Current Status of Photodynamic Therapy in Digestive Tract Carcinoma in Japan

Photodynamic therapy (PDT) is an effective local treatment modality as a cancer-specific laser ablation in malignancy of some organs including digestive tracts or bile duct. In Japan, PDT has been applied at the early period after the first clinical induction in 1980’s. Although the useful efficacy was clarified, PDT has not been fully applied because of the phototoxicity of the porfimer sodium. The next generated talaporfin-sodium was used for PDT, in which phototoxicity was reduced and, however, the clinical efficacy for digestive tract malignancy has not yet been clarified. By proceeding the experimental and clinical trials, it is necessary to clarify the evidence of efficacy as a local powerful treatment with the conventional surgery, brachiotherapy and chemotherapy in the future step.     

Novel preparation method of highly active Co/SiO2 catalyst for Fischer-Tropsch synthesis with chelating agents

Co/SiO₂ catalysts were prepared by the incipient wetness method using the aqueous Co nitrate solution modified with various organic acids and/or chelating agents followed by drying and calcination. After H₂ reduction at 773 K, the catalyst prepared with nitrilotriacetic acid (NTA) showed Fischer-Tropsch synthesis (FTS) activity ca. 3 times higher than the catalyst without additives under mild reaction conditions (503 K, 1.1 MPa).     

Optical properties and microstructures of Pd-free Ag–Au–Pt–Cu dental alloys

Nine experimental Pd-free Ag–Au–Pt–Cu dental alloys containing 10 at.% Pt and 10–35 at.% Au were prepared and their optical properties and microstructures were investigated by means of spectrophotometric colorimetry, optical microscopy, and electron probe microanalysis. All the alloys were annealed at 850 °C and mirror-polished to observe their reflectance curves in the visible spectrum and three-dimensional color coordinates. All the alloys were composed of a major phase of Ag–Au-rich matrix and a minor and almost colorless Pt–Cu-rich phase. It was found that the color of the alloys was substantially controlled by the Ag–Au-rich matrix and that with increasing Au/Ag atomic ratio from 0.130 to 0.996, the yellow-blue chromaticity index b ^* increased from 8.0 to 14.4, giving a pale yellow color. This systematic increase in yellowness was caused by a continuous shift of the absorption edge of reflectance curve toward longer wavelengths with increasing Au/Ag atomic ratio.     

Zonotopes and the LP-Newton method

Although linear programming problems can be solved in polynomial time by the ellipsoid method and interior-point algorithms, there still remains a long-standing open problem of devising a strongly polynomial algorithm for linear programming (or of disproving the existence of such an algorithm). The present work is motivated by an attempt toward solving this problem. Linear programming problems can be formulated in terms of a zonotope, a kind of greedy polyhedron, on which linear optimization is made easily. We propose a method, called the LP-Newton method, for linear programming that is based on the zonotope formulation and the minimum-norm-point algorithm of Philip Wolfe. The LP-Newton method is a finite algorithm even for real-number input data with exact arithmetic computations. We show some preliminary computational results to examine the behavior of the LP-Newton method. Major part of this paper was presented as a plenary talk with the same title at ICOTA7 (December 12–15, 2007, Kobe, Japan) by the first author. The fourth author’s research was carried out while visiting RIMS in August 2007.     

Effects of urea–formaldehyde resin mole ratio on the properties of particleboard

The use of urea–formaldehyde (UF) resins with lower contents of free formaldehyde in the board industry has led to products with very low emissions of formaldehyde. This study gives a detailed account of the influence on the mechanical and physical properties of the particleboard using UF resins with different mole ratios of formaldehyde:urea within the range 0.97–1.27. The mole ratio influenced not only the thickness swelling (TS) and water absorption (WA) but also the internal bond strength (IB) and the modulus of rupture (MOR) if the manufacturing process was optimized. The investigation revealed clearly that at mole ratios of formaldehyde giving the emission class El the MOR, IB, TS, and WA of particleboard deteriorated. Compensation for the deterioration could be provided through a higher dosage of resin or through the modification of UF resin. However, both alternatives meant that the product would be more expensive.     

Synthesis of poly(1,3-phenyleneethynylenes) membranes having one-handed helical conformation without any chiral side groups by in-situ desubstitution of d-menthoxy groups

In this study, we synthesized four chiral helical poly(phenyleneethynylenes) having optically active menthoxycarbonyl groups and desubstituted the chiral groups in membrane state. Polycondensations of (+)-menthyl 3,5-diethynylbenzoate with (+)-menthyl 3,5-diiodobenzoate, 1,2-diiodobenzenen, 1,3-diiodobenzene, and 1,4-diiodobenzene using PdCl₂(PPh₃)₂–PPh₃–CuI were afforded helical polymers in good yields (named as PMtMt, o-PMtH, m-PMtH, and p-PMtH, respectively). Among them, PMtMt in a mixture of chloroform/benzene showed the largest Cotton effect in absorption region and gave self-supporting membrane by solvent-casting method. PMtMt membrane also showed a Cotton signal similar to that observed in solution. Desubstitution of PMtMt proceeded quantitatively by immersing the membrane into alkaline solution at room temperature for 3 days. The desubstituted PMtMt membrane showed circular dichroism (CD) signals similar shape to that of the original membrane in the UV region in despite of the polymer having no chiral moieties except for helical conformation. This is the first example of synthesis of chiral helical poly(phenyleneethynylenes) without the coexistence of any other chiral moieties.     

Preparation and characterization of gelatin sponge millispheres from air-in-water-in-oil-type emulsions

A novel method for the preparation of gelatin sponge millispheres (GSMs) for biomaterials such as embolic agents and cell scaffolds was developed using an air-in-water-in-oil-type emulsion. The droplets, consisting of a foamy gelatin suspension in caprylic triglyceride, were gelled and rinsed with isopropanol. Sonication and depressurization were used during the rinsing process to create interconnected pores. GSMs cross-links created over 4 h at 155°C without any agent were insoluble and had short and long diameters of 1.1 ± 0.2 mm and 1.3 ± 0.2 mm, respectively. The residual isopropanol and caprylic triglyceride were <0.05% (w/w) and <1% (w/w) respectively. The level of bacterial endotoxins in the extracts was below 0.025 EU/ml, and no bacterial or fungal growth was found during sterility testing. The GSMs produced using this method were considered to meet the basic requirements of embolic agents.