• BMB Reports
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• v.37 no.4
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• pp.480-486
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• 2004

Brain ischemia brings about hypoxic insults. Hypoxia is one of the major pathological factors inducing neuronal injury and central nervous system infection. We studied the involvement of mitogen-activated protein (MAP) kinase in hypoxia-induced apoptosis using cobalt chloride in C6 glioma cells. In vitro cytotoxicity of cobalt chloride was tested by MTT assay. Its $IC_{50}$ value was $400\;{\mu}M$. The DNA fragment became evident after incubation of the cells with $300\;{\mu}M$ cobalt chloride for 24 h. We also evidenced nuclear cleavage with morphological changes of the cells undergoing apoptosis with electron microscopy. Next, we examined the signal pathway of cobalt chloride-induced apoptosis in C6 cells. The activation of extracellular signal-regulated protein kinase 1/2 (ERK 1/2) started to increase at 1 h and was activated further at 6 h after treatment of 400 M cobalt chloride. In addition, pretreatment of PD98059 inhibited cobalt chloride-induced apoptotic cell morphology in Electron Microscopy. These results suggest that cobalt chloride is able to induce the apoptotic activity in C6 glioma cells, and its apoptotic mechanism may be associated with signal transduction via MAP kinase (ERK 1/2).

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.667-673
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• 1998

Rebar corrosion in a simulated pore solution (SPS) with chloride ion was analyzed by Tafel and AC impedance method and corrosion effects of surface roughness and iron oxide layer were also investigated. Corrosion estimation of rebar by electrochemical impedance spectroscopy is very useful, and the measured value can be adapted to proposed electrochemical equivalent circuit model. Corrosion potential increased to the cathodic direction as the concentration of chloride ions increased and corrosion current had the same tendency as above. Surface films were analyzed with scanning electron microscope and Auger electron spectroscopy. Thermally oxidized layer by torch flame for 15 sec was very poor at anti-corrosive property. The corrosion rate of rebar increased as the surface roughness increased. Also, higher temperatures above RT of SPS in initial stage caused a rebar to be corroded faster.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.682-687
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• 2018

We investigated the effects of a highly saline solution (HS) containing hypochlorous acid, calcium chloride ($CaCl_2$), and phosphoric acid ($H_3PO_4$) on cell death and growth rate of laver Porphyra yezoensis and green laver Ulva intestinalis. Cell death rates of laver treated with HS and HS plus hypochlorous acid (HS + HOCl) in the harvesting stage were less than 0.5%, and there were no significant differences between the HS and HS + HOCl treatments. However, cell death of green laver treated with HS + HOCl in the harvesting stage was greater than 81.2%. These results indicate that the addition of HOCl is highly effective to eradicate noxious green laver without causing damage to laver. The addition of HOCl and $H_3PO_4$ to HS did not increase the area or weight of laver blades. A combination treatment of $CaCl_2$ and HS, however, significantly increased the area and weight of laver lades compared to controls (P<0.05).

• Textile Coloration and Finishing
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• v.7 no.4
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• pp.54-60
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• 1995

Cellulose(cell)/dimethylacetamide(DMAc)/lithium chloride(LiCl) solutions were prepared and spun to fibers in coagulants. Then, obtained fibers were annealed in appropriate chemicals. The fibers from cell/DMAc/LiCl showed cell III morophology prior to annealing without differenciating the kind of coagulants. Morphology of crystallite, however, was affected by annealing. Annealed fibers at 17$0^{\circ}C$ showed cell IV morphology and had better mechanical properties than others.

• Molecules and Cells
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• v.27 no.5
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• pp.533-538
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• 2009

Heat shock protein 27 (Hsp27) is a molecular chaperone protein which regulates cell apoptosis by interacting directly with the caspase activation components in the apoptotic pathways. With the assistance of the Tat protein transduction domain we directly delivered the Hsp27 into the myocardial cell line, H9c2 and demonstrate that this protein can reverse hypoxia-induced apoptosis of cells. In order to characterize the contribution of Hsp27 in blocking the two major apoptotic pathways operational within cells, we exposed H9c2 cells to staurosporine and cobalt chloride, agents that induce mitochondria-dependent (intrinsic) and -independent (extrinsic) pathways of apoptosis in cells respectively. The Tat-Hsp27 fusion protein showed a greater propensity to inhibit the effect induced by the cobalt chloride treatment. These data suggest that the Hsp27 predominantly exerts its protective effect by interfering with the components of the extrinsic pathway of apoptosis.

• The Korean Journal of Zoology
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• v.36 no.2
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• pp.264-275
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• 1993

서식수 염분농도의 변화에 따른 guppy(Poecilia reticulotus) 아가미 상피내 염소세포(chloride cell)의 미세구조적 변화를 전자현미경으로 관찰하고, 특히 증가하는 염분농도에 따라 주요변화를 보여주는 염소세포내 미토콘드리아와 tubular system의 면적을 영상 분석기로 측정하여 다음의 결과를 얻었다. 염소세포는 주로 guppy 아가미궁의 일차 총판상피에 위치하는데 담수에서는 하나씩 독립적으로 존재하며 자유면이 apical pit를 형성하여 외부환경에 노출되는 반면. 서식수의 염분농도가 증가하면 여러개의 염소세포들이 다세포복합체를 형성하고 이 세포들의 자유면이 함께 하나의 apical pit를 구성하게 된다. 서식수의 염분농도가 증가함에 따라 염소세포내의 미토콘드리아와 tubular system은 점점 더 조밀하게 분포하는 것으로 관찰되었다 염소세포의 단위면적당 미토콘드리아가 차지하는 면적은 서식수가 담수(0%의 염분농도)인 경우는 24$\pm$5%였고, 1%에서는 26$\pm$5%, 2%에서는 33$\pm$7% 그리고 해수(3.2% 염분농도)에 적응된 경우는 42$\pm$7%로 담수환경의 것과 비교하여 약 18%까지 증가하였다 또한 염소세포의 측면과 기저측 세포막 함입의 결과로 형성되는 tubular system은 세포의 단위면적당 차지하는 면적이 담수에 적응된 개체들에서 38$\pm$9%였고 서식환경의 염분농도에 따라 점차 증가하다가 해수에서는 61$\pm$9%로 약 16%까지 높아졌다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.106-106
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• 2018

Cyanidin 3 - rutinoside chloride (CRC) is major anthocyanin, found in Schisandra chinensis, is known to have antioxidant, anticancer, anti-inflammatory, tonic, and anti-aging effects in Korea, China and Japan. In the present study, the human mast cell line (HMC-1) was used to investigate the effects on the production of pro-inflammatory mediators. In this study, CRC showed no cytotoxicity in HMC-1. CRC significantly inhibited the secretion of inflammatory cytokines such as tumor necrosis factor $(TNF)-{\alpha}$ and interleukin (IL)-6 in PMA plus A23187 cacium ionophore (PMACI)-stimulated HMC-1 cells. In addition, CRC suppressed the serum levels of IgE. Furthermore, CRC decreased the PMACI- stimulated phosphorylation of mitogen activated protein kinases (MAPKs) such as p-ERK, p- JNK and p-P38. These results indicate that the pharmacological actions of CRC suggest their potential activity for treatment of allergic inflammation through the down-regulation of mast cell activation.

• Archives of Pharmacal Research
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• v.29 no.8
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• pp.645-650
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• 2006

Tributyltin chloride (TBTC) at concentrations of $0.5-1.0\;{\mu}M$ inhibits dopamine biosynthesis in PC12 cells. In this study, the effects of TBTC on L-3,4-dihydroxyphenylalanine (L-DOPA)-induced cytotoxicity in PC12 cells were investigated. TBTC at concentrations up to $1.0\;{\mu}M$ neither affected cell viability, nor induced apoptosis after 24 or 48 h in PC12 cells. However, TBTC at concentrations higher than $2.0\;{\mu}M$ caused cytotoxicity through an apoptotic process. In addition, exposure of PC12 cells to non-cytotoxic (0.5 and $1.0\;{\mu}M$) or cytotoxic $(2.0\;{\mu}M)$ concentrations of TBTC in combination with L-DOPA (20, 50 and $100\;{\mu}M$) resulted in a significant increase in cell loss and the percentage of apoptotic cells after 24 or 48 h compared with TBTC or L-DOPA alone. The enhancing effects of TBTC on L-DOPA-induced cytotoxicity were concentration- and treatment time-dependent. These data demonstrate that TBTC enhances L-DOPA-induced cytotoxicity in PC 12 cells.

• Biomedical Science Letters
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• v.14 no.3
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• pp.187-192
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• 2008

To clerify the protective effect of omega-3 of polyunsaturated fatty acid docosahexaenoic acid (DHA) on the cytotoxicity induced by organic mercury in cultured NIH3T3 fibroblasts. The measurement of cell viability on ogranic mercury wad done by XTT assay after NIH3T3 fibroblasts were cultured with various concentrations of methyl mercuric chloride (MMC). And also, the effect of DHA on the MMC-mediated cytotoxicity was examined by cell viability, and antioxidant effect of DHA was also assessed by superoxide dismutase (SOD)-like activity and the lipid peroxidation activity in cultured NIH3T3 fibroblasts. In this study, MMC decreased cell viability and $XTT_{50}$ value was determined at $50{\mu}M$ of MMC in these culture. In the effect of DHA against the cytotoxicity induced by MMC, DHA significantly increased the cell viability damaged by MMC in cultured NIH3T3 fibroblasts. And also, DHA showed the antioxidant effect by showing the increase of SOD-like activity and the decrease of lipid peroxidation activity. From these results, it is suggested that organic mercury such as MMC has highly toxic effect on cultured NIH3T3 fibroblasts, and also, omega-3 of polyunsaturated fatty acid, DHA showed the protection on MMC-induced cytotoxicity and antioxidant effect.

• Biomedical Science Letters
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• v.13 no.4
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• pp.355-360
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• 2007

In order to evaluate on the cytotoxicity of methyl mercury (MM) and antioxidant effect of phenolic compound, poncirin against MM-induced cytotoxicity, XTT assay was performed to determine the cell viability after human skin fibroblasts (Detroit 51) were grown in the media containing various concentrations of methylmercuric chloride (MMC). And also, the antioxidant effect of poncirin on the cytotoxicity induced by MMC was examined by cell viability and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in these cultures. MMC decreased cell viability in dose-dependent manner in these cultures and the midcytotoxicity value was determined at concentration of 30 ${\mu}M$ MMC after human skin fibroblasts were treated with $10\sim50{\mu}M$ MMC for 72 hours, respectively. MMC was highly toxic on cultured human skin fibroblasts by toxic criteria. MMC-mediated cytotoxicity was related with oxidative stress by the diminution of toxic effect according to the treatment of vitamin E. In the antioxidant effect of poncirin, it showed vitamin E-like DPPH radical scavenging activity at 90 ${\mu}g/ml$ poncirin and also, remarkably increased cell viability compared with MMC-treated group. From these results, it is suggested that MMC-mediated cytoxicity was highly toxic and was related with oxidative stress in cultured human skin fibroblasts, and also phenolic compound such as poncirin showed the protection on MMC-induced cytotoxicity by antioxidant effect in these cultures.