Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto

About: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto is a based out in . It is known for research contribution in the topics: Population & Genus. The organization has 2143 authors who have published 3674 publications receiving 71071 citations. The organization is also known as: FFCLRP & FFCLRP-USP.

Behavioral effects of intra-amygdala injections of GABA and 5-HT acting drugs in the elevated plus-maze.

Abstract: The effect of drugs bilaterally injected into the basolateral/medial nuclei of the amygdala on the behavior of male Wistar rats (300-330 g) in the elevated plus-maze was measured. The benzodiazepine agonist midazolam (MDZ, 20 and 40 nmol, 0.2 microliters; N = 8-14) significantly increased open-arm exploration (% open-arm entries: control = 20.27 +/- 3.71; 40 nmol MDZ = 42.63 +/- 7.16), having thus an anxiolytic effect. On the contrary, the non-selective 5-HT2 antagonist ketanserin (KET, 1 and 10 nmol, 0.2 microliters; N = 8-11) had an anxiogenic effect (% open-arm entries: control = 35.61 +/- 6.41; 10 nmol KET = 18.65 +/- 3.89). The 5-HT1A full agonist 8-OH-DPAT (2, 4, and 8 nmol, 0.2 microliters; N = 9-12) did not significantly change rat behavior in the plus-maze. While the present anxiolytic effect of midazolam agrees with results reported by others using punished behavior, the effect of the serotonergic drugs does not. Therefore, the effect of 5-HT acting drugs injected into the amygdala may be determined by the type of experimental model of anxiety used.

Chemical composition and antibacterial activity of essential oils from Citrus aurantifolia leaves and fruit peel against oral pathogenic bacteria.

Abstract: Tooth decay is a major public health problem which affects a large number of people in several countries. Even though more than 700 bacterial species have been detected in the oral cavity, Streptococcus and Lactobacillus stand out as the genera that cause tooth decay and other periodontal diseases. In this study, essential oils from Citrus aurantifolia leaves (CL-EO) and fruit peel (CP-EO) were obtained by hydrodistillation by a Clevenger-type apparatus whereas their chemical composition was analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Limonene (77.5 %), linalool (20.1 %), citronellal (14.5 %) and citronellol (14.2 %) were the main constituents found in the essential oils from C. aurantifolia leaves and fruit peel. Antibacterial activity of essential oils was evaluated in terms of its minimum inhibitory concentration (MIC) values by the broth microdilution method in 96-well microplates. Both CL-EO and CP-EO displayed some activity against all oral pathogens under investigation; MIC values ranged from 20 to 200 µg/mL. CL-EO and CP-EO not only had promising activity against Streptococcus mutans (MIC = 20 µg/mL) and Lactobacillus casei (31.25 µg/mL), but also displayed antibacterial activity against all studied cariogenic bacteria. Efficacy of essential oils against S. mutans and L. casei is noteworthy and should be further investigated.

Encapsulation of quercetin in liposomes by ethanol injection and physicochemical characterization of dispersions and lyophilized vesicles

Abstract: Quercetin is a flavonoid with high antioxidant capacity that provides beneficial biological effects However, the absorption rate of quercetin in the gastrointestinal tract is low but encapsulated lipid matrices, such as liposomes, can be useful to enhance its bioavailability In this study, quercetin-loaded liposome dispersions were produced by ethanol injection and 12 mM of phospholipid encapsulating 03% molar quercetin was suitable to evaluate physicochemical stability The Langmuir monolayer technique indicated that it was possible to encapsulate a maximum of 03% molar quercetin in liposomes Quercetin-loaded liposome dispersions presented a mean hydrodynamic diameter of 264 nm and a zeta potential of −17 mV, which is typical for small unilamellar vesicles produced by ethanol injection Sucrose was used as the lyoprotectant (mass sucrose: phospholipid ratio, 4:1), and the encapsulated quercetin had not degraded after 100 days of storage In addition, the lyophilized liposomes presented a low propensity for water adsorption and low hygroscopicity Such behavior is considered highly suitable for stability in dried foods

Electrocatalytic oxidation of ethanol on Pt-Mo bimetallic electrodes in acid medium

Abstract: Pt–Mo alloy electrocatalysts were prepared by an arc-melting furnace process to investigate the origin of their enhanced activity toward ethanol oxidation. Two Mo contents were chosen in zones of the binary phase diagram where they are supposed to form either a pure alloy mixture or a solid solution. Pt–Mo alloy catalysts were more active than Pt-alone. Gradual Mo dissolution at the electrode surface was observed after voltammetric and chronoamperometric measurements. The dissolved Mo contributed to the catalytic effect of the electrode as underpotentially deposited (upd) adatoms. This dissolution probably also leads to an increase in the electrode surface roughness. Low molybdenum content in the electrode material enhances the activity toward ethanol oxidation when compared to Pt-alone. Ethanol oxidation was also investigated by in situ infrared reflectance spectroscopy in order to determine the presence of adsorbed intermediates like CO species. Acetaldehyde, acetic acid and CO2 were also found by spectroscopic experiments.