by two labeled Abs, the first (a "sensor" Ab) deposited as a microspot on a solid support, the second (a "developing" Ab) directed against either occupied or unoccupied binding sites of the sensor Ab. Our preliminary studies of this approach have relied on a dual-channel scanning-laser confocal microscope, permitting microspots of area 100 microns 2 or less to be analyzed, and implying that an array of 10(6) Ab-containing microspots, each directed against a different analyte, could, in principle, be accommodated on an area of 1 cm2. Although measurement of such analyte numbers is unlikely ever to be required, the ability to analyze biological fluids for a wide spectrum of analystes is likely to transform immunodiagnostics in the next decade.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Ekins RP,Chu FWsubject
Has Abstractpub_date
1991-11-01 00:00:00pages
1955-67issue
11eissn
0009-9147issn
1530-8561journal_volume
37pub_type
杂志文章,评审abstract::We determined the LD-1/LD-2 isoenzyme ratio in hemolysates of erythrocytes by electrophoresis on cellulose acetate and on agarose. A ratio exceeding 1.0 was found with the former but not the latter. Results were similar for in vitro models of hemolytic disorders. Using cellulose acetate electrophoresis, we determined ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-08-01 00:00:00
abstract:BACKGROUND:Little is known about trace metal alterations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentrations of trace elements. Because these patients are at risk for alterations of trace elements as well as for ...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:
更新日期:1999-09-01 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::The use of 4-chlorotestosterone acetate by farmers for cattle fattening was recently demonstrated although the use of this anabolic steroid is strictly forbidden in the European Union. We investigated the metabolism of 4-chlorotestosterone acetate in the bovine species after intramuscular and oral administration. Nine...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-05-01 00:00:00
abstract:BACKGROUND:The alteration of the bone microenvironment as a consequence of skeletal metastases is poorly understood. The aim of this study was to search for patterns of bone markers in relation to primary tumor type, bone pain, and number of sites involved in patients with bone metastases. METHODS:We studied 323 patie...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract:BACKGROUND:Previous studies have shown a single linear relationship between mean plasma glucose (MPG) and hemoglobin A(1c) (HbA(1c)). We examined the relationship in different treatment groups of patients with type 1 diabetes participating in the Diabetes Control and Complications Trial (DCCT). METHODS:Seven-point glu...
journal_title:Clinical chemistry
pub_type: 杂志文章,随机对照试验
doi:10.1373/clinchem.2006.079756
更新日期:2007-05-01 00:00:00
abstract::Investigating the interference of danazol in testosterone radioimmunoassays, we measured serum testosterone concentrations in the serum of women receiving danazol, with three testosterone radioimmunoassay kits. All of these showed positive interference by danazol or its metabolites (or both). Values for testosterone o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-01-01 00:00:00
abstract::We evaluated the enzymic mechanism by which 3-keto butylidene-beta-2-chloro-4-nitrophenyl maltopentaoside (3KB-G5-CNP) serves as a substrate for serum pancreatic (p-) and salivary (s-) amylases. In aliquots of the reaction mixture, three kinds of beta-2-chloro-4-nitrophenyl oligosaccharides (glucose, maltoside, and ma...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-08-01 00:00:00
abstract::We evaluated the HemoCue beta-Glucose Photometer system for use in our neonatal intensive care unit by assaying 178 heparinized whole-blood samples obtained by heel stick. The required sample size is 5 microL. Plasma glucose was analysed by a glucose oxidase/oxygen electrode methodology. Across the glucose range of 1....
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-11-01 00:00:00
abstract:BACKGROUND:Although microRNAs (miRNAs) play essential roles in spermatogenesis, little is known about seminal plasma miRNAs in infertile men. We investigated the profile of seminal plasma miRNAs in infertile men to identify miRNAs that are altered in infertility; we then evaluated their diagnostic value. METHODS:Semin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.169714
更新日期:2011-12-01 00:00:00
abstract:BACKGROUND:Group B streptococcal infections are the leading cause of sepsis and meningitis in newborns. A rapid and reliable method for the detection of this pathogen at the time of delivery is needed for the early treatment of neonates. Isothermal amplification techniques such as recombinase polymerase amplification h...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.213504
更新日期:2014-04-01 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:BACKGROUND:Quantification of integrated proviral HIV DNA by repetitive-sampling Alu-HIV PCR is a candidate virological tool to monitor the HIV reservoir in patients. However, the experimental procedures and data analysis of the assay are complex and hinder its widespread use. Here, we provide an improved and simplified...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.219378
更新日期:2014-06-01 00:00:00
abstract:BACKGROUND:We describe a simple tetra-primer amplification refractory mutation system PCR (T-ARMS-PCR) for detecting MUTYH mutations, which are associated with colorectal adenomas and colorectal cancer. METHODS:We designed specific T-ARMS-PCR assays for 6 mutations (Y165C, G382D, 1395_7delGGA, Y90X, 1103delC, and R231...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.060137
更新日期:2006-04-01 00:00:00
abstract::Serum specimens from patients on primidone therapy were assayed by two currently available procedures: a commercially available enzyme immunoassay (EMIT) and a published gas-chromatographic procedure. Both procedures were done with commercially available materials and equipment. Results by the two procedures agreed we...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-06-01 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 have designed a re-usable dialysis cell and a complex dialysis buffer, with which undiluted serum samples can be dialyzed with minimal changes in their serum matrix. Dialysate thyroxin (free T4) is then measured by a sensitive RIA for T4. The range of reportability was 2-128 ng/L, the normal range was 8-27 ng/L, an...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-09-01 00:00:00
abstract::We compared the performance of three methods for quantifying high-density lipoprotein cholesterol (HDL-C) with the Reference Method for HDL-C, using samples with a wide range of triglyceride (TG) concentrations (290-18000 mg/L). All three comparison assays-- utilizing a magnetic dextran sulfate precipitating reagent, ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-05-01 00:00:00
abstract::Mesenteric vascular occlusion and intestinal obstruction are difficult-to-diagnose medical emergencies. We evaluated a large panel of biochemical markers as diagnostic and prognostic indicators in a rat model of intestinal infarction and partial, complete, and strangulated intestinal obstruction. After intestinal infa...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-02-01 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:BACKGROUND:At concentrations <500 microg/L, serum alpha-fetoprotein (AFP) has low specificity in the diagnosis of hepatocellular carcinoma (HCC), but monosialylated AFP (msAFP) is more specific for HCC. We describe two strategies for quantitative analysis of msAFP and explore their diagnostic accuracy in cases of HCC w...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-07-01 00:00:00
abstract::In the disposable rotor of the SAM microcentrifugal analyzer, various lyophilized reagents are predistributed in 24 33-microL cuvets, for determination of multiple analytes in one specimen (e.g., for patient profiles). We evaluated a prototype of this system, which can be used at 25, 30, or 37 degrees C; absorbance re...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-09-01 00:00:00
abstract::We evaluated a new EMIT II monoclonal amphetamine/methamphetamine assay for screening human urine by comparing it with the EMIT d.a.u. monoclonal amphetamine/methamphetamine assay and a fluorescence polarization assay. The EMIT II assay has a cutoff of 1 mg/L d-methamphetamine. The EMIT II and EMIT d.a.u. assays were ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-01-01 00:00:00
abstract::We describe a single-cuvette enzyme-linked immunosorbent assay (ELISA) based on enzymic rate kinetics. This kinetic assay can yield linear quantitative data on immunoglobin concentrations. Optimum assay conditions, component concentrations, reaction intervals, and pH are described. Assay linearity and sensitivity are ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-08-01 00:00:00
abstract:BACKGROUND:Sensitive and specific biomarkers for the early detection of esophageal squamous cell carcinoma (ESCC) are urgently needed to reduce the high morbidity and mortality of the disease. The discovery of serum microRNAs (miRNAs) and their unique concentration profiles in patients with various diseases makes them ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.147553
更新日期:2010-12-01 00:00:00
abstract::We report an easy, rapid method for quantifying bone isoenzyme of alkaline phosphatase (EC 3.1.3.1., ALP) in serum. The original method described by Rosalki and Ying Foo (Clin Chem 1984;30:1182-6) was somewhat simplified. In contrast to their results, we found that bone ALP is precipitated quantitatively by wheat-germ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-10-01 00:00:00
abstract:BACKGROUND:The ratio of plasma aldosterone concentration to plasma renin activity (PRA) is considered the screening test of choice for primary aldosteronism. Uncertainty exists, however, regarding its diagnostic accuracy and the effects of antihypertensive drugs and dietary sodium balance on test characteristics. METH...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:10.1373/clinchem.2004.041780
更新日期:2005-02-01 00:00:00
abstract:BACKGROUND:Extracellular vesicles (EVs) contain a rich cargo of different RNA species with specialized functions and clinical applications. However, the landscape and characteristics of extracellular vesicle long RNA (exLR) in human blood remain largely unknown. METHODS:We presented an optimized strategy for exLR sequ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.301291
更新日期:2019-06-01 00:00:00
abstract::Three groups of 10 age- and sex-matched nondiabetic volunteers took 0, 750, or 1500 mg of vitamin C each day for 12 weeks. Glycohemoglobin (GHb) was measured by HPLC, electrophoresis, affinity chromatography, and immunoassay at baseline (-4 weeks and -1 day), during supplementation (6 weeks and 12 weeks), and after su...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-05-01 00:00:00
abstract:BACKGROUND:For the past 30 years, the Sanger method has been the dominant approach and gold standard for DNA sequencing. The commercial launch of the first massively parallel pyrosequencing platform in 2005 ushered in the new era of high-throughput genomic analysis now referred to as next-generation sequencing (NGS). ...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2008.112789
更新日期:2009-04-01 00:00:00