• Title/Summary/Keyword: blocking effect

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Characterization of Water Treatment Membrane Using Various Hydrophilic Coating Materials (다양한 친수성 코팅소재를 이용한 수처리 분리막의 특성 평가)

  • Park, Yun Hwan;Nam, Sang Yong
    • Membrane Journal
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    • v.27 no.1
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    • pp.60-67
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    • 2017
  • Recently, the economic, social and environmental significance of the water industry is increasing significantly due to rapid global urbanization, population growth, and imbalance in demand and supply of water resulted by climate change. The type of these water industries are all different and they can be distinguished by the kinds of membranes used. Mainly, polymer materials that have excellent physical and chemical stability are used, but recently various methods of assigning hydrophilicity have been introduced due to their hydrophobic properties. In this study, hydrophilic polymers of four types were introduced into a commercially available hollow support to assign hydrophilicity. Furthermore, the morphology of the coated hollow support through FE-SEM was confirmed as well. Also the contact angle was measured to examine the degree of hydrophilicity of the coated hollow support with each polymer. Finally,.effect of different time on water permeability as well as the relationship between water permeability and hydrophilic polymers were investigated. As a result, the coating with 1 wt% of pluronic has good hydrophilicity degree, and shows the excellent water permeability without blocking the pore of the hollow fiber. Therefore, it can be concluded that the hydrophilic coating using pluronic polymer is most suitable as the water treatment.

Inhibitory Effects of Olmesartan on Catecholamine Secretion from the Perfused Rat Adrenal Medulla

  • Lim, Hyo-Jeong;Kim, Sang-Yong;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.4
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    • pp.241-248
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    • 2010
  • The present sutdy aimed to determine whether olmesartan, an angiotensin II (Ang II) type 1 ($AT_1$) receptor blocker, can influence the CA release from the isolated perfused model of the rat adrenal medulla. Olmesartan ($5{\sim}50{\mu}M$) perfused into an adrenal vein for 90 min produced dose- and time-dependent inhibition of the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (56 mM, a direct membrane-depolarizer), DMPP (100 ${\mu}M$) and McN-A-343 (100 ${\mu}M$). Olmesartan did not affect basal CA secretion. Also, in adrenal glands loaded with olmesartan (15 ${\mu}M$), the CA secretory responses evoked by Bay-K-8644 (10 ${\mu}M$, an activator of voltage-dependent L-type $Ca^{2+}$ channels), cyclopiazonic acid (10 ${\mu}M$, an inhibitor of cytoplasmic $Ca^{2+}$-ATPase), veratridine (100 ${\mu}M$, an activator of voltage-dependent $Na^+$ channels), and Ang II (100 nM) were markedly inhibited. However, at high concentrations ($150{\sim}300{\mu}M$), olmesartan rather enhanced the ACh-evoked CA secretion. Taken together, these results show that olmesartan at low concentrations inhibits the CA secretion evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) as well as by direct membrane depolarization from the rat adrenal medulla, but at high concentrations it rather potentiates the ACh-evoked CA secretion. It seems that olmesartan has a dual action, acting as both agonist and antagonist at nicotinic receptors of the isolated perfused rat adrenal medulla, which might be dependent on the concentration. It is also thought that this inhibitory effect of olmesartan may be mediated by blocking the influx of both $Na^+$ and $Ca^{2+}$ into the rat adrenomedullary chromaffin cells as well as by inhibiting the $Ca^{2+}$ release from the cytoplasmic calcium store, which is thought to be relevant to the $AT_1$ receptor blockade, in addition to its enhancement on the CA secreton.

Whitening Effect of Dayflower (Commelina communis L.) Extract by Inhibition of N-Linked Glycosylation Process and Melanogenesis (N-Linked Glycosylation 저해에 의한 닭의장풀 추출물의 미백효능)

  • Park, Sun-Hee;Lee, Bang-Yong;Lee, Seung-Hyun;Han, Chang-Sung;Kim, Jin-Guk;Kim, Kyoung-Tae;Kim, Ki-Ho;Kim, Young-Heui
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.1
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    • pp.73-78
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    • 2009
  • In order to investigate the potential of a Dayflower (Commelina communis L.) extract as an active in gredient for whitening cosmetics, we prepared aqueous Commelina communis L. extract We measured its mushroom tyrosinase inhibitory activity, cellular tyrosinase activity, and melanin synthesis inhibitory activity in B16 melanoma cells. It did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity. In a melanin synthesis inhibition assay using mouse B16-F10 melanoma cell, it suppressed melanin production up to 32% at a concentration of $1,000{\mu}/mL$ without cytotoxicity, and also reduced cellular tyrosinase activity to above 50 % above the concentration of $250{\mu}g/mL$. In study on the melanogenic protein expressions, it had especially influence on expression of tyrosinase protein, which is a well-known key protein on melanogenesis, and tyrosinase expression was gradually decreased in a dose-dependent. Dayflower also blocked N-glycosylation of TRP-2, but affected on the expression of TRP-1 rather than on blocking of N-glycosylation processing. Therefore, this result suggests that aqueous Commelina communis L. extract could be used as an active ingredient for whitening cosmetics.

Numerical Investigation of Flow Structures near Various Nozzle Exit Geometries of the Air Bearing (공기베어링의 노즐 형상 변화에 따른 출구면 근방의 유동구조에 대한 수치해석)

  • Park, Byung Ho;Han, Yong Oun;Park, Sang-Shin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.3
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    • pp.235-242
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    • 2014
  • To investigate pressure distributions on the shaft surface of the air bearing, the commercial CFD software was employed to study three different nozzle geometries to improve the nozzle performance: general drill-shaped, matched cube-shaped and trimmed exit nozzles. Under the influence of stagnation point, the maximum pressure was observed at the center of shaft surface for all cases. Owing to the blocking effect of a fine gap between the shaft surface and the nozzle exit, the drill-shaped nozzle has the rapid local pressure increase near the nozzle exit corner, generating the ring vortex in the radial direction within pressure ratio of 6.92, and its pressure becomes negative in a certain range of downstream. In comparison, the contoured nozzle showed a local pressure increase in the measured range of pressure ratios, but a negative pressure appeared within the pressure ratio of about 10. The trimmed nozzle was seemed to extend the high pressure zone near the stagnation point in the radial direction substantially, and no negative pressure was appeared in the whole range. Based on these observations, it is found that trimming nozzle exit becomes more effective for improving the performance than modifying the nozzle inside contour.

Fructose 1.6-diphosphate Prevents Cyclooxygenase-2 and Matrix Metalloproteinases Expression by Inhibition of UVB-induced Signaling Cascades in HaCaT Keratinocytes (인체각질형성세포에서 Fructose 1,6-diphosphate의 자외선에 의해 유도되는 Cyclooxygenase-2 and Matrix Metalloproteinases의 발현억제기전)

  • Soo Mi, Ahn;Ji Hyun, Kim;Byeong Gon, Lee;Soo Hwan, Lee;Ih Seoup, Chang
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.2
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    • pp.247-251
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    • 2004
  • UV radiation exerts various influences in the skin, including photoaging and inflammation (1). The MMPs (Matrix metalloproteinases), which are induced by UV irradiation, can degrade matrix proteins, and these results in a collagen deficiency in photodamaged skin that leads to skin wrinkling. It has been known that the production of PGE$_2$ stimulates MMPs expression, and inhibits procollagen (2). Thus, it is possible that the induction of MMPs and the inhibition of matrix protein synthesis by UV -induced PGE$_2$ may play some role in UV-induced collagen deficiency in photoaged skin. Fructose-1,6-diphosphate (FDP), a glycolytic metabolite, is reported to have cytoprotective effects against ischemia and postischemic reperfusion injury of brain and heart, presumably by augmenting anaerobic carbohydrate metabolism (3). And also, FDP significantly prevent skin aging by decreasing facial winkle compared with vehicle alone after 6 months of use. We studied the mechanism of anti-aging effect of FDP on UVB-irradiated HaCaT keratinocyte model. FDP has protective role in UVB injured keratinocyte by attenuating prostaglandin E$_2$ (PGE$_2$) production and COX-2 expression. And FDP also suppressed UVB-induced MMP-2 expression. Further, to delineate the inhibition of UVB-induced COX-2 and MMPs expression with cell signaling pathways, treatment of FDP to HaCaT keratinocytes resulted in marked inhibition of UVB-induced phosphorylation of ERK1/2, JNK. It also prevents UV induced NFB translocation, which are activated by cellular inflammatory signal. Our results indicate that FDP has protecting effects in UV-injured skin aging by decreasing UVB-induced COX-2 and MMPs expression, which are possibly through blocking UVB-induced signal cascades.

Effect of Uniconazole and Silver Thiosulfate Treatment on Reduction of Ozone Injury in Snap Bean Plants (Uniconazole과 Silver Thiosulfate 처리(處理)가 강남콩의 오존피해(被害) 경감(輕減)에 미치는 효과(效果))

  • Ku, Ja Hyeong;Won, Dong Chan;Cho, Jeong Hee;Shin, Dae Shik
    • Korean Journal of Agricultural Science
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    • v.19 no.2
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    • pp.161-169
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    • 1992
  • Studies were conducted to examine the effects of single or combined treatment of uniconazole [(E)-1-(4-chlorophenyl)-4, 4-dimethyl 2(1, 2,-4-triazol-1-yl)-1-penten-3-ol)] and silver thiosulfate (STS) on reducing ozone injury to snap beans (Phaseolus vulgaris L. 'Strike'). Two weeks after seeding, plants were given a soil drench of uniconazole(XE-1019) solution at concentrations of 0.001, 0.005 and 0.025 mg/pot, and then two days prior to ozone fumigation, 0.3 and 0.6 mM STS containing 0.01% Tween-20 were also sprayed. Uniconazole was effective in providing protection against ozone injury through increase activities of free radical scavengers such as superoxide dismutase (SOD) and peroxidase (POD) as well as the increase of chlorophyll content and stomatal resistance resulted from plant growth retardation. The phytoprotective effects of STS seemed to be related to its properly of blocking the ethylene action and increasing activities of SOD and POD. Even at low concentrations, a combined treatment with uniconazole drench, STS spray significantly reduced ozone injury compared to single application.

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Sun Protection Factor (SPF) Assessment of the Sunscreen Composed of Natural Substances (천연물을 이용한 자외선차단제의 자외선차단지수(SPF) 평가)

  • Oh, In Young;Kim, So Young;Suk, Jang Mi;Jung, Sang Wook;Park, Jin Oh;Yoo, Kwang Ho;Li, Kapsok;Kim, Beom Joon;Kim, Myeung Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.2
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    • pp.141-148
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    • 2013
  • The harmful effects of ultraviolet (UV) radiation by increasing sun exposure are making people use sunscreens casually. To keep pace with this trend, many researches about mixing different ingredients or extracting effective ingredients from natural materials are conducted by cosmetics industry. In the present study, we evaluated the UV blocking effect of the sunscreen containing Scutellaria baicalensis Georgi extract. 10 volunteers were measured by minimal erythema dose (MED) and sun protection factor (SPF) of each product. The SPF results were $34.52{\pm}2.13$ and $32.67{\pm}1.44$ in the sunscreen containing Scutellaria baicalensis Georgi extract and that of not containing the substance, respectively. Although the difference of SPF between two products was statistically not significant, it is thought to be meaningful in evaluating clinical effects of the sunscreen using natural substance to humans without any adverse reaction.

Inhibition of ERK1/2 Activation and Cytoskeleton Rearrangement by the Recombinant Protein of Plasminogen Kringle 5 (Plasminogen kringle 5 재조합 단백질에 의한 ERK1/2 활성화 및 세포골격 재배열 억제)

  • Ha, Jung-Min;Kim, Hyun-Kyung;Kim, Myoung-Rae;Joe, Young-Ae
    • Journal of Life Science
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    • v.16 no.7 s.80
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    • pp.1199-1206
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    • 2006
  • Plasminogen kringle 5 is a potent inhibitor of endothelial tell proliferation like an endogenous angiogenesis inhibitor, angiostatin consisting of plasminogen kringles 1-4. In this study, we produced the recombinant protein of plasminogen kringle 5 (PK5) employing an Pichia expression system and examined its. effect on~endothelial cell migration and its possible inhibitory mechanism. PK5 was expressed in Pichia pastoris GS115 by fusion of the cDNA spanning from Thr456 to Phe546 to the secretion signal sequence of a-factor prepro-peptide. After methanol induction, the secreted PK5 was purified by using S-spin column. SDS-PACE analysis of the purified protein showed one major band of approximately 10kDa. In in vitro migration assays, the purified protein inhibited dose-dependently the migration of human umbilical endothelial cells (HUVECs) induced by basic fibroblast growth factor (bFGF) or vascular endothelial growth factor (VEGF) with an $IC_{50}$ of approximately 500nM. Accordingly, it inhibited bfGF-stimulated extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in HUVECs at 500nM. In addition, it also potently inhibited bFGF-induced cytoskeletal rearrangement of HUVECs. Thus, these results suggest that Pichia-produced PK5 effectively inhibits endothelial cell migration, in part by suppression of ERK1/2 activation and blocking cytoskeleton rearrangement.

Helixor A Inhibits Angiogenesis in vitro Via Upregutation of Thrombospondin-1 (Helixor A는 시험관 내에서 thrombospondin-1의 상승조절을 통해 신혈관생성을 억제한다.)

  • Yeom Dong-Hoon;Hong Kyong-Ja
    • Journal of Life Science
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    • v.15 no.6 s.73
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    • pp.895-903
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    • 2005
  • Thrombospondin-1 (TSP-1), a negative regulator in tumor growth and angiogenesis, is cell-type specifically regulated under pathological conditions or by extracellular stimuli, and the regulation of TSP-1 gene expression is important for developing new approaches in tumor therapy. Mistletoe is a parasitir plant that have been used for immunomodulation and antitumor therapy. Helixor A is an aqueous part of mistletoes extract. Here we showed that TSP-1 expression was significantly induced at both mRNA and protein levels in the Hepatocarcinorna cell line (Hep3B) and primary bovine endothelial cell line (BAE) exposed to Helixor A. Our promoter analysis confirmed that the expression of TSP-1 gene was regulated by Helixor A at the transcriptional level. In cell invasion assay, the conditioned media obtained from treatment of these cells significantly reduced the number of invasive cells and also inhibited capillary-like tube formation of BAE cells on Matrigel. Moreover, the inhibitory efforts of the conditioned media on cell invasion and tube formation were reversed by blocking with anti-TSP-1 neutralizing antibodies, suggesting that TSP-1 is involved in Helixor A-indured antiangiogenic effect. Taken together, our results suggest that Helixor A have an antiangiogenic effects through upregulation of TSP-1.

Application of Oryza sativa (Rice) Bran Oil as an Anti-pollution Cosmetic Material (쌀겨오일의 안티폴루션 화장품 소재로써의 응용)

  • Kang, Hae-Ran;Jung, So Young;Heo, Hyojin;Cha, Byungsun;Brito, Sofia;Lee, So Min;Yeo, Hye Lim;Yoo, Kyung Wan;Kwak, Jun Soo;Kwak, Byeong-Mun;Lee, Mi-Gi;Bin, Bum-Ho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.3
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    • pp.237-245
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    • 2021
  • Particulate matter and ultra-particle matters generally refer to very small floating dust, such as 1/6 to 1/7 and 1/20 to 1/30, respectively, compared to the thickness of human hair, and contain various types of heavy metal ions. In addition to breathing, particle matters (PM) that flows in through the gaps in the pores of the skin can induce health problems in the body's tissues and skin, so it must be removed by blocking the inflow or by washing. Through this study, we confirmed the possibility that heavy metal ions can be adsorbed and removed by using Oryza sativa (Rice) bran oil (OSBO). In addition, the cell viability is much higher than that of grain-derived components through cytotoxicity experiments, and the cytoprotective effect of an external stimulus source can be expected. It was confirmed that the expression amount of COL1A1 mRNA increased, and accordingly, it was believed that wrinkles that might be caused by moisture lost by heavy metal ions in fine dust could be alleviated. Based on the results of these experiments, we tried to present a cosmetics containing OSBO, which is a wash-off formulation, in order to finally remove heavy metals.