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1.
Vikas Yadav Patade Sujata Bhargava Penna Suprasanna 《Plant Cell, Tissue and Organ Culture》2012,108(2):279-286
In order to discriminate between the ionic and osmotic components of salt stress, sugarcane (Saccharum officinarum L. cv. Co 86032) calli were cultured on media containing NaCl or polyethylene glycol (PEG) 8000 that exerted the same osmotic
pressure (−0.7 MPa). PEG stress exposure for 15 days led to significant growth reduction and loss in water content than salt
stressed and control tissues. Osmotic adjustment (OA) was observed in callus tissues grown on salt, but was not evident in
callus grown on PEG. Oxidative damage to membranes, estimated in terms of accumulation of thiobarbituric acid reactive substances-TBARS
and electrolytic leakage was significantly higher in both the stressed calli than the control however, the extent of damage
was more in the PEG stressed calli. The stressed callus tissues showed inhibition of ascorbate peroxidase activity, while
catalase activity was increased. These results indicate sensitivity of cells to PEG-mediated stress than salt stress and differences
in their OA to these two stress conditions. The sensitivity to the osmotic stress indicate that expression of the stress tolerance
response requires the coordinated action of different tissues in a plant and hence was not expressed at the cellular level. 相似文献
2.
Rashi Verma Monika Yadav Rajabrata Bhuyan Shweta Aggarwal Arnab Nayek 《Journal of receptor and signal transduction research》2016,36(6):601-616
Computer-aided antibody engineering has been successful in the design of new biologics for disease diagnosis and therapeutic interventions. Interleukin-6 (IL-6), a well-recognized drug target for various autoimmune and inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, and psoriasis, was investigated in silico to design potential lead antibodies. Here, crystal structure of IL-6 along with monoclonal antibody olokizumab was explored to predict antigen–antibody (Ag???Ab)-interacting residues using DiscoTope, Paratome, and PyMOL. Tyr56, Tyr103 in heavy chain and Gly30, Ile31 in light chain of olokizumab were mutated with residues Ser, Thr, Tyr, Trp, and Phe. A set of 899 mutant macromolecules were designed, and binding affinity of these macromolecules to IL-6 was evaluated through Ag???Ab docking (ZDOCK, ClusPro, and Rosetta server), binding free-energy calculations using Molecular Mechanics/Poisson Boltzman Surface Area (MM/PBSA) method, and interaction energy estimation. In comparison to olokizumab, eight newly designed theoretical antibodies demonstrated better result in all assessments. Therefore, these newly designed macromolecules were proposed as potential lead antibodies to serve as a therapeutics option for IL-6-mediated diseases. 相似文献
3.
For estimation of growth, the efficiency of linked cross sectional scheme has been compared with pure longitudinal and cross sectional schemes. The relevant estimation theory has been developed and the expressions for the optimum estimators alongwith their variances have been derived. It has been observed that for estimation of growth, the linked cross-sectional scheme has been observed to be less efficient as compared to pure longitudinal scheme but more efficient than pure cross-sectional scheme. 相似文献
4.
5.
R. R. Yadav 《Journal of biosciences》2009,34(5):699-707
Tree-ring analyses from semi-arid to arid regions in western Himalaya show immense potential for developing millennia long
climate records. Millennium and longer ring-width chronologies of Himalayan pencil juniper (Juniperus polycarpos), Himalayan pencil cedar (Cedrus deodara) and Chilgoza pine (Pinus gerardiana) have been developed from different sites in western Himalaya. Studies conducted so far on various conifer species indicate
strong precipitation signatures in ring-width measurement series. The paucity of weather records from stations close to tree-ring
sampling sites poses difficulty in calibrating tree-ring data against climate data especially precipitation for its strong
spatial variability in mountain regions. However, for the existence of strong coherence in temperature, even in data from
distant stations, more robust temperature reconstructions representing regional and hemispheric signatures have been developed.
Tree-ring records from the region indicate multi-century warm and cool anomalies consistent with the Medieval Warm Period
and Little Ice Age anomalies.
Significant relationships noted between mean premonsoon temperature over the western Himalaya and ENSO features endorse utility
of climate records from western Himalayan region in understanding long-term climate variability and attribution of anthropogenic
impact. 相似文献
6.
7.
Non-pathogenic, environmental strain ofVibrio cholerae, ELTOR Ogawa EW6 carries a copy of the cholera toxin gene in its chromosome. Restriction enzyme digestion followed by Southern
blot analysis revealed that the structure of the cholera toxin gene in this organism is different from that found in the virulent
strains. The xbaI site which has been found to be conserved in the cholera toxin of the virulent strains examined so far,
is absent here. Results of the RNA dot blot analysis indicated that the cholera toxin gene in EW6 is transcribed much less
efficiently compared to the cholera toxin gene present in the virulent strainVibrio cholerae classical Inaba 569B. 相似文献
8.
Paul J. Chuba Myron A. Leon Amit Banerjee Sunil Palchaudhuri 《Molecular & general genetics : MGG》1989,216(2-3):287-292
Summary
Escherichia coli K12 cells carrying a cloned 1.4 kb HindIII fragment from plasmid ColV2-K94, showed increased survival in guinea pig serum. The recombinant plasmid also conferred group II surface exclusion, i.e. the cells were reduced in recipient ability towards the incoming plasmid R538drd in conjugation experiments. Southern blotting suggested homology with bacteriophage lambda DNA and to the insertion element IS2. Determination of the DNA sequence of the fragment demonstrated the presence of a truncated IS2 (165 bp), separated by 250 bp from a 900 bp stretch of homology with lambda DNA, beginning within the Rz gene and continuing in the rightward direction on the lambda map. A 97 amino acid open reading frame (ORF) adjacent to Rz and on the opposite strand, remained intact in iss, with several amino acid changes. The ORF in iss is preceded by sequences resembling prokaryotic ribosome binding sites and promoters. 相似文献
9.
V. Johnson M. Singh V. S. Saini V. R. Sista N. K. Yadav 《World journal of microbiology & biotechnology》1992,8(4):382-384
Maximum lipid production (66% w/w dry wt) inRhodotorula glutinis IIP-30 utilizing glucose in a fed-batch fermentation under N-limiting conditions at 30°C, was at pH 4. At pH 3, 5 and 6, the lipid contents were 12%, 48% and 44%, respectively. There was only a small change in the fatty acid profile over the pH range examined, although the ergosterol content decreased by a third as the pH increased. 相似文献
10.