Search Results (3,181)

Bioactive glass (BAG) S53P4 is a clinically approved bone substitute with antibacterial, osteoconductive and osteostimulatory properties. Its antibacterial effect is associated with ion release, local pH elevation and osmolality, but the precise biochemical and biophysical mode-of-action is unclear. This study investigates the antibacterial mechanism of BAG S53P4 eluates. BAG eluates, collected at 2, 4, 8, and 24 h, eradicated Staphylococcus aureus. Elemental analysis revealed an early increase in concentrations of Si and Na, a later rise in Ca, depletion of P over time and rapid loss of Mg. Membrane disturbances occurred within 5 min, evident by permeability for SYTOX, aligning with time-kill kinetics for S. aureus and Bacillus subtilis. In B. subtilis, 2h-BAG-eluate induced rapid delocalization of marker proteins for cell division and DNA repair, signaling membrane potential collapse and nucleoid condensation. Transcriptomics revealed early transcription remodeling reflecting ionic and energetic imbalance, including disruption of central metabolism, redox homeostasis, and translational stability. Scanning electron microscopy revealed severe cell surface damage and particulate deposits on S. aureus. Transmission electron microscopy showed cell envelop disruptions and cytoplasmic leakage. Energy dispersive X-ray analysis identified Si on bacterial cell surface at 4 h and intracellular accumulation in punctured, empty cells at 24 h. Overall, BAG ionic dissolution products kill bacteria through a stepwise mechanism involving membrane damage, protein delocalization and metabolic impairment, accompanied by Si deposition on bacterial surfaces and loss of Mg. This finally leads to cell wall degradation, cytoplasmic content leakage and further Si deposition on the cells and inside cell ghosts. Full article

Bacterial stem and root rot (BSRR), caused by Dickeya dadantii, poses a severe threat to global sweetpotato production, yet the genetic architecture underlying resistance remains elusive. To dissect these mechanisms, we conducted a high-resolution genome-wide association study (GWAS) on 135 diverse accessions, integrating two-year field phenotyping with best linear unbiased prediction (BLUP) and 6.8 million single-nucleotide polymorphism (SNP) markers. This approach mapped nine quantitative trait loci (QTLs) exhibiting significant allelic dosage-dependent effects, with the major locus, qBSRR.6.1 was the primary discriminator between resistant and susceptible genotypes. Crucially, transcriptomic profiling within these loci revealed distinct expression patterns: IbTCP5 and IbERF003 (located in qBSRR.5.1 and qBSRR.6.2) were highly expressed in the susceptible cultivar ‘Xinxiang’ but suppressed in the resistant ‘Guangshu87’. Furthermore, BSRR challenge identified IbPUB4, IbKCS5, and IbLig1 as priority candidate genes involved in defense, with expression patterns suggesting roles in ubiquitin-mediated protein turnover, cuticular wax biosynthesis, and DNA repair, respectively. In stark contrast, IbPUB25 was constitutively upregulated in ‘Xinxiang’, potentially acting as a negative regulator of immunity via degradation of target proteins. These findings elucidate the polygenic, dosage-sensitive nature of BSRR resistance and prioritize specific targets for future functional characterization. Pyramiding favorable alleles of positive candidates while silencing potential negative regulators like IbPUB25 offers a promising avenue for developing durable, high-resistance sweetpotato varieties. Full article

Modification of PLA with functional nanoparticles is a promising approach for imparting new properties to the material. In this work, titanium nanoparticles (Ti NPs) and titanium dioxide nanoparticles (TiO₂ NPs) were synthesized by laser ablation and characterized by dynamic light scattering, spectrophotometry, and transmission electron microscopy. The average hydrodynamic diameter of Ti NPs was 12 nm, while that of TiO₂ NPs was 24 nm; both dispersions possessed a positive zeta potential (23–27 mV) and spherical morphology. L-PLA composite films containing 0.1 wt.% Ti NPs or TiO₂ NPs were obtained by solution casting. Atomic force and modulation-interference microscopy confirmed the uniform distribution of nanoparticles within the polymer matrix, although partial aggregation was observed. The introduction of TiO₂ NPs increased the water contact angle. Mechanical testing revealed a significant reinforcing effect: the addition of 0.1 wt.% NPs increased the Young’s modulus by 62–68% and the ultimate tensile strength by 16–18% while maintaining a ductile fracture pattern with elongation at break up to ~8%. Both types of composites generated reactive oxygen species (ROS) in aqueous solutions: Ti NPs increased H₂O₂ production by 5.5 times and TiO₂ NPs by 4.9 times, and they also induced the formation of hydroxyl radicals. The accumulation of 8-oxoguanine in DNA and long-lived oxidized protein species confirmed the materials’ ability to cause oxidative damage to biomacromolecules. For E. coli, growth inhibition reached 40.5% (for composites with Ti NPs) and 71% (for composites with TiO₂ NPs). The effect was even more pronounced for S. aureus, where inhibition levels were approximately 70% and 80%, respectively; flow cytometry confirmed the strong bactericidal effect, showing that materials containing TiO₂ NPs increased the proportion of dead cells to 25% for E. coli and ~68% for S. aureus. Cytotoxicity assessment on human fibroblasts (HSF) demonstrated the high biocompatibility of neat L-PLA and composites with Ti NPs (viability > 95%) and with TiO₂ NPs (viability ~93%). The obtained results indicate that L-PLA-based composites with Ti NPs and TiO₂ NPs exhibit pronounced ROS-mediated antibacterial activity without additional UV irradiation. These findings position these materials as highly promising candidates for active biodegradable food packaging to extend shelf-life and for biomedical devices, such as wound dressings and implants, where reducing the risk of bacterial colonization is critical. Full article

Bacillus and Paenibacillus species are common and widely distributed microorganisms in food systems, often implicated in food spoilage and quality issues. Bacillus subtilis, in particular, has been associated with gas production and package bulging in seasoned foods. In this study, we developed a rapid and visual detection method for Bacillus subtilis by integrating (Recombinase Polymerase Amplification) RPA with (Clustered Regularly Interspaced Short Palindromic Repeats) CRISPR/Cas12a technology (designated as RPA-CRISPR/Cas12a). Specific RPA primers and probes were designed based on the conserved gyrB gene of Bacillus subtilis. Two sets of crRNA were designed according to the number of T-rich PAM sites on the RPA-amplified target sequence, and the reaction conditions were optimized in combination with the CRISPR/Cas12a trans-cleavage detection technology. Under optimized conditions, the crRNA3 guide (with a TT-rich PAM site) demonstrated superior cleavage efficiency compared to crRNA2 (TTT-rich PAM), while crRNA1 (TTTT-rich PAM) showed no activity. The assay achieved a detection limit of 150 pg/μL for genomic DNA and 5.5 CFU/mL for bacterial suspensions within 10 min at 37 °C. The method exhibited high specificity and sensitivity, providing a robust tool for early and on-site detection of Bacillus subtilis in food products. Full article

Lung cancer remains the leading cause of cancer-related mortality worldwide, and although immunotherapy has transformed the treatment landscape of advanced non-small cell lung cancer (NSCLC), durable benefit is limited to a subset of patients. PD-L1 immunohistochemistry and tumor mutational burden, while clinically utilized, demonstrate imperfect predictive capacity, underscoring the need for more robust biomarkers. This review highlights emerging multimodal biomarkers—including circulating tumor DNA (ctDNA), the gut microbiome, and artificial intelligence (AI)-driven radiomics—as promising tools to enhance the prediction of immunotherapy response. Longitudinal ctDNA monitoring offers a minimally invasive method to assess tumor burden dynamics, detect early molecular response, distinguish pseudo-progression from true progression, and stratify risk, with ctDNA clearance correlating with improved survival outcomes. The gut microbiome has also been associated with ICI efficacy, as specific bacterial taxa and composite scoring systems correlate with treatment response, though methodological heterogeneity limits clinical translation. Radiomic analyses leveraging CT and PET imaging extract quantitative tumor features that, when integrated with clinical and molecular data, demonstrate improved predictive performance compared to single-modality approaches. Despite promising advances, challenges including assay standardization, external validation, data harmonization, interpretability of AI models, and infrastructure requirements remain barriers to widespread adoption. Multimodal integration of genomic, microbiome, and imaging biomarkers represents a critical step toward precision immuno-oncology, with prospective validation needed to translate these approaches into improved outcomes for patients with advanced NSCLC. Full article

Accurate identification of cariogenic bacteria is crucial for understanding caries development in children. Classical culture methods often underestimate microbial diversity, while polymerase chain reaction (PCR) can detect species that are difficult to cultivate. The aim of this study was to compare culture-based and PCR-based methods for detecting key cariogenic microorganisms in the carious dentin of pediatric patients. Thirty dentin samples were collected from the permanent teeth of children aged 8–14 years. Parallel analyses were performed using standard culture techniques and PCR targeting the gtfB gene of S. mutans and the 16S rRNA gene of Lactobacillus spp. Culture results were quantified as colony-forming units, while PCR results were classified as negative, low-positive, or positive. The results show that culture-based methods identified S. mutans in 16.7% of the samples and Lactobacillus spp. in 3.3%, while PCR identified a signal for S. mutans in 43.3% and Lactobacillus spp. in 100% of the samples. PCR-based methods provide higher sensitivity for detecting key cariogenic bacteria, including S. mutans and Lactobacillus spp. However, PCR detects bacterial DNA and does not indicate bacterial viability or activity. Combining molecular and culture-based approaches allows a more comprehensive assessment of the cariogenic microbiota, supporting accurate microbiological evaluation in pediatric caries research. Full article

Multidrug-resistant Acinetobacter baumannii is a major nosocomial pathogen for which bacteriophages are being explored as alternative antibacterial agents. In this study, we isolated and characterized AUBFM01, a lytic phage active against MDR A. baumannii, and performed an initial assessment of its interaction with PMA-differentiated THP-1 macrophages. AUBFM01 was evaluated by host range testing, adsorption and one-step growth assays, lytic activity, stability testing, biofilm disruption, whole-genome sequencing, and flow cytometry-based macrophage profiling. The phage showed rapid adsorption, a short latent period of approximately 30 min, and a burst size of about 165 phage particles per infected cell. It remained stable under moderate temperature and near-neutral pH conditions and significantly reduced preformed A. baumannii biofilm biomass in vitro. Genomic analysis identified a 41,354-bp double-stranded DNA genome lacking detectable lysogeny-associated genes, antibiotic resistance determinants, and known bacterial virulence factors. In THP-1 macrophages, AUBFM01 exposure was associated with reduced cell viability and with enrichment of a resting/intermediate-like CD86-defined phenotype among the remaining cells, including after endotoxin reduction. These findings identify AUBFM01 as a lytic anti-Acinetobacter phage with antibiofilm activity and notable macrophage-associated effects that warrant further mechanistic and safety investigation. Full article

In this study, we aimed to isolate indigenous plant-growth-promoting rhizobacteria (PGPR) with high indole-3-acetic acid (IAA)-producing capacity from alfalfa rhizospheres in arid regions of Northwest China and systematically evaluate their bioacceleration effects on alfalfa growth. Fifteen bacterial strains were isolated from rhizosphere soils collected in Ningxia and Inner Mongolia. Among them, four high-IAA-producing strains were selected and identified as Brevundimonas sp. B3, Pantoea sp. P10, and Microbacterium sp. M1 and M7 based on 16S rDNA sequencing. Pot experiments showed strain-specific growth-promoting effects: P10 significantly increased plant biomass (increasing fresh weight by 10.04% and dry weight by 11.76%, with p < 0.05), while M7 notably enhanced plant height (by 16.48%, with p < 0.05) and branching. Physiological and cytological analyses revealed that the tested strains improved chlorophyll content (30–45% above the control), reduced malondialdehyde (MDA) levels (20–40% below the control), and differentially regulated root-tip cell elongation. Principal component analysis further supported the comprehensive promotive effects of these strains, with P10 exhibiting the highest overall performance (PC1–PC4 cumulative variance: 83.1%). Within the limitations of controlled pot experiments, these findings highlight the potential of native PGPR strains, particularly P10 and M7, as promising candidates for developing region-specific microbial inoculants with which to enhance alfalfa productivity in arid and semi-arid environments. Full article

This study aimed to evaluate the physicochemical characterization and antibacterial activity of the essential oil (EO) extracted from the leaves of Mentha rotundifolia (L.) Huds. Molecular interactions between bioactive ligand compounds, target bacterial proteins and DNA gyrase subunit B (GyrB), as well as an in silico ADMET prediction study, were also conducted. The EO was obtained by hydrodistillation of the plant leaves. The Gas Chromatography–Tandem Mass Spectrometry (GC-MS/MS) analysis revealed Rotundifolone (27.95%) and carvacrol (19.48%) as the major constituents. Other components identified included Piperitenone (6.09%), Cinerolon (4.73%), and Pulegone (4.47%). Antibacterial activity was assessed against six bacterial strains: Enterococcus faecalis CIP 103214, Salmonella Typhi CIP 5535, Staphylococcus aureus ATCC 9144, Bacillus cereus ATCC 33019, Streptococcus agalactiae IPM 24842, and Providencia alcalifaciens CIP 82.90T. The disk diffusion assay showed a strong inhibitory effect against E. faecalis (inhibition zone: 19.66 ± 0.3 mm), while the lowest minimum inhibitory concentration (MIC) was observed for B. cereus (0.58 ± 0.01 µL/mL). The time-kill kinetics assay showed a progressive inactivation of all tested bacterial strains after their exposure to EO for 8 h at MICs. Furthermore, Molecular docking showed remarkable affinities between EO components, target proteins and DNA gyrase subunit B (GyrB). Moreover, the in silico ADMET predictions provided preliminary insights into the safety-related properties of the major EO components. In addition, EO compounds have the potential to interact with bacterial structures. These findings highlight the in vitro antibacterial potential of the M. rotundifolia EO and suggest its promise as a natural source of bioactive compounds. Full article

Bacterial biofilms are structured microbial communities enclosed within a self-produced extracellular polymeric substance matrix composed of polysaccharides, proteins, extracellular DNA, and lipids. This matrix promotes adhesion, structural stability, and the development of heterogeneous microenvironments that restrict antimicrobial penetration and shield bacteria from host immune responses. As a result, biofilms are major contributors to chronic, recurrent, device-related, and difficult-to-treat infections, posing a major challenge for clinical management and antimicrobial stewardship. This review summarizes current understandings of biofilm biology, its clinical relevance, including the stages of biofilm development, the composition and protective roles of the matrix, and the physiological heterogeneity that arises during maturation. It also examines key mechanisms underlying biofilm tolerance and resistance, such as limited antibiotic diffusion, and sequestration, enzymatic inactivation, efflux pump upregulation, persister cell formation, and horizontal gene transfer. In addition, it highlights important clinical settings in which biofilms are implicated, including cystic fibrosis, chronic wounds, osteomyelitis, implant- or device-associated infections, and breast implant illness, in which persistent implant-associated biofilms and the resulting chronic inflammatory milieu have been hypothesized to contribute to local and systemic manifestations in a subset of patients. The review further discusses conventional and emerging approaches for biofilm detection alongwith real-time monitoring. Biofilm-associated infections remain difficult to eradicate because persistence is driven by multiple interconnected protective mechanisms. Effective management therefore requires integrated strategies that combine accurate detection with multifaceted therapies, including antibiotics alongside matrix-disrupting enzymes, quorum-sensing inhibitors, bacteriophages, metabolic reactivators, and nanotechnology-based delivery systems. Advances in multi-omics and system-level modeling will be essential for developing next-generation strategies to prevent, monitor, and treat biofilm-associated disease. Full article

Background: Prostate cancer (PCa) arises from complex interactions among host genetics, androgen signaling, and microbial communities. Emerging genomic evidence supports the presence of microbial consortia within prostate tissue, suggesting that microbial genes, metabolites, and host–microbe interactions may contribute to chronic inflammation, oncogenic signaling, and therapeutic resistance. Methods: We conducted a narrative review using targeted searches of PubMed and Google Scholar for studies published between 2020 and 2025, complemented by selected mechanistic reports published in March 2026. Human studies and experimental research providing mechanistic insights into prostate models were prioritized. Due to the heterogeneous methodologies, evidence was synthesized qualitatively, with an emphasis on genomic and signaling perspectives. Results: Low-biomass microbial DNA is consistently detected in prostate tissue. Proteomic analyses of Corpora amylacea suggest a “fossil record” of past infections through sequestered microbial DNA and antimicrobial proteins, potentially priming tissue for long-term carcinogenic processes, although contamination remains a key limitation. Recurrent bacterial and viral signals, including Cutibacterium acnes, Escherichia coli, Pseudomonas, Acinetobacter, human papillomavirus, Epstein–Barr virus, and cytomegalovirus, appear to converge on a restricted set of tumor-relevant pathways, including TLR–NF-κB, MAPK, PI3K/AKT/mTOR, cGAS–STING, and p53/pRb disruption. These interactions may promote cytokine production, oxidative stress, DNA damage, epithelial–mesenchymal transition, extracellular matrix remodeling, immune evasion, and resistance to therapy. The gut–prostate axis further links intestinal dysbiosis and microbial metabolites with systemic IGF-1 signaling and castration resistance. Conclusions: Microbial genomic consortia in the prostate and gut may shape inflammatory, metabolic, and immune networks that influence PCa initiation and progression. However, most available data remain correlative and are limited by low-biomass sampling, contamination risk, and heterogeneous study designs. Future research should prioritize rigorous contamination control, longitudinal and prostate-specific mechanistic studies, and integrated multi-omic approaches to clarify causality and identify actionable microbial targets for prevention, diagnosis, and therapy. Full article

The efficacy of traditional antimicrobial treatments has been largely compromised due to the high occurrence of multidrug-resistant (MDR) pathogens, therefore underlining the limitations of existing drug delivery mechanisms. Pathogens resist pharmacological treatment via different mechanisms, including efflux pump overexpression, biofilm formation, and enzymatic destruction. The application of nanorobotics or controllable nanoscale devices has gained considerable attention for overcoming shortcomings while connecting biomedical engineering, materials science, and microbiology. Despite advancements in nanomedicine, there is still no suitable nanorobotic system applicable against MDR pathogens. Previous studies highlighted device categories and materials but did not explain the detailed nanorobotic mobility, sensing, and programmability to counteract biological resistance. This review combines cross-disciplinary discoveries to design a mechanistic and translational model for nanorobotics effective in controlling infectious diseases while focusing on the advancements in nanorobotic technologies over the past six years (2020–2025), with emphasis on translational readiness, biosafety issues, scalability, regulation, and their mechanistic ability to overwhelm MDR complications. Databases from different publishers, including PubMed, Scopus, and Web of Science, were used to select studies focusing on the potential of emerging nanorobotic therapeutic technologies, such as magnetic microrobots, catalytic nanoswimmers, and DNA origami nanodevices, and their application to bacterial biofilms and antibiotic drug delivery. Evidence from the literature shows that magnetically driven microrobots, catalytic nanoswimmers, and DNA origami structures can actively destroy biofilms, enhance antibiotic penetration, and perform site-specific antimicrobial administration. Nevertheless, most of these innovations remain in the preclinical or prototype stage, hindered by biosafety issues, immunological reactivity, poor routing precision, energy source optimization, and a lack of regulatory and ethical frameworks, which are major challenges for clinical translation. Full article

Background/Objectives: Rapid, equipment-free molecular detection of bacterial pathogens at the point of care (POC) remains a critical challenge. Staphylococcus aureus is a leading cause of severe infections, necessitating simple and sensitive diagnostic tools. Methods: We developed an integrated assay combining helicase-dependent amplification (HDA) and rolling circle amplification (RCA) in a sequential ‘one-pot’ format. Asymmetric HDA generates short, single-stranded amplicons from S. aureus DNA, enabling specific padlock probe ligation and subsequent exponential RCA. For equipment-free visual detection, biotin-labeled nucleotides are incorporated during RCA, and products are captured on a silica membrane and detected using a streptavidin-HRP conjugate with 3,3′,5,5′-tetramethylbenzidine substrate, producing an unambiguous blue color. Results: The assay detected as few as 10¹ genome copies of S. aureus per reaction. Evaluation against a panel of nine non-target respiratory pathogens and human genomic DNA demonstrated 100% specificity, with no cross-reactivity. The entire procedure is performed isothermally at 65 °C in a single tube with a total assay time of approximately 90 min. Conclusions: This ‘one-pot’ HDA-RCA colorimetric assay combines high sensitivity and specificity for S. aureus in a user-friendly, almost equipment-free format. Its simplicity and robust visual readout make it a promising tool for POC diagnostics in resource-limited settings, enabling rapid clinical decisions without specialized instrumentation. Full article

Streptococcus parauberis is a major pathogen responsible for streptococcosis in both marine and freshwater fish species, causing substantial economic losses in aquaculture. The increasing prevalence of multidrug resistance has highlighted the urgent need for alternative disease control strategies. Interference with bacterial quorum sensing (QS) systems represents a promising approach. This study aimed to identify and biochemically characterize an Rgg-family transcriptional regulator and evaluate its potential as a target for quorum sensing-related regulatory interference in vitro. We hypothesized that this Rgg regulator may function as a quorum sensing-associated transcription factor capable of promoter binding and modulation by small molecules. Bioinformatic analyses were used to identify the rgg gene encoding an Rgg-family transcriptional regulator and predict its structural features. The gene was cloned, heterologously expressed, and purified. Promoter binding activity was examined using electrophoretic mobility shift assay (EMSA), and key amino acid residues were identified through site-directed mutagenesis. The inhibitory effect of the cyclic peptide cyclosporin A (CsA) on Rgg-promoter binding was further assessed. The rgg gene (864 bp) encoding a 287-amino-acid protein (34.1 kDa) was successfully identified and expressed. Purified Rgg specifically bound to its own promoter region in a concentration-dependent manner. Mutations at conserved arginine residues R12 and R15 within the helix-turn-helix DNA-binding domain abolished promoter binding activity. Furthermore, CsA disturbed Rgg-promoter binding in a dose-dependent manner. This study provides the first in vitro characterization of an Rgg-family transcriptional regulator in fish-derived S. parauberis. The findings expand current understanding of Rgg-family regulators potentially associated with quorum sensing in aquatic streptococci and provide a preliminary basis for further investigation of quorum sensing-related regulatory interference strategies for controlling streptococcal diseases in aquaculture. Full article

Foodborne pathogens such as Klebsiella aerogenes pose a threat to food safety, highlighting the need for rapid, reliable detection methods amid rising contamination risks in production chains. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed and validated to detect the histidine decarboxylase (HDC) gene of K. aerogenes. The assay was optimized for specificity and sensitivity, tested on pure bacterial genomic DNA and artificially contaminated food matrices (vegetables and meats), and evaluated against real-time PCR (qPCR). To evaluate performance under different DNA quality conditions and simulate laboratory versus on-site workflows, two extraction approaches were compared: a standard laboratory protocol yielding high-purity DNA and a crude extraction method producing low-purity DNA, mimicking the presence of inhibitors commonly encountered in routine analysis and enabling practical on-site detection where commercial kits are not feasible. The developed LAMP assay achieved maximum specificity with no cross-reactivity to related species, limits of detection of 240 fg/reaction for pure bacterial DNA and 0.4 pg/µL in K. aerogenes artificially contaminated food samples, and a reaction time under 30 min—outperforming real-time PCR in speed and robustness. This cost-effective method provides a scalable tool for near-real-time monitoring of K. aerogenes in food production, enhancing safety and enabling early outbreak detection. Full article