Publications by authors named "Janaina Esmeraldo Rocha"

Bacterial resistance has become a global concern for public health agencies. Various resistance mechanisms found in Staphylococcus aureus strains grant this bacterium resistance to a wide range of antibiotics, contributing to the rise in human mortality worldwide. Resistance mediated by efflux pumps is one of the most prevalent mechanisms in multi-resistant bacteria, which has aroused the interest of several researchers in the search for possible efflux pump inhibitors.

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The occurrence of bacterial resistance has been increasing, compromising the treatment of various infections. The high virulence of Staphylococcus aureus allows for the maintenance of the infectious process, causing many deaths and hospitalizations. The MepA and NorA efflux pumps are transporter proteins responsible for expelling antimicrobial agents such as fluoroquinolones from the bacterial cell.

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The efflux pump mechanism contributes to the antibiotic resistance of widely distributed strains of Staphylococcus aureus. Therefore, in the present work, the ability of the riparins N-(4-methoxyphenethyl)benzamide (I), 2-hydroxy-N-[2-(4-methoxyphenyl)ethyl]benzamide (II), 2, 6-dihydroxy-N-[ 2-(4-methoxyphenyl)ethyl]benzamide (III), and 3,4,5-trimethoxy-N-[2-(4-methoxyphenethyl)benzamide (IV) as potential inhibitors of the MepA efflux pump in S. aureus K2068 (fluoroquinolone-resistant).

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The discovery of antibiotics has significantly transformed the outcomes of bacterial infections in the last decades. However, the development of antibiotic resistance mechanisms has allowed an increasing number of bacterial strains to overcome the action of antibiotics, decreasing their effectiveness against infections they were developed to treat. This study aimed to evaluate the antibacterial activity of synthetic coumarins Staphylococcus aureus in vitro and analyze their interaction with the MepA efflux pump in silico.

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Chalcones have an open chain flavonoid structure that can be obtained from natural sources or by synthesis and are widely distributed in fruits, vegetables, and tea. They have a simple and easy to handle structure due to the α-β-unsaturated bridge responsible for most biological activities. The facility to synthesize chalcones combined with its efficient in combating serious bacterial infections make these compounds important agents in the fight against microorganisms.

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(1) Background: estragole is a monoterpene found in the essential oils of several aromatic plants, which can be used for several pharmacological activities. The aim of this study was to evaluate the antinociceptive effect of estragole (Es) and its -cyclodextrins inclusion complex (Es/β-CD). (2) Methods: the effects of Es and Es/β-CD on the central nervous system (CNS) were evaluated through open field and rota-rod assays, and the antinociceptive effect in formalin models, abdominal writhing induced by acetic acid, hot plate, tail flick test and plantar mechanical hyperalgesia.

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Eugenol has already had its pharmacological properties elucidated in previous studies, including antibacterial and antifungal properties. Based on such information, this study aimed to evaluate the antibacterial and modulatory activity of coumarin compounds prepared from dihydroeugenol and to associate them with blue LED light for the same activity. For this study, five of the substances available: compound 1 (C1), 8-methoxy-2-oxo-6-propyl-2H-chromen-3-carboxylic acid, compound (C2), 3-(hydroxy(4-nitrophenyl)methyl)-8- methoxy-6-propyl-2H-chromen-2-one, compound 7 (C3), 8-hydroxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one, compound 8 (C4), 3-(4-aminobenzoyl)-8-methoxy-6-propyl-2H-chromen-2-one and Compound 9 (C5), 8-methoxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one 2-one.

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The problem of antibiotic resistance by bacteria threatens human health. Therefore, studies in this area seek alternatives to circumvent it. The study with coumarins and eugenol has already proven that these classes of compounds act against bacteria.

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The present study reports the synthesis, characterization, and antibacterial properties of silver trimolybdate (AgMoO.2HO) nanorods. The synthesis was performed using a conventional hydrothermal method.

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A large number of infections are caused by multi-resistant bacteria worldwide, increasing to around 700,000 deaths per year. Because of that, many strategies are being developed to combat the resistance of microorganisms to drugs, and recently, chalcones have been studied for this purpose. Chalcones are known as α, β-unsaturated ketones, characterized by having the presence of two aromatic rings that are joined by a three-carbon chain.

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In recent years, bacterial resistance to traditional drugs has increased, and the need to find new effective antibiotics to treat infections caused by multidrug-resistant bacteria has consequently become more important. The current study aimed to evaluate the potentiation of antibiotic activity and efflux pumps inhibition by (2E)-1-(4-aminophenyl)-3-(4-fluorophenyl)prop-2-en-1-one (PA-Fluorine) against the standard and resistant bacterial strains of Staphylococcus aureus and Escherichia coli. The association between PA-Fluorine and ampicillin reduced the minimum inhibitory concentration (MIC), showing a synergistic effect against S.

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Background: Bacterial resistance to multiple drugs has recently emerged as a serious health problem. Concomitantly, the characterization of new substances with potential antimicrobial activity has been less frequent in the drug development industry. The overexpression of genes encoding efflux pumps that expel antimicrobial drugs from the intracellular environment, lowering these to subinhibitory concentrations, are among the resistance mechanisms predisposing microorganisms to high drug resistance.

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is used in the folk medicine for the treatment of diarrhea and dysentery, indicating that extracts obtained from this species may present pharmacological activities against pathogenic microorganisms. The purpose of this work was to investigate the chemical composition and evaluate the antimicrobial activity of extracts obtained from the leaves (aqueous) and bark (hydroethanolic) of both as single treatments and in combination with conventional drugs. Following a qualitative chemical prospection, the extracts were analyzed by HPLC-DAD.

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The Staphylococcus aureus bacteria is a Gram-positive, immobile, non-spore bacterium, with catalase and positive coagulase, among other characteristics. It is responsible for important infections caused in the population and for hospital infections. Because of that many strategies are being developed to combat the resistance of microorganisms to drugs, in recent times, chalcones have been studied for this purpose.

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: Pathogenic microorganisms are causing increasing cases of mortality and morbidity, along with alarming rates of ineffectiveness as a result of acquired antimicrobial resistance. BiWO showed good potential to be used as an antibacterial substance when exposed to visible light. This study demonstrates for the first time the dimension-dependent antibacterial activity of layered BiWO nanosheets.

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Sexually transmitted diseases (STDs) are produced by pathogens like bacteria, fungi, parasites, and viruses, and may generate severe health problems such as cancer, ulcers, and even problems in the newborn. This narrative review aims to present updated information about the use of natural bioactive compounds for the prevention and treatment of sexually transmitted infections. A search of the literature was performed using databases and search engines such as PubMed, Scopus, Google Scholar and Science Direct.

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Bacterial resistance is a natural process carried out by bacteria, which has been considered a public health problem in recent decades. This process can be triggered through the efflux mechanism, which has been extensively studied, mainly related to the use of natural products to inhibit this mechanism. To carry out the present study, the minimum inhibitory concentration (MIC) tests of the compound limonene were performed, through the microdilution methodology in sterile 96-well plates.

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A large number of infections are caused by multi-resistant bacteria worldwide, adding up to a figure of around 700,000 deaths per year. Because of that many strategies are being developed in order to combat the resistance of microorganisms to drugs, in recent times, chalcones have been studied for this purpose. Chalcones are known as α, β-unsaturated ketones, characterized by having the presence of two aromatic rings that are joined by a three-carbon chain, they are a class of compounds considered an exceptional model due to chemical simplicity and a wide variety of biological activities, which include anticancer, anti-inflammatory, antioxidants, antimicrobials, anti-tuberculosis, anti-HIV, antimalarial, anti-allergic, antifungal, antibacterial, and antileishmanial.

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The antibacterial activity of the monoterpene estragole was evaluated against two strains of bacteria with an efflux pump mechanism, which are Staphylococcus aureus 1199B and S. aureus K2068, which have a NorA and MepA pump, respectively. For that, the methodology proposed by CLSI with modifications was followed, and to evaluate the reversal of the efflux pump, subinhibitory concentrations (MIC/8) of estragole and standard pump inhibitors, CCCP and Chlorpromazine were used and it was verified whether they managed to modulate the action of Norfloxacin, Ciprofloxacin and Ethidium Bromide, an indicator of an efflux pump.

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Astragalus L. is widely distributed throughout the temperate regions of Europe, Asia, and North America. The genus is widely used in folk medicine and in dietary supplements, as well as in cosmetics, teas, coffee, vegetable gums, and as forage for animals.

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Candida infections represent a threat to human health. Candida albicans is the main causative agent of invasive candidiasis, especially in immunosuppressed patients. The emergence of resistant strains has required the development of new therapeutic strategies.

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Efflux pumps and β-lactamases are mechanisms of bacterial resistance that exist in Staphylococcus aureus, where both mechanisms are expressed simultaneously in the SA K4100 strain, with its efflux pump being characterized as QacC (Quaternary Ammonium Compounds C). The search for inhibitors of these mechanisms has grown gradually, with research on isolated compounds, including terpenes, which have innumerable biological activities, being common. This study sought to evaluate the antibacterial activity of Terpinolene against the S.

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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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Essential oils are secondary metabolites with immense pharmacological potential.These substances are abundantly produced by plants of the family Asteraceae, such as Baccharis coridifolia. Previous studies have demonstrated that this species has pharmacological properties that make it a promising source of new antibacterial agents.

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