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排序方式: 共有542条查询结果,搜索用时 15 毫秒
1.
Cheon H Rho YH Choi SJ Lee YH Song GG Sohn J Won NH Ji JD 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(2):1092-1100
In inflamed joints of rheumatoid arthritis, PGE(2) is highly expressed, and IL-10 and IL-6 are also abundant. PGE(2) is a well-known activator of the cAMP signaling pathway, and there is functional cross-talk between cAMP signaling and the Jak-STAT signaling pathway. In this study, we evaluated the modulating effect of PGE(2) on STAT signaling and its biological function induced by IL-10 and IL-6, and elucidated its mechanism in THP-1 cells. STAT phosphorylation was determined by Western blot, and gene expression was analyzed using real-time PCR. Pretreatment with PGE(2) significantly augmented IL-10-induced STAT3 and STAT1 phosphorylation, as well as suppressors of cytokine signaling 3 (SOCS3) and IL-1R antagonist gene expression. In contrast, PGE(2) suppressed IL-6-induced phosphorylation of STAT3 and STAT1. These PGE(2)-induced modulating effects were largely reversed by actinomycin D. Pretreatment with dibutyryl cAMP augmented IL-10-induced, but did not change IL-6-induced STAT3 phosphorylation. Misoprostol, an EP2/3/4 agonist, and butaprost, an EP2 agonist, augmented IL-10-induced STAT3 phosphorylation and SOCS3 gene expression, but sulprostone, an EP1/3 agonist, had no effect. H89, a protein kinase A inhibitor, and LY294002, a PI3K inhibitor, diminished PGE(2)-mediated augmentation of IL-10-induced STAT3 phosphorylation. In this study, we found that PGE(2) selectively regulates cytokine signaling via increased intracellular cAMP levels and de novo gene expression, and these modulating effects may be mediated through EP2 or EP4 receptors. PGE(2) may modulate immune responses by alteration of cytokine signaling in THP-1 cells. 相似文献
2.
Man Il Kim Jee Yeon Baek Min Jee Kim Heon Cheon Jeong Ki-Gyoung Kim Chang Hwan Bae Yeon Soo Han Byung Rae Jin Iksoo Kim 《Molecules and cells》2009,28(4):347-363
The 15,389-bp long complete mitogenome of the endangered red-spotted apollo butterfly, Parnassius bremeri (Lepidoptera: Papilionidae) was determined in this study. The start codon for the COI gene in insects has been extensively discussed, and has long remained a matter of some controversy. Herein, we propose that the CGA (arginine) sequence functions as the start codon for the COI gene in lepidopteran insects, on the basis of complete mitogenome sequences of lepidopteran insects, including P. bremeri, as well as additional sequences of the COI start region from a diverse taxonomic range of lepidopteran species (a total of 53 species from 15 families). In our extensive search for a tRNA-like structure in the A+T-rich region, one tRNATrp-like sequence and one tRNALeu (UUR)-like sequence were detected in the P. bremeri A+T-rich region, and one or more tRNA-like structures were detected in the A+T-rich region of the majority of other sequenced lepidopteran insects, thereby indicating that such features occur frequently in the lepidopteran mitogenomes. Phylogenetic analysis using the concatenated 13 amino acid sequences and nucleotide sequences of PCGs of the four macrolepidopteran superfamilies together with the Tortricoidea and Pyraloidea resulted in the successful recovery of a monophyly of Papilionoidea and a monophyly of Bombycoidea. However, the Geometroidea were unexpectedly identified as a sister group of the Bombycoidea, rather than the Papilionoidea. 相似文献
3.
The purpose of this investigation was to characterize the in vitro stability and in vivo disposition of paclitaxel in rats after solubilization of paclitaxel into hydrotropic polymeric micelles. The amphiphilic block copolymers consisted of a micellar shell-forming poly(ethylene glycol) (PEG) block and a core-forming poly(2-(4-vinylbenzyloxy)-N,N-diethylnicotinamide) (P(VBODENA)) block. N,N-Diethylnicotinamide (DENA) in the micellar inner core resulted in effective paclitaxel solubilization and stabilization. Solubilization of paclitaxel using polymeric micelles of poly(ethylene glycol)-b-P(D,L-lactide) (PEG-b-PLA) served as a control for the stability study. Up to 37.4 wt % paclitaxel could be loaded in PEG-b-P(VBODENA) micelles, whereas the maximum loading amount for PEG-b-PLA micelles was 27.6 wt %. Thermal analysis showed that paclitaxel in the polymeric micelles existed in the molecularly dispersed amorphous state even at loadings over 30 wt %. Paclitaxel-loaded hydrotropic polymeric micelles retained their stability in water for weeks, whereas paclitaxel-loaded PEG-b-PLA micelles precipitated in a few days. Hydrotropic polymer micelles were more effective than PEG-PLA micelle formulations in inhibiting the proliferation of human cancer cells. Paclitaxel in hydrotropic polymer micelles was administered orally (3.8 mg/kg), intravenously (2.5 mg/kg), or via the portal vein (2.5 mg/kg) to rats. The oral bioavailability was 12.4% of the intravenous administration. Our data suggest that polymeric micelles with a hydrotropic structure are superior as a carrier of paclitaxel due to a high solubilizing capacity combined with long-term stability, which has not been accomplished by other existing polymeric micelle systems. 相似文献
4.
Development and evaluation of a protein microarray chip for diagnosis of hepatitis C virus 总被引:3,自引:0,他引:3
A protein chip diagnostic kit was developed for the diagnosis of hepatitis C virus (HCV) based on the protein chip technique and the immuno-concentration method. This kit was designed for low-density protein chips and also for the availability of multiple sample screening. Applicability of the chip was evaluated using 96 blood specimens and the results were compared to results of an anti-HCV enzyme immunoassay (EIA) test. With further development, the technology associated with the development of this chip could be applied to the simultaneous detection of multiple protein-protein, protein-ligand interactions. 相似文献
5.
Myung Soo Park Seung-Yoon Oh Hae Jin Cho Jonathan J. Fong Woo-Jae Cheon Young Woon Lim 《Antonie van Leeuwenhoek》2014,106(4):593-603
A new species, Trichoderma songyi, was found to be associated with the pine mushroom (Tricholoma matsutake) in Korea. This species was isolated from three different substrates: Tricholoma matsutake basidiomata, as well as roots of Pinus densiflora and soil in the fairy ring. Based on its molecular and phenotypic characteristics, we demonstrate that Trichoderma songyi is unique and distinguishable from closely related species. We performed phylogenetic analyses based on two molecular markers, the genes for both translation elongation factor 1-alpha and the second largest subunit of RNA polymerase II. Phylogenetic analyses showed that Trichoderma songyi is closely related to Trichoderma koningii aggregate and Trichoderma caerulescens. Morphologically, Trichoderma songyi can be distinguished from these closely related taxa by its growth rates, colony morphology on PDA in darkness, and coconut-like odour. Due to the economic importance of the pine mushroom, the relationship between Trichoderma songyi and Tricholoma matsutake should be studied further. 相似文献
6.
Decreased severity of potato common scab after foliar sprays of 3,5 -dichlorophenoxyacetic acid, a possible antipathogenic agent 总被引:1,自引:0,他引:1
BY A. H. MCINTOSH G. L. BATEMAN K. CHAMBERLAIN G. W. DAWSON M. M. BURRELL 《The Annals of applied biology》1981,99(3):275-281
Glasshouse tests on the potato cultivars Majestic and Maris Bard measured the effects of single early foliar sprays of ring-substituted phenoxyacetic acids (0.9 × 10–3 M) on the incidence of potato common scab, caused by soil-borne Streptomyces scabies. The most effective compound was 3,5-dichlorophenoxyacetic acid (3,5-D), which decreased scab by about 90%; its action was preventative, early sprays being more effective than late However, it slightly decreased yield, and increased the number of tubers per plant and the proportion of deformed tubers. The trichloro- and tetrachloro- acids containing the 3,5-dichloro- group also decreased scab, though to lesser extents; the most active of these was the 2,3,4,5-tetrachloro- acid, which had the same side effects as 3,5-D. The herbicide 2,4-D almost halved scab incidence, but seriously decreased yield. Other acids tested had little or no effect on scab. In tests against S. scabies in culture, 3,5-D was no more toxic than other disubstituted acids which were inactive, or weakly active, against the disease in vivo. 3,5-D may be an ‘antipathogenic agent’, preventing scab development by altering tuber metabolism. 相似文献
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So-Jung Kwon Kyuyong Han Suhyun Jung Jong-Eun Lee Seongsoon Park Yong-Pil Cheon Jade Hyunjung Lim 《BMC biotechnology》2009,9(1):73