• Title/Summary/Keyword: Barrier Potential

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Breast abscess caused by Staphylococcus aureus in 2 adolescent girls with atopic dermatitis

  • Park, Sung Man;Choi, Won Sik;Yoon, YoonSun;Jung, Gee Hae;Lee, Chang Kyu;Ahn, So Hyun;Yoon, Wonsuck;Yoo, Young
    • Clinical and Experimental Pediatrics
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    • v.61 no.6
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    • pp.200-204
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    • 2018
  • Atopic dermatitis (AD) is a chronic inflammatory skin disease in children. Patients with AD experience a high rate of colonization of the skin surface by Staphylococcus aureus. Because of a skin barrier defect, there is a potential risk of staphylococcal invasive infection in patients with AD. Here, we present 2 cases of breast abscess caused by S. aureus in 2 adolescent girls with severe AD. Methicillin-sensitive S. aureus was identified from the breast abscess material. They were treated with appropriate antibiotics, however surgical drainage of the abscess was needed in case 1. Identical strains were found from the breast abscess material as well as the lesional and the nonlesional skin of the patients through matrix-assisted laser desorption/ionization time-of-flight analysis. We characterized the differential abundance of Firmicutes phylum in patients' skin in microbiota analysis. In particular, S. aureus, a member of Firmicutes, differed significantly between the lesional and the normal-appearing skin. Our cases demonstrate the potential severity of bacterial deep tissue infection in AD and the dysbiosis of skin microbiota may be involved in inflammation in AD.

The Duration of Punctuated Equilibria in Simple Genetic Algorithms (단순 유전 알고리즘에서 단속평형의 지속시간에 대한 연구)

  • Oh, Sang-Yeop
    • Journal of KIISE:Software and Applications
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    • v.32 no.11
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    • pp.1059-1070
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    • 2005
  • For genetic algorithms, the population may get stuck in a local optimum. The population can escape from this after a long duration. This phenomenon is called punctuated equilibrium. The punctuated equilibria observed in nature and computational ecosystems are known to be well described by diffusion equations. In this paper, simple genetic algorithms are theoretically analyzed to show that they can also be described by a diffusion equation. When fitness is the function of unitation, this analysis can be further refined to make the parameters of genetic algorithms appear in this equation. Using theoretical results on the diffusion equation, the duration of equilibrium is shown to be exponential of such parameters as population size, 1/(mutation probability), and potential barrier. This is corroborated by simulation results for bistable potential landscapes with one local optimum and one global optimum.

Effect of Neutral Salts on the Reactive Dyeing of Silk (Ⅱ) - Effect of Anions - (중성염이 견의 반응염색에 미치는 영향 (Ⅱ) - 음이온의 영향 -)

  • Do, Seong Guk;Park, Chan Heon;Gwon, Ji Yun
    • Textile Coloration and Finishing
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    • v.13 no.2
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    • pp.28-28
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    • 2001
  • Four kinds of neutral sodium salts with different anions, NaF, NaCl, NaBr, and NaI, were added to the dye bath to accurately understand the effect of anions on the reactive dyeing of silk with C. I. Reactive Black 5. The sodium cation lowered the negative surface potential of the silk and increased the dye-uptake on fille fabric as reported previously. However, because of the discrepancy in the anions′inhibition power from cation′s lowering the surface negative potential the amount of the dye on the silk fiber was different from each other in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$. The activation energy($E_a$) for the dyeing was in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ but the dye-uptake on the fabric and the activation free energy(Δ$G^*$), the real energy barrier for the reaction, were in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ because the strength of the interaction of the anions with sodium cations was the same as the order of the latter. In other words $F^-$ exerted the weakest electrostatic force on $Na^+$and competed with the dyestuff anions least of all. The decrease in Δ$S^*$may be due to the looesly bonded activated complex of dyestuff anions, sodium cations and fiber molecules at transition state. It was clarified from the Bronsted equation that sodium salts with different anions also had fille ionic strength effect and the specific salt effect on the reactive dyeing.

The biological effect of cyanoacrylate-combined calcium phosphate in rabbit calvarial defects

  • Chang, Yun-Young;Dissanayake, Surangi;Yun, Jeong-Ho;Jung, Ui-Won;Kim, Chang-Sung;Park, Kyeong-Jun;Chai, Jung-Kiu;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.41 no.3
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    • pp.123-130
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    • 2011
  • Purpose: The purpose of this study was to determine the biological effects of cyanoacrylate-combined calcium phosphate (CCP), in particular its potential to act as a physical barrier - functioning like a membrane - in rabbit calvarial defects. Methods: In each animal, four circular calvarial defects with a diameter of 8 mm were prepared and then filled with either nothing (control group) or one of three different experimental materials. In the experimental conditions, they were filled with CCP alone (CCP group), filled with biphasic calcium phosphate (BCP) and then covered with an absorbable collagen sponge (ACS; BCP/ACS group), or filled with BCP and then covered by CCP (BCP/CCP group). Results: After 4 and 8 weeks of healing, new bone formation appeared to be lower in the CCP group than in the control group, but the difference was not statistically significant. In both the CCP and BCP/CCP groups, inflammatory cells could be seen after 4 and 8 weeks of healing. Conclusions: Within the limits of this study, CCP exhibited limited osteoconductivity in rabbit calvarial defects and was histologically associated with the presence of inflammatory cells. However, CCP demonstrated its ability to stabilize graft particles and its potential as an effective defect filler in bone augmentation, if the biocompatibility and osteoconductivity of CCP were improved.

Photoprotective effects of topical ginseng leaf extract using Ultraflo L against UVB-induced skin damage in hairless mice

  • Hong, Yang Hee;Lee, Hyun-Sun;Jung, Eun Young;Han, Sung-Hee;Park, Yooheon;Suh, Hyung Joo
    • Journal of Ginseng Research
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    • v.41 no.4
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    • pp.456-462
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    • 2017
  • Background: Abnormal activation of matrix metalloproteinases (MMPs) plays an important role in UV-induced wrinkle formation, which is a major dermatological problem. This formation occurs due to the degeneration of the extracellular matrix (ECM). In this study, we investigated the cutaneous photoprotective effects of Ultraflo L treated ginseng leaf (UTGL) in hairless mice. Methods: SKH-1 hairless mice (6 weeks of age) were randomly divided into four groups (8 mice/group). UTGL formulation was applied topically to the skin of the mice for 10 weeks. The normal control group received nonvehicle and was not irradiated with UVB. The UV control (UVB) group received nonvehicle and was exposed to gradient-UVB irradiation. The groups (GA) receiving topical application of UTGL formulation were subjected to gradient-UVB irradiation on $0.5mg/cm^2$ [GA-low (GA-L)] and $1.0mg/cm^2$ [(GA-high (GA-H)] of dorsal skin area, respectively. Results: We found that topical treatment with UTGL attenuated UVB-induced epidermal thickness and impairment of skin barrier function. Additionally, UTGL suppressed the expression of MMP-2, -3, and -13 induced by UVB irradiation. Our results show that topical application of UTGL protects the skin against UVB-induced damage in hairless mice and suggest that UTGL can act as a potential agent for preventing and/or treating UVB-induced photoaging. Conclusion: UTGL possesses sunscreen properties and may exhibit photochemoprotective activities inside the skin of mice. Therefore, UTGL could be used as a potential therapeutic agent to protect the skin against UVB-induced photoaging.

Study on the Prescribed Doses and Dispensing Patterns of Warfarin and Digoxin Tablets (Warfarin 및 Digoxin 정제의 처방 용량 실태 및 조제 양식의 고찰)

  • Kim, Yoonsook;Lee, Seungmi;Chun, Pusoon
    • YAKHAK HOEJI
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    • v.58 no.1
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    • pp.40-46
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    • 2014
  • Drugs with a narrow therapeutic index (NTI) require very precise dosing. Warfarin and digoxin are the examples of NTI-drugs and dosing of them varies widely for different patients. However, in South Korea, only two strengths of warfarin and one of digoxin are commercially available. This is a big barrier for the precise dispensing and has potential safety risks to patients, particularly to elderly patients. To find a potential solution to the problem, an analysis of the prescribed doses and dispensing patterns of those drugs was performed. Data were collected by computer-facilitated prescription review in a university hospital. The period screened was from May 1st, 2012 to April 30th, 2013. All the prescriptions with either warfarin or digoxin tablets were selected for this study and dispensing patterns were analyzed according to the prescribed doses. A total of 17,017 warfarin prescriptions were analyzed; 8,148 for inpatient prescriptions, 8,869 for outpatient prescriptions, respectively. Of the 23 kinds of prescribed doses, 2 mg (19.9%) was most frequent, followed by 3 mg (13.2%) and 2.5 mg (11.7%). By analyzing the dispensing patterns, 60.3% (10,253) of the prescriptions required pill splitting and 72.0% of them were for the patients 65 years old and over. On the other hand, 4,350 digoxin prescriptions were included in this study. Of the 6 kinds of prescribed doses, 0.125 mg (71.2%) was most frequent, followed by 0.0625 mg (20.2%). Among the prescriptions for digoxin, 92.0% (3,998) should be split and 65.7% of them were for the patients aged 65 years and over. Despite limitations of strengths, various doses of warfarin and digoxin were prescribed. Furthermore, more than half of the prescriptions that required pill splitting were for elderly patients. The results from this study suggest that different strengths of warfarin and digoxin should be provided for accuracy of dispensing and safety for patients receiving them.

Network pharmacological analysis for identifying herbal medicine candidate for cerebral infarction focusing on Gardeniae Fructus (뇌경색 전임상 연구 후보 약재 선정을 위한 네트워크 약리학 분석법의 활용과 치자(梔子)의 적용 가능성 검토)

  • Jung Joohyun;Park Heejun;Lim Sehyun;Cho Suin
    • Herbal Formula Science
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    • v.31 no.3
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    • pp.145-156
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    • 2023
  • Objectives : This study aimed to select candidate herbal medicines to be used in preclinical studies of cerebral infarction using the network pharmacology research method. Methods : Oral bioavailability (OB), drug likeness (DL), Caco-2, and blood-brain barrier (BBB) permeability were employed in this study's network pharmacology analysis method to choose compounds with potential efficacy. The following formulas were utilized for the values of each variable used in this study: OB ≥ 20%, DL ≥ 0.18, Caco-2 ≥ 0, and BBB ≥ -0.3. The relationships between target proteins and diseases that are assumed to be involved in the chosen bioavailable chemicals were built in a network manner using the aforementioned factors, and proteins thought to play a significant role were identified. Results : Sudan III was obtained as a result of selecting compounds related to ischemic stroke in consideration of pharmacokinetic characteristics such as digestion and absorption and practicality using the TCMSP database. Medicinal herbs Gardeniae Fructus (GF) contains sudan III, and it was confirmed that compounds in GF were highly related to brain diseases, and the mechanism involved through the KEGG pathway was confirmed. GF, which has sudan III related to ischemic stroke and is also involved in other neurological diseases, is expected to be used for ischemic stroke treatment. Conclusions : GF has been predicted to have potential for ischemic stroke treatment, and can be used for future preclinical studies.

Establishing porcine jejunum-derived intestinal organoids to study the function of intestinal epithelium as an alternative for animal testing

  • Bo Ram Lee;Sun A Ock;Mi Ryung Park;Min Gook Lee;Sung June Byun
    • Journal of Animal Reproduction and Biotechnology
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    • v.39 no.1
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    • pp.2-11
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    • 2024
  • Background: The small intestine plays a crucial role in animals in maintaining homeostasis as well as a series of physiological events such as nutrient uptake and immune function to improve productivity. Research on intestinal organoids has recently garnered interest, aiming to study various functions of the intestinal epithelium as a potential alternative to an in vivo system. These technologies have created new possibilities and opportunities for substituting animals for testing with an in vitro model. Methods: Here, we report the establishment and characterisation of intestinal organoids derived from jejunum tissues of adult pigs. Intestinal crypts, including intestinal stem cells from the jejunum tissue of adult pigs (10 months old), were sequentially isolated and cultivated over several passages without losing their proliferation and differentiation using the scaffold-based and three-dimensional method, which indicated the recapitulating capacity. Results: Porcine jejunum-derived intestinal organoids showed the specific expression of several genes related to intestinal stem cells and the epithelium. Furthermore, they showed high permeability when exposed to FITC-dextran 4 kDa, representing a barrier function similar to that of in vivo tissues. Collectively, these results demonstrate the efficient cultivation and characteristics of porcine jejunum-derived intestinal organoids. Conclusions: In this study, using a 3D culture system, we successfully established porcine jejunum-derived intestinal organoids. They show potential for various applications, such as for nutrient absorption as an in vitro model of the intestinal epithelium fused with organ-on-a-chip technology to improve productivity in animal biotechnology in future studies.

Growth and Structural Properties of Fe Thin Films Electrodeposited on n-Si(111) (n-Si(111) 기판 위에 전기증착에 의한 Fe 박막의 성장과 구조적 특성)

  • Kim Hyun-Deok;Park Kyeong-Won;Lee Jong-Duk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.9
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    • pp.1663-1670
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    • 2006
  • Single crystal Fe thin films were grown directly onto n-Si(111) substrates by pulsed electrodeposition. Cyclic Voltammogram(CV) indicated that the $Fe^{2+}/n-Si(111)$ interface shows a good diode behavior by forming a Schottky barrier. From Mott-Schottky (MS) relation, it is found that the flat-band potential of n-Si(111) substrate and equilibrium redox potential of $Fet^{2+}$ ions are -0.526V and -0.316V, respectively. The nucleation and growth kinetics at the initial reaction stages of Fe/n-Si(111) substraste was studied by current transients. Current transients measurements have indicated that the deposition process starts via instantaneous nucleation and 3D diffusion limited growth. After the more deposition, the deposition flux of Fe ions was saturated with increase of deposition time. from the as-deposited sample obtained using the potential pulse of 1.4V and 300Hz, it is found that Fe nuclei grows to three dimensional(3D) islands with the average size of about 100nm in early deposition stages. As the deposition time increases, the sizes of Fe nuclei increases progressively and by a coalescence of the nuclei, a continuous Fe films grow on the Si surface. In this case, the Fe films show a highly oriented columnar structure and x-ray diffraction patterns reveal that the phase ${\alpha}-Fe$ grows on the n-Si(111) substrates.

A Study on Trade Structure Analysis between Korea and GCC(Gulf Cooperation Council) Countries (한국과 걸프협력회의(GCC)국가 간의 교역구조분석에 관한 연구)

  • Chung, Tae-Won
    • Journal of Digital Convergence
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    • v.14 no.11
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    • pp.135-142
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    • 2016
  • Although growth potential of trade between Korea and the GCC region has existed in various fields through economic and business cooperation, few data and practical study related with trade structure and cooperation between Korea and GCC region have been found and the potential for further economic expansion has not been extensively explored. In this sense, this study is to analyze trade flows between Korea and GCC region countries(Saudi Arabia, Unites Arab Emirates, Qatar) using trade intensity index, trade complementarity index and special country bias index, identify potential for further expansion of Korea's trade into the GCC region and further propose the implication of FTA between mutual countries. Our analysis of trade flows also demonstrates that there is a high level of trade complementarity between Korea and GCC region. It means that increase of trade complementarity and special country bias come from removing not only trade barrier and increasing but also capital movement. Especially, the study reveals that there is an untapped potential for Korea to increase its exports to Saudi, based on the highest complementarities. Export expansion between Korea and Saudi through FTA will create new opportunity in near future.