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41.
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998  相似文献   
42.
BackgroundCarpal tunnel syndrome is the most common compression syndrome of the peripheral nerve. Transthyretin amyloidosis and dialysis-related β2-microglobulin amyloidosis are known causes of carpal tunnel syndrome.Case ReportA Japanese woman showed carpal tunnel syndrome 16 years after a domino liver transplantation (DLT) from the donor with hereditary transthyretin amyloidosis. DLT indication was congenital extrahepatic portosystemic shunt, and the patient had been put on maintenance hemodialysis because of chronic kidney disease 6 years before DLT. Moreover, the amyloid precursor protein of the patient was histologically confirmed not to be β2-microglobulin, but transthyretin.ConclusionsThe existence of amyloid was speculated when the patient who underwent DLT from hereditary transthyretin amyloidosis showed carpal tunnel syndrome. Additionally, elucidating the amyloid precursor protein when the patient has another cause of amyloidosis is necessary.  相似文献   
43.
Liver is the largest solid organ in the abdominal cavity, with sinusoid occupying about half of its volume. Under liver disease, hemodynamics in the liver tissue dynamically change, resulting in injury to liver sinusoidal endothelial cells (LSECs). We discuss the injury of LSECs in liver diseases in this article. Generally, in noninflamed tissues, vascular endothelial cells maintain quiescence of circulating leukocytes, and unnecessary blood clotting is inhibited by multiple antithrombotic factors produced by the endothelial cells. In the setting of inflammation, injured endothelial cells lose these functions, defined as inflammatory endotheliopathy. In chronic hepatitis C, inflammatory endotheliopathy in LSECs contributes to platelet accumulation in the liver tissue, and the improvement of thrombocytopenia by splenectomy is attenuated in cases with severe hepatic inflammation. In COVID-19, LSEC endotheliopathy induced by interleukin (IL)-6 trans-signaling promotes neutrophil accumulation and platelet microthrombosis in the liver sinusoids, resulting in liver injury. IL-6 trans-signaling promotes the expression of intercellular adhesion molecule-1, chemokine (C-X-C motif) ligand (CXCL1), and CXCL2, which are the neutrophil chemotactic mediators, and P-selectin, E-selectin, and von Willebrand factor, which are involved in platelet adhesion to endothelial cells, in LSECs. Restoring LSECs function is important for ameliorating liver injury. Prevention of endotheliopathy is a potential therapeutic strategy in liver disease.  相似文献   
44.
Summary Chloroethy1nitrosourea (CENU) chemotherapy has yielded limited benefit on survival of malignant brain tumors. Intracarotid administration of CENU is expected to have the advantage of increasing drug concentration reaching tumors. To understand basic knowledge of intracarotid chemotherapy, we monitor changes of proliferating rate after intracarotid injection of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2chloroethyl)-3-nitrosourea hydrochloride (ACNU), using a bromodeoxyuridine (BUdR) labeling index (LI) in transplanted brain tumors of three cell strains.C6-2 tumor cells were in vitro sensitive to ACNU, and C6-2/ACNU and C6-1 cells were resistant. The drug sensitivity to ACNU was as follows: 11.9 tM in the C6-2 cells, 46.0 M in the C6-2/ACNU cells, and 49.7 M in the C6-1 cells at SD10, which gives 10% survival of clonogenic cells. The intracarotid ACNU at a dose of 30 mg/kg abruptly decreased the LI to 11% (mean) from 36% in C6-2 transplanted tumors. The LI remained low between 12 and 48 hours after, and then increased to the pretreatment level by 96 hours. In contrast, the LI of C6-1 tumors transiently fell to 15% from 42% at 12 hours after the injection, and subsequently increased to 36% at 24 hours and 37% at 48 hours.These results indicate that intracarotid ACNU administration shortly suppresses proliferating activity of tumors and that combined and alternating chemotherapy are mandatory for enhancing effectiveness of brain tumor chemotherapy.  相似文献   
45.
A case of female alcoholic who developed liver cirrhosis with small amounts of alcohol by the common use of contraceptive agent was reported. A case was a 33-year-old female who had complained of systemic edema and jaundice. She had been drinking alcohol, while she had been taking the contraceptive agent from 20-year-old. On admission, she had a large amount of ascites with jaundice. She was diagnosed as liver cirrhosis and hepatic failure by CT scanning of abdomen and laboratory data. Her condition was temporarily improved by the abstinence and the treatment. Since she drank under hospitalization, she had to change the hospital and died after 2 months. She had been drinking for only 10 years. Her cumulative alcohol intake was also very small. She may have developed alcoholic cirrhosis with small amount of alcohol because of common use of contraceptive agent with drinking.  相似文献   
46.
Gender difference of alcohol intake and laboratory data was investigated in 165 Japanese patients with alcoholic liver cirrhosis. Mean age of first drinking and habitual drinking were higher in female. Duration of drinking was shorter in female. Although cumulative alcohol intake was larger in male, mean daily alcohol intake did not differ in both gender. Moreover, daily alcohol intake adjusted to body weight was significantly larger in female. Body mass index, serum levels of total protein, albumin and cholinesterase were significantly decreased in female. Platelet counts on admission did not differ in both gender. However, it was significantly increased in female after one month abstinence. C reactive protein, ammonia and serum levels of total bilirubin were significantly higher in female as compared to male. In conclusion, female alcoholics seems to progress to liver cirrhosis earlier because of high daily alcohol intake adjusted to body weight, poor nutritional condition and inflammation caused by endotoxin.  相似文献   
47.
beta-Catenin and ras oncogenes detect most human colorectal cancer.   总被引:3,自引:0,他引:3  
PURPOSE AND STUDY DESIGN: Recent studies have shown that beta-catenin translocated into the cell nucleus functions like an oncogene. Accumulating evidence suggests that activation of the beta-catenin oncogenic signaling cascade along with its twin, the K-ras cascade, may exert syngeneic or synergistic effects on tumor development and progression. In the study reported here, we analyzed oncogenic beta-catenin activation on the basis of its nuclear accumulation (NA) and compared the results with those of mutational activation of K-ras in 74 patients with colorectal cancer to determine whether the two oncogene-mediated signaling cascades interact. RESULTS: We found two distinct patterns of beta-catenin activation, i.e., diffuse NA in 20 cases (27%) and selective NA at the tumor invasion front (NAinv) in 19 cases (26%). The presence of the NAinv pattern was significantly correlated with advanced Dukes' stage tumor (P = 0.0005) and the presence of distant metastases (P = 0.0064). K-ras proto-oncogene was mutated in the tumors of 31 cases (42%). Activated beta-catenin or K-ras was detected in most (78%) colorectal cancers analyzed, although a weak inverse correlation was found between the activities of the two oncogenes in the tumors. Importantly, most (7 of 8) patients with tumor showing both K-ras activation and the NAinv pattern of beta-catenin activation were in Dukes' stage C at surgery, and half of them developed distant metastases to the liver and lungs. CONCLUSION: The results suggest that although oncogenic activation of beta-catenin and K-ras is independent in the process of clinical cancer development, combined analysis of the two major oncogenes can detect most colorectal cancers and identify a subset of patients with poorer outcomes. Consequently, activation of either or both of these oncogenes may serve as a genetic marker for molecular diagnosis.  相似文献   
48.
PURPOSE: Neovascularization is known to be one of the major characteristics of human hepatocellular carcinoma (HCC). Angiogenin (ANG), originally discovered in a human colon cancer cell line, is a liver-derived polypeptide that shows strong angiogenic activity in vivo. However, the role of ANG on the development of HCC remains unknown. The present study was designed to examine the implication of ANG in the neovascularization of human HCC. EXPERIMENTAL DESIGN: Forty-one HCC patients who had undergone conventional celiac angiography were used in this study. ANG protein expression and microvessel density (MVD) in HCC specimens obtained by liver biopsy or surgical resection were examined by immunohistochemistry, and the levels were quantified by the KS-400 image analyzing system. ANG mRNA expression in liver tissues was evaluated by in situ hybridization. Serum ANG concentrations were measured by an ELISA. Survival rates were calculated using the Kaplan-Meier method. RESULTS: Immunohistochemistry and in situ hybridization showed greater increments of ANG protein expression and mRNA expression, respectively, in HCC tissues than in the surrounding nontumorous tissues. MVD within tumorous tissues increased according to dedifferentiation of the histological grade of HCC, showing a significant correlation (r = 0.877, P = 0.0009) with ANG expression levels. Mean +/- SD serum ANG levels of healthy subjects and chronic hepatitis (CH) patients were 362.3 +/- 84.1 ng/ml and 331.9 +/- 133.8 ng/ml, respectively, with no significant difference. Serum ANG levels of liver cirrhosis patients (242.4 +/- 126.9 ng/ml) were lower than those of healthy subjects or CH patients and decreased as the fibrosis grade advanced. In HCC patients, despite the cirrhotic background, serum ANG levels increased as the tumor vascularity increased (197.8 +/- 64.9 ng/ml for hypovascular, 326.7 +/- 148.6 ng/ml for hypervascular, and 405.0 +/- 121.3 ng/ml for very hypervascular), in good accordance with histological grading, and significantly decreased (P = 0.015) after successful treatment with transcatheter arterial embolization or percutaneous ethanol injection. HCC patients were conventionally divided into two groups according to the serum level of ANG, those with values higher than the mean level (332.9 +/- 143.8 ng/ml) and those with values lower than the mean,; the 5-year survival rate of the latter group was determined to be significantly higher than that in the former group. CONCLUSIONS: These results suggest that ANG is one of the neovascularization defining factors of HCC. Thus, measuring serum ANG may assist in monitoring the disease, and targeting ANG may provide a new strategy for treating advanced HCC.  相似文献   
49.
Subependymoma of the septum pellucidum: Characterization by PET   总被引:1,自引:0,他引:1  
We report the evaluation of a subependymoma of the septum pellucidum by positron emission tomography (PET) with analysis of 18F-fluorodeoxyglucose (FDG)kinetics. The tumor showed exceedingly low rates of glucose metabolism (rCMRG1) and kinetic constants (K1, K2, and K3). This hypometabolism indicates low cellular density and slow growth.  相似文献   
50.
A 53-year-old woman had shown repeated, partial responses to chemotherapy for large, multiple liver metastases of sigmoid colon cancer. After a partial response to 5-fluorouracil plus leucovorin therapy, an 89.7% reduction of the 5-fluorouracil-resistant metastatic tumor was achieved by giving CPT-11 (irinotecan) at a dose of 100 mg/body per week. We suggest that CPT-11 should be recommended as an effective second-line treatment for unresectable liver metastases of colon cancer, after 5-fluorouracil-based chemotherapy.  相似文献   
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