Isolation and characterization of a virus (CvV-BW1) that infects symbiotic algae of Paramecium bursaria in Lake Biwa, Japan

<p>Abstract</p> <p>Background</p> <p>We performed an environmental study of viruses infecting the symbiotic single-celled algae of <it>Paramecium bursaria </it>(<it>Paramecium bursaria Chlorella </it>virus, PBCV) in Lake Biwa, the largest lake in Japan. The viruses detected were all <it>Chlorella variabilis </it>virus (CvV = NC64A virus). One of them, designated CvV-BW1, was subjected to further characterization.</p> <p>Results</p> <p>CvV-BW1 formed small plaques and had a linear DNA genome of 370 kb, as judged by pulsed-field gel electrophoresis. Restriction analysis indicated that CvV-BW1 DNA belongs to group H, one of the most resistant groups among CvV DNAs. Based on a phylogenetic tree constructed using the <it>dnapol </it>gene, CvV was classified into two clades, A and B. CvV-BW1 belonged to clade B, in contrast to all previously identified virus strains of group H that belonged to clade A.</p> <p>Conclusions</p> <p>We conclude that CvV-BW1 composes a distinct species within <it>C. variabilis </it>virus.</p

経動脈的化学塞栓術における予防的抗菌薬と肝膿瘍発症の関連 : 後方視的コホート研究

Objectives: Clinical evidence on prophylactic antibiotics for transarterial chemoembolization (TACE) to prevent liver abscess is limited because liver abscess is a rare event. This study aimed to analyse the association between prophylactic antibiotic use for TACE and the occurrence of liver abscess after TACE. Methods: Using the nationwide Diagnosis Procedure Combination database in Japan, we retrospectively identified patients who underwent TACE for hepatic cancer between July 2010 and March 2017. The primary outcome was liver abscess requiring procedural intervention within 30 days of TACE. Secondary outcomes included 30-day in-hospital mortality and length of stay. Propensity score matching was performed to adjust for potential confounding factors and compare outcomes between patients with and without prophylactic antibiotics. Results: Among 167 544 eligible patients, 134 712 received antibiotics and 32 832 did not. In the matched cohort of 29 211 pairs, the proportion of patients with liver abscess requiring procedural intervention was significantly lower in the antibiotics group than in the no-antibiotics group (0.08% vs. 0.22%, p 0.001; relative risk (95% confidence interval), 0.35 (0.22-0.57); absolute risk reduction, 0.0014 (0.0008-0.0021); and number needed to treat, 696 (476-1223)). There was no significant difference in 30-day in-hospital mortality between the groups. The length of stay was longer in the antibiotics group than in the no-antibiotics group (median, 10 vs. 9 days, p < 0.001). Conclusions: Prophylactic antibiotic use in patients undergoing TACE was associated with a reduced occurrence of liver abscess requiring procedural intervention.博士（医学）・甲第794号・令和3年6月25日Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved

Spatial Evolution of Wave‐Particle Interaction Region Deduced From Flash‐Type Auroras and Chorus‐Ray Tracing

In-situ observations of spatial variations of the wave-particle interaction region require a large number of satellite probes. As an alternative, flash-type auroras, a kind of pulsating aurora, driven by discrete chorus elements, can be used to investigate the interaction region with a high spatial resolution. We estimated the spatial extent of wave-particle interaction region from ground-based observations of flash aurora at Gakona (62.39°N, 214.78°E), Alaska at subauroral latitudes, and found that the auroral expansion was predominantly to the low-latitude side. The spatial displacement is thought to be caused by the propagation effects of chorus waves in the magnetosphere. Using ray tracing analysis to take into account chorus wave propagation, we reconstructed the spatiotemporal evolution of the volume emission rate and confirmed that the predominant expansion is toward the lower-latitude side in the ionosphere. This study shows that chorus wave propagation in the magnetosphere gives new insight for characterizing the transverse size (across the geomagnetic field line) of wave-particle interaction regions. The calculated spatial scale of the column auroral emission shows a correlation with the magnetic latitude of the resonance region at magnetic latitudes within 10° of the equatorial plane of the magnetosphere. Our results suggest that the spatial scale of a flash aurora is indirectly related to the chorus amplitude because the latitudinal range of the wave-particle interaction is important for the growth of wave amplitude

The Role of Eosinophils in Bullous Pemphigoid: A Developing Model of Eosinophil Pathogenicity in Mucocutaneous Disease

Bullous pemphigoid (BP) is an autoimmune blistering disease which carries a significant mortality and morbidity. While historically BP has been characterized as an IgG driven disease mediated by anti-BP180 and BP230 IgG autoantibodies, developments in recent years have further elucidated the role of eosinophils and IgE autoantibodies. In fact, eosinophil infiltration and eosinophilic spongiosis are prominent features in BP. Several observations support a pathogenic role of eosinophils in BP: IL-5, eotaxin, and eosinophil-colony stimulating factor are present in blister fluid; eosinophils line the dermo-epidermal junction (DEJ) in the presence of BP serum, metalloprotease-9 is released by eosinophils at the site of blisters; eosinophil degranulation proteins are found on the affected basement membrane zone as well as in serum corresponding with clinical disease; eosinophil extracellular DNA traps directed against the basement membrane zone are present, IL-5 activated eosinophils cause separation of the DEJ in the presence of BP serum; and eosinophils are the necessary cell required to drive anti-BP180 IgE mediated skin blistering. Still, it is likely that eosinophils contribute to the pathogenesis of BP in numerous other ways that have yet to be explored based on the known biology of eosinophils. We herein will review the role of eosinophils in BP and provide a framework for understanding eosinophil pathogenic mechanisms in mucocutaneous disease

Fractal analysis of subionospheric LF propagation data and consideration of the lithosphere-atmosphere-ionosphere coupling

Fractal analysis has been applied to the local nighttime data of subionospheric LF propagation, and the fractal dimension is estimated every day in the two distinct frequency ranges (AW: acoustic wave and AGW: atmospheric gravity wave). The data during several years are analyzed for the propagation paths from the Japanese transmitter of JJY to Moshiri (Hokkaido) and to Kochi. As the result of analysis, we come to the conclusion that when we pay attention to the period just around the earthquake, we sometimes detect some significant increases in the fractal dimension either in AW or AGW range. This indicates that the self – organization effect prior to an earthquake in the lithosphere, might be seen even in the lower ionosphere, probably in terms of atmospheric oscillation effect