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Featured researches published by Kentaro Ushijima.


American Journal of Transplantation | 2010

Living Donor Liver Transplantation for Neonates Using Segment 2 Monosubsegment Graft

Koichi Mizuta; Yoshikazu Yasuda; Satoshi Egami; Yukihiro Sanada; Taiichi Wakiya; Taizen Urahashi; Minoru Umehara; Shuji Hishikawa; Makoto Hayashida; Masanobu Hyodo; Yasunaru Sakuma; Takehito Fujiwara; Kentaro Ushijima; Koichi Sakamoto; Hideo Kawarasaki

The prognosis of liver transplantation for neonates with fulminant hepatic failure (FHF) continues to be extremely poor, especially in patients whose body weight is less than 3 kg. To address this problem, we have developed a safe living donor liver transplantation (LDLT) modality for neonates. We performed LDLTs with segment 2 monosubsegment (S2) grafts for three neonatal FHF. The recipient age and body weight at LDLT were 13–27 days, 2.59–2.84 kg, respectively. S2 or reduced S2 grafts (93–98 g) obtained from their fathers were implanted using temporary portacaval shunt. The recipient portal vein was reconstructed at a more distal site, such as the umbilical portion, to have the graft liver move freely during hepatic artery (HA) reconstruction. The recipient operation time and bleeding were 11 h 58 min–15 h 27 min and 200–395 mL, respectively. The graft‐to‐recipient weight ratio was 3.3–3.8% and primary abdominal wall closure was possible in all cases. Although hepatic artery thrombosis occurred in one case, all cases survived with normal growth. Emergency LDLT with S2 grafts weighing less than 100 g can save neonates with FHF whose body weight is less than 3 kg. This LDLT modality using S2 grafts could become a new option for neonates and very small infants requiring LT.


Transplantation Proceedings | 2010

Living-Donor Liver Transplantation in 126 Patients with Biliary Atresia: Single-Center Experience

Koichi Mizuta; Yukihiro Sanada; Taiichi Wakiya; Taizen Urahashi; Minoru Umehara; Satoshi Egami; Shuji Hishikawa; Noriki Okada; Youichi Kawano; T. Saito; Makoto Hayashida; S. Takahashi; H Yoshino; A. Shimizu; Y. Takatsuka; T. Kitamura; Y. Kita; T. Uno; Y. Yoshida; Masanobu Hyodo; Yasunaru Sakuma; Takehito Fujiwara; Kentaro Ushijima; K. Sugimoto; Masami Ohmori; S. Ohtomo; Koichi Sakamoto; Manabu Nakata; Tomonori Yano; Hironori Yamamoto

OBJECTIVES To describe our experience with 126 consecutive living-donor liver transplantation (LDLT) procedures performed because of biliary atresia and to evaluate the optimal timing of the operation. PATIENTS AND METHODS Between May 2001 and January 2010,126 patients with biliary atresia underwent 130 LDLT procedures. Mean (SD) patient age was 3.3 (4.2) years, and body weight was 13.8 (10.7) kg. Donors included 64 fathers, 63 mothers, and 3 other individuals. The left lateral segment was the most commonly used graft (75%). Patients were divided into 3 groups according to body weight: group 1, less than 8 kg (n = 40); group 2,8 to 20 kg (n = 63); and group 3, more than 20 kg (n = 23). Medical records were reviewed retrospectively. Follow up was 4.5 (2.7) years. RESULTS All group 3 donors underwent left lobectomy, and all group 1 donors underwent left lateral segmentectomy. No donors required a second operation or died. Comparison of the 3 groups demonstrated that recipient Pediatric End-Stage Liver Disease score in group 1 was highest, operative blood loss in group 2 was lowest (78 mL/kg), and operative time in group 3 was longest (1201 minutes). Hepatic artery complications occurred more frequently in group 1 (17.9%), and biliary stenosis (43.5%) and gastrointestinal perforation (8.7%) occurred more frequently in group 3. The overall patient survival rates at 1, 5, and 9 years was 98%, 97%, and 97%, respectively. Five-year patient survival rate in groups 1,2, and 3 were 92.5%, 100%, and 95.7%, respectively. Gastrointestinal perforation (n = 2) was the primary cause of death. CONCLUSIONS Living-donor liver transplantation is an effective treatment of biliary atresia, with good long-term outcome. It seems that the most suitable time to perform LDLT to treat biliary atresia is when the patient weighs 8 to 20 kg.


Surgery | 2012

The role of operative intervention in management of congenital extrahepatic portosystemic shunt

Yukihiro Sanada; Taizen Urahashi; Yoshiyuki Ihara; Taiichi Wakiya; Noriki Okada; Naoya Yamada; Satoshi Egami; Shuji Hishikawa; Youichi Kawano; Kentaro Ushijima; Shinya Otomo; Koichi Sakamoto; Manabu Nakata; Yoshikazu Yasuda; Koichi Mizuta

BACKGROUND AND AIMS Congenital extrahepatic portosystemic shunt (CEPS) is a rare venous malformation in which mesenteric venous blood drains directly into the systemic circulation. It is still a matter of debate whether conservative or operative strategies should be used to treat symptomatic CEPS. The aim of this study was to evaluate the role of operative intervention in the management of CEPS. METHODS Between June 2004 and August 2010, 6 consecutive patients with symptomatic CEPS were treated in our department. There were 3 male and 3 female patients, with a median age of 3.5 years (range, 1-8). Their demographic, clinical, and laboratory data were analyzed. All patients were scheduled to undergo shunt ligation or liver transplantation (LT). RESULTS Living donor LT was carried out in 4 patients, and shunt ligation in 2. After a median follow-up of 25 months, all the patients are alive currently with marked relief of symptoms. CONCLUSION Shunt ligation or LT for symptomatic CEPS is potentially curative.


Endocrinology | 2016

Daily Fasting Blood Glucose Rhythm in Male Mice: A Role of the Circadian Clock in the Liver.

Hitoshi Ando; Kentaro Ushijima; Shigeki Shimba; Akio Fujimura

Fasting blood glucose (FBG) and hepatic glucose production are regulated according to a circadian rhythm. An early morning increase in FBG levels, which is pronounced among diabetic patients, is known as the dawn phenomenon. Although the intracellular circadian clock generates various molecular rhythms, whether the hepatic clock is involved in FBG rhythm remains unclear. To address this issue, we investigated the effects of phase shift and disruption of the hepatic clock on the FBG rhythm. In both C57BL/6J and diabetic ob/ob mice, FBG exhibited significant daily rhythms with a peak at the beginning of the dark phase. Light-phase restricted feeding altered the phase of FBG rhythm mildly in C57BL/6J mice and greatly in ob/ob mice, in concert with the phase shifts of mRNA expression rhythms of the clock and glucose production-related genes in the liver. Moreover, the rhythmicity of FBG and Glut2 expression was not detected in liver-specific Bmal1-deficient mice. Furthermore, treatment with octreotide suppressed the plasma growth hormone concentration but did not affect the hepatic mRNA expression of the clock genes or the rise in FBG during the latter half of the resting phase in C57BL/6J mice. These results suggest that the hepatic circadian clock plays a critical role in regulating the daily FBG rhythm, including the dawn phenomenon.


Pharmacology Research & Perspectives | 2017

Prevention against renal damage in rats with subtotal nephrectomy by sacubitril/valsartan (LCZ696), a dual-acting angiotensin receptor-neprilysin inhibitor

Kentaro Ushijima; Hitoshi Ando; Yusuke Arakawa; Kenichi Aizawa; Chisato Suzuki; Ken Shimada; Shuichi Tsuruoka; Akio Fujimura

Although patients with chronic kidney disease (CKD) are at increased risk for end‐stage renal disease and cardiovascular events, adequate drug therapies for preventing the deterioration of these conditions are still not established. This study was undertaken to evaluate a preventive effect of an angiotensin receptor‐neprilysin inhibitor sacubitril/valsartan (LCZ696), which is converted to sacubitril and valsartan in the body, against the progression of renal disease in rats with subtotal nephrectomy, an animal model of human CKD. Mean survival time after subtotal nephrectomy was about 100 days in Wistar rats with vehicle. LCZ696‐(30 mg/kg) and valsartan‐(15 mg/kg) prolonged the survival of these animals, and the effect of LCZ696 on survival was significantly greater than that of valsartan. Renoprotective effects of LCZ696 judged by serum creatinine and urinary protein excretions were larger than those of valsartan. Cardioprotective effects judged by cardiac left ventricular mass, fractional shortening, and fibrosis of LCZ696 and valsartan were not detected under the present condition. Thus, the renoprotective effect of LCZ696 was stronger than that of valsartan in rats with subtotal nephrectomy. This study provides the idea that, compared to valsartan, LCZ696 is more effective for the treatment of human CKD.


Molecular Genetics and Metabolism | 2012

Impact of enzyme activity assay on indication in liver transplantation for ornithine transcarbamylase deficiency.

Taiichi Wakiya; Yukihiro Sanada; Taizen Urahashi; Yoshiyuki Ihara; Naoya Yamada; Noriki Okada; Kentaro Ushijima; Shinya Otomo; Koichi Sakamoto; Kei Murayama; Masaki Takayanagi; Kenichi Hakamada; Yoshikazu Yasuda; Koichi Mizuta

There are no objective and concrete guidelines for the management of Ornithine transcarbamylase deficiency (OTCD). Based on previous findings, we hypothesized that patients with OTCD have a low Ornithine transcarbamylase (OTC) activity in the liver, and therefore it would be better to determine the appropriate indications and optimal timing for liver transplantation (LT) based on the OTC activity. However, few data have so far been accumulated on the OTC activity in cases that are indicated for LT. The purpose of the present study was to clarify the OTC activity in cases that were indicated for LT. This study involved thirteen children with OTCD (8 males and 5 females) who underwent LT, and two females with OTCD who did not require LT. The OTC activity of the neonatal onset type ranged from 0% to 7.2%, while that of the late onset type who underwent LT ranged from 4.4% to 18.7%. The OTC activity of the late onset type which did not require LT was 33-38% based on a preoperative needle liver biopsy. Some late onset patients that underwent LT, showed an activity that was as low as that observed in the neonatal onset cases. This is the first report to show the results of measuring the OTC activity for serial OTCD cases indicated for LT. OTC activity might be an indicator to determine the indications for and the timing of LT in the late onset type, however, further investigations are necessary.


Modern Rheumatology | 2017

Prediction of the therapeutic response to methotrexate at 24 weeks by methotrexate–polyglutamates concentration in erythrocytes at 8 weeks in patients with rheumatoid arthritis

Takamasa Murosaki; Katsuya Nagatani; Takeo Sato; Yoichiro Akiyama; Kentaro Ushijima; Alan Kawarai Lefor; Akio Fujimura; Seiji Minota

Abstract Objectives: The objective of this study is to evaluate the pharmacokinetics and pharmacodynamics of methotrexate–polyglutamates (MTX-PGs) in erythrocytes in patients with rheumatoid arthritis and correlate them with the efficacy. Methods: MTX-PG concentrations in erythrocytes were measured in 42 MTX-naïve patients repeatedly for 24 weeks by high-performance liquid chromatography. In 56 patients receiving stable MTX doses for at least 12 weeks, the correlation between MTX doses and MTX-PG concentrations was examined. The efficacy was measured by the change of DAS28CRP (ΔDAS28CRP). Results: There were moderate correlations between MTX dose and MTX-PG 3, 4, and 5. At 24 weeks, MTX-PG2, 3, 4, and 1–5 were higher in patients with ΔDAS28CRP >1.2 than in those with ≤1.2. The cutoff value of MTX-PG1-5 to discriminate ΔDAS28CRP >1.2 from ≤1.2 at 24 weeks was 68.7 nM. Among 20 patients with MTX-PG1-5 > 50.6 nM at 8 weeks, seven already improved at 8 weeks and additional 11 improved at 24 weeks (p < 0.001). On the contrary, among the nine patients with MTX-PG1-5 ≤ 50.6 nM at 8 weeks, none improved at 8 weeks and only one improved at 24 weeks (p = 0.500). Conclusions: Erythrocyte MTX-PGs might be a potential indicator and predictor of MTX efficacy.


Journal of Pharmacological Sciences | 2015

Different chronotherapeutic effects of valsartan and olmesartan in non-dipper hypertensive patients during valsartan treatment at morning.

Kentaro Ushijima; Hajime Nakashima; Tsuyoshi Shiga; Kazuhiro Harada; Shizukiyo Ishikawa; Takashi Ioka; Hitoshi Ando; Akio Fujimura

This study was undertaken to evaluate the differences in chronotherapeutic effects of angiotensin-II receptor blockers, valsartan and olmesartan in hypertensive patients with non-dipper blood pressure (BP) pattern during valsartan at morning. Ninety four patients were enrolled, and 40 patients were judged to be non-dippers. In these patients, same dose of valsartan was changed to evening (Val-E, n = 12), or olmesartan (equivalent dose of valsartan) was given at morning (Olm-M, n = 13) or evening (Olm-E, n = 15) for 4 months. BP decreased during sleep and increased during waking hours in Val-E group. In Olm-M and Olm-E groups, BP decreased during sleep and waking hours. Percent reduction in BP at night-time compared to BP at waking hours significantly increased after changing the dose regimen in each group. Serum creatinine decreased and estimated glomerular filtration rate (eGFR) elevated in Olm-M and Olm-E, but not Val-E groups. Positive correlation between systolic BP (SBP) during sleep and serum creatinine, and negative correlation between SBP during sleep and eGFR were detected. These data suggest that dipper BP pattern could be obtained by chronotherapeutic approach using valsartan and olmesartan in non-dipper patients with valsartan at morning. Morning and evening olmesartan, but not evening valsartan improved renal function in these patients.


Journal of Pharmacology and Experimental Therapeutics | 2013

Involvement of Wee1 in the circadian rhythm dependent intestinal damage induced by docetaxel

Yuri Obi-Ioka; Kentaro Ushijima; Mikio Kusama; Eiko Ishikawa-Kobayashi; Akio Fujimura

Docetaxel, a semisynthetic taxane, is effective for the treatment of some solid cancers; however, docetaxel-induced intestinal damage leads to poor prognosis in some patients. Although such adverse effects have been reported to depend on the dosing-time of docetaxel, the mechanisms involved remain unclear. Wee1 expression is controlled by the clock gene complex, clock/bmal1, and contributes to cell-cycle progression. The present study was undertaken to evaluate the potential role of Wee1 in the circadian rhythm–dependent profile of docetaxel. Male mice were maintained under a 12-hour light/dark cycle. Intestinal damage after repeated dosing of docetaxel (20 mg/kg) for 3 weeks was more severe at 14 hours after light on (HALO) than at 2 HALO. The intestinal protein expressions of Wee1, phosphorylated CDK1, and cleaved Caspase-3 were higher in the 14-HALO group than in the 2-HALO group, whereas that of survivin was lower in the 14-HALO group. Thus, it is speculated that elevated Wee1 expression inhibited CDK1 activity more by phosphorylation, which in turn caused the lower expression of survivin and consequently more activated Caspase-3 in the 14-HALO group. There were no significant differences in plasma docetaxel concentrations between the 2- and 14-HALO groups. Bindings of CLOCK and BMAL1 to the E-box regions at the wee1 gene promoter were not altered by docetaxel treatment at 2 and 14 HALO. These findings suggest that Wee1 is directly or indirectly involved in the mechanism of the circadian rhythm–dependent changes in docetaxel-induced intestinal damage. However, the mechanism for a circadian rhythm–dependent change in intestinal Wee1 expression by docetaxel remains to be determined.


Transplantation Proceedings | 2012

Prediction of Acute Cellular Rejection by Peripheral Blood Eosinophilia in Pediatric Living Donor Liver Transplantation

Yukihiro Sanada; Kentaro Ushijima; Koichi Mizuta; Taizen Urahashi; Yoshiyuki Ihara; Taiichi Wakiya; Noriki Okada; Naoya Yamada; Satoshi Egami; Shuji Hishikawa; Shinya Otomo; Koichi Sakamoto; Yoshikazu Yasuda; Hideo Kawarasaki

BACKGROUND Acute cellular rejection (ACR) is a common cause of morbidity following liver transplantation. Several reports have evaluated the predictive value of peripheral blood eosinophilia as a simple noninvasive diagnostic marker for ACR. This study examined whether the relative eosinophil counts (REC) predicted ACR in pediatric living donor liver transplantation (LDLT). METHODS One hundred three patients underwent LDLT between May 2001 and December 2007. ACR were diagnosed based on the pathological findings. RESULTS The incidence of ACR was 46.6% (48/103); ACR was diagnosed an average of 13.5 days after LDLT. The average REC at 4 and 2 days before the onset ACR (n = 39) within 30 postoperative day (POD) was 4.3% and 7.3%, respectively, and 9.0% at the onset. Patients with ACR showed significantly higher levels of REC compared with those free of ACR (P = .039). REC thresholds of 10% at POD 7 displayed a sensitivity and specificity of ACR detection of 80% and 75%, respectively. Moreover, the accumulated morbidity ratio of ACR within 30 POD was significantly higher with REC >10% at POD 7 (P = .007). CONCLUSION ACR within POD 30 should be considered when REC is >10% at POD 7 after LDLT.

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Koichi Mizuta

Jichi Medical University

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Noriki Okada

Jichi Medical University

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Akio Fujimura

Jichi Medical University

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Shinya Otomo

Jichi Medical University

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Naoya Yamada

Jichi Medical University

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Taiichi Wakiya

Jichi Medical University

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