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991.
Kevin J. Filipski Angel Guzman-Perez Jianwei Bian Christian Perreault Gary E. Aspnes Mary T. Didiuk Robert L. Dow Richard F. Hank Christopher S. Jones Robert J. Maguire Meihua Tu Dongxiang Zeng Shenping Liu John D. Knafels John Litchfield Karen Atkinson David R. Derksen Francis Bourbonais Jeffrey A. Pfefferkorn 《Bioorganic & medicinal chemistry letters》2013,23(16):4571-4578
Glucokinase activators are a class of experimental agents under investigation as a therapy for Type 2 diabetes mellitus. An X-ray crystal structure of a modestly potent agent revealed the potential to substitute the common heterocyclic amide donor–acceptor motif for a pyridone moiety. We have successfully demonstrated that both pyridone and pyrimidone heterocycles can be used as a potent donor–acceptor substituent. Several sub-micromolar analogs that possess the desired partial activator profile were synthesized and characterized. Unfortunately, the most potent activators suffered from sub-optimal pharmacokinetic properties. Nonetheless, these donor–acceptor motifs may find utility in other glucokinase activator series or beyond. 相似文献
992.
Minhang Xin Jun Wen Feng Tang Chongxing Tu Han Shen Xinge Zhao 《Bioorganic & medicinal chemistry letters》2013,23(24):6777-6783
Hedgehog signaling pathway inhibitors are emerging as new therapeutic intervention against cancer. A novel series of N-(2-pyrimidinylamino) benzamide derivatives as hedgehog signaling pathway inhibitors were designed and synthesized. Most compounds presented significant inhibitory effect on hedgehog signaling pathway, among which 21 compounds exhibited more potent than vismodegib. Furthermore, compound 6a showed moderate pharmacokinetic properties in vivo, representing a promising lead compound for further exploration. 相似文献
993.
A novel,major, and validated QTL for the effective tiller number located on chromosome arm 1BL in bread wheat 总被引:2,自引:0,他引:2
Liu Jiajun Tang Huaping Qu Xiangru Liu Hang Li Cong Tu Yang Li Shuiqing Habib Ahsan Mu Yang Dai Shoufeng Deng Mei Jiang Qiantao Liu Yaxi Chen Guoyue Wang Jirui Chen Guangdeng Li Wei Jiang Yunfeng Wei Yuming Lan Xiujin Zheng Youliang Ma Jian 《Plant molecular biology》2020,104(1-2):173-185
Plant Molecular Biology - A novel and major QTL for the effective tiller number was identified on chromosomal arm 1BL and validated in two genetic backgrounds The effective tiller number (ETN)... 相似文献
994.
Gardiner Alastair T. Nguyen-Phan Tu C. Cogdell Richard J. 《Photosynthesis research》2020,145(2):83-96
Photosynthesis Research - All purple photosynthetic bacteria contain RC–LH1 ‘Core’ complexes. The structure of this complex from Rhodobacter sphaeroides, Rhodopseudomonas... 相似文献
995.
Ying-ping Huang Ali Haris Malik Zhi-ying Tu David Johnson Wei-Ming Li Xi Yuan 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):811-816
The swimming performance of juvenile rock carp (Procypris rabaudi, Tchang) subjected to repeated fatigue exercise was studied using a flume-type respirometer at 20°C. The critical swimming speed (Ucrit) and oxygen consumption rate (MO2) of juvenile rock carp were measured during two successive stepped velocity tests, following a 60 min rest interval. Ucrit of rock carp was giving a recovery ratio (Rr) of 92.64%, and exertion exercise decreases Ucrit. When MO2 was plotted as a linear function of U, the slope for trial 1 was 1.06 and 1.50 for trial 2, indicating a decreasing in swimming efficiency. The maximum metabolic rate (MMR) increased from 17.06 ± 1.14 mmol O2/(kg·hr) to 19.14 ± 1.23 mmol O2/(kg·hr), and the exercise post oxygen consumption rate (EPOC) increased from 9.00 to 9.65 mmol O2/kg. Repeated fatiguing exercise increased both the aerobic and anaerobic cost of reaching Ucrit, but anaerobic metabolism accounted for a larger proportion in the trial 2. The data investigation on the swimming performance and the physiological response to fatigue provide important design criteria for fishways. 相似文献
996.
Juribašić M Molčanov K Kojić-Prodić B Bellotto L Kralj M Zani F Tušek-Božić L 《Journal of inorganic biochemistry》2011,105(6):867-879
Three types of palladium(II) halide complexes of quinolinylaminophosphonates have been synthesized and studied. Diethyl and dibutyl [α-anilino-(quinolin-2-ylmethyl)]phosphonates (L1, L2) act as N,N-chelate ligands through the quinoline and aniline nitrogens giving complexes cis-[Pd(L1/L2)X2] (X═Cl, Br) (1-4). Their 3-substituted analogues [α-anilino-(quinolin-3-ylmethyl)]phosphonates (L3, L4) form dihalidopalladium complexes trans-[Pd(L3/L4)2X2] (5-8), with trans N-bonded ligand molecules only through the quinoline nitrogen. Dialkyl [α-(quinolin-3-ylamino)-N-benzyl]phosphonates (L5, L6) give tetrahalidodipalladium complexes [Pd2(L5/L6)3X4] (9-12), containing one bridging and two terminal ligand molecules. The bridging molecule is bonded to the both palladium atoms, one through the quinoline and the other through the aminoquinoline nitrogen, whereas terminal ligand molecules are coordinated each only to one palladium via the quinoline nitrogen. Each palladium ion is also bonded to two halide ions in a trans square-planar fashion. The new complexes were identified and characterized by elemental analyses and by IR, UV-visible, 1H, 13C and 31P nuclear magnetic resonance and ESI-mass spectroscopic studies. The crystal structures of complexes 1-4 and 6 were determined by X-ray structure analysis. The antitumor activity of complexes in vitro was investigated on several human tumor cell lines and the highest activity with cell growth inhibitory effects in the low micromolar range was observed for dipalladium complexes 11 and 12 derived from dibutyl ester L6. The antimicrobial properties in vitro of ligands and their complexes were studied using a wide spectrum of bacterial and fungal strains. No specific activity was noted. Only ligands L3 and L4 and tetrahalidodipalladium complexes 9 and 11 show poor activities against some Gram positive bacteria. 相似文献
997.
Three pathogens, Riemerella anatipestifer, Escherichia coli, and Salmonella enterica, are leading causes of bacterial fibrinous pericarditis and perihepatitis in ducks in China and worldwide. It is difficult to differentiate these pathogens when obtaining a diagnosis on clinical signs and pathological changes. The aim of this research was to develop a multiplex polymerase chain reaction (m-PCR) that could discriminate R. anatipestifer, E. coli, and S. enterica rapidly in field isolates, or detect the three bacteria in clinical samples from diseased ducks. We selected the DnaB helicase (dnaB) gene of R. anatipestifer, alkaline phosphatase (phoA) gene of E. coli and invasion protein (invA) gene of S. enterica as target genes. In optimized conditions, the limitation of detection was approximately 103 colony forming units (CFU) of each of these three bacterial pathogens per PCR reaction tube. The m-PCR method showed specific amplification of respective genes from R. anatipestifer, E. coli, and S. enterica. Using the m-PCR system, bacterial strains isolated from diseased ducks in our laboratory were categorized successfully, and the pathogens could also be detected in clinical samples from diseased ducks. Therefore, the m-PCR system could distinguish the three pathogens simultaneously, for identification, routine molecular diagnosis and epidemiology, in a single reaction. 相似文献
998.
Khursigara CM Lan G Neumann S Wu X Ravindran S Borgnia MJ Sourjik V Milne J Tu Y Subramaniam S 《The EMBO journal》2011,30(9):1719-1729
In chemotactic bacteria, transmembrane chemoreceptors, CheA and CheW form the core signalling complex of the chemotaxis sensory apparatus. These complexes are organized in extended arrays in the cytoplasmic membrane that allow bacteria to respond to changes in concentration of extracellular ligands via a cooperative, allosteric response that leads to substantial amplification of the signal induced by ligand binding. Here, we have combined cryo-electron tomographic studies of the 3D spatial architecture of chemoreceptor arrays in intact E. coli cells with computational modelling to develop a predictive model for the cooperativity and sensitivity of the chemotaxis response. The predictions were tested experimentally using fluorescence resonance energy transfer (FRET) microscopy. Our results demonstrate that changes in lateral packing densities of the partially ordered, spatially extended chemoreceptor arrays can modulate the bacterial chemotaxis response, and that information about the molecular organization of the arrays derived by cryo-electron tomography of intact cells can be translated into testable, predictive computational models of the chemotaxis response. 相似文献
999.
1000.