Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Tsutomu Minamino is active.

Publication


Featured researches published by Tsutomu Minamino.


European Journal of Gastroenterology & Hepatology | 2013

Early increase in α-fetoprotein for predicting unfavorable clinical outcomes in patients with advanced hepatocellular carcinoma treated with sorafenib.

Takahide Nakazawa; Hisashi Hidaka; Juichi Takada; Yusuke Okuwaki; Yoshiaki Tanaka; Masaaki Watanabe; Akitaka Shibuya; Tsutomu Minamino; Shigehiro Kokubu; Wasaburo Koizumi

Background To determine the value of early alterations of the tumor markers &agr;-fetoprotein (AFP) and des-&ggr;-carboxy prothrombin (DCP) for predicting the outcomes of patients with advanced hepatocellular carcinoma (HCC) who receive sorafenib. Materials and methods Tumor response, overall survival (OS), and progression-free survival (PFS) were retrospectively analyzed in 59 patients with advanced HCC. Serum AFP and DCP were examined for early elevation within 4 weeks after the initiation of sorafenib. An increase in AFP was defined as AFP of more than 20%, and an increase in DCP was defined as more than two-fold higher level than the baseline. The relationship of the clinical characteristics, laboratory data at baseline, and early elevations of AFP and DCP with disease progression was analyzed. Results The median OS and PFS were 11 and 3.3 months, respectively. The rate of progressive disease (PD) was 54%, and an early increase in AFP was significantly related to PD (P=0.006) and was a significant independent predictor of both poorer OS and PFS (P<0.001, hazard ratio, 4.14; 95% confidence interval, 1.946–8.811; and P=0.001, hazard ratio, 2.852; 95% confidence interval, 1.524–5.337, respectively). There was no association between early increase in DCP and clinical outcomes. Conclusion Early increase in AFP predicted PD and poorer survival and may thus be a useful biomarker in patients with advanced HCC who receive sorafenib.


Toxicological Sciences | 2011

Vascular endothelial growth factor receptor-1 signaling promotes liver repair through restoration of liver microvasculature after acetaminophen hepatotoxicity

Tetsuki Kato; Yoshiya Ito; Kanako Hosono; Tatsunori Suzuki; Hideaki Tamaki; Tsutomu Minamino; Shintaro Kato; Hiroyuki Sakagami; Masataka Majima

Vascular endothelial growth factor (VEGF) and its receptors promote liver regeneration. The objective of the present study was to examine the role of VEGF receptor 1 (VEGFR1) signaling in hepatic tissue repair after acetaminophen (N-acetyl-para-aminophenol) (APAP)-induced liver injury. To do this, we treated VEGFR1 tyrosine kinase knockout (VEGFR1 TK(-/-)) and wild-type (WT) mice with APAP (300 mg/kg, ip). In WT mice, serum levels of alanine aminotransferase (ALT) and the necrotic area peaked between 8 and 24 h and then declined. In VEGFR1 TK(-/-) mice, ALT levels remained high at 48 h and extensive hepatic necrosis and hemorrhage were observed, as well as high mortality. Downregulation of hepatic messenger RNA expression of VEGFR1 and VEGFR2 was also noted in VEGFR1 TK(-/-) mice. VEGFR1 TK(-/-) mice displayed lower expression of proliferating cell nuclear antigen and of growth factors including hepatocyte growth factor, CD31, and basic fibroblast growth factor than WT. The hepatic microvasculature in VEGFR1 TK(-/-) was compromised as evidenced by impaired sinusoidal perfusion, suppressed endocytosis in liver sinusoidal endothelial cells (LSECs), and the formation of large gaps in LSECs. In WT mice, immunofluorescence revealed that recruited VEGFR1(+) cells in the necrotic area were positive for CD11b. VEGFR1 TK(-/-) exhibited fewer VEGFR1(+) and VEGFR2(+) cells. These results suggest that VEGFR1 signaling facilitates liver recovery from APAP hepatotoxicity by preventing excessive hemorrhage and reconstituting the sinusoids through recruitment of VEGFR1-expressing macrophages to the injured area and also through affecting expression of genes including hepatotrophic and pro-angiogenic growth factors.


European Journal of Internal Medicine | 2010

Entecavir is an optional agent to prevent hepatitis B virus (HBV) reactivation: A review of 16 patients

Masaaki Watanabe; Akitaka Shibuya; Juichi Takada; Yoshiaki Tanaka; Yusuke Okuwaki; Tsutomu Minamino; Hisashi Hidaka; Takahide Nakazawa; Wasaburo Koizumi

BACKGROUND Hepatitis B virus (HBV) reactivation is a fatal complication in patients who receive chemotherapy or immunosuppressive therapy. We examined the effect of preventive entecavir (ETV), a new nucleoside analogue on HBV reactivation during chemotherapy or immunosuppressive therapy. METHODS Between February 2007 and September 2009, sixteen nucleoside analogue treatment-naive patients with chronic HBV infection (HB surface antigen [HBsAg] positive) who required chemotherapy or immunosuppressive therapy were enrolled. Referring to some guidelines, the patients received preventive ETV to reduce incidence of HBV reactivation, and were closely monitored for HBV markers. RESULTS HBV reactivation did not occur in any of the 16 patients and the indispensable treatments for their underlying diseases could be continued. However, HBV relapsed after preventive ETV was discontinued in 2 patients. CONCLUSIONS This study suggests that ETV is a useful option for preventing HBV reactivation in patients with chronic HBV infection.


The American Journal of Gastroenterology | 2009

Repeat Radiofrequency Ablation Provides Survival Benefit in Patients With Intrahepatic Distant Recurrence of Hepatocellular Carcinoma

Yusuke Okuwaki; Takahide Nakazawa; Shigehiro Kokubu; Hisashi Hidaka; Yoshiaki Tanaka; Juichi Takada; Masaaki Watanabe; Akitaka Shibuya; Tsutomu Minamino; Katsunori Saigenji

OBJECTIVES:Intrahepatic distant recurrence (IDR) of hepatocellular carcinoma (HCC) after curative treatment occurs frequently and influences the prognoses. The aim of this study was to determine prognostic factors affecting survival after IDR and the optimum therapy for IDR.METHODS:A total of 115 patients with a single small primary HCC who had complete radiofrequency (RF) ablation were enrolled in this study. The prognostic factors and the optimum therapy affecting survival were statistically analyzed among patients with IDRs.RESULTS:IDRs were observed in 59 (51.3%) patients with the median observation period of 19.6 months. The cumulative rates of IDRs were 11.8, 53.9, and 75.8% at 1, 3, and 5 years, respectively. IDR nodules were present as a single nodule in 38 patients and as multiple nodules in 21 patients. In all, 23 patients died during the follow-up. A total of 30 patients were treated with RF ablation, and 27 were treated with transcatheter arterial chemoembolization (TACE). The overall cumulative survival rates after IDRs were 92.7, 55.4, and 43.7% at 1, 3, and 5 years, respectively. A multivariate analysis showed that treatment with RF ablation for IDR was a significant favorable prognostic factor after IDR (hazard ratio: 0.167, 95% confidence interval: 0.048−0.584, P=0.005). In a comparison of survival after IDR between patients treated with RF ablation and TACE, who were comparable with clinical and tumoral characteristics, the cumulative survival rate of patients treated with RF ablation was significantly higher than that of those treated with TACE (77.2 vs 28.5% at 3 years). The cumulative survival rates obtained from the initial RF ablation of the patients with IDRs treated with repeat RF ablation were similar to those of recurrence-free patients.CONCLUSIONS:Repeat RF ablation should be attempted for IDR as much as possible despite tumor multiplicity for survival benefit; by reducing the need, it will help solve the problem of the current shortage of donors for liver transplantations.


PLOS ONE | 2014

VEGFR1-positive macrophages facilitate liver repair and sinusoidal reconstruction after hepatic ischemia/reperfusion injury.

Hirotoki Ohkubo; Yoshiya Ito; Tsutomu Minamino; Koji Eshima; Ken Kojo; Shin-ichiro Okizaki; Mitsuhiro Hirata; Masabumi Shibuya; Masahiko Watanabe; Masataka Majima

Liver repair after acute liver injury is characterized by hepatocyte proliferation, removal of necrotic tissue, and restoration of hepatocellular and hepatic microvascular architecture. Macrophage recruitment is essential for liver tissue repair and recovery from injury; however, the underlying mechanisms are unclear. Signaling through vascular endothelial growth factor receptor 1 (VEGFR1) is suggested to play a role in macrophage migration and angiogenesis. The aim of the present study was to examine the role of VEGFR1 in liver repair and sinusoidal reconstruction after hepatic ischemia/reperfusion (I/R). VEGFR1 tyrosine kinase knockout mice (VEGFR1 TK-/- mice) and wild-type (WT) mice were subjected to hepatic warm I/R, and the processes of liver repair and sinusoidal reconstruction were examined. Compared with WT mice, VEGFR1 TK-/- mice exhibited delayed liver repair after hepatic I/R. VEGFR1-expressing macrophages recruited to the injured liver showed reduced expression of epidermal growth factor (EGF). VEGFR1 TK-/- mice also showed evidence of sustained sinusoidal functional and structural damage, and reduced expression of pro-angiogenic factors. Treatment of VEGFR1 TK-/- mice with EGF attenuated hepatoceullar and sinusoidal injury during hepatic I/R. VEGFR1 TK-/- bone marrow (BM) chimeric mice showed impaired liver repair and sinusoidal reconstruction, and reduced recruitment of VEGFR1-expressing macrophages to the injured liver. VEGFR1-macrophages recruited to the liver during hepatic I/R contribute to liver repair and sinusoidal reconstruction. VEGFR1 activation is a potential therapeutic strategy for promoting liver repair and sinusoidal restoration after acute liver injury.


American Journal of Physiology-gastrointestinal and Liver Physiology | 2010

Role of microsomal prostaglandin E synthase-1 in the facilitation of angiogenesis and the healing of gastric ulcers

Takako Ae; Takashi Ohno; Youichiro Hattori; Tatsunori Suzuki; Kanako Hosono; Tsutomu Minamino; Takehito Sato; Satoshi Uematsu; Shizuo Akira; Wasaburo Koizumi; Masataka Majima

The importance of prostaglandin E(2) in various pathophysiological events emphasizes the necessity of understanding the role of PGE synthases (PGESs) in vivo. However, there has been no report on the functional relevance of microsomal PGES-1 (mPGES-1) to the physiological healing processes of gastric ulcers, or to angiogenesis, which is indispensable to the healing processes. In this report, we tested whether mPGES-1 plays a role in the healing of gastric ulcers and in the enhancement of angiogenesis using mPGES-1 knockout mice (mPGES-1 KO mice) and their wild-type (WT) counterparts. Gastric ulcers were induced by the serosal application of 100% acetic acid, and the areas of the ulcers were measured thereafter. mPGES-1 together with cyclooxygenase-2 were induced in the granulation tissues compared with normal stomach tissues. The healing of acetic acid-induced ulcers was significantly delayed in mPGES-1 KO mice compared with WT. This was accompanied with reduced angiogenesis in ulcer granulation tissues, as estimated by CD31 mRNA levels determined by real-time PCR and the microvessel density in granulation tissues. The mRNA levels of proangiogenic growth factors, such as transforming growth factor-β, basic fibroblast growth factor, and connective tissue growth factor in ulcer granulation tissues determined were reduced in mPGES-1 KO mice compared with WT. The present results suggest that mPGES-1 enhances the ulcer-healing processes and the angiogenesis indispensable to ulcer healing, and that a selective mPGES-1 inhibitor should be used with care in patients with gastric ulcers.


Liver International | 2011

Re-appearance of hepatitis B virus following therapy with rituximab for lymphoma is not rare in Japanese patients with past hepatitis B virus infection.

Masaaki Watanabe; Akitaka Shibuya; Yuhko Tsunoda; Mikio Danbara; Ryuji Ishii; Manabu Ohsaka; Juichi Takada; Yoshiaki Tanaka; Yusuke Okuwaki; Tsutomu Minamino; Hisashi Hidaka; Takahide Nakazawa; Ryouichi Horie; Masaaki Higashihara; Wasaburo Koizumi

Background and aim: De novo hepatitis B virus (HBV)‐related hepatitis is a well‐known fatal complication following chemo‐immunosuppressive therapy in patients with past HBV infection (HB surface antigen and serum HBV DNA negative, but HB core antibody and/or HB surface antibody positive). This research was conducted to evaluate the incidence of and clinical features associated with re‐appearance of serum HBV DNA following chemo‐immunosuppressive therapy in Japanese patients with past HBV infection.


Toxicology and Applied Pharmacology | 2012

Thromboxane A(2) receptor signaling promotes liver tissue repair after toxic injury through the enhancement of macrophage recruitment.

Tsutomu Minamino; Yoshiya Ito; Hirotoki Ohkubo; Kanako Hosono; Tatsunori Suzuki; Takehito Sato; Takako Ae; Akitaka Shibuya; Hiroyuki Sakagami; Shuh Narumiya; Wasaburo Koizumi; Masataka Majima

It is thought that thromboxane A(2) (TxA(2)) contributes to the progression of inflammation during acute hepatic injury; however, it is still unknown whether TxA(2) is involved in liver repair. The objective of the present study was to examine the role of TxA(2) receptor (TP) signaling in liver injury and repair in response to toxic injury. Carbon tetrachloride (CCl(4)) was used to induce liver injury in TP knockout (TP(-/-)) mice and wild-type (WT) mice. In WT mice, serum levels of alanine aminotransferase (ALT) and the size of the necrotic area peaked at 24 and 48h, respectively, and then declined. In TP(-/-) mice, the changes in ALT levels were similar to WT mice, but liver regeneration was impaired as evidenced by remained elevated levels of hepatic necrosis and by delayed hepatocyte proliferation, which was associated with the reduced expression of growth factors including interleukin-6 (IL-6), tumor necrosis factor alpha (TNFα), and hepatocyte growth factor (HGF). In TP(-/-) mice, the accumulation of hepatic CD11b(+)/F4/80(+) macrophages in injured livers was attenuated, and the hepatic expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and its receptor, the C-C chemokine receptor (CCR2), was reduced compared to WT. Additionally, the application of the TP receptor agonist, U-46619, enhanced the expression of MCP-1/CCL2 and CCR2 in peritoneal macrophages, which was associated with increased levels of IL-6, TNFα and HGF. These results suggested that TP receptor signaling facilitates liver recovery following CCl(4)-induced hepatotoxicity by affecting the expression of hepatotrophic growth factors, and through the recruitment of macrophages mediated by MCP-1/CCL2-CCR2 expression.


American Journal of Physiology-gastrointestinal and Liver Physiology | 2010

Roles of prostaglandin E2-EP1 receptor signaling in regulation of gastric motor activity and emptying

Sumito Mizuguchi; Takashi Ohno; Youichiro Hattori; Takako Ae; Tsutomu Minamino; Takehito Satoh; Katsuharu Arai; Takeo Saeki; Izumi Hayashi; Yukihiko Sugimoto; Shuh Narumiya; Katsunori Saigenji; Masataka Majima

It is widely accepted that the inhibition of gastric motor activity as well as the maintenance of gastric mucosal blood flow and mucous secretion are important for the homeostasis of the gastric mucosa. The present study was performed to ascertain whether or not endogenous PGs, which can protect the stomach from noxious stimuli, affect gastric motor activity and emptying. The myoelectrical activity of rat gastric smooth muscle was increased at intragastric pressures of over 2 cmH(2)O. Replacement of intragastric physiological saline with 1 M NaCl solution significantly increased PGI(2) and PGE(2) in stomach and suppressed the myoelectrical activity under a pressure of 2 cmH(2)O by 70%. Indomethacin inhibited the suppression of myoelectrical activity by 1 M NaCl. The myoelectrical activity under a pressure of 2 cmH(2)O was suppressed by continuous infusion of a selective EP1 agonist (ONO-DI-004, 3-100 nmol·kg(-1)·min(-1)) into the gastric artery in a dose-dependent manner, but not by that of the PGI receptor agonist beraprost sodium (100 nmol·kg(-1)·min(-1)). Suppression of myoelectrical activity with 1 M NaCl was inhibited by continuous infusion of a selective EP1 antagonist (ONO-8711, 100 nmol·kg(-1)·min(-1)) into the gastric artery. Furthermore, gastric emptying was tested in EP1 knockout mice and their wild-type counterparts. Gastric emptying was strongly suppressed with intragastric 1 M NaCl in wild-type mice, but this 1 M NaCl-induced suppression was not seen in EP1 knockout mice. These results suggest that PGE(2)-EP1 signaling has crucial roles in suppression of myoelectrical activity of gastric smooth muscles and inhibition of gastric emptying and that EP1 is an obvious target for drugs that control gastric emptying.


Journal of Gastroenterology and Hepatology | 2014

Radiotherapy for patients with unresectable advanced hepatocellular carcinoma with invasion to intrahepatic large vessels: Efficacy and outcomes

Yoshiaki Tanaka; Takahide Nakazawa; Shouko Komori; Hisashi Hidaka; Yusuke Okuwaki; Juichi Takada; Masaaki Watanabe; Akitaka Shibuya; Tsutomu Minamino; Hajime Yamamoto; Shigehiro Kokubu; Kazushige Hayakawa; Wasaburo Koizumi

To examine the efficacy and outcomes of radiotherapy (RT) in patients who have hepatocellular carcinoma with invasion to intrahepatic large vessels (IHLVs).

Collaboration


Dive into the Tsutomu Minamino's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge