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61.
We report a 54-year-old Japanese woman who developed liver tumors 102 months after hepatic resection for hepatocellular carcinoma (HCC) and percutaneous transluminal angioplasty (PTA) for membranous obstruction of the inferior vena cava (MOVC), which is one form of Budd-Chiari syndrome. In the present admission workup showed no evidence of co-infection with hepatitis B and C viruses. Dynamic computed tomography (CT) and magnetic resonance imaging showed an enhanced lesion, 1.5cm in diameter, in segment 3 of the liver, and no obstruction of the inferior vena cava after PTA. CT during both arterial portography and hepatic arteriography revealed another lesion, showing different hemodynamics, in segment 2. The patient therefore underwent hepatic resection, and the tumors were diagnosed histologically as HCC. The two tumors differed in their morphological features, one containing abundant fibrous stroma, whereas the other did not. The nontumorous liver tissue showed central zonal fibrosis, i.e., reversed lobulation, and partial expansion of nodule-like formations, indicating lack of progression since the situation seen at the initial hepatectomy. The presence of nontumorous liver tissue showing the above features suggests that, even after successful treatment for relief of congestion, patients who have had MOVC should be followed closely for as long as possible because of the risk of HCC recurrence. This is the first reported case of HCC recurrence after successful treatment of MOVC.  相似文献   
62.
We have previously demonstrated that stimulation of the angiotensin (Ang) II type 2 receptor in vascular smooth muscle cells caused bradykinin production by activating kininogenase in transgenic mice. The aim of this study was to determine whether overexpression of AT2 receptors in cardiomyocytes attenuates Ang II-induced cardiomyocyte hypertrophy or interstitial fibrosis through a kinin/nitric oxide (NO)-dependent mechanism in mice. Ang II (1.4 mg/kg per day) or vehicle was subcutaneously infused into transgenic mice and wild-type mice for 14 days. The amount of cardiac AT2 receptor relative to AT1 receptor in transgenic mice was 22% to 37%. Ang II caused similar elevations in systolic blood pressure (by approximately 45 mm Hg) in transgenic mice and wild-type mice. Myocyte hypertrophy assessed by an increase in myocyte cross-sectional area, left ventricular mass, and atrial natriuretic peptide mRNA levels were similar in transgenic and wild-type mice. Ang II induced prominent perivascular fibrosis of the intramuscular coronary arteries, the extent of which was significantly less in transgenic mice than in wild-type mice. Inhibition of perivascular fibrosis in transgenic mice was abolished by cotreatment with HOE140, a bradykinin B2 receptor antagonist, or L-NAME, an inhibitor of NO synthase. Cardiac kininogenase activity was markedly increased (approximately 2.6-fold, P<0.001) after Ang II infusion in transgenic mice but not in wild-type mice. Immunohistochemistry indicated that both bradykinin B2 receptors and endothelial NO synthase were expressed in the vascular endothelium, whereas only B2 receptors were present in fibroblasts. These results suggest that stimulation of AT2 receptors present in cardiomyocytes attenuates perivascular fibrosis by a kinin/NO-dependent mechanism. However, the effect on the development of cardiomyocyte hypertrophy was not detected in this experimental setting.  相似文献   
63.
BACKGROUND/AIMS: Intraductal papillary neoplasm of the bile duct (IPNB) represents a biliary papillary tumor mainly growing in the bile duct lumen resembling intraductal papillary mucin-producing neoplasm of the pancreas. However, its clinical spectrum and characteristics have not been fully evaluated. METHODOLOGY: To define the clinicopathologic characteristics and prognosis of IPNB patients, 6 cases of IPNB who underwent surgical resection are presented. RESULTS: Patients were 3 males and 3 females, aged between 47 and 79 years. Five patients had histories of hepatobiliary disease. Imagery showed cystic or diffuse dilatation of the bile ducts. Tumor markers were not valuable for diagnosis. All patients underwent hemihepatectomy with or without resection of the caudate lobe or extrahepatic bile duct. Examination showed polypoid tumors in 5 cases though 1 case had no evident tumor. Mucin was observed in 3 cases. Five cases were well-differentiated adenocarcinoma and 1 had poorly differentiated adenocarcinoma. Vascular invasion was rare and lymph node metastasis was not observed. In-situ spread of carcinoma was seen along biliary mucosa in 3 cases. Five cases survived without tumor relapse for long periods but 1 died of tumor recurrence at 31 months. CONCLUSIONS: Complete resection of IPNB based on accurate preoperative assessment of tumor extension provides a good prognosis.  相似文献   
64.
65.
Soluble Fas ligand and atherosclerosis in hypertensive patients   总被引:2,自引:0,他引:2  
BACKGROUND : The Fas-Fas ligand (FasL) system is involved in apoptosis in many types of cells. Recently, the expression of FasL on endothelial cells was reported. FasL is cleaved by a metalloproteinase and released in serum as soluble FasL (sFasL). Vasoactive substances, including metalloproteinase, are modulated by endothelial dysfunction. Advanced atherosclerosis and impaired endothelial function are seen in hypertensive patients. The inflammatory response has an important role in the development of atherosclerosis, whereas C-reactive protein (CRP) is associated with the presence and severity of atherosclerosis. OBJECTIVE : To measure the intima-media thickness of the common carotid artery and evaluate the relationship between atherosclerosis and serum sFasL concentrations in hypertensive patients. PATIENTS AND MAIN OUTCOME MEASURES : Forty-seven patients with hypertension participated in the study. The intima-media thickness of the common carotid artery was evaluated by ultrasound imaging. Serum concentrations of sFasL were measured by enzyme-linked immunosorbent assay. RESULTS : Intima-media thickness correlated positively with age (r = 0.362, P = 0.012) and sFasL concentrations (r =0.332, P = 0.022), and negatively with creatinine clearance (r = -0.399, P = 0.0055). A general linear model analysis with atherosclerotic risk factors and sFasL revealed that age, sFasL, high-density lipoprotein-cholesterol and systolic blood pressure were significantly associated with intima-media thickness. Furthermore, we demonstrated that serum sFasL is directly associated with CRP concentration (r = 0.316, P = 0.030). CONCLUSIONS : These results indicated that serum sFasL concentration is associated with atherosclerosis and inflammatory disease, in patients with hypertension.  相似文献   
66.
We describe a case of mucinous cystadenoma of the appendix with perityphlic granuloma. The patient developed a hard palpable mass in the right lower quadrant and barium enema inducted irregular bowel wall at the cecum. Based on a preoperative diagnosis of carcinoma of the appendix, we performed a laparotomy. On operation, we found a tumor mass in the region of the appendix; the mass adhered strongly to the retroperitoneum and cecum. Right hemicolectomy was carried out on a diagnosis of carcinoma of the appendix. Microscopic examination revealed mucinous cystadenoma of the appendix with perityphlic granuloma. Mucinous cystadenoma in the appendix is a rare tumor. In this patient, the tumor was accompanied by granuloma formation in adjacent tissues because of mucin expelled from the appendix. This case emphasizes that granuloma formation can make of difficult to differentiate mucinous cystadenoma in the appendix from cancer.  相似文献   
67.
A rare case of systemic vasculitis with second component of complement (C2) deficiency was documented in a patient who developed colonic ulcerations, jejunal edema and dilatation, cutaneous ulcers, peripheral neuropathy, and psychosis. Colonoscopy revealed typical features of ischemic colitis and radiological examination showed ischemic changes in the jejunum and ileum. Histopathological examination of the cutaneous biopsy revealed typical necrotizing vasculitis. It is very likely that multiorgan involvement, including ischemic changes of the intestine, developed secondary to vasculitis associated with C2 deficiency.  相似文献   
68.
X-ray radiotherapy activates tumor antigen-specific T-cell responses, and increases in the serum levels of high mobility group box 1 (HMGB1) induced by X-ray irradiation play a pivotal role in activating anti-tumor immunity. Here, we examined whether carbon-ion beams, as well as X-rays, can induce HMGB1 release from human cancer cell lines. The study examined five human cancer cell lines: TE2, KYSE70, A549, NCI-H460 and WiDr. The proportion of cells surviving X- or carbon-ion beam irradiation was assessed in a clonogenic assay. The D10, the dose at which 10% of cells survive, was calculated using a linear–quadratic model. HMGB1 levels in the culture supernatants were assessed by an ELISA. The D10 dose for X-rays in TE2, KYSE70, A549, NCI-H460 and WiDr cells was 2.1, 6.7, 8.0, 4.8 and 7.1 Gy, respectively, whereas that for carbon-ion beams was 0.9, 2.5, 2.7, 1.8 and 3.5 Gy, respectively. X-rays and carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of A549, NCI-H460 and WiDr cells at 72 h post-irradiation with a D10 dose. Furthermore, irradiation with X-rays or carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of all five cell lines at 96 h post-irradiation. There was no significant difference in the amount of HMGB1 induced by X-rays and carbon-ion beams at any time-point (except at 96 h for NCI-H460 cells); thus we conclude that comparable levels of HMGB1 were detected after irradiation with iso-survival doses of X-rays and carbon-ion beams.  相似文献   
69.
70.
The potent and selective phosphodiesterase 4 inhibitor ASP3258 is a novel therapeutic agent for asthma and chronic obstructive pulmonary disease (COPD). After a single oral administration to rats, ASP3258 is rapidly absorbed with a bioavailability of 106%. In situ absorption data indicated that ASP3258 is mainly absorbed in the small intestine. Tissue distribution data after oral administration of 14C‐ASP3258 showed rapid and extensive distribution to various tissues. Excluding the gastrointestinal tract, the tissues with the highest concentrations were liver, heart and plasma. Liquid chromatography‐nuclear magnetic resonance spectroscopy data revealed that O‐glucuronidation of the carboxylic acid moiety of ASP3258 (formation of an acyl glucuronide) plays a key role in metabolism. No indication was found that the acyl glucuronide reacted with proteins in plasma or tissues. When 14C‐ASP3258 was orally administered to intact rats, urinary and fecal excretion accounted for 1.3% and 100.6% of the administered radioactivity, respectively. After a single oral administration of 14C‐ASP3258 to bile‐cannulated rats, urinary and biliary excretion accounted for 0.7% and 93.8% of the administered radioactivity, respectively. These findings suggest that fecal excretion via bile plays an important role in the elimination of ASP3258‐derived radioactivity. In vitro metabolic profiles were relatively similar among the species examined, suggesting that our findings in rats may help us to understand pharmacokinetics, efficacy and safety profiles in humans and other species. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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