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971.
972.
973.
Yoshikawa M Matsuda H Morikawa T Xie H Nakamura S Muraoka O 《Bioorganic & medicinal chemistry》2006,14(22):7468-7475
The methanolic extract from the dried stems of Cistanche tubulosa (Schrenk) R. Wight was found to show an inhibitory effect on contractions induced by noradrenaline in isolated rat aortic strips. From the extract, new phenylethanoid oligoglycoside constituents, kankanosides F and G, and an acylated oligosugar, kankanose, were isolated together with 14 known compounds. The structures of these new compounds were determined on the basis of their chemical and physicochemical evidence. In addition, principal constituents, kankanoside F, kankanose, echinacoside, acteoside, and cistanoside F, showed vasorelaxant activity, and several structural requirements for the activity were clarified. 相似文献
974.
Yoshikawa M Nishida N Ninomiya K Ohgushi T Kubo M Morikawa T Matsuda H 《Bioorganic & medicinal chemistry》2006,14(2):456-463
The methanolic extract (200 mg/kg, p.o. and i.p.), principal coumarin constituents (isoepoxypteryxin, anomalin, and praeroside IV), and a polyacetylene constituent (falcarindiol) (25 mg/kg, i.p.) from the roots of Angelica furcijuga protected the liver injury induced by D-galactosamine (D-GalN)/lipopolysaccharide (LPS) in mice. In in vitro experiments, coumarin constituents (hyuganins A-D, anomalin, pteryxin, isopteryxin, and suksdorfin) and polyacetylene constituents [(-)-falcarinol and falcarindiol] substantially inhibited LPS-induced NO and/or TNF-alpha production in mouse peritoneal macrophages, and isoepoxypteryxin inhibited D-GalN-induced cytotoxicity in primary cultured rat hepatocytes. Furthermore, hyuganin A, anomalin, and isopteryxin inhibited the decrease in cell viability by TNF-alpha in L929 cells. 相似文献
975.
Kazuo Nakamichi Mutsuyo Takayama‐Ito Souichi Nukuzuma Ichiro Kurane Masayuki Saijo 《Microbiology and immunology》2010,54(8):475-482
Murine polyomavirus is used in various models of persistent virus infection. This study was undertaken to assess the spatial and temporal patterns of MPyV infection in the brains of immunocompetent (BALB/c) and immunocompromised (KSN nude) mice. MPyV was stereotaxically microinfused into the brain parenchyma, and the kinetics of infection were examined by quantitative PCR. In BALB/c mice, the amount of viral DNA in the brain peaked at 4 days p.i. and then rapidly diminished. In contrast, MPyV DNA levels increased up to 4 days and then gradually decreased over the 30‐day observation period in the brain of KSN mice. In both mouse strains, viral DNA was readily detected around the sites of inoculation from 2 to 6 days p.i., and continued to be detected for up to 30 days p.i. In addition, MPyV infection did not lead to a drastic induction of innate immune response in the brains, nor did MPyV‐inoculated mice show any signs of disease. These results indicate that MPyV establishes an asymptomatic long‐term infection in the mouse brain. 相似文献
976.
Connective tissue growth factor is a substrate of ADAM28 总被引:1,自引:0,他引:1
Mochizuki S Tanaka R Shimoda M Onuma J Fujii Y Jinno H Okada Y 《Biochemical and biophysical research communications》2010,402(4):651-657
ADAM28, a member of the ADAM (a disintegrin and metalloproteinase) gene family, is over-expressed by carcinoma cells and the expression correlates with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, information about substrates of ADAM28 is limited. We screened interacting molecules of ADAM28 in human lung cDNA library by yeast two-hybrid system and identified connective tissue growth factor (CTGF). Binding of CTGF to proADAM28 was demonstrated by yeast two-hybrid assay and protein binding assay. ADAM28 cleaved CTGF in dose- and time-dependent manners at the Ala181-Tyr182 and Asp191-Pro192 bonds in the hinge region of the molecule. ADAM28 selectively digested CTGF in the complex of CTGF and vascular endothelial growth factor165 (VEGF165), releasing biologically active VEGF165 from the complex. RT-PCR and immunohistochemical analyses demonstrated that ADAM28, CTGF and VEGF are commonly co-expressed in the breast carcinoma tissues. These data provide the first evidence that CTGF is a novel substrate of ADAM28 and suggest that ADAM28 may promote VEGF165-induced angiogenesis in the breast carcinomas by the CTGF digestion in the CTGF/VEGF165 complex. 相似文献
977.
Sugar transporters in efficient utilization of mixed sugar substrates: current knowledge and outlook
Toru Jojima Crispinus A. Omumasaba Masayuki Inui Hideaki Yukawa 《Applied microbiology and biotechnology》2010,85(3):471-480
There is increasing interest in production of transportation fuels and commodity chemicals from lignocellulosic biomass, most
desirably through biological fermentation. Considerable effort has been expended to develop efficient biocatalysts that convert
sugars derived from lignocellulose directly to value-added products. Glucose, the building block of cellulose, is the most
suitable fermentation substrate for industrial microorganisms such as Escherichia coli, Corynebacterium glutamicum, and Saccharomyces cerevisiae. Other sugars including xylose, arabinose, mannose, and galactose that comprise hemicellulose are generally less efficient
substrates in terms of productivity and yield. Although metabolic engineering including introduction of functional pentose-metabolizing
pathways into pentose-incompetent microorganisms has provided steady progress in pentose utilization, further improvements
in sugar mixture utilization by microorganisms is necessary. Among a variety of issues on utilization of sugar mixtures by
the microorganisms, recent studies have started to reveal the importance of sugar transporters in microbial fermentation performance.
In this article, we review current knowledge on diversity and functions of sugar transporters, especially those associated
with pentose uptake in microorganisms. Subsequently, we review and discuss recent studies on engineering of sugar transport
as a driving force for efficient bioconversion of sugar mixtures derived from lignocellulose. 相似文献
978.
Miho Sasaki Toru Jojima Masayuki Inui Hideaki Yukawa 《Applied microbiology and biotechnology》2010,86(4):1057-1066
Wild-type Corynebacterium glutamicum produced 0.6 g l−1 xylitol from xylose at a productivity of 0.01 g l−1 h−1 under oxygen deprivation. To increase this productivity, the pentose transporter gene (araE) from C. glutamicum ATCC31831 was integrated into the C. glutamicum R chromosome. Consequent disruption of its lactate dehydrogenase gene (ldhA), and expression of single-site mutant xylose reductase from Candida tenuis (CtXR (K274R)) resulted in recombinant C. glutamicum strain CtXR4 that produced 26.5 g l−1 xylitol at 3.1 g l−1 h−1. To eliminate possible formation of toxic intracellular xylitol phosphate, genes encoding xylulokinase (XylB) and phosphoenolpyruvate-dependent
fructose phosphotransferase (PTSfru) were disrupted to yield strain CtXR7. The productivity of strain CtXR7 increased 1.6-fold over that of strain CtXR4. A fed-batch
21-h CtXR7 culture in mineral salts medium under oxygen deprivation yielded 166 g l−1 xylitol at 7.9 g l−1 h−1, representing the highest bacterial xylitol productivity reported to date. 相似文献
979.
980.
Kenji Matsuno Kazushige Takai Yoshinobu Isaka Yuka Unno Masayuki Sato Osamu Takikawa Akira Asai 《Bioorganic & medicinal chemistry letters》2010,20(17):5126-5129
S-Benzylisothiourea 3a was discovered by its ability to inhibit indoleamine-2,3-dioxygenase (IDO) in our screening program. Subsequent optimization of the initial hit 3a lead to the identification of sub-μM inhibitors 3r and 10h, both of which suppressed kynurenine production in A431 cells. Synthesis and structure–activity relationship of S-benzylisothiourea analogues as small-molecule inhibitors of IDO are described. 相似文献