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1
Penna, Heloisa M. "A estrofe alcaica e a genialidade da Ode I,37." Aletria: Revista de Estudos de Literatura 22, no. 1 (April 30, 2012): 92–110. http://dx.doi.org/10.17851/2317-2096.22.1.92-110.
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Das 37 odes escritas em versos alcaicos por Horácio, a I,37 é uma das mais belas. Essa estrofe tem como característica a variedade das linhas métricas: as duas primeiras linhas são divididas em dois cola, jâmbico e datílico; a terceira é uma linha jâmbica e a quarta, uma linha datílica. Essa estrutura favorece as expressões exortativas e cívicas. Na Ode I,37, Horácio explora as características da estrofe alcaica selecionando, para cada parte do verso, palavras e expressões convenientes à impressão rítmica dessa diferenciada estrutura. Horácio escolhe suas palavras, ritmos e imagens conscientemente e com grande cuidado.
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Thamos, Márcio. "Propércio 1.1, 1.2, 1.7, 1.12: algumas elegias d’O Livro de Cíntia." Letras Clássicas, no. 10 (December 18, 2006): 215. http://dx.doi.org/10.11606/issn.2358-3150.v0i10p215-224.
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Apresentam-se a seguir alguns poemas traduzidos d’<em>O Livro de Cíntia</em>, as elegias 1, 2, 7 e 12, em que, experimentalmente, procurou-se adotar um possível padrão de equivalência ao dístico elegíaco, valendo-se de uma pequena estrofe vernácula composta de dois decassílabos seguidos de um hexassílabo, sem qualquer preocupação com rimas.
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Ghirardi, Pedro Garcez. "Notas sobre a questão das rimas na tradução do Orlando Furioso." Cadernos de Literatura em Tradução, no. 7 (November 1, 2006): 241–47. http://dx.doi.org/10.11606/issn.2359-5388.i7p241-247.
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É sabido que traduzir poetas clássicos é defrontar-se muitas vezes com o problema da transposição da rima. Isto é o que ocorre no Orlando Furioso de Ariosto. Construído em oitavas de decassílabos (ou hendecassílabos, pelo cômputo italiano), os versos de cada estrofe do poema se dispõem em rimas alternadas (os seis primeiros) e emparelhadas (os dois últimos).
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Mattos, Ricardo Mendes. "A poesia portuguesa no Samba de Roda do Recôncavo Baiano." Letrônica 11, no. 1 (June 27, 2018): 91. http://dx.doi.org/10.15448/1984-4301.2018.1.27787.
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Apresenta-se exemplos da influência da poesia popular portuguesa nos versos cantados no Samba de Roda do Recôncavo Baiano, a partir da comparação entre versões do cancioneiro popular português e gravações fonográficas do Samba de Roda. Conclui-se que a poesia popular portuguesa fornece não apenas elementos poéticos referentes a estrofe e a rima, como reconhecido por estudiosos, mas também conteúdos verbais em versos idênticos.
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Eggensperger, Klaus. "Schillers Gott Bemerkungen zu den “Göttern Griechenlands”." Pandaemonium Germanicum, no. 9 (December 17, 2005): 63. http://dx.doi.org/10.11606/1982-8837.pg.2005.73558.
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No poema “Die Götter Griechenlands”, Schiller elabora a diferença entre uma Grécia clássica idealizada, entendida como totalidade orgânica em harmonia consigo mesmo, e a Europa moderna do sec. XVIII com sua fragmentação e seu materialismo temível. Afirma-se que o autor está menos condenando o cristianismo do que enfatizando a função da arte. Na última estrofe, a beleza da arte é oferecida como último recurso de preservar sentido e humanidade. O status quase religioso que Schiller reserva para a arte é crucial para entender o pensar literário e cultural na Alemanha do sec. XIX.
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Da Silva Moreira, Daniel. "Horácio, Odes, I.37. Apresentação e tradução." Nuntius Antiquus 11, no. 2 (February 5, 2016): 143–52. http://dx.doi.org/10.17851/1983-3636.11.2.143-152.
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O presente texto propõe uma nova tradução versificada da ode I.37, do poeta romano Horácio (65 a.C. – 8 a.C.). Precede-o uma breve contextualização do evento histórico evocado pelo poema, a batalha de Ácio (Actium) – travada em 2 de setembro de 31 a.C. no mar Jônico, próximo à cidade de Ácio, na província romana da Macedônia –, algumas notas que, baseadas em bibliografia atualizada sobre o tema, tratam sobre as estratégias discursivas escolhidas pelo poeta para representar, ou omitir, os personagens envolvidos na batalha, e, finalmente, algumas considerações, ainda que o mais sucintas possível, sobre a tradução da estrofe alcaica.
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Ketzer, Estevan. "Por uma ética do ritmo: A tradu(i)ção bíblica de Henri Meschonnic." Arquivo Maaravi: Revista Digital de Estudos Judaicos da UFMG 10, no. 19 (November 9, 2016): 47–61. http://dx.doi.org/10.17851/1982-3053.10.19.47-61.
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O presente ensaio questiona a teoria poética de Henri Meschonnic diante do seu trabalho tradutório, unindo assim a lingüística e a ética. Ao partir de um ponto incontornável diante da tradução da primeira estrofe do livro Gênesis/Bereshit. A linguagem encontrada desencadeia de opções textuais com forte base poética, fato este que o leva a examinar mais detidamente processos internos de assimilação da poesia na vida de seus intérpretes. O ritmo aparece como um elemento criativo inaudito diante da pretensa verdade da almejada pela ciência e a subjetividade que é partilhada pela revelação de elementos vocálicos como os te’amim presentes na língua hebraica.
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Osório, Julia Telésforo. "A biblioteca em versus de Rui Pires Cabral / The Rui Pires Cabral’s Biblioteca in Versus." Revista do Centro de Estudos Portugueses 39, no. 62 (January 22, 2020): 49. http://dx.doi.org/10.17851/2359-0076.39.62.49-62.
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Resumo: Neste artigo, apresento análises rítmico-formais de três poemas-colagens de autoria do poeta português contemporâneo Rui Pires Cabral, integrantes do livro Biblioteca de rapazes, publicado no ano de 2012. Neles, o desenvolvimento de seus respectivos temas é acompanhado de imagens que remetem, aos leitores, uma espécie de figuração dos campos semânticos então montados poeticamente, o que propicia dinamismo à linguagem verbal registrada em tais textos e às próprias conceituações dos termos teóricos “verso”, “estrofe” e “ritmo”, as quais, como se sabe, são fundamentais em matéria de poesia. O objetivo teórico-crítico deste texto é o de refletir sobre esse tipo de poemas junto da elaboração do entendimento conceitual dos termos poéticos mencionados, que são problematizados nos discursos literários dos dessa poesia-colagem, composta por meio do uso de imagens que, como dito, substanciam as dimensões temáticas desse tipo de enunciado artístico.Palavras-Chave: poema-colagem; poesia portuguesa contemporânea; Rui Pires Cabral; verso livre.Abstract: The purpose of this research is to introduce a rhytmic-formal analyze of three collage-poems written by Rui Pires Cabral, on his book Biblioteca de rapazes, published on 2012. In this edition, the themes are developted with images that refers a figuration of semantic fields then poetically builded. This kind of choice provides dynamism to the verbal language registred in such texts and to the concept of the theoretical terms, like verso, estrofe and ritmo. We all know that this concepts are fundamental in terms of poetry. Therefore, the theoretical-critical objective of this article is to discuss this type of poems and the elaboration of the conceptual compreehention of the previouslly mentioned poetic terms, problematized in the literary discourses of those collage-poems, composed by the use of images that build the thematic dimensions of this kind of artistic work.Keywords: collage-poems; Portuguese contemporary poetry; Rui Pires Cabral; free verse.
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Moreira, Daniel Da Silva. "OVÍDIO, AMORES, II.12." Belas Infiéis 5, no. 3 (December 30, 2016): 175–78. http://dx.doi.org/10.26512/belasinfieis.v5.n3.2016.11405.
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O poema que apresento em tradução pertence aos Amores, de Ovídio (43 a.C. – 17/18 d.C.), coleção de elegias de temática amorosa dada a público por volta do ano de 16 a.C. e composta empregando o dístico elegíaco, um tipo de estrofe mínima da poesia antiga, formada por um hexâmetro e um pentâmetro. Entre os muitos aspectos e temas amorosos tratados pelas elegias dos Amores, a II.12 é um poema de triunfo. Depois de vencidos os obstáculos que o separavam da amada, o amante comemora coroado com louros como aqueles dados aos generais vitoriosos e, à moda dos triunfos militares, relembra os estágios de sua conquista, fazendo passar em desfile uma recriação da narrativa de sua pequena guerra amorosa, em que exalta suas qualidades de soldado do exército de Cupido.
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Vieira, Brunno Vinícius Gonçalves. "Desejo e fúria de Ovídio pelas tabelas: Amores 1.11 e 1.12." Nuntius Antiquus 12, no. 2 (January 26, 2017): 289–302. http://dx.doi.org/10.17851/1983-3636.12.2.289-302.
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Apresenta-se, neste artigo, a tradução do díptico (Amores 1.11 e 1.12) precedida de uma introdução em que o tradutor busca apresentar as motivações práticas e teóricas subjacentes à sua execução. Desenvolve-se uma breve reflexão sobre a duplicidade e a desigualdade tanto dos versos quanto dos personagens que vivem duas diferentes situações de uma fábula amorosa. O díptico oferece dois lances opostos de uma tentativa de amor, sua esperança e seu fracasso. Desejava o poeta se declarar. Desejava o encontro. Desejava Amor em seu sentido carnal (1.11), mas recebe a negativa, caindo em fúria, não contra a amada, mas contra as dúplices tabuinhas (1.12), sendo essas últimas mais uma metonímia da dubiedade do gênero elegíaco como praticado por Ovídio. A tradução, em uma estrofe portuguesa composta por dois decassílabos seguidos de um hexassílabo, procura replicar poeticamente alguns aspectos sonoros, sintáticos e semânticos percebidos no texto de partida.
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Canário, Catarina, Mariana Matias, Vanessa Brito, Adriana O. Santos, Amílcar Falcão, Samuel Silvestre, and Gilberto Alves. "New Estrone Oxime Derivatives: Synthesis, Cytotoxic Evaluation and Docking Studies." Molecules 26, no. 9 (May 4, 2021): 2687. http://dx.doi.org/10.3390/molecules26092687.
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The interest in the introduction of the oxime group in molecules aiming to improve their biological effects is increasing. This work aimed to develop new steroidal oximes of the estrane series with potential antitumor interest. For this, several oximes were synthesized by reaction of hydroxylamine with the 17-ketone of estrone derivatives. Then, their cytotoxicity was evaluated in six cell lines. An estrogenicity assay, a cell cycle distribution analysis and a fluorescence microscopy study with Hoechst 3358 staining were performed with the most promising compound. In addition, molecular docking studies against estrogen receptor α, steroid sulfatase, 17β-hydroxysteroid dehydrogenase type 1 and β-tubulin were also accomplished. The 2-nitroestrone oxime showed higher cytotoxicity than the parent compound on MCF-7 cancer cells. Furthermore, the oximes bearing halogen groups in A-ring evidenced selectivity for HepaRG cells. Remarkably, the Δ9,11-estrone oxime was the most cytotoxic and arrested LNCaP cells in the G2/M phase. Fluorescence microscopy studies showed the presence of condensed DNA typical of prophase and condensed and fragmented nuclei characteristic of apoptosis. However, this oxime promoted the proliferation of T47-D cells. Interestingly, molecular docking studies estimated a strong interaction between Δ9,11-estrone oxime and estrogen receptor α and β-tubulin, which may account for the described effects.
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Duarte Fernandes dos Passos, Rogério. "A INTERPRETAÇÃO DE UMA ESTROFE DA CANÇÃO “BREATHE”, DO U2, COMO UMA EXPERIÊNCIA RELIGIOSA E EM BREVE DIREÇÃO À DOUTRINA ESPÍRITA." Revista Científica Semana Acadêmica, no. 189 (September 16, 2021): 1–23. http://dx.doi.org/10.35265/2236-6717-189-8513.
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The study aims to consider one of the stanzas of the song “Breathe”, from the Irish rock group U2, and, overcoming the simple delight and the commonly visible in the music pop scene, make out an analysis and interpretation according to the Spiritist doctrine, especially in one of its fundamentals: the reincarnation.
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Prado, João Batista Toledo. "Ritmo e expressividade do dístico elegíaco: Tibulo 1.3.1–4." Letras Clássicas 19, no. 2 (December 10, 2015): 114. http://dx.doi.org/10.11606/issn.2358-3150.v19i2p114-129.
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A partir da consciência de que sílabas longas e breves (cor)respondem-se mutuamente num sistema de oposições básicas, é imprescindível verificar o papel desempenhado por elas nas cadeias fonossintáticas que formam os pés métricos, função que elas só desempenham através de valores psicológicos investidos nas estruturas hieraquicamente organizadas do verso, geradas a partir da oposição básica que elas encetaram. Tais valores são as propriedades combinatórias que os segmentos do nível seguinte permitem, quais sejam os metros e, em seguida, os pés métricos que eles realizam ou integram, daí o verso e, eventualmente, a estrofe, de modo a estruturar o poema todo. Tendo em vista que se trata sempre de concatenação de elementos, o conjunto formado tenderá a gerar uma orientação, isto é, um sentido, que é a princípio um determinado ritmo poético. O ritmo, entretanto, é influenciado por outras ocorrências ao longo da cadeia fonossintática, como as cesuras que incidem sobre a linha do verso. A partir da passagem de Tibulo, 1.3.1–4, o presente texto propõe levar em conta tais fatores para analisar o andamento rítmico-melódico da unidade estrófica formada pelo dístico elegíaco, com especial enfoque nas possibilidades de escansão geradas pela cesura-diérese fixa do pentâmetro e suas consequências para a expressividade poética.
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Hobkirk, R., and Catherine A. Cardy. "The in vitro formation of sulfates and glucuronides of estrogens by adult and fetal ovine tissues." Canadian Journal of Biochemistry and Cell Biology 63, no. 8 (August 1, 1985): 785–91. http://dx.doi.org/10.1139/o85-100.
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Incubation of nanomolar concentrations of [3H]estrone with ovine liver slices from adult and fetal animals demonstrated, in particular, the production of estrogen sulfates together with smaller amounts of glucuronides, even although microsomal estrogen glucuronyltransferase (GT) and sulfatase activities were high, especially in adult tissue. [3H]Estriol was conjugated almost exclusively as sulfate under the same experimental conditions. Slices of maternal and fetal kidney medulla were also strikingly active in promoting estrogen sulfate production as were slices of fetal kidney cortex. Adult kidney cortex conjugated estrogen only in the glucuronide form. These data indicate the possibility that maternal and fetal liver and kidney might contribute to the high circulating level of estrone sulfate in the pregnant sheep. Through the use of [3H]estrone and [3H]estrone sulfate as substrates, it was possible to demonstrate that adult slices of kidney medulla possessed relatively low sulfatase, considerable sulfotransferase (ST), and virtually no GT activity, whereas cortex had high sulfatase, little or no ST, and low, though demonstrable, GT activity. The ST activity of kidney high-speed supernatants was stimulated by the presence of sulfhydryl groups, whereas that in liver was not. Enzymic reduction of estrone and (or) estrone sulfate by liver and kidney slices indicated that, in the former, 17α-reduction prevailed and, in the latter with the exception of the maternal medulla, 17β-reduction was the main pathway, particularly in the fetus.
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Hetemäki, Natalia, Hanna Savolainen-Peltonen, Matti J. Tikkanen, Feng Wang, Hanna Paatela, Esa Hämäläinen, Ursula Turpeinen, Mikko Haanpää, Veera Vihma, and Tomi S. Mikkola. "Estrogen Metabolism in Abdominal Subcutaneous and Visceral Adipose Tissue in Postmenopausal Women." Journal of Clinical Endocrinology & Metabolism 102, no. 12 (September 29, 2017): 4588–95. http://dx.doi.org/10.1210/jc.2017-01474.
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Abstract Context In postmenopausal women, adipose tissue (AT) levels of estrogens exceed circulating concentrations. Although increased visceral AT after menopause is related to metabolic diseases, little is known about differences in estrogen metabolism between different AT depots. Objective We compared concentrations of and metabolic pathways producing estrone and estradiol in abdominal subcutaneous and visceral AT in postmenopausal women. Design, Setting, Patients, and Interventions AT and serum samples were obtained from 37 postmenopausal women undergoing surgery for nonmalignant gynecological reasons. Serum and AT estrone, estradiol, and serum estrone sulfate (E1S) concentrations were quantitated using liquid chromatography-tandem mass spectrometry. Activity of steroid sulfatase and reductive 17β-hydroxysteroid dehydrogenase enzymes was measured using radiolabeled precursors. Messenger RNA (mRNA) expression of estrogen-converting enzymes was analyzed by real-time reverse transcription quantitative polymerase chain reaction. Results Estrone concentration was higher in visceral than subcutaneous AT (median, 928 vs 706 pmol/kg; P = 0.002) and correlated positively with body mass index (r = 0.46; P = 0.011). Both AT depots hydrolyzed E1S to estrone, and visceral AT estrone and estradiol concentrations correlated positively with serum E1S. Compared with visceral AT, subcutaneous AT produced more estradiol from estrone (median rate of estradiol production, 1.02 vs 0.57 nmol/kg AT/h; P = 0.004). In visceral AT, the conversion of estrone to estradiol increased with waist circumference (r = 0.65; P = 0.022), and estradiol concentration correlated positively with mRNA expression of HSD17B7 (r = 0.76; P = 0.005). Conclusions Both estrone and estradiol production in visceral AT increased with adiposity, but estradiol was produced more effectively in subcutaneous fat. Both AT depots produced estrone from E1S. Increasing visceral adiposity could increase overall estrogen exposure in postmenopausal women.
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Ursin, Giske, Shana L. Palla, Beth A. Reboussin, Stacey Slone, Carol Wasilauskas, Malcolm C. Pike, and Gail A. Greendale. "Post-Treatment Change in Serum Estrone Predicts Mammographic Percent Density Changes in Women Who Received Combination Estrogen and Progestin in the Postmenopausal Estrogen/Progestin Interventions (PEPI) Trial." Journal of Clinical Oncology 22, no. 14 (July 15, 2004): 2842–48. http://dx.doi.org/10.1200/jco.2004.03.120.
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Purpose Postmenopausal estrogen and progestin therapy (EPT) increases mammographic percent density and breast cancer risk substantially more than does estrogen therapy alone. We determined whether increases in serum estrone as a function of treatment predict increases in mammographic percent density. Methods We measured mammographic percent density and serum estrone levels in participants in the Postmenopausal Estrogen/Progestin Interventions Trial who were randomly assigned to receive conjugated equine estrogens (CEE) 0.625 mg/d; CEE and medroxyprogesterone acetate (MPA) 10 mg on days 1 to 12 per 28-day cycle; CEE and MPA 2.5 mg/d; or CEE and micronized progesterone (MP) 200 mg on days 1 to 12 per 28-day cycle. We used linear regression to determine whether serum estrone changes predicted mammographic percent density changes from baseline to 1 year. Results Mammographic percent density increased with increasing change in estrone level in the EPT groups, but not in the CEE group. Combined, the mammographic percent density in the three EPT groups demonstrated an absolute increase of 2.95% per 100 pg/mL increase in serum estrone level (P = .0003). The absolute increases were 4.09% (P = .0018) in the CEE + MPA continuous group, 2.79% (P = .0292) in the CEE + MPA cyclical group, and 1.40% (P = .36) in the CEE + MP group, but the differences among the EPT groups were not statistically significant. Conclusion Greater increase in serum estrone level as a function of treatment is a significant predictor of increase in mammographic percent density in women randomly assigned to the combination of estrogen and progestin.
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Folkerd, Elizabeth J., J. Michael Dixon, Lorna Renshaw, Roger P. A'Hern, and Mitch Dowsett. "Suppression of Plasma Estrogen Levels by Letrozole and Anastrozole Is Related to Body Mass Index in Patients With Breast Cancer." Journal of Clinical Oncology 30, no. 24 (August 20, 2012): 2977–80. http://dx.doi.org/10.1200/jco.2012.42.0273.
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Purpose To investigate whether suppression of plasma estradiol and estrone sulfate levels by the aromatase inhibitors (AIs) anastrozole and letrozole is related to body mass index (BMI) in postmenopausal women with early estrogen receptor (ER) –positive breast cancer. Recent studies have reported that the AI anastrozole has lower effectiveness than tamoxifen in women with high BMI. This effect with high BMI might hypothetically be a result of reduced inhibition of aromatase and suppression of plasma estrogen levels and might be overcome by the use of an increased dose of anastrozole or, alternatively, the use of a more potent AI such as letrozole. Patients and Methods Plasma estradiol and estrone sulfate levels from a highly sensitive radioimmunoassay were available for 44 postmenopausal patients who received anastrozole (1 mg per day) for 3 months followed by letrozole (2.5 mg per day) for 3 months or the opposite sequence. Correlations between the estrogen suppression by each AI and BMI were assessed. Results Baseline values of estradiol and estrone sulfate were significantly correlated with BMI (r = 0.57; P < .001, and r = 0.38; P = .006, respectively). Levels of estrogen in patients receiving treatment were greater at higher levels of BMI with both AIs, but although this was significant with letrozole (r = 0.35; P = .013, and r = 0.30; P = .035 for estradiol and estrone sulfate, respectively), it was not with anastrozole. Suppression of both estrogen types was greater with letrozole across the full range of BMIs in this study. Conclusion The suppressed levels of plasma estradiol and estrone sulfate in postmenopausal women with early ER-positive breast cancer treated with the AIs anastrozole and letrozole are related to BMI.
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Mansur, Antonio de Padua, Tereza Cristina B. F. Silva, Julio Yoshio Takada, Solange Desirée Avakian, Célia Maria C. Strunz, Luiz Antonio Machado César, José Mendes Aldrighi, and José Antonio F. Ramires. "Long-Term Prospective Study of the Influence of Estrone Levels on Events in Postmenopausal Women with or at High Risk for Coronary Artery Disease." Scientific World Journal 2012 (2012): 1–6. http://dx.doi.org/10.1100/2012/363595.
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Background. The link between endogenous estrogen, coronary artery disease (CAD), and death in postmenopausal women is uncertain. We analyzed the association between death and blood levels of estrone in postmenopausal women with known coronary artery disease (CAD) or with a high-risk factor score for CAD.Methods. 251 postmenopausal women age 50–90 years not on estrogen therapy. Fasting blood for estrone and heart disease risk factors were collected at baseline. Women were grouped according to their estrone levels (<15 and ≥15 pg/mL). Fatal events were recorded after5.8±1.4years of followup.Results. The Kaplan-Meier survival curve showed a significant trend (P=0.039) of greater all-cause mortality in women with low estrone levels (<15 pg/mL). Cox multivariate regression analysis model adjusted for body mass index, diabetes, dyslipidemia, family history, and estrone showed estrone (OR=0.45;P=0.038) as the only independent variable for all-cause mortality. Multivariate regression model adjusted for age, body mass index, hypertension, diabetes, dyslipidemia, family history, and estrone showed that only age (OR=1.06;P=0.017) was an independent predictor of all-cause mortality.Conclusions. Postmenopausal women with known CAD or with a high-risk factor score for CAD and low estrone levels (<15 pg/mL) had increased all-cause mortality.
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Power, S. G. A., and J. R. G. Challis. "Tissue-specific concentration changes of estrone and estradiol during spontaneous and ACTH-induced parturition in sheep." Canadian Journal of Physiology and Pharmacology 65, no. 2 (February 1, 1987): 130–35. http://dx.doi.org/10.1139/y87-026.
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Changes in estrogen production are considered important in the sequence of events leading to parturition. We sought tissue-specific changes in the concentration of unconjugated estrone (E1) and estradiol (E2) in intrauterine fetal (amnion, chorion) and maternal (endometrium, myometrium) tissues during normal pregnancy, labour, and ACTH-induced labour in sheep. The mean concentrations of E1 and E2 in the fetal membranes were higher than in endometrium and myometrium. In amnion there were no consistent changes in estrone concentrations with gestation, although estradiol concentrations increased between day 130 and term. In the endometrium there were increases in both estrone and estradiol between day 100 and term, whereas in the myometrium increases in the concentrations of E1 and E2 occurred between days 130–135 and term. Animals showing a labourlike pattern of uterine contractions after intrafetal ACTH administration did not show significant differences in estrone or estradiol concentrations in amnion, chorion, or endometrium compared with saline-infused controls. However, there was a progressive increase in the concentration of estrone and estradiol in the myometrium during ACTH-induced labour. We conclude that changes in the concentrations of estrone and estradiol in intrauterine tissues vary between the tissues studied and the two estrogens. In general, estrogen concentrations increased towards term, but this trend was more marked in the maternal than fetal tissues. The changes in estrone concentrations in myometrium, but not in the other tissues, were replicated during ACTH-induced labour. Our results would be compatible with the suggestion that tissue-specific changes in estrogen concentrations may contribute to the local intrauterine steroid milieu during pregnancy and at term.
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Hirayama, Hiroki, Ken Sawai, Satoru Moriyasu, Muneyuki Hirayama, Yuji Goto, Etsushi Kaneko, Akio Miyamoto, Koichi Ushizawa, Toru Takahashi, and Akira Minamihashi. "Excess estrogen sulfoconjugation as the possible cause for a poor sign of parturition in pregnant cows carrying somatic cell clone fetuses." REPRODUCTION 136, no. 5 (November 2008): 639–47. http://dx.doi.org/10.1530/rep-08-0157.
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We conducted this study to elucidate a factor causing a poor sign of parturition and prolonged gestation, which is frequently observed in cows carrying somatic clone fetuses. Pre-partum rises in concentrations of plasma estrone and estradiol-17β in the recipient cows pregnant with clones were subtle. By contrast, the plasma concentration of estrone sulfate in clone pregnancies increased gradually from pre-initiation of parturition induction whereas control cows that receivedin vivo-derived embryos showed a significant increase at parturition. Therefore, in clone pregnancies, the ratio of estrone/estrone sulfate was low during the pre-partum period compared with control. Messenger RNA expression of estrogen sulfotransferase (SULT1E1) in the placenta at parturition was significantly higher in clone pregnancies than control pregnancies and was localized in binucleate cells (BNC).SULT1E1mRNA abundance was negatively and positively correlated with concentrations of maternal estrone and estrone sulfate at parturition respectively. Messenger RNA expressions of estrogen sulfatase (STS) and aromatase (CYP19) were similar between clone and control pregnancies and were localized in BNC and caruncular epithelial cells.STSandCYP19mRNA abundances showed positive correlations with maternal estradiol-17β concentration. The population of BNC in the placenta did not differ between clone and control pregnancies. Plasma cortisol concentration of vaginally delivered newborn clone calves was comparable with those of control, although cesarean section delivered clone calves showed a low concentration. These results suggest that excess estrogen sulfoconjugation is the reason for the perturbed low ratio of active to inactive estrogens and the resulting hormonal imbalance contributes to the lack of overt signs of readiness for parturition in cows pregnant with clones.
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Makker, A., F. W. Bansode, V. M. L. Srivastava, and M. M. Singh. "Antioxidant defense system during endometrial receptivity in the guinea pig: effect of ormeloxifene, a selective estrogen receptor modulator." Journal of Endocrinology 188, no. 1 (January 2006): 121–34. http://dx.doi.org/10.1677/joe.1.06324.
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The role of the antioxidant defense system during endometrial receptivity, a phenomenon crucial for implantation and decidualization, and the effect of ormeloxifene, a selective estrogen receptor modulator, were investigated in the guinea pig, a laboratory mammalian species with interstitial implantation and a long functional luteal phase during each estrous cycle. A sharp rise in the activity of superoxide dismutase (SOD) in both antimesometrial (AM) and mesometrial segments and peroxidase in the AM segment of the uterus was observed on the day of maximal endometrial receptivity. Pretreatment with ormeloxifene resulted in loss of endometrial responsiveness, as evidenced by inhibition of trauma-induced decidualization and the activity of ornithine decarboxylase, a marker of tissue growth and repair. This was associated with a decrease in SOD and estradiol dehydrogenase activities, with corresponding increases in estrone dehydrogenase activity and stimulation of uterine luminal epithelial cell height and a distension of the uterine and glandular lumen. A decrease in peroxidase activity was observed only in the AM segment of the uterus on the imminent day of maximal endometrial receptivity. No effect on peripheral plasma progesterone concentration or surface ultrastructure was evident. These findings demonstrate that SOD plays an important role, with peroxidase having a supplementary role, in the first line of defense against superoxide anion radicals during the period of maximal endometrial receptivity in the guinea pig. Inhibition of endometrial receptivity and decidualization by ormeloxifene administered during the pre-receptive phase appears to be due to a depressed antioxidant defense system via dysregulation of redox-sensitive signaling, resulting in altered cellular toxicity due to increased superoxide radicals, and might contribute to the contraceptive action of ormeloxifene. This might be related to its estrogen antagonistic activity and/or decreased bioavailability of estradiol at a cellular level due to its increased metabolism to biologically less-active estrone via activation of estradiol-17 beta-hydroxysteroid dehydrogenase and suppression of estrone-17 beta-hydroxysteroid dehydrogenase.
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Ruchiraset, Apaporn, and Sopa Chinwetkitvanich. "Estrogens Removal by Sludge from Enhance Biological Phosphorus Removal System." Advanced Materials Research 931-932 (May 2014): 246–50. http://dx.doi.org/10.4028/www.scientific.net/amr.931-932.246.
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This study was to investigate the removal of four estrogens in enhance biological phosphorus removal (EBPR) system. Sludge from four EBPRs were used to investigate both of anaerobic and aerobic conditions. Results showed that EBPR could remove estrogen both under anaerobic and aerobic conditions. In anaerobic condition, estrogens removals were in the range of 7692% for E1 (estrone), 5890% for E2 (17β-estradiol), 4363% for E3 (estrol), and 6288% for EE2 (17α-ethinylestradiol). In aerobic phase, removal of estrogens were ranging from 7996% for E1, 7696% for E2, 3664% for E3, and 5796% of EE2. Sorption onto sludge was the main mechanism of estrogens removal in comparison with biodegradation, which their sorption:biodegradation ratios were around 0.9:0.1 and 0.8:0.2 in anaerobic and aerobic conditions, respectively. Moreover, biotransformation of E2 to E1 was found in every E2-batch experiments that used active sludge.
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Lotinun, S., KC Westerlind, RT Turner, and RT Turner. "Tissue-selective effects of continuous release of 2-hydroxyestrone and 16alpha-hydroxyestrone on bone, uterus and mammary gland in ovariectomized growing rats." Journal of Endocrinology 170, no. 1 (July 1, 2001): 165–74. http://dx.doi.org/10.1677/joe.0.1700165.
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2-Hydroxyestrone (2-OHE(1)) and 16alpha-hydroxyestrone (16alpha-OHE(1)) have been reported to be risk factors for negative bone balance and breast cancer, respectively. The roles of these two metabolites of estrone as estrogen agonists or antagonists with respect to estrogen target tissues, or both, are poorly defined. The purpose of this study was to characterize metabolite and tissue-specific differences between the actions of hydroxylated estrones on selected reproductive and non-reproductive estrogen target tissues in growing rats. First, the effects of ovariectomy were determined. Ovariectomy had the expected effects, including increases in all dynamic bone measurements at the proximal tibial epiphysis, without induction of bone loss. Second, ovariectomized growing rats were continuously treated for 3 weeks with 2-OHE(1), 16alpha-OHE(1), 17beta-estradiol (E(2)), a combination of E(2) and 2-OHE(1) (E(2)+2-OHE(1)), or a combination of E(2) and 16alpha-OHE(1) (E(2)+16alpha-OHE(1)), using controlled release subcutaneous implanted pellets containing 5 mg 2-OHE(1), 5 mg 16alpha-OHE(1), 0.05 mg E(2) or placebo. E(2) reduced body weight gain and radial and longitudinal bone growth as well as indices of cancellous bone turnover, and increased serum cholesterol, uterine wet weight and epithelial cell height, and proliferative cell nuclear antigen labeling in mammary gland. The hydroxylated estrones did not alter uterine wet weight and 16alpha-OHE(1) antagonized the E(2)-stimulated increase in epithelial cell height. 2-OHE(1) had no effect on cortical bone, whereas 16alpha-OHE(1) was an estrogen agonist with respect to all cortical bone measurements. 16alpha-OHE(1) also behaved as an estrogen agonist with respect to serum cholesterol and cancellous bone measurements. 2-OHE(1) had no effect on most E(2)-regulated indices of cancellous bone growth and turnover, but was a weak estrogen agonist with respect to mineral apposition rate and bone formation rate. Neither estrogen metabolite influenced body weight gain. Third, weanling rats were treated for 1 week with vehicle, E(2) (200 microg/kg per day) or 16alpha-OHE(1) (30, 100, 300, 1000 and 3000 microg/kg per day) to confirm uterotropic effects of daily subcutaneous (s.c.) administration of 16alpha-OHE(1). 16alpha-OHE(1) increased uterine weight in a dose-response manner to values that did not differ from rats treated with E(2). We conclude that the estrogen metabolites 2-OHE(1) and 16alpha-OHE(1) have target tissue-specific biological activities which differ from one another as well as from E(2). These findings add further support to the concept that there are several classes of estrogens with distinct biological activities. Furthermore, differences in the route of administration could influence the tissue specificity of estrogen metabolites.
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Kurniawan, Sukurna, Ristika Handarini, and Elis Dihansih. "GIVING RESPONSE GNRH HORMONE, ESTROGEN, PROGESTERONE AND PROSTAGLANDIN IN ESTRUS SYNCHRONIZATION IMPLEMENTATION ESTROUS COW RECIPIENT FRIESIAN HOLSTEIN." JURNAL PETERNAKAN NUSANTARA 4, no. 2 (January 10, 2019): 93. http://dx.doi.org/10.30997/jpnu.v4i2.1540.
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This study aimed to test the effectiveness of the injection of a combination hormone GnRH, estrogen, progesterone and prostaglandin on response of estrus, onset estrus and duration estrus FriesianHolstain (FH) recipient dairy cattle. This study was used 15 recipient cows not pregnant, were divided into three treatment methods of synchronization of estrus and each treatment consisted of 5 cattle. Recipient cow estrus response after injection of the hormone combination estrus synchronization with all three treatments show symptoms of estrous. The percentage of estrous cows FH overall recipient reaches 100%, showed that the treatment effect is very good and effective way to bully the onset of estrous cows recipient FH. The results of data analysis using Chi-Square showed no significant difference among all treatments. It was concluded, that synchronization of estrous FHcow recipients using GnRH hormone, estrogen, progesterone and prostaglandin as good in all of the parameters.Keywords: estrous synchronization, GnRH, estrogen, progesterone, prostaglandin.
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Ivanov, Anton, Sebastian Boldt, Zaib un Nisa, Syed Jawad Ali Shah, Peter Ehlers, Alexander Villinger, Gyula Schneider, et al. "Synthesis and phosphatase inhibitory activity of 3-alkynylestrones and their derivatives." RSC Advances 6, no. 14 (2016): 11118–27. http://dx.doi.org/10.1039/c5ra25558a.
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Lust, M., J. Makinia, and H. D. Stensel. "A mechanistic model for fate and removal of estrogens in biological nutrient removal activated sludge systems." Water Science and Technology 65, no. 6 (March 1, 2012): 1130–36. http://dx.doi.org/10.2166/wst.2012.958.
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Two estrogen fate and transformation models were integrated with a comprehensive activated sludge model (ASM) to predict estrogen removal based on biomass and solids production. Model predictions were evaluated against published full-scale plant data as well as results from a laboratory-scale sequencing batch reactor (SBR) fed synthetic wastewater. The estrogen fate model relating the rate of total estrogen degradation to soluble estrogen concentrations successfully predicted estrogen removals when compared with measured concentrations. Model fit 17α-ethinylestradiol (EE2) biodegradation rate constant was 19 to 43% of the estrone (E1) value and 31 to 72% of the 17β-estradiol (E2) value.
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Römer, Wolfgang, Michael Oettel, and Sigfrid Schwarz. "Scavestrogen sulfamates: correlation between estrone sulfatase inhibiting and antioxidant effects." Canadian Journal of Physiology and Pharmacology 76, no. 2 (February 1, 1998): 99–109. http://dx.doi.org/10.1139/y98-005.
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In the present study estrone sulfatase (steryl-sulfatase; EC 3.1.6.2) and phenylsulfatase (arylsulfatase B; EC 3.1.6.1) inhibiting as well as antioxidant effects exerted by ring B,C unsaturated sulfamates of estrone (J 1025), 17 beta -estradiol (J 1054, J 1059, J 1067), and 17 alpha -estradiol (J 1051, J 1064, J 1065) were examined as compared with their parent compounds, J 994, J 995, and J 1050, using six different in vitro models: (i) estrone sulfatase activity in human placental microsomes, (ii) phenylsulfatase activity isolated from Helix pomatia, (iii) Fenton reaction driven lipid peroxidation in rat synaptosomes, (iv) Fe(II)-chelating activities, (v) formation of superoxide anion radicals, and (vi) total antioxidative activities. Ring B,C unsaturated estrogen (so-called scavestrogen) sulfamates were found to act as potent inhibitors of the following enzyme activities and generated radicals: estrone sulfatase, phenylsulfatase, lipid peroxyl, and superoxide anion. In addition, scavestrogen sulfamates were able to influence the iron redox chemistry and total antioxidative activities. These findings indicate that relatively minor modifications in the chemical structure of classical steroid sulfamates can preserve or enhance their estrone sulfatase inhibiting properties and, simultaneously, amplify their antioxidant capacity to a great extent. Taken together, our data suggest that scavestrogen sulfamates such as J 1025, J 1051, or J 1054 (17 beta -dihydroequilenin sulfamate) may serve as a very promising basis for the development of steroid-derived estrone sulfate - sulfatase inhibitors characterized by promising estrone sulfatase inhibiting activities in combination with a "good" antioxidant potency.Key words: estrogen 3-O-sulfamates, estrone sulfatase, phenylsulfatase, lipid peroxidation, iron redox chemistry, human placental microsomes, radical scavenging effects.
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Purinton, Scott C., Howard Newman, Maria I. Castro, and Charles E. Wood. "Ontogeny of estrogen sulfatase activity in ovine fetal hypothalamus, hippocampus, and brain stem." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 276, no. 6 (June 1, 1999): R1647—R1652. http://dx.doi.org/10.1152/ajpregu.1999.276.6.r1647.
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Ovine parturition is initiated by increases in fetal hypothalamus-pituitary-adrenal (HPA) axis activity, which in turn increase placental estrogen biosynthesis and ultimately increase uterine contractility. In addition to the action in the uterus, estrogens augment fetal ACTH secretion. In late gestation, estrone sulfate is more abundant in fetal plasma than is unconjugated estrone. We studied hypothalamus, hippocampus, and brain stem tissue from fetal, neonatal, and adult sheep to test the hypothesis that the ovine brain contains estrogen sulfatase activity. We found that the activity in the hippocampus was significantly increased in late-gestation fetuses compared with both younger and older animals. No significant change in either hypothalamus or brain stem was revealed; however, the activity in all brain areas was high. Immunohistochemistry revealed the presence of estrogen sulfatase in the paraventricular nucleus of the hypothalamus, the nucleus of the solitary tract, and the rostral ventrolateral medulla. We conclude that ovine fetal hypothalamus, hippocampus, and brain stem contain estrogen sulfatase activity and that the activity in the hippocampus is developmentally regulated.
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Raeside, James I., Chad R. Wilkinson, and Gabrielle Farkas. "Ontogenesis of estrogen secretion by porcine fetal testes." Acta Endocrinologica 128, no. 6 (June 1993): 549–54. http://dx.doi.org/10.1530/acta.0.1280549.
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High levels of estrogen secretion is a characteristic of steroidogenesis in the pig testis in both the adult and newborn male. We have now examined the ability of fetal gonads to secrete estrogens, and compared it with testosterone secretion during prenatal development. Fetuses were recovered from sows (N=33) at 27–114 (term) days of gestation. Gonads were removed for organ culture in TC-199 medium, or used as minced tissues or free cell preparations when taken later in development. Organ cultures were maintained for 96 h with luteinizing hormone added for the last 72 h for one gonad of each pair. Estrone, estradiol-17β and testosterone were measured by radioimmunoassay in media samples. Trace amounts of estrone were detected almost as early as testosterone secretion commenced, but quantities sufficient for confirmation by radioimmunoassay after chromatography were not seen until day 35 of gestation. Estrogen production increased to >0.37 nmol·gonad−1·4 h−1 at term. Testosterone secretion in organ culture was increased by luteinizing hormone but no effect was seen on estrone levels for the first half of pregnancy. Thus, estrogen secretion is a feature of steroidogenesis in the porcine testes even in the early stages of fetal development.
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Park, Y. S., S. H. Yang, S. M. Park, S. J. Kim, and J. B. Kim. "118 DEVELOPMENT AND EVALUATION OF A TIME-RESOLVED FLUORESCENCE IMMUNOASSAY FOR ESTRONE-1-SULFATE IN URINE AS A TOOL FOR DIAGNOSIS OF EARLY PREGNANCY IN SWINE." Reproduction, Fertility and Development 20, no. 1 (2008): 139. http://dx.doi.org/10.1071/rdv20n1ab118.
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Early identification of pregnancy or non-pregnancy in sows is considered very important, as the management of sows during the post service period is crucial if the breeding efficiency of a herd is to be maximized. Studies of steroid hormones in pregnant sows showed that there was a significant increase in plasma estrone-1-sulfate concentration by the 16th day of gestation, which reaches peak values between Days 23 and 30 of gestation. Since plasma estrone-1-sulfate concentrations are high between Days 23 and 30 of pregnancy, its determination has been used as a means for early pregnancy diagnosis and monitoring fertility in sows. However, the application of the method in pig farms on a routine basis remains restricted because blood sampling is difficult and disturbs the animals. The present study describes the development of a simple and reliable time-resolved fluorescence immunoassay (TR-FIA) method for the estimation of estrone-1-sulfate in swine urine, which was assessed as a means for early diagnosis of pregnancy and monitoring fertility in sows. We demonstrated cross activity between Anti-estrone-1-glucuronide antibody (Clone 155) and estrone-1-sulfate. The method is based on a direct competitive heterogeneous immunoassay by the typical procedure of competitive immunocomplex formation. For detection of estrone-1-sulfate, anti-estrone-1-glucuronide antibody (Clone 155) was first coated on polystyrene microplates, and estrone-1-sulfate was captured by the primary antibody with estrone-1-glucuronide labeled with europium. The immunocomplex was subsequently dissociated by the enhancement solution containing Triton X-100, acetic acid, and chelators. The free europium was detection by DELFIA 1420 detector (Perkin-Elmer Life Sciences, Waltham, MA, USA). The fluorescence intensity of free europium at 613 nm was proportional to the logarithm of the concentration of estron-1-sulfate in a dynamic range of 0.078~10 ng mL–1. Intra-assay variation for estrone-1-sulfate was 4%. The limit of quantification was 100 pg mL–1. The mean estrone-1-sulfate concentration was significantly higher in pregnant sows (15.6 � 5.3 ng mL–1) than in non-pregnant sows and in sows in estrus (0.74 � 0.44 ng mL–1). Taking the concentration of 20 pg mL–1 as a cut-off, all cases of non-pregnant sows and sows in estrus were negative. Urine estrone-1-sulfate concentrations in pregnant sows at 23-day intervals post-service were 14~16 ng mL–1. According to the results of our field trial, urine estrone-1-sulfate concentrations are very low during estrus and remain low in non-pregnant sows at different stages of the estrous cycle, whereas the concentration increases significantly during specific stages of pregnancy at 23-day intervals. It is concluded that the satisfactory sensitivity of the present assay in combination with the good correlation for pregnancy from the present field trial makes this method a very useful technique for early pregnancy diagnosis in swine; the simplicity of urine sampling makes also it suitable for practical use.
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Olisov, D. A., V. V. Chagovets, N. L. Starodubtseva, A. A. Smetnik, V. V. Rodionov, V. V. Kometova, K. S. Chingin, and V. E. Frankevich. "Measurement of Breast Tissue Estrogens by Liquid Chromatography-tandem Mass Spectrometry." Biomedical Chemistry: Research and Methods 4, no. 2 (2021): e00147. http://dx.doi.org/10.18097/bmcrm00147.
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Although estrogen contribution estrogen to breast cancer development is not fully understood, an effective method of their measurement, in the mammary gland might provide additional insight. In this study, we have developed a LC-MS/MS method of simultaneous quantification of estrone and estradiol in breast tissue samples. Analytes were extracted with methyl tert-butyl ether by sonication and derivatized with dansyl chloride. Estrogens were analyzed by liquid chromatography-tandem mass spectrometry with an electrospray ionization source. Accuracy and precision were better than 20% for most concentrations. Although estrone and estradiol levels in normal and malignant breast tissue samples analyzed using our method insignificantly differed. The method developed may be used in further studies aimed at evaluating a role estrogens in breast cancer risk.
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Zarghi, Mohammad Hasan, Aliakbar Roudbari, Sahand Jorfi, and Neamat Jaafarzadeh. "Removal of Estrogen Hormones (17β-Estradiol and Estrone) from Aqueous Solutions Using Rice Husk Silica." Chemical & biochemical engineering quarterly 33, no. 2 (2019): 281–93. http://dx.doi.org/10.15255/cabeq.2018.1542.
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The aim of this study was to investigate the removal of estrogen hormones (17β-estradiol and estrone) from aqueous solutions using rice husk extracted silica. Rice husk was collected from rice factories in Mazandaran province (Iran) and the adsorbent was prepared in a furnace at 800 °C for 4 h, after acid leaching with hydrochloric and sulfuric acid mixture. Optimal operating parameters for estrogen removal were determined, including initial pH values (4–9), adsorbent dosages (0.5, 1, 1.5, and 2 g L–1), contact times (30, 60, 90, and 120 min), and initial concentrations of 17β-estradiol and estrone (10, 40, 70 and 100 ng L–1); one-factor-at-a-time method was used. The method of electrochemiluminescence was used to measure the concentration of hormones. Kinetic adsorption models and adsorption isotherms were also studied. The maximum removal efficiency (%) of 17β-estradiol (E2) and estrone (E1) hormones of 95.5 and 93.1 %, respectively, was obtained at optimal conditions of pH 4, 1.5 g L–1 of adsorbent dosage, 60 min of contact time and 10 ng L–1 initial concentrations of E2 and E1. Pseudo first-order kinetic model and Langmuir adsorption isotherm had the best fit with experimental data for both estrogen hormones, following nonlinear regression procedure. Rice husk silica could be considered as effective and accessible adsorbent for removal of estrogenic hormones.
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Dabrosin, Charlotta. "Increased extracellular local levels of estradiol in normal breast in vivo during the luteal phase of the menstrual cycle." Journal of Endocrinology 187, no. 1 (October 2005): 103–8. http://dx.doi.org/10.1677/joe.1.06163.
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Estrogen exposure is a major risk factor for breast cancer. Tissue estrogen originates from the ovaries but a significant portion is also produced by enzyme activity locally in the breast itself. How these enzymes are regulated is not fully understood. The extracellular space, where the metabolic exchange and cell interactions take place, reflects the environment that surrounds the epithelium but there has been no previous study of hormone concentrations in this compartment. In the present study microdialysis was used to measure extracellular estrogen concentrations in breast tissue and abdominal subcutaneous fat in 12 healthy women in vivo. It was found that women with high plasma progesterone levels had significant increased levels of estradiol in breast tissue compared with fat tissue (breast tissue 168 ± 6 pM; subcutaneous fat, 154 ± 5 pM; P<0.05), whereas women with low plasma progesterone exhibited no difference. Moreover, there was a significant correlation between local breast tissue estradiol and plasma progesterone levels (r=0.709, P<0.01). There was no difference in estrone sulphate in breast and fat tissue regardless of progesterone levels. Estrone was not detectable. The results in this study suggest that progesterone may be one regulator in the local conversion of estrogen precursors into potent estradiol in normal breast tissue.
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Wood, Charles E., Kelly E. Gridley, and Maureen Keller-Wood. "Biological Activity of 17β-Estradiol-3-Sulfate in Ovine Fetal Plasma and Uptake in Fetal Brain." Endocrinology 144, no. 2 (February 1, 2003): 599–604. http://dx.doi.org/10.1210/en.2002-220764.
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In sheep, the fetal hypothalamus-pituitary-adrenal axis plays a central role in the initiation of parturition. We have reported that estradiol dramatically increases the activity of the fetal hypothalamus-pituitary-adrenal (HPA) axis. Sulfoconjugated estrogens are known to circulate in high concentrations in fetal plasma. We have reported the expression and abundant activity of steroid sulfatase within the fetal brain regions important for HPA axis control, and we have proposed that sulfoconjugated estrogens in fetal plasma are deconjugated (and therefore converted to a biologically active form) in fetal brain. The present study was designed to test the hypothesis that exogenous estradiol-3-sulfate stimulates HPA axis activity in late gestation fetal sheep and that it is concentrated by fetal brain tissue. We infused estradiol-3-sulfate iv into fetal sheep (125–135 d gestation; term = 147 d) at rates of 0, 0.25, and 1.0 mg/d for 5 d and performed serial sampling of fetal blood before and at the end of the infusion periods. Infusions increased fetal plasma estradiol-3-sulfate concentrations and produced dose-related increases in HPA axis activity. The action of the steroid on the fetal brain was also demonstrated as dose-related increases in the abundance of Fos in fetal cerebellum. In a second study we measured the uptake of sulfoconjugated and unconjugated estrogen (estrone-3sulfate and estrone, respectively) into the fetal brain (124–128 d gestation) in vivo. Both forms of estrogen were concentrated in fetal brain, with the uptake of estrone greater than that of estrone-3-sulfate. We conclude that sulfoconjugated estrogens augment fetal HPA axis activity and that they can cross the fetal blood-brain barrier. We propose that in late gestation the large circulating pool of sulfoconjugated estrogen is a biologically important source of active hormone that might play a role in the timing of parturition in sheep.
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Olofsson, Louise E., Andrew A. Pierce, and Allison W. Xu. "Functional requirement of AgRP and NPY neurons in ovarian cycle-dependent regulation of food intake." Proceedings of the National Academy of Sciences 106, no. 37 (September 2, 2009): 15932–37. http://dx.doi.org/10.1073/pnas.0904747106.
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In female mammals including rodents and humans, feeding decreases during the periovulatory period of the ovarian cycle, which coincides with a surge in circulating estrogen levels. Ovariectomy increases food intake, which can be normalized by estrogen treatment at a dose and frequency mimicking those during the estrous cycle. Furthermore, administration of estrogen to rodents potently inhibits food intake. Despite these well-known effects of estrogen, neuronal subtypes that mediate estrogen's anorexigenic effects have not been identified. In this study, we show that changes in hypothalamic expression of agouti-related protein (Agrp) and neuropeptide Y (Npy) coincide with the cyclic changes in feeding across the estrous cycle. These cyclic changes in feeding are abolished in mice with degenerated AgRP neurons even though these mice cycle normally. Central administration of 17β-estradiol (E2) decreases food intake in controls but not in mice lacking the AgRP neurons. Furthermore, E2 treatment suppresses fasting-induced c-Fos activation in AgRP and NPY neurons and blunts the refeeding response. Surprisingly, although estrogen receptor alpha (ERα) is the key mediator of estrogen's anorexigenic effects, we find that expression of ERα is completely excluded from AgRP and NPY neurons in the mouse hypothalamus, suggesting that estrogen may regulate these neurons indirectly via presynaptic neurons that express ERα. This study indicates that neurons coexpressing AgRP and NPY are functionally required for the cyclic changes in feeding across estrous cycle and that AgRP and NPY neurons are essential mediators of estrogen's anorexigenic function.
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Urabe, Mamoru, Takara Yamamoto, Jo Kitawaki, Hideo Honjo, and Hiroji Okada. "Estrogen biosynthesis in human uterine adenomyosis." Acta Endocrinologica 121, no. 2 (August 1989): 259–64. http://dx.doi.org/10.1530/acta.0.1210259.
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Abstract. Estrogen biosynthesis (aromatase activity) was investigated in human adenomyosis tissue and compared with that of the normal myometrium, endometrium, and endometrial cancer tissues. Homogenates were incubated with [1,2,6,7-3H]androstenedione and NADPH at 37° C for 1 h. After stopping the enzymatic reaction with ethyl acetate, [4-14C]estrone and [4-14C]estradiol-17β were added to the incubated sample. Estrone and estradiol were purified and identified by Bio-Rad AG1-X2 column chromatography, thin-layer chromatography and co-crystallization. Estrogen formed in the incubated sample was calculated from the 3H/14C ratio of the final crystal. The value for estrone formed from androstenedione was 52–132 fmol· h −1 · g−1 wet weight. Aromatase activity in the adenomyosis tissues was higher than that in normal endometrial or myometrial tissues, but lower than that found in myometrial or endometrial tumour tissue. Furthermore, we investigated the effect of danazol, progesterone, and medroxyprogesterone acetate on adenomyosis cells in primary cultures. Aromatase activity in adenomyosis was blocked by danazol, but stimulated by progesterone and MPA. These results indicate that aromatase activity in adenomyosis may contribute to the growth of the ectopic endometrial tissue which occurs in this disease.
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Järvensivu, Päivi, Taija Heinosalo, Janne Hakkarainen, Pauliina Kronqvist, Niina Saarinen, and Matti Poutanen. "HSD17B1 expression induces inflammation-aided rupture of mammary gland myoepithelium." Endocrine-Related Cancer 25, no. 4 (April 2018): 393–406. http://dx.doi.org/10.1530/erc-17-0476.
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Hydroxysteroid (17-beta) dehydrogenase type 1 (HSD17B1) converts low-active estrogen estrone to highly active estradiol. Estradiol is necessary for normal postpubertal mammary gland development; however, elevated estradiol levels increase mammary tumorigenesis. To investigate the significance of the human HSD17B1 enzyme in the mammary gland, transgenic mice universally overexpressing human HSD17B1 were used (HSD17B1TG mice). Mammary glands obtained from HSD17B1TG females at different ages were investigated for morphology and histology, and HSD17B1 activity and estrogen receptor activation in mammary gland tissue were assessed. To study the significance of HSD17B1 enzyme expression locally in mammary gland tissue, HSD17B1-expressing mammary epithelium was transplanted into cleared mammary fat pads of wild-type females, and the effects on mammary gland estradiol production, epithelial cells and the myoepithelium were investigated. HSD17B1TG females showed increased estrone to estradiol conversion and estrogen-response element-driven estrogen receptor signaling in mammary gland tissue, and they showed extensive lobuloalveolar development that was further enhanced by age along with an increase in serum prolactin concentrations. At old age, HSD17B1TG females developed mammary cancers. Mammary-restricted HSD17B1 expression induced lesions at the sites of ducts and alveoli, accompanied by peri- and intraductal inflammation and disruption of the myoepithelial cell layer. The lesions were shown to be estrogen dependent, as treatment with an antiestrogen, ICI 182,780, starting when lesions were already established reversed the phenotype. These data elucidate the ability of human HSD17B1 to enhance estrogen action in the mammary glandin vivoand indicate that HSD17B1 is a factor inducing phenotypic alterations associated with mammary tumorigenesis.
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Baracat, E., M. Haidar, F. J. López, J. Pickar, M. Dey, and A. Negro-Vilar. "Estrogen Activity and Novel Tissue Selectivity ofΔ 8,9-Dehydroestrone Sulfate in Postmenopausal Women." Journal of Clinical Endocrinology & Metabolism 84, no. 6 (June 1, 1999): 2020–27. http://dx.doi.org/10.1210/jcem.84.6.5800.
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Recent basic and clinical advances have consolidated the concept of tissue-selective estrogens, i.e. molecules that express different degrees of partial agonist, full agonist or antagonist activity in different tissues or cells.Δ 8,9-Dehydroestrone sulfate (Δ8,9-DHES) is a conjugated estrogen and a component of conjugated equine estrogens (CEE). It is metabolized in the human in at least a 1:1 ratio to its 17β form, 17β-Δ8,9-DHES. To evaluate its activity in different clinical and biochemical parameters, a clinical research study was conducted with Δ8,9-DHES and estrone sulfate as a comparator in postmenopausal women. Δ8,9-DHES was given orally at a daily dose of 0.125 mg for 12 weeks in a group of 10 women. Two additional groups of women received either estrone sulfate alone (1.25 mg/day) or the combination of Δ8,9-DHES and estrone sulfate at the previously specified doses. A significant and consistent suppression of hot flushes (number, severity, and total score) was observed with Δ8,9-DHES, reaching more than 95% suppression in all parameters of vasomotor symptoms. This level of activity was equal to that obtained with the much higher dose of estrone sulfate, and it was sustained for the duration of the treatment period (12 weeks). Measurements of a bone resorption marker, i.e. urinary excretion of N-telopeptide, demonstrated that Δ8,9-DHES at 8 weeks produced a degree of suppression (40%) similar to that observed with the higher dose of estrone sulfate. Gonadotropin secretion (FSH and LH) was significantly suppressed in women receiving Δ8,9-DHES, similar to that observed with estrone sulfate alone or with the combination of the two. Other parameters, such as total cholesterol, low density lipoprotein cholesterol and high density lipoprotein cholesterol were not modified significantly, whereas serum globulins (sex hormone-binding globulin and corticosteroid-binding globulin) showed only marginal increases after Δ8,9-DHES administration. Taken together with preclinical data, it is found thatΔ 8,9-DHES is an active estrogen with a distinct pharmacological profile that results in significant clinical activity in vasomotor, neuroendocrine (gonadotropin and PRL) and bone preservation parameters, whereas displaying little or no efficacy, at the dose tested, on other peripheral parameters normally affected by estrogens. Collectively, this information supports the concept thatΔ 8,9-DHES is an integral component of CEE, with distinct tissue selectivity contributing to the CEE’s overall clinical activity, and places this estrogen as a distinct member of a novel class of centrally active molecules with unique peripheral tissue selectivity.
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Langer, Peter, Stefan Jopp, Peter Ehlers, Eva Frank, Erzsébet Mernyák, Gyula Schneider, János Wölfling, and Alexander Villinger. "Site-Selective Synthesis of 3,17-Diaryl-1,3,5,16-estratetraenes." Synlett 30, no. 05 (February 7, 2019): 600–604. http://dx.doi.org/10.1055/s-0037-1611720.
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A straightforward, site-selective arylation of the bis(triflate) of estrone by Suzuki–Miyaura reactions has been developed. Monoarylation occurs selectively at the D-ring with good to excellent yield. Such products were exemplarily employed for the synthesis of estrones containing two different aryl substituents.
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Moon, Sohyeon, Ok-Hee Lee, Sujin Lee, Jihyun Lee, Haeun Park, Miseon Park, Eun Mi Chang, Keun-Hong Park, and Youngsok Choi. "STK3/4 Expression Is Regulated in Uterine Endometrial Cells during the Estrous Cycle." Cells 8, no. 12 (December 15, 2019): 1643. http://dx.doi.org/10.3390/cells8121643.
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The uterus is dynamically regulated in response to various signaling triggered by hormones during the estrous cycle. The Hippo signaling pathway is known as an important signaling for regulating cellular processes during development by balancing between cell growth and apoptosis. Serine/threonine protein kinase 3/4 (STK3/4) is a key component of the Hippo signaling network. However, the regulation of STK3/4-Hippo signaling in the uterus is little known. In this study, we investigated the regulation and expression of STK3/4 in the uterine endometrium during the estrous cycle. STK3/4 expression was dynamically regulated in the uterus during the estrous cycle. STK3/4 protein expression was gradually increased from the diestrus stage and reached the highest in the estrus stage. STK3/4 was exclusively localized in the luminal and glandular epithelial cells of the uterus, and phosphorylated STK3/4 was also increased at the estrus stage. Moreover, the increase of STK3/4 expression in uteri was induced by administration of estradiol, but not by progesterone injection in ovariectomized mice. Pretreatment with an estrogen receptor antagonist ICI 182,780 reduced estrogen-induced STK3/4 expression and its phosphorylation. The estrogen-induced STK3/4 expression was related to the increase in phosphorylation of downstream targets including LATS1/2 and YAP. These findings suggest that STK3/4-Hippo signaling acts a novel signaling pathway in the uterine epithelium and STK3/4-Hippo is one of key molecules for connecting between the estrogen downstream signaling pathway and the Hippo signaling pathway leading to regulate dynamic uterine epithelium during the estrous cycle.
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Vaskivuo, Tommi E., Minna Mäentausta, Svea Törn, Olayiwola Oduwole, Annika Lönnberg, Riitta Herva, Veli Isomaa, and Juha S. Tapanainen. "Estrogen Receptors and Estrogen-Metabolizing Enzymes in Human Ovaries during Fetal Development." Journal of Clinical Endocrinology & Metabolism 90, no. 6 (June 1, 2005): 3752–56. http://dx.doi.org/10.1210/jc.2004-1818.
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Estrogen action plays a crucial role in many processes throughout the human life span, including development. Estrogens are pivotal in the regulation of female reproduction, but little is known about their role during ovarian development. To better understand estrogen action during ovarian development, the expression of estrogen receptors (ERs)-α and -β and key enzymes regulating estradiol production, 17β-hydroxysteroid dehydrogenases (17HSDs) types 1, 2, and 7, were analyzed in human fetal ovaries. The expression of ERs was related to the development of ovarian follicles. Before the 26th week of fetal life ERα was only occasionally detected, but from then onward, its expression was detected in ovarian follicles. Consistent expression of ERβ was seen from the 20th week until term. Both ERα and ERβ were localized to the granulosa cells and oocytes. Expression of 17HSD1 and 17HSD7 enzymes, catalyzing the conversion of estrone to more active estradiol, was detected as early as at the 17th week of fetal life. The expression of 17HSD1 displayed a pattern similar to that of ERs and increased toward term, whereas that of 17HSD7 decreased and was negative by the 36th week. 17HSD1 was localized to the granulosa cells, whereas 17HSD7 expression was more diffuse and was found in both granulosa and stromal cells. 17HSD2, converting estradiol to less potent estrone, was negative in all samples studied. The simultaneous appearance of estrogen-converting enzymes and ERs at the time of follicle formation indicates that the machinery for estrogen action exists in fetal ovaries and suggests a possible role for estrogens in the developing ovary.
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Widyaningrum, Yeni, Aulanni’am Aulanni’am, and Agung Pramana Warih Marhendra. "Detection of Reproductive Status in Ongole Crossbred (PO) Cow Based On Vaginal Epithel Morphology and Profile Hormone." Journal of Experimental Life Sciences 10, no. 1 (June 30, 2020): 24–28. http://dx.doi.org/10.21776/ub.jels.2019.010.01.05.
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Hormonal fluctuations in livestock will affect vaginal cytology good overview on the condition of estrous until pregnancy. The purpose of this study was to determine the physiological condition of Ongole crossbred (PO) cow during estrous and determine pregnancy by the description of vaginal epithelial cells, progesterone, and estrogen hormone profiles. The materials were used 35 cows with physiological status (estrous, 5th pregnancy period, 16th pregnancy period, 22nd pregnancy period, and 60th pregnancy period). Samples of Vaginal smear were stained with Giemsa, then it was observed using a microscope, with 40 times magnification. The progesterone and estrogen were analyzed by the ELISA method. The parameters measured were the percentage of vaginal epithelial cells, such as (parabasal, intermediate, and superficial) started estrous phase until the time of pregnancy in cows (5, 16, 22, and 60 days), hormone concentration, as well as the presence or absence of leukocytes. The result showed the Ongole crossbred cow estrous phase percentage of superficial cells 56.27%±6.49 higher than 26.23%±7.98 intermediate cells, followed by parabasal cells 17.50%±4.74. While in Ongole crossbred that were 5th pregnancy period until the 60th predominantly intermediate cell 80.43%±1.31, then the superficial cells 18.09%±1.30 and 1.48%±0.04 parabasal cells. Progesterone concentration was 63.74±1.07 ng.mL-1 in estrus cows, and steadily increased 93.71±0.94 ng.mL-1 to 149.5±0.71 ng.mL-1 in pregnant cows (5-60 days). The concentration of high estrogen levels were 122.38 ± 0.63 ng.mL-1 in the estrous phase, then decreased 81.54±0.44 ng.mL-1 in the pregnancy phase. In conclusion, the concentration of hormone showed a diagnosis of pregnancy, which done by looking at changes in vaginal epithelial cells at the Ongole crossbred cow, and the cow estrous phase showed greater superficial cells compared by pregnant cows (5-60 days).
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Kaun, Christoph, Gersina Rega, Walter Speidl, Stefan Kastl, Thomas Weiss, Philipp Hohensinner, Wolf Dietrich, et al. "The estrogen metabolite 17β-dihydroequilenin counteracts interleukin-1α induced expression of inflammatory mediators in human endothelial cells in vitro via NF-κB pathway." Thrombosis and Haemostasis 95, no. 01 (2006): 107–16. http://dx.doi.org/10.1160/th05-05-0333.
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SummaryIn most studies showing cardio- and vasculoprotective effects of estrogens, 17β-estradiol was used and little information on possible effects of different estrogen metabolites is yet available. We investigated whether particular estrogen metabolites are effective in counteracting inflammatory activation of human endothelium. Human endothelial cells were incubated with 17α-dihydroequilenin, 17β-dihydroequilenin, δ-8,9-dehydroestrone, estrone and 17β-estradiol and stimulated with interleukin (IL)-1α.The expression of IL-6, IL-8 and monocyte chemoattractant protein-1 (MCP-1) was determined. 17β-dihydroequilenin and 17β-estradiol at a concentration of 1µM reduced IL-1α-induced up regulation of IL-6, IL-8 and MCP-1 close to control levels. When both compounds were used in combination an additive effect was observed. 17α-dihydroequilenin and δ-8,9-dehydroestrone showed a similar anti-inflammatory effect only when used at 10µM whereas estrone had no effect. The effect of 17β-dihydroequilenin on IL-1α-induced production of IL-6, IL-8 and MCP-1 was reversed by the estrogen receptor antagonist ICI 182,780. 17β-dihydroequilenin also inhibited IL-1α-induced translocation of p50 and p65 to the nucleus of the cells. We have identified the estrogen metabolite 17β-dihydroequilenin, as an inhibitor of inflammatory activation of human endothelial cells. Characterization of specific estrogens – as shown in our study – could provide the basis for tailored therapies, which might be able to achieve vasoprotection without adverse side effects.
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Kovács, Krisztián, Barna Vásárhelyi, Katalin Mészáros, Attila Patócs, and Gellért Karvaly. "Az ösztrogénmetabolom biológiai és klinikai jelentősége lokális folyamatokban." Orvosi Hetilap 158, no. 24 (June 2017): 929–37. http://dx.doi.org/10.1556/650.2017.30778.
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Abstract: Considerable knowledge has been gathered on the physiological role of estrogens. However, fairly little information is available on the role of compounds produced in the breakdown process of estrone and estradiol wich may play a role in various diseases associated with estrogen impact. To date, approximately 15 extragonadal estrogen-related compounds have been identified. These metabolites may exert protective, or, instead, pro-inflammatory and/or pro-oncogenic activity in a tissue-specific manner. Systemic and local estrogen metabolite levels are not necesserily correlated, which may promote the diagnostic significance of the locally produced estrogen metabolites in the future. The aim of the present study is a bibliographic review of the extragonadal metabolome in peripheral tissues, and to highlight the role of the peripheral tissue homeostasis of estrogens as well as the non-hormonal biological activity and clinical significance of the estrogen metabolome. Orv Hetil. 2017; 158(24): 929–937.
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Charles, Shelton M., Colleen G. Julian, Enrique Vargas, and Lorna G. Moore. "Higher Estrogen Levels During Pregnancy in Andean Than European Residents of High Altitude Suggest Differences in Aromatase Activity." Journal of Clinical Endocrinology & Metabolism 99, no. 8 (August 1, 2014): 2908–16. http://dx.doi.org/10.1210/jc.2013-4102.
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Context: Uteroplacental hypoxia has been reported to lower estrogen levels in preeclampsia as the result of reduced aromatase activity. Objective: We asked whether the chronic hypoxia of residence at high altitude in the absence of preeclampsia lowered estrogen, whether such effects differed in Andean vs European high-altitude residents, and whether such effects were related to uterine artery diameter or blood flow. Design, Setting, and Participants: Studies at weeks 20 and 36 of pregnancy were conducted in 108 healthy Bolivian low- (400 m, n = 53) or high-altitude (3600 m, n = 55) residents of European (n = 28 low and 26 high altitude) or Andean (n = 25 low and 29 high altitude) ancestry. All groups were similar in age, nonpregnant body mass index, and pregnancy weight gain. Results: High-altitude residence increased circulating progesterone, cortisol, estrone, 17β-estradiol, and estriol levels (all P < .01). High-altitude Andeans vs Europeans at week 36 had higher progesterone, estrone, 17β-estradiol, and estriol levels as well as product to substrate ratios for the reactions catalyzed by aromatase, whereas week 36 cortisol levels were greater in the European than Andean women (all P < .05). Lower cortisol, higher estriol (both P < .01), and trends for higher progesterone and 17β-estradiol levels were associated with greater uterine artery diameters and blood flow at high altitude. Conclusions: Chronic hypoxia does not lower but rather raises estrogen levels in multigenerational Andeans vs shorter-term Europeans, possibly as the result of greater aromatase activity. Because hypoxia alone does not lower estrogen, other attributes of the disease may be responsible for the lower estrogen levels seen previously in preeclamptic women.
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Weniger, J. P., and A. Zeis. "Stimulation of aromatase activity in the fetal rat gonads by cAMP and FSH." Acta Endocrinologica 119, no. 3 (November 1988): 381–85. http://dx.doi.org/10.1530/acta.0.1190381.
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Abstract. The gonads from 17- to 21-day-old fetal rats were cultured in vitro in the presence of [3H]testosterone and in the presence or absence of cAMP or FSH, and estrone and estradiol formed were measured by double isotopic dilution and recrystallization to constant specific activity. Estrogen synthesis by testes was stimulated by both cAMP and FSH as early as at 18 days of gestation. FSH did not enhance aromatase activity in ovaries, although cAMP did. It is remarkable that FSH controls estrogen synthesis in the testis earlier than in the ovary.
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Benedek, Zsolt, Peter Girnt, and Julianna Olah. "The Reactivity of Human and Equine Estrogen Quinones towards Purine Nucleosides." Symmetry 13, no. 9 (September 6, 2021): 1641. http://dx.doi.org/10.3390/sym13091641.
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Conjugated estrogen medicines, which are produced from the urine of pregnant mares for the purpose of menopausal hormone replacement therapy (HRT), contain the sulfate conjugates of estrone, equilin, and equilenin in varying proportions. The latter three steroid sex hormones are highly similar in molecular structure as they only differ in the degree of unsaturation of the sterane ring “B”: the cyclohexene ring in estrone (which is naturally present in both humans and horses) is replaced by more symmetrical cyclohexadiene and benzene rings in the horse-specific (“equine”) hormones equilin and equilenin, respectively. Though the structure of ring “B” has only moderate influence on the estrogenic activity desired in HRT, it might still significantly affect the reactivity in potential carcinogenic pathways. In the present theoretical study, we focus on the interaction of estrogen orthoquinones, formed upon metabolic oxidation of estrogens in breast cells with purine nucleosides. This multistep process results in a purine base loss in the DNA chain (depurination) and the formation of a “depurinating adduct” from the quinone and the base. The point mutations induced in this manner are suggested to manifest in breast cancer development in the long run. We examine six reactions between deoxyadenosine and deoxyguanosine as nucleosides and estrone-3,4-quinone, equilin-3,4-quinone, and equilenin-3,4-quinone as mutagens. We performed DFT calculations to determine the reaction mechanisms and establish a structure–reactivity relationship between the degree of unsaturation of ring “B” and the expected rate of DNA depurination. As quinones might be present in the cytosol in various protonated forms, we introduce the concept of “effective barriers” to account for the different reactivity and different concentrations of quinone derivatives. According to our results, both equine estrogens have the potential to facilitate depurination as the activation barrier of one of the elementary steps (the initial Michael addition in the case of equilenin and the rearomatization step in the case of equilin) significantly decreases compared to that of estrone. We conclude that the appearance of exogenous equine estrogen quinones due to HRT might increase the risk of depurination-induced breast cancer development compared to the exposure to endogenous estrone metabolites. Still, further studies are required to identify the rate-limiting step of depurination under intracellular conditions to reveal whether the decrease in the barriers affects the overall rate of carcinogenesis.
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Geisler, J., H. Helle, D. Ekse, N. K. Duong, D. Evans, and P. E. Lønning. "Letrozole (Femara) causes potent suppression of breast cancer tissue estrogen levels in the neoadjuvant setting." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 10532. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.10532.
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10532 Background: Aromatase inhibitors of the third generation like letrozole, anastrozole and exemestane are known to suppress plasma estrogens by 90–99% in postmenopausal women. However, little is known about their influence on tissue estrogen levels. Methods: We investigated the effect of neoadjuvant treatment with letrozole (2.5 mg o.d.) given for 16 weeks to patients with locally advanced breast cancers on tissue levels of estradiol (E2), estrone (E1) and estrone sulfate (E1S) measured with a previously published, highly sensitive, HPLC-RIA method (J. Steroid. Biochem. Mol. Biol. 72, 259–264, 2000). All patients had either estrogen receptor (ER) and/or progesterone receptor (PGR) positive tumors (at least one of the receptors expressed in > 50% of the tumor cells). Results: Mean tissue levels of E2, E1 and E1S were found to be 475.8, 272.4, and 160.5 fmol/g tissue at baseline (geometric mean values). Following 16 weeks of treatment with letrozole, these levels fell to 11.3, 18.2, and 16.0 fmol/g corresponding to a suppression of tissue levels of E2, E1 and E1S by 97.6%, 90.7%, and 90.1%, respectively. All plasma levels of E2, E1 and E1S were in the normal range expected for postmenopausal women prior to treatment with letrozole. The individual plasma estrogen fractions were found suppressed by 96.6%, 99.1% and 99.5%, respectively, during treatment with letrozole. Conclusions: Treatment with neoadjuvant letrozole 2.5 mg o.d. potently suppressed tissue estrogen levels in postmenopausal breast cancer patients by 90.1 to 97.6%, surpassing the results previously reported for anastrozole in a similar setting (Clin. Cancer Res. 7, 1230–1236, 2001). While a significant superiority of letrozole versus anastrozole concerning total body aromatase inhibition and plasma estrogen suppression has previously been recorded (J. Clin. Oncol. 20 (3), 751–757, 2002), we are now able to extend this observation to tissue estrogen levels as well. Letrozole (2.5 mg o.d.) seems superior to anastrozole 1 mg daily with respect to plasma as well as tissue estrogen suppression, advocating head to head comparison of these compounds in early breast cancer. [Table: see text]
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Stack, Douglas E., Justin Ritonya, Scott Jakopovic, and Brittney Maloley-Lewis. "Regioselective deuterium labeling of estrone and catechol estrogen metabolites." Steroids 92 (December 2014): 32–38. http://dx.doi.org/10.1016/j.steroids.2014.08.018.
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Hidayatik, Nanik, Tuty Laswardy Yusuf, Muhammad Agil, Entang Iskandar, and Dondin Sajuthi. "Validasi Analitik Kit ELISA Komersial untuk Mengukur Metabolit Estrogen dan Progesteron pada Feses Tarsius (Tarsius spectrum)." Acta VETERINARIA Indonesiana 6, no. 1 (October 1, 2018): 1–7. http://dx.doi.org/10.29244/avi.6.1.1-7.
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Penentuan status reproduksi pada satwa liar atau satwa yang ditangkarkan merupakan faktor yang sangat penting dalam manajemen pengembangbiakan satwa. Evaluasi metabolit hormon estrogen dan progesteron secara non-invasive dari sampel feses untuk memonitor fungsi reproduksi telah dilakukan sejak lama pada beberapa spesies mamalia. Validasi asai pada Tarsius belum pernah dilaporkan sehingga validasi asai merupakan hal yang sangat penting sebelum digunakan dalam studi karena metabolit steroid bersifat spesifik spesies. Tujuan penelitian ini adalah melakukan validasi analitik kit enzyme linked immunoassay (ELISA) komersial untuk menganalisis metabolit hormon estrogen dan progesteron pada feses T. spectrum. Uji paralelisme dilakukan pada asai DRG® estradiol (E2), estron (E1), dan progesteron (P4) dengan pengenceran bertingkat (1:2–1:128) ekstrak feses dari beberapa status reproduksi yang berbeda pada Tarsius yang dibandingkan dengan kurva standar dari masing-masing asai. Hasil uji paralelisme terhadap kit DRG® estron menunjukkan hasil yang tidak paralel. Dari uji paralelisme DRG® estradiol dan progesteron, didapatkan hasil kurva sampel dengan standar yang tidak konsisten. Hanya ditemukan satu dari lima kurva sampel yang diuji yang paralel dengan kurva standar asai DRG® estrogen dan progesteron. Berdasarkan hasil tes paralelisme tersebut, kit komersial ELISA DRG® estron, estradiol, dan progesteron tidak dapat digunakan untuk mengukur metabolit estrogen dan progesteron pada feses T. spectrum.