• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.101-104
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• 2019

This study examined the disinfection conditions (exposure time, 0-30 min; exposure temperature, $4^{\circ}C-65^{\circ}C$) of hypochlorous acid water (HOCl) in automobile disinfection equipment. The study tested poliovirus type 1 (PV1), low pathogenic avian influenza virus (AIV, H9N2), and foot and mouth disease virus (FMDV, O type). As a result, the PV1 and FMD viruses were inactivated easily (virus titer 4 log value) by HOCl (> 100 ppm) but the AIV required higher exposure temperatures (> $55^{\circ}C$). In conclusion, the exposure temperature and time are important factors in deactivating AIV and FMDV.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.178-185
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• 2008

Avian influenza virus (AIV) is recognized as key to the emergence of pandemic influenza for humans; there are growing concerns that AIV H9N2 may become more efficient to transmit to humans in the near future, since the infection of poultry with AIV H9N2 has been common in recent years. In this study, we aimed to produce antisera recognizing the HA and NA proteins of AIV H9N2. Initially, coding sequences corresponding to the N-terminal regions of the HA and NA proteins of the Korean AIV H9N2 (A/Ck/Kr/MS96/96) isolated from a domestic chicken were amplified from the genomic RNA. Following cloning of the amplified cDNA fragments into pGEX4T-1 vector, two GST-fusion proteins (GST-HAln and GST-NAn) were expressed in E. coli BL21 and purified with glutathione sepharose columns; the recombinant GST-HAln and GST-NAn proteins were both used as immunogens in rabbits. The antigenicity of the rabbit antisera was analyzed by immunoblotting of the cell lysates prepared from AIV H9N2-infected MDCK cells. Overall, the recombinant HAln and NAn proteins fused to the C-terminus of GST and the rabbit antisera raised against the corresponding recombinant proteins would provide a valuable reagent for AIV diagnosis and basic research.

• Korean Journal of Poultry Science
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• v.31 no.2
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• pp.119-128
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• 2004

Highly Pathogenic Avian Influenza (HPAI) is a very acute systemic disease in poultry, particularly in chickens and turkeys caused by HPAI viruses. An outbreak of HPAI caused by subtype H5N1, was first reported in a broiler breeder farm on December 10, 2003 in Korea, although there had been twenty one outbreaks of the disease reported in the world before. Since mid-December 2003, eight Asian countries have confirmed outbreaks of HPAI due to the same subtype. The outbreak has also resulted in at least twenty three fatal human cases in Vietnam and Thailand as of May 17, 2004 according to the WHO. Regarding the first outbreak of recent Asian HPAI, it has been suspected that some Asian countries with the exception of Korea and Japan veiled the fact of HPAI outbreaks since the last half of 2003, even though it was first reported in Korea. There have been total nineteen outbreaks of HPAI among chicken and duck farms in 10 provinces in Korea since Dec. 2003 and approximately 5,280,000 birds were slaughtered from 392 farms for eradication of the disease and preemptive culling. The origin of the H5Nl HPAI virus introduced into the country are unknown and still under epidemiological investigation. Current status of outbreaks and characteristics of HPAI will be reviewed and discussed on the basis of genetic, virological, clinicopathological, and ecological aspect, as well as future measures for surveillance and prevention of the disease in Korea.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.444-450
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• 2022

The effect of coated polyester (PET) textiles with metal oxide, chitosan, and copper ion on the antibacterial and antiviral activities was evaluated to investigate the applicability of multi-coated PET textiles as antiviral materials. Compared to coated PETs with a single agent, multi-coated PETs reduced the loading amount of coating materials as well as the contact time with bacteria for a bacterial cell number of < 10 CFU/mL, which was not detectable with the naked eyes. Metal oxides generate reactive oxygen species (ROS) such as free radicals by a catalytic reaction, and copper ions can promote contact killing by the generation of ROS. Chitosan not only enhanced antibacterial activities due to amine groups, but enabled it to be a template to load copper ions. We observed that multi-coated PET textiles have both antibacterial activities for E. coli and S. aureus and antiviral efficiency of more than 99.9% for influenza A (H1N1) and SARS-CoV-2. The multi-coated PET textiles could also be prepared via a roll-to-roll coating process, which showed high antiviral efficacy, demonstrating its potential use in air filtration and antiviral products such as masks and personal protective equipment.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.192-198
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• 2023

In this study, the components of microwave-assisted extracts obtained from Thuja orientalis leaves were analyzed, and the cytotoxicity, antibacterial and antiviral activities were evaluated. The predominant components from microwave-assisted extraction were catechin, leucopelargonidin, arecatannin, quinolone, and kaempferol derivatives, which are classified in the flavonoid and tannin groups. We observed that the 0.11 mg/mL of extract concentration did not show cytotoxicity in HaCaT cells. The antibacterial activities were tested according to the guidelines of methods for determining the bactericidal activity of antimicrobial agents. The extracts showed 99.9% antibacterial efficiency against gram-positive S. aureus, while the antibacterial effect on gram-negative E. coli was insignificant. When the extract concentration and contact time with bacteria were increased, 99.9% antibacterial efficiency was observed for E. coli as well as S. aureus. Following the standard to assess the activity of microbicides against viruses in suspension (ASTM-E1052-20), the antiviral efficiency was more than 99.99% for influenza A (H1N1) and SARS-CoV-2. These results suggest its potential use in antiviral disinfectants, surface coatings, personal protective equipment, and textiles.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.41-41
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• 2016

Influenza viruses are RNA viruses that belong to the Orthomyxoviridae family, and those can be divided into three types; A, B, and C, which based on the differences of the inner nucleoproteins and genomic structures. All three genera differ in their genomic structure and nucleoprotein content, they are further classified into various serotypes based on the two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). These glycoproteins play crucial roles in viral infection and replication. Hemagglutinin mediates binding of virions to sialic acid receptors on the surfaces of target cells at the initial stage of infection. Neuraminidase cleaves the glycosidic bonds of sialic acids from the viral and cell surfaces to release the mature virions from infected cells, after viral replication. Because NA plays an important role in the viral life cycle, it is considered an attractive therapeutic target for the treatment of influenza. The methanolic extracts of Phellinus baumii and Phellinus igniarius exhibited significant activity in the neuraminidase inhibition assay. Polyphenolic compounds were isolated from the methanolic extracts. The structures of these compounds were determined to be hispidin, hypholomine B, inoscavin A, davallialactone, phelligridin D, phelligridin E, and phelligridin G by spectroscopic methods. Compounds inhibited the H1N1 neuraminidase activity in a dose-dependent manner with $IC_{50}$ values of 50.9, 22.9, 20.0, 14.2, 8.8, 8.1 and $8.0{\mu}M$, respectively. Moreover, these compounds showed anti-influenza activity in the viral cytopathic effect (CPE) reduction assay using MDCK cells. These results suggests that the polyphenols from P. baumii and P. igniarius are promising candidates for prevention and therapeutic strategies against viral infection.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1348-1353
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• 2005

Purpose : Influenza is a respiratory disease which prevails widely every year and shows high morbidity and mortality among not only chronic invalids and the old, but also among infants and young children. To prevent community-acquired influenza infection, to facilitate prompt antiviral therapy and to avoid unnecessary use of antibiotics, an easy, rapid diagnostic method for the influenza virus is needed. We evaluated a lateral-flow immunoassay(QuickVue Influenza Test), compared to viral culture. Methods : During two consecutive years from Jan. 2004 to June 2004 and from Feb. 2005 to Jan. 2005, 408 patients who were suffering from fever, cough and/or sore throat and myalgia were enrolled in our study. A total of 408 patients were tested with $QuickVue^{(R)}$(Quidel Co., San Diego, USA) influenza rapid antigen test and virus cultures at the same time. Results : Of the 408 patients tested, children who showed positive results at the virus culture numbered 77; among them, 55(71.4 percent) were type A/H3N2 and 22(28.5 percent) were type B. QuickVue influenza test had a sensitivity of 71.4 percent and a specificity of 95.8 percent. The positive and negative predictive values were 79.7 percent and 93.5 percent, respectively. Conclusion : In our study, this test had comparable high sensitivity and high specificity and many advantages, such as being easy to perform and simple to interpret, and showing rapid results. If rapid influenza antigen tests are widely applied in the clinic, we can begin treatment more rapidly and reduce influenza complications and the abuse of antibiotics.

• Pediatric Infection and Vaccine
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• v.24 no.3
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• pp.160-167
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• 2017

Purpose: Because children with asplenia have an increased risk of fulminant infection associated with a high fatality, chemoprophylaxis, and vaccinations against encapsulated bacteria are recommended. However, there have been few reports of the burden of severe bacterial infection and the current status of chemoprophylaxis and immunization among children with asplenia in Korea. Methods: We conducted a retrospective study including children with asplenia who were treated at our institute between January 1997 and December 2016. Results: From a total of 213 children with asplenia, 114 (53.5%) had congenital asplenia and 58 (27.2%) had functional asplenia. The remaining 41 (19.3%) had acquired asplenia with the median age at splenectomy being 12.2 years (range, 5.0 to 16.9 years); the most common cause of splenectomy was hereditary spherocytosis (39.0%). The chemoprophylaxis rate was 16.4%. The immunization rates were 44.1% for pneumococcus, 53.0% for Haemophilus influenzae type B, and 10.7% for meningococcus. The incidence of invasive bacterial infection among children with asplenia was 0.28/100 person-year; a total of six episodes (2.8%) were observed in five patients with congenital asplenia and one patient with functional asplenia. The median age for these infections was 15 months (range, 4 to 68 months). Five of the six episodes were bacteremia, and the other was meningitis. The most common pathogen was Streptococcus pneumoniae (n=3), followed by H. influenzae (n=1). Three of the six patients (50.0%) died, all of whom had pneumococcal bacteremia. None of the six had chemoprophylaxis or proper vaccinations. Conclusions: Although there is an increased risk of a severe infection proper vaccinations and chemoprophylaxis are still lacking. Physicians should be encouraged to implement appropriate chemoprophylaxis and immunizations for patients with asplenia.

• Journal of Korean Medical classics
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• v.22 no.4
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• pp.221-239
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• 2009

Background: The recent outbreak of the novel strain of influenza A (H1N1) virus has raised a global concern of the future risk of pandemic. Traditional Korean Medicine(TKM) has been combatting against contagious diseases and developed its own particular and efficient way in treating those diseases. Objectives: Provide a distinctive and effective TKM method in understanding the principles of treatment, prevention, and contraindications against influenza A through case histories. Method: We revised case histories of eminent doctors of Ming and Qing dynasties according to their clinical manifestations similar to those of influenza A. We also verified prescriptions of the "Dong-uibogam(東醫寶鑑)" through examining clinical practices of China today. Results: 1. The subtypes of Warm disease; Wind Warmth and Pestilence has the most similar clinical manifestation in comparison to Influenza A. Specifying these terms is important in recognizing and classifying various diseases under the name of Warm disease. 2. TKM considered not only external factors but also individual factors like general condition, diet, emotion, constitutional types, etc in the treatment of febrile diseases. 3. TKM developed a new way in the treatment of contagious diseases. considering the characteristics of each pathogen. TKM described the Warm pathogen being light as a feather, which enters through the nose, principally affecting the Lung. Therefore, they emphasized treatment with Pungent Sweet Cooling Moistening[辛甘凉潤] method. 4. As the conservation of fluid and humor is the primordial concern in the treatment of Warm disease, they restricted release of the exterior with pungent-warm and purgation method. The purgation methods was used exclusively to decrease fever and preserve fluid and humor. 5. The only differentiating characteristics of Influenza A with seasonal influenza are vomiting and diarrhea. Case research revealed the possibility of these manifestations to be a mechanism of restoration. 6. TKM provides alimento prevention method like Mint Pear Porridge, mung bean, and etc also combination of herbal medicine. Also emphasized in the conservation of essence for the prevention of contagious diseases. Conclusions: TKM developed its unique way in understanding the pathogenesis, diagnosis, treatment, and prevention of contagious diseases and formed its independent scheme of Warm Disease. This knowledge in febrile contagious disease is relevant today in providing diverse treatment and prevention for influenza A.