Search Results (34,292)

Developing eco-friendly metal oxide nanoparticles (NPs) with plant-based reducing and stabilizing agents offers a sustainable alternative to traditional chemical methods. Nonetheless, the detailed mechanisms by which phytochemicals influence NPs formation, antimicrobial properties, and cytocompatibility remain poorly understood, especially in systems mediated by Vaccinium. This study aimed to synthesize TiO₂ NPs and ZnO NPs using Vaccinium corymbosum (blueberry) extract, analyze their structural and surface characteristics, assess their antimicrobial effectiveness and cytotoxicity, and explore potential molecular mechanisms through computational docking. ZnO NPs were produced via alkaline precipitation (pH 12) from ZnCl₂, while food-grade TiO₂ was mixed with blueberry extract. A comprehensive characterization was carried out using techniques like X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, transmission and scanning electron microscopy (TEM/SEM), dynamic light scattering (DLS), and high-performance liquid chromatography (HPLC) for polyphenol profiling. The antimicrobial activity was tested against Escherichia coli and Salmonella Typhimurium, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. Cytotoxicity was assessed using Gallus gallus domesticus leukocytes and Artemia salina bioassays, and molecular docking simulations were performed to examine polyphenol interactions with the bacterial DNA gyrase subunit B (GyrB). XRD analysis confirmed the presence of wurtzite ZnO (with a crystallite size of 18.2 nm) and anatase TiO₂ (12.8 nm after functionalization). HPLC identified key polyphenols, including quercetin, cyanidin, malvidin, and cyanidin-3-glucoside, with patterns indicating stronger adsorption onto TiO₂ NPs surfaces. ZnO NPs showed higher antimicrobial effectiveness (>90% inhibition at 2 mg/mL; MIC 0.5–1 mg/mL) compared to TiO₂ (72% inhibition at 16 mg/mL; MIC 8–16 mg/mL). Cytotoxicity results indicated concentration-dependent effects. Molecular docking simulations revealed favorable binding energies (−6.2 to −8.4 kcal/mol) for blueberry polyphenols with GyrB, suggesting potential synergistic antimicrobial effects and ROS production. The study highlights a successful green synthesis of bioactive TiO₂ NPs and ZnO NPs using Vaccinium corymbosum extract, where polyphenol surface functionalization enhances both colloidal stability and biological activity. This comparative research offers mechanistic insights into how polyphenol-coated NPs work and supports the development of eco-friendly antimicrobial oxide nanomaterials. Full article

Wound healing in cosmetological and aesthetic surgery extends beyond tissue closure to achieving rapid regeneration, minimal scarring, and restoration of functional skin architecture. However, conventional wound care strategies inadequately regulate the complex wound microenvironment required for optimal cosmetic outcomes, leading to prolonged healing times and suboptimal aesthetic results, which can negatively impact patient satisfaction and increase the risk of complications. Phytochemicals exhibit multifunctional bioactivities, such as antioxidant, anti-inflammatory, antimicrobial, and pro-regenerative effects, but their clinical translation faces obstacles due to poor solubility, stability, and bioavailability. Nanotechnology-based delivery systems have emerged as a critical enabling strategy to overcome these limitations. This narrative review provides an updated, mechanistically integrated synthesis of phytochemical-loaded nanotherapeutics, including polymeric nanoparticles, nanohydrogels, nanofibers, and lipid- and vesicle-based systems, with a specific focus on their roles in modulating key wound-healing pathways, such as inflammation resolution, angiogenesis, collagen remodelling, and re-epithelialization. Evidence from preclinical studies consistently demonstrates that nano-enabled phytochemicals enhance therapeutic efficacy, improve skin penetration, and contribute to superior cosmetic outcomes, particularly by reducing fibrosis and scar formation. However, critical gaps remain, including limited high-quality clinical evidence, a lack of standardized formulation design, variability in reported outcomes, and unresolved concerns regarding long-term safety and regulatory translation. Taken together, the key insight of this review is that phytochemical-loaded nanotherapeutics represent a promising but still transitional strategy, biologically compelling at the preclinical level yet clinically under-validated. Bridging this gap requires rigorously designed clinical trials, quantitative outcome reporting, and balanced regulatory frameworks. Advancing these areas will be essential to translate nano-enabled phytochemicals from experimental systems into reliable, evidence-based solutions for cosmetological wound management. Full article

Background/Objectives: Acute otitis media (AOM) remains a leading cause of pediatric morbidity and a primary indication for antibiotic prescription worldwide. Given the potential for serious complications and the evolving landscape of antimicrobial resistance, up-to-date epidemiological data on causative bacteria are essential. This study aimed to assess the global prevalence of major bacterial pathogens in pediatric AOM and evaluate variations across geographic regions and temporal periods (pre-2000 vs. post-2000). Methods: A systematic search of PubMed, Embase, and Web of Science (1980–2025) was conducted to identify studies reporting middle ear fluid culture results in children (0–18 years) with AOM. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 45 studies encompassing 16,305 AOM episodes were included. Data were synthesized from North America, Europe, the Middle East, Asia, Oceania, and Africa. Pooled prevalence estimates and 95% confidence intervals (CIs) were calculated using a random-effects model, and heterogeneity was assessed via the I² statistic. Results: The overall pooled culture-positive rate was 66.6% (95% CI, 62.2–70.8%). Regional pooled estimates ranged from 56.1% in the Middle East (95% CI, 40.3–70.6%; underlying counts, 3776/10,652) to 77.5% in North America (95% CI, 68.2–84.7%; underlying counts, 1567/2125). Streptococcus pneumoniae was the most prevalent pathogen, with a pooled proportion of 29.0% (95% CI, 26.3–31.8%), followed by Haemophilus influenzae (22.3%; 95% CI, 19.3–25.6%) and Moraxella catarrhalis (4.6%; 95% CI, 3.4–6.1%). While S. pneumoniae remained the leading pathogen in most regions, H. influenzae showed marked geographic variability, peaking in the Middle East at 27.5% (95% CI, 17.0–41.2%; underlying counts, 2280/10,652) and reaching its lowest level in Asia at 13.5% (95% CI, 7.8–22.4%; underlying counts, 336/1854). The pooled culture-positive rate declined from 72.5% before 2000 (95% CI, 67.6–76.9%; underlying counts, 5769/8199) to 59.4% in 2000 and later (95% CI, 52.1–66.3%; underlying counts, 6661/15,707), although S. pneumoniae remained the predominant isolate in both periods. Conclusions: S. pneumoniae remains the primary bacterial driver of pediatric AOM globally. However, the observed geographic disparities and the temporal shift in pathogen prevalence following pneumococcal conjugate vaccine (PCV) introduction underscore the necessity for region-specific empirical antibiotic selection. These findings highlight the critical need for sustained microbiological surveillance to inform future vaccination and treatment strategies. Full article

Fusarium head blight (FHB), caused by Fusarium graminearum, is a devastating wheat disease leading to significant yield loss and mycotoxin contamination. This study elucidated the biocontrol mechanism of Bacillus velezensis 20507 fermentation broth against FHB during wheat infection. The broth exhibited strong, time-dependent antifungal activity in vitro, with optimal growth suppression (inhibition rates up to 75%) achieved using broth fermented for 3–7 days. In planta experiments confirmed its efficacy in alleviating disease symptoms. Employing a dual RNA-seq strategy, we analyzed the tripartite interaction between the biocontrol agent, pathogen, and wheat host. Transcriptomic analysis revealed that the broth directly suppressed the pathogen, causing 1510 differentially expressed genes (DEGs, predominantly down-regulated) and disrupting pathways related to carbohydrate metabolism and cell wall integrity. In wheat, the fermentation broth of B. velezensis 20507 counteracted F. graminearum infection by reprogramming the host transcriptome. KEGG analysis during co-inoculation showed that the broth up-regulated defense-related pathways involved in energy, hormone signaling, and cellular maintenance, while down-regulating primary metabolic pathways, indicating a resource reallocation strategy. Furthermore, transcriptomic analysis revealed that the broth alone primed the wheat defense system, and this primed state significantly enhanced the defense response upon pathogen challenge. Untargeted metabolomics identified key antimicrobial compounds, including lipopeptides and the macrolide Macrolactin A. Bioassay-guided fractionation isolated two active fractions (Fr A and Fr B) with potent antifungal activity. This integrated multi-omics study demonstrates that B. velezensis 20507 combats FHB through a coordinated dual mechanism: direct inhibition of the fungus via specific metabolites like Macrolactin A, and simultaneous reprogramming of the host defense and metabolic landscape. These findings provide a scientific foundation for developing this strain as an effective biocontrol agent. Full article

Background: Acinetobacter baumannii is a non-fermenting Gram-negative bacillus responsible for severe nosocomial infections, particularly in intensive care units (ICUs). The increasing prevalence of multidrug-resistant (MDR) and carbapenem-resistant A. baumannii (CRAB) strains has become a significant challenge for infection control and antimicrobial therapy worldwide. Objectives: This study aimed to analyze the antimicrobial susceptibility patterns of clinical A. baumannii isolates recovered from a multi-profile hospital in years 2020–2024 in Lodz, Poland. Methods: Clinical isolates from various specimen types (blood, urine, wound swabs, biopsies, sputum, and bronchoalveolar lavage fluid) were obtained during routine microbiological diagnostics. Identification was performed using MALDI-TOF MS. Antimicrobial susceptibility testing (AST) was conducted using the automated VITEK^®2 system with EUCAST/CLSI interpretive criteria. Minimum inhibitory concentrations (MICs) for colistin were determined by broth microdilution. Carbapenemase production was assessed using the Carbapenem Inactivation Method (CIM) and immunochromatographic assays for OXA-23, OXA-40/58, and NDM detection. Results: A total of 244 A. baumannii isolates were recovered over the study period. Susceptibility to carbapenems (meropenem, imipenem) declined markedly, with resistance exceeding 90% by 2023–2024. Aminoglycosides exhibited variable activity, with gentamicin demonstrating the highest susceptibility rates (up to 88% in 2022). Resistance to ceftazidime and cefepime remained consistently high (>90% in 2023–2024). No fully susceptible isolates were identified for ciprofloxacin. Conclusions: The high prevalence of CRAB strains highlights the urgent need for effective infection control measures, optimized antimicrobial stewardship, and consideration of novel treatment options in the clinical setting. Full article

This study presents an exploratory reinforcement learning (RL)-based simulation framework for examining antimicrobial resistance (AMR) dynamics under repeated exposure to a non-antibiotic stressor, using copper as a simplified model compound. The objective is not to provide mechanistic or predictive insight into microbial evolution, but to evaluate how alternative sequential decision-making strategies perform within a constrained and transparent simulation environment. Three agent strategies were compared: random action selection, a rule-based heuristic, and a tabular Q-learning agent. Simulations were conducted over fixed 40-cycle episodes in which agents adjusted copper exposure in response to evolving resistance-related state variables. Across experimental runs, the Q-learning agent exhibited lower cumulative resistance burden, measured by area under the curve (AUC) of minimum inhibitory concentration (MIC) trajectories for chloramphenicol and polymyxin B, while maintaining lower cumulative copper exposure relative to baseline strategies. The rule-based agent demonstrated intermediate performance, whereas the random agent showed greater variability and less stable trajectories. These findings reflect differences in simulated control behavior within a simplified stochastic system. Overall, this work introduces an interpretable reinforcement learning simulation tool intended to support comparative evaluation of adaptive versus static strategies in antimicrobial pressure management under limited observability. Full article

Microorganisms can aggregate and organise into structured communities embedded within an exopolysaccharide-based matrsix, which serves as a protective barrier and a functional environment around microbial cells. The formation of biofilms is widely recognised as a pivotal factor in bacterial virulence, impeding the efficacy of antimicrobial agents and hindering immune responses, whilst concomitantly contributing to the development of antimicrobial resistance and the onset of persistent infections. Biofilm formation is a tightly regulated and dynamic process, controlled by quorum-sensing mechanisms and profoundly influenced by environmental factors and nutrient availability. The objective of this review is to elucidate the significance of biofilms in clinical settings, with a particular focus on their role in the pathogenesis of infectious diseases. Particular attention is devoted to biofilm-associated infections and infections related to invasive medical devices, with a particular emphasis on the most prevalent microbial pathogens, which include S. aureus, S. epidermidis, P. aeruginosa, E. coli, K. pneumoniae, A. baumannii and various species of Candida. Furthermore, the present review encompasses biofilm-associated chronic infections, conditions manifesting in predisposed patients, including individuals affected by cystic fibrosis. This review further examines the most recent strategies for combating antibiotic resistance in bacterial biofilms. This review focuses on recent biofilm pathogenesis advancements, with a focus on diagnosis challenges and the need for new ways to disrupt biofilm integrity. Full article

Background/Objectives: Silver’s ability to kill pathogenic bacteria is being widely researched in environment, consumer, and health-related applications. One topic of voluminous research is the antimicrobial properties of silver and silver in wound dressings. This research literature has been reviewed in articles using qualitative analyses, meta-analyses, systematic reviews, bibliometric analyses, and other grounded methods. We present a new strategy for the analysis of the population of articles on the subject based on an ontology of this topic. Methods: A search of the Scopus database for all peer-reviewed articles on silver in wound dressings yielded a population of 4711 relevant ones. The ontology is a logical deconstruction of the problem: “use of silver species on nanosupports deposited on a matrix with antimicrobial effectiveness assayed by methods to promote wound healing of chronic wounds as determined by recovery”. Each bolded term denotes a dimension of the ontology, and each dimension denotes a taxonomy of constituent elements. A Convolutional Neural Network (CNN) was trained using a manually mapped subset of articles. The CNN was then used to map the population of articles. Results: Out of the 4711 articles, 3079 dealt with silver and wound dressings; the others involved silver, but were not related to wound dressings and were not considered. Overall analysis shows that three classes of silver encompass the entire field: silver nanoparticles (AgNP) (78% of papers), inorganic silver-ion-containing species (7%) and silver associated with organic molecules (15%). AgNP papers have grown exponentially beginning in the early 2000s; there is no clear trend regarding inorganic silver-containing-species papers; whereas with the silver-organics species papers, there has been growth in the past decades, but now the number of publications is stabilizing. Research on the AgNPs has primarily focused on in vitro testing (54%), with very limited animal testing (17%) and human testing (3%). On the other hand, with silver-organics, animal (30%) and human testing (38%) are prominent. Inorganic silver ion species also have been human-tested extensively (43%). Thus, in clinical applications of silver wound dressings, AgNP lags considerably as compared to the other silver species, though academic research in AgNP is robust. Conclusions: From detailed temporal visualizations of the ontological mapping, the antecedents and consequences of silver in wound dressings are presented. This first ontological analysis is a novel way of visualizing an entire research field and the temporal characteristics of the various dimensions of the ontology provide information on the current state of research as well as where the field is headed. Full article

Mesenchymal stromal cells (MSCs) have shown immunomodulatory effects and great promise in many inflammatory diseases such as acute respiratory distress syndrome (ARDS). However, several barriers to translation remain such as cell availability and potency. This study evaluates the therapeutic potentials of three types of MSCs, bone marrow-derived MSCs (BM-MSC), the human induced pluripotent stem cell-derived MSC wild type (iMSC WT) and β2 microglobulin-knockout iMSCs (iMSC B2M KO) with or without proinflammatory cytokine preconditioning. BM-MSC, iMSC WT and iMSC B2M KO were preconditioned with a proinflammatory cytokine cocktail (Cytomix: IL-1β, IFN-γ and TNF-α). Immunoregulatory biomarkers were analysed by flow cytometry and cytokines released by ELISA. MSC antimicrobial properties were analysed via CFU assays while the MSCs’ immunomodulatory effects were evaluated using macrophage activation and T cell proliferation assays. Proinflammatory cytokine preconditioning enhanced the therapeutic potency of all three types of MSCs by increasing immunomodulatory marker expression, enhancing the antimicrobial effects and improving MSC-mediated inhibition of T cell proliferation. These findings provided new insights into the therapeutic potencies of MSCs in inflammation. Further studies are required for in vitro characterisation of the MSCs and in vivo efficacy verification of these MSCs prior to their clinical application. Full article

Introduction: Type 2 diabetes mellitus predisposes patients to neuropathy, peripheral arterial disease, and diabetic foot ulcers, which may become infected and progress to osteomyelitis, increasing the risk of amputation. The growing prevalence of multidrug-resistant organisms complicates management. Photodynamic therapy (PDT), which combines a photosensitizer with light-emitting diode irradiation to generate reactive oxygen species, has emerged as a potential adjunctive antimicrobial strategy without inducing resistance. Objective: To describe clinical outcomes observed in patients with diabetic foot osteomyelitis treated with adjunctive photodynamic therapy (PDT), with emphasis on wound evolution, limb preservation, and healing time. Methods: This prospective case series included patients with osteomyelitis secondary to infected diabetic foot ulcers treated at a university hospital. Demographic and clinical data were collected from medical records. Serial photographic documentation was used to monitor wound progression and tissue response during therapy. Results: Sixteen patients with diabetic foot osteomyelitis were included. Complete healing was achieved in 13 patients (81.25%), while 2 patients (12.5%) remained under treatment with partial healing and 1 (6.25%) underwent major amputation. Among healed patients, healing time ranged from 19 to 546 days, with a median of 118 days. The number of photodynamic therapy sessions ranged from 2 to 12, depending on the clinical course of each case. Healing time varied among patients, and the hallux was the most frequent site of osteomyelitis. During follow-up, only one patient underwent major amputation, whereas the remaining patients either achieved complete healing or were still under treatment at the time of analysis. Healing time was comparable between insulin-dependent and non-insulin-dependent diabetes, although numerically shorter in the latter. Longer healing periods were associated with more treatment sessions. Conclusions: In this prospective uncontrolled case series, adjunctive PDT was associated with favorable clinical evolution in a subset of patients with diabetic foot osteomyelitis. However, because of the small sample size and the absence of a control group, these findings should be considered preliminary and hypothesis-generating. Full article

Zinc oxide promotes poultry growth, but it tends to agglomerate. This necessitates high doses and leads to environmental contamination from unabsorbed, excreted zinc. Undigested zinc is excreted and can enter the food chain, increasing the probability of zinc residues in edible poultry tissues (muscle, liver, and eggs) and raising concerns for consumer safety. MOF-supported single-atom zinc catalysts (SAC) resolve agglomeration by atomic anchoring, enhancing bioavailability. High-temperature/high-pressure fixation of Zn²⁺ surfaces was confirmed by XRD, while FESEM revealed the corresponding surface morphology, collectively verifying SAC formation. SAC exhibited potent antimicrobial efficacy against key pathogens such as Salmonella typhimurium, Escherichia coli, and Staphylococcus aureus (MIC of 3.125 mg/mL, MBC of 25 mg/mL). Co-culture experiments further demonstrated that the antibacterial performance of SAC remained stable over a temperature range of 20–80 °C and a pH range of 2–8, thus exhibiting excellent thermal stability and gastrointestinal tolerance. In 7-day-old chicks, SAC alleviated S. typhimurium-induced inflammation, reduced bacterial adherence, upregulated claudin-1, preserved gut homeostasis, ameliorated tissue lesions, and increased the abundance of Lactobacillus in the cecum, demonstrating promising potential for poultry infection control. Full article

Background/Objectives: The prevalence of resistant pathogens in livestock and the environment threatens human health. Frequently used antibiotics in livestock gradually increase the resistance pattern, which intimately threatens the livestock industry. Methods: About 536 pathological samples were collected from January 2023 to December 2024 from chicken (472), birds (2), goat (25), sheep (12), and cows (21) and buffaloes (4), across the Sindh, Pakistan. A wide variety and number of bacterial pathogens were isolated and identified. After performing their antibiogram study, phylogenetic analysis was also performed. Results: The prevalence of different bacterial infections was studied in livestock. Salmonella spp. was found to be the most common cause of bacterial infection in livestock (77.79%), followed by Escherichia coli (62.69%) and Staphylococcus aureus (8.02%). The highest number of Salmonella spp. and S. aureus isolates were found to be resistant to ampicillin (80.67% and 81.4%, respectively), while E. coli isolates were found to be resistant to amoxicillin (97.87%) majorly. MARI revealed that 79.7% of Salmonella spp., including all MDR strains (n = 332); 55.59% of E. coli (n = 336), and 88.37% of S. aureus (n = 43) had indexes greater than 0.2. 16S bacterial identification and phylogenic analysis were performed through molecular methods. Conclusions: AMR is one of the most considerable livestock health issues that also affect human health. The MARI indicate a high rate of antibiotic use and resistance in the isolated Salmonella, E. coli, and S. aureus require the urgent need for continuous antimicrobial susceptibility surveillance and control of antibiotic use in livestock. Full article

The essential oil (EO) of Sideritis L. has attracted great interest due to its pharmacological activities. At the same time, there is significant variability within the type, related, among other things, to the origin of the raw material. The aim of this work was to study the EO chemical composition of Sideritis scardica Griseb. from Bulgaria and Türkiye. The plant material (air-dried above-ground parts) was purchased from herbal and medical stores in Lublin, Poland. The crushed raw material was used for distillation of the EO. Distillation was performed in a Clevenger apparatus. The EO content was expressed in ml per 100 g of air-dried herb. Analysis of the qualitative and quantitative composition of the obtained EO was performed using gas chromatography coupled with a mass spectrometer (450-GC + 240-MS). The antimicrobial activity of the S. scardica EO was evaluated using the broth microdilution method in accordance with the guidelines of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. We have demonstrated that the chemical composition and biological activity of sideritis EO depend on the origin of the raw material. Our results indicate that S. scardica EO can be considered a promising antimicrobial agent. Full article

The growing interest in clean-label and naturally preserved foods has pushed the scientific community to research essential oils (EOs) as sustainable, multifunctional alternatives to chemical preservatives. These plant volatile compounds exhibit strong antimicrobial and antioxidant activities, making them promising ingredients for natural preservation. Fermented meat products, though highly nutritional, are particularly at risk of microbial spoilage and contamination by foodborne pathogens due to their complex microbiota and processing conditions. This review examines the role of EOs as natural antimicrobials in fermented meat systems, summarizing their mechanisms of action, efficiency against key pathogens, and impact on safety, shelf life, and sensory attributes. Additionally, it discusses technological challenges related to volatility, stability, and sensory alterations, and outlines mitigation strategies such as encapsulation, nanoemulsions, and controlled-release delivery systems. By critically presenting current progress and identifying research gaps such as standardization and matrix interactions, this review contributes to the development of effective, natural, and clean-label preservation strategies. These insights support innovation and sustainability in the meat processing industry by bridging the gap between antimicrobial efficacy and sensory acceptability. Full article

When in contact with microbes or other pathogens plants develop an induced defense response. This reaction is triggered by pathogen-derived molecules that provoke the so-called microbe-associated molecular pattern (MAMP)-triggered immunity (MTI) or pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI). Recognition of a MAMP or PAMP by a pattern recognition receptor (PRR) activates rapid downstream signaling, manifested in, e.g., a rise in the cytosolic Ca²⁺ concentration. As a consequence, defense-related genes are expressed and antimicrobial substances are produced. There is also evidence that Ca²⁺-induced responses show a refractory behavior in plant cells, as the reaction to an identical stimulus applied shortly after the first one is strongly suppressed, if it can be observed at all. Subsequent elicitations over a longer period of time, on the other hand, can trigger stronger Ca²⁺ responses, which lead to so-called “defense priming”. Although refractory behavior has been documented in various plant cell types, its underlying function and causative mechanisms remain unclear. In this review article we give an overview of the refractory machinery, including elicitors, receptors, typical Ca²⁺ responses, and signal transduction pathways. We shed light on possible explanatory scenarios and address open questions. Full article