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121.
Tomoyuki Ohe Ryutaro Umezawa Yumina Kitagawara Daisuke Yasuda Kyoko Takahashi Shigeo Nakamura Akiko Abe Shuichi Sekine Kousei Ito Kentaro Okunushi Hanae Morio Tomomi Furihata Naohiko Anzai Tadahiko Mashino 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3708-3711
We synthesized six novel BBR derivatives that were designed to avoid metabolic activation via ipso-substitution and evaluated for their degree of toxicity and hURAT1 inhibition. It was found that all of the derivatives demonstrate lower cytotoxicity in mouse hepatocytes and lower levels of metabolic activation than BBR, while maintaining their inhibitory activity toward the uric acid transporter. We propose that these derivatives could serve as effective uricosuric agents that have much better safety profiles than BBR. 相似文献
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123.
Nanako Takeda-Hirokawa Lian-pin Neoh Hiroaki Akimoto Hiroshi Kaneko Takashi Hishikawa Iwao Sekigawa Hiroshi Hashimoto Shun-ichi Hirose Tsutomu Murakami Naoki Yamamoto Tohru Mimura Yutaro Kaneko 《Microbiology and immunology》1997,41(9):741-745
To clarify the mechanism by which curdlan sulfate (CRDS) inhibits human immunodeficiency virus (HIV)-1 infection, we examined its influence on the binding of gp120 to CD4 molecules on T cells and macrophages, as well as on the production of TNF-α by gp120-stimulated macrophages (which promotes HIV-1 replication). CRDS treatment of cells not only inhibited the binding of HIV-1 gp120 to CD4+ cells, but also inhibited TNF-α production induced by gp120. Inhibition of HIV-1 infection by CRDS may be related to these two actions. 相似文献
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Takahashi K Chibazakura T Sekine Y Yoshikawa H 《Biochemical and biophysical research communications》2007,355(2):426-430
While most studies involving transposition have focused on analyzing the detailed mechanisms of transposition, the cellular conditions under which transposition occurs remain to be elucidated. In Escherichia coli, papillation assay is a powerful tool for transpositional analysis and the isolation of mutants affecting transposition. On the other hand, while our assay system based on the E. coli papillation assay can detect transpositional events in Bacillus subtilis 168, it is not suitable for quantitating transposition frequency because blue papillae on the transposant colonies of B. subtilis are not countable. We succeeded in developing a new "GFP hop-on assay" system that facilitates quantitative detection of the transposition of the FACS-optimized GFP mutant gene. Our assay system is a step forward in understanding the cellular conditions under which transposition occurs. 相似文献
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128.
Induction of human beta-defensin-2 mRNA expression by Helicobacter pylori in human gastric cell line MKN45 cells on cag pathogenicity island. 总被引:2,自引:0,他引:2
A Wada N Mori K Oishi H Hojo Y Nakahara Y Hamanaka M Nagashima I Sekine K Ogushi T Niidome T Nagatake J Moss T Hirayama 《Biochemical and biophysical research communications》1999,263(3):770-774
Helicobacter pylori is an etiological agent of gastritis, peptic ulcer, and gastric cancer. Human beta-defensin-2 (hBD-2) is an antimicrobial peptide which belongs to one of the most important host defense systems against bacterial infection in several epithelial tissues. We studied the effect of H. pylori on the expression of hBD-2 mRNA in MKN45 gastric mucosal cells. H. pylori, but not culture filtrate, increased the hBD-2 mRNA level in MKN45 cells; the inductive effect of H. pylori was not detected with Intestine 407 cells. Among H. pylori strains, strain OHPC0002, which lacks a cag Pathogenicity Island (PAI), did not induce hBD-2 mRNA in MKN45 cells. These results suggested that H. pylori cag PAI is critical for the induction of hBD-2 mRNA in MKN45 cells. Exposure of MKN45 cells to Salmonella typhimurium, S. enteritidis, S. typhi, and S. dublin, but not Escherichia coli ML35, also resulted in induction of hBD-2 mRNA. 相似文献
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