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1.
Bioanalysis ; 12(11): 753-768, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32479744

RESUMO

Aim: Quantitative endogenous steroid profiling in blood appears as a complementary approach to the urinary module of the World Anti-Doping Agency's Athlete Biological Passport Steroidal Module for the detection of testosterone doping. To refine this approach further, a UHPLC-MS/MS method was developed for the simultaneous determination of 14 free and 14 conjugated steroids in serum. Results: The method was validated for quantitative purposes with satisfactory results in terms of selectivity, linearity range, trueness, precision and combined uncertainty (<20%). The validated method was then applied to serum samples from both healthy women and women diagnosed with mild hyperandrogenism. Conclusion: The UHPLC-MS/MS method showed promising capability in quantifying free and conjugated steroids in serum and determining variations of their concentration/distribution within serum samples from different populations.


Assuntos
Dopagem Esportivo , Esteroides/sangue , Detecção do Abuso de Substâncias , Atletas , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Hiperandrogenismo/sangue , Espectrometria de Massas em Tandem
2.
Steroids ; 71(5): 364-70, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16438998

RESUMO

The metabolic effect of multiple oral testosterone undecanoate (TU) doses over 4 weeks was assessed in seven voluntary men. The protocol was designed to detect accumulation of the substance by choosing the appropriate spot urines collections time and to study the urinary clearance of the substance after weeks of treatment. Urines were analysed by a new GC/C/isotope ratio mass spectrometry (IRMS) method to establish the delta(13)C-values of testosterone metabolites (androsterone and etiocholanolone) together with an endogenous reference compound (16(5alpha)-androsten-3alpha-ol). The significant differences in inter-individual metabolism following TU intake was illustrated by large variations in delta(13)C-values of both T metabolites (maximum Deltadelta(13)C-values = 5.5 per thousand), as well as by very stable longitudinal T/E profiles and carbon isotopic ratios in the first hours following administration. According to T/E ratios and delta(13)C-values, the washout period after 80 mg TU intake was less than 48 h for all subjects and no accumulation phenomenon was observed upon chronic oral administration.


Assuntos
Dopagem Esportivo , Variação Genética , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Administração Oral , Adulto , Isótopos de Carbono , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Valores de Referência , Testosterona/administração & dosagem , Testosterona/metabolismo , Testosterona/urina , Fatores de Tempo
3.
Clin J Am Soc Nephrol ; 10(3): 382-9, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25568216

RESUMO

BACKGROUND AND OBJECTIVES: Evaluation of glomerular hyperfiltration (GH) is difficult; the variable reported definitions impede comparisons between studies. A clear and universal definition of GH would help in comparing results of trials aimed at reducing GH. This study assessed how GH is measured and defined in the literature. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Three databases (Embase, MEDLINE, CINAHL) were systematically searched using the terms "hyperfiltration" or "glomerular hyperfiltration". All studies reporting a GH threshold or studying the effect of a high GFR in a continuous manner against another outcome of interest were included. RESULTS: The literature search was performed from November 2012 to February 2013 and updated in August 2014. From 2013 retrieved studies, 405 studies were included. Threshold use to define GH was reported in 55.6% of studies. Of these, 88.4% used a single threshold and 11.6% used numerous thresholds adapted to participant sex or age. In 29.8% of the studies, the choice of a GH threshold was not based on a control group or literature references. After 2004, the use of GH threshold use increased (P<0.001), but the use of a control group to precisely define that GH threshold decreased significantly (P<0.001); the threshold did not differ among pediatric, adult, or mixed-age studies. The GH threshold ranged from 90.7 to 175 ml/min per 1.73 m(2) (median, 135 ml/min per 1.73 m(2)). CONCLUSION: Thirty percent of studies did not justify the choice of threshold values. The decrease of GFR in the elderly was rarely considered in defining GH. From a methodologic point of view, an age- and sex-matched control group should be used to define a GH threshold.


Assuntos
Glomérulos Renais/fisiopatologia , Insuficiência Renal Crônica/fisiopatologia , Terminologia como Assunto , Taxa de Filtração Glomerular , Humanos , Valores de Referência
4.
Soz Praventivmed ; 47(2): 107-15, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12134728

RESUMO

OBJECTIVES: In the absence of a gold standard, the assessment of physical activity in children remains difficult. To record physical activity with a pedometer and to examine to what extent it is correlated with VO2max. METHODS: Survey on physical activity and fitness; 233 Swiss adolescents aged 11 to 15 carried a pedometer (Pedoboy) during seven consecutive days. VO2max was estimated through an endurance shuttle run test. RESULTS: The physical activity recorded by the pedometer did not vary from one day to the other (p > 0.05). The physical activity was higher among boys than among girls (p < 0.001) and higher among younger adolescents (6th versus 8th grade; p < 0.001). The correlation between physical activity and estimated VO2max was 0.30 (p < 0.01). CONCLUSIONS: The use of a pedometer to assess physical activity over one entire week is feasible among adolescents. The record provided by the pedometer gives an objective measure of the usual physical activity and, as such, is relatively well correlated with aerobic capacity.


Assuntos
Exercício Físico/fisiologia , Comportamentos Relacionados com a Saúde , Monitorização Ambulatorial/instrumentação , Oxigênio/sangue , Adolescente , Criança , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Resistência Física/fisiologia , Aptidão Física/fisiologia , Suíça
5.
Eur J Appl Physiol ; 98(4): 329-40, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16896724

RESUMO

Anabolic androgenic steroids (AAS) are doping agents that are mostly used for improvement of strength and muscle hypertrophy. In some sports, athletes reported that the intake of AAS is associated with a better recovery, a higher training load capacity and therefore an increase in physical and mental performances. The purpose of this study was to evaluate, the effect of multiple doses of AAS on different physiological parameters that could indirectly relate the physical state of athletes during a hard endurance training program. In a double blind settings, three groups (n = 9, 8 and 8) were orally administered placebo, testosterone undecanoate or 19-norandrostenedione, 12 times during 1 month. Serum biomarkers (creatine kinase, ASAT and urea), serum hormone profiles (testosterone, cortisol and LH) and urinary catecholamines (noradrenalin, adrenalin and dopamine) were evaluated during the treatment. Running performance was assessed before and after the intervention phase by means of a standardized treadmill test. None of the measured biochemical variables showed significant impact of AAS on physical stress level. Data from exercise testing on submaximal and maximal level did not reveal any performance differences between the three groups or their response to the treatment. In the present study, no effect of multiple oral doses of AAS on endurance performance or bioserum recovery markers was found.


Assuntos
Anabolizantes/farmacologia , Androgênios/farmacologia , Resistência Física/efeitos dos fármacos , Esteroides/farmacologia , Estresse Psicológico/sangue , Adulto , Androstenodiona/análogos & derivados , Androstenodiona/farmacologia , Biomarcadores , Catecolaminas/urina , Método Duplo-Cego , Teste de Esforço , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Hormônios/sangue , Humanos , Hidrocortisona/sangue , Ácido Láctico/sangue , Masculino , Aptidão Física/fisiologia , Corrida/fisiologia , Estresse Psicológico/urina , Testosterona/farmacologia
6.
Clin J Sport Med ; 15(3): 158-66, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15867559

RESUMO

OBJECTIVE: Nandrolone is an anabolic steroid widely used in several sports. The numerous nandrolone positive cases in the recent years (International Olympic Committee statistics) led to several studies in the antidoping field. Nevertheless, essential questions pertaining to nandrolone endogenous production, the effects of physical exercise on the excretion of nandrolone metabolites, and contamination from nutritional supplements must still be addressed. The purpose of this study was to evaluate the influence of exhaustive exercises on 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) urinary excretion rates after administration of labeled nandrolone. SETTING AND PARTICIPANTS: A total of 34 healthy male Caucasian volunteers from the Institute of Sports Sciences and Physical Education (University of Lausanne) applied to participate in the study. All subjects were free from any physical drug addiction and were instructed strictly to avoid any nutritional supplement or steroid before and during the study. The participants were randomly dispatched in 2 groups in a double-blind way: a placebo group and a group treated with C-labeled nandrolone. MAIN OUTCOME MEASUREMENTS: The urinary concentrations of the 2 main nandrolone metabolites, 19-NA and 19-NE, were measured using gas chromatography coupled with mass spectrometry. In addition, clinical parameters such as creatinine, total protein, and beta2-microglobuline levels were determined using immunologic assays. RESULTS: After an oral ingestion of a 25 mg 3,4-C2-nandrolone dose, followed by a second identical dose 24 hours later, 19-NA and 19-NE could be detected in the urine for a period of 6 days after the initial intake. Despite several interesting observations, the measurements were very scattered and did not appear to be significantly influenced by exercise sessions in the athlete population. CONCLUSIONS: The results of this study suggest that physical exercise cannot be considered as a reliable parameter that systematically affects nandrolone metabolite concentrations in the urine.


Assuntos
Anabolizantes/farmacocinética , Teste de Esforço , Tolerância ao Exercício/efeitos dos fármacos , Nandrolona/farmacocinética , Esportes/fisiologia , Urina/química , Administração Oral , Adulto , Anabolizantes/administração & dosagem , Análise de Variância , Método Duplo-Cego , Humanos , Masculino , Nandrolona/administração & dosagem , Probabilidade , Estudos Prospectivos , Radioisótopos , Medição de Risco , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias , Urinálise
7.
Clin Chem ; 50(2): 355-64, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14633920

RESUMO

BACKGROUND: Nandrolone is one of the most abused anabolic steroids, and its use in doping is increasing, as revealed by numerous positive cases during recent years in various sports. Different authors have reported the possible natural production of nandrolone metabolites in humans, and some of these authors argued that exhaustive exercise could increase nandrolone production in the body or induce dehydration and consequently lead to an increase of nandrolone metabolites in urine. METHODS: Volunteers (n = 22) ingested two 25-mg doses of [(13)C]nandrolone at 24-h intervals and collected urine specimens for 5 days. The labeled nandrolone metabolites 19-norandrosterone and 19-noretiocholanolone were identified and quantified by gas chromatography-mass spectrometry. RESULTS: Interindividual variability was observed in nandrolone excretion patterns and kinetics, as well as for the noretiocholanolone:norandrosterone ratio. The amounts of nandrolone metabolites measured at the excretion peak varied between 1180 and 38 661 microg/L for norandrosterone and 576 and 12 328 microg/L for noretiocholanolone. At the end of the excretion period, the noretiocholanolone:norandrosterone ratio was sometimes >1. The analysis of numerous spot-urine samples allowed the determination of an acceptable correlation between urinary creatinine and specific gravity for placebo- and steroid-treated individuals: y = 0.0052ln(x) + 1.0178 (r(2) = 0.8142) and y = 0.0068ln(x) + 1.0172 (r(2) = 0.7730), respectively. CONCLUSIONS: The excretion kinetics and patterns of labeled nandrolone show interindividual variability. More investigations are currently underway to estimate the influence of exhaustive exercises on excretion of labeled nandrolone metabolites in urine.


Assuntos
Nandrolona/metabolismo , Esportes , Detecção do Abuso de Substâncias , Adulto , Isótopos de Carbono , Dopagem Esportivo , Estranos/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Nandrolona/farmacocinética , Nandrolona/urina
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