Search Results (10,486)

Background/Objectives: Dental caries is one of the most prevalent chronic diseases in childhood, disproportionately affecting socially vulnerable populations. This scoping review aimed to analyze the clinical effects of selected minimally invasive materials and approaches, specifically mouthrinses, fluoride varnishes, silver diamine fluoride, and glass ionomer-based interventions, for the prevention and management of dental caries in pediatric patients, with emphasis on public health and community-based settings. Methods: This scoping review followed the Population, Concept, and Context (PCC) framework. Electronic searches were conducted up to 23 January 2026, using tailored strategies for mouthrinses, fluoride varnishes, silver diamine fluoride (SDF), and glass ionomer cements (GICs). Randomized clinical trials (RCTs) were included. Data extraction and qualitative synthesis focused on clinical outcomes and applicability in public health contexts. Results: Fifty-five RCTs were included. Fluoride- or chlorhexidine-based mouthrinses showed potential in controlling cariogenic biofilm, with evidence primarily based on microbiological outcomes. Fluoride varnishes were associated with enamel remineralization and control of early white spot lesions, particularly in supervised programs. SDF was reported to achieve high caries’ arrest rates in cavitated dentin lesions of primary teeth, while its preventive effect on sound surfaces appeared comparable to other fluoride-based interventions. GICs were associated with acceptable clinical performance as pit-and-fissure sealants and in atraumatic restorative treatment. Conclusions: Minimally invasive dentistry (MID) approaches show promise for the prevention and management of childhood dental caries in public health and community-based settings. However, these findings should be interpreted with caution due to the heterogeneity of interventions and outcome measures, the predominance of short-term and surrogate (microbiological) outcomes, and the absence of a formal risk-of-bias assessment. As a scoping review, the synthesis is narrative in nature, which limits the ability to draw definitive conclusions. Further studies with standardized clinical outcomes and longer follow-up are needed to strengthen the evidence. Full article

Background: COVID-19 is primarily a respiratory disease, but increasing evidence suggests possible oral and maxillofacial complications. This study presents a case series of post-COVID maxillary osteonecrosis (PC-RONJ) cases from western Romania and explores the possible association between SARS-CoV-2 infection, its treatment, and this complication. Methods: We conducted a multicenter retrospective case series of two patients with recent PCR-confirmed SARS-CoV-2 infection who subsequently developed maxillary osteonecrosis (ONC) between 2021 and 2023. Clinical examination, CT imaging (including 3D reconstructions), and ENT assessment were used to assess the severity of the disease. All medical records were reviewed to identify comorbidities, details of COVID-19 treatment, and the appearance of maxillofacial symptoms. Results: Both patients had been hospitalized for severe COVID-19 and treated according to the national protocol with systemic corticosteroids, oxygen therapy, anticoagulation, and antivirals. CT scans revealed marked osteolytic destruction of the maxilla and maxillary sinus walls, with extension toward adjacent facial bones. Microbiological analysis revealed a complex polymicrobial profile, including Gram-positive and Gram-negative bacteria as well as opportunistic fungal species, consistent with a chronic biofilm-associated infectious process. Patients received surgical treatment, followed by local care and, in both cases, prosthetic rehabilitation with maxillary obturators, which improved speech, chewing, and oral function. Conclusions: This case series suggests a possible association between severe COVID-19, its treatment, and subsequent maxillary osteonecrosis in susceptible patients; however, the small number of cases precludes causal inference. To our knowledge, this is the first Romanian report describing such cases in patients without prior antiresorptive therapy. These findings highlight the need for careful use of systemic corticosteroids and vigilant post-recovery monitoring of maxillofacial complications. Further studies are required to clarify the underlying mechanisms and risk factors. Full article

Background/Objectives: Staphylococcus aureus, particularly methicillin-resistant strains, is a leading cause of severe pneumonia. Understanding local molecular epidemiology, including virulence gene profiles and antimicrobial resistance (AMR) mechanisms, is crucial for effective infection control. This pilot study aimed to characterize S. aureus isolates from pneumonia patients in Karaganda, Kazakhstan. Methods: We collected 48 respiratory samples from patients with pneumonia across three medical institutions. Bacterial identification was performed using MALDI-TOF MS. Antimicrobial susceptibility testing (AST) was carried out using European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Whole-genome sequencing of S. aureus isolates was conducted on an Ion Torrent S5 platform. Genomic analysis included multilocus sequence typing (MLST), identification of virulence and AMR genes, and phylogenetic reconstruction. Results: S. aureus was identified in 14.6% (n = 7) of pneumonia cases included in this study. All isolates (100%, n = 7) were phenotypically resistant to benzylpenicillin. The mecA gene was detected in 57.1% of isolates (n = 4), while phenotypic resistance to methicillin was observed in 28.6% (n = 2) of the isolates. Resistance to azithromycin (57.1%, n = 4) and levofloxacin (42.9%, n = 3) was observed among the isolates. Two isolates (28.6%) were multidrug-resistant (MDR). Genomic analysis revealed the prevalence of the ST22 clone (57.1%, n = 4) in the studied cohort. Other sequence types were ST97, ST8, and ST45 (14.3% each). Phylogenetic analysis showed clustering consistent with MLST profiles. All isolates carried a conserved core virulence arsenal, including hemolysin (hla, hlg), biofilm-forming genes (icaADBC), immune evasion genes (sak, scn), and iron acquisition genes (isd). The Panton–Valentine leukocidin (PVL) genes were detected in three isolates. AMR gene analysis revealed the ubiquitous presence of mepA and tetracycline efflux pump genes, along with regulatory genes (arlRS, mepR, mgrA). The blaZ and ermA genes were not detected despite high phenotypic resistance to penicillin and macrolides. Conclusions: This study reports the identification of the virulent and resistant ST22 S. aureus clone in pneumonia cases in Karaganda, Kazakhstan. The discordance between phenotypic and genotypic AMR profiles underscores the necessity for integrated diagnostic approaches. Full article

Acinetobacter baumannii, a prominent opportunistic pathogen in healthcare settings, causes severe infections and poses significant challenges for clinical treatment. This study investigates the synergistic effects of α-pinene combined with meropenem (MEM) on A. baumannii biofilm formation and lung injury in mice, aiming to develop new strategies to combat persistent infections and antibiotic resistance. α-pinene combined with MEM exhibited strong synergistic antibacterial activity against carbapenem-resistant A. baumannii (CRAB 5E9). The combination significantly inhibited biofilm formation, extracellular polymer production, surface motility, and quorum sensing. The expression of key genes such as ompA, bfmR, bap, csuAB, abaI, and abaR was reduced by up to 61%. In vivo, the treatment alleviated weight loss, decreased the bacterial load in lung tissue, and reduced lung inflammation. Furthermore, it significantly suppressed proteins involved in the inflammatory response and the MAPK pathway, including TLR4, NF-κB, NLRP3, TRAF6, ERK2, p38 MAPK, JNK, and TNF-α. The combination of α-pinene and MEM synergistically inhibits A. baumannii biofilm formation and alleviates the inflammatory response in a mouse model, offering a potential therapeutic approach for combating A. baumannii infections. Full article

Methicillin-resistant Staphylococcus aureus (MRSA) is a major antimicrobial-resistant pathogen affecting both human and animal health. Although historically associated with healthcare settings, MRSA is now established in livestock production and throughout the production chain. Its detection in animals, food products, and processing environments reflects the complex ecology of antimicrobial resistance (AMR) in modern food systems. This narrative review synthesizes current evidence on the molecular basis of methicillin resistance and multidrug resistance determinants, as well as the epidemiology of MRSA in food-associated settings. Particular emphasis is placed on its occurrence in animal-derived foods and key reservoirs within farms, slaughterhouses, and processing environments. Livestock-associated populations are dominated by clonal complex CC398. In contrast, CC9 is prevalent in pig production systems in Asia, while CC5-related lineages occur at the human and animal interface. MRSA has been detected in retail meat and animal-derived foods at low but measurable prevalence, indicating contamination during slaughter and processing. Virulence determinants include staphylococcal enterotoxins linked to food poisoning and Panton–Valentine leukocidin associated with severe infections. Biofilm formation and adhesins further support persistence and colonization. Epidemiological and molecular evidence indicates that livestock, processing environments, and food-contact surfaces act as interconnected reservoirs sustaining MRSA circulation. Human exposure occurs primarily through occupational contact and environmental pathways, whereas foodborne transmission appears less common. Effective control requires integrated surveillance, responsible antimicrobial use in livestock production, and strict hygiene practices throughout the production chain within a One Health framework. Full article

Deammonification, which is based on partial nitritation and anammox (PN/A), is a well-established sidestream treatment for nitrogen removal. However, transferring deammonification to mainstream wastewater treatment remains challenging due to low temperatures, the need to retain slow-growing anammox bacteria (AnAOB), and their competition for nitrite with nitrite-oxidizing bacteria (NOB) and heterotrophic denitrifiers. This work investigates cubic polyurethane foam carriers to promote growth and retention of AnAOB. A moving bed biofilm reactor (MBBR) and an integrated fixed-film activated sludge (IFAS) reactor were compared over a three-year experimental period at lab-scale. The feasibility of the biofilm carriers for deammonification was first evaluated under sidestream conditions, followed by a stepwise transition to mainstream operational conditions. The impact of operational parameters, including dissolved oxygen concentration, pH value, and aeration strategy, was evaluated with respect to the activity of aerobic ammonium-oxidizing bacteria (AOB), NOB, and AnAOB, as well as nitrogen removal rates. Deammonification reached nitrogen removal rates of 0.04–0.12 kg N m⁻³ d⁻¹ (IFAS reactor) and 0.02–0.28 kg N m⁻³ d⁻¹ (MBBR) at subphases with reactor bulk concentrations above 60 mg NH₄-N L⁻¹. Highest nitrogen removal degrees of 77 ± 6% (IFAS) and 76 ± 5% (MBBR) were achieved at reactor bulk concentrations of 96 mg NH₄ L⁻¹ and 97 mg NH₄ L⁻¹, respectively. Lower concentrations triggered NOB activity in both reactors, leading to an increase in nitrate concentration up to 22 mg NO₃-N L⁻¹. AOB and AnAOB activities were on average 6-fold higher on the carriers compared to suspended biomass throughout all experimental phases, demonstrating the feasibility of using cubic polyurethane foam carriers for deammonification. This was also confirmed by fluorescence in-situ hybridization (FISH) measurements. Median nitrogen removal rates over all experimental phases of 0.07 kg N m⁻³ d⁻¹ for the IFAS reactor and 0.05 kg N m⁻³ d⁻¹ for the MBBR were achieved, which are comparable to conventional activated sludge systems performing nitrogen removal via nitrification–denitrification. While at lower nitrogen concentrations, the IFAS reactor yielded superior nitrogen removal rates, peak nitrogen removal rates of 0.28 kg N m⁻³ d⁻¹ were measured in the MBBR configuration. However, controlling NOB activity at lower temperatures and concentrations remains a challenge in MBBR and IFAS configurations. In our study, in the IFAS reactor NOB activities were visible on fewer days than in MBBR. At mainstream-like conditions, higher nitrogen removal rates of IFAS (0.09–0.12 kg N m⁻³ d⁻¹) were achieved compared to the MBBR (0.06–0.09 kg N m⁻³ d⁻¹). This demonstrates the advantage of the IFAS reactor in treating mainstream wastewater via deammonification. As an autotrophic nitrogen removal process, the implementation of deammonification in the mainstream of municipal wastewater treatment plants enables enhanced recovery of biogas from sewage organic matter. The latter would otherwise be consumed during the conventional nitrification-denitrification pathway. Consequently, the overall energy balance for wastewater treatment can be improved, contributing to a more environmentally sustainable process. Full article

Hesperidin, a flavonoid abundantly found in citrus fruits, has demonstrated a substantial role in the management of various pathogeneses. Furthermore, the wide range of health-promoting properties of hesperidin, including antioxidant, anti-inflammatory, anti-cancerous, hepatoprotective, neuroprotective, nephroprotective, and cardioprotective effects, has been well documented. Additionally, persuasive evidence from both in vivo and in vitro studies highlights its substantial roles in combating obesity, protecting the kidneys, liver, and lung tissue architecture, promoting wound healing, and modulating immune responses. This flavonoid acts as an effective antimicrobial agent against a wide range of microorganisms by inhibiting biofilm formation and disrupting the cell membrane. This review aims to deliver comprehensive insights into the therapeutic potential of hesperidin across different pathogenesis through distinct mechanisms. Moreover, it provides up-to-date evidence on the synergistic properties of this compound with other drugs as well as compounds, and emerging plans to enhance its efficiency in health management through various nanoformulation approaches. Despite its considerable therapeutic potential, the clinical application of hesperidin remains constrained by poor bioavailability, rapid degradation, and dosage-related limitations. Addressing these challenges will require extensive further research to clarify its mechanisms of action, safety profile, and therapeutic efficacy in managing underlying pathogenic conditions. Full article

The secretome of ESKAPE pathogens, including Klebsiella pneumoniae, comprises a diverse array of bioactive molecules that govern virulence, antibiotic resistance, and the establishment of an immunosuppressive microenvironment. However, the high chemical complexity of the secretome impedes the identification of key metabolites mediating pathogenesis. In this study, we profiled the metabolite composition of cell-free K. pneumoniae supernatant using a combined approach of chromatographic fractionation and Raman spectroscopy. Chromatographic separation enabled the resolution of the complex secretome and revealed fractions with distinct biochemical signatures. A key finding was the identification of Fraction 3, characterized by a unique metabolic profile: it was enriched in nucleic acid fragments, peptides containing tyrosine and methionine, polysaccharides, and stress-response metabolites (e.g., citrate), while notably lacking markers of tryptophan and sterol-like lipids. These spectral signatures suggest a potential role for Fraction 3 metabolites in intercellular communication, biofilm formation, and protection against oxidative stress. The remaining fractions also exhibited distinct biochemical profiles, defined by unique profiles of lipids, nucleotides, and amino acids. Collectively, these data underscore the critical role of specific K. pneumoniae secreted metabolites to pathogen survival and host immune modulation. The combined approach effectively resolves functionally relevant secretome fractions, offering new avenues for identifying diagnostic and therapeutic targets for multidrug-resistant infections. Full article

Background: Many of the pathogenic bacteria and fungi found in hospital environments form biofilms, which allow them to persist in the environment for long periods, posing a risk of hospital-acquired infections. Although the pathogens within biofilms often have reduced levels of drug susceptibility, the efficacy of disinfectants routinely applied against planktonic pathogens must be evaluated against biofilms as well. Our objective in this study was to determine the efficacy of treatment using slightly acidic hypochlorous acid water and to compare the results with sodium hypochlorite when both were used to disinfect Candida parapsilosis biofilms. Methods: C. parapsilosis in the planktonic or biofilm state was treated with each disinfectant. The number of viable cells that remained was determined, and scanning electron microscopy (SEM) of the disinfectant-treated biofilms was performed. Results: Compared with sodium hypochlorite, in a shorter period of time, hypochlorous acid water completely killed not only planktonic C. parapsilosis but also C. parapsilosis in a biofilm that had been formed for 72 h. SEM showed that both disinfectants were effective in removing the C. parapsilosis biofilm to some extent. Conclusions: Slightly acidic hypochlorous acid water appears to be an effective disinfectant against C. parapsilosis both in suspension and in biofilms. Full article

Vulvovaginal candidiasis (VVC) is a common gynecological infection, with Pichia kudriavzevii emerging as a significant pathogen due to its intrinsic fluconazole resistance and biofilm-forming capacity. This study investigates the antifungal efficacy and mechanisms of tannic acid (TA) against P. kudriavzevii, as well as its potential to reverse azole resistance across multiple Candida species with distinct resistance profiles. TA significantly inhibited P. kudriavzevii growth, surface colonization, and virulence gene expression at 3 μg/mL. Mechanistically, TA protected the human vaginal epithelial cell line VK2/E6E7 by reducing ROS levels, restoring mitochondrial membrane potential, and suppressing IL-1β and IL-18 release through modulation of the NLRP3-Caspase1-ASC axis. Furthermore, TA demonstrated synergistic activity when combined with azoles against five clinically azole-resistant Candida isolates spanning three Candida species with distinct resistance mechanisms: P. kudriavzevii (intrinsic), C. albicans (acquired), and N. glabrata (FKS-mediated). This study highlights TA as a promising natural therapeutic agent for P. kudriavzevii infections and offers a novel strategy for combating multidrug-resistant Candida through combination therapy. Full article

Bacterial persistence, a non-heritable high-antibiotic-tolerance phenotype, is a key driver of recurrent clinical infections and antibiotic treatment failure. The pheromone-responsive pCF10 plasmid in Enterococcus faecalis (E. faecalis) mediates antibiotic resistance gene dissemination, but its role in bacterial persister formation remains unclear. This study systematically investigated the regulatory role of pheromone cCF10 in the persister phenotype of pCF10-carrying E. faecalis and its underlying molecular mechanisms. We confirmed that cCF10 enhanced persistence against levofloxacin in OG1RF (pCF10), with the persister frequency increasing from 0.291% to 16.466% upon treatment. Transcriptomic analysis revealed that cCF10 activated the (p)ppGpp-mediated stringent response and downregulated the expression of genes associated with energy-intensive pathways, including those involved in DNA repair, protein folding, and respiration. Concurrently, cCF10 enhanced the expression of genes related to biofilm formation and cell lysis resistance and downregulated components of its own sensing and uptake systems. These findings demonstrate that cCF10 induces transcriptional reprogramming associated with increased persister formation in E. faecalis carrying the pCF10 plasmid and identify potential targets within the stringent response and associated metabolic pathways for the development of anti-persister strategies. Full article

Microbial communities inhabiting natural and anthropogenically impacted environments are exposed to diverse abiotic stressors that can influence the distribution of functional traits. However, distinguishing the processes underlying phenotypic patterns remains challenging in microbial systems, where ecological and evolutionary dynamics often overlap. In this study, we experimentally assessed the distribution of biofilm formation and plastic degradation capacity in bacterial isolates across environments characterized by different stress regimes, to evaluate whether these traits are primarily associated with environmental context rather than phylogenetic relatedness, and may therefore reflect environment-dependent phenotypic modulation on a lineage-specific functional background. Taxonomic affiliation was assessed using 16S rRNA gene sequencing, while expressed biochemical profiles were characterized by Fourier-transform infrared (FTIR) spectroscopy. Multivariate ordination and Partial Least Squares analyses were used to explore relationships among taxonomy, biochemical profiles, functional phenotypes, and environment of isolation. Phylogenetic signal analysis confirmed that neither trait was strongly constrained by vertical inheritance, with Blomberg’s K ≈ 0 and Fritz & Purvis’ D = 0.51, consistent with environment-driven rather than phylogenetically conserved trait distributions. Both biofilm production and plastic degradation capacity showed significant environment-dependent differences in their relative frequencies (Fisher’s exact test, biofilm: p = 5.5 × 10⁻⁵; PCL degradation: p = 2.5 × 10⁻⁴) and were not directly associated with each other (Wilcoxon rank-sum test, p = 0.45; linear model, p = 0.68). Overall, these results indicate that microbial functional traits are unevenly distributed across environments and weakly constrained by taxonomy, consistent with the contribution of multiple, non-mutually exclusive processes that remain difficult to disentangle empirically. Full article

Carbapenem-resistant Acinetobacter baumannii (CRAB) is classified as a critical priority pathogen by the World Health Organization, and new therapeutic alternatives are urgently needed. In this study, we performed genomic mining of 27,531 A. baumannii genomes and identified 5144 prophage-derived endolysin candidates. Four highly prevalent candidates (E1–E4) were recombinantly expressed and functionally evaluated against A. baumannii. Among them, E1 exhibited the strongest bactericidal activity against reference strains ATCC 19606 and CMCC 25001, with a minimum inhibitory concentration in the micromolar range. E1 effectively disrupted preformed biofilms (>60% reduction) and remained stable under a broad range of temperatures (4–60 °C), pH values (6–8), and NaCl concentrations (up to 500 mM). Structural analysis indicated that E1 adopts a canonical lysozyme-like fold with key residues for peptidoglycan binding, and its lytic activity in vitro relied on 1 mM EDTA-mediated outer membrane permeabilization. In a murine peritoneal infection model, combination therapy with E1 and meropenem (each at 1 × MIC) significantly increased the survival rate to 66.7% and reduced bacterial loads in blood and multiple organs. This study demonstrates that prophage-derived endolysin E1 acts synergistically with meropenem against A. baumannii, supporting E1 as a promising candidate for developing combination therapies against CRAB. Full article

Salmonella enterica remains a major threat to animal and human health because of its broad host range, increasing antimicrobial resistance (AMR), and capacity to form biofilms. Biofilm formation enhances bacterial persistence in host tissues, farm environments, food-processing systems, and clinical reservoirs, while also contributing to their tolerance against antibiotics, disinfectants, and other stresses. However, biofilm capacity is not uniform across serovars and is influenced by host adaptation, niche specialization, and accessory genome content. This review synthesizes current knowledge on the relationship between biofilm formation, AMR, and serovar-specific adaptation in Salmonella. It examines biofilm-associated traits across various hosts (e.g., gastrointestinal tract and gallbladder, and environmental (e.g., food-production and clinical) niches, and discusses comparative evidence from genomic, transcriptomic, proteomic, and metabolomic studies. Particular attention is given to the emerging concept of comparative biofilmomics, which integrates phenotypic and multi-omics data across diverse serovars and host sources to identify conserved and niche-specific determinants of persistence. This framework may help define high-risk lineages that couple multidrug resistance (MDR) with enhanced biofilm-forming capacity. A better understanding of these linked traits will support the development of more targeted interventions for controlling persistent Salmonella in veterinary, food production, and public health settings. Full article

Methicillin-resistant Staphylococcus aureus (MRSA) is a major clinical problem due to its resistance, virulence, and biofilm formation, which diminish antibiotic efficacy. This review explores natural products and antimicrobial nanoparticles (NPs) as alternative and combined strategies for controlling MRSA. Natural compounds, such as plant metabolites, essential oils, antimicrobial peptides, and fungal products, act by disrupting membranes, interfering with cellular processes, and limiting biofilm formation. Antimicrobial NPs, especially metal and metal oxide materials, act through membrane damage, oxidative stress, and metal ion release, enabling activity against resistant bacteria and improving biofilm penetration. Combining natural products with NPs increases stability, delivery, and local activity, enhances antibacterial effects, and reduces effective doses. Green synthesis enables direct integration of bioactive compounds, while nano-delivery platforms optimize solubility and controlled release. Nanotechnology-based applications such as wound dressings, nanocarriers, and multifunctional platforms support localized and sustained treatment and promote tissue repair. Despite these advances, clinical use is still constrained by safety concerns, variability in NP properties, and the lack of standardized evaluation and regulatory frameworks. Overall, combining natural products with antimicrobial NPs offers a practical strategy to augment MRSA treatment, but further progress depends on consistent design, robust safety evaluation, and clinical translation. Full article