[en] In our proposed method of the completely electrodeless electric propulsion system, a high-density (∼ 10"1"3 cm"-"3 ) helicon plasma is accelerated by the Lorentz force, i.e., the product of the azimuthal current j_θ and the radial component of magnetic field B_r. In order to promote the plasma acceleration scheme, we used permanent magnets (PMs) designed to increase B_r in comparison to the present electromagnets (EMs). As an initial try of the plasma acceleration by our system, electron density n_e and ion velocity v_i of generated plasma using PMs' magnetic field were measured, and we have obtained the maximum value of n_e = 2.5 × 10"1"2 cm"-"3 and v_i = 2.2 km/s. In addition, we have also introduced a combined, flexible operation of using PMs and EMs leading to better plasma performance. (author)

[en] In order to establish a completely electrodeless electric thruster, we have been studying the proposed electromagnetic acceleration methods, and estimating plasma performance using various diagnostics. Plasma thrust is the most important feature of the thruster; therefore estimation of the plasma thrust is necessary. In this study, we have developed a pendulum-target-type plasma thrust stand. Our experiment uses a Large Mirror Device and a high-power radiofrequency source (7 MHz, ∼5 kW) to produce high-density helicon plasma. The thruster uses both permanent magnets and electromagnets for generating magnetic field with a large radial component to increase electromagnetic acceleration by the proposed method of including an azimuthal current. In this paper, details of the developed thrust stand and experimental results for thrust, thrust efficiency and specific impulse are presented. (author)

[en] Portal vein tumor thrombosis (PVTT) and inferior vena cava tumor thrombosis (IVCTT) in hepatocellular carcinoma (HCC) are oncological emergent conditions. However, there have been no effective treatments for unresectable HCC with PVTT and/or IVCTT. Eleven HCC patients with IVCTT (n=5) and PVTT (n=6), who underwent radiation therapy (RT) for the thrombi as a palliative therapy, were reviewed. All of the patients had no indications for resection, local therapies and TACE. The total radiation dose was 39-60 Gy (median, 50 Gy). The response rate and time to progression of the thrombi, overall survival and the toxicity were analyzed. Of the 5 patients with IVCTT, the tumor thrombus completely disappeared in 1 patient, 2 patients had a partial response, and 2 patients had stable disease. Of the 6 patients with PVTT, 1 patient had a partial response, 2 patients had stable disease, and 2 patients had progressive disease. The response rate was 60% and 16.7% in IVCTT and PVTT patients respectively. The median survival was 401 days in IVCTT patients and 374 days in PVTT patients. A patient with IVCTT suffered from grade 2 pneumonitis, successfully treated with antibiotics. Radiotherapy (RT) can be a treatment of choice for IVCTT in unresectable HCC patients, but the effects were limited for PVTT. (author)

[en] It is difficult to induce the maturation of embryonic stem (ES) cells into hepatocytes in vitro. We previously reported that Thy1-positive mesenchymal cells derived from the mouse fetal liver promote the maturation of hepatic progenitor cells. Here, we isolated alpha-fetoprotein (AFP)-producing cells from mouse ES cells for subsequent differentiation into hepatocytes in vitro by coculture with Thy1-positive cells. ES cells expressing green fluorescent protein (GFP) under the control of an AFP promoter were cultured under serum- and feeder layer-free culture conditions. The proportion of GFP-positive cells plateaued at 41.6 ± 12.2% (means ± SD) by day 7. GFP-positive cells, isolated by flow cytometry, were cultured in the presence or absence of Thy1-positive cells as a feeder layer. Isolated GFP-positive cells were stained for AFP, Foxa2, and albumin. The expression of mRNAs encoding tyrosine amino transferase, tryptophan 2,3-dioxygenase, and glucose-6-phosphatase were only detected following coculture with Thy1-positive cells. Following coculture with Thy1-positive cells, the isolated cells produced and stored glycogen. Ammonia clearance activity was also enhanced following coculture. Electron microscopic analysis indicated that the cocultured cells exhibited the morphologic features of mature hepatocytes. In conclusion, coculture with Thy1-positive cells in vitro induced the maturation of AFP-producing cells isolated from ES cell cultures into hepatocytes