D-Shuttle project: measurement and comparison of individual doses of high school students.

In 2014, a team of high school students and teachers measured individual exposure doses using D-Shuttle dosimeters. In total, 216 students and teachers participated in the project, with the cooperation of 12 high schools in Japan (six from Fukushima Prefecture), four from France, eight from Poland, and two from Belarus. The participants wore the dosimeters for 2 weeks and recorded their locations in diary charts. The distribution of annual exposure doses for each school and region, estimated from the measured results, overlapped. It was concluded that the external exposure of high school students in Fukushima Prefecture was not markedly higher compared with that of students from other regions.

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project.

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Terahertz optical clock generation with tunable repetition rate and central wavelength using variable-bandwidth spectrum shaper.

Recently, a number of high-speed optical clock generation technologies have been developed due to their potential useful applications in different fields. Here, we propose a new terahertz optical clock generation technique with tunable repetition rate and central wavelength. The proposed optical clock generator consists of an frequency comb light source and a variable-bandwidth spectrum shaper (VBS). The VBS can generate arbitrary repetition rate pulse trains and waveform by controlling each spectral mode. We experimentally demonstrated optical clock generation with repetition rates of 1.28, 2.56, 3.0, and 4.0 THz.

Long-term potentiation and olfactory memory formation in the carp (Cyprinus carpio L.) olfactory bulb.

Long-term potentiation of synaptic transmission is considered to be an elementary process underlying the cellular mechanism of memory formation. In the present study we aimed to examine whether or not the dendrodendritic mitral-to-granule cell synapses in the carp olfactory bulb show plastic changes after their repeated activation. It was found that: (1) the dendrodendritic mitral-to-granule cell synapses showed three types of plasticity after tetanic electrical stimulation applied to the olfactory tract-long-term potentiation (potentiation lasting >1 h), short-term potentiation (potentiation lasting <1 h) and post-tetanic potentiation (potentiation lasting <10 min); (2) Long-term potentiation was generally induced when both the dendrodendritic mitral-to-granule cell synapses and centrifugal fiber-to-granule cell synapses were repeatedly and simultaneously activated; (3) long-term enhancement (>1 h) of the odor-evoked bulbar response accompanied the electrically-induced LTP, and; (4) repeated olfactory stimulation enhanced dendrodendritic mitral-to-granule cell transmission. Based on these results, it was proposed that long-term potentiation (as well as olfactory memory) occurs at the dendrodendritic mitral-to-granule cell synapses after strong and long-lasting depolarization of granule cells, which follows repeated and simultaneous synaptic activation of both the peripheral and deep dendrites (or somata).

Synthesis of symmetrical polynitrohelicenes and their chiral recognition in the charge transfer complexation.

Derivatives of optically active 1,12-dimethylbenzo[c]phenanthrene-5,8-dicarboxylic acid can be nitrated regioselectively, giving symmetrically polyfunctionalized helicenes. The dicarboxylic acid or its dimethyl ester is dinitrated with fuming nitric acid in acetic acid at the 4,9-positions. When the reaction is conducted in fuming nitric acid, a 2,4,9,11-tetranitrohelicene is obtained. Analogously, 1,12-dimethylbenzo[c]phenanthrene-5,8-dinitrile gives 2,11-dinitro- or 4,9-dinitrohelicene depending on the conditions, and the former compound is converted to a 2,4,9,11-tetranitrohelicene. The tetranitrohelicenes form charge-transfer (CT) complexes with an electron-rich chiral diaminohelicene in solution. The studies on the chiral recognition reveal that the combinations of the same configuration of the helicenes form more stable complexes than that of the enantiomeric helicenes.

Postoperative hyponatremia in a patient with ACTH-producing Merkel cell carcinoma.

Merkel cell carcinoma is characterized by specific neuroendocrine features and the expression of several neuropeptides. We report a case of Merkel cell carcinoma with post-surgical hyponatremia in an 85-year-old Japanese woman. A tumor on the left cheek histopathologically showed the characteristics of Merkel cell carcinoma together with Bowen's disease. Although an increased level of ACTH was found both in the tumor and in the peripheral blood, the postoperative hyponatremia in our patient seems more likely to have been caused by the stress of the operation and indapamide, considering that the ACTH level in the tumor was much lower than those in other ectopic ACTH-producing tumors in previous reports.

Effect of amino acid substitution in amphiphilic alpha-helical peptides on peptide-phospholipid membrane interaction.

It was previously found that a cationic amphiphilic peptide, Ac-(Leu-Ala-Arg-Leu)3-NHCH3 (4(3)), caused the destabilization of a phospholipid membrane and showed strong antibacterial activity [Lee et al. Biochim. Biophys. Acta 1986; 862: 211-219]. In order to investigate the effect of changing alpha-helix propensity, hydrophobicity and basicity in 4(3) on the peptide conformation and activity, the 4(3) analogs, [Gly (or Val)6]4(3), [Gly (or Val)2,6]4(3), [Gly (or Val)2,6,10]4(3), [Gln3]4(3), [Gln3,7]4(3) and [Gln3,7,11]4(3) were synthesized. Except for [Val2,6]4(3) and [Val2,6,10]4(3), which mainly formed a beta-structure, other peptides formed an alpha-helix and showed moderate membrane-perturbing activity toward neutral and acidic lipid vesicles. All the peptides other than [Val2,6,10]4(3) and [Gln3,7,10]4(3) had the antibacterial activity comparable with that of 4(3). The relationship between the membrane-perturbing activity and the antibacterial activity was not always parallel. Conclusively, the Ala-->Val substitution in 4(3) causes the change of peptide conformation and the presence of a cationic amino acid residue is necessary for the antibacterial activity.

Squamous cell carcinoma in a renal transplant recipient with linear porokeratosis.

A 40-year-old man developed squamous cell carcinoma on a perianal lesion of linear porokeratosis after renal transplantation. The tumor metastasized to the left inguinal lymph node 25 months after the primary tumor was excised. p53 overexpression was observed in the tumor cells, but not in the porokeratotic lesion. Interestingly, continuous subcutaneous infusion of peplomycin for the lymph node metastasis significantly improved the warty lesions of porokeratosis. In this patient, immunosuppressive agents might have accelerated the development of carcinoma on a skin area with malignant potential.

Enhancement of radical intensity and cytotoxic activity of ascorbate by Crataegus cuneata Sieb et. Zucc. extracts.

The radical modulation activity of hot water and NaOH extracts of the thorn apple of Crataegus Cuneata Sieb. et. Zucc. was investigated, using ESR spectroscopy. The radical intensity of sodium ascorbate was slightly reduced at lower concentrations of the extracts, but it was synergistically enhanced at higher concentrations. Higher concentrations of the extracts also synergistically stimulated the cytotoxic action of sodium ascorbate against human oral squamous carcinoma and salivary gland tumor cell lines. All these extracts effectively scavenged superoxide anion and hydroxyl radical, produced by hypoxanthine-xanthine oxidase and Fenton reaction, respectively, and their activity was comparable with that of lignins prepared by the same procedure from other plants. These data further supports the medicinal efficacy of plant extracts.

Radical scavenging activity of Acer nikoense Maxim. extract.

The effect of hot water and alkaline extracts of Acer nikoense Maxim. on the radical intensity of sodium ascorbate, superoxide anion (O2-)(produced by hypoxanthine-xanthine oxidase reaction) and hydroxyl radical (-OH)(generated by Fenton reaction) was investigated using ESR spectroscopy. All these extracts produced radical(s) under alkaline conditions and enhanced the radical intensity of sodium ascorbate. Among these fractions, Fr. I showed the highest stimulation effect, which coincided with its higher degradation rate and capacity to enhance the cytotoxic activity of ascorbate. These fractions also dose-dependently reduced the radical intensity of O2- and -OH. The present study demonstrates that Acer nikoense Maxim. extracts potentiate both radical intensity and apoptosis-inducing activity of ascorbate.

Pretibial myxedema with Graves' disease: a case report and review of Japanese literature.

We report a case of pretibial myxedema with Graves' disease in an 18-year-old Japanese woman. The physical examination revealed waxy indurated plaques with prominent hair follicle openings and nonpitting edema disseminated on her lower legs. Histology from an edematous lesion revealed that the dermis was markedly thickened with abundant mucin, especially hyaluronic acid, and the collagen fibers in this portion were splitting up into fibrils. We also reviewed 112 cases of pretibial myxedema reported in the Japanese literature.

Dermatomyositis associated with primary intramuscular B cell lymphoma.

A rare case of dermatomyositis associated with primary intramuscular malignant lymphoma is described. A 40-year-old Japanese woman noticed swelling of the right thigh during the treatment of dermatomyositis with prednisolone, azathioprine and cyclophosphamide. A biopsy specimen taken from the right quadriceps muscle revealed infiltration of lymphoma cells which were positive for CD20. We reviewed 12 cases of dermatomyositis associated with malignant lymphoma reported in Japanese literature between 1984 and 1996.

Enhancement of cytotoxic activity of ascorbate by Acer nikoense Maxim. Extracts.

Millimolar concentrations of ascorbic acid or sodium ascorbate induced cytotoxicity against human glioblastoma T98G cells. Addition of hot water and sodium hydroxide extracts of the bark of Acer nikoense Maxim. synergistically enhanced the cytotoxic activity of ascorbate. Human peripheral blood lymphocytes and polymorphonuclear cells were relatively resistant to ascorbate, the Acer nikoense Maxim. extract, or a combination of them. The extracts stimulated the degradation of ascorbates via ascorbyl radical production, in parallel with their ability to stimulate the cytotoxic activity of ascorbate. The results suggest the medicinal efficacy of the Acer nikoense Maxim. extracts.

[Intermittent-dose ara-C/daunomycin therapy combined with cyclosporin-A and G-CSF led to a fourth remission in a patient with acute promyelocytic leukemia].

A 50-year-old female was admitted with acute promyelocytic leukemia (APL) in August, 1988. She was treated with behenoyl-ara-C, daunomycin, 6-mercaptopurine and prednisolone (BH-AC.DMP), which led to a complete remission. Thereafter, she was treated with 2 courses of BH-AC.DM and discharged from hospital. Intensification therapy was performed twice a year, with 1 course of BH-AC.DM and 5 courses of intermittent-dose ara-C/mitoxantrone which ended in March, 1992. She had a relapse in September, 1993 and was treated with all-trans retinoic acid, which led to a second remission. A second relapse occurred in May, 1994, and intermittent-dose ara-C/mitoxantrone, combined with granulocyte colony-stimulating factor (G-CSF), led to a third remission. However, she had a third relapse in September, 1994. She was treated with a trial of G-CSF (300 micrograms/body, day 1-7), to stimulate dormant leukemic cells to enter the cell cycle, and cyclosporin-A (78 mg/kg, day 2-5), in order to overcome daunomycin resistance in refractory leukemia, combined with daunomycin (45 mg/m2, day 3-5) and ara-C (1.4 g/m2, day 3-7), after obtaining informed consent. The fourth remission needed 46 days after combination chemotherapy because of severe myelosuppression. It was suggested that intermittent-dose ara-C/daunomycin therapy combined with G-CSF and cyclosporin-A may be useful for relapsed and refractory leukemia.