• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.166-191
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• 2012

This paper investigates how the agent specificity of economic infrastructure-related public company proceeds in overseas investments. At first this paper examines general features focused on investment region, project type, starting year, and then analyzes overseas investments based on specific cases with three classifications which are composed of special consulting type that do not accompany capital investment, FDI type, and type of overseas energy resources development that go with capital investment and business risk. Finally nationality issues that is generated by agent characteristics of infrastructure public company are interpreted in perspective of duality which is financial pressure and dependency of host county's position, and relationship with private capital of home country.

• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.357-363
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• 2013

The identification of bacteriophage proteins on the surface of Lactobacillus rhamnosus Pen was performed by LC-MS/MS analysis. Among the identified proteins, we found a phage-derived major tail protein, two major head proteins, a portal protein, and a host specificity protein. Electron microscopy of a cell surface extract revealed the presence of phage particles in the analyzed samples. The partial sequence of genes encoding the major tail protein for all tested L. rhamnosus strains was determined with specific primers designed in this study. Next, RT-PCR analysis allowed detection of the expression of the major tail protein gene in L. rhamnosus strain Pen at all stages of bacterial growth. The transcription of genes encoding the major tail protein was also proved for other L. rhamnosus strains used in this study. The present work demonstrates the spontanous release of prophage-encoded particles by a commercial probiotic L. rhamnosus strain, which did not significantly affect the bacterial growth of the analyzed strain.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.6-10
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• 2005

Immunoglobulin Y (IgY) obtained from chicken as the immunization host brings several advantages to antibody production, such as improved yield, lower cost, longer stability and higher specificity than mammalian immunoglobulin. In the present study, we attempted to produce IgY against a sialic acid-binding lectin, Maackia fauriei agglutinin (MFA), from egg yolk of white Leghorn hens. For the isolation of IgY from egg yolk, we applied a water dilution method. The weekly yield of IgY was determined by enzyme-linked immunosorbent assay, with a final yield of anti-MFA IgY from total IgY of approximately $1\%$. The yielded IgY were used to prepare IgY-affinity column conjugated with CNBr-activated Sepharose 4B, which resulted in the lectin being successfully purified in a single step from Maackia fauriei. This purified lectin exhibited the same hemagglutination activity as lectin purified using conventional purification methods.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1485-1490
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• 2006

In this study, comparative replicational properties of Hyphantria cunea nucleopolyhedrovirus (HycuNPV) in Lymantria dispar (IPLB-LdElta) and Spodoptera frugiperda (IPLB-Sf21) cell lines were investigated. Our microscopic observations showed that cytopathic effects (CPEs) in LdElta cells appeared 12 h later than those in Sf21 cells. Whereas polyhedral inclusion bodies (PIBs) formed at 48 h postinfection (p.i.) in LdElta cells, it formed at 36 h p.i. in Sf21 cells. Extracellular virus production determined according to the 50% tissue culture infective dose ($TCID_{50}$) method in LdElta cells started about 12 h later when compared with Sf21 cells. Titers of extracellular virus in LdElta and Sf21 cells were calculated as $1.77{\times}10^9$ plaque forming units (PFU)/ml and $5.6{\times}10^9PFU/ml$, respectively, at 72 h p.i. We also showed that viral DNA replication began at 12 h p.i. in both cell lines. Viral protein synthesis was determined by SDS-polyacrylamide gel electrophoresis (PAGE) and polyhedrin synthesis was observed at 12 h p.i. in both cell lines. The results indicate that while the synthesis of macromolecules is 12 h later and production of extracellular virus is almost 3-fold lower in LdElta cells compared with those in Sf21 cells, the LdElta cell line is still a productive cell line for infection of HycuNPV.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1350-1358
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• 2012

Viral pathogens, alongside other pathogens, have major effects on crustacean aquaculture. Hepatopancreatic parvovirus (HPV) is an emerging virus in the shrimp industry and has been detected in shrimp farms worldwide. The HPV genome has greater diversity than other shrimp viruses owing to its wide host range and geographical distribution. Therefore, developing diagnostic tools is essential to detect even small copy numbers from the target region of native HPV isolates. We have developed two easy to use quantitative real-time PCR kits, called Green Star and Dual Star, which contain all of the necessary components for real-time PCR, including HPV primers, using the primers obtained from the sequences of HPV isolates from Korea, and analyzed their specificity, efficiency, and reproducibility. These two kits could detect from 1 to $1{\times}10^9$ copies of cloned HPV DNA. The minimum detection limits obtained from HPV-infected shrimp were $7.74{\times}10^1$ and $9.06{\times}10^1$ copies in the Green Star and Dual Star assay kits, respectively. These kits can be used for rapid, sensitive, and efficient screening for HPV isolates from Korea before the introduction of postlarval stages into culture ponds, thereby decreasing the incidence of early development of the disease.

• Mycobiology
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• v.45 no.4
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• pp.263-269
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• 2017

The genus Peronospora, an obligate biotrophic group belonging to Oomycota, causes serious damage to a variety of wild and ornamental plants, as well as cultivated crops, such as beet, rose, spinach, and tobacco. To investigate the diversity of Peronospora species parasitic to Stellaria and Pseudostellaria (Caryophyllaceae) plants in Korea, we performed a morphological analysis on dried herbarium specimens and molecular phylogenetic inferences based on internal transcribed spacer rDNA and cox2 mitochondrial DNA sequences. As a result, it was confirmed that there are four species of Peronospora parasitic to specific species of Stellaria and Pseudostellaria, all of which were hitherto unrecorded in Korea: P. alsinearum (ex Stellaria media), P. stellariae-aquaticae (ex Stellaria aquatica), P. stellariae-uliginosae (ex Stellaria alsine), and P. pseudostellariae (ex Pseudostellaria palibiniana). In addition, Peronospora specimens parasitic to Pseudostellaria davidii differed morphologically from P. pseudostellariae owing to the large and ellipsoidal conidia; this morphological discrepancy was also validated by the high genetic divergence between the two species. Peronospora casparyi sp. nov. is described and illustrated here.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.5
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• pp.539-546
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• 2019

The major cultured marine fishes in sea off the coast Gyeongsangnam-do Province, South Korea, were assessed and included 9.3% rockfish Sebastes schlegelii, 7.8% red seabream Pagrus major, and 2.1% rock bream Oplegnathus fasciatus. The number of insurance payments related to disease mortality in cultured fish in 2017 was fourfold that in 2016. Economic loss in aquaculture due to disease in cultured fish is high and represents an important inhibitory factor affecting marine fishery productivity. In 2018, diseases led to severe production losses in several aquaculture species: 40.0% in rockfish, 11.4% in olive flounder Paralichthys olivaceus, 10.0% in filefish Thamnaconus modestus, and 9.3% in red seabream. Fish-parasitic pathogens such as Microcotyle sebastis, Alella spp., and Dactylogyrus spp. enter mainly via the gills and skin surface. Among bacterial pathogens, Vibrio species were most common, with Vibrio harveyi being the dominant species causing infections in these fishes. The bacterium Lactococcus garvieae is thought to exhibit host specificity in fish. The fish species in the present study exhibited a higher tendency for infection by heterologous pathogens than by a single pathogen; therefore, it is necessary to devise new strategies for treating diseases in cultured fish.

• Molecules and Cells
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• v.44 no.2
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• pp.63-67
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• 2021

The bed nucleus of the stria terminalis (BNST)-a key part of the extended amygdala-has been implicated in the regulation of diverse behavioral states, ranging from anxiety and reward processing to feeding behavior. Among the host of distinct types of neurons within the BNST, recent investigations employing cell type- and projection-specific circuit dissection techniques (such as optogenetics, chemogenetics, deep-brain calcium imaging, and the genetic and viral methods for targeting specific types of cells) have highlighted the key roles of glutamatergic and GABAergic neurons and their axonal projections. As anticipated from their primary roles in excitatory and inhibitory neurotransmission, these studies established that the glutamatergic and GABAergic subpopulations of the BNST oppositely regulate diverse behavioral states. At the same time, these studies have also revealed unexpected functional specificity and heterogeneity within each subpopulation. In this Minireview, we introduce the body of studies that investigated the function of glutamatergic and GABAergic BNST neurons and their circuits. We also discuss unresolved questions and future directions for a more complete understanding of the cellular diversity and functional heterogeneity within the BNST.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1090-1097
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• 2015

Traditionally, mistletoe is known as an effective anti-cancer medicinal plant, and lectin is recognized as a major component with cytotoxic and immuno-stimulant activity in mistletoe. A Korean mistletoe lectin (KML) has specificity to galactose and galactosamine and is distinguish from European mistletoe lectin (EML). When we examined the concentration of lectin in mistletoe originated from five different types of host trees, the result indicate that the lectin concentration is variable depending on the host tree. Noticeably, mistletoe from chestnut tree contains ten folds higher lectins than that of an oak tree. We also tested the concentration of KML and crude extract (KM-110) of Korean mistletoe that shows 90% cytotoxicity in L5178Y-ML25 lymphoma cell. In addition, the cells show 90% and 70% viability by the treatment of two neutralizing antibodies of KML, 9H7-D10 and 8B11-2C5 neutralization effect with two monoclonal antibodies of KML, 9H7-D10 and 8B11-2C5. Therefore, the result expected that the mistletoe contain some other cytotoxic components except lectin. Finally, the production of $TNF-{\alpha}$ and IL-6 by RAW 264.7 cells stimulated with lectin free-crude extract (LFKM-110) following neutralization by 9H7-D10 monoclonal antibody shows higher than that of lectin containing-crude extract (KM-110). These results suggest that the Korean mistletoe lectin ha a great potential to be developed as therapeutic agent of cancer.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.437-445
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• 2017

An analysis of recent studies and a field survey were conducted to investigate the distribution of the exotic species Ophraella communa LeSage (Coleoptera, Chrysomelidae) and the results' applicability for biological control against ragweed, which disturbs the island's ecosystem. The ragweed beetle (O. communa) can be found anywhere on the host plant Ambrosia artemisiifolia L., which grows in Jeju Island. Moreover, ragweed beetles possess the following characteristics: a high host plant specificity, a high-temperature resistance, an excellent mobility, and multivoltinism. Ragweed is extensively distributed and gradually expands its habitat further on Jeju Island. For this reason, it is recommended to take advantage of O. communa for the biological control of ragweed instead of pesticides or direct removal, considering that Jeju is endowed with many natural reserves and unique insular traits.