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Tenan, South Korea

Lee G.,National Veterinary Research and Quarantine Service | Han D.,Cheonan Yonam College | Song J.-Y.,National Veterinary Research and Quarantine Service | Kim J.-H.,Jeju National University | Yoon S.,National Veterinary Research and Quarantine Service
FEMS Immunology and Medical Microbiology

Swine hepatitis E virus (sHEV) has been discovered to be almost ubiquitous in pigs, and is antigenically and genetically related to human HEV. Proteomic analysis was used to identify altered protein expression in swine liver, using two-dimensional electrophoresis and peptide mass fingerprinting. A total of 10 protein spots exhibited significant alterations in the sHEV-infected organ. The upregulation of apolipoprotein E (Apo E) and downregulation of ferritin heavy chain were confirmed by Western analysis and by semi-quantitative reverse transcription-PCR. The elevated expression of Apo E may provide a novel insight into molecular responses to HEV infection in swine. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. Source

Jung B.-G.,Chonnam National University | Ko J.-H.,Chonnam National University | Cho S.-J.,Chonnam National University | Koh H.-B.,Chonnam National University | And 3 more authors.
Journal of Veterinary Medical Science

Maesil (Prunus mume) has long been used as a traditional drug and healthy food in East Asian countries. It possesses a number of beneficial biological activities including potential antimicrobial effects against pathogens. Probiotics also have antibacterial effects. Moreover, some probiotics have an important role in regulating the immune system. The present study evaluated the immune enhancing effects of fermented Msesil with probiotics (Saccharomyces cerevisiae, Bacillus subtilis and Lactobacillus acidophilus) in mice, especially against Bordetella bronchiseptica, as an initial step towards the development of feed supplements for the promotion of immune activity and prevention of disease, especially in pigs. Continuous ingestion of fermented Masesil with probiotics markedly increased the macrophage ratio in peripheral blood and the T lymphocyte ratio in the spleen. In addition, antibody production against formalin-killed B. bronchiseptica significantly increased in the mice fed fermented Maesil compared with the control group. The number of leukocytes was significantly higher in the bronchio-alveolar lavage obtained from the fermented Maesil-fed animals compared to it in the control group at day 3 (maximal peak time) after experimental B. bronchiseptica infection. Moreover, at 7 day post-infection, relative messenger RNA expression levels of tumor necrosis factor-α and interferon-γ were significantly increased in splenocytes of mice fed fermented Maesil compared with those in the control group. Taken together, these findings suggest that feed containing fermented Maesil with probiotics enhances immune activity in mice, especially against B. bronchiseptica, via the potent stimulation of non-specific immune responses. Source

Lee G.,National Veterinary Research and Quarantine Service NVRQS | Han D.,Cheonan Yonam College | Song J.-Y.,National Veterinary Research and Quarantine Service NVRQS | Lee Y.-S.,Seoul National University | And 3 more authors.
Journal of General Virology

Porcine circovirus type 2 (PCV2) is the main causative agent of porcine circovirus-associated disease, such as post-weaning multisystemic wasting syndrome, which involves lymphocyte depletion. However, little is known about the molecular mechanisms of lymphoid depletion. To gain insight into the interaction between virus and host cells, microarrays were used to analyse changes in genomic expression in lymph nodes following PCV2 infection of pigs, together with negative controls. Total RNA was subjected to microarray analysis with an Affymetrix Porcine Genome Array GeneChip. Of the 23 256 pig genes arrayed on a chip, 160 genes showed altered expression after infection (upregulated, 64; downregulated, 96). The altered genomic expression of 18 selected genes was confirmed by quantitative real-time PCR. The expression changes of numerous genes involved in innate immune defence (TLR1, CD14 and CD180), immunosuppressed responses (FGL2 and GPNMB), pro-inflammatory signals (galectin-3) and fasting processes (ANGPTL-4) indicate that PCV2 has developed an intricate mechanism to cause immunosuppression, inflammatory cell infiltration and weight loss in pigs. The results of this study provide a basis for understanding the molecular pathogenesis of PCV2 infection. © 2010 SGM. Source

Lee L.N.,Torrey Pines Institute for Molecular Studies | Lee L.N.,University of Oxford | Dias P.,Torrey Pines Institute for Molecular Studies | Han D.,Torrey Pines Institute for Molecular Studies | And 7 more authors.
American Journal of Pathology

Secondary bacterial infections that follow infection with influenza virus result in considerable morbidity and mortality in young children, the elderly, and immunocompromised individuals and may also significantly increase mortality in normal healthy adults during influenza pandemics. We herein describe a mouse model for investigating the interaction between influenza virus and the bacterium Haemophilus influenzae. Sequential infection with sublethal doses of influenza and H. influenzae resulted in synergy between the two pathogens and caused mortality in immunocompetent adult wild-type mice. Lethality was dependent on the interval between administration of the bacteria and virus, and bacterial growth was prolonged in the lungs of dual-infected mice, although influenza virus titers were unaffected. Dual infection induced severe damage to the airway epithelium and confluent pneumonia, similar to that observed in victims of the 1918 global influenza pandemic. Increased bronchial epithelial cell death was observed as early as 1 day after bacterial inoculation in the dual-infected mice. Studies using knockout mice indicated that lethality occurs via a mechanism that is not dependent on Fas, CCR2, CXCR3, interleukin-6, tumor necrosis factor, or Toll-like receptor-4 and does not require T or B cells. This model suggests that infection with virulent strains of influenza may predispose even immunocompetent individuals to severe illness on secondary infection with H. influenzae by a mechanism that involves innate immunity, but does not require tumor necrosis factor, interleukin-6, or signaling via Toll-like receptor-4. Copyright © American Society for Investigative Pathology. Source

Kwon S.,Seoul National University | Choi G.J.,Korea Research Institute of Chemical Technology | Kim K.S.,Seoul National University | Kwon H.J.,Cheonan Yonam College
Korean Journal of Horticultural Science and Technology

The present study was conducted to determine the effect of electron beam irradiation on control of Botrytis cinerea and postharvest quality of cut roses. Electron beam doses of 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 10, and 20 kGy were applied with a 10-MeV linear electron beam accelerator (EB Tech, Korea). Electron beams inhibited spore germination and mycelial growth of B. cinerea with increasing irradiation doses. Conidia of B. cinerea were more tolerant to irradiation than were mycelia: the effective irradiation doses for 50% inhibition (ED50) of spore germination and mycelial growth were 2.02 kGy and 0.89 kGy, respectively. In addition, electron beam irradiation was more effective in reducing mycelial growth of B. cinerea at 10°C than at 20°C. Analysis of in vivo antifungal activity revealed that elevated irradiation doses exhibited increased control efficacy for tomato gray mold. Flower longevity and fresh weight of cut roses decreased when the irradiation dose was increased. In addition, flower bud opening tended to be inhibited in a dose-dependent manner. Although ‘Decoration’, ‘Il se Bronze’, ‘Queen Bee’, and ‘Revue’ roses tolerated and maintained overall postharvest quality up to 0.4 kGy, ‘Vivian’ did not, demonstrating that the irradiation sensitivity of cut roses varies according to cultivar. Ⓒ 2014 Korean Society for Horticultural Science. Source

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