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51.
Takaaki Ohmori Kazuyo Okada Ryo Tabei Keisuke Sugiura Shinji Nabeshima Hiroji Ohoka Masaki Okamoto 《Pathology international》1994,44(4):333-337
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin. 相似文献
52.
Massimo Pignatelli Tareq W. Ansari Pat Gunter Dan Liu Shinji Hirano Masatoshi Takeichi Günter Klppel Nicholas R. Lemoine 《The Journal of pathology》1994,174(4):243-248
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer. 相似文献
53.
54.
T cell immunity and primary biliary cirrhosis 总被引:4,自引:0,他引:4
T lymphocytes play a pivotal role in the autoimmune response in primary biliary cirrhosis (PBC). Recent studies have shown that there is overlapping in the PDC-E2-specific T and B cell epitopes. In addition, helper T and cytotoxic T cell epitopes all contain a shared peptide sequence. In addition, recognition of exogenous antigens including bacterial antigens by autoantigen-specific T cell and the mechanism of molecular mimicry provide a clue to clarifying the pathogenesis of PBC. Furthermore, the findings that autoantigen-immune complexes cross present and also that the presentation of autoantigen is of a higher relative efficiency, define a unique role of autoantibodies in the pathogenesis of the autoimmune disease. The mechanism of immune-mediated bile duct damage in PBC, including the possible role of T cell-mediated cytotoxicity and molecular mimicry is discussed. 相似文献
55.
Atsuko Masunaga Isamu Sugawara Hisayoshi Nakamura Tsuyoshi Yoshitake Shinji Itoyama 《Pathology international》1997,47(12):842-847
Subsets of thymic epithellal cells were examined Immuno-histochemically to determine whether or not their pheno-types change during thymic growth and at early involution in terms of cytokeratin (CK) expression. Five monoclonal antibodies specific for CK4, CK8, CK13, CK18 and CK19 were used and applied for 16 neonatal, three Infantile and one adult thymus speeimen, which had been obtained at autopsy, that were normal macroscopically and microscopicaily. CK4, CK8, CK13, CK18 and CK19 were expressed simultaneously in the cortex, medulla and subcapsular area with the exception of CK4, which showed expression on the adult thymus. Light and electron microscopy showed that CK8 and CK19 expression was overlapped. Thus, It was thought that CK8 and CK19 formed complexes in the cytoplasm of thymic epithelial cells. The Immunoreactivity to CK4, CK13 and CK18 were attenuated or disappeared In the subcapsular area during the early involution stage. Interestingly, two patterns of CK18 expression were observed in the neonatal and Infantile thymus tissues, which Indicated that the thymic microenvironment was changeable even under normal conditions. 相似文献
56.
Yuichi Takeoka Shao-Yuan Chen Richard L. Boyd Koichi Tsuneyama Nobuhisa Taguchi Shinji Morita Hisashi Yago Seishi Suehiro Aftab A. Ansari Leonard D. Shultz M. Eric Gershwin 《Clinical & developmental immunology》1997,5(2):79-89
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis
through a highly coordinated and complex series of cellular and cytokine interactions. A direct
corollary of this is that abnormalities within the microenvironment could be of etiologic
significance in T-cell-based diseases. Our laboratory has developed a large panel of
monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial
markers in the thymus. We have taken advantage of these reagents to characterize the
thymic microenvironment of several genetic strains of mice, including BALB/cJ,
C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph
me/Hcph me, and
ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control
mice, including strains of several backgrounds, have a very consistent phenotypic profile
with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells
in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix.
In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex
and medulla at both the structural and cellular levels. These phenotypic data suggest
that abnormalities in interactions between developing thymocytes and stromal cells characterize
disease-prone mice. 相似文献
57.
Fukumoto S Tamaki Y Shirafuji H Harakawa S Suzuki H Xuan X 《Clinical and diagnostic laboratory immunology》2005,12(4):557-559
This is a report of a vaccine trial directed against Babesia gibsoni infection in dogs with the use of the recombinant antigen P50. Dogs immunized with P50 showed partial protection manifested as a significantly low level of parasitemia. The results indicated that P50 is a primary vaccine candidate molecule against canine B. gibsoni infection. 相似文献
58.
Kusumi T Nishikawa S Tanaka M Ogawa T Jin H Sato F Toh S Hasegawa T Kijima H 《Pathology international》2005,55(12):802-806
Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor. Reported herein is a case of LGFMS arising in the big toe. The patient was a 58-year-old man who underwent excision of the tumor. The tumor was well-demarcated. Histologically, there were proliferating spindle-shaped tumor cells arranged in a whorled growth pattern, and the stroma showed hyalinized collagen bundles and a myxoid matrix. Nuclear mitotic figures were conspicuous in part. A large rosette-like structure with hyalinized stroma was found, which is characteristic of LGFMS. The differential diagnosis included tumor occurrence in adults; tending to arise in distal extremities; and having bland fibromyxoid histological features, such as fibroma of tendon sheath, low-grade myxofibrosarcoma and acral myxoinflammatory fibroblastic sarcoma. It was not possible to detect the FUS/CREB3L2 and FUS/CREB3L1 fusion genes from the formalin-fixed and paraffin-embedded tissue, although the histological features of the present case were typical of LGFMS. LGFMS may become more common with time, and unique cases may accumulate. 相似文献
59.
Role of macrophage migration inhibitory factor in otitis media with effusion in adults 总被引:4,自引:0,他引:4
Kariya S Okano M Aoji K Kosaka M Chikumoto E Hattori H Yuen K Nishioka S Nishioka K Nishizaki K 《Clinical and diagnostic laboratory immunology》2003,10(3):417-422
Otitis media with effusion (OME) is one of the most common ear diseases. Bacterial endotoxins and several inflammatory cytokines appear to be involved in the pathogenesis of OME in children; however, little is known of the immunological aspects of the onset of OME in adults. We sought to determine the presence of macrophage migration inhibitory factor (MIF) as well as interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), RANTES (regulated upon activation, normal T-cell expressed and presumably secreted), and endotoxin in middle ear effusions (MEEs) from adult patients with OME. In addition, the levels of MIF in MEEs from adults and children were compared. MEE was obtained from 95 adults and 11 children. The levels of MIF, IL-1beta, TNF-alpha, and RANTES were determined by enzyme-linked immunosorbent assay, and the concentrations of endotoxin and total protein were determined by the Endospec assay and bicinchoninic acid assay, respectively. MIF was detected in 97.9% of the MEEs from adults, while endotoxin, IL-1beta, TNF-alpha, and RANTES were detected in 96.8, 12.6, 5.3, and 43.9%, respectively. In addition, the level of MIF was significantly higher than those of endotoxin, IL-1beta, and TNF-alpha. A positive correlation between the levels of MIF and endotoxin was observed. MIF and endotoxin were detected in 81.8 and 72.7%, respectively, of the MEEs from the children. The level of MIF was significantly higher in the children, and conversely that of endotoxin was significantly higher in the adults. These results suggest that the interaction between MIF and endotoxin may promote fluid collection in the middle ear, particularly in adults. 相似文献
60.
Satoda T Hiyama S Karukaya E Hayashida K Uchida T 《Kaibogaku zasshi. Journal of anatomy》2003,78(3):95-101
It is difficult to teach students about the embryological transformation of the branchial arteries. In mammals, six pairs of branchial arteries develop, but all are not present at the same embryological stage. The first, second, fifth and a part of right sixth branchial artery disappear early in embryological development. The remaining third, fourth and sixth branchial arteries mainly constitute the arterial system of the breast. The aorta and pulmonary trunk are derived from the truncus arteriosus. Because of the complexity of this developmental process, we have devised a user-friendly model in order to assist with educational presentations. In this model, the shrinkage of a vessel has been represented by inserting a wire inside of the hose representing the artery. Degenerated or disappearing parts of the vessel are removable by using hooks and Velcro tape. Branchial arteries, truncus arteriosus, aortic sac and dorsal arteries are represented by different colors. The descent of the heart is represented by the relational change between larynx and heart. Additionally we represented the vagus nerve and recurrent laryngeal nerve by using strings. The right vagus nerve can move dorsally and the left ventrally by rotating the digestive tract. The right recurrent laryngeal nerve can move superiorly to hook around the right subclavian artery, and left recurrent laryngeal nerve can hook around the ductus arteriosus formed by the left sixth branchial artery. 相似文献