Publications by authors named "Kameyama T"

Luminescence color tuning of less toxic I-III-VI-based quantum dots (QDs) has been intensively investigated for application in wide-color-gamut displays. However, the emission peaks of these multinary QDs are relatively broad in the blue-light region compared to those in the green and red regions. Here, we report the synthesis of AgGaS (AGS) QDs that show a narrow blue emission peak through nonstoichiometry control and surface defect engineering.

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Background: Palbociclib is a cell-cycle targeted small molecule agent used as one of the standards of care in combination with endocrine therapy for patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Although several gene alterations such as loss of Rb gene and amplification of p16 gene are known to be conventional resistance mechanisms to cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors, the comprehensive landscape of resistance is not yet fully elucidated. The purpose of this study is to identify the novel resistant genes to the CDK4/6 inhibitors in HR-positive HER2-negative breast cancer.

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We report a case of numb chin syndrome caused by a small cortical infarction in the postcentral gyrus. A 67-year-old man suddenly developed numbness in his right lower lip and the chin. There were no apparent abnormal neurological symptoms other than numbness.

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Background: Blood pressure variability has been found to be a predictor of a stroke, heart failure, and ischemic heart disease that is independent of blood pressure control. This study used the variability independent of the mean (VIM) to evaluate the visit-to-visit blood pressure variability in patients previously undergoing catheter ablation (CA) of paroxysmal atrial fibrillation (PAF), and its relationship with AF recurrence was examined.

Method And Results: The subjects were 274 consecutive PAF patients who underwent CA at our hospital.

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Currently, four kinds of phosphorodiamidate morpholino oligomers (PMOs), such as viltolarsen, have been approved for the treatment of Duchenne muscular dystrophy (DMD); however, it is unclear whether human efficacy can be estimated using plasma concentrations. This study summarizes the tissue distribution of viltolarsen in mice and cynomolgus monkeys and evaluates the relationship between exposure and efficacy based on exon skipping. In the tissue distribution studies, all muscles in DMD-model mice showed higher concentrations of viltolarsen than those in wild-type mice and cynomolgus monkeys, and the concentrations in skeletal muscle were correlated with the exon-skipping efficiency in mice and cynomolgus monkeys.

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A red-light-activated phthalocyanine ruthenium complex has been designed as a catalyst for the bifunctionalization of styrene derivatives. The combination of a trifluoromethylation agent resistant to nucleophiles and various nucleophiles facilitates the concurrent incorporation of a trifluoromethyl group and various functional groups onto the double bond of the substrate. This reaction demonstrates the utility of mild, low-energy, and highly transmissive long-wavelength light for intricate molecular transformations in a one-pot procedure.

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Chronic thromboembolic pulmonary hypertension (CTEPH) is a chronic disease that can rapidly deteriorate into circulatory collapse when complicated by comorbidities. We herein describe a case involving a 43-year-old woman with class III obesity (body mass index of 63 kg/m) and severe CTEPH associated with total occlusion of the left main pulmonary artery who subsequently developed circulatory collapse along with multiple comorbidities, including acute kidney injury, pulmonary tuberculosis, and catastrophic antiphospholipid syndrome. The patient was successfully treated with two sessions of rescue balloon pulmonary angioplasty with veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support under local anesthesia without sedation, at cannulation and during the V-A ECMO run, to avoid invasive mechanical ventilation.

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Photosensitization of semiconductors by excitation of chiral plasmonic metallic nanostructures has attracted much attention, not only for the analysis and detection of circularly polarized light but also for its potential applications in chiral photosynthesis. Although there have been reports on the detection of semiconductor-sensitized current in chiral nanostructures precisely fabricated by physical vapor deposition and/or lithography techniques, there have been no studies using plasmonic metal nanocolloids synthesized by chemical processes. In this study, we report the establishment of a fabrication method for large-area chiral photoelectrodes and the semiconductor photosensitization phenomenon realized using chiral plasmonic nanoparticles.

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I-III-VI-based semiconductor quantum dots (QDs) have been intensively explored because of their unique controllable optoelectronic properties. Here we report one-pot synthesis of Na-doped Ag-In-Ga-S (AIGS) QDs incorporated in a GaO matrix. The obtained QDs showed a sharp band-edge photoluminescence peak at 557 nm without a broad-defect site emission.

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Astrocytes interact with not only synapses but also brain blood vessels through perivascular astrocyte endfeet (PV-AEF) to form the neurovascular unit (NVU). However, PV-AEF components have not been fully identified. Here, we biochemically isolated blood vessels from mouse brain homogenates and purified PV-AEF.

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Acute myocardial infarction (AMI) can rarely arise from non-lipid-rich coronary plaques. This study sought to compare the clinical outcomes after percutaneous coronary intervention (PCI) between AMI showing maximum lipid-core burden index in 4 mm (maxLCBI) < 400 and ≥ 400 in the infarct-related lesions assessed by near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). We investigated 426 AMI patients who underwent NIRS-IVUS in the infarct-related lesions before PCI.

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Narrowing the emission peak width and adjusting the peak position play a key role in the chromaticity and color accuracy of display devices with the use of quantum dot light-emitting diodes (QD-LEDs). In this study, we developed multinary Cu-In-Ga-S (CIGS) QDs showing a narrow photoluminescence (PL) peak by controlling the Cu fraction, i.e.

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Quantum dots (QDs), which have high color purity, are expected to be applied as emitting materials to wide-color-gamut displays. To enable their use as an alternative to Cd-based QDs, it is necessary to improve the properties of QDs composed of low-toxicity materials. Although multielement QDs such as Ag-In-Ga-S are prone to spectrally broad emission from defect sites, a core/shell structure covered with a GaS shell is expected to enable sharp emission from band-edge transitions.

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Ramified, polarized protoplasmic astrocytes interact with synapses via perisynaptic astrocyte processes (PAPs) to form tripartite synapses. These astrocyte-synapse interactions mutually regulate their structures and functions. However, molecular mechanisms for tripartite synapse formation remain elusive.

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Balloon pulmonary angioplasty (BPA) has been reported to be effective and safe to an acceptable level in patients with distal-type, inoperable chronic thromboembolic pulmonary hypertension (CTEPH), resulting in improved long-term survival. However, evidenced treatment options and strategy including medical therapy of antithrombotic therapy, glucocorticoids, immunosuppressants, and pulmonary hypertension (PH)-specific therapies are scarce in patients with significant PH and right heart failure associated with Takayasu arteritis and peripheral pulmonary artery stenosis, both of which mimic CTEPH. Moreover, there has been still concern on safety and lack of established methodology in performing BPA for these conditions.

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The hypothalamus is comprised of heterogenous cell populations and includes highly complex neural circuits that regulate the autonomic nerve system. Its dysfunction therefore results in severe endocrine disorders. Although recent experiments have been conducted for in vitro organogenesis of hypothalamic neurons from embryonic stem (ES) or induced pluripotent stem (iPS) cells, whether these stem cell-derived hypothalamic neurons can be useful for regenerative medicine remains unclear.

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AuRh bimetallic alloy nanoparticles (NPs) were successfully prepared by simultaneous sputtering of Au and Rh in a room-temperature ionic liquid (RTIL) of ,-diethyl--methyl--(2-methoxyethyl) ammonium tetrafluoroborate (DEME-BF). Bimetallic AuRh alloy NPs of 1-2 nm in size were formed in the RTIL. The alloy composition was controllable by changing the surface areas of Au and Rh plates used as sputtering targets.

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Human stem cell-derived organoid culture enables the analysis of the cellular function in three-dimensional aggregates mimicking native organs, and also provides a valuable source of specific cell types in the human body. We previously established organoid models of the hypothalamic-pituitary (HP) complex using human pluripotent stem cells. Although the models are suitable for investigating developmental and functional HP interactions, we consider that isolated pituitary cells are also useful for basic and translational research on the pituitary gland, such as stem cell biology and regenerative medicine.

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Chemodynamic therapy (CDT), which consumes endogenous hydrogen peroxide (HO) to generate reactive oxygen species (ROS) and causes oxidative damage to tumor cells, shows tremendous promise for advanced cancer treatment. However, the rate of ROS generation based on the Fenton reaction is prone to being restricted by inadequate HO and unattainable acidity in the hypoxic tumor microenvironment. We herein report a multifunctional nanoprobe (BCGCR) integrating bimodal imaging and photothermal-enhanced CDT of the targeted tumor, which is produced by covalent conjugation of bovine serum albumin-stabilized CuS/GdO nanoparticles (NPs) with the Cy5.

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Multicarrier dynamics in heterostructured ZnS-AgInS (ZAIS) dumbbell-like nanoparticle (nanodumbell), which consists of two visible-light absorptive domains (ellipsoidal tip domains) directly linked to each end of a 22 nm length rod domain of the ZAIS nanodumbell with a quasi-type-II heterostructure, was investigated by femtosecond transient absorption spectroscopy under variable excitation intensities. Quantitative analysis together with the numerical simulations for the excitation intensity dependence of the dynamics revealed that only one electron-hole pair survived in the overall dumbbell as a consequence of Auger recombination, even though multiple carriers were formed on both terminal tip domains. This result strongly suggested carrier-carrier interaction between the tip domains, leading to the long-range Auger recombination via tunneling across a rod potential barrier.

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Hypothalamic melanin-concentrating hormone (MCH) neurons are important regulators of multiple physiological processes, such as sleep, feeding, and memory. Despite the increasing interest in their neuronal functions, the molecular mechanism underlying MCH neuron development remains poorly understood. We report that a three-dimensional culture of mouse embryonic stem cells (mESCs) can generate hypothalamic-like tissues containing MCH-positive neurons, which reproduce morphologic maturation, neuronal connectivity, and neuropeptide/neurotransmitter phenotype of native MCH neurons.

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Multilayered proliferation in an adherent culture as well as proliferation in a suspension culture is a characteristic feature of cancer cells. We previously showed using T47D human mammary cancer cells that nectin-4, upregulated in many cancer cells, cis-interacts with ErbB2 and its trastuzumab-resistant splice variants, p95-ErbB2 and ErbB2ΔEx16, and enhances DNA synthesis mainly through the PI3K-AKT pathway in an adherent culture. We showed here that only the combination of nectin-4 and p95-ErbB2, but not that of nectin-4 and ErbB2 or that of nectin-4 and ErbB2ΔEx16, cooperatively enhanced multilayered T47D cell proliferation through the Hippo pathway-mediated SOX2 gene expression in an adherent culture.

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Tumor viruses gain control of cellular functions when they infect and transform host cells. Alternative splicing is one of the cellular processes exploited by tumor viruses to benefit viral replication and support oncogenesis. Epstein-Barr virus (EBV) participates in a number of cancers, as reported mostly in nasopharyngeal carcinoma (NPC) and Burkitt lymphoma (BL).

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Background: The association between right ventricular function and exercise capacity in patients with chronic heart failure remains uncertain. Several studies very recently mentioned the association between right ventricular reserve and exercise capacity, whereas the implication of tricuspid annular plane systolic excursion (TAPSE) remains uninvestigated. We aimed to assess the impact of TAPSE on exercise capacity in cardiac rehabilitation candidates.

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