Publications by authors named "Hiroki Sugihara"

The Kondo effect between localized f-electrons and conductive carriers leads to exotic physical phenomena. Among them, heavy-fermion (HF) systems, in which massive effective carriers appear due to the Kondo effect, have fascinated many researchers. Dimensionality is also an important characteristic of the HF system, especially because it is strongly related to quantum criticality.

View Article and Find Full Text PDF

In reversal learning tasks, the behavior of humans and animals is often assumed to be uniform within single experimental sessions to facilitate data analysis and model fitting. However, behavior of agents can display substantial variability in single experimental sessions, as they execute different blocks of trials with different transition dynamics. Here, we observed that in a deterministic reversal learning task, mice display noisy and sub-optimal choice transitions even at the expert stages of learning.

View Article and Find Full Text PDF

Clustering of supernumerary centrosomes, which potentially leads to cell survival and chromosomal instability, is frequently observed in cancers. However, the molecular mechanisms that control centrosome clustering remain largely unknown. The centrosomal kinesin KIF24 was previously shown to restrain the assembly of primary cilia in mammalian cells.

View Article and Find Full Text PDF

BACKGROUND Thallium-201 has been widely used in clinical practice for the management of coronary heart disease, but little is known regarding its kinetics in the acute phase of myocardial infarction. CASE REPORT We report a 78-year-old man who developed acute inferior myocardial infarction during exercise thallium-201 scintigraphy. The patient underwent exercise testing with thallium-201 myocardial scintigraphy because of a single episode of chest pain.

View Article and Find Full Text PDF

Prognostic prediction has been reported to affect the decision of doctors and non-physician health care providers such as nurses, social workers, pastors, and hospice volunteers on the selection of appropriate medical interventions. This was a case of a 65-year-old woman who presented with a poor oral intake. The patient had a history of sigmoid colon cancer with abdominal wall metastasis and peritoneal dissemination.

View Article and Find Full Text PDF

The structure of brain regions is assumed to correlate with their function, but there are very few instances in which the relationship has been demonstrated in the live brain. This is due to the difficulty of simultaneously measuring functional and structural properties of brain areas, particularly at cellular resolution. Here, we performed label-free, third-harmonic generation (THG) microscopy to obtain a key structural signature of cortical areas, their effective attenuation lengths (EAL), in the vertical columns of functionally defined primary visual cortex and five adjacent visual areas in awake mice.

View Article and Find Full Text PDF

Acute inferior myocardial damage can induce transient bradycardia and hypotension-the Bezold-Jarisch reflex, which is explained by the preferential distribution of vagal nerves in the inferior wall of the left ventricle. We report a 76-year-old man who showed a perfusion defect in the inferior wall with redistribution on exercise scintigraphy with thallium-201. Of note, during exercise at an intensity of 100 watts, the patient's heart rate transiently decreased from 122 to 95 bpm in sinus rhythm, accompanied by ST-segment depression.

View Article and Find Full Text PDF

 Technetium-99m-pyrophosphate (Tc-PYP) has been used, in combination with thallium-201, to estimate the site and extent of myocardial infarcts. We report a case of acute myocardial infarction with severe coronary disease in which the distribution of Tc-PYP was extensive. A 78-year-old man presented with dyspnea, and a diagnosis of non-ST-segment elevation acute myocardial infarction was made.

View Article and Find Full Text PDF

Isolated septal myocardial infarction is an uncommon condition with diagnostic difficulty due to small infarction size and anatomical variations. We report a case of isolated septal myocardial infarction, in which the diagnosis was confirmed not by electrocardiographic, echocardiographic, or angiographic findings, but by nuclear imaging. A 46-year-old man with chest discomfort exhibited ST-segment elevations in leads V and V, and borderline abnormalities of the septal wall motion on echocardiography.

View Article and Find Full Text PDF

Two-photon microscopy is used to image neuronal activity, but has severe limitations for studying deeper cortical layers. Here, we developed a custom three-photon microscope optimized to image a vertical column of the cerebral cortex > 1 mm in depth in awake mice with low (<20 mW) average laser power. Our measurements of physiological responses and tissue-damage thresholds define pulse parameters and safety limits for damage-free three-photon imaging.

View Article and Find Full Text PDF

Hypertrophic cardiomyopathy (HCM) patients sometimes develop subendocardial ischemia without coronary artery stenosis. We report a case of non-obstructive HCM, in which electrocardiographic changes were observed with improvement of subendocardial ischemia. A 76-year-old man presented with chest pain on exertion.

View Article and Find Full Text PDF

Acetylcholine (ACh) modulates diverse vital brain functions. Cholinergic neurons from the basal forebrain innervate a wide range of cortical areas, including the primary visual cortex (V1), and multiple cortical cell types have been found to be responsive to ACh. Here we review how different cell types contribute to different cortical functions modulated by ACh.

View Article and Find Full Text PDF

Multiple hypothalamic neuronal populations that regulate energy balance have been identified. Although hypothalamic glia exist in abundance and form intimate structural connections with neurons, their roles in energy homeostasis are less known. Here we show that selective Ca activation of glia in the mouse arcuate nucleus (ARC) reversibly induces increased food intake while disruption of Ca signaling pathway in ARC glia reduces food intake.

View Article and Find Full Text PDF

We retrospectively analyzed the outcomes of 175 consecutive patients admitted to our hospital between April 2004 and June 2014, and identified 42 (24%), 80 (46%), and 53 (30%) patients ≥ 80, 66-79, and ≤ 65 years old, respectively. The median progression-free survival (PFS) and overall survival (OS) of the ≥ 80, 66-79, and ≤ 65 years old groups were 19.1, 26.

View Article and Find Full Text PDF

Cholinergic modulation of cortex powerfully influences information processing and brain states, causing robust desynchronization of local field potentials and strong decorrelation of responses between neurons. We found that intracortical cholinergic inputs to mouse visual cortex specifically and differentially drive a defined cortical microcircuit: they facilitate somatostatin-expressing (SOM) inhibitory neurons that in turn inhibit parvalbumin-expressing inhibitory neurons and pyramidal neurons. Selective optogenetic inhibition of SOM responses blocked desynchronization and decorrelation, demonstrating that direct cholinergic activation of SOM neurons is necessary for this phenomenon.

View Article and Find Full Text PDF

Although thallium-201 exercise scintigraphy has been established for the detection of myocardial ischemia and viability, little is known regarding the myocardial thallium-201 kinetics during angioplasty. Herein, we report a 77-year-old man with angina pectoris, in whom serial myocardial imaging after a single dose of thallium-201 was helpful in identifying not only the culprit lesion and myocardial viability, but also the dynamic changes in myocardial perfusion during angioplasty. Thallium-201 images after exercise showed a perfusion defect in the inferior wall, with a trivial redistribution 3 hours after the exercise and a marked improvement 24 hours later.

View Article and Find Full Text PDF

The emergence of oligoclonal bands (OB) has been reported in patients with multiple myeloma (MM) after stem cell transplantation (SCT) or successful chemotherapy. However, their clinical relevance remains unclear. We reviewed the clinical records of MM patients from January 2006 to May 2014.

View Article and Find Full Text PDF

The brain uses attention and expectation as flexible devices for optimizing behavioral responses associated with expected but unpredictably timed events. The neural bases of attention and expectation are thought to engage higher cognitive loci; however, their influence at the level of primary visual cortex (V1) remains unknown. Here, we asked whether single-neuron responses in monkey V1 were influenced by an attention task of unpredictable duration.

View Article and Find Full Text PDF

An abnormal blood pressure response to exercise has been reported to be associated with left ventricular subendocardial ischemia in patients with hypertrophic cardiomyopathy (HCM), but the underlying mechanism remains unclear. We report a case of HCM with an abnormal blood pressure response and subendocardial ischemia, in which the analysis of heart rate variability revealed exercise-induced vagal enhancement. The present case highlights the possible mechanism linking abnormal blood pressure response and left ventricular subendocardial ischemia in patients with HCM.

View Article and Find Full Text PDF

The visual cortex provides powerful evidence for experience-dependent plasticity during development, and for stimulus and reinforcement-dependent plasticity in adulthood. The synaptic and circuit mechanisms underlying such plasticity are being progressively understood. Increasing evidence supports the hypothesis that plasticity in both the developing and adult visual cortex is initiated by a transient reduction of inhibitory drive, and implemented by persistent changes at excitatory synapses.

View Article and Find Full Text PDF

Hypertrophic cardiomyopathy (HCM) patients often develop subendocardial ischemia in the left ventricle without atherosclerotic coronary stenosis. Myocardial ischemia plays an important role in the pathophysiology of HCM, but diagnostic techniques for the detection of subendocardial ischemia have not been widely available. We developed specific techniques to quantify subendocardial ischemia on stress scintigraphy, and have compared the results with various clinical features in patients with HCM.

View Article and Find Full Text PDF

Masquerading bundle branch block is a rare and unique finding on a 12-lead electrocardiogram, consisting of the pattern of right bundle branch block in the precordial leads and left bundle branch block in the limb leads. We experienced a 77-year-old woman with masquerading bundle branch block. She had been well, but died suddenly 9 months after the diagnosis of masquerading bundle branch block.

View Article and Find Full Text PDF

A rare recurrent chromosomal translocation, t(14;19)(q32;q13), has been identified in a variety of B-cell malignancies, including chronic lymphocytic leukemia (CLL). We report a unique case of CLL in a patient carrying both trisomy 12 and t(14;19) (q32;q13.1), in whom t(11;14)(q13;q32) developed at relapse.

View Article and Find Full Text PDF