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1.
Climacteric ; 24(2): 139-145, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32880220

RESUMO

The Kronos Early Estrogen Prevention Study (KEEPS) was a randomized, double-blind, placebo-controlled trial designed to determine the effects of hormone treatments (menopausal hormone treatments [MHTs]) on the progression of carotid intima-medial thickness (CIMT) in recently menopausal women. Participants less than 3 years from menopause and without a history of overt cardiovascular disease (CVD), defined as no clinical CVD events and coronary artery calcium < 50 Agatston units, received either oral conjugated equine estrogens (0.45 mg/day) or transdermal 17ß-estradiol (50 µg/day), both with progesterone (200 mg/day for 12 days/month), or placebo pills and patches for 4 years. Although MHT did not decrease the age-related increase in CIMT, KEEPS provided other important insights about MHT effects. Both MHTs versus placebo reduced the severity of menopausal symptoms and maintained bone density, but differed in efficacy regarding mood/anxiety, sleep, sexual function, and deposition of ß-amyloid in the brain. Additionally, genetic variants in enzymes for metabolism and uptake of estrogen affected the efficacy of MHT for some aspects of symptom relief. KEEPS provides important information for use of MHT in clinical practice, including type, dose, and mode of delivery of MHT recently after menopause, and how genetic variants in hormone metabolism may affect MHT efficacy on specific outcomes.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Espessura Intima-Media Carotídea , Terapia de Reposição de Estrogênios/métodos , Estrogênios/administração & dosagem , Progesterona/administração & dosagem , Administração Cutânea , Administração Oral , Vasos Coronários/efeitos dos fármacos , Método Duplo-Cego , Estradiol/administração & dosagem , Estrogênios Conjugados (USP)/administração & dosagem , Feminino , Humanos , Menopausa/efeitos dos fármacos , Pessoa de Meia-Idade , Resultado do Tratamento
3.
Biol Reprod ; 100(2): 390-397, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30304517

RESUMO

Cell fusion is involved in the development of some adult organs, is implicated in the pathogenesis of specific types of cancer, and is known to participate in repair/regeneration processes mediated by bone-marrow-derived cells (BMDCs). Endometriosis is a disease characterized by growth of functional endometrial tissue outside of the uterine cavity. Endometriosis shares some molecular properties with cancer and BMDCs home to endometriosis lesions in a mouse model. Our objective was to determine if cell fusion can occur in endometriosis and establish whether bone-marrow-derived cells participate in cell fusion events in lesions. We employed a Cre-Lox system to identify cell fusion events in a mouse model of endometriosis. Fused cells were detected in endometriotic lesions, albeit at a low frequency (∼1 in 400 cells), localized to the stromal compartment, and displayed restricted proliferation. Using 5-fluorouracil-based nongonadotoxic bone marrow transplantation model, we demonstrate that bone marrow cells represent a principal cell source for fusion events in lesions. Cell fusion progeny uniformly lacked expression of selected markers of hematopoietic, endothelial, and epithelial markers, though they expressed the mesenchymal/stromal markers Sca-1 and CD29. This study is the first to describe the phenomenon of cell fusion in endometriosis and points to a mesenchymal population derived from cell fusion events with limited proliferative activity, properties previously attributed to endometrial stem cells. Their putative role in the pathogenesis of the disease remains to be elucidated.


Assuntos
Fusão Celular , Endometriose/patologia , Animais , Modelos Animais de Doenças , Endométrio/citologia , Feminino , Citometria de Fluxo , Camundongos , Mutação
4.
N Z Vet J ; 67(2): 101-104, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30369301

RESUMO

AIM: To assess the efficacy of toltrazuril against the Eimeria spp. affecting brown kiwi (Apteryx mantelli). METHODS: Droppings were collected from three brown kiwi, aged <6 months old, at a captive rearing facility in the North Island of New Zealand, between 22 February and 20 April 2017, on 14 sampling dates. Only droppings (n=30) that were excreted between 03:00 and 07:00, as determined using video surveillance, were included for analysis, reflecting the peak time for shedding of coccidial oocysts for brown kiwi. Oocysts were quantified in each sample and Eimeria species identified on the basis of oocyst morphology. All samples were collected between 2 and 10 days after the birds had been treated with 25 mg/kg toltrazuril. RESULTS: Eimeria spp. oocysts were identified in 28/30 individual samples and on 14/14 sampling dates. Oocyst counts varied from 0 to 328,080 oocysts per gram (opg), and at least one oocyst count >10,000 opg was measured on 12/14 sampling dates. Three species of Eimeria were observed, with Eimeria apteryxii and E. kiwii most commonly encountered, whereas only one sample contained E. paraurii. CONCLUSIONS AND CLINICAL RELEVANCE: In the three birds monitored at this research site, there was a high abundance of E. apteryxii and E. kiwii oocysts in droppings despite recent administration of toltrazuril. These results suggest that the populations of Eimeria spp. affecting brown kiwi at this location appear to possess an ability to survive exposure to toltrazuril. Toltrazuril is widely used at captive rearing facilities to limit the effects of coccidiosis in juvenile kiwi. If a lack of efficacy is confirmed, it will be necessary to investigate alternative treatment regimens alongside broader environmental management strategies.


Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Paleógnatas , Triazinas/uso terapêutico , Animais , Doenças das Aves/tratamento farmacológico , Coccidiose/tratamento farmacológico , Coccidiostáticos/uso terapêutico
5.
Parasitol Res ; 117(9): 2997-3001, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29948203

RESUMO

Captive rearing of wild brown kiwi (Apteryx mantelli) is widely carried out to assist in the recovery of this declining species. As a consequence, high densities of immunologically naïve kiwi are commonly housed in semi-captive conditions, with the potential to result in substantial morbidity and mortality from coccidiosis caused by multiple species of Eimeria. Previous research has described circadian variation in oocyst shedding across multiple avian host species. The aim of this research was to describe any circadian variation in oocyst shedding in brown kiwi. Droppings were collected from brown kiwi (n = 4) at a single captive rearing facility using video surveillance to determine the time of excretion, and oocyst counts were undertaken. Results show that two of the Eimeria spp. affecting brown kiwi exhibit a peak in oocyst shedding between 03.00 and 07.00 with few or no oocysts shed between 08.00 and midnight. These results are not able to be explained by the current hypotheses theorising the evolutionary forces behind the development of this adaptive trait. Our findings increase the current understanding of the biology of the Eimeria spp. affecting brown kiwi and have important implications for the management of captive-reared kiwi, in particular for the accurate interpretation of faecal oocyst counts.


Assuntos
Doenças das Aves/parasitologia , Ritmo Circadiano/fisiologia , Coccidiose/veterinária , Eimeria/fisiologia , Oocistos/isolamento & purificação , Paleógnatas/parasitologia , Carga Parasitária , Animais , Aves/parasitologia , Coccidiose/parasitologia , Fezes/parasitologia
6.
Oncogene ; 36(17): 2345-2354, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27775072

RESUMO

The molecular mechanisms underlying the antineoplastic properties of metformin, a first-line drug for type 2 diabetes, remain elusive. Here we report that metformin induces genome-wide alterations in DNA methylation by modulating the activity of S-adenosylhomocysteine hydrolase (SAHH). Exposing cancer cells to metformin leads to hypermethylation of tumor-promoting pathway genes and concomitant inhibition of cell proliferation. Metformin acts by upregulating microRNA let-7 through AMPK activation, leading to degradation of H19 long noncoding RNA, which normally binds to and inactivates SAHH. H19 knockdown activates SAHH, enabling DNA methyltransferase 3B to methylate a subset of genes. This metformin-induced H19 repression and alteration of gene methylation are recapitulated in endometrial cancer tissue samples obtained from patients treated with antidiabetic doses of metformin. Our findings unveil a novel mechanism of action for the drug metformin with implications for the molecular basis of epigenetic dysregulation in cancer. This novel mechanism of action also may be occurring in normal cells.


Assuntos
Adenosil-Homocisteinase/metabolismo , Metilação de DNA/efeitos dos fármacos , Genômica , Metformina/farmacologia , RNA Longo não Codificante/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinogênese/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Células MCF-7 , MicroRNAs/genética , Estabilidade de RNA/efeitos dos fármacos , RNA Longo não Codificante/química , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , DNA Metiltransferase 3B
13.
Minerva Ginecol ; 65(2): 199-213, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23598784

RESUMO

Progesterone action normally mediates the balance between anti-inflammatory and proinflammatory processes throughout the female reproductive tract. However, in women with endometriosis, endometrial progesterone resistance, characterized by alterations in progesterone responsive gene and protein expression, is now considered a central element in disease pathophysiology. Recent studies additionally suggest that the peritoneal microenvironment of endometriosis patients exhibits altered physiological characteristics that may further promote inflammation-driven disease development and progression. Within this review, we summarize our current understanding of the pathogenesis of endometriosis with an emphasis on the role that inflammation plays in generating not only the progesterone-resistant eutopic endometrium but also a peritoneal microenvironment that may contribute significantly to disease establishment. Viewing endometriosis from the emerging perspective that a progesterone resistant endometrium and an immunologically compromised peritoneal microenvironment are biologically linked risk factors for disease development provides a novel mechanistic framework to identify new therapeutic targets for appropriate medical management.


Assuntos
Endometriose/complicações , Endometriose/fisiopatologia , Doenças dos Genitais Femininos/complicações , Doenças dos Genitais Femininos/imunologia , Inflamação/complicações , Inflamação/fisiopatologia , Animais , Endometriose/tratamento farmacológico , Endometriose/genética , Endometriose/imunologia , Endométrio/fisiologia , Feminino , Previsões , Doenças dos Genitais Femininos/tratamento farmacológico , Doenças dos Genitais Femininos/genética , Genótipo , Humanos , Progesterona/fisiologia
14.
J Phys Chem A ; 117(16): 3319-31, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23534870

RESUMO

An algorithm is presented for one-dimensional NMR systems that employs nonlinear, non-Fourier methods to convert noisy time-dependent free induction decay (FID) data to a denoised frequency spectrum that gives reliable chemical shifts and coupling constants when the spectrum is Lorentzian. It is formulated in a way that increases frequency sensitivity and resolution and, for nuclei of low natural abundance, potentially avoids enrichment totally or in part. The algorithm should also be of use in analytical chemistry where enrichment is not possible. In effect, the useful limit of detection is significantly lowered. The algorithm uses new "phasing" and "feature stability upon accumulation" methods to reliably separate signal from noise at low signal-to-noise ratios where the Fourier spectrum requires many more transients to be definitive as to what is signal and what is noise. The long-standing problem of "false features" that plagued many prior attempts to employ nonlinear methods is thereby resolved for Lorentzian spectra. Examples are reported, and the limitations of the algorithm are discussed.

16.
J Cardiovasc Transl Res ; 2(3): 228-39, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19668346

RESUMO

Observational and epidemiological studies suggest that menopausal hormone therapy (MHT) reduces cardiovascular disease (CVD) risk. However, results from prospective trials showed neutral or adverse effects most likely due to differences in participant demographics, such as age, timing of initiation of treatment, and preexisting cardiovascular disease, which reflected in part the lack of basic science information on mechanisms of action of hormones on the vasculature at the time clinical trials were designed. The Kronos Early Estrogen Replacement Study (KEEPS) is a prospective, randomized, controlled trial designed, using findings from basic science studies, to test the hypothesis that MHT when initiated early in menopause reduces progression of atherosclerosis. KEEPS participants are younger, healthier, and within 3 years of menopause thus matching more closely demographics of women in prior observational and epidemiological studies than women in the Women's Health Initiative hormone trials. KEEPS will provide information relevant to the critical timing hypothesis for MHT use in reducing risk for CVD.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Estrogênios Conjugados (USP)/administração & dosagem , Progesterona/administração & dosagem , Projetos de Pesquisa , Pesquisa Translacional Biomédica , Saúde da Mulher , Administração Cutânea , Administração Oral , Adulto , Doenças Cardiovasculares/etiologia , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Pulsoterapia , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
17.
Mol Hum Reprod ; 13(5): 323-32, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17350963

RESUMO

Endometriosis is a poorly understood gynaecologic disorder that is associated with infertility. In this study, we examined the expression of HOXA10 in the eutopic endometrium of baboons with induced endometriosis. A decrease in HOXA10 mRNA was observed after 3, 6, 12 and 16 months of disease, which reached statistical significance at 12 and 16 months. HOXA10 protein levels were decreased in both the epithelial and stromal cells of the endometrium. Furthermore, expression of beta3 integrin (ITGB3), which is upregulated by HOXA10, was decreased, whereas EMX2, a gene that is inhibited by HOXA10, was increased. Next, methylation patterns of the HOXA10 gene were analysed in the diseased and control animals. The F1 region on the promoter was found to be the most significantly methylated in the endometriosis animals and this may account for the decrease in HOXA10 expression. Finally, we demonstrate that stromal cells from the eutopic endometrium of baboons with endometriosis expressed significantly higher levels of insulin-like growth factor binding protein-1 (IGFBP1) mRNA than disease-free animals in response to estradiol, medroxyprogesterone acetate and dibutyryl cAMP (H + dbcAMP). The functional role of HOXA10 in IGFBP1 expression was further explored using human endometrial stromal cells (HSC). Overexpression of HOXA10 in HSC resulted in a decrease of IGFBP1 mRNA, whereas silencing HOXA10 caused an increase of IGFBP1 mRNA, even in the presence of H + dbcAMP. These data demonstrate that HOXA10 negatively influences IGFBP1 expression in decidualizing cells. Thus, the decrease in HOXA10 levels may in part be involved with the altered uterine environment associated with endometriosis.


Assuntos
Decídua/metabolismo , Endometriose/metabolismo , Endométrio/metabolismo , Proteínas de Homeodomínio/metabolismo , Animais , Bucladesina/farmacologia , Células Cultivadas , Metilação de DNA , Decídua/crescimento & desenvolvimento , Decídua/patologia , Endometriose/patologia , Endométrio/efeitos dos fármacos , Endométrio/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Proteínas Homeobox A10 , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Acetato de Medroxiprogesterona/farmacologia , Papio , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Fatores de Transcrição/metabolismo
18.
J Chem Phys ; 120(9): 4194-206, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15268586

RESUMO

We extract the dynamics implicit in an algebraic fitted model Hamiltonian for the deuterium chromophore's vibrational motion in the molecule CDBrClF. The original model has four degrees of freedom, three positions and one representing interbond couplings. A conserved polyad allows in a semiclassical approach the reduction to three degrees of freedom. For most quantum states we can identify the underlying motion that when quantized gives the said state. Most of the classifications, identifications, and assignments are done by visual inspection of the already available wave function semiclassically transformed from the number representation to a representation on the reduced dimension toroidal configuration space corresponding to the classical action and angle variables. The concentration of the wave function density to lower dimensional subsets centered on idealized simple lower dimensional organizing structures and the behavior of the phase along such organizing centers already reveals the atomic motion. Extremely little computational work is needed.

19.
Hum Gene Ther ; 12(17): 2121-7, 2001 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11747601

RESUMO

Although gene therapy has been used for correction of metabolic defects in diseases such as cystic fibrosis, as adjuvant treatment in cancer, and in the treatment of infectious diseases, there has been no report of gene transfer to the intact female reproductive tract. We assessed the ability to transfect the human uterus ex vivo and thereby evaluate the applicability of gene therapy to gynecology. The uterine lumen was accessed transcervically, using an intrauterine insemination catheter. pcDNA3.1 plasmid containing the Escherichia coli lacZ reporter gene was delivered to each uterus via liposome-mediated transfection. Control uteri were transfected with empty pcDNA3.1. Immunohistochemical analysis revealed beta-galactosidase expression in the lacZ-treated uteri in endometrial epithelial cells, endometrial stromal cells, and myometrium to a depth of 1.75 cm from the endometrial-myometrial junction. Highest expression was seen in endometrial glandular epithelial cells, with significant expression in the stroma and adjacent myometrium. Each of these cell types in the control uteri showed no beta-galactosidase expression. Successful gene transfection and expression in the intact human uterus can be accomplished easily, rapidly, and efficiently. Gene therapy may have wide applicability in the treatment and study of gynecologic disease.


Assuntos
Terapia Genética/métodos , Lipossomos/administração & dosagem , Transfecção/métodos , Transgenes/genética , Útero/metabolismo , Adulto , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Óperon Lac/genética , Lipossomos/efeitos adversos , Reprodutibilidade dos Testes , Doenças Uterinas/genética , Doenças Uterinas/terapia , Útero/citologia , Útero/patologia , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
20.
Dev Dyn ; 222(3): 538-44, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11747087

RESUMO

Hoxa10 is a homeobox gene that is expressed both during the embryogenesis of the genitourinary tract and in the adult reproductive tract. Maternal Hoxa10 expression is necessary for endometrial receptivity to blastocyst implantation. The mechanism by which Hoxa10 induces endometrial development to a state of receptivity is unknown as HOXA10-deficient endometrium appears histologically normal. We altered the expression of Hoxa10 in the uterus of cycling adult female mice and examined the uterus at the time of implantation by transmission electron microscopy for alterations in epithelial morphology. Pinopods are projections on the surface of the uterine endometrial epithelial cells that develop transiently at the time of endometrial receptivity. Blocking Hoxa10 expression by transfection of Hoxa10 antisense into the cycling mouse uterus before implantation dramatically decreased pinopod number. Constitutively expressing Hoxa10 in the uterus just before the normal time of pinopod formation resulted in increased pinopod number. Therefore, Hoxa10 is necessary for pinopod development. Hox genes have been implicated in both the regulation of cellular proliferation and the determination of developmental fate. Hoxa10 exemplifies this dual role in the uterus by regulating both endometrial stromal cell proliferation and epithelial cell morphogenesis. Taken together, these results demonstrate that maternal Hoxa10 has an essential role in pinopod development and this function of Hoxa10 likely contributes to endometrial receptivity for the purpose of blastocyst implantation.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Implantação do Embrião/fisiologia , Proteínas de Homeodomínio , Prenhez/metabolismo , Útero/fisiologia , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/farmacologia , Endométrio/citologia , Endométrio/efeitos dos fármacos , Endométrio/fisiologia , Endométrio/ultraestrutura , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Feminino , Proteínas Homeobox A10 , Camundongos/embriologia , Microscopia Eletrônica , Oligonucleotídeos Antissenso/farmacologia , Gravidez , Útero/citologia , Útero/efeitos dos fármacos
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