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Nature Contents 27 April 2006 (Vol. 440 pp.1089-1244)
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[自然要览] （选自英国Nature杂志，2006年4月27日出版） 封面故事：CRP蛋白与心脏病的治疗 Targeting C-reactive protein for the treatment of cardiovascular disease C-活性蛋白（CRP）是炎症和感染等症状的一个临床标记，但它也与受损的细胞结合， 激发其补体（即参与免疫反应的血清蛋白复合物）。由补体调控的炎症反应加重心脏病 中的组织损伤，人类CRP在一个急性心肌梗塞的大鼠模型中通过一个依赖于补体的机制 加重损伤程度。这些发现表明，CRP是以保护心脏为目的的药物的一个可能的作用目 标。Pepys等人因此便设计了一种专门抑制CRP的小分子抑制剂。这种“回文结构”的化 合物的5个分子被面对面排列的两个五聚CRP分子所结合，如本期封面图片上该复合物的 X-射线晶体结构所示。该抑制剂完全阻断人类CRP 在正经历急性心肌梗塞的大鼠身上的 不良作用，说明早期通过治疗手段抑制CRP，也许对心脏病患者有好处。（Letter p. 1217）（封面图片：S. Wood, M. Jenvey, S. Kolstoe & D. Thompson） 整合酶的晶体结构(Antibiotic resistance vectors) Structural basis for broad DNA-specificity in integron recombination 整合蛋白（Integrons）是移动的DNA元素，在通过从环境中捕捉基因来在致病细菌中传 播抗生素抗性中扮演一个重要角色。整合酶有一个独特的本领，即它能识别和重组关系 很远的DNA序列。它的这种本领有助于提高整合蛋白将“基因盒”从一个细菌转移到另 一个细菌的能力。现在，研究人员已经确定了与一个目标DNA结合在一起的一个整合酶 的晶体结构，该结构显示了整合酶的亚单元何以能够通过一个涉及两个翻转到双螺旋外 的碱基的机制来适应两个不同的DNA序列。（Article p. 1157; News and Views） 关于太阳系巨型行星轨道倾角的新观点 (Battle of the giants) Origin of the obliquities of the giant planets in mutual interactions in the early Solar System 太阳系的巨型行星在相当奇特的轨道上运行，因为它们的轨道都有很大的倾斜度，即它 们的旋转轴相对于轨道平面都有一个很大的倾角。它们的倾斜度的形成，曾被认为是由 于几十亿年前在太阳系外层与地球大小的小行星发生了擦边碰撞。但这种假设不能解释 所有观测结果。Adrián Brunini提出了另一个模型，按照该模型，这些巨型行星是在 它们的形成过程中通过引力相互作用获得很大倾斜度的。这个新的模拟结果为关于太阳 系动态的一个模型提供了支持，后者认为，这些巨型行星在经过长期稳定之后迅速迁移 到了新位置。（Letter p. 1163） 关于铜氧化物超导性的新模型（On charge） Electron–phonon coupling reflecting dynamic charge inhomogeneity in copper oxide superconductors 科学家对简单金属中超导性的性质已经非常了解了，但标准理论不能解释高温铜氧化物 超导体的关键性质。现在，无弹性中子散射测量实验，显示了铜氧化物超导体中某些晶 格振荡的非传统行为，这种行为导致广泛的电子-光子偶合。该结果支持这样一个模 型，这个模型认为，电荷载体汇聚起来，形成由电荷构成的“河流”，超导性就源自这 种“河流”。（Letter p. 1170; News and Views） 关于“应变硬化”机理的新理论（Strength in numbers） Dislocation multi-junctions and strain hardening “应变硬化”（也称为“加工硬化”）是工程师们所非常看重的晶体材料的一个性质， 它指的是，在施加负荷的情况下，高强度材料会变得更强。多年来，“应变硬化”被认 为来自成对位移碰撞，在这种碰撞过程中，相互交叉的位移形成产生强度的接合点。现 在，来自劳伦斯*利弗莫尔国家实验室的一个小组发现，该理论是不全面的，因为它忽 略了“多体位移相互作用”。以用钼晶体所做实验为依据的新的模拟结果表明，晶体在 应力作用下发生硬化，是因为位移线三个一组捆绑在一起，变成很紧的结，这些结形成 多个接合点。（Letter p. 1174） 雨量变化的重建模型（A long rain） The twentieth century was the wettest period in northern Pakistan over the past millennium 气候变暖可能会明显改变全球雨量及其分布，而且还可以说，降雨的改变对人类生计及 生态系统的直接影响要大于气温的改变。研究人员利用由树木年轮获得的一个以年为分 辨率的氧同位素记录，来生成巴基斯坦北部山区降雨量变化的一个千年尺度的重建模 型。所获得的数据显示，在19世纪后期和20世纪，降雨量有明显增加，使这一时期成为 过去千年间最湿润的时期。与其他气候重建模型所做的比较表明，水文周期有大尺度的 强化，这与工业化和全球变暖的开始在时间上是一致的。这种变化前所未有的幅度足以 说明，人类活动对变化的出现是有贡献的。（Letter p. 1179; News and Views） 所有脊椎动物最后一个共同祖先有鳃囊（Jaw, jaw not gill, gill） Lamprey-like gills in a gnathostome-related Devonian jawless vertebrate 鳃囊见于现存的“圆口纲脊椎动物” (八目鳗类鱼和七鳃鳗)和它们的化石祖先。人们 早就怀疑所有无颌脊椎动物都有这种鳃囊，但一直缺乏确凿的证据来支持这种观点。现 在，研究人员在一个保存完好的、距今3.7亿年前的Endeiolepis化石中发现了七鳃鳗一 样的鳃。这种动物被称为“裸露的无甲类”，因为其身上没有鳞片，所以可能是滑溜 的。无甲类是处在演化树根部的有颌类，即与有颌脊椎动物的关系比与圆口纲脊椎动物 的关系更近的无颌脊椎动物，所以该发现说明，鳃囊过去曾存在于所有脊椎动物的最后 一个共同祖先身上，后来在有颌脊椎动物身上消失了。（Letter p. 1183） 珊瑚本身在其恢复能力中所起的作用（Coral recovery） Heterotrophic plasticity and resilience in bleached corals 海水温度升高引起大范围珊瑚变白和死亡，并且还有可能对这些重要的生态系统造成永 久性损害。珊瑚变白是当通常为珊瑚提供食物的共生微藻从其寄生的珊瑚上被释放出来 时出现的。当这种微藻被释放出来后，珊瑚就会失去色素，看起来几乎是白的。一些珊 瑚能经受住变白过程，但我们对在变白过程中能确保珊瑚存活下来的机制却了解很少。 迄今为止，研究工作主要集中在微藻上，而珊瑚主体的生理特征在变白和恢复中的作用 却在很大程度上被忽略了。现在，对夏威夷卡内奥赫湾已经变白、正在恢复的珊瑚所做 的一项研究表明，珊瑚主体在其恢复过程及恢复能力中可以起重要作用。增加珊瑚所吃 的浮游动物的供应，可提供另外一个食物来源，大大增强珊瑚在变白事件中的存活能 力。（Letter p. 1186） 出生前接触性激素的影响（Maternal influence） Rank-related maternal effects of androgens on behaviour in wild spotted hyaenas 哺乳动物如果在出生前接触父母的性激素，会对它们的成长和发育产生深远影响。 在 以雌性为主导的斑点鬣狗的社会中，这一现象被发展到了极致。Dloniak等人首次揭示 了一个鬣狗的社会地位与其在怀孕期间接触雄性激素情况之间的关系。这种关系还与其 后代习惯性的攻击性密切相关，说明存在一个通过出生前接触性激素来将与地位有关的 特征从母亲传递给后代的机制。（Letter p. 1190） 是否存在人类所特有的语言处理能力?（Not a word） Recursive syntactic pattern learning by songbirds Noam Chomsky关于“衍生语法”的研究工作，导致了这样一个概念的形成：一组规则能 产生一种自然的语言，该语言具有一个分成不同层次的语法；也导致了这样一个观点的 形成：这种形成语言的能力是人类所特有的能力。在用欧洲八哥所做的一系列实验中， 研究人员用几种类型的“鸣啭”和“卡塔”声代替人类语言中的单词，这些鸟儿用一种 符合同一标准的方式学习划分句子的语法结构。它们的表现按照这一标准可以说几乎跟 人类是一样的。所以，如果说存在人类所独有的语言处理能力，那么它们可能更多的是 与背景无关的，或在Noam Chomsky所说的语法等级中处于更高的层次。或者，根本不存 在能将人类语言与非人类交流系统区分开来的单一特性或处理能力。（Letter p.1204; News and Views p. 1204） 缺氧肿瘤细胞中LOX酶含量较高（Hypoxia in tumours） Lysyl oxidase is essential for hypoxia-induced metastasis 肿瘤含有低氧（缺氧）区域，因为癌细胞的生长和分裂速度快于血管提供氧气的速度。 这些区域的细胞非常容易转移，虽然该现象的原因尚不知道。现在，Erler等人在缺氧 细胞中发现了高浓度的酶“lysyl氧化酶”（LOX）。肿瘤中高LOX含量与乳腺癌患者预 后差有关。在小鼠身上，抑制LOX可减少转移，说明它是一个候选治疗目标。（Letter p. 1222） |
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---------------------- NEWS AND VIEWS ---------------------- Language: Startling starlings Recursion, once thought to be the unique province of human language, now seems to be within the ken of a common songbird -- perhaps providing insight into the origins of language. Gary F. Marcus http://www.nature.com/nature/jou ... /full/4401117a.html Superconductivity: Quantum stripe search Do quantum stripes exist or not? Further indirect evidence for this controversial behaviour of electrons in high-temperature superconductors comes from measurements of atomic-lattice vibrations. Jan Zaanen http://www.nature.com/nature/jou ... /full/4401118a.html Biomaterials: Gripping stuff Rosamund Daw http://www.nature.com/nature/jou ... /full/4401119a.html Palaeoclimatology: The woods fill up with snow Palaeoclimatological evidence covering the past millennium suggests that the global water cycle has changed in the past century. Agreement with climate models points to human activity as the main cause. Michael N. Evans http://www.nature.com/nature/jou ... /full/4401120a.html Molecular biology: Singled out for integration Bacteria regularly swap genes among themselves. The structure of an enzyme that mediates the spread of certain DNA elements reveals the unusual way in which they take up residence in new genomes. Michael Chandler http://www.nature.com/nature/jou ... /full/4401121a.html ---------------------- BRIEF COMMUNICATIONS ---------------------- Gene therapy: Therapeutic gene causing lymphoma Insight into risks posed by corrective gene therapy comes from an immunodeficient mouse model. Niels-Bjarne Woods, Virginie Bottero, Manfred Schmidt, Christof von Kalle and Inder M. Verma Abstract: http://www.nature.com/nature/journal/v440/n7088/abs/4401123a.html Article: http://www.nature.com/nature/jou ... /full/4401123a.html BRIEF COMMUNICATIONS ARISING Molecular virology: Was the 1918 pandemic caused by a bird flu? Mark J. Gibbs and Adrian J. Gibbs Abstract: http://www.nature.com/nature/jou ... bs/nature04823.html Article: http://www.nature.com/nature/jou ... ll/nature04823.html Molecular virology: Was the 1918 flu avian in origin? Janis Antonovics, Michael E. Hood and Christi Howell Baker Abstract: http://www.nature.com/nature/jou ... bs/nature04824.html Article: http://www.nature.com/nature/jou ... ll/nature04824.html Molecular virology: Was the 1918 pandemic caused by a bird flu? Was the 1918 flu avian in origin? (Reply) Jeffery K. Taubenberger, Ann H. Reid, Raina M. Lourens, Ruixue Wang, Guozhong Jin and Thomas G. Fanning Abstract: http://www.nature.com/nature/jou ... bs/nature04825.html Article: http://www.nature.com/nature/jou ... ll/nature04825.html ---------------------- INSIGHT ---------------------- INTRODUCTION Early Universe Leslie Sage http://www.nature.com/nature/jou ... /full/4401125a.html REVIEW ARTICLE Cosmology from start to finish Charles L. Bennett Abstract: http://www.nature.com/nature/jou ... bs/nature04803.html Article: http://www.nature.com/nature/jou ... ll/nature04803.html Is our Universe natural? Sean M. Carroll Abstract: http://www.nature.com/nature/jou ... bs/nature04804.html Article: http://www.nature.com/nature/jou ... ll/nature04804.html The large-scale structure of the Universe Volker Springel, Carlos S. Frenk and Simon D. M. White Abstract: http://www.nature.com/nature/jou ... bs/nature04805.html Article: http://www.nature.com/nature/jou ... ll/nature04805.html High-redshift galaxy populations Esther M. Hu and Lennox L. Cowie Abstract: http://www.nature.com/nature/jou ... bs/nature04806.html Article: http://www.nature.com/nature/jou ... ll/nature04806.html Heavy element synthesis in the oldest stars and the early Universe John J. Cowan and Christopher Sneden Abstract: http://www.nature.com/nature/jou ... bs/nature04807.html Article: http://www.nature.com/nature/jou ... ll/nature04807.html ---------------------- ARTICLE ---------------------- Structural basis for broad DNA-specificity in integron recombination Crystallization of an integrase complex with target site DNA reveals that two flipped-out bases position the integrase subunits correctly, thus allowing different DNA sequences to be accommodated. Douglas MacDonald, Gaelle Demarre, Marie Bouvier, Didier Mazel and Deshmukh N. Gopaul Abstract: http://www.nature.com/nature/jou ... bs/nature04643.html Article: http://www.nature.com/nature/jou ... ll/nature04643.html ---------------------- LETTERS ---------------------- Origin of the obliquities of the giant planets in mutual interactions in the early Solar System The present obliquities of the giant planets were probably achieved when Jupiter and Saturn crossed the 1:2 orbital resonance during a specific migration process. Adri??n Brunini Abstract: http://www.nature.com/nature/jou ... bs/nature04577.html Article: http://www.nature.com/nature/jou ... ll/nature04577.html Wave and defect dynamics in nonlinear photonic quasicrystals A photonic equivalent of a quasicrystal is created in which wave and defect dynamics can be made visible -- for example, it is shown that a dislocation introduced in the photonic quasicrystal is healed by re-arrangements of the lattice. Barak Freedman, Guy Bartal, Mordechai Segev, Ron Lifshitz, Demetrios N. Christodoulides and Jason W. Fleischer Abstract: http://www.nature.com/nature/jou ... bs/nature04722.html Article: http://www.nature.com/nature/jou ... ll/nature04722.html Electron-phonon coupling reflecting dynamic charge inhomogeneity in copper oxide superconductors Inelastic scattering measurements reveal a strong electron-lattice coupling in copper oxide superconductors -- which goes against conventional theory and suggests that that electron- lattice coupling is associated with charge inhomogeneity. D. Reznik, L. Pintschovius, M. Ito, S. Iikubo, M. Sato, H. Goka, M. Fujita, K. Yamada, G. D. Gu and J. M. Tranquada Abstract: http://www.nature.com/nature/jou ... bs/nature04704.html Article: http://www.nature.com/nature/jou ... ll/nature04704.html Dislocation multi-junctions and strain hardening Vasily V. Bulatov, Luke L. Hsiung, Meijie Tang, Athanasios Arsenlis, Maria C. Bartelt, Wei Cai, Jeff N. Florando, Masato Hiratani, Moon Rhee, Gregg Hommes, Tim G. Pierce and Tomas Diaz de la Rubia Abstract: http://www.nature.com/nature/jou ... bs/nature04658.html Article: http://www.nature.com/nature/jou ... ll/nature04658.html The twentieth century was the wettest period in northern Pakistan over the past millennium Long-term precipitation reconstructions indicate a large-scale intensification of the hydrological cycle coincident with the onset of industrialization and global warming -- such unprecedented amplitude argues for a human role. Kerstin S. Treydte, Gerhard H. Schleser, Gerhard Helle, David C. Frank, Matthias Winiger, Gerald H. Haug and Jan Esper Abstract: http://www.nature.com/nature/jou ... bs/nature04743.html Article: http://www.nature.com/nature/jou ... ll/nature04743.html Lamprey-like gills in a gnathostome-related Devonian jawless vertebrate Philippe Janvier, Sylvain Desbiens, Jason A. Willett and Marius Arsenault Abstract: http://www.nature.com/nature/jou ... bs/nature04471.html Article: http://www.nature.com/nature/jou ... ll/nature04471.html Heterotrophic plasticity and resilience in bleached corals Andr?(c)a G. Grottoli, Lisa J. Rodrigues and James E. Palardy Abstract: http://www.nature.com/nature/jou ... bs/nature04565.html Article: http://www.nature.com/nature/jou ... ll/nature04565.html Rank-related maternal effects of androgens on behaviour in wild spotted hyaenas A relationship between exposure to androgens during pregnancy and social rank is also strongly related to the habitual aggressiveness of hyaena offspring -- suggesting a mechanism for the transfer of status-related traits from mother to offspring through prenatal hormone exposure. S. M. Dloniak, J. A. French and K. E. Holekamp Abstract: http://www.nature.com/nature/jou ... bs/nature04540.html Article: http://www.nature.com/nature/jou ... ll/nature04540.html The DNA sequence, annotation and analysis of human chromosome 3 Donna M. Muzny et al. Abstract: http://www.nature.com/nature/jou ... bs/nature04728.html Article: http://www.nature.com/nature/jou ... ll/nature04728.html Pluripotency of spermatogonial stem cells from adult mouse testis Stem cells isolated from the testis of adult mice show similar characteristics to embryonic stem cells -- suggesting that stem cells capable of forming many different tissues may be accessible from testicular biopsies. Kaomei Guan, Karim Nayernia, Lars S. Maier, Stefan Wagner, Ralf Dressel, Jae Ho Lee, Jessica Nolte, Frieder Wolf, Manyu Li, Wolfgang Engel and Gerd Hasenfuss Abstract: http://www.nature.com/nature/jou ... bs/nature04697.html Article: http://www.nature.com/nature/jou ... ll/nature04697.html Recursive syntactic pattern learning by songbirds Timothy Q. Gentner, Kimberly M. Fenn, Daniel Margoliash and Howard C. Nusbaum Abstract: http://www.nature.com/nature/jou ... bs/nature04675.html Article: http://www.nature.com/nature/jou ... ll/nature04675.html TMP21 is a presenilin complex component that modulates γ-secretase but not ε-secretase activity Fusheng Chen, Hiroshi Hasegawa, Gerold Schmitt-Ulms, Toshitaka Kawarai, Christopher Bohm, Taiichi Katayama, Yongjun Gu, Nobuo Sanjo, Michael Glista, Ekaterina Rogaeva, Yosuke Wakutani, Raphaelle Pardossi-Piquard, Xueying Ruan, Anurag Tandon, Frederic Checler, Philippe Marambaud, Kirk Hansen, David Westaway, Peter St George-Hyslop and Paul Fraser Abstract: http://www.nature.com/nature/jou ... bs/nature04667.html Article: http://www.nature.com/nature/jou ... ll/nature04667.html A voltage-gated proton-selective channel lacking the pore domain I. Scott Ramsey, Magdalene M. Moran, Jayhong A. Chong and David E. Clapham Abstract: http://www.nature.com/nature/jou ... bs/nature04700.html Article: http://www.nature.com/nature/jou ... ll/nature04700.html Targeting C-reactive protein for the treatment of cardiovascular disease A new drug inhibits the adverse effects of C-reactive protein, a blood protein that has been shown to exacerbate damage in the heart and brain after blockage of the blood supply. Mark B. Pepys, Gideon M. Hirschfield, Glenys A. Tennent, J. Ruth Gallimore, Melvyn C. Kahan, Vittorio Bellotti, Philip N. Hawkins, Rebecca M. Myers, Martin D. Smith, Alessandra Polara, Alexander J. A. Cobb, Steven V. Ley, J. Andrew Aquilina, Carol V. Robinson, Isam Sharif, Gillian A. Gray, Caroline A. Sabin, Michelle C. Jenvey, Simon E. Kolstoe, Darren Thompson and Stephen P. Wood Abstract: http://www.nature.com/nature/jou ... bs/nature04672.html Article: http://www.nature.com/nature/jou ... ll/nature04672.html Lysyl oxidase is essential for hypoxia-induced metastasis Janine T. Erler, Kevin L. Bennewith, Monica Nicolau, Nadja Dornhofer, Christina Kong, Quynh-Thu Le, Jen-Tsan Ashley Chi, Stefanie S. Jeffrey and Amato J. Giaccia Abstract: http://www.nature.com/nature/jou ... bs/nature04695.html Article: http://www.nature.com/nature/jou ... ll/nature04695.html Detecting transient intermediates in macromolecular binding by paramagnetic NMR Nuclear magnetic resonance spectroscopy was used to detect transient intermediates that occurred when the HOXD9 homeodomain was searching for its target sequence in a short DNA duplex, and determined that this transcription factor binds to non-cognate DNA sites to enhance the rate of specific association. Junji Iwahara and G. Marius Clore Abstract: http://www.nature.com/nature/jou ... bs/nature04673.html Article: http://www.nature.com/nature/jou ... ll/nature04673.html |
2楼2006-05-01 15:24:54
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