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991.
Kwon DJ Bae YS Ju SM Goh AR Youn GS Choi SY Park J 《Biochemical and biophysical research communications》2012,417(4):1254-1259
Casuarinin is a naturally occurring tannin that is isolated from the leaves of Hippophae rhamnoides. It has been shown to have anti-oxidant, anti-cancer, anti-viral, and anti-inflammatory activities. The aim of this study was to investigate the possible mechanism by which casuarinin inhibits TNF-α/IFN-γ-induced Th2 chemokines expression in the human keratinocytes cell line HaCaT. We found that casuarinin suppressed TNF-α/IFN-γ-induced expression of TARC and MDC mRNA and protein in HaCaT cells. Casuarinin significantly inhibited TNF-α/IFN-γ-induced activation of NF-κB, STAT1, and p38 MAPK. Furthermore, we observed that p38 MAPK contributes to inhibition of TNF-α/IFN-γ-induced TARC and MDC production by blocking NF-κB and STAT1 activation in HaCaT cells. Taken together, these results suggest that casuarinin may exert anti-inflammatory responses by suppressing TNF-α/IFN-γ-induced expression of TARC and MDC via blockage of p38 MAPK activation and subsequent activation of NF-κB and STAT1. We propose that it could therefore be used as a therapeutic agent against inflammatory skin diseases. 相似文献
992.
Youn W. Han 《Journal of industrial microbiology & biotechnology》1989,4(6):447-451
Summary A levan-producing bacterium was isolated from soils and its characteristics for polysaccharide synthesis were studied. A series of enrichment and plating techniques enabled the isolation of a levan-producing bacterium from closely related contaminants. Cultural and physiological characteristics of the isolate identified the organism an a strain ofBacillus polymyxa. The organism produced about 40 g extracellular polysaccharide per liter of sucrose medium, which was about three times more yield than levan obtained from known levan producers. The highest amount of polysaccharide was on a 8% sucrose medium. Hydrolysis of the product showed that the polysaccharide consisted entirely ofd-fructose, and13C.n.m.r. spectra confirmed that the product was levan, a fructose polymer linked by B-(26) fructofuranosyl linkage. 相似文献
993.
Anti-oxidant constituents from Sedum takesimense 总被引:1,自引:0,他引:1
Thuong PT Kang HJ Na M Jin W Youn UJ Seong YH Song KS Min BS Bae K 《Phytochemistry》2007,68(19):2432-2438
As part of an ongoing search for antioxidants from medicinal plants, 14 phenolic constitutents were isolated from the Korean endemic species Sedum takesimense Nakai. Their structures were determined as 1-(4-hydroxyphenyl)-2-(3,5-dihydroxyphenyl)-2-hydroxyethanone (5), gossypetin-8-O-beta-d-xylopyranoside (10), and 2,6-di-O-galloylarbutin (13) on the basis of spectroscopic analyses (IR, UV, 1D and 2D NMR, HR-MS) and chemical degradation, together with 11 previously known phenolics. Two of those (10 and 13) exhibited strong scavenging activities against DPPH and superoxide radicals as well as significant inhibitory effects on lipid peroxidation (IC(50) 14.0 and 10.8 microM, respectively) and LDL oxidation induced by a metal ion Cu(2+) (IC(50) 5.7 and 3.3 microM, respectively). 相似文献
994.
995.
A fungal strain BCP, which parasitizes Botrytis cinerea gray mold pathogen, was isolated and identified as Acremonium strictum. BCP strain overgrew the colonies of B. cinerea and caused severe lysis of the host hyphae. Frequent penetration and hyphal growth of A. strictum BCP inside the mycelia of B. cinerea were observed under light microscopy. In addition, some morphological abnormalities such as granulation and vacuolation of the cytoplasm were observed in mycelia and spores of B. cinerea. In dual culture test, A. strictum BCP strongly inhibited the mycelial growth of several plant pathogenic fungi as well as B. cinerea. To our knowledge, this is the first report on mycoparasitism of Acremonium species on B. cinerea. 相似文献
996.
997.
V. P. Smirnov V. E. Fortov Yu. A. Bykov V. A. Ermolaev E. E. Son E. M. Bazelyan Yu. V. Skobarikhin E. V. Grabovski G. M. Oleinik A. O. Shishlov A. N. Gribov V. K. Grigor’yants Yu. A. Goryushin 《Plasma Physics Reports》2016,42(2):177-185
Conditions for the propagation in soil of current pulses with an amplitude of up to 85 kA and temporal characteristics typical of a lightning stroke are studied with the help of a specially designed mobile test complex on the basis of a 4-MJ capacitive energy storage with an output voltage of up to 2 MV. In contrast to the conventional opinion that the ionization processes in highly conductive soils are weakly pronounced, a dramatic reduction in the grounding resistance at a resistivity of about 100 Ω m and currents above 10 kA was observed. A time interval in which the grounding resistance is determined by the skin effect in soil is revealed. It is shown that the grounding resistance continues to decrease behind the front of the current pulse due to the continuous growth of spark channels in soil. Time variations in the grounding resistance cannot be related to the formation of a continuous ionization zone near the grounding electrodes and are explained only by the simultaneous growth of several long spark channels extending from the grounding device. 相似文献
998.
Wook-Dong Kim Yong-ho Lee Min-Hee Kim Sun-Young Jung Woo-Chan Son Seon-Joo Yoon Byung-Wan Lee 《PloS one》2012,7(12)
Aim
Glucagon is an essential regulator of hepatic glucose production (HGP), which provides an alternative therapeutic target for managing type 2 diabetes with glucagon antagonists. We studied the effect of a novel human monoclonal antibody against glucagon receptor (GCGR), NPB112, on glucose homeostasis in diet-induced obese (DIO) mice.Methods
The glucose-lowering efficacy and safety of NPB112 were investigated in DIO mice with human GCGR for 11 weeks, and a hyperinsulinemic-euglycemic clamp study was conducted to measure HGP.Results
Single intraperitoneal injection of NPB112 with 5 mg/kg effectively decreased blood glucose levels in DIO mice for 5 days. A significant reduction in blood glucose was observed in DIO mice treated with NPB112 at a dose ≥5 mg/kg for 6 weeks, and its glucose-lowering effect was dose-dependent. Long-term administration of NPB112 also caused a mild 29% elevation in glucagon level, which was returned to the normal range after discontinuation of treatment. The clamp study showed that DIO mice injected with NPB112 at 5 mg/kg were more insulin sensitive than control mice, indicating amelioration of insulin resistance by treatment with NPB112. DIO mice treated with NPB112 showed a significant improvement in the ability of insulin to suppress HGP, showing a 33% suppression (from 8.3 mg/kg/min to 5.6 mg/kg/min) compared to the 2% suppression (from 9.8 mg/kg/min to 9.6 mg/kg/min) in control mice. In addition, no hypoglycemia or adverse effect was observed during the treatment.Conclusions
A novel human monoclonal GCGR antibody, NPB112, effectively lowered the glucose level in diabetic animal models with mild and reversible hyperglucagonemia. Suppression of excess HGP with NPB112 may be a promising therapeutic modality for the treatment of type 2 diabetes. 相似文献999.
Genome sequence of benzo(a)pyrene-degrading bacterium Novosphingobium pentaromativorans US6-1 总被引:2,自引:0,他引:2
Novosphingobium pentaromativorans US6-1 showed a good ability to degrade high-molecular-weight polycyclic aromatic hydrocarbons. We report the draft genome sequence of strain US6-1, which contains a main chromosome (5,096,413 bp, G+C content of 63.1%) and two plasmids (188,476 and 60,085 bp). The majority of the aromatic-hydrocarbon-degrading genes are encoded in the larger plasmid. 相似文献
1000.
Dong-Kyu Kim Min-Hyun Park Dong-Yeop Chang Kyung Mi Eun Hyun-Woo Shin Ji-Hun Mo Eui-Cheol Shin Hong Ryul Jin Sue Shin Eun Youn Roh Doo Hee Han Dae Woo Kim 《PloS one》2014,9(10)