Biomedical subjects

Ryuzo Kawamura

Publications and source records attributed to Ryuzo Kawamura.

2 recordsLinked to original sources

PubMed2006

Doxorubicin encapsulation and diffusional release from stable, polymeric, hydrogel nanoparticles.

We have recently described the preparation of stable, polymeric nanoparticles, composed of poly(ethylene glycol) and poloxamer 407 (Pluronic F127), prepared via inverse emulsion photopolymerization. In the present study we report on the performance of this novel colloidal system as a controlled delivery system for small hydrophobic drugs. Successful encapsulation of doxorubicin occurred through hydrophobic interactions, taking advantage of particle nanoarchitecture. Loadings of up to 8.7wt.% were achieved with a reproducible, fast, solvent evaporation procedure. In vitro drug release, monitored by fluorescence spectrometry and HPLC, revealed a minor burst (approximately 10% at 37 degrees C) and sustained, diffusional release for over 1 week; furthermore, drug encapsulation significantly delayed doxorubicin degradation kinetics.

Diffusion↗

PubMed2006

Transduction of NeuroD2 protein induced neural cell differentiation.

NeuroD2, one of the neurospecific basic helix-loop-helix transcription factors, has the ability to induce neural differentiation in undifferentiated cells. In this paper, we show that transduction of NeuroD2 protein induced mouse neuroblastoma cell line N1E-115 into neural differentiation. NeuroD2 has two basic-rich domains, one is nuclear localization signal (NLS) and the other is basic region of basic helix-loop-helix (basic). We constructed some mutants of NeuroD2, ND2(Delta100-115) (lack of NLS), ND2(Delta123-134) (lack of basic) and ND2(Delta100-134) (lack of both NLS and basic) for transduction experiments. Using these proteins, we have shown that NLS region of NeuroD2 plays a role of protein transduction. Continuous addition of NeuroD2 protein resulted in N1E-115 cells adopting neural morphology after 4 days and Tau mRNA expression was increased. These results suggest that neural differentiation can be induced by direct addition of NeuroD2 protein.

Animals↗