Publications by authors named "Eduardo Alves Almeida"

Acute hypoxia is known to increase the generation of reactive oxygen species (ROS), leading to modulation in antioxidant defenses. Pollutant exposure can potentiate ROS generation during hypoxic events and impair antioxidant defenses, increasing the susceptibility of hypoxia-tolerant fishes, such as the Nile tilapia (Oreochromis niloticus), to oxidative stress. The purpose of this study was to evaluate oxidative stress responses of O.

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  • Pesticides from rice farming can harm non-target organisms, impacting biodiversity, leading researchers to study their presence in river water and their effects on Boana faber tadpoles.
  • The study found no major developmental issues in tadpoles but noted increased malondialdehyde (MDA) levels indicating oxidative stress after pesticide exposure, particularly with herbicide BTZ and fungicide TBZ.
  • Histological examinations revealed significant changes in the tadpoles, such as inflammation and liver enzyme activity alterations, highlighting the negative impact of rice pesticides on local aquatic ecosystems and biodiversity.
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Pesticides are released into the environment daily, and their effects on nontarget species in aquatic ecosystems have been widely reported. To evaluate the adverse effects caused in adults of Danio rerio species exposed to the pesticides abamectin, difenoconazole, and their commercial formulations (Kraft 36EC® and Score 250EC®), both isolated and in mixtures, biochemical biomarkers were analyzed in the gills of organisms exposed to sublethal concentrations. To this end, the activities of the enzymes 7-ethoxyresorufin-O-deethylase (EROD), glucuronosyltransferase (UDPGT), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), lipid hydroperoxide (LH), and malondialdehyde (MDA), which are indicative of oxidative stress, were measured after 48 h of exposure to the different pesticide treatments.

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Synthetic glucocorticoids are often found in surface waters and can cause harmful effects to aquatic organisms such as amphibians. In this work we evaluated the effects of the drugs prednisone (PD) and prednisolone (PL) on developmental, molecular, blood, biochemical and histological markers. Aquarana catesbeianus tadpoles were exposed for 16 days to environmentally relevant concentrations of 0, 0.

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This study aimed to assess the combined effect of hypoxia and exposure to diesel on biochemical parameters of Perna perna mussels. Mussels previously kept for 48 h in clean seawater were submitted to hypoxia for 24 h followed by reoxygenation in clean seawater for 48 h. The same procedure was done but using seawater containing 0.

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Rampant urbanization in coastal environments turns areas close to the seafront into a highly impacted ecosystem, possibly affecting the health and well-being of resident animal species. The tuco-tuco Ctenomys flamarioni is an endemic and endangered subterranean mammal from southern Brazil, and the anthropic influence was considered one of the main threats to the species. In this context, the present study aimed to investigate the patterns of oxidative status of the species in natural areas with different levels of anthropogenic disturbance.

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  • The study investigated how temperature (25 and 32 °C) influences the response of bullfrog tadpoles to different concentrations of the atrazine metabolite 2-hydroxyatrazine (2-HA) over 16 days.
  • The results showed that 2-HA reduced the activity of the enzyme superoxide dismutase (SOD) at 25 °C and caused liver and kidney damage, particularly affected by higher temperatures.
  • Overall, the findings suggest that environmentally relevant levels of 2-HA can impact biomarker responses and organ morphology in tadpoles, with temperature playing a significant role in these alterations.
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  • - The study investigated how ergothioneine (ERT) affects red blood cell adaptation by analyzing gene expression in specific signaling pathways during erythroid differentiation and oxidative stress using K562 cells.
  • - Two concentrations of ERT (1 nM and 100 µM) were tested with and without oxidative stress, revealing that lower concentration ERT significantly enhanced several protective gene expressions at different stages of cell differentiation.
  • - The findings suggest that ERT has a cytoprotective role mainly through the Nrf2-ARE pathway and potentially aids in red blood cell proliferation and differentiation via the FoxO3 pathway.
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  • * The study analyzed how MEL affects specific signaling pathways in K562 erythroleukemic cells when subjected to OS induced by hydrogen peroxide, by evaluating cell viability and gene expression.
  • * Results showed that MEL can restore Nrf2 levels and that different concentrations of MEL had distinct impacts on gene expression related to antioxidants and apoptosis, highlighting its potential as a therapeutic approach for diseases linked to oxidative stress.
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γ-aminobutyric acid (GABA) is one of the main neurotransmitters involved in the adaptation processes against the damage that hypoxia can cause to the brain. Due to its antagonist action on GABA receptors, the insecticide fipronil can turn the fish more susceptible to the negative effects of hypoxia. This study aimed to understand better if fipronil affects these GABAergic responses of Tilapia ahead to hypoxia.

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  • Disturbance in stream surroundings affects water quality and harms aquatic life, prompting a study on the impact of land use on fish biomarkers in Brazilian savanna streams.
  • The study focused on the Neotropical tetra fish, Astyanax lacustris, with fish exposed in cages across 13 streams during both dry and wet seasons, analyzing blood, liver, and gills for various biomarkers.
  • Findings revealed that increased anthropogenic disturbance correlated with genetic damage and reduced liver enzyme activity while also indicating negative impacts on water quality, suggesting that multibiomarker strategies can effectively assess the effects of landscape changes.
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Introduction: Schizophrenia is a complex psychiatric disorder that affects approximately twenty million people worldwide. Various factors have been associated with the physiopathology of this disease such as oxidative stress, which is an imbalance between pro-oxidant and antioxidant molecules.

Objective: This study evaluated the association between biomarkers of oxidative stress and response to pharmacological treatment among patients with schizophrenia in the context of their clinical information, demographic data, and lifestyle.

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  • Tebuthiuron (TBU) is a widely used herbicide in sugarcane fields that poses risks to aquatic life, particularly bullfrog tadpoles, due to its slow degradation and water solubility.
  • The study examined how varying temperatures (25 and 32 °C) affected the harmful impacts of TBU on bullfrog tadpoles, with increases in TBU concentration (0, 10, 50, and 200 ng/L) leading to significant changes in enzyme and gene activity related to metabolism and antioxidant defense.
  • The findings revealed that both TBU exposure and elevated temperature disrupted the tadpoles' metabolic balance, resulting in altered biomarker responses and liver damage, specifically at higher TBU concentrations
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In tropical climate countries, animal production faces a huge challenge, being the high solar irradiation levels an important factor that negatively influences the welfare and animal performance. The purpose of this research was to check the environment inside mobile shelters with different kinds of cover materials. This research has been developed at the State University of Goiás, Brazil, being used four different cover materials: DFPC, double-faced plastic canvas; PVC, polyvinyl chloride; VFB, tiles made with vegetable fiber and bitumen; and VFBW, tiles made with vegetable fiber and bitumen being the outer face painted white.

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Lubricant oils are among oil-based products that are not fully consumed during its use, thereby producing non-biodegradable residues which can cause contamination of natural systems. This study evaluated the toxicity of new and used lubricating oil (0.01 and 0.

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Increased malondialdehyde (MDA) levels are commonly considered an indicator of lipid peroxidation derived from oxidative stress insults promoted by exposure of fish to pollutants. However, a decrease in MDA levels after xenobiotic exposure has been also reported, an effect that is mostly attributed to enhanced antioxidant defenses. In this study, we assessed whether pollutant-mediated MDA decrease would be associated with antioxidant enhancement or with its metabolism by aldehyde dehydrogenase (ALDH) in the liver and gills of lambari (Astyanax altiparanae) exposed to diesel oil (0.

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Ocean acidification is a result of the decrease in the pH of marine water, caused mainly by the increase in CO released in the atmosphere and its consequent dissolution in seawater. These changes can be dramatic for marine organisms especially for oysters Crassostrea gasar if other stressors such as xenobiotics are present. The effect of pH changes (6.

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The occurrence of pharmaceuticals in the aquatic environment has increased considerably in the last decades, causing negative biochemical, physiological, and behavioral effects in aquatic organisms. In this study, we evaluated the effects of methylphenidate (MPH) on the aggressive behavior, dopamine-related gene transcript levels, monoamine levels, and carboxylesterase transcript levels and activity in the brain of male Nile tilapia (Oreochromis niloticus). Carboxylesterase activity was also measured in the liver and gills.

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This study investigated the effects of incubation period and melatonin treatment on red blood cell (RBC) metabolism in an auto-incubation model of HO-induced oxidative stress. The study was carried out on three healthy adult donors by incubating RBCs in their own plasma at 37 °C, or under the influence of 1 mM HO with and without 100 μM melatonin at different times (0, 1, 3 and 6 h). We assessed incubation period, treatment, as well as any interaction effects between these predictors on erythrocyte osmoregulation, hemolytic rate, oxidative stress markers, and adenylate nucleotide levels.

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Biochemical and molecular responses were evaluated in oysters Crassostrea brasiliana collected from three oyster farms, at Guaratuba Bay, southern Brazil, forming a pollutant gradient: Farm 1 (reference site - farther from the urban area), Farm 2 (intermediate site) and Farm 3 (nearest to the urban area). Oxidative stress markers, DNA damage and transcript levels of CYP2AU1, CYP2-like1, CYP2-like2, SULT-like, GPx-like, SOD-like, CAT-like, GSTmicrosomal-like, GSTomega-like, FABP-like and ALAd-like genes were analyzed in the gills. The levels of polycyclic aromatic hydrocarbons, linear alkylbenzenes and polychlorinated biphenyls were also evaluated in the soft tissues of the oysters and in the sediment of the Farms.

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Exposure of aquatic organisms to polycyclic aromatic hydrocarbons (PAH), such as phenanthrene (PHE), may increase the production of reactive oxygen species (ROS) and cause changes in the biotransformation systems. In addition, changes in water temperature can cause adverse effects in the organisms. Estuarine species, like the oyster Crassostrea brasiliana, can adapt and tolerate temperature variation.

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The pendulous crop is characterized by excessive distension of the crop musculature, compromising the bird's productivity and welfare. The etiology is still unknown, but it is believed that factors related to the birds' handling might be related to its incidence. The study was conducted in 2 environmental chambers.

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Purpose: Changes in the circadian rhythm may contribute to the development of cancer and are correlated with the high risk of breast cancer (BC) in night workers. Melatonin is a hormone synthesized by the pineal gland at night in the absence of light. Levels of melatonin and the metabolite of oxidative metabolism AFMK (acetyl-N-formyl-5-methoxykynurenamine), are suggested as potential biomarkers of BC risk.

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