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251.
Dendritic cells and innate defense against tumor cells 总被引:1,自引:0,他引:1
Ullrich E Ménard C Flament C Terme M Mignot G Bonmort M Plumas J Chaperot L Chaput N Zitvogel L 《Cytokine & growth factor reviews》2008,19(1):79-92
Tumor growth results from a delicate balance between intrinsic dysregulation of oncogenes, tumor suppressor and stability genes counteracted by extrinsic defenses composed of immune cells shaping tumor immunogenicity. Although immune subversion might be the ultimate outcome of this process, a complex network of cellular interactions take place eventually leading to tumor specific cognate immune responses. The links between innate and cognate antitumor immunity eliciting protective T cell responses are instigated by cytokines, chemokines and damage associated molecular patterns. The intricate differentiation pathway whereby dendritic cells could undergo an efficient maturation program in the tumor microenvironment appears crucial. We will discuss the role of innate effectors and cancer therapies in the process of defense against tumor cells. 相似文献
252.
Soil cover, which is one of the most informative and integrative landscape factors, can be used for the analysis of landscape patterns. We studied the spatial autocorrelation (Moran's I) of raster format soil maps (1:10,000; 10 m pixel size) in 35 study areas representing all landscape regions in Estonia. The carbonate concentration of soils, volumetric soil moisture (%) and the depth of the groundwater table were taken into consideration in compiling a scale of contrast of 17 soil groups. We introduce a simple characteristic based on spatial correlograms: a half-value distance lag, hI = 0.5—a distance where Moran's I drops below 0.5. Spatial autocorrelation decreased very rapidly in the case of heights with a very heterogeneous landscape composition, showing low values of hI = 0.5 (<100 m in all 6 study areas). In uplands and depressions, the spatial autocorrelation also decreased relatively rapidly (hI = 0.5 < 200 m). In most of the plains, coastal lowlands, sea islands and inland paludified lowlands, the values of Moran's I did decrease slowly with increasing lag, being >200 m in all forest and bog areas with complex topographical conditions due to the variety of glacial landforms and peatlands. All of the eight FRAGSTATS landscape metrics studied demonstrated significant correlations with hI = 0.5, whereas five of them – Contrast Weighted Edge Density (CWED); Percentage of Like Adjacencies (PLADJ), Edge Density (ED), Patch Density (PD) and Mean Patch Area Distribution (AREA_MN) – had Spearman Rank Order Correlation values higher than 0.8. Landscapes with high ED, PD, and CWED values have a low autocorrelation: PD, ED, and CWED correlated negatively with hI = 0.5. PD, ED, and CWED decreased and PLADJ increased with the power-law relationship with increasing hI = 0.5. Spatial autocorrelation is lower in landscapes with complex structure and high contrast. The positive relationship with PLADJ indicates the same. Thus, spatial correlograms of potential landscape structure based on soil cover analysis can be used for the characterization of human-influenced landscape (land use) structure. 相似文献
253.
Dominik Lutter Peter Ugocsai Margot Grandl Evelyn Orso Fabian Theis Elmar W Lang Gerd Schmitz 《BMC bioinformatics》2008,9(1):100
Background
The analysis of high-throughput gene expression data sets derived from microarray experiments still is a field of extensive investigation. Although new approaches and algorithms are published continuously, mostly conventional methods like hierarchical clustering algorithms or variance analysis tools are used. Here we take a closer look at independent component analysis (ICA) which is already discussed widely as a new analysis approach. However, deep exploration of its applicability and relevance to concrete biological problems is still missing. In this study, we investigate the relevance of ICA in gaining new insights into well characterized regulatory mechanisms of M-CSF dependent macrophage differentiation. 相似文献254.
Sessions EH Yin Y Bannister TD Weiser A Griffin E Pocas J Cameron MD Ruiz C Lin L Schürer SC Schröter T LoGrasso P Feng Y 《Bioorganic & medicinal chemistry letters》2008,18(24):6390-6393
Inhibitors of Rho kinase have been developed based on two distinct scaffolds, benzimidazoles, and benzoxazoles. SAR studies and efforts to optimize the initial lead compounds are described. Novel selective inhibitors of ROCK-II with excellent potency in both enzyme and cell-based assays were obtained. These inhibitors possess good microsomal stability, low cytochrome P-450 inhibitions and good oral bioavailability. 相似文献
255.
Chen YT Bannister TD Weiser A Griffin E Lin L Ruiz C Cameron MD Schürer S Duckett D Schröter T LoGrasso P Feng Y 《Bioorganic & medicinal chemistry letters》2008,18(24):6406-6409
Inhibition of Rho kinase (ROCK) is an attractive strategy for the treatment of diseases such as hypertension, glaucoma, and cancer. Here we report chroman-3-amides as highly potent ROCK inhibitors with sufficient kinase selectivity, excellent cell activity, good microsomal stability, and desirable pharmacokinetic properties for study as potential therapeutic agents. 相似文献
256.
McGregor AP Pechmann M Schwager EE Feitosa NM Kruck S Aranda M Damen WG 《Current biology : CB》2008,18(20):1619-1623
The Wnt genes encode secreted glycoprotein ligands that regulate many developmental processes from axis formation to tissue regeneration [1]. In bilaterians, there are at least 12 subfamilies of Wnt genes [2]. Wnt3 and Wnt8 are required for somitogenesis in vertebrates [3-7] and are thought to be involved in posterior specification in deuterostomes in general [8]. Although TCF and beta-catenin have been implicated in the posterior patterning of some short-germ insects [9, 10], the specific Wnt ligands required for posterior specification in insects and other protostomes remained unknown. Here we investigated the function of Wnt8 in a chelicerate, the common house spider Achaearanea tepidariorum[11]. Knockdown of Wnt8 in Achaearanea via parental RNAi caused misregulation of Delta, hairy, twist, and caudal and resulted in failure to properly establish a posterior growth zone and truncation of the opisthosoma (abdomen). In embryos with the most severe phenotypes, the entire opisthosoma was missing. Our results suggest that in the spider, Wnt8 is required for posterior development through the specification and maintenance of growth-zone cells. Furthermore, we propose that Wnt8, caudal, and Delta/Notch may be parts of an ancient genetic regulatory network that could have been required for posterior specification in the last common ancestor of protostomes and deuterostomes. 相似文献
257.
Here we present a biochemical and molecular biology study of the enzyme pyruvate kinase (PYK) from the parasitic protozoa Leishmania donovani. The PYK gene was cloned, mutagenised and over expressed and its kinetic parameters determined. Like in other kinetoplastids, L. donovani PYK is allosterically stimulated by the effector fructose 2,6 biphosphate and not by fructose 1,6 biphosphate. When the putative effector binding site of L. donovani PYK was mutagenised, we obtained two mutants with extreme kinetic behavior: Lys453Leu, which retained a sigmoidal kinetics and was little affected by the effector; and His480Gln, which deployed a hyperbolic kinetics that was not changed by the addition of the effector. Molecular Dynamics (MD) studies revealed that the mutations not only altered the effector binding site of L. donovani PYK but also changed the folding of its domain C. 相似文献
258.
A new species of Late Cretaceous clawed lobster, Paraclytia valashtensis, is described. The discovery is a notable addition to the sparse decapod fossil record of Iran, and this is the first record
of the genus outside central Europe. The four previously known species of Paraclytia are from Germany and the Czech Republic, so this discovery represents a significant expansion of the palaeogeographic range
of the genus. 相似文献
259.
David A. Scott Kirsten J. Bell Cheryl T. Campbell Donald J. Cook Les A. Dakin David J. Del Valle Lisa Drew Thomas W. Gero Maureen M. Hattersley Charles A. Omer Boris Tyurin Xiaolan Zheng 《Bioorganic & medicinal chemistry letters》2009,19(3):701-705
The optimization of compounds from the 3-amido-4-anilinoquinolines series of CSF-1R kinase inhibitors is described. The series has excellent activity and kinase selectivity. Excellent physical properties and rodent PK profiles were achieved through the introduction of cyclic amines at the quinoline 6-position. Compounds with good activity in a mouse PD model measuring inhibition of pCSF-1R were identified. 相似文献
260.