Effect Of Salivary Contamination At Different Steps Of The Bonding Process On The Microleakage Around Class V Restorations

This study aimed to investigate the influence of the moment of salivary contamination during the bonding procedure (before or after acid conditioning) on the microleakage around composite resin restorations. Sixty bovine incisors received two Class V preparations (one with dentin margins and other with enamel margins). Teeth were randomly assigned into three, groups (n-20): 1) control (not contaminated); 2) salivary contamination before etching with 34% phosphoric acid; and, 3) salivary contamination after acid etching. Cavities were restored using Prime & Bond NT (Dentsply) adhesive system and TPH Spectrum (Dentsply) composite according to manufacturer instructions. Teeth were thermocycled (500x, 5-55°C, 60s/bath), immersed in 2% methylenee blue buffered solution (pH 7.0), and sectioned into two halves. Three examiners measured the extent of dye penetration or dentin and enamel margins in a stereoscope microscope, using four representative scores. Statistical analysis were performed with Kruskal-Wallis/Wilcoxon tests (α-5%). The results showed that enamel and dentin margins did not present significant differences (p>0.05). However, significantly higher dye penetration was observed on substrates etched and further contaminated with saliva. It was concluded that salivary contamination after acid etching increases the microleakage around composite resin restorations, especially at dentin margins. However, acid etching subsequent to the contamination can avoid negative effects on restorations margins.62314451449Van Meerbeek, B., Van Landuyt, K., De Munck, J., Hashimoto, M., Peumans, M., Lambrechts, P., Technique -sensitivity of contemporary adhesives (2005) Dent Mater J, 24, pp. 1-13Civelek, A., Ersoy, M., L'Hotelier, E., Soyman, M., Say, E.C., Polymerization shrinkage and microleakage in Class II cavities of various resin composites (2003) Oper Dent, 28, pp. 635-641Besnault, C., Attal, J.P., Influence of a simulated oral environment on microleakage of two adhesive systems in Class II composite restorations (2002) J Dent, 30, pp. 1-6Spencer, P., Wang, Y., Bohaty, B., Interfacial chemistry of moisture-aged class II composite restorations (2006) J Biomed Mater Res B Appl Biomater, 77, pp. 234-240Direct and indirect restorative materials (2003) J Am Dent Assoc, 134, pp. 463-472. , Council on Scientific Affairs ADASoldani, F., Foley, J., An assessment of rubber dam usage amongst specialists in paediatric dentistry practising within the UK (2007) Int J Paediatr Dent, 17, pp. 50-56Fernandes, A.S., Rodrigues, S., Singhal, K., Murthi, M.S., Assessment of chair side techniques for composite resin restoration - a survey (2003) Indian J Dent Res, 14, pp. 47-56Taskonak, B., Sertgoz, A., Shear bond strengths of saliva contaminated 'one-bottle' adhesives (2002) J Oral Rehabil, 29, pp. 559-564Eiriksson, S.O., Pereira, P.N., Swift Jr., E.J., Heymann, H.O., Sigurdsson, A., Effects of saliva contamination on resin-resin bond strength (2004) Dent Mater, 20, pp. 37-44Hiraishi, N., Kitasako, Y., Nikaido, T., Nomura, S., Burrow, M.F., Tagami, J., Effect of artificial saliva contamination on pH value change and dentin bond strength (2003) Dent Mater, 19, pp. 429-434Park, J.W., Lee, K.C., The influence of salivary contamination on shear bond strength of dentin adhesive systems (2004) Oper Dent, 29, pp. 437-442Yoo, H.M., Oh, T.S., Pereira, P.N., Effect of saliva contamination on the microshear bond strength of one-step self-etching adhesive systems to dentin (2006) Oper Dent, 31, pp. 127-134Hitmi, L., Attal, J.P., Degrange, M., Influence of the time-point of salivary contamination on dentin shear bond strength of 3 dentin adhesive systems (1999) J Adhes Dent, 1, pp. 219-232Reis, A.F., Giannini, M., Kavaguchi, A., Soares, C.J., Line, S.R., Comparison of microtensile bond strength to enamel and dentin of human, bovine, and porcine teeth (2004) J Adhes Dent, 6, pp. 117-121Eiriksson, S.O., Pereira, P.N., Swift, E.J., Heymann, H.O., Sigurdsson, A., Effects of blood contamination on resin-resin bond strength (2004) Dent Mater, 20, pp. 184-190Toledano, M., Osorio, R., Ceballos, L., Fuentes, M.V., Fernandes, C.A., Tay, F.R., Microtensile bond strength of several adhesive systems to different dentin depths (2003) Am J Dent, 16, pp. 292-29

Coarsening in 2D slabs

We study coarsening; that is, the zero-temperature limit of Glauber dynamics in the standard Ising model on slabs S_k = Z^2 x {0, ..., k-1} of all thicknesses k \geq 2 (with free and periodic boundary conditions in the third coordinate). We show that with free boundary conditions, for k \geq 3, some sites fixate for large times and some do not, whereas for k=2, all sites fixate. With periodic boundary conditions, for k \geq 4, some sites fixate and others do not, while for k=2 and 3, all sites fixate.Comment: 8 pages, 2 figure

Phase Transition in Ferromagnetic Ising Models with Non-Uniform External Magnetic Fields

In this article we study the phase transition phenomenon for the Ising model under the action of a non-uniform external magnetic field. We show that the Ising model on the hypercubic lattice with a summable magnetic field has a first-order phase transition and, for any positive (resp. negative) and bounded magnetic field, the model does not present the phase transition phenomenon whenever $\liminf h_i> 0$, where ${\bf h} = (h_i)_{i \in \Z^d}$ is the external magnetic field.Comment: 11 pages. Published in Journal of Statistical Physics - 201

Influence of dietary Chlorella vulgaris and carbohydrate-active enzymes on growth performance, meat quality and lipid composition of broiler chickens

Article in pressHerein, we investigated the effect of Chlorella vulgaris as ingredient (10% of incorporation) in broiler diets, supplemented or not with 2 formulations of Carbohydrate-Active enZymes (CAZymes; Rovabio Excel AP and a mixture of recombinant CAZymes, composed by an exo-b-glucosaminidase, an alginate lyase, a peptidoglycan N-acetylmuramic acid deacetylase and a lysozyme), on growth performance, meat quality, fatty acid composition, oxidative stability, and sensory traits. One hundred twenty 1-day-old Ross 308 male birds were randomly assigned to one of the 4 experimental diets (n 5 30): corn-soybean meal–basal diet (control), basal diet with 10% C. vulgaris (CV), CV supplemented with 0.005% of a commercialCAZymecocktail (Rovabio Excel AP), (CV1R), and CV supplemented with 0.01% of a 4- CAZyme mixture previously selected (CV 1 M) during the experimental period lasted from day 21 to day 35. Body weight gain and feed conversion rate of broilers were not affected by C. vulgaris but digesta viscosity increased more than 2-fold (P , 0.001) relative to the control. In addition, neither cooking loss, shear force, juiciness, flavor nor off-flavor was impaired by dietary treatments (P.0.05). By contrast, the dietary C. vulgaris increased tenderness, yellowness (b*) and total carotenoids in breast and thigh meats. However, no additional protective effect against lipid oxidation was observed in meat with the inclusion of microalga. Chlorella vulgaris, independently of CAZymes, had a minor impact on meat fatty acid composition but improved the proportion of some beneficial fatty acids. In summary, our data indicate a slight improvement of broiler meat quality and lipid nutritional value, without impairment of broilers’ growth performance, thus supporting the usefulness of this microalga in poultry diets, up to this high level of incorporation. By contrast, the selected CAZyme mixtures used do not significantly improve the release of microalga nutrients in poultry diets, through the disruption of microalga cell wall, which warrants further researchinfo:eu-repo/semantics/acceptedVersio

Historical separation and present-day structure of common dolphinfish (Coryphaena hippurus) populations in the Atlantic Ocean and Mediterranean Sea

The common dolphinfish (Coryphaena hippurus) is an epipelagic, mid-trophic level, highly migratory species distributed throughout the world’s tropical and subtropical oceans in waters greater than 20C. Life-history variables, migratory behaviour, and genetic markers have been used to define major stocks in the central Atlantic Ocean and Mediterranean Sea. Here, we used the mitochondrial DNA gene NADH subunit 1 (688 bp) to test for differences between population groups. A total of 103 haplotypes were detected among 203 fish. Gene diversities in samples were large and similar among populations (mean h ¼ 0.932; range 0.894–0.987), but nucleotide diversities varied widely among samples (range p ¼ 0.004–0.034) and appear to reflect population histories. Principal component analysis revealed two large populations groups, and the analysis of molecular variation and pairwise values of UST resolved population structure within these groups. Populations in the eastern Atlantic and Mediterranean showed the largest amounts of divergence from one another (UCT ¼ 0.331). Adult movement and biophysical barriers to larval dispersal may explain contemporary differences between stocks, but the divergent populations in the Mediterranean Sea are likely due to isolations by cold temperature barriers during Pleistocene glaciations. The geographically large stock groupings require international cooperation in the harvest management and conservation of local dolphinfish populations

A PRND polymorphism in Churra do Campo portuguese sheep breed

Prion-like Doppel gene (PRND) is located downstream from priori protein gene (PRNP). Doppel protein is not related to prion disease but to male fertility. Our previous analysis of PRND coding region in 460 animals from 8 Portuguese sheep breeds, by multiple restriction fragment-single strand conformation polymorphism (MRFSSCP), revealed a synonymous substitution (78G>A). An association was found between identified PRND polymorphism and PRNP genotypes, determined by primer extension and grouped into 5 grades of increasing scrapie susceptibility-R1 to R5: PRND was monomorphic (GG) in animals with most resistant ARR/ARR PRNP genotype-R1; higher frequency of heterozygotes (GA) was significantly associated with ARQ/AHQR4. Therefore, EU selection programme to eradicate scrapie in sheep, based on PRNP genotypes, may reduce genetic diversity, with hypothetical repercussions on reproduction. The aim of current work was to evaluate 78G>A PRND polymorphism in highly endangered Churra do Campo Portuguese sheep breed. From a total of 73 animals analysed (16 R1, 36 R3, 18 R4, 3 R5), 72 were GG and 1 GA, the later being ARQ/ARQ (R4). Low incidence of PRND polymorphic variants in this breed may be explained by mating involving small number of related animals, and particular differences in distribution of PRNP genotypes

Predicting stroke through genetic risk functions: the CHARGE Risk Score Project.

BACKGROUND AND PURPOSE: Beyond the Framingham Stroke Risk Score, prediction of future stroke may improve with a genetic risk score (GRS) based on single-nucleotide polymorphisms associated with stroke and its risk factors. METHODS: The study includes 4 population-based cohorts with 2047 first incident strokes from 22,720 initially stroke-free European origin participants aged ≥55 years, who were followed for up to 20 years. GRSs were constructed with 324 single-nucleotide polymorphisms implicated in stroke and 9 risk factors. The association of the GRS to first incident stroke was tested using Cox regression; the GRS predictive properties were assessed with area under the curve statistics comparing the GRS with age and sex, Framingham Stroke Risk Score models, and reclassification statistics. These analyses were performed per cohort and in a meta-analysis of pooled data. Replication was sought in a case-control study of ischemic stroke. RESULTS: In the meta-analysis, adding the GRS to the Framingham Stroke Risk Score, age and sex model resulted in a significant improvement in discrimination (all stroke: Δjoint area under the curve=0.016, P=2.3×10(-6); ischemic stroke: Δjoint area under the curve=0.021, P=3.7×10(-7)), although the overall area under the curve remained low. In all the studies, there was a highly significantly improved net reclassification index (P<10(-4)). CONCLUSIONS: The single-nucleotide polymorphisms associated with stroke and its risk factors result only in a small improvement in prediction of future stroke compared with the classical epidemiological risk factors for stroke