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Abstract The persistent increase of multidrug-resistant (MDR) Mycobacterium tuberculosis (Mtb) infections negatively impacts Tuberculosis treatment outcomes. Host-directed therapies (HDT) pose an complementing strategy, particularly since Mtb is highly successful in evading host-defense by manipulating host-signaling pathways. Here, we screened a library containing autophagy-modulating compounds for their ability to inhibit intracellular Mtb-bacteria. Several active compounds were identified, including two drugs of the diphenylbutylpiperidine-class, Fluspirilene and Pimozide, commonly used as antipsychotics. Both molecules inhibited intracellular Mtb in pro- as well as anti-inflammatory primary human macrophages in a host-directed manner and synergized with conventional anti-bacterials. Importantly, these inhibitory effects extended to MDR-Mtb strains and the unrelated intracellular pathogen, Salmonella enterica serovar Typhimurium (Stm). Mechanistically Fluspirilene and Pimozide were shown to regulate autophagy and alter the lysosomal response, partly correlating with increased bacterial localization to autophago(lyso)somes. Pimozide’s and Fluspirilene’s efficacy was inhibited by antioxidants, suggesting involvement of the oxidative-stress response in Mtb growth control. Furthermore, Fluspirilene and especially Pimozide counteracted Mtb-induced STAT5 phosphorylation, thereby reducing Mtb phagosome-localized CISH that promotes phagosomal acidification. In conclusion, two approved antipsychotic drugs, Pimozide and Fluspirilene, constitute highly promising and rapidly translatable candidates for HDT against Mtb and Stm and act by modulating the autophagic/lysosomal response by multiple mechanisms.

Background: As new and improved antigen-detecting rapid diagnostic tests for SARS-CoV-2 infection (Ag-RDT) continue to be developed, assessing their diagnostic performance is necessary to increase test options with accurate and rapid diagnostic capacity especially in resource-constrained settings. This study aimed to assess the performance of two Ag-RDTs in a population-based study., Methods: We conducted a diagnostic accuracy study in neighborhoods with high socioeconomic vulnerability in Salvador-Brazil, including individuals aged ≥12 years old who attended primary health services, between July and December 2022, with COVID-19 symptoms or who had been in contact with a confirmed case. Two Ag-RDTs were compared in parallel using reverse transcription polymerase chain reaction (RT-PCR) as reference standard, the PanbioTM COVID-19 Ag test (Abbott®) and Immuno-Rapid COVID-19 Ag (WAMA Diagnostic®). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated., Results: For the Abbott test the sensitivity was 52.7% (95% CI: 44.3% - 61.0%), specificity 100% (95% CI: 98.7% - 100%), PPV 100% (95% CI: 95.4% - 100%) and NPV 80.4% (95% CI: 75.9% - 84.4%). For the WAMA test, the sensitivity was 53.4% (95% CI: 45.0% - 61.6%), specificity 100% (95% CI: 98.7% - 100%), PPV 100% (95% CI: 95.4% - 100%) and NPV 80.7% (95% CI: 76.2% - 84.6%). Sensitivity for the group with Cycle Threshold (CT) <24 was 82.3% (95%CI: 72.1-90.0, n = 83) for PanbioTM COVID-19 Ag test and 87.3% (95%CI: 77.9-93.8, n = 83) for Immuno-Rapid COVID-19 Ag test., Conclusion: Sensitivity for both Ag-RDT was lower than reported by manufacturers. In the stratified analysis, sensitivity was higher among those with lower CT values <24. Specificity was high for both rapid antigen tests. Both Ag-RDT showed to be useful for rapid diagnostic of potential cases of COVID-19. Negative results must be assessed carefully according to clinical and epidemiological information., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Zeballos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The global burden of tuberculosis (TB) is aggravated by the continuously increasing emergence of drug resistance, highlighting the need for innovative therapeutic options. The concept of host-directed therapy (HDT) as adjunctive to classical antibacterial therapy with antibiotics represents a novel and promising approach for treating TB. Here, we have focused on repurposing the clinically used anticancer drug tamoxifen, which was identified as a molecule with strong host-directed activity against intracellular Mycobacterium tuberculosis ( Mtb ). Using a primary human macrophage Mtb infection model, we demonstrate the potential of tamoxifen against drug-sensitive as well as drug-resistant Mtb bacteria. The therapeutic effect of tamoxifen was confirmed in an in vivo TB model based on Mycobacterium marinum infection of zebrafish larvae. Tamoxifen had no direct antimicrobial effects at the concentrations used, confirming that tamoxifen acted as an HDT drug. Furthermore, we demonstrate that the antimycobacterial effect of tamoxifen is independent of its well-known target the estrogen receptor (ER) pathway, but instead acts by modulating autophagy, in particular the lysosomal pathway. Through RNA sequencing and microscopic colocalization studies, we show that tamoxifen stimulates lysosomal activation and increases the localization of mycobacteria in lysosomes both in vitro and in vivo , while inhibition of lysosomal activity during tamoxifen treatment partly restores mycobacterial survival. Thus, our work highlights the HDT potential of tamoxifen and proposes it as a repurposed molecule for the treatment of TB. IMPORTANCE Tuberculosis (TB) is the world's most lethal infectious disease caused by a bacterial pathogen, Mycobacterium tuberculosis. This pathogen evades the immune defenses of its host and grows intracellularly in immune cells, particularly inside macrophages. There is an urgent need for novel therapeutic strategies because treatment of TB patients is increasingly complicated by rising antibiotic resistance. In this study, we explored a breast cancer drug, tamoxifen, as a potential anti-TB drug. We show that tamoxifen acts as a so-called host-directed therapeutic, which means that it does not act directly on the bacteria but helps the host macrophages combat the infection more effectively. We confirmed the antimycobacterial effect of tamoxifen in a zebrafish model for TB and showed that it functions by promoting the delivery of mycobacteria to digestive organelles, the lysosomes. These results support the high potential of tamoxifen to be repurposed to fight antibiotic-resistant TB infections by host-directed therapy.

Introduction: This study aimed to evaluate if the apical patency can influence the adaptation of the master cone of gutta-percha, quantifying the volume of voids and areas at the last 2 mm of the working length (WL)., Materials and Methods: Sixty distobuccal canals of extracted upper molars were divided into 3 groups ( n =20) based on the patency length (A: passed 1 mm beyond the apical foramen (AF), B: at the AF and C: 1 mm short of the AF) with the Easy ProDesign Logic 25/0.01 file. Each group was subdivided into 2 subgroups ( n =10) based on the WL established to prepare the root canal (1: 1 mm short of the AF or 2: at the AF) with the Easy ProDesign Logic 25/0.05 file. After the scan, void volumes were calculated from the last 2 mm of the WL and void areas at 0 mm, 1 mm and 2 mm of the last of WL, as well as the relation between the tip and taper of the master cone with the amount of void volume and areas. To investigate statistically significant differences, we used the Kruskal-Wallis statistical test., Results: There were more voids in volume when patency was achieved 1 mm beyond the AF and the root canal preparation was conducted at 1mm short of the AF (A1 group). Furthermore, the same group showed more voids areas, mainly on the last millimeter of WL., Conclusion: Achieving apical patency at 1 mm beyond the AF followed by instrumentation 1 mm short of the AF created more voids between the master gutta-percha cone and the root canal wall, especially on the last millimeter of WL., Competing Interests: ‘None declared’.

Environmental contamination caused by inorganic compounds is a major problem affecting soils and surface water. Most remediation techniques are costly and generally lead to incomplete removal and production of secondary waste. Nanotechnology, in this scenario with the zero-valent iron nanoparticle, represents a new generation of environmental remediation technologies. It is non-toxic, abundant, cheap, easy to produce, and its production process is simple. However, in order to decrease the aggregation tendency, the zero-iron nanoparticle is frequently coated with chemical surfactants synthesized from petrochemical sources, which are persistent or partially biodegradable. Biosurfactants (rhamnolipids), extracellular compounds produced by microorganisms from hydrophilic and hydrophobic substrates can replace synthetic surfactants. This study investigated the efficiency of a rhamnolipid biosurfactant on the aggregation of nanoscale zer-valent iron (nZVI) and its efficiency in reducing nitrate in simulated groundwater at pH 4.0. Two methods were tested: 1) adding the rhamnolipid during chemical synthesis and 2) adding the rhamnolipid after chemical synthesis of nZVI. Scanning electron microscopy field emission, X-ray diffractometry, Fourier transform infrared spectroscopy, thermogravimetric analysis, Dynamic Light Scattering, and zeta potential measurements were used to characterize bare nZVI and rhamnolipid-coated nZVI. The effects of the type of nZVI and initial NO 3 concentration were examined. Nanoscale zer-valent iron with the addition of the rhamnolipid after synthesis achieved the best removal rate of nitrate (about 78%), with an initial nitrate concentration of 25 mg L -1 . The results suggest that nZVI functionalized with rhamnolipids is a promising strategy for the in situ remediations of groundwater contaminated by NO 3 , heavy metal, and inorganic carbon., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Moura, Salazar-Bryam, Piazza, Carvalho dos Santos, Jafelicci, Marques and Contiero.)

In this work, a set of experimental electrophoretic mobility (μ e ) data was used to show how inappropriate selection of the electrokinetic model used to calculate the zeta potential (ζ-potential) can compromise the interpretation of the results for nanoparticles (NPs). The main consequences of using ζ-potential values as criteria to indicate the colloidal stability of NP dispersions are discussed based on DLVO interaction energy predictions. For this, magnetite (Fe 3 O 4 ) NPs were synthesized and characterized as a model system for performing electrokinetic experiments. The results showed that the Fe 3 O 4 NPs formed mass fractal aggregates in solution, so the ζ-potential could not be determined under ideal conditions when μ e depends on the NP radius. In addition, the Dukhin number (Du) estimated from potentiometric titration results indicated that stagnant layer conduction (SLC) could not be neglected for this system. The electrokinetic models that do not consider SLC grossly underestimated the ζ-potential values for the Fe 3 O 4 NPs. The DLVO interaction energy predictions for the colloidal stability of the Fe 3 O 4 NP dispersions also depended on the electrokinetic model used to calculate the ζ-potential. The results obtained for the Fe 3 O 4 NP dispersions also suggested that, contrary to many reports in the literature, high ζ-potential values do not necessarily reflect high colloidal stability for charge-stabilized NP dispersions.

The development of more effective vaccines against Mycobacterium tuberculosis has become a world priority. Previously, we have shown that a recombinant BCG expressing the LTAK63 adjuvant (rBCG-LTAK63) displayed higher protection than BCG against tuberculosis challenge in mice. In order to elucidate the immune effector mechanisms induced by rBCG-LTAK63, we evaluated the immune response before and after challenge. The potential to induce an innate immune response was investigated by intraperitoneal immunization with BCG or rBCG-LTAK63: both displayed increased cellular infiltration in the peritoneum with high numbers of neutrophils at 24 h and macrophages at 7 d. The rBCG-LTAK63-immunized mice displayed increased production of Nitric Oxide at 24 h and Hydrogen Peroxide at 7 d. The number of lymphocytes was higher in the rBCG-LTAK63 group when compared to BCG. Immunophenotyping of lymphocytes showed that rBCG-LTAK63 immunization increased CD4 + and CD8 + T cells. An increased long-term Th1/Th17 cytokine profile was observed 90 d after subcutaneous immunization with rBCG-LTAK63. The evaluation of immune responses at 15 d after challenge showed that rBCG-LTAK63-immunized mice displayed increased TNF-α-secreting CD4 + T cells and multifunctional IL-2 + TNF-α + CD4 + T cells as compared to BCG-immunized mice. Our results suggest that immunization with rBCG-LTAK63 induces enhanced innate and long-term immune responses as compared to BCG. These results can be correlated with the superior protection induced against TB.

Vitamin A is a crucial micronutrient for pregnant women and their fetuses. In addition to being essential for morphological and functional development and for ocular integrity, vitamin A exerts systemic effects on several fetal organs and on the fetal skeleton. Vitamin A requirements during pregnancy are therefore greater. Vitamin A deficiency (VAD) remains the leading cause of preventable blindness in the world. VAD in pregnant women is a public health issue in most developing countries. In contrast, in some developed countries, excessive vitamin A intake during pregnancy can be a concern since, when in excess, this micronutrient may exert teratogenic effects in the first 60 days following conception. Routine prenatal vitamin A supplementation for the prevention of maternal and infant morbidity and mortality is not recommended; however, in regions where VAD is a public health issue, vitamin A supplementation is recommended to prevent night blindness. Given the importance of this topic and the lack of a complete, up-to-date review on vitamin A and pregnancy, an extensive review of the literature was conducted to identify conflicting or incomplete data on the topic as well as any gaps in existing data.

Vitamin A is essential for mother and child; however, vitamin A deficiency (VAD) remains a public health issue in various countries, affecting around 19 million pregnant women. In Brazil, the scarcity and inconsistency of data have prevented the prevalence and epidemiological status of VAD from being established. This study aimed to analyze vitamin A nutritional status in women receiving prenatal care at a reference center in northeastern Brazil. A cross-sectional study was conducted with a sample of 676 women. Serum retinol was measured by high-performance liquid chromatography. Subclinical infection was detected by measuring C-reactive protein (CRP). The World Health Organization criteria were used in the prevalence analysis, VAD classification level, and CRP effect evaluation. The prevalence of VAD (serum retinol <0.70 μmol/L) was 6.2% (95% confidence interval 4.5⁻8.3). In the univariate analysis, the variables significantly associated with VAD ( p < 0.05) were having <12 years of schooling, being in the third trimester of pregnancy, and anemia. In the final multivariate model, the variables that remained significantly associated ( p < 0.05) were being in the third trimester of pregnancy and anemia. VAD constituted a mild public health problem in this sample of pregnant women and was associated with the third trimester of pregnancy and maternal anemia.