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Background/Objectives: Liposomes are promising carriers for enhancing antibiotic delivery, but their stability under various stress conditions is crucial for clinical applicability. Methods: This study aimed to evaluate the physicochemical and antimicrobial stability of streptomycin-loaded liposomes subjected to mechanical (bath ultrasonication, probe ultrasonication, ultra-turrax homogenization), thermal (freezing, heating), and chemical (H2O2, Triton X-100, sodium dodecyl sulfate—SDS) stressors. Results: Isolated mechanical stresses (probe ultrasonication, ultrasonic bath, and ultra-turrax) did not significantly affect hydrodynamic diameter (DH), polydispersity index (PdI), or Zeta potential (ZP) (p > 0.05). In contrast, combined ultrasound–freezing stress induced marked destabilization, with DH increasing from ~110 nm to 362 nm (Lc0uf) and from 109 nm to 334 nm (Lc1uf), accompanied by PdI increases from ~0.13 to 0.37–0.41 and a ZP shift in Lc1uf from −43.1 mV to −60.1 mV. Thermal exposure at 75 °C and freezing at −30 °C caused no significant changes in DH or PdI, whereas freezing at −80 °C led to severe destabilization, with over fourfold increases in DH and fivefold increases in PdI; the cholesterol-free formulation (Lc0t−80) reached ~664 nm and a PdI of 0.609. Chemical oxidation with 1% H2O2 did not affect DH, PdI, or ZP, while surfactants (1% Triton X-100 and 1% SDS) significantly altered PdI and ZP in a cholesterol-dependent manner. MIC assays showed that formulations stressed by freezing at −80 °C or by combined ultrasound–freezing retained activity against Escherichia coli (MIC = 50 µg/mL), whereas SDS abolished activity. For Staphylococcus aureus, all stressed formulations remained active, and SDS reduced the MIC from 12.5 to 5.625 µg/mL. Conclusions: These findings demonstrate the robustness and stress-specific stabilization of these liposomal formulations, confirming that the antibiotic’s activity is preserved, which highlights their potential for therapeutic use.

Early plants began colonizing earth about 450 million years ago. During the process of coevolution, their metabolic cellular pathways produced a myriad of natural chemicals, many of which remain uncharacterized biologically. Popular preparations containing some of these molecules have been used medicinally for thousands of years. In Brazilian folk medicine, plant extracts from the bamboo plant Guadua paniculata Munro have been used for the treatment of infections and pain. However, the chemical basis of these therapeutic effects has not yet been identified. Here, we performed protein biochemistry and downstream pharmacological assays to determine the mechanisms underlying the anti-inflammatory and antinociceptive effects of an aqueous extract of the G. paniculata rhizome, which we termed AqGP. The anti-inflammatory and antinociceptive effects of AqGP were assessed in mice. We identified and purified a protein (AgGP), with an amino acid sequence similar to that of thaumatins (~20 kDa), capable of repressing inflammation through downregulation of neutrophil recruitment and of decreasing hyperalgesia in mice. In conclusion, we have identified the molecule and the molecular mechanism responsible for the anti-inflammatory and antinociceptive properties of a plant commonly used in Brazilian folk medicine.

Central composite design (CCD) is a statistical experimental design technique that utilizes a combination of factorial and axial points to study the effects of multiple variables on a response. This study focused on optimizing hydrogel formulations for 3D printing using CCD. Three biopolymers were selected: sodium alginate (SA), gelatin (GEL), and carboxymethyl cellulose (CMC). The maximum and minimum concentrations of each polymer were established using a Google Scholar search, and CCD was employed to generate various combinations for hydrogel preparation. The hydrogels were characterized in accordance with their swelling degree (SD) in phosphate-buffered saline (PBS) and Dulbecco’s Modified Eagle Medium (DMEM), as well as their printability in 2D and 3D assays. The formulation consisting of 7.5% SA, 7.5% GEL, and 2.5% CMC exhibited the best swelling properties and exceptional printability, surpassing all other tested formulations. This study highlights the effectiveness of design of experiment methodologies in accelerating the development of optimized hydrogel formulations for various applications in 3D printing and suggests avenues for future research to explore their performance in specific biological contexts.

Parkinson’s disease (PD) is a progressive neurodegenerative condition that affects the Central Nervous System (CNS). Insect venoms show high molecular variability and selectivity in the CNS of mammals and present potential for the development of new drugs for the treatment of PD. In this study, we isolated and identified a component of the venom of the social wasp Parachartergus fraternus and evaluated its neuroprotective activity in the murine model of PD. For this purpose, the venom was filtered and separated through HPLC; fractions were analyzed through mass spectrometry and the active fraction was identified as a novel peptide, called Fraternine. We performed two behavioral tests to evaluate motor discoordination, as well as an apomorphine-induced rotation test. We also conducted an immunohistochemical assay to assess protection in TH+ neurons in the Substantia Nigra (SN) region. Group treated with 10 μg/animal of Fraternine remained longer in the rotarod compared to the lesioned group. In the apomorphine test, Fraternine decreased the number of rotations between treatments. This dose also inhibited dopaminergic neuronal loss, as indicated by immunohistochemical analysis. This study identified a novel peptide able to prevent the death of dopaminergic neurons of the SN and recover motor deficit in a 6-OHDA-induced murine model of PD.

Kraft paper, commonly known as brown paper, has been widely used in the preservation of various food products and is increasingly explored in the development of active packaging materials with antimicrobial functionality by incorporating metal nanoparticles. This study aimed to comparatively investigate the surface modification of Kraft paper with silver nanoparticles (AgNPs) using dip-coating and drop-casting techniques. AgNPs were produced via green synthesis and incorporated onto the surface of Kraft paper samples. The modified samples were characterized using physicochemical techniques, including atomic force microscopy (AFM), Raman spectroscopy and light microscopy, as well as nanomechanical characterization via force spectroscopy. The antimicrobial activity of the modified papers was assessed using the disk diffusion method. The results demonstrated that the modification techniques resulted in distinct surface characteristics. Samples treated with the drop-casting method exhibited the highest AgNP surface loading; however, this was accompanied by pronounced surface heterogeneity and a tendency toward reduced load-bearing capacity. Overall, the findings indicate that the choice of deposition technique plays a key role in controlling nanoparticle distribution and surface properties. Within the limitations of the techniques evaluated, the incorporation of nanomaterials with potential antimicrobial activity into Kraft paper may offer opportunities for the development of active food packaging, although further optimization is required.

Background/Objectives: In recent years, silver nanoparticles (AgNPs) have garnered significant attention due to their potent antimicrobial properties, which hold promise for various applications. However, concerns about their potential toxicity have also emerged, particularly regarding their impact on human and animal health. This study investigates the acute toxicological effects of AgNPs synthesized using a green route with an aqueous extract of a native Cerrado plant (AgNPs-Cb) in mice. Methods: The AgNPs-Cb were intravenously administered at a concentration of 64 µM, and the mice were euthanized after 24 h for the collection of blood and organ samples (liver, spleen, kidneys, and lungs) for hematological, biochemical, and histological analyses. Results: Hematological analysis, including complete blood count (CBC) and differential leukocyte count, showed no statistically significant alterations in the groups treated with AgNPs-Cb, Cb extract, and Ag+, compared with the control group (p < 0.05). Notably, only the Ag+ group exhibited a significant increase in red blood cell count and hematocrit levels, suggesting that the nanoformulation of silver might mitigate the hematological impact seen with free silver ions. Biochemical analyses of liver and kidney function markers also revealed no significant differences across the treatment groups. Conclusions: These findings indicate that AgNPs-Cb may offer a safer alternative for antimicrobial applications, reducing the risk of acute toxicity in mammals while maintaining efficacy against pathogens. Further studies are needed to explore the underlying mechanisms and long-term effects of AgNPs-Cb exposure.

This study investigates the development and characterization of bioactive films incorporating silver nanoparticles (AgNPs) into biocompatible polymers, namely alginate and chitosan, fabricated using two methods, spin-coating and drop-casting, and aiming to enhance their antimicrobial properties. Dynamic light scattering (DLS) and electrophoretic mobility (EM) of the film precursor solutions revealed significant changes in the nanoparticles’ size and Zeta potential (ZP), reflecting the influence of polymer coatings. Alginate contributed to high electrostatic stability due to its negative charge, while chitosan facilitated specific interactions with negatively charged surfaces. Raman spectroscopy revealed that spin-coating conditions did not successfully result in film formation, highlighting the need for further optimization. Therefore, subsequent characterization studies were conducted only for the films formed by drop-casting. Topographical and nanomechanical assessments of these drop-cast films, using atomic force microscopy (AFM) and force spectroscopy, demonstrated that AgNPs reduced adhesion and elasticity in alginate films, while increasing rigidity and adhesion in chitosan-based films. Antimicrobial tests confirmed the efficacy of AgNPs in both precursor solutions and polymer films, with chitosan-based films that retained structural integrity, which makes them suitable for prolonged applications, while alginate films displayed rapid gelation upon hydration, potentially advantageous in short-term applications. The findings underscore the potential of these biopolymer-AgNP composites in creating antimicrobial materials for food packaging, wound dressings, and other biomedical applications. However, challenges related to film deposition methods, such as spin-coating, require further optimization to improve film formation and reproducibility.

Background Influenza A virus (IAV) causes respiratory disease in pigs and is a major concern for public health. Vaccination of pigs is the most successful measure to mitigate the impact of the disease in the herds. Influenza-based virosome is an effective immunomodulating carrier that replicates the natural antigen presentation pathway and has tolerability profile due to their purity and biocompatibility. Methods This study aimed to develop a polyvalent virosome influenza vaccine containing the hemagglutinin and neuraminidase proteins derived from the swine IAVs (swIAVs) H1N1, H1N2 and H3N2 subtypes, and to investigate its effectiveness in mice as a potential vaccine for swine. Mice were immunized with two vaccine doses (1 and 15 days), intramuscularly and intranasally. At 21 days and eight months later after the second vaccine dose, mice were euthanized. The humoral and cellular immune responses in mice vaccinated intranasally or intramuscularly with a polyvalent influenza virosomal vaccine were investigated. Results Only intramuscular vaccination induced high hemagglutination inhibition (HI) titers. Seroconversion and seroprotection (> 4-fold rise in HI antibody titers, reaching a titer of ≥ 1:40) were achieved in 80% of mice (intramuscularly vaccinated group) at 21 days after booster immunization. Virus-neutralizing antibody titers against IAV were detected at 8 months after vaccination, indicating long-lasting immunity. Overall, mice immunized with the virosome displayed greater ability for B, effector-T and memory-T cells from the spleen to respond to H1N1, H1N2 and H3N2 antigens. Conclusions All findings showed an efficient immune response against IAVs in mice vaccinated with a polyvalent virosome-based influenza vaccine.

Food residues are a promising resource for obtaining natural pigments, which may replace artificial dyes in the industry. However, their use still presents challenges due to the lack of suitable sources and the low stability of these natural compounds when exposed to environmental variations. In this scenario, the present study aims to identify different food residues (such as peels, stalks, and leaves) as potential candidates for obtaining natural colorants through eco-friendly extractions, identify the colorimetric profile of natural pigments using the RGB color model, and develop alternatives using nanotechnology (e.g., liposomes, micelles, and polymeric nanoparticles) to increase their stability. The results showed that extractive solution and residue concentration influenced the RGB color profile of the pigments. Furthermore, the external leaves of Brassica oleracea L. var. capitata f. rubra, the peels of Cucurbita maxima, Cucurbita maxima x Cucurbita moschata, and Beta vulgaris L. proved to be excellent resources for obtaining natural pigments. Finally, the use of nanotechnology proved to be a viable alternative for increasing the stability of natural colorants over storage time.

Background/Objectives: This study aimed to develop liposomes derived from lipids obtained from red blood cell membranes for potential use in antitumor applications. Hemoglobin hydrolysates exhibiting peptides with known antitumor activities were encapsulated within these liposomes. Methods: The developed liposomal systems were characterized by their physicochemical properties, including size, surface charge, and encapsulation efficiency, and tested in vitro against 4T1 breast cancer cells and NIH3T3 fibroblasts. Results: Results indicated that the liposomes achieved effective encapsulation (88.9%), with nanometer-scale sizes (ranging from 140.7 nm for Blank-Liposomes to 658.3 nm for Pep-Liposomes) and stable colloidal properties. Conclusions: Although cytotoxicity was limited, the use of liposomes from endogenous components, such as red blood cells, demonstrates promise as a complementary approach in anticancer therapy.