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751.
Sabrina Nickel Farnusch Kaschani Tom Colby Renier A.L. van der Hoorn Markus Kaiser 《Bioorganic & medicinal chemistry》2012,20(2):601-606
Activity-based protein profiling represents a powerful methodology to probe the activity state of enzymes under various physiological conditions. Here we present the development of a para-nitrophenol phosphonate activity-based probe with structural similarities to the potent agrochemical paraoxon. We demonstrate that this probes labels distinct serine hydrolases with the carboxylesterase CXE12 as the predominant target in Arabidopsis thaliana. The designed probe features a distinct labeling pattern and therefore represents a promising chemical tool to investigate physiological roles of selected serine hydrolases such as CXE12 in plant biology. 相似文献
752.
In vivo neutralization of TNF-alpha promotes humoral autoimmunity by preventing the induction of CTL. 总被引:3,自引:0,他引:3
C S Via A Shustov V Rus T Lang P Nguyen F D Finkelman 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(12):6821-6826
Neutralization of TNF-alpha in humans with rheumatoid arthritis or Crohn's disease has been associated with the development of humoral autoimmunity. To determine the effect of TNF-alpha neutralization on cell-mediated and humoral-mediated responses, we administered anti-TNF-alpha mAb to mice undergoing acute graft-vs-host disease (GVHD) using the parent-into-F(1) model. In vivo neutralization of TNF-alpha blocked the lymphocytopenic features characteristic of acute GVHD and induced a lupus-like chronic GVHD phenotype (lymphoproliferation and autoantibody production). These effects resulted from complete inhibition of detectable antihost CTL activity and required the presence of anti-TNF-alpha mAb for the first 4 days after parental cell transfer, indicating that TNF-alpha plays a critical role in the induction of CTL. Moreover, an in vivo blockade of TNF-alpha preferentially inhibited the production of IFN-gamma and blocked IFN-gamma-dependent up-regulation of Fas; however, cytokines such as IL-10, IL-6, or IL-4 were not inhibited. These results suggest that a therapeutic TNF-alpha blockade may promote humoral autoimmunity by selectively inhibiting the induction of a CTL response that would normally suppress autoreactive B cells. 相似文献
753.
Primary structure of bovine matrix Gla protein, a new vitamin K-dependent bone protein 总被引:7,自引:0,他引:7
The complete amino acid sequence of bovine bone matrix Gla protein (MGP) was determined by automatic sequence analysis of the intact protein and of peptides isolated from tryptic and BNPS-skatole digests. This 79-residue, vitamin K-dependent protein contains a single disulfide bond and 4.8 gamma-carboxyglutamate (Gla) residues, one each at positions 37, 41, 48, and 52, and 0.8 Gla and 0.2 Glu at position 2. There is sufficient sequence homology between MGP and bone Gla protein (BGP) to indicate that these two bovine bone proteins arose by gene duplication and subsequent divergent evolution. Although MGP has a very low solubility in water compared to BGP, there is no hydrophobic domain in MGP which could account for its insolubility, and the overall fraction of hydrophobic residues is 32% for MGP compared to 43% for BGP. MGP is the first vitamin K-dependent protein to be discovered which has several non-gamma-carboxylated residues to the NH2-terminal side of its Gla residues. The presence of NH2-terminal Glu residues between the putative targeting domain for the gamma-carboxylase in the MGP leader sequence and the mid-molecule Gla residues suggests that the gamma-carboxylase may have additional, as yet unrecognized, specificity requirements which determine the susceptibility of Glu residues for gamma-carboxylation. 相似文献
754.
We have cloned and sequenced the p53-encoding cDNA of Syrian hamster. The encoded product is 78% and 75% homologous to human and mouse p53, respectively. Immunoprecipitations of the cDNA-encoded protein by monoclonal antibodies specific for mammalian p53 confirmed the identity of the protein. 相似文献
755.
K P Ossenkopp M Kavaliers F S Prato G C Teskey E Sestini M Hirst 《Life sciences》1985,37(16):1507-1514
Adult male mice exposed to a Nuclear Magnetic Resonance Imaging (NMRI) procedure during the mid-dark period and injected with morphine (10 mg/kg) failed to exhibit the normal nocturnally enhanced morphine analgesia response to a thermal stimulus that was displayed by mice exposed to a sham imaging procedure and treated with morphine (p less than .01). When tested during the mid-light period, animals exposed to the NMRI procedure and given morphine displayed attenuated analgesia levels relative to sham exposed mice (p less than .01) treated with morphine. However, the morphine induced analgesia was not totally abolished since the imaged mice still exhibited analgesia relative to saline treated mice (p less than .01). These results suggest that the magnetic and/or radio-frequency fields associated with the NMRI procedure alter both day- and night-time responses to morphine. These results may reflect magnetic field induced alterations in neuronal calcium binding and/or alterations in nocturnal pineal gland activity. 相似文献
756.
Spatial frequency tuned channels: implications for structure and function from psychophysical and computational studies of stereopsis 总被引:1,自引:0,他引:1
J P Frisby J E Mayhew 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1980,290(1038):95-116
Various psychophysical experiments investigating the role of spatial frequency tuned channels in stereopsis are reviewed and a computational model of stereopsis deriving from these studies is described. The distinctive features of the model are: (1) it identifies edge locations in each monocular field by searching for zero crossings in non-orientated centre-surround convolution profiles; (2) it selects among all possible binocular point-for-point combinations of edge locations only those which satisfy a (quasi-) collinear figural grouping rule; (3) it presents a concept of the orientated and spatial frequency tuned channel as a nonlinear grouping operator. The success of the model is demonstrated both on a stereo pair of a natural scene and on a random-dot stereogram. 相似文献
757.
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759.
760.
P.Mick Richardson 《Biochemical Systematics and Ecology》1982,10(2):197-199
Published results of the distribution of anthocyanins in the Sterculiaceae have been re-interpreted on the basis of the phylogenetic status of the compounds present. A flavonoid score system was less useful than a cladistic interpretation based on Hennigian arguments. 相似文献