Search Results (10,118)

This in vitro study compared the antimicrobial and antibiofilm efficacy of four commercially available chlorhexidine (CHX)-based mouthwashes, with different nominal CHX concentrations, against clinically relevant postoperative oral pathogens, including Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Antimicrobial potency was evaluated using MIC and CEMIC indices, while biofilm thickness reduction was quantified using 3D digital microscopy and custom image analysis software. Among the tested formulations, the excipient-enriched formulation exhibited the lowest MIC values and the most significant reduction in biofilm thickness, particularly against Gram-negative bacteria and Candida species. All mouthwashes achieved CEMIC < 0.1, confirming high theoretical applicability margins; however, CEMIC reflects potential clinical usefulness rather than clinical superiority. The findings demonstrate that the antimicrobial and antibiofilm activity of CHX rinses is formulation-dependent and cannot be predicted solely by CHX concentration. The influence of excipients is discussed as a possible contributing factor, but related mechanisms remain speculative and require direct validation in future studies. This work supports a formulation-driven, evidence-based approach to antiseptic comparison in postoperative dentistry, without assessing clinical wound-healing outcomes. Full article

Infective endocarditis (IE) due to methicillin-susceptible Staphylococcus aureus (MSSA) still represents a clinical and therapeutic issue. Discrepancies between guidelines, clinical studies and clinical practice have already been highlighted, especially regarding daptomycin use in MSSA cases. The aim of this study was to evaluate daptomycin’s impact on outcomes in this setting. This was a retrospective observational study. We enrolled all patients with MSSA IE admitted from 2015 to 2023. Patients were divided into two groups according to daptomycin administration. We enrolled 76 patients, with 49 in group A (standard treatment) and 27 in group B (treated with daptomycin). The in-hospital crude mortality was 14.3% and 29.6% in group A and B, respectively (p = 0.191). Only heart failure was significantly associated with negative outcome in the univariate and multivariate analyses (OR 6.424, 95% CI, 1.680–24.559; p = 0.007). In this study population, daptomycin treatment for IE due to MSSA was not associated with a reduced mortality rate. Heart failure was the only independent risk factor associated with in-hospital mortality. Full article

Field-effect transistor (FET) biosensors enable label-free and real-time electrical transduction; however, their practical deployment is often constrained by the need for bulky benchtop instrumentation to provide stable biasing, low-noise readout, and data processing. Here, we report a portable extended-gate FET (EG-FET) integrated sensing system that consolidates the sensing interface, analog front-end conditioning, embedded acquisition/control, and user-side visualization into an end-to-end prototype suitable for on-site operation. The system couples a screen-printed Au extended-gate electrode to a MOSFET and employs a low-noise signal-conditioning chain with microcontroller-based digitization and real-time data streaming to a host graphical interface. As a proof-of-concept, enterohemorrhagic Escherichia coli O157:H7 was selected as the target. A bacteria-specific immunosensing interface was constructed on the Au extended gate via covalent immobilization of monoclonal antibodies. Measurements in buffered samples produced concentration-dependent current responses, and a linear calibration was experimentally validated over 10⁴–10¹⁰ CFU/mL. In specificity evaluation against three common foodborne pathogens (Staphylococcus aureus, Salmonella typhimurium, and Listeria monocytogenes), the sensor showed a maximum interference response of only 13% relative to the target signal (ΔI/ΔImax) with statistical significance (p < 0.001). Our work establishes a practical hardware–software architecture that mitigates reliance on benchtop instruments and provides a scalable route toward portable EG-FET sensing for rapid, point-of-need detection of foodborne pathogens and other biomarkers. Full article

Cannabidiol (CBD), the primary bioactive element of cannabis, has shown promise in alleviating pain and inflammation, although mechanisms in periodontal inflammation are not fully understood. To improve its limited solubility and mucosal permeability, the developed chitosan-based mucoadhesive hydrogel incorporating CBD-loaded PLGA nanospheres (CPN hydrogel) was characterized by FT-IR, SEM, particle size, rheological, swelling, and diffusion analyses, followed by biological evaluations, including wound-healing and RT-qPCR-based anti-inflammatory assays. The improved CPN hydrogel had a homogeneous shape, better viscoelastic behavior, and sustained drug release. Over 90% of CBD was released within 96 h, and Franz cell experiments showed improved permeability (124.1 μg/cm² after 72 h). The gellan gum-based mucosal substrate significantly increased adhesion (1137.33 ± 142.25 s) compared to the control groups. Antioxidant studies indicated 73.65% DPPH radical scavenging, whereas antibacterial tests showed more than 99% suppression of Staphylococcus aureus. Furthermore, in vitro studies validated its wound healing and the downregulation of the inflammatory cytokines IL-6 and TNF-α. The results indicate that the CPN-loaded chitosan hydrogel has extended mucosal retention, strong antibacterial activity, and steady release of CBD. This underscores its significant potential as a targeted treatment for inflammatory oral diseases such as gingivitis and periodontitis. Full article

The escalating threat of antibiotic resistance, particularly from Staphylococcus aureus (S. aureus), has become a critical challenge in both public health and animal husbandry. The extensive use of conventional antibiotics in livestock production accelerates the emergence of resistant strains, heightening risks to food safety and human health. Although plant-derived bioactive compounds are increasingly recognized as promising alternatives to synthetic antimicrobials, the mechanisms underlying their efficacy—and the potential for synergistic action among different plant parts—remain poorly understood. In particular, the antibacterial interactions among extracts from different tissues of Cyperus esculentus L. (C. esculentus), a plant rich in flavonoids and phenolics, have yet to be systematically evaluated. Here, we investigated the antibacterial properties and mechanisms of ethanol extracts from the tubers, stems–leaves and their mixture of C. esculentus against S. aureus. Using Oxford cup diffusion assays, scanning electron microscopy (SEM), bacterial growth kinetics, and untargeted metabolomics, we assessed both phenotypic inhibition and metabolic disruption. The mixed extract exhibited the strongest antibacterial effect, producing a 26.15 mm inhibition zone—approximately 7% greater than that of single-part extracts—and induced cell wall rupture and disintegration as observed by SEM. Growth curve analyses revealed time-dependent bacterial suppression, while metabolomic profiling identified 845 differential metabolites, indicating disturbances in amino acid, lipid, and nucleotide metabolism. Flavonoids such as acacetin, diosmetin, naringenin, and silybin A were identified as principal active compounds contributing to these effects. Full article

Bacterial infections and the lack of bioactivity of titanium implants and their alloys remain critical challenges for the long-term performance and clinical success of these devices. These issues arise from the undesirable combination of early microbial adhesion and the limited ability of metallic surfaces to form a bioactive interface capable of supporting osseointegration. To address these limitations simultaneously, this study employed electrical discharge machining (EDM), which enables surface topography modification and in situ incorporation of bioactive ions from the dielectric fluid. Ti-6Al-4V ELI surfaces were modified using two dielectric fluids, a fluorine/phosphorus-based solution (DF1-F) and a calcium/phosphorus-based solution (DF2-Ca), under positive and negative polarities. The recast layer was characterized by SEM and EDS, while bioactivity was evaluated through immersion in simulated body fluid (SBF) for up to 21 days. Antibacterial performance was assessed against Staphylococcus aureus at 6 h and 24 h of incubation. The results demonstrated that dielectric composition and polarity strongly influenced ionic incorporation and the structural stability of the modified layers. The DF2-Ca(+) condition exhibited the most favorable bioactive response, with Ca/P ratios closer to hydroxyapatite and surface morphologies typical of mineralized coatings. In antibacterial assays, Ca/P-containing surfaces significantly decreased S. aureus attachment (>80–90%). Overall, EDM with Ca/P-containing dielectrics enables the fabrication of Ti-6Al-4V surfaces with enhanced mineralization capacity and anti-adhesive effects against Gram-positive bacteria, reinforcing their potential for multifunctional biomedical applications. Full article

The pistachio nut (Pistacia vera L.) is a rich and high-quality source of protein, as is its waste. This study investigated the potentials of pistachio nut waste proteins to obtain bioactive peptides exhibiting antioxidative and antibacterial activities, and their amino acid profile. Enzymatic hydrolysis with pepsin, trypsin, chymotrypsin, and savinase was applied to the pistachio protein isolate (PPI) obtained from pistachio waste. In addition, solid-state fermentation (SSF) was applied to defatted pistachio with Bacillus subtilis, and peptides were produced. The highest degree of hydrolysis was obtained at 28.2% by using pepsin (p < 0.05). The highest ABTS radical scavenging activity was found as 232 µmol TE/g defatted pistachio (d.b.) for trypsin hydrolysate (p < 0.05). The maximum DPPH radical scavenging activity was found as 70.2 µmol TE/g defatted pistachio (d.b.) by hydrolysis with savinase. After gel filtration, the highest ABTS radical scavenging activity was found to be 0.1166 mg TE/mL in the T7 sample (p < 0.05), while the highest DPPH scavenging activity was found to be 0.0573 mg TE/mL in the S8 sample (p < 0.05). The sample showing the highest antibacterial activity was chymotrypsin hydrolysate with MIC = 0.378 mg/mL against Staphylococcus aureus. The total amino acid contents (TAA) of PPI, hydrolysate samples, and the SSF sample ranged from 63.136 to 76.665 g/100 g protein. It was also seen that proteins and peptides obtained from pistachio waste have a rich amino acid profile, especially Asp and Tyr, and good antioxidant activity. Full article

Clinical data on antimicrobial profiles are useful for dairy udder health treatment programmes and represents a component of antimicrobial stewardship. The study aimed to determine the bacterial aetiology of clinical mastitis in dairy herds in Western Australia and to evaluate their antibiotic resistance profiles. This retrospective study utilised clinical antimicrobial profile data from two referral diagnostic centres within the region of Western Australia. A total of 545 mastitic samples were submitted for antimicrobial culture and testing over a period of 10 years (2008–2018). Of these, 406 showed bacterial growth and 139 no bacterial growth was observed. The most common isolates were Streptococcus uberis (25.3%), Staphylococcus aureus (17.2%), and Escherichia coli (9.4%). No growth was identified in 25.5% of the mastitis milk samples. The antimicrobial profiles revealed high susceptibilities towards cefuroxime (95.7%), clavulox (89.4%), and oxytetracycline (89%), whilst showing high resistance towards novobiovin (70%). From this study, it is concluded that there was a decline in the resistance trends towards the isolates of both S. uberis and S. aureus over the 10-year period and contagious mastitis had a higher occurrence. There is a need to consider surveillance programmes that determine the patterns of on-farm antimicrobial usage and further characterise the pathogens based on the presence of resistance antimicrobial genes. Data on antimicrobial surveillance represent an important component of antimicrobial stewardship. Full article

Objective: The emergence and spread of multi-drug-resistant (MDR) bacteria pose a growing threat in veterinary medicine, particularly in equine hospitals. This study investigated the colonization and infection dynamics of horses undergoing emergency laparotomy with two distinct antibiotic protocols (single-shot versus 5-day protocol) during hospitalization. Methods: Nasal swabs and fecal samples were collected from 67 horses undergoing emergency laparotomy at clinic admission as well as on postoperative days 3 and 10. These were screened for multi-drug-resistant indicator pathogens. As multi-drug-resistant indicator pathogens, methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-E), and bacteria belonging to the Acinetobacter baumannii complex were defined. Results: Preoperatively, 6.2% of horses tested positive for MRSA and 13% for ESBL-E. An increase in colonization was observed on day 3 postoperatively, with 62.1% of nasal swabs and 86.4% of fecal samples testing positive for MDR organisms. On day 10, 53.4% of nasal swabs and 62.5% of fecal samples tested positive for indicator pathogens. Surgical site infection developed in five horses, two of which tested positive for MRSA in both nasal and wound samples during hospitalization, supporting the potential role of nasal carriage as a source of infection. Furthermore, all horses tested positive for ESBL-E during at least one time-point during hospitalization, and Enterobacterales (MDR in two surgical site infections (SSI)) were involved in all surgical site infections. No significant differences were observed between the two antibiotic treatment groups regarding colonization rates with indicator pathogens during hospitalization. However, the results indicate that hospitalization itself contributes to increased colonization with resistant bacteria. A clear limitation of the study is the restricted number of sampled horses and the lack of environmental contamination data. Non-sampled hospitalized horses with and without antibiotic treatment may have acted as reservoirs for MDR bacteria. Conclusion: The findings emphasize the need for routine environmental monitoring and strict adherence to hygiene protocols in equine clinics to reduce the risk of nosocomial transmission. Ongoing surveillance and infection control strategies are essential to mitigate the spread of MDR pathogens in veterinary settings. Full article

Biofilms formed by Staphylococcus aureus on medical devices and tissue surfaces are a major contributor to persistent infections due to their resistance to antibiotics. Hydrodynamic forces in physiological and device-associated environments significantly influence biofilm development, yet the dynamics of detachment and regrowth under flow remain poorly quantified. In this study, biofilm surface coverage was measured in microfluidic flow assays across combinations of shear rates and nutrient concentrations. A computational workflow was used to segment biofilm trajectories into three kinetic phases—growth, exodus, and regrowth—based on surface coverage dynamics. Each phase was modeled using parametric functions, and fitted parameters were interpolated across experimental conditions to reconstruct biofilm lifecycles throughout the flow–nutrient conditions. The analysis revealed that intermediate shear rates triggered early detachment events while suppressing subsequent regrowth, whereas lower and higher shear regimes favored biofilm persistence. The resulting model enables quantitative comparison of condition-specific biofilm behaviors and identifies key thresholds in mechanical and nutritional inputs that modulate biofilm stability. These findings establish a phase-resolved framework for studying S. aureus biofilms under hydrodynamic stress and support future development of targeted strategies to control biofilm progression in clinical and engineered systems. Full article

Three new pyrrole alkaloids, streptopyrroles D–F (1–3), along with four known analogs (4–7) were isolated from Sea Anemone-Associated Streptomyces sp. S1502 via an OSMAC (One Strain Many Compounds)-based strategy. Their structures were elucidated through comprehensive spectroscopic analyses, including HRESIMS and 1D/2D NMR experiments (COSY, HSQC, and HMBC), and further confirmed by X-ray crystallography. Biological evaluation identified streptopyrrole (4) as an anti-MRSA (methicillin-resistant Staphylococcus aureus) agent, while 4 and 6 displayed broad-spectrum cytotoxicity and good selectivity against a panel of human cancer cell lines. Notably, 4 and 6 showed particularly potent activity against the lung cancer cell lines H1299, SW1573, and A549, with IC₅₀ values ranging from 5.43 to 16.24 μM. Further mechanistic investigation revealed that both compounds suppress the proliferation of lung cancer cells by inducing cell cycle arrest at the G₀/G₁ phase and impair metastatic potential by inhibiting migration and invasion. These findings not only expand the structural diversity of marine-derived pyrrole alkaloids but also reveal the anticancer mechanisms of 4 and 6, highlighting their promise as active candidates for further antitumor drug development, particularly in lung cancer. Full article

Background/Objectives: Syndromic multiplex PCR assays such as BIOFIRE FilmArray^® Pneumonia (PN) panel enable rapid and simultaneous detection of bacterial and viral pathogens in respiratory specimens, improving diagnostic accuracy and patient management in lower respiratory tract infections (LRTIs). Methods: In this retrospective observational study, PN panel results in 410 bronchoalveolar lavage (BAL) samples from hospitalized patients with suspected pneumonia were analyzed and compared with those obtained using the conventional culture (CC) method. Results: The PN panel showed an overall positivity rate of 54%, detecting bacteria in 39.0% of samples, viruses in 7.1%, and atypical bacteria in 2.2%. Using the conventional culture (CC) method, 33.9% of samples tested positive. Overall, 83 (20.2%) samples that were positive by the PN panel were negative by CC, whereas only 14 specimens (3.4%) were positive by CC and negative by PN panel. The most frequently detected pathogen by both the PN panel and CC was Staphylococcus aureus (n = 67, 16.34% for PN; n = 40, 9.76% for CC). Regarding diagnostic performance, the PN panel demonstrated a sensitivity of 89.02%, a specificity of 97.86%, and an overall accuracy of 97.63%. Lower sensitivity values were observed only for the Enterobacter cloacae complex (57.14%) and the Klebsiella pneumoniae group (75%). Specificity exceeded 92% for all bacterial targets. Conclusions: The PN panel confirms enhanced pathogen detection and a shortened time-to-result. It serves as a valuable adjunct for the timely diagnosis of LRTIs, supporting antimicrobial stewardship through more precise and appropriate antibiotic selection. Full article

This study investigates the synthesis of silver nanoparticles (AgNPs) using Crassula ovata (Jade plant) leaf extract and their subsequent incorporation into chitosan-based nanocomposite films for enhanced antimicrobial activity against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Methicillin-resistant Staphylococcus aureus. Jade AgNPs were chosen for their ease of synthesis, stability, and potent antimicrobial activity. Chitosan encapsulation improved the stability of AgNPs and enhanced their interaction with bacterial cells, leading to improved bactericidal performance. The addition of gentamicin to the nanocomposite further amplified antibacterial activity, reducing the MBC values from 10 to 4 µg/mL for E. coli, 12.5 to 6 µg/mL for P. aeruginosa, 10 to 6 µg/mL for S. epidermidis, and 15 to 8 µg/mL for MRSA, compared to AgNPs alone. Mechanical characterization using dynamic mechanical analysis revealed improved robustness, with storage modulus increasing from approximately 24 MPa for chitosan-AgNPs films to 36 MPa for gentamicin-loaded nanocomposite films, while maintaining elasticity. Overall, these multifunctional nanocomposite films demonstrate strong antimicrobial activity and improved mechanical performance, supporting further evaluation as candidate materials for wound-related antimicrobial applications and localized infection control strategies. Such localized antimicrobial platforms may also contribute to strategies aimed at mitigating antibiotic resistance. Full article

The threat of antimicrobial resistance (AMR) and the need for sustainable disinfectants have spurred interest in natural antimicrobials such as essential oils (EOs). However, their application is limited by volatility, poor water solubility, and cytotoxicity. Herein, we present the development of bio-based core–shell sub-micro-/nanocapsules (NCs) with encapsulated oregano (OO), thyme (TO), eucalyptus (EuO), and tea tree (TTO) oils to enhance antimicrobial (AM) performance and reduce cytotoxicity. NCs were synthesized via a nanoencapsulation method using chemically modified zein or poly(methyl vinyl ether-co-maleic anhydride) (GZA) as shell polymers, with selected EOs encapsulated in their core (encapsulation efficacy > 98%). Chemical modification of zein with vanillin (VA) and GZA with either dodecyl amine (DDA) or 3-(glycidyloxypropyl)trimethoxysilane (EPTMS) resulted in improvement in particle size distributions, polydispersity indices (PDIs) of synthesized NCs, and in the stability of the NC-dispersions in water. Antibacterial testing against Staphylococcus aureus and cytotoxicity assays showed that encapsulation significantly reduced toxicity while preserving their antibacterial activity. Among the formulations, GZA-based NCs modified with EPTMS provided the best balance between safety and efficacy. Despite this, life cycle assessment revealed that zein-based NCs were more environmentally sustainable due to lower energy use and material impact. Overall, the approach offers a promising strategy for developing sustainable, effective, and safe EO-based antibacterial agents for AM applications. Full article

Background/Objectives: Topical application of isosorbide diesters (IDEAS) derived from coconut and sunflower seed oil improve atopic dermatitis (AD) and reduce topical steroid use in adults. This randomized, double-blind, vehicle-controlled trial evaluates topical IDEAS (isosorbide diesters) with colloidal oatmeal for pediatric AD. Methods: Subjects aged 2–17 with mild to moderate AD applied either colloidal oatmeal cream or colloidal oatmeal cream with IDEAS daily. Hydrocortisone 2.5% was used as needed. AD severity, itch, sleep, steroid use, and microbiome data were collected at baseline, week 4, and week 8. Results: More participants in the IDEAS group compared to the control group achieved EASI 50 (81.0% vs. 56.3%, p = 0.10) and EASI 75 (42.9% vs. 18.8%, p = 0.12) and achieved a 4-point reduction in subjective itch at week 4 (45.5% vs. 6.3%, p = 0.0085) and week 8 (42.9% vs. 12.5%, p = 0.045). Use of topical steroids was lower in the IDEAS group (3.4 g vs. 13.3 g, p = 0.012) and the relative abundance of Staphylococcus aureus was reduced after 8 weeks. Conclusions: The addition of IDEAS to colloidal lotion improved AD, improved itch, reduced the use of topical steroids, and reduced the relative abundance of S. aureus in the skin microbiome. Full article