Resumo em Inglês:

This review describes the development and translational application of OncoTherad (MRB CFI-1), a novel nanoimmunotherapeutic agent entirely synthesized and validated within a Brazilian public university. Rationally designed through chemical engineering, MRB-CFI-1 is a nanostructured complex formed by the self-assembly of an inorganic phosphate-magnesium scaffold (CFI-1) and a hydrolytic protein (P14-16), resulting in a stable supramolecular complex with strong immunomodulatory activity. Comprehensive physicochemical characterization-including X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering, zeta potential, and both thermogravimetric and calorimetric analyses-confirmed the crystalline architecture, colloidal stability, and structural integrity of the complex under physiological conditions. These features support the targeted activation of Toll-like receptors 4 and 2, driving robust interferon-mediated immune responses. Preclinical studies demonstrated pronounced antitumor activity, immune remodeling, and safety across bladder, colorectal, and ovarian cancer models. Clinically, OncoTherad achieved a 72.7% complete response rate in patients with non-muscle invasive bladder cancer, extending median recurrence-free survival to 21.4 months without severe adverse events. Under Brazil’s compassionate-use regulation, the formulation was also administered to eight patients with recurrent glioblastoma in combination with second-line chemotherapy, resulting in a median overall survival of 18 months-surpassing historical benchmarks-and radiological stability in 87.5% of cases. A representative patient exhibited a 75% reduction in tumor volume alongside marked neurological recovery. Beyond its therapeutic impact, OncoTherad represents a chemically defined, cost-effective innovation pathway, anchored in sovereign intellectual property and coordinated public-sector efforts. This case highlights the potential of academic nanopharmaceutical development to deliver scalable, high-impact oncologic therapies within emerging health systems.

Resumo em Inglês:

Abstract Technologies offering economic, technical, and environmental advantages over conventional chemical products hold promise for replacing chemical pesticides and fertilizers. Due to the positive interactions between plant growth-promoting yeasts (PGPY) and plants, there has been significant focus on developing bioinputs derived from these microorganisms and their metabolites. However, to advance the development of more specific and effective bioinputs, while also ensuring the health of both producers and consumers, it is crucial to deepen our understanding of microorganism-plant interactions, plant responses to microbial presence, and the metabolic changes in plants following bioinput application. Mass spectrometry-based metabolomics offers valuable insights into the metabolite interactions between microorganisms and plants, proving essential for a comprehensive understanding of these processes. This review presents the current state of mass spectrometry-based metabolomics, highlighting targeted and untargeted approaches, sample preparation, instrumentation, and data analysis methods, as well as their application in investigating the benefits of PGPY. The findings aim to provide insights that can aid in the development of commercial bioinputs. Despite substantial research published in scientific journals, only a limited number of yeast-based bioinputs have been commercialized in recent years, underscoring both the challenges and opportunities within this field.

Resumo em Inglês:

This study presents a bibliographic review compiling data on global masks consumption during the coronavirus disease 2019 (COVID-19) pandemic, disposal practices, the release of microplastic and nanoplastic (MNPs) from masks, and their environmental consequences. Global demand for masks increased dramatically compared to pre-pandemic levels, with estimates ranging from 21 billion to 2,555 billion single-use masks per month, underscoring the essential role of personal protective equipment (PPE) in infection control. Asia was identified as the largest consumer and generator of mask waste, followed by the Americas (North and South). This study also demonstrates that disposable masks release MNPs into different environmental matrices, with ultraviolet radiation (UV) and mechanical stress acting as drivers of this process. However, the reviewed studies employed several measurement units, making comparisons challenging hindering direct comparisons, a challenge that highlights the need for standardized methodologies and units. Polypropylene was the predominant constituent of the released particles, as expected due to its widespread use in mask manufacturing. This review also emphasizes the adverse effects of discarded masks on biota and the documented impacts of MNPs released during simulated weathering on model organisms. Overall, there is an urgent need for research focused on standardizing units, improving exposure realism, and strengthening waste-management strategies during health crises. Such efforts are essential to balance infection control with minimizing the environmental burden of single-use plastics and to inform future pandemic preparedness and policy.

Resumo em Inglês:

Myrciaria tenella (DC.) O. Berg is a native and non-endemic fruit tree from Brazil, popularly known as cambuí, and widely used to treat skin rashes, diarrhea, herpes, and colic. The present study aimed to evaluate the influence of climatic parameters on the yield and chemical composition of the essential oil of this species. M. tenella leaves were collected in Salvaterra, in Marajó Island, Pará, Brazil. Essential oils were extracted by hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry. The correlations between yields and climatic parameters were verified using chemometrics tools. M. tenella essential oils showed an average yield of 1.44 ± 0.46% and the highest yield in October (2.6%). There was no significant difference in yield throughout the year. A total of 105 constituents were identified: (E)-caryophyllene (0 to 31%), caryophyllene oxide (0 to 33.61%), δ-cadinene (0 to 6.9%), 1-epi-cubenol (1.96 to 5.82%), and aromadendrene (1.16 to 5.84%) were the major constituents. Temperature, humidity, and insolation significantly influenced the levels of the classes and the main components. Multivariate analysis showed a homogeneous distribution of the samples with high chemical variability. The M. tenella essential oils show variations throughout the year, indicating independence from climatic conditions.

Resumo em Inglês:

This study focused on theoretical investigation of a fluorescent probe formed by conjugating a benzo[e]indolium fluorophore and a 4-(4-methylpiperazin-1-yl) benzene moiety via an ethylene linkage for sulfite detection. The Michael addition of sulfite to the ethylene bond altered the geometric and electronic structures of the probe, disrupting the charge transfer pathway, which was reflected in changes to the UV absorption and fluorescence emission spectra. The probe showed a fast response, low limits of detection, and high precision for sulfite detection, providing a promising technology for food safety and biological analysis. Theoretical calculations in this research, including density of states analysis, UV-Vis absorption, electron density distribution, and reorganization energy calculations, were in good agreement with experimental findings and provide the insights for designing the new functional fluorescent probe.

Resumo em Inglês:

Dissimilatory adenosine 5’-phosphosulfate reductase (APSrAB) is a metalloenzyme of the metabolic pathway of sulfate-reducing microorganisms, which generates H2S in oil production wells, causing losses in the oil industry. A set of 32 compounds derivatives of adenosine 5’-phosphosulfate (APS), previously evaluated as inhibitors of the assimilatory adenosine 5’-phosphosulfate reductase (APSr), were challenged in this current work by in silico molecular docking and molecular dynamics (MD) techniques as potential inhibitors of the APSrAB (APS is substrate of both enzymes). From this set, 20 compounds showed the highest affinity by the APSrAB (tendency to remain in the binding site pointed out by the docking experiments). The residues of the active site (71-398 region) had hydrogen bonds with a lifetime of more than 10.00% (mainly Arg265). They were responsible for the binding of these ligands over time, while the binding energy (ΔGbinding) values showed the energetic contribution of these residues to the stabilization of the APSrAB-ligand complex (mainly Arg265). Thus, compounds 13d, 14a, 14d, 16c, and 16d showed ΔGbinding values more favorable than -30.00 kcal mol-1 and had more affinity for the enzyme than the APS substrate, especially 16d, which can be pointed as an APSrAB potential inhibitor.

Resumo em Inglês:

Essential oils (EOs) present limitations such as volatility, low water solubility, and instability, which restrict their direct application in pharmaceutical and cosmetic formulations. This study aimed to develop and characterize a nanoemulsion (NE) based on Melaleuca alternifolia EO, overcoming these challenges. The EO was extracted by hydrodistillation (yield: 3%) and analyzed by gas chromatography-mass spectrometry (GC-MS), identifying terpinen-4-ol (47.49%), γ-terpinene (17.89%), and α-terpinene (9.35%) as major components. The NE was prepared using ultrasound and Tween 80 as a surfactant, resulting in a monomodal distribution with a mean droplet size of 60 nm, confirmed by dynamic light scattering and the Tyndall effect. Stability assessments, including thermal and centrifugation tests, revealed a robust system, with optimal performance at 5-25 °C and controlled release behavior at 50 °C. The NE demonstrated potent antimicrobial activity, with minimum inhibitory concentrations (MIC) as low as 0.0078 μg mL−1. Although not directly compared to the crude EO, the results indicate preserved and possibly enhanced antimicrobial efficacy due to encapsulation. These findings suggest that the nanoemulsion is a promising platform for pharmacosmetic applications, enabling EO delivery at low concentrations while improving physicochemical stability and biological performance.

Resumo em Inglês:

Hydrogen (H2) fuel has emerged as a clean and sustainable energy source, however, efficient and safe storage of H2 remains challenging. This study synthesized phosphorus-doped hydrochar (HC) from malt bagasse waste (BSG) using hydrothermal process with phosphoric acid (H3PO4) activation in a one-pot reaction, known as wet pyrolysis, under mild synthesis conditions. The HC was then used as a carbon support for cobalt (Co) and nickel (Ni) nanoparticles to catalyze H2 evolution from the solid-state chemical store sodium borohydride (NaBH4). The nanocatalysts were characterized using various techniques, including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis. In the H2 evolution reaction from NaBH4, the catalysts demonstrated notable catalytic efficiency, with hydrogen generation rates of 2193.17 mL min−1 g−1 for monometallic (Co NPs-HC) and 1205.74 mL min−1 g−1 for bimetallic composition (Co/Ni NPs-HC (80:20)). Additionally, the bimetallic Co-Ni nanocatalyst exhibited stronger stability, maintaining performance over up to six reuse cycles. These findings highlight the potential of the developed nanocatalysts for practical applications in safe hydrogen generation processes, in addition to promoting the circular economy through the reuse and aggregation of value to BSG generated in tons annually by the beer industry.

Resumo em Inglês:

Trace and potentially toxic elements were correlated with landscape indices in the Doce River Basin in Brazil after the Fundão dam collapse. Surface water samples were submitted to the Environmental Protection Agency (EPA3051A) methodology, and figures of merit were evaluated. The certified reference material of trace elements in water was used to check the accuracy. Statistical analyses were applied to identify the factors influencing element concentrations. The predictor variables were land use, soil types, meteorological factors, and longitudinal distances. The total concentration of arsenic, chromium, manganese, nickel, phosphorus, and lead, and dissolved aluminum, copper, and iron exceeded the maximum limits established by Brazilian Resolution, mainly in the upper Doce River during the rainy season. Rainfall was the predictor variable that most affected the response, influenced by dissolved copper and iron. The highest concentration of dissolved aluminum and total phosphorus were obtained during the dry season. Correlation analysis revealed a fair correlation (>0.47-0.67, p < 0.05) among all elements in surface water with soil type, forestry, and forest. The main sources of pollution were total manganese and dissolved aluminum and iron, originating from mining activities. The study emphasizes the impact of the dam collapse during the 2022-2023 period and stresses the importance of improving sewage treatment in the area.

Resumo em Inglês:

Herein, a hydrophobic polydimethylsiloxane-incorporated polyvinylidene fluoride (PDMS/PVDF) nanofiber membrane was prepared by electrospinning method under a certain air humidity. The properties and separation performance of PDMS/PVDF nanofiber membrane were characterized by scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy attenuated total reflectance (FTIR-ATR), X-ray diffraction (XRD) and the oil-water separation test. The results demonstrate that the PDMS/PVDF membrane have better properties and performance than PVDF nanofiber membrane; with the increase in air humidity, electrospinning membrane had superior properties and separation performance. Additionally, when the PDMS concentration was 5.0 wt.%, the membrane had the best hydrophobicity. Moreover, for oil-water separation performance, the maximum flux could reach 1827.8 kg m-2 h-1. In addition, it has a water contact angle of 145.2º and an oil contact angle of 0º. Simultaneously, the membrane prepared under low humidity had continuous structure and little bead structure, which might bring higher crystallinity. Also, after 20 cycles, the separation efficiency could still reach about 95.0%, which showed excellent reusability and long-term stability.

Resumo em Inglês:

The rapid increase in e-waste creates challenges, requiring more efficient recycling methods. This study explores the application of laser-induced breakdown spectroscopy (LIBS) combined with hyperspectral imaging to monitor leaching processes of Ag, Au, Cu and Sn in e-waste recycling. The method involved the use of sequential leaching strategies of printed circuit boards (PCBs), the best strategy was applied using HNO3 for Cu, HCl for Sn and thiourea/Fe(NO3)3 for Ag and Au. Inductively coupled plasma optical emission spectrometry (ICP OES) was used to validate the metal extraction efficiency, achieving recoveries of 100% for Cu and Ag, 97% for Sn and 86% for Au. LIBS spectra showed a strong correlation with the ICP OES data, revealing reductions in the emission signals corresponding to the extracted elements. Hyperspectral imaging provided an analysis of the spatial distribution of trace elements, confirming the progressive extraction of metals. The results indicate that LIBS, associated with multivariate analysis, offers a fast and economical alternative.

Resumo em Inglês:

Presbycusis is a clinical condition related to hearing impairment caused by chronic noise exposure, senescence, or genes that exacerbate the loss of the inner ear. Polycomb Chromobox (CBX) proteins regulate gene expression by targeting the Polycomb repressor complex 1 (PRC1) to histone H3K27me3 sites via their chromodomains, playing a key role in developing presbycusis. This study aims to search for new agents to decrease the progression of the hearing damage pathway CBX4. Initially, a review that identified 17 molecules with reported activity in auditory conditions was done. Molecular dynamics (MD) simulation was performed for the native protein and principal systems employing AMBER20 software. Root mean square deviation (RMSD), RMSF (root mean square fluctuation), solvent accessible surface area (SASA), radius of gyration (RoG) analyses, free energy molecular mechanics generalized born surface area (MMGBSA), and principal components analysis (PCA) calculations were obtained. The main results are that oridonin and curcumin have shown binding energy for the CBX4 protein, with higher affinity than UNC3688. In MDs, the CBX4-oridinin complex showed a more stable profile regarding RMSD and SASA, while the CBX4-curcumin compound evidenced better conformational and energetic stability. In conclusion, oridonin and curcumin could be potential inhibitors for CBX4.

Resumo em Inglês:

Growing consumer demand for sustainable cosmetics has stimulated the integration of plant derived multifunctional actives into sunscreens. Piceatannol, a stilbene with potent antioxidant, anti inflammatory, and photoprotective activities, can potentially enhance UV protection, limiting the concentration of conventional filters. This work assesses the physicochemical compatibility of piceatannol-rich extract in oil-in-water emulsions combined with organic or inorganic UV filters, along with a spilanthol-rich extract incorporated as a putative penetration enhancer. Formulations were characterized by analytical centrifugation, UV-Vis spectroscopy, differential scanning calorimetry, thermogravimetric analysis and accelerated freeze-thaw cycling. Emulsions containing only organic filters remained physically stable, though the filters lowered the volatilization onset by ca. 10 °C. In contrast, inorganic filters provoked immediate darkening, phase instability, and rapid degradation of the bioactives: piceatannol and spilanthol contents fell drastically upon preparation. After 12 days of thermal cycling, piceatannol retention was 40% in the placebo base but became undetectable in all UV filter formulations, while spilanthol persisted at only 34% in mineral filter systems. These findings demonstrate a pronounced incompatibility between piceatannol/spilanthol extracts and inorganic sunscreens, underscoring the need for alternative delivery strategies, such as encapsulation, surface modified minerals or alternative formulations design, to preserve natural actives and achieve truly multifunctional, eco conscious sun care.

Resumo em Inglês:

Natural organic residues (NOR), a residue from extracting organic matter from soils with NaOH, has shown to be an interesting and promising environmental adsorbent, due to its high surface area and porosity, in addition to the diversity of functional groups. In this context, this work developed a material from NOR enriched with CaII and MgII and evaluated its application in lettuce crops irrigated over water in sandy and clay soil. NOR was extracted from a soil collected in Alagoas, Brazil, with 25% organic matter content. The nutrients were inserted into NOR by adsorption in a multielement solution of CaII and MgII (10 mg L-1) at pH 8.0. The highest adsorption rate of NOR (78.92 and 55% for CaII and MgII, respectively) occurred at pH 8.0. The characterization of NOR showed a content of organic matter (OM) = 15.40, C/H ratio = 0.185 and E4/E6 = 2.18 and characteristic bands of OH, C=C and Si-O stretching were observed in the samples. Lettuce cultivation with NOR was conducted in a protected environment for sandy and clayey soils. The results obtained demonstrate the influence of nutrients adsorbed in NOR and water blade on lettuce cultivation, especially in its variables of commercial interest.

Resumo em Inglês:

This study explores potential monoamine oxidase A (MAO-A) inhibitors from secondary metabolites of Spondias species for the treatment of depression. Using molecular docking, the interaction affinity and binding mode of the compounds with the active site of MAO-A were analyzed. Of the 104 metabolites identified, 78 showed significant interactions, with high affinity and specificity. Evaluation of the drug-like properties, according to Lipinski’s Rule of Five (molecular mass, hydrogen bond donors and acceptors and log P coefficient), showed that the majority met the criteria, suggesting good potential as drug candidates. Toxicity predictions were also carried out to ensure the safety of the compounds. In vitro MAO-A inhibition tests with ethanolic extracts of the species with the best docking performance indicated that Spondias metabolites are promising for new treatments for depression.

Resumo em Inglês:

Polyethylene terephthalate (PET) is one of the most widely used polymers worldwide, particularly in packaging; however, its poor recyclability greatly contributes to plastic pollution. This study investigates an alternative valorization pathway through partial depolymerization with glycerol under both microwave and conventional heating conditions, without the use of catalysts or solvents. Both methods produced white, brittle solids with distinct physicochemical properties. Thermal analysis revealed an initial mass loss (130-220 °C) due to residual glycerol, followed by degradation steps indicative of shorter polymer chains. Additionally, the lower glass transition and melting points, along with sharper crystallization peaks, support the idea of chain scission and improved nucleation. Spectroscopic analyses identified new polyester structures derived from glycerol and PET, coexisting with unmodified PET. The modified material demonstrated promising results for Rhodamine-B adsorption, with high retention (> 97%) over multiple filtration cycles. This environmentally friendly, scalable approach effectively converts PET waste into functional materials, supporting the principles of green chemistry and the circular economy.

Resumo em Inglês:

Tuberculosis remains a significant global health concern, particularly due to the increasing prevalence of drug-resistant strains. In this work, a series of 2-(quinoline-4-yloxy)acetamides was synthesized and evaluated for antimycobacterial activity, aiming to advance the understanding of structure-activity relationships (SAR) within this scaffold. Variations at the quinoline core and the aryl moiety of the acetamide side chain resulted in distinct biological profiles, with SAR analysis revealing that small to moderate hydrophobic substituents at the 4-position of the aryl ring enhanced potency, while bulky or strongly electron-withdrawing groups reduced activity, likely due to steric or electronic effects. Notably, the lead compound exhibited a minimum inhibitory concentration of 0.80 µM against Mycobacterium tuberculosis H37Rv, representing more than a 2.8-fold increase in potency compared to isoniazid under identical experimental conditions. Furthermore, this molecule demonstrated no detectable cytotoxicity in HepG2 (human caucasian hepatocytes carcinoma) and Vero (African green monkey kidney) cell lines up to 20 µM, resulting in selectivity indices exceeding 25, and exhibited favorable solubility under acidic conditions (156 µM at pH 1.2). These findings indicate that the 2-(quinoline-4-yloxy)acetamide scaffold holds promise for further development and support the rational design of new candidates for the treatment of tuberculosis, potentially contributing to strategies aimed at overcoming the limitations of current therapies.

Resumo em Inglês:

This study investigated the synergistic characteristics of co-hydrothermal carbonization (co-HTC) of sewage sludge (SS) and wheat straw (WS). Co-HTC of SS and WS synergistically promoted the conversion of organic matter into combustible hydrochar components. The synergistic coefficients for hydrochar yield (YHC), energy recovery efficiency (REN), carbon recovery efficiency (RC) and hydrogen recovery efficiency (RH) first increased and then decreased as the WS blending ratio or hydrothermal carbonization (HTC) temperature increased. Additionally, blending WS or increasing the HTC temperature shifted the main combustion process of hydrochar to the low-temperature region. The average activation energy of hydrochar combustion first decreased and then increased as the WS blending ratio increased. However, the average combustion activation energies of hydrochars prepared via HTC at 200, 230 and 260 °C were essentially identical (160.61, 161.88, and 161.04 kJ mol-1, respectively), with a relative difference of < 1%. Maintaining an HTC temperature of 200 °C avoids the higher energy input required for elevated temperatures (230 or 260 °C), which is crucial for reducing the industrial application costs of HTC while preserving hydrochar quality. Consequently, from the perspective of energy consumption, 200 °C is more suitable for the HTC. The minimum average activation energy for hydrochar combustion (160.61 kJ mol-1) was achieved at a SS:WS mass ratio of 2:1 and an HTC temperature of 200 °C. These research findings provide a theoretical basis for the energy-oriented utilization of SS and waste biomass.

Resumo em Inglês:

A better understanding of the problem of protein aggregation encouraged the development of computational tools to help study this phenomenon. Some studies indicate that short segments of amino acids found in amyloid precursor proteins may be involved in the formation of these aggregations. The creation of precise techniques for identifying regions that are prone to aggregation is one of the present issues facing the bioinformatics community. In our earlier work, we developed Magre-I using machine learning techniques. Using a consensus model for classification, this approach made it possible to predict aggregation regions based on the primary amino acid sequence of proteins. We now present an improved method, called Magre-II, which makes use of the three-dimensional (3D) structure of proteins and experimental annotations of aggregation by using a neighborhood sphere analysis model for training and predictions. We show that Magre-II has a high potential for predicting regions that are prone to protein aggregation by comparing it with other commonly used predictors. The obtained scores were as follows: Magre-II (78.2%), Aggrescan3d (76.7%), Waltz (67.4%), and Tango (73.1%) for alpha-synuclein.

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Anodizing is one of the methods to improve the corrosion resistance of aluminum alloy. Anodic oxide film was prepared on 2024 aluminum alloy by constant current anodic oxidation method. The selected electrolyte was tartrate-sulfuric-acid electrolyte which adding magnesium phosphate. Anodic oxide film was prepared by changing the anodic oxidation temperature, current, time and other process parameters. The morphology, elemental composition and phase of anodic oxide film before and after optimization were characterized by SEM (scanning electron microscopy), XRD (X-ray diffraction) and EDS (energy dispersive spectroscopy), the corrosion resistance of anodic oxide film was characterized by electrochemical test, salt spray experiment and immersion aging experiment. The results showed that the thickness of the film after adding magnesium phosphate was higher than that before adding magnesium phosphate. Electrochemical impedance spectroscopy showed that the impedance modulus at 0.01 Hz is one order of magnitude higher after adding magnesium phosphate than before adding magnesium, and two orders of magnitude higher than the bare substrate, indicating that the corrosion resistance was greatly enhanced. The anodic oxide film obtained by adding magnesium phosphate to the electrolyte greatly improved the corrosion resistance, which provide an effective idea for the corrosion protection of aluminum alloy.

Resumo em Inglês:

Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system, characterized by demyelination and inflammation. Although treatments are available, they have serious adverse effects and are expensive. Ursolic acid (UA) has anti-inflammatory and neuroprotective properties, but its low solubility hinders its application. This study developed and characterized a ursolic acid with poly-β-cyclodextrin (UA/pβCD) complex and evaluated its immunomodulatory potential in vitro and in vivo. Fourier transform infrared spectroscopy, thermal analyses, and phase solubility experiments confirmed the complexation. The complex improved UA solubility and thermal stability, reduced cytotoxicity in macrophage cell lines, and decreased nitric oxide production. In the experimental autoimmune encephalomyelitis (EAE) model, UA and UA/pβCD reduced neurological disability scores, indicating an attenuation of the inflammatory response. The complex group showed lower levels of IL-12p70 in the brain and spinal cord. These results indicate that the UA/pβCD complex is a promising strategy for the treatment of MS.

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Graphene oxide (GO) production via electrochemical exfoliation has attracted a lot of attention because it is a green, safe, and efficient technique with good quality and greater scalability compared to the conventional synthesis routes. In this study, we present the development of a low-cost (ca. US$50), automated electrochemical reactor for the GO synthesis via electrochemical exfoliation of graphite. The system is based on an Arduino-controlled reactor capable of modulating key synthesis parameters, including voltage levels, duration, and the number of cycles, enabling precise process control. A 24-1 factorial design was employed to investigate the influence of process variables-particularly the electrolyte concentration, voltage magnitude, electrolysis time, and number of voltage cycles-on the structural, morphological, and colloidal properties of GO. The results demonstrate that optimizing the electrolyte concentration and the reaction time flakes with uniform size distribution (11.38 ± 0.48 μm) were obtained. Increasing the number of cycles enhances exfoliation efficiency, yielding larger (ca. 35 μm) and thinner (3-6 nm) flakes with higher oxidation degrees and improved colloidal stability, as evidenced by zeta potential measurements reaching -49 mV. Temperature monitoring revealed that the cycling strategy helps lower the reaction temperature by 5 ºC, which promotes more controlled oxidation and exfoliation of graphite. This work highlights a versatile and scalable approach to GO production with tunable properties, offering an environmentally friendly and reproducible alternative to conventional chemical oxidation methods.

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To overcome the non-specific entry of cisplatin and other transition metal complexes into both normal and cancer cells, we developed folic acid-modified halloysite nanotubes (HNTs-FA) and magnetic halloysite nanotubes (MHNTs-FA) as targeted drug carriers. These carriers were loaded with an anionic palladium complex, [Pd(dipic)2]2- (dipic: dipicolinic acid), and tested on colon cancer cells. On folate receptors (FRs)-positive HT29 cells, MHNTs-FA-[Pd(dipic)2]2- showed significant cytotoxicity, reducing cell viability below 50% at low concentrations. While free [Pd(dipic)2]2- and cisplatin were ineffective at these concentrations, MHNTs-FA performed better due to enhanced folate receptor targeting and the presence of Fe3O4 nanoparticles. On FR-negative LoVo cells, results suggested the transferrin receptor-1 (TfR1) provided an alternate entry path for MHNTs-FA. Real-time polymerase chain reaction (PCR) confirmed the increased apoptosis via the mitochondrial pathway, with MHNTs-FA-[Pd(dipic)2]2- boosting the Bak1/Bclx ratio by 1500-fold and raising Caspase-3 expression. Additionally, it suppressed AKT1 gene expression, lowering drug resistance. Flow cytometric analysis also confirmed the ability of MHNTs-FA-[Pd(dipic)2]2- to induce apoptosis in HT29 cells. Importantly, modified HNTs did not cause oxidative stress in erythrocytes. These findings highlight MHNTs-FA as an efficient, targeted delivery system that enhances the therapeutic effects of palladium complexes while minimizing harm to healthy cells.

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Leishmaniasis is a neglected tropical disease of global relevance, and the emergence of parasite resistance highlights the urgent need for new therapeutic strategies. This study aimed to identify compounds with potential antileishmanial activity through virtual screening and in vitro validation. Seventy-seven Leishmania proteins were evaluated, leading to the identification of triosephosphate isomerase (TIM, PDB ID: 2VXN) as a promising therapeutic target. TIM was screened against more than 6,500 bioactive compounds, resulting in two potential inhibitors: ZINC9829539 and ZINC4270223. Molecular dynamics simulations revealed that both compounds established stable interactions with TIM, although with lower binding affinity compared to the crystallographic ligand phosphoglycolohydroxamic acid (PGH). In vitro assays were performed using THP-1-derived macrophages infected with intracellular amastigotes of Leishmania infantum, L. braziliensis, and L. amazonensis. The compounds exhibited cytotoxic concentrations between 15 and 30 µM, comparable to amphotericin B. Inhibitory concentrations ranged from 10.4-28 µM for ZINC4270223 and 22.1-26.6 µM for ZINC9829539. Selectivity indices ranged from 0.57-0.59 and 0.98-2.66, respectively, indicating limited parasite selectivity. Despite moderate efficacy, this study demonstrates the utility of virtual screening in identifying novel antileishmanial candidates. Further structural optimization may enhance the selectivity and potency of these compounds, making them more viable for therapeutic development against leishmaniasis.

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Considering the plan to increase the mixture of biodiesel in diesel oil (currently 14% in Brazil), it is becoming necessary to know the composition of exhaust gases. This study shows that most recent articles indicate that biodiesel is a suitable alternative in these circumstances, although they point out that it can have harmful effects, such as an increase in some emissions, for example carbonyls. A diesel utility van was used fueled by different mixtures of 0, 10, 15, 20 and 30% of biodiesel added to diesel, under a protocol test using a dynamometer. The emissions were collected from a constant volume sampler and transferred to a 4 m3 polytetrafluoroethylene (PTFE) reaction chamber to enable the formation of secondary pollutants, which allowed the study to be carried out without the influence of meteorological parameters. The results are highlighted for each of the pollutants and show the differences in the composition of the exhaust gases when the fuel is changed. No significant changes were observed in carbonyls emissions, but a clear reduction for benzene, toluene, ethylbenzene and xylenes (BTEX) and alkyl-PAHs (polycyclic aromatic hydrocarbons), and an increase in nitro-HPA were detected. Fine particles (< 1.8 µm) also showed an increase, but nano particles (< 180 nm) demonstrated a decrease.

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The global population of dogs and cats has grown, boosting the revenue of the pet industry, and has raised concerns among their owners regarding the quality of food. Lipids are essential in the diet of dogs and cats, supporting overall health when present within recommended limits. Lipid oxidation represents a challenge as it compromises the quality and safety of food. Antioxidants play an important role in minimizing these impacts and ensuring food stability. Therefore, this study analyzed the composition of fatty acids and antioxidants in dry extruded food for dogs and cats. The values of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were determined, highlighting the importance of the omega-6/omega-3 ratio in animal health. It was observed that all foods met the minimum recommended limits for fatty acids. Antioxidant analysis revealed the presence of butylhydroxyanisole (BHA), butylhydroxytoluene (BHT) and ethoxyquin within permitted limits. The peroxide index (PI) was higher in dog foods. The results reinforce the need for an adequate balance between fatty acids and strategies to control lipid oxidation, aiming to guarantee the quality of industrialized foods for dogs and cats.

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4-Mercaptobenzoic acid (4-MBA) adsorption behavior was studied through an adsorption isotherm with surface-enhanced Raman scattering as the spectroscopic probe molecule, using chitosan-protected gold nanoparticles (AuNP). As the surface coverage was lower, 4-MBA molecules were reoriented, which led to the carboxylate group interaction with AuNP, besides the thiolate interaction, based on experimental and density-functional theory-based results. The adsorption process was fitted considering Langmuir isotherms, and a Gibbs energy of adsorption of -25 kJ mol-1 was obtained.

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Neuropsychiatric disorders often involve dysregulation of serotonergic and dopaminergic pathways. This study applied machine learning (ML) with quantitative structure-activity relationship (QSAR) methods to predict the bioactivity (-log half-maximal inhibitory concentration (pIC50)) of compounds targeting both receptor families, aiming to identify multitarget inhibitors among US Food and Drug Administration (FDA)-approved drugs. A dataset of 5,628 compounds with experimental IC50 values was obtained from ChEMBL and encoded with PubChem fingerprints. Random Forest and Extreme Gradient Boosting models were trained, optimized, and evaluated with 5-fold cross-validation, and Shapley Additive Explanations (SHAP) values were used for interpretation. After outlier removal and descriptor selection, models achieved coefficient of determination (R2) test ca. 0.69 and were used to screen over 1,500 approved drugs. A total of 162 were predicted to have dual bioactivity (pIC50 > 6, coefficient of variation < 1%), including antipsychotics, adrenergic agonists (e.g., epinephrine), dopamine agonists (e.g., levodopa), antihistamines (e.g., cyproheptadine), antiemetics (e.g., droperidol), ergot alkaloids (e.g., ergotamine), antibiotics (e.g., penicillin G), and lipid-lowering agents (e.g., pravastatin). Key molecular descriptors indicated the relevance of nitrogen-containing fragments and conjugated aromatic substructures for dual receptor binding. These results provide a computational framework for repurposing drugs and guiding experimental validation in neuropsychiatric research.