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Background
Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients’ lives, as well as the need for and efficacy of endoscopic revision, are unclear.Aim
This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients’ lives and the need for endoscopic revision.Methods
This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients’ death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency.Results
Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43–198.98; P = 0.025).Conclusions
Endoscopic bilio-duodenal bypass is clinically effective, and the majority of the patients need no additional intervention until their death. Endoscopic revision is feasible and has a high success rate. 相似文献Background
We evaluated the impact of hypertension on the left ventricular mass regression in aortic stenosis after aortic valve replacement.Methods
We prospectively studied 135 patients with severe aortic stenosis at baseline and 1 year after surgery. In 32 patients we analyzed myocardial gene expression of collagen types I and III, connective tissue growth factor, transforming growth factor-β1, metalloproteinase-2 and its tissue inhibitor and compared its levels vs controls.Results
Seventy-six patients (56.3%) had a history of hypertension. Hypertensive patients were older, had higher Euroscore-II and NYHA class, with no differences in stenosis severity. At 1 year follow-up there was a median decrease of mass index of 14.2% (P25–75: − 4.3%–30.4%; p < 0.001). Mass regression was significantly higher in patients without hypertension, with a median decrease of 25.9% (P25–75: 12.0%–38.7%) vs 5.4% (P25–75: − 12.5%–20.1%; p = 0.001), despite similar increase in effective orifice area and no differences in valvuloarterial impedance. After 1 year, higher baseline left ventricular mass index (p = 0.005) and the absence of hypertension (p = 0.002) or diabetes (p = 0.041) were the only independent predictors of mass regression higher than the median. Comparing with controls, aortic stenosis patients had an increased expression of collagen types I and III, but only hypertensive patients had higher relative expression of collagen type I vs III. In hypertensive patients TIMP2 expression was up-regulated and correlated with higher baseline left ventricular mass index (r = 0.61; p = 0.020).Conclusions
In aortic stenosis, hypertension impairs mass regression one year after valve replacement, independently of total afterload. Differences in the expression of extracellular matrix remodeling genes might contribute to this finding. 相似文献To evaluate the potential of conventional glass ionomer cement (GIC), Biodentine™, MTA, and Portland cement to induce mineral density changes in carious dentin compared to zinc oxide eugenol control cement (ZOE).
Materials and methodsFifty blocks of bovine root dentin were prepared and a biofilm model using ATCC strains of S.mutans, S.sobrinus, and L.casei was used to promote artificial dentin lesions. After demineralization, the blocks were randomly divided into the five cement groups. Half of the surface of each specimen received the tested material and the other half was covered with wax (control). Samples were stored in phosphate buffered saline solution for 30 days and after that were scanned in a micro-CT with standardized parameters. Dentin mineral density changes were calculated using differences in plot profiles of the exposed and control carious dentin. Friedman’s test, followed by Wilcoxon signed-rank test was used with 5% significance.
ResultsMean ΔZ values for the cements were 48.63 ± 19.09 for the control (ZOE), 63.31 ± 32.59 for Biodentine™, 114.63 ± 72.92 for GIC, 109.56 ± 66.28 for MTA, and 106.88 ± 66.02 for Portland cement. All cements showed a statistically significant increase in ΔZ values compared to the control, but Biodentine™ values were statistically significantly lower compared to GIC and the other calcium silicate cements.
ConclusionsTested materials present potential to induce mineral density changes in carious bovine dentin. MTA, Portland, and GIC showed higher bioactivity potential than Biodentine™.
Clinical relevanceBased on minimally invasive concept, materials with remineralization potential can be used to preserve diseased but still repairable dental tissue.
相似文献