• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.18-23
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• 2012

Highly pathogenic avian influenza virus (HPAIV) is already panzootic in poultry and caused a considerable economic loss in poultry industry. In addition, HPAIV continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Citra-$Kill^{(R)}$ composed to quaternary ammonium chloride and citric acid was investigated against avian influenza H9N2 virus (AIV). A virucidal efficacy was determined with the viability of AIV contacted with the disinfectant in the allantoic membrane of chicken embryos. Citra-$Kill^{(R)}$ and AIV was reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW condition, AIV was inactivated with 2,000 fold dilutions of Citra-$Kill^{(R)}$. When the antiviral effect on HW condition was evaluated, the antiviral activity of the disinfectant showed on 1,500 fold dilutions against AIV. With the investigation of the antiviral effect of the disinfectant on OM condition, AIV was inactivated on 500 fold dilutions of Citra-$Kill^{(R)}$. As Citra-$Kill^{(R)}$ possesses virucidal efficacy against AIV, the disinfectant solution can be used to limit the spread of animal viral diseases.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.3-6
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• 2000

Antimicrobial resistance has been a well-recognized problem ever since the introduction of penicillin into clinical use. History of antimicrobial development can be categorized based on the major antibiotics that had been developed against emerging resistant $pathogens^1$. In the first period from 1940 to 1960, penicillin was a dominating antibiotic called as a "magic bullet", although S.aureus armed with penicillinase led antimicrobial era to the second period in 1960s and 1970s. The second stage was characterized by broad-spectrum penicillins and early generation cephalosporins. During this period, nosocomial infections due to gram-negative bacilli became more prevalent, while those caused by S.aureus declined. A variety of new antimicrobial agents with distinct mechanism of action including new generation cephalosporins, monobactams, carbapenems, ${\beta}$-lactamase inhibitors, and quinolones characterized the third period from 1980s to 1990s. However, extensive use of wide variety of antibiotics in the community and hospitals has fueled the crisis in emerging antimicrobial resistance. Newly appeared drug-resistant Streptococcus pneumoniae (DRSP), vancomycin-resistant enterococci (VRE), extended-spectrum ${\beta}$-lactamase-producing Klebsiella, and VRSA have posed a serious threat in many parts of the world. Given the recent epidemiology of antimicrobial resistance and its clinical impact, there is no greater challenge related to emerging infections than the emergence of antibiotic resistance. Problems of antimicrobial resistance can be amplified by the fact that resistant clones or genes can spread within or between the species as well as to geographically distant areas which leads to a global concern$^2$. Antimicrobial resistance is primarily generated and promoted by increased use of antimicrobial agents. Unfortunately, as many as 50 % of prescriptions for antibiotics are reported to be inappropriate$^3$. Injudicious use of antibiotics even for viral upper respiratory infections is a universal phenomenon in every part of the world. The use of large quantities of antibiotics in the animal health industry and farming is another major factor contributing to selection of antibiotic resistance. In addition to these background factors, the tremendous increase in the immunocompromised hosts, popular use of invasive medical interventions, and increase in travel and mixing of human populations are contributing to the resurgence and spread of antimicrobial resistance$^4$. Antimicrobial resistance has critical impact on modem medicine both in clinical and economic aspect. Patients with previously treatable infections may have fatal outcome due to therapeutic failure that is unusual event no more. The potential economic impact of antimicrobial resistance is actually uncountable. With the increase in the problems of resistant organisms in the 21st century, however, additional health care costs for this problem must be enormously increasing.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.485-489
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• 2011

In previous reports, the treatment of Bacillus amyloliquefaciens strain EXTN-1 showed a broad diseasecontrolling spectrum to the plant diseases caused by viral, bacterial, and fungal pathogens as well as the promotion of plant growth. In mechanisms of EXTN-1, treatment of EXTN-1 increased oxidative burst in early stage and induced the expression of resistance genes, PR-1a, PDF1.2. Mechanism involved in induced systemic resistance by EXTN-1 was revealed as simultaneous activation of SA and JA or ethylene metabolic pathways. The purpose of this study was to determine whether B. amyloliquefaciens EXTN-1 has a similar effect on rice plant against Rice stripe tenuivirus (RSV) under greenhouse conditions. When rice seeds were soaked in B. amyloliquefaciens strain EXTN-1, rice plants showed significant systemic resistance against RSV as well as promoted growth. In the case of plant growth, in 30-day old plants treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 12.6%, 9.8%, and 16.0%, respectively confirming the effects of PGPR. When the induced systemic resistance to RSV was examined, in 20-day old plants were treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 8.4%, 10.9%, and 4.8%, respectively compared to the control. Induced systemic resistance was more prominent in susceptible cultivars - Chucheong and Ilpum compared to the resistant cultivar, Nakdong.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1326-1334
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• 2008

The prime-boost vaccination with DNA vaccine and recombinant viral vector has emerged as an effective prophylactic strategy to control infectious diseases. Here, we compared the protective immunities induced by multiple alternating immunizations with DNA vaccine (pCIgB) and replication-incompetent adenovirus (Ad-gB) expressing glycoprotein gB of pseudorabies virus (PrV). The platform of pCIgB-prime and Ad-gB-boost induced the most effective immune responses and provided protection against virulent PrV infection. However, priming with pCIgB prior to vaccinating animals by the DNA vaccine-prime and Ad-boost protocol provided neither effective immune responses nor protection against PrV. Similarly, boosting with Ad-gB following immunization with DNA vaccine-prime and Ad-boost showed no significant responses. Moreover, whereas the administration of Ad-gB for primary immunization induced Th2-type-biased immunity, priming with pCIgB induced Th1-type-biased immunity, as judged by the production of PrV-specific IgG isotypes and cytokine IFN-$\gamma$. These results indicate that the order and injection frequency of vaccine vehicles used for heterologous prime-boost vaccination affect the magnitude and nature of the immunity. Therefore, our demonstration implies that the prime-boost protocol should be carefully considered and selected to induce the desired immune responses.

• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.245-250
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• 1998

Tobacco mosaic virus(TMV) coat protein cDNA was transformed to Nicotiana tabacum cv. NC82 and the transgenic tobacco plants resistant to TMV infection were isolated in the next generation. The expression of TMV coat protein cDNA and genetic stability of the fifth generation of TMV resistant transgenic tobacco plants at the higher temperature were investigated. The TMV coat protein cDNA was amplified by genomic PCR in all the TMV resistant transgenic tobacco plants. The TMV coat protein expressed in the transgenic tobacco plants was detected at very low level by immunoblot hybridization. Even in tansgenic plants that showed the viral symptom only on very late sucker growth (delay type plants), the coat protein expression in the suckers was much less than that of susceptible tobacco infected with TMV. The TMV coat protein expressed in the transgenic tobacco plants was below 0.01% of total protein. Transcription and expression of the coat protein cDNA in delay type plants were observbed at high temperature (38$^{\circ}C$), and TMV replication was suppressed at both 28$^{\circ}C$ and 38$^{\circ}C$. This indicates that unlike the resistance conferred by 'N' gene. TMV resistance of transgenic tobacco plant won't break down at high temperature.

• Molecules and Cells
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• v.37 no.1
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• pp.66-73
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• 2014

Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-${\alpha}$/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatment-naive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ${\zeta}$ expression on $CD8^+$ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-$1^+$ cells were closely associated with the histological activity index in CHC. The TCR ${\zeta}$ chain was significantly downregulated on hepatic $CD8^+$ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ${\zeta}$ chain expression in $CD8^+$ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ${\zeta}$ chain expression.

• Journal of Life Science
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• v.29 no.7
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• pp.824-835
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• 2019

In recent decades, oncolytic viruses (OVs) have extensively been investigated as a potential cancer drug. Oncolytic viruses have primarily the unique advantage in the fact that they can only infect and destroy cancer cells. Secondary, oncolytic viruses induce the activation of specific adaptive immunity which targets tumor-associated antigens that were hidden during the initial cancer progression. In 2015, one genetically modified oncolytic virus, talimogene laherparepvec (T-VEC), was approved by the American Food and Drug Administration (FDA) for the treatment of melanoma. Currently, various oncolytic viruses are being investigated in clinical trials as monotherapy or in combination with preexistent cancer therapies like immunotherapy, radiotherapy or chemotherapy. The efficacy of oncolytic virotherapy relies on the balance between the induced anti-tumor immunity and the anti-viral response. Despite the revolutionary outcome, the development of oncolytic viruses for the treatment of cancer faces a number of obstacles such as delivery method, neutralizing antibodies and induction of antiviral immunity due to the complexity, variability and reactivity of tumors. Intratumoral administration has been successful reducing considerably solid tumors with no notable side effects unfortunately some tumors are not accessible (brain) and require a systemic administration of the oncolytic viruses. In order to overcome these hurdles, various strategies to enhance the efficacy of oncolytic viruses have been developed which include the insertion of transgenes or combination with immune-modulatory substances.

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.404-412
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• 2018

The influenza neuraminidase (NA, E.C. 3.2.1.18), an antiviral, has been the target of high pharmaceutical companies due to its essential role in viral replication cycle. Perilla frutescens (P. frutescens) is used in traditional Chinese medicine for various diseases, such as cold due to wind-cold, headache and cough. In this context, four major polyphenolic compounds including rosmarinic acid-3-O-glucoside (1), rosmarinic acid (2), luteolin (3), and apigenin (4) isolated from P. frutescens were evaluated for their inhibitory effect on recombinant virus H1N1 neuraminidase (rvH1N1 NA). Among the test compounds, rosmarinic acid and luteolin inhibited the rvH1N1 NA with an $IC_{50}$ of 46.7 and $8.4{\mu}M$, respectively. The inhibition kinetics analyzed by the Dixon plots indicated that rosmarinic acid and luteolin were noncompetitive inhibitors and that the inhibition constant, $K_I$, was established as 43.9 and $14.3{\mu}M$, respectively. In addition, 578 genetically diverse accessions and 39 cultivars of P. frutescens were analyzed using HPLC to characterize the diversity of polyphenolic composition and concentration. The individual and total compositions exhibited significant difference (P < 0.05), especially rosmarinic acid which was detected as the predominant metabolite in all accessions (58.8%) and cultivars (62.8%). Yeupsil and Sangback cultivars exhibited the highest rosmarinic acid ($3,393.5{\mu}g/g$) and luteolin ($383.3{\mu}g/g$) content respectively. YCPL177-2 with the high concentration ($889.8{\mu}g/g$) of luteolin may be used as a genetic resource for breeding elite cultivars.

• Korean Journal of Poultry Science
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• v.46 no.3
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• pp.185-191
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• 2019

Nucleoporin 210 (Nup210) is associated with several physiological processes including muscle and neural cell differentiation, autoimmune diseases, and peripheral T cell homeostasis. Chicken Nup210 (chNup210) gene was originally identified as one of the differentially expressed genes (DEGs) in the kidney tissues of chicken. To elucidate the role of Nup210 in metabolic disease of chicken, we studied the molecular characteristics of chNup210 and analyzed its gene expression under the stimulation of Toll-like receptor 3 (TLR3) ligands. The Nup210 genomic DNA and amino acid sequences of various species including fowls, fishes, and mammals were retrieved from the Ensemble database and subjected to bioinformatics analyses. The expression of Nup210 from several chicken tissues was probed through qRT-PCR, and chicken fibroblast DF-1 cell line was used to determine the change in expression of chNup210 after stimulation with TLR3 ligand, polyinosinic-polycytidylic acid (poly (I:C)). The chNup210 gene was highly expressed in chicken lung and spleen tissues. Although highly conserved among the species, chNup210 was evolutionary clustered in the same clade as that of duck compared to other mammals. Furthermore, this study revealed that chNup210 is expressed in TLR3 signaling pathway and provides fundamental information on Nup210 expression in chicken. Future studies that offer insight into the involvement of chNup210 in the chicken innate immune response against viral infection are recommended.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.297-309
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• 2020

Coronaviruses were originally discovered as enzootic infections that limited to their natural animal hosts, but some strains have since crossed the animal-human species barrier and progressed to establish zoonotic diseases. Accordingly, cross-species barrier jumps resulted in the appearance of SARS-CoV, MERS-CoV, and SARS-CoV-2 that manifest as virulent human viruses. Coronaviruses contain four main structural proteins: spike, membrane, envelope, and nucleocapsid protein. The replication cycle is as follows: cell entry, genome translation, replication, assembly, and release. They were not considered highly pathogenic to humans until the outbreaks of SARS-CoV in 2002 in Guangdong province, China. The consequent outbreak of SARS in 2002 led to an epidemic with 8,422 cases, and a reported worldwide mortality rate of 11%. MERS-CoVs is highly related to camel CoVs. In 2019, a cluster of patients infected with 2019-nCoV was identified in an outbreak in Wuhan, China, and soon spread worldwide. 2019-nCoV is transmitted through the respiratory tract and then induced pneumonia. Molecular diagnosis based on upper respiratory region swabs is used for confirmation of this virus. This review examines the structure and genomic makeup of the viruses as well as the life cycle, diagnosis, and potential therapy.