Search Results (1,790)

Equine bacterial abortion presents substantial economic and One Health challenges; however, comprehensive epidemiological data from China are limited. This study sought to ascertain the overall prevalence of key pathogens—namely, Chlamydia spp., Coxiella burnetii, Salmonella abortus equi, and Brucella spp.—in equine populations in northwestern China. In this study, we aimed to further elucidate the characteristics of co-infections, profile antimicrobial resistance genes, and identify associated risk factors. Conducted as a cross-sectional analysis across four provinces, we collected 508 blood samples and 24 abortion tissue samples from 15 farms. Pathogen detection was performed using ELISA and real-time PCR, complemented by a targeted PCR panel screening for 29 AMR genes. The highest prevalence was observed for S. abortus equi (serology: 35.03%; molecular: 23.03%), followed by C. burnetii (28.94%; 15.35%) and Chlamydia spp. (18.90%; 14.17%). No PCR-confirmed cases of Brucella spp. were detected, despite low-level seropositivity. Notably, donkeys and horses aged 5–10 years exhibited higher positivity rates, and co-infections were common, particularly S. abortus equi + C. burnetii (n = 44). Among the 196 PCR-positive samples, extended-spectrum beta-lactamase (ESBL) genes were predominant, with CTX-M (n = 158) and TEM-1 (n = 106) being the most prevalent. Additionally, we identified a high prevalence of genes conferring resistance to fluoroquinolones (qnrA/B), tetracyclines (tetM), macrolides (ermA/B/C), and sulfonamides (sul1), along with sporadic occurrences of carbapenemase genes. This study presents the inaugural comprehensive analysis of pathogen prevalence and associated antimicrobial resistance (AMR) gene carriage in equine abortion cases in northwest China. The findings highlight the imperative for integrated serological and molecular surveillance, revealing a significant discrepancy between empirical therapeutic approaches and the prevalent resistance genotypes. Consequently, this research lays the groundwork for evidence-based biosecurity measures and antimicrobial stewardship within a One Health framework. Full article

Lead (Pb) disrupts mitochondrial function, but its impact on the mitochondrial dynamics and biogenesis during early brain development remains insufficiently understood. This study aimed to investigate the effects of pre- and neonatal Pb exposure on the processes involved in mitochondrial network formation in the brains of rat offspring, simulating environmental exposure. We quantified mRNA expression (qRT-PCR) and protein levels (ELISA) of key mitochondrial fusion (Mfn1, Mfn2, Opa1), fission (Drp1, Fis1) regulators, as well as biogenesis markers (PGC-1α, TFAM, NRF1) in the hippocampus, forebrain cortex, and cerebellum of rats exposed to Pb. Mitochondrial ultrastructure was evaluated using transmission electron microscopy (TEM), and the expression of mitochondrial electron transport chain (ETC) genes was analysed (qRT-PCR). Furthermore, to examine the involvement of the cGAS–STING pathway in Pb-induced neuroinflammation, we measured the expression of ISGs (qRT-PCR), TBK1 phosphorylation (Western blot), and 2′,3′-cGAMP synthesis (ELISA). Our results showed that Pb exposure markedly reduced PGC-1α and region-specific NRF1 levels, broadly supressed fusion proteins (Mfn1, Mfn2, Opa1), increased Fis1, and depleted Drp1. ETC gene expression (mtNd1, mtCyb and mtCo1) were upregulated in a brain-structure-dependent manner. These molecular changes were accompanied by pronounced mitochondrial morphological abnormalities. Despite upregulation of Mx1, Ifi44, and Sting1, along with synthesis of 2′3′-cGAMP, TBK1 activation was not detected. All these findings demonstrate that early-life Pb exposure, even low-dose, disrupts mitochondrial biogenesis and the fusion–fission machinery, thus impairs brain energy homeostasis, and implicates mitochondria as central mediators of Pb-induced neuroinflammation and neurodevelopmental toxicity. Full article

Gold nanoparticles (AuNPs) synthesized via picosecond pulsed laser ablation were investigated as enhancers of methylene blue (MB)-mediated photodynamic therapy (PDT) against Escherichia coli. AuNPs produced at 532 and 1064 nm with frequencies of 20–50 kHz showed frequency- and size-dependent effects, with 50 kHz yielding the highest particle concentrations and smaller particles enhancing reactive oxygen species (ROS) generation. UV-Vis and fluorescence spectroscopy confirmed nanoparticle formation and plasmonic properties consistent with TEM measurements. Photobleaching assays demonstrated that AuNPs significantly increased MB singlet oxygen generation, while the efflux pump inhibitor INF-55 further amplified bacterial killing without altering net ROS yield. In vitro assays revealed that INF-55 combined with MB/AuNPs achieved ~59% higher bacterial deactivation compared to MB/AuNPs alone. Molecular docking confirmed stronger binding of INF-55 to the AcrB efflux pump (−9.1 kcal/mol) than MB, supporting its role as a competitive inhibitor that promotes intracellular MB retention. These findings establish a dual-action PDT strategy in which AuNPs enhance ROS production and INF-55 augments antibacterial efficacy via efflux pump inhibition. Together, this platform provides a proof of concept for future translation to biofilm- and tissue-based infection models, and potentially to localized clinical applications such as prosthetic joint, catheter-associated, or chronic wound infections where conventional sterilization or systemic antibiotics are insufficient. Full article

Metal–Organic Frameworks (MOFs) have diverse applications due to their tunable porosity, large surface area, and diverse chemical functionalities. Among them, one of the most researched MOFs is MIL-101(Cr), which, in addition, is very stable in water. We have used a commercially available substance with approximately 300 nm large crystals for the preparation of a sensing nano-thin layer for the emerging water contaminant PFOS, due to its high selectivity towards this compound. Here, we have synthesized 20 nm sized crystals of MIL-101(Cr), which are among the smallest reported, and compared them to the same material with 300 nm sized crystals. The material was characterized by TEM and XPS. It was possible to prepare insoluble monolayers at the air–water interface (Langmuir films), which were characterized with film compression isotherms, Brewster angle microscopy, and surface potential measurements. The Langmuir–Blodgett (LB) method was used to deposit monolayers on Si wafers and 434 MHz Surface Acoustic Wave resonator simultaneously. The LB layers were very stable over time. The smaller-sized MIL-101 (Cr) crystals exhibit denser, more homogeneous water coverage and packing upon compression, with no observable 10–100 µm aggregates. LB monolayers from the 20 nm particles have approximately six times lower surface roughness. The LB monolayer is far from being smooth, but this will allow excellent access to the MOF pores by the tested analyte in a chemical sensing application. The lack of research on depositing presynthesized MOFs using probably the best method for nanoarchitectonics—the LB method—is addressed. The 20 nm sized MOF crystals are the smallest deposited by this method so far. Full article

Mesoporous silica and its derivatives might enable applications ranging from biomedicine to petrochemical processing. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and N₂ adsorption–desorption measurements are usually used to characterize the ordered porous system. However, none of these methods convey the full surface information. In this work, a low-voltage scanning electron microscope (LVSEM) with beam deceleration technology was employed to image detailed surface structures of ~2 nm pore size silica (MCM-41), SBA-15, KIT-6, and mesoporous silica nanospheres (MSNSs). The prospects for the development of this application of ultra-high-resolution scanning electron microscopy (SEM) are discussed in the characterization of the ordered porous materials. We demonstrate that the complete dimension range of the mesoscopic surface structure (2–50 nm) could be resolved by current low-voltage SEM technology. Full article

Zinc sulfide nanomaterials (ZnS NMs) are widely used in many important technological applications, and the performance efficiency is determined by the nanostructure, size, and shape. This indicates that achieving a desirable surface architecture is pivotal for any application. One of the efficient and cost-effective techniques, the hydrothermal method, offers uniform size, specific shape, and bulk synthesis capability. This research deals with the preparation of ZnS NMs exhibiting unique surface structures such as spherical, nano-pentagon, and nano-hexagon shapes through employing different zinc precursors and surfactants. The obtained material’s crystal structure was classified as cubic sphalerite and exhibited high purity, as analyzed by XRD, SEM-EDX, TEM, and XPS. Furthermore, the synthesized ZnS NMs were tested for their shape-dependent biosensing application, such as specific antibacterial tests against routine human pathogens such as E. coli, K. pneumoniae, and S. aureus. Several antibacterial methods, such as bacterial colony plate count, growth inhibition analysis, and minimum inhibition concentration (MIC) measurements were carried out. The results confirmed that the antibacterial action in the method employed was dependent on three factors: the NM shape, concentration, and type/nature of bacteria. Especially, the prepared ZnS NMs exhibited excellent antibacterial sensing characteristics, as observed from the lower MIC values in the range of 15.6~250 µg/mL. Full article

In this work, nickel oxide nanoparticles (NiO NPs) were synthesized sonochemically in the ionic liquid 1,2-(propanediol)-3-methylimidazolium hydrogen sulfate ([PDOHMIM⁺][HSO₄⁻]) at different loadings (8 wt.%, 15 wt.%, and 30 wt.%), and subsequently coated with polyethylene glycol (PEG). Structural characterization (XRD, FTIR, TEM, TGA) confirmed a cubic NiO spinel phase with an average crystallite size of ~8 nm, which increased to 20–28 nm after PEG coating. Electrical measurements (100 Hz–1 MHz) showed that AC conductivity (σAC) increased with both frequency and NiO content, whereas the dielectric constant (ε′) and loss tangent (tan δ) decreased with frequency. DFT calculations (B3LYP/6–311+G(2d,p)) on the [PDOHMIM⁺][HSO₄⁻] ion pair showed that there were strong hydrogen bonds, an uneven charge distribution, and stable electrostatic interactions that help keep NiO NPs stable and spread them evenly in the ionic liquid. In general, both experimental and theoretical studies show that PEG-coated [NiO NPs + IL] nanostructures exhibit improved dielectric stability, enhanced interfacial polarization, and tunable electronic properties. Full article

Background/Objectives: Hesperetin (HSP) is a bioactive flavonoid known for its strong antioxidant and anti-inflammatory properties. However, its low water solubility (1.36 ± 0.30 μg/mL) and poor oral bioavailability (~20%) greatly hinder its potential in nutraceutical applications. Methods: Using the solvent dispersion method, nanoparticles composed of HSP, hydroxypropyl-β-cyclodextrin (HPBCD), and polyvinylpyrrolidone K30 (PVPK30) were prepared and collectively termed HHPNP. Characterization involved particle size measurement, FTIR, XRD, SEM, and TEM. Antioxidant activity was evaluated using DPPH and ABTS⁺ radical scavenging assays. In vitro dissolution testing was performed at pH 1.2 and pH 6.8 to compare HHPNP with physical mixtures, and release behavior was assessed using both gelatin (non-vegetarian) and HPMC (vegetarian) capsules. Results: The optimal formulation (1:15:12) produced uniformly distributed spherical nanoparticles with a mean size of 14.87 ± 0.49 nm and achieved an 827-fold increase in water solubility compared with raw HSP. FTIR analysis indicated hydrogen bond formation, and XRD confirmed a complete transition from a crystalline to an amorphous state. In aqueous environments, HHPNP demonstrated markedly improved antioxidant activity, with DPPH and ABTS⁺ radical scavenging comparable to HSP solutions prepared in methanol. In vitro dissolution testing revealed rapid release at both pH 1.2 (>65% in 10 min) and at pH 6.8 (70% in 5 min). In contrast, physical mixtures only released 10–30% over two hours. T50% values at pH 1.2 were 17.8 min (gelatin) and 16.8 min (HPMC). At pH 6.8, T50% values were 17.6 min (gelatin) and 7.5 min (HPMC). Both capsule types matched the HHPNP in release at 120 min, and these comparable profiles indicate the formulation’s stability and adaptability across capsule variants. Conclusions: This nanoparticle-based delivery system, leveraging molecular inclusion and amorphization, significantly enhanced the solubility, bioactivity, and release efficiency of HSP, offering a potent platform for oral flavonoid-based dietary supplements. Full article

Nanomaterial-based systems (NBS) have emerged as transformative elements in advanced surface engineering, offering superior corrosion resistance, mechanical strength, and tribological resilience governed by unique phenomena inherent to the nanoscale. However, bridging the knowledge gap between these enhanced physicochemical properties and the metrological tools required to quantify them remains a critical challenge. This review provides a comprehensive examination of the fundamental mechanisms, state-of-the-art experimental techniques, and computational strategies employed to probe NBS behavior. The article first elucidates the core mechanisms driving performance, including passive barrier formation, stimuli-responsive active corrosion inhibition, grain boundary strengthening, and the formation of protective tribo-films by 2D nanomaterial-based systems. Subsequently, the article evaluates the transition from conventional macroscopic testing to high-resolution in situ characterization, highlighting the capabilities of High-Speed Atomic Force Microscopy (HS-AFM), Liquid Cell Transmission Electron Microscopy (LC-TEM), and nanoindentation in visualizing dynamic defect evolution and measuring localized mechanical responses. Furthermore, the indispensable role of computational materials science—specifically Molecular Dynamics (MD) and Machine Learning (ML)—in predictive modeling and elucidating atomic-scale interactions is discussed. Finally, persistent challenges regarding substrate interference, sample heterogeneity, and instrumentation limits are addressed, concluding with a perspective on future research directions focused on standardization, operando testing, and the development of AI-driven “Digital Twins” for accelerated testing and material optimization. Full article

A method for synthesizing an in situ composite based on the A201 aluminum–copper alloy is proposed, utilizing a Self-propagating High-temperature Synthesis (SHS) reaction via the SHSB (Self-propagating High-temperature Synthesis in Bath) process. In this study, a novel synthesis approach is presented, involving a liquid titanium–solid carbon reaction to form titanium carbide (TiC) particles within the A201 alloy, in contrast to the typical solid–solid (Ti–C) reaction. The outcome of this process is the formation of TiC particles, which are primarily located along grain boundaries and contribute to grain refinement, particularly of the (α)Al phase. A focused study of the in situ TiC-reinforced composite was conducted using XRF, optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Vickers microhardness measurements. The present study has a basic research character and focuses on the description of a novel synthesis method for the production of titanium carbides. This reaction proceeds as a solid–liquid type reaction between carbon and titanium. Phase and transmission analyses confirmed the formation of titanium carbides. Furthermore, based on the A201 alloy, the potential for alloy modification was demonstrated, which may inhibit the growth of primary α-aluminum phase grains and thus reduce the susceptibility to hot cracking. Full article

Encapsulins are microbial protein nanocompartments that spatially organize and sequester specific biochemical processes, including iron storage. While their protein shells have been extensively characterized, the composition and structure of their mineral cores remain less understood. Here, we use bright field transmission electron microscopy (BF TEM), high-angle annular dark-field scanning TEM (HAADF STEM), energy-dispersive X-ray (EDX), and electron energy-loss spectroscopy (EELS) in STEM to characterize the iron-containing mineral granules within the Myxococcus xanthus encapsulin system at near atomic resolution. We find that the internal nanoparticles are smaller (~2 nm) and more numerous (up to ~2200 per encapsulin) than previously reported. These nanoparticles are typically amorphous and have a composition consistent with FePO₄ (measured Fe:P ratio of ≈1:1.2). Each encapsulin contains on average ~8500 iron atoms, corresponding to a volumetric density of 2.1 atoms/nm³. Phosphorus incorporation inhibits crystallization, whereas growth in phosphorus-free media leads to the formation of nano-crystalline goethite [α-FeO(OH)]. Full article

The cannabidiol (CBD)-rich cannabis extract CAN296 shows anti-inflammatory and anticancer activity relevant to oral lichen planus (OLP), oral graft-versus-host disease (oGVHD), and oral squamous cell carcinoma (OSCC), but its high lipophilicity limits aqueous dispersion. This study developed a stable Tween-based nanoemulsion optimized for oral mucosal delivery. Ethanol-dissolved CAN296 was nanoemulsified using a 1% Tween/Span system. Physical stability was visually assessed; droplet size and morphology were examined by dynamic light scattering (DLS) and transmission electron microscopy (TEM); and wettability was measured by static contact angle (SCA). Additional evaluations included temperature stability (25 °C vs. 4 °C), in vitro release using a dialysis membrane, and scanning electron microscopy (SEM) of membrane-associated droplets. Nanoemulsions with ≥80% Tween 80 incorporated CAN296 up to 800 µg/mL, clear at 400 µg/mL, and uniformly turbid at 800 µg/mL. DLS and TEM confirmed spherical nanoscale droplets, and SCA indicated favorable cohesion and wettability. Stability was maintained for 30 days at 4 °C. Dialysis studies demonstrated strong membrane association with limited diffusion, supported by SEM visualization of membrane-bound droplets. The Tween-dominant (≥80%) nanoemulsion stably incorporated CAN296 up to 800 µg/mL, demonstrated nanoscale uniformity, improved 4 °C stability, and strong membrane retention under static conditions, suggesting potential for localized oral delivery. Full article

In this study, we present a convenient approach for the preparation of viscose, maghemite, goethite, and poly(methylhydro-dimethyl)siloxane hybrid materials possessing electromagnetic shielding properties, thermal stability, strong magnetization, and very good hydrophobicity. The chemical compositions, morphologies, thermal properties, magnetic measurements, wettability, and dielectric properties of the prepared composites and pristine precursors were thoroughly investigated by Fourier transform infrared spectroscopy (FTIR), scanning and transmission electron microscopy (SEM and TEM), thermal degradation (TG, DTG, and DTA), magnetic measurements (magnetization, thermomagnetic curves, relative magnetic permeability), and dielectric spectrometry. Moreover, the electromagnetic shielding properties of pristine viscose and the final composite were assessed. Full article

Background: Rabies virus (RABV) causes approximately 59,000 human deaths annually. Current pre- and post-exposure vaccination relies on inactivated vaccines (INVs) with limited yield and immunogenicity. We engineered a dual-cationic LNP-based nucleocapsid-like nanostructure (NLS) that co-encapsulates RABV G-mRNA and recombinant RABV-N to engage MHC-I/II pathways and enhance protection. Methods: A pVAX-RABV-G plasmid containing 5′/3′UTRs, Kozak, and poly(A) was transcribed in vitro. RABV-N with an N-terminal 6× His tag was expressed in E. coli BL21(DE3) and purified by Ni-Sepharose affinity chromatography. Dual-cationic LNPs (DHA, DOTAP Cl, mPEG-DTA2K, DOPC) were formulated by microfluidics at a 4:1 (G-mRNA:RABV-N) mass ratio. Vaccine quality was assessed by encapsulation efficiency, DLS, PDI, zeta potential, and TEM. Mice received empty LNPs, INV, G-mRNA, or NLS under varied schedules and doses. ELISA measured RABV-G/N-IgG; RFFIT determined neutralizing antibody (nAb) titers; ELISPOT quantified CTL response; qPCR assessed T-cell activation genes. On day 35 after the first immunization of vaccines, mice were challenged intramuscularly with 25 LD₅₀ of CVS-24. Results: G-mRNA purity was >95% and drove strong RABV-G expression in 293T cells. Purified RABV-N was approximately 52 kDa, >90% pure, and reactive to anti-His and anti-N antibodies. NLS achieved >95% encapsulation, a diameter of 136.9 nm, PDI 0.09, and a +18.7 mV zeta potential. A single dose yielded approximately 10 IU mL⁻¹ nAb by day 7; two doses peaked at approximately 1000 IU mL⁻¹. Mice showed 100% survival and no viral rebound in brain, spinal cord, and sciatic nerve. NLS induced stronger MHC-I/II-linked cellular immunity and higher RABV G/N-specific IFN-γ spot frequencies than G-mRNA or INV. Conclusions: The dual-antigen NLS vaccine co-delivering G-mRNA and RABV-N via dual-cationic LNPs robustly activates MHC-I/II, rapidly generates high-titer nAb (≥10 IU mL⁻¹ within 1 week), and sustains potent CD8⁺ CTL and CD4⁺ Th responses. A two-dose regimen (days 0 and 21) conferred complete protection, supporting the NLS platform as a next-generation rabies vaccine candidate. Full article

An ultrathin Al layer was introduced into AZO/Cu/AZO films to further enhance the optoelectronic performance. The AZO/Al/Cu/AZO films were deposited on glass substrates by DC and RF magnetron sputtering; the microstructure and optoelectronic properties were analyzed by XRD, SEM, AFM, TEM, visible spectrophotometer, and Hall effect measurement system. The results indicated that the Al layer played a crucial role in modulating the crystallization behavior and optoelectronic properties of the films, exhibiting a distinct thickness-threshold effect. At an Al layer thickness of 1 nm, the film exhibited optimal optoelectronic performance, achieving a high F_OM of 0.71 Ω⁻¹, a high transmittance of 85%, and a low resistivity of 5.7 × 10⁻⁵ Ω·cm. However, when the Al layer thickness exceeded 1 nm, the crystallinity of the films deteriorated significantly, the grain boundary scattering and light absorption effect enhanced, leading to the deterioration of photoelectric properties. The introduction of the Al layer significantly improved the stability of the films, and the AZO/Al(2 nm)/Cu/AZO film exhibited the best temporal stability after being exposed to air for 20 months. Full article