• Biomedical Science Letters
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• v.15 no.2
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• pp.113-118
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• 2009

Actin cytoskeletal architecture is believed to be a crucially important modulator of chondrocyte phenotype. 2DG(2-Dexoy-D-glucose) induces reorganization of actin cytoskeletal architecture in chondrocytes. In this study, we have investigated the effects of 2DG on dedifferentiation and inflammation via reorganization of cytoskeletal architecture in rabbit articular chondrocytes, with a focus on p38 kinase pathway. Treatment of 2DG alone reduced type II collagen and COX-2 expression in chondrocytes. But, 2DG reduced type II collagen was recovered by CD, disruptor of actin cytoskeletal architecture, whereas did not affect on COX-2 expression and production of $PGE_2$ compared with 2DG alone treated cells. Treatment of 2DG with JAS, inducer of cytoskeletal architecture polymerization, accelerated reduction of type II collagen expression and synthesis of proteoglycan but did not affect on COX-2 expression and production of $PGE_2$. Also, 2DG stimulated activation of p38 kinase. This result showed that 2DG regulates type II collagen but not cyclooxygenase-2 expression through reorganization of cytoskeletal architecture via p38 kinase pathway in rabbit articular chondrocytes.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.1
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• pp.89-102
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• 2019

Collagen can be used in building artificial skin replacements for treatment of burns and towards the reconstruction of bone as well as researching cell behavior and cellular interaction. The strength of collagen in connective tissue rests on the characteristics of collagen fibers. 3D confocal imaging of collagen fibers enables the characterization of their spatial distribution as related to their function. However, the image stacks acquired with confocal laser-scanning microscope does not clearly show the collagen architecture in 3D. Therefore, we developed a new method to reconstruct, visualize and characterize collagen fibers from fluorescence confocal images. First, we exploit the tensor voting framework to extract sparse reliable information about collagen structure in a 3D image and therefore denoise and filter the acquired image stack. We then propose to segment the collagen fibers by defining an energy term based on the Hessian matrix. This energy term is minimized by a min cut-max flow algorithm that allows adaptive regularization. We demonstrate the efficacy of our methods by visualizing reconstructed collagen from specific 3D image stack.

• YAKHAK HOEJI
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• v.51 no.1
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• pp.7-12
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• 2007

Hepatic cirrhosis is an important feature of chronic liver disease. Liver cirrhosis is characterized by hyperaccumulation of fibrous tissue components and is commonly observed in latter or terminal states of chronic hepatic disease. The antifibrotic effects on liver cirrhosis by oriental herbs extraction material were examined in bile duct ligated rats. Oriental herbs extraction (0.99 mg/kg rat weight/day) was administrated to cirrohotic rats for 4 weeks. Liver collagen content of bile duct ligated rats was significantly increased. And liver histology showed collagen fiber deposition was increased as well as the normal architecture was lost with large zone of necrosis being observed. Herbs extraction administrated rats showed significantly decreased liver collagen content, accumulation of collagen fiber in histological analysis, and biochemical markers of hepatic diseases. Those results demonstrate the usefulness of herbs extraction materials as an antifibrotic agent for liver cirrhosis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1409-1410
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• 2011

• Advances in Traditional Medicine
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• v.2 no.2
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• pp.94-100
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• 2002

Liver cirrhosis is characterized by hyperaccumulation of fibrous tissue components and is commonly observed in latter or terminal states of chronic hepatic diseases. In this study, the antifibrotic effects of GLM001 on liver cirrhosis were examined in bile duct ligated rats and patients with hepatic diseases. GLM001 (250 mg/kg rat weight/ day) was administrated to cirrhotic rats for 4 weeks and to humans for 14 weeks. Bile duct ligated rats significantly increased liver collagen content and biochemical markers of hepatic injury. Liver histology showed collagen fiber deposition was increased and the normal architecture was lost with large zones of necrosis being observed frequently. GLM001 administrated rats showed significantly decreased liver collagen content, and accumulation of collagen fiber in histological analysis. Patients, who were treated with GLM001, showed decreases in biochemical markers of hepatic diseases. These results demonstrate the usefulness of GLM001 as an antifibrotic agent for liver cirrhosis.

• Restorative Dentistry and Endodontics
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• v.35 no.3
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• pp.211-221
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• 2010

Proteoglycan is highly hydrophilic and negatively charged which enable them attract the water. The objective of study was to investigate the effects of Proteoglycan on microtensile bond strength of dentin adhesives and on architecture of dentin collagen matrix of acid etched dentin by removing the chondroitin sulphate attached on Proteoglycan. A flat dentin surface in mid-coronal portion of tooth was prepared. After acid etching, half of the specimens were immersed in 0.1 U/mL chondroitinase ABC (C-ABC) for 48 h at $37^{\circ}C$, while the other half were stored in distilled water. Specimens were bonded with the dentin adhesive using three different bonding techniques (wet, dry and re-wet) followed by microtensile bond strength test. SEM examination was done with debonded specimen, resin-dentin interface and acid-etched dentin surface with/without C-ABC treatment. For the subgroups using wet-bonding or dry-bonding technique, microtensile bond strength showed no significant difference after C-ABC treatment (p > 0.05). Nevertheless, the subgroup using rewetting technique after air dry in the Single Bond 2 group demonstrated a significant decrease of microtensile bond strength after C-ABC treatment. Collagen architecture is loosely packed and some fibrils are aggregated together and relatively collapsed compared with normal acid-etched wet dentin after C-ABC treatment. Further studies are necessary for the contribution to the collagen architecture of noncollagenous protein under the various clinical situations and several dentin conditioners and are also needed about long-term effect on bond strength of dentin adhesive.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.229.2-230
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• 2003

Extracellular matrix(ECM) is composed of the ground materials(proteoglycan) and nano size diameter fibrous proteins(ex. collagens) that together form a composite-like structure. In this study, fibrous scaffold with biomimetic architecture based on collagen nanofibers interpenetrated in PLGA/chitosan microfibrous matrix. Chitosan was selected for its structure similarity to glycosaminoglycan and neutralizing capacity for PLGA acidic metabolite. Collagen nanofiber were prepared by electrospinning. (omitted)

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.335-338
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• 1996

We attempted to reconstruct basement membrane (BM) in between the epidermal compartment and dermal compartment in the artificial skin preparation and examine its effect on the skin architecture as well as on the epidermal differentiation. Laminin, one of the component of BM, stimulate the migration of the basal cells but type IV collagen which is a major component of the mechanical network of BM did not stimulate epidermal migration. However laminin in the presence of type IV collagen at a 1:1 molar ratio did not stimulate epidermal migration but provide nice demarcation between epidermis and dermis. This mixture of laminin and type IV collagen enhanced epidermal differentiation in the artificial skin based on the morphological observation as well as biochemical criteria. The epidermal acquirement of migratory ability on the laminin-rich substrate suggest that this type of unbalance in the expression of the components of BM may prevail in the area of healing tissue and the invasive transition of the tumor. The result in this study provide the technical improvement in the artificial skin preparation and further application of this technique for the reconstruction of other bio-artificial organ.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.1
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• pp.33-45
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• 2015

To engineer tissue-like structures, cells are required to organize themselves into three-dimensional networks that mimic the native tissue micro-architecture. Here, we present agarose-based multi-well platform incorporated with electrical stimulation to build skeletal muscle-like tissues in a facile and highly reproducible fashion. Electrical stimulation of C2C12 cells encapsulated in collagen/matrigel hydrogels facilitated the formation 3D muscle tissues. Consequently, we confirmed the transcriptional upregulations of myogenic related genes in the electrical stimulation group compared to non-stimulated control group in our multi-well 3D culture platform. Given the robust fabrication, engineered muscle tissues in multi-well platform may find their use in high-throughput biological studies drug screenings.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.3-23
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• 2017

The achievement of tissue engineering can be highly depending on the capability to generate complicated, cell seeded three dimensional (3D) micro/nano-structures. So, various fabrication techniques that can be used to precisely design the architecture and topography of scaffolding materials will signify a key aspect of multi-functional tissue engineering. Previous methods for obtaining scaffolds based on top-down are often not satisfactory to produce complex micro/nano-structures due to the lack of control on scaffold architecture, porosity, and cellular interactions. However, a bioprinting method can be used to design sophisticated 3D tissue scaffolds that can be engineered to mimic the tissue architecture using computer aided approach. Also, in recent, the method has been modified and optimized to fabricate scaffolds using various natural biopolymers (collagen, alginate, and chitosan etc.). Variation of the topological structure and polymer concentration allowed tailoring the physical and biological properties of the scaffolds. In this presentation, the 3D bioprinting supplemented with a newly designed plasma treatment for attaining highly bioactive and functional scaffolds for tissue engineering applications will be introduced. Moreover, various in vivo and in vitro results will show that the fabricated scaffolds can carry out their structural and biological functionality.