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81.
Dr. Hana Prokopcová Dr. Doris Dallinger Prof. Dr. Georg Uray Hung Yi Kristal Kaan Dr. Venkatasubramanian Ulaganathan Prof. Dr. Frank Kozielski Dr. Christian Laggner Prof. Dr. C. Oliver Kappe 《ChemMedChem》2010,5(10):1760-1769
Dihydropyrimidine‐based compounds belong to the first discovered inhibitors of the human mitotic kinesin Eg5. Although they are used by many research groups as model compounds for chemical genetics, considerably less emphasis has been placed on the improvement of this type of inhibitor, with the exception of two recent studies. Dihydropyrimidines can be divided into class I (analogues that bind in the S configuration) and class II type inhibitors, which bind in the R configuration. Herein we report the synthesis and optimization of novel class II type dihydropyrimidines using a combination of in vitro and docking techniques. 相似文献
82.
The role of platform as an information mediator has been becoming more vital by satisfying buyers’ needs for a reasonable purchase and sellers’ need for more exposure to buyers within the copious information flood. For the platform service provider, increasing the network externality is important to induce both sides while platforms can cause sellers to invest more and create severe competition among sellers, which take a toll on sellers’ surplus. Therefore, this study investigates whether platforms yield benefits for sellers as the platform matures, securing the network externality. Thus, this study divides the seller side industry into 3 periods based on the level of platform maturation. The efficiency in each period is measured using stochastic frontier analysis and efficiencies of each period are compared using meta-frontier analysis. The results show the overall industry efficiency improves with securing the network externality as the platform matures. However, if the individual firm is resistant to innovation, the firm’s efficiency might not be far behind compared to the firm which led the innovation. 相似文献
83.
Mary C. Hames Hana McFeeters W. Blake Holloway Christopher B. Stanley Volker S. Urban Robert L. McFeeters 《International journal of molecular sciences》2013,14(11):22741-22752
Bacterial Pth1 is essential for viability. Pth1 cleaves the ester bond between the peptide and nucleotide of peptidyl-tRNA generated from aborted translation, expression of mini-genes, and short ORFs. We have determined the shape of the Pth1:peptidyl-tRNA complex using small angle neutron scattering. Binding of piperonylpiperazine, a small molecule constituent of a combinatorial synthetic library common to most compounds with inhibitory activity, was mapped to Pth1 via NMR spectroscopy. We also report computational docking results, modeling piperonylpiperazine binding based on chemical shift perturbation mapping. Overall these studies promote Pth1 as a novel antibiotic target, contribute to understanding how Pth1 interacts with its substrate, advance the current model for cleavage, and demonstrate feasibility of small molecule inhibition. 相似文献
84.
Hyeonji Kim Hana Kim Ashik Mosaddik Rajendra Gyawali Kwang Seok Ahn Somi Kim Cho 《Food chemistry》2012
The underlying mechanisms of the anticancer activity of the ethanolic extract of mango peel (EEMP) and its constituents were investigated. EEMP induced death of human cervical carcinoma HeLa cells through apoptosis, as evidenced by the increased cell population in the sub-G1 phase and the appearance of fragmented nuclei. Treatment of the cells with EEMP also downregulated anti-apoptotic Bcl-2 expression, resulting in the proteolytic activation of caspase-3, 7, 8, and 9 and the degradation of poly (ADP-ribose) polymerase (PARP) protein. The major components of mango peel were identified by liquid chromatography–electrospray ionisation tandem mass spectrometry and gas chromatography–mass spectrometry. Our data suggest that EEMP is an excellent source of quercetin 3-O-galactoside, mangiferin gallate, isomangiferin gallate, quercetin-3-O-arabinopyranoside, and mangiferin along with unsaturated fatty acids oleic acid, linoleic acid, and ethyl linoleate, which may help to prevent cervical cancer and may be a useful agent for the treatment of some other malignancies. 相似文献
85.
Renáta Vadkertiová Hana Dudášová Eva Stratilová Marta Balaščáková 《Yeast (Chichester, England)》2019,36(10):617-631
Yeasts are common constituents of different types of soil. Their diversity depends on the season, the type and depth of the soil, the plant species, and the locality. In this study, diversity of yeasts isolated from the soil adjacent to five fruit trees (apple, appricot, peach, pear, and plum) in two localities (in Slovakia) in four sampling periods was examined. Our results demonstrated differences in the species richness and evenness among the yeast populations, which inhabited the soil beneath individual fruit tree species in both localities. Altogether, 32 ascomycetous and 27 basidiomycetous yeast species were discovered. The highest species richness was found in the soil adjacent to the apricot trees. Galactomyces candidum, Metschnikowia pulcherrima, Hanseniaspora uvarum, Schwanniomyces capriottii, and Tausonia pullulans, as well as the genus Apiotrichum, were present in soil samples in all samplings. Two species of the genus Holtermanniella (H. festucosa and H. takashimae) were exclusively isolated during Sampling IV in April. Cyberlindnera spp., Clavispora reshetovae, S. capriottii, and Trichosporon asahii were found only in one of two localities. Ascomycetous yeasts were present more frequently than their basidiomycetous counterparts in the three samplings (one in June and two in October); they formed from 65.6% to 70.8% of the total yeast population, whereas basidiomycetous yeasts prevailed in the April sampling (61.2%). 相似文献
86.
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88.
We have investigated the electrocaloric (EC) properties of the ceramic 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3. A variety of samples with different median grain sizes, i.e., 1.0, 2.2 and 4.0?μm, and relative densities of about 96% were prepared using atmospheric sintering at 1200oC for 2, 8 and 16?h. The ceramic material with a median grain size of 2.2?μm exhibited the highest value for the EC temperature change, i.e., 1.27?K at 60?kV?cm?1, measured with a high-resolution calorimeter. This value is 25 and 19% higher than the value for the ceramics with the finer and the coarser grains, respectively. 相似文献
89.
Magda Doležalová Rahula Janiš Hana Svobodová Věra Kašpárková Petr Humpolíček Jiří Krejčí 《European Journal of Lipid Science and Technology》2010,112(10):1106-1114
Antimicrobial activity of monoacylglycerols (MAG) with odd number of carbons prepared from undecanoic (MAG C11:0) and undecenoic (MAG C11:1) was investigated. Data showed that both studied substances successfully inhibited Gram‐positive cocci (Staphylococcus aureus) and spore‐forming rods (Bacillus cereus). Gram‐negative bacteria were highly resistant against MAG C11:0 and showed considerable tolerance against MAG C11:1. Minimum inhibitory concentration (MIC) of MAG C11:1 was possible to determine for Escherichia coli only. Complete inhibition of three fungi genera (Alternaria, Cladosporium, Trichothecium) was achieved using MAG C11:1 with a concentration higher than 750 µg/mL. The growth of Aspergillus niger, Mucor racemosus, Phoma, Scopulariopsis, Trichoderma was significantly reduced. Generally, MAG C11:1 was more efficient than MAG C11:0 against all tested microorganisms. Due to a rich production of degradation enzymes, some fungi species surprisingly adapted their metabolism during growth and were even able to utilise tested MAG as a source of carbon. Practical applications: MAG composed of fatty acids with odd number of carbons in molecule are a promising group of substances applicable in food industry and cosmetics. They represent materials with broad spectrum of antimicrobial activity, especially against Gram‐positive bacteria. More efficient MAG C11:1 with a double bond in molecule can be recommended for reduction of S. aureus that cause food enterotoxicosis. 相似文献