• Journal of Yeungnam Medical Science
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• v.37 no.4
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• pp.286-295
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• 2020

Respiratory infections are very common and highly contagious. Respiratory infectious diseases affect not only the person infected but also the family members and the society. As medical sciences advance, several diseases have been conquered; however, the impact of novel infectious diseases on the society is enormous. As the clinical presentation of respiratory infections is similar regardless of the pathogen, the causative agent is not distinguishable by symptoms alone. Moreover, it is difficult to develop a cure because of the various viral mutations. Various respiratory infectious diseases ranging from influenza, which threaten the health of mankind globally, to the coronavirus disease 2019, which resulted in a pandemic, exist. Contrary to human expectations that development in health care and improvement in hygiene will conquer infectious diseases, humankind's health and social systems are threatened by novel infectious diseases. Owing to the development of transport and trading activity, the rate of spread of new infectious diseases is increasing. As respiratory infections can threaten the members of the global community at any time, investigations on preventing the transmission of these diseases as well as development of effective antivirals and vaccines are of utmost importance and require a worldwide effort.

• Molecules and Cells
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• v.45 no.10
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• pp.702-717
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• 2022

Hepatitis C virus (HCV) infection can lead to chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV employs diverse strategies to evade host antiviral innate immune responses to mediate a persistent infection. In the present study, we show that nonstructural protein 5A (NS5A) interacts with an NF-κB inhibitor immunomodulatory kinase, IKKε, and subsequently downregulates beta interferon (IFN-β) promoter activity. We further demonstrate that NS5A inhibits DDX3-mediated IKKε and interferon regulatory factor 3 (IRF3) phosphorylation. We also note that hyperphosphorylation of NS5A mediates protein interplay between NS5A and IKKε, thereby contributing to NS5A mediated modulation of IFN-β signaling. Lastly, NS5A inhibits IKKε-dependent p65 phosphorylation and NF-κB activation. Based on these findings, we propose NS5A as a novel regulator of IFN signaling events, specifically by inhibiting IKKε downstream signaling cascades through its interaction with IKKε. Taken together, these data suggest an additional mechanistic means by which HCV modulates host antiviral innate immune responses to promote persistent viral infection.

• Journal of Microbiology
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• v.44 no.1
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• pp.98-105
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• 2006

Yersinia enterocolitica induces a broad range of gastrointestinal syndromes, including acute enteritis. We previously reported that the clinical isolate, Y. enterocolitica KU14, which lacks pYV, was still capable of causing clinical infection. The present study demonstrated that KU14 did not trigger the death of macrophages in vitro, unlike WA-314 (ATCC51871, which harbors the pYV virulence plasmid). However, the intracellular growth of KU14 in the macrophages was greater than that of WA-C (ATCC51872, a non-plasmid harboring the derivative pYV plasmid). Treatment with a cholesterol-binding drug $(\beta-cyclodextrin)$ that affected lipid rafts resulted in a dramatic reduction in the inracellular growth of KU14. These data clearly indicate that the enhanced inracellular growth of KU14 is related to lipid raft-mediated infection.

• Molecules and Cells
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• v.37 no.4
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• pp.275-285
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• 2014

Macrophages, found in circulating blood as well as integrated into several tissues and organs throughout the body, represent an important first line of defense against disease and a necessary component of healthy tissue homeostasis. Additionally, macrophages that arise from the differentiation of monocytes recruited from the blood to inflamed tissues play a central role in regulating local inflammation. Studies of macrophage activation in the last decade or so have revealed that these cells adopt a staggering range of phenotypes that are finely tuned responses to a variety of different stimuli, and that the resulting subsets of activated macrophages play critical roles in both progression and resolution of disease. This review summarizes the current understanding of the contributions of differentially polarized macrophages to various infectious and inflammatory diseases and the ongoing effort to develop novel therapies that target this key aspect of macrophage biology.

• Journal of Industrial Convergence
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• v.19 no.3
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• pp.35-40
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• 2021

This study attempted to derive important factors of emerging infectious diseases by collecting and analyzing text data onto emerging infectious diseases. For this purpose, articles in the Naver News database were directly crawled, pre-processed, and used for data analysis. In addition, additional analysis was performed using Big Kinds. As a result of the priority analysis, the importance was shown in the order of corona, infectious disease, quarantine, vaccine, outbreak, virus, infection, and development. As a result of the proximity centrality analysis, the importance was shown in the order of government, death, and plan, and the analysis result of Big Kinds showed that Covid-19 and the Korea Centers for Disease Control and Prevention were important. Based on the results of this study, it can be said that the government's policy support is needed to raise public awareness of new infectious diseases, prevent disease, and develop vaccines and treatments.

• IMMUNE NETWORK
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• v.20 no.4
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• pp.28.1-28.25
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• 2020

The recent emergence of the novel coronavirus (CoV) or severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses a global threat to human health and economy. As of June 26, 2020, over 9.4 million cases of infection, including 482,730 deaths, had been confirmed across 216 countries. To combat a devastating virus pandemic, numerous studies on vaccine development are urgently being accelerated. In this review article, we take a brief look at the characteristics of SARS-CoV-2 in comparison to SARS and Middle East respiratory syndrome (MERS)-CoVs and discuss recent approaches to coronavirus disease-2019 (COVID-19) vaccine development.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.323-330
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• 2009

Nontuberculous mycobacteria (NTM) are a major cause of opportunistic infections in immunocompromised patients, making the reliable and rapid identification of NTM to the species level very important for the treatment of such patients. Therefore, this study evaluated the usefulness of the novel target genes tuf and tmRNA for the identification of NTM to the species level, using a PCRrestriction fragment length polymorphism analysis (PRA). A total of 44 reference strains and 17 clinical isolates of the genus Mycobacterium were used. The 741 bp or 744 bp tuf genes were amplified, restricted with two restriction enzymes (HaeIII/MboI), and sequenced. The tuf gene-PRA patterns were compared with those for the tmRNA (AvaII), hsp65 (HaeIII/HphI), rpoB (MspI/HaeIII), and 16S rRNA (HaeIII) genes. For the reference strains, the tuf gene-PRA yielded 43 HaeIII patterns, of which 35 (81.4%) showed unique patterns on the species level, whereas the tmRNA, hsp65, rpoB, and 16S rRNA-PRAs only showed 10 (23.3%), 32 (74.4%), 19 (44.2%), and 3 (7%) unique patterns after single digestion, respectively. The tuf gene-PRA produced a clear distinction between closely related NTM species, such as M. abscessus (557-84-58) and M. chelonae (477-84-80-58), and M. kansasii (141-136-80-63-58-54-51) and M. gastri (141-136-117-80-58-51). No difference was observed between the tuf-PRA patterns for the reference strains and clinical isolates. Thus, a diagnostic algorithm using a tuf gene-targeting PRA is a promising tool with more advantages than the previously used hsp65, rpoB, and 16S rRNA genes for the identification of NTM to the species level.

• Genomics & Informatics
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• v.16 no.4
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• pp.26.1-26.12
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• 2018

Shigella spp. constitutes some of the key pathogens responsible for the global burden of diarrhoeal disease. With over 164 million reported cases per annum, shigellosis accounts for 1.1 million deaths each year. Majority of these cases occur among the children of the developing nations and the emergence of multi-drug resistance Shigella strains in clinical isolates demands the development of better/new drugs against this pathogen. The genome of Shigella flexneri was extensively analyzed and found 4,362 proteins among which the functions of 674 proteins, termed as hypothetical proteins (HPs) had not been previously elucidated. Amino acid sequences of all these 674 HPs were studied and the functions of a total of 39 HPs have been assigned with high level of confidence. Here we have utilized a combination of the latest versions of databases to assign the precise function of HPs for which no experimental information is available. These HPs were found to belong to various classes of proteins such as enzymes, binding proteins, signal transducers, lipoprotein, transporters, virulence and other proteins. Evaluation of the performance of the various computational tools conducted using receiver operating characteristic curve analysis and a resoundingly high average accuracy of 93.6% were obtained. Our comprehensive analysis will help to gain greater understanding for the development of many novel potential therapeutic interventions to defeat Shigella infection.

• Journal of the Korean Data and Information Science Society
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• v.14 no.3
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• pp.615-622
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• 2003

The severe acute respiratory syndrome(SARS) is a novel infectious disease with global impact. The rapid worldwide spread of SARS has led to 30 countries reporting cases of July 13, 2003. In this paper, we develop a statistical model for SARS-caused-death data under some assumptions. The model developed is a continuous time Markov process with a constant intensity for each stage.

• Health Policy and Management
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• v.32 no.3
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• pp.330-333
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• 2022

Korea's quarantine response to the novel coronavirus (coronavirus disease 2019 [COVID-19]) pandemic is based on the sacrifice of health professionals, especially public health doctors (PHDs) who were called out first and put in the first place in the country. PHDs performed major quarantine tasks, such as collecting samples from screening clinics and epidemiological investigations, in various parts of the country, including the Daegu area, where the first large-scale COVID-19 confirmed cases in Korea and explosively increased. Because of their position as fixed-term civil servants, however, PHDs' professionalism as doctors was ignored, and they were not properly compensated for their work. They were also exposed to problems such as a high risk of infection, mental suffering, and various human rights violations. We must prepare concrete measures to improve the fundamental treatment of PHDs and protect their human rights in order to prepare for a possible infectious disease pandemic in the future.