• Archives of Pharmacal Research
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• v.20 no.2
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• pp.155-157
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• 1997

An attempt to estabilish the relationship between anti-cell adhesive action of phenylacetylshikonin analogues and their cytotoxicity against A549 cells was done. In the one hour incubation with A549 cells,${\alpha}$-methoxyphenylacetyl-(9), ${\alpha}$-acetoxyphenylacetyl-(13), 3,4-methylenedioxyphenylacetyl-(15) and 4-(N,N-dimethylamino)-phenylacetylshikonin (17) analogues showed a high anti-cell adhesive activity $(IC_100; value, 4-8{\mu}g/ml)$, while halophenylacetyl- and dimethoxy- or trimethoxyphenylacetyl analogues expressed no activity at $40{\mu}g/ml$, indicating that the presence of a bulky group at $ C^I-{\alpha}$ and a polar group at C-4 of phenylacetyl moiety may be important. A similar structure activity relationship exists for the 48 hr cytotoxocity $(ED_{50})$ of phenylacetylshikonin analogues in A 549 cells, but not in either K562 or L1210 cells. Furthermore, the difference between $IC_{100}$ values for anti-cell adhesive activity and$ED_{50}$ values for cytotoxicity of potent compound in A549 cells was not so great (1.5 to 3 times). Based on these observations, it is proposed that the anti-cell adhesive action of phenylacetylshikonins might be responsible for their cytotoxicity in A549 cells.

• Korean Journal of Materials Research
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• v.21 no.3
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• pp.180-185
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• 2011

This study is aimed to increase the activity of cathodic catalysts for PEMFCs(Polymer Electrolyte Membrane Fuel Cells). we investigated the temperature effect of 20wt% Pt/C catalysts at five different temperatures. The catalysts were synthesized by using chemical reduction method. Before adding the formaldehyde as reducing agent, process was undergone for 2 hours at the room temperature (RT), $40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$ and $100^{\circ}C$, respectively. The performances of synthesize catalysts are compared. The electrochemical oxygen reduction reaction (ORR) was studied on 20wt% Pt/C catalysts by using a glassy carbon electrode through cyclic voltammetric curves (CV) in a 1M H2SO4 solution. The ORR specific activities of 20wt% Pt/C catalysts increased to give a relative ORR catalytic activity ordering of $80^{\circ}C$ > $100^{\circ}C$ > $60^{\circ}C$ > $40^{\circ}C$ > RT. Electrochemical active surface area (EAS) was calculated with cyclic voltammetry analysis. Prepared Pt/C (at $80^{\circ}C$, $100^{\circ}C$) catalysts has higher ESA than other catalysts. Physical characterization was made by using X-ray diffraction (XRD) and transmission electron microscope (TEM). The TEM images of the carbon supported platinum electrocatalysts ($80^{\circ}C$, $100^{\circ}C$) showed homogenous particle distribution with particle size of about 2~3.5 nm. We found that a higher reaction temperature resulted in more uniform particle distribution than lower reaction temperature and then the XRD results showed that the crystalline structure of the synthesized catalysts are seen FCC structure.

• Journal of Nutrition and Health
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• v.36 no.4
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• pp.382-388
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• 2003

(-)-Epigallocatechin-3-gallate (EGCG) is a polyphenolic compound found in peen tea leaves, and has been known to be one of the most potent catechin species which inhibits cell growth most possibly through an apoptotic cell death. We investigated the apoptotic activity of (-)-EGCG on the human myeloid leukemia cell line, HL-60. Our results of MTT test indicated that (-)-EGCG had a significant antiproliferation effect in HL-60 cells with $IC_{50}$/ (50% inhibition concentration) value of 65 $\mu$M. Giemsa statining of HL-60 cells treated with (-)-EGCG (100 $\mu$M) for 6hrs showed a typical apoptosis-specific morphological change including shrinkage of the cytoplasm, membrane blobbing and compaction of the nuclear chromatin. The DNA fragmentation was observed from the agarose gel electrophoresis of cells treated with (-)-EGCG for 3hrs or longer, and was progressed to a greater degree as treatment time increases. Treatment of the cells with (-)-EGCG (100 $\mu$M) resulted in a rapid release of mitochondrial cytochrome c into the cytosol, and a subsequent cleavage of caspase-3 to an active form in a treatment-time dependent manner. (-)-EGCG (100 $\mu$M) also stimulated proteolytic cleavage of poly-(ADP-ribose) polymerase (PARP) to an active form in HL-60 cells. Tlken together, (-)-EGCG appears to induce the apoptosis in human myeloid leukemia cells via a caspase-dependent pathway. These results suggest the possible application of (-)-EGCG, the major active compound in green tea, as an antiproliferative agent for cancer prevention.

• YAKHAK HOEJI
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• v.58 no.2
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• pp.81-90
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• 2014

In order to determine the functional benefits of Cordyceps militaris in the immune system, we examined the immunomodulatory activities of C. militaris using an immunocompromised C57BL/6 mice, mouse spleen cells, RAW 264.7 macrophage cells, and A549 lung carcinoma cells. Mice were injected intraperitioneally with an immunosuppressive drug, cyclophosphamide, and then administered orally with 30, 100 and 300 mg/kg of 50% ethanol extract of C. militaris (CME 30, CME 100 and CME 300) for 14 days. CME increased splenocyte proliferation and natural killer (NK) cell activity compared to 3% hydroxypropyl methylcellulose-treated control mice. CME also increased the production of Th1 cytokines, IL-2 and TNF-${\alpha}$ in spleen cells isolated from CME-injected mice and in vitro, which suggested the enhanced cellular immunity in response to CME. CME also increased splenocyte proliferation, NK cell activity, and IL-2 and TNF-${\alpha}$ production compared to 1 ${\mu}M$ methotrexate-treated spleen cells in vitro. We examined whether C. militaris regulates the production of inflammatory mediators in LPS-stimulated RAW 264.7 cells. CME inhibited LPS-induced NO production and iNOS expression in a dose dependent manner, while COX-2 expression was remained unchanged. In addition, CME also has free radical scavenging activity, indicating its antioxidant activity. These results indicate that C. militaris enhances immune activity by promoting immune cell proliferation and cytokine production.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.80-80
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• 1997

The object of this study was to develop a gene therapy strategy for ovarian cancer. We have previously shown that AV with a L-plastin (LP) promoter infects breast and ovarian cancer cells and expressed ${\beta}$-galactosidase cDNA in preference to normal fibroblast cells and hematopoietic cells. We now report on the cytotoxicity of Ad.LP.CD, an AV carrying a CD cDNA which converts the pro-drug, 5-Fluorocytosine (5-FC) into the toxic drug 5-Fluorouracil (5-FU). Infection of Ad.LP.CD into either 293 cells or ovarian cancer cells generated the functional CD as measured by HPLC analysis. Using a ratio of AV to OVCAR3 cell of 100 and a 5-FC concentration of 100 ${\mu}$M, we achieve an over 95 % of cell growth inhibition. We are using flow cytometry analysis for ${\beta}$ -galactosidase and ovarian cancer associated folate receptor to screen primary ascites samples for infectivity after infection with an adenoviral vector, i.e., Ad.LP.LacZ. This vector system may be of value in the treatment of microscopic disease of ovarian cancer in the peritoneal cavity.

• Nutritional Sciences
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• v.9 no.3
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• pp.152-158
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• 2006

Helicobacter pylori (H. pylori) infection rapidly stimulated either COX-2 or 5-LOX and released arachidonic acid metabolites that have been considered as pivotal mediators in H. pylori-induced inflammatory responses. To determine whether red ginseng extract (RGE) can suppress the biosynthesis of 5(S)-hydroxyeicosatetraenoic acids (HETE), a precursor metabolite of leukotrienes B4 (LTB4) in H. pylori-provoked inflammatory responses in gastric epithelial cells, the biosynthesis of monohydroxy fatty acids was measured using radioactive arachidonic acid and validated by RP-HPLC using non-radioactive AA as substrate in AGS cells cocultured with H. pylori (ATCC 43504) with or without pretreatment of RGE. Among three known major HETEs, H. pylori infection specifically induced the biosynthesis of $^{14}C-5(S)-HETE$ rather than the complex of $^{14}C-15S-/^{14}C-12(S)-HETE$ from $^{14}C-AA$, concomitantly obtained by HPLC(p<0.01). RGE, 1 to $100{\mu}g/ml$, selectively suppressed H. pylori-stimulated $^{14}C-5(S)-HETE$ production implying the attenuation of 5-lipoxygenase activity, of which was similar to known LOX inhibitor NDGA $(10{\mu}M)$ (p<0.01). However, the amount of 5(S)-HETE was significantly reduced by higher dose of RGE $(100{\mu}g/ml)$ (p<0.05). These results indicated that LOX pathway might be one of principle pathogenic mechanisms of H. pylori and red ginseng could be a nutraceutical against H. pylori infection through inhibiting action of LOX activity.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.720-726
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• 1996

The neurotoxicity induced by L-glutamate in primary cultures of rat cortical cells could be attenuated by diterpene constituents of Ginkgo biloba leaves, ginkgolides A, B and C. At the concentration of 100 nM, ginkgolides up-regulated the activity of glutathione reductase in primary cultures of rat cortical cells exposed to 100 ${\mu}$M glutamate. Furthermore, ginkgolides increased the content of reduced glutathione in glutamate-treated cortical cells. However, ginkgolides showed little effect in reducing superoxide dismutase activity. Ginkgolides did, however, markedly block the production of malondialdehyde, a byproduct of lipid peroxidation in glutamate-treated rat cortical cells.

• YAKHAK HOEJI
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• v.41 no.1
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• pp.111-116
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• 1997

The neurotoxicity induced by L-glutamate in primary cultures of rat cortical cells could be attenuated by sesquiterpene constituent of Ginkgo biloba leaves, bilobalide. At the c oncentration of 100 nM, Bilobalide elevated the combined levels of reduced/oxidized glutathione in rat cortical cells exposed to 100 ${\mu}$M glutamate. Furthermore, bilobalide promoted a reduction in superoxide dismutase activity in glutamate-treated cells. Finally, bilobalide markedly inhibited the production of malondialdehyde. a measure of lipid peroxidation, in glutamate-treated rat cortical cells.

• IMMUNE NETWORK
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• v.7 no.2
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• pp.95-100
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• 2007

Background: A red seaweed, Callophyllis japonica has been traditionally eaten in the oriental area. In a recent study, it has been demonstrated that the ethanol extract of C. japonica have antioxidant activity. However, there are few studies about the effects of C. japonica on the function of immune cells. We investigated the immunomodulatory effects of C. japonica on the function of dendritic cells, the potent antigen-presenting cells. Methods: Bone marrow-derived dendritic cells (DCs) were used and the viability was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and trypan blue exclusion test. Cytokine and nitric oxide (NO) levels were determined by using ELISA and Griess reagent, respectively. The expression levels of DC surface markers were measured by flow cytometric analysis. Results: C. japonica ethanol extract did not significantly affect the DCs viability and the IL-12 production from DCs, irrespective of the presence of lipopolysaccharide (LPS). In addition, it did not significantly change the expression of DC surface markers. However, C. japonica ethanol extract significantly inhibited the LPS-induced NO production and also increased the proliferation of allogeneic lymphocytes activated by DCs. Conclusion: Our data suggests that C. japonica ethanol extract enhances the proliferation of allogeneic lymphocytes activated by DCs which is associated with inhibition of NO production from DCs induced by LPS.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.36-39
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• 2003

Many defined cell culture media were formulated over 3() years ago and may be deficient in certain micronutrients whose essentiality has only subsequently been recognised. The objective of this study was to evaluate whether alpha-minimal essential medium (MEM) supplemented with 10% foetal bovine serum contained sufficient selenium for optimal activity of the selenium containing enzymes cytosolic glutathione peroxidase (cGPx) and phospholipid hydroperoxide glutathione peroxidase (PHGPx) in cultured Chinese hamster ovary (CHO) cells. Additionally, the effect of zinc deficiency and metallothionein (MT) overexpression on cGPx and PHGPx activity was studied. The addition of 100 nM of selenous acid to the culture medium increased cGPx expression by 10-fold and PHGPx by about 2-fold in both wild-type CHO-K1 cells and CHO-K1 cells overexpressing mouse MT-1. Zinc deficiency had no significant effect on enzyme activity, but cells overexpressing mouse MT-1 had higher levels of cGPx activity. Zinc deficiency decreased cell survival but overexpression of MT-1 was partially protective, probably because its presence in quantity favoured the uptake, sequestration and cellular retention of any remaining zinc. This study demonstrates that selenium in complete alpha-MEM is insufficient for optimal cGPx and PHGPx activity and may compromise the cellular response to oxidative stress.