Hidekazu Yamamoto

Dr. Hidekazu Yamamoto

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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15 February 2017 in The Journal of Immunology
Verified
Journal Article
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MHMasaki Honda
Masaki Honda
TTTakayuki Takeichi
Takayuki Takeichi
SHShintaro Hashimoto
Shintaro Hashimoto
DYDaiki Yoshii
Daiki Yoshii
KIKaori Isono
Kaori Isono
YIYukihiro Inomata
Yukihiro Inomata
Neutrophils are considered responsible for the pathophysiological changes resulting from hepatic ischemia-reperfusion (I/R) injury, which is a complication of trauma, shock, liver resection, and transplantation. Recently, evidence is accumulating that formyl-peptide receptor (FPR) signaling constitutes an important danger signal that guides neutrophils to sites of inflammation. This study aimed to investigate dynamic neutrophil recruitment using two-photon laser-scanning microscopy (TPLSM) in response to FPR1 blockade during hepatic I/R. LysM-eGFP mice were subjected to partial warm hepatic I/R. They were pretreated with an FPR1 antagonist, cyclosporine H (CsH), or formyl peptide, fMLF. Liver was imaged after hepatic laser irradiation or I/R using the TPLSM technique. CsH treatment alleviated hepatic I/R injury, as evidenced by decreased serum transaminase levels, reduced hepatocyte necrosis/apoptosis, and diminished inflammatory cytokine, chemokine, and oxidative stress. In contrast, systemic administration of fMLF showed few effects. Time-lapse TPLSM showed that FPR1 blockade inhibited the accumulation of neutrophils in the necrotic area induced by laser irradiation in vivo. In the CsH-treated I/R group, the number and crawling velocity of neutrophils in the nonperfused area were lower than those in the control group. Meanwhile, FPR1 blockade did not affect monocyte/macrophage recruitment. Hepatic I/R promoted the retention of neutrophils and their active behavior in the spleen, whereas CsH treatment prevented their changes. Intravital TPLSM revealed that formyl-peptide–FPR1 signaling is responsible for regulating neutrophil chemotaxis to allow migration into the necrotic area in hepatic I/R. Our findings suggest effective approaches for elucidating the mechanisms of immune cell responses in hepatic I/R.

4 August 2019 in Liver Transplantation
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Journal Article
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HYHidekazu Yamamoto
Hidekazu Yamamoto
SKShirin E. Khorsandi
Shirin E. Khorsandi
MCMiriam Cortes‐Cerisuelo
Miriam Cortes‐Cerisuelo
YKYoichi Kawano
Yoichi Kawano
ADAnil Dhawan
Anil Dhawan
NHNigel Heaton
Nigel Heaton
Liver transplantation (LT) for small infants remains challenging because of the demands related to graft selection, surgical technique, and perioperative management. The aim of this study was to evaluate the short‐term and longterm outcomes of LT regarding vascular/biliary complications, renal function, growth, and patient/graft survival in infants ≤3 months compared with those of an age between >3 and 6 months at a single transplant center. A total of 64 infants ≤6 months underwent LT and were divided into 2 groups according to age at LT: those of age ≤3 months (range, 6‐118 days; XS group, n = 37) and those of age >3 to ≤6 months (range, 124‐179 days; S group, n = 27) between 1989 and 2014. Acute liver failure was the main indication for LT in the XS group (n = 31, 84%) versus S (n = 7, 26%). The overall incidence of hepatic artery thrombosis and portal vein thrombosis/stricture were 5.4% and 10.8% in the XS group and 7.4% and 11.1% in the S group, respectively (not significant). The overall incidence of biliary stricture and leakage were 5.4% and 2.7% in the XS group and 3.7% and 3.7% in the S group, respectively (not significant). There was no significant difference between the 2 groups in terms of renal function. No significant difference was found between the 2 groups for each year after LT in terms of height and weight z score. The 1‐, 5‐, and 10‐year patient survival rates were 70.3%, 70.3%, and 70.3% in the XS group compared with 92.6%, 88.9%, and 88.9% in the S group, respectively (not significant). In conclusion, LT for smaller infants has acceptable outcomes despite the challenges of surgical technique, including vascular reconstruction and graft preparation, and perioperative management.

21 December 2020 in Liver Transplantation
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Journal Article
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YSYuzuru Sambommatsu
Yuzuru Sambommatsu
KSKeita Shimata
Keita Shimata
SISho Ibuki
Sho Ibuki
YNYasuko Narita
Yasuko Narita
KIKaori Isono
Kaori Isono
THTaizo Hibi
Taizo Hibi

27 October 2022 in Cancers
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Journal Article
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Masaki KaiboriMasaki Kaibori
Masaki Kaibori
KYKengo Yoshii
Kengo Yoshii
KMKosuke Matsui
Kosuke Matsui
HMHideyuki Matsushima
Hideyuki Matsushima
HKHisashi Kosaka
Hisashi Kosaka
MSMitsugu Sekimoto
Mitsugu Sekimoto
We developed and evaluated a modified albumin-bilirubin grade and α-fetoprotein (mALF) score, a nutritional and oncological assessment tool for patients with hepatocellular carcinoma (HCC) after surgical resection. Patients (n = 480) who underwent R0 resection between 2010 and 2020 were analyzed retrospectively. The mALF score assigned one point for a modified albumin-bilirubin (mALBI) grade 2b or 3 and one point for an α-fetoprotein (AFP) level ≥ 100 ng/mL. Patients were classified by mALF scores of 0 (mALBI grade 1/2a, AFP < 100 ng/mL), 1 (mALBI grade 2b/3 or AFP ≥ 100 ng/mL), or 2 (mALBI grade 2b/3, AFP ≥ 100 ng/mL) points. Liver reserve deteriorated and cancer progressed with increasing score. Postoperative complications (Clavien–Dindo classification ≥ 3) differed significantly among groups. The 5-year recurrence-free survival (RFS) rates were 34.8%, 11.2%, and 0.0% for 0, 1, and 2 points, respectively (1 or 2 versus 0 points, p < 0.001). The 5-year overall survival (OS) rates were 66.0%, 29.7%, and 17.8% for 0, 1, and 2 points, respectively (1 or 2 versus 0 points, p < 0.001). The mALF score was an independent prognostic predictor of RFS and OS. In HCC, the mALF score was effective for predicting postoperative complications and long-term survival.

9 March 2022 in Cancers
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Journal Article
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Masaki KaiboriMasaki Kaibori
Masaki Kaibori
AHAtsushi Hiraoka
Atsushi Hiraoka
KMKosuke Matsui
Kosuke Matsui
HMHideyuki Matsushima
Hideyuki Matsushima
HKHisashi Kosaka
Hisashi Kosaka
MSMitsugu Sekimoto
Mitsugu Sekimoto
Background/Aim: Nutritional assessment is known to be important for predicting prognosis in patients with malignant diseases. This study examined the usefulness of a prognostic predictive nutritional assessment tool for hepatocellular carcinoma (HCC) patients treated with surgical resection. Materials/Methods: HCC patients (n = 429) classified as Child–Pugh A who underwent an R0 resection between 2010 and 2020 were retrospectively analyzed (median age 73 years, males 326 (76.0%), Child–Pugh score 5:6 = 326:103, single tumor 340 (79.2%), median tumor size 3.5 cm, open:laparoscopic = 304:125). Glasgow prognostic score (GPS) and the newly developed neo-GPS method, which uses albumin–bilirubin grade 1 instead of albumin, were evaluated to compare their usefulness for prognosis prediction. Results: Median survival time for patients with a GPS score of 0, 1, and 2 was 120, 51, and 20 months, respectively. As for neo-GPS, that for those with a score of 0, 1, and 2 was not applicable (NA), 53 months, and 35 months, respectively (each p < 0.001; c-index: 0.556 and 0.611, respectively). Furthermore, median progression-free survival was 33, 22, and 9 months, and 41, 24, and 15 months, respectively (each p < 0.001; c-index: 0.539 and 0.578, respectively). As compared to patients with a high GPS (≥1), those with a high neo-GPS (≥1) showed a greater rate of high Clavien–Dindo classification (≥3) (39.2% vs. 65.1%). A comparison of patients with a high GPS (≥1) with those with a high neo-GPS (≥1) showed no significant difference regarding frequency of open or laparoscopic hepatectomy (17.4% vs. 15.2%, p = 0.670; 44.7% vs. 43.2%, p = 0.831, respectively), while the frequency of high Clavien–Dindo classification (≥3) was lower in patients who underwent a laparoscopic hepatectomy (11.2% vs. 22.7%, p = 0.007). Conclusion: The present findings suggest that the newly developed neo-GPS based on ALBI grade is an effective prognostic nutritional assessment tool and can be used for prediction of postoperative complications.

1 April 2013 in Experimental and Clinical Transplantation
Verified
Journal Article
Closed access
TTTakayuki Takeichi
Takayuki Takeichi
KAKatsuhiro Asonuma
Katsuhiro Asonuma
HYHidekazu Yamamoto
Hidekazu Yamamoto
YOYuki Ohya
Yuki Ohya
KOKenji Okumura
Kenji Okumura
YIYukihiro Inomata
Yukihiro Inomata
Familial amyloid polyneuropathy is a rare, progressively disabling, and ultimately fatal inherited disease. Liver transplant is currently the only available treatment proven to halt the progression of familial amyloid polyneuropathy. We report a 31-year-old woman with familial amyloid polyneuropathy who received a living-donor liver transplant from her husband who was hepatitis C virus antibody-positive but HCV-RNA negative and ABO incompatible. Six years after the transplant, both donor and recipient have normal liver biochemistry results; no hepatitis C viral load has been detectable in the recipient. This is the first report of a living ABO-incompatible liver transplant from an anti-hepatitis C virus antibody-positive but an HCV-RNA negative donor. This experience suggests that the use of an anti-hepatitis C virus antibody-positive hepatic graft is possible in select circumstances.