• 제목/요약/키워드: Nitric oxide (No)

검색결과 2,956건 처리시간 0.043초

A study on γ-Al2O3 Catalyst for N2O Decomposition (N2O 분해를 위한 γ-Al2O3 촉매에 관한 연구)

  • Eun-Han Lee;Tae-Woo Kim;Segi Byun;Doo-Won Seo;Hyo-Jung Hwang;Jueun Baek;Eui-Soon Jeong;Hansung Kim;Shin-Kun Ryi
    • Clean Technology
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    • 제29권2호
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    • pp.126-134
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    • 2023
  • Direct catalytic decomposition is a promising method for controlling the emission of nitrous oxide (N2O) from the semiconductor and display industries. In this study, a γ-Al2O3 catalyst was developed to reduce N2O emissions by a catalytic decomposition reaction. The γ-Al2O3 catalyst was prepared by an extrusion method using boehmite powder, and a N2O decomposition test was performed using a catalyst reactor that was approximately 25.4 mm (1 in) in diameter packed with approximately 5 mm of catalysts. The N2O decomposition tests were carried out with approximately 1% N2O at 550 to 750 ℃, an ambient pressure, and a GHSV=1800-2000 h-1. To confirm the N2O decomposition properties and the effect of O2 and steam on the N2O decomposition, nitrogen, air, and air and steam were used as atmospheric gases. The catalytic decomposition tests showed that the 1% N2O had almost completely disappeared at 700 ℃ in an N2 atmosphere. However, air and steam decreased the conversion rate drastically. The long term stability test carried out under an N2 atmosphere at 700 ℃ for 350 h showed that the N2O conversion rate remained very stable, confirming no catalytic activity changes. From the results of the N2O decomposition tests and long-term stability test, it is expected that the prepared γ-Al2O3 catalyst can be used to reduce N2O emissions from several industries including the semiconductor, display, and nitric acid manufacturing industry.

Inhibition of Inflammation by Popillia flavosellata Ethanol Extract in LPSinduced RAW264.7 Macrophages (LPS로 염증 유도된 RAW 264.7세포에 대한 참콩풍뎅이(Popillia flavosellata) 에탄올 추출물의 항염증 효과)

  • Yoon, Young-Il;Hwang, Jae-Sam;Kim, Mi-Ae;Ahn, Mi Young;Lee, Young-Bo;Han, Myung Sae;Goo, Tae-Won;Yun, Eun-Young
    • Journal of Life Science
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    • 제25권9호
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    • pp.993-999
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    • 2015
  • The beetle Popillia flavosellata has been no reported its functional effects. In this study, we investigated the anti-inflammatory effect of P. flavosellata ethanol extract (PFE) on RAW 264.7 mouse macrophage cells treated with lipopolysaccharide (LPS) for the induction of inflammation. First, we examined the cytotoxicity of PFE in the RAW 264.7 cells at a concentration of 2,000 μg/ml or less. To evaluate the anti-inflammatory effects of PFE, we investigated the expression levels of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6, and proinflammatory enzymes, such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-induced RAW 264.7 cells. In addition, we examined whether PFE inhibited the translocation of nuclear factor kappa B (NF-κB) p65 into the nucleus in the LPS-induced RAW 264.7 cells. We found that the protein levels of TNF-α and IL-6 were decreased in the LPS-induced RAW 264.7 cells after the treatment with PFE in a dose-dependent manner. In addition, we confirmed that PFE inhibited the translocation of NF-κB p65 into the nucleus, as well as the protein expression levels of iNOS and COX-2. Accordingly, we propose that PFE exerts an anti-inflammatory effect through the down-regulation of NF-κB p65, TNF-α, IL-6, iNOS, and COX-2 via the toll like receptor (TLR)-4 inflammatory signaling pathway.

Anti-inflammatory Effect of Flavonoids Kaempferol and Biochanin A-enriched Extract of Barnyard Millet (Echinochloa crus-galli var. frumentacea) Grains in LPS-stimulated RAW264.7 Cells (마우스 대식 세포주 RAW264.7에 있어서 LPS처리에 의해 유도되는 염증반응에 대한 식용피(Echinochloa crus-galli var. frumentacea)의 저해효과)

  • Lee, Ji Young;Jun, Do Youn;Yoon, Young Ho;Ko, Jee Youn;Woo, Koan Sik;Woo, Mi Hee;Kim, Young Ho
    • Journal of Life Science
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    • 제24권11호
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    • pp.1157-1167
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    • 2014
  • In order to compare the anti-inflammatory effects of five selected cereal grains-proso millet, hwanggeumchal sorghum, foxtail millet, barnyard millet, and adlay-the inhibitory activities of 80% ethanol (EtOH) extracts obtained from the individual grains on lipopolysaccharide (LPS)-induced nitric oxide (NO) generation were investigated in RAW264.7 cells. The EtOH extract of barnyard millet (Echinochloa crus-galli var. frumentacea) grains exhibited more potent anti-inflammatory activity than that of the other grains. When the EtOH extract of barnyard millet grains was sequentially fractionated with n-hexane, methylene chloride (MC), ethyl acetate (EtOAc), and n-butanol, the majority of the anti-inflammatory activity was detected in the MC fraction, followed by the EtOAc fraction. Pretreatment with the MC fraction caused downregulation of the expression levels of iNOS- and COX-2-specific transcripts and proteins, as well as proinflammatory cytokine gene transcripts (IL-$1{\beta}$, IL-6, and TNF-${\alpha}$) in LPS-stimulated RAW264.7 cells. Additionally, the MC fraction could suppress not only the LPS-induced nuclear translocation of cytosolic NF-kB, but also the LPS-induced activation of MAPKs, such as ERK, JNK, and p38MAPK. Further analysis of the MC fraction by HPLC identified kaempferol, biochanin A, and formononetin as the major phenolic components. Both kaempferol and biochanin A, but not formononetin, could exert anti-inflammatory effect at the same concentrations as those of the MC fraction. Consequently, these results indicate that kaempferol and biochanin A are among the most effective anti-inflammatory phenolic components in barnyard millet grains. This finding suggests that barnyard millet grains and the MC extract enriched in kaempferol and biochanin A could be beneficial functional food sources that have an anti-inflammatory effect.

Biological Activities of Hot Water Extracts from Euonymus alatus Leaf (화살나무 잎 열수추출물의 생리활성)

  • Kwon, Gu-Joong;Choi, Dae-Sung;Wang, Myeong-Hyeon
    • Korean Journal of Food Science and Technology
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    • 제39권5호
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    • pp.569-574
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    • 2007
  • This study was performed to investigate the biological activities of roasted (RE) and non-roasted (NRE) hot water extract samples from Euonymus alatus leaf by measuring DPPH radical scavenging, total polyphenol content, hydroxyl radical scavenging, superoxide dismutase (SOD)-like activity, anti-inflammatory activity, and inhibitory effects on ${\alpha}-amylase$ and ${\alpha}-glucosidase$ in vitro. The $IC_{50}$ values fur DPPH free radical scavenging activity of the NRE and RE hot water extracts were $19.1{\mu}g/mL$ and $21.9{\mu}g/mL$, respectively, and their total polyphenol contents were estimated as 9.6 mg/g for NRE and 10.6 mg/g for RE. Both NRE and RE scavenged the hydroxyl radical in a concentration-dependent manner, but their activities were lower than that of BHA. It was also shown that SOD-like activity was dependent on NRE and RE concentration, and the SOD-like activity of NRE was slightly higher than that of RE. The highest SOD-like activity obtained from NRE was 20% at a concentration of 3 mg/mL. Neither NRE nor RE seemed to have an effect on ${\alpha}-amylase$ and ${\alpha}-glucosidase$ inhibition. Finally, the hot water extracts of NRE and RE significantly decreased the concentration of LPS-induced NO in RAW 264.7 cells, indicating anti-inflammatory activity.

Clinical Features of Symptomatic Neonates with Ebstein's Anomaly (신생아기에 증상을 나타낸 엡슈타인 기형의 임상양상)

  • Cho, Hee Jin;Lee, In Sil;Ko, Jae Kon
    • Clinical and Experimental Pediatrics
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    • 제48권11호
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    • pp.1212-1218
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    • 2005
  • Purpose : Forward pulmonary blood flow may be absent in some neonates with Ebstein's anomaly by anatomical or functional pulmonary atresia in association with the elevated pulmonary vascular resistance, patent ductus arteriosus and tricuspid regurgitation. We reviewed the presentation and outcomes of symptomatic neonates with Ebstein's anomaly focusing on the pulmonary atresia. Methods : Clinical presentation and outcome of 15 symptomatic neonates with Ebstein's anomaly seen at Asan medical center from 1998 to 2004 were reviewed. Results : Ten(67%) of 15 patients showed no forward pulmonary blood flow and 6 of them had functional pulmonary atresia. $O_2$ saturation and pH were lower and cardiothoracic(CT) ratio in chest radiography was more increased in the patients with pulmonary atresia than in the patients without pulmonary atresia(P<0.05). pH and CT ratio were not different between the anatomical and functional pulmonary atresia group, but $O_2$ saturation was lower in functional atresia group(P<0.05). 13 patients(87%) were managed with $PGE_1$. 4 of 6 patients with functional pulmonary atresia were treated with inhaled nitric oxide. Surgery was performed in 1 of 5 patients without pulmonary atresia and in 8 of 10 patients with pulmonary atresia during follow-up period(mean 37 months). 3 patients(20%) died and none of patients without pulmonary atresia died. Conclusion : We found that most symptomatic neonates with Ebstein's anomaly had functional or anatomical pulmonary atresia. The neonates with Ebstein's anomaly who had no forward pulmonary blood flow were more symptomatic and needed surgery earlier. Further studies will be needed to distinguish effectively functional and anatomical pulmonary atresia and to manage appropriately neonates with functional atresia.

Anti-Oxidant, Anti-Melanogenic, and Anti-Inflammatory Activities of Zanthoxylum schinifolium Extract and its Solvent Fractions (산초 추출물 및 분획물의 항산화, 미백 및 항염증 활성)

  • Jin, Kyong-Suk;Oh, You Na;Park, Jung Ae;Lee, Ji Young;Jin, Soojung;Hyun, Sook Kyung;Hwang, Hye Jin;Kwon, Hyun Ju;Kim, Byung Woo
    • Microbiology and Biotechnology Letters
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    • 제40권4호
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    • pp.371-379
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    • 2012
  • This study was designed to explore new nutraceutical and cosmetic resources possessing biological activities from the plant kingdom. To fulfill this purpose, we analyzed the anti-oxidative, anti-melanogenic, and anti-inflammatory activities of Zanthoxylum schinifolium extract (ZSE) and its solvent fractions using in vitro assays and cell culture model systems. Three kinds of ZSE treated with methanol, ethanol, and water exhibited potent anti-oxidative activities through DPPH radical scavenging capacity, and inhibited in vitro DOPA oxidation. Furthermore, Z. schinifolium methanol extract (ZSME) inhibited the ${\alpha}$-melanocyte stimulating hormone, which induces melanin contents in B16F10 cells. Its anti-melanogenic activity originates from the inhibition of tyrosinase enzyme activity and melanogenesis related protein expression. Moreover, lipopolysaccharide induced nitric oxide production in the RAW 264.7 cell line was also ameliorated by ZSME treatment in a dose dependent manner. Among the four solvent fractions of ZSME treated with dichloromethane, ethyl acetate, n-butanol, and water, three fractions, except water, showed significant anti-melanogenic and anti-inflammatory activities. Taken together, these results provide important new insights into Z. schinifolium, indicating that it possesses numerous biological activities such as anti-oxidative, anti-melanogenic, and anti-inflammatory activities. Therefore, it may well serve as a promising material in the field of nutraceuticals and cosmetics.

Role of NO in Activation of $NF{\kappa}B$ by PM2.5 in Lung Epithelial Cells (PM2.5로 자극한 폐상피세포의 $NF{\kappa}B$ 활성화에 NO의 역할)

  • Kim, Kyoung-Ah;Nam, Hae-Yun;Mun, Je-Hyeok;Jeong, Jin-Sook;Lim, Young;Kai, Hirofumi
    • Tuberculosis and Respiratory Diseases
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    • 제52권6호
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    • pp.616-626
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    • 2002
  • Background : The present study was performed to further improve our understanding of molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the lung, by particulate matter in lung epithelial cells with an aerodynamic diameter of less than $2.5{\mu}m$(PM2.5). Materials and Methods : Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), $I{\kappa}B$ degradation and $NF{\kappa}B$-dependent transcriptional activity, in 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM2.5-induced $NF{\kappa}B$ activation in A549 cells. Results : The rapid degradation of $I{\kappa}B$ and the increase of transcriptional activity of the $NF{\kappa}B$-dependent promotor were observed in A549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A549 cells was not clearly detected, although immediate responses were observed in RAW264.7 cells. A 549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced $I{\kappa}B$ degradation and the increase of the $NF{\kappa}B$-dependent transcriptional activity. Conclusion : These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of $NF{\kappa}B$ in the pulmonary epithelium.

Anti-inflammatory Activity of Extracts of Hovenia dulcis on Lipopolysaccharides-stimulated RAW264.7 Cells (LPS로 유도된 RAW264.7 대식세포에 대한 헛개나무(Hovenia dulcis) 추출물의 항염증 효과)

  • Woo, Hyun Sim;Lee, Sun Min;Heo, Jeong Doo;Lee, Min-Sung;Kim, Yeong-Su;Kim, Dae Wook
    • Korean Journal of Plant Resources
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    • 제31권5호
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    • pp.466-477
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    • 2018
  • In this study, the anti-inflammatory activities of the extracts of different parts of Hovenia dulcis such as leaves, stems, and roots were investigated. Among them, the roots extract (RE) showed the most potent suppressive effect against pro-inflammatory mediators in LPS-stimulated mouse macrophage cells. RE induced dose-dependent reduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and concomitantly reduced the production of NO and $PGE_2$. Additionally, pre-treatment with RE significantly suppressed the production of inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6, as well as mRNA levels. Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-kB) were also strongly attenuated by RE in RAW264.7 cell. Furthermore, RE induced HO-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and increase HO-1 activity in RAW264.7 macrophages. Therefore, these results indicate that RE strongly inhibits LPS-induced inflammatory responses by blocking NF-kB activation, inhibiting MAPKs phosphorylation, and enhancing HO-1 expression in macrophages, suggesting that RE of H. dulicis and a major component, 27-O-protocatechuoylbetulinic acid could be applied as a valuable natural anti-inflammatory material.

Enhancement of Immune Activities of Peptides from Asterias amurensis Using a Nano-encapsulation Process (나노 입자 불가사리 펩타이드의 면역 활성 증진)

  • Jeong, Hyang-Suk;Oh, Sung-Ho;Kim, Seoung-Seop;Jeong, Myoung-Hoon;Choi, Woon-Yong;Seo, Yong-Chang;Choi, Geun-Pyo;Kim, Jin-Chul;Lee, Hyeon-Yong
    • Korean Journal of Food Science and Technology
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    • 제42권4호
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    • pp.424-430
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    • 2010
  • Immuno-modulatory activities of peptides from Asterias amurensis were investigated using a nano-encapsulation process. The molecular weights of the peptides in the range of 5-7 kDa were separated using Sephadex G-75 gel filtration. Eighty-five percent of the nano-particles were in the 300 nm range using dynamic light scattering. The cytotoxicity of the A. amurensis nano-particles against CCD-986sk human dermal fibroblast cells was 11.64% after adding 1.0 mg/mL of the samples, which was lower than that from the control (13.28% collagen). The secretion of $NO^-$ from macrophages was estimated as $40\;{\mu}M$ after adding 1.0 mg/mL of gelatin nano-particles, which was higher than the others. Prostaglandin $E_2$ production from UV-induced human skin cells decreased greatly to 860 pg/mL after adding 1.0 mg/mL of the samples. Confocal microscopy revealed that nano-particles effectively penetrated the cells within 1 hour. From these results, we consider that nano-encapsulation of the peptides from A. amurensis can improve their biological functions.

Enhancement of Skin Immune Activation Effect of Collagen Peptides Isolated from Asterias amurensis (불가사리 유래 콜라겐 펩타이드의 피부 면역 증진 효과)

  • Jeong, Hyang-Suk;Kwon, Min-Chul;Han, Jae-Gun;Ha, Ji-Hye;Jin, Ling;Kim, Jin-Chul;Kwak, Hyeong-Geun;Hwang, Bo-Young;Lee, Hyeon-Yong
    • Korean Journal of Food Science and Technology
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    • 제40권5호
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    • pp.522-527
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    • 2008
  • Low molecular peptides were isolated from Asterias amurensis via SDS-PAGE. The peptides were separated via consecutive gel filtration as five fractions (F1-F5) according to molecular weights, based on the results of MALDI-TOF MS analysis. The molecular weight of the most active peptide was estimated as 15,000 daltons. The peptide showed cytotoxicity on normal human fibroblast cells at levels as low as 20% when 1.0 mg/mL of the samples was added. The peptide also exhibited higher levels of nitric oxide production from macrophages than the lipopolysaccaharides. It was determined that prostaglendin $E_2$ production was significantly inhibited, up to 127.8% as compared to the control. The low molecular peptide inhibited hyaluronidase activity as 535.7 ${\mu}g/mL$ of $IC_{50}$. It can be concluded that the relatively low molecular weight peptide, fucoidan, from A. amurensis has excellent cosmetic and immunomodulatory activities, which can be considered as a possible resource of new cosmetic agents for skin immunomodulation.