Evidence for sexy sons in European starlings (Sturnus vulgaris)

The sexy son hypothesis suggests that females obtain future fitness benefits from mating with polygynous males through the inheritance by their sons of traits contributing to mating success. We tested this hypothesis in the facultatively polygynous European starling (Sturnus vulgaris) in two ways. We first compared sons of monogynous and polygynous free-living males for their abilities in nest site acquisition and female-directed behaviors in controlled aviary tests. We then investigated eggs laid in monogynous and polygynous matings for concentrations of maternal steroid hormones that could affect behavioral differentiation of sons. Sons of polygynous fathers defended more nest boxes and produced more courtship song than sons of monogynous fathers. Mean concentrations of maternal androstenedione (A4), 5-dihydrotestosterone (DHT), testosterone (T), and 17-estradiol (E) in yolks were not affected by mating status. However, the within-clutch pattern of A₄ depended on mating status, with higher concentrations in last than in first eggs of clutches of monogynous but not polygynous matings. These results suggest that (1) sons may inherit from their fathers behavioral qualities for the successful acquisition of nest sites and attraction of mates; (2) differential exposure to maternal steroid hormones during development in the egg is unlikely the cause of the behavioral differences between adult sons of monogynous and polygynous fathers; and (3) females adjust the within-clutch pattern of androgen to mating status, possibly in response to the expected contribution of their mate to nestling care.     

新型溴代阻燃剂TBB和TBPH混合物对罗非鱼甲状腺激素和生理生化指标的影响

为了研究新型溴代阻燃剂FM550的生态风险,以罗非鱼为模式生物,配制添加不同浓度FM550(0、10、100和400ng·g~(-1))的饲料,将罗非鱼暴露56 d后,研究不同暴露剂量条件下FM550对罗非鱼甲状腺激素以及血清生理生化指标的影响。研究表明,经不同浓度的FM550暴露56 d后,罗非鱼的基础生长数据并无显著变化,但罗非鱼的甲状腺激素水平发生改变,具体表现为高剂量的FM550暴露可以使罗非鱼血清中的三碘甲状腺原氨酸(T3)、游离三碘甲状腺原氨酸(FT3)含量降低,四碘甲状腺原氨酸(T4)、游离四碘甲状腺原氨酸(FT4)含量升高。同时,FM550的暴露还可以导致罗非鱼的脂代谢改变,具体变化为血清总胆固醇(TC)、甘油三酯(TG)含量降低,高密度脂蛋白(HDL-C)含量升高,低密度脂蛋白(LDL-C)含量降低。不同剂量的FM550暴露对罗非鱼的全血生化指标并无影响。     

水环境中26种类固醇激素的分析方法研究

建立了固相萃取-超高效液相-串联质谱法同时测定水环境中26种类固醇激素的分析方法。明确了取样体积为500 m L,Cleanert PEP为富集柱,乙酸乙酯为洗脱剂,甲醇为溶剂进行提取操作。选择了正离子模式,以0. 1%甲酸/甲醇-水为流动相,负离子模式以0. 1%氨水/乙腈-水为流动相,试样经AcquityTMUPLC BEH C18色谱柱分离后,选用质谱检测模式进行定性、定量分析。通过方法验证,26种类固醇激素的方法检出限为0. 3～1. 5 ng/L,测定下限为1. 2～6. 0 ng/L,代表性样品测定结果的相对标准偏差为2. 6%～13. 7%(n=6),加标回收率为71. 2%～121%。该方法操作便捷,灵敏度高,精密度和准确度良好,可适用于水环境中多种痕量、超痕量类固醇激素的定性定量分析。     

Prenatal detection of X-linked ichthyosis by maternal serum screening for down syndrome

Maternal serum unconjugated oestriol (uE3) was measured in 15 375 pregnancies during 2 years of second-trimester risk assessment for Down syndrome using biochemical markers. Very low levels of uE3 (<0·1 MOM) were detected in 22 serum samples (0·14 per cent). Very low uE3 was associated with an adverse outcome in 13 pregnancies including fetal death and miscarriage (N=11), anencephaly (N=1), and Meckel—Gruber syndrome (N=1). Dry scales on the skin appeared in the first year of life in four boys. From dermatological diagnosis, prenatal uE3 levels, and pedigree analysis, it is concluded that at least 5 in approximately 7500 male births in the study population are affected by steroid sulphatase deficiency, which is the biochemical defect in X-linked ichthyosis. Very low uE3 levels in the second trimester are indicative of this disease in pregnancies with normal ultrasound findings.     

苦马豆素致糖基转移酶活性改变对小鼠生殖激素分泌的影响

苦马豆素是疯草主要有毒成分,抑制α-甘露糖苷酶的活性,引起N-聚糖加工过程失调。笔者课题组前期研究得出:苦马豆素致糖蛋白激素(促卵泡素和促黄体素)糖基化位点上糖链结构发生改变,引起促性腺激素功能发生改变。而苦马豆素中毒对家畜生殖激素分泌的调节机制尚不明确。苦马豆素腹腔注射对小鼠进行染毒,收集妊娠期和分娩期小鼠的血液、子宫和卵巢组织,检测糖基转移酶活性、生殖激素水平及其受体mRNA和类固醇限速酶蛋白质表达量。结果表明:在妊娠和分娩期,苦马豆素致子宫内膜固有层大量低聚糖蓄积,显著抑制N-聚糖加工过程关键糖基转移酶的活性(P0.05);染毒组小鼠血液的生殖激素包括促卵泡素(FSH)、促黄体素(LH)、雌激素(E2)和孕酮(P4)水平显著低于对照组(P0.05)。在整个妊娠周期,染毒组小鼠4种激素受体mRNA的表达量显著低于对照组(P0.05)。在妊娠后期,染毒组小鼠3-β羟基类固醇脱氢酶(3-βHSD)和芳香化酶(CYP19A1)蛋白表达量显著低于对照组(P0.05)。苦马豆素可使N-聚糖加工紊乱,引起促性腺激素分泌降低,进一步降低生殖激素受体和性类固醇激素限速酶的表达量,致使性类固醇激素分泌下降,导致生殖激素分泌紊乱,最终结果造成机体繁殖性能下降。     

Role of water chemistry on estrone removal by nanofiltration with the presence of hydrophobic acids

Hydrophobic acid organic matter (HpoA) extracted from treated effluent has been known to improve the rejection of steroid hormone estrone by reverse osmosis (RO) and nanofiltration (NF) membranes. In this study, the effects of solution chemistry (solution pH and ionic strength) on the estrone rejection by NF membrane with the presence of HpoA were systematically investigated. Crossflow nanofiltration experiments show that the presence of HpoA significantly improved estrone rejection at all pH and ionic strength levels investigated. It is consistently shown that the “enhancement effect” of HpoA on estrone rejection at neutral and alkaline pH is attributed to the binding of estrone by HpoA macromolecules via hydrogen bonding between phenolic functional groups in feed solutions, which leads to an increase in molecular weight and appearance of negative charge. The membrane exhibited the best performance in terms of estrone rejection at pH 10.4 (compared to pH 4 and pH 7) as a result of strengthening the electrostatic repulsion between estrone and membrane with the presence of HpoA. At neutral pH level, the ability of HpoA macromolecules to promote estrone rejection became stronger with increasing ionic strength due to their more extended conformation, which created more chances for the association between estrone and HpoA. The important conclusion of this study is that increasing solution pH and salinity can greatly intensify the “enhancement effect” of HpoA. These results can be important for NF application in direct/indirect potable water reuse.     

类固醇类内分泌干扰物羟基衍生化条件的优化

以N-甲基-N-三甲基硅基三氟乙酰胺(MSTFA)为衍生化试剂,采用气相色谱-质谱联用技术(GC-MS)系统研究了4种类固醇类内分泌干扰物雌酮(E1)、17β-雌二醇(E2)、雌三醇(E3)、17α-乙炔基雌二醇(EE2)的羟基衍生化,主要考察了MSTFA用量、衍生化温度、衍生化时间对类固醇类内分泌干扰物衍生化效果的影响以及衍生化产物的稳定性、标准曲线、仪器检出限等.结果表明:100μl浓度为0.01μg.μl-1的标准混合溶液,MSTFA的最佳用量为20μl;最佳衍生化条件为70℃下反应30min;衍生化产物的稳定性较好,在-20℃下放置48h,相对响应因子(RRF)基本没有降低;在优化的实验条件下,各待测物具有良好的线性相关性,E1和E2的仪器检出限为0.1pg.μl-1,EE2和E3的仪器检出限为1pg.μl-1.     

甾体雌激素废水中优势降解菌的分离及特性

从某避孕药生产厂污水处理站好氧池活性污泥中通过富集驯化,分离到一株降解甾体雌激素(3-甲氧基-17a羟基-1,3,5(10),8(9)-雌甾-4-烯,简称MHE)的细菌ZY3菌株.经形态及16SrDNA序列分析初步鉴定,该菌株属于Raoultella属(Raoultellasp.).经过对ZY3菌株以MHE为唯一碳源生长和降解特性的分析表明,ZY3菌株利用MHE生长的最适温度和pH值分别为35℃和10.0,72h内的最适降解浓度为10mg/L.加入营养物质麦芽糖和蛋白胨能促进菌株对底物的降解,在72h内降解率达到了87%和85%.     

Correlated evolution of male and female testosterone profiles in birds and its consequences

Circulating levels of testosterone in adults have mainly evolved as a consequence of selection on males for increased levels, while levels of circulating testosterone in females may be an indirect consequence of selection on males. A review of the literature revealed that intense directional selection for high levels of circulating testosterone in birds is likely to be mainly due to direct selection on males. A comparative study of testosterone levels in birds revealed a strong positive relationship between peak testosterone levels in adult females and peak levels in males. The slope of this relationship was significantly less than unity, implying that the testosterone levels in females have been reduced in species with high levels in males. An analysis of the order of evolutionary events suggested that peak concentration of testosterone in females changed after peak concentrations of testosterone in males. Females in colonial species of birds had significantly higher circulating peak testosterone levels compared to females of solitary species, and relative levels after controlling for the effects of peak levels in males were also larger, suggesting that any costs of high testosterone levels in females are particularly likely in colonial birds. Direct selection on male circulating testosterone levels may increase the costs that females incur from high testosterone titers. For example, high female levels may negatively affect ovulation and laying and may also affect the levels of testosterone that females deposit in their eggs and hence the exposure of pre- and post-hatching offspring to testosterone. This in turn may affect not only offspring behavior, but also offspring development and the trade-offs between growth, development of immune function, and behavior in offspring.     

BSA体系中2,4-D和阿特拉津对性激素的干扰机理

在2,4-D和阿特拉津以及天然性激素(雌二醇、睾酮)中加入牛血清白蛋白(BSA),通过紫外吸收峰的变化、温度与体系荧光强度的关系、以及计算扩散碰撞猝灭常数Kq等方法确定2,4-D和阿特拉津均可以发生类似天然性激素和BSA间的基态络合.并通过双倒数公式计算出各自二元体系的结合常数.2,4-D、阿特拉津、雌二醇、睾酮与BSA的结合常数(K)均在104数量级,可以认为2,4-D和阿特拉津具有与天然性激素相近的对BSA结合能力,并可通过竞争占据结合位点的方式干扰正常性激素与BSA的结合.