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1. Scanning near-field optical spectroscopy and carrier transport based analysis in mesoscopic regions for two-dimensional semiconductors

Author

Anri Sakurai, Kohei Iwamoto, Yoshihiko Miwa, Hirokazu Hori, Akira Ishikawa, Kazuharu Uchiyama, Kiyoshi Kobayashi, Katsumi Kishino, and Masaru Sakai

Subjects
Medicine, Science
Abstract

Abstract The measurements of photoexcited transport in mesoscopic regimes reveal the states and properties of mesoscopic systems. In this study, we focused on direct measurements of electromagnetic energy transports in the mesoscopic regions and constructed a scanning tunnelling microscope-assisted multi-probe scanning near-field optical microscope spectroscopy system. After producing an emission energy map through a single-probe measurement, two-probe measurement enables us to observe and analyse carrier transport characteristics. It suggests that exciton generation and transport in the mesoscopic region of semiconductors with quantum structure changes, such as the bias of dopant, affect the excited carrier emission recombination process. The measured probability density of the carrier transported with quantum effects can be used for applications in natural intelligence research by combining it with the analysis using tournament structures. Our developed measurement and analysis methods are expected to clarify the details of carrier's behaviour in the mesoscopic region in various materials and lead to applications for novel optoelectronic devices.

Published
2022
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2. A case of chronic progressive external ophthalmoplegia presenting with central neurogenic hyperventilation

Author

Mariko Sano, Tomoyo Shimada, Anri Sakurai, Yu-ichi Goto, Taiji Tsunemi, and Nobutaka Hattori

Subjects
Chronic progressive external ophthalmoplegia, Central neurogenic hyperventilation, Magnetic resonance spectroscopy, Neurology. Diseases of the nervous system, RC346-429
Abstract

We report a female patient with typical chronic progressive external ophthalmoplegia (CPEO) presented with central neurogenic hyperventilation (CNH), which is characterized by sustained hyperventilation during awake and sleep. CNH is usually caused by brain stem lesions. While her brain MRI was unremarkable, brain magnetic resonance spectroscopy revealed an increased lactate level in the frontal lobe, suggesting abnormal mitochondrial respiration. CPEO mainly presents a progressive weakness in extraocular muscles and rarely presents neurological symptoms, while abnormal respiration, including tachypnea, is relatively common in other mitochondrial disorders, such as Leigh syndrome, in which the apparent abnormal brain lesions were observed. These mitochondrial disorders, including CPEO, share the same mitochondrial gene mutations. This case illustrates the clinical heterogeneity of mitochondrial disorders.

Published
2022
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3. Effect of comorbid Parkinson’s disease and Parkinson’s disease dementia on the course of idiopathic normal pressure hydrocephalus

Author

Anri, Sakurai, Taiji, Tsunemi, Tomoyo, Shimada, Kaito, Kawamura, Madoka, Nakajima, Masakazu, Miyajima, and Nobutaka, Hattori

Subjects
mental disorders, General Medicine
Abstract

OBJECTIVE The objective of this study was to analyze the effect of concomitant Parkinson’s disease (PD) and PD dementia (PD/PDD) on the course of idiopathic normal pressure hydrocephalus (iNPH), especially as related to the outcome of lumboperitoneal shunt (LPS) surgery. METHODS The authors retrospectively analyzed patients with iNPH without accompanying disorders (iNPH alone [iNPHa]) and iNPH concomitant with PD/PDD (iNPHc+PD/PDD) who had presented to their department between 2010 and 2019. The diagnosis of iNPHc+PD/PDD was established using the diagnostic criteria of the Movement Disorder Society. The effect of LPS surgery on clinical symptoms and striatum volumes was evaluated. RESULTS Thirty-three patients with iNPHa and 23 patients with iNPHc+PD/PDD were identified. Comorbid PD/PDD significantly worsened clinical outcome as measured by the iNPH grading scale, modified Rankin Scale (mRS), and Hoehn and Yahr (HY) scale. LPS surgery improved the iNPH score including gait disturbance (p < 0.01), cognitive impairment (p = 0.02), and urinary disturbance (p < 0.01) in iNPHa and improved gait disturbance (p = 0.01) and urinary disturbance (p = 0.03) in iNPHc+PD/PDD for 1 year. Comorbid synucleinopathies maintained worse mRS scores and HY stages for 3 years, and LPS surgery extended overall survival (p = 0.003), as well as the period of sustained mRS scores (p = 0.04) and HY stages (p = 0.004) in iNPHc+PD/PDD. Both caudate and putamen volumes were reduced in iNPHa (p < 0.01) compared to those in controls and in patients with iNPHc+PD/PDD compared to those in patients with PD/PDD (p < 0.01), and LPS surgery restored caudate volumes in both groups. CONCLUSIONS These results revealed that comorbid PD/PDD deteriorates the clinical course of iNPH and that LPS surgery is recommended regardless of this comorbidity.

Published
2022

4. Comorbid alpha synucleinopathies in idiopathic normal pressure hydrocephalus

Author

Nobutaka Hattori, Taiji Tsunemi, Taku Hatano, Ayami Okuzumi, Yuta Ishiguro, and Anri Sakurai

Subjects
Lewy Body Disease, medicine.medical_specialty, Parkinson's disease, Neurology, Synucleinopathies, Comorbidity, behavioral disciplines and activities, Gastroenterology, Normal pressure hydrocephalus, Internal medicine, mental disorders, medicine, Humans, Dementia, Retrospective Studies, Dementia with Lewy bodies, business.industry, Parkinsonism, Parkinson Disease, medicine.disease, Hydrocephalus, Normal Pressure, nervous system diseases, Neurology (clinical), business
Abstract

This study aimed to determine the prevalence and clinical features of Parkinson’s disease (PD)/PD dementia (PD/PDD) or dementia with Lewy bodies (DLB) in idiopathic normal pressure hydrocephalus (iNPH). Patients with iNPH who were admitted to the Department of Neurology, Juntendo University School of Medicine over the past 10 years have been retrospectively analyzed. The diagnosis of iNPH and concomitant PD/PDD or DLB was established using diagnostic criteria. Motor symptoms were assessed by the Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) III. 123I-ioflupane single-photon emission computed tomography (DaT-SPECT) and cerebrospinal fluid (CSF) real-time quaking-induced conversion (RT-QuIC)-based assay were performed for alpha synuclein aggregation. Overall, 79 patients met the criteria for iNPH, of which 34 developed iNPH without accompanying disorders (iNPHa; 43%), 23 developed iNPH with comorbid PD/PDD (iNPHc + PD/PDD; 29.1%), and 8 developed iNPH with comorbid DLB (iNPHc + DLB; 10.1%). Significant differences in facial expansion and upper-limb parkinsonism were observed with a comorbidity of either PD/PDD or DLB. The specific binding ratio (SBR) of DaTscan was reduced in iNPHa (p = 0.02), but it reduced further with comorbid PD/PDD (p

Published
2021

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