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91.
Singh VP Singh S Narang KK Bhattacharya D 《Journal of enzyme inhibition and medicinal chemistry》2009,24(1):105-110
Complexes of the type [Al(HL)(OH)Cl(2)], [M(HL)(OH)(2)Cl] and [M'(HL)(L')(OH)Cl], where HL = 5-iodouracil; HL' = histidine; M = Cr(III), Fe(III) and M' = Al(III), Cr(III), Fe(III), were synthesized and characterized. The complexes are polymeric showing high decomposition points and are insoluble in water and common organic solvents. The mu(eff) values, electronic spectral bands and ESR spectra suggest a polymeric 6-coordinate spin-free octahedral stereochemistry for the Cr(III) and Fe(III) complexes. 5-Iodouracil acts as a monodentate ligand coordinating to the metal ion through the O atom of C((4)) = O while histidine through the O atom of -COO(- ) and the N atom of -NH(2) group. In vivo antitumour effect of 5-iodouracil and its complexes was examined on C(3)H /He mice against P815 murine mastocytoma. As evident from their T/C values, Cr(III) and Fe(III) complexes display significant and higher antitumour activity compared to the 5-iodouracil ligand. The in vitro results of the complexes on the same cells indicate that Cr(III) and Fe(III) complexes show higher inhibition on (3)H-thymidine and (3)H-uridine incorporation in DNA and RNA replication, respectively, at a dose of 5 microg/mL. 相似文献
92.
Studies were carried out on derivatisation of bagasse into an ion exchange material and application of this chemically modified bagasse in the treatment of distillery wastewater. It was found that CHPTAC bagasse with HCl treatment and DEAE-bagasse in its free base form were most effective in colour removal and the mechanism of colour removal indicated significant contribution of both, the conventional ion exchange and the chemical sorption. 相似文献
93.
Structure of severe acute respiratory syndrome coronavirus receptor-binding domain complexed with neutralizing antibody 总被引:5,自引:0,他引:5
Prabakaran P Gan J Feng Y Zhu Z Choudhry V Xiao X Ji X Dimitrov DS 《The Journal of biological chemistry》2006,281(23):15829-15836
The severe acute respiratory syndrome coronavirus (SARS-CoV, or SCV), which caused a world-wide epidemic in 2002 and 2003, binds to a receptor, angiotensin-converting enzyme 2 (ACE2), through the receptor-binding domain (RBD) of its envelope (spike, S) glycoprotein. The RBD is very immunogenic; it is a major SCV neutralization determinant and can elicit potent neutralizing antibodies capable of out-competing ACE2. However, the structural basis of RBD immunogenicity, RBD-mediated neutralization, and the role of RBD in entry steps following its binding to ACE2 have not been elucidated. By mimicking immune responses with the use of RBD as an antigen to screen a large human antibody library derived from healthy volunteers, we identified a novel potent cross-reactive SCV-neutralizing monoclonal antibody, m396, which competes with ACE2 for binding to RBD, and determined the crystal structure of the RBD-antibody complex at 2.3-A resolution. The antibody-bound RBD structure is completely defined, revealing two previously unresolved segments (residues 376-381 and 503-512) and a new disulfide bond (between residues 378 and 511). Interestingly, the overall structure of the m396-bound RBD is not significantly different from that of the ACE2-bound RBD. The antibody epitope is dominated by a 10-residue-long protruding beta6-beta7 loop with two putative ACE2-binding hotspot residues (Ile-489 and Tyr-491). These results provide a structural rationale for the function of a major determinant of SCV immunogenicity and neutralization, the development of SCV therapeutics based on the antibody paratope and epitope, and a retrovaccinology approach for the design of anti-SCV vaccines. The available structural information indicates that the SCV entry may not be mediated by ACE2-induced conformational changes in the RBD but may involve other conformational changes or/and yet to be identified coreceptors. 相似文献
94.
Mavromatis K Abt B Brambilla E Lapidus A Copeland A Deshpande S Nolan M Lucas S Tice H Cheng JF Han C Detter JC Woyke T Goodwin L Pitluck S Held B Brettin T Tapia R Ivanova N Mikhailova N Pati A Liolios K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2010,2(3):290-299
Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
95.
Huttunen R Shweta Martikkala E Lahdenranta M Virta P Hänninen P Härmä H 《Analytical biochemistry》2011,415(1):27-31
Homogeneous luminescence-based microplate assays are desirable in high-throughput screening of new nuclear receptor regulators. Time-resolved fluorescence resonance energy transfer (TR–FRET) assays provide high sensitivity due to low background signal. The TR–FRET concept requires labeling of both ligand and receptor, making the assay format and its development relatively expensive and complex compared with single-label methods. To overcome the limitations of the multilabel methods, we have developed a single-label method for estrogen receptor (ER)–ligand binding based on quenching resonance energy transfer (QRET), where estradiol labeled with luminescent europium(III) chelate (Eu–E2) is quenched using soluble quencher molecules. The luminescence signal of Eu–E2 on binding to full-length ER is protected from quenching while increasing competitor concentrations displace Eu–E2 from the receptor, reducing the signal. The QRET method was paralleled with a commercial fluorescence polarization (FP) assay. The measured signal-to-background (S/B) values for estradiol, estrone, fulvestrant, and tamoxifen obtained for the QRET assay (5.8–9.2) were clearly higher than the S/B values for the FP assay (1.3–1.5). A Kd value of 30 nM was calculated for binding of Eu–E2 to ER from a saturation binding isotherm. The QRET method provides an attractive new single-label assay format for nuclear receptor ligand screening. 相似文献
96.
Yurlova L Kahya N Aggarwal S Kaiser HJ Chiantia S Bakhti M Pewzner-Jung Y Ben-David O Futerman AH Brügger B Simons M 《Biophysical journal》2011,101(11):2713-2720
Rapid conduction of nerve impulses requires coating of axons by myelin sheaths, which are multilamellar, lipid-rich membranes produced by oligodendrocytes in the central nervous system. To act as an insulator, myelin has to form a stable and firm membrane structure. In this study, we have analyzed the biophysical properties of myelin membranes prepared from wild-type mice and from mouse mutants that are unable to form stable myelin. Using C-Laurdan and fluorescence correlation spectroscopy, we find that lipids are tightly organized and highly ordered in myelin isolated from wild-type mice, but not from shiverer and ceramide synthase 2 null mice. Furthermore, only myelin lipids from wild-type mice laterally segregate into physically distinct lipid phases in giant unilamellar vesicles in a process that requires very long chain glycosphingolipids. Taken together, our findings suggest that oligodendrocytes exploit the potential of lipids to self-segregate to generate a highly ordered membrane for electrical insulation of axons. 相似文献
97.
98.
99.
Divekar AA Dubey S Gangalum PR Singh RR 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(2):924-930
Systemic lupus erythematosus is a chronic autoimmune disease characterized by loss of tolerance to self-Ags and activation of autoreactive T cells. Regulatory T (Treg) cells play a critical role in controlling the activation of autoreactive T cells. In this study, we investigated mechanisms of potential Treg cell defects in systemic lupus erythematosus using MRL-Fas(lpr/lpr) (MRL/lpr) and MRL-Fas(+/+) mouse models. We found a significant increase in CD4(+)CD25(+)Foxp3(+) Treg cells, albeit with an altered phenotype (CD62L(-)CD69(+)) and with a reduced suppressive capacity, in the lymphoid organs of MRL strains compared with non-autoimmune C3H/HeOuj mice. A search for mechanisms underlying the altered Treg cell phenotype in MRL/lpr mice led us to find a profound reduction in Dicer expression and an altered microRNA (miRNA, miR) profile in MRL/lpr Treg cells. Despite having a reduced level of Dicer, MRL/lpr Treg cells exhibited a significant overexpression of several miRNAs, including let-7a, let-7f, miR-16, miR-23a, miR-23b, miR-27a, and miR-155. Using computational approaches, we identified one of the upregulated miRNAs, miR-155, that can target CD62L and may thus confer the altered Treg cell phenotype in MRL/lpr mice. In fact, the induced overexpression of miR-155 in otherwise normal (C3H/HeOuj) Treg cells reduced their CD62L expression, which mimics the altered Treg cell phenotype in MRL/lpr mice. These data suggest a role of Dicer and miR-155 in regulating Treg cell phenotype. Furthermore, simultaneous appearance of Dicer insufficiency and miR-155 overexpression in diseased mice suggests a Dicer-independent alternative mechanism of miRNA regulation under inflammatory conditions. 相似文献
100.
Amit Kumar Srivastava Rupali Chopra Shafat Ali Shweta Aggarwal Lovekesh Vig Rameshwar Nath Koul Bamezai 《Nucleic acids research》2014,42(15):e122
Inundation of evolutionary markers expedited in Human Genome Project and 1000 Genome Consortium has necessitated pruning of redundant and dependent variables. Various computational tools based on machine-learning and data-mining methods like feature selection/extraction have been proposed to escape the curse of dimensionality in large datasets. Incidentally, evolutionary studies, primarily based on sequentially evolved variations have remained un-facilitated by such advances till date. Here, we present a novel approach of recursive feature selection for hierarchical clustering of Y-chromosomal SNPs/haplogroups to select a minimal set of independent markers, sufficient to infer population structure as precisely as deduced by a larger number of evolutionary markers. To validate the applicability of our approach, we optimally designed MALDI-TOF mass spectrometry-based multiplex to accommodate independent Y-chromosomal markers in a single multiplex and genotyped two geographically distinct Indian populations. An analysis of 105 world-wide populations reflected that 15 independent variations/markers were optimal in defining population structure parameters, such as FST, molecular variance and correlation-based relationship. A subsequent addition of randomly selected markers had a negligible effect (close to zero, i.e. 1 × 10−3) on these parameters. The study proves efficient in tracing complex population structures and deriving relationships among world-wide populations in a cost-effective and expedient manner. 相似文献