• Title/Summary/Keyword: barrier function

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Effects of Passivation Thin Films on the Optical Properties of the Green Organic Light Emitting Diodes (페시베이션 박막이 녹색 유기발광다이오드의 광학특성에 미치는 영향)

  • Mun, Sae Chan;Lee, Sang Hee;Park, Byung Min;Pyee, Jaeho;Chang, Ho Jung
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.1
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    • pp.11-15
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    • 2016
  • The organic light emitting diodes (OLEDs) have been studied as large flexible displays, light source and hard wares of internet of things. However, OLEDs show some drawbacks in terms of external environments due to the low work function of the metals and the reactive organic materials. In particular, the operation functions of the OLEDs tend to deteriorate rapidly by exposing the oxygen and moisture. So as to prevent it, domestic and overseas studies underway in various method such as ALD, PVD, CVD. But it has complex process and high cost. Therefore In order to protect devices from the external environments, it is important to develop the passivation thin films of low-cost and simple process which can prevent the devices from the penetration of the oxygen and moistures. In this study, to improve the reliability, passivation thin films were coated onto the green OLEDs by spin coating method and investigated the changes of the optical properties of the prepared devices at various doping concentrations of sodium alginate (SA). The passivation solutions were synthesized by using polyvinyl alcohol (PVA) host material with a dopant of SA which were added with the amounts of 10, 20 and 40 wt% into the PVA. As a result, the best barrier properties of the OLEDs were obtained for the samples with 40 wt% SA. Finally, the passivation films can be optimized by using the mixture solution of PVA and SA materials.

Effect of Zanthoxylum piperitum Extract on Human Skin Protection from UVB by Regulation of COP1 and PPAR-α (초피나무 열매 추출물의 COP1 및 PPAR-α 조절을 통한 자외선에 대한 피부 보호 효과)

  • Kim, Yun-Sun;Kim, Yumi;Lee, Sanghwa
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.4
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    • pp.393-401
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    • 2016
  • Ultraviolet (UV) irradiation from the sun is the primary environmental factor that causes skin damages including skin cancer and premature skin aging. Because, even the most powerful sunscreen can't always afford enough protection, it is necessary to enhance the defensive power of skin against UV. Recently, constitutive photomorphogenic protein-1 (COP1) has shown to contribute to the regulation of UVB response of keratinocytes. In this study, we represent that COP1 and its associated protein, de-etiolated 1 (DET1), might participate in photoaging process in human skin as Arabidopsis COP1 does sun-protective function in plants. After UVB irradiation, the decrease of COP1 and DET1 mRNA expression was followed by the increase of c-Jun total protein. Moreover, transfection with DNA vectors expressing COP1 and DET1 down-regulated the c-Jun total protein. We found that Zanthoxylum piperitum extract (ZE) up-regulated the expression of COP1 and DET1 on human keratinocytes, and inhibited the expression of MMP1 which is one of the genes regulated by c-Jun signal. In addition, ZE has been reported to stimulate PPAR-${\alpha}$ and strengthen the skin barrier. We found that ZE decreased the UVB-induced IL-6 and IL-8 in NHEK cells. In human study, ZE protected skin against UV-B induced erythema and erythema-induced pigmentation. These results indicate that ZE could be useful for the protection against the adverse effects of UV irradiation through various mechanisms.

Clostridium difficile Toxin A Inhibits Wnt Signaling Pathway in Gut Epithelial Cells (대장상피세포 속 Wnt 신호 경로에 대한 C. difficile 톡신A의 영향)

  • Yoon, I Na;Kim, Ho
    • Journal of Life Science
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    • v.28 no.9
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    • pp.1016-1021
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    • 2018
  • Clostridium difficile toxin A causes pseudomembranous colitis. The pathogenesis of toxin A-induced colonic inflammation includes toxin A-dependent epithelial cell apoptosis, resulting in the loss of barrier function provided by epithelial cells against luminal pathogens. Toxin A-dependent epithelial cell apoptosis has been linked to toxin A-induced production of reaction oxygen species and subsequent p38MAPK activation; $p21^{CIP1/WAF1}$ upregulation-dependent cell cycle arrest; cytoskeletal disaggregation; and/or the induction of Fas ligand on epithelial cells. However, the molecular mechanisms underlying toxin A-induced apoptosis remain poorly understood. This study tested whether toxin A could block the Wnt signaling pathway, which is involved in gut epithelial cell proliferation, differentiation and antiapoptotic progression. Toxin A treatment of nontransformed human colonocytes (NCM460) rapidly reduced ${\beta}$-catenin protein, an essential component of the Wnt signaling pathway. Exposure of mouse ileum to toxin A also significantly reduced ${\beta}$-catenin protein levels. MG132 inhibition of proteasome-dependent protein degradation resulted in the recovery of toxin A-mediated reduction of ${\beta}$-catenin, indicating that toxin A may activate intracellular processes, such as $GSK3{\beta}$, to promote degradation of ${\beta}$-catenin. Immunoblot analysis showed that toxin A increased active phosphorylation of $GSK3{\beta}$. Because the Wnt signaling pathway is essential for gut epithelial cell proliferation and anti-apoptotic processes, our results suggest that toxin A-mediated inhibition of the Wnt signaling pathway may be required for maximal toxin A-induced apoptosis of gut epithelial cells.

Ecological Functions and Losses of Traditional Korean Village Groves

  • Lee, D.-W.;Park, C.-R.
    • The Korean Journal of Quaternary Research
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    • v.18 no.2 s.23
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    • pp.65-66
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    • 2004
  • There have been groves, in many cases, along with hedgerows and remnant forests around a traditional Korean village. A village grove is very closely connected to the life of residents. Sometimes it was a holy place where important village festivals were held, and became a resting place for farmers, especially in sunny summer. As a matter of fact, it is noted that traditional Korean village groves had been fostered for many purpose as religion, Confucianism, scenery, sanitation, traffic guard, public security, agriculture, hunting, and military and public uses were included in Chosun Govemor General(1938). Village groves were usually located at the outlet of watershed inside which a village was built. In addition, village groves used to be established along part of mountain ranges, streams and streets. A unique type of village grove, called bibosoop was fostered especially where the outlet of watershed was largely opened. In other cases, it was placed where a part of mountain range was relatively low, or where village residents were likely to see ugly objects such as a huge cliff, stony upland with an unvegetated area and the like(Kim and Jang 1994). In a sense, a sheltebelt is a sort of bibosoop as it is a landscape element to complement places that are exposed to strong winds. However, it is comparable to other typical bibosoop that is situated at a topographically very specific zone of watershed. In this paper, we will address potential functions of Korean village groves from a perspective of modern landscape ecology and show current status of some remnants, based on preliminary surveys. A village grove functions as barrier or filter of objects such as water, nutrients, and other elements and habitat of wildlife (park et al. 2003, Lee 2004). The village grove slows down the flow of water and air, maintains soil moisture an hinders soil erosion, enabling cultivation of crops and bringing up creatures nearby. It contributes to enhancing biodiversity. Birds rest on shrubby and woody trees of the element. Presumably, other organisms may also inhabit the village groves and take advantage of it when those move from a forest patch to others. Emerging insects acclimate themselves in the shade of the green space before they fly to sunny air. Besides the village grove acts as a component of agroforestry system as leaf litter is shed from a grove to an asjacent agricultural area, and transformed into green manure(Lee 2004). By the way, many of the landscape elements were destroyed or declined in Koea during the past several decades. The losses have been parallel or linked to environmental degradation. Unfortunately, we have a little reliable data as for how many groves have disappeared in Korea until now. There has been no complete census on the village groves in Korea, and the viewpoints of survey were to a degree different depending on surveyors. So, it is difficult to analyze the temporal and spatial change of village groves. Currently, national inventory data of Korean village groves are available in three reports. We reviewed the locations of village groves and arranged those according to the present administrative units, DONG. With the limited data, we found that at least 484 of village groves were recorded in South Korea. Among all provinces, village groves were most in Gyeongsanbuk-Do Province and least in Chungcheongbuk-Do Province(Table 1). This is a preliminary report prepared while some quantitative data regarding functions and lossers of the village groves are being collected. More detailed data will be introduced in the near future.

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The Expression Pattern of the Tight Junction Protein Occludin in the Epidermal Context When Comparing Various Physical Samples (신체 부위별 표피에서 밀착연접 단백질 중 오클루딘의 발현도 연구)

  • Kim, Ji Sook;Jang, Hyung Seok
    • Korean Journal of Clinical Laboratory Science
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    • v.47 no.4
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    • pp.267-272
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    • 2015
  • 'Tight junctions (TJ)' have recently been identified in the granular cell layer of the human epidermis, where they contribute to the normal adhesion between keratinocytes and to the physiologic barrier function of the epidermis. Among the TJ proteins in the epidermis, occludin is an important transmembrane protein, which is considered as a major component. The purpose of this study is to investigate whether regional variation exists in the expression of the tight junction protein occludin in normal human epidermis. Indirect immunofluorescence staining for occludin was performed with specimens taken from different areas of normal skin (4 from each of 7 different anatomical sites, including the scalp, face, posterior neck, upper arm, abdomen, lower back, and inner thigh). The degrees of the expression-intensity in each specimen were estimated with the reciprocals of positive end-point titer of occludin in an indirect immunofluorescence study. The highest degree expression-intensity of the TJ protein occludin among the different areas of normal epidermis was observed on the face and abdomen with a titer of 600 (p=0.001). The lowest intensity of expression of occludin was seen in the epidermis from the upper arm. Skin specimens from the scalp, neck, back, and leg demonstrated intermediate degrees of the expression in intensity. The expression of occludin in the skin samples obtained from different locations of the body showed a statistically significant variation. This suggests that there is a certain degree of regional variation in the expression-intensity of TJ protein 'occludin' in the human epidermis.

A Study on the Use of Police Force in the Public Assembly: Focused on the Vehicle-wall-blocking and water cannon (집회현장에서의 경찰의 물리력 사용현황과 개선방안: 차벽과 물포 사용을 중심으로)

  • Hwang, Mun-Gyu
    • Korean Security Journal
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    • no.50
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    • pp.307-337
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    • 2017
  • The freedom of assembly is the fundamental freedoms guaranteed by the Constitution. However, as far as our reality is concerned, the freedom of assembly is guaranteed only when it is under the control of the police, and otherwise it is perceived as an object to be suppressed. Police say even that they will not tolerate even a small illegal law while referring to the "broken window theory". Therefore, regardless of the peaceful nature of the rally, it is too obsessed with 'compliance'. This attitude is causing the citizens who participated in the assembly to be put to the object to be suppressed. This paper analyzes the requirements and current status of police force, focusing on the vehicle-wall-blocking and water cannon as a means of using the police force, which is a recent problem, and suggests ways to improve it. First of all, the installation of the wall cuts off the essential communication function of the assembly by separating the meeting place from the object of protest. Thus, despite the warning for prevention in the face of illegal acts, other than installing a barrier, it should be allowed only in the 'urgent case where there is a risk of causing damage to the life, body or property of the person'. Without this urgency, the vehicle-wall-blocking should not be allowed to be proactive as well as preventive. Secondly, the water cannon is a police force that is likely to harm people's life and body. Therefore, aiming shots, which could pose a significant risk to the human body, should in principle be prohibited. However, considering its risk, it should be supplementary used only when there is no other alternative, only when the direct risk to the legal interest of the other person or the order of public well-being is 'obvious'. In addition, as for the use standard of such a thing, it is necessary to be specified by law.

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A Study on the Constructing Discrete Fracture Network in Fractured-Porous Medium with Rectangular Grid (사각 격자를 이용한 단열-다공암반내 분리 단열망 구축기법에 대한 연구)

  • Han, Ji-Woong;Hwang, Yong-Soo;Kang, Chul-Hyung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.4 no.1
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    • pp.9-15
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    • 2006
  • For the accurate safety assessment of potential radioactive waste disposal site which is located in the crystalline rock it is important to simulate the mass transportation through engineered and natural barrier system precisely, characterized by porous and fractured media respectively. In this work the methods to construct discrete fracture network for the analysis of flow and mass transport through fractured-porous medium are described. The probability density function is adopted in generating fracture properties for the realistic representation of real fractured rock. In order to investigate the intersection between a porous and a fractured medium described by a 2 dimensional rectangular and a cuboid grid respectively, an additional imaginary fracture is adopted at the face of a porous medium intersected by a fracture. In order to construct large scale flow paths an effective method to find interconnected fractures and algorithms of swift detecting connectivities between fractures or porous medium and fractures are proposed. These methods are expected to contribute to the development of numerical program for the simulation of radioactive nuclide transport through fractured-porous medium from radioactive waste disposal site.

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The Study on the Expression of Vascular Endothelial Adhesion Molecule in Palatine and Pharyngeal Tonsil (구개편도 및 인두편도에서 혈관내피성 접착분자의 발현에 관한 연구)

  • Cho, Jin-Hee;Jang, Han-Sung;Won, Yu-Sung;Lee, Soo-Jin;Yoon, He-Ro;Suh, Byung-Do
    • Korean Journal of Bronchoesophagology
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    • v.5 no.2
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    • pp.174-181
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    • 1999
  • The palatine tonsils(tonsils) and pharyngeal tonsils(adenoids) are situated at the entrance of the respiratory and alimentary tracts and represent the first site of contact with a variety of microorganisms and other antigens present in food and inhaled air. They are known as lymphoid organs carrying out the function of cellular and humoral immunity, and so they form a local protective barrier. And the expression of the vascular endothelial adhesion molecules is known to play an important role for the inflammatory reaction in tonsils and adenoids as well as in other inflammatory tissues, by binding with the receptors on the surface of leukocytes. But although several scientific hypotheses on the role of these lympoid tissues have been suggested, their complete functions have remained unknown. The purpose of this study is to present an basic data of the knowledge on the immunologic physiology of the tonsils and adenoids and their role as active immunologic organs that reinforce the mucosal immunity of the entire upper aerodigestive tract. We examined 16 human tonsils and adenoids and the expression of three endothelial adhesion molecules, vascular endothelial adhesion molecule-1(VCAM-1), intracellular adhesion molecule-1(ICAM-1), and E-selection, in tissue sections using immunohistochemistry. We used the inferior turbinate mucosa obtained from 9 patients getting septal surgery as a control group. The expressions of vascular endothelial adhesion molecule-1(VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) were significantly higher in the tonsils and adenoids. But respectively, there were no significant differences between the tonsils and adenoids. The expression of E-selection was significant higher in the tonsils, but not in the adenoids. We observed that tonsils and adenoids showed significantly higher expressions of vascular endothelial adhesion molecule-1(VCAM-1), intracellular adhesion molecule-1(ICAM-1), and E-selection (in the case of E-selection, only in the tonsils). We propose that these adhesion molecules play an important role for the immunologic reaction by the transendothelial migration of lymphocytes and binding with the receptors on the surface of leukocytes.

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PEP-1-HO-1 prevents MPTP-induced degeneration of dopaminergic neurons in a Parkinson's disease mouse model

  • Youn, Jong Kyu;Kim, Dae Won;Kim, Seung Tae;Park, Sung Yeon;Yeo, Eun Ji;Choi, Yeon Joo;Lee, Hae-Ran;Kim, Duk-Soo;Cho, Sung-Woo;Han, Kyu Hyung;Park, Jinseu;Eum, Won Sik;Hwang, Hyun Sook;Choi, Soo Young
    • BMB Reports
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    • v.47 no.10
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    • pp.569-574
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    • 2014
  • Heme oxygenase-1 (HO-1) degrades heme to carbon dioxide, biliverdin, and $Fe^{2+}$, which play important roles in various biochemical processes. In this study, we examined the protective function of HO-1 against oxidative stress in SH-SY5Y cells and in a Parkinson's disease mouse model. Western blot and fluorescence microscopy analysis demonstrated that PEP-1-HO-1, fused with a PEP-1 peptide can cross the cellular membranes of human neuroblastoma SH-SY5Y cells. In addition, the transduced PEP-1-HO-1 inhibited generation of reactive oxygen species (ROS) and cell death caused by 1-methyl-4-phenylpyridinium ion ($MPP^+$). In contrast, HO-1, which has no ability to transduce into SH-SY5Y cells, failed to reduce $MPP^+$-induced cellular toxicity and ROS production. Furthermore, intraperitoneal injected PEP-1-HO-1 crossed the blood-brain barrier in mouse brains. In a PD mouse model, PEP-1-HO-1 significantly protected against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced toxicity and dopaminergic neuronal death. Therefore, PEP-1-HO-1 could be a useful agent in treating oxidative stress induced ailments including PD.

Phosphatidylserine Enhances Skin Barrier Function Through Keratinocyte Differentiation (포스파티딜세린의 각질세포 분화 유도를 통한 피부장벽 기능 강화)

  • Chung, So-Young;Nam, Sang-June;Choi, Wang-Keun;Seo, Mi-Young;Kim, Jin-Wook;Lee, Seung-Hun;Park, Chang-Seo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.32 no.1 s.55
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    • pp.17-22
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    • 2006
  • Phosphatidyiserine (PS) is a phospholipid which plays the structural role in membranes and serves as a cofactor of signaling enzymes for diverse cellular functions. In this study, we observed that topical treatment with PS significantly decreased trans-epidermal water loss (TEWL) induced by tape-stripping in hairless mice. Also, ceramides in epidermis were increased in PS-treated group compared to vehicle-treated one in vivo. the amounts of non-hydroxyl ceramide (NHCER) (1.4 fold) and glucosylceramide (glucosylCER) (1.6 fold), in the skin of hairless mice, were increased by topical treament with PS. Also, we demonstrated that PS stimulated keratinocyte differentiation. We observed that PS treatment morphologically altered normal human keratinocyte (NHK) from the proliferating phase to the differentiating one, suggesting that PS stimulated epidermal differentiation in NHK. We also showed that the expressions of the specific markers for epidermal differentiation, involucrin (INV) (3.5 fold up) and transglutaminase 1 (TG'ase 1) (3 fold up), were significantly increased by PS treatment, compared to untreated control in vitro. In addition, topical treatment with PS resulted in a progressive increase in INV and loricrin protein levels in vivo. In conclusion, we provide the first evidence for the physiological activities of PS in skin, and we suggest that PS strengthen the epidermal permeability harrier by stimulation of keratinocyte differentiation.