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1.
Drug Test Anal ; 7(7): 609-18, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25284752

RESUMO

Twenty-four products suspected of containing anabolic steroids and sold in fitness equipment shops in the United Kingdom (UK) were analyzed for their qualitative and semi-quantitative content using full scan gas chromatography-mass spectrometry (GC-MS), accurate mass liquid chromatography-mass spectrometry (LC-MS), high pressure liquid chromatography with diode array detection (HPLC-DAD), UV-Vis, and nuclear magnetic resonance (NMR) spectroscopy. In addition, X-ray crystallography enabled the identification of one of the compounds, where reference standard was not available. Of the 24 products tested, 23 contained steroids including known anabolic agents; 16 of these contained steroids that were different to those indicated on the packaging and one product contained no steroid at all. Overall, 13 different steroids were identified; 12 of these are controlled in the UK under the Misuse of Drugs Act 1971. Several of the products contained steroids that may be considered to have considerable pharmacological activity, based on their chemical structures and the amounts present. This could unwittingly expose users to a significant risk to their health, which is of particular concern for naïve users.


Assuntos
Anabolizantes/análise , Suplementos Nutricionais/análise , Dopagem Esportivo , Saúde Pública/tendências , Esteroides/análise , Levantamento de Peso , Cromatografia Líquida/métodos , Cristalografia por Raios X , Suplementos Nutricionais/efeitos adversos , Fatores de Risco , Esteroides/efeitos adversos , Espectrometria de Massas em Tandem/métodos
2.
Drug Test Anal ; 6(6): 506-15, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24574323

RESUMO

The classic approach of controlled volunteer studies to study drug metabolism is difficult or impossible to undertake for novel psychoactive substances (NPS), as there is generally very limited information available to allow appropriate dose finding and safety. A viable and powerful alternative is the identification and characterization of phase I and II metabolites of such drugs by examining the concordance of data gathered from analysis of microsomal incubates with that from analysis of specimens collected from individuals with analytically confirmed use of NPS. Liquid chromatography-high resolution mass spectrometry provides the ability to reliably identify such metabolites. We used this technique here to study the metabolism of the ketamine analogue methoxetamine. A large number of metabolites were identified in the in vitro studies including normethoxetamine, O-desmethylmethoxetamine, dihydromethoxetamine, dehydromethoxetamine and several structural isomers of hydroxymethoxetamine and hydroxynormethoxetamine. pH dependent liquid-liquid extraction was used to discriminate phenolic from alcoholic metabolites. Phase II glucuronide conjugates included those of O-desmethylmethoxetamine, O-desmethylnormethoxetamine and O-desmethylhydroxymethoxetamine. The majority of these phase I and II metabolites were confirmed to be present in urine collected from three individuals presenting with acute methoxetamine toxicity.


Assuntos
Cromatografia Líquida/métodos , Cicloexanonas/metabolismo , Cicloexilaminas/metabolismo , Drogas Ilícitas/metabolismo , Espectrometria de Massas/métodos , Humanos , Concentração de Íons de Hidrogênio , Extração Líquido-Líquido
3.
Drug Test Anal ; 6(3): 194-201, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24339374

RESUMO

A major toxicological challenge is distinguishing whether morphine in urine, in the absence of 6-monoacetylmorphine (6-MAM), originates from 'street' heroin use or poppy seed ingestion. Manufacturing byproducts from the synthesis of illicit heroin include those that originate from the reaction of acetic anhydride with the alkaloid impurity, thebaine, which undergoes skeletal rearrangement, resulting in compounds with a 2-(N-methylacetamido)ethyl side-chain. The hypothesis that the tertiary amide in this side-chain is resistant to endogenous hydrolysis was supported from in-vitro experiments; a glucuronide metabolite (designated 'ATM4G') was identified that may be used as a marker of 'street' heroin administration. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis for this metabolite was then performed on selected urine specimens from 22 known heroin users, these being negative on routine testing for 6-MAM by gas chromatography-mass spectrometry (GC-MS), using the generally applied reporting threshold of 10 ng/mL, but positive for the presence of morphine. Peaks corresponding to the retention time for the metabolite marker were clearly observed for 16 of the 22 samples, with variations of the ratios of its three dependent ions being within ± 30% of that produced in vitro. Conversely, 6-MAM was detected in only 3 samples, but at concentrations <1 ng/mL. Such a high frequency for the presence of the metabolite marker in urine, in the absence of 6-MAM, is noteworthy and suggests that detection of this metabolite may offer an important advance in forensic toxicology, allowing the development of a new and more definitive test for heroin abuse and thus a potential solution to the so-called 'poppy seed defense'.


Assuntos
Heroína/urina , Derivados da Morfina/urina , Papaver , Detecção do Abuso de Substâncias/métodos , Tebaína/urina , Acetilação , Adulto , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas , Heroína/análise , Heroína/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Derivados da Morfina/análise , Derivados da Morfina/metabolismo , Papaver/química , Sementes/química , Espectrometria de Massas em Tandem/métodos , Tebaína/análise , Tebaína/metabolismo
4.
Drug Test Anal ; 4(12): 962-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22761127

RESUMO

The accuracy and precision of gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) measurements are highly dependent on analyte purity. Reliable analysis of urinary steroids for doping control therefore requires extensive and time-consuming sample preparation (i.e. liquid chromatography fraction collection) prior to GC-C-IRMS analysis. The use of two-dimensional GC (GC-GC) with heart-cutting (Deans Switch) as a possible approach to reduce the sample purification required for IRMS analysis is described herein. The system uses a low thermal mass oven (LTM) incorporated into an existing GC-C-IRMS system. GC-GC allowed the use of a cyanopropyl/phenyl column in the first dimension to optimize the separation of underivatized steroids, while a phenyl-methylpolysiloxane column in the second dimension focuses the selectively cut analytes into narrower peaks for more sensitive and reliable MS analysis. In addition, to confirm analyte identity, eluent from the second GC was split, with 20 % entering a scanning MS, and 80 % flowing to the IRMS. As a proof concept, the developed method was then used to analyze a single spot urine (5 ml) from an individual receiving T therapy (2 × 50 mg sachets of Testogel(®)). The T delta value (-27.8 ‰, [T] = 38 ng/ml) was clearly distinct from 11-ketoetiocholanolone (-22.5 ‰) (used as an endogenous reference compound (ERC)), indicating T as being of exogenous origin. The simultaneous analysis by the scanning MS yielded a full scan mass spectrum of the same chromatographic peak, thus confirming the peak to be T.


Assuntos
Anabolizantes/urina , Isótopos de Carbono/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Anabolizantes/administração & dosagem , Biomarcadores/urina , Calibragem , Desenho de Equipamento , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Limite de Detecção , Técnicas Analíticas Microfluídicas , Substâncias para Melhoria do Desempenho/administração & dosagem , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/instrumentação , Detecção do Abuso de Substâncias/normas , Testosterona/administração & dosagem
6.
Drug Test Anal ; 3(7-8): 479-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21748859

RESUMO

Due to its closed ring system, 2-aminoindane is a conformationally rigid analogue of amphetamine. Internet websites offering synthetic compounds as 'research chemicals' have recently been advertising 5,6-methylenedioxy-2-aminoindane (MDAI), 5, 6-methylenedioxy-N-methyl-2-aminoindane (MDMAI), 5-iodo-2-aminoindane (5-IAI), and 5-methoxy-6-methyl-2-aminoindane (MMAI). The chemistry, pharmacology, and toxicological aspects of this new class of psychoactive substances are reviewed, as these could become the next wave of 'legal highs'.


Assuntos
Drogas Ilícitas/química , Drogas Ilícitas/farmacologia , Indanos/química , Indanos/farmacologia , Neurotransmissores/química , Neurotransmissores/farmacologia , Aminas/síntese química , Aminas/química , Aminas/farmacologia , Animais , Humanos , Drogas Ilícitas/síntese química , Indanos/síntese química , Neurotransmissores/síntese química
7.
Br J Pharmacol ; 154(3): 502-21, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18500378

RESUMO

Athletes and bodybuilders have recognized for several decades that the use of anabolic steroids can promote muscle growth and strength but it is only relatively recently that these agents are being revisited for clinical purposes. Anabolic steroids are being considered for the treatment of cachexia associated with chronic disease states, and to address loss of muscle mass in the elderly, but nevertheless their efficacy still needs to be demonstrated in terms of improved physical function and quality of life. In sport, these agents are performance enhancers, this being particularly apparent in women, although there is a high risk of virilization despite the favourable myotrophic-androgenic dissociation that many xenobiotic steroids confer. Modulation of androgen receptor expression appears to be key to partial dissociation, with consideration of both intracellular steroid metabolism and the topology of the bound androgen receptor interacting with co-activators. An anticatabolic effect, by interfering with glucocorticoid receptor expression, remains an attractive hypothesis. Behavioural changes by non-genomic and genomic pathways probably help motivate training. Anabolic steroids continue to be the most common adverse finding in sport and, although apparently rare, designer steroids have been synthesized in an attempt to circumvent the dope test. Doping with anabolic steroids can result in damage to health, as recorded meticulously in the former German Democratic Republic. Even so, it is important not to exaggerate the medical risks associated with their administration for sporting or bodybuilding purposes but to emphasize to users that an attitude of personal invulnerability to their adverse effects is certainly misguided.


Assuntos
Anabolizantes/farmacologia , Dopagem Esportivo , Esteroides/farmacologia , Anabolizantes/efeitos adversos , Animais , Desempenho Atlético/fisiologia , Feminino , Humanos , Masculino , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Esteroides/efeitos adversos
8.
Hum Reprod ; 19(11): 2658-67, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15333595

RESUMO

BACKGROUND: Combined testosterone and progestogen preparations are a promising approach to male hormonal contraception. We investigated the effect of s.c. etonogestrel with depot testosterone on spermatogenesis in normal men over a period of 48 weeks. METHODS: Fifteen healthy men received three s.c. 68 mg etonogestrel implants. Testosterone pellets (400 mg) were administered at 12 weekly intervals. RESULTS: Nine men completed 48 weeks of treatment. Four subjects chose to discontinue after 6 months, one man withdrew from the study early for personal reasons and one was withdrawn due to illness. Sperm concentrations of <1 x 10(6)/ml were achieved in all men by 16 weeks of treatment. All men became azoospermic, although the time to achieve this varied from 8 to 28 weeks. Azoospermia was maintained in eight of the nine men treated for 48 weeks, one subject showing partial recovery from 40 weeks. Testosterone levels remained in the physiological range throughout. Treatment did not result in weight gain, change in body composition or decline in high-density lipoprotein cholesterol concentrations. CONCLUSIONS: The combination of three etonogestrel implants with depot testosterone results in rapid and consistent suppression of spermatogenesis. This can be maintained for up to 1 year and may therefore be a suitable approach for a long-acting male hormonal contraceptive.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/efeitos adversos , Desogestrel/administração & dosagem , Desogestrel/efeitos adversos , Oligospermia/induzido quimicamente , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Adolescente , Adulto , Composição Corporal/efeitos dos fármacos , Desogestrel/sangue , Relação Dose-Resposta a Droga , Implantes de Medicamento , Epitestosterona/sangue , Epitestosterona/urina , Hormônio Foliculoestimulante/sangue , Hemoglobinas/análise , Humanos , Inibinas/sangue , Lipídeos/sangue , Hormônio Luteinizante/sangue , Masculino , Oligospermia/metabolismo , Comportamento Sexual/efeitos dos fármacos , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Testosterona/sangue
10.
J Mol Endocrinol ; 30(2): 239-52, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12683946

RESUMO

Metabolism of the human chorionic gonadotrophin (hCG)- and LHbeta-subunits (hCGbeta, LHbeta) terminates with the urinary excretion of core fragment (hCGbetacf, LHbetacf) molecules that retain antigenic shape and constituent N-linked carbohydrate moieties. We have previously demonstrated the resolved mass spectra of hCGbetacf, from which the carbohydrate moieties present at two N-linked glycosylation sites were identified. LHbetacf was subjected to the same mass spectrometric analysis. As LHbeta shares 82% homology with hCGbeta but possesses only one glycosylation consensus site a simpler spectral fingerprint of LHbetacf glycoforms was expected. LHbetacf was reduced with dithiothreitol and analysed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Glycoforms were predicted by subtracting the peptide mass from the m/z values of the observed peaks and then sequentially subtracting the masses of the monosaccharide residues of hCGbeta N-linked carbohydrates reported in the literature. The mass spectra of LHbetacf revealed a broad single peak ranging from m/z 8700 to 10 700. Following reduction, this peak was replaced by a set of partially resolved peaks between m/z 4130 and 5205 corresponding to glycosylated forms of the peptide LHbeta6-40. A peak at m/z 4252.2 corresponded to the non-glycosylated peptide LHbeta55-93. Remaining peaks indicated that the pooled sample comprised a wide set of glycoforms, contained LHbetacf with two N-linked carbohydrate moieties and indicated evidence of further glycosylation due to amino acid substitution in polymorphic variants. This is evidence that a single nucleotide polymorphism alters the post-translational modification of a protein and hence its structural phenotype.


Assuntos
Hormônio Luteinizante Subunidade beta/química , Fragmentos de Peptídeos/química , Hipófise/metabolismo , Polimorfismo Genético , Isoformas de Proteínas/química , Processamento de Proteína Pós-Traducional , Configuração de Carboidratos , Sequência de Carboidratos , Glicosilação , Humanos , Hormônio Luteinizante Subunidade beta/genética , Hormônio Luteinizante Subunidade beta/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Ann N Y Acad Sci ; 965: 399-409, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12105115

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA) has been reported to cause hyponatraemia, which appears to result from inappropriate secretion of the antidiuretic hormone arginine vasopressin (AVP). After administration of a low dose of (R,S)-MDMA (40 mg) to eight healthy drug-free male volunteers, concentrations of AVP in plasma increased significantly at 1, 2, and 4 hours. Although no relation between plasma MDMA and AVP was found on an examination of the entire data set over the 24-hour study period, a statistically significant negative correlation was observed at 1 hour. As this occurred at a time when both AVP and MDMA concentrations were rising, it was postulated that a metabolite, or metabolites, could primarily be responsible for the increase in AVP. To test this hypothesis we examined the effect of MDMA and five of its metabolites, in the dose range 0.1-1,000 nM, on AVP release from the isolated rat hypothalamus. All compounds tested were found to increase AVP release (using 10 nM and 1,000 nM concentrations), with 4-hydroxy-3-methoxymethamphetamine (HMMA), the major metabolite of MDMA, being the most potent, and 3,4-dihydroxymethamphetamine (DHMA) the least potent. Each compound (1,000 nM), with the exception of DHMA, also enhanced the response to 40-mM potassium stimulation. Our findings confirm that metabolites of MDMA, in addition to the parent drug, contribute to AVP secretion in vitro. Further work will demonstrate whether this is also true in vivo.


Assuntos
Arginina Vasopressina/metabolismo , Hipotálamo/fisiologia , N-Metil-3,4-Metilenodioxianfetamina/análogos & derivados , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Animais , Arginina Vasopressina/sangue , Relação Dose-Resposta a Droga , Hipotálamo/efeitos dos fármacos , Técnicas In Vitro , Cinética , Masculino , N-Metil-3,4-Metilenodioxianfetamina/sangue , Ratos , Ratos Wistar , Estereoisomerismo
12.
Hum Reprod ; 17(6): 1490-501, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12042267

RESUMO

BACKGROUND: Effective hormonal male contraception requires a high prevalence of spermatogenic suppression, which has proved particularly difficult in Caucasian populations. We have investigated the combination of oral desogestrel with depot testosterone in Caucasian and Chinese men. METHOD: Thirty men in Edinburgh and 36 men in Shanghai received 150 or 300 microg desogestrel p.o. daily for 24 weeks with 400 mg testosterone pellets s.c. on day 1 and at 12 weeks. RESULTS: Eight men withdrew before completing 24 weeks treatment. Testosterone concentrations remained within the normal range. Spermatogenesis was profoundly suppressed in all men. Azoospermia was achieved by a higher proportion of men in the 300 microg desogestrel group: 28/28 men versus 22/31 men (P < 0.05). All Caucasian men in the 150 microg group achieved sperm concentrations of < 1 x 10(6)/ml whereas three men in the Shanghai group maintained sperm concentrations of > 3 x 10(6)/ml. Fifteen men continued on this regimen for a subsequent 24 weeks: all remained azoospermic for the duration of treatment. High-density lipoprotein cholesterol fell by 15% in Caucasian men, but was unchanged in the Chinese men; both groups showed some weight gain. CONCLUSION: This combination of oral desogestrel with depot testosterone maintains physiological testosterone concentrations with consistent suppression of spermatogenesis to azoospermia in both Caucasian and Chinese men and therefore has many of the properties necessary for a contraceptive preparation for men.


Assuntos
Desogestrel/administração & dosagem , Bloqueadores de Espermatogênese/administração & dosagem , Espermatogênese/efeitos dos fármacos , Testosterona/administração & dosagem , Administração Oral , Adulto , Afeto/efeitos dos fármacos , Povo Asiático , Desogestrel/efeitos adversos , Implantes de Medicamento , Epitestosterona/urina , Gonadotropinas Hipofisárias/metabolismo , Humanos , Inibinas/metabolismo , Lipídeos/sangue , Masculino , Oligospermia/induzido quimicamente , Estudos Prospectivos , Globulina de Ligação a Hormônio Sexual/metabolismo , Contagem de Espermatozoides , Bloqueadores de Espermatogênese/efeitos adversos , Testosterona/metabolismo , População Branca
13.
J Pharm Pharmacol ; 53(10): 1357-63, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11697543

RESUMO

The aim of this investigation was to examine the effect of 3,4-methylenedioxymethamphetamine (MDMA) administration on arginine vasopressin (AVP) release. (R,S)-MDMA (40 mg) was administered to eight normally hydrated healthy male volunteers (22-32 years) and blood samples were collected up to 24 h. Plasma was assayed for AVP and cortisol by radioimmunoassays, and for MDMA and the N-demethylated metabolite, MDA, by gas chromatography-mass spectrometry. Sodium concentrations and osmolality were also determined. Plasma AVP increased in all subjects after MDMA administration and a significant negative correlation was observed between concentrations of AVP and both single and total enantiomer MDMA at 1 h (r < -0.91, P < 0.01). This had disappeared by 2 h (P > 0.7). Compared with basal values, no significant change was observed for osmolality or cortisol at 1 h after drug administration. In conclusion, plasma AVP concentrations increase after MDMA administration, but the increase is not part of a generalized stress response since cortisol did not increase concurrently. A significant negative correlation between plasma MDMA and AVP was observed soon after administration. The possibility that a pharmacological effect of MDMA is primarily mediated via one or more metabolites, rather than by the parent drug, should be considered.


Assuntos
Arginina Vasopressina/metabolismo , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Adulto , Biotransformação , Alucinógenos/sangue , Alucinógenos/farmacocinética , Humanos , Hidrocortisona/sangue , Masculino , N-Metil-3,4-Metilenodioxianfetamina/sangue , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética , Concentração Osmolar , Sódio/sangue , Estereoisomerismo
14.
Clin Chem ; 46(11): 1796-803, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11067815

RESUMO

BACKGROUND: Metabolism of human chorionic gonadotropin (hCG) in the serum and kidney yields the terminal urinary product hCG beta-core fragment (hCGbetacf), comprising two disulfide-linked peptides (beta6-beta40 and beta55-beta92) of which one (beta6-beta40) retains truncated N-linked sugars. Hyperglycosylated hCGbetacf may indicate choriocarcinoma or Down syndrome, but the glycosylation profile of hCGbetacf has not been thoroughly evaluated. METHODS: hCGbetacf, purified from pregnancy urine, was reduced by "on-target" dithiothreitol (DTT) reduction and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The mass ([M+H](+)) of the primary sequence of the glycosylated peptide beta6-beta40 was subtracted from the m/z values of the discrete peaks observed to give the masses of the carbohydrate moieties. Carbohydrate structure was predicted by sequentially subtracting the masses of the monosaccharide residues corresponding to N-linked carbohydrates of the hCG beta-subunit reported in the literature. RESULTS: Mass spectra of hCGbetacf revealed a broad triple peak at m/z 8700-11300. After reduction, the triple peak was replaced by a discrete set of peaks between m/z 4156 and 6354. A peak at m/z 4156.8 corresponded to the nonglycosylated peptide (beta55-beta92). The remaining nine peaks indicated that urinary hCGbetacf comprises a set of glycoforms smaller and larger than the trimannosyl core. CONCLUSIONS: hCGbetacf comprises a wider set of glycoforms than reported previously. Peaks of highest mass indicate evidence of hyperglycosylated carbohydrate moieties. The data support previous reports that hCGbetacf oligosaccharides lack sialic acid and galactose residues. No indication was found of a beta6-beta40 peptide that was entirely devoid of carbohydrate.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/química , Fragmentos de Peptídeos/química , Sequência de Carboidratos , Gonadotropina Coriônica Humana Subunidade beta/urina , Feminino , Glicosilação , Humanos , Dados de Sequência Molecular , Oligossacarídeos/análise , Fragmentos de Peptídeos/urina , Gravidez , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Clin Endocrinol (Oxf) ; 50(5): 661-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10468933

RESUMO

OBJECTIVE: The ratio of urinary testosterone (T) to epitestosterone (EpiT) is used to detect T abuse in sport. Also, plasma or urinary concentrations of EpiT have been measured to assess testicular steroidogenesis during hormonal male contraception. Further investigations are required to evaluate the relative contributions of the testis and adrenal to EpiT production. To this purpose, we have compared basal urinary EpiT glucuronide and plasma EpiT and the response to synthetic adrenocorticotrophic hormone (ACTH) stimulation between eugonadal and hypogonadal men. DESIGN AND SUBJECTS: The basal urinary excretion rate of EpiT glucuronide was determined in 34 eugonadal men. Six men, clinically diagnosed as hypogonadal, and 6 out of the 34 eugonadal men previously described, received an intramuscular injection of synthetic ACTH depot (1 mg) at 0800 h on two consecutive days. Blood samples were collected prior to and then at 1.5, 8, 24, 25.5, 32 and 48 h with respect to the first administration (0 h). 24-h urine specimens were collected from 0800 h on days 1 and 2 (baseline) and 3 and 4 (stimulation). MEASUREMENTS: Plasma EpiT, T and cortisol were measured by RIA and urinary EpiT and T, following glucuronide hydrolysis, by gas chromatography-mass spectrometry (extract combines aglycones with a minor amount of urinary free steroids). RESULTS: Basal excretion rates of EpiT glucuronide in eugonadal men (range: 62-751 nmol/24 h) were considerably greater than in hypogonadal men (range: 3-34 nmol/24 h). Mean basal plasma EpiT in eugonadal men (1.32 +/- 0.08 nmol/l) were greater than in hypogonadal men (0.68 +/- 0.04 nmol/l). In each group, synthetic ACTH stimulation increased plasma cortisol 4-fold. In eugonadal men, plasma and urinary EpiT were unchanged whereas plasma and urinary T glucuronide decreased in response to ACTH. In hypogonadal patients, ACTH increased plasma and urinary EpiT while plasma T remained unchanged. CONCLUSION: The testes are the major source of epitestosterone, the adrenal contribution being relatively modest. Following adrenal stimulation, urinary epitestosterone glucuronide increases considerably in hypogonadal men but this increase is masked in eugonadal men because testicular production is probably suppressed by the ACTH-induced rise in cortisol. Activation of the adrenal cortex results in no change or only a small decrease in the urinary T/EpiT ratio in eugonadal men.


Assuntos
Glândulas Suprarrenais/fisiopatologia , Cosintropina , Epitestosterona/urina , Hipogonadismo/fisiopatologia , Detecção do Abuso de Substâncias , Glândulas Suprarrenais/efeitos dos fármacos , Adulto , Estudos de Casos e Controles , Epitestosterona/sangue , Humanos , Hidrocortisona/sangue , Hipogonadismo/sangue , Hipogonadismo/urina , Masculino , Valor Preditivo dos Testes , Testosterona/sangue
16.
Clin Chem ; 45(7): 1058-69, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10388483

RESUMO

BACKGROUND: Little is known concerning the enantioselective disposition of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) in humans. In addition, the potential of utilizing the stereochemical composition of an analyte in biological media for forensic purposes requires investigation. METHODS: The enantiomers of MDMA and its demethylated metabolite, 3,4-methylenedioxyamphetamine (MDA), present in plasma and urine extracts were derivatized with (-)-(R)-alpha-methoxy-alpha-trifluoromethylphenylacetyl chloride and analyzed by gas chromatography-mass spectrometry and gas chromatography, respectively. The enantioselective disposition of MDMA and MDA was determined following oral administration of racemic MDMA (40 mg) to eight male volunteers. RESULTS: The plasma concentrations of (R)-MDMA exceeded those of the S-enantiomer [ratio R:S of the area under the curve (AUC), 2.4 +/- 0.3], and the plasma half-life of (R)-MDMA (5.8 +/- 2.2 h) was significantly longer than that of the S-enantiomer (3.6 +/- 0.9 h). The majority of the recovered material in urine was excreted within 24 h after dosing, with the recovery of (R)-MDMA (21.4% +/- 11.6%) being significantly greater than that of (S)-MDMA (9.3% +/- 4.9%), and with (S)- and (R)-MDA accounting for 1.4% +/- 0.5% and 1.0% +/- 0.3% of the dose, respectively. Mathematical modeling of plasma enantiomeric composition vs sampling time demonstrated the applicability of using stereochemical data for the prediction of time elapsed after drug administration. CONCLUSIONS: Analytical methods for determining the enantiomeric composition of MDMA and MDA in plasma and urine were developed. The disposition of MDMA in humans is stereoselective, with the more active S-enantiomer having a reduced AUC and shorter half-life than (R)-MDMA. The determination of stereochemical composition may be applicable for forensic purposes.


Assuntos
Alucinógenos/farmacocinética , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética , Administração Oral , Adulto , Cromatografia Gasosa-Espectrometria de Massas , Alucinógenos/sangue , Alucinógenos/urina , Humanos , Masculino , N-Metil-3,4-Metilenodioxianfetamina/sangue , N-Metil-3,4-Metilenodioxianfetamina/urina , Análise de Regressão , Reprodutibilidade dos Testes , Estereoisomerismo
17.
J Mol Endocrinol ; 22(2): 185-92, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10194521

RESUMO

The free beta-subunit of human chorionic gonadotrophin (hCGbeta) is well recognised as a product of many epithelial tumours. Recently, it has been shown that this ectopic production may have a functional relationship to tumour growth. The growth-promoting activity of hCGbeta may be explained by its structural similarity to a family of growth factors which all contain the same distinct topological fold known as the cystine-knot motif. Since the other members of this family all exhibit their activities as homo- and heterodimers, it is possible that the same may be true for hCGbeta. Using size-exclusion chromatography, low stringency SDS-PAGE and matrix assisted laser desorption/ionisation (MALDI) time-of-flight (TOF) mass spectrometry (MS) we have shown that pure preparations of hCGbeta contain hCGbetabeta homodimers. Size-exclusion chromatography revealed asymmetric elution profiles with a forward peak corresponding to the size-exclusion characteristic of a globular protein with an approximate mass of 44-54 kDa and a late shoulder centered around an elution position expected for a globular protein of approximately 29 kDa. Two immunoreactive hCGbeta species, of approximately 32 and 64 kDa, were clearly resolved by SDS-PAGE and Western blotting. When analysed by MALDI-TOF MS a |mf23 kDa monomer and a |mf46 kDa dimer were identified. Formation of hCGbetabeta homodimers is consistent with the behaviour of other cystine-knot growth factors and strengthens the inclusion of the glycoprotein hormones within this superfamily. It has yet to be determined whether it is this dimeric molecular species that is responsible for growth-promoting activity of hCGbeta preparations in tumours.


Assuntos
Gonadotropina Coriônica/química , Western Blotting , Gonadotropina Coriônica/isolamento & purificação , Cromatografia em Gel , Dimerização , Eletroforese em Gel de Poliacrilamida , Humanos , Peso Molecular , Neoplasias/química , Conformação Proteica , Proteínas Recombinantes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
J Endocrinol ; 159(1): R5-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9799871

RESUMO

Trace metals and drugs have been measured in hair for a number of years but there are no published papers on the measurement of steroids in human hair. We report here the measurement of testosterone in hair samples taken from men, women and prepubertal children. This was a preliminary investigation to see whether testosterone was detectable in hair and whether concentrations between men and women, and men and prepubertal children were different in line with concentrations of testosterone in the blood. Hair was digested in sodium hydroxide and the testosterone extracted before measurement by radioimmuno- assay. There was a clear difference between testosterone concentrations found in heir collected from men (12.9-77.7 pmol/g) and those found in hair from women (<0.9-10.8 pmol/g). There was no significant difference between the concentrations found in women and children. The authenticity of the testosterone measured was confirmed with GCMS.


Assuntos
Cabelo/química , Drogas Ilícitas/análise , Testosterona/análise , Adulto , Idoso , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Couro Cabeludo
19.
Rapid Commun Mass Spectrom ; 12(14): 975-81, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9684382

RESUMO

Recognition by the legal authorities that growth hormones (GHs) may be abused to improve sporting performance and/or physique has led to the implementation of controls that make it an offence to produce, supply, possess or import and export GHs, with intent to supply, without the authority to do so. A method is described for the discriminatory analysis of human, equine, porcine and bovine GHs for forensic purposes. Peptide-mass mapping by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry following tryptic digestion gave sequence coverages of 97.4%, 93.7%, 94.2% and 90.6% for human, equine, porcine and bovine GHs respectively. The tryptic-mass maps generated were sufficient to discriminate between the four hormones analysed and thus provide unambiguous identification of each individual GH. Identification of the N-terminal peptides of recombinant equine and porcine GHs, which possess additional methionine residues, within the tryptic-mass maps may provide the basis of a test to indicate exogeneous administration rather than endogenous secretion of GH in performance dogs and horses.


Assuntos
Hormônio do Crescimento/análise , Sequência de Aminoácidos , Animais , Bovinos , Cavalos , Humanos , Hidrólise , Dados de Sequência Molecular , Mapeamento de Peptídeos , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Suínos , Tripsina
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