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781.
Showket Hussain Ankita Singh Sheeraz Un Nazir Sonam Tulsyan Asiya Khan Ramesh Kumar Nasreena Bashir Pranay Tanwar Ravi Mehrotra 《Journal of cellular biochemistry》2019,120(9):14213-14225
Cancer is a disease that claims millions of lives each year across the world. Despite advancement in technologies and therapeutics for treating the disease, these modes are often found to turn ineffective during the course of treatment. The resistance against drugs in cancer patients stems from multiple factors, which constitute genetic heterogeneity like gene mutations, tumor microenvironment, exosomes, miRNAs, high rate of drug efflux from cells, and so on. This review attempts to collate all such known and reported factors that influence cancer drug resistance and may help researchers with information that might be useful in developing better therapeutics in near future to enable better management of several cancers across the world. 相似文献
782.
Prabhakar Singh Riyazat Khadim Ankit K. Singh Urmilesh Singh Priyanka Maurya Anupam Tiwari Ravi K. Asthana 《Journal of phycology》2019,55(1):60-73
The objective of the present study was to characterize intrinsic physiological and biochemical properties of the wall‐less unicellular cholorophyte Dunaliella salina isolated from a hypersaline Sambhar Lake. The strain grew optimally at 0.5 M NaCl and 16:8 h L:D photoperiod along with maintaining low level of intracellular Na+ even at higher salinity, emphasizing special features of its cell membranes. It was observed that the cells experienced stress beyond 2 M NaCl as evidenced by increased intracellular reactive oxygen species and antioxidative enzymes, nevertheless proline and malondialdehyde content declined sharply accompanied by higher neutral lipid accumulation. Salinity exceeding 2 M resulted decrease in photosynthetic quantum yield (Fv/Fm) and enhanced glycerol synthesis accompanied by leakage. Super oxide dismutase seemed to play a pivotal role in antioxidative defense as eight isoforms were expressed differentially while catalase and glutathione peroxidase showing no significant change in their expression at higher salinity. The ability of D. salina to grow in range of salinities by sustaining healthy photosynthetic apparatus along with accumulation of valuable products made this alga an ideal organism that can be exploited as resource for biofuel and commercial products. 相似文献
783.
Navaneetha Nambagari Shyam Perka Ravi Kumar Vuradi 《Nucleosides, nucleotides & nucleic acids》2019,38(6):400-417
Three new cobalt(III) polypyridyl complexes, [Co(L - L)2IIP]3+ where IIP = 2-(2H-isoindol-1-yl)-2H-imidazo[4,5-f][1, 10]phenanthroline, L?=?1) phen (1,10-phenanthroline), 2) bpy (2,2’bipyridyl), 3) dmb (4, 4-dimethyl 2, 2’-bipyridine) have been synthesized, characterized (UV –VIS, IR, 1HNMR and 13C NMR spectroscopy) and screened for their in vitro antibacterial activity against E.coli, Staphylococcus aureus and Bacillus subtilis. The binding of these complexes with calf-thymus DNA (CT-DNA) has been investigated by absorption and fluorescence spectroscopy, viscosity measurements. The experimental studies indicate that complexes bind to CT-DNA by means of intercalation, but with different binding affinities due to differences in the planarity of the ancillary ligand. The complexes promote photocleavage of plasmid DNA from super coiled form I to the open circular form II. The antibacterial activities suggest that the metal complexes are more active as compared to the prepared un-complexed IIP ligand.In addition, a conformational search was carried out by Molecular Dynamics Simulations, and docking revealed that complexes intercalate between base pairs of DNA. The experimental and computational approaches reveal that the length of the intercalator and the nature of ancillary ligand are highly important factors for DNA binding. 相似文献
784.
Naser Poursarebani Tina Seidensticker Ravi Koppolu Corinna Trautewig Piotr Gawroński Federica Bini Geetha Govind Twan Rutten Shun Sakuma Akemi Tagiri Gizaw M. Wolde Helmy M. Youssef Abdulhamit Battal Stefano Ciannamea Tiziana Fusca Thomas Nussbaumer Carlo Pozzi Andreas B?rner Udda Lundqvist Takao Komatsuda Silvio Salvi Roberto Tuberosa Cristobal Uauy Nese Sreenivasulu Laura Rossini Thorsten Schnurbusch 《Genetics》2015,201(1):155-165
785.
Archna Ravi Shelly Kaushik Aarthi Ravichandran Catherine Qiurong Pan Boon Chuan Low 《The Journal of biological chemistry》2015,290(7):4149-4162
Deleted in Liver Cancer 1 (DLC1) is a RHO GTPase-activating protein (GAP) that negatively regulates RHO. Through its GAP activity, it modulates the actin cytoskeleton network and focal adhesion dynamics, ultimately leading to suppression of cell invasion and metastasis. Despite its presence in various structural and signaling components, little is known about how the activity of DLC1 is regulated at focal adhesions. Here we show that EGF stimulation activates the GAP activity of DLC1 through a concerted mechanism involving DLC1 phosphorylation by MEK/ERK and its subsequent dephosphorylation by protein phosphatase 2A (PP2A) and inhibition of focal adhesion kinase by MEK/ERK to allow the binding between DLC1 and PP2A. Phosphoproteomics and mutation studies revealed that threonine 301 and serine 308 on DLC1, known previously to be mutated in certain cancers, are required for DLC1-PP2A interaction and the subsequent activation of DLC1 upon their dephosphorylation. The intricate interplay of this “MEK/ERK-focal adhesion kinase-DLC1-PP2A” quartet provides a novel checkpoint in the spatiotemporal control of cell spreading and cell motility. 相似文献
786.
787.
Yogananda S. Markandeya Laura J. Phelan Marites T. Woon Alexis M. Keefe Courtney R. Reynolds Benjamin K. August Timothy A. Hacker David M. Roth Hemal H. Patel Ravi C. Balijepalli 《The Journal of biological chemistry》2015,290(36):22085-22100
Pathological cardiac hypertrophy is characterized by subcellular remodeling of the ventricular myocyte with a reduction in the scaffolding protein caveolin-3 (Cav-3), altered Ca2+ cycling, increased protein kinase C expression, and hyperactivation of calcineurin/nuclear factor of activated T cell (NFAT) signaling. However, the precise role of Cav-3 in the regulation of local Ca2+ signaling in pathological cardiac hypertrophy is unclear. We used cardiac-specific Cav-3-overexpressing mice and in vivo and in vitro cardiac hypertrophy models to determine the essential requirement for Cav-3 expression in protection against pharmacologically and pressure overload-induced cardiac hypertrophy. Transverse aortic constriction and angiotensin-II (Ang-II) infusion in wild type (WT) mice resulted in cardiac hypertrophy characterized by significant reduction in fractional shortening, ejection fraction, and a reduced expression of Cav-3. In addition, association of PKCα and angiotensin-II receptor, type 1, with Cav-3 was disrupted in the hypertrophic ventricular myocytes. Whole cell patch clamp analysis demonstrated increased expression of T-type Ca2+ current (ICa, T) in hypertrophic ventricular myocytes. In contrast, the Cav-3-overexpressing mice demonstrated protection from transverse aortic constriction or Ang-II-induced pathological hypertrophy with inhibition of ICa, T and intact Cav-3-associated macromolecular signaling complexes. siRNA-mediated knockdown of Cav-3 in the neonatal cardiomyocytes resulted in enhanced Ang-II stimulation of ICa, T mediated by PKCα, which caused nuclear translocation of NFAT. Overexpression of Cav-3 in neonatal myocytes prevented a PKCα-mediated increase in ICa, T and nuclear translocation of NFAT. In conclusion, we show that stable Cav-3 expression is essential for protecting the signaling mechanisms in pharmacologically and pressure overload-induced cardiac hypertrophy. 相似文献
788.
789.
Lucia Gutiérrez Silvia Germán Silvia Pereyra Patrick M. Hayes Carlos A. Pérez Flavio Capettini Andres Locatelli Natalia M. Berberian Esteban E. Falconi Rigoberto Estrada Dario Fros Victor Gonza Hernan Altamirano Julio Huerta-Espino Edgar Neyra Gisella Orjeda Sergio Sandoval-Islas Ravi Singh Kelly Turkington Ariel J. Castro 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2015,128(3):501-516