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Samarjit Patnaik Dipanwita Basu Noel Southall Seameen Dehdashti Kanny K. Wan Wei Zheng Marc Ferrer Mercedes Taylor Daniel A. Engel Juan Jose Marugan 《Bioorganic & medicinal chemistry letters》2019,29(9):1113-1119
Nonstructural protein 1 (NS1) plays a crucial function in the replication, spread, and pathogenesis of influenza virus by inhibiting the host innate immune response. Here we report the discovery and optimization of novel pyrazolopyridine NS1 antagonists that can potently inhibit influenza A/PR/8/34 replication in MDCK cells, rescue MDCK cells from cytopathic effects of seasonal influenza A strains, reverse NS1-dependent inhibition of IFN-β gene expression, and suppress the slow growth phenotype in NS1-expressing yeast. These pyrazolopyridines will enable researchers to investigate NS1 function during infection and how antagonists can be utilized in the next generation of treatments for influenza infection. 相似文献
84.
Jing R Johnson R Seres A Kiss G Ambrose MJ Knox MR Ellis TH Flavell AJ 《Genetics》2007,177(4):2263-2275
Sequence diversity of 39 dispersed gene loci was analyzed in 48 diverse individuals representative of the genus Pisum. The different genes show large variation in diversity parameters, suggesting widely differing levels of selection and a high overall diversity level for the species. The data set yields a genetic diversity tree whose deep branches, involving wild samples, are preserved in a tree derived from a polymorphic retrotransposon insertions in an identical sample set. Thus, gene regions and intergenic "junk DNA" share a consistent picture for the genomic diversity of Pisum, despite low linkage disequilibrium in wild and landrace germplasm, which might be expected to allow independent evolution of these very different DNA classes. Additional lines of evidence indicate that recombination has shuffled gene haplotypes efficiently within Pisum, despite its high level of inbreeding and widespread geographic distribution. Trees derived from individual gene loci show marked differences from each other, and genetic distance values between sample pairs show high standard deviations. Sequence mosaic analysis of aligned sequences identifies nine loci showing evidence for intragenic recombination. Lastly, phylogenetic network analysis confirms the non-treelike structure of Pisum diversity and indicates the major germplasm classes involved. Overall, these data emphasize the artificiality of simple tree structures for representing genomic sequence variation within Pisum and emphasize the need for fine structure haplotype analysis to accurately define the genetic structure of the species. 相似文献
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Huang H Campbell SC Bedford DF Nelius T Veliceasa D Shroff EH Henkin J Schneider A Bouck N Volpert OV 《Molecular cancer research : MCR》2004,2(10):541-550
An expanding capillary network is critical for several pathologic conditions. In cancer, the decrease of antiangiogenic thrombospondin-1 (TSP1) often enables an angiogenic switch, which can be reversed with exogenous TSP1 or its peptide derivative ABT510. TSP1 acts by inducing endothelial cell apoptosis via signaling cascade initiated at CD36, a TSP1 antiangiogenic receptor. Here, we show that the ligands of nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma), 15-deoxy-delta(12,14)-prostaglandin J2, troglitazone, and rosiglitazone increased PPARgamma and CD36 expression in endothelial cells and improved the efficacy of TSP1 and ABT510 in a CD36-dependent manner. The ABT510 and PPARgamma ligands cooperatively blocked angiogenic endothelial functions in vitro and neovascularization in vivo. In tumor xenografts, 15-deoxy-delta(12,14)-prostaglandin J2 and troglitazone synergistically improved antiangiogenic and antitumor effects of ABT510. Our data provide one mechanism for the in vivo angioinhibitory effect of PPARgamma ligands and show fine-tuning of the antiangiogenic efficacy via targeted up-regulation of the endothelial receptor. 相似文献
87.
A microarray-based high throughput molecular marker genotyping method: the tagged microarray marker (TAM) approach 总被引:6,自引:0,他引:6
Flavell AJ Bolshakov VN Booth A Jing R Russell J Ellis TH Isaac P 《Nucleic acids research》2003,31(19):e115
A microarray-based method has been developed for scoring thousands of DNAs for a co-dominant molecular marker on a glass slide. The approach was developed to detect insertional polymorphism of transposons and works well with single nucleotide polymorphism (SNP) markers. Biotin- terminated allele-specific PCR products are spotted unpurified onto streptavidin-coated glass slides and visualised by hybridisation of fluorescent detector oligonucleotides to tags attached to the allele- specific PCR primers. Two tagged primer oligonucleotides are used per locus and each tag is detected by hybridisation to a concatameric DNA probe labelled with multiple fluorochromes. 相似文献
88.
Head development in the onychophoran Euperipatoides kanangrensis with particular reference to the central nervous system 总被引:2,自引:0,他引:2
The neuroectoderm of the Euperipatoides kanangrensis embryo becomes distinguishable during germ band formation when the antennal segment is evident externally. During later stages of development, the neuroectoderm proliferates extensively and, at the anterior part of the head, newly-formed neuron precursor cells occupy most of the volume. The antenna forms from the dorsolateral side of the anterior somite. The antenna has no neuroectoderm of its own at the onset of its formation, but instead, neurons migrate out to the appendage from the nearby region of the developing brain. When the antennal tract is formed it is positioned horizontally in the brain, in line with the antennal commissure. Only later, and coincidentally with the anterior repositioning of the antenna, is the tract's distal part bent anteriorly and positioned laterally. The eye starts to develop posteriorly to the antenna and the antennal commissure. This suggests that the segment(s) associated with the onychophoran eye and antenna are not serially homologous with segments carrying equivalent structures within the Euarthropoda. Evidence is presented to further support the presence of a terminal mouth in the ground plan of the Onychophora and, hence, an acron may not exist in the arthropod clade. 相似文献
89.
Iron porphyrin treatment extends survival in a transgenic animal model of amyotrophic lateral sclerosis 总被引:2,自引:0,他引:2
Wu AS Kiaei M Aguirre N Crow JP Calingasan NY Browne SE Beal MF 《Journal of neurochemistry》2003,85(1):142-150
Oxidative damage, produced by mutant Cu/Zn superoxide dismutase (SOD1), may play a role in the pathogenesis of amyotrophic lateral sclerosis (ALS), a devastating motor neuron degenerative disease. A novel approach to antioxidant therapy is the use of metalloporphyrins that catalytically scavenge a wide range of reactive oxygen and reactive nitrogen species. In this study, we examined the therapeutic potential of iron porphyrin (FeTCPP) in the G93A mutant SOD1 transgenic mouse model of ALS. We found that intraperitoneal injection of FeTCPP significantly improved motor function and extended survival in G93A mice. Similar results were seen with a second group of mice wherein treatment with FeTCPP was initiated at the onset of hindlimb weakness-roughly equivalent to the time at which treatment would begin in human patients. FeTCPP-treated mice also showed a significant reduction in levels of malondialdehyde (a marker of lipid peroxidation), in total content of protein carbonyls (a marker of protein oxidation), and increased neuronal survival in the spinal cord. These results therefore provide further evidence of oxidative damage in a mouse model of ALS, and suggest that FeTCPP could be beneficial for the treatment of ALS patients. 相似文献
90.
Noel S Herman A Johnson GA Gray CA Stewart MD Bazer FW Gertler A Spencer TE 《Biology of reproduction》2003,68(3):772-780
A hormonal servomechanism has been proposed to regulate differentiation and function of the endometrial glandular epithelium (GE) in the ovine uterus during pregnancy. This mechanism involves sequential actions of estrogen, progesterone, ovine interferon tau (IFNtau), placental lactogen (oPL), and placental growth hormone (oGH). The biological actions of oPL in vitro are mediated by homodimerization of the prolactin receptor (oPRLR) and heterodimerization of the oPRLR and oGH receptor. The objectives of the study were to determine the effects of intrauterine oPL, oGH, and their combination on endometrial histoarchitecture and gene expression and to localize and characterize binding sites for oPL in the ovine uterus in vivo using an in situ ligand binding assay. Intrauterine infusion of oPL and/or oGH following IFNtau into ovariectomized ewes treated with progesterone daily differentially affected endometrial gland number and expression of uterine milk proteins and osteopontin. However, neither hormone affected PRLR, insulin-like growth factor (IGF)-I, or IGF-II mRNA levels in the endometrium. A chimeric protein of placental secretory alkaline phosphatase (SEAP) and oPL was used to identify and characterize binding sites for oPL in frozen sections of interplacentomal endometrium from pregnant ewes. Specific binding of SEAP-oPL was detected in the endometrial GE on Days 30, 60, 90, and 120 of pregnancy. In Day 90 endometrium, SEAP-oPL binding to the endometrial GE was displaced completely by oPL and prolactin (oPRL) but only partially by oGH. Binding experiments using the extracellular domain of the oPRLR also showed that iodinated oPL binding sites could be competed for by oPRL and oPL but not by oGH. Collectively, results indicate that oPL binds to receptors in the endometrial glands and that oPRL is more effective than oGH in competing for these binding sites. Thus, effects of oPL on the endometrial glands may be mediated by receptors for oPRL and oGH. 相似文献