In this study, antibody responses after vaccination against equine influenza were investigated among 1,591 horses in the Republic of Korea using the hemagglutination inhibition (HI) test. Equine influenza has not occurred since 2011 and a commercial vaccine against H3N8 has been used. The equine influenza virus, A/equine/South Africa/4/03 (H3N8), was used as the antigen in the HI assay. The mean seropositive rate was 90.5% in 2019. Except for stallion whose seropositive rate was 78.5%, all seropositive rates of other horse types were over 90%. Regionally, except for Gangwon-do and Jeju-do whose seropositive rates were 89.0% and 87.1%, all seropositive rates in other provinces were over 90%. In the future, more through vaccination against equine influenza needs to be done based on this investigation result.

Viral protein 2 (VP2), which is the structural protein of parvovirus, can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. VP2 of canine parvovirus (CPV) is responsible for neutralizing antibodies in immunized animals. In this study, VP2 protein of canine parvovirus-2c was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells. The results show that VP2 proteins assembled into virus-like particles (VLPs) with antigenic properties similar to those of natural CPV and a high hemagglutination (HA) titer (1:27). The recombinant 6-His-tagged VP2 protein with a molecular mass of about 65 kDa was detected by anti-His antibody and anti-PPV serum. This study provides a foundation for the application of VP2 protein in the clinical diagnosis of CPV and in the vaccination against CPV.

Two different casting speeds of 60 and 80mm/min are adopted to determine the effect of casting speed on the microstructure and mechanical properties of Al-Mg-Si/Al hybrid material prepared by duo-casting. The obtained hybrid material has a uniform and straight macro-interface between the pure Al side and the Al-Mg-Si alloy side at both casting speeds. When the casting speed is increased to 80mm/min, the size of primary α phases in Al-Mg-Si alloy decreases, without change of shape. Although the Al-Mg-Si alloy produced at higher casting speed of 80mm/min shows much higher ultimate tensile strength (UTS) and 0.2 % proof stress and lower elongation, along with higher bending strength compared to the case of the 60mm/min in casting speed, the tensile properties and bending strength of the hybrid material, which are similar to those of pure Al, are the same regardless of the increase of casting speed. Despite the different casting speeds, deformation and fracturing in hybrid materials are observed only on the pure Al side. This indicates that the macro-interface is well-bonded, allowing it to endure tensile and bending deformation in all hybrid materials.

Royal jelly (RJ) is a gelatinous substance that bees produce to feed bees and queen bees. It’s frequently sold as a dietary supplement to treat a variety of physical ailments and chronic diseases. While it has long been used in traditional medicine, its applications in Western medicine remain controversial. The inhibitory effect of royal jelly on osteoarthritis was investigated in primary cultured rat cartilage cells and monosodium-iodoacetate (MIA)-induced arthritis rat model 10-hydroxy-2-decenoic acid (10-HAD) is the main fatty acid present in RJ. Among the criteria for RJ quality analysis, 10-HAD content has been proposed as a freshness parameter. We investigated the effect of RJ on the improvement of osteoarthritis on SD rats and they were divided into five groups. In this study, we examined the effect of enzymatic royal jelly (ERJ) administration on osteoarthritis. To determine the antiinflammatory effects of RJ, tumor necrosis factor alpha (TNF-α) and Interleukin-6 (IL-6) expression were measured after lipopolysaccharide (LPS) activation in RAW 264.7 cells. In in vivo animal study, osteoarthritis was induced by intra-articular injection of MIA into knee joints of rats. As a results, ERJ showed that TNF-α and IL-6 levels were decreased by ERJ treatment in a dosedependent manner. In conclusion, ERJ extract was able to inhibit articular cartilage degeneration by preventing extracellular matrix degradation and cartilage cell damage. It was considered that ERJ extract may be a potential therapeutic treatment for degenerative osteoarthritis.

In this study, three kinds of metal chills such as SS400, AC4CH and brass, with different thicknesses of 40 ~ 80 mm, were applied for low pressure casting of Al-Si alloy to control cooling rate. The microstructural characteristics with increasing cooling rate were represented using factors including D1, D2, size of primary α phases and shape factor and size of eutectic Si. The tensile properties were investigated and additionally analyzed based on the microstructural characteristics. As the cooling rate increased, D1, D2, and sizes of primary α phases and eutectic Si apparently decreased and the shape factor of eutectic Si increased to over 0.8. The ultimate tensile strength (UTS) and yield strength (YS) increased with decreasing D1, D2, and size of primary α phases, while elongation increased with decreasing size of eutectic Si and concurrently increasing shape factor of eutectic Si. This indicated that the primary α phases and eutectic Si in Al-Si alloy were refined with increasing cooling rate, resulting in improvement of UTS and YS without sacrificing elongation. After the tensile test, preferential deformation of primary α phases was observed in the Al-Si alloy produced at higher cooling rates of more than 0.1 K/s.