Nails have been suggested as suitable biomarkers of exposure to F, with the advantage of being easily obtained. The effect of water F concentration, age, gender, nail growth rate and geographical area on the F concentration in the fingernail and toenail clippings were evaluated. Volunteers (n = 300) aged 3–7, 14–20, 30–40 and 50–60 years from five Brazilian communities (A–E) participated. Drinking water and nail samples were collected and F concentration was analyzed with the electrode. A reference mark was made on each nail and growth rates were calculated. Data were analyzed by ANOVA and linear regression (α = 0.05). Mean water F concentrations (± SE, mg/l) were 0.09 ± 0.01, 0.15 ± 0.01, 0.66 ± 0.01, 0.72 ± 0.02, and 1.68 ± 0.08 for A–E, respectively. Mean F concentrations (± SE, mg/kg) ranged between 1.38 ± 0.14 (A, 50–60 years) and 10.20 ± 2.35 (D, 50–60 years) for fingernails, and between 0.92 ± 0.08 (A, 14–20 years) and 7.35 ± 0.80 (E, 50–60 years) for toenails. Among the tested factors, geographical area and water F concentration exerted the most influence on finger- and toenail F concentrations. Subjects of older age groups (30–40 and 50–60 years) from D and E showed higher nail F concentrations than the others. Females presented higher nail F concentration than males. Water F concentration, age, gender and geographical area influenced the F concentration of finger- and toenails, and hence should be taken into account when using this biomarker of exposure to predict risk for dental fluorosis.

The aim of this study was to validate the use of fingernail fluoride concentrations at ages 2–7 years as predictors of the risk for developing dental fluorosis in the permanent dentition. Fifty-six children of both genders (10–15 years of age) had their incisors and premolars examined for dental fluorosis using the Thylstrup-Fejerskov index. Fingernail fluoride concentrations were obtained from previous studies when children were 2–7 years of age. Data were analyzed by unpaired t test, ANOVA, and Fisher’s exact test when the fingernail fluoride concentrations were dichotomized (≤2 or >2 µg/g). Children with dental fluorosis had significantly higher fingernail fluoride concentrations than those without the condition, and the concentrations tended to increase with the severity of fluorosis (r² = 0.47, p < 0.0001). Using a fingernail fluoride concentration of 2 µg/g at ages 2–7 years as a threshold, this biomarker had high sensitivity (0.84) and moderate specificity (0.53) as a predictor for dental fluorosis. The high positive predictive value indicates that fingernail fluoride concentrations should be useful in public health research, since it has the potential to identify around 80% of children at risk of developing dental fluorosis.

Objectives:The aims of the present study were to evaluate the fluoride (F) concentrations in whole, defatted and chocolate milks commercially available in Brazil and to estimate the daily F intake from these sources.Material and Methods:F concentrations were determined for 23 brands of milks, after HMDS-facilitated diffusion, using a F ion-specific electrode. Possible F ingestion per kg body weight was estimated, based on suggested volumes of formula consumption, for infants aging 1 to 12 months.Results:F concentrations ranged from 0.02 to 1.6 μg/mL F for all brands analyzed. Whole and defatted milks had the lowest F concentrations, ranging from 0.02 to 0.07 μg/mL. With respect to chocolate milks, three brands had F concentrations above 0.5 μg/mL. Some brands of chocolate milks exceeded the dose regarded as the threshold level for the development of dental fluorosis, without taking into account other sources of fluoride intake.Conclusion:The high fluoride concentrations found in some brands of chocolate milks in the present study indicate that many products may be important contributors to the total fluoride intake, reinforcing the need of assaying fluoride content of foods and beverages consumed by small children.

BackgroundDental erosion is caused by frequent exposure to acids without the involvement of microorganism. This study analyzed the effect of biguanides (polyhexamethylene biguanide – PHMB and chlorhexidine – CHX) on dentin erosion due to their possible influence on the enzymatic degradation of the demineralized organic matrix.MethodSixty bovine dentin specimens were prepared. On both sides of their surface, nail varnish was applied to maintain the reference surfaces for the determination of dentin loss. Samples were cyclically de- and remineralized for 6 days. Demineralization was performed with a 0.87 M citric acid solution (6×5 min daily). Thereafter, samples were treated with distilled water (negative control), 0.12% CHX (positive control), 0.07% PHMB, Sanifill Perio Premium™ (0.07% PHMB plus 0.05% NaF), or F solution (0.05% NaF) for 1 min and then subjected to enzymatic challenge for 10 min using a bacterial collagenase (Clostridium hystoliticum, 100 μg/ml). Dentin loss was assessed using profilometry (μm) daily. Data were analyzed using 2-way repeated measures-ANOVA and Bonferroni’s test (p < 0.05).ResultsDentin loss progressed significantly for all groups during the 6 days. After the 3rd day, Sanifill Premium™, CHX, and PHMB significantly reduced dentin erosion compared to control. On the 6th day, the lowest mean (±SD) dentin loss was observed for Sanifill Perio Premium™ (94.4 ± 3.9 μm). PHMB and CHX led to intermediate dentin loss (129.9 ± 41.2 and 135.3 ± 33.5 μm, respectively) that was significantly lower than those found for negative control (168.2 ± 6.2 μm). F (157.4 ± 6.1 μm) did not significantly differ from negative control.ConclusionsSanifill Perio Premium™ mouthwash has a good potential to reduce dentin loss, which might be associated with the presence of PHMB.

Background/Aims: There are still uncertainties regarding the use of whole and parotid ductal saliva as indicators of chronic exposure to fluoride. This study evaluated the effect of water fluoride concentration, age, gender, geographical area and localization (urban/rural) on fluoride concentrations in whole and ductal saliva. Methods: Subjects (n = 300) aged 3–7, 14–20, 30–40 and 50–60 years, from five communities (A–E) with different fluoride concentrations in the drinking water, participated in the study. Two samples of drinking water and parotid and whole saliva were collected for each subject and were analyzed for fluoride using appropriate electrode techniques. Results: Mean water F concentrations (±SE, mg/l, n = 60) were 0.09 ± 0.01, 0.15 ± 0.01, 0.66 ± 0.01, 0.72 ± 0.02, and 1.68 ± 0.08 for A–E, respectively. Mean F concentrations (±SE, mg/l, n = 15) ranged between 0.014 ± 0.002 (A, 3–7 years) and 0.297 ± 0.057 (D, 14–20 years) for whole saliva and 0.009 ± 0.001 (C, 30–40 years) and 0.284 ± 0.038 (E, 50–60 years) for parotid saliva. Results of multivariate linear regression analysis showed that geographical area and water fluoride concentration exerted the strongest influence in whole and ductal saliva F concentrations, respectively. Conclusion: Therefore, parotid ductal saliva seems to be a more appropriate biomarker of fluoride exposure, and factors like age and localization should also be considered when using this biomarker.

The aim of this study was to test the hypothesis of differences in performance including differences in ST-T wave changes between healthy men and women submitted to an exercise stress test. Two hundred (45.4%) men and 241 (54.6%) women (mean age: 38.7 ± 11.0 years) were submitted to an exercise stress test. Physiologic and electrocardiographic variables were compared by the Student t-test and the chi-square test. To test the hypothesis of differences in ST-segment changes, data were ranked with functional models based on weighted least squares. To evaluate the influence of gender and age on the diagnosis of ST-segment abnormality, a logistic model was adjusted; P < 0.05 was considered to be significant. Rate-pressure product, duration of exercise and estimated functional capacity were higher in men (P < 0.05). Sixteen (6.7%) women and 9 (4.5%) men demonstrated ST-segment upslope ≥0.15 mV or downslope ≥0.10 mV; the difference was not statistically significant. Age increase of one year added 4% to the chance of upsloping of segment ST ≥0.15 mV or downsloping of segment ST ≥0.1 mV (P = 0.03; risk ratio = 1.040, 95% confidence interval (CI) = 1.002-1.080). Heart rate recovery was higher in women (P < 0.05). The chance of women showing an increase of systolic blood pressure ≤30 mmHg was 85% higher (P = 0.01; risk ratio = 1.85, 95%CI = 1.1-3.05). No significant difference in the frequency of ST-T wave changes was observed between men and women. Other differences may be related to different physical conditioning

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Michelline e Carla, que apesar da distância, tenho a certeza de que mantêm o pensamento positivo em minha pessoa. Às amigas com as quais passei ótimos momentos em Bauru, no combate ao estresse do dia-a-dia: entre elas, Ana Cristina, Cinthia e Roberta. Aos amigos da 36ª Turma da FOB-USP. À amiga Juliane Carvalho, companheira para todos os momentos, pela amizade e apoio constante. Ju, muito obrigada de coração! Aos meus familiares que apoiaram com palavras de incentivo. A todos os voluntários participantes deste estudo, pela fundamental colaboração. À Associação Kagoshima do Brasil, que viabilizou um ano de experiência em pesquisa no Japão, e a Kagoshima University pelos ensinos adquiridos. Agradeço aos amigos da associação e a todos que criei durante a estada no Japão. À Japan International Cooperation Agency, pela oportunidade concedida de aperfeiçoar-me em pesquisa na The Nippon Dental University. Agradeço a todos do departamento de Patologia dessa unidade, em especial ao Prof. Dr. Aoba. Aos órgãos de fomento CAPES e em especial à FAPESP, pelo suporte financeiro que viabilizou este estudo científico. A todas as pessoas que, embora não citadas, de alguma forma colaboraram para a realização deste trabalho e concretização desta etapa importante em minha vida.