Navegando por Palavras-chave "Fluoride"
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- ItemSomente MetadadadosAbsence of DNA damage in multiple organs (blood, liver, kidney, thyroid gland and urinary bladder) after acute fluoride exposure in rats(Sage Publications Ltd, 2007-05-01) Leite, Aline de Lima; Santiago, Joel Ferreira; Levy, Flavia Mauad; Maria, Andrea Gutierrez; Fernandes, Mileni da Silva; Salvadori, Daisy Maria Favero; Ribeiro, Daniel Araki [UNIFESP]; Rabelo Buzalaf, Marflia Afonso; Universidade de São Paulo (USP); Univ Estadual Paulista; Universidade Federal de São Paulo (UNIFESP)Fluoride has been widely used in dentistry as a caries prophylactic agent. However, there has been some speculation that excess fluoride could cause an impact on genome integrity. in the current study, the potential DNA damage associated with exposure to fluoride was assessed in cells of blood, liver, kidney, thyroid gland and urinary bladder by the single cell gel (comet) assay. Male Wistar rats aging 75 days were distributed into seven groups: Groups 1 (control), 2, 3, 4, 5, 6 and 7 received 0 (deionized water), 10, 20, 40, 60, 80 and 100 mgF/Kg body weight from sodium fluoride (NaF), respectively, by gastrogavage. These groups were killed at 2 h after the administration of the fluoride doses. the level of DNA strand breaks did not increase in all organs evaluated and at all doses of NaF tested, as depicted by the mean tail moment. Taken together, our results suggest that oral exposure to NaF did not result in systemic genotoxic effect in multiple organs related to fluoride toxicity. Since DNA damage is an important step in events leading to carcinogenesis, this study represents a relevant contribution to the correct evaluation of the potential health risk associated with chemical exposure.
- ItemAcesso aberto (Open Access)O flúor pode ser considerado um agente genotóxico in vivo? Uma revisão sistemática(Universidade Federal de São Paulo, 2023-09-22) Drummond, Giovana Wagner Branda [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; http://lattes.cnpq.br/9969803499258672; Universidade Federal de São Paulo (UNIFESP)O objetivo deste estudo foi realizar uma revisão sistemática (RS) para investigar a literatura científica sobre os efeitos genotóxicos da exposição ao flúor (EF). As diretrizes do PRISMA-P foram utilizadas nesse cenário. A ferramenta PICOS (Participantes, Intervenção, Comparação, Desfecho e Desenho do estudo) adotou responder à seguinte questão: "O flúor pode ser considerado um agente químico genotóxico in vivo?" As bases de dados utilizadas para este estudo foi PubMed/Medline, SCOPUS e Web of Science. A qualidade dos estudos incluídos foi avaliada por meio do EPHP (Effective Public Health Practice Project). Um total de 20 estudos foram selecionados para avaliar a genotoxicidade induzida pelo flúor. 7 estudos demonstraram resultado positivo enquanto 13 estudos demonstraram resultados negativos. Após a revisão dos vinte estudos, 2 foram classificados como fracos, 4 foram considerados moderados e 14 foram considerados fortes, de acordo com a EPHPP. Dos 20 somente 16 estudos foram incluídos na metanálise devido a classificação como fraco e não descrição adequada de desvio padrão. A metanálise dos estudos de micronúcleos (MN) em fígado e medula óssea não mostrou diferença estatisticamente significativa (p=0,07). Nos estudos de troca de cromátides irmãs (ECS) em linfócitos também não diferiram estatisticamente significativamente (p=0,80). Para o ensaio de cometa (SCGEA), os estudos revelaram diferença estatisticamente significante com F em relação ao controle nos rins (SMD=2.09, 95% CI, 0.74 to 3.45, p<0.001), com Tau2=1,44; Chi2=566,38 e p=0,002, de modo que os estudos selecionados foram considerados heterogêneos e o I² de 87% indicou alta heterogeneidade. Em conjunto, foi estabelecido que a genotoxicidade do flúor é limitada e dose dependente.
- ItemSomente MetadadadosFluoride Induces Apoptosis in Mammalian Cells: In Vitro and In Vivo Studies(Int Inst Anticancer Research, 2017) Ribeiro, Daniel Araki [UNIFESP]; Cardoso, Caroline Margonato [UNIFESP]; Yujra, Veronica Quispe [UNIFESP]; Viana, Milena de Barros [UNIFESP]; Aguiar, Odair [UNIFESP]; Pisani, Luciana Pellegrini [UNIFESP]; Oshima, Celina Tizuko Fujiyama [UNIFESP]Apoptosis is genetically programmed cell death, an irreversible process of cell senescence with characteristic features different from other cellular mechanisms of death such as necrosis. In the last years, apoptosis has been extensively studied in the scientific literature, because it has been established that apoptosis plays a crucial role following the time course of chronic degenerative diseases, such as cancer. Thus, several researchers have strugged to detect what chemical agents are able to inter fere with the apoptotic process. Thus, the purpose of this literature review is to assess if fluoride induces apoptosis in mammalian cells using in vivo and in vitro test systems. Certain mammalian cell types such as oral cells, blood and brain were exetensively investigated
- ItemSomente MetadadadosPutative mechanisms of genotoxicity induced by fluoride: a comprehensive review(Springer Heidelberg, 2017) Ribeiro, Daniel Araki [UNIFESP]; Yujra, Veronica Quispe [UNIFESP]; Silva, Victor Hugo Pereira da [UNIFESP]; Claudio, Samuel Rangel [UNIFESP]; Estadella, Debora [UNIFESP]; Viana, Milena de Barros [UNIFESP]; Oshima, Celina Tizuko Fujiyama [UNIFESP]Genotoxicity is the ability of an agent to produce damage on the DNA molecule. Considering the strong evidence for a relationship between genetic damage and carcinogenesis, to elucidate the putative mechanisms of genotoxicity induced by fluoride are important to measure the degree of risk involved to human populations. The purpose of this article is to provide a comprehensive review on genotoxicity induced by fluoride on the basis of its mechanisms of action. In the last 10 years, all published data showed some evidence related to genotoxicity, which is due to mitochondrial disruption, oxidative stress, and cell cycle disturbances. However, this is an area that still requires a lot of investigation since the published data are not sufficient for clarifying the genotoxicity induced by fluoride. Certainly, the new information will be added to those already established for regulatory purposes as a safe way to promote oral healthcare and prevent oral carcinogenesis.
- ItemSomente MetadadadosThe role of fluoride on the process of titanium corrosion in oral cavity(Springer, 2012-10-01) Noguti, Juliana [UNIFESP]; De Oliveira, Flavia [UNIFESP]; Peres, Rogerio Correa; Renno, Ana Claudia Muniz [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Univ Monte Serrat; Santos Catholic UnivTitanium is known to possess excellent biocompatibility as a result of corrosion resistance, lack of allergenicity when compared with many other metals. Fluoride is well known as a specific and effective caries prophylactic agent and its systemic application has been recommended widely over recent decades. Nevertheless, high fluoride concentrations impair the corrosion resistance of titanium. the purpose of this article is to summarize the current data regarding the influence of fluoride on titanium corrosion process in the last 5 years. These data demonstrate noxious effects induced by high fluoride concentration as well as low pH in the oral cavity. Therefore, such conditions should be considered when prophylactic actions are administrated in patients containing titanium implants or other dental devices.
- ItemSomente MetadadadosUltrastructural morphometric analysis of ameloblasts exposed to fluoride during tooth development(Springer, 2006-11-01) Ribeiro, Daniel Araki [UNIFESP]; Hirota, Luciane; Cestari, Tania Mary; Ceolin, Daniele Santi; Taga, Rumio; Assis, Gerson Francisco de; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)Since a considerable amount of the world population is exposed to high doses of fluoride, it is of special concern to investigate its action mechanisms during dental enamel development. in this study, the toxicity of fluoride in ameloblasts during enamel development was evaluated by means of ultrastructural morphometric analysis. A total of 18 male Wistar rats were distributed into three groups. in Group I, the animals received deionized drinking water ad libitum (negative control) and in Groups II and III, they received sodium fluorided (NaF) drinking water at doses of 7 and 100 ppm ad libitum, respectively, for 6 weeks. Morphometric data were expressed as volume density of the most significant organelles present in the secretory and maturation phases of amelogenesis such as RER, granules, lysosomes, phagic vacuoles, microfilaments and mitochondria. the results showed that the volume density of mitochondria in the 100 ppm experimental group was 29% (P < 0.05) higher than the control group in secretory ameloblasts. No remarkable differences were found in maturation ameloblasts for all organelles evaluated. Taken together, these data indicate that NaF at high doses is able to induce cellular damage in secretory ameloblasts, whereas no noxious effect was observed during maturation stage of amelogenesis as depicted by ultrastructural analysis.