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  1. Article ; Online: A design principle of spindle oscillations in mammalian sleep

    Tetsuya Yamada / Shoi Shi / Hiroki R. Ueda

    iScience, Vol 25, Iss 3, Pp 103873- (2022)

    2022  

    Abstract: Summary: Neural oscillations are mainly regulated by molecular mechanisms and network connectivity of neurons. Large-scale simulations of neuronal networks have driven the population-level understanding of neural oscillations. However, cell-intrinsic ... ...

    Abstract Summary: Neural oscillations are mainly regulated by molecular mechanisms and network connectivity of neurons. Large-scale simulations of neuronal networks have driven the population-level understanding of neural oscillations. However, cell-intrinsic mechanisms, especially a design principle, of neural oscillations remain largely elusive. Herein, we developed a minimal, Hodgkin-Huxley-type model of groups of neurons to investigate molecular mechanisms underlying spindle oscillation, which is synchronized oscillatory activity predominantly observed during mammalian sleep. We discovered that slowly inactivating potassium channels played an essential role in characterizing the firing pattern. The detailed analysis of the minimal model revealed that leak sodium and potassium channels, which controlled passive properties of the fast variable (i.e., membrane potential), competitively regulated the base value and time constant of the slow variable (i.e., cytosolic calcium concentration). Consequently, we propose a theoretical design principle of spindle oscillations that may explain intracellular mechanisms behind the flexible control over oscillation density and calcium setpoint.
    Keywords Neuroscience ; Complex system biology ; Computer modeling ; Science ; Q
    Subject code 612
    Language English
    Publishing date 2022-03-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: A design principle of spindle oscillations in mammalian sleep.

    Yamada, Tetsuya / Shi, Shoi / Ueda, Hiroki R

    iScience

    2022  Volume 25, Issue 3, Page(s) 103873

    Abstract: Neural oscillations are mainly regulated by molecular mechanisms and network connectivity of neurons. Large-scale simulations of neuronal networks have driven the population-level understanding of neural oscillations. However, cell-intrinsic mechanisms, ... ...

    Abstract Neural oscillations are mainly regulated by molecular mechanisms and network connectivity of neurons. Large-scale simulations of neuronal networks have driven the population-level understanding of neural oscillations. However, cell-intrinsic mechanisms, especially a design principle, of neural oscillations remain largely elusive. Herein, we developed a minimal, Hodgkin-Huxley-type model of groups of neurons to investigate molecular mechanisms underlying spindle oscillation, which is synchronized oscillatory activity predominantly observed during mammalian sleep. We discovered that slowly inactivating potassium channels played an essential role in characterizing the firing pattern. The detailed analysis of the minimal model revealed that leak sodium and potassium channels, which controlled passive properties of the fast variable (i.e., membrane potential), competitively regulated the base value and time constant of the slow variable (i.e., cytosolic calcium concentration). Consequently, we propose a theoretical design principle of spindle oscillations that may explain intracellular mechanisms behind the flexible control over oscillation density and calcium setpoint.
    Language English
    Publishing date 2022-02-05
    Publishing country United States
    Document type Journal Article
    ISSN 2589-0042
    ISSN (online) 2589-0042
    DOI 10.1016/j.isci.2022.103873
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Estimating infection-related human mobility networks based on time series data of COVID-19 infection in Japan

    Yamada, Tetsuya / Shi, Shoi

    medRxiv

    Abstract: Comprehensive and evidence-based countermeasures against emerging infectious diseases have become increasingly important in recent years. COVID-19 and many other infectious diseases are spread by human movement and contact, but complex transportation ... ...

    Abstract Comprehensive and evidence-based countermeasures against emerging infectious diseases have become increasingly important in recent years. COVID-19 and many other infectious diseases are spread by human movement and contact, but complex transportation networks in 21 century make it difficult to predict disease spread in rapidly changing situations. It is especially challenging to estimate the network of infection transmission in the countries that the traffic and human movement data infrastructure is not yet developed. In this study, we devised a method to estimate the network of transmission of COVID-19 from the time series data of its infection and applied it to determine its spread across areas in Japan. We incorporated the effects of soft lockdowns, such as the declaration of a state of emergency, and changes in the infection network due to government-sponsored travel promotion, and predicted the spread of infection using the Tokyo Olympics as a model. The models used in this study are available online, and our data-driven infection network models are scalable, whether it be at the level of a city, town, country, or continent, and applicable anywhere in the world, as long as the time-series data of infections per region is available. These estimations of effective distance and the depiction of infectious disease networks based on actual infection data are expected to be useful in devising data-driven countermeasures against emerging infectious diseases worldwide.
    Keywords covid19
    Language English
    Publishing date 2021-08-04
    Publisher Cold Spring Harbor Laboratory Press
    Document type Article ; Online
    DOI 10.1101/2021.08.02.21261486
    Database COVID19

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  4. Article ; Online: The 103,200-arm acceleration dataset in the UK Biobank revealed a landscape of human sleep phenotypes.

    Katori, Machiko / Shi, Shoi / Ode, Koji L / Tomita, Yasuhiro / Ueda, Hiroki R

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 12, Page(s) e2116729119

    Abstract: SignificanceHuman sleep phenotypes are diversified by genetic and environmental factors, and a quantitative classification of sleep phenotypes would lead to the advancement of biomedical mechanisms underlying human sleep diversity. To achieve that, a ... ...

    Abstract SignificanceHuman sleep phenotypes are diversified by genetic and environmental factors, and a quantitative classification of sleep phenotypes would lead to the advancement of biomedical mechanisms underlying human sleep diversity. To achieve that, a pipeline of data analysis, including a state-of-the-art sleep/wake classification algorithm, the uniform manifold approximation and projection (UMAP) dimension reduction method, and the density-based spatial clustering of applications with noise (DBSCAN) clustering method, was applied to the 100,000-arm acceleration dataset. This revealed 16 clusters, including seven different insomnia-like phenotypes. This kind of quantitative pipeline of sleep analysis is expected to promote data-based diagnosis of sleep disorders and psychiatric disorders that tend to be complicated by sleep disorders.
    MeSH term(s) Acceleration ; Biological Specimen Banks ; Humans ; Phenotype ; Sleep ; Sleep Wake Disorders ; United Kingdom
    Language English
    Publishing date 2022-03-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2116729119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Impact of airline network on the global importation risk of mpox, 2022.

    Kinoshita, Ryo / Sassa, Miho / Otake, Shogo / Yoshimatsu, Fumi / Shi, Shoi / Ueno, Ryo / Suzuki, Motoi / Yoneoka, Daisuke

    Epidemiology and infection

    2023  Volume 151, Page(s) e60

    Abstract: From 1 January 2022 to 4 September 2022, a total of 53 996 mpox cases were confirmed globally. Cases are predominantly concentrated in Europe and the Americas, while other regions are also continuously observing imported cases. This study aimed to ... ...

    Abstract From 1 January 2022 to 4 September 2022, a total of 53 996 mpox cases were confirmed globally. Cases are predominantly concentrated in Europe and the Americas, while other regions are also continuously observing imported cases. This study aimed to estimate the potential global risk of mpox importation and consider hypothetical scenarios of travel restrictions by varying passenger volumes (PVs) via airline travel network. PV data for the airline network, and the time of first confirmed mpox case for a total of 1680 airports in 176 countries (and territories) were extracted from publicly available data sources. A survival analysis technique in which the hazard function was a function of effective distance was utilised to estimate the importation risk. The arrival time ranged from 9 to 48 days since the first case was identified in the UK on 6 May 2022. The estimated risk of importation showed that regardless of the geographic region, most locations will have an intensified importation risk by 31 December 2022. Travel restrictions scenarios had a minor impact on the global airline importation risk against mpox, highlighting the importance to enhance local capacities for the identification of mpox and to be prepared to carry out contact tracing and isolation.
    MeSH term(s) Humans ; Mpox (monkeypox) ; Travel ; Airports ; Contact Tracing ; Europe/epidemiology
    Language English
    Publishing date 2023-03-21
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 632982-2
    ISSN 1469-4409 ; 0950-2688
    ISSN (online) 1469-4409
    ISSN 0950-2688
    DOI 10.1017/S0950268823000456
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Time to Reconsider Diverse Ways of Working in Japan to Promote Social Distancing Measures against the COVID-19.

    Nomura, Shuhei / Yoneoka, Daisuke / Tanoue, Yuta / Kawashima, Takayuki / Shi, Shoi / Eguchi, Akifumi / Miyata, Hiroaki

    Journal of urban health : bulletin of the New York Academy of Medicine

    2020  Volume 97, Issue 4, Page(s) 457–460

    Keywords covid19
    Language English
    Publishing date 2020-06-30
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1435288-6
    ISSN 1468-2869 ; 1099-3460
    ISSN (online) 1468-2869
    ISSN 1099-3460
    DOI 10.1007/s11524-020-00464-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Ca

    Shi, Shoi / Ueda, Hiroki R

    BioEssays : news and reviews in molecular, cellular and developmental biology

    2017  Volume 40, Issue 1

    Abstract: Although we are beginning to understand the neuronal and biochemical nature of sleep regulation, questions remain about how sleep is homeostatically regulated. Beyond its importance in basic physiology, understanding sleep may also shed light on ... ...

    Abstract Although we are beginning to understand the neuronal and biochemical nature of sleep regulation, questions remain about how sleep is homeostatically regulated. Beyond its importance in basic physiology, understanding sleep may also shed light on psychiatric and neurodevelopmental disorders. Recent genetic studies in mammals revealed several non-secretory proteins that determine sleep duration. Interestingly, genes identified in these studies are closely related to psychiatric and neurodevelopmental disorders, suggesting that the sleep-wake cycle shares some common mechanisms with these disorders. Here we review recent sleep studies, including reverse and forward genetic studies, from the perspectives of sleep duration and homeostasis. We then introduce a recent hypothesis for mammalian sleep in which the fast and slow Ca
    MeSH term(s) Animals ; Calcium/physiology ; Calcium Channels/physiology ; Circadian Rhythm/genetics ; Circadian Rhythm/physiology ; Computational Biology ; Electrophysiological Phenomena ; Homeostasis/physiology ; Humans ; Models, Biological ; Neurodevelopmental Disorders/diagnosis ; Neurodevelopmental Disorders/genetics ; Neurodevelopmental Disorders/physiopathology ; Neurons/physiology ; Sleep/genetics ; Sleep/physiology
    Chemical Substances Calcium Channels ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2017-12-04
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 50140-2
    ISSN 1521-1878 ; 0265-9247
    ISSN (online) 1521-1878
    ISSN 0265-9247
    DOI 10.1002/bies.201700105
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: A jerk-based algorithm ACCEL for the accurate classification of sleep–wake states from arm acceleration

    Koji L. Ode / Shoi Shi / Machiko Katori / Kentaro Mitsui / Shin Takanashi / Ryo Oguchi / Daisuke Aoki / Hiroki R. Ueda

    iScience, Vol 25, Iss 2, Pp 103727- (2022)

    2022  

    Abstract: Summary: Arm acceleration data have been used to measure sleep–wake rhythmicity. Although several methods have been developed for the accurate classification of sleep–wake episodes, a method with both high sensitivity and specificity has not been fully ... ...

    Abstract Summary: Arm acceleration data have been used to measure sleep–wake rhythmicity. Although several methods have been developed for the accurate classification of sleep–wake episodes, a method with both high sensitivity and specificity has not been fully established. In this study, we developed an algorithm, named ACceleration-based Classification and Estimation of Long-term sleep–wake cycles (ACCEL) that classifies sleep and wake episodes using only raw accelerometer data, without relying on device-specific functions. The algorithm uses a derivative of triaxial acceleration (jerk), which can reduce individual differences in the variability of acceleration data. Applying a machine learning algorithm to the jerk data achieved sleep–wake classification with a high sensitivity (>90%) and specificity (>80%). A jerk-based analysis also succeeded in recording periodic activities consistent with pulse waves. Therefore, the ACCEL algorithm will be a useful method for large-scale sleep measurement using simple accelerometers in real-world settings.
    Keywords Chronobiology ; Diagnostic technique in health technology ; Health technology ; Science ; Q
    Subject code 006
    Language English
    Publishing date 2022-02-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: A jerk-based algorithm ACCEL for the accurate classification of sleep-wake states from arm acceleration.

    Ode, Koji L / Shi, Shoi / Katori, Machiko / Mitsui, Kentaro / Takanashi, Shin / Oguchi, Ryo / Aoki, Daisuke / Ueda, Hiroki R

    iScience

    2022  Volume 25, Issue 2, Page(s) 103727

    Abstract: Arm acceleration data have been used to measure sleep-wake rhythmicity. Although several methods have been developed for the accurate classification of sleep-wake episodes, a method with both high sensitivity and specificity has not been fully ... ...

    Abstract Arm acceleration data have been used to measure sleep-wake rhythmicity. Although several methods have been developed for the accurate classification of sleep-wake episodes, a method with both high sensitivity and specificity has not been fully established. In this study, we developed an algorithm, named ACceleration-based Classification and Estimation of Long-term sleep-wake cycles (ACCEL) that classifies sleep and wake episodes using only raw accelerometer data, without relying on device-specific functions. The algorithm uses a derivative of triaxial acceleration (jerk), which can reduce individual differences in the variability of acceleration data. Applying a machine learning algorithm to the jerk data achieved sleep-wake classification with a high sensitivity (>90%) and specificity (>80%). A jerk-based analysis also succeeded in recording periodic activities consistent with pulse waves. Therefore, the ACCEL algorithm will be a useful method for large-scale sleep measurement using simple accelerometers in real-world settings.
    Language English
    Publishing date 2022-01-01
    Publishing country United States
    Document type Journal Article
    ISSN 2589-0042
    ISSN (online) 2589-0042
    DOI 10.1016/j.isci.2021.103727
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: "KAIZEN" method realizing implementation of deep-learning models for COVID-19 CT diagnosis in real world hospitals.

    Okada, Naoki / Umemura, Yutaka / Shi, Shoi / Inoue, Shusuke / Honda, Shun / Matsuzawa, Yohsuke / Hirano, Yuichiro / Kikuyama, Ayano / Yamakawa, Miho / Gyobu, Tomoko / Hosomi, Naohiro / Minami, Kensuke / Morita, Natsushiro / Watanabe, Atsushi / Yamasaki, Hiroyuki / Fukaguchi, Kiyomitsu / Maeyama, Hiroki / Ito, Kaori / Okamoto, Ken /
    Harano, Kouhei / Meguro, Naohito / Unita, Ryo / Koshiba, Shinichi / Endo, Takuro / Yamamoto, Tomonori / Yamashita, Tomoya / Shinba, Toshikazu / Fujimi, Satoshi

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 1672

    Abstract: Numerous COVID-19 diagnostic imaging Artificial Intelligence (AI) studies exist. However, none of their models were of potential clinical use, primarily owing to methodological defects and the lack of implementation considerations for inference. In this ... ...

    Abstract Numerous COVID-19 diagnostic imaging Artificial Intelligence (AI) studies exist. However, none of their models were of potential clinical use, primarily owing to methodological defects and the lack of implementation considerations for inference. In this study, all development processes of the deep-learning models are performed based on strict criteria of the "KAIZEN checklist", which is proposed based on previous AI development guidelines to overcome the deficiencies mentioned above. We develop and evaluate two binary-classification deep-learning models to triage COVID-19: a slice model examining a Computed Tomography (CT) slice to find COVID-19 lesions; a series model examining a series of CT images to find an infected patient. We collected 2,400,200 CT slices from twelve emergency centers in Japan. Area Under Curve (AUC) and accuracy were calculated for classification performance. The inference time of the system that includes these two models were measured. For validation data, the slice and series models recognized COVID-19 with AUCs and accuracies of 0.989 and 0.982, 95.9% and 93.0% respectively. For test data, the models' AUCs and accuracies were 0.958 and 0.953, 90.0% and 91.4% respectively. The average inference time per case was 2.83 s. Our deep-learning system realizes accuracy and inference speed high enough for practical use. The systems have already been implemented in four hospitals and eight are under progression. We released an application software and implementation code for free in a highly usable state to allow its use in Japan and globally.
    MeSH term(s) Humans ; COVID-19/diagnostic imaging ; Artificial Intelligence ; Deep Learning ; Tomography, X-Ray Computed/methods ; Software ; COVID-19 Testing
    Language English
    Publishing date 2024-01-19
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-52135-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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