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1.
BMC Cancer ; 11: 342, 2011 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21824401

RESUMO

BACKGROUND: To evaluate the metabolic changes in urinary steroids in pre- and post-menopausal women and men with papillary thyroid carcinoma (PTC). METHODS: Quantitative steroid profiling combined with gas chromatography-mass spectrometry was used to measure the urinary concentrations of 84 steroids in both pre- (n = 21, age: 36.95 ± 7.19 yr) and post-menopausal female (n = 19, age: 52.79 ± 7.66 yr), and male (n = 16, age: 41.88 ± 8.48 yr) patients with PTC. After comparing the quantitative data of the patients with their corresponding controls (pre-menopause women: n = 24, age: 33.21 ± 10.48 yr, post-menopause women: n = 16, age: 49.67 ± 8.94 yr, male: n = 20, age: 42.75 ± 4.22 yr), the levels of steroids in the patients were normalized to the mean concentration of the controls to exclude gender and menopausal variations. RESULTS: Many urinary steroids were up-regulated in all PTC patients compared to the controls. Among them, the levels of three active androgens, androstenedione, androstenediol and 16α-hydroxy DHEA, were significantly higher in the pre-menopausal women and men with PTC. The corticoid levels were increased slightly in the PTC men, while progestins were not altered in the post-menopausal PTC women. Estrogens were up-regulated in all PTC patients but 2-hydroxyestrone and 2-hydroxy-17ß-estradiol were remarkably changed in both pre-menopausal women and men with PTC. For both menopausal and gender differences, the 2-hydroxylation, 4-hydroxylation, 2-methoxylation, and 4-methoxylation of estrogens and 16α-hydroxylation of DHEA were differentiated between pre- and post-menopausal PTC women (P < 0.001). In particular, the metabolic ratio of 2-hydroxyestrone to 2-hydroxy-17ß-estradiol, which could reveal the enzyme activity of 17ß-hydroxysteroid dehydrogenase, showed gender differences in PTC patients (P < 1 × 10-7). CONCLUSIONS: These results are expected be helpful for better understanding the pathogenic differences in PTC according to gender and menopausal conditions.


Assuntos
Carcinoma Papilar/urina , Pós-Menopausa/urina , Pré-Menopausa/urina , Esteroides/urina , Neoplasias da Glândula Tireoide/urina , Adulto , Androstenodiol/metabolismo , Androstenodiol/urina , Androstenodiona/metabolismo , Androstenodiona/urina , Carcinoma Papilar/metabolismo , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/metabolismo , Desidroepiandrosterona/urina , Estradiol/análogos & derivados , Estradiol/metabolismo , Estradiol/urina , Estrogênios/metabolismo , Estrogênios/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxiestronas/metabolismo , Hidroxiestronas/urina , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Fatores Sexuais , Esteroides/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
2.
J Chromatogr A ; 1093(1-2): 69-80, 2005 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-16233872

RESUMO

The use of anabolic agents in food producing animals is prohibited within the EU since 1988 (96/22/EC directive). The control of the illegal use of natural steroid hormones in cattle is still an exciting analytical challenge as far as no definitive method and non-ambiguous analytical criteria are available. The ability of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to demonstrate the administration of 17beta-estradiol to bovine has been investigated in this paper. By comparison of 13C/12C isotopic ratio of main urinary estradiol metabolite, i.e. 17alpha-estradiol, with two endogenous reference compounds (ERCs), i.e. dehydroepiandrosterone (DHEA) and 5-androstene-3beta,17alpha-diol, the differentiation of estradiol metabolite origin, either endogenous or exogenous, has been proved to be achievable. After treatment, the delta(13)C(VPDB)-values of 17alpha-estradiol reached -27 per thousand to -29 per thousand, whereas delta13CVPDB-values of DHEA remained between -13 per thousand and -20 per thousand depending on the diet, maize and grass, respectively. A significant difference of delta13CVPDB between ERCs and 17alpha-estradiol was measurable over a period of 2 weeks after estradiol ester administration to the animal.


Assuntos
Isótopos de Carbono/análise , Estradiol/administração & dosagem , Androstenodiol/análogos & derivados , Androstenodiol/urina , Animais , Bovinos , Desidroepiandrosterona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Padrões de Referência
3.
Artigo em Inglês | MEDLINE | ID: mdl-11824814

RESUMO

The dietary supplements 19-norandrostenedione and 19-norandrostenediol are potential metabolic precursors of nandrolone. They are considered by law in the United States as prohormones without proven therapeutic, curative or diagnostic properties, and therefore available as over-the-counter drugs. Oral dosages of 0.1-1 mg/kg body weight were readily absorbed in the equine intestinal tract and thereby led to urinary excretion of drastically increased 5alpha-estrane-3beta,17alpha-diol conjugates, which are known to be final metabolites of nandrolone. The actual rules for detection of illicit nandrolone administration to the horse have been found applicable for the detection of surreptitious oral 19-norandrostenedione and 19-norandrostenediol supplementation. Secondary markers of these administrations were high-level excretions of conjugated nandrolone, epinandrolone, 19-noretiocholanolone and 19-norepiandrosterone. No significant increase of circulating, biologically active nandrolone could be firmly evidenced, and it is therefore unclear to what extent continuous long-term administrations may have anabolic action.


Assuntos
Androstenodiol/metabolismo , Androstenodiona/metabolismo , Suplementos Nutricionais , Dopagem Esportivo , Androstenodiol/sangue , Androstenodiol/urina , Androstenodiona/análogos & derivados , Androstenodiona/sangue , Androstenodiona/urina , Animais , Cavalos , Humanos
4.
Prenat Diagn ; 18(8): 789-800, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9742566

RESUMO

A method for determining whether a pregnant woman with an extremely low serum oestriol (ELSE) measurement of mid-trimester is carrying a fetus with steroid sulphatase deficiency or another more serious disorder is described. We undertook GC/MS analysis of steroids in random maternal urine samples and quantified oestriol, oestriol precursors (dehydroepiandrosterone (DHEA), 5-androstene-3 beta, 17 beta-diol, 16 alpha-hydroxy-dehydroepiandrosterone and 5-androstene-3 beta, 16 alpha, 17 beta-triol), pregnanediol, and five other steroids largely unaffected by pregnancy (androsterone, etiocholanolone, tetrahydrocortisol, 5 alpha-tetrahydrocortisol and tetrahydrocortisone). Thirty-two samples collected from seven normal pregnant women between the 7th and 27th week of pregnancy and 22 from individuals with ELSE were analysed. Diagnostic ratios of excreted products were developed. These included ratios of oestriol and oestriol precursors to the cumulative value for the five non-pregnancy-related steroids and ratios of oestriol and oestriol precursors to pregnanediol and to each other. Our data demonstrated high 3 beta-hydroxy-5-ene steroid excretion in all ELSE patients together with low urinary oestriol excretion, a situation only consistent with deficiency of steroid sulphatase. The normal individuals had high oestriol and low excretion of oestriol precursors. No patient in our series showed the low oestriol levels and low oestriol precursor values that would indicate a fetal adrenal abnormality as the underlying defect.


Assuntos
Arilsulfatases/deficiência , Estriol/biossíntese , Diagnóstico Pré-Natal , Precursores de Proteínas/urina , Esteroides/urina , Androstenodiol/urina , Androstenóis/urina , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/urina , Estriol/sangue , Estriol/urina , Feminino , Feto/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Idade Gestacional , Humanos , Gravidez , Segundo Trimestre da Gravidez , Pregnanodiol/urina , Esteril-Sulfatase
5.
Steroids ; 62(10): 665-73, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9381514

RESUMO

The basis of a potential method for confirming intake of four natural androgens (testosterone, epitestosterone, dihydrotestosterone, and dehydroepiandrosterone is presented. The method relies on isolating from urine a steroid fraction containing androstenediol and androstanediol metabolites of these natural steroids and analyzing their 13C content by gas chromatography, combustion, isotope ratio mass spectrometry. The steroids were recovered from urine by conjugate hydrolysis with a Helix pomatia preparation (sulfatase and beta-glucuronidase), Girard T reagent separation to obtain a nonketonic fraction, and Sephadex LH-20 chromatography for purification. Metabolites appropriate for all of the natural steroids could be separated (as diacetates) by gas chromatography on a DB-17 capillary column viz.: 5 alpha (and beta)-androstane-3 alpha,17 alpha-diol (epitestosterone as precursor); 5 alpha (and beta)-androstane-3 alpha,17 beta-diol (testosterone as precursor); 5-androstene-3 beta,17 beta-diol (dehydroepiandrosterone precursor); and 5 alpha-androstane-3 alpha,17 beta- (and 17 alpha-) diol (dihydrotestosterone precursor). Measurement of the 13C content of the specific analytes after ingestion of the androgen precursors demonstrated a lowering of delta 13C/1000 value compared to normal values. Typically, in the male individual studied, delta 13C/1000 values for all components were -26 to -27 before drug administration and -29 to -30 at 6 h after, the latter values reflecting those obtaining for commercial synthetic steroid compared to in vivo synthesized steroid. While generally the metabolism of the steroids was as expected, this was not the case for 5 alpha-dihydrotestosterone. A major metabolite was 5 alpha-androstane-3 alpha,17 alpha-diol, which had presumably been formed by 17 beta/17 alpha isomerization, a process previously known for unnatural anabolics but not for natural hormones. The isolation, purification, and isotope ratio mass spectrometry techniques described may form the basis of a general method for confirming natural steroid misuse by sports participants.


Assuntos
Androstano-3,17-diol/urina , Androstenodiol/urina , Desidroepiandrosterona/administração & dosagem , Di-Hidrotestosterona/administração & dosagem , Dopagem Esportivo , Epitestosterona/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Detecção do Abuso de Substâncias/métodos
6.
Eur J Endocrinol ; 130(1): 53-9, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8124479

RESUMO

In this cross-sectional study on 140 subjects, several testosterone and epitestosterone metabolites have been analyzed by gas chromatography-mass spectrometry associated with stable isotope dilution, a technique requested for doping analysis in general, and detection of exogenous testosterone supply in particular. Urinary excretions of luteinizing hormone, testosterone and epitestosterone glucuronides and sulfates, as well as glucuronides of 5-androstene-3 beta, 17 alpha-diol, 5 alpha- and 5 beta-androstane-3 alpha, 17 alpha-diol and the corresponding 17 beta-isomers, present similar patterns of increase throughout pubertal development, from stage 1 up to stage 5. Excretion levels are significantly different in general between stages 1, 2, 3 and 4, the highest percentage increase being observed between stages 3 and 4. None of the ratios of testosterone to epitestosterone glucuronides are beyond the threshold value of 6, where testosterone abuse by athletes is suspected. No particular pubertal stage exceeded this critical value with a probability higher than p = 0.006, a value that was determined on the whole population. This is consistent with the non-significant differences between correlation slopes of regression curves, relating either testosterone or epitestosterone glucuronide to chronological age. The ratio of testosterone glucuronide to luteinizing hormone increases significantly throughout puberty and this might be a limitation to the widespread use of this ratio for the detection of testosterone misuse.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Epitestosterona/metabolismo , Exercício Físico/fisiologia , Puberdade/metabolismo , Esportes , Testosterona/metabolismo , Adolescente , Adulto , Androstano-3,17-diol/urina , Androstenodiol/urina , Estudos Transversais , Dopagem Esportivo , Epitestosterona/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hormônio Luteinizante/urina , Masculino , Valores de Referência , Análise de Regressão , Testosterona/análogos & derivados , Testosterona/urina
7.
Clin Endocrinol (Oxf) ; 39(4): 469-74, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8287574

RESUMO

OBJECTIVES: We developed an assay for delta-5-androstenediol (adiol) and delta-5-androstenediol-3-sulphate (adiol-3S) in serum and adiol and total adiol sulphate (adiol-S) in urine. DESIGN: An analytical procedure using HPLC and gas chromatography-mass spectrometry was devised and tested for its reliability. MEASUREMENTS: After addition of deuterated androstenediol as internal standard, serum and urine samples were extracted. Steroid sulphates were hydrolysed. The extracts and hydrolysates were purified on HPLC, adiol was derivatized using heptafluorobutyric anhydride and finally quantified by gas chromatography-mass spectrometry. RESULTS: The assay is accurate and reproducible. The coefficient of variation (CV) for the determination of adiol in serum samples is 4% (intra-assay) and 9% (interassay) and for urine samples 3 and 8% respectively. The intra-assay CV for the adiol-3S analyses is 5% for serum and 2% for urine samples while the interassay CV values for adiol-3S are 10% for serum and 7% for urine samples. The recovery of adiol and adiol-3S from serum and urine samples is 97%. CONCLUSIONS: The developed assay meets the analytical demands needed for clinical applications.


Assuntos
Androstenodiol/análise , Androstenodiol/análogos & derivados , Androstenodiol/sangue , Androstenodiol/urina , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Reprodutibilidade dos Testes
8.
Clin Endocrinol (Oxf) ; 39(4): 475-82, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8287575

RESUMO

OBJECTIVES: We evaluated the role of delta-5-androstenediol (adiol) and its sulphates in health and endocrine diseases. DESIGN: Serum and urine samples from healthy adult men and pre and post-menopausal women were analysed by gas chromatography-mass spectrometry to establish reference values. In patients who were either evaluated or treated for endocrine diseases, sequential serum samples were collected and analysed. PATIENTS: Reference values were obtained from 24 healthy male, 23 premenopausal and 30 post-menopausal female volunteers. Adiol and delta-5-androstenediol-3-sulphate (adiol-3S) concentrations were determined in combination with other relevant steroids in patients with either pituitary (n = 5), adrenal (n = 2) or gonadal dysfunction (n = 1), or testicular carcinoma (n = 19). MEASUREMENTS: After addition of deuterated adiol as internal standard, serum and urine samples were extracted. Steroid sulphates were hydrolysed. The extracts and hydrolysates were purified on HPLC, adiol was derivatized and finally quantified by gas chromatography-mass spectrometry. RESULTS: The calculated reference ranges for adiol and adiol-3S concentrations in serum are respectively: in men 1.78-7.24 and 123-579 nmol/l, in premenopausal women 0.65-6.93 and 21.2-298 nmol/l and in post-menopausal women 0.29-2.90 and 6.1-184 nmol/l. Urinary values varied considerably. In the population with endocrine abnormalities serum adiol and adiol-3S concentrations were compared with other relevant steroids. CONCLUSIONS: The wide concentration range of adiol and adiol-3S in urine makes analysis of these steroids in urine of little clinical value. Serum concentrations of adiol and adiol-3S are higher in men than in women. Premenopausal values are higher than post-menopausal. Adiol and adiol-3S in serum are significantly correlated in pre and post-menopausal women, r = 0.51 and r = 0.69 respectively, but not in men. In endocrine patients the serum concentrations of adiol show an ACTH or LH dependency in women; adiol correlates with cortisol, dehydroepiandrosterone or androstenedione and, in males, additionally with testosterone. However, in several situations adiol correlates with none of these steroids. Although adiol secretion can be stimulated by ACTH and LH, the level of serum adiol is also determined by other factors. Finally, in adrenal carcinoma serum adiol and adiol-3S may be used as tumour markers.


Assuntos
Androstenodiol/análise , Doenças do Sistema Endócrino/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstenodiol/análogos & derivados , Androstenodiol/sangue , Androstenodiol/urina , Biomarcadores/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Valores de Referência , Fatores Sexuais
9.
J Steroid Biochem ; 29(1): 105-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3347043

RESUMO

To study in vivo the conversion of testosterone (T) into its metabolites, dihydro-testosterone (DHT) and 5 alpha-androstane-3 alpha, 17 beta diol (3 alpha-Diol) the urinary excretion rates of these steroids were determined by mass spectrometry in 6 healthy men during/after the i.v. infusion (t = 4 h) of 20 mg [13C]testosterone. In addition, plasma concentrations of T, DHT and 3 alpha-Diol were determined by radioimmunoassay. During steady state conditions at the end of the 4-h infusion of [13C]T the increase in the plasma concentrations of T from, basal, 405 +/- 140 ng/dl to 4205 +/- 804 ng/dl was paralleled by an increase in the plasma concentrations of DHT to 106.4 +/- 62.5 ng/dl) (basal: 30.8 +/- 21.8 ng/dl), and of 3 alpha-Diol to 32.2 +/- 12.5 ng/dl (basal: 12.5 +/- 13.9 ng/dl). Plasma concentrations of T, DHT and 3 alpha-Diol then returned to basal concentrations within 24 hours. Using mass-spectrometry we found a cumulative renal excretion of 13C-labelled T of 15.6 +/- 9.6 micrograms/24 h, equivalent to 0.08 +/- 0.05% of the infused amount (20 mg) of [13C]T. Whereas urinary excretion of [13C]DHT was below the level of detection by mass-spectrometry the cumulative excretion of [13C]3 alpha-Diol was 67.7 +/- 19.9 micrograms/24 hours which is equivalent to 0.3 +/- 0.1% of the infused dose of 13C-labelled testosterone. These data suggest that the determination of urinary 3 alpha-Diol by mass-spectrometry during/after the infusion of stable-labelled testosterone represents an alternative to the use of radioactive label for turnover studies.


Assuntos
Androstenodiol/urina , Androstenodióis/urina , Testosterona/administração & dosagem , Adulto , Androstenodiol/sangue , Isótopos de Carbono , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Infusões Intravenosas , Masculino , Radioimunoensaio , Testosterona/sangue , Testosterona/urina
10.
J Steroid Biochem ; 24(2): 577-80, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2939298

RESUMO

Trilostan (240, 360 and 480 mg/day administered p.o. to healthy men) induced an increase (P less than 0.05) in the urinary excretion rates of DHEA, androstenediol and pregnenolone but failed to influence the excretion rates of cortisol, aldosterone, and of the four glucocorticoid metabolites, THF, allo-THF, THE and allo-THE. A rise in plasma renin concentrations was seen in the initial phase of the trial. Administration of dexamethasone in addition to trilostan suppressed plasma and urinary concentrations of cortisol and the excretion rates of all estimated steroid metabolites but did not modify the relative abundance in the excretion rates of DHEA, androstenediol and pregnenolone. These results confirm that trilostan interferes with the activity of 3 beta-hydroxysteroid dehydrogenase in man. However, under physiological conditions production of cortisol and aldosterone is kept at a constant level, most likely by compensatory stimulation of the secretion of ACTH and renin.


Assuntos
3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Di-Hidrotestosterona/análogos & derivados , Esteroides/metabolismo , Adulto , Aldosterona/metabolismo , Androstenodiol/urina , Cromatografia Gasosa , Desidroepiandrosterona/urina , Dexametasona/farmacologia , Di-Hidrotestosterona/farmacologia , Glucocorticoides/metabolismo , Humanos , Hidrocortisona/metabolismo , Masculino , Pregnenolona/urina , Renina/sangue
11.
Ann Endocrinol (Paris) ; 45(2): 143-8, 1984.
Artigo em Francês | MEDLINE | ID: mdl-6239589

RESUMO

The sulphoconjugates of delta 5-C19O2 steroids were determined in 32 women with idiopathic hirsutism (IH). The plasma and urinary levels of 5-androsten-3 beta, 17 beta-diol (delta 5, 3 beta-diol) were 82 +/- 24 ng/ml and 169 +/- 170 micrograms/24 h respectively for the monosulphate ester and 193 +/- 101 ng/ml and 180 +/- 108 micrograms/24 h for the disulphate ester. These levels are statistically higher (p less than 0,001) as compared with the levels observed in women without IH (30 +/- 20 ng/ml and 23 +/- 13 micrograms/24 h for the monosulphate, 78 +/- 40 ng/ml and 48,0 +/- 23,7 micrograms/24 h for the disulphate). There is a correlation between the urinary levels of the monosulphate of delta 5, 3 beta-diol (y) and of the dehydroepiandrosterone sulphate (S-DHA) (x) : y (microgram/24 h) = 0,124x + 16,8; r = 0,93 (p less than 0,01) and n = 32. The plasma levels of S-DHA ranged form 1,250 ng/ml to 7,000 ng/ml in the abnormal population and from 1,000 ng/ml to 2,400 ng/ml in the normal population. A concomitant determination of plasma free androgens showed that 60 % of the dehydroepiandrosterone values were above the upper limits of normal values. Conversely, the testosterone and androstenedione levels were only higher in 20 % and 27 % of cases respectively. These results suggest that the possible importance of the sulphoconjugates of delta 5-C19O2 steroids in the IH pathogeny should not be overlooked.


Assuntos
Androstenodiol/metabolismo , Androstenodióis/metabolismo , Hirsutismo/metabolismo , Adulto , Androstenodiol/análogos & derivados , Androstenodiol/sangue , Androstenodiol/urina , Androstenodiona/sangue , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Desidroepiandrosterona/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Radioimunoensaio , Testosterona/sangue
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