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PubMed2026

A contextual activity score (CAS) for inferring ADAR-associated transcriptional activity across RNA-seq, single-cell, and spatial transcriptomics.

BACKGROUND AND OBJECTIVE: Adenosine-to-inosine RNA editing, catalyzed by Adenosine Deaminases Acting on RNA (ADARs), is a widespread modification involved in neural function, immune regulation, and cancer. The Alu Editing Index (AEI) is the standard metric to estimate ADAR activity but requires raw sequencing reads and is poorly suited for single-cell and spatial transcriptomic data. This study aimed to develop an alternative framework for inferring ADAR-associated transcriptional activity from gene expression data across diverse transcriptomic technologies. METHODS: We developed the Contextual Activity Score (CAS), a framework based on transcriptional signatures from ADAR perturbation experiments. Context-specific signatures were generated for human neurons, mouse neurons, and cancer models to infer ADAR1 and ADAR2 activity. CAS was computed from normalized gene expression matrices using regulon-based enrichment analysis. Performance was evaluated by comparing with the Alu Editing Index across bulk RNA sequencing datasets, simulated sequencing depths, and library preparation protocols. RESULTS: CAS showed strong concordance with the Alu Editing Index across multiple datasets, while remaining robust to reduced sequencing depth and different library protocols. Unlike the Alu Editing Index, CAS can be applied to single-cell and spatial transcriptomic data and enables the independent assessment of ADAR2 activity. In cancer and neuronal contexts, CAS captured biologically meaningful variations in ADAR-associated transcriptional activity at sample, cell-type, and spatial levels. CONCLUSION: CAS provides a scalable approach applicable across multiple RNA-seq protocols for estimating ADAR-associated transcriptional activity using gene expression data. This method, implemented in an open-source R package for broad adoption, expands the ability to study ADAR-associated transcriptional activity across transcriptomic modalities where direct editing quantification is challenging, such as single-cell and spatial transcriptomics.

Adenosine Deaminase↗

PubMed2026

Unraveling a Diagnostic Enigma: A TECPR2 Case Solved Through Multi-Omic Genomics.

TECPR2 is a key regulator of autophagy, encoded by the TECPR2 gene. Pathogenic variants in this gene have been linked to a rare hereditary sensory and autonomic neuropathy with intellectual disability (HSAN9). We report a teenage female with a syndromic intellectual disability disorder associated with neuromuscular abnormalities. Multi-omics analysis including genomics, transcriptomics, and proteomics, together with muscle biopsy from the affected individual, were used in this clinical case. Through trio exome sequencing we identified two heterozygous variants in the TECPR2 gene, NM_014844.4: c.480G>A; p.(Gln160=) and c.2846C>A; p.(Ala949Glu). Both were classified as variants of uncertain significance due to the lack of supporting evidence for pathogenicity. Subsequent long-read sequencing phased the variants and confirmed they were in trans. Additional functional studies using RNAseq and proteomics analyses verified the pathogenicity of the variants. This case study demonstrated the value of a multi-omics assisted analysis, which complemented the traditional phenotype-first approach in reaching a definitive clinical diagnosis.

Humans↗

PubMed2026

Portable metagenomics for preventive surveillance and outbreak control in livestock and poultry: Pathogen detection, resistome profiling, and antimicrobial stewardship.

Conventional diagnostics for livestock and poultry outbreaks commonly rely on culture or targeted PCR panels, which may be too slow or too narrow to guide early control decisions. Portable metagenomics, particularly real-time nanopore sequencing, offers a route to broad pathogen detection, antimicrobial-resistance gene profiling, and outbreak investigation within an integrated workflow. This implementation-focused review evaluates how near-point-of-care metagenomics may support preventive veterinary medicine through earlier detection, surveillance, cohorting, biosecurity decisions, and antimicrobial stewardship. We synthesize sample-to-answer workflows for enteric and respiratory disease in food-producing animals, including sampling, nucleic-acid extraction, host depletion or target enrichment, library preparation, sequencing, bioinformatics, quality control, and interpretation. Applications in calf diarrhea, bovine respiratory disease, poultry outbreaks, mastitis, and resistome monitoring are considered alongside the central limitation that detection alone does not establish causation. Pathogen and resistance-gene signals must therefore be interpreted with clinical signs, lesions, epidemiology, controls, and confirmatory testing. We also propose a minimum reporting checklist, intended as a practical framework rather than a validated consensus standard. Portable metagenomics is not a replacement for conventional diagnostics, but appropriately validated workflows can reduce uncertainty during time-sensitive outbreaks and support more judicious antimicrobial use.

Animals↗

PubMed2026

Ramu stunt virus genome reveals previously unreported segments and nucleocapsid domain duplication in Mechlorovirus.

Ramu stunt virus (RmSV), a member of the genus Mechlorovirus within the family Phenuiviridae, was previously described as a six-segmented RNA virus infecting sugarcane. In this study, we re-examined type material and additional isolates using high-throughput sequencing and RT-PCR validation, revealing that RmSV possesses a nine-segmented genome, making it the largest reported in the Phenuiviridae. This expanded architecture includes duplicated RNA segments (RNA 2a and RNA 2b) encoding nucleocapsid-like proteins and two novel segments (RNA 7 and RNA 8). Comparative analysis showed that RNA 2a and 2b share about 84% amino acid identity, while RNA 5 encodes a third nucleocapsid homolog, indicating unprecedented domain redundancy. Structural modeling confirmed that all three nucleocapsid proteins maintain a conserved fold despite low sequence identity, with electrostatic mapping suggesting differential RNA-binding potential. Additionally, RNA 6 encodes a hypothetical protein structurally similar to the rice stripe virus disease-specific S-protein, implicating a role in symptom development. Transcript abundance analysis revealed RNA 6 as the most highly expressed segment across isolates. These findings revise the genomic composition of RmSV, highlight mechanisms of genome plasticity and adaptive evolution in plant-infecting bunyaviruses, and underscore practical implications for diagnostic assay design, resistance breeding, and biosecurity surveillance.

Genome, Viral↗

PubMed2026

Advanced/Novel Stenting for Pediatric Dynamic Airway Collapse.

Pediatric dynamic airway collapse is a complex condition that can impact all levels of the pediatric airway. These conditions can pose life threatening risk to pediatric patients and carry lasting impacts. While traditionally, tracheostomy has been used to address all levels of dynamic collapse, recent advances have allowed for more individualized, anatomy-specific stenting and splinting strategies for treatment. This article covers pathophysiology and the latest evidence on strategies to address nasopharyngeal, oropharyngeal, proximal trachea, and tracheobronchial dynamic collapse.

Humans↗

PubMed2026

[Analysis of a Chinese pedigree affected with Townes-Brocks syndrome due to a novel variant of SALL1 gene and a literature review].

OBJECTIVE: To analyze a novel exonic variant of the SALL1 gene and its impact on the binding site of SALL protein. METHODS: Clinical data of three children diagnosed with Townes-Brocks syndrome and their family members who had presented at the First Affiliated Hospital of Shandong First Medical University in April 2022 were retrospectively collected. The pathogenic variant was identified through whole-genome sequencing (WGS) and validated by Sanger sequencing. Protein structural prediction was performed using AlphaFold and PyMOL software to construct three-dimensional models of the wild-type and mutant proteins. Additionally, previously reported cases were systematically reviewed. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2023-386). RESULTS: The proband was one of triplet sisters born at 34+4 gestational weeks. All three cases had presented with anal atresia and rectovaginal fistula, and case 3 also had toe malformation of left foot. WGS revealed a novel heterozygous c.757C>T (p.Gln253*) variant in the SALL1 gene, which was predicted to be pathogenic. Sanger sequencing confirmed co-segregation of the variant with the disease within the family. Protein structural modeling demonstrated that the variant has introduced a premature stop codon at position 253, resulting in a truncated protein. CONCLUSION: Above finding has enriched the mutation spectrum of the SALL1 gene in association with Townes-Brocks syndrome, which also represented a rare case of anal atresia in triplets, and provided a basis for molecular diagnosis, genetic counseling, and further research.

Humans↗

PubMed2026

Effects of anodal transcranial direct current stimulation over the right primary motor cortex on a sequential motor finger tapping task in developmental stuttering.

INTRODUCTION: This study investigates the impact of anodal transcranial direct current stimulation (tDCS) on non-speech sequential motor practice in adults who stutter (AWS), compared to non-stuttering controls (ANS). Recent research has explored the effects of tDCS on speech fluency in stuttering. However, its effect on non-speech motor tasks has not yet been studied. METHODS: 20 AWS and 30 ANS right-handed participants were randomly assigned to anodal or sham tDCS conditions, performing a sequential finger tapping task. We targeted over the right primary motor cortex, stimulating at 2 mA for 20 min. Sequence duration and reaction time were analyzed. RESULTS: AWS analysis revealed that the anodal condition had significantly slower reaction times in the second half of the task compared to sham. For sequence durations, AWS in the anodal condition had slower overall sequence durations than the sham condition. However, there were no block-by-block differences in sequence duration. When comparing AWS and ANS, no significant differences were observed for sequence duration. However, there were significant differences in reaction time between AWS and ANS, specifically in earlier blocks. Additionally, there was no significant Group × Condition interaction. DISCUSSION: The findings suggest that anodal stimulation impeded finger sequencing in AWS, showing overall slower sequence durations and a diminishing effect on reaction times in the second half of the experiment, suggesting anodal tDCS may interact uniquely with the neural mechanisms in stuttering. Future studies should explore the effects of anodal tDCS on non-speech motor tasks to gain a broader understanding of its impact on motor control and motor learning.

Humans↗

PubMed2026

Regional genomic analysis of lineage distribution and transferable multidrug resistance among chicken-associated Salmonella Kentucky isolates in China.

Salmonella enterica serovar Kentucky is an important multidrug-resistant foodborne pathogen in the poultry meat supply chain. Although recent broader genomic studies have elucidated the population structure and epidemiological significance of major lineages in China (e.g., ST198 and ST314), the regional dynamics within local poultry supply chains remain insufficiently characterized. In this study, 31 chicken meat-derived isolates from Shanghai and 39 publicly available genomes from China were analyzed using antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, conjugation experiments, and complete sequencing of representative plasmids. This enabled a systematic characterization of the molecular epidemiological features of the population and the mechanisms underlying resistance dissemination. Population genomic analysis revealed a lineage composition markedly different from the global epidemiological pattern: ST314 was the predominant sequence type among the Shanghai chicken-derived isolates (74.2%), whereas the internationally recognized high-risk clone ST198 accounted for only 25.8% of the local isolates. However, risk stratification analysis indicated that although ST198 was detected less frequently, it carried a significantly greater burden of acquired resistance genes and therefore represented a higher-risk resistant lineage. Functional and structural validation further elucidated the molecular basis of resistance dissemination within this high-risk lineage. Conjugation experiments confirmed the co-transfer of a multidrug resistance module carrying blaTEM-1 and blaCTX-M-267 to the recipient strain Escherichia coli J53. Complete plasmid analysis revealed that these two β-lactam resistance genes were co-localized on a 242-kb transferable plasmid flanked by Tn1331, Tn3, and multiple transposase-associated elements, thereby providing a structural basis for their horizontal transfer. This study provides important molecular epidemiological evidence for lineage-specific surveillance and risk-stratified control of resistant Salmonella in the poultry meat supply chain and further underscores the need for continuous monitoring of mobile genetic elements within a One Health framework.

Animals↗

PubMed2026

Genomic and food-safety evaluation of Staphylococcus chromogenes in Chinese dairy milk.

Non-aureus staphylococci and mammaliicocci (NASM) cause mastitis and may contaminate milk and dairy products. Milk samples (n = 1916) from cows with subclinical or clinical mastitis (SCM and CM, respectively) were collected from 28 large-scale (> 500 lactating cows) Chinese dairy farms. Overall, 999 NASM isolates representing 19 species were identified by MALDI-TOF MS and cpn60 sequencing, with Staphylococcuschromogenes, Mammaliicoccus sciuri and Staphylococcus haemolyticus being most prevalent. Antimicrobial resistance (AMR) was determined with disc diffusion; non-susceptible to penicillin was most common (SCM, 30% and CM, 29%) whereas cefoxitin non-susceptible NASM accounted for 8-10% of isolates; among these, 12.5% carried mecA but none carried mecC. Galleria mellonella was used to assess virulence of 78 strains of S. chromogenes, a dominant species; subsequently, 32 strains, representing higher- and lower-virulence in the Galleria model, were selected for whole-genome sequencing and comparative genomics. S. chromogenes isolates from CM had higher virulence (p < 0.05) than those from SCM. The 32 genomes comprised 20 sequence types, indicating high genetic diversity. No robust genomic marker of Galleria virulence phenotype was identified in this selected WGS subset. Acquired resistance genes (n = 5) were detected, including a first report of fusC in S. chromogenes; the fusC-positive isolate had an elevated fusidic acid MIC (8 mg/L). Although S. chromogenes persisted in milk at 4 °C, pasteurization (64 °C for 30 min) reduced viable counts to below detection. This study provided new insights into the prevalence, AMR, genomic diversity, and dairy-chain relevance of milk-derived NASM, particularly S. chromogenes. However, the genomic findings were based on an intentionally selected WGS subset and should be interpreted as hypothesis-generating rather than population-representative.

Animals↗

PubMed2026

Phylogenomics and female reproductive morphology reframe the classification of the Halymeniales (Rhodophyta).

The red algal order Halymeniales (Rhodophyta) exhibits remarkable morphological and taxonomic diversity but its higher-level relationships remain poorly resolved. Here, we present a comprehensive phylogenomic analysis based on newly generated plastid (170 protein-coding genes), mitochondrial (23 genes), and complete nuclear ribosomal cistron sequences from 56 taxa, complemented with an expanded rbcL dataset encompassing 334 sequences. Our results provide a robust phylogenomic framework for the Halymeniales, offering a taxonomic backbone for future systematic studies. The analyses consistently recover six early-diverging lineages (Acrodiscus, Isabbottia, Norrissia, Pachymenia, Zymurgia, and Tsengia) and two strongly supported larger clades (Halymenia s.l. and Grateloupia s.l.). While most small and recently described genera are monophyletic, several traditional genera (e.g., Halymenia, Cryptonemia, Grateloupia) are poly- or paraphyletic, requiring considerable taxonomic revision. At the family level, the data indicate that reinstatement of the Grateloupiaceae sensu Kim et al. (2021) would entail a revised circumscription of the Halymeniaceae and the recognition of at least five small families to accommodate the early-diverging lineages. Although such a revised classification would result in monophyletic families, it is not supported by morpho-anatomical characters. Instead, we propose a more stable two-family system, recognizing a broadly circumscribed Halymeniaceae that is sister to the Tsengiaceae. Female reproductive characters, particularly the structure of carpogonial and auxiliary cell ampullae, support this two-family system and further characterize many genus-level clades, although substantial convergence across lineages exists.

Phylogeny↗

PubMed2026

Genome-wide insights into the evolutionary and demographic history of the red alga Mazzaella laminarioides: Evidence for speciation with ancient migration along the southeast Pacific coast.

The mechanisms driving lineage divergence in red algae remain unexplored, despite the group's remarkable diversity and ancient evolutionary history. The red alga Mazzaella laminarioides, a Chilean intertidal species complex composed of three parapatric cryptic lineages (North, Center, South), offers a valuable system to evaluate these processes, as its life history combines severe dispersal limitation with a haploid-diploid cycle that may influence the emergence of reproductive barriers. We reconstructed its evolutionary history using whole-genome sequencing and nuclear genome assembly of representative individuals from each lineage. Phylogenomic analyses based on 1,507 single-copy orthologs recovered three deeply divergent lineages with limited nuclear discordance consistent with incomplete lineage sorting. For both splits, demographic modelling was most consistent with an Ancient Migration scenario, although support over strict isolation was moderate, suggesting that divergence may have begun with low asymmetric ancestral gene flow followed by subsequent loss of connectivity, demographic bottlenecks, and later population expansion. Coding sequence analyses revealed lineage-specific dN/dS heterogeneity; only one South-lineage locus passed FDR correction (metaxin-1, mitochondrial protein import), with two further South-lineage candidates in chlorophyll and heme biosynthesis falling below the FDR threshold. Together, these signals suggest that divergent selective pressures on energy acquisition may have contributed to divergence at the southern end of the distribution. These results add to the small but growing body of whole-genome data for red algae and, alongside recent macroalgal studies, suggest that ancestral connectivity could be a recurrent feature of lineage divergence even in marine organisms with extremely restricted dispersal.

Rhodophyta↗

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

Lower-limb electromyographic responses across four recumbent cycling configurations in healthy young men.

Recumbent cycling provides an adjustable configuration in which backrest angle and crank-axis height can alter lower-limb loading. Backrest angle changes the orientation of the active musculature relative to gravity, whereas crank-axis height modifies the foot-pedal interface and the ankle lever arm. Whether such positioning is associated with differences in lower-limb electromyographic (EMG) activation across both factors together has not been examined. Using a randomized crossover design, fifty-nine healthy young men cycled at 100 W and 50 rpm under four conditions combining two backrest angles (30°, 75°) and two crank-axis heights (Rh, high, 77 cm; Rl, low, 45 cm). Surface EMG from the rectus femoris (RF), biceps femoris (BF), and gastrocnemius medialis (GAS) was analyzed for root mean square (RMS) amplitude, absolute onset sequence, and relative recruitment timing (%Sequence, derived using Telescan software and referenced to RF). RMS amplitude did not differ across conditions for any muscle (all p ≥ 0.356), and absolute onset sequence showed no condition effect (all p ≥ 0.197). For GAS %Sequence, the Greenhouse-Geisser-corrected omnibus test was significant (F(1.32, 76.56) = 28.45, p < 0.001), driven by a within-30° contrast in which %Sequence was lower under Rl than Rh (paired t(58) = 10.39, Holm-adjusted p < 0.0001; mean difference 22.0 percentage points, 95 % CI [17.8, 26.3]; dz = 1.35). Because %Sequence is referenced to RF, this exploratory shift should be interpreted cautiously. Lower-limb activation may be constrained by the closed-chain nature of pedaling, whereas distal recruitment timing may be sensitive to crank-axis height and the foot-pedal interface.

Humans↗

PubMed2026

Complex evolutionary history of Rosales mediated by extensive incomplete lineage sorting and hybridization.

The angiosperm order Rosales still represents a major challenge for phylogenetic reconstruction. Although its circumscription is now well-defined, phylogenetic relationships among families are still uncertain. Here, we used nuclear, plastid, and mitochondrial genomic data from 33 species representing all nine families to further clarify interfamilial relationships and the group's evolutionary history. We detected significant phylogenetic conflict among the three datasets. Further analyses at the nuclear level identified incomplete lineage sorting (ILS) as the main cause of unstable phylogenetic positions among families. The discordant placements of Rhamnaceae and Elaeagnaceae based on plastid and mitochondrial data are caused by ancient hybridization events, potentially involving differences in organellar inheritance. Our molecular dating confirms earlier suggestions that the ancient rapid diversification of the three Rosaceae subfamilies could be the main reason for the difficulties in resolving their phylogenetic relationships. Our findings provide new insights into the interfamilial relationships of Rosales and demonstrate that the evolutionary history of this order was shaped by ancient and rapid radiation as well as extensive ILS and reticulate evolution. They also suggest that previous attempts to clarify interfamilial relationships in this order were hampered by combining nuclear and organellar sequence data, leading to inconsistent topologies observed across earlier studies.

Phylogeny↗

PubMed2026

Novel splice site variants in GBA1 are associated with Gaucher disease and genotype-phenotype correlations.

BACKGROUND: Variants in GBA1 are associated with neurodegenerative disease. This study aimed to explore pathogenic GBA1 variants. METHODS: Four patients with progressive myoclonic epilepsy (PME) and extremely low β-glucosidase levels were recruited. Whole-exome sequencing and long-range PCR were performed to identify GBA1 variants. Bioinformatic analyses were used to predict the impact of the identified variants. A literature review was performed to explore the genotype-phenotype correlations. GBA1 expression data across different brain regions and developmental stages were analyzed using the BrainSpan database. RT-PCR was performed to verify the splicing effects. RESULTS: Compound heterozygous GBA1 variants were identified in four patients. Five distinct variants were detected, including two novel splice site variants (c.308-2A>G and c.762-2A>C) and three previously reported variants. All identified variants were rare or absent in gnomAD. Splice site variants c.308-2A>G and c.762-2A>C were predicted to cause aberrant splicing. Minigene-based splicing assays coupled with RT-PCR and Sanger sequencing confirmed that both variants cause complete exon skipping (exon 4 and exon 7, respectively). All patients presented with PME onset in childhood/adolescence, intellectual regression, low β-glucosidase, and diffuse brain atrophy and were subsequently diagnosed with Gaucher disease type 3. GBA1 expression in the brain showed two distinct peaks: one in infancy and another after five years of age. The onset age of PME aligned with the second GBA1 expression peak (after five years of age). CONCLUSION: This study identified compound heterozygous GBA1 variants, including two novel candidate pathogenic splice site variants, in Gaucher disease type 3 patients, expanding the known mutational spectrum.

Humans↗

PubMed2026

Exercise-associated epigenetic remodeling and TCR repertoire dynamics in Lynch syndrome carriers.

Lynch syndrome (LS) carriers are at elevated cancer risk. Emerging evidence suggests that exercise may serve as a non-pharmacologic preventive strategy, yet the epigenetic and immunological mechanisms underlying its protective effects in this population remain unclear. Here, we perform integrative multi-omics profiling of DNA methylation, gene expression, and the T cell receptor (TCR) repertoire in LS carriers undergoing a 52-week aerobic cycling intervention. We identify compartment-specific DNA methylation changes, including innate immune activation in cfDNA and oncogenic pathway repression in tissue. Integrative transcriptomic analysis highlights ISL1 as a key exercise-repressed, epigenetically regulated gene, and identifies FLCN as a colorectal cancer (CRC)-associated methylation target. TCR analysis reveals an exercise-associated increase in systemic repertoire diversity and tissue-specific clonal convergence, thus suggesting antigen-driven recruitment. Collectively, these findings uncover epigenetic and immune remodeling as potential mechanisms of exercise-mediated protection in LS.

Lynch syndrome↗

PubMed2026

Comparative analysis of gut microbiota in yaks under different feeding management strategies during cold seasons.

Yaks (Bos grunniens) are crucial for the livelihoods of pastoral communities in cold regions, where feed scarcity during the cold season poses challenges to their health and productivity, underscoring the necessity of understanding how dietary management influences the gut microbiota. In this study, 24 yak steers matched for body weight and health status were randomly allocated to four groups: natural grazing or indoor feeding with roughage-to-concentrate ratios of 50:50, 70:30, or 90:10. Fecal samples were collected for 16S rDNA sequencing and subsequent functional prediction of the microbiota. The results showed that Firmicutes and Bacteroidetes were the dominant phyla across all groups, and UCG-005 and Rikenellaceae_RC9_gut_group were the predominant genera. Concentrate supplementation during the cold season significantly enhanced microbial richness and diversity, with the 70:30 ratio exerting the most pronounced beneficial effects on microbiota structure and key taxa enrichment. These findings highlight the critical role of dietary management in shaping the yak gut microbiota during cold seasons and suggest that the 70:30 ratio optimally improves microbial community structure, thereby promoting yak health and productivity under harsh climatic conditions. Future research should explore the long-term implications of such dietary strategies.

Animals↗

PubMed2026

Tigecycline-resistant Staphylococcus in waiting pens of a pig slaughterhouse: genomic insights into a food safety alert.

BACKGROUND: The waiting pens of slaughterhouses represent a critical control point in the 'farm-to-fork' continuum, yet their role in the emergence and dissemination of antimicrobial resistance remains understudied. This study investigated tigecycline-resistant Staphylococcus (TRS) in these high-risk zones to assess their prevalence, resistance mechanisms, and transmission dynamics. METHODS: 400 samples were collected from the waiting pens of a pig slaughterhouse in Guangzhou, China. Antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, and molecular cloning were employed to characterize resistance mechanisms and transmission patterns. RESULTS: 78 TRS strains were isolated and classified into three species, including S. borealis, S. ureilyticus, and S. pasteuri. These isolates exhibited multidrug-resistant phenotypes and carried new mutations in rpsJ and tet(M), which were functionally confirmed to reduce tigecycline susceptibility. Phylogenetic evidence demonstrated clonal transmission between pig farms and the slaughterhouse. The tet(M) gene was located within Staphylococcal cassette chromosome mec elements mediated by IS257, while tet(L) was carried by plasmids formed through IS256/IS257-mediated recombination. CONCLUSIONS: Waiting pens serve as crucial reservoirs for the amplification and dissemination of antimicrobial resistance. Our findings underscore the urgent need for enhanced biosecurity measures, improved waste management, and routine molecular surveillance in these high-risk zones to mitigate the spread of resistance along the food production chain.

Animals↗