Search Results (759)

Background/Objectives: Porcine epidemic diarrhea (PED) is a highly contagious enteric disease caused by porcine epidemic diarrhea virus (PEDV) and is associated with severe clinical signs and high mortality in neonatal piglets. Vaccination is an important strategy for PED control through the induction of humoral immunity. This study aimed to compare immune responses induced by inactivated and live-attenuated PEDV vaccines and to evaluate a heterologous prime-boost vaccination strategy in PEDV-naïve replacement gilts. Methods: Twenty-four PEDV-naïve replacement gilts were randomly assigned to four groups: unvaccinated control, inactivated vaccine administered twice (K/K), live-attenuated vaccine administered twice (L/L), and live-attenuated priming followed by an inactivated booster (L/K). Pigs received two intramuscular vaccinations at 16 weeks of age and two weeks later. Serum samples collected up to 42 days post-vaccination were analyzed for PEDV-specific IgG and IgA antibodies by ELISA, and serum-neutralizing antibody titers were determined using a serum neutralization test. Results: The L/K regimen induced the highest PEDV-specific IgG responses, with peak levels at day 28 post-vaccination that were significantly higher than those in the K/K and control groups. Serum-neutralizing antibody titers were significantly higher in the L/K and L/L groups than in the K/K and control groups. Serum IgA responses were low and transient across all vaccination groups. Conclusions: A heterologous prime-boost vaccination strategy using a live-attenuated PEDV vaccine followed by an inactivated booster induces strong systemic humoral immune responses in replacement gilts and represents a promising approach for PEDV vaccination programs. Full article

This study focuses on the storage process of coffee beans, employing electron beam irradiation (EBI) to investigate the comprehensive effects of different irradiation doses on coffee beans and their storage process, including physicochemical indicators, microbial abundance, and flavor compounds. The results showed that a 2 kGy dose of EBI could effectively reduce the total number of bacteria, molds, and yeasts in green coffee beans (GCBs), while a dose of 4 kGy can completely inactivate the bacteria and maintain this effect for one month. Compared with the control sample that has not undergone processing by EBI (CK), the crude fat content of the irradiated samples decreased, accompanied by a significant increase in acid value. After 30 days of storage, compared with the CK-30 sample, EBI treatment significantly reduced both the moisture content and overall brightness value of GCB. The analysis of aroma compounds in roasted coffee beans (RCBs) revealed that substances related to Maillard reaction, caramelization reaction and sugar degradation, such as 2-Furanmethanol and acetic acid, changed in the irradiated samples, but had no significant effect on the characteristic components like caffeine and the aroma detected by the electronic nose. The obtained results provide a scientific basis for applying irradiation technology to the preservation of coffee beans. Full article

Fowl adenoviruses are opportunistic emerging viruses that spread widely in fowls, infecting birds of all ages, including young broiler chicks. This study aims to genotype the current adenovirus strains associated with inclusion body hepatitis hydropericardium syndrome (IBH-HPS) among infected broilers in Upper Egypt and to evaluate their pathogenic features. In 2024, 100 tissue samples were collected across Assiut and Sohag governorates in Upper Egypt for genetic characterization and pathogenicity evaluation. FAdVs were detected in 22% (11/50) of flocks. Typical FAdV lesions of dead embryos were observed after seven days post egg inoculation. Regarding the PCR assay of the hexon gene, only 8 of 30 samples were confirmed positive at 897 bp, yielding a 26.6% positivity rate. The remaining samples were considered negative using established RT-qPCR protocols for other viral pathogens. Partial sequencing of the hexon gene revealed that FAdV isolates (n = 4) clustered within FAdV species-D serotype 2/11, as determined by phylogenetic analysis. The four isolates shared (98–99%) and (94–100%) nucleotide and amino-acid similarities to FAdV-D of Israeli strains (2019–2020) and contemporary Egyptian isolates (2022), respectively, and low genetic divergence (54–81%) in comparison with other documented species. The amino acid sequence alignment and 3D structure indicate that the four immunogenic HVRs are located in the L1 region of the hexon protein, and that the highly conserved ⁹¹GQMTT⁹⁵, a specific region for FAdV-D serotype 2/11, is present. Regarding pathogenicity, the gross and histopathological findings observed clearly demonstrate the systemic pathogenicity of FAdV-2/11 in the infected group, with a final mortality rate of 30% at seven days post-infection (dpi). The FAdV DNA in hepatic tissues and cloacal swabs was confirmed by the PCR method at 3 dpi and 5 dpi. These results emphasize the circulating of FAdV-2/11 species D in Upper Egypt and highlight the significant need for a single inactivated vaccine that effectively targets the relevant FAdV serotypes to achieve broader and more efficient protection. Full article

This study investigates the elaboration, structural characteristics, and antibacterial performance of silver-based nanoparticles obtained via a hydrolytic chemical route, with and without assistance from ultrasound and microwave irradiation. Two silver nitrate precursor concentrations (1 M and 2 M) were employed to evaluate the influence of synthesis conditions on phase composition, morphology, and antimicrobial efficiency. The obtained powders were characterized by ATR-FTIR, X-ray diffraction (XRD), and scanning electron microscopy (SEM). XRD analysis revealed that drying at 120 °C led to oxide-rich systems dominated by Ag₂O, with minor contributions from metallic Ag and carbonate species, while calcination at 550 °C resulted in complete phase transformation into highly crystalline metallic silver. SEM observations demonstrated that precursor concentration and synthesis assistance strongly affect particle size, aggregation degree, and surface morphology. Ultrasound- and microwave-assisted synthesis promoted finer crystallite sizes and more homogeneous particle distributions compared to non-assisted routes. The antibacterial activity was evaluated against Escherichia coli (Gram-negative) and Clostridium perfringens (Gram-positive, anaerobic, spore-forming). Oxide-rich samples, particularly Ox.Ag/2 M, exhibited rapid and complete bacterial inactivation within 30 min, while metallic silver samples showed time-dependent antibacterial behavior, achieving full inhibition after 4 h. The results demonstrate that antibacterial efficiency is governed by a synergistic interplay between silver oxidation state, nanoscale morphology, and surface reactivity. These findings highlight the potential of tailored silver-based nanomaterials as effective antibacterial materials for biomedical, food safety, and environmental applications. Full article

Lumpy Skin Disease (LSD) is a transboundary bovine viral disease. It has a significant economic impact and is caused by the Lumpy Skin Disease Virus (LSDV). Effective surveillance tools are essential for the early detection of infection, outbreak control, and assessment of vaccination coverage in endemic regions such as India. In this study, an in-house ELISA based on inactivated whole-virus antigen (WVA) was developed, optimized, and validated for the detection of LSDV antibodies in cattle. Its field applicability was assessed through a cross-sectional seroprevalence survey conducted across five Indian states. A local field isolate of LSDV (strain 5-Chitra) was cultured in MDBK cells, inactivated using binary ethylenimine (BEI), and used as the antigen source. The assay was optimized by checkerboard titration and evaluated against the Serum Neutralization Test (SNT). Diagnostic sensitivity and specificity were evaluated using the receiver operating characteristic (ROC) curve and area under the curve (AUC) analyses, while cross-reactivity was assessed using sera positive for HS, IBR, BQ, MCF, GTP, SPP, CE, FMD, and Brucellosis. Assay reproducibility was confirmed through inter- and intra-laboratory validation. For the seroprevalence study, 3230 cattle serum samples were collected using a stratified random sampling design across five Indian states, and logistic regression analysis of a subset of 1302 samples was performed to assess the influence of age and sex on LSDV seropositivity. Checkerboard titration identified optimal ELISA conditions at 50 ng of antigen per well, a 1:150 serum dilution, and a 1:10,000 dilution of anti-bovine HRP-conjugated secondary antibody. The WVA-ELISA demonstrated excellent diagnostic performance, with 100% sensitivity, 95% specificity, and no cross-reactivity with other ruminant bacterial or viral pathogens, and showed high laboratory reproducibility (κ > 0.96). Seroprevalence ranged from 50.6% to 71.1% across the five states, indicating widespread exposure to LSDV. Risk factor analysis revealed significantly higher odds of seropositivity among calves (≤1 year old) and female cattle, suggesting age- and sex-dependent susceptibility. Full article

Background/Objectives: Porcine epidemic diarrhea virus (PEDV), particularly the emerging GII genotype, poses a severe threat to the swine industry in affected regions, primarily in Asia. Current vaccines based on classical strains often provide limited cross-protection against these heterogeneous variants, though it should be noted that these vaccines are primarily designed to induce maternal immunity in sows. The objective of this study was to develop a novel inactivated vaccine using an emerging PEDV GIIc variant and evaluate its immunogenicity and cross-protective efficacy against heterologous strains. Methods: A novel PEDV strain, designated PEDV-HeN2024, was isolated from clinical samples and identified through cell culture, immunofluorescence assay (IFA), genetic sequencing, and phylogenetic analysis. An inactivated vaccine was prepared by emulsifying the purified virus with ISA 201 VG adjuvant (1:1, v/v). Immunogenicity was assessed in piglets by measuring virus-neutralizing antibody titers and PEDV-specific IgG levels. Cross-protective efficacy was evaluated through in vitro neutralization assays and in vivo challenge studies with homologous GIIc and heterologous GIIa and GIIb strains. Results: The isolated PEDV-HeN2024 strain demonstrated pathogenicity, causing severe diarrhea and 100% mortality in PEDV-naïve neonatal piglets. Sera from vaccinated animals showed potent cross-neutralizing activity against homologous GIIc, as well as heterologous GIIa and GIIb strains. In challenge studies, vaccinated piglets were significantly protected against clinical disease, showing no diarrhea or viral shedding, and maintained normal intestinal architecture. Conclusions: The inactivated vaccine developed from the emerging PEDV GIIc variant elicits robust humoral immunity and provides cross-protection against prevalent heterologous GII strains. These findings highlight its potential as a promising spectrum vaccine candidate for controlling PEDV outbreaks. This study underscores the importance of using recently circulating strains for vaccine development to overcome the limitations of current vaccines. Full article

This study aimed to develop natural, safe, and effective antimicrobial packaging materials for extending the shelf life of chilled pork during refrigeration. Emodin-chitosan (Em-Cs) composite films with varied concentrations were developed by combining the casting method with photodynamic inactivation technology, utilizing chitosan as the matrix and emodin as the functional photosensitizer for active packaging. The optical, mechanical, and barrier properties of the composite films were examined. The inhibitory effects of the samples on Escherichia coli, Salmonella Derby, Staphylococcus aureus, and Pseudomonas fragi under 450 nm blue light irradiation were evaluated. The results demonstrated that the Em-Cs composite film exhibited excellent transparency, mechanical strength, and water barrier properties, with good compatibility between emodin and chitosan. Under light irradiation, the composite film generates reactive oxygen species (ROS), whose bactericidal efficacy depends on the concentration of emodin and the duration of light exposure. When applied to chilled pork packaging, this composite film inhibited bacterial growth within the meat for 10 days, effectively retarding pH increase, lipid oxidation, and volatile basic nitrogen accumulation. The present study proposes a novel methodology for the application of photodynamic technology in the context of food preservation, and it presents a new type of natural antimicrobial packaging material for the preservation of chilled pork. Full article

Background: Blue laser light has been the subject of research regarding the inactivation of microorganisms as a possible alternative to chemical treatment methods for a number of years. In dentistry, blue light could be used, for example, in the treatment of periodontitis/peri-implantitis, as well as in endodontics and against caries. It could serve as an alternative or supplement to traditional chemical and/or invasive methods. The antimicrobial effectiveness of a blue laser in relation to the speed of treatment is investigated using three different microbial test organisms in order to identify possible species differences. Methods: The test organisms Enterococcus faecalis, Streptococcus mutans, and Candida albicans were applied to smooth zirconium discs and treated twice with a diode laser at 445 nm wavelength with a traversing speed of 1, 2, and 4 mm/s. The antimicrobial effect was analysed based on the resulting colony-forming units on agar plates. The temperature was measured during the treatment. Preliminary tests were carried out using the MTT dye test to determine relevant setting parameters and the required energy dose. Results: Statistically significant differences were found between the negative control and the treated samples for all three tested organisms, with a maximum viability reduction of 1.8 log₁₀ CFU/mL for Enterococcus faecalis, 2.5 log₁₀ CFU/mL for Streptococcus mutans, and 1.0 log₁₀ CFU/mL for Candida albicans at 1 mm/s traversing speed, regarding estimated marginal means (p < 0.001). The temperature on the substrate surface reached 30 to 42 °C for all samples evaluated. Conclusions: Blue laser light (445 nm) demonstrates antimicrobial activity, which increases with prolonged exposure. Further research is needed to assess all key influencing parameters and define possible clinical applications. Full article

Exaggerated immune responses to respiratory viruses may contribute to increased morbidity in older adults. To investigate virus-specific immune activation in this population, we developed an ex vivo whole blood stimulation model using samples from 30 healthy individuals aged ≥65 years. Whole blood was stimulated with UV-inactivated influenza A virus (IAV), respiratory syncytial virus (RSV), and SARS-CoV-2, and the expression of 22 immune-related genes was assessed by quantitative RT-PCR array. All three viruses elicited responses with marked variability across individuals, as well as differences in the magnitude and distribution of cytokine expression across stimuli. RSV stimulation was associated with relatively higher expression of inflammatory mediators, while IAV and SARS-CoV-2 induced greater expression of Type I interferon. SARS-CoV-2 also led to an increased expression of regulatory cytokines. Although individual responses varied, correlation analysis indicated coordinated gene expression within functional categories, and Uniform Manifold Approximation and Projection (UMAP) showed distinct grouping of cytokine responses by virus and function. These findings describe differential immune mRNA expression profiles in response to viral stimuli in older adults and may support future studies aimed at understanding age-related differences in host–virus interactions. Full article

SARS-CoV-2, the causative virus of the COVID-19 pandemic, is a highly transmissible, enveloped, single-stranded RNA virus that has mutated into several variants, complicating vaccine strategies and drug resistance. Novel treatment modalities targeting conserved structural vulnerable points are essential to combat these variants. The primary aim of the current study is to test the mechanical vulnerability of the SARS-CoV-2 virus envelope and spike proteins to focused, high-frequency ultrasound waves (25 MHz) in vitro. Utilizing a preliminary pretest and posttest study design, the study was conducted on a virus sample within a distilled water matrix, under controlled laboratory biosafety conditions. Since detailed imaging tools were unavailable, viral disruption was indirectly measured using real-time PCR cycle threshold (Ct) values. Ct values increased significantly after high-frequency ultrasound exposure, indicating a reduction in amplifiable viral genomic material. A paired t-test indicated a significant difference between the pretest and posttest Ct (p < 0.001), which is supported by Monte Carlo test results that revealed statistically significant shifting in viral load categories (p = 0.001, two-sided). Specifically, 85.7% of high-viral-load samples converted to low or moderate content, 46.7% of low or moderate samples were shifted to negative content. This intervention produced a large effect size (Cohen’s d = 2.422). These results indicate that ultrasound may offer a promising non-pharmacological approach to destroy or inactivate SARS-CoV-2 variants in an aqueous environment. Full article

Senecavirus A (SVA) is an emerging pathogen that poses a significant threat to the global swine industry. With the advent of SVA vaccines, there is a growing need to develop serological diagnostic methods for evaluating vaccine-induced immunity. This study successfully established an indirect enzyme-linked immunosorbent assay (iELISA) through heterologous expression of a novel VP2-VP3-VP1 tandem recombinant protein in Escherichia coli (E. coli), which was constructed by integrating B-cell epitopes from VP1, VP2, and VP3. Comparative analysis using indirect ELISA revealed that the tandem recombinant VP2-VP3-VP1 protein and VP2 exhibited superior immunoreactivity. Consequently, the iELISAs for the tandem protein and VP2 were selected for further validation. Following optimization, the cut-off for the rVP2-VP3-VP1 iELISA was set at a sample-to-positive (S/P) ratio ≥ 0.60, while that for the rVP2 iELISA was set at ≥0.53. Analysis of kinetic sera from inactivated vaccine-immunized pigs showed that the rVP2-VP3-VP1 iELISA detected seroconversion synchronously with neutralizing antibodies, earlier than anti-VP2 antibodies. Finally, a serological survey for SVA was conducted in parts of mainland China from 2023 to 2024, with the rVP2-VP3-VP1 iELISA revealing an overall seroprevalence of 20.8%. These results indicate that the established detection method can be effectively used to evaluate SVA immunity and for epidemic surveillance. Full article

Introduction: Mpox virus (MpoxV), an emerging zoonotic pathogen, has recently caused global concern due to increasing outbreaks beyond its traditional endemic regions. While transmission primarily occurs via close contact, fomites are also suspected of contributing. This study aims to evaluate the effectiveness of UV-C irradiation on MpoxV-contaminated surfaces. Methods: the virucidal activity of UV-C (254 nm) irradiation on MpoxV applied to plastic, glass, and stainless-steel surfaces was assessed. Using a viral stock of 2.49 × 10⁵ TCID₅₀/mL, the samples were exposed to increasing UV-C doses. Viral titers were quantified through TCID₅₀ and plaque assays. Results: A UV-C dose of 6.34 mJ/cm² achieved a >2-log reduction of viral load, below the detection limit (31.6 TCID50/mL), on all tested surfaces. EC₉₀ values were determined as 3.33 mJ/cm² (plastic), 0.81 mJ/cm² (stainless steel), and 1.98 mJ/cm² (glass). No viable virus was detectable post-treatment at these doses on plastic and stainless steel while the titer was significantly reduced on glass. Conclusions: UV-C irradiation at low doses effectively inactivated MpoxV on various fomites. These findings support UV-C as a rapid and effective environmental disinfection strategy in healthcare and community settings to prevent indirect transmission of MpoxV. Full article

Frozen vegetables are increasingly valued for their nutritional stability and year-round availability. This study provides a comprehensive assessment of twenty commercially available frozen vegetable blends obtained from retail markets in Poland. Analyses included physicochemical parameters, instrumental measurements of texture, color (CIEL*a*b*), and evaluation of technological quality. The pH values ranged from 4.40 to 7.46, total acidity from 0.034 to 0.322 g/100 g, and dry matter content from 5.02 to 42.97%. The observed variability was mainly attributable to vegetable type and remained consistent with values reported for fresh produce, indicating that industrial freezing largely preserves chemical characteristics. Texture differed markedly between vegetable types, with hardness values ranging from 6 to nearly 100 N, while color parameters remained within typical ranges for blanched and frozen vegetables, suggesting effective pigment stability and enzyme inactivation. In contrast, substantial variability was observed in technological quality. Mechanical fragmentation exceeded acceptable limits in 30% of samples, and complete clumping of vegetable pieces (100%) was observed. Additional defects included frostbite and color deviations, and health-condition defects were observed. These results highlight considerable heterogeneity in frozen vegetable blends and emphasize the need for stricter control of raw materials, processing conditions, and cold-chain management to ensure consistent quality and consumer safety. Full article

Biocontainment laboratories often have limited access to a range of instruments required for conducting standard assays on infected materials. Consequently, some of the protocols involving infected samples are conducted outside a biocontainment facility. To be compliant with regulatory requirements and minimize health and safety risks for scientific personnel, it is imperative to test procedures rigorously for safely removing infected samples from biocontainment areas. This study validated the chemical inactivation of Nipah virus (NiV), a representative member of the Henipavirus genus, in animal tissues and serum. Importantly, this work demonstrated successful NiV-spiking of non-human primate (NHP) tissues and their subsequent inactivation. This is important because NHP tissues contain unpredictable amounts of infectious virus. The primary objective was to establish standardized protocols that are compliant with regulations to permit safe retrieval of infected biological samples with high NiV infectious virus content from ABSL-4 laboratories for subsequent downstream processing under lower biocontainment conditions. Full article

Titanium dioxide (TiO₂) thin films were deposited by DC magnetron sputtering and subsequently treated in hot water at 50, 70, and 95 °C for 72 h to investigate the influence of low temperature on their structural optical and functional properties. XRD analysis revealed a progressive transformation from amorphous to anatase phase with increasing treatment temperature, accompanied by an increase in crystallite size from 5.2 to 15.1 nm. FT-IR spectroscopy confirmed enhanced surface hydroxylation and contact angle measurements showed a decrease from 77.4° to 19.7°, indicating a significant improvement in superior wettability. The transmittance spectroscopy revealed a slight narrowing of the optical band gap from 3.34 to 3.21 eV, consistent with improved visible-light absorption. Photocatalytic tests using the Resazurin indicator demonstrated that the film treated at 95 °C exhibited the highest activity, achieving a bleaching time of 245 s three times faster than treated at 50 °C and twice as fast as treated at 70 °C. Under low-intensity solar irradiation, the same sample achieved complete E. coli inactivation within 90 min. These improvements are attributed to increased crystallinity, surface hydroxyl density, and enhanced ROS generation. Overall, this study demonstrates that mild hot-water treatment is an effective, substrate-friendly route to enhance TiO₂ film wettability and multifunctional performance, enabling the fabrication of self-cleaning and antibacterial coatings on fragile materials such as plastics and textiles. Full article