Search Results (816)

The Nile tilapia (Oreochromis niloticus), a key aquaculture species, displays marked sexual growth dimorphism, with males growing faster than females. This process is governed by intricate interactions between antagonistic regulators, including transcription factors, growth factors, and steroid hormones, operating through sex-specific developmental pathways. While circular RNAs (circRNAs) are known to modulate gene expression by sponging microRNAs (miRNAs), their role in teleost sex differentiation remains poorly understood. To address this gap, we profiled circRNA expression in tilapia gonads by constructing six circRNA libraries from testes and ovaries of 180 days after hatching (dah) fish, followed by high-throughput sequencing. We identified 6564 gonadal circRNAs distributed across all 22 linkage groups, including 226 differentially expressed circRNAs (DECs; 108 testis-biased, 118 ovary-biased). Functional enrichment analysis linked their host genes to critical pathways such as cAMP signaling, cell adhesion molecules, and—notably—sexual differentiation processes (e.g., estrogen signaling, oocyte meiosis, and steroid hormone biosynthesis). Furthermore, we deciphered competing endogenous RNA (ceRNA) networks, uncovering circRNA–miRNA–mRNA interactions targeting germ cell determinants, sex-specific transcription factors, and steroidogenic enzymes. This study provides the first systematic exploration of circRNA involvement in tilapia sex differentiation and gonadal differentiation, offering novel insights into the post-transcriptional regulation of sexual dimorphism. Our findings advance the understanding of circRNA biology in fish and establish a framework for future studies on aquaculture species with similar reproductive strategies. Full article

Postpartum uterine diseases such as metritis and endometritis impair reproductive performance and cause substantial economic losses in dairy cows worldwide. The multifactorial etiology, involving polymicrobial infections and complex host immune responses, poses diagnostic and therapeutic challenges. Traditional treatments rely on antibiotics, e.g., cephalosporins like ceftiofur and cephapirin, with broad-spectrum efficacy. However, emerging antimicrobial resistance, biofilm formation by pathogens such as Trueperella pyogenes, Fusobacterium necrophorum, and Escherichia coli, and bacterial virulence factors have reduced effectiveness of conventional therapies. Advances in systems biology, particularly proteomics, metabolomics, and microRNA (miRNA) profiling, have provided unprecedented insights into the molecular mechanisms underpinning uterine disease pathophysiology. Proteomic analyses reveal dynamic changes in inflammatory proteins and immune pathways, whereas metabolomics highlight shifts in energy metabolism and bacterial–host interactions. Furthermore, miRNAs have critical roles in post-transcriptional gene regulation affecting immune modulation, inflammation, and tissue repair, and also in modulating neutrophil function and inflammatory signaling. Uterine inflammation not only disrupts local tissue homeostasis but also compromises early embryo development by altering endometrial receptivity, cytokine milieu, and oocyte quality. Integration of multi-omics approaches, combined with improved diagnostics and adjunct therapies—including micronutrient supplementation and immunomodulators—offers promising avenues for enhancing disease management and fertility in dairy herds. This review synthesizes current knowledge on proteomics, metabolomics, and miRNAs in postpartum uterine diseases and highlights future directions for research and clinical applications. Full article

The gut microbiome plays a critical role in host physiology and adaptation, shaped by both intrinsic host factors and extrinsic environmental conditions. In this study, we investigated the influence of habitat type and geographical isolation on gut microbial communities in habitat-isolated populations of the euryhaline cichlid Etroplus suratensis, which inhabit freshwater and brackish water environments. Using 16S rRNA gene amplicon sequencing, we compared microbial assemblages in fish guts and their corresponding habitats to assess patterns of community divergence. Alpha and beta diversity analyses revealed significant differences in microbial composition between gut and water samples, with limited overlap, particularly in brackish water, indicating strong host-mediated filtering of environmental microbiota. Notably, brackish and freshwater habitats harbored 2244 and 3136 unique water-associated taxa, respectively, while only 36 and 426 taxa were shared between water and gut in each habitat. Despite habitat divergence, 59 microbial taxa were consistently shared across gut samples from both populations, indicating the existence of a conserved core microbiome that likely fulfills essential functional roles. These findings support the notion that the fish gut serves as a selective ecological niche, enabling the persistence of functionally relevant microbes while restricting the entry of environmental transients. Moreover, the observed divergence in gut microbiota across habitats, coupled with a shared core, highlights the interplay between local adaptation and conserved host–microbe associations, with potential implications for understanding microbial contributions to vertebrate ecological diversification and allopatric speciation. Full article

Candida parapsilosis has emerged as a prominent cause of nosocomial candidemia, particularly among critically ill patients. The increasing prevalence of fluconazole-resistant C. parapsilosis (FR-Cp) poses major therapeutic challenges, especially in resource-limited settings. We conducted a retrospective study of 144 patients with C. parapsilosis candidemia admitted to two post-surgical ICUs at a Brazilian tertiary cardiothoracic hospital between 2016 and August 2024. Demographic, clinical, microbiological, and therapeutic data were analyzed. Predictors of 30-day mortality were identified through multivariate logistic regression. The incidence density of C. parapsilosis candidemia ranged from 2.93 to 8.31 per 1000 hospitalizations. Fluconazole resistance was identified in 81% of isolates. Overall 30-day mortality was 55%. Independent risk factors for mortality included cardiopathy (OR: 19.36, p = 0.006), higher SOFA scores (OR: 1.54, p = 0.003), parenteral nutrition (OR: 29.77, p = 0.013), and dialysis (OR: 6.59, p = 0.043), while longer treatment duration was protective (OR: 0.81, p < 0.001). Fluconazole resistance was not independently associated with increased mortality. In this cohort of critically ill patients, C. parapsilosis candidemia was associated with high mortality and a high prevalence of fluconazole resistance. Clinical outcomes were mainly driven by host-related and therapeutic factors rather than antifungal resistance alone. Full article

Temperature is a critical factor influencing fish health and aquaculture success. This study investigates the physiological, histological, and microbiota responses of juvenile Schizothorax grahami to chronic thermal stress across six temperature treatments. We found that exposure to temperatures exceeding 27 °C resulted in complete mortality in juvenile S. grahami, with the upper thermal tolerance range between 24 °C and 27 °C. Chronic thermal stress caused a significant decline in serum glucose (Glu), triglycerides (TG), and total cholesterol (TC) at 24 °C, indicating rapid energy depletion, while reduced serum enzyme activity of catalase (CAT) and total superoxide dismutase (T-SOD) at 24 °C group further reflected a decrease in antioxidant capacity. Histological examination revealed adaptive intestinal villus hypertrophy with increased length and muscularis thickness at temperature under 24 °C. Furthermore, the relative abundance of Cetobacterium and Fusobacteriota suggested either adaptive responses or stress-related dysbiosis that may contribute to weakened host immune function. Overall, our findings highlight the vulnerability of juvenile S. grahami to rising temperatures, with moderate thermal stress inducing adaptive responses, while higher temperatures impair metabolism, gut integrity, microbial health, and may even lead to lethality. These results underscore the need for effective conservation strategies to protect this critically endangered species in the face of climate change. Full article

Halotolerant endophytic fungi (HEFs) represent a critical biological resource in mitigating plant salt–alkali stress, demonstrating remarkable adaptability across diverse ecological environments. This comprehensive review analyzes 150 scientific publications, revealing HEFs’ multifaceted mechanisms of plant stress tolerance. Inhabiting over 30 host plant species without causing pathogenic effects, these fungi enhance plant resilience through sophisticated physiological strategies. Key findings highlight HEFs’ ability to modulate ionic homeostasis, elevate antioxidant capacities, and stimulate plant growth under saline conditions. The research unveils the potential of HEF metabolites as biostimulants and explores their co-evolutionary hypotheses with host plants. Despite promising laboratory and field validations, significant challenges remain in HEFs’ practical agricultural applications, including environmental factor interactions and biotechnological ethical considerations. Future research directions emphasize deeper investigations into HEFs’ ecological adaptability and microbiological interactions to unlock their full agricultural potential. Full article

Plesiomonas shigelloides, a Gram-negative bacterium prevalent in aquatic environments and also frequently isolated from livestock and poultry, was investigated through integrated whole-genome sequencing and functional analyses. We deciphered the pathogenic mechanisms of P. shigelloides CA-HZ1, a highly virulent strain isolated from a novel piscine host, revealing a complete genome assembly with a 3.49 Mb circular chromosome and 311 kb plasmid housing 3247 predicted protein-encoding genes. Critical genomic features included 496 virulence factors and 225 antibiotic resistance genes. Pathogenicity analysis indicated that P. shigelloides was responsible for disease outbreaks. Antimicrobial susceptibility tests showed resistance to various drugs, such as kanamycin, erythromycin, and penicillin. Histopathological examination showed significant alterations in the infected hosts. Quantitative real-time PCR (qRT-PCR) was carried out to analyze immune-related gene (IL-6, IL-1β, IL-21, STAT1, and HSP70) levels in liver and intestinal tissues, demonstrating the potent immunity triggered by P. shigelloides infection. An analysis of the liver transcriptome revealed that P. shigelloides has the potential to influence the cellular composition, molecular functions, and biological processes. Collectively, this study describes the genomic basis underlying both the pathogenic potential and hypervirulence of P. shigelloides CA-HZ1, establishing a foundational framework for investigating its broad host tropism and immune response. Full article

Background/Objectives: Metal–ceramic crowns may be constructed using different techniques and coping materials. A systematic review analysing the coping material, method of construction, and instruments used for measuring the metal–ceramic crown marginal gap has not been completed. The aim of this systematic review was to appraise the literature relating to the instruments used for the in vitro marginal gap measurement of single pre-cemented metal–ceramic crowns and assess whether the crown coping material and method of coping construction influence the marginal gap. Methods: A systematic search was performed in November 2024 across the EBSCO Host, Scopus, PubMed, and Web of Science databases, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and specific eligibility criteria. The Joanna Briggs Critical Appraisal Checklist was used to assess article quality. Results: Fourteen studies evaluated marginal gaps in 402 crowns using the following techniques: direct view microscopy (eight studies), replica techniques (three studies), scanning electron microscopy (two studies), and profilometry (one study). The mean marginal gap for all the metal–ceramic crowns across all the studies was 65.97 ± 32.58 µm. The pre-cementation mean marginal gaps showed no significant difference between Computer-Aided Design–Computer-Aided Manufacturing (CAD-CAM) milled copings (87.95 ± 26.35 µm) and conventionally cast copings (90.45 ± 24.37 µm) (t = −0.197, p = 0.847). The mean marginal gaps varied significantly (F = 11.34, p < 0.001) by coping material: cobalt–chromium (Co-Cr) led to 84.28 µm, nickel–chromium (Ni-Cr) led to 70.98 µm, titanium led to 50.18 µm, and noble metal alloys led to 27.90 µm. Six studies addressed confounding factors and followed a standardised approach for measuring marginal gaps. Conclusions: Direct view microscopy was the most commonly used instrument for measuring the marginal gaps of single pre-cemented metal–ceramic crowns, yielding the smallest reported mean marginal gap of 75.00 ± 26.87 µm. Metal–ceramic crowns constructed with noble metal alloys exhibited the lowest mean marginal gaps. Metal–ceramic crowns constructed using conventional casting techniques presented similar marginal gaps to CAD-CAM crowns. Full article

The dengue virus (DENV) exploits host cell exosome pathways to disseminate and evade immunity. However, the host factors enabling this process remain poorly defined. Here, we demonstrate that DENV infection robustly induces expression of the short isoform of Reticulon 3 (RTN3S) in hepatic (Huh7) and monocytic cells, and that RTN3S is a critical driver of infectious exosome biogenesis. RTN3S physically associates with double-stranded viral RNA and the DENV non-structural protein 3 (NS3) in infected cells, indicating its integration into the viral replication complex. Loss of RTN3 markedly reduced exosome production and the exosomal export of viral RNA and proteins, demonstrating that RTN3S is required for efficient exosome-mediated viral release. Conversely, overexpression of full-length RTN3S dramatically increased the release of infectious virus-containing exosomes; truncation of the RTN3S C-terminal domain abolished this enhancement, confirming the essential role of the C-terminus in RTN3S’s pro-viral exosomal function. In DENV-infected monocytes, we observed a shift toward a CD16-positive intermediate phenotype, accompanied by the upregulation of genes involved in vesicle biogenesis and stress response. These infected monocytes also secreted higher levels of inflammatory cytokines. Similarly, monocytes from Dengue patients exhibited high RTN3 expression, which correlated with an expansion of intermediate (CD16⁺) subsets and enriched expression of vesicle trafficking machinery genes. These findings reveal a previously unrecognized mechanism by which DENV hijacks RTN3S to promote the formation of infectious exosomes, thereby facilitating viral dissemination and immune evasion. RTN3S thus represents a novel element of the Dengue pathogenesis and a potential target for host-directed antiviral strategies. Full article

Aging is a complex biological process influenced by internal and external factors, with diet and gut microbiota emerging as pivotal, interconnected modulators. This review explores their triangular relationship, emphasizing how they dynamically interact to shape health across the lifespan. Aging involves notable shifts in gut microbiota, including reduced diversity, increased pro-inflammatory taxa, and impaired production of key metabolites, like short-chain fatty acids. These changes contribute to systemic inflammation, immune-senescence, and age-related conditions, such as cognitive decline and metabolic disorders. Diet, particularly Mediterranean and plant-based patterns, plays a critical role in modulating gut microbiota by enhancing beneficial microbes and their metabolic functions. In contrast, Western-style diets rich in saturated fats and processed foods promote dysbiosis and accelerate aging. The review synthesizes evidence from human studies, animal models, and interventions to show how microbiota mediates diet-driven effects on aging. It also explores the role of specific nutrients, fiber, omega-3 fatty acids, and polyphenols in influencing microbial and host aging biology. Emerging therapies, including probiotics, prebiotics, and precision nutrition, show promise for promoting healthy aging by restoring microbial balance. However, gaps remain, including the need for long-term, age-specific studies, standardized microbiome protocols, and integrated omics approaches to support targeted longevity strategies. Full article

Multidrug-resistant bacterial infections pose a severe global health threat, highlighting the urgent need for innovative therapeutic options beyond traditional antibiotics. Phage therapy, which employs bacteriophages to infect and eradicate pathogenic bacteria, specifically offers a promising solution. However, the lack of well-characterized therapeutic phages has limited their broader clinical use. A critical aspect of activating the lytic potential of dormant prophages involves the strategic manipulation of transcription factor binding sites (TFBS), which function as pivotal regulatory nodes governing the transition between lysogenic dormancy and lytic activation. Our platform utilizes advanced bioinformatics tools to accurately identify and analyze TFBS, facilitating the targeted redesign or replacement of these sites to disrupt host-mediated repression. By systematically simulating modifications of these regulatory ‘switches,’ our platform computationally predicts reduced repressor activity, suggesting the potential for prophage activation and bacterial cell lysis. This novel methodology not only broadens the spectrum of therapeutic bacteriophages but also establishes a basis for individualized phage-based therapies, presenting a robust strategy to address the escalating challenge of antibiotic-resistant infections. By enabling the precise identification and engineering of TFBS, our platform signifies a transformative advancement in phage biology, effectively bridging the divide between computational analysis and therapeutic application. Full article

This paper presents a case study of the Honduran electricity system and evaluates the technical impact of integrating distributed generation through modeling and simulation using Pandapower, (version 3.1.0) an open-source Python tool. A multi-criteria methodology was applied to select connection nodes considering the voltage sensitivity (∆V/MW), loss factor, available thermal capacity (headroom), and hosting capacity. The analysis focused on voltage stability, power losses, and line loading under various distributed generation scenarios. This methodology prioritized buses with critical voltages and significant loads. The case study model included official data from the Honduran National Dispatch Center. The simulations included a redispatch scheme for conventional generators to maintain power balance in all scenarios (20–100% distributed generation profiles), using GEN (controllable output) and SGEN (fixed output) components. The results show that with 50% distributed generation relative to local demand, voltages at critical buses improved by up to 0.14 p.u. Total active losses decreased by 9%, and reactive losses decreased by 44%. Additionally, indirect improvements were observed in non-intervened buses, as well as load relief in lines and transformers. These results confirm that strategic distributed generation injections combined with redispatch can improve supply quality and operational efficiency in weak and radial network topologies. The proposed methodology is scalable and able to be replicated in other power systems, providing technical input for energy planning and renewable energy integration in developing countries. Full article

The rational design of advanced functional materials with tailored fluorescence hinges on a profound understanding of the complex interplay between a molecule’s intrinsic structure and its local solid-state environment. This work systematically investigates these factors by employing a dual approach that combines targeted molecular synthesis with the subsequent modulation of the fluorophore’s properties within polymer matrices. First, a series of phenylhydrazone derivatives was synthesized, providing compounds with intense, solid-state fluorescence in the blue spectrum (421–494 nm). It was demonstrated that their photophysical properties were intricately linked to the substituent’s nature, which simultaneously modulated their intramolecular electron density and conformational rigidity while also governing their specific intermolecular packing in the solid state. Subsequently, we investigated the role of the supramolecular environment by embedding two fluorophores with distinct electronic profiles into electrospun poly (N-vinylpyrrolidone) (PVP) and polystyrene (PS) matrices. Our results reveal that the polymer matrix is not a passive host but an active component; it governs dye aggregation, induces significant blue shifts, and most critically, can impart exceptional thermal stability. Specifically, the PVP matrix shielded the embedded dyes from thermal quenching, maintaining robust fluorescence up to 100 °C. By combining molecular-level synthesis with matrix-level engineering, this work demonstrates a powerful strategy for the rational design of emissive materials, where properties like color and operational stability can be deliberately tuned for demanding applications in optoelectronics and sensing. Full article

Viral infection is a significant cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation (Allo-HSCT), largely due to its impact on and interaction with immune reconstitution. Both innate and adaptive immunity are essential for effective viral control, yet their recovery post-transplant is often delayed or functionally impaired. Emerging evidence suggests genetic variation, particularly polymorphisms in the IL28B gene (encoding IFN-λ3), as a critical factor influencing the quality and timing of immune responses during the early post-transplant period. This review explores the role of IL28B polymorphisms in shaping antiviral immunity, in general, as well as after Allo-HSCT. IL28B variants have been implicated in modulating interferon-stimulated gene (ISG) expression, natural killer (NK) cell activity, and type I/III interferon signaling, all central components of innate immune defense against viral infections. Furthermore, IL28B polymorphisms, particularly rs12979860, have been shown in both general populations and limited HSCT cohorts to alter T cell response and interferon production, affecting reactivation and clearance of multiple viruses such as cytomegalovirus (CMV), hepatitis B virus (HBV), hepatitis C virus (HCV), Epstein–Barr virus (EBV), COVID-19, and BK polyomavirus (BKPyV) as well as Graft vs. Host disease, thereby affecting adaptive immune reconstitution and long-term viral control. Understanding how IL28B genotype alters immune dynamics in transplant recipients could enhance risk stratification for CMV and other diseases and inform personalized prophylactic or therapeutic strategies. Therefore, this review highlights IL28B as a promising biomarker and potential immunoregulatory target in the management of viral infection post-Allo-HSCT. Full article

Candida species commonly secrete aspartic peptidases (Saps), which are virulence factors involved in nutrient acquisition, colonization, tissue invasion, immune evasion and host adaptation. However, the regulation of Sap production remains poorly characterized in emerging, widespread and multidrug-resistant members of the Candida haemulonii clade (C. auris, C. haemulonii, C. haemulonii var. vulnera and C. duobushaemulonii). This study investigated the influence of temperature, pH and protein substrate on Sap production using bloodstream isolates of the C. haemulonii clade. Sap activity was initially assessed using the enzyme coefficient (Pz) in fungal cells grown on yeast carbon base (YCB) agar supplemented with bovine serum albumin (BSA) to determine optimal conditions for enzymatic production. C. auris and C. duobushaemulonii exhibited the highest Sap activity at 96 h, pH 4.0–5.0, and 37 °C, whereas C. haemulonii and C. haemulonii var. vulnera displayed more variable and isolate-dependent profiles. Sap production was markedly suppressed at pH 6.0. The addition of pepstatin A, an inhibitor of aspartic peptidases, abolished Sap activity and impaired fungal growth in a dose-dependent manner, confirming both the enzymatic identity and its critical role in nitrogen acquisition. Conversely, YCB supplemented with an inorganic nitrogen source (ammonium sulfate) supported fungal growth but did not induce Sap production. To explore substrate specificity, YCB was supplemented with a panel of proteins. Serum albumins (bovine and human) induced the highest Sap production, followed by globulin, gelatin, hemoglobin, collagen and immunoglobulin G, while elastin and mucin elicited the lowest Sap production. Isolate-specific preferences for protein substrates were observed. Finally, fluorometric assays using a Sap-specific fluorogenic peptide substrate confirmed the presence of Sap activity in cell-free supernatants, which was consistently and entirely blocked by pepstatin A. These findings highlight inter- and intraspecies variability in Sap regulation among C. haemulonii clade, stressing the critical roles of substrate availability, pH and temperature in shaping fungal adaptation to host environments. Full article