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1.
Rapid Commun Mass Spectrom ; 30(7): 982-4, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26969941

RESUMO

RATIONALE: The issue of illicit performance enhancement spans human and animal sport in presumably equal measure, with prohibited substances and methods of doping conveying both ways. Due to the proven capability of unbound ionic cobalt (Co(2) (+) ) to stimulate erythropoiesis in humans, both human and equine anti-doping regulations have listed cobalt as a banned substance, and in particular in horse drug testing, thresholds for cobalt concentrations applying to plasma and urine have been suggested or established. Recent reports about the finding of substantial amounts of undeclared nickel in arguably licit performance- and recovery-supporting products raised the question whether the ionic species of this transition metal (Ni(2) (+) ), which exhibits similar prolyl hydroxylase inhibiting properties to Co(2) (+) , has been considered as a substitute for cobalt in doping regimens. METHODS: Therefore, a pilot study with 200 routine post-competition doping control horse urine samples collected from animals participating in equestrian, gallop, and trotting in Europe was conducted to provide a first dataset on equine urinary Ni(2) (+) concentrations. All specimens were analyzed by conventional inductively coupled plasma mass spectrometry (ICP-MS) to yield quantitative data for soluble nickel. RESULTS: Concentrations ranging from below the assay's limit of quantification (LOQ, 0.5 ng/mL) up to 33.4 ng/mL with a mean value (± standard deviation) of 6.1 (±5.1) ng/mL were determined for the total nickel content. CONCLUSIONS: In horses, nickel is considered a micronutrient and feed supplements containing nickel are available; hence, follow-up studies are deemed warranted to consolidate potential future threshold levels concerning urine and blood nickel concentrations in horses using larger sets of samples for both matrices and to provide in-depth insights by conducting elimination studies with soluble Ni(2) (+) -salt species. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Dopagem Esportivo , Cavalos/fisiologia , Níquel/urina , Animais , Feminino , Masculino , Espectrometria de Massas , Projetos Piloto
2.
J Vet Pharmacol Ther ; 32(2): 197-202, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19290951

RESUMO

The anti-doping rules of national and international sport federations ban any use of tetrahydrogestrinone (THG) in human as well as in horse sports. Initiated by the THG doping scandals in human sports a method for the detection of 3-keto-4,9,11-triene steroids in horse blood and urine was developed. The method comprises the isolation of the analytes by a combination of solid phase and liquid-liquid extraction after hydrolysis and solvolysis of the steroid conjugates. The concentrations of THG in blood and urine samples were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A THG excretion study on horses was conducted to verify the method capability for the analysis of postadministration urine samples. In addition, blood samples were collected to allow for determination of the pharmacokinetics of THG in horses. Following the administration of a single oral dose of 25 microg THG per kg bodyweight to 10 horses, samples were collected at appropriate intervals. The plasma levels of THG reached maximal concentrations of 1.5-4.8 ng/mL. Twenty-four hours after the administration plasma levels returned to baseline. In urine, THG was detectable for 36 h. Urinary peak concentrations of total THG ranged from 16 to 206 ng/mL. For the 10 horses tested, the mean plasma clearance of THG was 2250 mL/h/kg and the plasma elimination half-life was 1.9 h.


Assuntos
Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Gestrinone/análogos & derivados , Cavalos/metabolismo , Detecção do Abuso de Substâncias/veterinária , Espectrometria de Massas em Tandem/veterinária , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Gestrinone/sangue , Gestrinone/farmacocinética , Gestrinone/urina , Meia-Vida , Cavalos/sangue , Cavalos/urina , Masculino , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos
3.
Drug Test Anal ; 1(6): 286-91, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20355208

RESUMO

The use of prescribed antidepressants by athletes has not been restricted in human sports since 2003, after the antidepressants bupropion and amineptine were removed from the list of prohibited substances. Recent awareness of antidepressants has been stimulated by reports from the media concerning possible misuse of antidepressants among healthy athletes. The prevalence of antidepressants has been monitored over the past ten years with screening procedures routinely used by WADA-accredited laboratories. The growth in antidepressant use among athletes peaked in 2007 and 2008 after a modest increase over the first eight years of this survey. Pharmacy prescriptions for antidepressants in Germany did not show a correlated growth during this period. The increasing variety of antidepressant medications has led to a continued increase in the diversity of antidepressant substances used by athletes and the 'normal' population. The number of different sports affected by the presence of antidepressants has increased in the past decade, especially in endurance sports. The predominance of female antidepressant users in the normal population was reflected in the athletes' group. We concluded from our results that the development of antidepressant prevalence in elite sports did not correlate with that among the general public in Germany.


Assuntos
Antidepressivos/uso terapêutico , Atletas/estatística & dados numéricos , Esportes/estatística & dados numéricos , Adulto , Coleta de Dados , Dopagem Esportivo , Feminino , Alemanha , Humanos , Masculino , Prevalência , Fatores Sexuais , Adulto Jovem
4.
J Vet Pharmacol Ther ; 30(1): 86-90, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17217407

RESUMO

The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentrations were measured by liquid chromatography-tandem mass spectrometry. The plasma levels of altrenogest reached maximal concentrations of 23-75 ng/mL. Baseline values were achieved within 3 days after the final administration. Urine peak concentrations of total altrenogest ranged from 823 to 3895 ng/mL. Twelve days after the final administration concentrations were below the limit of detection (ca 2 ng/mL).


Assuntos
Cavalos/metabolismo , Congêneres da Progesterona/farmacocinética , Acetato de Trembolona/análogos & derivados , Administração Oral , Animais , Cromatografia Líquida/veterinária , Dopagem Esportivo/prevenção & controle , Masculino , Espectrometria de Massas/veterinária , Congêneres da Progesterona/administração & dosagem , Congêneres da Progesterona/sangue , Congêneres da Progesterona/urina , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/veterinária , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/sangue , Acetato de Trembolona/farmacocinética , Acetato de Trembolona/urina
5.
J Chromatogr B Biomed Sci Appl ; 723(1-2): 147-55, 1999 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-10080642

RESUMO

A method for the detection of clenbuterol in human scalp hair by gas chromatography-high-resolution mass spectrometry (GC-HRMS) is described. The sample preparation involved chemical digestion of the protein structure, which was achieved by incubating the hair with 1 M KOH at 70 degrees C. A single extraction step with tert.-butyl methyl ether provided approximately 90% of the analyte, which was dried and derivatized with N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA) to yield clenbuterol N,O-bis-trimethylsilyl (TMS). Hair was collected from four pregnant women who were therapeutically treated with Spiropent (clenbuterol-HCl) and from the infant of one female patient. Hair samples were taken during the application time and two to six months after completion of clenbuterol administration. The detection limit of the method was approximately 4 ng clenbuterol/g hair when 25 mg hair material were processed and 2 ng/g for 50 mg hair samples (corresponds to 4 pg per injection). The method allows clenbuterol to be measured retrospectively for up to at least six months. The levels of clenbuterol determined in hair ranged from 2 to 236 ng/g. No clenbuterol was found in the hair of the infant, which was taken five and a half months after delivery. To improve sample preparation, an additional purification step via immuno affinity chromatography (IAC) was integrated. The IAC purified extracts showed reduced biological background interference and an improved limit of detection (0.8 ng/g).


Assuntos
Agonistas Adrenérgicos beta/análise , Clembuterol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cabelo/química , Cromatografia de Afinidade/métodos , Feminino , Humanos , Lactente , Gravidez , Receptores Adrenérgicos beta 2/efeitos dos fármacos , Sensibilidade e Especificidade
6.
Cytotechnology ; 24(1): 19-30, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-22358593

RESUMO

The monoclonal-antibody production of an immobilized hybridoma cell line cultivated in a fluidized-bed reactor was monitored on-line for nearly 900 h. The monoclonal antibody concentration was determined by an immuno affinity-chromatography method (ABICAP). Antibodies directed against the product, e.g. IgG, were immobilized on a micro-porous gel and packed in small columns. After all IgG present in the sample was bound to the immobilized antibodies, unbound proteins were removed by rinsing the column. Elution of the bound antibodies followed and the antibodies were determined by fluorescence. The analytical procedure was automated with a robotic device to enable on-line measurements. The correlation between the on-line determined data and antibody concentrations measured by HPLC was linear.A sampling system was constructed, which was based on a pneumatically actuated in-line membrane valve integrated into the circulation loop of the reactor. Separation of the cells from the sample stream was achieved by a depth filter made of glass-fibre, situated outside the reactor. Rapid obstruction of the filter by cells or cell debris and contamination of the sample system was avoided by intermittent rinsing of the sample system with a chemical solution. The intermittent rinsing of the filter, which had a surface of 4.8 cm(2), resulted in an operational capacity of up to 40 samples (1.0 l total sample volume). Both the sampling system and the analytical device functioned without failure during this long-term culture.The culture temperature was varied between 34 and 40 °C. Raising the temperature from 34 up to 37 °C resulted in a simultaneous increase of growth and specific antibody production rate. Specific metabolic rates of glucose, lactate, glutamine and ammonium stayed constant in this temperature range. A further enhancement of temperature up to 40 °C had a negative effect on the growth rate, whereas the specific monoclonal antibody production rate showed a small increase. The other specific metabolic rates also increased in the temperature range between 38 to 40 °C.

7.
J Chromatogr B Biomed Appl ; 687(1): 93-108, 1996 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-9001957

RESUMO

The misuse of anabolic androgenic steroids (AAS) in human sports is controlled by gas chromatography-mass spectrometric analysis of urine specimens obtained from athletes. The analysis is improved with modern high-resolution mass spectrometry (HRMS). The detection and identification of metabolites of stanozolol (I) [3'-hydroxystanozolol (II) and 4 beta-hydroxystanozolol (III)] and metandienone (IV) I17 beta-methyl-5 beta-androst-1-ene-3 alpha,17 alpha-diol (V) and 18-nor-17,17-dimethyl-5 beta-androsta-1,13-dien-3 alpha-ol (VI)] with GC-HRMS at 3000 resolution yielded a large increase in the number of positive specimens. A total of 116 anabolic steroid positives were found in this laboratory in 1995 via GC-MS and GC-HRMS screening of 6700 human urine specimens collected at national and international sporting events and at out-of-competition testing. Of the 116 positive cases, 41 were detected using conventional (quadrupole) GC-MS screening. The other 75 positives were identified via GC-HRMS screening. To confirm the HRMS screening result, the urine sample was reanalyzed using a specific sample workup procedure to selectively isolate the metabolites of the identified substance. II and III were selectively isolated via immunoaffinity chromatography (IAC) using an antibody which was prepared for methyltestosterone and shows high cross reactivity to II and III. V and VI were isolated using high-performance liquid chromatography (HPLC) fractionation.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Estanozolol/urina , Detecção do Abuso de Substâncias , Humanos , Programas de Rastreamento , Metandrostenolona/urina , Manejo de Espécimes , Transtornos Relacionados ao Uso de Substâncias
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