不同土壤水分和养分条件下喜旱莲子草与同属种生长状况的比较研究

喜旱莲子草(Alternanthera philoxeroides)入侵已在中国造成巨大的生态和经济损失。为揭示喜旱莲子草成功入侵的生态机制并预测其种群扩张趋势及其与环境因子的关系, 作者比较了喜旱莲子草与其同属的外来弱入侵种刺花莲子草(A. pungens)以及土著种莲子草(A. sessilis)在不同土壤水分、养分条件下的生长状况。结果显示: 在高水高肥条件下, 喜旱莲子草的生物量要高于刺花莲子草和莲子草, 而在低水低肥条件下却不如这两个同属种; 弱入侵种刺花莲子草在低水条件下的生物量要高于强入侵种喜旱莲子草和土著种莲子草, 说明植物的入侵性受环境条件的影响。另外, 强入侵种喜旱莲子草形态学性状的可塑性较高, 在各种条件下都具有较高的比叶面积, 暗示这两个指标可作为莲子草属外来植物入侵性的预测指标。     

Quantitative determination of helicid in rat biosamples by liquid chromatography electrospray ionization mass spectrometry

A simple liquid chromatography electrospray ionization mass spectrometry (LC–ESI–MS) method with highly improved sensitivities for the determination of helicid in rat bile, urine, feces and most tissues was developed. The tissues and feces were firstly homogenized mechanically using deionized water as the media. Bile, urine, tissues and feces homogenates were extracted by liquid–liquid extraction with n-butyl alcohol for sample preparation. The subsequent analysis procedures were performed on a Shimadzu LCMS2010A system (electrospray ionization single quadrupole mass analyzer). A Luna C₁₈ column (150 mm × 2.00 mm, 5 μm) was used as the analytical column, while a mixture of acetonitrile and ammonium chloride water solution was used as the mobile phase. The proportions of mobile phase were changed timely according to gradient programs. Chlorinated adducts of molecular ions [M+Cl]^? at m/z 319.00 and 363.05 were used to quantify helicid and bergeninum (internal standard), respectively. The method was validated to be accurate, precise and rugged with good linearity. The proposed method was successfully applied to the preclinical tissue distribution and excretion studies of helicid in rats.     

灰仓鼠重要内脏器官生长指数及其变化

对室内培育的灰仓鼠进行同一季节不同年龄段和同一年龄段不同季节某些器官的测量。结果显示, 在初生至25 d 的高速生长期, 体重与肝脏、心脏、肺、脾脏和肾的生长非常接近Huxley 的相对生长公式Y = b x^k , 其回归方程分别为: 肝脏Y = 0.013 47 x^{1.515 9} ; 心脏Y = 0.000 18 x^2.163 ; 肺Y = 0.028 48 x^{0.798 2} ; 脾脏Y = 0.000 24 x^{1.583 6} ; 肾脏Y = 0.000 2418 x^{2.310 4} , 并高度相关。睾丸的回归方程在60 日内与Y = b x^k公式非常拟合, Y = 0.000 0108 x^{3.049 4} , r = 0.989 9。除性腺外, 肝脏、心脏、肺、脾脏和肾脏的比值最高值均在25 d 之前。在性成熟期不同年龄段, 性腺比值较稳定, 其它器官比值在性别和年龄段有显著性差异, 雌性普遍高于雄性。在10 月龄不同季节, 只有体重和睾丸比值有显著性差异(7 月最高) , 表示在不同季节利用相近体重比较器官指数差异应将年龄因素作为重要参考依据。     

Proteomic analysis of differentially expressed proteins in Penaeus vannamei hemocytes upon Taura syndrome virus infection

To understand molecular responses of crustacean hemocytes to virus infection, we applied 2-DE proteomics approach to investigate altered proteins in hemocytes of Penaeus vannamei during Taura syndrome virus (TSV) infection. At 24 h postinfection, quantitative intensity analysis and nano-LC-ESI-MS/MS revealed 11 forms of 8 proteins that were significantly up-regulated, whereas 9 forms of 5 proteins were significantly down-regulated in the infected shrimps. These altered proteins play important roles in host defense (hemocyanin, catalase, carboxylesterase, transglutaminase, and glutathione transferase), signal transduction (14-3-3 zeta), carbohydrate metabolism (acetylglucosamine pyrophosphorylase), cellular structure and integrity (beta-tubulin, beta-actin, tropomyosin, and myosin), and ER-stress response (protein disulfide isomerase). Semiquantitative RT-PCR and Western blot analysis confirmed the upregulation of 14-3-3 at both mRNA and protein levels. Interestingly, several altered protein spots were identified as fragments of hemocyanin. Mass spectrometric analysis showed that the hemocyanin spots at acidic and basic regions represented the C- and N-terminal hemocyanin fragments, respectively. As three-quarters of C-terminal fragments were up-regulated, whereas two-thirds of N-terminal hemocyanin fragments were down-regulated, we therefore hypothesize that C- and N-terminal hemocyanin fragments may have differential roles in hemocytes. Further investigation of these data may lead to better understanding of the molecular responses of crustacean hemocytes to TSV infection.     

关于几种避孕植物药的药理初筛及成份预试

本文对云南滇西地区民间用于避孕和绝育秘方中的槌果藤,野花椒寄生、花椒寄生、螃蟹树寄生、鸡矢藤及野花椒的醇提取物进行了小鼠最大耐受量测定及小鼠抗生育实验,结果表明,花椒寄生、螃蟹树寄生的醇提取物具有明显抗生育活性,槌果藤也具有一定的抗生育作用。此外,还对槌果藤、野花椒寄生进行了化学成份预试。     

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.     

Integrated analysis of multiple data sources reveals modular structure of biological networks

It has been a challenging task to integrate high-throughput data into investigations of the systematic and dynamic organization of biological networks. Here, we presented a simple hierarchical clustering algorithm that goes a long way to achieve this aim. Our method effectively reveals the modular structure of the yeast protein-protein interaction network and distinguishes protein complexes from functional modules by integrating high-throughput protein-protein interaction data with the added subcellular localization and expression profile data. Furthermore, we take advantage of the detected modules to provide a reliably functional context for the uncharacterized components within modules. On the other hand, the integration of various protein-protein association information makes our method robust to false-positives, especially for derived protein complexes. More importantly, this simple method can be extended naturally to other types of data fusion and provides a framework for the study of more comprehensive properties of the biological network and other forms of complex networks.     

Activation of STAT6 by STING is critical for antiviral innate immunity

STAT6 plays a prominent role in adaptive immunity by transducing signals from extracellular cytokines. We now show that STAT6 is required for innate immune signaling in response to virus infection. Viruses or cytoplasmic nucleic acids trigger STING (also named MITA/ERIS) to recruit STAT6 to the endoplasmic reticulum, leading to STAT6 phosphorylation on Ser(407) by TBK1 and Tyr(641), independent of JAKs. Phosphorylated STAT6 then dimerizes and translocates to the nucleus to induce specific target genes responsible for immune cell homing. Virus-induced STAT6 activation is detected in all cell-types tested, in contrast to the cell-type specific role of STAT6 in cytokine signaling, and Stat6(-/-) mice are susceptible to virus infection. Thus, STAT6 mediates immune signaling in response to both cytokines at the plasma membrane, and virus infection at the endoplasmic reticulum.     

Fe- and S-Metabolizing Microbial Communities Dominate an AMD-Contaminated River Ecosystem and Play Important Roles in Fe and S Cycling

Indigenous Fe- and S-metabolizing bacteria play important roles both in the formation and the natural attenuation of acid mine drainage (AMD). Due to its low pH and Fe-S-rich waters, a river located in the Dabaoshan Mine area provides an ideal opportunity to study indigenous Fe- and S-metabolizing microbial communities and their roles in biogeochemical Fe and S cycling. In this work, water and sediment samples were collected from the river for physicochemical, mineralogical, and microbiological analyses. Illumina MiSeq sequencing indicated higher species richness in the sediment than in the water. Sequencing also found that Fe- and S-metabolizing bacteria were the dominant microorganisms in the heavily and moderately contaminated areas. Fe- and S-metabolizing bacteria found in the water were aerobes or facultative anaerobes, including Acidithiobacillus, Acidiphilium, Thiomonas, Gallionella, and Leptospirillum. Fe- and S-metabolizing bacteria found in the sediment belong to microaerobes, facultative anaerobes, or obligatory anaerobes, including Acidithiobacillus, Sulfobacillus, Thiomonas, Gallionella, Geobacter, Geothrix, and Clostridium. Among the dominant genera in the sediment, Geobacter and Geothrix were rarely detected in AMD-contaminated natural environments. Canonical correspondence analysis indicated that pH, S, and Fe concentration gradients were the most important factors in structuring the river microbial community. Moreover, a scheme explaining the biogeochemical Fe and S cycling is advanced in light of the Fe and S species distribution and the identified Fe- and S-metabolizing bacteria.