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951.
Pardeep Kumar Bhardwaj Paramvir Singh Ahuja Sanjay Kumar 《Molecular biology reports》2010,37(2):1003-1010
Caragana [Caragana jubata (Pall.) Poir] is a temperate plant that thrives well under extremes of cold in high altitude of Himalaya and hence the plant
is expected to be a source of genes that might play an important role in tolerance to low temperature (LT). In order to identify
LT inducible gene(s), differential display of mRNA (DD) was performed using the apical buds growing under snow as well as
growing in the near vicinity without snow, and a LT inducible QM gene (CjQM) homologue was identified. Realizing the importance of QM gene (which encodes human Wilms’ tumor suppressor QM protein) in aggregation of 40 and 60S ribosomal subunit and that not
much has been reported on this gene in plant systems in relation to its relationship with LT, full length cDNA of CjQM was cloned through rapid amplification of cDNA ends. The gene (977 bp), encoded by small gene family, had an open reading
frame of 651 bp and was found to be intronless. The gene exhibited up-regulation within 20 min of exposure to LT and abscisic
acid (ABA), but no significant change in gene expression was observed in response to drought stress (DS), salicylic acid (SA)
and methyl jasmonate (MJ) application. Up-regulation of CjQM was obtained in the tissues growing in situ under snow. Non-responsiveness of CjQM towards DS, SA and MJ, but up-regulation in response to LT and ABA suggested a specific regulation of the gene in Caragana
under varied cues. 相似文献
952.
The anti-cancer activity and cytotoxicity of imidazolium-based ionic liquids has been determined for the first time via NCI’s in vitro 60 human tumor cell lines. The preliminary SAR showed that the chain length of alkyl substitution at N-3 position of imidazole ring plays crucial role towards anti-tumor activity and cytotoxicity of these ionic liquids. The ionic liquids with alkyl substitution of C-12 chain length were found to be effective against all 60 tumor cell lines and show very low cytotoxicity in most of the cases. Further increase in chain length resulted in enhanced growth inhibition of tumor cell lines as well as high cytotoxicity. Interestingly, active compounds 1-dodecyl-3-methylimidazolium chloride (8), 1-dodecyl-3-methylimidazolium tetrafluoroborate (9), 1-hexadecyl-3-methylimidazoium chloride (10), 1-octadecyl-3-methylimidazolium chloride (11), 1-octadecyl-3-methylimidazolium hexafluorophosphate (12), 1-octadecyl-3-methylimidazolium bis(triflic)imide (13) and 1-octadecyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate (14) were highly active against leukemia cell lines, especially compounds 13 and 14 where the cytotoxicity was also very low as given by LC50 >100 μM in all six leukemia cell lines. 相似文献
953.
954.
Derek C. Martyn Amarjit Nijjar Cassandra A. Celatka Ralph Mazitschek Joseph F. Cortese Erin Tyndall Hanlan Liu Maria M. Fitzgerald Thomas J. O’Shea Sanjay Danthi Jon Clardy 《Bioorganic & medicinal chemistry letters》2010,20(1):228-231
Two sets of diaminopyrimidines, totalling 45 compounds, were synthesized and assayed against Plasmodium falciparum. The SAR was relatively shallow, with only the presence of a 2-(pyrrolidin-1-yl)ethyl group at R2 significantly affecting activity. A subsequent series addressed high Log D values by introducing more polar side groups, with the most active compounds possessing diazepine and N-benzyl-4-aminopiperidyl groups at R1/R2. A final series attempted to address high in vitro microsomal clearance by replacing the C6-Me group with CF3, however antiplasmodial activity decreased without any improvement in clearance. The C6-CF3 group decreased hERG inhibition, probably as a result of decreased amine basicity at C2/C4. 相似文献
955.
Harmeet S. Sandhu Sameer Sapra Mukesh Gupta Kunal Nepali Raju Gautam Sunil Yadav Raj Kumar Sanjay M. Jachak Manoj Chugh Manish K. Gupta Om P. Suri K.L. Dhar 《Bioorganic & medicinal chemistry》2010,18(15):5626-5633
A series of arylidene analogues of Meldrum’s acid were synthesized and evaluated for in vitro antimalarial and antioxidant activities for the first time. The influence of various physico-chemical parameters such as dielectric constant (ε), donor number (DN), acceptor number (AN), hydrogen bond donor (HBD), hydrogen bond acceptor (HBA), and solubilizing power of the solvents on Meldrum’s acid anion generation and thus on promoting the Knoevenagel condensation of Meldrum’s acid with aryl aldehydes has been discussed. Five compounds 9l, 9m, 9n, 9r, and 9s were found to be most active against Plasmodium falciparum with IC50 values in the range of 9.68–16.11 μM. Compound 9l exhibited the most potent antimalarial activity (IC50 9.68 μM). The compounds were also found to possess antioxidant activity when tested against DPPH and ABTS free radicals. 相似文献
956.
In the recent past, there has been a resurgence of interest in Chikungunya virus (CHIKV) attributed to massive outbreaks of Chikungunya fever in the South-East Asia Region. This has reflected in substantial increase in submission of CHIKV genome sequences to NCBI (National Center for Biotechnology Information) database. Hereby we submit a database "CHIKVPRO" containing structural and functional annotation of Chikungunya virus proteins (25 strains) submitted in the NCBI repository. The CHIKV genome encodes for 9 proteins:4 non-structural and 5 structural. The CHIKVPRO database aims to provide the virology community with a single accession authoritative resource for CHIKV proteome- with reference to physiochemical and molecular properties, proteolytic cleavage sites, hydrophobicity, transmembrane prediction, and classification into functional families using SVMProt and other Expasy tools. AVAILABILITY: The database is freely available at http://www.chikvpro.info/ 相似文献
957.
Simranjeet Singh Vijay Kumar Dhriti Kapoor Sanjay Kumar Satyender Singh Daljeet Singh Dhanjal Shivika Datta Jastin Samuel Pinaki Dey Shanquan Wang Ram Prasad Joginder Singh 《Physiologia plantarum》2020,168(2):301-317
In the recent times, plants are facing certain types of environmental stresses, which give rise to formation of reactive oxygen species (ROS) such as hydroxyl radicals, hydrogen peroxides, superoxide anions and so on. These are required by the plants at low concentrations for signal transduction and at high concentrations, they repress plant root growth. Apart from the ROS activities, hydrogen sulfide (H2S) and nitric oxide (NO) have major contributions in regulating growth and developmental processes in plants, as they also play key roles as signaling molecules and act as chief plant immune defense mechanisms against various biotic as well as abiotic stresses. H2S and NO are the two pivotal gaseous messengers involved in growth, germination and improved tolerance in plants under stressed and non-stress conditions. H2S and NO mediate cell signaling in plants as a response to several abiotic stresses like temperature, heavy metal exposure, water and salinity. They alter gene expression levels to induce the synthesis of antioxidant enzymes, osmolytes and also trigger their interactions with each other. However, research has been limited to only cross adaptations and signal transductions. Understanding the change and mechanism of H2S and NO mediated cell signaling will broaden our knowledge on the various biochemical changes that occur in plant cells related to different stresses. A clear understanding of these molecules in various environmental stresses would help to confer biotechnological applications to protect plants against abiotic stresses and to improve crop productivity. 相似文献
958.
Sanjay Basak Vilasagaram Srinivas Aswani Mallepogu Asim K. Duttaroy 《Cell biology international》2020,44(5):1237-1251
Curcumin has a protective role in placental diseases like preeclampsia and preterm birth. Very little is known about its functional effects on growth, angiogenesis, and epigenetic activities of human first trimester placenta. HTR8/SVneo trophoblasts cells were used as model for human first trimester placenta. Effects of curcumin (≥80%) in these cells were investigated using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), radioactive thymidine uptake, quantitative real‐time polymerase chain reaction (qRT‐PCR), promoter DNA methylation, qRT‐PCR array, tube formation, wound healing, and immunoblot assays. PC3 (prostate cancer), JEG‐3 (trophoblast), and HMEC‐1 (endothelial) cells were used as control in various experiments. Unlike in PC3 cells, curcumin stimulated growth, proliferation, and viability in HTR8/SVneo cells. Curcumin increased tube formation, and messenger RNA (mRNA) expression of angiogenic factors such as vascular endothelial growth factor A (VEGFA) and protein expression of proangiogenic factor VEGF receptor‐2 and fatty acid‐binding protein‐4 (FABP4) in these cells. Curcumin‐stimulated tube formation was associated with an increased expression of VEGFR2 and FABP4. The stimulatory effects of curcumin were inhibited by VEGFR2 (SU5416) and FABP4 (BMS309403) inhibitors. Curcumin also significantly increased both mRNA and protein expression of HLA‐G in HTR8/SVneo cells. Curcumin increased mRNA expression of DNMT3A and NOTCH signaling system whereas down‐regulated mRNA expression of HSD11β2. Curcumin enhanced hypomethylation of gene promoters against oxidative stress and DNA damage pathway mediators. Curcumin promotes cell growth, migration, and thus angiogenic potential of these cells. Increased expression of HLA‐G by curcumin, hitherto unknown, is a novel finding since HLA‐G not only favors the immune environment for invasive trophoblasts but also positively modulates angiogenesis. 相似文献
959.
Rashmi Venkatasubbaiah Prabhushankar Hema Bommanamane Sanjay Konasur Rajesh 《Plant Cell, Tissue and Organ Culture》2021,146(3):515-529
Plant Cell, Tissue and Organ Culture (PCTOC) - This study proposes the tenacious vitality for biomass production and eco-friendly, cost-effective, renewable silver nanoparticles (AgNPs)... 相似文献
960.