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961.
DeNinno MP Masamune H Chenard LK DiRico KJ Eller C Etienne JB Tickner JE Kennedy SP Knight DR Kong J Oleynek JJ Tracey WR Hill RJ 《Bioorganic & medicinal chemistry letters》2006,16(9):2525-2527
Using a combination of parallel and directed synthesis, the discovery of a highly potent and selective series of adenosine A3 agonists was achieved. High aqueous solubility, required for the intended parenteral route of administration, was achieved by the presence of one or two basic amine functional groups. 相似文献
962.
Weterings JJ Khan S van der Heden GJ Drijfhout JW Melief CJ Overkleeft HS van der Burg SH Ossendorp F van der Marel GA Filippov DV 《Bioorganic & medicinal chemistry letters》2006,16(12):3258-3261
The preparation of three different 2-alkoxy-8-hydroxyadenylpeptide conjugates has been accomplished by solid-phase synthesis combined with 'on-resin' Cu(I) catalyzed Huisgen cycloaddition. The immunogenicity of the compounds has been evaluated in IL-12 production and antigen presentation assays. 相似文献
963.
Kuo PY Shie TL Chen YS Lai JT Yang DY 《Bioorganic & medicinal chemistry letters》2006,16(23):6024-6027
Two cyclopropanecarbonyl derivatives were independently found to be 15 and 14 times more potent than the corresponding isopropylcarbonyl analogues as inhibitors of 4-hydroxyphenylpyruvate dioxygenase and dihydroorotate dehydrogenase, respectively. A thorough examination of the co-crystal structures of available enzyme inhibitor complexes and the conformation of X-ray crystal structures of several synthesized cyclopropanecarbonyl derivatives revealed that this enhancement by one order of magnitude of inhibition potency exhibited by cyclopropanecarbonyl derivatives in both enzymes is probably caused by respective metal chelating and hydrogen bonding interactions at the ligand-receptor binding site. These specific interactions subsequently cause the cyclopropyl group of the molecules to adopt a fixed bisected conformation, which is unavailable for isopropylcarbonyl derivatives. 相似文献
964.
965.
966.
Oxidative stress plays an important role in the pathological processes of various neurodegenerative diseases. Ugonin K, a
flavonoid isolated from the rhizomes of Helminthostachys zeylanica, possesses potent antioxidant property. In this study, we investigate the neuroprotective effects of ugonin K on hydrogen
peroxide (H2O2)-induced apoptosis in SH-SY5Y cells. Incubation of SH-SY5Y cells with H2O2 for 24 h induced cell death measured with MTT assay. Hoechst 33258 staining confirmed that the reduced cell viability by
H2O2 was due to apoptosis. In addition, H2O2 increased the expression of 17-kDa cleaved fragment of caspase-3 which could be reversed by pretreatment with ugonin K. Pretreatment
with ugonin K attenuated H2O2-induced cell death in a dose-dependent manner. Neuroprotective effect of ugonin K was abolished by ERK and PI3K inhibitors.
Pretreatment with JNK kinase and p38 MAPK inhibitors had no effect on ugonin K-mediated protection against H2O2-induced apoptosis. Western blotting with anti-phospho-ERK1/2 and anti-phospho-Akt (pS473) antibodies showed that ugonin K
increased both ERK1/2 and Akt phosphorylation. These results suggest that ugonin K by activation of ERK1/2 and PI3K/Akt signal
pathways protects SH-SY5Y cells from H2O2-induced apoptosis. 相似文献
967.
Chi-Yu Huang Shou-Pin Hsieh Pei-An Kuo Wann-Neng Jane Jenn Tu Ya-Nan Wang Chun-Han Ko 《International biodeterioration & biodegradation》2009,63(8):998-1007
Biofilm formation in papermaking processes could inflict financial loss by interrupting paper machine operation and pose a potential health hazard. A mixed microbial culture obtained from paper machine slime and a Pseudomonas strain (identified as Pseudomonas putida HB45) which is tolerant to the alkyl dimethyl benzyl ammonium chloride (quaternary ammonium chloride, QAC) were used to investigate the interplay between disinfectants and glucose on bacterial growth and biofilm formation. QAC and 2,2-dibromo-3-nitrilopropionamide (DBNPA) were found to be effective at concentration lower than isothiazolone in both standardized Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. Crystal violet staining technique demonstrated that biofilm formation of P. putida HB45 and the mixed culture could be controlled by modest dosage of DBNPA and QAC; however, they could be barely eliminated due to high MBC to MIC ratios. In simulated papermaking processing water, glucose was shown to increase the average biofilm formation rates during stationary phase for both P. putida HB45 and the mixed culture under the presence of biocides. Complexity and population diversity of biofilm of the paper machine slime was observed by in-situ cryo-scanning electron microscopy. Confocal laser scanning microscopy (CSLM) was employed to show qualitative and partial quantitative biofilm formation under various circumstances. The results of this study could assist improving strategy for controlling biofilm formation in papermaking processes. 相似文献
968.
Songpo Guo Suresh K. Tipparaju Scott D. Pegan Baojie Wan Shunyan Mo Jimmy Orjala Andrew D. Mesecar Scott G. Franzblau Alan P. Kozikowski 《Bioorganic & medicinal chemistry》2009,17(20):7126-7130
Indolo[2,3-a]carbazole based inhibitors were synthesized from readily available indigo via a seven-step linear synthetic sequence with a moderate overall yield. The inhibitors were selectively and readily functionalized at the nitrogen on the indole portion of the carbazole unit. The synthesized analogs displayed moderate inhibitory activities toward Bacillus anthracis and Mycobacterium tuberculosis, indicating that indolo[2,3-a]carbazoles could serve as promising leads in the development of new drugs to combat anthrax and tuberculosis infections. 相似文献
969.
Li‐Yi Sun Dean‐Kuo Hsieh Tzai‐Chiu Yu Hsien‐Tai Chiu Sheng‐Fen Lu Geng‐Hong Luo Tom K. Kuo Oscar K. Lee Tzyy‐Wen Chiou 《Bioelectromagnetics》2009,30(4):251-260
Pulsed electromagnetic fields (PEMFs) have been used clinically to slow down osteoporosis and accelerate the healing of bone fractures for many years. The aim of this study is to investigate the effect of PEMFs on the proliferation and differentiation potential of human bone marrow mesenchymal stem cells (BMMSC). PEMF stimulus was administered to BMMSCs for 8 h per day during culture period. The PEMF applied consisted of 4.5 ms bursts repeating at 15 Hz, and each burst contained 20 pulses. Results showed that about 59% and 40% more viable BMMSC cells were obtained in the PEMF‐exposed cultures at 24 h after plating for the seeding density of 1000 and 3000 cells/cm2, respectively. Although, based on the kinetic analysis, the growth rates of BMMSC during the exponential growth phase were not significantly affected, 20–60% higher cell densities were achieved during the exponentially expanding stage. Many newly divided cells appeared from 12 to 16 h after the PEMF treatment as revealed by the cell cycle analysis. These results suggest that PEMF exposure could enhance the BMMSC cell proliferation during the exponential phase and it possibly resulted from the shortening of the lag phase. In addition, according to the cytochemical and immunofluorescence analysis performed, the PEMF‐exposed BMMSC showed multi‐lineage differentiation potential similar to the control group. Bioelectromagnetics 30:251–260, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
970.
Witold K. Subczynski Justyna Widomska Jimmy B. Feix 《Free radical biology & medicine》2009,46(6):707-718
The influence of a variety of microenvironmental factors on the inherent reactivity of membrane-located reagents is poorly understood. A goal of this review is to provide detailed profiles of membrane properties, including hydrophobicity, oxygen and nitric oxide solubility and diffusion rates, bilayer penetration of metal ions and metal-ion complexes, and membrane order and fluidity, that can be obtained with EPR spin-labeling methods. These properties can drastically vary with membrane composition, membrane depth, and membrane domain formation, influencing the fate of chemical reactions that occur in a lipid bilayer environment. 相似文献