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111.
Journal of Interventional Cardiac Electrophysiology - Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, occurring in 1–2% of the general population. Catheter ablation...  相似文献   
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OBJECTIVES: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads. BACKGROUND: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium. METHODS: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide. RESULTS: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS). CONCLUSIONS: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.  相似文献   
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BACKGROUND: In the absence of evidence-based data, the optimal antithrombotic treatment after coronary artery stenting in patients on chronic oral anticoagulation (OAC) remains unknown. In order to investigate current practice in this setting, an international survey was carried out. METHODS: A questionnaire was e-mailed to 40 internationally renowned, foreign Interventional Centers worldwide. RESULTS: Out of the 24 Centers (60%) replying, only in 13 (54%) is antithrombotic treatment carried out in accordance with a standardized protocol. OAC is stopped in favor of aspirin plus ticlopidine/clopidogrel in selected (low thromboembolic risk) conditions in 13 (54%) Centers. When OAC is continued, the association with a single antiplatelet is employed in a few Centers only, as opposed to triple antithrombotic treatment (OAC and aspirin plus ticlopidine/clopidogrel) which is adopted, selectively or systematically, in the majority (83%) of Centers. In 8 (33%) Centers adopting triple antithrombotic treatment, the dose of OAC is decreased in all patients, whereas in 9 (38%) it is left unchanged. Upon completion of 1 to 3-6 months of antithrombotic treatment with OAC and single/dual antiplatelets, in 9 (38%) Centers this regimen is continued indefinitely, whereas in 10 (41%) antiplatelets are systematically withdrawn. Out of the 13 Centers, selectively exchanging OAC for aspirin plus ticlopidine/clopidogrel, low- or full-dose low-molecular-weight heparin is added in selected (high thromboembolic risk) cases in 3 (23%) and 5 (38%) Centers, respectively. Following 1 to 3-6 months of aspirin plus ticlopidine/clopidogrel antithrombotic treatment, OAC is resumed in all cases in 9 (69%) Centers and in no cases in 1 (8%). CONCLUSIONS: Our survey shows a high variability in the current antithrombotic treatment of patients on chronic OAC undergoing coronary artery stenting. Although various regimens may be adopted, the optimal antithrombotic treatment for this patient subset still needs to be identified.  相似文献   
116.
La radiologia medica - This study aims to analyze safety and effectiveness of PHIL® (Microvention, CA-USA) in peripheral endovascular embolization procedures, both in elective and emergent...  相似文献   
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OBJECTIVES: The goal of this study was to test the hypothesis that NCX-4016 may have broader anti-inflammatory and antithrombotic effects as well as better gastric tolerability than aspirin in humans. BACKGROUND: NCX-4016 is an aspirin derivative containing a nitric oxide-releasing moiety that prevents platelet activation and modulates tissue factor (TF) expression and cytokine release from lipopolysaccharide (LPS)-stimulated monocytes. METHODS: This was a blind-observer, placebo-controlled, parallel-group study in which 48 healthy subjects were randomized to receive NCX-4016 800 mg twice a day, NCX-4016 800 mg twice a day plus aspirin 325 mg, aspirin 325 mg, or placebo for 21 days. RESULTS: Similar to aspirin alone, NCX-4016 effectively inhibited platelet aggregation induced by 0.6 mmol/ arachidonic acid, clot-stimulated thromboxane (TX) B2 generation in whole blood, and urinary excretion of 11-dehydro-TXB2. Unlike aspirin alone, the administration of NCX-4016 significantly inhibited TF expression in monocytes stimulated ex vivo with 10 micromol/l LPS (determined by flow-cytometry analysis of TF on CD14 positive cells). NCX-4016 also inhibited the rapid TF expression induced in monocytes by a proteinase activated receptor agonist (thrombin receptor activator protein, 2 micromol/l) as well as LPS-induced expression of CD11b . Ex vivo, release of MCP-1 and interleukin-6 were significantly inhibited by NCX-4016, but not by aspirin. NCX-4016 was not associated with gastric damage, and significantly reduced gastric injury when co-administered with aspirin, although both drugs reduced gastric PGE2 production to the same extent. CONCLUSIONS: NCX-4016 is equally effective as aspirin in inhibiting cyclooxygenase activity. However, NCX-4016 causes less gastric damage and prevents monocyte activation. Larger multicenter trials are warranted to establish clinical efficacy and safety of NCX-4016.  相似文献   
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Selective Alzheimer's disease indicator-1 (seladin-1) is a novel gene with antiapoptotic activity that is down-regulated in vulnerable brain regions in Alzheimer's disease. This gene encodes 3-beta-hydroxysterol Delta-24-reductase (DHCR24), which converts desmosterol into cholesterol. In the adrenal cortex, increased expression of seladin-1/DHCR24, which appears to be modulated by ACTH, has been recently reported in cortisol-secreting adenomas, compared with the adjacent atrophic tissue. In our study, we measured the expression level of seladin-1/DHCR24 in cortisol- (n = 18) and aldosterone-secreting (n = 16) adrenocortical adenomas, in carcinomas (n = 17), and in normal adrenal glands (n = 8) by quantitative real-time RT-PCR. The amount of seladin-1/DHCR24 mRNA was significantly reduced in carcinomas (total RNA, 2.5 +/- 0.8 pg/ micro g) compared with the other groups (P < 0.01). Western blot analysis confirmed the mRNA results. Similarly, in adrenal malignancies, significantly reduced levels of expression of the ACTH receptor gene were found. In the adrenal cancer cell line H295R and in primary cultures from adrenocortical cells, ACTH (1 nM) and forskolin (10 micro M) effectively increased seladin-1/DHCR24 expression, confirming that seladin-1/DHCR24 is modulated by the ACTH/cAMP-driven pathway. In summary, this is the first demonstration that seladin-1/DHCR24 expression is reduced in adrenal cancer, suggesting that it might be viewed as a new potential marker of adrenal malignancies.  相似文献   
119.
The most common primary lymphoma of the gastrointestinal tract is B-cell lymphoma arising from mucosa-associated lymphoid tissue known as MALT lymphoma. Although the majority of these lesions affect the stomach and are associated with Helicobacter pylori organisms, sites other than the gastrointestinal tract may be affected. This case report describes a patient with concomitant laryngeal MALT lymphoma and Helicobacter pylori-related gastric MALT lymphoma derived from the same clone as confirmed by PCR. Treatment of Helicobacter pylori infection in this patient using antibiotics led to regression of both lesions. This patient remains in remission at 46-month follow-up. This is the first case report on the regression of a laryngeal MALT lymphoma after Helicobacter pylori eradication. We suggest that all patients presenting with extragastric MALT lymphoma should undergo upper gastrointestinal endoscopy with gastric biopsies for the determination of Helicobacter pylori status and presence of concomitant gastric MALT lymphoma, followed by a course of anti-Helicobacter pylori antibiotic therapy. Nonresponders may subsequently be considered for surgery and/or chemo/radiation therapy.  相似文献   
120.
Our aim was to evaluate incidence and riskfactors of liver involvement in obese Italian childrenas assessed by both ultrasonographic and biochemicalparameters. In seventy-five consecutive obese children (age 9.5 ± 2.9 years, males/females41/34), serum levels of enzymes and ultrasonography ofthe liver were evaluated. Tests were repeated one,three, and six months after starting a moderatehypocaloric diet and an exercise program. Three obese childrenwho were found to have chronic viral hepatitis wereexcluded from the study. Thirty-eight of 72 (53%) obesechildren had an ultrasonographic image of bright liver consistent with liver steatosis. Thelatter was severe in nine children, moderate in 16, andmild in 13. Eighteen obese children (25%) had elevatedtransaminase levels. Bright liver andhypertransaminasemia were not due to any of the most common causesof liver disease. Both were rapidly responsive to lossof weight, confirming that liver involvement wassecondary to obesity and that steatosis orsteatohepatitis rather than fibrosis were involved. Obesityduration not more than three years (odds ratio = 4.77),a higher degree of obesity (odds ratio = 2.09), andhypertransaminasemia (odds ratio = 2.15) appeared asimportant predictive factors of liver involvement atultrasonography. Incidence of liver involvement assessedby means of ultrasonography is significantly higher thanthat revealed by measurement of serum liver enzymes. A short duration of obesity emerged as apotentially new risk factor of liver involvement in thepediatric obese population and needs to be confirmed infuture studies.  相似文献   
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