• BMB Reports
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• v.49 no.3
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• pp.179-184
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• 2016

Bone morphogenetic protein 9 (BMP9) is a potent inducer of osteogenic differentiation of mesenchymal stem cells. The Wnt antagonist Dickkopf-1 (Dkk1) is involved in skeletal development and bone remodeling. Here, we investigated the role of Dkk1 in BMP9-induced osteogenic differentiation of MSCs. We found that overexpression of BMP9 induced Dkk1 expression in a dose-dependent manner, which was reduced by the P38 inhibitor SB203580 but not the ERK inhibitor PD98059. Moreover, Dkk1 dramatically decreased not only BMP9-induced alkaline phosphatase (ALP) activity but also the expression of osteocalcin (OCN) and osteopontin (OPN) and matrix mineralization of C3H10T1/2 cells. Furthermore, exogenous Dkk1 expression inhibited Wnt/β-catenin signaling induced by BMP9. Our findings indicate that Dkk1 negatively regulates BMP9-induced osteogenic differentiation through inhibition of the Wnt/β-catenin pathway and it could be used to optimize the therapeutic use of BMP9 and for bone tissue engineering.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.529-532
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• 2005

Expanding cells ex-vivo is very important in tissue-engineering. Culture medium is usually supplemented with fetal bovine serum(FBS) in most of the experiments. However, cells grown in bovine serum media may posses the possibilities of disseminating bovine diseases and/or stimulating the patient's immune reactions. To overcome these problems, autologous or homologous serum should be used instead of the FBS. The purpose of this study is to compare cell proliferation and collagen synthesis depending on the kind of sera mixed on media and to provide a guideline on applying established experimental data to clinical cases. Human dermal fibroblasts were obtained from four patients. Five thousand cells per well in 96-well plates were incubated DMEM/F-12 Nutrient with varying serum mixture; 10% autologous serum, 10% homologous serum, and 10% FBS. Five days after incubation fibroblast proliferation and collagen production were determined by MTT assay and CICP enzyme immunoassay. The mean cell number were; $3.95{\times}10^4/well$, $2.97{\times}10^4/well$ and $2.30{\times}10^4/well$, respectively. The average amounts of collagen synthesized were; 238.13 ng/ml, 204.88 ng/ml, and 163.88 ng/ml in each. These results show that the use of human serum mixture may contribute to, not only preventing disseminated infection of bovine diseases. but also increase cell proliferation and collagen synthesis without simulating the patient's immune reactions.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.507-513
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• 2008

Purpose: Interest in the augmentation of hair growth for functional and aesthetic purpose has increased dramatically in recent years. Many hair growth products have been released, but most of these have not been proven scientifically. This study aims to measure the hair growth effect of azelaic acid and vitamin $B_6$, which have been known as hair growth materials, in animal models. Methods: Six weeks old C57BL/6 mice were used in this study and hair of mice were removed by topical treatment. The mice were divided into five experimental groups according to the testing material such as saline (negative control), propylene glycol(vehicle control), azelaic acid, vitamin B6 and azelaic acid plus vitamin B6 in combination. Hair growth was documented photographically and histologically, and then analysed by the high quality hair analysis program system. The quantity of endocrine factors, IGF-I and TGF-${\beta}1$ in the skin of mice was measured by PCR analysis. Results: The topical treatment of azelaic acid and vitamin B6 in combination for 2 weeks to dorsal skin accelerated hair regrowth more than other groups. The azelaic acid and vitamin $B_6$-combined treatment also promoted hair follicle elongation and thickness compared to the others. Histologic studies showed increased number of basal cells in azelaic acid and vitamin $B_6$-combined treatment. Furthermore, the azelaic acid and vitamin $B_6$-combined group significantly increased the expression of IGF-I but decreased the expression of TGF-${\beta}1$ in the skin of mice compared to other groups. Conclusion: These results suggest that azelaic acid and vitamin $B_6$, when used together, have an additive effect and might be used as hair growth materials.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.271-275
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• 2008

Choline is important an organic compound for normal membrane function, acetylcholine synthesis, lipid transport, and methyl metabolism. In biological tissues and foods, there are multiple choline compounds that contribute to choline content. There are so many analytical methods for choline determination, such as radioisotopic, high-performance liquid chromatography, and gas chromatography/mass spectrometry. However, these existing methods are expensive, unmanageable, and time-consuming. In this study, we modified enzymatic method, which is applicable for the determination of choline in milk and infant formulas, and applied to bovine serum and muscle. The calibration curves were linear with higher correlation coefficients than 0.994. Recoveries obtained by calibration curves from the spiked bovine serum and muscle samples varied between 70.6 and 85.2%. The method may be suitable for use as a routine method in the determination of choline for biological tissue and food samples.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.141-150
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• 2018

Mussel byssal protein has strong adhesive capability even in wet surface. It has been reported that nine proteins in marine blue mussel, often referred to a representative mussel, contribute to form mussel byssal threads and plaques. DOPA containing two hydroxy groups called cathecol is recognized that it plays a major role in adhesion as well as cohesion process within byssal structure. In this paper, adhesion and cohesion mechanisms were introduced and evaluated by supportive literature published during last decade. Diverse applications of cathecol chemicals were also examined in terms of innovative adhesive, bioadhesive and challenging material for tissue engineering. It is noticeable that reconsideration of mussel proteins could provide the various opportunities as biomaterials.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.1
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• pp.23-29
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• 2011

Melatonin, which is the main product of the pineal gland, has well documented antioxidant and immune-modulatory effects. Macrophages produce molecules that are known to play roles in inflammatory responses. We conducted microarray analysis to evaluate the global gene expression profiles in response to treatment with melatonin in lipopolysaccharide (LPS) activated RAW 264.7 macrophage cells. In addition, eight genes were subjected to real-time reverse transcription polymerase chain reaction (RT-PCR) to confirm the results of the microarray. The cells were treated with LPS or melatonin plus LPS for 24 hr. LPS induced the up-regulation of 1073 genes and the down-regulation of 1144 genes when compared to the control group. Melatonin pretreatment of LPS-stimulated RAW 264.7 cells resulted in the down regulation of 241 genes and up regulation of 164 genes. Interestingly, among genes related to macrophage-mediated immunity, LPS increased the expression of seven genes (Adora2b, Fcgr2b, Cish, Cxcl10, Clec4n, Il1a, and Il1b) and decreased the expression of one gene (Clec4a3). These changes in expression were attenuated by melatonin. Furthermore, the results of real-time PCR were similar to those of the microarray. Taken together, these results suggest that melatonin may have a suppressive effect on LPS-induced expression of genes involved in the regulation of immunity and defense in RAW 264.7 macrophage cells. Moreover, these results may explain beneficial effects of melatonin in the treatment of various inflammatory conditions.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.235-238
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• 1995

모든 살아있는 조직은 표면전위(surface electropotentials)를 가지고 있으며, 이는 조직에 손상를 가져오는 상처가 발생되었을 때 그 상처를 치료하는데 큰 역할을 담당하고 있다. 즉, 상처부위에 인위적으로 표면전위의 특성을 가진 전기적인 자극을 가함으로서 상처의 치료효과를 높일 수 있으며, 그 중에서도 상처의 발생 직후에 음(-)의 전기자극을 가할 때 높은 치료효과를 나타내는 것으로 알려져 있다. 본 연구는 상처의 치료에 전기자극을 사용할 때, 자극의 특성 변화가 치료의 효과를 높일 수 있는가에 대한 기초 연구로서 수행하였다. 즉, 쥐의 복부부위를 일정한 크기로 절개하고, 그 부위에 1mA와 10mA의 자극 펄스를 지속시간을 10msec와 100msec로 변화하면서 $1\sim3$일간 제시한 후 상처가 치료된 정도를 비교하였다. 모든 자극이 끝난 후 상처부위에 대한 조직검사를 수행하여 육아조직(granulation tissue)의 상태를 관찰하였다. 그 결과 전기자극을 전혀 가하지 않은 그룹에 비하여 전기자극을 행한 그룹들의 육아조직에 있어서 그 형성 상태가 양호하였고, 괴사현상이 나타나지 않았으며, 염증의 정도가 낮게 나타났음을 발견하였다. 또한, 자극의 횟수를 증가할수록 전기자극으로 인한 치료의 효과가 크게 나타났음을 알 수 있었다. 그러나, 각 그룹 내에서 자극의 특성을 변화시키며 수행한 검사의 결과는 큰 차이를 보이지 않았다.

• Membrane Journal
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• v.14 no.2
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• pp.85-98
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• 2004

The situation of technology Predominance and the distribution of core technology were visually mapped thorough the investigation of technical trend during 20 years, which was provided with the analysis of patent information for the artificial skin. Therefore, it was expected that technology mapping by means of multilateral analysis method allowed a good grasp of current technology trend of the artificial skin and the subdivision into nation and a field of research presents the direction of R&D. In the early R&D stage of artificial skin, the preparation technology of filters implantable into the living body including nursing devices, bandages, and dressings or absorbent pads (A6IF-002/10) was on the rise in research field of artificial skin until 1980's. And then the materials technology for coating prostheses (A6l L-027/00)was leading the core technology of artificial skin. Also, Nowadays the fusion technology connected the material technology with the cultivation technology of undifferentiated human or animal cells/tissues including culture media (C l2N-005/00, C 12N-005/06) was highlighted all over the world.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.31.1-31.7
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• 2019

Background: To test the hypothesis that in profile smiling view, for ideal aesthetics, a tangent to the labial face of the maxillary central incisor crowns should be approximately parallel to the true vertical line and thereby perpendicular to the true horizontal line. Methods: An idealized female image was created with computer software and manipulated using the same software to construct an "ideal" female profile image with proportions, and linear and angular soft tissue measurements, based on currently accepted criteria for idealized Caucasian profiles. The maxillary incisor labial face tangent was altered in 5° increments from 70 to 120°, creating a range of images, shown in random order to 70 observers (56 lay people and 14 clinicians), who ranked the images from the most to the least attractive. The main outcome was the preference ranks of image attractiveness given by the observers. Results: The most attractive inclination of a tangent to the labial face of the maxillary incisor crowns in profile view in relation to the true horizontal line was 85°, i.e. 5° retroclined from a perpendicular 90° inclination. The most attractive range appears to be between 80 and 90°. Excessive proclination appeared to be less desirable than retroclination. Beyond 105° most observers recommend treatment. Conclusion: In natural head position, the ideal inclination of the maxillary incisor crown labial face tangent in profile view will be approximately parallel to the true vertical line and thereby approximately perpendicular to the true horizontal line.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.4
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• pp.308-315
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• 2004

Aim: The aim of this study was to investigate the mechanism of promoted skin wound healing in skin defects with primary cultured oral mucosal keratinocytes. Materials and methods: Thirty adult female nude mice weighing $20{\pm}2g$ were used for the experiment. Primary cultured and suspended oral mucosal keratinocytes, labeled with BrdU, were scattered onto $1.5cm{\times}1.5cm$ sized full thickness skin defects in the experimental group(N=15), and no grafts were placed the control group(N=15). They were sacrificed at 3 days, 1 week and 2 weeks after the treatment respectively. Histological examination of each wounds were performed to review the healing progress on measuring the length from the wound margin to regenerating epithelial front. The role of keratinocytes were assessed by double immunohistochemical staining with Anti-BrdU and Anti-cytokeratin AE1/3. Results: In the experimental group the wound was completely covered with regenerating epithelia in 2 weeks, but partially regenerated in the control group. The immunohistochemical studies unexpectedly reveal that most of regenerating epithelial cells were induced from marginal epithelium of the margin, not from the scattered keratinocytes. Conclusion: We could successfully confirm that graft of primary cultured oral mucosal keratinocytes promotes the regeneration of skin defects.