Effect of Two Restorative Materials on Root Dentine Erosion

This study sought to evaluate the microhardness of root dentine adjacent to glass-ionomer and composite resin restorations after erosive challenge. A crossover study was performed in two phases of 4 consecutive days each. One hundred twelve bovine root dentine slabs were obtained, and standardized box-shaped cavities were prepared at center of each specimen. The prepared cavities were randomly restored with glass-ionomer cement or composite resin. The slabs were randomly assigned among 14 volunteers, which wore intraoral palatal device containing four restored root dentin slabs. Starting on the second day, half of the palatal acrylic devices were immersed extraorally in a lemonade-like carbonated soft drink for 90 s, four times daily for 3 days. Alter 3-day wash-out, dentine slabs restored with the alternative material were placed into palatal appliance and the volunteers started the second phase of this study. After erosive challenges. microhardness measurements were performed. Regardless of the restorative material employed, eroded specimens demonstrated lower microhardness value (p < 0.0001). At eroded condition examined in this study, dentine restored with glass-ionomer cement showed higher microhardness values (p < 0.0001). It may be concluded that the glass-ionomer cement decreases the progression of root dentine erosion at restoration margin. (C) 2010 Wiley Periodicals, Inc J Biomed Mater Res Part B Appl Biomater 93B 304-305, 2010

Chemical and Morphological Features of Dental Composite Resin: Influence of Light Curing Units and Immersion Media

Aims: The study evaluated the influence of light curing units and immersion media on superficial morphology and chemistry of the nanofilled composite resin Supreme XT (3M) through the EDX analysis and SEM evaluation. Light curing units with different power densities and mode of application used were XL 3000 (480 mW/cm(2)), Jet Lite 4000 Plus (1230mW/cm(2)), and Ultralume Led 5 (790 mW/cm(2)) and immersion media were artificial saliva, Coke(R), tea and coffee, totaling 12 experimental groups. Specimens (10 mm X 2 mm) were immersed in each respective Solution for 5 min, three times a day, during 60 days and stored in artificial saliva at 37 degrees C +/- 1 degrees C between immersion periods. Topography and chemical analysis was qualitative. Findings: Groups immersed in artificial saliva, showed homogeneous degradation of matrix and deposition of calcium at the material surface. Regarding coffee, there was a reasonable chemical degradation with loss of load particles and deposition of ions. For tea, superficial degradation occurred in specific areas with deposition of calcium, carbon. potassium and phosphorus. For Coke(R), excessive matrix degradation and loss of load particles with deposition of calcium, sodium, and potassium. Conclusion: Light curing units did not influence the superficial morphology of composite resin tested, but the immersion beverages did. Coke(R) affected material`s surface more than did the other tested drinks. Microsc. Res. Tech. 73:176-181, 2010. (c) 2009 Wiley-Liss Inc.

Dietary fructose, fruits, fruit juices and glucose tolerance status in Japanese-Brazilians

Background and aims: Evidence suggests that fructose and sweetened beverages may be a risk factor for obesity and type 2 diabetes, but the role of sweetened fruit juices in glucose disturbances has been minimally explored. The aim of this study was to examine the association of total fructose, fresh fruit and sweetened fruit juice intake with glucose tolerance homeostasis in Japanese-Brazilians. Methods and results: A total of 475 men and 579 women aged >= 30 years were evaluated in a cross-sectional population-based survey with a standardized protocol including a 2-h oral glucose tolerance test (WHO criteria). Habitual food consumption was obtained using a validated food frequency questionnaire for Japanese-Brazitians. After adjustments for potential confounding variables, the odds ratio (OR; 95%Cl) for impaired glucose tolerance was 2.1 (1.0-4.5; P for trend = 0.05) for the highest as compared to the lowest tertile intake of total fructose and 2.3 (1.1-5.1; P for trend = 0.05) for the highest as compared to the lowest tertile intake of sweetened fruit juices. Conclusion: Our results showed that high intakes of dietary fructose and sweetened fruit juices, but not whole fresh fruits, were associated with impaired glucose tolerance among genetically susceptible individuals. (C) 2008 Elsevier B.V. All rights reserved.

Increasing consumption of ultra-processed foods and likely impact on human health: evidence from Brazil

Objective: To assess time trends in the contribution of processed foods to food purchases made by Brazilian households and to explore the potential impact on the overall quality of the diet. Design: Application of a new classification of foodstuffs based on extent and purpose of food processing to data collected by comparable probabilistic household budget surveys. The classification assigns foodstuffs to the following groups: unprocessed/minimally processed foods (Group 1); processed culinary ingredients (Group 2); or ultra-processed ready-to-eat or ready-to-heat food products (Group 3). Setting: Eleven metropolitan areas of Brazil. Subjects: Households; n 13 611 in 1987-8, n 16 014 in 1995-5 and n 13 848 in 2002-3. Results: Over the last three decades, the household consumption of Group 1 and Group 2 foods has been steadily replaced by consumption of Group 3 ultra-processed food products, both overall and in lower- and upper-income groups. In the 2002-3 survey, Group 3 items represented more than one-quarter of total energy (more than one-third for higher-income households). The overall nutrient profile of Group 3 items, compared with that of Group 1 and Group 2 items, revealed more added sugar, more saturated fat, more sodium, less fibre and much higher energy density. Conclusions: The high energy density and the unfavourable nutrition profiling of Group 3 food products, and also their potential harmful effects on eating and drinking behaviours, indicate that governments and health authorities should use all possible methods, including legislation and statutory regulation, to halt and reverse the replacement of minimally processed foods and processed culinary ingredients by ultra-processed food products.

Determination of sorbate and benzoate in beverage samples by capillary electrophoresis - Optimization of the method with inspection of ionic mobilities

The aim of this study was to develop a fast capillary electrophoresis method for the determination of benzoate and sorbate ions in commercial beverages. In the method development the pH and constituents of the background electrolyte were selected using the effective mobility versus pH curves. As the high resolution obtained experimentally for sorbate and benzoate in the studies presented in the literature is not in agreement with that expected from the ionic mobility values published, a procedure to determine these values was carried out. The salicylate ion was used as the internal standard. The background electrolyte was composed of 25 mmol L(-1) tris(hydroxymethyl)aminomethane and 12.5 mmol L(-1) 2-hydroxyisobutyric acid, atpH 8.1.Separation was conducted in a fused-silica capillary(32 cm total length and 8.5 cm effective length, 50 mu m I.D.), with short-end injection configuration and direct UV detection at 200 nm for benzoate and salicylate and 254 nm for sorbate ions. The run time was only 28 s. A few figures of merit of the proposed method include: good linearity (R(2) > 0.999), limit of detection of 0.9 and 0.3 mg L(-1) for benzoate and sorbate, respectively, inter-day precision better than 2.7% (n =9) and recovery in the range 97.9-105%. Beverage samples were prepared by simple dilution with deionized water (1:11, v/v). Concentrations in the range of 197-401 mg L(-1) for benzoate and 28-144 mg L(-1) for sorbate were found in soft drinks and tea. (c) 2008 Elsevier B.V. All rights reserved.

A multicommuted flow-system for spectrophotometric determination of tannin exploiting the Cu(I)/BCA complex formation

A flow system exploiting the multicommutation approach is proposed for spectrophotometric determination of tannin in beverages. The procedure is based on the reduction of Cu(II) in the presence of 4,4`-dicarboxy-2,2`-biquinoline, yielding a complex with maximum absorption at 558 nm. Calibration graph was linear (r=0.999) for tannic acid concentrations up to 5.00 mu mol L-1. The detection limit and coefficient of variation were estimated as 10 nmol L-1 (99.7% confidence level) and 1% (1.78 mu mol L-1 tannic acid, n=10), respectively. The sampling rate was 50 determinations per hour. The proposed procedure is more sensitive and selective than the official Folin-Denis method, also minimizing drastically waste generation. Recoveries within 91.8 and 115% were estimated for total tannin determination in tea and wine samples. (C) 2007 Elsevier B.V. All rights reserved.

Evaluation of monolithic columns for determination of formaldehyde and acetaldehyde in sugar cane spirits by High-Performance Liquid Chromatography

High-Performance Liquid Chromatography (HPLC) conditions are described for separation of 2,4-dinitrophenylhydrazone (2,4-DNPH) derivatives of carbonyl compounds in a 10 cm long C-18 reversed phase monolithic column. Using a linear gradient from 40 to 77% acetonitrile (acetonitrile-water system), the separation was achieved in about 10 min-a time significantly shorter than that obtained with a packed particles column. The method was applied for determination of formaldehyde and acetaldehyde in Brazilian sugar cane spirits. The linear dynamic range was between 30 and 600 mu g L-1, and the detection limits were 8 and 4 mu g L-1 for formaldehyde and acetaldehyde, respectively.

Use of copper and gold electrodes as sensitive elements for fabrication of an electronic tongue: Discrimination of wines and whiskies

A low-cost method is proposed to classify wine and whisky samples using a disposable voltammetric electronic tongue that was fabricated using gold and copper substrates and a pattern recognition technique (Principal Component Analysis). The proposed device was successfully used to discriminate between expensive and cheap whisky samples and to detect adulteration processes using only a copper electrode. For wines, the electronic tongue was composed of copper and gold working electrodes and was able to classify three different brands of wine and to make distinctions regarding the wine type, i.e., dry red, soft red, dry white and soft white brands. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.

Amino acids profile of sugar cane spirit (cachaca), rum, and whisky

An analytical procedure for the separation and quantification of 20 amino acids in cachacas has been developed involving C18 solid phase cleanup, derivatization with o-phthalaldehyde/2-mercaptoethanol, and reverse phase liquid chromatography with fluorescence detection. The detection limit was between 0.0050 (Cys) and 0.25 (Ser) mg L-1, whereas the recovery index varies from 69.5 (Lys) to 100 (Tyr)%. Relative standard deviations vary from 1.39 (Trp) to 13.4 (Glu)% and from 3.08 (Glu) to 13.5 (His) for the repeatability and intermediate precision, respectively. From the quantitative profile of amino acids in 41 cachacas, 5 turns, and 12 whisky samples, the following order of amino acids in significant quantities is observed: Gly = Ser < Cys < Ile < His < Pro = Asp < Asn < Tyr for cachaca; Phe < Glu = Gln = Val = Ala < His = Gly Thr = Arg = Tyr < Asn Ser = Lys = Pro < Cys = Asp for rum; and Ala = Asn < Trp < Gln = His = Met = Ile = Cys < Thr < Asp Leu < Phe = Lys < Ser = Gly = Tyr = Val < Glu = Pro < Arg for whisky samples. (C) 2007 Elsevier Ltd. All rights reserved.