Publications by authors named "Sasagawa A"

Arachnoid cysts have the potential to rupture, leading to the development of a subdural hygroma following minor trauma. Although surgery may be considered in cases of increased intracranial pressure (ICP) or regional neurological symptoms, the optimal approach remains unclear. We report a case of subdural hygroma due to a ruptured arachnoid cyst (SHrAC) with elevated ICP successfully treated with long-term subdural drainage for over 1 month.

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Article Synopsis
  • Sensorimotor learning involves changes in neuronal activity in the premotor (PM) and primary motor cortex (M1) of primates, as studied through calcium imaging in common marmosets during a reaching task.
  • During the learning process, the dorsorostral PM demonstrated earlier peak activity compared to the dorsocaudal PM and M1, with increased reaction times in pull trials closely correlating with PMdr activity.
  • The dorsocaudal PM and M1 maintained stable representation of movements, while PMdc neurons adjusted their preferred movement direction based on push trial performance, highlighting the transition from dynamic tuning in PMdc to stable motor representation in M1 during learning.
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Objective: The purpose of this study was to understand the anatomical and functional connections between the paracentral lobule (PCL) and the primary motor cortex (M1) of the human brain.

Methods: This retrospective study included 16 patients who underwent resection of lesions located near M1. Nine patients had lesions in the dominant hemisphere.

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Objective: This study aimed to enable the automatic detection of the hippocampus and diagnose mesial temporal lobe epilepsy (MTLE) with the hippocampus as the epileptogenic area using artificial intelligence (AI). We compared the diagnostic accuracies of AI and neurosurgical physicians for MTLE with the hippocampus as the epileptogenic area.

Method: In this study, we used an AI program to diagnose MTLE.

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Aim/introduction: This investigation aimed to clarify the relationship between cognitive function and blood glucose control in the elderly individuals with type 1 diabetes.

Materials And Methods: In total, 45 patients with type 1 diabetes, age 74.9 ± 6.

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The aim of the present study was to evaluate motor area mapping using functional magnetic resonance imaging (fMRI) compared with electrical cortical stimulation (ECS). Motor mapping with fMRI and ECS were retrospectively compared in seven patients with refractory epilepsy in which the primary motor (M1) areas were identified by fMRI and ECS mapping between 2012 and 2019. A right finger tapping task was used for fMRI motor mapping.

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Objective: The present study investigated the cortical areas and networks responsible for hyperkinetic seizures by analyzing invasive recordings and diffusion tensor imaging (DTI) tractography.

Methods: Seven patients with intractable focal epilepsy in whom hyperkinetic seizures were recorded during an invasive evaluation at Sapporo Medical University between January 2012 and March 2020 were enrolled in the present study. Intracranial recordings were analyzed to localize seizure-onset zones (SOZs) and symptomatogenic zones (spread areas at clinical onset).

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Purpose: The present study evaluated the utility of the steady-state responses of cortico-cortical evoked potentials (SSCCEPs) and compared them with the responses of conventional CCEPs.

Methods: Eleven patients with medically intractable focal epilepsy who underwent the implantation of subdural electrodes or stereoelectroencephalography were enrolled. Conventional CCEPs were obtained by averaging responses to alternating 1-Hz electrical stimuli, and 5-Hz stimuli were delivered for recording SSCCEPs.

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The aim of this study was to investigate histologically the amount of peri-implant tissue augmentation after volume-stable porcine collagen matrix transplantation. Six male beagle dogs were used in the experiment. P2, P4, and M1 distal roots were extracted under general anesthesia.

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This study investigated the networks originating from frontal eye fields (FEFs) using electric cortical stimulation and diffusion tensor imaging (DTI). Seven patients with intractable focal epilepsy, in which FEFs were identified by electrical cortical stimulation, were enrolled in this study. Electric stimulation at 50 Hz was applied to the electrodes for functional mapping.

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Gliomas are sometimes difficult to differentiate from strokes and are often misdiagnosed on magnetic resonance imaging (MRI); thus, the terms "stroke mimics" and "stroke chameleons" have been introduced. In this study, we analyzed stroke mimics and stroke chameleons in glioma and discussed the diagnostic perplexity.We retrospectively reviewed cases that were removed from lesions that were considered to be brain tumors.

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Several structures including subthalamic nucleus (STN), the caudal zona incerta (cZI), the prelemniscal radiation (Raprl), and the thalamic ventral intermediate nucleus (Vim) have been reported to be useful for improving symptoms of Parkinson's disease (PD). However, the effect of each target is still unclear. Therefore, we investigated each structure's effects and adverse effects using a directional lead implanted in the posterior STN adjacent to the cZI and Raprl in two patients with tremor-dominant PD.

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Background: Deep brain stimulation is an effective treatment for severe tremor in essential tremor and Parkinson disease (PD). However, progressive loss of the beneficial effects of deep brain stimulation may occur due to several factors.

Case Description: We assessed the effects of different temporal patterns of cycling stimulation in the posterior subthalamic area, subthalamic nucleus, and the ventral intermediate nucleus of the thalamus in 3 PD patients with early decline of tremor suppression associated with severe tremor rebound.

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Objective: The aim of the present study was to compare localization of the language cortex using electrical cortical stimulation (ECS) and functional magnetic resonance imaging (fMRI) to establish the relevance of fMRI language mapping.

Methods: Language mapping with fMRI and functional ECS mapping were retrospectively compared in ten patients with refractory epilepsy who underwent fMRI language mapping and functional ECS mapping between June 2012 and April 2019. A shiritori task, a popular Japanese word chain game, was used for fMRI language mapping.

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Introduction: This study investigated the networks of Negative motor areas (NMAs) using electric cortical stimulation and diffusion tensor imaging (DTI).

Methods: Twelve patients with intractable focal epilepsy, in which NMAs were identified by electrical cortical stimulation, were enrolled in this study. Electric stimulation at 50Hz was applied to the electrodes during motor tasks to identify the NMAs.

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Objectives: Parkinson's disease (PD) is a neurodegenerative disease presenting characteristic motor features. Severity is usually assessed by clinical symptoms; however, few objective indicators are available. In this study, we evaluated the utility of dopamine transporter (DAT) imaging and subthalamic nucleus (STN) activities as indicators of PD severity.

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Although deep brain stimulation (DBS) is an established treatment for Parkinson's disease, the long-term suppression of tremor is still a challenging issue. We report two patients with tremor-dominant Parkinson's disease (PD) treated with unilateral thalamotomy of the ventralis intermedius nucleus (Vim) combined with the subthalamic nucleus (STN)-DBS or the posterior subthalamic area (PSA)-DBS. One year after the surgery, thalamotomy of the area from the Vim to the PSA showed improvement not only in tremor but also in rigidity and akinesia.

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Numerous non-epileptic physiological electroencephalographic (EEG) patterns morphologically mimic epileptiform activity. However, misleading non-epileptic findings of electrocorticography (ECoG) have not yet been examined in detail. The aim of the present study was to identify non-epileptic epileptiform ECoG findings.

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Background: Vagus nerve stimulation is a palliative treatment for patients with refractory epilepsy; however, the misplacement of electrodes may cause complications and thus needs to be avoided.

Methods: We herein report an intraoperative monitoring technique to prevent the misplacement of electrodes. Endotracheal tube electrodes were inserted to record electromyographic activity from the vocal cords and identify the vagus nerve.

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The reaction of N-heteroaromatic compounds, such as 2-aryl-pyrrole, benzimidazole, imidazole, indole, and pyrazole derivatives, with alkynes in the presence of a catalytic amount of a nickel complex results in C-H/N-H oxidative annulation. The reaction shows a high functional group compatibility. While both Ni(0) and Ni(ii) complexes show a high catalytic activity, Ni(0) is proposed as a key catalytic species in the main catalytic cycle.

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Due to the recent development of multidetector row computed tomography (CT), hemodynamic parameters can now be conveniently obtained with CT perfusion. The purpose of this study is to characterize the hemodynamic parameters of CT perfusion in moyamoya disease, and to discuss the differences in collateral circulation between moyamoya disease and atherosclerotic disease. A total of 16 hemispheric sides of 15 patients with moyamoya disease and 10 hemispheric sides of 9 patients with atherosclerotic disease who underwent bypass surgery were included.

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Cooked and packed rice (CaPR), a popular rice product in Japan, is distributed with oxygen-absorbing agents and without refrigeration. When the final product was inoculated with spores of several strains of proteolytic Clostridium botulinum at a dose of 10(3) spores per g (2 x 10(5) spores per package) and incubated at 30 degrees C, the bacteria grew and produced neurotoxins in 40 days. To simulate more realistic cases of contamination, the same dose of spores was inoculated before the cooking process.

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Treatment of cells with a synthetic conjugate of DXR with GSH via glutaraldehyde (GSH-DXR) caused cytochrome c to be released from the mitochondria to the cytosol following potent activation of caspase-3 and -9 by typical DNA fragmentation. This apoptosis was regulated by the JNK-signaling pathway. In the present experiment, binding of GSH-DXR to GST P1-1 allosterically led to the disappearance of its enzyme activity and activated the kinase activity of JNK without dissociation of the JNK-GST P1-1 complex.

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A case of juvenile hepatocellular carcinoma (HCC) with congestive liver cirrhosis is reported. The patient was a 21-year-old woman. She had been diagnosed as having transposition of the great arteries, type 2, in 1978.

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5,10,15,20-Tetra(N-methyl-pyridinium-4-yl)-21H,23H-porphyrin has shown to bind to the major groove of AT-rich DNA predominantly through electrostatic interaction between positively charged N-methyl pyridinium moieties of the porphyrin and negatively charged phosphodiester backbone. Solution structure of the complex between the porphyrin and a double-stranded DNA fragment has been inferred from the measurements of the mixing time-dependent intermolecular nuclear Overhauser effects (NOEs).

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