• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.357-364
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• 2017

In this study, we aimed to generate a series of versatile tagging plasmids that can be used in diverse molecular biological studies of the fungal pathogen Cryptococcus neoformans. We constructed 12 plasmids that can be used to tag a protein of interest with a GFP, mCherry, $4{\times}FLAG$, or $6{\times}HA$, along with nourseothricin-, neomycin-, or hygromycin-resistant selection markers. Using this tagging plasmid set, we explored the adenylyl cyclase complex (ACC), consisting of adenylyl cyclase (Cac1) and its associated protein Aca1, in the cAMP-signaling pathway, which is critical for the pathogenicity of C. neoformans. We found that Cac1-mCherry and Aca1-GFP were mainly colocalized as punctate forms in the cell membrane and non-nuclear cellular organelles. We also demonstrated that Cac1 and Aca1 interacted in vivo by co-immunoprecipitation, using $Cac1-6{\times}HA$ and $Aca1-4{\times}FLAG$ tagging strains. Bimolecular fluorescence complementation further confirmed the in vivo interaction of Cac1 and Aca1 in live cells. Finally, protein pull-down experiments using $aca1{\Delta}$::ACA1-GFP and $aca1{\Delta}$::ACA1-GFP $cac1{\Delta}$ strains and comparative mass spectrometry analysis identified Cac1 and a number of other novel ACC-interacting proteins. Thus, this versatile tagging plasmid system will facilitate diverse mechanistic studies in C. neoformans and further our understanding of its biology.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.667-679
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• 1996

Clonal forestry and reforestation programmes are especially interested now in development and application of controllable biotechnological systems based on the production of conifer somatic embryos in bioreactors with their following drilling and/or storage in the form of "artificial seeds". Modern achievements in conifer somatic embryogenesis has guided the development not only of biotechnological systems in forestry, but also of basic research in conifer embryology, cell and molecular biology. At the present time, the level of development of applied research on conifer somatic embryogenesis is well ahead our understanding of this complex phenomenon. The "bottleneck" situation in relation between basic and applied sciences will eventually lead to the appearance of "weak points" in biotechnological systems. In the present review, the major advances and the most pressing problems in the application of conifer somatic embryogenesis both to forest biotechnology and to basic research are in the focus of attention.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.602-607
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• 2017

Background: Panax ginseng is a traditional herb used for medicinal purposes in eastern Asia. P. ginseng contains various ginsenosides with pharmacological effects. In this study, floralginsenoside A (FGA), ginsenoside Rd (GRD), and ginsenoside Re (GRE) were purified from P. ginseng berry. Methods: Chemical structures of FGA, GRD, and GRE were determined based on spectroscopic methods, including fast atom bombardment mass spectroscopy, ID-nuclear magnetic resonance, and infrared spectroscopy. Inhibitory activities of these compounds on melanogenesis were studied by measuring the expression of protein and melanin content in the melan-a cell line. This inhibitory activity was confirmed by observing pigmentation and tyrosinase activities of zebrafish. Results: GRD, GRE, and FGA were not cytotoxic at concentrations less than $20{\mu}M$, $80{\mu}M$, and $160{\mu}M$ in melan-a cells, respectively. GRD, GRE, and FGA inhibited melanin biosynthesis in melan-a cells by 15.2%, 22.9%, and 23.9% at $20{\mu}M$, $80{\mu}M$, and $160{\mu}M$, respectively. FGA was observed to display the most potent inhibitory effect. In addition, FGA decreased microphthalmia-associated transcription factor protein expression in a dose-dependent manner. Moreover, FGA induced extracellular signal-regulated kinase phosphorylation level in melan-a cells. In addition, melanin pigment content and tyrosinase activity in zebrafish treated with FGA at $160{\mu}M$ were reduced. Conclusion: FGA showed the most potent inhibition of melanogenesis in both in vitro and in vivo studies. This study suggests that FGA purified from P. ginseng may be an effective melanogenesis inhibitor.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.41-50
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• 2008

Purpose: Bone morphogenetic protein-2(BMP-2) has been shown to possess significant osteoinducitve potential. There have been attempts to overcome a limitation of mass production, and economical efficiency of BMP. The aim of this study was to produce recombinant human BMP-2(rhBMP-2) from E. coli in a large scale and evaluate its biological activity. Materials and Methods: The E.coli strain BL21(DE3) was used as a host for rhBMP-2 production. Dimerized rhBMP-2 was purified by affinity chromatography using Heparin column. To determine the physicochemical properties of the rhBMP-2 expressed in E. coli, we examined the HPLC profile and performed Western blot analysis. The effect of the purified rhBMP-2 dimer on osteoblast differentiation was examined by alkaline phosphatase (ALP) activity and representing morphological change using C2C12 cell. Results: E. coli was genetically engineered to produce rhBMP-2 in a non-active aggregated form. We have established a method which involves refolding and purifying a folded rhBMP-2 dimer from non-active aggregates. The purified rhBMP-2 homodimer was characterized by SDS-PAGE as molecular weight of about 28kDa and eluted at 34% acetonitrile, 13.27 min(retention time) in the HPLC profile and detected at Western blot. The purified rhBMP-2 dimer stimulated ALP activity and induced the transformation from myogenic differentiation to osteogenic differentiation. Conclusion: rhBMP-2 was produced in E. coli using genetic engineering. The purified rhBMP-2 dimer stimulated ALP activity and induced the osteogenic differentiation of C2C12 cells.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.218-221
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• 2017

A solitary fibrous tumor is a relatively uncommon neoplasm that usually occurs in the pleura but occurs extremely rarely in the oral cavity. Reported herein is a rare case of a solitary fibrous tumor in the buccal cheek mucosa. A 50-year-old man visited the authors' hospital due to a buccal cheek mass whose size had increased. Excisional biopsy was done under local anesthesia. After the excisional biopsy, the patient was diagnosed to have a solitary fibrous tumor. In immunohistochemistry, the patient's solitary fibrous tumor was characterized by the expression of CD34 and CD99 on the neoplastic cells, and negativity for Bcl-2 and S-100. No recurrence or complication occurred for a period of 5 years. The growth of a primary solitary fibrous tumor in the buccal cheek mucosa is extremely rare and has been rarely reported in the South Korean medical literature. A solitary fibrous tumor must be distinguished from other spindle cell tumors. Presented herein is a case of primary solitary fibrous tumor in the buccal cheek mucosa. The relevant literature is briefly reviewed.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.445-448
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• 2005

A new high efficiency phase shifted full bridge (PSFB) converter for sustaining power module of plasma display panel (PDP) is proposed in this paper .The proposed converter employs the rectifier of voltage doubler type without output inductor. Since it has no output inductor, the voltage stresses of the secondary rectifier diodes can be clamped at the level of the output voltage. Therefore, no dissipative resistor-capacitor (RC) snubber for rectifier diodes is needed and a high efficiency as well as low noise cutout voltage can be realized. In addition, due to elimination of the large output inductor, it features a simple structure, lower cost, less mass, and lighter weight. Furthermore, the proposed converter has wide zero voltage switching (ZVS ) ranges with low current stresses of the primary switches. Also the resonance between the leakage inductor of the transformer and the capacitor of the voltage doubler cell makes the current stresses of the primary switches and rectifier diodes reduced. In this paper, the operational principles, analysis of the proposed converter, and the experimental results are presented.

• Korean Chemical Engineering Research
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• v.55 no.2
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• pp.230-236
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• 2017

Solubility data of carbon dioxide ($CO_2$) in poly(ethylene glycol) dimethyl ether (PEGDME) are presented at pressures up to about 50 bar and at temperatures between 303 K and 343 K. The solubilities of $CO_2$ were determined by measuring the bubble point pressures of the $CO_2+PEGDME$ mixtures with various compositions using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. To observe the effect of the PEGDME molecular weight on the $CO_2$ solubility, the $CO_2$ solubilities in PEGDME with two kinds of molecular weight were compared. As the equilibrium pressure increased, the $CO_2$ solubility in PEGDME increased. On the other hand, the $CO_2$ solubility decreased with increasing temperature. When compared at the same temperature and pressure, the PEGDME with a higher molecular weight gave smaller $CO_2$ solubility on a mass fraction and molality basis, but gave greater $CO_2$ solubilities on a mole fraction basis.

• KSBB Journal
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• v.9 no.3
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• pp.299-305
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• 1994

Taxol contents in various parts of 15 years old yew tree were determined. The descending order of taxol content per unit mass was stem bark, root bark, needle and seed. In the seed, that order was seed coat, embryo and endosperm. The total amount of taxol extractable from a 15 years old yew tree was 1.68 gram. This amount was distributed in needle, stem bark, root bark and seeds as 48.0, 23.8, 27.9 and 0.4%, respectively. Altitudinal variation of taxol content was also observed. More taxol was observed in yew trees grown at high altitude over 1000m above sea level. Calli and suspension cultures were induced from various yew trees. The presence of taxo] in cultured cells was established bv HPLC. The taxol content in cultured cells were different according to the source of explants. These results may be useful for the goal of large scale taxol production by cultured yew tree cells.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.60-66
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• 1994

Among the various bacterial isolates from municipal sewages which utilized linear alkylbenzene sulfonate (LAS) as a sole source of carbon. 3 potent strains - KL-3, SH-2 and EN-1 - were selected. The strains were classified: KL-3 as a strain belong to the genus Klebsiella; SH-2 Shigella; and EN-1 Enterobacter, respectively. They were grown in a broth containing 200 ppm of LAS, using a laboratory scale fermentor: the bacterial growth reached stationary phase after 2 days with a maximum viability of $10^8cfu/mL$ of the culture; initial rates of LAS degradation were high during the first 24 hours of cultivation (KL-3 and SH-2, approx. 50%; EN-1, 20%); after 1 day a lag period of about 24 hours was observed for all the strains, and thereafter break-down proceeded rapidly; final rates after 7 days were approximately 85% by KL-3, 82% by SH-2 and 75% by EN-1. Adsorption of LAS by the bacterial cell mass was high for the strain SH-2, as Freundlich equation: Y= 0.030X + 0.95 was calculated.

• Journal of Haehwa Medicine
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• v.9 no.2
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• pp.251-268
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• 2001

We arrived at the following conclusion after we have studied crohn's disease through the literatures of western and oriental medicine. 1. Crohn's disease has a characteristic of granulomatous necrosis and cicatricial inflammation which is called by segmental enteritis, granulomatous enteritis. This falls under the category of "Diarrhea", "Dysentery" and is similar to "small intestinal diarrhea", "acute temesmus", "splenic diarrhea" in oriental medicine. 2. In western medicine, the cause of crohn's disease indefinites, but it is presumed immunological unbalance of alimentary canal. In oriental medicine, it is summarized as the abnormal ascending and descending circulation of stomach and splenic energies, the hepatic stagnation, being the lower part of cleaning qi by exogenous disease, dyspeptic convulsion. 3. The presenting symptoms of crohn's disease are intermittent chronic diarrhea, fever, weight loss, abdominal spastic pain or abdominal discomfort. When anyone has a abdominal mass, a rectal abcess, and a rectal constriction by physical examination, we can doubt crohn's disease. 4. The methods of western medical treatment are a suppression of intestinal toxic contents and inflammatory mediator, a supply of nutritive substanceus to intestinal epithelial cell. Oriental medical treatments of these are "inducing diuresis", "warming kidney to reinforce yang", "nourishing qi to invigorate spleen", "eliminatin dampness by cooling" according to syndrome differentiations. As mentioned above, we can confirm possibility of oriental medical treatment that induces recovery of immunologic control function and we need advanced experiment, study, and clinical approach.