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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 432-435, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-29966896

RESUMO

A simple, fast, low-cost, portable, and eco-friendly method using a spot test on a paper platform, together with diffuse reflectance spectroscopy, was developed and validated for the quantification of aluminum hydrochloride, a potential neurotoxic agent, in antiperspirant samples. The determination of aluminum hydrochloride was performed at a wavelength of 615 nm, by measuring consumption of the purple colorimetric reagent Alizarin S, due to reaction with aluminum. The linear range was from 10.0 to 125.0 mg L-1 and could be described by the equation: AR = 0.4479 - 0.002543 CAl (R = 0.999). The limits of detection (LOD) and quantification (LOQ) were 3.06 and 10.2 mg L-1, respectively. The method was specific, accurate, and repeatable, with relative standard deviation (RSD) <5.0%. The recovery was between 92.2 and 103.4%. The method was successfully used for the determination of aluminum hydrochloride in commercial antiperspirant samples, revealing concentrations below the maximum permitted by current legislation.


Assuntos
Compostos de Alumínio/análise , Antiperspirantes/química , Cloretos/análise , Colorimetria/métodos , Cloreto de Alumínio , Compostos de Alumínio/química , Antiperspirantes/análise , Cloretos/química , Limite de Detecção , Modelos Lineares , Papel , Reprodutibilidade dos Testes
2.
Int Endod J ; 51(8): 889-900, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29377189

RESUMO

AIM: To investigate the relationship between diabetes mellitus and local/systemic effects of both grey and white mineral trioxide aggregate (MTA) Angelus on bone marker expression. METHODOLOGY: Wistar rats were divided into two groups: healthy and diabetic (Alloxan induced), which were further divided into three subgroups (control, GMTA Angelus and WMTA Angelus). Polyethylene tubes filled with MTA materials or empty tubes were implanted in dorsal connective tissue. On days 7 and 30, blood samples were collected for calcium, phosphorus and ALP measurement. The animals were euthanized; implanted tubes were removed and processed for immunohistochemical analysis of osteocalcin (OCN) and osteopontin (OPN). Kruskal-Wallis followed by Dunn's multiple comparison test was performed for nonparametric data, and anova followed by Tukey's test for parametric data. RESULTS: No difference in systemic serum calcium levels between both groups was observed. On day 7, serum phosphorus levels within the WMTA healthy group were higher than that of the diabetic group. On day 30, healthy rats exhibited lower phosphorus levels than diabetic ones. At both time points, the diabetic group was associated with more ALP activity than the healthy group. Immunohistochemical analyses of the healthy group revealed OCN- and OPN-positive cells in the presence of both MTA materials. However, under diabetic conditions, both OCN and OPN were absent. CONCLUSION: Both MTA materials were associated with an increase in serum calcium, phosphorus and ALP, suggesting a potential systemic effect, along with triggered differentiation of OCN- and OPN-positive cells. Moreover, in diabetic conditions, an inhibitory effect on MTA-induced differentiation of OCN- and OPN-positive cells was detected.


Assuntos
Compostos de Alumínio/análise , Compostos de Cálcio/análise , Diabetes Mellitus Experimental/metabolismo , Óxidos/análise , Silicatos/análise , Animais , Diabetes Mellitus Experimental/sangue , Combinação de Medicamentos , Imuno-Histoquímica , Osteocalcina/análise , Osteopontina/análise , Ratos , Ratos Wistar
3.
Braz Dent J ; 11(1): 3-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11210272

RESUMO

The objective of this study was to investigate the antimicrobial action of mineral trioxide aggregate (MTA), Portland cement, calcium hydroxide paste (CHP), Sealapex and Dycal. The chemical elements of MTA and two Portland cements were also analyzed. Four standard bacterial strains: Staphylococcus aureus (ATCC 6538), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Bacillus subtilis (ATCC 6633), one wild fungus, Candida albicans (ICB/USP-562), and one mixture of these were used. Thirty Petri plates with 20 ml of BHI agar were inoculated with 0.1 ml of the experimental suspensions. Three cavities, each one measuring 4 mm in depth and 4 mm in diameter, were made in each agar plate using a copper coil and then completely filled with the product to be tested. The plates were pre-incubated for 1 h at environmental temperature followed by incubation at 37 degrees C for 48 h. The diameters of the zones of microbial inhibition were then measured. Samples from diffusion and inhibition halos were extracted from each plate and immersed in 7 ml BHI broth and incubated at 37 degrees C for 48 h. Analyses of chemical elements present in MTA and in two samples of Portland cement were performed with a fluorescence spectrometer Rx. The results showed that the antimicrobial activity of CHP was superior to those of MTA, Portland cement, Sealapex and Dycal, for all microorganisms tested, presenting inhibition zones of 6-9.5 mm and diffusion zones of 10-18 mm. MTA, Portland cement, and Sealapex presented only diffusion zones and among these, Sealapex produced the largest zone. Dycal did not show inhibition or diffusion zones. Portland cements contain the same chemical elements as MTA except that MTA also contains bismuth.


Assuntos
Anti-Infecciosos/farmacologia , Cimentos Dentários/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Compostos de Alumínio/análise , Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Antibacterianos , Bacillus subtilis/efeitos dos fármacos , Compostos de Cálcio/análise , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Hidróxido de Cálcio/química , Hidróxido de Cálcio/farmacologia , Candida albicans/efeitos dos fármacos , Cimentos Dentários/análise , Cimentos Dentários/química , Capeamento da Polpa Dentária , Difusão , Combinação de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Humanos , Minerais/química , Minerais/farmacologia , Óxidos/análise , Óxidos/química , Óxidos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/química , Salicilatos/química , Salicilatos/farmacologia , Silicatos/análise , Silicatos/química , Silicatos/farmacologia , Espectrometria de Fluorescência , Staphylococcus aureus/efeitos dos fármacos
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