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1.
Environ Toxicol Chem ; 43(4): 915-925, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38085110

RESUMO

Steroid hormones (SHs) have received widespread attention in recent years. However, current studies of SHs have primarily focused on estrogenic substances, with androgen-related studies being quite limited. We optimized the solid-phase extraction (SPE) pretreatment method, as well as the enzymolysis conditions of five androgens (androstenedione, boldenone, methandienone, nandrolone, and testosterone), to simultaneously determine their concentrations in the effluent from wastewater treatment plants and surface water samples. Then we evaluated the ecological risks of the five androgens in the effluent and Pearl River basin of Guangzhou (PR China) using the risk quotient method. The recovery rates of the targets were 90% to 99% in water samples when digested with ß-glucosidase for 90 min before solid-phase extraction, extracted with a Poly-Sery HLB column, and washed with 15% methanol aqueous solution and 2% ammonia. The established instrument's limit of detection was between 0.02 and 0.39 µg/L, and the limit of quantification was between 0.05 and 1.29 µg/L. Androstenedione, boldenone, methandienone, nandrolone, and testosterone were detected in all samples from the 2018 and 2022 wastewater influent and the 2018 surface water, with concentrations of 3.06 × 101 ng/L to 1.33 × 103 ng/L, 1.03-8.15 × 102 ng/L, and 0.93 × 101 ng/L to 5.50 × 102 ng/L, respectively. The ecological risks of androgens in wastewater influent and surface water were medium to high and low to medium, respectively. Moreover, the biotoxicity of androgens was predicted by the Ecological Structure Activity Relationships model, with methandienone and androstenedione having the highest and lowest acute and chronic toxicities, respectively. These results suggest that the risk of environmental androgens should not be ignored and that further research should be carried out. Environ Toxicol Chem 2024;43:915-925. © 2023 SETAC.


Assuntos
Metandrostenolona , Nandrolona , Poluentes Químicos da Água , Androgênios , Águas Residuárias , Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Androstenodiona/análise , Metandrostenolona/análise , Esteroides , Testosterona , Água/química , Nandrolona/análise , Extração em Fase Sólida , Medição de Risco , Cromatografia Líquida de Alta Pressão/métodos , Poluentes Químicos da Água/análise
2.
Horm Cancer ; 1(4): 197-204, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21533003

RESUMO

Lavage of the ductal systems of the breast provides fluid (DLF) containing hormones and products of hormone actions that may represent more accurately the composition of the breast than samples collected from blood or urine. The present study was undertaken to assess the presence of potential cancer biomarkers, their variation among individuals at high risk for breast cancer, and differences associated with menopause and tamoxifen treatment. Seventy seven tamoxifen-eligible subjects with a 5-year breast cancer risk estimate (Gail > 1.6%)(N = 53) or recently diagnosed breast cancer (N = 24) were offered tamoxifen therapy; those not accepting tamoxifen were under observation only. After six months, all subjects underwent ductal lavage (DL) in an unaffected breast. Estradiol (E2), estrone sulfate, androstenedione, dehydroepiandrosterone (DHEA), DHEA sulfate, progesterone, cathepsin D and epidermal growth factor (EGF) were measured in DLF by immunoassays. Data were expressed as the mass of analyte per mg of protein in DLF and normalized by natural log transformation. With the exception of DHEA, none of the analytes measured were significantly lower in postmenopausal women than in premenopausal women. The mean log(e) concentration difference in estradiol was 10.9%. Tamoxifen treatment for 6 months did not result in a significantly greater concentration of E2 or in any of the other analytes in DLF of pre- or postmenopausal women. The between-duct variance of the concentration of free steroids within the same breast averaged 51% less than that between subjects, and was similar to that of non-diffusible proteins. The maintenance of estradiol concentrations in the breast after menopause demonstrates the importance of local biosynthesis. The fact that DLF E2 does not reflect the high serum concentrations of E2 during tamoxifen treatment indicates that breast concentrations of estradiol may be under feedback control. Unlike studies of low risk populations, progesterone concentrations were not significantly less in postmenopausal than in premenopausal women. The similarity in variance of free steroids and protein analytes between ducts of a breast indicates little transfer of steroids between lobules.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Mama/metabolismo , Adulto , Idoso , Análise de Variância , Androstenodiona/análise , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Catepsina D/análise , Desidroepiandrosterona/análise , Fator de Crescimento Epidérmico/análise , Estradiol/análise , Estrona/análise , Feminino , Humanos , Imunoensaio , Pessoa de Meia-Idade , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Progesterona/análise , Tamoxifeno/uso terapêutico , Irrigação Terapêutica
3.
J Chromatogr Sci ; 45(8): 519-23, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18019562

RESUMO

This paper describes the development of a normal-phase liquid chromatograph-UV-diode array detection-positive ion atmospheric pressure chemical ionization-mass spectrometry method for the simultaneous identification and quantitation of cholesterol, androst-4-ene-3,17-dione (AD), and androsta-1,4-diene-3,17-dione (ADD) in fermentation broths. The compounds detected under positive ion atmospheric pressure chemical ionization on a mass spectrometer by selected ion monitoring are separated by normal-phase high-performance liquid chromatography. [M+H]+ ions are taken into consideration for quantitation of AD and ADD, and [M-H2O+H]+ ions are considered for quantitation of cholesterol. The compounds are analyzed on a Si60 silica (5 microm, 125 x 4-mm i.d.) Merck column using a 2:3 isocratic mixture of isopropyl alcohol and hexane. The calibration curves resulting from the reference compounds in the concentration range of 100-5000 pg on column exhibit a good linear correlation (r2 > or = 0.996). The method is validated by analyzing six replicates of broth samples fortified with three compounds, namely, cholesterol, AD, and ADD, at 0.050 and 0.5 microg/g levels. The mean recoveries for the fortifications range from 90% to 98% with relative standard deviations in the range of 3.36% to 9.78%. The method is developed to study the qualitative as well as quantitative conversion of cholesterol to AD and ADD by a microorganism identified as Nocardia sp. These studies helped the investigation of the reaction kinetics, which showed that the molar biotransformation of cholesterol into AD and ADD was 21%, even when the reaction was prolonged for 96 h.


Assuntos
Androstadienos/análise , Androstenodiona/análise , Colesterol/análise , Espectrometria de Massas/métodos , Pressão Atmosférica , Padrões de Referência , Espectrofotometria Ultravioleta
4.
J Pharm Biomed Anal ; 39(3-4): 718-23, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15905063

RESUMO

A method of increasing the sensitivity of 3beta-hydroxy-5-ene (Delta5)-steroids in liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) based on the structural conversion by cholesterol oxidase (ChO) was demonstrated. The Delta5-steroids were rapidly converted to their 3-oxo-4-ene (Delta4)-forms by the treatment with ChO and the obtained Delta4-forms provided 3-14-fold higher sensitivity compared to intact steroids in the positive-APCI-MS. This enzymic conversion method was also applied to the sulfated conjugates of Delta5-steroids after solvolysis. The method enabled the detection of trace levels of dehydroepiandrosterone and androstenediol 3-sulfate in human serum, which could not be detected by the usual LC-MS.


Assuntos
Androstenodiona/química , Colesterol Oxidase/análise , Cromatografia Líquida/métodos , Desidroepiandrosterona/química , Espectrometria de Massas/métodos , Pregnenolona/química , Progesterona/química , Esteroides/química , Sulfatos/química , Testosterona/química , Androstenodiona/análise , Química Farmacêutica/métodos , Colesterol Oxidase/química , Desidroepiandrosterona/análise , Indústria Farmacêutica/métodos , Humanos , Pregnenolona/análise , Progesterona/análise , Sensibilidade e Especificidade , Esteroides/análise , Testosterona/análise , Fatores de Tempo
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