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11.

Objectives

The aim of this study was to evaluate the apical sealability of Fillapex®, Endo-CPM-Sealer® and Sealapex®.

Material and Methods

Ninety-four freshly extracted single-rooted teeth were selected and decoronated. All teeth were radiographed to confirm the existence of a single and straight root canal, which was prepared using Protaper Universal and 2.5% sodium hypochlorite. The teeth were randomly divided in groups of 10 specimens each according to the sealer, and the canals were filled using the single cone technique and one of the sealers. Four additional teeth were used as controls. The teeth were submitted to dye leakage with Rhodamine B for 24 h but using vacuum on the initial 15 min. Thereafter, they were cut longitudinally and the leakage was measured in a linear fashion from apex to crown. Data were analyzed by ANOVA and Tukey''s tests at 5% significance level.

Results

Fillapex® and Sealapex® showed significantly less dye leakage than Endo-CPM-Sealer® (p<0.05).

Conclusions

It was concluded that Fillapex® and Sealapex® were able to prevent apical dye leakage differently from Endo-CPM-Sealer®.  相似文献   
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The purpose of this review is to understand the epidemiology, clinical features, etiopathogenesis, and management of atrioesophageal fistula (AEF) after atrial fibrillation (AF) ablation. The incidence of AEF after AF ablation is 0.015%-0.04%. The principal clinical features include fever, dysphagia, upper gastrointestinal bleeding, sepsis, and embolic strokes. The close proximity of the esophagus to the posterior left atrial wall is responsible for esophageal injury during ablation. Prophylactic proton pump inhibitors, esophageal temperature monitoring, visualization of the esophagus during catheter ablation, esophageal protection devices, and avoidance of energy delivery in close proximity to the esophagus play an important role in preventing esophageal injury. Early surgical repair or esophageal stenting are the mainstay of treatment. Eliminating esophageal injury during AF ablation is of utmost importance in preventing AEF. A high index of suspicion and early intervention is necessary to prevent fatal outcomes.  相似文献   
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Objective:To determine whether photos or silhouettes are adequate methods for evaluating the esthetic profiles of black subjects and whether black and white evaluators have different preferences for esthetic profiles.Materials and Methods:One photographic record of the profile of a black female patient with accentuated dental bimaxillary dentoalveolar protrusion was randomly selected. The image of the patient''s profile was altered to produce a series of seven photos and seven silhouettes (a total of 14 images) with different lip positions but uniform distances in relation to the esthetic plane created by Ricketts (line E). Fifty black and 50 white lay evaluators were invited to enumerate the photos and silhouettes, produced according to the lip position, in the order in which they considered most esthetically pleasing.Results:The number of preferences found to be within the esthetic norm was slightly higher among the photographs than among the silhouettes; the esthetic profile with a deviation of −2 mm from line E was elected as the most attractive, and the esthetic pattern with a deviation of +6 mm from the normal line E was considered the least attractive. There were no statistically significant differences between the preferences related to the variables race, sex, and educational background.Conclusions:The esthetic attractiveness of the facial profiles of black subjects in photos and silhouettes was evaluated in a similar manner among black and white evaluators. Among both black and white evaluators, the greatest preference was for the slightly concave profile, which was within the limit considered standard.  相似文献   
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Background:  Elevated levels of impulsivity and increased risk taking are thought to be core features of both bipolar disorder (BD) and addictive disorders. Given the high rates of comorbid alcohol abuse in BD, alcohol addiction may exacerbate impulsive behavior and risk-taking propensity in BD. Here we examine multiple dimensions of impulsivity and risk taking, using cognitive tasks and self-report measures, in BD patients with and without a history of alcohol abuse.
Methods:  Thirty-one BD subjects with a prior history of alcohol abuse or dependence (BD-A), 24 BD subjects with no history of alcohol abuse/dependence (BD-N), and 25 healthy control subjects (HC) were assessed with the Barratt Impulsiveness Scale (BIS) and the computerized Balloon Analogue Risk Task (BART).
Results:  Both BD groups scored significantly higher than controls on the BIS. In contrast, only the BD-A group showed impaired performance on the BART. BD-A subjects popped significantly more balloons than the BD-N and HC groups. In addition, subjects in the BD-A group failed to adjust their performance after popping balloons. Severity of mood symptomatology was not associated with performance on either task.
Discussion:  The current study supports a primary role of prior alcohol abuse in risk-taking propensity among patients with bipolar disorder. In addition, findings suggest that impulsivity and risky behavior, as operationalized by self-report and experimental cognitive probes, respectively, are separable constructs that tap distinct aspects of the bipolar phenotype.  相似文献   
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Lepromatous macrophages possess a regulatory phenotype that contributes to the immunosuppression observed in leprosy. CD163, a scavenger receptor that recognizes hemoglobin–haptoglobin complexes, is expressed at higher levels in lepromatous cells, although its functional role in leprosy is not yet established. We herein demonstrate that human lepromatous lesions are microenvironments rich in IDO+CD163+. Cells isolated from these lesions were CD68+IDO+CD163+ while higher levels of sCD163 in lepromatous sera positively correlated with IL‐10 levels and IDO activity. Different Myco‐bacterium leprae (ML) concentrations in healthy monocytes likewise revealed a positive correlation between increased concentrations of the mycobacteria and IDO, CD209, and CD163 expression. The regulatory phenotype in ML‐stimulated monocytes was accompanied by increased TNF, IL‐10, and TGF‐β levels whereas IL‐10 blockade reduced ML‐induced CD163 expression. The CD163 blockade reduced ML uptake in human monocytes. ML uptake was higher in HEK293 cells transfected with the cDNA for CD163 than in untransfected cells. Simultaneously, increased CD163 expression in lepromatous cells seemed to be dependent on ML uptake, and contributed to augmented iron storage in lepromatous macrophages. Altogether, these results suggest that ML‐induced CD163 expression modulates the host cell phenotype to create a favorable environment for myco‐bacterial entry and survival.  相似文献   
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Skin biopsy samples from 145 relapse leprosy cases and from five different regions in Brazil were submitted for sequence analysis of part of the genes associated with Mycobacterium leprae drug resistance. Single nucleotide polymorphisms (SNPs) in these genes were observed in M. leprae from 4 out of 92 cases with positive amplification (4.3%) and included a case with a mutation in rpoB only, another sample with SNPs in both folP1 and rpoB, and two cases showing mutations in folP1, rpoB, and gyrA, suggesting the existence of multidrug resistance (MDR). The nature of the mutations was as reported in earlier studies, being CCC to CGC in codon 55 in folP (Pro to Arg), while in the case of rpoB, all mutations occurred at codon 531, with two being a transition of TCG to ATG (Ser to Met), one TCG to TTC (Ser to Phe), and one TCG to TTG (Ser to Leu). The two cases with mutations in gyrA changed from GCA to GTA (Ala to Val) in codon 91. The median time from cure to relapse diagnosis was 9.45 years but was significantly shorter in patients with mutations (3.26 years; P = 0.0038). More than 70% of the relapses were multibacillary, including three of the mutation-carrying cases; one MDR relapse patient was paucibacillary.  相似文献   
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