Publications by authors named "Takasugi N"

Background: Atrial fibrillation (AF) and heart failure (HF) often coexist, leading to increased mortality. A cryoballoon-based approach is a potential treatment for patients with HF because of its safety and efficacy.

Objectives: The authors sought to evaluate the optimal timing of cryoballoon ablation after the first clinical diagnosis of AF and its prognosis for patients with HF.

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Inositol-requiring enzyme 1α (IRE1α) is a sensor of endoplasmic reticulum (ER) stress and drives ER stress response pathways. Activated IRE1α exhibits RNase activity and cleaves mRNA encoding X-box binding protein 1, a transcription factor that induces the expression of genes that maintain ER proteostasis for cell survival. Previously, we showed that IRE1α undergoes -nitrosylation, a post-translational modification induced by nitric oxide (NO), resulting in reduced RNase activity.

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Ubiquitously distributed environmental electrophiles covalently modify DNA and proteins, potentially leading to adverse health effects. However, the impacts of specific electrophiles on target proteins and their physiological roles remain largely unknown. In the present study, we focused on DNA methylation, which regulates gene expression and physiological responses.

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Methylmercury (MeHg) is an environmental neurotoxin that induces damage to the central nervous system and is the causative agent in Minamata disease. The mechanisms underlying MeHg neurotoxicity remain largely unknown, and there is a need for effective therapeutic agents, such as those that target MeHg-induced endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), which is activated as a defense mechanism. We investigated whether intraperitoneal administration of the chemical chaperone, 4-phenylbutyric acid (4-PBA), at 120 mg/kg/day can alleviate neurotoxicity in the brains of mice administered 50 ppm MeHg in drinking water for 5 weeks.

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Background: Little is known about the role of atrial arrhythmias (AAs) in triggering Torsade de Pointes (TdP) in patients with long QT syndrome (LQTS). The aim of this study was to examine the contribution of AAs to the development of TdP in acquired LQTS patients.

Methods: The initiation patterns of 81 episodes of TdP obtained from 34 consecutive acute acquired LQTS patients (14 men, median age, 69 years; median QTc, 645.

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T-lineage acute lymphoblastic leukaemia (T-ALL) is a high-risk tumour that has eluded comprehensive genomic characterization, which is partly due to the high frequency of noncoding genomic alterations that result in oncogene deregulation. Here we report an integrated analysis of genome and transcriptome sequencing of tumour and remission samples from more than 1,300 uniformly treated children with T-ALL, coupled with epigenomic and single-cell analyses of malignant and normal T cell precursors. This approach identified 15 subtypes with distinct genomic drivers, gene expression patterns, developmental states and outcomes.

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DNA methylation is a crucial epigenetic modification that regulates gene expression and determines cell fate; however, the triggers that alter DNA methylation levels remain unclear. Recently, we showed that S-nitrosylation of DNA methyltransferase (DNMT) induces DNA hypomethylation and alters gene expression. Furthermore, we identified DBIC, a specific inhibitor of S-nitrosylation of DNMT3B, to suppress nitric oxide (NO)-induced gene alterations.

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Nitric oxide (NO) plays a physiological role in signal transduction and excess or chronic NO has toxic effects as an inflammatory mediator. NO reversibly forms protein S-nitrosylation and exerts toxicological functions related to disease progression. DNA methyltransferases, epigenome-related enzymes, are inhibited in enzymatic activity by S-nitrosylation.

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Osteogenesis imperfecta is characterized by frequent fractures, bone deformities, and other systemic symptoms. Severe osteogenesis imperfecta may progress to hydrocephalus; however, treatment strategies for this complication remain unclear. Here, we describe severe osteogenesis imperfecta in an infant with symptomatic hydrocephalus treated with ventriculosubgaleal shunt placement.

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Upregulation of nitric oxide (NO) production contributes to the pathogenesis of numerous diseases via S-nitrosylation, a post-translational modification of proteins. This process occurs due to the oxidative reaction between NO and a cysteine thiol group; however, the extent of this reaction remains unknown. S-Nitrosylation of PRMT1, a major asymmetric arginine methyltransferase of histones and numerous RNA metabolic proteins, was induced by NO donor treatment.

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Methylmercury (MeHg) is a well-known environmental neurotoxicant that causes severe brain disorders such as Minamata disease. Although some patients with Minamata disease develop olfactory dysfunction, the underlying pathomechanism is largely unknown. We examined the effects of MeHg on the olfactory system using a model of MeHg poisoning in which mice were administered 30 ppm MeHg in drinking water for 8 weeks.

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The link between changes in astrocyte function and the pathological progression of Alzheimer's disease (AD) has attracted considerable attention. Interestingly, activated astrocytes in AD show abnormalities in their lipid content and metabolism. In particular, the expression of apolipoprotein E (ApoE), a lipid transporter, is decreased.

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Reactive carbonyl species (RCS), which are abundant in the environment and are produced in vivo under stress, covalently bind to nucleophilic residues such as Cys in proteins. Disruption of protein function by RCS exposure is predicted to play a role in the development of various diseases such as cancer and metabolic disorders, but most studies on RCS have been limited to simple cytotoxicity validation, leaving their target proteins and resulting physiological changes unknown. In this study, we focused on methyl vinyl ketone (MVK), which is one of the main RCS found in cigarette smoke and exhaust gas.

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Article Synopsis
  • Aducanumab and lecanemab are FDA-approved antibodies aimed at treating Alzheimer's disease by targeting the toxic aggregates of the amyloid-β peptide in the brain.
  • Despite these advancements, the current effects of immunotherapy are limited, indicating the need to reassess the amyloid hypothesis that has guided Alzheimer's research.
  • The C99 fragment, a precursor to amyloid-β, accumulates in the brain and causes toxicity within neurons, suggesting it could be a significant therapeutic target alongside the amyloid hypothesis.
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DNA methyltransferases (DNMTs) catalyze methylation at the C5 position of cytosine with S-adenosyl-L-methionine. Methylation regulates gene expression, serving a variety of physiological and pathophysiological roles. The chemical mechanisms regulating DNMT enzymatic activity, however, are not fully elucidated.

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Alzheimer's disease (AD) is a progressive neurodegenerative brain disorder and the most common cause of dementia in the elderly. The presence of large numbers of senile plaques, neurofibrillary tangles, and cerebral atrophy is the characteristic feature of AD. Amyloid β peptide (Aβ), derived from the amyloid precursor protein (APP), is the main component of senile plaques.

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Methylmercury (MeHg), an environmental toxicant, induces neuronal cell death and injures specific areas of the brain. MeHg is known to induce oxidative and endoplasmic reticulum (ER) stress. The unfolded protein response (UPR) pathway has a dual nature in that it regulates and protects cells from an overload of improperly folded proteins in the ER, whereas excessively stressed cells are eliminated by apoptosis.

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Introduction: Data are limited regarding outcomes of cryoballoon ablation for atrial fibrillation (AF) in patients with heart failure (HF). This large-scale multicenter study aimed to evaluate the prognosis of patients with HF after cryoballoon ablation for AF.

Methods: Among 3655 patients undergoing cryoballoon ablation at 17 institutions, 549 patients (15%) (391 with paroxysmal AF and 158 with persistent AF) diagnosed with HF preoperatively were analyzed.

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Article Synopsis
  • Liquid biopsy is a noninvasive method using blood samples to detect genomic changes, offering an alternative to traditional tissue biopsies for patients with neuroblastoma (NB).
  • In this study, researchers analyzed cell-free DNA (cfDNA) from 24 NB patients at diagnosis, focusing on MYCN amplification and 11q loss of heterozygosity (11qLOH) using droplet digital PCR (ddPCR).
  • The analysis showed a strong correlation (0.88) between MYCN copy numbers in cfDNA and tumor DNA, indicating that cfDNA is a reliable source for assessing these genomic factors in NB patients.
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Background: The present study aimed to assess the appropriate oxygen saturation target in patients with pediatric respiratory diseases by lowering the oxygen saturation target from SpO 94% to 90%. No previous study has explored appropriate oxygen saturation targets in respiratory diseases other than bronchiolitis.

Methods: The present, prospective, single-arm intervention trial enrolled pediatric inpatients with bronchiolitis, bronchitis, pneumonia, and asthma.

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Endosomal anomalies because of vesicular traffic impairment have been indicated as an early pathology of Alzheimer'| disease (AD). However, the mechanisms and therapeutic targets remain unclear. We previously reported that βCTF, one of the pathogenic metabolites of APP, interacts with TMEM30A.

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