Yoshihiro Hirata

Significance of serial real-time PCR monitoring of EBV genome load in living donor liver transplantation.

Background: Quantitative analysis of the Epstein–Barr virus (EBV) genome has been recently reported to be helpful for early identification of EBV viremia which could reduce the risk of post‐transplantation lymphoproliferative disorder (PTLD).

Effects of deuteriation on ZFS and sublevel decay rates of 3ππ* benzaldehyde

We have investigated deuterium effects on the ZFS and the sublevel decay rates of 3ππ* benzaldehyde in three different hosts. It was found that deuteriation of the formyl hydrogen reduces D considerably in acetophenone and 1,4-dichlorobenzene hosts. This effect is explained in terms of the changes in the 3ππ*-3 nπ* energy separations. The deuterium effect on the sublevel decay rate is likely due to two causes. (1) The ratio between the radiative decay rate constant (ki r ) and the radiationless decay rate constant (ki n ) is dependent on the sublevel. (2) ki n is sublevel dependent. The deuterium effect on kz n is shown to be very large in 3ππ* benzaldehyde. The deuteriation of formyl hydrogen predominantly affects kz n which indicates, as predicted by Kanamaru and Lim, that 3ππ*-3 nπ* vibronic mixing is the most important mechanism in causing the radiationless decay. The correlation between the z sublevel decay rate constant (kz ) and ΔETT found for a series of benzaldehydes is discussed in the light of ...

Novel technique for pediatric living donor liver transplantation in patients with portal vein obstruction: The “pullout technique”

PV hypoplasia may increase the risk of posttransplant complications, especially when it extends to near the SMV and SpV junction. We described our experience of 10 pediatric cases of PV hypoplasia/thrombus in which the pullout technique was required for PV reconstruction. There were five male and five female patients. The median age was 9 months, and the median weight was 8.1 kg. The indications for the pullout technique were PV hypoplasia in seven patients and PV thrombus in 3. The inflow sites of the enlarged LGV were as follows: the main PV trunk (n = 2), the SMV and SpV junction (n = 4), and the SpV (n = 4). The posterior face of the pancreas was tunneled along the PV, and the PV was returned to its original position with or without the use of an interposed vein graft. The pullout technique created a good operative field, which allowed for the complete removal of the hypoplastic PV or thrombectomy with the safe use of various interposed vein grafts.

Modified triangular hepatic vein reconstruction for preventing hepatic venous outflow obstruction in pediatric living donor liver transplantation using left lateral segment grafts

HVOO can be a critical complication in pediatric LDLT. The aim of this study was to evaluate a modified triangular technique of hepatic vein reconstruction for preventing HVOO in pediatric LDLT. A total of 298 pediatric LDLTs were performed using a left lateral segment graft by 2 methods for reconstruction of the hepatic vein. In 177 recipients, slit‐shaped anastomosis was indicated with partial clamp of the IVC. A total of 121 recipients subjected to the modified triangular anastomosis with total clamp of the IVC. We compared the incidence of hepatic vein anastomotic complications between these 2 methods. Nine of the 177 cases (5.3%) treated with the conventional technique were diagnosed with outflow obstruction. All 9 cases underwent hepatic vein reconstruction with the slit‐shaped hepatic vein anastomosis. In contrast, there were no cases of outflow obstruction in the 121 cases treated with the modified triangular anastomosis. The modified triangular technique of hepatic vein reconstruction with total clamping of the IVC was useful for preventing HVOO in pediatric LDLT.

Impact of graft thickness reduction of left lateral segment on outcomes following pediatric living donor liver transplantation

Reducing graft thickness is essential to prevent large‐for‐size graft problems in pediatric living donor liver transplantation (LDLT). However, long‐term outcomes of LDLT using reduced‐thickness left lateral segment (LLS) grafts are unclear. In 89 patients who underwent LDLT using reduced LLS grafts between 2005 and 2017, short‐term and long‐term outcomes were compared between a nonanatomically reduced LLS (NAR‐LLS) graft group and a reduced‐thickness LLS graft group. Estimated blood loss was lower and abdominal skin closure was less needed in the recipient operation in the reduced‐thickness LLS graft group. Postoperatively, portal vein (PV) flow was significantly decreased in the NAR‐LLS graft group, and there was shorter intensive care unit (ICU) stay and fewer postoperative complications, especially bacteremia, in the reduced‐thickness LLS graft group. Graft survival at 1 and 3 years after LDLT using reduced‐thickness LLS grafts was 95.2% and 92.4%, respectively, which was significantly better than for NAR‐LLS grafts. Multivariate analysis revealed that fulminant liver failure, hepatofugal PV flow before LDLT, and NAR‐LLS graft were associated with poor graft survival. In conclusion, LDLT using reduced‐thickness LLS grafts is a safe and feasible option with better short‐ and long‐term outcomes in comparison with NAR‐LLS grafts.

Impact of antibodies that react with liver tissue and donor-specific anti-HLA antibodies in pediatric idiopathic posttransplantation hepatitis

Background The cause of late graft dysfunction has not been elucidated. Although an antibody-mediated reaction is suspected as a potential mechanism, the target antigens have not been clarified. Methods To clarify the etiology of idiopathic posttransplantation hepatitis (IPTH), we simultaneously examined the presence of antibodies that react with liver tissue (ARLT) by means of indirect immunofluorescence staining, as well as the presence of donor-specific anti-human leukocyte antigen antibodies (HLA-DSA). A subanalysis of the IPTH group was also performed. Within the IPTH group, the correlation between ARLT titer and clinical data were analyzed. Results In the sera of patients with IPTH (30 patients), ARLT were found at a significantly higher frequency than in patients without IPTH (42 patients; P < 0.001). Moreover, the ARLT titer appeared to be correlated with the severity of hepatitis or hepatic injury. In contrast, the frequency of HLA-DSA was significantly lower in patients with IPTH than in patients without IPTH (P = 0.001). Conclusion Our findings indicate that ARLT, and not HLA-DSA, profoundly influence the etiology of IPTH.