Piroxicam encapsulated in liposomes: Characterization and in vivo evaluation of topical anti-inflammatory effect

Liposomes of soya phosphatidylcholine, cholesterol, and stearylamine (molar ratio 6/3/1) and 0.1% alpha-tocopherol were prepared by the extrusion of multilamellar vesicles through 0.2-mu m polycarbonate membrane. Liposomes were characterized by electron transmission microscopy, and the mean structure diameter was 278 nm. The encapsulation efficiency obtained was 12.73%. The topical anti-inflammatory effect was evaluated in vivo by the cotton pellet granuloma method. We analyzed free piroxicam at 4 mg/kg, piroxicam encapsulated in liposomes added to 1.5% hydroxyethylcellulose (HEC) gel at 1.6 mg/kg, and piroxicam encapsulated in liposomes added to HEC gel at 4 mg/kg; the inhibition of inflammation obtained was 21.1%, 32.8%, and 47.4%, respectively. These results showed that the encapsulation of piroxicam produced an increase of topical anti-inflammatory effect, suggesting that the inhibition of inflammation can be obtained with lower drug concentrations.

Crescimento de filmes nanométricos monocristalinos de Fe/MgO(100) por "SPUTTERING" DC

The research behind this master dissertation started with the installation of a DC sputtering system, from its first stage, the adaptation of a refrigerating system, passing by the introduction of a heating system for the chamber using a thermal belt, until the deposition of a series of Fe/MgO(100) single crystal nanometric film samples. The deposition rates of some materials such as Fe, Py and Cu were investigated through an Atomic Force Microscope (AFM). For the single crystal samples, five of them have the same growth parameters and a thickness of 250Å, except for the temperature, which varies from fifty degrees from one to another, from 100ºC to 300ºC. Three other samples also have the same deposition parameters and a temperature of 300ºC, but with thickness of 62,5Å, 150Å, and 250Å. Magneto-optical Kerr Effect (MOKE) of the magnetic curves measurements and Ferromagnetic Resonance (FMR) were made to in order to study the influence of the temperature and thickness on the sample s magnetic properties. In the present dissertation we discuss such techniques, and the experimental results are interpreted using phenomenological models, by simulation, and discussed from a physical point of view, taking into account the system s free magnetic energy terms. The results show the growth of the cubic anisotropy field (Hac) as the sample s deposition temperature increases, presenting an asymptotic behavior, similar to the characteristic charging curve of a capacitor in a RC circuit. A similar behavior was also observed for the Hac due to the increase in the samples thicknesses. The 250˚A sample, growth at 300°C, presented a Hac field close to the Fe bulk value

Oxidation of melatonin by AAPH-derived peroxyl radicals: Evidence of a pro-oxidant effect of melatonin

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

The temperature coefficient of the optical path length as a function of the temperature in different optical glasses

An interferometric technique was used to determine the temperature coefficient of the optical path length (dS/dT) as a function of the temperature in several optical glasses. The temperature range was between 25degreesC and 180degreesC. The studied samples included undoped and doped oxide glasses, such as low silica calcium aluminosilicate, phosphates, borates and also chalcogenides. The oxide glasses had dS/dT between 10 X 10(-6) K-1 and 20x10(-6) K-1, while for the chalcogenides, these were around 70 x 10(-6)K(-1). The results showed that dS/dTs increased with the temperature in all samples. For samples doped with Nd the dS/dT values were found to be independent of concentration. on the other hand, for the phosphate glass doped with Cr, dS/dT increased about 5% when compared with the Nd doped one. In conclusion, the used interferometric method, which is a considerably simpler and a lower cost technique, and is a useful tool to measure dS/dT in semi-transparent glasses as a function of the composition and temperature. (C) 2004 Elsevier B.V. All rights reserved.

Inversion in the temperature coefficient of the optical path length close to the glass transition temperature in tellurite glasses

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determination of the sevoflurane sparing effect of methadone in cats

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

3D calculation of Tucson-Melbourne 3NF effect in triton binding energy

As an application of the new realistic three-dimensional (3D) formalism reported recently for three-nucleon (3N) bound states, an attempt is made to study the effect of three-nucleon forces (3NFs) in triton binding energy in a non partial wave (PW) approach. The spin-isospin dependent 3N Faddeev integral equations with the inclusion of 3NFs, which are formulated as function of vector Jacobi momenta, specifically the magnitudes of the momenta and the angle between them, are solved with Bonn-B and Tucson-Melbourne NN and 3N forces in operator forms which can be incorporated in our 3D formalism. The comparison with numerical results in both, novel 3D and standard PW schemes, shows that non PW calculations avoid the very involved angular momentum algebra occurring for the permutations and transformations and it is more efficient and less cumbersome for considering the 3NF.

Evaluation of digital optical density of bone repair in rats medicated with ketoprofen

O objetivo deste estudo foi avaliar a influência do cetoprofeno sobre o processo de reparação óssea em tíbias de ratos, por meio da análise da densidade óptica digital. Vinte ratos da linhagem Wistar foram divididos em 2 grupos: um grupo controle (sem tratamento) e um grupo tratado com cetoprofeno. Os procedimentos experimentais consistiram de: anestesia, cirurgia, administração do cetoprofeno e exame radiográfico. As imagens radiográficas foram adquiridas empregando-se o sensor digital Visualix GX-S-HDI™ e um aparelho de raios X. As radiografias foram realizadas nos períodos baseline (inicial), 7, 14, 21 e 30 dias pós-operatório, sendo a densidade óptica (DO) avaliada por meio do sistema Vix winTM 1.4. Os valores médios da leitura da do obtidos foram analisados estatisticamente por meio de ANOVA e teste de Tukey com nível de significância de 5%. No grupo controle, houve diferença estatisticamente significante (p=0,001) entre o tempo e a DO, enquanto no grupo tratado com cetoprofeno a diferença não foi estatisticamente significante (p=0,100). O grupo controle apresentou as menores proporções de do (%) no 1º e 7º dias e as maiores proporções de do (%) no 14º, 21º e 30º dias, com diferença estatisticamente significante (p=0,001). Não houve diferença estatisticamente significante (p=0,100) entre as proporções médias de do (%) no grupo tratado, independentemente do período de avaliação. Os achados deste trabalho sugerem que houve influência do cetoprofeno sobre o processo de reparo ósseo, uma vez que na primeira semana o medicamento proporcionou aumento na densidade óptica e provocou atraso na neoformação óssea após o 21º dia.

STM probing of local oscillations of the Fano-Kondo effect: a Doniach-Sunjic approach for the Kondo peak

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

FACTORS THAT AFFECT THE ENZYMATIC DEGRADATION OF NATURAL STARCH GRANULES - EFFECT OF THE SIZE OF THE GRANULES

In this study the relationship between the enzymatic susceptibility and the size of the com and cassava starch granules was studied. The starch granules were separated by size and classified according to their average diameter in: a) larger than 16 mum; b) between 15 and 10 mum and c) smaller than 10 mum. The starch granules of various sizes were hydrolyzed by bacterial alpha-amylase and fungal amyloglucosidase. The results showed a relationship between the enzymatic susceptibility and the size of the starch granules; smaller size of the starch granules resulted in a higher percentage of hydrolysis. A basic difference in the mode of action of enzymes on small and large granules was observed. Enzymatic attack on the large granules was characterized by considerable surface corrosion, mainly at the radial axis. For small granules, the enzymatic action occurred on the surface of the granules and was characterized by an erosion with solubilization of the granules. Chemical and physical analysis of the starches suggested that hydrolysis should occur mainly at the amorphous areas of the granules.

Knoop hardness of dental resin cements: Effect of veneering material and light curing methods

This study evaluated the Knoop hardness of one resin cement (dual-cure mode or light-cure mode) when illuminated directly or through restorative materials-ceramic (HeraCeram) or composite (Artglass)-by two light curing units. Light curing was carried out using a conventional quartz tungsten halogen (QTH) light source (XL2500) for 40 s, and a light emitting diodes (LED) light source (Ultrablue Is) for 40 s. Bovine incisors had their buccal faces flattened and hybridised. on these surfaces, a mould was seated and filled with cement. A disc of the veneering material (1.5 mm thickness) was positioned over this set for light curing. After storage (24 h/37 degrees C), samples (n = 10) were sectioned for hardness (KHN) measurements. Data were submitted to ANOVA and to Tukey's test (alpha = 0.05). In general, light curing with LED resulted in higher hardness values than QTH. Distinct cement behaviour was observed with different veneering material in association with different light curing units (LCUs). (C) 2006 Elsevier Ltd. All rights reserved.

Mechanical properties, hydrophilicity and water activity of starch-gum film: effect of additives and deacetylated xanthan gum

The effect of deacetylated xanthan gum, additives (sucrose, soybean oil, sodium phosphate and propylene glycol) and pH modifications on mechanical properties, hydrophilicity and water activity of cassava starch-xanthan gum films has been studied. Sucrose addition resulted in the highest effect observed on cassava starch films elongation at break. The deacetylated xanthan gum had higher effect on elongation at break when comparing to the acetylated gum, although both gums presented an inferior effect in relation to the obtained with sucrose. However, when comparing to the control and PVC films, lower tensile strength resistance values were observed when adding sucrose. Increased water activity was observed for films added with sucrose, thus, increasing the material biodegradation. Sucrose and deacetylated xanthan gum addition resulted in a slight hydrophilicity increase. (C) 2004 Elsevier Ltd. All rights reserved.