• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.373-378
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• 2005

Influenza virus has a unique characteristics of annual epidemics of acute respiratory disease with attack rate of 10%-30% of the population. It is also the classical emerging infectious disease causing global pandemics when new antigenic shift occur. This antigenic shift is the key to its ability to evoke periodic pandemics, and it has caused at least 3 pandemics in 20th century. I reviewed these 3 pandemics in their natural courses and the epidemiology of the recent emerging influenza A viruses, especially the H5 and H7 subtypes. I descr ibed the epidemics of these vi ruses in human population and why we should be prepared to these viruses.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.347-348
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• 2023

Vaccines help protect people from infections. However, Coronavirus 2019 (COVID-19) vaccinees often still become infected with COVID-19 variants (breakthrough infections) and may go on to suffer from long COVID symptoms due to short-lasting immunity and less-effective protection provided by available vaccines. Moreover, the current COVID-19 vaccines do not prevent viral transmission and ward off only about 15% of breakthrough infections. To prepare more effective vaccines, it is essential to predict the viral strains that will be circulating based on available epidemiological data. The World Health Organization recommends in advance which influenza strains are expected to be prevalent during influenza season to guide the production of influenza vaccines by pharmaceutical companies. However, future emerging COVID-19 strain(s) have not been possible to predict since no sound epidemiological information has been established. Thus, for more effective protection, immune stimulators alone or in combination with vaccines would be preferable to protect people from COVID-19 infection. One of those remedies would be ginseng, which has been used for potentiating immunity in the past.

• Journal of Life Science
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• v.33 no.8
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• pp.605-611
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• 2023

Recently, sporadic cases of human infection by genetic reassortants of H7Nx influenza A viruses have been reported; such viruses have also been continuously isolated from avian species. In this study, A/wild bird/South Korea/sw-anu/2023, a novel reassortant of the H7N1 avian influenza virus, was analyzed using full-genome sequencing and molecular characterization. Phylogenetic analysis showed that A/wild bird/South Korea/sw-anu/2023 belonged to the Eurasian lineage of H7Nx viruses. The polymerase basic (PB)2, PB1, polymerase acidic (PA), and nucleoprotein (NP) genes of these viruses were found to be closely related to those of avian influenza viruses isolated from wild birds, while the hemagglutinin (HA), neuraminidase (NA), matrix (M), and nonstructural (NS) genes were similar to those of avian influenza viruses isolated from domestic ducks. In addition, A/wild bird/South Korea/sw-anu/2023 also had a high binding preference for avian-specific glycans in the solid-phase direct binding assay. These results suggest the presence of a new generation of H7N1 avian influenza viruses in wild birds and highlight the reassortment of avian influenza viruses found along the East Asian-Australasian flyway. Overall, H7Nx viruses circulate worldwide, and mutated H7N1 avian viruses may infect humans, which emphasizes the requirement for continued surveillance of the H7N1 avian influenza virus in wild birds and poultry.

• Journal of Sensor Science and Technology
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• v.23 no.4
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• pp.278-283
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• 2014

In this study, we propose an immunosensor using zinc oxide nanorods (NRs) inside PDMS channel for detecting the influenza A virus subtype H7N9. ZnO with high isoelectric point (IEP, ~9.5) makes it suitable for immobilizing proteins with low IEP. In this proposed H7N9 immunosensor structure ZnO NRs were grown on the PDMS channel inner surface to immobilize H7N9 capture antibody. A sandwich enzyme-linked immunosorbent assay (ELISA) method with was used 3,3',5,5' tetramethylbenzidine (TMB) for detecting H7N9 influenza virus. The immunosensor was evaluated by amperometry at various H7N9 influenza antigen concentrations (1 pg/ml - 1 ng/ml). The redox peak voltage and current were measured by amperometry with ZnO NWs and without ZnO NWs inside PDMS channel. The measurement results of the H7N9 immunosensor showed that oxidation peak current of TMB at 0.25 V logarithmically increased from 2.3 to 3.8 uA as the H7N9 influenza antigen concentration changed from 1 pg/ml to 1 ng/ml. And then we demonstrated that ZnO NRs inside PDMS channel can improve the sensitivity of immunosensor to compare non-ZnO NRs inside PDMS channel.

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1164-1169
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• 2008

We developed multiplex RT-PCR assays that can detect and identify 12 hemagglutinin (H1-H12) and 9 neuraminidase (N1-N9) subtypes that are commonly isolated from avian, swine, and human influenza A viruses. RT-PCR products with unique sizes characteristic of each subtype were amplified by multiplex RT-PCRs, and sequence analysis of each amplicon was demonstrated to be specific for each subtype with 24 reference viruses. The specificity was demonstrated further with DNA or cDNA templates from 7 viruses, 5 bacteria, and 50 influenza A virus-negative specimens. Furthermore, the assays could detect and subtype up to $10^5$ dilution of each of the reference viruses that had an original infectivity titer of $10^6\;EID_{50}/ml$. Of 188 virus isolates, the multiplex RT-PCR results agreed completely with individual RT-PCR subtyping results and with results obtained from virus isolations. Furthermore, the multiplex RT-PCR methods efficiently detected mixed infections with at least two different subtypes of influenza viruses in one host. Therefore, these methods could facilitate rapid and accurate subtyping of influenza A viruses directly from field specimens.

• Journal of Microbiology and Biotechnology
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• v.27 no.11
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• pp.2037-2043
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• 2017

The surface protein hemagglutinin (HA) mediates the attachment of influenza virus to host cells containing sialic acid and thus facilitates viral infection. Therefore, HA is considered as a good target for the development of diagnostic tools for influenza virus. Previously, we reported the isolation of single-stranded aptamers that can distinguish influenza subtype H1 from H5. In this study, we describe a method for the selective electrical detection of H1 using the isolated aptamer as a molecular probe. After immobilization of the aptamer on Si wafer, enzyme-linked immunosorbent assay (ELISA) and field emission scanning electron microscopy (FE-SEM) showed that the immobilized aptamer bound specifically to the H1 subtype but not to the H5 subtype. Assessment by cyclic voltammetry (CV) also demonstrated that the immobilized aptamer on the indium thin oxide-coated surface was specifically bound to the H1 subtype only, which was consistent with the ELISA and FE-SEM results. Further measurement of CV using various amounts of H1 subtype provided the detection limit of the immobilized aptamer, which showed that a nanomolar scale of target protein was sufficient to produce the signal. These results indicated that the selected aptamer can be an effective probe for distinguishing the subtypes of influenza viruses by monitoring current changes.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.151-159
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• 2016

Nanoparticles have wide-scale applications in various areas, including medicine, chemistry, electronics, and energy generation. Several physical, biological, and chemical methods have been used for synthesis of silver nanoparticles. Green synthesis of silver nanoparticles using plants provide advantages over other methods as it is easy, efficient, and eco-friendly. Nanoparticles have been extensively studied as potential antimicrobials to target pathogenic and multidrug-resistant microorganisms. Their applications recently extended to development of antivirals to inhibit viral infections. In this study, we synthesized silver nanoparticles using Cinnamomum cassia (Cinnamon) and evaluated their activity against highly pathogenic avian influenza virus subtype H7N3. The synthesized nanoparticles were characterized using UVVis absorption spectroscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. Cinnamon bark extract and its nanoparticles were tested against H7N3 influenza A virus in Vero cells and the viability of cells was determined by tetrazolium dye (MTT) assay. The silver nanoparticles derived from Cinnamon extract enhanced the antiviral activity and were found to be effective in both treatments, when incubated with the virus prior to infection and introduced to cells after infection. In order to establish the safety profile, Cinnamon and its corresponding nanoparticles were tested for their cytotoxic effects in Vero cells. The tested concentrations of extract and nanoparticles (up to 500 μg/ml) were found non-toxic to Vero cells. The biosynthesized nanoparticles may, hence, be a promising approach to provide treatment against influenza virus infections.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.243-252
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• 2013

Among the 16 hemagglutinin (HA) subtypes of avian influenza virus (AIV), only the H5 and H7 subtypes have caused highly pathogenic avian influenza (HPAI) in poultry. However, most H5 or H7 subtype viruses are categorized as low pathogenic avian influenza (LPAI). Some AIVs, including the H5 and H7 HPAI viruses, have shown the ability to infect humans directly. In this study, we describe the biological and molecular characterization of an H5N3 AIV (SBD/KR/KNU SYG06/06) isolated from spot-billed duck (Anas poecilorhyncha) in Korea. A phylogenetic analysis of the eight viral genes showed that the SBD/KR/KNU SYG06/06 isolate belongs to the Eurasian lineage and that the SBD/KR/KNU SYG06/06 isolate was clearly different from HPAI H5N1 strains, including human isolates and the Italian HPAI H5N2 strains. Additionally, no relationship was found between SBD/KR/KNU SYG06/06 and the Korean HPAI H5N1 isolates. The SBD/KR/ KNU SYG06/06 isolate had avian specific receptor binding site residues in the HA protein and the four C-terminal amino acids in the NS1 protein. The HA protein of the SBD/KR/KNU SYG06/06 isolate exhibited the typical LPAI motif at the cleavage site and this virus produced no cytopathic effects in MDCK cells without trypsin. Given these results, we suggest that the H5N3 AIV isolated from the spot-billed duck should be considered an LPAI virus and should have no pathogenic effect in humans.

• Childhood Kidney Diseases
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• v.21 no.2
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• pp.89-93
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• 2017

Purpose: Virus-associated rhabdomyolysis is very rare. We report 15 patients with rhabdomyolysis caused by various viruses. Methods: Fifteen patients who were diagnosed with rhabdomyolysis and a viral infection were included in this study. Clinical, laboratory, and radiologic findings were evaluated through retrospective chart reviews. Results: Chief complaints were severe bilateral lower leg pain and leg weakness. The median age was 5.7 years. The male:female ratio was 2:5. The viral infections were caused by influenza virus B, parainfluenza virus, and rhinovirus. One patient with influenza virus B had coinfection with coronavirus. Median initial laboratory values and ranges were as follows: serum creatinine, 0.4 (0.1-0.5) mg/dL; serum aspartate transaminase, 124 (48-1,098) IU/L; serum alanine transaminase, 30 (16- 1,455) IU/L; serum creatine kinase, 2,965 (672-16,594) IU; serum lactate dehydrogenase, 400 (269-7,394) IU/L; serum myoglobin, 644 (314-3,867) ng/mL; urine myoglobin, 3 (3-10,431) ng/mL. All patients recovered without complications. Conclusion: This is the first report of the simultaneous occurrence of rhabdomyolysis caused by various viruses. This is also the first report of rhinovirus-associated rhabdomyolysis.

• 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.