Publications by authors named "Ichimiya H"

Introduction: The underlying risks of asymptomatic embolization during high-power short-duration (HPSD) ablation for atrial fibrillation remain unclear. We aimed to evaluate microembolic signals (MESs) during HPSD ablation with power settings of 50 and 90 W in comparison with those during cryoballoon (CB) ablation using a novel carotid ultrasound-Doppler system that classifies solid and air bubble signals using real-time monitoring.

Methods And Results: Forty-seven patients underwent HPSD ablation using radiofrequency (RF), and 13 underwent CB ablation.

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Background: Most studies on pitch shift provoked by hearing loss have been conducted using pure tones. However, many sounds encountered in everyday life are harmonic complex tones. In the present study, psychoacoustic experiments using complex tones were performed on healthy participants, and the possible mechanisms that cause pitch shift due to hearing loss are discussed.

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The concept of complex and high-risk indicated procedures using percutaneous coronary intervention (CHIP-PCI) has recently been defined. However, few studies have investigated the prognosis of patients after CHIP-PCI. We enrolled 322 consecutive patients who underwent CHIP-PCI.

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Deutsch's scale illusion demonstrates that the overall pitch range is the preferred organization when in competition with both local (note-to-note) pitch proximity and laterality (differences in the input ear). Such intricate factors can make it difficult to mimic this illusion. If a note is under a condition in which grouping by the overall pitch range and the local pitch proximity do not conflict, we hypothesized that an illusion would be perceived simply as the result of the competition between pitch proximity and laterality.

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Purpose: A diagnostic and treatment strategy for appendiceal tumors (ATs) has not been established. We aimed to evaluate our treatment strategy in ATs, including laparoscopic surgery (LS), and to identify preoperative malignancy predictors.

Methods: A total of 51 patients between 2011 and 2021 were retrospectively reviewed.

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Article Synopsis
  • The study evaluated ice formation on the surfaces of two types of cryoballoons during cryoablation, specifically a standard cryoballoon (SCB) and a novel cryoballoon (NCB).
  • Ice formation was found to be significantly greater on the lower side of the cryoballoons compared to the upper side, with the NCB showing a visibly larger area of ice formation.
  • These findings suggest that the increased ice formation on the lower side and proximal hemisphere could enhance ablation effectiveness on the left atrial posterior wall during cryoballoon procedures.
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We report here the case of a 92-year-old woman with atrial fibrillation bradycardia in which leadless pacemaker implantation was performed with a difficult delivery of the catheter sheath due to an extremely large right atrium. Using a snare technique with correction of the direction of the force on the catheter toward the right ventricle (RV) can result in successful delivery of the pacemaker catheter and stable placement of the pacemaker system in the RV septum. This specific snare technique has the potential to facilitate leadless pacemaker implantation safely in a severely dilated chamber of the heart, making this technique effective to use in clinical practice.

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Objective The left atrial appendage (LAA) is one of the major sources of cardiac thrombus formation. Three-dimensional transesophageal echocardiography (TEE) made it possible to perform a detailed evaluation of the LAA morphologies. This study aimed to evaluate the clinical implications of the LAA orifice area.

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Article Synopsis
  • Graphene nanoribbons (GNRs) are highly promising for electronic devices due to their excellent carrier mobility and ultra-thin nature, yet large-scale production remains challenging.
  • * The study introduces a method to create a large-scale GNR network using vanadium pentoxide (VO) nanowires assembled on graphene through electrostatic interactions and polymer layers.
  • * After etching away the nanowires, a stable GNR network structure is formed, demonstrating semiconductor properties, paving the way for future applications in electronics and physics.*
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In cryoballoon ablation (CBA), a contrast medium is commonly used to confirm balloon occlusion of the pulmonary veins (PVs). However, a contrast medium cannot always be used in patients with renal dysfunction and allergy. The present study aimed to assess the efficacy and safety of CBA without the use of a contrast medium.

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Introduction: With regard to short-term outcome in atrial fibrillation (AF), the benefit of cryoballoon ablation (CBA) by pressing a balloon against the earliest pulmonary vein (PV) potential site during PV isolation (earliest potential [EP]-guided CBA) has been previously demonstrated. The present study aimed to evaluate the long-term outcome of the EP-guided CBA.

Methods And Results: This study included 136 patients from two randomized studies, who underwent CBA for paroxysmal AF for the first time.

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Electrophysiological studies have rarely evaluated the sites prone to pulmonary vein (PV) conduction gap during cryoballoon ablation (CBA) for atrial fibrillation (AF). In addition, no studies have analyzed the sequence of PV potentials just before PV isolation during CBA for AF. Of the 238 patients who underwent first-time CBA for paroxysmal AF, 115 PVs of 29 patients who underwent repeat session due to recurrence after the procedure were retrospectively evaluated in the study.

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The Clinical Frailty Scale (CFS) is a simple tool to assess patients' frailty and may help to predict adverse outcomes in elderly patients. The aim of the present study was to examine the impact of CFS on clinical outcomes and bleeding events after successful percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI). We enrolled 266 consecutive patients with STEMI who underwent primary PCI in between January 2015 and June 2018.

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Low skeletal muscle mass is one of the components of sarcopenia. However, the prognostic impact of skeletal muscle mass on clinical outcomes in patients after transcatheter aortic valve replacement (TAVR) remains unclear. Therefore, we assessed the impact of skeletal muscle mass on future cardiovascular events in patients undergoing TAVR.

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Mechanical small bowel obstruction (SBO) is a common postoperative complication, and most cases are caused by postoperative adhesions. We herein report a case of SBO with superior mesenteric vein occlusion caused by a metal staple after laparoscopic appendectomy. A 35-year-old Japanese woman presented to our department with severe upper abdominal pain and vomiting.

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Transition metal dichalcogenides (TMDCs) have received attention as atomically thin post-silicon semiconducting materials. Tuning the carrier concentrations of the TMDCs is important, but their thin structure requires a non-destructive modulation method. Recently, a surface-charge transfer doping method was developed based on contacting molecules on TMDCs, and the method succeeded in achieving a large modulation of the electronic structures.

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No studies have evaluated both the time-to-isolation (TTI) and the sequence of pulmonary vein (PV) potentials in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study aimed to prospectively evaluate the acute results of pulmonary vein isolation (PVI) using a novel CBA technique-the earliest potential (EP) of PV-guided CBA-in paroxysmal AF. We pressed a balloon against the earliest PV potential site during PVI when TTI could not be achieved within 60 s (EP-guided CBA group).

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Article Synopsis
  • - Modulating the electronic structure of transition metal dichalcogenides (TMDCs) is essential for enhancing the functionality of electronic and optical devices, particularly through localized changes in carrier concentration.
  • - A new method is introduced, utilizing spontaneous pattern formation in a molecular film when exposed to water, achieving localized carrier doping on a nanoscale of approximately 100 nm in TMDCs.
  • - The research highlights that the dynamics of pattern formation and molecular flow rate vary with TMDC thickness, enabling the creation of intricate electronic junctions essential for advancing optoelectronic technologies.
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To clarify the possible mechanism causing binaural diplacusis with low-tone hearing loss, two psychoacoustic experiments were performed with 20 healthy subjects, using harmonic complex tones. In the first experiment, two tones were presented unilaterally, either from the right or left side. One of the tones presented was higher in frequency in terms of the fundamental component, but lower or equal in frequency in terms of the highest component, than the other tone.

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Spontaneous pattern formation is an energetically favorable process and is shown in nature in molecular-scale assembly, biological association, and soft material organizations. The opposite regime, the artificial process, which is widely applied to the fabrication of semiconducting devices, such as lithographic techniques, requires enormous amounts of energy. Here, we propose a concept of tuning the properties of semiconducting MoS and WSe devices using the spontaneous pattern formation of adjacent molecular films.

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Persistent mesocolon is an embryological anomaly of the colon resulting from failure of the primitive dorsal mesocolon to fuse with the parietal peritoneum. We herein present a case of laparoscopic high anterior resection for triple colorectal cancers with persistent ascending and descending mesocolons and a right-bound inferior mesenteric artery. Preoperative 3-D CT demonstrated that the sigmoid colon had shifted to the right abdomen and was located under the ascending colon.

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Although drug-eluting stents (DESs) reduce the rates of in-stent restenosis (ISR) and subsequent target lesion revascularization, stent fracture (SF) after DES implantation has become an important concern because of its potential association with restenosis and stent thrombosis. We aimed to assess the pathogenic impact of SF on in-stent restenotic neointimal tissue components after DES implantation. We analyzed 43 consecutive patients (14 with SF and 29 without SF) with ISR requiring revascularization after DES implantation between January 2008 and March 2014.

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We previously reported that molecular hydrogen (H) acts as a novel antioxidant to exhibit multiple functions. Moreover, long-term drinking of H-water (water infused with H) enhanced energy expenditure to improve obesity and diabetes in / mice accompanied by the increased expression of fibroblast growth factor 21 (FGF21) by an unknown mechanism. H was ingested by drinking of H-water or by oral administration of an H-producing material, MgH.

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We previously showed that H2 acts as a novel antioxidant to protect cells against oxidative stress. Subsequently, numerous studies have indicated the potential applications of H2 in therapeutic and preventive medicine. Moreover, H2 regulates various signal transduction pathways and the expression of many genes.

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