Since the first detection of African swine fever (ASF)-infected wild boar in October 2019, the ASF virus has been circulating among wild boars in the Republic of Korea. The priority for ASF control is to understand the epidemic situation correctly. The basic reproduction number (R0) can be used to describe the contagious disease epidemic situation since it can assess the contagiousness of infectious agents by presenting the average number of new cases generated by an infected case. The current study estimated R0 for the 2019/20 ASF epidemics in wild boars in the Republic of Korea using the reported number of ASF cases and a serial interval of the ASF virus. The estimated mean R0 was 2.10 (range: 0.06 – 10.24) for the 2019/20 ASF epidemics, 2.94 (range: 0.43 – 9.89) for the 2019 ASF epidemics, and 2.00 (range: 0.06 – 11.10) for the 2020 ASF epidemics. In addition, the estimated mean R0 was 3.82 (range: 1.16 – 8.78) in winter, 1.39 (range: 0.16 – 6.30) in spring, 4.82 (range: 0.26 – 17.08) in summer, and 2.21 (range: 0.51 – 5.86) in fall. Even though the Korean government has applied ASF control measures, including hunting or fencing, the ASF epidemic situation in wild boars has intensified. For ASF control in wild boars, tailor-made hunting, wild boar management, or active searching for carcasses are required to reduce the ASF virus. For ASF prevention in domestic pigs, no contact between wild boars and domestic pigs and a biosecurity plan by veterinarians are needed to decrease the risk of ASF virus transmission from wild boars to domestic pigs.
Mesenchymal stem cells (MSCs) are multipotent cells capable of replicating as undifferentiated cells, and thus hold therapeutic implications in field of regenerative medicine and reproductive biotechnology. In the present study, we compared the stem cell properties of bovine ear skin tissue (ESK)- and nasal mucosa (NM)-derived MSCs. Bovine ESK-MSCs and NM-MSCs were successfully isolated by collagenase digestion and maintained proliferative capacity during the 20 consecutive passages. Both ESK-MSCs and NM-MSCs showed similar morphology and expressed common cell surface markers (CD29, CD44, CD90, and CD105). Also, we compared differentiation potentials of bovine ESK-MSCs and NM-MSCs into osteogenic, adipogenic, and chondrogenic lineages through specific staining and quantitative real-time RT-PCR. As results, bovine ESK-MSCs and NM-MSCs could differentiate into mesodermal cell lineages. However, bovine ESK-MSCs and NM-MSCs exhibited difference in expression of differentiation-related specific markers. Specifically, NM-MSCs exhibited increased expression levels of osteocalcin, peroxisome proliferator-activated receptor gamma, and aggrecan compared to ESK-MSCs. Also, ESK-MSCs exhibited increased expression levels of collagen type I, II, and lipoprotein lipase compared to NM-MSCs. We suggest that the nasal mucosa of bovine could be used as a source of bovine MSCs.
Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory disease in humans, with a case fatality rate of approximately 35%, thus posing a considerable threat to public health. A lack of approved vaccines or antivirals currently constitutes a barrier for controlling disease outbreaks and spread. In this study, we generated a replication-defective recombinant vesicular stomatitis virus expressing the MERS-CoV spike (S) protein (VSV/MERS). Uncleaved and cleaved S proteins were detected in VSV/MERS by western blotting. And VSV/MERS specifically transduced cells expressing human dipeptidyl peptidase 4, a receptor for MERS-CoV. To investigate the immunogenicity of VSV/MERS, mice were immunized intramuscularly with VSV/MERS and alum adjuvant. MERS-CoV S-specific IgG was detected in serum samples from immunized mice. These antibodies inhibited MERS entry in vitro, suggesting a protective efficacy of VSV/MERS immunity. The data demonstrate that VSV/MERS has potent immunogenicity and could serve as a novel potential vaccine platform for MERS in dromedary camels and human.
In this study, we investigated the antioxidant activity and anticancer effect of Coprinus comatus (C. comatus) extracts. Free radical scavenging capacity of the C. comatus extracts was evaluated in vitro by the DPPH assay. C. comatus exhibited the strong DPPH radical scavenging activity. In vitro tests were also performed to examine the anticancer activity of C. comatus against 293 human normal epithelial kidney cells and various human cancer cell lines including AGS, Hela and HCT-15. C. comatus extracts showed the potent cancer cell-selective growth inhibitory activity against AGS, Hela, and HCT-15 cells, but slightly inhibited 293 normal cell growth. We examined several biological activities such as antitumor effects of C. comatus extracts in vivo. Solid tumors were induced by Sarcoma-180 inoculation in the left groin of BALB/c mice and then C. comatus extracts were oral administered. After 5 weeks, all mice were sacrificed and their tumor weights were measured. C. comatus extracts exhibited the most effective antitumor activity, and the tumor growth rate was inhibited by 55% in comparison with control group. Taken together, these results indicate that C. comatus extracts showed high antioxidant activity and possessed powerful antitumor activity.
In this study, the near-complete genome sequence of the novel reassortant H1N2 influenza A virus strain A/swine/Korea/KS60/2016 is reported. Sequences of the hemagglutinin (HA), neuraminidase (NA), and polymerase basic 2 (PB2) genes were analyzed, revealing that the isolates contain segments from previous Korean swine H1N2 strains. Additionally, the remaining genes of this strain originated from human H1N1 strains in 2009.
Two dogs presented with nodular masses on the head and scapula. The masses recurred after excision and were submitted for histopathological examination. Macroscopically, hemorrhage and necrosis were apparent on the cut surface. Microscopically, the lesions were poorly demarcated and incorporated subcutaneous fat and adjacent skeletal muscle fibers. Fibrocytes and fibroblasts were admixed and haphazardly arranged. Both were diagnosed with nodular fasciitis (NF). NF has been rarely reported and called as a ‘pseudosarcomatous’ lesion because of its infiltrative growth and cellular pleomorphism. The present report describes unusual cases of recurrent NF in two young dogs based on histopathologic and clinical features.
Aspergillus flavus (A. flavus) and Aspergillus fumigatus (A. fumigatus) are the main fungi that cause stonebrood in honey bees. Additionally, these fungi cause the declines of honey bee population and the economic loss in the beekeeping industry. In this study, the efficacy of a disinfectant, composed to chlorine dioxide (10%, w/v) and quaternary ammonium compound (12.5%, w/v), was evaluated against A. flavus and A. fumigatus. A fungicidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test fungi for 30 min at 4°C. The disinfectant and test fungi were diluted with low and high organic matter (OM) suspension according to treatment condition. On low OM condition, the fungicidal activity of the disinfectant against A. flavus and A. fumigatus was all 2.0 fold dilutions. On high OM condition, the fungicidal activity of the disinfectant against A. flavus and A. fumigatus was all 1.25 fold dilutions. The recommended dilution ratio of the disinfectant in low and high OM was 1.6 and 1.0 fold dilution, respectively. As the disinfectant possesses fungicidal efficacy against A. flavus and A. fumigatus, the disinfectant can be used to prevent the stonebrood in honey bees.
Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae is a highly contagious disease that leads to enormous economic losses in pig industry, worldwide. Of the many virulence factors produced by the causative bacterium, ApxA exotoxins have been considered as the most important contributor to the disease. The toxins are classified into four different types; ApxIA, ApxIIA, ApxIIIA and ApxIVA. Uniquely, ApxIVA is expressed across all serotypes of A. pleuropneumoniae only during in vivo infection in pigs. Active research focusing on resolving the precious roles and mechanisms of the toxins is still at its primitive stage. In this study, we report the development of monoclonal antibodies against the two major antigenic epitopes that were characterized in our previous study incorporating the in silico predictions and protein modeling analyses. Recombinant proteins of the selected epitopes were expressed and purified after molecular cloning of the corresponding partial genes in E. coli expression system. Subsequently, we generated hybridomas with lymphoid cells from the rats immunized with the recombinantly expressed proteins of Apx. Consequently, hybridomas exhibiting strong productivity of the monoclonal antibodies were selected for downstream verifications that tested for reactivity and specificity using Western blot and ELISA. Our results strongly suggest the potential application of the monoclonal antibodies developed in this study as useful reagents to further elaborate the mechanism of the A. pleuropneumoniae infection in pig.