• The Korean Journal of Physiology and Pharmacology
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• v.18 no.6
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• pp.497-502
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• 2014

Extracellular nicotinamide adenine dinucleotide (NAD) cleaving activity of a particular cell type determines the rate of the degradation of extracellular NAD with formation of metabolites in the vicinity of the plasma membrane, which has important physiological consequences. It is yet to be elucidated whether intact human neutrophils have any extracellular NAD cleaving activity. In this study, with a simple fluorometric assay utilizing $1,N^6$-ethenoadenine dinucleotide (etheno-NAD) as the substrate, we have shown that intact peripheral human neutrophils have scant extracellular etheno-NAD cleaving activity, which is much less than that of mouse bone marrow neutrophils, mouse peripheral neutrophils, human monocytes and lymphocytes. With high performance liquid chromatography (HPLC), we have identified that ADP-ribose (ADPR) is the major extracellular metabolite of NAD degradation by intact human neutrophils. The scant extracellular etheno-NAD cleaving activity is decreased further by N-formyl-methionine-leucine-phenylalanine (fMLP), a chemoattractant for neutrophils. The fMLP-mediated decrease in the extracellular etheno-NAD cleaving activity is reversed by WRW4, a potent FPRL1 antagonist. These findings show that a much less extracellular etheno-NAD cleaving activity of intact human neutrophils compared to other immune cell types is down-regulated by fMLP via a low affinity fMLP receptor FPRL1.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.83-86
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• 2003

Major advances in positive-sense RNA virus research have been facilitated by the development of reverse genetics systems. These systems consist of an infectious cDNA clone that encompasses the genome of the virus in question. This clone is then used as a template for the subsequent synthesis of infectious RNA for the generation of synthetic viruses. However, the construction of infectious cDNA for the Japanese encephalitis virus (JEV) has been repeatedly thwarted by the instability of its cDNA. As JEV is an important human pathogen that causes permanent neuropsychiatric sequelae and even fatal disease, a reliable reverse genetics system for this virus is highly desirable. The availability of this tool would greatly and the development of effective vaccines as well as facilitate studies into the basic biology of the virus, including the molecular mechanisms of viral replication, neurovirulence, and pathogenesis. We have successfully constructed a genetically stable infectious JEV cDNA containing full-length viral RNA genome. Synthetic RNA transcripts generated in vitro from the cDNA were highly infectious upon transfection into susceptible cells, and the cDNA remained stable after it had been propagated in E. coli for 180 generations. Using this infectious JEV cDNA, we have successfully expressed a variety of reporter genes from the full-length genomic and various subgenomic RNAs in vitro transcribed from functional JEV cDNAS. In summary, we have developed a reverse genetics system for JEV that will greatly facilitate the research on this virus in a variety of different fields. It will also be useful as a heterologous gene expression vector and aid the development of a vaccine against JEV.

• Journal of Korean Critical Care Nursing
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• v.8 no.2
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• pp.66-79
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• 2015

Purpose: This study aimed to derive the elements for effectively improving the management of emerging infectious diseases in the emergency room in large general hospitals. Methods: This research involved an analytic hierarchy process analysis of 10 experienced nurses working in a large general hospital located in the Seoul metropolitan area. The weighted values of the criteria for evaluating the importance of the management elements of patients with emerging infectious diseases in the emergency room of large general hospitals were derived using an analytic hierarchy process survey. Results: The results of the analytic hierarchy process analysis showed that experts considers responsiveness (0.291) as most important with respect to the criteria for the policy for isolation and control of infectious patients. The order of importance of the criteria for the policy for isolation and control of infectious patients were as follows: responsiveness (0.291), economical efficiency (0.257), feasibility (0.242), and sustainability (0.209). Subsequently, the weighted values of the management of the policy elements were determined based on the derived importance of the criteria mentioned above. These were, in order of priority, the construction of communication channels with the government authorities when dealing with emerging infectious diseases (15.9%), the equipment and provision of personal protective equipment to protect nurses from infection and dissemination of material (14.6%), and the operation of the isolation room and patient separation systems (14.1%). Conclusion: This study suggests critical strategies for infection control during a pandemic of emerging infectious disease.

• Parasites, Hosts and Diseases
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• v.55 no.3
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• pp.313-317
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• 2017

Paragonimiasis is a parasitic disease caused by Paragnonimus species. The primary site of infection is the lung, and extrapulmonary involvement is also reported. When infected with Paragonimus westermani, which is the dominant species in Korea, the central nervous system is frequently involved along with the liver, intestine, peritoneal cavity, retroperitoneum, and abdominal wall. Ectopic paragonimiasis raises diagnostic challenge since it is uncommon and may be confused with malignancy or other inflammatory diseases. Here, we report an ectopic paragonimiasis case initially presented with recurrent abdominal pain. The patient developed abdominal pain 3 times for the previous 3 years and the computed tomography (CT) of the abdomen revealed fluid collection with wall enhancement. Recurrent diverticulitis was initially suspected and part of the ascending colon was resected. However, the specimen showed intact colon wall without evidence of diverticulitis and multiple parasite eggs and granulomas were found instead. The size of about $70{\mu}m$, the presence of an operculum and relatively thick egg shell suggested eggs of Paragonimus species. With appropriate exposure history and a positive antibody test, the definitive diagnosis was made as peritoneal paragonimiasis.

• Korean Journal of Veterinary Research
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• v.53 no.1
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• pp.25-28
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• 2013

The aim of this study was to applicate and evaluate a SYBR Green real-time PCR for the specific detection of Salmonella spp. Specificity of the PCR method was confirmed with 48 Salmonella spp. and 5 non-Salmonella strains using invA gene primer. The average threshold cycle ($C_T$) of Salmonella spp. was $11.83{\pm}0.78$ while non-Salmonella spp. was $30.86{\pm}1.19$. Correlation coefficients of standard curves constructed using $C_T$ versus copy number of Salmonella Enteritidis ATCC 13076 showed good linearity ($R^2=0.993$; slope = 3.563). Minimum level of detection with the method was > $10^2$ colony forming units (CFU)/mL. These results suggested that the SYBR Green real-time PCR might be applicable for the specific detection of Salmonella spp. isolates.

• Journal of Microbiology
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• v.44 no.3
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• pp.327-335
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• 2006

An epidemiological survey of human enterobacterial infections was conducted to determine the prevalence of enteropathogens in the Republic of Korea during one year, 2003. We tested for infectious diseases in 26,992 stool samples obtained from people who visited clinics located in six big cities and six rural provinces. From these samples, we isolated 1,291 cases of enteritis bacterial infection (4.8%). In the urban areas, 821 cases of bacterial infection (6.4%) were identified and, in the rural areas, 479 bacterial strains (3.3%) were isolated. Seasonal patterns were seen for diarrhea associated with S. aureus, S. coli and V. parahaemolyticus, while Salmonella and Shigella infections showed slight seasonal variation. We found that S. aureus and Salmonella were more frequently isolated from children and the elderly; however, the prevalence of E. coli, V. parahaemolyticus, and Shigella were similar in different age groups. Routine monitoring of these infections is considered a worthwhile means by which to elucidate their epidemiology and modes of transmission and ultimately to control them more effectively. Continuous laboratory-based surveillance for findings of enteritis bacterial infection should be emphasized in the prevention of these infections.

• BMB Reports
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• v.51 no.1
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• pp.33-38
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• 2018

Sterol regulatory element-binding protein-1c (SREBP1c) plays an important role in triglyceride (TG) homeostasis. Although our previous study showed that hepatitis C virus core-binding protein 6 (HCBP6) regulates SREBP1c expression to maintain intracellular TG homeostasis, the mechanism underlying this regulation is unclear. In the present study, we found that HCBP6 increased intracellular TG levels by upregulating SREBP1c expression. HCBP6 increased SREBP1c transcription by directly binding to the SREBP1c promoter (at the -139- to +359-bp region). Moreover, we observed that HCBP6 interacted with $C/EBP{\beta}-binding$ site in the SREBP1c promoter both in vitro and in vivo. These results indicate that HCBP6 upregulates human SREBP1c expression by binding to the $C/EBP{\beta}-binding$ site in the SREBP1c promoter.

• Molecules and Cells
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• v.22 no.3
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• pp.336-342
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• 2006

Real time reverse transcription (RT)-PCR was used to quantify the expression of the botulinum neurotoxin type A (BoNT/A) gene (cntA) by normalization with the expression of 16S rRNA. The method were confirmed by monitoring the mRNA levels of cntA during growth in five type A strains. In all but one of the strains the expression of cntA mRNA was maximal in the late exponential phase, and approximately 35-fold greater than in the early exponential phase. The concentration of the extracellular BoNT/A complex detected by ELISA was highest in stationary phase. Sodium nitrite and sorbic acid completely inhibited growth at 20 ppm and $4mg\;ml^{-1}$, respectively. CntA expression became lower in proportion to the concentration of sorbic acid, and this reduction was confirmed by mouse bioassay. Our results show that real time RT-PCR can be used to quantify levels of C. botulinum type A neurotoxin transcripts and to assess the effects of food additives on botulinal risk.

• Journal of the Korean Society of School Health
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• v.34 no.1
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• pp.76-86
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• 2021

Purpose: This study was conducted to describe the experience of school health teachers in regard to the COVID-19 pandemic in South Korea. Methods: We conducted a qualitative study using content analysis. Ten school health teachers were recruited from 6 elementary schools, 2 middle schools and 2 high schools in Seoul, using purposive sampling. They participated in semi-structured in-depth interviews in person or using an online communication system from January to February, 2021. Interviews were transcribed verbatim and analysed using qualitative content analysis. Results: Three main categories and nine generic categories emerged from the analysis. Firstly, it was discovered that school health teachers had psychological and physical stress to cope with COVID-19 due to the 1) fear of the unexpected infectious disease, 2) burden of having to deal with it alone, 3) breakdown of personal life and physical exhaustion and 4) heavy duty as a health teacher caused by the lack of an organic cooperation system with institutions related to school infectious diseases. Secondly, school health teachers had an increased sense of empowerment in regard to infectious disease management as a result of 1) feeling rewarded and appreciated and 2) gaining confidence and trust in infectious disease management. Finally, school health teachers experienced the urgent need for an effective response strategy for infection control because of the 1) confusion over infectious disease response due to lack of practical manuals applicable to the field as well as training, 2) disappointing response system without an expert response team dedicated to managing infectious diseases in schools, and 3) growing awareness of the need for change. Conclusion: It is expected that school health teachers' experience of COVID-19 will be used as important data for building effective and advanced school infectious disease response systems.

• Journal of Korean Dental Hygiene Science
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• v.3 no.2
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• pp.27-37
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• 2020

This study investigated the relationship between knowledge of COVID-19, the risk of exposure to subjective infectious diseases, and the degree of infection control practices for dental personnel. For dental personnel currently working in dentistry, a survey consisting of 10 questions about COVID-19 knowledge and 63 questions about infection control practices was conducted. This study analyzed 126 survey data collected by distributing questionnaires form May 30 to June 20, 2020. Data was analyzed using t-test, ANOVA, and Pearson correlation. The average level of knowledge of COVID-19 was 5.44 out of 10, the average risk of exposure to infectious diseases was 3.86 out of 5, and the average level of infection control practices was 4.05 out of 5. The risk of exposure to infectious diseases was positively correlated with dental waste (r=.184). It was found that there was a significant positive correlation between infection control practices and sub-factors of infection control practices (p<0.001). To prevent the spread of COVID-19 and infectious diseases and to reduce the risk of exposure to infectious diseases for dental personnel, the practice of infection control should be improved. It is necessary to cultivate infection control experts and have mandatory infection control education and social regulations.