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Innate immunity plays an essential role in preventing the invasion of pathogenic microorganisms. However, innate immunity is a double-edged sword, whose excessive activation is detrimental to immune homeostasis and even leads to a “cytokine storm” of the infected host. The host develops a series of negative regulatory mechanisms to balance the immune response. Here, we report a negative regulatory mechanism of chicken innate immunity mediated by miRNA. In the GEO database, we found that miR-126-5p was markedly up-regulated in chickens infected by RNA viruses. Upregulation of miR-126-5p by RNA virus was then further shown via both a cell model and in vivo tests. Overexpression of miR-126-5p significantly inhibited the expression of interferon and inflammatory cytokine-related genes induced by RNA viruses. The opposite result was achieved after the knockdown of miR-126-5p expression. Bioinformatics analysis identified TRAF3 as candidate target gene of miR-126-5p. Experimentally, miR-126-5p can target TRAF3, as shown by the effects of miR-126-5p on the endogenous expression of TRAF3, and by the TRAF3 3'UTR driven luciferase reporter assay. Furthermore, we demonstrated that miR-126-5p negatively regulated innate immunity by blocking the MAVS-TRAF3-TBK1 axis, with a co-expression assay. Overall, our results suggest that miR-126-5p is involved in the negative regulation of chicken innate immunity, which might contribute to maintaining immune balance.

Traditional waterborne polyurethane (WPU) has poor water resistance because of the incorporation of permanent hydrophilic groups, such as carboxyl group or ammonium salt, into polymer chains. Therefore, developing WPU with excellent water resistance and mechanical properties is highly desirable for industrial applications. In this study, CO2-triggered hydrophobic/hydrophilic switchable waterborne polyurethane–acrylate (WPUA) containing methyl methacrylate (MMA) units were designed and synthesized. The molecular structure, hydrophobic/hydrophilic switchable behavior, water resistance, and mechanical properties were systematically investigated and characterized. The WPUA with 10 wt% MMA exhibited a low water uptake (2.15 wt%) and linear swelling ratio (0.17 L%), as well as a high tensile strength (16.7 MPa) and modulus (85.9 MPa), which were much higher than those of the pristine WPU. This study indicated that the CO2-triggered WPUA dispersed stably as latex particles in water and possessed excellent water resistance and mechanical properties after the film formation.

Cu9Ni6Sn alloys were prepared by conventional casting (CC) and twin-roll casting (TRC). The CC-processed specimens possessed dendritic structures, and Sn was distributed mainly in the inter-dendritic region and formed dendritic segregation. The TRC-processed specimens were composed of equiaxed grains and a heterogeneous structure. The distribution of Sn showed gradient characteristics, with more Sn in the surface layer and less Sn in the center. The TRC-processed specimens had more inhomogeneous mechanical properties than the CC-processed specimens.