Ethanol is a central nervous system depressant that is widely consumed worldwide. When consumed chronically, it may have several consequences to the organism, such as oxidative stress. Ethanol metabolism increases the production of oxidant molecules and its consumption may cause changes in enzymatic and non-enzymatic systems that maintain cellular homeostasis. The activity of endogenous enzymes and lipid peroxidation are altered in alcohol consumers. Therefore, this study aimed to evaluate oxidative stress parameters in ethanol users compared to a control group. For that, the activity of the enzymes superoxide dismutase, catalase, and glutathione peroxidase, the ferric reducing/antioxidant power (FRAP), and malondialdehyde were evaluated. The influence of the amount of ethanol consumed on the analyzed parameters was also verified. The group of alcohol users consisted of 52 volunteers, 85% male and 15% female, with a mean age of 41±13 years. The control group consisted of 50 non-drinkers, 40% male and 60% female, with a mean age of 50±10 years. There was a significant difference in superoxide dismutase (P<0.001) and malondialdehyde (P=0.007) measurements between groups, as both parameters were increased in the group of ethanol users. Because of the higher amount of ethanol consumed, there was an increase of the catalase activity parameters and gradual reduction of FRAP. Thus, the ethanol-consuming participants were most likely under oxidative stress.

Resumo Bisfenol A (BPA) é um contaminante emergente regularmente detectado em ecossistemas aquáticos, é considerado um agente modificador endócrino (EDC). Além disso, outro produto químico relacionado com atividade humana, encontrado com frequência nas águas superficiais, é a cafeína. O objetivo deste estudo foi avaliar a ocorrência de risco ecotoxicológico devido a BPA e cafeína em amostras de água da Bacia Hidrográfica do Rio Sinos, Rio Grande do Sul, Brasil. Foram coletadas amostras de água em três locais mensalmente no período de 9 de maio de 2016 a 11 de abril de 2017 (n = 36). As concentrações de BPA em amostras de água coletadas estavam na faixa de não detectada a 517 ng L-1 e concentrações de cafeína na faixa de 41,7 a 28,439,6 ng L-1. A concentração de BPA nas amostras analisadas apresentou correlação moderada com a cafeína (rs = 0,402). Alto risco ecotoxicológico para BPA foi caracterizado em 77,77% das amostras, com 11,11% apresentando médio e 11,1% apresentando baixo risco. Para cafeína 13,9%, 50% e 36,11% das amostras apresentaram risco alto, médio e baixo, respectivamente. Concentrações de cafeína em água podem ser utilizadas como preditoras de concentrações de BPA acima de 10 ng L-1, menor concentração de risco ecotoxicológico, com especificidade de 66,7% e sensibilidade de 70,4%. A avaliação dos riscos aquáticos revelou que ambos os compostos investigados representam risco para os organismos nas águas superficiais estudadas, foz do arroio Pampa, foz do arroio Luiz Rau e ponto de captação para abastecimento público em Lomba Grande.

Abstract Bisphenol A (BPA) is an emerging contaminant, regularly detected in aquatic ecosystems, considered as an endocrine disrupting compound (EDC). Caffeine is another chemical related to human activity, often found in surface waters. The objective of this study was to evaluate the ecotoxicological risk due to BPA and caffeine in water samples from the Sinos River basin, Rio Grande do Sul, Brazil. Water samples were collected at three sites monthly from May 9 th, 2016 to April 11th, 2017 (n = 36). BPA concentrations in water samples collected were in the range of not detected to 517 ng L-1 and caffeine concentrations in the range of 41.7 to 28,439.6 ng L-1. The concentration of BPA in the analyzed samples had a moderate correlation with caffeine (rs = 0.402). High ecotoxicological risk for BPA was characterized in 77.77% of samples, with 11.11% presenting medium and 11.1% presenting low risk. For caffeine 13.9%, 50% and 36.11% of the samples presented high, medium and low risk, respectively. Caffeine concentrations in water can be used as predictors of BPA concentrations above 10 ng L-1, the lower concentration of ecotoxicological risk, with specificity of 66.7% and sensitivity of 70.4%. The assessment of aquatic risks has shown that both investigated compounds pose risks to organisms in the studied surface waters, mouth of the Pampa stream, mouth of the Luiz Rau stream and catchment point for public supply in Lomba Grande.

<p>A preservação dos recursos hídricos está diretamente relacionada ao monitoramento da contaminação fecal, no intuito de possibilitar o desenvolvimento de estratégias apropriadas para a gestão das fontes poluidoras. No presente estudo, vinte e cinco amostras de água de seis pontos de captação de água para abastecimento público foram utilizadas para análise da presença de cafeína, de coliformes totais e de coliformes termotolerantes. Cafeína foi detectada em todas as amostras coletadas nos diferentes locais de amostragem, com intervalo de concentração entre 0,15 ng mL^–1 e 16,72 ng mL^–1. Coliformes totais foram detectados em todas as amostras analisadas, com concentrações variando de 52 NMP/100 mL a concentrações maiores que 24196 NMP/100 mL, enquanto a faixa de variação de concentração de coliformes termotolerantes variou de menos de 1 NMP/100 mL a 7800 NMP/100 mL. Não foi verificada correlação significativa entre coliformes totais e cafeína (rs = 0.35, p = 0.09), no entanto foi observada correlação moderada entre coliformes termotolerantes e cafeína (rs = 0.412, p <0.05), o que pode indicar uma provável fonte humana destas bactérias. A determinação de cafeína em amostras de água pode ser uma ferramenta útil para avaliar a contaminação com resíduos fecais humanos.</p>

<p>The preservation of hydric resources is directly related to fecal contamination monitoring, in order to allow the development of strategies for the management of polluting sources. In the present study, twenty-five water samples from six water public supply collection sites were used for the evaluation of the presence of caffeine, total and fecal coliforms. Caffeine was detected in all samples, with concentrations ranging from 0.15 ng mL^–1 to 16.72 ng mL^–1. Total coliforms were detected in all samples, with concentrations in the range of 52 NMP/100 mL to higher than 24196 NMP/100 mL, whether the concentration range for fecal coliforms was in the range of below 1 NMP/100 mL to 7800 NMP/100 mL. No significant correlation was found between total coliforms and caffeine concentrations (rs = 0.35, p = 0.09). However, a moderate correlation between fecal coliforms and caffeine concentrations was found (rs = 0.412, p <0.05), probably indicating a human source for these bacteria. Caffeine determination in water may be a useful strategy to evaluate water contamination by human fecal waste.</p>

We examined the degeneration of post-mitotic ganglion cells in ex-vivo neonatal retinal explants following axon damage. Ultrastructural features of both apoptosis and autophagy were detected. Degenerating cells reacted with antibodies specific for activated caspase-3 or -9, consistent with the presence of caspase activity. Furthermore, peptidic inhibitors of caspase-9, -6 or -3 prevented cell death (100 µM Ac-LEDH-CHO, 50 µM Ac-VEID-CHO and 10 µM Z-DEVD-fmk, respectively). Interestingly, inhibition of autophagy by 7-10 mM 3-methyl-adenine increased the rate of cell death. Immunohistochemistry data, caspase activation and caspase inhibition data suggest that axotomy of neonatal retinal ganglion cells triggers the intrinsic apoptotic pathway, which, in turn, is counteracted by a pro-survival autophagic response, demonstrated by electron microscopy profiles and pharmacological autophagy inhibitor.

Exclusion of the transcription factor Max from the nucleus of retinal ganglion cells is an early, caspase-independent event of programmed cell death following damage to the optic axons. To test whether the loss of nuclear Max leads to a reduction in neuroprotection, we developed a procedure to overexpress Max protein in rat retinal tissue in vivo. A recombinant adeno-associated viral vector (rAAV) containing the max gene was constructed, and its efficiency was confirmed by transduction of HEK-293 cells. Retinal ganglion cells were accessed in vivo through intravitreal injections of the vector in rats. Overexpression of Max in ganglion cells was detected by immunohistochemistry at 2 weeks following rAAV injection. In retinal explants, the preparation of which causes damage to the optic axons, Max immunoreactivity was increased after 30 h in vitro, and correlated with the preservation of a healthy morphology in ganglion cells. The data show that the rAAV vector efficiently expresses Max in mammalian retinal ganglion cells, and support the hypothesis that the Max protein plays a protective role for retinal neurons.

Programmed cell death in the form of apoptosis involves a network of metabolic events and may be triggered by a variety of stimuli in distinct cells. The nervous system contains several neuron and glial cell types, and developmental events are strongly dependent on selective cell interactions. Retinal explants have been used as a model to investigate apoptosis in nervous tissue. This preparation maintains the structural complexity and cell interactions similar to the retina in situ, and contains cells in all stages of development. We review the finding of nuclear exclusion of several transcription factors during apoptosis in retinal cells. The data reviewed in this paper suggest a link between apoptosis and a failure in the nucleo-cytoplasmic partition of transcription factors. It is argued that the nuclear exclusion of transcription factors may be an integral component of apoptosis both in the nervous system and in other types of cells and tissues.