《猿猴家书》书评

<正>一年前,当我看到《猿猴家书》手稿,立感释然,倍感兴奋。因为从字里行间中,我闻到了中国灵长类学"春"的气息,看到了中国新一代灵长类学者的"范"!这确实是令我心动的一本好书!"我们人类从何而来?往何而去?猿与猴区别为何?猴子会进化成人吗?猴宝宝和人宝宝有何不同?……"书中的每一个科学问题都显得那么绚丽张扬,撩动心中那久违的好奇;而问题的回答又都是那么浅     

茶多糖的抗氧化活性及对细胞氧化损伤的保护机制

茶多糖是一种从茶叶中提取的酸性糖蛋白,具有良好的抗氧化活性。以自由基清除率为指标,分析皖西南地区夏秋茶多糖的抗氧化活性,基于H₂O₂和EDTA-Fe²⁺建立的外源性羟基自由基(·OH)损伤细胞模型和PMA诱导内源性羟基自由基损伤模型,进一步探讨茶多糖对自由基损伤的修复作用机制。结果表明,茶多糖具有良好的体外抗氧化活性,对DPPH·和·OH均具有较强的清除效果,EC₅₀值分别为209.5和535.2μg·mL^–1,最大清除效率与Vc相当。细胞增殖实验表明,外源性和内源性自由基氧化损伤模型中细胞存活率均随着茶多糖浓度的增加而升高,在茶多糖浓度为800μg·mL^–1时细胞存活率分别高达87.41%和85.84%,且显著高于模型组(47.67%和48.03%)。在修复机制上,利用激光共聚焦显微镜显影细胞内活性氧(ROS)分布以及荧光强度,分析结果显示,与模型组相比,茶多糖对于细胞模型中外源和内源性ROS均具有明显的清除效果,与体外抗氧化实验结果一致。茶多糖在体外表...     

海藻多糖的提取和抗Ⅰ型单纯疱疹病毒研究

马尾藻经热水提取,乙醇沉淀,得到褐色粗多糖.经作抗Ⅰ型单纯疱疹病毒检测属高效药物,临床试验治疗单纯疱疹性角膜炎的有效率为84.7％.     

木麻黄NHX基因家族的鉴定及盐胁迫下的表达分析

Na^(+)/H^(+)转运蛋白在植物的耐盐性和生长发育中起关键作用。该研究采用生物信息学方法对木麻黄(Casuarina equisetifolia L.)NHX基因家族成员进行全基因组鉴定和分析,并利用qRT-PCR技术检测NHX基因在盐胁迫下的表达,以探讨木麻黄NHX家族基因的生物学功能,为进一步研究盐胁迫机制以及挖掘其抗逆基因奠定理论基础。结果显示:(1)鉴定获得8个木麻黄NHX基因家族成员(CeqNHX1-8),系统进化树分析发现其可分为Endo、Vac和PM共3个亚家族,分别包含1、5和2个基因;编码氨基酸数为324~546个,分子量为34.87~60.27 kD,等电点在6.29~9.08之间,均为疏水蛋白。(2)基因结构和Motif分析发现,所有CeqNHXs基因的外显子数为2~17不等,且均具有保守的Na^(+)/H^(+)交换结构域;CeqNHX基因的蛋白质二级结构主要以α-螺旋和不规则卷曲为主。(3)木麻黄CeqNHX基因的启动子区含有大量非生物胁迫和激素响应元件,其中CeqNHX5启动子共含有13种共38个元件。(4)qRT-PCR分析表明,CeqNHX基因家族成员在木麻黄根、茎、枝和雄花序中均有不同程度的表达,且多数主要在小枝上表达;在200 mmol/L NaCl处理下,8个木麻黄CeqNHXs基因的表达量均有一定程度的上调。研究表明,木麻黄CeqNHXs基因家族可能参与多种激素和应激反应的调节,且CeqNHXs基因的表达对盐胁迫有显著的响应,推测CeqNHXs基因与木麻黄的耐盐性相关。     

Molecular Phylogenetic Analysis Reveals the New Genus Hemisphaericaspora of the Family Debaryomycetaceae

Four strains of a novel ascomycetous yeast species were recovered from the frass of wood-boring beetles collected from the Baotianman Nature Reserve and the Laojieling Nature Reserve in Henan Province, China. This species produced unconjugated and deliquescent asci with hemispheroid or helmet-shaped ascospores. Analysis of gene sequences for the D1/D2 domain of the large subunit (LSU) rRNA, as well as analysis of concatenated gene sequences for the nearly complete small subunit (SSU) rRNA and D1/D2 domain of the large subunit (LSU) rRNA placed the novel species in a small clade including only one recognised species, Candida insectamans, in the family Debaryomycetaceae (Saccharomycotina, Ascomycota). DNA sequence analyses demonstrated that the novel species was distinct from all currently recognised teleomorphic yeast genus. The name Hemisphaericaspora nanyangensis gen nov., sp. nov. is proposed to accommodate the novel genus and species. The new genus can be distinguished from closely related teleomorphic genera Lodderomyces and Spathaspora through sequence comparison and ascospore morphology. The ex-type strain of H. nanyangensis is CBS 13020^T ( = CICC 33021 = NYNU 13717). Furthermore, based on phenotypic and genotypic characteristics, C. insectamans is transferred to the newly described genus as Hemisphaericaspora insectamans comb. nov., in accordance with the changes in the International Code of Nomenclature for algae, fungi and plants.     

Expression and characterization of a PNPLA3 protein isoform (I148M) associated with nonalcoholic fatty liver disease

A genetic variant of PNPLA3 (patatin-like phospholipase domain-containing 3; PNPLA3-I148M), a serine protease of unknown function, is associated with accumulation of triacylglycerol (TAG) in the liver. To determine the biological substrates of PNPLA3 and the effect of the I148M substitution on enzymatic activity and substrate specificity, we purified and characterized recombinant human PNPLA3 and PNPLA3-I148M. Maximal hydrolytic activity of PNPLA3 was observed against the three major glycerolipids, TAG, diacylglycerol, and monoacylglycerol, with a strong preference for oleic acid as the acyl moiety. Substitution of methionine for isoleucine at position 148 markedly decreased the V(max) of the enzyme for glycerolipids but had only a modest effect on the K(m). Purified PNPLA3 also catalyzed the hydrolysis of oleoyl-CoA, but the V(max) was 100-fold lower for oleoyl-CoA than for triolein. The thioesterase activity required the catalytic serine but was only modestly decreased by the I148M substitution. The enzyme had little or no hydrolytic activity against the other lipid substrates tested, including phospholipids, cholesteryl ester, and retinyl esters. Neither the wild-type nor mutant enzyme catalyzed transfer of oleic acid from oleoyl-CoA to glycerophosphate, lysophosphatidic acid, or diacylglycerol, suggesting that the enzyme does not promote de novo TAG synthesis. Taken together, our results are consistent with the notion that PNPLA3 plays a role in the hydrolysis of glycerolipids and that the I148M substitution causes a loss of function, although we cannot exclude the possibility that the enzyme has additional substrates or activities.     

Single‐Atom to Single‐Atom Grafting of Pt1 onto FeN4 Center: Pt1@FeNC Multifunctional Electrocatalyst with Significantly Enhanced Properties

Nonprecious metal catalysts (NPMCs) Fe?N?C are promising alternatives to noble metal Pt as the oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells. Herein, a new modulation strategy is reported to the active moiety Fe?N₄ via a precise “single‐atom to single‐atom” grafting of a Pt atom onto the Fe center through a bridging oxygen molecule, creating a new active moiety of Pt₁?O₂?Fe₁?N₄. The modulated Fe?N?C exhibits remarkably improved ORR stabilities in acidic media. Moreover, it shows unexpectedly high catalytic activities toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with overpotentials of 310 mV for OER in alkaline solution and 60 mV for HER in acidic media at a current density of 10 mA cm^?2, outperforming the benchmark RuO₂ and comparable with Pt/C(20%), respectively. The enhanced multifunctional electrocatalytic properties are associated with the newly constructed active moiety Pt₁?O₂?Fe₁?N₄, which protects Fe sites from harmful species. Density functional theory calculations reveal the synergy in the new active moiety, which promotes the proton adsorption and reduction kinetics. In addition, the grafted Pt₁?O₂? dangling bonds may boost the OER activity. This study paves a new way to improve and extend NPMCs electrocatalytic properties through a precisely single‐atom to single‐atom grafting strategy.     

Application of Hierarchical Dissociated Neural Network in Closed-Loop Hybrid System Integrating Biological and Mechanical Intelligence

Neural networks are considered the origin of intelligence in organisms. In this paper, a new design of an intelligent system merging biological intelligence with artificial intelligence was created. It was based on a neural controller bidirectionally connected to an actual mobile robot to implement a novel vehicle. Two types of experimental preparations were utilized as the neural controller including ‘random’ and ‘4Q’ (cultured neurons artificially divided into four interconnected parts) neural network. Compared to the random cultures, the ‘4Q’ cultures presented absolutely different activities, and the robot controlled by the ‘4Q’ network presented better capabilities in search tasks. Our results showed that neural cultures could be successfully employed to control an artificial agent; the robot performed better and better with the stimulus because of the short-term plasticity. A new framework is provided to investigate the bidirectional biological-artificial interface and develop new strategies for a future intelligent system using these simplified model systems.     

80例TIA病人的血液流变学分析

目的探讨ＴＩＡ病人的血液流变学改变。方法８０例ＴＩＡ病人均在末次发作后２４ｈ内静脉抽血进行血液流变学测定,并与对照组进行比较。结果ＴＩＡ组病人的红细胞压积、全血高切粘度、全血低切粘度、全血还原高切粘度、全血还原低切粘度、血浆粘度及红细胞聚集性各指标均明显增高,与正常对照组比较有显著性差异。结论血液粘度的增高是引起短暂性脑缺血发作的发病机制之一。