• Journal of the Korean Electrochemical Society
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• v.26 no.4
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• pp.43-55
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• 2023

Mass transport through nanoporous structures such as nanopores or nanochannels has fundamental electrochemical implications and many potential applications as well. These structures can be particularly useful for water treatment, energy conversion, biosensing, and controlled delivery of substances. Earlier research focused on creating nanopores with diameters ranging from tens to hundreds of nanometers that can selectively transport cationic or anionic charged species. However, recent studies have shown that nanopores with diameters of a few nanometers or even less can achieve more complex and versatile transport control. For example, nanopores that mimic biological channels can be functionalized with specific receptors to detect viruses, small molecules, and even ions, or can be made hydrophobic and responsive to external stimuli, such as light and electric field, to act as efficient valves. This review summarizes the latest developments in nanopore-based systems that can control mass transport based on the size of the nanopores (e.g., length, diameter, and shape) and the physical/chemical properties of their inner surfaces. It also provides some examples of practical applications of these systems.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.81-81
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• 2020

Pneumonia is infection of air sacs in lungs by bacteria, viruses, fungi and abnormal atmosphere condition. That causes to inflammation and fills up with pus and fulid in air sacs. The symptoms of pneumonia are heavy cough, fever, shortness and rapid respiration and sputum with blood. Also, that remains sequela after the recovery. Thymus quinquecostatus (TQ) has a strong antibacterial effect. That has been used a natural medicine for bronchitis, asthma and nervous inflammation. In this study evaluated anti-inflammatory effects of TQ on IFN (interferon)-γ/TNF (tumor necrosis factor)-α (20 ng/ml) stimulation. MRC-5 cells were seeded at 1 × 10⁵ cells/well in a 24-well plate and stabilized overnight at 37℃. The cells were treated with various concentrations of TQ extracts (DW, 30, 50, 70, 95% EtOH, 0.1~100 mg/ml) for 4h, Subsequently IFN-γ/TNF-α (20 ng/ml) was added to each well and incubated over 12h. the production of inflammatory cytokines were measured by Enzyme-linked immunosorbentassay(ELISA) method. The absorbance was measured at 450 nm using microplate reader. The treatment with TQ extract at dose of 0.1 to 100 mg/ml did not show cytotoxicity in MRC-5 cells (showed cytotoxicity at 95% EtOH 100 mg/ml). The results demonstrated that stimulation of TNF-α/IFN-γ significantly increased the production of inflammatory mediators in the MRC-5 cells compared with unstimulated cells. By contrast, treatment with TQ extreats doses of 0.001 to 10 mM significantly suppressed the production of IL-6 and IL-8. Especially. The higher percent of ethyl alcohol extracts suppressed the production of inflammatory cytokines. This results are considered that essential oil of TQ is extracted according to ethyl alcohol percent. Therefore, TQ has potential to mitigate pulmonary disease that can be used a medicine for pneumonia

• Korean Journal of Veterinary Service
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• v.46 no.4
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• pp.269-281
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• 2023

In this study, a new triplex real-time quantitative reverse transcription polymerase chain reaction (tqRT-PCR) assay was developed for the rapid and differential detection of three feline viral pathogens including feline calicivirus (FCV), feline herpesvirus 1 (FHV-1), and influenza A virus (IAV) in a single reaction. The assay specifically amplified three targeted viral genes with a detection limit of below 10 copies/reaction. The assay showed high repeatability and reproducibility, with intra- and inter-assay coefficients of variation of less than 1%. Based on the diagnostic results of the assay using 120 clinical samples obtained from cats with feline respiratory disease complex (FRDC)-suspected signs, the prevalence of FCV, FHV-1, or IAV was 43.3%, 22.5%, or 0%, respectively, indicating that the diagnostic sensitivity was comparable or superior to those of previously reported monoplex qRT-PCR/qPCR assays. The dual infection rate for FCV and FHV-1 was 8.3%. These results indicate that FCV and FHV-1 are widespread and that co-infection with FCV and FHV-1 frequently occur in the Korean cat population. The developed tqRT-PCR assay will serve as a promising tool for etiological and epidemiological studies of these three bacterial pathogens, and the prevalence data for three feline viruses obtained in this study will contribute to expanding knowledge about the epidemiology of FRDC in the current Korean cat population.

• The Plant Pathology Journal
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• v.40 no.1
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• pp.73-82
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• 2024

Gardenia (Gardenia jasminoides) is a popular and economically vital plant known for its ornamental and medicinal properties. Despite its widespread cultivation, there has been no documentation of plant viruses on gardenia yet. In the present study, gardenia leaves exhibiting symptoms of plant viral diseases were sampled and sequenced by both metatranscriptome and small RNA sequencing. As a consequence, bean common mosaic virus (BCMV) was identified in gardenia for the first time and named BCMV-gardenia. The full genome sequence of BCMV-gardenia is 10,054 nucleotides (nt) in length (excluding the poly (A) at the 3' termini), encoding a large polyprotein of 3,222 amino acids. Sequence analysis showed that the N-termini of the polyprotein encoded by BCMV-gardenia is less conserved when compared to other BCMV isolates, whereas the C-termini is the most conserved. Maximum likelihood phylogenetic analysis showed that BCMVgardenia was clustered closely with other BCMV isolates identified outside the leguminous plants. Our results indicated that the majority of BCMV-gardenia virus-derived small interfering RNAs (vsiRNAs) were 21 nt and 22 nt, with 21 nt being more abundant. The first nucleotide at the 5' termini of vsiRNAs derived from BCMV-gardenia preferred U and A. The ratio of vsiRNAs derived from sense (51.1%) and antisense (48.9%) strands is approaching, and the distribution of vsiRNAs along the viral genome is generally even, with some hot spots forming in local regions. Our findings could provide new insights into the diversity, evolution, and host expansion of BCMV and contribute to the prevention and treatment of this virus.

• Journal of Korea Water Resources Association
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• v.57 no.4
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• pp.277-287
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• 2024

Water distribution system (WDS) is exposed to various water quality incidents during its operation. This study utilized Quantitative Microbial Risk Assessment (QMRA) to analyze the risk associated with potential virus intrusion in WDSs. Additionally, the study determined the location and operation of rechlorination facilities to minimize potential risk. In addition, water quality resilience was calculated to confirm that the chlorine concentration maintains within the target range (0.1-1.0 mg/L) during normal operation. Hydraulic analysis was performed using EPANET, while EPANET-MSX was linked to simulate the reactions between viruses and chlorine. The proposed methodology was applied to the Bellingham network in the United States, where rechlorination facilities capable of injecting chlorine concentrations ranging from 0.5 mg/L to 1.0 mg/L were considered. Results indicated that without rechlorination facilities, the Average risk was 0.0154. However, installing rechlorination facilities and injecting chlorine at a concentration of 1.0 mg/L could reduce the Average risk to 39.1%. It was observed that excessive chlorine injection through rechlorination facilities reduced water quality resilience. Consequently, a rechlorination facility with a concentration of 0.5 mg/L was selected, resulting in a reduction of approximately 20% in average risk. This study provides insights for designing rechlorination facilities to enhance preparedness against potential virus ingress in the future.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.282-288
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• 2023

Due to the COVID-19 pandemic, the immuneenhancing health functional food market that protects our bodies from pathogens such as viruses continues to grow. In this study, we aimed to prove the Cheonggukjang, a high-nutrient food with high protein, fat, and dietary fiber content, as an immuneenhancing nutraceutical. Cheonggukjang water extract (CWE) increased the production of nitric oxide, reactive oxygen species, and cytokines such interleukin (IL)-6, IL-1β, and tumor necrosis factor-α without affecting viability in RAW 264.7 cells. Furthermore, CWE significantly upregulated the expression of inducible nitric oxide synthase and cyclooxygenase-2 in RAW 264.7 cells. CWE enhanced the phosphorylation of I kappa B kinase α/β and I kappa B (IκB)α, as well as the degradation of IκBα. CWE also induced increased phosphorylation of nuclear factor-kappa B p65 and facilitated the redistribution of p65 from the cytoplasm to the nucleus in RAW 264.7 cells. These findings suggest that CWE has potential as a health functional food material that can enhance the innate immune response.

• Biomolecules & Therapeutics
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• v.32 no.4
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• pp.481-491
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• 2024

Paxlovid is the first approved oral treatment for coronavirus disease 2019 and includes nirmatrelvir, a protease inhibitor targeting the main protease (M^pro) of SARS-CoV-2, as one of the key components. While some specific mutations emerged in M^pro were revealed to significantly reduce viral susceptibility to nirmatrelvir in vitro, there is no report regarding resistance to nirmatrelvir in patients and animal models for SARS-CoV-2 infection yet. We recently developed xenograft tumors derived from Calu-3 cells in immunodeficient mice and demonstrated extended replication of SARS-CoV-2 in the tumors. In this study, we investigated the effect of nirmatrelvir administration on SARS-CoV-2 replication. Treatment with nirmatrelvir after virus infection significantly reduced the replication of the parental SARS-CoV-2 and SARS-CoV-2 Omicron at 5 days post-infection (dpi). However, the virus titers were completely recovered at the time points of 15 and 30 dpi. The virus genomes in the tumors at 30 dpi were analyzed to investigate whether nirmatrelvir-resistant mutant viruses had emerged during the extended replication of SARS-CoV-2. Various mutations in several genes including ORF1ab, ORF3a, ORF7a, ORF7b, ORF8, and N occurred in the SARS-CoV-2 genome; however, no mutations were induced in the M^pro sequence by a single round of nirmatrelvir treatment, and none were observed even after two rounds of treatment. The parental SARS-CoV-2 and its sublineage isolates showed similar IC₅₀ values of nirmatrelvir in Vero E6 cells. Therefore, it is probable that inducing viral resistance to nirmatrelvir in vivo is challenging differently from in vitro passage.

• Journal of Sericultural and Entomological Science
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• v.25 no.2
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• pp.1-31
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• 1984

Flacherie, as one of the most prevalent silkworm diseases, causes severe economic damage to sericultural industry and its pathogens have been proved to be flacherie virus (FV) and densonucleosis virus (DNV). Multiplications of the viruses in the larvae of the silkworm, Bombyx mori, were studied by the sucrose density gradient centrifugation and electron microscopy. The quantitative and qualitative changes of nucleic acids and proteins were investigated from the midgut and hemolymph in the silkworm larvae infected separately with FV and DNV. The histopathological changes of epithelial cells of infected midgut also were examined by an electron microscope. 1. Purified fractions of FV or DNV in a sucrose density gradient centrifugation yielded one homogenous and sharp peak without a shoulder, suggesting no heterogenous materials in the preparation. Electron microscopy also revealed that FV and DNV were spherical particles, 27nm and 21nm in diameter, respectively. 2. Silkworm larvae showed a decrease in body weight on the 6th day and in midgut weight on the 3rd day after inoculation with FV or DNV. 3. DNA content was higher in the midgut when infected with FV or DNV, but the hemolymph of the infected larvae showed no difference during first 6 days after inoculation, after which DNA concentration declined rapidly. 4. RNA synthesis of silkworm larvae infected separately with FV and DNV was stimulated in the midgut, but RNA content was reduced in the hemolymph at the early stage of virus multiplication. At the late stage of virus multiplication, however, it was extremely reduced in both midgut and hemolymph. 5. The concentration of protein in the midgut and hemolymph of silkworm larvae infected separately with FV and DNV showed no difference from that of the healthy larvae at the early stage of virus multiplication, but it was significantly reduced at the late stage of virus multiplication. 6. There was no difference in the electrophoretic patterns of RNAs extracted from the midgut of healthy or virus-infected larvae. 7. The electrophoresis of proteins extracted from the midgut infected with FV or DNV, when carried out on the 1st and 5th day after virus inoculation, showed no difference from that of the healthy larvae. But, there was an additional band with medium motility in the proteins on the 8th day after virus inoculation, while a band with low mobility shown in the proteins of healthy larvae disappeared in the infected larvae. However, a band with high mobility in the healthy larvae was separated into two fractions in the infected larvae. 8. The electrophoretic pattern of hemolymph proteins of the silkworm larvae infected separately with FV and DNV was similar to that of the healthy larvae, but the concentration of hemolymph proteins in the infected larvae was lower than that of the healthy larvae at the late stage. 9. Two types of inclusion bodies were shown by the double staining of pyronin-methyl green in the columnar cell of the midgut on the 8th day after FV inoculation. 10. Electron microscopy of the infected midgut revealed that the 'cytoplasmic wall' of the goblet cell thickened on the 5th day after FV inoculation and several types of the cytopathogenic structures, such as virus$.$specific vesicles, virus particles, linear structures, tubular structures, and high electron-dense matrices were observed in the cytoplasm of the goblet cell. The virus particles were also observed in the microvilli and the structures similar to spherical virus particles were observed around the virus-specific vesicles, suggesting the virus assembly in the cytoplasm. 11. Fluorescence micrograph of the infected midgut stained with acridine orange showed that the nucleus, the site of DNV multiplication in the columnar cell, enlarged on the 5th day after virus inoculation. 12. Electron microscopic examination of DNV infected midgut revealed that the nucleolus of the columnar cell was broken into granules and those granules dispersed into apical region of the nucleus on the 5th day after virus inoculation. On the 8th day after inoculation, it was also observed that the nucleus of the columnar cell was full with the high electron-dense virogenic stroma which were similar to virus particles. These facts suggest that the virogenic stroma were the sites of virus assembly in the process of DNV multiplication.

• Journal of agricultural medicine and community health
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• v.30 no.2
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• pp.137-149
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• 2005

Objectives and Methods: This study was performed to investigate the etiologic bacterial, viral and protozoal organisms for the diarrhea from hospitals in Chungnam area from January to December in 2004. Total of 787 fecal samples were collected and examined. Results and Conclusions: In test for enteropathogenic bacteria, total of 79 cases out of 787 samples from hospitals showed positive isolation. Among 79 positive samples, 27 cases were confirmed as Salmonella spp.. 20 cases as pathogenic E. coli, 18 cases as Clostridium perfringens, 6 cases as Staphylococcus aureus, 4 cases as Shigella spp. and 4 cases as Vibrio parahaemolyticus. In test for enteropathogenic virus, 190 cases out of 787 samples from hospitals showed positive reaction. Among 190 samples, 115 cases were confirmed as rotavirus, 55 cases as norovirus, 5 case as astrovirus, 4 case as rotavirus & norovirus, 3 cases as adenovirus, 2 case as rotavirus & astrovirus. In test for enteropathogenic protozoa, 6 cases out of 787 samples from hospitals showed positive result. Among 6 samples, 5 cases were confirmed as Entamoeba histolytica and 1 cases as Giardia lamblia. When we classified the positive results by the age of the patients, the highest isolation rate was noted in a group of age under 10 and over 60 for bacterial, viral and protozoal pathogens. Especially, patient below age of 5 showed high positive rate. When we classified the positive results by the time, pageathogenic bacteria were isolated throughout the year, and the highest frequency was noted in August. On the other hand, pathogenic viruses were detected more frequently during the colder season from December to April. Antimicrobial susceptibility test for the isolated bacteria resulted as follows; Salmonella strains showed high drug resistance rates against ampicillin, chloramphenicol, tetracycline, nalidixic acid, ticarcillin. Shigella strains showed high drug resistance rates against ampicillin, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline, ampicillin/sulbactam, ticarcillin. Pathogenic E. coli strains showed high drug resistance rates against ampicillin, cephalothin, gentamicin, tetracycline, nalidixic acid, ampicillin/sulbactam, ticarcillin.