Mutation Analysis of 2009 Pandemic Influenza A(H1N1) Viruses Collected in Japan during the Peak Phase of the Pandemic

BACKGROUND: Pandemic influenza A(H1N1) virus infection quickly circulated worldwide in 2009. In Japan, the first case was reported in May 2009, one month after its outbreak in Mexico. Thereafter, A(H1N1) infection spread widely throughout the country. It is of great importance to profile and understand the situation regarding viral mutations and their circulation in Japan to accumulate a knowledge base and to prepare clinical response platforms before a second pandemic (pdm) wave emerges. METHODOLOGY: A total of 253 swab samples were collected from patients with influenza-like illness in the Osaka, Tokyo, and Chiba areas both in May 2009 and between October 2009 and January 2010. We analyzed partial sequences of the hemagglutinin (HA) and neuraminidase (NA) genes of the 2009 pdm influenza virus in the collected clinical samples. By phylogenetic analysis, we identified major variants of the 2009 pdm influenza virus and critical mutations associated with severe cases, including drug-resistance mutations. RESULTS AND CONCLUSIONS: Our sequence analysis has revealed that both HA-S220T and NA-N248D are major non-synonymous mutations that clearly discriminate the 2009 pdm influenza viruses identified in the very early phase (May 2009) from those found in the peak phase (October 2009 to January 2010) in Japan. By phylogenetic analysis, we found 14 micro-clades within the viruses collected during the peak phase. Among them, 12 were new micro-clades, while two were previously reported. Oseltamivir resistance-related mutations, i.e., NA-H275Y and NA-N295S, were also detected in sporadic cases in Osaka and Tokyo

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Impact of out-stent plaque characteristics on vascular response after second generation drug-eluting stent implantation: iMAP-intravascular ultrasound and angioscopic study

Purpose: The purpose of this study is to elucidate the impact of out-stent plaque characteristics on vascular response after implantation of second generation drug-eluting stent (G2-DES). Methods: Enrolled were 37 patients with 39 coronary artery lesions into which three types of G2-DES were successfully implanted (9 Nobori biolimus-, BES; 15 Xience everolimus-, EES; 15 Resolute zotarolimus-eluting stents; R-ZES). Immediately after (baseline) and one year after the implantation (follow-up), iMAP-intravascular ultrasound (IVUS) was performed to measure out-stent plaque volume (OSPV) and its components. Percent OSPV and vulnerable plaque index (VPI) were defined as percentile of OSPV to vessel volume and as percentile of lipidic plus necrotic volume to OSPV. Coronary angioscopy at follow-up rated the degree of arterial repair by neointimal stent coverage (NSC). Results: Poor NSC was found in approximately 60% of each G2-DES. In BES, % OSPV at baseline was significantly greater in poor NSC than in good NSC (36.2 ± 3.9 vs. 27.3 ± 4.0%, P = 0.01). In EES, %OSPV was significantly greater in poor NSC than in good NSC (41.0 ± 4.1 vs. 32.6 ± 2.7%, P < 0.01). In R-ZES implantation, there was no significant difference with regards to %OSPV between poor and good NSC. In BES, VPI at baseline was significantly greater in poor NSC than good NSC (54.0 ± 5.8 vs. 42.2 ± 5.1%, P = 0.02). There was no significant difference with regards to VPI between poor and good NCS in EES and R-ZES. Conclusions: Impact of out-stent plaque characteristics on vascular response was different among the three types of G2-DES. Keywords: Second generation drug-eluting stent, Arterial repair, Plaque characteristics, Intravascular ultrasound, Coronary angioscop

Oral direct renin inhibitor aliskiren reduces in vivo oxidative stress and serum matrix metalloproteinase-2 levels in patients with permanent atrial fibrillation

We aimed to determine the effects of the oral direct renin inhibitor aliskiren on in vivo oxidative stress in atrial fibrillation (AF) patients. In this study, 150 mg oral direct renin inhibitor aliskiren was administered once daily to 12 permanent AF patients. Aliskiren significantly reduced urinary excretion of the oxidative stress biomarker 8-iso-prostglandin F2α and serum levels of matrix metalloproteinase-2(MMP-2). We concluded that aliskiren reduces in vivo oxidative stress and serum MMP-2 levels in patients with permanent AF