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1.
Scand J Med Sci Sports ; 29(10): 1489-1500, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206799

RESUMO

The aim of the present study was to investigate if hyperhydration could influence the excretion and subsequent detection of budesonide (BDS) and its main metabolites (6ß-hydroxy-budesonide and 16α-hydroxy-prednisolone) during doping control analysis by leading to concentrations below the WADA reporting level (30 ng/mL). The influence of hyperhydration on the plasma and urinary pharmacokinetic (PK) profiles of BDS and metabolites was also examined. Seven healthy physically active non-smoking Caucasian males participated in a 15-day clinical study. BDS was administered orally at a single dose of 9 mg on Days 1, 7, and 13. Hyperhydration was applied in the morning on two consecutive days, that is, 0 and 24 hours after first fluid ingestion. Water and a commercial sports drink were used as hyperhydration agents (20 mL/kg body weight). Results showed no significant difference (P > 0.05, 95% CI) on plasma or urinary PK parameters under hyperhydration conditions for all the analytes. However, significant differences (P < 0.05, 95% CI) due to hyperhydration were observed on the urinary concentrations of BDS and metabolites. To compensate the dilution effect due to hyperhydration, different adjustment methods were applied based on specific gravity, urinary flow rate, and creatinine. All the applied methods were able to adjust the concentration values close to the baseline ones for each analyte; however, specific gravity was the optimum method in terms of effectiveness and practicability. Furthermore, no masking of the detection sensitivity of BDS or its metabolites was observed due to hyperhydration either in plasma or urine samples.


Assuntos
Budesonida/farmacocinética , Ingestão de Líquidos , Estado de Hidratação do Organismo , Administração Oral , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Prednisolona/análogos & derivados , Prednisolona/sangue , Prednisolona/urina
2.
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
3.
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
4.
Bioanalysis ; 8(21): 2265-2279, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27665839

RESUMO

The 2016 Olympic and Paralympic Games, the biggest event in human sports, was held in Rio de Janeiro with more than 10,500 athletes from 206 countries over the world competing for the highest of sports honors, an Olympic medal. With the hope that the Olympic ideal accompanies all aspects of the XXXI Olympiad, WADA accredited antidoping laboratories use the spearhead of analytical technology as a powerful tool in the fight against doping. This review summarizes the main analytical developments applied in antidoping testing methodology combined with the main amendments on the WADA regulations regarding analytical testing starting from the 2012 London Olympics until the 2016 Olympic Games in Rio de Janeiro.


Assuntos
Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas , Substâncias para Melhoria do Desempenho/análise , Espectrometria de Massas em Tandem , Anabolizantes/análise , Transfusão de Sangue , Cromatografia Líquida de Alta Pressão , Humanos , Agências Internacionais , Hormônios Peptídicos/análise
5.
J Pharm Biomed Anal ; 90: 207-14, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24389463

RESUMO

A simplified gas chromatographic-mass spectrometric (GC-MS) analytical method, involving a novel derivatization procedure was developed for monitoring busulfan (Bu) plasma concentrations in populations undergoing bone marrow transplantation. Plasma samples (500 µL) containing Bu-d8 as internal standard were extracted with ethyl acetate (2 mL) followed by centrifugation (1800 rpm, 5 min) and evaporation of the organic layer under nitrogen flow (50 °C). The dry residue was reconstituted with 100 µL iodine solution in acetonitrile (0.25%, w/v) and 3 µL were injected into the GC-MS system at 250 °C. Conversion of Bu to 1,4-diiodobutane was accomplished on-line without the need of an extra derivatization step. MS was operated at selected ion monitoring mode at m/z 183 and 191 corresponding to Bu and Bu-d8 derivatives. Total analysis time was 11.5 min. Calibration curves were linear (mean r=0.9996) over a concentration range of 25-3651 ng/mL using a (1/x)-weighted scheme. Limit of detection and lower limit of quantitation were 10.6 and 25 ng/mL, respectively. Overall accuracy Er (%) was ranging from -5.10% to 10.5%. Within- and between-run RSD (%) were lower 4.51% and 2.15%, respectively. Overall recovery of Bu was equal to 69.3±4.56% (RSD (%)). The present method is sensitive and specific, requiring a simple sample preparation procedure and short analysis time, advantages crucial for therapeutic drug monitoring of Bu in clinical practice and application in pharmacokinetic studies.


Assuntos
Antineoplásicos Alquilantes/farmacocinética , Bussulfano/farmacocinética , Monitoramento de Medicamentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Calibragem , Humanos , Hidrocarbonetos Iodados/análise , Limite de Detecção , Espectrometria de Massas , Reprodutibilidade dos Testes , Fatores de Tempo
6.
Blood Cells Mol Dis ; 41(2): 203-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18621559

RESUMO

Transcriptional and post-transcriptional control mechanisms have a differential impact on cellular physiology depending on activation status. Several lines of evidence suggest that chronic lymphocytic leukemia (CLL) malignant B cells resemble antigen-experienced and activated B cells. In the present study, we investigated the expression of transferrin receptor 1 (TfR1, CD71), one of the "classical" markers up-regulated upon B-cell activation, and TfR2, a novel receptor for transferrin, in peripheral blood CD19+ B cells from ten healthy individuals and 76 patients with CLL so as to gain insight into potential disease-related differences in underlying regulatory mechanisms. Marked differences in the production and expression of these receptors were detected in malignant but not in normal B cells. Specifically, TfR1 mRNA and protein levels were significantly higher in comparison to TfR2, both in normal and malignant B cells. Furthermore, discrepancies between TfR mRNA and protein expression were observed in CLL; in contrast, mRNA and protein expression levels were generally concordant in normal B cells. Exposure to actinomycin D decreased TfR1 and TfR2 mRNA levels in normal CD19+ B cells but had no effect on CLL malignant cells. The protein synthesis inhibitor cycloheximide had opposing effects in normal vs. CLL malignant B cells: thus, TfR1 and TfR2 mRNA levels were increased in normal B cells, whereas they were unaffected or even suppressed in CLL malignant B cells. These results allude to differential regulation of TfR1 and TfR2 expression in normal B cells vs. CLL. In normal B cells, transcriptional mechanisms exert a critical control over TfR1 and TfR2 expression, whereas in CLL post-transcriptional mechanisms seem to play a complementary and perhaps more important role. This type of control appears to be especially suited for modulation of genes implicated in proliferation of activated cells, like CLL malignant B cells.


Assuntos
Linfócitos B/química , Regulação Neoplásica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/patologia , Receptores da Transferrina/análise , Antígenos CD/análise , Antígenos CD/genética , Estudos de Casos e Controles , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Humanos , RNA Mensageiro/análise , Receptores da Transferrina/genética , Regulação para Cima
7.
Leuk Res ; 30(2): 183-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16054692

RESUMO

Transferrin receptor (TfR)-1 and 2 mRNA and CD71 (TfR1) expression was analyzed in 118 CLL patients. Ninety-five out of 109 analyzed cases expressed CD71, mostly at a high level; 60% of CD71 (+) cases were IGH-mutated. All samples were TfR1 mRNA (+); TfR2-alpha/beta mRNA was detected in, respectively, 52/102 and 100/109 cases. Competitive RT-PCR showed widely divergent levels of TfR1 mRNA in cases with high CD71 expression, alluding to post-transcriptional control of TfR1 expression in CLL. The almost uniformly high CD71 expression in CLL is in keeping with the activated status of neoplastic cells, regardless of IGH mutational load.


Assuntos
Antígenos CD/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Receptores da Transferrina/genética , ADP-Ribosil Ciclase 1/análise , Adulto , Idoso , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Imunofenotipagem , Lectinas Tipo C , Leucemia Linfocítica Crônica de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , RNA Mensageiro/análise , Receptores da Transferrina/análise
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