• 대한치과교정학회지
• /
• 제48권4호
• /
• pp.245-252
• /
• 2018

Objective: We aimed to perform in-vitro evaluation to compare 1) shear bond strength (SBS), adhesive remnant index (ARI), and color change between self-etched and acid-etched primers; 2) the SBS, ARI and color change between direct and indirect bonding; and 3) the enamel roughness (ER) between 12-blade bur and aluminum oxide polisher debonding methods. Methods: Seventy bovine incisors were distributed in seven groups: control (no bonding), direct (DTBX), and 5 indirect bonding (ITBX, IZ350, ISONDHI, ISEP, and ITBXp). Transbond XT Primer was used in the DTBX, ITBX, and ITBXp groups, flow resin Z350 in the IZ350 group, Sondhi in the ISONDHI group, and SEP primer in the ISEP group. SBS, ARI, and ER were evaluated. The adhesive remnant was removed using a low-speed tungsten bur in all groups except the ITBXp, in which an aluminum oxide polisher was used. After coffee staining, color evaluations were performed using a spectrophotometer immediately after staining and prior to bonding. Results: ISONDHI and ISEP showed significantly lower SBS (p < 0.01). DTBX had a greater number of teeth with all the adhesive on the enamel (70%), compared with the indirect bonding groups (0-30%). The ER in the ITBX and ITBXp groups was found to be greater because of both clean-up techniques used. Conclusions: Direct and indirect bonding have similar results and all the primers used show satisfactory adhesion strength. Use of burs and polishers increases the ER, but polishers ensure greater integrity of the initial roughness. Resin tags do not change the color of the teeth.

• 동의생리병리학회지
• /
• 제21권5호
• /
• pp.1148-1153
• /
• 2007

Streptococcus mutans is considered one of the primary etiologic agents of dental caries. we studied the effect of the ethanol extracts of Tribuli fructus (T. fructus) on the growth, biofilm formation, acid production, adhesion and insoluble glucan synthesis of S. mutans. The ethanol extracts of T. fructus showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 0.025, 0.05, 0.1, 0.2, 0.3, 0.5 mg/ml compared to the control group. In the biofilm assay, the ethanol extracts of T. fructus inhibited formation of biofilm synthesized by S. mutans at the concentration of 0.05 mg/ml. The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration 0.05 mg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan form sucrose, ethanol extract of T. fructus showed more than 10% inhibition over the concentration of 0.025 mg/ml. Hence, we conclude that T. fructus might be a candidate of anticaries agent. Further studies are necessary to clarify the active constituents of T. fructus responsible for such biomolecular activities.

• 한국전기전자재료학회논문지
• /
• 제26권6호
• /
• pp.425-428
• /
• 2013

In this paper, we present a novel hydrophilic coating material (Wellture Finetech, Korea) which can be utilized as a coating layer for anti-contamination for electrical and electronic system. The coating material was deposited on 4 inch silicon wafer with several different film thickness. The film thickness was controlled by spin coating speed. After curing of the film, we have scratched by permanent marker to check self-cleaning property of the film. Also we have executed several mechanical tests of the films. As the spin coating speed is increased, the film thickness was thinned from 230 nm to 125 nm. Contact angle of the film was lowered from $30^{\circ}$ to $12^{\circ}$ as the spin coating speed is increased from 700 to 2,500 rpm. On permanent marker scratched film surface coated at 1,000 rpm, we have poured regular city water to investigate self cleaning property of the film. The scratches were gradually separated from the film surface due to super-hydrophilicity of the film. Hardness of spin coated film was 9H measured by ASTM D3363 method. and adhesion of all film was 5B tested by ASTM D3359 method. Also, to get exact hardness value of the film, we have utilized a nano-indenter. As spin speed is increased, the hardness of film was increased from 3 GPa to 5 GPa.

• 펄프종이기술
• /
• 제41권4호
• /
• pp.73-81
• /
• 2009

The document archives like official documents, books, maps and historic paper artifacts are primarily based on the organic cellulosic materials. As the passage of time, these organic cellulosic materials are slowly deteriorated by various aging factors, like light, polluted air and biological fungi. Many researchers have been carried out the examination method of deteriorating origins, the mechanism of aging hysteresis, and the preserving method of archival materials. One of the most simple and easiest ways for conservation of organic archival documents is the proper storage under environmental control. Corrugated board for archival quality container has been developed and already used in advanced country, like Japan, USA, German, UK and Europe. In case of Korea, corrugated board for archival quality container has been used a decade ago, but totally imported. This study was tried to develop the corrugated board for archival quality container. Liner and corrugated medium were specially produced and finally manufactured to E flute corrugated board. The physical and strength properties of permanent base paper and corrugated board were evaluated, and compared with imported corrugated board. 4 kinds of corrugating adhesives were considered various in order to investigate optimum adhesive for flute development between liner and corrugating medium, and evaluate adhesion strength under conditions of storage and curing temperatures.

• 한국미생물·생명공학회지
• /
• 제47권4호
• /
• pp.487-497
• /
• 2019

Fetal Bovine Serum (FBS) is an essential substance added to animal cell culture medium. However, its composition is unclear causing problems such as development of an immune response when cultured cells are transplanted into the human body. In this study, silk sericin, silk fibroin, and hemolymph obtained from silkworms were added to the cell culture medium in order to determine if it can replace FBS. After establishment of the cell culture, cell proliferation and expression levels of cell growth-related genes were compared with those of control cells (cells cultured in the medium with 10% FBS). Results showed that the test group treated with silk fibroin extracted from a Korean silkworm variety, Kumokjam could replace 10% FBS. In addition, expression levels of cell growth related genes such as Fibronectin and TGF-β1 increased significantly in cells cultured using silk fibroin, depending on the concentration used in cell adhesion and cell proliferation [24]. To date, no studies have been conducted to find a replacement for FBS. Thus, this study was carried out to develop a substitute for FBS by using silkworm-derived alternatives such as silkworm hemolymph, silk sericin, and silk fibroin, which are cheap and have various physiological effects, cell promoting effects, and can be mass produced.

• Journal of Microbiology and Biotechnology
• /
• 제29권12호
• /
• pp.1894-1903
• /
• 2019

The purpose of this study was to determine the probiotic properties of Lactobacillus brevis KCCM 12203P isolated from the Korean traditional food kimchi and to evaluate the antioxidative activity and immune-stimulating potential of its heat-killed cells to improve their bio-functional activities. Lactobacillus rhamnosus GG, which is a representative commercial probiotic, was used as a comparative sample. Regarding probiotic properties, L. brevis KCCM 12203P was resistant to 0.3% pepsin with a pH of 2.5 for 3 h and 0.3% oxgall solution for 24 h, having approximately a 99% survival rate. It also showed strong adhesion activity (6.84%) onto HT-29 cells and did not produce β-glucuronidase but produced high quantities of leucine arylamidase, valine arylamidase, β-galactosidase, and N-acetyl-β-glucosaminidase. For antioxidant activity, it appeared that viable cells had higher radical scavenging activity in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, while in the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, heat-killed cells had higher antioxidant activity. Additionally, L. brevis KCCM 12203P showed higher lipid oxidation inhibition ability than L. rhamnosus GG; however, there was no significant difference (p < 0.05) between heat-killed cells and control cells. Furthermore, heat-killed L. brevis KCCM 12203P activated RAW 264.7 macrophage cells without cytotoxicity at a concentration lower than 10⁸ CFU/ml and promoted higher gene expression levels of inducible nitric oxide synthase, interleukin-1β, and interleukin-6 than L. rhamnosus GG. These results suggest that novel L. brevis KCCM 12203P could be used as a probiotic or applied to functional food processing and pharmaceutical fields for immunocompromised people.

• 한국패류학회지
• /
• 제30권3호
• /
• pp.169-175
• /
• 2014

PAHs (Polycyclic Aromatic Hydrocarbons: PAHs) is the hydrophobic inorganic material composed of carbon and hydrogen that is easily adsorbed biological organisms in the ocean. Bivalves is the indicator of environment monitoring because of reflect growth, physiological response of bivalve followed their habitat environment. The aim of research is understand the change of oysters (Crassostrea gigas) physiological response under exposed PAHs concentration for control, 1, 10 and $100{\mu}g/L$. We investigated induced immune change response for oyster hemocyte and effect of tissue RNA/DNA ratio for mantle, gill and adductor muscle individually. As a result of experiment change of immune response the oyster hemocyte when exposed PAHs showed that viability and adhesion is no significant difference (ANOVA test, p < 0.05). However phagocytosis decreased under the over $10{\mu}g/L$ of PAHs concentration and ROS increased with the increase of PAHs concentration. The change of RNA/DNA ratio is R/D ratio decreased with the increase of PAH concentration in adductor muscle. However gill and mantle showed no change of R/D ratio with PAHs concentration. The oysters when exposed inorganic pollutant that decreased of physiological condition and damaged protein synthesis of adductor muscle.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권22호
• /
• pp.9791-9795
• /
• 2014

To study the gene expression change and possible signal pathway during androgen-dependent prostate cancer (ADPC) becoming androgen-independent prostate cancer (AIPC), an LNCaP cell model of AIPC was established using flutamide in combination with androgen-free environment inducement, and differential expression genes were screened by microarray. Then the biological process, molecular function and KEGG pathway of differential expression genes are analyzed by Molecule Annotation System (MAS). By comparison of 12,207 expression genes, 347 expression genes were acquired, of which 156 were up-ragulated and 191 down-regulated. After analyzing the biological process and molecule function of differential expression genes, these genes are found to play crucial roles in cell proliferation, differntiation, cell cycle control, protein metabolism and modification and other biological process, serve as signal molecules, enzymes, peptide hormones, cytokines, cytoskeletal proteins and adhesion molecules. The analysis of KEGG show that the relevant genes of AIPC transformation participate in glutathione metabolism, cell cycle, P53 signal pathway, cytochrome P450 metabolism, Hedgehog signal pathway, MAPK signal pathway, adipocytokines signal pathway, PPAR signal pathway, TGF-${\beta}$ signal pathway and JAK-STAT signal pathway. In conclusion, during the process of ADPC becoming AIPC, it is not only one specific gene or pathway, but multiple genes and pathways that change. The findings above lay the foundation for study of AIPC mechanism and development of AIPC targeting drugs.

• Restorative Dentistry and Endodontics
• /
• 제33권6호
• /
• pp.553-559
• /
• 2008

이 연구의 목적은 레진 코팅된 표면과 레진인레이 사이의 자가-접착 레진시멘트를 이용한 결합 시 임시가봉제에 따른 미세인장결합강도를 평가하는 것이었다. Caviton(GC, Tokyo, Japan), Provifil(Promedica, Neumunster, Germany), Provifil(Promedica, Neumunster Germany) & petrolatum, and Eugenol-based cement, Tembond(Kerr, Orange. CA, USA) 이 임시가봉재로 사용되었다. Tescera(Bisco, Schamburg IL, USA) 로 제작하였고 자가-접착 레진시멘트인 Rely X unicem (3M, St. Paul. Minn, USA) 를 이용하여 접착하였다. 이후 미세인 장결합강도를 측정하였고 one-way anova 와 Duncan test 를 이용하여 분석하였다.(p<0.05) Caviton 군이 다른 그룹과 비교하여 유의성 있는 차이를 보여주었다(p<0.05). Provifil, Provifil & petrolatum, Tembond 군 등은 상대적으로 낮은 값을 보여주었다.

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.268-268
• /
• 2006

Due to their multipotency, stem cells can differentiate into a variety of specialized cell types, such as chondrocytes, osteoblasts, myoblasts, and nerve cells. As an alternative to mature tissue cells, stem cells are of importance in tissue engineering and regenerative medicine. Since interactions between scaffold and cells play an important role in the tissue development in vitro, synthetic oligopeptides have been immobilized onto polymeric scaffolds to improve specific cell attachment and even to stimulate cell differentiation. In this study, chondrogenic differentiation of stem cells was evaluated using surface-modified PLLA scaffolds, i.e., either hydrophilic acrylic acid (AA)-grafted PLLA or RGD-immobilized one. Porous PLLA scaffolds were prepared using a gas foaming method, followed by plasma treatment and subsequent grafting of AA to introduce a hydrophilicity (PLLA-PAA). This was further processed to fix RGD peptide to make an RGD-immobilized scaffold (PLLA-PAA-RGD). Stem cells were seeded at $1{\times}10^{6}$ cells per scaffold and the cell-PLLA constructs were cultured for up to 4 weeks in the chondrogenic medium. Using these surface-modified scaffolds, adhesion, proliferation, and chondrogenic differentiation of stem cells were evaluated. The surface of PLLA scaffolds turned hydrophilic (water contact angle, 45 degrees) with both plasma treatment and AA grafting. The hydrophilicity of RGD-immobilized surface was not significantly altered. Cell proliferation rate on the either PLLA-PAA or PLLA-PAA-RGD surface was obviously improved, especially with the RGD-immobilized one as compared to the control PLLA one. Chondrogenic differentiation was clearly identified with Safranin O staining of GAG in the AA- or RGD-grafted PLLA substrates. This study demonstrated that modified polymer surfaces may provide better environment for chondrogenesis of stem cells.