• Journal of Life Science
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• v.6 no.4
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• pp.286-292
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• 1996

Angiogenesis is a fundamental process by which new blood vessels are formed. It is essential in embryo development, and wound healing. Furthermore, malignant tumor growth and metastasis are also angiogenesis-dependent. In the catilage tissue, normal angiogenesis process is suppressed. In fact, it was reported that angiogenesis-inhibitory substances were isolated from the extracts of cow and shark catilage tissue. In order to isolate genes involved in the regulation of angiogenesis from a catilage fish, we constructed a shark cDNA library from Scylliohinus torazame. We then screened the library using hyman tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) gene as a probe. Among the 4 X 10$^{4}$ plaques screened, we isolated 2 positive clones (T-1, T-2). Restriction enzyme analysis revealed that the T-1 clone contains 0.8 kb cDNA insert, and the T-2 clone contains 1.2 kb and 2.2 kb inserts, respectively. Further DNA sequence analysis shows that the DNA sequence of the T-1 clone is 53% homologous to that of the human TIMP-1 gene.

• Tribology and Lubricants
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• v.13 no.1
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• pp.82-87
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• 1997

The modern orthopaedics frequently uses the total hip replacement in the artificial hip joint. The wear in this joint requires a re-replacement of hip joints because it is under the severe load and friction conditions. To solve these problems the previous studies have been mainly focussed on the development of new materials. The research of new materials, however, needs much time and effort since it should be experimented for its bio-compatibility, friction, and wear characteristics. To reduce the work, in this study, the finite element analysis is applied to find new combinations of bio-materials in the total hip replacement which has the excellent contact characteristics. A non-linear FEM program MARC with 5-node axisymmetric element was used for analyzing the contact stresses between the hip joints. The computed results show that in case of acetabulum UHMWP has good characteristics, in femoral head, $Al_2O_3$, and in stem, Ti6Al4V.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1996.10a
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• pp.189-194
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• 1996

The modern orthopaedics frequently uses the total hip replacement in the artificial hip joint. The wear in this joint requires the re-replacement of the hip joint beacuse it is under the severe load and friction conditions. To solve these problems the previous studies have been mainly focused on the development of the new materials. The research of new material, however, needs much time and effort since it should be experimented for its bio-compatibility, friction, and wear characteristics. To reduce the work, in this study, the finite element analysis is applied to find the new combination of the materials in the total hip replacement which has the excellent contact characteristics. The finite element uses MARC and the 5-node aximetric element. The results show that in case of acetabulum UHMWP has good characteristics, in femoral head, the $Al_2O_3$, and in stem, Ti6Al4V.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.1-4
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• 2005

Previous sucessful results of neocartilage formation using tissue engineering technique in immunocompromised nude mouse xenograft model were reported. For clinical application, autogenous cell is preferrable to allogenic or xenogenic cell for circumvention of immune rejection. This study evaluates the feasibility of producing a engineered cartilage using autogenous chondrocytes. Chondrocytes were isolated from the auricular catilage of New Zealand White rabbit and seeded onto PGA polymer coated with polylactic acid in round pattern(diameter 0.7 cm, thickness 0.1 cm) at a concentration $7{\times}10^7$ chondrocytes per $cm^3$. Each Autogenous Cell-polymer constructs were implanted subcutaneously into the left side of dorsum of twelve Rabbits. Polymer templates not containg cells were implanted into the right side as a control. Fifteen rabbits were sacrificed at the following intervals: 5 rabbits at nine weeks, 7 rabbits at twelve weeksNew autogenous cartilage formation which retained the approximate dimensions of origianl round polymer template in 11 of 12 cell seeded implants. Histological examination using hematoxyline and eosin stain revealed vast majority of implants developed into mature cartilage. This study opens up the possibility of autologus cell transplant to construct autogenous cartilge.

• Polymer(Korea)
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• v.38 no.3
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• pp.278-285
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• 2014

Demineralized bone particles (DBP) and alginate hybrid sponges were fabricated at 10, 20, 40 and 80% DBP/alginate hybrid ratios for seeding chondrocyte. Cell proliferation was measured via MTT assay. Morphological observation, histology, biological assay and RT-PCR were performed at each time point 1, 2 and 3 weeks. The cell viability was better in 20% DBP/alginate sponges than in other sponges. SEM results showed that more attached and more proliferated cells in the 20% DBP/alginate sponges with the lapse of time. Finally, histochemical assay results showed that the phenotype of chondrocyte was well maintained and both acidic mucopolysaccharide and type II collagen was well formed at 20% sponges. This study suggested that DBP/alginate sponge may serve as a potential cell delivery vehicle and a structural basis for tissue engineered articular cartilage.