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991.

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   
992.

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   
993.
In 2012, the United Nations estimated that globally, 34 million people were living with human immunodeficiency virus (HIV) infection at the end of 2011.  相似文献   
994.
For the first time, juvenile toxicity of inorganic arsenic (As) was investigated in male rats, focusing on reproductive effects. As is a metalloid naturally occurring in the environment, being the inorganic forms the most toxics. Contaminated drinking water and agricultural products are the main prospectors of intoxication for general population. In the present study, Wistar male rats (21 days old) were distributed into three groups (n = 10/group): control (received vehicle‐filtered drinking water), As1 (received AsNaO2 at 0.01 mg L?1) and As2 (received AsNaO2 at 10 mg L?1). The animals were euthanized on PND 53. Testicular damages increased in As1 and As2 compared to control (ie, presence of vacuolization, acidophilic cells, and epithelium degeneration). Testicular interstitium of As1 and As2 presented fluid's increase and intense inflammatory infiltration. In the epididymis there was reduction of sperm amount in the lumen, besides epithelium areas presenting cribriform aspect in As1 and As2, exfoliation of cells in the light (in As1) and vacuoles (in As2). In epididymis interstitium, inflammatory infiltrates were observed in initial segment of As1 and As2. AsNaO2 changed immunolabeling pattern for androgen receptor in epididymis of As2, although serum testosterone levels was statistically comparable to control. Mass spectrometry revealed higher As concentrations in testis and epididymis of As2 compared to As1 and Control. These results indicate compromise of spermatogenesis and epididymal histophysiology in AsNaO2‐treated animals, possibly impairing sperm quality and fertility in long‐term, even at low levels of exposure. Investigations about the reversibility of reproductive damages are necessary to better understand the mechanisms of As reproductive toxicity.  相似文献   
995.
Cocaine is the most commonly used illicit drug among patients presenting at hospital emergency departments and the most frequent cause of drug-related deaths reported by medical examiners. Various respiratory problems temporally associated with cocaine use have been reported. Acute and chronic uses also are responsible for lung complications, such as pulmonary edema, alveolar hemorrhage, pulmonary hypertension, organizing pneumonia, emphysema, barotrauma, infection, cancer, eosinophilic disease, and aspiration pneumonia. Although most imaging findings are nonspecific, they may raise suspicion of a cocaine-related etiology when considered together with patients’ profiles and medical histories. This literature review describes cocaine-induced diseases with pulmonary involvement, with an emphasis on high-resolution chest computed tomographic findings and patterns.  相似文献   
996.
Some evidences suggest the involvement of the central nervous system in patients infected with SARS-CoV-2. We aim to analyze possible associations between coronavirus disease 2019 (COVID-19) pandemic and spontaneous subarachnoid hemorrhage (SAH), in a comprehensive neurological center.We conducted a retrospective case series of 4 patients infected by COVID-19, who developed spontaneous SAH. Clinical data were extracted from electronic medical records.Between March 24, 2020, and May 22, 2020, 4 cases (3 females; 1 male) of SAH were identified in patients infected with SARS-CoV-2, in a comprehensive neurological center in Brazil. The median age was 55.25 years (range 36 -71). COVID-19-related pneumonia was severe in 3 out of 4 cases, and all patients required critical care support during hospitalization. The patients developed Fisher grade III and IV SAH. Digital subtraction angiography (DSA) was performed in 3 of the 4 patients. However, in only 1 case, an aneurysm was identified. Inflammatory blood tests were elevated in all cases, with an average D-dimer of 2336 μg/L and mean C-reactive protein (CRP) of 3835 mg/dl The outcome was poor in the majority of the patients, with 1 death (25%); 2 (50%) remained severely neurologically affected (mRS:4); and 1 (25%) had slight disability (mRS:2).This study shows a series of 4 rare cases of SHA associated with COVID-19. The possible mechanisms underlying the involvement of SARSCoV-2 and SHA is yet to be fully understood. Therefore, SHA should be included in severe neurological manifestations in patients infected by this virus.  相似文献   
997.
998.
This study investigated the potential of five miRNA candidates for cerebral toxoplasmosis/HIV co-infection (CT/HIV) biomarkers. miR-155-5p, miR-146a-5p, miR-21-5p, miR-125b-5p and miR-29c-3p were tested in 79 plasma divided into groups: 32 CT/HIV patients; 27 individuals with asymptomatic toxoplasmosis (AT); and 20 individuals seronegative for toxoplasmosis (NC). From each was collected peripheral blood/EDTA for laboratory diagnosis. Blood cells for DNA extractions (molecular diagnosis), plasma for RNA extractions (gene expression) and ELISA (serological diagnosis). miRNA expression was performed by qPCR, and values were expressed in Relative Quantification (RQ). Among the five miRNAs, miR-21-5p and miR-146a-5p were up-expressed in CT/HIV group when compared with AT and NC groups. RQ means for miR-21-5p and miR-146a-5p in CT/HIV group were 3.829 and 2.500, while in AT group, were 1.815 and 1.661, respectively. Differences between 3 groups were statistically significant (Kruskal-Wallis ANOVA test), as well as CT/HIV and AT groups (Mann-Whitney test). Plasma of CT/HIV and AT groups expressed similar levels of miR-29c-3p, miR-155-5p and miR-125b-5p. As NC group was different of CT/HIV and AT groups, differences between three groups were statistically significant (Kruskal-Wallis ANOVA test). No difference was shown between CT/HIV and AT groups (Mann-Whitney test). These results suggest the host miRNAs modulation by Toxoplasma gondii.  相似文献   
999.
Objectives

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 methods

Fifty 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.

Results

Mean 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.

Conclusions

Tested materials present potential to induce mineral density changes in carious bovine dentin. MTA, Portland, and GIC showed higher bioactivity potential than Biodentine™.

Clinical relevance

Based on minimally invasive concept, materials with remineralization potential can be used to preserve diseased but still repairable dental tissue.

  相似文献   
1000.
Clinical Oral Investigations - The goal of this study is to propose a standard protocol of experimental occlusal trauma to evaluate the inflammatory hyperalgesia induced by metallic crowns on...  相似文献   
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