Associations between CYP1A1 and CYP2E1 polymorphisms and susceptibility to esophageal cancer in Chaoshan and Taihang areas of China

Purpose: To study the causes of esophageal cancer in Chaoshan and Taihang areas. Methods: By using gel-based DNA microarray genotyping method, four cancer-related polymorphisms including CYP1A1 m2, CYP1A1 m4, CYP2E1 Pst I and CYP2E1 Rsa I were studied with 565 (CYP1A1) or 482 (CYP2E1) cases and 468 (CYP1A1) or 466 (CYP2E1) controls. Results: For CYP1A1 m2, the mutant allele frequencies were 21.3% (Chaoshan) and 19.6% (Taihang), and OR for AG versus AA genotype (Chaoshan) was 1.855 (95% CI [1.227–2.805]). For CYP1A1 m4, no mutant allele was detectable. For CYP2E1 Pst I, the mutant allele frequencies were 27.3% (Chaoshan) and 29.4% (Taihang), and OR for GG versus CC genotype (Taihang) was 3.263 (95% CI [1.059–10.052]). For CYP2E1 Rsa I, the mutant allele frequencies were 27.3% (Chaoshan) and 29.6% (Taihang), and OR for CC versus TT genotype (Taihang) was 3.167 (95% CI [1.026–9.776]). Conclusion: The results suggest that AG genotype of CYP1A1 in Chaoshan area and GG (CC) genotype of CYP2E1 in Taihang area are significantly associated with esophageal cancer susceptibility.     

青海湖四种繁殖水鸟活动区域的研究

2006年4-9月,采用彩色标记、无线电遥测和卫星跟踪等方法,对青海湖四种繁殖水鸟斑头雁（Anser indicus）、棕头鸥（Larus brunnicephalus）、渔鸥（L．ichthyaetus）和鸬鹚（Phalacrocorax carbo）的活动区域进行了研究。采用“绳套法”捕捉了45只斑头雁,其中6只于4月安装了无线电发射器,6只于7月安装了卫星发射器;采用“拉网法”捕捉了104只棕头鸥,其中6只于4月安装了无线电发射器;采用“绳套法”捕捉了51只渔鸥,其中2只于4月安装了无线电发射器;采用“扣网法”捕捉了75只鸬鹚,其中6只于5月和6月安装了无线电发射器,4只于8月安装了卫星发射器。通过研究,获得了上述四种繁殖水鸟在青海湖的活动区域,即：斑头雁有3个主要的活动区域,棕头鸥有1个,渔鸥有4个,鸬鹚有2个。其中从鸬鹚岛、蛋岛、布哈河口、铁卜恰河口至泉湾区域是上述四种繁殖水鸟共有的活动区域,该区域也是春秋迁徙季节众多水鸟的重要取食地和停歇地。     

Glial progenitor-like phenotype in low-grade glioma and enhanced CD133-expression and neuronal lineage differentiation potential in high-grade glioma

Background

While neurosphere- as well as xenograft tumor-initiating cells have been identified in gliomas, the resemblance between glioma cells and neural stem/progenitor cells as well as the prognostic value of stem/progenitor cell marker expression in glioma are poorly clarified.

Methodology/Principal Findings

Viable glioma cells were characterized for surface marker expression along the glial genesis hierarchy. Six low-grade and 17 high-grade glioma specimens were flow-cytometrically analyzed for markers characteristics of stem cells (CD133); glial progenitors (PDGFRα, A2B5, O4, and CD44); and late oligodendrocyte progenitors (O1). In parallel, the expression of glial fibrillary acidic protein (GFAP), synaptophysin and neuron-specific enolase (NSE) was immunohistochemically analyzed in fixed tissue specimens. Irrespective of the grade and morphological diagnosis of gliomas, glioma cells concomitantly expressed PDGFRα, A2B5, O4, CD44 and GFAP. In contrast, O1 was weakly expressed in all low-grade and the majority of high-grade glioma specimens analyzed. Co-expression of neuronal markers was observed in all high-grade, but not low-grade, glioma specimens analyzed. The rare CD133 expressing cells in low-grade glioma specimens typically co-expressed vessel endothelial marker CD31. In contrast, distinct CD133 expression profiles in up to 90% of CD45-negative glioma cells were observed in 12 of the 17 high-grade glioma specimens and the majority of these CD133 expressing cells were CD31 negative. The CD133 expression correlates inversely with length of patient survival. Surprisingly, cytogenetic analysis showed that gliomas contained normal and abnormal cell karyotypes with hitherto indistinguishable phenotype.

Conclusions/Significance

This study constitutes an important step towards clarification of lineage commitment and differentiation blockage of glioma cells. Our data suggest that glioma cells may resemble expansion of glial lineage progenitor cells with compromised differentiation capacity downstream of A2B5 and O4 expression. The concurrent expression of neuronal markers demonstrates that high-grade glioma cells are endowed with multi-lineage differentiation potential in vivo. Importantly, enhanced CD133 expression marks a poor prognosis in gliomas.     

Purification and characterization of a type III photolyase from Caulobacter crescentus

The photolyase/cryptochrome family is a large family of flavoproteins that encompasses DNA repair proteins, photolyases, and cryptochromes that regulate blue-light-dependent growth and development in plants, and light-dependent and light-independent circadian clock setting in animals. Phylogenetic analysis has revealed a new class of the family, named type III photolyase, which cosegregates with plant cryptochromes. Here we describe the isolation and characterization of a type III photolyase from Caulobacter crescentus. Spectroscopic analysis shows that the enzyme contains both the methenyl tetrahydrofolate photoantenna and the FAD catalytic cofactor. Biochemical analysis shows that it is a bona fide photolyase that repairs cyclobutane pyrimidine dimers. Mutation of an active site Trp to Arg disrupts FAD binding with no measurable effect on MTHF binding. Using enzyme preparations that contain either both chromophores or only folate, we were able to determine the efficiency and rate of transfer of energy from MTHF to FAD.     

Smad3基因剔除小鼠特异性免疫功能的研究

目的　研究Smad3基因剔除小鼠的体液免疫和细胞免疫。方法　采用流式细胞仪对其细胞免疫和体液免疫进行检测 ;并且应用ELISA方法对IgG抗体的吸光度进行测定。结果　纯合型 (- - )小鼠CD8 、CD4 CD8 、IgG雌雄之间差异有显著性 ;CD4 、CD8 、CD3 、CD19 、IgG的值低于野生型 ;结论　CD4 CD8 的比值同野生型比较属于异常 (与人的范围比较 )。因此 ,为在人类免疫疾病研究方面选用该动物提供一定的参考价值     

黑鹅膏菌（Amanita fuliginea）毒素的HPLC初步分离鉴定

本文了用反相高效液相色谱法（ＨＰＬＣ）分离黑鹅膏实体内几种鹅膏毒素的结果,采用Ｃ１８液相柱,以不同浓度的０．０２ｍｏｌ／Ｌ乙酸铵－乙腈混合液为流动相,从黑鹅膏子产体中分离并鉴定出了６种毒素,每公斤干重含量分别为（ｍｍｏｌ）：α－毒伞肽：５．１９ｍｍｏｌ;β－毒伞肽;１．１７ｍｍｏｌ;ｐｈａｌｌｏｉｄｉｎ;１．５ｍｍｏｌ;ｐｈａｌｌａｃｉｄｉｎ;０．４０ｍｍｏｌ;ｐｈａｌｌｉｓｉｎ;０．２６ｍｍｏｌ     

几种不同鹅膏菌毒素对真核生物RNA聚合酶Ⅱ抑制作用的比较研究

用鹅膏菌属（Amanita）含α-毒伞肽的毒素粗提液培养新鲜绿豆,结果在36小时后,各种不同毒苗的毒素粗提液培养的绿豆生长情况有明显不同,用紫外吸收法测定蛋白质含量,发现毒素粗提液培养的绿豆细胞中蛋白质含量比蒸馏水培养的有明显下降,这表明α-毒伞肽的作用机理的确是通过抑制RNA聚合酶Ⅱ而寻致蛋白质合成减少。     

Reconstitution of the plant ubiquitination cascade in bacteria using a synthetic biology approach

Ubiquitination modulates nearly all aspects of plant life. Here, we reconstituted the Arabidopsis thaliana ubiquitination cascade in Escherichia coli using a synthetic biology approach. In this system, plant proteins are expressed and then immediately participate in ubiquitination reactions within E. coli cells. Additionally, the purification of individual ubiquitination components prior to setting up the ubiquitination reactions is omitted. To establish the reconstituted system, we co‐expressed Arabidopsis ubiquitin (Ub) and ubiquitination substrates with E1, E2 and E3 enzymes in E. coli using the Duet expression vectors. The functionality of the system was evaluated by examining the auto‐ubiquitination of a RING (really interesting new gene)‐type E3 ligase AIP2 and the ubiquitination of its substrate ABI3. Our results demonstrated the fidelity and specificity of this system. In addition, we applied this system to assess a subset of Arabidopsis E2s in Ub chain formation using E2 conjugation assays. Affinity‐tagged Ub allowed efficient purification of Ub conjugates in milligram quantities. Consistent with previous reports, distinct roles of various E2s in Ub chain assembly were also observed in this bacterial system. Therefore, this reconstituted system has multiple advantages, and it can be used to screen for targets of E3 ligases or to study plant ubiquitination in detail.     

藓类植物中国新记录种——无疣对齿藓

报道了对齿藓属中国新记录种——无疣对齿藓(Didymodon validus Limpr.)(新拟)。该种主要分布于欧洲和中亚。该种的主要特征为叶干燥时内卷或背弯,叶片较长,中肋突出叶尖呈长毛尖,叶细胞平滑无疣。该研究对无疣对齿藓的形态特征、地理分布进行了详细描述,将其与属内相似种进行了比较分析,并提供了该种的显微照片和形态线描图。     

MiRNA-145 suppresses lung adenocarcinoma cell invasion and migration by targeting N-cadherin

Objective

To investigate the roles of miR-145 in lung adenocarcinoma (LAC) and to clarify the regulation of N-cadherin by miR-145.

Results

In 57 paired clinical LAC tissues, diminished miR-145 was significantly correlated with the lymph node metastasis and was negatively correlated with N-cadherin mRNA level expression. Wound healing and transwell assays revealed a reduced capability of tumor metastasis induced by miR-145 in LAC. miR-145 negatively regulated the invasion of cell lines through targeting N-cadherin by directly binding to its 3′-untranslated region. Silencing of N-cadherin inhibited invasion and migration of LAC cell lines similar to miR-145 overexpression.

Conclusions

MiR-145 could inhibit invasion and migration of lung adenocarcinoma cell lines by directly targeting N-cadherin.