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991.
HTS screening identified 1 with micromolar inhibitory activity against PDK1. Optimization of 1 afforded 4i (BX-517) which has single-digit nanomolar activity against PDK1 and excellent selectivity against PKA.  相似文献   
992.
Lignins isolated from cotton stalks, jute stick and dhaincha by acidolytic dioxane were characterized using alkaline nitrobenzene oxidation, elemental analysis, methoxyl analysis and molecular weight analysis and UV, IR (1)H NMR spectroscopy. The C(9) formulas for cotton stalks, jute stick and dhaincha (Sesbania aculeata) lignin were C(9)H(9.36)O(4.50)(OCH(3))(1.23), C(9)H(9.02)O(4.57)(OCH(3))(1.35) and C(9)H(8.88)O(4.65)(OCH(3))(1.50), respectively. All three lignins were of the guaiacyl-syringyl type. Cotton stalks lignin contained more p-hydroxy phenyl unit than dhaincha and jute stick lignins as observed by alkaline nitrobenzene oxidation products. The beta-O-4 units in these nonwood lignins had predominately erythro stereochemistry type.  相似文献   
993.
Based on the lead compound BX-517, a series of C-4' substituted indolinones have been synthesized and evaluated for PDK1 inhibition. Modification at C-4' of the pyrrole afforded potent compounds (7b and 7d) with improved solubility and ADME properties. In this letter, we describe the synthesis, selectivity profile, and pharmacokinetic data of selected compounds.  相似文献   
994.
Larvae and juveniles of the roughskin sculpin Trachidermus fasciatus were collected during four cruises in March and April 2001 to study the distribution and diet of the fish in the Chikugo estuary in the northern Ariake Bay, Japan. Sampling was conducted at seven stations covering an area approximately 30 km in length along the estuary, with salinity ranging from nearly 0 to about 30 PSU. Gut contents were analyzed by separating, identifying, and counting the prey organisms. Plankton samples were collected during each cruise to study the numerical composition and abundance of copepods in ambient water. A total of 1790 larvae and juveniles of T. fasciatus were collected; they were distributed in the five uppermost stations, covering approximately 20 km and ranging in salinity from 0.4 to 27.4 PSU. The fish fed almost exclusively on a single calanoid copepod species, Sinocalanus sinensis, which was numerically the most abundant in the ambient water at the upper part of the Chikugo River. At the lower part of the river, the fish positively selected S. sinensis while negatively selecting other species. T. fasciatus larvae experienced a high proportion of empty guts and low feeding intensity at around 9.0 mm body length, which appears to be associated with commencement of exogenous feeding. The proportion of empty guts reduced sharply at subsequent stages and was accompanied by an increase in feeding intensity. The oligohaline and mesohaline areas are important nursery grounds, and S. sinensis is an important prey copepod species for the larval and juvenile T. fasciatus in the Chikugo estuary.  相似文献   
995.

Background  

Polymorphonuclear neutrophils (PMN) constitute an essential cellular component of innate host defense against microbial invasion and exhibit a wide array of responses both to particulate and soluble stimuli. As the cells recruited earliest during acute inflammation, PMN respond rapidly and release a variety of potent cytotoxic agents within minutes of exposure to microbes or their products. PMN rely on the redistribution of functionally important proteins, from intracellular compartments to the plasma membrane and phagosome, as the means by which to respond quickly. To determine the range of membrane proteins available for rapid recruitment during PMN activation, we analyzed the proteins in subcellular fractions enriched for plasma membrane and secretory vesicles recovered from the light membrane fraction of resting PMN after Percoll gradient centrifugation and free-flow electrophoresis purification using mass spectrometry-based proteomics methods.  相似文献   
996.
Proteomic analysis offers a new approach to identify a broad spectrum of genes that are expressed in living systems. We applied a proteomic approach to study changes in wheat grain in response to drought, a major environmental parameter adversely affecting development and crop yield. Three wheat genotypes differing in genetic background were cultivated in field under well-watered and drought conditions by following a randomized complete block design with four replications. The overall effect of drought was highly significant as determined by grain yield and total dry matter. About 650 spots were reproducibly detected and analyzed on 2-DE gels. Of these, 121 proteins showed significant change under drought condition in at least one of the genotypes. Mass spectrometry analysis using MALDI-TOF/TOF led to the identification of 57 proteins. Two-thirds of identified proteins were thioredoxin (Trx) targets, in accordance with the link between drought and oxidative stress. Further, because of contrasting changes in the tolerant and susceptible genotypes studied, several proteins emerge as key participants in the drought response. In addition to providing new information on the response to water deprivation, the present study offers opportunities to pursue the breeding of wheat with enhanced drought tolerance using identified candidate genetic markers. The 2-DE database of wheat seed proteins is available for public access at http://www.proteome.ir.  相似文献   
997.
There are almost 1,300 entries for higher eukaryotes in the Nuclear Protein Database. The proteins' subcellular distribution patterns within interphase nuclei can be complex, ranging from diffuse to punctate or microspeckled, yet they all work together in a coordinated and controlled manner within the three-dimensional confines of the nuclear volume. In this review we describe recent advances in the use of quantitative methods to understand nuclear spatial organisation and discuss some of the practical applications resulting from this work.  相似文献   
998.
To better understand the mechanism of vanadium reduction in ascidians, we examined the reduction of vanadium(V) to vanadium(IV) by NADPH and the reduction of vanadium(IV) to vanadium(III) by L-cysteine methyl ester (CysME). UV-vis and electron paramagnetic resonance spectroscopic studies indicated that in the presence of several biologically relevant ligands vanadium(V) and vanadium(IV) were reduced by NADPH and CysME, respectively. Specifically, NADPH directly reduced vanadium(V) to vanadium(IV) with the assistance of ligands that have a formation constant with vanadium(IV) of greater than 7. Also, glycylhistidine and glycylaspartic acid were found to assist the reduction of vanadium(IV) to vanadium(III) by CysME.  相似文献   
999.
The transport of cargo proteins to specific subcellular destinations is crucial for the different secretory and endocytic traffic pathways.One of the most impor...  相似文献   
1000.
Men have a statistically higher risk of metabolic and cardiovascular disease than premenopausal women, but the mechanisms mediating these differences are elusive. Chronic inflammation during obesity contributes to disease risk and is significantly more robust in males. Prior work demonstrated that compared with obese males, obese females have reduced proinflammatory adipose tissue macrophages (ATMs). Given the paucity of data on how sex hormones contribute to macrophage responses in obesity, we sought to understand the role of sex hormones in promoting obesity-induced myeloid inflammation. We used gonadectomy, estrogen receptor–deficient alpha chimeras, and androgen-insensitive mice to model sex hormone deficiency. These models were evaluated in diet-induced obesity conditions (high-fat diet [HFD]) and in vitro myeloid assays. We found that ovariectomy increased weight gain and adiposity. Ovariectomized females had increased ATMs and bone marrow myeloid colonies compared with sham-gonadectomized females. In addition, castrated males exposed to HFD had improved glucose tolerance, insulin sensitivity, and adiposity with fewer Ly6chi monocytes and bone marrow myeloid colonies compared with sham-gonadectomized males, although local adipose inflammation was enhanced. Similar findings were observed in androgen-insensitive mice; however, these mice had fewer CD11c+ ATMs, implying a developmental role for androgens in myelopoiesis and adipose inflammation. We concluded that gonadectomy results in convergence of metabolic and inflammatory responses to HFD between the sexes, and that myeloid estrogen receptor alpha contributes minimally to diet-induced inflammatory responses, whereas loss of androgen-receptor signaling improves metabolic and inflammatory outcomes. These studies demonstrate that sex hormones play a critical role in sex differences in obesity, metabolic dysfunction, and myeloid inflammation.  相似文献   
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