• BMB Reports
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• v.33 no.4
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• pp.294-299
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• 2000

Proteolytic processing of the dengue virus serotype 2 polyprotein precursor is catalyzed by a host signal peptidase and a virus encoded two-component protease consisting of the nonstructural proteins, NS2B and NS3. We expressed in Escherichia coli the NS2B, NS3(pro) and NS2B-NS3 proteins from the dengue virus type 2 strain 16681 as N-terminal fusions with a hexahistidine affinity tag under the control of the inducible trc promoter. All fusion proteins were purified to >90% purity by detergent extraction of inclusion bodies and a single step metal chelate chromatography. Proteins were refolded on-column and recovered with yields of 0.5, 6.0 and 1.0 mg/l of E. coli culture that was grown to $OD_{600}=1.0$ for NS2B, NS3(pro) and NS2B-NS3, respectively. Purified proteins gave strong signals in Western blots using $Ni^{2+}-nitrilotriacetic$ acid as a probe for the presence of the polyHis tag. During the purification process, $(His)_{6}NS2B-NS3$ was apparently not autoproteolytically cleaved at the NS2B/NS3 site.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.632-643
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• 2019

In recent years, large scale damages from arbovirus infections by mosquitoes have been reported worldwide due to factors such as change in global climate, increased overseas travel, and increased logistics movement between countries. Among them, Zika virus and dengue virus belonging to genus Flavivirus are representative. In this study, we performed in-depth analyses of the envelope (E) protein that perform essential functions for host infection of Zika virus and dengue virus based on bioinformatics databases. The domain analysis of E protein was performed to determine the type, location, and function, and homology analysis for each domain. From these results, EDIII showing low homology was identified. The homology and immunogenicity of each peptide constituting EDIII were analyzed and three-dimensional structures were modeled. Furthermore, we discussed their biological meaning and how they could be used.

• BMB Reports
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• v.35 no.2
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• pp.206-212
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• 2002

The NS2B-NS3(pro) polyprotein segment from the dengue virus serotype 2 strain 16681 was purified from overexpressing E. coli by metal chelate affinity chromatography and gel filtration. Enzymatic activity of the refolded NS2B-NS3(pro) protease complex was determined in vitro with dansyl-labeled peptide substrates, based upon native dengue virus type 2 cleavage sites. The 12mer substrate peptides and the cleavage products could be separated by reversed-phase HPLC, and were identified by UV and fluorescence detection. All of the peptide substrates (representing the DEN polyprotein junction sequences at the NS2A/NS2B, NS2B/NS3, NS3/NS4A and NS4B/NS5 sites) were cleaved by the recombinant protease NS2B-NS3(pro). No cleavage was observed with an enzymatically inactive S135A mutant of the NS3 protein, or with a modified substrate peptide of the NS3/NS4A polyprotein site that contained a K2093A substitution. Enzymatic activity was dependent on the salt concentration. A 50% decrease of activity was observed in the presence of 0.1M sodium chloride. Our results show that the NS3 protease activity of the refolded NS2B-NS3(pro) protein can be assayed in vitro with high specificity by using cleavage-junction derived peptide substrates.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.99-99
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• 2003

• IMMUNE NETWORK
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• v.16 no.5
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• pp.261-270
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• 2016

The human immune system has evolved to fight against foreign pathogens. It plays a central role in the body's defense mechanism. However, the immune memory geared to fight off a previously recognized pathogen, tends to remember an original form of the pathogen when a variant form subsequently invades. This has been termed 'original antigenic sin'. This adverse immunological effect can alter vaccine effectiveness and sometimes cause enhanced pathogenicity or additional inflammatory responses, according to the type of pathogen and the circumstances of infection. Here we aim to give a simplified conceptual understanding of virus infection and original antigenic sin by comparing and contrasting the two examples of recurring infections such as influenza and dengue viruses in humans.

• Proceedings of the Korea Contents Association Conference
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• 2014.06a
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• pp.95-96
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• 2014

• Pediatric Infection and Vaccine
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• v.27 no.2
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• pp.140-146
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• 2020

Dengue fever (DF) is endemic throughout tropical and subtropical regions; however, it is not endemic in Korea. Imported infectious diseases should be suspected when encountering returned travelers with non-specific symptoms such as fever, rash, and headache. Persistent vomiting, abdominal pain, hemorrhagic tendency, hepatic enzyme abnormalities, and proteinuria are risk factors for the development of severe DF in a patient with DF. Severe hyperglycemia is also known to be related to poor prognosis in acute illness, and with certain underlying diseases that present with hyperglycemia, such as diabetes, it is related to the progression of severe DF. We report a DF case with severe hyperglycemia in an adolescent returning from India. Pediatric DF cases reported in Korea were also reviewed.

• Iberoamérica
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• v.21 no.2
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• pp.1-23
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• 2019

This study analyzes how the health program is implemented by political and economic factors in the case of Minga Ambiental program in Paraguay. In the field of critical medical anthropology, the practice of health care programs explains that socio-cultural and political and economic factors can be the main variables besides the primary purpose of preventing and eradicating the disease. In the same vein, this study also analyzed how community-based health programs operate by various external factors. As a result, the Minga Ambiental program is a health program called Dengue Fever, which has been tended to be sustained and expanded by various actors, including politicians and corporations in countries and communities, despite concerns about effectiveness. In this case, this study found that health programs can be operated by political and economic relations different from their original purpose, and are intertwined in various social contexts by various actors in constructing health programs.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.599-599
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• 2005

• Journal of Plant Biotechnology
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• v.41 no.1
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• pp.50-55
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• 2014

Plant-based vaccines possess some advantages over other types of vaccine biotechnology such as safety, low cost of mass vaccination programs, and wider use of vaccines for medicine. This study was undertaken to develop the transgenic maize as edible vaccine candidates for humans. The immature embryos of HiII genotype were inoculated with A. tumefaciens strain C58C1 containing the binary vectors (V662 or V663). The vectors carrying nptII gene as selection marker and scEDIII (V662) or wCTB-scEDIII (V663) target gene, which code EIII proteins inhibite viral adsorption by cells. In total, 721 maize immature embryos were transformed and twenty-two putative transgenic plants were regenerated after 12 weeks selection regime. Of them, two- and six-plants were proved to be integrated with scEDIII and wCTB-scEDIII genes, respectively, by Southern blot analysis. However, only one plant (V662-29-3864) can express the gene of interest confirmed by Northern blot analysis. These results demonstrated that this plant could be used as a candidated source of the vaccine production.