• 대한수의학회지
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• 제53권4호
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• pp.193-197
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• 2013

Avian influenza viruses (AIV) have been isolated from a wide range of domestic and wild birds. Wild birds, predominantly ducks, geese and gulls form the reservoir of AIV in nature. The viruses in wild bird populations are a potential source of widespread infections in poultry. Active surveillance for AIV infection provides information regarding AIV distribution, and global AIV surveillance can play a key role in the early recognition of highly pathogenic avian influenza (HPAI). Since 2003 in Korea, there have been four H5N1 HPAI outbreaks caused by clade 2.5, 2.2 and 2.3.2. Therefore, improvement of AIV surveillance strategy is required to detect HPAI viruses effectively. This article deals with the major events establishing the role of wild birds in the natural history of influenza in Korea. We highlighted the need for continuous surveillance in wild birds and characterization of these viruses to understand AIV epidemiology and host ecology in Korea.

• Clinical and Experimental Vaccine Research
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• 제12권2호
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• pp.156-171
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• 2023

Purpose: The development of vaccines that confer protection against multiple avian influenza A (AIA) virus strains is necessary to prevent the emergence of highly infectious strains that may result in more severe outbreaks. Thus, this study applied reverse vaccinology approach in strategically constructing messenger RNA (mRNA) vaccine construct against avian influenza A (mVAIA) to induce cross-protection while targeting diverse AIA virulence factors. Materials and Methods: Immunoinformatics tools and databases were utilized to identify conserved experimentally validated AIA epitopes. CD8⁺ epitopes were docked with dominant chicken major histocompatibility complexes (MHCs) to evaluate complex formation. Conserved epitopes were adjoined in the optimized mVAIA sequence for efficient expression in Gallus gallus. Signal sequence for targeted secretory expression was included. Physicochemical properties, antigenicity, toxicity, and potential cross-reactivity were assessed. The tertiary structure of its protein sequence was modeled and validated in silico to investigate the accessibility of adjoined B-cell epitope. Potential immune responses were also simulated in C-ImmSim. Results: Eighteen experimentally validated epitopes were found conserved (Shannon index <2.0) in the study. These include one B-cell (SLLTEVETPIRNEWGCR) and 17 CD8⁺ epitopes, adjoined in a single mRNA construct. The CD8⁺ epitopes docked favorably with MHC peptidebinding groove, which were further supported by the acceptable ∆G_bind (-28.45 to -40.59 kJ/mol) and Kd (<1.00) values. The incorporated Sec/SPI (secretory/signal peptidase I) cleavage site was also recognized with a high probability (0.964814). Adjoined B-cell epitope was found within the disordered and accessible regions of the vaccine. Immune simulation results projected cytokine production, lymphocyte activation, and memory cell generation after the 1st dose of mVAIA. Conclusion: Results suggest that mVAIA possesses stability, safety, and immunogenicity. In vitro and in vivo confirmation in subsequent studies are anticipated.

• 대한한방내과학회지
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• 제30권3호
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• pp.558-570
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• 2009

Background : Since March 2009, when the first patient of novel influenza A (H1N1) was reported, many deaths have occurred in North and Central America. The start of the 2009 influenza pandemic was declared by WHO Director-General Dr. Margaret Chan on 11 June 2009, and the level of influenza pandemic alert raised from phase 5 to phase 6. There was no vaccine yet developed, and many experts worried that the novel H1N1 virus could kill as many or more as did the influenza pandemic in 1918-1919. Objective : To evaluate the possibility of treatment for 2009 novel influenza A (H1N1) using herbal remedies and other non-conventional therapies. Methods : We researched the clinical studies for novel H1N1 influenza virus-related herbal medicine or non-conventional medicine treatment using internet search engines including PubMed and CNKI. In addition, we reviewed many reports and clinical practice guidelines (CPG) for influenza A (H1N1). Results : Two case series were selected after reviewing 701 papers, and two CPG published by the Chinese government and Jilin province identified. They reported that the clinical symptoms were no more significant than seasonal influenza, and the condition of patients more than 45 years old was milder than those less than 45 years old. There are no patients with gastric problems, and oseltamivir has been used at the same time in all patients. Conclusion : The efficacy and effectiveness of herbal medicine and other non-conventional treatments for the novel influenza A (H1N1) is questionable, and more studies are needed to draw a firm conclusion. However, in the severe acute respiratory syndrome (SARS) experience in 2002/2003, it was demonstrated that herbal medicine can relieve all symptoms of SARS patients, promote absorption of lung inflammation, improve the degree of blood oxygen saturation, regulate immunological functions, reduce the required dosage of glucocorticoid and other medicines, and reduce case fatality rate. In light of the current situation that there is no vaccine or conventional treatment yet available, the study of herbal medicine and other non-conventional therapies are also necessary for appropriate evaluation.

• Genomics & Informatics
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• 제14권3호
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• pp.96-103
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• 2016

The influenza A (H1N1) virus, also known as swine flu is a leading cause of morbidity and mortality since 2009. There is a need to explore novel anti-viral drugs for overcoming the epidemics. Traditionally, different plant extracts of garlic, ginger, kalmegh, ajwain, green tea, turmeric, menthe, tulsi, etc. have been used as hopeful source of prevention and treatment of human influenza. The H1N1 virus contains an important glycoprotein, known as neuraminidase (NA) that is mainly responsible for initiation of viral infection and is essential for the life cycle of H1N1. It is responsible for sialic acid cleavage from glycans of the infected cell. We employed amino acid sequence of H1N1 NA to predict the tertiary structure using Phyre2 server and validated using ProCheck, ProSA, ProQ, and ERRAT server. Further, the modelled structure was docked with thirteen natural compounds of plant origin using AutoDock4.2. Most of the natural compounds showed effective inhibitory activity against H1N1 NA in binding condition. This study also highlights interaction of these natural inhibitors with amino residues of NA protein. Furthermore, among 13 natural compounds, theaflavin, found in green tea, was observed to inhibit H1N1 NA proteins strongly supported by lowest docking energy. Hence, it may be of interest to consider theaflavin for further in vitro and in vivo evaluation.

• Journal of Animal Science and Technology
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• 제65권4호
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• pp.838-855
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• 2023

The highly pathogenic avian influenza (HPAI) virus triggers infectious diseases, resulting in pulmonary damage and high mortality in domestic poultry worldwide. This study aimed to analyze miRNA expression profiles after infection with the HPAI H5N1 virus in resistant and susceptible lines of Ri chickens.For this purpose, resistant and susceptible lines of Vietnamese Ri chicken were used based on the A/G allele of Mx and BF2 genes. These genes are responsible for innate antiviral activity and were selected to determine differentially expressed (DE) miRNAs in HPAI-infected chicken lines using small RNA sequencing. A total of 44 miRNAs were DE after 3 days of infection with the H5N1 virus. Computational program analysis indicated the candidate target genes for DE miRNAs to possess significant functions related to cytokines, chemokines, MAPK signaling pathway, ErBb signaling pathway, and Wnt signaling pathway. Several DE miRNA-mRNA matches were suggested to play crucial roles in mediating immune functions against viral evasion. These results revealed the potential regulatory roles of miRNAs in the immune response of the two Ri chicken lines against HPAI H5N1 virus infection in the lungs.

• Pediatric Infection and Vaccine
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• 제9권2호
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• pp.193-200
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• 2002

목 적 : 바이러스에 의한 급성 하기도염은 병원에 입원하게 되는 가장 흔한 질병으로 이를 진단하는데는 역학적 진단이 절대적으로 중요하다. 이에 저자들은 서로 다른 두 지역에서의 바이러스성 급성 하기도염의 역학조사를 시행함으로써 지역간의 차이를 알아보고자 하였다. 방 법 : 2000년 6월부터 2001년 6월까지 마산 파티마병원과 삼성서울병원에 급성 하기도염으로 입원한 환자 796명을 대상으로 하였으며, 바이러스 검출은 비인두 분비물을 통해 시행하였다. 두 병원간 원인 바이러스, 연령분포, 임상증상, 계절 유행양상 등을 비교하였다. 결 과 : 1) 바이러스가 배양된 환아는 208명(26.1%)였다. 바이러스 검출율은 삼성서울병원 21.9%, 마산 파티마병원 30.0%였다. 삼성서울병원에서의 연령분포는 2세 이하의 환아가 60.2%였으며 5세 이상의 환아는 12.8%이었는데 비해 마산 파티마병원에서는 2세 이하의 환아가 90.0%였으며 5세 이상의 환자는 0.8%였다(P<0.05). 2) 마산 파티마병원에서는 RSV의 검출율이 높았고(72.3%), 삼성서울병원에서는 adenovirus, influenza type A와 parainfluenza virus의 검출율이 상대적으로 높았다(P<0.05). 3) 임상양상을 비교해 보면 삼성서울병원에서는 기관기관지염과 폐렴이, 마산 파티마병원에서는 모세기관지염과 크룹이 더 많은 비율을 차지하고 있었다(P<0.05). 두 병원 모두 모세기관지염은 RSV, 크룹은 parainfluenza virus가 가장 많았다. 폐렴의 경우 삼성서울병원에서는 adenovirus, 마산 파티마병원은 RSV가 가장 많았고, 기관기관지염의 경우 삼성서울병원에서는 adenovirus, 마산 파티마병원은 influenza virus-type A가 가장 많았다. 4) 두 병원 모두 RSV는 가을과 겨울, parainfluenza virus는 봄, influenza virus는 겨울과 봄에 나타나는 양상을 보였고 adeonvirus는 연중 발생하는 양상을 보였다. 결 론 : 두 병원의 바이러스의 유행시기, 임상양상에 따른 원인바이러스의 분포결과는 유사하였다. 각 바이러스의 검출률과 임상상의 분포 등에서는 차이를 보였는데 이는 지역적 차이보다는 주로 대상연령군의 차이에 기인하는 것으로 생각된다. 우리나라에서 바이러스성 호흡기감염의 지역적 차이 유무를 확인하기 위해서는 비슷한 연령군을 대상으로 한 전국적이고 지속적인 역학조사가 이루어져야 할 것으로 사료된다.

• 한국임상약학회지
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• 제13권1호
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• pp.5-12
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• 2003

Influenza virus is a major cause of respiratory infection in the epidemic season. Especially, the elderly with underlying health problems are at increased risk for complications of influenza. The objective of this study was to investigate that influenza vaccination can reduce the hospital admission rate related to the respiratory diseases. This study was a retrospective study of two age groups, who are the healthy children aged 6 months to 9 years (n=237) and the adults aged over 20 years with respiratory disease (n=327). The vaccinated groups were compared to the controls that were matched in sex and age. The children were vaccinated in winter season of 1995-96 and the adults were vaccinated in 1996-97. The efficacy of influenza vaccine was evaluated with the number of outpatient visits in children group, the admission rate and the mean admission days in both children and adult group. As results, there were not significant differences between the vaccinated and the control group of children. In the elderly over 61 years, however, the influenza vaccination can reduce the admission rate $(8.9\%\;vs.\;25.6\%,\;p<0.05)$ and the mean admission days (1.3 vs. 3.8 days, p<0.05) compared to the control. In conclusion, influenza vaccination can effectively reduce the events related to respiratory infection in the elderly than the children. The elderly should be recommended for influenza vaccination.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.735-745
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• 2024

Avian influenza is a serious threat to both public health and the poultry industry worldwide. This respiratory virus can be combated by eliciting robust immune responses at the site of infection through mucosal immunization. Recombinant probiotics, specifically lactic acid bacteria, are safe and effective carriers for mucosal vaccines. In this study, we engineered recombinant fusion protein by fusing the hemagglutinin 1 (HA1) subunit of the A/Aquatic bird/Korea/W81/2005 (H5N2) with the Bacillus subtilis poly γ-glutamic acid synthetase A (pgsA) at the surface of Lactobacillus casei (pgsA-HA1/L. casei). Using subcellular fractionation and flow cytometry we confirmed the surface localization of this fusion protein. Mucosal administration of pgsA-HA1/L. casei in mice resulted in significant levels of HA1-specific serum IgG, mucosal IgA and neutralizing antibodies against the H5N2 virus. Additionally, pgsA-HA1/L. casei-induced systemic and local cell-mediated immune responses specific to HA1, as evidenced by an increased number of IFN-γ and IL-4 secreting cells in the spleens and higher levels of IL-4 in the local lymphocyte supernatants. Finally, mice inoculated with pgsA-HA1/L. casei were protected against a 10LD50 dose of the homologous mouse-adapted H5N2 virus. These results suggest that mucosal immunization with L. casei displaying HA1 on its surface could be a potential strategy for developing a mucosal vaccine against other H5 subtype viruses.

• Journal of Veterinary Science
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• 제23권3호
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• pp.36.1-36.14
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• 2022

Background: Since 2003, the H5 highly pathogenic avian influenza (HPAI) subtype has caused massive economic losses in the poultry industry in South Korea. The role of inland water bodies in avian influenza (AI) outbreaks has not been investigated. Identifying water bodies that facilitate risk pathways leading to the incursion of the HPAI virus (HPAIV) into poultry farms is essential for implementing specific precautionary measures to prevent viral transmission. Objectives: This matched case-control study (1:4) examined whether inland waters were associated with a higher risk of AI outbreaks in the neighboring poultry farms. Methods: Rivers, irrigation canals, lakes, and ponds were considered inland water bodies. The cases and controls were chosen based on the matching criteria. The nearest possible farms located within a radius of 3 km of the case farms were chosen as the control farms. The poultry farms were selected randomly, and two HPAI epidemics (H5N8 [2014-2016] and H5N6 [2016-2017]) were studied. Conditional logistic regression analysis was applied. Results: Statistical analysis revealed that inland waters near poultry farms were significant risk factors for AI outbreaks. The study speculated that freely wandering wild waterfowl and small animals contaminate areas surrounding poultry farms. Conclusions: Pet birds and animals raised alongside poultry birds on farm premises may wander easily to nearby waters, potentially increasing the risk of AI infection in poultry farms. Mechanical transmission of the AI virus occurs when poultry farm workers or visitors come into contact with infected water bodies or their surroundings. To prevent AI outbreaks in the future, poultry farms should adopt strict precautions to avoid contact with nearby water bodies and their surroundings.

• Tuberculosis and Respiratory Diseases
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• 제80권4호
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• pp.392-400
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• 2017

Background: Most patients with influenza recover spontaneously or following treatment with an anti-viral agent, but some patients experience pneumonia requiring hospitalization. We conducted a retrospective review to determine the incidence and risk factors of pneumonia in hospitalized patients with influenza A or B. Methods: A total of 213 patients aged 18 years or older and hospitalized with influenza between January 2012 and January 2015 were included in this study. A reverse-transcriptase polymerase chain reaction assay was used to detect the influenza A or B virus in the patients' sputum samples. We collected demographic and laboratory data, combined coexisting diseases, and radiologic findings. Results: The incidence of pneumonia was higher in patients in the influenza A group compared to those in the influenza B group (68.6% vs. 56.9%), but this difference was not statistically significant. The presence of underlying respiratory disease was significantly associated with pneumonia in the influenza A group (adjusted odds ratio [OR], 3.975; 95% confidence interval [CI], 1.312-12.043; p=0.015). In the influenza B group, the white blood cell count (adjusted OR, 1.413; 95% CI, 1.053-1.896; p=0.021), platelet count (adjusted OR, 0.988; 95% CI, 0.978-0.999; p=0.027), and existence of an underlying medical disease (adjusted OR, 15.858; 95% CI, 1.757-143.088; p=0.014) were all significantly associated with pneumonia in multivariate analyses. Conclusion: The incidence of pneumonia was 65.7% in hospitalized patients with influenza A or B. The risk factors of pneumonia differed in hospitalized patients with influenza A or B.