白藜芦醇的药理作用机理和合成途径

白藜芦醇具有多种药理作用,其合成的化学途径与生物途径研究有新的进展。     

The mitochondrial genome of the plant bug Apolygus lucorum （Hemiptera： Miridae）＂ Presently known as the smallest in Heteroptera

The complete mitochondrial （mt） genome of the plant bug, Apolygus lucorum, an important cotton pest, has been sequenced and annotated in this study. The entire circular genome is 14 768 bp in size and represents the smallest in presently known heteropteran mt genomes. The mt genome is encoding for two ribosomal RNA （rRNA） genes, 22 transfer RNA （tRNA） genes, 13 protein coding genes and a control region, and the order, content, codon usage and base organization show similarity to a great extent to the hypothetical ancestral model. All protein coding genes use standard initiation codons ATN. Conventional stop codons TAA and TAG have been assigned to the most protein coding genes; however, COIII, ND4 and ND5 genes show incomplete terminator signal （T）. All tRNA genes possess the typical clover leaf structure, but the dihydrouridine arm of tRNAser（A6N） only forms a simple loop. Secondary structure models of rRNA genes are generally in accordance with the former models, although some differences exist in certain parts. Three intergenic spacers have never been found in sequenced mt genomes of Heteroptera. The phylogenetic study based on protein coding genes is largely congruent with previous phylogenetic work. Both Bayesian inference and maximum likelihood analyses highly support the sister relationship ofA. lucorum and Lygus lineolaris, and Miridae presents a sister position to Anthocoridae.     

Is oral microbiome of children able to maintain resistance and functional stability in response to short-term interference of ingesta?

Dear Editor, A series of studies had focused on the ecological stability of human microbiome (Lozupone et al.,2012;Faith et al.,2013;Moya and Ferrer,2016).Despite the continuous perturbation and the highly personalized composition within the human microbiome (Human Microbiome Project,2012),healthy adults stably maintain their microbial communities in terms of space and time (Faith et al.,2013;Moya and Ferrer,2016;Oh et al.,2016).This stability is proved to be critical for the well-being of human body (Lozupone et al.,2012).On the contrary,major shifts in microbial community composition are often related to diseases (Lynch and Pedersen,2016).     

大穗型水稻生育后期叶片和根系生理的特性

Ｇ Ｅ Ｒ１ 是从玉米 Ｄ Ｎ Ａ 导入水稻的后代变异材料中筛选出的大穗型高产变异系⒚对 Ｇ Ｅ Ｒ１ 生育后期叶片和根系生理特性的研究表明：与受体湘早籼 ８ 号和三系杂交稻汕优 ６３相比, Ｇ Ｅ Ｒ１ 的顶三叶叶绿素含量、蛋白质含量、光合速率、过氧化物酶和超氧化物歧化酶活性降幅小,丙二醛含量增幅小,叶片衰老得到延缓,生育后期根量和根系伤流量较大、发根力和根系 α萘胺氧化力较强⒚生育后期叶片和根系的延缓衰老使得叶片功能期长、光合产物供应充足,是实现大穗多穗条件下水稻高结实率和充实度好的主要内在原因⒚     

虎纹捕鸟蛛毒素-Ⅰ突变体K3A-HWTX-Ⅰ的化学合成与生理活性分析

采用固相Ｆｍｏｃ法在自制自动蛋白质化学工作站上合成了其第３位赖氨酸（Ｋ３）被丙氨酸（Ａ）取代的虎纹捕鸟蛛毒素－Ⅰ的突变体Ｋ３Ａ－ＨＷＴＸ－Ⅰ．合成的突变体用Ｅｄｍａｎ降解和电喷雾质谱进行鉴定．Ｋ３Ａ－ＨＷＴＸ－Ⅰ经谷胱甘肽系统进行氧化复性后通过离子交换和反相ＨＰＬＣ纯化．活性分析结果表明,Ｋ３被Ａ取代后ＨＷＴＸ－Ⅰ的生物活性下降了８０％,提示Ｋ３与ＨＷＴＸ－Ⅰ的生物活性有一定的相关性     

我国古代在食肉目兽类狩猎业方面的伟大成就

食肉目(Carnivora)的兽类大都是珍贵的毛皮兽。皮可以制裘、褥及革;肉可供食用;脂肋可以炼油;有的种类更可提供动物性药材(如虎骨、熊胆等),经济利用价值很高。因此,自古以来食肉目的兽类即为重要的狩猎对象之一。我国古代劳动人民在长期的狩猎实践中,积累了不少有关猎取食肉目兽类的经验。这些宝贵的遗产,如能加以系统整理和总结,对于开展近代的狩猎业来说,不无参考价值。对于我     

Sorption and ecotoxicity of pentachlorophenol polluted sediment amended with rice-straw derived biochar

To investigate the feasibility of using biochar to control organic pollutants in sediments, we extracted biochar from rice-straw combustion residues (RBC) and studied its adsorption ability and effect on seed germination ecotoxicity of pentachlorophenol (PCP). The results showed that the Freundlich and dual-mode models could describe all the sorption isotherm data well, and the log K_OC values increased with increasing RBC content. With 50 mg kg⁻¹ PCP in the sediment, a significant seed growth inhibition (P < 0.01) was observed. The addition of 2.0% RBC lowered the PCP concentration in the extraction liquid from 4.53 to 0.17 mg L⁻¹ and increased the germination rate and root length significantly. Furthermore, it was found that the addition of RBC had no toxic but stimulative effect on root elongation. Consequently, RBC could serve as a potential supersorbent for the remediation of organic pollution in situ.     

Study on the association of p53 codon 72 polymorphisms with risk of gastric cancer in high incidence Hexi area of Gansu Province in China

To investigate the possible association of P53 codon 72 Arg/Pro polymorphisms with risk of gastric cancer in the high incidence Hexi area of Gansu province in China. Blood samples from 140 patients with gastric carcinoma and 125 healthy controls were collected in Hexi area of Gansu province. Polymorphism of P53Arg72Pro was genotyped by PCR-TaqMan. For detection Helicobacter pylori infection, Warhin–Starry staining was used. Three kinds of polymorphisms of P53Arg72Pro were Arg/Arg, Arg/Pro, Pro/Pro. The frequencies in gastric cancer group were 15.7, 60.0, 24.3%, and the frequencies in healthy controls were 25.6, 54.4, 20.0%, respectively. P53 codon 72 Pro carrier genotype (Arg/Pro + Pro/Pro) increased risk of gastric carcinoma with an odds ratio 1.840 (95% CI: 1.006–3.387). Helicobacter pylori infection rate was 68.6% in patients group and 50.4% in healthy controls. Helicobacter pylori infection rate in gastric cancer patients was remarkably higher than that in the controls (OR: 2.147, 95% CI: 1.302–3.541, P = 0.003). Stratification analysis showed that P53 codon 72 Pro carrier genotype with Helicobacter pylori infection was significantly higher in cases than that in the controls (OR: 4.182, 95% CI: 1.850–9.454). P53Arg72Pro polymorphisms could be a risk factor for gastric cancer in high incidence Hexi area of Gansu Province in China. P53 codon 72 Pro carrier genotype and Helicobacter pylori positive infection may have a synergistic effect on gastric cancer in high incidence Hexi area of Gansu Province in China.     

无眼金线鲃及其性状演化

无眼金线鲃Sinocyclocheilus anophthalmus是继我国个旧盲条鳅、无眼平鳅、裸腹盲鲃之后发现的第四种盲鱼。与近似种小孔金线鲃相比,该新种侧线鳞较少。由于它长期生活在黑暗的石灰岩溶洞之中,引起某些性状的适应性变异:眼睛消失;体无色素;鳞片退化,感觉器官特别发达。形态比较结果表明,无眼金线鲃是类似小孔金线鲃的祖先进入地下伏流后,适应黑暗环境而形成的一个种,为本属鱼类进化过程中的一个特化分支。     

云南兔Lepus comus G.Allen的分类订正——包括两个新亚种的描记

云南兔Lepus comus G.Allen是云贵高原和滇西山地目前发现的唯一的一种野兔,初由G.M.Allen（1927）根据采自云南西部腾冲的标本命名。其后,国内外学者（包括G.M.Allen本人在内）对云南兔究竟是一独立种或为高原兔Lepus oiostulus（Hodgson）的一个地理亚种意见纷纭（罗泽珣,1981;高耀亭等,1964;Allen,1938;Ellerman et al.,1951;Angermann,1967;Corbet,1978。我们曾对国内有关单位所收藏的这两个类群的100余号标本进行较详细的对比研究。发现云南兔在形态上与高原兔确有明显区别,在分布上又有同域现象,因而主张仍应将云南兔保持其原定种的种级地位;同时,又查对了采于各地的云南兔所有标本,发现云南北部（丽江）至中部（景东、景谷）标本以及云南东部、南部和贵州西部标本都有异于滇西地模标本,且占有不同的地理分布区。经研究,应属两个新的亚种。其中,云南东部,南部和贵州西部的新亚种,为纪念先师彭鸿绶先生毕生献身于云、贵、川的科学考察事业和他的指导与培养,特以彭先生之姓氏命名,以资纪念。