• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.1
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• pp.24-29
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• 2020

In this study, we investigated the inhibition effects of mixtures of Atractylodes macrocephala (AM) and Amomum villosum (AV) water extracts on adipocyte differentiation. Treatment with mixtures of AM and AV extracts in a ratio of 3:1 for 24 and 48 hours did not show any cytotoxicity in OP9 cells. Mixtures of AM(3) and AV(1) extracts inhibited adipocyte differentiation, expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAT/enhancer-binding protein alpha (C/EBPα), the major transcription factors of differentiation. It also inhibited the expression of lipoprotein lipase (LPL), adipocyte protein 2 (aP2), which are PPARγ-target genes in adipocyte. We also checked the inhibition effects on cell proliferation during the early stage of differentiation by treatment with mixtures of AM(3) and AV(1) extracts. It markedly inhibited adipocyte proliferation after 48 hours, and also the phosphorylation of ERK1/2 and Akt after 10 min or 3 hour. These results identify a possible mechanism of action of mixtures of AM(3) and AV(1) extracts, suggesting that the mixtures of AM(3) and AV(1) extracts-induced inhibition of ERK and Akt phosphorylation suppresses adipogenesis by inhibiting other signaling cascades that include PPARγ and C/EBPα during the process of OP9 adipocyte differentiation.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.39-52
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• 1998

HIV-1 tat, a strong transactivator, is essential for the HIV-1 replication and AIDS progression. The Tat function is markedly inhibited by human anti-oncogene p53. This work was initiated to identify the p53-associated inhibitory mechanism on tat-mediated transactivation. Inhibitory function of p53 was confirmed by co-transfection of tat-expressing Jurkat cells with LTR-CAT plasmid, or H3T1 cells (LTR-CAT integrated HeLa cells) with different ratio of pSV-tat/pCDNA-p53 plasmids. Results from the direct protein-protein interaction between soluble p53 and tat, and yeast two-hybrid experiments showed that the co-suppression mechanism is unlikely to be due to the direct interaction. CAT activity was not affected by tat in Jurkat cells which were transfected with p53-promoter-CAT or p53-enhancer-CAT, suggesting that the tat-mediated p53 suppression is not directly associated with p53-promoter. Finally, we have tested protein kinase activity in p53-tranfected Jurkat cells, which might phosphorylate HIV-1 tat, resulting in inhibition of tat function. Some of our data lead us to assume that the p53-mediated tat inhibition is likely to be associated with p53-associated, signaling-mediated phosphorylation of tat, resulting in the dysfunction of tat. This study is now under investigation.

• Biomolecules & Therapeutics
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• v.21 no.1
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• pp.54-59
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• 2013

In this study, we investigated the effect of (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea catechins from green tea leaves, on activities of cyclooxygenase (COX)-1 and thromboxane synthase (TXAS), thromboxane $A_2$ ($TXA_2$) production associated microsomal enzymes. EGCG inhibited COX-1 activity to 96.9%, and TXAS activity to 20% in platelet microsomal fraction having cytochrome c reductase (an endoplasmic reticulum marker enzyme) activity and expressing COX-1 (70 kDa) and TXAS (58 kDa) proteins. The inhibitory ratio of COX-1 to TXAS by EGCG was 4.8. These results mean that EGCG has a stronger selectivity in COX-1 inhibition than TXAS inhibition. In special, a nonsteroid anti-inflammatory drug aspirin, a COX-1 inhibitor, inhibited COX-1 activity by 11.3% at the same concentration ($50{\mu}M$) as EGCG that inhibited COX-1 activity to 96.9% as compared with that of control. This suggests that EGCG has a stronger effect than that of aspirin on inhibition of COX-1 activity. Accordingly, we demonstrate that EGCG might be used as a crucial tool for a strong negative regulator of COX-1/$TXA_2$ signaling pathway to inhibit thrombotic disease-associated platelet aggregation.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.21-29
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• 2007

Paeonia lactiflora was stepwise extracted with hexane, chloroform, ethyl acetate, butanol and water. Anti-microbial activity of each extract was investigated. Methanol extract of P. lactiflora revealed anti-microbial activity against S. mutans, C. albicans, and S. aureus. Also, hexane fraction revealed anti-bacterial activity against S. mutans and ethyl acetate fraction acted as potent anti-microbial agent on C. albicans and S. aureus. The relative growth ratio(RGR) of hexane fraction of P. lactiflora against S. mutans were determined as 77.8% in concentration of 0.125 mg/ml, 98.46% in 0.25 mg/ml and 100% in 0.5 mg/ml. The ethyl acetate fraction of P. lactiflora revealed RGR against C. albicans as 52.5% in concentration of 0.125 mg/ml, 60.83% in 0.25 mg/ml and 78.33% in 0.5 mg/ml. It indicate that increasing concentration increase RGR. The measured minimal inhibitory concentration(MIC) of hexane fraction on S. mutans KCTC 5316 strain was 0.5 mg/ml and MIC of ethyl acetate fraction on C. albicans KCTC 7270 was 2.0 mg/ml. The experiment of inhibition to growth of KB roll(oral squamous cell carcinoma) result 61.9% in butanol, 76.7% in hexane extract of P. lactiflora. The hexane extract exhibit potent inhibition effect to the growth of KB cell. These results suggest that the hexane extract of Paeonia lactiflora has antimicrobial activity against S. mutans and has preventive effect to dental caries in addition to potent inhibition to KB cell growth.

• Bulletin of the Korean Chemical Society
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• v.11 no.5
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• pp.391-395
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• 1990

The kinetics of thermnal cis-trans isomerization reaction of 1-bromopropene(1-BP) was studied at temperatures from 620.8 to 753.15 K over the pressure range 0.17-50.3 Torr. Both the inhibition effect by cyclohexene or propene and the catalytic effect by HBr showed a radical process as the main mechanism of the isomerization. In the suppression of the radical process by the inhibitors, the molecular process also contributed to overall reaction rate. The reactions demonstrated the first order kinetics under both uninhibited and inhibited conditions and could be represented by the expressions (R = 1.987 cal/mol/K) $k_{un}/s^{-1} = (3.45{\pm}1.50){\times}10^{11}$exp$[(- 48100{\pm}2000)/RT]\;k_{ink}/s^{-1} = (2.98{\pm}1.40){\times}10^{12}$exp$[(- 55800{\pm}1800)/RT]$> where $k_{un}$ is the observed rate constant of cis-1-bromopropene(1-B$P_c$) to trans-1-bromopropene(1-B$P_t$) under uninhibited condition at initial pressure of 50 Torr and $k_{ink}$ is the rate constant under maximal inhibition by cyclohexene. The ratio of rate constants for bromine atom elimination from the allylic hydrogen of reactant(1-BP) and from the inhibitors, propene and cyclohexene, were measured from the observed rates of the uninhibited and inhibited reactions. The inhibition efficiencies of cyclohexene and propene were compared kinetically from the rate constants and shown to give good agreement with the previous results reported from other alkyl bromide pyrolyses.

• Korean Journal of Veterinary Research
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• v.63 no.4
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• pp.37.1-37.7
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• 2023

Canine respiratory coronavirus (CRCoV) is a significant pathogen that causes respiratory diseases in dogs, collectively known as a canine infectious respiratory disease. The virus is highly contagious and exhibits high seroprevalence worldwide. Currently, bovine coronavirus (BCoV) enzyme-linked immunosorbent assay (ELISA) kits are used to detect CRCoV antibodies. However, BCoV-ELISA kits cannot differentiate between infections caused by BCoV and those caused by CRCoV. In this study, we evaluated the hemagglutination inhibition (HI) test for CRCoV by comparing it with the virus neutralization (VN) test. Subsequently, we evaluated the seroprevalence of CRCoV in 383 dog serum samples collected from South Korea utilizing the HI test. The HI test for CRCoV showed a strong correlation with the VN test (R = 0.83, p < 0.001). The analysis of seroprevalence revealed that 52.2% (95% confidence interval [CI], 47.2%-57.1%) of the Korean dog serum samples were positive. The seroprevalence exhibited varied with age, with a positivity rate of 43.9% in dogs under 1 year of age and 66.7% in dogs aged 3 to 5 years (odds ratio, 2.54; 95% CI, 1.43-4.59). In conclusion, the HI test to monitor CRCoV antibody proved to be closely related to the VN test. Furthermore, over half of the dogs in Korea tested positive for CRCoV antibodies. These findings contribute to a better understanding of the sero-epidemiology of CRCoV.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.1
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• pp.15-24
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• 2010

Photovoltaic solar cells are all in the incident because they are not converted into electrical energy, high-efficiency solar cells in order to reduce the loss of elements must be. Significant factor in the loss of solar cells, optical loss and electrical loss can be divided into. Optical losses occur when the sun will be joined on the surface of the reflection, the shadow loss due to electrodes, and the losses are in the solar wavelengths. Commercialization is currently the most common solar cells on the front of the light incident on the electrode is formed. Therefore, the shadow caused by the electrode to cover the dead area of the sun, due to factors that hinder the absorption of sunlight which is shadowing them and conversion efficiency of solar cells is the inhibition factor. These barriers to eliminate the electrode linewidth reduces the shadowing to reduce, but simply of the electrode line width is reduced electrode area by reducing the series resistance elevates this because to improve the electrode Aspect ratio(height/width) to increase Ag development of paste is required. In this study, aspect ratio of screen-printing method to increase the electrode Ag paste composition of the binder for the characterization of rheology in the shadow of the electrode by reducing the optical loss of the photoelectric conversion efficiency of solar cells to boost the performance measures was. Properties and printability of the paste, the binder resin sintered characteristics that affect the thermal properties are excellent with a good screen printability acrylic resin, ethyl cellulose, using a resin were evaluated. Prepared paste rheology properties, was formed to evaluate the electrode conductivity and aspect ratio.

• Journal of the Korea Concrete Institute
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• v.26 no.4
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• pp.517-524
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• 2014

Nitrite-Type hydrocalumite (calumite) is a material that can adsorb chloride ions ($Cl^-$) that cause corrosion of reinforce bars and liberate the nitrite ions ($NO_2{^-}$) that inhibit corrosion in reinforced concrete. In this study, polymer-modified mortars using two types of epoxy resin with calumite are prepared with various polymer binder-ratios of 0, 5, 10, 15, 20% and calumite contents of 0, 5%. The specimens are tested for chloride ion penetration, carbonation, drying shrinkage and corrosion inhibition. As a result, the chloride ion penetration and carbonation depth of PMM using epoxy resin somewhat increases with increasing calumite contents, but those remarkably decreases depending on the polymer-binder ratios. The 28-d drying shrinkage shows a tendency to decrease with increasing polymer-binder ratio and calumite content. Unmodified mortars with calumite content of 5% did not satisfy quality requirement by KS. However, it was satisfied with KS requirement by the modification of epoxy resin in cement mortar. On the whole, the carbonation and chloride ion penetration depth of epoxy-modified mortars with calumite is considerably improved with an increase in the polymer-binder ratio regardless of the calumite content, and is remarkably improved over unmodified mortar. And, the replacement of the portland cement with the calumite has a marked effect in the corrosion-inhibiting property of the epoxy-modified mortars.

• Korean Journal of Environmental Agriculture
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• v.19 no.5
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• pp.401-418
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• 2000

1. Production of the artificial zeolite from coal ash Coal fly ash is mainly composed of several oxides including $SiO_2$ and $Al_2O_3$ derived from inorganic compounds remained after burning. As minor components, $Fe_2O_3$ and oxides of Mg, Ca, P, Ti (trace) are also contained in the ash. These components are presented as glass form resulting from fusion in the process of the combustion of coal. In other word, coal ash may refer to a kind of aluminosilicate glass that is known to easily change to zeolite-like materials by hydrothermal reaction. Lots of hot seawater is disposing near thermal power plants after cooling turbine generator periodically. Using seawater in the hydrothermal reaction caused to produce low price artificial zeolite by reduction of sodium hydroxide consumption, heating energy and water cost. As coal ash were reacted hydrothermally, peaks of quartz and mullite in the ash were weakened and disappeared, and new Na-Pl peaks were appeared strengthily. Si-O-Si bonding of the bituminous coal ash was changed to Si-O-Al (and $Fe^{3+}$) bonding by the reaction. Therefore the produced Na-Pl type zeolite had high CEC of 276.7 $cmol^+{\cdot}kg^{-1}$ and well developed molecular sieve structure with low concentration of heavy metals. 2. Utilization of the artificial zeolite in agro-environment The artificial zeolite(1g) could remove 123.5 mg of zinc, 164.7 mg copper, 184.4 mg cadmium and 350.6 mg lead in the synthetic wastewater. The removability is higher 2.8 times in zinc, 3.3 times in copper, 4.7 times in cadmium and 4.8 times in lead than natural zeolite and charcoal powder. When the heavy metals were treated at the ratio of 150 $kg{\cdot}ha^{-1}$ to the rice plant, various growth inhibition were observed; brownish discoloration and death of leaf sheath, growth inhibition in culm length, number of panicles and grains, grain ripening and rice yield. But these growth inhibition was greatly alleviated by the application of artificial zeolite, therefore, rice yield increased $1.1{\sim}3.2$ times according to the metal kind. In addition, the concentration of heavy metals in the brown rice also lowered by $27{\sim}75%$. Artificial Granular Zeolites (AGZ) was developed for the purification of wastewater. Canon exchange capacity was 126.8 $cmol^+{\cdot}kg^{-1}$. AGZ had Na-Pl peaks mainly with some minor $C_3S$ peaks in X-ray diffractogram. In addition, AGZs had various pore structure that may be adhere the suspended solid and offer microbiological niche to decompose organic pollutants. AGZ could remove ammonium, orthophosphate and heavy metals simultaneously. Mixing ratio of artificial zeolite in AGZs was related positively with removal efficiency of $NH_4\;^+$ and negatively with that of $PO_4\;^{3-}$. Root growth of rice seedling was inhibited severely in the mine wastewater because of strong acidity and high concentration of heavy metals. As AGZ(1 kg) stayed in the wastewater(100L) for 4days, water quality turned into safely for agricultural usage and rice seedlings grew normally.

• The Korean Journal of Pharmacology
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• v.24 no.1
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• pp.111-123
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• 1988

Neutrophil elastases were purified by a three step procedure consiting of one Sephadex G-75 and two HPLC elutions. The elastases cross-reacted with antibodies to human neutrophil elastase. Three bands with molecular weights between 26,000 and 29,700 were observed by gel electrophoresis. At each stage of purification the quantity of Zn increased, reaching molar ratio of 2:1 with elastase in the most purified samples. Calcium content. was seletively elevated during the earlier stages of purification but decreased to a ratio of 0.25 to 1 with elastase at the final step of purfication. Neutrophil elastase could be inhibited by EDTA, EGTA and 1,10-phenanthroline. EGTA inhbition was noncompetitive inhibition and reversible only if the time of preincubation was relatively short, indicating the instability of the apoenzyme. The concentration of chelator required to show significant inhibition of elastase was also dependent upon the stage of purity and the ionic strength of the reaction mixture. Inhibition by EGTA, followed by the removal of EGTA, could be reversed by Zn. In the presence of EGTA the enzyme could be returened to full activity by the addition of Zn, Mn and Ca, but not Mg or Na. All of the above evidence strongly supports human neturophil elastase could be a metalloenzyme as well as a serine protease.