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961.
Shafaqat Ali Muhammad Rizwan Najeeb Ullah Saima Aslam Bharwana Muhammad Waseem Muhammad Ahsan Farooq Ghulam Hasan Abbasi Mujahid Farid 《Acta Physiologiae Plantarum》2016,38(11):262
Accumulation of excess copper (Cu) in agricultural soils can decrease growth and quality of crops grown on these soils and a little information is available on the role of silicon (Si) in reducing Cu toxicity in plants. A hydroponic study was conducted to investigate the effects of Si (1.0 mM) on growth and physiology of cotton seedlings grown on different Cu (0, 25, and 50 µM) concentrations. Elevated levels of Cu decreased growth, biomass, photosynthetic pigments, and gas exchange characteristics, and increased the electrolyte leakage (EL), hydrogen peroxide (H2O2), and thiobarbituric acid reactive substances (TBARS) contents in leaf, stem, and roots of cotton seedlings. Cu stress alone decreased the activities of key antioxidant enzymes in cotton seedlings. Exogenous application of Si alleviated the toxic effects of Cu on cotton seedlings by improving growth, photosynthetic pigments, and gas exchange characteristics under Cu stress. The Si application decreased Cu concentrations in leaves, stem, and roots as compared with the control plants. Furthermore, Si decreased oxidative stress as evidenced by decreased EL, H2O2, and TBARS contents, and increased the antioxidant enzyme activities in cotton seedlings. This study provides evidences of Si-mediated reduction of Cu toxicity in cotton seedlings at physiological and biochemical levels. 相似文献
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963.
Anning Li Yue Wu Jenny Linnoila Benjamin Pulli Cuihua Wang Matthias Zeller Muhammad Ali Grant K. Lewandrowski Jinghui Li Benoit Tricot Edmund Keliher Gregory R. Wojtkiewicz Giulia Fulci Xiaoyuan Feng Bakhos A. Tannous Zhenwei Yao John W. Chen 《Cancer immunology, immunotherapy : CII》2016,65(12):1545-1554
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Total synthesis,structural, and biological evaluation of stylissatin A and related analogs 下载免费PDF全文
Farzana Shaheen Almas Jabeen Samreen Ashraf Muhammad Nadeem‐ul‐Haque Zafar Ali Shah Muhammad Asad Ziaee Nida Dastagir A. Ganesan 《Journal of peptide science》2016,22(9):607-617
The natural product cyclic peptide stylissatin A ( 1a ) was reported to inhibit nitric oxide production in LPS‐stimulated murine macrophage RAW 264.7 cells. In the current study, solid‐phase total synthesis of stylissatin A was performed by using a safety‐catch linker and yielded the peptide with a trans‐Phe7‐Pro6 linkage, whereas the natural product is the cis rotamer at this position as evidenced by a marked difference in NMR chemical shifts. In order to preclude the possibility of 1b being an epimer of the natural product, we repeated the synthesis using d ‐allo‐Ile in place of l ‐Ile and a different site for macrocyclization. The resulting product (d ‐allo‐Ile2)‐stylissatin A ( 1c ) was also found to have the trans‐Phe7‐Pro6 peptide conformations like rotamer 1b . Applying the second route to the synthesis of stylissatin A itself, we obtained stylissatin A natural rotamer 1a accompanied by rotamer 1b as the major product. Rotamers 1a , 1b , and the epimer 1c were separable by HPLC, and 1a was found to match the natural product in structure and biological activity. Six related analogs 2–7 of stylissatin A were synthesized on Wang resin and characterized by spectral analysis. The natural product ( 1a ), the rotamer ( 1b ), and (d ‐allo‐Ile2)‐stylissatin A ( 1c ) exhibited significant inhibition of NO.. Further investigations were focused on 1b , which also inhibited proliferation of T‐cells and inflammatory cytokine IL‐2 production. The analogs 2–7 weakly inhibited NO. production, but strongly inhibited IL‐2 cytokine production compared with synthetic peptide 1b . All analogs inhibited the proliferation of T‐cells, with analog 7 having the strongest effect. In the analogs, the Pro6 residue was replaced by Glu/Ala, and the SAR indicates that the nature of this residue plays a role in the biological function of these peptides. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
967.
Hydrogen Evolution: CdS Nanoparticle‐Decorated Cd Nanosheets for Efficient Visible Light‐Driven Photocatalytic Hydrogen Evolution (Adv. Energy Mater. 3/2016) 下载免费PDF全文
968.
Priscilla Kheddo Matthew J. Cliff Shahid Uddin Christopher F. van der Walle 《MABS-AUSTIN》2016,8(7):1245-1258
Assessing how excipients affect the self-association of monoclonal antibodies (mAbs) requires informative and direct in situ measurements for highly concentrated solutions, without sample dilution or perturbation. This study explores the application of solution nuclear magnetic resonance (NMR) spectroscopy for characterization of typical mAb behavior in formulations containing arginine glutamate. The data show that the analysis of signal intensities in 1D 1H NMR spectra, when compensated for changes in buffer viscosity, is invaluable for identifying conditions where protein-protein interactions are minimized. NMR-derived molecular translational diffusion rates for concentrated solutions are less useful than transverse relaxation rates as parameters defining optimal formulation. Furthermore, NMR reports on the solution viscosity and mAb aggregation during accelerated stability study assessment, generating data consistent with that acquired by size-exclusion chromatography. The methodology developed here offers NMR spectroscopy as a new tool providing complementary information useful to formulation development of mAbs and other large therapeutic proteins. 相似文献
969.
Sajjad Asaf Abdul Latif Khan Abdur Rahim Khan Muhammad Waqas Sang-Mo Kang Muhammad Aaqil Khan Raheem Shahzad Chang-Woo Seo Jae-Ho Shin In-Jung Lee 《PloS one》2016,11(4)
Oryza minuta (Poaceae family) is a tetraploid wild relative of cultivated rice with a BBCC genome. O. minuta has the potential to resist against various pathogenic diseases such as bacterial blight (BB), white backed planthopper (WBPH) and brown plant hopper (BPH). Here, we sequenced and annotated the complete mitochondrial genome of O. minuta. The mtDNA genome is 515,022 bp, containing 60 protein coding genes, 31 tRNA genes and two rRNA genes. The mitochondrial genome organization and the gene content at the nucleotide level are highly similar (89%) to that of O. rufipogon. Comparison with other related species revealed that most of the genes with known function are conserved among the Poaceae members. Similarly, O. minuta mt genome shared 24 protein-coding genes, 15 tRNA genes and 1 ribosomal RNA gene with other rice species (indica and japonica). The evolutionary relationship and phylogenetic analysis revealed that O. minuta is more closely related to O. rufipogon than to any other related species. Such studies are essential to understand the evolutionary divergence among species and analyze common gene pools to combat risks in the current scenario of a changing environment. 相似文献
970.
Marcel Prothmann Florian von Knobelsdorff-Brenkenhoff Agnieszka T?pper Matthias A. Dieringer Etham Shahid Andreas Graessl Jan Rieger Darius Lysiak C. Thalhammer Till Huelnhagen Peter Kellman Thoralf Niendorf Jeanette Schulz-Menger 《PloS one》2016,11(2)