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1.
Arh Hig Rada Toksikol ; 73(3): 207-222, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36226821

ABSTRACT

This study aimed to investigate the effect of 150 mg/L sodium fluoride (NaF) on redox status parameters and essential metals [copper (Cu), iron (Fe), and zinc (Zn)] in the blood, liver, kidney, brain, and spleen of Wistar rats and to determine the protective potential of selenium (Se) against fluoride (F-) toxicity. Male Wistar rats were randomly distributed in groups of five (n=5) receiving tap water (control) or water with NaF 150 mg/L, NaF 150 mg/L + Se 1.5 mg/L, and Se 1.5 mg/L solutions ad libitum for 28 days. Fluorides caused an imbalance in the redox and biometal (Cu, Fe, and Zn) status, leading to high superoxide anion (O2 .-) and malondialdehyde (MDA) levels in the blood and brain and a drop in superoxide dismutase (SOD1) activity in the liver and its increase in the brain and kidneys. Se given with NaF improved MDA, SOD1, and O2 .- in the blood, brain, and kidneys, while alone it decreased SH group levels in the liver and kidney. Biometals both reduced and increased F- toxicity. Further research is needed before Se should be considered as a promising strategy for mitigating F- toxicity.


Subject(s)
Selenium , Trace Elements , Animals , Copper , Fluorides/pharmacology , Iron , Male , Malondialdehyde/pharmacology , Oxidation-Reduction , Oxidative Stress , Rats , Rats, Wistar , Sodium Fluoride/toxicity , Superoxide Dismutase/metabolism , Superoxide Dismutase/pharmacology , Superoxide Dismutase-1/pharmacology , Superoxides/pharmacology , Water , Zinc
2.
ACS Appl Mater Interfaces ; 9(22): 18774-18781, 2017 Jun 07.
Article in English | MEDLINE | ID: mdl-28497684

ABSTRACT

Ternary cobalt nickel sulfide as a novel and efficient electrode material in supercapacitors has recently gained extensive interests. Herein, we first report a highly conductive caterpillar-like NiCo2S4, composed of NiCo2S4 nanosheet core and nanowire shell grown on Ni foam via a facile and cost-effective chemical liquid process. Growth mechanism of the NiCo2S4 nanosheets@nanowires (NSNWs) structure was also investigated in detail by analyzing time-dependent experimental as well as the amount of additive ammonium fluoride in solution. Furthermore, the electrochemical measurements were performed among three different morphologies of NiCo2S4 including nanosheets, nanosheets@nanoparticles, and NSNWs structure, which were obtained from different reaction stages. Because the NSNWs structure has relatively high electroactive surface area, conductivity, and effective electron transport pathways, the as-prepared NiCo2S4 NSNWs structure comparing with two other morphologies exhibits the maximum specific capacity of 1777 F/g at 1 A/g and the highest capacitance retention (83% after 3000 cycles) at a high scan rate of 10 A/g with a mass loading density of 4.0 mg/cm2. These results indicate that the NiCo2S4 NSNWs structure has great potential in supercapacitors.

3.
Nanoscale Res Lett ; 10(1): 441, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26573932

ABSTRACT

The applications of zinc oxide (ZnO) nanowires (NWs) in implantable wireless devices, such as diagnostic nanobiosensors and nanobiogenerators, have recently attracted enormous attention due to their unique properties. However, for these implantable nanodevices, the biocompatibility and the ability to control the behaviour of cells in contact with ZnO NWs are demanded for the success of these implantable devices, but to date, only a few contrasting results from their biocompatibility can be found. There is a need for more research about the biocompatibility of ZnO nanostructures and the adhesion and viability of cells on the surface of ZnO nanostructures. Here, we introduce synthesis of a new nature-inspired nanostructured ZnO urchin, with the dimensions of the ZnO urchin's acicula being controllable. To examine the biocompatibility and behaviour of cells in contact with the ZnO urchin, the Madin-Darby canine kidney (MDCK) epithelial cell line was chosen as an in vitro experimental model. The results of the viability assay indicated that, compared to control, the number of viable cells attached to the surface of the ZnO urchin and its surrounding area were reduced. The measurements of the Zn contents of cell media confirmed ZnO dissolution, which suggests that the ZnO dissolution in cell culture medium could lead to cytotoxicity. A purposeful reduction of ZnO cytotoxicity was achieved by surface coating of the ZnO urchin with poly(vinylidene fluorid-co-hexafluoropropylene) (PVDF-HFP), which changed the material matrix to slow the Zn ion release and consequently reduce the cytotoxicity of the ZnO urchin without reducing its functionality.

4.
Rev. odonto ciênc ; 27(2): 166-169, 2012. ilus
Article in English | LILACS, BBO - Dentistry | ID: lil-649744

ABSTRACT

PURPOSE: To report a case of florid cemento-osseous dysplasia (FCOD) and chronic diffuse sclerosing osteomyelitis (CDSO) in a simultaneous presentation, emphasizing the significance of differential diagnosis and appropriate management of these conditions. CASE DESCRIPTION: A female, 69 years old, black patient had a complaint of itching and pain in posterior left mandibular region. The patient had a yellowish hard mass throughout all quadrants of the jaws. A panoramic radiograph showed a lobular, diffuse and irregular radiopaque lesion. Based on clinical and histopathological findings, the diagnosis was FCOD associated with secondary osteomyelitis. CONCLUSION: This report reinforces the need of accurate assessment of clinical, radiographic and histopathological aspects for the diagnosis and correct selection of treatment in cases of combined lesions.


OBJETIVO: relatar um caso de displasia cemento-óssea florida (DCOF) e osteomielite esclerosante difusa crônica (OEDC) em uma apresentação simultânea, enfatizando a importância do diagnóstico diferencial e adequado manejo dessas condições. DESCRIÇÃO DO CASO: Uma paciente do sexo feminino, 69 anos de idade, de cor negra, tinha uma queixa de dor e coceira na região esquerda da mandíbula. A paciente apresentava uma massa dura amarelada envolvendo todos os quadrantes dos maxilares. Foi obtida uma radiografia panorâmica, revelando lesão radiopaca lobular, difusa e irregular. Com base nos aspectos clínicos e histopatológicos, o diagnóstico foi de DCOF associada com osteomielite secundária. CONCLUSÃO: esse relato reforça a necessidade de uma avaliação precisa dos aspectos clínicos, radiográficos e histopatológicos para o diagnóstico e seleção correta de tratamento em casos de lesões combinadas.


Subject(s)
Humans , Female , Aged , Bone Diseases, Developmental , Osteomyelitis
5.
Bauru; s.n; 2010. 239 p. ilus, tab, graf.
Thesis in Portuguese | BBO - Dentistry | ID: biblio-865276

ABSTRACT

O processo de reparo do tecido ósseo tem sido alvo de estudos com o intuito de promover uma melhora na qualidade e tempo de reparo. Um elemento que tem sido estudado por alguns grupos é o fluoreto, pois tem sido proposto como terapêutico para osteoporose (Europa). Deste modo, o objetivo deste trabalho foi avaliar comparativamente o efeito do fluoreto administrado na água de beber sobre o reparo ósseo alveolar de ratos. Neste estudo foram utilizados 4 grupos com ratos Wistar de 80 dias de vida (n=200), os quais receberam água de beber contendo 5, 15 e 50 ppm de fluoreto e água deionizada (controle) durante todo experimento. Esses animais tiveram o incisivo superior direito extraído. Os animais foram eutanasiados 0 hora, 7, 14, 21 e 30 e 60 dias após a extração. Amostras de plasma sanguíneo foram obtidas para análise de concentração de flúor, e a região do alvéolo dental foi coletada para as análises de microscopia (Hematoxilina Eosina e imunoistoquímica) e zimografia (metaloproteinases de matriz 2 e 9 MMP-2 e 9). A análise de concentração de flúor no plasma sangüíneo mostrou maior presença desse elemento no grupo tratado com 50 ppm de F nos períodos de 21 e 30 dias. Na análise histológica foi detectado osso neoformado em todos os animais até 60 dias, porém o grupo de 50 ppm de F apresentou menor formação óssea nos períodos de 14, 21 e 30dias. A análise morfométrica confirmou um aumento na densidade de volume de osso neoformado, entre 7 e 60 dias, nos grupos controle, 5 ppm, 15 ppm e 50 ppm de F, com concomitante diminuição na densidade de volume de coágulo sangüíneo. A expressão de RANK-L e OPG não foi alterada pela exposição crônica ao fluoreto na água de beber durante os períodos estudados (p<0,05). A atividade da MMP-2 foi mais acentuada no período inicial, enquanto a MMP-9 teve maior atividade no período final. Concluiu-se que o F, em altas concentrações pode alterar a dinâmica do reparo ósseo alveolar diminuindo a formação de novo tecido ósseo, associado...


The repair of bone has been investigated with the aim of promoting an improvement in the quality and time of the repair process. One element that has been studied by some groups is fluoride, it has been proposed as a treatment for osteoporosis (Europe). Thus, the objective was to comparatively evaluate the effect of fluoride administered in drinking water on alveolar bone repair in rats. This study used 4 groups of rats of 80 days (n=200), which received drinking water containing 5, 15, and 50 ppm of fluoride, and deionized water (control) throughout the experiment. These animals had their upper right incisor extracted. The animals were euthanized 0 hours, 7, 14, 21 and 30 and 60 days after extraction. Samples of blood plasma were obtained for analysis of fluoride concentration, and the region of the alveolus was collected for microscopic analysis (Hematoxylin eosin and Immunohistochemistry) and zymography (metalloproteinases 2 and 9 MMP-2 and 9). Analysis of fluoride concentration in blood plasma showed a greater presence of this element in the group treated with 50 ppm of F in periods of 21 and 30 days. Histological analysis detected a new bone formed in all animals up to 60 days, but the group of 50 ppm F showed lower bone formation at 14, 21 and 30 days. Morphometric analysis confirmed an increase in the volume density of newly formed bone, between 7 and 60 days in control groups, 5 ppm, 15 ppm and 50 ppm F, with a concomitant decrease in the volume density of blood clot. The expression of RANK-L and OPG was not altered by chronic exposure to fluoride in drinking water during the study period (p<0.05). The activity of MMP-2 was more pronounced in the early period, while MMP-9 had higher activity in the final period. It was conclude that the F, in high concentrations change the dynamics of the alveolar bone repair by decreasing the formation of new bone, associated with a delay in treating the blood clot. Proteins as RNK-L, OPG, MMP-2 and MMP-9 may also...


Subject(s)
Animals , Male , Rats , Tooth Socket , Bone Resorption , Fluorides/metabolism , Bone Regeneration , Analysis of Variance , Tumor Necrosis Factors/analysis , Fluorides/analysis , Fluorides/blood , Matrix Metalloproteinases , Rats, Wistar , Statistics, Nonparametric , Time Factors
6.
J. appl. oral sci ; 17(5): 495-500, Sept.-Oct. 2009. ilus, graf, tab
Article in English | LILACS | ID: lil-531403

ABSTRACT

OBJECTIVE: The objective of this study was to evaluate the effect of desensitizing agents containing different amounts of fluoride on the shear bond strength of a dual polymerized resin cement and a resin-modified glass ionomer cement (RMGIC) to dentin. MATERIAL AND METHODS: One hundred human molars were mounted in acrylic resin blocks and prepared until the dentin surface was exposed. The specimens were treated with one of four desensitizing agents: Bifluorid 12, Fluoridin, Thermoline and PrepEze. The remaining 20 specimens served as untreated controls. All groups were further divided into 2 subgroups in which a dual polymerized resin cement (Bifix QM) or a resin-modified glass ionomer cement (AVANTO) was used. The shear bond strength (MPa) was measured using a universal testing machine at a 0.5 mm/min crosshead speed. The data were analyzed statistically with a 2-way ANOVA, Tukey HSD test and regression analysis (α=0.05). The effect of the desensitizing agents on the dentin surface was examined by scanning electron microscopy. RESULTS: The fluoride-containing desensitizing agents affected the bond strength of the resin-based cements to dentin (p<0.001). PrepEze showed the highest bond strength values in all groups (p<0.001). CONCLUSION: Regression analysis showed a reverse relation between bond strength values of resin cements to dentin and the amount of fluoride in the desensitizing agent (p<0.05).


Subject(s)
Humans , Cariostatic Agents/chemistry , Dental Bonding , Dentin Desensitizing Agents/chemistry , Dentin-Bonding Agents/chemistry , Dentin/ultrastructure , Fluorides/chemistry , Resin Cements/chemistry , Adhesiveness , Calcium Fluoride/chemistry , Composite Resins/chemistry , Dental Stress Analysis/instrumentation , Fluorides, Topical/chemistry , Glass Ionomer Cements/chemistry , Materials Testing , Microscopy, Electron, Scanning , Shear Strength , Stress, Mechanical , Sodium Fluoride/chemistry , Temperature , Time Factors , Water/chemistry
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