日本の若年女性における一口量と咀嚼回数の関係

Objective: Modification of eating behavior in Japan is promoted to prevent overweight and obesity, but the effects of such modifications are unclear. This study aimed to clarify the inter- and intra-individual relationship between bite size and number of chews of food. Design and methods: Subjects comprised 50 young healthy Japanese women(mean age 19.5 years).Food materials were boiled rice and apple. First, the average bite size and the number of chews per mouthful of food were calculated across the study cohort. The number of chews was counted by subject’s own self and self-reported. Correlation between the individual one-bite volume and the number of chews per volume was analyzed using Spearman’s rank correlation coefficient. Second, the number of chews for three different sized bites of food (half of one bite, one bite, and one-and-a-half bites) were calculated as a prospective observational study. The number of chews for each of the three volumes of food was compared using one way ANOVA with Bonferroni correction. Results: For both food types, there was a negative correlation between individual mouthful volume and number of chews for both food materials. The number of chews per volume decreased as bite sizes increased. Conclusion: This study demonstrated an inter-and intra-individual relationship between bite size and the number of chews and suggested smaller bite sizes were associated with more chews per volume of food

Damage to inorganic materials illuminated by focused beam of X-ray free-electron laser radiation

X-ray free-electron lasers (XFELs) that utilize intense and ultra-short pulse X-rays may damage optical elements. We investigated the damage fluence thresholds of optical materials by using an XFEL focusing beam that had a power density sufficient to induce ablation phenomena. The 1 μ4m focusing beams with 5.5 keV and/or 10 keV photon energies were produced at the XFEL facility SACLA (SPring-8 Angstrom Compact free electron LAser). Test samples were irradiated with the focusing beams under normal and/or grazing incidence conditions. The samples were uncoated Si, synthetic silica glass (SiO2), and metal (Rh, Pt)-coated substrates, which are often used as X-ray mirror materials.Takahisa Koyama, Hirokatsu Yumoto, Kensuke Tono, Tadashi Togashi, Yuichi Inubushi, Tetsuo Katayama, Jangwoo Kim, Satoshi Matsuyama, Makina Yabashi, Kazuto Yamauchi, and Haruhiko Ohashi "Damage to inorganic materials illuminated by focused beam of x-ray free-electron laser radiation", Proc. SPIE 9511, Damage to VUV, EUV, and X-ray Optics V, 951107 (12 May 2015); https://doi.org/10.1117/12.218277

Damage threshold of coating materials on x-ray mirror for x-ray free electron laser

We evaluated the damage threshold of coating materials such as Mo, Ru, Rh, W, and Pt on Si substrates, and that of uncoated Si substrate, for mirror optics of X-ray free electron lasers (XFELs). Focused 1 μm (full width at half maximum) XFEL pulses with the energies of 5.5 and 10 keV, generated by the SPring-8 angstrom compact free electron laser (SACLA), were irradiated under the grazing incidence condition. The damage thresholds were evaluated by in situ measurements of X-ray reflectivity degradation during irradiation by multiple pulses. The measured damage fluences below the critical angles were sufficiently high compared with the unfocused SACLA beam fluence. Rh coating was adopted for two mirror systems of SACLA. One system was a beamline transport mirror system that was partially coated with Rh for optional utilization of a pink beam in the photon energy range of more than 20 keV. The other was an improved version of the 1 μm focusing mirror system, and no damage was observed after one year of operation.Takahisa Koyama, Hirokatsu Yumoto, Takanori Miura, Kensuke Tono, Tadashi Togashi, Yuichi Inubushi, Tetsuo Katayama, Jangwoo Kim, Satoshi Matsuyama, Makina Yabashi, Kazuto Yamauchi, and Haruhiko Ohashi, "Damage threshold of coating materials on x-ray mirror for x-ray free electron laser", Review of Scientific Instruments 87, 051801 (2016) https://doi.org/10.1063/1.4950723

Histological Study of the Left Atrial Wall: A Consideration of the Compound Myocardial Architecture and Potential Durability with Respect to Catheter Ablation in Pulmonary Vein Isolation Procedures

Pulmonary vein isolation using radiofrequency energy is performed extensively to treat symptomatic, drug-refractory atrial fibrillation. However, anatomical knowledge of the left atrial wall surrounding the pulmonary vein (PV) openings is insufficient to create an ablation line. Using autopsy hearts from 23 individuals (median age of 63 years), we studied the histological nature of anatomical obstacles or related isthmuses near the PV openings. None of the individuals had a history of tachyarrhythmia or other major cardiac abnormalities. After macroscopic measurement of the minimum width of each isthmus, the following areas were excised and histologically prepared: atrial roof-mitral valve annulus (MVA), left superior pulmonary vein (LSPV) -left atrial appendage (LAA), LAA-MVA, left inferior pulmonary vein (LIPV) -MVA, right superior pulmonary vein (RSPV) -fossa ovalis (FO), right inferior pulmonary vein (RIPV) -FO, and FO-MVA. Within the obstacles near the PV openings, the LSPV-LAA isthmus was found to be the narrowest, whereas the LIPV-MVA was the widest and thickest isthmus. Histological complexity of each isthmus was determined, and the compound architecture of the myocardium was revealed. The further presence of a variety of nerve endings as well as myocardial blood supply enhanced the tissue diversity. Such an insight into the diversity of myocardial architecture or histological complexity in each isthmus might be helpful in creating a reliable ablation line in pulmonary vein isolation procedures

Radiation-induced Liver Injury after 3D-conformal Radiotherapy for Hepatocellular Carcinoma: Quantitative Assessment Using Gd-EOB-DTPA-enhanced MRI

Focal liver reaction (FLR) appears in the hepatobiliary-phase images of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI) following radiotherapy (RT). We investigated the threshold dose (TD) for FLR development in 13 patients with hepatocellular carcinoma (HCC) who underwent three-dimensional conformal radiotherapy (3D-CRT) with 45 Gy in 15 fractions. FLR volumes (FLRVs) were calculated based on planning CT images by referring to fused hepatobiliary-phase images. We also calculated the TD and the irradiated volumes (IVs) of the liver parenchyma at a given dose of every 5 Gy (IVdose) based on a dose-volume histogram (DVH). The median TD was 35.2 Gy. The median IV20, IV25, IV30, IV35, IV40, and IV45 values were 371.1, 274.8, 233.4, 188.6, 145.8, and 31.0 ml, respectively. The median FLRV was 144.9 ml. There was a significant difference between the FLRV and IV20, IV25, and IV45 (p<0.05), but no significant differences between the FLRV and IV30, IV35, or IV40. These results suggest that the threshold dose of the FLR is approx. 35 Gy in HCC patients who undergo 3D-CRT in 15 fractions. The percentage of the whole liver volume receiving a dose of more than 30-40 Gy (V30-40) is a potential candidate optimal DVH parameter for this fractionation schedule

Lack of Grafted Liver Rejuvenation in Adult-to-Pediatric Liver Transplantation.

BACKGROUND: A grafted donor liver should grow and survive under the different conditions presented by a liver transplantation recipient. It has remained unclear, however, whether the age of a grafted liver can be modulated by recipient factors. AIMS: This study investigated whether a grafted aged donor liver can be rejuvenated in a pediatric recipient. METHODS: Of 119 living donor liver transplants, ten pairs were adult-to-pediatric combinations. Senescence marker protein-30 (SMP-30), which is a protein that is remarkably reduced upon aging, was used as a senescence marker. Immunohistochemical staining for SMP-30 was performed in biopsy specimen after living donor liver transplantation (LDLT). Re-expression of SMP-30 was investigated in a biopsied adult liver (n = 6) that had been transplanted in a pediatric recipient. RESULTS: A remarkable expression of SMP-30 was seen in a control pediatric normal liver in comparison with that in an aged adult donor biopsy. Re-expression or an increase in SMP-30 was not observed in the liver of any pediatric recipient who had received an adult liver. CONCLUSION: An adult grafted liver does not appear to rejuvenate in a pediatric recipient

Susceptibility of muridae cell lines to ecotropic murine leukemia virus and the cationic amino acid transporter 1 viral receptor sequences: implications for evolution of the viral receptor

Ecotropic murine leukemia viruses (Eco-MLVs) infect mouse and rat, but not other mammalian cells, and gain access for infection through binding the cationic amino acid transporter 1 (CAT1). Glycosylation of the rat and hamster CAT1s inhibits Eco-MLV infection, and treatment of rat and hamster cells with a glycosylation inhibitor, tunicamycin, enhances Eco-MLV infection. Although the mouse CAT1 is also glycosylated, it does not inhibit Eco-MLV infection. Comparison of amino acid sequences between the rat and mouse CAT1s shows amino acid insertions in the rat protein near the Eco-MLV-binding motif. In addition to the insertion present in the rat CAT1, the hamster CAT1 has additional amino acid insertions. In contrast, tunicamycin treatment of mink and human cells does not elevate the infection, because their CAT1s do not have the Eco-MLV-binding motif. To define the evolutionary pathway of the Eco-MLV receptor, we analyzed CAT1 sequences and susceptibility to Eco-MLV infection of other several murinae animals, including the southern vole (Microtus rossiaemeridionalis), large Japanese field mouse (Apodemus speciosus), and Eurasian harvest mouse ( Micromys minutus). Eco-MLV infection was enhanced by tunicamycin in these cells, and their CAT1 sequences have the insertions like the hamster CAT1. Phylogenetic analysis of mammalian CAT1s suggested that the ancestral CAT1 does not have the Eco-MLV-binding motif, like the human CAT1, and the mouse CAT1 is thought to be generated by the amino acid deletions in the third extracellular loop of CAT1