Search Results (1,917)

This study aimed to characterize Mycoplasmosis bovis strain 16M—a highly virulent isolate from one Chinese outbreak—as a candidate for challenge models and inactivated vaccine development. We assessed strain 16M through morphological observation, PCR identification, drug susceptibility testing, growth titer and biofilm quantification, immunological profiling, and calf challenge experiments. We used genomic resequencing to evaluate the genetic stability across 150 passages. Classified as the prevalent ST52 lineage in China, strain 16M showed phylogenetic proximity to strain 08M and exhibited multidrug resistance (notably to macrolides). It achieved higher titers and stronger biofilm formation than other isolates and the reference strain PG45. In calves, intratracheal inoculation with 16M induced universal infection, severe pulmonary consolidation, and peribronchial cuffing, with significantly higher disease scores (p < 0.01). The inactivated 16M vaccine elicited elevated antigen-specific IgG titers, PBMC proliferation, and IFN-γ production versus PG45. Post challenge, immunized calves showed reduced pathological lesions, shorter bacterial shedding, and lower disease scores than the infected controls (p < 0.05). Genetic stability was confirmed for virulence-associated genes (e.g., adhesion proteins), with stable titers and biofilm production within 50 generations. Strain 16M combines high virulence for challenge modeling and industrial-scale vaccine suitability, owing to its robust growth, stable immunogenicity, and genetic consistency. Full article

The transmission of Escherichia coli through contaminated fruits and vegetables poses serious public health risks and has led to several national outbreaks in the USA. To enhance food safety, rapid and reliable detection of E. coli on produce is essential. This study evaluated the performance of the CSI-D+ system combined with deep learning for detecting varying concentrations of E. coli on citrus and spinach leaves. Eight levels of E. coli contamination, ranging from 0 to 10⁸ colony-forming units (CFU)/mL, were inoculated onto the leaf surfaces. For each concentration level, 10 droplets were applied to 8 citrus and 12 spinach leaf samples (2 cm in diameter), and fluorescence images were captured. The images were then subdivided into quadrants, and several post-processing operations were applied to generate the final dataset, ensuring that each sample contained at least 2–3 droplets. Using this dataset, multiple deep learning (DL) models, including EfficientNetB7, ConvNeXtBase, and five YOLO11 variants (n, s, m, l, x), were trained to classify E. coli concentration levels. Additionally, Eigen-CAM heatmaps were used to visualize the spatial responses of the models to bacterial presence. All YOLO11 models outperformed EfficientNetB7 and ConvNeXtBase. In particular, YOLO11s-cls was identified as the best-performing model, achieving average validation accuracies of 88.43% (citrus) and 92.03% (spinach), and average test accuracies of 85.93% (citrus) and 92.00% (spinach) at a 0.5 confidence threshold. This model demonstrated an inference speed of 0.011 s per image with a size of 11 MB. These findings indicate that fluorescence-based imaging combined with deep learning for rapid E. coli detection could support timely interventions to prevent contaminated produce from reaching consumers. Full article

Cold stress adversely affects crop growth, and climate change is increasing its severity and frequency in many agricultural regions. Tomato plants are sensitive to low temperatures, although they activate some stress response mechanisms. Beneficial microorganisms can enhance cold-stress acclimation in tomato plants, but the transcriptional regulation underlying this process remains poorly understood. This study aimed to investigate the transcriptional processes activated by cold stress in tomato plants following inoculation with cold-tolerant bacteria isolated from alpine plants to identify genes potentially involved in cold stress acclimation. Among 41 cold-tolerant bacterial isolates tested, Chryseobacterium sp. GRCS301 and Pseudomonas sp. GRCS202 inoculation in sterilized soil promoted tomato growth under controlled non-stress (25 ± 2 °C) and cold-stress (10 ± 2 °C) conditions. Bacterial inoculations lowered H₂O₂ content and affected the transcriptional regulations activated in tomato shoots after one day and 14 days of incubation under cold-stress conditions. In mock-inoculated plants, cold stress downregulated genes related to energy generation, photosynthesis, and reproductive processes, highlighting its detrimental effects. Conversely, plants inoculated with Chryseobacterium and Pseudomonas upregulated genes involved in DNA replication, galactose metabolism, polysaccharide metabolism, photosynthesis, and protein metabolism in response to cold stress. Bacterial inoculation induced the expression of genes involved in reactive oxygen species homeostasis, cold-stress response, and hormonal signaling, suggesting that cold-tolerant bacteria trigger key transcriptional changes in tomato plants and enhance cold-stress acclimation. Full article

Essential oils (EOs) from oregano (Origanum vulgare), rosemary (Salvia rosmarinus), clove (Syzygium aromaticum), thyme (Thymus vulgaris), cinnamon (Cinnamomum verum), and basil (Ocimum basilicum) possess antifungal properties. This study aimed to evaluate their ability to inhibit the growth of fungi isolated from the rot of banana peel (Musa paradisiaca) to control or reduce fungal growth in bananas. The methodology involved preparing dilutions of EOs and inoculating them onto Potato Dextrose Agar (PDA) medium amended with chloramphenicol to prevent bacterial contamination. Fungal species, including Trichoderma spp., Aspergillus spp., Penicillium spp., and Fusarium spp., were isolated, purified, and characterized macroscopically and microscopically. Their growth was assessed ex vivo and the inhibition percentage was measured in vitro. The ex vivo analysis revealed that the severity of fungal infection, ranked from highest to lowest, was as follows: Penicillium spp., Trichoderma spp., Fusarium spp., and Aspergillus spp. The results showed that rosemary and basil oils did not inhibit fungal growth, whereas clove oil, cinnamon, and oregano were effective against the four tested fungi at 800, 400, and 200 ppm, respectively. These findings suggest that certain EOs, including clove, cinnamon, and oregano, have strong antifungal potential and could serve as eco-friendly alternatives to synthetic fungicides in banana postharvest disease management. Full article

This study aimed to assess whether the fertilizing effects of compost (Com) and vermicompost (VCom) applied to a preceding wheat crop, either alone or in combination with microbial biofertilizers (MBF; arbuscular mycorrhizal fungi and nitrogen-fixing bacteria), could sustain forage maize yield across contrasting soil textures. A split–split plot trial was conducted in 2023 in sandy, loamy, and clay soils. Treatments included Com, VCom, standard mineral nitrogen fertilization, and unfertilized control, each tested with or without MBF inoculation. Maize was harvested at the milk–dough stage and assessed for biomass yield, dry matter partitioning, chemical composition, and in vitro digestibility. Interactions among factors were frequent, particularly with soil texture, but overall, Com and VCom sustained biomass yield and forage quality, especially when combined with MBF. Notably, in loamy soil, VCom coupled with MBF (38.4 t ha⁻¹) outperformed mineral fertilization (32.9 t ha⁻¹). Across soils, loam produced the highest dry matter yield (27.0 t ha⁻¹) and sand the lowest (23.7 t ha⁻¹), while clay showed variable responses depending on the amendment–MBFs combination. All plots treated with the MBFconsistently exhibited higher yields compared to their respective controls, with an average increase of 52.6% across texture and fertilization strategies. Fertilization strategy and soil texture slightly yet significantly affected maize chemical composition, while digestibility remained largely preserved. Crude protein concentration peaked under mineral fertilization in loamy soil (8.3% dry matter). These findings highlight the potential of bio-based fertilizers, especially when integrated with microbial inoculants, to reduce mineral nitrogen dependency and support the sustainable intensification of forage maize. Full article

The increased consumption of ready-to-eat fruits highlights the need for better control of microbial growth during their shelf life. Among bacteria, Staphylococcus aureus and Bacillus cereus are proposed as target species for testing alternative preservative methods. This study aimed to evaluate the antimicrobial effect of the cell-free supernatant (CFS) from LAB strains previously isolated from ready-to-eat fruits, used as a mixed solution, against both reference and native S. aureus and B. cereus, which were isolated from commercial ready-to-eat fruits. A specific challenge test was conducted on minimally processed orange slices, assessing the effect of CFS on the intentionally inoculated target bacteria using a culturing and quantitative PCR (qPCR) approach. Microbiological counts varied widely among samples, indicating an initial microbiota below legislative limits, mainly comprising total mesophilic and psychrophilic bacteria, which increased significantly after 8 days of storage. Additionally, our results demonstrated the food matrix’s capacity to support the growth of both target species, with the tested CFS mainly effective in reducing the growth of reference strains. The results of the physicochemical analyses showed that during refrigerated storage, the orange slices underwent changes in pH, color, and texture, mostly in S. aureus strain-inoculated samples, negatively affecting texture at mid-storage time. The study also underscored the importance of combining plate counting with qPCR methods to detect B. cereus, as it can be risky even at low levels. Full article

Leptosphaerulina trifolii (Didymellaceae) is a widespread phytopathogen commonly associated with leaf spot diseases on legumes. However, its occurrence on Poaceae hosts has rarely been documented. In this study, leaf spot symptoms on Elymus plants were observed in Gansu and Qinghai Provinces, China. Morphological characterization, combined with multi-locus phylogenetic analyses (ITS, LSU, and RPB2) and pathogenicity assays, confirmed L. trifolii as the causal agent. Phylogenetic reconstruction demonstrated that newly obtained isolates clustered with ex-type and reference strains of L. trifolii with high support, while inoculation trials reproduced typical field symptoms and fulfilled Koch’s postulates. Growth condition assays further revealed that the fungus exhibited optimal proliferation at 20 °C, with KNO₃ and D-maltose as the most favorable nitrogen and carbon sources, respectively, and under either continuous darkness or a 12 h light/12 h dark regime. To our knowledge, this is the first report of L. trifolii causing leaf spot on Elymus spp. in China. This study provides the first evidence of L. trifolii on Elymus species, thereby expanding its known host range. Identification was confirmed through field surveys, morphological and molecular analyses, pathogenicity tests, and fungicide sensitivity, supporting the validity of this host record. Full article

Denture hygiene is crucial for preventing oral infections, with Candida albicans being a common fungal pathogen that can colonize denture surfaces. This in vitro study evaluated the adherence of C. albicans on two denture base materials—polyamide and polymethyl methacrylate (PMMA)—and assessed the antifungal efficacy of various chemical and natural cleansers. A total of 100 polished specimens were inoculated with C. albicans and treated with chemical agents (Listerine at 2%, 20%, 50%; Corega^®, Block Drug Company, Jersey City, NJ, USA); Protefix^®, Queisser Pharma, Flensburg, Germany and natural products (15% apple vinegar, 2% tea tree oil, 2% peppermint oil) for different durations (5, 15, 30, 480 min). Chlorhexidine (2%) and untreated samples served as positive and negative controls, respectively. Corega^® and 15% vinegar eliminated C. albicans within 5 min on both materials. 50% Listerine was effective after 5 min on PMMA but required 480 min on polyamide. Protefix^® showed full efficacy in 5 min on PMMA and 30 min on polyamide. Tea tree oil required 30–480 min for activity, while peppermint oil showed minimal effect throughout. Under the tested conditions, Corega^® appeared most effective. Natural cleansers, particularly vinegar and tea tree oil, also showed considerable anticandidal potential, suggesting they may serve as alternative agents for denture hygiene applications. Full article

The global sparkling wine market continues to grow steadily, reaching approximately 24 million hectoliters in 2023, with an annual increase of around 4% despite a general decline in overall alcoholic beverage consumption. This growth highlights the importance of employing diverse yeast strains to improve product variety and quality. Flor yeasts are specialized strains of Saccharomyces cerevisiae that develop a biofilm on the surface of certain wines during biological ageing. They possess unique physiological properties, including high ethanol tolerance and the capacity to adhere, which supports wine clarification. They also have the ability to contribute unique volatile compounds and aroma profiles, making them promising candidates for sparkling wine production. This study evaluated two flor yeast strains (G1 and N62), which were isolated from the Pérez Barquero winery during the second fermentation process using the traditional method. Sparkling wines were produced by inoculating base wine (BW) with each strain, and the wines were monitored at 3 bar CO₂ pressure and after 9 months of ageing on lees. Comprehensive metabolomic analysis was performed using GC-MS for volatile compounds and HPLC for nitrogen compounds, with statistical analysis including PCA, ANOVA, Fisher’s LSD, and correction FDR tests. Strain N62 demonstrated faster fermentation kinetics and higher cellular concentration, reaching 3 bar pressure in 27 days compared to 52 days for strain G1. Both strains achieved similar final pressures, 5.1–5.4 bars. Metabolomic profiling revealed significant differences in the profiles of volatile and nitrogen compounds between the two strains. G1 produced higher concentrations of 3-methyl-1-butanol, 2-methyl-1-butanol, and acetaldehyde, while N62 generated elevated levels of glycerol, ethyl esters, and amino acids, including glutamic acid, aspartic acid, and alanine. These findings demonstrate that both flor yeast strains successfully complete sparkling wine fermentation while producing distinct metabolic signatures that could contribute to unique sensory characteristics. This supports their potential as alternatives to conventional sparkling wine yeasts for enhanced product diversification. Full article

Objectives: This phase 3 clinical trial aimed to evaluate the safety and immunogenicity of the Sabin inactivated poliovirus vaccine (sIPV) manufactured by Biominhai in healthy infants following a sequential immunization regimen. Methods: A total of 300 healthy infants aged 2 months were randomly divided into the test group (sIPV-sIPV-bOPV) and the control group (wIPV-wIPV-bOPV) according to the ratio of 1:1. Both groups were inoculated under “2IPV + 1bOPV” schedule. Safety was assessed alongside poliovirus antibody levels before and after vaccination. Results: The overall incidence of adverse reactions (AEs) in the test and control groups was 44% and 39%, respectively. AEs in both groups primarily occurred following the first dose, with approximately 30% classified as grade 1 in severity. No significant differences were observed between groups regarding the incidence, severity, and symptoms of AEs. Additionally, no vaccine-related serious adverse events (SAEs) were reported. At 30 days after the last dose, the seroconversion rates of neutralizing antibodies against poliovirus types I and III reached 100% in both groups, while type II rates at 99% for the test group and 95% for the control. Notably, the seroconversion rates for all types in the test group were non-inferior to those in the control group. The geometric mean titers (GMTs) of neutralizing antibodies against poliovirus for type I (8622.64 vs. 2687.65), type II (207.73 vs. 54.06), and type III (2121.74 vs. 1699.12) were significantly higher in the test group (p < 0.0001 for type I and II; p = 0.04 for type III). Conclusions: The study concluded that the trial vaccine sIPV following sequential immunization program demonstrates good safety and immunogenicity, showing non-inferiority to the control vaccine. Full article

Progressive myopia in children is a highly prevalent condition in societies worldwide and is often treated with compounded low-dose atropine sulfate (AS) eye drops without preserving agents to avoid irritation/sensitisation. Surprisingly, there is a lack of data regarding the in-use stability of contamination-free LDPE dispenser units (CFDs) for this compounded multidose product, which causes uncertainty among prescribers and patients in Europe. Thus, our aim was to compare the effect of different dispenser types on the chemical and microbial stability of unpreserved AS eye drops (0.01% w/w). A dripping simulation was performed to obtain information on microbial stability over 4 weeks through plating and separately over 12 weeks through direct inoculation, HPLC and pH analysis. For CFDs, no contamination was found after 4, 8 or 12 weeks of use when stored at 23 or 4 °C as opposed to the control. AS content remained within 0.01 ± 0.0002% w/w after 12 weeks, with higher chemical stability at 4 °C despite decreasing pH. A stress test confirmed the validity of the CFD system. In conclusion, using CFDs and refrigerated storage was found to be safe for compounded unpreserved AS eye drops over 12 weeks of use. Full article

Background/Objectives: Maternally derived antibody (MDA) levels of porcine circovirus 2 (PCV2) may eventually interfere with humoral response and vaccination efficacy. This study aimed to evaluate the efficacy of a ready-to-use PCV2d and Mycoplasma hyopneumoniae combined vaccine in piglets with different PCV2 MDA levels at vaccination in an experimental inoculation with a heterologous viral genotype. Methods: Forty-eight piglets were allocated into vaccinated (V) and non-vaccinated (NV) groups with high (H) and low (L) PCV2 MDA subgroups (H-V, H-NV, L-V, L-NV). At 3 weeks of age, the piglets received either one dose of vaccine or placebo. Five weeks later, all animals were intranasally challenged with a PCV2b inoculum. Body weight was registered at different time points. Blood samples, peripheral blood mononuclear cells and tracheobronchial lymph nodes (TBLN) were collected and used to assess viraemia, viral load, humoral and cellular responses and histological lesions. Results: The V group showed higher PCV2 antibody levels from challenge onwards, along with a lower percentage of viraemic pigs and reduced viral load in serum at 2 and 3 weeks post-challenge (wpc) and in TBLN tissues compared to the NV group. The H-V group had the highest antibody levels post-challenge, showed no detectable viraemia and had a lower overall amount of virus in tissues. The NV group (especially H-NV) exhibited increased levels of IFN-γ, IFN-α and TNF-α post-challenge. Conclusions: The tested vaccine elicited humoral and cellular immune responses and reduced viral presence in serum and tissues, demonstrating efficacy in a PCV2 subclinical infection model despite high MDA levels at the time of vaccination. Understanding both humoral and cellular immune responses according to different MDA levels can help design more effective vaccination strategies against PCV2. Full article

Despite the devastating consequences of fungal disease, research struggles to catch up to present needs. This study aims to give a broad perspective on the situation, investigating patterns and distribution of fungal pathogens and monitoring trends of resistance to antifungal drugs, over an 8-year timeframe, at the National Institute of Infectious Diseases “Prof. Dr. Matei Balș” in Bucharest, Romania. Samples were inoculated on Sabouraud or Brilliance Candida Agar media; strains were identified using MALDI-TOF MS; and antifungal sensitivity testing was performed using E-Tests strips, VITEK2 Compact and MICRONAUT-AM automatic systems. Candida albicans, accounting for 42% of the positive samples, was the most common pathogen observed, with only 17% of the isolates being susceptible to all antifungals tested, while it was also predominant and deadly in the ICU. The emerging Candidozyma auris, found in 8% of the candidoses, exhibited a fluconazole resistance rate of 96.3%. Of the Aspergillus fumigatus strains, 35.7% showed resistance to azoles, and 25% to amphotericin B. In the ICU, more than half of A. flavus-, A. fumigatus- or A. niger-related cases culminated in death. Antifungal resistance is not to be treated lightly, as it is still a complex and dynamic threat, with devastating consequences. Full article

This study aimed to evaluate the effectiveness of combining load–close–homogenize (LCH), test and removal (T&R), and rollover strategies for PRRSV elimination in breeding herds using PRRSV-positive weaned gilts. Here, a novel strategy was explored for PRRSV elimination from more than 1500 weaned gilts, and we documented the process from PRRSV natural infection to elimination at the herd level. With LCH implementation, the herd achieved PRRSV-positive stability within 8 months. Consequently, by rolling in self-breeding PRRSV-naive gilts to replace PRRSV-positive weaned sows batch by batch, the time from being positive stable to negative was 13 months. A PRRSV-positive farm intending to retain its genes in its repopulate farrow to become a finished breeding farm can initiate PRRSV elimination from its weaned gilts; this will result in the first farrowing batch of piglets aged 8–10 weeks becoming PRRSV-negative after 8 months of herd closure. This approach offers a viable pathway for genetic retention and PRRSV elimination in breeding farms. Full article

Fire blight, caused by Erwinia amylovora, is a severe disease impacting pome fruit production worldwide, including in Saudi Arabia. This study evaluated antibiotic sensitivity and the potential of chemical and elicitor treatments to suppress E. amylovora isolates collected from various regions in Saudi Arabia. In the in vitro assays, at low antibiotic levels (10 µg/mL streptomycin and 25 µg/mL oxytetracycline), all Saudi Arabian strains exhibited minimal inhibition (zones ≤ 14 mm). Two isolates displayed partial tolerance at an intermediate oxytetracycline concentration (50 µg/mL). True sensitivity (zones > 18 mm) was mainly observed at the highest tested oxytetracycline dose (100 µg/mL). Regarding copper sulfate, all isolates showed no inhibition between 0.02 and 0.08 mM, while all isolates exhibited intermediate susceptibility at 0.16 mM. The second experimental phase examined in planta effects of streptomycin, salicylic acid (SA), and their combination on disease development in artificially inoculated apple (Malus domestica) shoots under greenhouse conditions. Both streptomycin and SA significantly reduced fire blight incidence (by 75%) and symptom severity, while the combined treatment yielded the greatest reduction in shoot necrosis and bacterial load. This is the first report demonstrating that SA, particularly when used in combination with streptomycin, can effectively suppress fire blight in Saudi Arabia. These results stress the importance of integrating resistance inducers into fire blight management strategies to counter the rise in antimicrobial resistance. Full article