Generation of human induced pluripotent stem cells from oral mucosa

Induced pluripotent stem (iPS) cells are one of the most promising sources for cell therapy in regenerative medicine. Using a patient's own genetically identical and histocompatible cells is the ideal way to practice personalized regenerative medicine. For personalized iPS cell therapy, the prerequisites for cell source preparation are a simple and safe procedure, no aesthetic or functional damage, and quick wound healing. Oral mucosa fibroblasts (OFs) may have high potential to fulfill these requirements. In this study, biopsy was performed in a dental chair; no significant incisional damage was recognized and rapid wound healing (within a week) was observed. We generated human iPS cells from the isolated OFs via the retroviral gene transfer of OCT4, SOX2, c-MYC, and KLF4. Reprogrammed cells showed ES-like morphology and expressed undifferentiated markers such as OCT4, NANOG, SSEA4, TRA-1-60, and TRA-1-81. Subsequent in vitro and in vivo analyses confirmed the pluripotency of resultant iPS cells, which matched the criteria for iPS cells. In addition, we found that the endogenous expression levels of c-MYC and KLF4 in OFs were similar to those in dermal fibroblasts. Taken together, we propose that OFs could be a practical source for preparing iPS cells to achieve personalized regenerative medicine in the near future.     

Development of a high activity HDS catalyst for diesel fuel: from basic research to commercial experience

Cosmo Oil and Petroleum Energy Center (PEC) have developed a new hydrodesulfurization (HDS) catalyst of high activity, C-603A, to produce clean diesel fuel, whose sulfur content is less than 0.05 mass%. The preparation of this catalyst combines the use of zeolite technology and impregnation technology to provide excellent HDS activity. C-603A possesses significantly higher activity than conventional Co–Mo/alumina catalyst. Industrial operation with this catalyst has successfully proven its high performance.     

Nano-Size Molecular Conductors on Silicon Substrate Toward Device Integration of Conductive CT Salts

Nano-size crystals of molecular conductors have been directly formed on SiO₂/doped-Si substrates. Two kinds of methods were used for this on-site crystal growth, one of which is electrochemical crystallization on electrodes prepared on the substrate, and the other of which is direct reaction of metal copper or silver electrodes with acceptor molecules such as DCNQI (= N,N′-Dicyanobenzoquinonediimine) derivatives on the substrate. In both cases, we have succeeded in bridging two or more electrodes with the single crystal of the molecular conductors. Temperature dependence of the resistivity often exhibited significantly different behaviors from those of the corresponding bulk crystals. Origins of the unusual behaviors of the nano-crystals are discussed.     

Carbon-coated graphite for anode of lithium ion rechargeable batteries: Carbon coating conditions and precursors

Carbon coating of natural graphite particles was performed by mechanical mixing of natural graphite with different carbon precursors in a scale of about 100 g. Anode performance in lithium ion rechargeable batteries was studied on the resultant carbon-coated graphite. Carbon formed on graphite particles had amorphous structure and low density. By carbon coating, a decrease in irreversible capacity of the first charge/discharge cycle in an electrolyte solution of EC/PC = 3/1 was observed, without noticeable change in discharge capacity. Carbon derived from different precursors did not give any marked difference in anode performance of carbon-coated graphite. Optimum conditions for carbon coating were determined as the coating of 4-13 mass% at 700-1000 °C. The present mechanical mixing of natural graphite and carbon precursor in powder is concluded to be a simple but sufficient process to produce carbon-coated graphite for anode material in lithium ion rechargeable batteries. As carbon precursor, PVA was shown to be one of the appreciable carbon precursors.     

Hexagonal boron nitride as a new ultraviolet luminescent material and its application—Fluorescence properties of hBN single-crystal powder

Luminous properties of hexagonal boron nitride (hBN) single-crystal powder were studied by cathodoluminescence and photoluminescence spectroscopy. The single crystals grown by a high pressure and high temperature method showed typical excitonic spectra at peak wavelengths of 215, 220, and 227 nm at room temperature. Well-faceted hexagonal shaped single crystals exhibited the dominant 215-nm band. The 220- and 227-nm bands were singly or concurrently observed in the case of irregular-shaped crystal powders, though no discernible difference between the morphologies of crystal powders showing differently superimposed luminous spectral profiles of the 220- and 227-nm bands was observed. However, each band showed different spectral and decay features at 8 K, implying that the origins of the two bands are different.     

High-performance liquid chromatographic separation of enantiomeric benzyl glycerides

The enantiomeric resolution of a series of 1,2-diacyl- and 1,2-mixed acid-diacyl-3-benzyl-rac-glycerols was investigated by high-performance liquid chromatography (HPLC). Of the racemic benzylglycerols studied, the 1-O-benzyl-2,3-O-iso-propylidene-rac-glycerol 1-acyl-3-benzyl-rac-glycerol and 2-acyl-3-benzyl-rac-glycerol structures could be resolved into their enantiomers. The latter were resolved on a silica (10 μm) column coated with cellulose tribenzoate by isocratic elution with hexane/isopropanol mixtures as mobile phase. The effects of para substitution of the benzyl moiety on the resolution of the acylbenzylglycerols by this HPLC method were evaluated. Presented in part at the AOCS 81st Annual Meeting, Baltimore, Maryland, April 1990. Reference to a brand or firm name does not constitute endorsement by the U.S. Department of Agriculture over others of a similar nature not mentioned.