Abstract：
BACKGROUND:Our previously developed assay for detection of the factor V Leiden mutation (G1691A) based on a nucleic acid photo-cross-linking technology used two allele-specific capture probes and six fluorescein-modified signal-generating reporter probes. We wished to improve the sensitivity and performance of the method. METHODS:We developed new reporter probes with approximately 10-fold more fluorescein molecules than the original probes. The single, cross-linker-modified capture probe was replaced by a three-probe system, separating the probe-target cross-linking function and the allelic differentiation function. The capture probe cross-linked to either or both of two flanking probes through stem structures at the capture-probe/flanking-probe junctions. The flanking probes cross-linked to target DNA through two cross-linking sites each. Genomic DNA was extracted from 0.2 mL of whole blood and restriction-enzyme digested to create a defined 677 bp target sequence. Preliminary genotype ranges were determined for the assay by testing of pre-typed samples. We then tested 1054 clinical samples, using an automated sample processor. RESULTS:The new assay had a 10-fold increase in signal-to-background ratio. Genotype results for 1039 of 1054 clinical samples (98.6%) agreed with those of a PCR-based method. Of the 15 remaining samples, 10 produced an indeterminate result outside the defined genotype ranges, 2 yielded insufficient signal to be genotyped, and 3 gave a discordant result. All 15 samples were genotyped correctly after re-extraction of genomic DNA and retesting. CONCLUSION:The modified photo-cross-linking assay for factor V Leiden detection is a sensitive non-PCR-based assay with potential for use in high-throughput clinical laboratories.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
French C,Li C,Strom C,Sun W,Van Atta R,Gonzalez B,Wood Mdoi
10.1373/clinchem.2003.023556subject
Has Abstractpub_date
2004-02-01 00:00:00pages
296-305issue
2eissn
0009-9147issn
1530-8561pii
clinchem.2003.023556journal_volume
50pub_type
杂志文章abstract：BACKGROUND:Detection of circulating tumor cells (CTCs) in the peripheral blood is a rapidly developing research field with clear clinical implications for the staging and monitoring of cancer patients. Current CTC assays, including the US Food and Drug Administration-cleared CellSearch® system, typically use markers [e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.175570
更新日期：2012-05-01 00:00:00
abstract：:Values for insulin-mediated glucose disposal vary continuously throughout a population of apparently healthy individuals, with at least a sixfold variation between the most insulin sensitive and most insulin resistant of these individuals. The more insulin resistant a person, the more insulin must be secreted to preve...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2005.048611
更新日期：2005-06-01 00:00:00
abstract：:We compared cotinine, carboxyhemoglobin, and thiocyanate concentrations in blood sampled from 187 cigarette smokers and 181 non-smokers. All three differed significantly between smokers and non-smokers. Cotinine performed best as a test for assessing smoking status, with a sensitivity of 98% as compared with 94% for c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-08-01 00:00:00
abstract：:Erythrocyte protoporphyrin content is increased in several human and veterinary disorders in which heme synthesis is disrupted. The nature of the defect determines whether zinc protoporphyrin, unchelated (free) protoporphyrin, or both are present in the erythrocytes. Extraction of the protoporphyrin into acetone/water...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-02-01 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：:We describe an improved separation of the isoenzymes of aspartate aminotransferase (EC 2.6.1.1), based on ion-exchange chromatography. Involving the "Fast Protein Liquid Chromatography" system (Pharmacia) with a MonoQ column, this rapid, reproducible method for quantifying the mitochondrial enzyme shows good resolutio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-02-01 00:00:00
abstract：BACKGROUND:The susceptibility of plasma lipids to oxidation is thought to be a factor contributing to atherogenic risk. Various groups have studied the in vitro oxidizability of isolated LDL and examined the effects of conventional antioxidants. The drawbacks associated with the isolation of LDL for evaluation of in vi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.051078
更新日期：2005-11-01 00:00:00
abstract：BACKGROUND:The kidney performs a multitude of essential functions to maintain homeostasis. In clinical medicine, glomerular filtration rate (GFR) provides the best index of overall kidney function, and proteinuria adds additional information on renal and nonrenal prognosis. Several novel biomarkers of kidney injury and...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2011.167494
更新日期：2012-04-01 00:00:00
abstract：BACKGROUND:Although cardiac troponin (cTn) is a cornerstone marker in the assessment and management of patients with acute coronary syndrome (ACS) and heart failure (HF), cTn is not diagnostically specific for any single myocardial disease process. This narrative review discusses increases in cTn that result from acute...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2009.130799
更新日期：2009-12-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-08-01 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:Δ(9)-Tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), and cannabinol (CBN) were measured in breath following controlled cannabis smoking to characterize the time course and windows of detection of breath cannabinoids. METHODS:Exhaled breath was collected from chronic (≥4 times per week) and occas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.207407
更新日期：2013-12-01 00:00:00
abstract：BACKGROUND:Lysosomal storage disorders (LSDs) comprise more than 40 genetic diseases that result in the accumulation of products that would normally be degraded by lysosomal enzymes. A tandem mass spectrometry (MS/MS)-based method is available for newborn screening for 5 LSDs, and many laboratories are initiating pilot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.111864
更新日期：2009-01-01 00:00:00
abstract：:We describe a sensitive method for the determination of vanadium in biological substances by atomic absorption spectroscopy. By using background correction and pyrolytically coated graphite tubes with flameless apparatus, this vanadium assay has a sensitivity of 65 pg and a detection limit of 30 pg, approximately sixf...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 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：:Diagnosing cobalamin deficiency is often difficult. We investigated the diagnostic strategies that 224 general practitioners used to assess cobalamin status and the criteria on which they based their decisions to supplement patients. From all serum cobalamin analyses carried out at a single laboratory during 1993, ind...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-02-01 00:00:00
abstract：:We studied the effects of some chelators on creatine kinase activity. Creatine kinase is competitively inhibited by endogenous polyvalent cations (e.g., calcium, Ki = 4.5 mmol/L); this can be reversed by adding chelators to the reagent, resulting in a mean increase in activity of 1.14-fold at 25 degrees C and 1.18-fol...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-03-01 00:00:00
abstract：BACKGROUND:Single-nucleotide polymorphisms (SNPs) in inflammation-related genes have been linked to an increased risk of ischemic stroke. Most of these SNP results have not been replicated, however, and metaanalyses of the effects of inflammation-related genes are rare. We investigated 49 SNPs in 34 genes previously re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.112151
更新日期：2009-01-01 00:00:00
abstract：:We report a survey on urine drug testing within a total of 269 laboratories of the European Union. Clinical laboratories predominated over forensic laboratories (59.5% vs 28.5%). Screening without identification/quantification was the common approach used by clinical laboratories, whereas screening with identification...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-04-01 00:00:00
abstract：BACKGROUND:Quantification of 5-hydroxyindole-3-acetic acid (5-HIAA) in urine is useful in diagnosing and monitoring of patients with carcinoid tumors and in the study of serotonin (5-hydroxytryptamine) metabolism in various disorders. We describe an automated method that incorporates on-line solid-phase extraction (SPE...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.050062
更新日期：2005-09-01 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：BACKGROUND:Rapid intraoperative parathyroid hormone (PTH) measurements are an important prerequisite for minimally invasive parathyroidectomy, serving as a feasible marker for "cure" because of the short half-life of PTH. Because automated analysis may facilitate monitoring, two automated PTH assays were compared with ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-10-01 00:00:00
abstract：:Two patients with Paget's disease of bone were subjected to plasmapheresis. Alkaline phosphatase activities of serum declined sharply, but returned to preplasmapheresis values within eight to 10 days. The biological half-life of circulating skeletal alkaline phosphatase, as calculated from these experiments, is betwee...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：:We describe a simple fluoroimmunoassay for the determination of thyroxine concentrations in serum. The method, "sequential addition, separation fluoroimmunoassay," involves both thyroxine labeled with fluorescein and magnetizable cellulose/iron oxide particles to which antibodies to thyroxine have been covalently link...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-11-01 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：:Four assay procedures for tobramycin in serum--enzyme immunoassay (I), substrate-labeled fluorescent immunoassay (II), radioimmunoassay (III), and bioassay (IV)--were compared and evaluated by replicate and analytical recovery studies. I and II were about 50% more precise than III and IV. II was substantially more nea...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：:We report results of a quality-control survey of radioimmunoassay (RIA) of eight analytes, participated in by 249 laboratories of various types throughout Japan. For the purpose of the external control survey, lyophilized specimens containing two different concentrations of each analyte were sent to the participating ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-08-01 00:00:00
abstract：:Alanine aminotransferase activity in serum increases significantly when serum is incubated with pyridoxal phosphate. The increase depends on the L-alanine concentration in the final assay mixture, being greatest at 800 mmol/liter. Preincubation of 22 normal sera, in a 10:1 ratio with an 8.09 mmol/liter pyridoxal phosp...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-02-01 00:00:00
abstract：BACKGROUND:The Elecsys beta-CrossLaps serum assay measures type I collagen degradation fragments (beta-CTx) that contain the beta-isomerized octapeptide EKAHD-beta-GGR. We investigated the analytical performance of the assay and changes in beta-CrossLaps in patients with metabolic bone diseases. METHODS:The electroche...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：2001-08-01 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
