Cytotoxicity and genotoxicity of endodontic irrigants on human cells / Citotoxicidade e genotoxicidade de irrigantes endodônticos em células humanas

OBJECTIVE: Endodontic irrigants solutions with antibacterial activity have been used in treatment of teeth with infected root canals; however, these solutions can irritate periapical tissues. The aim of this study was to evaluate the cytotoxity and genotoxicity of different endodontic irrigants solutions – sodium hypochlorite (1% and 2%), calcium hydroxide (0.2%), and HCT20 in human KB cells. MATERIAL AND METHOD: Cells were incubated with solutions for 2 and 24 hours. The cell viability was assessed after the trypan blue exclusion and the frequency of cell death mechanism (apoptotic or necrotic) was determined by acridine orange/ethidium bromide fluorescent dyeing test. The genotoxicity effects were assessed by the micronucleus assays. RESULTS AND DISCUSSION: The results showed that Ca(OH)2 alone or in combination with tergentol (HCT20), and NaOCl induced cytotoxicity in KB causing death cells by apoptosis. The micronuclei test showed that KB treated with NaOCl (1%) present an increase in the frequency of micronucleus compared to the control group.

OBJETIVO: Soluções irrigadoras com atividade antibacteriana têm sido usadas no tratamento de dentes com canais radiculares infectados; entretanto, essas soluções podem irritar os tecidos periapicais. O objetivo deste estudo foi avaliar a citotoxicidade e genotoxicidade de diferentes soluções irrigadoras – hipoclorito de sódio (1% e 2%), hidróxidode cálcio (0,2 %) e HCT em células humanas KB. MATERIAL E MÉTODO: As células foram incubadas em soluções por 2 e 24 horas. A viabilidade celular foi determinada após exclusão do tripan blue e a frequência de mecanismo de morte celular (apoptótica ou necrótica) foi determinada pelo teste acridine Orange/ethidium bromide fluorescen dyeing. Os efeitos de genotoxicidade foram determinados pelo ensaio de micronúcleos. RESULTADOS E DISCUSSÃO: Os resultados demonstraram que o Ca(OH2), isoladamente ou em combinação com Tergentol™ (HCT20) e NaOCl, induziram citotoxicidade em KB, causando morte celular por apoptose. O teste de micronúcleos demonstrou que KB tratado codm NaOCl (1%) apresentou aumento na frequência de microdnúcleos quando comparadocom o grupo controle.

[Cytotoxic effects of cyclooxygenase enzyme inhibitor drugs [COX1, COX2] on KB cell line: an in-vitro study]

Cyclooxygenase enzyme inhibitors have been recently investigated regarding their inhibitory effect on cancer. The aim of the present study was to investigate the cytotoxic effects of cyclooxygenase enzyme inhibitor drugs on KB cell line [squamous cell carcinoma] in vitro. This experimental study used the powder of Ibuprophen, Indomethacin, Acetaminophen, Naproxen, Celecoxib, Mefenamic acid, Diclofenac Na, Aspirin and Piroxicam. These drugs were dissolved in proper solvents according to specified company instructions [SIGMA Company]. The KB cell lines were proliferated through MTT Assay method. The concentration of drugs that causes 50% decrease in cell growth was computed [IC50]. Post-hoc test was used to compare the effect of various concentrations of drugs on vitality of cells and variance test was applied to compare the mean of IC50 between various drugs by using SPSS version 13.5 statistical software. This study showed that Celecoxibt, Mefenamic Acid and Diclofenac Na drugs have cytotoxicity effects on KB cell line with the IC50 values of 1.5, 4.5 and 15.4 micro g/ml, respectively. Also, it was found that the Naproxen, Indomethacin and Aspirin drugs with the IC50 mean of 50 micro g/ml can inhibit cell growth. Celecoxib and Diclofenac Na drugs have cytotoxicity effects. Therefore, at the experimental stage, these medicines have the potential to be used as oral anticancer drugs

Preparación y toxicidad in vitro de un conjugado entre el factor de crecimiento epidérmico y la adriamicina / Preparation and in vitro toxicity between a conjugate of Epidermal Growth Factor and adriamycine

La principal dificultad de la terapia del cáncer en la actualidad es la utilización de agentes tóxicos cuya actividad antitumoral no es específica. Por tal razón se ha pensado en la unión de agentes tóxicos como toxinas o drogas a factores de crecimiento, hormonas y anticuerpos monoclonales para lograr toxicidad específica sobre las células cancerosas. En este trabajo se presenta la construcción de un conjugado mediante una unión covalente entre el factor de crecimiento epidérmico (EGF) y la adriamicina (ADM). El conjugado retiene la habilidad del EGF de reconocer sus receptores en células de carcinoma mamario, sin perder afinidad y la ADM retiene su toxicidad. La toxicidad del conjugado fue revertida por adición de un exceso de EGF libre y fue dependiente de la cantidad de receptores de EGF presentes en la superficie celular

Estudio farmacológico preclínico de un carbamato con interés oncológico / Preclinical pharmacologic trial of a carbamate of oncologoc interest

El 43GV040 es un producto sintético análogo al dietildetiocarbamato de sodio con perspectiva de uso en la clínica oncológica. Es por ello que se estudiaron sus efectos sobre la línea celular KB así como en algunos modelos in vivo e in vitro en 2 especies de animales (ratas y curiel), sobre el aparato cardiovascular, respiratorio y tracto gastrointestinal. No se observaron efectos directos en ileon y tráquea. A altas concentraciones se encontró un ligero aumento del inotropismo. En el animal intacto, la dosis mayor ensayada produce una ligera disminución de la frecuencia cardíaca y la presión arterial que se recupera. Estos estudios nos señalan la posibilidad de su introducción en el arsenal terapéutico