Publications by authors named "Teresinha Goncalves Silva"

New leishmanicidal products are needed for the treatment to be effective, since current drugs are toxic to healthy human/animal cells and have low efficacy against the parasite. Bioactive compounds from microalgae, such as lectins, can be explored as new anti-Leishmania candidates. This study aimed to evaluate the cytotoxic and anti-Leishmania action of the cell extract (CE) and lectin (CVU) from Chlorella vulgaris biomass.

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The efflux systems are considered important mechanisms of bacterial resistance due to their ability to extrude various antibiotics. Several naturally occurring compounds, such as sesquiterpenes, have demonstrated antibacterial activity and the ability to inhibit efflux pumps in resistant strains. Therefore, the objective of this research was to analyze the antibacterial and inhibitory activity of the efflux systems NorA, Tet(K), MsrA, and MepA by sesquiterpenes nerolidol, farnesol, and α-bisabolol, used either individually or in liposomal nanoformulation, against multi-resistant strains.

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Valencene and nootkatone are aromatic sesquiterpenes with known biological activities, such as antimicrobial, antioxidant, anti-inflammatory, and antitumor. Given the evidence that encapsulation into nanosystems, such as liposomes, could improve the properties of several compounds, the present study aimed to evaluate the activity of these sesquiterpenes in their isolated state or in liposomal formulations against strains of carrying efflux pumps. The broth microdilution method evaluated the antibiotic-enhancing activity associated with antibiotics and ethidium bromide (EtBr).

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The -acylhydrazone function has been reported as a pharmacophore group of molecules with diverse pharmacological activities, including anti-inflammatory effects. Therefore, this study was designed to evaluate the anti-inflammatory potential of the compound '-(3-(1H-indol-3-yl)benzylidene)-2-cyanoacetohydrazide (JR19) in vivo. The study started with the carrageenan-induced peritonitis model, followed by an investigation of leukocyte migration using the subcutaneous air pouch test and an assessment of the antinociceptive profile using formalin-induced pain.

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The present study proposed the synthesis of a novel acridine derivative not yet described in the literature, chemical characterization by NMR, MS, and IR, followed by investigations of its antileishmanial potential. In vitro assays were performed to assess its antileishmanial activity against strains and cytotoxicity against macrophages through MTT assay and annexin V-FITC/PI, and the ability to perform an immunomodulatory action using CBA. To investigate possible molecular targets, its interaction with DNA in vitro and in silico targets were evaluated.

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Antibiotic resistance can be characterized, in biochemical terms, as an antibiotic's inability to reach its bacterial target at a concentration that was previously effective. Microbial resistance to different agents can be intrinsic or acquired. Intrinsic resistance occurs due to inherent functional or structural characteristics of the bacteria, such as antibiotic-inactivating enzymes, nonspecific efflux pumps, and permeability barriers.

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β-lapachone is a 1,2-naphthoquinone of great therapeutic interest that induces cell death by autophagy and apoptosis in tumor cells due to oxidative stress increasing. However, its high toxicity in healthy tissues limits its clinical use, which stimulates the planning and synthesis of more selective analogs. The aim of this study was to investigate the cytotoxic activity of three thiosemicarbazones derived from β-lapachone (BV2, BV3 and BV5) in leukemia cells.

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Background: Chronic lung diseases are characterized by airway inflammation and remodelling of the lung parenchyma that triggers considerable impairment of respiratory function.

Objective: In this study, two compounds belonging to the N-acylhydrazone class were evaluated, aiming to identify new therapeutic agents for pulmonary inflammatory diseases.

Materials And Methods: The acute toxicity of 2-cyano-N'-(3-ethoxy-4-hydroxybenzylidene)- acetohydrazide (JR-12) and N'-benzylidene-2-cyano-3-phenylacrylohydrazide (JR09-Bz) was evaluated.

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Ethnopharmacological Relevance: Moringa oleifera Lam. leaves infusion and powder are widely used by population due the nutritional and medicinal potentials, however data regarding safety of use are still inconclusive, leading to prohibition of this plant in some countries.

Aim Of The Study: The present work investigated the nutritional and phytochemical composition, acute and 28-day repeated dose toxicity, and genotoxicity of M.

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Cymbopogon winterianus, known as “citronella grass”, is an important aromatic and medicinal tropical herbaceous plant. The essential oil of C. winterianus (EOCw) is popularly used to play an important role in improving human health due to its potential as a bioactive component.

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Thiosemicarbazones are well known for their broad spectrum of action, including antitumoral and antiparasitic activities. Thiosemicarbazones work as chelating binders, reacting with metal ions. The objective of this work was to investigate the , , and toxicity and oxidative stress of 2-acetylpyridine-(4)-orthochlorophenyl thiosemicarbazone (TSC01).

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Thiazolidine compounds NJ20 {(E)-2-(2-(5-bromo-2-methoxybenzylidene)hydrazinyl)-4-(4-nitrophenyl)thiazole} and NW05 [(2-(benzo (d) (1,3) dioxol-4-ylmethylene)-N-(4-bromophenyl)-thiosemicarbazone] potentiated the effect of norfloxacin in resistant bacteria; however, there are no reports on their effects on in the literature. The objective of this work was to evaluate the behavioral effects and oxidative markers of NW05 and NJ20 in lobster cockroach . To evaluate the behavioral study, a video tracking software was used to evaluate the locomotor points and the exploratory profile of cockroaches in the horizontal and vertical regions of a new environment.

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Background: In a study recently published by our research group, the isoxazoline-acylhydrazone derivatives R-99 and R-123 presented promising antinociceptive activity. However, the mechanism of action of this compound is still unknown.

Objective: This study aimed to assess the mechanisms involved in the antinociceptive activity of these compounds in chemical models of pain.

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Pim kinases (proviral integration site for Moloney murine leukemia virus kinases) are overexpressed in various types of hematological malignancies and solid carcinomas, and promote cell proliferation and survival. Thus, Pim kinases are validated as targets for antitumor therapy. In this context, our combined efforts in natural product-inspired library generation and screening furnished very promising dibenzo[,]furan derivatives derived from cercosporamide.

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The present study describes the use of fucoidan, a negative sulfated polysaccharide, as a coating material for the development of liposomes targeted to macrophages infected with . First, fucoidan was chemically modified to obtain a hydrophobized-fucoidan derivative (cholesteryl-fucoidan) using a two-step microwave-assisted (μW) method. The total reaction time was decreased from 14 hours to 1 hour while maintaining the overall yield.

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This study aimed to evaluate the antibacterial activity and to verify, in silico and in vitro, the inhibition of efflux mechanisms using a series of synthesized 1,8-naphthyridines sulfonamides against Staphylococcus aureus strains carrying MepA efflux pumps. The chemical synthesis occurred through the thermolysis of the Meldrum's acid adduct. The sulfonamide derivatives were obtained by the sulfonylation of 2-amino-5‑chloro-1,8-naphthyridine with commercial benzenesulfonyl chloride.

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Egletes viscosa is a plant with therapeutic value due to its antibacterial, antinociceptive and gastroprotective properties. This study aimed to purify, characterize, and evaluate the cytotoxicity of a lectin (EgviL) from the floral capitula of E. viscosa.

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(1) Background: Infections by species represent a serious threat to the health of immunocompromised individuals. Evidence has indicated that nerolidol has significant antifungal properties. Nonetheless, its use is restricted due to a low water solubility and high photosensitivity.

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plants have received increasing recognition due to its nutritional and biological properties. A number of secondary metabolites are present in its leaves, fruits, and other parts of the plant. Among the diverse plants' bioactive effects, their antioxidant, antimicrobial, and anticancer activities comprise those that have gained more attention.

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Chrysobalanus icaco L. is a native plant of Brazil used as a food source and traditionally for the treatment of various diseases. The aim of study was performed the phytochemical analysis by UPLC-DAD-ESI-QTOF-MS/MS, and evaluated acute and repeated dose oral toxicities of the C.

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The aim of this study was to investigate the anti-inflammatory effects of two new isoxazoline-acylhydrazone derivatives: '-(4-methoxybenzylidene)-6-(4-nitro-benzoyl)-3,5,6,6-tetrahydro-4-pyrrolo[3,2-]isoxazole-3-carbohydrazide (R-123) and '-(4-chlorobenzylidene)-6-(4-chlorobenzoyl)-3,5,6,6-tetrahydro-4-pyrrolo[3,2-]isoxazole-3-carbohydrazide (R-99). An air pouch induced by carrageenan was used for screening the best dose of R-99 and R-123. Using this mouse model, leukocyte migration and cytokine levels (TNF-α and IL-1β) were determined.

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The search for new drugs with anti-inflammatory properties remains a challenge for modern medicine. Among the various strategies for drug discovery, deriving new chemical entities from known bioactive natural and/or synthetic compounds remains a promising approach. Here, we designed and synthesized CVIB, a codrug developed by association of carvacrol (a phenolic monoterpene) with ibuprofen (a non-steroidal anti-inflammatory drug).

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Thiazol and thiazolidinedione derivatives are known in the literature for presenting several biological activities, such as anti-diabetic, anti-inflammatory, antiparasitic, antifungal and antimicrobial activity. With this in mind, this study reports on the synthesis and antibacterial activity of thiazole (NJ) and thiazolidinedione (NW) derivatives, as well as their effects in association with norfloxacin, against NorA efflux pumps in the Staphylococcus aureus 1199B (SA-1199B) strain. Among the 14 compounds evaluated, 9 were found to potentiate norfloxacin activity, with 4 compounds from the NJ series promoting a threefold norfloxacin MIC reduction.

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Background: Considering the need for the development of new antitumor drugs, associated with the great antitumor potential of thiophene and thiosemicarbazonic derivatives, in this work we promote molecular hybridization approach to synthesize new compounds with increased anticancer activity.

Objective: Investigate the antitumor activity and their likely mechanisms of action of a series of N-substituted 2-(5-nitro-thiophene)-thiosemicarbazone derivatives.

Methods: Methods were performed in vitro (cytotoxicity, cell cycle progression, morphological analysis, mitochondrial membrane potential evaluation and topoisomerase assay), spectroscopic (DNA interaction studies), and in silico studies (docking and molecular modelling).

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Objective: Avicennia schaueriana Stapf is an endemic mangrove species widely used by traditional Brazilian communities as a folk remedy for the treatment of rheumatism, ulcers, and skin wounds. The aim of the present study was to evaluate the gastroprotective potential of the ethyl acetate extract from the leaves of A. schaueriana (As-AcOEt).

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