Ponzoni S.,State University Londrina
Neuroscience Letters | Year: 2012
The present study was designed to address the role of macrophages in Mn-induced neurotoxicity and to test the hypothesis that minocycline, a tetracycline derivative, attenuates the biochemical and morphological sequelae of Mn. Mn was unilaterally microinjected into rat nigra followed by systemic minocycline or saline administration 24. h later, daily for 3 days. At 72. h after the intranigral Mn microinjection, tyrosine hydroxylase immunostaining (TH-IS) was evaluated in the striatum, along with the number of macrophages (as indicated by CD11b immunostaining) in the substantia nigra. Mn significantly reduced striatal TH-IS, and causes an increased macrophage number at the lesion site when compared with the control group. The effects of Mn on striatal TH-IS and the number of macrophages at the lesion site were concentration dependent. Consistent with the stated hypothesis, minocycline significantly reduced the macrophage number in the lesion site and minimized the TH-IS striatal loss induced by Mn. These results indicate that an inflammatory response mediated by macrophages is induced by intranigral Mn microinjection, which is fully attenuated by minocycline treatment, suggesting that suppression of macrophage infiltration provides neuroprotection to dopaminergic neurons. © 2011 Elsevier Ireland Ltd.
Estanislau C.,State University Londrina
Psychology and Neuroscience | Year: 2012
Grooming behavior has been reported to be a response to novelty and other stressors. However, studies that sought to identify anxiety-related measures in the elevated plus-maze have not found grooming as a reliable index. Grooming has been implied with dearousal after a stressful experience.In the present work,a detailed investigation of this behavior was performed in a test with a longer duration (i.e., 10 min) than the usual duration in the elevated plus-maze. The level of anxiety was manipulated prior to the test by confining male rats to environments known to differ in the degree of aversive stimulation, including a familiar cage, a closed arm of the elevated plus-maze, and an open arm (i.e., the most aversive arm) of the elevated plus-maze. Grooming behavior was classified into three constituent elements: rostral grooming, head grooming, and body grooming. The groups were compared with regard to conventional measuresof the elevated plus-maze and grooming behavior. Prior confinement to an open arm led to a delayed effect of decreased open-arm exploration undetectable during the first half of the test compared with rats previously confined to a closed arm. Prior confinement to an open arm also increased the total duration of grooming during the second half of the test. These increases were found to be partially attributable to increases in the rostral element of grooming. The percentage of interrupted bouts was also found to discriminate the group previously confined to an open arm. These results indicate that prolongation of the session can reveal effects that are otherwise undetectable and that under such conditions some grooming measures can be useful in the evaluation of anxiety-like behavior.
Martins-Pinge M.C.,State University Londrina
Brazilian Journal of Medical and Biological Research | Year: 2011
The autonomic nervous system plays a key role in maintaining homeostasis under normal and pathological conditions. The sympathetic tone, particularly for the cardiovascular system, is generated by sympathetic discharges originating in specific areas of the brainstem. Aerobic exercise training promotes several cardiovascular adjustments that are influenced by the central areas involved in the output of the autonomic nervous system. In this review, we emphasize the studies that investigate aerobic exercise training protocols to identify the cardiovascular adaptations that may be the result of central nervous system plasticity due to chronic exercise. The focus of our study is on some groups of neurons involved in sympathetic regulation. They include the nucleus tractus solitarii, caudal ventrolateral medulla and the rostral ventrolateral medulla that maintain and regulate the cardiac and vascular autonomic tonus. We also discuss studies that demonstrate the involvement of supramedullary areas in exercise training modulation, with emphasis on the paraventricular nucleus of the hypothalamus, an important area of integration for autonomic and neuroendocrine responses. The results of these studies suggest that the beneficial effects of physical activity may be due, at least in part, to reductions in sympathetic nervous system activity. Conversely, with the recent association of physical inactivity with chronic disease, these data may also suggest that increases in sympathetic nervous system activity contribute to the increased incidence of cardiovascular diseases associated with a sedentary lifestyle.
Zaia D.A.M.,State University Londrina
International Journal of Astrobiology | Year: 2012
Amino acids and nucleic acid bases are very important for the living organisms. Thus, their protection from decomposition, selection, pre-concentration and formation of biopolymers are important issues for understanding the origin of life on the Earth. Minerals could have played all of these roles. This paper discusses several aspects involving the adsorption of amino acids and nucleic acid bases onto minerals under conditions that could have been found on the prebiotic Earth; in particular, we recommend the use of minerals, amino acids, nucleic acid bases and seawater ions in prebiotic chemistry experiments. Several experiments involving amino acids, nucleic acid bases, minerals and seawater ions are also suggested, including: (a) using well-characterized minerals and the standardization of the mineral synthesis methods; (b) using primary chondrite minerals (olivine, pyroxene, etc.) and clays modified with metals (Cu, Fe, Ni, Mo, Zn, etc.); (c) determination of the possible products of decomposition due to interactions of amino acids and nucleic acid bases with minerals; (d) using minerals with more organophilic characteristics; (e) using seawaters with different concentrations of ions (i.e. Na+, Ca2+, Mg2+, SO2 - 2- and Cl-); (f) using non-protein amino acids (AIB, α-ABA, β-ABA, γ-ABA and β-Ala and g) using nucleic acid bases other than adenine, thymine, uracil and cytosine. These experiments could be useful to clarify the role played by minerals in the origin of life on the Earth. Copyright © Cambridge University Press 2012.
Modesto K.A.,State University Londrina |
Martinez C.B.R.,State University Londrina
Chemosphere | Year: 2010
Roundup Transorb® (RDT) is a glyphosate-based herbicide containing a mixture of surfactants. The objective of this work was to evaluate the effects of this herbicide on the Neotropical fish Prochilodus lineatus. Juvenile fish were acutely exposed (6, 24 and 96h) to 1mgL-1 of RDT (RDT 1), 5mgL-1 of RDT (RDT 5) or only water (control) and blood samples for hematological analysis, liver for antioxidants analysis, and brain and muscle for acetylcholinesterase (AChE) determination, were collected. RDT effects were more evident in fish exposed to the higher concentration of the herbicide. Hematologic alterations appeared only after 96h exposure, when fish showed an increase in the hematocrit and in the number of both red and white blood cells. After 6h exposure fish showed a transient reduction in superoxide dismutase and catalase activity. RDT also inhibited glutathione-S-transferase, after 6 and 24h of exposure. The reduction in these enzymes is probably related to the occurrence of lipid peroxidation (LPO) in fish exposed to the herbicide for 6h. LPO returned to control levels after 24 and 96h exposure to RDT, when fish showed an increased activity of glutathione peroxidase. The content of reduced glutathione also increased after 96h exposure. Thus, after 24 and 96h the antioxidant defenses were apparently enough to combat ROS, preventing the occurrence of oxidative damage. The exposure to RDT for 96h led to an inhibition of AChE in brain and muscle at rates which may not be considered a life-threatening situation. © 2010 Elsevier Ltd.
Panis C.,State University Londrina
Advances in Protein Chemistry and Structural Biology | Year: 2014
Oxidative stress-driven modifications can occur in lipids, proteins, and DNA and form the basis of several chronic pathologies. The metabolites generated during oxidative responses consist of very reactive substances that result in oxidative damage and modulation of redox signaling as the main outcomes. Oxidative modifications occurring in proteins are poorly understood; among the several methods employed to study such modifications, the most promising strategies are based on proteomics approaches. Proteomics has emerged as one of the most powerful and sensitive analytical tools for mapping the oxidative changes present in proteins in a wide range of sample types and disease models. This chapter addresses the main aspects of redox processes, including an overview of oxidative stress and its biological consequences on proteins. Moreover, major proteomic strategies that can be employed as powerful tools for understanding protein oxidative modifications detected in chronic pathologies are discussed, highlighting cancer research as a model. © 2014 Elsevier Inc.
Santos T.G.,State University Londrina |
Martinez C.B.R.,State University Londrina
Chemosphere | Year: 2012
The effects of Atrazine, an herbicide used worldwide and considered as a potential contaminant in aquatic environments, were assessed on the Neotropical fish Prochilodus lineatus acutely (24 and 48h) exposed to 2 or 10μgL-1 of atrazine by using a set of biochemical and genetic biomarkers. The following parameters were measured in the liver: activity of the biotransformation enzymes ethoxyresorufin-O-deethylase (EROD) and glutathione S transferase (GST), antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), content of reduced glutathione (GSH), generation of reactive oxygen species (ROS) and occurrence of lipid peroxidation (LPO); in brain and muscle the activity of acetylcholinesterase (AChE) and DNA damage (comet assay) on erythrocytes, gills and liver cells. A general decreasing trend on the biotransformation and antioxidant enzymes was observed in the liver of P. lineatus exposed to atrazine; except for GR, all the other antioxidant enzymes (SOD, CAT and GPx) and biotransformation enzymes (EROD and GST) showed inhibited activity. Changes in muscle or brain AChE were not detected. DNA damage was observed in the different cell types of fish exposed to the herbicide, and it was probably not from oxidative origin, since no increase in ROS generation and LPO was detected in the liver. These results show that atrazine behaves as enzyme inhibitor, impairing hepatic metabolism, and produces genotoxic damage to different cell types of P. lineatus. © 2012 Elsevier Ltd.
Modesto K.A.,State University Londrina |
Martinez C.B.R.,State University Londrina
Chemosphere | Year: 2010
This work aimed to evaluate Roundup® effects on biochemical biomarkers of the neotropical fish Prochilodus lineatus. Fish were acutely exposed (6, 24 and 96 h) to 10 mg L-1 of Roundup® (RD) or only water (control) and samples of liver, for antioxidants analysis, and brain and muscle, for acetylcholinesterase (AChE) determination, were collected. Fish exposed to RD for 24 h showed reduction on superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, and increased glutathione (GSH) content. After 24 and 96 h, fish of RD group showed increased glutathione-S-transferase (GST) activity and lipid peroxidation. AChE activity was inhibited in brain after 96 h and in muscle after 24 and 96 h of exposure. Thus, acute exposure to RD stimulated the biotransformation pathway, with increased GST, but interfered on the antioxidant defenses, with reduction of SOD and GPx activity, leading to the occurrence of lipid peroxidation. Inhibition of AChE showed that RD acts as a contaminant with anti-AChE action. © 2009 Elsevier Ltd. All rights reserved.
Paulino E.T.,State University Londrina
Land Use Policy | Year: 2014
Although many contemporary studies of agriculture associate larger properties with higher relative productivity, this assumption has limited relevancy for the analysis of situations in which property owners profit more from large-scale property accumulation itself rather than any superiority in exploitation opportunities offered by increased size. In Brazil, the efficiency-of-scale paradigm has been used to criticize peasant agriculture as unproductive and hide contradictions deriving from land concentration. As this paper argues, however, small-scale agriculture is actually responsible for most of Brazil's food production, rural employment and agricultural income. The paper utilizes a land governance perspective to analyze the implementation of structural reforms aimed at turning back the land monopolization tide as well as efforts to weaken long-standing legal principles that socially condition individual property "rights" in Brazil. © 2013 The Author.
Youssef K.,Egyptian Plant Pathology Research Institute |
Roberto S.R.,State University Londrina
Postharvest Biology and Technology | Year: 2014
The efficacy of some potassium and calcium based salts, namely potassium sulphate (PS), potassium sorbate (PSo), potassium carbonate (PC), potassium bicarbonate (PB), calcium sulphate (CS), calcium chelate (CCh), calcium chloride (CC) and calcium silicate (CSi) against gray mold of 'Italia' table grapes, was evaluated. In in vitro experiments, PSo, PC, PB, and CCh completely inhibited mycelial growth of Botrytis cinerea at 0.25%. Under artificial inoculation, salts at 1% (immersed or sprayed) showed a variable effect against the pathogen. For natural infection, salt solutions (1%, w/v) were applied according to three strategies: (a) spray (one week) before harvest, (b) immersion after harvest, and (c) combined treatments spray and immersion. The decay incidence of gray mold was evaluated after 30 days at 2. ±. 1. °C and 90-95% RH, followed by 7 days of shelf-life at 22. ±. 2. °C. All tested salts significantly reduced the decay incidence of gray mold as compared to a water control for the three strategies. The percentages of reduction ranged between 77-100, 91-98, and 61-100% for the preharvest treatment, in combined application, and in the postharvest treatment, respectively. PB and PSo were the most effective salts, completely inhibiting development of gray mold when applied before harvest and as a postharvest treatment. The influence of salts on physical and chemical properties of berry quality including total soluble solids, titratable acidity, pH, color index, weight losses and microbiological profiles was also investigated. New strategies are needed with the critical goal of controlling gray mold of grapes with no fungicide residues. Salts applied just before harvest may be an effective way to minimize gray mold during storage. © 2013 Elsevier B.V.