• Polymer(Korea)
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• v.36 no.4
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• pp.401-406
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• 2012

For bone regeneration from KUSA-A1 oesteoblast cells (KUSA), chitosan (CS) scaffolds possessing different surface properties, sponge-type (CSS) and nonwoven-type (CSNW), were manufactured. Surface area and pore size of CSNW were larger than those of CSS. On the other hand, the pore volume of CSNW was smaller than that of CSS. Cell attachment evaluation showed CSNW was more adequate then CSS, and this was attributed to the large surface area. For in vivo investigation, KUSA were seeded into CS scaffolds in wells followed by a week of cell culture. Obtained CS scaffolds with KUSA were implanted on the subcutaneous tissue of BALB/C nude mice. After surgery, implanted scaffolds were harvested and assayed by immunological staining. Network stability of CSS was better than that of CSNW, even if CSS scaffolds were destroyed between 4 and 6 weeks. Calcification was observed after 4 and 8 weeks for CSNW and CSS, respectively.

• Polymer(Korea)
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• v.39 no.3
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• pp.412-417
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• 2015

A critical element in tissue engineering approaches is a control of the mechanical properties of polymer scaffolds to regulate cell phenotype, which may lead to clinically successful tissue regeneration. In this study, we hypothesized that gel stiffness could be a key factor to manipulate adhesion and proliferation of different types of cells. RGD-modified alginate gels with various mechanical properties were prepared and used as a substrate for MC3T3-E1 and H9C2 cells. Adhesion and growth rate of MC3T3-E1 cells in vitro were increased in parallel with an increase of gel stiffness. In contrast, those of H9C2 cells were decreased. This approach to control the mechanical properties of polymer scaffolds depending on the cell types may find useful applications in the tissue engineering.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.10
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• pp.817-829
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• 2014

One of the main issues in tissue engineering has been the development of a three-dimensional (3D) structure, which is a temporary template that provides the structural support and microenvironment necessary for cell growth and differentiation into the target tissue. In tissue engineering, various biomaterials and their processing techniques have been applied for the fabrication of 3D structures. In particular, 3D printing technology enables the fabrication of a complex inner/outer architecture using a computer-aided design and manufacturing (CAD/CAM) system, and it has been widely applied to the fabrication of 3D structures for tissue engineering. Novel cell/organ printing techniques based on 3D printing have also been developed for the fabrication of a biomimetic structure with various cells and biomaterials. This paper presents a comprehensive review of the functional scaffold and cell-printed structures based on 3D printing technology and the application of this technology to various kinds of tissues regeneration.

• Journal of Chest Surgery
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• v.37 no.3
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• pp.220-227
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• 2004

The number of patients with coronary artery disease and peripheral vascular disease are increasing, and the need of small diameter vessel is also increasing. We developed small diameter artificial vessel and experimented in vivo. We got allogenic valve from mongrel dogs, and removed all cells from the allogenic valve. Then, we seeded autologous bone marrow cells onto the decellularized scaffold. After implantation of artificial vessel into the canine carotid artery, we performed angiography regularly. In case of vessel occlusion or at 8 weeks after operation, we euthanized dogs, and retrieved the implanted artificial vessels. Control vessels were all occluded except one (which developed aneurysmal dilatation). But autologous cell seeded vascular graft were patent by 4 weeks in one, by 6 in one and by 8 weeks in two. Histologic examination of patent vessel revealed similar structure to native artery. Tissue-engineered vascular graft manufactured with decellularized allogenic matrix and autologous bone marrow cells showed that tissue engineered graft had similar structure to native artery.

• Journal of the korean veterinary medical association
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• v.17 no.4
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• pp.34-37
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• 1981

FSC는 상시지방적을 보유하는 특성을 가지고 있으므로 지방섭취세포(fat-storing cell, FSC)라고 명명되어으며 유동에 노출하는 성세포, 내피세포와 달리 이 세포의 유동면은 교원직유와 내피세포에서 유래하는 윤랑선에 의하여 피복된다. 더욱이 이 세포는 각종 척추동물에 존재한다는 사실이 확인 되었으며 그 지방적은 동물의 종류에 따라 특유한 형을 구비하는 동시에 개체차가 없다. FSC는 이물탐식성이 없으며 지방적을 함유한 성세포와는 위치적, 기능적으로 다르다는 것이 증명되었다. 발생학적으로는 간엽세포에 속하며 유사분제에 의하여 증식능력을 가지고 있다. 이 세포에는 glycogen이 증명되며 모든 지방세포의 실험이 나타나는 성적에서와 유사하게 항시 지방을 합성하여 종의 특유한 형을 가진 지방적으로서 저장됨을 시사하였다. 전현적관륜에 의하여 FSC가 유동주위강(disse腔) 속에 있어 성세포, 내피세포와는 달리 유동에 노출하지 않고 항상 내피세포층과 교원직유에 의하여 유동에서 격리됨을 추정하였다. 이로 인하여 많은 학자들에 의하여 FSC가 승인을 받았다. 오늘날에는 유동을 둘러싸고 있는 상재세포가 내피세포, 성세포 및 FSC의 3종임이 인증이 되었다. 이 세포의 미세구조상의 특징은 기저막이 없는 공허한 세포로 보이나 항상지방적(空胞)을 보유하고 잘 발달한 조면소포체를 가지며 유동내피면에 따라 분기확산하는 돌기를 가지고 있다. 그리고 세포체는 유동주위강을 달리는 무수신경직유의 varicosity (사립체 및 신경결합소포를 함유한 신경종말)와의 사이에 adrenalin 작동성 synaps를 형성한다. FSC의 기능적 의의는 ㄱ, 간소엽내 교원직유형성에 참여 ㄴ. 유동내피하 돌기는 내피를 외측에서 지지하고 보강하며 또한 유동을 둘러싸고 연장하는 돌기는 수축하여 유동강을 축소한다. ㄷ. 지방을 저장하여 간세포의 energe원을 공급하며 VitaminA를 그 속에 저장한다. ㄹ. 간의 해독작용에 관여한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.148-152
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• 2000

To provide basic information on the integumentary system of the blenny, Pholis nebulosa, ultrastructures of epidermal and dermal layer were examined by means of the light and transmission electron microscope. The skin of the blenny consisted of epidermal and dermal layer. Epidermal layer consisted of supporting cell and unicellular gland. The supporting cells were classified into superficial cell, intermediated cell and basal cell, and the gland cells were classified into mucous secretory cell and club cell. The cytoplasm of supporting cells was divided into cortex and medullar part. In the cortex and medullar part, microfilaments and cell organelles were well developed, respectively. Superficial cell of epidermal layer was cuboidal and contained nucleus of horseshoe shape. Intermediated cell had a nucleus of irregular form and the electron density was higher than the other supporting cells, Basal cell was columnar, but nucleus was situated in the upper cytoplasm. Cell organelles of the basal cell were poor than the other supporting cells, but membrane interdigitations were well developed. The cytoplasm of mucous secretory cell had a well-developed ovoid secretory granules, which reacted to red with AB-PAS reaction. The club cell had a we31-developed round secretory granules and endoplasmic reticulum. figment cells were classified into two type. The one contained pigment granules of electron dense, and the other contained reflecting platelets. The cytoplasm of fibrocyte had n well developed rough endoplasmic reticulum.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.597-598
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• 2008

• Polymer Science and Technology
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• v.15 no.4
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• pp.430-437
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• 2004

인간 게놈 프로젝트 완성 및 간세포 (Stem cell) 발견으로 미래에는 현재 의학적 치료의 한계를 극복하는 의학적 혁명이 예상되고 있다. 간세포를 이용한 치료기술 개발을 위하여서는 균일한 간세포의 대량배양, 원하는 세포로의 균일한 분화, 면역학적 안전성 등이 매우 중요한 이슈가 되고 있으며 이의 해결을 위하여서는 생체적합성이 우수한 지지체의 개발이 기본이 되고 있다. (중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.11
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• pp.1111-1117
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• 2012

Implants for rhinoplasty should ideally be biocompatible and possess long-term stability after implantation. Silicone implants are most widely used for rhinoplasty. However, these implants suffer from problems related to high extrusion and infection rates. To minimize these complications, we propose a novel augmentation rhinoplasty technique using tissue engineering. To demonstrate its feasibility, a nasal-implant-shaped scaffold was designed using commercialized CAD software and fabricated using a Multi-head Deposition System, which is a solid freeform fabrication system that dispenses material. In vitro cell proliferation and chondrogenic differentiation tests were carried out using nasal septal chondrocytes.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.429-432
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• 2000

Chitosan scaffold is widely applied to drug delivery and tissue engineering. We have developed chitosan scaffolds, with various pore size, by differing freezing temperature and duration of ultraviolet (UV) irradiation, for reconstructing skin equivalent. Chitosan scaffold was coated with type I collagen, fibronectin and basic fibroblast growth factor (bFGF) in various combinations and concentrations, to evaluate the effect of extracellular matrix (ECM) and bFGF on cell adhesion, growth and differentiation of dermal fibroblasts. Human dermal fibroblasts, isolated from newborn foreskin and passaged between 3 and 5, were seeded on the top of scaffolds and cultivated for 2 weeks. We examined the morphology and the secretion of ECM of fibroblasts using scanning electron microsopy (SEM) and histochemistry. A stellate morphology of fibroblasts were seen in all groups. The scaffold coated with either type I collagen and bFGF or type I collagen and fibronectin, however, showed the best condtion of dermal fibroblasts, in that the highest cell number and ECM secretion were seen. On the contrary, scaffolds coated with all three factors, type I collagen, bFGF and fibronectin, showed lower number of cells and ECM secretion than scaffolds with two factors. There was a tendency of dose-dependence in all three factors for fibroblast growth and ECM secretion. In conclusion, we may suggest that chitosan scaffold coated with either type I collagen/bFGF or type I collagen/fibronectin could provide more favorable environment for the growth and differentiation of dermal fibroblasts.