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21.
Pagona Lagiou Chung-Cheng Hsieh Evangelia Samoli Areti Lagiou Biao Xu Guo-Pei Yu Sagano Onoyama Lucy Chie Lars J. Vatten Hans-Olov Adami Dimitrios Trichopoulos Michelle A. Williams 《Annals of epidemiology》2013,23(11):669-673
PurposePlacental weight has been associated with mammographic pattern and coronary heart disease in the adult offspring, but the mechanisms are unknown. We evaluated the associations of maternal and cord blood hormones with placental weight in normal pregnancies.MethodsProspective study of 167 normal singleton pregnancies in Boston, USA and 256 in Shanghai, China. Maternal hormone levels at the 27th gestational week were available for all pregnancies. Cord blood measurements were available for 86 pregnancies in Boston and 104 in Shanghai. Pearson partial correlation coefficients of log-transformed hormone levels with placental weight were calculated.ResultsMaternal levels of estriol, testosterone, and progesterone (P < .05) were positively associated with placental weight. There was no such evidence for adiponectin, prolactin, and insulin-like growth factor (IGF)-I. Cord blood steroids tended to be inversely associated with placental weight, the results being statistically significant for testosterone (P < .05). There was a marginally significant positive association of cord blood IGF-I with placental weight. Reported results were adjusted for study center.ConclusionsPlacental weight appears to be positively correlated with maternal steroids. Its correlation with cord blood steroids, however, appears inverse, compatible with negative feedback mechanisms. There is also a suggestion for placental weight to be positively associated with cord blood IGF-I. 相似文献
22.
Progesterone and corticosterone are key modulators of the respiratory control system. While progesterone is widely recognized as an important respiratory stimulant in adult and newborn animals, much remains to be described regarding the underlying mechanisms. We review the potential implication of nuclear and membrane progesterone receptors in adults and in newborns. This raises intriguing questions regarding the contribution of progesterone as a protective factor against some respiratory control disorders during early life. We then discuss our current understanding of the central integration of stressful stimuli and the responses they elicit. The fact that this system interacts with the respiratory control system, either because both share some common neural pathways in the brainstem and hypothalamus, or because corticosterone directly modulates the function of the respiratory control network, is a fascinating field of research that has emerged over the past few years. Finally, we review the short- and long-term consequences of disruption of stress circuitry during postnatal development on these systems. 相似文献
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目的 评价手术创伤对老龄大鼠认知功能及海马铁调素和膜铁转运蛋白1(FP1)表达的影响.方法 健康老龄雄性SD大鼠100只,18月龄,体重400~ 500 g,采用随机数字表法,将其分为2组(n=50):对照组(C组)腹腔注射水合氯醛麻醉,但不进行手术;手术创伤组(ST组)腹腔注射水合氯醛麻醉后行改良性剖腹探查术30 min.于术后24h时随机取10只大鼠,行水迷宫实验,测定认知功能,持续6d,分别于水迷宫实验第1、3、5、7天时随机取10只大鼠处死,取脑,分离海马,采用PCR和Western blot法检测海马铁调素和FP1的表达.结果 与C组比较,ST组水迷宫实验第3、4、5天时大鼠逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少(P<0.05),各时点海马铁调素表达上调,FP1表达下调(P<0.05).结论 手术创伤可降低老龄大鼠认知功能,其机制可能与上调海马铁调素表达,下调FP1表达有关. 相似文献
25.
《The journal of sexual medicine》2017,14(5):747-757
BackgroundCyproterone acetate (CA) is an antiandrogenic progestin commonly used in adult transwomen to suppress endogenous androgens, often in combination with estrogens to induce feminization.AimTo assess the (side) effects and biochemical changes of CA alone and in combination with estrogens in adolescent trans-girls.MethodsThis study was a retrospective analysis of clinical and biochemical data from 27 trans-girls who presented at Tanner stage G4 and were treated with CA monotherapy for at least 6 months (mean = 12 months) and then in combination with incremental doses of estrogens (CA + E; mean = 16 months). Statistical analysis of data included paired or unpaired Student t-test or Wilcoxon signed-ranks or Mann-Whitney U-test as appropriate.OutcomesAnthropometrics, reported beneficial and side effects, safety parameters, and hormone levels.ResultsPhysical changes included decrease of facial and non-facial hair growth. One third showed breast development under CA (Tanner stages B2–B3), which increased to Tanner stages B3 and B4 in 66.7% and 9.5% respectively, during CA + E. Reported side effects during CA and CA + E were breast tenderness, emotionality, fatigue, and flushes. No relevant weight changes were observed. Main safety parameters showed the following changes. Hemoglobin and hematocrit decreased and liver enzymes transiently and modestly increased during CA. Triglycerides and cholesterol levels slightly decreased during CA but returned to baseline during CA + E; glucose metabolism was unaffected. Relevant hormonal changes included a decrease in gonadotropins during CA + E and in total and free testosterone levels throughout treatment. Prolactin levels increased during CA and were restored during CA + E.Clinical ImplicationsCA produced modest feminizing effects in trans-girls and therefore might be a valuable alternative in situations in which gonadotropin-releasing hormone analogues are not the treatment of choice and/or are not reimbursed.Strengths and LimitationsThis is the first study to report on the effects of CA in the treatment of trans-girls and one of the few to report on the use of estrogens in this population. Limitations are the modest sample size and the retrospective nature of this study.ConclusionTreatment with CA in late-pubertal trans-girls overall was safe and well tolerated and induced mild clinical and biochemical feminizing changes. Rapid further feminization was observed with incremental doses of E.Tack LJW, Heyse R, Craen M, et al. Consecutive Cyproterone Acetate and Estradiol Treatment in Late-Pubertal Transgender Female Adolescents. J Sex Med 2017;14:747–757. 相似文献
26.
目的 探讨肥胖与雌性幼龄SD大鼠与青春发育提前之间的相关性。方法 将10只雌性SD大鼠与6只雄性SD大鼠随机分为两组,分别为亲代模型组(雌鼠n=5,雄鼠n=3)、亲代对照组(雌鼠n=5,雄鼠n=3)。模型组以高脂饲料饲喂8周造模,对照组用普通大鼠饲料饲喂,8周后筛选体质量大于对照组20%的模型组亲代大鼠体进行交配,繁殖的雌性仔鼠设定为模型组仔鼠,亲代对照组大鼠繁殖的雌性仔鼠作为对照组仔鼠。模型组仔鼠造模方法与模型组亲代大鼠相同,均为同配方高脂饲料饲喂,21日龄断乳后饲喂5周,对照组仔鼠则用普通饲料饲喂5周。自21日龄起每日观察仔鼠阴门开启情况,阴门开启后每日均进行阴道涂片检查,观察动情周期,并称量体重;体长及腹围的测量每两周进行1次;两组实验仔鼠均在56日龄时结束实验,腹主动脉取血,检测两组幼鼠56日龄血清胆固醇(CH)、甘油三酯(TG)、血清卵泡刺激素(FSH)、促黄体生成素(LH)、雌二醇(E2)。实验结束后解剖56日龄仔鼠,取材子宫、卵巢,计算卵巢指数、子宫指数,子宫、卵巢做病理切片HE染色,计数卵巢最大横截面黄体个数和成熟卵个泡数。结果 ①56日龄造模结束,模型组幼鼠体重、腹围均高于对照组幼鼠,P<0.001;②模型组幼鼠血清TG、CH均高于对照组,P<0.001;③模型组幼鼠血清LH、E2浓度高于对照组幼鼠,P<0.001,血清FSH浓度低于对照组,P<0.001;④模型组幼鼠卵巢病理切片中最大横截面黄体计数较对照组多,P<0.001;成熟卵泡计数少于对照组,P<0.001;⑤Pearson相关性分析结果为:幼龄SD大鼠体质量与第一次动情间期、阴门开启时间两项指标呈成负相关,与血清LH、卵巢最大横截面切片黄体计数两项指标成正相关;幼龄SD大鼠腹围与第一次动情间期出现时间、阴门开启时间两项指标成负相关,与血清LH、卵巢最大横截面切片黄体计数两项指标成正相关。结论 幼龄SD大鼠青春发育评判指标与肥胖指标具有相关性,呈正相关。即具有肥胖特征的幼龄SD大鼠青春发育较之正常对照组幼鼠提前。 相似文献
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28.
The aim of this study was to determine whether photoperiod-induced changes in body and fat mass are accompanied by changes in leptin and corticosterone concentrations in collared lemmings. At weaning, eighty male lemmings were maintained in either long photoperiod (LD, n = 40 ) or short photoperiod (SD, n = 40 ). Ten weeks post-weaning lemmings were weighed and assigned to a secondary photoperiod that consisted of either remaining in the same photoperiod or being transferred to the alternate photoperiod (LD-LD, LD-SD, SD-SD, and SD-LD; n = 20 per group). Ten days post-switch, half the animals from each group were sacrificed. The remaining animals were sacrificed on day 21 post-switch. Blood was collected for determination of serum leptin and corticosterone, and carcasses were analyzed for body composition. LD-SD lemmings gained the most weight, whilst SD-LD lemmings lost weight. SD-LD lemmings had significantly lower leptin levels relative to fat mass than SD-SD lemmings. Corticosterone levels were higher in the SD-LD than SD-SD lemmings on both days 10 and 21. Levels were not significantly different between LD-LD and LD-SD lemmings; however by day 21 the levels were slightly lower in the LD-SD lemmings. Discussion. Lemmings showed seasonally appropriate body weight changes in response to the changing photoperiod. Weight loss was associated with higher corticosterone, and lower leptin levels adjusted for fat mass. Neither relative leptin levels, nor corticosterone levels changed significantly with weight gain. Our results indicate that corticosterone and leptin are associated more with seasonal weight loss than weight gain in lemmings. 相似文献
29.
David M. Wilson III John J. Tentler James P. Carney Teresa M. Wilson Mark R. Kelley 《Alcoholism, clinical and experimental research》1994,18(5):1267-1271
Alcohol has clearly been associated with an increase of cancers in numerous tissues, including the respiratory tract, colon, rectum, liver, but especially the esophagus, larynx, pharynx, and mouth. Alcohol alone has not been shown to be a mutagen until it is converted to acetaldehyde and, therefore, alcohol presumably acts as a cocarcinogen. Previous data has shown that alcohol concentrations of 2% or greater inhibits DNA repair, and in light of the widespread consumption of alcoholic beverages with alcohol contents ranging from 4 to 5% (beer and wine coolers) to 50% (whiskey), interest in determining the mechanism(s) responsible for alcohol-induced carcinogenesis has heightened. Although previous studies, in intact rats, have investigated the effects of chronic alcohol exposure on some aspects of DNA repair, we have begun to address the effects of acute or "binge" alcohol exposure on mammalian DNA repair. Toward this end, we report the inhibition of O6 -methylguanine-DNA methyltransferase (MGMT) by a single intraperitoneal injection of 30% ethanol in adult male castrated rats. This inhibition lasted for at least 24 hr. We also observed a dose-response effect of ethanol on MGMT activity, again only in the castrated rats. The finding of ethanol's effect on MGMT activity in castrated and not intact rats implies a hormonal component of MGMT DNA repair response, which has only been alluded to in past research. 相似文献
30.
Thoracic endometriosis has been considered a rare clinical condition but it is probably underestimated in the literature. Various clinical symptoms may occur but the most frequent are catamenial pneumothoraces. Four main clinical conditions may reveal thoracic endometriosis: catamenial pneumothorax, catamenial haemothorax, catamenial haemoptysis and endometrial nodules in the lung. Catamenial pneumothoraces are the most frequent manifestation, characterized, in the majority of the cases, by right side localization and diaphragmatic abnormalities (perforations and/or nodules). The resection of suspected areas of visceral or parietal pleural endometriosis, as well as partial resection of the diaphragm in the case of nodules and/or perforations, allows the histological diagnosis of endometriosis. Because of the high recurrence rate, treatment of catamenial pneumothoraces should combine surgery and hormonal therapy. 相似文献