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991.
FR235222, a novel immunosuppressant which possesses potent inhibitory effects on the activity of mammalian histone deacetylases (HDACs), has been isolated from the fermentation broth of a fungus, Acremonium sp. No. 27082. FR235222 exhibited marked immunosuppressive effects on mouse ex vivo splenic T-lymphocyte proliferation, mouse delayed type hypersensitivity (DTH) response, rat adjuvant-induced arthritis (AA) and rat heterotopic cardiac transplantation. These results showed potential clinical use of this compound as a new type immunosuppressant in the fields of autoimmune diseases and organ transplantations.  相似文献   
992.
Three mouse strains (BALB/c, ICR, and C3H/He) were injected intratracheally with house dust mites (Der f) four times at 2-week intervals during exposure to diesel exhaust (DE) or clean air for 8 weeks. Der f treatment caused eosinophilic inflammation and proliferation of goblet cells in the airways of the three strains. DE + Der f caused a further increase of eosinophils in BALB/c and ICR mice, but not in C3H/He mice. DE + Der f significantly increased interleukin (IL)-5; regulated on activation, normal T cell expressed, and presumably secreted (RANTES); eotaxin, monocyte chemotactic protein-1 (MCP-1); and macrophage-inflammatory protein-1 alpha (MIP-1 alpha) in all three strains. However, the protein of IL-5 decreased more in C3H/He mice treated with DE + Der f than in mice treated with Air + Der f. The levels of IL-5 in lung tissues corresponded to the pathological changes by Der f and/or DE treatment. The levels of MCP-1 and MIP-1 alpha in the three strains corresponded to the accumulation of lymphocytes in the airway. The adjuvant effect of DE on IgG1 production was observed in the ICR and C3H/He mice. These results suggest that the murine strain differences in the production of eosinophilic airway inflammation by DE + Der f is related to differences in local expression of IL-5, eotaxin, and IgG1 production. The enhancing effects of DE exposure may be mediated mainly by local IL-5.  相似文献   
993.
A case for primary gastrointestinal stromal tumor (GIST) is described with reference to its ultrastructural characteristics and mutation within the exon 11 of c-kit gene. A forty-seven years old woman complaining of dysphasia was examined by endoscopy, which depicted a submucosal tumor (70 mm in diameter) with ulcerations at the fundus of the stomach. Histopathologically, the tumor cells had large nuclei and eosinophilic cytoplasm and were frequently during mitosis phase. The tumor cells were immunopositive for KIT, CD 34 and vimentin, suggesting their fibroblast-like characteristics. In contrast, desmin and S-100, a smooth muscle and an enteroglial marker, were not immunopositive within the cells. At least 30 % of the tumor cells possessed MIB-I and 20 % of them possessed p53, which are compatible with fast development of the tumor. By electron microscopy, the tumor cells possessed large oval nuclei, abundant mitochondria, caveolae and smooth endoplasmic reticulums, while no gap junctions were seen on the cells: The tumor cells thus possessed interstitial cells-like characteristics at least in part. DNA mutation search for the tumor cells however realized no gain-of-function mutation within the exon 11 of the c-kit gene, suggesting existence of other mechanism for neoplasmic growth of the tumor cells classified as gastrointestinal stromal tumors.  相似文献   
994.
Circulating DNA can be isolated from serum of patients with various carcinomas and p53 mutation can be observed in colorectal carcinoma. The aim of this study was to investigate the correlation between p53 mutation in DNA extracted from colorectal carcinoma and that in DNA extracted from serum of patients with colorectal carcinoma. The clinical significance in molecular detection of p53 mutation in serum of patients with colorectal carcinomas was also investigated. DNA was extracted from tumors and non-tumorous colorectal tissues of 46 patients with single sporadic colorectal carcinomas of stage I (n=6), stage II (n=18), stage III (n=15), and stage IV (n=7) according to the TNM classification. Circulating DNA was also extracted from the serum of the 46 patients with colorectal carcinoma and from 7 healthy volunteers for normal control. Mutations of the p53 gene were analyzed using a fluorescence-based polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) method. DNA sequences were determined in DNA fragments with shifted peaks by SSCP methods. Mutations in tumors were found in 22 (48%) of 46 patients, and mutations in serum were found in 3 (14%) of these 22 patients. Of 4 patients with stage IV disease, 3 (75%) had serum p53 mutation and the mutation pattern of these 3 patients was the same in both tumor and serum. No correlation was seen between p53 mutation in serum and the level of serum DNA. There was no significant difference between the presence of p53 mutation in serum and tumor size, depth of invasion, vascular invasion, or lymph node metastasis. However, liver metastasis showed significant difference (p=0.0026). The presence of p53 mutation in serum was associated with a clinically advanced stage accompanied by liver metastasis.  相似文献   
995.
We report that single agent therapy with trastuzumab had a significant effect on metastatic breast cancer, which was confirmed to be HER2 positive by Herceptest showing 2+staining, and gene amplification positively detected by FISH analysis. A 48-year-old woman underwent extended radical mastectomy (T2N0M0 stage II). Three years after the operation supraclavicular lymph node metastasis was noted. Bone scintigraphy showed metastases to the left ribs 5 years after operation. She was treated with chemo-endocrine therapy, but nonetheless could not bear the back pain caused by the bone metastases. Another chemotherapy course could not be permitted because of leukopenia. Immunohistochemistry (IHC) analysis with Herceptest showed 2+staining for HER2 and FISH analysis showed gene amplification of HER2. We started single agent therapy with trastuzumab and she subsequently had remarkably improved back pain. Physical examination and ultrasonography showed disappearance of the previous palpable supraclaviclar lymph nodes. Serum tumor markers were also reduced after the first administration of trastuzumab. The patient is currently alive, with no further progression of the lymph node or bone metastases.  相似文献   
996.
Hepatoma-derived growth factor (HDGF) is highly expressed in tumor cells, and stimulates their proliferation. In the present study, we investigated the role of HDGF in tumorigenesis and elucidated the mechanism of action. Stable transfectants of NIH3T3 cells overexpressing HDGF did not show significant anchorage-independent growth in soft agar assay. However, these stable transfectants overexpressing HDGF generated sarcomatous tumors in nude mice. These tumors were red-colored macroscopically, and histologically showed a rich vascularity. Immunohistochemical analysis using CD31 antibody showed new vessel formation. Recombinant HDGF stimulated proliferation of human umbilical vein endothelial cells in a dose-dependent manner, and stimulated tubule formation. Furthermore, vascular endothelial growth factor (VEGF) was detected immunohistochemically in the tumor tissues. Transient expression of HDGF induced both VEGF gene and protein expression as demonstrated by a reporter assay using VEGF gene promoter. The administration of anti-VEGF neutralizing antibody significantly suppressed, but did not block, the tumor growth of HDGF-overexpressing cells in nude mice. Thus, these findings suggested that HDGF-induced tumor formation in vivo involves induction of VEGF as well as direct angiogenic activity.  相似文献   
997.
We report a case of recurrent solitary fibrous tumor with associated hypoglycemia, the "Doege-Potter syndrome." These are rare tumors with a 12-13% rate of malignancy. The syndrome of hypoglycemia is seen in less than 5% of the cases, and the associated tumors are large with a high mitotic rate. The cause of hypoglycemia is related to insulin-like growth factors produced by these tumors. Resection in many cases is curable with resolution of the hypoglycemia. We discuss the different signs and symptoms and literature evidence of treatment options and follow-up.  相似文献   
998.
Magnetic response imaging has demonstrated increased signal intensities within the basal ganglia in patients with hepatic encephalopathy; the densities are considered to represent manganese deposition. We measured whole blood manganese concentrations in nine children with congenital portosystemic venous shunts detected by screening tests for galactosaemia. Beyond 1 year of age, these patients showed significantly higher manganese concentrations than controls (2.40 ± 0.43 versus 1.48 ± 0.38 μg/dl; P=0.0001). Four of the nine patients were studied by magnetic response imaging. T1-weighted images showed increased signal intensities in the basal ganglia of those four patients, suggesting manganese accumulation. Conclusion Children with congenital portosystemic venous shunts showed manganese elevations in blood and magnetic response imaging changes in the basal ganglia. These children should avoid excessive manganese intake. Received: 11 September 2000 / Accepted: 30 November 2000  相似文献   
999.
BACKGROUND/AIMS: Inflammatory cytokines, such as interleukin-1 beta and tumor necrosis factor-alpha, which activate neutrophils, contribute to hepatic warm ischemia-reperfusion injury. However, the role of the cytokines in hepatic microcirculation immediately after reperfusion is still unclear. This study was carried out to investigate whether FR167653, a dual inhibitor of interleukin-1 beta and tumor necrosis factor-alpha, attenuates hepatic microcirculatory disturbance at the initial phase of reperfusion following liver ischemia. METHODOLOGY: Adult mongrel dogs were subjected to 90 minutes of liver ischemia by a Pringle's maneuver under portosystemic bypass. The animals were divided into two groups: a control group (n = 10), subjected to hepatic warm ischemia only, and a FR167653 administered group (n = 5), which received 1 mg/kg/h FR167653 for 4 hours since 30 minutes before the ischemia to 2 hours after the reperfusion continuously. Seven days animal survival, hepatic tissue blood flow, liver function test, hepatic venous blood concentration of endothelin-1 and plasminogen activator inhibitor-1, liver tissue biochemistry, and histopathology were analyzed. RESULTS: The treatment with FR167653 attenuated microcirculatory disturbance, lessened liver injury, enhanced adenine nucleotides resynthesis, and improved animal survival after liver ischemia. In addition, FR167653 significantly inhibited release of both endothelin-1 and plasminogen activator inhibitor-1 from the liver cells. CONCLUSIONS: These results suggest that the inflammatory cytokines induce microcirculatory disturbance in the initial phase of reperfusion following liver ischemia.  相似文献   
1000.
BACKGROUND/AIMS: Intractable ascites is one of the serious complications after hepatectomy. Only little is known about their effect on postoperative ascites in patients with liver cirrhosis although beta-blockers have been used for cirrhotic complications including ascites. METHODOLOGY: Here, we report five cases of intractable ascites after hepatectomy, which were treated by propranolol (1 mg/kg/body). RESULTS: In three patients, plasma renin activity and aldosterone concentrations were markedly increased before propranolol administration, but fell to normal levels thereafter. Ascites subsided in all subjects except one, who developed cardiac dysfunction. CONCLUSIONS: Beta-blockers might be a promising drug for intractable ascites in cirrhotic patients undergoing hepatectomy.  相似文献   
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