Design,synthesis and biological evaluation of 1-Aryl-5-(4-arylpiperazine-1-carbonyl)-1H-tetrazols as novel microtubule destabilizers

A series of 1-aryl-5-(4-arylpiperazine-1-carbonyl)-1H-tetrazols as microtubule destabilizers were designed, synthesised and evaluated for anticancer activity. Based on bioisosterism, we introduced the tetrazole moiety containing the hydrogen-bond acceptors as B-ring of XRP44X analogues. The key intermediates ethyl 1-aryl-1H-tetrazole-5-carboxylates 10 can be simply and efficiently prepared via a microwave-assisted continuous operation process. Among the compounds synthesised, compound 6–31 showed noteworthy potency against SGC-7901, A549 and HeLa cell lines. In mechanism studies, compound 6–31 inhibited tubulin polymerisation and disorganised microtubule in SGC-7901 cells by binding to tubulin. Moreover, compound 6–31 arrested SGC-7901cells in G2/M phase. This study provided a new perspective for development of antitumor agents that target tubulin.     

Assessment and Clinical Utility of a Non-Next-Generation Sequencing-Based Non-Invasive Prenatal Testing Technology

Background: Rolling-circle replication (RCR) is a novel technology that has not been applied to cell-free DNA (cfDNA) testing until recently. Given the cost and simplicity advantages of this technology compared to other platforms currently used in cfDNA analysis, an assessment of RCR in clinical laboratories was performed. Here, we present the first validation study from clinical laboratories utilizing RCR technology. Methods: 831 samples from spontaneously pregnant women carrying a singleton fetus, and 25 synthetic samples, were analyzed for the fetal risk of trisomy 21 (T21), trisomy 18 (T18) and trisomy 13 (T13), by three laboratories on three continents. All the screen-positive pregnancies were provided post-test genetic counseling and confirmatory diagnostic invasive testing (e.g., amniocentesis). The screen-negative pregnancies were routinely evaluated at birth for fetal aneuploidies, using newborn examinations, and any suspected aneuploidies would have been offered diagnostic testing or confirmed with karyotyping. Results: The study found rolling-circle replication to be a highly viable technology for the clinical assessment of fetal aneuploidies, with 100% sensitivity for T21 (95% CI: 82.35–100.00%); 100.00% sensitivity for T18 (71.51–100.00%); and 100.00% sensitivity for T13 analyses (66.37–100.00%). The specificities were >99% for each trisomy (99.7% (99.01–99.97%) for T21; 99.5% (98.62–99.85%) for T18; 99.7% (99.03–99.97%) for T13), along with a first-pass no-call rate of 0.93%. Conclusions: The study showed that using a rolling-circle replication-based cfDNA system for the evaluation of the common aneuploidies would provide greater accuracy and clinical utility compared to conventional biochemical screening, and it would provide comparable results to other reported cfDNA methodologies.     

Essential roles of lipoyl domains in the activated function and control of pyruvate dehydrogenase kinases and phosphatase isoform 1.

Four pyruvate dehydrogenase kinase and two pyruvate dehydrogenase phosphatase isoforms function in adjusting the activation state of the pyruvate dehydrogenase complex (PDC) through determining the fraction of active (nonphosphorylated) pyruvate dehydrogenase component. Necessary adaptations of PDC activity with varying metabolic requirements in different tissues and cell types are met by the selective expression and pronounced variation in the inherent functional properties and effector sensitivities of these regulatory enzymes. This review emphasizes how the foremost changes in the kinase and phosphatase activities issue from the dynamic, effector-modified interactions of these regulatory enzymes with the flexibly held outer domains of the core-forming dihydrolipoyl acetyl transferase component.     

Development of bovine oocytes reconstructed with a nucleus from growing stage oocytes after fertilization in vitro

The developmental capacity of reconstructed bovine oocytes that contained nuclei from growing stage oocytes, 70-119 microm in diameter, was assessed after fertilization in vitro. Nuclei from growing stage oocytes of adult ovaries were transferred to enucleated, fully grown germinal vesicle (GV) stage oocytes. After culture in vitro, the reconstructed oocytes matured, forming the first polar body and MII plate. To supply the ability to form pronuclei, the resultant MII plate was transferred to enucleated MII oocytes, which were obtained by in vitro culture of cumulus-oocyte complexes. After fertilization in vitro, 11-15% of the reconstructed oocytes developed to morulae and blastocysts. To assess the ability to develop to term, a total of 27 late morulae and blastocysts were transferred to 19 recipient cows. Of the three cows that subsequently became pregnant, one recipient, who received two embryos derived from reconstructed oocytes with a nucleus from oocytes 100 to 109 microm in diameter, continued the pregnancy to Day 278 of gestation. This pregnancy, however, was unexpectedly a triplet pregnancy that included a set of identical twins and resulted in the premature birth of the calves, followed by death from lack of post-parturient treatment. These results show that bovine oocyte genomes are capable of supporting term development before the oocytes grow to their full size, which suggests that growing stage oocytes can be directly used as a source of maternal genomes.     

Description and ecological traits of a new species of Pitydiplosis (Diptera: Cecidomyiidae) that induces leaf galls on Pueraria (Fabaceae) in East Asia,with a possible diversification scenario of intraspecific groups

A gall midge that induces thick lenticular galls on leaflets of Pueraria species (Fabaceae) in Japan, mainland China, Taiwan and South Korea is described as Pitydiplosis puerariae sp. nov. (Diptera: Cecidomyiidae). Tanaostigmodes puerariae (Hymenoptera: Tanaostigmatidae), described earlier from mainland China as an inducer of the lenticular gall, is regarded to be an inquiline. Pitydiplosis puerariae is distinguishable from the only known congener, the Nearctic Pitydiplosis packardi, by the male genitalia with entire aedeagus and with hypoproct that is as long as cerci and bilobed with a U‐shaped emargination. DNA sequencing data indicate the existence of three genetically different intraspecific groups: (i) “YNT‐montana group” induces galls on Pueraria montana on the Yaeyama Islands, Japan and in northern Taiwan; (ii) “CT‐montana group” on P. montana in central Taiwan; (iii) and “JCK‐lobata group” on Pueraria lobata in mainland China, South Korea and Japan north of Okinoerabu Island. A possible diversification scenario of the three groups is hypothesized based on DNA sequencing data and geohistorical information. A distribution gap of the gall midge on five islands between Tokunoshima and Ishigaki Islands, Japan was confirmed by intensive field surveys. Ecological traits and adult behavior of Pity. puerariae are also described. Its possibility as a potential biological control agent against P. lobata seems counter‐indicated.     

体内表达的休眠蛋白抑制裸鼠肿瘤的生长

休眠蛋白 (restin)是内皮抑素 (endostatin)的同源蛋白 ,它们之间相同的氨基酸占整个蛋白质的 6 2 %。休眠蛋白位于胶原XV羧端的非胶原结构域。在大肠杆菌中重组表达的休眠蛋白经复性后可以专一地抑制牛主动脉内皮细胞的生长 ,并引起凋亡。将鼠源的休眠蛋白基因与信号肽连接后克隆入真核表达载体 pCDNA3,取名为pCDNAXV并转染Bel74 0 4细胞。利用RT PCR和Western印迹证实休眠蛋白在稳定转染株中表达。将这一稳定转染株细胞接入裸鼠皮下观察肿瘤生长 ,发现转染有休眠蛋白基因的肿瘤生长显著慢于对照组 ;由于休眠蛋白基因对肿瘤细胞的增殖没有影响 ,这种抑制作用很可能是通过抑制血管生长来实现的。同时 ,这种方法为研究抑制血管生长蛋白提供了新的手段     

氯氟氰菊酯与阿维菌素增效混配制剂对美洲斑潜蝇的防治效果

低毒化学杀虫剂氯氟氰菊酯与生物源农药阿维菌素混配,通过其对美洲斑潜蝇室内毒力实验,测定共毒系数CTC为161～232,处于明显增效范围内。据此确定最佳配比,配制此增效混剂2%渗透型可湿性粉剂。在北京、山东两地防治美洲斑潜蝇幼虫的田间试验表明药效优良,制剂用量50 g/667m²药后3、7、11天两地区校正防效分别为85.26%～90.76%和86.74%～94.02%,制剂用量25g/667m2两地区相应防效分别为75.28%～85.17%、79.96%～88.68%。该增效混剂防治斑潜蝇速效性和持效性皆佳,成本有所下降,使用可湿粉与乳油相比较,可减少投放入环境的化学品数量,以减少环境污染。     

埃及伊蚊对登革Ⅱ型病毒感染Balb/C实验小鼠的增强

以Balb/C小鼠为实验动物,探讨了埃及伊蚊Aedes aegypti唾液对登革病毒感染宿主的影响。结果显示,在皮下接种剂量相同的情况下,如果Balb/C实验小鼠预先被一定数量的埃及伊蚊叮咬以后,实验小鼠感染病毒的程度有所提高,血清中的抗体滴度明显降低,腹腔巨噬细胞感染登革病毒的阳性率及感染的时间动态曲线也有明显差异,感染高峰期延迟。这些说明实验小鼠被媒介蚊虫叮咬以后变得相对容易被登革病毒感染,可能是媒介蚊虫叮咬小鼠时分泌的唾液对宿主的免疫反应系统有一定作用。因此可以初步肯定埃及伊蚊在登革病毒的感染传播过程中,影响了Balb/C实验小鼠的免疫功能,对登革病毒的感染有一定推动作用。     

树鼩载脂蛋白E的cDNA和蛋白质结构分析

以从树肝脏mRNA逆转录得到的Ⅰ链cDNA为模板 ,运用SMARTRACEPCR技术 ,扩增得到树载脂蛋白E(apoE)cDNA序列 ,并推导出apoE蛋白质的氨基酸序列 .利用分子生物学软件包PCGENE对氨基酸序列和二级结构进行分析和比较 .结果表明 ,树apoEcDNA序列 (作为新基因已被GenBank接收 ,登录号为AF 30 3830 )由 1138bp构成 ,其中 5′非翻译区 6 4bp ,3′非翻译区 135bp ,939bp组成一个完整开放阅读框架 ,与人apoEcDNA的同源性为 86 % .编码 313个氨基酸组成的apoE前体 ,包含 18个氨基酸构成的信号肽和 2 95个氨基酸组成的成熟蛋白 .与人apoE氨基酸序列的同源性为 78% .树apoE与人及其它种属动物apoE在氨基酸组成上相近 ,但比人apoE少4个氨基酸 ,比动脉粥样硬化易感动物家兔apoE多 2个氨基酸 .经Garnier法预测 ,树apoE蛋白二级结构与人apoE相似 ,螺旋构象 (helical) 6 9 9% ,伸展构象 (extended) 16 6 % ,转角构象 (turn)6 0 % ,无规则卷曲 (coil) 7 6 % .     

Simultaneous Saccharification and Ethanol Fermentation of Corn Stover at High Temperature and High Solids Loading by a Thermotolerant Strain Saccharomyces cerevisiae DQ1

The thermotolerant strain Saccharomyces cerevisiae DQ1 was applied to the simultaneous saccharification and fermentation (SSF) at high temperature and high solids loading of the dilute acid-pretreated corn stover in the present study. The SSF using S. cerevisiae DQ1 was operated at 30?% solids loading of the pretreated corn stover with three-step SSF mode and achieved up to ethanol titer of 48?g/L and yield of 65.6?%. S. cerevisiae DQ1 showed strong thermotolerance in both the regular one-step SSF and the three-step SSF with changing temperature in each step. The three-step SSF at 40°C using S. cerevisiae DQ1 tolerated the greater cellulase dosage and solids loading of the pretreated corn stover and resulted in increased ethanol production. The present study provided a practical potential for the future SSF of lignocellulose feedstock at high temperature to reach high ethanol titer.