954 resultados para HORMONAL


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BACKGROUND Observational studies of a putative association between hormonal contraception (HC) and HIV acquisition have produced conflicting results. We conducted an individual participant data (IPD) meta-analysis of studies from sub-Saharan Africa to compare the incidence of HIV infection in women using combined oral contraceptives (COCs) or the injectable progestins depot-medroxyprogesterone acetate (DMPA) or norethisterone enanthate (NET-EN) with women not using HC. METHODS AND FINDINGS Eligible studies measured HC exposure and incident HIV infection prospectively using standardized measures, enrolled women aged 15-49 y, recorded ≥15 incident HIV infections, and measured prespecified covariates. Our primary analysis estimated the adjusted hazard ratio (aHR) using two-stage random effects meta-analysis, controlling for region, marital status, age, number of sex partners, and condom use. We included 18 studies, including 37,124 women (43,613 woman-years) and 1,830 incident HIV infections. Relative to no HC use, the aHR for HIV acquisition was 1.50 (95% CI 1.24-1.83) for DMPA use, 1.24 (95% CI 0.84-1.82) for NET-EN use, and 1.03 (95% CI 0.88-1.20) for COC use. Between-study heterogeneity was mild (I2 < 50%). DMPA use was associated with increased HIV acquisition compared with COC use (aHR 1.43, 95% CI 1.23-1.67) and NET-EN use (aHR 1.32, 95% CI 1.08-1.61). Effect estimates were attenuated for studies at lower risk of methodological bias (compared with no HC use, aHR for DMPA use 1.22, 95% CI 0.99-1.50; for NET-EN use 0.67, 95% CI 0.47-0.96; and for COC use 0.91, 95% CI 0.73-1.41) compared to those at higher risk of bias (pinteraction = 0.003). Neither age nor herpes simplex virus type 2 infection status modified the HC-HIV relationship. CONCLUSIONS This IPD meta-analysis found no evidence that COC or NET-EN use increases women's risk of HIV but adds to the evidence that DMPA may increase HIV risk, underscoring the need for additional safe and effective contraceptive options for women at high HIV risk. A randomized controlled trial would provide more definitive evidence about the effects of hormonal contraception, particularly DMPA, on HIV risk.

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Abstract Background: Aromatase deficiency may result in a complete block of estrogen synthesis because of the failure to convert androgens to estrogens. In females, this results in virilisation at birth, ovarian cysts in prepuberty and lack of pubertal development but virilisation, thereafter. Objective and methods: We studied the impact of oral 17β-estradiol treatment on ovarian and uterine development, and on LH/FSH and inhibin B during the long-term follow-up of a girl harboring compound heterozygote point mutations in the CYP19A1 gene. Results: In early childhood, low doses of oral 17β-estradiol were needed. During prepuberty treatment with slowly increasing doses of E2 resulted in normal uterine and almost normal development of ovarian volume, as well as number and size of follicles. Regarding hormonal feedback mechanisms, inhibin B levels were in the upper normal range during childhood and puberty. Low doses of estradiol did not suffice to achieve physiological gonadotropin levels in late prepuberty and puberty. However, when estradiol doses were further increased in late puberty levels of both FSH and LH declined with estradiol levels within normal range. Conclusion: Complete aromatase deficiency provides an excellent model of how ovarian and uterine development in relation to E2, LH, FSH and inhibin B feedback progresses from infancy to adolescence.

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OBJECTIVES The intensity of post-egg retrieval pain is underestimated, with few studies examining post-procedural pain and predictors to identify women at risk for severe pain. We evaluated the influence of pre-procedural hormonal levels, ovarian factors, as well as mechanical temporal summation (mTS) as predictors for post-egg retrieval pain in women undergoing in vitro fertilization (IVF). METHODS Eighteen women scheduled for ultrasound-guided egg retrieval under standardized anesthesia and post-procedural analgesia were enrolled. Pre-procedural mTS, questionnaires, clinical data related to anesthesia and the procedure itself, post-procedural pain scores and pain medication for breakthrough pain were recorded. Statistical analysis included Pearson product moment correlations, Mann-Whitney U tests and multiple linear regressions. RESULTS Average peak post-egg retrieval pain during the first 24 hours was 5.0±1.6 on an NRS scale (0=no pain, 10=worst pain imaginable). Peak post-egg retrieval pain was correlated with basal antimullerian hormone (AMH) (r=0.549, P=0.018), pre-procedural peak estradiol (r=0.582, P=0.011), total number of follicles (r=0.517, P=0.028) and number of retrieved eggs (r=0.510, P=0.031). Ovarian hyperstimulation syndrome (OHSS) (n=4) was associated with higher basal AMH (P=0.004), higher peak pain scores (P=0.049), but not with peak estradiol (P=0.13). The mTS did not correlate with peak post-procedural pain (r=0.266, P=0.286), or peak estradiol level (r=0.090, P=0.899). DISCUSSION Peak post-egg retrieval pain intensity was higher than anticipated. Our results suggest that post-egg retrieval pain can be predicted by baseline AMH, high peak estradiol, and OHSS. Further studies to evaluate intra- and post-procedural pain in this population are needed, as well as clinical trials to assess post-procedural analgesia in women presenting with high hormonal levels.

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OBJECTIVES To prove non-inferiority of the first non-hormonal vaginal cream in Germany, Vagisan(®) Moisturising Cream (CREAM), compared to a non-hormonal vaginal gel (GEL) for vulvovaginal atrophy (VVA) symptom relief. METHOD This was a 12-week multicenter, open-label, prospective, randomized, two-period, cross-over phase-III trial. The primary endpoint was the cumulative VVA subjective symptom score of the respective treatment period. Secondary endpoints were assessment of single VVA subjective and objective symptoms, VVA objective symptom score, vaginal pH, safety parameters, overall assessment of efficacy, tolerability and evaluation of product properties. In total, 117 women were randomly allocated to either one of the two treatments, each administered for 4 weeks; 92 women were included in the per-protocol analysis (primary analysis). The main outcome measure was cumulative VVA subjective symptom score. RESULTS Regarding VVA symptom relief, results confirmed non-inferiority of CREAM compared to GEL and even indicated superiority of CREAM. Frequency and intensity of subjective symptoms and objective findings were clearly reduced, with CREAM showing better results compared to GEL. Mean VVA objective symptom score significantly decreased; improvement was significantly greater with CREAM. Vaginal pH decreased only following CREAM treatment. Tolerability was superior for CREAM: burning and itching, mostly rated as mild, occurred markedly less often with CREAM than with GEL. Overall satisfaction with treatment efficacy, tolerability and most product properties were rated significantly superior for CREAM. CONCLUSIONS Subjective and objective VVA symptoms were reliably and safely reduced by both non-hormonal topical products. However, efficacy and tolerability of CREAM were shown to be superior to GEL.

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BACKGROUND Endometriosis, the growth of endometrial tissue outside the uterine cavity, is associated with chronic pelvic pain, subfertility and an increased risk of ovarian cancer. Current treatments include the surgical removal of the lesions or the induction of a hypoestrogenic state. However, a reappearance of the lesion after surgery is common and a hypoestrogenic state is less than optimal for women of reproductive age. Additional approaches are required. Endometriosis lesions exist in a unique microenvironment characterized by increased concentrations of hormones, inflammation, oxidative stress and iron. This environment influences cell survival through the binding of membrane receptors and a subsequent cascading activation of intracellular kinases that stimulate a cellular response. Many of these kinase signalling pathways are constitutively activated in endometriosis. These pathways are being investigated as therapeutic targets in other diseases and thus may also represent a target for endometriosis treatment. METHODS To identify relevant English language studies published up to 2015 on kinase signalling pathways in endometriosis, we searched the Pubmed database using the following search terms in various combinations; 'endometriosis', 'inflammation', 'oxidative stress', 'iron', 'kinase', 'NF kappa', 'mTOR', 'MAPK' 'p38', 'JNK', 'ERK' 'estrogen' and progesterone'. Further citing references were identified using the Scopus database and finally current clinical trials were searched on the clinicaltrials.gov trial registry. RESULTS The current literature on intracellular kinases activated by the endometriotic environment can be summarized into three main pathways that could be targeted for treatments: the canonical IKKβ/NFκB pathway, the MAPK pathways (ERK1/2, p38 and JNK) and the PI3K/AKT/mTOR pathway. A number of pharmaceutical compounds that target these pathways have been successfully trialled in in vitro and animal models of endometriosis, although they have not yet proceeded to clinical trials. The current generation of kinase inhibitors carry a potential for adverse side effects. CONCLUSIONS Kinase signalling pathways represent viable targets for endometriosis treatment. At present, however, further improvements in clinical efficacy and the profile of adverse effects are required before these compounds can be useful for long-term endometriosis treatment. A better understanding of the molecular activity of these kinases, including the specific extracellular compounds that lead to their activation in endometriotic cells specifically should facilitate their improvement and could potentially lead to new, non-hormonal treatments of endometriosis.

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AIMS/HYPOTHESIS To investigate exercise-related fuel metabolism in intermittent high-intensity (IHE) and continuous moderate intensity (CONT) exercise in individuals with type 1 diabetes mellitus. METHODS In a prospective randomised open-label cross-over trial twelve male individuals with well-controlled type 1 diabetes underwent a 90 min iso-energetic cycling session at 50% maximal oxygen consumption ([Formula: see text]), with (IHE) or without (CONT) interspersed 10 s sprints every 10 min without insulin adaptation. Euglycaemia was maintained using oral (13)C-labelled glucose. (13)C Magnetic resonance spectroscopy (MRS) served to quantify hepatocellular and intramyocellular glycogen. Measurements of glucose kinetics (stable isotopes), hormones and metabolites complemented the investigation. RESULTS Glucose and insulin levels were comparable between interventions. Exogenous glucose requirements during the last 30 min of exercise were significantly lower in IHE (p = 0.02). Hepatic glucose output did not differ significantly between interventions, but glucose disposal was significantly lower in IHE (p < 0.05). There was no significant difference in glycogen consumption. Growth hormone, catecholamine and lactate levels were significantly higher in IHE (p < 0.05). CONCLUSIONS/INTERPRETATION IHE in individuals with type 1 diabetes without insulin adaptation reduced exogenous glucose requirements compared with CONT. The difference was not related to increased hepatic glucose output, nor to enhanced muscle glycogen utilisation, but to decreased glucose uptake. The lower glucose disposal in IHE implies a shift towards consumption of alternative substrates. These findings indicate a high flexibility of exercise-related fuel metabolism in type 1 diabetes, and point towards a novel and potentially beneficial role of IHE in these individuals. TRIAL REGISTRATION ClinicalTrials.gov NCT02068638 FUNDING: Swiss National Science Foundation (grant number 320030_149321/) and R&A Scherbarth Foundation (Switzerland).

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Submitted in partial fulfillment of the requirements for a Certificate in Orthodontics, Dept. of Orthodontics, University of Connecticut Health Center, 1976

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Background. In the United States, the incidence of pancreatic cancer has increased; more than 37,000 new cases of pancreatic cancer were diagnosed in the year 2007. Overall, the five-year survival rate is about 5% and pancreatic cancer ranks the fourth leading cause of cancer-related mortality among men and women. Despite the observed progress in cancer diagnosis and treatment, pancreatic cancer remains an unresolved significant public health problem in the United States. Familial pancreatic cancer has been confirmed to be responsible for approximately 10% of pancreatic cancer cases. However, 90% are still without known inherited predisposition. Until now, the role of oral contraceptive pills (OCPs) and hormonal replacement therapy (HRT) among women with pancreatic cancer remain unclear. We examined the association of exogenous hormonal uses in US women with risk of pancreatic cancer. ^ Methods. This was an active hospital-based case-control study which is conducted at the department of gastrointestinal medical oncology in The University of Texas M.D. Anderson Cancer Center. Between January 2005 and December 2007, a total of 287 women with pathologically confirmed pancreatic cancer (cases) and 287 healthy women (controls) were included in this investigation. Both cases and controls were frequency matched by age and race. Information about the use of hormonal contraceptives and hormonal replacement therapy (HRT) preparations as well as information about several risk factors of pancreatic cancer were collected by personal interview. Univariate and multivariate analyses were performed in this study to analyze the data. ^ Results. We found a statistical significant protective effect for use of exogenous hormone preparations on pancreatic cancer development (adjusted odds ratio [AOR], 0.4; 95% confidence interval [CI], 0.2–0.8). In addition, a 40% reduction in pancreatic cancer risk was observed among women who ever used any of the contraceptive methods including oral contraceptive pills (AOR, 6; 95% CI, 0.4–0.9). ^ Conclusions. Consistent with previous studies, the use of exogenous hormone preparations including oral contraceptive pills may confers a protective effect for pancreatic cancer development. More studies are warranted to explore for the underlying mechanism of such protection.^

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Prostate cancer (CaP) is the most diagnosed non-cutaneous malignancy and the second leading cause of cancer mortality among United States males. Major racial disparities in incidence, survival, as well as treatment persist. The mortality is three times higher among African Americans (AAs) compared with Caucasians. Androgen carcinogenesis has been persistently implicated but results are inconsistent; and hormone manipulation has been the main stay of treatment for metastatic disease, supportive of the androgen carcinogenesis. The survival disadvantage of AAs has been attributed to the differences in socioeconomic factors (SES), tumor stage, and treatment. We hypostasized that HT prolongs survival in CaP and that the racial disparities in survival is influenced by variation in HT and primary therapies as well as SES. To address these overall hypothesis, we first utilized a random-effect meta-analytic design to examine evidence from randomized trials on the efficacy of androgen deprivation therapy in localized and metastatic disease, and assessed, using Cox proportional hazards models, the effectiveness of HT in prolonging survival in a large community-based cohort of older males diagnosed with local/regional CaP. Further we examined the role of HT and primary therapies on the racial disparities in CaP survival. The results indicated that adjuvant HT compared with standard care alone is efficacious in improving overall survival, whereas HT has no significant benefit in the real world experience in increasing the overall survival of older males in the community treated for local/regional disease. Further, racial differences in survival persist and were explained to some extent by the differences in the primary therapies (radical prostatectomy, radiation and watchful waiting) and largely by SES. Therefore, given the increased used of hormonal therapy and the cost-effectiveness today, more RCTs are needed to assess whether or not survival prolongation translates to improved quality of life, and to answer the research question on whether or not the decreased use of radical prostatectomy by AAs is driven by the Clinicians bias or AAs's preference of conservative therapy and to encourage AAs to seek curative therapies, thus narrowing to some degree the persistent mortality disparities between AAs and Caucasians. ^

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Background. Primary liver cancer, the majority of which is hepatocellular carcinoma, is the third most common cause of mortality from cancer. It has one of the worst prognosis outcomes and an overall 5-year survival of only 5-6%. Hepatocellular carcinoma has been shown to have wide variations in geographic distribution and there is a marked difference in the incidence between different races and gender. Previously low-rate countries, including the US, have shown to have doubled the incidence of HCC during the past two decades. Even though the incidence of HCC is higher in males as compared to females, female hormones, especially estrogens have been postulated to have a role in the development of hepatocellular carcinoma on a molecular level. Despite the frequent usage of oral contraceptive pills (OCP) and previously, hormone replacement therapy (HRT), their role on HCC development has not been studied thoroughly. We aim to examine the association between exogenous hormone intake (oral contraceptives and post-menopausal hormone replacement therapy) and the development of HCC. Methods. This study is part of an ongoing hospital-based case-control study which is conducted at the Department of Gastrointestinal Oncology at The University of Texas M. D. Anderson Cancer Center. From January 2005 up to January 2008, a total of 77 women with pathologically confirmed hepatocellular carcinoma (cases) and 277 healthy women (controls) were included in the investigation. Information about the use of hormonal contraceptives, hormone replacement therapy and risk factors of hepatocellular cancer was collected by personal interview. Univariate and multivariate logistic regression analyses were done to estimate the crude odds ratios (OR) and adjusted odds ratios (AOR). Results. We found statistically significant protective effect for the use of HRT on the development of HCC, AOR=0.42 (95% CI, 0.21, 0.81). The significance was observed for estrogen replacement, AOR=0.43 (95% CI, 0.22, 0.83) and not for progesterone replacement, AOR=0.49 (95% CI, 0.10, 2.35). On the other hand, any hormonal contraceptive use, which encompasses oral contraceptive pills, implants and injections, did not show a statistical significance either in the crude OR=0.58 (95% CI, 0.33, 1.01) or AOR=0.56 (95% CI 0.26, 1.18). Conclusions. As corroborated by previous studies, HRT confers 58% HCC risk reduction among American women. The more important question of the association between hormonal contraceptives and HCC remains controversial. Further studies are warranted to explore the mechanism of the protective effect of HRT and the relationship between hormonal contraception and HCC.^

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Summary: Serum 25(OH)D levels decline without sunlight exposure. We studied 120 expeditioners to Antarctica to determine the skeletal and hormonal responses to sunlight deprivation. With emerging vitamin D insufficiency, serum calcium decreased, PTH increased, and bone loss at the proximal femur was observed. Baseline serum 25(OH)D levels >100 nmol/L prevented vitamin D insufficiency. Introduction: Vitamin D stores deplete without adequate sunlight exposure unless supplementation is provided. We studied 120 healthy adults who spent a year in Antarctica as a model for sunlight deprivation to define the timing and magnitude of the skeletal and hormonal responses to emerging vitamin D insufficiency. Methods: Fasting blood samples were assessed at baseline, 6 and 12 months for serum 25-hydroxyvitamin D (25(OH)D), osteocalcin (OC), bone formation (P1NP) and resorption (CTx), PTH and calcium. Lumbar spine and proximal femur BMD was measured using DXA. Differences over time were determined using repeated measures ANOVA. Percent changes were expressed as (Delta value/(value A +value B)/2)x100. Relationships between outcome measures were determined using Spearman's correlations. Results: Vitamin D insufficiency (<50 nmol/L) was observed in 85% of expeditioners by 6 months when serum calcium decreased and PTH increased (p<0.01). By 12 months, OC increased by 7.4±3.0% (p<0.05), and BMD decreased by 1.0±2.0% at the total proximal femur (p<0.05). For those with vitamin D sufficiency at baseline (>50 nmol/L), sunlight deprivation produced vitamin D insufficiency within 4 months unless baseline values were >100 nmol/L. Conclusion: Supplementation may be necessary for expeditioners with limited access to UV light.

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Pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone stimulate the gonads by regulating germ cell proliferation and differentiation. FSH receptors (FSH-Rs) are localized to testicular Sertoli cells and ovarian granulosa cells and are coupled to activation of the adenylyl cyclase and other signaling pathways. Activation of FSH-Rs is considered essential for folliculogenesis in the female and spermatogenesis in the male. We have generated mice lacking FSH-R by homologous recombination. FSH-R-deficient males are fertile but display small testes and partial spermatogenic failure. Thus, although FSH signaling is not essential for initiating spermatogenesis, it appears to be required for adequate viability and motility of the sperms. FSH-R-deficient females display thin uteri and small ovaries and are sterile because of a block in folliculogenesis before antral follicle formation. Although the expression of marker genes is only moderately altered in FSH-R −/− mice, drastic sex-specific changes are observed in the levels of various hormones. The anterior lobe of the pituitary gland in females is enlarged and reveals a larger number of FSH- and thyroid-stimulating hormone (TSH)-positive cells. The phenotype of FSH-R −/− mice is reminiscent of human hypergonadotropic ovarian dysgenesis and infertility.

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Full term pregnancy early in life is the most effective natural protection against breast cancer in women. Rats treated with chemical carcinogen are similarly protected by a previous pregnancy from mammary carcinogenesis. Proliferation and differentiation of the mammary gland does not explain this phenomenon, as shown by the relative ineffectiveness of perphenazine, a potent mitogenic and differentiating agent. Here, we show that short term treatment of nulliparous rats with pregnancy levels of estradiol 17β and progesterone has high efficacy in protecting them from chemical carcinogen induced mammary cancers. Because the mammary gland is exposed to the highest physiological concentrations of estradiol and progesterone during full term pregnancy, it is these elevated levels of hormones that likely induce protection from mammary cancer. Thus, it appears possible to mimic the protective effects of pregnancy against breast cancer in nulliparous rats by short term specific hormonal intervention.

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The pattern of expression of two genes coding for proteins rich in proline, HyPRP (hybrid proline-rich protein) and HRGP (hydroxyproline-rich glycoprotein), has been studied in maize (Zea mays) embryos by RNA analysis and in situ hybridization. mRNA accumulation is high during the first 20 d after pollination, and disappears in the maturation stages of embryogenesis. The two genes are also expressed during the development of the pistillate spikelet and during the first stages of embryo development in adjacent but different tissues. HyPRP mRNA accumulates mainly in the scutellum and HRGP mRNA mainly in the embryo axis and the suspensor. The two genes appear to be under the control of different regulatory pathways during embryogenesis. We show that HyPRP is repressed by abscisic acid and stress treatments, with the exception of cold treatment. In contrast, HRGP is affected positively by specific stress treatments.

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The role of the apical shoot as a source of inhibitors preventing fruit growth in the absence of a stimulus (e.g. pollination or application of gibberellic acid) has been investigated in pea (Pisum sativum L.). Plant decapitation stimulated parthenocarpic growth, even in derooted plants, and this effect was counteracted by the application of indole acetic acid (IAA) or abscisic acid (ABA) in agar blocks to the severed stump. The treatment of unpollinated ovaries with gibberellic acid blocked the effect of IAA or ABA applied to the stump. [3H]IAA and [3H]ABA applied to the stump were transported basipetally, and [3H]ABA but not [3H]IAA was also detected in unpollinated ovaries. The concentration of ABA in unpollinated ovaries increased significantly in the absence of a promotive stimulus. The application of IAA to the stump enhanced by 2- to 5-fold the concentration of ABA in the inhibited ovary, whereas the inhibition of IAA transport from the apical shoot by triiodobenzoic acid decreased the ovary content of ABA (to approximately one-half). Triiodobenzoic acid alone, however, was unable to stimulate ovary growth. Thus, in addition to removing IAA transport from the apical shoot, the accumulation of a promotive factor is also necessary to induce parthenocarpic growth in decapitated plants.