Toll-like receptor 7 (TLR7) is activated by single-stranded RNA and synthetic imidazoquinoline components, and induces interferon production. In this study, we cloned the TLR7 gene from King pigeon (Columba livia). The TLR7 open reading frame is 3144 bp and encodes a 1047-amino acid protein, consisting of a canonical TLR composition with 15 leucine-rich repeats (LRRs). Amino acid-inserting modifications were found at position 15 of LRR2, LRR11, LRR13, and LRR14 and position 10 of LRR10. The tissue distribution of pigeon TLR7 suggests that immune-associated tissues, especially the spleen and liver, have high TLR7 expression. HEK293T cells transfected with pigeon TLR7 plasmid responded to the agonist R848, indicating a functional TLR7 homolog. Following R848 stimulation of pigeon peripheral blood mononuclear cells, the levels of IFN-γ, IL-6, IL-8, CCL5, and IL-10 mRNA, assessed using quantitative real-time PCR, were significantly up-regulated. After Newcastle disease virus vaccine strain LaSota inoculation and agonist R848 injection, the level of TLR7 mRNA in the spleen of pigeons increased significantly in the R848-injected group, but decreased in the LaSota-inoculated group at three day post-infection (d.p.i.). The mRNA levels of inflammatory cytokines and chemokines were significantly upregulated in both LaSota-inoculated and R848-injected groups. Triggering pigeon TLR7 leads to robust up-regulation of inflammatory cytokines and chemokines, suggesting an important role in the innate immune response. 相似文献
Tetrahedral DNA hybrids with tetrakis(p‐hydroxyphenyl)methane cores hybridize in a sequence‐specific fashion at much higher temperatures than isolated linear duplexes. Dinucleotide DNA arms suffice to induce the formation of a solid at room temperature; this demonstrates the strength of multivalent binding. The graphic shows a view of a modeled assembly.
In this paper we introduce a new test of the null hypothesis of no cointegration between a pair of time series. For a very simple generating model, our test compares favourably with the Engle–Granger/Dickey–Fuller test and the Johansen trace test. Indeed, shortcomings of the former motivated the development of our test. The applicability of our test is extended to series generated by low-order vector autoregressions. Again, we find evidence that this general version of our test is more powerful than the Johansen test. The paper concludes with an empirical example in which the new test finds strong evidence of cointegration, but the Johansen test does not. 相似文献
Refractories and Industrial Ceramics - The article is devoted to the preparation of ecologically clean composites by powder metallurgy and the study of tribological properties. Tribological tests... 相似文献
A direct comparison on solids flux was enabled by measurements obtained in a pair of riser and downer circulating fluidized bed reactors, of the same diameter, using suction probes. The operating conditions and the axial position were found to affect the solids flux in each reactor in a different manner. The solids flux in the riser were affected to a large degree by the gas velocity, in contrast with the downer where no visible effect was detected from changes in the gas velocity. The axial position has an effect on the shape of the solids flux profiles in the downer, but only small effects were observed in the riser. On the other hand, increases in overall solids flux leads to the increase of local solids flux in both the downer and the riser. 相似文献
