Caroline K. Hatton
University of California, Los Angeles
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Featured researches published by Caroline K. Hatton.
Journal of Mass Spectrometry | 1996
Rodrigue Aguilera; Michel Becchi; Hervé Casabianca; Caroline K. Hatton; Don H. Catlin; Borislav Starcevic; Harrison G. Pope
The current approach to detection of doping with testosterone is based on measuring the testosterone to epitestosterone ratio (T/E) in urine by gas chromatography/mass spectrometry. The median T/E for healthy males who have not used T is about 1.0. In a single urine, a T/E lower than six leads to a negative report even though it does not exclude T administration. A value greater than six indicates possible T administration or a naturally elevated ratio. It has been shown previously that the carbon isotope ratio of urinary T changes after T administration. In this study a potential confirmation method for T abuse was optimized. Gas chromatography/combustion/carbon isotope ratio mass spectrometry (GC/C/IRMS) was used to analyze two T precursors (cholesterol and 5-androsten-3 beta, 17 beta-diol) and two T metabolites (5 alpha- and 5 beta-androstane-3 alpha, 17 beta-diol) in addition to T itself in each of 25 blind urines collected from eight healthy men before, during or after T administration. The carbon isotope ratios of T and the metabolites were lower after T administration. The relationships among the variables were studied using multivariate analysis and beginning with principal components analysis; cluster analysis revealed that the data are composed of two clusters, and classified the samples obtained after T administration in one cluster and the remainder in the other; discriminant analysis correctly identified T users. The measurement of carbon isotope ratios of urinary androgens is comparable to the T/E > 6 test and continues to show promise for resolving cases where doping with T is suspected.
Journal of Chromatography B: Biomedical Sciences and Applications | 1999
Rodrigo Aguilera; Don H. Catlin; Michel Becchi; Andy Phillips; Cristina Wang; Ronald S. Swerdloff; Harrison G. Pope; Caroline K. Hatton
We propose a new screening method for testosterone (T) doping in sport. The current method for detecting T administration is based on finding a T to epitestosterone ratio (T/E) in urine that exceeds six. The difficulties with T/E are that T administration does not always result in a T/E>6 and that a rare individual will have T/E>6 in the absence of T administration. Our previous studies reveal that carbon isotope ratio helps to determine the origin of the urinary T because the values for T and its metabolites decrease after the administration of exogenous T. In this study, we present a rapid and efficient screening sample preparation method based on three successive liquid-solid extractions, deconjugation with E. coli beta-glucuronidase after the first extraction, acetylation after the second extraction, and a final extraction of the acetates. The 13C/12C of two T metabolites (5beta-androstane-3alpha,17beta-diol and 5alpha-androstane-3alpha,17beta-diol) and one pregnanediol as endogenous reference (5beta-pregnane-3alpha,20alpha-diol) was measured by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) on 10 ml of urine collected from 10 healthy men before and after T administration. Following T administration, the 13 C/12C of 5beta-androstane-3alpha,17beta-diol diacetate and 5alpha-androstane-3alpha,17beta-diol diacetate declined significantly from -26.2 per thousand to -30.8 per thousand and from -25.2 per thousand to -29.9 per thousand, respectively and the 13C/12C of 5beta-pregnane-3alpha,20alpha-diol diacetate was unchanged. In addition, the ratio of androstanediols to pregnanediol increased in the post-T urines.
Journal of Mass Spectrometry | 1996
Don H. Catlin; David A. Cowan; R. de la Torre; M. Donike; D. Fraisse; H. Oftebro; Caroline K. Hatton; Borislav Starcevic; Michel Becchi; X. de la Torre; H. Norli; H. Geyer; C. J. Walker
Six laboratories in six countries collaborated to investigate the analytical method for estimating the testosterone to epitestosterone ratio (T/E) in urine by gas chromatography/mass spectrometry in the context of detecting the application of T as a doping agent in sport. The protocol specified many but not all details of reagents and instrument conditions. The design included the distribution and analysis of four urines with different T/E values, three replicates per value, and one standard. The ranges of mean T/E values for the four urines estimated by peak area (PA) were 0.32-0.42, 0.72-0.94, 0.91-1.14 and 3.19-5.48. The analyses of variance for these data and for the peak height (PH) data were significant for the laboratory factor (p < 0.0001). In addition there was a significant interaction between the urine factor and the laboratory factor which indicates the complexity of the analysis. T/E calculated using PA was not significantly different from that using PH. For within-laboratory precision all values for PH and PA were < 8.3%, and for between-laboratory precision all values were < 11.7% except for one (20.1%). The data represent a baseline for future experiments designed to elucidate the sources of within-and between-laboratory variance, and to harmonize estimates of T/E.
Steroids | 2002
Don H. Catlin; Benjamin Z. Leder; Brian D. Ahrens; Caroline K. Hatton; Joel S. Finkelstein
Androstenedione is a steroid hormone sold over-the-counter to individuals who expect that it will enhance strength and athletic performance. Endogenous androstenedione is the immediate precursor of testosterone. To evaluate the metabolism of oral androstenedione, we randomly assigned 37 healthy men to receive 0 (group 1), 100 mg (group 2), or 300 mg (group 3) of androstenedione in a single daily dose for 7 days. Eight-hour urines were collected 1 day before the start of androstenedione, and on days 1 and 7. Using gas chromatography-mass spectrometry, we measured excretion rates of glucuronide-conjugated epitestosterone, its putative precursor (E-precursor), and metabolites (EM-1 and EM-2), and we evaluated possible markers of androstenedione administration. Day 1 and 7 rates were not different: the means were averaged. The means (microg/h) for groups 1, 2, and 3, respectively were, for epitestosterone 2.27, 7.74, and 18.0; for E-precursor, 2.9, 2.0, and 1.5; for EM-1/E-precursor 0.31, 1.25, and 2.88; for EM-2/E-precursor 0.14, 0.15, and 1.15; for testosterone/epitestosterone (T/E) 1.1, 3.5, and 3.2. Epitestosterone, EM-1, and EM-2 excretion was greater in groups 2 and 3 versus group 1 (0.0001 < P < 0.03), as were EM-1/E-precursor, EM-2/E-precursor, and T/E. E-precursor excretion was lower in groups 2 (P = 0.08) and 3 (P = 0.047) versus group 1. Androstenedione increases excretion of epitestosterone and its two metabolites, while decreasing that of its precursor. Elevated ratios of EM-1- and EM-2/E-precursor, and the presence of 6alpha-hydroxyandrostenedione are androstenedione administration markers.
Journal of Chromatography B: Biomedical Sciences and Applications | 1997
Rodrigue Aguilera; Michel Becchi; L. Mateus; M.A. Popot; Y. Bonnaire; Hervé Casabianca; Caroline K. Hatton
A gas chromatography-combustion-isotope ratio mass spectrometry method for confirmation of hydrocortisone abuse in horseracing and equine sports is proposed. Urinary hydrocortisone was converted to a bismethylenedioxy derivative which presents good gas chromatographic properties and brings an extra carbon contribution of only two carbon atoms. Synthetic hydrocortisone has a different 13C abundance from that of natural urinary horse hydrocortisone and the difference is significant, therefore exogenous and endogenous hydrocortisone can be distinguished.
Physical Medicine and Rehabilitation Clinics of North America | 2014
Caroline K. Hatton; Gary A. Green; Peter J. Ambrose
To help clinicians understand the risks associated with performance-enhancing drugs, this overview covers prohibited lists of substances and methods, therapeutic use exemptions, the legitimate indications and adverse effects, including for megadose and polypharmacy doping of stimulants, anabolic steroids, erythropoiesis-stimulating agents, and growth hormone and ways in which physicians or patients risk committing anti-doping rule violations inadvertently.
Archive | 2009
Don H. Catlin; Caroline K. Hatton
Ever since the beginning of recorded time, there has been evidence that men experiment with performance enhancement. In ancient times, medicinal plants were used for doping. Now sport is coping with drugs developed with recombinant-DNA technology and genetic manipulation is being discussed.
Rapid Communications in Mass Spectrometry | 2004
Don H. Catlin; Michael H. Sekera; Brian D. Ahrens; Borislav Starcevic; Yu-Chen Chang; Caroline K. Hatton
JAMA | 2000
Don H. Catlin; Benjamin Z. Leder; Brian D. Ahrens; Borislav Starcevic; Caroline K. Hatton; Gary A. Green; Joel S. Finkelstein
Clinical Chemistry | 1997
Don H. Catlin; Caroline K. Hatton; Sanja H. Starcevic