• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.13-16
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• 2003

Adhesion of $SrZrO_3$ resistive oxide barrier on Ag sheathed Bi(2223) tapes prepared by the sol-gel and dip-coating method was evaluated with an aid of Taguchi method and Lie($2^1{\times}3^7$) orthogonal arrays to determine the optimal process combination of levels of factors that best satisfy the bigger is better quality characteristic (QC=B). For analyses of results statistical calculations such as average and analysis of variance (ANOVA) were employed to analyze the results for improving the performance qualities of the dip-coated $SrZrO_3$ film. Experimentally, the performance of the films was evaluated in terms of bond strength by varying Sr/Zr moi ratio (A), amount of organic vehicle additives (B), drying temperature (C) and time (D), heat treatment temperature (E) and time (F), respectively. The optimal combination of levels of factors was determined to be $A_3B_2C_3D_2E_1F_3$ having a 90% confidence level.

• Journal of Pharmaceutical Investigation
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• v.36 no.6
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• pp.393-399
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• 2006

This study was aimed to design, formulate and characterize the moisture-activated patches containing acyclovir for antiviral action. Gel intermediates for film-type patches were prepared with mucoadhesive polymer, viscosity builders, enhancers and acyclovir. Patches containing acyclovir were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane, and of drug flux through the hairless mouse skin. Film-type patches obtained were uniform in the thickness and showed a mucoadhesive property when contacted with moisture. The formulation was optimized, which consisted of $Cantrez^{\circledR}$ AN-169(2%), $Kollidon^{\circledR}$ VA 64(1%), $Natrosol^{\circledR}$(1%), hydroxypropyl-$\beta$-cyclodextrin(1%) and dimethylsulfoxide(0.5%). Release rates of acyclovir patches increased dose-dependently. The addition of terpenes such as d-limonene or cineole increased release rates of acyclovir, but decreased permeation rates. The permeation rates were enhanced by 2 and 2.5 times by the addition of glycyrrhizic acid ammonium salt and sodium glycocholate, respectively, compared with that of no enhancer. These results suggest that it may be feasible to deliver acyclovir through the skin or gingival mucosa from the moisture-activated patches.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06b
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• pp.14-16
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• 2001

The outer membrane (OM) of gram-negative bacteria acts as an effective permeability barrier against noxious agents including several antibiotics and organic solvents, and lipopolysaccharide (LPS) is the key molecule for this function. Outer membrane modified mutants (Ml-166, M2-42, M3-21) of E. coli DH5$\alpha$/pBSl were selected through a mutation using EMS (ethyl-methane-sulfonate). Among the selected mutants, M3-21 was twice as sensitive as LumisTo $x^{ }$ to benzene and M2-41 was 8 times as sensitive as LumisTo $x^{ }$ to toluene. To identify the structural change in the membrane by mutation, the relative cell surface hydrophobicities and the absorption of the crystal violet to the organisms were measured. All the mutants absorbed more crystal violet than their parent and the absorption of crystal violet increased in cell walls as carbohydrate of lipopolysaccharide decreased. When the cell surface hydrophobicities of DH5/pBSl and its mutants were measured by the BATH, the hydrophobicities of mutants increased compared to their parent in several organic solvents. The difference of lipopolysaccharide between DH5/pBSl and its mutants was identified by various ways such as the SDS-PAGE gel, the screening of LPS molecular weights, the mass spectrometry, and MALDI-TOF.F.

• Natural Product Sciences
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• v.26 no.2
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• pp.158-164
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• 2020

Helicobacter pylori is a well-known pathogen that is responsible for gastric disorders. Overcoming of the antibiotic-resistance is a main barrier to treat H. pylori infection. In our search for anti-H. pylori compounds from natural resources, bioactivity-guided isolation on the ethyl acetate fraction of Fraxinus mandshurica bark that had shown anti-H. pylori activity gave twelve compounds (1 - 12) of six coumarins, three phenylethanoids, two secoiridoids, and a lignan using silica gel column chromatography, Sephadex-LH 20, and recrystallization. The chemical structures were identified by spectroscopic data analysis, including 1D, 2D NMR, and mass spectrometry. Among them, compounds 2, 10, and 11 showed moderate growth inhibitory activity against three strains of H. pylori, compared with positive controls of quercetin and metronidazole. Compounds 5, 6, 8, and 12 exhibited the inhibitory activity against strains 26695 or 43504. This is the first report on the anti-H. pylori activity of this plant and the isolated compounds.

• Molecules and Cells
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• v.39 no.9
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• pp.687-691
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• 2016

Transcription activator-like effector nucleases (TALENs) are powerful tools for targeted genome editing in diverse cell types and organisms. However, the highly identical TALE repeat sequences make it challenging to assemble TALEs using conventional cloning approaches, and multiple repeats in one plasmid are easily catalyzed for homologous recombination in bacteria. Although the methods for TALE assembly are constantly improving, these methods are not convenient because of laborious assembly steps or large module libraries, limiting their broad utility. To overcome the barrier of multiple assembly steps, we report a one-step system for the convenient and flexible assembly of a 180 TALE module library. This study is the first demonstration to ligate 9 mono-/dimer modules and one circular TALEN backbone vector in a one step process, generating 9.5 to 18.5 repeat sequences with an overall assembly rate higher than 50%. This system makes TALEN assembly much simpler than the conventional cloning of two DNA fragments because this strategy combines digestion and ligation into one step using circular vectors and different modules to avoid gel extraction. Therefore, this system provides a convenient tool for the application of TALEN-mediated genome editing in scientific studies and clinical trials.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.217-234
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• 1997

The purpose of present study is to compare the effect of treatment using $Guidor^{(R)}$ as a barrier membrane in conjunction with platelet-derived growth factor and insulin like growth factors on experimental dehiscence defects. Following the resection of premolar crowns, roots were submerged. After 12 weeks of healing period, experimental dehiscence defects of 4mm in height and 4mm in width were surgically created on the mid-facial aspect of the lower premolar roots in each of 4 adult dogs. After root planning and demineralization of the root surface with citric acid, the control groups received 4% methylcellulose gel only, the test group I received 4% methylcellulose gel and were covered by $Guidor^{(R)}$ and the test group II were treated with PDGF and IGF and 4% methylcellulose gel with $Guidor^{(R)}$ coverage. Histological and histomorphometric analysis following 8 weeks of healing revealed the following results. 1. The new bone formation showed no statistically significant difference in all groups with $0.59{\pm}0.82mm$($14.03{\pm}19.60%$) for control, $0.70{\pm}0.39mm$($16.30{\pm}9.01%$) for group I, $0.87{\pm}0.76mm$($18.74{\pm}16.03%$) for group II. 2. The new cementum formation showed no statistically significant difference in all groups with $0.54{\pm}0.48mm$($l6.38{\pm}14.57%$) for control, $0.95{\pm}0.38mm$($23.43{\pm}9.30%$) for group I, $1.01{\pm}0.75mm$($22.10{\pm}16.ll%$) for gorup II. 3. The root resorption showed statistically significant differences betweenthe control group and all test groups(p<0.05) with $2.11{\pm}0.53mm$($52.93{\pm}12.32%$) for control, $0.63{\pm}0.27mm$($15.32{\pm}7.05%$) for group I, $0.89{\pm}0.33mm$ ($19.26{\pm}7.11%$) for group II. On the bases of these results, there were no statistically difference between treatment using resorbable membrane and resorbable membrane in conjunction with PDGF and IGF in the dehiscence defects, where it was difficult to maintain space. The use of membrane seemed to be more effective in the inhibition of root resorption.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.669-683
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• 2017

The objective of this study is to propose a modification of the previously proposed drainage system for catching the partial leakage of underground concrete structures. Two techniques were proposed for applying the drainage system only to the leaking parts. One was for conveying leaking groundwater to the collection point in the drainage system and the other was for conveying the collected groundwater to the primary drainage system of the underground concrete structure. Four waterproofing materials for conveying leaking groundwater to the catchment point of the drainage system, Durkflex made of porous rubber material, KE-45 silicone adhesive with super strong adhesion, Hotty-gel made of polymeric materials and general silicone adhesive were evaluated for waterproofing performance. Hotty-gel only showed perfect waterproof performance and the other three waterproof materials leaked. The modified drainage system with Hotty-gel and drainage pipe with fixed saddle to convey the leaking groundwater from the catchment point to the primary drainage system were tested on the concrete retaining wall. The waterproof performance and the drainage performance were evaluated by injecting 1,000 ml of water in the back of the modified drainage system at the 7-day, 14-day, 21-day, 28-day, 2-month and 3-month. There was no problem in waterproof performance and drainage performance of the modified drainage system during 3 months. In order to evaluate the construction period and construction cost of the modified drainage system, it was compared with the existing leaching repair method in surface cleaning stage, leakage treatment stage, and protective barrier stage. Total construction period and construction cost were compared in considering the contents of work, repair material, construction equipment, working time, and total number of workers. As a result of comparing and analyzing in each construction stage, it was concluded that the modified drainage system could save construction period and construction cost compared to the existing leaching repair method.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.365-376
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• 2006

The purpose of this study was to evaluate the efficacy of blocking the oxygen in the air during the polymerization of sealant. All curing were performed with various light curing units under the application of oxygen gel barrier, stream of nitrogen and carbon dioxide gas for inhibition of oxygen diffusion into sealant surface. The results of present study can be summarized as follows : 1. The amount of eluted TEGDMA form the specimens cured with all the three different light units in the stream of $N_2$ and $CO_2$ gas and application of Oxygen gel barrier($DeOx^{(R)}$) were significantly lower than in the room-air atmosphere (Control) (p<0.05). 2. In the $DeOx^{(R)}$ application, the amount of eluted TEGDMA the specimen cured with PAC light for 10seconds was less than that cured in the stream of $N_2$ and $CO_2$ atmospheric conditions (p<0.05) 3. In the LED using 10 or 20sec irradiation times under the stream of $N_2$ and $CO_2$, the eluted TEGDMA showed to be no statistically significant difference (p>0.05). 4. The microhardness from the specimens cured with all the three different light units under each treated conditions were significantly higher than in the room-air atmosphere (p<0.05). 5. The surface treatment by $DeOx^{(R)}$, $N_2$ and $CO_2$ reduces the thickness of oxygen inhibited layer by sp proximately 49% of the untreated control value.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.345-352
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• 2004

There are two paradigms to explain the atopic dermatitis. The first is outside-inside paradigm and the second is inside-outside paradigm. According to the outside-inside paradigm the best way to treat the atopic dermatitis is recovery of skin barrier function. The barrier function is maintained by the specific structure of stratum corneum, which is constructed from corneocytes and intercellular lipids. In terms of lipid structures of SC in atopic dermatitis and lamellar ichthyosis, they contain more fluid hexagonal gel structures in SC and show deficiencies in free fatty acids, especially long chains and certain ceramides. With this reason, moisturizer which has the lamellar structure and restoring function of intrinsic intercellualr long periodicity phase can maintain and restore the lamellar structure of intercellular lipids in SC. The moisturizers containing ceramide or pseudoceramide also seem to be reasonable therapy for atopic dermatitis and several skin diseases, which interrelated with impaired skin harrier. By the way, according to the inside-outside paradigm, immune response including helper T cells, IgE, eosinophils is related. It is effective treatment of atopic dermititis to restore imbalance between Th1 and Th2 cells. Even though several kinds of immune-suppressor were introduced, these can affect the intrinsic immune function. SPC and S1P, metabolites of ceramide, would be interesting because they have the function of wound healing and immune modulating properties.

• Journal of the Korean Magnetics Society
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• v.12 no.2
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• pp.41-45
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• 2002

The low-field tunnel-type magnetoresistance (MR) properties of sol-gel derived $La_{0.7}Pb_{0.3}MnO_3(LPMO)$ thin film deposited on different substrate have been investigated. Polycrystalline thin films were fabricated by spin-coating on $SiO_2/Si(100)$ substrate and that with yttria-stabilized zirconia (YSZ) buffer layer, while c-axis-oriented thim film was grown on $LaAlO_3(001)$ (LAO) single crystal substrate. The full width half maximum (FWHM) of the rocking curve scan of LPMO/LAO film is $0.32^{\circ}$. Tunnel-type MR ratio is 0.52 % in $LPMO/SiO_2/Si$(100) film and that of $LPMO/YSZ/SiO_2/Si$(100) film is as high as 0.68 %, whereas that of LPMO/LAO(001) film is less than 0.4 % under the applied field of 500 Oe at 300 K. Well-pronounced MR hysteresis was registered with an MR peak in the vicinity of the coercive field. The low-field tunnel-type MR characteristics of thin films deposited on different substrates originates from the behavior of grain boundary properties.