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11.
Abstract: A 63-year-old man was hospitalized because of jaundice and anorexia. An upper gastrointestinal series and hypotonic duodenography revealed circumferential sclerosis and stenosis of the duodenal wall. Endoscopic examination disclosed an ulcer, the upper margin of which was located at the papilla of Vater. The papilla was situated in the base of the ulcer. Endoscopic retrograde cholangiopancreatography disclosed mild dilatation of the common bile, intrahepatic bile and pancreatic ducts, but with neither severe stenosis nor occlusion. Nevertheless, there was some degree of circumferential compression and mild stenosis of the terminal portions of the bile and pancreatic ducts, as potential causes of obstructive jaundice in this patient. Computed tomographic examination of the abdomen revealed a tumorous lesion at the duodenal bulb. Because malignancy in the duodenum could not be ruled out, a pancreatoduodenectomy was performed. Histopathological examination showed a postbulbar duodenal ulcer, associated with inflammation of the papillary orifice and fibrosis of the region near the papilla. There was no evidence of a tumorous lesion. In this case, a postbulbar duodenal ulcer may have caused obstructive jaundice.  相似文献   
12.
Mixed dysembryoplastic neuroepithelial tumor and ganglioglioma   总被引:3,自引:0,他引:3  
We report a case of a 15-year-old girl with new onset seizures, who had a mixed dysembryoplastic neuroepithelial tumor (DNT) and ganglioglioma of the right parieto-occipital lobe. The tumor appeared well demarcated and exhibited a low T1 and a high T2 signal on magnetic resonance imaging. Architecturally it was in large part intracortical and multinodular, but also featured a leptomeningeal component. The former corresponded to DNT, a proliferation of oligodendroglia-like cells (OLCs) arranged in nodules, as well as comprising a diffuse internodular element featuring “floating neurons” in a mucoid matrix. The leptomeningeal portion of the lesion was a ganglioglioma consisting of large neurons and astrocytes in association with marked desmoplasia. Spacially, the two components abutted one another but appeared distinct. Immunohistochemistry showed the neurons of the ganglioglioma to be positive for class III β-tubulin, synaptophysin, and chromogranin A, whereas the astrocytic cells stained only for glial fibrillary acidic protein. Most OLCs in the DNT were positive for S-100 protein. This apparently mixed lesion suggests that a close histogenetic relationship exists between DNT and ganglioglioma. We postulate that the pluripotential progenitor cells residing in the subpial granular layer may have given rise to the cortical DNT and to the leptomeningeal ganglioglioma. To our knowledge, this is the first detailed histological, immunochemical and ultrastructural report of a mixed DNT and ganglioglioma. Received: 11 August 1997 / Revised, accepted: 24 November 1997  相似文献   
13.
14.
A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease.  相似文献   
15.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
16.
The histogenesis of stromal cells in hemangioblastoma is inconclusive despite a long-term controversy. An immunohistochemical and ultrastructural study was conducted for 17 cases of cerebellar hemangioblastoma. A wide range of immunohistological markers, targeting epithelial, mesenchymal, endothelial and neuroectodermal tissues, was used. In all cases, the microscopic hallmark characterizing hemangioblastomas, that is, lipid-containing stromal cells and a fine capillary network, known as a reticular variant, was noted. Stromal cells showed a variable immunoreactivity for neuroectodermal markers, such as S-100 protein, CD56, CD57, CD99, and neuron-specific enolase. This result, in conjunction with the absence of immunoreactivity for epithelial, mesenchymal, and endothelial markers, likely suggests neuroectodermal differentiation of stromal cells. In three cases, another component, known as a cellular variant, where epithelioid tumor cells were arranged in nests encircled by capillaries and/or in pseudorosette-like structures, was noted. Glial fibrillary acidic protein-immunoreactivity, which was totally absent in cases only showing the reticular pattern, was noted in two of them, suggesting a distinctive sign of glial differentiation in a proportion of hemangioblastomas. Ultrastructurally, microvilli-like projections in intracytoplasmic vacuoles were demonstrated in stromal cells. This result, taken together with the neuroectodermal hypothesis of stromal cells, suggests that hemangioblastomas may occasionally exhibit morphological similarities to ependymomas.  相似文献   
17.
CD10, also called common acute lymphoblastic leukemia antigen (CALLA), was recently found to be expressed in nonhematopoietic tissues. Although CD10 was also identified in human breast myoepithelial cells, its availability of immunohistochemistry on paraffin sections has not been examined so far. In the present study, we demonstrated CD10 immunohistochemically on paraffin sections of both normal and pathological breast tissues, comparing its staining patterns to those of smooth muscle actin (SMA), which is now commonly used to highlight myoepithelium. CD10 was consistently positive in normal breast myoepithelial cells. CD10 also clearly highlighted myoepithelial cells in intraductal papilloma, adenosis, ductal hyperplasia, fibroadenoma, and phyllodes tumor as well as SMA did. In atypical ductal hyperplasia and ductal carcinoma in situ, continuous, discontinuous, and totally negative stainings of both CD10 and SMA were noted, depending on foci of neoplastic cell nests. However, both stainings clearly demonstrated myoepithelial cells of cancerized acini, being useful in differentiating lobular cancerization from microinvasion. Because SMA was also positive in normal vessels and spindle-shaped stromal cells, CD10, which was negative in vessels, was useful in differentiating myoepithelial cells from thin vascular wall in intracystic lesions with delicate papillae. Although background staining of spindle-shaped stromal cells was also noted in CD10, the positive cell number was less, and the signal was weaker than that of SMA. The absence of myoepithelial cells in invasive ductal carcinomas was more clearly highlighted by CD10 than SMA. We concluded that CD10 could be another useful marker of breast myoepithelial cells on paraffin sections. Combination of CD10 and SMA will provide more sophisticated information about presence or absence of myoepithelial cells in confusing breast lesions.  相似文献   
18.
Rodent and human clinical studies have shown that transplantation of bone marrow stem cells to the ischemic myocardium results in improved cardiac function. In this study, cynomolgus monkey acute myocardial infarction was generated by ligating the left anterior descending artery, and autologous CD34(+) cells were transplanted to the peri-ischemic zone. To track the in vivo fate of transplanted cells, CD34(+) cells were genetically marked with green fluorescent protein (GFP) using a lentivirus vector before transplantation (marking efficiency, 41% on average). The group receiving cells (n = 4) demonstrated improved regional blood flow and cardiac function compared with the saline-treated group (n =4) at 2 weeks after transplant. However, very few transplanted cell-derived, GFP-positive cells were found incorporated into the vascular structure, and GFP-positive cardiomyocytes were not detected in the repaired tissue. On the other hand, cultured CD34(+) cells were found to secrete vascular endothelial growth factor (VEGF), and the in vivo regional VEGF levels showed a significant increase after the transplantation. These results suggest that the improvement is not the result of generation of transplanted cell-derived endothelial cells or cardiomyocytes; and raise the possibility that angiogenic cytokines secreted from transplanted cells potentiate angiogenic activity of endogenous cells.  相似文献   
19.
Four cases of Ischemic enterocolitis without arterio–occlusive lesion were described. Three cases were associated with sigmoid colon carcinomas. Ischemic lesions developed anal to the carcinomas in two cases, and oral to sigmoidostomy to relieve intestinal obstruction by carcinoma in one case. One other case was associated with inguinal hernia. Grossly, ischemic lesions involved relatively short intestinal segments, and the ischemic colonic lesions were not related to teniae coli. Extensive veno–occlusive lesions were discovered in a case of ischemic stricture of the ileum, which had been incarcerated in the right inguinal hernia. Reversible mechanical occlusion of the intestinal vessels caused by transient or recurrent intestinal strangulation is the most probable cause of these ischemic lesions., ACTA PATHOL. JPN. 33: 249–256, 1983.  相似文献   
20.
Accumulation of unfolded and malfolded proteins causes endoplasmic reticulum (ER) stress, stimulating unfolded protein response (UPR) and c-Jun N-terminal kinase (JNK) activation and activating caspase-12 located on the ER. Little is known about the relationship between the ER stress and polyglutamine [poly(Q)] aggregates. Poly(Q)72 repeats [poly(Q)(72)] induced the stimulation of ER stress signals such as JNK activation, upregulation of Grp78/Bip and caspase-12 activation in C2C5 cells. We prepared antiserum against the cleavage site of mouse caspase-12 at D(318) (anti-m12D318), and showed that poly(Q)(72) with perinuclear aggregates, cytoplasmic inclusions and nuclear inclusions stimulated JNK activation and anti-m12D318 immunoreactivity, but poly(Q)(72) with dispersed aggregates and small nuclear aggregates showed a significantly less effect. Poly(Q)(72) and poly(Q)(11) dispersed in cytoplasm did not. Anti-m12D318-positive cells showed apoptotic features. Unlike anti-m8D387 immunoreactivity, the anti-m12D318 immunoreactivity was not coaggregated with poly(Q). Ac-IETD-fmk (caspase-8 inhibitor) and Ac-DEVD-CHO (caspase-3 inhibitor) did not prevent the anti-m12D318 immunoreactivity induced by poly(Q)(72) aggregates. Anti-m12D318 immunoreactivity was detected in caspase-8(-/-) and caspase-3(-/-) mouse embryonic fibroblasts expressing poly(Q)(72) aggregates. Thus, caspase-12 was activated by poly(Q)(72) aggregates via a pathway independent of caspase-8 and caspase-3 activation, and caspase-12 activation was closely associated with poly(Q) aggregate-mediated cell death. Stimulation of ER stress signals may be involved in the pathogenesis of neurodegenerative disorders with poly(Q) expansion.  相似文献   
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