Pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base moiety as potential antiviral agents

A series of pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base moiety were synthesized, characterised, and evaluated for their activity against tobacco mosaic virus (TMV). Biological assays indicated that several of the derivatives exhibited significant activity against TMV. In particularly, compounds 5y and 5aa displayed excellent inactivating activity against TMV, with half maximal effective concentration (EC₅₀) values of 70.3 and 53.65?μg/mL, respectively, which were much better than that of ribavirin (150.45?μg/mL), and 5aa was superior to ningnanmycin (EC₅₀?=?55.35?μg/mL). Interactions of compounds 5y and 5aa with TMV coat protein (TMV-CP) were investigated using microscale thermophoresis and molecular docking. Compounds 5y and 5aa displayed strong binding capability to TMV-CP with dissociation constant (K_d) values of 22.6 and 9.8?μM, respectively. These findings indicate that pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base may be potential antiviral agents.     

中水技术污水处理工艺去除病毒的效果

中水技术开发既可缓解水资源的紧缺,又能改善城市环境。本文报道用石英粉吸附/洗脱和浓缩棒脱水的二步浓集水病毒技术(回收率为25.4～37.3％),研究中水技术不同处理工艺去除病毒的效果。结果,二级处理可去除掺入病毒的98.9％,结合三级处理的混凝沉淀和过滤,可去除99.976％,再加活性炭吸附或加氯消毒,所得中水分别去除掺入病毒的99.986％和99.991％。经首都机场中水道试验厂水样检测表明,中水中未检测到病毒(<0.23PFU/L)。     

Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells

The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.     

十字花科黑腐病菌中转录调控因子HpaR1调控一个纤维素酶基因的表达

十字花科黑腐病菌（Xcc8004）中的一个转录调控因子XC₂736（HpaR1）在致病过程中具有重要的作用。前期研究发现该转录调控因子可能调控胞外纤维素酶的合成。为了解HpaR1对纤维素酶的转录调控机理,本研究对HpaR1进行原核表达纯化,并与488bp的包含XC₀639的启动子区DNA片段进行凝胶电泳迁移率试验,发现HpaR1与XC₀639启动子可以发生结合。将488bp的XC₀639的启动子DNA片段与报告基因gus融合,构建XC₀639的报告质粒pGUS0639r,分别导入野生型8004菌株和缺失突变体DM2736中,分析发现在突变体背景下GUS的表达水平比野生型背景明显降低。表明HpaR1正调控XC₀639的表达。构建XC₀639的极性整合突变体PK0639,检测发现PK0639几乎丧失胞外纤维素酶的活力;通过功能反式互补构建的互补菌株CPK0639可以恢复纤维素酶活性。研究结果表明HpaR1通过调控纤维素酶基因XC₀639的表达来调控细胞的纤维素酶活性。本研究为更深入地了解HpaR1如何调控细菌生理生化功能奠定了基础。     

Alteration in gene expression profile and biological behavior in human lung cancer cell line NL9980 by nm23-H1 gene silencing

Lung cancer is the leading cause of cancer death in both men and women. Tumor metastasis is an essential aspect of lung cancer progression. nm23-H1 is a metastasis suppressor gene. The molecular mechanism by which nm23-H1 suppresses the metastasis is still unclear. Here, we compared the gene expression profile of human large cell lung cancer cell line NL9980 by nm23-H1 gene silencing with that of negative control cells to comprehensively investigate nm23-H1-mediated changes in gene expression of NL9980 cells. Microarray assay revealed that expression of 733-known genes (1.9%, 733/38,500) were altered in response to nm23-H1 gene silencing, including 466 upregulated genes and 267 downregulated. real-time PCR assay of the expression changes indicated that 81.82% (45/55) of verified genes were consistent with that observed in microarray assay. The upregulated genes included MMP-1, -2, SNAI2, CXCL1, 2, 3, PAI-2, while the downregulated genes included cystatin B, TIMP-2, E-cadherin, centrin-2, all of which have been associated with tumor metastasis. Furthermore, we confirmed by Western blot that the expression of MMP-1 and -2 were significantly increased while that of cystatin B was dramatically decreased in NL9980-nm23-H1 silencing cells. The NL9980-nm23-H1 silencing cells exhibited significantly more S phase growth and invasive ability. Thus, silencing of nm23-H1 gene caused metastasis-related gene expression changes in lung cancer cells. The knockdown of nm23-H1 expression may change the lung cancer cells to a more invasive phenotype through alteration in the expression of a set of genes.     

Nonlocal Immunized Mid-Infrared Magnetic Hot Spots in Graphene Junctions

Magnetic hot spots, which implies confinements and enhancements of magnetic fields, are demonstrated in graphene junctions (GJs) in the mid-infrared range. The appearance of magnetic hot spots in GJs comes from the conduction currents in the junction. In further, the extinction resonance peaks suffer blue shift, along with the increases in the magnetic fields inside junction area, when the junction width reduces. In opposite to the circumstances for electric field enhancements, neither magnetic field enhancements nor resonance frequency of GJs is perturbed by the intrinsic nonlocal electronic response of graphene. Such nonlocality immunized magnetic enhancement could be explained by the polarization dependent property of nonlocal effect.     

蒲公英抗肿瘤活性部位的GC-MS分析研究

目的：考察蒲公英提取物对MCF-7增殖作用的影响,研究蒲公英抗肿瘤活性部位的化学成分。方法：采用MTT法比较蒲公英水提物、醇提物和不同极性提取物对MCF-7增殖的影响;以气相色谱．质谱（GC-MS）联用技术对具有抑制MCF-7人乳腺癌细胞增殖的部位进行分离和鉴定。结果：蒲公英水提物和醇提物对MCF-7细胞均有抑制作用,体外最大抑制率分别达到92．95％、93．59％,蒲公英不同极性溶剂提取物中,氯仿部位抑制MCF-7的增殖,且抑制作用高于醇提和水提物,乙酸乙酯和石油醚部位促进MCF-7的增殖。从蒲公英氯仿提取物中鉴定出80种化合物,占其总量的98．07％。结论：蒲公英氯仿部位具有抗肿瘤活性,为蒲公英抗肿瘤活性成分的研究提供了依据,拓展了筛选中药活性成分的方法。     

The cell cycle related apoptotic susceptibility to arsenic trioxide is associated with the level of reactive oxygen species

Double staining flow cytometry was performed using 7-amino actinomycin D and 6-carboxy-2‘,7‘-dichlorodihydrofluorescein diacetate, to detect the level fluctuation of reactive oxygen species (ROS) during the cell cycle of normal NB4 cells. Our results showed that NB4 cells possessed higher level of ROS in G2/M phase than in G1 and S phases. Double staining flow cytometry, with TdT mediated dUTP nick end labeling (Tunel) and propidium iodide(PI), indicated that As2O3 (2μM) could induce apoptosis in NB4 cells prevailingly from G2/M phase, and this efficacy was enhanced upon co-administration of 2, 3-dimethoxy-1, 4-naphthoquinone (DMNQ) (2.5μM) which could produce the endogenous ROS. These results suggested that different ROS level in different cell cycle phases of NB4 cells might determin the selective induction of G2/M apoptosis and the cells‘ susceptibility to apoptosis by As2O3.     

鄂尔多斯高原西部几种荒漠灌丛群落种间联结关系的研究

采用ＰＣ、ＰＣＣ、ＡＣ、Ｘ２和ｒ等公式对鄂尔多斯高原西部５种典型荒漠灌丛群落种间联结系数的求算,通过这些种间的相互关系,阐述了这些物种对生境要求的差异和分布特点,本文的研究结果对与建立在种群关系基础上的荒漠植被的研究具有重要的意义。