Search Results (8,319)

Plasmodium knowlesi infections can progress rapidly to life-threatening complications, such as acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI), which are driven by the ability of the zoonotic parasite to rapidly replicate towards high parasitemia and the cytoadherence properties of the infected erythrocytes (IRBCs). This study evaluated the anti-parasitic and vasoprotective potential of Annona muricata (soursop) leaf ethanol extract against P. knowlesi. In vitro assays using the P. knowlesi A1-H.1 reference strain revealed significant blood stage schizogony inhibition (IC₅₀: 9.65 µg/mL), specifically targeting the trophozoites. The anti-parasitic activity was concentrated in the <30 kDa subfraction of the extract. Washout assays confirmed that the effect was parasitostatic rather than parasiticidal, where the malaria parasites underwent developmental arrest but remained morphologically normal and resumed growth post-removal. Furthermore, priming human endothelial cell lines with the extract significantly reduced IRBC–endothelial binding. These results demonstrate that A. muricata extract exerts a dual-action effect by arresting P. knowlesi asexual replication and inhibiting IRBC–endothelial cytoadherence. While clinical translation would require exhaustive standardization and chemotypic profiling due to the natural variability of plant compositions, these findings provide a foundational academic framework for the potential of A. muricata leaf extract in mitigating severe knowlesi malaria complications. Full article

Sugarcane smut is a fungal disease caused by Sporisorium scitamineum. To explore its biological control strategies, this study collected rhizosphere soil of sugarcane, isolated and identified biocontrol bacteria from it, and conducted multi-level control efficacy evaluations. The results showed that five bacterial strains with effective antagonistic activity against the sexual mating and teliospore germination of S. scitamineum were isolated and identified: 2143-2 (Pseudomonas baetica), 2143-4 (Bacillus subtilis), 2143-6 (Burkholderia diffusa), Y8-2 (Pseudomonas reinekei), and Y8-3 (Bacillus amyloliquefaciens). The results of the pot inoculation experiments showed that all five strains could prolong the incubation period of sugarcane smut and significantly reduce the disease incidence, demonstrating marked control effects, with strains 2143-4 and Y8-2 being the most effective. The results of the field inoculation experiments and natural field infection experiments indicated that strain Y8-2 exhibited the best biocontrol efficacy against sugarcane smut, with control efficacies of 68.40% and 73.99% in the field inoculation experiments, and 65.73% under natural field infection conditions. In addition, the biocontrol strains could improve the physiological stress-tolerance characteristics of sugarcane plants, which was conducive to enhancing the resistance of sugarcane plants to sugarcane smut. Full article

Haemonchus contortus is one of the most prevalent gastrointestinal nematodes in all ecosystems in Mexico, where sheep are raised on pasture, and it poses a significant threat. This study aimed to examine the surgical isolation of a Mexican H. contortus strain, its morphological and molecular characterization, and the maintenance of this strain for future research. Biological behavior and some phenotypic aspects of the adults were considered. Fecal samples were obtained from naturally infected sheep, larval cultures were performed, and a nematode-free lamb was infected. Once the infection was established, the donor sheep were euthanized, the adults recovered, and H. contortus females and males were selected. A surgical transfer from H. contortus adult to the abomasum of a receptor lamb was performed, and the beginning of the egg excretion was confirmed three days post-transfer; fecal cultures from the receptor lamb were conducted to verify the purity of the strain. After three lambs were infected with 3000, 5000, and 10,000 L3, the pre-patent period, prolificacy, and measurements of the adult stages of the strain were studied. The molecular characteristics were evaluated by qPCR; primers were designed based on NCBI genomic DNA sequences of H. contortus to amplify a 176 bp fragment, and the amplicon was sequenced for taxonomic identification. The results of this study describe biological characteristics and some phenotypic aspects of the adults, as well as eggs and infective larvae, and molecular characteristics of the isolated strain, and establish a successful methodology for isolating and maintaining a pure strain of H. contortus (FESC-strain); it can be used as a reference in experimental infections or anthelmintic resistance studies. Full article

Aging is accompanied by complex structural and functional immune system changes driven by genomic instability, epigenetic alterations, mitochondrial dysfunction, telomere attrition, loss of proteostasis, deregulated nutrient sensing, and the accumulation of senescent cells exhibiting a senescence-associated secretory phenotype, which altogether lead to severe consequences including altered antimicrobial defense, the overproduction of autoantibodies, and chronic, low-grade inflammation (inflammaging). In this article, we summarize age-related alterations in the function of primary and secondary lymphoid organs, including the bone marrow, thymus, spleen, and lymph nodes. The involution of these organs leads to impaired hematopoiesis, reduced production of naïve lymphocytes, and immune microenvironment disruption. We also describe aging-related impairment of the activity of neutrophils, macrophages, dendritic cells and natural killer cells, as well as dysregulation of T and B lymphocyte responses. Specifically, these alterations include a decline in naïve cell populations, an accumulation of memory and exhausted cells, and a reduction in the diversity of antigen receptors. Consequently, older individuals exhibit increased susceptibility to infections, cancer, and autoimmune diseases, along with diminished vaccine efficacy. Understanding the mechanisms underlying immune aging could lay the foundation for developing therapeutic strategies and lifestyle interventions to mitigate the adverse effects of this unfavorable process. Full article

Background: Diabetic foot osteomyelitis (DFO) poses significant challenges due to its high morbidity and recurring nature. Current treatments involve prolonged antibiotics and often surgical intervention; however, the optimal route of antibiotic administration is unknown. This study evaluated the effect of route of antibiotic administration on treatment failure among patients with diabetic foot osteomyelitis. Methods: The authors conducted a retrospective cohort study among patients with unresected diabetic foot osteomyelitis. A propensity score was used to match the treatment exposure groups. The primary outcome was treatment failure, defined as either (1) treatment with additional antibiotic course or (2) additional surgical debridement/amputation at the original site of infection within 1 year of initial treatment. Secondary outcomes included the impacts of hemoglobin A1c, peripheral arterial disease, obesity, and infection severity on treatment failure. Results: Among 152 patients meeting criteria, 49 matched pairs were analyzed. Treatment failure rates did not significantly differ between oral and intravenous groups (OR 0.98, 95% CI 0.30–3.19, p > 0.9). A time-to-event analysis similarly found no significant outcome disparities between groups (p = 0.3). Conclusions: The study results support the previously published literature that demonstrates comparable treatment outcomes between routes of antibiotic administration when treating diabetic foot osteomyelitis. Full article

Honey bees (Apis mellifera) are key pollinators in agricultural ecosystems that face increasing pressure from pathogens and environmental change. However, how these environmental factors interact remains incompletely understood. To assess associations between climate, landscape composition, and pathogen occurrence in real agroecosystems, we monitored honey bee colonies across 30 apiaries in southern Italy over two years, in summer and autumn. Molecular screening revealed widespread multi-pathogen exposure, with two viruses, Black Queen Cell Virus (BQCV) and Deformed Wing Virus (DWV), and gut trypanosomatid parasite (Lotmaria passim) being the most frequently detected. In contrast, Nosema ceranae, along with Bee Macula-like Virus (BeeMLV) and Acute Bee Paralysis Virus (ABPV), occurred at lower but still notable frequencies. Infections were generally more frequent in adult foragers than in in-hive bees and larvae, and overall pathogen occurrence tended to be higher in summer than in autumn. Higher humidity was associated with higher overall pathogen occurrence and coinfection levels, whereas higher temperature showed a weaker association with these outcomes. Associations between landscape composition and pathogen occurrence differed across pathogens: a higher proportion of semi-natural habitats was associated with lower viral occurrence, particularly BQCV and DWV; however, N. ceranae was more frequently detected under the same landscape conditions. In contrast, L. passim showed context-dependent responses, with landscape effects emerging only through interactions with humidity and temperature. Pathogen coinfections were more occurrent under warm, humid conditions, although this pattern was partially buffered in landscapes richer in semi-natural habitats. Together, these results indicate that, within the studied apiaries, honey bee pathogen occurrence was associated with climate, season, and land use. These findings suggest that environmental context should be considered when interpreting honey bee health monitoring data in heterogeneous agricultural landscapes, with potential implications for apiary management. Full article

Hepatitis E virus (HEV) is an emerging zoonotic pathogen in Europe, mainly transmitted via consumption of naturally contaminated food or contact with infected animals. People living in the Balkans have diverse dietary habits, with high pork consumption in some countries, making this region a relevant setting for investigating HEV seroprevalence and its possible determinants. The current study aimed to estimate pooled HEV seroprevalence among adults in the general population and blood donors and to assess factors associated with regional variation. Twenty-eight eligible studies were identified from PubMed, Scopus, and Web of Science following the PRISMA guidelines. Pooled prevalence estimates were calculated using a random-effects meta-analysis of proportions implemented via a generalized linear mixed model (GLMM) with logit transformation. Potential factors associated with HEV seroprevalence, including national pork consumption, serological assay type, population group, year of publication, sex, and country, were evaluated. The pooled anti-HEV seroprevalence was estimated to be 5.68% (95% CI: 3.48–9.12%), with substantial heterogeneity. Country-specific estimates ranged from 1.01% in Greece to 26.66% in Bulgaria. Subgroup analyses showed significant variation according to national pork consumption category, serological assay type, year of publication, and country. However, meta-regression indicated that methodological and temporal factors, particularly serological assay type and year of publication, were the main significant moderators, whereas national pork consumption was not independently associated with seropositivity. Therefore, pork consumption should be interpreted as an exploratory ecological indicator rather than as evidence of a direct association. The methodological differences contribute substantially to the variability in HEV seroprevalence across the Balkans, emphasizing the need for standardized diagnostic approaches within a One Health framework. Full article

Pectinolytic bacteria of the Pectobacteriaceae family constitute an important group of plant pathogens. Apart from infected plants, they are regularly found in aquatic environments. Pectinolytic isolates were selected, during 3 years, from water of naturally eutrophic lakes and from the rhizosphere of waterside plants in a site protected from direct agricultural inputs. A total of 89 isolates were assigned to Enterobacterales including the genera Dickeya (62%) and Pectobacterium (13%). In contrast to previous reports showing the prevalence of Pectobacterium species in river water, the Dickeya isolates were largely preponderant in lake water. Six Dickeya and four Pectobacterium species were isolated from water including D. oryzae, D. lacustris, D. parazeae, P. quasiaquaticum and P. aquaticum and, at a low frequency, D. chrysanthemi, D. aquatica, D. zeae, P. brasiliense, and P. versatile. The most common species isolated from plant rhizosphere was D. chrysanthemi. Notably, the rhizosphere of Solanum dulcamara harbored the highest number and diversity of Dickeya and Pectobacterium isolates. Members of different species and/or genera were found in the same water sample or plant rhizosphere, indicating that they can cohabit in close environments. Despite noticeable individual variations, the water strains have a pathogenic potential similar to that of other strains of the same species. Full article

One of the most pressing challenges facing healthcare today is the rise of biofilm infections and antibiotic-resistant bacteria, which demand entirely new therapeutic strategies beyond conventional antibiotic reliance. A biofilm is a structured community of microorganisms encased in a self-produced extracellular polymeric substance (EPS) matrix, which confers resistance to host immune defenses and antimicrobial agents. Accumulating evidence demonstrates that plant-derived secondary metabolites—including flavonoids, phenolic acids, tannins, terpenoids, and alkaloids—exert potent antibacterial and antibiofilm activities through diverse mechanisms of action. These natural compounds inhibit biofilm formation by disrupting bacterial adhesion, suppressing quorum sensing, degrading the EPS matrix, and impairing bacterial motility. Beyond independent bioactivity, phytochemicals demonstrate significant synergistic potential when combined with conventional antibiotics, revitalizing antimicrobial efficacy against drug-resistant pathogens. Nanoformulation and biogenic carrier technologies further enhance the bioavailability and therapeutic potency of these compounds. Despite these advances, critical challenges persist, including poor bioavailability, physicochemical instability, dose-dependent toxicity, and the risk of resistance development. This review presents a critical and integrative analysis of the pharmacological mechanisms of plant secondary metabolites, with particular emphasis on their role in combating biofilm-associated infections and antibiotic resistance, and discusses translational opportunities including structure–activity relationship (SAR)-guided optimization, high-throughput screening platforms, and advanced drug delivery systems. Collectively, plant secondary metabolites represent a scientifically compelling and clinically relevant pipeline for the development of next-generation antimicrobial and antibiofilm therapeutics. Full article

The rapid emergence of antimicrobial resistance has intensified the search for alternative antimicrobial scaffolds that target both planktonic bacteria and biofilm-associated infections. In this study, a series of hydroxylated phosphonium ionic liquids derived from triphenylphosphonium (TPP⁺) and trihexylphosphonium (THP⁺) cations bearing C3, C6, C7, and C10 ω-hydroxyalkyl chains were synthesized and evaluated for their antibacterial and anti-biofilm activities. Antibacterial activity was determined using broth microdilution assays against Staphylococcus aureus and Escherichia coli, while anti-biofilm activity was assessed by disrupting preformed biofilms using a 96-pin microtiter plate system and crystal violet staining. The results showed that antibacterial activity was strongly influenced by the amphiphilic balance of the compounds, particularly the alkyl chain length and the nature of the phosphonium core. Derivatives bearing C6OH–C10OH chains exhibited the highest antibacterial activity, whereas short-chain analogs displayed markedly reduced potency. THP derivatives were notably more active against E. coli bacteria, consistent with their higher hydrophobicity and activity consistent with membrane interaction. In addition, THP derivatives demonstrated greater biofilm disruption, achieving up to ~90% biomass removal in E. coli biofilms, with C6OH–C7OH derivatives showing the most favorable activity profile. Hemolysis assays indicated low erythrocyte toxicity at concentrations close to antibacterial MIC values, indicating a favorable selectivity window. Overall, these findings highlight phosphonium ionic liquids as promising antimicrobial agents with activity consistent with membrane interaction and provide structure–activity insights for the rational design of new antibacterial and anti-biofilm compounds. Full article

Epichloë endophytes enhance plant defense and biotic stress resistance through mutualistic interactions in natural hosts. However, whether these protective effects are retained in annual non-native hosts such as barley (Hordeum vulgare L.) remains unclear. An integrated multi-omics approach was used to characterize defense responses in Epichloë bromicola-infected barley (LD1) and endophyte-free barley (CK) following pathogen challenge. The results show that LD1 had 20.0% lower disease incidence and 24.1% lower disease index than CK. LD1 also exhibited 21.1% lower malondialdehyde (MDA) content and higher antioxidant enzyme activities, indicating more effective control of oxidative damage and improved redox homeostasis. Integrated transcriptomic and metabolomic analyses revealed distinct defense responses between LD1 and CK. LD1 showed stronger activation of glutathione metabolism and antioxidant pathways than CK after 6 h of endophyte inoculation. This was consistent with more efficient control of early reactive oxygen species (ROS) dynamics. By 48 h, LD1 preferentially enriched phenylpropanoid biosynthesis and mitogen-activated protein kinase (MAPK) signaling, accompanied by increased accumulation of defense-related metabolites and enhanced structural and chemical defenses. Collectively, the study demonstrates that Epichloë bromicola enhances disease resistance in barley by reprogramming host defense dynamics from early redox regulation to late structural and chemical reinforcement. Full article

The role of birds of the Strigiformes order in the transmission of globally distributed Sarcocystis parasites remains insufficiently studied. In the present work we aimed to evaluate the diversity of Sarcocystis species in the intestines of 22 naturally infected Tawny Owls (Strix aluco) sampled in Lithuania. The Sarcocystis infection was established using combined light microscopy and DNA sequence analysis. Samples were analyzed using Sarcocystis-genus and species-specific primers in nested PCR followed by Sanger sequencing. Sporocysts of Sarcocystis spp. were detected in 45.5% of samples, while 77.3% of samples were positive by molecular methods. Comparison of 28S rRNA and ITS1 sequences obtained and phylogenetic analyses indicated the presence of eight Sarcocystis taxa: S. halieti, S. kutkienae, S. turdusi, and Sarcocystis sp. ex Corvus corax, associated with birds, and S. funereus, S. glareoli, Sarcocystis sp. LT24Sa1, and Sarcocystis sp. LT24Sa11, associated with small mammals. Our results supplement previous findings that some Sarcocystis species can be transmitted by birds of three orders: Accipitriformes, Falconiformes, and Strigiformes. Overall, the low burden of sporocysts and predominance of single-species infections (63.6%) suggest that Tawny Owls transmit a limited number of Sarcocystis species associated with small mammals and birds. Full article

Background and Purpose: Contrast-enhanced MRI findings of leptomeningeal enhancement (LME) indicate dysfunction of the blood–brain barrier and can be seen in various neoplastic, infectious, and inflammatory conditions. To the best of our knowledge, systematic evaluation of different patterns of LME remains limited. This case series aims to describe and compare MRI patterns of leptomeningeal enhancement across diverse etiologies. Materials and Methods: We retrospectively evaluated six patients with known or suspected leptomeningeal disease on contrast-enhanced MRI studies of the brain and/or spine with regard to pattern, distribution, localization, and thickness of LME. Results: The patterns of neoplastic causes (glioblastoma, lymphoma, and adenocarcinoma) were characterized by diffuse, thick, and nodular LME, as well as frequently affected cranial nerve and nerve-root involvement. The infections caused various patterns: in cases of tuberculous meningitis, LME was focal and basal in nature, accompanied by parenchymal lesions; whereas in cases of HIV-related meningitis, LME was diffuse and exhibited a pseudocisternogram pattern. The inflammation (suspected neurosarcoidosis) revealed smooth-to-nodular LME with spinal and suprasellar involvement. Conclusions: Although LME patterns are not specific, systematic evaluation of enhancement characteristics may provide useful diagnostic clues and assist in narrowing the differential diagnosis. Full article

Marine algal viruses exhibit a high level of diversity, and closely related viruses targeting the same algal host species can stably coexist. Here we report an example of a single virus–host system concealing hidden complexity. We discovered two double stranded (ds) DNA viruses infecting the Arctic picophytoplankter Micromonas polaris coexisting in culture for over a decade. Genomic sequencing of the lysate originally characterized as MpoV-44T revealed that it comprises two distinct prasinoviruses with ~203–204 kb genomes (MpoV-44T.A and MpoV-44T.B), of which conserved regions only accounted for 36% (the nucleotide level). The viruses were subsequently separated and compared at both genomic and phenotypic levels. In dual infection studies using a single host strain under nutrient-replete conditions, MpoV-44T.A outcompeted MpoV-44T.B. Yet MpoV-44T.B-like viruses were more abundant than MpoV-44T.A-like ones in natural Arctic metagenomes. This apparent paradox may be explained by differences in host strain specificity and/or possible resilience to nutrient stress by MpoV-44T.B, which we hypothesize based on genomic data. This work unveils hidden virus diversity, illustrating that the dynamics of viral coexistence are not always easily predictable, and underscores the importance of studying the underlying mechanisms at play. Full article

Nipah virus (NiV) is a highly pathogenic zoonotic pathogen. Since its discovery in 1998, recurrent epidemics have occurred in South and Southeast Asia, with a case fatality rate ranging from 40% to 100%. The outbreak in West Bengal, India in early 2026 has once again highlighted its severe threat to public health. To date, no licensed human vaccines or specific therapeutics against NiV are available worldwide. This review systematically summarizes the breakthroughs in antigen design for NiV vaccines, with a focus on conformational stabilization of prefusion F (pre-F) protein, chimeric G/F antigens, and multivalent nanoparticle strategies. In addition, we comparatively analyze the clinical progress of mainstream vaccine platforms, including viral vectors, mRNA and subunit vaccines. Given the sporadic nature and high mortality of NiV infection, the conventional licensing pathway relying on large-scale phase III clinical trials faces substantial practical obstacles. Accordingly, this article discusses adaptive adjustments in regulatory science. We propose several strategies to accelerate the clinical translation and emergency stockpiling of NiV vaccine candidates, including establishing unified correlates of protection thresholds, coordinating multinational regulatory resources, and optimizing the implementation of Animal Rule. Full article