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Shinji Uemoto

Publications and source records attributed to Shinji Uemoto.

At least 19 recordsLinked to original sources
PubMed2006

In vivo luminescent imaging of cyclosporin A-mediated cancer progression in rats.

BACKGROUND: Immunosuppressed individuals undergoing organ transplantation are at increased risk of recurrences of initial cancers, although how immunosuppressive therapy increases early cancer metastasis remains unclear. METHODS: The metastatic fate of luciferase-expressing rat metastatic colon cancer cells (luc-RCN-H4) injected intravenously into the liver of syngeneic and allogeneic rats was examined in the presence of the immunosuppressant cyclosporin A (CsA) by in vivo luminescent technique. With respect to potential tumor-progressing factors, contribution of chemokine receptors and transforming growth factor (TGF)-beta1 to early metastasis was evaluated using their specific signaling inhibitors. RESULTS: F344 rats injected in the liver with luc-RCN-H4 cells did not always exhibit the formation of tumors and showed a dormant state as long as 60 days after inoculation without CsA. However, CsA released early luc-RCN-H4 cells from dormancy within 2 weeks at nearly 100% in liver and preferentially promoted metastasis to the lymph nodes (approximately 40%). A similar dissemination occurred even in minor histocompatibility complex-disparate hosts. As a tumor-progressing factor, RCN-H4 cells aberrantly expressed chemokine receptors CXCR4 and CCR7. The chemokine receptor (CXC) R4-specific antagonist AMD3100 decreased early metastasis of luc-RCN-H4 cells in rats with ischemic liver conditions (P<0.05), but CsA treatment did not enhance early adhesion. Use of CsA was able to facilitate TGF-beta1 expression and the subsequent TGF-beta-mediated random migration was blocked by the use of the specific signaling inhibitor SB431542 in vitro. CONCLUSIONS: Whereas the chemokine receptor expression by cancer cells is implicated with early organotropic dissemination even under CsA-mediated immune suppression, rather, CsA enhances the late-phase progression after tumor adhesion through TGF-beta1 expression.

Adenocarcinoma↗
PubMed2006

Impact of lymph node micrometastasis in hilar bile duct carcinoma patients.

AIM: To immunohistochemically examine micrometastasis and VEGF-C expression in hilar bile duct carcinoma (HBDC) and to evaluate the clinical significance of the results. METHODS: A total of 361 regional lymph nodes from 25 patients with node-negative HBDC were immunostained with an antibody against cytokeratins 8 and 18 (CAM 5.2), and immunohistochemical staining of VEGF-C was performed in 34 primary resected tumors. RESULTS: Lymph node micrometastasis was detected in 6 (24%) of the 25 patients and 10 (2.8%) of the 361 lymph nodes. Patients with micrometastasis showed significantly poorer survival rates than those without (P = 0.025). VEGF-C expression was positive in 17 (50%) of 34 HBDC, and significantly correlated with lymph node metastasis (P = 0.042) and microscopic venous invasion (P = 0.035). CONCLUSIONS: It is suggested that immunohistochemically detected lymph node micrometastasis has an impact on the outcome of HBDC. VEGF-C expression is highly correlated with lymph node metastasis in HBDC and might therefore be a useful predictor.

Adult↗
PubMed2006

Primary liposarcoma of gallbladder diagnosed by preoperative imagings: a case report and review of literature.

A 49-year-old Japanese woman was referred to our department because of high fever and a huge abdominal mass. Computed tomography (CT) and magnetic resonance (MR) imagings revealed a tumor, about 30 cm in diameter,occupied the right hepatic lobe and the peritoneal cavity. Abdominal angiography showed that the tumor was fed mainly by the cystic artery. We preoperatively diagnosed angiosarcoma of the gallbladder and performed tumor resection with cholecystectomy because the tumor was almost capsulated,however the posterior wall of the gallbladder attached to the tumor firmly. Histologically,the tumor was composed of spindle cells including lipoblasts with cellular pleomorphism, which were also detected in the muscular layer of the gallbladder. We finally diagnosed pleomorphic liposarcoma of the gallbladder. At 10 mo and 29 mo after the first operation, she underwent two more operations because of recurrence. Now she has a good quality of life 3 yr and 6 mo after the first operation.

Angiography↗
PubMed2006

Optimal portal venous circulation for liver graft function after living-donor liver transplantation.

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.

Adult↗
PubMed2006

K(ICG) value, a reliable real-time estimator of graft function, accurately predicts outcomes in adult living-donor liver transplantation.

Reliable monitoring enabling evaluation of graft function is crucial after living-donor liver transplantation (LDLT). A method to identify poor graft function at an early postoperative period would allow opportune intensive clinical management to bring about further improvements in LDLT outcomes. This study assessed the reliability of the indocyanine green (ICG) elimination rate constant (K(ICG)) value as an estimator of graft function and determined the actual temporal changes of K(ICG) after LDLT. K(ICG) values were measured using a noninvasive method in 30 adult recipients up to 28 days after LDLT. The receptor index (LHL15) based on liver scintigraphy, and graft parenchymal damage score based on histopathological findings were evaluated after LDLT and correlated well with simultaneous K(ICG). Thus, K(ICG) measured by noninvasive method was confirmed as accurately evaluating graft function. Changes of K(ICG) after LDLT in recipients with good graft function were maintained, after some falls in the early periods, and had a significant difference compared with those for recipients without good graft function; moreover, there were already significant differences in K(ICG) 24 hours after LDLT. Mean transit time reflecting systemic hemodynamics revealed that recipients without good outcomes fell into an unstable systemic hemodynamic state, and effective hepatic blood flow has a large influence on liver regeneration after LDLT. In conclusion, we suggested that K(ICG) values can predict clinical outcomes at the early postoperative period after LDLT by sharply reflecting the influence of systemic dynamics on splanchnic circulation.

Adult↗
PubMed2006

The role of living-donor liver transplantation in surgical treatment for hepatocellular carcinoma.

BACKGROUND/PURPOSE: The role of living-donor liver transplantation (LDLT) in the surgical treatment of patients with hepatocellular carcinoma (HCC) has not been established as yet. METHODS: Preliminary experience gained from 24 patients who underwent LDLT for HCC between March 2002 and November 2004, and the results of the 131 patients who underwent hepatic resection (HR) for HCC between January 1990 and December 2003 were retrospectively analyzed. The exclusion criteria for LDLT for HCC included extrahepatic metastasis and major vascular invasion. RESULTS: (1) LDLT: the median age of the patients was 57 years and the Child-Pugh grades (A/B/C) of the patients were 6, 12, and 6, respectively. The tumor size was 3 cm or less in 15 patients, multinodular tumors were present in 23 patients, and 11 patients (45.8%) met the Milan Criteria. The overall 2-year survival rate was 72.3%, without a significant difference as to whether or not patients met the Milan criteria. (2) HR: on multivariate analysis, the Child-Pugh grade, the presence of cirrhosis, and the number of tumor nodules were considered as independent risk factors for unfavorable survival (P < 0.05). The 84 patients who met the Milan criteria and were Child-Pugh grade A had a 5-year survival rate of 71.3%; this was significantly better than those of the other patients (P < 0.005). Among the 57 patients with intrahepatic recurrence, 18 patients who were Child-Pugh grade A, met the Milan criteria, and were treated by re-resection or ablation therapy achieved a significantly better 5-year survival rate, of 73.1%, as compared to 19.7% in the other 39 patients (P < 0.0045). CONCLUSIONS: HR could be a first-line treatment with a favorable prognosis for patients who have resectable HCC, preserved liver function, and who meet the Milan criteria. Salvage LDLT could be employed in patients with recurrent tumors that cannot be controlled by conventional treatment or in patients in whom liver function has deteriorated to Child-Pugh grade B or C.

Adult↗
PubMed2005

Drug delivery system using microspheres that contain tacrolimus in porcine small bowel transplantation.

Rejection remains a major barrier to successful bowel transplantation, in spite of improved immunosuppressive techniques. Therefore, new, more effective, immunosuppressants, with fewer side effects, are needed. Biodegradable microspheres containing tacrolimus (FK506) were used in an experimental porcine small bowel transplantation. Twenty pigs underwent transplantation and were divided into four groups according to the immunosuppressive regimen. Group A (n = 5): no immunosuppression; group B (n = 6): 0.2 mg/kg per day of FK506; group C (n = 3): 1.0 mg/kg per day of FK506; group D (n = 6): 0.04 mg/kg per day of FK506 contained in biodegradable microspheres. Rejection was diagnosed macroscopically by endoscopic examination and histologically by biopsy specimen analysis. The mean survival time and standard deviation (SD) were 8.8+/-3.5, 11.0+/-1.4, 9.7+/-2.5 and 28.6+/-22.5 days for groups A, B, C, and D, respectively, with a statistically significant difference found between group D, on the one hand, and groups A, B and C, on the other. The mean trough blood concentration of FK506 was 10.5+/-2.2, 27.9+/-6.0 and 10.5+/-3.5 ng/ml in groups B, C and D, respectively. In groups A and B, all pigs died of rejection, without infection. In group C, all died of infection, without rejection. In contrast, none of the pigs in group D developed rejection or infection. Our results clearly show that the drug delivery system using biodegradable microspheres that contain FK506 is effective for controlling rejection with fewer side effects in the porcine small bowel transplantation.

Animals↗
PubMed2005

Hepatitis B virus infection in lymphatic tissues in inactive hepatitis B carriers.

BACKGROUND/AIMS: Hepatitis B virus (HBV) infection in extrahepatic tissues is controversial. To clarify whether episomal HBV can infect nonhepatic tissues, we investigated the molecular forms of HBV in the lymphatic cells of inactive HBV carriers who lacked viremia, thus avoiding contamination with HBV genomes originating from the viral particles present in the serum. METHODS: We assessed HBV genome, replicative forms, and viral integrants in the liver, serum, peripheral blood mononuclear cells (PBMC), and lymph nodes of 21 inactive HBV carriers who tested positive for antibodies against the HBV core antigen (anti-HBc). RESULTS: Of the 21 anti-HBc positive individuals, HBV-DNA was detected in liver samples of 15 (71.4%), in the lymph nodes of 11 (52.4%), and in PBMC of three (14.3%). However, none of the detected HBV genomes from lymphatic tissues included the replicative forms of HBV. In one case, integrated HBV was present in the lymphatic tissues and the host-viral junction was present in the intronic sequences of chromosome 17. CONCLUSIONS: These data suggest that human lymphatic tissues cannot support viral replication in anti-HBc positive inactive HBV carriers, while retaining the viral genome as an integrated form.

Adult↗
PubMed2005

Noninvasive ventilation for pediatric patients including those under 1-year-old undergoing liver transplantation.

Pulmonary complications are an important cause of the mortality associated with liver transplantation. The efficacy of noninvasive ventilation (NIV) in pediatric patients following transplantation is unknown. The purpose of this retrospective study is to investigate the effects of NIV for pediatric patients undergoing liver transplantation. Of 102 pediatric patients who underwent liver transplantation, 15 patients (aged 73 months; range 2.5-179) were supported by NIV because of atelectasis, hypercapnia, hypoxemia, pneumonia, massive effusion, or postextubation ventilatory support. Of 15 patients, 5 were under the age of 1 year (range 2.5-12 months). Of the 15 patients, 7 had required multiple intubations before NIV treatment because of pulmonary complications. NIV treatment was administered to 6 patients because of hypercapnia. Partial pressure of arterial carbon dioxide (PaCO(2)) levels improved from 56.9 (95% confidence interval [CI]: 48.4-65.4) to 41.5 (95% CI: 36.8-46.2) mmHg (P = .028) within 2 days. NIV treatment was very effective for patients with atelectasis with and without other pulmonary complications. Mean inspiratory positive pressure (IPAP) was 7.2 (95% CI: 6.0-8.3) cm H(2)O and expiratory positive pressure (EPAP) was 3.5 (95% CI: 3.2-3.9) cm of H(2)O. Mean duration of NIV was 18.5 (95% CI: 8.6-28.4) days. IPAP and EPAP levels were closely and significantly correlated with height (IPAP: r = .65, P = .016; EPAP: r = .77, P = .004). A total of 13 patients recovered and 2 patients died. However, no patient died of respiratory complications. In conclusion, NIV is effective in pediatric patients undergoing liver transplantation with subsequent pulmonary complications. The IPAP and EPAP levels may be predicted by the height of the patient.

Adolescent↗
PubMed2005

Impact of portal venous pressure on regeneration and graft damage after living-donor liver transplantation.

Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels.

Adult↗
PubMed2005

Role of bcl-2 mRNA in homeostatic proliferation in circulating T-cells in human liver transplant patients after T-cell depletion.

BACKGROUND: Prolonged T-cell depletion after liver transplantation leads to life-threatening infections. Members of the anti-apoptotic Bcl-2 gene family can maintain T-cell viability. T-cell numbers and their Bcl-2 expression following living donor liver transplantation (LDLT) were analyzed in 108 surviving and 13 deceased recipients. MATERIALS AND METHODS: Bcl-2 mRNA levels and phenotypic changes of T-cells were examined by quantitative PCR and by measuring expression of CD45RO and CCR7. RESULTS: Based on the restoration of peripheral T-cell numbers, the 108 surviving recipients were classified into three groups. All recipients showed T-cell depletion, down to approximately 30% of pretransplant levels within 3 h of graft reperfusion. In Group I, the T-cell numbers were rapidly restored to pretransplant levels, within 5 days, with a rapid decrease in Bcl-2 mRNA levels immediately after LDLT. In Group II, the T-cell numbers were restored to normal levels by 19 days, with down-regulation of Bcl-2 mRNA. In Group III, the T-cell numbers were maintained at low levels for much longer, with high levels of Bcl-2 mRNA. In all three groups of recipients, there was statistically significant (r = -0.78) inverse correlation between T-cell numbers and Bcl-2 mRNA. CONCLUSIONS: For successful transplantation, homeostatic restoration of T-cells must occur as soon as possible. Evaluation of peripheral T-cell numbers and of Bcl-2 expression may have therapeutic potential in identifying those transplant patients who face increased risk of infection.

Adolescent↗
PubMed2005

Approach to fine-needle aspiration cytology-negative cases of breast cancer.

OBJECTIVE: To clarify the clinical usefulness of fine-needle aspiration (FNA) cytology of breast tumours and the management of FNA cytology-negative cases suspected of or equivocal for malignancy. METHODS: FNA cytology was performed in 94 patients between 1995 and 2002. We calculated the sensitivity, specificity and accuracy of FNA cytology for the diagnosis of malignancy. We also compared clinical and radiological findings between false-negative and true-negative cases. RESULTS: The sensitivity of FNA was 91% (72/79), specificity was 93% (14/15), accuracy was 91% (86/94), positive predictive value was 99% (72/73) and negative predictive value was 67% (14/21). There were seven false-negative cases and one false-positive case. Findings that aroused suspicion of malignancy were more frequent in the false-negative cases, especially from mammography and magnetic resonance imaging (MRI). CONCLUSION: FNA cytology was an accurate preoperative diagnostic procedure for the evaluation of breast masses. In FNA cytology-negative cases, repeated FNA, core needle biopsy or excisional biopsy needs to be performed based on MRI findings.

Algorithms↗
PubMed2005

Outflow block secondary to stenosis of the inferior vena cava following living-donor liver transplantation?

Although it is well known that outflow block is caused by stenosis or occlusion of hepatic vein anastomoses following living donor liver transplantation (LDLT), there have been few reports on inferior vena cava (IVC) stenosis following LDLT. In this paper, we report two cases of IVC stenosis and hepatic vein outflow block following right hepatic LDLT in the absence of stenosis of any of the anastomoses. Both patients presented with liver dysfunction, an ascitic fluid volume of approximately 2000 mL, and congestion in their biopsy specimens, and venocavography demonstrated IVC stenosis with gradients of more than 10 mmHg in patients with a dominant inferior right hepatic vein (IRHV) anastomosis. After a Gianturco expandable metallic stent successfully implanted in the IVC, the patient's liver function recovered and the volume of ascitic fluid decreased. The pathogenesis of hepatic vein outflow block secondary to IVC stenosis following LDLT may involve the anastomosis with the IRHV, which is the dominant draining vein of the graft and larger than the RHV, caudal to the IVC stenosis and a significant IVC pressure gradient that results in increased IRHV pressure. In conclusion, it is important to include hepatic vein outflow block in the differential diagnosis when patients who have undergone right hepatic LDLT in which anastomosis of the large IRHV has been performed develop manifestations of liver dysfunction.

Adult↗
PubMed2005

Using a radial artery as an interpositional vascular graft in a living-donor liver transplantation for hepatocellular carcinoma.

With increasing numbers of living-donor liver transplantations (LDLTs) for hepatocellular carcinoma (HCC), cases with some arterial troubles are encountered; because most HCC cases waiting for LDLT have undergone interventional treatments. In these patients, the reconstruction of the graft artery needs to be planned preoperatively. We report a 52-year-old male, with hepatitis C-related liver cirrhosis and advanced HCC, who for 4 years repeatedly underwent continuous intraarterial chemotherapy through an implanted reservoir port. A suitable artery was not available for arterial reconstruction and the patient underwent LDLT using an autologous radial artery conduit based on the infrarenal aorta. Postoperatively, the patient is well with normal liver function and efficient arterial flow. Autologous radial artery can be safely and successfully used as an aortic-based arterial conduit when HCC patients waiting for LDLT have undergone long-term repeated intraarterial chemotherapy.

Angiography↗
PubMed2005

Donor outcome and liver regeneration after right-lobe graft donation.

Sufficiently detailed information on donor safety and the liver regeneration process following right-lobe living donation has been unavailable, so we evaluated donor outcome and liver regeneration in 13 males and 14 females (39.0 +/- 14.8 years old) who provided 27 right-lobe grafts without the middle hepatic vein. Preoperative total liver volume (TLV), graft volume, and postoperative changes in residual liver volume (RLV) were measured by volumetric computed tomography. Histological steatosis of the liver was graded as none, minimal (< or =10%), and mild (11-30%). The median follow-up period was 337 days. Estimated graft volume and actual graft weight were linearly correlated (Y = 177.85 + 0.795X, R(2) = 0.812, P < 0.0001). Graft-to-recipient weight ratio was 1.08 +/- 0.19%. Four donors had postoperative complications, but they resolved in response to conservative treatment. Postoperative hospital stay was 15.2 +/- 5.5 days. Peak liver enzyme values were significantly higher in donors with mild steatosis (n = 7) than without steatosis (n = 16) (P < 0.05). Donor RLV was 40.8 +/- 6.6% of original TLV at surgery, 79.8 +/- 12.0% by 6 months, and 97.2 +/- 10.8% by 12 months. At 3 months the liver of the older donors (> or =50 years) had grown significantly more slowly than in younger donors (70.4 +/- 9.2% vs. 79.3 +/- 9.6%, P = 0.0391). In conclusion, right hepatectomy without middle hepatic vein of living donors is a safe procedure with acceptable morbidity, and the residual liver regenerated to its preoperative size by 1 year. However, meticulous care should be taken in donors with liver steatosis and aged donors.

Adult↗