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Aim: Because the procedure of balloon-occluded retrograde transvenous obliteration (B-RTO) causes extensive thrombosis of the major shunt that connects the spleen and gastric/renal venous systems, an increase in portal pressure is unavoidable. The aim of the present study was to assess the long-term outcome of B-RTO, including changes in esophageal varices. Methods: B-RTO was conducted in 22 patients with gastric varices, who were divided according to the severity of esophageal varices at baseline; there were no esophageal varices (n = 7), F(1) varices (n = 11), and F(2) varices (n = 4). The outcome measures included the development/worsening of esophageal varices after B-RTO and survival rates. Results: The cumulative bleeding-free probability for all 22 patients at 3 years after B-RTO was 100%. The overall 3-year survival was 94.4%. Seven patients who had no esophageal varices prior to B-RTO did not develop any after the procedure. Seven (63.6%) of the 11 patients with stage F(1) esophageal varices prior to B-RTO showed no changes in the varices after B-RTO, while two patients progressed to F(2) varices and two developed F(3) varices. The cumulative treatment-free probability of the esophageal varices at 24 months after B-RTO was 100% for patients without esophageal varices at baseline, 80.8% for patients with pre-existing F(1) varices, and 75% for those with pre-existing F(2) varices. Conclusion: Although the B-RTO procedure is considered useful for the treatment of gastric varices, changes in hemodynamics due to obliteration of this major shunt must be taken into account and observed closely.  相似文献   
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We investigated the role of an endogenousvasoconstrictor peptide endothelin-1 (ET-1) and freeradicals in local gastric ischemia-reperfusion injury inrats. Local gastric ischemia was induced by clamping the left gastric artery for 15 min andreperfusion was done for 10-30 min in the presence of150 mM exogenous HCl intragastrically. Local gastricischemia and reperfusion resulted in significantmacroscopic and microscopic gastric mucosal damage togetherwith elevation of gastric tissue ET-1 concentration.Gastric tissue ET-1 was found to increase after 15 minof ischemia alone and also with 30 min of reperfusion. A novel nonpeptide endothelin receptorantagonist, bosentan, or a combination of radicalscavengers (superoxide dismutase, catalase, anddeferoxamine) both attenuated gastric mucosal injury.However, the greater protection observed with bosentan thanwith radical scavengers might reflect a preferentialrole of endothelin-1 in this type of injury.  相似文献   
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Background: Iodine-123 metaiodobenzylguanidine (123I-MIBG) concentrates in adrenergic neurons and has been developed for evaluation of the sympathetic nervous system. Recent studies have demonstrated that the normal heart is clearly visualized by 123I-MIBG cardiac scintigraphy, whereas abnormal 123I-MIBG myocardial uptake and washout have been demonstrated in patients after myocardial infarction and in patients with congestive cardiomyopathy, long QT syndrome, and ventricular tachycardia. Hypothesis: Based on evidence from recent studies, it can be hypothesized that 123I-MIBG uptake is related to histopathologic changes in the myocardium. Methods: The relation of 123I-MIBG uptake to the histologic findings for the heart was studied in 24 patients with dilated cardiomyopathy (DCM). The study group did not include patients with complicating disorders that primarily affect the adrenergic nervous system. The 123I-MIBG uptake was visually assigned one of four grades using the two criteria of the mean score for six regional uptake grades (mean score) and the global score obtained by visual evaluation of the entire image (global score). The 123I-MIBG uptake score was also determined for the region at which the biopsy specimen was obtained (biopsy region score). The histologic findings were evaluated by assigning one of four grades for each of the following five factors: myocyte hypertrophy, myocardial fibrotic change, myocyte degeneration and necrosis, mononuclear cell infiltration, and myocyte disarray. The sum for all grades was defined as the total score, and the global score was also assigned to the overall histologic findings. Results: All of the global, mean, and biopsy region scores for 123I-MIBG uptake correlated significantly with the global and total scores for the histologic findings. Among the histologic factors, myocyte degeneration showed score correlated with all global, mean, and biopsy region scores for the uptake. Myocyte hypertrophy was associated weakly with the 123I-MIBG uptake scores. Conclusion: These results indicate that 123I-MIBG uptake imaging is associated with histopathologic abnormalities in patients with DCM.  相似文献   
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BackgroundEnhanced oxidative stress or defective anti-oxidant defenses are related to the pathogenesis of depressive symptoms. Lycopene is the most powerful antioxidant amongst the carotenoids. The aim of this study was to investigate the relationship between different vegetables, including tomatoes/tomato products (a major source of lycopene), and depressive symptoms in a community-based elderly population.MethodsWe analyzed a cross-sectional survey including 986 community-dwelling elderly Japanese individuals aged 70 years and older. Dietary intake was assessed using a valid self-administered diet-history questionnaire, and depressive symptoms were evaluated using the 30-item Geriatric Depression Scale with 2 cut-off points: 11 (mild and severe) and 14 (severe) or use of anti-depressive agents.ResultsThe prevalence of mild and severe and severe depressive symptoms was 34.9% and 20.2%, respectively. After adjustments for potentially confounding factors, the odds ratios of having mild and severe depressive symptoms by increasing levels of tomatoes/tomato products were 1.00, 0.54, and 0.48 (p for trend <0.01). Similar relationships were also observed in the case of severe depressive symptoms. In contrast, no relationship was observed between intake of other kinds of vegetables and depressive symptoms.LimitationsThis is a cross-sectional study, and not for making a clinical diagnosis of depressive episodes.ConclusionsThis study demonstrated that a tomato-rich diet is independently related to lower prevalence of depressive symptoms. These results suggest that a tomato-rich diet may have a beneficial effect on the prevention of depressive symptoms. Further studies are needed to confirm these findings.  相似文献   
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Purpose:To evaluate the feasibility for the detection of slight contrast effects after intravenous administration of single dose gadolinium-based contrast agent (IV-SD-GBCA), the time course of the GBCA distribution up to 24 h was examined in various fluid spaces and brain parenchyma using 3D-real IR imaging and MR fingerprinting (MRF).Methods:Twenty-four patients with a suspicion of endolymphatic hydrops were scanned at pre-administration and at 10 min, 4 and 24 h post-IV-SD-GBCA. 3D-real IR images and MRF at the level of the internal auditory canal were obtained. The signal intensity on the 3D-real IR image of the cerebrospinal fluid (CSF) in the cerebellopontine angle cistern (CPA), Sylvian fissure (Syl), lateral ventricle (LV), and cochlear perilymph (CPL) was measured. The T1 and T2 values of cerebellar gray (GM) and white matter (WM) were measured using MRF. Each averaged value at the various time points was compared using an analysis of variance.Results:The signal intensity on the 3D-real IR image in each CSF region peaked at 4 h, and was decreased significantly by 24 h (P < 0.05). All patients had a maximum signal intensity at 4 h in the CPA, and Syl. The mean CPL signal intensity peaked at 4 h and decreased significantly by 24 h (P < 0.05). All patients but two had a maximum signal intensity at 4 h. Regarding the T1 value in the cerebellar WM and GM, the T1 value at 10 min post-IV-GBCA was significantly decreased compared to the pre-contrast scan, but no significant difference was observed at the other time points. There was no significant change in T2 in the gray or white matter at any of the time points.Conclusion:Time course of GBCA after IV-SD-GBCA could be evaluated by 3D-real IR imaging in CSF spaces and in the brain by MRF.  相似文献   
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A 5-year-old girl presented with headache and vomiting. Head computed tomography and magnetic resonance imaging showed a right frontal lobe tumor with marked calcification. The patient underwent resection surgery with suspicion of anaplastic ependymoma, and the tumor was gross totally removed. Pathological examination revealed areas of dense tumor cells with a high nucleocytoplasmic ratio and myxoid areas consisting of tumor cells with a round-shaped nucleus and eosinophilic cytoplasm. Perivascular pseudorosette, necrosis, circumscribed growth, and microcalcification were also observed. Immunohistochemistry demonstrated negative staining for glial fibrillary protein and epithelial membrane antigen. Diagnosis of a high-grade neuroepithelial tumor (HGNET) with BCL6 corepressor (BCOR) alteration was made based on pathological findings and internal tandem duplication in the exon 15 of BCOR. Although calcification on radiological and pathological examination is not typical, it would be essential to recognize that calcification could appear in HGNET-BCOR.  相似文献   
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