Search Results (3,479)

Calcium silicate-based sealers are widely used in contemporary endodontics, but their strong interaction with dentinal substrates may complicate their removal during nonsurgical retreatment and potentially hinder canal disinfection. This ex vivo study evaluated the effectiveness of different irrigation activation techniques in removing a calcium silicate-based sealer from oval-shaped root canals. Sixty extracted single-rooted teeth were instrumented and obturated using the single-cone technique with NeoSealer Flo, followed by retreatment using a reciprocating system. Specimens were randomly assigned to four final irrigation protocols: conventional needle irrigation (CNI) with NaOCl/EDTA, ultrasonic activation (US), diode laser activation (LI), and Er:YAG laser activation using the SWEEPS mode (SW) (n = 15). Residual filling material was quantified before and after final irrigation using stereomicroscopic imaging and ImageJ (version 1.54) analysis. Dentinal surface morphology and residual sealer were further evaluated using SEM–EDS. Statistical analysis included one-way ANOVA and chi-square tests (p < 0.05). All protocols significantly reduced residual filling material compared with mechanical retreatment alone (US 15.08%, CNI 7.89%, LI 8.01%, SW 7.20%) (p < 0.01). US resulted in significantly greater sealer removal compared with CNI, LI, and SW, with mean differences ranging from 7.08% to 7.88% (p < 0.05). These findings indicate that irrigation activation enhances the removal of NeoSealer Flo calcium silicate-based sealer, with ultrasonic activation demonstrating greater effectiveness among the evaluated techniques, under the conditions of this experimental setup. Full article

(1) Background: University food service establishments are complex environments, where high turnover and handling practices create conditions for microbial persistence. Food-contact surfaces (FCSs) and handlers’ hands (FHs) function as dynamic reservoirs, facilitating the circulation of contaminants within these institutional settings. This study aimed to characterise the microbiological contamination of FCSs and FHs in university food service establishments in Northern Portugal and to evaluate their role as interconnected environmental reservoirs within the indoor built environment. (2) Methods: A total of 590 samples were analysed from two universities in Northern Portugal (L1, L2), comprising 380 FCS and 210 FH samples. Aerobic colony counts (ACCs), Enterobacteriaceae, and Moulds and yeasts (MYs) were analysed according to ISO methods. FH samples were additionally screened for Escherichia coli and Staphylococcus spp. (3) Results: Overall, 35.5% of FCSs were classified as non-compliant, according to microbial criteria based on guideline values from the National Health Institute Dr. Ricardo-Jorge (INSA), with non-compliance primarily driven by elevated ACCs and MYs. Based on a Generalised Linear Model (GLM), establishment types (canteens vs. cafes) were associated with Enterobacteriaceae levels (p = 0.016), whereas ACCs and MYs were not significantly associated with district, establishment type, or functional surface category (p > 0.05). Differences between left and right hands showed small effect sizes, and location was a highly significant determinant of hand hygiene acceptability. (4) Conclusions: FCSs and FHs act as relevant contamination reservoirs in these settings. The results indicate that Enterobacteriaceae levels on FCSs differed between establishment types, while ACCs and MYs showed no significant variation across the evaluated environmental factors. Marked differences in hand hygiene acceptability between campuses support the implementation of targeted interventions, including the optimisation of cleaning and disinfection protocols, the structured training of food handlers, and the routine microbiological monitoring of surfaces and hands to improve institutional food safety. Full article

Increasing water demand and the rising complexity of wastewater matrices, driven by pharmaceuticals, personal care products, and recalcitrant industrial contaminants, require advanced catalytic solutions capable of efficient mineralization under sustainable conditions. Solar-driven processes have attracted growing attention; however, ultraviolet disinfection, heterogeneous photocatalysis, and photo-Fenton systems are commonly treated as independent approaches without mechanistic integration. This review presents a unified photonic–thermal catalytic framework for solar-driven wastewater treatment, emphasizing the interplay between photon absorption, charge-carrier separation, reactive oxygen species generation, and radical-mediated oxidation pathways. The contributions of ultraviolet, visible, and infrared radiation are analyzed in terms of catalyst activation, persulfate and ozone activation mechanisms, and temperature-enhanced reaction kinetics governed by Arrhenius behavior. Particular attention is given to photothermal effects that modulate surface reaction rates, mass transfer, and catalyst stability. By integrating mechanistic insights with reactor-level considerations, this work provides a rational basis for the design of robust solar catalytic systems with enhanced activity, selectivity, and scalability for real wastewater applications. Full article

Candida parapsilosis is a major cause of healthcare-associated infections due to its persistence on abiotic surfaces and efficient transmission via healthcare workers’ hands. This study evaluated the antifungal efficacy and safety of clinically relevant antiseptics against 60 C. parapsilosis clinical isolates using a surface carrier test designed to simulate contamination and disinfection events on hospital surfaces. Antifungal activity was assessed by logarithmic reduction (log₁₀) assays on surface carriers and by minimum inhibitory concentration (MIC) testing. Potential synergistic interactions between antiseptics and selected phytochemicals were investigated using checkerboard assays, and toxicity was evaluated in vivo using Caenorhabditis elegans. Surface carrier assays showed that 70% ethanol and 0.5% alcoholic chlorhexidine (CHG) achieved the highest fungicidal activity, with reductions of up to 5 log₁₀ after 1 min exposure at 25 °C. Polyhexamethylene guanidine hydrochloride (PHMGH) displayed consistently low MIC values (0.4–0.9 ppm) and intermediate surface activity. CHG combined with eugenol or menthol produced strong synergistic interactions, reducing CHG MICs from up to 6250 ppm to as low as 20 ppm (>300-fold). Toxicity assays revealed a narrow safety margin for CHG, whereas PHMGH showed a more gradual concentration-dependent toxicity profile. These findings highlight clinically relevant differences in antiseptic performance and identify combination strategies that may reduce CHG exposure while maintaining antifungal efficacy. Full article

Electrochemical chlorine production is of considerable industrial importance in areas such as water treatment, chemical manufacturing, and disinfection. However, conventional precious metal-based dimensionally stable anodes (DSAs), such as RuO₂- and IrO₂-based systems, are limited by high cost and resource constraints, motivating the development of low-cost alternative catalysts. In this study, Mn₃O₄ electrodes with controllable defect characteristics were fabricated by electrochemical deposition under various processing conditions. The effects of defect modulation and surface modification on the structural, electronic, and electrochemical properties of the electrodes were systematically evaluated. X-ray diffraction analysis confirmed that all deposited films retained a stable tetragonal Mn₃O₄ crystal structure, indicating that the deposition parameters primarily influenced defect states rather than the bulk phase. Mott–Schottky measurements revealed that the Mn₃O₄ electrodes exhibited p-type semiconducting behavior, with charge carrier densities on the order of 10¹⁴ cm⁻³, suggesting that oxygen vacancy-related defect states may contribute to the observed electronic properties of the electrodes. To further enhance anodic performance, Pt was introduced onto the Mn₃O₄ surface via sputtering, resulting in significantly improved charge transfer characteristics. Electrochemical measurements demonstrated that the best performing Pt/Mn₃O₄ electrodes delivered a current density exceeding 100 mA cm⁻² at an applied potential of 1.5 V versus Ag/AgCl. More importantly, defect-enriched Pt/Mn₃O₄ electrodes exhibited markedly enhanced chlorine evolution activity, with the chlorine production rate increasing from approximately 14 µmol cm⁻² to 29 µmol cm⁻², corresponding to an enhancement of about 2.07-fold. Faradaic efficiency analysis further showed that sample (g) and sample (n) achieved chlorine evolution efficiencies of 59.2% and 74.6%, respectively, indicating a higher tendency toward chlorine evolution for the Pt-modified electrodes under the tested conditions. These findings suggest that the synergistic combination of defect engineering and surface modification effectively modulates the electronic structure of Mn₃O₄, providing a viable strategy for improving chlorine evolution performance. Full article

Organ preservation is a necessary and diverse process in morphological studies and is traditionally achieved through formalin fixation and plastination. A comparatively innovative method is organ embedding in epoxy resin, which provides durable and non-toxic models during manipulation. This study aimed to create 30 models: 12 from human specimens and 18 from animal specimens. Samples were incubated in 96.2% ethanol for 24 h to disinfect and remove formalin and excess fat, followed by 100% glycerol incubation for 2 h under vacuum to create a protective interface between the tissue and the activated epoxy resin. Afterward, the tissues were fixed in scaffolds and embedded in epoxy resin. Once hardened, the models were post-processed to enhance clarity and longevity. Each model was mounted on a wooden platform featuring a QR code linking to a presentation describing the visible anatomical structures. Some modifications were made to previously described protocols to optimize the method, improving quality and reducing preparation time. Among the 30 models, two anatomical and two clinical cases of organ preservation were especially interesting. Despite the numerous challenges and limitations, this method yields promising potential for morphological studies, allowing safe organ manipulation without protective equipment and anatomical documentation via QR code-linked presentations. Full article

Climate change presents a challenge for global viticulture due to rising temperatures and water stress, which accelerate grape ripening, increase sugar levels, and reduce acidity. This compromises wine quality and microbial stability, resulting in higher reliance on sulfur dioxide (SO₂). However, SO₂ can inhibit desirable fermentations, including those carried out by non-Saccharomyces yeasts, which are key biotechnological tools for climate adaptation due to their ability to modulate acidity, aroma, and ethanol. Therefore, alternative disinfection methods are needed to control wild microbiota without hindering inoculated yeasts. This review critically analyzes ozone (O₃) as a non-thermal disinfection technology for winemaking. It examines the antimicrobial mechanism of ozone, its efficacy against wine-related microorganisms, its impact on the physicochemical and aromatic parameters of grapes, and its practical viability. Ozone effectively reduces spoilage-causing microbiota, achieving inactivation of approximately 3–4 log CFU/mL for yeasts, while preserving crucial grape compounds and providing a favorable environment for novel fermentation biotechnologies. Compared to other emerging technologies and SO₂, ozone offers a balanced profile: effective disinfection, minimal residues, cost-effectiveness, and compatibility with sustainable winemaking. Ozone is emerging as a promising alternative to facilitate controlled fermentations and improve wine quality among the current climatic and oenological challenges. Full article

Glaesserella parasuis (formerly Haemophilus parasuis, HPS), Actinobacillus pleuropneumoniae (APP), Streptococcus suis (SS), and Pasteurella multocida (PM) are common bacterial pathogens associated with Porcine Respiratory Disease Complex (PRDC), a major cause of economic losses in the swine industry. To address this, a cross-sectional study was conducted across 27 large-scale swine farms in Xinjiang, China (October 2024–May 2025). A total of 1239 clinical samples were analyzed by species-specific PCR, and positive samples were further serotyped. Overall, SS and HPS were the predominant pathogens, with higher detection rates in winter and spring. Notably, SS and HPS were most frequent in nasal swabs, while APP and PM predominated in tissue samples. Furthermore, co-infections were common, with HPS + SS being the most prevalent. Serotyping revealed dominance of HPS serotype 12, APP serotype 12, SS serotype 3, and PM serotypes A and B (serotypes E and F not detected). In addition, SS was also detected in environmental samples and farm workers’ nasal swabs. These findings suggest that future prevention and control strategies should focus on developing multivalent vaccines targeting the predominant serotypes identified, implementing regular serotype surveillance to guide precision immunization protocols, and strengthening environmental disinfection and biosecurity practices to reduce co-infections and occupational exposure risks. Full article

Zeolitic imidazolate framework-8 (ZIF-8) is one of the most extensively studied metal–organic frameworks due to its high surface area, tunable porosity, chemical stability, and intrinsic antimicrobial activity. Recent research has focused on engineering ZIF-8 through metal doping and surface functionalization to enhance its physicochemical performance and expand its applications in food safety and environmental systems. Metal-doped ZIF-8 incorporating Cu²⁺, Fe²⁺/Fe³⁺, Ag⁺, or Mn²⁺ improves reactive oxygen species generation, enables controlled metal-ion release, and promotes synergistic bactericidal mechanisms against both Gram-positive and Gram-negative pathogens. In parallel, surface modification using biopolymers such as hyaluronic acid, chitosan, alginate, and polyethylene glycol enhances colloidal stability, reduces cytotoxicity, modulates surface charge, and improves adhesion to food-contact surfaces, thereby enhancing coating stability and sustained antimicrobial activity. These combined strategies support the development of multifunctional nanoplatforms with improved dispersibility, controlled release behavior, and compatibility with food packaging, sanitization, and water treatment applications. From a sustainability perspective, ZIF-8-based systems offer the potential to reduce reliance on conventional chemical disinfectants, minimize chemical residues, and enable the integration of biodegradable polymer matrices for safer and more environmentally responsible antimicrobial solutions. This review summarizes recent advances in synthesis strategies, structure–property relationships, antimicrobial and antibiofilm mechanisms, and environmental safety considerations. Key challenges, including scalability, regulatory acceptance, stability, and long-term ecotoxicological impact, are discussed, along with perspectives on stimuli-responsive systems, essential oil encapsulation, and smart antimicrobial coatings. Full article

Inspired by their biocompatibility and thermoreversible gelation—transitioning from room temperature liquids to body temperature gels—Pluronic hydrogels were employed in this study to optimize intracanal penetration and ensure medicament stability. We developed a silver nanoparticle (AgNP)-loaded Pluronic gel (AgNPs-P-gel) as a biocompatible, easily removable intracanal medicament. Following PRILE 2021 guidelines, AgNPs-P-gels (F127/F68) were evaluated for gelation, AgNP release, and antibacterial activity against Enterococcus faecalis and Streptococcus mutans via minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and growth curves. Biofilms in bovine teeth were quantified using CFUs and scanning electron microscope (SEM) imaging. Biocompatibility was tested in L-929 fibroblasts using MTT assays and RT-qPCR for pro-inflammatory cytokines (IL-6, TNF-α, IL-1β). Removal efficacy from bovine canals was microscopically scored. The optimized formulation (20% F127, 7.5% F68) gelled at 34 °C with sustained release over 168 h. AgNPs-P-gel showed strong antibacterial activity (MIC: 25–50 µg/mL). In ex vivo models, 100 µg/mL AgNPs-P-gel (AgNPs-100-P-gel) reduced bacterial counts comparably to calcium hydroxide and chlorhexidine, but with lower cytotoxicity. Although inducing cytokine expression similar to conventional medicaments, AgNPs-P-gel demonstrated significantly superior removability. Thermoreversible AgNPs-P-gel offers sustained antimicrobial action, favorable biocompatibility, and superior removability, potentially improving endodontic disinfection predictability as a calcium hydroxide alternative. Full article

Acinetobacter baumannii is a leading cause of healthcare-associated infections and is classified among the highest-priority antimicrobial-resistant pathogens. Its clinical success reflects the convergence of antimicrobial resistance (AMR) and biological traits that promote environmental persistence and transmission. Acinetobacter baumannii has undergone a remarkable transformation over the past few decades, evolving from a relatively obscure environmental bacterium into a globally recognized multidrug-resistant pathogen. Its prevalence in healthcare settings, particularly intensive care units, has made it a leading cause of ventilator-associated pneumonia, bloodstream infections, wound infections, and urinary tract infections. Beyond its antibiotic resistance, the bacterium’s ability to persist in hospital environments and adapt to host defences has amplified its clinical significance. Recent research has uncovered complex networks of virulence factors, regulatory systems, and metabolic strategies that enable A. baumannii to thrive in hostile environments and evade host immunity, providing new insights into its pathogenesis and potential therapeutic vulnerabilities. This review summarizes the main mechanisms underlying its pathogenicity, including desiccation tolerance, biofilm formation, disinfectant resistance, metal acquisition, motility, and the ability to enter viable but non-culturable states. In A. baumannii, AMR functions as a pathogenesis-adjacent trait, enhancing survival and clonal dissemination through genomic plasticity, resistance islands, efflux systems, and envelope remodeling. Key resistance pathways involve carbapenem-hydrolyzing oxacillinases, metallo-β-lactamases, permeability defects, and multidrug efflux, often coexisting within high-risk clones. From a clinical perspective, management of carbapenem-resistant strains requires accurate infection diagnosis, reliable susceptibility testing, site-specific and PK/PD-optimized therapy, and early reassessment. Overall, the success of A. baumannii reflects the integration of resistance and persistence within healthcare ecosystems, highlighting the need for coordinated strategies combining stewardship, infection control, improved diagnostics, and anti-biofilm or anti-virulence approaches. Full article

Background: Reusable tourniquets are widely used across clinical settings, yet their role as reservoirs of microbial contamination and antimicrobial resistance remains poorly characterized. Methods: In this cross-sectional study, 53 polyester–elastane tourniquets were collected from an Emergency Department (SR) and Operating Theater (SBO) over a 28-day period to assess bacterial burden and resistome composition. A 180-target qPCR panel targeting antibiotic and disinfectant resistance determinants was used. qPCR analysis identified 112 distinct resistance genes across all samples, with SR tourniquets harboring significantly richer resistomes than SBO (median 34 vs. 15 genes; p < 0.001). Efflux pump- and disinfectant-associated genes were pervasive, and β-lactamase and quinolone-resistance determinants increased over time in SR samples. Results: Principal component analysis showed clear segregation of resistome profiles by clinical unit and progressive enrichment over time. These findings indicate that reusable, porous tourniquets can accumulate extensive resistance gene profiles under routine clinical use, particularly in high-contact environments. Conclusions: Enhanced decontamination strategies, development of new materials or transition to single-use alternatives may be necessary to mitigate their potential contribution to environmental antimicrobial resistance in hospitals. Full article

The study aimed to evaluate the effect of chlorhexidine (CHX), chlorin p6-mediated photodynamic therapy (PDT), magnesium oxide nanoparticles (MgONPs), and Clp6-functionalized MgONPs on smear layer removal and shear bond strength of a two-step etch-and-rinse adhesive to caries-affected dentin. Seventy-five human permanent molars with occlusal carious lesions and ICDAS scores of four and five were included. Twenty-five samples were used to prepare dentin discs 2 mm in thickness. The remaining samples, along with 25 discs, were arbitrarily allocated into five disinfectant groups, with n = 15 per group (10 teeth and 5 discs). Group I: Control, Group II: 2% CHX, Group III: Clp6-mediated PDT, Group IV: MgONPs, and Group V: Clp6-functionalized MgONPs. SL removal assessment, nanoparticle characterization, and EDX were performed using SEM. Fifty CAD were etched, followed by fifth-generation adhesive application and composite build-up. SBS and failure modes were evaluated with a universal testing machine and stereomicroscope, respectively. Group 4 (MgONPs) specimens displayed the maximum cleaning of SL (1.11 ± 0.13) and the highest SBS (10.32 ± 0.18 MPa). However, minimum SL removal (2.87 ± 0.94) and bond strength (7.42 ± 0.25 MPa) were exhibited by Group 1 (No disinfectant) samples. MgONPs possess the potential to be used as a cavity disinfectant, as they efficiently remove SL from CAD and augment the bond integrity outcomes. Full article

Background: Additively manufactured surgical guides require post-processing and subsequent decontamination prior to intraoral use. Steam sterilization and chemical disinfection protocols may influence the dimensional stability of polymer-based guide materials and potentially affect clinical fit and accuracy. Objectives: This in vitro study evaluated the dimensional changes of SLA 3D-printed Surgical Guide Resin V1 (Formlabs) after steam sterilization at 121 °C (AUT121) and 134 °C (AUT134) and after disinfection using 70% isopropyl alcohol (IPA70), compared with an untreated control group. Methods: Forty standardized specimens were fabricated using SLA technology and divided into four groups (n = 10/group): Control (CT), 121 °C steam sterilization (AUT121), 134 °C steam sterilization (AUT134), and IPA70 disinfection. Two linear measurement zones (L1 and L2) were assessed per specimen. Baseline measurements were recorded with a caliper (mm). Post-treatment measurements were obtained using microscopic evaluation, recorded in µm, and converted to mm for analysis. Dimensional change was calculated as ΔL = L_after − L_before. Within-group comparisons and between-group analyses were performed with a significance level of α = 0.05. Results: Steam sterilization at 134 °C (AUT 134) produced statistically significant dimensional changes in both zones (L1: p = 0.036; L2: p = 0.042). No statistically significant differences were observed in the AUT121 group (L1: p = 0.437; L2: p = 0.682) or the IPA70 group (L1: p = 0.164; L2: p = 0.086). Between-group analysis showed no significant differences for ΔL1 (p = 0.345), whereas ΔL2 differed significantly among groups (p = 0.021). Conclusions: Under the conditions of this study, AUT134 steam sterilization significantly affected the dimensional stability of SLA-printed Surgical Guide Resin V1 specimens. The AUT121 protocol and IPA70 disinfection did not result in statistically significant dimensional changes compared with baseline. Full article

We evaluated the indoor environmental quality of the administrative office at University Medical Center Ho Chi Minh City branch 2 and implemented a multi-stage engineering control strategy to optimize occupational health conditions. A cross-sectional assessment monitored important air quality parameters, including carbon dioxide (CO₂), fine particulate matter (PM2.5 and PM10), humidity, and illumination. Following baseline measurements, an integrated system was deployed to address pollutant mass balance, consisting of High-Efficiency Particulate Air (HEPA) filtration units for mechanical particle scrubbing, ceiling-mounted axial fans to induce forced convection, and ultraviolet-C germicidal lamps for photochemical disinfection. Post-intervention results demonstrated significant gains in system removal efficiency. CO₂ concentrations decreased by over 60% due to enhanced volumetric air exchange, while PM2.5 levels decreased by more than 40% through interception and diffusion mechanisms within the HEPA media. Furthermore, UVC irradiation achieved a 90% reduction in viable airborne microbial colonies. The results of this study show that low-cost, scalable environmental engineering controls and fluid dynamic optimizations effectively mitigate indoor air pollution and enhance workplace stability in healthcare administrative settings. Full article