Publications by authors named "Hamaguchi H"

Although multiple magnetic resonance imaging (MRI) indices are known to be sensitive to the noninvasive assessment of myelin integrity, their relative sensitivities have not been directly compared. This study aimed to identify the most sensitive MRI index for characterizing myelin composition in the spinal cord's gray matter (GM) and white matter (WM). MRI was performed on a deer's ex vivo cervical spinal cord.

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This study aimed to examine the effect of simulation training using a three-dimensional (3D)-printed patient-specific vascular model on the advanced vascular catheterization skills of experienced interventional radiologists (IRs). Two specific anatomic types of 3D-printed patient-specific models from two patients with challenging celiac axis arterial anatomy were constructed. The Global Rating Scale of Endovascular Performance (GRS-EP) was used to evaluate vascular insertion skills.

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Carotid artery stenting (CAS) has traditionally been performed using the transfemoral approach (TFA). Recently, the transradial approach (TRA) has gained attention for its lower invasiveness and reduced complication risk. This study compares outcomes between two access strategy timeframes, TFA-first and TRA-first, to evaluate how this shift influences outcomes in a real-world setting.

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Purpose: The ratio of the internal carotid artery (ICA) to the common carotid artery (CCA), especially the "AcT ratio," which is a modified measurement method of acceleration time, is useful for diagnosing ICA-origin stenosis. However, previous studies were single-center studies. Therefore, this multicenter, retrospective, cross-sectional study aimed to determine whether a method using the AcT ratio is useful for estimating stenosis rates.

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Article Synopsis
  • The study focused on understanding the genetic basis of early-onset ALS, a severe neurodegenerative disease, by analyzing families with members diagnosed before the age of 40.
  • Research methods included whole-exome sequencing and biochemical assessments, leading to the identification of gene variants in SPTLC2 that are linked to elevated sphingolipid production in early-onset ALS patients.
  • Findings suggest a connection between specific genetic mutations and disrupted sphingolipid metabolism, contributing to ALS development and highlighting the genetic complexity of the disease.
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Whether diurnal variation exists in quantitative MRI indices such as the T1rho relaxation time (T1ρ) of the intervertebral disc (IVD) is yet to be explored. This prospective study aimed to evaluate the diurnal variation in T1ρ, apparent diffusion coefficient (ADC), and electrical conductivity (σ) of lumbar IVD and its relationship with other MRI or clinical indices. Lumbar spine MRI, including T1ρ imaging, diffusion-weighted imaging (DWI), and electric properties tomography (EPT), was conducted on 17 sedentary workers twice (morning and evening) on the same day.

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Hydrophobic nanoparticles (NPs) in water were considered unstable because they lack the repulsive electrostatic interaction and steric effect to prevent aggregation. In this study, porous hydrophobic NPs of two star-shaped giant molecules, , were found to be stable in water and able to retain their kinetic stability in a wide range of temperatures, pH values, and ionic strengths. Unlike the solid hydrophobic NPs that aggregate even with the negative zeta potential (ζ) induced by surface-structured hydrogen-bonded (SHB) water, the porous morphology of NPs reduces the entropically driven hydrophobic effect to prevent aggregation.

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Article Synopsis
  • - A vascular intervention simulation model was developed using a 3D-printed transparent flexible resin, which was then compared to porcine arteries in terms of mechanical properties like elastic modulus and friction.
  • - The study found that the resin was significantly stiffer than porcine arteries, and as the resin cured longer, its transparency and adhesive strength decreased, while porcine arteries maintained lower adhesive strength overall.
  • - Coating the resin with silicone made its surface friction comparable to that of porcine arteries, indicating that this resin could be effectively used for realistic vascular models in simulations.
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Myokines, secreted factors from skeletal muscle, act locally on muscle cells or satellite cells, which is important in regulating muscle mass and function. Here, we found platelet-derived growth factor subunit B (PDGF-B) is constitutively secreted from muscle cells without muscle contraction. Furthermore, PDGF-B secretion increased with myoblast to myotube differentiation.

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Carotid artery ultrasonography is capable of diagnosing or inferring the presence or absence of stenosis or occlusion of the internal carotid artery (ICA) and vertebral artery (VA), as well as the not directly observable distal ICA, middle cerebral artery (MCA), and basilar artery (BA). Stenosis at the origin of the ICA is mainly evaluated using the parameter peak systolic velocity (PSV), with values of ≥ 200-230 cm/s indicating severe stenosis. Recently, the acceleration time ratio has been reported for diagnosis of ICA origin stenosis.

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Muscle weakness is detrimental not only to quality of life but also life expectancy. However, effective drugs have still not been developed to improve and prevent muscle weakness associated with aging or diseases. One reason for the delay in drug discovery is that no suitable in vitro screening system has been established to test whether drugs improve muscle strength.

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The development of three-dimensional printers has facilitated the creation of patient-specific hollow vessel models. Preoperative simulations using these types of models have improved our ability to select appropriate devices and embolic materials before performing complex endovascular procedures. This report describes 2 cases of high-flow renal arteriovenous fistulas (r-AVFs) that were successfully treated via short-segment embolization using the preloading coil-in-plug (p-CIP) technique.

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Muscle fibres are broadly categorised into types I and II; the fibre-type ratio determines the contractile and metabolic properties of skeletal muscle tissue. The maintenance of type I fibres is essential for the prevention of obesity and the treatment of muscle atrophy caused by type 2 diabetes or unloading. Some reports suggest that myokines are related to muscle fibre type determination.

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Active inflammation generally promotes immune activation. However, in the tumor microenvironment (TME), active inflammation occurs in parallel with immunosuppression, and both contribute to tumor growth. Why inflammation does not lead to immune activation in TME remains unclear.

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Stroke requires rapid determination of the cause to provide timely and appropriate initial management. Various ultrasonographic techniques have been evaluated as ways to determine the cause of stroke; among them, carotid artery ultrasonography is particularly useful since it provides considerable information within a short time period when used to evaluate a specific site. In the emergency room, carotid artery ultrasonography can be used to diagnose internal carotid artery stenosis, predict an occluded vessel, and infer the cause of ischemic stroke.

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Cognitive training-induced neuroplastic brain changes have been reported. This prospective study evaluated whether microscopic fractional anisotropy (μFA) derived from double diffusion encoding (DDE) MRI could detect brain changes following a 4 week cognitive training. Twenty-nine healthy volunteers were recruited and randomly assigned into the training ( = 21) and control ( = 8) groups.

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Inspired by the induced-fit mechanism in nature, we developed the process of water-induced self-assembly (WISA) to make water an active substrate that regulates the self-assembly and function of amphiphilic discotic molecules (ADMs). The ADM is an isotropic liquid that self-assembles only when in contact with water. Characterization results indicate that water fits into the hydrophilic core of the ADMs and induces the formation of a hexagonal columnar phase (Col), where each column contains a hydrated artificial water channel (AWC).

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Patients with diffuse idiopathic skeletal hyperostosis (DISH) are at high risk for unstable vertebral fracture, which can be frequently missed. An 80-year-old man with pre-existing muscle lower limb weakness due to frailty was referred from another hospital, presenting with progressive urinary retention and its related symptoms, which had been treated as a urinary tract infection at previous hospital. One week prior to our visit, he had fallen.

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Newly introduced heat-not-burn or electronic cigarettes can cause lethal nicotine intoxication if ingested at higher doses. Although routine gastric lavage is not recommended, it should be considered if the amount of intoxicant is lethal. A 59-year-old man with a history of depression was brought to our emergency department after intentional ingestion of 8 heat-not-burn cigarettes, which were estimated to contain a total of 100 mg of nicotine.

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