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3.
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.

4.
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
5.
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
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: 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
9.
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
10.
Scand J Med Sci Sports ; 16(1): 41-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16430680

RESUMO

The purpose of this study was to analyze the composition of 103 dietary supplements bought on the internet. The supplements were dispatched in four different categories according to their announced contents [creatine, prohormones, "mental enhancers" and branched chain amino acids (BCAA)]. All the supplements were screened for the presence of stimulants and main anabolic steroids parent compounds. At the same time, the research was focused on the precursors and metabolites of testosterone and nandrolone. The study pointed out three products containing an anabolic steroid, metandienone, in a very high amount. The ingestion of such products induced a high quantity of metandienone metabolites in urines that would be considered as a positive antidoping test. The results have also shown that one creatine product and three "mental enhancers" contained traces of hormones or prohormones not claimed on the labels and 14 prohormone products contained substances other than those indicated by the manufacturer. The oral intake of the creatine product revealed the presence of the two main nandrolone metabolites (19-norandrosterone and 19-noretiocholanolone) in urine.


Assuntos
Anabolizantes/análise , Estimulantes do Sistema Nervoso Central/análise , Suplementos Nutricionais/análise , Dopagem Esportivo , Metandrostenolona/análise , Medicamentos sem Prescrição/química , Suplementos Nutricionais/provisão & distribuição , Contaminação de Medicamentos , Rotulagem de Medicamentos , Humanos , Internet , Medicamentos sem Prescrição/provisão & distribuição , Projetos Piloto , Esportes , Esteroides
11.
Int J Sport Nutr Exerc Metab ; 11(2): 258-63, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11402257

RESUMO

We report the findings of the analysis of 75 different nutritional supplements bought through the internet. Seven products (all from the class of prohormones) contained other hormone substances than indicated on the labels, and two further products contained ephedrine and caffeine without a clear indication on the labels.


Assuntos
Suplementos Nutricionais/análise , Dopagem Esportivo , Rotulagem de Medicamentos/normas , Cafeína/isolamento & purificação , Contaminação de Medicamentos , Efedrina/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Humanos
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