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- Thevis, M., et al.
(författare)
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Nickel in equine sports drug testing - pilot study results on urinary nickel concentrations
- 2016
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Ingår i: Rapid Communications in Mass Spectrometry. - : Wiley. - 0951-4198 .- 1097-0231. ; 30:7, s. 982-984
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Tidskriftsartikel (refereegranskat)abstract
- RationaleThe issue of illicit performance enhancement spans human and animal sport in presumably equal measure, with prohibited substances and methods of doping conveying both ways. Due to the proven capability of unbound ionic cobalt (Co2+) to stimulate erythropoiesis in humans, both human and equine anti-doping regulations have listed cobalt as a banned substance, and in particular in horse drug testing, thresholds for cobalt concentrations applying to plasma and urine have been suggested or established. Recent reports about the finding of substantial amounts of undeclared nickel in arguably licit performance- and recovery-supporting products raised the question whether the ionic species of this transition metal (Ni2+), which exhibits similar prolyl hydroxylase inhibiting properties to Co2+, has been considered as a substitute for cobalt in doping regimens. MethodsTherefore, a pilot study with 200 routine post-competition doping control horse urine samples collected from animals participating in equestrian, gallop, and trotting in Europe was conducted to provide a first dataset on equine urinary Ni2+ concentrations. All specimens were analyzed by conventional inductively coupled plasma mass spectrometry (ICP-MS) to yield quantitative data for soluble nickel. ResultsConcentrations ranging from below the assay's limit of quantification (LOQ, 0.5 ng/mL) up to 33.4 ng/mL with a mean value ( standard deviation) of 6.1 (+/- 5.1) ng/mL were determined for the total nickel content. ConclusionsIn horses, nickel is considered a micronutrient and feed supplements containing nickel are available; hence, follow-up studies are deemed warranted to consolidate potential future threshold levels concerning urine and blood nickel concentrations in horses using larger sets of samples for both matrices and to provide in-depth insights by conducting elimination studies with soluble Ni2+-salt species.
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- Guddat, S., et al.
(författare)
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Synthesis, characterization, and detection of new oxandrolone metabolites as long-term markers in sports drug testing
- 2013
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:25, s. 8285-8294
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Tidskriftsartikel (refereegranskat)abstract
- The discovery and implementation of the long-term metabolite of metandienone, namely 17 beta-hydroxymethyl-17 alpha-methyl-18-norandrost-1,4,13-trien-3-one, to doping control resulted in hundreds of positive metandienone findings worldwide and impressively demonstrated that prolonged detection periods significantly increase the effectiveness of sports drug testing. For oxandrolone and other 17-methyl steroids, analogs of this metabolite have already been described, but comprehensive characterization and pharmacokinetic data are still missing. In this report, the synthesis of the two epimeric oxandrolone metabolites-17 beta-hydroxymethyl-17 alpha-methyl-18-nor-2-oxa-5 alpha-androsta-13-en-3-one and 17 alpha-hydroxymethyl-17 beta-methyl-18-nor-2-oxa-5 alpha-androsta-13-en-3-one-using a fungus (Cunninghamella elegans) based protocol is presented. The reference material was fully characterized by liquid chromatography nuclear magnetic resonance spectroscopy and high resolution/high accuracy mass spectrometry. To ensure a specific and sensitive detection in athlete's urine, different analytical approaches were followed, such as liquid chromatography-tandem mass spectrometry (QqQ and Q-Orbitrap) and gas chromatography-tandem mass spectrometry, in order to detect and identify the new target analytes. The applied methods have demonstrated good specificity and no significant matrix interferences. Linearity (R (2) > 0.99) was tested, and precise results were obtained for the detection of the analytes (coefficient of variation < 20 %). Limits of detection (S/N) for confirmatory and screening analysis were estimated at 1 and 2 ng/mL of urine, respectively. The assay was applied to oxandrolone post-administration samples to obtain data on the excretion of the different oxandrolone metabolites. The studied specimens demonstrated significantly longer detection periods (up to 18 days) for the new oxandrolone metabolites compared to commonly targeted metabolites such as epioxandrolone or 18-nor-oxandrolone, presenting a promising approach to improve the fight against doping.
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- Knych, Heather K., et al.
(författare)
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Pharmacokinetics and pharmacodynamics of meldonium in exercised thoroughbred horses
- 2017
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Ingår i: Drug Testing and Analysis. - : John Wiley & Sons. - 1942-7603 .- 1942-7611. ; 9:9, s. 1392-1399
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Tidskriftsartikel (refereegranskat)abstract
- Although developed as a therapeutic medication, meldonium has found widespread use in human sports and was recently added to the World Anti-Doping Agency's list of prohibited substances. Its reported abuse potential in human sports has led to concern by regulatory authorities about the possible misuse of meldonium in equine athletics. The potential abuse in equine athletes along with the limited data available regarding the pharmacokinetics and pharmacodynamics of meldonium in horses necessitates further study. Eight exercised adult thoroughbred horses received a single oral dose of 3.5, 7.1, 14.3 or 21.4 mg/kg of meldonium. Blood and urine samples were collected and analyzed using liquid chromatography tandem mass spectrometry. Pharmacokinetic parameters were determined using non-compartmental analysis. Maximum serum concentrations ranged from 440.2 to 1147 ng/mL and the elimination half-life from 422 to 647.8 h. Serum concentrations were below the limit of quantitation by days 4, 7, 12 and 12 for doses of 3.5, 7.1, 14.3 and 21.4 mg/kg, respectively. Urine concentrations were below the limit of detection by day 44 following administration of 3.5 mg/kg and day 51 for all other dose groups. No adverse effects were observed following meldonium administration. While the group numbers were small, changes in heart rate were observed in the 3.5 mg/kg dose group (n = 1). Glucose concentrations changed significantly in all dose groups studied (n = 2 per dose group). Similar to that reported for humans, the detection time of meldonium in biological samples collected from horses is prolonged, which should allow for satisfactory regulation in performance horses. Copyright (C) 2017 John Wiley & Sons, Ltd.
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