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931.
Characteristics of the microbial community in rhizosphere of Camptotheca acuminata cultured with exotic invasive plant Eupatorium adenophorum 总被引:1,自引:0,他引:1
ZU YuanGang GAO ChongYang WANG WenJie YANG FengJian LIU Ying WANG Min ZHAO YangGuo 《中国科学:生命科学英文版》2007,50(1):22-30
The traditional culture-dependent plate counting and culture-independent small-subunit-ribosomal RNA gene-targeted molecular techniques, Single-Strand Conformation Polymorphism (SSCP) and ter-minal Restriction Fragment Length Polymorphism (tRFLP) combined with 16S rDNA clone library were adopted to investigate the impacts of secretion from Camptotheca acuminata (abbreviated to Ca) roots on the quantities and structure of eukaryotic microbes and bacteria in the rhizosphere, and the possi-bility that Ca controls exotic invasive plant Eupatorium adenophorum (Ea). The counting results indi-cated that the number of bacteria increased in turn in rhizospheres of Ea, Ca-Ea mixed culture and Ca, while that of eukaryotic microbes decreased. PCR-SSCP profiles showed eukaryotic microbial bands (corresponding to biodiversity) in rhizosphere of Ea were more complex than those of Ca and CE. Meristolohmannia sp., Termitomyces sp. and Rhodophyllus sp. were the dominant populations in the rhizosphere of Ca. Bacterial terminal restriction fragments (TRFs) profiles showed no difference among three kinds of rhizospheres, and the sequences of the 16S rDNA clone library from Ca rhizospheres were distributed in 10 known phyla, in which phylum Proteobacteria were the absolute dominant group and accounted for 24.71% of the cloned sequences (δ-Proteobacteria accounted for up to 17.65%), and phyla Acidobacteria and Bacteroidetes accounted for 16.47% and 10.59% of the cloned sequences, respectively. In addition, high performance liquid chromatography detected a trace amount of camp-tothecin and hydroxycamptothecin in the rhizospheric soil of Ca and CE, but examined neither camp-tothecin nor hydroxycamptothecin in rhizospheric soil of Ea. Therefore, invasion and diffusion of Ea evidently depended on distinguishing the eukaryotic community structure, but not on that of the bac-terial pattern. Ca was able to alter the eukaryotic community structure of invasive Ea by secreting camptothecin and hydroxycamptothecin into rhizospheres, and may benefit the control of overspread of Ea. This study provided theoretical evidence for rhizospheric microbial aspects on substituting Ca for Ea. 相似文献
932.
Field cultivation experiments on white sesame (Sesamum indicum L.)seeds implanted with low-energy C ion showed that different dosages of C ion implantation produce different biological effects.Sesame plants in 6 different dosage groups with C ion density respectively at 1×1011,1×1012,1×1015,5×1015,1×1016,5×1016 ion/cm2 were superior to the control group in plant height,leaf number,stalk diameter and leaf size.Further,sesame plants in these groups flower and seed earlier than those in the control group,and single plant yield also increased.Of all the groups,the 5×1015 ion/cm2 dosage group yielded the best effect,whereas the 1×1017/cm2 dosage group showed an evident inhibitory effect of ion implantation on the germination and growth of the sesame seeds. 相似文献
933.
He H Zhao Y Chen X Zheng Y Wu X Wang R Li T Yu Q Jing J Ma L Ren W Han D Wang G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,855(2):145-151
A simple, accurate, precise, specific and reproducible high-performance liquid chromatography (HPLC) method was developed for determination of trans-polydatin, a natural strong anti-oxidative compound, in rat plasma and cell suspension. The assay procedure involved simple liquid-liquid extraction, the supernatant liquid was added an equal volume of water to avoid solvent effect. The detection of the analyte peak was achieved by monitoring the eluate using a UV detector set at 303 nm. The analysis used a Hypersil ODS2 C18 column (5 microm, 4.6 mm x 250 mm) and methanol/distilled water as the mobile phase (flow rate=1 mL/min). A total analytical run was achieved within 6.0 min and calibration curve was linear over a wide concentration range of 0.25-40 microg/mL for plasma sample and 1.0-500 microM for cell suspension, the coefficients of correlation were 0.9997 and 0.9999 or better, respectively. There was 80.7+/-7.86%, 96.8+/-3.20% and 102.7+/-9.72% recovery from 0.5, 10, and 40 microg/mL plasma samples, respectively. Intra- and inter-batch accuracy and precision were acceptable for the both matrices. The RSD of intra- and inter-day assay variations were all less than 10%. Both analyte and IS were stable in the battery of stability studies, freeze-thaw cycles. The described assay method was applied to pharmacokinetic studies in rats and a human colon adenocarcinoma cell line (Caco-2) successfully. The application of the assay to determine the pharmacokinetic is described. 相似文献
934.
935.
Sun W Xing B Sun Y Du X Lu M Hao C Lu Z Mi W Wu S Wei H Gao X Zhu Y Jiang Y Qian X He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p = 0.01) in tumor samples, whereas 158 spots were down-regulated (ratio = -2, p = 0.01). Seventy-one gene products were identified among these spots. Members of the heat shock protein 70 and 90 families were simultaneously up-regulated, whereas metabolism-associated proteins were decreased in HCC samples. The down-regulation of mitochondrial and peroxisomal proteins in these results suggested loss of special organelle functions during HCC carcinogenesis. Four metabolic enzymes involved in the methylation cycle in the liver were down-regulated in HCC tissues, indicating S-adenosylmethionine deficiency in HCC. Two gene products, glyceraldehyde-3-phosphate dehydrogenase and formimidoyltransferase-cyclodeaminase, were identified from inversely altered spots, suggesting that different isoforms or post-translational modifications of these two proteins might play different roles in HCC. For the first time, the overexpression of Hcp70/Hsp90-organizing protein and heterogeneous nuclear ribonucleoproteins C1/C2 in HCC tissues was confirmed by Western blot and then by immunohistochemistry staining in 70 HCC samples, suggesting their potential as protein tumor markers. In summary, we profiled proteome alterations in HCC tissues, and these results may provide useful insights for understanding the mechanism involved in the process of HCC carcinogenesis. 相似文献
936.
Antisense RNA-mediated suppression of Bmi-1 gene expression inhibits the proliferation of lung cancer cell line A549 总被引:6,自引:0,他引:6
The oncogene Bmi-1 regulates cell proliferation and senescence. It is reported that it controlled the self-renewal of leukemic and breast cancer stem cell and was overexpressed in some solid tumors and hematologic malignancies. In this study, the effects of inactivation of Bmi-1 mediated by a plasmid-expressing antisense Bmi-1 RNA on the proliferation of lung cancer cell line A549 were investigated. As a result, when the plasmid was stably introduced into the cell line, the Bmi-1 protein level was specifically downregulated, and the cell proliferation was significantly inhibited as shown by the cell growth curve and colony forming assay. The cells were found mostly in the phase of G(0)/G(1) and cells in S phase were significantly decreased. Our results suggest that targeting Bmi-1 might be a therapeutic potential for the treatment of non-small-cell lung cancer. 相似文献
937.
Dynamical systems for discovering protein complexes and functional modules from biological networks 总被引:1,自引:0,他引:1
Li W Liu Y Huang HC Peng Y Lin Y Ng WK Ong KL 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2007,4(2):233-250
Recent advances in high throughput experiments and annotations via published literature have provided a wealth of interaction maps of several biomolecular networks, including metabolic, protein-protein, and protein-DNA interaction networks. The architecture of these molecular networks reveals important principles of cellular organization and molecular functions. Analyzing such networks, i.e., discovering dense regions in the network, is an important way to identify protein complexes and functional modules. This task has been formulated as the problem of finding heavy subgraphs, the heaviest k-subgraph problem (k-HSP), which itself is NP-hard. However, any method based on the k-HSP requires the parameter k and an exact solution of k-HSP may still end up as a "spurious" heavy subgraph, thus reducing its practicability in analyzing large scale biological networks. We proposed a new formulation, called the rank-HSP, and two dynamical systems to approximate its results. In addition, a novel metric, called the standard deviation and mean ratio (SMR), is proposed for use in "spurious" heavy subgraphs to automate the discovery by setting a fixed threshold. Empirical results on both the simulated graphs and biological networks have demonstrated the efficiency and effectiveness of our proposal 相似文献
938.
以母本平邑甜茶1株、父本扎矮山定子1株、皱叶矮生型株系(F1)6株及其自然授粉后代实生苗(F2)15株为试材,采用聚丙烯酰胺凝胶电泳法研究叶片过氧化物酶同工酶谱的异同。结果表明:皱叶矮生型株系叶片的过氧化物酶同工酶酶谱共有10条酶带,R f值范围0.18~0.90,各植株间的酶带数量基本一致,只有强弱不同,与平邑甜茶酶谱的差异也很小。在皱叶矮生型株系的后代实生苗叶片中,除15 a单株有16条酶带外,其他实生苗的过氧化物酶同工酶酶谱约有10条酶带,但株间差异明显,R f值范围0.18~0.84。不同树龄平邑甜茶叶片的酶谱一致性较好。 相似文献
939.