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Pashley D.H.,Georgia Regents University | Tay F.R.,Georgia Regents University | Breschi L.,University of Trieste | Breschi L.,CNR Institute of Molecular Genetics | And 5 more authors.
Dental Materials | Year: 2011

Objectives: The aim of this study was to explore the therapeutic opportunities of each step of 3-step etch-and-rinse adhesives. Methods: Etch-and-rinse adhesive systems are the oldest of the multi-generation evolution of resin bonding systems. In the 3-step version, they involve acid-etching, priming and application of a separate adhesive. Each step can accomplish multiple goals. Acid-etching, using 32-37% phosphoric acid (pH 0.1-0.4) not only simultaneously etches enamel and dentin, but the low pH kills many residual bacteria. Results: Some etchants include anti-microbial compounds such as benzalkonium chloride that also inhibits matrix metalloproteinases (MMPs) in dentin. Primers are usually water and HEMA-rich solutions that ensure complete expansion of the collagen fibril meshwork and wet the collagen with hydrophilic monomers. However, water alone can re-expand dried dentin and can also serve as a vehicle for protease inhibitors or protein cross-linking agents that may increase the durability of resin-dentin bonds. In the future, ethanol or other water-free solvents may serve as dehydrating primers that may also contain antibacterial quaternary ammonium methacrylates to inhibit dentin MMPs and increase the durability of resin-dentin bonds. The complete evaporation of solvents is nearly impossible. Significance: Manufacturers may need to optimize solvent concentrations. Solvent-free adhesives can seal resin-dentin interfaces with hydrophobic resins that may also contain fluoride and antimicrobial compounds. Etch-and-rinse adhesives produce higher resin-dentin bonds that are more durable than most 1 and 2-step adhesives. Incorporation of protease inhibitors in etchants and/or cross-linking agents in primers may increase the durability of resin-dentin bonds. The therapeutic potential of etch-and-rinse adhesives has yet to be fully exploited. © 2010 Academy of Dental Materials.

Caixeta G.C.S.,Bandeirante University of Sao Paulo | Dona F.,Bandeirante University of Sao Paulo | Gazzola J.M.,UNIFESP
Brazilian Journal of Otorhinolaryngology | Year: 2012

Abnormal body balance and cognitive dysfunction may develop in elderly patients with chronic vestibular dysfunction. Aim: To evaluate the relationship between cognitive processing and body balance in elderly patients with chronic peripheral vestibular disease. Type of Study: Cross-sectional. Methods: Seventy-six patients (≥ 60 years) with chronic peripheral vestibular dysfunction and dizziness for more than three months were enrolled. The tests for investigating body balance were: the Berg Balance Scale (BBS), Dynamic Gait Index (DGI), Timed Up and Go Test (TUGT) Timed Up and Go Test modified (TUGTm); the Mini Mental State Examination (MMSE), Test Clock (RT,) and Verbal Fluency Test (VF) were applied for assessing cognition. Results: The mean age was 69.03 years (SD=6.21 years); most were female (82.9%). There was a significant negative correlation between the MMSE and the TUGT (ρ=-0.312; p=0.01), MMSE and TUGTm (ρ=-0.306; p=0.01), FV and TUGT (ρ=-0.346; p=0.01), and FV and TUGTm (ρ=-0.536; p=0.01); there was a significant positive correlation between the TR and BBS (ρ=0.343; p=0.01), TR and DGI (ρ=0.298; p=0.01), FV and BBS (ρ=0.299; p=0.01), and FV and DGI (ρ=0.306; p=0.01). Conclusion: Elderly patients with chronic peripheral vestibular disease and worse performance in body balance tests have functional impairment in cognitive skills.

Faiao-Flores F.,Butantan Institute | Faiao-Flores F.,University of Sao Paulo | Suarez J.A.Q.,Bandeirante University of Sao Paulo | Maria-Engler S.S.,University of Sao Paulo | And 3 more authors.
Tumor Biology | Year: 2013

The main difficulty in the successful treatment of metastatic melanoma is that this type of cancer is known to be resistant to chemotherapy. Chemotherapy remains the treatment of choice, and dacarbazine (DTIC) is the best standard treatment. The DM-1 compound is a curcumin analog that possesses several curcumin characteristics, such as antiproliferative, antitumor, and antimetastatic properties. The objective of this study was to evaluate the signaling pathways involved in melanoma cell death after treatment with DM-1 compared to the standard agent for melanoma treatment, DTIC. Cell death was evaluated by flow cytometry for annexin V and iodide propide, cleaved caspase 8, and TNF-R1 expression. Hoechst 33342 staining was evaluated by fluorescent microscopy; lipid peroxidation and cell viability (MTT) were evaluated by colorimetric assays. The antiproliferative effects of the drugs were evaluated by flow cytometry for cyclin D1 and Ki67 expression. Mice bearing B16F10 melanoma were treated with DTIC, DM-1, or both therapies. DM-1 induced significant apoptosis as indicated by the presence of cleaved caspase 8 and an increase in TNF-R1 expression in melanoma cells. Furthermore, DM-1 had antiproliferative effects in this the same cell line. DTIC caused cell death primarily by necrosis, and a smaller melanoma cell population underwent apoptosis. DTIC induced oxidative stress and several physiological changes in normal melanocytes, whereas DM-1 did not significantly affect the normal cells. DM-1 antitumor therapy in vivo showed tumor burden decrease with DM-1 monotherapy or in combination with DTIC, besides survival rate increase. Altogether, these data confirm DM-1 as a chemotherapeutic agent with effective tumor control properties and a lower incidence of side effects in normal cells compared to DTIC. © 2013 International Society of Oncology and BioMarkers (ISOBM).

Faiao-Flores F.,Butantan Institute | Faiao-Flores F.,University of Sao Paulo | Suarez J.A.Q.,Bandeirante University of Sao Paulo | Pardi P.C.,Bandeirante University of Sao Paulo | Maria D.A.,Butantan Institute
Tumor Biology | Year: 2012

This paper describes a new method for the preparation of sodium 4-[5-(4-hydroxy-3-methoxyphenyl)-3-oxopenta-1,4-dienyl]-2-methoxy-phenolate, DM-1, and 3-oxopenta-1,4-dienyl-bis (2-methoxy-phenolate), DM-2. The aim of this work was to evaluate the antitumor effects of DM-1 in adjuvant chemotherapy for breast cancer treatment. Mice bearing mammary adenocarcinomas (Ehrlich ascites tumors) were treated with paclitaxel alone,DM-1 alone, and paclitaxel + DM-1. Tumor samples were used to perform cytological analysis by the Papanicolaou method and apoptosis analysis by annexin Vand phosphorylated caspase 3. The paclitaxel + DM-1 group had decreased tumor areas and tumor volumes, and the frequency of metastasis was significantly reduced. This caused a decrease in cachexia, which is usually caused by the tumor. Furthermore, treatment with paclitaxel + DM-1 and DM-1 alone increased the occurrence of apoptosis up to 40% in tumor cells, which is 35% more than in the group treated with paclitaxel alone. This cell death was mainly caused through phosphorylated caspase 3 (11% increase in paclitaxel + DM-1 compared to the paclitaxel group), as confirmed by reduced malignancy criteria in the ascitic fluid. DM-1 emerges as a potential treatment for breast cancer and may act as an adjuvant in chemotherapy, enhancing antitumor drug activity with reduced side effects. © International Society of Oncology and BioMarkers (ISOBM) 2012.

Rodrigues F.P.,Bandeirante University of Sao Paulo | Silikas N.,University of Manchester | Watts D.C.,University of Manchester | Watts D.C.,Friedrich - Schiller University of Jena | Ballester R.Y.,University of Sao Paulo
Dental Materials | Year: 2012

Objectives: The C-Factor has been used widely to rationalize the changes in shrinkage stress occurring at the tooth/resin-composite interfaces. Experimentally, such stresses have been measured in a uniaxial direction between opposed parallel walls. The situation of adjoining cavity walls has been neglected. The aim was to investigate the hypothesis that: within stylized model rectangular cavities of constant volume and wall thickness, the interfacial shrinkage-stress at the adjoining cavity walls increases steadily as the C-Factor increases. Methods: Eight 3D-FEM restored Class I 'rectangular cavity' models were created by MSC.PATRAN/MSC.Marc, r2-2005 and subjected to 1% of shrinkage, while maintaining constant both the volume (20 mm 3) and the wall thickness (2 mm), but varying the C-Factor (1.9-13.5). An adhesive contact between the composite and the teeth was incorporated. Polymerization shrinkage was simulated by analogy with thermal contraction. Principal stresses and strains were calculated. Peak values of maximum principal (MP) and maximum shear (MS) stresses from the different walls were displayed graphically as a function of C-Factor. The stress-peak association with C-Factor was evaluated by the Pearson correlation between the stress peak and the C-Factor. Results: The hypothesis was rejected: there was no clear increase of stress-peaks with C-Factor. The stress-peaks particularly expressed as MP and MS varied only slightly with increasing C-Factor. Lower stress-peaks were present at the pulpal floor in comparison to the stress at the axial walls. In general, MP and MS were similar when the axial wall dimensions were similar. The Pearson coefficient only expressed associations for the maximum principal stress at the ZX wall and the Z axis. Significance: Increase of the C-Factor did not lead to increase of the calculated stress-peaks in model rectangular Class I cavity walls. © 2011 Academy of Dental Materials. All rights reserved.

Ereifej N.,University of Jordan | Ereifej N.,University of Manchester | Rodrigues F.P.,Bandeirante University of Sao Paulo | Silikas N.,University of Manchester | And 2 more authors.
Dental Materials | Year: 2011

Objectives: To compare the bond strength of a ceramic veneer material to two different ceramic core materials using shear strength testing and finite element analysis (FEA). Methods: 15 blocks of ceramic cores were made of each of IPS e.max ZirCAD (Ivoclar-Vivadent, Schaan, Liechtenstein) (ZirCAD) and lithium disilicate IPS e.max CAD (LS). These were veneered using IPS e.max Ceram (Ceram) according to the manufacturers' instructions. Samples were then mounted, placed inside a shear testing jig and loaded at their core/veneer interfaces with a universal testing machine. Fractured specimens were then examined fractographically at 45×. An independent t-test and a Mann-Whitney U test were used to detect differences in bond strengths and the patterns of failure between the two groups, respectively (p > 0.05). Two-dimensional plane stress FE-models were constructed and subjected to shear loading simulating the experimental conditions. Results: Mean shear stresses (MPa) were 28.8 (9.5) for ZirCAD/Ceram and 29.1 (8.3) for LS/Ceram. Differences were not statistically significant. Fracture patterns were significantly different between the 2 groups as all ZirCAD/Ceram samples broke adhesively at their interface while LS/Ceram samples broke cohesively in the veneer or the core or had mixed adhesive/cohesive failure. Stress distributions in the FEA models were also different, corresponding to the variable fracture patterns in the 2 groups. Significance: Although shear stresses were similar, fractographic analysis and finite element modeling suggested better bonding between the veneering ceramic and the glass-ceramic than to the zirconia cores. Improved bonding techniques are necessary to prevent clinical delamination of veneered zirconia restorations. © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Vila R.,University of Barcelona | Santana A.I.,University of Panamá | Perez-Roses R.,University of Barcelona | Valderrama A.,Instituto Conmemorativo Gorgas En Estudio Of Salud | And 5 more authors.
Bioresource Technology | Year: 2010

The essential oil from fresh leaves of Plinia cerrocampanensis Barrie (Myrtaceae), obtained by hydrodistillation, was analysed by GC-FID and GC-MS. Forty components, representing more than 91% of the oil, were identified. Oxygenated sesquiterpenes represented the main fraction with α-bisabolol (42.8%) as the major constituent, making this plant a new and good source of this substance. Biological activity of the essential oil was evaluated against several bacterial and fungal strains as well as larvae from Aedes aegypti. The highest activity was found against Staphylococcus aureus, Pseudomonas aeruginosa, Microsporum gypseum, Trichophyton mentagrophytes and Trichophyton rubrum with MIC values from 32 to 125 μg/ml. The essential oil also showed potent inhibitory and bactericidal activities against three H. pylori strains, with MIC and MBC values of 62.5 μg/ml, and caused 100% mortality of A. aegypti larvae at a concentration of 500 μg/ml. © 2009 Elsevier Ltd. All rights reserved.

D'Alpino P.H.P.,Bandeirante University of Sao Paulo | Bechtold J.,Bandeirante University of Sao Paulo | Santos P.J.D.,Bandeirante University of Sao Paulo | Alonso R.C.B.,Bandeirante University of Sao Paulo | And 3 more authors.
Dental Materials | Year: 2011

Objectives: To investigate the influence of the energy dose on the hardness, polymerization depth, and internal adaptation of silorane and methacrylate-based posterior composites in Class II restorations with different bonding approaches. Materials and methods: Class II preparations were made on the mesial and distal surfaces of extracted third molars and randomly distributed into 6 groups (n = 20), according to the restorative systems [methacrylate-based composite: Filtek P60 + Adper Single Bond 2 (etch-and-rinse adhesive) - P60/SB; Filtek P60 + Adper Easy One (self-etching adhesive) - P60/EO; silorane-based composite: Filtek P90 + P90 System Adhesive - P90 (self-etching adhesive)] and the energy dose (20 and 40 J/cm2). Resin composites were applied in two increments, individually photoactivated using an LED light-curing unit. After 24 h, all restorations were mesio-distally sectioned. Hardness was evaluated along the transversal section of the fillings (1-4 mm below the restoration surface) using a load of 50 g for 5 s. In order to evaluate the internal gap formation, specimens were air dried and 1% acid red propylene glycol solution was applied to the internal margins for 20 s. Specimens were then water rinsed, air dried, and digitally image recorded. The internal gap (%) was calculated as the ratio between the stained margins and the total length of the internal margin. Kruskal-Wallis test was conducted to evaluate internal gap formation, and three-way ANOVA and Tukey's test were performed to evaluate hardness/polymerization depth (α = 0.05). Results: Regarding the internal gap formation, a significant difference was observed among all groups (P60/EO < P90 < P60/SB), regardless of the energy dose. For 40 J/cm2, a significant increase in gap formation was seen for P60/EO and P90 when compared to 20 J/cm2. The KHN of both resin composites was not affected by the depth of evaluation, but the influence of the material was significant (P60 > P90; p < 0.05). The highest energy dose (40 J/cm2) produced significant increase in the KHN only for Filtek P90 (p < 0.05). Significance: Although a higher energy dose produces a slight increase in hardness for the silorane based composite, it also increases the internal gap formation. Dose of 20 J/cm2 seems to be more suitable as it provides reduced internal gaps and satisfactory hardness. In addition, gap formation seems to be a consequence of an underperformed bonding approach rather than the differences in the resin-composite formulation. © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Araujo G.S.A.,Piracicaba Dental School | Sfalcin R.A.,Piracicaba Dental School | Araujo T.G.F.,Piracicaba Dental School | Alonso R.C.B.,Bandeirante University of Sao Paulo | Puppin-Rontani R.M.,Piracicaba Dental School
Journal of Dentistry | Year: 2013

Objectives To evaluate the properties of experimental infiltrant blends by comparing them with the commercial infiltrant Icon® and penetration homogeneity into enamel caries lesions. Methods Groups were set up as follows: G1 (TEGDMA 100%); G2 (TEGDMA 80%, Ethanol 20%); G3 (TEGDMA 80%, HEMA 20%); G4 (TEGDMA 75%, BisEMA 25%); G5 (TEGDMA 60%, BisEMA 20%, Ethanol 20%); G6 (TEGDMA 60%, BisEMA 20%, HEMA 20%); G7 (TEGDMA 75%, UDMA 25%); G8 (TEGDMA 60%, UDMA 20%, Ethanol 20%); G9 (TEGDMA 60%, UDMA 20%, HEMA 20%) and Icon ®. Ten specimens were comprised by each group for the following tests (n = 10): degree of conversion (DC), elastic modulus (EM), Knoop hardness (KH), and softening ratio (SR). Infiltrant penetration was evaluated using confocal microscopy (CLSM). Data were subjected to two-way ANOVA and a Tukey's test (5%). Data comparing experimental materials and Icon® were analysed using ANOVA and Dunnett's test (5%). Results The highest DC values were found in G1, G7, G8, and G9. The lowest DC values were found in G2, G4, G5, and G6. EM and KHN were significantly lower in HEMA and with ethanol addition for all blends, except for G9. There was no significant difference among the groups regarding SR, and it was not possible to take KHN readings of G2, G5, and G8 after storage. There was no significant difference among groups for infiltrant penetration into enamel lesions. Conclusions The addition of hydrophobic monomers and solvents into TEGDMA blends affected DC, EM, and KHN. UDMA added to TEGDMA resulted in an increase in DC, EM, and KHN. Overall, solvents added to monomer blends resulted in decreased properties. The addition of hydrophobic monomers and solvents into TEGDMA blends does not improve the penetration depth of the infiltrants. © 2013 Elsevier Ltd. All rights reserved.

Gananca M.M.,Federal University of São Paulo | Gananca M.M.,Bandeirante University of Sao Paulo | Caovilla H.H.,Federal University of São Paulo | Gananca F.F.,Federal University of São Paulo
Brazilian Journal of Otorhinolaryngology | Year: 2010

Electronystagmography (ENG) and videonystagmography (VNG) are eye movement recording methods used for the evaluation of balance disorders. Aim: To compare literature information on the similarities, differences, advantages e disadvantages between ENG and VNG. Materials and Methods: review of the scientific literature. Results: ENG and VNG are very helpful methods for evaluating balance disorders, due to their capacity to recognize signs of peripheral or central vestibular dysfunction and to pinpoint the side of the lesion. Major advantages of VNG are related to calibration, temporospatial resolution, and recording of horizontal, vertical and torsional eye movements. Conclusion: VNG is a new technology that presents advantages in the evaluation of eye movements; however, despite its disadvantages, ENG is still considered a valuable test in the clinical setting.

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