BACKGROUND & AIMS: OBJECTIVE:Cross-sectional data suggest that obesity, particularly central obesity, may be associated with decreased production of sex steroid hormones in men. However, longitudinal hormone data on men in relation to obesity status are limited. Previous studies have not consistently demonstrated whether sex steroids are associated specifically to body mass index or to measures of central obesity. Our objective was to examine the relation of obesity (body mass index > 30 kg/m2), and of central obesity (waist circumference > 100 cm or waist to hip ratio > 0.95) to longitudinal change in sex steroid hormones in men. DESIGN:Prospective follow-up of a population-based sample of men in Boston. PATIENTS:Nine hundred forty-two (942) men in the Massachusetts Male Ageing Study with complete anthropometry and hormone data at baseline (1987-1989, ages 40-70) and follow-up (1995-1997). MEASUREMENTS:Free and total testosterone (FT and TT), dehydroepiandrosterone sulphate (DHEAS), and sex hormone-binding globulin (SHBG) were assessed using standardized methods. Health behaviours and medical history were obtained by structured interview. Repeated measures regression was used to describe trends in steroid hormones and SHBG in relation to obesity status, adjusting for age, smoking, alcohol, comorbidities, and physical activity. RESULTS:Obesity was associated with decreased levels of total and free testosterone, and of SHBG at follow-up relative to baseline. For any given baseline concentration of TT, FT or SHBG, follow-up levels were lowest among men who remained obese or who became obese during follow-up. This was true for all three indices of obesity. Central adiposity was associated with lower DHEAS levels at follow-up, while elevated body mass index was not. CONCLUSIONS:Obesity may predict greater decline in testosterone and SHBG levels with age. Central adiposity may be a more important predictor of decline in DHEAS than is body mass index.

背景与目标：

BACKGROUND & AIMS: AIM:To evaluate the tissular expression of Androgen (A), Estrogen (E) and Progesterone (Pg) receptors, and Apolipoprotein D (ApoD), in liver tumors from resected hepatocellular carcinoma (HCC) cases in order to assess their possible relationship to prognosis. METHODS:We performed an immunohistochemical study using tissue microarrays (containing more than 260 cancer specimens, from 31 HCC patients and controls) to determine the presence of specific antibodies against AR, ER, PgR and ApoD, correlating their findings with several clinico-pathological and biological variables. The staining results were categorized using a semi-quantitative score based on their intensity, and the percentage of immunostained cells was measured. RESULTS:A total of 21 liver tumors (67.7%) were positive for AR; 16 (51.6%) for ER; 26 (83.9%) for PgR and 12 (38.7%) stained for ApoD. We have found a wide variability in the immunostaining score values for each protein, with a median (range) of 11.5 (11.5-229.5) for AR; 11.1 (8.5-65) for ER; 14.2 (4-61) for PgR; and 37.7 (13.8-81.1) for ApoD. A history of heavy ethanol consumption, correlated positively with AR and PgR and negatively with ER status. HCV chronic infection also correlated positively with AR and PgR status. However, the presence of ApoD immunostaining did not correlate with any of these variables. Tumors with a positive immuno-staining for PgR showed a better prognosis. CONCLUSION:Our results indicate a moderate clinical value of the steroid receptor status in HCC, emphasizing the need to perform further studies in order to evaluate the possible role of new hormonal-based therapies.

背景与目标：

BACKGROUND & AIMS: :The purpose of this study was to evaluate the effect of female sexual hormones on intestinal and serum cytokines following traumatic brain injury (TBI). Adult female rats were ovariectomized and distributed among the following 9 groups: (i) sham trauma, (ii) TBI (Marmarou's method), (iii) vehicle (dimethylsulfoxide) treated, (iv) estrogen (E2) treated, (v) progesterone (P) treated, (vi) treated with E2+P, (vii) propylpyrazole triol (PPT) treated, (viii) diarylpropionitrile (DPN) treated, and (ix) control. PPT and DPN are estrogen receptor αand β agonists, respectively. Serum and intestinal levels of interleukin (IL)-1β were increased by TBI (P < 0.001). The level of intestinal IL-1β was increased in the group treated with E2 (P < 0.001). There was a reduction in serum IL-1β (P < 0.01) and an increase in intestinal IL-1β level (P < 0.001) in the PPT-treated group compared with the vehicle-treated group. TBI reduced serum IL-6 (P < 0.01) and increased intestinal IL-6 (P < 0.001). Serum IL-6 was increased in the group treated with E2 (P < 0.001), P (P < 0.001), E2+P (P < 0.01), and DPN (P < 0.001) after TBI; however, intestinal IL-6 was higher in the E2-treated group compared with the vehicle-treated group (P < 0.01). Intestinal tumor necrosis factor α (TNF-α) was increased by TBI (P < 0.001). Progesterone decreased serum TNF-α (P < 0.01). Intestinal TNF-α in the E2 (P < 0.01), E2+P (P < 0.001), and PPT (P < 0.001) treatment groups was less than in the vehicle-treated group. In conclusion, estrogen influences the intestinal levels of proinflammatory cytokines, in particular TNF-α, mediated through estrogen receptor α.

背景与目标： : 这项研究的目的是评估女性性激素对创伤性脑损伤 (TBI) 后肠道和血清细胞因子的影响。成年雌性大鼠卵巢切除并分布在以下9组中 :( i) 假创伤，(ii) TBI (Marmarou's方法)，(iii) 载体 (二甲基亚砜) 治疗，(iv) 雌激素 (E2) 治疗，(v) 孕激素 (P) 治疗，(vi) 用E2 P处理，(vii) 丙基吡唑三醇 (PPT) 处理，(viii) 二芳基丙腈 (DPN) 处理，以及 (ix) 对照。PPT和DPN分别是雌激素受体 α 和 β 激动剂。血清和肠道白细胞介素 (IL)-1β 水平升高 (P <0.001)。E2治疗组肠IL-1β 水平升高 (P <0.001)。与载体治疗组相比，PPT治疗组的血清IL-1β 降低 (P <0.01)，肠IL-1β 水平升高 (P <0.001)。TBI降低血清IL-6 (P <0.01)，增加肠道IL-6 (P <0.001)。TBI后，E2 (P <0.001)，P (P <0.001)，E2 P (P < 0.01) 和DPN (P < 0.001) 治疗组的血清IL-6升高; 但是，与载体治疗组相比，E2-treated组的肠道IL-6更高 (P <0.01)。TBI可使肠道肿瘤坏死因子 α (TNF-α) 升高 (P <0.001)。孕酮降低血清TNF-α (P <0.01)。E2 (P <0.01)，E2 P (P < 0.001) 和PPT (P < 0.001) 治疗组的肠道TNF-α 少于媒介物治疗组。总之，雌激素会影响通过雌激素受体 α 介导的促炎细胞因子 (尤其是TNF-α) 的肠道水平。

BACKGROUND & AIMS: Human endometrium undergoes sequential changes during the menstrual cycle and becomes receptive to implantation during a defined period in the secretory phase. We attempted to identify the genes expressed during this period by representational difference analysis (RDA). When the cDNAs of a proliferative endometrium were used as the driver and the cDNAs of a post-ovulatory day 5 endometrium were used as the tester, a number of bands were identified by RDA. DNA of the cloned RDA products revealed that the majority of the clones contained a fragment of a cDNA identical to that of a crystallin B chain. Northern blot analysis showed that the expression of the alpha crystallin B chain mRNA was absent during the proliferative phase. The expression of the mRNA of alpha crystallin B chain first appeared in the secretory phase, progressively increased during this phase and peaked in the late secretory endometria. The pattern of expression of alpha crystallin B chain mRNA in the endometrium of mature cycling baboons (Papio anubis) was similar to that seen in human endometrium. As revealed by Western blot analysis, the expression of the alpha crystallin B chain protein in human endometrium followed a pattern of expression similar to its mRNA. At the cellular level, the immunoreactive protein first appeared in the surface epithelial cells of human endometrium within the implantation window without significant immunoreactivity in the underlying glandular cells. During the mid- and late secretory phases, the intensity of staining in the epithelial cells was enhanced and an intense immunoreactivity was developed in the glandular epithelium, alpha crystallin B chain was virtually an epithelial product and no immunoreactivity for this protein was detectable in the stromal cells, endothelial cells or lymphoid cells. The expression of alpha crystallin B chain could be regulated, by medroxy progesterone acetate as well as by oestrogen withdrawal, in human endometrial carcinoma cells (EnCa-101), transplanted to nude mice. Based on the data presented here, the known function of alpha crystallin B chain and its distinct pattern of expression in human endometrium, we suggest that this protein is an important factor within the molecular repertoire that makes endometrium receptive to implantation.

背景与目标： 人子宫内膜在月经周期中经历顺序变化，并在分泌期的特定时期接受植入。我们试图通过代表性差异分析 (RDA) 来鉴定在此期间表达的基因。当将增生性子宫内膜的cdna用作驱动程序，并将排卵后第5天子宫内膜的cdna用作测试仪时，RDA鉴定出许多条带。克隆的RDA产物的DNA显示，大多数克隆包含与晶体蛋白B链相同的cDNA片段。Northern印迹分析表明，在增殖期不存在 α 晶体蛋白B链mRNA的表达。Α 晶体蛋白B链mRNA的表达首先出现在分泌期，在此期逐渐增加，并在分泌期晚期子宫内膜达到峰值。成熟循环狒狒 (Papio anubis) 子宫内膜中 α 晶体蛋白B链mRNA的表达模式与人子宫内膜中相似。如Western印迹分析所示，人子宫内膜中 α 晶体蛋白B链蛋白的表达遵循与其mRNA相似的表达模式。在细胞水平上，免疫反应蛋白首先出现在植入窗口内的人子宫内膜表面上皮细胞中，而在下层腺体细胞中没有显着的免疫反应性。在分泌期中期和晚期，上皮细胞的染色强度增强，腺上皮细胞产生了强烈的免疫反应性，α 晶体蛋白B链实际上是上皮产物，在基质细胞，内皮细胞或淋巴样细胞中没有检测到该蛋白的免疫反应性。在移植到裸鼠的人子宫内膜癌细胞 (EnCa-101) 中，醋酸甲羟孕酮和雌激素戒断可以调节 α 晶体蛋白B链的表达。根据此处提供的数据，已知的 α 晶体蛋白B链的功能及其在人子宫内膜中的独特表达模式，我们建议该蛋白是使子宫内膜易于植入的分子库中的重要因素。

BACKGROUND & AIMS: :BD-II and BD-IX male and female rats received weekly subcutaneous (s.c.) injections of 15 mg/kg 1,2-dimethylhydrazine dihydrochloride (DMH) beginning at either 35, 120 or 210 days of age and continuing for 20 weeks. Control animals received only the DMH vehicle. Additional BD-II and BD-IX male and female rats of the three age groups were gonadectomized at 21, 106 and 196 days. Beginning 14 days after gonadectomy, the rats received 15 mg/kg of DMH by s.c. injection once a week for 20 weeks. Animals were sacrificed 35 weeks after the initial DMH injection. Control rats of the appropriate age and sex did not develop colon tumors. BD-IX rats are apparently more sensitive to DMH than BD-II rats. The incidence of DMH-induced cancer is less in females than in males in both the BD-II and BD-IX animals. Gonadectomy does not affect cancer incidence in either BD-II males or females nor in the BD-IX females but reduced the incidence in BD-IX males exposed initially at either 120 or 210 days. Administration of androgen to castrate BD-IX males (120-day-old group) increases the incidence of colon cancer to that approaching the intact animal but has little effect in the BD-II castrate male. These data suggest a genetically influenced susceptibility to DMH-induced colon carcinogenesis between BD-II and BD-IX rats. Furthermore, a sex difference is evident in both BD lines but age appears to be a factor only in older BD-IX females. Apparently, androgens influence DMH-induced tumorigenesis in BD-IX males only if the initial exposure of DMH occurs after sexual maturity.

背景与目标： : bd-ii和bd-ix雄性和雌性大鼠每周接受15 mg/kg 1,2-二甲基肼二盐酸盐 (DMH) 的皮下 (s.c.) 注射，从35、120或210日龄开始，持续20周。对照动物仅接受DMH运载工具。在21、106和196天时对三个年龄组的其他bd-ii和bd-ix雄性和雌性大鼠进行性腺切除。从性腺切除术后14天开始，大鼠接受了15 mg/kg的DMH。每周注射一次，持续20周。在最初的DMH注射后35周处死动物。适当年龄和性别的对照大鼠没有发展为结肠肿瘤。Bd-ix大鼠显然比bd-ii大鼠对DMH更敏感。在bd-ii和bd-ix动物中，女性中DMH诱发的癌症的发生率均低于男性。性腺切除术不影响bd-ii男性或女性或bd-ix女性的癌症发病率，但降低了最初在120天或210天暴露的bd-ix男性的发病率。对去势的bd-ix雄性 (120天大组) 施用雄激素可增加结肠癌的发生率，使其接近完整动物，但对bd-ii去势的雄性几乎没有影响。这些数据表明，在BD-II和BD-IX大鼠之间，对DMH诱导的结肠癌发生的遗传易感性受到影响。此外，两个BD系的性别差异都很明显，但年龄似乎仅是年龄较大的bd-ix女性的一个因素。显然，只有当DMH的初次暴露发生在性成熟后，雄激素才会影响bd-ix男性中DMH诱导的肿瘤发生。

BACKGROUND & AIMS: :Vitamin D is suggested to have a role in the coupling of bone resorption and formation. Compared with women, men are believed to have more stable bone remodeling, and thus, are considered less susceptible to the seasonal variation of calcitropic hormones. We examined whether seasonal variation exists in calcitropic hormones, bone remodeling markers, and BMD in healthy men. Furthermore, we determined which vitamin D intake is required to prevent this variation. Subjects (N = 48) were healthy white men 21-49 yr of age from the Helsinki area with a mean habitual dietary intake of vitamin D of 6.6 +/- 5.1 (SD) microg/d. This was a 6-mo double-blinded vitamin D intervention study, in which subjects were allocated to three groups of 20 microg (800 IU), 10 microg (400 IU), or placebo. Fasting blood samplings were collected six times for analyses of serum (S-)25(OH)D, iPTH, bone-specific alkaline phosphatase (BALP), and TRACP. Radial volumetric BMD (vBMD) was measured at the beginning and end of the study with pQCT. Wintertime variation was noted in S-25(OH)D, S-PTH, and S-TRACP (p < 0.001, p = 0.012, and p < 0.05, respectively) but not in S-BALP or vBMD in the placebo group. Supplementation inhibited the winter elevation of PTH (p = 0.035), decreased the S-BALP concentration (p < 0.05), but benefited cortical BMD (p = 0.09) only slightly. Healthy men are exposed to wintertime decrease in vitamin D status that impacts PTH concentration. Vitamin D supplementation improved vitamin D status and inhibited the winter elevation of PTH and also decreased BALP concentration. The ratio of TRACP to BALP shows the coupling of bone remodeling in a robust way. A stable ratio was observed among those retaining a stable PTH throughout the study. A daily intake of vitamin D in the range of 17.5-20 microg (700-800 IU) seems to be required to prevent winter seasonal increases in PTH and maintain stable bone turnover in young, healthy white men.

背景与目标： : 建议维生素d在骨吸收和形成的耦合中起作用。与女性相比，男性被认为具有更稳定的骨骼重塑，因此被认为不太容易受到钙调激素的季节性变化的影响。我们检查了健康男性的钙蛋白激素，骨重塑标志物和BMD是否存在季节性变化。此外，我们确定了需要摄入哪种维生素d来防止这种变化。受试者 (N = 48) 是来自赫尔辛基地区的21-49岁健康白人，平均习惯性饮食摄入的维生素d为6.6/- 5.1 (SD) microg/D。这是一项6个月的双盲维生素d干预研究，其中将受试者分配到三组20微克 (800 IU)，10微克 (400 IU) 或安慰剂。空腹采血六次，以分析血清 (S-)25(OH)D，iPTH，骨特异性碱性磷酸酶 (BALP)，和TRACP。在研究开始和结束时用pQCT测量径向体积BMD (vBMD)。在S-25(OH)D、S-PTH和S-TRACP中观察到冬季变化 (p <0.001，p = 0.012和p <0.05，但在安慰剂组的S-BALP或vBMD中没有。补充抑制冬季PTH升高 (p = 0.035)，降低S-BALP浓度 (p <0.05)，但对皮质骨密度 (p = 0.09) 仅略有益处。健康男性暴露于影响PTH浓度的维生素d状态的冬季降低。补充维生素d改善了维生素d状态，抑制了PTH的冬季升高，也降低了BALP浓度。TRACP与BALP的比率显示了骨重塑的耦合以一种稳健的方式。在整个研究中，在保持稳定的PTH的人群中观察到稳定的比例。每天摄入17.5-20微克 (700-800 IU) 的维生素d似乎需要防止冬季PTH季节性增加，并保持年轻时的稳定骨转换，健康的白人。

BACKGROUND & AIMS: :We investigated how visitor-use affects water quality in wilderness in Yosemite National Park. During the summers of 2012-2014, we collected and analyzed surface-water samples for water-quality indicators, including fecal indicator bacteria Escherichia coli, nutrients (nitrogen, phosphorus, carbon), suspended sediment concentration, pharmaceuticals, and hormones. Samples were collected upstream and downstream from different types of visitor use at weekly to biweekly intervals and during summer storms. We conducted a park-wide synoptic sampling campaign during summer 2014, and sampled upstream and downstream from meadows to evaluate the mitigating effect of meadows on water quality. At pack stock stream crossings, Escherichia coli concentrations were greater downstream from crossings than upstream (median downstream increase in Escherichia coli of three colony forming units 100 mL-1), with the greatest increases occurring during storms (median downstream increase in Escherichia coli of 32 CFU 100 mL-1). At backpacker use sites, hormones, and pharmaceuticals (e.g., insect repellent) were detected at downstream sites, and Escherichia coli concentrations were greater at downstream sites (median downstream increase in Escherichia coli of 1 CFU 100 mL-1). Differences in water quality downstream vs. upstream from meadows grazed by pack stock were not detectable for most water-quality indicators, however, Escherichia coli concentrations decreased downstream, suggesting entrapment and die-off of fecal indicator bacteria in meadows. Our results indicate that under current-use levels pack stock trail use and backpacker use are associated with detectable, but relatively minor, effects on water quality, which are most pronounced during storms.

背景与目标： : 我们调查了游客的使用如何影响优胜美地国家公园荒野中的水质。在2012-2014年夏季，我们收集并分析了地表水样品的水质指标，包括粪便指示细菌大肠杆菌，营养物质 (氮，磷，碳)，悬浮沉积物浓度，药物和激素。在每周至每两周的间隔以及夏季风暴期间，从不同类型的访客使用的上游和下游收集样本。我们在夏季2014进行了公园范围的天气采样活动，并从草甸的上游和下游采样，以评估草甸对水质的缓解作用。在pack种群流过境处，从过境处下游的大肠杆菌浓度高于上游 (三个菌落形成单位100   mL-1的大肠杆菌的下游中位值增加)，其中最大的增加发生在风暴期间 (大肠杆菌的下游中位值增加32 CFU 100   mL-1)。在背包客使用地点，在下游地点检测到激素和药物 (例如，驱虫剂)，并且在下游地点检测到大肠杆菌浓度更高 (大肠杆菌的下游增加中位数为1 CFU 100 mL-1)。对于大多数水质指标，无法检测到填鸭式草甸下游与上游的水质差异，但是，下游的大肠杆菌浓度降低，表明草甸中粪便指示细菌的截留和死亡。我们的结果表明，在当前使用水平下，包装库存的使用和背包客的使用与可检测但相对较小的水质影响有关，这在暴风雨期间最为明显。

BACKGROUND & AIMS: :The presence of "high-affinity-saturable" binding sites for thyroid hormones of similar characteristics not only in isolated nuclei but in all the major extranuclear cellular components, as well as the failure of cytosol to promote nuclear binding, invalidates the analogy with steroid hormone receptors and necessitates a more critical assessment of the physiological relevance of current approaches to binding of thyroid hormone in vitro nuclear preparations.

背景与目标： : 不仅在孤立的细胞核中，而且在所有主要的核外细胞成分中都存在具有相似特征的甲状腺激素的 “高亲和力饱和” 结合位点，以及细胞质不能促进核结合，使与类固醇激素受体的类比无效，并且需要对当前与体外核制剂中甲状腺激素结合的方法的生理相关性进行更严格的评估。

BACKGROUND & AIMS: :Advanced cancers are associated with a chronic inflammation, especially high interleukin-6 (IL-6) and with various levels of adipokines (leptin and adiponectin), while ghrelin counteracts the anorexigenic effect of leptin in cancer-induced anorexia-cachexia syndrome. We aimed to understand how IL-6, adipokines and ghrelin plasma levels could be influenced by cancer on the one hand, and by age, frailty, and nutritional status in old cancer patients on the other hand. Ninety-nine patients aged 79[76-83] years old were included. Sixty-six percent had advanced stages of cancer, and 34% had cachexia. Fifty percent were at risk of malnutrition, and 10% had overt malnutrition. None of the variables studied was significantly correlated with the advanced stage, or cachexia. In multiple regression, the only parameter significantly and positively associated with age was adiponectin (p = 0.008). Despite a high prevalence of frailty in our study, we did not find any independent association of frailty (assessed by G8) with IL-6, leptin, adiponectin, or ghrelin in multivariate analysis. We observed that a low albumin level was independently associated with a higher level of IL-6 (p < 0.0001), but not with the MNA score. However, leptin showed a positive correlation with BMI (p < 0.0001), confirming the persistence of a relationship between leptin and adiposity, even in older cancer patients. Finally, high IL-6 level was associated with a higher mortality rate (p = 0.027). In conclusion, IL-6, leptin, adiponectin, and ghrelin are not associated with advanced stages of cancer or cancer-induced cachexia in older subjects with cancer, but they are significantly correlated with anthropometric factors and body composition.

背景与目标： : 晚期癌症与慢性炎症有关，尤其是高interleukin-6 (IL-6) 和各种水平的脂肪因子 (瘦素和脂联素)，而ghrelin抵消了瘦素在癌症引起的厌食-恶病菌综合征中的厌食作用。我们旨在了解IL-6，脂肪因子和ghrelin血浆水平如何一方面受到癌症的影响，另一方面又受到老年癌症患者的年龄，虚弱和营养状况的影响。包括99名79岁 [76-83] 岁的患者。60 6% 人患有晚期癌症，34% 人患有恶病菌。50% 的人有营养不良的风险，10% 有明显的营养不良。研究的变量均未与晚期或恶食症显着相关。在多元回归中，与年龄显著正相关的唯一参数是脂联素 (p = 0.008)。尽管我们的研究中脆弱的患病率很高，但在多变量分析中，我们没有发现脆弱 (通过G8评估) 与IL-6，瘦素，脂联素或ghrelin有任何独立关联。我们观察到低白蛋白水平与较高水平的IL-6独立相关 (p <0.0001)，但与MNA评分无关。然而，瘦素与BMI呈正相关 (p <0.0001)，证实了瘦素与肥胖之间的关系的持久性，即使在老年癌症患者中也是如此。最后，高IL-6水平与较高的死亡率相关 (p = 0.027)。总之，在老年癌症患者中，IL-6，瘦素，脂联素和ghrelin与癌症的晚期或癌症诱发的恶病菌无关，但它们与人体测量因素和身体组成显着相关。

BACKGROUND & AIMS: :Melanophore-stimulating hormones (MSHs) from chum salmon cause pigment dispersion in isolated melanophores of medaka, a teleost. The in vitro medaka melanophore bioassay that responded to light with pigment dispersion and to the dark with pigment aggregation was utilized for measuring the activity of melanotropic hormones. alpha-MSH I was the most potent melanophore-dispersing agent tested. The minimal dose for the induction of pigment dispersion was 10(-15) M alpha-MSH I, 10(-13) M N-des-acetyl(Ac)-alpha-MSH, and 10(-11) M beta-MSH I, respectively. The melanosome-dispersing activity of beta-MSH I was enhanced about 40% by salmon N-acetyl-endorphin I (N-Ac-EP). The results suggest that N-Ac-EP may act as an enhancer for the activity of certain MSHs. The present bioassay provides a unique method for determining the biological activity of melanotropic peptides.

背景与目标： : 来自大麻哈鱼的黑色素刺激激素 (MSHs) 导致色素分散在medaka (一种硬骨鱼) 的分离黑色素中。体外的medaka黑色素团生物测定法可对色素分散液的光和对色素聚集的黑暗产生反应，用于测量促黑素激素的活性。alpha-MSH I是测试的最有效的黑色素分散剂。诱导色素分散的最小剂量分别为10(-15) M α-MSH I、10(-13) M N-去乙酰基 (Ac)-α-MSH和10(-11) M β-MSH I。鲑鱼N-乙酰内啡肽I (N-Ac-EP) 增强了 β-MSH I的黑素体分散活性约40%。结果表明，n-ac-ep可能是某些MSHs活性的增强剂。本生物测定法提供了一种用于确定促黑肽的生物活性的独特方法。

BACKGROUND & AIMS: :Metabolic processes are affected by both temperature and thyroid hormones in ectothermic vertebrates. Temperature is the major determinant of incubation length in oviparous vertebrates, but turtles can also alter developmental rate independent of temperature. Temperature gradients within natural nests cause different developmental rates of turtle embryos within nests. Despite temperature-induced reductions in developmental rate, cooler-incubated neonates often hatch synchronously with warmer siblings via metabolic compensation. The physiological mechanisms underlying metabolic compensation are unknown, but thyroid hormones may play a critical role. We applied excess triiodothyronine (T3) to developing eggs of Murray River short-necked turtle (Emydura macquarii)-a species that exhibits metabolic compensation and synchronous hatching-to determine whether T3 influences developmental rate and whether changes to incubation period incur metabolic costs. We measured heart rate, oxygen consumption and incubation period of eggs, and morphology and performance of hatchlings. Embryos that were exposed to T3 pipped up to 3.5 d earlier than untreated controls, despite no change in total metabolic expenditure, and there were no treatment differences in hatchling morphology. Hatchlings treated with T3 demonstrated similar righting ability to hatchlings from the control groups. Exposure to T3 shortens incubation length by accelerating embryonic development but without statistically increasing embryonic metabolism. Thus, T3 is a mechanism that cooler-incubated reptiles could use to accelerate their development to allow synchronous hatching with their warmer clutch mates but at little or no metabolic cost. Thus, metabolic compensation for synchronous hatching may not be metabolically expensive if T3 is the underlying mechanism.

背景与目标： : 代谢过程受体温和甲状腺激素的影响。温度是卵生脊椎动物孵化长度的主要决定因素，但海龟也可以独立于温度改变发育速率。自然巢内的温度梯度会导致巢内海龟胚胎的发育速率不同。尽管温度引起的发育速率降低，但低温孵育的新生儿通常通过代谢补偿与温暖的兄弟姐妹同步孵化。代谢补偿的生理机制尚不清楚，但甲状腺激素可能起着关键作用。我们将过量的三碘甲腺原氨酸 (T3) 应用于默里河短颈龟 (Emydura macquarii) 的发育卵 (一种具有代谢补偿和同步孵化的物种)，以确定T3是否影响发育速率以及潜伏期的变化是否会产生代谢成本。我们测量了心率，耗氧量和卵的潜伏期，以及幼体的形态和性能。尽管总代谢消耗没有变化，并且孵化形态也没有处理差异，但暴露于T3的胚胎比未处理的对照早3.5 d。用T3处理的幼体表现出与对照组的幼体相似的扶正能力。暴露于T3会通过加速胚胎发育而缩短孵育时间，但不会在统计学上增加胚胎代谢。因此，T3是一种机制，可以用较冷的爬行动物来加速其发育，以允许与较热的离合器伴侣同步孵化，但几乎没有代谢成本。因此，如果T3是潜在的机制，则同步孵化的代谢补偿可能在代谢上并不昂贵。

BACKGROUND & AIMS: :The aim of this study was to examine the effect of high-intensity sprint and strength training (HISST) on glucoregulatory hormones in young (20 years) and middle-aged (40 years) men. Thirty-six moderately trained men participated as volunteers in this study. After medical examination, eligible subjects were randomly assigned to one of four groups according to their age: a young training group (21.3 ± 1.3 yrs, YT, n = 9), a young control group (21.4 ± 1.7 yrs, YC, n = 9), a middle-aged training group (40.7 ± 1.8 yrs, AT, n = 9), and a middle-aged control group (40.5 ± 1.8 yrs, AC, n = 9). YT and AT participated in HISST for 13 weeks. Before and after HISST, all participants performed the Wingate Anaerobic Test (WAnT). Blood samples were collected at rest, after warm-up (50% VO2max), immediately post-WAnT, and 10 min post-WAnT. Before HISST, we observed significantly higher (P < 0.05) glucose concentrations in AT (5.86 ± 0.32 mmol.L-1) compared to YT (4.24 ± 0.79 mmol.L-1) at rest, and in response to WAnT (6.56 ± 0.63 mmol.L-1 vs. 5.33 ± 0.81 mmol.L-1). Cortisol levels were significantly higher (P < 0.05) in AT than in YT in response to WAnT (468 ± 99.50 ng.mL-1 vs. 382 ± 64.34 ng.mL-1). Catecholamine levels measured at rest and in response to WAnT rose in a similar fashion. After HISST, this "age effect" disappeared at rest and in response to exercise in the trained groups (YT and AT). Changes in hormone concentrations with intense training are due to adaptive changes in various tissues, especially in the skeletal muscle and liver in trained subjects. HISST may, at least in part, counteract the negative "age effect" on glucose metabolism.

背景与目标： : 这项研究的目的是研究高强度冲刺和力量训练 (HISST) 对年轻 (20岁) 和中年 (40岁) 男性的糖调节激素的影响。36名受过中等训练的男性作为志愿者参加了这项研究。体检后，符合条件的受试者根据年龄随机分为四组之一: 青年训练组 (21.3   ±   1.3岁，YT，n   =   9)，青年对照组 (21.4   ±   1.7岁，YC，n   =   9)，中年训练组 (40.7   ±   1.8岁，AT，n   =   9)，中年对照组 (40.5   ±   1.8岁，AC，n   =   9)。YT和AT参加了HISST 13周。在HISST之前和之后，所有参与者都进行了Wingate厌氧测试 (WAnT)。在休息时，预热后 (50% VO2max)，想要后立即和想要后10  min收集血样。在HISST之前，我们观察到AT (5.86   ±   0.32 mmol.L-1) 的葡萄糖浓度明显高于静止时的YT (4.24   ±   0.79 mmol.L-1)，并响应于WAnT (6.56   ±   0.63 mmol.L-1 vs. 5.33   ±   0.81 mmol.L-1)。在WAnT反应中，AT的皮质醇水平显著高于YT (p  <  0.05) (468   ±   99.50 ng ng.mL-1 vs. 382   ±   64.34 ng ng.mL-1)。在休息和WAnT反应中，儿茶酚胺水平以类似的方式上升。在HISST之后，这种 “年龄效应” 在休息和训练组 (YT和at) 的运动中消失了。剧烈训练时激素浓度的变化是由于各种组织的适应性变化，尤其是训练有素的受试者的骨骼肌和肝脏。HISST可能至少部分抵消了对葡萄糖代谢的负面 “年龄效应”。

BACKGROUND & AIMS: Context:We hypothesize that endogenous sex steroids are associated with fracture risk independent of race/ethnicity. Design and Setting:We performed a nested case-control study within the prospective Women's Health Initiative Observational Study. Incident nonspine fractures were identified in 381 black, 192 Hispanic, 112 Asian, and 46 Native American women over an average of 8.6 years. A random sample of 400 white women who experienced an incident fracture was chosen. One control was selected per case and matched on age, race/ethnicity, and blood draw date. Bioavailable estradiol (BioE2), bioavailable testosterone (BioT), and sex hormone-binding globulin (SHBG) were measured using baseline fasting serum. Conditional logistic regression models calculated the odds ratio (OR) and 95% confidence interval (CI) of fracture across tertiles of hormone. Results:In multivariable and race/ethnicity-adjusted models, higher BioE2 (>8.25 pg/mL) and higher BioT (>13.3 ng/dL) were associated with decreased risk of fracture (OR, 0.65; 95% CI, 0.50 to 0.85; P trend = 0.001 and OR, 0.76; 95% CI, 0.60 to 0.96; P trend = 0.02, respectively). The interaction term between race/ethnicity and either BioE2 or BioT was not significant. There was no association between SHBG and fracture risk. In models stratifying by race/ethnicity, higher BioE2 was associated with a lower risk of fracture in both white women (OR, 0.56; 95% CI, 0.36 to 0.87) and black women (OR, 0.61; 95% CI, 0.39 to 0.96). Higher BioT was associated with a significantly lower fracture risk in only black women (OR, 0.65; 95% CI, 0.43 to 1.00), P trend = 0.03. Conclusions:Serum BioE2 and BioT are associated with fracture risk in older women irrespective of race/ethnicity and independent of established risk factors for fracture.

背景与目标：

BACKGROUND & AIMS: :Largely attributable to concerns surrounding sustainability, the utilisation of omega-3 long-chain polyunsaturated fatty acid-rich (n-3 LC-PUFA) fish oils in aquafeeds for farmed fish species is an increasingly concerning issue. Therefore, strategies to maximise the deposition efficiency of these key health beneficial fatty acids are being investigated. The present study examined the effects of four vegetable-based dietary lipid sources (linseed, olive, palm and sunflower oil) on the deposition efficiency of n-3 LC-PUFA and the circulating blood plasma concentrations of the appetite-regulating hormones, leptin and ghrelin, during the grow-out and finishing phases in rainbow trout culture. Minimal detrimental effects were noted in fish performance; however, major modifications were apparent in tissue fatty acid compositions, which generally reflected that of the diet. These modifications diminished somewhat following the fish oil finishing phase, but longer-lasting effects remained evident. The fatty acid composition of the alternative oils was demonstrated to have a modulatory effect on the deposition efficiency of n-3 LC-PUFA and on the key endocrine hormones involved in appetite regulation, growth and feed intake during both the grow-out and finishing phases. In particular, n-6 PUFA (sunflower oil diet) appeared to 'spare' the catabolism of n-3 LC-PUFA and, as such, resulted in the highest retention of these fatty acids, ultimately highlighting new nutritional approaches to maximise the maintenance of the qualitative benefits of fish oils when they are used in feeds for aquaculture species.

背景与目标： : 很大程度上归因于对可持续性的担忧，在水产养殖鱼类中利用富含omega-3长链多不饱和脂肪酸 (n-3 LC-PUFA) 鱼油是一个越来越令人关注的问题。因此，正在研究使这些关键健康有益脂肪酸的沉积效率最大化的策略。本研究研究了四种基于蔬菜的膳食脂质来源 (亚麻籽，橄榄，棕榈油和葵花籽油) 对n-3 lc-pufa沉积效率以及食欲调节激素，瘦素和生长素的循环血浆浓度的影响，在虹鳟鱼养殖的生长和整理阶段。在鱼的表现中发现了最小的有害影响; 但是，组织脂肪酸组成中明显出现了重大变化，这通常反映了饮食的变化。在鱼油整理阶段之后，这些修饰有所减少，但持久的效果仍然很明显。已证明替代油的脂肪酸组成对n-3 lc-pufa的沉积效率以及在生长和精加工阶段参与食欲调节，生长和饲料摄入的关键内分泌激素具有调节作用。特别是，n-6 PUFA (葵花籽油饮食) 似乎 “消除” 了n-3 LC-PUFA的分解代谢，因此导致这些脂肪酸的最高保留，最终强调新的营养方法，以最大程度地维持鱼油在水产养殖物种饲料中使用时的质量效益。

BACKGROUND & AIMS: :Changes in the serum levels of gonadotrophins and steroid hormones with increasing age were studied in 449 women aged 40 and over to investigate the relationships between these hormones even very late in life. The levels of oestradiol (E2) and dehydroepiandrosterone sulphate (DHEA-S) fell after age 50 and remained low thereafter. However, while serum oestrone (E1), testosterone (T), delta-4-androstenedione (A) and prolactin (PRL) concentrations also decreased initially after age 50 they subsequently rose again progressively and this increase was in fact significant in the case of E1. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) rose after age 50, but whereas FSH remained elevated, LH decreased late in life. Cortisol (F) increased significantly after age 70. There was a significant correlation between androgens and E1 as well as between E2 and LH, even after age 60. Owing to the great heterogeneity of the population studied, it is not yet possible to speculate as to the physiopathological significance of these observations. It would seem, however, that the negative feedback effect of oestrogens on LH secretion remains operational very late in life.

背景与目标： : 在449名40岁及以上的女性中，研究了随着年龄增长而血清促性腺激素和类固醇激素水平的变化，以研究这些激素之间的关系，甚至在生命的晚期。50岁后，雌二醇 (E2) 和硫酸脱氢表雄酮 (dhea-s) 的水平下降，此后保持较低水平。然而，尽管血清雌酮 (E1)，睾丸激素 (T)，delta-4-androstenedione (A) 和催乳素 (PRL) 的浓度在50岁后也最初降低，但随后又逐渐升高，并且在E1的情况下，这种增加实际上是显着的。黄体生成素 (LH) 和卵泡刺激素 (FSH) 在50岁后上升，但FSH仍然升高，LH在生命后期下降。皮质醇 (F) 在70岁后显着增加。即使在60岁以后，雄激素与E1之间以及E2与LH之间也存在显着相关性。由于所研究人群的异质性很大，因此尚无法推测这些观察的生理病理意义。然而，似乎雌激素对LH分泌的负反馈作用在生命的后期仍然有效。