• Journal of Life Science
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• v.12 no.2
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• pp.61-74
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• 2002

One of the major aims in studying plant viruses is to minimise the development of symptoms in infected plants. With the advent of in vitro transcript mediated research on plant viruses, substantial progress has been made. This article describes the biology of a plant specific RNA virus, Johnsongrass mosaic virus (JGMV), important to Australian sorghum and corn agriculture and, in particular, at a molecular level which of the RNA sequences in its genome that make it possible for the virus to move from cell to cell, and eventually spread systemically throughout the entire plant. The JGMV has caused considerable yield losses in maize and sorghum over a number of years in Australia. Incidents where 100% of the crop has been infected are on record. The use of this virus is convenient under laboratory conditions because it can be readily transmitted by mechanical inoculation with infected leaf sap, which obviates the need for maintaining aphid colonies. The JGMV is a single stranded positive sense RNA virus.

• BMB Reports
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• v.56 no.6
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• pp.335-340
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• 2023

During normal physiological and abnormal pathophysiological conditions, all cells release membrane vesicles, termed extracellular vesicles (EVs). Growing evidence has revealed that EVs act as important messengers in intercellular communication. EVs play emerging roles in cellular responses and the modulation of immune responses during virus infection. EVs contribute to triggering antiviral responses to restrict virus infection and replication. Conversely, the role of EVs in the facilitation of virus spread and pathogenesis has been widely documented. Depending on the cell of origin, EVs carry effector functions from one cell to the other by horizontal transfer of their bioactive cargoes, including DNA, RNA, proteins, lipids, and metabolites. The diverse constituents of EVs can reflect the altered states of cells or tissues during virus infection, thereby offering a diagnostic readout. The exchanges of cellular and/or viral components by EVs can inform the therapeutic potential of EVs for infectious diseases. This review discusses recent advances of EVs to explore the complex roles of EVs during virus infection and their therapeutic potential, focusing on HIV-1.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.70-74
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• 2015

The current market size of insect industry in Korea is estimated at 300 million dollars and more than 500 local farms are related to many insect industry. One of the strong candidates for insect industry is Korean horn beetle, Allomyrina dichotoma. Early this year, we reported a viral disease extremely fatal to A. dichotoma larvae. While we were proceeding a nationwide investigation of this disease, it was informed that similar disease symptom has been occurred occasionally during past over 10 years. The symptom can be easily confused with early stage of bacterial infection or physiological damage such as low temperature and high humidity. A peroral infection with the purified virus to healthy larvae produced a result that only 21% of larvae survived and became pupae. Although some of the survived adult beetle was deformational, many of them had no abnormal appearance and even succeeded in mating. Later, these beetles were examined if they were carrying the virus, and all except one were confirmed as live virus carrier. This implies that these beetles may fly out and spread the disease to the nature. We found the evidence for this possibility by collecting a few wild A. dichotoma larvae which were virus infected, near two local farms rearing A. dichotoma larvae. So far, transovarial transmission of this virus to the eggs, or horizontal transmission to other commercially reared insects is not known yet.

• Korean Journal of Veterinary Research
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• v.61 no.2
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• pp.12.1-12.9
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• 2021

The mosquito-borne pathogen Zika virus may result in neurological disorders such as Guillain-Barré syndrome and microcephaly. The virus is classified as a member of the Flaviviridae family and its wide spread in multiple continents is a significant threat to public health. So, there is a need to develop animal models to examine the pathogenesis of the disease and to develop vaccines. To examine the clinical profile during Zika virus infection, we infected neonatal and adult wild-type mice (C57BL/6 and Balb/c) and compared the clinical signs of African-lineage strain (MR766) and Asian-lineage strain (PRVABC59, MEX2-81) of Zika virus. Consistent with previous reports, eight-week-old female Balb/c mice infected with these viral strains showed no changes in body weight, survival rate, and neurologic signs, but demonstrated increases in the weights of spleens and hearts. However, one-day-old neonates showed significantly lower survival rate and body weight with the African-lineage strain than the Asian-lineage strain. These results confirmed the pathogenic differences between Zika virus strains. We also evaluated the clinical responses in neonatal and adult mice of different strains. Our findings suggest that these are useful mouse models for characterization of Zika virus for vaccine development.

• Microbiology and Biotechnology Letters
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• v.52 no.3
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• pp.221-232
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• 2024

Zoonotic diseases are rare but the transmission of disease to humans may cause serious illness. Nipah virus (NiV) is a bat-borne zoonotic pathogen, which can cause severe encephalitis and respiratory distress. The transmission of Nipah virus from bats to humans was first reported in Malaysia in 1998. Different strains of NiV show different epidemiological and clinical features. Few of the strains are highly lethal and can spread to the community resulting in a global threat. However, the availability of effective management or prophylactic measures are only limited. Thus, it is essential to contain such outbreaks by implementing proper infection control and surveillance measures. Many serological and molecular diagnostic techniques have been developed for diagnosis of this infection. This review mainly focuses on the epidemiology, transmission of Nipah virus, pathogenesis and management of NiV infection. The review also throws light on the immune response of NiV in humans and the role of One Health approach in prevention and control of NiV infection.

• Korean Journal of Microbiology
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• v.9 no.2
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• pp.69-73
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• 1971

On June in 1970 the authors discovered a pathogenecity, cytoplasmic polyhedrosis virus, of the Smithia virus in the larvae of Liparis dispay L. appeared on quercus forest in Chung-Neung district and had carried out a experiment to detect the pathogenecity of Smithia virus through the inoculation of it into the larvase, such as Liparis dispay L. Hyphantrea cunea DRURY, and Dendrolinus spectabilis BUTLER. The results obtained were as follows ; 1) Death rate of L.dispay and D.spectabilis treated by 10$^{6}$ /ml cytoplasmic polyhedrosis virus of Smithis virus were 88.0% and 85.5% respectively, when the larvaes of these insects are big enough. But there were none of pathogenecity in case of Hyphantrea cunea DRURY. 20 Dead larvae caused by the injection of Smithia virus had begum to find out about on 10 days after inoculation. Miximum death rate of L. didpay and D. spectabilis appeared on 20-25days nad on 25-30days, respectively, after the incoulation. 3) In the cytoplasm of Mid-gut cylindrical cells of both of these insects, polyhedrosis, such s hexagonal (0.5-2.0-6.0 micron) were found out and in these insects, polyhedrosis, such as hexaginal (0.5-2.0-6.0 mivton) were found out and in case of D.spectabilis were a few polyhedrosis, such as tetragonal, trianglar polyhedrosis. 4) Diluted concentration of `0$^{6}$ /ml cytoplasmic polyhedrosis virus of Smithia virus were spread out in the field conditions. The corrected mortality was confirmed as about 87.8%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.596-616
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• 2021

A global increase in fish consumption has led to a rapid expansion of aquaculture production, which has been linked to enhancing the spread of infectious diseases. Viral diseases can cause high mortality in many cultured fish species, posing a serious threat to the aquaculture industry. Infectious hematopoietic necrosis virus (IHNV) is one of the primary threats to aquacultured salmonid species, causing huge economic losses. Since the first report in cultured sockeye salmon Oncorhynchus nerka during the 1950s in North America, IHNV has spread to other regions, including Europe, Asia, South America, and Africa by transportation of infected fish and eggs, causing disease and increasing mortality in a wide variety of salmonid species. Here, we review existing information relevant to IHNV: its phylogenetic characteristics, origin, infection history, virulence determinants, susceptible hosts, vectors, and vaccine development. This review also addresses a possible cross-species transmission of IHNV to a new host, olive flounder Paralichthys olivaceus, a cultured fish of economic importance in East Asian countries.

• Korean Journal of Veterinary Research
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• v.64 no.2
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• pp.13.1-13.6
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• 2024

Avian influenza A viruses (IAVs) present significant threats to both animal and human health through their potential for cross-species transmission and global spread. Clade 2.3.4.4 H5Nx highly pathogenic avian IAVs initially emerged in East Asia between 2013 and 2014. Since then, they have spread to Europe, Africa, and America via migratory bird flyways. However, beyond viral transmission primarily facilitated by migratory birds, the potential involvement of other intermediate factors for virus transmission remains poorly investigated. This study aimed to investigate the role of wild rodents as intermediary hosts in the ecology of avian IAVs in Gyeonggi province, South Korea. By capturing and analyzing 189 wild rodents near poultry farms and migratory bird habitats in 2013 and 2014 and employing serological assays and virus isolation techniques, we found no evidence of IAV infection among these populations. Our results suggest that wild rodents may not significantly contribute to the transmission dynamics of IAVs within these regions.

• Journal of applied mathematics & informatics
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• v.41 no.5
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• pp.1017-1035
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• 2023

In this paper, we construct a monkeypox model which is similar to smallpox infection. It is caused by a monkeypox virus which is related to Poxviridae family. It will occur mostly in West African communities and in remote Central. We develop a system of differential equations for an SEIR (Suspected, Exposed, Infected and Recovered) model and analyze the outbreak of monkeypox disease and its effect on United States(US) population. We establish theorems on asymptotical stability conditions for endemic equilibrium and disease-free equilibrium. The basic reproduction number R₀ has been determined using next generation matrix. We expect that this study will be effective at controlling monkeypox spread in United States. Our goal is to see whether monkeypox can be controlled and destroyed by smallpox vaccination. We find that monkeypox is controllable and can be fully destroyed in disease free state by vaccination. However, in the endemic state, monkeypox cannot be destroyed by vaccination alone.

• Korean Journal of Artificial Intelligence
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• v.8 no.1
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• pp.7-9
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• 2020

In this paper, a study was conducted to find a self-diagnosis method to prevent the spread of COVID-19 based on machine learning. COVID-19 is an infectious disease caused by a newly discovered coronavirus. According to WHO(World Health Organization)'s situation report published on May 18th, 2020, COVID-19 has already affected 4,600,000 cases and 310,000 deaths globally and still increasing. The most severe problem of COVID-19 virus is that it spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes, which occurs in everyday life. And also, at this time, there are no specific vaccines or treatments for COVID-19. Because of the secure diffusion method and the absence of a vaccine, it is essential to self-diagnose or do a self-diagnosis questionnaire whenever possible. But self-diagnosing has too many questions, and ambiguous standards also take time. Therefore, in this study, using SVM(Support Vector Machine), Decision Tree and correlation analysis found two vital factors to predict the infection of the COVID-19 virus with an accuracy of 80%. Applying the result proposed in this paper, people can self-diagnose quickly to prevent COVID-19 and further prevent the spread of COVID-19.