Plant viruses and viroids in Japan

An increasing number of plant viruses and viroids have been reported from all over the world due largely to metavirogenomics approaches with technological innovation. Herein, the official changes of virus taxonomy, including the establishment of megataxonomy and amendments of the codes of virus classification and nomenclature, recently made by the International Committee on Taxonomy of Viruses were summarized. The continued efforts of the plant virology community of Japan to index all plant viruses and viroids occurring in Japan, which represent 407 viruses, including 303 virus species and 104 unclassified viruses, and 25 viroids, including 20 species and 5 unclassified viroids, as of October 2021, were also introduced. These viruses and viroids are collectively classified into 81 genera within 26 families of 3 kingdoms (Shotokuvirae, Orthornavirae, Pararnavirae) across 2 realms (Monodnaviria and Riboviria). This review also overviewed how Japan’s plant virus/viroid studies have contributed to advance virus/viroid taxonomy

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Virus-Induced Gene Silencing in <i>Chrysanthemum seticuspe</i> Using the Tomato Aspermy Virus Vector

Chrysanthemum is one of the most economically important flowers globally due to its high ornamental value. In recent years, a large percentage of the Chrysanthemum seticuspe genome has been determined, making this species useful as a model chrysanthemum plant. To fully utilize the genome’s information, efficient and rapid gene functional analysis methods are needed. In this study, we optimized the tomato aspermy virus (TAV) vector for virus-induced gene silencing (VIGS) in C. seticuspe. Conventional plant virus inoculation methods, such as the mechanical inoculation of viral RNA transcripts and agroinoculation into leaves, did not achieve successful TAV infections in C. seticuspe, but vacuum infiltration into sprouts was successful without symptoms. The TAV vector harboring 100 nucleotides of the phytoene desaturase (PDS) gene caused photobleaching phenotypes and a reduction in CsPDS expression in C. seticuspe. To our knowledge, this is the first report of VIGS in chrysanthemums

First characterisation of chrysanthemum virus B infecting chrysanthemum in Thailand and development of colourimetric RT-LAMP for rapid and sensitive detection

Chrysanthemum is among the world's most important ornamental plants because of its high economic and cultural value. Our report is the first to describe the detection of chrysanthemum virus B (CVB) in chrysanthemum leaf samples collected from Thailand, which showed yellowing and mild mottling symptoms. The coat protein sequences of CVB isolated in this study share 95.15% identity with previously characterised CVB isolates. Biological indexing found that CVB induced both local and systemic symptoms in tobacco plants, while petunia displayed systemic symptoms. To improve the rapidity and sensitivity of CVB detection, the loop-mediated isothermal amplification (LAMP) technique was developed. LAMP detection was found to be optimal when incubation was conducted at 65 °C for 45 min, wherein the LAMP reaction demonstrated 106 times higher sensitivity than polymerase chain reaction. To simplify the interpretation of results, we designed the method such that a positive result is clearly indicated based on a change of colour (colourimetry), from pink to yellow, as observed visually and via gel electrophoresis. To our best knowledge, this is the first report on the characterisation of molecular, biological and morphological characteristics of CVB infecting chrysanthemum in Thailand, along with the development of colourimetric RT-LAMP for improving detection efficiency

Impact of dapagliflozin on left ventricular diastolic function of patients with type 2 diabetic mellitus with chronic heart failure

Abstract Background The objective of this study was to investigate the impact of sodium glucose cotransporter type 2 (SGLT2) inhibitors on left ventricular (LV) diastolic function of type 2 diabetes mellitus (T2DM) patients with heart failure (HF). Methods This trial was a prospective multicenter study of 58 T2DM patients with stable HF at five institutions in Japan. Patients who had been taking at least one antidiabetic drugs other than SGLT2 inhibitors started the administration of 5 mg/day of dapagliflozin. The physical examinations, blood tests, and echocardiography were performed at baseline and 6 months after administration of dapagliflozin. The primary endpoint was defined as a change in mitral inflow E and mitral e′ annular velocities (E/e′) between baseline and 6 months after the administration of dapagliflozin. The secondary end points consisted of a change in brain natriuretic peptide (BNP), LV mass index (LVMI) and left atrial volume index (LAVI). Results E/e′ significantly decreased from 9.3 to 8.5 cm/s (p = 0.020) 6 months after administration of dapagliflozin. LAVI and LVMI significantly decreased from 31 to 26 mL/m2 (p = 0.001), and from 75.0 to 67.0 g/m2 (p < 0.001), respectively, 6 months after administration of dapagliflozin. No significant change was observed in BNP (from 27.9 to 28.9 pg/mL; p = 0.132) 6 months after administration of dapagliflozin, except for a significant decrease from 168.8 to 114.3 pg/mL (p = 0.012) in patients with BNP ≥ 100 pg/mL. Conclusion This prospective multicenter trial showed the beneficial effect of SGLT2 inhibitors on LV diastolic functional parameters for T2DM patients with HF. Our findings may thus offer a new insight into the management of T2DM patients. Trial registration UMIN000019789, Registered 28 September 2014, Date of registration: 11/14/2015, Date of enrolment of the first participant to the trial: 6/15/2016, Date of enrolment of the last participant to the trial: 12/9/201