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RIG-1 signalling is responsible for the detection of cytoplasmic viral RNA molecules. DEXH (Asp-Glu-X-His) box polypeptide 58 (encoded by DHX58) is a negative regulator of the RIG-1 signalling pathway. In human, the DHX58 gene can be upregulated and can inhibit the RIG-1 signalling pathway during viral infection. In this study, porcine DHX58 gene expression patterns were studied. According to our results, the porcine DHX58 gene was upregulated not only by the stimulation of Poly I:C but also by the stimulation of 1ipopolysaccharides (LPS). One polymorphism (g.4919G>C), detected in the ninth intron, was significantly associated with some blood parameters including the red cell distribution width of 1-day-old pigs and white blood cell counts, lymphocyte absolute counts, and platelet distribution width of 17-day-old pigs (P < 0.05). Moreover, the individuals with the genotype GG have a significantly higher mean white blood cell count than individuals with genotype CC or GC (P < 0.05). Our study indicates that DHX58 is an important gene that is associated with the immune response in swine.  相似文献   
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Embryos of most fish develop externally and are exposed to an aquatic environment full of potential pathogens, whereas they have little or only limited ability to mount an efficient and protective response. How fish embryos survive pathogenic attacks remains poorly defined. Here we demonstrate that the maternal immunization of female zebrafish with formalin-killed Aeromonas hydrophila causes a significant increase in C3 and Bf contents in the mother, a corresponding rise in the offspring, and induces a remarkable increase in the hemolytic activities in both the mother and offspring. In addition, the embryos derived from the immunized mother are significantly more tolerant to A. hydrophila challenge than those from the unimmunized fish, and blocking C3 and Bf activities by injection of the antibodies against C3 and Bf into the embryos render them more susceptible to A. hydrophila. These results clearly show that the protection of zebrafish embryos against A. hydrophila can be achieved by the maternally-transferred immunity of the complement system operating via the alternative pathway. This appears to be the first report providing in vivo evidences for the protective role of the alternative complement components in the early embryos of zebrafish, paving the way for insights into the in vivo function of other maternally-transferred factors in fish.  相似文献   
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Raman spectra have been obtained for dTMP and its complex with CH3Hg (II) in aqueous solution as a function of pH. Difference spectroscopy is employed to increase the sensitivity of the Raman technique. The binding reaction is essentially quantitative from pH 3 to 9, and the value of the equilibrium constant for CH3HgOH2+ + dThd in equilibrium CH3Hg(dThdH--1) + H30+ is estimated from intensity measurements to be 0.6 in reasonable agreement with an earlier value based upon uv spectrophotometric data. Binding is to N(3) with substitution of CH3Hg+ for the proton. A similar reaction occurs with 1-MeThy. Raman spectra for aqueous and crystalline 1-MeThy and for the complex CH3Hg(1-MeThyH--1) are reported. The spectrum of crystalline Hg(1-MeThyH--1)2, for which the crystal structure is known, also was obtained for comparison. Raman difference spectroscopy was used to confirm that CH3Hg (II) binds to N(3) of dTMP and N(1) of GMP at r = 0.2 (MeHg+: phosphate) ratios with mixtures of GMP + CMP + AMP + dTMP. In contrast, native calf thymus DNA does not appear to bind CH3Hg(II) at these sites at r = 0.15, although no significant amount of free CH3HgOH is present. With r = 0.3, extensive binding occurs both to the Thy and Gua bases. Raman difference spectroscopy is a valuable technique for studying the binding of ions and molecules to polynucleotides in moderately dilute aqueous solution.  相似文献   
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The segmentum accelerans in geese is a constriction in the caudal end of the primary bronchus. Experimental evidence suggests that this part of the airway functions as an inspiratory aerodynamic valve, accelerating the incoming airstream past the ventrobronchial openings. The luminal diameter of the segmentum accelerans dilates in the presence of elevated CO2 levels, probably through relaxation of smooth muscle. Physiological control of the segmentum accelerans may permit inspiratory aerodynamic valving to be maintained throughout a wide range of ventilatory flows.  相似文献   
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