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51.
Undifferentiated (embryonal) sarcoma of the liver (UESL) is a rare pediatric liver malignancy that is extremely uncommon in middle-aged individuals. We studied 2 cases of UESL in middle-aged adults (1 case in a 49-year-old woman and the other in a 62-year-old man) by histology, immunohistochemistry, and electron microscopy to clarify the cellular characteristics of this peculiar tumor. One tumor showed a mixture of spindle cells, polygonal cells, and multinucleated giant cells within a myxoid matrix and also revealed focal areas of a storiform pattern in a metastatic lesion. The other tumor was composed mainly of anaplastic large cells admixed with few fibrous or spindle-shaped components and many multinucleated giant cells. In both cases, some tumor cells contained eosinophilic hyaline globules that were diastase resistant and periodic acid-Schiff positive. Immunohistochemically, the tumor cells showed positive staining for smooth muscle markers, such as desmin, alpha-smooth muscle actin, and muscle-specific actin, and also for histiocytic markers, such as alpha-1-antitrypsin, alpha-1-antichymotrypsin, and CD68. Electron microscope examination revealed thin myofilaments with focal densities and intermediate filaments in the cytoplasm of tumor cells. Our studies suggest that UESL exhibits at least a partial smooth muscle phenotype in middle-aged adults, and this specific differentiation may be more common in this age group than in children. Tumor cells of UESL with smooth muscle differentiation in middle-aged adults show phenotypic diversity comparable to those of malignant fibrous histiocytoma with myofibroblastic differentiation.  相似文献   
52.
Histiocytic necrotizing lymphadenitis without granulocytic infiltration   总被引:12,自引:0,他引:12  
Summary Twenty-seven cases of an unusual necrotizing lymphadenitis previously described only in Japan are reported as occurring in West Germany (23 cases), Iran (1 case), Italy (1 case), Korea (1 case) and Spain (1 case). The lesion frequently develops in the cervical lymph nodes of young women. It is characterized by infiltration of the cortex and/or paracortex by large collections of proliferating histiocytes and is devoid of granulocytes. Complete or, more often, incomplete necrosis of lymphoid tissue is seen in all cases. In cases with incomplete necrosis, the histiocytes are interspersed with pyknotic cells and nuclear debris. Based on the histological findings, the term histiocytic necrotizing lymphadenitis without granulocytic infiltration is proposed. Lesions to be considered in a differential diagnosis are malignant histiocytic neoplasms and necrotizing lymphadenitis with granulocytic infiltration, which is seen in lupus erythematosus and bacterial infections. The aetiology of histiocytic necrotizing lymphadenitis without granulocytic infiltration is still unclear. Some clinical and histological features indicate the possibility of an underlying viral infection.This study was supported by the Kind-Philipp-Stiftung  相似文献   
53.
Experimental autoimmune hepatitis was produced by immunizing Wistar rats with syngeneic liver proteins. Mononuclear cells infiltrating the liver tissue were identified by immunohistochemical techniques using monoclonal antibodies specific for subpopulations of rat lymphocytes. The strong infiltration of CD8+ cytotoxic T lymphocytes (CTL) were found in the portal areas. Subpopulations of mononuclear cells infiltrating the liver, spleen cells and peripheral blood lymphocytes were identified by flow cytometry. Flow cytometric analysis revealed the presence of CD5- and CD8+ lymphocytes in the liver tissues. Mononuclear cells infiltrating the liver were isolated from Wistar rats having autoimmune hepatitis to determine whether those exhibit cytotoxicity against syngeneic hepatocytes; they exhibited cytotoxicity against isolated syngeneic hepatocytes, but failed to lyse K562 cells, syngeneic concanavalin A-activated splenocytes and allogeneic hepatocytes. Depletion of CD8+ T cells significantly reduced the cytotoxic ability of mononuclear cells infiltrating into the liver against syngeneic hepatocytes. These findings support the idea that liver cell injury in experimental autoimmune hepatitis may at least in part be mediated by CTL.  相似文献   
54.
55.
Primary cutaneous B-cell lymphoma in Japanese patients   总被引:1,自引:0,他引:1  
Primary cutaneous B-cell lymphoma (PCBCL) is a rare group of lymphoproliferative disorders. There have been few reports of Japanese patients with PCBCL, so the present study investigated the clinicopathological and immunological features and Bcl-2 gene rearrangement and protein expression in 28 Japanese patients with PCBCL. According to the Revised European-American Lymphoma (REAL) classification, there were 25 diffuse large B-cell lymphomas (DLBCL), one Burkitt type lymphoma, one lymphoblastic lymphoma and one marginal zone cell lymphoma. Of the 25 DLBCL, 17 were in males and eight in females, with an average age of 69.4 years. Follow-up data were available in 19 cases of DLBCL of which seven died and 12 were alive. The overall 5-year survival rate was 61%. Cases of DLBCL involving the legs were found to have poorer clinical outcomes; two of four cases with leg lesions died, with a mean survival of 13 months. Of 14 cases with non-leg lesions, four died, and the mean survival was 38.9 months. Only one case of Burkitt type lymphoma was CD10 positive. Bcl-2 rearrangement was not observed in 13 cases studied by polymerase chain reaction. Bcl-2 expression was observed in nine of 13 cases studied. All five cases with leg lesions exhibited Bcl-2 expression, but four of six cases with non-leg lesions also expressed the protein. These results show that DLBCL is the most frequent subtype of PCBCL in Japanese patients and that the prognosis of Japanese patients with DLBCL is worse than that of reported European cases. The study also found that PCBCL was frequently associated with Bcl-2 expression, which was not site-confined, and that there was no evidence for a follicular center origin of PCBCL.  相似文献   
56.
We compared the expression of cell adhesion molecules (CAMs), cytotoxic granule proteins, and apoptosis-related proteins by immunohistology and in situ terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick end labeling (TUNEL) of 10 cases of cutaneous CD56+ NK/T cell lymphoma with and 6 cases without angiodestruction. Lymphoma cells in cases with angiodestruction frequently expressed CAMs CD2, CD11a, and CD49d and their ligands CD58, CD54, and CD106 and were positive for CD122 and cytotoxic granule proteins TIA1, perforin, and granzyme B. Lymphoma cells in cases without angiodestruction mostly were negative for CD2, CD58, CD54, CD106, and TIA1 and weakly positive for perforin and granzyme B. In the TUNEL method, mean apoptotic indices (AI) for cases with angiodestruction showed a higher percentage than those without angiodestruction. CD95L, CD95, apoptosis-induced cysteine protease CPP32, apoptosis-promoting protein Bax, and proliferating marker (MIB1) frequently were positive in the lymphoma cells of cases with angiodestruction, but there was no expression of apoptosis-inhibitor protein Bcl2. In most cases without angiodestruction, lymphoma cells were positive for CD95L and Bax and negative for CD95, CPP32, and MIB1. CAMs and the 3 cytotoxic granule proteins and an apoptosis pathway might be important factors in the paracrine and autocrine mechanisms of tissue necrosis in cutaneous CD56+ NK/T cell lymphoma.  相似文献   
57.
A rare case of serous papillary cystadenocarcinoma of the ovary showing chondrosarcomatous differentiation in a metastatic deposit late in the clinical course is reported. A 49-year-old female underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy for bilateral ovarian tumors. Histological diagnosis was serous papillary cystadenocarcinoma of both ovaries with lymph node metastasis. After six courses of chemotherapy, she was confirmed to be in complete remission following a second laparotomy. Following additional chemotherapy, a third laparotomy disclosed swollen left inguinal lymph nodes. In one of these nodes, approximately 5.0 cm in greatest diameter, the predominant histological features were: chondrosarcoma of the bone and soft tissue, with small foci of serous papillary adenocarcinoma and squamous epithelium. A histological transition between mesenchymal and epithelial areas was identified. Immunohistochemical positivity for broad-spectrum cytokeratin (AE1/AE3), vimentin, epithelial membrane antigen, and S-100 protein was observed in both chondrosarcomatous and epithelial areas. The current evidence may suggest that the chondrosarcomatous differentiation was derived from the metastatic epithelial component.  相似文献   
58.
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.  相似文献   
59.
A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and la-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeniety of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma. ACTA PATHOL. JPN. 35 : 711–721, 1985.  相似文献   
60.
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