• Journal of Pharmacopuncture
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• v.12 no.4
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• pp.89-96
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• 2009

Objectives : The purpose of this study is to investigate the effect of Water Extract from Lactobacillus pentosus-fermented ARTEMISIAE ARGI FOLIUM (AFL) on nitric oxide production of mouse macrophage Raw 264.7 cells impaired by various toxicants such as gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde. Methods : ARTEMISIAE ARGI FOLIUM was fermented with Lactobacillus pentosus and extracted by water. Nitric oxide production of mouse macrophage Raw 264.7 cells was measured by Griess reagent assay. Examined concentrations of AFL were 10, 50, 100, 200, 400 ug/mL. Results : The results of the experiment are as below. 1. AFL at the concentration of 400 ug/mL significantly recovered nitric oxide production which was reduced by gallic acid (100 uM) in Raw 264.7 cells. 2. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by EtOH (100 uM) in Raw 264.7 cells. 3. AFL at the concentration of 400 ug/mL significantly recovered nitric oxide production which was reduced by nicotine (1mM) in Raw 264.7 cells. 4. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by acetaminophen(2 mM) in Raw 264.7 cells. 5. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by acetaldehyde (200 uM) in Raw 264.7 cells. Conclusions : AFL could be supposed to have the immune-enhancing activity related with nitric oxide production of macrophage impaired by various toxicants.

• Environmental Analysis Health and Toxicology
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• v.15 no.3
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• pp.69-80
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• 2000

ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.249-254
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• 2003

본 연구는 환경호르몬(endocrine disruptors)으로 분류되었으며, 에스트로젠 화합물의 특성을 지닌 4-Nonylphenol (NP)이 설치류 Pituitary 세포 중 성장호르몬을 분비하는 GH3 세포의 Nitric oxide(NO)을 증가시키는 작용기전을 규명코자 수행되었다 먼저 GH3세포에 NP처리 농도에 따른 NO의 생성을 측정한 결과 NP처리농도 의존적으로 증가시켰다. 이러한 NO의 증가가 genomic action인지를 확인하기 위해 GH3세포의 NO를 증가시키는 효소인 neuronal oxide synthase의 단백질량을 측정한 결과 GH3세포에서 NP에 의한 nNOS의 단백질의 변화는 없었다. 에스트로젠 화합물인 NP가 에스트로젠 리셉터 (ER)와의 관계를 조사하기 위해 ER억제제(ICI 168,780)클 처리한 경우 NP에 의해 증가한 NO가 감소하였다. 또한 유전자 전사억제제인 actinomycin D 및 단백질 발현 억제제인 cycloheximide을 처리한 경우는 NP에 의한 NO 증가억제효과가 없었다. 이러한 결과를 종합해 볼 때 GH3 세포에서 NP는 ER을 매개한 non-genomic action에 의해 NO를 증가키는 것으로 사료된다.

• Corrosion Science and Technology
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• v.9 no.1
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• pp.20-28
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• 2010

According to the bipolar model, ion selectivity of some species in the passive film is important factor to control the passivation. An increase of cation selectivity of outer layer of the passive film can stabilize the film and improves the corrosion resistance. Therefore, the formation and roles of ionic species in the passive film should be elucidated. In this work, two types of solution (hydrochloric or sulfuric acid) were used to test high N and Mo-bearing stainless steels. The objective of this work was to investigate the formation of oxyanions in the passive film and the roles of oxyanions in passivation of stainless steel. Nitrogen exists as atomic nitrogen, nitric oxide, nitro-oxyanions (${NO_x}^-$), and N-H species, not nitride in the passive film. Because of its high mobility, the enriched atomic nitrogen can act as a reservoir. The formation of N-H species buffers the film pH and facilitates the formation of oxyanions in the film. ${NO_x}^-$ species improve the cation selectivity of the film, increasing the oxide content and film density. ${NO_x}^-$ acts similar to a strong inhibitor both in the passive film and at active sites. This facilitates the formation of chromium oxide. Also, ${NO_x}^-$ can make more molybdate and nitric oxide by reacting with Mo. The role of Mo addition on the passivation characteristics of stainless steel may differ with the test environment. Mo exists as metallic molybdenum, molybdenum oxide, and molybdate and the latter facilitates the oxide formation. When nitrogen and molybdenum coexist in stainless steel, corrosion resistance in chloride solutions is drastically increased. This synergistic effect of N and Mo in a chloride solution is mainly due to the formation of nitro-oxyanions and molybdate ion. Oxyanions can be formed by a 'solid state reaction' in the passive film, resulting in the formation of more molybdate and nitric oxide. These oxyanions improve the cation selectivity of the outer layer and form more oxide and increase the amount of chromium oxide and the ratio of $Cr_2O_3/Cr(OH)_3$ and make the film stable and dense.

• Journal of Ginseng Research
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• v.37 no.1
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• pp.64-73
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• 2013

Korean red ginseng water extract (KG-WE) has known beneficial effects on the cardiovascular system via inducting nitric oxide (NO) production in endothelium. Endothelial arginase inhibits the activity of endothelial nitric oxide synthase (eNOS) by substrate depletion, thereby reducing NO bioavailability and contributing to vascular diseases including hypertension, aging, and atherosclerosis. In the present study, we demonstrate that KG-WE inhibits arginase activity and negatively regulates NO production and reactive oxygen species generation in endothelium. This is associated with increased dimerization of eNOS without affecting the protein expression levels of either arginase or eNOS. In a vascular tension assay, when aortas isolated from wild type mice were incubated with KG-WE, NO-dependent enhanced vasorelaxation was observed. Furthermore, KG-WE administered via by drinking water to atherogenic model mice being fed high cholesterol diet improved impaired vascular function. Taken together, these results suggest that KG-WE may exert vasoprotective effects through augmentation of NO signaling by inhibiting arginase. Therefore, KG-WE may be useful in the treatment of vascular diseases derived from endothelial dysfunction, such as atherosclerosis.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.24-30
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• 1994

Nitric oxide(NO) synthase was identified and characterized by determining the L-citrulline formed in the NO-Arg pathway in pancreatic tissues. NO synthase activities in chicken pancreas were dependent upon the concentration of L-Arg which is the substrate molecule for the NO synthase, the amount of the enzyme protein used, and linearly on the incubation time. NO synthase in mouse pancreas was found to be constitutive, not induced by lipopolysaccharide treatment. In vitro NO synthase activities of chicken pancreas were inhibited 36%, 21%, 12% and 44% by $200\;{\mu}M$ of MMA, DMA, D'MA and NAME respectively. These results suggest the presence of NO and NO synthase in the pancreas.

• YAKHAK HOEJI
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• v.57 no.6
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• pp.388-393
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• 2013

Previously, we have reported that lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, increased melanin synthesis through intracellular $Ca^{2+}$ release in B16 cells. In this study we investigated the possible involvement of nitric oxide (NO) in the mechanism of lovastatin-induced melanogenesis. Lovastatin elevated NO formation in a dose-dependent manner. Treatment with mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), precursors of cholesterol, did not significantly alter the lovastatin-induced NO production, suggesting that inhibition of cholesterol metabolism may not be involved in the mechanism of this action of lovastatin. Both NO formation and melanogenesis induced by lovastatin was significantly suppressed by treatment with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylinidazoline-1-oxyl-3-oxide (cPTIO), an inhibitor of NO synthase and a NO scavenger, respectively. The lovastatin-induced NO production was significantly affected not by EGTA, an extracellular $Ca^{2+}$ chelator, but by an intracellular $Ca^{2+}$ chelator (BAPTA/AM) and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8). Taken together, these results suggest that lovastatin may induce melanogenesis through NO formation mediated by intracellular $Ca^{2+}$ release in B16 cells. These results further suggest that lovastatin may be a good candidate for the therapeutic application of various hypopigmentation disorders.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.8
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• pp.56-62
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• 1992

This paper is analyzed the charge trapping and electrical properties of 0(Oxide), NO(Nitrided oxide) and ONO(Reoxidized nitrided oxide) as dielectric films in MIS structures. We have processed bottom oxide and top oxide by the thermal method, and nitride(Si$_{3}N_{4}$) by the LPCVD(Low Pressure Chemical Vapor Deposition) method on P-type(100) Silicon wafer. We have studied the charge trapping properties of the dielectrics by using a computer controlled DLTS system. All of the dielectric films are shown peak nearly at 300K. Those are bulk traps. Many trap densities which is detected in NO films, but traps. Many trap densities which is detected in NO films. Varing the nitride thickness, the trap densities of thinner nitride is decreased than the thicker nitride. Finally we have found that trap densities of ONO films is affected by nitride thickness.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.481-484
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• 1998

In activated macrophages the inducible form of nitric oxide synthase (i-NOS) generates high amounts of toxic mediator, nitric oxide (NO) which contributes to the circulatory failure associated with septic shock. A sesquiterpene lactone compound (yomogin) isolated from medicinal plant Artemisia princeps Pampan inhibited the production of NO in LPS-activated RAW 264.7 cells by suppressing i-NOS enzyme expression. Thus, yomogin may be a useful candidate for the development of new drugs to treat endotoxemia and inflammation accompanied by the overproduction of NO.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.50-50
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• 2003

Nitric oxide (NO) has been studied and found to be an important intracellular modulator. The excess NO produced by the inducible nitric-oxide synthase (iNOS) is implicated in various inflammatory diseases and cellular injury. Inflammatory cytokines such as TNF- or IL-6 increase intracellular ceramide and ceramide may induce NO production and inflammation. (omitted)