Tomoyuki Nakamura

Dr. Tomoyuki Nakamura

orcid

Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 September 2022 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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JHJunji Hatakeyama
Junji Hatakeyama
SIShigeaki Inoue
Shigeaki Inoue
KLKEIBUN LIU
KEIBUN LIU
Kazuma YamakawaKazuma Yamakawa
Kazuma Yamakawa
TNTakeshi Nishida
Takeshi Nishida
KNKensuke Nakamura
Kensuke Nakamura
Introduction: Post-intensive care syndrome (PICS) is an emerging problem in critically ill patients and the prevalence and risk factors are unclear in patients with severe coronavirus disease 2019 (COVID-19). This multicenter prospective observational study aimed to investigate the prevalence and risk factors of PICS in ventilated patients with COVID-19 after ICU discharge. Methods: Questionnaires were administered twice in surviving patients with COVID-19 who had required mechanical ventilation, concerning Barthel Index, Short-Memory Questionnaire, and Hospital Anxiety and Depression Scale scores. The risk factors for PICS were examined using a multivariate logistic regression analysis. Results: The first and second PICS surveys were obtained at 5.5 and 13.5 months (mean) after ICU discharge, with 251 and 209 patients completing the questionnaires and with a prevalence of PICS of 58.6% and 60.8%, respectively, along with the highest percentages of cognitive impairment. Delirium (with an odds ratio of (OR) 2.34, 95% CI 1.1–4.9, and p = 0.03) and the duration of mechanical ventilation (with an OR of 1.29, 95% CI 1.05–1.58, and p = 0.02) were independently identified as the risk factors for PICS in the first PICS survey. Conclusion: Approximately 60% of the ventilated patients with COVID-19 experienced persistent PICS, especially delirium, and required longer mechanical ventilation.

23 September 2022 in Frontiers in Immunology
Verified
Journal Article
Open access
TMTakayuki Miyamoto
Takayuki Miyamoto
YHYoshitaka Honda
Yoshitaka Honda
KIKazushi Izawa
Kazushi Izawa
Nobuo KanazawaNobuo Kanazawa
Nobuo Kanazawa
SKSaori Kadowaki
Saori Kadowaki
TYTakahiro Yasumi
Takahiro Yasumi
Purpose: Upregulation of type I interferon (IFN) signaling has been increasingly detected in inflammatory diseases. Recently, upregulation of the IFN signature has been suggested as a potential biomarker of IFN-driven inflammatory diseases. Yet, it remains unclear to what extent type I IFN is involved in the pathogenesis of undifferentiated inflammatory diseases. This study aimed to quantify the type I IFN signature in clinically undiagnosed patients and assess clinical characteristics in those with a high IFN signature.Methods: The type I IFN signature was measured in patients’ whole blood cells. Clinical and biological data were collected retrospectively, and an intensive genetic analysis was performed in undiagnosed patients with a high IFN signature.Results: A total of 117 samples from 94 patients with inflammatory diseases, including 37 undiagnosed cases, were analyzed. Increased IFN signaling was observed in 19 undiagnosed patients, with 10 exhibiting clinical features commonly found in type I interferonopathies. Skin manifestations, observed in eight patients, were macroscopically and histologically similar to those found in proteasome-associated autoinflammatory syndrome. Genetic analysis identified novel mutations in the PSMB8 gene of one patient, and rare variants of unknown significance in genes linked to type I IFN signaling in four patients. A JAK inhibitor effectively treated the patient with the PSMB8 mutations. Patients with clinically quiescent idiopathic pulmonary hemosiderosis and A20 haploinsufficiency showed enhanced IFN signaling.Conclusions: Half of the patients examined in this study, with undifferentiated inflammatory diseases, clinically quiescent A20 haploinsufficiency, or idiopathic pulmonary hemosiderosis, had an elevated type I IFN signature.

6 February 2025 in Journal of Intensive Care
Verified
Journal Article
Open access
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JHJunji Hatakeyama
Junji Hatakeyama
KNKensuke Nakamura
Kensuke Nakamura
SIShigeaki Inoue
Shigeaki Inoue
KLKEIBUN LIU
KEIBUN LIU
Kazuma YamakawaKazuma Yamakawa
Kazuma Yamakawa
ONOsamu Nishida
Osamu Nishida
Background: Post-intensive care syndrome (PICS) affects the quality of life (QOL) of survivors of critical illness. Although PICS persists for a long time, the longitudinal changes in each component and their interrelationships over time both remain unclear. This multicenter prospective study investigated the 2-year trajectory of PICS and its components as well as factors contributing to deterioration or recovery in mechanically ventilated patients with coronavirus disease 2019 (COVID-19), and also attempted to identify possible countermeasures. Methods: Patients who survived COVID-19 requiring mechanical ventilation completed questionnaires on the Barthel index, Short-Memory Questionnaire, Hospital Anxiety and Depression Scale, and EuroQol 5 dimensions 5-level every six months over a two-year period. Scores were weighted to account for dropouts, and the trajectory of each functional impairment was evaluated with alluvial diagrams. The prevalence of PICS and factors impairing or restoring function were examined using generalized estimating equations considering trajectories. Results: Among 334 patients, PICS prevalence rates in the four completed questionnaires were 72.1, 78.5, 77.6, and 82.0%, with cognitive impairment being the most common and lower QOL being noted when multiple impairments coexisted. Physical function and QOL indicated that many patients exhibited consistent trends of either recovery or deterioration. In contrast, cognitive function and mental health revealed considerable variability, with many patients showing fluctuating ratings in the later surveys. Delirium was associated with worse physical and mental health and poor QOL, while prolonged ventilation was associated with poor QOL. Living with family was associated with the recovery of all functions and QOL, while extracorporeal membrane oxygenation (ECMO) was associated with the recovery of cognitive function and mental health. Conclusions: Critically ill patients had PICS for a long period and followed different trajectories for each impairment component. Based on trajectories, known PICS risk factors such as prolonged ventilation and delirium were associated with impaired recovery, while ECMO and the presence of family were associated with recovery from PICS. In critically ill COVID-19 patients, delirium management and family interventions may play an important role in promoting recovery from PICS. Trial registration number: UMIN000041276, August 01, 2020.

Verified
Journal Article
Open access
PDF file
YKYu Kato
Yu Kato
ONOsamu Nishida
Osamu Nishida
NKNaohide Kuriyama
Naohide Kuriyama
TNTomoyuki Nakamura
Tomoyuki Nakamura
TKTakahiro Kawaji
Takahiro Kawaji
YSYasuyo Shimomura
Yasuyo Shimomura
Neutrophil extracellular trap (NET) formation, an innate immune system response, is associated with thrombogenesis and vascular endothelial injury. Circulatory disorders due to microvascular thrombogenesis are one of the principal causes of organ damage. NET formation in organs contributes to the exacerbation of sepsis, which is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. We have previously reported that recombinant human soluble thrombomodulin (rTM) reduces lipopolysaccharide (LPS)-induced NET formation in vitro. Here, we aimed to show that thrombomodulin (TM)-mediated suppression of NET formation protects against organ damage in sepsis. Mice were injected intraperitoneally (i.p.) with 10 mg/kg LPS. rTM (6 mg/kg/day) or saline was administered i.p. 1 h after LPS injection. In the LPS-induced murine septic shock model, extracellular histones, which are components of NETs, were observed in the liver and lungs. In addition, the serum cytokine (interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), macrophage chemotactic protein-1 (MCP-1), and interleukin-10 (IL-10)) levels were increased. The administration of rTM in this model prevented NET formation in the organs and suppressed the increase in the levels of all cytokines except IL-1β. Furthermore, the survival rate improved. We provide a novel role of TM in treating inflammation and NETs in organs during sepsis.

26 March 2020 in Therapeutic Apheresis and Dialysis
Verified
Journal Article
Closed access
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TNTomoyuki Nakamura
Tomoyuki Nakamura
KMKazuhiro Moriyama
Kazuhiro Moriyama
YSYasuyo Shimomura
Yasuyo Shimomura
YKYu Kato
Yu Kato
NKNaohide Kuriyama
Naohide Kuriyama
ONOsamu Nishida
Osamu Nishida

1 July 2022 in Metabolites
Verified
Journal Article
Open access
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NKNaohide Kuriyama
Naohide Kuriyama
TNTomoyuki Nakamura
Tomoyuki Nakamura
HNHarumasa Nakazawa
Harumasa Nakazawa
TWTyler Wen
Tyler Wen
LBLorenzo Berra
Lorenzo Berra
Masao KanekiMasao Kaneki
Masao Kaneki
Mitochondrial dysfunction has been implicated in the pathogenesis of inflammation and multi-organ dysfunction in major trauma, including burn injury. Coenzyme Q10 (CoQ10) is a metabolite of the mevalonate pathway and an essential cofactor for the electron transport in the mitochondria. In addition, its reduced form (ubiquinol) functions as an antioxidant. Little is known as to whether oral CoQ10 supplementation effectively increases intracellular CoQ10 levels in humans. To study the bioavailability of CoQ10 supplementation, we conducted a randomized, double-blind, placebo-controlled study of reduced CoQ10 (ubiquinol-10) (1800 mg/day, t.i.d.) in burn patients at a single, tertiary-care hospital. Baseline plasma CoQ10 levels were significantly lower in burn patients than in healthy volunteers, although plasma CoQ10/cholesterol ratio did not differ between the groups. CoQ10 supplementation increased plasma concentrations of total and reduced CoQ10 and total CoQ10 content in peripheral blood mononuclear cells (PBMCs) in burn patients compared with the placebo group. CoQ10 supplementation did not significantly change circulating levels of mitochondrial DNA, inflammatory markers (e.g., interleukins, TNF-α, IFN-γ), or Sequential Organ Failure Assessment (SOFA) scores compared with the placebo group. This study showed that a relatively high dose of reduced CoQ10 supplementation increased the intracellular CoQ10 content in PBMCs as well as plasma concentrations in burn patients.