Experimental Medications for Using in Endodontics: Cytotoxicity, Genotoxicity and Mutagenesis Analysis / Medicamentos Experimentais para Uso em Endodontia: Análise de Citotoxicidade, Genotoxicidade E Mutagênese

The objective was to evaluate the cytotoxic, genotoxic and mutagenic properties of two experimental medication in Endodontics. For cytotoxic evaluation, fibroblast and osteoblast cells (1x104 cells/well) were plated and divided into groups conforming to the product added in culture medium: EM1 - 20 µL of experimental medication 1 (EM1); EM2 - 20 µL of experimental medication 2 (EM2); VE - 20 µL of vehicle used in medications; C - without product. The MTT assay was performed at 24, 48 e 72 hours for cytotoxic analysis. For genotoxic and mutagenic evaluation, 42 male rats were used. After 1 and 7 days of tubes containing EM1 or EM2, or empty (NC) were subcutaneously implanted, and after 1 day, a single dose of cyclophosphamide (CY) to be applied, the bone marrow was collected and submitted to comet and micronuclei assay. The significance level of 5% was considered for all statistical analysis. The viability of fibroblasts was <70% to both medications at 24h, and EM1 at 72h; at 72h, the proliferation cells was observed in EM2 (>100%). Both medications were non-cytotoxic to osteoblasts, and the EM2 stimulate the cell proliferation at 72h. The damage frequency of CY was statistically similar to EM1 and different to EM2 (p<0.05). The number of micronuclei was insignificant to EM1 and EM2 and no difference to group NC (p>0.05). Despite the absence of mutagenesis and non-cytotoxicity to osteoblasts, the EM1 was cytotoxic and genotoxic to fibroblasts. The EM2 was non-genotoxic, non-cytotoxic and nonmutagenic. (AU)

O objetivo foi avaliar as propriedades citotóxicas, genotóxicas e mutagênicas de dois medicamentos experimentais em Endodontia. Para avaliação citotóxica, células fibroblásticas e osteoblásticas (1x104 células/poço) foram plaqueadas e divididas em grupos de acordo com o produto adicionado no meio de cultura: EM1 - 20 µL da medicação experimental 1 (EM1); EM2 - 20 µL da medicação experimental 2 (EM2); VE - 20 µL de veículo utilizado em medicamentos; C ­ sem produto. O ensaio MTT foi realizado aos 24, 48 e 72 horas para análise citotóxica. Para avaliação genotóxica e mutagênica foram utilizados 42 ratos machos. Após 1 e 7 dias foram implantados por via subcutânea tubos contendo EM1 ou EM2, ou vazios (NC), e após 1 dia, foi aplicada dose única de ciclofosfamida (CY), a medula óssea foi coletada e submetida ao ensaio de cometa e micronúcleos. O nível de significância de 5% foi considerado para todas as análises estatísticas. A viabilidade dos fibroblastos foi <70% para ambas as medicações às 24h e ao EM1 às 72h; às 72h, a proliferação de células foi observada em EM2 (>100%). Ambas as medicações foram não citotóxicas para os osteoblastos, e o EM2 estimulou a proliferação celular às 72h. A frequência de dano do CY foi estatisticamente semelhante ao EM1 e diferente do EM2 (p<0,05). O número de micronúcleos foi insignificante para EM1 e EM2 e não houve diferença para o grupo NC (p>0,05). Apesar da ausência de mutagênese e não citotoxicidade para osteoblastos, o EM1 foi citotóxico e genotóxico para fibroblastos. O EM2 era não genotóxico, não citotóxico e não mutagênico. (AU)

Synergistic Antigenotoxic and Antioxidant Action of Gum Arabic and Eugenol in Rat Liver Following Induction of Colorectal Carcinogenesis.

OBJECTIVE: Much research has been conducted to identify natural antioxidant and antimutagenic compounds capable of preventing, reverting or treating conditions caused by oxidative stress and genotoxicity. In this study we evaluated the effects of 10% gum arabic (GA) and eugenol (EUG) on hepatic oxidative stress and genotoxicity induced by dimethylhydrazine (DMH) in rats. METHODS: The prevention arm of the study included 4 control groups and 4 experimental groups. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA , EUG or 10% GA + EUG  by gavage. The treatment arm of the study included 4 control groups and 4 experimental groups. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG  by gavage. Finally, the livers were harvested for histopathological study with HE, measurement of genotoxicity and oxidative stress. RESULT: Genotoxicity and oxidative stress were found to be significantly lower in Group XII (animals treated concomitantly with GA and EUG). This is the first study to observe the synergistic action of GA and EUG administered concomitantly in this scenario. CONCLUSION: Indicating a synergistic antigenotoxic and antioxidant effect on liver cells in rats with DMH-induced colorectal carcinogenesis.

Mutagenicity in oral cells of individuals exposed to radiofrequency generated by different smartphones

Aim: This study aimed to investigate whether non-ionizing radiation emitted by smartphones is likely to cause genotoxic effects on oral epithelial cells. Methods: Thirty adults were distributed into two groups according to the mobile phone brand used, namely Samsung (Samsung, Seoul, South Korea) and Apple (Apple, California, USA). The material was collected with gentle swabbing of the right and left buccal mucosa using a cervical brush, then the micronucleus test was performed. Results: The Mann-Whitney test with a 5% significance level did not reveal statistically significant differences in micronuclei frequency between the exposed and non-exposed sides (p=0.251). The different brands do not seem to cause risks of inducing genetic damage because there were no statistically significant differences between them (p=0.47). Conclusion: Therefore, our results suggest no correlations of micronuclei frequency in the exposed buccal cells of mobile phone users at the exposure standard levels observed

Assessment of genotoxicity of glass ionomer cements: a systematic review.

To evaluate, through a systematic review, the assessment of genotoxicity of glass ionomer cements in vitro and in vivo. A systematic review was performed with the problem, intervention, control, and outcomes (PICOS) strategy, aiming to answer the following question: "Can glass ionomer cements induce genetic damage in vitro and in vivo?" A systematic search was performed in the following electronic databases: PubMed (including MedLine), Web of Science, and Scopus. The quality of included studies was assessed using the Effective Public Health Practice Project (EPHPP). After the authors performed the review of all articles, a total of 13 manuscripts met all the inclusion criteria in the systematic review. Following the parameters of the EPHPP, eight articles were classified as strong or moderate quality. The other ones (five studies) were weak. Taken together our results demonstrated that, six studies reported genotoxicity of the modified glass ionomer cements tested and two studies concluded that the effect of genotoxicity was time dependent.

Can exposure to panoramic radiographs induce genotoxic effects on the oral epithelium? A systematic review with meta-analysis.

OBJECTIVE: To evaluate, through a systematic review (SR) with meta-analysis, the occurrence of genotoxic effects in the oral epithelium after the exposure of patients to panoramic radiographs. METHODS: An SR was performed with the PICOS (Population, Intervention, Comparison, Outcome, and Study design) strategy, aiming to answer the following question: "Can panoramic radiographs induce genotoxic effects on the oral epithelium?" The study was registered in the PROSPERO (International prospective register of systematic reviews) platform. A systematic search was performed in the following electronic databases: PubMed (including MedLine), Scopus, Embase, LILACS, Medline EbscoHost, and Google Scholar. Treatment effects were defined as standardized mean difference (SMD), and 95% confidence intervals (CI) were established. The Joanna Briggs Institute questionnaire for observational studies was applied to assess the risk of bias. The GRADE tool was used to assess the quality of evidence of the SR. RESULTS: A total of 251 potentially relevant studies were selected through the search strategy. After screening titles and abstracts, 11 full-text manuscripts were assessed for eligibility and nine observational studies were included in the meta-analysis. The present study showed an increase in micronuclei after the exposure (SMD = 0.21, 95% CI, 0.03 to 0.28, p = 0.02), with a Tau2index = 0.00, Chi2 = 2.35, and p-value = 0.97. Therefore, the articles selected were considered homogeneous and the I² of 0% indicated low heterogeneity. CONCLUSION: According to the studies analysed, although the quality of evidence was considered low, panoramic radiographs can cause genotoxic damage in the oral epithelium but with a small effect size.

Evaluation of the Genotoxicity of Endodontic Materials for Deciduous Teeth Using the Comet Assay

ABSTRACT Objective: To evaluate genotoxicity of zinc oxide, P. A. calcium hydroxide, mineral trioxide aggregate and an iodoform paste using comet assay on human lymphocytes. Material and Methods: Two positive controls were used: methyl-methanesulfonate for the P.A. calcium hydroxide and mineral trioxide aggregate; and doxorubicin for the iodoform paste and zinc oxide. There were also two negative controls: distilled water for the P.A. calcium hydroxide and mineral trioxide aggregate; and DMSO for the iodoform paste and zinc oxide. Comets were identified using fluorescence microscopy and 100 of them were counted on each of the three slides analyzed per drug test. A damage index was established, taking into consideration the score pattern that had previously been determined from the size and intensity of the comet tail. Analysis of variance, followed by Tukey's test, was used to compare the means of the DNA damage indices. Results: The DNA damage index observed for mineral trioxide aggregate (7.08 to 8.58) and P.A. calcium hydroxide (6.50 to 8.33), which were similar to negative control index. On the other hand, damage index for zinc oxide (104.7 to 218.50) and iodoform paste (115.7 to 210.7) were similar to positive control index. Conclusion: Iodoform paste and zinc oxide showed genotoxicity at all concentrations used.

Evaluation of genotoxicity after acute and chronic exposure to 2,4-dichlorophenoxyacetic acid herbicide (2,4-D) in rodents using machine learning algorithms.

2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most widely used herbicides in the world, but its mutagenic and carcinogenic potential is still controversial. We simulated environmental exposure to 2,4-D, with the objective of evaluating the genotoxic effect of acute and chronic exposure to 2,4-D in rodents. We also evaluated the performance of machine learning algorithms in detecting differences in exposure groups through recognition performed from genotoxic characteristics. In the acute phase, 88 Swiss mice were used, distributed in five groups and exposed to nebulizations at different time intervals (24, 48, 72 and 192 hr). In the chronic phase, 88 Wistar rats were used, distributed in two groups (inhaled and oral) and exposed for six months. Femoral bone marrow cells were collected for a micronucleus test and comet assay. Data were evaluated by pattern recognition algorithms. In acute exposure, medium and high concentrations induced DNA damage in the comet assay, but these concentrations did not increase micronucleated cells. In the chronic exposure, there was an increase in micronuclei and DNA damage in the comet assay in all exposed groups regardless of the exposure route. The data showed a robust pattern of distinction between exposed and nonexposed groups to 2,4-D. Our data showed that both acute inhalation exposure and chronic oral and inhalation exposure to 2,4-D can cause genotoxic effects regardless of concentration. Machine learning showed a clear distinction between the control groups and those exposed to 2,4-D, and the effects of exposure are not concentration-dependent.

Formaldehyde in occupational environments: literature review and an occupational health surveillance proposal / Formaldehído en ambientes laborales: revisión de la literatura y propuesta de vigilancia ocupacional

Abstract Introduction: Formaldehyde is a substance widely used in the industry; however, it is classified as mutagenic and carcinogenic to humans. In order to determine the risk of workers who are occupationally exposed to formaldehyde, it is necessary to monitor its environmental concentration levels and the biomarkers that allow identifying its potential health effects. Unfortunately, in Colombia there are not guidelines on occupational exposure to this substance. Objective: To review recent studies on occupational exposure to formaldehyde to design a monitoring and surveillance strategy for Colombian workers exposed to this substance. Materials and methods: A literature review was conducted in PubMed, MedLine, Science-Direct and Embase using the following search strategy: articles on occupational exposure to formaldehyde published in English or Spanish between 2013 and 2017. The following search terms were used: "occupational exposure", "formaldehyde" "mutagenicity test" y "DNA adducts" and their Spanish equivalents. Results: The initial search yielded 103 articles, of which only 36 met the inclusion criteria. Conclusions: Proper management of the risk derived from occupational exposure to formaldehyde, as well as the appropriate medical follow-up of these workers, requires the implementation of a series of interdisciplinary actions that allow the creation of a comprehensive occupational health surveillance system for workers exposed to this substance.

Resumen Introducción. El formaldehido es una sustancia ampliamente usada a nivel industrial; sin embargo, es considerada un agente mutagénico y carcinógeno para los humanos. Para determinar el grado de riesgo de los trabajadores ocupacionalmente expuestos (TOE) al formaldehido, debe hacerse un seguimiento de sus niveles de concentración ambiental y de los biomarcadores que permiten identificar su daño potencial para la salud. En Colombia, lamentablemente, no existen lineamientos respecto a la exposición ocupacional a esta sustancia. Objetivo. Revisar estudios recientes sobre exposición ocupacional a formaldehido para diseñar una estrategia de seguimiento y vigilancia de los TOE a esta sustancia en Colombia. Materiales y métodos. Se realizó una revisión de la literatura en PubMed, MedLine, ScienceDirect y Embase mediante la siguiente estrategia de búsqueda: artículos sobre exposición ocupacional a formaldehido publicados en inglés o español entre 2013 y 2017. Los términos de búsqueda fueron "occupational exposure", "formaldehyde" "mutagenicity test" y "DNA adducts" y sus equivalentes en español. Resultados. La búsqueda inicial arrojó 103 registros, sin embargo solo 36 artículos cumplieron los criterios de inclusión establecidos. Conclusiones. La gestión adecuada del riesgo derivado de la exposición ocupacional a formaldehido, asi como el seguimiento médico apropiado de estos trabajadores, requiere la implementación de una serie de acciones interdisciplinarias que permitan la creación de un sistema de vigilancia ocupacional integral de los TOE a esta sustancia.

Carcinogenicidade e mutagenicidade do malathion e seus dois análogos: uma revisão sistemática / Carcinogenicity and mutagenicity of malathion and its two analogues: a systematic review

Resumo O agrotóxico malathion vem sendo amplamente utilizado no mundo em programas de controle de arboviroses e em 2015 foi classificado pela Agência Internacional para Pesquisas em Câncer (IARC) como provável agente carcinogênico para seres humanos. Este trabalho objetivou a sistematização das evidências dos efeitos carcinogênicos e mutagênicos associados à exposição do malathion e seus análogos, malaoxon e isomalathion. A busca foi realizada nas bases de dados TOXLINE, PUBMED e SCOPUS por artigos originais publicados de 1983 a 2015. Do total de 273 artigos elegíveis, foram selecionados 73. Os resultados dos estudos in vitro e in vivo evidenciaram danos genéticos e cromossômicos provocados pelo malathion; os estudos epidemiológicos evidenciaram associações significativamente positivas para cânceres de tireóide, de mama, e ovariano em mulheres na menopausa. Estas evidências do efeito carcinogênico do malathion devem ser considerados diante de sua utilização em programas de controle de arboviroses.

Abstract Malathion has been widely used worldwide in arbovirus control programs. In 2015, it was classified by the International Agency for Research on Cancer (IARC) as a probable carcinogen to humans. This work aimed to systematize the evidence of the carcinogenic and mutagenic effects associated with the exposure of malathion and its analogs, malaoxon and isomalathion. The search was carried out in Toxline, PubMed and Scopus databases for original papers published from 1983 to 2015. In all, 73 papers were selected from a total of 273 eligible papers. The results of in vitro and in vivo studies showed mainly genetic and chromosomal damages caused by malathion. The epidemiological studies evidenced significant positive associations for thyroid, breast, and ovarian cancers in menopausal women. This evidence of the carcinogenic effect of malathion should be considered before its use in arbovirus control programs.

Modified comet assay with Giemsa staining: a suitable method for assessing genotoxicity in rats / Ensaio cometa modificado com coloração de Giemsa: um método adequado para avaliar a genotoxicidade em ratos

The present study tested a comet assay that was modified for compatibility with Giemsa staining to assess the drug genotoxicity in the peripheral blood of rats. We analysed the peripheral blood of 16 female Wistar rats (N=8 rats/group) from a control group and from a group that was treated with an intraperitoneal injection of 50mg cyclophosphamide/kg. The comet assay was carried out with modifications of the blood volume and immersion time in the lysing solution and different combinations of electrophoresis conditions (running time, voltage and current), to Giemsa staining. The lysing time and electrophoresis conditions allowed for the expression of all classes of DNA damage during the electrophoresis run, and the comets were efficiently stained with Giemsa. The technique showed high reproducibility for the DNA classes. The results demonstrate that the modified comet assay with Giemsa staining can be standardized for routine laboratory procedures using a 20µL blood sample, 3h and 30min immersions in the lysing solution and electrophoresis runs with 23 to 25 V and 310 and 360mA of electrical current. The modified comet assay with Giemsa staining that was described in the present study was standardized to be applied in the laboratory routine.(AU)

O presente estudo testou um ensaio cometa modificado para a coloração de Giemsa para avaliar a genotoxicidade de fármacos no sangue periférico de ratos. Analisou-se o sangue periférico de 16 ratas Wistar (n=8 ratas/grupo) de um grupo controle e de um grupo que foi tratado com uma injeção intraperitoneal de 50mg/kg pv. de ciclofosfamida. O ensaio cometa foi realizado com modificações do volume sanguíneo e do tempo de imersão na solução de lise, bem como com diferentes combinações de condições de eletroforese (tempo de corrida, tensão e corrente), para coloração de Giemsa. O tempo de lise e as condições de eletroforese permitiram a expressão de todas as classes de danos no DNA durante a corrida de eletroforese, e os cometas foram eficientemente corados com Giemsa. A técnica mostrou alta reprodutibilidade para as classes de DNA. Os resultados demonstram que o ensaio cometa modificado com coloração de Giemsa foi padronizado para procedimentos laboratoriais de rotina usando-se uma amostra de sangue de 20µL, 3h30min de imersão na solução de lise e eletroforese com 23 a 25 V e 310 e 360mA. O ensaio cometa modificado com coloração de Giemsa descrito foi padronizado para ser aplicado na rotina laboratorial.(AU)

Modified comet assay with Giemsa staining: a suitable method for assessing genotoxicity in rats / Ensaio cometa modificado com coloração de Giemsa: um método adequado para avaliar a genotoxicidade em ratos

The present study tested a comet assay that was modified for compatibility with Giemsa staining to assess the drug genotoxicity in the peripheral blood of rats. We analysed the peripheral blood of 16 female Wistar rats (N=8 rats/group) from a control group and from a group that was treated with an intraperitoneal injection of 50mg cyclophosphamide/kg. The comet assay was carried out with modifications of the blood volume and immersion time in the lysing solution and different combinations of electrophoresis conditions (running time, voltage and current), to Giemsa staining. The lysing time and electrophoresis conditions allowed for the expression of all classes of DNA damage during the electrophoresis run, and the comets were efficiently stained with Giemsa. The technique showed high reproducibility for the DNA classes. The results demonstrate that the modified comet assay with Giemsa staining can be standardized for routine laboratory procedures using a 20µL blood sample, 3h and 30min immersions in the lysing solution and electrophoresis runs with 23 to 25 V and 310 and 360mA of electrical current. The modified comet assay with Giemsa staining that was described in the present study was standardized to be applied in the laboratory routine.(AU)

O presente estudo testou um ensaio cometa modificado para a coloração de Giemsa para avaliar a genotoxicidade de fármacos no sangue periférico de ratos. Analisou-se o sangue periférico de 16 ratas Wistar (n=8 ratas/grupo) de um grupo controle e de um grupo que foi tratado com uma injeção intraperitoneal de 50mg/kg pv. de ciclofosfamida. O ensaio cometa foi realizado com modificações do volume sanguíneo e do tempo de imersão na solução de lise, bem como com diferentes combinações de condições de eletroforese (tempo de corrida, tensão e corrente), para coloração de Giemsa. O tempo de lise e as condições de eletroforese permitiram a expressão de todas as classes de danos no DNA durante a corrida de eletroforese, e os cometas foram eficientemente corados com Giemsa. A técnica mostrou alta reprodutibilidade para as classes de DNA. Os resultados demonstram que o ensaio cometa modificado com coloração de Giemsa foi padronizado para procedimentos laboratoriais de rotina usando-se uma amostra de sangue de 20µL, 3h30min de imersão na solução de lise e eletroforese com 23 a 25 V e 310 e 360mA. O ensaio cometa modificado com coloração de Giemsa descrito foi padronizado para ser aplicado na rotina laboratorial.(AU)

Exposição ambiental/ocupacional aos agrotóxicos em gestantes residentes em um município rural / Environmental/occupational exposure to pesticides of pregnant women living in a countryside municipality / Exposición ambiental/ocupacional a los agrotóxicos en gestantes residentes en un municipio rural

Objective: The study's goal has been to analyze if environmental or occupational exposure to pesticides can produce changes in pregnant women living in a countryside municipality. Methods: The participants of this study were twenty-three pregnant women, who both answered a questionnaire and donated biological material in order to perform Micronucleus (MN) Tests in lymphocytes, oral epithelial cells, and also for measuring the enzyme activity of erythrocyte acetylcholinesterase. Results: Considering the total analyzed samples, the following was found: an average of 8 ± 2.92 MN/1000 oral epithelial cells from urban participants; an average of 6.82 ± 3.43 MN/1000 oral epithelial cells from rural participants; and 100% of the microscope slides contained cells with two MN, which shows high intensity lesions to the DNA. There was found a high frequency of spontaneous abortions (34.8%), greater than in Brazil. Conclusion: The exposure of pregnant women living in a countryside municipality to pesticides may increase the rate of spontaneous abortions, as well as the chances of mutagenic effects

Objetivo: Analisar se a exposição ambiental ou ocupacional aos agrotóxicos causa alterações em gestantes residentes em um município rural. Métodos: Compuseram a amostra 23 gestantes, que responderam a um questionário e doaram amostras biológicas para a realização dos testes de micronúcleos (MN) em linfócitos, em células do epitélio oral, e para a dosagem da atividade da enzima acetilcolinesterase eritrocitária. Resultados: Obteve-se uma média de 8 ± 2,92 MN/1000 células do epitélio oral analisadas em amostras de participantes da zona urbana, 6,82 ± 3,43 MN/1000 de participantes da zona rural, e 100% das lâminas continham células com dois MN, o que demonstra lesões ao DNA de maior intensidade. Encontrou-se uma frequência elevada de casos de abortos espontâneos (34,8%), superior à encontrada no Brasil. Conclusão: A exposição de gestantes residentes em um município rural aos agrotóxicos eleva a taxa de abortos espontâneos, bem como as chances de ocorrência de efeitos mutagênicos

Objetivo: Analizar si la exposición ambiental o ocupacional a los agrotóxicos causa cambios en gestantes residentes en un municipio rural. Métodos: Compusieron la muestra 23 gestantes, que respondieron a un cuestionario y donaron muestras biológicas para la realización de las pruebas de micronúcleos (MN) en linfocitos, en células del epitelio oral, y para la dosificación de la actividad de la enzima acetilcolinesterasa eritrocitaria. Resultados: Se obtuvieron una media de 8 ± 2,92 MN / 1000 células del epitelio oral analizadas en muestras de participantes de la zona urbana, 6,82 ± 3,43 MN / 1000 de participantes de la zona rural, y el 100% de las láminas contenían células con dos MN, lo que demuestra lesiones al ADN de mayor intensidad. Se encontró una frecuencia elevada de casos de abortos espontáneos (34,8%), superior a la encontrada en Brasil. Conclusión: La exposición de gestantes residentes en un municipio rural a los agrotóxicos eleva la tasa de abortos espontáneos, así como las posibilidades de ocurrencia de efectos mutagênicos

Efeitos citotóxicos do aripiprazol nas linhagens celulares MKN45 e NIH3T3 e efeitos genotóxicos nos linfócitos sanguíneos periféricos humanos / Cytotoxic effects of aripiprazole on mkn45 and nih3t3 cell lines and genotoxic effects on human peripheral blood lymphocytes

ABSTRACT BACKGROUND: Gastric cancer is known as the fourth most common cancer. Current treatments for cancer have damaged the sensitive tissues of the healthy body, and in many cases, cancer will be recurrent. Therefore, need for treatments that are more effective is well felt. Researchers have recently shifted their attention towards antipsychotic dopamine antagonists to treat cancer. The anticancer activities of aripiprazole remain unknown. OBJECTIVE: This study aimed to evaluate the efficacy and safety of aripiprazole on gastric cancer and normal cell lines. METHODS: In this regard, the cytotoxicity and genotoxicity of aripiprazole were investigated in MKN45 and NIH3T3 cell lines by methyl tetrazolium assay and on peripheral blood lymphocytes by micronucleus assay. For this purpose, cells were cultured in 96 wells plate. Stock solutions of aripiprazole and cisplatin were prepared. After cell incubation with different concentrations of aripiprazole (1, 10, 25, 50, 100 and 200 μL), methyl tetrazolium solution was added. For micronucleus assay fresh blood was added to RPMI culture medium 1640 supplemented, and different concentrations of aripiprazole (50, 100 and 200 μL) were added. RESULTS: The finding of present study showed that the IC50 of aripiprazole in the cancer cell line (21.36 μg/mL) was lower than that in the normal cell line (54.17 μg/mL). Moreover, the micronucleus assay showed that the frequency of micronuclei of aripiprazole at concentrations below 200 μM was much less than cisplatin. CONCLUSION: Aripiprazole can be a good cytotoxic compound and good candidate for further studies of cancer therapy.

RESUMO CONTEXTO: O câncer gástrico é conhecido como o quarto câncer mais comum. Os tratamentos atuais para o câncer danificaram os tecidos sensíveis do corpo saudável e, em muitos casos, o cancro será recorrente. Portanto, a necessidade de tratamentos que são mais eficazes é desejada. Recentemente, os pesquisadores mudaram sua atenção para os antagonistas antipsicóticos da dopamina para tratar o câncer. As atividades anticâncer de aripiprazol permanecem desconhecidas. OBJETIVO: Este estudo objetivou avaliar a eficácia e a segurança do aripiprazol no câncer gástrico e nas linhagens celulares normais. MÉTODOS: A este respeito, a citotoxicidade e a genotoxicidade do aripiprazol foram investigadas em linhas celulares MKN45 e NIH3T3 por ensaio de metil tetrazólio e em linfócitos periféricos de sangue por ensaio de micronúcleos. Para este efeito, as células foram cultivadas em 96 placas. As soluções de estoque de aripiprazol e cisplatina foram preparadas. Após incubação celular com diferentes concentrações de aripiprazol (1, 10, 25, 50, 100 e 200 μL), a solução de metil tetrazólio foi adicionada. Para o ensaio do micronúcleo o sangue fresco foi adicionado ao meio de cultura RPMI 1640 suplementado, e as concentrações diferentes de aripiprazole (50, 100 e 200 μL) foram adicionadas. RESULTADOS: O presente estudo mostrou que o IC50 de aripiprazol na linhagem celular cancerosa (21,36 μg/mL) foi menor do que na linha celular normal (54,17 μg/ mL). Além disso, o ensaio de micronúcleos demonstrou que a frequência de micronúcleos de aripiprazol em concentrações inferiores a 200 μM foi muito inferior à cisplatina. CONCLUSÃO: O aripiprazol pode ser um bom composto citotóxico e bom candidato para estudos adicionais da terapia do câncer.

Evaluation of hydroxyurea genotoxicity in patients with sickle cell disease / Avaliação da indução de genotoxicidade pela hidroxiureia em pacientes com doença falciforme

ABSTRACT Objective To evaluate the induction of DNA damage in peripheral blood mononuclear cells of patients with sickle cell disease, SS and SC genotypes, treated with hydroxyurea. Methods The study subjects were divided into two groups: one group of 22 patients with sickle cell disease, SS and SC genotypes, treated with hydroxyurea, and a Control Group composed of 24 patients with sickle cell disease who were not treated with hydroxyurea. Peripheral blood samples were submitted to peripheral blood mononuclear cell isolation to assess genotoxicity by the cytokinesis-block micronucleus cytome assay, in which DNA damage biomarkers - micronuclei, nucleoplasmic bridges and nuclear buds - were counted. Results Patients with sickle cell disease treated with hydroxyurea had a mean age of 25.4 years, whereas patients with sickle cell disease not treated with hydroxyurea had a mean age of 17.6 years. The mean dose of hydroxyurea used by the patients was 12.8mg/kg/day, for a mean period of 44 months. The mean micronucleus frequency per 1,000 cells of 8.591±1.568 was observed in the Hydroxyurea Group and 10.040±1.003 in the Control Group. The mean frequency of nucleoplasmic bridges per 1,000 cells and nuclear buds per 1,000 cells for the hydroxyurea and Control Groups were 0.4545±0.1707 versus 0.5833±0.2078, and 0.8182±0.2430 versus 0.9583±0.1853, respectively. There was no statistically significant difference between groups. Conclusion In the study population, patients with sickle cell disease treated with the standard dose of hydroxyurea treatment did not show evidence of DNA damage induction.

RESUMO Objetivo Avaliar o efeito da indução de danos ao DNA em células monocelulares do sangue periférico de pacientes com doença falciforme, genótipos SS e SC, tratados com hidroxiureia. Métodos Os sujeitos da pesquisa foram divididos em dois grupos: um de 22 pacientes com doença falciforme genótipos SS e SC tratados com hidroxiureia, e o outro controle, composto por 24 pacientes com doença falciforme que não eram tratados com o fármaco. As amostras de sangue periférico foram submetidas ao isolamento de células mononucleares do sangue periférico para avaliação da genotoxicidade pelo ensaio de micronúcleo citoma com bloqueio da citocinese, tendo sido quantificados os biomarcadores de danos ao DNA - micronúcleos, pontes nucleoplasmáticas e brotamento nuclear. Resultados Os pacientes com doença falciforme tratados com hidroxiureia apresentaram média de idade de 25,4 anos, enquanto aqueles com doença falciforme não tratados com hidroxiureia tiveram média de idade de 17,6 anos. A dose média de hidroxiureia utilizada pelos pacientes foi de 12,8mg/kg/dia, por período médio de 44 meses. A frequência média de micronúcleos por 1.000 células de 8,591±1,568 foi observada no Grupo Hidroxiureia e de 10,040±1,003 no Grupo Controle. Adicionalmente, a frequência média de pontes nucleoplasmáticas por 1.000 células e brotamento nuclear por 1.000 células para o Grupo Hidroxiureia e Controle foi de 0,4545±0,1707 versus 0,5833±0,2078, e de 0,8182±0,2430 versus 0,9583±0,1853, respectivamente. Não houve diferença estatisticamente significativa entre os grupos. Conclusão Na população estudada de pacientes com doença falciforme com tratamento em dose padrão de hidroxiureia, não houve evidência de indução de danos ao DNA.

Cytotoxicity and genotoxicity of calcium silicate-based cements on an osteoblast lineage

Abstract Several calcium silicate-based biomaterials have been developed in recent years, in addition to Mineral Trioxide Aggregate (MTA). The aim of this study was to evaluate the cytotoxicity, genotoxicity and apoptosis/necrosis in human osteoblast cells (SAOS-2) of pure calcium silicate-based cements (CSC) and modified formulations: modified calcium silicate-based cements (CSCM) and three resin-based calcium silicate cements (CSCR1) (CSCR 2) (CSCR3). The following tests were performed after 24 hours of cement extract exposure: methyl-thiazolyl tetrazolium (MTT), apoptosis/necrosis assay and comet assay. The negative control (CT-) was performed with untreated cells, and the positive control (CT+) used hydrogen peroxide. The data for MTT and apoptosis were submitted to analysis of variance and Bonferroni's posttest (p < 0.05), and the data for the comet assay analysis, to the Kruskal-Wallis and Dunn tests (p < 0.05). The MTT test showed no significant difference among the materials in 2 mg/mL and 10 mg/mL concentrations. CSCR3 showed lower cell viability at 10 mg/mL. Only CSC showed lower cell viability at 50 mg/mL. CSCR1, CSCR2 and CSCR3 showed a higher percentage of initial apoptosis than the control in the apoptosis test, after 24 hours exposure. The same cements showed no genotoxicity in the concentration of 2 mg/mL, with the comet assay. CSC and CSCR2 were also not genotoxic at 10 mg/mL. All experimental materials showed viability with MTT. CSC and CSCR2 presented a better response to apoptosis and genotoxicity evaluation in the 10 mg/mL concentration, and demonstrated a considerable potential for use as reparative materials.

Micronucleus test in peripheral blood of rats treated with hyperbaric oxygen after subtotal splenectomy preserving the lower pole

PURPOSE: To assess the mutagenic potential of the oxygen inhalation therapy (HBO), by means of the micronucleus test, performed in peripheral blood of rats that underwent subtotal splenectomy with lower pole preservation (ESTPI), after HBO sessions or simulations. METHODS: Eighteen male Wistar rats, were distributed into three groups of six animals: group 1 - submitted to ESTPI and HBO sessions; group 2 - submitted to ESTPI and HBO simulations; group 3 - underwent cyclophosphamide administration. In groups 1 and 2, blood samples from the animals' tails were collected before surgery (T0) and immediately after the 13th HBO session or simulation (T1). In group 3, tail blood samples were collected from animals before (T0) and 24 hours after (T1) cyclophosphamide (CP) delivery. The number of micronucleated normochromatic erythrocytes (MNNCE) was determined by blind counting 2000 normochromatic erythrocytes (NCE) per animal. RESULTS: Micronuclei average after CP delivery in group 3 was higher than before its use, thus confirming the mutagenic activity of this drug (p=0.01). In groups 1 and 2, no significant difference in the average of Micronuclei was observed when comparing it to blood samples before and after the 13th HBO session or simulation. CONCLUSION: The treatment protocol used in this study did not induce Micronucleus formation in animals submitted to ESTPI and HBO treatment or simulation. .

Micronucleus test in peripheral blood of rats treated with hyperbaric oxygen after subtotal splenectomy preserving the lower pole

PURPOSE: To assess the mutagenic potential of the oxygen inhalation therapy (HBO), by means of the micronucleus test, performed in peripheral blood of rats that underwent subtotal splenectomy with lower pole preservation (ESTPI), after HBO sessions or simulations.METHODS: Eighteen male Wistar rats, were distributed into three groups of six animals: group 1 - submitted to ESTPI and HBO sessions; group 2 - submitted to ESTPI and HBO simulations; group 3 - underwent cyclophosphamide administration. In groups 1 and 2, blood samples from the animals' tails were collected before surgery (T0) and immediately after the 13th HBO session or simulation (T1). In group 3, tail blood samples were collected from animals before (T0) and 24 hours after (T1) cyclophosphamide (CP) delivery. The number of micronucleated normochromatic erythrocytes (MNNCE) was determined by blind counting 2000 normochromatic erythrocytes (NCE) per animal.RESULTS:Micronuclei average after CP delivery in group 3 was higher than before its use, thus confirming the mutagenic activity of this drug (p=0.01). In groups 1 and 2, no significant difference in the average of Micronuclei was observed when comparing it to blood samples before and after the 13th HBO session or simulation.CONCLUSION: The treatment protocol used in this study did not induce Micronucleus formation in animals submitted to ESTPI and HBO treatment or simulation.(AU)

Evaluation of genotoxicity induced by repetitive administration of local anaesthetics: an experimental study in rats / Avaliação da genotoxicidade induzida pela administração repetida de anestésicos locais: um estudo experimental em ratos / Evaluación de la genotoxicidad inducida por la administración repetida de anestésicos locales: un estudio experimental en ratones

BACKGROUND AND OBJECTIVE: Previous studies regarding the effects of some local anaesthetics have suggested that these agents can cause genetic damage. However, they have not been tested for genotoxicity related to repetitive administration. The aim of this study was to evaluate the genotoxic potential of local anaesthetics upon repetitive administration. METHODS: 80 male Wistar rats were divided into: group A - 16 rats intraperitoneally injected with lidocaine hydrochloride 2%; group B - 16 rats IP injected with mepivacaine 2%; group C - 16 rats intraperitoneally injected with articaine 4%; group D - 16 rats IP injected with prilocaine 3% (6.0 mg/kg); group E - 8 rats subcutaneously injected with a single dose of cyclophosphamide; and group F - 8 rats intraperitoneally injected with saline. Eight rats from groups A to D received a single dose of anaesthetic on Day 1 of the experiment; the remaining rats were dosed once a day for 5 days. RESULTS: The median number of micronuclei in the local anaesthetics groups exposed for 1 or 5 days ranged from 0.00 to 1.00, in the cyclophosphamide-exposed group was 10.00, and the negative control group for 1 and 5 days was 1.00 and 0.00, respectively (p < 0.0001). A significant difference in the number of micronuclei was observed between the cyclophosphamide group and all local anaesthetic groups (p = 0.0001), but not between the negative control group and the local anaesthetic groups (p > 0.05). CONCLUSION: No genotoxicity effect was observed upon repetitive exposure to any of the local anaesthetics evaluated. .

JUSTIFICATIVA E OBJETIVOS: Estudos anteriores sobre os efeitos de alguns anestésicos locais sugeriram que esses agentes podem causar alterações genéticas. No entanto, esses agentes não são testados para genotoxicidade relacionada à administração repetida. O objetivo deste estudo foi avaliar o potencial genotóxico de anestésicos locais após repetidas administrações. MÉTODOS: 80 ratos Wistar machos foram alocados em: grupo A - 16 ratos receberam injeção por via intraperitoneal (IP) de cloridrato de lidocaína a 2%; grupo B - 16 ratos receberam injeção IP com mepivacaína a 2%; grupo C - 16 ratos receberam injeção IP de articaína a 4%; grupo D - 16 ratos receberam injeção IP de prilocaína a 3% (6 mg kg-1); grupo E - oito ratos receberam injeção subcutânea em dose única de ciclofosfamida; grupo F - oito ratos receberam injeção IP com solução salina. Oito ratos dos grupos de A a D receberam uma dose única de anestésico no Dia 1 da experiência; os ratos restantes foram dosados uma vez por dia durante cinco dias. RESULTADOS: A mediana do número de micronúcleos nos grupos com anestésicos locais expostos por um ou cinco dias variou de 0 a 1; no grupo exposto à ciclofosfamida foi de 10 e no grupo controle negativo no primeiro e quinto dias foi de 1 e 0, respectivamente (p < 0,0001). Uma diferença significativa foi observada no número de micronúcleos entre o grupo ciclofosfamida e todos os grupos com anestésicos locais (p = 0,0001), mas não entre o grupo controle negativo e os grupos com anestésicos locais (p > 0,05). CONCLUSÃO: Nenhum efeito de genotoxicidade foi observado após a exposição repetida a qualquer um dos anestésicos locais avaliados. .

JUSTIFICACIÓN Y OBJETIVOS: Estudios previos sobre los efectos de algunos anestésicos locales han mostrado que esos agentes pueden causar alteraciones genéticas. Sin embargo, esos agentes no son testados para la genotoxicidad relacionada con la administración repetida. El objetivo de este estudio fue evaluar el potencial genotóxico de anestésicos locales después de repetidas administraciones. MÉTODOS: 80 ratones Wistar machos se dividieron en: grupo A: 16 ratones que recibieron inyección por vía intraperitoneal (IP) de clorhidrato de lidocaína al 2%; grupo B: 16 ratones a los que se les administró inyección IP con mepivacaína al 2%; grupo C: 16 ratones que recibieron inyección IP de articaína al 4%; grupo D: 16 ratones a los que se les administró inyección IP de prilocaína al 3% (6 mg/kg); grupo E: 8 ratones que recibieron inyección subcutánea en dosis única de ciclofosfamida; grupo F: 8 ratones que recibieron inyección IP con solución salina. Ocho ratones de los grupos A a D recibieron una dosis única de anestésico el primer día de la experiencia; los ratones restantes se dosificaron una vez por día durante 5 días. RESULTADOS: La mediana del número de micronúcleos en los grupos con anestésicos locales expuestos durante uno o 5 días varió de 0 a 1; en el grupo expuesto a la ciclofosfamida fue de 10 y en el grupo control negativo en el primero y quinto día fue de 1 y 0 respectivamente (p < 0,0001). Se observó una diferencia significativa en el número de micronúcleos entre el grupo ciclofosfamida y todos los grupos con anestésicos locales (p = 0,0001), pero no entre el grupo control negativo y los grupos con anestésicos locales (p > 0,05). CONCLUSIÓN: Ningún efecto de genotoxicidad fue observado después de la exposición repetida a cualquiera de los anestésicos locales evaluados. .

[Evaluation of genotoxicity induced by repetitive administration of local anaesthetics: an experimental study in rats]. / Avaliação da genotoxicidade induzida pela administração repetida de anestésicos locais: um estudo experimental em ratos.

BACKGROUND AND OBJECTIVE: Previous studies regarding the effects of some local anaesthetics have suggested that these agents can cause genetic damage. However, they have not been tested for genotoxicity related to repetitive administration. The aim of this study was to evaluate the genotoxic potential of local anaesthetics upon repetitive administration. METHODS: 80 male Wistar rats were divided into: group A - 16 rats intraperitoneally injected with lidocaine hydrochloride 2%; group B - 16 rats IP injected with mepivacaine 2%; group C - 16 rats intraperitoneally injected with articaine 4%; group D - 16 rats IP injected with prilocaine 3% (6.0mg/kg); group E - 8 rats subcutaneously injected with a single dose of cyclophosphamide; and group F - 8 rats intraperitoneally injected with saline. Eight rats from groups A to D received a single dose of anaesthetic on Day 1 of the experiment; the remaining rats were dosed once a day for 5 days. RESULTS: The median number of micronuclei in the local anaesthetics groups exposed for 1 or 5 days ranged from 0.00 to 1.00, in the cyclophosphamide-exposed group was 10.00, and the negative control group for 1 and 5 days was 1.00 and 0.00, respectively (p<0.0001). A significant difference in the number of micronuclei was observed between the cyclophosphamide group and all local anaesthetic groups (p=0.0001), but not between the negative control group and the local anaesthetic groups (p>0.05). CONCLUSION: No genotoxicity effect was observed upon repetitive exposure to any of the local anaesthetics evaluated.

Assessment of methyl methacrylate genotoxicity by the micronucleus test

The aim of this study was to evaluate the genotoxic potential of methyl methacrylate (MMA) vapor by simulating standard occupational exposure of 8 hours per day and using the micronucleus test. We used 32 adult male Wistar rats divided into three groups: A - 16 rats exposed to MMA for 8 hours a day, B - Eight rats receiving single subcutaneous doses of cyclophosphamide on the first day of the experiment (positive control), C - Eight rats receiving only water and food ad libitum (negative control). Eight rats from group A and all of the rats from groups B and C were sacrificed 24 hours after beginning the experiment (acute exposure in group A). The remaining animals in group A were sacrificed 5 days after the experiment began (repeated exposure assessment in group A, simulating occupational exposure 40 hours/week). Femoral bone marrow was collected from each rat at the time of sacrifice for use in the micronucleus test. Two slides were completed per animal and were stained with Giemsa staining. Two thousand polychromatic erythrocytes were counted per animal. The Kruskal-Wallis test followed by a multiple comparisons test (Dunn test) was used for statistical analysis. The median number of micronuclei was 7.00 in the group exposed to MMA for 1 day, 2.00 in the group exposed to MMA for 5 days, 9.00 in the group exposed to cyclophosphamide (positive control) and 0.756 in the negative control group (p < 0.0001). MMA was genotoxic when measured after 1 day of exposure but was not evidently genotoxic after 5 days.