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1.
Environ Sci Pollut Res Int ; 31(20): 29460-29471, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38578593

RESUMO

This work proposes the use of multi-criteria decision analysis (MCDA) to select a more environmentally friendly analytical procedure. TOPSIS, which stands for Technique for Order of Preference by Similarity to Ideal Solution, is an example of a MCDA method that may be used to rank or select best alternative based on various criteria. Thirteen analytical procedures were used in this study as TOPSIS input choices for mifepristone determination in water samples. The input data, which consisted of these choices, was described using assessment criteria based on 12 principles of green analytical chemistry (GAC). Based on the objective mean weighting (MW), the weights for each criterion were assigned equally. The most preferred analytical method according to the ranking was solid phase extraction with micellar electrokinetic chromatography (SPE-MEKC), while solid phase extraction combined with ultra-high performance liquid chromatography tandem mass spectrometry (SPE-UHPLC-MS/MS) was ranked last. TOPSIS ranking results were also compared to the green metrics NEMI, Eco-Scale, GAPI, AGREE, and AGREEprep that were used to assess the greenness of thirteen analytical methods for mifepristone determination. The results demonstrated that only the AGREE metric tool correlated with TOPSIS; however, there was no correlation with other metric tools. The analysis results suggest that TOPSIS is a very useful tool for ranking or selecting the analytical procedure in terms of its greenness and that it can be easily integrated with other green metrics tools for method greenness assessment.


Assuntos
Mifepristona , Poluentes Químicos da Água , Mifepristona/análise , Poluentes Químicos da Água/análise , Técnicas de Apoio para a Decisão , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
2.
BMC Pharmacol Toxicol ; 23(1): 55, 2022 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-35869506

RESUMO

BACKGROUND: As a progesterone receptor antagonist, mifepristone combined with misoprostol is widely used to terminate early pregnancy in clinical practice. It has also been reported that mifepristone may cause cell death in decidual cells and result in hemorrhage of the decidua and insufficient blood supply. However, little is known about the histological effects of mifepristone on human decidua and chorion. METHODS: Histological and subcellular structural changes of decidua and chorionic villi from women taking mifepristone at early pregnancy times were examined by Hematoxylin and eosin (H&E) staining and transmission Electron microscope. The expression of apoptosis-related proteins Bax/Bcl-2 was examined by immunohistochemistry. RESULTS: After 48 h of mifepristone administration, the decidua tissue and chorionic villus structures were altered in women within 39-49 days of gestation and displayed varying degrees of degeneration and necrosis-like features. Apoptotic events were observed in the decidua and chorionic villi of early pregnancy, and mifepristone treatment significantly increases the number of apoptotic cells. The increased apoptotic events were concomitant with the increased expression of Bax and decreased expression of Bcl-2. CONCLUSION: This study provides evidence that mifepristone induces histological and subcellular changes in decidua and chorionic villi. Mifepristone modulates the relative ratio of Bax/Bcl-2 and the increased apoptosis contributes to the pregnancy termination at early stage of pregnancy.


Assuntos
Mifepristona , Misoprostol , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Vilosidades Coriônicas/química , Vilosidades Coriônicas/metabolismo , Vilosidades Coriônicas/patologia , Decídua/química , Decídua/metabolismo , Feminino , Humanos , Mifepristona/análise , Mifepristona/metabolismo , Mifepristona/farmacologia , Misoprostol/análise , Misoprostol/metabolismo , Misoprostol/farmacologia , Gravidez
3.
Aquat Toxicol ; 179: 8-17, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27541482

RESUMO

Endocrine active compounds (EACs) remain an important group of chemicals that require additional evaluation to determine their environmental impacts. While estrogens and androgens were previously demonstrated to impact organisms during environmental exposures, progestagens have recently been shown to have strong impacts on aquatic organisms. To gain an understanding of the impacts of these types of chemicals on aquatic species, experiments evaluating the mechanisms of action of progestagen exposure were conducted with the Eastern Mosquitofish (Gambusia holbrooki). The objective of this study was to conduct hepatic microarray analysis of male and female G. holbrooki exposed to progestins and anti-progestagens. In addition, we evaluated the ability of levonorgestrel, a synthetic progesterone (progestin), to induce anal fin elongation and to determine how anal fin growth is modulated during co-exposures with progesterone and androgen receptor antagonists. Gene expression analyses were conducted on male and female G. holbrooki exposed for 48h to the agonist levonorgestrel, the antagonist mifepristone, or a mixture of the two chemicals. Microarray analysis revealed that mifepristone does not act as an anti-progestagen in G. holbrooki in liver tissues, and that levonorgestrel elicits strong effects on the processes of embryo development and lipid transport. Levonorgestrel was also demonstrated to induce male secondary sexual characteristic formation in females, and co-exposure of either an androgen or levonorgestrel in the presence of the anti-androgen flutamide prevented anal fin elongation. These results provide indications as to the potential impacts of progestins, including non-target effects such as secondary sexual characteristic formation, and demonstrate the importance of this class of chemicals on aquatic organisms.


Assuntos
Antagonistas de Receptores de Andrógenos/toxicidade , Progestinas/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Antagonistas de Androgênios/toxicidade , Nadadeiras de Animais/efeitos dos fármacos , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Ciprinodontiformes/genética , Ciprinodontiformes/metabolismo , Ciprinodontiformes/fisiologia , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Hibridização In Situ , Levanogestrel/análise , Levanogestrel/isolamento & purificação , Masculino , Análise em Microsséries , Mifepristona/análise , Mifepristona/isolamento & purificação , Extração em Fase Sólida , Poluentes Químicos da Água/química
4.
Bioconjug Chem ; 24(5): 766-71, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23600997

RESUMO

We employed molecular modeling to design and then synthesize fluorescent ligands for the human progesterone receptor. Boron dipyrromethene (BODIPY) or tetramethylrhodamine were conjugated to the progesterone receptor antagonist RU486 (Mifepristone) through an extended hydrophilic linker. The fluorescent ligands demonstrated comparable bioactivity to the parent antagonist in live cells and triggered nuclear translocation of the receptor in a specific manner. The BODIPY labeled ligand was applied to investigate the dependency of progesterone receptor nuclear translocation on partner proteins and to show that functional heat shock protein 90 but not immunophilin FKBP52 activity is essential. A tissue distribution study indicated that the fluorescent ligand preferentially accumulates in tissues that express high levels of the receptor in vivo. The design and properties of the BODIPY-labeled RU486 make it a potential candidate for in vivo imaging of PR by positron emission tomography through incorporation of (18)F into the BODIPY core.


Assuntos
Compostos de Boro/análise , Corantes Fluorescentes/análise , Antagonistas de Hormônios/análise , Mifepristona/análise , Receptores de Progesterona/antagonistas & inibidores , Receptores de Progesterona/metabolismo , Compostos de Boro/metabolismo , Mama/citologia , Mama/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Corantes Fluorescentes/metabolismo , Antagonistas de Hormônios/metabolismo , Humanos , Mifepristona/metabolismo , Modelos Moleculares , Imagem Óptica , Receptores de Progesterona/análise
5.
Acta Obstet Gynecol Scand ; 89(5): 618-22, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20367522

RESUMO

OBJECTIVE: Medical abortion using mifepristone followed by misoprostol is increasingly used for termination of an unwanted pregnancy. Consequently, an increasing number of women undergo medical abortion while still breastfeeding from a previous pregnancy. But there are no data on mifepristone use during lactation. We studied the levels of mifepristone in breast milk collected from women undergoing medical abortion. DESIGN AND SAMPLES: Samples of milk were collected from 12 women during the first 7 days after intake of either 200 mg (n = 2) or 600 mg (n = 10) of mifepristone. In addition, serum samples were collected on day 3 (n = 4). Main outcome measures. The levels of mifepristone, quantified using radioimmunoassay. RESULTS: The milk concentrations of mifepristone were highest in the first samples collected during the first 12 hours following drug intake, and ranged from undetectable (< 0.013 micromol/l) to 0.913 micromol/l. Thereafter, declining concentrations of mifepristone were detected up to 7 days. The lowest levels of mifepristone in milk were measured following ingestion of the 200 mg dose. The milk:serum ratio of mifepristone ranged from < 0.013:1 to 0.042:1 on day 3 (n = 4). The calculated relative infant dose (RID) was 1.5% at its highest. CONCLUSIONS: The levels of mifepristone in milk are low, especially when using the 200 mg dose. Breastfeeding can be safely continued in an uninterrupted manner during medical abortion of this kind.


Assuntos
Abortivos Esteroides/análise , Aborto Induzido , Mifepristona/administração & dosagem , Mifepristona/análise , Leite Humano/química , Abortivos Esteroides/administração & dosagem , Abortivos Esteroides/farmacocinética , Aborto Induzido/métodos , Administração Oral , Adulto , Aleitamento Materno , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactação/efeitos dos fármacos , Mifepristona/farmacocinética , Gravidez , Gravidez não Desejada/efeitos dos fármacos , Estudos Prospectivos , Radioimunoensaio , Medição de Risco , Gestão da Segurança , Fatores de Tempo , Resultado do Tratamento
6.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(7-8): 719-23, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20149766

RESUMO

A rapid, specific and sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed and validated for determination of cymipristone in human plasma. Mifepristone was used as the internal standard (IS). Plasma samples were deproteinized using methanol. The compounds were separated on a ZORBAX SB C(18) column (50 mm x 2.1 mm i.d., dp 1.8 microm) with gradient elution at a flow-rate of 0.3 ml/min. The mobile phase consisted of 10 mM ammonium acetate and acetonitrile. The detection was performed on a triple-quadruple tandem mass spectrometer by selective reaction monitoring (SRM) mode via electrospray ionization. Target ions were monitored at [M+H](+)m/z 498-->416 and 430-->372 in positive electrospray ionization (ESI) mode for cymipristone and IS, respectively. Linearity was established for the range of concentrations 0.5-100 ng/ml with a coefficient correlation (r) of 0.9996. The lower limit of quantification (LLOQ) was identifiable and reproducible at 0.5 ng/ml. The validated method was successfully applied to study the pharmacokinetics of cymipristone in healthy Chinese female subjects.


Assuntos
Cromatografia Líquida/métodos , Estrenos/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Estabilidade de Medicamentos , Estrenos/química , Estrenos/farmacocinética , Feminino , Humanos , Modelos Lineares , Mifepristona/análise , Mifepristona/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Mol Pharmacol ; 73(3): 845-54, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18042733

RESUMO

Breast cancer resistance protein (BCRP) plays a significant role in drug disposition and in conferring multidrug resistance in cancer cells. Previous studies have shown that steroid hormones such as 17beta-estradiol and progesterone can affect BCRP expression in cancer cells. In this study, we investigated the molecular mechanism by which BCRP expression in human placental choriocarcinoma BeWo cells is regulated by progesterone. Transfection of the progesterone receptor (PR) isoforms PRA and PRB resulted in a similarly increased expression of PRA and PRB, respectively. However, progesterone significantly increased BCRP expression and activity only in PRB-transfected cells. This stimulatory effect of progesterone was abrogated by the PR antagonist mifepristone (RU-486). Consistently, transcriptional activity of the BCRP promoter was induced 2- to 6-fold by 10(-8) to 10(-5) M progesterone in PRB-transfected cells. Progesterone had little effect on BCRP expression and activity and transcriptional activity of the BCRP promoter in PRA-transfected cells; however, cotransfection of PRA and PRB significantly decreased the progesterone-response compared with that in cells transfected with only PRB. Mutations in a novel progesterone response element (PRE) identified between -243 to -115 bp of the BCRP promoter region significantly attenuated the progesterone-response in PRB-transfected cells, and deletion of the PRE nearly completely abrogated the progesterone effect. Specific binding of both PRA and PRB to the BCRP promoter through the identified PRE was confirmed using the electrophoretic mobility shift assay. Collectively, progesterone induces BCRP expression in BeWo cells via PRB but not PRA. PRA represses the PRB activity. Thus, PRA and PRB differentially regulate BCRP expression in BeWo cells.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Receptores de Progesterona/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Coriocarcinoma/patologia , Relação Dose-Resposta a Droga , Feminino , Deleção de Genes , Humanos , Luciferases/metabolismo , Mifepristona/análise , Mifepristona/farmacologia , Mutação , Proteínas de Neoplasias/metabolismo , Placenta/efeitos dos fármacos , Placenta/metabolismo , Placenta/patologia , Gravidez , Progesterona/análise , Progesterona/farmacologia , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Progesterona/antagonistas & inibidores , Receptores de Progesterona/metabolismo , Elementos de Resposta/genética , Estatística como Assunto , Transcrição Gênica , Transfecção , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia
8.
Fresenius J Anal Chem ; 368(8): 832-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11227571

RESUMO

A new strategy for the preparation of a DNA-modified carbon paste electrode is developed. It is found that the anodic response of mifepristone is greatly enhanced at the dsDNA-modified carbon paste electrode comparing with that obtained at the bare electrode, while the response at a ssDNA-modified electrode is similar to bare electrode. So the dsDNA-modified electrode is employed as a sensitive biosensor for the detection of mifepristone. A linear dependence of the peak currents on the concentration is observed in the range 2.0 x 10(-7) approximately 2.0 x 10(6) mol/L, with a detection limit of 1.0 x 10(-7) mol/L. The relative standard deviation is 4.3% for six successive determinations of 1.0 x 10(6) mol/L mifepristone. The determination of mifepristone tablets is carried out and satisfactory results are obtained.


Assuntos
Técnicas Biossensoriais , Anticoncepcionais Hormonais Pós-Coito/análise , DNA , Mifepristona/análise , Carbono , Eletroquímica , Eletrodos , Indicadores e Reagentes
9.
Hum Reprod ; 5(5): 505-9, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2394783

RESUMO

Twenty-one castrated oestrogen-primed Wistar rats, which were 2-months-old, were injected via the jugular vein with 100 mu Ci/100 g body weight of [3H]RU 486 or [3H]progesterone. Some of these received unlabelled compounds for competition studies. Samples of reproductive tract, pituitary and hypothalamus were excised after 15 min. The 4-microns frozen sections were processed for thaw-mounted autoradiography. The exposure time of the autoradiogram was approximately 6 months. After the injection of [3H]RU 486 and [3H]progesterone, the nuclear concentration of radioactivity was most distinct in muscular and stromal cells of the uterus, and the epithelial nuclei of lumina and glands showed weak labelling. Nuclear localization was also observed in muscle cells of the vagina, cervix and oviduct. After injection of [3H]progesterone, the radioactivity was found in the nuclei and cytoplasm of anterior pituitary cells and some cells showed a preferential nuclear concentration of radioactivity. The distribution of [3H]RU 486 in the anterior pituitary was more extensive than that of [3H]progesterone. In the hypothalamus, specific localization of [3H]RU 486 and [3H]progesterone existed in neurones accumulated in the preoptic nucleus, preoptic suprachiasmatic nucleus and the periventricular nucleus. No localization was found in the diaphragm. Pretreatment with RU 486, but not with dexamethasone, reduced the nuclear concentration of radioactivity of [3H]progesterone in the vagina, uterus, oviduct, pituitary and hypothalamus. The nuclear concentration of radioactivity after injection of [3H]RU 486 was also decreased by preinjection with progesterone. The autoradiographic results suggest that RU 486 and progesterone competed for the specific binding site (possibly a progesterone receptor) in the target cells at the levels of the uterus, pituitary and hypothalamus in vivo.


Assuntos
Hipotálamo/análise , Mifepristona/análise , Hipófise/análise , Progesterona/análise , Útero/análise , Animais , Autorradiografia , Núcleo Celular/análise , Citoplasma/análise , Dexametasona/farmacologia , Epitélio/análise , Epitélio/ultraestrutura , Feminino , Hipotálamo/ultraestrutura , Mifepristona/farmacocinética , Músculos/análise , Músculos/ultraestrutura , Ovariectomia , Hipófise/ultraestrutura , Adeno-Hipófise/análise , Progesterona/farmacocinética , Progesterona/farmacologia , Ratos , Ratos Endogâmicos , Distribuição Tecidual , Trítio , Útero/ultraestrutura
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