Avaliação in vitro do pH do hidróxido de cálcio usado como medicação intracanal em associação com clorexidina e racealfatocoferol

Objective: The aim of this study was to evaluate the pH of calcium hydroxide (CalenTM) when associated or not with chlorhexidine 0.4%, and when associated with chlorhexidine with the addition of 20% or 10% of alphatocopherol (AchéTM), assessed in several periods of time. Methods: Fourty dentine tubes 20 mm, properly standardized, were made from bovine anterior teeth roots. Following, a perforation was achieved in the roots distal face at 7 mm from the cervical radicular line by using a #1/2 carbide bur. After complete root sealing is made, except in the perforation local, the radicular canals were filled with one of the following associations: Group I – Calen®; Group II – Calen™ with chlorehxidine at 0.4%; Group III – Calen™ with chlorhexidine at 0.4% with the addition of 20% (weight) of alhatocopherol compound and Group IV – Calen™ with chlorhexidine at 0.4% with the addition of 10% (weight) alphatocopherol. After cervical sealing is accomplished, the roots were immersed in water MiliQ and the pH, assessed in 24h, 7, 14, 21, 28 and 45 days. Results and Conclusion: In all periods tested, the pH of the calcium hydroxide (Calen™) was similar to the pH of the calcium hydroxide (Calen™) associated with chlorhexidine 0.4% and 10% alphatocopherol (p > 0.05). The association of 20% alphatocopherol obtained the pH lower than the association with 10% (p < 0.05). The pH of the association with chlorhexidine was similar to the pure calcium hydrocide (Calen™) after the 14th day (p > 0.05) only. Therefore, on the 45th day, this difference was significant again (p < 0.05).

Compostos de paládio(II) contendo ligantes sulfurados: síntese, caracterização e investigação da atividade biológica

This work deals with the synthesis, spectroscopic characterization of mono and polynuclear Pd(II) compounds obtained from the reaction between [PdCl2(MeCN)2] precursor and imidazolidine-2-thione (L1) and benzimidazoline-2-thione (L2). The interaction between [PdCl2(MeCN)2] and imidazolidine-2-thione, in the 1:2 molar ratio, using MeOH as solvent, yielded compound [Pd2Cl4(L1)4]Cl2 (1) whereas the complex [Pd2Br4(L1)4]Br2 (2) was obtained from the reaction between 1 and Br- ions. Binuclear compounds of general formulae [Pd2(L2)4]X23/2 MeOH {X= Cl-(3), Br-(4)} were synthesized using benzimidazoline-2-thione as ligand, employing the same procedure used in the synthesis of 1 and 2, respectively. The new complexes 1-4 are crystalline, air stable and soluble in methanol and dmso. The compounds were characterized by elemental analysis, IR spectroscopy, ESI/MS mass spectrometry and thermogravimetry. Coordination of the ligands L1 and L2 via sulphur atom was evidenced by the shift of the CS band (~499 cm-1, 1 and 2; ~620 cm-1, 3 and 4) to lower frequencies in comparison with those found in the free ligands (510 cm-1, L1; 660 cm-1, L2), indicating the weakening of the CS bom after coordination. ESI/EM mass spectra (positive mode) of the complexes 1-4 allowed atribute the molecular formulae [Pd2X4(L1)4]X2 {X= Cl-(1), Br-(2)} and [Pd2(L2)4]X2 {X= Cl-(3), Br-(4)} by the appearance of the peaks at m/z 794,61 [(1) + MeOH]+, m/z 836,77 [(2) - 2H - L1]+, m/z 810 [(3) - 2Cl]+, m/z 810 [(4) - 2Br]+. The TG-DTA curves showed that the complexes 1 and 2 are thermally stable up to 212 and 169º C, respectively, and further decompose to metallic palladium at 527º C (1, obt. 28,46 %; calcd. 27,88%) and 895º C (2, obt. 22,85 %; calcd. 22,62%). Compounds 3 and 4 exhibited an initial mass loss of ~5% between 25 -146º C related to the release of metanol molecules. The complexes 3...Fujimura Leite.

Reflexões sobre metodologia aplicada na construção de pesquisas científicas na área de comunicação social

The questions arise about the teaching and practice of the methodology of communication research. The aim is to reflect on the possibility of building research projects and develop research and scientific production in the area of social communication at the graduate level, articulating the epistemological interfaces, methodical, theoretical and methodological techniques for design of empirical research in communication, developed by Lopes (2010), adapting it to the Spiral model of knowledge creation, developed by Takeuchi and Nonaka (2008), to support the learning of the methodological procedures that involve scientific research in communication.

Precision of distances and ordering of microsatellite markers in consensus linkage maps of chromosomes 1, 3 and 4 from two reciprocal chicken populations using bootstrap sampling

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