• Title/Summary/Keyword: NF membrane

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Influence of inorganic compounds on nanofiltration membrane fouling with Al hydrolysis products (알루미늄 수화물 나노여과 막오염에 대한 공존염의 영향에 관한 연구)

  • Choi, Yang-Hun;Kweon, Ji-Hyang
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.4
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    • pp.479-488
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    • 2011
  • Nanofiltration was performed with polyaluminium chloride solutions at different pH conditions to understand effects of inorganic compounds on aluminum hydrolysis products, i.e., three distinctive groups of aluminum species: polymeric Al at low pH; $Al(OH)_3$ at neutral pH; and ${Al(OH)_4}^-$ at high pH. The PACl solution was prepared to be approximately 4.0mM and adjusted to the designated pH. The influence of inorganic compounds on Al species fouling was investigated with 4.9mM $CaCl_2$ and 3.5mM $MgSO_4$ because $Ca^{2+}$, $Mg^{2+}$, $Cl^-$, ${SO_4}^{2-}$ are the most common inorganics in the drinking water. NF membrane fouling was measured by flux decline rate. The impact of $CaCl_2$ was not significant on the individual Al hydrolysis products fouling. However, the flux decline rate was drastically changed in the presence of $MgSO_4$. The concentration of particulate matters was considerably increased possibly due to interaction between Al species and ${SO_4}^{2-}$ where $MgSO_4$ was introduced. The particulates were accumulated on the membrane and enhanced the hydraulic resistance of the cake layer. In addition, conductivity removal of the membrane was decreased when Al-hydroxide was dominant due to reduction of membrane surface charge. The rejection of $Ca^{2+}$and $Mg^{2+}$ were considerably different, which implys that composition of inorganics paly a role on conductivity removal.

Current Research Trends on Surface Modification of Pressure-driven Membranes for Fouling Mitigation (압력 구동 기반 분리막의 막 오염 저감을 위한 표면 개질 방법 최신 연구 동향)

  • Jun, Byung-Moon;Lee, Hyung Kae;Kim, Woo Jeong;Park, Jihun;Kim, Jong Hyeok;Kwon, Young-Nam
    • Membrane Journal
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    • v.28 no.1
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    • pp.1-20
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    • 2018
  • Fresh water is an important resource for humans, and pressure-driven membrane technology has been widely known as an energy-efficient method to obtain water resource. However, membrane fouling phenomenon, which is one of the major issue during operation, deteriorates membrane permeability. These fouling is usually affected by interaction between surface of membrane and various foulants, therefore, modification of membrane's surface is one of the methods to improve fouling-resistance. This review focuses on the method to modify surface of pressure-driven membranes such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO). Specifically, there are two different surface modification methods: (1) adsorption and coating as the physical modification methods, (2) cross-linker, free radical polymerization (FRP), atom transfer radical polymerization (ATRP), plasma/UV-induced polymerization as the chemical modification methods. This review introduces the physico - chemical surface modification methods reported in recent papers and suggests research directions for membrane separation which can increase membrane fouling resistance.

The Effects of Hyangsapyeongwisan on Gastric Mucosal Lesions Induced by Indomethacin (Indomethacin으로 유발된 생쥐의 위 점막 손상에 대한 향사평위산(香砂平胃散)의 보호 효과)

  • Choi, Heung-Min;Lim, Seong-Woo
    • The Journal of Internal Korean Medicine
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    • v.25 no.3
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    • pp.518-528
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    • 2004
  • This study was carried out to investigate the effects of Hyangsapyeongwisan(HP) on gastric mucosal lesions induced by indomethacin in mice. The control group consisted of gastro-inflammation elicited mice. The sample group consisted of mice given HP after onset of gastro-inflammation. In common morphological and histochemical change, various cell abnormalities were observed in the control group, such as mucous surface cell, peanut cell, surface epithelial cell, goblet cell abnormalities, all caused hemorrhagic erosion. The sample group was the same as the control group. In the immunohistochemical change, the distributions of COX-I, BrdU treated with HP were notably higher than those of the control group(p$NF-{\kappa}B$, COX-2, PKC, IL-12B in mice treated with HP were notably lower than those of the control group(p

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Landfill Leachate Treatment and Boron Removal by Reverse Osmosis (RO막을 이용한 매립지 침출수 처리 및 붕소 제거)

  • Jung, Soojung;Na, Sukhyun;Bae, Sangok;Lim, Byungjin
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.657-662
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    • 2012
  • This study was carried out to evaluate the removal rate of organic and inorganic matters from landfill leachate using pre-treatment process as coagulation and limonite adsorption, and membrane process as RO (reverse osmosis) and NF(nanofiltration). By adding limonite adsorption as pre-treatment process, about 40% of organic matters in leachate was removed through pre-treatment process and 74.7% of boron was removed after RO process without pH adjustment. The rejection rate of boron in RO process mainly depends on the pH and increased at pH value of 10. RO process was performed as two stage system adjusting pH condtion to 7 and 10 in second RO stage for boron removal. Most (>90%) of TOC, Cl- and inorganic matters as Ca was rejected in first RO stage, the residue was rejected in second RO and the rejection rate was above 97%. Considering economic efficiency of operation cost, NF substituted for the first RO and total removal rate of TOC was above 90%. Through RO system toxicity to Daphnia in leachate was removed completely.

The Phosphorylation Status of Merlin Is Important for Regulating the Ras-ERK Pathway

  • Jung, Ju Ri;Kim, Hongtae;Jeun, Sin-Soo;Lee, Joo Yong;Koh, Eun-Jeoung;Ji, Cheol
    • Molecules and Cells
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    • v.20 no.2
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    • pp.196-200
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    • 2005
  • The neurofibromatosis type2 (NF2) tumor suppressor gene product, merlin, is structurally related to the ezrin-radixin-moesin (ERM) family of proteins that anchor the actin cytoskeleton to specific membrane proteins and participate in cell signaling. However, the basis of the tumor suppressing activity of merlin is not well understood. Previously, we identified a role of merlin as an inhibitor of the Ras-ERK signaling pathway. Recent studies have suggested that phosphorylation of merlin, as of other ERM proteins, may regulate its function. To determine whether phosphorylation of merlin affects its suppression of Ras-ERK signaling, we generated plasmids expressing full-length merlin with substitutions of serine 518, a potential phosphorylation site. A substitution that mimics constitutive phosphorylation (S518D) abrogated the ability of merlin to suppress effects of the Ras-ERK signaling pathway such as Ras-induced SRE transactivation, Elk-mediated SRE transactivation, Ras-induced ERK phosphorylation and Ras-induced focus formation. On the other hand, an S518A mutant, which mimics nonphosphorylated merlin, acted like wild type merlin. These observations show that mimicking merlin phosphorylation impairs not only growth suppression by merlin but also its inhibitory action on the Ras-ERK signaling pathway.

Galangin and Kaempferol Suppress Phorbol-12-Myristate-13-Acetate-Induced Matrix Metalloproteinase-9 Expression in Human Fibrosarcoma HT-1080 Cells

  • Choi, Yu Jung;Lee, Young Hun;Lee, Seung-Taek
    • Molecules and Cells
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    • v.38 no.2
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    • pp.151-155
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    • 2015
  • Matrix metalloproteinase (MMP)-9 degrades type IV collagen in the basement membrane and plays crucial roles in several pathological implications, including tumorigenesis and inflammation. In this study, we analyzed the effect of flavonols on MMP-9 expression in phorbol-12-myristate-13-acetate (PMA)-induced human fibrosarcoma HT-1080 cells. Galangin and kaempferol efficiently decreased MMP-9 secretion, whereas fisetin only weakly decreased its secretion. Galangin and kaempferol did not affect cell viability at concentrations up to $30{\mu}M$. Luciferase reporter assays showed that galangin and kaempferol decrease transcription of MMP-9 mRNA. Moreover, galangin and kaempferol strongly reduce $I{\kappa}B{\alpha}$ phosphorylation and significantly decrease JNK phosphorylation. These results indicate that galangin and kaempferol suppress PMA-induced MMP-9 expression by blocking activation of NF-${\kappa}B$ and AP-1. Therefore, these flavonols could be used as chemopreventive agents to lower the risk of diseases involving MMP-9.

Effect of Sopung-tang on Glutamate-Induced Apoptosis in C6 Glial Cells (소풍탕(疎風湯)이 Glutamate에 의한 C6 Glial Cell의 Apoptosis에 미치는 영향)

  • Jeong, Seung-Won;Choi, Chul-Won;Kim, Bong-Sang;Moon, Byung-Soon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.6
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    • pp.1423-1430
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    • 2008
  • The water extract of Sopung-tang(SPT) has been traditionally used for treatment of psycologic disease and brain damage in oriental medicine. However, little is known about the mechanism by which the water extract of SPT rescues cells from these disease. Therefore, this study was designed to investigate the effect of SPT on the glutamate-induced toxicity of rat C6 glial cells. SPT have protective effects in glutamate-induced toxicity, which was revealed as apoptosis characterized by chromatic condensation and fragmentation and the loss of mitochondrial membrane potential in C6 glial cells. Also, SPT have inhibited the active form of caspase-3 and PARP and significantly protected the apoptotic phenomena by glutamate toxicity in C6 glial cells. However, SPT significantly recovered the depletion of GSH and inhibited the generation of ROS by glutamate in C6 glial cells. In addition, both SPT and antioxidants such as GSH and NAC protected the glutamate-induced cytotoxicity in C6 glial cells, indicating that SPT possibly have antioxidative effect. Specially, SPT were showed transcriptional factor significantly increased the activation of NF-${\kappa}B$ using the analysis of NF-${\kappa}B$ luciferase reporter system in C6 glial cells. These NF-${\kappa}B$ activation protected cells from glutamate-induced toxicity to generate the heme oxygenase-1(HO-1). Taken together, we suggest that SPT have protective effects in glutamate-induced toxicity via a antioxidative mechanism.

Effects of Vespae Nidus on Peroxynitrite Production and Protein Expression of Proinflammatory Mediators (노봉방(露蜂房)이 t-butylhydroxyperoxide에 의한 Peroxynitrite 생성과 염증성 단백질 발현에 미치는 영향)

  • Jang, Jae-Shik;Jeong, Ji-Cheon;Shin, Hyeon-Cheol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1499-1505
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    • 2007
  • Peroxynitrite ($ONOO^-$) is a reactive oxidant formed from superoxide anion radical (${\cdot}\;O_2-$) and nitric oxide (NO), which can oxidize cellular components such as essential protein, non-protein thiols, DNA, low-density lipoproteins and membrane phospholipids. ${\cdot}\;O_2-$ and $ONOO^-$ have contributed to the pathogenesis of diseases such as stroke, heart disease, Alzheimer's disease and atherosclerosis. Because of damaging effects of ${\cdot}\;O_2-$ and $ONOO^-$ oxidants, Vespae Nidus, which has been known to strengthen the kidneys to preserve the vital energy. was tested as a potential specific scavenger of those oxidants. In this study, the viability of Vespae Nidus (1, 10, 50 g/ml) to scavenge ${\cdot}\;O_2-$, NO, $ONOO^-$ and so to protect cells against tert-butylhydroxyperoxide (t-BHP) induced cell death was tested. The levels of ${\cdot}\;O_2-$ and $ONOO^-$ were detected by staining with DCFH-DA and DHR 123, respectively. Protein expression levels of COX-2, iNOS and $NF{-\kappa}B$ were assayed by western blot. Vespae Nidus blocked t-BHP-induced cell death in a dose-dependent fashion. Vespae Nidus inhibited t-BHP-induced production of ${\cdot}\;O_2-$, NO and $ONOO^-$ in YPEN cells. The lipid peroxide level was increased and glutathione level was decreased in lipopolysaccharide (LPS)-treated ICR mouse, whereas the ones in the Vespae Nidus-administered group were regulated beneficially. Vespae Nidus inhibited the expression of COX-2, iNOS and NF-κB (p65 and p50) genes in LPS-treated ICR mouse. The present study suggests that Vespae Nidus is a powerful antioxidant and promotes cellular defense activity by scavenging the toxic oxidants such as ${\cdot}\;O_2-$ and $ONOO^-$.

Development of customized and energy-saving process for wastewater reuse utilizing UF/NF membrane (UF/NF 분리막을 활용한 수요자 맞춤형 / 에너지 절약형 재이용수 공정기술 개발)

  • Hong, Min;Hwang, Hyun-Seob;Park, Ock-Kwon;Kim, Yong-Lim
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.712-712
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    • 2012
  • 하 폐수 처리방류수를 물리적, 화학적 그리고 생물학적 기술을 이용하여 처리한 후 재활용수로 이용하고자 하는 새로운 노력들이 진행되고 있지만 국내의 경우 방류수 재활용 기술과 처리수의 재이용에 대한 평가기술이 선진국에 비해 초기 단계에 있어 이 분야에 대한 적극적인 기술개발이 요구된다. 막 분리 기술을 이용한 처리 수는 소독 등의 추가적인 처리 없이 살수용수나 수경용수로 이용이 가능하며, 잔류염소를 유지시킬 경우 화장실 세정용수로의 이용도 가능하며, 또한 후처리 기술을 조합하면 고급 공업용수 등으로 사용가능하므로 선진기술로서 수요조건에 맞게 전 후 처리를 조합한 수요자 맞춤형 재이용수 공정기술을 개발할 필요가 있다. 이에 효율적인 하 폐수 재이용을 이용하여 농업용수(축산 음용수, 첨단 수출원예용수, 첨단 농업용수, 농산업 클러스터 복합 곡물 용수), 원예용수(원예단지), 공업용수 등의 다양한 용도에 활용 가능한 수요자 맞춤형 모듈 및 공정 개발을 수행하였다. 개발된 공정은 AOP 및 막 세정 시스템을 이용한 새로운 공정으로, AOP 시스템은 전기 이온 모듈을 통해 OH 라디칼을 생성 및 염분 제거 효율을 극대화 하여 오염 물질을 산화시키는 공정이며, FDA 시스템은 탁도가 높은 원수가 과다 유입 될 경우 후단 여과 막의 부하를 줄이는 역할을 하며, 부유 물질을 여과 시킨다. 막 세정 시스템은 미세 입자를 구성된 기포를 이용하여 눈에 보이지 않는 곳 까지 세척하며, 살균 작용을 하며, 분리 막의 성능을 증대 시킨다. 이어 UF 분리 막 시스템은 원수의 미세불순물, 박테리아, 스케일 물질 등을 제거하며, NF 시스템을 통하여 미립자, 박테리아 유기 화합물 및 2가 염 제거를 하여 재이용수를 생산하는 공정을 개발하였다. 개발된 수요자 맞춤형 공정은 하수 재이용 기술의 이용 목적 및 수요자별로 맞춤형으로 운영이 가능하며, 개발된 세척 기술은 분리 막 세정 유지관리비 및 에너지를 저감 할 수 있으며, 현장 적용의 실증화 과정을 거쳐 공정 기술을 신뢰도를 향상하고, 보유 기술을 수요자 맞춤형으로 업그레이드함으로써 기술의 경쟁력 및 고품질의 하수 재이용 기술의 새로운 방향을 제시 할 수 있을 것으로 판단된다.

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Ginsenoside compound K protects human umbilical vein endothelial cells against oxidized low-density lipoprotein-induced injury via inhibition of nuclear factor-κB, p38, and JNK MAPK pathways

  • Lu, Shan;Luo, Yun;Zhou, Ping;Yang, Ke;Sun, Guibo;Sun, Xiaobo
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.95-104
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    • 2019
  • Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-${\alpha}$, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (${\Delta}{\Psi}m$) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor $(NF)-{\kappa}B$, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, $NF-{\kappa}B$ nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the $NF-{\kappa}B$, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.