Updated on 2025/11/10

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写真a

 
Ryo Saji
 
Organization
Yokohama City University Hospital Emergency Care Department Assistant Professor
Title
Assistant Professor
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Education

  • Yokohama City University   Graduate School of Medicine   Doctoral Degree Program

    2019.4 - 2023.9

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    Country: Japan

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Papers

  • Combining blood glucose and SpO2/FiO2 ratio facilitates prediction of imminent ventilatory needs in emergency room COVID-19 patients. International journal

    Kazuya Sakai, Kai Okoda, Mototsugu Nishii, Ryo Saji, Fumihiro Ogawa, Takeru Abe, Ichiro Takeuchi

    Scientific reports   13 ( 1 )   22718 - 22718   2023.12

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    Language:English   Publishing type:Research paper (scientific journal)  

    The increasing requirement of mechanical ventilation (MV) due to the novel coronavirus disease (COVID-19) is still a global threat. The aim of this study is to identify markers that can easily stratify the impending use of MV in the emergency room (ER). A total of 106 patients with COVID-19 requiring oxygen support were enrolled. Fifty-nine patients were provided MV 0.5 h (interquartile range: 0.3 to 1.4) post-admission. Clinical and laboratory data before intubation were collected. Using a multivariate logistic regression model, we identified four markers associated with the impending use of MV, including the ratio of peripheral blood oxygen saturation to fraction of inspired oxygen (SpO2/FiO2 ratio), alanine aminotransferase, blood glucose (BG), and lymphocyte counts. Among these markers, SpO2/FiO2 ratio and BG, which can be measured easily and immediately, showed higher accuracy (AUC: 0.88) than SpO2/FiO2 ratio alone (AUC: 0.84), despite no significant difference (DeLong test: P = 0.591). Moreover, even in patients without severe respiratory failure (SpO2/FiO2 ratio > 300), BG (> 138 mg/dL) was predictive of MV use. Measuring BG and SpO2/FiO2 ratio may be a simple and versatile new strategy to accurately identify ER patients with COVID-19 at high risk for the imminent need of MV.

    DOI: 10.1038/s41598-023-50075-7

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  • Utility of dual‐energy computed tomography in the association of <scp>COVID</scp> ‐19 pneumonia severity Reviewed

    Takahiro Michishita, Ryo Saji, Hiroshi Miyazaki, Sena Mishima, Kosuke Shimada, Sakura Minami, Hiromu Okano, Naoya Suzuki, Tsuyoshi Otsuka, Takeru Abe, Ichiro Takeuchi, Ryosuke Furuya

    Acute Medicine &amp; Surgery   9 ( 1 )   2022.1

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    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/ams2.811

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ams2.811

  • Prostaglandin-E2 receptor-4 stimulant rescues cardiac malfunction during myocarditis and protects the heart from adverse ventricular remodeling after myocarditis Reviewed

    Akira Takakuma, Mototsugu Nishii, Alan Valaperti, Haruto Hiraga, Ryo Saji, Kazuya Sakai, Reo Matsumura, Yasuo Miyata, Nozomu Oba, Fumiya Nunose, Fumihiro Ogawa, Kouichi Tamura, Ichiro Takeuchi

    Scientific Reports   11 ( 1 )   2021.10

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    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    Abstract

    Cardioprotective effect of prostaglandin-E2 receptor-4 (EP4) stimulation on the ischemic heart has been demonstrated. Its effect on the heart affected by myocarditis, however, remains uncertain. In this study, we investigated therapeutic effect of EP4 stimulant using a mouse model of autoimmune myocarditis (EAM) that progresses to dilated cardiomyopathy (DCM). EP4 was present in the hearts of EAM mice. Treatment with EP4 agonist (ONO-0260164: 20 mg/kg/day) improved an impaired left ventricular (LV) contractility and reduction of blood pressure on day 21, a peak myocardial inflammation. Alternatively, DCM phenotype, characterized by LV dilation, LV systolic dysfunction, and collagen deposition, was observed on day 56, along with activation of matrix metalloproteinase (MMP)-2 critical for myocardial extracellular matrix disruption, indicating an important molecular mechanism underlying adverse ventricular remodeling after myocarditis. Continued treatment with ONO-0260164 alleviated the DCM phenotype, but this effect was counteracted by its combination with a EP4 antagonist. Moreover, ONO-0260164 inhibited in vivo proteolytic activity of MMP-2 in association with up-regulation of tissue inhibitor of metalloproteinase (TIMP)-3. EP4 stimulant may be a promising and novel therapeutic agent that rescues cardiac malfunction during myocarditis and prevents adverse ventricular remodeling after myocarditis by promoting the TIMP-3/MMP-2 axis.

    DOI: 10.1038/s41598-021-99930-5

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    Other Link: https://www.nature.com/articles/s41598-021-99930-5

  • Identification of serum prognostic biomarkers of severe COVID-19 using a quantitative proteomic approach Reviewed

    Yayoi Kimura, Yusuke Nakai, Jihye Shin, Miyui Hara, Yuriko Takeda, Sousuke Kubo, Sundararaj Stanleyraj Jeremiah, Yoko Ino, Tomoko Akiyama, Kayano Moriyama, Kazuya Sakai, Ryo Saji, Mototsugu Nishii, Hideya Kitamura, Kota Murohashi, Kouji Yamamoto, Takeshi Kaneko, Ichiro Takeuchi, Eri Hagiwara, Takashi Ogura, Hideki Hasegawa, Tomohiko Tamura, Takeharu Yamanaka, Akihide Ryo

    Scientific Reports   11 ( 1 )   2021.10

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    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    Abstract

    The COVID-19 pandemic is an unprecedented threat to humanity that has provoked global health concerns. Since the etiopathogenesis of this illness is not fully characterized, the prognostic factors enabling treatment decisions have not been well documented. Accurately predicting the progression of the disease would aid in appropriate patient categorization and thus help determine the best treatment option. Here, we have introduced a proteomic approach utilizing data-independent acquisition mass spectrometry (DIA-MS) to identify the serum proteins that are closely associated with COVID-19 prognosis. Twenty-seven proteins were differentially expressed between severely ill COVID-19 patients with an adverse or favorable prognosis. Ingenuity Pathway Analysis revealed that 15 of the 27 proteins might be regulated by cytokine signaling relevant to interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF), and their differential expression was implicated in the systemic inflammatory response and in cardiovascular disorders. We further evaluated practical predictors of the clinical prognosis of severe COVID-19 patients. Subsequent ELISA assays revealed that CHI3L1 and IGFALS may serve as highly sensitive prognostic markers. Our findings can help formulate a diagnostic approach for accurately identifying COVID-19 patients with severe disease and for providing appropriate treatment based on their predicted prognosis.

    DOI: 10.1038/s41598-021-98253-9

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    Other Link: https://www.nature.com/articles/s41598-021-98253-9

  • Temporal change in Syndecan-1 as a therapeutic target and a biomarker for the severity classification of COVID-19 Reviewed

    Fumihiro Ogawa, Yasufumi Oi, Kento Nakajima, Reo Matsumura, Tomoki Nakagawa, Takao Miyagawa, Kazuya Sakai, Ryo Saji, Hayato Taniguchi, Kohei Takahashi, Takeru Abe, Masayuki Iwashita, Mototsugu Nishii, Ichiro Takeuchi

    Thrombosis Journal   19 ( 1 )   2021.8

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    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    Abstract

    Background

    Coronavirus disease 2019 (COVID-19) pneumonitis associated with severe respiratory failure is associated with high mortality. The pathogenesis of COVID-19 is associated with microembolism or microvascular endothelial injuries. Here, we report that syndecan-1 (SDC-1), a component of the endothelial glycocalyx, may be a biomarker of severity classification for COVID-19 related to endothelial injury.

    Methods and analysis

    We analyzed the data of COVID-19 patients for 1 year from February 2020 at Yokohama City University Hospital and Yokohama City University Medical Center Hospital. We selected COVID-19 patients who required admission care, including intensive care, and analyzed the classification of severe and critical COVID-19 retrospectively, using various clinical data and laboratory data with SDC-1 by ELISA.

    Results

    We analyzed clinical and laboratory data with SDC-1 in five severe COVID-19 and ten critical COVID-19 patients. In the two groups, their backgrounds were almost the same. In laboratory data, the LDH, CHE, and CRP levels showed significant differences in each group (P = 0.032, P &lt; 0.0001, and P = 0.007, respectively) with no significant differences in coagulation-related factors (platelet, PT-INR, d-dimer, ISTH score; P = 0.200, 0.277, 0.655, and 0.36, respectively). For the clinical data, the SOFA score was significantly different from admission day to day 14 of admission (p &lt; 0.0001). The SDC-1 levels of critical COVID-19 patients were significantly higher on admission day and all-time course compared with the levels of severe COVID-19 patients (P = 0.009 and P &lt; 0.0001, respectively).

    Conclusions

    Temporal change of SDC-1 levels closely reflect the severity of COVID-19, therefore, SDC-1 may be a therapeutic target and a biomarker for the severity classification of Covid-19.

    DOI: 10.1186/s12959-021-00308-4

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    Other Link: https://link.springer.com/article/10.1186/s12959-021-00308-4/fulltext.html

  • Combining IL-6 and SARS-CoV-2 RNAaemia-based risk stratification for fatal outcomes of COVID-19 Reviewed

    Ryo Saji, Mototsugu Nishii, Kazuya Sakai, Kei Miyakawa, Yutaro Yamaoka, Tatsuma Ban, Takeru Abe, Yutaro Ohyama, Kento Nakajima, Taro Hiromi, Reo Matsumura, Naoya Suzuki, Hayato Taniguchi, Tsuyoshi Otsuka, Yasufumi Oi, Fumihiro Ogawa, Munehito Uchiyama, Kohei Takahashi, Masayuki Iwashita, Yayoi Kimura, Satoshi Fujii, Ryosuke Furuya, Tomohiko Tamura, Akihide Ryo, Ichiro Takeuchi

    PLOS ONE   16 ( 8 )   e0256022 - e0256022   2021.8

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    Authorship:Lead author   Publishing type:Research paper (scientific journal)   Publisher:Public Library of Science (PLoS)  

    Background

    The coronavirus disease 2019 (COVID-19) pandemic rapidly increases the use of mechanical ventilation (MV). Such cases further require extracorporeal membrane oxygenation (ECMO) and have a high mortality.

    Objective

    We aimed to identify prognostic biomarkers pathophysiologically reflecting future deterioration of COVID-19.

    Methods

    Clinical, laboratory, and outcome data were collected from 102 patients with moderate to severe COVID-19. Interleukin (IL)-6 level and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copy number in plasma were assessed with ELISA kit and quantitative PCR.

    Results

    Twelve patients died or required ECMO owing to acute respiratory distress syndrome despite the use of MV. Among various variables, a ratio of oxygen saturation to fraction of inspired oxygen (SpO2/FiO2), IL-6, and SARS-CoV-2 RNA on admission before intubation were strongly predictive of fatal outcomes after the MV use. Moreover, among these variables, combining SpO2/FiO2, IL-6, and SARS-CoV-2 RNA showed the highest accuracy (area under the curve: 0.934). In patients with low SpO2/FiO2 (&lt; 261), fatal event-rate after the MV use at the 30-day was significantly higher in patients with high IL-6 (&gt; 49 pg/mL) and SARS-CoV-2 RNAaemia (&gt; 1.5 copies/μL) compared to those with high IL-6 or RNAaemia or without high IL-6 and RNAaemia (88% vs. 22% or 8%, log-rank test P = 0.0097 or P &lt; 0.0001, respectively).

    Conclusions

    Combining SpO2/FiO2 with high IL-6 and SARS-CoV-2 RNAaemia which reflect hyperinflammation and viral overload allows accurately and before intubation identifying COVID-19 patients at high risk for ECMO use or in-hospital death despite the use of MV.

    DOI: 10.1371/journal.pone.0256022

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  • Whole Nucleocapsid Protein of Severe Acute Respiratory Syndrome Coronavirus 2 May Cause False-Positive Results in Serological Assays. Reviewed International journal

    Yutaro Yamaoka, Sundararaj S Jeremiah, Kei Miyakawa, Ryo Saji, Mototsugu Nishii, Ichiro Takeuchi, Akihide Ryo

    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America   72 ( 7 )   1291 - 1292   2021.4

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  • Serum cholinesterase associated with COVID-19 pneumonia severity and mortality Reviewed

    Kento Nakajima, Takeru Abe, Ryo Saji, Fumihiro Ogawa, Hayato Taniguchi, Keishi Yamaguchi, Kazuya Sakai, Tomoki Nakagawa, Reo Matsumura, Yasufumi Oi, Mototsugu Nishii, Ichiro Takeuchi

    Journal of Infection   82 ( 2 )   282 - 327   2021.2

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.jinf.2020.08.021

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  • Rapid quantitative screening assay for SARS-CoV-2 neutralizing antibodies using HiBiT-tagged virus-like particles Reviewed

    Kei Miyakawa, Sundararaj Stanleyraj Jeremiah, Norihisa Ohtake, Satoko Matsunaga, Yutaro Yamaoka, Mayuko Nishi, Takeshi Morita, Ryo Saji, Mototsugu Nishii, Hirokazu Kimura, Hideki Hasegawa, Ichiro Takeuchi, Akihide Ryo

    Journal of Molecular Cell Biology   12 ( 12 )   987 - 990   2020.9

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    Publishing type:Research paper (scientific journal)   Publisher:Oxford University Press (OUP)  

    DOI: 10.1093/jmcb/mjaa047

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    Other Link: http://academic.oup.com/jmcb/article-pdf/12/12/987/36546013/mjaa047.pdf

  • O抗原と敗血症性ショック Reviewed

    酒井 和也, 西井 基継, 佐治 龍, 廣見 太郎, 小川 史洋, 竹内 一郎

    感染症学雑誌   94 ( 臨増 )   291 - 291   2020.3

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    Language:Japanese   Publisher:(一社)日本感染症学会  

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  • O抗原と敗血症性ショック

    酒井 和也, 西井 基継, 佐治 龍, 廣見 太郎, 小川 史洋, 竹内 一郎

    感染症学雑誌   94 ( 臨増 )   291 - 291   2020.3

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    Language:Japanese   Publisher:(一社)日本感染症学会  

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  • 敗血症に伴うショックに依存しない腎障害について動物モデルを用いた検討 Reviewed

    酒井 和也, 西井 基継, 小見 奈子, 佐治 龍, 小川 史洋, 竹内 一郎

    日本救急医学会雑誌   30 ( 9 )   662 - 662   2019.9

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    Language:Japanese   Publisher:(一社)日本救急医学会  

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MISC

  • 機械学習を用いた重症COVID-19の層別化における臨床的有用性の予備的検討

    酒井 和也, 西井 基継, 佐治 龍, 松村 玲生, 小川 史洋, 安部 猛, 豊田 洋, 小山 洋史, 竹内 一郎

    日本臨床救急医学会雑誌   25 ( 2 )   397 - 397   2022.5

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    Language:Japanese   Publisher:(一社)日本臨床救急医学会  

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  • 【Challenge to Change】Physician scientistのすすめ〜次世代の救急医療を担う君達へ〜 COVID-19研究の教訓から得たPhysician-Scientistに必要な素養の提言

    酒井 和也, 西井 基継, 松村 怜生, 佐治 龍, 小川 史洋, 安部 猛, 竹内 一郎

    日本救急医学会雑誌   32 ( 12 )   1281 - 1281   2021.11

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    Language:Japanese   Publisher:(一社)日本救急医学会  

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  • 機械学習を用いたCOVID-19患者の予後予測の検討

    大小田 凱, 酒井 和也, 佐治 龍, 松村 玲生, 小川 史洋, 西井 基継, 竹内 一郎

    日本救急医学会雑誌   32 ( 12 )   2730 - 2730   2021.11

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Research Projects

  • 心不全治療における新規創薬基盤の構築:LVAD患者を対象とした機械的減負荷モデル

    Grant number:25K11374  2025.4 - 2028.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    北里 梨紗, 佐治 龍, 西井 基継, 飯田 祐一郎

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    Grant amount:\6240000 ( Direct Cost: \4800000 、 Indirect Cost:\1440000 )

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  • Exploration of Severe ARDS Pathogenesis Using Proteome Analysis

    Grant number:24K12183  2024.4 - 2027.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant amount:\4550000 ( Direct Cost: \3500000 、 Indirect Cost:\1050000 )

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