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41.
Ping Su Vishnu Priya Veeraraghavan Surapaneni Krishna Mohan Wang Lu 《Journal of biochemical and molecular toxicology》2019,33(12)
Zingerone (ZO), an active phenolic agent derived from Zingiber officinale (Ginger), has many pharmacological properties such as antioxidant, antiangiogenic, and antitumor. However, its potential value in cancer and the mechanism by which ZO wields its therapeutic effects remain obscure. Therefore, in this current study, we explored the effects of ZO on suppressing cell proliferation and enhancing apoptosis in colon cancer cells (HCT116). Our results indicated that ZO significantly enhances the production of reactive oxygen species, lipid peroxidation (thiobarbituric acid reactive substance [TBARS]), and loss of cell viability; and reduces mitochondrial membrane potential and antioxidant levels (SOD, CAT, and GSH) in ZO‐treated HCT116 cells in a dose‐dependent (2.5, 5, and 10 µM) manner. Furthermore, ZO induces oxidative stress‐mediated apoptosis as evidenced by apoptotic morphological changes predicted by AO/EtBr, Hoechst staining and further confirmed by comet assay. Moreover, immunoblotting techniques showed that ZO treatment effectively enhances Bax, caspase‐9, and caspase‐3 expressions and decreases the expression of Bcl‐2 in colon cancer cells. Together, our results evidenced that the antitumor effects of ZO reduce cell proliferation and stimulate apoptosis through modulating pro‐ and antiapoptotic molecular events in HCT116 colon cancer cells. Therefore, based on our findings, ZO may be used as a therapeutic agent for the treatment of colon cancer. 相似文献
42.
M ohan , K. 1985. Mycobacterium senegalense from bovines in Eastern Nigeria. Journal of Applied Bacteriology 59 , 277–281.
Detailed characteristics of three mycobacterial strains sharing important properties of Mycobacterium senegalense are described. Their physiological properties were compared with those of a typical M. senegalense strain described by Chamoiseau (1979), six strains of M. senegalense and one typical strain of M. fortuitum from the culture collection of Institute of Microbiology, Rutgers. The three Nigerian strains exhibited minor variations in their physiological properties when compared with other strains of M. senegalense . Unlike the strain of Chamoiseau the Nigerian strains did not utilize benzoate or citrate. The strains were also different from the other six strains of M. senegalense by utilizing trehalose and in failing to produce acid in mannitol. Unlike earlier isolates of M. senegalense the Nigerian strains were not from cases of bovine farcy but from cases with pathological manifestations of pulmonary tuberculosis. They appeared to be intermediate strains between M. senegalense and M. fortuitum . These results raise doubts on the justification for giving specific rank to M. senegalense . 相似文献
Detailed characteristics of three mycobacterial strains sharing important properties of Mycobacterium senegalense are described. Their physiological properties were compared with those of a typical M. senegalense strain described by Chamoiseau (1979), six strains of M. senegalense and one typical strain of M. fortuitum from the culture collection of Institute of Microbiology, Rutgers. The three Nigerian strains exhibited minor variations in their physiological properties when compared with other strains of M. senegalense . Unlike the strain of Chamoiseau the Nigerian strains did not utilize benzoate or citrate. The strains were also different from the other six strains of M. senegalense by utilizing trehalose and in failing to produce acid in mannitol. Unlike earlier isolates of M. senegalense the Nigerian strains were not from cases of bovine farcy but from cases with pathological manifestations of pulmonary tuberculosis. They appeared to be intermediate strains between M. senegalense and M. fortuitum . These results raise doubts on the justification for giving specific rank to M. senegalense . 相似文献
43.
Vashni Gramany Algasan Govender Krishna Bisetty Suren Singh Kugenthiren Permaul 《Journal of biomolecular structure & dynamics》2016,34(8):1681-1692
The aim of this study was to clone, express, and characterize a β-xylosidase (Tlxyn1) from the thermophilic fungus Thermomyces lanuginosus SSBP in Pichia pastoris GS115 as well as analyze optimal activity and stability using computational and experimental methods. The enzyme was constitutively expressed using the GAP promoter and secreted into the medium due to the alpha-mating factor secretion signal present on the expression vector pBGPI. The 1276 bp gene consists of an open reading frame that does not contain introns. A 12% SDS–PAGE gel revealed a major protein band at an estimated molecular mass of 50 kDa which corresponded to zymogram analysis. The three-dimensional structure of β-xylosidase was predicted, and molecular dynamics simulations at different ranges of temperature and pH were performed in order to predict optimal activity and folding energy. The results suggested a strong conformational temperature and pH dependence. The recombinant enzyme exhibited optimal activity at pH 7 and 50°C and retained 80% activity at 50°C, pH 7 for about 45 min. This is the first report of the cloning, functional expression, and simulations study of a β-xylosidase from Thermomyces species in a fungal host. 相似文献
44.
45.
S. Hari Krishna K. C. Sekhar Rao J. Suresh Babu D. Srirami Reddy S. Hari Krishna 《Bioprocess and biosystems engineering》2000,22(5):467-470
High yielding mutant strain, Trichoderma reesei QM-9414, was employed for the cellulase enzyme production. Enzyme production conditions (pH, inoculum age and concentration, and organic supplements) were optimized. The ability of partially purified enzyme to hydrolyze various regionally abundant lignocellulosic raw materials was studied. Enzymatic hydrolysis conditions (temperature, pH, enzyme and substrate concentrations) were optimized. Temperature 50v°C, pH 4.5, enzyme concentration 40 FPU/g substrate and substrate concentration 2.5% were found to be optimum for the maximum yields of sugars. #-glucosidase supplementation was found to increase both the sugar yield and hydrolysis rate, and shorten the reaction time significantly. 相似文献
46.
Krishna M. Boini Min Xia Justin M. Abais Guangbi Li Ashley L. Pitzer Todd W.B. Gehr Yang Zhang Pin-Lan Li 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
Inflammasome, an intracellular inflammatory machinery, has been reported to be involved in a variety of chronic degenerative diseases such as atherosclerosis, autoinflammatory diseases and Alzheimer's disease. The present study hypothesized that the formation and activation of inflammasomes associated with apoptosis associated speck-like protein (ASC) are an important initiating mechanism resulting in obesity-associated podocyte injury and consequent glomerular sclerosis. To test this hypothesis, Asc gene knockout (Asc−/−), wild type (Asc+/+) and intrarenal Asc shRNA-transfected wild type (Asc shRNA) mice were fed a high fat diet (HFD) or normal diet (ND) for 12 weeks to produce obesity and associated glomerular injury. Western blot and RT-PCR analyses demonstrated that renal tissue Asc expression was lacking in Asc−/− mice or substantially reduced in Asc shRNA transfected mice compared to Asc+/+ mice. Confocal microscopic and co-immunoprecipitation analysis showed that the HFD enhanced the formation of inflammasome associated with Asc in podocytes as shown by colocalization of Asc with Nod-like receptor protein 3 (Nalp3). This inflammasome complex aggregation was not observed in Asc−/− and local Asc shRNA-transfected mice. The caspase-1 activity, IL-1β production and glomerular damage index (GDI) were also significantly attenuated in Asc−/− and Asc shRNA-transfected mice fed the HFD. This decreased GDI in Asc−/− and Asc shRNA transfected mice on the HFD was accompanied by attenuated proteinuria, albuminuria, foot process effacement of podocytes and loss of podocyte slit diaphragm molecules. In conclusion, activation and formation of inflammasomes in podocytes are importantly implicated in the development of obesity-associated glomerular injury. 相似文献
47.
Lab-scale study of an anaerobic membrane bioreactor (AnMBR) for dilute municipal wastewater treatment 总被引:1,自引:0,他引:1
Seung Hyuk Baek Krishna R. Pagilla Hyung-Jin Kim 《Biotechnology and Bioprocess Engineering》2010,15(4):704-708
Anaerobic bioreactors supplemented with membrane technology have become quite popular, owing to their favorable energy recovery characteristics. In this study, a lab-scale anaerobic Membrane Bioreactor (AnMBR) was assessed in experimental treatments of pre-settled dilute municipal wastewater obtained from a full-scaled wastewater treatment plant. The MBR system was operated in continuous flow mode for 440 days. To evaluate the performance of the AnMBR under various loading rates, the hydraulic retention time (HRT) was reduced in a stepwise manner (from 2 to 0.5 days). Afterward, the mixed liquor suspended solids (MLSS) were reduced from 7,000 to 3,000 mg/L in increments of 1,000 mg/L, resulting in a decrease in solids retention time (SRT) at a constant HRT of 1.0 day. The soluble chemical oxygen demand (SCOD) concentration in the feed varied between 38 and 131 mg/L, whereas the average permeate SCOD ranged between 18 and 37 mg/L, reflecting excellent effluent quality. The AnMBR performance in terms of COD removal proved stable, despite variations in influent characteristics and HRT and SRT changes. The concentration of extracellular polymeric substance (EPS) was reduced with decreases in HRT from 42 to 22 mg VS/mg of MLSS, thereby indicating that the increased biomass concentration biodegraded the EPS at lower HRTs. AnMBR is, therefore, demonstrably a feasible option for the treatment of dilute wastewater with separate stage nitrogen and phosphorus removal processes. 相似文献
48.
Om Prakash Shakti Mehrotra Aneesh Krishna Bhartendu N. Mishra 《Journal of theoretical biology》2010,265(4):579-585
The present study deals with ANN based prediction of culture parameters in terms of inoculum density, pH and volume of growth medium per culture vessel and sucrose content of the growth medium for Glycyrrhiza hairy root cultures. This kind of study could be a model system in exploitation of hairy root cultures for commercial production of pharmaceutical compounds using large bioreactors. The study is aimed to evaluate the efficiency of regression neural network and back propagation neural network for the prediction of optimal culture conditions for maximum hairy root biomass yield. The training data for regression and back propagation networks were primed on the basis of function approximation, where final biomass fresh weight (fwt) was considered as a function of culture parameters. On this basis the variables in culture conditions were described in the form of equations which are for inoculum density: y=0.02x+0.04, for pH of growth medium: y=x+2.8, for sucrose content in medium: y=9.9464x+(−9.7143) and for culture medium per culture vessel: y=10x. The fresh weight values obtained from training data were considered as target values and further compared with predicted fresh weight values. The empirical data were used as testing data and further compared with values predicted from trained networks. Standard MATLAB inbuilt generalized regression network with radial basis function radbas as transfer function in layer one and purelin in layer two and back propagation having purelin as transfer function in output layer and logsig in hidden layer were used. Although in comparative assessment both the networks were found efficient for prediction of optimal culture conditions for high biomass production, more accuracy in results was seen with regression network. 相似文献
49.
Rajeev K. Singh Kuldeep K. Lal Vindhya Mohindra Peyush Punia Rama S. Sah Akhilesh K. Mishra Rajesh Kumar B. N. Mishra W. S. Lakra 《Biochemical genetics》2010,48(9-10):760-778
The population structure of Labeo calbasu from 11 rivers belonging to the Indus, Ganges, Bhima, Mahanadi, and Godavari basins was investigated using allozyme marker systems. Seven out of 20 allozyme loci (35%) were polymorphic (P < 0.99). Both probability and score tests indicated significant deviation of genotype proportions from Hardy–Weinberg expectations at two loci, XDH* (Mahanadi, Bhima, and Godavari) and G6PDH* (Mahanadi). A pairwise genetic homogeneity test and F ST values indicated a low-to-moderate level (0.0515) of genetic structuring in the wild population of L. calbasu. AMOVA analysis also indicated moderate differentiation among the samples from different river basins. Analysis for genetic bottleneck was performed under the infinite allele model. The study revealed nine genetic stocks of L. calbasu from the natural population across Indian rivers. Evidence of genetic bottlenecks in some rivers was also revealed. 相似文献
50.
The Hem/Kette/Nap1 protein is involved in many biological processes. We have recently reported that Hem is required for the normal migration of neurons in the Drosophila embryo. In this paper, we report that Hem regulates the asymmetric division of neural precursor cells. We find that a well-studied Hem/Kette mutant allele produces at least two main, but possibly more, phenotypic classes of mutant embryos, and these phenotypes correlate with variable levels of maternal wild type Hem protein in the developing embryo. While the weaker class exhibits weak axon guidance defect and the mis-migration of neurons, the stronger class causes severe axon guidance defects, mis-migration of neurons and symmetric division of ganglion mother cells (GMC) of the RP2/sib lineage. We also show that the basis for the loss of asymmetric division is due to non-localization of Inscuteable and Numb in GMC-1. A non-asymmetric Numb segregates to both daughter cells of GMC-1, which then prevents Notch signaling from specifying a sib fate. This causes both cells to adopt an RP2 fate. Furthermore, loss of function for Abelson tyrosine kinase also causes loss of asymmetric localization of Inscuteable and Numb and symmetric division of GMC-1, the loss of function for WAVE has a very weakly penetrant loss of asymmetry defect. These results define another role for Hem/Kette/Nap1 in a neural precursor cell during neurogenesis. 相似文献