• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.25-29
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• 2012

Marine actinomycetes isolated from seaweed were screened for growth activation effects on the biodiesel-producing microalgae Dunaliella salina. Of the 98 actinomycetes studied, strain 288-11 isolated from the rhizosphere of Undaria pinnatifida showed potent growth activation. The strain was identified as Streptomyces anulatus based on 16S rDNA sequence analysis. The cell density increased up to 2.1-fold with the addition of 1 mg/mL of extract to the medium. To understand the effect of adding S. anulatus extract, the gross biochemical composition and fatty acids of D. salina were determined.

• Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.227-235
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• 2009

The marine toxic dinoflagellate Alexandrium catenella has been implicated in numerous paralytic shellfish poisoning (PSP) events in many countries. Due to difficulties in rapidly identifying A. catenella, field-based study of this species has been problematic. The present study developed a TaqMan format A. catenella-specific probe for real-time PCR assay (specific to Korean genotype) based on LSU rDNA sequence information for studying geographic and temporal distribution of the species in surface sediments and water columns of Jinhae Bay, Korea. The field survey from 2007 to 2008 revealed that A. catenella occurred in most seasons at low densities, mostly below 1 cell $mL^{-1}$, and was more abundant in spring (maximum cell density of 2 cells $mL^{-1}$) when shellfish exceed the quarantine toxin level for PSP toxins in Jinhae Bay.

• Asian Journal of Turfgrass Science
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• v.13 no.3
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• pp.153-158
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• 1999

'Konwoo', bermudagrass[Cynodon dactylon (L) Pers.] (Patent registration no. 2000-724), a vegetative cultivar, was developed by the Dept. of Horticultural Science, Konkuk University, Seoul. 'Konwoo' was selected in 1997 among 20 lines collected from Korea, Japan, Tiwan, China, U. S. A, and Australia. 'Konwoo' morphologically similar to Tifway 419 was selected due to the erect type, short leaf length($1.3\pm$0.3cm), fine leaf($2.0\pm$0.5mm), rapid establishment and recoverage, many stolon number and high shoot density. When 'Konwoo' was compared to the four other bermudagrass lines at the DNA level using 54 PCR primers, it had the specific bands with primer No. 102, 275, 280, 295, 300, 739 by RAPD analysis.

• Asian Journal of Turfgrass Science
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• v.13 no.3
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• pp.147-151
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• 1999

"Konhee" zoysiagrass[Zoysia matrella (L) Merr.](Patent registration no. 2000-723), a vegetative cultivar, was developed by the Dept. of Horticultural Science, Konkuk University, Seoul. "Konhee" was selected from the cross, ZKV6$\times$ZKV10, in 1997 and F1 seed were produced in the greenhouse in 1996. "Konhee" is superior to the other fine leaf zoysiagrass lines in many traits such as erect type, plant height($8.5\pm$2.0cm), short 3rd stolon length($3.4\pm$0.5cm), dark green, fine leaf($2.3\pm$0.2mm), low first sheath height($0.9\pm$0.2cm), rapid establishment and recoverage, many stolon number, and high shoot density. When "Konhee" was compared to the five other zoysisagrass lines at the DNA level using 35 PCR primers, it had the specific bands with primer No. 740, 544, 765, 772 by RAPD analysis.No. 740, 544, 765, 772 by RAPD analysis.

• Macromolecular Research
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• v.11 no.1
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• pp.19-24
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• 2003

Polymeric gene delivery system attracts profound attention as it shows less toxicity, versatility, and reasonable gene expression efficiency. Terplex system, a synthetic biopolymeric gene delivery system consisting of stearyl poly-L-lysine (stearyl-PLL) and low density lipoprotein (LDL) was evaluated for its body distribution of gene expression of exogenously administered pDNA after tail-vein injection in mice. Kidney and spleen are two major organs with highest gene expression, whereas liver and heart showed marginal gene expression among the organs examined. Hemolytic effect of the terplex system was evaluated using human red blood cells, where terplex system did not cause significant hemolysis at the concentrations above the experimental ranges, although unmodified PLL or stearyl-PLL without LDL did. Serum stability of terplex system against enzymatic degradation was also significantly enhanced, presumably due to the steric stabilization from the polymers. Based on these findings and along with its high in vitro transfection efficiency, terplex system could serve as a safe and efficient polymeric gene delivery system with many applications for the in vivo gene therapy.

• Applied Microscopy
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• v.48 no.4
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• pp.96-101
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• 2018

The release of nanoscale membrane-bound vesicles is common in all three domains of life. These vesicles are involved in a variety of biological processes such as cell-to-cell communication, horizontal gene transfer, and substrate transport. Prokaryotes including bacteria and archaea release membrane vesicles (MVs) (20 to 400 nm in diameter) into their extracellular milieu. In spite of structural differences in cell envelope, both Gram-positive and negative bacteria produce MVs that contain the cell membrane of each bacterial species. Archaeal MVs characteristically show surface-layer encircling the vesicles. Filamentous fungi and yeasts as eukaryotic microbes produce bilayered exosomes that have varying electron density. Microbes also form intracellular vesicles and minicells that are similar to MVs and exosomes in shape. Electron and fluorescence microscopy could reveal the presence of DNA in MVs and exosomes. Given the biogenesis of extracellular vesicles from the donor cell, in situ high-resolution microscopy can provide insights on the structural mechanisms underlying the formation and release of microbial extracellular vesicles.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.15-15
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• 2001

We recently demonstrated that satellite regions exhibit an aberrant DNA methylation in cloned bovine embryos. Here, we examined, using bisulfite -sequencing technology, whether the inefficient demethylation of cloned donor genomes could be rescued by the presence of oocytic nuclei. Both AciI digestion and sequencing analyses showed that satellite sequence was demethylated more efficiently in cloned tetraploid blastocysts than in diploid clones. When methyl -CpG density (the number of methyl-CpG sites per string) was scored, a significant decrease was observed In tetraploids (P<0.001). These results suggest that unknown mechanisms provided by oocytic nuclei could assist the demethylation of satellite sequences in tetraploid clones.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.325-337
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• 2014

To assess the functional structure of prepro-melanin-concentrating hormone (pMCH), we isolated and cloned pMCH (of-pMCH) mRNA from the brain of the olive flounder, Paralichthys olivaceus, and compared its amino acid sequence with those from other animals. In addition, to examine whether activation of the brain of-pMCH gene is influenced by background color, density, and feeding, we compared pMCH mRNA activities against different background colors (bright and dark) and at different densities (100% PCA and 200% PCA). To examine whether the pMCH gene is related with malpigmentation of blind-side skin and appetite, we compared pMCH gene expression between ordinary and hypermelanic flounders, and between feeding and fasting flounders. The of-pMCH cDNA was 405 bp in the open reading frame [ORF] and encoded a protein of 135 amino acids; MCH was 51 bp in length and encoded a protein of 17 amino acids. An obvious single band of the expected size was obtained from the brain and pituitary by RT-PCR. In addition, of-pMCH gene activity was significantly higher in the bright background only at low density (< 100% PCA) making the ocular skin of fish whitening, and in ordinary fish. However, the gene activity was significantly decreased in dark background, at high density (>200% PCA), and in hypermelano fish. These results suggest that skin whitening camouflage of the flounder is induced by high MCH gene activity, and the density disturbs the function of background color in the physiological color change. Moreover, our data suggest that a low level of MCH gene activity may be related to malpigmentation of the blind-side skin. In feeding, although pMCH gene activity was significantly increased by feeding in the white background, the pMCH gene activity in the dark background was not influenced by feeding, indicating that the MCH gene activity increased by feeding can be offset by dark background color, or is unaffected by appetite. In conclusion, this study showed that MCH gene expression is related to ocular-skin whitening camouflage and blind-skin hypermelanosis, and is influenced by background color and density.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.118-126
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• 2002

To evaluate the correlations of microbial populations with soil healthiness and crop production and establish the criteria for microbial population of soil types. We analyzed the microbial community structure of 13 soils which were different in physical and chemical properties and cultivation methods. According to the analysis of microbial population suing the dilution plate method, the large differences of the microbial population structures among soil types were shown: aerobic bacteria $2-27{\times}10^6$, fluorescent Pseudomonas $1-1,364{\times}10^5$, Gram negative bacteria $1-126{\times}10^4$, and mesophilic Bacillus $1-110{\times}10^5$. The density of Gram negative bacteria was highest on red pepper cultivating soils (sample no. 4 and 6) of Umsung and Gesan, Chungbuk, and the density of the fluorescent Pseudomonas was highest on greenhouse soil (sample no. 7) of Jinju, Kyungnam. The crop productivity of three soils was high as compared with those of other soils. It was supposed that the density of fluorescent Pseudomonas and mesophilic Bacillus were correlated with the incresed crop production. By MIDI analysis, 579 strains isolated from 13 soils composed of a variety of microbes including 102 isolates of Agrobacterium, 112 isolates of Bacillus, 32 isolates of Pseudomonas, 44 isolates of Kocuria, and 34 isolates of Pseudomonas. Among the 624 isolates of Gram negative bacteria, Pseudomonas including P. putida and p. fluorescens occupied the highest density (51%), and Stenotrophomonas maltophilia and Burkholderia cepacia also appeared at high density. From RAPD analysis, the fluorescent Pseudomonas strains isolated from 13 soil types showed a high level of strain diversities and were grouped into 2 - 14 patterns according to soil types. Many of unknown bacteria were recovered from the paddy soil, and needed to be further characterized on the molecular basis.

• Korean Journal of Biological Psychiatry
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• v.14 no.2
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• pp.115-121
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• 2007

Objetives : Identification of target genes for ethanol in neurons is important for understanding its molecular and cellular mechanism of action and the neuropathological changes seen in alcoholics. The purpose of this study is to identify of altered gene expression after acute treatmet of ethanol in rat gliom cells. Methods : We used high density cDNA microarray chip to measure the expression patterns of multiple genes in cultured rat glioma cells. DNA microarrays allow for the simultaneous measurement of the expression of several hundreds of genes. Results : After comparing hybridized signals between control and ethanol treated groups, we found that treatment with ethanol increased the expression of 15 genes and decreased the expression of 12 genes. Upregulated genes included Orthodenticle(Drosophila) homolog 1, procollagen type II, adenosine A2a receptor, GATA bindning protein 2. Downregulated genes included diacylglycerol kinase beta, PRKC, Protein phosphatase 1, clathrin-associated protein 17, nucleoporin p58, proteasome. Conclusion : The gene changes noted were those related to the regulation of transcription, signal transduction, second messenger systems. modulation of ischemic brain injury, and neurodengeneration. Although some of the genes were previously known to be ethanol responsive, we have for the most part identified novel genes involved in the brain response to ethanol.