Efficient gene transduction in pigs and macaques with the engineered AAV vector AAV.GT5 for hemophilia B gene therapy

Gene therapy using adeno-associated virus (AAV)-based vectors has become a realistic therapeutic option for hemophilia. We examined the potential of a novel engineered liver-tropic AAV3B-based vector, AAV.GT5, for hemophilia B gene therapy. In vitro transduction with AAV.GT5 in human hepatocytes was more than 100 times higher than with AAV-Spark100, another bioengineered vector used in a clinical trial. However, liver transduction following intravenous injection of these vectors was similar in mice with a humanized liver and in macaques. This discrepancy was due to the low recovery and short half-life of AAV.GT5 in blood, depending on the positive charge of the heparin-binding site in the capsid. Bypassing systemic clearance with the intra-hepatic vascular administration of AAV.GT5, but not AAV-Spark100, enhanced liver transduction in pigs and macaques. AAV.GT5 did not develop neutralizing antibodies (NAbs) in two of four animals, while AAV-Spark100 induced serotype-specific NAbs in all macaques tested (4 of 4). The NAbs produced after AAV-Spark100 administration were relatively serotype specific, and challenge with AAV.GT5 through the hepatic artery successfully boosted liver transduction in one animal previously administered AAV-Spark100. In summary, AAV.GT5 showed different vector kinetics and NAb induction compared with AAV-Spark100, and intra-hepatic vascular administration may minimize the vector dose required and vector dissemination.

[Methods for Recovering Residual Anticancer Drugs in Medical Settings to Improve Working Environments]

We examined the methods for recovering residual anticancer drugs in medical settings to prevent health hazards caused by exposure to anticancer drugs. Presently, the lactose hydrate recovery rates(Lac, an alternative sample for an anticancer drug)were determined using 2 drug recovery methods that are based on a procedure manual(procedure manual method) and smart remote support(remote support method). Using the procedure manual method, 5 healthcare workers recovered Lac after receiving a detailed face-to-face methodological explanation. Using the remote support method, 3 healthcare workers recovered Lac regarded by an instructor waiting at a remote site without using a procedure manual. As a result, the Lac recovery rates were>80% for both methods; however, they showed the need for improvement. Eventually, the issues found presently will be resolved to improve the working environments of healthcare workers, caregivers, and medical service providers.

Intra-cisterna magna delivery of an AAV vector with the GLUT1 promoter in a pig recapitulates the physiological expression of SLC2A1

Glucose transporter 1 deficiency syndrome (GLUT1DS) is caused by haplo-insufficiency of SLC2A1, which encodes GLUT1, resulting in impaired hexose transport into the brain. Previously, we generated a tyrosine-mutant AAV9/3 vector in which SLC2A1 was expressed under the control of the endogenous GLUT1 promoter (AAV-GLUT1), and confirmed the improved motor function and cerebrospinal fluid glucose levels of Glut1-deficient mice after cerebroventricular injection of AAV-GLUT1. In preparation for clinical application, we examined the expression of transgenes after intra-cisterna magna injection of AAV-GFP (tyrosine-mutant AAV9/3-GFP with the CMV promoter) and AAV-GLUT1. We injected AAV-GFP or AAV-GLUT1 (1.63 × 10¹² vector genomes/kg) into the cisterna magna of pigs to compare differential promoter activity. After AAV-GFP injection, exogenous GFP was expressed in broad areas of the brain and peripheral organs. After AAV-GLUT1 injection, exogenous GLUT1 was expressed predominantly in the brain. At the cellular level, exogenous GLUT1 was mainly expressed in the endothelium, followed by glia and neurons, which was contrasted with the neuronal-predominant expression of GFP by the CMV promotor. We consider intra-cisterna magna injection of AAV-GLUT1 to be a feasible approach for gene therapy of GLUT1DS.

Intestinal mucosa staple line integrity and anastomotic leak pressure after healing in a porcine model

PURPOSE

The aim of this study was to evaluate both the intestinal mucosa staple line integrity and anastomotic leak pressure after healing in a porcine survival model.

METHODS

We used two suture models using two different size staples (incomplete mucosal closure model: group G [staple height 0.75 mm], complete mucosal closure model: group B [staple height 1.5 mm]) in the porcine ileum. Five staple lines were created in each group made in the ileum for each model, and the staple sites harvested on days 0, 2, and 7. The leak pressure at the staple site was measured at each time point.

RESULTS

On day 0, the leak pressure for group G (79.5 mmHg) was significantly lower than that for group B (182.3 mmHg) (p < 0.01). On days 2 and 7, there was no significant difference between groups G and B (171 mmHg and 175.5 mmHg on day 2, 175.5 mmHg and 175.5 mmHg on day 7, p > 0.05). The histological findings in both groups showed similar healing at postoperative days 2 and 7.

CONCLUSION

The integrity of the mucosal staple lines was associated with the postoperative leak pressure on day 0. However, there was no association with the leak pressure at two days or more postoperatively in a porcine model.

Intramyocardial Transplantation of Human iPS Cell-Derived Cardiac Spheroids Improves Cardiac Function in Heart Failure Animals

The severe shortage of donor hearts hampered the cardiac transplantation to patients with advanced heart failure. Therefore, cardiac regenerative therapies are eagerly awaited as a substitution. Human induced pluripotent stem cells (hiPSCs) are realistic cell source for regenerative cardiomyocytes. The hiPSC-derived cardiomyocytes are highly expected to help the recovery of heart. Avoidance of teratoma formation and large-scale culture of cardiomyocytes are definitely necessary for clinical setting. The combination of pure cardiac spheroids and gelatin hydrogel succeeded to recover reduced ejection fraction. The feasible transplantation strategy including transplantation device for regenerative cardiomyocytes are established in this study.

Organ ischemia during partial resuscitative endovascular balloon occlusion of the aorta: Dynamic 4D Computed tomography in swine

Resuscitative endovascular balloon occlusion of the aorta (REBOA) increases proximal pressure, and simultaneously induces distal ischemia. We aimed to evaluate organ ischemia during partial REBOA (P-REBOA) with computed tomography (CT) perfusion in a swine model. The maximum balloon volume was recorded as total REBOA when the distal pulse pressure ceased. The animals (n = 4) were scanned at each 20% of the maximum balloon volume, and time-density curve (TDC) were analysed at the aorta, portal vein (PV), liver parenchyma, and superior mesenteric vein (SMV, indicating mesenteric perfusion). The area under the TDC (AUTDC), the time to peak (TTP), and four-dimensional volume-rendering images (4D-VR) were evaluated. The TDC of the both upper and lower aorta showed an increased peak and delayed TTP. The TDC of the PV, liver, and SMV showed a decreased peak and delayed TTP. The dynamic 4D-CT analysis suggested that organ perfusion changes according to balloon volume. The AUTDC at the PV, liver, and SMV decreased linearly with balloon inflation percentage to the maximum volume. 4D-VR demonstrated the delay of the washout in the aorta and retrograde flow at the inferior vena cava in the highly occluded status.

Production and rearing of germ-free X-SCID pigs

Pigs with X-linked severe combined immunodeficiency (X-SCID) caused by a mutation of the interleukin-2 receptor gamma chain gene (IL2RG) are of value for a wide range of studies. However, they do not survive longer than 8 weeks because of their susceptibility to infections. To allow longer survival of X-SCID pigs, the animals must be born and reared under germ-free conditions. Here, we established an efficient system for piglet derivation by hysterectomy and used it to obtain and maintain a germ-free X-SCID pig. In four trials using pregnant wild-type pigs, 66% of piglets after hysterectomy started spontaneous breathing (range of 20-100% per litter). The resuscitation rate was found to negatively correlate with elapsed time from the uterus excision to piglet derivation (r=-0.97, P<0.05). Therefore, it is critical to deliver piglets within 5 min to achieve a high resuscitation rate (82% estimated from regression analysis). In a fifth trial with an IL2RG^+/- pig, four piglets were delivered within 4.2 min of uterus excision and three were alive (75%). One of the live born piglets was genotypically and phenotypically determined to be X-SCID and was reared for 12 weeks. The X-SCID piglet was free from both bacteria and fungi at all time points tested by microbial culture and grew without any abnormal signs or symptoms. This study showed successful production and rearing of germ-free pigs, enabling experiments involving long-term follow-up of X-SCID pigs.

Ex-vivo and live animal models are equally effective training for the management of a penetrating cardiac injury

Background

Live tissue models are considered the most useful simulation for training in the management for hemostasis of penetrating injuries. However, these models are expensive, with limited opportunities for repetitive training. Ex-vivo models using tissue and a fluid pump are less expensive, allow repetitive training and respect ethical principles in animal research. The purpose of this study is to objectively evaluate the effectiveness of ex-vivo training with a pump, compared to live animal model training. Staff surgeons and residents were divided into live tissue training and ex-vivo training groups. Training in the management of a penetrating cardiac injury was conducted for each group, separately. One week later, all participants were formally evaluated in the management of a penetrating cardiac injury in a live animal.

Results

There are no differences between the two groups regarding average years of experience or previous trauma surgery experience. All participants achieved hemostasis, with no difference between the two groups in the Global Rating Scale score (ex-vivo: 25.2 ± 6.3, live: 24.7 ± 6.3, p = 0.646), blood loss (1.6 ± 0.7, 2.0 ± 0.6, p = 0.051), checklist score (3.7 ± 0.6, 3.6 ± 0.9, p = 0.189), or time required for repair (101 s ± 31, 107 s ± 15, p = 0.163), except overall evaluation (3.8 ± 0.9, 3.4 ± 0.9, p = 0.037). The internal consistency reliability and inter-rater reliability in the Global Rating Scale were excellent (0.966 and 0.953 / 0.719 and 0.784, respectively), and for the checklist were moderate (0.570 and 0.636 / 0.651 and 0.607, respectively). The validity is rated good for both the Global Rating Scale (Residents: 21.7 ± 5.6, Staff: 28.9 ± 4.7, p = 0.000) and checklist (Residents: 3.4 ± 0.9, Staff Surgeons: 3.9 ± 0.3, p = 0.003). The results of self-assessment questionnaires were similarly high (4.2–4.9) with scores in self-efficacy increased after training (pre: 1.7 ± 0.8, post: 3.2 ± 1.0, p = 0.000 in ex-vivo, pre: 1.9 ± 1.0, post: 3.7 ± 0.7, p = 0.000 in live). Scores comparing pre-training and post-evaluation (pre: 1.7 ± 0.8, post: 3.7 ± 0.9, p = 0.000 in ex-vivo, pre: 1.9 ± 1.0, post: 3.8 ± 0.7, p = 0.000 in live) were increased.

Conclusion

Training with an ex-vivo model and live tissue training are similar for the management of a penetrating cardiac injury, with increased self-efficacy of participants in both groups. The ex-vivo model is useful to learn hemostatic skills in trauma surgery.

Electronic supplementary material

The online version of this article (doi:10.1186/s13017-016-0104-3) contains supplementary material, which is available to authorized users.

Dorsal approach plus branch patch technique is the preferred method for liver transplanting small babies with monosegmental grafts

PURPOSE

When living donor liver transplantation (LDLT) is performed on small infant patients, the incidence of hepatic artery complications (HACs) is high. Here, we present a retrospective analysis that focuses on our surgical procedure for hepatic arterial reconstruction and the outcomes of monosegmental LDLT.

METHODS

Of the 275 patients who underwent LDLT between May 2001 and December 2015, 13 patients (4.7 %) underwent monosegmental LDLT. Hepatic artery reconstruction was performed under a microscope. The size discrepancy between the graft and the recipient's abdominal cavity was defined as the graft to recipient distance ratio (GRDR) between the left hepatic vein and the portal vein (PV) bifurcation on a preoperative computed tomography scan. HACs were defined as hepatic arterial hypoperfusion.

RESULTS

Recipient hepatic arteries were selected for the branch patch technique in five cases (38.5 %), and the diameter was 2.2 ± 0.6 mm. The anastomotic approaches selected were the dorsal position of the PV in seven cases (53.8 %) and the ventral position in six, and the GRDRs were 2.8 ± 0.4 and 1.9 ± 0.5, respectively (p = 0.012). The incidence rate of HACs caused by external factors, such as compression or inflammation around the anastomotic site, was significantly higher in monosegmental than in non-monosegmental graft recipients (15.4 vs. 1.1 %, p < 0.001).

CONCLUSION

Although monosegmental graft recipients experienced HACs caused by external factors around the anastomotic field, hepatic arterial reconstruction could be safely performed. Important components of successful hepatic arterial reconstructions include the employment of the branch patch technique and the selection of the dorsal approach.

A swine model of acute thrombocytopenia with prolonged bleeding time produced by busulfan

Animal models of thrombocytopenia are indispensable for evaluating the in vivo efficacy of hemostatic agents, cryopreserved platelets, and artificial platelets, but no large animal models are available. In this study, we generated a swine model of acute thrombocytopenia with prolonged bleeding times by administering the chemotherapeutic drug busulfan. First, we tested multiple doses of busulfan (4, 6, and 8 mg/kg) in pigs, and found that 6 mg/kg of busulfan is an optimal dose for producing a safe and moderate thrombocytopenia, with a platelet count of less than 30,000/µl. The pigs administered 6 mg/kg of busulfan (n=8) reached half their initial counts at day 7, counts below 30,000/µl at day 12, and their nadirs at day 15 (on average). The minimal platelet count was 14,000/µl. With this dose of busulfan (6 mg/kg), bleeding times were significantly prolonged in addition to the decrease in platelet counts (r=−0.63, P<0.01), while there were no cases of apparent hemorrhage. White blood cell counts were maintained at over 5,000/µl, and there were no infections or other adverse events including anemia or appetite or body weight loss. All pigs were sacrificed on day 16, with subsequent examination showing a significant reduction in cellularity and colony-forming units in the bone marrow, indicating that thrombocytopenia was the result of myelosuppression. In summary, administration with 6 mg/kg of busulfan induces safe and moderate thrombocytopenia with a prolonged bleeding time in swine.

Repetitive allogeneic intraarticular injections of synovial mesenchymal stem cells promote meniscus regeneration in a porcine massive meniscus defect model

OBJECTIVE

A new strategy is required in order to regenerate a meniscus for extensive defects. Synovial mesenchymal stem cells (MSCs) are an attractive cell source for meniscus regeneration due to their high proliferation and chondrogenic potential. We examined the effect of repetitive intraarticular injections of synovial MSCs on meniscus regeneration in a massive meniscal defect of pigs. We followed up the efficacy using MRI evaluation in addition to macroscopic and histological observations.

DESIGN

Two weeks before the injection of synovial MSCs, the anterior half of the medial menisci was resected in both knees of pigs. Fifty million allogeneic synovial MSCs were injected into the right knee at 0, 2, and 4 weeks and followed up by sequential MRI. The regenerated meniscus, adjacent articular cartilage, and subchondral bone were evaluated by MRI at 2, 4, 8, 12 and 16 weeks. They were also evaluated macroscopically and histologically at 16 weeks (n = 7).

RESULTS

The resected meniscus regenerated significantly better in the MSC group than in the control group based on histological and MRI analyses. Macroscopically, the meniscal defect already appeared to be filled with synovial tissue at 2 weeks. Articular cartilage and subchondral bone at the medial femoral condyle were also significantly more preserved in the MSC group based on MRI, macroscopic, and histological analyses.

CONCLUSIONS

Intraarticular injections of allogeneic synovial MSCs appeared to promote meniscus regeneration and provide protection at the medial femoral articular cartilage in a porcine massive meniscal defect model.

Risk factors and treatments for hepatic arterial complications in pediatric living donor liver transplantation

BACKGROUND

Hepatic artery complications (HAC) are a serious complication in pediatric liver transplant recipients because its incidence is high and it can occasionally lead to graft liver failure. We herein present a retrospective analysis of our 10-year experience with pediatric living donor liver transplantation (LDLT) focusing on the risk factors and treatments for HAC.

METHODS

Between May 2001 and November 2011, 209 LDLTs were performed for 203 pediatric recipients. We performed the multivariate analyses to identify the factors associated with HAC and showed the therapeutic strategy and outcome for HAC.

RESULTS

The overall incidence of HAC was 7.2%, and the graft survival of recipients with HAC was 73.3%. The multivariate analysis showed that the pediatric end-stage liver disease score (≥20), post-transplant laparotomy except for HAC treatment and extra-anatomical hepatic artery reconstruction were independent risk factors for HAC (P = 0.020, P = 0.015 and P = 0.002, respectively). Eleven surgical interventions and 13 endovascular interventions were performed for 15 recipients with HAC. The serum aspartate aminotransferase levels pre- and post-treatment for HAC were significantly higher in the surgical group than in the endovascular group (P = 0.016 and P = 0.022, respectively).

CONCLUSIONS

It is important for recipients with risk factors to maintain strict post-transplant management to help prevent HAC and detect it in earlier stages. Endovascular intervention can be a less invasive method for treating HAC than surgical intervention, and can be performed as an early treatment.

Portocaval shunt for hepatocyte package: challenging application of small intestinal graft in animal models

In developing therapeutic alternatives to liver transplantation, we have used the strategy of applying a small intestinal segment as a scaffold for hepatocyte transplantation and also as a portocaval shunt (PCS) system to address both liver dysfunction and portal hypertension. The aim of this study was to investigate the feasibility of such an intestinal segment in animal models. Hepatocytes isolated from luciferase-transgenic Lewis rats were transplanted into jejunal segments of wild-type Lewis rats with mucosa removal without PCS application. Luciferase-derived luminescence from transplanted hepatocytes was stably detected for 30 days. Then, we performed autologous hepatocyte transplantation into the submucosal layer of an isolated and vascularized small intestinal segment in pigs. Transplanted hepatocytes were isolated from the resected left-lateral lobe of the liver. On day 7, hepatocyte clusters and bile duct-like structures were observed histologically. To create an intestinal PCS system in pigs, an auto-graft of the segmental ileum and interposing vessel graft were anastomosed to the portal vein trunk and inferior vena cava. However, thrombi were observed in vessels of the intestinal PCSs. We measured the correlation between infusion pressure and flow volume in whole intestines ex vivo in both species and found that the high pressure corresponding to portal hypertension was still insufficient to maintain the patency of the intestinal grafts. In conclusion, we demonstrated the feasibility of the small intestine as a scaffold for hepatocyte transplantation in rat and pig models, but PCS using an intestinal graft failed to maintain patency in a pig model.

Cryo-preserved porcine kidneys are feasible for teaching and training renal biopsy: "the bento kidney"

BACKGROUND

The use of patients as the primary teaching modality for learning procedures is being questioned. While there have been advancements in the technology used for performing needle biopsies in both native and transplanted kidneys, there has been little advancement in teaching and training tools. We have developed a portable ex-vivo kidney, the Bento Kidney, using cryo-preserved porcine kidneys for teaching this procedure.

METHODS

The kidney is thawed, perfused by a pump, covered with skin for realistic haptic feedback, and then used with existing biopsy technology to teach the technique.

RESULTS

Thirty porcine kidneys were used in this pilot research, and nine were shipped to physicians at a distant facility. Renal biopsy was then performed using a core biopsy needle and ultrasound guidance. There was some leakage of fluid from all kidneys noted. All trainees felt that the model was realistic, and judged at a mean score of 8.7 (SD 0.8) on a scale of 1 (not useful) to 10 (very useful).

CONCLUSIONS

This feasibility study demonstrates that cryo-preserved porcine kidneys can be successfully used to teach and train renal biopsy techniques, and provides haptic feedback as well as realistic real-time ultrasound images. Further large scale studies are needed to demonstrate value from the educational point of view for nephrology and transplantation.

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.

Ex-vivo porcine organs with a circulation pump are effective for teaching hemostatic skills

Surgical residents have insufficient opportunites to learn basic hemostatic skills from clinical experience alone. We designed an ex-vivo training system using porcine organs and a circulation pump to teach hemostatic skills. Residents were surveyed before and after the training and showed significant improvement in their self-confidence (1.83 ± 1.05 vs 3.33 ± 0.87, P < 0.01) on a 5 point Likert scale. This training may be effective to educate residents in basic hemostatic skills.

Arthroscopic, histological and MRI analyses of cartilage repair after a minimally invasive method of transplantation of allogeneic synovial mesenchymal stromal cells into cartilage defects in pigs

BACKGROUND AIMS

Transplantation of synovial mesenchymal stromal cells (MSCs) may induce repair of cartilage defects. We transplanted synovial MSCs into cartilage defects using a simple method and investigated its usefulness and repair process in a pig model.

METHODS

The chondrogenic potential of the porcine MSCs was compared in vitro. Cartilage defects were created in both knees of seven pigs, and divided into MSCs treated and non-treated control knees. Synovial MSCs were injected into the defect, and the knee was kept immobilized for 10 min before wound closure. To visualize the actual delivery and adhesion of the cells, fluorescence-labeled synovial MSCs from transgenic green fluorescent protein (GFP) pig were injected into the defect in a subgroup of two pigs. In these two animals, the wounds were closed before MSCs were injected and observed for 10 min under arthroscopic control. The defects were analyzed sequentially arthroscopically, histologically and by magnetic resonance imaging (MRI) for 3 months.

RESULTS

Synovial MSCs had a higher chondrogenic potential in vitro than the other MSCs examined. Arthroscopic observations showed adhesion of synovial MSCs and membrane formation on the cartilage defects before cartilage repair. Quantification analyses for arthroscopy, histology and MRI revealed a better outcome in the MSC-treated knees than in the non-treated control knees.

CONCLUSIONS

Leaving a synovial MSC suspension in cartilage defects for 10 min made it possible for cells to adhere in the defect in a porcine cartilage defect model. The cartilage defect was first covered with membrane, then the cartilage matrix emerged after transplantation of synovial MSCs.

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.

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

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.

Pediatric living donor liver transplantation for biliary atresia with hepatopulmonary syndrome: the gift of a second wind

PURPOSE

Hepatopulmonary syndrome (HPS) is a progressive, deteriorating complication of end-stage liver disease (ESLD) that occurs in 13-47% of liver transplant candidates. Although LT is the only therapeutic option for HPS, it has a high morbidity and mortality, especially in patients with severe hypoxemia before transplantation, but the course of HPS after living donor liver transplantation (LDLT), especially for biliary atresia (BA) patients is not well established.

PATIENTS AND METHODS

The present study evaluated 122 patients who received an LDLT for BA and of these, 3 patients had HPS at the time of LDLT in a single-center series.

RESULTS

Two patients of the HPS patients them had biliary and/or vascular complications, but they recovered uneventfully with interventional treatment. None of the patients required supplemental oxygen and had no residual cardiopulmonary abnormalities at a follow-up of more than 24 months.

CONCLUSION

Although a series of three patients is too small for definitive conclusion and further investigations must be conducted, pediatric LDLT can be a favorable therapeutic option for HPS.

[Draft of Guidelines for Human Body Dissection for Clinical Anatomy Education and Research and commentary]

This article analyses the Draft of Guidelines for Human Body Dissection for Clinical Anatomy Education and Research drawn by the Study Group for Future Training Systems of Surgical Skills and Procedures established by the Fiscal Year 2010 research program of the Ministry of Health, Labor and Welfare. The purpose of the Draft of Guidelines is: First, to lay out the required basic guidelines for human cadaver usage to allow medical and dental faculty to conduct clinical education and research in accordance with existing regulations. Second, the guidelines are expected to give physicians a regulatory framework to carry out cadaver training in accordance with the current legal framework. This article explains the Draft of Guidelines in detail, outlines the future of cadaver training, and describes issues which must still be solved.

[Draft of guidelines for human body dissection for clinical anatomy education and research and commentary]

This article analyses the Draft of Guidelines for Human Body Dissection for Clinical Anatomy Education and Research drawn by the Study Group for Future Training Systems of Surgical Skills and Procedures established by the Fiscal Year 2010 research program of the Ministry of Health, Labor and Welfare. The purpose of the Draft of Guidelines is: First, to lay out the required basic guidelines for human cadaver usage to allow medical and dental faculty to conduct clinical education and research in accordance with existing regulations. Second, the guidelines are expected to give physicians a regulatory framework to carry out cadaver training in accordance with the current legal framework. This article explains the Draft of Guidelines in detail, outlines the future of cadaver training, and describes issues which must still be solved.

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 in 126 patients with biliary atresia: single-center experience

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.

Management of intra-abdominal drain after living donor liver transplantation

BACKGROUND

There have been few reports on the management of intra-abdominal drains after living donor liver transplantation (LDLT). We retrospectively investigated changes in ascitic data related to management of an intra-abdominal drain.

PATIENTS AND METHODS

Between March 2008 and June 2009, we performed 28 LDLT. On the first and the fifth postoperative day (POD) after LDLT, we examined the number of ascites cells and cell fractions as well as performed biochemical examination and cultures.

RESULTS

The day of removal of the drain for massive ascites (10 mL/kg/d or more) was 14.2 ± 5.4 POD; for less than 10 mL/kg/d it was 8.7 ± 1.9 POD (P < .001). Nine patients were ascites culture positive; long-term placement of the drain caused an infection in two patients.

CONCLUSIONS

When the amount of ascitic fluid on the fifth POD after LDLT was small, it was important to assess the properties of the ascitic fluid because of the possibility of a drain infection or of poor drainage. If the ascitic neutrophil count is less than 250/mm(3) or the examined ascites is normal, intra-abdominal drains should be removed.

Pediatric living donor liver transplantation using liver allograft with hemangioma

BACKGROUND

Although liver transplantation using liver allograft with hemangiomas has been previously reported, little is known about the fate of hemangiomas in the transplanted liver. We herein describe a case of pediatric living donor liver transplantation (LDLT) using living donor liver allograft with a hemangioma which is considered to the first reported case performing in vivo hemangioma resection.

CASE REPORT

A 27-year-old female was evaluated as a donor for her 2-year-old son with cholestatic cirrhosis due to biliary atresia. Preoperative ultrasonography and computed tomography revealed a 20-mm hemangioma located at lateral side of segment 3. During LDLT, an in vivo partial hepatic resection of the hemangioma of segment 3 was performed without the Pringle maneuver using intraoperative ultrasonography to keep the main portal triad of segment 3 before the donor liver resection, and the left lateral segment graft without the hemangioma, which underwent an intraoperative pathologic diagnosis, was transplanted into the recipient. The donor's postoperative course was uneventful and the recipient course was not observed subsequent liver necrosis, bleeding or bile leakage from the resection site.

CONCLUSIONS

Liver allografts with hemangiomas can be accepted as potential liver allografts, and such hemangiomas should undergo be performed in vivo resection during LDLT irrespective of tumor size.

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.

Double-balloon enteroscopy for bilioenteric anastomotic stricture after pediatric living donor liver transplantation

Bilioenteric anastomotic stricture after liver transplantation is still frequent and early detection and treatment is important. We established the management using double-balloon enteroscopy (DBE) and evaluated the intractability for bilioenteric anastomotic stricture after pediatric living donor liver transplantation (LDLT). We underwent DBE at Jichi Medical University from May 2003 to July 2009 for 25 patients who developed bilioenteric anastomotic stricture after pediatric LDLT. The patients were divided into two types according to the degree of dilatation of the anastomotic sites before and after interventional radiology (IVR) using DBE. Type I is an anastomotic site macroscopically dilated to five times or more, and Type II is an anastomotic site dilated to less than five times. The rate of DBE reaching the bilioenteric anastomotic sites was 68.0% (17/25), and the success rate of IVR was 88.2% (15/17). There were three cases of Type I and 12 cases of Type II. Type II had a significantly longer cold ischemic time and higher recurrence rate than Type I (P = 0.005 and P = 0.006). In conclusion, DBE is a less invasive and safe treatment method that is capable of reaching the bilioenteric anastomotic site after pediatric LDLT and enables IVR to be performed on strictures, and its treatment outcomes are improving. Type II and long cold ischemic time are risk factors for intractable bilioenteric anastomotic stricture.

Impact of acute cellular rejection on coagulation and fibrinolysis biomarkers within the immediate post-operative period in pediatric liver transplantation

We studied restoration of the coagulation and fibrinolysis system in pediatric patients following liver transplantation and biomarkers of blood coagulation and fibrinolysis for suspecting the occurrence of acute cellular rejection. Coagulation activity recovered rapidly within two days following transplantation, but it took approximately 21-28 days for full recovery of the coagulation and fibrinolysis factors synthesized in the liver. PAI-1 levels were significantly higher in patients at the time of acute cellular rejection compared with levels after control of AR, and levels on days 14 and 28 in patients without AR. Plasma protein C and plasminogen levels at the time of rejection were significantly lower than those on day 14 in patients without AR. Statistical analysis suggested that an increase in plasma PAI-1 at a single time point in the post-operative period is a reliable marker among the coagulation and fibrinolysis factors for suspecting the occurrence of acute cellular rejection. These data suggested that appropriate anticoagulation may be required for 14 days after liver transplantation in order to avoid vascular complications and measurement of plasma PAI-1 levels may be useful for suspecting the occurrence of acute cellular rejection in pediatric patients following liver transplantation.

Development of a portocaval shunt using a small intestinal segment in rats

The transjugular portosystemic shunt, widely used to treat portal hypertension today, may increase the risk of encephalopathy and reduce effective hepatic flow. To address these issues, a strategy to produce a portocaval shunt (PCS) with hepatic function using intestinal grafts was conceived, and rat models were developed. We transplanted ileal grafts from wild-type and luciferase transgenic Lewis rats to wild-type Lewis rats, anastomosing the graft mesenteric artery (SMA) and portal vein (PV) to the recipient PV trunk and inferior vena cava, respectively. Recipient survival was significantly longer in the partial PCS model, in which the graft SMA was anastomosed to the recipient PV trunk in an end-to-side fashion, than in the total PCS model, with the end-to-end anastomosis. In the partial PCS model, histological and luminescence analyses showed graft survival for 1 month. These results suggest that intestinal grafts can be maintained in the particular conditions required for our strategy.

Use of rat segmental intestine for fetal pancreatic transplantation

It is thought that the small intestine may provide a scaffold for pancreas regeneration. Herein, we investigated whether fetal pancreatic tissue could be transplanted into the segmental intestine in rats. Fetal pancreases from firefly luciferase transgenic Lewis rat embryos (embryonic day 14.5 and 15.5) were transplanted into streptozotocin (STZ)-induced diabetic wild-type Lewis rats. As a scaffold for pancreatic development, rat small intestinal segments were utilized after the removal of mucosa, and fetal pancreases were grafted into the luminal surface through the stoma. We also transplanted fetal pancreases into the omentum. The survival of transplanted fetal pancreases was monitored by luciferase-derived photons and blood glucose levels. Transplanted fetal pancreas-derived photons were stable for 28 days, suggesting that transplanted fetal pancreatic tissues survived and that their intestinal blood supply was maintained.

Mannequin Simulation Improves the Confidence of Medical Students Performing Tube Thoracostomy: A Prospective, Controlled Trial

This study was undertaken to determine the educational benefits of mannequin simulation for performance of tube thoracostomy in a porcine model by medical students. Thirty medical students were randomized into two groups; the first performed tube thoracostomy on a mannequin simulator and then a porcine model; the second used only the porcine model. Performance measures included completion of subtasks, time to perform the procedure, a global score assigned by faculty raters, and a self-evaluation survey. Subtask completion rate was similar in both groups ( P > 0.05). Mean time to perform the procedure was 9.8 minutes (±0.9, simulator), and 9.3 minutes (± 1.0, nonsimulator, P > 0.05). Global scores were 12.3 (±1.3, simulator) and 11.0 (±1.4, non-simulator, P > 0.05). Self-evaluation of confidence (1= “very”, 7= “not at all”) showed the simulator group was significantly more confident (3.4 ± 0.42) than the nonsimulator group (4.7 ± 0.49, P < 0.05). All students met basic competencies to perform tube thoracostomy. The simulator group felt significantly more confident to subsequently perform the procedure on a patient, whereas performance was not statistically significantly different for the two groups. Further trials may be needed to delineate the optimal role for these simulators in teaching tube thoracostomy.

Mannequin simulation improves the confidence of medical students performing tube thoracostomy: a prospective, controlled trial

This study was undertaken to determine the educational benefits of mannequin simulation for performance of tube thoracostomy in a porcine model by medical students. Thirty medical students were randomized into two groups; the first performed tube thoracostomy on a mannequin simulator and then a porcine model; the second used only the porcine model. Performance measures included completion of subtasks, time to perform the procedure, a global score assigned by faculty raters, and a self-evaluation survey. Subtask completion rate was similar in both groups (P > 0.05). Mean time to perform the procedure was 9.8 minutes (+/- 0.9, simulator), and 9.3 minutes (+/- 1.0, nonsimulator, P > 0.05). Global scores were 12.3 (+/- 1.3, simulator) and 11.0 (+/- 1.4, non-simulator, P > 0.05). Self-evaluation of confidence (1 = "very", 7 = "not at all") showed the simulator group was significantly more confident (3.4 +/- 0.42) than the nonsimulator group (4.7 +/- 0.49, P < 0.05). All students met basic competencies to perform tube thoracostomy. The simulator group felt significantly more confident to subsequently perform the procedure on a patient, whereas performance was not statistically significantly different for the two groups. Further trials may be needed to delineate the optimal role for these simulators in teaching tube thoracostomy.

Lymphocytotoxic crossmatch in pediatric living donor liver transplantation

To investigate the relationship between the pretransplant LCT results and the outcome after pediatric LDLT in a single center. The clinical data of 76 children undergoing 79 LDLTs including three retransplantations from May 2001 to January 2006 were retrospectively analyzed. All of the children had end-stage liver disease, and their median age was 1.4 yr (range, six months to 16.5 yr). Immunosuppressive therapy consisted of cyclosporine- or FK-based regimens with steroids. The children were classified into two groups (positive or negative) according to the pretransplant LCT results. The incidences of post-transplant surgical complications and of rejection episodes were compared. The relationship between the pretransplant LCT results and patient and graft survival rates was also analyzed. Seventy-nine pretransplant crossmatch tests were done; 13 (16.5%) were positive, and 66 (83.5%) were negative. No significant difference was found in the pretransplant clinical factors between two crossmatch groups. There was no significant difference between the groups in the incidence of vascular and biliary tract complications, in the rate of early or steroid-resistant cellular rejections, or in one- and three-yr patient (91.7%, 91.7%, respectively, in the positive group, 93.5%, 93.5%, respectively, in the negative group, p = 0.80) and graft (92.3%, 92.3%, respectively, in the positive group, 88.8%, 86.4%, respectively, in the negative group, p = 0.63) survival. The present study demonstrates that there is no reason to do pretransplant LCT to select the living donor for pediatric LDLT.

Paralysis in the left phrenic nerve after living-donor liver transplantation for biliary atresia with situs inversus

A 7-month-old boy with biliary atresia accompanied by situs inversus and absent inferior vena cava (IVC) underwent living-donor liver transplantation (LDLT). Because a constriction in the recipient hepatic vein (HV) was detected during the preparation of the HV in LDLT, a dissection in the cranial direction and a total clamp of the suprahepatic IVC was performed, and the suprahepatic IVC and the graft HV were anastomosed end-to-end. Postoperatively, atelectasis in the left upper lobe and ventilator failure accompanied by an elevation of the left hemidiaphragm were observed and mechanical ventilation was repetitively required. Paralysis in the left phrenic nerve was diagnosed by chest radiograph and ultrasonography. In our patient, conservative treatment was administrated, because weaning him from mechanical ventilation was possible a few days after intubation and the ventilator function was expected to be improved with growth. The disease course was good, and he was discharged from the hospital at 78 days after LDLT. Complications of paralysis in the phrenic nerve after cadaveric liver transplantation have been reported to be high. Although using a conventional technique during the reconstruction of the HV may injure the phrenic nerve directly, use of the piggyback technique with preservation of the IVC is rare. Even if LDLT was undertaken, a dissection of the HV or a total clamp of the suprahepatic IVC as a conventional technique can directly injure the phrenic nerve. Therefore, a dissection of the HV or a total clamp of the suprahepatic IVC at the reconstruction of the HV in LDLT should be carefully performed, and the possibility of paralysis in the phrenic nerve should be considered in patients with a relapse of respiratory symptoms and an elevation of the hemidiaphragm after LDLT.

Growth curves of pediatric patients with biliary atresia following living donor liver transplantation: factors that influence post-transplantation growth

We evaluated the growth curves of children with BA after LDLT, and identified factors influencing growth velocity one-yr after LDLT (DeltaZ). The clinical data of 51 children with BA, who had an LDLT at our center from 2001 to 2005, were retrospectively reviewed. The Z scores for height and weight, and DeltaZ were studied. The correlation between DeltaZ and various clinical factors was evaluated statistically. Multivariate stepwise analyses were performed for DeltaZ. The average height and weight Z scores at the time of LDLT were -1.34 +/- 1.36 (+/-s.d.) and -0.78 +/- 1.15, respectively. Among 30 BA recipients with stable liver function after transplant, weight returned to normal one-yr post-transplantation. However, height did not return to normal even by the third post-transplantation year. On multivariate analyses, 73% of the variance in height DeltaZ could be accounted for by factors such as standardized height at the time of LDLT (proportion of variance: 38%), number of steroid pulse treatments (17%), donor age (10%), and the presence of HVS (9%). Fifty-four percentage of the variance in weight DeltaZ could be accounted for by factors such as standardized weight at the time of LDLT (37%) and the total steroid dose given (17%). Height and weight status at the time of LDLT likely have the strongest impact on DeltaZ. Additional factors include steroid exposure, age of the living donor, and presence of HVS, all of which should be considered to improve post-transplantation growth.