Search Results (3,532)

Background: The intracellular pathogen Brucella requires biotin for survival, yet the role of its de novo synthesis intermediate enzyme, BioA, in virulence remains undefined. This study investigates the contribution of BioA to the pathogenicity of Brucella abortus. Methods: We constructed a ΔBioA mutant in Brucella abortus 104M via homologous recombination and characterized its phenotype using growth assays, electron microscopy, macrophage infection models, and murine splenic colonization. Virulence gene expression was quantified by RT-qPCR. Results: The ΔBioA mutant exhibited severe growth auxotrophy in a biotin-deficient medium and displayed damaged outer membrane integrity. Furthermore, intracellular survival in macrophages was reduced by approximately 95% compared to the wild-type strain at 48 h post-infection. Notably, mice infected with the mutant showed a significant decrease in both splenic bacterial loads and spleen weight at 3 weeks, concomitant with a marked downregulation of VirB type IV secretion system (T4SS) genes. Conclusions: This study is the first to identify BioA as a critical nexus linking biotin metabolism to Brucella virulence. We demonstrate that BioA deficiency attenuates pathogenicity by impairing both structural integrity and the transcription of key virulence-related genes (VirB operon), thereby nominating BioA as a novel and promising target for anti-brucellosis interventions. Full article

Kratom (Mitragyna speciosa) is a botanical candidate for pain management with potentially reduced opioid-related risks, partly through modulation of neuroimmune pathways involving Toll-Like Receptor 4 (TLR4). This study aimed to characterize the phytochemical profile of kratom ethanol extract and evaluate its effects on TLR4 signalling, neuroinflammatory cytokines, analgesic activity, withdrawal behaviours, and organ safety in morphine-dependent mice. Metabolite profiling was conducted using UHPLC–Q-Exactive Orbitrap HRMS, followed by molecular docking of major constituents to the TLR4 complex. In vivo assessments included flow cytometry and gene expression analyses of TLR4-mediated cytokines (NF-κB, IL-1β, IL-6), behavioural assays for antinociception, endurance, and withdrawal symptoms, and histopathological and biochemical evaluation of liver, kidney, and spleen tissues. More than 100 metabolites were identified, including mitragynine and flavonoids such as rutin and isoquercetin, which showed interactions with key TLR4 residues. Selected fractions suppressed pro-inflammatory cytokine expression, increased tail-pinch latency comparable to morphine, reduced withdrawal manifestations, and demonstrated nephroprotective and immunomodulatory effects, although mild reversible hepatic alterations were observed in specific fractions. Overall, kratom ethanol extract exhibited fraction-dependent analgesic and anti-neuroinflammatory activities associated with TLR4 modulation, supporting its potential as a botanical analgesic candidate while emphasizing the importance of safety optimization and standardized fraction development. Full article

Background: Pancreatic neuroendocrine neoplasms (PanNENs) represent a heterogeneous tumor entity with a steadily rising incidence, mainly due to advances in imaging and growing diagnostic awareness. In pancreatic ductal adenocarcinoma (PDAC), the mesopancreas (MP) has been identified as a frequent site of microscopic tumor spread and a key determinant of circumferential resection margin (CRM) status, leading to the concept of standardized mesopancreatic excision (MPE). While its oncological relevance in PDAC is increasingly recognized, the role of the mesopancreas in PanNENs remains unclear. This study aimed to systematically evaluate mesopancreatic infiltration in PanNENs and to identify associated clinicopathological predictors. Methods: Consecutive patients undergoing oncological pancreatoduodenectomy, spleen-preserving distal pancreatectomy, or distal splenopancreatectomy for PanNENs and PanNECs were included. The mesopancreas was histopathologically examined for tumor infiltration within CRM assessment. Results: MP infiltration was detected in 60% of patients. It was associated with higher Ki-67 index, larger tumor size, lymph node involvement, venous invasion, and positive CRM status. A Ki-67 index ≥ 5% and tumor size ≥ 21.5 mm were identified as predictors of MP infiltration. Higher T stage predicted reduced overall survival (OS), whereas MP infiltration, lymphatic (L1) and venous (V1) invasion, and Ki-67 ≥ 5% were associated with impaired disease-free survival (DFS). Conclusion: Mesopancreatic infiltration is frequently present in PanNENs and correlates with aggressive tumor characteristics. Given its association with CRM positivity and reduced DFS, consideration of the mesopancreas in staging and surgical strategies appears oncologically justified. Larger studies are required to validate these findings. Full article

The gut microbiota serves as a critical interface for host immunity, making it a promising target for probiotic intervention. In this study, we investigated the immunomodulatory potential of the strain Bifidobacterium breve (B. breve) MN15965 and the underlying role of gut bacterial communities in this process. We first assessed its in vitro immunomodulatory activity by measuring nitric oxide and cytokine secretion in THP-1 macrophages. Subsequently, an immunosuppressed mouse model was established by treating BALB/c mice with cyclophosphamide (CTX), a chemotherapeutic agent known to cause immune dysfunction and mucosal damage. In this model, we performed a series of analyses, including H&E staining, measurement of hematological parameters and serum cytokines/immunoglobulins, quantification of fecal short-chain fatty acids (SCFAs) by gas chromatography, and profiling of gut microbiota composition via 16S rRNA gene amplicon sequencing. The results showed that MN15965 supernatant enhanced TNF-α, IL-1β, and GM-CSF secretion in THP-1 cells, promoting M1 macrophage activation in vitro. In the in vivo model, MN15965 administration restored spleen and thymus tissue integrity and improved physiological indices, hematological parameters, and immunoglobulin levels. Furthermore, MN15965 increased fecal SCFAs, particularly butyric and valeric acid, increased gut bacterial diversity, and enriched potentially beneficial SCFA-producing taxa, including Lachnospiraceae and Eubacterium. These findings demonstrate that B. breve MN15965 alleviated CTX-induced immunosuppression by activating immune responses, regulating gut bacterial communities, and boosting SCFA production. Full article

Chikungunya virus (CHIKV) infection presents a wide spectrum of clinical outcomes, ranging from mild self-limiting disease to severe and fatal manifestations, which are influenced by both host and viral factors. Animal models are essential for elucidating CHIKV pathogenesis and for preclinical evaluation of antiviral strategies; however, a well-characterized model evaluating the effect of different viral doses in AG129 mice remains limited. In this study, we investigated the clinical, virological, and pathological outcomes of CHIKV infection in male AG129 mice inoculated intraperitoneally with different viral doses (10, 100, and 1000 PFU/mL) of a Brazilian strain belonging to the East/Central/South African (ECSA) lineage. Lower-dose inoculation (10 PFU/mL) resulted in a milder disease course, characterized by transient viremia, limited tissue viral dissemination, minimal histopathological alterations, partial survival, and viral clearance. In contrast, higher doses (≥100 PFU/mL) led to rapid systemic viral dissemination, severe histopathological damage in the spleen, liver, and kidneys, and uniform lethality. Viral RNA was detected in serum and multiple organs in a time-dependent manner, with limited differences among inoculum doses in most tissues. Notably, dose-related differences were observed in specific compartments and time points, particularly in hind-limb muscles at early time points and in serum at later stages. Full article

Background: Midkine (MDK), a secreted heparin-binding growth factor, is involved in tumor progression and metastasis. While serum MDK is widely recognized as a potential prognostic biomarker for colorectal cancer (CRC), its specific functional role and underlying mechanisms in CRC development are not fully understood. Methods: The four publicly available CRC microarray datasets—GSE41258, GSE44076, GSE81558, and GSE117606—along with TCGA-COAD and TCGA-READ datasets and their associated clinical data were obtained. MDK expression was measured at both the mRNA and protein levels using quantitative real-time PCR (qRT-PCR) and Western blotting. To investigate its oncogenic functions, a comprehensive set of assays was performed: transwell and wound healing assays for invasion and migration; CCK-8 and colony formation assays for proliferation; and tail vein/spleen injection models combined with xenograft models to study metastasis and tumor growth in vivo. To uncover underlying mechanisms, Western blotting was used to examine the involvement of epithelial–mesenchymal transition (EMT) and the PI3K/AKT signaling pathway. Results: MDK is significantly overexpressed in CRC tissues and cells compared to normal tissues and cells. Notably, patients with high MDK levels show poorer overall survival (OS). Overexpression of MDK increases CRC invasion, migration, proliferation, and metastasis both in vivo and in vitro, while its knockdown reverses these effects. Mechanistically, MDK activates the PI3K/AKT pathway, leading to increased AP2A1 expression and promotion of EMT in CRC. Conclusions: MDK promotes invasion, migration, proliferation, metastasis, and EMT in CRC cells through the PI3K/AKT pathway by inducing AP2A1 expression, which could serve as a diagnostic marker. The PI3K inhibitor LY294002 significantly reduces AP2A1 levels and inhibits MDK-induced malignant behaviors. Targeting MDK-related signaling pathways may offer new strategies for CRC treatment. Full article

Background: Splenic marginal zone lymphoma (SMZL) is a rare indolent lymphoma with extremely limited population-level evidence on social and treatment correlates of survival. Methods: We conducted a retrospective cohort study using SEER (2000 to 2022) to evaluate OS in primary SMZL (ICD O 3 9689; spleen C42.2). We summarized baseline features and treatments and used Kaplan–Meier and Cox regression. Results: The cohort included 3548 patients (mean age: 68.2 years; 53.6% female). Most were White (89.8%) and non-Hispanic (92.1%). The Ann Arbor stage was missing in 39.4%. Treatment included systemic antineoplastic therapy in 26.4%, beam radiation in 0.7%, and primary site surgery in 21.4%. At last follow-up, 56.8% were alive; non-Hodgkin lymphoma accounted for 15.8% deaths in the cohort, with substantial competing causes including heart disease (6.1%). In multivariable Cox analysis, OS was independently associated with age (HR 1.082 per year, 95% CI 1.072–1.091), male sex (HR 1.34, 95% CI 1.14–1.57), Hispanic ethnicity (HR 1.42, 95% CI 1.08–1.88), systemic antineoplastic therapy (HR 1.42, 95% CI 1.18–1.70), divorced/separated marital status vs. married (HR 1.35, 95% CI 1.03–1.77), and stage IV disease (HR 1.70, 95% CI 1.16–2.50). Race and year of diagnosis were not independently associated with OS in the adjusted model. Conclusions: In our large population-based analysis, OS in SMZL tracks with demographic and social variables and competing risks. Stage missingness and treatment selection limit causal inference for management effects. Full article

Differences in the gut microbiota are directly reflected in lung–gut axis crosstalk, which may increase susceptibility to pulmonary infections, such as those caused by the bacterium Pseudomonas aeruginosa. Deficiency of the cytokine IL-10 leads to gut inflammation, and this pro-inflammatory environment is partly due to changes in the gut microbiota. To better understand the effects of IL-10 deficiency on the gut microbiota, the intestinal microbial composition of IL-10 KO mice was assessed, and an increase in the phyla Bacteroidetes and Proteobacteria and a decrease in the phylum Firmicutes were observed in the faeces compared with the wild-type group (WT). Additionally, IL-10 KO mice had a higher pro-inflammatory immunostimulatory caecal content. Furthermore, it was found that heterologous faecal microbiota transplantation (FMT) between groups reversed this gut imbalance. IL-10 KO mice showed greater susceptibility to acute pulmonary infection by P. aeruginosa, with a higher recovery of viable bacteria in the lung and spleen, greater tissue damage and increased expression of genes encoding pro-inflammatory cytokines in the lungs. This greater susceptibility was reversed after FMT. Taken together, these results demonstrate the role of endogenous IL-10 in the gut microbiota constitution and its importance in the pulmonary immune response against P. aeruginosa infection. Full article

Atopic dermatitis (AD) is a chronic inflammatory dermatosis driven by skin barrier dysfunction, immune dysregulation, and gut–skin axis imbalance. While probiotics show promise, the therapeutic potential and mechanisms of topical postbiotics in modulating the gut–skin axis remain understudied. Here, we investigated the efficacy of Schleiferilactobacillus harbinensis JNDM-derived cell-free supernatant (CFS) and lysate (ShL) in a DNFB-induced AD mouse model. Topical application of both CFS and ShL significantly attenuated AD-like symptoms, reduced epidermal thickening, and restored the expression of the barrier protein filaggrin. Immunologically, treatment suppressed the Th2-dominant inflammatory cascade (IL-4, IL-5, IL-13, IL-33, TSLP) and reduced serum IgE and IFN-γ levels. Notably, ShL exhibited superior systemic efficacy, significantly inhibiting mast cell infiltration and reducing the spleen index. 16S rRNA sequencing revealed that topical intervention remotely remodeled the gut microbiota, specifically reversing the depletion of the beneficial genus Alistipes and suppressing the compensatory increase in Odoribacter. This microbial restructuring was accompanied by distinct metabolic changes: ShL treatment resulted in an approximately 4-fold elevation in fecal butyrate concentrations compared with the model group. Correlation analysis further validated a strong positive axis linking Alistipes abundance and butyrate levels to skin barrier integrity. Collectively, our findings demonstrate that S. harbinensis postbiotics—particularly the lysate—ameliorate AD through a dual mechanism of local barrier repair and systemic metabolic modulation via the gut–skin axis, presenting a promising non-steroidal therapeutic strategy. Full article

Attention-Deficit/Hyperactivity Disorder (ADHD), affecting 5–10% of children globally, faces treatment limitations due to adverse effects and uncertain long-term risks of current pharmacotherapies. This study investigated the therapeutic potential of sepia ink (SI), a marine-derived natural complex from cuttlefish, in a scopolamine-induced ADHD-like mouse model. The chemical constituents of SI were characterized via Ultra-Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS). The behavioral assessments, histopathological examinations, flow cytometry, and complete blood counts were utilized to evaluate its effects on ADHD-like phenotypes, neuroinflammation, and immune function. Integrated transcriptomic, plasma metabolomic, and 16S rRNA sequencing were used to explore the underlying mechanisms. SI significantly alleviated hyperactivity and improved spatial learning and memory deficits. It reduced hippocampal neuronal damage, attenuated neuroinflammation, and reversed scopolamine-induced immunosuppression in spleen and thymus. SI also restored the balance of immune cell subsets in both mesenteric lymph nodes and spleen, and the peripheral blood cell counts. Multi-omics analyses suggested that the beneficial effects of SI were associated with reduced neuroinflammation, rebalanced systemic immune responses, partial correction of lipid metabolic disturbances, and restoration of gut microbiota homeostasis. Collectively, our findings indicate that SI effectively mitigates the in vivo ADHD-like impairments by coordinating immune, metabolic, and gut microbiota-related processes, thereby supporting its potential as a marine-derived therapeutic candidate for further ADHD treatment. Full article

Early post-hatch feeding strategies supplementing nutrients, particularly functional amino acids, have been proposed to enhance gastrointestinal tract (GIT) maturation and health in broilers in the post-antibiotic era. However, reported effects on performance and gut morphology remain inconsistent. Hence, this meta-analysis synthesized and clarified the efficacy pattern of supplemental FAA (Arg, Gln, Gly) evidence on growth performance, gut morphology, and lymphoid organ development. From a search spanning 2015 to September 2025, data were extracted from 23 eligible studies among 582 reports identified and pooled from five online databases. Standardized mean differences (SMDs) were calculated using Hedges’ g estimator with 95% confidence intervals, and heterogeneity was explored using subgroup and meta-regression procedures. Internal validity and reliability of included studies and publication bias were also assessed. The random-effects meta-analyses revealed that the FAA increased BWG (SMD = 1.01; p = 0.0006) and reduced feed conversion ratio (SMD = −0.45; p < 0.0001). Likewise, they enhanced intestinal architecture in both the jejunum and ileum. This was characterized by increased villus height (p < 0.05), reduced crypt depth (p < 0.05), and an elevated villus-to-crypt ratio (p < 0.0001), with the ileum exhibiting the greatest morphological response. In contrast, supplementation had no significant effect on spleen weight (SMD = 0.24; p = 0.2483) or bursa weight (SMD = 0.31; p = 0.1575). These effects, however, can be influenced by dosage used, dietary crude protein level, and broiler strain. In addition to enhancing the small intestine morphology early on, longer supplementation increased feed efficiency. Specifically, L-arginine and glycine efficaciously stimulated BWG, while L-glutamine and L-arginine enhanced morphology. Overall, early dietary supplementation with arginine, glutamine, or glycine is an effective post-antibiotic nutritional strategy to alleviate early post-hatch physiological stress and support broiler growth and intestinal development. However, to optimize nutrient utilization and sustain growth performance comparable to that achieved with standard CP diets, these FAAs in practical broiler nutrition should be strategically integrated into low-CP formulations. Full article

While current influenza vaccines often lack broad protection against antigenically drifted strains, some modified hemagglutinin (HA) protein antigens have shown promise in eliciting broadly neutralizing antibodies against conserved epitopes. During infection, the mildly acidic environment of the late endosome triggers irreversible HA conformational changes resulting in a post-fusion structure with altered antigenicity. While enhancing the stability of other structural class I viral fusion protein antigens has been instrumental in improving the effectiveness of COVID-19 and RSV vaccines, the role of HA stability in influenza vaccine immunogenicity is relatively unclear. Here, we used the nucleoside-modified mRNA-LNP platform to test engineered HA antigens with specific acid-stabilizing mutations (E47K, K58I, R106K, and K153E) in the HA stalk. All mutations increased HA acid stability, but E47K and R106K did not increase immunogenicity. K153E and K58I, but not E47K and R106K, enhanced the cell-surface expression of the HA protein in vitro. In mice, K153E- and K58I-containing mRNA-LNP vaccines elicited increased neutralizing antibody titers against homologous virus. K153E conferred greater protection than wild-type vaccine against lethal heterologous A/PR/8/34 challenge at low doses (0.5–1.0 µg), despite the absence of neutralizing antibodies against the challenge strain. K153E also elicited greater expansion of antigen-specific antibody-secreting cells (ASCs) in the bone marrow, as well as cross-reactive T follicular helper (Tfh) cells in the spleen. For the vaccines studied, increased HA expression was a stronger correlate of mRNA-LNP enhancement than increased HA stability. Full article

This narrative review describes variants of heterotopic and ectopic spleen tissue, focusing on its appearance under contrast-enhanced ultrasound (CEUS) with SonoVue (SonoVue^®; Bracco, Milano, Italy). Typical feature of splenic tissue with SonoVue is its long-lasting enhancement. The diagnosis of these splenic variants, in the vast majority of cases, has primarily been performed with CT, MRI, spleen-specific scintigraphy, or image-guided biopsy. In this review, we analyze published cases and also include our own case examples where CEUS has been used, and describe the enhancement characteristics of splenosis and atypical (intrapancreatic) accessory spleens. CEUS can provide valuable diagnostic information in patients with suspected ectopic splenic tissue, particularly when interpreted together with clinical history and complementary imaging modalities. Ultimately, ectopic splenic tissue should be considered, especially after splenectomy or splenic trauma, in cases of well-defined, hypervascularized lesions where CEUS may help avoid unnecessary invasive procedures in selected cases. Full article

Background/Objectives: Improving rabbit welfare through alternative housing systems requires a better understanding of how environmental conditions modulate physiological and immune responses at the molecular level. This study aimed to evaluate the influence of different rearing systems on the expression of genes associated with inflammation, immune regulation, and stress response in Termond White rabbits. Methods: After weaning (35 days of age), Termond White females (n = 16 per group) were allocated to five housing systems differing in space allowance and activity opportunities: hutches with outdoor runs, rabbit tractor cages with outdoor runs, single-floor indoor cages without bedding, indoor pens on deep litter, and modified indoor cages (two cages connected with a plastic pipe). At slaughter weight (2600–2900 g; 90–120 days), blood and spleen samples were collected. The relative expression of IL6, CXCR1, IL10, TGFB1, IL8, PTGS2, IL1B, and TNF was quantified by RT-qPCR using the 2^−ΔΔCt method, with ACTB and B2M as reference genes. Results: The housing system significantly affected the expression of most analysed genes in peripheral blood (IL6, CXCR1, IL1B, PTGS2, IL8, TNF, and IL10; p ≤ 0.05), whereas in the spleen significant differences were observed only for selected genes (IL1B, TNF, CXCR1, IL10, and TGFB1), with no effect detected for IL6, IL8, and PTGS2 (p > 0.05). In blood, system-dependent differences were observed for both pro-inflammatory and regulatory genes, with some housing conditions associated with higher expression of inflammatory markers. In the spleen, the response was more selective and gene-specific, suggesting tissue-dependent modulation of immune-related pathways. Conclusions: Rearing environment influences the expression of immune-related genes in Termond White rabbits; however, these effects appear to be tissue-dependent and vary among specific genes. The observed transcriptional changes suggest potential associations between housing conditions and immune responses, but further studies integrating behavioural, physiological, and protein-level data are required to confirm their relevance for animal welfare assessment. Full article

Skeletal muscle development and physiological homeostasis are profoundly influenced by environmental cues. Among these factors, ambient temperature represents a critical determinant of growth performance and metabolic adaptation in mammals. However, the effects of different ambient temperature ranges on skeletal muscle characteristics and on responses across multiple visceral tissues remain poorly understood. In this study, five ambient temperature conditions (16 °C, 20 °C, 24 °C, 28 °C, and 32 °C) were established to investigate their physiological impacts in a mouse model. Our results demonstrate that ambient temperature markedly influences growth performance and skeletal muscle phenotype. Notably, mice housed at 20 °C showed relatively preserved grip strength and a shift in myofiber cross-sectional area distribution, although these findings did not consistently indicate superior skeletal muscle development across all indices. Further analysis revealed that ambient temperature significantly modulated the expression profiles of myosin heavy chain (MyHC) isoforms in skeletal muscle. Specifically, cold exposure was associated with an upregulation of the slow-twitch-related MyHC I, whereas heat stress correlated with an elevation of the fast-twitch-related MyHC IIb. Functional assessments indicated that exposure to colder or hotter conditions was associated with impaired muscle performance, as reflected by reduced grip strength at 16 °C, 28 °C, and 32 °C, and decreased endurance capacity at 28 °C and 32 °C. Histological analyses of major visceral organs revealed no obvious structural alterations in the heart, liver, spleen, lung, or kidney across temperature conditions. However, exposure to thermal extremes (16 °C and 32 °C) significantly reduced intestinal villus height, suggesting compromised intestinal integrity under temperature stress. Collectively, these findings indicate that ambient temperature is associated with multi-tissue changes in skeletal muscle characteristics, functional performance, and intestinal morphology. This study provides new insights into how environmental temperature modulates tissue adaptation and physiological homeostasis in mammals. Full article