• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.116-122
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• 2000

On the instrumented root canal wall, amorphous, irregular smear layer can be observed with Scanning Electron Microscope(SEM). The purpose of this study was to evaluate the effect of the presence or absence of smear layer on the adhesion of Staphylococcus aureus to the dentin of the root canal. Human incisors, extracted within 7 days, with no caries, no fracture, no calcification of canal, were selected. After cutting crown portion at cemento-enamel junction, root canal preparation was done by modified crown-down technique using Profile and Gates - Glidden Drill. During canal preparation, 10ml physiologic saline solution(group1&3) or 10ml 3.5% NaOCl(group2&4) was used as irrigation solution. And 10ml physiologic saline solution(group1&3) or 10ml 0.5M EDTA(group2&4) was applicated for final flush. After vertical sectioning and ethylene oxide gas sterilization, samples(group1&2) were immersed into BHIYHM broth inoculated with Staphylococcus aureus (ATCC 31153) and incubated for 3hrs at $37^{\circ}C$. All samples were prepared for and observed with SEM(JEOL JSM840S). The data were analyzed by Mann-Whitney rank sum test. The conclusions are as follows ; 1. Smear layer covers entire root canal surface after root canal preparation. 2. Smear layer has been removed away and the entrances of dentinal tubules have opened widely, when applying 0.5M EDTA and 3.5% NaOCl. 3. A significantly higher number of bacteria were adhered to the root canal dentin without smear layer(p<0.0001). 4. Smear layer produced during root canal preparation impedes bacterial adhesion and colonization to dentin matrix, therefore inhibits canal reinfection.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.379-386
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• 2004

Jeung-Pyun is a traditional Korean fermented rice cake leavened by yeast. To develop a functional Jeung-Pyun, mulberry leaf(ML) were added to the rice at the levels of 0, 2, 4, 6, 8%, respectively. Physicochemical, sensory, texture and surface characteristics of Jeung-Pyun were examined. The specific volumes of all the Jeung-Pyun's with ML were significantly lower than that of control(0% ML) and 4% ML sample showed the highest volume among them. The pH of ML Jeung-Pyun batters decreased with fermentation time. Overall quality of Jeung-Pyun with ML obtained lower value than the control. Among the texture properties measured with rheometer, hardness, cohesiveness, gumminess and brittleness of ML Jeung-Pyun decreased according to the amount ML added and springiness was not significantly different. The surface structure by SEM showed that Jeung-Pyun added with 4% ML had the largest and the most uniform air cells. In conclusion, the most acceptable concentrations of ML on the basis of overall quality in sensory evaluation and physicochemical characteristics were 2% or 4%.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1205-1209
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• 2000

The present study was undertaken to investigate the effect of stimulation of follicular development with eCG on the peripheral levels of inhibin and FSH in Murrah buffaloes. Estrus was synchronized in five normally cycling females by insertion of Crestar (Intervet, Boxmeer, Holland) implants for nine days. Estradiol valerate was administered i.m. on the day of implant insertion. On the 10th day of the induced estrous cycle a single dose of 3000 IU eCG (Folligon, Intervet, Boxmeer, Holland) was given, followed by treatment with 25 mg of $PGF_2$ alpha (Lutalyse, Upjohn, Belgium) 48 h later. Blood samples were obtained during the induced estrus, on cycle day 10 (luteal phase), at the superovulatory estrus (43 h after PGF) and during the periovulatory period (64 h after PGF). Ultrasonography was done daily to monitor follicular development. Plasma concentrations of inhibin and FSH were determined by specific radioimmunoassays. Differences between $mean{\pm}SEM$ values of different phases of the cycle were compared by ANOVA. The mean number of small (2-5 mm), medium (6-9 mm) and large (>10 mm) follicles observed two days after eCG treatment and on the day of superovulatory estrus was $2.8{\pm}0.31$, $5.2{\pm}0.30$ and $1.4{\pm}0.09$ and $1.9{\pm}0.21$, $2.8{\pm}0.40$ and $5.0{\pm}0.83$, respectively. The mean number of ovulations was $3.6{\pm}0.37$ and the mean number of unovulated follicles was $6.1{\pm}0.47$. Most of the follicles >10 mm in diameter had ovulated (72%). The mean ${\pm}SEM $ of plasma inhibin concentration $(2584.15{\pm}17.92pg/ml)$ during the superovulatory estrus was significantly higher $(p{\leq}0.05)$ than during the induced estrus $(749.87{\pm}17.29pg/ml)$, the luteal phase $(1099.54{\pm}24.98pg/ml)$ and periovulatory period $(1682.71{\pm}29.88pg/ml)$, respectively. $Mean{\pm}SEM$ plasma FSH concentration during the induced estrus $(10.35{\pm}0.41ng/ml)$ was not different from that during the superovulatory estrus $(8.52{\pm}0.39ng/ml)$, but was significantly higher $(p{\leq}0.05)$ than during the luteal phase $(2.81{\pm}0.42ng/ml)$ and periovulatory period $(5.7{\pm}0.28ng/ml)$. These data indicate that treatment with eCG in buffaloes for inducing superovulation results in a significant elevation in plasma inhibin levels and a decrease in plasma FSH levels during the superovulatory estrus. Thus, we suggest that the elevated plasma inhibin coming from fully developed follicles continued for a long time which results in inhibition of FSH leading to poor ovulation in the remaining follicles, which may be the cause of suboptimal superovulatory response.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.247-252
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• 1997

Perfluorotolyl (PFT)-ether and perfluorotoly-trimethylsilyl (PFT-TMS) ether derivatives of oestrone, $17{\alpha}$- and $17{\beta}$oestradiol were prepared under phase transfer conditons. The former derivatives under negative ion chemical ionization conditions gave significant ions in the mass spectrometer but $17{\alpha}$- and $17{\beta}$ -oestradiol gave poor resolution. However, the PFT-TMS derivatives of 17.${\alpha}$- and$17{\beta}$-oestradiol showed good resolution. These derivatives were used for the analysis of oestrogens in bovine aqueous humour, vitreous humour and retina. The mean $({\pm}SEM)$ concentrations of oestrone in bovine aqueous humour (n=18), vitreous humour (n=18) and bovine retina (n=4) were $0.47{\pm}0.11$, $0.46{\pm}0.14$ and $1.10{\pm}0.24 ng.ml^{-1}$, respectively. $17{\alpha}$-Oestradiol was detected in 16 out of 18 samples of bovine aqueous humour and vitreous humour and the mean $({\pm}SEM)$ concentrations were $0.30{\pm}0.10$ and $0.08{\pm}0.02 ng.ml^{-1}$, respectively. The mean $({\pm}SEM)$ concentration of 17.betha.-oestradiol in aqueous humour (n=7) and vitreous homour (n=11) $0.83{\pm}0.26 ng ml^{-1}$ and $0.39{\pm}0.09 ng ml^-1$, respectively. In retina the concentrations of both steroids were below the detection limit.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.154-160
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• 1986

In order to develope interspecific fusion of the genus Cellulomonas capable of assimilation cellulose, the optimun conditions for the protoplast formation was investigated to examine the susceptibility of cell wall, between different species of the same genus using scanning electron microscope. The variation in the susceptibilities of Cellulomonas sp. CS 1-1 and C. flavigena to lysozyme treatment were considerably remarkable, although they belong to the same genus. The rate of protoplast formation of CS1-1 was 99.9% being treated with lysozyme $(100{\mu}g/ml)$ for 30 minute and that of C. flavigena was about 80% being treated at the concentration of $600{\mu}g/ml$ of lysozyme for 6 hours. The susceptibility of cell wall to the lysozyme treatment on protoplast formation of the strain, CS1-1 seems not to be depend on the cultural periods of cells. On the contrary, that of C. flavigena was considerably depend on the periods. Cells of C. flavigena at mid exponential phase could be more efficiently converted to protoplast cells than those at late exponential phase be done. The rate of the protoplast formation was 95%, when cells of C. flavigena at mid exponential phase were treated with lysozyme $600{\mu}g/ml$ for 6 hours and observed by SEM. In the evalution of protoplast formation of the CS1-1 results of counting method in plate after osmotic shock treatment were similar to the results of the direct observation method by means of SEM. But in the case of C. flavigena the latter method was much more reliable than the former, because the differences between the number of spheroplasts and protoplasts were not able to figure out on conuting the number of protoplast after osmotic shock tretment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.582-590
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• 1987

Plasteins were synthesized from a peptic filefish protein hydrolysate by papain, $\alpha-chymotrypsin$ and protease(from Streptomyces griceus) under the optimum conditions of previous paper. L-glutamic acid diethylester and L-leucine ethylester were incorporated into plastein during the plastein reaction by papain. The structural changes of freeze-dried filefish meat, peptic hydrolysate, FPC and plasteins were observed by Scanning Electron Microscopy(SEM). The functional properties of plasteins also were measured. The solubility of plasteins was higher than that of FPC and the Glu-plastein had $95\%$ solubility in the range of pH 3-10. The dispersibility of Glu-plastein and protease plastein was similar to that of egg albumin, but those of the other plasteins were lower. The water holding capacity of plasteins was lower than that of egg albumin and C. Lipid absorption of Leu-plastein was tile highest, holding 1.80 ml/g, and that of the other plasteins was similar to that of egg albumin. The emulsifying activity of Leu-plastein was the highest, holding $61.2\%$, and that of Glu-plastein was the lowest, holding $50.7\%$. The emulsifying stability of plasteins was similar to that of the emulsifying activity. The emulsifying capacity of Leu-plastein was 384 ml/g(the highest), but that of Glu-plastein and $\alpha-chymotrypsin$ plastein was 248 ml/g(the lowest). The Leu-plastein shelved the highest foaming capacity, $373\%$. The foaming capacity of other plasteins was higher than that of egg albumin. The foaming stability of plasteins was superior to that of egg albumin. The viscosity of plasteins was lower than that of egg albumin. The microstructure of $\alpha-chymotrypsin$ plastein by SEM wassimilar to that of papain plastein, but other plasteins showed differences in their microstructure. The microstructure of Glu-plastein had a smooth shape.

• Journal of Haehwa Medicine
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• v.5 no.2
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• pp.523-533
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• 1997

Ursolic acid(UA) was isolated from Oldenlandiae diffusae Herba, one of the commonly used medicinal herbs for the treatment of cancer. IC50 of UA against cancer cell lines as SNU-1, B16-Fo. SK-OV3, HCT15, XF498, SK-MEL and A549 was $6{\mu}g/ml$, 4$4.4{\mu}g/ml$, $4.5{\mu}g/ml$, $4.6{\mu}g/ml$ and $4.2{\mu}g/ml$ respectively suggesting cytotoxicity against cancer cells. DNA fragmentation was expressed from the concnetration of $5.5{\mu}g/ml$ of UA by agarose electrphoresis. In the observation of morphological changes by phase contrast microscope, SEM and TEM, cell injury and condensation of cytoplasm from nucleus began 4 hr after UA treatment. fragmentaion of nucleus and injury of cell membrane was shown 24 hr after UA treatmeilt with SNU-1 cells. Aurin tricarboxic acid as endonuclease inhibitor. and nicotinamide as poly(ADP-ribose) polymerase inhibitor protected over 50% of cytotoxicity of UA against SNU-1 was at the concentrations of $3{\mu}M$ and $300{\mu}M$ respectively suggesting UA acts on nucleus. These results suggest that UA had antimetastatic effect and induced apoptosis.

• Korean Journal of Materials Research
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• v.22 no.6
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• pp.275-279
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• 2012

(3-mercaptopropyl)trimethoxysilane (MPTMS) was used as a silylation agent, and modified silica nanoparticles were prepared by solution polymerization. 2.0 g of silica nanoparticles, 150 ml of toluene, and 20 ml of MPTMS were put into a 300 ml flask, and these mixtures were dispersed with ultrasonic vibration for 60 min. 0.2 g of hydroquinone as an inhibitor and 1 to 2 drops of 2,6-dimethylpyridine as a catalyst were added into the mixture. The mixture was then stirred with a magnetic stirrer for 8 hrs. at room temperature. After the reaction, the mixture was centrifuged for 1 hr. at 6000rpm. After precipitation, 150 ml of ethanol was added, and ultrasonic vibration was applied for 30 min. After the ultrasonic vibration, centrifugation was carried out again for 1 hr. at 6000rpm. Organo-modification of silica nanoparticles with a ${\gamma}$-methacryloxypropyl functional group was successfully achieved by solution polymerization in the ethanol solution. The characteristics of the ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) were examined using X-ray photoelectron spectroscopy (XPS, THERMO VG SCIENTIFIC, MultiLab 2000), a laser scattering system (LSS, TOPCON Co., GLS-1000), Fourier transform infrared spectroscopy (FTIR, JASCO INTERNATIONL CO., FT/IR-4200), scanning electron microscopy (SEM, HITACHI, S-2400), an elemental analysis (EA, Elementar, Vario macro/micro) and a thermogravimetric analysis (TGA, Perkin Elmer, TGA 7, Pyris 1). From the analysis results, the content of the methacryloxypropyl group was 0.98 mmol/g and the conversion rate of acrylamide monomer was 93%. SEM analysis results showed that the organo-modification of ultra-fine particles effectively prevented their agglomeration and improved their dispensability.

• Fashion & Textile Research Journal
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• v.22 no.2
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• pp.233-239
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• 2020

We proposed a simple process of fabricating electroconductive textiles by coating conductive polymer PEDOT:PSS (Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) on biocompatible PLA (Poly Lactic Acid) nanofiber web for application to smart healthcare. Electroconductive textiles were obtained by a drop-coating process using different amounts of PEDOT:PSS solutions., DMSO (dimethyl sulfoxide) was then used as an additive in the post-treatment process to improve conductivity. The surface morphology of the specimens was observed by FE-SEM. The chemical structures of the specimens were characterized using FTIR. The electrical properties (linear and sheet resistance) of the specimens were measured. The effect of the bending angles on the electrical properties was also investigated to confirm their applicability as wearable smart textiles. FE-SEM and FTIR analysis confirmed that the deposition of PEDOT:PSS on the PLA nanofiber web surface was successful. The conductivity of the PEDOT:PSS/PLA nanofiber web was enhanced up to 1.5 ml with an increasing amount of PEDOT:PSS solutions, but there was no significant difference at 2.0 ml. The optimum condition of PEDOT:PSS deposition was established to 1.5 ml. Even when the specimen coated with 1.5 ml was bent every 30°, the change in the electrical resistance values was still low within 3.7 Ω. It confirmed that stable electrical performance was maintained and proved the applicability as a flexible textile sensor.

• Journal of Life Science
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• v.33 no.11
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• pp.936-943
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• 2023

This study was conducted to investigate the potential of Stewartia koreana as anti-microbial materials. The branches, stems and leaves of S. koreana were extracted into 70% ethanol and their antibacterial activity against P. aeruginosa was confirmed. The leaf, branch and stems extracts (1 mg/disc) showed the antibacterial activity against P. aeruginosa and leaf extracts showed higher antibacterial activities than those from branch extracts. The MIC against P. aeruginosa was 0.8 mg/ml and showed bacteriostatic action. The inhibitory effects of extract on biofilm formation and gene expression related to biofilm formation of P. aeruginosa was determined by biofilm biomass staining, SEM and qRT-PCR analysis. The biofilm biomass and cell growth of P. aeruginosa in the cultures treated with 0.2~2.0 mg/ml of S. koreana leaf extracts were significantly decreased in a concentration-dependent manner. We observed that the extract had an inhibitory effect on the formation of P. aeruginosa biofilms at concentrations of 0.8 mg/ml by SEM. qRT-PCR analysis showed that the lasI and rh1I gene expression associated to quorum sensing (QS) in the cultures treated with 0.2~2.0 mg/ml of S. koreana leaf extracts were suppressed in a concentration-dependent manner. Based on the above results, it can be concluded that S. koreana leaf extracts can be used as anti-microbial material derived from natural materials, as demonstrated by the antibacterial action and inhibition of biofilm formation of P. aeruginosa by QS inhibition.