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ObjectivesThe aim of this in vitro study was to evaluate the effect of air-abrasion surface pre-treatment with bioactive glass (BAG) 45S5 on enamel surface loss after erosion/abrasion challenge.MethodsTwenty-four sound bovine incisors were used for this study. Four experimental groups (n = 12) were assigned as follows: Group 1 was the negative control group, Group 2 specimens were treated with a SnF2 gel (positive control group), Group 3 specimens were air-abraded with BAG 45S5 (ProSylc) and Group 4 received both treatments. The specimens were submitted to erosion/abrasion challenge using a common soft drink. Enamel surface loss was evaluated using an optical profilometer. Additionally, surface roughness (VSI method) and surface microhardness (Vickers method) changes were evaluated, as well as SEM and EDS analyses were performed on enamel surface. The data were statistically analyzed using one-way ANOVA and Tukey’s post-hoc test at a level of significance a = 0.05.ResultsSurface pre-treatment with BAG 45S5 reduced surface loss in comparison with negative control group (p < 0.001), which exhibited the highest surface loss of the experimental groups (p < 0.05). The positive control group (SnF2 treatment) and Group 4 specimens, which received both air-abrasion pre-treatment and SnF2 treatment, presented the lowest surface loss (p < 0.05), but did not show significant differences to each other (p = 0.65).SignificanceAir-abrasion pre-treatment with BAG 45S5 may be beneficial as an in-office preventive method for the limitation of enamel erosive wear induced by excessive consumption of soft drinks. The clinical significance of the results regarding this preventive method should be confirmed by clinical studies.  相似文献   
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Diastolic dysfunction refers to abnormal diastolic filling properties of the left ventricle regardless of whether systolic function is normal or the patient has symptoms. Diastolic heart failure (HF), or more accurately, HF with preserved systolic function, is a distinct clinical entity characterized by the presence of the triad of impaired diastolic function, normal systolic function (left ventricular ejection fraction > 50%), and symptoms of HF. Patients with HF with preserved systolic function are frequently symptomatic from both acute and chronic elevations in left ventricular end-diastolic pressure and/or left atrial pressure.  相似文献   
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Objectives

The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.

Background

There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.

Methods

Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.

Results

A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: ?8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.

Conclusions

Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927)  相似文献   
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Late onset neonatal sepsis (LOS) has a high mortality and the optimal management is poorly defined. We aimed to evaluate new expert panel-derived criteria to define LOS and characterize the current management and antibiotic susceptibility of LOS-causing organisms in Europe. A prospective observational study enrolled infants aged 4 to 90 days in five European countries. Clinical and laboratory findings as well as empiric treatment were recorded and patients were followed until the end of antibiotic therapy. Failure was defined as a change of primary antibiotic, no resolution of clinical signs, appearance of new signs/pathogens or death. Antibiotic therapy was considered appropriate if the organism was susceptible to at least one empiric antibiotic. 113 infants (median age 14 days, 62 % ≤1500 g) were recruited; 61 % were culture proven cases (28 CoNS, 24 Enterobacteriaceae, 11 other Gram-positives and 6 Gram-negative non-fermentative organisms). The predictive value of the expert-panel criteria to identify patients with a culture proven LOS was 61 % (95 % CI 52 % to 70 %). Around one third of Enterobacteriaceae were resistant to ampicillin + or cefotaxime + gentamicin but only 10 % to meropenem. Empiric treatment contained a total of 43 different antibiotic regimens. All-cause mortality was 8 % with an additional 45 % classified as failure of empiric therapy, mainly due to change of primary antibiotics (42/60). Conclusions: The expert panel—derived diagnostic criteria performed well identifying a high rate of culture proven sepsis. Current management of LOS in Europe is extremely variable suggesting an urgent need of evidence-based guidelines.  相似文献   
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