Publications by authors named "Makoto Ogasawara"

We demonstrate high-output-power and high-efficiency operation of 1.3-µm-wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). By introducing a metal reflector and adjusting the phase of the reflected light via optimization of the thickness of the p-InP cladding layer, we successfully achieve an output power of approximately 400 mW with the slope efficiency of 0.

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We demonstrate high-power continuous-wave (CW) lasing oscillation of 1.3-µm wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). Single-mode operation with an output power of over 100 mW, a side-mode suppression ratio (SMSR) of over 50 dB, and a narrow single-lobe beam with a divergence angle of below 1.

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Several studies have demonstrated increased pericardial effusion during anti-PD-1 immunotherapy, and treatment in patients who have developed pericardial tamponade is controversial. In this study, we describe a 63-year-old woman with stage IVA lung adenocarcinoma given pembrolizumab as a first-line therapy. After four cycles of pembrolizumab treatment, the patient suddenly developed a pericardial tamponade.

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Background: The role of necroptosis in myocardial injury has not been fully characterized. Here we examined roles of mitochondrial permeability transition pore (mPTP) and autophagy in necroptosis of cardiomyocytes.

Methods And Results: In H9c2 cells, necroptosis was induced by treatment with TNF-α (TNF) and z-VAD-fmk (zVAD) for 24h, and necroptotic death was determined by LDH release (as % of total).

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Chronic kidney disease (CKD) is known to increase myocardial infarct size after ischemia/reperfusion. However, a strategy to prevent the CKD-induced myocardial susceptibility to ischemia/reperfusion injury has not been developed. Here, we examined whether epoetin β pegol, a continuous erythropoietin receptor activator (CERA), normalizes myocardial susceptibility to ischemia/reperfusion injury by its effects on protective signaling and metabolomes in CKD.

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Background: Activity of mTOR complex 1 (mTORC1) has been shown to be up-regulated in animal models of heart failure. Here, we investigated the change and role of mTORC1 in human nonischemic dilated cardiomyopathy (NICM).

Methods: Endomyocardial biopsy specimens were obtained from patients with NICM (n=52) and from Brugada syndrome patients with normal LVEF as controls (n=10).

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A 65-year-old male developed acute myocardial infarction due to coronary artery dissection and tricuspid valve injury after blunt chest trauma. Acute myocardial infarction was treated by coronary artery intervention; however, refractory heart failure with pleural effusion remained. The first transthoracic echocardiography (TTE) on admission failed to clearly visualize the tricuspid valve and right ventricle due to poor image quality.

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Background: Type 2 diabetes mellitus (T2DM) worsens the outcome after myocardial infarction (MI). Here, we hypothesized that inhibition of dipeptidyl peptidase-4 (DPP-4) improves survival after MI in T2DM by modifying autophagy in the non-infarcted region of the heart.

Methods And Results: Under baseline conditions, there was no significant difference between levels of myocardial autophagy marker proteins in OLETF, a rat model of T2DM, and in LETO, a non-diabetic control.

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The purpose of this study was to evaluate the accuracy of commercially available software, using patient DVH-based QA metrics, by investigating the correlation between estimated 3D patient dose and magnitude of MLC misalignments. We tested 3DVH software with an ArcCHECK. Two different calculating modes of ArcCHECK Planned Dose Perturbation (ACPDP) were used: "Normal Sensitivity" and "High Sensitivity".

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Type 2 diabetes mellitus (T2DM) is often complicated with diastolic heart failure, which decompensates under increased afterload. Focusing on cardiac metabolomes, we examined mechanisms by which T2DM augments ventricular diastolic stiffness in response to pressure overloading. Pressure-volume relationships (PVRs) and myocardial metabolomes were determined at baseline and during elevation of aortic pressure by phenylephrine infusion in a model of T2DM, OLETF, and its non-diabetic control, LETO.

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Loss of mitochondrial membrane potential (ΔΨm) is known to be closely linked to cell death by various insults. However, whether acceleration of the ΔΨm recovery process prevents cell necrosis remains unclear. Here we examined the hypothesis that facilitated recovery of ΔΨm contributes to cytoprotection afforded by activation of the mitochondrial ATP-sensitive K+ (mKATP) channel or inactivation of glycogen synthase kinase-3β (GSK-3β).

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Glycogen synthase kinase-3β (GSK-3β) is a major positive regulator of the mitochondrial permeability transition pore (mPTP), a principle trigger of cell death, under the condition of oxidative stress. However, the mechanism by which cytosolic GSK-3β translocates to mitochondria, promoting mPTP opening, remains unclear. Here we addressed this issue by analyses of the effect of site-directed mutations in GSK-3β on mitochondrial translocation and protein/protein interactions upon oxidative stress.

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Background: Abnormal ventricular repolarization is a predictor of cardiovascular mortality. In this study, we tested the hypothesis that glycemic control reverses abnormal ventricular repolarization in patients with type 2 diabetes.

Methods: We analyzed longitudinal changes in repolarization indices of electrocardiograms in retrospectively enrolled 44 patients with type 2 diabetes and 44 age-matched healthy subjects.

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Background: A considerable number of patients with atrial fibrillation (AF) develop cardioembolic stroke (CE) despite low CHADS2 score. We examined the possibility that use of the atrial electromechanical interval (AEMI) improves prediction of CE in patients with paroxysmal AF (PAF), particularly those with low CHADS2 score.

Methods: We consecutively enrolled 108 patients with nonvalvular PAF and 52 healthy subjects as controls.

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Background: The combination of adenosine infusion with low-level exercise has become a common approach for inducing stress during stress myocardial perfusion imaging (MPI). We investigated stress MPI performed by combined low-level exercise and adenosine infusion. This combined protocol can decrease adverse reactions and reduce the effect of scattered rays from the liver.

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For children, cardiac nuclear medicine imaging has not been widely used because of problems of physical motion, even in schoolchildren who require no sedation. In this study, rest-stress myocardial perfusion imaging (MPI) with technetium-99m-tetrofosmin (Tc-99m TF) was performed with the use of a Vac-Loc cushion, a patient immobilizer commonly used for radiotherapy, for immobilizing school-age patients. The immobilizer attenuated the gamma radiation by 6%.

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Objective The present study aimed at establishing a new protocol using both (99m)Tc-Tetrofosmin (TF) and (123)I-BMIPP SPECT to detect myocardial damage within one hour. Methods Initial (123)I-BMIPP SPECT was immediately followed by (99m)Tc-TF SPECT. The influence of (123)I scattered rays on (99m)Tc energy windows set at 15% and 10% were measured using an RH-2 phantom.

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We have developed a new protocol of myocardial perfusion-gated single-photon emission computed tomography (SPECT), by use of technetium-99m sestamibi (MIBI), in which SPECT imaging at rest followed by SPECT imaging after adenosine with low level ergometer stress can be conducted by use of the Monzen position within a shortened total testing time of 1 h or less. The study group consisted of 137 patients who underwent this new imaging protocol. The diagnostic quality of the images was as good as that of images obtained with the conventional method (30-60 min after the injection of MIBI).

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We have devised a new position (Monzen position) which can suppress the influence of scattered rays from surrounding organs (liver, etc.) when conducting myocardial imaging. Unlike the conventional techniques, which require a waiting period of 30-60 minutes before imaging can be started after the infusion of technetium-99m sestamibi or technetium-99m tetrofosmin, this position allows single-photon emission tomography to be started about 5-10 minutes after the infusion of the tracer.

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We had 126 patients with inner ear malformation diagnosed with temporal bone computed tomography (CT) scans at Azabu Triology Hospital between 1996 and 2002. We classified cases of inner ear malformation according to Jackler et al. The incidence of inner ear malformation in our series was as follows; 1.

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