Enamel loss and adhesive remnants following bracket removal and various clean-up procedures in vitro

This study evaluated the enamel loss and composite remnants after debonding and clean-up. The tested null hypothesis is that there are no differences between different polishing systems regarding removing composite remnants without damaging the tooth surface. Brackets were bonded to 75 extracted human molars and removed after a storage period of 100 hours. The adhesive remnant index (ARI) was evaluated. The clean-up was carried out with five different procedures: 1. carbide bur; 2. carbide bur and Brownie and Greenie silicone polishers; 3. carbide bur and Astropol polishers; 4. carbide bur and Renew polishers; and 5. carbide bur, Brownie, Greenie and PoGo polishers. Silicone impressions were made at baseline (T0) and after debonding (T1) and polishing (T2) to produce plaster replicas. The replicas were analysed with a three-dimensional laser scanner and measured with analytical software. Statistical analysis was performed with the Kruskal-Wallis test and pairwise Wilcoxon tests with Bonferroni-Holm adjustment (α = 0.05). Enamel breakouts after debonding were detectable in 27 per cent of all cases, with a mean volume loss of 0.02 mm(3) (±0.03 mm(3)) and depth of 44.9 μm (±48.3 μm). The overall ARI scores was 3 with a few scores of 1 and 2. The composite remnants after debonding had a mean volume of 2.48 mm(3) (±0.92 mm(3)). Mean volume loss due to polishing was 0.05 mm(3) (±0.26 mm(3)) and the composite remnants had a mean volume of 0.22 mm(3) (±0.32 mm(3)). There were no statistically significant differences in volumetric changes after polishing (P?=?0.054) between the different clean-up methods. However, sufficient clean-up without enamel loss was difficult to achieve.     

COVID-19-related severe MS exacerbation with life-threatening Takotsubo cardiomyopathy in a previously stable patient and interference of MS therapy with long-term immunity against SARS-CoV-2

Journal of Neurology -     

How does susceptibility prevalence impact on the performance of disk diffusion susceptibility testing?

Antimicrobial disk diffusion susceptibility testing, devoted in a clinical context to predicting whether an antibiotic regimen will be effective, should be evaluated through predictive values. This approach implies that the susceptibility prevalence (frequency of susceptible, intermediate, and resistant isolates) affects the predictive value of a result. We quantified the influence of the susceptibility prevalence variation on the disk diffusion method performance through a modeling approach. Simulations based on a resampling procedure from two distinct minimum inhibitory concentration/diameter data sets were performed. Experimental variability on minimum inhibitory concentration and diameters was taken into account in the simulations. Results show that the susceptibility prevalence impact depends on the antibiotic and may be significant when prevalence variation is high enough. Consequences of these results on zone diameter breakpoint determination policy are discussed. This implies that the following should be done: (i) consider more rigorously the susceptibility prevalence in studies dealing with zone diameter breakpoint determination and performance evaluation, (ii) re-evaluate disk diffusion breakpoint consistency when the weight of prevalence variation is noteworthy, (iii) estimate consequences of a breakpoint international consensus on prediction quality and appropriate patient management.     

MCS-18, a novel natural product isolated from Helleborus purpurascens, inhibits dendritic cell activation and prevents autoimmunity as shown in vivo using the EAE model

Here we report for the first time that MCS-18, a novel natural product isolated from Helleborus purpurascens, is able to inhibit the expression of typical molecules of mature dendritic cells (DC) such as CD80, CD86, and especially of CD83 subsequently leading to a clear and dose-dependent inhibition of the DC-mediated T-cell stimulation. Furthermore, MCS-18 impeded the formation of the typical DC/T-cell clusters, which are essential to induce potent immune responses. Interestingly, MCS-18 also inhibited CCR7 expression on DC which subsequently lead to a dose-dependent block of the CCL19-mediated DC migration. MCS-18 not only inhibited the DC-mediated T-cell stimulation but also the anti-CD3/anti-CD28-mediated T-cell stimulation. Strikingly, MCS-18 also strongly reduced the paralysis associated with the experimental autoimmune encephalomyelitis (EAE), which is a murine model for human multiple sclerosis, in a prophylactic as well as in a "real" therapeutic setting. Even when the EAE was induced for a second time, the MCS-18-treated animals were still protected, suggesting that MCS-18 induces a long-lasting suppressive effect. In addition, and very important for the potential practical application in humans, MCS-18 was also active when administered orally. MCS-18 treatment almost completely reduced leukocyte infiltration in the brain and in the spinal cord. In conclusion, using in vitro as well in vivo assays we were able to show that MCS-18 exerts a strong immunosuppressive activity with remarkable potential for the therapy of diseases characterized by a pathologically over-activated immune system.     

Nasal Staphylococcus aureus carriage is not a risk factor for lower-airway infection in young cystic fibrosis patients

Staphylococcus aureus is one of the first pathogens which often persistently infect the airways of cystic fibrosis (CF) patients. Nasal S. aureus carriage is a risk factor for S. aureus infections in non-CF patients. Topical treatment strategies successfully eradicate nasal S. aureus carriage, thereby decreasing S. aureus infection. A prospective longitudinal multicenter study was conducted to assess whether nasal carriage represents a risk factor for S. aureus colonization of the oropharynx in young CF patients. Cross-sectional analysis revealed a significantly higher prevalence of S. aureus-positive nasal (28/80 [35%] versus 20/109 [18%]; P < 0.01) and oropharyngeal (35/80 [44%] versus 20/109 [18%]; P < 0.001) cultures in children with CF compared to a control group. The first site of S. aureus detection was the nose in 6 patients and the oropharynx in 14 patients, respectively. Longitudinal analysis demonstrated a significantly higher S. aureus prevalence (61/62 [98%] versus 47/62 [76%]; P < 0.001) and persistence (46/62 [74%] versus 31/62 [50%]; P < 0.01) in the oropharynx than in the nose. In CF patients, the oropharynx, and not the nose, was the predominant site of S. aureus infection and persistence. Hence, it is unlikely that CF patients will benefit from topical treatment strategies to eradicate nasal carriage.     

Significant genetic and antigenic variability within the env gene of systemic human immunodeficiency virus type 1 group O populations during the natural course of a heterosexual infection: a pilot study

We assessed the genetic and the antigenic variability within the env gene of peripheral blood human immunodeficiency virus (HIV) type 1 (HIV-1) group O populations during the natural course of a female heterosexual infection. Our data revealed the existence of a significant increase in amino acid sequence variability within the C2-V3 and gp41 regions (P = 0.023 and P < 0.001, respectively) in association with substitutions within neutralizing epitope sequences usually selected for HIV serological assays. These antigenic variations might significantly decrease the sensitivity of classical HIV enzyme-linked immunosorbent assays with blood samples of subjects heterosexually infected by HIV-1 group O strains. These findings may be of significant use both to devise diagnostic tools and to pursue suitable therapeutic modalities in cases of heterosexual infection by outlier HIV-1 strains.     

Prevalence,characteristics and risk factors of pressure ulcers in public and private hospitals care units and nursing homes in France

Objective: The aim of this study conducted in 2014 was to describe the prevalence of pressure ulcers in different types of French hospital unit at the national level to compare them with data from the 1994 and 2004 study.

Methods: This cross-sectional study was conducted over a single day. All care units were invited to participate by drawing lots stratified by region in successive waves until 1,200 agreements were obtained. Lots were drawn for towns with more than 10,000 inhabitants. All public- and private-sector hospital facilities in each town drawn by lot were invited to participate in the survey.

Results: 776 hospital services throughout France took part and accommodated 21,538 patients: 12,752 women (59.2%) and 8,786 men (40.8%). Of these patients, 1,753 (8.1%; IC95% = 7.7; 8.5) had pressure ulcers. The pressure-ulcer rate was 7.8% (IC95% = [7.3; 8.3] (n = 997)) for hospitalized women and 8.6% (IC95% = [8.0; 9.2] (n = 756)) for men (p = 0.0381). The 8.1% level reported in 2014 therefore points to a reduction in pressure-ulcer prevalence; 8.6% in 1994 and 8.9% in 2004.

Conclusions: The actions performed daily by healthcare professionals to prevent pressure ulcers, supported by research and training programs, including those by PERSE, are having a real impact over time.     

Use of a case-mix approach to study the trends in the incidence of second primary cancers

Purpose

To analyze trends in second primary cancer (SPC) incidence by using a case-mix approach to standardize on first cancer site distribution.