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1.
Rapid Commun Mass Spectrom ; 29(11): 991-9, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26044265

RESUMO

RATIONALE: Potentially performance-enhancing agents, particularly anabolic agents, are advertised and distributed by Internet-based suppliers to a substantial extent. Among these anabolic agents, a substance referred to as LGD-4033 has been made available, comprising the core structure of a class of selective androgen receptor modulators (SARMs). METHODS: In order to provide comprehensive analytical data for doping controls, the substance was obtained and characterized by nuclear magnetic resonance spectroscopy (NMR) and liquid chromatography/electrospray ionization high resolution/high accuracy tandem mass spectrometry (LC/ESI-HRMS). Following the identification of 4-(2-(2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-(trifluoromethyl)benzonitrile, the substance was subjected to in vitro metabolism studies employing human liver microsomes and Cunninghamella elegans (C. elegans) preparations as well as electrochemical metabolism simulations. RESULTS: By means of LC/ESI-HRMS, five main phase-I metabolites were identified as products of liver microsomal preparations including three monohydroxylated and two bishydroxylated species. The two most abundant metabolites (one mono- and one bishydroxylated product) were structurally confirmed by LC/ESI-HRMS and NMR. Comparing the metabolic conversion of 4-(2-(2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-(trifluoromethyl)benzonitrile observed in human liver microsomes with C. elegans and electrochemically derived metabolites, one monohydroxylated product was found to be predominantly formed in all three methodologies. CONCLUSIONS: The implementation of the intact SARM-like compound and its presumed urinary phase-I metabolites into routine doping controls is suggested to expand and complement existing sports drug testing methods.


Assuntos
Anabolizantes/química , Anabolizantes/metabolismo , Androgênios/química , Androgênios/metabolismo , Receptores Androgênicos/metabolismo , Anabolizantes/economia , Cromatografia Líquida , Cunninghamella/efeitos dos fármacos , Cunninghamella/metabolismo , Dopagem Esportivo/economia , Humanos , Internet , Espectroscopia de Ressonância Magnética , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Detecção do Abuso de Substâncias , Espectrometria de Massas em Tandem
4.
Subst Use Misuse ; 49(9): 1201-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24832718

RESUMO

The anti-doping system, under the guidance of WADA, costs at least $228 million per year, mostly to cover the cost of performing about 270,000 doping tests. However, "testing has not proven to be particularly effective in detecting dopers/cheats" (WADA). It is suggested, competitions of doping-endangered disciplines be redesigned. Sports with numerous doping cases should be temporarily excluded from the Olympic program and not be televised. Pecuniary fines should be higher and collection guaranteed by a deferred compensation model. Sports with multiple doping offenses should bear most of the anti-doping costs. Finally, appropriate tenders should guarantee fees of anti-doping laboratories develop more competitively.


Assuntos
Redução de Custos/métodos , Dopagem Esportivo/economia , Detecção do Abuso de Substâncias/economia , Redução de Custos/economia , Humanos , Laboratórios
5.
Br J Sports Med ; 48(10): 807-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24764551

RESUMO

Prominent doping cases in certain sports have recently raised public awareness of doping and reinforced the perception that doping is widespread. Efforts to deal with doping in sport have intensified in recent years, yet the general public believes that the 'cheaters' are ahead of the testers. Therefore, there is an urgent need to change the antidoping strategy. For example, the increase in the number of individual drug tests conducted between 2005 and 2012 was approximately 90 000 and equivalent to an increase of about 50%, yet the number of adverse analytical findings remained broadly the same. There is also a strikingly different prevalence of doping substances and methods in sports such as a 0.03% prevalence of anabolic steroids in football compared to 0.4% in the overall WADA statistics. Future efforts in the fight against doping should therefore be more heavily based on preventative strategies such as education and on the analysis of data and forensic intelligence and also on the experiences of relevant stakeholders such as the national antidoping organisations, the laboratories, athletes or team physicians and related biomedical support staff. This strategy is essential to instigate the change needed to more effectively fight doping in sport.


Assuntos
Dopagem Esportivo/prevenção & controle , Esportes/ética , Detecção do Abuso de Substâncias/métodos , Atletas , Dopagem Esportivo/economia , Dopagem Esportivo/história , História do Século XX , História do Século XXI , Humanos , Substâncias para Melhoria do Desempenho/análise
6.
PLoS One ; 8(5): e63306, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23691018

RESUMO

This paper extends classical work on economics of doping into a multi-player game setting. Apart from being among the first papers formally formulating and analysing a multi-player doping situation, we find interesting results related to different types of Nash-equilibria (NE). Based mainly on analytic results, we claim at least two different NE structures linked to the choice of prize functions. Linear prize functions provide NEs characterised by either everyone or nobody taking drugs, while non-linear prize functions lead to qualitatively different NEs with significantly more complex predictive characteristics.


Assuntos
Dopagem Esportivo/economia , Dopagem Esportivo/psicologia , Modelos Psicológicos , Simulação por Computador , Dopagem Esportivo/métodos , Teoria dos Jogos , Jogos Experimentais , Humanos
7.
Br J Sports Med ; 46(13): 943-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22893512

RESUMO

BACKGROUND: The World Anti-Doping Agency (WADA) prescribes that drug testing is conducted in sports competitions to detect drug use in athletes. This testing includes performance-enhancing drugs as well as illicit substances such as marijuana, amphetamines and cocaine. Illicit drugs are tested for on match days but not on non-match days. Some athletes are known to use illicit substances for recreational purposes, away from competition times and this poses a serious health and welfare issue not addressed by the usual sport drug testing regimes. This paper reports the results of the first 7 years of an illicit drug-testing programme that included non-match day testing in the elite Australian Football competition, the Australian Football League (AFL). METHODS: Players in the AFL were tested for illicit drugs both in-competition and out-of-competition. Players were selected for illicit substance tests either randomly or targeted based on previous test history or time since previous test. The number of tests conducted was increased each year from 2005 to 2011 and testing was focused on high-risk times during non-competition periods. RESULTS: There were no positive match day tests. There was a significant reduction in positive tests (19-6) for illicit drugs during non-competition periods over the 7 years (p<0.0001). The reduction in positive tests may be related to player education, the greater number of tests conducted and the harm minimisation approach of the illicit drug policy. CONCLUSIONS: An illicit drugs programme using a harm minimisation strategy can work effectively alongside a sport's WADA compliant Anti-Doping Code.


Assuntos
Dopagem Esportivo/prevenção & controle , Futebol Americano , Drogas Ilícitas , Substâncias para Melhoria do Desempenho , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Adulto , Austrália , Dopagem Esportivo/economia , Humanos , Masculino
9.
J Sci Med Sport ; 14(2): 106-10, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20708965

RESUMO

Anti-doping activities in sport have shifted from secondary prevention (intervening after athletes have used) to educational strategies focused on primary prevention through promoting abstinence. There is no empirical evidence to guide targeting of anti-doping education initiatives. In this paper, a heuristic to guide education initiatives was derived by re-analysing a series of interviews (n=20) with athletes, coaches, sports managers, physiotherapists and sports nutritionists. The findings indicate primary prevention of doping may be enhanced by timing it around periods of career instability where athlete vulnerability to doping may increase as a function of winning or losing sponsorship. Sponsorship is broadly defined as financial (e.g. salary stipend) and non-financial support (e.g. training facilities). This provides a basis for targeting education interventions to promote abstinence. Two options are offered to mitigate the need to time prevention activity around career instability by lessening the effect of sponsorship on athlete doping. The first is liberalising access to legitimate performance enhancing technologies (e.g. training techniques or nutritional supplements). The second is to delay access to financial sponsorship (beyond living expenses) until retirement, with monetary gains (e.g. prize money) deposited into an account where penalties are debited if the athlete is caught doping.


Assuntos
Atletas/psicologia , Dopagem Esportivo/prevenção & controle , Intervenção Educacional Precoce , Desempenho Atlético/economia , Desempenho Atlético/psicologia , Suplementos Nutricionais/economia , Dopagem Esportivo/economia , Dopagem Esportivo/psicologia , Feminino , Apoio Financeiro , Humanos , Entrevistas como Assunto , Masculino
10.
Bioanalysis ; 1(7): 1209-24, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21083047

RESUMO

BACKGROUND: While a number of different derivatization procedures for screening GC-MS analysis of prohibited substances are followed by doping control laboratories, a unified derivatization procedure for the GC-MS analysis of 190 different doping agents was developed. RESULTS: Following preliminary experiments, a two-step derivatization procedure was selected. The evaluation of various silylation parameters, such as reagent composition, reaction time, reaction temperature, catalysts and microwave oven reaction time, for this procedure was carried out. CONCLUSION: The suitability of the developed procedure was demonstrated through application on urine samples at concentration levels of the minimum required performance limit for all tested substances. This new derivatization procedure, which significantly decreases time and cost, is suitable for a routine basis application.


Assuntos
Dopagem Esportivo/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Silanos/química , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Dopagem Esportivo/economia , Humanos , Detecção do Abuso de Substâncias/economia , Fatores de Tempo , Urinálise/economia
13.
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