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1.
Phys Rev Lett ; 133(6): 066501, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39178448

RESUMO

A supposedly nonmagnetic 5d^{1} double perovskite oxide is investigated by a combination of spectroscopic and theoretical methods, namely, resonant inelastic x-ray scattering, x-ray absorption spectroscopy, magnetic circular dichroism, and multiplet ligand-field calculations. We found that the large spin-orbit coupling admixes the 5d t_{2g} and e_{g} orbitals, covalency raises the 5d population well above the nominal value, and the local symmetry is lower than O_{h}. The obtained electronic interactions account for the finite magnetic moment of Os in this compound and, in general, of 5d^{1} ions. Our results provide direct evidence of elusive Jahn-Teller distortions, hinting at a strong electron-lattice coupling.

2.
Reprod Biomed Online ; 30(2): 166-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25498593

RESUMO

The new classification system of uterine anomalies from the European Society of Human Reproduction and Embryology and the European Society for Gynaecological Endoscopy defines T-shaped and tubular-shaped infantilis uteri as 'dysmorphic'. Such malformations have been proven to be associated with poor reproductive performance. A prospective observational study was conducted with 30 infertile women with dysmorphic uterus who underwent the novel Hysteroscopic Outpatient Metroplasty to Expand Dysmorphic Uteri (HOME-DU ) technique. Incisions are made on the uterine walls with a 5 Fr bipolar electrode. The procedure was conducted in outpatients under conscious sedation, using a 5-mm office hysteroscope. The technique was successful in all cases without complications. A net increase of uterine volume was found, as measured at hysteroscopy and three-dimensional transvaginal ultrasound (P < 0.001). Uterine morphology improved in all patients but one. At mean follow-up of 15 months, clinical pregnancy rate was 57% and term delivery rate 65%. These early data support HOME-DU as safe and effective in expanding the volume and normalizing the appearance of the uterine cavity of dysmorphic uteri. Although the cohort was small, pregnancy and live births outcomes were favourable in this poor-prognosis group, implying desirable benefits, which should be compared with other techniques.


Assuntos
Histeroscopia , Infertilidade Feminina/cirurgia , Anormalidades Urogenitais/cirurgia , Útero/anormalidades , Adulto , Procedimentos Cirúrgicos Ambulatórios , Feminino , Humanos , Infertilidade Feminina/terapia , Pacientes Ambulatoriais , Projetos Piloto , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia , Útero/anatomia & histologia , Útero/cirurgia , Vagina/diagnóstico por imagem
3.
G Chir ; 33(4): 139-46, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22668535

RESUMO

The incidence and mortality of cervical cancer have changed over the past 50 years in developed countries, but this kind of tumor still remains a significant clinical problem because it is the second most common cause of morbidity and mortality from cancer among women. After histological confirmation of invasive cervical cancer, the extent of disease was determined using clinical criteria to assign a stage. This assessment is important because, while for the other gynecologic cancers clinical information obtained by surgery and histopathological examination is implemented and concurs to define the staging of the disease, the cervical cancer tumor stage is given after the primary diagnosis. In this review we discuss how the surgical approach to cervical cancer has been evolved, in order to modulate the radicality of the intervention itself and thus to preserve the pelvic innervation. This step has been achieved by deepening knowledge of functional pelvic anatomy and modulating the radicality of hysterectomy according to well defined surgical landmarks.


Assuntos
Histerectomia/métodos , Neoplasias do Colo do Útero/cirurgia , Feminino , Humanos , Histerectomia/classificação , Pelve/inervação
4.
Climacteric ; 13(2): 141-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20082603

RESUMO

OBJECTIVE: The pathogenesis of hot flushes involves several brain neurotransmitter systems, and changes in serotonin turnover have been hypothesized. Veralipride is an anti-dopaminergic agent that relieves hot flushes and putatively also modulates serotonergic neurons. To further elucidate this relationship, in the present study we evaluated whether administration of veralipride for relief of hot flushes is able to affect serum levels of the serotonin precursor tryptophan in postmenopausal women. METHODS: Twenty-four postmenopausal women were randomly assigned to receive veralipride (100 mg/day) or similar placebo tablets for 3 months (n = 12 per group). Free tryptophan and total tryptophan (free + protein-bound) levels were assayed before and monthly by high pressure liquid chromatography. Data were analyzed with repeated measures ANOVA and Student-Newman-Keuls post hoc test. RESULTS: Relief of hot-flushes was achieved with complete suppression of symptoms after veralipride, but not placebo, treatment. In the veralipride group, total tryptophan levels significantly (p < 0.05) decreased from baseline (11.2 +/- 0.4 microg/ml) to 3 months (8.0 +/- 0.3 microg/ml), as well as free tryptophan concentrations (baseline 2.1 +/- 0.1 microg/ml; after 3 months 1.3 +/- 0.1 microg/ml; p < 0.05). No changes were recorded in the placebo group. CONCLUSION: Women treated with veralipride for relief of menopausal symptoms show a decrease in serum levels of serotonin precursors, suggesting that the brain serotonergic system may be involved in the pathogenesis of postmenopausal vasomotor symptoms.


Assuntos
Fogachos/sangue , Fogachos/tratamento farmacológico , Menopausa/sangue , Serotonina/sangue , Sulpirida/análogos & derivados , Análise de Variância , Cromatografia Líquida de Alta Pressão , Antagonistas de Dopamina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Sulpirida/uso terapêutico , Triptofano/sangue
5.
Hum Reprod ; 24(10): 2600-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19549703

RESUMO

BACKGROUND: Follistatin is an activin-binding protein produced by several tissues, including endometrium and endometriotic implants. We aimed to quantify follistatin in patients with ovarian endometriosis and investigate its value as a diagnostic marker. METHODS: Women undergoing laparoscopic excision of ovarian endometrioma (n = 52) or other benign ovarian cysts (n = 52) were studied, plus women with non-ovarian endometriosis (n = 11) and healthy controls (n = 27). Serum was collected from all subjects, and peritoneal and cystic fluid from a subset with endometrioma. Follistatin was measured by enzyme-linked immunosorbent assay. The diagnostic accuracy of follistatin to detect endometrioma was evaluated by receiver operating characteristic (ROC) curve and compared with cancer antigen (CA)-125. RESULTS: Serum follistatin was increased in women with ovarian endometrioma (2080 +/- 94 pg/ml) compared with controls (545 +/- 49 pg/ml, P < 0.001), other benign ovarian cysts (795 +/- 60 pg/ml, P < 0.001) or non-ovarian endometriosis (1271 +/- 115 pg/ml, P < 0.001). Cystic fluid showed a higher concentration of follistatin (9850 +/- 4461 pg/ml) than peritoneal fluid (1885 +/- 261 pg/ml, P < 0.001) and serum (P < 0.001). Follistatin levels detected 48/52 cases of endometrioma (92% sensitivity) at 1433 pg/ml cut-off, corresponding to 92% specificity. CA-125 detected only 44% of endometriomas with 90% specificity. ROC curve comparison showed follistatin was more accurate than CA-125 to discriminate women with endometrioma either from controls or women with other benign ovarian cysts (P < 0.0001). CONCLUSIONS: Serum follistatin is increased in women with endometriosis and allows clear distinction between endometrioma and other benign ovarian cysts. Follistatin has the sensitivity and specificity to become a useful clinical marker of ovarian endometrioma.


Assuntos
Endometriose/sangue , Folistatina/sangue , Doenças Ovarianas/sangue , Adulto , Biomarcadores , Antígeno Ca-125/sangue , Diagnóstico Diferencial , Endometriose/diagnóstico , Feminino , Humanos , Doenças Ovarianas/diagnóstico
6.
Ultrasound Obstet Gynecol ; 32(2): 205-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18663768

RESUMO

OBJECTIVE: To evaluate whether measurement of the thickness of the fetal membranes by high-resolution ultrasound is a useful marker to predict preterm delivery. METHODS: One hundred and fifty-eight women with singleton pregnancies at 18-35 gestational weeks were enrolled consecutively at our referral center for obstetric care and the thickness of their fetal membranes was measured using high-resolution ultrasound equipment. Data were analyzed to determine whether there were significant differences between those delivering at term and those delivering preterm. Receiver-operating characteristics (ROC) curves were used to determine the best cut-off point of membrane thickness for predicting preterm birth. RESULTS: Women who delivered preterm had greater fetal membrane thickness than did those who delivered at term (1.67 +/- 0.27 mm vs. 1.14 +/- 0.30 mm, P < 0.0001). For the best cut-off indicated by ROC curve analysis (1.2 mm), the sensitivity and specificity for predicting preterm birth were 100% (95% CI, 80.3-100) and 69.5% (95% CI, 61.2-77.0), respectively, and positive and negative likelihood ratios were 3.3 and 0.0, respectively. CONCLUSION: Sonographic measurement of fetal membrane thickness could be helpful in the prediction of preterm delivery.


Assuntos
Membranas Extraembrionárias/diagnóstico por imagem , Nascimento Prematuro/diagnóstico , Ultrassonografia Pré-Natal/métodos , Adulto , Membranas Extraembrionárias/fisiologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Nascimento Prematuro/prevenção & controle , Curva ROC , Adulto Jovem
7.
Placenta ; 28(10): 1020-3, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17561251

RESUMO

INTRODUCTION: Neurokinin B (NKB) is a neuropeptide belonging to the family of tachykinins-related peptides that elicits contractility of human myometrial strips in vitro. The present study evaluates whether placental mRNA and peptide expression of NKB change in women at preterm labor. METHODS: A group of 26 women with singleton pregnancies were enrolled in the study. Placental tissue specimens were collected from pregnant women delivering after elective cesarean section, after labor at term, or after preterm labor. Changes in placental NKB mRNA and protein expression were evaluated by real-time quantitative RT-PCR analysis and by immunofluorescence respectively. RESULTS: Placental mRNA expression of NKB was significantly higher after term and preterm labor (P<0.001) than cesarean section, and highest after preterm labor. Immunofluorescent staining in placentas from preterm or term labor was more intense than after cesarean section (P<0.001). In particular, NKB protein expression was higher in placentas collected after preterm labor than those collected after term labor. DISCUSSION: Neurokinin B mRNA and protein are highly expressed in placenta at term and preterm labor; thus, the involvement of this neuropeptide in the events cascade leading to parturition may be suggested.


Assuntos
Trabalho de Parto/fisiologia , Neurocinina B/genética , Trabalho de Parto Prematuro/fisiopatologia , Placenta/fisiopatologia , Estudos Transversais , Feminino , Humanos , Neurocinina B/biossíntese , Gravidez , RNA Mensageiro/metabolismo
8.
Eur J Endocrinol ; 157(3): 279-84, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17766709

RESUMO

OBJECTIVE: Placental corticotropin-releasing factor (CRF) affects myometrial contractility and the secretion of several uterotonins such as prostaglandins (PGs); however, the activity of CRF is counteracted by CRF-binding protein (CRF-BP). At term and pre-term labor, CRF levels in maternal plasma are highest whereas those of CRF-BP are falling, and the cause of this fall is unknown. Thus, in this study, we investigated the effect of PG administration for labor induction on maternal plasma CRF and CRF-BP concentrations. DESIGN: Maternal plasma CRF and CRF-BP levels were assayed before and after (2 h later) induction of labor by intracervical administration of prostaglandin E(2) (PGE(2)), and at delivery in a group of healthy post-term pregnancies (n=18). Controls were women at term out of labor (n=22), who subsequently progressed to deliver a healthy singleton baby. METHODS: CRF was measured by two-site immunoradiometric assay, and CRF-BP was assayed by radioimmunoassay. RESULTS: Maternal plasma CRF levels were significantly (P<0.0001) lower and CRF-BP significantly (P<0.0005) higher in post-term than in term pregnancies. With respect to induction of labor, 2 mg PGE(2) were sufficient to increase maternal plasma CRF levels at delivery (P<0.005). While 0.5 mg PGE(2) significantly decreased maternal plasma CRF-BP levels at delivery (P<0.001), 2.0 mg PGE(2) significantly reduced CRF-BP concentrations both after 2 h (P<0.05) and at delivery (P<0.0001). CONCLUSIONS: In the light of the well-known stimulation of prostaglandin release by CRF, these data suggest a positive feedback effect of PGE(2) on maternal CRF release during induced labor.


Assuntos
Proteínas de Transporte/sangue , Hormônio Liberador da Corticotropina/sangue , Dinoprostona/administração & dosagem , Trabalho de Parto Induzido/métodos , Ocitócicos/administração & dosagem , Gravidez Prolongada/sangue , Adulto , Dinoprostona/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Feminino , Humanos , Recém-Nascido , Ocitócicos/metabolismo , Parto/sangue , Parto/efeitos dos fármacos , Gravidez , Contração Uterina/efeitos dos fármacos , Contração Uterina/metabolismo
9.
Eur J Obstet Gynecol Reprod Biol ; 133(2): 164-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17046145

RESUMO

OBJECTIVE: This study was designed to evaluate whether the detection of serum antiphospholipid autoantibodies may be useful in predicting pregnancy outcome in women with threatened abortion in the first trimester. STUDY DESIGN: A group of 77 pregnant women of between 8 and 12 weeks' gestation with vaginal bleeding was tested for serum antiphospholipid, lupus anticoagulants, anticardiolipin, antinuclear antibodies, and anti-beta2-glycoprotein I antibodies, and was followed up until the spontaneous end of pregnancy. A control group composed of 15 healthy women with uncomplicated gestation was tested contemporarily for the same antibody panel. RESULTS: Of the 77 patients with threatened abortion, 32 (41.5%) progressed to deliver at term and 45 (58.5%) experienced early pregnancy loss. Among the antibodies evaluated, only anti-beta2-glycoprotein I was significantly more frequent in those women whose pregnancy resulted in spontaneous abortion (22/45, 49%) than in those who progressed to term (6/32, 19%) or in the control group (2/15, 13%; p=0.004). This difference was specific to the IgM isotype (p=0.001). After adjustment by multivariate analysis, the odds ratio for pregnancy loss associated with a positive beta2-glycoprotein I antibody test was 5.18 (p=0.001). CONCLUSION: The detection of anti-beta2-glycoprotein I antibodies is associated with an increased risk of pregnancy loss in women with threatened abortion in the first trimester.


Assuntos
Aborto Espontâneo/epidemiologia , Ameaça de Aborto/imunologia , Autoanticorpos/sangue , Primeiro Trimestre da Gravidez/imunologia , beta 2-Glicoproteína I/imunologia , Ameaça de Aborto/diagnóstico , Adulto , Estudos de Coortes , Feminino , Humanos , Gravidez , Prognóstico , Risco
10.
Placenta ; 27(4-5): 432-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16051348

RESUMO

The aims of the present study were to evaluate the umbilical cord serum activin A concentrations in complicated pregnancies and also to explore the relationship between activin A levels and blood flow velocity in fetal arteries. Umbilical cord blood samples were obtained postpartum after a full term uneventful gestation (control group, n=40), and from pregnancies complicated by gestational diabetes (n=13), preterm labour (n=18), or pre-eclampsia (n=19). Cord serum activin A levels were three-fold higher in pregnancies complicated by pre-eclampsia (1.17+/-0.14 ng/ml, p<0.01) than in the control group (0.43+/-0.03 ng/ml), but were unaltered in the diabetes and preterm labour groups. The pre-eclampsia group had a marked increase of umbilical artery pulsatility index (PI) and also a decrease of middle cerebral artery PI (p<0.01). Furthermore, activin A concentration correlated directly with the umbilical artery PI (r=0.540, p=0.021), with the length of stay in the Neonatal Intensive Care Unit (r=0.857, p<0.001) and also with cord blood pH (r=-0.886, p<0.001). In conclusion, umbilical cord serum activin A levels are increased in the presence of pre-eclampsia and provide an indirect marker of impaired blood flow in the uteroplacental and fetal circulation.


Assuntos
Ativinas/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Sangue Fetal/metabolismo , Subunidades beta de Inibinas/sangue , Circulação Placentária/fisiologia , Pré-Eclâmpsia/sangue , Adulto , Estudos Transversais , Diabetes Gestacional/sangue , Diabetes Gestacional/fisiopatologia , Feminino , Humanos , Recém-Nascido , Artéria Cerebral Média/fisiopatologia , Trabalho de Parto Prematuro/sangue , Trabalho de Parto Prematuro/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Artérias Umbilicais/fisiopatologia
11.
J Clin Endocrinol Metab ; 90(4): 2378-83, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15623814

RESUMO

The present study evaluated vasoactive intestinal peptide (VIP) and substance P (SP) mRNA expressions and the localization of both peptides in first- and third-trimester human placentas. VIP and SP mRNAs were detected by slot blot analysis in first- and third-trimester placental tissues. By immunohistochemistry both neuropeptides were localized in the trophoblast (syncytium and cytotrophoblastic cells) of the chorionic villi. Because little information is available on the role of VIP and/or SP on the secretion of placental hormones, we investigated the effect of these neuropeptides on human chorionic gonadotropin (hCG) and progesterone release from primary cultured human trophoblastic and JEG-3 cells. The addition of increasing doses of VIP resulted in a dose-dependent stimulation of hCG release from cultured human trophoblast and JEG-3 cells. Increasing doses of VIP also dose-dependently stimulated progesterone secretion from primary cultured trophoblastic cells at all time points evaluated and from JEG-3 cells only after 3 h. SP did not affect hCG and progesterone secretion either in cultured human trophoblast or in JEG-3 cells. In conclusion, the present study demonstrates that VIP and SP are mainly expressed in human trophoblasts, and that VIP modulates the in vitro secretion of hCG and progesterone, suggesting a different role in trophoblastic function of the two peptides.


Assuntos
Gonadotropina Coriônica/metabolismo , Placenta/metabolismo , Progesterona/metabolismo , Substância P/análise , Peptídeo Intestinal Vasoativo/análise , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Gravidez , Precursores de Proteínas/análise , Precursores de Proteínas/genética , Substância P/genética , Substância P/fisiologia , Taquicininas/análise , Taquicininas/genética
12.
J Clin Endocrinol Metab ; 90(9): 5361-5, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15956084

RESUMO

CONTEXT: Placental urocortin has a role in the cascade of events leading to parturition by stimulating myometrial contractility and placental uterotonins secretion. OBJECTIVE: The objective of this study was to evaluate urocortin levels in maternal and fetal [umbilical cord artery (UCA) and vein (UCV)] plasma at term and preterm labor. DESIGN: The study design was a controlled cross-sectional study performed from November 2003 to June 2004. SETTING: This study was performed at the Division of Obstetrics and Gynecology, University of Siena (Siena, Italy). PATIENTS: Plasma samples were collected at term in the absence of labor (TNL; n = 27; 39.3 +/- 0.1 gestational weeks), at term spontaneous vaginal delivery (TL; n = 24; 40.1 +/- 0.2 gestational weeks), and at preterm labor (PTL; n = 19; 32.4 +/- 0.4 gestational weeks). Changes in urocortin mRNA expression were also evaluated in placentas collected from TNL (n = 11), TL (n = 11), and PTL (n = 10). INTERVENTION: Urocortin levels were measured by specific RIA. Changes in placental mRNA expression were determined by real-time quantitative RT-PCR analysis. RESULTS: Maternal and UCA plasma urocortin levels were significantly (P < 0.0001 for all) higher in TL and PTL than in TNL. Furthermore, UCA concentrations were significantly (P < 0.0001 for all) higher than and correlated with maternal concentrations (TNL: r = 0.45; P < 0.05; TL: r = 0.959; P < 0.0001; PTL: r = 0.7719; P < 0.0001). UCV levels were significantly (P < 0.001) higher in TL and PTL than in TNL and were significantly (P < 0.0001 for all) higher than and significantly (P < 0.0001 for all) correlated with maternal values, but were significantly (P < 0.0001 for all) lower than and correlated with UCA values (TNL: r = 0.9548; P < 0.0001; TL: r = 0.927; P < 0.0001; PTL: r = 0.838; P < 0.0001). Placental urocortin mRNA expression did not differ among TNL, TL, and PTL samples. CONCLUSIONS: Fetal urocortin secretion is increased in term and preterm labor. Whether these changes are a consequence rather than a cause of human parturition remains to be addressed.


Assuntos
Hormônio Liberador da Corticotropina/sangue , Sangue Fetal , Trabalho de Parto/sangue , Trabalho de Parto Prematuro/sangue , Hormônio Liberador da Corticotropina/genética , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Concentração Osmolar , Placenta/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Cordão Umbilical , Veias Umbilicais , Urocortinas
13.
Artigo em Inglês | MEDLINE | ID: mdl-25613515

RESUMO

S100B protein has been recently proposed as a consolidated marker of brain damage and death in adult, children and newborn patients. The present study evaluates whether the longitudinal measurement of S100B at different perioperative time-points may be a useful tool to identify the occurrence of perioperative early death in congenital heart disease (CHD) newborns. We conducted a case-control study in 88 CHD infants, without pre-existing neurological disorders or other co-morbidities, of whom 22 were complicated by perioperative death in the first week from surgery. Control group was composed by 66 uncomplicated CHD infants matched for age at surgical procedure. Blood samples were drawn at five predetermined time-points before during and after surgery. In all CHD children, S100B values showed a pattern characterized by a significant increase in protein's concentration from hospital admission up to 24-h after procedure reaching their maximum peak (P<0.01) during cardiopulmonary by-pass and at the end of the surgical procedure. Moreover, S100B concentrations in CHD death group were significantly higher (P<0.01) than controls at all monitoring time-points. The ROC curve analysis showed that S100B measured before surgical procedure was the best predictor of perioperative death, among a series of clinical and laboratory parameters, reaching at a cut-off of 0.1 µg/L a sensitivity of 100% and a specificity of 63.7%. The present data suggest that in CHD infants biochemical monitoring in the perioperative period is becoming possible and S100B can be include among a series of parameters for adverse outcome prediction.

14.
J Clin Endocrinol Metab ; 82(3): 835-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9062492

RESUMO

Corticotropin-releasing factor (CRF)-binding protein (CRF-BP) modulates the activity of the hypothalamus-pituitary-adrenal axis during pregnancy, counteracting the actions of circulating or locally produced CRF. The aim of the present study was to evaluate CRF and CRF-BP levels in amniotic fluid of healthy pregnant women during the last 4 weeks of gestation and during spontaneous labor at term. A cross-sectional study was conducted on amniotic fluid collected from pregnant women (n = 68), subdivided into two groups: 1) not in labor (n = 31), and 2) in labor (n = 37). CRF-BP was measurable in all specimens of amniotic fluid, but at 37 weeks of pregnancy the concentration in amniotic fluid was lower (10-fold) than that in maternal plasma (P < 0.01). Pregnant women at 39 and 40 weeks gestation had amniotic fluid CRF-BP levels significantly lower than those at 37 weeks (P < 0.01), and pregnant in women in labor had significantly lower levels than women at term but not in labor (P < 0.01). CRF levels in amniotic fluid and plasma collected in women at 40 weeks gestation not in labor or in labor were significantly higher than those at 37 weeks (P < 0.01). During the last 4 weeks of gestation, amniotic fluid CRF levels in women not in labor did not significantly differ from those obtained at term labor. During the last weeks of pregnancy, amniotic fluid CRF-BP levels decrease and are inversely correlated to CRF levels. The decrease in amniotic fluid CRF-BP at term, augmenting the amount of free CRF, supports the hypothesis that labor is associated with significant changes in local autocrine and paracrine factors that may affect PG release and myometrial contractility, contributing to the mechanism of parturition.


Assuntos
Líquido Amniótico/metabolismo , Proteínas de Transporte/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Trabalho de Parto , Gravidez/metabolismo , Adulto , Estudos Transversais , Feminino , Humanos , Terceiro Trimestre da Gravidez
15.
J Clin Endocrinol Metab ; 89(9): 4673-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15356079

RESUMO

In the present study we measured maternal plasma concentrations of two placental neurohormones, corticotropin-releasing factor (CRF) and CRF-binding protein (CRF-BP), in 58 at-risk pregnant women consecutively enrolled between 28 and 29 wk of pregnancy to evaluate whether their evaluation may predict third trimester-onset preeclampsia (PE). The statistical significance was assessed by t test. The cut-off points for defining altered CRF and CRF-BP levels for prediction of PE were chosen by receiving operator characteristics curve analysis, and the probability of developing PE was calculated for several combinations of hormone testing results. CRF and CRF-BP levels were significantly (both P < 0.0001) higher and lower, respectively, in the patients (n = 20) who later developed PE than in those who did not present PE at follow-up. CRF at the cut-off 425.95 pmol/liter achieved a sensitivity of 94.8% and a specificity of 96.9%, whereas CRF-BP at the cut-off 125.8 nmol/liter combined a sensitivity of 92.5% and a specificity of 82.5% as single markers for prediction of PE. The probability of PE was 34.5% in the whole study population, 93.75% when both CRF and CRF-BP levels were changed, and 0% if both hormone markers were unaltered. The measurement of CRF and CRF-BP levels may add significant prognostic information for predicting PE in at-risk pregnant women.


Assuntos
Proteínas de Transporte/sangue , Hormônio Liberador da Corticotropina/sangue , Pré-Eclâmpsia/sangue , Adulto , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico , Gravidez , Probabilidade , Estudos Prospectivos
16.
J Clin Endocrinol Metab ; 80(10): 3073-6, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7559899

RESUMO

Human placenta and uterine tissues are sites of production and local action of corticotropin-releasing factor (CRF). The recent evidence that CRF-binding protein (CRF-BP), a protein that blocks CRF-induced pituitary ACTH release, is produced by placental tissues suggested the present study to investigate the effects of CRF-BP on prostaglandin release and contractile activity of myometrial strips. Primary cultures of decidual cells were prepared using tissue collected from healthy women undergoing cesarean delivery at term. Mechanical and enzymatic cell dispersions were carried out, and experiments were performed 24-28 h after cell plating. The prostaglandin E2 (PGE2) concentration in cultured medium was measured by RIA. Myometrial strips were obtained from the upper edge of the uterine incision during elective cesarean section at term. Dissected free of connective tissue, strips were mounted in a 30-mL two-chamber organ bath containing oxygenated Tyrode's buffer (37 C) and connected to a two-channel isometric smooth muscle transducer. Cultured decidual cells collected at term significantly increased the release of PGE2 in the presence of CRF (P < 0.01). The addition of CRF-BP did not significantly modify PGE2 release, but completely reversed the effect of CRF. When human myometrial strips were incubated in the presence of CRF and PGF2 alpha, a significant increase in contractile activity was observed (P < 0.01); preincubation with CRF-BP prevented the increased contractile activity induced by CRF. The present data show that CRF-BP is able to counteract the biological effect of CRF on human pregnancy endometrium and myometrium and suggest that CRF-BP may be a regulatory protein that plays a role in the local function of uterine tissues during pregnancy.


Assuntos
Proteínas de Transporte/farmacologia , Decídua/metabolismo , Dinoprostona/metabolismo , Miométrio/fisiologia , Gravidez/fisiologia , Contração Uterina/efeitos dos fármacos , Animais , Células Cultivadas , Cesárea , Hormônio Liberador da Corticotropina/farmacologia , Dinoprosta/farmacologia , Feminino , Humanos , Técnicas In Vitro , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Miométrio/efeitos dos fármacos , Ratos , Proteínas Recombinantes/farmacologia
17.
J Clin Endocrinol Metab ; 83(4): 1194-200, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9543140

RESUMO

Inhibins and activins are growth factors belonging to the transforming growth factor-beta) family and are known to influence cell proliferation and differentiation. Because transforming growth factor-beta is involved in physiological and tumoral changes of uterine tissues, the present study aimed to evaluate whether human normal and neoplastic endometrial and cervical epithelial cells express and secrete inhibin A, inhibin B, and activin A. To test this hypothesis, different approaches were used. By RT-PCR, the expression of specific messenger RNAs (mRNAs) for the inhibin alpha, activin betaA and betaB subunits, and activin receptor type II and type IIB was investigated: 1) in primary cultures of endometrial (stroma and epithelium) or cervical (epithelium) cells from healthy women; and 2) in specimens of endometrial or cervical carcinoma. To demonstrate a possible secretion of the proteins, dimeric inhibin A, inhibin B, and activin A were measured in culture medium of normal epithelial or stromal endometrial cells and in uterine washing fluid of healthy women or patients with endometrial adenocarcinoma. Levels of the proteins were also measured in serum of women with endometrial or cervical carcinoma. Cultured endometrial stromal or epithelial cells and epithelial cervical cells expressed inhibin alpha, activin betaA and betaB, and activin receptor type II and type IIB mRNAs. The same finding was obtained in specimens of endometrial or cervical carcinomas. Dimeric inhibin A, inhibin B, and activin A were measured in culture medium of both endometrial and cervical cells. In particular, resulting activin A levels were significantly higher in epithelial than in stromal cultured endometrial cells (P < 0.01). Dimeric proteins were also detected in the washing fluid of the uterine cavities of healthy women (controls) and with endometrial adenocarcinoma, in which higher activin A levels were found (P < 0.01 vs. controls). Women with endometrial carcinoma showed serum activin A levels significantly higher than healthy controls (P < 0.01), which significantly decreased after surgical removal of endometrial or cervical tumors (P < 0.01). The present study, for the first time, showed that inhibin A, inhibin B, and activin A, as well as activin receptors, are expressed in normal and neoplastic human uterine tissues. A secretion of activin A from tumoral cells into systemic circulation is suggested by the observation that the high levels in serum of patients with endometrial or cervical carcinoma decreased after the surgical removal of the tumor.


Assuntos
Neoplasias do Endométrio/sangue , Substâncias de Crescimento/sangue , Inibinas/biossíntese , Inibinas/sangue , Neoplasias do Colo do Útero/sangue , Útero/metabolismo , Receptores de Ativinas , Ativinas , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Inibinas/metabolismo , Pessoa de Meia-Idade , Fragmentos de Peptídeos/genética , RNA Mensageiro/biossíntese , Receptores de Fatores de Crescimento/genética , Valores de Referência , Células Tumorais Cultivadas
18.
J Clin Endocrinol Metab ; 78(1): 205-10, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8288705

RESUMO

The aim of the present study was to investigate the possible production, localization, and action of follistatin in human placenta, fetal membranes (amnion, chorion), and maternal decidua. Four different experimental approaches were used: 1) Southern blot analysis following reverse polymerase chain reaction to identify follistatin messenger RNA (mRNA) in tissue homogenates; 2) immunohistochemistry to localize immunoreactive (ir-) follistatin in the various intrauterine tissues; 3) measurement by RIA of ir-follistatin levels in culture medium of placental cells; and 4) possible action of follistatin on human CG (hCG) and progesterone release from cultured placental cells. Placental and decidual cells collected during first trimester or at term gestation express follistatin mRNA; fetal membranes (amnion, chorion) at term also express follistatin mRNA. Immunoreactive follistatin is localized in syncytial cells of placental villi at term as well as in large decidual cells, in amnion epithelium, and in chorionic cells. The placental secretion of follistatin has been confirmed by the evidence of measurable levels of ir-follistatin in the medium of cultured placental cells at term; the release is time dependent and is not modified by the addition of forskolin or progesterone. The addition of increasing doses of recombinant human follistatin does not significantly influence the release of hCG or progesterone from cultured placental cells, whereas the activin A-induced hCG and progesterone release are completely reversed. The present data showed that 1) human placenta, fetal membranes, and decidua express follistatin mRNA; 2) ir-follistatin is localized and released from placental cells at term; and 3) follistatin has a functional role in the local control system regulating placental hormone production.


Assuntos
Glicoproteínas/biossíntese , Glicoproteínas/fisiologia , Placenta/metabolismo , RNA Mensageiro/metabolismo , Sequência de Bases , Gonadotropina Coriônica/metabolismo , Feminino , Folistatina , Glicoproteínas/genética , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Reação em Cadeia da Polimerase , Gravidez , Progesterona/metabolismo , Distribuição Tecidual , Transcrição Gênica
19.
J Clin Endocrinol Metab ; 82(9): 2991-5, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9284732

RESUMO

Human placenta expresses subunit messenger RNAs for synthesizing inhibin A and B. Experimental studies have shown an effect of inhibins on placental hormone secretion, but an endocrine function is suggested by the high levels in maternal circulation. Although information is available on the changes of inhibin A in serum of healthy pregnant women, data on inhibin B levels are limited to early gestation. The aim of the present study was to investigate the changes of inhibin B levels in maternal circulation in healthy pregnant women throughout gestation, and to evaluate whether early pregnancy disturbances or gestational diseases are characterized by abnormal inhibin B levels. The protocol included various groups of pregnant women. A longitudinal evaluation of serum inhibin B levels was done at specific intervals (8-12, 13-18, 19-24, 25-28, 29-33, and 34-40 weeks) in the following groups: 1) healthy pregnant women (n = 13); 2) women at risk of hypertension who did not develop hypertension (n = 8); and 3) women with chronic hypertension (n = 13). In women in group 1, a blood sample was also obtained in the postpartum period (12, 24, and 48 h after delivery). Other pregnant women with abnormal bleeding in the first trimester were studied; they were subdivided into women with ongoing pregnancy (n = 12); and women with miscarriage (n = 22); a control group of healthy pregnant women at the same gestational age was also included (n = 18). A final group of women with gestational diseases (n = 34) was included in the study and included women with: 1) pregnancy-induced hypertension (n = 10); 2) preeclampsia (n = 17); and 3) intrauterine fetal growth retardation (n = 7). A group of healthy nonpregnant women (n = 9) was used as controls, and a blood specimen was collected during both the early- to midfollicular and midluteal phases of the menstrual cycle. Serum dimeric inhibin B levels were measured by using a double-antibody enzyme-linked immunoadsorbent assay. Early gestation inhibin B levels were similar to those of nonpregnant controls and showed a significant rise during the third trimester (P < 0.01). The highest maternal serum inhibin B levels were found at term (P < 0.01). Values significantly returned to control levels within 12-48 h (P < 0.01) after placental delivery. Women at risk of hypertension showed a similar gestational-related increase of inhibin B levels during the third trimester, without any significant difference when compared with healthy women. Women with chronic hypertension showed significantly lower levels at term (P < 0.01). Women with pregnancy-induced hypertension or preeclampsia, or who were carrying a fetus with intrauterine growth retardation showed serum inhibin B levels during the third trimester of gestation consistently lower than in control healthy women at the same gestational age (P < 0.001, mean +/- SEM). Maternal serum inhibin B levels in women with early pregnancy bleeding or miscarriage were similar to those of healthy pregnant women at the same gestational age, independent from the outcome of gestation. The present study showed that maternal serum inhibin B levels increase in the last trimester of normal pregnancy, with low levels in women with hypertensive disturbances or intrauterine growth retardation.


Assuntos
Inibinas/sangue , Inibinas/química , Complicações na Gravidez/sangue , Gravidez/sangue , Adulto , Dimerização , Feminino , Retardo do Crescimento Fetal/sangue , Humanos , Hipertensão/sangue , Estudos Longitudinais , Pré-Eclâmpsia/sangue , Complicações Cardiovasculares na Gravidez/sangue , Valores de Referência
20.
J Clin Endocrinol Metab ; 84(4): 1420-3, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199789

RESUMO

Urocortin is a new member of the CRF family. Multiple biological effects for urocortin have been shown in rats and in some in vitro models, showing a modulatory role in hormonal and behavioral functions. Human placenta expresses urocortin, but no information is available on the possible local biological actions. The aim of the present study was to evaluate the effect of urocortin on placental ACTH and prostaglandin (PG) secretion, as well as on myometrial contractility. Various in vitro models were used. For investigating the effect of urocortin on ACTH release, primary cultures of human trophoblast cells were used. Culture media, collected before and after 3 h exposure to different doses of urocortin and ACTH, were measured by RIA. Trophoblast tissue explants were incubated for 24 h in the presence of increasing doses of urocortin, and prostaglandin E2 (PGE2) levels were measured by RIA. Strips of myometrial tissue were incubated in an organ bath and connected to an isometric smooth-muscle transducer in the presence of urocortin, with or without prostaglandin F2alpha (PGF2a). In all these experiments, the effect of astressin (a CRF receptor antagonist) on urocortin-induced actions and the effect of equimolar doses of CRF were evaluated. A dose-related increase of trophoblast ACTH or PGE2 was induced by urocortin, whereas astressin inhibited urocortin-stimulated ACTH or PGE2 release. Equimolar doses of CRF showed a similar effect on both ACTH and PGE2. Urocortin increased PGF2alpha-induced myometrial contractility, and this effect was completely abolished by the addition of astressin. The present study showed that human urocortin stimulates placental secretion of ACTH and PGE2, and modulates myometrial contractility, suggesting a role for this peptide in placental and intrauterine CRF pathways.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Dinoprostona/metabolismo , Placenta/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Células Cultivadas , Dinoprosta/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Placenta/metabolismo , Gravidez , Urocortinas
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