Sodium titanate as basic catalyst in transesterification reactions

Sodium titanate was synthesized by the sol-gel method and characterized using X-ray diffraction, thermogravimetry-mass spectrometry, atomic absorption spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and nitrogen physisorption. The non-calcined material was active as a catalyst in transesterification reactions and showed high stability. An appreciable loss of activity on the fourth reuse was accompanied by the appearance of a new species of oxygen and segregated sodium, identified by X-ray photoelectron spectroscopy (XPS). The XPS spectrum showed that the basic nature of the framework oxygen was inferior to the original basicity, which explained the decline in catalytic activity. (C) 2013 Elsevier Ltd. All rights reserved.

Thermal behaviour of nicotinic acid, sodium nicotinate and its compounds with some bivalent transition metal ions

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

Protective role of melatonin in mouse spermatogenesis induced by sodium arsenite

Arsenic is a testicular environmental toxic. Melatonin (Me), being a potent antioxidant, may reduce the damage caused by arsenic in male fertility. The effects of daily oral exposure of Sodium Arsenite (As; 7.0 mg/kg/bw); Melatonin (Me, 10.0 mg/kg/bw); Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw), and Negative Control (NaCl 0.9%) in male CF-1 adult mice were assessed in acute (8.3 days), chronic (33.2 days) and recovery (66,4 days) of testicular damage. We evaluated changes in testicular weight and histopathological, morphometric measurements, expression of COX-2 and Androgen Receptor (AR) antigens and lipid peroxidation levels. Treatment resulted in decreased tubular diameter and AR expression, and increased: interstitial area, luminal diameter, COX-2 expression levels and of lipid peroxidation. Co-administration of As and Me partially decreased germ cell degeneration and AR expression levels, improving testicular histopathological parameters. These results indicate that As causes toxicity and testicular germ cell degeneration by induction of oxidative stress. Me partially protects from this damage in mouse testis, acting as scavenger of oxygen radical species.

Melatonin Protective Role in Mouse Cauda Epipidymal Spermatozoa Damage Induced by Sodium Arsenite

We evaluated the sperm parameters such as cauda epididymis weight, sperm count, sperm morphology and sperm DNA stability of adult CF-1 male mice treated daily (oral exposure) with the toxic sodium arsenite (As, 7.0 mg/kg/body weight); Melatonin (Me, 10.0 mg/kg/bw), Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw) and Negative Control (NaCl 0.9%) to assess acute (8.3 days), chronic (33.2 days) and recovery of testicular damage (66.4 days). Arsenic decreases the number of sperm from chronic treatment (33.2 days) and this effect continued until 66.4 days of treatment. The toxic effect of As also altered the morphology of spermatozoa in all treatment periods when compared to the negative control group. However, Metalonin induced protective effects in periods of 33.2 and 66.4 days of treatment. Additionally, the stability of DNA was significantly affected by arsenic in all periods, but the chronic treatment (33.2 days) in the AsMe revealed increased stability compared to the group treated with arsenic only. Melatonin partially protects sperm toxicity caused by Arsenic, especially during periods of 33.2 and 66.4 days.

Effect of Sodium Ascorbate on Dentin Bonding After Two Bleaching Techniques

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

Development and validation of a microbiological assay by turbidimetry to determine the potency of cefazolin sodium in the lyophilized powder form

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

Development and validation of a rapid turbidimetric assay to determine the potency of ampicillin sodium in powder for injectable solution

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

Effect of fluoride gels supplemented with sodium trimetaphosphate on enamel erosion and abrasion: In vitro study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Er:YAG-Laser and Sodium Hypochlorite Influence on Bond to Dentin

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

Role of the lateral parabrachial nucleus in the control of sodium appetite

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

Development and Validation of A Stability-Indicating Mekc Method for Determination of Flucloxacillin Sodium in Capsules

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of resin composites with sodium trimetaphosphate with or without fluoride on hardness, ion release and enamel demineralization

Purpose: To evaluate the effect of the addition of sodium trimetaphosphate (TMP) with or without fluoride on enamel demineralization, and the hardness and release of fluoride and TMP of resin composites. Methods: Bovine enamel slabs (4x3x3 mm) were prepared and selected based on initial surface hardness (n= 96). Eight experimental resin composites were formulated, according to the combination of TMP and sodium fluoride (NaF): TMP/NaF-free (control), 1.6% sodium fluoride (NaF), and 1.5%, 14.1% and 36.8% TMP with and without 1.6% NaF. Resin composite specimens (n= 24) were attached to the enamel slabs with wax and the sets were subjected to pH cycling. Next, surface and cross-sectional hardness and fluoride content of enamel as well as fluoride and TNT release and hardness of the materials were evaluated. Data were statistically analyzed using ANOVA (P< 0.05). Results: The presence of fluoride in enamel was similar in fluoridated resin composites (P> 0.05), but higher than in the other materials (P< 0.05). The combination of 14.1% TMP and fluoride resulted in less demineralization, especially on lesion surface (P< 0.05). The presence of TMP increased fluoride release from the materials and reduced their hardness.

Effect of fluoride varnish supplemented with sodium trimetaphosphate on enamel erosion and abrasion: An in situ/ex vivo study

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

In vitro Remineralizing Effect of Fluoride Varnishes Containing Sodium Trimetaphosphate

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of fluoride gels supplemented with sodium trimetaphosphate in reducing demineralization

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