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The emergence of resistant fungal species and the toxicity of currently available antifungal drugs are relevant issues that require special consideration. Cyclodextrins inclusion complexes could optimize the antimicrobial activity of such drugs and create a controlled release system with few side effects. This study aimed to assess the in vitro toxicity and antifungal effectiveness of nystatin (Nys) and chlorhexidine (Chx) complexed or not with ß-cyclodextrin (ßCD). First, a drug toxicity screening was performed through the Artemia salina bioassay. Then, the minimum inhibitory concentrations (MICs) against Candida albicans were determined with the broth microdilution test. After MICs determination, the cytotoxicity of the drugs was evaluated through the methyl-thiazolyl-tetrazolium (MTT) and neutral red (NR) assays and through cell morphology analysis. The PROBIT analysis was used to determine the median lethal concentration (LC50), and the cell viability values were submitted to one-way analysis of variance(ANOVA)/Tukey (α = 0.05). Overall, the ßCD-complexed antifungals were less toxic against A. salina than their raw forms, suggesting that inclusion complexes can reduce the toxicity of drugs. The MICs obtained were as follows: Nys 0.5 mg/L; Nys:ßCD 4 mg/L; Chx 4 mg/L; and Chx:ßCD 8 mg/L. Chx showed significant cytotoxicity (MTT: 12.9 ± 9.6%; NR: 10.6 ± 12.5%) and promoted important morphological changes. Cells exposed to the other drugs showed viability above 70% with no cellular damage. These results suggest that antifungals complexed with ßCD might be a biocompatible option for the treatment of Candida-related infections.

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This systematic review and meta-analysis aimed to assess the cytotoxic and genotoxic impacts of waterpipe smoking on oral health. The databases MEDLINE, Cochrane Library and Dimensions were searched to find studies evaluating whether waterpipe smokers exhibited any cytotoxic or genotoxic effects on their oral cells compared to non-smokers, with regard to mouth neoplasms. Particularly, changes in DNA methylation and p53 expression were assessed. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were adopted for the systematic review. Review Manager was utilised for statistical analysis with a significance level at P <0.05. To assess the grades of the included articles, a risk of bias analysis was summarised. A forest plot, including some of the included articles included, was created regarding the different grades. A total of 20 studies were included in this review. The results showed that waterpipe smoking has cytotoxic and genotoxic effects on oral cells, with a risk difference of 0.16. Although the published articles are few in number, all confirm the devastating effects of waterpipe smoking related to the carcinogenicity. Waterpipe smoking is harmful to oral health. It causes a series of detrimental cellular and genetic modifications such as acanthosis, epithelial dysplasia and hyperparakeratosis. In addition, waterpipe smoke contains several carcinogenic compounds. As it releases many harmful organic compounds, waterpipe smoking increases the incidence of oral cancer.

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Cyanobacterial blooms have been recognized as a problem in fresh water for about 150 years. Over the past 50 years, experimental studies on the subject have gained importance considering the increasing need to control toxic cyanobacterial blooms. This article presents information on the different lines of research that have been undertaken on zooplankton-cyanobacteria interactions over the past 50 years. These include information on filtering/ingestion rates and phytoplankton preferences of small and large rotifers, cladocerans, and copepods; growth rates of zooplankton on cyanobacterial diets; feeding rates of other freshwater invertebrates on cyanobacteria; role of zooplankton in top-down biomanipulation efforts; effect of cyanotoxins on zooplankton; bioaccumulation of cyanotoxins; and physical and chemical control of cyanobacterial blooms. We also highlight measures that have led to successful lake management and improvement of water quality in selected waterbodies.

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Aims: The present study assessed the toxicity of a novel calcium silicate-based root canal sealer (Bio-C Sealer) in comparison to Endosequence BC Sealer and AH Plus through a lethality assay involving brine shrimp (Artemia salina). Methods: Brine shrimp cysts were incubated for 24 h for the hatching of the larvae, which were then exposed to different concentrations (2.5, 5, 10, 20, 40, 80, and 100 µg/mL) of the test endodontic sealers for 24 h, followed by the determination of the survival rate. Statistical Analysis Used: One-way repeated-measures ANOVA and the Newman-Keuls post hoc test were used to compare the different materials as well as different concentrations of the same material. Dunnett's test was used to compare the different concentrations and different sealers to the control. The lethal concentration of each endodontic sealer necessary to kill 50% of the brine shrimp larvae (LC50) was also determined. Results: The toxicity of Bio-C (10, 20, 40, 80, and 100 µg/mL) and Endosequence BC Sealer (20, 80, and 100 µg/mL) was lower than that of AH Plus. No significant difference was found between Bio-C and Endosequence BC Sealer or among the different intragroup concentrations of these sealers. In the AH Plus group, concentrations ≥5.0 µg/mL exhibited greater toxicity compared to the concentration of 2.5 µg/mL and the control. AH Plus had the lowest LC50 (59.95 µg/mL), whereas Bio-C and Endosequence BC Sealer had LC50 values >200 µg/mL. Conclusions: Bio-C Sealer proved to be less toxic than AH Plus and exhibited similar toxicity to that of Endosequence BC Sealer.

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OBJECTIVES: The present study aimed to compare the in vitro cytocompatibility of two etch-and-rinse (Adper Scothbond, Optibond) and two self-etch (Clearfill SE Bond and Single Bond Universal) dental adhesives through a dentin-barrier model with human pulp fibroblasts. METHODS: Human fibroblasts were placed on a plastic device containing 500µm human dentin discs treated with each adhesive or without treatment (control). Other groups were directly exposed to media conditioned with adhesive samples according to ISO 10993-5:2009. After 24h exposure, cell viability was assessed by XTT, and released inflammatory mediators were detected with a multiparametric immunoassay. RESULTS: The standardized test without barrier indicated both etch-and-rinse adhesives and self-etch as cytotoxic, promoting viabilities under 70% of the control group (p<0.05). The dentin-barrier model identified increased cell viability for self-etch adhesives, with Clearfill SE Bond identified as non-cytotoxic. The immunoassay evidenced high rates of cytokines by cells exposed to the conditioned media of Adper Scotchbond, Optibond S, and Single Bond Universal. CONCLUSIONS: The use of a dentin-barrier in vitro model detected a better biocompatibility for self-etching adhesives and, in the case of Clearfill SE Bond, with a reversion from cytotoxic to biocompatible when compared to the indirect standardized test. CLINICAL SIGNIFICANCE: The use of a dentin-barrier in vitro model was able to detect a better biocompatibility for self-etching adhesives when compared to the indirect standardized test and presents itself as a predictive in vitro method for assessing the cytotoxicity of dental restorative materials that may simulate the clinical condition more accurately.

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RESUMEN Objetivos. Determinar el efecto genotóxico de la tartrazina en linfocitos de sangre periférica de Mus musculus BALB/c. Materiales y métodos. Se realizó un estudio experimental, a través de cinco grupos, con cinco ratones en cada uno. Se les registró el peso durante 17 semanas y, en la semana 15 se les administró suero fisiológico (control negativo), dicromato de potasio 25 mg/kg de peso corporal (pc) (control positivo) y tartrazina a dosis de 0,75 mg/kg pc, 7,5 mg/kg pc y 75 mg/kg pc, durante siete días, a excepción del control positivo que fue en dosis única. Luego, cada 24 h se obtuvo una muestra de sangre periférica de la cola y se realizó el frotis, secado y coloración. Posteriormente, se realizó el conteo de 1000 linfocitos por muestra de cada ratón, en todos los tratamientos. Resultados. Los tres tratamientos con tartrazina no causaron diferencias significativas en el peso de ratones a la semana 15, pero sí produjeron diferencias significativas en la frecuencia de linfocitos micronucleados, siendo el tratamiento con tartrazina de 75 mg/kg pc el de mayor efecto genotóxico, induciendo un promedio de 1,63 ± 0,08 linfocitos micronucleados, comparado con el control positivo que generó un promedio de 1,42 ± 0,08 linfocitos micronucleados. Conclusiones. La tartrazina produjo un efecto genotóxico, incrementando el número de linfocitos micronucleados, a dosis de 0,75; 7,5 y 75 mg/kg pc y no afecta el peso corporal durante siete días de administración en M. musculus BALB/c.

ABSTRACT Objectives. To determine the genotoxic effect of tartrazine on peripheral blood lymphocytes of BALB/c Mus musculus. Materials and methods. An experimental study was carried out using five groups, with five mice in each group. Their weight was registered for 17 weeks, and at week 15 they were administered physiological saline solution (negative control), potassium dichromate at 25 mg/kg body weight (bw) (positive control) and tartrazine at doses of 0.75 mg/kg bw, 7.5 mg/kg bw and 75 mg/kg bw, for seven days, with the exception of the positive control which was a single dose. Then, every 24 hours, a peripheral blood sample was obtained from the tail, which was then smeared, dried and stained. Subsequently, 1000 lymphocytes were counted for each sample from each mouse, for all treatment groups. Results. The three tartrazine treatments did not cause significant differences in the weight of mice at week 15, but did produce significant differences in the frequency of micronucleated lymphocytes, with the 75 mg/kg bw tartrazine treatment having the greatest genotoxic effect, inducing an average of 1.63 ± 0.08 micronucleated lymphocytes, compared to the positive control which obtained an average of 1.42 ± 0.08 micronucleated lymphocytes. Conclusions. Tartrazine produced a genotoxic effect, increasing the number of micronucleated lymphocytes, at doses of 0.75; 7.5 and 75 mg/kg bw and did not affect body weight during seven days of administration to BALB/c M. musculus.

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This study determined phytochemical composition, antifungal activity and toxicity in vitro and in vivo of Syzygium cumini leaves extract (Sc). Thus, was characterized by gas chromatography coupled to mass spectrometry and submitted to determination of Minimum Inhibitory (MIC) and Fungicidal concentrations (MFC) on reference and clinical strains of Candida spp. and by growth kinetics assays. Toxicity was verified using in vitro assays of hemolysis, osmotic fragility, oxidant and antioxidant activity in human erythrocytes and by in vivo acute systemic toxicity in Galleria mellonella larvae. Fourteen different compounds were identified in Sc, which showed antifungal activity (MIC between 31.25-125µg/mL) with fungistatic effect on Candida. At antifungal concentrations, it demonstrated low cytotoxicity, antioxidant activity and neglible in vivotoxicity. Thus, Sc demonstrated a promising antifungal potential, with low toxicity, indicating that this extract can be a safe and effective alternative antifungal agent.

Este estudio determinó la composición fitoquímica, la actividad antifúngica y la toxicidad in vitro e in vivo del extracto de hojas de Syzygium cumini (Sc). Así, se caracterizó mediante cromatografía de gases acoplada a espectrometría de masas y se sometió a determinación de Concentraciones Mínimas Inhibitorias (CMI) y Fungicidas (MFC) sobre cepas de referencia y clínicas de Candida spp. y mediante ensayos de cinética de crecimiento. La toxicidad se verificó mediante ensayos in vitro de hemólisis, fragilidad osmótica, actividad oxidante y antioxidante en eritrocitos humanos y por toxicidad sistémica aguda in vivo en larvas de Galleria mellonella. Se identificaron catorce compuestos diferentes en Sc, que mostraron actividad antifúngica (CMI entre 31.25-125 µg/mL) con efecto fungistático sobre Candida. En concentraciones antifúngicas, demostró baja citotoxicidad, actividad antioxidante y toxicidad in vivo insignificante. Por lo tanto, Sc demostró un potencial antifúngico prometedor, con baja toxicidad, lo que indica que este extracto puede ser un agente antifúngico alternativo seguro y eficaz.

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The fish embryo test (FET) is an alternative to the classic freshwater toxicity test used to assess environmental hazards and risks to fish. This test has been standardized and adopted by the Organization for Economic and Cooperation and Development (OECD). As salinity may affect the substances' toxicity, we describe the development of an alternative euryhaline test species for embryonic ecotoxicological tests: the Brazilian silverside Atherinella brasiliensis (Quoy & Gaimard, 1825). This species is broadly distributed along the coast of South America and is able to inhabit a broad range of environmental and saline conditions. Ours is the first study on the maintenance of a native South American species for natural reproduction and the generation of embryos for tests. The embryos used are transparent and possess fluorescent cells which have only been seen in a few species and which may be used as markers, making it an alternative assessment tool for the lethal and sublethal substances in marine and estuarine environments. We provide a detailed description and analysis of embryonic development under different salinities and temperatures. The embryos and larvae developed in similar ways at different salinities, however as temperatures increased, mortality also increased. We considered the effects of the reference toxicants Zn2+ and SDS using a protocol similar to the FET that was standardized for zebrafish. Brazilian silverside embryos are as sensitive as freshwater, or euryhaline fish, to the surfactant but are more resistant to metals prior to hatching. We were able to show the advantages of the Brazilian silverside as a model for a marine fish embryo test (FETm) with high levels of reproducibility and little contaminated waste.

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The objective of this study was to evaluate the effects of AgNPs on Artemia salina and Allium cepa, evaluating the influence of the dilution solutions on the particle behavior. The AgNPs were synthesized by chemical reduction of AgNO3 (3 and 5 mmol L-1) with sodium borohydride and stabilized with PVA (polyvinyl alcohol) and CMC (sodium carboxymethyl cellulose). The toxicity of AgNPs was evaluated in Artemia salina (mortality) using Meyer's solution as a diluent and in Allium cepa (chromosomal aberrations) using reconstituted hard water. AgNPs showed characteristic molecular absorption bands. Particles with CMC presented hydrodynamic radius between 4 and 102 nm and with PVA between 7 and 46 nm. The studied dispersions were toxic to A. salina species. Meyer's solution, used as dilution water in the test, caused precipitation of Ag+ and also caused changes in CMC-stabilized AgNPs, changing the shape of the nanoparticles by depositing precipitates on their surface. These changes make the results of toxicity difficult to interpret. AgNPs stabilized with PVA remained unchanged. AgNPs affected cell division and caused the appearance of chromosomal aberrations on A. cepa. Higher numbers of chromosomal aberrations occurred in dispersions with smaller particle diameters (AgNPs3-PVA and AgNPs5-PVA, without dilution). In the studied conditions the dispersions were toxic to the tested organisms, the concentrations of precursors and the type of stabilizer used influenced the particle size and toxicity. In the test with A. cepa, the reconstituted hard water did not cause changes in the dispersions of AgNPs, whereas for A. salina the Meyer solution promoted aggregation of the particles and precipitation, in the dispersions stabilized with CMC, thus changing the samples.

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In this study, the cytotoxicity of different combinations of contemporary resin-based restoratives (adhesives, composites, luting agents) against human keratinocytes (HaCaT) was evaluated under two conditions, whether materials were applied to dentin or not. Adhesives (3-step etch-and-rinse/3ER: OptiBond FL; 2-step self-etch/2SE Clearfil SE Bond; Single Bond Universal/UNI), composites (conventional composite resin/CCR: Filtek Z350XT; flowable/FCR: Filtek Z350XT Flow; self-adhesive composite resin/SACR: Dyad Flow), and luting agents (conventional luting agent/CLA: Variolink-II; self-adhesive luting agent/SLA: RelyXU200) were combined according to their clinical use. Eluates from polymerized specimens applied to dentin were placed in contact with cells grown for 1 and 7 d. The controls were defined by cells without material contact. Cell viability was determined using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)] assay. C=C conversion was investigated using Fourier-transform infrared spectroscopy. After 1 d of incubation, when dentin was not present, 2SE yielded the highest cell viability, whereas 3ER, UNI, and SACR showed higher cell viability in the presence of dentin. After 7 d, when dentin was absent, 2SE and CLA achieved significantly higher cell viability. The presence of dentin resulted in a drastically higher cell viability for all materials, except 2SE and CLA. UNI had the lowest C=C conversion. The presence of dentin was a significant factor, which resulted in higher cell viability than what was seen for the material specimens per se. All materials resulted in a lower viability of HaCaT than what was seen under the no-material control conditions, with effects mainly limited to the first 24 h.

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