• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.555-564
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• 2001

The purpose of this study is to evaluate the bioresorbability of Calcium Polyphosphate added with $Na_2O$ and chitosan. Though calcium phosphate ceramics meet some of the needs for bone replacement, they have some limitation of unresorbability and fibrous encapsulation without direct bone apposition during bone remodelling. To solve these problem, we developed a new ceramic, calcium polyphosphate(CPP), and report the biologic response to CPP in extraction sites of beagle dog. Porous CPP granules were prepared by condensation of anhydrous $Ca(H_2PO_4)_2$ to form non-crystalline $Ca(PO_3)_2$. CPP granules added with $Na_2O$ and chitosan were implanted in extraction sockets and histologic observation were performed at 12 weeks later. Histologic observation at 12 weeks revealed that CPP matrix were mingled with and directly apposed to new bone without any intervention of fibrous connective tissue. CPP granules added with chitosan were well adatped without any adverse tissue reaction and resorbed slowly and spontaneously. CPP granules added with $Na_2O$ and chitosan show multinucleated giant cells and osteoblast-like cells around grafted material and newly formed bone. This result revealed that CPP, regardless of its additive component, had a high affinity for bone and had been resorbed slowly. From this results, it was suggested that CPP is promising ceramic as a bone substitute and addition of $Na_2O$ and chitosan help biodegradation. In further study , it will be determined which concentration of $Na_2O$ help biodegradation and the other additive components increase the degradation rate.

• The Journal of the Korean bone and joint tumor society
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• v.19 no.2
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• pp.56-63
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• 2013

Purpose: This study was performed to evaluate the efficiency of demineralized bone matrix (DBM, Genesis$^{(R)}$) used for bone defect after operative traetment of benign bone tumors by clinical and radiological methods. Materials and Methods: DBM was used to treat bone defect after operative treatment of benign tumor from February 2012 to May 2013. Total 25 benign bone tumor cases (15 males, and 10 females) with mean age of 30.3 were studied. The diagnoses were solitary bone cyst in 9 cases, non ossifying fibroma in 5, fibrous dysplasia in 5, aneurysmal bone cyst in 3 and enchondroma in 3. In categorization by location of tumor, there were 5 cases of distal femur, 4 of proximal tibia, 3 of proximal femur, 3 of proximal humerus, 3 of phalanx, 2 of distal radius, 2 of hip bone, 2 of calcaneus, and 1 of scapula. Autogenous bone was used with DBM in 6 cases, and only DBM used in 19 cases. Mean periods of follow up were 8.7 months (range: 6 to 14 months). Amount of graft resorption and bone formation was observed with compare of post operation radiograph and the difference was shown by percentage. Resorption level was measured by DBM level which could be observed from simple x-ray, and bone formation level by bone trabecular formation level at impaired site. Results: Twenty three cases of total 25 cases showed bone union. In the 23 cases, more than 98% DBM resorption was observed after mean 4.3 months, and more than 98% bone formation was observed after mean 6.9 months. Lesser bone defect sizes showed faster bone formation and it was statistically significant (p=0.036). But other comparative studies on other factors such as, sex, age of patients and combination of autogenous bone were no statistically significant differences in graft resorption and bone formation. And there was no significant complication in periods of follow-up. Conclusion: Demineralized Bone Matrix (Genesis$^{(R)}$) is thought to be useful treatment for bone defect after operative treatment of benign bone tumor, however longer follow-up periods appears to be needed.

• Development and Reproduction
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• v.4 no.1
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• pp.67-77
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• 2000

Snailfish usually lives at the bottom of the sea and showed typical retrogressive change with specialized tissue structures of skin and skeletons. In order to obtain the specific genes of snailfish, highly expressed in the body, we made subtracted cDNA library and analyzed 200 clones. Totally 200 clones were obtained and sequenced, and among them 62 clones were turned out to be homologous to the known gene, i.e., thioesterase (9), myosin (8), creatine kinase (7), skeletal alpha-actin (6), parvalbumin b (5), ribosomal protein (5), type I collagen (3), muscle troponin (3), dopamine receptor (2), histatin (2), and heat shock protein (2), cystatin (1), lectin (1), statherin (1), secretory carrier membrane protein (1), keratin type I (1), desmin (1), chloroplast (1), muscle tropomyosin (1), reticulum calcium ATPase (1), ribonucleoprotein (1). The remaining 138 clones were low homologous or non-redundant genes through Genbank search. Especially 5 clones were novel and specifically expressed in the body tissues of Snailfish by in situ hybridization. Therefore, we analysed these 5 clones to identify the C-terminal protein structures and motifs, and partly defined the roles of these proteins in comparison with the expression patterns by in situ hybridization. C9O-77, about 5000 bp, was supposed to be a matrix protein expressed strongly positive in epithelium, myxoid tissue, fibrous tissue and collagenous tissue. C9O-116, about 1500 bp, was supposed to be a transmembrane protein which was weakly expressed in the fibrous tissue, epithelium tissue, and myxoid tissue, but strong in muscle tissue. C9O-130, about 1200 bp, was supposed to be an intracytoplasmic molecule usually in the epithelial cells. C9O-161, about 2000 bp, was weakly expressed in epithelium, muscle tissue and myxoid tissue, but specially strong in epithelium. C9O-171, about 1000 bp, was supposed to be a transcription factor containing zinc finger like domain, which was intensely expressed in the epithelium, muscle tissue, fibrous tissue, and in collagenous tissue.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.3
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• pp.34-41
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• 1990

The pilomatricoma (calcifying epithelioma of Malherbe) is rare benign hard, spherical and freely movable cutaneous tumor, which was differentiated from hair cells, particulary hair cortex cells. It is usually occured as a single, asymptomatic, 0.5 cm to 3.0 cm sized, deep seated, firm nodule, covered by normal or pink skin. It arises chiefly in young people, including children, and most often in the head, neck and upper extrimites. The authers experienced a case of pilomatricoma which occured in preauricular region. This case was summarized as follows. 1. 10 years old female has suffered from hard subepidermal mass on preauricular area and she visited our out patient clinic. So we performed surgical extirpation and the excised specimen was pathologically examined. 2. Grossly the tumor measures 2.0 cm in diameter and firm, bosselated, spherical shaped which covered by a thin layer of fibrous tissue. On cut section, it shows spicular gritty surfaces, well encapsulation, interwoven and keratotic lamellae. 3. Histopathologically, the epithelial masses of the tumor are composed of two type of cells, basophilic cells and shodow cells. The basophilic cells resemble hair matrix cells which posses round or elogated, deeply basophilic nuclei and scanty cytoplasm. The shadow cells show a central, unstained shadow at the site of the lost nucleus. Gradual development of basophilic cells into shadow cells can be observed. Foci of calcification are present within the lobule of shadow cells. The stroma of the tumor shows a considerable foreign body giant cell reaction adjacent to the shadow cells. 4. No recurrence was observed until post-operative 40 months.

• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.559-568
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• 1998

direct bone apposition during bone remodelling. To address these problem, we developed a new ceramic, calcium metaphosphate(CMP), and report herein the biologic response to CMP in subcutaneous tissue, muscle and bone. Porous CMP blocks were prepared by condensation of anhydrous $Ca(H_2PO_4)_2$ to form non-crystalline $Ca(PO_3)_2$. Macroporous scaffolds were made using a polyurethane sponge method. CMP block possesses a macroporous structure with approximate pore size range of 0.3-1mm. CMP blocks were implanted in 8mm sized calvarial defect, subcutaneous tissue and muscle of 6 Newzealand White rabbits and histologic observation were performed at 4 and 6 weeks later. CMP blocks in subcutaneous tissue and muscle were well adapted without any adverse tissue reaction and resorbed slowly and spontaneously. Histologic observation of calvarial defect at 4 and 6 weeks revealed that CMP matrix were mingled with and directly apposed to new bone without any intervention of fibrous connective tissue. CMP blocks didn't show any adverse tissue reaction and resorbed spontaneously also in calvarial defect. This result revealed that CMP had a high affinity for bone and was very biocompatible. From this preliminary result, it was suggested that CMP was a promising ceramic as a bone substitute and tissue engineering scaffold for bone formation.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.623-634
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• 1995

Periodontitis is characterized by gingival inflammation and results in periodontal pocket formation with loss of the supporting alveolar bone and connective tissue around the teeth. Therapeutic modalities should therefore aim not only at eliminating the gingival inflammatory process and preventing the progression of periodontal disease but also at reestablishing and regenerating the periodontal tissue previously lost to the disease. To achieve periodontal regeneration, progenitor cells must migrate to the denuded root surface, attach to it, proliferate and mature into an organized and functional fibrous attachment apparatus. Likewise, progenitor bone cells must also migrate, proliferate, and mature in conjunction with the regenerating periodontal ligament. Significant advances have been made during the last decade in understanding the factors controlling the migration, attachment and proliferation of cells. A group of naturally occuring molecules known as polypeptide growth factors in conjunction with certain matrix proteins are key regulators of these biological events. Of these, the fibroblast growth factor(FGF), platelet-derived growth factor(PDGF) , insulin like growth factor(CIGFs), transforming growth factor(TGFs), epidermal growth factor(EGF) and bone morphogenetic growth factor(BMPs) apper to have an important role in periodontal wound healing. The purpose of this study was to determine the effects of BMP on periodontal ligament cells. Human periodontal ligament cells were cultured from extracted tooth for non-periodontal reason. Cultured periodontal ligament cells were treated with BMP. Cellular activities were determined by MTT(3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay and ALP(alkaline phosphatase) activity. The results were as follows ; Regardless of cultured time, cellular activities were stimulated by BMP. Also, BMP greatly increased alkaline phosphatase(ALP) in periodontal ligament cells. These results suggest that BMP not only have no cytotoxic effect on periodontal ligament cells, but also have osteogenic stimulatory effect on periodontal ligament cells.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.109-112
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• 2011

Purpose: Neurofibromas may present as multiple or solitary lesions. Although there is no predilection site for solitary lesions, they are rare on the hand. In addition, solitary intramuscular neurofibromas are a very rare pathological type. Here, we report a rare solitary intramuscular neurofibroma in the hand. This paper examines the clinical characteristics of intramuscular neurofibroma arising from the lumbricalis in order to enable a correct diagnosis and treatment. Methods: A 32-year-old male presented with a painless mass on the palm. The physical examination revealed a $3{\times}2$ cm protruding mass that was non-tender to palpation. The vascular and sensory examinations were unremarkable, while the motor examination showed mild difficulty with flexion and extension. Magnetic resonance imaging demonstrated an enhancing solid mass between the thenar eminence and second metacarpophalangeal joint. The diagnosis of an intramuscular neurofibroma was confirmed following surgical excision and histological evaluation. Results: The pathological examination was consistent with a neurofibroma, with delicate fascicles and loose fusiform cells in a fibrous stroma, with oval or spindle-shaped nuclei and scant cytoplasm. The background matrix was pale staining and had focal myxoid stroma. There was no significant nuclear pleomorphism and no mitoses. Immunohistochemistry with S-100 was slightly positive. At the 6-month follow-up, motor and sensory function were intact and the range of motion was full. Conclusion: A neurofibroma is a rare tumor of the hand, especially the intramuscular type. Hand surgeons should consider the diagnosis of this tumor based on the examination and imaging.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.495-498
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• 2009

Brown tumor is the benign bone lesion consists of woven bone and fibrous tissue without matrix, which develop due to chronic excessive osteoclastic activity such as hyperparathyroidism. Usually they appear with normal uptake or occasionally focally increased uptake on bone scan. We present a case with brown tumor shown more increased uptake and more number of lesions on bone scan after parathyroidectomy, and lesser increased uptake on serial bone scans without any other treatment through several months. This finding is thought to be similar to 'flare phenomenon' which is occasionally seen after treatment of metastatic bone lesions of malignant cancer, and may represent curative process of brown tumor with rapid normal bone formation.

• Journal of the Korean institute of surface engineering
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• v.49 no.6
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• pp.555-559
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• 2016

A biodegradable nanofiber scaffolds using electrospining provide fibrous guidance cues for controlling cell fate that mimic the native extracellular matrix (ECM). It can create a pattern using conventional electrospining method, but has a difficulty to generate one or more pattern structures. Femtosecond(fs) laser ablation has much interested in patterning on biomaterials in order to distinguish the fundamental or systemic interaction between cell and material surface. The ablated materials with a short pulse duration using femtosecond laser that allows for precise removal of materials without transition of the inherent material properties. In this study, linear grooves and circular craters were fabricated on electrospun nanofiber scaffolds (poly-L-lactide(PLLA)) by femtosecond laser patterning processes. As parametric studies, pulse energy and beam spot size were varied to determine the effects of the laser pulse on groove size. We confirmed controlling pulse energy to $5{\mu}J-20{\mu}J$ and variation of lens maginfication of 2X, 5X, 10X, 20X created grooves of width to approximately $5{\mu}m-50{\mu}m$. Our results demonstrate that femtosecond laser processing is an effective means for flexibly structuring the surface of electrospun PLLA nanofibers.

• Composites Research
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• v.12 no.2
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• pp.10-25
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• 1999

A new evaluation method for the interfacial properties of fibrous composites based on a fragmentation technique is proposed by using the gradual multi-fiber composite, in which the inter-fiber spacing is gradually changed. The results showed that as the inter-fiber distance increased, the aspect ratio of broken fibers decreased while the interfacial shear strength between the fiber and matrix increased. When the reciprocal of the inter-fiber destance was taken for the above relations, both the aspect ratio and interfacial shear strength showed a saturated value. This means that the gradual multi-fiber composite indicates an upper bound in aspect ratio and an upper bound in interfacial shear strength. It was concluded that this fragmentation test could be a new method for composite evaluation, since reducing a difference between these two bounds is effective for composite strengthening. In addition an elastoplastic finite element analysis was carried out to relate the above results with fiber stress a distribution around fiber breaks. It was proved that the bound obtained in the gradual multi-fiber composite test is closely related to stress concentrations caused by a group of multi-fiber breaks.