• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1237-1242
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• 2011

The A detailed 3D finite-element analysis model of a human foot has been developed by converting CT scan images to 3D CAD models in order to analyze the distribution of plantar pressure. The 3D foot model includes all muscles, bones, and skin. On the basis of this model and the pressure distribution results, shoes for diabetes patients, which can make the plantar pressure distribution uniform, may be designed through finite-element contact analysis.

• Journal of Periodontal and Implant Science
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• v.27 no.3
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• pp.515-524
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• 1997

헤민과 메나디온 제한에 의한 Porphyromonas gingivalis(P. gingivalis) W50의 병독력의 변화를 검색하고자, 실험관내 병독력을 NIH 3T3 세포의 세포활성 변화로 관찰하였고, 생체내 병독력은 배양상청액을 ICR mouse 피하조직에 주사한 후의 염증반응을 관찰하였다. 헤민 존재 하에 배양한 P. gingivalis W50 배양상청액에 의한 mouse 3T3 세포의 세포활성은 헤민과 메나디온 없이 배양한 세포의 활성보다 낮았다. 헤민과 메나디온을 첨가하지 않고 배양한 세균의 생체내 병독력은 중등도의 염증세포 침윤과 울혈에 의한 출혈, 미약한 세포간질의 부종과 근육 파괴를 보였다. 메나디온 존재 하에서 배양한 세균은 미약한 염증세포의 침윤, 울혈에 의한 출혈 및 근육의 파괴가 관찰되었다. 헤민 존재하에서 중등도의 울혈에 의한 출혈, 미약한 세포간질의 부종, 염증세포의 침윤 및 근육파괴가 관찰되었다. 헤민과 메나디온 존재 하에서 배양한 세균은 심한 염증세포의 침윤과 중등도의 세포간질의 부종 및 울혈에 의한 출혈을 보였다. 이상의 연구 결과 P. gingivalis W50 배양 상층액의 병독력은 헤민에 의하여 영향을 받는 것으로 생각된다.

• KSBB Journal
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• v.8 no.3
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• pp.237-242
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• 1993

Chitin-based fibers have low mechanical strength and hence cannot be used as surgery fiber due to fast degradation In tissues. A new fiber Chitulose was made by mixing chitin with cellulose, both of which have similar structure. A mixture of dimethylacetamide (DMAc) and 6% lithium chloride (LiCl) was found to be an effective solvent system for dissolvoing chitin and cellulose. The Chitulose fiber made by wet spinning of a mixture of chitin and cellulose resulted in the highest degree of strength and flexibility when the ratio of chitin to cellulose was 1.5; 0.2. The fiber maintained mechanical structure even after autoclaving, indicating thermal stability. A biodegradability test of the Chitulose fiber by imbeding in a rat showed that degradation was initiated in 14 days and completely done in 40 days.

• Journal of the Korean Ceramic Society
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• v.41 no.7
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• pp.560-566
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• 2004

To fabricate the continuously porous alumina bodies by multi-extrusion process, carbon powder and ethylene vinyl acetate were used as a pore forming agent and a binder, respectively. As the change of extrusion pass number, reduction ratio as well as the volume fraction of core and tube, the porous alumina bodies having various kind of pore size and porosity could be obtained. The porous bodies showed continuous pore shape, high specific surface as well as high bending strength, which were compared with those of commercial alumina bodies. In-vitro study was carried out using MG-63 osteoblast cells to investigate of their biocompatibility. As a result, the cells grew well on top and bottom as well as inside surface of pore. From the result of in-vivo study of 3-dimensional porous alumina bodies using rats, it was confirmed that any inflammatory response was not found in the subcutaneous tissue around porous body. Also the porous bodies removed from the rats were fully covered with well-developed fibrous tissues and showed the formation of new capillary blood vessels.

• The Journal of the Korean bone and joint tumor society
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• v.15 no.1
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• pp.59-64
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• 2009

Intravascular papillary endothelial hyperplasia (IPEH, Masson's hemangioma) is a non neoplastic reactive endothelial proliferation most commonly located in the skin or subcutaneous tissues although it has been reported in multiple locations throughout the body. This lesion may arise from malformed or normal vessels primarily, and may develop with hemangioma, pyogenic granuloma, or lymphangioma. This lesion, though benign, is clinically important since it may present as a mass and be confused histologically with angiosarcoma. The authors report a 27 years old patient with a mass in his forearm which results in intravascular papillary endothelial hyperplasia.

• Neonatal Medicine
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• v.18 no.1
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• pp.148-152
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• 2011

Necrotizing fasciitis is a rare, but life-threatening infection. Prompt diagnosis and early aggressive intervention is required for survival. However, there has been frequently occurred in delays of diagnosis and treatment due to its non-specific nature. Therefore, a high index of suspicion is needed to ensure timely intervention. We report a case of necrotizing fasciitis in a 7-day-old term healthy neonate.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.77-87
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• 1982

The purpose of this study is to estimate the reaction of rat subcutaneous tissues following exposure to the various concentrations of formocresol (100, 50, 20%), eugenol (100, 75, 50%), and sodium hypochlorite. (5, 3.5, 0.5%) The results were as follows: 1. As the concentration of formocresol was decreased, the inflammatory reaction was decreased conspicuously. 2. The inflammatory reaction of 100% eugenol was appeared to be similar to that of 75% eugenol. The inflammatory reaction of 50% eugenol was decreased conspicuously. 3. No significant differences were found in inflammatory response between 3.5% and 5% sodium hypochlorite. 4. The inflammatory reaction of 0.5% sodium hypochlorite was mild and appeared to be similar to that of saline solution in 7 days.

• Journal of Chest Surgery
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• v.35 no.2
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• pp.94-101
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• 2002

All kinds of tissue valves must be pretreated for the inactivation of immunologic properties and the strengthening of tissue before implantation. However, the tissue valves are gradually denatured with the calcification process and they eventually lose their functions. Recent reports have shown the existence of specific calcium binding non collagenous proteins in the calcified area of implanted biomaterials. This experiment was intended to confirm the effect of pretreatment with RGDS(Arg-Gly-Asp-Ser) tetrapeptide on the calcification of subcutaneously implanted bovine pericardium in rats. RGDS tetrapeptide has the same amino acid sequence of attachment site of specific calcium binding non collagenous proteins. Material and Method: All bovine pericardial pieces were fixed with 0.6% glutaraldehyde. The pretreatments were done using 5 different methods, groupI, with normal saline for 60 minutes, groupII, with 0.5% GRSD(Gly-Arg-Scr-Asp) tetrapeptide solution for 60 minutes, group III : with 0.5% RGDS(Arg-Gly-Asp-Ser) tctrapeptide for 30 minutes, group IV ; with 0.5% RGDS for 60 minutes, and group V : with 0.5% RGDS for 120 minutes. The pretreated bovine pericardial pieces were implanted subcutaneously at the abdominal sites of rats. 30 days after the implantation, the implanted bovine pericardial tissue were examined radiologically, biochemically, and histologically to measure the severity of calcification. Result: On the radiological examination, group I ; 68.42$\pm$3.06, group II , 64.25$\pm$5.58 showed significant difference with group III: 48.00$\pm$3.57, group IV; 43.67$\pm$2.31, and group V ; 2.58$\pm$2.47(p<0.05). There was no difference between group I and II(p=0.105). On the biochemical examination, the amount of calcium in group I was , 33.09$\pm$6.59 mg, in group II ; 28.12$\pm$5.50mg, in group III ; 25.42$\pm$7.67mg, in group Ⅵ ; 20.51$\pm$5.11mg, and in group V : 15.43$\pm$4.25mg.

• Applied Microscopy
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• v.36 no.4
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• pp.271-277
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• 2006

Mast cells (MCs) are granulated cells that play a pivotal role in allergic reaction and inflammation. The granules of mast cells are known to be rich in zinc (Zn). Male Sprague-Dawley rats were used. We injected $200{\mu}L$ of complete Freund's adjuvant (CFA) subcutaneously in the dorsal aspect of one hindpaw Finally, zinc selenium autometallography(AMG) was done by Danscher's method. The present study showed the ultrastructures of zinc-containing mast cells found in inflammatory area following an complete freund's adjuvant (CFA) inoculation into the rat hindpaw. At light microscopic level, mast cells were round or oval, at average $12{\mu}m$ in diameter, with many filopodia extending from the cell surface. Because the rather small and spherical nucleus was centrally placed; it was frequently obscured by the cytoplasmic granules, it sometimes could not be seen. Mast cells were distributed chiefly in the vicinity of small blood vessels. In most preparation many mast cells were ruptured and their granules escaped into the surrounding tissue. In electron micrographs, The secretory granules were at average $0.5{\mu}m$ in diameter and were limited by a membrane. The cell surface contained numerous microvilli and folds. Their interior was heterogenous in appearance. The nucleus was surrounded by large numbers of prominent vesicels and a well developed Golgi apparatus, but scant endoplasmic reticulum.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.451-455
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• 1998

Bovine pericardial bioprosthesis treated with glutaraldehyde is one of the most popular prosthetic materials, but late calcific degeneration must be solved. According to the alleged hypothesis of this calcification mechanism the free aldehyde groups on the surface of the tissue treated with glutaraldehyde bind to the circulating free calcium and induce mineralization. For mitigating the calcific degeneration, I added MgCl2 into the 0.625% glutaraldehyde solution to compete with calcium for binding to free aldehyde from the glutaraldehyde. I prepared 60 pieces of square shaped bovine pericardia and fixed in the 0.625% glutaraldehyde solution as control group(group 1), and the other 60 pieces in the same glutaraldehyde solution with 4g/L MgCl2 6H2O as the other group(group 2). After fixation for 1 month these were implanted into the bellies of 60 Sprague-Dawley rats subdermally and extracted on 1 month, 2 months, 3 months and 6 months later. With atomic absorption spectophotometry I measured the deposited calcium amount with the following results; 1 month and 2 months after implantation I could not find any differences between two groups, but in the 3rd month calcium was 1.738 mg/g in group 1 and 0.786 mg/g in group 2 and in the 6th month calcium had risen to 3.102 mg/g in group 1 and 1.623 mg/g in group 2, which has statistical significance(p<0.05). This means magnesium shows meaningful calcium mitigation effects on subcutaneously implanted bovine pericardium in the rat models.