Search Results (4,759)

Brown bear populations in Greece face multiple threats, and parasitic infections may pose an additional risk to these vulnerable animals. This study represents the first comprehensive assessment of endoparasite occurrence, prevalence, and seasonality in brown bears in Greece, in relation to geographical location and the animal’s different physiological phases. A total of 918 faecal samples were collected over a three-year period from regions with brown bear presence in Greece. For each sample, the date of collection and the coordinates of the site were recorded. Samples were examined using sedimentation, flotation, and McMaster techniques, while the Baermann method was additionally applied to a subset of 195 samples. Spatial and temporal patterns in parasite occurrence and diversity were analysed using generalised additive models (GAMs). Ten parasitic taxa were identified, with Baylisascaris transfuga being the most prevalent (39.8%), followed by Crenosoma spp. (26%), Uncinaria spp. (18.09%), and Dicrocoelium dendriticum (14.38%). Less prevalent taxa included Eucoleus aerophilus, Sarcocystis spp., Toxascaris leonina, Eimeria spp., Linguatula serrata, and Taeniidae. Μixed infections, involving two or more parasites, were detected in 22% of the samples. The prevalence of B. transfuga was higher in late autumn, with high-risk infection areas identified in both late summer and autumn. In contrast, Uncinaria spp. and D. dendriticum showed no seasonal variation, while D. dendriticum exhibited spatial clustering patterns similar to B. transfuga but without clear seasonal trends. These findings highlight the widespread occurrence and complexity of parasitic infections in Greek brown bears. Continued long-term monitoring is essential to improve understanding of transmission dynamics and the ecological processes shaping parasite distribution in this animal species. Full article

Objective: Perform endoscopic surgery for radiculopathy caused by compression fractures and evaluate the results. Methods: A total of 20 patients who underwent biportal endoscopic foraminotomy and unilateral screw fixation using a dynamic rod for radiculopathy secondary to osteoporotic compression fractures were included in this study. All surgeries were performed between July 2021 and January 2025. Patient demographic data, operated level, length of hospital stay, intraoperative blood loss, and operative time were reviewed. Radiological follow-up included assessment of segmental kyphosis, scoliosis, subsidence, and adjacent-level fractures. Complications and pain patterns—separately evaluated for back pain and radiculopathy—were assessed using the visual analog scale (VAS) preoperatively and during follow-up. Only single-level cases were included. Patients with infections, significant stenosis, instability, tumors, prior revision surgery, multilevel pathology, or ambiguous symptoms were excluded. Results: The mean age of the patients was 78.8 years (range, 69–89 years), reflecting an elderly cohort. The mean follow-up period was 13.0 ± 11.9 months (range, 1–41 months). The mean operative time was 164.8 ± 25.7 min, and the mean hospital stay was 10.2 ± 4.6 days (range, 4–25 days). The mean intraoperative blood loss was 126.5 ± 77.6 mL (range, 50–400 mL). One female patient developed postoperative pneumonia, which resolved after appropriate treatment; no other medical complications were observed. Radiculopathy improved significantly immediately after surgery and continued to improve during follow-up. Back pain also improved, but tended to persist to a mild degree. Radiologic evaluation revealed no significant changes in segmental lordosis, and there were no cases of subsidence, scoliosis, or symptomatic screw loosening during the available follow-up period. Conclusions: Biportal endoscopic foraminotomy with unilateral screw fixation may be an effective solution for radiculopathy caused by compression fractures. Full article

While minimalist kinetic models effectively capture the acute inverse coupling between Hepatitis B (HBV) and Hepatitis Delta (HDV), they often fail to account for the asymptotic stability and long-term viral plateaus observed during clinical therapy. In this work, we present an expanded compartmental framework integrating the non-linear dynamics of susceptible (S) and infected (I) hepatocyte populations, explicitly incorporating the satellite nature of HDV. Using the next-generation matrix method and Lyapunov stability theory, we analytically derive R₀ and prove the global attractivity of the endemic equilibrium. We demonstrate that “Target Cell Limitation” serves as the fundamental homeostatic governor. A transcritical bifurcation at threshold drug efficacy ε ≈ 0.9 marks the mathematical boundary between chronic persistence and viral extinction. Full article

Rift Valley fever virus (RVFV) and Crimean–Congo hemorrhagic fever virus (CCHFV) are endemic zoonotic pathogens in Senegal, transmitted by mosquitoes and ticks, respectively. Understanding the seasonal and spatial dynamics of their vectors is essential to improve targeted surveillance. This study investigated the abundance, diversity, and viral infection status of vector populations in a transboundary region (Matam) and a non-transboundary region (Thiès) over two seasons from September 2022 to March 2024. We collected mosquitoes using CO2-baited CDC light traps and sampled ticks directly from domestic small ruminants. A total of 6558 mosquitoes across 23 species and 1904 ticks representing seven species were morphologically identified. Mosquito abundance peaked significantly during the rainy season. Conversely, tick diversity increased during the dry season, with Hyalomma rufipes emerging as the predominant species. Crucially, RVFV was detected exclusively in Aedes vexans mosquito pools from the transboundary Matam region, emphasizing the epidemiological risk associated with cross-border livestock mobility. Viral RNA of CCHFV was detected in multiple tick species across both regions and seasons, confirming a sustained, multi-vector enzootic cycle. These findings demonstrate persistent RVFV and CCHFV circulation in Senegal and highlight the critical need for integrated, season-specific vector surveillance frameworks. Full article

Vibrio tubiashii infection has led to several Babylonia areolata pandemics on the southeast coast of China, yet the immune response of the ivory shell against V. tubiashii and the specific pathogen–host interaction remain unclear. This dynamic study aimed to characterize the response of B. areolata to V. tubiashii infection with the use of pathology, transcriptomics, an enzymatic assay, and inflammatory cytokines. Hepatopancreatic cells showed marked vacuolar degeneration with intact cell membrane and extensive cytoplasmic vacuolization after infection. The dynamic transcriptome of the hepatopancreatic tissue was analyzed by RNA-seq after V. tubiashii infection, and a total of 2733 (3 h), 5610 (24 h), 3323 (48 h), and 418 (72 h) differentially expressed genes (DEGs) were identified during infection. The GO and KEGG analyses showed that the DEGs were enriched in metabolic regulation, lysosome, and multiple immune-related pathways such as the MAPK signaling pathway. The immune response of B. areolata was distinct, where the early stage of immune response (3 h) showed binding, focal adhesion, and apoptosis, as well as an activated antioxidant system. Here, expression of TNF-α, IL-1, and IL-8 was significantly increased in the hepatopancreas, whereas expression of IL-6 and IL-17 increased afterward. During the middle stage (24 h and 48 h), a large number of DEGs were suppressed, especially those associated with metabolism and lysosomes, although their expression returned to normal during prolonged infection (72 h). The PPI network showed that ppp2, atp6, and sos1 were the top immune-related DEGs during infection. Key infection-related and time-course-related genes were analyzed by WGCNA. This study illustrates that oxidative stress, inflammation, and apoptosis are strategies of the hepatopancreatic immune response in B. areolata against V. tubiashii infection and enlightens conservation and production by furthering our understanding of gastropod immunity. Full article

Pollen constitutes the primary source of proteins, amino acids, lipids, sterols, vitamins, and minerals for honey bees. However, not all pollen types provide the same resources or have the same biological value. Its chemical composition changes according to botanical origin, geographic location, and environmental conditions. This variability can influence metabolism, the immune system, oxidative balance, and the ability to resist or tolerate infections. This article examines the available evidence on the relationship between pollen chemical quality and the dynamics of Deformed Wing Virus (DWV) infection in Apis mellifera. The analysis is approached from molecular, physiological, ecological, and seasonal perspectives. Current findings suggest that more diverse and higher-quality pollen diets are generally associated with greater colony survival and improved health status, although their effects on viral load are more heterogeneous and context-dependent. In some studies, pollen intake is linked to a reduction in DWV, whereas in others viral loads remain stable or even increase despite improvements in survival, physiological condition, or colony performance. These differences suggest that pollen may act not only by enhancing resistance to the virus but also by increasing tolerance to infection-associated damage. The potential role of pollen bioactive compounds, particularly flavonoids and phenolic acids, is also discussed. Nevertheless, evidence of direct antiviral action of these compounds in bees remains limited, as many proposed mechanisms derive from other organisms. This synthesis provides an integrative perspective on pollen nutrition and its relevance for colony resilience against viral infections. Full article

Circadian rhythms impose temporal organization on immune function, shaping host responses to infection, injury, and chronic disease. While transcriptional control by core clock components such as CLOCK and BMAL1 has been extensively characterized, this paradigm alone cannot explain the rapid and dynamic nature of immune signaling. Emerging evidence identifies post-translational modifications (PTMs)—including phosphorylation, ubiquitination, and acetylation—as critical regulators that confer speed, reversibility, and specificity to inflammatory pathways. Here, we propose the concept of a “Chrono-PTM axis,” in which circadian timing and PTM-dependent signaling are functionally integrated to govern immune activation thresholds. We discuss how PTMs not only regulate core clock machinery but also temporally gate key innate immune pathways, including NF-κB signaling and inflammasome activation, thereby controlling cytokine production at multiple levels. Furthermore, we highlight the role of immunometabolism in supplying essential cofactors that couple cellular energetic states to PTM dynamics, linking metabolic oscillations to inflammatory outputs. Disruption of this axis contributes to the pathogenesis of autoimmune diseases, cancer, and tissue-specific inflammatory disorders. Finally, we outline emerging therapeutic opportunities targeting the Chrono-PTM axis, including chronotherapy and PTM-directed interventions, and identify critical gaps in temporal proteomics and translational studies. Elucidating the integration of circadian and post-translational regulation will provide a unifying framework for understanding immune homeostasis and may enable time-informed precision immunotherapy. Full article

Background: SARS-CoV-2 infection has been associated with metabolic disturbances and endocrine alterations, including effects on pancreatic β-cell function and thyroid hormone regulation. However, the relationship between thyroid function and β-cell compensatory capacity in the post-COVID state remains unclear. Methods: In this cross-sectional study, we evaluated β-cell compensation (HOMA-B/HOMA-IR) and thyroid parameters in three groups: patients with active COVID-19, individuals with post-COVID metabolic disturbances, and a COVID-negative metabolic syndrome reference group. Thyroid status was assessed using both comprehensive clinical classification and biochemical criteria. Associations between thyroid hormones and β-cell function were analyzed using Spearman correlation. Results: β-cell compensatory capacity differed significantly across groups, with the lowest values observed during active COVID-19 and intermediate impairment in the post-COVID cohort compared with the metabolic syndrome group. FT3 concentrations and the FT3/FT4 ratio were significantly reduced during active infection and were positively associated with β-cell compensation in the post-COVID group (ρ = 0.421, p = 0.018 and ρ = 0.382, p = 0.031, respectively). Although thyroid dysfunction appeared more prevalent in the post-COVID cohort when defined by overall clinical classification, no significant differences were observed when thyroid status was evaluated based solely on biochemical criteria, excluding clinical history and euthyroid sick syndrome. Conclusions: Post-COVID metabolic disturbances are characterized by impaired β-cell compensatory capacity and alterations in peripheral thyroid hormone dynamics. The apparent increase in thyroid dysfunction is largely driven by pre-existing thyroid disease and non-thyroidal illness effects rather than intrinsic thyroid pathology. These findings are consistent with the hypothesis of a potential post-COVID immunometabolic phenotype involving both pancreatic and thyroid-related mechanisms. Full article

We propose a fractional-order cancer virotherapy model based on Caputo derivatives to investigate the temporal interactions among tumor cells, viruses, and immune response components. The existence and uniqueness of the solutions for the proposed model are rigorously studied. The proposed model is capable of tracking the temporal dynamics of uninfected and infected cancer cells, free oncolytic virus, and several components of the immune response. To determine the analytical solutions of the resulting nonlinear fractional-order system, we utilize the Temimi–Ansari method (TAM). The convergence and accuracy of the method are confirmed via error analysis and numerical simulation carried out in MATHEMATICA. It is observed that the fractional order plays a prominent role in controlling the temporal dynamics of the cancer–virus–immune system, leading to a reduction in the number of infected cancer cells due to virotherapy. On the other hand, the immune response is vital for controlling cancer growth. Full article

Background: Viral attachment mediated by host cell surface receptors is the first step in viral infection. As a key cell surface receptor, heparan sulfate (HS) mediates the attachment and entry of numerous non-enveloped viruses in livestock, thereby serving as a crucial molecular target for studying virus–host interactions. Methods: Based on the structural scaffold of a nanobody (Nb; PDB: 7TJC), we rationally designed and constructed a mutant Nb targeting HS, designated HS-Mut-Nb1, using molecular docking, site-directed mutagenesis, molecular dynamics (MD) simulations, and experimental characterization. Results: Molecular docking indicated that the active site of wild-type Nb for HS binding was located within the cavity jointly formed by the complementarity-determining region 3 (CDR3) and the framework regions (FRs) of the wild-type Nb. A comprehensive analysis integrating virtual alanine scanning, site-directed mutagenesis, and MD simulations revealed that the combination of three point mutations (Phe47Arg, Asp99Tyr, and Tyr108Pro) significantly enhanced the binding affinity of Mut-Nb1 for HS, with a calculated binding free energy (ΔG) of −83.26 ± 3.06 kcal/mol. Enzyme-linked immunosorbent assay (ELISA) results further confirmed that Mut-Nb1 exhibited high affinity for HS (K_D = 65.87 nM) and specificity (positive/negative ratio, P/N = 3.84; cross-reactivity, CR < 6.60%). Conclusions: This study not only provides novel candidate molecules for elucidating the mechanism of HS–virus interactions and developing related inhibitors but also offers a reference for the rapid construction of mutant Nbs. Full article

Human papillomavirus (HPV) infection is a major driver of anogenital disease and virus-related carcinogenesis. Although most infections resolve spontaneously, persistent infection with high-risk genotypes may progress to high-grade squamous intraepithelial lesions (HSILs) and cancer, particularly in the setting of impaired immune surveillance. Unlike previous HPV-related reviews focused primarily on cervical disease, vaccination, or isolated immunosuppressed populations, this narrative review comparatively examines the clinical expression, colposcopic findings, screening strategies, and therapeutic implications of HPV-related disease across the immunological spectrum. This narrative review provides an integrative synthesis of HPV-related disease in the female lower genital tract across the immunological spectrum. A structured, non-systematic search of PubMed/MEDLINE, Scopus, and Web of Science was conducted using terms related to “human papillomavirus”, “HPV”, “cervical intraepithelial neoplasia”, “colposcopy”, “immunosuppression”, “HIV”, and “vaccination”. Immunosuppressed populations, including individuals living with HIV, transplant recipients, and patients receiving immunosuppressive therapy, exhibit higher rates of persistent infection, multifocal disease, recurrence, and progression to HSIL and invasive malignancy. These patients also present greater diagnostic complexity, broader anatomical involvement, and reduced response to conventional treatment. Rather than representing a uniform condition, HPV-related disease reflects a biologically dynamic spectrum shaped by host immune competence. This review highlights the distinct clinical, colposcopic, and therapeutic challenges observed in immunosuppressed populations and reinforces the need for individualized, risk-adapted strategies integrating contemporary advances in screening, vaccination, and HPV-related disease management. Full article

Schistosomiasis remains a major public health concern in Nigeria. We molecularly characterized Schistosoma eggs obtained from human urine to identify species and assess the presence of hybrid schistosomes in Abuja, Nigeria. Urine samples were collected from 1887 participants aged five years and above. Samples were examined for Schistosoma eggs using light microscopy. A total of 507 (26.9%) were positive for any form of Schistosoma while 91 (4.8%) had atypical Schistosoma eggs. DNA extracted from pooled ova was analyzed using metagenomic sequencing, read mapping, phylogenetic analysis, and BLASTn confirmation. Molecular analyses identified genetic signatures associated with both S. haematobium and S. bovis within pooled human urine samples, indicating the co-circulation of multiple schistosome species in the study area. Phylogenetic analyses based on trans-ITS and mitochondrial COX1 markers supported the presence of distinct nuclear and mitochondrial schistosome lineages. However, because sequencing was performed on pooled egg samples, the findings cannot distinguish between true recombinants and mixed infections involving co-circulating parental species. These findings highlight the potential complexity of schistosome transmission dynamics in endemic communities and underscore the need for enhanced molecular surveillance, especially single-parasite genomic approaches, and integrated One Health investigations to better understand schistosome transmission and its implications for control and elimination efforts in Nigeria. Full article

Grapevine downy mildew, caused by the oomycete pathogen Plasmopara viticola (P. viticola), is one of the most devastating diseases threatening the global grape industry. The pathogen invades host plants through stomata, triggering a series of highly coordinated physiological disorders and biochemical defense events. This review systematically summarizes the dynamic changes in morphological structures (stomatal characteristics), physiological functions (photosynthesis, membrane system integrity, and carbon metabolism), and multi-level biochemical defense systems (reactive oxygen species (ROS) scavenging enzyme system, phenylpropanoid metabolic pathway, pathogenesis-related proteins, and phenolic compounds) in grapevines following infection. It focuses on analyzing the differences in the timing, intensity, and metabolic reprogramming of defense responses between resistant and susceptible cultivars, pointing out that the essence of disease resistance lies in early pathogen recognition and rapid defense induction. The conflicting conclusions regarding indicators such as soluble sugars, peroxidase (POD), and superoxide dismutase (SOD) are discussed from the perspectives of experimental systems, cultivar genetic backgrounds, and pathogen physiological race differences. Furthermore, the known physiological and biochemical alterations are linked to upstream signaling pathways, including salicylic acid and jasmonic acid (SA/JA), calcium signaling, and mitogen-activated protein kinase (MAPK) cascades. Recent advances in revealing resistance mechanisms in the omics era are also introduced. Finally, future research directions are proposed, including constructing multi-indicator dynamic evaluation models, verifying key gene functions using gene editing, exploring the potential of epigenetic regulation, and developing integrated control strategies combined with microbiome research. This review aims to provide theoretical support for grapevine downy mildew resistance breeding and sustainable disease management. Full article

This study aimed to determine whether intranasal hinokitiol modulates short-term salivary secretory IgA (SIgA) secretion dynamics and IgA antibody-forming cell (AFC) activity in the submandibular glands of aged mice, a model of age-associated mucosal immune decline. Aged BALB/c mice received intranasal hinokitiol (50 μg) once weekly for 4 weeks. Saliva was collected on days 0, 7, 14, and 21 at baseline, 0.5 h, 1.5 h, 3 h, and 6 h after each administration. SIgA levels were measured using an enzyme-linked immunosorbent assay. On day 21, IgA AFCs were enumerated using an enzyme-linked immunosorbent spot assay, and their viability and proliferative activity were assessed using the MTT assay. Salivary SIgA rose transiently after each dose, peaking at 1.5 h and returning to baseline by 6 h. By day 21, baseline SIgA secretion was significantly higher than at day 0, indicating a cumulative effect. IgA AFCs were unchanged in number, but viability and proliferation increased at 0.5 and 1.5 h, coinciding with SIgA peaks. Flow cytometry revealed significant expansion of B220⁺CD38⁺ memory B-cells; B220⁺CD138⁺ plasma cells were unaffected. Intranasal hinokitiol transiently enhances salivary SIgA secretion in aged mice, likely through short-term modulation of salivary gland immune activity. This non-invasive approach may aid mucosal defense in aging populations. These findings suggest that intranasal HNK may represent a novel non-invasive approach for enhancing mucosal immune function during aging and may provide a basis for future preventive strategies against oral and respiratory infections. Full article

Listeria monocytogenes is a ubiquitous Gram-positive bacterium responsible for listeriosis, a foodborne zoonotic disease affecting humans and animals. Although infection in immunocompetent individuals is often asymptomatic or limited to mild self-limiting gastroenteritis, Listeria monocytogenes may cause severe invasive disease in vulnerable groups, including pregnant women, neonates, elderly individuals, and immunocompromised patients. Although the incidence of listeriosis is relatively low compared with many other foodborne pathogens, the high hospitalization and mortality rates associated with clinical cases make this bacterium a major concern for food safety and public health. The evolutionary success of L. monocytogenes reflects the interaction between a conserved core genome and a dynamic accessory genome shaped by horizontal gene transfer (HGT), ecological selection, and expansion of specific clones. Transient intestinal carriage in humans and animals, potentially influenced by gut microbiome composition, creates ecological interfaces where plasmids, transposons, prophages, and integrative conjugative elements contribute to the exchange of antimicrobial resistance determinants, virulence factors, and stress tolerance systems. Virulence diversification is further influenced by the differential distribution of pathogenicity islands such as LIPI-1, LIPI-3, and LIPI-4 across specific clonal lineages. These evolutionary processes occur across interconnected farm, food-production, environmental, and clinical ecosystems consistent with the One Health framework. Advances in whole-genome sequencing have clarified lineage-specific gene flow, expansion of specific clones, and the dynamics of the resistome and mobilome in L. monocytogenes populations. This narrative review aims to synthesize current knowledge on the mobile genetic elements and ecological interfaces that shape horizontal gene transfer in L. monocytogenes. Its novelty lies in integrating antimicrobial resistance, virulence-associated genomic islands, stress adaptation, and gut microbiome-mediated selection within a One Health and metapopulation framework. The main message of this review is that HGT should be interpreted as a context-dependent contributor to L. monocytogenes adaptation, acting together with clonal background, ecological selection, and mobile genetic elements. Full article