Graphene oxide (GO) and reduced graphene oxide (rGO) are both widely applicable and there is a massive production throughout the world which imply in inevitable contamination in the aquatic environment by their wastes. Nevertheless, information about their interaction at the cellular level in fish is still scarce. We investigated the metabolic activity, reactive oxygen species (ROS) production, responses of antioxidant defenses, and total antioxidant capacity (TAC) as well as oxidative stress and DNA integrity in zebrafish liver cells (ZFL) exposed to (0.
View Article and Find Full Text PDFGraphene oxide (GO) and reduced graphene oxide (rGO) are carbon-based nanomaterials that have a wide range of applicability. Therefore, it is expected that their residual traces reach the aquatic environment, accumulate, and interact with its different compartments and the biota living in them. The concentration- and time-dependency response to GO and rGO in aquatic organisms are still poorly known.
View Article and Find Full Text PDFObjective: The study evaluates psychological responses to the COVID-19 outbreak in the students, professors, and staff due to the social distancing and transition of the classroom activities through online learning.
Methods: 518 participants from a University community in Brazil answered an online survey with questions related to demographic data, psychological responses, and preventive measures. Absolute and relative frequencies described the sample, Chi-square and z-test tested associations between the variables, adopting p<0.
Gold nanorods (AuNRs) are rod-shaped nanoparticles (NPs) with special optical properties that allow their application in several areas including photothermal therapy, diagnosis, drug and gene delivery, cellular imaging, and biosensors. Their high potential for many applications increases the possibility of release in aquatic environments, which can cause risks to organisms. In this study, we evaluated toxic effects of AuNRs on cladoceran and fish (Ceriodaphnia dubia and Danio rerio) and their recovery after post-exposure periods.
View Article and Find Full Text PDFPathogen interactions with the host immune response components are critical for establishing protective immunity and pathological responses against Leishmania parasites. A predominant proinflammatory profile associated with enhanced phagocytosis trigger a cell-mediated immune response that is relevant to infection control. On the other hand, an anti-inflammatory phenotype, correlated with a predominant modulated/regulatory response, favors intracellular proliferation of Leishmania parasites and disease progression.
View Article and Find Full Text PDFCopper oxide nanoparticles (CuO NP) have been produced on a large scale due to their economically interesting thermophysical properties. This heightens the concern about risks they may pose on their release into the environment, possibly affecting non-target organisms. Microalga are important organisms in ecotoxicological studies as they are at the base of the aquatic food chain, but information about their biochemical and photosynthetic changes in response CuO NP are still scarce.
View Article and Find Full Text PDFAedes aegypti is the vector of important diseases like dengue, zika, chikungunya, and yellow fever. Vector control is pivotal in combating the spread of these mosquito-borne illnesses. Photoactivable larvicide curcumin obtained from Curcuma longa Linnaeus has shown high potential for Ae.
View Article and Find Full Text PDFNanoparticles (NPs) production is increasing worldwide. These products are likely to end up in aquatic environments. However, few studies evaluated the chronic toxicity of iron-based NPs (Fe-NPs) to cladocerans and their potential ecotoxicological hazards.
View Article and Find Full Text PDFGraphene oxide (GO) is a carbon nanomaterial with specific properties, which allow its use in several areas. Some studies have characterized the effects of GO on aquatic organisms, but the ability of recovery after exposure remains largely unknown. In this study, we evaluated the effects of GO on the antioxidant metabolism of zebrafish after 48 h of sub-lethal exposure, and the fish recovery after 168 h in nanoparticle-free water.
View Article and Find Full Text PDFThe increase of production and consumption of copper oxide nanostructures in several areas contributes to their release into aquatic ecosystems. Toxic effects of copper oxide nanoparticles (CuO NPs), in particular, on tropical aquatic organisms are still unknown, representing a risk for biota. In this study, the effects of rod-shaped CuO NPs on the Neotropical species Ceriodaphnia silvestrii and Hyphessobrycon eques were investigated.
View Article and Find Full Text PDFThe unique physico-chemical properties of nanomaterials have allowed their application in different areas including electronics, energy storage, nanomedicine, environmental remediation and biotechnology. Graphene and its derivatives, in particular, have been commercially available, with prediction for increasing their production in the next years, in a way that their release into aquatic environments is very likely to occur, and the impacts of such situation on organisms are still not completely understood. In this context, we evaluated graphene oxide (GO) effects on the freshwater cladoceran Ceriodaphnia dubia through acute and chronic toxicity, feeding rates, and reactive oxygen species (ROS) generation.
View Article and Find Full Text PDFProbiotics Antimicrob Proteins
December 2017
Several studies have demonstrated a diversity of bacterial species in human milk, even in aseptically collected samples. The present study evaluated potential probiotic bacteria isolated from human milk and associated maternal variables. Milk samples were collected from 47 healthy women and cultured on selective and universal agar media under aerobic and anaerobic conditions.
View Article and Find Full Text PDFGraphene exhibits unique physical and chemical properties that facilitate its application in many fields, including electronics and biomedical areas. However, the use of graphene and its derivatives could result in accumulation in aquatic environments, and the risks posed by these compounds for organisms are not completely understood. In this study, we investigated the effects of graphene oxide (GO) on adult zebrafish (Danio rerio).
View Article and Find Full Text PDFJ Environ Sci Health B
September 2013
This study aimed to estimate the acute toxicity of teflubenzuron (1-(3,5-dichloro-2,4-difluorophenyl)-3-(2,6-difluorobenzoyl)urea) (TFB) for Daphnia magna, Lemna minor and Poecilia reticulata, in the absence and presence of sediment; evaluate the effect of sediment on the TFB bioavailability; and to classify this insecticide according to its environmental poisoning risk for agricultural and aquaculture uses. The tests of TFB acute toxicity were conducted in static system in a completely randomized design with increasing TFB concentrations, and a control group. The TFB has been classified according to the estimated values of EC50 and LC50 by its acute toxicity and environmental risk.
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