• Journal of Periodontal and Implant Science
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• v.53 no.3
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• pp.207-217
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• 2023

Purpose: Non-crosslinked and crosslinked collagen membranes are known to exhibit distinct degradation characteristics, resulting in contrasting orientations of the adjacent tissues and different biological processes. The aim of this study was to conduct a histomorphometric assessment of non-crosslinked and crosslinked collagen membranes regarding neovascularization, tissue integration, tissue encapsulation, and biodegradation. Methods: Guided bone regeneration was performed using either a non-crosslinked (BG) or a crosslinked collagen membrane (CM) in 15 beagle dogs, which were euthanized at 4, 8, and 16 weeks (n=5 each) for histomorphometric analysis. The samples were assessed regarding neovascularization, tissue integration, encapsulation, the remaining membrane area, and pseudoperiosteum formation. The BG and CM groups were compared at different time periods using nonparametric statistical methods. Results: The remaining membrane area of CM was significantly greater than that of BG at 16 weeks; however, there were no significant differences at 4 and 8 weeks. Conversely, the neovascularization score for CM was significantly less than that for BG at 16 weeks. BG exhibited significantly greater tissue integration and encapsulation scores than CM at all time periods, apart from encapsulation at 16 weeks. Pseudoperiosteum formation was observed in the BG group at 16 weeks. Conclusions: Although BG membranes were more rapidly biodegraded than CM membranes, they were gradually replaced by connective tissue with complete integration and maturation of the surrounding tissues to form dense periosteum-like connective tissue. Further studies need to be performed to validate the barrier effect of the pseudoperiosteum.

• Journal of Periodontal and Implant Science
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• v.50 no.5
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• pp.327-339
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• 2020

Purpose: The purpose of this study was to examine the local tissue reactions associated with 3 different poly(lactic-co-glycolic acid) (PLGA) prototype membranes and to compare them to the reactions associated with commercially available resorbable membranes in rats. Methods: Seven different membranes-3 synthetic PLGA prototypes (T1, T2, and T3) and 4 commercially available membranes (a PLGA membrane, a poly[lactic acid] membrane, a native collagen membrane, and a cross-linked collagen membrane)-were randomly inserted into 6 unconnected subcutaneous pouches in the backs of 42 rats. The animals were sacrificed at 4, 13, and 26 weeks. Descriptive histologic and histomorphometric assessments were performed to evaluate membrane degradation, visibility, tissue integration, tissue ingrowth, neovascularization, encapsulation, and inflammation. Means and standard deviations were calculated. Results: The histological analysis revealed complete integration and tissue ingrowth of PLGA prototype T1 at 26 weeks. In contrast, the T2 and T3 prototypes displayed slight to moderate integration and tissue ingrowth regardless of time point. The degradation patterns of the 3 synthetic prototypes were similar at 4 and 13 weeks, but differed at 26 weeks. T1 showed marked degradation at 26 weeks, whereas T2 and T3 displayed moderate degradation. Inflammatory cells were present in all 3 prototype membranes at all time points, and these membranes did not meaningfully differ from commercially available membranes with regard to the extent of inflammatory cell infiltration. Conclusions: The 3 PLGA prototypes, particularly T1, induced favorable tissue integration, exhibited a similar degradation rate to native collagen membranes, and elicited a similar inflammatory response to commercially available non-cross-linked resorbable membranes. The intensity of inflammation associated with degradable dental membranes appears to relate to their degradation kinetics, irrespective of their material composition.

• The Journal of the Korean dental association
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• v.29 no.6 s.265
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• pp.463-465
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• 1991

I.T.I. Hollow Screw Implant는 새로운 I.T.I. Bonefit의 槪念의 일부를 이루었으며, 從來의 I.T.I. IMPLANT의 10년 以上의 臨床經驗에 기초하고 있다. I.T.I. Implant의 特徵은 몇가지 있으나, 그 중에서도 特記할 만한 것은 1回法의 外科術式이라고 할 수 있다. 本論文에서는 I.T.I. Hollow Screw Implant를 사용한 部分的齒牙欠損患者의 治療에 대한 術前評價와 外科術式에 대하여 論하고저 한다. 植立된 111개 Implant중 110개가 合倂症을 나타내지 않고 Tissue-Integration을 達成했으며, 그 밖의 1개는 失敗했다. 이러한 結果는 1回法인 I.T.I. Hollow Screw Implant가 Tissue-Integration으로서 成功率이 높은 것을 証明하고 있다.

• The Journal of the Korean dental association
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• v.29 no.7 s.266
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• pp.535-542
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• 1991

I.T.I. Hollow Screw Implant는 새로운 I.T.I. Bonefit의 槪念의 일부를 이루었으며, 從來의 I.T.I. IMPLANT의 10년 以上의 臨床經驗에 기초하고 있다. I.T.I. Implant의 特徵은 몇가지 있으나, 그 중에서도 特記할 만한 것은 1回法의 外科術式이라고 할 수 있다. 本論文에서는 I.T.I. Hollow Screw Implant를 사용한 部分的齒牙欠損患者의 治療에 대한 術前評價와 外科術式에 대하여 論하고저 한다. 植立된 111개 Implant중 110개가 合倂症을 나타내지 않고 Tissue-Integration을 達成했으며, 그 밖의 1개는 失敗했다. 이러한 結果는 1回法인 I.T.I. Hollow Screw Implant가 Tissue-Integration으로서 成功率이 높은 것을 証明하고 있다.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.366-370
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• 2005

Tissue microarry is one of the high throughput technologies in the post-genomic era. Using tissue microarray, the researchers are able to investigate large amount of gene expressions at the level of DNA, RNA, and protein The important aspect of tissue microarry is its ability to assess a lot of biomarkers which have been used in clinical practice. To manipulate the categorical data of tissue microarray, we applied Bayesian network classifier algorithm. We identified that Bayesian network classifier algorithm could analyze tissue microarray data and integrating prior knowledge about gastric cancer could achieve better performance result. The results showed that relevant integration of prior knowledge promote the prediction accuracy of survival status of the immunohistochemical tissue microarray data of 18 tumor suppressor genes. In conclusion, the application of Bayesian network classifier seemed appropriate for the analysis of the tissue microarray data with clinical information.

• BMB Reports
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• v.56 no.1
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• pp.32-42
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• 2023

Heart disease is one of the major life-threatening diseases with high mortality and incidence worldwide. Several model systems, such as primary cells and animals, have been used to understand heart diseases and establish appropriate treatments. However, they have limitations in accuracy and reproducibility in recapitulating disease pathophysiology and evaluating drug responses. In recent years, three-dimensional (3D) cardiac tissue models produced using tissue engineering technology and human cells have outperformed conventional models. In particular, the integration of cell reprogramming techniques with bioengineering platforms (e.g., microfluidics, scaffolds, bioprinting, and biophysical stimuli) has facilitated the development of heart-on-a-chip, cardiac spheroid/organoid, and engineered heart tissue (EHT) to recapitulate the structural and functional features of the native human heart. These cardiac models have improved heart disease modeling and toxicological evaluation. In this review, we summarize the cell types for the fabrication of cardiac tissue models, introduce diverse 3D human cardiac tissue models, and discuss the strategies to enhance their complexity and maturity. Finally, recent studies in the modeling of various heart diseases are reviewed.

• Journal of Plant Biotechnology
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• v.1 no.2
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• pp.85-90
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• 1999

In order to protect fungal diseases, leaf disc explants of Solanum tuberosum cultivar, Belchip, was infected with an Agrobacterium MP90 strain containing chimeric gene construct, consisting of antibiotic resistance and chitinase gene driven by the CaMV 35S promoter, for transformation. Regenerated multiple shoots were selected on a medium containing kanamycin and carbenicillin after exposure to Agrobacterium. The presence and integration of the npt II and chitinase gene were confirmed by polymerase chain reaction(PCR). Northern blot analysis indicated that the genes coding for the enzyme could be expressed in potato plants. The chitinase activity of transgenic potato plants was higher than the control potato.

• Journal of Periodontal and Implant Science
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• v.34 no.4
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• pp.711-722
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• 2004

The purpose of this study is to evaluate the regenerated bone histollogically using titanium reinforced ePTFE(TR-ePTFE) membrane and to investigate cell occlusiveness, wound stabilization and tissue integration of TR-ePTFE membrane. Adult male rabbits (mean BW 2kg) and TR9W (W.L.Gore&Associate.INC,USA) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. TR-ePTFE membrane was applied to defect. Then guided bone regeneration was carried out using TR-ePTFE membrane and resorbable suture. At 2,4,8,12 weeks after the surgery, animals were sacrificed. Nondecalcified specimens were processed for histologic analysis. The result and conclusion of this study were as follows: 1. TR-ePTFE membrane had good ability of biocompatibility and cell occlusiveness. 2. space making for guided bone regenerayion was good at TR-ePTFE membrane. 3. Tissue integration was not good at TR-ePTFE membrane. So, wound stabilization was not good. 4. At 8 weeks, 12 weeks after GBR procedure, bone formation was seen. From the above results, TR-ePTFE membrane fixed tightiy on alveolar bone might be recommended for the early bone formation.

• The Journal of the Korean dental association
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• v.40 no.8 s.399
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• pp.620-627
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• 2002

Oral health depends on the intergrity of the oral mucosa for prevention of the penetration of microbes and macromolecules that might be infectious, allergenic or antigenic. The intraoral immune systems include the tonsils, adenoids and nasopharyngeal-associated lymphoreticular tissue, or NALT. Mucosal inductive sites of the gastrointestinal tract(Peyer's patches and the appendix) and solitary lymph nodes collectively compose the gut-associated lymphoreticualr tissue, or GALT system. Both NALT and GALT are inductive regions where foreign antigens derived from viruses, bacteria, yeast and other molecules are encountered. The integration of tissues in NALT and GALT as part of the mucosal immune system, is very important to keep the oral immune system.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.241-246
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• 2024

The study was carried out by numerical integration based on the diffraction properties and elemental composition. The elemental compositions of breast tissues in the literature were tested. The photon attenuation coefficients calculated using the recent elemental composition were found within 0.2-16% for adipose tissue and within 0.04-17% for glandular tissue with the experimental reference data. The attenuation coefficients of cancerous breast tissue calculated according to the elemental content previously measured in breast cancer patients were found within 0-17% with experimental data in the literature. The attenuation coefficients are of great interest to medical research. To calculate realistic attenuation coefficients, the characteristic coherent scatter, which is most intense at small angles, must be considered. For this reason, experimentally measured form factor data were reviewed, and the most compatible one with the theoretical form factor data produced in this study was used at low momentum transfer x (0 < x ≤ 8 nm^-1). The differential linear coherent scattering distributions were calculated for an energy value of 17.44 keV and compared with their experimental counterparts.