• Title/Summary/Keyword: $NO_2$ inhibition

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Anti-inflammatory Effects of Smilacis Glabrae Rhizoma in Raw 264.7 Cells (토복령(土茯笭)의 Raw 264.7 세포에 대한 항염효과)

  • Oh, Sung-Won;Kim, Byoung-Woo
    • The Journal of Internal Korean Medicine
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    • v.30 no.2
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    • pp.288-297
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    • 2009
  • Objective : Inflammatory cytokines have a close relationship to insulin dependent diabetes mellitus (IDDM). The inhibitory effect of Smilacis Glabrae Rhizoma (SGR) were examined on production of nitric oxide (NO), prostaglandin $E_2$ $(PGE_2)$, synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and NF-${\kappa}$B activation in Raw 264.7 cells. Methods: Raw 264.7 cells were pretreated with SGR(20, 50, 100 ${\mu}g$/ml), and then cultured with lipopolysaccharides (LPS). Cell viability was measured by MTT assay; inhibition of NO, $PGE_2$, and TNF-${\alpha}$ production were measured by Griess reagent and enzyme-linked immunosorbent assay(ELISA). Induction of COX-2 and iNOS were determined by western blotting analysis. Inhibition of NF-${\kappa}$B was measured by immunofluorescence assay (IFA). Results: SGR inactivated NF-${\kappa}$B, and inhibited the production of NO, iNOS, and $PGE_2$. Inhibition of COX-2 and TNF-${\alpha}$ could not be confirmed. Conclusions: From the above result. SGR was found to have an anti-inflammatory effect of inhibition of NO, iNOS, and $PGE_2$ production via inhibition of NF-${\kappa}$B.

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Feasible monitoring of the inhibitory effects of free NH3 on NO2- oxidation

  • Yoo, Byeong-Hak;Lee, Sang-hun
    • Geosystem Engineering
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    • v.21 no.5
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    • pp.243-250
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    • 2018
  • This study investigated nitrite ($NO_2{^-}$) accumulation due to FA (Free Ammonia: $NH_3$) inhibition in an anaerobic-aerobic-anoxic (AOA) process reactor to mainly treat wastewater containing 302-610 mg/L of $NH_3/NH_4{^+}-N$. Based on an experimental operation focusing on the nitrification, it was observed that $NO_2{^-}$ was accumulated in the aerobic nitrification zone as pH increased, due to inhibition of $NO_2{^-}$ conversion to $NO_3{^-}$ by FA. This result implied FA inhibition to NOB ($NO_2{^-}$-Oxidizing Bacteria) for converting $NO_2{^-}$ to $NO_3{^-}$. The objective of this study is to develop a feasible monitoring procedure for early detection of the FA inhibition toward $NO_2{^-}$ accumulation and poor nitrification. Thus, in order to rapidly assess FA concentrations, an $NH_3$ probe was utilized to measure $NH_3$ concentrations together with applying a simple model prediction using the measured $NH_4{^+}$ concentrations, the Henry's law constant of $NH_3$ and measured pH. The predictive model $NH_3$ levels were verified by a good correlation (89%) with the corresponding measured data, but the model prediction underestimated FA concentrations at less than 7.4 and a little overestimated at pH above 7.5. Interestingly, accumulated $NO_2{^-}$ levels were roughly correlated with FA levels that were observed at delayed time points. This reflects the detected FA levels can be good indicators of $NO_2{^-}$ levels with some delayed time. $NO_2{^-}$ accumulation started at measured FA concentrations of higher than approximately 3 mg/L and ceased below that FA level.

Inhibition of Nitric Oxide Synthesis by Methanol and Butanol Extracts of Euonymus Alatus (Thunb.) Sieb in Murine Macrophages

  • Lee Hyo-Hyun;Park Young-Soo;Kim Ra-Young;Kim Dong-Il;Lee Tae-Kyun
    • The Journal of Korean Medicine
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    • v.26 no.1 s.61
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    • pp.26-36
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    • 2005
  • Objective : Many traditional herbal remedies exhibit several beneficial effects including anti-inflammation. Euonymus alatus (Thunb.) Sieb (EA), known as Gui jun woo in Korea, has long been used in folk medicine to regulate Qi (bodily energy) and blood circulation, relieve pain, eliminate stagnant blood, and treat dysmenorrhea in oriental countries. The exact mechanism of the anti-inflammatory action of Euonymus alatus (Thunb.) Sieb (EA), however, has not been determined. Methods: Since there is increasing evidence that nitric oxide (NO) plays a crucial role in the pathogenesis of inflammatory diseases, this study was undertaken to address whether the methanol (MeOH) extract and its fractions of the bark of EA could modulate the expression of inducible NO synthase (iNOS) in thioglycollate-elicited murine peritoneal macrophages and murine macrophage cell line, RA W264.7 cells. Results: Stimulation of the peritoneal macrophages and RAW264.7 cells with $interferon-\gamma\;(IFN-\gamma)$ and lipopolysaccharide (LPS) resulted in increased production of NO in the medium. However, the butanol (BuOH) fraction of the MeOH extract of EA barks showed marked inhibition of NO synthesis in a dose-dependent manner. The inhibition of NO synthesis was reflected in the decreased amount of iNOS protein, as determined by Western blotting. The BuOH fraction did not affect the viability of RA W264.7 cells, as assessed by methylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide (MTT) assay; rather, it reduced endogenous NO-induced apoptotic cell death via inhibition of NO synthesis in RAW264.7 cells. On the other hand, the MeOH and BuOH fraction showed no inhibitory effect on the synthesis of NO by RAW264.7 cells, when iNOS was already expressed by the stimulation with $IFN-\gamma$ and LPS. Conclusion: Collectively, these results demonstrate that the MeOH and BuOH fraction inhibits NO synthesis by inhibition of the induction of iNOS in murine macrophages.

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Effect of Inhibitors on cell growth and urease activity of Vibrio parahaemolyticus (저해제가 Vibrio parahzemolyticius 균주의 생육 및 요소분해효소의 활성에 미치는 영향)

  • 김종숙;김영희
    • Journal of Life Science
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    • v.10 no.6
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    • pp.558-563
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    • 2000
  • Effect of inhibitors on Vibrio parahaemolyticus cell growth and its urease activity was studied. The growth of the bacterium and the enzyme activity were inhibited by the addition of 0.02% p-hydroxymercuric benzoate, $HgCl_2$and $AgNO_3$. However, same concentration of boric acid, thallium acetate and $Pb(NO_3)_2$ did not affect the cell growth but inhibited urease activity by 25%, 29%, and 38%, respectively. Acetohydroxamic acid was the most potent inhibitor on cell growth by inhibiting 40% but did not affect urease activity. To investigate the effect of inhibitors on urease activity, urease was purified and confirmed on SDS-PAGE. The purified urease was inhibited 100% by the addition of 1 mM acetohydroxamic acid and $AgNO_3$but no inhibition was occurred by the addition of the same concentration of thallium acetate. and the addition of 0.01 mM of $HgCl_2$ and acetohydroxamic acid inhibited the purified urease activity by 39% and 24%, respectively. On 0.1 millimolar basic, acetohydroxamic acid and $HgCl_2$inhibited 4 times more active in urease inhibition than p-hydroxymercuric benzoate whereas no inhibition was occurred either thallium acetate or $Pb(NO_3)_2$.

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Bioassay-Guided Isolation and Identification of Compounds from Arecae Pericarpium with Anti-inflammatory, Anti-oxidative, and Melanogenesis Inhibition Activities

  • Indriana, Amelia;Lee, Kyoung Jin;Kim, Yeong Shik
    • Natural Product Sciences
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    • v.22 no.3
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    • pp.193-200
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    • 2016
  • This study describes the anti-inflammatory, anti-oxidant, and melanogenesis inhibition activities of methanol extract and various organic solvent fractions of Arecae Pericarpium. We examined the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells, 1,1-diphenyl-2-picrylhydrazine (DPPH) scavenging activity, mushroom tyrosinase inhibition activity and melanin contents. The study showed that, among all tested fractions, methylene chloride fraction showed the strongest inhibition of LPS-induced NO production in RAW 264.7 cells ($IC_{50}$ value $8.89{\mu}g/mL$) and DPPH radical scavenging activity ($EC_{50}$ value $21.39{\mu}g/mL$). Methylene chloride and ethyl acetate fractions similarly inhibited mushroom tyrosinase activity. Methanol extract exhibited strongest reduction of melanin content in B16F10 melanoma cells. Based on the bioactivity assay results, methylene chloride and ethyl acetate fractions were further separated. Eight phenolic compounds were isolated, which are dimeric syringol (1), catechol (2), 4-hydroxybenzaldehyde (3), vanillin (4), 4-hydroxyacetophenone (5), apocynin (6), protocatechuic acid (7) and 4-hydroxybenzoic acid (8). Among the isolated compounds tested, catechol showed the strongest inhibition of LPS-induced NO production in RAW 264.7 cells. Catechol also showed the concentration-dependent NF-${\kappa}B$ inhibition activity. Arecae Pericarpium might have potentials to be developed as anti-inflammatory agent or dermatological product for skin-whitening agent.

Cognitive and Emotional Inhibition Processes of Gifted Children: Word-color and Emotional Stroop Effects (영재 아동들의 인지 및 정서적 억제처리 과정: 스트룹 효과 및 정서 스트룹 효과 중심으로)

  • Nam, Sooleen;Nam, Kichun;Baik, Yeonji
    • Journal of Gifted/Talented Education
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    • v.25 no.4
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    • pp.469-491
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    • 2015
  • The present study investigated the inhibition mechanisms of gifted children, which is one of the main executive functions in human cognitive system. The inhibition process was subdivided into cognitive and emotion aspects in order to examine the interplay between these two aspects with respect to inhibition processing. In Experiment 1, word-color Stroop task was used to study the cognitive inhibition process of 100 gifted children(Gender: 62 males, 38 females; Academic grade: 46 Elementary school students, 54 Secondary school students). In addition, emotional Stroop task was utilized in Experiment 2 to examine the effect of emotional component during cognitive inhibition process. Results revealed a significant cognitive cost (i.e., word-color Stroop effect) when participants had to withhold automatic response during cognitive inhibition task in Experiment 1. Such cognitive cost was reduced as the chronological age of the participants increased, with no difference in gender. The results in Experiment 2 showed no significant emotional inhibition cost (i.e., emotional Stroop effect) during cognitive inhibition task, and there was no effect of gender nor age. This suggests that the emotional component conveyed in words did not lead to cognitive bias effects. This study proposes that the cognitive and emotional inhibition processes are seemingly independent mechanisms that engage in complex interactions during inhibition processing of behavioral response.

Analysis of Free Ammonia Inhibition of Nitrite Oxidizing Bacteria Using a Dissolved Oxygen Respirometer

  • Kim, Dong-Jin;Lee, Dong-Ig;Cha, Gi-Cheol;Keller, Jurg
    • Environmental Engineering Research
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    • v.13 no.3
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    • pp.125-130
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    • 2008
  • Free ammonia ($NH_3$-N) inhibition of nitrite-oxidizing bacteria (NOB) has been widely studied for partial nitrification (or nitrite accumulation) and denitrification via nitrite ($NO_2^-$-N) as a low-cost treatment of ammonium containing wastewater. The literature on $NH_3$-N inhibition of NOB, however, shows disagreement about the threshold $NH_3$-N concentration and its degree of inhibition. In order to clarify the confusion, a simple and cheap respirometric method was devised to investigate the effect of free ammonia inhibition of NOB. Sludge samples from an autotrophic nitrifying reactor were exposed to various $NH_3$-N concentrations to measure the maximum specific nitrite oxidation rate ($\hat{K}_{NO}$) using a respirometer. NOB biomass was estimated from the yield values in the literature. Free ammonia inhibition of nitrite oxidizing bacteria was reversible and the specific nitrite oxidation rate ($K_{NO}$) decreased from 0.141 to 0.116, 0.100, 0.097 and 0.081 mg $NO_2^-$-N/mg NOB h, respectively, as the $NH_3$-N concentration increased from 0.0 to 1.0, 4.1, 9.7 and 22.9 mg/L. A nonlinear regression based on the noncompetitive inhibition mode gave an estimate of the Inhibition concentration ($K_I$) of free ammonia to be 21.3 mg $NH_3$-N/L. Previous studies gave $\hat{K}_{NO}$ of Nitrobacter and Nitrospira as 0.120 and 0.032 mg/mg VSS h. The free ammonia concentration which inhibits Nitrobacter was $30{\sim}50\;mg$ $NH_3$-N/L and Nitrospira was inhibited at $0.04{\sim}0.08\;mg$ $NH_3$-N/L. The results support the fact that Nitrobacter is the dominant NOB in the reactor. The variations in the reported values of free ammonia inhibition may be due to the different species of nitrite oxidizers present in the reactors. The respirometric method provides rapid and reliable analysis of the behavior and community of the nitrite oxidizing bacteria.

Study on Physiologically Active Compounds and Antioxidant Activity of Korean Yam (Dioscorea batatas DECNE.)

  • Duan, Yishan;Kim, Gyeong-Hwuii;Kim, Han-Soo
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.2
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    • pp.342-351
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    • 2016
  • The bioactive compound and antioxidant property of Korean yam (Dioscorea batatas DECNE.) were studied using in vitro methods. Yam available in Korea was analyzed for lycopene, chlorophyll a, b, tannin, phytic acid and total saponin contents. 70% Methanol, 70% ethanol and chloroform-methanol mixture (CM, 2:1, v/v) were used to extract yam. Then the antioxidant activity evaluated through ferrous ion chelating activity, ${\beta}$-carotene bleaching method, lipid peroxidation inhibition and nitric oxide (NO) radical scavenging activity. 70% Methanol extract showed the highest ferrous ion chelating activity and NO radical scavenging activity. And CM extract was the most effective in inhibition of linoleic acid peroxidation evaluated by ${\beta}$-carotene bleaching assay and lipid peroxidation inhibition assay. Based on the results obtained, yam is a potential active ingredient that could be applied in antioxidation as well as bio-health functional food to take a good part in prevention of human diseases and aging.

Evaluation of Antioxidative activity of Korean Yam (Dioscorea batatas DECNE.) by n-Butanol and Ethyl Acetate Extracts

  • Duan, Yishan;Kim, Han-Soo;Kim, Gyeong-Hwuii
    • Journal of the Korean Applied Science and Technology
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    • v.32 no.2
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    • pp.312-319
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    • 2015
  • In this study, n-butanol and ethyl acetate extracts were prepared from raw yam (Dioscorea batatas DECNE.). Their antioxidative potencies were investigated employing various in vitro methods, such as ferrous ion chelating, ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and nitric oxide (NO) radical scavenging and nitrite scavenging activity. The n-butanol fraction was assayed to possess stronger antioxidant activity by ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and NO radical scavenging activity. However, ethyl acetate extract was more effective in chelating ferrous ion and scavenging nitrite. Based on the results obtained, yam is a potential active ingredient that could be applied in antioxidation as well as bio-health functional food to take a good part in prevention of human diseases and aging.

Dose Motor Inhibition Response Training Using Stop-signal Paradigm Influence Execution and Stop Performance?

  • Son, Sung Min
    • The Journal of Korean Physical Therapy
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    • v.32 no.2
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    • pp.70-74
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    • 2020
  • Purpose: This study examined whether 1) the motor inhibition response as cognitive-behavioral component is learning though a stop signal task using stop-signal paradigm, and 2) whether there is a difference in the learning degree according to imagery training and actual practice training. Methods: Twenty young adults (males: 9, females: 11) volunteered to participate in this study, and were divided randomly into motor imagery training (IT, n=10) and practice training (PT, n=10) groups. The PT group performed an actual practice stop-signal task, while the IT group performed imagery training, which showed a stop-signal task on a monitor of a personal computer. The non-signal reaction time and stop-signal reaction time of both groups were assessed during the stop-signal task. Results: In the non-signal reaction time, there were no significant intra-group and inter-group differences between pre- and post-intervention in both groups (p>0.05). The stop-signal reaction time showed a significant difference in the PT group in the intra-group analysis (p<0.05). On the other hand, there was no significant intra-group difference in the IT group and inter-group difference between pre- and post-intervention (p>0.05). Conclusion: These results showed that the motor inhibition response could be learned through a stop-signal task. Moreover, these findings suggest that actual practice is a more effective method for learning the motor inhibition response.