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1.
Anal Chem ; 91(18): 11747-11756, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31423767

RESUMO

Carbon isotope ratio (CIR) confirmation is one of the most complex and delicate analyses in the doping control field, due to the nature of the molecules to be confirmed, normally present in urinary samples as a consequence of an endogenous production. The requirements for method validation established by the World Anti-Doping Agency (WADA) have been pushing the accredited laboratories to improve their methods. The choice of the method is always a cost benefit ratio involving a hard-working and time-consuming analysis and the guarantee of reporting of reliable results. This work presents the method fully validated by the Brazilian Doping Control Laboratory as part of the preparation for the Rio de Janeiro Summer Olympic and Paralympic Games 2016. Sample preparation encompassed solid-phase extraction, liquid-liquid extraction, enzymatic hydrolysis, acetylation, and purification by preparative high-performance liquid chromatography, and analyses were performed by gas chromatography/combustion/isotope ratio mass spectrometry. This proved to be a robust method to CIR confirmation in a big event, as demonstrated by the analysis of 179 samples during the Games 2016, from clearly negative results and adverse findings for testosterone (T) and related substances, boldenone and its metabolite, 19-norandrosterone and formestane. Two atypical findings were also reported for T and metabolites.


Assuntos
Isótopos de Carbono/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Congêneres da Testosterona/urina , Acetilação , Brasil , Cromatografia Líquida de Alta Pressão , Estranos/urina , Humanos , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Extração em Fase Sólida , Esportes , Testosterona/análogos & derivados , Testosterona/urina
2.
Femina ; 39(3)mar. 2011. tab, ilus
Artigo em Português | LILACS | ID: lil-604867

RESUMO

Os progestógenos são esteroides que podem ser sintéticos ou naturais. A progesterona é o único progestágeno natural. Os progestógenos sintéticos tentam mimetizar o efeito da progesterona, e são chamados de progestinas. Cada progestina apresenta diferentes propriedades farmacológicas, dependendo da molécula da qual foi originada, usualmente testosterona e progesterona. Pequenas mudanças estruturais nas moléculas originais levam a diferenças consideráveis na atividade de cada uma das progestinas. O objetivo deste trabalho é revisar a origem dos progestógenos, as peculiaridades de cada grupo e seu uso clínico mais comum. As informações já levantadas sobre o efeito das progestinas em patologias importantes e prevalentes, como o câncer de mama e eventos tromboembólicos, também será abordado.


Progestagens are natural or synthetic steroids, and progesterone is the only natural one. Synthetic progestagens, called progestins, were created to mimic the effects of natural progesterone. The progestins have different pharmacological properties depending on the parent molecule, usually testosterone or progesterone, from which they are derived. Very small structural changes in the original molecule may induce considerable differences in the activity of the derivative. The aim of this paper is to review the origin of each progestin, the peculiarities of each group and its most common clinical use. The current knowledge about the effect of progestins on important and prevalent diseases, such as breast cancer and thromboembolic events, will also be addressed.


Assuntos
Humanos , Masculino , Feminino , Desogestrel/farmacologia , Espironolactona/análogos & derivados , Estranos/farmacologia , Gonanos/farmacologia , Neoplasias da Mama/induzido quimicamente , Progesterona/análogos & derivados , Progesterona/farmacologia , Progestinas/farmacologia , Progestinas/síntese química , Progestinas/uso terapêutico , Tromboembolia/induzido quimicamente
8.
Rev Chil Obstet Ginecol ; 33(6): 353-62, 1968.
Artigo em Espanhol | MEDLINE | ID: mdl-4191346

RESUMO

PIP: The contractability of the Fallopian tubes is instrumental in the transport of the ovum to the uterus. Various studies have been done to determine the effect of different hormones on this property of the tubes, but they have been inconclusive. 34 patients who were scheduled for salpingectomies for reasons of birth control and who had been using steroid contraceptives for at least 3 months prior to the operation were selected for study. Half the sample had used pure progestagens (Depo-Provera or chlormadinone) and half had used a combined preparation (quinestrol + quingestanol or deladroxate). All were between 29-41 years of age with numbers of pregnancies ranging from 5 to 21. The intensity and frequency of the contractions and the general activity of the isthmus portion of the tubes were studied for 10-minute periods in 2 cm segments. Also, histological studies were done using hematoxylin eosin tincture and Van Giessen tincture, and histochemical tests were performed. The 17 cases on combined orals exhibited a significantly higher rate of activity than those on pure progestins, but were also subject to contractions of greater intensity. The histochemical studies showed a decrease in the energetic material and in the enzymatic activity related to carbohydrate metabolism in the tubes of the progestin group. The depression of motor activity and energetic metabolism was, however, neutralized by administering estrogens.^ieng


Assuntos
Acetato de Clormadinona/farmacologia , Estradiol/farmacologia , Estranos/farmacologia , Tubas Uterinas/efeitos dos fármacos , Medroxiprogesterona/farmacologia , Adulto , Tubas Uterinas/fisiologia , Feminino , Humanos , Histerossalpingografia , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Coloração e Rotulagem
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