Interferon enhances 2-5A synthetase in embryonal carcinoma cells

Mouse teratocarcinomas provide a useful model of mammalian differentiation, because the malignant embryonal carcinoma (EC) stem cells of such tumours may produce various differential cell types in vivo or in vitro. Many EC cell lines have now been established and classified on the basis of their ability to differentiate in vivo into cell types characteristically derived from any of the three germ layers. There is convincing evidence that EC cells can neither produce interferon, nor respond to it by becoming resistant to virus, whereas differentiated cells derived from EC lines behave normally in both respects. We investigated the lack of responsiveness of EC cells towards interferon by measuring the levels of two double-stranded RNA-dependent enzyme activities recently shown to be enhanced by interferon. We report here that on treatment with interferon, EC cells show increased 2-5A synthetase levels comparable to those found in differentiated cells, while there is little or no effect on kinase activity in EC cells, in contrast to their differentiated counterparts.     

Natural occurrence of 2-5A in interferon-treated EMC virus-infected L cells.

Until now the interferon-mediated 2'-5' adenine oligonucleotide inhibitors (2-5A) of cell-free protein synthesis have not been detected in intact cells. Here we report their natural occurrence in interferon-treated, EMC virus-infected mouse L cells in amounts consistent with the idea that they play a part in the inhibition of virus growth.     

5-(2-硫甲基-4-甲基)-嘧啶基-戊二炔-1-醇山梨酸酯的合成、表征及其环化

合成了5-(2-硫甲基-4-甲基)-嘧啶基-戊二炔-1-醇山梨酸酯,并用IR、UV-vis、1H、13C、DEPT、gCOSY、gHSQC和gHMBC等对产物进行了表征.此化合物具有两个共轭系统,在gHMBC中检测到了五阶和六阶碳氢相关信号.在光热条件下,此化合物发生分子内环加成形成苯环结构.     

3-[5-(α-萘)-2H-四唑-2-亚甲基]-4-芳酰基-1,2,4-三唑-5-巯基乙酸类化合物的合成

以3-[5-(α-萘)-2H-四唑-2-亚甲基]-4-芳酰基-1.2.4-三唑啉-5-硫酮为原料合成了10个新的3-[5-(α-萘)-2H-四唑2-亚甲基]-4-芳酰基-1,2.4-三唑-5-巯基乙酸类化合物,所有化合物经元素分析,部分化合物经IR,~1H-NMR以及MS裂解碎片分析确定了其结构.观察了这类化合物对小麦胚芽生长的调节作用.     

新法合成1,1-二氯-2-甲氧基-2-(5-羧甲氧呋喃-2)乙烯

提出了一种有效的、新的合成1.1-二氯-2-甲氧基-2-(5-羧甲氧呋喃-2)乙烯的方法.     

2-甲基-3-氨基-5-硝基吡啶的合成研究

硝基吡啶类化合物广泛用于有机合成,特别是杂环药物及细胞因子抑制剂的合成。本文以粘溴酸为原料,分别经与亚硝酸钠反应、与3-氨基巴豆酸乙酯环合、水解、与DPPA反应、脱保护等五步反应最终得到目标产物2-甲基-3-氨基-5-硝基吡啶。此方法仅需要最后一步进行柱纯化,操作简单,后处理方便,总收率为9.1%。     

2-对甲苯氧甲基-5-芳基-1,3,4-噁二唑化合物的合成与结构表征

对甲基苯氧乙酸乙酯与水合肼反应制得对甲基苯氧乙酰肼,该化合物在以碳酸钠作缚酸剂,分别与苯甲酰氯、4-氯苯甲酰氯、4-甲基苯甲酰氯、4-甲氧基苯甲酰氯、3,4,5-三甲氧基苯甲酰氯、3,5-二甲基苯甲酰氯和4-硝基苯甲酰氯反应得到相应的N,N’-二酰基肼3a一3g,然后在PC吗作用下,脱水环化成2-对甲苯氧甲基-5-芳基-1,3,4-噁二唑化合物4a-4g．通过元素分析,IR,’HNMS对其结构进行表征,并对其裂解途径进行了探讨。     

5-正丙基-2-(3,5-二氟苯基)嘧啶的合成

对新型的液晶材料5-正丙基-2-(3,5-二氟苯基)嘧啶的合成路线进行了改进.从3,5-二氟苯甲腈出发,通过加成、取代、环合等反应得到5-正丙基-2-(3,5-氟苯基)嘧啶,总收率为51.6%.其中通过正戊醛,利用Vilsmeier 试剂,以81.8%的收率实现了中间体2-正丙基-3-二甲氨基丙稀醛的合成.     

微波辐射条件下合成2-芳基-5-[5＇-（4＇＇-氯代苯基）-2’-呋喃基]-1，3，4-噁二唑

在微波辐射条件下，5-(4’-氯苯基)-2-呋喃甲酸与取代的芳甲酰肼通过环合剂POCl3作用可一步得到2-芳基-5-[5’-(4k氯代苯基)-2’-呋喃基]-1，3，4-噁二唑．该法与传统方法相比较具有反应速度快、产率高和后处理简单等优点．     

MNP-端粒酶反义寡核苷酸复合物诱导HL-60细胞凋亡

反义寡核苷酸具有抑制细胞基因表达作用,对于病毒感染及癌症的治疗具有潜在疗效,然而由于其在生物介质中的不稳定性和低穿透率,常需要修饰于一定的载体上,纳米粒子便是其良好的载体,修饰后可提高反义寡核苷酸的稳定性,研究应用FACS,MTT比色法,电子显微镜,原子力显微镜,细胞集落法研究MNP-端粒酶反义寡核苷酸复合物体外诱导HL-60细胞（人急性早幼粒细胞白血病细胞系）细胞凋亡情况,研究结果表明：通过MTT比色法检测可知不同的药物浓度对细胞的生长有明显的抑制影响;实验组细胞在诱导后于流式细胞术检测中产生了亚二倍体峰（凋亡峰）;通过集落形成及电镜观察都有明显的凋亡现象产生,因此认为MNP-端粒酶反义寡核苷酸复合物具有诱导HL-60细胞凋亡的作用。     

HPLC法分离2,4-二氯-5-甲基吡啶和2-氯-4-硝基-5-甲基吡啶

建立了一种用于分离2,4-二氯-5-甲基吡啶和2-氯-4-硝基-5-甲基吡啶的HPLC分析方法.液相色谱使用ODS-C18柱,以甲醇水=8020为流动相,紫外检测波长为254 m.样品线性范围50～500μg/mL.该法准确、快速、简便,可用于实际生产中间控制.     

旗传递5-(v,k,2)设计

如果一个非平凡的t-设计具有一个旗传递的自同构群,那么t≤6,并且它的自同构群是[(t+1)/2]齐次本原群.因此,一个旗传递5-(v,k,2)设计的自同构群是3-齐次本原置换群.利用3-齐次本原置换群分类定理,讨论了旗传递5-(v,k,2)设计的分类问题.通过分析5-(v,k,2)设计的组合数量关系和3-齐次本原置换群的性质,部分解决了旗传递5-(v,k,2)设计的分类.证明了如果群G是一个非平凡的5-(v,k,2)设计D的旗传递自同构群,那么Soc(G)=PSL(2,q),并且q=2e或3e.     

Synthesis, Characterization and Cyclization of 5-(2-methylthio -4-methyl-5-pyrimidinyl) -2,4-pentadiyne-1-ol Sorbate

合成了5-(2-硫甲基-4-甲基)-嘧啶基-戊二炔-1-醇山梨酸酯,并用IR、UV-vis、1H、13C、DEPT、gCOSY、gHSQC和gHMBC等对产物进行了表征.此化合物具有两个共轭系统,在gHMBC中检测到了五阶和六阶碳氢相关信号.在光热条件下,此化合物发生分子内环加成形成苯环结构.     

Isolation, characterization and functional analysis of a cdc48 homologue from tobacco BY-2 cells

The fission yeast Schizosaccharomyces pombe was used to identify genes from tobacco BY-2 cells that may play roles in cell cycle regulation. A cDNA encoding a protein homologous to the yeast CDC48 was isolated and the gene was designated as NtCDC48. The cDNA contains an open reading frame coding for a predicted protein of 808 amino acids which comprises of two typical ATPase modules (aa 245?374 and aa 518?646). Overexpression of NtCDC48 in tobacco BY-2 cells led to an increase in the mitotic index as well as to the formation of diffused mitotic spindles. NtCDC48-GFP fusion proteins are distributed ubiquitously through G1 to M phases, yet their subcellular localization varied regularly along with the cell cycle progression. These results indicate that NtCDC48 may play an important role in the regulation of cell cycle in BY-2 cells.     

Isolation, characterization and functional analysis of a cdc48 homologue from tobacco BY-2 cells

The fission yeast Schizosaccharomyces pombe was used to identify genes from tobacco BY-2 cells that may play roles in cell cycle regulation. A cDNA encoding a protein homologous to the yeast CDC48 was isolated and the gene was designated as NtCDC48 . The cDNA contains an open reading frame coding for a predicted protein of 808 amino acids which comprises of two typical ATPase modules (aa 245-374 and aa 518-646) . Overexpression of NtCDC48 in tobacco BY-2 cells led to an increase in the mitotic index as well as to the formation of diffused mitotic spindles. NtCDC48-GFP fusion proteins are distributed ubiquitously through Gl to M phases, yet their subcellular localization varied regularly along with the cell cycle progression. These results indicate that NtCDC48 may play an important role in the regulation of cell cycle in BY-2 cells.     

HPLC测定N-(3-溴苯基)-2-(4,6-二甲氧基嘧啶-2-基氧)苄胺

建立了测定N-(3-溴苯基)-2-(4,6-二甲氧基嘧啶-2-基氧)苄胺(BDM)水解反应的高效液相色谱分析方法。采用Hypersil ODS-C18反相色谱柱(4.6mm×250mm,5μm),流动相为甲醇-水(85∶15),检测波长249nm,流速为1mL/min,外标法定量测定。结果表明,BDM质量浓度在5～100mg/L范围内与峰面积呈良好的线性关系,加标准品的回收率为101.83%～105.70%,RSD 1.50%(n=6),并具有较好的精确度和重现性,该方法可用于测定该化合物的水解反应。试验证明BDM在酸性介质及较高的温度条件下能迅速水解,例如在50℃,pH值为1.3,反应24h后BDM完全水解。     

5－Br－PADAP与钍的显色反应研究

该文研究了５－Ｂｒ－ＰＡＤＡＰ在乙醇存在下与钍（Ⅳ）显色反应的适宜条件．实验结果证明在ｐＨ＝５．７０～６．１２范围内，钍（Ⅳ）与５－Ｂｒ－ＰＡＤＡＰ形成１：１深红色的配合物，其最大吸收峰位于５６４ｎｍ处．钍（Ⅳ）在０～２０μｇ／２５ｍＬ范围内符合比尔定律，由此计算其摩尔吸光系数ε＝４．３５×１０４Ｌ·ｍｏｌ（－１）·ｃｍ（－１），还对外来离子的干扰进行了研究，并进行了回收实验．