光周期和温度对布氏田鼠产热的影响

布氏田鼠（Ｍｉｃｒｏｔｕｓ ｂｒａｎｄｔｉ）分组驯化在：（１）长光照温暖环境（ＬＷ，１６Ｌ：８Ｄ，２５℃）；（２）长光照 低温环境（ＬＣ，１６Ｌ：８Ｄ，５℃）；（３）短光照温暖环境（ＳＷ，８Ｌ：１６Ｄ，２５℃）；（４）短光照低温环境（ＳＣ， ８Ｌ：１６Ｄ，５℃）。驯化四周后，长光照动物的体重比短光动物的体重有增加的趋势；四组动物的体温 没有明显差异；低温和短光照均促使静止代谢率（ＲＭＲ）增加；ＳＣ组动物的非颤抖性产热（ＮＳＴ）高 于ＬＷ组。低温诱导肝和褐色脂肪组织（ＢＡＴ）细胞线粒体蛋白增加，短光照再度地增强此作用。短 光照诱导肝细胞线粒体状态－４及状态－３呼吸活力增加，低温没有明显作用。低温和短光照均刺激肝 和ＢＡＴ线粒体细胞色素Ｃ氧化酶活力提高，但后者作用强度大于前者。低温明显激活ＢＡＴ线粒体 的ａ－磷酸甘油氧化酶的活力，短光照无明显影响、结果表明：低温和短光照均能提高布氏田鼠的产 热能力，短光照与低温因子两者的协同作用增强了对布氏四鼠热能代谢的调节。     

光照和温度对高原鼠逸褐色脂肪组织产热特征的影响

测定了高原鼠兔在驯化２周后褐色脂肪组织的蛋白含量,线粒体蛋白含量和细胞色素ｃ氧化酶活性的变化。结果表明,低温或短光照可刺激这些指标的增加;最高值出现在低温加短光照组。说明在季节性驯化过程中,光照和温度协同作用,以诱导动物的产热调节。     

光周期对粘虫生殖与飞翔影响的初步研究

在室内恒温条件下,测定了粘虫在短光照（ＬＤ８：１６）、中等光照（ＬＤ１２：１２）、长光照（ＬＤ１６：８）、光照逐日由长变短（ＬＤ１６：８－１２：１２）和逐日由为长（ＬＤ８：１６－１２：１２）等不同光周期条件下的发育进度,生殖力和飞翔能力。结果表明,光照由长变短使幼虫发育进度比其它处理平均缩短１ｄ以上,短光照、长变知道工换短、中等光照等条件下的成虫产卵前期均比长光照。短换长和短变和等处理蛾显著延长,     

高原鼠兔季节性繁殖中的神经内分泌调控Ⅱ．不同光制对生殖恢复期的影响

本项研究将野外捕获的成年雄性高原鼠兔（Ｏｃｈｏｔｏｎａｃｕｒｚｏｎｉａｅ）分３组进行不同光制的饲养,以检验光周期对其神经内分泌─—生殖轴功能的影响：（１）长光照组睾丸及附属性腺的重量和血浆睾酮水平均明显高于自然光组（ｐ＜０．０５）和短光照组（ｐ＜０．０１）。（２）长光照组的松果腺重量（１．５±０．１毫克,ｎ＝１５）和褪黑激素含量（８９．７±５．８微微克／松果腺）,均显著低于其它两组。（３）自然光组和短光照组性腺的显著萌发表明,在高原鼠兔季节性繁殖的年周期中,其神经内分泌─—生殖轴对春分前短光照的抑制作用具有不应期。     

光照周期对叙利亚地鼠生长发育和繁殖的影响

对离乳雄性叙利亚地鼠（Ｍｅｓｏｃｒｉｃｅｔｕｓａｕｒａｔｕｓ）和雌性叙利亚地鼠各３０只分别给以长光照（１６Ｌ：８Ｄ）、中光照（１２Ｌ：１２Ｄ）和短光照（８Ｌ：１６Ｄ）三种光周期处理,研究光周期对叙利亚地鼠生长发育和繁殖的影响。１３周龄时,短光照处理组雄性地鼠的体重显著（Ｐ＜０．０５）高于长光照和中光照组的体重;雌性地鼠９周龄时长光照组的体重显著（Ｐ＜０．０１）高于另外两个处理组的体重,较高的日食量可能是长光照组具有较大体重的原因之一,雄性地鼠的睾丸、副睾和肾上腺重量及雌性地鼠的卵巢、子宫和肾上腺重量表现了随着光照时间的延长而递增的趋势。长光照条件有利于雌性地鼠的正常发情和繁殖。每天１６ｈ的光照对繁殖地鼠是比较适宜的。     

高原鼠冬季节性繁殖中的神经内分泌调控：Ⅱ.不同光制对光殖恢复的…

本项针野外捕获的成年雄性高原鼠兔分３组进行不同光制的饲养,以检验光周期对其神经内分泌－－生殖轴功能的影响：（１）长光照组睾丸及附属性腺的重量和血浆睾酮水平均明显高于自然光组（Ｐ＜０．０５）和短光照组（Ｐ＜０．０１）。（２）长光照组的松果腺重量（１．５±０．１毫克,ｎ＝１５）和褪黑激素含量（８９．７±５．８微微克／松果腺）,均显著低于其它两组。（３）自然兴和短光照组性腺的显著萌发表明,在高原鼠兔节性     

高原鼠兔季节性繁殖中的神经内分泌调控Ⅰ.在性休止期不同光制的影响

本文研究了处于性休止期的雄性高原鼠兔在不同光周期饲养后体重和性腺重量的变化,同时 对其血浆睾酮水平和松果腺褪黑激素含量的变化进行分析：１）无论在长日照、自然光照、或是短 日照条件,高原鼠兔的体重无明显差异（Ｐ＞０. ０５）;２）长日照组鼠兔的睾丸、附睾、输精管和精 囊腺远重于自然光照组（Ｐ＜０．００１）和短日照组（Ｐ＜０．００１）;３）长日照组鼠兔血浆睾酮的含量 明显高于自然光照组（Ｐ＜０．００１）和短日照组（Ｐ＜０．００１）;４）长日照组鼠兔松果腺褪黑激素含 量远低于自然光照组（Ｐ＜０．００１）和短日照组（Ｐ＜０．００１）。结果表明：高原鼠兔是长日照动物。     

高原鼠兔季节性繁殖中的神经内分泌调控：Ⅰ.在性休止期不同光制的…

本文研究了处于性休止期的雄性高原鼠兔在不同光周期饲养后体重和性腺重量的变化,同时对其血浆睾酮水平和松果腺褪黑激素含量的变化进行分析：１）无论在长日照、自然光照、或是短日照条件,高原鼠兔的体重无明显差异（Ｐ＞０．０５）;２）长日照组鼠兔的睾丸,附睾,输精管和精囊腺远重于自然光照组（Ｐ＜０．００１）和短日照组（Ｐ＜０．００１）;３）长日照组鼠兔血浆睾酮的含量明显高于自然光照组（Ｐ＞０．００１）和短日照     

温度和光周期对高原鼠兔和根田鼠最大代谢率的影响

研究了光周期和温度对高原鼠兔（Ochotona curzoniae)和根田鼠（Microtus oeconomus)最大代谢率（MMR）的影响。结果表明在高原鼠兔中,光周期对MMR的影响较小,而低温可显著地导致MMR的增加（P＜0．01）,由此提出温度是高原鼠兔MMR季节性变化的主要生理信号;在根田鼠中,光周期和温度对MMR的影响皆达到显著水平（P＜0．01）,短光照和低温都可导致MMR的增加。     

光照和温度对根田鼠褐色脂肪组织产热能力的影响

测定了根田鼠在室内驯化2周后褐色脂肪组织（BAT）的蛋白含量、线粒体蛋白含量和细胞色素C氧化酶活性的变化。动物进行如下4种处理:23℃,16L:8D;23℃,8L：16D;5℃,16L：8D和5℃,8L:16D.。结果表明,短光照可刺激根田鼠的BAT线粒体细胞色素C氧化酶的活性增加;低温驯化可导致根田鼠的BAT线粒体蛋白含量增加;短光照加低温可进一步促进酶的活性增加。结合个体水平的产热特点,说明根田鼠在产热能力的季节驯化过程中,光周期是一主要的季节调节信号,环境温度进一步增强光照的作用,环境温度和光周期共同作用以诱导其产热能力等方面的生理调节。研究结果支持了环境温度和光周期共同作用以调节动物产热变化的学说。     

Tuning of electronic properties of one-dimensional cyano-bridged Cu-Ni, Cu-Pd, and Cu-Pt bimetallic assemblies by stereochemistry of ligands

Preparations, XPS and electronic spectroscopy, and magnetism of seven new one-dimensional cyano-bridged coordination polymers, chiral [Cu(RR-chxn)₂][Pd(CN)₄] · 2H₂O (1), [Cu(trans-chxn)₂][M(CN)₄] · 2H₂O (2, 4, and 6 for M = Pd, Ni, and Pt), and [Cu(cis-chxn)₂][M(CN)₄] · 2H₂O (3, 5, and 7 for M = Pd, Ni, and Pt) (RR-chxn = cyclohexane-(1R,2R)-diamine, trans-chxn = racemic trans-cyclohexane-(1,2)-diamine, and cis-chxn = racemic cis-cyclohexane-(1,2)-diamine) have been reported in view of tuning of their electronic properties by stereochemistry of chxn ligands and metal-substitution. Comparison of Cu 2p_1/2 and 2p_3/2 peaks of XPS and broad d-d bands around 18 000 cm⁻¹ of electronic spectra are described systematically for 1-7. Variable-temperature magnetic measurement shows that complexes 1-7 indicate weak antiferromagnetic interactions via cyano-bridges. Because of semi-coordination coupled with pseudo Jahn-Teller elongation and electrostatic interaction for 1, the axial Cu-N coordination bond distances of 2.330(7) and 3.092(8) Å are considerably longer than those of equatorial ones in the range from 2.016(6) to 2.030(6) Å. The former bond distances of 1 are intermediate values among the related Ni (2.324(6) and 3.120(8) Å) and Pt (2.34(1) and 3.09(1) Å) complexes.     

Land,livestock, and livelihoods: Changing dynamics of gender,caste, and ethnicity in a Nepalese Village

Over the past 10 years, Ghusel VDC, Lalitpur District has moved from primarily subsistence agriculture into the wider cash economy aided by the Small Farmers' Development Program (SFDP), which provides credit to farmers mainly for the purchase of buffalo for milk production, and by the National Dairy Corporation, which supports local dairy cooperatives. Analysis reveals that buffalo-keeping and milk sales are increasing the well-being of many households, while at the same time creating new inequalities in gender roles and responsibilities, greater inequities between Brahmin and Tamang residents in Ghusel, and placing pressures on the ecosystem for increased supplies of fodder and fuelwood. Evidence suggests that there is critical, need for attention to the social, and particularly gender-based, implications of maintaining livestock for milk sales and to the ecological underpinnings of this livelihood system.     

Structure and function of S-adenosylhomocysteine hydrolase

In mammals, S-adenosylhomocysteine hydrolase (AdoHcyase) is the only known enzyme to catalyze the breakdown of S-adenosylhomocysteine (AdoHcy) to homocysteine and adenosine. AdoHcy is the product of all adenosylmethionine (AdoMet)-dependent biological transmethylations. These reactions have a wide range of products, and are common in all facets of biometabolism. As a product inhibitor, elevated levels of AdoHcy suppress AdoMet-dependent transmethylations. Thus, AdoHcyase is a regulator of biological transmethylation in general. The three-dimensional structure of AdoHcyase complexed with reduced nicotinamide adenine dinucleotide phosphate (NADH) and the inhibitor (1′R, 2′S, 3′R)-9-(2′,3′-dihyroxycyclopenten-1-yl)adenine (DHCeA) was solved by a combination of the crystallographic direct methods program, SnB, to determine the selenium atom substructure and by treating the multiwavelength anomalous diffraction data as a special case of multiple isomorphous replacement. The enzyme architecture resembles that observed for NAD-dependent dehydrogenases, with the catalytic domain and the cofactor binding domain each containing a modified Rossmann fold. The two domains form a deep active site cleft containing the cofactor and bound inhibitor molecule. A comparison of the inhibitor complex of the human enzyme and the structure of the rat enzyme, solved without inhibitor, suggests that a 17° rigid body movement of the catalytic domain occurs upon inhibitor/substrate binding.     

Chiral Separation of G‐type Chemical Warfare Nerve Agents via Analytical Supercritical Fluid Chromatography

Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G‐type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical‐scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(–) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(–) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. Chirality 26:817–824, 2014. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc.     

Influence of Fluoride on Rat Kidney Antioxidant System: Effects of Methionine and Vitamin E

The aim of the study has been to determine and compare the influence upon the kidney antioxidative system, exercised by administration of vitamin E, and vitamin E in combination with methionine, under conditions of oxidative stress induced by sodium fluoride. The experiment was carried out on Wistar FL rats (adult males) that, for 35 days, were administered water, NaF, NaF with vitamin E, or vitamin E with methionine (doses: 10 mg NaF/kg of body mass/24 h, 3 mg vitamin E per 10 μl per rat for 24 h, 2 mg methionine per rat for 24 h). The influence of administered sodium fluoride and antioxidants upon the antioxidative system in kidney was examined by analyzing the concentration of malondialdehyde (MDA) and the activity of the most important antioxidative enzymes (SOD, total and both its isoenzymes, GPX, GST, GR, and CAT). The studies carried out confirmed the disadvantageous effect of the administered dose of NaF upon the antixodiative system in rats (increase in the concentration MDA, decrease activity of all antioxidative enzymes). The administration of vitamin E increased the activity of studied enzymes with the exception of glutathione reductase GR; it also reduced the procesess of lipid peroxidation. It has been found that combined doses of vitamin E and methionine were most effective in inhibiting lipid peroxidation processes. The results confirmed the antioxidative properties of methionine.     

Reorientation of Microfibrils and Microtubules at the Outer Epidermal Wall of Maize Coleoptiles During Auxin-Mediated Growth

Auxin-mediated elongation growth of isolated subapical coleoptile segments of maize (Zea mays L.) is controlled by the extensibility of the outer cell wall of the outer epidermis (Kutschera et al., 1987). Here we investigate the hypothesis that auxin controls the extensibility of this wall by changing the orientation of newly deposited microfibrils through a corresponding change in the orientation of cortical microtubules. On the basis of electron micrographs it is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface. Conversely, reinduction of growth by exogenous auxin is correlated with a relative increase of transversely orientated microfibrils and microtubules at the inner wall surface. These changes can be detected 30–60 min after the removal and addition of auxin, respectively. The functional significance of directional changes of newly desposited wall microfibrils for the control of elongation growth is discussed.     

Gamma-glutamylcysteine protects ergothioneine-deficient Mycobacterium tuberculosis mutants against oxidative and nitrosative stress

Mycobacterium tuberculosis (M.tb.), the causative agent of tuberculosis (TB), cannot synthesize GSH, but synthesizes two major low molecular weight thiols namely mycothiol (MSH) and ergothioneine (ERG). Gamma-glutamylcysteine (GGC), an intermediate in GSH synthesis, has been implicated in the protection of lactic acid bacteria from oxidative stress in the absence of GSH. In mycobacteria, GGC is an intermediate in ERG biosynthesis, and its formation is catalysed by EgtA (GshA). GGC is subsequently used by EgtB in the formation of hercynine-sulphoxide-GGC. In this study, M.tb. mutants harbouring unmarked, in-frame deletions in each of the fives genes involved in ERG biosynthesis (egtA, egtB, egtC, egtD and egtE) or a marked deletion of the mshA gene (required for MSH biosynthesis) were generated. Liquid chromatography tandem mass spectrometry analyses (LC-MS) revealed that the production of GGC was elevated in the MSH-deficient and the ERG-deficient mutants. The ERG-deficient ΔegtB mutant which accumulated GGC was more resistant to oxidative and nitrosative stress than the ERG-deficient, GGC-deficient ΔegtA mutant. This implicates GGC in the detoxification of reactive oxygen and nitrogen species in M.tb.     

In vitro studies of the rabbit immune system. IV. Differential mitogen responses of isolated T and B cells.

The mitogenic responses of separated rabbit lymphocyte populations functionally analogous to mouse T and B cells have been tested in vitro. Purified T cells were prepared by passage over nylon wool (NW) and purified B cells prepared by treatment with antithymocyte serum and complement (ATS + C). ATS + C kills 70% of peripheral blood lymphocytes (PBL's) and 50% of the spleen cells while passage over NW yields 40% of the applied PBL's and 5–23% of the applied spleen cells. NW-purified T cells from the spleen or PBL's respond fully to concanavalin A (Con A) but have a reduced response to phytohemaglutinin (PHA) and little or no response to goat anti-rabbit immunoglobulin (anti-Ig). PBL's that survive ATS + C (B cells) are stimulated by anti-Ig but not by Con A or PHA. B cells purified from spleen do not respond to Con A or PHA but will respond to anti-Ig under appropriate conditions. A full spleen B-cell response to anti-Ig required removal of Ig produced by the cultures that blocked anti-Ig stimulation. It is concluded that, for rabbit lymphocytes, Con A and PHA are primarily T-cell mitogens and that anti-Ig is primarily a B-cell mitogen. However, the mitogen response of unfractionated PBL or spleen cell populations indicates an overlap in reactivity. This could be due to cells sharing T and B properties, alteration of cell populations by the fractionation procedures used, or recruitment of one population in the presence of a mitogenic response of the other population.     

八种脑-肠肽侧脑室内注射对大鼠基础胃酸分泌的影响

用乌拉坦麻醉大鼠作急性实验,采用连续灌流胃并收集流出液的方法,观察向侧脑室内注射微量脑-肠肽对大鼠基础胃酸分泌的影响。实验结果如下:(1)雨蛙肽、八肽胆囊收缩素、促甲状腺素释放激素及四肽胃泌素均使总酸排出量增加;(2)生长抑素、胰多肽、P 物质、胰高血糖素则使总酸排出量减少;(3)上述肽类用侧脑室注射的剂量作肌肉注射,除四肽胃泌素也产生明显的刺激胃酸分泌作用外,对胃酸分泌均无明显影响。以上结果提示,脑内的一些肽类可能以神经递质或调制物的方式,参与中枢对胃酸分泌的调节。     

邻苯二甲酸二丁酯对翡翠贻贝抗氧化酶及脂质过氧化水平的影响

实验室条件下,研究了不同浓度邻苯二甲酸二丁酯(DBP)长期胁迫(15 d)对翡翠贻贝内脏团和外套膜抗氧化酶(超氧化物歧化酶SOD、过氧化氢酶CAT)及脂质过氧化(LPO)水平(以MDA含量表示)的影响,以及受胁迫翡翠贻贝在清洁海水中恢复阶段上述生化指标的变化特征.结果表明:胁迫阶段,0.5和2.5 mg.L-1DBP下翡翠贻贝内脏团SOD活性表现为先抑制后逐渐恢复,12.5和62.5 mg.L-1下则持续受到显著抑制;不同浓度组CAT活性均明显被抑制.LPO水平明显升高.外套膜中,2.5 mg.L-1下SOD活性受到持续诱导,其他浓度组则先被抑制,后随曝露时间延长逐渐被诱导;各浓度组CAT的变化波动较大,没有明显规律;而LPO水平明显升高.净化恢复阶段,12.5和62.5 mg.L-1DBP胁迫下的内脏团SOD和CAT活性恢复较慢,其LPO水平随时间延长逐渐恢复至对照组水平;外套膜中SOD活性呈持续升高趋势,CAT活性和LPO水平则随时间延长恢复到对照组水平.