Acetyl-L-carnitine suppresses thyroid hormone-induced and spontaneous anuran tadpole tail shortening

Mitochondrial membrane permeability transition (MPT) plays a crucial role in apoptotic tail shortening during anuran metamor phosis. L-carnitine is known to shuttle free fatty acids (FFAs) from the cytosol into mitochondria matrix for -oxidation and energy production, and in a previous study we found that treatment with L-carnitine suppresses 3, 3', 5-triiodothyronine (T3) and FFA-induced MPT by reducing the level of FFAs. In the present study we focus on acetyl-L-carnitine, which is also involved in fatty acid oxidation, to determine its effect on T3-induced tail regression in Rana rugosa tadpoles and spontaneous tail regression in Xenopus laevis tadpoles. The ladder-like DNA profile and increases in caspase-3 and caspase-9 indicative of apoptosis in the tails of T3-treated tadpoles were found to be suppressed by the addition of acetyl-L-carnitine. Likewise, acetyl-L-carnitine was found to inhibit thyroid hormone regulated spontaneous metamorphosis in X. laevis tadpoles, accompanied by decreases in caspase and phospholipase A2 activity, as well as non-ladder-like DNA profiles. These findings support our previous conclusion that elevated levels of FFAs initiate MPT and activate the signaling pathway controlling apoptotic cell death in tadpole tails during anuran metamorphosis

Detection and management of cardiomyopathy in female dystrophinopathy carriers

Regular health checkups for mothers of patients with Duchenne muscular dystrophy have been performed at National Hospital Organization Tokushima Hospital since 1994. Among 43 mothers participated in this study, 28 dystrophinopathy carriers were identified. Skeletal and cardiac muscle functions of these subjects were examined. High serum creatine kinase was found in 23 subjects (82.1%). Obvious muscle weakness was present in 5 (17.8%) and had progressed from 1994 to 2015. Cardiomyopathy was observed in 15 subjects (60.0%), including dilated cardiomyopathy-like damage that was more common in the left ventricular (LV) posterior wall. Late gadolinium enhancement on cardiac MRI was found in 5 of 6 subjects, suggesting fibrotic cardiac muscle. In speckle tracking echocardiography performed seven years later, global longitudinal strain was decreased in these subjects, indicating LV myocardial contractile abnormality. These results suggest that female dystrophinopathy carriers should receive regular checkups for detection and treatment of cardiomyopathy, even if they have no cardiac symptoms

International comparison of subclinical atherosclerosis among the Japanese and American men aged 40-49

科学研究費補助金研究成果報告書研究種目: 基盤研究(A)研究期間: 2001～2004課題番号: 13307016研究代表者: 上島 弘嗣（滋賀医科大学・医学部・教授）研究分担者: 三ッ浪 健一（滋賀医科大学・医学部・教授）研究分担者: 村田 喜代史（滋賀医科大学・医学部・教授）研究分担者: 中村 保幸（滋賀医科大学・医学部・助教授）研究分担者: 柏木 厚典（滋賀医科大学・医学部・教授）研究分担者: 岡村 智教（滋賀医科大学・医学部・助教授）研究分担者: 喜多 義邦（滋賀医科大学・医学部・助手）研究分担者: 門脇 崇（滋賀医科大学・医学部・助手

Low-charge-state ion production by a laser ion source for the TIARA ion implanter

Ion implanters require various kinds of heavy-ion beams in low-charge states for material science experiments. For this purpose, a laser ion source has been developed for the ion implanter at Takasaki Ion Accelerators for Advanced Radiation Application. In this study, we investigated the particle number of ions per laser pulse for each charge state in the laser-produced carbon plasma. In the experiment, the carbon plasma was generated from a graphite target using a Nd:YAG laser (1064 nm wavelength, 5 ns pulse width) at a laser energy of 37.5 mJ, 28.3 mJ, or 15.6 mJ. The particle number of ions in the plasma was evaluated from the time-integrated value of each ion-charge-state\u27s current signal by placing the focusing lens at various positions. We found that the particle number of carbon ions was highest for singly charged ions at all laser energies, with particle number on the order of 10^10 ions obtained at a 1-m distance from the target surface

Investigation of the time interval of plasma generation for a high repetition rate laser ion source

To apply a laser ion source that generates a high-intensity pulsed beam to high-dose applications, such as ion implantation, a high repetition rate operation with a short pulse interval is required. However, when the pulse interval is shortened, there is a concern that a plasma, which is different from a single pulse plasma generation, may be formed due to the interaction between the preceding and following pulses. We investigated the time interval in which plasma pulses are generated without pulse-to-pulse interaction using a laser ion source with two lasers. In the experiment, a graphite target was irradiated by two laser beams (1064-nm wavelengths) with the same pulse widths (5.4 ns) and energies (15 mJ, 30 mJ, and 45 mJ) at different time intervals ranging from 1000 μs to 0 μs, and the time integrated value corresponding to the total charge amount was calculated from the measured time-of-flight signal of the generated carbon ion current. It was observed that the total charge did not change when the time interval was as low as approximately 100 μs, and the total charge rapidly decreased when the time interval was below approximately 100 μs. Thus, it was determined that the interaction occurs within a time interval of approximately 100 μs

Measurement of Hydrogen Ion Beam Energy Spreads Generated by a Penning-Ionization-Gauge Type Ion Source with Electric Magnets for a MeV Compact Ion Microbeam System

本研究では、イオンマイクロビームの産業利用を目指して開発中の小型イオンマイクロビーム装置の要素技術として、小型・小電力な電磁石型PIGイオン源（emPIGイオン源）を開発している。このイオン源は、マイクロビーム形成に必要な低エネルギー、高輝度及び小エネルギー幅のイオンビームを発生するため、微小体積の高密度プラズマからイオンビームを引き出す方式である。これまでに、emPIGイオン源から300eV程度で高輝度な水素イオンビームが発生できることを実験的に示した。今回、もう一つの重要なビーム条件である小エネルギー幅のビームを発生するため、イオン源の引き出し電圧、水素ガス圧及び磁場強度を変えてエネルギー幅を静電並行平板型のエネルギー分析器により測定した。この結果、300eV程度の水素イオンビームで、6eV程度の最低エネルギー幅が得られ、ほぼ目標値を達成することができた。The 17th International Conference on Ion Source

Preliminary Study: Measurement of Ion Beam Energy Spreads Produced by a Penning Ionization Gauge-Type Ion Source Using Electromagnets for a Mega-electron Volt Compact Ion Microbeam System

The energy spreads of ion beams generated from a penning ionization gauge-type ion source with electromagnets were measured using a parallel electrostatic analyzer. The ion source was developed to be installed in a mega-electron volt (MeV) compact ion microbeam system.A gaseous ion beam of expectedly high brightness and narrow energy spread was generated from the ion source to form a microbeam. To produce such an ion beam, a high-density plasma with a small volume was generated using a strong magnetic field in the ion source. The beam energy spread width was of particular importance because it forms an ion microbeam by reducing the chromatic aberration at a focusing lens.In this report, the energy spread was investigated by changing the parameters of the ion source, e.g., extraction voltage, excitation current of electromagnets, vacuum, and anode voltage. The investigation showed that spread widths are influenced by the extraction voltage, vacuum,and anode voltage. The minimum width of∼5.0±0.1 eV was obtained at a beam energy of 200 eV. This value is acceptable for the MeV compact ion microbeam system