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11.
Hepatoblastoma is the most common malignant liver tumor in children. Recently, liver transplantation has been indicated for unresectable hepatoblastoma. We retrospectively reviewed 14 children with a diagnosis of hepatoblastoma who had undergone living-donor liver transplantation (LDLT) at Kyoto University Hospital. During the period from June 1990 to December 2004, 607 children underwent LDLT. Of these interventions, 2.3% were performed for hepatoblastoma. Based on radiological findings, the pre-treatment extent of disease (PRETEXT) grouping was used for pre-treatment staging of the tumor. There were grade III in seven patients and grade IV in seven patients. Thirteen patients received chemotherapy, and seven underwent hepatectomy 11 times. Immunosuppressive treatment consisted of tacrolimus monotherapy in 11 patients. Actuarial 1- and 5-year graft and patient survival rates were 78.6% and 65.5%. The poor prognostic factors were macroscopic venous invasion and extrahepatic involvement with 1-year and 5-year survival rates of 33.0% and 0%. Pediatric patients without these factors showed an acceptable 5-year survival rate of 90.9%. LDLT provides a valuable alternative with excellent results in children with hepatoblastoma because it allows optimal timing of the liver transplantation, given the absence of delay between the completion of chemotherapy and planned liver transplantation.  相似文献   
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We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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The pathogenesis of hepatitis C virus (HCV)-associated insulin resistance remains unclear. Therefore, we investigated mechanisms for HCV-associated insulin resistance. Homeostasis model assessment for insulin resistance was increased in patients with HCV infection. An increase in fasting insulin levels was associated with the presence of serum HCV core, the severity of hepatic fibrosis and a decrease in expression of insulin receptor substrate (IRS) 1 and IRS2, central molecules of the insulin-signaling cascade, in patients with HCV infection. Down-regulation of IRS1 and IRS2 was also seen in HCV core-transgenic mice livers and HCV core-transfected human hepatoma cells. Carbobenzoxy-l-leucyl-l-leucyl-l-leucinal, a potent proteosomal proteolysis inhibitor, blocked down-regulation of IRS1 and IRS2 in HCV core-transfected hepatoma cells. In human hepatoma cells, HCV core up-regulated suppressor of cytokine signaling (SOCS) 3 and caused ubiquitination of IRS1 and IRS2. HCV core-induced down-regulation of IRS1 and IRS2 was not seen in SOCS3(-/-) mouse embryonic fibroblast cells. Furthermore, HCV core suppressed insulin-induced phosphorylation of p85 subunit of phosphatidylinositol 3-kinase and Akt, activation of 6-phosphofructo-2-kinase, and glucose uptake. In conclusion, HCV infection changes a subset of hepatic molecules regulating glucose metabolism. A possible mechanism is that HCV core-induced SOCS3 promotes proteosomal degradation of IRS1 and IRS2 through ubiquitination.  相似文献   
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To evaluate the clinical applicability of galectin-3 and CD44 variant 6 (CD44v6) immunostaining in fine-needle aspiration cytology (FNAC) of thyroid follicular tumors, 79 cytological specimens (35 follicular carcinomas and 44 follicular adenomas) were studied. The positive rates of galectin-3 and CD44v6 were 89 and 74% in follicular carcinoma, respectively, and 25 and 30% in follicular adenoma, respectively. There were no significant correlations between the expression of galectin-3 or CD44v6 in follicular carcinoma and characteristics such as capsular invasion, vascular invasion, metastasis, or tumor size. Positive staining of either galectin-3 or CD44v6 resulted in a diagnostic sensitivity of 97% and a specificity of 52% for follicular carcinoma among follicular tumors. Immunostaining of galectin-3 or CD44v6 using cytological specimens can provide independent information on conventional morphological findings of cytology to distinguish follicular carcinoma from adenoma.  相似文献   
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A case of nonfunctioning parathyroid carcinoma in a 69-year-old female has been studied by light and electron microscopy. The tumor, located on the left side of the anterior neck, was well encapsulated by connective tissue but showed invasion to the capsule and to the thyroid. The tumor cells exhibited a trabecular arrangement surrounded by capillary networks but focally showed several ductal structures. They were polygonal in shape, had a large nucleus showing frequent mitosis and poor cytoplasm containing glycogen. Some tumor cells had clear and abundant cytoplasm, and resembled water-clear cells of the parathyroid. Immunohistochemically, no thyroglobulin was demonstrated in the tumor tissue. Electronmicroscopically, the tumor cells with high N/C ratio contained poorly developed cell organelles and abundant glycogen particles. They were poor in secretory granules and had no conglomeration of lipid. Desmosomes and tonoflbrils were observed. The ratio of the reported number of nonfunctioning parathyroid carcinoma to that of functioning one in Japan was compared with that in western countries. No difference of the ratio was found between these two, when identical criteria were employed.  相似文献   
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The expression of activin A, one of the transforming growth factor-beta supergene family, was studied in various pulmonary conditions associated with interstitial pulmonary fibrosis (3 cases with diffuse alveolar damage, 6 cases with idiopathic pulmonary fibrosis, and 1 case with pulmonary fibrosis associated with rheumatoid arthritis) using immunohistochemical techniques on paraffin-embedded sections. Controls consisted of 10 cases with normal pulmonary parenchyma, and 2 cases with primary pulmonary hypertension and 1 case with secondary pulmonary hypertension were also studied. The lung specimens from normal parenchyma weakly expressed immunoreactive activin A on the bronchiolar epithelium. In marked contrast, all of the specimens from cases with diffuse alveolar damage and interstitial pulmonary fibrosis demonstrated strong expression of activin A on metaplastic epithelium, hyperplastic smooth muscle cells, desquamated cells, and alveolar macrophages. Pulmonary arteries from patients with primary or secondary pulmonary hypertension showed abundant immunoreactive activin A on smooth muscle cells. These findings suggest a potential role for this growth factor, activin A, in the pathogenesis of pulmonary tissue remodeling associated with interstitial pulmonary fibrosis.  相似文献   
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Primary sclerosing cholangitis (PSC) is known to be frequently associated with inflammatory bowel diseases. In a rat with self-filling blind loop (SFBL), a proposed animal model for PSC, hepatobiliary inflammation has previously been demonstrated. In this study, we assessed the involvement of lipopolysaccharide (LPS), a bacterial endotoxin, in the pathogenesis of hepatobiliary inflammation of the SFBL model. The hepatic localization of LPS was examined by immunohistochemistry using an anti-lipid A antibody. The portal blood concentration of LPS was measured by an endotoxin-specific chromogenic Limulus test (Endospecy test). LPS was localized in the biliary epithelial cells (BECs) of rats with SFBL, and the portal blood concentration of LPS was significantly higher than that of sham-operated rats. Development of hepatobiliary inflammation, peribiliary fibrosis, and injury to the intestinal mucosa were histologically confirmed. Constriction in the biliary trees was radiologically demonstrated. These findings suggested that abnormal accumulation of LPS, which may be derived from portal blood, in BECs was involved in the pathogenesis of hepatobiliary inflammation with intestinal injury.  相似文献   
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