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. Nineteen metabolites were detected in urine after intramuscular injection, and eight metabolites were identified. For this purpose, preparative HPLC, mass spectrometry with different ionization modes (electronic impact and chemical ionization), and different acquisition techniques were used (high resolution, selected ion monitoring, and scan measurement). Metabolite stereoisomerism was determined on the basis of retention time and organic synthesis. 4-Chloroepitestosterone (M2), 4-chloroandrost-4-en-3alpha-ol-17-one (M3), and 4-chloroandrost-4-ene-3,17-dione (M4) were identified as the main urinary markers of intramuscular administration. On the other hand, 4-chloroandrost-4-ene-3alpha,17beta-diol (M7), 4-chloroandrostan-3beta-ol-17-one (M5), and M2 were the primary indicators of an oral administration. In addition, we have shown that 95% of the metabolites were sulfo-conjugated, except for M3, which was partially conjugated to glucuronic acid. Finally, the main metabolites (M2, M3, and M4) were easily identified for 1.5 months after intramuscular administration.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Le Bizec B,Montrade MP,Monteau F,Gaudin I,Andre Fsubject
Has Abstractpub_date
1998-05-01 00:00:00pages
973-84issue
5eissn
0009-9147issn
1530-8561journal_volume
44pub_type
杂志文章abstract::Red blood cell (RBC) replacement solutions are being developed as alternatives to allogeneic RBC use in blood transfusions in the treatment of massive trauma, to achieve hemodynamic stability during elective surgery, and to increase oxygen-carrying capacity in anemia. Hemoglobin-based oxygen carrier (HBOC)-201 (Biopur...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::We evaluated a dual-precipitation method for determining cholesterol in high-density lipoprotein (HDL) and its subfractions HDL2 and HDL3. After total HDL was isolated by precipitation of very-low-density (VLDL) and low-density (LDL) lipoproteins with polyethylene glycol (Mr 8000), HDL2 was isolated from total HDL by ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-11-01 00:00:00
abstract:BACKGROUND:Dopa-responsive dystonia (DRD) and tetrahydrobiopterin (BH4) defects are inherited disorders characterized by monoamine neurotransmitter deficiency with decreased activity of one of the BH4-metabolizing enzymes. The aim of the study was to determine the utility of cultured skin fibroblasts for the diagnosis ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2001-03-01 00:00:00
abstract::During direct illumination of a serum bilirubin solution the bilirubin concentration decreased markedly, both as determined by the direct spectrometric method and (even more so) by the diazo method. In contrast, I found the same values for serum bilirubin concentrations as determined by these two methods for serum fro...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-01-01 00:00:00
abstract::We measured the rate of elimination of phenylalanine by constant intravenous infusion of L-phenylalanine in 14 parents of children with phenylketonuria and in 21 subjects with a negative family history for this disease. When reciprocals of the observed elimination rates were plotted against the reciprocals of the incr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-09-01 00:00:00
abstract:BACKGROUND:The liver is frequently subject to insult because of viral infection, alcohol abuse, or toxic chemical exposure. Extensive research has been conducted to identify blood markers that can better discern liver damage, but little progress has been achieved in clinical practice. Recently, circulating microRNAs (m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.147850
更新日期:2010-12-01 00:00:00
abstract::Seeking to minimize degradation of NADPH during storage, reagent preparation, and assays, we investigated the effects of pH, temperature, and ionic strength as well as the effects of phosphate and acetate. NADH was also included for comparison. Our results indicate that the rate of degradation of NADPH is proportional...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
abstract::Patients' sera were analyzed for carbamazepine and ethosuximide by enzyme immunoassay (x) and gas chromatography (y), and the results were compared. The correlation coefficients were: for carbamazepine, x vs. y 0.94 (n = 93); for ethosuximide, x vs. y 0.99 (n = 30). These results suggest that the two methods could be ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-09-01 00:00:00
abstract:BACKGROUND:We used a difference in bias approach to evaluate the commutability of 4 frozen serum pools for 8 direct methods for measurement of HDL and LDL cholesterol (HDLC and LDLC). METHODS:Freshly collected nonfrozen sera from 138 diseased and 37 nondiseased patients and 4 frozen pools from the CDC Lipid Standardiz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.240861
更新日期:2015-08-01 00:00:00
abstract::Advanced glycosylation end products (AGEs) are thought to play an important role in the development of diabetic complications. Oxidative reactions are essential for the formation of some AGEs, termed glycoxidation products. Increased concentrations of pentosidine, one of such products, are found in tissue and serum in...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::We report the accuracy, imprecision, total analytical errors, and patient misclassification errors for cholesterol measured from capillary whole blood, venous whole blood, and venous plasma samples by five devices used in public cholesterol screening environments: Reflotron, Vision, Ektachem DT-60, QuickRead, and Lipo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-02-01 00:00:00
abstract::A one-stage semiautomated method for estimating total phospholipids in plasma is reported. The phospholipids are extracted into aqueous ethanol, combined with a Lewis acid, and the change in pH is monitored colorimetrically. The method, compared with the acid digestion method of Gomori [J. Lab. Clin. Med. 27, 955 (194...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-09-01 00:00:00
abstract::Clinicians confront the classical problem of decision making under uncertainty, but a universal procedure by which they deal with this situation, both in diagnosis and therapy, can be defined. This consists in the choice of a specific course of action from available alternatives so as to reduce uncertainty. Formal ana...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1995-08-01 00:00:00
abstract::A modified agarose electrophoretic system for the separation of alkaline phosphatase (ALP, EC 3.1.3.1) isoenzymes is described. Bone, liver, high-molecular-mass, and intestinal ALP are separated with high reproducibility. The sensitivity of the agarose system is superior to cellulose acetate in detecting high-Mr ALP. ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-09-01 00:00:00
abstract::We measured advanced glycosylation end products in the mesenteric artery of 37 patients (ages 29-82 years), 34 of whom were nondiabetic. Samples of arterial tissue were obtained during bowel resectioning. Advanced glycosylation end products were measured as collagen-linked fluorescence (excitation wavelength 370 nm, e...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-04-01 00:00:00
abstract::Direct-injection analysis for phenylalanine in plasma by isocratic "high-performance" liquid chromatography (HPLC) is described. For chromatographic separation I use an internal-surface reversed-phase silica support. The method involves ultraviolet detection, requires as little as 10 microL of plasma (routinely 20 mic...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-06-01 00:00:00
abstract::We measured cyclosporine in whole blood from normal volunteers administered single oral doses of the drug and from two renal-transplant patients on immunosuppressive maintenance therapy, by liquid chromatography (I) and by radioimmunoassay with use of nonspecific polyclonal (II), specific monoclonal (III), and nonspec...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-12-01 00:00:00
abstract::We evaluated the EMIT (enzyme-multiplied immuno technique) and FPIA (fluorescence polarization immunoassay) urine screening systems for detection of benzodiazepine intake. Healthy male volunteers were given single oral therapeutic doses of alprazolam (2 mg), chlordiazepoxide (25 mg), flunitrazepam (1 mg), lorazepam (3...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-02-01 00:00:00
abstract::The reaction of 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB, Ellman's reagent) with thiols is sensitive to daylight, in particular to ultraviolet radiation at wavelengths around 325 nm. Exposure to light at the absorbance maximum of the yellow product (the thionitrobenzoate ion) at 410 nm had no effect on the reaction. ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::We describe an enzymic assay for the functional activity of alpha 1-antitrypsin, in which tosyl-Gly-Pro-Lys-p-nitroanilide acetate (Chromozym PL) is the trypsin substrate. For the indicating reaction, the concentration of substrate is about double the Km of its reaction with trypsin. This assay is an improvement over ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
abstract::Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also desc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-07-01 00:00:00
abstract::We evaluated the new Greiner G-400 selective multichannel analyzer. Thirty different tests can be run in combination profile and single-test mode at a rate between 150 and 300 tests per hour. The new photometer allows kinetic and equilibrium (endpoint) measurements. The G-400 analyzer demonstrated excellent precision,...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-02-01 00:00:00
abstract::We describe a rapid method for determining cholesterol sulfate in plasma and erythrocytes. After its single-step isolation by means of anion-exchange chromatography cholesterol sulfate is hydrolyzed, trimethylsilylated, and determined by gas chromatography with flame ionization detection. 5 beta-Cholestan-3 alpha-ol s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-07-01 00:00:00
abstract::Numerous outcome measures can be used to characterize and compare the performance of alternative quality-control (QC) strategies. The performance measure traditionally used in the QC planning process is the probability of rejecting an analytical run when a critical out-of-control error condition exists. Another perfor...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-04-01 00:00:00
abstract::Using Syva "EMIT" reagents and the Cobas Bio centrifugal analyzer, we have developed cost-effective assays for therapeutic drug monitoring of carbamazepine, phenobarbital, and phenytoin. With these optimized methods one can assay up to 2470 samples with a single 100-test EMIT kit with good precision and accuracy. Betw...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
abstract:BACKGROUND:Plant-derived cardenolides reportedly possess anticancer properties in human leukemic cells via selective induction of apoptosis, cell cycle arrest, and differentiation. Selective induction of apoptosis with mammalian-derived digoxin-like immunoreactive factor (DLIF) could provide new strategies for anticanc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.082081
更新日期:2007-07-01 00:00:00
abstract::We evaluated a new, simple, enzymatic kinetic method from Wako Chemicals GmbH in comparison with a kinetic Jaffé method by using isotope dilution-mass spectrometry (ID-MS) as a reference method. An ID-MS-calibrated serum standard was used. Both the enzymatic and the Jaffé method correlated well with ID-MS, except for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract:BACKGROUND:The B-type natriuretic peptides (BNP and N-terminal pro-BNP) are secreted by the heart and, in the case of BNP, serve to maintain circulatory homeostasis through renal and vascular actions and oppose many effects of the renin-angiotensin system. Recent evidence suggests that in patients with severe heart fai...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.210435
更新日期:2014-03-01 00:00:00
abstract:BACKGROUND:Next generation sequencing (NGS)-based assays continue to redefine the field of genetic testing. Owing to the complexity of the data, bioinformatics has become a necessary component in any laboratory implementing a clinical NGS test. CONTENT:The computational components of an NGS-based work flow can be conc...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2014.224360
更新日期:2015-01-01 00:00:00
abstract::Quinidine in serum was measured at 330 nm, after protein precipitation, with an alkyl phenyl reversed-phase chromatographic column by peak-height determination (external standards.) Sensitivity was 0.3 mg/liter, with linear response to at least 10 mg/liter serum. Interassay precision, measured on 20 consecutive days, ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00