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461.
Khouangsathiene S Pearson C Street S Ferguson B Dubay C 《Bioinformatics (Oxford, England)》2008,24(22):2645-2646
MonkeySNP is a web-based resource created by the Genetic Resource and Informatics Program at the Oregon National Primate Research Center to facilitate access to non-human primate (NHP) single nucleotide polymorphisms (SNP) data. MonkeySNP is a mirror of the NCBI dbSNP database and contains additional NHP subpopulation genotype data and visual genotype displays to support SNP review and selection. AVAILABILITY: http://monkeysnp.ohsu.edu/snp/ SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online. 相似文献
462.
Gopalakrishnan SM Mammen B Schmidt M Otterstaetter B Amberg W Wernet W Kofron JL Burns DJ Warrior U 《Journal of biomolecular screening》2005,10(1):46-55
Although fluorescence imaging plate reader (FLIPR)-based assays have been widely used in high-throughput screening, improved efficiencies in throughput and fidelity continue to be investigated. This study presents an offline compound addition protocol coupled with a testing strategy using mixtures of compounds in a 384-well format to identify antagonists of the neurokinin-1 receptor expressed in the human astrocytoma cell line (U373 MG). Substance P evoked a concentration-dependent increase in intracellular cellular Ca(2+) with an EC(50) value of 0.30 +/- 0.17 nM, which was inhibited by neurokinin-1 (NK1) antagonists L-733,060 and L-703,606. Test compounds, as mixtures of 10 compounds/well, were added to the cells offline using an automated dispensing unit and incubated prior to performing the assay in the FLIPR. Using the offline protocol, a higher through put of ~200,000 compounds was achieved in an 8-h working day, and several novel structural classes of compounds were identified as antagonists for the NK1 receptor. These studies demonstrate that the offline compound addition format using a mixture of compounds in a 384-well FLIPR assay provides an efficient platform for screening and identifying modulators for G-protein-coupled receptors. 相似文献
463.
464.
Peterson FC Lytle BL Sampath S Vinarov D Tyler E Shahan M Markley JL Volkman BF 《Protein science : a publication of the Protein Society》2005,14(8):2195-2200
Present in virtually every species, thioredoxins catalyze disulfide/dithiol exchange with various substrate proteins. While the human genome contains a single thioredoxin gene, plant thioredoxins are a complex protein family. A total of 19 different thioredoxin genes in six subfamilies has emerged from analysis of the Arabidopsis thaliana genome. Some function specifically in mitochondrial and chloroplast redox signaling processes, but target substrates for a group of eight thioredoxin proteins comprising the h subfamily are largely uncharacterized. In the course of a structural genomics effort directed at the recently completed A. thaliana genome, we determined the structure of thioredoxin h1 (At3g51030.1) in the oxidized state. The structure, defined by 1637 NMR-derived distance and torsion angle constraints, displays the conserved thioredoxin fold, consisting of a five-stranded beta-sheet flanked by four helices. Redox-dependent chemical shift perturbations mapped primarily to the conserved WCGPC active-site sequence and other nearby residues, but distant regions of the C-terminal helix were also affected by reduction of the active-site disulfide. Comparisons of the oxidized A. thaliana thioredoxin h1 structure with an h-type thioredoxin from poplar in the reduced state revealed structural differences in the C-terminal helix but no major changes in the active site conformation. 相似文献
465.
Mancl ME Hu G Sangster-Guity N Olshalsky SL Hoops K Fitzgerald-Bocarsly P Pitha PM Pinder K Barnes BJ 《The Journal of biological chemistry》2005,280(22):21078-21090
466.
467.
Cheshenko N Del Rosario B Woda C Marcellino D Satlin LM Herold BC 《The Journal of cell biology》2003,163(2):283-293
The cellular pathways required for herpes simplex virus (HSV) invasion have not been defined. To test the hypothesis that HSV entry triggers activation of Ca2+-signaling pathways, the effects on intracellular calcium concentration ([Ca2+]i) after exposure of cells to HSV were examined. Exposure to virus results in a rapid and transient increase in [Ca2+]i. Pretreatment of cells with pharmacological agents that block release of inositol 1,4,5-triphosphate (IP3)-sensitive endoplasmic reticulum stores abrogates the response. Moreover, treatment of cells with these pharmacological agents inhibits HSV infection and prevents focal adhesion kinase (FAK) phosphorylation, which occurs within 5 min after viral infection. Viruses deleted in glycoprotein L or glycoprotein D, which bind but do not penetrate, fail to induce a [Ca2+]i response or trigger FAK phosphorylation. Together, these results support a model for HSV infection that requires activation of IP3-responsive Ca2+-signaling pathways and that is associated with FAK phosphorylation. Defining the pathway of viral invasion may lead to new targets for anti-viral therapy. 相似文献
468.
The Bacillus halodurans voltage-gated sodium-selective channel (NaChBac) (Ren, D., B. Navarro, H. Xu, L. Yue, Q. Shi, and D.E. Clapham. 2001b. SCIENCE: 294:2372-2375), is an ideal candidate for high resolution structural studies because it can be expressed in mammalian cells and its functional properties studied in detail. It has the added advantage of being a single six transmembrane (6TM) orthologue of a single repeat of mammalian voltage-gated Ca(2+) (Ca(V)) and Na(+) (Na(V)) channels. Here we report that six amino acids in the pore domain (LESWAS) participate in the selectivity filter. Replacing the amino acid residues adjacent to glutamatic acid (E) by a negatively charged aspartate (D; LEDWAS) converted the Na(+)-selective NaChBac to a Ca(2+)- and Na(+)-permeant channel. When additional aspartates were incorporated (LDDWAD), the mutant channel resulted in a highly expressing voltage-gated Ca(2+)-selective conductance. 相似文献
469.
Kalns J Morris J Eggers J Kiel J 《Biochemical and biophysical research communications》2002,297(3):506-509
Blk57/B6 mice were infected with LD90 dose of Sterne strain anthrax spores subcutaneously and then treated with doxycycline. Doxycycline at a dose of 1.5mg/kg, by intra-peritoneal injection, protected mice from death when given at the same time as spores. When doxycycline administration was delayed 4h survival is 90%. Delay of 24h increased survival time but had no impact on eventual mortality. When doxycycline was delayed 48h, mortality and time to death were comparable to sham injection. Peritoneal macrophages harvested from Blk57/B6 mice were examined for response to anthrax lethal toxin and are shown to be deficient in their ability to produce TNF-alpha and have increased expression of IL-6 compared to RAW 264.7 murine macrophage cell line. These findings suggest that antibiotic therapy has limited effects following lethal anthrax spore challenge, even when the host is of a phenotype that does not produce TNF-alpha in response to anthrax lethal toxin exposure. 相似文献
470.
Press M Spaulding B Groshen S Kaminsky D Hagerty M Sherman L Christensen K Edwards DP 《Steroids》2002,67(9):799-813
Monoclonal antibodies directed against human estrogen receptor (ER) and progesterone receptor (PR) have been used extensively for biochemical and immunohistochemical detection of receptors independent of hormone-binding assays. These antibodies have been valuable both for experimental work and for detection of receptors in clinical breast cancer specimens. The purpose of this study was to characterize the sensitivity and specificity of different antibodies for detection of PR by immunohistochemistry (IHC) of formalin-fixed paraffin breast carcinoma sections. The panel of twelve antibodies included two new ones (PgR636 and PgR1294) produced prospectively to be resistant to formalin fixation and paraffin embedding. Fifty-nine breast carcinomas, having known PR levels by biochemical ligand-binding assay, were used to prepare multitumor paraffin-embedded tissue blocks for characterization of the PR antibodies. Of all the antibodies tested, both PgR636 and PgR1294 stained the highest percentage of breast carcinomas known to be positive by the biochemical assay (95-98%) and they exhibited the highest concordance with the biochemical assay (88-90%). The PgR636 and PgR1294 antibodies, along with one other, PR 88, also gave the highest intensity of nuclear staining, while PgR636 and PgR1294 stained the highest mean percentage of tumor cell nuclei. Antigen retrieval was not necessary for PR immunostaining by PgR636 and PgR1294 in most tumors and other tissues examined, but did slightly increase the staining intensity. The majority of the other antibodies tested were highly dependent on antigen retrieval; only PR 88 and KD 68 antibodies approached the performance of PgR636 and PgR1294 without antigen retrieval. These results indicate that PgR636 and PgR1294 are optimal antibodies for IHC detection of PR in routine paraffin tissue blocks. 相似文献