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H Matsunami

Publications and source records attributed to H Matsunami.

At least 37 records · Page 2Linked to original sources
PubMed1997

Peripheral nerves regenerated in familial amyloid polyneuropathy after liver transplantation.

BACKGROUND: Liver transplantation holds promise as a treatment for familial amyloid polyneuropathy. OBJECTIVE: To determine whether peripheral nerves regenerate in patients with familial amyloid polyneuropathy after liver transplantation. DESIGN: Case report. SETTING: University hospital in Matsumoto, Japan. PATIENT: A 34 year-old-women with familial amyloid polyneuropathy who had liver transplantation and showed marked clinical improvement 3 years after surgery. MEASUREMENTS: Histopathologic examination and morphometric analysis of biopsy specimens taken from sural nerves. RESULTS: Diffuse fiber loss and amyloid deposits were seen in a biopsy specimen of the left sural nerve obtained before liver transplantation (total number of myelinated fibers, 1326/mm2 of the endoneurial area). In the biopsy specimen of the right sural nerve, which was obtained 3 years after transplantation, amyloid deposits remained but the number of myelinated fibers was markedly increased (total number of myelinated fibers, 4740/mm2). CONCLUSION: Peripheral nerves regenerated in a patient with familial amyloid polyneuropathy after liver transplantation.

Adult↗
PubMed1997

A multigene family encoding a diverse array of putative pheromone receptors in mammals.

The vomeronasal organ of mammals is an olfactory sensory structure that detects pheromones. It contains two subsets of sensory neurons that differentially express G alpha(o) and G alpha(i2). By comparing gene expression in single neurons, we identified a novel multigene family that codes for a diverse array of candidate pheromone receptors (VRs) expressed by the G alpha(o)+ subset. Different VRs are expressed by different neurons, but those neurons are interspersed, suggesting a distributed mode of sensory coding. Chromosome mapping experiments suggest an evolutionary connection between genes encoding VRs and receptors for volatile odorants. However, a dramatically different structure for VRs and the existence of variant VR mRNA forms indicate that there are diverse strategies to detect functionally distinct sensory stimuli.

Amino Acid Sequence↗
PubMed1997

Efficacy of quantitative analysis of Epstein-Barr virus-infected peripheral blood lymphocytes by in situ hybridization of EBER1 after living-related liver transplantation: a case report.

BACKGROUND: We describe a 1-year-old female who underwent living-related liver transplantation for biliary atresia and developed Epstein-Barr virus (EBV)-related posttransplant lymphoproliferative disorder. This disorder was resolved after withdrawal of immunosuppression therapy and administration of a high dose of acyclovir. METHODS: To quantify the extent of EBV activation and EBV load in peripheral blood, we measured the levels of EBV-infected peripheral lymphocytes by in situ hybridization (ISH) of EBV-encoded small mRNA 1 (EBER1). RESULTS: The decline in the number of EBER1-positive lymphocytes (from 362/50,000 mononuclear cells to 0/50,000) after treatment was in accord with the patient's clinical improvement. CONCLUSIONS: This finding showed that quantitative analysis of EBV-infected peripheral lymphocytes by ISH of EBER1 is very useful for monitoring the EBV load and response to treatment of patients with EBV-related disorders. Furthermore, ISH may become an important tool for the early diagnosis and prevention of life-threatening posttransplant lymphoproliferative disorder in posttransplant patients.

Acyclovir↗
PubMed1997

Cadherin-6 expression transiently delineates specific rhombomeres, other neural tube subdivisions, and neural crest subpopulations in mouse embryos.

Mammalian cadherin-6 (K-cadherin, cad6) was originally identified by means of the polymerase chain reaction, but its biological functions have not yet been determined. We analyzed the expression pattern of the mouse homologue of this cadherin during development and found that it was transiently expressed in restricted rhombomeres and in other subdivisions of the neural plate and tube. In the midbrain and anterior hindbrain of E8.0-8.5 embryos, cad6 was expressed only in neural crest-generating regions. In contrast, in the posterior hindbrain and contiguous spinal cord of these embryos, cad6 occurred throughout the neural plate, forming a sharp anterior limit at the future rhombomere 4 and 5 boundary. Subsequently, this neural plate expression became confined to rhombomere 6, although most of the neural crest-generating areas remained positive throughout the body. Neural crest cells expressing cad6 migrated out of the neural tube, and subsequently accumulated mainly along peripheral nerves. We then studied the effect of Hoxa-1 mutation on the expression of cad6, as their expressions spatiotemporally overlapped with each other in the early posterior hindbrain. In E8.0-8.5 Hoxa-1 mutants, cad6 expression was suppressed in the region of rhombomeres 4 to 6, although that in the other regions was not essentially affected. At later stages, however, cad6-positive crest cells appeared and migrated out of rhombomeres 4 to 6, indicating that the suppression of cad6 expression was transient and restricted to early stages. Importantly, this effect of the Hoxa-1 mutation concurred with the timing of the expression of this gene. We also studied Hoxa-3 mutants, but found no effect of this mutation on the cad6 expression pattern. These findings suggest that cad6 may contribute to the formation of the segmental structure of the early brain through its ability to confer specific adhesiveness on cells and that Hoxa-1 may be required for early cad6 expression in the posterior hindbrain.

Amino Acid Sequence↗
PubMed1997

Developmental defects in mouse embryos lacking N-cadherin.

To investigate the functions of N-cadherin in vivo, we have mutated the gene encoding this adhesion protein in mice. Although N-cadherin is expressed at the time of gastrulation and neurulation, both neurulation and somitogenesis initiate apparently normally in homozygous mutant embryos. However, the resulting structures are often malformed. The somites of the mutant embryos are small, irregularly shaped, and less cohesive compared with those of their wild-type littermates, and the epithelial organization of the somites is partially disrupted. Undulation of the neural tube is also observed in the mutant embryos. Homozygous mutant embryos die by Day 10 of gestation. The mesodermal and endodermal cell layers of the yolk sac are separated in the mutants. The most dramatic cell adhesion defect is observed in the primitive heart; although myocardial tissue forms initially, the myocytes subsequently dissociate and the heart tube fails to develop normally. In vitro studies of cardiac myocytes derived from N-cadherin mutant embryos show that the cells can loosely aggregate and beat synchronously, demonstrating that electrical coupling can occur between N-cadherin-deficient cardiac myocytes. These results show that N-cadherin plays a critical role in early heart development as well as in other morphogenetic processes.

Animals↗
PubMed1997

Hepatic artery reconstruction in living donor liver transplantation from the microsurgeon's point of view.

Microvascular surgery for the reconstruction of the hepatic artery in living donor liver transplantation is discussed from the microsurgeon's point of view. A refined operative procedure to improve the safety of the anastomosis is described. In living donor liver transplantation, the hepatic artery of the graft is short and small, the operative site is deep and mobile, and the anatomic arrangement of the graft left hepatic artery may differ from that of the recipient's dilated hepatic artery. To create a safe anastomosis under these conditions, recipient arteries that were slightly smaller than the graft artery were dissected. Without the size discrepancy, and end-to-end anastomosis could be created. Some refinements to create a good operative field made the anastomosis easy. The apparatus and techniques used in free-flap transfer facilitated a clean anastomosis. We anastomosed 44 arteries in 40 patients undergoing living donor liver transplantation using microsurgical techniques. Neither a decrease in the arterial blood flow nor hepatic artery thrombosis was noted. The refined operative procedure we describe in this report can be used to overcome the problems associated with the hepatic artery anastomosis in living donor liver transplantation.

Adolescent↗
PubMed1997

Orthotopic liver transplantation for adult-onset type II citrullinaemia.

Citrullinaemia is a rare autosomal recessive disorder due to a deficiency of argininosuccinate synthetase (ASS). While the clinical course of the adult onset form (Type II) is unpredictable, many patients undergo sudden deterioration with progressive cerebral oedema. Two patients with Type II citrullinaemia were referred for liver transplantation. One patient was successfully transplanted, and his plasma citrulline level decreased from 300 to 69 mumol/l (normal range 20-60 mumol/l); Fisher's ratio increased to a normal range within 24 h of transplantation. The other patient died from cerebral oedema, despite Optimal pharmacological measures, while awaiting a suitable donor organ. Dietary and pharmacological treatment is vital before liver transplantation. The level of serum arginine requires regulation, as it can rise secondary to citrullinaemia in Type II disease. An immunocytochemical study of the liver in both patients showed a clustered distribution of ASS which is associated with a dismal prognosis compared with patients who have a homogenous distribution. Distribution of ASS was normal in the transplanted liver. Liver transplantation is effective therapy for adult-onset Type II citrullinaemia. A clustered pattern of ASS distribution in a liver biopsy is a significant feature to activate early referral for liver transplantation.

Adult↗
PubMed1996

Complete neurological recovery of an adult patient with type II citrullinemia after living related partial liver transplantation.

Type II citrullinemia is an adult-onset hepatocerebral disease caused by a deficiency of argininosuccinate synthetase in liver. A 25-year-old Japanese man suddenly developed encephalopathy, showing disorientation and flapping tremor. Plasma concentrations of ammonia and citrulline were extremely high, and hepatic argininosuccinate synthetase activity was deficient. The patient's condition deteriorated rapidly in spite of intensive medications. Therefore, we performed a partial liver transplantation using a graft obtained from his healthy 61-year-old father. After surgery, his neurological symptoms soon disappeared and plasma levels of ammonia and citrulline were normalized within 3 months after operation. Type II citrullinemia is one fulminant form of various liver-based metabolic diseases, and immediate liver transplantation is necessary to rescue patients with this disease. As liver transplantation from cadaveric donor is still not possible in Japan, it seems justifiable to use living related partial liver transplantation for our patient.

Adult↗
PubMed1996

Expression of cadherin-11 delineates boundaries, neuromeres, and nuclei in the developing mouse brain.

Cadherin-11 (cad11 or OB-cadherin) was previously identified as a mesenchymal cell-cell adhesion molecule. Here we studied the expression of cad11 transcripts in developing brains derived from E11.5 to E16.5 mouse embryos. In the brains at these stages, cad11 was expressed in various patterns, which could be grouped into three categories. First, cad11 expression occurred along boundaries between certain brain subdivisions, including those between the ventral and dorsal thalamus and between the mesencephalon and metencephalon. At these boundaries, cad11-positive cells were localized in a narrow, columnar compartment of the neuroepithelium. Second, cad11 expression delineated particular neuromeric compartments at the ventricular zone of the neuroepithelium. A typical example of this pattern was observed in the hypothalamus. Third, cad11 was expressed in differentiating or differentiated brain nuclei. The former included the thalamus, epithalamus, and pretectum; the latter included the mammillary, red, trigeminal motor, facial motor, prepositus hypoglossal, and inferior olive nuclei, as well as the substantia nigra. Furthermore, developing nuclei and the superficial zone of the cerebellum expressed cad11, and the cortical plate of the developing cerebrum also did so. We compared the expression pattern of cad11 with that of R-cadherin in the diencephalon and found that each cadherin delineated a unique set of diencephalic subdivisions. These findings suggest that cad11-mediated specific cell-cell adhesion plays roles in segmentation or compartmentalization of the developing brain in various ways. We also discussed the possibility that cad11 might be involved in neuronal connections between specific nuclei.

Animals↗
PubMed1996

Extended lateral segmentectomy using intraoperative ultrasound to obtain a partial liver graft.

The important features of extended lateral segmentectomy to obtain a partial liver graft comprising the left lateral segment and the left half of the medial segment are described with special reference to anatomical variation of the hepatic venous system. Ramification patterns of the hepatic vein tributaries around the juncture of the major hepatic veins with the inferior vena cava are delineated before starting liver resection, using intraoperative ultrasound. The left medial vein draining the left part of the medial segment is recognized close to the confluence of the middle and left hepatic veins. This tributary flows into the left hepatic vein in the majority of cases, but sometimes into the middle hepatic vein. The liver transection line is established in order to obtain the graft, including the drainage area of the left medial vein. Intraoperative ultrasound is indispensable for identifying the left medial vein in extended lateral segmentectomy.

Adolescent↗
PubMed1996

Should all hepatic arterial branches be reconstructed in living-related liver transplantation?

BACKGROUND: Because graft arteries are smaller and shorter in living-related liver transplantation (LRLT) than in whole or reduced-size liver transplantation from cadavers, arterial reconstruction is thought to be one of the critical points for success. METHODS: Thirty LRLT patients were classified into two groups: those in whom all graft hepatic arteries were reconstructed (group A), and those whom only had some were reconstructed (group B). In group A 17 patients had a single hepatic artery and three had two hepatic arteries. In group B the thickest one of several arteries was reconstructed, but the others were ligated after pulsatile back-bleeding from their cut stumps had been confirmed. The clinical results were compared between the two groups. RESULTS: Neither arterial thrombosis nor liver dysfunction related to the arterial blood supply was observed during the postoperative course. One case of bile leakage and two cases of bile duct stenosis occurred in group A. No significant difference was noted in the postoperative values of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase between the two groups. Overall patient and graft survival was 90%. CONCLUSIONS: Although several hepatic arteries may supply the potential allograft in LRLT, it is not always necessary to reconstruct all of them.

Adolescent↗
PubMed1996

Budd-Chiari syndrome caused by hepatic vein thrombosis in a patient with myeloproliferative disorder.

We report a 24-year-old Japanese female hospitalized with jaundice and ascites. She exhibited hepatosplenomegaly, severe liver dysfunction, and slight polycythemia with an increase in serum levels of beta-thromboglobin and platelet factor 4. Bone marrow was hypercellular with an increase in progenitor cells. The aggregation response of platelets to ADP and to collagen was markedly increased. Venography revealed narrowed hepatic veins with "spider web' sign. Liver biopsy revealed hepatic congestion. Budd-Chiari syndrome was diagnosed, and was thought to be due to thrombosis related to myeloproliferative disorder. Liver transplant was successful in relieving symptoms.

Adenosine Diphosphate↗
PubMed1995

Prevention of hepatic artery thrombosis in pediatric liver transplantation.

Hepatic artery thrombosis after orthotopic liver transplantation is a serious complication, especially in children. We report our experience with intensive anticoagulant therapy during and after living-related liver transplantation in pediatric recipients. Twenty-four patients between 5 months and 15 years of age were studied. The mean diameter of the anastomosed hepatic arteries was 2.7 mm. The anticoagulant therapy consisted of low-molecular-weight heparin, antithrombin III concentrates, prostaglandin E1, fresh frozen plasma, and a protease inhibitor. The profiles of the coagulation and fibrinolytic systems were monitored by measuring several parameters, including plasma levels of thrombin-antithrombin III complex, antithrombin III, plasmin-alpha 2 plasmin inhibitor complex, fibrin degradation product D-dimer, tissue type-plasminogen activator, and plasminogen activator inhibitor-1. Acceleration of the coagulation system and delayed recovery of the fibrinolytic system were observed during the early postoperative days. The plasma level of antithrombin III activity was maintained within the normal range by the administration of antithrombin III concentrates. None of the recipients developed hepatic artery thrombosis. Children have been reported to be at a greater risk of developing hepatic artery thrombosis than adults due to the small diameters of their hepatic arteries and the postoperative hypercoagulable state. We believe that the intensive anticoagulation therapy described in this study, the main concept of which is the early correction of imbalance between the coagulant and anticoagulant systems, could become a model for the prevention of hepatic artery thrombosis in pediatric liver transplantation patients.

Adolescent↗