Effect of Ultrasonic Excitation on the Porosity of Glass Ionomer Cement: A Scanning Electron Microscope Evaluation

Background: Ultrasonic excitation (US) was applied to glass ionomer cement (GIC) during early set time to increase the advantageous properties of this material. Purpose: The aim of this in vitro study was to assess the inner porosity of GIC after US. Study design: A total of 16 specimens, for each material, were prepared from high-viscosity GIC Fuji IX GP, Ketac Molar, and Ketac Molar Easymix. Half of these specimens (n = 8) received 30 s of US during the initial cement setting. After completion of the material setting, specimens were fractured and observed by scanning electronic microscopy to quantitatively assay porosity inside the material using Image J software. Results: Statistical data analysis revealed that US reduced the porosity for all tested materials (P <= 0.05). The following reductions (expressed in percentages) were achieved: Fuji IX-from 3.9% to 2.8%; Ketac Molar Easy Mix-from 4.4% to 2.6%, and Ketac Molar-from 2.4% to 1.6%. Conclusion: Under the tested conditions, US was an effective method for porosity reduction inside the material. Microsc. Res. Tech. 74:54-57, 2011. (C) 2010 Wiley-Liss, Inc.

The occurrence of porosity in reline acrylic resins. Effect of microwave disinfection

Microwave energy has proved to be an effective method for disinfecting acrylic dentures. However, the effect of microwave heating on the porosity of autopolymerising denture reline resins has not been investigated.The purpose of the study was to determine the effect of microwave disinfection on the porosity of autopolymerised denture reline materials (Kooliner-K, New Truliner-NT, Tokuso Rebase Fast-TR and Ufi Gel Hard-UGH) and a conventional heat-polymerised denture base resin (Lucitone 550-L).Specimens (10 mm x 20 mm x 1 mm) were obtained from the impression surface of the palatal mucosa in a single person and divided into four groups (n = 5). The porosity was evaluated after polymerisation (C1), after two cycles of microwave disinfection (MW2), after seven cycles of microwave disinfection (MW7) and after 7 days storage in water at 37 degrees C (C2). Specimens from group MW7 were exposed to microwave disinfection daily being stored in water at 37 degrees C between exposures. All the replicas were sputter coated with gold and micrographs/digital images were taken of each replica using scanning electron microscopy at magnification x 100. The SEM micrographs were then examined using an image analyser to determine the number of pores. Comparison between materials and groups were made using Kruskal-Wallis tests.MW7 resulted in a significant increase in the number from the pores of material K, but decreased in number in reline material TR and UGH reline resin. The number of pores in materials NT and L remained unaffected following microwave disinfection.Differences in the porosity amongst the materials and for different experimental conditions were observed following microwave disinfection.

Femtosecond laser ablation on dental hard tissues-Analysis of ablated profile near an interface using local effective intensity

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The sensitization of the ligand-field state of the hexaammineruthenium(II) complex ion by organic compounds

The sensitized photolysis of [Ru(NH3)(6)](2+) by the organic dye rhodamine B and biacetyl was studied under conditions in which only the sensitizer absorbs. The reaction products resulting from ammonia aquation and Ru(II) to Ru(III) oxidation are the same for direct and sensitized photolysis. The energy transfer rate constant, calculated from the fluorescence quenching of rhodamine B, is similar to that estimated from the limiting quantum yield of the photosensitized photoaquation of the complex. Both reactions originate from a common reactive low-lying ligand-field (LF) state, which is also responsible for the direct photolysis reactions. This state, which leads directly to photoaquation, seems to have a certain charge transfer to solvent (CTTS) character, which is responsible for the photo-oxidation products. Sensitization is effective with rhodamine B (17 450 cm(-1)) and biacetyl (19 000 cm(-1)), whereas no reaction is observed with neutral red (16 900 cm(-1)). These results show that the excited state responsible for the photochemical reactions lies in the energy range between 16 900 cm(-1) and 17 700 cm(-1) and possesses spin-orbit character.

Sufentanil-2-hydroxypropyl-beta-cyclodextrin inclusion complex for pain treatment: Physicochemical, cytotoxicity, and pharmacological evaluation

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

Preparation and characterizations of Ba0.8Ca0.2TiO3 by complex polymerization method (CPM)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Clinical Study of a Multivitamin and Polymineral Complex Associated With Panax ginseng Extract (Natus Gerin (R))

This study aimed to stablish the efficacy of a multivitamin and polyminerals supplemented with Panax ginseng extract (Natus Gerin(R)) on patients subjected to common physical or mental stress. Patients were randomly divided in two groups and underwent a thorough clinical examination. Group A received Natus Gerin(R) capsules and B placebo capsules. Two capsules were taken daily during meals during four weeks. Mood and physical activity were evaluated through a questionnaire assessing quality of life. From the 176 patients enrolled, 17 were excluded due to voluntary withdrawal, 81 completed the study in group A and 78 in group B. The treatment with Natus Gerin(R) increased the quality of life when compared to placebo. After 15 and 30 days, group A showed a significant increase in average scoring score from 1.78 to 3.78, and finally 5.32 points. The study has shown that the daily use of Natus Gerin(R) can be effective in improving quality of life in patients suffering from physical and mental stress.

Chemical, spectroscopic characterization, and in vitro antibacterial studies of a new gold(I) complex with N-acetyl-L-cysteine

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

Preparation, characterization and spectroscopy of the europium diphenylphosphinate complex

The purpose of this work is to study the preparation and spectroscopic behavior of the europium diphenylphosphinate complex -Eu(DPP)3. Elemental and thermogravimetric analysis, powder X-ray diffractometry, and infrared spectroscopy were applied to characterize the formula of the final product and the sixfold coordination of the Eu3+ ion. Excitation and emission spectra have been recorded at liquid nitrogen and room temperatures. The 5D0→7F2 transition intensity decreases when T decreases in comparison to the 5D0→7F1 transition intensity. Molecular mechanic calculations were developed in order to obtain the spatial coordinates of the Eu3+ and ligand ions. The simple overlap model was used to calculate the total splitting of the 5D0→7F1 transition, 5D0→7F0/5D 0→7F2 ntensity ratio and the intensity parameters, Ωλ (λ=2 and 4). Good agreements between theoretical predictions and experimental results have been obtained with g=2/3 as the effective charge and α=0.8×10-24 cm3 as the isotropic polarizability of the oxygen. © 1998 Elsevier Science S.A.

L-Histidine-europium(III) complex: A spectroscopical study

Chemical characterization as well as spectroscopical study of the L-histidine-europium(III) complex were developed both experimental and theoretically. Molecular mechanics (MM) simulation was performed in order to have indication of the compound structure and the Eu 3+ chemical environment. The Simple Overlap Model (SOM) was applied to predict spectroscopic quantities as 5D 0→ 7F 0/ 5D 0→ 7F 2 intensity ratio, 5D 0→ 7F 1 transition splitting and the intensity Ω λ parameters (λ = 2 and 4). Satisfactory results are obtained with 0.1 and 2/3 as the effective charges of the nitrogen (gN) and oxygen (gO) respectively, and their polarizabilities (α) depend on the distance. © 1999 Elsevier Science B.V. All rights reserved.

Clinical study of a multivitamin and polymineral complex associated with Panax ginseng extract (Natus Gerin®)

This study aimed to stablish the efficacy of a multivitamin and polyminerals supplemented with Panax ginseng extract (Natus Gerin ®) on patients subjected to common physical or mental stress. Patients were randomly divided in two groups and underwent a thorough clinical examination. Group A received Natus Gerin ® capsules and B placebo capsules. Two capsules were taken daily during meals during four weeks. Mood and physical activity were evaluated through a questionnaire assessing quality of life. From the 176 patients enrolled, 17 were excluded due to voluntary withdrawal, 81 completed the study in group A and 78 in group B. The treatment with Natus Gerin ® increased the quality of life when compared to placebo. After 15 and 30 days, group A showed a significant increase in average scoring score from 1.78 to 3.78, and finally 5.32 points. The study has shown that the daily use of Natus Gerin ® can be effective in improving quality of life in patients suffering from physical and mental stress.

Cost-effective composite electrode for the fast voltammetric screening and determination of riboflavin (B2) and pyridoxine (B6) in pharmaceuticals

Different solid composites made by mechanical dispersions of graphite particles into heated paraffin (from 65 to 80% graphite, in mass) were prepared and assessed in order to optimize their use in electrochemical and electroanalytical procedures for bioanalysis. Besides these, composites were also evaluated by thermoanalytical techniques aiming to study their conservation and long-term stability (over eight months without special care), among others. Best results were found at 80% m/m graphite in paraffin. Such electrode combines low-cost, stability, sensitivity, ease of maintenance and clearance, besides the possibilities of manufacture in many different forms and shapes (with or without modifications) and applicability in a wide range of pH. Electrochemical studies by different voltammetric techniques involving vitamins from complex B (riboflavin and pyridoxine) leaded to a better understanding about their electrooxidative processes onto carbon-composite electrodes, specially regarding reversibility and pH-dependence. Data were also acquired and optimized with analytical purposes, being square-wave voltammetry in pH 4.2 chosen by its many advantages. Good linearity between peak responses as function of concentration were reached from 5 to 43 μmol L-1 for riboflavin (peak at -0.257 V) and up to 8.5 × 10-4 mol L -1 for pyridoxine (peak at +1.04 V), best studied conditions; limits of detection (at an S/N of 3) for both analites showed to be circa 1.0 mol L-1. Different commercial samples were analyzed for riboflavin (EMS® complex B syrup) and pyridoxine (Citoneurin 5000 Merck® ampoules) providing 96.6% and 98.7% recoveries, respectively.

Effect of calcium on the structural properties of Ba(1-x)Ca (x) TiO3 particles synthesized by complex polymerization method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Green chromatographic fingerprinting: An environmentally friendly approach for the development of separation methods for fingerprinting complex matrices

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

Double-Blind clinical study of a multivitamin and polymineral complex associated with Panax ginseng (Gerovital)

The present study aimed to evaluate the efficacy of a multivitamin and poly minerals supplemented with Panax ginseng extract (Gerovital®) on patients suffering from common physical or mental stress. The study design was controlled, parallel and double blind. Patients were randomly divided in two groups and underwent a thorough clinical and laboratory examination. Group A received placebo capsules and group B received Gerovital® capsules. In both cases, two capsules were taken daily during meals for eight weeks. Mood as well as physical activity were evaluated through a questionnaire assessing quality of life. From the 126 patients enrolled, 12 patients (8 in group A and 4 in group B) were excluded due to voluntary withdrawal, 55 patients completed the study in group A and 59 in group B. The treatment with Gerovital® significantly increased the quality of life when compared to placebo. After 15 days of study no difference between groups was observed. However, at 30th, 45th and 60th day, group B showed a statistically significant increase in average score from 30.05 to 41.96, 47.01 and finally 50.81 points. No increase in body weight was detected in either group. No difference in blood pressure or heart rate was also observed between treatments. The present study has shown that the daily use of Gerovital® over a 2-month period can be effective in improving quality of life in patients suffering from physical and mental stress among individuals of different ages, ranging from adults to elderly. Moreover, its use has been associated to a lower incidence of flu-like seasonal respiratory illnesses. Finally, the incidence of undesired effects was similar to placebo.