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排序方式: 共有1299条查询结果,搜索用时 15 毫秒
81.
Growing evidence demonstrates that hepatitis B virus (HBV) integration and resulting insertional mutagenesis play an important role in cell growth or maintenance in hepatocellular carcinomas (HCCs). To determine if HBV integration occurs and affects cellular genes at such a stage of infection, we analysed viral-host junctions in chronic hepatitis tissues without HCC using PCR amplification with primers specific to human Alu-repeat and HBV. We obtained 42 independent viral-host junctions from six patients examined and identified chromosomal locations for 20 of the 42 junctions. In six clones, each integration apparently affected a single gene. These six candidate genes included one known tumor suppressor gene, three human homologs of drosophila genes that are critical for organ development, one putative oncogene and one recently found chemokine. Our data, together with previously reported HBV integrants in HCCs, suggested preferential HBV integration into chromosome 3 (P = 0.022). Our virus-tagging approach provided (a) firm evidence of HBV integration in hepatocytes at an early stage of chronic infection and (b) revealed cellular genes possibly affected by HBV integration and potentially involved in early steps of the process leading to carcinogenesis. 相似文献
82.
Expression of matrix metalloproteinases (MMPs) in cultured hepatocellular carcinoma (HCC) cells and surgically resected HCC tissues 总被引:6,自引:0,他引:6
Ogasawara S Yano H Momosaki S Nishida N Takemoto Y Kojiro S Kojiro M 《Oncology reports》2005,13(6):1043-1048
Matrix metalloproteinases (MMPs) relate to the growth and infiltration of cancer cells, but the frequency and amount of their expression are not yet fully examined in hepatocellular carcinoma. Expression of MMPs (MMP-2, MMP-7, MMP-9, MT1-MMP, MT2-MMP, MT3-MMP) and tissue inhibitors of metalloproteinase (TIMP: TIMP-1, TIMP-2) was investigated on cultured hepatocellular carcinoma (HCC) cells and surgically resected HCC tissues. The cultured cells and tissues expressed MMPs and TIMPs at various degrees, and high expression was observed for MMP-2, MMP-9, MT1-MMP and TIMP-2. Expression of MMP-7, MT2-MMP and TIMP-1 was found at a low frequency and a low amount in both the cells and the tissues. MMP-2 was expressed in various cells: HCC cells, vascular wall and sinusoidal endothelial cells in the cancer area of surgically resected tissues; and hepatocytes, bile duct cells, vascular wall, macrophages and Kupffer cells in the non-cancerous area. MMPs and TIMPs were expressed at a relatively high frequency in hepatocytes of the cancerous area and surrounding non-cancerous area as well as in the other cells and tissues. MMPs and TIMPs may be involved in the progression of hepatocellular carcinoma including the infiltration of cancer cells. 相似文献
83.
Efficacy of lamivudine therapy for decompensated liver cirrhosis due to hepatitis B virus with or without hepatocellular carcinoma 总被引:1,自引:0,他引:1
Hiraoka A Michitaka K Kumagi T Kurose K Uehara T Hirooka M Yamashita Y Kubo Y Miyaoka H Iuchi H Okada S Ohmoto M Yamamoto K Horiike N Onji M 《Oncology reports》2005,13(6):1159-1163
The prognosis for patients with decompensated hepatitis B virus (HBV) related liver cirrhosis (LC-B), especially for those with LC-B complicated with hepatocellular carcinoma (HCC), is poor. We investigated the effects of lamivudine in patients with decompensated LC-B, with and without HCC. Decompensated LC-B patients (n=55) with Child-Pugh classification scores (CPS) >7 points were enrolled. All were admitted to the hospitals of the authors between January 1997 and December 2004. Decompensated cases due to a severe exacerbation of hepatitis with CH-B and patients with HCC showing an extra hepatic metastasis or portal vein tumor thrombus were excluded. Some 19 cases (including 5 cases complicated with HCC at the start of therapy) were treated with lamivudine at 100 mg/day (L group), and 36 (including 7 cases with HCC at time of admittance) were treated without lamivudine (non-L group). The median of CPS points in the L group was higher than that of non-L group (11 points versus 9 points, p<0.02). Prothrombin time (%), albumin, ascites, CPS, and HBV-DNA quantity were each significantly improved after 6 months in the L group (p<0.05). A mutation in the YMDD motif was observed in 5 patients in the L group, however liver function did not deteriorate. Further, the survival rate was significantly higher in the L group (p<0.05). HCC was found in 3 L group and 4 non-L group patients during the study. In the L group, all patients complicated with HCC were treated repeatedly or until cured, whereas 91% of those in the non-L group could not be treated (p<0.01). Our results suggest that lamivudine is a useful and important therapy for patients with decompensated LC-B with and without HCC, as well as those who are restricted from having liver transplantation. 相似文献
84.
85.
Ishii K Takizawa K Okabe T Yamaguchi T Sakuma I 《Journal of nutritional science and vitaminology》2005,51(5):349-354
For effective exercise therapy after waking up, we focused on the staple food in diet therapy, and compared rice and bread diets. The subjects were 10 healthy college male students. After fasting for 12 h or more from the previous day, the subjects had breakfast consisting of rice (protein, 6.3 g; fat, 0.9 g: CHO, 79.3 g; energy, 368 kcal) or bread (protein, 15.7 g; fat, 5.8 g; CHO, 79.2 g; and energy, 450 kcal) containing the same amount of carbohydrates and the same side dishes (protein, 7.0 g; fat, 9.5 g; CHO, 21.3 g; energy, 199 kcal) in the morning 30 min before the initiation of exercise on a bicycle ergometer at an intensity of about 50% VO2max for 60 min. Measurements of the heart rate and expired gas were initiated 15 min before the start of exercise and continued until 10 min after exercise. Blood was collected before the meal, immediately before and 15, 30, and 45 min after the initiation of exercise, and immediately, 15, and 30 min after its termination. After breakfast containing carbohydrates, decreases were observed in the levels of free fatty acid and noradrenalin. Blood insulin (mealxtime, p<0.05 ANOVA) and triglyceride (meal x time, p<0.01, ANOVA) changed at higher levels in the bread diet than in the rice diet. Blood triglyceride is a resource of fat synthesis/accumulation, and insulin promotes its action. Therefore, the bread diet may promote fat synthesis/accumulation compared with the rice diet. 相似文献
86.
PURPOSE: Urokinase-type plasminogen activator (uPA) has an important role in tumor progression through the degradation of extracellular matrix. In addition, uPA receptor (uPAR) and plasminogen activator inhibitors (PAIs), composed of PAI-1 and 2, are also known to affect such activities. Tumor associated macrophage (TAM) is an important regulator of tumor progression that is associated with the uPA system in various cancers. However, to our knowledge the clinical significance of PAI-2 and the relationship between the uPA system and TAM in human renal cell carcinoma (RCC) tissues have not been investigated. We investigated and clarified these issues. MATERIALS AND METHODS: The subjects of the current study were 106 consecutive surgically resected specimens from patients with RCC. The expression of uPA, uPAR, PAI-1 and PAI-2 was determined by immunohistochemistry. We also examined the relationships among these molecules, survival and TAM. RESULTS: The mean immunoreactive scores (range 0 to 6) of uPA, uPAR, PAI-1 and PAI-2 were 3.09, 2.22, 1.99 and 0.56, respectively. These scores correlated with the grade and presence of metastasis. The expression of uPA, uPAR and PAI-1 but not PAI-2 correlated negatively with cause specific survival. Of uPA family members multivariate analysis showed that PAI-1 independently influenced cause specific survival. TAM counts correlated with PAI-1 only (p <0.001). CONCLUSIONS: Our results suggest that PAI-1 is an important regulator of tumor progression and survival, and PAI-1 may modulate them via TAM. On the other hand, PAI-2 has a minimum role in survival. Our results may help discussions of treatment strategy in patients with RCC. 相似文献
87.
Tubulin is the major constituent protein of microtubules. In mammals, there are seven beta-tubulins and six alpha-tubulins. Each beta-tubulin isotype has a unique tissue distribution. The purpose of this study was to describe the distribution of tubulin beta II in normal and neoplastic human tissues with immunohistochemical techniques. We obtained normal tissues from 33 cases (8 fetuses, 17 neonates, 3 children and 5 adults) and 121 samples of neoplastic tissue from surgical specimens or at autopsy. Immunohistochemical staining for tubulin beta II was performed using a monoclonal antibody, KNY379 developed in our laboratory. Tubulin beta II was detected in various normal tissues, particularly in fetal and neonatal tissues, such as the nervous system, pulmonary alveoli, bronchioles and bronchi, colon, pancreatic ducts and acini, renal convoluted tubuli, skin epidermis, body cavity mesothelial cells, smooth muscle and thymus. In the adult, broad expression was also observed; however, the immunoreactivity was weaker and the extent of its distribution decreased with age. In neoplastic tissues, tubulin beta II immunoreactivity was detected in various nervous system neoplasms and other neoplasms such as pancreatic solid cystic carcinoma, pleomorphic adenoma, Warthin's tumor, nephroblastoma, basal cell carcinoma and malignant mesothelioma. We conclude that our monoclonal antibody, KNY379, may be useful as a marker of nervous system neoplasm, pancreatic solid cystic carcinoma, pleomorphic adenoma, Warthin's tumor, nephroblastoma, basal cell carcinoma and malignant mesothelioma. 相似文献
88.
Itabashi Y Miyoshi S Kawaguchi H Yuasa S Tanimoto K Furuta A Shimizu T Okano T Fukuda K Ogawa S 《Artificial organs》2005,29(2):95-103
We developed a novel simple method for making functional myocardial cell sheets that may be used as transplants. Polymerized human fibrin-coated dishes were prepared with fibrinogen monomers mixed with thrombin. Neonatal rat cardiomyocytes cultured on these dishes formed myocardial cell sheets within 4 days. These cell sheets were easily dissociated intact from the polymerized fibrin layer, because the fibrin had been digested by intrinsic protease. Two overlaid myocardial cell sheets exhibited synchronized spontaneous beating and captured artificial pacing. Optical mapping confirmed that the conduction of the action potential between two partially overlaid myocardial cell sheets was established, and the action potential propagated across the junction without any delay. Transplanted three-layered myocardial cell sheets exhibited strong spontaneous beating and showed well-differentiated striations and an increase in cell size. This simple method of cell sheet engineering may also be applicable for various other cell types. 相似文献
89.
Hiraoka A Horiike N Akbar SM Michitaka K Matsuyama T Onji M 《Pathology, research and practice》2005,201(5):379-384
CD163 is a marker of activated macrophages, and increased levels of soluble CD163 have been detected in sera obtained from patients with hepatitis. The aim of this study was to detect the expression of CD163 in the liver from patients with viral hepatitis. Frozen sections of liver specimens were obtained from 5 patients with acute viral hepatitis (AH) and from 23 patients with chronic viral hepatitis (CH). The expression of CD163 in the liver was determined immunohistochemically using monoclonal antibody to human CD163. Double immunostaining was done to assess those cell types that express CD163 in the liver. The frequencies of CD163-positive cells were significantly higher both in the portal areas and in the hepatic lobules in the liver of patients with AH compared to those with CH (p < 0.05). Double immunostaining revealed that most of the CD163-positive cells were macrophages and Kupffer cells, because they expressed CD68. The expression of CD163 was very low in endothelial cells and liver stellate cells. This study shows that macrophages are activated in hepatitis liver. 相似文献
90.