Antitumor effects of chemically modified miR-143 lipoplexes in a mouse model of pelvic colorectal cancer via myristoylated alanine-rich C kinase substrate downregulation

Replenishing tumor-suppressor miRNAs (TS-miRNAs) is a potential next-generation nucleic acid-based therapeutic approach. Establishing an effective miRNA delivery system is essential to successful TS-miRNA therapy. To overcome vulnerability to RNA nucleases, we previously developed a chemically modified miRNA143-3p (CM-miR-143). In clinical practice, colorectal cancer (CRC) pelvic recurrence is an occasional challenge following curative resection, requiring a novel therapy because reoperative surgery poses a significant burden to the patient. Hence, we considered the use of CM-miR-143 as an alternative treatment. In this study, we used a mouse model bearing pelvic CRC adjacent to the rectum and investigated the anticancer effects of CM-miR-143 lipoplexes formulated from miRNA and a cationic liposome. Compared with commercial synthetic miR-143, CM-miR-143 lipoplexes accumulated heavily in regions of the pelvic CRC tumor where the blood flow was high. As a result, systemic administration of CM-miR-143 lipoplexes improved animal survival by significantly suppressing pelvic CRC tumors and relieving a lethal bowel obstruction caused by rectal compression. Detailed protein analysis revealed that the myristoylated alanine-rich C kinase is a novel target for CM-miR-143 lipoplexes. Our results suggest that CM-miR-143 is a potential next-generation drug candidate in the treatment of CRC pelvic recurrence.

Anti-tumor effect of boron neutron capture therapy in pelvic human colorectal cancer in a mouse model

Local recurrence of colorectal cancer (CRC) can occur in patients after curative resection, and additional surgical resection may therefore be required; however, this is a significant burden for patients, because additional surgical resection may necessitate the resection of other organs such as the bladder, prostate, uterus, or sacral bone. Therefore, there is a need for alternative therapeutic strategies. We focused on boron neutron capture therapy (BNCT) as a treatment modality that can selectively target tumor cells without excessive damage to normal tissues. The usefulness of BNCT to pelvic CRC remains unknown. This study investigated the anti-cancer effect of boronophenylalanine (BPA)-mediated BNCT in a previously established mouse model of pelvic recurrence of CRC. Uptake of BPA in CRC was observed both in vitro and in vivo, and the concentrations were sufficient for BNCT. Our results are the first to show that BPA-mediated BNCT prolonged the survival of experimental mice with pelvic tumors; moreover, it did not cause any obvious severe side effects in the treated animals. In conclusion, BPA-mediated BNCT could contribute to treating local recurrence of pelvic CRC.

Glucose transporter‑1 inhibition overcomes imatinib resistance in gastrointestinal stromal tumor cells

Imatinib mesylate (imatinib) is the primary agent of choice used to treat gastrointestinal stromal tumors (GIST). However, drug resistance to imatinib poses a major obstacle to treatment efficacy. In addition, the relationship between imatinib resistance and glycolysis is poorly understood. Glucose transporter (GLUT)-1 is a key component of glycolysis. The present study aimed to assess the potential relationship between components in the glycolytic pathway and the acquisition of imatinib resistance by GIST cells, with particular focus on GLUT-1. An imatinib-resistant GIST cell line was established through the gradual and continuous imatinib treatment of the parental human GIST cell line GIST-T1. The expression of glycolysis-related molecules (GLUT-1, hexokinase 2, pyruvate kinase M2 and lactate dehydrogenase) was assessed in parental and imatinib-resistant cells by western blotting, reverse transcription-quantitative PCR and glucose and lactate measurement kits. In addition, clinical information and transcriptomic data obtained from the gene expression omnibus database (GSE15966) were used to confirm the in vitro results. The potential effects of GLUT-1 inhibition on the expression of proteins in the glycolysis (GLUT-1, hexokinase 2, pyruvate kinase M2 and lactate dehydrogenase) and apoptosis pathways (Bcl-2, cleaved PARP, caspase-3 and caspase-9) in imatinib-resistant cells were then investigated following gene silencing and treatment using the GLUT-1 inhibitor WZB117 by western blotting. For gene silencing, the mature siRNAs for SLC2A1 were used for cell transfection. Annexin V-FITC/PI double-staining followed by flow cytometry was used to measure apoptosis whereas three-dimensional culture experiments were used to create three-dimensional spheroid cells where cell viability and spheroid diameter were measured. Although imatinib treatment downregulated GLUT-1 expression and other glycolysis pathway components hexokinase 2, pyruvate kinase M2, and lactate dehydrogenase in parental GIST-T1 cells even at low concentrations. By contrast, expression of these glycolysis pathway components in imatinib-resistant cells were increased by imatinib treatment. WZB117 administration significantly downregulated AKT phosphorylation and Bcl-2 expression in imatinib-resistant cells, whereas the combined administration of imatinib and WZB117 conferred synergistic growth inhibition effects in apoptosis assay. WZB117 was found to exert additional inhibitory effects by inducing apoptosis in imatinib-resistant cells. Therefore, the present study suggests that GLUT-1 is involved in the acquisition of imatinib resistance by GIST cells, which can be overcome by combined treatment with WZB117 and imatinib.

Delta-like canonical Notch ligand 3 as a potential therapeutic target in malignancies: A brief overview

Delta‐like canonical Notch ligand 3 (DLL3) is a member of the Delta/Serrate/Lag2 (DSL) Notch receptor ligand family and plays a crucial role in Notch signaling, which influences various cellular processes including differentiation, proliferation, survival, and apoptosis. DLL3 is expressed throughout the presomitic mesoderm and is localized to the rostral somatic compartments; mutations in DLL3 induce skeletal abnormalities such as spondylocostal dysostosis. Recently, DLL3 has attracted interest as a novel molecular target due to its high expression in neuroendocrine carcinoma of the lung. Moreover, a DLL3‐targeting Ab‐drug conjugate, rovalpituzumab tesirine (ROVA‐T), has been developed as a new treatment with proven antitumor activity. However, the development of ROVA‐T was suspended because of shorter overall survival compared to topotecan, the second‐line standard treatment. Thus, several studies on the mechanism and function of DLL3 in several malignancies are underway to find a new strategy for targeting DLL3. In this review, we discuss the roles of DLL3 in various malignancies and the future perspectives of DLL3‐related research, especially as a therapeutic target.

Uptake of MicroRNAs from Exosome-Like Nanovesicles of Edible Plant Juice by Rat Enterocytes

MicroRNAs (miRNAs) are small RNAs present in extracellular vesicles (EVs) that, when transferred to a target cell, affect its biological functions. Plant miRNAs regulate the expression of certain mammalian genes. Here, we characterized EVs in fruit and vegetable juice, and their miRNA cargo, and investigated whether such miRNA-containing EVs could be taken up by mammalian enterocytes in vitro. Using filtration and ultra-centrifugation methods, EVs were purified from commercially available and manually squeezed plant juice. EV morphological features and subcellular localization were analyzed using the NanoSight tracking system and electron microscopy. Plant EV miRNA levels were evaluated using quantitative reverse transcription PCR. For the in vitro EV uptake experiments, rat intestinal epithelial cells (IEC6) were used. Plant EVs shared morphological features with mammalian EVs and contained miR156a-5p, miR166a-3p, and miR168a-5p. EVs were present in the cell sap-filled central vacuoles and were taken up by IEC6 cells. Edible plant cells produce EVs that contain various miRNAs and release them into the central vacuole. The exogenous plant EVs are taken up by mammalian enterocytes in vitro. These findings suggest the possibility that exogenous plant miRNAs carried by EVs can be absorbed via the gastrointestinal tract.

Evaluation of lymphatic flow pattern using indocyanine green fluorescence imaging in a highly metastatic mouse model

Recently, the feasibility of real‐time indocyanine green (ICG) fluorescence imaging–guided complete mesocolic excision in colon cancer surgery has been demonstrated; however, its application to the evaluation of lymphatic flow in widespread lymph node metastasis is uncertain. This study aimed to evaluate lymphatic flow using the real‐time ICG fluorescence imaging. A mouse model of subcutaneous inoculation of BJMC3879Luc2 cells, which have been demonstrated to highly metastasize to the lymph nodes, was used as an evaluation model. Tumor growth and lymphatic flow were monitored weekly by bioluminescent imaging and near‐infrared (NIR) fluorescence imaging, respectively. After sacrificing the mice, lymph node metastases were evaluated by bioluminescent imaging and histopathology. Lymphatic flows in a model of high lymph node metastasis were evaluated using NIR fluorescence imaging. Pathological metastases of bilateral axillary, femoral, and para‐aortic lymph nodes were detected in all inoculated mice (100%: 5/5). Real‐time NIR fluorescence imaging showed the primary lymphatic vessels staining through the metastatic lymph nodes as before the inoculation of the cancer cells. Hitherto, it has been considered that lymphatic flow was changed using the bypass pathway due to occlusion of the primary lymphatic vessels. In this presented study, real‐time ICG fluorescence imaging showed no changes in lymphatic flow after lymph node metastasis. Our results suggest that real‐time ICG fluorescence imaging may have potential for the guidance of colon cancer surgery in cases of widespread lymph node metastasis.

γ-H2AX as a potential indicator of radiosensitivity in colorectal cancer cells

Preoperative radiotherapy improves local disease control and disease-free survival in patients with advanced rectal cancer; however, a reliable predictive biomarker for the effectiveness of irradiation has yet to be elucidated. Phosphorylation of H2A histone family member X (H2AX) to γ-H2AX is induced by DNA double-strand breaks and is associated with the development of colorectal cancer (CRC). The current study aimed to clarify the relationship between γ-H2AX expression and CRC radiosensitivity in vitro and in vivo. H2AX levels were analyzed in datasets obtained from cohort studies and γ-H2AX expression was investigated by performing immunohistochemistry and western blotting using clinical CRC samples from patients without any preoperative therapy. In addition, the CRC cell lines WiDr and DLD-1 were subjected to irradiation and/or small interfering RNA-H2AX, after which the protein levels of γ-H2AX were examined in samples obtained from patients undergoing preoperative chemoradiotherapy. To quantify the observable effect of treatment on cancer cells, outcomes were graded as follows: 1, mild; 2, moderate; and 3, marked, with defined signatures of cellular response. Datasets obtained from cohort studies demonstrated that H2AX mRNA levels were significantly upregulated and associated with distal metastasis and microsatellite instability in CRC tissues, in contrast to that of normal tissues. In addition, γ-H2AX was overexpressed in clinical samples. In vitro, following irradiation, γ-H2AX expression levels increased and cell viability decreased in a time-dependent manner. Combined irradiation and γ-H2AX knockdown reduced the viability of each cell line when compared with irradiation or γ-H2AX knockdown alone. Furthermore, among clinical CRC samples from patients undergoing preoperative chemoradiotherapy, levels of γ-H2AX in the grade 1 group were significantly higher than those in grade 2 or grade 3. In conclusion, γ-H2AX may serve as a novel predictive marker and target for preoperative radiotherapy effectiveness in patients with CRC.

Ki67 expression at Kasai portoenterostomy as a prognostic factor in patients with biliary atresia

Background

Biliary atresia is a rare paediatric biliary obliteration disease with unknown aetiology, and is the most common indication for paediatric liver transplantation (LT). However, no consensus for predicting Kasai portoenterostomy (KP) outcomes using liver histological findings exists. Ki67 is a popular biomarker for measuring and monitoring cellular proliferation.

Methods

Ki67 (clone, MIB‐1) liver parenchyma expression was measured by immunohistochemical staining of samples from living donors and patients with biliary atresia to assess its value in predicting outcomes after KP.

Results

Of 35 children with biliary atresia, 13 were native liver survivors (NLS), 17 were non‐NLS, and five had primary LT. The median proportion of Ki67 immunostained areas in donors and patients with biliary atresia at KP was 0·06 and 0·99 per cent respectively. Univariable analysis identified a high proportion of Ki67 areas, high Ki67 cell numbers and high Ki67‐positive/leucocyte common antigen‐positive cell numbers at KP as significant predictors of poor native liver survival after KP (hazard ratio 9·29, 3·37 and 12·17 respectively). The proportion of Ki67 areas in the non‐NLS group was significantly higher than that in the NLS group (1·29 versus 0·72 per cent respectively; P = 0·001), and then decreased at LT (0·32 per cent versus 1·29 per cent at KP; P < 0·001).

Conclusion

This study has demonstrated the clinical data and time course of Ki67 expression in patients with biliary atresia. High Ki67 expression at KP may be an important predictor of native liver survival following the procedure.

Estimating transboundary transported anthropogenic sulfate deposition in Japan using the sulfur isotopic ratio

High emissions of air pollutants from Northeast Asia are strongly influenced by air quality as well as by ecosystems. This study investigated the spatiotemporal variations in the sulfur isotopic ratio (δ³⁴S) in atmospheric deposition at eleven monitoring stations in Japan from 2011 to 2016 and estimated the amount of transboundary transported anthropogenic sulfate (TRB) deposition using mass balance calculations. The δ³⁴S of sulfate in precipitation ranged from -0.42 to +22.7‰. Sea salt (SS), TRB, and domestic anthropogenic sources (DOM) were the dominant sources of sulfate deposition in Japan. TRB sulfate deposition was largest on the Sea of Japan side, with an annual average value of 1.5 ± 0.3-6.9 ± 0.5 mg m^-2 d^-1 (36-44%), followed by Mt. Happo (4.5 ± 0.1 mg m^-2 d^-1; 88%), the Pacific Ocean side (1.5 ± 0.8, 4.3 ± 0.9 mg m^-2 d^-1; 24-50%), and the remote islands in the North Pacific Ocean (1.1 ± 0.2, 2.0 ± 0.8 mg m^-2 d^-1; 19-32%). TRB sulfate deposition on the Sea of Japan side was 2-12 times higher in winter and 1-2 times higher in summer than that of DOM. In contrast, TRB sulfate deposition on the Pacific Ocean side was 1.5-3 times higher in summer than in winter due to high precipitation levels. In Tokyo, the annual contribution from DOM sulfate deposition is approximately three times higher than that from TRB. Annual TRB sulfate deposition is lowest at Ogasawara at 1.1 ± 0.2 mg m^-2 d^-1, and the annual oceanic DMS contribution to sulfate deposition is high, accounting for 1.3 mg m^-2 d^-1 (20 ± 6%). The contribution of Asian dust was estimated to be 1-5.2 mg m^-2 d^-1(3-6%), which occurred in a single Asian dust event on the Sea of Japan side.

α-Aminoisobutyric Acid-Containing Amphipathic Helical Peptide-Cyclic RGD Conjugation as a Potential Drug Delivery System for MicroRNA Replacement Therapy in Vitro

Replacement therapy with tumor suppressive microRNA (TS-miRNA) might be the next-generation oligonucleotide therapy; however, a novel drug delivery system (DDS) is required. Recently, we developed the cell-penetrating peptide, model amphipathic peptide with α-aminoisobutyric acid (MAP(Aib)), as a carrier for oligonucleotide delivery to cells. In this study, we examined whether a modified MAP(Aib) analogue, MAP(Aib)-cRGD, could be a DDS for TS-miRNA replacement therapy. MIR145-5p, a representative TS-miRNA especially in colorectal cancer, was selected. The MAP(Aib)-cRGD dose was adjusted for MIR145-5p delivery to cells using peripheral blood mononuclear cells and degradation analysis. AlexaFluor488-labeled MIR145-5p incorporation into cells and negative regulation of MIR145-5p-targeting genes demonstrated MAP(Aib)-cRGD's functionality as a miRNA DDS. Treating MIR145-5p with MAP(Aib)-cRGD also revealed various anticancer effects, such as cell viability, invasion inhibition, and apoptosis induction in WiDr cells. Altogether, these findings suggest that MAP(Aib)-cRGD could be a DDS for TS-miRNA replacement therapy, but in vivo investigations are required.

Delta-like 3 localizes to neuroendocrine cells and plays a pivotal role in gastrointestinal neuroendocrine malignancy

Delta‐like 3 (DLL3) is a member of the Delta/Serrate/Lag2 (DSL) group of Notch receptor ligands. Five DSL ligands are known in mammals, among which DLL3 has a unique structure. In the last few years, DLL3 has attracted attention as a novel molecular targeting gene in neuroendocrine carcinoma of the lung due to its high expression. However, the expression pattern and functions of DLL3 in the gastrointestinal tract and gastrointestinal neuroendocrine carcinoma remain unclear. In this study, we examined the expression and role of DLL3 in the gastrointestinal tract, as well as in gastrointestinal neuroendocrine carcinoma. Immunohistochemical staining of the human normal gastrointestinal tract revealed that DLL3 localized in neuroendocrine cells. DLL3 showed intense staining in chromogranin A‐positive gastric cancer specimens. Real‐time quantitative RT‐PCR and western blotting analyses showed considerable upregulation of DLL3 in gastrointestinal neuroendocrine carcinoma cell lines. Immuno‐electron microscopy demonstrated abundant expression of DLL3 in neurosecretory granules in these cells. Furthermore, gene silencing of DLL3 caused significant growth inhibition through the induction of intrinsic apoptosis. Our findings suggest that DLL3 is expressed in neuroendocrine cells of the gastrointestinal tract and that it has a pivotal role in gastrointestinal neuroendocrine carcinoma cells. Based on these findings, further investigations are required to achieve a breakthrough in developing therapeutic strategies for gastrointestinal neuroendocrine carcinoma.

Estimate of Fukushima-derived radiocaesium in the North Pacific Ocean in summer 2012

Distributions of radiocaesium (134Cs and 137Cs) derived from the Tokyo Electric Power Company (TEPCO) Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident in the North Pacific Ocean in the summer of 2012 were investigated. We have estimated the radiocaesium inventory in the surface layer using the optimal interpolation analysis and the subducted amount into the central mode water (CMW) by using vertical profiles of FNPP1-134Cs and mass balance analysis as the first approach. The inventory of the 134Cs in the surface layer in the North Pacific Ocean in August-December 2012 was estimated at 5.1 ± 0.9 PBq on 1 October 2012, which corresponds to 8.6 ± 1.5 PBq when it was decay corrected to the date of the FNPP1 accident, 11 March 2011. It was revealed that 56 ± 10% of the released 134Cs into the North Pacific Ocean, which was estimated at 15.3 ± 2.6 PBq, transported eastward in the surface layer in 2012. The amount of 134Cs subducted in the CMW was estimated to be 2.5 ± 0.9 PBq based on the mass balance among the three domains of the surface layer, subtropical mode water, and CMW.

Organ-Specific MicroRNAs (MIR122, 137, and 206) Contribute to Tissue Characteristics and Carcinogenesis by Regulating Pyruvate Kinase M1/2 (PKM) Expression

Pyruvate kinase is known as the glycolytic enzyme catalyzing the final step in glycolysis. In mammals, two different forms of it exist, i.e., pyruvate kinase M1/2 (PKM) and pyruvate kinase L/R (PKLR). Also, PKM has two isoforms, i.e., PKM1 and PKM2. These genes have tissue-specific distribution. Namely, PKM1 is distributed in high-energy-demanding organs, such as brain and muscle. Also, PKM2 is distributed in various other organs, such as the colon. On the other hand, PKLR is distributed in liver and red blood cells (RBCs). Interestingly, PKM2 has been recognized as one of the essential genes for the cancer-specific energy metabolism termed the “Warburg effect”. However, the mechanism(s) underlying this fact have remained largely unclear. Recently, we found that some organ-specific microRNAs (miRNAs, MIR) regulate PKM isoform expression through direct targeting of polypyrimidine tract binding protein 1 (PTBP1), which is the splicer responsible for PKM2-dominant expression. In this study, we examined whether this machinery was conserved in the case of other PTBP1- and PKM-targeting miRNAs. We focused on the MIRs 122, 137, and 206, and investigated the expression profiles of each of these miRNAs in tissues from mouse and human organs. Also, we examined the regulatory mechanisms of PKM isoform expression by testing each of these miRNAs in human cancer cell lines. Presently, we found that brain-specific MIR137 and muscle-specific MIR206 predominantly induced PKM1 expression through direct targeting of PTBP1. Also, liver-specific MIR122 suppressed the expression of both PKM1 and PKM2, which action occurred through direct targeting of PKM to enable the expression of PKLR. Moreover, the expression levels of these miRNAs were downregulated in cancer cells that had originated from these tissues, resulting in PKM2 dominance. Our results suggest that the organ-specific distribution of miRNAs is one of the principal means by which miRNA establishes characteristics of a tissue and that dysregulation of these miRNAs results in cancer development through a change in the ratio of PKM isoform expression. Also, our results contribute to cancer diagnosis and will be useful for cancer-specific therapy for the Warburg effect in the near future.

Living Donor Liver Transplantation for Progressive Familial Intrahepatic Cholestasis Type 1: Two Reported Cases

BACKGROUND

Progressive familial intrahepatic cholestasis type 1 (PFIC1) is an inherited disease characterized by cholestatic features. We report two patients with PFIC1 who underwent liver retransplantation.

CASE REPORT

One patient was a 3-year-old female who underwent liver transplantation for PFIC1. She presented with severe diarrhea and fatty liver, and went into liver failure. She therefore underwent liver retransplantation and external biliary diversion 8 years after the initial liver transplantation. The explanted liver was histologically diagnosed with chronic rejection. Her intractable diarrhea stopped after the retransplantation. She was diagnosed with a fatty liver 8 months after the retransplantation and died 4 years after retransplantation due to bleeding from an ileostomy. The other patient was a 3-year-old male. This patient underwent liver retransplantation due to liver cirrhosis caused by steatohepatitis 9 years after the initial liver transplantation. The biliary tract was not diverted. He also experienced severe diarrhea after the retransplantation and requires home parenteral nutrition due to an eating disorder.

CONCLUSIONS

Liver transplantation is the only treatment to resolve life-threatening issues due to PFIC1, but requires further improvement as a therapeutic modality.

Spatial and temporal distributions of (134)Cs and (137)Cs derived from the TEPCO Fukushima Daiichi Nuclear Power Plant accident in the North Pacific Ocean by using optimal interpolation analysis

Optimal interpolation (OI) analysis was used to investigate the oceanic distributions of (134)Cs and (137)Cs released from the Tokyo Electric Power Company Fukushima Daiichi Nuclear Power Plant (FNPP1) accident. From the end of March to early April 2011, extremely high activities were observed in the coastal surface seawater near the FNPP1. The high activities spread to a region near 165°E in the western North Pacific Ocean, with a latitudinal center of 40°N. Atmospheric deposition also caused high activities in the region between 180° and 130°W in the North Pacific Ocean. The inventory of FNPP1-released (134)Cs in the North Pacific Ocean was estimated to be 15.3 ± 2.6 PBq. About half of this activity (8.4 ± 2.6 PBq) was found in the coastal region near the FNPP1. After 6 April 2011, when major direct releases ceased, the FNPP1-released (134)Cs in the coastal region decreased exponentially with an apparent half-time of about 4.2 ± 0.5 days and declined to about 2 ± 0.4 PBq by the middle of May 2011. Taking into account that the (134)Cs/(137)Cs activity ratio was about 1 just after release and was extremely uniform during the first month after the accident, the amount of (137)Cs released by the FNPP1 accident increased the North Pacific inventory of (137)Cs due to bomb testing during the 1950s and early 1960s by 20%.

LPA signaling initiates schizophrenia-like brain and behavioral changes in a mouse model of prenatal brain hemorrhage

Genetic, environmental and neurodevelopmental factors are thought to underlie the onset of neuropsychiatric disorders such as schizophrenia. How these risk factors collectively contribute to pathology is unclear. Here, we present a mouse model of prenatal intracerebral hemorrhage--an identified risk factor for schizophrenia--using a serum-exposure paradigm. This model exhibits behavioral, neurochemical and schizophrenia-related gene expression alterations in adult females. Behavioral alterations in amphetamine-induced locomotion, prepulse inhibition, thigmotaxis and social interaction--in addition to increases in tyrosine hydroxylase-positive dopaminergic cells in the substantia nigra and ventral tegmental area and decreases in parvalbumin-positive cells in the prefrontal cortex--were induced upon prenatal serum exposure. Lysophosphatidic acid (LPA), a lipid component of serum, was identified as a key molecular initiator of schizophrenia-like sequelae induced by serum. Prenatal exposure to LPA alone phenocopied many of the schizophrenia-like alterations seen in the serum model, whereas pretreatment with an antagonist against the LPA receptor subtype LPA1 prevented many of the behavioral and neurochemical alterations. In addition, both prenatal serum and LPA exposure altered the expression of many genes and pathways related to schizophrenia, including the expression of Grin2b, Slc17a7 and Grid1. These findings demonstrate that aberrant LPA receptor signaling associated with fetal brain hemorrhage may contribute to the development of some neuropsychiatric disorders.

Long-term outcomes of pediatric living donor liver transplantation in Japan: an analysis of more than 2200 cases listed in the registry of the Japanese Liver Transplantation Society

The Japanese Liver Transplantation Society (JLTS) was established in 1980 in order to characterize and follow trends in patient characteristics and graft survival among all liver transplant patients in Japan. This study analyzed the comprehensive factors that may influence the outcomes of pediatric patients who undergo living donor liver transplantation (LDLT) by evaluating the largest cohort in the world. Between November 1989 and December 2010, 2224 pediatric patients underwent LDLT in Japan. There were 998 male (44.9%) and 1226 female donors (55.1%) without donor mortalities related to transplant surgery. There were 946 male (42.5%) and 1278 female (57.5%) recipients with a median age of 4.0 years (range: 13 days to 17.9 years). Cholestatic liver disease was the leading indication for LDLT (n = 1649; 76.2%), followed by metabolic disorders (n = 194; 8.7%), acute liver failure (n = 192; 8.6%) and neoplastic liver disease (n = 66; 3.0%). The 1-, 5-, 10- and 20-year patient survival rates were 88.3%, 85.4%, 82.8% and 79.6%, respectively. Blood-type incompatibility, recipient age, etiology of liver disease and transplant era were found to be significant predictors of overall survival. We are able to achieve satisfactory long-term pediatric patient survival outcomes in the JLTS series without compromising the living donors.

Optimum interpolation analysis of basin-scale ¹³⁷Cs transport in surface seawater in the North Pacific Ocean

¹³⁷Cs is one of the conservative tracers applied to the study of oceanic circulation processes on decadal time scales. To investigate the spatial distribution and the temporal variation of ¹³⁷Cs concentrations in surface seawater in the North Pacific Ocean after 1957, a technique for optimum interpolation (OI) was applied to understand the behaviour of ¹³⁷Cs that revealed the basin-scale circulation of Cs ¹³⁷Cs in surface seawater in the North Pacific Ocean: ¹³⁷Cs deposited in the western North Pacific Ocean from global fallout (late 1950s and early 1960s) and from local fallout (transported from the Bikini and Enewetak Atolls during the late 1950s) was further transported eastward with the Kuroshio and North Pacific Currents within several years of deposition and was accumulated in the eastern North Pacific Ocean until 1967. Subsequently, ¹³⁷Cs concentrations in the eastern North Pacific Ocean decreased due to southward transport. Less radioactively contaminated seawater was also transported northward, upstream of the North Equatorial Current in the western North Pacific Ocean in the 1970s, indicating seawater re-circulation in the North Pacific Gyre.

Depositional behaviors of plutonium and thorium isotopes at Tsukuba and Mt. Haruna in Japan indicate the sources of atmospheric dust

Monthly plutonium and thorium depositions at Tsukuba (28m asl) and Mt. Haruna (1370m asl) were measured during 2006 and 2007 (Jan 2006-Dec 2007 at Tsukuba, Nov 2006-Dec 2007 at Mt. Haruna). The monthly (239,240)Pu depositions ranged from 0.044 to 2.67mBq m(-2) at Tsukuba and from 0.05 to 0.9mBq m(-2) at Mt. Haruna during the measurement periods. Monthly (239,240)Pu deposition did not differ markedly between the two sites except in April 2007. Seasonal pattern of monthly (239,240)Pu depositions at both sites showed high in spring and low in summer, and typical of seasonal variations in northeastern Asia. Thorium deposition at Tsukuba was higher than that at Mt. Haruna except in May and June 2007. (230)Th/(232)Th activity ratios were used to partition deposition samples into locally and remotely derived fractions. The results revealed that a major proportion of total (239,240)Pu and Th deposits are derived from remote sources, especially in spring.

Trans-Tenon's retrobulbar triamcinolone acetonide injection for macular oedema related to branch retinal vein occlusion

BACKGROUND

The aim of the study was to evaluate the safety and effectiveness of trans-Tenon's retrobulbar triamcinolone acetonide (TA) injection for macular oedema associated with branch retinal vein occlusion (BRVO).

METHODS

We reviewed the medical records of 50 consecutive patients with macular oedema associated with BRVO who were treated with trans-Tenon's retrobulbar TA injection (20 mg) as initial treatment for a follow-up period of at least 12 months. Foveal thickness determined by optical coherence tomography, visual acuity, intraocular pressure (IOP) and cataract progression were measured.

RESULTS

The mean duration between oedema onset and TA injection was 4.9 months. Foveal thickness decreased significantly at 3 months after injection (p<0.0001). Furthermore, the percentage reduction in foveal thickness in eyes with posterior vitreous detachment (PVD; n = 23) was significantly greater than that without PVD (n = 27, p = 0.003). Improved visual acuity by at least 0.20 log minimum angle of resolution (logMAR) was seen in 22 eyes (44%; 11 eyes with PVD and 11 eyes without PVD). After completion of the 3-month follow-up, 29 eyes (58%) needed additional treatment including TA injections or pars plana vitrectomy (PPV). PPV seemed to be effective for macular oedema resistant to TA. IOP elevation and cataract progression occurred in less than 10% of all patients.

CONCLUSIONS

Trans-Tenon's retrobulbar TA injection appeared safe and relatively effective for macular oedema associated with BRVO. In eyes resistant to TA injection, PPV may be effective as an adjunctive treatment.

The prevalence of Helicobacter pylori infection and the status of gastric acid secretion in patients with gastroesophageal junction adenocarcinoma in Japan

We have previously reported that H. pylori infection prevents reflux esophagitis (RE) and Barrett's esophagus (BE) by decreasing gastric acid secretion. Gastroesophageal (GE) junction adenocarcinoma, including Barrett's adenocarcinoma, has been thought to be a complication of gastroesophageal reflux disease. However, the relationship between H. pylori infection, gastric acid secretion and GE junction adenocarcinoma had not yet been investigated in Japan. We demonstrated that the status of gastric acid secretion was higher in patients with GE junction adenocarcinoma than in patients with early gastric cancer (EGC), and that the level was the same in patients with RE and those with BE. We also found that the prevalence of H. pylori infection in patients with GE junction adenocarcinoma was significantly lower than that in patients with EGC, although not as low as that in patients with RE and BE, suggesting that preservation of gastric acid secretion may be important for the development of GE junction adenocarcinoma in Japanese people, regardless of the presence of H. pylori infection.

Whole-liver graft without the retrohepatic inferior vena cava for sequential (domino) living donor liver transplantation

Grafts used in Domino liver transplantation (LT) obtained from living donor liver transplantation (LDLT) for familial amyloid polyneuropathy (FAP) patients have been mainly used as reduced grafts. Because of small-for-size problems seen in LDLT, using whole liver grafts could improve post-LT outcome. Eight consecutive Domino LDLT using whole livers without retrohepatic inferior vena cava (IVC) from FAP patients were retrospectively analyzed. The graft weight/recipient's body weight ratio (GWRW) in the domino recipients ranged from 1.28% to 2.4% (mean: 1.52). Multiple vascular reconstructions in the whole-liver domino LT resulted in longer than usual warm ischemia time (mean: 64 min); however immediate post-operative recovery of hepatic function was uneventful. At 8-40 months after the transplant, all the FAP patients are well and all of the domino recipients are alive. Domino LT using a whole FAP liver from a LDLT for a FAP patient presents satisfactory results, even though the transplant procedure is technically complicated.

Iatrogenic amyloid neuropathy in a Japanese patient after sequential liver transplantation

A 57-year-old woman in Japan, the first recipient of part of a liver from a 58-year-old man with familial amyloidotic polyneuropathy (FAP) amyloidogenic transthyretin Val30Met who had had sensorimotor polyneuropathy in the lower limbs for 3 years, started to develop sensory neuropathy 7 years after transplantation. Before the July 1998 sequential transplantation, she had been in a hepatic coma at the terminal stage of primary biliary cirrhosis and waiting for deceased donor liver transplantation. In September 2004, biopsy samples of her duodenum first showed amyloid deposition. Although biopsy materials in 2005 and 2006 showed no changes in amyloid deposition, decreased temperature sensation and pain in fingertips and toes were detected at a neurologic examination in March 2006. Thus, clinical symptoms of FAP appeared about 2 years after amyloid deposition started. Nerve conduction velocity studies revealed mild to moderate axonal sensory polyneuropathy without demyelination. Our findings confirmed iatrogenic sensory neuropathy induced by amyloid deposition 7 years after sequential liver transplantation.

Long-term outcome of adult-to-adult living donor liver transplantation for post-Kasai biliary atresia

Our objective was to analyze problems in the perioperative management and long-term outcome of living donor liver transplantation (LDLT) for biliary atresia (BA). Many reports have described the effectiveness of liver transplantation (LT) for BA, particularly in pediatric cases, but little information is available regarding LT in adults (> or =16 years old). Between June 1990 and December 2004, 464 patients with BA underwent LDLT at Kyoto University Hospital, of whom 47 (10.1%) were older than 16 years. In this study, we compared the outcomes between adult (> or =16 years old) and pediatric (<16 years old) patients. The incidence of post-transplant intestinal perforation, intra-abdominal bleeding necessitating repeat laparotomy and biliary leakage was significantly higher (p < 0.0001, <0.001 and <0.001, respectively) in adults. Overall cumulative 1-, 5- and 10-year survival rates in pediatric patients were significantly higher (p < 0.005) than in adults. Two independent prognostic determinants of survival were identified: a MELD score over 20 and post-transplant complications requiring repeat laparotomy. Outcome of LDLT in adult BA patients was poorer than in pediatric patients. It seems likely that LT will be the radical treatment of choice for BA and that LDLT should be considered proactively at the earliest possible stage.

Clinical characteristics and the prognosis of rhabdomyosarcoma - a report from the Study Group for Pediatric Solid Malignant Tumors in the Kyushu Area, Japan

AIM

There have been no nationwide group studies for patients with rhabdomyosarcoma in Japan. This study aims to assess the actual state of treatments and their outcome.

PATIENTS AND METHODS

From 1982 to 1996, 79 rhabdomyosarcomas were registered by the Study Group for Pediatric Solid Malignant Tumors in the Kyushu Area. The prognostic factors and treatments were assessed based on the 5-year survival rate. The staging was done according to the Intergroup Rhabdomyosarcoma Study (IRS) Clinical Grouping Classification.

RESULTS

The 5-year survival rate for all patients was 39.1 %. The survival rates for each factor were as follows, according to 1) group; 77.8 % for Group I, 51.9 % for Group II, 33.7 % for Group III, and 20.2 % for Group IV; 2) primary site: 56.3 % for the head and neck, 43.8 % for the parameningeal region, 12.5 % for the extremity, 58.3 % for the genitourinary region, and 30.5 % for the others; 3) histology: 35.8 % for the embryonal type, 36.8 % for the alveolar type.

CONCLUSIONS

Altogether, the outcome of this study was poor. To improve outcomes, a new nationwide group study for rhabdomyosarcoma, which we belong to, has just started in Japan.

Improved survival outcome for hepatoblastoma based on an optimal chemotherapeutic regimen--a report from the study group for pediatric solid malignant tumors in the Kyushu area

BACKGROUND/PURPOSE

The survival outcome for patients with hepatoblastoma normally depends on the resectability of the tumor. In Japan, the pre and/or postoperative chemotherapy protocol using a combination of cisplatin (CDDP) and tetrahydropyranyl-Adriamycin (THP-ADR) has been the standard treatment since 1991. This study aims to assess exactly what influence the establishment of this chemotherapy protocol has had on both the tumor resectability and the outcome of patients with hepatoblastoma.

METHODS

From 1982 to 1997, 60 patients with hepatoblatoma were treated in the Kyushu area, Japan. Based on the pretreatment extent of disease (PRETEXT), the outcome and tumor resectability were compared between group A (1982 to 1990, n = 27, PRETEXT I:5, II:8, III:6, IV:8) and group B (1991 to 1997, n = 33, PRETEXT I:9, II:9, III:5, IV:10).

RESULTS

The 5-year survival rates (group A and group B) were 33% and 73% for all cases (P <.01), 100% and 89% for PRETEXT I, 38% and 89% for II (P <.05), 17% and 80% for III (P <.01), and 0% and 40% for IV (P <.01), respectively. The 5-year survival rates for patients with metastases were 0% for group A (n = 5) and 57% for group B (n = 7; P <.01). The rates of a complete resection of primary tumor were 48% for group A and 67% for group B. In particular, a significant difference was found regarding the complete resection rate between groups A and B in the patients with PRETEXT III (17% for group A and 80% for group B; P <.01). In the patients with an incomplete tumor resection (14 for group A, 11 for group B), the 5-year survival rates were 0% for group A and 45% for group B (P <.01).

CONCLUSIONS

The optimal chemotherapeutic regimen of CDDP and THP-ADR was thus found to greatly contribute to the improved survival rate of hepatoblastoma patients. Preoperative chemotherapy resulted in an increased resectability of the tumor, whereas postoperative chemotherapy played an important role in the increased cure rate of cases with either an incomplete tumor resection or metastasis. However, refractory cases with PRETEXT IV or metastasis may still require the development of an even more effective treatment modality, including the use of blood stem cell transplantation.

Living donor liver transplantation: Eastern experiences

The techniques of living donor liver transplantation (LDLT) developed rapidly in the 1990s to compensate for a severe deficiency in the availability of liver grafts from cadaveric donors for the treatment of patients with end-stage liver disease. This tendency was particularly prominent in East Asia, as brain-death donors have remained largely unavailable for a variety of reasons. Thanks to refinements in surgical technique and postoperative management for LDLT, the cumulative total of LDLTs in East Asian countries has exceeded 2000 and, importantly, donor mortality has yet to be encountered. Moreover, indications for LDLT have been successfully expanded from paediatric to adult cases, following the introduction of right lobe graft. The significance of LDLT under conditions of limited opportunities for cadaveric liver transplantation, as experienced in these countries, differs significantly from that seen with the numerous opportunities for cadaveric donors in Europe and the USA. This review describes not only the experiences of East Asia, but also the specific differences from Western countries, such as indications, graft size issues and ABO blood type combinations, to shed light on the future of liver transplantation.

Malignant germ cell tumors: clinical characteristics, treatment, and outcome. A report from the study group for Pediatric Solid Malignant Tumors in the Kyushu Area, Japan

PURPOSE

This study aims to assess the prognostic factors and optimal treatments for malignant germ cell tumors (MGCT) in childhood.

METHODS

Among 117 MGCT, the clinical features were analyzed. Regarding the histology, there were 89 embryonal carcinomas, 13 dysgerminomas, 4 choriocarcinomas, and 11 others. The prognostic factors and treatments were assessed based on the 5-year survival rate.

RESULTS

(1) Stage: 100% for stage I (n = 54), 75.0% for stage II (n = 4), 67.3% for stage III (n = 14), and 54.8% for stage IV (n = 33); Unknown: n = 12. (2) Primary site: 93.4% for the testis (n = 52), 86.7% for the ovary (n = 31), 56.9% for the sacrococcygeal (n = 21), and 60.6% for others (n = 12); unknown: n = 1. (3) Surgical intervention for primary tumor: 100% for stage I with a complete resection (n = 53), 78.4% for stage III, IV with a complete resection (n = 26), and 33.3% for stage III, IV with an incomplete resection (n = 21). (4) Type of chemotherapy for the stage III and IV: 83.9% for the PVB (cisplatin, vinblastin, bleomycin; n = 13), 66.7% for the VAC (vincristine, actinomycin D, cyclophosphamide; n = 6), and 47.1% for other regimens (n = 25).

CONCLUSIONS

An early stage, a diagnosis under 1 year of age and a primary site in the gonads were favorable prognosis factors, whereas histologic findings of choriocarcinoma and liver or lung metastasis were unfavorable. Radical complete resection alone is a sufficient treatment for localized MGCT. The PVB regimen is optimal chemotherapy for advanced MGCT; however, high-risk cases still may require more aggressive treatment.

The efficacy of prevascularization by basic FGF for hepatocyte transplantation using polymer devices in rats

This study used polymer devices implanted in rats to investigate the effect of prevascularization by basic fibroblast growth factor (bFGF) on hepatocyte transplantation (HTx). Lewis rats served as both donors and recipients. Polyvinyl alcohol (PVA) sponges with either hydrogel containing bFGF (bFGF group) or distilled water (control group) were implanted between the mesenteric leaves of recipient rats. Hepatotrophic stimulation was induced by a portacaval shunt and a 70% partial hepatectomy. After 1 week of prevascularization, hepatocytes harvested from the donor Lewis rats using a collagenase digestive method were injected into the sponges. Specimens were harvested at 2 weeks, 1 month, and 2 months after HTx. Histologic examination revealed that the control groups contained small numbers of hepatocytes restricted to the peripheral areas of the sponges. However, a large number of hepatocytes, including clusters, was found distributed uniformly in the bFGF group. In the bFGF group at 2 weeks, 1 month, and 2 months, the percentage of the sponge occupied by hepatocytes was 7.21+/-2.64%, 6.98+/-2.59%, and 5.58+/-3.77%, respectively. The corresponding ratios for the control group were 0.40+/-0.39%, 0.40+/-0.40%, and 0.87+/-1.51%. In addition, the mean number of new blood vessels in the bFGF group was significantly greater than that in the control group at 0 days, 2 weeks, and 1 month after HTx. These results suggest that bFGF strongly induced vascularization, which enabled a large number of hepatocytes to survive in the polymer devices.

Pathogenesis and treatment of bile duct loss after liver transplantation

The bile duct is one of the main targets of immune reaction after liver transplantation. Bile duct loss, termed ductopenia or vanishing bile duct syndrome, is a typical pathological finding of chronic rejection (CR). The mechanism of bile duct loss in allograft rejection is twofold: T-cell mediated cytotoxicity and ischemic sequelae caused by obliterative arteriopathy. Whether or not CR is reversible remains controversial. Accumulating data show the reversibility of bile duct injury caused by immunoreaction, but not the reversibility of injuries caused by ischemia. In our living-related liver transplantation program at Kyoto University Hospital, the incidence of ductopenia, which indicates the incidence of CR, was 14 of 423 patients (3.3%), comparable to the result for cadaveric liver transplantation. The onset was within 1 year, except in 2 patients. Of the 14 patients with ductopenia, 2 recovered without re-transplantation, and of the remaining 12 patients, 7 underwent re-transplantation, and the other 5 died without a chance of re-transplantation. The diagnosis of ductopenia was based on the pathological findings, which specify that more than 50% of the portal triad does not contain visible bile ducts. Recently, staging criteria of CR were proposed by an international panel, who recommended splitting CR into an early stage and a late stage. At present, no specific immunosuppressive regimen for CR has been developed; however, early diagnosis based on these new criteria, and the earlier implementation of enforced immunosuppression, with conventional drugs, may be beneficial for a further reduction in CR.

Determination of hydrogen peroxide by iron(III) complex of thiacalix[4]arenetetrasulfonate on a modified ion-exchanger with peroxidase-like catalytic activity

An iron(III) complex of thiacalix[4]arenetetrasulfonate on a modified anion-exchanger (Fe3+-TCAS(A-500)) has shown high peroxidase-like activity at pH 5 - 6 for the reaction of quinoid-dye formation between 3-methyl-2-benzothiazolinone hydrazone and N-(3-sulfopropyl)aniline in the presence of hydrogen peroxide. Utilizing the peroxidase-like activity of Fe3+-TCAS(A-500) for this reaction, a method using Fe3+-TCAS(A-500) was applied for the spectrophotometric determination of hydrogen peroxide. The calibration curve by the method using Fe3+-TCAS(A-500) was linear over the range from 1 to 10 microg of hydrogen peroxide in a 1 ml sample solution. The apparent molar absorptivity for hydrogen peroxide was 2.4 x 10(4) l mol(-1) cm(-1). which was about 80% of that by peroxidase under the same conditions. This determination method of hydrogen peroxide using Fe3+-TCAS(A-500) was applied for the determination of glucose in diluted normal and abnormal control serum I and II.

Living-donor liver transplantation for Caroli's disease with intrahepatic adenocarcinoma

A 36-year-old woman who had Caroli's disease with refractory cholangitis and complicated intrahepatic cholangiocarcinoma was successfully treated with living-donor liver transplantation. Preoperative computed tomography and ultrasonography showed a small nodule in the dilated intrahepatic bile duct. In the resected liver specimen, a small papillary tumor was located in the dilated intrahepatic bile duct of the right lobe. The pathological finding revealed a well differentiated papillary adenocarcinoma without invasion to the parenchyma. The patient is currently doing well 2.5 years after transplantation, with no signs of recurrence of the disease. For Caroli's disease, we believe we can achieve good results with liver transplantation, not only for cholangitis but also for the carcinoma when it is localized in the liver and the patient is carefully followed up.

Biliary anastomotic complications in 400 living related liver transplantations

The purpose of this study was to evaluate the cause and outcome of biliary anastomotic complications occurring after living related liver transplantation (LRLT). A database of 391 patients undergoing 400 LRLT from June 1990 to August 1998 was reviewed. The overall incidence of biliary anastomotic complications was 18.2% (71 patients). There were 45 bile leaks, 35 anastomotic strictures, and the bile duct was ligated inadvertently in 3 cases. Univariative analysis revealed that the manner of stent usage, intrapulmonary shunting, and gender of recipients were significant risk factors for leakage. Anastomotic leaks, cytomegalovirus infection, hepatic artery complications, and gender of recipients were significant risk factors for stricture. In pediatric patients older than 2 years old, ABO blood type compatibility was another risk factor for leakage and stricture. Choice of stent usage and earlier transplantation for patients with intrapulmonary shunting should reduce the rate of biliary leaks, and prophylaxis of leaks for patients with intrapulmonary shunting, and minimizing hepatic artery complications should reduce the rate of biliary stricture after LRLT. Avoidance of ABO-incompatible donors or innovative immunosuppression in ABO-incompatible transplantation should be considered in children.

Clinical implications of flow cytometry crossmatch with T or B cells in living donor liver transplantation

BACKGROUND

Acute allograft rejection (AR) in solid organ transplantation is generally regarded to develop through cell-mediated immune response following activation of helper T cells. Since production of antibodies is also mediated by helper T cells, humoral immunity may play some roles in AR. Although flow cytometry crossmatch (FCXM) is reported as a useful method for the detection of antibodies against donor antigen, specific role of T- or B-cell FCXM and its sensitivity for AR is controversial.

METHODS

T- and B-cell FCXM using fresh donor peripheral lymphocytes were performed before and after blood-type compatible living donor liver transplantation in 47 patients. IgM and IgG anti-donor antibodies were analyzed in relation to clinical AR.

RESULTS

Positive pre-transplant T-cell FCXM was associated with a high incidence of positive post-transplant T-cell FCXM (p=0.017). Four of five cases (80%) with positive pre-transplant T-cell FCXM experienced earlier AR (day 8.0+/-4.4, mean+/-SD) than 16 of 42 cases (31%) with negative pre-transplant T-cell FCXM (17.3+/-6.8; p=0.016). In addition, higher dose of steroids was given to treat AR episodes in cases with positive pre-transplant T-cell FCXM (79.9+/-10.3 mg/kg/month) than in those with negative pre-transplant T-cell FCXM (47.1+/-26.6; p=0.039). In the first month after transplantation, 13 episodes of positive post-transplant T-cell FCXM were all concomitant with or preceded clinical AR compared with seven ARs in T-cell FCXM-negative cases (p<0.0001). T-cell FCXM between positive sera and third parties revealed some crossreactions. In contrast, detection of antibodies by B-cell FCXM in pre- and post-transplant phases was scarcely associated with AR, and no correlation was found between T- and B-cell FCXM before and after transplantation.

CONCLUSIONS

Positive T-cell FCXM is closely related with AR and that before transplantation is a predictor of early and refractory AR as well as post-transplant FCXM. In contrast, not a few detections of antibodies irrelevant to AR are observed in B-cell FCXM, suggesting its low specificity.

Weaning of immunosuppression in living donor liver transplant recipients

BACKGROUND

Some reported studies have indicated the possibility of immunosuppression withdrawal in cadaveric liver transplantation. The aim of this study was to evaluate the possibility and feasibility of weaning living donor liver transplant recipients from immunosuppression.

METHODS

From June of 1990 to October of 1999, 63 patients were considered to be weaned from immunosuppression. They consisted of 26 electively weaned patients and 37 either forcibly or incidentally weaned patients (nonelective weaning) due to various causes but mainly due to infection. Regarding elective weaning, we gradually reduced the frequency of tacrolimus administration for patients who survived more than 2 years after transplantation, maintained a good graft function, and had no rejection episodes in the preceding 12 months. The frequency of administration was reduced from the conventional b.i.d. until the start of weaning to q.d., 4 times a week, 3 times a week, twice a week, once a week, twice a month, once a month, and finally, the patients were completely weaned off with each weaning period lasting from 3 to 6 months. The reduction method of nonelective weaning depended on the clinical course of each individual case. When the patients were clinically diagnosed to develop rejection during weaning, then such patients were treated by a reintroduction of tacrolimus or an additional steroid bolus when indicated.

RESULTS

Twenty-four patients (38.1%) achieved a complete withdrawal of tacrolimus with a median drug-free period of 23.5 months (range, 3-69 months). Twenty-three patients (36.5%) are still being weaned at various stages. Sixteen patients (25.4%) encountered rejection while weaning at median period of 9.5 months (range, 1-63 months) from the start of weaning. All 16 were easily treated with the reintroduction of tacrolimus or additional steroid bolus therapy.

CONCLUSIONS

We were able to achieve a complete withdrawal of immunosuppression in some selected patients. Although the mechanism of graft acceptance in these patients has yet to be elucidated, we believe that a majority of long-term patients undergoing living donor liver transplantation may, thus, be potential candidates to be successfully weaned from immunosuppression.

Microcirculatory changes in right lobe grafts in living-donor liver transplantation: a near-infrared spectrometry study

BACKGROUND

A continuing shortage of cadaveric liver even for adult patients has motivated not a few centers to proceed to living-donor liver transplantation using right lobe grafts. One of controversies is potential congestion in the graft anterior segment by the deprivation of the middle hepatic vein.

METHODS

Hepatic tissue oxygenation and hemoglobin concentration were investigated with a near-infrared spectroscopy in the course of harvesting and implantation in living-donor liver transplantation. Twenty adult recipients of right lobe graft were involved in the study. The aim of the analysis was to detect tissue congestion or ischemia.

RESULTS

No significant change in mean hepatic tissue oxygenation and hemoglobin was noted in the right lobe during donor operation even after hepatic parenchymal transection, although some trend for relative congestion, i.e., increased tissue hemoglobin, compared with the left lobe was observed. After graft reperfusion in the recipient, both mean hepatic tissue oxygen saturation and hemoglobin decreased significantly in the anterior segment, which was accompanied by increased heterogeneity of tissue hemoglobin and oxygenation. Increased heterogeneity of oxygenation and decreased tissue hemoglobin were observed also in the posterior segment.

CONCLUSIONS

The anterior segment in right lobe living-donor liver transplantation is sensitive to ischemia, rather than congestion, at least in the immediate phase after graft reperfusion. The anterior segment seems to be also more prone to circulatory disturbance than the other part of the graft.

Variant transthyretin in blood circulation can transverse the blood-cerebrospinal barrier: qualitative analyses of transthyretin metabolism in sequential liver transplantation

BACKGROUND

Although the choroid6 plexus of the brain is one of the most important production sites of transthyretin (TTR), the metabolism of TTR secreted in cerebrospinal fluid (CSF) remains to be elucidated.

METHODS

To perform qualitative analysis of variant TTR in CSF of patients who underwent a sequential liver transplantation using an explanted familial amyloidotic polyneuropathy (FAP) ATTR Val30 Met patient's liver, levels and forms of TTR of the two patients were analyzed by means of enzyme linked immunosorbent assay (ELISA) and matrix-assisted laser desorption/time-of-flight mass spectrometer (MALDI/TOF-MS), respectively.

RESULTS

After the operation, variant TTR levels in serum increased, and in CSF, a significant peak of free form of ATTR Val30 Met was detected in the transplanted patients whose CSF had shown no variant TTR before the operation.

CONCLUSIONS

These findings suggest that the variant TTR can cross-the blood-CSF barrier and migrate into CSF from blood circulation. Because leptomeningeal amyloidosis occurs in FAP ATTR Val30 Met as the progression of the disease, this information suggests that in addition to peripheral neuropathy, disorders of the central nervous system (CNS) should be given an attention in patients who underwent sequential liver transplantation using an explanted FAP ATTR Val30 Met patient's liver.

The DSL domain in mutant JAG1 ligand is essential for the severity of the liver defect in Alagille syndrome

Alagille syndrome (AGS) is a congenital multi-system anomaly mainly characterized by paucity of intrahepatic bile ducts caused by haploinsufficiency of the Jagged 1 gene (JAG1). To explore the relationship between genotype and phenotype, we analyzed the JAG1 gene in 25 Japanese AGS families at the genomic DNA level and identified 15 point mutations and one large deletion. Analysis of the genotype and phenotype strongly indicated that the Delta/Serrate/Lag-2 (DSL) domain in JAG1 protein played an essential role in determining the severity of the liver disorder. In four sporadic cases, missing an entire DSL domain in mutant JAG1 resulted in progressive liver failure and all 4 patients needed a liver transplant at a very young age. This correlation was further confirmed by statistical analysis (chi2=9.143, p<0.001). Our finding demonstrated that the DSL domain in JAG1 appears to be essential for normal liver development and function.