Abstract:
:For normal and above-normal concentrations of angiotensin-converting enzyme (ACE; EC 3.4.15.1) activity in plasma, results of a manual fluorometric method [with hippuryl-histidyl-leucine (HHL), 5 mmol/L, as substrate] correlated well with those of an automated spectrophotometric method [with 3-(2-furylacryloyl)-L-phenylalanyl-glycyl-glycine (FAPGG), 2 mmol/L, as substrate]. However, for patients receiving converting enzyme inhibitor (CEI) therapy, the spectrophotometric method showed much greater suppression of plasma ACE activity than did the fluorometric method. To determine which of the two methods provided a more reliable indication of ACE inhibition in vivo, we measured plasma ACE, angiotensin I (ANG I), and angiotensin II (ANG II) in patients receiving the CEI perindopril. During perindopril therapy, changes in the ratio of ANG II:ANG I, an index of ACE activity in vivo, showed a close agreement with changes in plasma ACE activity measured with FAPGG as substrate, but not with HHL as substrate. We conclude that measurement of ACE activity in vitro with FAPGG as substrate provides a reliable measure of changes in conversion of ANG I to ANG II in vivo during CEI therapy.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Gorski TP,Campbell DJsubject
Has Abstractpub_date
1991-08-01 00:00:00pages
1390-3issue
8eissn
0009-9147issn
1530-8561journal_volume
37pub_type
杂志文章abstract:BACKGROUND:Measurement of purine and pyrimidine metabolites presents complex problems for separations currently performed by HPLC and thin-layer chromatography in clinical practice. We developed a novel capillary electrophoresis method for this purpose. METHODS:Separations were performed in 60 mmol/L borate-2-amino-2-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract:BACKGROUND:The diagnosis of 22q11 deletion syndrome (22q11DS) is often delayed or missed due to the wide spectrum of clinical involvement ranging from mild to severe, often life-threatening conditions. A delayed diagnosis can lead to life-long health issues that could be ameliorated with early intervention and treatmen...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2014.230086
更新日期:2015-01-01 00:00:00
abstract::A quantitative "high-performance" liquid-chromatographic method is described for determining porphyrins in human urine. Porphyrinogens in urine are first converted to the corresponding porphyrins by oxidation with iodine. Uroporphyrin, hepatacarboxylic acid porphyrin, hexacarboxylic acid porphyrin, pentacarboxylic aci...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
abstract::Because of uncertainty as to the molecular weight of transferrin, a previous comparison [Von der Heul et al., Clin. Chim. Acta 38, 347 (1972)] between transferrin content of serum and total iron-binding capacity cannot be definitive. We found a conversion factor for expressing the maximum amount of iron bound by 1 mg ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-07-01 00:00:00
abstract::We measured total serum bile acids on a fluorescence-light-scattering micro centrifugal analyzer by the direct enzymatic method with 3 alpha-hydroxysteroid dehydrogenase (EC 1.1.1.50) and with resazurin as a fluorogenic electron acceptor. We found that serum protein has an inhibitory effect on the measurement of bile ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-01-01 00:00:00
abstract:BACKGROUND:24,25-Dihydroxyvitamin D [24,25(OH)2D] in serum may be both a nuisance and nutritionally valuable. METHODS:We investigated the impact of 24,25(OH)2D3 on the performance of commercially available immunoassays for serum total 25-hydroxyvitamin D [25(OH)D] using (a) serum from a nationally representative sampl...
journal_title:Clinical chemistry
pub_type: 杂志文章,随机对照试验
doi:10.1373/clinchem.2014.234955
更新日期:2015-04-01 00:00:00
abstract::We describe a simple, rapid fluorometric assay for separate quantitative analysis of procainamide and N-acetylprocainamide in mixtures. The effective lenear range (fluorescence vs. concentration) in serum is 0.1 to 10.0 mg/liter, regardless of the ratio (by weight) of the two drugs from 1:10 to 10:1. Analytical recove...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-12-01 00:00:00
abstract:BACKGROUND:Because cyclosporin A (CsA) and glucocorticoids inhibit the production of interleukin-2 (IL-2) and other cytokines, quantitative analysis of cytokine mRNA might constitute a pharmacodynamic measure for immunosuppressive drug effects. We investigated whether immunosuppressive drugs influence cytokine mRNA exp...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-12-01 00:00:00
abstract::Taurine was measured in cerebrospinal fluid by reacting it with fluorescamine to form a fluorescent derivative, followed by separation on a reversed-phase column and fluorometric detection and evaluation. The assay is rapid (17 min) and sensitive to as little as 1 mumol/L. The mean value for 27 cerebrospinal fluid sam...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-08-01 00:00:00
abstract:BACKGROUND:Plasma creatinine concentration and calculated creatinine clearance are of limited value as glomerular filtration rate (GFR) markers in patients with decompensated liver cirrhosis. We assessed plasma cystatin C as an indicator of GFR in such patients. METHODS:We studied 36 patients with decompensated liver ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-06-01 00:00:00
abstract::In this simple and low-cost radioimmunoassay (RIA) procedure for thyroxin (T4), ethacridine (6,9-diamino-2-ethoxyacridine lactate; Rivanol) is used to separate antibody-bound ligand and free ligand. This acridine dye precipitates free T4 not bound to antibody. At pH 8.6, it precipitates more than 90% of 125I-labeled T...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-11-01 00:00:00
abstract::We describe the measurement of human immunoglobulins IgG, IgA, and IgM in diluted sera, with diluted commercial monospecific antisera, with use of a 36-place centrifugal analyzer (RotoChem IIa; American Instrument Co., Silver Spring, MD 20920). The assay involves a two-point kinetic turbidimetric technique. The change...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00
abstract:BACKGROUND:Different technologies, such as quantitative real-time PCR or microarrays, have been developed to measure microRNA (miRNA) expression levels. Quantification of miRNA transcripts implicates data normalization using endogenous and exogenous reference genes for data correction. However, there is no consensus ab...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2015.239459
更新日期:2015-11-01 00:00:00
abstract::Six different procedures for radioiodination of mouse epidermal growth factor (EGF) all resulted in a heterogeneous 125I-labeled EGF preparation, as analyzed by reversed-phase HPLC. EGF preparations that had been iodinated with Chloramine T, lodogen, or lodo-beads were found mainly to consist of oxidized 125I-labeled ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-05-01 00:00:00
abstract::Ingestion of oleander plant, containing the cardiac glycoside oleandrin, has been reported to induce fatal poisonings. Derivatives of oleandrin are structurally similar to digoxin. We investigated the cross-reactivities of oleandrin and its aglycone metabolite, oleandrigenin, in several commercially available digoxin ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-10-01 00:00:00
abstract::Purified arylsulfatase A (EC 3.1.6.1) from human urine was radioiodinated under conditions that caused no significant loss of antigenic activity. We used this labeled arylsulfatase A (specific radioactivity 4-7.5 Ci/g) together with nonlabeled enzyme and rabbit antiserum produced against homogeneous enzyme to develop ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-03-01 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:BACKGROUND:New genetic forms of hereditary hemochromatosis (HH) or hereditary hyperferritinemia (HF) have been identified over the last few years, and abnormalities of various genes may interact in a single patient. This study aimed to develop a rapid automated method for sequencing the main genes involved. METHODS:We...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.090605
更新日期:2007-12-01 00:00:00
abstract::We compared different sample-handling techniques for measurement of Na+ and K+ with ion-selective electrodes (ISE). Imprecision was less for venous blood (with a minimum of heparin) than for plasma, serum, or capillary blood. The results for K+ were higher for serum than for whole blood, and higher for whole blood tha...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-03-01 00:00:00
abstract:BACKGROUND:Atherosclerosis is a complex, chronic disease that usually arises from the converging action of several pathogenic processes, including hypertension, hyperlipidemia, obesity, and the accumulation of oxidized LDL. Platelet-activating factor acetylhydrolase (PAF-AH) is a LDL- and HDL-bound enzyme that hydrolyz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.036863
更新日期:2004-11-01 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::Immunoradiometric analysis has made it possible to measure ferritin reliably in serum. The determination is a sensitive means of assessing body iron because concentrations of ferritin closely parallel the body's reticuloendothelial iron stores. The information provided is similar to that obtained from bone-marrow aspi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-01-01 00:00:00
abstract::To demonstrate oligoclonal IgG bands (I) in unconcentrated cerebrospinal fluid, we used isoelectric focusing in agarose followed by protein transfer to cellulose nitrate membrane, double-antibody peroxidase labeling, and avidin-biotin amplification. I can be reliably seen after isoelectric focusing of 5-microL specime...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-07-01 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::Creatine kinase (CK; EC 2.7.3.2) has been used as an indicator of myocardial cellular damage. In this study we used a Krebs-Henseleit (KH) solution to reperfuse isolated rat hearts after 24 h of cold preservation and collected the KH reperfusate for assay of CK to assess cellular damage. We wanted to determine the sta...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::We evaluated and compared five commercial radioimmunoassay kits with a standard counter-immunoelectrophoretic assay for the measurement of prostatic acid phosphatase in serum. Four of the five radioimmunoassays performed as described by the supplier with respect to sensitivity, stability, precision, linearity, analyti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-10-01 00:00:00
abstract::A novel noninstrumented technology (ChemTrak AccuMeter) for the quantitative measurement of analytes in biological fluids was reported at the 1990 Oak Ridge Conference (Clin Chem 1990;36:1591-7). This instrument-free technology has been adapted for the quantitative measurement of high-density lipoprotein (HDL). An in ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-09-01 00:00:00
abstract::We evaluated a new kinetic assay for alpha-amylase (Phadebas IsoAmylase Test), using modified starch as the substrate and a CentrifiChem 400 centrifugal analyzer system. We determined isoamylase activities by using a selective inhibitor. Results were compared with those obtained with the chromogenic Phadebas dyed-star...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-06-01 00:00:00
abstract:BACKGROUND:The single cell represents the basic unit of all organisms. Most investigations have been performed on large cell populations, but understanding cell dynamics and heterogeneity requires single-cell analysis. Current methods for single-cell analysis generally can detect only one class of analytes. METHODS:Re...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.191445
更新日期:2012-12-01 00:00:00
abstract:BACKGROUND:Dried blood spots (DBS) are a convenient and inexpensive method for biobanking. Although many countries have established population-based DBS biobanks from neonatal screening programs, the quality and usefulness of DNA from DBS have not been extensively assessed. METHODS:We compared 4 common DNA extraction ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.087510
更新日期:2007-08-01 00:00:00