Influence of castration-induced testosterone and estradiol deficiency on obesity and glucose metabolism in male Göttingen minipigs

Low testosterone and estradiol concentrations are predictive for the development of the metabolic syndrome in men and women, respectively. The aim of this study was to investigate the influence of sex hormone deficiency on food intake, body weight, body composition and glucose metabolism in male Göttingen minipigs.Five adult male Göttingen minipigs were studied before castration (pre-cast), 10-18 days (post-cast 1) and 10-11 weeks (post-cast 2) after castration. Parameters of interest were food intake, body weight, body fat percentage and sex hormone concentrations. Furthermore glucose tolerance, glucagon suppression, insulin resistance, beta cell function and disposition index were evaluated by oral and intravenous glucose tolerance tests.Castration led to almost complete disappearance of circulating testosterone and estradiol and secondarily to increased food intake, body weight and body fat percentage. Ten-eighteen days sex hormone deficiency (post-cast 1) did not significantly change any of the investigated metabolic parameters compared to pre-cast levels. Ten weeks after castration (post-cast 2) significant insulin resistance, glucose intolerance and hyperglucagonemia was found, and the beta cell function and the disposition index both were decreased.In conclusion, castration-induced sex hormone deficiency in male Göttingen minipigs results in hyperphagia, obesity and disturbed glucose metabolism, which are some of the features typical for the human metabolic syndrome.     

不同种源桃金娘表型性状多样性研究

为解析桃金娘表型性状多样性及其种源间关系，该文以20个不同来源的桃金娘为研究对象，在同质园栽培条件下，对其营养器官和花器官表型性状进行观测，采用方差分析、变异分析、Shannon-Wiener多样性指数分析和聚类分析等方法，探讨不同种源桃金娘表型性状多样性。结果表明：(1)不同种源桃金娘表型性状存在显著差异(P<0.05),Shannon-Wiener多样性指数均值在1.35以上，表型性状多样性丰富。(2)种源内表型性状变异系数均值在10.81%～63.75%之间，种源间的变异系数均值在13.08%～74.04%之间，种源间变异(23.33%)高于种源内变异(19.79%),营养器官变异(29.52%)高于花器官变异(14.06%)。(3)部分性状存在极显著或显著相关性，株高与分枝数呈极显著负相关，而与叶长、叶宽和叶面积等却呈显著正相关。(4)在欧式距离10处，20个种源桃金娘可分为A、B、C三类，A类包含8个种源，该类种源表现为植株高大、分枝少、叶大和花大等特征；B类包含11个种源，该类种源表现为株高中等、叶较大和花中等等特征；C类仅包含1个种源，表现为植株低矮、分枝多、叶小和...     

Developmental instability: measures of resistance and resilience using pumpkin (Cucurbita pepo L.)

Fluctuating asymmetry measures random deviations from bilateral symmetry, and thus estimates developmental instability, the loss of ability by an organism to regulate its development. There have been few rigorous tests of this proposition. Regulation of bilateral symmetry must involve either feedback between the sides or independent regulation toward a symmetric set point. Either kind of regulation should decrease asymmetry over time, but only right–left feedback produces compensatory growth across sides, seen as antipersistent growth following perturbation. Here, we describe the developmental trajectories of perturbed and unperturbed leaves of pumpkin, Cucurbita pepo L., grown at three densities. Covering one side of a leaf with aluminium foil for 24 h perturbed leaf growth. Reduced growth on the perturbed side caused leaves to become more asymmetrical than unperturbed controls. After the treatment the size-corrected asymmetry decreased over time. In addition, rescaled range analysis showed that asymmetry was antipersistent rather than random, i.e. fluctuation in one direction was likely to be followed by fluctuations in the opposite direction. Development involves right–left feedback. This feedback reduced size-corrected asymmetry over time most strongly in the lowest density treatment suggesting that developmental instability results from a lack of resilience rather than resistance.   © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78, 27–41.     

Similarity Indices for Spatia I Ecological Data

We present a method for assessing similarity between species maps of presence and absence or abundance that emphasizes global features while ignoring minor local dissimilarities. The method arranges sites into small groups, or cliques, and allows controlled changes to be made within cliques to reduce the influence of local discrepancies. Resulting measures of similarity are visually more satisfactory than traditional indices. We show that the similarity indices are useful for model selection by comparing observed spatial patterns with those predicted by different fitted models. Examples are provided for spatial distributions of oribatid mites (Acari, Oribatei), woodlarks (Lullula arborea), and red deer (Cervus elaphus).     

Interaction of cationic <Emphasis Type="Italic">meso</Emphasis>-porphyrins with liposomes,mitochondria and erythrocytes

Two series of cationic porphyrins meso-(3N-methylpyridinium)phenylporphyrin (3P1, 3P2c, 3P2t, 3P3 and 3P4) and meso-(4N-methylpyridinium)phenylporphyrin (4P1, 4P2c, 4P2t, 4P3 and 4P4) were studied to obtain a comprehensive understanding of factors that influence the binding of cationic porphyrins to liposomes and mitochondria, as well as their photodynamic efficiencies in erythrocytes. Binding and photodynamic efficiency were found to be inversely proportional to the number of positively charged groups and directly proportional to n-octanol/water partition coefficients (log P_OW), except for the cis molecules 3P2c and 4P2c. In the cis molecules, binding and photodynamic efficiency were much higher than expected, indicating that specific interactions not accounted by log P_OW enhance photodynamic efficiency. The effect of mitochondrial transmembrane electrochemical potentials on cationic porphyrin binding constants was estimated to be as large as 15%, and may be useful to selectively target this organelle when promoting photodynamic therapy to induce apoptosis.     

Electronic spectra and fluorescence properties of multichromophoric sulfonylureas

The multichromophoric character of two sulfonylurea herbicides, SMT and BNS, has been investigated in its manifestations in the electronic absorption spectra and in some fluorescence properties through a combined experimental and theoretical approach. After a theoretical analysis of the most stable structures of these flexible systems, the UV absorption spectra of the two multichromophoric compounds have been analysed both experimentally and theoretically, and most transitions have been assigned to individual chromophores, also by comparison with four suitable reference compounds (5-8). Finally, some experimental information concerning the fluorescence spectra and quantum yields have been analysed with reference to the contributions from single fluorophores and the role of low-lying n → π^∗ states.     

中国大陆青冈分布区东缘大金山岛种群种子形态变异

在大陆青冈分布区东缘的大金山岛种群中按不同坡向取样,旨在揭示相对均一条件下青冈种子的形态变异及变异的来源,以从不同侧面研究环境对形态变异的作用。大金山岛种群青冈种子的长度、直径和重量分别为1.557±0.128cm、1.175±0.112cm、1.321±0.310g,处于青冈种子正常分布范围内。单颗种子的长度、直径符合正态分布,而重量则明显偏离正态分布。不同坡向青冈种子间差异很小,表明微地形的影响较小;种群变异的来源株内和株间约各占一半,说明种子表型具有一定的可塑性,主要由于种子处于植株不同部位的缘故。     

邢台西部山地种子植物区系地理研究

邢台西部山地位于河北太行山脉南段,共有野生种子植物93科、393属、823种。该区系地理成分复杂,具有明显的温带性质,也有一定的热带亲缘,中国特有种丰富。运用相似性系数,对该区与其它8个山地植物区系成分进行了比较分析。结果表明:邢台西部山地植物区系与太岳山和中条山区系相似性较高,与东灵山、小五台山、雾灵山和伏牛山的关系次之,与长白山和神农架的相似性较低。     

Influence of agitation and aeration on growth and antibiotic production by <Emphasis Type="Italic">Xenorhabdus nematophila</Emphasis>

The effect of agitation and aeration on the growth and antibiotic production by Xenorhabdus nematophila YL001 grown in batch cultures were investigated. Efficiency of aeration and agitation was evaluated through the oxygen mass transfer coefficient (K _L a). With increase in K _L a, the biomass and antibiotic activity increased. Activity units of antibiotic and dry cell weight were increased to 232 U ml⁻¹ and 19.58 g l⁻¹, respectively, productivity in cell and antibiotic was up more than 30% when K _L a increased from 115.9 h⁻¹ to 185.7 h⁻¹. During the exponential growth phase, DO concentration was zero, the oxygen supply was not sufficient. So, based on process analysis, a three-stage oxygen supply control strategy was used to improved the DO concentration above 30% by controlling the agitation speed and aeration rate. The dry cell weight and activity units of antibiotic were further increased to 24.22 g l⁻¹ and 249 U ml⁻¹, and were improved by 24.0% and 7.0%, compared with fermentation at a constant agitation speed and a constant aeration rate (300 rev min⁻¹, 2.5 l min⁻¹).     

ISSR标记在黑木耳单核体遗传分析中的应用

采用原生质体单核化和单孢分离法分别获得黑木耳Auricularia auricula栽培菌株新科5号两个亲本单核体（T1、T2）和33个F1代孢子单核体。从73条ISSR引物中筛选出13条可区分两个亲本单核体（T1、T2）的引物,对新科5号及F1代孢子单核体进行扩增,共扩增出70条带,其中63条在供试菌株间表现出多态性,多态位点百分率为90.0%。根据扩增结果采用软件NTsys2.10e计算菌株间的遗传相似系数并进行聚类分析,36个菌株间的遗传相似系数（GS值）的变化范围为0.2500～0.8382,其中T1和T2之间的GS值最小,遗传相似程度最低;F1代33个孢子单核体中24个与T1聚为一类,其余9个与T2聚为另一类,但并非严格按照交配型进行归类。试验表明黑木耳子实体上各个担子在减数分裂中染色体交换极具多样性,F1代孢子单核体表现出偏向其中一个亲本的现象,ISSR标记在黑木耳杂交育种中具有潜在的应用价值。