RESUMO
The detection of an intact ester of testosterone in plasma is leading towards unequivocal proof of the administration of exogenous testosterone. In the current study, a sensitive screening method for the detection of nine testosterone esters in human plasma was developed. By preparing oxime derivatives of intact testosterone esters, the sensitivity of the assay was increased. Furthermore, the method included liquid-liquid extraction (LLE) as sample clean-up, as well as online separation of the target analytes from the derivatization solution. The analysis was performed by liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS). The method developed herein is simple and rapid, and was validated according to World Anti-Doping Agency (WADA) guidelines.
Assuntos
Androgênios/sangue , Espectrometria de Massas em Tandem/métodos , Testosterona/sangue , Cromatografia Líquida/métodos , Dopagem Esportivo , Ésteres/sangue , Humanos , Limite de Detecção , Extração Líquido-Líquido/métodos , Oximas/sangue , Detecção do Abuso de Substâncias/métodosRESUMO
OBJECTIVE: Aromatase inhibitors are essential as endocrine treatment for hormone receptor-positive postmenopausal breast cancer patients. Menopausal symptoms are often aggravated during endocrine treatment. We investigated whether vaginal estriol is a safe therapeutic option to overcome the urogenital side-effects of aromatase inhibitors. Serum hormone levels were used as the surrogate parameter for safety. METHODS: Fasting serum hormone levels of ten postmenopausal breast cancer patients receiving aromatase inhibitors were prospectively measured by electro-chemiluminescence immunoassays and gas chromatography/mass spectrometry before and 2 weeks after daily application of 0.5 mg vaginal estriol (Ovestin® ovula), respectively. RESULTS: Two weeks of daily vaginal estriol treatment did not change serum estradiol or estriol levels. However, significant decreases in levels of serum follicle stimulating hormone (pâ=â0.01) and luteinizing hormone (pâ=â0.02) were observed. Five out of six breast cancer patients noticed an improvement in vaginal dryness and/or dyspareunia. CONCLUSIONS: The significant decline in gonadotropin levels, indicating systemic effects, has to be kept in mind when offering vaginal estriol to breast cancer patients receiving an aromatase inhibitor.
Assuntos
Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Estriol/administração & dosagem , Doenças Urogenitais Femininas , Administração Intravaginal , Inibidores da Aromatase/administração & dosagem , Cromatografia Gasosa , Monitoramento de Medicamentos , Dispareunia/induzido quimicamente , Estriol/sangue , Feminino , Doenças Urogenitais Femininas/induzido quimicamente , Doenças Urogenitais Femininas/tratamento farmacológico , Doenças Urogenitais Femininas/metabolismo , Hormônio Foliculoestimulante/sangue , Humanos , Imunoensaio , Hormônio Luteinizante/sangue , Satisfação do Paciente , Pós-Menopausa/metabolismo , Resultado do TratamentoRESUMO
A method for the quantification of five congener ephedrines in urine samples without sample preparation was developed. The analytes were trapped on a C18 precolumn and separated on a C18 BDS analytical column. Baseline separation was achieved for all analytes. The method meets the requirements of the International Olympic Committee (IOC) medical commission regarding cut-off limits for positive doping cases with ephedrines.
