四种白蚁的线粒体DNA限制性片段长度多态性研究(等翅目:鼻白蚁科,木白蚁科)

用６种限制性内切酶分析了４种白蚁的线粒体 Ｄ Ｎ Ａ 限制性片段长度多态性,根据限制性片段差异计算了４种白蚁之间的遗传距离,利用 Ｕ Ｐ Ｇ Ｍ Ａ 聚类分析法构建了分子聚类图。结果表明：尖唇异白蚁与散白蚁属关系很近,聚类分析结果显示应将其归于散白蚊属     

榆梨绵蚜一些型与卵的新发现和记述（同翅目：蚜总科：瘿绵蚜科）

对榆梨绵蚜Ｅｒｉｏｓｏｍａ ｌａｎｕｇｉｎｏｓｕｍ ｄｉｌａｎｕｇｉｎｏｓｕｍ Ｚｈａｎｇ,１９８０的干母,无翅干雌,有翅干雌,无翅侨蚜,有翅性母,雌,雄性蚜放卵进行了描述,除有翅干雌外,其余各型与卵均为首镒记述。所有研究用标本均保存在中国科学院动物研究所昆虫标本馆内。     

牛背梁自然保护区种子植物多样性研究

对牛背梁自然保护区的种子植物多样性进行了研究。据统计,种子植物950种,隶属105科433属,其中,裸子植物4科8属9种,被子植物101科425属941种;木本植物372种,草本植物578种;珍稀濒危保护植物17种,资源植物丰富,分为药用,观赏,食用等10大类型,生态系统多样,按大的类型可划分为森林,灌丛,草甸,裸岩和农田,其中森林面积15055hm^2,占总面积的91.7%。是生态系统的主体。在此基础上,本文还提出了保护植物多样性应采取的对策。     

Afatinib Decreases P‐Glycoprotein Expression to Promote Adriamycin Toxicity of A549T Cells

We investigated the reversal effect of afatinib (AFT) on activity of adriamycin (ADR) in A549T cells and clarified the related molecular mechanisms. A549T cells overexpressing P‐glycoprotein (P‐gp) were resistant to anticancer drug ADR. AFT significantly increased the antitumor activity of ADR in A549T cells. AFT increased the intracellular concentration of ADR by inhibiting the function and expression of P‐gp at mRNA and protein levels in A549T cells. Additionally, the reversal effect of AFT on P‐gp mediated multidrug resistance (MDR) might be related to the inhibition of PI3K/Akt pathway. Cotreatment with AFT and ADR could enhance ADR‐induced apoptosis and autophagy in A549T cells. Meanwhile, the co‐treatment significantly induced cell apoptosis and autophagy accompanied by increased expression of cleaved caspase‐3, PARP, LC3B‐II, and beclin 1. Apoptosis inhibitors had no significant effect on cell activity, while autophagy inhibitors decreased cell viability, suggesting that autophagy may be a self protective mechanism of cell survival in the absence of chemotherapy drugs. Interestingly, when combined with AFT and ADR, inhibition of apoptosis and/or autophagy could enhance cell viability. These results indicated that in addition to inhibit P‐gp, ADR‐induced apoptosis, and autophagy promoted by AFT contributed to the antiproliferation effect of combined AFT and ADR on A549T cells. These findings provide evidence that AFT combined ADR may achieve a better therapeutic effect to lung cancer in clinic. J. Cell. Biochem. 119: 414–423, 2018. © 2017 Wiley Periodicals, Inc.     

Study on the molecular recognition action of lamivudine by human serum albumin

In this work, the interaction of an anti‐HIV drug lamivudine and human serum albumin (HSA) was studied by multispectroscopic and molecular modeling methods. The fluorescence emission spectra showed that the fluorescence of HSA was quenched by lamivudine through static mechanism with HSA‐lamivudine complex produced at ground state. According to the binding equilibriums observed at 4 different temperatures, the number of binding site, binding constant, enthalpy change, entropy change, and Gibbs free energy change of the interaction were calculated. The results indicated that there was only 1 main binding site under present concentration condition, and then, the location of this binding site was ascertained by molecular probe experiments using warfarin and ibuprofen as site markers. The interaction was a spontaneous and exothermic process. Hydrogen bonds and van der Waals force were the major power that fixed lamivudine on Sudlow's site I in subdomain IIA of HSA molecule. The distance between donor and acceptor was determined by Förster's nonradiative fluorescence resonance energy transfer theory. Circular dichroism spectra exhibited the alteration of HSA's secondary structures. Molecular modeling investigation revealed the structure of HSA‐lamivudine complex, including the conformation of lamivudine in binding site, the amino residues close to lamivudine, and the interaction forces between receptor and ligand. The study may be beneficial to therapists in understanding the distribution of lamivudine in vivo and explaining its drug‐resistant mechanism in clinical diagnosis.     

猕猴桃软化过程中阶段性专一酶活性变化的研究

猕猴桃（Ａｃｔｉｎｉｄｉａ ｄｅｌｉｃｉｏｓａ Ｃ．Ｆ．Ｌｉａｎｇ ｅｔＡ．Ｒ．Ｆｅｒｇｕｓｏｎ． ｃｖ． Ｑｉｎｍ ｅｉ）果实采后的软化过程表现为两个明显的阶段,第一阶段软化较快,此时对软化起主要作用的阶段性专一酶是淀粉酶;第二阶段软化速度变慢,此时起主要作用的阶段性专一酶是多聚半乳糖醛酸酶和纤维素酶。乙烯形成酶（ＥＦＥ）的活性高峰出现在两个软化阶段之间,它所引起的乙烯释放对软化有促进作用,因此ＥＦＥ也是与果实软化有关的阶段性专一酶。但是,果胶甲酯酶（ＰＭＥ）的活性变化与果实的软化无相关关系,过氧化物酶（ＰＯＸ）、过氧化氢酶（ＣＡＴ）和ＳＯＤ的活性高峰出现在果实完全软化以后,因此不是果实软化的阶段性专一酶     

荇菜腺毛的发育及其分泌过程的超微结构研究

荇菜 (Nymphoides peltatum (Gmel.) O.Kuntz)腺毛由具分泌功能的单列圆筒状细胞组成。它们起源于苗端倒数第二叶原基近轴面 ,由原表皮细胞发育而来。处于分泌期的腺毛细胞其胞质浓厚 ,液泡化程度小。细胞内具丰富的线粒体、高尔基体和内质网等细胞器 ,还具发达的胞间连丝。粘液物质由高尔基体分泌小泡、内质网分泌小泡及多膜体共同携带至细胞边缘 ,经胞吐和渗透相结合的方式分泌至细胞外。腺毛细胞侧壁因积有大量分泌物而呈膨胀状态。经检测 ,粘液由多糖和蛋白质组成 ,对营养芽的生长发育起保护作用。     

新疆喀什凹陷原油中的孢子花粉

记述了新疆塔里木盆地喀什凹陷原油中萃取出的孢子花粉化石 30属 46种 .基于原油中孢粉化石的研究 ,追朔了该含油区的油源 ,并探讨了石油运移机理 .根据原油孢粉集合的特征 ,下侏罗统康苏组和中侏罗统杨叶组及塔尔尕组应是本区的油源岩系 .原油中来自油源岩系孢粉化石的发现 ,说明微裂隙是石油初次运移的通道 ,裂隙、节理、断层、不整合面等是石油二次运移的通道     

Optimal secretion of alkali-tolerant xylanase in <Emphasis Type="Italic">Bacillus subtilis</Emphasis> by signal peptide screening

Xylanases are industrially important enzymes for xylan digestion. We experimentally screened over 114 Sec and 24 Tat pathway signal peptides, with two different promoters, for optimal production of an alkaline active xylanase (XynBYG) from Bacillus pumilus BYG in a Bacillus subtilis host. Though both promoters yielded highly consistent secretion levels (0.97 Pearson correlation coefficient), the Sec pathway was found to be more efficient than the Tat pathway for XynBYG secretion. Furthermore, the optimal signal peptide (phoB) for XynBYG secretion was found to be different from the optimal peptides for cutinase and esterase reported in previous studies. A partial least squares regression analysis further identified several statistically important variables: helical properties, amino acid composition bias, and the discrimination score in Signal P. These variables explain the observed 23 % variance in the secretion yield of XynBYG by the different signal peptides. The results also suggest that the helical propensity of a signal peptide plays a significant role in the beta-rich xylanase, but not in the helix-rich cutinase, suggesting a coupling of the conformations between the signal peptide and its cargo protein for optimal secretion.