Shintaro Yagi
Kyoto University
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American Journal of Transplantation | 2013
Toshimi Kaido; K. Ogawa; Yasuhiro Fujimoto; Yasuhiro Ogura; Koichiro Hata; Tatsuo Ito; Koji Tomiyama; Shintaro Yagi; Akira Mori; Shinji Uemoto
Skeletal muscle depletion, referred to as sarcopenia, predicts morbidity and mortality in patients undergoing digestive surgery. However, the impact on liver transplantation is unclear. The present study investigated the impact of sarcopenia on patients undergoing living donor liver transplantation (LDLT). Sarcopenia was assessed by a body composition analyzer in 124 adult patients undergoing LDLT between February 2008 and April 2012. The correlation of sarcopenia with other patient factors and the impact of sarcopenia on survival after LDLT were analyzed. The median ratio of preoperative skeletal muscle mass was 92% (range, 67–130%) of the standard mass. Preoperative skeletal muscle mass was significantly correlated with the branched‐chain amino acids to tyrosine ratio (r = −0.254, p = 0.005) and body cell mass (r = 0.636, p < 0.001). The overall survival rate in patients with low skeletal muscle mass was significantly lower than in patients with normal/high skeletal muscle mass (p < 0.001). Perioperative nutritional therapy significantly increased overall survival in patients with low skeletal muscle mass (p = 0.009). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for death after transplantation. In conclusion, sarcopenia was closely involved with posttransplant mortality in patients undergoing LDLT. Perioperative nutritional therapy significantly improved overall survival in patients with sarcopenia.
Journal of Clinical Microbiology | 2002
Tatsuji Kimura; Akinori Rokuhara; Yoko Sakamoto; Shintaro Yagi; Eiji Tanaka; Kendo Kiyosawa; Noboru Maki
ABSTRACT A sensitive enzyme immunoassay (EIA) specific for hepatitis B virus core antigen (HBcAg) and hepatitis B e antigen (HBeAg) was developed. We designated the precore/core gene products as hepatitis B virus (HBV) core-related antigens (HBcrAg). In order to detect HBcrAg even in anti-HBc/e antibody-positive specimens, the specimens were pretreated in detergents. The antibodies are inactivated by this pretreatment and, simultaneously, the antigens are released and the epitopes are exposed. The assay demonstrated 71 to 112% recovery using HBcrAg-positive sera. We observed no interference from the tested anticoagulants or blood components. When the cutoff value was tentatively set at 103 U/ml, all healthy control (HBsAg/HBV-DNA negative; n = 108) and anti-HCV antibody-positive (n = 59) sera were identified as negative. The assay showed a detection limit of 4 × 102 U/ml using recombinant antigen. Detection limits were compared in four serially diluted HBV high-titer sera. The HBcrAg assay demonstrated higher sensitivity than HBV-DNA transcription-mediated amplification (TMA) or HBeAg radio immunoassay (RIA) in the dilution test. HBcrAg concentrations correlated well with HBV-DNA TMA (r = 0.91, n = 29) and in-house real-time detection-PCR (r = 0.93, n = 47) in hepatitis B patients. On HBeAg/anti-HBe antibody seroconversion panels, the HBcrAg concentration changed in accordance with HBV-DNA levels. HBcrAg concentration provides a reflection of HBV virus load equivalent to HBV-DNA level, and the assay therefore offers a simple method for monitoring hepatitis B patients.
Transplantation | 2006
Shintaro Yagi; Taku Iida; Tomohide Hori; Kentaro Taniguchi; Chizuru Yamamoto; Kentaro Yamagiwa; Shinji Uemoto
Background. Previous studies have shown poor outcome after living-donor liver transplantation (LDLT) as a result of excessive portal venous pressure (PVP), excessive portal venous flow (PVF), or inadequate PVF. We investigated optimal portal venous circulation for liver graft function after LDLT in adult recipients retrospectively. Methods. Between June 2003 and November 2004, 28 adult patients underwent LDLT in our institution. We modulated PVP under 20 mmHg in these 28 cases by performing a splenectomy (n=4) or splenorenal shunt (n=1). The PVF and PVP were measured at the end of the operation. Compliance was calculated by dividing PVF by PVP. Results. PVF and compliance showed a significant inverse correlation with peak billirubin levels after LDLT (r = -0.63: r=−0.60, P<0.01), and with peak international normalized ratio after LDLT (r=−0.41: r=−0.51, P<0.05). Compliance was higher in right-lobe graft with middle hepatic vein cases (148±27 ml/min/mmHg), and lower in left-lobe graft cases (119±50 ml/min/mmHg). Conclusions. Liver graft function was better when PVF and graft compliance were higher and PVP was maintained under 20 mmHg.
Hepatology | 2009
Hiromitsu Nagata; Etsuro Hatano; Masaharu Tada; Miki Murata; Koji Kitamura; Hiroyuki Asechi; Masato Narita; Atsuko Yanagida; Nobuyuki Tamaki; Shintaro Yagi; Iwao Ikai; Koichi Matsuzaki; Shinji Uemoto
Transforming growth factor beta (TGF‐β) signaling involves both tumor‐suppression and oncogenesis. TGF‐β activates the TGF‐β type I receptor (TβRI) and c‐Jun N‐terminal kinase (JNK), which differentially phosphorylate the mediator Smad3 to become COOH‐terminally phosphorylated Smad3 (pSmad3C) and linker‐phosphorylated Smad3 (pSmad3L). TβRI‐dependent pSmad3C transmits a tumor‐suppressive TGF‐β signal, while JNK‐dependent pSmad3L promotes carcinogenesis in human chronic liver disorders. The aim of this study is to elucidate how SP600125, a JNK inhibitor, affected rat hepatocellular carcinoma (HCC) development, while focusing on the domain‐specific phosphorylation of Smad3. The rats received subcutaneous injections of either SP600125 or vehicle 11 times weekly together with 100 ppm N‐diethylnitrosamine (DEN) administration for 56 days and were sacrificed in order to evaluate HCC development 28 days after the last DEN administration. The number of tumor nodules greater than 3 mm in diameter and the liver weight/body weight ratio were significantly lower in the SP600125‐treated rats than those in the vehicle‐treated rats (7.9 ± 0.8 versus 17.7 ± 0.9: P < 0.001; 6.3 ± 1.2 versus 7.1 ± 0.2%: P < 0.05). SP600125 significantly prolonged the median survival time in rats with DEN‐induced HCC (113 versus 97 days: log‐rank P = 0.0018). JNK/pSmad3L/c‐Myc was enhanced in the rat hepatocytes exposed to DEN. However, TβRI/pSmad3C/p21WAF1 was impaired as DEN‐induced HCC developed and progressed. The specific inhibition of JNK activity by SP600125 suppressed pSmad3L/c‐Myc in the damaged hepatocytes and enhanced pSmad3C/p21WAF1, acting as a tumor suppressor in normal hepatocytes. Conclusion: Administration of SP600125 to DEN‐treated rats shifted hepatocytic Smad3‐mediated signal from oncogenesis to tumor suppression, thus suggesting that JNK could be a therapeutic target of human HCC development and progression. (HEPATOLOGY 2009.)
Liver Transplantation | 2010
Taku Iida; Toshimi Kaido; Shintaro Yagi; Atsushi Yoshizawa; Koichiro Hata; Masaki Mizumoto; Akira Mori; Yasuhiro Ogura; Fumitaka Oike; Shinji Uemoto
Infectious complications such as bacteremia after living donor liver transplantation (LDLT) are associated with significant morbidity and mortality. We retrospectively analyzed the frequency and characteristics of posttransplant bacteremia in 181 adult LDLT recipients between April 2006 and November 2009, and we evaluated the risk factors for posttransplant bacteremia. One hundred seventeen episodes of bacteremia occurred in 62 of 181 recipients (34.3%) within 12 days (median) after transplantation (range = 1‐71 days). The most frequently isolated pathogens were Pseudomonasaeruginosa (26 episodes), methicillin‐resistant coagulase‐negative staphylococci (22 episodes), and Enterococcus sp. (11 episodes). The overall survival rate at 1 year for patients with bacteremia (n = 62) was significantly lower than the rate for patients without bacteremia (n = 119; 69.6% versus 92.3%, respectively, P < 0.0001). Multivariate analysis showed that Child‐Pugh class C (P = 0.0002), preoperative massive pleural effusion or ascites requiring drainage (P = 0.0384), postoperative cytomegalovirus infection (P = 0.0014), ABO incompatibility (P = 0.0188), and older donor age (P = 0.015) were independent risk factors for postoperative bacteremia. In conclusion, bacteremia occurred at a high rate after adult LDLT and induced a higher mortality rate in those who developed it. Infection control may play a pivotal role in improving early outcomes after LDLT. Liver Transpl 16:1379–1385, 2010.
Transplantation Proceedings | 2011
Toshimi Kaido; Akira Mori; Yasuhiro Ogura; Koichiro Hata; Akihiko Yoshizawa; Taku Iida; Shintaro Yagi; Shinji Uemoto
INTRODUCTION The goal of this study was to examine whether the lower limit of the graft-to-recipient weight ratio (GRWR) can be safely reduced to make better use of a left-lobe graft in adult-to-adult living donor liver transplantation (LDLT) in combination with portal pressure control. PATIENTS AND METHODS Beginning in December 2007, our institution actively selected left-lobe grafts for use in liver transplantation seeking to minimize the risks to healthy donors. We gradually decreased the lower limit of the GRWR to preferentially select a left-lobe over a right-lobe graft: from ≥0.7% beginning in December 2007 to ≥0.6% beginning in April 2009. A portal pressure control program, targeting final portal pressures below 15 mm Hg, was also introduced to overcome small-for-size graft problems. The ratio of left-lobe grafts among all adult-to-adult LDLT grafts and the donor complication rate (defined as Clavien grade ≥ III, excluding wound infection) were compared between two time periods: June 1999 to November 2007 (period 1, n = 541) and December 2007 to February 2010 (period 2, n = 119). Overall survival rates were also compared between those recipients of a GRWR < 0.8% and those with a GRWR ≥ 0.8% in 198 recipients who underwent LDLT at our institution between April 2006 and February 2010. RESULTS Left-lobe grafts use increased from period 1 (65/541 recipients; 12.0%) to period 2 (50/119 recipients; 42.0%; P < .001). The donor complication rate tended to decrease from 13.8% in period 1 to 9.3% in period 2 (P = .115). The overall survival rate in 52 recipients with a GRWR < 0.8% did not differ from that in 146 recipients with a GRWR ≥ 0.8%. CONCLUSIONS The lower limit of the GRWR can be safely reduced to 0.6% in adult-to-adult LDLT in combination with portal pressure control.
Journal of Clinical Microbiology | 2003
Tatsuji Kimura; Akinori Rokuhara; Akihiro Matsumoto; Shintaro Yagi; Eiji Tanaka; Kendo Kiyosawa; Noboru Maki
ABSTRACT A new enzyme immunoassay specific for hepatitis B virus (HBV) core antigen (HBcAg) was developed. In order to detect HBcAg, specimens were pretreated with detergents to release HBcAg from the HBV virion and disassemble it to dimers, and simultaneously, the treatment inactivated anti-HBc antibodies. HBcAg detected by the assay peaked with HBV DNA in density gradient fractions of HBV-positive sera. The assay showed a wide detection range from 2 to 100,000 pg/ml. We observed no interference from anti-HBc antibody or blood components, but the assay was inhibited by very high concentrations (>1 μg/ml; corresponding to 80 signal/cutoff) of HBeAg. When the cutoff value was tentatively set at 4 pg/ml, all healthy control (HBsAg and HBV DNA negative, n = 160) and anti-hepatitis C virus-positive (n = 55) sera were identified as negative. HBcAg concentrations correlated very closely with HBV DNA (r = 0.946, n = 145) in 216 samples from 72 hepatitis B patients. In seroconversion panels, HBcAg concentrations changed in parallel with HBV DNA levels. The assay, therefore, offers a simple method for monitoring hepatitis B patients. With a series of sera during lamivudine therapy, HBV DNA levels fell sharply and the HBcAg concentration also decreased, but the change in HBcAg was smaller and more gradual. The supposed mechanism of these changes and their clinical significance are discussed.
Journal of Medical Virology | 2000
Akinori Rokuhara; Eiji Tanaka; Shintaro Yagi; Masashi Mizokami; Yasuhiko Hashikura; Seiji Kawasaki; Kendo Kiyosawa
De novo infection of hepatitis B virus (HBV) occurs after liver transplantation from donors with HBV markers that suggest past infection. In the present study, the complete nucleotide sequences of HBV derived from a donor and recipients were determined to determine the clinical and virological characteristics. A total of 57 donor‐recipient pairs, which underwent living‐related orthotopic liver transplantation, were enrolled in the present study; all were negative for HBsAg before transplantation. HBV DNA was tested in serum, liver tissue, and peripheral blood mononuclear cells (PBMCs) by the polymerase chain reaction (PCR). The nucleotide sequence of HBV was determined based on PCR products and the phylogenetic analysis. De novo infection of HBV was found in 3 of the 57 recipients. Anti‐HBc was positive in all donors of 3 recipients with the de novo infection but was positive only in 4 donors of the remaining 54 recipients (P=0.001). HBV DNA was detected in the liver but not in the serum or PBMCs in donor 3 whose recipient developed de novo HBV infection. The nucleotide sequence covering entire genome of HBV (3,215 bases) derived from the liver of donor 3 had a homology of 99.8–100% with that derived from the serum of corresponding recipient 3. The strain of recipient 3 showed the closest association with that of the donor 3 by phylogenetic analysis. Complete sequences from two recipients with de novo HBV infection including recipient 3 conserved the basic organisation of HBV genome. Analysis of the entire nucleotide sequence of HBV genome proved that HBV existed in the liver of the donor with anti‐HBc, and it caused de novo infection in the corresponding recipient. J. Med. Virol. 62:471–478, 2000.
Nutrition | 2012
Toshimi Kaido; Akira Mori; Yasuhiro Ogura; K. Ogawa; Koichiro Hata; Atsushi Yoshizawa; Shintaro Yagi; Shinji Uemoto
OBJECTIVE Infectious complications, including sepsis, that often occur after liver transplantation (LT) comprise the most frequent causes of in-hospital death. This study investigated the predictors of post-transplantation infectious complications to establish a strategy with which to improve short-term outcomes after LT. METHODS We used univariate and multivariate analyses to assess pre- and perioperative risk factors for post-transplantation infectious complications in 100 consecutive patients who underwent living donor LT from February 2008 through February 2010 at our institute. RESULTS Multivariate analysis showed that low preoperative body cell mass and the absence of preoperative supplementation with branched-chain amino acids were of prognostic significance for post-transplantation sepsis. In addition, Child-Pugh classification C and massive operative blood loss were independent risk factors for post-transplantation bacteremia, and preoperative low body cell mass was an independent risk factor for in-hospital death from infection. CONCLUSION Pretransplantation nutritional intervention and decreases in operative blood loss would help prevent post-transplantation infectious complications from developing during living donor LT. Branched-chain amino acid supplementation before LT affects the occurrence of infectious complications.
World Journal of Gastroenterology | 2015
Takehito Yamamoto; Shintaro Yagi; Hiromitsu Kinoshita; Yusuke Sakamoto; Kazuyuki Okada; Kenji Uryuhara; Takeshi Morimoto; Satoshi Kaihara; Ryo Hosotani
AIM To retrospectively analyze factors affecting the long-term survival of patients with pancreatic cancer who underwent pancreatic resection. METHODS From January 2000 to December 2011, 195 patients underwent pancreatic resection in our hospital. The prognostic factors after pancreatic resection were analyzed in all 195 patients. After excluding the censored cases within an observational period, the clinicopathological characteristics of 20 patients who survived ≥ 5 (n = 20) and < 5 (n = 76) years were compared. For this comparison, we analyzed the patients who underwent surgery before June 2008 and were observed for more than 5 years. For statistical analyses, the log-rank test was used to compare the cumulative survival rates, and the χ (2) and Mann-Whitney tests were used to compare the two groups. The Cox-Hazard model was used for a multivariate analysis, and P values less than 0.05 were considered significant. A multivariate analysis was conducted on the factors that were significant in the univariate analysis. RESULTS The median survival for all patients was 27.1 months, and the 5-year actuarial survival rate was 34.5%. The median observational period was 595 d. With the univariate analysis, the UICC stage was significantly associated with survival time, and the CA19-9 ≤ 200 U/mL, DUPAN-2 ≤ 180 U/mL, tumor size ≤ 20 mm, R0 resection, absence of lymph node metastasis, absence of extrapancreatic neural invasion, and absence of portal invasion were favorable prognostic factors. The multivariate analysis showed that tumor size ≤ 20 mm (HR = 0.40; 95%CI: 0.17-0.83, P = 0.012) and negative surgical margins (R0 resection) (HR = 0.48; 95%CI: 0.30-0.77, P = 0.003) were independent favorable prognostic factors. Among the 96 patients, 20 patients survived for 5 years or more, and 76 patients died within 5 years after operation. Comparison of the 20 5-year survivors with the 76 non-survivors showed that lower concentrations of DUPAN-2 (79.5 vs 312.5 U/mL, P = 0.032), tumor size ≤ 20 mm (35% vs 8%, P = 0.008), R0 resection (95% vs 61%, P = 0.004), and absence of lymph node metastases (60% vs 18%, P = 0.036) were significantly associated with the 5-year survival. CONCLUSION Negative surgical margins and a tumor size ≤ 20 mm were independent favorable prognostic factors. Histologically curative resection and early tumor detection are important factors in achieving long-term survival.