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The development of selective protein kinase inhibitors has become an important area of drug discovery for the treatment of different diseases. We report the synthesis and characterization of a series of novel quinazoline derivatives against three therapeutically important and pharmacologically related kinases: 1) epidermal growth factor receptor (EGFR; wild type and mutant) in the field of cancer, 2) receptor-interacting caspase-like apoptosis-regulatory kinase (RICK) in the field of inflammation, and 3) pUL97 of human cytomegalovirus (HCMV). For reference purpose we have synthesized the four clinically relevant quinazolines, including the lead compounds, which we previously identified for RICK and pUL97. A total of 52 quinazoline derivatives were synthesized and tested on the basis of these leads to specifically target the hydrophobic pocket of the ATP-binding site. Selected compounds were tested on wild-type and mutant forms of EGFR, RICK, and pUL97 kinases; their logP and logS values for assessing suitability as drugs were calculated and hit or lead compounds identified.  相似文献   
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Wheat vernalization requirement is mainly controlled by the VRN1, VRN2, VRN3, and VRN4 genes. The first three have been cloned and have homoeologs in all three genomes. VRN4 has been found only in the D genome (VRN-D4) and has not been cloned. We constructed a high-density genetic map of the VRN-D4 region and mapped VRN-D4 within a 0.09 cM interval in the centromeric region of chromosome 5D. Using telocentric 5D chromosomes generated from the VRN-D4 donor Triple Dirk F, we determined that VRN-D4 is located on the short arm. The VRN-D4 candidate region is colinear with a 2.24 Mb region on Brachypodium distachyon chromosome 4, which includes 127 predicted genes. Ten of these genes have predicted roles in development but we detected no functional polymorphisms associated to VRN-D4. Two recombination events separated VRN-D4 from TaVIL-D1, the wheat homolog of Arabidopsis vernalization gene VIL1, confirming that this gene is not a candidate for VRN-D4. We detected significant interactions between VRN-D4 and other four genes controlling vernalization requirement (Vrn-A1, Vrn-B1, Vrn-D1, and Vrn-B3), which confirmed that VRN-D4 is part of the vernalization pathway and that it is either upstream or is part of the regulatory feedback loop involving VRN1, VRN2 and VRN3 genes. The precise mapping of VRN-D4 and the characterization of its interactions with other vernalization genes provide valuable information for the utilization of VRN-D4 in wheat improvement and for our current efforts to clone this vernalization gene.  相似文献   
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The Ph1 locus in hexaploid wheat (Triticum aestivum L.) enforces diploid-like behavior in the first metaphase of meiosis. To test the hypothesis that this chromosome pairing control is exercised by affecting the degree of chromatin condensation, the dispersion of rye chromatin in interphase nuclei in somatic tissues of wheat-rye chromosome translocations 1RS.1BL, 2RS.2BL, 2BS.2RL, 3RS.3DL and 5RS.5BL was compared in Ph1 and ph1b isogenic backgrounds. No significant differences in rye chromatin condensation that could be attributed to the Ph1 locus were detected. Regardless of the Ph1 status, each rye chromosome arm tested conformed to the general Rabl's orientation and occupied portions of the nuclei proportional to their length. Earlier observations that indicated the involvement of Ph1 locus in rye chromatin condensation in wheat could have been due either to specific loci on the studied 5RL rye arm that control the chromosome condensation process or to damage to the genetic system controlling chromatin condensation in the existing ph1b stocks of wheat. That damage might have been caused by homoeologous recombination and uneven disjunction of chromosomes from multivalents.  相似文献   
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Mate choice lies close to differential reproduction, the engine of evolution. Patterns of mate choice consequently have power to direct the course of evolution. Here we provide evidence suggesting one pattern of human mate choice—the tendency for mates to be similar in overall desirability—caused the evolution of a structure of correlations that we call the d factor. We use agent-based models to demonstrate that assortative mating causes the evolution of a positive manifold of desirability, d, such that an individual who is desirable as a mate along any one dimension tends to be desirable across all other dimensions. Further, we use a large cross-cultural sample with n = 14,478 from 45 countries around the world to show that this d-factor emerges in human samples, is a cross-cultural universal, and is patterned in a way consistent with an evolutionary history of assortative mating. Our results suggest that assortative mating can explain the evolution of a broad structure of human trait covariation.  相似文献   
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Herein we describe a new rhynchocephalian taxon from the Middle Jurassic of Patagonia, Argentina, representing the first Jurassic record of the group in South America. The new taxon, consisting of a complete dentary, is ascribed to Sphenodontia based on the presence of a deep and wide Meckelian groove, long posterior process, well‐developed coronoid process, and acrodont teeth showing dental regionalization including successional, alternate hatchling, and additional series. This allocation is reinforced by a phylogenetic analysis that places the new taxon in a basal position within a clade of sphenodontians that excludes Diphydontosaurus and Planocephalosaurus. Additionally, the new taxon clusters within a Gondwanan clade with the Indian Godavarisaurus from the Jurassic Kota Formation, sharing the presence of recurved and relatively large posterior successional teeth that are ribbed and bear a peculiar anterolingual groove. This sister‐group relationship is intriguing from a palaeobiogeographical viewpoint, as it suggests some degree of endemism during the initial stages of the breakup of Pangaea. We also discuss the ontogenetic stage of the new taxon and provide insights on the evolution of successional dentition in rhynchocephalians. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 342–360.  相似文献   
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A specific surface plasmon resonance imaging (SPRI) array biosensor for the determination of the enzymatically active cathepsin G (CatG) has been developed. For this purpose, a specific interaction between an inhibitor immobilized onto a chip surface and CatG in an analyzed solution was used. The MARS-115 CatG peptidyl inhibitor containing the 1-aminoalkylphosphonate diaryl ester moiety at the C terminus and N-succinamide with a free carboxylic function was synthesized and covalently immobilized onto the gold chip surface via the thiol group (cysteamine). Atomic force microscopy was used for the observation of surface changes during the subsequent steps of chip manufacture. Optimal detection conditions were chosen. High specificity of synthesized inhibitor to CatG was proved. The precision, as well as the accuracy, was found to be well suited to enzyme determination. The sensor application for the determination of CatG in white blood cells and saliva was shown for potential diagnosis of leukemia and oral cavity diseases during the early stages of those pathological states.  相似文献   
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