Masashi Hirooka

Dr. Masashi Hirooka

orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

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

Representative Publications

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30 January 2019 in Scientific Reports
Verified
Journal Article
Open access
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YNYoshiko Nakamura
Yoshiko Nakamura
MAMasanori Abe
Masanori Abe
KKKeitarou Kawasaki
Keitarou Kawasaki
TMTeruki Miyake
Teruki Miyake
TWTakao Watanabe
Takao Watanabe
YHYoichi Hiasa
Yoichi Hiasa
Obesity-induced adipose-tissue dysfunction is a critical contributor to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). B cell-activating factor (BAFF) is an adipokine related to impaired insulin sensitivity, and the serum BAFF concentration is associated with NAFLD severity. In this study, we aimed to determine the direct in vivo role of BAFF in the development of insulin resistance, adipocyte dysfunction, and hepatic steatosis using BAFF−/− mice fed a high-fat diet (HFD). HFD-fed BAFF−/− mice exhibited significantly improved insulin sensitivity despite their increased weight gain and adiposity relative to HFD-fed wild-type mice. Moreover, inflammation, especially the accumulation of CD11c+ adipose-tissue macrophages, and fibrosis of epididymal adipose tissue were reduced, contributing to healthy adipose-tissue expansion in obese BAFF−/− mice. In line with metabolically healthy obesity, hepatic steatosis also decreased, and we observed attenuated de novo lipogenesis in both the livers and hepatocytes of BAFF−/− mice. Our data revealed that BAFF serves as a potential stimulator of unhealthy adipose-tissue expansion by triggering inflammation and fibrosis and ultimately leading to enhanced insulin resistance and NAFLD. Therefore, these results suggest that BAFF is a promising target for diabetes and NAFLD treatment.

7 February 2017 in Hepatology Research
Verified
Journal Article
Closed access
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YKYohei Koizumi
Yohei Koizumi
MHMasashi Hirooka
Masashi Hirooka
MAMasanori Abe
Masanori Abe
YTYoshio Tokumoto
Yoshio Tokumoto
OYOsamu Yoshida
Osamu Yoshida
YHYoichi Hiasa
Yoichi Hiasa

31 August 2013 in BMC Gastroenterology
Verified
Journal Article
Open access
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TKTaira Kuroda
Taira Kuroda
TKTeru Kumagi
Teru Kumagi
TYTomoyuki Yokota
Tomoyuki Yokota
HSHirotaka Seike
Hirotaka Seike
MNMari Nishiyama
Mari Nishiyama
MOMorikazu Onji
Morikazu Onji
Although the outcomes of pancreatic cancer have been improved by gemcitabine, the changes in its characteristics and long-term outcomes within the gemcitabine era remain unclear. This study was conducted to identify clinical characteristics of pancreatic cancer patients within the gemcitabine era. A retrospective chart review was performed at 10 centers for 1,248 consecutive patients who were ever considered to have a diagnosis of pancreatic cancer between 2001 and 2010. Data collected included demographics, diagnosis date, clinical stage, treatment, and outcome; 1,082 patients met the inclusion criteria and were analyzed further. The chi-square test, Student’s t-test, and Mann–Whitney U-test were used for statistical analysis. Outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazards regression. Differences in survival analyses were determined using the log-rank test. The distribution of clinical stages was: I, 2.2%; II, 3.4%; III, 13%; IVa, 27%; and IVb, 55%. Chemotherapy alone was administered to 42% of patients and 17% underwent resection. The 1-, 3-, and 5-year survival rates were 39%, 13%, and 6.9%, respectively. The median survival time was 257 days, but differed considerably among treatments and clinical stages. Demographics, distribution of clinical stage, and cause of death did not differ between groups A (2001–2005, n = 406) and B (2006–2010, n = 676). However, group B included more patients who underwent chemotherapy (P < 0.0001) and fewer treated with best supportive care (P = 0.0004), mirroring improvements in this group’s long-term outcomes (P = 0.0063). Finally, factors associated with long-term outcomes derived from multivariate analysis were clinical stage (P < 0.0001), location of the tumor (P = 0.0294) and treatments (surgery, chemotherapy) (P < 0.0001). Long-term outcomes in pancreatic cancer has improved even within the gemcitabine era, suggesting the importance of offering chemotherapy to patients previously only considered for best supportive care. Most patients are still diagnosed at an advanced stage, making clinical strategy development for diagnosing pancreatic cancer at earlier stages essential.

12 March 2009 in Digestive Endoscopy
Verified
Journal Article
Closed access
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MHMasashi Hirooka
Masashi Hirooka
YKYoshiyasu Kisaka
Yoshiyasu Kisaka
TUTakahide Uehara
Takahide Uehara
KIKiyotaka Ishida
Kiyotaka Ishida
TKTeru Kumagi
Teru Kumagi
MOMorikazu Onji
Morikazu Onji

3 March 2022 in Journal of Medical Ultrasonics
Verified
Journal Article
Closed access
PDF file
MHMasashi Hirooka
Masashi Hirooka
YKYohei Koizumi
Yohei Koizumi
KSKotarou Sunago
Kotarou Sunago
YNYoshiko Nakamura
Yoshiko Nakamura
KHKana Hirooka
Kana Hirooka
YHYoichi Hiasa
Yoichi Hiasa

1 August 2009 in American Journal of Roentgenology
Verified
Journal Article
Closed access
MHMasashi Hirooka
Masashi Hirooka
YKYoshiyasu Kisaka
Yoshiyasu Kisaka
KUKazuhiro Uesugi
Kazuhiro Uesugi
YKYohei Koizumi
Yohei Koizumi
MAMasanori Abe
Masanori Abe
MOMorikazu Onji
Morikazu Onji
OBJECTIVE. In this study, we evaluated the feasibility of using a virtual puncture line in 3D CT for the treatment of 21 hepatocellular carcinoma (HCC) nodules in the caudate lobe.CONCLUSION. There were no severe complications in this study. Thus, the treatment of HCC nodules in the caudate lobe using a virtual puncture line is feasible.