Jung Eun Kim

Proteomic analysis of the biological response of MG63 osteoblast-like cells to titanium implants

Understanding of the interaction between human MG63 osteoblast-like cells and surfaces is necessary in the field of tissue engineering and biomaterials. Various titanium surfaces are widely used as not only implant materials, but also as miniscrews in orthodontics. Our goal was to assess the proteomic response of MG63 osteoblast-like cells to different titanium surfaces. MG63 osteoblast-like cells were cultured on three different titanium surfaces: a smooth surface (S), a sandblasted with large grit and acid-etched surface (SLA), and a surface coated with a thin layer of hydroxyapatite (HA). Cells grown on the rougher surfaces (SLA and HA) exhibited downregulated cell proliferation and morphological changes. In the proteomic analysis, cells grown on the SLA surface showed upregulated expression of protocadherin-β3 precursor, kinase insert domain receptor, fibroblast growth factor receptor-3, and insulin-like growth factor I, while the expression levels of cell adhesion kinase, collagen α-1(I) chain precursor, collagen type XI α2, and cadherin-11 were upregulated in cells grown on the HA surface. These proteins are known to be involved in osteoblast adhesion, growth, and differentiation. Thus, the surface properties of dental materials can influence the expression of proteins involved in osseointegration-related processes. Proteomic analysis may reveal changes in novel proteins that explain why osseointegration varies depending on surface properties.

Non-interactive Cryptosystem for Entity Authentication

In case of mobile agent based computing system such as agent-based electronic payment and online electronic publishing of multimedia contents, both precise identification and secure authentication schemes are required for its security. The public-key cryptosystem and the digital signature scheme have been the foundation of overall secure systems. The requirement for providing agent based secure digital contents in electronic commerce is to implement the compatible secure entity authentication scheme. In this paper, existing discrete logarithm based Schnorr like authentication schemes are improved by the analysis of performance and security on the interactive protocols. And ElGamal type authentication schemes are also proposed. Then, they are enhanced with oblivious transfer based non-interactive public key cryptosystem for entity authentication. Proposed non-interactive protocols are applicable to the noninteractive zero knowledge proofs and they can provide compatible performance and safety in distributed commerce applications such as copyright protection system on multimedia contents.