• 한국세라믹학회:학술대회논문집
• /
• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
• /
• pp.133.1-133
• /
• 2003

• 한국재료학회지
• /
• 제20권7호
• /
• pp.392-400
• /
• 2010

The electrospinning process was established as a promising method to fabricate nano and micro-textured scaffolds for tissue engineering applications. A BCP-loaded PCL micro-textured scaffold thus can be a viable option. The biocompatibility as well as the mechanical properties of such scaffold materials should be optimized for this purpose. In this study, a composite scaffold of poly ($\varepsilon$-caprolactone) (PCL)-biphase calcium phosphate (BCP) was successfully fabricated by electrospinning. EDS and XRD data show successful loading of BCP nano particles in the PCL fibers. Morphological characterization of fibers shows that with a higher loaded BCP content the fiber surface was rougher and the diameter was approximately 1 to 7 ${\mu}m$. Tensile modulus and ultimate tensile stress reached their highest values in the PCL- 10 wt% BCP composite. When content of nano ceramic particles was low, they were dispersed in the fibers as reinforcements for the polymer matrix. However, at a high content of ceramic particles, the particles tend to agglomerate and lead to decreasing tensile modulus and ultimate stress of the PCL-BCP composite mats. Therefore, the use of nano BCP content for distribution in fiber polymer using BCP for reinforcement is limited. Tensile strain decreased with increasing content of BCP loading. From in vitro study using MG-63 osteoblast cells and L-929 fibroblast like cells, it was confirmed that electrospun PCL-BCP composite mats were biocompatible and that spreading behavior was good. As BCP content increased, the area of cell spreading on the surface of the mats also increased. Cells showed the best adherence on the surface of composite mats at 50 wt% BCP for both L-929 fibroblast-like cells and MG-63 osteoblast cell. PCL- BCP composites are a promising material for application in bone scaffolds.

• 전기학회논문지P
• /
• 제63권3호
• /
• pp.212-217
• /
• 2014

The electric power output characteristics of magnesium fuel cell were investigated with regard to internal resistance. A equivalent circuit with the series-connected three internal resistance was introduced to analyze of the response to change of power. The power output analysis was employed in order to investigate the effect of internal resistances for the electrolyte concentration, air electrode area, Mg electrode area and distance between the electrodes. It was confirmed that internal resistance is generated by the electrolyte, air electrode and metal electrode, then those Internal resistances had a significant effect on the power output decrease. The power output was a maximum when the load resistance maches the internal resistance of the magnesium fuel cell. The fuel efficiency was only 50% at maximum power output. Higher fuel efficiency was achieved when the load resistance is greater than the internal resistance.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제31권5호
• /
• pp.363-369
• /
• 2005

Purpose: To determine the role of Insulin-like Growth Factor-I (IGF-I) in the regulation of Vascular Endothelial Growth Factor (VEGF) expression in MG-63 cells and then to find the mechanism b which this regulation occurs. Materials and methods: MG-63 cells were grown to confluence in 60-mm dishes. To determine the effects of IGF-I on expression of VEGF mRNA according to time and concentration, the cells were treated with 10 nM IGF-I, following isolation of total RNA and Northern blot analysis after 1, 2, 4, 8, 12, 24 hours and after 2 hours of treatment with 0.5, 2, 10, 25, 50 nM IGF-I respectively, isolation of total RNA and Northern blot analysis were followed. To determine the mechanism of action of IGF-I, inhibitors such as hydroxyurea $(76.1\;{\mu}g/ml)$, actinomycin D $(2.5\;{\mu}g/ml)$, cycloheximide $(10\;{\mu}g/ml)$ were added 1 hour after treatment of 10 nM IGF-I. Results: 1. the expression of VEGF mRNA was increased with treatment of IGF-I. 2. The expression of VEGF mRNA was increased according to time-and concentration dependent manner of IGF-I. 3. The effect of IGF-I was decreased by hydroxyuera, actinomycin D, but not by cycloheximide. Conclusion: IGF-I regulate the expression of VEGF mRNA in the level of DNA synthesis and transcription. These results could suggest that IGF-I plays an important role in angiogenesis in the process of new bone formation and remodeling.

• International Journal of Oral Biology
• /
• 제33권3호
• /
• pp.105-111
• /
• 2008

Thrombospondins (TSP-1, TSP-2) are secretory extracellular glycoproteins that are involved in a variety of physiological processes such as tumor cell adhesion, invasion, and metastasis. The present study was undertaken to elucidate the involvement of thrombospondins in the adhesion of osteoblast-like cells using the TSP-1 or TSP-2 antisense MG63 and MC3T3-E1 cell lines. For downregulation of TSPs expression, we prepared antisense constructs for TSP-1 and TSP-2 using the pREP4 an episomal mammalian expression vector, which be able to produce the specific antisense oligonucleotides around chromosome. MG63 and MC3T3-E1 osteoblast-like cells were transfected with the antisense constructs and nonliposomal Fugene 6, and then selected under hygromycin B (50 ${\mu}g/ml$) treatment for 2 weeks. Western blot analysis revealed that expression of the TSP proteins was downregulated in the antisense cell lines. The cell adhesion assay showed that adhesive properties of TSP-1 and TSP-2 antisense MG63 cells on the polystyrene culture plate were reduced to 17% and 21% of the control cells, respectively, and those of the TSP-1 and TSP-2 antisense MC3T3-E1 cells also decreased to 19% and 27% of control, respectively. Adhesion of TSP-1 and TSP-2 antisense MC3T3-E1 cells on Type I collagen-coated culture plate decreased to 27% and 76%, respectively. These results indicate that TSP-1 and TSP-2 proteins may have an important role in adhesion of osteoblast-like cells to extracellular matrix.

• 한국식품과학회지
• /
• 제15권2호
• /
• pp.170-176
• /
• 1983

미생물을 이용한 식량자원개발의 일환으로 분리배양한 전분이용성 효모, Sporobolomyces holsaticus FRI Y-5의 균체성분에 대하여 검토하였다. 효모균체의 일반조 성분으로서 총 탄수화물이 33.08%, 조단백질이 45.63%, 조지방이 20.01%, 회분이 3.04%였으며, 그 밖에 색소수출물이 4.46%였다. 완전세포(Whole cell)의 가용성단백질함량은 cold and hot NaOH extraction 시 40.89%였으며, 이때 조단백질과 가용성단백질 함량으로부터 핵산함량이 7.6%로 추정되었다. 균체단백질의 아미노산 분석결과, 표준단백질에 비하여 필수아미노산 중 threonine, valine, isoleucine이 약간 적었으며 그때 제한아미노산인 valine의 단백가는 89.4였다. 균체지방의 지방산 조성은 $C_{16:0}$이 6.5%였고, $C_{18:0}$이 2.4%, $C_{18:1}$이 81.9%, $C_{18:2}$이 3.2%, $C_{18:3}$이 6.0%였으며, 이 때 $C_{18:1}$이 특이하게 많았다. 또한 이 효모균체는 미량원소로서 Fe나 Ca에 비하여 Mg과 K을 많이 함유하고 있었으며, 각각 365.33mg/100g, 282.75mg/100g이었고, 비타민 중 $Vit.\;B_2$는 3.7mg/100g이나 niacin은 검출되지 않았다. 색소수출물의 흡광도 실험결과, carotenoid계 색소가 확인되었으며 자외선부분에서 태양광에 파괴되지 않는 물질을 발견하였다.

• 한국재료학회지
• /
• 제22권6호
• /
• pp.285-291
• /
• 2012

Hydroxyapatite (HA) is well known as a biocompatible and bioactive material. HA has been practically applied as bone graft materials in a range of medical and dental fields. In this study, two types of dense hydroxyapatite ceramics were prepared from natural bones and synthetic materials. The biocompatibility of HA ceramics for supporting osteoblast cell growth and cytotoxicity using an in vitro MG-63 cell line model were respectively evaluated. Artificial hydroxyapatite shows relative density of 93% with 1-2 ${\mu}m$ after sintering, but a hydroxyapatite compact derived from bovine bone has low sintered density of 85% with a small content of MgO. Irrespective of the starting raw materials, both types of sintered hydroxyapatite displayed similar biocompatibility in the tests. FE-SEM observations showed that most MG-63 cells had a stellar shape and formed an intercellular matrix containing fibers on sintered HA. The cells were well attached and grown over the HA surface, indicating that there was no toxicity.

• Journal of Nutrition and Health
• /
• 제48권2호
• /
• pp.157-166
• /
• 2015

골기능 개선용 흑염소 액상제품을 개발하기 기초연구로서 흑염소 및 약용식물 복합추출물이 MG-63 조골세포 및 마우스 골수세포 유래 파골세포의 분화에 미치는 영향을 분석하였다. 흑염소 원료육의 일반성분, 휘발성 염기질소, 무기질함량, 유리아미노산 조성 및 지방산 조성 등의 영양성분을 분석하여 기초자료를 마련하였다. 흑염소에 첨가할 약용식물의 종류와 배합을 달리한 두 그룹의 한약재 첨가군에 대해 증탕추출액과 증류액을 제조하여 총 6개 시료군 (흑염소육 (BG-E, BG-D), 6종 한약재 첨가군 (BG-E6, BG-D6) 및 8종 한약재 첨가군 (BG-E8, BG-D8)을 대상으로 골강화 활성을 분석하였다. 식품공전상 식품의 원료로 사용이 가능한 원료 중 황기, 홍화씨, 당귀, 황정, 속단, 우슬 각각 2/2/2/2/1/1의 배합비를 지닌 한약재 6종 첨가군 및 동일배합에 녹용과 녹각을 각각 0.3/1.2 로 추가배합한 한약재 8종 첨가군을 사용하였다. 조골세포 MG-63의 증식 촉진 활성에 대해 시료별 및 농도별로 유의적인 차이가 나타났으며 한약재 무첨가 흑염소군보다 6종 및 8종 등 한약재 첨가량이 많을수록 활성이 증가하였다. 증탕추출액과 달리 증류액은 모두 유의한 효과가 없었다. 조골세포의 골석회화 촉진활성시험 결과 대조군에 비해 모든 시료 처리군에서 칼슘함량이 유의적으로 증가하여 MG-63 세포의 석회화 결절 형성을 농도 의존적으로 유의하게 증가시켰다. BG-E6는 대조군에 비해 석회화 형성을 170.3% 증가시켰고, 증류액인 BG-D와 BG-D6는 각각 168.5% 및 159.8%의 증가를 나타내었다. 시료별 차이에 있어 한약재 첨가군이 무첨가군보다 높았고, 증탕추출액이 증류액보다 높은 활성을 보였다. 세포의 칼슘 흡수량을 측정한 결과 모든 증탕추출액에서 활성이 증가하였고 특히 BG-E6와 BG-E8은 각각 615.5%와 628.1%로 유의적으로 가장 높은 증가율을 보였다. 증류액은 BG-D6의 1/10 농도군외에 효과가 없었다. 마우스 골수세포 유래 파골세포의 증식억제 실험결과 TNF-${\alpha}$ 만을 처리한 대조군에 비해 모든 시료군이 TRAP활성을 억제하는 경향을 나타내었다. 특히 BG-D 및 BG-E6, BG-E8은 유의하게 파골세포로의 분화를 억제하였다. 종합적으로 흑염소육을 비롯하여 황기, 홍화씨, 당귀, 황정, 속단, 우슬, 녹용 및 녹각 등 한약재의 복합추출물은 골 기능 강화에 매우 효과적인 기능성 원료가 될 수 있을 것으로 사료된다.

• Journal of Animal Science and Technology
• /
• 제63권5호
• /
• pp.1194-1203
• /
• 2021

Preparation of recipient stallions is critical step to produce donor spermatogonial stem cell (SSC) derived sperm using transplantation technique. This study was conducted to evaluate the effects of intravenous busulfan infusion on germ cell depletion, semen production, and libido in stallions. Six Thoroughbred stallions were separated into two treatment groups: 1) a multiple low-dose (2.5 mg/kg bw for the first 4 weeks and 5 mg/kg bw for the 5th week); and 2) control group treated with PBS. Testicular samples were obtained at 11 weeks and classified into three different patterns of spermatogenesis, such as normal, Sertoli cell only, and destroyed. Semen collection and libido experiments were performed 1 week before treatment, and 4 and 8 weeks after treatment. For the sperm analysis, total spermatozoa and motility were measured using a light microscope with a motility analyzing system. In the multiple low-dose group, the numbers of tubules categorized as Sertoli cell only were significantly higher than those in the control as well as the total population and total/progressive motility of sperm were significantly decreased 8 weeks after the start of the treatment. The sperm production and motility in the multiple low-dose group appears to be reduced, while libido was maintained. In conclusion, multiple administration of 2.5 mg/kg bw busulfan depletes endogenous germ cells in the stallion recipients for SSC transplantation.

• KSBB Journal
• /
• 제24권2호
• /
• pp.177-181
• /
• 2009

This study was initiated to investigate the impacts of media types and other components on the callogenensis and cell mass production of Panax vietnamensis in the first step of the cell biomass procedure. Four media were checked: Murashige-Skoog (MS), White, Gamborg and Nitch-AII. All the four media were shown potential media for Panax vietnamensis callogenensis and cell mass production, in which the MS medium showed the best results: the successful callogenensis ratio and cell mass formation were 30% and 62,93 ${\pm}$ 3,63 mg (DW) respectively, the Nitch medium showed the lowest results: the successful callogenensis ratio and cell mass formation were 15% and 27,10 ${\pm}$ 2,24 mg (DW) respectively. The results showed that the MS medium is the most suitable medium for Panax vietnamensis callogenensis and cell mass production.