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41.
Adhesion polypeptides are useful for the prevention of peritoneal dissemination of gastric cancer 总被引:3,自引:0,他引:3
Tasuku Matsuoka Kosei Hirakawa-YS Chung Masakazu Yashiro Shigehiko Nishimura Tetsuji Sawada Ikuo Saiki Michio Sowa 《Clinical & experimental metastasis》1998,16(4):381-388
We examined the effect of adhesion polypeptides on the adhesion and invasiveness of gastric cancer cell lines. We previously reported the establishment of an extensively peritoneal-seeding cell line, OCUM-2MD3, from a poorly seeding human scirrhous gastric carcinoma cell line, OCUM-2M. Both 21 and 31 integrin expression was markedly increased on OCUM-2MD3 cells compared with OCUM-2M cells, and the ability of OCUM-2MD3 cells to bind to the extracellular matrix (ECM) was also significantly higher than that of OCUM-2M cells. The adhesion polypeptides, YIGSR and RGD, and two RGD derivatives significantly inhibited the adhesion of OCUM-2MD3 cells to the submesothelial ECM, while not inhibiting the adhesiveness of OCUM-2M cells and two well differentiated human gastric cell lines, MKN-28 and MKN-74. The YIGSR and RGD peptides also significantly inhibited the invasiveness of OCUM-2MD3 cells. The survival of nude mice with peritoneal dissemination given YIGSR sequenc e intraperitoneally was obviously longer than that of untreated mice. The survival of mice treated with RGD was also improved, and this effect was increased using the RGD derivatives, poly(CEMA-RGDS) and CM-chitin RGDS. These polypeptides appear to block the binding of integrins, which are expressed on OCUM-2MD3 cells, to the submesothelial ECM, and consequently inhibit peritoneal implantation. The peritoneal injection of adhe-sion polypeptides may be a new therapy against the dissemination of scirrhous gastric cancer, and may be useful for the prevention of dissemination in high-risk patients. © Rapid Science Ltd. 相似文献
42.
Ultrastructural,immunohistochemical and biochemical studies on amylase and ACTH producing lung cancer 总被引:1,自引:0,他引:1
Yutaka Yoshida Michio Mori Tomoko Sonoda Fumio Sakauchi Hiroyuki Sugawara Akira Suzuki 《Virchows Archiv : an international journal of pathology》1985,408(2-3):163-172
Summary Tumour tissue from a lung cancer patient who showed elevated serum amylase and adrenocorticotropin (ACTH) was studied ultrastructurally, immunohistochemically and biochemically. Histologically the tumour was a small cell carcinoma. On electron microscopic examination the tumour cells contained large zymogen-like granules within the cytoplasm. Furthermore, cells which possessed many small dense core granules of the endocrine type were also observed. It was of interest that the large zymogen-like granule-containing tumour cells had microvilli at the apical border, connected by desmosomes and forming lumina showing adenocarcinomatous differentiation. Electrophoretic analysis of the serum revealed that the major elevated amylase was of the salivary type with minor components. Immunostaining clearly demonstrated that most of the tumour cells possessed immunoreactive ACTH, whereas salivary amylase was only found in occasional clusters of the tumour cells. The results seem to indicate that the tumour showed both endocrine and exocrine characteristics - an amphicrine carcinoma, expressing amylase and ACTH simultaneously. 相似文献
43.
Takashi Minase Minoru Ogasawaea Takanori Kikuchi Hideaki Hirai Akira Suzuki Chieko Nishio Katsuhiro Ogawa Kokichi Kikuchi Michio Mori 《Pathology international》1985,35(3):711-721
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
44.
Takashi Wakabayashi Michio Horiuchi Sachiyo Kawamoto Hiroyuki Onda 《Pathology international》1984,34(3):481-488
Ultrastructure of megamitochondria in mouse hepatocytes induced by cuprizone was analyzed in the light of the fusion of inner mitochondrial membranes. Hepatic parenchymal cells of mice fed with a 0.5% cuprizone-diet for 7–8 days were characterized by megamitochondria with numerous cristae including disoriented, shorter ones than those of the control and those in vesicular configuration. After feeding the animals with cuprizone for 15–16 days, megamitochondria increased their sizes further and the number of cristae decreased drastically. Numbers of cristae based on a unit-mitochondrial area were 41.3$pL10.8 for the former type of cristae-enriched megamitochondria and 3.8 $pL 1.8 for the latter type of megamitochondria with the value of 23.9 $pL 6.2 for the control. Considering the content of cytochromes in megamitochondria previously reported, these results might suggest that the fusion and defusion of inner mitochondrial membrane take place along with the fusion of outer membranes during the megamitochondrial formation. ACTA PATHOL. JPN. 34: 481–488, 1984. 相似文献
45.
Hiroshi Kaneko Haruto Hj Shinobu Ishikawa Michio Kikuchi 《Pathology international》1977,27(3):375-385
A large tumor massively occupying the left pleural cavity had the Andings of both typical carcinoid and oncocytoma which were thought to be of bronchogenic origin. The ultrastructural observation of the tumor revealed a mixture of rod-shaped granules in addition to usual round neurosecretory ones. In the nuclei of dark cells of the oncocytoma, a latticed or hatched structure was detected. Besides two adenomas and hyperplastic foci of large acidophilic cells in the thyroid, a black adenoma and cortical adenoma in the adrenal gland, were detected. Moreover, there was an ectopic adrenal gland in the retroperitoneum. Briefly it was suggested that the bronchial carcinoid presented may be related to multiple endocrine adenomatosis. 相似文献
46.
Intra and extracellular localization of alpha-fetoprotein (AFP) has been studied by an indirect peroxidase labeled antibody method using 12 cases of human hepatocellular carcinoma (HCC). With light microscopic observation, positive immuno-staining for AFP was observed in 6 out of 12 cases and demonstrated as granular or diffuse deposits in the cytoplasm of neoplastic hepatocytes. In electron microscopic studies, 8 cases showed the positive immuno-staining for AFP in the neoplastic hepatocytes. Intracellular antigen was well circumscribed within certain cell organelles with the positive immuno-staining for AFP being observed in perinuclear space, cisternae of rough endoplasmic reticulum (RER), Golgi complexes, and secretory vesicles. In addition, the positive immuno-staining for AFP was observed in bile canaliculus-like space in most cases with increased levels of serum AFP and in some cases which showed normal levels of serum AFP. Furthermore, the positive immuno-staining for AFP was also observed in intercellular, Disse's-like and sinusoid-like spaces, and micropinocytotic and lysosome-like vesicles in the endothelial cells in a few cases which showed excessively high value of serum AFP. ACTA PATHOL. JPN. 37:915–928, 1987. 相似文献
47.
Suzuki K Kokai Y Sawada N Takakuwa R Kuwahara K Isogai E Isogai H Mori M 《Virchows Archiv : an international journal of pathology》2002,440(3):318-324
Helicobacter pylori induces severe neutrophilic infiltration in the lamina propria of the stomach, which leads to gastritis in humans. The possible involvement of a paracellular route for bacterial nutrients and etiologic agents that may play an important role in colonization of the bacteria and cause gastritis has been suggested. To study the functions of the paracellular barrier of gastric surface epithelium, SS1, a strain of H. pylori adapted to the murine stomach, was inoculated into the stomachs of C57BL/6 mice. At 4 months after inoculation, SS1 had achieved a high level of colonization (10(6)-10(7) colony-forming units/g tissue) associated with neutrophilic infiltration in the lamina propria of the junctional zone. Disruption of the paracellular barrier was observed in the SS1-infected stomachs, as revealed by the invasion of a lanthanum tracer into the paracellular space of the surface epithelium. Only 2% of junctions were permeable in control stomachs, whereas 72% of the paracellular barrier was disrupted in the SS1-infected gastric epithelia. Furthermore, distribution of tight junction-related molecules such as 7H6 antigen, occludin, and cortical actin was affected in the surface epithelium by SS1 infection. The linear expression pattern of occludin was disrupted and became irregular or punctuated. The 7H6 antigen accumulated as aggregates in the apical portion of the surface epithelium and cortical actin became irregular and punctuated. Taken together, these results indicate that infection by SS1 directly or indirectly caused an increase in paracellular permeability and altered the localization of tight junction-related molecules of the gastric surface epithelium. This observation suggests that the paracellular pathway may play a significant role in establishing H. pylori-induced gastritis in the clinical setting. 相似文献
48.
Koga H Sakisaka S Yoshitake M Harada M Kumemura H Hanada S Taniguchi E Kawaguchi T Kumashiro R Sata M 《International journal of molecular medicine》2002,9(6):621-626
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
49.
Amagai T Mouri T Kirii K Hori T Kaneko M Ohkawa H 《Clinical and experimental pharmacology & physiology. Supplement》2002,(29):S19-S22
1. Biliary atresia (BA), as a common disease in Japan, and cystic fibrosis (CF), as an extremely uncommon disease in Japan, were selected to assess the clinical significance of measurement of energy expenditure (EE). 2. Energy expenditure was significantly higher in children with BA than in normal children. 3. Measurement of EE in BA lead to clues to resolving its mechanism by novel assessment of interleukin-6 and leptin. 4. Energy expenditure in children with CF is also higher, but this has been addressed by nutritional intervention with additional calories. 5. Individualization of EE measurement is necessary in the analysis of pathological mechanisms and nutritional management of patients with both common and uncommon diseases. 相似文献
50.
Fujihiko Suzuki Akira Saito Kazuhisa Ishii Akihiko Yamamura Michio Matsumoto Masanobu Eguchi Masataka Tanno Kunio Mizuguchi Yoshinori Hosokawa Koichi Suda Sachiko Takase 《Medical molecular morphology》1996,29(1):48-51
A rare placental site trophoblastic tumor (PSTT) in a 39-year-old female was studied. This tumor, protruding into the uterine cavity, was histologically similar to tumors in previously reported cases of PSTT. Ultrastructurally, the characteristic finding was the presence of perinuclear filaments. Also, the tumor cells were strongly positive for hPL by immunohistochemical method. These findings suggest that this was a tumor caused by neoplastic proliferation of the extravillous intermediate trophoblast. 相似文献