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Oxidative stress has long been postulated to play an essential role in aging mechanisms, and numerous forms of molecular damage associated with oxidative stress have been well documented. However, the extent to which changes in gene expression in direct response to oxidative stress are related to actual cellular aging, senescence, and age-related functional decline remains unclear. Here, we ask whether H2O2-induced oxidative stress and resulting gene expression alterations in prostate epithelial cells in vitro reveal gene regulatory changes typically observed in naturally aging prostate tissue and age-related prostate disease. While a broad range of significant changes observed in the expression of non-coding transcripts implicated in senescence-related responses, we also note an overrepresentation of gene-splicing events among differentially expressed protein-coding genes induced by H2O2. Additionally, the collective expression of these H2O2-induced DEGs is linked to age-related pathological dysfunction, with their protein products exhibiting a dense network of protein-protein interactions. In contrast, co-expression analysis of available gene expression data reveals a naturally occurring highly coordinated expression of H2O2-induced DEGs in normally aging prostate tissue. Furthermore, we find that oxidative stress-induced DEGs statistically overrepresent well-known senescence-related signatures. Our results show that oxidative stress-induced gene expression in prostate epithelial cells in vitro reveals gene regulatory changes typically observed in naturally aging prostate tissue and age-related prostate disease.

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An artificial neural network (ANN) hybrid structure was proposed that, unlike the standard ANN structure optimization, allows the fit of several adsorption curves simultaneously by indirectly minimizing the real output error. To model a case study of 3-aminophenol adsorption phenomena onto avocado seed activated carbon, a hybrid ANN was applied to fit the parameters of the Langmuir and Sips isotherm models. Network weights and biases were optimized with two different methods: particle swarm optimization (PSO) and genetic algorithm (GA), due to their good convergence in large-scale problems. In addition, the data were also fitted with the Levenberg-Marquardt feedforward optimization method to compare the performance between a standard ANN model and the hybrid model proposed. Results showed that the ANN-isotherm hybrid models with both PSO and GA were able to accurately fit the experimental equilibrium adsorption capacity data using the Sips isotherm model, obtaining Pearson's correlation coefficient (R) of the order of 0.9999 and mean squared error (MSE) around 0.5, very similar to the performance of standard ANN using Levenberg-Marquardt optimization. On the other hand, the results with Langmuir isotherm models were quite inferior in the ANN-isotherm hybrid models with both PSO and GA, with R and MSE of around 0.944 and 4.04 × 102, respectively. The proposed ANN-isotherm hybrid structure was successfully applied to estimate the parameters of adsorption isotherms, reducing the computational demand and the exhausting task of estimating the parameters of each adsorption curve individually.

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Parabens (alkyl-p-hidroxybenzoates) are antimicrobial preservatives used in personal care products, classified as an endocrine disruptor, so they are considered emerging contaminants. A raw version of activated carbons obtained from African palm shell (Elaeis guineensis) modified chemically by impregnation with salts of CaCl2 (GC2), MgCl2 (GM2) and Cu(NO3)2 (GCu2) at 2% wt/v and carbonized in CO2 atmosphere at 1173 K was prepared. The process of adsorption of methyl (MePB) and ethylparaben (EtPB) from aqueous solution on the activated carbons at 18 °C was studied and related to the interactions between the adsorbate and the adsorbent, which can be quantified through the determination of immersion enthalpies in aqueous solutions of corresponding paraben, showing the lowest-value carbon GM2, which has a surface area of 608 m2 × g-1, while the highest values correspond to the activated carbon GCu2, with a surface area of 896 m2 × g-1 and the highest content of surface acid sites (0.42 mmol × g-1), such as lactonic and phenolic compounds, which indicates that the adsorbate-adsorbent interactions are favored by the presence of these, with interaction enthalpies that vary between 5.72 and 51.95 J × g-1 for MePB adsorption and 1.24 and 52.38 J × g-1 for EtPB adsorption showing that the process is endothermic.

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Resumen Se evaluó la aminación de un carbón activado preoxidado con ácido nítrico en la adsorción de 4-nitrofenol. Se aplicó el modelo de Sips a la adsorción desde solución acuosa, utilizando Sigmoidal Logistic 3 Parameter del programa SigmaPlot 12. Los parámetros obtenidos se compararon con los calculados con el programa Statistica 7 para los modelos de Sips y Langmuir. Se encontró que la modificación realizada sobre el carbón activado incrementó la adsorción de 4-nitrofenol de 2,16 a 2,19 mmolg-1, aumentando, a su vez, la afinidad adsorbente-adsorbato. El parámetro para la energía característica del sistema determinado con el modelo de Langmuir toma un valor de 377,47 L mmol-1 al no considerar la heterogeneidad energética, mientras que a partir del modelo de Sips se presenta un valor de 8,32 (Lmmol-1)1/n. Adicionalmente, se encontró que en la ecuación matemática Sigmoidal Logistic 3 Parameter del programa SigmaPlot el valor de 1/x0 corresponde a la constante KLF del modelo Langmuir-Freundlich, mientras que el valor del parámetro Ks del modelo de Sips es igual a (1/x0)-b. Se concluye que la adsorción de 4-nitrofenol sobre el carbón activado se favorece por el incremento de grupos nitrogenados sobre su superficie.

Abstract The amination of a nitric acid pre oxidized activated carbon in the adsorption of 4-nitrophenol was evaluated. The Sips model application to the aqueous solution adsorption data, using Sigmoidal Logistic 3 Parameter formula, in the SigmaPlot 12 program was applied. The obtained parameters were compared with those calculated with Statistica 7 program for Sips and Langmuir models. It was found that the activated carbon increases the adsorption from 2.16 to 2.19 mmol g-1, showing good adsorbent-adsorbate affinity. The system's characteristic energy parameter calculated with the Langmuir model was 377.47 L mmol-1, when not considering energy heterogeneity, while from the Sips model was 8.32 (L.mmol-1)1/n. Additionally, it was found that in the mathematical equation Sigmoidal Logistic 3 Parameter of the SigmaPlot program, the 1/x0 value corresponds to the Langmuir-Freundlich model constant KLF, while the parameter value KS in the Sips model is equal to (1/x0)-b in this program. It was concluded that the 4-nitrophenol adsorption on activated carbon is favored by the presence of nitrogen groups on their activated carbon surface.

Resumo Foi avaliada a aminação de um carvão ativado preoxidado com ácido nítrico na adsorção do 4-nitrofenol. Foi aplicado o modelo de Sips à adsorção desde solução aquosa usando Logística Sigmoidal 3 do programa Sigmaplot 12. Os parâmetros obtidos foram comparados com os calculados com o programa Statistica 7, para os modelos de Sips e Langmuir. Foi encontrado que a modificação do carvão ativado incrementou a adsorção de 4-nitrofenol de 2,16 até 2,19 mmolg-1, acrescentando a afinidade adsorvente-adsorvato. O parâmetro para a energia característica do sistema calculado com o modelo Langmuir teve um valor de 377,47 Lmmol-1 porque não considerou a heterogeneidade energética, enquanto que no modelo de Sips este parâmetro teve um valor de 8,32 (Lmmol-1)1/n. Além disso, foi encontrado que na equação matemática Sigmoidal Logistic 3 Parameter do programa Sigmaplot 3 o valor de 1/x0 corresponde à constante KLF do modelo Langmuir-Freundlich, enquanto o valor do parâmetro KS do modelo de Sips é igual a (1/x0)-b. Conclui-se que a adsorção do 4-nitrofenol sobre carvão ativado é favorecida pela presença de grupos nitrogenado na superfície destes.

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Mycoplasma hyopneumoniae is an economically significant swine pathogen that causes porcine enzootic pneumonia (PEP). Important processes for swine infection by M. hyopneumoniae depend on cell surface proteins, many of which are secreted by secretion pathways not completely elucidated so far. A putative type I signal peptidase (SPase I), a possible component of a putative Sec-dependent pathway, was annotated as a product of the sipS gene in the pathogenic M. hyopneumoniae 7448 genome. This M. hyopneumoniae putative SPase I (MhSPase I) displays only 14% and 23% of sequence identity/similarity to Escherichia coli bona fide SPase I, and, in complementation assays performed with a conditional E. coli SPase I mutant, only a partial restoration of growth was achieved with the heterologous expression of a recombinant MhSPase I (rMhSPase I). Considering the putative surface location of MhSPase I and its previously demonstrated capacity to induce a strong humoral response, we then assessed its potential to elicit a cellular and possible immunomodulatory response. In assays for immunogenicity assessment, rMhSPase I unexpectedly showed a cytotoxic effect on murine splenocytes. This cytotoxic effect was further confirmed using the swine epithelial PK(15) cell line in MTT and annexin V-flow cytometry assays, which showed that rMhSPase I induces apoptosis in a dose dependent-way. It was also demonstrated that this pro-apoptotic effect of rMhSPase I involves activation of a caspase-3 cascade. The potential relevance of the rMhSPase I pro-apoptotic effect for M. hyopneumoniae-host interactions in the context of PEP is discussed.

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