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The mechanism of calcium uptake, translocation and accumulation in Poaceae has not yet been fully understood. To address this issue, we conducted genome-wide comparative in silico analysis of the calcium (Ca2+) transporter gene family of two crop species, rice and sorghum. Gene annotation, identification of upstream cis-acting ele- ments, phylogenetic tree construction and syntenic mapping of the gene family were performed using several bio- informatics tools. A total of 31 Ca2+ transporters, distributed on 9 out of 12 chromosomes, were predicted from rice genome, while 28 Ca2+ transporters predicted from sorghum are distributed on all the chromosomes except chromosome 10 (Chr 10). Interestingly, most of the genes on Chr 1 and Chr 3 show an inverse syntenic relation- ship between rice and sorghum. Multiple sequence alignment and motif analysis of these transporter proteins re- vealed high conservation between the two species. Phylogenetic tree could very well identify the subclasses of channels, ATPases and exchangers among the gene family. The in silico cis-regulatory element analysis suggested diverse functions associated with light, stress and hormone responsiveness as well as endosperm- and meris- tem-specific gene expression. Further experiments are warranted to validate the in silico analysis of the predicted transporter gene family and elucidate the functions of Ca2+ transporters in various biological processes. 相似文献
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eQTL Explorer: integrated mining of combined genetic linkage and expression experiments 总被引:1,自引:0,他引:1
Mueller M Goel A Thimma M Dickens NJ Aitman TJ Mangion J 《Bioinformatics (Oxford, England)》2006,22(4):509-511
The development of computational resources to visualize and explore data from combined genome-wide expression and linkage studies is essential for the development of testable hypotheses. eQTL Explorer stores expression profiles, linkage data and information from external sources in a relational database and enables simultaneous visualization and intuitive interpretation of the combined data via a Java graphical interface. eQTL Explorer provides a new and powerful tool to interrogate these very large and complex datasets. 相似文献
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Developing novel combined-modality therapeutic approaches based on understanding of the involvement of redox biology in apoptosis of malignant cells is a promising approach for improving clinical responses in B-cell lymphoma and multiple myeloma. Therapeutic modalities that generate reactive oxygen species (i.e., radiation, photodynamic therapy, and specific chemotherapeutic drugs) have been shown to be selectively cytotoxic to malignant B-cells. In this review, we will discuss agents that induce apoptosis in B-cell tumors by oxidative stress. Subsequently, a novel biochemical rationale (based on fundamental differences in cancer vs. normal cell oxidative metabolism) for combining oxidative stressors with radiotherapy and chemotherapy, that may lead to designing of more effective treatment strategies for B-cell malignancies, will be discussed. Besides providing potential curative benefit, such novel therapies could also selectively target and inhibit the emergence of drug-resistance in tumor cells, which is a major determinant of treatment failure in many B-cell malignancies. 相似文献
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Pentoxifylline (PTX), a methylxanthine derivative is a non-steroidal immunomodulating agent with unique hemorheologic properties. It is used in the treatment of intermittent claudication as it increases the amount of oxygen reaching tissues by increasing the flexibility of red blood cells. Recently, it has also shown to exhibit anti-metastatic and anti-angiogenic activities in B16F10 melanoma cells both in vitro as well as in vivo. As per the reports, the choice of drug in the treatment of breast cancer is paclitaxel, but the major limitation is its toxicity. However, the effects of PTX on metastatic processes in breast cancer are not currently known. Therefore, in this study, we have examined the effect of PTX in MDA-MB-231 human breast cancer cells. The MTT assay showed dose- and time-dependent decreases in cellular proliferation. The non-toxic concentration of PTX selected were 1, 2.5 and 5 mM for 24 h. PTX induced a G0-G1 cell-cycle arrest leading to apoptosis. Further, it affected adhesion to both the matrigel and collagen type-IV in a time- and dose-dependent manner. The PTX impeded the migration of MDA-MB-231 cells and also decreased the activities of both MMP-2 and MMP-9. Thus, PTX at non-toxic doses affected cellular proliferation, adhesion, migration and invasion. These results demonstrate its anti-metastatic effect on MDA-MB-231 cells, and further studies need to be carried out to understand the mechanism of action. 相似文献
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M. K. Sharma A. K. Goel L. Singh V. K. Rao 《World journal of microbiology & biotechnology》2006,22(11):1155-1159
Environmental surveillance for the presence of Vibrio cholerae O1 is of utmost importance for the effective public health protection of cholera. In the present study, an amperometric immunosensor was developed for detection of Vibrio cholerae in environmental samples by using disposable screen-printed electrodes (SPEs). For this purpose, the experiments done include fabrication of SPEs by using carbon ink, electrochemical characterization of electrodes, optimization of dilutions of antibodies and immobilization of antibody. V. cholerae O1 bacteria were spiked in various environmental water samples in known number. The seeded samples were filtered through a 0.22 μm membrane, and the filters enriched in alkaline peptone water for 6 h and then used directly for detection of V. cholerae using the immunosensor. The immunosensor could detect as few as 8 c.f.u./ml in hand-pump water (ground water) and seawater, and 80 c.f.u./ml in sewer water and tap water. The total time taken in this detection assay was 55 min. Thus, the proposed method is simple and can be used for environmental monitoring of V.␣cholerae. 相似文献