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1.
Drug Test Anal ; 13(2): 460-465, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33119942

RESUMO

The current study examined the stability of several antidoping prohibited substances analytes in urine after 15-min exposure to UV-C light in a Biosafety Level 2 cabinet. The urine matrices were exposed within the original antidoping bottles with the aim to destroy DNA/RNA and possible SARS CoV-2. The analytes small molecules Phase I and Phase II metabolites and peptides, in total 444, endogenous, internal standards, and prohibited substances, pH, and specific gravity in urine were studied. The accredited analytical methods were used by Anti-Doping Laboratory Qatar for the comparison of data of the same urine samples analyzed with and without UV-C exposure. In the study conditions, no problems of stability were detected in the substances spiked in the urine samples exposed in the UV-C irradiation.


Assuntos
Anabolizantes/urina , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Contenção de Riscos Biológicos/métodos , Dopagem Esportivo , Humanos , Raios Ultravioleta
2.
Drug Test Anal ; 13(3): 529-538, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33119945

RESUMO

Antidoping testing for recombinant human erythropoietin (EPO) is routinely performed by gel electrophoresis followed by western blot analysis with primary and secondary antibodies. The two antibody steps add more than 24 h to the testing time of a purified sample. The aim of this study was to test the concept of using directly horseradish-peroxidase (HRP)-conjugated anti-EPO primary antibody, without the need for a secondary antibody, to reduce the analysis time and eliminate non-specific cross-reactivity with secondary antibodies. An in-house, periodate coupling (R&D systems, clone AE7A5) and three commercially available anti-human EPO-HRP conjugates from Genetex, Novus Biologicals and Santa Cruz were evaluated for specificity and sensitivity, using recombinant human EPO standards, negative human urine samples and urine samples from an EPO excretion study. The in-house anti-EPO-HRP conjugate was performed as well as the current two-step application of unconjugated primary and secondary antibodies used in routine analysis, with comparable specificity and sensitivity. The analysis time was markedly reduced for purified samples from 25 h with the routine method down to 7 h with the in-house HRP conjugate. Of the three commercially available conjugates tested, only the Santa Cruz anti-EPO-HRP conjugate showed comparable specificity but had lower sensitivity to both the in-house and the antibody combination currently applied routinely. The other two commercially available conjugates (Genetex and Novus Biologicals) did not show any visible bands with the EPO standards. The results clearly demonstrate the potential utility of a directly HRP-conjugated anti-EPO antibody to reduce analysis time for EPO in doping control.


Assuntos
Anticorpos/imunologia , Eritropoetina/análise , Peroxidase do Rábano Silvestre/imunologia , Detecção do Abuso de Substâncias/métodos , Western Blotting , Dopagem Esportivo/prevenção & controle , Eletroforese em Gel de Poliacrilamida , Eritropoetina/imunologia , Peroxidase do Rábano Silvestre/química , Humanos , Proteínas Recombinantes , Sensibilidade e Especificidade , Fatores de Tempo
3.
J Sports Sci ; 38(16): 1924-1932, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32543279

RESUMO

Athlete Biological Passport (ABP) is an indirect approach, implemented by WADA, aimed at detecting blood manipulation based on abnormal changes in haematological markers. Cases report the use of hyperhydration as masking method during anti-doping urine sample collection which could potentially mask suspicious fluctuations on ABP profiles. This study investigated the hyperhydration effect on haemoglobin concentration, reticulocyte percentage and OFF-hr score (an algorithm based on haemoglobin concentration and reticulocyte percentage), with and without recombinant human erythropoietin (rHuEPO) administration. A five-week clinical study performed; Baseline and rHuEPO Phase. Water and a sports drink were used as hyperhydration agents. To examine the hyperhydration effect on the normal ABP profile per volunteer, hyperhydration was implemented at 0, 24 and 48 hours during the baseline. During the rHuEPO phase, volunteers received Epoetin beta (3000 IU) with hyperhydration to be implemented at 0, 24 and 48 hours after drug administration. Blood and urine samples were collected and analysed according to WADA guidelines. No significant effect on ABP markers was observed due to hyperhydration at any time during the study. Pre- and post-hyperhydration data were not statistically different compared to individual baseline data. In conclusion, hyperhydration does not affect the ABP haematological markers under the examined conditions.


Assuntos
Biomarcadores/sangue , Dopagem Esportivo , Comportamento de Ingestão de Líquido , Hemoglobinas/análise , Contagem de Reticulócitos , Adulto , Biomarcadores/urina , Bebidas Energéticas , Eritropoetina/administração & dosagem , Humanos , Masculino , Proteínas Recombinantes/administração & dosagem , Detecção do Abuso de Substâncias/métodos , Fatores de Tempo , Água
4.
J Pharm Sci ; 108(6): 2162-2172, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30684541

RESUMO

Excessive fluid intake, that is, hyperhydration, may be adopted by athletes as a masking method during antidoping sample collection to influence the excretion patterns of doping agents and, therefore, manipulate their detection. The aim of this exploratory study was to assess the hyperhydration effect on the detection sensitivity of recombinant human erythropoietin (rHuEPO) by sodium N-lauroyl sarcosinate ("sarkosyl") polyacrylamide gel electrophoresis analysis. The influence of hyperhydration on the serum and urinary pharmacokinetic (PK) profiles of rHuEPO was also investigated. Seven healthy physically active nonsmoking Caucasian males participated in a 31-day clinical study comprising a baseline (days 0, 1-3, and 8-10) and a drug phase (days 15-17, 22-24, and 29-31). Epoetin beta was administered subcutaneously at a single dose of 3000 IU on days 15, 22, and 29. Hyperhydration was applied in the morning on 3 consecutive days (days 1-3, 8-10, 22-24, and 29-31), that is, 0, 24, and 48 h after first fluid ingestion. Water and a commercial sports drink were used as hyperhydration agents (20 mL/kg body weight). Serum and urinary concentration-time profiles were best described by a one-compartment PK model with zero-order absorption. Delayed absorption was observed after hyperhydration and, therefore, lag time was introduced in the PK model. Results showed no significant difference (p > 0.05) on serum or urinary erythropoietin concentrations under hyperhydration conditions. A trend for decreasing volume of distribution and increasing clearance after hyperhydration was observed, mainly after sports drink consumption. However, no significant differences (p > 0.05) due to hyperhydration for any of the serum PK parameters calculated by noncompartmental PK analysis were observed. Renal excretion of endogenous erythropoietin and rHuEPO, as reflected on the urinary cumulative amount, was increased approximately twice after hyperhydration and this supports the nonsignificant difference on the urinary concentrations. Analysis of serum and urine samples was able to detect rHuEPO up to 72 h after drug administration. The detection window of rHuEPO remained unaffected after water or sports drink ingestion. Hyperhydration had no effect on the detection sensitivity of EPO either in serum or urine samples.


Assuntos
Dopagem Esportivo/prevenção & controle , Eletroforese em Gel de Poliacrilamida/métodos , Eritropoetina/análise , Hematínicos/análise , Estado de Hidratação do Organismo/fisiologia , Resinas Acrílicas/química , Adulto , Eritropoetina/administração & dosagem , Eritropoetina/farmacocinética , Estudos de Viabilidade , Hematínicos/administração & dosagem , Hematínicos/farmacocinética , Humanos , Injeções Subcutâneas , Masculino , Modelos Biológicos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/análise , Proteínas Recombinantes/farmacocinética , Eliminação Renal/fisiologia , Reprodutibilidade dos Testes , Sarcosina/análogos & derivados , Sarcosina/química , Sensibilidade e Especificidade
5.
Int J Sport Nutr Exerc Metab ; 29(4): 388­396, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30507256

RESUMO

Low urinary luteinizing hormone (LH) values have been discussed as a marker to detect steroid abuse. However, suppressed LH concentrations related to highly diluted urine samples could be a misleading indication of anabolic steroid abuse. One aim of the present study was to examine the effect of hyperhydration on the interpretation of LH findings during doping control analysis and to investigate different possibilities to correct volume-related changes in urinary LH concentrations. Seven healthy, physically active, nonsmoking White males were examined for a 72-hr period, using water and a commercial sports drink as hyperhydration agents (20 ml/kg body weight). Urine samples were collected and analyzed according to the World Anti-Doping Agency's technical documents. Baseline urinary LH concentrations, expressed as the mean ± SD for each individual, were within the acceptable physiological range (7.11 ± 5.42 IU/L). A comparison of the measured LH values for both hyperhydration phases (Phase A: 4.24 ± 5.60 IU/L and Phase B: 4.74 ± 4.72 IU/L) with the baseline ("normal") values showed significant differences (Phase A: p < .001 and Phase B: p < .001), suggesting the clear effect of urine dilution due to hyperhydration. However, an adjustment of urinary LH concentrations by specific gravity based on a reference value of 1.020 seems to adequately correct the hyperhydration-induced decrease on the LH levels.


Assuntos
Dopagem Esportivo , Hormônio Luteinizante/urina , Estado de Hidratação do Organismo , Adulto , Atletas , Água Potável/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade Específica
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