• Korean Journal of Veterinary Research
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• v.51 no.2
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• pp.123-128
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• 2011

Salmonella spp. is an important pathogen to both public and swine industry. The aim of this study was to investigate the distribution of Salmonella serovar and antibiotics susceptibility of the isolates from Korean swine producing systems. A total of 63 (5.28%) Salmonella spp. was isolated from 1,194 samples (977 fecal materials and 67 organ samples). The predominant Salmonella (S.) enterica serotype and serovar was group B (69.8%) and S. Typhimurium (47.6%), S. Derby (20.6%) and S. Heidelberg (1.6%). But S. Cholerasuis which is characterized host specific by septicemia and enteritis to pigs was not isolated. Antimicrobial susceptibility of the isolates varies as follows: Norfloxacine (75%), Ciprofloxacin (67.5%), Amikacin (60%), Colistin (60%), Enrofloxacin (55%). All of isolates were resistant to Erythromycin, Penicillin, Tetracycline and Lincomycin. The results of this study provided useful information regarding antimicrobial susceptibility and resistance patterns to treat salmonellosis and to prevent emergence of multidrug resistance Salmonella.

• Journal of Life Science
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• v.7 no.2
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• pp.79-87
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• 1997

To determine the cause of Vibrio septicemia by understanding the characteristics endotoxin from Vibrio vulnificus, lethal dose, heat resistance and vascular permeability enhancing activity were svaluated using vegestative cell and cell homogenate and the result is as follows: 1. Vibrio vulnificus CDC B3547 of patient origin did not exihibit any significant difference in toxicity compared to Vibrio vulnificus B57 of enviroment origin. 2. Strong toxicity was observed when viable cell count of Vibrio vulnificus CDC B3547 was more than 10$^{7}$/ml. 3. Toxicity of cell homogenate was completely inactivited upon geating at 80$^{\circ}$C for 20min. 4. Cell homogenate did not show hemolyic activity but was acknowleged to have cytotoxicity. 5. Major lethal toxin against mouse was existed in Vibrio vulnificus CDC B3547; however, separation of LPS and LPS-protein complex was not successful using the current technique.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.144-148
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• 1993

The present study was undertaken to compare the pharmacological activities of crude Lithospermi radix reported with the clinical uses in the oriental medicine. Crude Lithospermi radix uesd for the treatment of burn, eczema, blister, diuretic, scarlet fever and septicemia as antipyretic, antidotic and antiphlogistics. Therefore we tested the effects of Lithospermi radix water extract on the liver-protective activities in the rats. The results obtained from enzyme assay, measurement of serum and liver alanine. aspartate aminotransferase(ALT, AST) and lipid composition indicated that Lithospermi radix water extract showed significant liver-protective activities against benzo(a)pyrene-induced hepatotoxicity.

• Journal of fish pathology
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• v.34 no.2
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• pp.177-184
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• 2021

Vaccines based on single-cycle viruses that are replication-incompetent due to knockout of replication-related structural gene(s) are more immunogenic than inactivated or subunit vaccines and can be used as delivery vehicles for foreign antigens without concerns on the reverting to virulent forms. The aim of this study was to develop a delivery vehicle for nervous necrosis virus (NNV)-like particles (VLPs) using G gene deleted single-cycle VHSV (rVHSV-𝚫G). Recombinant single-cycle VHSVs carrying NNV capsid protein gene between N and P gene of rVHSV-𝚫G genome (rVHSV-𝚫G-NNV_Cap) were rescued by reverse genetic technology. The successful expression of NNV capsid protein in cells infected with rVHSV-𝚫G-NNV_Cap was demonstrated by Western blot analysis, and the production of NNV VLPs in infected cells was confirmed using an electron microscopy. The results suggest that single-cycle VHSVs can be used as a safe delivery vehicle for NNV VLPs, and can be extended to other pathogens for the development of prophylactic vaccines.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.3
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• pp.245-255
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• 2021

Necrotizing enterocolitis (NEC) is a disease with high morbidity and mortality that occurs mainly in premature born infants. The pathophysiologic mechanisms indicate that gastrointestinal dysbiosis is a major risk factor. We searched for relevant articles published in PubMed and Google Scholar in the English language up to October 2020. Articles were extracted using subject headings and keywords of interest to the topic. Interesting references in included articles were also considered. Network meta-analysis suggests the preventive efficacy of Bifidobacterium and Lactobacillus spp., but even more for mixtures of Bifidobacterium, Streptococcus, and Bifidobacterium, and Streptococcus spp. However, studies comparing face-to-face different strains are lacking. Moreover, differences in inclusion criteria, dosage strains, and primary outcomes in most trials are major obstacles to providing evidence-based conclusions. Although adverse effects have not been reported in clinical trials, case series of adverse outcomes, mainly septicemia, have been published. Consequently, systematic administration of probiotic bacteria to prevent NEC is still debated in literature. The risk-benefit ratio depends on the incidence of NEC in a neonatal intensive care unit, and evidence has shown that preventive measures excluding probiotic administration can result in a decrease in NEC.

• Journal of fish pathology
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• v.33 no.2
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• pp.171-175
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• 2020

We developed and subsequently characterized mouse monoclonal antibodies (mAbs) against marine birnavirus (MABV). Eight hybridoma clones secreting mAbs against MABV were established. All eight mAbs (8G6, 11C3, 15E3, 17H6, 32A6, 35A7, 38B5, and 47E3) were reacted with viral protein 3 of MABV in MABV-infected CHSE-214, whereas, no reactivity was observed in normal CHSE-214 by western blot analysis. Moreover, these eight mAbs were strongly reacted with MABV, and no cross-reactivity has been observed against other five fish viruses (hirame rhabdovirus, infectious hematopoietic necrosis virus, nervous necrosis virus, spring viraemia of carp virus, and viral hemorrhagic septicemia virus), although five mAb (11C3, 15E3, 17H6, 32A6, and 38B5) reacted with both MABV and infectious pancreatic necrosis virus by enzyme linked immunosorbent assay (ELISA). These results indicate that the mAbs can be of value in MABV detection.

• Journal of fish pathology
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• v.33 no.2
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• pp.103-109
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• 2020

In order to use nervous necrosis virus (NNV) virus-like particles (VLPs) as a delivery tool for heterologous antigens or plasmids, we attempted to produce red-spotted grouper nervous necrosis virus (RGNNV) VLPs displaying a partial region of viral hemorrhagic septicemia virus (VHSV) glycoprotein at the surface and VLPs that are harboring DNA vaccine plasmids within the VLP. A peptide encoding 105 amino acids of VHSV glycoprotein was genetically inserted in the loop region of NNV capsid gene, and VLPs expressing the partial part of VHSV glycoprotein were successfully produced. However, in the transmission electron microscope analysis, the shape and size of the partial VHSV glycoprotein-expressing NNV VLPs were irregular and variable, respectively, indicating that the normal assembly of capsid proteins was inhibited by the relatively long foreign peptide (105 aa) on the loop region. To encapsulate by simultaneous transformation with both NNV capsid gene expressing plasmids and DNA vaccine plasmids (having an eGFP expressing cassette under the CMV promoter), NNV VLPs containing plasmids were produced. The encapsulation of plasmids in the NNV VLPs was demonstrated by PCR and cells exposed to the VLPs encapsulating DNA vaccine plasmids showed fluorescence. These results suggest that the encapsulation of plasmids in NNV VLPs can be done with a simple one-step process, excluding the process of disassembly-reassembly of VLPs, and NNV VLPs can be used as a delivery tool for DNA vaccine vectors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.844-849
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• 2022

The pathogenic Vibrio genus denotes halophilic bacteria that are distributed in aquatic environments, including both sea and freshwater. V. cholerae, V. vulnificus, and V. parahaemolyticus are the main species that can be potent human pathogens and the leading cause of septicemia, wound infections, and seafood borne gastroenteritis. The aim of this study was to investigate the presence of pathogenic Vibrios in seawater. We obtained a total of 80 seawater samples from the Geum River estuary area in the west coast of Korea from April to December 2021. Pathogenic Vibrios was determined using a combination of the most probable number-polymerase chain reaction (MPN-PCR) methods. The detection levels of V. cholerae, V. parahaemolyticus, and V. vulnificus in the seawater samples were 7.5%, 68.8%, and 30.0%, respectively. The quantitative results were as follows: 3.6-3.6 MPN/100 mL in V. cholerae, 3.6-3,400 MPN/100 mL in V. parahaemolyticus, and 3.6-4,300 MPN/100 mL in V. vulnificus. Overall, these results provide novel insight into the necessity for seawater sanitation in the Geum River estuary area, and could help reduce the risk of seafood-borne outbreaks caused by pathogenic Vibrios.

• Journal of fish pathology
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• v.36 no.2
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• pp.389-394
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• 2023

Infectious hematopoietic necrosis virus (IHNV) is s significant viral pathogen affecting cultured rainbow trout (Oncorhynchus mykiss) in Korea. In this study, five monoclonal antibodies (mAbs) (IHNV-1, 2, 3, 4, and 5) were produced using purified IHNV. Reactivities of these mAbs were analyzed by western blot (WB), enzyme-linked immunosorbent assay (ELISA), and indirect fluorescent antibody test (IFAT). These mAbs recognized glycoprotein (69 kDa, IHNV-1), nucleocapsid protein (39 kDa, IHNV-3, 4, and 5), or phosphoprotein (27 kDa, IHNV-2) of IHNV by WB analysis. ELISA results indicated that these five mAbs were specific to IHNV without showing any cross-reactivity against other fish viruses (hirame rhabdovirus, infectious pancreatic necrosis virus, and viral hemorrhagic septicemia virus). IFAT demonstrated specific fluorescence signals of IHNV-infected epithelioma papulosum cyprini (EPC) cells, whereas no reactivity of normal EPC cells was observed. These mAbs can be very useful for immuno-diagnosis of IHNV infection.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.763-770
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• 1998

Salmonella typhimurium is a causitive agent of diarrhea, fever, gastroenteritis, septicemia and sudden death in piglet. The currently used methods such as IFA, ELISA, DNA hybridization assay is needed a long-time and difficult to detect the organism in carrier animal or contaminated sample with other agents. However, it is important to detect rapidly and sensitively S typhimurium in piglet with other infectious pathogens to minimize an economic loss. Two sets of PCR primer, rfbJ forward primer(5'-AGAATATGTAATTGTCAG-3') and reverse primer(5'-TAACCGTTTCAGTAGTTC-3') were designed to amplify a 882 by fragment of Salmonella serovar type B gene. The target genomic DNA for PCR was extracted from the cultivated materials with various enrichment periods in a nonselective enrichment agar and broth with clinical specimens. The PCR is carried out here made it possible to detect the gene from two hours. Also, the amplified fragment with PCR was cloned into pGEM-T vector and digested with restrict enzyme, and sequenced for the identification of Salmonella serotype B rfbJ gene. Duplicated cultivation agar-broth followed by PCR were performed to develop a rapid and sensitive detection of S typhlmurium based on serovar type. This duplicated cultivation-PCR method provides a sensitive and rapid diagnostic tool to detect Salmonella from infected piglet with improved sensitivity.