In Vitro Assessment of Mutagenic And Genotoxic Effects of Coumarin Derivatives 6,7-Dihydroxycoumarin and 4-Methylesculetin

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

Lethal effect of high concentrations of Parecoxib and Flunixin meglumine on the in vitro culture of bovine embryos

Since cyclooxygenase (COX) inhibitors have been pointed out as potential treatments to increase pregnancy rates after embryo transfer, the present experiment aimed to evaluate the effects of flunixin meglumine (FM) and parecoxib (P), a COX-1 and 2 or COX-2 specific inhibitor, respectively, on the development of bovine embryos until the hatched blastocyst stage. In vitro produced bovine embryos were cultured in media with different concentrations of FM (0.14; 1.4; 14; 140 or 1400 mu g/ml) or P (0.09; 0.9; 9; 90 or 900 mu g/ml) and the production rates were evaluated. Concentrations of FM <= 14 mu g/ml and P <= 90 mu g/ml did not impair embryo development, although compiled data from non-lethal FM concentrations (<= 14 mu g/ml) indicated a toxic effect enough to decrease the hatching rate of blastocysts. Concentrations of FM at 140 and 1400 mu g/ml and P at 900 mu g/ml were lethal as no cleavage was detected on presumptive zygotes.

In vitro performance of a pen-type laser fluorescence device and bitewing radiographs for approximal caries detection in permanent and primary teeth

To evaluate the performance of a pen‑type laser fluorescence device (DIAGNOdent 2190; LFpen, KaVo, Germany) and bitewing radiographs (BW) for approximal caries detection in permanent and primary teeth. Materials and Methods: A total of 246 anterior approximal surfaces (102 permanent and 144 primary) were selected. Contact points were simulated using sound teeth. Two examiners assessed all approximal surfaces using LFpen and BW. The teeth were histologically assessed for the reference standard. Optimal cut‑off limits were calculated for LFpen for primary and permanent teeth. Sensitivity, specificity, accuracy and area under the receiver operating characteristic curve (Az) were calculated for D1 (enamel and dentin lesions) and D3 (dentin lesions) thresholds. The reproducibility was assessed by intraclass correlation coefficient (ICC) and Cohen's weighted kappa values. Results: For permanent teeth, the LFpen cut‑off were 0– 27 (sound), 28– 33 (enamel caries) and >33 (dentin caries). For primary teeth, the LFpen cut‑off were 0– 7 (sound), 8– 32 (enamelcaries) and >32 (dentin caries). The LFpen presented higher sensitivity values than BW for primary teeth (0.58 vs. 0.32 at D1 and 0.80 vs. 0.47 at D3) and permanent teeth (0.80 vs. 0.57 at D1 and 0.94 vs. 0.51 at D3). Specificity did not show a significant difference between the methods. Rank correlations with histology were 0.59 and 0.83 (LFpen) and 0.36 and 0.70 (BW) for primary and permanent teeth, respectively, considering all lesions. ICC values for LFpen were 0.71 (inter) and 0.86 (intra) for permanent teeth and 0.94 (inter) and 0.90/0.99 for primary teeth. Kappa values for BW were 0.69 (inter) and 0.68/0.90 (intra) for permanent teeth and 0.64 (inter) and 0.89/0.89 for primary teeth. Conclusion: LFpen presented better reproducibility for primary and permanent teeth and higher accuracy in detecting caries lesions at D1 threshold than BW for permanent teeth. LFpen should be used as an adjunct method for approximal caries detection.

In vitro study of staining agents effects on optical properties of esthetic restorative materials

The authors have studied the effect of four staining agents on the optical properties of esthetic restorative materials through translucency tests. Two commercial brands of composite resins were used: Point 4 (Kerr) and Charisma (Heraeus-Kulzer). The liquids tested were: wine, cola, chlorhexidine solution and nicotine solution. The translucency was measured at different periods of time: P0 – before immersion (baseline), P1 - 1 h after immersion, P2 - 2 h after immersion and successively, P3 – 24 h after immersion up to a period of 7 weeks. ANOVA statistical analysis was applied to the data (p < 0.05). The results lead to the following conclusions: (1) Composite resins submitted to the tested immersion mediums were stained, (2) the lower percentage of translucency was observed for nicotine containing solution, (3) The percentage of translucency decreased with the period of immersion.

In vitro evaluation of Biosilicate® dissolution on dentin surface: a SEM analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of roof slope and exposure with different roofing materials in reduced models of animal production facilities in spring and summer

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

Effect of sequential medium with fibroblast growth factor-10 and follicle stimulating hormone on in vitro development of goat preantral follicles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro effect of calcium-containing prescription-strength fluoride toothpastes on bovine enamel erosion under hyposalivation-simulating conditions

Purpose: To evaluate the ability of calcium-containing prescription-strength fluoride (F) toothpastes in preventing enamel erosion under low salivary flow simulating conditions. Methods: Enamel and dentin bovine specimens were assigned to the following groups: A - placebo; B - 1,100 ppm F/NaF (Aquafresh Advanced); C - 5,000 ppm F/NaF (Prevident 5000 Booster); D - 5000 ppm F/NaF+calcium sodium phosphosilicate (Topex Renew); and E - 5,000 ppm F/NaF+tri-calcium phosphate (Clinpro 5000). Specimens were positioned in custom-made devices, creating a sealed chamber on the surface, connected to peristaltic pumps. Citric acid was injected into the chamber for 2 minutes, followed by artificial saliva (0.05 ml/minute), for 60 minutes, 4x/day, for 3 days. Aquafresh was also tested under normal salivary flow (0.5 ml/minute), as reference (Group F). Specimens were exposed to the toothpastes for 2 minutes, 2x/day. After cycling, surface loss (SL) and concentration of loosely- and firmly-bound F were determined. Data were analyzed by ANOVA. Results: Group A (placebo) presented highest surface loss (SL), while Group F had the lowest, for both substrates. For enamel, none of the dentifrices differed from Group B or among each other. For dentin, none of the dentifrices differed from Group B, but Group E showed greater protection than Group C. Group E presented the highest F concentrations for both substrates, only matched by Group D for firmly-bound fluoride on enamel. All fluoridated dentifrices tested reduced SL, with no additional benefit from higher F concentrations. Some formulations, especially Clinpro 5000, increased F availability on the dental substrates, but no further erosion protection was observed.

Chemical composition and in vitro digestibility of fresh sugarcane hydrolysed with calcium oxide (CaO)

The objective was to evaluate the chemical composition and in vitro digestibility of sugarcane hydrolysed with increasing doses of calcium oxide and varying air exposure times. A completely randomised, split plot design was used; the doses were allocated to the plots, and the air exposure times were allocated to the subplots, with four repetitions. The data underwent analysis of variance and were laid out according to the effect of the treatment on the components of polynomial regressions, and evaluated at the 5% probability. The increase in the dosage negatively affected the quantities of neutral-detergent fibre (NDF), acid-detergent fibre (ADF), lignin (LIG), total carbohydrates (TC), cellulose (CEL), crude protein (CP), and ether extract (EE); and positively affected the quantities of non-fibrous carbohydrates (NFC) and mineral matter (MM). The addition of calcium oxide improved the in vitro digestible dry matter (IVDMD) coefficients and was able to keep up to 72 hours. The in vitro digestibility of the neutral-detergent fibre (IVDNDF) and of the acid-detergent fibre (IVDADF) coefficients decreased when calcium oxide was added. Calcium oxide has the ability to hydrolyse the fibrous fraction and conserve chopped sugarcane. Doses of 0.5 and 1.0% lime exhibited similar results to those achieved at higher doses; therefore, higher doses are not required in the hydrolyses of sugarcane. Over time, the sugarcane deteriorates, but this deterioration is reduced by the addition of calcium oxide.

Influence of Insulin-like Growth Factor I (IGF-I) on the survival and the in vitro development of caprine preantral follicles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The prophenoloxidase system and in vitro interaction of Trypanosoma rangeli with Rhodnius prolixus and Triatoma infestans haemolymph

The presence of the prophenoloxidase (proPO) system in the haemolymph of Rhodnius prolixus and Triatoma infestans and the role played by Trypanosoma rangeli in the in vitro activation of proPO were tested. Both R. prolixus and T. infestans whole blood preparations showed a very active ProPO system. The proPO cascade of the two insect species were differentially activated by microbial-derived extracts: laminarin was a better activator of T. infestans haemolymph than of R. prolixus blood, and lipopolysaccharides from Shigella flexneri or Pseudomonas aeroginosa caused significant proPO activation of T. infestans haemolymph but not of R. prolixus preparations. For the two insect species, neither T. rangeli from culture nor parasite lysates were able to trigger proPO activation. The presence of the parasite in R. prolixus haemolymph/laminarin assays, however, significantly reduced the level of proPO activation to that of spontaneous activating controls. The immobilization of T. rangeli in vitro in haemolymph preparations occurred in both insect species and was dependent on the proPO activation intensity. Our results suggest that the susceptibility of R. prolixus to T. rangeli haemocoel infection may be explained, at least in part, by the suppression of the insect immune defence system i.e., inhibition of proPO in the presence of this protozoan parasite.

In vitro effect of sodium trimetaphosphate additives to conventional toothpastes on enamel demineralization

The aim of this study was to evaluate the ability of conventional toothpastes (1100 ppm F) supplemented with sodium trimetaphosphate (TMP) in demineralization. Blocks of enamel were selected and then divided into seven experimental groups of 12: toothpaste without F and TMP (placebo), toothpaste with 1100 ppm F (1100), and toothpaste with 1100 ppm F supplemented with TMP-1 % (1100 1 % TMP), 3 % (1100 3 % TMP), 4.5 % (1100 4.5 % TMP), 6 % (1100 6 % TMP), and 9 % (1100 9 % TMP). Blocks were subjected to five pH cycles (demineralizing/remineralizing solutions) at 37 °C and treated with toothpaste slurries twice daily, after which the blocks were maintained for 2 days in fresh remineralizing solution. Following treatments, surface hardness (SHf) and cross-sectional hardness were determined for calculating the integrated loss of subsurface hardness (ΔKHN). The fluoride present in the enamel was also measured. The SHf and ΔKHN measurements showed that supplementation with 3 % TMP was the most effective (p < 0.001) and showed greater concentration of F in the enamel (p < 0.001). Addition of 3 % TMP to a conventional toothpaste (1100 ppm F) showed greater efficacy in reducing enamel demineralization. Fluoride toothpastes containing trimetaphosphate possess good anticaries potential required to reduce the prevalence of dental caries in high-risk patients.

In vitro effect of caffeic acid phenethyl ester on matrix metalloproteinases (MMP-1 and MMP-9) and their inhibitor (TIMP-1) in lipopolysaccharide-activated human monocytes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)