神澤 信行

強力なキレート作用を持つノシトールリン酸 (IP6) は多くの動植物の細胞内に存在し、細胞増殖、分化など極めて重要な細胞機能を制御する役割を担っている。特に抗腫瘍効果を有し、安全性が高いことからガン治療への応用が期待されている。我々はこれまでにIP6 を水酸アパタイト(HAp)の粒子表面に修飾し、IP6 のキレート能で硬化する「キレート硬化型アパタイトセメント(IP6-HAp セメント)」の開発に成功している [1]。本研究では、まず始めにヒト骨肉腫細胞 (HOS) におけるIP6 単独の抗腫瘍効果を解析し、ついでIP6-HAp セメント上でHOS 細胞を培養し、その細胞の接着性や増殖性、形態を観察した。

<p>The expression levels of osteoblast differentiation markers and the effect of geometry of porous hydroxyapatite (HAp) fiber scaffold on the differentiation were investigated. The glyceraldehyde-3-phosphate dehydrogenases (GAPDH) mRNA was used as internal control to estimate expression level of differential marker mRNA. An apparent acceleration of the expression was observed for osteoblast differentiation in induced condition. The results show that the materials with various pore sizes effects the three-dimensional apatite fiber scaffold on cell profileration and differentiation.</p>

<p>The effectiveness of hydroxyapatite fibers (HAF) as a scaffold of osteoblastic cells for bone generation was investigated. Three types of HAF with different diameters of pores and porosity were used in the study. The results showed that HAF is degradable and can be eventually replaced by bone tissue in vivo. The results suggested that HAF can be used as an effective scaffold for osteoblast-like cells having capability for bone conduction and that HAF with larger pore sizes can be replaced by newly formed bone tissue in vivo.</p>

The sensitive plant, Mimosa pudica L. closes the leaves and hangs the petiole down when stimulated by touch or heat treatment. This bending of the petiole is caused by rapid shrinking of the lower side of motor organs called the pulvinus. MRI technique indicates that the water in the main pulvinus transfers from the flexor to the extensor during the rapid bending. The actin cytoskeleton in the motor cells plays in important role in the petiole bending. The actin molecules in Mimosa pudica L. is heavily tyrosine-phosphorylated. The bending of Mimosa pudica L. is correlated with reduced actin phosphorylation in the pulvinus.