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31.
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine carcinomas. Received: 14 April 1999 / Accepted: 7 July 1999  相似文献   
32.
We performed molecular analysis of a germline interstitial deletion of chromosome 4 [del(4)(q21.22q23)], which had been observed in a male infant manifesting early-onset hepatoblastoma (HBL). The chromosomal anomaly in this child was associated with a unique congenital syndrome including HBL, atrial septal defect, ventricular septal defect, patent ductus arteriosus, mental retardation, and seizures. However, the patient did not exhibit a megalencephaly typical of 4q21-22 deletions. His HBL was associated with an increasing serum alpha-fetoprotein level and rapid growth. To define the chromosomal deletion at the molecular level in this child, we analyzed his lymphoblasts with fluorescence in situ hybridization, using as probes a panel of BAC/PAC genomic clones containing STS markers covering the 4q12-27 region. The analysis revealed that the affected chromosome had an 8-cM deletion within 4q21-q22, flanked by markers D4S2964 and D4S2966. This microdeletion overlaps with the commonly deleted region at 4q21-q22 that was recently defined in adult hepatocellular carcinomas.  相似文献   
33.
A 69-year-old man in whom idiopathic enlargement of the right atrium was revealed at autopsy is described. The patient had had cardiomegaly of at least 19 years' duration prior to his death, even though cardiac symptoms were absent. Cause of death was pancreatic carcinoma. Postmortem examination revealed marked and diffuse dilatation of the right atrium and moderate dilatation of the left atrium. Measurement of the cardiac chambers showed that the right and left atria were 7.6 and 4.7 times as large as those of normal hearts, respectively. The volume of either ventricle was about twice the normal value. Histologically, widespread cardiac muscular degeneration and necrosis, diffuse fibrosis, and focal lymphocytic infiltration were found in the right atrium and also, to a lesser degree, in the left atrium. Such pathologic changes were not found in either of the ventricles. The etiology of these muscular changes, which might have been related to atrial enlargement, was unclear. The present case was thought to be consistent with idiopathic enlargement of the right atrium, and a brief review of the literature is given.  相似文献   
34.
Carcinoma arising from Rokitansky–Aschoff sinus (RAS) is extremely rare; only eight cases have been reported in the literature. Herein is reported a case of minute adenocarcinoma arising in RAS. A 77‐year‐old Japanese man with gallbladder stones underwent cholecystectomy. A tiny submucosal tumor (1 cm × 1 cm) was incidentally recognized. Histologically, the submucosal tumor was located in the subserosa and, to a lesser extent, in the fibromuscular layer. It was adenocarcinoma. RAS were recognized within the tumor, and there was a gradual transition between RAS and the adenocarcinoma. Mucin histochemistry indicated neutral and acidic mucins in the cytoplasm and lumens of the adenocarcinoma cells. Immunohistochemistry showed that the adenocarcinoma cells were positive for cytokeratin, epithelial membrane antigen, carbohydrate antigen 19‐9, K‐i67 (labeling = 80%), MUC1, MUC5AC and MUC6. In contrast, the adenocarcinoma cells were negative for CEA, c‐erbB2, p53 protein, MUC2 and CD10. In summary, minute subserosal adenocarcinoma, which arose in RAS, was found incidentally; therefore careful examination of resected gallbladders is necessary.  相似文献   
35.
We aimed to determine whether three-dimensional (3D) cartilage could be engineered from umbilical cord blood (CB) cells and compare it with both engineered fetal cartilage and native tissue. Ovine mesenchymal progenitor cells were isolated from CB samples (n=4) harvested at 80-120 days of gestation by low-density fractionation, expanded, and seeded onto polyglycolic acid scaffolds. Constructs (n=28) were maintained in a rotating bioreactor with serum-free medium supplemented with transforming growth factor-beta1 for 4-12 weeks. Similar constructs seeded with fetal chondrocytes (n=13) were cultured in parallel for 8 weeks. All specimens were analyzed and compared with native fetal cartilage samples (n=10). Statistical analysis was by analysis of variance and Student's t-test (p<.01). At 12 weeks, CB constructs exhibited chondrogenic differentiation by both standard and matrix-specific staining. In the CB constructs, there was a significant time-dependent increase in extracellular matrix levels of glycosaminoglycans (GAGs) and type-II collagen (C-II) but not of elastin (EL). Fetal chondrocyte and CB constructs had similar GAG and C-II contents, but CB constructs had less EL. Compared with both hyaline and elastic native fetal cartilage, C-II and EL levels were, respectively, similar and lower in the CB constructs, which had correspondingly lower and similar GAG levels than native hyaline and elastic fetal cartilage. We conclude that CB mesenchymal progenitor cells can be successfully used for the engineering of 3D cartilaginous tissue in vitro, displaying select histological and functional properties of both native and engineered fetal cartilage. Cartilage engineered from CB may prove useful for the treatment of select congenital anomalies.  相似文献   
36.
37.
An MRL strain of mice bearing a Fas-deletion mutant gene, lpr, MRL/MpJ-lpr/lpr (MRL/lpr) develops collagen disease involving vasculitis, glomerulonephritis, arthritis and sialoadenitis, each of which has been studied as a model for polyarteritis, lupus nephritis, rheumatoid arthritis and Sjögren’s syndrome, respectively. Development of such lesions seems dependent on host genetic background since the congenic C3H/HeJ-lpr/lpr (C3H/lpr) mice rarely develop them. To identify the gene loci affecting each lesion, a genetic dissection of these complex pathological manifestations was carried out. First, histopathological features in MRL/lpr, C3H/lpr, (MRL/lpr × C3H/lpr) F1 intercross, and MRL/lpr × (MRL/lpr × C3H/lpr) F1 backcross mice were analyzed. Genomic DNA of the backcross mice were subjected to association studies by Chi-squared analysis for determining which polymorphic microsatellite locus occurs at higher frequency among affected compared to unaffected individuals for each lesion. As a result, gene loci recessively associated with each lesion were mapped on different chromosomal positions. We concluded that each of these lesions in MRL/lpr mice is under the control of a different set of genes, suggesting that the complex pathological manifestations of collagen disease result from polygenic inheritance.  相似文献   
38.
Summary Hepatolithiasis is a common disease in East Asia though very rare in the West. Four cases of hepatolithiasis in which calculi were incidentally found in the peripheral branches of the intrahepatic biliary tree at autopsy are described and compared with hepatolithiasis involving the major branches of the intrahepatic biliary tree. These four cases were all elderly, three patients were male and one female. The calculi were brown pigment stones in each case, as seen in the major branch type. The stone-containing ducts showed mild fibrosis and glandular proliferation with inflammatory changes in three cases; these changes were marked in the fourth case. The hepatic parenchyma around the stone-containing ducts was atrophic or collapsed in all four cases. The major branches of the intrahepatic biliary tree as well as the extrahepatic tree failed to show findings suggestive of bacterial infections or biliary anomalies. These data suggest that brown pigment stones develop primarily in the peripheral ducts in the liver. It remains uncertain whether the peripheral type eventually progresses to the major type or not.  相似文献   
39.
MRL/MpJ-lpr/lpr (MRL/lpr) mice spontaneously develop various forms of autoimmune disease in the same individuals, including glomerulonephritis, polyarteritis, arthritis and sialoadenitis. An MRL recombinant congenic strain of mice bearing the gld gene, MRLiMpTn-gld/gld (MRL/gld), also develops lesions similar to those in MRL/lpr mice. The lpr and gld genes are a Fas deletion mutant and a Fas ligand mutant, respectively. Thus, autoimmune disease in these mice seemed to be a single gene disease involving the complex pathological manifestations as pleiotropy. However, comparative studies with C3H/HeJ and C57BL/6J strains of mice bearing lpr or gld revealed that these lesions developed only in mice with an MRL background. Moreover, these lesions were genetically segregated among MRL/lpr x (MRL/lpr x C3H/lpr)F1 mice. This indicates that an MRL strain has particular gene(s) affecting the development of each lesion. Association studies of each lesion with polymorphic microsatellite markers using backcross mice revealed that gene loci responsible for each lesion exist at different chromosomal positions and have additive and hierarchical properties of polygenic inheritance for some of the lesions. We conclude that the complex pathological manifestations of autoimmune disease are under the control of different combinations of polygenes.  相似文献   
40.
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