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41.
Aims/hypothesis Ghrelin is a natural growth hormone-releasing peptide thought to be involved in the regulation of energy metabolism. The recent studies concerning the association between ghrelin and insulin-like growth factor-I (IGF-I) concentrations have shown either negative correlation or no correlation at all. The aims of this study were to clarify the association between ghrelin and IGF-I concentrations in a large cohort and to characterize whether obesity, insulin resistance and type 2 diabetes affect this association.Methods We analysed fasting plasma ghrelin and IGF-I concentrations of 1,004 middle-aged subjects of the population-based OPERA study. Insulin resistance was estimated using QUICKI.Results IGF-I concentrations were negatively associated with ghrelin concentrations in the analysis of all subjects before (=–0.32, p<0.001) and after adjustments for BMI, insulin levels, sex and age (=–0.40, p<0.001). The association was particularly strong in males and in the higher BMI tertiles. The degree of association varied in relation to the glycaemic status: no insulin resistance: r2=6.5% (p<0.001), insulin resistance without type 2 diabetes: r2=21.0% (p<0.001), type 2 diabetes: r2=25.4 (p<0.001). IGF-I levels explained larger proportion (r2=9.8%) of the variation in ghrelin concentrations compared to fasting insulin concentration (r2=3.0%) and BMI (r2=1.5%).Conclusions/interpretation There is a negative and independent association between ghrelin and IGF-I concentrations in middle-aged subjects. The interaction between IGF-I and ghrelin is modified by obesity, IR and type 2 diabetes. Further studies are warranted to elucidate the role of ghrelin in the development of these states.  相似文献   
42.

Background:

It is now recognized that Cimicifuga foetida (C. foetida) extract is effective in alleviating menopausal symptoms. But the durations reported were usually short. The aim of this study was to investigate the effects of C. foetida extract therapy and different estrogen and progesterone sequential therapies, on the breasts of early postmenopausal women.

Methods:

This was a prospective randomized trial. Ninety-six early menopausal women were recruited and randomly assigned into three groups treated with different therapies for 2 years. Patients were given C. foetida extract in Group A, estradiol valerate and medroxyprogesterone acetate in Group B, and estradiol valerate and progesterone in Group C. Ultrasonography was used to monitor changes in breast during treatment.

Results:

In comparing breast glandular section thickness before and after 1 and 2 years of treatment, no significant difference was observed in Group A (11.97 ± 2.84 mm vs. 12.09 ± 2.58 mm and 12.61 ± 3.73 mm, P > 0.05); in Group B glandular section thickness had increased significantly (10.98 ± 2.34 mm vs. 11.84 ± 2.72 mm and 11.90 ± 3.33 mm, P < 0.05) after treatment, the same as Group C (11.56 ± 3.03 mm vs. 12.5 ± 3.57 mm and 12.22 ± 4.39 mm P < 0.05). In comparing breast duct width before and after 1 and 2 years of treatment, no significant difference was seen in Group A (1.07 ± 0.19 mm vs. 1.02 ± 0.18 mm and 0.98 ± 0.21 mm, P > 0.05); in Group B the duct width had a downward trend after treatment (0.99 ± 0.14 mm vs. 0.96 ± 0.22 mm and 0.90 ± 0.18 mm, P < 0.05), the same as Group C (1.07 ± 0.20 mm vs. 1.02 ± 0.17 mm and 0.91 ± 0.19 mm, P < 0.05). The nodules detected before treatment had disappeared after 1-year of treatment or exhibited no distinct changes in the three groups. However, new breast nodules had appeared after 2 years of treatment: There was one case in Group A, two cases in Group B and four cases in Group C, with breast hyperplasia after the molybdenum target check.

Conclusions:

In early postmenopausal patients, C. foetida extract therapy and estrogen and progesterone therapy at low doses did not increase the incidence of malignant breast tumors  相似文献   
43.
This prospective study investigated the relationship between anti-Müllerian hormone (AMH) level in the follicular fluid (FF) and the quality of the oocyte and embryo. A total of 65 FF samples from 54 women were included in this study. FF was collected from the largest preovulatory follicle sized≥20 mm of mean diameter from each ovary. Samples were divided into 3 groups according to the FF AMH levels: below the 33th percentile (low group, FF AMH<2.1 ng/mL, n=21), between the 33th and the 67th percentile (intermediate group, FF AMH=2.1-3.6 ng/mL, n=22), and above the 67th percentile (high group, FF AMH>3.6 ng/mL, n=22). The quality of the ensuing oocytes and embryos was evaluated by fertilization rate and embryo score. FF AMH levels correlated positively with the matched embryo score on day 3 after fertilization (r=0.331, P=0.015). The normal fertilization rate was significantly lower in the low group than in the intermediate group (61.9% vs. 95.5% vs. 77.3%, respectively, P=0.028). Our results suggest that the FF AMH level could be a predictor of the ensuing oocyte and embryo quality.

Graphical Abstract

相似文献   
44.
Background: Growth hormone (GH)–insulin‐like growth factor‐1 (IGF‐1) axis and gonadal hormones demonstrate extensively associated regulation; however, little is known about the effects of acute alcohol exposure on these hormones. This study examined the effects of intravenous alcohol on the GH–IGF‐1 axis and gonadal hormone concentrations, and the influence of age and sex on their regulation. Methods: Forty‐eight healthy volunteers (24 men and 24 women each in the 21 to 25 and 55 to 65 year age groups) underwent a 2‐session single‐blinded study. Subjects received in randomized counter‐balanced order, alcohol infusions, individually computed based on a physiologically based pharmacokinetic model, to maintain a steady‐state (“clamped”) exposure of 50 mg% or saline for 3 hours in separate sessions. Blood samples collected at baseline and postinfusion in each session were assayed for levels of GH, IGF‐1, free testosterone, and estradiol. Results: Acute alcohol administration resulted in changes in gonadal hormones that differed by sex. Change in free testosterone showed a significant treatment × baseline interaction (p < 0.001), indicating that alcohol‐induced suppression of testosterone occurred predominantly in men. On the other hand, change in estradiol showed a significant treatment × sex interaction (p = 0.028), indicating that alcohol‐induced increases in estradiol occurred predominantly in women. There was a trend for alcohol‐induced decreases in IGF‐1 levels. Change in GH showed a significant main effect of baseline (p < 0.001) and a trend for treatment by baseline interaction, suggesting an alcohol‐induced decrease in individuals with high baseline GH values. There was also a significant main effect of sex (p = 0.046) indicating that men had greater changes in GH across treatment compared with women. Conclusions: Alcohol induced a complex pattern of hormonal responses that varied between younger and older men and women. Some of the observed sex‐based differences may help improve our understanding of the greater susceptibility to alcohol‐related hepatic damage seen in women.  相似文献   
45.
46.
The study was aimed to evaluate the effects of levothyroxine (LT4) supplemental replacement treatment for pregnancy and analyze the associations between the clinical classification of hypothyroidism and reduced thyroid-stimulating hormone (TSH) in LT4 therapy. Totally, 195 pregnant women with hypothyroidism receiving routine prenatal care were enrolled. They were categorized into three groups: overt hypothyroidism (OH), subclinical hypothyroidism (SCH) with negative thyroperoxidase antibody (TPOAb), and SCH with positive TPOAb. The association between the clinical classification and reduced TSH in LT4 supplemental replacement treatment was assessed. The results indicated that reduced TSH was significantly different among the groups according to the clinical classifications (p?=?0.043). The result was also significantly different between patients with OH and patients with SCH and negative TPOAb (p?=?0.036). Similar result was reported for the comparison between patients with OH and patients with SCH and positive TPOAb (p?=?0.016). Multiple variable analyses showed that LT4 supplementation, gestational age and the variable of clinical classifications were associated with reduced TSH independently. Our data suggested that the therapeutic effect of substitutive treatment with LT4 was significantly associated with different clinical classifications of hypothyroidism in pregnancy and the treatment should begin as soon as possible after diagnosis.  相似文献   
47.
48.
Burger HG 《Maturitas》2007,57(1):6-10
Two randomised controlled trials of hormone therapy (HT) were conducted within the US Women's Health Initiative. Both were chronic disease prevention trials, undertaken to determine whether HT reduced cardiovascular risk and increased breast cancer risk. Because the majority of subjects in both trials were asymptomatic and many years postmenopausal, and because substantial numbers had received HT prior to recruitment to the trials, care must be taken in drawing conclusions that the observed risks are applicable to women for whom HT is conventionally prescribed. Each of the reported risks must be examined critically to determine its likely applicability to symptomatic women treated for two to three years to relieve symptoms, but sometimes for substantially longer periods. Further, the risks reported in each of the two trials must be considered separately. Concerning cardiovascular disease, many subjects in the trials were at increased baseline risk because of their age, body mass index, smoking status, blood pressure and years since menopause, in contrast to the usual situation for symptomatic perimenopausal women. Therefore the reported overall cardiovascular risks in WHI, in both treatment arms, should be regarded as irrelevant to menopause management. In contrast, breast cancer risk is relevant, providing that proper note is taken of the fact that there was no increased risk after five years of combined hormone therapy in non-prior HT users and there was a tendency to a decreased risk in oestrogen only treated individuals. Other risks are analysed similarly.  相似文献   
49.
OBJECTIVES: Current recommendations for hormone therapy (HT) are mainly based on findings from studies using standard dose regimens in older women who had a different health profile from those who start HT soon after the onset of menopause. METHODS: We, therefore, reviewed controlled trials assessing the efficacy, safety and tolerability of low-dose oral continuous combined HT (cc-HT) started for treatment of climacteric symptoms. This review is limited to oral cc-HT regimens over sequential regimens as most postmenopausal women prefer not to have a return of uterine bleeding, and to studies of at least 2 years in duration. RESULTS: Low-dose cc-HT is effective in alleviating climacteric symptoms and in maintaining bone density over prolonged periods, although no data were available regarding fracture risk. No increased risk of coronary heart disease, venous thrombo-embolism or stroke during the use of low-dose cc-HT was reported in the long-term studies and no definitive evidence for an increased risk of breast cancer was found. Breakthrough bleeding during the first months of use is less common than with standard dose HT and amenorrhoea is achieved in most women over time. These regimens are safe for the endometrium and are well tolerated, with a low incidence of adverse events compared with standard doses. CONCLUSIONS: Current evidence from controlled trials indicates that low-dose oral cc-HT appears effective and safe. This makes it a good choice for the alleviation of climacteric symptoms, and for this purpose long-term administration of low-dose cc-HT does not seem to impose serious health risks. However, more long-term study data and direct head-to-head comparisons between various low-dose preparations are needed to support or rectify the safety aspects.  相似文献   
50.
OBJECTIVES: The purpose of this study was to examine the pattern of and factors that influence hot flash severity across the menopausal transition (MT) and early postmenopause (PM). METHODS: Women from the Seattle Midlife Women's Health Study (N=302) provided data for these analyses: at least one annual health questionnaire and a menstrual calendar. A subset of women provided a first morning voided urine specimen from 1997 through 2005. Urine samples were assayed for estrone glucuronide and FSH. Linear mixed effects modeling was used to identify change in hot flash severity scores over time, including the relationship to age, MT-related, psychosocial and lifestyle factors. RESULTS: Increases in hot flash severity were associated with late transition stage, early postmenopause, use of HRT, duration of early transition stage, age of entry into early PM and level of FSH. Age of entry into early transition and estrone levels were associated with decreased hot flash severity. Not associated with hot flash severity were being in early transition stage, age of entry into or duration of late transition stage and all of the psychosocial (anxiety, stress, depressed mood) and lifestyle variables (BMI, activity level, sleep, alcohol use). CONCLUSIONS: Variables associated with reproductive aging independently predicted changes in hot flash severity; psychosocial and lifestyle variables did not. The effect of age dropped out when factors associated with reproductive aging were considered. Use of HRT ameliorated but did not eliminate severe hot flashes suggesting that there is room for alternative approaches less likely to cause harm.  相似文献   
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