Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Physiol Rep ; 11(19): e15834, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37828664

RESUMO

Hemoglobin concentration ([Hb]) is used for the clinical diagnosis of anemia, and in sports as a marker of blood doping. [Hb] is however subject to significant variations mainly due to shifts in plasma volume (PV). This study proposes a newly developed model able to accurately predict total hemoglobin mass (Hbmass) and PV from a single complete blood count (CBC) and anthropometric variables in healthy subject. Seven hundred and sixty-nine CBC coupled to measures of Hbmass and PV using a CO-rebreathing method were used with a machine learning tool to calculate an estimation model. The predictive model resulted in a root mean square error of 33.2 g and 35.6 g for Hbmass, and 179 mL and 244 mL for PV, in women and men, respectively. Measured and predicted data were significantly correlated (p < 0.001) with a coefficient of determination (R2 ) ranging from 0.76 to 0.90 for Hbmass and PV, in both women and men. The Bland-Altman bias was on average 0.23 for Hbmass and 4.15 for PV. We herewith present a model with a robust prediction potential for Hbmass and PV. Such model would be relevant in providing complementary data in contexts such as the epidemiology of anemia or the individual monitoring of [Hb] in anti-doping.


Assuntos
Anemia , Dopagem Esportivo , Masculino , Humanos , Feminino , Volume Plasmático , Hemoglobinas/análise , Antropometria
3.
Talanta ; 144: 196-203, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26452810

RESUMO

A headspace-gas chromatography-tandem mass spectrometry (HS-GC-MS/MS) method for the trace measurement of perfluorocarbon compounds (PFCs) in blood was developed. Due to oxygen carrying capabilities of PFCs, application to doping and sports misuse is speculated. This study was therefore extended to perform validation methods for F-tert-butylcyclohexane (Oxycyte(®)), perfluoro(methyldecalin) (PFMD) and perfluorodecalin (PFD). The limit of detection of these compounds was established and found to be 1.2 µg/mL blood for F-tert-butylcyclohexane, 4.9 µg/mL blood for PFMD and 9.6 µg/mL blood for PFD. The limit of quantification was assumed to be 12 µg/mL blood (F-tert-butylcyclohexane), 48 µg/mL blood (PFMD) and 96 µg/mL blood (PFD). HS-GC-MS/MS technique allows detection from 1000 to 10,000 times lower than the estimated required dose to ensure a biological effect for the investigated PFCs. Thus, this technique could be used to identify a PFC misuse several hours, maybe days, after the injection or the sporting event. Clinical trials with those compounds are still required to evaluate the validation parameters with the calculated estimations.


Assuntos
Cicloexanos/sangue , Fluorocarbonos/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
5.
Biol Sport ; 31(2): 85-93, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24899771

RESUMO

The final tournament of the UEFA European Football Championship is one of the top sporting events in the world, and a high-profile event of this kind requires a well-planned and well-executed anti-doping programme to ensure the integrity of results in the competition. UEFA EURO 2012 presented a unique logistical challenge, with the tournament spread across two countries, both covering a large geographical area. This paper discusses the planning and delivery of both the pre tournament out-of-competition (OOC) testing programme and the in-competition (IC) programme, as well as reviewing the activities of doping control officers (DCOs), the whereabouts programme and assessing the sample collection and transport process. The analytical approach applied is also discussed, along with an overview of the distribution of T/E ratios and blood parameters.

6.
Rev Med Suisse ; 9(393): 1414-7, 2013 Jul 17.
Artigo em Francês | MEDLINE | ID: mdl-23971326

RESUMO

This article reviews the evidence-based ergogenic potential adverse effects of the most common products in use by recreational and elite athletes today. This is an aggressively marketed and controversial area of sports medicine wordwide. It is therefore important for the scientific societies, clinicians, dieticians sports federations to be well versed in the more popular supplements and drugs in order to have an important role in information and prevention attitudes that can lead to health risks or addictions!


Assuntos
Atletas , Dopagem Esportivo , Medicina Esportiva , Prática Clínica Baseada em Evidências/métodos , Humanos , Esportes/normas
7.
J Steroid Biochem Mol Biol ; 138: 222-35, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23796409

RESUMO

The screening of testosterone (T) misuse for doping control is based on the urinary steroid profile, including T, its precursors and metabolites. Modifications of individual levels and ratio between those metabolites are indicators of T misuse. In the context of screening analysis, the most discriminant criterion known to date is based on the T glucuronide (TG) to epitestosterone glucuronide (EG) ratio (TG/EG). Following the World Anti-Doping Agency (WADA) recommendations, there is suspicion of T misuse when the ratio reaches 4 or beyond. While this marker remains very sensitive and specific, it suffers from large inter-individual variability, with important influence of enzyme polymorphisms. Moreover, use of low dose or topical administration forms makes the screening of endogenous steroids difficult while the detection window no longer suits the doping habit. As reference limits are estimated on the basis of population studies, which encompass inter-individual and inter-ethnic variability, new strategies including individual threshold monitoring and alternative biomarkers were proposed to detect T misuse. The purpose of this study was to evaluate the potential of ultra-high pressure liquid chromatography (UHPLC) coupled with a new generation high resolution quadrupole time-of-flight mass spectrometer (QTOF-MS) to investigate the steroid metabolism after transdermal and oral T administration. An approach was developed to quantify 12 targeted urinary steroids as direct glucuro- and sulfo-conjugated metabolites, allowing the conservation of the phase II metabolism information, reflecting genetic and environmental influences. The UHPLC-QTOF-MS(E) platform was applied to clinical study samples from 19 healthy male volunteers, having different genotypes for the UGT2B17 enzyme responsible for the glucuroconjugation of T. Based on reference population ranges, none of the traditional markers of T misuse could detect doping after topical administration of T, while the detection window was short after oral TU ingestion. The detection ability of the 12 targeted steroids was thus evaluated by using individual thresholds following both transdermal and oral administration. Other relevant biomarkers and minor metabolites were studied for complementary information to the steroid profile, including sulfoconjugated analytes and hydroxy forms of glucuroconjugated metabolites. While sulfoconjugated steroids may provide helpful screening information for individuals with homozygotous UGT2B17 deletion, hydroxy-glucuroconjugated analytes could enhance the detection window of oral T undecanoate (TU) doping.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Testosterona/administração & dosagem , Testosterona/farmacocinética , Administração Cutânea , Administração Oral , Adulto , Humanos , Masculino , Adulto Jovem
8.
Growth Horm IGF Res ; 23(4): 105-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23608056

RESUMO

OBJECTIVE: The major objective of this study was to investigate the effects of several days of intense exercise on growth hormone (hGH) testing using the World Anti-Doping Agencies hGH isoform differential immunoassays. Additionally the effects of circadian variation and exercise type on the isoform ratios were also investigated. STUDY DESIGN: 15 male athletes performed a simulated nine day cycling stage race. Blood samples were collected twice daily over a period of 15 days (stage race+three days before and after). hGH isoforms were analysed by the official WADA immunoassays (CMZ Assay GmbH). RESULTS: All measured isoform ratios were far below the WADA decision limits for an adverse analytical finding. Changes in the isoform ratios could not be clearly connected to circadian variation, exercise duration or intensity. CONCLUSIONS: The present study demonstrates that the hGH isoform ratios are not significantly affected by exercise or circadian variation. We demonstrated that heavy, long term exercise does not interfere with the decision limits for an adverse analytical finding.


Assuntos
Dopagem Esportivo , Exercício Físico/fisiologia , Hormônio do Crescimento Humano/sangue , Detecção do Abuso de Substâncias/métodos , Adulto , Hormônio do Crescimento Humano/administração & dosagem , Humanos , Imunoensaio , Masculino , Isoformas de Proteínas , Fatores de Tempo
9.
Anal Chim Acta ; 707(1-2): 107-13, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22027126

RESUMO

The anti-diuretic neurohypophysial hormone Vasopressin (Vp) and its synthetic analogue Desmopressin (Dp, 1-desamino-vasopressin) have received considerable attention from doping control authorities due to their impact on physiological blood parameters. Accordingly, the illicit use of Desmopressin in elite sport is sanctioned by the World Anti-Doping Agency (WADA) and the drug is classified as masking agent. Vp and Dp are small (8-9 amino acids) peptides administered orally as well as intranasally. Within the present study a method to determine Dp and Vp in urinary doping control samples by means of liquid chromatography coupled to quadrupole high resolution time-of-flight mass spectrometry was developed. After addition of Lys-Vasopressin as internal standard and efficient sample clean up with a mixed mode solid phase extraction (weak cation exchange), the samples were directly injected into the LC-MS system. The method was validated considering the parameters specificity, linearity, recovery (80-100%), accuracy, robustness, limit of detection/quantification (20/50 pg mL(-1)), precision (inter/intra-day<10%), ion suppression and stability. The analysis of administration study urine samples collected after a single intranasal or oral application of Dp yielded in detection windows for the unchanged target analyte for up to 20 h at concentrations between 50 and 600 pg mL(-1). Endogenous Vp was detected in concentrations of approximately 20-200 pg mL(-1) in spontaneous urine samples obtained from healthy volunteers. The general requirements of the developed method provide the characteristics for an easy transfer to other anti-doping laboratories and support closing another potential gap for cheating athletes.


Assuntos
Desamino Arginina Vasopressina/urina , Dopagem Esportivo , Espectrometria de Massas em Tandem/métodos , Vasopressinas/urina , Administração Intranasal , Administração Oral , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Desamino Arginina Vasopressina/administração & dosagem , Dopagem Esportivo/prevenção & controle , Humanos , Masculino , Espectrometria de Massas/métodos , Espectrometria de Massas/normas , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/normas , Vasopressinas/administração & dosagem
10.
Int J Lab Hematol ; 33(2): 146-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20718874

RESUMO

INTRODUCTION: With the setting up of the newly Athlete's Biological Passport antidoping programme, novel guidelines have been introduced to guarantee results beyond reproach. We investigated in this context, the effect of storage time on the variables commonly measured for the haematological passport. We also wanted to assess for these variables, the within and between analyzer variations. METHODS: Blood samples were obtained from top level male professional cyclists (27 samples for the first part of the study and 102 for the second part) taking part to major stage races. After collection, they were transported under refrigerated conditions (2 °C < T < 12 °C), delivered to the antidoping laboratory, analysed and then stored at approximately 4 °C to conduct analysis at different time points up to 72 h after delivery. A mixed-model procedure was used to determine the stability of the different variables. RESULTS: As expected haemoglobin concentration was not affected by storage and showed stability for at least 72 h. Under the conditions of our investigation, the reticulocytes percentage showed a much better stability than previous published data (> 48 h) and the technical comparison of the haematology analyzer demonstrated excellent results. CONCLUSION: In conclusion, our data clearly demonstrate that as long as the World Anti-Doping Agency's guidelines are followed rigorously, all blood results reach the quality level required in the antidoping context.


Assuntos
Dopagem Esportivo , Testes Hematológicos/métodos , Atletas , Testes Hematológicos/instrumentação , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes
11.
J Chromatogr A ; 1217(25): 4109-19, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-19939397

RESUMO

For doping control, analyses of samples are generally achieved in two steps: a rapid screening and, in the case of a positive result, a confirmatory analysis. A two-step methodology based on ultra-high-pressure liquid chromatography coupled to a quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) was developed to screen and confirm 103 doping agents from various classes (e.g., beta-blockers, stimulants, diuretics, and narcotics). The screening method was presented in a previous article as part I (i.e., Fast analysis of doping agents in urine by ultra-high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry. Part I: screening analysis). For the confirmatory method, basic, neutral and acidic compounds were extracted by a dedicated solid-phase extraction (SPE) in a 96-well plate format and detected by MS in the tandem mode to obtain precursor and characteristic product ions. The mass accuracy and the elemental composition of precursor and product ions were used for compound identification. After validation including matrix effect determination, the method was considered reliable to confirm suspect results without ambiguity according to the positivity criteria established by the World Anti-Doping Agency (WADA). Moreover, an isocratic method was developed to separate ephedrine from its isomer pseudoephedrine and cathine from phenylpropanolamine in a single run, what allowed their direct quantification in urine.


Assuntos
Anabolizantes/urina , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo/prevenção & controle , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Humanos
12.
Br J Sports Med ; 43(13): 1041-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19549614

RESUMO

BACKGROUND AND OBJECTIVES: The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. METHODS: Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). RESULTS: Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. CONCLUSIONS: The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.


Assuntos
Isótopos de Carbono , Dopagem Esportivo/prevenção & controle , Futebol , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Testosterona , Adolescente , Adulto , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Padrões de Referência , Adulto Jovem
13.
J Chromatogr A ; 1216(20): 4423-33, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19342059

RESUMO

The general strategy to perform anti-doping analyses of urine samples starts with the screening for a wide range of compounds. This step should be fast, generic and able to detect any sample that may contain a prohibited substance while avoiding false negatives and reducing false positive results. The experiments presented in this work were based on ultra-high-pressure liquid chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry. Thanks to the high sensitivity of the method, urine samples could be diluted 2-fold prior to injection. One hundred and three forbidden substances from various classes (such as stimulants, diuretics, narcotics, anti-estrogens) were analysed on a C(18) reversed-phase column in two gradients of 9min (including two 3min equilibration periods) for positive and negative electrospray ionisation and detected in the MS full scan mode. The automatic identification of analytes was based on retention time and mass accuracy, with an automated tool for peak picking. The method was validated according to the International Standard for Laboratories described in the World Anti-Doping Code and was selective enough to comply with the World Anti-Doping Agency recommendations. In addition, the matrix effect on MS response was measured on all investigated analytes spiked in urine samples. The limits of detection ranged from 1 to 500ng/mL, allowing the identification of all tested compounds in urine. When a sample was reported positive during the screening, a fast additional pre-confirmatory step was performed to reduce the number of confirmatory analyses.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Urina/química , Diuréticos/urina , Entorpecentes/urina
14.
Br J Sports Med ; 43(14): 1126-30, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19282302

RESUMO

BACKGROUND AND OBJECTIVES: Urinary steroid profiling is used in doping controls to detect testosterone abuse. A testosterone over epitestosterone (T/E) ratio exceeding 4.0 is considered as suspicious of testosterone administration, irrespectively of individual heterogeneous factors such as the athlete's ethnicity. A deletion polymorphism in the UGT2B17 gene was demonstrated to account for a significant part of the interindividual variability in the T/E between Caucasians and Asians. Here, the variability of urinary steroid profiles was examined in a widely heterogeneous cohort of professional soccer players. METHOD: The steroid profile of 57 Africans, 32 Asians, 50 Caucasians and 32 Hispanics was determined by gas chromatography-mass spectrometry. RESULTS: Significant differences have been observed between all ethnic groups. After estimation of the prevalence of the UGT2B17 deletion/deletion genotype (African: 22%; Asian: 81%; Caucasian: 10%; Hispanic: 7%), ethnic-specific thresholds were developed for a specificity of 99% for the T/E (African: 5.6; Asian: 3.8; Caucasian: 5.7; Hispanic: 5.8). Finally, another polymorphism could be hypothesised in Asians based on specific concentration ratio of 5alpha-/5beta-androstane-3alpha,17beta-diol in urine. CONCLUSION: These results demonstrate that a unique and non-specific threshold to evidence testosterone misuse is not fit for purpose. An athlete's endocrinological passport consisting of a longitudinal follow-up together with the ethnicity and/or the genotype would strongly enhance the detection of testosterone abuse. Finally, additional genotyping studies should be undertaken to determine whether the remaining unexplained disparities have an environmental or a genetic origin.


Assuntos
Dopagem Esportivo/prevenção & controle , Grupos Raciais/genética , Futebol , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Cromatografia Gasosa-Espectrometria de Massas , Deleção de Genes , Genótipo , Glucuronosiltransferase/genética , Humanos , Masculino , Antígenos de Histocompatibilidade Menor , Polimorfismo Genético/genética , Valores de Referência , Adulto Jovem
16.
Forensic Sci Int Genet ; 1(3-4): 281-2, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19083774

RESUMO

Endogenous and exogenous erythropoietin (EPO) present in urine can be distinguished according to their isoelectric profiles. This methodology requires urine samples to be concentrated about 200 to 1000 times with manipulations that should remove most of the cells occurring in the original sample. In this study, we tried to obtain DNA profiles from 10 ultrafiltered urines (retentates) in order to evaluate whether a formal genetic identification was technically feasible. No nuclear DNA profiles could be established from retentates, despite 34 PCR-cycles amplifications. Contrastingly, mitochondrial DNA (mtDNA) profiles were obtained for 9 out of the 10 retentates. Apart from some particularities, retentate mtDNA profiles were all distinct and matched mtDNA profiles of corresponding reference samples.


Assuntos
DNA/genética , DNA/urina , Dopagem Esportivo , Eritropoetina/urina , Genética Forense/métodos , Impressões Digitais de DNA , DNA Mitocondrial/genética , DNA Mitocondrial/urina , Feminino , Humanos , Masculino , Proteínas Recombinantes , Ultrafiltração
17.
Br J Sports Med ; 40 Suppl 1: i13-5, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799094

RESUMO

BACKGROUND AND OBJECTIVES: Cannabis is on the list of prohibited substances in the practice of sport, although its performance enhancing effect has not yet been proved. Its popularity among the younger generations as a social drug puts cannabis at the top of the list of compounds detected by the anti-doping laboratories accredited by the World Anti-Doping Agency worldwide. The management of the results of urine analysis is quite difficult for the medical and disciplinary committees not only because of the social use of the substance, but also because of the interpretation of the analytical data from urine samples. This paper gives an overview of what is presently known about cannabis in relation with the practice of sport. METHODS: Review of literature on the cannabis and exercise, its effect in the body, and the problems with interpretation of results when it is detected in urine. RESULTS: The paper outlines the major effects of cannabis in the context of its social use and its use for sport activities. The difficulties in the interpretation of urine sample analysis results because of the protracted excretion time of the main metabolite, long after the intake, are described. CONCLUSIONS: There is an urgent need for sport authorities to take measures necessary to avoid players misusing cannabis.


Assuntos
Cannabis/efeitos adversos , Dopagem Esportivo/prevenção & controle , Esportes/legislação & jurisprudência , Comportamento Competitivo , Dopagem Esportivo/legislação & jurisprudência , Humanos , Esportes/fisiologia , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/urina , Urinálise
18.
Br J Sports Med ; 40 Suppl 1: i16-20, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799095

RESUMO

BACKGROUND AND OBJECTIVES: Central nervous system (CNS) stimulants may be used to reduce tiredness and increase alertness, competitiveness, and aggression. They are more likely to be used in competition but may be used during training to increase the intensity of the training session. There are several potential dangers involving their misuse in contact sports. This paper reviews the three main CNS stimulants, ephedrine, amfetamine, and cocaine, in relation to misuse in sport. METHODS: Description of the pharmacology, actions, and side effects of amfetamine, cocaine, and ephedrine. RESULTS: CNS stimulants have psychotropic effects that may be perceived to be ergogenic. Some are prescription drugs, such as Ephedra alkaloids, and there are issues regarding their appropriate therapeutic use. Recently attention has been given to their widespread use by athletes, despite the lack of evidence regarding any ergogenic or real performance benefit, and their potentially serious side effects. Recreational drugs, some of which are illegal (cocaine, amfetamines), are commonly used by athletes and cause potential ergolytic effects. Overall, these drugs are important for their frequent use and mention in anti-doping laboratories statistics and the media, and their potentially serious adverse effects. CONCLUSIONS: Doping with CNS stimulants is a real public health problem and all sports authorities should participate in its prevention. Dissemination of information is essential to prevent doping in sport and to provide alternatives. Adequate training and education in this domain should be introduced.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Dopagem Esportivo/prevenção & controle , Esportes , Anfetamina/efeitos adversos , Anfetamina/farmacologia , Estimulantes do Sistema Nervoso Central/efeitos adversos , Cocaína/efeitos adversos , Cocaína/farmacologia , Inibidores da Captação de Dopamina/efeitos adversos , Efedrina/efeitos adversos , Efedrina/farmacologia , Humanos
20.
Br J Sports Med ; 40 Suppl 1: i21-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799097

RESUMO

BACKGROUND AND OBJECTIVES: Anabolic steroids are synthetic derivatives of testosterone, modified to enhance its anabolic actions (promotion of protein synthesis and muscle growth). They have numerous side effects, and are on the International Olympic Committee's list of banned substances. Gas chromatography-mass spectrometry allows identification and characterisation of steroids and their metabolites in the urine but may not distinguish between pharmaceutical and natural testosterone. Indirect methods to detect doping include determination of the testosterone/epitestosterone glucuronide ratio with suitable cut-off values. Direct evidence may be obtained with a method based on the determination of the carbon isotope ratio of the urinary steroids. This paper aims to give an overview of the use of anabolic-androgenic steroids in sport and methods used in anti-doping laboratories for their detection in urine, with special emphasis on doping with testosterone. METHODS: Review of the recent literature of anabolic steroid testing, athletic use, and adverse effects of anabolic-androgenic steroids. RESULTS: Procedures used for detection of doping with endogenous steroids are outlined. The World Anti-Doping Agency provided a guide in August 2004 to ensure that laboratories can report, in a uniform way, the presence of abnormal profiles of urinary steroids resulting from the administration of testosterone or its precursors, androstenediol, androstenedione, dehydroepiandrosterone or a testosterone metabolite, dihydrotestosterone, or a masking agent, epitestosterone. CONCLUSIONS: Technology developed for detection of testosterone in urine samples appears suitable when the substance has been administered intramuscularly. Oral administration leads to rapid pharmacokinetics, so urine samples need to be collected in the initial hours after intake. Thus there is a need to find specific biomarkers in urine or plasma to enable detection of long term oral administration of testosterone.


Assuntos
Androgênios/administração & dosagem , Dopagem Esportivo/prevenção & controle , Detecção do Abuso de Substâncias/métodos , Testosterona/administração & dosagem , Administração Oral , Androgênios/sangue , Androgênios/urina , Biomarcadores/sangue , Biomarcadores/urina , Humanos , Injeções Intramusculares , Testosterona/sangue , Testosterona/urina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...