N123I mutation in the ALV-J receptor-binding domain region enhances viral replication ability by increasing the binding affinity with chNHE1.

The subgroup J avian leukosis virus (ALV-J), a retrovirus, uses its gp85 protein to bind to the receptor, the chicken sodium hydrogen exchanger isoform 1 (chNHE1), facilitating viral invasion. ALV-J is the main epidemic subgroup and shows noteworthy mutations within the receptor-binding domain (RBD) region of gp85, especially in ALV-J layer strains in China. However, the implications of these mutations on viral replication and transmission remain elusive. In this study, the ALV-J layer strain JL08CH3-1 exhibited a more robust replication ability than the prototype strain HPRS103, which is related to variations in the gp85 protein. Notably, the gp85 of JL08CH3-1 demonstrated a heightened binding capacity to chNHE1 compared to HPRS103-gp85 binding. Furthermore, we showed that the specific N123I mutation within gp85 contributed to the enhanced binding capacity of the gp85 protein to chNHE1. Structural analysis indicated that the N123I mutation primarily enhanced the stability of gp85, expanded the interaction interface, and increased the number of hydrogen bonds at the interaction interface to increase the binding capacity between gp85 and chNHE1. We found that the N123I mutation not only improved the viral replication ability of ALV-J but also promoted viral shedding in vivo. These comprehensive data underscore the notion that the N123I mutation increases receptor binding and intensifies viral replication.

OASL suppresses infectious bursal disease virus replication by targeting VP2 for degrading through the autophagy pathway.

Infectious bursal disease (IBD) is an acute and fatal immunosuppressive disease caused by infectious bursal disease virus (IBDV). As an obligate intracellular parasite, IBDV infection is strictly regulated by host factors. Knowledge on the antiviral activity and possible mechanism of host factors might provide the theoretical basis for the prevention and control of IBD. In this study, RNA-sequencing results indicated that many host factors were induced by IBDV infection, among which the expression levels of OASL (2´,5´-oligadenylate synthetase-like protein) was significantly upregulated. OASL overexpression significantly inhibited IBDV replication, whereas OASL knockdown promoted IBDV replication. Interestingly, the antiviral ability of OASL was independent of its canonical enzymatic activity, i.e., OASL targeted viral protein VP2 for degradation, depending on the autophagy receptor p62/SQSTM1 in the autophagy pathway. Additionally, the 316 lysine (K) of VP2 was the key site for autophagy degradation, and its replacement with arginine disrupted VP2 degradation induced by OASL and enhanced IBDV replication. Importantly, our results for the first time indicate a unique and potent defense mechanism of OASL against double-stranded RNA virus by interaction with viral proteins, which leads to their degradation. IMPORTANCE: OASL (2´,5´-oligadenylate synthetase-like protein) exhibits broad-spectrum antiviral effects against single-stranded RNA viruses in mammals, potentially serving as a promising target for novel antiviral strategies. However, its role in inhibiting the replication of double-stranded RNA viruses (dsRNA viruses), such as infectious bursal disease virus (IBDV), in avian species remains unclear. Our findings indicated a unique and potent defense mechanism of OASL against dsRNA viruses. It has been previously shown in mammals that OASL inhibits virus replication through increasing interferon production. The groundbreaking aspect of our study is the finding that OASL has the ability to interact with IBDV viral protein VP2 and target it for degradation and thus exerts its antiviral effect. Our results reveal the interaction between avian natural antiviral immune response and IBDV infection. Our study not only enhances our understanding of bird defenses against viral infections but can also inform strategies for poultry disease management.

The Role of Reduced Graphene Oxide in Enhancing the Mechanical and Thermal Properties of a Rubber Cover Joint.

The development of high-performance rubber composites has always been a research hotspot in the field of conveyor belt manufacturing. In this work, a rubber cover joint composite made of reduced graphene oxide (rGO) was prepared using latex mixing and mechanical blending methods, with a steel wire rope conveyor belt as the research object, and the influence of the rGO content on the properties of the rubber composite is discussed. The structure and morphology characterization of the rGO/NR rubber show that the addition of rGO does not change its crystal structure, and 1.2 phr rGO is uniformly dispersed throughout the rubber composite. As more rGO is added, the mechanical properties of the rGO rubber cover joint first improve and then worsen. With the addition of 1.2 phr, the cross-linking density increases by 80.6%, the tensile strength of the rubber composites increases by 49.7%, the elongation at break increases by 23.6%, and the adhesion strength increases by 12.4%. The tensile strength of the rGO rubber cover joint can still maintain 72.5% of its pre-thermal aging value. The wear resistance and thermal conductivity increase as more phr is added. When 3.0 phr is added, the wear resistance of the rubber composites increases by 32.9%, the thermal conductivity increases by 118.8%, and the temperature difference at the completion of vulcanization decreases from 4.5 °C to 1.8 °C. The results show that when 1.2 phr of rGO is added, the rubber conveyor belt joint obtains the best comprehensive performance. These enhanced comprehensive properties allow for the practical application of rGO nanomaterials to conveyor belt rubber.

Effects of acupoint injection for stroke patients with hemiplegia: A protocol for systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Acupoint injection has currently received increasing attention as a treatment for hemiplegia. A number of studies have reported that acupoint injection have some advantages in treatment of hemiplegia. However, currently no article has summarized the existing evidence. Our study will evaluate the efficacy and safety of acupoint injection as a clinical treatment for hemiplegia, so that it can provide an important reference for clinical decision-making. METHODS: Randomized controlled trials and case control studies of acupoint injection for hemiplegia according to the included and excluded standard were identified in searches of 6 databases from their inception to February 2021. All data were assessed and extracted by 2 authors independently. The risk of bias assessment recommended by the Cochrane Collaboration was used to assess the quality of the selected studies. Review Manager 5.4 (Cochrane Collaboration) was used to conduct meta-analysis for the efficacy and safety of acupoint injection. RESULT: The results of this systemic review and meta-analysis will be submitted to a recognized journal for publication. CONCLUSION: This systemic review and meta-analysis will evaluate the efficacy and safety of acupoint injection as a clinical treatment for hemiplegia. We hope this study can make a definitive conclusion for acupoint injection in the treatment of hemiplegia. REGISTRATION: PROSPERO (registration number CRD42021234453).