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1.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34648228

ABSTRACT

The testing strategy for the detection of testosterone (T) or T-prohormones is based on the longitudinal evaluation of urinary steroid concentrations accompanied by subsequent isotope ratio mass spectrometry (IRMS)-based confirmation of samples showing atypical concentrations or concentration ratios. In recent years, the IRMS methodology focussed more and more on T itself and on the metabolites of T, 5α- and 5ß-androstanediol. These target analytes showed the best sensitivity and retrospectivity, but their use has occasionally been challenging due to their comparably low urinary concentrations. Conversely, the carbon isotope ratios (CIR) of the main urinary metabolites of T, androsterone (A) and etiocholanolone (EITO), can readily be measured even from low urine volumes; those however, commonly offer a lower sensitivity and shorter retrospectivity in uncovering T misuse. Within this study, the CIRs of A and ETIO were combined with their urinary concentrations, resulting in a single parameter referred to as 'difference from weighted mean' (DWM). Both glucuronidated and sulfated steroids were investigated, encompassing a reference population (n = 110), longitudinal studies on three individuals, influence of ethanol in two individuals, and re-analysis of several administration studies including T, dihydrotestosterone, androstenedione, epiandrosterone, dehydroepiandrosterone, and T-gel. Especially DWM calculated for the sulfoconjugated steroids significantly prolonged the detection time of steroid hormone administrations when individual reference ranges were applied. Administration studies employing T encompassing CIR common for Europe (-23.8‰ and -24.4‰) were investigated and, even though for a significantly shorter time period and less pronounced, DWM could demonstrate the exogenous source of T metabolites.


Subject(s)
Androsterone/analysis , Etiocholanolone/analysis , Testosterone Congeners/analysis , Testosterone/analysis , Androsterone/urine , Carbon Isotopes , Doping in Sports/prevention & control , Ethanol/administration & dosage , Ethanol/pharmacology , Etiocholanolone/urine , Female , Humans , Longitudinal Studies , Male , Mass Spectrometry/methods , Middle Aged , Substance Abuse Detection/methods , Testosterone/urine , Testosterone Congeners/urine
2.
Drug Test Anal ; 13(11-12): 1915-1920, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34378339

ABSTRACT

Little information on the human metabolism and urinary elimination of hydrafinil (9-fluorenol) exists. In order to support preventive anti-doping activities concerning compounds such as hydrafinil, a pilot elimination study was conducted with three healthy male volunteers receiving a single oral dose of 50 mg of hydrafinil. Urine samples were collected prior to and up to 72-h post-administration and were subjected to both gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, which allowed for the identification of the intact drug as well as Phase I and Phase II metabolites, primarily hydroxylated and/or glucuronidated or sulfo-conjugated hydrafinil. The identity of these metabolites was corroborated by high-resolution/high-accuracy tandem mass spectrometry, and the applicability of routine doping control workflows for the detection of hydrafinil and its main metabolites was assessed. Therefore, two findings of hydrafinil and its metabolites were recorded, which concerned out-of-competition doping control samples and, hence, were not pursued with confirmatory analyses. Yet, the initial testing procedure results indicate that hydrafinil might require consideration in sports drug testing programs to ensure its detection, if classified as prohibited by the World Anti-Doping Agency (WADA).


Subject(s)
Doping in Sports/prevention & control , Mass Spectrometry/methods , Substance Abuse Detection/methods , Chromatography, Liquid/methods , Gas Chromatography-Mass Spectrometry/methods , Humans , Male
3.
Int J Sports Med ; 42(10): 863-878, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34049412

ABSTRACT

For decades, the class of anabolic androgenic steroids has represented the most frequently detected doping agents in athletes' urine samples. Roughly 50% of all adverse analytical findings per year can be attributed to anabolic androgenic steroids, of which about 2/3 are synthetic exogenous steroids, where a qualitative analytical approach is sufficient for routine doping controls. For the remaining 1/3 of findings, caused by endogenous steroid-derived analytical test results, a more sophisticated quantitative approach is required, as their sheer presence in urine cannot be directly linked to an illicit administration. Here, the determination of urinary concentrations and concentration ratios proved to be a suitable tool to identify abnormal steroid profiles. Due to the large inter-individual variability of both concentrations and ratios, population-based thresholds demonstrated to be of limited practicability, leading to the introduction of the steroidal module of the Athlete Biological Passport. The passport enabled the generation of athlete-specific individual reference ranges for steroid profile parameters. Besides an increase in sensitivity, several other aspects like sample substitution or numerous confounding factors affecting the steroid profile are addressed by the Athlete Biological Passport-based approach. This narrative review provides a comprehensive overview on current prospects, supporting professionals in sports drug testing and steroid physiology.


Subject(s)
Doping in Sports/prevention & control , Steroids/analysis , Substance Abuse Detection , Athletes , Confounding Factors, Epidemiologic , Humans , Reference Values
4.
Drug Test Anal ; 2(11-12): 637-42, 2010.
Article in English | MEDLINE | ID: mdl-21204295

ABSTRACT

The testosterone/epitestosterone (T/E) ratio was implemented as an indirect parameter for the detection of testosterone administration with an empirically established threshold value at T/E = 6. In 2005, the T/E reporting threshold was lowered from six to four. Between 2005 and 2009, 63 510 doping control urine samples were analyzed in the Cologne laboratory. A total of 1442 specimens (2.3%) showed a T/E > 4; 80 (5.5%) of which were tested positive by means of isotope ratio mass spectrometry (IRMS); and most of which (68) originated from strength sport disciplines. Specimens of high T/E ratio showed a much higher probability for being confirmed to contain exogenous testosterone using IRMS analysis than samples of low T/E values. Considering the small number of adverse analytical findings triggered by lowering the T/E reporting threshold (978 urine specimens with T/E ratios between 4 and 6 yielded only 4 (0.4%) positive IRMS findings) and the known limitations of the T/E ratio as discriminating parameter (UGT2B17 polymorphism), the currently mandatory approach shows only marginal overall efficiency. A more effective tool for the detection of the misuse of testosterone would be the implementation of individual reference ranges. Until athlete steroidal passports are available, it is suggested to exceed the threshold level for T/E from 4 to 6 and perform obligatory IRMS analysis for specimens showing T/E > 6. Further conditions triggering IRMS analysis could be suppressed luteinizing hormone (LH) values in males and disproportionate changes of relevant parameters in individual profiles evidently not resulting from ethanol consumption.


Subject(s)
Doping in Sports , Epitestosterone/urine , Substance Abuse Detection/trends , Testosterone/urine , Female , Humans , Male , Substance Abuse Detection/methods
5.
Drug Test Anal ; 1(11-12): 505-10, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20355165

ABSTRACT

According to the regulations of the World Anti-Doping Agency (WADA), the use of cannabinoids is forbidden in competition. In doping controls, the detection of cannabinoid misuse is based on the analysis of the non-psychoactive metabolite 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (carboxy-THC). The determination of values greater than 15 ng/mL in urine represents an adverse analytical finding; however, no accurate prediction of the time of application is possible as the half-life of carboxy-THC ranges between three and four days. Consequently the detection of carboxy-THC in doping control urine samples collected in competition might also result from cannabis use in out-of-competition periods. The analysis of the glucuronide of the pharmacologically active delta 9-tetrahydrocannabinol (THC-gluc) may represent a complementary indicator for the detection of cannabis misuse in competition.An assay for the determination of THC-gluc in human urine was established. The sample preparation consisted of liquid-liquid extraction of urine specimens, and extracts were analysed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Authentic doping-control urine samples as well as specimens obtained from a controlled smoking study were analysed and assay characteristics such as specificity, detection limit (0.1 ng/mL), precision (>90%), recovery ( approximately 80%), and extraction efficiency (90%) were determined.


Subject(s)
Doping in Sports , Dronabinol/analogs & derivatives , Dronabinol/pharmacokinetics , Glucuronides/urine , Marijuana Smoking/urine , Substance Abuse Detection/methods , Chromatography, Liquid/methods , Dronabinol/urine , Humans , Sensitivity and Specificity , Tandem Mass Spectrometry/methods , Time Factors
6.
Rapid Commun Mass Spectrom ; 20(12): 1954-62, 2006.
Article in English | MEDLINE | ID: mdl-16715475

ABSTRACT

Anastrozole (2,2'-[5-(1H-1,2,4-triazol-1-ylmethyl)-1.3-phenylene]bis(2-methylpropionitrile)) and exemestane (6-methylenandrostan-1,4-diene-3,17-dione) are therapeutically used to treat hormone-sensitive breast cancer in postmenopausal women. For doping purposes they may be used to counteract adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase plasma testosterone concentrations. Excretion study urine samples and spot urine samples from women suffering from metastatic breast cancer, being treated with anastrozole or exemestane, were collected and analyzed to develop/optimize a detection system for anastrozole and exemestane to allow the identification of athletes who do not comply with the internationally prohibited use of these cancer drugs. The assay was based on liquid-liquid extraction after enzymatic hydrolysis following liquid chromatography/tandem mass spectrometry (LC/MS/MS). Anastrozole, exemestane and its main metabolite (17-dihydroexemestane) were identified in urine by comparison of mass spectra and retention times with respective reference substances. An assay validation for the analysis of anastrozole and exemestane was performed regarding lower limits of detection (anastrozole: 0.02 ng/mL; exemestane: 3.1 ng/mL; dihydroexemestane: 0.5 ng/mL), interday precisions (6.6-11.1%, 4.9-9.1% and 5.6-8.3% for low [10 ng/mL], medium [50 ng/mL] and high [100 ng/mL] concentration) and recoveries (ranged from 85-97%).


Subject(s)
Androstadienes/urine , Antineoplastic Agents, Hormonal/urine , Aromatase Inhibitors/urine , Chromatography, High Pressure Liquid , Nitriles/urine , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , Triazoles/urine , Anastrozole , Androstadienes/pharmacokinetics , Androstadienes/therapeutic use , Antineoplastic Agents, Hormonal/pharmacokinetics , Antineoplastic Agents, Hormonal/therapeutic use , Aromatase Inhibitors/pharmacokinetics , Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Breast Neoplasms/secondary , Female , Humans , Male , Nitriles/pharmacokinetics , Nitriles/therapeutic use , Reproducibility of Results , Substance Abuse Detection/methods , Triazoles/pharmacokinetics , Triazoles/therapeutic use
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