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The presence of plastic waste in our environment has continued growing and become an important environmental concern. Because of its degradation into micro- and nanoplastics (MNPLs), MNPLs are becoming environmental pollutants of special environmental/health concern. Since ingestion is one of the main exposure routes to MNPLs, the potential effects of digestion on the physicochemical/biological characteristics of polystyrene nanoplastics (PSNPLs) were determined. The results indicated a high tendency of digested PSNPLs to agglomerate and a differential presence of proteins on their surface. Interestingly, digested PSNPLs showed greater cell uptake than undigested PSNPLs in all three tested cell lines (TK6, Raji-B, and THP-1). Despite these differences in cell uptake, no differences in toxicity were observed except for high and assumed unrealistic exposures. When oxidative stress and genotoxicity induction were determined, the low effects observed after exposure to undigested PDNPLs were not observed in the digested ones. This indicated that the greater ability of digested PSNPLs to internalize was not accompanied by a greater hazard. This type of analysis should be performed with other MNPLs of varying sizes and chemical compositions.

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In the present work, silver nanoparticles (AgNPs) synthetized with Cryptocarya alba (Peumo) leaf extract were studied. The fabrication method was fast, low cost, and eco-friendly, and the final properties of AgNPs were determined by experimental parameters, such as AgNO3 and Peumo extract concentrations used. Setting suitable experimental conditions, crystalline AgNPs with apparent spherical forms and average diameter around 3.5 nm were obtained. In addition, the capability of synthesized Peumo-AgNPs to remove methylene blue dye (MB) in aqueous solution as well as their catalytic effectiveness was also investigated. The results showed that green synthesized AgNPs can remove fast and effectively the MB dye from aqueous medium by itself, but better results were found acting like catalyst by using sodium borohydride (NaBH4) in the reaction. In addition, this green nanomaterial can be recycling several times maintaining initial properties for removal of MB. Thus, AgNPs synthetized with Peumo leaf extracts could be an excellent catalyst candidate for degradation of blue methylene dye in chemical industries.

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Copper and nickel nanoparticles (Cu-NPs and Ni-NPs, respectively) are used in a variety of industrial applications, such as semiconductors, catalysts, sensors, and antimicrobial agents. Although studies on its potential genotoxicity already exist, few of them report in vivo data. In the present study we have used the wing-spot assay in Drosophila melanogaster to determine the genotoxic activity of Cu-NPs and Ni-NPs, and these data have been compared with those obtained with their microparticle forms (MPs). Additionally, a complete physical characterization of NPs using transmission electronic microscopy (TEM), dynamic light scattering (DLS), and laser Doppler velocimetry (LDV) techniques was also performed. Results obtained with Cu-NPs and Cu-MPs indicate that both failed to induce an increase in the frequency of mutant spots formation in the wings of the adults, suggesting a lack of genotoxicity in somatic cells of D. melanogaster. However, when Ni-NPs and Ni-MPs were evaluated, a significant increase of small single spots and total mutant spots was observed only for Ni-NPs (P<0.05) at the highest dose assessed. Thus, the genotoxicity of Ni-NPs seem to be related to their nanoscale size, because no genotoxic effects have been reported with their microparticles and ions. This study is the first assessing the in vivo genotoxic potential of Cu-NPs and Ni-NPs in the Drosophila model.

RESUMO

Resumen OBJETIVO Determinar el perfil de expresión de los miRNA-21, -106, -126 y -146 y la cuantificación de IL-1β en el suero de pacientes embarazadas sanas, a término, con y sin trabajo de parto activo y en pacientes con evidencias clínicas de corioamnionitis. MATERIALES Y MÉTODOS Estudio analítico, longitudinal y prolectivo efectuado en pacientes que ingresaron para control, seguimiento obstétrico y terminación del embarazo al Instituto Nacional de Perinatología de la Ciudad de México entre febrero de 2015 y agosto de 2016. Variables de estudio: pacientes embarazadas sanas, a término, con y sin trabajo de parto activo y pacientes con evidencias clínicas de corioamnionitis, edad materna y semanas de gestación. A cada paciente se le tomaron cinco mililitros de sangre periférica para centrifugación y recuperación de suero. La obtención del ARN se efectuó a partir de 500 µL de suero, al que se añadió el mismo volumen del reactivo de TRIzol. El cADN se sintetizó a partir de 3 ng de ARN mediante el ensayo de retrotranscripción. La expresión de los miRNAs se efectuó mediante reacción en cadena de la polimerasa (PCR) con iniciadores específicos. Los resultados se reportan en media ± desviación estándar y el análisis estadístico se llevó a cabo mediante la prueba de Mann-Whitney, con una diferencia significativa de p < 0.05. RESULTADOS Se estudiaron 45 pacientes embarazadas que se dividieron en tres grupos: 1) pacientes sanas a término, sin trabajo de parto activo (n = 15); 2) pacientes con trabajo de parto activo (n = 15); y 3) pacientes con evidencias clínicas de corioamnionitis (n = 15). En las embarazadas sanas, con trabajo de parto activo, el perfil de expresión del miR-126 se incrementó 1.23 veces (p ≤ 0.001) en tanto que el miR-21 y miR-146 disminuyeron 2.1 ( p ≤ 0.001) y 0.73 veces (p ≤ 0.001), respectivamente, y la concentración de IL-1β se incrementó 1.8 veces (p = 0.014) en relación con las pacientes sanas sin trabajo de parto. El perfil de expresión de estos miRNAs y de IL-1β cambió en las pacientes con evidencias clínicas de corioamnionitis. El miR-126 y miR-146 se incrementaron 1.31 (p ≤ 0.001) y 1.1 veces (p = 0.05); en tanto que el miR-21 disminuyó 1.4 veces (p ≤ 0.05) y la concentración de la IL-1β se incrementó 2.8 veces (p = 0.002) con respecto a las pacientes sin trabajo de parto activo. El miR-106 no mostró diferencias significativas entre los tres grupos de estudio. CONCLUSIONES En su conjunto, los resultados de este ensayo sugieren que el perfil de expresión entre miR-21, miR-126 y miR-146 podría considerarse marcador molecular de corioamnionitis. Para que esto pueda tomarse como patrón de referencia deberán emprenderse más ensayos que corroboren este patrón y evalúen su eficacia.

Abstract OBJECTIVE To determine the expression profile of miRNA-21, -106, -126 and -146 and to quantify the secretion of IL-1β in the serum of healthy pregnant patients at term with and without active labor and in patients with clinical evidences of chorioamnionitis. MATERIALS AND METHODS Analytical, longitudinal, and prolective study carried out in patients admitted for control, obstetric, and pregnancy resolution into the National Institute of Perinatology in Mexico City between February 2015 and August 2016. Study variables: healthy pregnant patients at term with and without active labor and patients with clinical evidence of chorioamnionitis, maternal and gestational age. Five milliliters of peripheral blood were taken from each patient, which was centrifuged, and the serum recovered. RNA was obtained from 500 μL of serum to which the same volume of TRIzol reagent was added. The cDNA was synthesized with 3 ng of RNA by the reverse transcription assay. The expression of the microRNAs was performed by polymerase chain reaction (PCR) with specific primers. The results are presented as mean ± standard deviation and statistical analysis was performed using the Mann-Whitney test with a significant difference of p<0.05. RESULTS In healthy pregnant patients with active labor, it was observed that the expression profile of miR-126 increased 1.23-fold (p≤0.001); while the miR-21 and miR-146 decreased 2.1- (pp≤0.001) and 0.73-fold (p≤0.001) respectively and the concentration of IL-1β increased 1.8-fold (p = 0.014) with respect to the healthy patients without labor. The expression profile of these miRNAs and IL-1β change in patients with clinical evidence of chorioamnionitis. The miR-126 and miR-146 increased 1.31- (p≤0.001) and 1.1-fold (p = 0.05); while miR-21 decreased 1.4-fold (p≤0.05) and the concentration of IL-1β increased 2.88-fold (p = 0.002) with respect to patients without active labor. The miR-106 did not show significant differences between the three study groups. CONCLUSIONS These results suggest that miRNA-21, -126 and -146 could be considered as molecular markers in the development of chorioamnionitis; however, more tests should be carried out to corroborate this pattern and evaluate its efficiency.