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1.
Clin Chim Acta ; 557: 117860, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508572

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common infertility disorder which affects reproductive-aged women. However, metabolic change profiles of follicular fluid (FF) in lean and obese women diagnosed with and without PCOS remains unclear. METHODS: 95 infertile women were divided into four subgroups: LC (lean control), OC (overweight control), LP (lean PCOS), and OP (overweight PCOS). The FF samples were collected during oocyte retrieval and assayed by ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) metabolomics. RESULTS: A total of 236 metabolites were identified by metabolic analysis. The pathway enrichment analysis revealed that the glycerophospholipid metabolism (impact = 0.11182), ether lipid metabolism (impact = 0.14458), and primary bile acid biosynthesis (impact = 0.03267) were related to metabolic pathway between PCOS and control. Correlation analyses showed that epitestosterone sulfate was found positively correlated with fertilization rate in PCOS, while falcarindione, lucidone C. and notoginsenoside I was found to be negatively correlated. The combined four biomarkers including lucidone C, epitestosterone sulfate, falcarindione, and notoginsenoside I was better in predicting live birth rate, with AUC of 0.779. CONCLUSION: The follicular fluid of women with PCOS showed unique metabolic characteristics. Our study provides better identification of PCOS follicular fluid metabolic dynamics, which may serve as potential biomarkers of live birth.


Assuntos
Ciclopentanos , Infertilidade Feminina , Síndrome do Ovário Policístico , Gravidez , Feminino , Humanos , Adulto , Líquido Folicular/metabolismo , Nascido Vivo , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/metabolismo , Infertilidade Feminina/diagnóstico , 60705 , Sobrepeso , Epitestosterona/análise , Epitestosterona/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Fertilização In Vitro , Biomarcadores/análise , Sulfatos/análise , Sulfatos/metabolismo
2.
Drug Test Anal ; 13(10): 1735-1742, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34228890

RESUMO

At the Swedish national forensic toxicology laboratory, a measured testosterone/epitestosterone (T/E) ratio ≥ 12 together with testosterone/luteinizing hormone (T/LH) in urine > 400 nmol/IU is considered as a proof of exogenous testosterone administration. However, according to the rules of the World Anti-Doping Agency (WADA), samples with T/E ratio > 4 are considered suspicious and shall be further analysed by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) to confirm the origin of testosterone and its metabolites. The aim of this study was to investigate the possibility of false negative results and to estimate the frequency of negative results using the current criteria for detection of abuse of testosterone in forensic investigations. Urine and serum samples were collected by the police at suspected infringement of the doping law in Sweden. Fifty-eight male subjects were included in the study. Urinary testosterone was determined by gas chromatography-mass spectrometry (GC-MS), serum testosterone and LH-by immunoassay. The origin of testosterone and its metabolites was confirmed by means of GC-C-IRMS. Twenty-six of the 57 analysed subjects tested positive for exogenous testosterone using the criteria T/E ≥ 12 combined with T/LH > 400 nmol/IU. The IRMS analyses confirmed 47 positives; thus, 21 were considered false negatives. Negative predictive value was 32% (95% confidence interval [CI]: 16%-50%) and sensitivity 55%. No false positive subjects were found. The number of false negative cases using the current criteria for the detection of testosterone abuse and hence the low sensitivity indicates a need to discuss introduction of new strategies in forensic doping investigations.


Assuntos
Doping nos Esportes/prevenção & controle , Epitestosterona/urina , Hormônio Luteinizante/urina , Testosterona/urina , Adulto , Epitestosterona/análise , Reações Falso-Negativas , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hormônio Luteinizante/análise , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias/métodos , Suécia , Testosterona/análise , Adulto Jovem
3.
Drug Test Anal ; 13(8): 1576-1579, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33864421

RESUMO

To detect doping with pseudo-endogenous anabolic steroids in sports, a urinary steroid profile with glucuronidated plus unconjugated androgens is used. In addition to analyze androgen glucuronide metabolites, it can be of interest to also include sulfate metabolites in the urinary steroid profile. The combined ratios of epitestosterone sulfate/epitestosterone glucuronide to the ratios of testosterone sulfate/testosterone glucuronide ((ES/EG)/(TS/TG)) have previously been investigated as a complementary biomarker for testosterone doping. In this restudy, the aim was to evaluate this biomarker in a larger study sample population. A single dose of 500-mg testosterone enanthate was administered to 54 healthy male volunteers. Urine was collected prior to (Day 0) administration and throughout 15 days and analyzed for the sulfate and glucuronide conjugates of testosterone and epitestosterone. The results show that the combined ratio increased to a larger extent than the traditional T/E ratio in all subjects. This increase was independent on UGT2B17 gene polymorphism. Moreover, a delayed peak of the combined ratio was observed in ~60% of the participants. The results confirm that complementary analyses of the sulfate metabolites may be a useful approach to detect testosterone doping in men.


Assuntos
Epitestosterona/análise , Testosterona/análogos & derivados , Testosterona/urina , Adolescente , Adulto , Biomarcadores , Doping nos Esportes , Glucuronosiltransferase/genética , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor/genética , Polimorfismo Genético , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/métodos , Testosterona/análise , Congêneres da Testosterona , Adulto Jovem
4.
Drug Test Anal ; 12(8): 1019-1030, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32307878

RESUMO

Testosterone treatment stimulates the production of red blood cells and alters iron homeostasis. Thus, we investigated whether the 'haematological module' of the athlete biological passport (ABP) used by the World Anti-Doping Agency can be used to indicate misuse of testosterone. Nineteen eugonadal men received intramuscular injections of either 250 mg Sustanon®, a blend of four testosterone esters, or placebo on days 0 and 21 in a randomized, placebo-controlleddouble-blind design. Urine samples and blood samples were collected twice pre-treatment, at least 5 days apart, and on days 1, 3, 5, 10 and 14 post-injections to assess steroidal and haematological biomarkers of the ABP. The steroidal profile was flagged suspicious in all Sustanon®-treated subjects, whereas the haematological profile was flagged suspicious in six out of nine subjects. When both sensitivity and specificity were considered, reticulocyte percentage (RET%) appeared as the best marker of the haematological module for implying testosterone ester misuse. Atypical blood passport samples were used to select time points for further isotope-ratio mass spectrometry (IRMS) analysis of testosterone and its metabolites in simultaneously collected urine. In addition to the testosterone (T) to epitestosterone (E) ratio, the RET% and OFF-Score could help identify suspicious samples for more targeted IRMS testing. The results demonstrate that unexpected fluctuations in RET% can indicate testosterone doping if samples are collected 3-10 days after injection. From an anti-doping perspective, the haematological and steroidal modules of the ABP should complement each other when planning targeted follow-up testing and substantiating likely misuse of testosterone.


Assuntos
Doping nos Esportes/prevenção & controle , Espectrometria de Massas/métodos , Reticulócitos/citologia , Testosterona/administração & dosagem , Adulto , Atletas , Biomarcadores/análise , Método Duplo-Cego , Epitestosterona/análise , Humanos , Injeções Intramusculares , Masculino , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias/métodos , Testosterona/análise , Testosterona/farmacologia , Fatores de Tempo , Adulto Jovem
5.
J Steroid Biochem Mol Biol ; 185: 47-56, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031148

RESUMO

Growth and development of an embryo or fetus during human pregnancy mainly depend on intact hormone biosynthesis and metabolism in maternal amniotic fluid (AF). We investigated the hormonal milieu in AF and developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of 14 sulfated and 6 unconjugated steroids in AF. 65 A F samples (male: female = 35: 30) of mid-gestation ranging from 16th week of gestation to 25th week of gestation were analyzed. Reference data of 20 steroid levels in AF of healthy women were provided. 13 sulfated and 3 unconjugated steroids were for the first time quantified in AF by LC-MS/MS. Highest concentrations were found for pregnenolone sulfate (PregS: mean ±â€¯SD, 8.6 ±â€¯3.7 ng/mL), 17α-hydroxypregnenolone sulfate (17OHPregS: 4.9 ±â€¯2.0 ng/mL), epitestosterone sulfate (eTS: 7.3 ±â€¯3.6 ng/mL), 16α-hydroxydehydroepiandrosterone sulfate (16OH-DHEAS: 21.5 ±â€¯10.7 ng/mL), androsterone sulfate (AnS: 9.2 ±â€¯7.4 ng/mL), estrone sulfate (E1S: 3.0 ±â€¯3.0 ng/mL), estriol 3-sulfate (E3S: 8.1 ±â€¯4.0 ng/mL) and estriol (E3: 1.2 ±â€¯0.4 ng/mL). Only testosterone (T) showed a significant sex difference (p < 0.0001). Correlations between AF steroids mirrored the steroid metabolism of the feto-placental unit, and not only confirmed the classical steroid pathway, but also pointed to a sulfated steroid pathway.


Assuntos
Líquido Amniótico/química , Segundo Trimestre da Gravidez/fisiologia , Esteroides/análise , 17-alfa-Hidroxipregnenolona/análise , Androsterona/análise , Cromatografia Líquida , Desidroepiandrosterona/análise , Epitestosterona/análise , Estriol/análogos & derivados , Estriol/análise , Estrona/análogos & derivados , Estrona/análise , Feminino , Idade Gestacional , Humanos , Masculino , Gravidez , Pregnenolona/análise , Espectrometria de Massas em Tandem
6.
Drug Test Anal ; 10(11-12): 1744-1754, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30315670

RESUMO

The impact of dehydroepiandrosterone (DHEA) administration has been widely studied for anti-doping purposes in men, whereas only a few studies have been performed in women. In the present study, the impact of DHEA on the steroid profile parameters and their carbon isotopic ratios was explored. Eleven healthy young women and 10 healthy young men received two treatments: One with 100 mg/day of DHEA for 28 days and one with a placebo according to a double-blind crossover protocol. Urine and saliva (only in females) samples were collected before and for 72 hours after each short-term treatment. In all female subjects, concentrations of the urinary parameters of the steroid profile were highly impacted by short-term DHEA administration including epitestosterone (E). Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) analysis was performed and positive results were observed for E in the four female subjects where E concentration was adequate for such analysis, whereas men results remained negative for E. Last, the ability of the Anti-Doping Administration and Management System (ADAMS) software used for the athlete biological passport to identify such doping was assessed. Of the 11 passports generated for female subjects, 10 were automatically classified as an atypical passport finding (ATPF). For the remaining passport with normal status in one woman, the variability of the concentrations prevented the ADAMS software from adjusting individual limits. The most impacted markers in women were T/E and 5αAdiol/E, with a detection window of 36 hours for 5αAdiol/E. In addition, good correlations were observed for DHEA and T concentrations in urine and saliva in females.


Assuntos
Desidroepiandrosterona/administração & dosagem , Cromatografia Gasosa-Espectrometria de Massas/métodos , Saliva/química , Esteroides/análise , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Adulto , Biomarcadores/análise , Biomarcadores/urina , Isótopos de Carbono/análise , Isótopos de Carbono/urina , Desidroepiandrosterona/análise , Desidroepiandrosterona/urina , Doping nos Esportes , Método Duplo-Cego , Epitestosterona/análise , Epitestosterona/urina , Feminino , Humanos , Masculino , Testosterona/análise , Testosterona/urina , Adulto Jovem
7.
Drug Test Anal ; 9(9): 1328-1336, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27717154

RESUMO

Detection of testosterone and/or its pro-drugs in the gelding is currently regulated by the application of an international threshold for urinary testosterone of 20 ng/mL. The use of steroid ratios may provide a useful supplementary approach to aid in differentiating between the administration of these steroids and unusual physiological conditions that may result in atypically high testosterone concentrations. In the current study, an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantify testosterone (T) and epitestosterone (E). The method was used to analyze 200 post-race urine samples from geldings in order to generate the ratios for the reference population. Following statistical analysis of the data, an upper limit of 5 for T:E ratio in geldings is proposed. Samples collected from 15 geldings with atypical urinary testosterone concentrations (>15 ng/mL) but otherwise normal steroid profile, had T:E ratios within those observed for the reference population. The applicability of an upper T:E ratio to detect an administration was demonstrated by the analysis of a selection of incurred samples from testosterone propionate, dehydroepiandrosterone (DHEA), and a mixture of DHEA and pregnenolone (Equi-Bolic®) administrations. These produced testosterone concentrations above the threshold of 20 ng/mL, but also T:E ratios above the proposed limit of 5. In conclusion, consideration of the T:E ratio appears to be a valuable complementary aid to evaluate whether an atypical testosterone concentration could be caused by a natural biological outlier as opposed to the administration of these steroids. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Líquidos Corporais/química , Desidroepiandrosterona/análise , Doping nos Esportes/estatística & dados numéricos , Epitestosterona/análise , Esteroides/análise , Espectrometria de Massas em Tandem/métodos , Testosterona/análise , Animais , Cromatografia Líquida , Desidroepiandrosterona/urina , Epitestosterona/urina , Cavalos , Humanos , Pró-Fármacos , Esteroides/urina , Detecção do Abuso de Substâncias , Testosterona/urina
8.
J Steroid Biochem Mol Biol ; 165(Pt B): 212-218, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27328448

RESUMO

Testosterone (T) has traditionally been the most commonly reported doping agent by doping control laboratories. The screening of T misuse is performed by the quantification of six endogenous androgenic steroids and the ratio T/E included in the Athlete Biological Passport (ABP). The inclusion of additional metabolites can improve the screening capabilities of ABP. In this study, the potential of 3α-glucuronide-6ß-hydroxyandrosterone (6OH-Andros3G) and 3α-glucuronide-6ß-hydroxyetiocholanolone (6OH-Etio3G) as markers of T oral administration was evaluated. These glucuronides have been shown to be resistant to enzymatic hydrolysis and their quantification by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was reported as the only way to obtain feasible results. Urine samples were collected from five volunteers before and after the oral administration of 40mg of T undecanoate and were analyzed by a LC-MS/MS method recently developed. Concentration of 6OH-Andros3G and 6OH-Etio3G compounds and those of the glucuronides of T (TG), epitestosterone (EG), androsterone and etiocholanolone were established and different concentration ratios were calculated. The detection windows (DWs) for the T administration obtained by each selected ratio were compared to the one of TG/EG. The results showed that four out of the nine tested markers presented DWs much larger for all volunteers than those obtained by the World Anti-Doping Agency established T/E marker or other alternative markers. The 6OH-Andros3G/EG, 6OH-Etio3G/EG, 6OH-Andros3G/TG and 6OH-Etio3G/TG markers were able to identify the T abuse up to 96h after the administration, extending our detection capability for the misuse up to 84h more than the classic marker. The importance of these markers was also highlighted by their prolonged capacity to detect the T misuse in the case of one volunteer whose TG/EG barely exceeded his individual threshold. As a consequence, the four markers presented in this study seem to have an exceptional potential as biomarkers of T oral administration.


Assuntos
Glucuronídeos/análise , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Administração Oral , Androsterona/análise , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão , Doping nos Esportes/prevenção & controle , Epitestosterona/análise , Etiocolanolona/análise , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Hidrólise , Masculino , Reprodutibilidade dos Testes , Esteroides/análise , Espectrometria de Massas em Tandem , Testosterona/administração & dosagem , Testosterona/análise
9.
Drug Test Anal ; 8(11-12): 1197-1203, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27714988

RESUMO

The laboratory profile of intranasal testosterone gel has not been previously reported from an anti-doping perspective. Because intranasal testosterone gel is newly available as a commercial product, we sought to examine the laboratory parameters following administration of this formulation, with particular attention to anti-doping guidelines. Five healthy and active male subjects were administered testosterone intranasal gel three times daily for four weeks, using a pattern of five consecutive days on, two days off. Urine was collected after each five-day round of drug administration and analyzed using a full steroid screen and isotope ratio mass spectrometry (IRMS). Windows of detection for elevated testosterone/epitestosterone (T/E) and other steroid ratios, World Anti-Doping Agency (WADA) athlete biological passport (ABP) findings, and IRMS results were analyzed in this study. In the 0-24 h window post-administration, 70% of samples were flagged with a suspicious steroid profile and 85% were flagged as atypical passport findings according to the WADA ABP steroid module. In the 24-48 h window, 0% of samples displayed suspicious steroid profiles while 40% resulted in atypical passport findings. IRMS testing confirmed the presence of exogenous testosterone in 90% and 40% of samples in the 0-24 h and 24-48 h windows post-administration, respectively. Additionally, IRMS data were analyzed to determine commonalities in the population changes in δ13 C values of testosterone, androsterone, etiocholanolone, 5αAdiol, and 5ßAdiol. Though no discernible metabolic trend of the route of administration was identified, we discovered that intranasal gel testosterone is detectable using conventional anti-doping tests. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Administração Intranasal/métodos , Androsterona/análise , Biomarcadores/análise , Isótopos de Carbono/química , Epitestosterona/análise , Etiocolanolona/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/análise , Detecção do Abuso de Substâncias/métodos , Testosterona/administração & dosagem , Androsterona/química , Atletas , Biomarcadores/metabolismo , Doping nos Esportes , Epitestosterona/química , Etiocolanolona/química , Humanos , Espectrometria de Massas , Esteroides/química , Testosterona/química , Fatores de Tempo
10.
J Pharm Biomed Anal ; 67-68: 154-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22559991

RESUMO

The feasibility of using hair analysis as a complimentary test in doping control has received increased attention in the scientific community. The aim of the study was to take a step forward to this goal and develop a method that, for the first time, is able to detect testosterone (T) and epitestosterone (E) in human hair, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and alkali digestion followed by extraction using pentane. The method was linear within the quantification range of 0.25-100 pg/mg for T and 0.5-100 pg/mg for E, with determination coefficient (r²) values >0.9987. The limits of detection for T and E were 0.1 pg/mg and 0.25 pg/mg respectively. The accuracy, precision and extraction recovery of the assay were satisfactory for the detection of T and E when ca. 50 mg hair was processed. The validated method was successfully applied for the analysis of 75 hair samples collected from healthy volunteers (65.3% males), with the concentration of T between 0.7-11.81 pg/mg and 0.33-6.05 pg/mg and the concentration of E between 0.63-8.27 pg/mg and 0.52-3.88 pg/mg in males and in females respectively. In males, the T levels were significantly higher (p=0.020) but there was no difference in the E levels (p=0.359). However, E was not detectable in 34 samples (of which 19 were females). The T and E levels showed linear correlation (r=0.698, p<0.001) with average T/E ratio of 1.32±0.7. The newly developed analytical method was rapid, facile, sensitive, selective, reproducible and reliable for determining the levels of T and E in hair and thus for calculating the T/E ratio in hair.


Assuntos
Cromatografia Líquida/métodos , Epitestosterona/análise , Cabelo/química , Espectrometria de Massas em Tandem/métodos , Testosterona/análise , Feminino , Humanos , Masculino , Padrões de Referência
11.
Physiol Res ; 61(2): 221-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22292719

RESUMO

In order to assess whether intratesticular hormone content may be helpful for prediction of successful conception in men with fertility problems, five sex steroids, testosterone, dihydrotestosterone, androstenedione, estradiol and, for the first time epitestosterone, were measured in testicular tissue obtained by surgical retrieval from total 84 men. The group consisted of non-obstructive azoospermic men, aged 21-67 years who attended the centre for in vitro fertilization. Steroids after ether extraction and solvent partition were separated by high performance liquid chromatography and then measured by specific radioimmunoassays. The values varied considerably with means ± S.D. 2.43±2.47, 0.27±0.24, 0.080±0.13, 0.071±0.089 and 0.31±0.27 for testosterone, dihydrotestosterone, androstenedione, estradiol and epitestosterone, respectively.


Assuntos
Hormônios Esteroides Gonadais/análise , Testículo/química , Adulto , Idoso , Androstenodiona/análise , Azoospermia/metabolismo , Di-Hidrotestosterona/análise , Epitestosterona/análise , Estradiol/análise , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Testículo/metabolismo , Testosterona/análise
12.
Drug Test Anal ; 3(11-12): 814-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22102298

RESUMO

In the present study, the content of a number of black market testosterone products collected in Austria has been analyzed. Additionally, (13) C/(12) C ratios were measured for testosterone in the products after cleavage of the testosterone ester. The aim was to determine whether some of these products had similar (13) C/(12) C ratios to those normally found for endogenous testosterone, which could prevent a positive isotopic ratio mass spectrometric (IRMS) finding in doping control. Moreover, it was investigated to what extent the preparations contained the masking agent epitestosterone, in order to lower the testosterone/epitestosterone (T/E) ratio in urinary steroid profiles. Out of 30 analyzed products, the declared ingredients differed from the actual content in 10 cases. Epitestosterone, however, could not be found in any of the products. The products displayed δ(13)C(VPDB) values between -23.6 and -29.4‰. For more than half of these products, the values were within a range reported for endogenous urinary steroids.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias , Testosterona/análise , Isótopos de Carbono/análise , Doping nos Esportes , Epitestosterona/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos
13.
J Chromatogr A ; 1218(41): 7365-70, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21907993

RESUMO

Due to the impact in the media and the requirements of sensitivity and robustness, the detection of the misuse of forbidden substances in sports is a really challenging area for analytical chemistry, where any study focused on enhancing the performance of the analytical methods will be of great interest. The aim of the present study was to evaluate the usefulness of using hydrogen instead of helium as a carrier gas for the analysis of anabolic steroids by gas chromatography-mass spectrometry with electron ionization. There are several drawbacks related with the use of helium as a carrier gas: it is expensive, is a non-renewable resource, and has limited availability in many parts of the world. In contrast, hydrogen is readily available using a hydrogen generator or high-pressure bottled gas, and allows a faster analysis without loss of efficiency; nevertheless it should not be forgotten that due to its explosiveness hydrogen must be handled with caution. Throughout the study the impact of the change of the carrier gas will be evaluated in terms of: performance of the chromatographic system, saving of time and money, impact on the high vacuum in the analyzer, changes in the fragmentation behaviour of the analytes, and finally consequences for the limits of detection achieved with the method.


Assuntos
Anabolizantes/análise , Androstanóis/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Hidrogênio/química , Androsterona/análise , Doping nos Esportes , Epitestosterona/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hélio/química , Testosterona/análise
14.
Drug Test Anal ; 3(6): 393-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21381223

RESUMO

The study of the metabolism of drugs, in particular steroids, by both in vitro and in vivo methods has been carried out in the authors' laboratory for many years. For in vitro metabolic studies, the microsomal fraction isolated from horse liver is often used. However, the process of isolating liver microsomes is cumbersome and tedious. In addition, centrifugation at high speeds (over 100 000 g) may lead to loss of enzymes involved in phase I metabolism, which may account for the difference often observed between in vivo and in vitro results. We have therefore investigated the feasibility of using homogenized horse liver instead of liver microsomes with the aim of saving preparation time and improving the correlation between in vitro and in vivo results. Indeed, the preparation of the homogenized horse liver was very simple, needing only to homogenize the required amount of liver. Even though no further purification steps were performed before the homogenized liver was used, the cleanliness of the extracts obtained, based on gas chromatography-mass spectrometry (GC-MS) analysis, was similar to that for liver microsomes. Herein, the results of the in vitro experiments carried out using homogenized horse liver for five anabolic steroids-turinabol, methenolone acetate, androst-4-ene-3,6,17-trione, testosterone, and epitestosterone-are discussed. In addition to the previously reported in vitro metabolites, some additional known in vivo metabolites in the equine could also be detected. As far as we know, this is the first report of the successful use of homogenized liver in the horse for carrying out in vitro metabolism experiments. Copyright © 2011 John Wiley & Sons, Ltd.


Assuntos
Extratos Hepáticos/metabolismo , Microssomos Hepáticos/metabolismo , Preparações Farmacêuticas/metabolismo , Androgênios/análise , Androgênios/metabolismo , Androstenos/análise , Androstenos/metabolismo , Animais , Biotransformação , Epitestosterona/análise , Epitestosterona/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Cavalos , Técnicas In Vitro , Fígado/metabolismo , Metenolona/análogos & derivados , Metenolona/análise , Metenolona/metabolismo , Estrutura Molecular , Preparações Farmacêuticas/análise , Testosterona/análogos & derivados , Testosterona/análise , Testosterona/metabolismo
15.
Endocrinol Metab Clin North Am ; 39(1): 59-73, viii-ix, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20122450

RESUMO

The Athlete Biological Passport (ABP) is an individual electronic document that collects data regarding a specific athlete that is useful in differentiating between natural physiologic variations of selected biomarkers and deviations caused by artificial manipulations. A subsidiary of the endocrine module of the ABP, that which here is called Athlete Steroidal Passport (ASP), collects data on markers of an altered metabolism of endogenous steroidal hormones measured in urine samples. The ASP aims to identify not only doping with anabolic-androgenic steroids, but also most indirect steroid doping strategies such as doping with estrogen receptor antagonists and aromatase inhibitors. Development of specific markers of steroid doping, use of the athlete's previous measurements to define individual limits, with the athlete becoming his or her own reference, the inclusion of heterogeneous factors such as the UDPglucuronosyltransferase B17 genotype of the athlete, the knowledge of potentially confounding effects such as heavy alcohol consumption, the development of an external quality control system to control analytical uncertainty, and finally the use of Bayesian inferential methods to evaluate the value of indirect evidence have made the ASP a valuable alternative to deter steroid doping in elite sports. The ASP can be used to target athletes for gas chromatography/combustion/ isotope ratio mass spectrometry (GC/C/IRMS) testing, to withdraw temporarily the athlete from competing when an abnormality has been detected, and ultimately to lead to an antidoping infraction if that abnormality cannot be explained by a medical condition. Although the ASP has been developed primarily to ensure fairness in elite sports, its application in endocrinology for clinical purposes is straightforward in an evidence-based medicine paradigm.


Assuntos
Anabolizantes/análise , Androgênios/análise , Atletas , Doping nos Esportes/prevenção & controle , Fatores Etários , Anabolizantes/administração & dosagem , Androgênios/administração & dosagem , Androstano-3,17-diol/análise , Teorema de Bayes , Biomarcadores/análise , Desidroepiandrosterona/análise , Epitestosterona/análise , Etiocolanolona/análise , Feminino , Variação Genética , Humanos , Masculino , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Valores de Referência , Fatores Sexuais , Testosterona/análise , Testosterona/fisiologia
16.
Handb Exp Pharmacol ; (195): 327-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20020372

RESUMO

The list of prohibited substances in sports includes a group of masking agents that are forbidden in both in- and out-of-competition doping tests. This group consists of a series of compounds that are misused in sports to mask the administration of other doping agents, and includes: diuretics, used to reduce the concentration in urine of other doping agents either by increasing the urine volume or by reducing the excretion of basic doping agents by increasing the urinary pH; probenecid, used to reduce the concentration in urine of acidic compounds, such as glucuronoconjugates of some doping agents; 5alpha-reductase inhibitors, used to reduce the formation of 5alpha-reduced metabolites of anabolic androgenic steroids; plasma expanders, used to maintain the plasma volume after misuse of erythropoietin or red blood cells concentrates; and epitestosterone, used to mask the detection of the administration of testosterone. Diuretics may be also misused to achieve acute weight loss before competition in sports with weight categories. In this chapter, pharmacological modes of action, intended pharmacological effects for doping purposes, main routes of biotransformation and analytical procedures used for anti-doping controls to screen and confirm these substances will be reviewed and discussed.


Assuntos
Doping nos Esportes/métodos , Inibidores de 5-alfa Redutase , Cromatografia Líquida , Diuréticos/análise , Epitestosterona/análise , Humanos , Espectrometria de Massas , Substitutos do Plasma/análise , Probenecid/análise , Uricosúricos/análise
17.
Se Pu ; 27(3): 294-8, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19803132

RESUMO

A method of gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of nine sex hormone residues, such as hexestrol, diethylstilbestrol, dienestrol, etiocholan-3alpha-ol-17-one, epitestosterone, estrone, estradiol, ethinylestradiol and estriol, in animal tissues was developed. The sex hormones were extracted with acetonitrile, then cleaned-up with a C18 solid-phase extraction (SPE) column. The microwave-assisted derivatization of the target components with N,O-bis( trimethylsilyl) trifluoroacetamide (BSTFA) and trimethylchlorosilane (TMCS) (99:1, v/v) using pyridine as solvent was performed, and then the derivatives were analyzed by GC-MS. The limits of detection were 0.1-1 microg/kg for all hormones, and the limits of quantification were 0.2-2 microg/kg. The average recoveries of sex hormones were 68.8%-93.1%. The relative standard deviations (RSDs) of inter- and intra-assay were 4.1%-22.3% and 3.1%-17.9%, respectively. The real sample tests showed this method can be used for the sensitive and accurate determination of multi-sex hormones residues in biological samples.


Assuntos
Resíduos de Drogas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hormônios Esteroides Gonadais/análise , Produtos da Carne/análise , Animais , Epitestosterona/análise , Estradiol/análise , Contaminação de Alimentos/análise , Hexestrol/análise , Suínos
18.
Forensic Sci Int ; 186(1-3): e13-6, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19243902

RESUMO

Peliosis is a rare lesion characterized by the presence of blood-filled cysts, with unknown true incidence and etiology. It has been most frequently reported to the liver (peliosis hepatis) and to other organs of the mononuclear phagocytic system, such as spleen, bone marrow and lymph nodes. However, other organs may also be affected. Its occurrence has been linked to wasting conditions such as tuberculosis, cancer, immunosuppression and the use of androgenic-anabolic steroids. Herein, we report a case of pulmonary peliosis, in a 29-year-old man who was abusing testosterone as it was proved by toxicological analysis. To our knowledge this is the third reported case of pulmonary peliosis and the first one that is not associated with peliosis of any other organ.


Assuntos
Androgênios/efeitos adversos , Cistos/induzido quimicamente , Pneumopatias/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/complicações , Testosterona/efeitos adversos , Adulto , Androgênios/análise , Cistos/patologia , Células Endoteliais/patologia , Epitestosterona/análise , Evolução Fatal , Patologia Legal , Toxicologia Forense , Humanos , Pulmão/irrigação sanguínea , Pneumopatias/patologia , Masculino , Nandrolona/análise , Testosterona/análise
19.
Talanta ; 78(2): 464-70, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-19203610

RESUMO

Testosterone is one of the most common doping drugs abused by athletes. Therefore, it is necessary to develop a sensitive and simple method to monitor testosterone and its epimer epitestosterone. An off-line immunoaffinity extraction followed by capillary electrophoresis for simultaneous determination of testosterone and epitestosterone has been described in this paper. Anti-epitestosterone monoclonal antibody which is specific to both testosterone and epitestosterone had been prepared and immobilized on a Sepharose 4B stationary phase. The immunoaffinity column was used for sample cleanup, extraction and preconcentration. After elution and reconstitution, testosterone and epitestosterone in the sample were separated and quantified by micellar electrokinetic chromatography(MEKC) using the borate buffer (200 mM borate, pH 8.7) containing 40 mM sodium cholate as a chiral selector. The immunoaffinity column was evaluated in different parameters such as the retention mechanism, selectivity, binding capacity, elution protocol, and reusability. The separation of these two compounds by MEKC was also optimized. Limit of detection for testosterone and epitestosterone were 5 and 23 ng mL(-1), respectively. It was satisfactory to apply this method to analyze testosterone and epitestosterone in spiked urine sample with the recoveries from 78% to 109%.


Assuntos
Eletroforese Capilar/métodos , Epitestosterona/análise , Testosterona/análise , Anticorpos Monoclonais , Cromatografia de Afinidade , Cromatografia Capilar Eletrocinética Micelar/métodos , Epitestosterona/urina , Humanos , Testosterona/urina
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