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排序方式: 共有209条查询结果,搜索用时 15 毫秒
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Daniela Stokmaier Oleg Khorev Brian Cutting Rita Born Daniel Ricklin Thomas O.G. Ernst Fabienne Böni Kathrin Schwingruber Martin Gentner Matthias Wittwer Morena Spreafico Angelo Vedani Said Rabbani Oliver Schwardt Beat Ernst 《Bioorganic & medicinal chemistry》2009,17(20):7254-7264
A series of novel aryl-substituted triazolyl d-galactosamine derivatives was synthesized as ligands for the carbohydrate recognition domain of the major subunit H1 (H1-CRD) of the human asialoglycoprotein receptor (ASGP-R). The compounds were biologically evaluated with a newly developed competitive binding assay, surface plasmon resonance and by a competitive NMR binding experiment. With compound 1b, a new ligand with a twofold improved affinity to the best so far known d-GalNAc was identified. This small, drug-like ligand can be used as targeting device for drug delivery to hepatocytes. 相似文献
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Roney S Coimbra Veronique Voisin Antoine B de Saizieu Raija LP Lindberg Matthias Wittwer David Leppert Stephen L Leib 《BMC biology》2006,4(1):15-18
Background
Pneumococcal meningitis is associated with high mortality (~30%) and morbidity. Up to 50% of survivors are affected by neurological sequelae due to a wide spectrum of brain injury mainly affecting the cortex and hippocampus. Despite this significant disease burden, the genetic program that regulates the host response leading to brain damage as a consequence of bacterial meningitis is largely unknown. 相似文献44.
Alpha2-macroglobulin is a novel substrate for ADAMTS-4 and ADAMTS-5 and represents an endogenous inhibitor of these enzymes 总被引:4,自引:0,他引:4
Tortorella MD Arner EC Hills R Easton A Korte-Sarfaty J Fok K Wittwer AJ Liu RQ Malfait AM 《The Journal of biological chemistry》2004,279(17):17554-17561
Osteoarthritis is characterized by the loss of aggrecan and collagen from the cartilage extracellular matrix. The proteinases responsible for the breakdown of cartilage aggrecan include ADAMTS-4 (aggrecanase 1) and ADAMTS-5 (aggrecanase 2). Post-translational inhibition of ADAMTS-4/-5 activity may be important for maintaining normal homeostasis of aggrecan metabolism, and thus, any disruption to this inhibition could lead to accelerated aggrecan breakdown. To date TIMP-3 (tissue inhibitor of matrix metalloproteinases-3) is the only endogenous inhibitor of ADAMTS-4/-5 that has been identified. In the present studies we identify alpha(2)-macroglobulin (alpha(2)M) as an additional endogenous inhibitor of ADAMTS-4 and ADAMTS-5. alpha(2)M inhibited the activity of both ADAMTS-4 and ADAMTS-5 in a concentration-dependent manner, demonstrating 1:1 stoichiometry with second-order rate constants on the order of 10(6) and 10(5) m(-1) s(-1), respectively. Inhibition of the aggrecanases was mediated by proteolysis of the bait region within alpha(2)M, resulting in physical entrapment of these proteinases. Both ADAMTS-4 and ADAMTS-5 cleaved alpha(2)M at Met(690)/Gly(691), representing a novel proteinase cleavage site within alpha(2)M and a novel site of cleavage for ADAMTS-4 and ADAMTS-5. Finally, the use of the anti-neoepitope antibodies to detect aggrecanase-generated alpha(2)M-fragments in synovial fluid was investigated and found to be uninformative. 相似文献
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Genotyping of Human and Porcine Yersinia enterocolitica, Yersinia intermedia, and Yersinia bercovieri Strains from Switzerland by Amplified Fragment Length Polymorphism Analysis 下载免费PDF全文
Kathrin Kuehni Boghenbor Stephen L. W. On Branko Kokotovic Andreas Baumgartner Trudy M. Wassenaar Matthias Wittwer Beatrice Bissig-Choisat Joachim Frey 《Applied microbiology》2006,72(6):4061-4066
In this study, 231 strains of Yersinia enterocolitica, 25 strains of Y. intermedia, and 10 strains of Y. bercovieri from human and porcine sources (including reference strains) were analyzed using amplified fragment length polymorphism (AFLP), a whole-genome fingerprinting method for subtyping bacterial isolates. AFLP typing distinguished the different Yersinia species examined. Representatives of Y. enterocolitica biotypes 1A, 1B, 2, 3, and 4 belonged to biotype-related AFLP clusters and were clearly distinguished from each other. Y. enterocolitica biotypes 2, 3, and 4 appeared to be more closely related to each other (83% similarity) than to biotypes 1A (11%) and 1B (47%). Biotype 1A strains exhibited the greatest genetic heterogeneity of the biotypes studied. The biotype 1A genotypes were distributed among four major clusters, each containing strains from both human and porcine sources, confirming the zoonotic potential of this organism. The AFLP technique is a valuable genotypic method for identification and typing of Y. enterocolitica and other Yersinia spp. 相似文献
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Localized upregulation of a new expansin gene predicts the site of leaf formation in the tomato meristem. 总被引:18,自引:3,他引:15 下载免费PDF全文
Expansins are extracellular proteins that increase plant cell wall extensibility in vitro and are thought to be involved in cell expansion. We showed in a previous study that administration of an exogenous expansin protein can trigger the initiation of leaflike structures on the shoot apical meristem of tomato. Here, we studied the expression patterns of two tomato expansin genes, LeExp2 and LeExp18. LeExp2 is preferentially expressed in expanding tissues, whereas LeExp18 is expressed preferentially in tissues with meristematic activity. In situ hybridization experiments showed that LeExp18 expression is elevated in a group of cells, called I1, which is the site of incipient leaf primordium initiation. Thus, LeExp18 expression is a molecular marker for leaf initiation, predicting the site of primordium formation at a time before histological changes can be detected. We propose a model for the regulation of phyllotaxis that postulates a crucial role for expansin in leaf primordium initiation. 相似文献
48.
Arthur J. Wittwer Linda S. Carr John Zagorski Gregory J. Dolecki Barbara A. Crippes Joseph E. De Larco 《Journal of cellular physiology》1993,156(2):421-427
Significant levels of cytokine-induced neutrophil chemoattractant (CINC) were found in serum-free medium conditioned by a highly metastatic rat cell line, RC20. To study CINC's role in inflammation and metastasis, CINC was purified from this source for use in in vitro assays and for antibody production in goats and rabbits. CINC was a potent chemoattractant for rat neutrophils (EC-50 0.5 nM). A fusion protein of glutathione-S-transferase and CINC (GST-CINC) was produced in E. coli. Anti-CINC polyclonal IgG was purified from immune goat and rabbit sera by protein A and GST-CINC affinity chromatography. Both goat and rabbit anti-CINC antibody preparations at 4 μg/mL (an 11-fold molar excess) were found to completely block the activity of 2.5 nM CINC in a rat neutrophil chemotaxis assay. These antibodies have been used to develop a sensitive immunoassay for CINC. The availability of large amounts of affinity-purified blocking anti-CINC antibody will allow investigations into the role played by CINC in rodent inflammation models and in the metastasis of RC20 cells. © 1993 Wiley-Liss, Inc. 相似文献
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