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Publication
Journal: Journal of chromatography
January/6/1984
Publication
Journal: Steroids
August/25/2019
Abstract
The population based Steroid Profile (SP) ratio of testosterone (T) and epitestosterone (E) has been considered as a biomarker approach to detect testosterone abuse in '80s. The contemporary Antidoping Laboratories apply the World Antidoping Agency (WADA) Technical Document (TD) for Endogenous Androgenic Anabolic Steroids (EAAS) in the analysis of SP during their screening. The SP Athlete Biological Passport (ABP) adaptive model uses the concentrations of the total of free and glucuronide conjugated forms of six EAASs concentrations and ratios measured by GC/MS. In the Antidoping Lab Qatar (ADLQ), the routine LC/MS screening method was used to quantitatively estimate the sulfate conjugated EAAS in the same analytical run as for the rest qualitative analytes. Seven sulfate EAAS were quantified for a number of routine antidoping male and female urine samples during screening. Concentrations, statistical parameters and selected ratios for the 6 EAAS, the 6 sulfate EAAS and 29 proposed ratios of concentrations from both EAAS and sulfate EAAS, which potentially used as SP ABP biomarkers, population reference limits and distributions have been estimated after the GC/MSMS analysis for EAAS and LC/Orbitrap/MS analysis for sulfate EAAS.
Publication
Journal: Journal of Pharmaceutical and Biomedical Analysis
February/14/2012
Abstract
A reliable, convenient, and sensitive on-line sweeping-MEKC sample concentration technique has been applied for the simultaneous separation of six steroids including two pairs of epimer with 10mM phosphate buffer (pH 7.0) that contains 80mM sodium dodecyl sulfate (SDS), 14mM β-cyclodextrin (β-CD), and 4% (v/v) methanol. The column length was 105cm (effective length, 90cm). Samples were hydrostatically injected for 600s. The separation was performed at ambient temperature under an applied voltage of 25kV. The external standard calibration curves of the six steroidal hormones proved good linearity (r(2)=0.9785-0.9941) within the concentration range 0.025-1.0μgmL(-1). The limit of detections of the on-line sweeping-MEKC with the ultraviolet detector at 220nm for estrone, α-estradiol, β-estradiol, androstenedione, epitestosterone, and testosterone were 10, 24, 28, 53, 73, and 11ngmL(-1) and were 240, 125, 93, 47, 32, and 200 times more sensitive than MEKC, respectively. The Saccharomyces cerevisiae mediated simultaneous stereoselective reduction of estrone and androstenedione exhibited a 100% stereoselectivity toward β-estradiol and testosterone. The accuracy and precision achieved for the spiking experiments of the sweeping-MEKC were 95-98% and less than 3.8% (RSD), respectively.
Publication
Journal: Journal of Analytical Toxicology
September/28/2014
Abstract
This article concerns the analysis of the Adverse Analytical Findings (AAFs) and the appropriate alterations made during the period 2005-2011, so that the Doping Control Laboratory of Athens (DCLA) obeys the updated World Anti-Doping Agency (WADA) List of Prohibited Substances. The % AAFs of the DCLA was compared with those of WADA-Accredited Laboratories. In 2008, the term Atypical Finding was introduced by the WADA representing a reported but inconclusive result. A characteristic example is when a testosterone-to-epitestosterone ratio is >4 followed by a negative gas chromatography/combustion/isotope ratio mass spectrometry result. In a total of about 30,000 athlete samples, 136 athletes were found with an increased testosterone/epitestosterone ratio and 43 with tetrahydrocannabinol metabolite (THCCOOH) of 427 reported AAFs. Twenty-one athletes in total were found positive with methylhexaneamine, the 11 found after a batch of 1000 samples was reprocessed. Besides, there were AAFs below their Minimum Required Performance Level (MRPL). The increasing need for higher detectability imposed new apparatus, e.g., liquid chromatography/quadrupole/time-of-flight mass spectrometry, whereas that for lowering the capital costs and reporting times led to the unification of the screening method which includes stimulants, diuretics, anabolics and other substances.
Publication
Journal: Biochemistry
June/1/1976
Abstract
Rabbit liver microsomal preparations can transfer xylose from UDP-xylose to estron, 17alpha-estradiol, and 17beta-estradiol, and, in poorer yield, to diethylstilbestrol and p-nitrophenol. No transfer of xylose to estriol, testosterone, epitestosterone or 17alpha-estradiol 3-glucuronide could be demonstrated. The xyloside of [6,7-3H]estrone which was formed by liver microsomes crystallized to constant specific activity with estrone beta-D-xylopyranoside, the chemical preparation of which is described.
Publication
Journal: Die Naturwissenschaften
November/21/1968
Publication
Journal: Zeitschrift fur Kinderheilkunde
March/19/1969
Publication
Journal: Clinical Chemistry
July/31/1968
Publication
Journal: Journal of Analytical Toxicology
July/22/2015
Abstract
A screening method for 18 frequently measured exogenous anabolic steroids and the testosterone/epitestosterone (T/E) ratio in forensic cases has been developed and validated. The method involves a fully automated sample preparation including enzyme treatment, addition of internal standards and solid phase extraction followed by analysis by liquid chromatography-tandem mass spectrometry (LC-MS-MS) using electrospray ionization with adduct formation for two compounds. Urine samples from 580 forensic cases were analyzed to determine the T/E ratio and occurrence of exogenous anabolic steroids. Extraction recoveries ranged from 77 to 95%, matrix effects from 48 to 78%, overall process efficiencies from 40 to 54% and the lower limit of identification ranged from 2 to 40 ng/mL. In the 580 urine samples analyzed from routine forensic cases, 17 (2.9%) were found positive for one or more anabolic steroids. Only seven different steroids including testosterone were found in the material, suggesting that only a small number of common steroids are likely to occur in a forensic context. The steroids were often in high concentrations (>100 ng/mL), and a combination of steroids and/or other drugs of abuse were seen in the majority of cases. The method presented serves as a fast and automated screening procedure, proving the suitability of LC-MS-MS for analyzing anabolic steroids.
Publication
Journal: Drug Testing and Analysis
May/4/2011
Abstract
The degradation processes in deficiently stored urine samples are well investigated regarding steroid concentrations and diagnostic ratios, such as the quotient of testosterone divided by epitestosterone. In contrast, nothing is known about the influence on carbon isotope ratios (CIR) by inappropriate storage conditions. In general, it is assumed that degradation, i.e. deconjugation or dehydrogenation, does not change CIR and thus CIR can be used in cases where the steroid profile turns out to be invalid. Therefore, the CIR of urinary steroids was investigated in different urine samples during the course of degradation over a time period of six months. Several steroids excreted as glucuronides (androsterone (A), etiocholanolone (E), testosterone, pregnanediol (PD) and 5α- and 5β-androstane-3α,17β-diol) or sulfo-conjugated (A, E and androst-5-ene-3β,17β-diol (5EN17b)) were investigated together with their unconjugated correspondents (A, E, PD and 5EN17b) and the main dehydrogenation products (5α- and 5β-androstane-3,17-dion and androst-4-ene-3,17-dion). For this purpose, the exiting methods for CIR determination were extended and validated. In addition, the urinary concentrations of all investigated steroids were monitored. Particular attention was paid to dehydroepiandrosterone conjugated and unconjugated together with its degradation product 3α,5-cyclo-5α-androstan-6β-ol-17-one as here the strongest influence on CIR was expected.
Publication
Journal: The Mount Sinai journal of medicine, New York
July/19/1971
Publication
Journal: Bulletin de la Societe de chimie biologique
September/18/1969
Publication
Journal: Physiological Reports
December/14/2015
Abstract
The measurement of the testosterone to epitestosterone ratio (T/E ratio) in urine is often used as a marker for testosterone administration in the doping control field. This study examines the frequencies of the different expression forms of the UGT2B17 gene, and assesses their effects on this marker in volunteer subjects. The sample for this descriptive study was composed of male and female athletes aged between 16 and 55 years old who practiced different sports disciplines. All participants underwent a sports-medical physical examination, and subsequently provided 10 urine samples consecutively over a period of 48 h. The dependent variable examined was T/E and the main independent variable was the UGT2B17 gene polymorphism. During 1 year, 1410 urine samples were obtained from 141 athletes. The frequencies of the three genotypes were as follows: wt homozygotes (ins/ins) 48.2% (n = 68), mutant homozygotes (del/del) 12.1% (n = 17), and heterozygotes (ins/del) 39.7% (n = 56). Genotype distributions varied significantly (P < 0.001) according to ethnicity, 80% of Asian subjects being homozygous for the gene deletion (del/del) compared to 6.9% of Caucasian subjects. A multivariate analysis adjusted for genotype, age, sex, and sports discipline revealed that athletes with the del/del polymorphism showed a significantly lower mean T/E than heterozygotes (ins/del). In contrast, homozygous athletes for the gene insertion (ins/ins) showed higher mean T/E ratios than heterozygotes (ins/del). UGT2B17 gene deletion has a strong influence on the T/E ratio in urine, which is the most efficient indicator of testosterone prohormone misuse. Others factors studied seem not to have such an impact. The genotyping of UGT2B17 is an important source of information for understanding steroid profiling in the doping control field; therefore it is suggested that it be included in the Athletes Biological Passport.
Publication
Journal: Chinese Journal of Chromatography (Se Pu)
June/20/2010
Abstract
A method of gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the simultaneous identification and quantification of five endogenous anabolic steroids (testosterone, epitestosterone, androsterone, etiocholanolone, dehydroepiandrosterone) in hair. After alkaline hydrolysis, the hair sample was extracted with diethyl ether, derivatized with a derivatization reagent (N-methyl-N-trimethylsilyl-trifluoroacetamid/iodotrime-thyisilane/DL-dithiothreitol, 1000:5:5, v/v/w) and detected using GC-MS/MS in the multiple-reaction monitoring mode. The one precursor/two product ion transitions for each anabolic steroids were monitored. The limits of detection for five endogenous anabolic steroids were in the range of 0.1 - 0.2 pg/mg. All analytes showed good linearity and the extraction recoveries were 74.6% - 104.5%. The inter-day and intra-day relative standard deviations (RSD) were less than 17.5%. This method has been applied to the analysis of testosterone, epitestosterone, androsterone, etiocholanolone, dehydroepiandrosterone in 80 Chinese hair samples. These data are the suitable references and the basis for the interpretation of the results from endogenous steroids abuse.
Publication
Journal: Journal of Separation Science
September/15/2014
Abstract
An online system that can perform dynamic microextraction, on-coating derivatization and desorption, and subsequent GC-MS analysis with a large-volume injection was developed. A derivatization cell as the conjunction of the online system was developed for the online extraction and derivatization. To evaluate the feasibility of the online system, methyltestosterone molecularly imprinted polymer filaments (MIPFs) were prepared for the selective online extraction of five androgenic steroids, namely, methyltestosterone, testosterone, epitestosterone, nandrolone, and metandienone. Under the optimized conditions, the detection limits of testosterone and epitestosterone were 0.09 and 0.12 μg/L, respectively, which were under the minimum required performance limits between 2 and 10 μg/L from the World Anti-Doping Agency. The detection limits of the other three androgenic steroids were varied from 0.04 to 0.18 μg/L. Finally, the MIPFs-GC-MS method was applied for the determination of androgenic steroids in urine, and satisfactory recovery (78.0-96.9%) and reproducibility (3.2-8.9%) were obtained. The proposed online coupling system offers an attractive alternative for hyphenation to GC instruments and could also be extended to other adsorptive materials.
Publication
Journal: Fertility and Sterility
October/19/1967
Publication
Journal: Laboratornoe delo
February/13/1986
Publication
Journal: Drug Testing and Analysis
June/29/2021
Abstract
In order to detect the misuse of testosterone (T) or boldenone (Bo) in doping control analysis, the confirmation of atypical findings employing the determination of carbon isotope ratios (CIR) is mandatory for issuing adverse analytical findings. Elevated concentrations of T (or elevated T/epitestosterone ratios) may result from confounding factors such as ethanol intake, and the presence of low urinary concentrations of Bo can originate from endogenous or urinary in situ production of small amounts of the steroid. As pharmaceutical preparations of Bo and T are generally depleted in 13 C, their CIR differ significantly from the 13 C-enriched endogenous steroids. Some rare cases have been reported on pharmaceutical preparations showing 13 C-enriched isotope ratios that complicate the current application of CIR in sports drug testing. Therefore, the CIR of a subset of n = 157 T preparations and n = 39 Bo preparations seized in Switzerland and Germany between 2013 and 2018 was analyzed in order to estimate the possible impact of steroid preparations showing 13 C-enriched isotope ratios on the current approach to detect their misuse. All investigated Bo preparations showed CIR in the expected range between - 26.7 and -30.3 ‰. Within the T samples, 95 % showed the expected values below -26 ‰ while 6 samples fall between -25 and -26 ‰ and one sample was indistinguishable from endogenously produced T with a CIR of -23.3 ‰.
Keywords: Carbon isotope ratio; boldenone; doping; isotope ratio mass spectrometry; testosterone.
Publication
Journal: Journal of Chromatography A
September/20/2016
Abstract
The aim of this study was to assess the retention and selectivity of a cocktail of 10 substrates of uridine diphosphate glucuronosyltransferase enzymes (UGTs) and their respective glucuronides using four chromatographic approaches. For this purpose, seven different stationary phases were employed in reversed phase liquid chromatography (RPLC), two in hydrophilic interaction liquid chromatography (HILIC), one in aqueous normal phase chromatography (ANPC) and four in subcritical fluid chromatography (SFC). Highly orthogonal separations were achieved with these chromatographic modes. Hydrophobic interactions mainly governed the retention of the substrates and their polar glucuronides in RPLC despite the use of different chemical stationary phase bonding, involving additional possible interactions. In ANPC, atypical separations and poor peak shapes were observed with the selected compounds. In HILIC and SFC conditions, the metabolites were more retained than the substrates because of the polarity increase related to the glucuronic acid moiety. For the latter, a very high proportion of organic solvent (up to 80%) was required to elute the glucuronides that often displayed poor peak shapes. Finally, the selectivity of nine chromatographic systems was compared for the separation of isomeric and diastereoisomeric compounds. The stationary phases used in RPLC mode were more selective towards the two positional isomers of morphine glucuronides since they possess distinct lipophilicity. HILIC and SFC columns were found to be promising for the separation of a critical diastereoisomers pair, namely epitestosterone-glucuronide and testosterone-glucuronide.
Publication
Journal: Rapid Communications in Mass Spectrometry
March/31/2008
Abstract
It is established that bovine urine can result positive for boldenone and androstadienedione in consequence of faecal contamination. The simple transfer of steroids to urine is one minor aspect of faecal contamination. A high de novo production of steroids in faeces after deposition and in faeces-contaminated urine is almost certainly due to microbial activity, although the precursor compounds and transformations leading to the presence of these illegal steroids are unclear. We developed a simple in vitro method - incubation of faecal matter suspended in 0.9% saline - to induce steroid transformations in faeces, and analyzed the products by liquid chromatography/tandem mass spectrometry, without the need for prior extraction. Norethandrolone was the internal standard. The linearity (R(2): 0.987-0.999), sensitivity (LODs: 0.3 to 1.0 ng/mL; LOQs: 1.0 to 3.0 ng/mL), precision (intra-day CVs: 2.6-8.2; inter-day CVs: 4.5-11.5) and accuracy (percentage recovery: 89-120%) were calculated for the studied steroids. Androstenedione, androstadienedione, alpha- and beta-boldenone, testosterone and epitestosterone transformations were investigated. Mutual interconversion of steroids was observed, although 17beta-hydroxy steroids had low stability compared with 17alpha-hydroxy and 17-keto steroids. The results suggest that this simple in vitro system may be an effective way of studying hormone transformations in faeces and, after analogue studies, in faeces-contaminated urine.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
November/10/2020
Abstract
Conjugation with glucuronic acid is one of the major metabolic reactions in human steroid hormone catabolism. Recently, increasing interest has been raised concerning the biological roles of steroid glucuronides. We have therefore developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of 15 urinary steroid hormone glucuronides in human urine: androsterone glucuronide (An-G), etiocholanolone glucuronide (Etio-G), epiandrosterone glucuronide (epiAn-G), dihydrotestosterone glucuronide (DHT-G), dehydroepiandrosterone glucuronide (DHEA-G), testosterone glucuronide (T-G), epitestosterone glucuronide (epiT-G), estrone glucuronide (E1-3 G), 17β-estradiol 17-glucuronide (E2-17 G), 17β-estradiol 3-glucuronide (E2-3 G), estriol 16-glucuronide (E3-16 G), pregnenolone glucuronide (Preg-G), tetrahydro-11-deoxycorticosterone 3-glucuronide (THDOC-3 G), cortisol 21-glucuronide (F-G) and pregnanediol glucuronide (PD-G). Sample workup included protein precipitation and solid phase extraction. Internal standards were used to correct for the loss of analytes during sample preparation and analysis. The method showed good linearity (R2≥0.99) and recovery ranged from 89.6 % to 113.8 %. Limit of quantification ranged from 1.9 nmol/L for F-G to 21.4 nmol/L for An-G. Intra-day and inter-day accuracy and precision were below 15 % for all quality controls. The method was successfully applied to 67 urine samples from children and adolescents in whom total concentrations of free and conjugated steroids had been previously determined by GC-MS after enzymatic hydrolysis. Free and sulfated steroids were also measured by LC-MS/MS. In general, the sums of the respective glucuronidated, sulfated and free forms of an analyte corresponded well with its total amount determined after enzymatic hydrolysis by GC-MS. Regarding the most prominent steroid metabolites, the total mean levels of androsterone and etiocholanolone showed an increase up to 5820.0 nmol/L and 4017.8 nmol/L in the group of 15-20 year-old children, respectively. Glucuronide conjugates (4374.3 nmol/L and 3588.5 nmol/L, respectively) dominated. DHEA was excreted mostly as sulfate (0-1 month of age: 184.5 nmol/L; 15-20 years of age: 1618.4 nmol/L) in all age groups. Cortisol was present predominantly as sulfate (mean: 173.8 nmol/L) in newborns. Levels of sulfated cortisol decreased with age, its glucuronidated form increased. The levels of free cortisol were relatively constant throughout childhood. Sex hormones were preferably excreted as glucuronides. In general, steroid hormone metabolites were conjugated to various extents with glucuronic acid or sulfuric acid and their ratio changed over lifetime.
Keywords: Liquid chromatography; Mass spectrometry; Steroid; Steroid glucuronide; Urine.
Publication
Journal: Voprosy Onkologii
September/24/1979
Abstract
To obtain more insight into the problem on the concentration of active androgens in the male organism, the diurnal elimination of testosterone, epitestosterone and estrogens in the urine of male patients with cancer of the lung, urinary bladder, larynx and prostate (321 patients), in stage II--III, was estimated. In patients with cancer of the lung and urinary bladder testosterone was found to be lowered, while total estrogens--lowered or unchanged irrespective of age, a relative hyperestrogenization being noted in them. Contrary, in cancer of the larynx and prostate the male hormones were predominating over female ones (hyperandrogenization). In all the examined patients irrespective of the tumor process localization a relative or even absolute predominance of epitestosterone over testosterone was evident.
Publication
Journal: Endocrine Regulations
December/7/1994
Abstract
Epitestosterone has been shown previously to counteract the testosterone activity in some experimental models. In the present study the activity of epitestosterone in an in vitro model of human LNCaP/FCS prostate cells and in vitro in Dunning R 3327-GH rat prostate carcinoma was tested. In LNCaP/FGC cells cultivated with fetal calf serum (FCS) treated with dextran-coated charcoal epitestosterone displayed rather androgenic than antiandrogenic properties, whereas the cultivation with native FCS resulted in a very weak inhibition of tumour cell growth with epitestosterone in higher concentration. The growth of Dunning R 3327-GH carcinoma of prostate was very weakly enhanced by epitestosterone alone as late as at the end of the 5-week experiment. Epitestosterone did not significantly inhibit the testosterone stimulated tumour growth.
Publication
Journal: Cancer
October/31/1998
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