27 results on '"Kyuhyung Choi"'
Search Results
2. A Systematic Review of Chromogranin a (CGA) and its Biomedical Applications, Unveiling its Structure-Related Functions
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Seung Joong Kim, Kyuhyung Choi, and Manhyuk Han
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010302 applied physics ,endocrine system ,biology ,Chemistry ,Translational medicine ,Biophysics ,General Physics and Astronomy ,Granin ,Chromogranin A ,02 engineering and technology ,Computational biology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Pancreastatin ,Biomarker (cell) ,0103 physical sciences ,biology.protein ,Bovine adrenal ,0210 nano-technology - Abstract
Chromogranin A (CgA), which is an intrinsically disordered protein that belongs to the granin family, was first discovered in the bovine adrenal medulla, and later identified in various organs. Under certain physiological conditions, CgA is cleaved into functionally diverse peptides, such as vasostatin-1, pancreastatin, and catestatin. In this review, we first describe the historical and systematic challenges for elucidating the molecular structures of CgA and its derived peptides and give a perspective of utilizing emerging techniques through integrative approaches. Subsequently, we review specific biological processes associated with CgA and its derived peptides in the neuroendocrine, immune, and digestive systems. Finally, we discuss biomedical applications of CgA as a biomarker, suggesting future directions toward translational and precision medicine.
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- 2020
3. Evaluation of a 20 year old porcine reproductive and respiratory syndrome (PRRS) modified live vaccine (Ingelvac ® PRRS MLV) against two recent type 2 PRRS virus isolates in South Korea
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Chanhee Chae, Ikjae Kang, Jiwoon Jeong, Kyuhyung Choi, and Changhoon Park
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Gene Expression Regulation, Viral ,0301 basic medicine ,Swine ,viruses ,animal diseases ,030106 microbiology ,Porcine Reproductive and Respiratory Syndrome ,Viremia ,Biology ,Microbiology ,Virus ,03 medical and health sciences ,Immune system ,Viral Envelope Proteins ,Antigen ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,Phylogeny ,Attenuated vaccine ,General Veterinary ,virus diseases ,Viral Vaccines ,General Medicine ,respiratory system ,Vaccine efficacy ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,medicine.disease ,Virology ,Vaccination ,030104 developmental biology ,RNA, Viral - Abstract
Type 2 porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) was first isolated in Korea in 1994. The commercial PRRS modified live vaccine (Ingelvac® PRRS MLV, Boehringer Ingelheim Vetmedica Inc., St. Joseph, Missouri, USA) based on type 2 PRRSV, was first licensed for use in 3- to 18-week-old pigs in Korea in 1996. The objective of the present study was to evaluate the efficacy of this 20 year old commercial PRRS modified live vaccine (MLV) against two recent PRRSV isolates. Two genetically distant type 2 PRRSV strains (SNUVR150004 for lineage 1 and SNUVR150324 for lineage 5), isolated in 2015, were used as challenge virus. Regardless of the challenge virus, vaccination of pigs effectively reduced the level of viremia, the lung lesions, and of the PRRSV antigen within the lung lesions. The induction of virus-specific interferon-γ secreting cells by the PRRS vaccine produced a protective immune response, leading to the reduction of PRRSV viremia. There were no significant differences in efficacy against the two recently isolated viruses by the PRRS MLV based on virological results, immunological responses, and pathological outcomes. This study demonstrates that the PRRS MLV used in this study is still effective against recently isolated heterologous type 2 PRRSV strains even after 20 years of use in over 35 million pigs
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- 2016
4. In-situ Hybridization for the Detection of Sacbrood Virus in Infected Larvae of the Honey Bee (Apis cerana)
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H.S. Kang, M.-S. Yoo, B.-S. Yoon, H.-Y. Lim, Jiwoon Jeong, C. Chae, Kyuhyung Choi, Y.-H. Kim, Changhoon Park, S.-W. Kang, and I. Kang
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0106 biological sciences ,0301 basic medicine ,Picornaviridae ,In situ hybridization ,Polymerase Chain Reaction ,01 natural sciences ,Genome ,Pathology and Forensic Medicine ,law.invention ,03 medical and health sciences ,law ,Complementary DNA ,Animals ,In Situ Hybridization ,Apis cerana ,Polymerase chain reaction ,Larva ,Picornaviridae Infections ,General Veterinary ,biology ,fungi ,Sacbrood virus ,Honey bee ,Bees ,biology.organism_classification ,Virology ,010602 entomology ,030104 developmental biology - Abstract
The aim of this study was to develop and use in-situ hybridization (ISH) for the detection and localization of the sacbrood virus (SBV) in Korean honey bee (Apis cerana) larvae that were infected naturally with SBV. A 258 base pair cDNA probe for SBV was generated by polymerase chain reaction. Cells positive for viral genome typically showed a dark brown reaction in the cytoplasm. SBV was detected consistently in trophocytes and urocytes. The ISH was successfully applied to routinely fixed and processed tissues and thus should prove helpful in the diagnosis and characterization of viral distribution in infected larvae.
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- 2016
5. Differential Expression of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Open Reading Frame 5, but not Apoptogenic Cytokines, Contribute to Severe Respiratory Disease in Pigs Infected with Type 2 PRRSV Compared with Pigs Infected with Type 1 PRRSV
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Jiwoon Jeong, Kyuhyung Choi, Changhoon Park, C. Chae, K. Han, I. Kang, J. Lee, and S.-J. Park
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0301 basic medicine ,Necrosis ,Genotype ,Swine ,040301 veterinary sciences ,viruses ,animal diseases ,medicine.medical_treatment ,Porcine Reproductive and Respiratory Syndrome ,Virulence ,Apoptosis ,Biology ,Real-Time Polymerase Chain Reaction ,Pathology and Forensic Medicine ,0403 veterinary science ,Open Reading Frames ,03 medical and health sciences ,In Situ Nick-End Labeling ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,Lung ,General Veterinary ,Respiratory disease ,virus diseases ,04 agricultural and veterinary sciences ,respiratory system ,medicine.disease ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Immunohistochemistry ,Virology ,030104 developmental biology ,medicine.anatomical_structure ,Cytokine ,Real-time polymerase chain reaction ,Immunology ,Cytokines ,medicine.symptom - Abstract
The aim of this study was to compare the expression of open reading frame 5 (ORF5) of porcine reproductive and respiratory syndrome virus (PRRSV) and apoptogenic cytokines in the lungs from pigs infected with type 1 and type 2 PRRSV. Microscopical lung lesion scores and the mean number of apoptotic cells were significantly (P
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- 2016
6. Efficacy of a new bivalent vaccine of porcine circovirus type 2 and Mycoplasma hyopneumoniae (Fostera™ PCV MH) under experimental conditions
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Kyuhyung Choi, Chanhee Chae, Changhoon Park, and Jiwoon Jeong
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0301 basic medicine ,Swine ,animal diseases ,Antibodies, Viral ,medicine.disease_cause ,0403 veterinary science ,Random Allocation ,Mycoplasma hyopneumoniae ,Medicine ,Porcine circovirus associated disease ,Lung ,Bacterial Shedding ,Swine Diseases ,biology ,Viral Vaccine ,virus diseases ,04 agricultural and veterinary sciences ,Bacterial vaccine ,Vaccination ,Porcine circovirus ,Treatment Outcome ,Infectious Diseases ,Bacterial Vaccines ,Molecular Medicine ,Animal Experimentation ,Circovirus ,040301 veterinary sciences ,Injections, Intramuscular ,Interferon-gamma ,03 medical and health sciences ,Animals ,Mycoplasma Infections ,Vaccines, Combined ,Viremia ,Circoviridae Infections ,General Veterinary ,General Immunology and Microbiology ,business.industry ,Public Health, Environmental and Occupational Health ,Viral Vaccines ,Mycoplasma ,biology.organism_classification ,Antibodies, Neutralizing ,Virology ,030104 developmental biology ,Immunology ,Leukocytes, Mononuclear ,Lymph Nodes ,business - Abstract
The objective of this study was to evaluate the efficacy of a new bivalent vaccine (Fostera™ PCV MH, Zoetis) of porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae in growing pigs under experimental conditions. A total of 80 pigs were randomly divided into 8 groups (10 pigs per group). The pigs were administered the bivalent vaccine intramuscularly as a 2.0 mL dose at 21 days of age based on the manufacturer's instructions. Three weeks after vaccination, the pigs were inoculated with either PCV2 (intranasal route) or M. hyopneumoniae (intratracheal route) or both. Regardless of the type of inoculation, vaccinated pigs after challenge exhibited effective reduction of clinical signs, PCV2 viremia levels and mycoplasma nasal shedding, and lung and lymphoid lesion when compared to unvaccinated challenged pigs. Vaccinated challenged pigs had significantly higher (P
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- 2016
7. Concurrent vaccination of pigs with type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) protects against type 1 PRRSV but not against type 2 PRRSV on dually challenged pigs
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Ikjae Kang, Kyuhyung Choi, Changhoon Park, Jiwoon Jeong, Chanhee Chae, and Su-Jin Park
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Swine ,viruses ,animal diseases ,Porcine Reproductive and Respiratory Syndrome ,Heterologous ,Viremia ,Antibodies, Viral ,Interferon-gamma ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,Interferon gamma ,General Veterinary ,biology ,Viral Vaccine ,Vaccination ,virus diseases ,Viral Vaccines ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,medicine.disease ,Antibodies, Neutralizing ,Virology ,Titer ,Immunology ,biology.protein ,Antibody ,medicine.drug - Abstract
The objective of the present study was to evaluate the effect of concurrent vaccination of pigs with both type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) vaccine against heterologous dual challenge of both genotypes and compare with single vaccination of pigs against heterologous single challenge of both genotypes. Pigs were administered both type 1 and type 2 PRRSV vaccine concurrently into separate anatomical sites at 28 days of age and inoculated intranasally with both genotypes at 63 days of age. Neutralizing antibodies (NA) were not detected in any pigs in any group (NA titer
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- 2015
8. Nucleotide sequence analysis of Vietnamese highly pathogenic porcine reproductive and respiratory syndrome virus from 2013 to 2014 based on the NSP2 and ORF5 coding regions
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Kyuhyung Choi, Jiwoon Jeong, Changhoon Park, Duy Tien Do, Toan Tat Nguyen, Chanhee Chae, Khoa Minh Vo, and Dung Thi Hanh Le
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Genetic Markers ,0301 basic medicine ,Swine ,Sequence analysis ,animal diseases ,viruses ,Vietnamese ,Molecular Sequence Data ,Porcine Reproductive and Respiratory Syndrome ,Sequence Homology ,Viral Nonstructural Proteins ,Arginine ,Evolution, Molecular ,03 medical and health sciences ,Viral Envelope Proteins ,Virology ,Animals ,Cluster Analysis ,Coding region ,Porcine respiratory and reproductive syndrome virus ,Gene ,Phylogeny ,Sequence Deletion ,Genetics ,biology ,Nucleic acid sequence ,virus diseases ,Sequence Analysis, DNA ,General Medicine ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,language.human_language ,Open reading frame ,030104 developmental biology ,Vietnam ,Genetic marker ,language ,RNA, Viral - Abstract
A total of 34 highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) strains isolated from Vietnam during 2013-2014 were sequenced and analyzed. A partial sequence of ORF1a corresponding to the nonstructural protein 2 (Nsp2) coding region and the full sequence of open reading frame 5 (ORF5) gene was used for the analysis. The HP-PRRSV strains were isolated from pig herds that had never been vaccinated for PRRSV. Nucleotide sequence identities in the portions of ORF1a corresponding to the nonstructural protein 2 (Nsp2) coding region and ORF5 ranged from 96.4 to 100 % and 83.2 to 100 %, respectively. All of the 34 Vietnamese HP-PRRSV strains showed two discontinuous 30-amino-acid deletions in the Nsp2 coding region as a genetic marker of prototypic Chinese HP-PRRSV. The amino acid arginine (R) was present at positions 13 and 151 in ORF5 in 29 out of 34 Vietnamese HP-PRRSV isolates, as well as in the prototypic Chinese HP-PRRSV. Sequence analysis of the ORF5 genes of all Vietnamese HP-PRRSVs revealed six subgroups: Viet 1 to 4, JAX1-like, and VR-2332-like. Nucleotide and amino acid sequence analysis of 34 Vietnamese HP-PRRSV isolates from 2013-2014 indicated that Vietnamese HP-PRRSV has undergone rapid evolutionary changes in recent years when compared with Vietnamese HP-PRRSV isolated before 2012.
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- 2015
9. Inhibition Of In Vitro Growth Of Porcine Enterotoxigenic And Shiga Toxin-Producing Escherichia Coli By Lactobacillus Plantarum Strains
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Sunghoon Kim, Jiwoon Jeong, Jae Chul Lee, Chanhee Chae, Kyuhyung Choi, Changhoon Park, and Oh Sung Kwon
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General Veterinary ,medicine.drug_class ,Veterinary medicine ,Antibiotics ,Drug resistance ,Enterotoxin ,Biology ,biology.organism_classification ,medicine.disease_cause ,bacterial infections and mycoses ,lactobacillus plantarum ,In vitro ,law.invention ,Microbiology ,fluids and secretions ,law ,Enterotoxigenic Escherichia coli ,SF600-1100 ,medicine ,Heat-stable enterotoxin ,bacteria ,in vitro growth inhibition ,escherichia coli ,Polymerase chain reaction ,Lactobacillus plantarum - Abstract
The objective of this study was to assess cell-free fermented culture broth of 9 Lactobacillus plantarum strains as antibiotic alternatives for the inhibition of in vitro growth of enterotoxigenic Escherichia coli (ETEC) and Shiga toxin-producing E. coli (STEC) isolated from postweaning pigs with colibacillosis and edema disease in 2014. A total of 10 ETEC and 5 STEC strains isolated from postweaning pigs were tested in antimicrobial susceptibility tests. ETEC and STEC strains used in this study possessed at least one of fimbrial, enterotoxin, and Shiga-toxin genes when tested by polymerase chain reaction. Among 9 L. plantarum strains tested, 3 strains (Lp 2-05, 2-06, and 1-03) showed inhibitory activity of in vitro growth against 10 ETEC strains (100%) and 7 strains (Lp 6-13, 3-06, 3-05, 7-01, 2-06, 1-03, and 6-05) showed inhibitory activity of in vitro growth against 5 STEC strains (100%). Three strains (Lp 3-05, 2-06, and 1-03) showed inhibitory activity of in vitro growth against 10 ETEC (100%) and 5 STEC (100%) strains. The results of this study show the inhibitory activity of cell-free fermented culture broth of L. plantarum against ETEC and STEC isolated from postweaning pigs with colibacillosis and edema disease.
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- 2015
10. Comparison of two genetically distant type 2 porcine reproductive and respiratory syndrome virus (PRRSV) modified live vaccines against Vietnamese highly pathogenic PRRSV
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Toan Tat Nguyen, Dai Tan Vo, Khang Duong Nguyen, Kyuhyung Choi, Changhoon Park, Duy Tien Do, Chanhee Chae, and Jiwoon Jeong
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Swine ,viruses ,animal diseases ,Molecular Sequence Data ,Sus scrofa ,Porcine Reproductive and Respiratory Syndrome ,Viremia ,Biology ,Real-Time Polymerase Chain Reaction ,Vaccines, Attenuated ,Microbiology ,Interferon-gamma ,Antigen ,medicine ,Animals ,Cluster Analysis ,Porcine respiratory and reproductive syndrome virus ,Interferon gamma ,Phylogeny ,Attenuated vaccine ,Base Sequence ,General Veterinary ,Viral Vaccine ,Vaccination ,virus diseases ,Viral Vaccines ,General Medicine ,respiratory system ,medicine.disease ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,Vietnam ,Immunology ,Sequence Alignment ,Viral load ,medicine.drug - Abstract
Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) known as pig high fever disease was first reported in China and has spread rapidly in neighboring southeastern Asian countries. The objective of this study was to evaluate the efficacy of a new type 2 PRRSV modified live vaccine (vaccine A) against a challenge with a HP-PRRSV and to compare the efficacy of two genetically distant type 2 PRRSV modified vaccines (vaccine A for lineage 8 and vaccine B for lineage 5) against HP-PRRSV (lineage 8) challenge. Pigs were divided into 4 groups (n=12/group); vaccinated challenged (2 groups), unvaccinated challenged, and unvaccinated unchallenged groups. Regardless of vaccines, vaccinated challenged pigs showed significantly lower (P
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- 2015
11. Comparison of Two Commercial Type 1 Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Modified Live Vaccines against Heterologous Type 1 and Type 2 PRRSV Challenge in Growing Pigs
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Su-Jin Park, Taeyeon Kim, Chanhee Chae, Kyuhyung Choi, Changhoon Park, Jiwoon Jeong, and Ikjae Kang
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Microbiology (medical) ,Swine ,Cross Protection ,viruses ,animal diseases ,Clinical Biochemistry ,Immunology ,Porcine Reproductive and Respiratory Syndrome ,Heterologous ,Viremia ,Vaccines, Attenuated ,Interferon-gamma ,Interferon ,medicine ,Animals ,Immunology and Allergy ,Porcine respiratory and reproductive syndrome virus ,Interferon gamma ,Lung ,Vaccines ,Vaccines, Synthetic ,biology ,Viral Vaccine ,virus diseases ,Viral Vaccines ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,medicine.disease ,Virology ,Interleukin-10 ,Vaccination ,Interleukin 10 ,Leukocytes, Mononuclear ,medicine.drug - Abstract
The objective of the present study was to compare the efficacy of two commercial type 1 porcine reproductive and respiratory syndrome virus (PRRSV) modified live vaccines against heterologous type 1 and type 2 PRRSV challenge in growing pigs. Vaccination with a type 1 PRRSV vaccine reduced the level of viremia after type 1 PRRSV challenge but did not reduce the level of viremia after the type 2 PRRSV challenge in pigs. Increased levels of interleukin-10 (IL-10) stimulated by type 2 PRRSV coincided with the low numbers of type 2 PRRSV-specific interferon gamma-secreting cells (IFN-γ-SC) in vaccinated pigs after type 2 PRRSV challenge, whereas low levels of IL-10 stimulated by type 1 PRRSV coincided with high numbers of type 1 PRRSV-specific IFN-γ-SC in vaccinated pigs after type 1 PRRSV challenge. Additionally, vaccination with the type 1 PRRSV vaccine effectively reduced the lung lesions and type 1 PRRSV nucleic acids in type 1 PRRSV-challenged pigs but did not reduce lung lesions and type 2 PRRSV nucleic acids in type 2 PRRSV-challenged pigs. There were no significant differences between two commercial type 1 PRRSV vaccines against type 1 and type 2 PRRSV challenge based on virological results, immunological responses, and pathological outcomes. This study demonstrates that vaccinating pigs with the type 1 PRRSV vaccine provides partial protection against respiratory disease with heterologous type 1 PRRSV challenge but no protection with heterologous type 2 PRRSV challenge.
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- 2015
12. Cross-protection of a new type 2 porcine reproductive and respiratory syndrome virus (PRRSV) modified live vaccine (Fostera PRRS) against heterologous type 1 PRRSV challenge in growing pigs
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Jiwoon Jeong, Kyuhyung Choi, Chanhee Chae, and Changhoon Park
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Swine ,Cross Protection ,viruses ,animal diseases ,Sus scrofa ,Porcine Reproductive and Respiratory Syndrome ,Heterologous ,Viremia ,Biology ,Antibodies, Viral ,Vaccines, Attenuated ,Microbiology ,Interferon-gamma ,Antigen ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,Respiratory system ,Attenuated vaccine ,Lung ,General Veterinary ,Vaccination ,virus diseases ,Viral Vaccines ,General Medicine ,respiratory system ,medicine.disease ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,Interleukin-10 ,medicine.anatomical_structure ,Immunology - Abstract
The objective of the present study was to determine the cross-protection of a new type 2 porcine reproductive and respiratory syndrome virus (PRRSV) modified live vaccine against heterologous type 1 PRRSV challenge in growing pigs. The mean rectal temperature and respiratory score was significantly (P
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- 2015
13. Comparison of the Pathogenesis of Single or Dual Infections with Type 1 and Type 2 Porcine Reproductive and Respiratory Syndrome Virus
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Changhoon Park, Jiwoon Jeong, Chanhee Chae, J. Lee, and Kyuhyung Choi
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Lung ,General Veterinary ,biology ,Swine ,Inoculation ,viruses ,animal diseases ,Porcine Reproductive and Respiratory Syndrome ,virus diseases ,Virulence ,respiratory system ,Clinical disease ,Pathogenicity ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,Virus ,Pathology and Forensic Medicine ,Pathogenesis ,medicine.anatomical_structure ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus - Abstract
The aim of this study was to compare the pathogenicity of single or dual infections with type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) in pigs. Pigs were inoculated intranasally with type 1 or type 2 PRRSV or both viruses together. Pigs infected with type 1 and type 2 PRRSV together had significantly (P
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- 2015
14. Comparison of pathogenicity of highly pathogenic porcine reproductive and respiratory syndrome virus between wild and domestic pigs
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T. D. Do, Jiwoon Jeong, Kyuhyung Choi, M. K. Vo, Changhoon Park, Chanhee Chae, and T. T. Nguyen
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Swine ,viruses ,animal diseases ,Porcine Reproductive and Respiratory Syndrome ,Animals, Wild ,Biology ,Pathogenesis ,Immune system ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,Lung ,Pathological ,General Veterinary ,Inoculation ,Stomach ,Antibody titer ,virus diseases ,General Medicine ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,medicine.anatomical_structure ,Animals, Domestic ,biology.protein ,Antibody - Abstract
The objective of this study was to compare the pathogenicity of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) infection between wild and domestic pigs based on clinical, immunological, and pathological evaluation. Upon challenge with HP-PRRSV, five wild pigs died compared to none of the domestic. Anti-PRRSV antibody titers were significantly (P < 0.05) higher in wild HP-PRRSV-infected pigs versus the domestic HP-PRRSV-infected pigs at 21 days post inoculation (dpi). Lung lesion scores at 7 dpi were also significantly (P < 0.01) higher in domestic infected pigs than wild infected pigs. The most striking difference was the viral tissue distribution between the wild and domestic HP-PRRSV-infected pigs. HP-PRRSV-positive cells were observed in bronchiolar, gastric, and renal tubular epithelial cells from wild HP-PRRSV-infected pigs only. The results in this study demonstrated a genetic difference exists between wild and domestic pigs, which could results in different clinical signs, immunological responses, and pathological outcomes to HP-PRRSV infection.
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- 2015
15. A New Modified Live Porcine Reproductive and Respiratory Syndrome Vaccine Improves Growth Performance in Pigs under Field Conditions
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Kyuhyung Choi, Jiwoon Jeong, Changhoon Park, Chanhee Chae, Ikjae Kang, and Hwi Won Seo
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Microbiology (medical) ,Veterinary medicine ,Swine ,animal diseases ,Molecular Sequence Data ,Clinical Biochemistry ,Immunology ,Porcine Reproductive and Respiratory Syndrome ,Biology ,Vaccines, Attenuated ,Body weight ,Viral genetics ,Republic of Korea ,medicine ,Animals ,Immunology and Allergy ,Porcine respiratory and reproductive syndrome virus ,Respiratory system ,Lung ,Survival analysis ,Microscopy ,Vaccines ,Histocytochemistry ,Viral Vaccine ,Body Weight ,Viral Vaccines ,Sequence Analysis, DNA ,Survival Analysis ,Vaccination ,Treatment Outcome ,medicine.anatomical_structure ,RNA, Viral ,Field conditions - Abstract
The change in growth performance resulting from a new modified live porcine reproductive and respiratory syndrome (PRRS) vaccine was evaluated under field conditions for registration with the government as guided by the Republic of Korea's Animal and Plant Quarantine Agency. Three farms were selected based on their history of PRRS-associated respiratory diseases. On each farm, a total of 45 3-week-old pigs were randomly allocated to one of two treatment groups, (i) vaccinated (n= 25) or (ii) control (n= 20) animals. A new modified live PRRSV vaccine increased market weight by 1.26 kg/pig (104.71 kg versus 103.45 kg;P< 0.05) and decreased mortality by 17% (1.33% versus 18.33%;P< 0.05). Pathological examination indicated that vaccination effectively reduced microscopic lung lesions compared with control animals on the 3 farms. Thus, the new modified live PRRS vaccine improved growth performance and decreased mortality and lung lesions when evaluated under field conditions.
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- 2014
16. Development of porcine circovirus 2 (PCV2) open reading frame 2 DNA vaccine with different adjuvants and comparison with commercial PCV2 subunit vaccine in an experimental challenge
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Changhoon, Park, Jiwoon, Jeong, Kyuhyung, Choi, Su-Jin, Park, Ikjae, Kang, and Chanhee, Chae
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Circovirus ,Swine Diseases ,Immunity, Cellular ,Swine ,animal diseases ,virus diseases ,Viral Vaccines ,Antibodies, Viral ,Antibodies, Neutralizing ,Article ,Interferon-gamma ,Open Reading Frames ,DNA, Viral ,Vaccines, DNA ,Animals ,Plasmids - Abstract
The objective of this study was to compare the protection against challenge with porcine circovirus 2 (PCV2) induced by an experimental vaccine based on open reading frame (ORF) 2 of PCV2 DNA plus an adjuvant (aluminum hydroxide, cobalt oxide, or liposome) and a commercial PCV2 subunit vaccine. A total of 35 colostrum-fed, cross-bred, conventional piglets were randomly divided into 7 groups. The commercial vaccine was more efficacious against PCV2 challenge than the 4 experimental vaccines according to immunologic, virologic, and pathological outcomes. The pigs inoculated with the experimental vaccine containing the liposome adjuvant had significantly higher levels (L’objectif de la présente étude était de comparer la protection contre une infection défi avec le circovirus porcin de type (CVP2) induite par un vaccin expérimental à base du cadre de lecture ouvert (ORF) 2 de l’ADN de CVP2 plus un adjuvant (hydroxyde d’aluminium, oxyde de cobalt, ou liposome) et un vaccin CVP2 sous-unitaire commercial. Un total de 35 porcelets croisés, conventionnels et nourris au colostrum ont été séparés de manière aléatoire en sept groupes. Le vaccin commercial était plus efficace contre l’infection par CVP2 que les quatre vaccins expérimentaux en fonction des résultats immunologiques, virologiques, et pathologiques. Les porcs inoculés avec le vaccin expérimental contenant l’adjuvant liposome avaient des titres significativement (
- Published
- 2016
17. Comparison of protection provided by type 1 and type 2 porcine reproductive and respiratory syndrome field viruses against homologous and heterologous challenge
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Chanhee Chae, Jiwoon Jeong, Kyuhyung Choi, and Changhoon Park
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0301 basic medicine ,040301 veterinary sciences ,Swine ,viruses ,animal diseases ,Cross Protection ,Porcine Reproductive and Respiratory Syndrome ,Heterologous ,Viremia ,Biology ,Antibodies, Viral ,Microbiology ,0403 veterinary science ,03 medical and health sciences ,Tissue culture ,Random Allocation ,Genotype ,medicine ,Homologous chromosome ,Animals ,Porcine respiratory and reproductive syndrome virus ,Lung ,General Veterinary ,virus diseases ,04 agricultural and veterinary sciences ,General Medicine ,respiratory system ,medicine.disease ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,Antibodies, Neutralizing ,030104 developmental biology ,Immunization ,biology.protein ,Antibody - Abstract
The objective of this study was to compare protection provided by type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) against homologous and heterologous challenge based on clinical, virological, immunological, and pathological analysis. At 3 and 8 weeks of age, pigs were inoculated intranasally with either 3 mL of tissue culture fluid containing 10 5 TCID 50 /mL of type 1 PRRSV or 3 mL of tissue culture fluid containing 10 5 TCID 50 /mL of type 2 PRRSV. The homologous challenges resulted in a significant boost of the neutralizing antibodies (NA) and interferon-γ secreting cells (IFN-γ-SC) compared to heterologous challenges. The reduction of secondary challenging PRRSV viremia coincided with the appearance of homologous PRRSV-specific NA and IFN-γ-SC. Homologous challenge reduced the severity of lung lesions and levels of PRRSV viremia significantly in pigs in comparison with heterologous challenge. The differences in homologous and heterologous NA and IFN-γ-SC response may explain the differences in protection against homologous and heterologous challenge between type 1 and type 2 PRRSV. Primary challenge (immunization) with type 1 PRRSV provided protection against the secondary homologous challenge with type 1 PRRSV but failed to provide protection against the secondary heterologous challenge of type 2 PRRSV. Primary challenge with type 2 PRRSV provided protection against both the secondary homologous challenge with type 2 PRRSV and the secondary heterologous challenge with type 1 PRRSV.
- Published
- 2016
18. A new single-dose bivalent vaccine of porcine circovirus type 2 and Mycoplasma hyopneumoniae elicits protective immunity and improves growth performance under field conditions
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Kyuhyung Choi, Changhoon Park, Jiwoon Jeong, and Chanhee Chae
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0301 basic medicine ,Circovirus ,040301 veterinary sciences ,Swine ,animal diseases ,Sus scrofa ,Microbiology ,0403 veterinary science ,03 medical and health sciences ,Mycoplasma hyopneumoniae ,medicine ,Animals ,Vaccines, Combined ,Circoviridae Infections ,Swine Diseases ,General Veterinary ,biology ,Coinfection ,Viral Vaccine ,Vaccination ,Viral Vaccines ,04 agricultural and veterinary sciences ,General Medicine ,Pneumonia of Swine, Mycoplasmal ,biology.organism_classification ,medicine.disease ,Virology ,Bacterial vaccine ,Porcine circovirus ,030104 developmental biology ,Immunology ,Bacterial Vaccines ,biology.protein ,Female ,Antibody - Abstract
The efficacy of the new single-dose bivalent vaccine of porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae was evaluated under field conditions for registration as recommended by the Republic of Korea's Animal, Plant & Fisheries Quarantine & Inspection Agency. Three farms were selected based on their history of co-infection with PCV2 and M. hyopneumoniae. On each farm, a total of 80 3-week-old pigs were randomly allocated to one of two treatment groups: (i) vaccinated (n=40) and (ii) unvaccinated (n=40) animals at 3 weeks of age. Protection by the bivalent vaccine helped increase the market weight by 6.2 kg/pig (106.2 kg in vaccinated group vs. 100 kg in unvaccinated group; P
- Published
- 2015
19. Increased fucosyl glycoconjugate by Mycoplasma hyopneumoniae enhances adherences of Pasteurella multocida type A in the ciliated epithelial cells of the respiratory tract
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Kyuhyung Choi, Ikjae Kang, Changhoon Park, Chanhee Chae, Jiwoon Jeong, and Su-Jin Park
- Subjects
0301 basic medicine ,Respiratory Mucosa ,Co infection ,Enzootic pneumonia ,Mycoplasma hyopneumoniae ,Pasteurellamultocida ,DNA, Bacterial ,Pasteurella multocida ,040301 veterinary sciences ,Glycoconjugate ,Swine ,Pasteurella Infections ,In situ hybridization ,Bacterial Adhesion ,Microbiology ,0403 veterinary science ,03 medical and health sciences ,Porcine enzootic pneumonia ,medicine ,Animals ,Cilia ,In Situ Hybridization ,Fucose ,chemistry.chemical_classification ,General Veterinary ,biology ,Coinfection ,04 agricultural and veterinary sciences ,General Medicine ,respiratory system ,Pneumonia of Swine, Mycoplasmal ,biology.organism_classification ,veterinary(all) ,Epithelium ,respiratory tract diseases ,Co-infection ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,Plant Lectins ,Glycoconjugates ,Respiratory tract ,Research Article - Abstract
Background: The objective of this study was to elucidate the pathogenic mechanisms of how Mycoplasma hyopneumoniae enhances secondary Pasteurella multocida type A infection which leads to porcine enzootic pneumonia in infected pigs. Sixteen pigs were experimentally infected with M. hyopneumoniae and then euthanized at 7, 14, 21 and 28 days post inoculation. In situ hybridization for M. hyopneumoniae DNA and Ulex europaeus agglutinin-I (UEA-I) lectin histochemistry for fucosyl glycoconjugate, was performed in serial lung sections to determine alteration of fucosyl glycoconjugate in M. hyopneumoniae-infected bronchial and bronchiolar epithelium. Bacterial overlay assay was performed to determine the affinity of P. multocida type A with L-fucose. Results: The luminal surface of bronchial and bronchiolar epithelial cells that were stained with UEA-I always showed hybridization signals for M. hyopneumoniae but it was negative in the unaffected parts of the lung from M. hyopneumoniae-infected pigs and in lung from negative control pigs. Colocalization of M. hyopneumoniae and UEA-I was especially prominent in the luminal surface of bronchial and bronchiolar epithelial cells in serial section of lung. The mean number of M. hyopneumoniae-positive cells correlated with the mean number of UEA-I-positive cells in lungs from infected pigs throughout the experiment. All eight P. multocida type A isolates from naturally occurring enzootic pneumonia, bound strongly at levels of 2 mu g and 5 mu g of L-fucose. Conclusions: The results of the present study demonstrate that M. hyopneumoniae increases the L-fucose composition to enhance adherence of P. multocida type A to the bronchial and bronchiolar epithelial cells.
- Published
- 2015
20. Comparison of three commercial one-dose porcine circovirus type 2 (PCV2) vaccines in a herd with concurrent circulation of PCV2b and mutant PCV2b
- Author
-
Kyuhyung Choi, Changhoon Park, Chanhee Chae, and Jiwoon Jeong
- Subjects
Circovirus ,Swine ,Sus scrofa ,Viremia ,Antibodies, Viral ,Microbiology ,Interferon-gamma ,Antigen ,medicine ,Animals ,Porcine circovirus associated disease ,Circoviridae Infections ,Swine Diseases ,General Veterinary ,biology ,Viral Vaccine ,Vaccination ,Viral Vaccines ,General Medicine ,biology.organism_classification ,medicine.disease ,Virology ,Antibodies, Neutralizing ,Porcine circovirus ,Immunology ,Mutation ,Vaccine failure - Abstract
Porcine circovirus associated disease (PCVAD) occurred in a farm where pigs had been routinely vaccinated with a commercial PCV2a vaccine. A mutant PCV2b (mPCV2b) was isolated from pigs with PCVAD, perhaps implying a perceived vaccine failure. The objective of this study was to determine and compare the efficacy of 3 one-dose PCV2a vaccines of varying antigen type and dose in the same pig farm with concurrent PCV2b and mPCV2b infection based on clinical (average daily weight gain; ADWG), virological (evidence of viremia), immunological (presence of PCV2-specific neutralizing antibody; NA and interferon-γ secreting cells; IFN-γ-SC), and pathological (lymphoid lesion and PCV2 antigen score within lesion) evaluation. Regardless of which commercial PCV2a vaccine was used, vaccinated animals improved ADWG, and reduced the amount of PCV2b and mPCV2b load in the blood compared to unvaccinated animals. The vaccination of piglets at 3 weeks of age effectively induced higher levels of PCV2b- and mPCV2b-specific NA and IFN-γ-SC compared to unvaccinated animals. A reduction in mPCV2b load in the blood coincided with the appearance of both mPCV2b-specific NA and IFN-γ-SC in the vaccinated animals. The microscopic lymphoid lesions and PCV2-antigen scores within the lymph nodes were significantly lower in vaccinated animals. The perceived vaccine failure could not be explained by incomplete protection of the commercial PCV2a vaccine against mPCV2b. The results of the present study demonstrated that currently available commercial PCV2a vaccines are protective against concurrent PCV2b and mPCV2b infection based on clinical, virological, immunological, and pathological evaluations under field conditions.
- Published
- 2014
21. Comparison of experimental infection with northern and southern Vietnamese strains of highly pathogenic porcine reproductive and respiratory syndrome virus
- Author
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Kyuhyung Choi, C. Chae, Changhoon Park, D.Q. Nguyen, T.T. Nguyen, Jiwoon Jeong, T.D. Do, and T.H. Le
- Subjects
Swine ,viruses ,Vietnamese ,Porcine Reproductive and Respiratory Syndrome ,Virulence ,Polymerase Chain Reaction ,Virus ,Pathology and Forensic Medicine ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,In Situ Hybridization ,Swine Diseases ,Lung ,General Veterinary ,biology ,Respiratory disease ,virus diseases ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,medicine.disease ,Virology ,Immunohistochemistry ,language.human_language ,Open reading frame ,medicine.anatomical_structure ,Viral replication ,language - Abstract
The aim of this study was to compare the virulence of northern and southern Vietnamese strains of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) as assessed by the level of viral replication, gross and microscopical lung lesions and virus distribution in experimentally infected pigs. The northern and southern Vietnamese HP-PRRSV strains share 96.7% (non-structural protein 2) and 99.3% (open reading frame 5) nucleotide identity. On experimental challenge, approximately 50% of pigs infected with northern Vietnamese HP-PRRSV died, while death was not observed in any pigs infected with southern Vietnamese HP-PRRSV. Mean viral titres (expressed as log(10)TCID(50)/ml) were significantly (P0.05) higher in sera and lungs from pigs infected with the northern Vietnamese HP-PRRSV than from those infected with the southern Vietnamese strain at multiple time points. Lung lesion scores and PRRSV antigen within pulmonary and lymphoid lesions were significantly (P0.05) higher in pigs infected with northern Vietnamese HP-PRRSV than in those receiving southern Vietnamese HP-PRRSV at multiple time points. PRRSV antigens were observed in cardiac myocytes, gastric and renal tubular epithelial cells and astrocytes and microglia of white matter in the brain from pigs infected with the northern Vietnamese HP-PRRSV strain only. Thus, genetic similarity did not predict the degree of virulence of these strains. Northern Vietnamese HP-PRRSV was more virulent and had extended tissue tropism when compared with southern Vietnamese HP-PRRSV.
- Published
- 2014
22. Comparison of commercial type 1 and type 2 PRRSV vaccines against heterologous dual challenge
- Author
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S.-J. Park, Kyuhyung Choi, Changhoon Park, Ikjae Kang, Chanhee Chae, and Jiwoon Jeong
- Subjects
0301 basic medicine ,Genotype ,Swine ,040301 veterinary sciences ,viruses ,animal diseases ,Porcine Reproductive and Respiratory Syndrome ,Heterologous ,Biology ,0403 veterinary science ,03 medical and health sciences ,Immune system ,Immunity ,Interferon ,medicine ,Animals ,Porcine respiratory and reproductive syndrome virus ,General Veterinary ,Vaccination ,virus diseases ,Viral Vaccines ,04 agricultural and veterinary sciences ,General Medicine ,respiratory system ,Porcine reproductive and respiratory syndrome virus ,biology.organism_classification ,Virology ,030104 developmental biology ,Immunization ,Immunology ,medicine.drug - Abstract
This study was to compare the effect of vaccination of pigs with either type 1 or type 2 porcine reproductive and respiratory syndrome virus (PRRSV) against heterologous dual challenge of both genotypes. Pigs were administered type 1 (UNISTRAIN PRRS) or type 2 (Fostera PRRS) PRRSV vaccine at 28 days of age and inoculated intranasally with both genotypes at 63 days of age. Vaccination of pigs with type 1 PRRSV was able to reduce the levels of type 1 but not type 2 PRRSV viraemia, whereas vaccination of pigs with type 2 PRRSV was able to reduce the levels of type 1 and type 2 PRRSV viraemia against a dual challenge. Vaccination of pigs with type 2 PRRSV significantly reduced lung lesions after dual challenge compared with vaccination of pigs with type 1 PRRSV. Vaccination of pigs with type 2 PRRSV induced higher numbers of type 1 and type 2 PRRSV-specific interferon-γ secreting cells compared with vaccination of pigs with type 1 PRRSV after dual challenge. The results of this study demonstrated that vaccination of pigs with type 2 PRRSV is efficacious in protecting growing pigs from respiratory disease after heterologous dual type 1 and type 2 PRRSV challenge compared with vaccination of pigs with type 1 PRRSV.
- Published
- 2016
23. Development of porcine circovirus 2 (PCV2) open reading frame 2 DNA vaccine with different adjuvants and comparison with commercial PCV2 subunit vaccine in an experimental challenge.
- Author
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Changhoon Park, Jiwoon Jeong, Kyuhyung Choi, Su-Jin Park, Ikjae Kang, and Chanhee Chae
- Abstract
Copyright of Canadian Journal of Veterinary Research / Revue Canadienne de Recherche Vétérinaire is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
24. Improved growth performance by type 2 porcine reproductive and respiratory syndrome virus (PRRSV)-based modified live vaccine in a herd with concurrent circulation of type 1 and type 2 PRRSV.
- Author
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Ikjae Kang, Hei Suk Kang, Jiwoon Jeong, Changhoon Park, Seeun Kim, Kyuhyung Choi, Su-Jin Park, Sung-Min Hwang, Beomseok Oh, Sung-Hoon Kim, Byunghak Kang, and Chanhee Chae
- Subjects
PORCINE reproductive & respiratory syndrome ,VIRUS diseases in swine ,SWINE vaccination ,LUNG diseases ,MIXED infections - Abstract
The objective of this study was to evaluate type 2 porcine reproductive and respiratory syndrome virus (PRRSV)-based modified live vaccine in a herd with concurrent circulation of type 1 and type 2 PRRSV. Type 2 PRRSV- based modified live vaccine improved average daily gain by 48.24 grams/pig/day (631.17 grams/pig/day in the vaccinated group vs 582.93 grams/pig/day in the unvaccinated group; P < 0.05). Pathological examination indicated that the vaccination effectively reduced microscopic lung lesions compared with the control animals. The protection of this vaccine against type 1 and type 2 PRRSV provides clinical control of co-infection with both genotypes under field conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2017
25. Evaluation of the new commercial recombinant chimeric subunit vaccine PRRSFREE in challenge with heterologous types 1 and 2 porcine reproductive and respiratory syndrome virus.
- Author
-
Jiwoon Jeong, Changhoon Park, Kyuhyung Choi, and Chanhee Chae
- Abstract
Copyright of Canadian Journal of Veterinary Research / Revue Canadienne de Recherche Vétérinaire is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
26. Increased fucosyl glycoconjugate by Mycoplasma hyopneumoniae enhances adherences of Pasteurella multocida type A in the ciliated epithelial cells of the respiratory tract.
- Author
-
Changhoon Park, Jiwoon Jeong, Ikjae Kang, Kyuhyung Choi, Su-Jin Park, and Chanhee Chae
- Subjects
MYCOPLASMA hyopneumoniae ,PASTEURELLA multocida ,BACTERIAL adhesion ,EPITHELIAL cells ,RESPIRATORY infections ,PNEUMONIA ,SWINE - Abstract
Background: The objective of this study was to elucidate the pathogenic mechanisms of how Mycoplasma hyopneumoniae enhances secondary Pasteurella multocida type A infection which leads to porcine enzootic pneumonia in infected pigs. Sixteen pigs were experimentally infected with M. hyopneumoniae and then euthanized at 7, 14, 21 and 28 days post inoculation. In situ hybridization for M. hyopneumoniae DNA and Ulex europaeus agglutinin-I (UEA-I) lectin histochemistry for fucosyl glycoconjugate, was performed in serial lung sections to determine alteration of fucosyl glycoconjugate in M. hyopneumoniae-infected bronchial and bronchiolar epithelium. Bacterial overlay assay was performed to determine the affinity of P. multocida type A with L-fucose. Results: The luminal surface of bronchial and bronchiolar epithelial cells that were stained with UEA-I always showed hybridization signals for M. hyopneumoniae but it was negative in the unaffected parts of the lung from M. hyopneumoniae-infected pigs and in lung from negative control pigs. Colocalization of M. hyopneumoniae and UEA-I was especially prominent in the luminal surface of bronchial and bronchiolar epithelial cells in serial section of lung. The mean number of M. hyopneumoniae-positive cells correlated with the mean number of UEA-I-positive cells in lungs from infected pigs throughout the experiment. All eight P. multocida type A isolates from naturally occurring enzootic pneumonia, bound strongly at levels of 2 μg and 5 μg of L-fucose. Conclusions: The results of the present study demonstrate that M. hyopneumoniae increases the L-fucose composition to enhance adherence of P. multocida type A to the bronchial and bronchiolar epithelial cells. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
27. In vivo Activity of Lactobacillus plantarum on Reduction in Enterotoxigenic Escherichia coli and Shiga Toxin-Producing E. coli in Postweaning Pigs.
- Author
-
Changhoon Park, Jiwoon Jeong, Kyuhyung Choi, Duck-Il Shin, Jeong, A. Rong, Sung-Hoon Kim, and Chanhee Chae
- Subjects
LACTOBACILLUS plantarum ,SWINE diseases ,EDEMA ,ESCHERICHIA coli diseases ,BACTERIAL toxins ,ANTIBIOTICS - Abstract
The objective of this study was to determine the effect of Lactobacillus plantarum on enterotoxigenic Escherichia coli (ETEC) and Shiga toxin-producing E. coli (STEC) in order to reduce lesions and fecal shedding for the control of colibacillosis and edema disease in postweaning pigs. ETEC K88 colonized in greater abundance on the surface of the small intestinal tract of non-L. plantarum-fed pigs compared to L. plantarum-fed pigs. Reduced intestinal adherence and fecal shedding of ETEC K88 was observed in the L. plantarum-fed pigs, whereas brain lesions and fecal shedding of STEC F18 remained unchanged. The results of this study demonstrated that L. plantarum appeared to have beneficial effects on the colibacillosis but not edema disease in postweaning pigs. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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