• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.575-581
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• 1995

Both immunoelectron microscopy(IEM) and immunogold conjugate immunoelectron microscopy (IGC-IEM) techniques were developed for the detection of porcine epidemic diarrhea virus(PEDV) from the feces. Fecal samples were incubated sequentially with anti-PEDV monoclonal antibody(MoAb) and immunogold conjugated goat anti-mouse IgG+IgM. Then negatively stained, mounted on the formvar carbon-coated copper EM grids and observed by the transmission electron microscope. By the direct electron microscopy(DEM), coronavirus particles were observed from 17 cases of total 33 fecal samples of grower pigs and sows. The virons of coronavirus were moderately pleomorphic but mostly spherical, with a diameter ranged from 90 to 190nm. PED virus particles were identified from 15 cases of 17 DEM positive samples by the IEM and IGC-IEM techniques. Aggregates of PED virus coated with specific antibody were seen in fecal samples incubated with homologous anti-PED virus MoAb but not in control samples incubated with anti-TGE virus MoAb. Following incubation with immunogold-conjugated secondary antibody, the gold granules were usually distributed around and among the virus particles and soluble and viral particle-associated antigen. So, IEM and IGC-IEM techniques were proved a rapid and sensitive methods for detection and identification of PED virus from fecal and intestinal contents.

• KSBB Journal
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• v.26 no.1
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• pp.62-68
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• 2011

To isolate Lactic acid bacteria for animals, we have screened from Kim-chi, swine intestine, swine feces, and dairy products by random selection and anti-viral, antipathogenic bacteria test. Among them, CLP-1 shown that inhibitory effect against rotavirus, porcine epidemic diarrhea (PED) virus, Salmonella sp, and E.coli. By examining biological property, API-ZYM and identified Lactobacillus plantarum by 16S rDNAgene sequence. CLP-1 determined resistance to low pH and bile salt. Futhermore, the cell body of CLP-1 adhered to the intestinal epithelium tissue of swine and Caco-2 cell. CLP-1 was examined on cell immune system modulating activity in vitro. The whole cell and cell culture supernatant was increasing of interferon-${\beta}$ activity. And then, CLP-1 increased prevention effect by Salmonella enteritidis infection in SPF chickens. And we determined similar result in pigs.

• Korean Journal of Veterinary Service
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• v.44 no.2
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• pp.73-83
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• 2021

Although many swine farms continuously vaccinated to sow to prevent Porcine epidemic diarrhea(PED), PED has occurred annually in swine herds in Jeonbuk province, Korea. In the present study, the small intestine and feces samples from 17 farms where severe watery diarrhea and death of newborn piglets occurred in 2019 were collected, amplified by RT-PCR and determined the complete nucleotide sequences of the spike (S) glycoprotein genes of nine Jeonbuk PEDV isolates. The spike (S) glycoprotein is an important determinant for molecular characterization and genetic relationship of PEDV. These nine complete S gene isolates were compared with other PEDV reference strains to identify the molecular diversity, phylogenetic relationships and antigenicity analysis. 9 field strains share 98.5~100% homologies with each other at the nucleotide sequence level and 97.3~100% homologies with each other at the amino acid level. The nine Jeonbuk PEDV isolates were classified into G2b group including a genetic specific signal, S-indels (insertion and deletion of S gene). In addition, comparisons the neutralizing epitopes of S gene between 9 field strains and domestic vaccine strains of Korea mutated 12-15 amino acids with SM-98-1 (G1a group) and mutated 0-3 amino acids with QIAP1401 (G2b group). Therefore, the development of G2b-based live vaccines will have to be expedited to ensure effective prevention of endemic PED in Korea. In addition, we will need to be prepared with periodic updates of preventive vaccines based on the PEDV variants for the re-emergence of a virulent strain.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.189-200
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• 2009

The purpose of this study was to evaluate the effect of a subsequent infection of PCV2 on piglets with PEDV. In clinical signs, the signs observed in dual-infected with PEDV and PCV2 piglets and alone infected with PEDV piglets ranged from diarrhoea to vomiting and dehydration. Dual-infected piglets developed signs of anorexia, vomiting and watery diarrhoea within 12 hpi. Nevertheless alone -infected piglets caused pasty diarrhea at first. In mortality, dual infections showed 25%, but alone -infections showed 8.3%, respectively. In gross findings, piglets dual-infected with PEDV and PCV2 appeared the severe findings of congestion, distension of lumen, milder curdes of undigested milk in stomach than those of single-infected piglets. In histopathological findings, piglets of dual-infection group appeared the more severe findings of villous atrophy and fusion, congesion, exfoliation, vacuolation, squamation, loss of cilia and proliferation of crypt. Significant (P<0.05) decrease in VH:CD ratio in dually infected piglets compared to piglets from alone-PEDV infections. In immunohistochemical findings, strong hybridization signals in dual-infected piglets observed moderate to severe villous atrophy or vacuolation with positive cells arranged continuously over the villi. In the lumen, exfoliated enterocytes were strongly positive in dual-infected piglets. A number of PEDV-positive cells in dual-infected pigs were significantly higher than that in alone PEDV-infected piglets.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.8
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• pp.1075-1082
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• 2016

Modern livestock production became highly intensive and large scaled to increase production efficiency. This production environment could add stressors affecting the health and growth of animals. Major stressors can include environment (air quality and temperature), nutrition, and infection. These stressors can reduce growth performance and alter immune systems at systemic and local levels including the gastrointestinal tract. Heat stress increases the permeability, oxidative stress, and inflammatory responses in the gut. Nutritional stress from fasting, antinutritional compounds, and toxins induces the leakage and destruction of the tight junction proteins in the gut. Fasting is shown to suppress pro-inflammatory cytokines, whereas deoxynivalenol increases the recruitment of intestinal pro-inflammatory cytokines and the level of lymphocytes in the gut. Pathogenic and viral infections such as Enterotoxigenic E. coli (ETEC) and porcine epidemic diarrhea virus can lead to loosening the intestinal epithelial barrier. On the other hand, supplementation of Lactobacillus or Saccharaomyces reduced infectious stress by ETEC. It was noted that major stressors altered the permeability of intestinal barriers and profiles of genes and proteins of pro-inflammatory cytokines and chemokines in mucosal system in pigs. However, it is not sufficient to fully explain the mechanism of the gut immune system in pigs under stress conditions. Correlation and interaction of gut and systemic immune system under major stressors should be better defined to overcome aforementioned obstacles.

• IMMUNE NETWORK
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• v.21 no.1
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• pp.11.1-11.10
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• 2021

Coronavirus causes an infectious disease in various species and crosses the species barriers leading to the outbreak of zoonotic diseases. Due to the respiratory diseases are mainly caused in humans and viruses are replicated and excreted through the respiratory tract, the nasal fluid and sputum are mainly used for diagnosis. Early diagnosis of coronavirus plays an important role in preventing its spread and is essential for quarantine policies. For rapid decision and prompt triage of infected host, the immunochromatographic assay (ICA) has been widely used for point of care testing. However, when the ICA is applied to an expectorated sputum in which antigens are present, the viscosity of sputum interferes with the migration of the antigens on the test strip. To overcome this limitation, it is necessary to use a mucolytic agent without affecting the antigens. In this study, we combined known mucolytic agents to lower the viscosity of sputum and applied that to alpha and beta coronavirus, porcine epidemic diarrhea virus (PEDV) and Middle East respiratory syndrome coronavirus (MERS-CoV), respectively, spiked in sputum to find optimal pretreatment conditions. The pretreatment method using tris(2-carboxyethyl)phosphine (TCEP) and BSA was suitable for ICA diagnosis of sputum samples spiked with PEDV and MERS-CoV. This sensitive assay for the detection of coronavirus in sputum provides an useful information for the diagnosis of pathogen in low respiratory tract.

• Food Science and Preservation
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• v.15 no.6
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• pp.891-896
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• 2008

Total phenolics and flavonoids, and the antioxidant capacity of plum cultivar wines (Prunus salicina L. cv. Soldam and P. salicina L. cv. Formosa) were determined using spectrophotometric methods. The total phenolic and flavanoid contents of Soldam wine were $478.4\;{\pm}\;5.6\;mg$ GAE and $202.4\;{\pm}\;7.5\;mg$ CE per L,respectively, and in Formosa wine were $200.6\;{\pm}\;7.5\;mg$ GAE and $64.4\;{\pm}\;6.8\;mg$ CE per L, respectively. Neutral and acidic phenolics in Soldam wine were extracted with ethyl acetate and 0.01 N HCl, respectively. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, neutral phenolics (64.5 EDA%) had $3{\sim}4$ times higher antioxidant activity than acidic phenolics (21.5 EDA%) and other related phenolic compounds such as chlorogenic acid (15.5 EDA%) and quercetin (24.6 EDA%) at a concentration of $100\;{\mu}g/mL$. The antiviral activities of neutral and acidic phenolics in Soldam wine were investigated in vitro using a virus-induced cytopathic effect (CPE) inhibition assay. Results showed that neutral and acidic phenolics at concentrations of $100\;{\mu}g/mL$ inhibited porcine epidemic diarrhea virus (PEDV) replication at rates of 78.12% and 58.37%, respectively. The inhibition rate of 10 g/mL neutral phenolics (69.42%) was higher than that of ribavirin as an antiviral reagent (57.86%). At concentrations of $100\;{\mu}g/mL$ or less, neutral and acidic phenolics of Soldam wine had no cytotoxic effect against vero cells.