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OBJECTIVE: To evaluate the effect of fluoride consistency and composition to protect enamel and dentin against the dental erosion. MATERIALS AND METHODS: Bovine enamel and dentin specimens were treated with artificial saliva, neutral fluoride gel (NFG), acidulated phosphate fluoride gel (AFG), neutral fluoride foam (NFF), and acidulated phosphate fluoride foam. The samples were subjected to cycling. Micro energy-dispersive X-ray fluorescence spectrometry, surface roughness (Ra), contact angle (CA), and scanning electron microscopy (SEM) were performed. Composition, CA and Ra data were analyzed by ANOVA and multiple comparison test (p < 0.05). RESULTS: The dentin protected had a significantly higher mineral content than in the control. Eroded unprotected enamel had higher Ra values than normal surfaces. Fluoride treatments increased the Ra in dentin samples. AFG increased the CA in enamel. Fluoride foams increased CA in dentin with reduced mineral loss. SEM analysis found a deposited layer on enamel treated with AFG and remnants of deposits on dentin treated with NFG and NFF. CONCLUSION: Regardless of the form of application, fluoride provided protection against erosion, however with different levels. CLINICAL SIGNIFICANCE: Applying the adequate fluoride form is relevant since the formulations have different effects on both enamel and dentin.

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BACKGROUND: Understanding the elements that support cataract development and searching for available therapeutic methods is essential for scientific and social interest. For that purpose, the role of trace elements has been investigated in this study to better understand the development of cataracts in dogs. OBJECTIVE: The aim of this study was to evaluate the ratio of the major and trace elements by X-ray fluorescence spectrometry in dog cataract lenses to contribute to diagnostic, non-surgical, and ophthalmological preventive data. METHODS: A single lens with a cataract from each of a total of 88 dogs (cataract group) and a healthy lens from each of 6 dogs (control group) were evaluated. The elements calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), magnesium (Mg), manganese (Mn), and potassium (K) were analyzed by energy dispersive X-ray fluorescence and X-ray microfluorescence. RESULTS: The results indicated an increase of Ca, Fe, Cu, and Zn, in association with the reabsorption mechanism of hypermature cataracts. CONCLUSIONS: The ratio of elements Ca, Fe, Cu, and Zn was different in cataract lenses than in healthy lenses, and our results may support the development of therapeutic strategies for cataracts in dogs. The Ca concentrations were distinct in the cataract development stages, and the Fe concentration was relatively higher in males when compared to females. Finally, this research stands out with a particular contribution to the understanding of both cataract formation and prevention.

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Laminitis is a disease that affects the dermis and epidermis of the bovine hoof, generating changes in the hoof capsule. This study evaluated the effects of clinical laminitis diagnosed after the adaptation phase to confinement on the morphology, density, and mineral composition of the hoof of Nellore cattle after finishing. The animals were separated in the first weeks of confinement into a sick group (SG), with clinical laminitis, and a healthy group (HG). SG animals had higher heel length, dorsal wall length, toe height, and diagonal hoof length (p<0.05) than healthy animals. The dermal laminae had similar measurements for thickness, length, and spacing between them between SG and HG. Animals with laminitis showed congestion, hemorrhage, and basement membrane irregularities on histology. Computed microtomography (µCT) revealed that the hoof density of sick animals is lower than healthy ones. According to the mineral composition by energy-dispersive X-ray fluorescence (ED-XRF) spectrometry, the hooves of animals with laminitis (SG) and healthy ones (HG) were not biochemically different. Therefore, the occurrence of clinical laminitis in Nellore cattle in the first weeks of confinement causes an increase in the morphometric parameters of the hoof capsule and a reduction in the density of the abaxial hoof wall evaluated after the finishing period. This disease does not promote changes in the histomorphometric parameters of the dermal laminae and the percentage of minerals in the abaxial hoof wall.

A laminite é uma doença que afeta a derme e epiderme do casco de bovinos gerando alterações no estojo córneo. O estudo avaliou os efeitos da laminite clínica diagnosticada após a fase de adaptação ao confinamento na morfologia, densidade e composição mineral do casco de bovinos da raça Nelore após terminação. Nas primeiras semanas de confinamento, os animais foram separados em um grupo doente (GD) com laminite clínica e em um grupo saudável (GS). Os animais do GD apresentaram maior comprimento de talão, comprimento da parede dorsal, altura da pinça e comprimento diagonal do casco (p<0,05) do que os saudáveis. As lâminas dérmicas tiveram medidas semelhantes para espessura, comprimento e espaçamento entre elas entre GD e GS. Animais doentes apresentaram congestão, hemorragia e irregularidades da membrana basal na histologia. A microtomografia computadorizada (µCT) revelou que a densidade do casco de animais doentes é menor do que o saudável. Para a composição mineral por meio da espectrometria de fluorescência de raio-X por dispersão de energia (ED-XRF), o casco dos animais doentes (GD) e dos saudáveis (GS), não se mostraram diferentes bioquimicamente. Conclui-se que a ocorrência de laminite clínica em bovinos da raça Nelore nas primeiras semanas de confinamento ocasiona aumento de parâmetros morfométricos do estojo córneo e redução da densidade da parede abaxial do casco, avaliados após o período de terminação. Essa enfermidade não promove modificações nos parâmetros histomorfométricos das lâminas dérmicas e na porcentagem de minerais da parede abaxial do casco.

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ABSTRACT Wood is a renewable material considered eco-friendly and used for various purposes. While wood treated with chromated copper arsenate (CCA) does not deteriorate, its final disposal may entail risks due to the concentration and toxicity of the components. The removal of CCA from wood can be achieved in different ways. This study focuses on the reduction of the concentrations of Cu, Cr, and As chemical species by the electro-removal technique, aiming to obtain biomass with low deleterious potential that would allow multiple uses or safe disposal in landfills. The analytical results showed reductions of 79.5, 87.4, and 81.3% in the mean concentrations of Cu, Cr, and As, respectively. It is worth mentioning the occurrence of the fungus Xylaria sp. after treatment 6 (60 min, 5 g, and 25 V), further suggesting that the method was effective. Samples of these fungi were identified from isolates by culture in medium, DNA extraction, and sequencing of the Internal Transcribed Spacer (ITS) region.

RESUMO A madeira é um material renovável, considerado ecologicamente correto e utilizado para diversos fins. Embora a madeira tratada com arseniato de cobre cromado (CCA) não se deteriore facilmente, seu descarte final pode acarretar riscos devido à concentração e toxicidade dos componentes. A remoção do CCA da madeira pode ser realizada de diferentes maneiras. Este estudo teve como foco a redução das concentrações de espécies químicas Cu, Cr e As pela técnica de eletro-remoção, visando obter uma biomassa com baixo potencial deletério que permitiria múltiplos usos ou disposição final segura em aterros sanitários. Os resultados analíticos mostraram reduções de 79,5; 87,4 e 81,3% nas concentrações médias de Cu, Cr e As, respectivamente. Vale ressaltar a ocorrência do fungo Xylaria sp. após o tratamento 6 (60 min, 5 g e 25 V), sugerindo ainda que o método foi eficaz. Amostras desses fungos foram identificadas dos isolados por meio de cultura em meio, extração de DNA e sequenciamento da região do espaçador transcrito interno (ITS).

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A method was developed based on reversed-phase vortex-assisted liquid-liquid microextraction (RP-VALLME) combined with energy dispersive X-ray fluorescence (EDXRF) spectrometry for the determination of Cu, Mn, Ni, and Pb in diesel oil samples. In this procedure, a nitric acid solution was used as the extraction phase to isolate analytes from organic samples. After a centrifugation step, the aqueous phase was added dropwise to a filter paper disc for EDXRF determinations. The following variables were optimized: type of extraction phase solution, concentration of the extraction phase, stirring time, and sample volume. Some instrumental parameters were also evaluated: atmospheric condition, irradiation energy, and irradiation time. Using 100 µL of a 0.075 mol L-1 nitric acid solution as the extraction phase for a sample volume of 5.0 mL and a stirring time of 45 s, the limits of detection were 14, 8, 10, and 7 µg L-1 for Cu, Mn, Ni, and Pb, respectively. The enrichment factors obtained were 34 (Cu), 62 (Mn), 59 (Ni), and 64 (Pb). The precisions, expressed as relative standard deviations (RSDs, %), were calculated from ten replications of the experiment under optimized conditions using standard solutions containing 200 µg L-1 and 400 µg L-1 of all four analytes and ranged between 2.1 and 6.4%. The results of recovery tests ranged from 87 to 112%. The proposed procedure was efficiently applied to the determination of the four analytes in diesel oil samples. The results were compared with those obtained by inductively coupled plasma optical emission spectrometry (ICP-OES) after sample digestion, and no significant differences were found.

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This study evaluated the antierosive effect applying a modified acidulated phosphate fluoride (APF) gel containing nano-hydroxyapatite (nHAp) on the enamel surface before erosion. After polishing, the exposed flat enamel surfaces (n = 7/group) from bovine incisors were treated with artificial saliva (S - negative control), orange juice (ERO), APF gel (positive control) and APF_nHAp gel. All samples were subjected to six cycles of demineralization (orange juice, pH ~ 3.5, 10 min) followed by remineralization (saliva, 37°C, 1 hr). The enamel surface morphology, topography, and inorganic composition were analyzed using scanning electron microscopy, roughness testing, and micro energy-dispersive X-ray fluorescence spectrometry, respectively. The mean (standard deviation) roughness values (Ra, µm) were S, 0.13 (0.05); ERO, 0.25 (0.07); APF, 0.22 (0.08); and APF_nHAp, 0.17 (0.04). Ra values were significantly higher after ERO (p < .01) and APF (p < .05) treatments than after S. The enamel surface morphology was altered by the treatments, except for the S specimens. The mineral content of the enamel showed a clear trend with Ca and P reduction in the order of APF < S < APF_nHAp < ERO and APF < S < ERO < APF_nHAp, respectively. We can conclude that APF gel increased mineral concentration on the enamel. Moreover, the APF_nHAp material modified the composition and morphology of the enamel surface.

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OBJECTIVES: The effects of fluoride treatment on bovine enamel subjected to acid erosion were studied by roughness (Ra) measurements, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and microenergy-dispersive X-ray fluorescence spectrometry (µ-EDXRF). MATERIALS AND METHOD: Enamel samples (63) were divided into nine groups (n = 7): artificial saliva (AS), Pepsi Twist(®) (PT), orange juice (OJ), Duraphat(®) + Pepsi Twist(®) (DPH/PT), Duraphat(®) + orange juice (DPH/OJ), Duofluorid(®) + Pepsi Twist(®) (DUO/PT), Duofluorid(®) + orange juice (DUO/OJ), fluoride gel + Pepsi Twist(®) (FG/PT), and fluoride gel + orange juice (FG/OJ). Fluoride was applied and the samples were submitted to six cycles (demineralization: Pepsi Twist(®) or orange juice, 10 min; remineralization: saliva, 1 h). The enamel surface in depth was exposed and 63 line-scan maps were performed. RESULTS: The elemental analysis by EDS revealed that only fluoride treated groups had any detectable fluorine after erosion cycles (DPH/PT: 3.50 wt%; DPH/OJ: 3.37 wt%; DUO/PT: 2.69 wt%; DUO/OJ: 3.54 wt%; FG/PT: 2.17 wt%; FG/OJ: 2.77 wt%). PT treatment resulted in significantly higher Ra values than the artificial saliva (P < 0.001). Scanning electron microscopy (SEM) analysis of fluoride protected enamel showed areas with some globular structures or a residual layer of varnish. The enamel thickness was significantly lower in PT (0.63 ± 0.087 mm) than in DPH/PT (0.87 ± 0.16 mm) and DUO/PT (0.92 ± 0.14 mm) groups (P < 0.01). CLINICAL RELEVANCE: Fluoride treatments protected enamel without Ra increase and loss of enamel tissue.

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The aim of this study was to investigate the effects of some acidic drinks on dentin erosion, using methods of surface profile (SP) analysis and energy-dispersive X-ray fluorescence spectrometry (EDXRF). One hundred standardized dentin slabs obtained from bovine incisor roots were used. Dentin slabs measuring 5x5 mm were ground flat, polished and half of each specimen surface was protected with nail polish. For 60 min, the dentin surfaces were immersed in 50 mL of 5 different drinks (Gatorade®, Del Valle Mais orange juice®, Coca-Cola®, Red Bull® and white wine), 20 blocks in each drink. The pH of each beverage was measured. After the erosive challenge, the nail polish was removed and SP was analyzed. The mineral concentration of dentin surfaces was determined by means of EDXRF. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). SP analysis showed that Red-Bull had the highest erosive potential (p<0.05). EDXRF results exhibited a decrease in phosphate in the groups immersed in Red-Bull, orange juice and white wine (p<0.05), and no significant difference in calcium content between the reference surface and eroded surface. In conclusion, this study demonstrated that all studied beverages promoted erosion on root dentin and Red Bull had the highest erosive potential. There was no correlation between pH of beverages and their erosive potential and only the P content changed after erosive challenge.

O objetivo deste estudo foi investigar os efeitos de algumas bebidas ácidas sobre a erosão da dentina, utilizando métodos de análise de perfil de superfície (SP) e espectrometria de energia dispersiva de fluorescência de raios X (EDXRF). Cem blocos de dentina padronizados obtidos de raízes de incisivos bovinos foram utilizados. Os blocos de dentina medindo 5x5 mm foram planificados, polidos e metade de cada superfície das amostras foram impermeabilizados com esmalte para unhas. Por 60 min, as superfícies de dentina foram imersas em 50 mL de 5 bebidas diferentes (Gatorade, suco de laranja, Coca-Cola, Red Bull e vinho branco), 20 blocos em cada bebida. O pH de cada bebida foi medido. Após o desafio erosivo, o esmalte de unha foi removido e SP foram analisados. A concentração de minerais das superfícies de dentina foi determinada por meio de EDXRF. Os dados foram analisados estatisticamente por ANOVA e teste de Tukey. (p<0,05). A análise SP mostrou que o Red-Bull apresentou o maior potencial erosivo. Os resultados do EDXRF apresentaram uma diminuição do fosfato dos grupos imersos no Red-Bull, suco de laranja e vinho branco, e não houve diferença significativa no teor de cálcio entre a superfície de referência e a superfície que sofreu erosão. O Red Bull apresentou o maior potencial erosivo sobre a dentina radicular. Não houve correlação entre o pH das bebidas e o seu potencial erosivo.

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