Hepatic artery reconstruction with the jejunal artery of the Roux-en-Y limb in pediatric living donor liver re-transplantation.

When re-anastomosis and re-transplantation becomes necessary after LDLT, arterial reconstruction can be extremely difficult because of severe inflammation and lack of an adequate artery for reconstruction. Frequently, the recipient's HA is not in good condition, necessitating an alternative to the HA. In such cases, the recipient's splenic artery, right gastroepiploic artery or another vessel can be safely used for arterial reconstruction. There have, however, been few reports on using the jejunal artery. Herein, we report our experience with arterial reconstruction using the jejunal artery of the Roux-en-Y limb as an alternative to the HA. A three-yr-old girl who had developed graft failure due to early HA thrombosis after LDLT required re-transplantation. At re-transplantation, an adequate artery for reconstruction was lacking. We reconstructed the artery by using the jejunal artery of the Roux-en-Y limb, as we judged it to be the most appropriate alternative. After surgery, stent was deployed because hepatic blood flow had reduced due to kinking of the anastomosed site, and a favorable outcome was obtained. In conclusion, when an alternative to the HA is required, using the jejunal artery is a feasible alternative.

Interventional radiology for hepatic artery complications soon after living donor liver transplantation in a neonate.

Early hepatic artery complications after liver transplantation in children, having undergone LDLT, can directly affect graft and recipient outcomes, making early diagnosis and treatment essential. In the past, laparotomy (thrombectomy or reanastomosis) was generally employed to treat early hepatic artery complications. Recently, favorable outcomes of IR have been reported. In children, however, the number of such reports is small. To the best of our knowledge, there is no published report on IR applied to neonates with early hepatic artery complications. We recently succeeded in safely using IR for a neonate with early hepatic artery complications after LDLT and obtained a favorable outcome. This case is presented herein.

Living donor liver transplantation from an asymptomatic mother who was a carrier for ornithine transcarbamylase deficiency.

Liver transplantation (LT) has been adopted as a radical treatment for ornithine transcarbamylase deficiency (OTCD), yielding favorable outcomes. Despite the fact that it is an inheritable disease, a blood relative who is heterozygous for the disorder must sometimes be used as a liver donor for living donor LT. There is ongoing discussion regarding the use of heterozygous donors, however, to our knowledge, no cases where donation was determined based on the Ornithine transcarbamylase (OTC) activity before LT have been reported. Between May 2001 and April 2011, 17 patients were indicated for living donor LT because of OTCD at our facility. There were three cases with heterozygous donor candidate (17.6%). All heterozygous candidates underwent a liver biopsy to measure their OTC activity before LT and made efforts to secure the safety of the both donor and recipient. Two of 3 candidates had headaches sometimes, and their activity was less than 40%, and thus they were not employed as the donor. One candidate with 104.4% activity was employed, yielding favorable outcomes. Our current experience supported the effectiveness of our donation criteria, however it is necessary to collect sufficient data on a large number of patients to confirm the safety of the procedure.

Pediatric liver retransplantation from living donors can be considered as a therapeutic option for patients with irreversible living donor graft failure.

Liver retransplantation (re-LT) is required in patients with irreversible graft failure, but it is a significant issue that remains medically, ethically, and economically controversial, especially in living donor liver transplantation (LDLT). The aim of this study was to evaluate the outcome, morbidity, mortality, safety and prognostic factors to improve the outcome of pediatric living donor liver retransplantation (re-LDLT). Six of 172 children that underwent LDLT between January 2001 and March 2010 received a re-LDLT and one received a second re-LDLT. The overall re-LDLT rate was 3.5%. All candidates had re-LDLT after the initial LDLT. The overall actuarial survival of these patients was 83.3% and 83.3% at one and five yr, respectively. These rates are significantly worse than the rates of pediatric first LDLT. Vascular complications occurred in four patients and were successfully treated by interventional radiologic therapy. There were no post-operative biliary complications. One case expired because of hemophagocytic syndrome after re-LDLT. Although pediatric re-LDLT is medically, ethically, and economically controversial, it is a feasible option and should be offered to children with irreversible graft failure. Further investigations, including multicenter studies, are therefore essential to identify any prognostic factors that may improve the present poor outcome after re-LDLT.

Living donor liver transplantation for ornithine transcarbamylase deficiency.

Ornithine transcarbamylase deficiency, the most common urea cycle disorder, causes hyperammonemic encephalopathy and has a poor prognosis. Recently, LT was introduced as a radical OTCD treatment, yielding favorable outcomes. We retrospectively analyzed LT results for OTCD at our facility. Twelve children with OTCD (six boys and six girls) accounted for 7.1% of the 170 children who underwent LDLT at our department between May 2001 and April 2010. Ages at LT ranged from nine months to 11 yr seven months. Post-operative follow-up period was 3-97 months. The post-operative survival rate was 91.7%. One patient died. Two patients who had neurological impairment preoperatively showed no alleviation after LT. All patients other than those who died or failed to show recovery from impairment achieved satisfactory quality-of-life improvement after LT. The outcomes of LDLT as a radical OTCD treatment have been satisfactory. However, neurological impairment associated with hyperammonemia is unlikely to subside even after LT. It is desirable henceforth that more objective and concrete guidelines for OTCD management be established to facilitate LDLT with optimal timing while avoiding the risk of hyperammonemic episodes.

Living donor liver transplantation for neonates using segment 2 monosubsegment graft.

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.

"Bonnet" bypass to proximal trunk of middle cerebral artery with a radial artery interposition graft: technical note.

BACKGROUND: Anastomosis of the superficial temporal artery (STA) to the middle cerebral artery (MCA) is useful for treating certain patients with internal carotid artery occlusion or MCA occlusion. However, in the case of common carotid artery (CCA) occlusion, since the blood flow in the STA is insufficient, another artery should be used as the donor artery. The cortical branches of the MCA are usually selected as recipients in the STA-MCA bypass. However, the intracranial vascular filling gradually increases over a few months after conventional cortical MCA bypass grafting, while early or even immediate vascular filling is observed after proximal MCA bypass grafting. This study aims to develop an elongation technique of the contralateral STA to reach the proximal segment of the ipsilateral MCA. METHODS: Anastomosis of the contralateral STA to the secondary trunk of the ipsilateral MCA was performed in 2 patients with occlusion of the CCA and ipsilateral vertebral artery (VA). The contralateral STA was extended with a radial artery (RA) graft in order to supply blood to the ischemic area. Elongation of the STA by using an RA interposition graft sufficiently lengthens the graft to enable its anastomosis with the contralateral M2 segment. Postoperative imaging revealed good bypass patency even at 1 year after the surgery. CONCLUSION: This novel technique of performing the "bonnet" bypass was effective in treating both CCA and ipsilateral VA occlusion; moreover, this procedure of elongation of the STA can increase candidates of the recipient, and enables one to perform a double bypass to the anterior cerebral artery (ACA) or posterior cerebral artery (PCA).

APPLICATION OF THE FOREST SHIELDING FACTOR TO THE MAXIMUM-LIKELIHOOD EXPECTATION MAXIMIZATION METHOD FOR AIRBORNE RADIATION MONITORING.

The maximum-likelihood expectation maximization (ML-EM) method is expected to improve the accuracy of airborne radiation monitoring using an unmanned aerial vehicle. The accuracy of the ML-EM method depends on various parameters, including detector efficiency, attenuation factor, and shielding factor. In this study, we evaluate the shielding factor of trees based on several field radiation measurements. From the actual measurement, the shielding factors were well correlated with the heights of the trees. The evaluated shielding factors were applied to the ML-EM method in conjunction with the measured data obtained from above the Fukushima forest. Compared with the conventional methods used for calculating the dose rate, the proposed method is found to be more reliable.

Endotoxin Metabolism Reflects Hepatic Functional Reserve in End-Stage Liver Disease.

BACKGROUND: The hepatic clearance of endotoxin (Et) may reflect hepatic functional reserve and ischemic injury to hepatocytes. Therefore, we examined the relationships between Et activity (EA) and the metrics Pediatric End-Stage Liver Disease (PELD)/Model of End-Stage Liver Disease (MELD) score and alanine transaminase (ALT) levels in the postoperative period. METHODS: We performed 8 living-donor liver transplantations (LDLTs) for biliary atresia at our center from April 2012 to December 2012. EA was measured by means of an Et activity assay (EAA) in samples collected from a vein 1 day before LDLT, from the portal vein during the intraoperative anhepatic phase, from an artery 1 hour after reperfusion, from an artery on postoperative day (POD) 1, and from an artery or vein at PODs 7 and 14. RESULTS: EAs generally remained at low levels. EA at the reperfusion period was significantly lowest. The correlation coefficient for the preoperative MELD/PELD score and the EAA was 0.837, and the corresponding P value was .009; thus, there was a significant relationship between the preoperative MELD/PELD score and the EAA. The correlation coefficients for ALT at POD 1 and EA during the anhepatic phase, at 1 hour after reperfusion, and at POD 1 were 0.64, 0.43, and 0.38, respectively, and the P values for these correlations were .08, .67, and .34. Thus, we observed that ALT and EA generally tended to be somewhat directly correlated, but no significant relationships between these 2 metrics were observed. CONCLUSIONS: Endotoxin metabolism reflects the hepatic functional reserve capacity of end-stage liver disease.

Transition of Spleen Volume Long After Pediatric Living Donor Liver Transplantation for Biliary Atresia.

PURPOSE: After undergoing the Kasai procedure for biliary atresia (BA), most patients develop severe splenomegaly that tends to be improved by liver transplantation. However, fluctuations in splenic volume long after transplantation remain to be elucidated. PATIENTS AND METHODS: Seventy-one consecutive patients who had undergone pediatric living donor liver transplantation (LDLT) for BA were followed up in our outpatient clinic for 5 years. They were classified into 3 groups according to their clinical outcomes: a good course group (GC, n = 41) who were maintained on only 1 or without an immunosuppressant, a liver dysfunction group (LD, n = 18) who were maintained on 2 or 3 types of immunosuppressants, and a vascular complication group (VC, n = 11). Splenic and hepatic volumes were calculated by computed tomography in 464 examinations and the values compared before and after the treatment, especially in the VC group. RESULTS: Splenic volume decreased exponentially in the GC group, with splenic volume to standard spleen volume ratio (SD) being 1.59 (0.33) 5 years after liver transplantation. Splenic volume to standard spleen volume ratios were greater in the VC and LD groups than in the GC group. Patients in the VC group with portal vein stenosis developed liver atrophy and splenomegaly, whereas those with hepatic vein stenosis developed hepatomegaly and splenomegaly. Interventional radiation therapy tended to improve the associated symptoms. CONCLUSIONS: Fluctuations in splenic volume long after pediatric LDLT for BA may reflect various clinical conditions. Evaluation of both splenic and hepatic volumes can facilitate understanding clinical conditions following pediatric LDLT.

Antibody Drug Treatment for Steroid-Resistant Rejection After Pediatric Living Donor Liver Transplantation: A Single-Center Experience.

BACKGROUND: Antibody drugs have been used to treat steroid-resistant rejection (SRR) after liver transplantation. Although anti-thymocyte globulin has been used for SRR after liver transplantation in place of muromonab-CD3 since 2011 in Japan, the effectiveness of anti-thymocyte globulin after pediatric living-donor liver transplantation (LDLT) has not yet been reported. The aim of this study was to evaluate the effectiveness of antibody drug treatment for SRR after pediatric LDLT in our single center. METHODS: Between May 2001 and December 2013, 220 pediatric LDLTs were performed. Initial immunosuppression after LDLT included tacrolimus and methylprednisolone therapy. Acute rejection was diagnosed by use of a liver biopsy and the administration of steroid pulse treatment, and SRR was defined as acute rejection refractory to the steroid pulse treatment. RESULTS: Acute rejection and SRR occurred in 74 (33.6%) and 16 patients (7.3%), respectively. The graft survival rates of non-SRR and SRR were 92.4% and 87.5%, respectively (P = .464). The median concentration of alanine aminotransferase before and after the administration of antibody drug was 193.5 mU/mL (range, 8-508) and 78 mU/mL (range, 9-655), respectively (P = .012). The median rejection activity index before and after the administration of antibody drugs was 5 (range, 2-9) and 1 (range, 0-9), respectively (P = .004). After antibody drug treatment, 12 patients had cytomegalovirus infections, 2 patients had Epstein-Barr virus infections, 3 patients had respiratory infections, and 1 patient had encephalitis. The cause of death in 1 patient with SRR was recurrence of infant fulminant hepatic failure. CONCLUSIONS: Antibody drug treatment for SRR after pediatric LDLT is safe and effective.

Relationship Between Graft Liver Function and the Change of Graft Liver and Spleen Volumes After Technical Variant Liver Transplantation.

BACKGROUND: Although there have been a few reports describing the changes of graft liver and spleen volumes after liver transplantation (LT), little is known about the relationship between graft liver function and the changes of these volumes after technical variant liver transplantation (TVLT). We therefore performed a retrospective study to investigate the relationship between graft liver function and these volumes after TVLT. METHODS: We retrospectively investigated the cases of 140 TVLT procedures that were performed in our department between July 1987 and October 2012 and in which follow-up was conducted at our department. We calculated the graft liver volume to standard liver volume (GV/SLV) ratio, the spleen volume to standard spleen volume (SV/SSV) ratio, and the spleen volume to graft liver volume (S/L) ratio by CT volumetry. We clarified the relationship between graft liver function (according to the pathological findings) and the graft liver and spleen volumes at 2, 5, and 10 years after TVLT. RESULTS: In the normal liver function group, the GV/SLV, SV/SSV, and S/L ratios decreased until 6 months after TVLT and then converged at 10 years after TVLT to 0.95, 1.27, and 0.27, respectively. In the graft liver failure group, the GV/SLV, SV/SSV, and S/L ratios at 10 years after TVLT were 0.67, 5.01, and 1.55, respectively. A significant correlation was observed between the GV/SLV ratio and the presence of mild liver fibrosis at 2 and 5 years after TVLT (P = .03 and P = .04, respectively). CONCLUSIONS: Post-transplant CT-volumetry is a noninvasive and effective means of evaluating graft liver status.

Complementary Indicators for Diagnosis of Hepatic Vein Stenosis After Pediatric Living-donor Liver Transplantation.

INTRODUCTION: Although hepatic vein stenosis after liver transplantation is a rare complication, the complication rate of 1% to 6% is higher in pediatric living-donor liver transplantation than that in other liver transplantation cases. Diagnosis is very important because this complication can cause hepatic congestion that develops to liver cirrhosis, graft loss, and patient loss. However, this is unlikely in cases where there are no ascites or hypoalbuminemia. OBJECTIVES: Eleven of 167 patients who had undergone pediatric living-donor liver transplantation were identified in the outpatient clinic at Jichi Medical University as having suffered from hepatic vein stenosis, and were enrolled in the study. METHODS: We conducted a retrospective study in which we reviewed historical patient records to investigate the parameters for diagnosis and examine treatment methods and outcomes. RESULTS: The 11 patients were treated with 16 episodes of balloon dilatation. Three among these received retransplantation and another 2 cases required the placement of a metallic stent at the stenosis. Histological examination revealed severe fibrosis in four of nine patients who had a liver biopsy, with mild fibrosis revealed in the other five grafts. Furthermore, hepatomegaly and splenomegaly diagnosed by computed tomography, elevated levels of hyarulonic acid, and/or a decrease in calcineurin inhibitor clearance were found to be pathognomonic at diagnosis, and tended to improve after treatment. CONCLUSIONS: Diagnosis of hepatic vein stenosis after liver transplantation can be difficult, so careful observation is crucial to avoid the risk of acute liver dysfunction. Comprehensive assessment using volumetry of the liver and spleen and monitoring of hyarulonic acid levels and/or calcineurin inhibitor clearance, in addition to some form of imaging examination, is important for diagnosis and evaluation of the effectiveness of therapy.

Living-Donor Liver Transplantation Using Segment 2 Monosegment Graft: A Single-Center Experience.

BACKGROUND: In small infants, left lateral segment grafts are sometimes too large to overcome the problems of large-for-size grafts in the abdominal compartment. To address this problem, we have developed a safe living donor graftectomy for neonates, a so-called "S2 monosegment graft" to minimize graft thickness. We reviewed our single-center experience to evaluate the feasibility of this technique for reducing graft size. METHODS: Eleven living-donor liver transplants using S2 monosegment grafts were performed between October 2008 and September 2014 at our institution. Medical records of both donors and recipients were reviewed and data collected retrospectively. RESULTS: The mean age of recipients at the time of transplantation was 125.3 days, including 3 neonates. The average S2 monosegment graft weight was 127.4 g, and the graft-to-recipient body weight ratio was successfully reduced to 3.5%. The graft livers were reduced to 4.1 cm in thickness. Two recipients with grafts larger than 5 cm could not undergo primary abdominal closure. Portal vein stenosis and biliary stenosis was observed in 1 recipient, and hepatic artery complications were seen in 2 recipients; the clinical course for all donors were uneventful. Liver regeneration was seen in every patient. The graft and patient 1-year survival rate was 100%. CONCLUSIONS: Living-donor liver transplantation using S2 monosegment grafts offers a safe and useful option for treating smaller infants. Here, we introduce our method of S2 monosegment graft emphasizing the donor harvest and graft thickness.

Reactive oxygen species enhances the induction of inducible nitric oxide synthase by sphingomyelinase in RAW264.7 cells.

The sphingomyelin pathway, activated by stimuli, such as inflammatory cytokines, results in the formation of ceramide, a second messenger molecule. The purpose of the present study was to examine the mechanism by which macrophage-type nitric oxide synthase (NOS II) is induced by stimulation of the sphingomyelin pathway. When RAW264.7 cells were incubated with sphingomyelinase (SMase), nitrite production, NOS II activity, and NOS II mRNA were increased in a dose-dependent manner. Sphingosine, dihydrosphingosine, N-acetylsphingosine (C2-ceramide), and N-acylsphingosine (natural ceramide) had no effect on nitrite production, suggesting that signal molecules other than these were concomitantly produced by SMase treatment and required for NOS II induction. We then investigated the possible involvement of intracellular reactive oxygen species (ROS) in gene induction. SMase treatment increased the level of intracellular ROS, as assessed by flow cytometric analysis using a ROS-sensitive dye, dichlorofluorescin diacetate. Antioxidants, such as N-acetyl-l-cysteine and alpha-tocopherol, inhibited gene induction as well as nitrite production by SMase. These results suggest that activation of the sphingomyelin pathway induces gene expression and that the elevated ROS were somehow involved in this process.

A novel split liver protocol using the subnormothermic oxygenated circuit system in a porcine model of a marginal donor procedure.

BACKGROUND: A merit of subnormothermic perfusion has been reported to preserve grafts from ischemic injury in animal models. The split liver technique is commonly performed to solve the shortage of liver grafts. However, there has been no study showing the effect of a split liver graft on subnormothermic perfusion. We herein investigated the split liver protocol using a subnormothermic oxygenated circuit system (SOCS). METHODS: Auxiliary liver transplantation was performed in a porcine marginal donor model by using a SOCS. In the SOCS group, the portal vein and hepatic artery of the graft were cannulated, and the graft was perfused by SOCS. In the cold storage (CS) group, the graft was placed in cold preservation solution. In the preservation phase, the graft was split. RESULTS: There were no significant differences in the biochemical markers between the SOCS and CS groups. In terms of the histology, the sinusoidal spaces were widened in the CS group 12 hours after implantation. CONCLUSION: We have demonstrated a possibility to use SOCS with the split liver protocol by using a porcine model. This split liver protocol using SOCS will extend the split liver criteria and rescue more patients from hepatic failure, including pediatric patients.

DEEP BIOSPHERE. Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor.

Microbial life inhabits deeply buried marine sediments, but the extent of this vast ecosystem remains poorly constrained. Here we provide evidence for the existence of microbial communities in ~40° to 60°C sediment associated with lignite coal beds at ~1.5 to 2.5 km below the seafloor in the Pacific Ocean off Japan. Microbial methanogenesis was indicated by the isotopic compositions of methane and carbon dioxide, biomarkers, cultivation data, and gas compositions. Concentrations of indigenous microbial cells below 1.5 km ranged from <10 to ~10(4) cells cm(-3). Peak concentrations occurred in lignite layers, where communities differed markedly from shallower subseafloor communities and instead resembled organotrophic communities in forest soils. This suggests that terrigenous sediments retain indigenous community members tens of millions of years after burial in the seabed.

Susceptibilities of various myofibrillar proteins to muscle serine protease.

The ability of serine protease of skeletal muscle to degrade native myofibrillar proteins, such as myosin, actin, troponin, tropomyosin, alpha-actinin, and M-protein from rabbit skeletal muscle was studied. The amino acids or peptides liberated from these proteins by the protease were determined fluorometrically using o-phthalaldehyde. The order of their susceptibilities at a molar ratio of the serine protease to substrate of 1:100 was: myosin greater than tropnin greater than tropomyosin greater than actin. Alpha-Actinin and M-protein were not degraded. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the myosin heavy chain was degraded into two fragments, having molecular weights of 100,000 and 88,000, whereas the light chains were scarcely degraded. The serine protease degraded troponin-T rapidly and troponin-I slowly, but did not degrade troponin-C. Tropomyosin was degraded rapidly into two components with molecular weights of 21,500 and 19,000. Actin was degraded slowly, but no liberated fragment could be detected.

Effect of a serine protease on isolated myofibrils.

Morphological changes occurred in myofibrils prepared from the glycerinated psoas muscle of rabbit during incubation with a serine protease crystallized from rat skeletal muscle. Two notable phenomena were observed: (1) loss of the Z band in the early stage of incubation and (2) complete disappearance of the A band after swelling of the myofibrils. The results indicate that the serine protease has an action on myofibrils different from that of Ca2+-dependent neutral protease.

Studies on the structure of rat liver ornithine aminotransferase.

Two distinct types of apoenzyme from native ornithine aminotransferase [EC 2.6.1.13], named forms I and II, have been found to be composed of a single type of subunit by means of Sephadex G-100 column chromatography in the presence of sodium dodecylsulfate, DE 52 cellulose column chromatography in the presence of 8 M urea and urea-polyacrylamide gel disc electrophoresis. The amino-terminal residues of both apoenzymes were blocked, but several amino acids in sequence from the carboxylterminals were identical and the following sequence was found in both: Phe-Ser-Leu-IIe-Ala-(Val)-. In the native enzyme, 4 SH groups out of a total 20 SH groups/tetramer could be titrated without loss of enzyme activity, while in the apo-form I, 4 SH groups out of a total 20 SH groups/tetramer could be titrated with 80% loss of activity. In the apo-form II, in contrast, 6 SH groups out of a total 10 SH groups/dimer could be titrated and titration of the first 2 SH groups caused 100% loss of activity.