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Background: Cecropin P1, acting as an antimicrobial, has a broad-spectrum antibacterial activity with some antiviral and antifungal properties. It is a promising natural alternative to antibiotics which is originally isolated from the pig intestinal parasitic nematode Ascaris suum . Many studies have shown that Cecropin P1 is helpful for the prevention or treatment of clinical diseases. Therefore, it is very necessary to establish a safe, nontoxic, and efficient expression method of Cecropin P1. Results: The results indicated that the recombinant protein was about 5.5 kDa showed by Tricine–SDS–PAGE and Western blot. And Cecropin P1 was efficiently secreted and expressed after 12 h of induction, with an increasing yield over the course of the induction. Its maximum concentration was 7.83 mg/L after concentration and purification. In addition, in vitro experiments demonstrated that Cecropin P1 not only exerted a strong inhibitory effect on Escherichia coli , Salmonella sp., Shigella sp., and Pasteurella sp., but also displayed an antiviral activity against PRRSV NADC30-Like strain. Conclusions: Collectively, the strategy of expressing Cecropin P1 in Saccharomyces cerevisiae is harmless, efficient, and safe for cells. In addition, the expressed Cecropin P1 has antiviral and antibacterial properties concurrently. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0cm; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

To improve the mechanical properties of hot-deformed Nd-Fe-B magnets, anisotropic Nd-Fe-B magnets doped with SiC whiskers were fabricated by hot-pressing and hot-deformation processes. The influence of the SiC whiskers on the microstructure and magnetic and mechanical properties of the Nd-Fe-B magnets was investigated. The bending strength of the hot-deformed Nd-Fe-B magnets reinforced with SiC whiskers first increased and then decreased with increasing SiC whisker content from 0 wt.% to 1.0 wt.%. The composite magnet with 0.5 wt.% SiC whiskers exhibited the highest average bending strength and still retained the maximum energy product of approximately 45.8 MGOe. The morphology of the fracture surface of the magnets revealed that the majority of the SiC whiskers were distributed at intergranular boundaries. The phenomenon of SiC whisker pullout from the matrix was observed, which results in increased bending strength. The improvement of the mechanical properties can be attributed to the high strength of the SiC whiskers, the whisker pullout phenomenon, and crack deflection.

Haemophilus parasuis (H. parasuis) is a conditional pathogen with the ability to form biofilms which can lead to ineffective drug treatment and severe chronic infections resulting in significant economic losses to the pig industry. Currently, knowledge of biofilm formation by H. parasuis is not well developed. The objective of this study was to investigate the three-dimensional morphology of biofilms and perform transcriptomic analysis on H. parasuis cells in biofilm versus planktonic forms. The results showed that proteins and DNA accounted for a large proportion of the H. parasuis biofilm extracellular matrix. Here, we have traced the entire biofilm formation process of H. parasuis from beginning to end for the first time. These biofilms grew rapidly in the first 48 h and became stable at 60 h. According to GO and KEGG analysis, the differentially expressed genes (DEG) artM, artQ, ssrS, pflA and HutX were implicated as being involved in bacterial colonisation and adhesion; these are the most likely genes to affect biofilm formation. Most functional gene enrichments were of those involved in metabolic pathways, biosynthesis of secondary metabolites, ATP-binding cassette (ABC) transporters, and starch and sucrose metabolism. Thus, in the present pilot study, the composition and characteristics of these biofilms were explored, and the genes related to biofilm formation were screened for. This research lays the foundation for further studies on mechanisms regulating biofilm formation, in order to find new drug targets and develop new therapeutic drugs against H. parasuis.

The important data supporting the conclusion of the manuscript is submitted to Geophysical Research Letters.

This study aims to establish a rapid detection method for antibody against rabbit hemorrhagic disease virus (RHDV) by using immunochromatography technology. The colloidal gold-labeled recombinant VP60 protein, anti-VP60 polyclonal antibody and goat anti-rabbit IgG were coated on quality control line (C line) and detection line (T line). The test strip preparation conditions were optimized by detecting positive serum and negative serum. The results showed that the T-line and C-line were all red when tested positive serums. But only the C-line was red on the negative strips, the T-line was not colored, the false positive rate and the false negative rate were all zero percent. The specificity, sensitivity and reproducibility tests results all indicated that the colloidal gold strip is a powerful testing tool for the epidemiological investigation and detection of the antibody level on viral hemorrhagic disease in rabbits.

Single-grain models with different cerium contents or structural parameters have been introduced to investigate the reversal magnetization behaviors in cerium-containing magnets. All the micromagnetic simulations are carried out via the object oriented micromagnetic framework (OOMMF). As for single (Nd,Ce)2Fe14B type grain, the coercivity decreases monotonously with the increase of the cerium content. Four types of grain structure have been compared: single (Nd,Ce)2Fe14B type, core ((Nd,Ce)2Fe14B)–shell (Nd2Fe14B) type with 2 nm thick shell, core (Ce2Fe14B)–shell (Nd2Fe14B) type, and core (Nd2Fe14B)–shell (Ce2Fe14B) type. It is found that core ((Nd,Ce)2Fe14B)–shell (Nd2Fe14B) type grain with 2 nm thick shell always presents the largest coercivity under the same total cerium content. Furthermore, the relationship between the coercivity and the shell thickness t in core ((Nd,Ce)2Fe14B)–shell (Nd2Fe14B) type grain has been studied. When the total cerium content is kept at 20.51 at.%, the analyzed results show that as t varies from 1 nm to 7 nm, the coercivity gradually ascends at the beginning, then quickly descends after reaching the maximum value when t = 5 nm. From the perspective of the positions of nucleation points, the reasons why t affects the coercivity are discussed in detail.