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Showing papers by "Andrew T. Kicman published in 2017"


Journal ArticleDOI
TL;DR: The LC-FAIMS-MS method demonstrates increases in signal-to-noise ratios for the doubly sodiated steroid metabolites in unspiked urine (>250%) by the reduction of isobaric interferences from the matrix.
Abstract: The combination of field asymmetric waveform ion mobility spectrometry with liquid chromatography–mass spectrometry (LC-FAIMS-MS) has been developed for the analysis of glucuronide and sulfate metabolites of seven anabolic-androgenic steroids in urine. Separation by FAIMS-MS was investigated in positive ion mode for selected cationic adducts (H+, NH4+, Na+, K+, and Cs+). LC-FAIMS-MS analysis of the doubly sodiated adducts ([M + 2Na – H]+) of isobaric and coeluting steroid metabolites allowed their rapid (8 min) qualitative and quantitative determination in spiked urine using hydrophilic interaction liquid chromatography prior to FAIMS-MS separation, with discrimination >95% achieved between the steroids investigated. A quantitative evaluation of the LC-FAIMS-MS method was performed giving limits of detection in the range 1–6 ng mL–1, limits of quantification in the range 3–20 ng mL–1, with reproducibility (%RSD 0.99). The LC-FAIMS-MS method demonstrates increases in signa...

26 citations


Journal ArticleDOI
TL;DR: In this article, an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantify testosterone (T) and epitestosterone (E).
Abstract: Detection of testosterone and/or its pro-drugs in the gelding is currently regulated by the application of an international threshold for urinary testosterone of 20 ng/mL. The use of steroid ratios may provide a useful supplementary approach to aid in differentiating between the administration of these steroids and unusual physiological conditions that may result in atypically high testosterone concentrations. In the current study, an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantify testosterone (T) and epitestosterone (E). The method was used to analyze 200 post-race urine samples from geldings in order to generate the ratios for the reference population. Following statistical analysis of the data, an upper limit of 5 for T:E ratio in geldings is proposed. Samples collected from 15 geldings with atypical urinary testosterone concentrations (>15 ng/mL) but otherwise normal steroid profile, had T:E ratios within those observed for the reference population. The applicability of an upper T:E ratio to detect an administration was demonstrated by the analysis of a selection of incurred samples from testosterone propionate, dehydroepiandrosterone (DHEA), and a mixture of DHEA and pregnenolone (Equi-Bolic®) administrations. These produced testosterone concentrations above the threshold of 20 ng/mL, but also T:E ratios above the proposed limit of 5. In conclusion, consideration of the T:E ratio appears to be a valuable complementary aid to evaluate whether an atypical testosterone concentration could be caused by a natural biological outlier as opposed to the administration of these steroids. Copyright © 2016 John Wiley & Sons, Ltd.

12 citations


Journal ArticleDOI
TL;DR: GHB administration at a small therapeutic dose results in increases in serum GH concentrations in healthy male and female volunteers in the absence of sleep onset.
Abstract: The administration of gamma-hydroxybutyrate (GHB) has been reported to augment the increase in growth hormone (GH) secretion associated with the onset of sleep. The ability of GHB to stimulate GH production in the absence of sleep in both male and female volunteers was investigated as part of a GHB administration study. Twelve healthy volunteers (six men and six women) were given a small oral dose (25 mg/kg) of GHB (as Xyrem®) at 10:00 h. Basal blood samples (as serum) were taken 10 min prior to GHB administration, with additional samples taken at 10, 15, 20, 25, 30, 45, 60, 90, 120, 150, 180, 240, 360 and 480 min post-administration. The serum concentrations of GHB were measured by GC-MS and GH by immunometric assay. Following GHB administration, volunteers exhibited effects consistent with mild sedation, i.e., relaxed with normal responses to verbal stimuli. Despite none being asleep, an increase in serum GH concentration occurred in 11 out of the 12 volunteers (5 women and 6 men). In these volunteers, peak GH concentrations occurred 45-60 min post-administration compared with a mean serum tmax for GHB of 23 min (SD = 5.4 min). The absolute increase in GH was similar for men and women, averaging 3.4 and 3.7 ng/mL, respectively. The mean intra-individual increase in GH was much greater in males (29 times) compared with females (2 times), as males had (as expected) smaller basal GH concentrations (mean = 0.26 ng/mL) compared with females (mean = 5.4 ng/mL). After maximizing, the GH concentration decreased rapidly (in agreement with GHB concentrations), returning to basal concentrations at ~90-120 min post-administration. GHB administration at a small therapeutic dose results in increases in serum GH concentrations in healthy male and female volunteers in the absence of sleep onset.

10 citations