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1.
J Mass Spectrom ; 31(2): 169-76, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8799270

RESUMEN

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.


Asunto(s)
Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos , Testosterona/orina , Adulto , Isótopos de Carbono , Estudios Cruzados , Método Doble Ciego , Epitestosterona/orina , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante
2.
J Mass Spectrom ; 31(4): 397-402, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8799284

RESUMEN

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.


Asunto(s)
Epitestosterona/orina , Testosterona/orina , Análisis de Varianza , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas , Humanos , Indicadores y Reactivos , Laboratorios , Estándares de Referencia , Reproducibilidad de los Resultados
3.
Clin Lab Med ; 7(3): 655-68, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3308301

RESUMEN

Virtually all professional and amateur sporting organizations forbid the use of androgenic anabolic steroids (AAS). The International Olympic Committee, United States Olympic Committee, and more recently the National Collegiate Athletic Association enforce the regulations by conducting urine testing. Over the past 3 years we have conducted about 8000 tests for AAS in urine and discovered several hundred positive cases. AAS when present in urine can be detected by screening and confirmatory tests using gas chromatography-mass spectrometry.


Asunto(s)
Anabolizantes/orina , Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas , Humanos , Monitoreo Fisiológico/métodos , Radioinmunoensayo
4.
Clin Chem ; 43(7): 1280-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9216475

RESUMEN

Over the last decade the number of laboratories accredited by the International Olympic Committee (IOC) has grown to 25. Nearly half of the approximately 90,000 samples tested annually are collected on short notice-the most effective means to deter the use of anabolic androgenic steroids (AAS). The major urinary metabolites of AAS have been characterized and are identified by their chromatographic retention times and full or partial mass spectra. The process of determining if an athlete has used testosterone (T) begins with finding a T to epitestosterone (E) ratio > 6 and continues with a review of the T/E-time profile. For the user who discontinues taking T, the T/E reverts to baseline (typically approximately 1.0). For the extremely rare athlete with a naturally increased T/E ratio, the T/E remains chronically increased. Short-acting formulations of T transiently increase T/E, and E administration lowers it. Among ancillary tests to help discriminate between naturally increased T/E values and those reflecting T use, the most promising is determination of the carbon isotope ratio.


Asunto(s)
Anabolizantes/orina , Doping en los Deportes , Deportes , Detección de Abuso de Sustancias , Testosterona/orina , Epitestosterona/orina , Reacciones Falso Negativas , Humanos , Masculino
5.
J Chromatogr B Biomed Appl ; 687(1): 43-53, 1996 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-9001951

RESUMEN

Two chromatographic methods, reversed-phase liquid chromatography (LC) and immunoaffinity chromatography (IAC), were compared in the preparation of purified testosterone extracts suitable for gas chromatography-combustion/isotope ratio mass spectrometry (GC-C-IRMS) analysis. We have shown previously that GC-C-IRMS is a promising means of detection of testosterone misuse in sport. The two clean-up procedures afford sufficient recovery and adequate purity of testosterone. LC presents several advantages over IAC: access to other urinary steroids, longer column life, no need for special equipment and no antibody preparation. For IAC, the antibodies to testosterone must be selected with care for high affinity and low cross-reactivity. Nevertheless, IAC is of some interest in our experiments, the recovery is slightly better for low concentrations of urinary testosterone and IAC does not induce isotopic discrimination even in overloading experiments. This is the first report on sample preparation by IAC prior to GC-C-IRMS and carbon isotope ratio values for urinary epitestosterone. The carbon isotope ratio test can identify users' urines missed by the testosterone to epitestosterone ratio (T/E > 6) test.


Asunto(s)
Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas/métodos , Detección de Abuso de Sustancias , Testosterona/aislamiento & purificación , Anticuerpos/inmunología , Cromatografía de Afinidad/métodos , Cromatografía Liquida/métodos , Epitestosterona/orina , Humanos , Masculino , Testosterona/inmunología
6.
Clin Chem ; 47(2): 292-300, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11159778

RESUMEN

BACKGROUND: Carbon isotope ratio methods are used in doping control to determine whether urinary steroids are endogenous or pharmaceutical. METHODS: Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) was used to determine the delta(13)C values for 5 beta-androstane-3 alpha,17 beta-diyl diacetate (5 beta A), 5 alpha-androstane-3 alpha,17 beta-diyl diacetate (5 alpha A), and 5 beta-pregnane-3 alpha,20 alpha-diyl diacetate (5 beta P) in a control group of 73 healthy males and 6 athletes with testosterone/epitestosterone ratios (T/E) >6. RESULTS: The within-assay precision SDs for 5 beta A, 5 alpha A, and 5 beta P were +/- 0.27 per thousand, +/- 0.38 per thousand, and +/- 0.28 per thousand, respectively. The between-assay precision SDs ranged from +/- 0.40 per thousand to +/- 0.52 per thousand. The system suitability and batch acceptance scheme is based on SDs. For the control group, the mean delta(13)C (SD) values were -25.69 per thousand (+/- 0.92 per thousand), -26.35 per thousand (+/- 0.68 per thousand), and -24.26 per thousand (+/- 0.70 per thousand), for 5 beta A, 5 alpha A, and 5 beta P, respectively. 5 beta P was greater than 5 beta A and 5 alpha A (P <0.01), and 5 beta A was greater than 5 alpha A (P <0.01). The means - 3 SD were -28.46 per thousand, -28.39 per thousand, and -26.37 per thousand for 5 beta A, 5 alpha A, and 5 beta P, respectively. The maximum difference between 5 beta P and 5 beta A was 3.2 per thousand, and the maximum 5 beta A/5 beta P was 1.13. Three athletes with chronically elevated T/Es had delta(13)C values consistent with testosterone administration and three did not. CONCLUSIONS: This GC-C-IRMS assay of urine diols has low within- and between-assay SDs; therefore, analysis of one urine sample suffices for doping control. The means, SDs, +/-3 SDs, and ranges of delta(13)C values in a control group are established. In comparison, testosterone users have low 5 beta A and 5 alpha A, large differences between 5 beta A or 5 alpha A and 5 beta P, and high 5 beta A/5 beta P and 5 alpha A/5 beta P ratios.


Asunto(s)
Androstano-3,17-diol/orina , Doping en los Deportes , Epitestosterona/orina , Pregnanodiol/orina , Detección de Abuso de Sustancias/métodos , Testosterona/orina , Isótopos de Carbono , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino
7.
J Chromatogr B Biomed Sci Appl ; 702(1-2): 85-91, 1997 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-9449559

RESUMEN

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.


Asunto(s)
Antiinflamatorios/orina , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas/métodos , Caballos/orina , Hidrocortisona/orina , Animales , Antiinflamatorios/química , Isótopos de Carbono , Caballos/metabolismo , Hidrocortisona/química
8.
Clin Chem ; 33(2 Pt 1): 319-27, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2879653

RESUMEN

The equipment, methods, logistics, and results of doping-control analyses for the 1984 Los Angeles Olympic Games are discussed in this article. Within 15 days, 1510 different urine specimens underwent 9440 screening analyses by a combination of gas chromatography, gas chromatography-mass spectrometry, "high-performance" liquid chromatography, and radioimmunoassay. These tests covered more than 200 different drugs and metabolites, including psychomotor stimulants, sympathomimetic amines, central nervous system stimulants, narcotic analgesics, and anabolic steroids. The results are summarized by class of drug. Less than 2% of the samples were found to contain a banned drug.


Asunto(s)
Doping en los Deportes , Preparaciones Farmacéuticas/orina , Antagonistas Adrenérgicos beta/orina , Anabolizantes/orina , California , Fármacos del Sistema Nervioso Central/orina , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Humanos , Narcóticos/orina , Radioinmunoensayo , Simpatomiméticos/orina
9.
J Chromatogr B Biomed Sci Appl ; 727(1-2): 95-105, 1999 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-10360427

RESUMEN

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.


Asunto(s)
Androstano-3,17-diol/orina , Doping en los Deportes , Espectrometría de Masas/métodos , Pregnanodiol/orina , Testosterona/orina , Adulto , Androstano-3,17-diol/análogos & derivados , Biomarcadores , Humanos , Isótopos , Masculino , Persona de Mediana Edad , Estándares de Referencia , Valores de Referencia
10.
JAMA ; 284(20): 2618-21, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11086369

RESUMEN

CONTEXT: Several anabolic steroids are sold over-the-counter (OTC) in the United States, and their production is not regulated by the US Food and Drug Administration. Reports have suggested that use of these supplements can cause positive urine test results for metabolites of the prohibited steroid nandrolone. OBJECTIVES: To assess the content and purity of OTC androstenedione and to determine if androstenedione and 19-norandrostenedione administration causes positive urine test results for 19-norandrosterone, a nandrolone metabolite. DESIGN: Randomized controlled trial of androstenedione, open-label trial of 19-norandrostenedione, and mass spectrometry of androstenedione preparations, conducted between October 1998 and April 2000. SETTING: Outpatient facility of a university hospital. PARTICIPANTS: A total of 41 healthy men aged 20 to 44 years. INTERVENTION: Participants were randomly assigned to receive oral androstenedione, 100 mg/d (n = 13) or 300 mg/d (n = 11) for 7 days, or no androstenedione (n = 13); in addition, 4 patients received 10 microg of 19-norandrostenedione. MAIN OUTCOME MEASURES: Content of OTC androstenedione preparations; level of 19-norandrosterone in urine samples, determined by mass spectrometry, compared among the 3 randomized groups at day 1 and day 7, and among the participants who received 19-norandrostenedione from October 1998 to April 2000. RESULTS: All urine samples from participants treated with androstenedione contained 19-norandrosterone, while no samples from the no-androstenedione group did. Urinary concentrations were averaged for day 1 vs day 7 measurements; mean (SD) 19-norandrosterone concentrations in the 100-mg/d and 300-mg/d groups were 3.8 (2.5) ng/mL and 10.2 (6.9) ng/mL, respectively (P =. 006). The 19-norandrosterone content exceeded the cutoff for reporting positive cases (>2.0 ng/mL) in 20 of 24. The androstenedione preparation used was pure at a sensitivity of 0.1%, but at 0.001% 19-norandrostenedione was found. For the 4 participants to whom 10 microg of 19-norandrostenedione was administered, 19-norandrosterone was found in all urine samples. Of 7 brands of androstenedione analyzed at the 1% level, 1 contained no androstenedione, 1 contained 10 mg of testosterone, and 4 more contained 90% or less of the amount stated on the label. CONCLUSION: Our study suggests that trace contamination of androstenedione with 19-norandrostenedione is sufficient to cause urine test results positive for 19-norandrosterone, the standard marker for nandrolone use. Oral steroid doses as small as 10 microg are absorbed and excreted in urine. Some brands of androstenedione are grossly mislabeled. Careful analysis of androstenedione preparations is recommended in all studies of its biological effects. JAMA. 2000;284:2618-2621.


Asunto(s)
Anabolizantes/metabolismo , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Contaminación de Medicamentos , Estranos/orina , Nandrolona/metabolismo , Medicamentos sin Prescripción , Adulto , Androstenodiona/química , Androstenodiona/farmacología , Suplementos Dietéticos , Humanos , Masculino , Espectrometría de Masas , Detección de Abuso de Sustancias , Estados Unidos , Urinálisis
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