• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.241-246
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• 2015

To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS-binding lytic bacteriophage. A non-virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2-N6, was established through in vivo pathogenicity and protection efficacy tests. SR2-N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2-N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.

• Advances in environmental research
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• v.11 no.1
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• pp.17-30
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• 2022

Road transport allows all forms of land conditions to be met at less cost. Because of this function, despite numerous disadvantages, it becomes the most frequently used method of transport, especially in underdeveloped or developing countries. One of the most significant factors used in evaluating the atmosphere's air quality is the amount of CO₂, increasing people's density in indoor spaces. The amount of CO₂ indoors is, therefore, vital to determine. In this study, CO₂ and temperature measurements made on nine different bus journey was made in Turkey. The minimum and maximum values were recorded as 555 ppm and 3000 ppm CO₂, respectively, in the measurements. On all journeys, the average concentration is 1088.72 ppm. The minimum and maximum values were measured as 17.4℃ and 32.7℃ in the temperature measurements, and the average of all trips was calculated to be 25.76℃. In this study conducted before the Covid-19 pandemic, it was determined that the amount of CO₂ increased with the density and insufficient ventilation in the buses. The risk of infection increases in places with high human density and low clean air. For situations such as pandemics, CO₂ measurement is a rapid indicator of determining human density.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.799-802
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• 2012

Background: Human papillomavirus (HPV) is a very common sexually transmitted disease affecting both men and women and is responsible for different ano-genital cancers in either sex. Co-existing sexually transmitted infections (STI) including HIV have been considered as important co-factors for carcinogenesis induced by HPV. The purpose of this study was to determine the prevalence of any HPV, HPV 16 and HPV 18 and also concomitant STIs among female sex workers (FSW), men having sex with men (MSM) and injectable drug users (IDU). Material and Method: This cross-sectional study was conducted among 45 FSWs, 26 MSMs and 58 IDUs who attended the STI or de-addiction clinics. Genital scrape samples collected from glans penis and coronal sulcus in males and cervical squamo-columnar junction in females were tested for HPV DNA by PCR using HPV L1 consensus primer. Type specific PCR to detect HPV 16 and 18 was done on the samples positive on consensus PCR. All participants were tested for associated STIs including HIV and hepatitis B and cervical cytology was done on all females. Results: Among the FSWs, HPV was detected in 73.3% and HPV 16 and 18 was detected in 25.7%. Though the HPV prevalence was similarly high among MSMs (69.2%) and IDUs (72.4%), the prevalence of HPV 16 and 18 was much lower in these groups compared to the FSWs. Prevalence of cervico-vaginal infection with Trichomonas vaginalis and syphilis was significantly higher in the HPV positive women compared to the HPV negative women. There was no statistically significant difference in the prevalence of other STIs among HPV positive and negative women and men. Conclusion: HPV infection is highly prevalent among FSW, MSM and IDUs. Trichomonas vaginalis infection is more frequent in HPV positive women.

• Molecules and Cells
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• v.45 no.12
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• pp.896-910
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• 2022

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and potentially fatal virus. So far, most comprehensive analyses encompassing clinical and transcriptional manifestation have concentrated on the lungs. Here, we confirmed evident signs of viral infection in the lungs and spleen of SARS-CoV-2-infected K18-hACE2 mice, which replicate the phenotype and infection symptoms in hospitalized humans. Seven days post viral detection in organs, infected mice showed decreased vital signs, leading to death. Bronchopneumonia due to infiltration of leukocytes in the lungs and reduction in the spleen lymphocyte region were observed. Transcriptome profiling implicated the meticulous regulation of distress and recovery from cytokine-mediated immunity by distinct immune cell types in a time-dependent manner. In lungs, the chemokine-driven response to viral invasion was highly elevated at 2 days post infection (dpi). In late infection, diseased lungs, post the innate immune process, showed recovery signs. The spleen established an even more immediate line of defense than the lungs, and the cytokine expression profile dropped at 7 dpi. At 5 dpi, spleen samples diverged into two distinct groups with different transcriptome profile and pathophysiology. Inhibition of consecutive host cell viral entry and massive immunoglobulin production and proteolysis inhibition seemed that one group endeavored to survive, while the other group struggled with developmental regeneration against consistent viral intrusion through the replication cycle. Our results may contribute to improved understanding of the longitudinal response to viral infection and development of potential therapeutics for hospitalized patients affected by SARS-CoV-2.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.445-449
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• 2014

The incidence of Cherry necrotic rusty mottle virus (CNRMV) and Cherry green ring mottle virus (CGRMV) have recently been occurred in Korea, posing a problem for sweet cherry cultivation. Since infected trees have symptomless leaves or ring-like spots on the pericarp, it is difficult to identify a viral infection. In this study, the incidence of CNRMV and CGRMV in sweet cherry in Gyeongbuk province was surveyed using a newly developed duplex reverse transcriptase polymerase chain reaction (RT-PCR) method that can detect both viruses in a single reaction. CNRMV and CGRMV co-infection rates were 29.6%, 53.6%, and 17.6%, respectively, in samples collected from three different sites (Daegu, Gyeongju and Gyeongsan) in Gyeongbuk province during 2012 and 2013. This duplex RT-PCR method offers a simple, rapid, and effective way of identifying CNRMV and CGRMV simultaneously in sweet cherry trees, which can aid in the management of viral infections that could undermine yield.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.505-510
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• 2001

A total of 701 swine sera from 55 swine farms (Mar, 1998 through Feb, 2001) were nation-widely collected for the presence of antibody to porcine parvovirus (PPV) in sows and 30-, 60-, 90-day-old pigs. Sero-prevalence by haemagglutination inhibition assay with guinea pig red blood cells was investigated on the basis of year, region and season, respectively. In general, there was no significant difference with gradual decrease of passive immunity for the sero-prevalence to PPV in sows and 30-, 60-, 90-day-old pigs for the period of 1999 and 2000. However, regional variation was observed in the provinces of Kyonggi, Choongnam and Kyungnam, Natural infection of the virus in 90-day-old pigs was increased during the fall and the winter. Thus, it seems that the natural infection of PPV in growing pigs may be attributed to the increased outbreak of postweaning multisystemic wasting syndorme in co-infection with porcine circoviruses.

• The Plant Pathology Journal
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• v.24 no.4
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• pp.439-446
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• 2008

A fungicidal spray program for effective control of three major apple diseases in Korea (white rot, bitter rot, and Marssonina blotch) was developed. This was based on our previous studies showing that application of ergosterol biosynthesis inhibitors (EBIs) in early or mid-August can eradicate white rot infection in fruit and that some protective fungicides show after-infection activity against white rot. The basic spray program focused on control of white rot, the main target disease, and the fungicides were sprayed at 15-day intervals from petal fall to late August using fungicides that show after-infection and EBI activity. The basic spray program was modified over 4 successive years to improve control efficacy against bitter rot and Marssonina blotch, which sometimes cause as much damage as white rot. Modifications to the regime were made every year by replacing one fungicide in the basic program at a specific spraying time. Substitution of only one fungicide in the spray program, even early in the growing season, greatly influenced the final disease incidence at harvest. Applying this principle, a moderately efficient spray program for cv. Fuji that increased the spray interval from 10 to 15 days and thus reduced the number of sprays required per crop season was developed.

• IMMUNE NETWORK
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• v.10 no.4
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• pp.126-134
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• 2010

Background: $CD8^+$ T cells contribute to the clearance of Hepatitis B virus (HBV) infection and an insufficient $CD8^+$ T cell response may be one of the major factors leading to chronic HBV infection. Since the HBx antigen of HBV can up-regulate cellular expression of several immunomodulatory molecules, we hypothesized that HBx expression in hepatocytes might affect $CD8^+$ T cell activity. Methods: We analyzed the activation and apoptosis of $CD8^+$ T cells co-cultured with primary hepatocytes rendered capable of expressing HBx by recombinant baculovirus infection. Results: Expression of HBx in hepatocytes induced low production of $interferon-{\gamma}$ and apoptosis of CD8+ T cells, with no effect on CD8 T cell proliferation. However, transcriptional levels of H-2K, ICAM-1 and PD-1 ligand did not correlate with HBx expression in hepatocytes. Conclusion: Our results suggest that HBx may inhibit $CD8^+$ T cell response by regulation of $interferon-{\gamma}$ production and apoptosis.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.425-428
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• 2007

From January to June 2006, 54 suckling pigs had been submitted in virology lab., College of Veterinary Medicine, Seoul National University. All pigs had suffered from various symptoms such as respiratory sign, enteric signs, neurologic signs, etc. Among 54 pigs, 24 pigs (44.4%) were positive for porcine hemagglutinating encephalomyelitis virus (HEV) through reverse transcription-nested polymerase chain reaction. According to this result, HEV infections seemed to be prevalent and widespread in Korean swine farms, and the infection is associated with respiratory signs and neurologic signs more than enteric signs. The HEV positive pigs showing respiratory signs were co-infected with viruses such as PRRSV, and PCV2, or bacteria such as Pasteurella spp. The single infection may subclinically have an influence on outbreak of other respiratory pathogens in suckling pigs.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.235-243
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• 2017

Salmonella (S.) Typhimurium is highly contagious, and its infection may rapidly spread within pig populations of herd. According to the survey (1,191 pigs) from 2003 to 2012, 155 pigs (13.0%) were diagnosed as salmonellosis in Jeju. Major porcine salmonellosis cases (88.4%) were concentrated in 4- to 12-week-old weaned pigs, but 6 pigs (3.9%) under 4 weeks old were also diagnosed. Based on the histopathologic examinations, ulcerative enteritis (63.9%) in the large intestine and/or paratyphoid nodules formation (57.4%) in the liver were most prevalent lesions in porcine salmonellosis. Single infection of S. Typhimurium and mixed infection with more than 2 pathogens were detected in 38 (24.5%) and 117 (75.5%) in pigs, respectively. Co-infections of Porcine reproductive and respiratory syndrome virus and Porcine circovirus type 2 were very common in porcine salmonellosis in Jeju and detected in 84 (54.2%) and 59 (38.1%) pigs, respectively. Based on the serotyping tests using 41 bacterial isolates, S. Typhimurium and S. Rissen were confirmed in 39 (95.1%) and 2 (4.9%) cases, respectively.