重金属离子镉对高等植物叶绿体光系统Ⅱ的影响的研究

本文研究了重金属离子Cd++、Pb++、Cu++、Zn++对高等植物（菠菜）离体叶绿体两个光系统光合电子传递功能的影响，以Cd++为代表重点研究了它对光系统II（PSII）的影响，首重讨论了Cd++在PSII的作用部位及作用方式。 Cd++、Pb++、Cu++、Zn++对高等植物叶绿体光合电子传递具有抑制作用，其中对PSII电子传递的抑制作用更为显著。PSII制剂的放氧活性比叶绿体的放氧活性对Cd++的毒害作用更加敏感。不同浓度的Cd++处理后，叶绿体全电子链的电子传递活性比放氧活性的降低速率快。这暗示着PSII氧化侧不是Cd++唯一的作用部位，在PSII电子传递链上还存在一个对Cd~(++)敏感的部位。 Cd++使叶绿体和PSII制剂的DCIP光还原活性降低;可变光受到抑制。加入PSII人工电子供体DPC仅使被抑制的DCIP光还原活性稍有恢复;而加入NH2OH对被抑制的可变荧光无影响。因此我们认为Ca++除了作用于PSII氧化侧外，还直接作用于PSII反应中心。这与Bazzaz和Govindje等提出的Cd++仅作用于PSII氧化侧的观点不同。我们认为可能是Cd++改变了叶绿体或PSII制剂类囊体膜的构型或内环境，使较多的PSII反应中心不易被光活化或使其钝化的缘故。 低温（-196℃）荧光发射光谱表明，Cd++使叶绿体的F686/F736及 F696/F736比值降低。另外，Cd++还可使叶绿体和PSII制剂的低温（-196℃）荧光激发光谱的F480/F436比值下降，使叶绿体表观吸收光谱变平。 温和的SDS-PAGE分析表明，Cd++处理后，叶绿体类囊体膜与PSII制剂类囊体膜中色素蛋白复合物LHC-II的部分寡聚体解聚成单聚体，叶绿体中LHC-II总量减少。进一步用梯度胶分析叶绿体类囊体膜的多肽组成。发现Cd++使属于LHC-II的多肽减少。表明Cd++引起了LHC-II的重新分配或它本身的解离。通过比较Cd++与Mg++对PSII活性的不同影响，我们认为Cd++使激发能不利于向PSII分配，从而破坏了两个光系统的协调合作。这或许是导致PSII电子传递活性显著降低的因素之一。

大蹼铃蟾缓激肽及其制备方法和其基因

本发明涉及大蹼铃蟾缓激肽及其制备方法和其基因，属于生物医学领域。其缓激肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由19个氨基酸组成的一种单链多肽，分子量2180，等电点11.7，多肽氨基酸全序列一级结构为：DLPKINRKGPRPPGFSPFR。制备方法是收集大蹼铃蟾皮肤分泌物，离心去除沉淀、冷冻干燥后，经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码大蹼铃蟾缓激肽基因核苷酸序列由cDNA由829个核苷酸组成，编码成熟大蹼铃蟾缓激肽为第140-196，224-280，308-364，392-448，476-532，560-616位6个核苷酸重复单元片断，从两栖类动物皮肤中得到的缓激肽基因作为基因工程制备缓激肽的应用。

Frog skins keep redox homeostasis by antioxidant peptides with rapid radical scavenging ability

The question of how amphibians can protect themselves from reactive oxygen species when exposed to the sun in an oxygen-rich atmosphere is important and interesting, not only from an evolutionary viewpoint, but also as a primer for researchers interested in mammalian skin biology, in which such peptide systems for antioxidant defense are not well studied. The identification of an antioxidant peptide named antioxidin-RL from frog (Odorrana livida) skin in this report supports the idea that a peptide antioxidant system may be a widespread antioxidant strategy among amphibian skins. Its ability to eliminate most of the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical tested within 2 s, which is much faster than the commercial antioxidant factor butylated hydroxytoluene, suggests that it has a potentially large impact on redox homeostasis in amphibian skins. Cys10 is proven to be responsible for its rapid radical scavenging function and tyrosines take part in the binding of antioxidin-RL to radicals according to our nuclear magnetic resonance assay. (C) 2010 Elsevier Inc. All rights reserved.

Extraction, PCR amplification, and sequencing of mitochondrial DNA from scent mark and feces in the giant panda

To expand the feasibility of applying simple, efficient, non-invasive DNA preparation methods using samples that can be obtained from giant pandas living in the wild, we investigated the use of scent markings and fecal samples. Giant panda-specific oligonucleotide primers were used to amplify a portion of the mitochondrial DNA control region as well as a portion of the mitochondrial DNA cytochrome b gene and tRNA(Thr) gene region. A 196 base pair (bp) fragment in the control region and a 449 bp fragment in the cytochrome b gene and tRNA(Thr) gene were successfully amplified. Sequencing of polymerase chain reaction (PCR) products demonstrated that the two fragments are giant panda sequences. Furthermore, under simulated field conditions we found that DNA can be extracted from fecal samples aged as long as 3 months. Our results suggest that the scent mark and fecal samples are simple, efficient, and easily prepared DNA sources. (C) 1998 Wiley-Liss, Inc.

云南蚜茧蜂科四新种(膜翅目)

报道云南蚜茧蜂科四新种: 莲全脉蚜茧蜂Ephedrus nelumbus、柏蚜茧蜂Aphidius cupressi、滇蚜茧蜂A. dianensis和江川平突蚜茧蜂Lysiphlebia jiangchuanensis。模式标本存中科院昆明动物所。

Mitochondrial genomes of two luminous beetles, Rhagophthalmus lufengensis and R-ohbai (Arthropoda, Insecta, Coleoptera)

We determined the mitochondrial MA (mtDNA) sequences of two luminous beetles (Arthropoda, Insecta, Coleoptera), Rhagophthalmus lufengensis from Yunnan, China and Rhagophthalmus ohbai from Yaeyama Island, Japan. We identified all the 37 mtDNA genes of R. l

Exaggerated Status of

Given its relative ease, screening the entire mitochondrial DNA (mtDNA) for heteroplasmic or novel homoplasmic mutations has become part of the routine diagnostic workup for the molecular geneticist confronted with a disease case exhibiting clinical and b

NATURAL FOODS AND THEIR ECOLOGICAL IMPLICATIONS FOR MACACA-THIBETANA AT MOUNT EMEI, CHINA

Natural food plants of partly provisioned groups of Macaca thibetana included about 196 species belonging to 135 genera and 72 families. The macaques consumed mainly bamboo shoots and fruits for about 2 months in autumn, whereas they relied on active or passive provisions from visitors, a variety of structural parts of plants and a small amount of invertebrates in late spring and summer and ate mainly mature leaves and bark for the rest of the year. About half of the species eaten came from the dense herb and shrub layers. This forest-dwelling species shows a distinctive feeding and foraging pattern in comparison with other macaques, explaining why M. thibetana has the largest body weight of all macaques.

衰老及促智药影响神经细胞膜流动性机制的研究进展

细胞膜流动性通常是指膜脂质的流动性。神经细胞膜功能的正常进行要求膜脂质保持适宜的流动状 态。膜流动性改变将导致膜电位、离子通透性、跨膜物质运输、信号转导等一系列改变。老年动物及阿尔茨海 默氏病(AD) 患者脑神经细胞膜流动性显著降低, 主要与自由基增多引起的脂质过氧化反应、神经细胞钙平衡 失调有关, 此外, 还与其脑内神经元上的受体密度、β- 淀粉样蛋白沉积有关。促智药(吡咯烷酮类、人参皂 甙、银杏叶提取物EGb761) 能明显增强老年动物及AD 患者脑神经细胞膜的流动性。

猕猴输精管内注射高分子聚合物HFMC后对睾丸组织结构的影响

本实验选用具有生育力成年雄性猕猴７只，在直视下行双侧ＨＦＭＣ输精管内注射，每侧剂量分别为３０ｍｇ１只，６０ｍｇ和１００ｍｇ各３只；于注射后２．５年和３．５年分别处死动物，取睾丸组织进行光镜和电镜观察．结果发现：猕猴注射ＨＦＭＣ２．５年后，睾丸光镜大部分曲细精管生精上皮结构完整，排列整齐。仅见局部少数管腔生精上皮层数减少，上皮细胞轻度水样变性等病理改变。电镜下曲细精管内除支持细胞内脂褐素增多，轻度基底膜增厚和精母细胞内质网扩张外，各级生精细胞，支持细胞及细胞间连接复合体等超微结构未见明显异常。注射ＨＦＭＣ３．５年后猕猴的光镜、电镜结果与注射后２．５年结果相似，但局部改变较２．５年组轻。上述结果表明：猕猴输精管内注射一定剂量ＨＦＭＣ节育不会引起睾丸组织的严重病理改变。但是，由于注射ＨＦＭＣ后，ＨＦＭＣ释放Ｈ＋及其对输精管的暂时阻塞，改变了精子生存的内环境，使睾丸出现局部轻度病理改变，随着ＨＦＭＣ逐渐溶解排出，睾丸功能相继恢复正常，配对产仔。为ＨＦＭＣ应用提供了安全性依据。

猕猴、白眉长臂猿、人类染色体普通型脆性部位和G-带的比较研究

近缘动物染色体同源区内的脆性部位在进化上是保守的,可作为染色体具有共同起源的标志, 结合G-带的比较,可用以阐明近缘动物染色体的同源性和染色体进化。图版2图2表1参24

西双版纳热带雨林中榕树动物群落结构与多样性研究

榕树是西双版纳热带雨林生态系统中的一个关键植物类群, 在该类植物中, 形成了以榕树果实、叶片、枝杆、枯枝落叶、土壤为食物、栖息、繁殖环境和帮助榕树授粉、传播种子的动物群落; 榕树和动物之间形成了互相依赖、协同共存、互促发展的紧密关系. 本工作在西双版纳勐仑热带雨林自然保护区、濒危植物迁地保护区、罗梭江边、植物园生活区等固定样地内, 定点、定时对榕树中的动物群落结构和动态、多样性等进行研究, 结果表明: 热带雨林原始林地和榕树种群丰富的环境, 动物群落结构复杂多样, 种类和数量显著增加, 反之则减少。