https://oak.chosun.ac.kr/handle/2020.oak/18942 2026-04-09T17:44:05Z 2026-04-09T17:44:05Z Kyong Sup Yim Su Gwan Kim Byung Sun Park Dae San Go Chun Sung Kim Do Kyung Kim https://oak.chosun.ac.kr/handle/2020.oak/18963 2024-04-29T07:20:52Z 2015-12-31T15:00:00Z

Title: Resveratrol induces the apoptosis associated with activation of caspases in HTB-41 human salivary gland epidermoid carcinoma cells Author(s): Kyong Sup Yim; Su Gwan Kim; Byung Sun Park; Dae San Go; Chun Sung Kim; Do Kyung Kim Abstract: Trans-3,4`,5,-trihydroxystilbene (resveratrol), a phytoalexin that is present in grape skin and red wine, suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms. However, resveratrol`s effects on salivary gland tumors including squamous carcinomas are not clearly established. The main goal of this study was to investigate the effect of resveratrol on cell growth and induction of apoptosis in salivary gland epidermoid carcinoma cells. Treatment with resveratrol induced inhibition of cell growth and was dependent on resveratrol treatment time and concentration in HTB-41 cells. Treatment with resveratrol induced nuclear condensation and fragmentation in HTB-41 cells. Activation of caspases-3 and -7 was detected in living HTB-41 cells by fluorescence microscopy. Resveratrol promoted proteolytic cleavage of procaspases-3, -7, -8 and -9 with increases in the amount of cleaved caspases- 3, -7, -8 and -9. Cleaved PARP increased consider in the presence of resveratrol in HTB-41 cells. These results suggest that resveratrol can induce the suppression of cell growth and cell apoptosis in HTB-41 human submaxillary salivary gland epidermoid carcinoma cells, and that it may have potential properties for anti-cancer drug development.

2015-12-31T15:00:00Z Young Tae Kim Jun Young Cha Xing Hui Piao Young Joon Kim https://oak.chosun.ac.kr/handle/2020.oak/18964 2024-04-29T07:20:52Z 2015-12-31T15:00:00Z

Title: Osteoblast responses of thermally oxidized magnesium-calciummanganese alloy Author(s): Young Tae Kim; Jun Young Cha; Xing Hui Piao; Young Joon Kim Abstract: Magnesium alloys are considered as potential biomedical materials due to their mechanical properties, which approximate cortical bone, as well as their biocompatibility. Thermal oxidation is one surface modification method used to increase the corrosion resistance of biomaterial surfaces. Thus, the aim of this study is to assess physical and biological differences of Mg-Ca-Mn alloy depending on oxidation heat treatment methods. The sample were divided into 3 groups: Group II: pure magnesium as a control group; Group II: untreated Mg-Ca-Mn alloy; Group III: Mg-Ca-Mn alloy treated at 500℃ for 2 hours. Scanning electron microscope assessment, immersion test, roughness test, and MTT assay were used to evaluate surface characteristics and physical and biologic properties of each sample. Oxide-treated Mg-Ca-Mn alloy treated thermally (Group III) showed an oxidized layer and precipitate with granular structure on the surface. During the immersion test, no significant difference was shown in pH values between the groups. The roughness measurements in Group I and Group III were significantly higher than the value in Group II, while there was no meaningful difference between Group I and Group III. The cell viability of Group III was higher than that of Group II, and statistically significant differences were observed on the third and fifth days. Also, significant differences were confirmed in Group III on the third and fifth days. Consequently, oxidation heat treatment, among various methods of surface treatment, can be considered as one method to improve properties in biocompatible materials by creating an oxidation layer on Mg-Ca-Mn alloys.

2015-12-31T15:00:00Z Seul Kee Kim Jae Kwan Lee Se Hwan Park Beom Seok Chang Si Young Lee Heung Sik Um https://oak.chosun.ac.kr/handle/2020.oak/18962 2024-04-29T07:20:52Z 2015-12-31T15:00:00Z

Title: Altered bacterial adhesion with changes in roughness of titanium surfaces after implant cleaning Author(s): Seul Kee Kim; Jae Kwan Lee; Se Hwan Park; Beom Seok Chang; Si Young Lee; Heung Sik Um Abstract: Although various instruments have been devised to treat peri-implantitis, none has become the technique of choice. Recently, a new implant cleaning bur was introduced. We compared the surface roughness and bacterial adhesion on implants after surface cleaning with various instruments. Two types of titanium disks - resorbable blasting media (RBM) and sandblasting with large grit and acid etching (SLA) - were used. Following treatments were administered: (1) no treatment; (2) tetracycline; (3) implant cleaning bur; (4) air polisher with glycine powder; and (5) copper alloy ultrasonic scaler tip. We measured the titanium surface roughness after cleaning. We also observed surface changes with scanning electron microscopy, and evaluated the bacterial adhesion related to changes in surface roughness. The surface roughness of RBM disks decreased significantly only in the third group. SLA disks in the third and fifth groups showed significantly decreased roughness. No significant difference in bacterial adhesion was found on treated RBM surfaces. The third and fifth groups also had significantly decreased bacterial adhesion on the SLA surfaces. The implant cleaning bur reduced the roughness of RBM and SLA titanium implants, and decreased the adhesion of bacteria on SLA surfaces, which may help prevent the recurrence of peri-implantitis.

2015-12-31T15:00:00Z In Seok Lee Xing Hui Piao Young Joon Kim Ki Deog Park https://oak.chosun.ac.kr/handle/2020.oak/18966 2024-04-29T07:20:52Z 2015-12-31T15:00:00Z

Title: Cell proliferating responses to magnesium coated β-TCP surface Author(s): In Seok Lee; Xing Hui Piao; Young Joon Kim; Ki Deog Park Abstract: Bioactive calcium phosphate ceramics, such as hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), have been considered for use as synthetic bone graft substitutes in regenerative surgeries. However, the rate of bioresorption of β-TCP is unpredictable. In order to resolve the drawbacks of β-TCP, coatings of bioactive materials on the apatite graft base materials were introduced. Magnesium (Mg) plays a crucial role in cell proliferation and function. Cells are unable to proliferate in the absence of extracellular Mg because of the resultant reduction in DNA, RNA and protein synthesis. This study was performed to evaluate early osteoblastic cell responses to Mg coated β-TCP surfaces. The bioactive surfaces on β-TCP base were developed by radio frequency (RF) magnetron coating method. Thin Mg coating on β-TCP substrates was performed. Surface characteristics were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The bioactivity of coated surfaces was also evaluated by SEM and cell proliferation. The disks were divided into 2 groups: control group (TCP) and test group (TCP-Mg). SEM and EDX analysis showed that Mg deposition on the β-TCP substrates were performed successfully. Under SEM, no significant difference in cell morphology was observed between the TCP and TCP-Mg groups. In the MTT assay, the TCP-Mg group had significantly better cellular responses with regard to proliferation at 5 days (p<0.05). Within certain limitations, the results of this study suggests that Mg coatings on β-TCP offers great potential as a graft material for hard tissue regeneration.

2015-12-31T15:00:00Z