Publications by authors named "Atsushi Yamamoto"

A 49-year-old female was admitted to our hospital due to acute-onset dysarthria and unstable gait. Brain MR diffusion weighted imaging revealed high signal intensities in the midbrain. Brain tumors, abscess and demyelinating lesions was suspected firstly as etiology of the lesion and antibiotics and antiviral drug were started under consulting with the neurosurgeon about brain biopsy.

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This study investigates the mass spectrometric analysis of 10 novel amidoamine oxide compounds, which are innovative hydrogelators for polar solvents. This research aims to identify characteristic fragment patterns for these amide compounds using high-resolution mass spectrometry. Methanol solutions of the compounds were analyzed in positive and negative ion modes, and MS1 and MS2 spectra at 6 collision energy levels were obtained via electrospray ionization and hybrid tandem mass spectrometry.

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Postoperative pancreatic fistula (POPF) remains a major and serious problem after pancreaticoduodenectomy (PD). In its presence, pancreatic juice may leak from the main duct or branches of the pancreatic stump. To prevent this, we have applied a newly modified anastomosis of pancreaticogastrostomy (PG) using a linear stapler (stapled PG).

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The capture and electrochemical conversion of dilute CO in air is a promising approach to mitigate global warming. Aiming to increase the efficiency of the electrochemical reduction of CO, we fabricated electrodes and developed a custom-designed sealed electrochemical reaction system to study the mechanism of this conversion. The performance of three metal electrodes, Ag, Cu, and SUS 316 L, was compared in an aprotic ionic liquid as the electrolyte to monitor the CO concentration and chemical reactions using a CO sensor and diffuse reflectance infrared Fourier transform spectroscopy and Raman spectroscopy in CO/N (400 ppm CO and 99.

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Aim: The unique feature of Fontan circulation is elevated central venous pressure, which causes Fontan-associated liver disease (FALD). FALD is associated with a high incidence of hepatocellular carcinoma (HCC). Performing biopsies in patients with FALD is difficult as a result of warfarinization; gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI), a noninvasive examination, is useful for characterizing liver disease and detecting HCC.

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Background: A rotator cuff retear following arthroscopic rotator cuff repair (ARCR) is a concern in older patients. However, only a few of its risk factors are amenable to preoperative intervention. We aimed to elucidate the relationship between preoperative nutritional status and rotator cuff retears after ARCR.

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Background: This study evaluated right ventricular (RV) volume, strain, and morphology using cardiac 4-dimensional computed tomography (4D-CT) to detect pulmonary hypertension (PH) in adults with repaired tetralogy of Fallot (TOF) scheduled for transcatheter pulmonary valve implantation (TPVI).

Methods And Results: Using cardiac 4D-CT data, we calculated RV strain in 3 different geometries and RV outflow tract (RVOT) mass in 42 patients with repaired TOF. We compared RV strain and RVOT mass between patients with and without PH.

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Objectives: On F-Fludeoxyglucose (FDG) PET/CT, active sarcoid lesions are often difficult to differentiate from malignant lesions. We investigated the potential of the glucose metabolic rate (MR, mg/min/100 mL), a new quantification of glucose metabolic kinetics derived from direct reconstruction based on linear Patlak analysis, to distinguish between sarcoidosis and malignant lesions.

Materials And Methods: A total of 100 patients with cardiac sarcoidosis (CS) and 67 patients with cancer who underwent four-dimensional FDG PET/CT were enrolled.

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Although handheld ultrasound devices (HUDs) are commonplace, their ability to diagnose fecal retention (FR) remains unclear. This prospective observational study examined HUDs' usefulness in diagnosing FR in patients with constipation in a palliative care setting. Between 10 December 2020 and 30 June 2022, we compared rectal ultrasonographic findings obtained using HUDs with clinical manifestations in 64 males and 70 females (48%, 52%, 68 ± 11 years old) with constipation who had undergone computed tomography (CT).

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Rationale And Objectives: This study investigated the use of deep learning-generated virtual positron emission tomography (PET)-like gated single-photon emission tomography (SPECT) for assessing myocardial strain, overcoming limitations of conventional SPECT.

Materials And Methods: SPECT-to-PET translation models for short-axis, horizontal, and vertical long-axis planes were trained using image pairs from the same patients in stress (720 image pairs from 18 patients) and resting states (920 image pairs from 23 patients). Patients without ejection-fraction changes during SPECT and PET were selected for training.

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Nanostructured lead telluride PbTe is among the best-performing thermoelectric materials, for both p- and n-types, for intermediate temperature applications. However, the fabrication of power-generating modules based on nanostructured PbTe still faces challenges related to the stability of the materials, especially nanoprecipitates, and the bonding of electric contacts. In this study, in situ high-temperature transmission electron microscopy observation confirmed the stability of nanoprecipitates in p-type PbNaGeTe up to at least ∼786 K.

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The prevalence of chronic kidney disease (CKD) is increasing owing to the elderly population. Here, we investigated the effects of heat-treated (FK-23) and lysozyme-treated FK-23 (LFK) on the progression of CKD in rats. A CKD model was established using male Wistar rats by subjecting them to right nephrectomy (1K), followed by ischemia and reperfusion (IR).

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Background: Despite partial nephrectomy (PN) renal function preservation benefits, postoperative renal dysfunction may occur. Perirenal fat thickness (PFT) is associated with renal dysfunction such as diabetes; however, its role in renal tumour surgery is unclear. This study investigates the role of PFT in renal function after robot-assisted partial nephrectomy (RAPN).

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Background: Heart transplantation (HTx) is a definitive therapy for refractory heart failure. Cardiac allograft vasculopathy (CAV), characterized by diffuse arteriopathy involving the epicardial coronary arteries and microvasculature, is the major cause of death for patients with HTx. N-ammonia positron emission tomography (NH-PET) can offer diagnostic and prognostic utility for CAV.

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Classical swine fever (CSF) re-emerged in Japan in 2018 for the first time in 26 years. The disease has been known to be caused by a moderately pathogenic virus, rather than the highly pathogenic virus that had occurred in the past. However, the underlying pathophysiology remains unknown.

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Background/aim: Sorafenib and lenvatinib have long been used as a first-line treatment for advanced hepatocellular carcinoma (HCC). Along with the development of systemic chemotherapy for HCC, the concept of conversion hepatectomy has recently become widespread. The present study aimed to assess the clinical outcomes of sorafenib and lenvatinib for HCC regarding the possibility of conversion hepatectomy in clinical practice.

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Background: Surgical procedures are required to achieve long-term pretarsal roll fullness of the lower eyelids with a satisfactory appearance.

Objectives: To assess the efficacy of a surgical method using fat grafts for pretarsal augmentation of the lower eyelids.

Methods: We conducted a retrospective clinical study that included 12 Japanese patients (24 lower eyelids) who underwent pretarsal augmentation of the lower eyelids using fat grafts and were followed up for more than 6 months.

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Purpose To investigate whether right ventricular (RV) myocardial strain ratio (RVMSR) assessed using nitrogen 13 ammonia (N-NH) PET can predict cardiovascular events in patients with ischemic heart disease (IHD). Materials and Methods This retrospective study included 480 consecutive patients (mean age, 66 years ± 12 [SD]; 334 males and 146 females) with IHD who underwent N-NH PET. RVMSR was defined as the ratio of RV strain during stress to that at rest.

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Immune checkpoint inhibitor (ICI)-induced liver injury (LI) is a common adverse event, but the clinical characteristics based on the classification of hepatocellular injury and cholestatic types are not fully evaluated. This study aims to analyze risk factors and histological findings in relation to the classification of ICI-induced LI. In total, 254 ICI-induced LI patients among 1086 treated with ICIs between September 2014 and March 2022 were classified according to the diagnostic criteria for drug-induced LI (DILI), and their risk factors and outcomes were evaluated.

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Objective: To clarify the relationships between C-methionine (MET) positron emission tomography (PET) metrics and the histology, genetics, and prognosis of adult-type diffuse glioma (ADG) based on the World Health Organization (WHO) 2021 classification.

Methods: A total of 125 newly diagnosed patients with ADG were enrolled. We compared the maximum standardized uptake value (SUVmax), tumor-to-normal background ratio (TNR), metabolic tumor volume (MTV), and total lesion methionine uptake (TLMU) to the histology and genetics of the patients with ADG.

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Background: Multiparametric MRI (mpMRI) is widely used for the diagnosis, surveillance, and staging of prostate cancer. However, it has several limitations, including higher costs, longer examination times, and the use of gadolinium-based contrast agents. This study aimed to investigate the accuracy of preoperatively assessed index tumors (ITs) using biparametric MRI (bpMRI)/transrectal ultrasound (TRUS) fusion biopsy compared with radical prostatectomy (RP) specimens.

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Reversed-phase high performance liquid chromatography (RP-HPLC) is the most widely used chromatographic method. In addition to hydrophobic interactions, additional interactions such as electrostatic interactions may participate in the retention behaviour of an analyte. This makes it possible to use RP-HPLC for many types of analyte.

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Objective: The purpose of this retrospective study was to evaluate the relationship between bone mineral density (BMD), as assessed with dual-energy x-ray absorptiometry (DEXA), and Hounsfield units (HU) measured in volumes of interest (VOIs) and regions of interest (ROIs) on lumbar spine CT.

Methods: A retrospective analysis was performed on data of lumbar vertebrae obtained from patients who underwent both DEXA and lumbar spine CT scan within a 6-month period. Vertebrae with a history of compression fracture, infectious spondylitis, cement reinforcement, or lumbar surgery were excluded.

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In thermoelectric and other inorganic materials research, the significance of half-Heusler (HH) compositions following the 18-electron rule has drawn interest in developing and exploiting the potential of intermetallic compounds. For the fabrication of thermoelectric modules, in addition to high-performance materials, having both p- and n-type materials with compatible thermal expansion coefficients is a prerequisite for module development. In this work, the p-type to n-type transition of valence balanced/unbalanced HH composition of MgVNiSb was demonstrated by changing the Mg:V chemical ratio.

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Objective: To investigate the potential of whole-body digital C-methionine (MET) PET/CT imaging for simultaneous evaluation of thoracic cancer patients suspected of local recurrence (LR) after stereotactic radiosurgery (SRS) for brain metastasis.

Methods: A total of 45 lung or breast cancer patients suspected of LR after SRS were investigated using brain and whole-body MET-PET/CT scans. We compared the tumor-to-normal ratio (TNR) and maximum standardized uptake values (SUVmax) between patients with LR and radiation necrosis (RN) and performed receiver operating characteristic (ROC) analyses.

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