Conventional dual-cure versus self-adhesive resin cements in dentin bond integrity

During post preparation, the root canal is exposed to the oral cavity, and endodontic treatment may fail because of coronal leakage, bacterial infection and sealing inability of the luting cement. OBJECTIVE: this study quantified the interfacial continuity produced with conventional dual-cure and self-adhesive resin cements in the cervical (C), medium (M) and apical (A) thirds of the root. MATERIAL AND METHODS: Forty single-rooted human teeth were restored using Reforpost # 01 conical glass-fiber posts and different materials (N=10 per group): group AC=Adper&#8482; ScotchBond&#8482; Multi-purpose Plus + AllCem; group ARC=Adper&#8482; ScotchBond&#8482; Multi-purpose Plus + RelyX ARC; group U100=RelyX U100; and group MXC=Maxcem Elite. After being kept in 100% humidity at 37°C for 72 hours, the samples were sectioned parallel to their longitudinal axis and positive epoxy resin replicas were made. The scanning electron micrographs of each third section of the teeth were combined using Image Analyst software and measured with AutoCAD-2002. We obtained percentage values of the interfacial continuity. RESULTS: Interfacial continuity was similar in the apical, medium and cervical thirds of the roots within the groups (Friedman test, p>0.05). Comparison of the different cements in a same root third showed that interfacial continuity was lower in MXC (C=45.5%; M=48.5%; A=47.3%) than in AC (C=85.9%, M=81.8% and A=76.0%), ARC (C=83.8%, M=82.4% and A=75.0%) and U100 (C=84.1%, M=82.4% and A=77.3%) (Kruskal-Wallis test, p<0.05). CONCLUSIONS: Allcem, Rely X ARC and U100 provide the best cementation; cementation was similar among root portions; in practical terms, U100 is the best resin because it combines good cementation and easy application and none of the cements provides complete interfacial continuity

The N-Terminal Domain and Glycosomal Localization of Leishmania Initial Acyltransferase LmDAT Are Important for Lipophosphoglycan Synthesis

Ether glycerolipids of Leishmania major are important membrane components as well as building blocks of various virulence factors. In L. major, the first enzyme of the ether glycerolipid biosynthetic pathway, LmDAT, is an unusual, glycosomal dihydroxyacetonephosphate acyltransferase important for parasite's growth and survival during the stationary phase, synthesis of ether lipids, and virulence. The present work extends our knowledge of this important biosynthetic enzyme in parasite biology. Site-directed mutagenesis of LmDAT demonstrated that an active enzyme was critical for normal growth and survival during the stationary phase. Deletion analyses showed that the large N-terminal extension of this initial acyltransferase may be important for its stability or activity. Further, abrogation of the C-terminal glycosomal targeting signal sequence of LmDAT led to extraglycosomal localization, did not impair its enzymatic activity but affected synthesis of the ether glycerolipid-based virulence factor lipophosphoglycan. In addition, expression of this recombinant form of LmDAT in a null mutant of LmDAT did not restore normal growth and survival during the stationary phase. These results emphasize the importance of this enzyme's compartmentalization in the glycosome for the generation of lipophosphoglycan and parasite's biology

Short-term exposure to traffic-related air pollution and daily mortality in London, UK.

Epidemiological studies have linked daily concentrations of urban air pollution to mortality, but few have investigated specific traffic sources that can inform abatement policies. We assembled a database of >100 daily, measured and modelled pollutant concentrations characterizing air pollution in London between 2011 and 2012. Based on the analyses of temporal patterns and correlations between the metrics, knowledge of local emission sources and reference to the existing literature, we selected, a priori, markers of traffic pollution: oxides of nitrogen (general traffic); elemental and black carbon (EC/BC) (diesel exhaust); carbon monoxide (petrol exhaust); copper (tyre), zinc (brake) and aluminium (mineral dust). Poisson regression accounting for seasonality and meteorology was used to estimate the percentage change in risk of death associated with an interquartile increment of each pollutant. Associations were generally small with confidence intervals that spanned 0% and tended to be negative for cardiovascular mortality and positive for respiratory mortality. The strongest positive associations were for EC and BC adjusted for particle mass and respiratory mortality, 2.66% (95% confidence interval: 0.11, 5.28) and 2.72% (0.09, 5.42) per 0.8 and 1.0 μg/m(3), respectively. These associations were robust to adjustment for other traffic metrics and regional pollutants, suggesting a degree of specificity with respiratory mortality and diesel exhaust containing EC/BC

Does Hybridization of Intraradicular Dentin Really Improve Fiber Post Retention in Endodontically Treated Teeth?

This study tested the hypothesis that hybridization of intraradicular dentin eliminates interfacial gaps, thereby improving the coronal seal and retention of teeth restored with fiber posts. Post spaces were bonded with two types of fiber posts, using the corresponding etch-and-rinse adhesives and dual-cured resin cements. Longitudinal sections of the interfaces were examined for dentin hybridization in the coronal- and middle-thirds of the root canals. Resin replicas of these sections were evaluated for interfacial gap formation. Although intraradicular dentin hybridization was not compromised irrespective of whether the adhesives were light-cured before cementation, the universal occurrence of interfacial gaps along the hybrid layer surface or the post-cement interface reflects the challenge in bonding to post spaces with low compliance and high C-factors. The clinical success associated with bonded fiber posts is probably due predominantly to frictional retention

Contagious Caprine Pleuropneumonia

Contagious caprine pleuropneumonia (CCPP), caused by Mycoplasma capricolum subsp. capripneumoniae, is an OIE-listed disease affecting goats and wild ungulate species. CCPP is present in Africa, the Middle East, and Central Asia, but its exact distribution is unknown, particularly in Asia. It is enzootic in the Middle East and East Africa, while it has only been sporadically reported in North and Central Africa and, though suspected, has never been identified in West Africa. In addition, there are very few studies reporting the prevalence and losses induced by CCPP, which are greatly underestimated. This uncertainty over the distribution and impact of CCPP is partly due to the fastidious nature of its etiologic agent, which is difficult to identify, particularly when it circulates in an insidious, mild, or asymptomatic form, favored by the use of antibiotic treatments. However, specific molecular and serological tests are now available for the diagnosis of CCPP, even in the absence of isolation. The main limitation of CCPP surveillance remains the lack of awareness by veterinary services. Vaccines based on inactivated antigens in saponin can induce good protection and their variable quality may now be assessed using a specific ELISA. However, they are very expensive, and there is a paucity of vaccine producers to satisfy their demand. Efforts must urgently be directed to the development of cheaper, quality-controlled vaccines to be extensively used in the field. The global campaign to eradicate “peste des petits ruminants” by 2030 may be a great opportunity to target other goat diseases such as CCPP