• The Journal of Korean Physical Therapy
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• v.11 no.3
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• pp.133-140
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• 1999

Why does the CNS not regenerate after injury? The failure of axonal regeneration in the CNS after injury is not due to an inherent inability of these neurons to regrowth axon. Recently, an inhibitory substrate effect of CNS has been discovered which could be directly invoked in the lack of regeneration. The failure of axon regrowth in the CNS is crucially influenced by the presence of neurtie growth inhibitor NI35/250 and possibly also by molecules such as myelin associated glycoprotein(MAG) and chondroitin sulphate proteoglycans(CSPGs). The application of the monoclonal antibody IN-1, which efficinetly neutralizes the N135/250 inhibitory molecules. This new finding has a strong impact on the development of, a new neuroscienctific research directed to stimulate axonal regeneration. In this review summarize the current knowledge on the factors and molecules involved in the regeneration failure.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.889-890
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• 2006

In recent years, PCB drills with smaller diameters less than 0.1 mm are used and thus there are growing needs for ultra-fine grained cemented carbides. However, ultra-fine WC powder usually causes extraordinary grain growth during sintering which weakens mechanical strength of ultra-fine grained cemented carbides. So we examined several kinds of WC powders to make new ultra-fine grained cemented carbides having superior performance. We found that direct carburized WC powder is very good as a WC raw material. The PCB drills made of the developed ultra-fine grained cemented carbides have higher hardness, toughness and stiffness than conventional ones.

• Electrical & Electronic Materials
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• v.9 no.1
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• pp.38-43
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• 1996

A coprecipitation method was used for preparing Ca and Pt doped $SnO_2$ fine powder. Components of the powder were investigated by XPS and SIMS. Crystallite size and specific surface area were investigated by TEM, XRD, and BET analysis. $SnO_2$(Ca)/Pt based thick film devices were prepared by a screen printing technique for methane gas detection. Then sensing characteristics of the devices were investigated. As Ca and Pt added, the crystal growth of $SnO_2$ was suppressed during calcining and sintering, and the sensitivity of $SnO_2$(Ca)/Pt thick film to methane gas was enhanced. For the Pt doped $SnO_2$ fine particle, the thick film device shows sensitivity of about 83% to 2000 ppm methane gas at an operating temperature of >$400^{\circ}C$.

• Journal of Crop Science and Biotechnology
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• v.11 no.3
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• pp.187-192
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• 2008

The effects of some coumarins(coumarin, 7-hydroxycoumarin, scopoletin and esculetin) were investigated on pumpkin(Cucurbita maxima Duch.) seedlings and on pumpkin glutathione S-transferases(GSTs). Coumarin and esculetin suppressed the growth of seedlings, especially the elongation of roots as well as hypocotyls. Among the compounds tested, only esculetin inhibited the activity of a particular pumpkin GST by 50%, CmGSTU3 toward 1-chloro-2, 4- dinitrobenzene(CDNB) and at a concentration of 22 ${\mu}M$. Both ethylacetae(EtOAc) and water fractions in pumpkin seedlings and different organs of one-month-old pumpkin plants contained esculetin or similar hydrophobic fluorescent substances as well as hydrophilic substances, which showed different degrees of inhibitory effects on CmGSTU3 activity.

• Journal of the korean veterinary medical association
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• v.18 no.7
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• pp.27-34
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• 1982

In the experiments of the inhibition of mold growth from October 1, 1981 to March 31, 1982, Mold-X has been shown the effective results as follows; 1. In the storage of the corn and the corn meal contained $12\%$ moisture, the growth of mold wa

• Molecules and Cells
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• v.41 no.12
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• pp.1045-1051
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• 2018

The developmentally regulated GTP binding protein 2 (DRG2) is involved in the control of cell growth and differentiation. Here, we demonstrate that DRG2 regulates microtubule dynamics in HeLa cells. Analysis of live imaging of the plus-ends of microtubules with EB1-EGFP showed that DRG2 deficiency (shDRG2) significantly reduced the growth rate of HeLa cells. Depletion of DRG2 increased 'slow and long-lived' subpopulations, but decreased 'fast and short-lived' subpopulations of microtubules. Microtubule polymerization inhibitor exhibited a reduced response in shDRG2 cells. Using immunoprecipitation, we show that DRG2 interacts with tau, which regulates microtubule polymerization. Collectively, these data demonstrate that DRG2 may aid in affecting microtubule dynamics in HeLa cells.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.561-568
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• 2020

We examined the anticancer effects of a novel sirtuin inhibitor, MHY2256, on HCT116 human colorectal cancer cells to investigate its underlying molecular mechanisms. MHY2256 significantly suppressed the activity of sirtuin 1 and expression levels of sirtuin 1/2 and stimulated acetylation of forkhead box O1, which is a target protein of sirtuin 1. Treatment with MHY2256 inhibited the growth of the HCT116 (TP53 wild-type), HT-29 (TP53 mutant), and DLD-1 (TP53 mutant) human colorectal cancer cell lines. In addition, MHY2256 induced G0/G1 phase arrest of the cell cycle progression, which was accompanied by the reduction of cyclin D1 and cyclin E and the decrease of cyclin-dependent kinase 2, cyclin-dependent kinase 4, cyclin-dependent kinase 6, phosphorylated retinoblastoma protein, and E2F transcription factor 1. Apoptosis induction was shown by DNA fragmentation and increase in late apoptosis, which were detected using flow cytometric analysis. MHY2256 downregulated expression levels of procaspase-8, -9, and -3 and led to subsequent poly(ADP-ribose) polymerase cleavage. MHY2256-induced apoptosis was involved in the activation of caspase-8, -9, and -3 and was prevented by pretreatment with Z-VAD-FMK, a pan-caspase inhibitor. Furthermore, the autophagic effects of MHY2256 were observed as cytoplasmic vacuolation, green fluorescent protein-light-chain 3 punctate dots, accumulation of acidic vesicular organelles, and upregulated expression level of light-chain 3-II. Taken together, these results suggest that MHY2256 could be a potential novel sirtuin inhibitor for the chemoprevention or treatment of colorectal cancer or both.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.769-777
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• 2004

A Helicobacter pylori urease inhibitor from Rubus coreanus Miquel has been isolated and partially characterized for aiming to Prevent H. pylori growth and decrease harmful accumulation of ammonia in human gastric mucosa. We screened urease inhibitory activities in 519 extracts library prepared by solvent extraction from 173 kinds of edible plants, medicinal herbs, herbs and seaweeds using a colorimetric urease assay system. As results of primary and secondary screening, 70% acetone extract of Rubus coreanus Miquel was selected as potent candidate, showing about 24% inhibitory activity. The acetone extract was sequentially partitioned into RCE/RCWI and RCB/RCW2 layers with ethyl acetate and butanol. The major active component in RCW2, water layer from butanol fractionation was revealed to be peptidic or proteinous substance by inhibitory activity determination after pronase digestion and periodate oxidation. RCW2-IIIc a was isolated by sequential column chromatography on DEAE-Toyopearl 650C, Butrl-Toyopearl 650M and Sephadex LH-20. The isolated urease inhibitor RCW2-IIIc $\alpha$, was highly pure proteinous substance with molecular weight of 13kDa by high-performance gel permeation liquid chromatography. RCW2-IIIc$\alpha$ has about 5 times higher inhibitory activity than 70％ acetone extract, showing high stability against heat treatment and peptic digestion.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.160-170
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• 2016

The increasing spread of antibiotic-resistant pathogens has raised the interest in alternative antimicrobial treatments. In our study, the functionally active gram-negative bacterium bacteriophage CP933 endolysin was produced in Nicotiana benthamiana plants by a combination of transient expression and vacuole targeting strategies, and its antimicrobial activity was investigated. Expression of the cp933 gene in E. coli led to growth inhibition and lysis of the host cells or production of trace amounts of CP933. Cytoplasmic expression of the cp933 gene in plants using Potato virus X-based transient expression vectors (pP2C2S and pGR107) resulted in death of the apical portion of experimental plants. To protect plants against the toxic effects of the CP933 protein, the cp933 coding region was fused at its Nterminus to an N-terminal signal peptide from the potato proteinase inhibitor I to direct CP933 to the delta-type vacuoles. Plants producing the CP933 fusion protein did not exhibit the severe toxic effects seen with the unfused protein and the level of expression was 0.16 mg/g of plant tissue. Antimicrobial assays revealed that, in contrast to gram-negative bacterium E. coli (BL21(DE3)), the gram-positive plant pathogenic bacterium Clavibacter michiganensis was more susceptible to the plant-produced CP933, showing 18% growth inhibition. The results of our experiments demonstrate that the combination of transient expression and protein targeting to the delta vacuoles is a promising approach to produce functionally active proteins that exhibit toxicity when expressed in plant cells.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.303-310
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• 2009

Background: Elevated expression of cyclooxygenase-2 (COX-2) and Polo-like kinase-1 (PLK-1) is observed in a wide variety of cancers. Augmented expression of COX-2 and enhanced production of prostaglandin $E_2(PGE_2)$ are associated with increased tumor cell survival and malignancy; COX-2 has been implicated in the control of human non-small cell lung carcinoma (NSCLC) cell growth. PLK-1 siRNA induced the cell death of lung cancer cells and the systemic administration of PLK-1 siRNA/atelocollagen complex inhibited the growth of lung cancer in a liver metastatic murine model. COX-2 and PLK-1 are involved in proliferation and in cell cycle regulation, and there is a significant correlation between their interaction in prostate carcinoma. Methods: In this study, we investigated the pattern of COX-2 and PLK-1 expression in NSCLC, after treatment with IL-1$\beta$, COX-2 inhibitor and PLK-1 siRNA. Results: Expression of PLK-1 was decreased in A549 COX-2 sense cells, and was increased in A549 COX-2 anti-sense cells. Knock out of PLK-1 expression by PLK-1 siRNA augmented COX-2 expression in A549 and NCl-H157 cells. When A549 and NCI-H157 cells were treated with COX-2 inhibitor on a dose-dependent basis, PLK-1 and COX-2 were reduced. However, when the expression of COX-2 was induced by IL-1$\beta$, the production of PLK-1 decreased. Conclusion: These results demonstrate that COX-2 and PLK-1 are regulated and inhibited by each other in NSCLC, and suggest that these proteins have a reverse relationship in NSCLC.