Publications by authors named "Vera Lucia Dias Siqueira"

Article Synopsis
  • Tuberculous meningitis (TBM) is a severe form of tuberculosis, and a review of studies was conducted to understand its impact on adults in high TB incidence countries.
  • Out of 11,855 articles searched, 21 were reviewed, and 15 included in the meta-analysis, revealing a 25% overall mortality rate and a staggering 70% death rate in Africa.
  • The study found inconsistencies in diagnostic methods and treatment approaches, indicating a pressing need for standardized guidelines to improve diagnosis and treatment to lower mortality rates, especially in African regions.
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  • Polymyxin B (PMB) is currently one of the few options to treat serious infections caused by drug-resistant Gram-negative bacteria, but resistance to PMB is emerging.
  • This study tests several chemical compounds, including 3,5-dinitrobenzoic acid derivatives and isoniazid-acylhydrazones, to see if they can enhance the effectiveness of PMB against resistant bacteria.
  • Results showed that DNH derivatives significantly improved PMB's activity against 80% of tested strains, allowing for effective treatment at much lower concentrations than PMB alone, suggesting they could be valuable in fighting resistant infections.
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  • This study focused on synthesizing 22 salicylhydrazone derivatives to test their effectiveness as new anti-TB drugs in vitro.
  • Three compounds (10, 11, and 18) were highlighted for their promising results, with compound 18 showcasing the best activity against Mycobacterium tuberculosis at a low MIC of 0.49 μg/mL and good safety profile.
  • The compounds exhibited cooperative effects when tested with existing TB drugs and showed potential against both drug-susceptible and resistant strains, particularly compound 18 which stood out due to its low cytotoxicity.
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To review , , and studies examining the antibacterial and immunomodulatory properties of piperine (PPN). This systematic review followed PRISMA guidelines, and five databases were searched. A total of 40 articles were included in this study.

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Tuberculosis (TB), a disease caused by Mycobacterium tuberculosis complex, still presents significant numbers of incidence and mortality, in addition to several cases of drug resistance. Resistance, especially to isoniazid, which is one of the main drugs used in the treatment, has increased. In this context, N-acylhydrazones derived from isoniazid have shown important anti-Mycobacterium tuberculosis activity.

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Due to the significant shortage of therapeutic options for carbapenem-resistant (CRE) infections, new drugs or therapeutic combinations are urgently required. We show in this study that (-)-camphene-based thiosemicarbazide (TSC) may act synergistically with polymyxin B (PMB) against CRE, rescuing the activity of this antimicrobial. With the specific aim of a better molecular understanding of this effect caused by the presence of TSC, theoretical calculations were also performed in this study.

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Piperine (PPN) is a known inhibitor of efflux pumps in and synergism with rifampicin (RIF) has been proven. The current study evaluates the activity of PPN and synergism with RIF in rapidly and slowly growing nontuberculous mycobacteria (NTM). Also, to propose a possible mechanism of interaction of PPN with (Mlp) RNA polymerase (RNAp).

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Article Synopsis
  • * Key insights from the review highlighted five areas of disulfiram's antibacterial activity, including its spectrum of action, potential for drug combinations, and effects on specific bacterial targets, showing promise as a non-antibiotic treatment amid increasing drug resistance.
  • * Despite limited evidence, the study suggests further exploration of disulfiram's use in combination with existing or new antibiotics, particularly for mycobacterial diseases, and its unique mechanism involving copper in Gram-positive bacteria may provide new avenues for drug development.
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Pyrazinamide (PZA) represents a milestone as a first-line antituberculosis drug due to its sterilizing activity against . The protein changes induced by subinhibitory PZA exposure of in acidic pH were evaluated by a proteomic approach. Among the 1059 proteins identified, the specific acidification in the culture medium induced the over-representation of MurF (Rv2157c), and its under-representation was induced by 12 h of PZA exposure.

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  • - The text discusses the serious risks of Group B Streptococcus (GBS) infection in newborns during childbirth, highlighting its potential to lead to death.
  • - A new detection method for GBS from vaginal swabs in pregnant women is outlined, utilizing real-time polymerase chain reaction (qPCR) without the need for prior enrichment.
  • - The qPCR method shows better performance compared to traditional culture methods for detecting GBS.
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Tuberculosis is a disease caused by , with high mortality rates and an extended treatment that causes severe adverse effects, besides the emergence of resistant bacteria. Therefore, the search for new compounds with anti- activity has considerably increased in recent years. In this context, benzohydrazones are significant compounds that have antifungal and antibacterial action.

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The treatment of multidrug-resistant tuberculosis (MDR-TB) is a challenge to be overcome. The increase of resistant isolates associated with serious side effects during therapy leads to the search for substances that have anti-TB activity, which make treatment less toxic, and also act in the macrophage acidic environment promoted by the infection. The aim of this study was to investigate lapachol and β-lapachone activities in combination with other drugs against at neutral and acidic pH and its cytotoxicity.

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Rifampicin plays an important role during the treatment of tuberculosis, which makes it to be recommended throughout the regimen. The molecular target for rifampicin activity and resistance is the bacterial RNA polymerase coded by rpoB. However, it has been observed that Mycobacterium tuberculosis could use different metabolic pathways contributing to drug activity/resistance.

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Minimum bactericidal concentration (MBC) assay is an accepted parameter for evaluating new antimicrobial agents, and it is frequently used as a research tool to provide a prediction of bacterial eradication. To the best of our knowledge, there is no standardization among researchers regarding the technique used to detect a drug's MBC in . Thus, the aim of this systematic review is to discuss the available literature in determining a drug's MBC in , to find the most commonly used technique and standardize the process.

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A series of methyl β-carboline carboxylates (2a-g) and of imide-β-carboline derivatives containing the phthalimide (4a-g), maleimide (5b, g) and succinimide (6b, e, g) moiety were synthesized, and evaluated for their activity against Mycobacterium tuberculosis HRv. The most active β-carboline derivatives against the reference strain were assayed for their cytotoxicity and the activity against resistant M. tuberculosis clinical isolates.

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Background: For more than 60 years, the lack of new anti-tuberculosis drugs and the increase of resistant Mycobacterium tuberculosis lineages exhibit a therapeutic challenge, demanding new options for the treatment of resistant tuberculosis.

Objective: Herein, we determined the (i) activities of (-)-camphene and its derivatives and (ii) combinatory effect with pyrazinamide (PZA) against Mycobacterium tuberculosis in acidic pH and (iii) cytotoxicity on VERO cells.

Methods: The activity of (-)-camphene and its 15 derivatives was determined in M.

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The activity of rifampin (RIF) and piperine was evaluated at the relative transcript levels of 12 efflux pumps (EPs), and an additional mechanism was proposed to be behind the synergic interactions of piperine plus RIF in AutoDock v4.2.3 and Molegro v6 programs were used to evaluate PIP binding in RNA polymerase (RNAP).

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Ethnopharmacological Relevance: Zingiber officinale (ginger) is a perennial herbaceous plant native in tropical Asia and generally cultivated in most American tropical countries with widespread use in popular medicine. Ginger essential oil (GEO) has been reported to exhibit several biological activities, such as antimicrobial.

Aims Of The Study: The aim of this study was to determine the composition and the property of GEO and related fractions against Mtb and NTM, as well as their cytotoxicity.

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Background: The global resurgence of tuberculosis (TB) and the development of drug resistance, as multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mycobacterium tuberculosis isolates, are a threat to TB control and have created a need for new and more effective anti-TB drugs.

Aim: The current study evaluated the in vitro cytotoxicity and activity of Tetradenia riparia essential oil (TrEO) and 6,7-dehydroroyleanone pure compound against M. tuberculosis HRv and susceptible and resistant clinical isolates.

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Article Synopsis
  • Piperine, derived from Piper nigrum and Piper longum, has potential as an efflux pump inhibitor and a complementary treatment for tuberculosis (TB).
  • The systematic review analyzed studies on piperine's effects against mycobacteria, focusing on its mechanisms, drug interactions, and antimycobacterial properties.
  • Out of 225 articles identified, eight met the inclusion criteria and indicated that piperine exhibits effective anti-TB activity, particularly when used alongside other antimicrobials.
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Setting: The increase of multidrug and extensively drug resistant Mycobacterium tuberculosis strains turns the search for new tuberculosis (TB) treatment options of paramount importance.

Objective: In this sense, the present study evaluates the in vitro activity of isoniazid (INH)/rifampicin (RIF)/levofloxacin (LVX) and INH/RIF/linezolid (LNZ) combinations in resistant M. tuberculosis.

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  • The Brazil/Paraguay/Argentina border shows high TB rates and migration, prompting a detailed study using genetic markers to examine Mycobacterium tuberculosis transmission and drug resistance.
  • 97 TB isolates from patients between 2013-2015 were analyzed, revealing significant genetic diversity among the strains linked to clonal variability in this region.
  • The study found that RD lineage accounted for 15.46% of TB cases, with specific MIRU types identified, but no clear link between RD lineage and drug resistance, highlighting the need for further research on MDR-TB risks.
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Objectives: Since resistance of Mycobacterium tuberculosis (Mtb) partially derives from efflux pumps (EPs) in the plasma membrane, the current study evaluates EPs in Mtb exposed to rifampicin in the presence of the EP inhibitor verapamil, within a macrophage environment.

Methods: Human acute monocytic leukaemia cell line THP-1 was infected with Mtb H37Rv and exposed to rifampicin and verapamil alone and in combination for 24 and 72 h. After RNA extraction, quantitative PCR was carried out for 11 EP genes using SYBR green PCR master mix in the StepOne™ Real-Time PCR System.

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  • Health professionals must interview tuberculosis (TB) patients to find and evaluate their close contacts, as close interactions can spread the disease; however, this also requires disclosing the patient’s health status to others.
  • The study analyzed data from over 9,800 TB cases in Paraná, Brazil, between 2008 and 2012, revealing that 29% of adult cases didn’t have their contacts examined, leading to lower treatment success in these cases.
  • Identifying TB contacts is vital for effective disease control and improving treatment outcomes, as involving family members significantly boosts adherence to treatment and the likelihood of curing the disease.
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