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961.
N. V. Suresh Kumar 《Journal of molecular modeling》2016,22(6):141
Using B3LYP and B97D functionals of density functional theory (DFT), homochiral and heterochiral cyclic trimerization of imidazole based heterocyclic amino acids are studied in gas phase and solvent phase, i. e., Acetonitrile. Both the functionals show that formation of homochiral cyclic tripeptide is thermodynamically and kinetically favorable over its heterochiral counterpart in gas phase. The functional, B97D, decreases the height of reaction barriers significantly compared to those predicted by the functional B3LYP. The reaction pathways explored using PCM implicit solvent model show reduced kinetic favorability for formation of the homochiral cyclic tripeptide over its heterochiral counterpart. The results are substantiated by structural aspects. 相似文献
962.
Somesh Mishra Suresh Gupta Smita Raghuvanshi Pratibha Pal 《Bioprocess and biosystems engineering》2016,39(8):1247-1258
The ongoing work on global warming resulting from green house gases (GHGs) has led to explore the possibility of bacterial strains which can fix carbon dioxide (CO2) and can generate value-added products. The present work is an effort in this direction and has carried out an exhaustive batch experiments for the fixation of CO2 using B. Cereus SM1 isolated from sewage treatment plant (STP). The work has incorporated 5-day batch run for gaseous phase inlet CO2 concentration of 13 ± 1 % (%v/v). 84.6 (±5.76) % of CO2 removal was obtained in the gaseous phase at mentioned CO2 concentration (%v/v). Energetic requirement for CO2 fixation was assessed by varying Fe[II] ion concentration (0–200 ppm) on the per-day basis. The cell lysate obtained from CO2 fixation studies (Fe[II] ion = 100 ppm) was analyzed using Fourier transformation infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC–MS). This analysis confirmed the presence of fatty acids and hydrocarbon as valuable products. The hydrocarbons were found in the range of C11–C22 which is equivalent to light oil. The obtained fatty acids were found in the range of C11–C19. The possibility of fatty acid conversion to biodiesel was explored by carrying out the transesterification reaction. The yield of biodiesel was obtained as 86.5 (±0.048) % under the transesterification reaction conditions. Results of this research work can provide the valuable information in the implementation of biomitigation of CO2 at real scenario. 相似文献
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Nevena Jeremic Gregory J. Weber Nicholas T. Theilen Suresh C. Tyagi 《Journal of cellular physiology》2020,235(6):5229-5240
Human studies have shown high-intensity interval training (HIIT) has beneficial cardiovascular effects and is typically more time-efficient compared with traditional endurance exercise. The main goal of this study is to show the potential molecular and functional cardiovascular benefits of HIIT compared with endurance training (ET). Three groups of mice were used including sedentary-control, ET mice, and HIIT mice groups. Results indicated ejection fraction was increased in HIIT compared with ET while fractional shortening was increased in the HIIT group compared with both groups. Blood flow of the abdominal aorta was increased in both exercise groups compared with control. Increases in cross-sectional area and mitochondrial and antioxidative markers in HIIT compared with control were observed, along with several microRNAs. These findings indicate HIIT has specific cardiac-protective effects and may be a viable alternative to traditional ET as a cardiovascular preventative medicine intervention. 相似文献
967.
Soma Shiva Nageswara Rao Singireesu Sunil Misra Sujan Kumar Mondal Suresh Yerramsetty Nivedita Sahu Suresh Babu K 《Cell biology and toxicology》2018,34(2):125-142
Costunolide (CE) is a sesquiterpene lactone well-known for its antihepatotoxic, antiulcer, and anticancer activities. The present study focused on the evaluation of the cytogenetic toxicity and cellular death-inducing potential of CE in CHO cells, an epithelial cell line derived from normal ovary cells of Chinese hamster. The cytotoxic effect denoting MTT assay has shown an IC50 value of 7.56 μM CE, where 50% proliferation inhibition occurs. The oxidative stress caused by CE was confirmed based on GSH depletion induced cell death, conspicuously absent in N-acetylcysteine (GSH precursor) pretreated cells. The evaluation of genotoxic effects of CE using cytokinesis block micronucleus assay and chromosomal aberration test has shown prominent induction of binucleated micronucleated cells and aberrant metaphases bearing chromatid and chromosomal breaks, indicating CE’s clastogenic and aneugenic potential. The apoptotic death in CE treated cells was confirmed by an increase in the number of cells in subG1 phase, exhibiting chromatin condensation and membranous phosphatidylserine translocation. The apoptosis induction follows mitochondrial mediation, evident from an increase in the BAX/Bcl-2 ratio, caspase-3/7 activity, and mitochondrial membrane permeability. CE also induces cytostasis in addition to apoptosis, substantiated by the reduced cytokinetic (replicative indices) and mitotic (mitotic indices and histone H3 Ser-10 phosphorylation) activities. Overall, the cellular GSH depletion and potential genotoxic effects by CE led the CHO cells to commit apoptosis and lowered cell division. The observed sensitivity of CHO cells doubts unintended adverse effects of CE on normal healthy cells, suggesting higher essentiality of further studies in order to establish its safety efficacy in therapeutic explorations. 相似文献
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Raj Kishore Suresh K. Verma Alexander R. Mackie Erin E. Vaughan Tatiana V. Abramova Ito Aiko Prasanna Krishnamurthy 《PloS one》2013,8(4)
Diabetes is associated with a higher incidence of myocardial infarction (MI) and increased risk for adverse vascular and fibrogenic events post-MI. Bone marrow-derived progenitor cell (BMPC) therapy has been shown to promote neovascularization, decrease infarct area and attenuate left ventricular (LV) dysfunction after MI. Unlike vascular effects, the anti-fibrosis mechanisms of BMPC, specifically under diabetic conditions, are poorly understood. We demonstrated that intramyocardial delivery of BMPCs in infarcted diabetic db/db mice significantly down-regulates profibrotic miRNA-155 in the myocardium and improves LV remodeling and function. Furthermore, inhibition of paracrine factor hepatocyte growth factor (HGF) signaling in vivo suppressed the BMPC-mediated inhibition of miR-155 expression and the associated protective effect on cardiac fibrosis and function. In vitro studies confirmed that the conditioned media of BMPC inhibited miR-155 expression and profibrotic signaling in mouse cardiac fibroblasts under diabetic conditions. However, neutralizing antibodies directed against HGF blocked these effects. Furthermore, miR-155 over-expression in mouse cardiac fibroblasts inhibited antifibrotic Sloan-Kettering Institute proto-oncogene (Ski) and Ski-related novel gene, non-Alu-containing (SnoN) signaling and abrogated antifibrogenic response of HGF. Together, our data demonstrates that paracrine regulation of cardiac miRNAs by transplanted BMPCs contributes to the antifibrotic effects of BMPC therapy. BMPCs release HGF, which inhibits miR-155-mediated profibrosis signaling, thereby preventing cardiac fibrosis. These data suggest that targeting miR-155 might serve as a potential therapy against cardiac fibrosis in the diabetic heart. 相似文献
970.
Eduardo Ekman Schenberg Jo?o Felipe Morel Alexandre Renato Filev Andre Mascioli Cravo Jo?o Ricardo Sato Suresh D. Muthukumaraswamy Maurício Yonamine Marian Waguespack Izabela Lomnicka Steven A. Barker Dartiu Xavier da Silveira 《PloS one》2015,10(9)
Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca''s compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8–13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30–50 and 50–100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca’s chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it''s potential therapeutic effects is offered. 相似文献