Effect of immersion in distilled water or phosphate-buffered saline on the solubility, volumetric change and presence of voids within new calcium silicate-based root canal sealers.

AIM: To assess the effect of immersion in distilled water or phosphate-buffered saline (PBS) on the solubility, volumetric change and presence of voids of calcium silicate-based root canal sealers (TotalFill BC, Sealer Plus BC and Bio-C), in comparison with the gold standard epoxy resin-based sealer (AH Plus). METHODOLOGY: All properties were evaluated after immersion in distilled water or PBS. Solubility was determined by the percentage of mass loss, whereas volumetric change and presence of voids were evaluated by micro-computed tomography, after 7 days of immersion. The volumetric change and percentage of voids between the baseline (after setting) and the experimental period were calculated. Statistical analysis was performed using one-way anova and Tukey's or Student's t-tests (α = 0.05). RESULTS: The calcium silicate-based sealers had significantly greater solubility and volumetric loss than AH Plus, after immersion in distilled water or PBS (P < 0.05). Bio-C had the greatest solubility (P < 0.05), followed by TotalFill BC and Sealer Plus BC, which were similar (P > 0.05). Regarding the volumetric change, AH Plus had a volume increase, with similar values in distilled water and PBS (P > 0.05). TotalFill BC, Sealer Plus BC and Bio-C had a similar volumetric change (P > 0.05). The calcium silicate-based materials had the greatest solubility and volume loss after immersion in distilled water (P < 0.05). There was no difference in the percentage of voids amongst the sealers, before and after immersion in distilled water or PBS (P > 0.05). CONCLUSIONS: TotalFill BC, Sealer Plus BC and Bio-C had significantly greater solubility and volumetric loss than AH Plus. Although storage in PBS significantly reduced the solubility and volumetric change of calcium silicate-based sealers, their solubility remained above that recommend by ISO 6876. All the sealers evaluated had low and similar voids, even after immersion in distilled water or PBS.

Vitamin D levels and risk for periodontal disease: A systematic review.

OBJECTIVE: To evaluate the existing evidence supporting or refuting the following questions: (i) Do patients with lower vitamin D levels have higher risk for periodontal disease? (ii) Are periodontal treatment outcomes improved by the adjuvant supplementation of vitamin D or by elevated serum vitamin D levels? MATERIAL AND METHODS: MEDLINE, SCOPUS, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched up to September 2017. Studies were included if they had measured serum vitamin D levels or vitamin D intake and any periodontal parameter. RESULTS: Overall, 27 studies were included (13 cross-sectional studies, 6 case-control studies, 5 cohort studies, 2 randomized clinical trials and 1 case series study). Sixty-five percent of the cross-sectional studies reported significant associations between low vitamin D levels and poor periodontal parameters. None of the observational longitudinal studies found that periodontal disease progression could be attributed to lower vitamin D levels. No interventional studies that evaluated the use of vitamin D supplementation as a solely adjuvant to periodontal treatment was found. No meta-analysis was performed due to high variability across studies. CONCLUSION: The data to support or refute the association between vitamin D levels and periodontal disease are inconclusive at the moment. More rigorously designed longitudinal studies with standardized definitions of periodontal disease and vitamin D are necessary.

Relationship between oro and nasopharynx permeability and the direction of facial growth.

AIM: Most scientific literature relates vertical growth to individuals with decreased upper airway permeability. However, we often find subjects with a long face and a normal breathing pattern, most likely caused by other aetiological factors. And, frequently, we also find decreased upper airway permeability with horizontal growth. The aim of the study was to compare the cephalometric measurements of the oro and nasopharynx permeability with the facial growth direction and to identify the most common facial growth direction in individuals with decreased upper airway permeability. MATERIALS AND METHODS: Cephalometric analysis was carried out in 158 pre-adolescent patients at the Orthodontic appointment, using facial profile teleradiographs. Parameters used were Jabarak's ratio and measurement of oro-nasopharynx space. Data collected were submitted to statistical treatment. RESULTS: This study points to the presence of an intermediate growth in individuals with diminished oro and nasopharynx permeability, either simultaneous or separate. The number of individuals with diminished permeability and vertical growth is close to the number of individuals with horizontal growth. CONCLUSIONS: The individuals with diminished permeability of the upper airway present an intermediate growth direction, representing the most frequent type. In the less common growth directions, there is a slight tendency to horizontal facial growth verified in individuals with diminished nasopharynx permeability. Also, a light tendency to vertical facial growth is present when oropharynx permeability is reduced.

Electromyographic analysis of masseter and temporal muscles, bite force, masticatory efficiency in medicated individuals with schizophrenia and mood disorders compared with healthy controls.

This study aimed to comparatively analyse the electromyographic activity of the masseter and temporal muscles at rest and during mandible postural clinical conditions (right and left laterality, protrusion and maximum voluntary contraction), right and left maximum molar bite forces and the masticatory efficiency of individuals with schizophrenia or mood disorders - all medicated (medicated groups) compared with control group (healthy volunteers) via electromyography. Individuals were distributed into three groups: Group I (Schizophrenia - 20 individuals), Group II (mood disorders - 20 individuals) and Group III (Control - 40 individuals). Basically, the results were only statistically significant for the clinical mandible conditions and bite force. The most unsatisfactory results were observed in the medicated groups in relation to the control group. The group with mood disorders obtained the most unsatisfactory results compared with the group with schizophrenia. It was suggested by these observations that the association of mood disorders and schizophrenia with medication has negatively affected the stomatognathic system in relation to controls when the electromyography and bite force were used for the analysis.

Numerical simulation of in-vitro dispersion and deposition of nanoparticles in dry-powder-inhaler aerosols.

Aerosol dispersion and deposition inside an idealized mouth-throat has been numerically simulated using a stochastic Lagrangian model accounting for Brownian motion and particle-wall interaction. Delivery of nanoparticles to the lungs is extremely difficult, mainly due to their low inertia, and for this reason they are often loaded into larger carrier particles. Bearing in mind the potentialities of nanoparticles in advanced drug delivery, a set of monodisperse particles with diameters in the nanqsize range, as well as in the respirable and carrier ranges, were considered in the present simulations. Deposition patterns were obtained by tracking a total of 16,000 particles for each diameter. The results have shown that similar patterns were obtained in the mouth-throat for 400 nm particles and larger. A clear correspondence between secondary flow structures in the fluid and these deposition patterns was observed, demonstrating the role of the convective transport processes for this size range. In contrast, a much more uniform distribution of the particles adhering to the walls was noted for a size of 200 nm. It was also found that a very large amount of these particles (nearly 80%) is lost by deposition on the mouth-throat, thus recommending the use of larger carrier particles.

Ellis-van Creveld Syndrome (chondro-ectodermal dysplasia) in two siblings.

Two male siblings aged 12 and 15 years (Figure 1) presented with growth retardation, limb abnormalities and, defective teeth and nail since childhood. There was no history of similar defects in other family members. On examination their height was 114 cm and 130 cm (expected height; 169 cm and 150 cm) respectively. There were hypoplastic and dystrophic nails, and microdontia and hypodontia on dental examination. There were post-axial polydactyly in both the hands and left foot. Skeletal survey revealed short forearms, legs & distal phalanges (Acromesomelia). Cardiac or other organ system defects were not noticed on clinical examination or echocardiogram. Clinical picture was suggestive of a diagnosis of Chondroectodermal dysplasia (Ellis van Creveld syndrome). These cases have been reported for their rarity and for the presence of some rare features of this syndrome.

Review of the Global Distribution of Foot-and-Mouth Disease Virus from 2007 to 2014.

Foot-and-mouth disease (FMD) virus affects livestock worldwide. There are seven different serotypes, each with a diversity of topotypes, genetic lineages and strains. Some lineages have different properties that may contribute to sporadic spread beyond their recognized endemic areas. The objective of this study was to review the most significant FMD epidemiological events that took place worldwide between 2007 and 2014. Severe epidemics were caused by FMD virus (FMDV) lineage O/Asia/Mya-98 in Japan and South Korea in 2010, both previously free of disease. In India, where FMD is endemic, the most important event was the re-emergence of lineage O/ME-SA/Ind-2001 in 2008. Notably, this lineage, normally restricted to India, Bangladesh, Nepal and Bhutan, was also found in Saudi Arabia and Libya in 2013 and has caused several outbreaks in Tunisia and Algeria in 2014-2015. In January 2011, FMDV-positive wild boars were found in Bulgaria, where the disease last occurred in 1996, followed by 12 outbreaks in livestock infected with FMDV O/ME-SA/PanAsia2. In 2012, FMDV SAT2 caused outbreaks in Egypt and the Palestinian Autonomous Territories. Another significant event was the emergence of FMDV Asia1 Sindh-08 in the Middle East. In South America, one outbreak of FMDV serotype O, topotype Euro-SA was reported in Paraguay in 2011, which was recognized as FMD-free with vaccination at the time. Lessons learned from past events, point out the need for an integrated strategy that comprises coordinated global and regional efforts for FMDV control and surveillance. Specific local characteristics related to host, environment and virus that condition FMD occurrence should be carefully considered and incorporated to adapt appropriate strategies into local plans. In this review, we compiled relevant epidemiological FMD events to provide a global overview of the current situation. We further discussed current challenges present in different FMD areas.

Effect of cholesterol and ethanol on dermal delivery from DPPC liposomes.

The main objective of the present work was to compare the dermal delivery of minoxidil (Mx), a lipophilic drug from ethosomes versus classic liposomes, containing different cholesterol (CHOL) concentrations. All the systems were characterized for shape, lamellarity, particle size and entrapment efficiency percentage (EE), by transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), laser diffraction and ultracentrifugation or dialysis methods, respectively. Multilamellar vesicles (MLVs) were obtained and one to six lamellae were visualized by CLSM. The presence of ethanol in the formulations affects the particle size in terms of reducing this parameter. In addition, it was possible to appreciate the influence of CHOL on the vesicle size, because it was increased, as CHOL concentration was higher. When the EE was determined by two different methods (ultracentrifugation and dialysis methods), a clear losing of entrapped drug by the ultracentrifugation method was observed, because the strong energy transmitted to the samples disrupted vesicles. Vesicles were non-occlusively applied on rat skin and the permeation pattern of the different systems, depth into the skin and the main permeation pathway were studied by using beta-carotene as a fluorescent probe. CLSM studies showed that ethosomal systems were much more efficient at delivering the fluorescent substance into the skin in terms of quantity and depth, than either liposomes or hydroalcoholic solutions.

Matrix Gla protein gene expression and protein accumulation colocalize with cartilage distribution during development of the teleost fish Sparus aurata.

Matrix Gla protein (MGP) is a member of the family of extracellular mineral-binding Gla proteins, expressed in several tissues with high accumulation in bone and cartilage. Although the precise molecular mechanism of action of this protein remains unknown, all available evidence indicates that MGP plays a role as an inhibitor of mineralization. We investigated the sites of gene expression and protein accumulation of MGP throughout development of the bony fish Sparus aurata, by in situ hybridization, Northern and RT-PCR Southern hybridization, and immunohistochemistry. The results obtained were compared with the patterns of developmental appearance of cartilaginous and mineralized structures in this species, identified by histological techniques and by detection of mRNA presence and protein accumulation of osteocalcin (Bone Gla protein), a marker for osteoblasts known to accumulate in bone mineralized extracellular matrix. The expression of MGP mRNA was first detected at 2 days posthatching (dph) by Northern analysis, RT-PCR amplification, and in situ hybridization, and thereafter continuously detected at various levels of intensity, until 130 dph. In situ hybridization analysis performed in parallel with immunohistochemistry indicated that until ca. 45 dph, the MGP gene was highly expressed in a number of different tissues including skull, jaw, neural and hemal arches, and heart and the protein accumulated in cartilaginous tissues. At 85 dph, a stage when most skeletal structures are mineralized, MGP gene expression and protein accumulation were restricted to the remaining cartilaginous structures, whereas osteocalcin gene expression and protein accumulation were localized in most mineralized structures. MGP gene expression was also detected in heart and kidney, although in situ hybridization only detected MGP mRNA in heart, located in the arterial bulbus and not in the cardiac muscle. Our results are in agreement with those recently described for MGP localization in adult tissues of another teleost fish, as well as available data from higher vertebrates, strengthening the hypothesis of a conserved function for MGP from teleost fish to human, a period of more than 200 million years of evolution. In addition, Sparus aurata, a marine teleost fish routinely grown in captivity, appears to be a good model to further analyze MGP gene expression and regulation.

In vitro targeting of antibody-conjugated echogenic liposomes for site-specific ultrasonic image enhancement.

Tissue-specific ultrasonic enhancement can be used for the detection and characterization of atherosclerosis. We have previously demonstrated the generation of inherently echogenic (acoustically reflective) liposomes solely by varying lipid composition and controlling the method of production. In this study, echogenic liposomes composed of phosphatidylcholine (PC), 4-(p-maleimidophenyl) butyryl phosphatidylethanolamine (MPB-PE), phosphatidylglycerol (PG), and cholesterol were conjugated to human gamma globulin to determine the effect of antibody conjugation on liposomal acoustic reflectivity. The liposomes remained highly echogenic following antibody conjugation. Echogenic liposomes were also conjugated to rabbit antihuman fibrinogen to study their ability to target fibrin. Antibody-conjugated liposomes were targeted to fibrin-coated filter paper and slides, thrombi made in vitro, and segments of atheroma in an animal model of atherosclerosis. Liposomes were detected by scanning electron microscopy, radiolabeling, and imaging with intravascular ultrasound. Electron microscopy revealed attachment of antibody-conjugated liposomes to fibrin on slides and to the fibrous plaques of the arterial segments, whereas unconjugated liposomes did not attach. Similarly, conjugated liposomes did not attach to normal arteries, indicating their binding to the arterial segment is directed towards a component of the fibrous plaque. Ultrasound imaging of the thrombi demonstrated surface attachment of the acoustic conjugated liposomes. 125I-Labeled liposomes conjugated to rabbit anti-human were targeted to fibrin-coated paper. Counting specifically bound radioactivity showed that > 84% of applied liposomes remained attached to the fibrin after washing with saline. These results demonstrate the potential of acoustically reflective liposomes for site-specific targeting and acoustic enhancement.

Investigation on the co-extrudability and spheronization properties of wet masses.

In the present work, preliminary results of co-extrusion and spheronization of wet masses are reported. A ram co-extruder, manufactured in-house, was designed with two concentric single dies mounted on two concentric and independent chambers. This equipment has allowed the production of three types of extrudates (rod or solid extrudates, tubular or hollow extrudates and co-extrudates). Different wet mixtures of microcrystalline cellulose, lactose, a non-soluble in water dye and water were produced and used to feed the chambers of the ram co-extruder. Extrusions of the wet masses were carried out at different speeds of the ram (25-400 mm/min). The extrudates were evaluated according to surface characteristics (by visual inspection), force of extrusion and duration of steady-state (after recording the force applied to the ram and its displacement). Simultaneously, for each process of extrusion it was possible to assess the angles of convergence to the bottom of the chambers for both the external and internal chambers. These angles reflected the high complexity of the extrusion occurring on the external chamber in consequence of its annular geometry, in which the bisecting-line was not parallel to the axis of the extruder, by opposition to the converging angle in the internal chamber, where the bisecting-line was perfectly aligned to the axis of the extruder. Variations in the amount of water in the formulations and the speed of extrusion affected both the production and the quality of the extrudates and their ability to provide pellets. The rod extrudates were the easiest to produce and the relationships between the formulations, the processing conditions and the properties of the extrudates were immediately apparent. On the other hand, co-extrudates were more complex to characterise, although identical relationships between formulations, processing conditions and the properties of the co-extrudates were observed as for the rod extrudates. Different batches of extrudates (rod, tubular and co-extrudates) were spheronized to a maximum spheronization time of 10 min at 1000 rpm. The pellets were characterized with respect to size, size distribution, sphericity and density. Results have shown that for a larger diameter of the co-extrudates, the pellets produced were bigger ( approximately 3.38 mm) than the pellets produced from rod extrudates (1.22 mm). For longer times of spheronization, the aspect ratio and the density increased for both pellets produced from rod (0.95 and 1.46 g/cm(3)) and co-extrudates (0.90 and 1.47 g/cm(3)). The study has shown the potential of this new technology in providing a product with advantages over the traditional spheres produced by extrusion and spheronization.

Using exceedance probabilities to detect anomalies in routinely recorded animal health data, with particular reference to foot-and-mouth disease in Viet Nam.

The widespread availability of computer hardware and software for recording and storing disease event information means that, in theory, we have the necessary information to carry out detailed analyses of factors influencing the spatial distribution of disease in animal populations. However, the reliability of such analyses depends on data quality, with anomalous records having the potential to introduce significant bias and lead to inappropriate decision making. In this paper we promote the use of exceedance probabilities as a tool for detecting anomalies when applying hierarchical spatio-temporal models to animal health data. We illustrate this methodology through a case study data on outbreaks of foot-and-mouth disease (FMD) in Viet Nam for the period 2006-2008. A flexible binomial logistic regression was employed to model the number of FMD infected communes within each province of the country. Standard analyses of the residuals from this model failed to identify problems, but exceedance probabilities identified provinces in which the number of reported FMD outbreaks was unexpectedly low. This finding is interesting given that these provinces are on major cattle movement pathways through Viet Nam.

Epidemiology of serotype Asia 1 foot-and-mouth disease virus in China.

This manuscript provides insight into the epidemiology of serotype Asia 1 foot-and-mouth disease virus in China. The spatial distribution and temporal dynamics of this serotype, which China reported for the first time after 47 years in 2005, suggests that it may have become endemic in the region.

Correlation of the critical micelle concentrations of surfactants with their effects on a bacterial demethylase.

The activity of a sarcosine dehydrogenase isolated from a strain of Pseudomonas is enhanced by the addition of Triton X-100, Brij 35, and Tween 80, and is inhibited by deoxycholate and Sarkosyl NL-97. 2,6-Dichlorophenolindophenol, which is used as the oxidant in the dehydrogenase assay, has also been employed as an indicator in the spectrophotometric determination of the critical micelle concentrations (CMC) of both the nonionic and anionic detergents under conditions optimal for the enzyme analyses. A correlation between the activation or inhibitory activities of the surfactants and their CMC values has been established.

Polyethylene wear debris in modular acetabular prostheses.

The longevity of total hip arthroplasty has brought forth the recognition of aseptic loosening of prosthetic components as the leading cause of implant failure. Modularity of implants, although a significant improvement in versatility, may increase debris formation, a recognized cause of implant failure. This study was designed to measure the relative motion, and to assess the polyethylene wear debris production at the interface between the metal acetabular shell and the back side of the polyethylene liner, in modular hip prostheses. Five models from 4 manufacturers with different locking mechanisms and acetabular shell surface treatments were tested under long-term simultaneous sinusoidal and static loading (10(7) cycles at 3 Hz with +/- 2.5 Nmeter and 220 N static load). Results showed that there were marked differences in the security of the acetabular shell and polyethylene liner locking mechanism, wear pattern, damage sites, and amount of polyethylene debris on the acetabular shell and polyethylene liner surfaces. The range of polyethylene liner motion observed among the 5 models during 1 cycle of testing varied from an average of 0.96 degrees to movement too small to be detected by the test machines. Image and scanning electron microscopy analysis showed different wear patterns and a wide range in the average polyethylene liner surface wear area (0.26 cm2-4.61 cm2). In general, a stable locking mechanism and a smooth acetabular shell surface are essential in minimizing polyethylene liner wear and polyethylene debris production.

Fatigue model to characterize cement-metal interface in dynamic shear.

This study evaluated the interface shear strength between vacuum mixed polymethyl-methacrylate and two types of surface enhancements under static and dynamic shear loading. Cobalt chrome coupons with grit blasted or light plasma sprayed surfaces were tested. For each test, two coupons were mounted in a stainless steel chamber such that they were bonded with a 2-mm cement mantle for each test. Pullout and dynamic fatigue tests were performed on an Instron machine. The mean static pullout strength of the grit blasted surfaces was 13.78 (+/- 2.73) MPa, whereas that of the light plasma sprayed surfaces was 18.46 (+/- 1.98) MPa. The rate of degradation of interface strength caused by fatigue was almost identical for both surface treatments. Qualitative analysis showed that the failed light plasma sprayed surface generated more metal and cement particles. These data suggest that light plasma sprayed surfaces sustain higher loads but have a potential for increased debris generation.

Oxypropylation of cork and the use of the ensuing polyols in polyurethane formulations.

Cork particles, recovered as byproducts of the processing of this natural material, were oxypropylated under pressure and relatively high temperature in the presence of KOH as catalyst. Various parameters were explored in order to assess the most suitable conditions, which led to the almost complete conversion of the solid cork into a viscous polyol. This product was a mixture of oxypropylated cork macromolecules and propylene oxide oligomers, which were thoroughly characterized. The use of these polyols as macromonomers in the synthesis of polyurethane foams gave promising results, thus showing that it should be possible to exploit the residues of this important renewable resource to manufacture original materials.