• 한국정보기술학회 영문논문지
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• 제9권1호
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• pp.103-113
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• 2019

Motivation: Polymerized actin-based cytoskeletal structures are crucial in shape, dynamics, and resilience of a cell. For example, dynamical actin-containing ruffles are located at leading edges of cells and have a significant impact on cell motility. Other filamentous actin (F-actin) bundles, called stress fibers, are essential in cell attachment and detachment. For this reason, their mechanistic understanding provides crucial information to solve practical problems related to cell interactions with materials in tissue engineering. Detecting and counting actin-based structures in a cellular ensemble is a fundamental first step. In this research, we suggest a new method to characterize F-actin wrapping fibers from confocal fluorescence image stacks. As fluorescently labeled F-actin often envelope the fibers, we first propose to segment these fibers by diminishing an energy based on maximum flow and minimum cut algorithm. The actual actin is detected through the use of bilateral filtering followed by a thresholding step. Later, concave actin bundles are detected through a graph-based procedure that actually determines if the considered actin filament is enclosing the fiber.

• Asian-Australasian Journal of Animal Sciences
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• 제13권6호
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• pp.845-855
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• 2000

As high as 50% of pregnancies are known to fail and the majority of such losses occur during the peri-implantation period. For the establishment of pregnancy in mammalian species, therefore, implantation of the conceptus to the maternal endometrium must be completed successfully. Physiological events associated with implantation differ among mammals. In ruminant ungulates, an elongation of the trophohlast in early conceptus development is required before the attachment of the conceptus to the uterine endometrium. Moreover, implantation sites are restricted to each uterine caruncula where tissue remodeling, feto-maternal cell fusion and placentation take place in a coordinated manner. These unique events occur under strict conditions and are regulated by numerous factors from the uterine endometrium and trophoblast in a spatial manner. Interferon-tau (IFN-${\tau}$), a conceptus-derived anti-Iuteolytic factor, which rescues corpus luteum from its regression in ruminants, is particularly apt to play an important role as a local regulator in coordination with other factors, such as TGF-${\beta}$, Cox-2 and MMPs at the attachment and placentation sites.

• Clinical and Experimental Reproductive Medicine
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• 제49권4호
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• pp.248-258
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• 2022

Objective: This research investigated the effects of human chorionic gonadotropin (HCG)-producing peripheral blood mononuclear cells (PBMCs) on the implantation rate and embryo attachment in mice. Methods: In this experimental study, a DNA fragment of the HCG gene was cloned into an expression vector, which was transfected into PBMCs. The concentration of the produced HCG was measured using enzyme-linked immunosorbent assay. Embryo attachment was investigated on the co-cultured endometrial cells and PBMCs in vitro. As an in vivo experiment, intrauterine administration of PBMCs was done in plaque-positive female mice. Studied mice were distributed into five groups: control, embryo implantation dysfunction (EID), EID with produced HCG, EID with PBMCs, and EID with HCG-producing PBMCs. Uterine horns were excised to characterize the number of implantation sites and pregnancy rate on day 7.5 post-coitum. During an implantation window, the mRNA expression of genes was evaluated using real-time polymerase chain reaction. Results: DNA fragments were cloned between the BamHI and EcoRI sites in the vector. About 465 pg/mL of HCG was produced in the transfected PBMCs. The attachment rate, pregnancy rate, and the number of implantation sites were substantially higher in the HCG-producing PBMCs group than in the other groups. Significantly elevated expression of the target genes was observed in the EID with HCG-producing PBMCs group. Conclusion: Alterations in gene expression following the intrauterine injection of HCG-producing PBMCs, could be considered a possible cause of increased embryo attachment rate, pregnancy rate, and the number of implantation sites.

• Human Ecology Research
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• 제52권5호
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• pp.519-528
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• 2014

This study explores how the main variables of youth going through a transition period (parents' nurturing behavior, the youth's self-esteem and ego resilience, the peer group relationships) affect the youth's school adjustment. It also analyzes the effects of theses variables on the youth's dependence on cell phones, which are considered a necessity in modern society. This research is verified by using a structure model verification method based on data from the Korean Children Youth Panel Study. According to the research, first, 1st-year students in middle school show better adjustment to their school life and less dependence on cell phones when they have a stronger sense of self-esteem and ego resilience; further, it is revealed that cell phone dependence has an indirect influence on the school life of these children. Second, they tend to show better adjustment to their school life and less dependence on cell phones when their parents' nurturing behaviors are more positive. Third, these children tend to depend more on cell phones when they have a positive peer group relationship, Moreover, cell phone dependence has an indirect influence on their school life. When considering the impact of cell phone to youth in modern society, need to prepare proper training program for correct uses and preventing from addiction.

• 대한치과보철학회지
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• 제50권1호
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• pp.44-52
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• 2012

연구 목적: 본 실험은 거친 표면으로 유의성 있는 줄기세포반응을 나타냈던 4 가지의 티타늄 표면 위에 rhBMP-2를 코팅했을 때 어떤 유의한 줄기세포반응(세포부착, 증식, 분화)이 나타나는지 비교 분석함으로 rhBMP-2 코팅을 위한 가장 적절한 표면을 평가하기 위해 시행되었다. 연구 재료 및 방법: 대조군인 기계절삭표면(machined surface)과 실험군인 양극산화(anodized), RBM, SLA 표면에 rhBMP-2를 코팅한 후 코팅하지 않은 표면과 같이 8가지 표면 위에 인간줄기세포를 배양하였다. 배양 후 24시간 후 SEM을 통해 줄기세포의 부착을 평가하였고 배양 3, 7, 14일후MTT와 ALP 검사를 통해 줄기세포의 증식과 분화반응을 평가하였다. 그리고 배양 7일후RT-PCR 검사를 통해 Type I collagen, osteocalcin, osteopontin의 유전자 발현의 변화를 평가하였다. 결과: SEM 평가에서 4가지 rhBMP-2 표면이 코팅하지 않은 표면에 비해 세포부착 면적이 넓고 긴밀하며 세포돌기가 더 많이 관찰되었다. 양극산화 rhBMP-2코팅표면에서 가장 두드러지게 관찰되었다. MTT 검사에서 크게 의미 있는 차이는 나타나지 않았다. ALP검사에서 양극산화 rhBMP-2코팅 표면은 대조군과 비교해서 (3, 14일) 또 RBM rhBMP-2 코팅 표면과 비교해서 (14일) 유의성 있는 ALP 활성도의 증가를 나타내었다(P<.05). RT-PCR 검사에서 osteocalcin과 osteopontin의 유전자 발현은 양극산화 rhBMP-2코팅 표면에서 높게 나타났다. 결론: 양극산화 rhBMP-2코팅표면이 줄기세포의 부착과 분화실험에서 대조군표면과 rhBMP-2를 코팅한 기계절삭표면이나 RBM 표면에 비해 유의성 있는 증가를 나타냈다(P<.05).

• Journal of Periodontal and Implant Science
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• 제47권6호
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• pp.402-415
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• 2017

Purpose: The aim of this study was to determine the effects of patterned human periodontal ligament stem cell (hPDLSC) sheets fabricated using a thermoresponsive substratum. Methods: In this study, we fabricated patterned hPDLSC sheets using nanotopographical cues to modulate the alignment of the cell sheet. Results: The hPDLSCs showed rapid monolayer formation on various surface pattern widths. Compared to cell sheets grown on flat surfaces, there were no significant differences in cell attachment and growth on the nanopatterned substratum. However, the patterned hPDLSC sheets showed higher periodontal ligamentogenesis-related gene expression in early stages than the unpatterned cell sheets. Conclusions: This experiment confirmed that patterned cell sheets provide flexibility in designing hPDLSC sheets, and that these stem cell sheets may be candidates for application in periodontal regenerative therapy.

• 대한기계학회논문집B
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• 제34권1호
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• pp.83-87
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• 2010

HL-1 세포(심근세포주)는 AT-1 쥐의 심방암세포에서 추출한 심근세포로써, 특별한 약물의 주입 없이도 맥동현상을 보이며, 여러 번의 계대 배양 후에도 그 수축성을 잃지 않는 특성이 있어 바이오센서에 적용하기 용이하다. 본 연구에서는 세포 외 기질물질(ECM: extra cellular matrix)의 영향에 따른 HL-1 의 성장과 형질변화를 분석하였다. HL-1 세포를 ECM 이 처리되지 않은 표면과 서로 다른 3 가지 ECM 인 gelatin 수용액, fibronectin 수용액 및 gelatin 과 fibronectin 의 혼합 수용액으로 처리된 표면에 배양하여 세포와 ECM의 상호작용 및 세포의 성장을 관찰하였다. 세포 배양 직후부터 배양후 4 일까지의 세포의 변화를 형광 면역 염색법 (immunostaining)을 이용하여 분석하였다. 세포 증식은 Hoechst 와 EthD-1 을 통해 관찰하였고, DAPI 염색으로 세포핵을 phalloidin 염색을 통해 F-actin 을 관찰하였다. fibronectin 수용액을 ECM으로 사용하였을 때, 세포 성장 및 형질유지에 가장 효과적인 것으로 나타났다. 본 연구의 결과는 HL-1 세포와 ECM 의 상호 작용 및 세포의 성장을 이해하는 데 기초자료로 활용될 수 있으리라 기대된다.

• 환경생물
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• 제27권1호
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• pp.88-94
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• 2009

안토시아닌(Anthocyanin)은 플라보노이드계 화합물의 한 부류로 항산화, 항암 및 항궤양, 항당뇨, 중금속해독, 시력보호, 콜레스테를 저하 등의 다양한 생리활성을 가지는 것으로 보고되어 있다. 죽상경화과정은 염증성 사이토카인의 분비 또는 혈관손상으로 인한 백혈구의 부착과 이동을 통해 시작된다. 본 연구는 이러한 죽상경화의 초기과정에서 안토시아닌 혼합물 중 single compound인 delphinidin chloride (DC) 인간혈관 내피세포주(HUVEC, human umbilical vein endothelial cell line)에서 백혈구 부착과 관련이 있는 ICAM-1 (Intraceliular Adhesion Molecule-1)과 VCAM-1 (Vascular Adhesion Molecule-1) 발현에 미치는 영향에 대해 조사하였다. 세포독성이 없는 농도에서 TNF-$\alpha$에 의해 유도된 혈관 내피세포에 대한 단핵구의 부착정도를 측정하기 위해 monocyte-endothelial cell adhesion assay와 광학현미경을 이용한 형태학적 관찰을 한 결과 DC가 처리농도 의존적으로 부착을 억제하였다. 내피세포로부터 TNF-$\alpha$에 의해 유도된 세포부착 분자인 VCAM-1과 ICAM-1의 발현에 대한 영향을 western blot analysis 및 RT-PCR방법으로 비교 분석한 결과 VCAM-1과 ICAM-1의 단백질과 mRNA수준에서의 발현이 농도 의존적으로 감소되었다. 이러한 결과들을 종합해 볼 때 안토시아닌 중에서 DC를 실험한 결과 DE는 TNF-$\alpha$에 의해 유도된 내피세포의 ICAM-1과 VCAM-1 발현 억제효과를 확인할 수 있었다.

• 대한치과보철학회지
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• 제43권3호
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• pp.393-408
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• 2005

Statement of problem. In the process of bone formation, titanium (Ti) surface roughness is an important factor modulating osteoblastic function. Purpose. This study was carried out to determine the effect of different Ti surface on biologic responses of a human osteoblast-like cell line (MG63). Materials and methods. MG63 cells were cultured on S (smooth), SLA (sandblasted largegrit & acid etching), HA (hydroxyapatite) Ti. The morphology and attachment of the cells were examined by SEM. The cDNAs prepared from total RNAs of MG63 were hybridized to a human cDNA microarray (1,152 elements). Results. The appearances of the surfaces observed with SEM were different in the three types of dental substrates. The surface of SLA and HA were shown to be rougher than S. MG63 cells cultured on SLA and HA were cell-matrix interaction. In the expression of genes involved in osseointegration, upregulated genes were bone morphogenetic protein, Villin, Integrin, Insulin-like growth factors in different surfaces. Downregulated genes were fibroblast growth factor receptor 4, Bcl 2-related protein, collagen, CD4 in different surfaces. Conclusion. The attachment and expression of key osteogenic regulatory genes were enhanced by surface roughness of the dental materials.

• 구강회복응용과학지
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• 제20권1호
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• pp.31-41
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• 2004

The osseointegration in implant therapy is achieved following general wound healing mechanism. Platelet play a major role in wound healing process. In addition to blood clot formation, they secrete many growth factors which regulate the attachment, proliferation and differentiation of nearly all cell types. The use of these growth factors is now known to be very effective methods to improve the cellular activity. Platelet-rich plasma which is made with the newly developed technique concentrating platelets 3-folds or more is also proven to be very effective method to stimulate and accelerate the healing of bone and soft tissue. Previous study proved that platelet-rich plasma enhanced the cellular attachment by inducing fibronectin, vitronectin from osteoblast. So, this study was aimed to investigate the effect of platelet-rich plasma on the cellular proliferation and differentiation in vitro. The effect on the proliferation was evaluated by MTT assay. To evaluate autocrine and paracrine effect, conditioned medium was made and compared. By measuring alkaline phosphatase activity, the effect on the cellular differentiation was evaluated. The results were as following: The cellular proliferation of osteoblast cell line increased depending on the concentration of platelet-rich plasma and conditioned medium. The alkaline phosphatase activity increased depending on the concentration of platelet-rich plasma and conditioned medium. These findings imply that platelet-rich plasma enhance the cellular proliferation and differentiation and maximize the cellular activity by using the autocrine and paracrine effect.