Evaluation of the dentin-pulp complex after cavity preparation with ultrasonic diamond tip

The aim of this paper was to compare the dentin-pulp complex response to cavity preparation in human teeth using ultrasonic chemical vapor deposition (CVD) diamond tip and high-speed diamond bur. Class V buccal cavities were randomly prepared in 40 premolars from 14 patients aged 11 to 15 years. The cutting time was recorded and the cavities had the axial walls protected with gutta-percha and were filled with glass ionomer cement. The teeth were extracted at intervals of 0, 5, 10 and 20 days, and were decalcified, sectioned and stained by Hematoxylin & Eosin, Masson's Trichrome and Brown & Brenn techniques. The inflammatory response and cell disorganization were blindly evaluated by two examiners. The remaining dentin thickness (RDT) was measured by a linear scale using computer software. Statistical analysis by one-way ANOVA showed no statistically significant difference (P≤0.05) among the cavities prepared with either type of instrument, with mean RDT of 1132.50 mm. Cutting time and the pulp-dentin complex responses were analyzed statistically by Kruskal-Wallis and Dunn tests (P≤0.05). The ultrasonic CVD diamond tip took 5 times longer to prepare the cavities and there were no typical inflammatory pulp responses in cavities prepared with either type of cutting instrument, only mild to moderate cell disorganization was present. Even taking longer to cut the dental substrate, the ultrasonic CVD diamond tip produced similar pulp response compared to the conventional high-speed diamond bur.

Pulp tissue dissolution when the use of sodium hypochlorite and EDTA alone or associated

Purpose: The aim of the present study was to evaluate the tissue dissolving capacity of various concentrations of sodium hypochlorite either alone or in combination with 17% EDTA. Methods: Eighty bovine pulp fragments were prepared, and their weight was determined using a precision balance. Each pulp fragment was immersed for 2 hours in a solution/mixture that was based on the following groups: G1-saline solution; G2-0.5% NaOCl; G3-1.0% NaOCl; G4-2.5% NaOCl; G5-17% EDTA; G6-0.5% NaOCl+17% EDTA; G7-1.0% NaOCl+ 17% EDTA; and G8-2.5% NaOCl+17% EDTA. The final weight was measured, and the weight loss was calculated. A statistical analysis was performed using either the Student's t-test for paired samples or an ANOVA and Tukey tests (P<0.05 was considered to be significant). Results: We measured a significant difference between the sample weight before and after treatment for each of the tested groups (P<0.05). The 2.5% sodium hypochlorite solution (G4) completely dissolved the pulp tissue within the test period. NaOCl+EDTA was less effective than sodium hypochlorite alone at dissolving the pulp tissue (P<0.05), and EDTA alone (G5) did not markedly dissolve the pulp tissue. Conclusion: Using EDTA together with NaOCl reduced the tissue dissolving properties compared with NaOCl alone, regardless of the concentration of NaOCl that was used. © 2011 Só et al.; licensee EDIPUCRS.

Shelf Life of Fresh and Pasteurized Organic Passion Fruit (Passiflora Edulis F. Flavicarpa Deg.) Pulp

The shelf life of the organic passion fruit pulp, both fresh and pasteurized at 70C and 90C and stored under refrigeration, was evaluated. The heat treatment did not affect the sensory and physicochemical characteristics of the pasteurized pulps when compared with the fresh pulp, except for the ascorbic acid content. The pulps were also microbiologically safe. The pulps pasteurized at 70 and 90C were suitable for consumption for a minimum shelf-life period of 207 days of storage under refrigeration and for the fresh pulp it was attributed a shelf-life period of 60 to 90 days. The pulp pasteurized at 70C showed higher acceptance scores for all the attributes and purchase intention scores, suggesting a more stable behavior and higher sensory quality. Practical Applications: This work intended to evaluate the influence of the minimum pasteurization on the sensory acceptance and microbiological and physicochemical characteristics of the organic passion fruit pulp stored under refrigeration, with the aim to identify the shelf life. Heat treatment is one of the processes used for food preservation. Lower pasteurization temperature than that used by the Brazilian industries and storage under refrigeration showed to be appropriate for passion fruit pulp quality. In this way, the microbiological, physicochemical and sensory features of passion fruit were preserved. This work can be used as a reference for passion fruit pasteurization, which is able to increase the shelf life of this fruit while preserving its desirable original features. Journal Compilation © 2012 Wiley Periodicals, Inc.

A hydrogel scaffold that maintains viability and supports differentiation of dental pulp stem cells

Objectives: The clinical translation of stem cell-based Regenerative Endodontics demands further development of suitable injectable scaffolds. Puramatrix™ is a defined, self-assembling peptide hydrogel which instantaneously polymerizes under normal physiological conditions. Here, we assessed the compatibility of Puramatrix™ with dental pulp stem cell (DPSC) growth and differentiation. Methods: DPSC cells were grown in 0.05-0.25% Puramatrix™. Cell viability was measured colorimetrically using the WST-1 assay. Cell morphology was observed in 3D modeling using confocal microscopy. In addition, we used the human tooth slice model with Puramatrix™ to verify DPSC differentiation into odontoblast-like cells, as measured by expression of DSPP and DMP-1. Results: DPSC survived and proliferated in Puramatrix™ for at least three weeks in culture. Confocal microscopy revealed that cells seeded in Puramatrix™ presented morphological features of healthy cells, and some cells exhibited cytoplasmic elongations. Notably, after 21 days in tooth slices containing Puramatrix™, DPSC cells expressed DMP-1 and DSPP, putative markers of odontoblastic differentiation. Significance: Collectively, these data suggest that self-assembling peptide hydrogels might be useful injectable scaffolds for stem cell-based Regenerative Endodontics. © 2012 Academy of Dental Materials.

Sweden and Latin America: comments on the paper by professor Olof Ruin

Señala las diferencias históricas y estructurales y llama la atención sobre las semejanzas entre el desarrollo sociopolítico de Suecia y el de América Latina.

Xylanase and β-Xylosidase from Penicillium janczewskii: Production, Physico-Chemical properties, and application of the crude extract to pulp biobleaching

Extracellular xylanase and β-xylosidase production by a Penicillium janczewskii strain were investigated in liquid cultures with xylan from oat spelts under different physical and chemical conditions. The selected conditions for optimized production of xylanase and β-xylosidase were 7 days, pH 6.5, at 30 °C and 8 days, pH 5.0, at 25 °C, respectively. The xylanase exhibited optimal activity in pH 5.0 at 50 °C and the β- xylosidase in pH 4.0 at 75 °C. The xylanase was more stable at pH 6.0 to 9.5, while the β-xylosidase remained stable at pH ranging from 1.6 to 5.5. The xylanase half-life (T50) at 40, 50, and 60 °C was 183, 15, and 3 min, respectively. β-xylosidase half-life was 144, 8, and 4 min at 50, 65, and 75 °C, respectively. When applied to the biobleaching of Eucalyptus kraft pulp, xylanase dosages of 2 and 4 U/g dried pulp reduced, respectively, kappa number by 3.0 and 3.3 units after 1 h treatment, demonstrating that the use of P. janczewskii xylanases in this process is quite promising. The pulp viscosity was not altered, confirming the absence of cellulolytic enzymes in the fungal extract.

CCL3 and CXCL12 production in vitro by dental pulp fibroblasts from permanent and deciduous teeth stimulated by Porphyromonas gingivalis LPS

Objective: The aim of this study was to compare the production of the chemokines CCL3 and CXCL12 by cultured dental pulp fibroblasts from permanent (PDPF) and deciduous (DDPF) teeth under stimulation by Porphyromonas gingivalis LPS (PgLPS). Material and Methods: Primary culture of fibroblasts from permanent (n=3) and deciduous (n=2) teeth were established using an explant technique. After the fourth passage, fibroblasts were stimulated by increasing concentrations of PgLPS (0 - 10 pg/mL) at 1, 6 and 24 h. The cells were tested for viability through MTT assay, and production of the chemokines CCL3 and CXCL12 was determined through ELISA. Comparisons among samples were performed using One-way ANOVA for MTT assay and Two-way ANOVA for ELISA results. Results: Cell viability was not affected by the antigen after 24 h of stimulation. PgLPS induced the production of CCL3 by dental pulp fibroblasts at similar levels for both permanent and deciduous pulp fibroblasts. Production of CXCL12, however, was significantly higher for PDPF than DDPF at 1 and 6 h. PgLPS, in turn, downregulated the production of CXCL12 by PDPF but not by DDPF. Conclusion: These data suggest that dental pulp fibroblasts from permanent and deciduous teeth may present a differential behavior under PgLPS stimulation.

Documento informativo acerca de la asistencia técnica que se presta a los países y territorios de América Latina en virtud del programa ampliado = Information paper on technical assistance provided to countries and territories of the ECLA region

Incluye Bibliografía

Actividades de asistencia técnica en América Latina durante 1958 = Information paper on technical assistance provided to countries and territories of the ECLA region under the extended programme

Incluye Bibliografía

Effect of pectin extracted from citrus pulp on digesta characteristics and nutrient digestibility in broilers chickens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

ZnO nanostructures directly grown on paper and bacterial cellulose substrates without any surface modification layer

In this report, hierarchical ZnO nano- and microstructures were directly grown for the first time on a bacterial cellulose substrate and on two additional different papers by hydrothermal synthesis without any surface modification layer. Compactness and smoothness of the substrates are two important parameters that allow the growth of oriented structures. © 2013 The Royal Society of Chemistry.