Search Results (362)

The “milky disease” in Chinese mitten crabs (Eriocheir sinensis), caused by Metschnikowia bicuspidata, poses significant threats to aquaculture, though its pathogenic mechanisms remain poorly understood. This study employs transcriptomic sequencing to analyze gene expression changes in Metschnikowia bicuspidata under hemocyte challenge, iron overload (1 mmol/mL), and combined stress, with functional validation through Common in Fungal Extracellular Membrane (CFEMgene) overexpression strains. Key findings reveal that (1) hemocyte challenge activated base excision repair (−log₁₀[P] = 7.58) and ribosome biogenesis pathways, indicating fungal adaptation through DNA repair and enhanced protein synthesis to counter host immune attacks (e.g., ROS-mediated damage). (2) Iron overload induced glutathione metabolism and pentose phosphate pathway enrichment, demonstrating mitigation of ferroptosis through NADPH/GSH antioxidant systems and autophagy/proteasome coordination. (3) Under combined stress, ribosome biogenesis (−log₁₀[P] = 1.3) and non-homologous end-joining pathways coordinated DNA repair with stress protein synthesis, complemented by vacuolar V-ATPase-mediated iron compartmentalization. (4) CFEM genes showed significant upregulation under hemocyte stress, with overexpression strains exhibiting enhanced biofilm formation (35% increased MTT cytotoxicity) and infectivity (40% higher infection rate), confirming CFEM domains mediate pathogenesis through iron homeostasis and virulence factor production. This work elucidates how M. bicuspidata employs metabolic reprogramming, oxidative stress responses, and CFEM-mediated iron regulation to establish infection, providing critical insights for developing targeted control strategies against milky disease. Full article

Classical epidemic models treat vaccine uptake as an exogenous parameter, yet real-world coverage emerges from strategic choices made by individuals facing uncertain risks. During the last two decades, vaccination games, which combine epidemic dynamics with game theory, behavioural economics, and network science, have become a very important tool for analysing this problem. Here, we synthesise more than 80 theoretical, computational, and empirical studies to clarify how population structure, psychological perception, pathogen complexity, and policy incentives interact to determine vaccination equilibria and epidemic outcomes. Papers are organised along five methodological axes: (i) population topology (well-mixed, static and evolving networks, multilayer systems); (ii) decision heuristics (risk assessment, imitation, prospect theory, memory); (iii) additional processes (information diffusion, non-pharmacological interventions, treatment, quarantine); (iv) policy levers (subsidies, penalties, mandates, communication); and (v) pathogen complexity (multi-strain, zoonotic reservoirs). Common findings across these studies are that voluntary vaccination is almost always sub-optimal; feedback between incidence and behaviour can generate oscillatory outbreaks; local network correlations amplify free-riding but enable cost-effective targeted mandates; psychological distortions such as probability weighting and omission bias materially shift equilibria; and mixed interventions (e.g., quarantine + vaccination) create dual dilemmas that may offset one another. Moreover, empirical work surveys, laboratory games, and field data confirm peer influence and prosocial motives, yet comprehensive model validation remains rare. Bridging the gap between stylised theory and operational policy will require data-driven calibration, scalable multilayer solvers, and explicit modelling of economic and psychological heterogeneity. This review offers a structured roadmap for future research on adaptive vaccination strategies in an increasingly connected and information-rich world. Full article

The escalating threat of infectious diseases necessitates the development of diagnostic technologies that are not only rapid and sensitive but also deployable at the point of care. Electrochemical impedance spectroscopy (EIS) has emerged as a leading technique for the label-free detection of pathogens, offering a unique combination of sensitivity, non-invasiveness, and adaptability. This review provides a comprehensive overview of the design and application of EIS-based biosensors tailored for pathogen detection, focusing on critical components such as biorecognition elements, electrode materials, nanomaterial integration, and surface immobilization strategies. Special emphasis is placed on the mechanisms of signal generation under Faradaic and non-Faradaic modes and how these underpin performance characteristics such as the limit of detection, specificity, and response time. The application spectrum spans bacterial, viral, fungal, and parasitic pathogens, with case studies highlighting detection in complex matrices such as blood, saliva, food, and environmental water. Furthermore, integration with microfluidics and point-of-care systems is explored as a pathway toward real-world deployment. Emerging strategies for multiplexed detection and the utilization of novel nanomaterials underscore the dynamic evolution of the field. Key challenges—including non-specific binding, matrix effects, the inherently low ΔR_ct/decade sensitivity of impedance transduction, and long-term stability—are critically evaluated alongside recent breakthroughs. This synthesis aims to support the future development of robust, scalable, and user-friendly EIS-based pathogen biosensors with the potential to transform diagnostics across healthcare, food safety, and environmental monitoring. Full article

Genetic resistance is a sustainable way to protect crops from diseases, and breeding resistant varieties is a key objective. However, diseases are caused by pathogens with different life cycles, and the importance of individual evolutionary forces plays a key role in the adaptation of their populations. Therefore, strategies for the use of genetic resistance resources can vary depending on the plant pathosystem. Numerous major genes confer hypersensitive resistance to powdery mildew—one of the most common diseases in barley—but these genes conform to the gene-for-gene system of an extremely diverse and adaptable pathogen. When such resistance genes are transferred into commercial varieties, their efficiency in the field is soon overcome and replacement with newly developed resistant varieties can be slow. Hence, specific resistance genes should not be used in barley breeding programs. Only one monogenic, non-hypersensitive, non-specific and durable major resistance Mlo is known. This predominates in Central and Western European spring varieties and should be widely adopted by barley breeders elsewhere and in other crops where such type of resistance is found. In this paper, the relevant aspects involved in breeding barley resistant to powdery mildew are discussed, with conclusions supported by practical examples. Additionally, future directions for barley improvement are proposed. Full article

Rice is a staple food for over half of the world’s population, and it is grown in over 100 countries. Rice blast disease can cause 10% to 30% crop loss, enough to feed 60 million people. Breeding for resistance can help farmers avoid costly fungicides. This study assessed the relationship between rice blast disease and zinc or anthocyanin content in biofortified rice. Susceptibility to foliar and panicle blast was assessed in a rice panel which differed on grain zinc content and pigmentation. A rice panel (n = 23) was challenged with inoculum of two isolates of Magnaporthe oryzae in a screenhouse-based assay. The zinc content with foliar blast severity was analyzed in the leaves and grain of a subset of non-inoculated rice plants. The effect of foliar zinc supplementation on seedlings was assessed by varying levels of zinc fertilizer solution on four blast susceptible cultivars at 14 days after planting (DAP), followed by inoculation with the blast pathogen at 21 DAP. Foliar blast severity was scored on a 0–9 scale at 7 days after inoculation. The rice panel was scored for anthocyanin content, and the data were correlated with foliar blast severity. The panel was grown in the field, and panicle blast, grain yield and yield-related agronomic traits were measured. Significant differences were observed in foliar blast severity among the rice genotypes, with IRBLK-KA and IR96248-16-2-3-3-B having mean scores greater than 4, as well as BASMATI 370 (a popular aromatic variety), while the rest of the genotypes were resistant. Supplementation with foliar zinc led to a significant decrease in susceptibility. A positive correlation was observed between foliar and panicle blast. The Zn in the leaves was negatively correlated with foliar blast severity, and had a marginally positive correlation with panicle blast. There was no relationship between foliar blast severity and anthocyanin content. Grain yield had a negative correlation with panicle blast, but no correlation was observed between Zn in the grain and grain yield. This study shows that Zn biofortification in the grain may not enhance resistance to foliar and panicle blast. Furthermore, the zinc-biofortified genotypes were not agronomically superior to the contemporary rice varieties. There is a need to apply genomic selection to combine promising alleles into adapted rice genetic backgrounds. Full article

Listeria monocytogenes poses significant risks in acidic foods like unpasteurized fruit juices due to its capacity to survive under stressful conditions. This study evaluated L. monocytogenes survival in orange juice following acid adaptation and exposure to antimicrobial compounds. Acid adaptation was induced using glucose-supplemented or citric acid-acidified media, followed by the evaluation of pathogen survival in orange juice stored at 4 °C, 15 °C, and 25 °C. While glucose adaptation reduced the medium pH to 4.5 and enabled bacterial growth (up to 7.5 total log CFU/mL), citric acid exposure caused around 1.4 log units of reduction. Contrary to expectations, the survival of acid-adapted cells was lower than that of non-acid-adapted cells, particularly in orange juice stored at 25 °C (around 4.8 vs. 1.4 log units of reduction after 6 days). The behaviour of non-acid-adapted cells was evaluated in response to different antimicrobial compounds (citral, coumaric acid, nisin, sinapic acid, and vanillin). Nisin was the most effective, achieving a reduction of about 3.5 log units with a dose of 2 mL/L. Nisin-treated cells also showed reduced survival during simulated gastrointestinal assays (around 1.5 log units of reduction). These results challenge the assumption that acid adaptation universally enhances survival in acidic matrices and highlight nisin’s dual role in microbial control and pathogenicity mitigation. This work underscores the need for tailored stress adaptation studies and natural antimicrobial applications to improve food safety in minimally processed fruit juices. Full article

Bloodstream infections (BSIs) are a major cause of morbidity and mortality in acute myeloid leukemia (AML) patients undergoing induction chemotherapy. Staphylococcus epidermidis, typically a skin commensal, is increasingly recognized as a pathogen in these vulnerable individuals. This study investigated whether genomic differences exist between infectious and gastrointestinal colonizing S. epidermidis isolates from AML patients and how these compare to colonizing and infectious isolates from other patient groups and biogeographic sites. We analyzed 114 isolates—44 from AML patients (23 infections, 21 GI colonizers) and 70 from public datasets (34 infections, 36 colonizers). Stool samples underwent 16S rRNA sequencing and culture to identify colonization, while bloodstream isolates were sequenced and compared. Genomic profiling using Roary, Scoary, Phyre2, and InterProScan revealed that infectious and GI-colonizing AML isolates were phylogenetically close but genomically distinct. Infectious isolates from AML patients were significantly enriched for resistance genes (e.g., mecA, mecR1, mecI, ANT(4′)-Ib) and the biofilm-associated gene icaA. AML infectious isolates harbored more resistance genes and mobile elements than non-AML strains but lacked widespread classical virulence factors. These results suggest that S. epidermidis pathogenicity in immunocompromised hosts is driven by genomic adaptability and antibiotic tolerance rather than traditional virulence mechanisms. Full article

Stress granules (SG), dynamic cytoplasmic condensates formed via liquid-liquid phase separation (LLPS), serve as a critical hub for cellular stress adaptation and antiviral defense. By halting non-essential translation and sequestering viral RNA, SG restrict viral replication through multiple mechanisms, including PKR-eIF2α signaling, recruitment of antiviral proteins, and spatial isolation of viral components. However, viruses have evolved sophisticated strategies to subvert SG-mediated defenses, including proteolytic cleavage of SG nucleators, sequestration of core proteins into viral replication complexes, and modulation of stress-responsive pathways. This review highlights the dual roles of SG as both antiviral sentinels and targets of viral manipulation, emphasizing their interplay with innate immunity, autophagy, and apoptosis. Furthermore, viruses exploit SG heterogeneity and crosstalk with RNA granules like processing bodies (P-bodies, PB) to evade host defenses, while viral inclusion bodies (IBs) recruit SG components to create proviral microenvironments. Future research directions include elucidating spatiotemporal SG dynamics in vivo, dissecting compositional heterogeneity, and leveraging advanced technologies to unravel context-specific host-pathogen conflicts. This review about viruses and SG formation helps better understand the virus-host interaction and game process to develop new drug targets. Understanding these mechanisms not only advances virology but also informs innovative strategies to address immune escape mechanisms in viral infections. Full article

The World Health Organization (WHO) cites antimicrobial resistance as among the greatest threats to human health. The multidrug-resistant pathogen Acinetobacter baumannii, recognized as a priority pathogen for healthcare and research, is responsible for a diverse array of infections including respiratory tract, soft tissue and wound, and bloodstream infections. Despite this importance, the mechanisms of its pathogenesis remain poorly understood. Conjugation represents a central mechanism for bacterial adaptation and evolution and is responsible for the spread of genes that promote pathogen survival, antibiotic resistance, virulence, and biofilm formation. Our laboratory recently characterized a large group of almost 120 Type IV Secretion System (T4SS)-encoding plasmids in Acinetobacter, distributed globally across 20 countries spanning four continents, and demonstrated that an XDR A. baumannii plasmid from this family was transmissible to another A. baumannii strain. This research investigated the potential diversity of host strains for this representative member plasmid. Using the GC1 lineage strain A. baumannii AB5075-UW harbouring the XDR plasmid p1AB5075 and a series of previously characterized clinical and environmental Acinetobacter strains, conjugative analyses demonstrated transfer of the XDR plasmid to both A. baumannii strains of more genetically divergent sequence types and to non-baumannii Acinetobacter species both inside and outside the Acinetobacter calcoaceticus–baumannii (ACB) complex. Successful recipients included diverse strains of both clinical and environmental origin within the Acinetobacter genus. Collectively, this research could provide insights into an important genetic element for future surveillance. Full article

Background/Objectives: Recurring infections in children with allergies pose significant clinical challenges, with these conditions often exacerbating each other through complex immunological interactions. This narrative review examines the connection between recurring infections and allergic conditions in pediatric patients, focusing on how immune system dysfunction influences infection susceptibility in respiratory allergies. Methods: A comprehensive literature search across PubMed, Web of Science, and SciELO databases was conducted from January 2014 to May 2024. Studies involving children and adolescents up to 18 years old with diagnosed respiratory allergies were included, while reviews, opinion pieces, case reports, and studies not addressing immune–infection interactions were excluded. Results: Analysis reveals significant immune dysfunction in allergic children, affecting both innate and adaptive immunity components. Children with allergic rhinitis and asthma demonstrate decreased interferon-gamma production, increasing vulnerability to viral infections (particularly rhinovirus) and bacterial infections such as Mycoplasma pneumoniae. Rhinovirus represents the most common pathogen, present in 75% of asthma exacerbations. Atopic children exhibit markedly higher bacterial infection rates, with 27.1% showing Mycoplasma pneumoniae involvement versus 4.9% in non-atopic children. Conclusions: Recurring infections in allergic pediatric patients result from significant immune dysfunction involving altered cytokine production and immune cell function. These complex interactions highlight the need for targeted therapeutic approaches that enhance immune responses and reduce infection risks. Future research should focus on identifying specific biomarkers and immune mechanisms for developing more effective interventions. Full article

The health benefits associated with microbial species inhabiting aquatic animals have garnered increasing attention, as it is expected that the colonization and efficacy of native probiotic bacteria adapted to the internal environment of the target species will be more active than non-native bacteria. In this study, six isolates were obtained from the intestinal tract of largemouth bass. Three of these isolates demonstrated higher growth ability compared to the others and were further characterized using in vitro assays. Lactococcus lactis LBM15 was found to exhibit antibacterial activity against common pathogens affecting largemouth bass; the adhesion inhibition capabilities of the isolates were systematically evaluated through competitive, repulsive, and substitutive adhesion assays. The strain inhibited adhesion to all six tested pathogen strains, with competitive adhesion inhibition rates ranging from 42% to 54%, the highest of which was observed against V. anguillarum. Repulsive adhesion inhibition rates ranged from 27% to 55%, with the highest rate noted for Edwardsiella tarda. Additionally, substitutive adhesion inhibition rates were found to range from 48% to 76%, with the highest inhibition observed against Aeromonas hydrophila. Furthermore, LBM15 exhibited favorable antimicrobial susceptibility profiles, showing sensitivity to 21 antibiotics tested. Notably, safety assessment trials were performed exposing fish to LBM15 at a concentration of 1 × 10⁹ CFU/mL by injection and at a concentration of 1 × 10⁸ CFU/mL by feed administration. No clinical abnormalities, behavioral alterations, or mortality were documented in either exposure group, confirming the safety of LBM15 for application in aquaculture. The results suggested that LBM15 isolates from largemouth bass have potential for further investigation and possible application as probiotic candidates. Full article

Rhizospheric fungi are emerging as a critical research component in dragon fruit (Hylocereus spp.) production systems. Introducing beneficial non-native fungi is increasingly common due to their positive effects on plant growth, yield, and pathogen suppression. However, this practice may disrupt soil microbial communities, and commercial isolates often show limited adaptation to local conditions. This study aimed to identify native beneficial soil fungi associated with dragon fruit cultivation on the Ecuadorian coast and evaluate their effect on commercial production. Fungal isolates from four dragon fruit plantations were identified using microscopy and genetic sequencing (ITS, EF-1α, and beta-tubulin). The selected fungi were isolates closely related to Talaromyces tumuli, Trichoderma asperellum, and Paecilomyces lagunculariae. All isolates were tested for pathogenicity using detached cladode assays at the laboratory, and non-phytopathogenic monomorphic cultures were further evaluated in the field under a randomized complete block design consisting of T. asperellum, Talaromyces tumuli, a combination of both, and a water control. The combination of T. asperellum and Talaromyces spp. showed a favorable trend in terms of the plants’ vegetative development. However, inoculating Talaromyces tumuli into the commercial plants exhibited a slow response during the first 20 days of the field evaluations. Still, it resulted in a significant increase in the fruit’s diameter and weight, with increases of 88.23% and 67.64%, respectively, compared to those in the control. T. asperellum presented a lower number of fruits per plant, although it showed an increase in fruit diameter and weight. In conclusion, using the native beneficial fungi T. asperellum and T. tumuli contributes positively to the dragon fruit production system. Full article

Leucaena leucocephala (Lam.) de Wit is listed in the world’s 100 worst alien invasive species because of the risks it poses to native plant communities. Life history traits, such as high growth and reproductive rates, and a high capacity to adapt to different environmental conditions may contribute to its invasive properties. Biotic stressors, such as herbivores, pathogens, and competing plant species are known to exert significant selective pressure on the plant’s survival, distribution, and abundance. L. leucocephala has been reported to contain several compounds involved in the defense functions against these biotic stressors. A large amount of L-mimosine, a non-protein amino acid, was found in all plant parts of L. leucocephala, including its flowers. L-Mimosine is toxic to herbivorous mammals and insects, parasitic nematodes, pathogenic fungi, and neighboring competing plant species by inactivating various essential enzymes and blocking DNA replication, and/or inducing oxidative stress conditions. Several flavonoids, polyphenolic compounds, and/or derivatives of benzoic and cinnamic acids are toxic to parasitic nematodes, pathogenic fungi and bacteria, and competing plant species by disrupting plasma membrane structures and functions, and various metabolic processes. These compounds may represent the invasive traits of L. leucocephala that have undergone natural selection during the evolution of the species. They may contribute to the defense functions against the biotic stressors, and increase its survival, distribution, and abundance in the introduced ranges. This is the first review to focus on the compounds involved in the defense functions against biotic stressors. Full article

Understanding the interplay between antifungal resistance, stress adaptation, and virulence in Aspergillus fumigatus is critical for more effective treatment outcomes. In this study, we investigate six clinical isolates of A. fumigatus from the hospitals of the Czech Republic, focusing on their resistance profiles, stress responses, and survival mechanisms under antifungal pressure. Notably, we have shown that azole-susceptible strains were able to form persister cells under supra-MIC concentrations, highlighting an emerging non-genetic survival mechanism. Stress response profiling demonstrated differential susceptibility to agents targeting signal transduction pathways, as principal component analysis proved that even azole-resistant strains might rely on these pathways. Combinatorial treatment with posaconazole and dithiothreitol enhanced antifungal efficacy regardless of the susceptibility of the strains. Fitness assays revealed that azole resistance imposed a competitive disadvantage in azole-free conditions. In vivo virulence assessment in Galleria mellonella larvae revealed strain-specific pathogenicity that did not directly correlate with resistance. Together, our findings illustrate the multifactorial nature of fungal survival and emphasize that stress adaptation, tolerance, and persistence significantly affect treatment efficacy and outcomes, even in the absence of classical resistance mechanisms. Targeting stress response pathways emerges as a promising strategy to enhance the efficacy of existing antifungal agents and manage resistance in A. fumigatus. Full article

Mastitis is defined as mammary gland inflammation and is one of the most common and economically significant diseases affecting dairy cows. Bacteria are the most frequently reported agents responsible for mastitis, while other pathogens are often overlooked due to insufficient routine investigation. Incomplete diagnoses can result in inappropriate antimicrobial treatments, treatment failures, antimicrobial resistance, the spread of pathogens, and the recurrence of mastitis. Background/Objectives: This study aimed to investigate the presence of Staphylococcus spp. associated with Romanian buffalo mastitis on dairy farms in Western Romania via a bacteriological analysis of mastitis milk and determine antimicrobial susceptibility profiles. Methods: Bacterial culture was performed according to the guidelines described by the National Mastitis Council. Vitek 2 Compact systems (Bio Mérieux, France), with the GP ID cards, were used to confirm the species of the isolates. Antibiotic susceptibility testing was conducted by utilizing Vitek^® 2 preset antimicrobial card AST-GP79 Gram-positive Livestock WW. Results: Of all the milk samples (n = 115) analyzed, 83 were positive for Staphylococcus spp. (72.17%) and were evaluated for their antimicrobial susceptibility profiles. The most common microorganism found was S. aureus (n = 46; 55.42%), followed by S. hyicus (n = 28; 33.73%) and S. schleiferi (n = 9; 10.84%). These pathogens demonstrated significant resistance to the tetracycline, neomycin, benzylpenicillin, and erythromycin. Conclusions: Current control measures for mastitis caused by S. aureus are ineffective. A better understanding of the virulence factors in Romanian buffalo-adapted strains of S. aureus, their pathogenesis, and host immunological responses is essential for developing effective and sustainable non-antibiotic control tools such as vaccines, prophylactic therapies, and other innovative approaches. Full article