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Introducción. Los tumores neoplásicos se caracterizan por su invasividad y metástasis. Las células neoplásicas tienen heterogeneidad genética, por lo cual pueden desarrollar resistencia a los quimioterápicos. Por esta razón, las plantas continúan siendo una fuente importante de nuevos productos anticancerígenos. Objetivo. Evaluar la actividad citotóxica y antiproliferativa de un extracto rico en fucoidan de Lessonia trabeculata nativa (EFLt) sobre la línea celular de adenocarcinoma mamario murino, triple negativo 4T1. Métodos. La citotoxicidad y la IC50 se determinaron en monocapas de 4T1 empleando el reactivo MTT. Para demostrar la actividad antiproliferativa se aplicaron los métodos de cierre de herida y anticlonogénico utilizando las IC50 del EFLt y Dox (doxorubicina). El cierre de herida fue evaluado mediante barrido de tiempos discretos; el efecto anticlonogénico fue evaluado 7 días postratamiento mediante el conteo de colonias y se determinó la fracción de sobrevivencia. Adicionalmente, se evaluaron la citotoxicidad y actividad antiproliferativa combinando las IC50 de EFLt y Dox. El porcentaje de migración y conteo de colonias se realizó con el programa ImageJ. Resultados. La IC50 del EFLt (950 μg/mL) produjo 56% de citotoxicidad, 80,3% de inhibición de la migración celular, 68% de inhibición en la formación de colonias. La IC50 de Dox fue 0,5 μg/mL. Conclusiones. El EFLt ejerce citotoxicidad dependiente de la concentración y tiene efecto antiproliferativo sobre 4T1. Se requiere continuar los ensayos en modelos de mayor complejidad que permitan esclarecer el potencial antitumoral del EFLt.

Introduction. Neoplastic tumors are characterized by invasiveness and metastasis. Neoplastic cells are genetically heterogeneous and can develop resistance to chemotherapeutic agents. For this reason, plants continue to be an important source of new anticancer products. Objective. To determine the cytotoxic and antiproliferative activity of a fucoidan-rich extract of native Lessonia trabeculata (EFLt) on the tripe negative murine mammary adenocarcinoma cell line 4T1. Methods. Cytotoxicity and IC50 were determined in 4T1 monolayers using the MTT reagent. To demonstrate antiproliferative activity, "wound" closure and anticlonogenic methods were applied using the IC50 of EFLt and Doc (doxorubicin). "Wound" closure was evaluated by discrete times sweep to determine percentage inhibition of cell migration; the anticlonogenic effect was evaluated by colony counting 7 days after treatment and the survival fraction was determined. In addition, cytotoxicity and antiproliferative activity were evaluated by combining the IC50 of EFLt and Dox. Percent migration and colony counts were performed using ImageJ software. Results. The IC50 (950 μg/mL) of EFLt was 56% cytotoxicity, 80,3% inhibition of cell migration, 68% inhibition of colony formation.The ICof Dox was 0,5 μg/mL. Conclusions. EFLt exerts concentration-dependent cytotoxicity and antiproliferative effect on 4T1. Further studies in more complex models are needed to elucidate the anti-tumor potential of EFLt.

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Enteroaggregative Escherichia coli (EAEC) and enterohemorrhagic E. coli (EHEC) are E. coli pathotypes associated with unmanageable diarrhea in children and adults. An alternative to the treatment of infections caused by these microorganisms is the use of the bacteria of the Lactobacillus genus; however, the beneficial effects on the intestinal mucosa are specific to the strain and species. The interest of this study consisted of analyzing the coaggregation properties of Lactobacillus casei IMAU60214, as well as the effect of cell-free supernatant (CSF) on growth and anti-cytotoxic activity in a cell model of the human intestinal epithelium for an agar diffusion assay (HT-29) and the inhibition of biofilm formation on plates of DEC strains of the EAEC and EHEC pathotypes. The results showed that L. casei IMAU60214 exhibits time-dependent coaggregation (35-40%) against EAEC and EHEC that is similar to the control E. coli ATCC 25922. The CSF showed antimicrobial activity (20-80%) against EAEC and EHEC depending on the concentration. In addition, the formation and dispersion of biofilms of the same strains decrease, and the proteolytic pre-treatment with catalase and/or proteinase K (1 mg/mL) of CSF reduces the antimicrobial effect. When evaluating the effect in HT-29 cells pre-treated with CFS on the toxic activity induced by the EAEC and EHEC strains, a reduction of between 30 and 40% was observed. The results show that L. casei IMAU60214 and its CSF have properties that interfere with some properties associated with the virulence of the EAEC and EHEC strains that cause intestinal infection, which supports their use for the control and prevention of infections caused by these bacteria.

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Abstract Introduction: Halting ventilation during cardiopulmonary bypass (CPB) is implemented to operate in a less bleeding setting. It sustains a better visualization of the operation area and helps to perform the operation much more comfortably. On the other hand, it may lead to a series of postoperative lung complications such as atelectasis and pleural effusion. In this study, we investigated the effects of low tidal volume ventilation on inflammatory cytokines during CPB. Methods: Twenty-eight patients undergoing cardiovascular surgery were included in the study. Operation standards and ventilation protocols were determined and patients were divided into two groups: patients ventilated with low tidal volume and non-ventilated patients. Plasma samples were taken from patients preoperatively, perioperatively from the coronary sinus and postoperatively after CPB. IL-6, IL-8, TNF-α and C5a levels in serum samples were studied with enzyme-linked immunosorbent assay (ELISA) kits. Results: C5a, IL-6, IL-8 and TNF-α were similar when compared to the low tidal volume ventilated and non-ventilated groups (P>0.05) Comparing the groups by variables, IL-6 levels were increased during CPB in both groups (P=0.021 and P=0.001), and IL-8 levels decreased in the ventilation group during CPB (P=0.018). Conclusion: Our findings suggest that low tidal volume ventilation may reduce the inflammatory response during CPB. Although the benefit of low tidal volume ventilation in CPB has been shown to decrease postoperative lung complications such as pleural effusion, atelectasis and pneumonia, we still lack more definitive and clear proofs of inflammatory cytokines encountered during CPB.

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Resumo Fundamento O tecido adiposo epicárdico (TAE) é aumentado em comorbidades comuns na insuficiência cardíaca (IC). Dessa forma, o TAE teria o potencial de mediar efeitos que levam à deterioração da função cardíaca. Objetivos Esta metanálise tem o objetivo de investigar se a quantidade de TAE em todos os tipos de IC e cada tipo de IC são significativamente diferentes dos pacientes de controle. Métodos Esta metanálise seguiu as diretrizes da Meta-analysis of Observational Studies in Epidemiology (Metanálise de estudos observacionais em epidemiologia). A pesquisa foi realizada nos bancos de dados MEDLINE, Embase e Lilacs até novembro de 2020. Dois autores realizaram a triagem, a extração de dados e a avaliação de qualidade. Um p-valor <0,05 foi definido como estatisticamente significativo. Resultados Foram incluídos oito estudos observacionais, compreendendo 1248 pacientes no total, dos quais 574 eram de controle, 415 tinham IC com fração de ejeção reduzida (ICFER) e 259 tinham IC com fração de ejeção de faixa média ou preservada (ICFEfm ou ICFEP). A quantidade de TAE não era diferente entre todos os tipos de IC e o grupo de controle (DMP = -0,66, IC 95%: -1,54 a 0,23, p =0,14) . Analisando cada fenótipo de IC separadamente, pacientes com ICFER tinham TAE reduzido em comparação aos pacientes de controle (DMP = 1,27, IC 95%: - 1,87 a -0,67, p <0,0001), enquanto os pacientes com ICFEfm ou ICFEP tiveram TAE aumentado em comparação aos pacientes de controle (DMP = 1,24, IC 95%: 0,99 a 1,50, p <0,0001). Conclusão A quantidade de TAE não era significativamente diferente entre todos os tipos de IC e o grupo de controle. Em pacientes com ICFER o volume de TAE era reduzido, enquanto em pacientes com ICFEP e ICFEfm, a quantidade de TAE era significativamente aumentada. Número de registro PROSPERO: CRD42019134441.

Abstract Background Epicardial adipose tissue (EAT) is increased in comorbidities common in heart failure (HF). In this sense, EAT could potentially mediate effects that lead to an impaired cardiac function. Objectives This meta-analysis aims to investigate if the amount of EAT in all-types of HF and each HF phenotype is significantly different from control patients. Methods This meta-analysis followed the Meta-analysis Of Observational Studies in Epidemiology guidelines. The search was performed in the MEDLINE, Embase, and Lilacs databases until November 2020. Two authors performed screening, data extraction, and quality assessment. A p-value <0.05 was defined as statistically significant. Results Eight observational studies were included, comprehending 1,248 patients in total, from which 574 were controls, 415 had HF with reduced ejection fraction (HFrEF) and 259 had HF with mid-range or preserved ejection fraction (HFmrEF or HFpEF). The amount of EAT was not different between all types of HF and the control group (SMD = -0.66, 95% CI: -1.54 to 0.23, p =0.14). Analyzing each HF phenotype separately, patients with HFrEF had a reduced EAT when compared to the controls (SMD= -1.27, 95% CI: - 1.87 to -0.67, p <0.0001), while patients with HFmrEF or HFpEF showed an increased EAT when compared to controls (SMD= 1.24, 95% CI: 0.99 to 1.50, p <0.0001). Conclusion The amount of EAT was not significantly different between all types of HF and the control group. In patients with HFrEF, the EAT volume was reduced, whereas in HFpEF and HFmrEF, the amount of EAT was significantly increased. PROSPERO registration number: CRD42019134441.

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INTRODUCTION: Halting ventilation during cardiopulmonary bypass (CPB) is implemented to operate in a less bleeding setting. It sustains a better visualization of the operation area and helps to perform the operation much more comfortably. On the other hand, it may lead to a series of postoperative lung complications such as atelectasis and pleural effusion. In this study, we investigated the effects of low tidal volume ventilation on inflammatory cytokines during CPB. METHODS: Twenty-eight patients undergoing cardiovascular surgery were included in the study. Operation standards and ventilation protocols were determined and patients were divided into two groups: patients ventilated with low tidal volume and non-ventilated patients. Plasma samples were taken from patients preoperatively, perioperatively from the coronary sinus and postoperatively after CPB. IL-6, IL-8, TNF-α and C5a levels in serum samples were studied with enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: C5a, IL-6, IL-8 and TNF-α levels were similar when compared to the low tidal in volume ventilated and non-ventilated groups (P>0.05). Comparing the groups by variables, IL-6 levels were increased during CPB in both groups (P=0.021 and P=0.001), and IL-8 levels decreased in the ventilation group during CPB (P=0.018). CONCLUSION: Our findings suggest that low tidal volume ventilation may reduce the inflammatory response during CPB. Although the benefit of low tidal volume ventilation in CPB has been shown to decrease postoperative lung complications such as pleural effusion, atelectasis and pneumonia, we still lack more definitive and clear proofs of inflammatory cytokines encountered during CPB.

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Abstract: This paper evaluates the physicochemical and biological properties of experimental resin-based dual-cured calcium aluminate (CA) and calcium titanate (CTi) materials for vital pulp therapy (VPT). The experimental dual-cured materials were obtained as two pastes: a) Bis-EMA 10, PEG 400, DHEPT, EDAB, camphorquinone, and butylated hydroxytoluene; and b) fluoride ytterbium, Bis-EMA 10, Bis-EMA 30, benzoyl peroxide, and butylated hydroxytoluene. The materials were divided into six groups based on the added calcium component: MTA (MTA®, Angelus); CLQ (Clinker-Fillapex®, Angelus); CA (calcined at ,1200°C in pastes a and b); CA800 (calcined at 800°C in paste a); CA1200 (calcined at 1,200°C in paste a); and CTi (paste a). The real-time degree of conversion and rate of polymerization (n = 3), diametral tensile strength (n = 10), hydrogen potential (n = 15), calcium ion release (n = 10), water sorption and solubility (n = 10), and cell viability (n = 6) were evaluated. One- and two-way ANOVA and Tukey's post hoc test were used in the analysis of the parametric data, and Kruskal-Wallis and Dunn's multiple tests were used to analyze the nonparametric data (α = 0.05). CLQ, CA800 and CA1200 had the highest diametral tensile strength. The water solubility of MTA was similar to that of CA800, CA1200 and CTi. CA800 and CA1200 resulted in cell viabilities similar to those of MTA and CLQ. The experimental dual-cured CA-based material that calcined at 800°C showed physicochemical and biological properties suitable for VPT, and similar to those of MTA.

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This study aims to evaluate changes in quality of life of cancer patients at the beginning of the first and the second cycle of chemotherapy (CT) in hospitals in Belo Horizonte, Minas Gerais State, Brazil. Longitudinal, prospective, descriptive study with a quantitative approach. We enrolled 230 patients, from a broader cohort, diagnosed with the five most frequent types of cancer (breast, colorectal, cervical, lung, and head and neck), aged 18 years or older, who were initiating CT for the first time. quality of life was assessed with the EORTC QLQ-C30 version 3, applied at the beginning of the first and second chemotherapy cycle. The paired Wilcoxon test was used to identify differences in quality of life between the two time points. A multivariate linear regression analysis was performed using the bootstrap method to investigate potential predictors of global health Status/quality of life. There was a significant increase in patients' emotional function scores (p < 0.001) as well as symptom scores for pain (p = 0.026), diarrhea (p = 0.018), and nausea/vomiting (p < 0.001) after initiation of CT. Widowhood was associated with improvements in the global health Status/quality of life (p = 0.028), whereas the presence of cervical cancer (p = 0.034) and being underweight (p = 0.033) were related to poorer global health status/quality of life scores. CT has detrimental effects on patients' physical health but, on the other hand, it leads to improvements in the emotional domain. Patients' individual characteristics at the beginning of CT are associated with changes in their quality of life. Our study could help identify these characteristics.

O estudo teve como objetivo avaliar as mudanças na qualidade de vida de pacientes oncológicos no início do primeiro e segundo ciclos de quimioterapia (QT) em hospitais em Belo Horizonte, Minas Gerais, Brasil. Foi realizado um estudo descritivo, prospectivo e longitudinal com uma abordagem quantitativa. Arrolamos 230 pacientes de uma coorte maior, diagnosticados com os cinco tipos de câncer mais frequentes (mama, colorretal, colo uterino, pulmão e cabeça e pescoço), com idade 18 anos ou mais e que estavam no início da QT. A qualidade de vida foi avaliada com o EORTC QLQ-C30, versão 3, aplicado no início do primeiro e segundo ciclos de QT. O teste pareado de Wilcoxon foi utilizado para identificar diferenças na qualidade de vida entre os dois momentos. Para investigar potenciais preditores de estado de saúde global/qualidade de vida, foi realizada uma análise de regressão linear multivariada com o método bootstrap. Houve um aumento significativo na pontuação da função emocional dos pacientes (p < 0,001) e de dor (p = 0,026), diarreia (p = 0,018) e náusea/vômito (p < 0,001) após o início da quimioterapia. Estado civil "viúvo/a" esteve associado a melhoras no estado de saúde global/qualidade de vida (p = 0,028), enquanto presença de câncer do colo uterino (p = 0,034) e baixo peso (p = 0,033) estiveram relacionados a piores resultados no estado de saúde global/qualidade de vida. A QT tem efeitos deletérios na saúde física dos pacientes, mas leva a melhorias no domínio emocional. As características individuais dos pacientes no início da QT estão associadas a mudanças na qualidade vida. Nosso estudo pode ajudar a identificar essas características.

El objetivo del presente estudio fue evaluar cambios en la calidad de vida de pacientes con cáncer, entre el principio del primero y segundo ciclo de quimioterapia (CT), en hospitales en Belo Horizonte, Brasil. Se llevó a cabo un estudio longitudinal, prospectivo, descriptivo con un enfoque cuantitativo. Participaron 230 pacientes, de una cohorte más amplia, diagnosticados con los cinco tipos de cáncer más frecuentes (pecho, colorrectal, cervical, pulmón, cabeza y cuello), con 18 años y más, que estaban comenzando CT por primera vez. La calidad de vida fue evaluada mediante EORTC QLQ-C30 versión 3, aplicada al comienzo del primer y segundo ciclo de quimioterapia. Se usó el test pareado de Wilcoxon para identificar las diferencias en calidad de vida entre dos puntos en el tiempo. Para investigar los predictores potenciales del estatus de salud global/calidad de vida, se realizó un análisis lineal multivariado, usando el método de Bootstrap. Hubo un aumento significativo en las puntuaciones de las funciones emocionales de los pacientes (p < 0,001), así como las puntuaciones para dolor (p = 0,026), diarrea (p = 0,018) y náusea/vómitos (p < 0,001) tras el comienzo de la quimioterapia. Ser viudo/a estuvo asociado con mejoras en el estatus de salud global/calidad de vida (p = 0,028), mientras que la presencia de cáncer cervical (p = 0,034) y estar por debajo del peso (p = 0,033) estuvieron relacionados con puntuaciones más bajas estatus de salud global/calidad de vida. La CT tiene efectos perjudiciales en la salud física de los pacientes, sin embargo, por otro lado, conduce a mejoras en el ámbito emocional. Las características individuales de pacientes al comienzo de la CT están asociadas con cambios en su calidad de vida. Nuestro estudio podría ayudar a identificar estas características.

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RESUMEN Objetivos: Determinar el efecto citotóxico y genotóxico in vitro del extracto crudo y etanólico del rizoma de Curcuma longa L. Materiales y métodos: El efecto citotóxico fue evaluado utilizando líneas celulares DU-145, HT-29, 3T3 BALB/c. Se hallaron los porcentajes de crecimiento en 48 horas y se determinó la concentración inhibitoria 50 (CI50). El efecto genotóxico en el ADN genómico humano se determinó mediante el método Tomasevich. Resultados: El extracto crudo produjo una CI50 de 12,98 ± 0,21 μg/mL para la línea celular tumoral HT-29, que es inferior a DU-145 con una CI50 de 36,77 ± 9,12 μg/mL; el extracto etanólico presentó una CI50 de 13,24 ± 0,77 y 20,54 ± 2,58 µg/mL para ambas líneas celulares, respectivamente; el compuesto estándar curcumina presentó una CI50 de 3,96 ± 0,60 y 13,94 ± 2,79 μg/mL, respectivamente. El extracto crudo a concentraciones de 50 y 100 mg/mL fragmentó entre el 40% a 95% de ADN genómico humano; mientras que, a 200 mg/mL, la fragmentación fue mayor al 95%. El extracto etanólico a todas las concentraciones no fragmentó el ADN. La curcumina a 200 mg/mL fragmentó menos del 5% de ADN genómico humano. Conclusiones: Los extractos crudo y etanólico de Curcuma longa L. demuestran efecto citotóxico in vitro diferencial para la línea celular tumoral humana DU-145 y HT29 semejante al compuesto estándar curcumina. El extracto crudo de Curcuma longa L. presenta una potente actividad genotóxica in vitro frente al ADN genómico humano, esta actividad está ausente en el extracto etanólico.

ABSTRACT Objectives: To determine the in vitro cytotoxic and genotoxic effect of the crude and ethanolic extract from the Curcuma longa L. rhizome. Materials and methods: The cytotoxic effect was evaluated using DU-145, HT-29, 3T3 BALB/c cell lines. The growth percentages in 48 hours; and the half maximal inhibitory concentration (IC50) were determined. The genotoxic effect on human genomic DNA was determined using the Tomasevich method. Results: Crude extract produced an IC50 of 12.98 ± 0.21 μg/mL for the HT-29 tumor cell line, which is lower than the value obtained for DU-145, with an IC50 of 36.77 ± 9.12 μg/mL. The ethanolic extract presented an IC50 of 13.24 ± 0.77 and 20.54 ± 2.58 μg/mL for both cell lines, respectively; the curcumin standard compound presented an IC50 of 3.96 ± 0.60 and 13.94 ± 2.79 μg/mL, respectively. Crude extract concentrations of 50 and 100 mg/mL fragmented between 40% to 95% of human genomic DNA; while at 200 mg/mL, fragmentation was greater than 95%. The ethanolic extract at all concentrations did not fragment the DNA. Curcumin at 200 mg/mL fragmented less than 5% of human genomic DNA. Conclusions: The crude and ethanolic extracts of Curcuma longa L. demonstrate different in vitro cytotoxic effects for the human tumor cell lines DU-145 and HT-29; similar to the standard curcumin compound. The crude extract of Curcuma longa L. shows a potent genotoxic in vitro activity against human genomic DNA; this type of effect is not produced by the ethanolic extract.

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Toxin synergism is a complex biochemical phenomenon, where different animal venom proteins interact either directly or indirectly to potentiate toxicity to a level that is above the sum of the toxicities of the individual toxins. This provides the animals possessing venoms with synergistically enhanced toxicity with a metabolic advantage, since less venom is needed to inflict potent toxic effects in prey and predators. Among the toxins that are known for interacting synergistically are cytotoxins from snake venoms, phospholipases A2 from snake and bee venoms, and melittin from bee venom. These toxins may derive a synergistically enhanced toxicity via formation of toxin complexes by hetero-oligomerization. Using a human keratinocyte assay mimicking human epidermis in vitro, we demonstrate and quantify the level of synergistically enhanced toxicity for 12 cytotoxin/melittin-PLA2 combinations using toxins from elapids, vipers, and bees. Moreover, by utilizing an interaction-based assay and by including a wealth of information obtained via a thorough literature review, we speculate and propose a mechanistic model for how toxin synergism in relation to cytotoxicity may be mediated by cytotoxin/melittin and PLA2 complex formation.

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Composites have been proven to have a cytotoxic effect on a variety of tissues and cells. Aim: The aim of this study was to analyse the degree of conversion of resins and its correlation with the cell viability in primary gingival fibroblasts. Methods: Resin-based silorane (Filtek P90) and conventional methacrylate resins (Filtek Z100, Filtek Z250 and Filtek Z350XT) were used to evaluate cell viability and the degree of conversion. The resins were light-cured by a LED for 20 and 40 seconds. The degree of conversion was analysed by Fourier transform infrared spectroscopy. Cellular metabolism was evaluated after 24 hours by the MTT assay (n = 6) using the storage solution of composite resin for either 24 hours or 12 days. Variance analysis (ANOVA) with a Bonferroni correction (p < 0.05) was performed to compare the groups. Results: The composite Filtek P90 showed a higher degree of conversion when polymerised for 40 or 20 seconds, while the composites Filtek Z100, Filtek Z250 and Filtek Z350XT showed similar degree of conversion. Only the Filtek Z100 resin was cytotoxic. Conclusion: We found no statistically significant correlation between cell viability and the degree of conversion

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Abstract Background: The diterpene Sclareol has antimicrobial action, cytotoxic and cytostatic effects and anti-tumor activities. However, researches on the cardiovascular system are scarce. Objective: This study was designed to investigate the mechanisms involved in the Sclareol cardiovascular effect in normotensive and hypertensive rats. Methods: The arterial hypertension was promoted using 2-kidneys 1-clip model in rats. The effect of sclareol on blood pressure was performed by using three dose (10, 20 and 40 mg/kg). Cumulative dose-response curves for Sclareol were determined for endothelium-intact and endothelium-denuded aortic rings in presence or absence of L-NAME and ODQ. The NOx levels were measure in the plasma sample. Results: The Sclareol administration in vivo caused a significant reduction in blood pressure in both groups. In vitro the sclareol promoted relaxation in aorta, with endothelium, pre-contracted to Phe. The inhibitors of the nitric oxide synthase and soluble guanylate cyclase were as efficient as the removal of endothelium, in inhibiting the Sclareol-induced relaxation. Otherwise, it was no change of NOx. Also, for unknown reasons, the Sclareol is not selective for hypertensive animals. Conclusion: The diterpene Sclareol showed in vivo hypotensive and in-vitro vasodilator effects; The chemiluminescence plasmatic NO analysis showed no significant difference between groups and The Sclareol exhibit better effect on normotensive than hypertensive animals to reduce blood pressure. It is concluded that the diterpenes metabolites would be a promising source prototype for the development of new agents in the cardiovascular therapy.

Resumo Fundamento: O diterpeno Esclareol tem ação antimicrobiana, efeitos citotóxicos e citostáticos e atividades antitumorais. No entanto, pesquisas sobre o sistema cardiovascular são escassas. Objetivo: Este estudo foi desenvolvido para investigar os mecanismos envolvidos no efeito cardiovascular de Esclareol em ratos normotensos e hipertensos. Métodos: A hipertensão arterial foi promovida utilizando modelo de 2 clones de 1-clipe em ratos. O efeito do esclareol sobre a pressão arterial foi realizado utilizando três doses (10, 20 e 40 mg/kg). As curvas dose-resposta cumulativas para Esclareol foram determinadas para anéis aórticos endotélio-intactos e desprovidos de endotélio na presença ou ausência de L-NAME e ODQ. Os níveis de NOx foram medidos na amostra de plasma. Resultados: A administração de Esclareol in vivo causou uma redução significativa na pressão sanguínea em ambos os grupos. In vitro o esclareol promoveu relaxamento na aorta, com endotélio, pré-contraído a Phe. Os inibidores da óxido nítrico sintase e da guanilato ciclase solúvel foram tão eficientes quanto a remoção do endotélio, na inibição do relaxamento induzido por Esclareol. Por outra parte, não houve mudança de NOx. Além disso, por razões desconhecidas, o Sclareol não é seletivo para animais hipertensos. Conclusão: O diterpeno Esclareol apresentou efeitos hipotensores in vivo e vasodilatadores in vitro; A análise de NO plasmático por quimioluminescência não mostrou diferença significativa entre os grupos e O Esclareol exibe melhor efeito sobre os animais normotensos do que hipertensos para reduzir a pressão arterial. Conclui-se que os metabólitos de diterpenos seriam um protótipo de fonte promissora para o desenvolvimento de novos agentes na terapia cardiovascular.

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La mordedura de araña es un accidente muy común e importante problema de salud pública en lugares con clima tropical y se presenta como un problema muy frecuente en algunas regiones de Latinoamérica. En Perú las especies de araña que presentan más casos de esta problemática son Loxosceles laeta, Latrodectus mactans and Phoneutria spp. El presente trabajo pretende explicar, clarificar y categorizar estas mordeduras de arañas, con el fin de dar a conocerlas para ayudar a que los profesionales de la salud tengan un mayor conocimiento sobre las mismas para un mejor manejo de los casos que se les presenten. (AU)

Spider bites are a common and important public health issue in tropical climates, and become a frequent problem in certain Latin American regions. In Peru, the main species of spiders that represent this problematic are Loxosceles laeta, Latrodectus mactans and Phoneutria spp. The present article intends to explain, clarify and categorize these spider bites, in order to make them known by every health professional to its better management. (AU)

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The pathogenesis of dermonecrosis induced by the venom of the African spitting cobra Naja nigricollis was investigated in a mouse model. Intradermal injection of venom induced a macroscopic necrotic lesion. Histological examination revealed early edema of the dermis, followed by blistering, loss of skin appendages and reduction in cellularity. By 24 h, necrosis of the dermis was evident, sections of epidermis were lost, and a fibrinoid hyaline material filled the damaged areas. Abundant inflammatory infiltrate was present in the hypodermis and basal dermis, and there was an increment in the expression of matrix metalloproteinases (MMPs). Thrombi were observed in blood vessels. Abundant cells were present in the dermis by 7 days. By 14 and 28 days, re-epithelization had occurred, collagen was widespread in the dermis, and few skin appendages were present. The RP-HPLC fractions that reproduced the necrotic activity were composed of low molecular mass cytotoxins of the three-finger toxin family and, to a lesser extent, of phospholipases A2 (PLA2). Inhibition of PLA2 of venom by p-bromophenacyl bromide did not reduce the area of necrosis, but modified the appearance of necrotic regions. Depletion of neutrophils and inhibition of venom metalloproteinases and tissue MMPs did not affect dermonecrosis. IgG and F(ab')2 antivenoms were effective in the neutralization of dermonecrosis when incubated with venom prior to injection. However, when antivenoms were administered immediately after venom injection, dermonecrosis was reduced only to a partial extent, underscoring the difficulties in neutralizing this effect with antivenoms.

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Although opportunistic pathogens, coagulase-negative staphylococci (CoNS), including Staphylococcus epidermidis and Staphylococcus haemolyticus, have long been regarded as avirulent organisms. The role of toxins in the development of infections caused by CoNS is still controversial. The objective of this study was to characterize the presence of enterotoxin and cytotoxin genes in S. epidermidis and S. haemolyticus isolates obtained from blood cultures. Cytotoxin genes were detected by PCR using novel species-specific primers. Among the 85 S. epidermidis and 84 S. haemolyticus isolates, 95.3% and 79.8%, respectively, carried at least one enterotoxin gene. The most frequent enterotoxin genes were sea (53.3%), seg (64.5%) and sei (67.5%). The seg gene was positively associated with S. epidermidis (p = 0.02), and this species was more toxigenic than S. haemolyticus. The hla/yidD gene was detected in 92.9% of S. epidermidis and the hla gene in 91.7% of S. haemolyticus isolates; hlb was detected in 92.9% of the S. epidermidis isolates and hld in 95.3%. Nosocomial Staphylococcus epidermidis and S. haemolyticus isolates exhibited a high toxigenic potential, mainly producing the non-classical enterotoxins seg and sei. The previously unreported detection of hla/yidD and hlb in S. epidermidis and S. haemolyticus using species-specific primers showed that these hemolysin genes differ between CoNS species and that they are highly frequent in blood culture isolates.

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OBJECTIVE: The aim of this study was to assess the in vitro cytotoxicity of acrylic resins of different colors over time. METHODS: Specimens were divided into 4 groups (n = 6) according to the color of the acrylic resin (Orto Class, Clássico, Campinas, São Paulo, Brazil): Group 1, clear acrylic resin; Group 2, pink acrylic resin; Group 3, blue acrylic resin; and Group 4, green acrylic resin. All specimens were fabricated according to the mass manipulation technique and submitted to mechanical polishing protocol. The control was performed with an amalgam specimen (C+), a glass specimen (C-) and cell control (CC). Specimens were immersed in Minimum Eagle's Medium (MEM) and incubated for 24 h at 37ºC. The extracts from the experimental material were filtered and mixed with L929 fibroblast. Cytotoxicity was evaluated at four different times, 24, 48, 72 and 168 h. After contact, cells were incubated for 24 h and added to 100 µ of 0.01% neutral red dye. The cells were incubated for 3 h for pigment incorporation and fixed. Cells viability was determined by a spectroscopic (BioTek, Winooski, Vermont, USA) with a 492-nm wavelength λ=492 nm). RESULTS: There were no statistical differences between the experimental groups and the CC and C- groups. CONCLUSION: Clear, pink, blue and green self-curing acrylic resins fabricated by means of the mass manipulation technique and mechanically polished are not cytotoxic. Neither the pigment added to the self-curing acrylic resin nor the factor of time influenced the cytotoxicity of the material.

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RESUMO

OBJECTIVE: The aim of this study was to assess the in vitro cytotoxicity of acrylic resins of different colors over time. METHODS: Specimens were divided into 4 groups (n = 6) according to the color of the acrylic resin (Orto Class, Clássico, Campinas, São Paulo, Brazil): Group 1: clear acrylic resin; group 2: pink acrylic resin; group 3: blue acrylic resin and group 4: green acrylic resin. All specimens were fabricated according to the mass manipulation technique and submitted to mechanical polishing protocol. The control was performed with an amalgam specimen (C+), a glass specimen (C-) and cell control (CC). Specimens were immersed in Minimum Eagle's Medium (MEM) and incubated for 24 h at 37o C. The extracts from the experimental material were filtered and mixed with L929 fibroblast. Cytotoxicity was evaluated at 4 different times, 24, 48, 72 and 168 h. After contact, cells were incubated for 24 h and added to 100 µ of 0.01% neutral red dye. The cells were incubated for 3 h for pigment incorporation and fixed. Cells viability was determined by a spectroscopic (BioTek, Winooski, Vermont, USA) with a 492-nm wavelength λ=492 nm). RESULTS: There were no statistical differences between the experimental groups and the CC and C- groups. CONCLUSION: Clear, pink, blue and green self-curing acrylic resins fabricated by means of the mass manipulation technique and mechanically polished are not cytotoxic. Neither the pigment added to the self-curing acrylic resin nor the factor of time influenced the cytotoxicity of the material. .

OBJETIVO: avaliar, in vitro, a citotoxicidade de resinas acrílicas autopolimerizáveis, de diferentes cores, ao longo do tempo. MÉTODOS: os corpos de prova foram divididos em quatro grupos (n = 3), de acordo com a cor da resina acrílica utilizada (Orto Class, Clássico, São Paulo/SP), sendo: grupo 1, acrílica incolor; grupo 2, acrílica rosa; grupo 3, acrílica azul; e, grupo 4, acrílico verde. Todos os corpos de prova foram confeccionados pela técnica de massa e polidos mecanicamente. Um corpo de prova de amálgama, um de vidro e célula constituíram o controle positivo (C+), controle negativo (C-), e controle de célula (CC), respectivamente. Em seguida, esses foram imersos em meio mínimo essencial de Eagle (MEM) por 24h, quando se removeu o sobrenadante e colocou-os em contato com fibroblastos L929. Avaliou-se a citotoxicidade em quatro períodos: 24, 48, 72 e 168h. Após o contato com o meio, as células foram incubadas por 24h e adicionou-se 100µ do corante vermelho neutro a 0,01%. Posteriormente, as células foram incubadas por 3h, para incorporação do corante, e fixadas. A contagem das células viáveis foi realizada em espectrofotômetro (BioTek, Winooski, EUA), com um comprimento de onda de 492nm (λ = 492nm). RESULTADOS: não houve diferença estatística entre os grupos experimentais e os grupos CC e C-. CONCLUSÇÕES: as resinas acrílicas autopolimerizáveis incolor, rosa, azul e verde, manipuladas pela técnica de massa e polidas mecanicamente não são citotóxicas. O corante utilizado em resinas autopolimerizáveis e tempo não influenciam na citotoxocidade do material. .

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