No abstract

No abstract

The grass carp (Ctenopharyngodon idella) is an important commercial farmed herbivorous fish species in China, but is susceptible to Aeromonas hydrophila infections. In the present study, we performed de novo RNA-Seq sequencing of spleen tissue from specimens of a disease-resistant family, which were given intra-peritoneal injections containing PBS with or without a dose of A. hydrophila. The fish were sampled from the control group at 0 h, and from the experimental group at 4, 8, 12, 24, 48 and 72 h. 122.18 million clean reads were obtained from the normalized cDNA libraries; these were assembled into 425,260 contigs and then 191,795 transcripts. Of those, 52,668 transcripts were annotated with the NCBI Nr database, and 41,347 of the annotated transcripts were assigned into 90 functional groups. 20,569 unigenes were classified into six main categories, including 38 secondary KEGG pathways. 2,992 unigenes were used in the analysis of differentially expressed genes (DEGs). 89 of the putative DEGs were related to the immune system and 41 of them were involved in the complement and coagulation cascades pathway. This study provides insights into the complement and complement-related pathways involved in innate immunity, through expression profile analysis of the genomic resources in C. idella. We conclude that complement and complement-related genes play important roles during defense against A. hydrophila infection. The immune response is activated at 4 h after the bacterial injections, indicating that the complement pathways are activated at the early stage of bacterial infection. The study has improved our understanding of the immune response mechanisms in C. idella to bacterial pathogens.

Electrical stimulation may improve the proliferation of animal cells. In the present study, osteoblasts were cultured on electroactive aniline pentamer (AP)/poly(lactic-co-glycolic acid) (PLGA) copolymer composites, on which electric pulse was imposed. The combination of polymer and electric pulse enhanced the osteogenic differentiation of the osteoblasts, characterized by the upregulated expression of bone morphogenetic protein (BMP)-2, collagen I and osteonectin and the phosphorylation of Samd4, in contrast to polymer or electrical pulse alone. This action occurred in a polymer content-dependent manner. Therefore, the action of the electric pulse, assisted by the electroactive polymer implant, may be promising in the expedition of injured bone repair.