Publications by authors named "Marcelo Veiga"

Article Synopsis
  • The study investigates the effects of free and nanoencapsulated benznidazole on the inflammatory response and overall health of mice infected with a parasite, focusing on the role of the cholinergic system in immune regulation.
  • * The results show that while both treatments reduced parasite levels and improved blood conditions like anemia and thrombocytopenia, they did not completely eliminate the infection.
  • * Analysis reveals that benznidazole triggers changes in cholinergic signaling and results in significant inflammation and organ damage, but ultimately helps reverse some of the infection-related health issues in the test subjects.
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The objective of this study is to gain an understanding of the development of consciousness and its relationship with education based on different theoretical models-namely those by Piaget, Vygotsky and Steiner. All three of them focus on different subcomponents of the educational process and there is hence a need for integrative discussion. Piaget and Vygotsky are fundamental references in the understanding of developmental and learning processes.

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This study aimed to identify the regions of the body surface of silver catfish () with a higher population of mucous cells in the skin. Additionally, the effects of stressful conditions, such as different stocking densities and food deprivation, on the proliferative response of mucous cells in the skin and gill epithelium and their impact on cutaneous mucous lysozyme activity were investigated. Silver catfish were divided into four experimental groups: high stocking density (32 kg/m) and fed (HSD-F), high stocking density and fasted (HSD-FS), low stocking density (2.

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Chagas Disease (CD) affects around eight million people worldwide. It is considered a neglected disease that presents few treatment options with efficacy only in the acute phase. Nanoparticles have many positive qualities for treating parasite infections and may be effectively and widely employed in clinical medicine.

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We hypothesized that norbixin, which is a carotenoid used as an orange/red natural food coloring additive, has anti-atherogenic properties. An in vitro oxidation assay with human LDL and a rabbit model of atherosclerosis were used to test this hypothesis. Norbixin inhibited the oxidation of isolated human LDL in a concentration-dependent manner.

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The morphological similarities of vertebrates' embryonic development are used as a criterion for choosing animal models that can be used in biomedical research. This study describes the embryonic and fetal development of the domestic cat's central nervous system from 15 days after conception until birth. In total, fifty-seven samples of embryos and fetuses were carefully dissected and analyzed microscopically.

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Background: Aspartame is an artificial sweetener used in foods and beverages worldwide. However, it is linked to oxidative stress, inflammation, and liver damage through mechanisms that are not fully elucidated yet. This work aimed to investigate the effects of long-term administration of aspartame on the oxidative and inflammatory mechanisms associated with liver fibrosis progression in mice.

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Blueberry is a polyphenol-rich fruit bearing great bioactive potential. Natural deep eutectic solvents (NADES) emerged as putatively biocompatible solvents that could substitute for toxic organic solvents in the extraction of fruit phenolic compounds for developing nutraceuticals or functional foods. Therefore, the aim of this study was to investigate the gastroprotective effects and the biocompatibility of a blueberry crude extract (CE) obtained using NADES and of the extract fractions (anthocyanin-rich fraction - ARF; non-anthocyanin phenolic fraction - NAPF) in a model of ethanol-induced gastric ulcer in rats.

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Common opossums (Didelphis marsupialis) are found throughout the Caribbean island of Trinidad and Tobago. The present work was conducted on the fresh normal skin of 10 common opossums and aimed to provide morphometric data and a histological description of the skin in different regions of the body. In the examined regions, the skin presented a typical thin skin morphology, with numerous folds on the surface.

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Flavobacterium columnare, the causative agent of columnaris disease, is a serious bacterial disease responsible for causing devastating mortality rates in several species of freshwater fish, leading to severe economic losses in the aquaculture industry. Notwithstanding the enormous impacts this disease can have, very little is known regarding the interaction between the host and bacterium in terms of the mortality rate of silver catfish (Rhamdia quelen), as well its linkage to gill energetic homeostasis. Therefore, we conducted independent experiments to evaluate the mortality rates caused by F.

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Extracellular adenosine triphosphate (ATP) is as key mediator of immune and inflammatory responses. ATP is normally sequestered in the intracellular milieu and released by apoptotic and necrotic cells, where it acts as a pro-inflammatory mediator in the extracellular milieu. A limited number of studies have explored the involvement of purinergic signaling in oomycete infections, including Saprolegnia parasitica; this is a most destructive oomycete pathogen, associated with high mortality and severe economic losses for fish producers.

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Bacterial diseases are one of the major problems in freshwater fish culture and have been linked to significant losses and high mortality rate. In this study, Nile tilapia Oreochromis niloticus was infected by Providencia rettgeri to evaluate the oxidative stress and antioxidant responses in the fish tissues. Juvenile Nile tilapia was divided into two groups, as follow: control (uninfected) and experimentally infected with 100 μL of P.

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Citrobacter freundii is a fish pathogen known for its ability to cause injury and high mortality. There have been no studies reporting the effect of this bacterium on hematological parameters and internal organ histology in silver catfish (Rhamdia quelen). Therefore, the aim of this study is to evaluate the hematological and histopathological effects of an experimentally induced C.

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Ethnopharmacological Relevance: Verbena litoralis Kunth is a native species of South America, popularly known as gervãozinho-do-campo or erva-de-pai-caetano. It is used in gastrointestinal disorders, as detoxifying the organism, antifebrile properties and amidaglitis.

Aim Of The Study: To identify the chemical constituents of the hydroethanolic extract obtained from the aerial parts of V.

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It is known that the cytotoxic effects of aflatoxin B (AFB) in endothelial cells of the blood-brain barrier (BBB) are associated with behavioral dysfunction. However, the effects of a diet contaminated with AFB on the behavior of silver catfish remain unknown. Thus, the aim of this study was to evaluate whether an AFB-contaminated diet (1177 ppb kg feed) impaired silver catfish behavior, as well as whether disruption of the BBB and alteration of neurotransmitters in brain synaptosomes are involved.

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The precise coupling of spatially separated intracellular adenosine triphosphate (ATP)-producing and ATP-consuming, catalyzed by creatine kinase (CK), adenylate kinase (AK), and pyruvate kinase (PK), is a critical process in the bioenergetics of tissues with high energy demand, such as the branchial tissue. The effects of Citrobacter freundii infection on gills remain poorly understood, limited only to histopathological studies. Thus, the aim of this study was to evaluate whether experimental infection by C.

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Appropriate control of the immune response is a critical determinant of fish health, and the purinergic cascade has an important role in the immune and inflammatory responses. This cascade regulates the levels of adenosine triphosphate (ATP), adenosine diphosphate, adenosine monophosphate and adenosine (Ado), molecules involved in physiological or pathological events as inflammatory and anti-inflammatory mediators. Thus, the aim of this study was to evaluate whether purinergic signaling, through the activities of nucleoside triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase, and adenosine deaminase (ADA), is capable of modulating the cerebral immune and inflammatory responses in silver catfish that is experimentally infected with Streptococcus agalactiae.

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It is becoming evident that bacterial infectious diseases affect brain energy metabolism, where alterations of enzymatic complexes of the mitochondrial respiratory chain and creatine kinase (CK) lead to an impairment of cerebral bioenergetics which contribute to disease pathogenesis in the central nervous system (CNS). Based on this evidence, the aim of this study was to evaluate whether alterations in the activity of complex IV of the respiratory chain and CK contribute to impairment of cerebral bioenergetics during Streptococcus agalactiae infection in silver catfish (Rhamdia quelen). The activity of complex IV of the respiratory chain in brain increased, while the CK activity decreased in infected animals compared to uninfected animals.

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Xanthine oxidase (XO) is a final enzyme of purine metabolism linked with initiation and progression of infectious diseases, since is considered an important source of reactive oxygen species (ROS) and nitric oxide (NO), developing a pro-oxidant and pro-inflammatory profile in some infectious diseases. Thus, the aim of this study was to evaluate the involvement of XO activity in the renal oxidative and inflammatory damage, as well as the interplay with ROS and metabolites of nitric oxide (NOx) levels in silver catfish experimentally infected with Streptococcus agalactiae. Xanthine oxidase activity, and uric acid, ROS and NOx levels increased in renal tissue of infected animals compared to uninfected animals.

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Cytosolic and mitochondrial creatine kinases (CK), through the creatine kinase-phosphocreatine (CK/PCr) system, provide a temporal and spatial energy buffer to maintain cellular energy homeostasis. However, the effects of bacterial infections on the kidney remain poorly understood and are limited only to histopathological analyses. Thus, the aim of this study was to investigate the involvement of cytosolic and mitochondrial CK activities in renal energetic homeostasis in silver catfish experimentally infected with Aeromonas caviae.

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It has long been recognized that there are several infectious diseases linked to the impairment of enzymatic complexes of the mitochondrial respiratory chain, with consequent production of reactive oxygen species (ROS), that contribute to disease pathogenesis. In this study, we determined whether the inhibition on mitochondrial respiratory chain might be considered a pathway involved in the production of ROS in gills of Rhamdia quelen experimentally infected by P. aeruginosa.

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Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for gills bioenergetics, since this tissue plays an important role in the respiratory energy metabolism. The effects of bacterial infection on gills remain poorly understood, limited only to histopathological analyses. Thus, the aim of this study was to investigate whether experimental infection by Pseudomonas aeruginosa strain PA01 alters the enzymes of the phosphoryltransfer network (adenylate kinase (AK), pyruvate kinase (PK) and cytosolic and mitochondrial creatine kinase (CK)) in gills of silver catfish (Rhamdia quelen).

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No-caloric sweeteners, such as aspartame, are widely used in various food and beverages to prevent the increasing rates of obesity and diabetes mellitus, acting as tools in helping control caloric intake. Aspartame is metabolized to phenylalanine, aspartic acid, and methanol. Our aim was to study the effect of chronic administration of aspartame on glutathione redox status and on the trans-sulphuration pathway in mouse liver.

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The aim of this study was to investigate the effect of nerolidol-loaded nanospheres (N-NS) on the treatment of memory impairment caused by Trypanosoma evansi in mice, as well as oxidative stress, and Na, K-ATPase and acetylcholinesterase (AChE) activities in brain tissue. Animals were submitted to behavioral tasks (inhibitory avoidance task and open-field test) 4 days postinfection (PI). Reactive oxygen species (ROS) and thiobarbituric acid-reactive substance (TBARS) levels and catalase (CAT), superoxide dismutase (SOD), Na, K-ATPase and AChE activities were measured on the fifth-day PI.

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The aim of this study was to evaluate the effect of nerolidol free (N-F) and nerolidol-loaded in nanospheres (N-NS) on the hepatic antioxidant/oxidant status of mice experimentally infected by Trypanosoma evansi. In the liver it was measured: reactive oxygen species (ROS), thiobarbituric reactive acid substances (TBARS) and non-protein thiols (NPSH), catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) and performed histopathological examination. In addition, seric levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured.

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