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1.
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.

2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
Br J Sports Med ; 40 Suppl 1: i35-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799101

RESUMO

BACKGROUND AND OBJECTIVES: Recombinant human growth hormone (rhGH) has been on the list of forbidden substances since availability of its recombinant form improved in the early 1990s. Although its effectiveness in enhancing physical performance is still unproved, the compound is likely used for its potential anabolic effect on the muscle growth, and also in combination with other products (androgens, erythropoietin, etc.). The degree of similarity between the endogenous and the recombinant forms, the pulsatile secretion and marked interindividual variability makes detection of doping difficult. Two approaches proposed to overcome this problem are: the indirect method, which measures a combination of several factors in the biological cascade affected by administration of GH; and the direct method, which measures the difference between the circulating and the recombinant (represented by the unique 22 kD molecule) forms of GH. This article gives an overview of what is presently known about hGH in relation to sport. The available methods of detection are also evaluated. METHODS: Review of the literature on GH in relation to exercise, and its adverse effects and methods of detection when used for doping. RESULTS AND CONCLUSION: The main effects of exercise on hGH production and the use and effects of rhGH in athletes are discussed. Difficulties encountered by laboratories to prove misuse of this substance by both indirect and direct analyses are emphasised. The direct method currently seems to have the best reliability, even though the time window of detection is too short. hGH doping is a major challenge in the fight against doping. The effect of exercise on hGH and its short half-life are still presenting difficulties during doping analysis. To date the most promising method appears to be the direct approach utilising immunoassays.


Assuntos
Dopagem Esportivo/prevenção & controle , Hormônio do Crescimento Humano/farmacologia , Esportes/fisiologia , Detecção do Abuso de Substâncias/métodos , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/urina , Humanos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/urina
9.
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
10.
Br J Sports Med ; 40 Suppl 1: i3-i12, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799099

RESUMO

BACKGROUND AND OBJECTIVES: FIFA's anti-doping strategy relies on education and prevention. A worldwide network of physicians guarantees doping control procedures that are straightforward and leave no place for cheating. FIFA actively acknowledges its responsibility to protect players from harm and ensure equal chances for all competitors by stringent doping control regulations, data collection of positive samples, support of research, and collaboration with other organisations. This article aims to outline FIFA's approach to doping in football. METHOD: Description of FIFA's doping control regulations and procedures, statistical analysis of FIFA database on doping control, and comparison with data obtained by WADA accredited laboratories as for 2004. RESULTS: Data on positive doping samples per substance and confederation/nation documented at the FIFA medical office from 1994 to 2005 are provided. According to the FIFA database, the incidence of positive cases over the past 11 years was 0.12%, with about 0.42% in 2004 (based on the assumption of 20,750 samples per year) and 0.37% in 2005. Especially important in this regard is the extremely low incidence of the true performance enhancing drugs such as anabolic steroids and stimulants. However, there is a need for more consistent data collection and cross checks among international anti-doping agencies as well as for further studies on specific substances, methods, and procedures. With regard to general health impairments in players, FIFA suggests that principles of occupational medicine should be considered and treatment with banned substances for purely medical reasons should be permitted to enable players to carry out their profession. At the same time, a firm stand has to be taken against suppression of symptoms by medication with the aim of meeting the ever increasing demands on football players. CONCLUSION: Incidence of doping in football seems to be low, but much closer collaboration and further investigation is needed with regard to banned substances, detection methods, and data collection worldwide.


Assuntos
Dopagem Esportivo/legislação & jurisprudência , Futebol/legislação & jurisprudência , Dopagem Esportivo/prevenção & controle , Dopagem Esportivo/estatística & dados numéricos , Política de Saúde/legislação & jurisprudência , Humanos , Agências Internacionais/legislação & jurisprudência , Futebol/estatística & dados numéricos , Detecção do Abuso de Substâncias/legislação & jurisprudência , Detecção do Abuso de Substâncias/métodos
11.
Br J Sports Med ; 40 Suppl 1: i30-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799100

RESUMO

OBJECTIVE AND METHOD: To outline the direct and indirect approaches in the fight against blood doping in sports, the different strategies that have been used and are currently being used to fight efficiently against blood doping are presented and discussed. RESULTS AND CONCLUSIONS: The paper outlines the different approaches and diagnostic tools that some federations have to identify and target sports people demonstrating abnormal blood profiles. Originally blood tests were introduced for medical reasons and for limiting misuse of recombinant human erythropoietin (rHuEPO). In this way it became possible to prevent athletes with haematocrit levels well above normal, and potentially dangerous for their health, competing in sport. Today, with nearly a decade of blood testing experience, sports authorities should be familiar with some of the limitations and specially the ability of blood tests performed prior to competitions to fight efficiently against the misuse of rHuEPO, blood transfusion, and artificial haemoglobin.


Assuntos
Dopagem Esportivo/prevenção & controle , Eritropoetina/sangue , Esportes , Detecção do Abuso de Substâncias/métodos , Transfusão de Sangue , Eritropoetina/farmacologia , Humanos , Proteínas Recombinantes
12.
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
13.
J Chromatogr A ; 926(1): 87-95, 2001 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-11554422

RESUMO

In this study, we report on the development of a method to confirm simultaneously nine of the most commonly abused synthetic corticosteroids in urine based on liquid chromatography-electrospray ionisation mass spectrometry. A considerable simplified sample preparation procedure, including liquid-liquid phase extraction with Extrelut-NT3 columns, provided both excellent sample purification and high overall recoveries. Complete HPLC separations were obtained on a reversed-phase column with 1 mM ammonium acetate-acetonitrile (60:40, v/v) as mobile phase. Mass spectral acquisition was done in the negative ion, and selected ion monitoring modes to identify the drugs with at least three characteristic ions. Detection limits were determined at < or =1 ng/ml and the confirmation limits at 1 to 5 ng/ml.


Assuntos
Corticosteroides/urina , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Sensibilidade e Especificidade
14.
Forensic Sci Int ; 122(2-3): 130-5, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11672966

RESUMO

Nandrolone (19-nortestosterone) is a widely used anabolic steroid in sports where strength plays an essential role. Once nandrolone has been metabolised, two major metabolites are excreted in urine, 19-norandrosterone (NA) and 19-noretiocholanolone (NE). In 1997, in France, quite a few sportsmen had concentrations of 19-norandrosterone very close to the IOC cut off limit (2ng/ml). At that time, a debate took place about the capability of the human male body to produce by itself these metabolites without any intake of nandrolone or related compounds. The International Football Federation (FIFA) was very concerned with this problematic, especially because the World Cup was about to start in France. In this respect, a statistical study was held with all football players from the first and second divisions of the Swiss Football National League. All players gave a urine sample after effort and around 6% of them showed traces of 19-norandrosterone. These results were compared with amateur football players (control group) and around 6% of them had very small amounts of 19-norandrosterone and/or 19-noretiocholanolone in urine after effort, whereas none of them had detectable traces of one or the other metabolite before effort. The origin of these compounds in urine after a strenuous physical activity is still unknown, but three hypotheses can be put forward. First, an endogenous production of nandrolone metabolites takes place. Second, nandrolone metabolites are released from the fatty tissues after an intake of nandrolone, some related compounds or some contaminated nutritive supplements. Finally, the sportsmen may have taken something during or just before the football game.


Assuntos
Anabolizantes/metabolismo , Nandrolona/metabolismo , Esforço Físico , Futebol/fisiologia , Adulto , Anabolizantes/urina , Teorema de Bayes , Estudos de Casos e Controles , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Nandrolona/urina
15.
Br J Sports Med ; 38(6): 704-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15562163

RESUMO

BACKGROUND: An international, longitudinal medical follow up examination of male professional road cyclists revealed excessively elevated serum ferritin levels. OBJECTIVE: To evaluate the importance of elevated ferritin values among professional cyclists, their relationship with age and nationality, and their evolution over 3 years. METHODS: Over 1000 serum ferritin values were collected. Other parameters were included in order to exclude conditions which might have increased ferritin levels without changing body iron stores. RESULTS: In 1999, over 45% of riders displayed ferritin values above 300 ng/ml and one fourth levels over 500 ng/ml. These percentages had decreased to 27% and 9%, respectively, 3 years later, while the overall average, which was above the normal limits in 1999, had decreased by 33% in 3 years. Older cyclists had higher ferritin values than younger cyclists. There was also a relationship between ferritin levels and the nationality of the cyclists. Analysis of 714 riders in 2000 and 2002 showed only a slight and insignificant decrease in the mean ferritin value although those with initially elevated iron stores had a much greater decrease. CONCLUSION: Professional road cyclists used excessive iron supplementation leading to high serum ferritin levels correlating with increased body iron stores. Although the situation progressively improved over 3 years, it remains worrying as increased body iron stores are related to health complications. Therefore, prevention in addition to the fight against doping should be a main goal of the UCI. Aggressive therapy for athletes with excessive ferritin values should be carried out at or before the end of their careers.


Assuntos
Ciclismo/fisiologia , Ferritinas/sangue , Sobrecarga de Ferro/epidemiologia , Adulto , Distribuição por Idade , Suplementos Nutricionais/efeitos adversos , Seguimentos , Humanos , Ferro/efeitos adversos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/etiologia , Masculino
16.
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
17.
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
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