Maria Ester Pereira

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Sialic acids and sialidases play important roles in cellular interactions and modulate the recognition of pathogenic microbes by mammalian host cells. Protozoan parasites of the genus Trypanosoma express a unique sialic acid-metabolizing enzyme. This enzyme, named trans-sialidase (TS), catalyzes the transfer of sialic acids from host glycoconjugates to(More)
The effects of CdCl2 and ZnCl2 pretreatments on the inhibition of delta-ALA-D (delta-aminolevulinic acid dehydratase) activity and Hg contents in liver and kidneys of suckling rats intoxicated with HgCl2 were investigated. Zn-pretreatment prevented the effects of mercury at a higher magnitude than CdCl2. Hepatic and renal delta-ALA-D activities were(More)
Alzheimer's disease (AD) is a neurodegenerative disease characterized by cognitive impairment, associated with a reduced concentration of acetylcholine (ACh) in brain cortex and hippocampus. Recently we reported that the N-acetylcysteine (NAC) decreases brain acetylcholinesterase (AChE) activity in vitro. Thus, the aim of the current study was to(More)
The aim of this study was to evaluate cholinesterase activity during the early acute phase of Trypanosoma evansi infection in rats. Fifteen male Wistar rats were randomly distributed into three groups (n=5 animals per group): two trypanosome-infected groups (T3 and T5) and uninfected controls (C). The animals were inoculated intraperitoneally with 10(6)(More)
This paper shows the toxicity of mercury (HgCl(2) 5mg/kg/day for 5 days, sc) applied at specific stages of development (1-5, 8-12 or 17-21 days old, 1st, 2nd and 3rd phases, respectively) on the performance of rats in three behavioral tasks and on cerebral mercury levels. The mercury exposure at the 1st and 2nd phases affected the performances of rats in(More)
This study evaluated the effects of HgCl2 on renal parameters in nonlactating and lactating rats and their pups, as well as the preventive role of ZnCl2 . Rats received 27 mg kg(-1) ZnCl2 for five consecutive days and 5 mg kg(-1) HgCl2 for five subsequent days (s.c.). A decrease in δ-aminolevulinic acid dehydratase (δ-ALA-D) activity in the blood and an(More)
Ebselen is a seleno compound whose antioxidant properties have been attributed to its thiol-peroxidase and thioredoxin-like activity. However, the excessive oxidation of thiols can be potentially toxic. Thus, this work investigated whether lactate dehydrogenase (LDH) can be a possible in vitro target to the toxicity of ebselen, in comparison with diphenyl(More)
Oximes are a class of compounds normally used to reverse the acetylcholinesterase (AChE) inhibition caused by organophosphates (OPs). Conversely, researches focusing on the possible antioxidant properties of these compounds are lacking in the literature. The aim of this study was to investigate the potential antioxidant and toxic properties of(More)
ETHNOPHARMACOLOGICAL RELEVANCE The infusion or decoction of Mirabilis jalapa leaves is used in traditional medicine in Brazil to treat inflammatory and painful diseases. AIM OF THE STUDY The present study examined the antinociceptive effect of Mirabilis jalapa extracts from leaves and stems in models of pain in mice. MATERIALS, METHODS AND RESULTS The(More)
Oximes are compounds generally used to reverse the acetylcholinesterase (AChE) inhibition caused by organophosphates (OPs). The aim of this study was to examine the capacity of the butane-2,3-dionethiosemicarbazone oxime to scavenge different forms of reactive species (RS) in vitro, as well as counteract their formation. The potential antioxidant and toxic(More)