Oxidation and polymer degradation characteristics of high viscosity modified asphalts under various aging environments.

High viscosity modified asphalt (HVMA) was the core material to build ecological permeable pavement, while it was prone to aging, which limited its applications for urban sustainability. This study focused on the oxidation and polymer degradation characteristics of the high-content styrene-butadiene-styrene modified asphalt, high-viscosity composite particle modified asphalt and high-elastic modified asphalt under the simulated aging environments of thermal oxidation and weather. Gel permeation chromatography results showed that the increase percent of large molecular size percent and the decrease percent of polymer weight could characterize the oxidation degree and polymer degradation degree, respectively. The degrees of oxidation and polymer degradation in all HVMAs increased synchronously with aging, and reached the highest after the weather aging. The polymer molecular distribution of HVMA would become more uniform with aging from the proposed ratio of polymer weight to polymer content. Dynamic shear rheometer tests reflected that there existed the dual effects of coupling and parallelism during aging of HVMA, i.e. the oxidation-induced hardening effect and degradation-induced softening effect. Furthermore, the change percent of rheological indicators was proposed as the net aging degree. Considering the rheological properties of aged HVMA were the coupling results of dual effects, the net aging degree could represent the oxidation dominance degree or polymer degradation dominance degree of HVMA. Due to the differences of dual effects and polymer molecular distribution, various HVMAs showed the totally different net aging degree ranking, depending on the aging states and rheological indicators. Notably, the high-elastic modified asphalt showed the greatest aging resistance at all aging states as a result of its weak dual effects and most uniform polymer molecular distribution.

Musashi1 inhibit the release of Newcastle disease viruses through preventing apoptosis of DF-1 cells.

The efficient proliferation of Newcastle disease virus (NDV) depends on its inhibition of host cell innate immunity. V protein acts as a nonstructural protein which plays a significant role in virus replication, whereas its function remains to be further explored. In this study, Musashi RNA binding protein 1 (MSI1) was selected and its interaction with V protein was further verified by Co-immunoprecipitation (Co-IP) and Immuno-colocalization test. Through the transfection of pCMV-HA-MSI1 in DF-1 cells, the overexpression of MSI1 reduced virus particles in the cell supernatant but not reduced mRNA and virus protein in cells pellet, which suggests that MSI1may act as a new antiviral molecule by inhibiting viral release. Cell early apoptosis was detected by flow cytometry (FCM), the result shows that overexpression of MSI1 inhibit cell apoptosis, implying MSI1 Inhibit virus release may through this way. Taken together, MSI1 and NDV V protein has a detectable interaction, and may block apoptosis to inhibit the release of NDV. However, this is the first report about the interaction between MSI1 and V protein of NDV that can inhibit the NDV replicated.

Screening and mechanistic study of key sites of the hemagglutinin-neuraminidase protein related to the virulence of Newcastle disease virus.

Newcastle disease is a kind of avian infectious disease caused by Newcastle disease virus (NDV). The virulence of NDV is dependent mainly on the fusion (F) protein and hemagglutinin-neuraminidase (HN) protein. The genomes of 2 viruses, NDV-Blackbird and NDV-Dove, are 99.9% similar, while NDV-Blackbird is a velogenic virus, and NDV-Dove is a lentogenic virus. Further analysis revealed that the F proteins of the 2 strains were identical, and only 5 amino acid sites on the HN proteins were inconsistent. Five different HN mutant plasmids were constructed and analyzed in this study. The results showed that the mutation F110L caused a significant increase in fusion-promotion activity caused by an increase in neuraminidase activity. Because of the increase in receptor-binding activity caused by G116R, there was a significant increase in fusion-promotion activity. The mutation G54S resulted in a slight decrease in the fusion-promotion activity caused by a slight decrease in receptor-binding activity. The slight increase in the fusion-promotion activity caused by A469V was associated with a significant increase in neuraminidase activity. Therefore, the amino acids L110 and R116 played a key role in determining the virulence difference between NDV-Blackbird and NDV-Dove, which could lay a foundation for illuminating the virulence differences of NDV strains, as well as the development of attenuated vaccines.

Ivermectin inhibits DNA polymerase UL42 of pseudorabies virus entrance into the nucleus and proliferation of the virus in vitro and vivo.

Pseudorabies virus (PRV) is an important viral pathogen of pigs that causes huge losses in pig herds worldwide. Ivermectin is a specific inhibitor of importin-α/ß-dependent nuclear transport and shows antiviral potential against several RNA viruses by blocking the nuclear localization of viral proteins. Since the replication of DNA viruses is in the nucleus, ivermectin may be functional against DNA virus infections if the DNA polymerase or other important viral proteins enter the nucleus via the importin-α/ß-mediated pathway. Here, we determined whether ivermectin suppresses PRV replication in hamster kidney BHK-21 cells and investigated the effect of ivermectin on the subcellular localization of the PRV UL42 protein, the accessory subunit of PRV DNA polymerase. Also, an in vivo anti-PRV assay was conducted in mice. Our data demonstrate that ivermectin treatment inhibits PRV infection in cells in a dose-dependent manner. Treatment of PRV-infected cells with ivermectin significantly suppressed viral DNA synthesis and progeny virus production. Ivermectin disrupted the nuclear localization of UL42 by targeting the nuclear localization signal of the protein in transfected cells. Ivermectin treatment increased the survival rates of mice infected with PRV and relieved infection as indicated by lower clinical scores and fewer gross lesions in the brain. Together, our results suggest that ivermectin may be a therapeutic or preventative agent against PRV infection.

Common microRNA⁻mRNA Interactions in Different Newcastle Disease Virus-Infected Chicken Embryonic Visceral Tissues.

To investigate the roles and explore the altered expression of microRNAs (miRNAs) and mRNAs in chicken embryos in response to Newcastle disease virus (NDV) infection, deep sequencing was performed. Then, a conjoint analysis of small RNA-seq and mRNA-seq was performed to screen interactional miRNA⁻mRNA pairs during NDV infection. In total, 15 and 17 up- and downregulated miRNAs were identified that potentially targeted 4279 and 6080 mRNAs in NDV-infected chicken embryonic tissues, respectively; in addition, 595 upregulated and 480 downregulated mRNAs were identified. The conjoint analysis of the obtained data identified 1069 miRNA⁻mRNA pairs. Among these pairs, 130 pairs were related to immune or inflammatory responses. The relationship between gga-miR-203a and its target transglutaminase 2 (TGM2) was confirmed using a dual-luciferase reporter system and a real time quantitative polymerase chain reaction (RT-qPCR) assay. Overall, the discovery of miRNAs, mRNAs, and their potential pairing relationships, which may be involved in the regulation of NDV infection, will facilitate our understanding of the complex regulatory relationship between the host and the virus.