Search Results (902)

This review explores the biofilm architecture and drug resistance of Enterococcus faecalis in clinical and environmental settings. The biofilm in E. faecalis is a heterogeneous, three-dimensional, mushroom-like or multilayered structure, characteristically forming diplococci or short chains interspersed with water channels for nutrient exchange and waste removal. Exopolysaccharides, proteins, lipids, and extracellular DNA create a protective matrix. Persister cells within the biofilm contribute to antibiotic resistance and survival. The heterogeneous architecture of the E. faecalis biofilm contains both dense clusters and loosely packed regions that vary in thickness, ranging from 10 to 100 µm, depending on the environmental conditions. The pathogenicity of the E. faecalis biofilm is mediated through complex interactions between genes and virulence factors such as DNA release, cytolysin, pili, secreted antigen A, and microbial surface components that recognize adhesive matrix molecules, often involving a key protein called enterococcal surface protein (Esp). Clinically, it is implicated in a range of nosocomial infections, including urinary tract infections, endocarditis, and surgical wound infections. The biofilm serves as a nidus for bacterial dissemination and as a reservoir for antimicrobial resistance. The effectiveness of first-line antibiotics (ampicillin, vancomycin, and aminoglycosides) is diminished due to reduced penetration, altered metabolism, increased tolerance, and intrinsic and acquired resistance. Alternative strategies for biofilm disruption, such as combination therapy (ampicillin with aminoglycosides), as well as newer approaches, including antimicrobial peptides, quorum-sensing inhibitors, and biofilm-disrupting agents (DNase or dispersin B), are also being explored to improve treatment outcomes. Environmentally, E. faecalis biofilms contribute to contamination in water systems, food production facilities, and healthcare environments. They persist in harsh conditions, facilitating the spread of multidrug-resistant strains and increasing the risk of transmission to humans and animals. Therefore, understanding the biofilm architecture and drug resistance is essential for developing effective strategies to mitigate their clinical and environmental impact. Full article

Background/Objectives: This study evaluated the in vitro probiotic potential of Lactiplantibacillus plantarum Probio87 (Probio87), focusing on its physiological robustness, safety, antimicrobial properties, and anticancer activity, with relevance to vaginal and cervical health. Methods: Tests included acid and bile salt tolerance, mucin adhesion, and carbohydrate utilization. Prebiotic preferences were assessed using FOS, GOS, and inulin. Antibiotic susceptibility was evaluated per EFSA standards. Antimicrobial activity of the cell-free supernatant (CFS) was tested against Staphylococcus aureus, Escherichia coli, and Candida species. Effects on Lactobacillus iners and L. crispatus were analyzed. Anticancer properties were assessed in HeLa, CaSki (HPV-positive), and C-33A (HPV-negative) cervical cancer cell lines through proliferation, apoptosis, angiogenesis, and cell cycle assays. Results: Probio87 showed strong acid and bile tolerance, efficient mucin adhesion, and broad carbohydrate utilization, favoring short-chain prebiotics like FOS and GOS over inulin. It met EFSA antibiotic safety standards. The CFS exhibited potent antimicrobial activity, including complete inhibition of Candida albicans. Probio87 selectively inhibited L. iners without affecting L. crispatus, indicating positive modulation of vaginal microbiota. In cervical cancer cells, the CFS significantly reduced proliferation and angiogenesis markers (p < 0.05), and induced apoptosis and cell cycle arrest in HPV-positive cells, with minimal effects on HPV-negative C-33A cells. Conclusions: Probio87 demonstrates strong probiotic potential, with safe, selective antimicrobial and anticancer effects. Its ability to modulate key microbial and cancer-related pathways supports its application in functional foods or therapeutic strategies for vaginal and cervical health. Full article

The aim of this work is to evaluate the effectiveness of antimicrobial photodynamic therapy (aPDT) against oral MDR (multi-drug-resistant) Candida spp. infections related to orthodontic treatment with palatal expanders through in vitro study. Methods: PDT protocol: Curcumin + H₂O₂ was used as a photosensitizer activated by a 460 nm diode LED lamp, with an 8 mm blunt tip for 2 min in each spot of interest. In vitro simulation: A palatal expander sterile device was inserted into a custom-designed orthodontic bioreactor, realized with 10 mL of Sabouraud dextrose broth plus 10% human saliva and infected with an MDR C. albicans clinical isolate CA95 strain to reproduce an oral palatal expander infection. After 48 h of incubation at 37 °C, the device was treated with the PDT protocol. Two samples before and 5 min after the PDT process were taken and used to contaminate a Petri dish with a Sabouraud field to evaluate Candida spp. CFUs (colony-forming units). Results: A nearly 99% reduction in C. albicans colonies in the palatal expander biofilm was found after PDT. Conclusion: The data showed the effectiveness of using aPDT to treat palatal infection; however, specific patient oral micro-environment reproduction (Ph values, salivary flow, mucosal adhesion of photosensitizer) must be further analyzed. Full article

Nosocomial infections caused by ESKAPE pathogens represent a significant burden to global health. These pathogens may exhibit multidrug resistance (MDR) mechanisms, of which mechanisms such as efflux pumps and biofilm formation are gaining significant importance. Multidrug resistance mechanisms in ESKAPE pathogens have led to an increase in the effective costs in health care and a higher risk of mortality in hospitalized patients. These pathogens utilize antimicrobial efflux pump mechanisms and bacterial biofilm-forming capabilities to escape the bactericidal action of antimicrobials. ESKAPE bacteria forming colonies demonstrate increased expression of efflux pump-encoding genes. Efflux pumps not only expel antimicrobial agents but also contribute to biofilm formation by bacteria through (1) transport of molecules and transcription factors involved in biofilm quorum sensing, (2) bacterial fimbriae structure transport for biofilm adhesion to surfaces, and (3) regulation of a transmembrane gradient to survive the difficult conditions of biofilm microenvironments. The synergistic role of these mechanisms complicates treatment outcomes. Given the mechanistic link between biofilms and efflux pumps, therapeutic strategies should focus on targeting anti-biofilm mechanisms alongside efflux pump inactivation with efflux pump inhibitors. This review explores the molecular interplay between efflux pumps and biofilm formation, emphasizing potential therapeutic strategies such as efflux pump inhibitors (EPIs) and biofilm-targeting agents. Full article

Biofilms, structured communities of microorganisms encased in an extracellular matrix, are a major cause of persistent infections, particularly when formed on medical devices. This study investigated the kinetics of biofilm formation by Escherichia coli and Pseudomonas aeruginosa, two clinically significant pathogens, on two medical-grade polymers: polyether ether ketone (PEEK) and polyamide 12 (PA12). Using a modified crystal violet staining method and spectrophotometric quantification, we evaluated biofilm development over time on polymer granules and catheter segments composed of these materials. Results revealed that PEEK surfaces supported significantly more biofilm formation than PA12, with peak accumulation observed at 24 h for both pathogens. Conversely, PA12 demonstrated reduced bacterial adhesion and lower biofilm biomass, suggesting surface characteristics less conducive to microbial colonization. Additionally, the study validated a reproducible protocol for assessing biofilm formation, providing a foundation for evaluating anti-biofilm strategies. While the assays were performed under static in vitro conditions, the findings highlight the importance of material selection and early prevention strategies in the design of infection-resistant medical devices. This work contributes to the understanding of how surface properties affect microbial adhesion and underscores the critical need for innovative surface modifications or coatings to mitigate biofilm-related healthcare risks. Full article

Burn injuries are complex and require effective wound management strategies. Traditional treatments, such as dermal templates, are limited by simplified extracellular matrix (ECM) composition (e.g., collagen-elastin or collagen-glycosaminoglycan), sheet-based formats, and frequent use of animal-derived materials. These limitations can reduce wound conformity, biocompatibility, and integration with host tissue. Functional hydrogels are being explored as alternatives due to properties such as high water content, biodegradability, adhesiveness, antimicrobial activity, and support for angiogenesis. Unlike standard templates, hydrogels can adapt to irregular wound shapes as in burn wounds and reach deeper tissue layers, supporting moisture retention, cell migration, and controlled drug delivery. These features may improve the wound environment and support healing in burns of varying severity. This review outlines recent developments in functional hydrogel technologies and compares them to current clinical treatments for burn care. Emphasis is placed on the structural and biological features that influence performance, including material composition, bioactivity, and integration capacity. Through an exploration of key mechanisms of action and clinical applications, this review highlights the benefits and challenges associated with hydrogel technology, providing insights into its future role in burn care. Full article

This study involved the fabrication of poly (vinyl alcohol) (PVA) nanocomposite films using the solution-casting process, which incorporated strontium-coated silver oxide (Sr-Ag₂O) nanoparticles generated by a plant-extract assisted method. Various characterization techniques, such as XRD, SEM, TEM, UV, and FTIR, showed the formation and uniform distribution of Sr-Ag₂O nanoparticles in the PVA film, which are biocompatible nanocomposite films. The presence of hydroxyl groups leads to appreciable mixing and interaction between the Sr-Ag₂O nanoparticles and the PVA polymer. Mechanical and thermal results suggest enhanced tensile strength and increased thermal stability. In addition, the sample of PVA/Sr-Ag₂O (1.94/0.06 wt. ratio) nanocomposite film showed decreased hydrophilicity, lower hemolysis, non-toxicity, and appreciable cell migration activity, with nearly 19.95% cell migration compared to the standard drug, and the presence of Sr-Ag₂O nanoparticles favored the adhesion and spreading of cells, which triggered the reduction in the gaps. These research findings suggest that PVA/Sr-Ag₂O nanocomposite films with good mechanical, antimicrobial, non-toxic, and biocompatible properties could be applied in biological wound-healing applications. Full article

Background/Objectives: Listeria monocytogenes is a foodborne pathogen of major public health concern due to its ability to invade host cells and cause severe illness. This study aimed to develop and validate a multi-tiered screening pipeline to identify Bacillus strains with probiotic potential against L. monocytogenes. Methods: A total of 26 Bacillus isolates were screened for antimicrobial activity, gastrointestinal resilience, and host cell adhesion. A fluorescence-based infection assay using mCherry-expressing HCT 116 cells was used to assess cytoprotection against L. monocytogenes NCTC 7973. Eight strains significantly improved host cell viability and were validated by quantification of intracellular CFU. Two top candidates were tested in a murine model of listeriosis. The genome of the lead strain was sequenced to evaluate safety and biosynthetic potential. Results: B. subtilis CECT 8266 completely inhibited intracellular replication of L. monocytogenes in HCT 116 cells, reducing bacterial recovery to undetectable levels. In vivo, it decreased splenic bacterial burden by approximately 6-fold. Genomic analysis revealed eight bacteriocin biosynthetic clusters and silent antibiotic resistance genes within predicted genomic islands, as determined by CARD and Alien Hunter analysis. The strain also demonstrated bile and acid tolerance, as well as strong adhesion to epithelial cells. Conclusions: The proposed pipeline enables efficient identification of probiotic Bacillus strains with intracellular protective activity. B. subtilis CECT 8266 is a promising candidate for translational applications in food safety or health due to its efficacy, resilience, and safety profile. Full article

Urinary tract infections (UTIs) are among the most prevalent bacterial infections in women, with high recurrence rates and growing concerns over antimicrobial resistance. The need for alternative or adjunctive therapies has spurred interest in plant-based treatments, which offer antimicrobial, anti-inflammatory, antioxidant, and immune-modulatory benefits. This review summarizes the mechanisms of action, clinical efficacy, and therapeutic potential of various medicinal plants and natural compounds for preventing and treating UTIs in women. Notable candidates include cranberry, bearberry, pomegranate, green tea, and other phytochemicals with proven anti-adhesive and biofilm-disrupting properties. Evidence from clinical trials and meta-analyses supports the role of cranberry natural products and traditional herbal medicines (THMs) in reducing UTI recurrence, especially when combined with antibiotics. Notably, A-type proanthocyanidins in cranberry and arbutin in bearberry are key bioactive compounds that exhibit potent anti-adhesive and biofilm-disrupting properties, offering promising adjunctive strategies for preventing recurrent urinary tract infections. Additionally, emerging therapies, such as platelet-rich plasma (PRP), show promise in restoring bladder function and reducing infection in women with lower urinary tract dysfunction. Overall, plant-based strategies represent a valuable and well-tolerated complement to conventional therapies and warrant further investigation through high-quality clinical trials to validate their efficacy, safety, and role in personalized UTI management. Full article

Fusobacterium nucleatum and activating mutations in the Kirsten rat sarcoma virus oncogene homolog (KRAS) are increasingly recognized as cooperative drivers of colorectal cancer (CRC). F. nucleatum promotes tumorigenesis via adhesion to epithelial cells, modulation of the immune microenvironment, and delivery of virulence factors, while KRAS mutations—present in 60% of CRC cases—amplify proliferative signaling and inflammatory pathways. Here, we review the molecular interplay by which F. nucleatum enhances KRAS-driven oncogenic cascades and, conversely, how KRAS mutations reshape the tumor niche to favor bacterial colonization. We further discuss the use of KRAS as a prognostic biomarker and explore promising non-antibiotic interventions—such as phage therapy, antimicrobial peptides, and targeted small-molecule inhibitors—aimed at selectively disrupting F. nucleatum colonization and virulence. This integrated perspective on microbial–genetic crosstalk offers novel insights for precision prevention and therapy in CRC. Full article

Sternal bursitis is an underexplored lesion in poultry, often overlooked in microbiological diagnostics. In this study, we characterized 36 Escherichia coli isolates recovered from sternal bursitis in broiler chickens, combining phenotypic antimicrobial susceptibility testing, PCR-based screening, and whole genome sequencing (WGS). The genetic analysis revealed a diverse population spanning 15 sequence types, including ST155, ST201, and ST58. Resistance to tetracycline and ciprofloxacin was common, and several isolates carried genes encoding β-lactamases, including blaTEM-1B. Chromosomal mutations associated with quinolone and fosfomycin resistance (e.g., gyrA p.S83L, glpT_E448K) were also identified. WGS revealed a high number of virulence-associated genes per isolate (58–96), notably those linked to adhesion (fim, ecp clusters), secretion systems (T6SS), and iron acquisition (ent, fep, fes), suggesting strong pathogenic potential. Many isolates harbored virulence markers typical of ExPEC/APEC, such as iss, ompT, and traT, even in the absence of multidrug resistance. Our findings suggest that E. coli from sternal bursitis may act as reservoirs of resistance and virulence traits relevant to animal and public health. This highlights the need for including such lesions in genomic surveillance programs and reinforces the importance of integrated One Health approaches. Full article

Background and Objectives: Cyanoacrylate (CA) tissue adhesives have gained increasing attention as alternatives to sutures in oral surgery and periodontology. The objective of this scoping review is to assess their clinical applications and effectiveness in wound closure and postoperative management. Materials and Methods: The review was conducted following the JBI methodology and PRISMA-ScR guidelines. A comprehensive search was performed in PubMed, Scopus, and Web of Science to identify randomized controlled trials published between 2015 and 2025 evaluating the use of CAs in oral surgery and periodontal procedures. Results: A total of 19 studies were included. Cyanoacrylate adhesives demonstrated comparable or superior outcomes to other wound healing strategies in terms of operative time, postoperative pain reduction, and early wound healing. Their use was particularly beneficial in free gingival grafts and palatal donor site management. However, the findings across studies were not always consistent, and some trials did not report statistically significant differences. The use of long-chain CA formulations is associated with minimal toxicological risk, though these adhesives demonstrate intrinsic hemostatic and antimicrobial effects. Conclusions: Cyanoacrylate tissue adhesives represent a valid alternative to sutures in several dental surgical contexts, especially in procedures involving mucogingival grafts. Further high-quality clinical studies are needed to clarify their long-term outcomes and broaden their indications in dentistry. Full article

Background/Objectives: Personalized 3D-printed (3DP) metallic implants delivery systems are being explored to repair bone fractures, allowing the customization of medical implants that respond to individual patient needs, making it potentially more effective and of greater quality than mass-produced devices. However, challenges associated with postsurgical infections caused by bacterial adhesion remain a clinical issue. To address this, local antibiotic therapies are receiving extensive attention to minimize the risk of implant-related infections. This study investigated the use of amikacin (AMK), a broad-spectrum aminoglycoside antibiotic, incorporated onto 3D-printed 316L stainless steel implants using biodegradable polymer coatings of chitosan and poly lactic-co-glycolic acid (PLGA). Methods: This research examined different approaches to coat 3DP implants with amikacin. Various polymer-based coatings were studied to determine the optimal formulation based on the characteristics and release profile. The optimal formulation was performed on the antibacterial activity studies. Results: AMK-chitosan with PLGA coating implants controlled the rate of drug release for up to one month. The 3DP drug-loaded substrates demonstrated effective, concentration-dependent antibacterial activity against common infective pathogens. AMK-loaded substrates showed antimicrobial effectiveness for one week and inhibited bacteria significantly compared to the uncoated controls. Conclusions: This study demonstrated that 3DP metal surfaces coated with amikacin can provide customizable drug release profiles while effectively inhibiting bacterial growth. These findings highlight the potential of combining 3D printing with localized delivery strategies to prevent implant-associated infections and advance the development of personalized therapies. Full article

Some Vibrio parahaemolyticus strains cause translucent post-larvae disease (Vp_TPD), leading to significant economic losses in shrimp farming. We aimed to identify whether a mixture of natural antimicrobials, AuraAqua (Aq), can protect white-leg shrimp (Penaeus vannamei) against the lethal effects of Vp_TPD and to understand its biological mode of action. Herein, we demonstrate that Aq, an antimicrobial mixture composed of a blend of organic acids, citrus, and olive extracts, suppressed Vp_TPD virulence at sub-inhibitory concentrations and conferred robust protection to shrimp. The minimum inhibitory and bactericidal concentrations against the Vp_TPD isolate were at 0.05% and 0.2%, respectively. At 0.05–0.1%, Aq reduced bacterial growth and downregulated six major virulence genes (vhvp-1, vhvp-2, vhvp-3, pirA_Vp, pirB_Vp, pirAB_Vp), while leaving metabolic ldh expression unaltered. Parallel in vitro assays revealed diminished adhesion of Vp_TPD to primary shrimp gut and hepatopancreas epithelial cells and a ≈50% reduction in infection-induced extracellular H₂O₂, indicating an antioxidant effect. The treatment also triggered a time-dependent surge in extracellular alkaline phosphatase (ALP) activity, consistent with membrane permeabilization. In vivo, a challenge of post-larvae with 10⁴ CFU/mL Vp_TPD resulted in 91% mortality after 45 h; co-treatment with 0.1% and 0.2% Aq reduced mortality to ≈12% and ≈6%, respectively, while 1% Aq achieved ≈98% survival. The clinical protection test confirmed that 0.1% Aq preserved high survival across four pathogen inocula (10¹–10⁴ CFU/mL). Conclusively, Aq destabilized the pathogen and therefore transcriptionally silenced multiple virulence determinants, translating into significant in-pond protection for controlling Vp_TPD for shrimp aquaculture. Full article

Antibiotic overuse has contributed to the emergence of multidrug-resistant (MDR) bacteria, posing a serious public health threat. Pets may act as reservoirs of MDR bacteria, with the potential to transmit these pathogens to humans. This study aimed to identify probiotic alternatives to antibiotics by isolating and evaluating lactic acid bacteria (LAB) from feline milk. In addition to conventional in vitro assessments such as growth kinetics, adhesion ability, safety, and antipathogenic activity, this study also evaluated the antioxidant capacity and production of beneficial metabolites. Three LAB strains were isolated from feline milk, including two strains of Lactobacillus plantarum (M2 and M3) and one strain of Weissella confusa (M1). Resistance assays revealed that strains M2 and M3 exhibited high survival rates under stress conditions, including exposure to bile salts, acidic environments, artificial intestinal and gastric juice. Notably, strain M3 demonstrated strong auto-aggregation ability (73.39%) and high hydrophobicity toward trichloromethane (62.16%). It was also nonhemolytic and susceptible to various β-lactam antibiotics. Furthermore, strain M3 exhibited potent antimicrobial activity in both co-aggregation and Oxford cup assays. Overall, L. plantarum M3 displayed superior probiotic properties, suggesting its potential as an adjunct or alternative to antibiotics in managing MDR bacterial infections in cats. Full article