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PubMed2026

Transcriptomic responses of gill and intestinal tissues in Nile tilapia (Oreochromis niloticus) to bacterial infection following sequential nanoimmersion and hydrogel-based multivalent vaccination.

Bacterial pathogens, including Flavobacterium oreochromis, Aeromonas veronii, Streptococcus agalactiae, and Edwardsiella tarda, represent major infectious threats to Nile tilapia (Oreochromis niloticus). A multivalent vaccination strategy integrating cationic nanoemulsion immersion with oral hydrogel boosters was developed to investigate tissue-specific immune responses at the transcriptomic level. Gill tissues were collected following immersion challenge and intestinal tissues following intraperitoneal injection challenge, reflecting the physiologically relevant infection biology of each pathogen and the mechanistic rationale of each delivery platform. RNA sequencing (RNA-seq) generated high-quality datasets (mapping rate > 81.64%) with strong concordance to quantitative real-time PCR (qRT-PCR) validation (r = 0.83). Comparative transcriptomic analysis revealed distinct yet complementary immune signatures between tissues. Gill transcriptomes were enriched in phagosome, focal adhesion, extracellular matrix-receptor interaction (ECM-receptor interaction), and cytokine-cytokine receptor interaction pathways, accompanied by increased expression of major histocompatibility complex class I/II (MHC class I/II), mannose receptor, αVβ3 integrin, and calnexin, indicating innate activation, enhanced phagocytic capacity, epithelial barrier reinforcement, and adaptive immune coordination. Intestinal transcriptomes showed predominant enrichment of adaptive immune pathways, including the intestinal immune network for immunoglobulin (Ig) production, Forkhead box O (FoxO) signaling, and mitogen-activated protein kinase (MAPK) signaling, with increased expression of T-cell receptor (TCR), inducible T-cell co-stimulator ligand (ICOS-L), C-X-C chemokine receptor type 4 (CXCR4), and polymeric immunoglobulin receptor (pIgR), reflecting T and B cell coordination, lymphocyte trafficking, and mucosal immunoglobulin transport, alongside innate engagement through phagosome pathway enrichment. Shared upregulation of MHC class II, B-cell receptor (BCR) signaling, integrin alpha M (ITGAM), and immunoglobulin-associated components across both tissues suggests coordinated mucosal immune activation through a conserved immune module, warranting direct experimental validation. Collectively, these findings provide transcriptomic evidence that this vaccination strategy elicits an integrated, tissue-specialized immune response, advancing mechanistic understanding of gill and intestinal immunity in vaccine-induced protection of teleost fish.

Animals↗

PubMed2026

Assessing the threat of Bacillus cereus: From toxin characterization to modern detection strategies.

Bacillus cereus is a spore-forming pathogen responsible for both diarrheal and emetic foodborne illnesses worldwide. Its significance in food safety has received growing attention. Recent advances, including the discovery of novel virulence factors and the development of emerging detection technologies, have provided new insights into its pathogenic mechanisms and surveillance strategies. This review critically examines the global burden of B. cereus infections, and molecular mechanisms of its major virulence factors, and the performance characteristics of current detection knowledge gaps such as the viable-but-non-culturable state and regulatory blind spots for emetic toxins, and discuss unresolved challenges in clinical management. By integrating epidemiological, microbiological, and technological perspectives with critical lens, this review aims to provide a valuable reference for future research and food safety practices.

Bacillus cereus↗

PubMed2026

Dissemination of blaKPC-3-harbouring Klebsiella pneumoniae across ST48 and ST628 in multiple healthcare facilities in the Republic of Korea.

Klebsiella pneumoniae carbapenemase-3 (KPC-3) remains rare in South Korea, where KPC-2 is the dominant carbapenemase, making the repeated detection of a concentrated blaKPC-3 signal over five years notable. We performed genomic analyses of blaKPC-3-harbouring K. pneumoniae from a regional healthcare network. Two chromosomally distinct lineages with concordant capsule loci (ST628/KL15 and ST48/KL62) presented multidrug-resistant phenotypes, and the virulence-associated loci were confined to ST48. Single-nucleotide polymorphism (SNP) analyses revealed near-clonal relatedness within lineages, with 0-38 pairwise SNPs among ST628 isolates and 8 SNPs between the two ST48 isolates. Core-genome multilocus sequence typing (cgMLST) supported this structure, as ST628 isolates were assigned to complex type 19149 with 0-7 allelic differences, and ST48 isolates were assigned to complex type 19150 with 5 allelic differences. These patterns support vertical spread via clonal expansion across multiple facilities. Despite substantial chromosomal separation, most isolates carried the same IncFII(K) plasmid backbone and blaKPC-3, and they were nearly indistinguishable from a plasmid previously reported in South Korea. One isolate carried blaKPC-3 on a distinct multireplicon IncFIB(K)/IncFII(K) plasmid, indicating that the signal was not confined to a single plasmid backbone. In both plasmids, blaKPC-3 was embedded within Tn4401b. These findings indicate that a rare blaKPC-3 genotype can persist regionally through sustained clonal dissemination and that cross-lineage linkage is compatible with past horizontal transfer involving a conserved plasmid. These findings underscore the need for subtype-resolved, regionally coordinated genomic surveillance in connected healthcare networks to detect uncommon carbapenemase variants early.

Klebsiella pneumoniae↗

PubMed2026

Population-level impact of HPV vaccination: a global systematic review of ecological, cross-sectional, and cohort studies.

BACKGROUND: Human papillomavirus (HPV) causes approximately 4.5% of cancers globally, with the highest burden in low- and middle-income countries (LMICs). Since their introduction in 2006, HPV vaccination programs have led to substantial declines in HPV-related outcomes, although impact varies across settings. RESEARCH DESIGN AND METHODS: We conducted a systematic review to evaluate the population-level impact of HPV vaccination on HPV infection, cervical intraepithelial neoplasia grade 2 or higher (CIN2+), genital warts, invasive cervical cancer (ICC), and oropharyngeal cancer (OPC), and examined the influence of coverage, age at initiation, and vaccine type. The review followed PRISMA 2020. RESULTS: Of 13,549 records screened, 63 were included: 9 assessed HPV infection, 24 on CIN2+, 25 on genital warts, and 7 on ICC. Greatest reductions were observed in settings with at least 70% coverage and early vaccination prior to sexual debut, typically achieved through school-based programs. Reported declines ranged from 58-100% for HPV infection, 30-88% for CIN2+, 60-90% for genital warts, and 70-88% for ICC. CONCLUSIONS: HPV vaccination offers strong protection, especially when delivered early and at high coverage within schools. Expanding access and prioritizing underserved populations are essential to achieving global cancer prevention goals. Limitations include heterogeneity across designs, outcome definitions, and follow-up.

Humans↗

PubMed2026

Changes in sexual behavior among women in studies evaluating the dapivirine vaginal ring for HIV prevention.

BACKGROUND: Access to novel HIV prevention technologies often raise concerns of risk compensation. This analysis examined changes in the sexual behaviors of MTN 020/ASPIRE participants, a placebo controlled randomized control trial, who subsequently enrolled in MTN-025/HOPE, an open-label extension using the dapivirine vaginal ring. METHODS: Both studies enrolled healthy, sexually active, HIV-negative women from Malawi, South Africa, Uganda and Zimbabwe. Longitudinal data on participants' sexual behaviors, specifically sex with a nonprimary partner (past 3 months), and use of male or female condoms at the last vaginal sex act were compared between ASPIRE and HOPE. Conditional and mixed ordinal logistic regression models evaluated associations between study and sexual behaviors at enrollment, and quarterly over the first 12 months. RESULTS: Of the 2629 individuals enrolled in ASPIRE, 1456 (55%) participated in HOPE. At enrollment, the proportion of participants who reported sex with a nonprimary partner and condom use at last vaginal sex act did not differ by study. Across all quarterly follow-up visits, sex with a nonprimary partner was more common in HOPE (13.9-18.7%) than ASPIRE (10.7-12.6%); adjusted OR 1.47, 95% CI 1.24-1.75, P < 0.001. There was no difference in condom use at the last vaginal act across all quarterly follow-up visits between ASPIRE (36.5-42.7%) and HOPE (43.6-46.7%); adjusted OR 1.05, 95% CI 0.94-1.18. CONCLUSION: More women reported sex with nonprimary partners in HOPE, with little change in condom use over time between the two studies. Understanding behavior changes during PrEP use allows for tailored, holistic reproductive health programming.

Humans↗

PubMed2026

O'nyong-nyong virus adaptive mutations in non-structural protein 1 and 3 enhance RNA replication and overcome FHL1 requirement.

Arthritogenic alphaviruses, like o'nyong-nyong virus (ONNV), cause debilitating musculoskeletal diseases and are geographically expanding. To predict their emergence, we seek to better understand evolutionary mechanisms that enable changes in virus tropism. Here, we identify adaptive mutations in the ONNV non-structural proteins (nsPs) that arose during cellular serial passaging and enabled ONNV to infect non-permissive Lunet cells. Using shotgun proteomics, we show that this human hepatoma cell line lacks the four-and-a-half-LIM domain protein 1 (FHL1), an essential host factor in ONNV RNA replication. Individual single nucleotide mutations in the nsP1 ring-aperture membrane-binding and oligomerization domain, the nsP3 macrodomain, and the nsP3 opal stop codon overcome FHL1 deficiency in Lunet cells by enhanced RNA replication. These findings demonstrate how subtle genomic changes in nsPs can profoundly influence alphavirus replication and tropism.

LIM Domain Proteins↗

PubMed2026

Parallel evolutionary trajectories rewire enteropathogenic Escherichia coli adhesion to restore host attachment.

Enteropathogenic Escherichia coli (EPEC) causes disease in children, presenting as chronic diarrhea that can impair physical and cognitive development. The attachment of typical EPEC (tEPEC) to the gut epithelium via bundle-forming pili (BFP) is a key factor in its virulence. Yet, infections by atypical EPEC (aEPEC), which lack BFP, have become increasingly common. To investigate how aEPEC recover host-attachment in the absence of BFP, we performed experimental evolution using a non-adherent E. coli, constructed to mimic the ancestor of aEPEC, and selected adherent progeny. Highly adherent variants evolved through phase-variable activation of type I fimbriae (T1F), followed by two alternative trajectories: bacterial filamentation, which increases T1F avidity, or point mutations in the T1F adhesin FimH that enhance ligand affinity. Extending our analysis to the genomes of 327 aEPEC strains isolated from infected patients revealed that similar FimH mutations are common. We further demonstrated experimentally that these naturally occurring variants often increase epithelial-attachment. Our findings implicate T1F in aEPEC pathogenesis and suggest it may be clinically relevant for anti-adhesion therapy. More broadly, these results indicate that impaired host-attachment can be rapidly compensated by upregulating and optimizing an alternative adhesin, and that combining experimental evolution with comparative genomics can reveal evolutionary trajectories occurring in nature.

Bacterial Adhesion↗

PubMed2026

Whole-transcriptome RNA sequencing and ceRNA network analyses provide novel insights into the antibacterial immune response of Hippocampus abdominalis against Vibrio harveyi.

Long non-coding RNAs (lncRNAs) stand as newly-arisen molecular types that exert regulatory effects, able to operate as competitive endogenous RNAs (ceRNAs) to engage microRNAs (miRNAs) in interaction, resulting in the recovery of target mRNA expression and activity. Increasing evidences indicate that the ceRNA network affects various biological processes in mammals, including development, cellular differentiation, metabolism, immune response, and disease pathogenesis. In teleost fish, the lncRNA-miRNA-mRNA regulatory networks have been reported occasionally. However, up to now, the roles of lncRNAs in the big-belly seahorse (Hippocampus abdominalis) remains unclear. In this study, we reported for the first time, via whole-transcriptome RNA sequencing, the lncRNA mediated ceRNA regulatory network in Vibrio harveyi-infected H. abdominalis. A total of 4197 differentially expressed mRNAs (DE-mRNAs), 1317 DE-lncRNAs, and 183 DE-miRNAs were identified. Furthermore, the crosstalk between miRNAs and lncRNAs as well as between miRNAs and mRNAs was inferred based on the negative correlations between miRNAs and their target lncRNAs/mRNAs. A core immune associated lncRNA-miRNA-mRNA putative regulatory network was thus constructed, comprising 211 lncRNA-miRNA and 224 mRNA-miRNA pairs. In conclusion, our findings provide an integrative overview of the ceRNA regulatory networks on the underlying immune responses to V. harveyi infection in the big-belly seahorse, and offer a solid theoretical foundation for the comparative immunological research of teleost fish.

Animals↗

PubMed2026

Emerging hantavirus risks in mass gatherings: epidemiology, diagnostic challenges, and outbreak preparedness.

Hantaviruses are emerging rodent borne zoonotic pathogens of increasing global public health concern because of their high mortality, expanding ecological distribution, and potential for international dissemination. Although traditionally associated with sporadic rural outbreaks, recent ecological disruption, climate variability, urbanization, and increased global mobility have heightened concerns regarding hantavirus risks in mass gathering settings. This review critically examines the epidemiology, transmission uncertainty, diagnostic and surveillance challenges, and preparedness strategies related to hantavirus infections in the context of mass gatherings, including religious events, refugee settlements, cruise tourism, sporting events, and temporary accommodations. Particular emphasis is placed on the 2026 multinational cruise ship associated outbreak linked to the MV Hondius, which highlighted vulnerabilities related to delayed diagnosis, international passenger dispersal, and uncertainties surrounding possible human to human transmission of Andes virus. Current evidence indicates that hantavirus transmission occurs primarily through inhalation of aerosolized rodent excreta; however, controversies regarding limited interpersonal transmission, environmental persistence, and asymptomatic infections continue to complicate risk assessment and outbreak preparedness. Diagnostic limitations, underreporting, insufficient environmental surveillance, and lack of mass gathering specific preparedness frameworks remain major public health challenges, especially in resource limited settings. Strengthening proactive preparedness through integrated One Health approaches, ecological surveillance, genomic monitoring, AI driven epidemic intelligence, and coordinated international response systems is essential for mitigating future risks. The review emphasizes the urgent need for multidisciplinary research and evidence based policy development to improve global preparedness against emerging hantavirus associated threats in increasingly interconnected mass gathering environments.

Humans↗

PubMed2026

Liver Cancer Risk and Incidence Attributable to Human Immunodeficiency Virus: A Meta-Analysis and Population-Attributable Modeling Study of Over 1.2 Million Individuals.

HIV-induced immune suppression and chronic inflammation elevate the risk of cancer progression. We conducted a systematic review and meta-analysis of studies published between January 1, 1984 and October 13, 2023 to assess the association between HIV infection and liver cancer. People living with HIV (PLHIV) had a higher risk (pooled relative risk = 3.36, 95% CI: 2.72-4.15). The global PAF for HIV-attributed liver cancer was 1.43% in 2019, with a three-fold increase over the past 30 years. The Asia-Pacific region recorded the second highest new cases of HIV-attributed liver cancer in 2019, and the highest age-standardized incidence rate (ASIR) in Eastern and Southern Africa. Particularly, the ASIR of HIV-attributed liver cancer increased rapidly in Eastern Europe and Central Asia, with the highest estimated annual percentage change reaching 22.98%. PLHIV have an increased risk and incidence of liver cancer. In regions with high burden of HIV-attributed liver cancer, it is essential to integrate prevention and effective treatment for HIV, viral hepatitis, alcoholic liver disease, nonalcoholic steatohepatitis, and liver cancer.

Humans↗

PubMed2026

First identification and molecular subtyping of Blastocystis spp. in donkeys in Aksaray province, Türkiye.

Blastocystis is a common intestinal protist worldwide that can infect humans and animals. Although its molecular epidemiology in Türkiye is mostly focused primarily on humans and livestock, equids have received limited attention despite their traditional roles and frequent contact with humans and other animals in rural environments. This study aimed to determine the molecular prevalence and subtype (ST) distribution of Blastocystis spp. in donkeys in Aksaray Province, providing the first molecular data on donkeys in Türkiye. A total of 182 fresh fecal samples were collected from donkeys in nine villages within Aksaray province. Genomic DNA was extracted, and the small subunit ribosomal RNA (SSU rRNA) gene fragment of Blastocystis spp. was amplified via PCR analysis. Positive isolates were sequenced bidirectionally for identification and subsequent phylogenetic analysis of Blastocystis in donkeys. The overall molecular prevalence of Blastocystis spp. in donkeys was 4.4% (8/182). The infection rate was higher in young donkeys (under 3 years old; 8.33%) than in adults (3 years or older; 2.46%). However, this difference was not statistically significant. Sequence analysis of the positive PCR products revealed the presence of one known livestock-specific subtype, ST10. Phylogenetic analysis showed that the ST10 isolates characterized in this study clustered with isolates identified from different hosts. This study provides the first molecular data on Blastocystis presence in donkeys in Türkiye. The exclusive detection of ST10 suggests potential cross-species transmission, likely facilitated by the traditional practice of co-housing donkeys with other animals in confined barns. These findings indicate that donkeys may contribute to Blastocystis transmission, underscoring the importance of a "One Health" approach in future epidemiological surveillance.

Animals↗

PubMed2026

Characterization and application potential of two newly isolated phages targeting the prevalent multidrug resistant Salmonella serovars in China.

The escalating global threat of multidrug resistant (MDR) Salmonella, a foodborne pathogen with animal-derived foods serving as the primary transmission vehicle, underscores the urgent need for effective lytic phages for biocontrol. From 142 environmental and farm samples in Shandong Province, we isolated 103 phages active against MDR S. Enteritidis and S. Typhimurium, which were the most prevalent Salmonella serovars in China. Two Siphoviridae phages vB-SenS-S1 and vB-SenS-SEC2 were selected for further study. With optimal multiplicities of infection (MOIs) of 10-2 (vB-SenS-S1) and 10-5 (vB-SenS-SEC2), both phages exhibited a 20 min latent period, yielding burst sizes of 52 and 37 PFU/cell, respectively. They also demonstrated stability across a range of temperatures (50-60 °C), pH levels (5-11), and after 1 h of UV exposure. Genomic analysis identified vB-SenS-S1 (43,002 bp, 47.04% GC) and vB-SenS-SEC2 (42,948 bp, 47.65% GC) as novel double-stranded DNA phages. Functional annotation confirmed the presence of genes essential for structural assembly, host lysis, and DNA replication/metabolism, and also verified the absence of resistance, virulence, and lysogeny-associated genes. Both phages vB-SenS-S1 and vB-SenS-SEC2 exhibited synergy with colistin and tetracycline. The synergy with colistin was particularly potent, leading to complete bacterial eradication in vitro. The in vivo therapeutic efficacy was further validated in both Galleria mellonella larvae and murine models of MDR Salmonella infection. Combination therapy with vB-SenS-SEC2 and colistin not only dramatically increased survival but also achieved a significant reduction in bacterial burden across multiple visceral organs of infected mice. Moreover, vB-SenS-S1 (108 PFU/mL) completely inhibited MDR Salmonella on chicken meat at 4 °C and -20 °C when initial contamination was ≤103 CFU/mL. This study not only expands the diversity of Salmonella phages but also highlights their potential as biocontrol agents in both clinical veterinary use and food decontamination, thereby enhancing food quality and safety at both the meat production source and the terminal product.

Animals↗

PubMed2026

Systematic review of the mutations in the active antigenic site Ø of the prefusion F protein of the Respiratory Syncytial Virus (RSV) following the implementation of monoclonal antibody prophylaxis.

BACKGROUND: Monoclonal antibody (mAb) nirsevimab, which targets the antigenic site Ø of the prefusion F protein (pre-F) of RSV, was introduced for RSV prophylaxis in several countries. METHODS: A systematic search was conducted between January 1, 2022, and July 31, 2026 for studies analyzing substitutions within the epitope of pre-F RSV protein, which is the target of nirsevimab, after the implementation of the mAb. We searched across PubMed, Scopus, Web of Science and ClinicalTrial.gov for studies involving children with confirmed RSV infection, that conducted genomic analysis. RESULTS: Seven studies (five observational and two randomized controlled trials) including 2156 RSV-positive samples (RSV-A: 1347, RSV-B: 809) were analyzed. RSV-A strains showed limited variability within antigenic site Ø, with K65R being the most common substitution and K209E being the only intermediate-resistance RSV-A substitution. RSV-B strains demonstrated substantially higher substitution frequencies, particularly involving I206M, Q209R, and S211N. Most identified substitutions appeared to represent naturally occurring polymorphisms and retained susceptibility to nirsevimab, while multiple RSV-B substitutions and combinations involving residues 64-68 and 204-208 demonstrated reduced susceptibility or high-level resistance. Resistance-associated variants were detected in 28 of 2156 (1.3%) RSV-positive samples and exclusively among nirsevimab breakthrough infections. In a sub-analysis restricted to nirsevimab-treated individuals, resistance-associated variants were significantly more frequent among RSV-B than RSV-A (9.8% vs 0.5%; p < 0.001). CONCLUSION: Most substitutions that were detected within the nirsevimab antigenic site reflect ongoing natural RSV evolution and do not significantly affect nirsevimab susceptibility. However, detection of resistance-associated variants highlights the importance of continuous genomic and phenotypic surveillance.

Humans↗

PubMed2026

Development and validation of a novel LC-MS/MS method for simultaneous quantification of fidaxomicin and metabolite (OP-1118) from feces for gut pharmacobiome studies.

Fidaxomicin is a first-line antibiotic for treating Clostridioides difficile infection. While it has low systemic absorption and reaches high colonic concentrations, it is hydrolyzed to a less active metabolite, OP-1118. Few studies have completely described critical experimental details of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quantifying fecal fidaxomicin and OP-1118. This study developed and validated a simple, fast, and sensitive LC-MS/MS method to quantify fidaxomicin and OP-1118 in human and mouse feces. This method simplified fecal sample preparation without the use of solid phase extraction and optimized LC-MS/MS parameters. A broad working range (0.3-1000 ng/ml) in both diluted human and murine fecal matrices was achieved with good intra- and inter-day accuracy (93-107%), precision (1-7%), and recovery (70-105%) as well as little IS-normalized matrix effects. This method was utilized to quantify fidaxomicin and OP-1118 in human and murine fecal samples. This novel method was simple, fast, sensitive, and accurate in analyzing fecal fidaxomicin and OP-1118 and could be deployed to facilitate gut pharmacobiome research.

Feces↗

PubMed2026

New World screwworm: a re-emerging parasitic threat.

PURPOSE OF REVIEW: New World screwworm (NWS) is an emerging parasitic threat in Central America and Mexico, which is spreading northward into the southern United States. Here we highlight the changing epidemiology, lifecycle of the NWS fly, clinical presentation, identification, treatment, and potential complications of NWS myiasis. RECENT FINDINGS: Despite decades of successfully containing NWS flies south of the Darien Gap in southern Panama, NWS flies reemerged in the Central America region in 2023 and have continued to spread northward ever since. On 3 June 2026, United States Department of Agriculture (USDA) confirmed the identification of an NWS infestation in a young calf in southern Texas. In addition to describing the current epidemiology of the NWS outbreak, we present information about clinical presentation and management of NWS myiasis in patients and include representative cases of patients who experienced NWS myiasis. SUMMARY: This review provides important epidemiologic and clinical updates to an emerging parasitic threat so clinicians can understand the risks and clinical management for patients with suspected NWS myiasis.

Animals↗

PubMed2026

Suppression of HIV-1 replication in CEM-A cell cultures by trans-splicing group I introns targeting PAS/PBS sequences and conditionally expressing ΔN-Bax.

Anti-HIV group I introns containing antisense guide sequences directed against the HIV-1 primer activation signal and primer-binding site (PAS/PBS) were designed and evaluated. Because PAS/PBS sequences are present in the viral RNA species examined, these RNAs can serve as trans-splicing substrates. The introns were active against both artificial target RNAs and viral RNA generated during infection. Cleavage and degradation of targeted viral RNA may have contributed to suppression, whereas inclusion of a 3' exon encoding the proapoptotic protein ΔN-Bax was associated with increased programmed cell death and may have augmented suppression of viral replication. In cultured CEM-A cells, transgene expression of these introns markedly suppressed HIV-1 replication, with p24 levels falling below the assay detection limit in selected clones. RESULTS: RT-PCR and sequence analysis detected splice products containing the expected PAS/PBS junctions. In the dual-luciferase assay, intron expression reduced normalized Gaussia luciferase signal by approximately 70% relative to the negative control. Qualitative Annexin V imaging and caspase-3 assays were consistent with infection-dependent apoptosis after ΔN-Bax splice-product formation. Transient expression of each intron in HEK293T cells followed by infection with VSV-G-pseudotyped HIV-1NL4-3 at an MOI of 2 reduced p24 levels by approximately 50% at 4 days post-infection. Construct 128L produced the strongest RT-PCR band under the tested conditions and was selected for subsequent experiments. A canonical splice product and a low-abundance noncanonical splice product were detected; both involved the intended HIV-derived target RNA, although transcriptome-wide off-target splicing was not assessed. Heterogeneous transformed HEK293T populations showed an approximately 2-log10 reduction in p24. In selected clonal HEK293T and CEM-A lines, p24 was below the assay detection limit at the measured endpoints, including up to 90 days after infection in some CEM-A clones. CONCLUSIONS: PAS/PBS-targeting group I introns suppressed HIV-1-associated p24 production in the tested cell-culture models. Linking the introns to a ΔN-Bax 3' exon was associated with infection-dependent apoptosis and may further limit viral replication and spread. The use of highly conserved, functionally constrained target sequences may reduce the likelihood of escape, but viral evolution and transcriptome-wide off-target effects were not assessed. This conditional death-upon-infection strategy warrants further evaluation in primary-cell and in vivo models.

Humans↗

PubMed2026

Culture of infectious human norovirus isolated from live contaminated oysters.

Human noroviruses are a major cause of foodborne outbreaks worldwide. Filter-feeding shellfish, such as oysters, can bioaccumulate these viruses in their digestive tissue when grown in sewage-impacted coastal areas and are often implicated in norovirus foodborne outbreaks. Despite the high sensitivity of current molecular assays, these methods for norovirus detection in shellfish fail to distinguish between infectious and non-infectious particles. Assessing norovirus infectivity in shellfish remains a challenge due to the lack of suitable isolation methods that maintain capsid integrity. In this study, a protocol for isolating infectious norovirus from oyster tissues, based on chloroform-butanol elution and polyethylene glycol concentration (CB-PEG), was optimized for the recovery of human norovirus GI and GII. While CB-PEG method recovered various norovirus GI and GII genotypes, it was less efficient at the genomic level than a protocol based on proteinase K elution (adapted from ISO 15216) and showed genotype-dependent viral recovery rates. By optimizing the flocculation step, we improved the method's compatibility with human intestinal enteroid (HIE) cultures. Using this approach, we successfully quantified infectious norovirus GII.3 titers recovered from artificially-contaminated live oysters. Interestingly, infectious virus was better isolated following a freezing step of the digestive tissues, with titers ranging from 13 to 40 TCID50/mL for positive samples. In conclusion, this study established an optimized methodological approach for the relative quantification of infectious norovirus GII.3 in shellfish, paving the way for future research on viral persistence and inactivation strategies in this foodstuff.

Norovirus↗

PubMed2026

Pre-transport dietary chitosan improves the physiological robustness of juvenile largemouth bass (Micropterus salmoides) by modulating antioxidant and inflammatory responses.

The acute stress caused by long-distance transport can lead to oxidative damage, immune dysfunction, and health deterioration in fish. This study evaluated dietary chitosan as a pre-transport nutritional strategy for juvenile largemouth bass (Micropterus salmoides). Five experimental diets contained chitosan at 0, 2.5, 5.0, 7.5, or 10.0 g/kg, designated as p0, p25, p50, p75, and p100, respectively, for 56 d. The effects of dietary chitosan were evaluated using growth performance, feed utilization, digestive function, antioxidant capacity, nonspecific immunity, and resistance to Aeromonas hydrophila infection. Then, fish from the p0 and p50 groups underwent a 12-h transport stress test, with samples collected before, during, and 7 d after transport. Dietary chitosan improved most of these parameters. Among the treatment groups, p50 and p75 showed the best overall performance. The dose-response analysis further indicated that the appropriate dietary inclusion range was 5.0-7.5 g/kg. Under transport stress, fish in the p50 group exhibited more stable antioxidant enzyme responses and lower lipid peroxidation, as indicated by reduced MDA levels. Consistent with these enzyme responses, antioxidant-related genes remained relatively stable. At the same time, expression patterns related to the Nrf2-Keap1 and NF-κB signaling pathways suggested that 5.0 g/kg chitosan alleviated transport-induced oxidative damage and inflammation. Dietary chitosan also attenuated pro-inflammatory gene induction and altered the temporal expression patterns of anti-inflammatory genes. Overall, 5.0-7.5 g/kg dietary chitosan is suitable for juvenile largemouth bass, and 5.0 g/kg may serve as an effective pre-transport dietary inclusion level.

Animals↗