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Serum Estradiol (serum + estradiol)
Terms modified by Serum Estradiol Selected AbstractsLetrozole normalizes serum testosterone in severely obese men with hypogonadotropic hypogonadismDIABETES OBESITY & METABOLISM, Issue 3 2005H. De Boer Background:, Morbid obesity is associated with increased estradiol production as a result of aromatase-dependent conversion of testosterone to estradiol. The elevated serum estradiol levels may inhibit pituitary LH secretion to such extent that hypogonadotropic hypogonadism can result. Normalization of the disturbed estradiol-testosterone balance may be beneficial to reverse the adverse effects of hypogonadism. Aim:, To examine whether aromatase inhibition with Letrozole can normalize serum testosterone levels in severely obese men with hypogonadotropic hypogonadism. Patients and Methods:, Ten severely obese men, mean age 48.2 ± 2.3 (s.e.) years and body mass index 42.1 ± 2.6 kg/m2, were treated with Letrozole for 6 weeks in doses ranging from 7.5 to 17.5 mg per week. Results:, Six weeks of treatment decreased serum estradiol from 120 ± 20 to 70 ± 9 pmol/l (p = 0.006). None of the subjects developed an estradiol level of less than 40 pmol/l. LH increased from 4.5 ± 0.8 to 14.8 ± 2.3 U/l (p < 0.001). Total testosterone rose from 7.5 ± 1.0 to 23.8 ± 3.0 nmol/l (p < 0.001) without a concomitant change in sex hormone-binding globulin level. Those treated with Letrozole 17.5 mg per week had an excessive LH response. Conclusion:, Short-term Letrozole treatment normalized serum testosterone levels in all obese men. The clinical significance of this intervention remains to be established in controlled, long-term studies. [source] Necessity of re-evaluation of estramustine phosphate sodium (EMP) as a treatment option for first-line monotherapy in advanced prostate cancerINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2001Tadaichi Kitamura Abstract Estramustine phosphate sodium (EMP) was first introduced in the early 1970s for the treatment of prostate cancer, when EMP was supposed to have the dual effect of estrogenic activity and cytotoxicity. For the following decades, it was used mainly in hormone-refractory cases, with a conventional dosage of 4,9 capsules/day, which showed a 30,35% objective response rate. However, a very limited number of cases have been reported that used EMP as a first-line monotherapy in the conventional dosage. One study showed a response rate of 82%, which is at least as effective as conventional estrogen (diethylstilbestrol; DES) monotherapy. Nevertheless, EMP was almost abandoned for the treatment of prostate cancer because of severe adverse side-effects, especially in the cardiovascular system and gastrointestinal tract. Recently, two facts have become evident. First, EMP interferes with cellular microtubule dynamics but does not show alkylating effects. Second, EMP is able to produce a complex with calcium when dairy products are taken concomitantly with EMP, resulting in a decrease in the absorption rate of EMP from the gut. Many clinical trials have been undertaken without warning against concomitant dairy product intake since the introduction of EMP. This fact will jeopardize almost all the clinical trials performed before 1990. It is considered that response rates have been underestimated and better results could have been obtained because side-effects decrease dose-dependently. Low-dose EMP monotherapy (2 capsules/day) has been performed infrequently in previously untreated advanced prostate cancer. The only large trial by the European Organization for Research and Treatment of Cancer in 1984 was biased in selecting patients. Nevertheless, the response rate of EMP is comparable to that of DES. In this study, the adverse side-effects of EMP were less than that of DES. Recently, a study was conducted at the University of Tokyo of 11 patients with advanced prostate cancer on low-dose EMP as first-line monotherapy. The study found that the mean serum prostate-specific antigen level decreased to within the normal range by day 50; mean serum testosterone, leutinizing hormone and follicle-stimulating hormone reduced to undetectable levels by day 20; and mean serum estradiol increased to a very high level within 1 week. These data implicate that low-dose EMP can suppress quickly and adequately the pituitary,gonadal axis, although the antitumor effect has not as yet been elucidated. For these reasons, it is necessary to re-evaluate low-dose EMP monotherapy in previously untreated advanced prostate cancer. [source] The contribution of hepatic steroid metabolism to serum estradiol and estriol concentrations in nonylphenol treated MMTVneu mice and its potential effects on breast cancer incidence and latencyJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2005Ricardo Acevedo Abstract The two major pathways for the metabolism of estradiol-17, (E2) are the 2- and 16-hydroxylase pathways. Research has suggested that the increased production of the estrogenically active 16-hydroxy products such as estriol (E3) may be involved in increased susceptibility to breast cancer. 4-Nonylphenol (4-NP) is an environmental estrogen that also can activate the pregnane-X receptor (PXR) and induce P-450 enzymes responsible for the production of E3. It is hypothesized that 4-NP may act in part as an environmental estrogen by increasing E3 production. Based on its affinity for the estrogen receptor (ER) alone, 4-NP may be more potent than predicted at increasing mammary cancer incidence in the MMTVneu mouse. Female mice were treated per os for 7 days at 0, 25, 50 or 75 mg kg,1 day,1 4-NP to investigate the effects of 4-NP on hepatic estrogen metabolism after an acute treatment. 4-Nonylphenol increased the hepatic formation of E3 in a dose-dependent manner. However, serum E3 concentrations were only increased at 25 mg kg,1 day,1 presumably due to direct inhibition of E3 formation by 4-NP. MMTVneu mice were then treated for 32 weeks at 0, 30 or 45 mg kg,1 day,1 4-NP to determine its effects on mammary cancer formation and estrogen metabolism. 4-Nonylphenol increased mammary cancer formation in the MMTVneu mice at 45 mg kg,1 day,1 but not at 30 mg kg,1 day,1. Mice treated with an equipotent dose of E2, 10 µg kg,1 day,1, based on the relative binding affinities of nonylphenol and estradiol for ER,, did not develop mammary cancer. This suggests that nonylphenol is more potent than predicted based on its affinity for the estrogen receptor. However, no changes in serum E3 concentrations or hepatic E3 production were measured after the chronic treatment. Changes in E3 formation were correlated with increased CYP2B levels after the 7 day 4-NP treatment, and repression of CYP2B and CYP3A after 32 weeks of 4-NP treatment. Microarray analysis and Q-PCR of liver mRNA from the mice treated for 32 weeks demonstrated a decrease in RXR,, the heterodimeric partner of the PXR, which may in part explain the repressed transcription of the P450s measured. In conclusion, 4-NP treatment for 32 weeks increased mammary cancer formation at a dose of 45 mg kg,1 day,1. However, chronic treatment with 4-NP did not increase hepatic E3 formation or serum E3 concentrations. The transient induction by 4-NP of hepatic E3 formation and serum concentrations is most likely not involved in the increased incidence of mammary cancer in MMTVneu mice since E3 serum concentrations were only increased at 25 mg kg,1 day,1, a dose that was not sufficient to induce mammary tumor formation. Nevertheless, the induced hepatic E3 production in the acute exposures to 4-NP was indicative of an increase in mammary cancer incidence after the chronic exposure. Copyright © 2005 John Wiley & Sons, Ltd. [source] Ovarian follicular development stimulated by leuprorelin acetate plus human menopausal gonadotropin in chimpanzeesJOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2005Nobuhiko Yoshimoto Abstract:, We attempted ovarian stimulation using gonadotropins in 14 chimpanzees. Subjects were given a single administration of leuprorelin acetate, followed by repeated administration of human menopausal gonadotropin (hMG) for 16,21 days. During the dosing period, the ovarian follicle diameter and count were measured by transvaginal ultrasonography. The hormone administration induced the development of multiple follicles, and multiple oocytes were subsequently retrieved. However, the follicle count was decreased, suggesting atresia, in some subjects. Statistically, the final follicle diameter was dependent on the dosing duration and the hMG dose in the late stage, while the maximum follicle count during hMG administration was dependent on age and the hMG dose in the early stage. Five subjects showed mild ovarian hyperstimulation syndrome (OHSS)-like symptoms with a high serum estradiol (E2) concentration. These results suggest that leuprorelin acetate plus hMG administration successfully stimulates the development of multiple ovarian follicles for oocyte retrieval and that the serum E2 concentration is predictive of OHSS-like symptoms in chimpanzees. [source] Stimulation day-six serum estradiol: A predictive indicator for the probability of embryo cryopreservation in IVF/ICSI cyclesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2009Hassan A. El Maghraby Abstract Objective:, To evaluate the predictive value of stimulation day six serum estradiol (E2) for the probability of embryo cryopreservation after fresh embryo transfer in intracytoplasmic sperm injection (ICSI) cycles. Subjects and Methods:, The study included 282 ICSI cycles for different causes of infertility, provided that the age of the female partner was <40 years and her basal follicle stimulating hormone <10 IU/L. Setting:, Alexandria IVF/ICSI center. Main Outcome Measures:, Primary outcome measures are stimulation day-six serum E2, and rate of embryo cryopreservation, after transfer of three good-quality embryos. Secondary outcome measures are pregnancy rate per fresh embryo transfer, and other intermediate variables of the ICSI cycle. Results:, Patients were stratified into three groups according to day-six serum E2 levels: Group I with values <400 pg/mL; Group II, between 400 and 900; and Group III with values >900. The mean number of oocytes retrieved was 6.3, 8.9, and 12.4; the mean number of obtained embryos was 3.3, 4.8, and 6.7; and pregnancy rates were 18.1, 36.2, and 44.7% in the three groups, respectively. Rate of embryo cryopreservation, after transfer of three good-quality embryos was 70.7% in Group III, and 26.5% in Group I. (P = 0.01). The negative predictive value of day-six E2 < 400 pg/mL for freezing was 83% while day-six serum E2 > 900 pg/mL has a sensitivity of 55%, specificity of 72% and positive predictive value of 50% for embryo freezing. Conclusion:, Higher stimulation day-six estradiol was associated with a higher probability of cryopreservation, and a higher pregnancy rate. [source] The mRNA expression of P450 aromatase, gonadotropin ,-subunits and FTZ-F1 in the orange-spotted grouper (Epinephelus Coioides) during 17,-methyltestosterone-induced precocious sex changeMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2007Weimin Zhang Abstract The orange-spotted grouper Epinephelus coioides is a protogynous hermaphroditic fish, but the physiological basis of its sex change remains largely unknown. In the present study, the 2-year-old orange-spotted grouper was induced to change sex precociously by oral administration of 17,-methyltestosterone (MT, 50 mg/Kg diet, twice a day at daily ration of 5% bodyweight) for 60 days. The serum testosterone levels were significantly elevated after MT treatment for 20 and 40 days as compared to control, but the levels of serum estradiol (E2) remained unchanged. The expression of P450aromA in the gonad significantly decreased after MT treatment for 20, 40, and 60 days. Accordingly, the enzyme activity of gonadal aromatase was also lower. The expression of FSH, subunit in the pituitary was significantly decreased after MT treatment for 20 days, but returned to the control levels after 40 and 60 days; however, the expression of LH, subunit was not altered significantly by MT treatment. The expression of FTZ-F1 in the gonad also decreased significantly in response to MT treatment for 40 and 60 days, but its expression in the pituitary was not altered significantly. Interestingly, when tested in vitro on ovarian fragments, MT had no direct effect on the expression of P450aromA and FTZ-F1 as well as the activity of gonadal aromatase, suggesting that the inhibition of gonadal P450aromatase and FTZ-F1 by MT may be mediated at upper levels of the brain-pituitary-gonadal axis. Taken together, these results indicated that FSH, P450aromA, FTZ-F1, and serum testosterone are associated with the MT-induced sex change of the orange-spotted grouper, but the cause,effect relationship between these factors and sex change in this species remains to be characterized. Mol. Reprod. Dev. 74: 665,673, 2007. © 2006 Wiley-Liss, Inc. [source] Herba Epimedii water extract elevates estrogen level and improves lipid metabolism in postmenopausal womenPHYTOTHERAPY RESEARCH, Issue 9 2008Fang-Fang Yan Abstract Hormone replacement therapy (HRT) can ameliorate lipid metabolism after menopause, but it is not suitable for long-term use because of serious side effects. Herba Epimedii is a widely used herbal medicine in many Asian countries, it potentially treats menopausal syndrome and its complications with few side effects and good curative effects. The study aimed to evaluate the effects of Herba Epimedii water extract on blood lipid and sex hormone levels. Ninety subjects were randomly divided into two groups: a trial group which received Herba Epimedii water extract and a control group which was administered an equal amount of water placebo. At the baseline and after 6 months of medication, serum estradiol (E2), progesterone (P), testosterone (T), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) concentrations were measured. The results indicated that Herba Epimedii water extract decreased the TC and TG levels (p < 0.01). Furthermore, Herba Epimedii water extract significantly increased the serum level of E2 (p < 0.01) compared with the pre-treatment level. In conclusion, Herba Epimedii water extract produces its beneficial actions in postmenopausal women. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||