• Polymer(Korea)
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• v.39 no.1
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• pp.144-150
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• 2015

Gellan gum as a natural polysaccharide has good heat resistance, acid resistance and enzymes resistance. However, one of the drawbacks of gellan gum might be the lower mechanical strength. In this work, gellan gum scaffolds were mixed with poly(lactic-co-glycolic acid) (PLGA) microsphere in order to improve mechanical properties. The gellan gum scaffolds with various contents of PLGA microsphere were prepared for the regeneration of disc tissues. To evaluate the mechanical strength of hybrid structure of gellan gum and PLGA microsphere, compression strength of the fabricated scaffolds was measured. MTT analysis, SEM observation, histological evaluation and RT-PCR were performed to confirm the effect on the cell growth and extracellular matrix secretion. As a result, it showed the best cell proliferation and extracellular matrix secretion in gellan gum sponge containing 50% PLGA microspheres. In conclusion, this study confirmed that the hybrid structure of gellan gum and PLGA microspheres was found suitable in regeneration of the intervertebral disc.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.3
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• pp.286-291
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• 2017

Maintaining the blood supply of the interdental alveolar bone is crucial for preserving the interdental papilla. Rebuilding the interimplant papilla between adjacent implants is more difficult than rebuilding the interdental papilla between the natural tooth and implant. Therefore, preserving the interimplant tissue is necessary when adjacent implants are closely placed. In this case report, three effective methods for maintaining the surrounding tissue, namely strategic serial extraction, immediate implantation, and provisionalization of adjacent maxillary central incisors, were performed. The marginal gingiva and interimplant papilla were well maintained for 24 months.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.1
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• pp.48-54
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• 2020

In the case of crown-root fracture due to traumatic injury in anterior tooth and the fracture margin is located subgingivally, forced eruption has been proposed for the reconstruction of deficient bone and soft tissue. Forced eruption is one of the easiest orthodontic approaches that can have an acceptable outcome and prognosis, and has a low incidence of relapse. However, using heavy forces or very fast movements can also cause tissue damage or ankylosis. The following case reports present forced eruption as treatment option of crown fracture in maxillary anterior teeth.

• KSBB Journal
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• v.17 no.3
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• pp.283-289
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• 2002

The present study was aimed at investigating the metabolic regulation of insulin-like growth factor-I(IGF-I) expression in fasting animals. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA from control, 4d-fasting, and 2d-fasting-refed rats. The levels of IGF-I transcripts were reduced in 4d-fasting than in control by decreasing its transcriptional rate, which was measured through nuclear nun-on assay. DNase I footprinting, which was performed using nuclear extracts from fasting rat, demonstrated protein binding to a sequence that extended from +179 to +210 (termed region B). These data suggest that the expression of IGF-I is transcriptionally regulated through DNA-liver enriched protein binding in a sequence which is located downstream from major transcription initiation site of IGF-I gene.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.98-100
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• 2003

Synthetic polymers such as PET and ePTFE have widely been used for artificial vascular patches. However, these materials cannot function for a long term as blood vessel due to thrombotic occlusion and calcification. To overcome this limitation, a biocompatible vascular patch was developed using stem cell and tissue engineering approach. Autologous bone marrow mesenchymal stem cells were differentiated into vascular endothelial cells and smooth muscle cells. These cells were seeded onto collagen patch matrices. The matrices were anastomosed to abdominal arteries in canine models. Prior to implantation, histological and scanning electron microscopical examination revealed stem cell adhesion and growth on the matrices. At 3 weeks, the implanted vascular patches were patent. Histological examination showed the regeneration of endothelium, media and adventitia in the grafts. Cell tracing analysis using fluorescent reagent showed that labeled stem cells were present in the implanted grafts and contributed to the regeneration of vascular tissues. This study may help us develop a tissue-engineered vascular patch appropriate for clinical applications.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.202-206
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• 2008

Recently, as high level of interest for the city regeneration, large-scale projects are planned or being performed such as reconstruction project. These mesa-projects have different characteristics from a single project in the design phase. It is a number of companies involved in design phase of mega-project and principal decision-making entity manage the project from the initial stage of an ongoing business by coordinating an opinions between design companies. The absence of a decision making support system reflected those characteristic causes a variety of problems such as a loss of cost and schedule. Therefore the final object of this paper is to propose a decision making support tool and system interface.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.331-338
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• 2004

This study was conducted to obtain the virus free plants through meristem culture of carnation (Dianthus caryophillus). Four cultivars (Roland, Desio, Casha, Giant Gipsy) were collected for materials. The apical meristem 0.3-0.5mm in size was cultured on MS medium containing 3% sucrose, 0.9% agar at pH 5.8 with various plant growth regulators for 7 weeks. Among the cultivars, Giant Gipsy had a better response than other cultivars in shoot formation and reduced vitrification. Callus induction and shoot formation from the meristem culture were influenced by the various kinds of cytokine. Kinetin supplement was the most effective for shoot formation and NAA addition was good for callus induction among the treatments. Total 115 plantlets derived from apical meristem culture were checked for CarMV and CarRSV infection by ELISA test. Among them, 40 plantlets (34.8%) were infected with CarMV but not detected for CarRSV.

• Korean Journal of Plant Tissue Culture
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• v.24 no.2
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• pp.119-124
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• 1997

Plantlets were regenerated from various explants (shoot tip, leaf blade, petiole and root segments) via organogenesis and/or somatic embryogenesis from Armoracia rusticana(Lam) Gaerth., Mey, et Scherb.. Shoot regeneration rate from callus was highest on the MS mediums supplemented with 0.5 ㎎/L IAA, 5.0㎎/L BA and 10.0㎎/L spermine. A Low frequency of regeneration occurred on hormone-free MS medium. Multiple shooks were regenerated at a pH of 4.0 to 8.0 on MS medium supplemented with 1.0 ㎎/L BA and 0.1 ㎎/L NAA. Polyamines promoted shoot- and root-formation by 2 to 4 times normal, Specific proteins associated with organogenesis were identified. Somatic embryogenesis occurred directly from the leaf blade, petiole and root segments cultured on MS medium with 2.0 ㎎/L BA and 2.0 ㎎/L BA and 2.0 ㎎/L NAA. Three types of regeneration in A, rusticana were clearly established, which could be applied to the study of morphogenesis and genetics at cell, tissue and organ levels.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.3
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• pp.219-226
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• 2011

The Echinacea, which has been commonly known as a species of composite herb of dicotyledonous plant, has been used in native American traditional medicine for the treatment of diseases like colds or other infections in North America. We artificially cultured the adventitious roots of Echinacea angustifolia using the bioreactor culture system from Echinacea angustifolia and evaluated the efficacy as a cosmetic ingredient for skin care. Several studies previously have reported neogenesis, wound healing and inflammatory inhibition effect of Echinacea angustifolia but other efficacies were not well known. In the present study, we investigated the cosmetic efficacy to know applicable value of adventitious roots cultured from Echinacea angustifolia as a cosmetic ingredient. The adventitious roots extract of Echinacea angustifolia has superior anti-oxidant effect and matrix metalloproteinase-2 inhibitory effect, compared to natural Echinacea angustifolia. These results indicate that the adventitious roots extract cultured from Echinacea angustifolia presents a new possibility of being applicable to skin care and anti-wrinkle products as a cosmetic ingredient.

• Tuberculosis and Respiratory Diseases
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• v.58 no.1
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• pp.54-58
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• 2005

Background : To evaluate the role of estrogen and progesterone in the carcinogenesis of NSCLC, IHC studies for the expression of the receptors of estrogen and progesterone have been performed with inconsistent results. Recently the TMA method has been developed and has become recognized as a useful and rapid method for extensively analysing molecular markers at the gene and protein level. We have investigated their expressions in the tissue from NSCLC using the microarray method. Methods : The TMA construction was made with 70 formalinfixed, paraffin-embedded tissues of NSCLC. After heat-induced epitope retrieval, IHC staining on primary tissues of NSCLC was performed with the monoclonal antibodies, ER1D5 and PR1A6. Results : Our sample of 70 consisted of 74% men and 26% women. Of the patients, 49% were current smokers, 27% were non-smokers and 24% were former smokers. By histologic classification, 34 patients had squamous cell carcinoma, 24 had adenocarcinoma, 9 had adenosquamous cell carcinoma, and 3 had other carcinomas. No cancer cells were immunostained with these monoclonal antibodies in any primary tissues of NSCLC. Conclusions : No expression of neither of the two receptors was found in any of the lung cancer tissues. This suggests that adequate genetic variants for IHC staining need to be developed for NSCLC.