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Highlights • It is difficult to irradiate individual mouse lymph nodes (LNs) 1–2 mm in diameter. • A maximum single dose is, Utilizing mice with swollen lymph nodes, we succeeded in irradiating individual metastatic lymph nodes through a hole in a lead shield. This system enabled us to increase the radiation dose to >8 Gy (the lethal dose for total-body irradiation) and evaluate both direct and abscopal antitumor effects.

A perfusion defect in metastatic lymph nodes (LNs) can be visualized as a localized area of low contrast on contrast-enhanced CT, MRI or ultrasound images. Hypotheses for perfusion defect include abnormal hemodynamics in neovascular vessels and decrease in blood flow in pre-existing blood vessels in the parenchyma due to compression of tumor growth in the LNs. However, the mechanism of perfusion defects in LNs during the early stage of LN metastasis has not yet been investigated. Here we show that the formation of a tumor mass with very few microvessels was associated with the development of a perfusion defect in the non-enlarged LN at the early stage of LN metastasis. We found in a mouse model of LN metastasis induced using non-keratinizing tumor cells that during formation of the perfusion defect in non-enlarged LN, the number of blood vessels £ 50 mm in diameter decreased, while the volume of existing blood vessels >50 mm in diameter increased using contrast-enhanced high-frequency ultrasound and contrast-enhanced micro-CT imaging systems with a maximum spatial resolution of > 30 mm. Furthermore, we found that tumor angiogenesis and pO2 changes in the metastatic LN were not observed. Our results demonstrate that the perfusion defect appear to be a specific form of tumorigenesis in the LN as vascular-rich organ at the early stage of metastasis. We anticipate a perfusion defect on ultrasound, CT or MRI images to be used as an indicator in the non-enlarged LN at the early stage of LN metastasis.

Interface manipulation to pursue unusual nanostructures was performed using a strategically designed triblock terpolymer with a short middle segment, poly(styrene-b-methyl methacrylate-b-2,2,2-trifluoroethyl methacrylate). A short middle segment of poly(methyl methacrylate) (PMMA) that does not form any distinct domains was found to play an important role in manipulating the interface between the polystyrene (PS) and poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) domains and forming unconventional partially continuous oblate cylinders with an oblique lattice, as confirmed by small angle X-ray scattering (SAXS) and dual-axis transmission electron microtomography (TEMT). Interface manipulation to pursue unusual nanostructures was performed using a strategically designed triblock terpolymer with a short middle segment, poly(styrene-b-methyl methacrylate-b-2,2,2-trifluoroethyl methacrylate). A short middle segment of poly(methyl methacrylate) (PMMA) that does not form any distinct domains was found to play an important role in manipulating the interface between the polystyrene (PS) and poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) domains and forming unconventional partially continuous oblate cylinders with an oblique lattice, as confirmed by small angle X-ray scattering (SAXS) and dual-axis transmission electron microtomography (TEMT).

Hypoxia appears to have an important role in pathological conditions in many organs such as kidney; however, a method to quantify intracellular oxygen tension in vivo has not been well established. In this study, we established an optical method to quantify oxygen tension in mice kidneys using a cationic lipophilic phosphorescence probe, BTPDM1, which has an intracellular oxygen concentration-sensitive phosphorescence lifetime. Since this probe is distributed inside the tubular cells of the mice kidney, we succeeded in detecting acute renal hypoxic conditions and chronic kidney disease. This technique enabled us to estimate intracellular partial pressures of oxygen in vivo by extrapolating the calibration curve generated from cultured tubular cells. Since intracellular oxygen tension is directly related to cellular hypoxic reactions, such as the activation of hypoxia-inducible factors, our method will shed new light on hypoxia research in vivo.

A novel fabrication of hierarchically ordered organic and inorganic hybrid structures at length scales ranging from nanometers to micrometers was demonstrated by oxygen plasma treatment of self-organized silicon-containing block copolymer films. The rod-coil type silicon-containing block copolymer, polystyrene-b-polyisoprene with polyhedral oligomeric silsesquioxane (POSS) -modified side chains, was successfully synthesized by hydrosilation of polystyrene-b-poly(1,2-ran-3,4-isoprene) block copolymer with hydrido-heptacyclopentyl substituted POSS. The films were prepared from the polymer solution by casting on silicon wafers under a moist air flow. The self-organized microstructures were investigated by electron microscopy. It was found that the hexagonally packed micropores and phase-separated nanodomains were formed within the films. Oxygen plasma etching of the films provided novel hierarchically ordered hybrid structures.

A rapid growth of mixed-signal integrated circuits is driving the needs of multifunction and miniaturization of the component in electronics applications. Polymer-ceramic composites have been of great interest as embedded capacitor materials because they enabled companies to combine the processability of polymers with the high dielectric constant of ceramics. Polymer-ceramic nanocomposites based on new concepts were developed for embedded capacitor applications. The dielectric constant was above 80 at 1 MHz and the specific capacitance was successfully achieved 8 nF/cm2. By use of this nanocomposites, multilayer printed wiring boards with embedded passive components were fabricated for prototypes. The following technologies are reported in this paper. Firstly, based on the investigation of barium titanium oxide (BaTiO3) crystallites, various particles with the sizes from 17 nm to 100 nm were prepared by the 2-step thermal decomposition method from barium titanyl oxalate (BaTiO(C2O4)2·4H2O). It was clarified that BaTiO3 particles with a size of around 70 nm exhibited a maximum dielectric constant of over 15,000 by FEM analysis from the measured dielectric constants of BaTiO3 suspensions. Secondary, the BaTiO3 surface modification based on a new concept was applied to improve the affinity between BaTiO3 particles and polymer matrix. Thirdly, the blend polymer of an aromatic polyamide (PA) and an aromatic bismaleimide (BMI) was employed as the matrix from a view-point of both the processabilty during fabricating the substrates with embedded passive components and the thermal stability during assembling LSI chips. Finally, these technologies were combined and optimized for embedded capacitor materials.