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941.
942.
943.
Kaivalya M Nageshwar Rao BN Satish Rao BS 《Journal of biochemical and molecular toxicology》2011,25(2):108-116
Mangiferin (MGN), a dietary C-glucosylxanthone present in Mangifera indica, is known to possess a spectrum of beneficial pharmacological properties. This study demonstrates antigenotoxic potential of MGN against mercuric chloride (HgCl2)-induced genotoxicity in HepG2 cell line. Treatment of HepG2 cells with various concentrations of HgCl2 for 3 h caused a dose-dependent increase in micronuclei frequency and elevation in DNA strand breaks (olive tail moment and tail DNA). Pretreatment with MGN significantly (p < 0.01) inhibited HgCl2 -induced (20 μM for 30 h) DNA damage. An optimal antigenotoxic effect of MGN, both in micronuclei and comet assay, was observed at a concentration of 50 μM. Furthermore, HepG2 cells treated with various concentrations of HgCl2 resulted in a dose-dependent increase in the dichlorofluorescein fluorescence, indicating an increase in the generation of reactive oxygen species (ROS). However, MGN by itself failed to generate ROS at a concentration of 50 μM, whereas it could significantly decrease HgCl2 -induced ROS. Our study clearly demonstrates that MGN pretreatment reduced the HgCl2-induced DNA damage in HepG2 cells, thus demonstrating the genoprotective potential of MGN, which is mediated mainly by the inhibition of oxidative stress. 相似文献
944.
Ramaswamy M Cruz AC Cleland SY Deng M Price S Rao VK Siegel RM 《Cell death and differentiation》2011,18(4):712-720
Elimination of autoreactive CD4+ T cells through the death receptor Fas/CD95 is an important mechanism of immunological self-tolerance. Fas deficiency results in systemic autoimmunity, yet does not affect the kinetics of T-cell responses to acute antigen exposure or infection. Here we show that Fas and TCR-induced apoptosis are largely restricted to CD4+ T cells with an effector memory phenotype (effector memory T cells (TEM)), whereas central memory and activated naïve CD4+ T cells are relatively resistant to both. Sensitivity of TEM to Fas-induced apoptosis depends on enrichment of Fas in lipid raft microdomains, and is linked to more efficient formation of the Fas death-inducing signaling complex. These results explain how Fas can cull T cells reactive against self-antigens without affecting acute immune responses. This work also identifies Fas-induced apoptosis as a possible immunotherapeutic strategy to eliminate TEM linked to the pathogenesis of a number of autoimmune diseases. 相似文献
945.
A problem of paramount importance that has attracted the attention of environmental biologists is the discharge of highly colored effluents into the environment by various industries, which use a wide range of synthetic dyes. The existing chemical methods for dye degradation are not only expensive but also contributes to secondary pollution due to high dose of the chemicals used. Hence an alternative is to exploit the potential of microorganisms to alleviate this problem. The current paper deals with the isolation, characterization, and sugar utilization for better growth of Aspergillus flavus, a marine fungus from the Bay of Bengal. The goal is to assess the bioremediation potential of a variety of synthetic, paper mill, and color photography dyes. A correlation between the amount of sugar used, biomass, and quality of protein produced was observed. This fungus is capable of reducing between 80% and 90% of synthetic dyes and 100% color photography effluents within 3 to 7 days, and 8 days, respectively. Significant effect of carbon sources was observed in the decolorization of the synthetic dye crystal violet, up to 90% in 3 to 7 days, by Aspergillus flavus. The organism showed better growth with fructose as the sole carbon source for the least sugar consumption. Therefore, this fungus can be used as an economical and eco-friendly tool to minimize the pollution by industries to a significant extent. 相似文献
946.
This review elaborates on recent insights gained on the dynamic aspects of interactions between pathogen and the host intracellular machinery in tuberculosis infection. In addition we will also discuss the utility of adopting a systems biology approach, both for a better understanding of TB biology, and for the development of more effective ways for disease management. 相似文献
947.
Modulation of ROS/MAPK signaling pathways by okadaic acid leads to cell death via,mitochondrial mediated caspase-dependent mechanism 总被引:1,自引:0,他引:1
Ravindran J Gupta N Agrawal M Bala Bhaskar AS Lakshmana Rao PV 《Apoptosis : an international journal on programmed cell death》2011,16(2):145-161
Okadaic acid (OA) is a specific and potent protein phosphatase inhibitor and tumor promoter. The present study establishes the role of reactive oxygen species (ROS) and mitogen activated protein kinases in cell death induced by okadaic acid. The study showed that okadaic acid is cytotoxic at 10 nM with an IC50 of 100 nM in U-937 cells. The CVDE assay and mitochondrial dehydrogenase assay showed a time dependent cytotoxicity. The phase contrast visualization of the OA treated cells showed the apoptotic morphology and was confirmed with esterase staining for plasma membrane integrity. OA activated caspases-7, 9 and 3, PARP cleavage and induced nuclear damage in a time and dose dependent manner. Compromised mitochondrial membrane potential, release of cytochrome-c and apoptosis inducing factor confirms the involvement of mitochondria. A time dependent decrease in glutathione levels and a dose dependent increase in ROS with maximum at 30 min were observed. ROS scavenger-N-acetyl cysteine, mitochondrial stabilizer-cyclosporin-A, and broad spectrum caspase inhibitor Z-VAD-FMK inhibited the OA induced caspase-3 activation, DNA damage and cell death but caspase-8 inhibitor had no effect. OA activated p38 MAPK and JNK in a time dependent manner, but not ERK½. MAP kinase inhibitors SB203580, SP600125 and PD98059 confirm the role of p38 MAPK and JNK in OA induced caspase-3 activation and cell death. Over all, our results indicate that OA induces cell death by generation of ROS, and activation of p38 MAPK and JNK, and executed through mitochondrial mediated caspase pathway. 相似文献
948.
Biswas A Rao R Umashankar S Mynampati KC Reuben S Parab G Swarup S 《Bioinformatics (Oxford, England)》2011,27(11):1585-1586
SUMMARY: Data processing, analysis and visualization (datPAV) is an exploratory tool that allows experimentalist to quickly assess the general characteristics of the data. This platform-independent software is designed as a generic tool to process and visualize data matrices. This tool explores organization of the data, detect errors and support basic statistical analyses. Processed data can be reused whereby different step-by-step data processing/analysis workflows can be created to carry out detailed investigation. The visualization option provides publication-ready graphics. Applications of this tool are demonstrated at the web site for three cases of metabolomics, environmental and hydrodynamic data analysis. AVAILABILITY: datPAV is available free for academic use at http://www.sdwa.nus.edu.sg/datPAV/. 相似文献
949.
Rao MS 《Cell Stem Cell》2011,9(1):7-10
The cell therapy branch of the regenerative medicine field has been innovative in developing new models of delivery and development and identifying alternative sources of funding. We discuss the implications of these changes for pharmaceutical companies and the opportunities they offer to a new entrepreneur. 相似文献
950.
Prakash P. Kumar Ian M. Turner A. Nagaraja Rao K. Arumuganathan 《Plant biotechnology reports》2011,5(4):317-322
We determined the nuclear DNA content (genome size) of over 35 accessions each of bamboo and rattan species from Southeast
Asia. The 2C DNA per nucleus was quantified by flow cytometry. The fluorescence of nuclei isolated from the leaves and stained
with propidium iodide was measured. The genome size of the bamboo species examined was between 2.5 and 5.9 pg DNA per 2C nucleus.
The genome size of the rattan species examined ranged from 1.8 to 10.5 pg DNA per 2C nucleus. This information will be useful
for scientists working in diverse areas of plant biology such as biotechnology, biodiversity, genome analysis, plant breeding,
physiology and molecular biology. Such data may be utilized to attempt to correlate the genome size with the ploidy status
of bamboo species in cases where ploidy status has been reported. 相似文献