American tegumentary leishmaniasis: epidemiological and molecular characterization of prevalent Leishmania species in the State of Tocantins, Brazil, 2011-2015.

Determination of the epidemiological profile of the American tegumentary leishmaniasis (ATL) and identification of Leishmania species that are prevalent in the State of Tocantins were carried out through a retrospective and descriptive study based on data reported in SINAN, in the period from 2011 to 2015. Molecular techniques such as PCR-RFLP and PCR-G6PD to amplify Leishmania DNA were performed on stored on Giemsa-stained slides from lesion scarifications of ATL patients who were amastigote-positive by the direct microscopic examination. There were 1,434 ATL cases in Tocantins reported in this period. The highest incidence was reported in men aged over 60 years, rural residents, the most affected ethnic group was mixed ethnicity (mixed black and white) and the ones with lower education. The predominant clinical form was cutaneous, being diagnosed mainly by laboratory methods. Pentavalent antimonial was effective in resolving cases. The predominant species found in 271 analyzed samples from 32 municipalities located in 8 different health regions of Tocantins was Leishmania (Viannia) braziliensis. Identifying the epidemiological profile and characterizing the Leishmania spp species on regional level is essential to establish control and prevention behaviors, minimizing the number of cases and treatment resistance, recurrence and evolution to mucosal forms.

Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants.

OBJECTIVE:: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. METHODS:: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. RESULTS:: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. CONCLUSION:: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.

Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants

ABSTRACT Objective: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. Methods: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. Results: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. Conclusion: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.

RESUMO Objetivo: avaliar, in vitro, e comparar a citotoxicidade e a resistência à corrosão de mini-implantes de três marcas comerciais diferentes, utilizados para ancoragem ortodôntica. Métodos: seis mini-implantes fabricados pelas empresas Conexão(r), Neodent(r) e SIN(r) foram imersos, separadamente, em saliva artificial (pH = 6,76), por 30 e 60 dias, de forma a obter os extratos da corrosão. A citotoxicidade dos extratos foi avaliada em cultura de células L929, empregando-se a análise de ensaios do cristal violeta e MTT, bem como da morfologia celular sob microscopia óptica. As características da superfície do metal antes e após a imersão em saliva artificial foram avaliadas usando microscopia eletrônica de varredura. Os extratos foram submetidos a espectrofotometria de absorção atômica, para determinar as concentrações dos íons alumínio e vanádio, elementos constituintes da liga e que apresentam toxicidade em potencial. Para análise estatística, os testes one-way ANOVA/Bonferroni foram usados para comparação entre os grupos, com p < 0,05 sendo considerado significativo. A análise estatística foi realizada com o programa Graph Pad PRISM v. 4.0. Resultados: não foi observada alteração na viabilidade ou morfologia celular após a exposição dos mini-implantes aos extratos. A análise dos mini-implantes por microscopia eletrônica de varredura revelou superfícies lisas e sem traços evidentes de corrosão. Os extratos analisados usando espectrofotometria de absorção atômica apresentaram concentrações de íons alumínio e vanádio inferiores a 1,0 µg/ml e 0,5 µg/ml, respectivamente. Conclusão: os mini-implantes fabricados pelas empresas Conexão(r), Neodent(r) e SIN(r) apresentam alta resistência à corrosão e não são citotóxicos.