• YAKHAK HOEJI
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• v.53 no.1
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• pp.1-5
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• 2009

This study was performed to investigate the effects of acteoside and isoacteoside isolated from Clerodendron trichotomum Thunberg on melanin production in B16 melanoma cells. In DPPH radical scavenging activity, acteoside and isoacteoside had a potent anti-oxidant activity in a dose-dependent manner. Both acteoside and isoacteoside dose-dependently inhibited silica-induced ROS (reactive oxygen species) generation in B16 melanoma cells. They significantly inhibited tyrosinase activity and melanin production in MSH-stimulated B16 melanoma cells. The inhibitory effect of acteoside was more potent than that of isoacteosidee. In Western blot of tyrosinase, acteoside inhibited MSH-induced tyrosinase expression in B16 melanoma cells, which is related to the inhibitory action of acteoside on tyrosinase activity and melanin production. These results show that acteoside and isoacteoside from Clerodendron trichotomum Thunberg has a potent antioxidant activity and whitening activity. The underlying mechanism of acteoside on whitening activity may be due to the inhibition of tyrosinase activity and tyrosinase expression.

• Journal of fish pathology
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• v.24 no.2
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• pp.141-152
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• 2011

Growth, oxidative stress and antioxidant capacity of Fucus serratus exposed to high doses of Cd were examined. Two sites in Southwest England (Restronguet Point and Bantham Quay) were selected since they had different histories of metal contamination. 1~10 mg Cd $L^{-1}$ were treated to Aquil medium for up to 14 days. Similar levels of lipid peroxidation but different values of relative growth rates, cupric ion reducing antioxidant capacity (CUPRAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging capacity indicated that F. serratus has population-dependent antioxidant strategies. F. serratus demonstrated cadmium resistance with no visual symptoms for 14 days and the population from the polluted area seemed to have more powerful antioxidant strategies. However Fucus from the conserved area also showed protective anti oxidative mechanism.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.5
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• pp.467-479
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• 2020

Various researches are being conducted to reduce greenhouse gases generated by the consumption of traditional energy resources. This study was conducted to numerically analyze the combustion characteristics and N-S reaction behavior with respect to the H₂ content of syngas composed of CO and H₂ in pressurized air combustion. A non-premixed opposed flow flame model was applied a modified detailed mechanism with S-chemistry was developed based on GRI 3.0 to simulate the syngas reaction. As the hydrogen content increased, the flame thickness increased due to the fast reactivity of hydrogen. In the rich region, NO and SO₂ were reduced by reaction with H radical and H bonding of NO was suppressed by the formation of HOSO.

• BMB Reports
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• v.36 no.2
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• pp.190-195
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• 2003

The Vitamin E (VE) effect was examined on oxidative damage to DNA, lipids, and protein in mice that were fed various levels of lipid diets after total body irradiation (TBI) with X-rays at 2 Gy. No increase of 8-hydroxydeoxyguanosine (8OHdG) by TBI was observed in the +VE group; however, in the case of the -VE group, a significantly higher 8OHdG level was observed in the high-lipid group than in the low- or basal-lipid group. In the groups with TBI, the concentration of thiobarbituric reactive substances (TBARS) only significantly increased in the high-lipid (-VE) group. These changes in TBARS, due to TBI, were not detected in other groups. The contents of protein carbonyls only increased in the (-VE) group. The contents of protein carbonyls was significantly different between the (+VE) and the (-VE) groups, regardless of the lipid levels. The concentrations of GSH, vitamins C and E in the liver were lower, and the concentration of non-heme iron in the liver was higher in the high-lipid group than in the low- and basal-lipid groups. These concentrations in the high-lipid group were significantly different between the (+VE) and the (-VE) groups. These results strongly suggest that mice that are fed a high-lipid diet are susceptible to TBI-induced oxidative damage. Also, decreases in the GSH levels and an increase in the iron level are involved in the mechanism of this susceptibility.

• Toxicological Research
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• v.11 no.2
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• pp.303-308
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• 1995

Nitric oxide, a physiological transmitter, is reported to mediate cellular injury in various tissues. Its reactivity to free radical is believed to be one of the reasons for its involvement in cytotoxicity. Menadione, a representative quinone, is cytotoxic to several cell systems including isolated hepatocyte, endothelial cell and red blood cells. Its toxic mechanism is related to oxidative stress, mediated by toxic free radicals. Our previous studies demonstrated that menadione induced cell lysis and increase of oxygen consumption in platelets. It has been reported that platelets have nitric oxide producing enzyme, nitric oxide synthase. Thus, we have investigated to manifest the role of nitric oxide.in menadione-induced cytotoxicity in rat platelets. Menadione induced cytotoxicity in platelets was unaffected by $N^G$-nitro-arginine methyl ester (L-NAME), selective and competitive inhibitor of nitric oxide synthase. We also invesitgated the role of extracellular nitric oxide in menadione-induced cytotoxicity of platelets by addition with sodium nitroprusside (SNP). SNP did not affect platelet cytotoxicity by menadione. These results suggested that nitric oxide which was generated endogeneously or exogeneously might have a negligible role in menadione-induced cytotoxicity in rat platelets.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.61-65
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• 1993

To find out the mechanisms of anticancer effect of ginseng, we performed prospective randomized study for the 39 patients with stomach cancer who had undergone radical subtotal or total gastrectomy and postoperative immunochemotherapy with PMF from July 1991 to November 1991 at Department of Surgery, Seoul National University Hospital. The patients were randomly divided into study and control group: the study group was administered with powdered red ginseng of 5400mg daily dose for 12 months postoperatively, the control group was simply followed-up. There were no significant differences between study and control group in twelve months postoperative body weights, triceps skin fold, hemoglobin. albumin, total protein, PNI, total WEC and lymphocyte count, and T-cell percentage (p>0.05). The results of preoperative DNCB skin test of study group was (0) for 8 patients and (+) for 12 patiens. but after operation, it showed the tendency of decreasing (0) and (+) ratio and increasing tendency of (++) ratio (p<0.05), but those of control group showed no increasing tendency of the degree of positive DNCB skin test. From the above results, we could conclude that ginseng had anti - cancer effect by the way of immune mechanism and could be an adjunct to the patients with stomach cancer postoperatively.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.1
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• pp.33-39
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• 2016

Alzheimer's disease(AD), one of the most common forms of dementia, is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of β-amyloid(Aβ) peptides of 40-42 residues. Aβ has been believed to be neurotoxic and now is also considered to have a role on the mechanism of memory dysfunction. Only a few acetylcholinesterase(AChE) inhibitors have been developed for treatment of AD, although the numbers of patients are rapidly increasing within aging society. Here, we show that ethanol extract of Rosae Rugosae Flos(RR) or its butanol fraction reduce the enzyme activity of AChE and BACE1(β-site APP cleaving enzyme 1). Furthermore, We found that RR inhibits Aβ aggregation and removes Aβ aggregates by Transmission electron microscopy(TEM). In addition, RR reduces the free radical of 2, 2-diphenyl-1-picrylhydrazyl(DPPH). We suggest that Rosae Rugosae Flos may be useful as a herbal medicine to treat AD.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.5
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• pp.699-706
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• 2012

The water extract of Younggyechulgam-tang (YGCGT) has been traditionally used in treatment of tinnitus in Oriental Medicine. However, little is known about the mechanism by which YGCGT rescues ototoxicity. The purpose of the present study is to investigate the protective effect of YGCGT against cisplatin-induced toxicity in HEI-OC1 auditory cells, organotypic cultures of cochlear explants from three-day postnatal rats (P3). Pretreatment with YGCGT ameliorated apoptotic death induced by cisplatin in HEI-OC1 cells and organotypic cultures of Corti's organ. YGCGT pretreatment also significantly suppressed cisplatin-induced increases in intracellular reactive oxygen species (ROS). Treatment with YGCGT resulted in an increased expression of HO-1 and Bcl-2. These results suggest that YGCGT induced HO-1 signaling pathway, which ultimately prevents free radical stresses from cisplatin and further contributes to protect auditory sensory hair cells from free radicals produced by cisplatin.

• Advances in Traditional Medicine
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• v.7 no.3
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• pp.217-228
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• 2007

Agrimonia pilosa Ledeb. has long been used for a useful natural agent ameliorating inflammation related symptoms in the folk medicine recipe. This study was performed to investigate effects of Agrimonia pilosa Ledeb.(AP) on the expression of inflammation related genes such as the inducible nitric oxide synthase (iNOS) in macrophage cell line, RAW 264.7 cells. The AP (whole plants) was extracted with 80% ethanol and sequentially partitioned with solvents in order to increase polarity. Among the various solvent extracts of AP, the n-butanol (BuOH) fraction showed the most powerful inhibitory ability against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells without affecting cell viability. Reverse transcriptase-polymerase chain reaction and Western blot analysis revealed that the BuOH fraction provided a primary inhibitor of the iNOS protein and mRNA expression in LPS-induced RAW 264.7 cells. The DPPH and OH radical scavenging activities of the several fractions of 80% ethanol extracts of AP significantly increased by EtOAC and BuOH fractions. Thus, the present study suggests that the response of a component of the BuOH fraction to NO generation via iNOS expression provide an important clue to elucidate anti-inflammatory mechanism of AP.

• Advances in Traditional Medicine
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• v.9 no.3
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• pp.238-244
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• 2009

Gymnosporia rothiana (walp) Lawson (celastraceae), commonly known as Maytenus rothiana, is used in Indian folk medicine as an antiulcerogenic agent. However, there have been no scientific reports regarding its antiulcer activity. Therefore, this study was intended to evaluate the antiulcer property of petroleum ether, chloroform, and methanolic extract of leaves of Gymnosporia rothiana at different dose levels in ethanol induced and indomethacin induced gastric ulcer models. It was observed that oral administration of all the extract of Gymnosporia rothiana produces significant reduction in ulcer lesion index as well as increase in volume and pH of gastric content in both experimental models, being petroleum ether extract the most effective at dose of 250 mg/kg; it significantly reduced gastric lesion index (70.06%), in comparison to omeprazole (71.20%) and methanolic extract at a dose of 500 mg/kg (67.22%). Increased gastric mucosal defense mechanism by petroleum ether extract is probably due to its high levels of terpenoids like $\beta$ amyrin, lupeol acetate. The present results clearly shows antiulcer effect of Gymnosporia rothiana against various irritants has been mainly due to cytoprotective effect mediated through prostaglandin and partly due to free radical scavenging activity.