• Korean Journal of Materials Research
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• v.22 no.3
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• pp.145-149
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• 2012

Red phosphors of $Gd_{1-x}Al_3(BO_3)_4:{Eu_x}^{3+}$ were synthesized by using the solid-state reaction method. The phase structure and morphology of the phosphors were measured using X-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM), respectively. The optical properties of $GdAl_3(BO_3)_4:Eu^{3+}$ phosphors with concentrations of $Eu^{3+}$ ions of 0, 0.05, 0.10, 0.15, and 0.20 mol were investigated at room temperature. The crystals were hexagonal with a rhombohedral lattice. The excitation spectra of all the phosphors, irrespective of the $Eu^{3+}$ concentrations, were composed of a broad band centered at 265 nm and a narrow band having peak at 274 nm. As for the emission spectra, the peak wavelength was 613 nm under a 274 nm ultraviolet excitation. The intensity ratio of the red emission transition ($^5D_0{\rightarrow}^7F_2$) to orange ($^5D_0{\rightarrow}^7F_1$) shows that the $Eu^{3+}$ ions occupy sites of no inversion symmetry in the host. In conclusion, the optimum doping concentration of $Eu^{3+}$ ions for preparing $GdAl_3(BO_3)_4:Eu^{3+}$ phosphors was found to be 0.15 mol.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.630-636
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• 2013

Recently, there has been a growing body of evidence showing that cellular microRNAs (miRNAs) are involved in virus-host interactions. Numerous studies have focused on analyses of the expression profiles of cellular miRNAs, but the expression patterns of Dicer, which is responsible for the generation of miRNAs, have only rarely been explored in Gallus gallus. We developed a duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay for the relative quantification of the mRNAs of Dicer and ${\beta}$-actin in G. gallus. To apply this method, the expression of Dicer in avian cells after infection with avian leukosis virus subgroup J (ALV-J) was detected using our established duplex real-time RT-PCR. The duplex real-time RT-PCR assay is sufficiently sensitive, specific, accurate, reproducible, and cost-effective for the detection of Dicer in G. gallus. Furthermore, this study, for the first time, demonstrated that ALV-J can induce differential expression of Dicer mRNA in the ALV-J-infected cells.

• Reproductive and Developmental Biology
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• v.34 no.1
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• pp.41-46
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• 2010

The objective of this study was to evaluated the efficiency of sperm cryosurvival using each extenders Triladyl and LEY containing egg yolk to the cryopreservation of separated sperm by percoll in miniature pig. The ejaculated semen from miniature pig was separated by 65% percoll and un-separated sperm as a control before freezing. The freezing of diluted semen added with Triladyl containing egg yolk and LEY solution (solution I: 11% Lactose or Triladyl + egg yolk; solution II: solution I + glycerol + OEP). Analysis of sperm ability was estimated by viability, capacitation acrosome reaction using chlortetracycline (CIC) the morphologic abnormality and hypoosmotic swelling test(HOST). The groups were designed that as separated sperm by Percoll with Triladyl(ST) or LEY(SL) for cryopreservation. And unseparated sperm with Triladyl(UT) or LEY(UL). As a results, the viability was higher significantly(p<0.05) in ST, SL, UT than UL extender. The morphologic abnormality was measured significantly (p<0.05) lower in ST than other extenders. The AR-patterned in CTC analysis was measured significantly(p<0.05) lower in SL and UL than other extenders. In conclusion, using Triladyl extender resulted in viability and morphology of separated sperm by percoll that were effective than using LEY extender, but it resulted in capacitation acrosome reaction was lower than using LEY extender.

• Clinical and Experimental Pediatrics
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• v.55 no.2
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• pp.42-47
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• 2012

$Mycoplasma$ $pneumoniae$ (MP), the smallest self-replicating biological system, is a common cause of upper and lower respiratory tract infections, leading to a wide range of pulmonary and extra-pulmonary manifestations. MP pneumonia has been reported in 10 to 40% of cases of community-acquired pneumonia and shows an even higher proportion during epidemics. MP infection is endemic in larger communities of the world with cyclic epidemics every 3 to 7 years. In Korea, 3 to 4-year cycles have been observed from the mid-1980s to present. Although a variety of serologic assays and polymerase chain reaction (PCR) techniques are available for the diagnosis of MP infections, early diagnosis of MP pneumonia is limited by the lack of immunoglobulin (Ig) M antibodies and variable PCR results in the early stages of the infection. Thus, short-term paired IgM serologic tests may be mandatory for an early and definitive diagnosis. MP infection is usually a mild and self-limiting disease without specific treatment, and if needed, macrolides are generally used as a first-choice drug for children. Recently, macrolide-resistant MP strains have been reported worldwide. However, there are few reports of apparent treatment failure, such as progression of pneumonia to acute respiratory distress syndrome despite macrolide treatment. The immunopathogenesis of MP pneumonia is believed to be a hyperimmune reaction of the host to the insults from MP infection, including cytokine overproduction and immune cell activation (T cells). In this context, immunomodulatory treatment (corticosteroids or/and intravenous Ig), in addition to antibiotic treatment, might be considered for patients with severe infection.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.209-214
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• 1984

Since 1980, burley tobacco plants grown mainly in the western hat of the Korea. have shown two new types of disease symptom. Both symptoms were found to be caused by two different PVY strains : the vein banding type by a PVY strain designated as PVY-VB and necrosis on leaf veins by a PVY strain designated as PVY-VN, Identification of the PVY strains was based on host range test. aphid( Myzus Persicae) transmission test, physical properties, serology, and observation of virus particle morphology. The virus particles were measured to be about 730 nm without any difference in shape or dimensions between the two strains. Both strains also gave a positive reaction to the PVY antiserum in SDS-agar gel double diffusion test. These strains, however, gave a negative reaction to the tobacco etch virus and tobacco vein mottling virus antisera.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.203-209
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• 2007

Infection structures were observed using a fluorescence microscope at the penetration sites on the leaves of potato plants pre-inoculated with the bacterial strains Pseudomonas putida TRL2-3, Micrococcus luteus TRK2-2, and Flexibacteraceae bacterium MRL412, which mediated an induced systemic resistance on potato plants against late blight disease caused by Phytophthora infestans. In order to compare the infection structures on the leaves expressing systemic acquired resistance, the leaves of potato plants pre-treated with DL-3-amino butyric acid (BABA) were also observed after challenge inoculation with the same pathogen. The infection structures were investigated. The total number of germination and appressorium formation of P. infestans were counted. Furthermore, the frequencies of fluorescent epidermal cells at the penetration sites, which indicate a defense response of plant cell, were estimated. There were no differences on the germination rates of the fungal cysts among the untreated control, BABA pre-treated, and bacterial strains pre-inoculated plants. However, appressorium formation was slightly decreased on the leaves of BABA pre-treated plants compared to those of untreated as well as bacterial strains pre-inoculated plants. Furthermore, the frequencies of fluorescent cells of BABA pre-treated and bacterial strains pre-inoculated were higher than that of untreated plants, indicating an active defense reaction of the host cells against the fungal attack. On the other hand, the pre-treatment with BABA caused a stronger fluorescent of epidermal cells at the penetration sites compared to the pre-inoculation with the bacterial strains. Interestingly, the frequency of fluorescent cells by BABA, however, was lower than that by the bacterial strains. Based on the results it is suggested that the infection structures showing resistance reaction on the leaves of potato plants were different between by pre-inoculation with bacterial strains and by pre-treatment with BABA against the late blight pathogen.

• Biomedical Science Letters
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• v.7 no.4
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• pp.161-166
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• 2001

Most mammalian cells take up glucose by passive transport proteins in the plasma membranes. The best known of these proteins is the human erythrocyte glucose transporter, GLUT1. High levels of heterologous expression far the transporter are necessary for the investigation of its three-dimensional structure by crystallization. To achieve this, the baculovirus expression system has become popular choice. However, Spodoptera frugiperda Clone 9 (Sf9) cells, which are commonly employed as the host permissive cell line to support baculovirus replication and protein synthesis, grow well on TC-100 medium that contains 0.1% D-glucose as the major carbon source, suggesting the presence of endogenous glucose transporters. Furthermore, very little is known of the endogenous transporters properties of Sf9 cells. Therefore, human GLUT1 antibodies would play an important role for characterization of the GLUT1 expressed in insect cell. However, the successful use of such antibodies for characterization of GLUT1 expression m insect cells relies upon their specificity for the human protein and lack of cross-reaction with endogenous transporters. It is therefore important to determine the potential cross-reactivity of the antibodies with the endogenous insect cell glucose transporters. In the present study, the potential cross-reactivity of the human GLUT1 antibodies with the endogenous insect cell glucose transporters was examined by Western blotting. Neither the antibodies against intact GLUT1 nor those against the C-terminus labelled any band migrating in the region expected fur a protein of M$_r$ comparable to GLUT1, whereas these antibodies specifically recognized the human GLUT1. Specificity of the human GLUT1 antibodies tested was also shown by cross-reaction with the GLUT1 expressed in insect cells. In addition, the insect cell glucose transporter was found to have very low affinity for cytochalasin B, a potent inhibitor of human erythrocyte glucose transporter.

• Research in Plant Disease
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• v.13 no.1
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• pp.24-29
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• 2007

A total of 35 strains of Ralstonia solanacearum isolated from wilted pepper and tomato plants in Korea were analyzed for their genetic diversity by bacteriological, pathological and molecular biological approaches. All the strains were identified as R. solanacearum biovar 4 on the basis of physiological and biochemical tests, and species-specific PCR primers. Pathogenicity of the strains was confirmed by inoculating on 4-week-old pepper and tomato seedlings. Using cluster analysis based on repetitive sequence-based polymerase chain reaction (rep-PCR) genomic fingerprints, R. solanacearum strains isolated from pepper and tomato in Korea divided into 6 groups showing a high degree of genetic diversity at 55% similarity level. The genetic diversify of strains was not significantly correlated with their geographic origins and host plants.

• Journal of agricultural medicine and community health
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• v.6 no.1
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• pp.5-12
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• 1981

Paragonimus infection is prevalent in Korea, establishing several endemic foci. Kim(1969) reported an endemic area in Hyeonbuk Myeon. Yangyang-Gun, but thereafter no further epidemiologic study of Paragonimus infection was performed in the Gangweon-Do. Hoengseong-Gun is mountainous area which is located in the southwestern part of Gangweon-Do and borders with Hongcheon-Gun on the east, with Pyeongchang-Gun on the east, with Yeongweol-Gun and Weonseong-Gun on the south, and with Yangpyeong-Gun on west. The author carried out an epidemiologic study of Paragonimus infection by intradermal test with V.B.S antigen, and of intermediate host (crayfish) in Hoengseong-Gun, Gangweon-Do. The results are summarized as follows: 1. The positive skin test reaction to Paragonimus antigen was 14.5% from 2,807 examiness; 16.0% in male and 11.6% in female and no sex or age difference on the skin test positive reactions was noticed among the villages. 2. The positive skin test reactions were 31.3% in Gapcheon-Myeon, 20.5% in Cheongil-Myeon and 19.8% in Woocheon-Myeon. Primary school children in Byeongjibang-ri, Gapcheon-Myeon showed positive in 36.4%. 3. The prevalence by skin test reaction by social strata was 16.1% (226 out of 1,408) in primary school children, 12.8% out of 725) in middle school, 6.4% (11 out of 172) in high school students, and 15.3% (77 out of 502) in inhabitants of Heongseong-Gun. 4. Metacercarial positives of Paragonimus in crayfish were 20.9%. Through the survey results, it is postulated that Heongseong-Gun, Gangweon-Do is to be categorized as an endemic area of Paragonimus infection.

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.82-86
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• 2015

$Dy^{3+}$- and $Eu^{3+}$-codoped $CaMoO_4$ Phosphors were synthesized by using the solid-state reaction method. The crystal structure, morphology, and optical properties of the resulting phosphor particles were investigated by using the X-ray diffraction, field-emission scanning electron microscopy, and photoluminescence spectroscopy. XRD patterns exhibited that all the synthesized phosphors showed a tetragonal system with a main (112) diffraction peak, irrespective of the content of $Eu^{3+}$ ions. As the content of $Eu^{3+}$ ions increased, the grains showed a tendency to agglomerate. The excitation spectra of the synthesized powders were composed of one strong broad band centered at 305 nm in the range of 220 - 350 nm and several weak peaks in the range of 350 - 500 nm resulting from the 4f transitions of activator ions. Upon ultraviolet excitation at 305 nm, the yellow emission line due to the $^4F_{9/2}{\rightarrow}^6H_{13/2}$ transition of $Dy^{3+}$ ions and the main red emission spectrum resulting from the $^5D_0{\rightarrow}^7F_2$ transition of $Eu^{3+}$ ions were observed. With the increase of the content of $Eu^{3+}$, the intensity of the yellow emission band gradually decreased while that of the red emission increased. These results indicated that the emission intensities of yellow and red emissions could be modulated by changing the content of the $Dy^{3+}$ and $Eu^{3+}$ ions incorporated into the host crystal.