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Safe and Stable Germline Transmission of MSTN Mutations in Cattle.

With the global population expected to reach 10 billion by 2050, sustainable livestock production is critical. Gene editing of the myostatin (MSTN) gene represents a promising strategy to enhance muscle growth in cattle. In this study, MSTN-mutated founder (F0) cows were used to generate F1 offspring via ovum pick-up, in vitro fertilization, and embryo transfer. Four F1 calves were born, all confirmed to be heterozygous for the MSTN mutation. Long-term monitoring showed normal growth and no visible health abnormalities. Whole-genome sequencing identified SNPs, INDELs, and structural variants, most with minimal predicted functional effects. Proteomic profiling of Longissimus dorsi muscle quantified 2947 proteins, revealing only subtle expression differences between MSTN-mutated and wild-type cattle. These results demonstrate stable inheritance and confirm that MSTN editing does not disrupt genome integrity or protein expression. Overall, our findings support the safety and utility of MSTN gene editing to improve livestock productivity for future food security.

Animals

Assessing the Frequency of VEXAS-Related Canonical UBA1 Mutations in Myelodysplastic Syndrome Patients.

OBJECTIVES: Somatic mutations in the UBA1 gene cause VEXAS syndrome, which presents with inflammatory and hematological symptoms. Case studies show a strong overlap between VEXAS and myelodysplastic syndrome (MDS). Recognizing VEXAS is important for differential diagnosis in patients with both inflammation and MDS, as accurate identification guides treatment. The study focuses on determining how often canonical UBA1 mutations linked to VEXAS occur in MDS patients. METHODS: Patients diagnosed with MDS were enrolled in the study, and genomic DNA was isolated from bone marrow FFPE samples. Molecular analysis was performed using a specifically designed ARMS-PCR approach. Additionally, protein-protein interaction (PPI) studies combined with bioinformatic analyses were carried out to explore potential links between UBA1 and pyroptosis. RESULTS: Among the 149 MDS patients analyzed, none exhibited high-Variant Allele Frequency (VAF) the canonical UBA1 point mutations linked to VEXAS syndrome. PPI analysis revealed a possible association between UBA1 and the NLRP3 inflammasome component. CONCLUSIONS: Expanding the sample size and using targeted NGS or ddPCR would improve mutation detection sensitivity and could reveal UBA1 canonical and non-canonical variants and more accurately estimate the frequency of VEXAS-related mutations in the MDS population.

Humans

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

Histopathologic, Genomic, and Clinical Characteristics of Primary Cutaneous Melanocytic Tumors With Concomitant NRAS Q61 and IDH1 R132C Mutations.

Cutaneous melanocytic tumors with concomitant NRAS Q61 and IDH1 R132C mutations have been described as intermediate-grade melanocytomas with characteristic biphasic morphology, but the malignant end of this genotype-defined spectrum remains poorly characterized. We assessed histopathologic, immunohistochemical, molecular, and clinical features of 16 primary cutaneous melanocytic tumors harboring both mutations. Following integrated review, 7 tumors were classified as melanocytoma and 9 as melanoma. Melanocytomas showed reproducible biphasic architecture with congenital nevus-like features, a biphasic HMB-45 pattern, low Ki-67, PRAME negativity, retained p16, and minimal copy number variations (CNVs). Melanomas retained partial morphologic overlap in a subset but were distinguished by higher-grade cytology, immunohistochemical features supportive of malignancy, and progression-associated genomic alterations, including TERT promoter mutation (9/9), 9p21/CDKN2A loss (4/7), and higher CNV burden. NRAS and IDH1 variant allele frequencies were strongly concordant (r = 0.83, P < 0.001), supporting their presence in the same dominant clone. Clinically, two patients presented with stage IIIB disease, but no distant metastasis or melanoma-related death occurred during a median melanoma follow-up of 3.9 years (IQR, 2.5-5.1). In exploratory analyses, moderate-to-severe atypia (RR, 6.2; 95% CI, 1.0-38.8; P = .009), Ki-67 &#x2265;10% (RR, 4.4; 95% CI, 1.1-18.4; P = .003), lymphocytic infiltrate (RR, 2.4; 95% CI, 1.1-5.3; P = .03), absence of the typical biphasic pattern (RR, 2.4; 95% CI, 1.1-5.3; P = .03), and complete p16 loss (RR, 2.4; 95% CI, 1.1-5.3; P = .03) were associated with molecular or clinical progression to melanoma, defined as the presence of at least one of the following: TERT promoter mutation, pathogenic CDKN2A mutation, 9p21/CDKN2A loss, &#x2265;3 genome-wide segmental CNVs, or any metastasis. These findings support the existence of NRAS/IDH1 co-mutated melanoma as the malignant counterpart of NRAS/IDH1-mutated melanocytoma within a single genotype-defined spectrum.

IDH1 mutations

Seventeen-year follow-up of hypophosphatasia diagnosed in middle-aged siblings harboring a novel intronic and a rare missense ALPL gene mutation.

Hypophosphatasia (HPP) is the rare inborn-error-of-metabolism that features impaired mineralization of the skeleton and teeth due to a deactivating mutation or mutations of the gene ALPL which encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). We report 17-year follow-up of twin sisters and a brother referred in middle-age for painful proximal femoral "stress fractures" and then diagnosed with HPP. They reported generalized muscle and bone pain, metatarsal fractures, arthropathy and, since childhood, tooth loss. Their concordant findings were explained by compound heterozygosity in ALPL for a rare maternal missense mutation (c.1403C&#xa0;>&#xa0;T, p.Ala468Val) in exon 12, together with a novel presumably paternal change (c.863-14G&#xa0;>&#xa0;A) predicting a cryptic mRNA splice site in intron 8. Fractures continued during follow-up until one sister received a three-and-one-half-year course of hydroxyapatite-targeted TNSALP supplementation therapy (asfotase alfa) during which substantial improvement occurred in her clinical, biochemical, and functional parameters as well as quality of life. Following subsequent unplanned treatment cessation she suffered significant clinical deterioration, including new fractures and loss of mobility. Her bone histopathology documented osteomalacia. Treatment resumption restored its benefits. Among ten asymptomatic family members evaluated in this four-generation kindred, eight were carriers heterozygous for either ALPL mutation. Those harboring the maternal missense defect manifested mild hypophosphatasemia, suggesting a dominant-negative mutation effect. This experience underscores the importance of in-depth phenotyping and then clinical follow-up to characterize ALPL variant combinations, and for maintaining effective asfotase alfa treatment.

Humans

Frequent mutations in the BIRC3 gene promote metastatic potential of nasopharyngeal carcinoma cells through the TRAF2-NF-&#x3ba;B pathway.

Nasopharyngeal carcinoma (NPC) is a head and neck cancer characterized by highly locoregionally invasive behavior attributable to the latent infection with Epstein-Barr virus (EBV) and genomic instability. It is well established that EBV-encoded oncogenic molecules actively contribute to the malignant behavior of NPC cells. However, the mechanism by which aberrant genomic alterations enable NPC cells to become aggressive remains largely unknown. In the present study, whole-exome sequencing (WES) revealed that the gene encoding the baculoviral IAP repeat-containing 3 (BIRC3) protein was frequently mutated in circulating tumor cells (CTCs) but not in paired primary tumor cells from patients with metastatic NPC. A minigene assay indicated that the c.637&#xa0;A&#xa0;>&#xa0;G mutation disrupted normal mRNA splicing, resulting in the partial deletion of Exons 2 and 3 and altered stability of BIRC3 mRNA. In vitro experiments demonstrated that ectopic expression of the BIRC3c.637A>G mutant enhanced NPC cell invasive properties, including proliferation, resistance to apoptosis, migration, and invasion. Furthermore, overexpression of wild-type BIRC3 promoted invasive characteristics in NPC cells through the TRAF2-NF-&#x3ba;B signaling axis. In summary, BIRC3 acts as a regulator of the malignant features of NPC cells. Frequent BIRC3 mutations in CTCs, such as the c.637&#xa0;A&#xa0;>&#xa0;G mutation, further enhance the metastatic potential of disseminated NPC cells by inducing aberrant alternative splicing. These findings suggest the therapeutic feasibility of targeting the BIRC3/TRAF2/NF-&#x3ba;B axis in the treatment of NPC.

Humans

Molecular Landscape and Advanced Diagnostic Technologies for BRAF Mutations in Cancer: From Quantitative PCR and ddPCR to CRISPR-Based Platforms.

BRAF mutations are key oncogenic alterations across multiple malignancies, including melanoma, thyroid carcinoma, colorectal cancer, non-small cell lung cancer, glioma, and hairy cell leukemia. The most prevalent variant, BRAF-V600E, induces constitutive activation of the MAPK signaling pathway, promoting tumor progression and influencing therapeutic responsiveness. Accurate detection of BRAF alterations is therefore essential for molecular classification, prognostic assessment, treatment selection, and resistance surveillance. This review summarizes the molecular heterogeneity of BRAF mutations and critically evaluates current diagnostic methodologies. Conventional approaches such as allele-specific PCR and Sanger sequencing are compared with advanced quantitative platforms, including high-resolution melting analysis, droplet digital PCR, and next-generation sequencing, with emphasis on analytical sensitivity, mutation coverage, and clinical applicability. Emerging technologies such as CRISPR-based assays, rolling circle amplification systems, and nanoparticle-based biosensors and point-of-care diagnostic platforms are also discussed for their potential to enhance ultra-sensitive detection, particularly in liquid biopsy settings. These emerging tools are highlighted for their potential to enable ultra-sensitive, rapid, and decentralized mutation detection, particularly in liquid biopsy settings. Key challenges, including intratumoral heterogeneity, low allele-frequency variants, FFPE-associated artifacts, and clonal evolution under therapeutic pressure, are examined within a translational framework. In addition, we examine critical barriers to clinical implementation, including standardization, cost, and global accessibility of molecular diagnostics, and outline potential solutions through scalable technologies and decentralized testing strategies. We propose that optimal BRAF testing requires a mutation subclass-informed and clinically integrated strategy combining comprehensive baseline profiling with longitudinal molecular monitoring. Future diagnostic paradigms will likely integrate multi-omics data and artificial intelligence (AI)-assisted interpretation to refine precision oncology implementation. Looking forward, we propose that optimal BRAF testing will require integration of multi-omics profiling with AI-assisted interpretation, enabling automated variant classification, real-time clinical decision support, and improved prediction of therapeutic response and resistance.

Humans

Discrimination, chronic stress, and multimorbidity in cohort of Black and Latina transgender women with HIV: Longitudinal findings from the LITE Plus study.

Black and Latina transgender women with HIV (BLTWH) are exposed to repeated, intersecting discrimination based on race, gender, and serostatus. Minority stress theory conceptualizes discrimination as minority-specific stressors that drive health inequities. Allostatic load theory posits a pathway between discrimination and chronic disease through multisystem physiological dysregulation caused by chronic stress. To test this pathway, a longitudinal cohort of 108 BLTWH, enrolled December 2020 - June 2022 in Boston, New York City, and Washington, DC, were followed for 24 months, with biomarkers measured at baseline, 12, and 24 months. Questionnaires administered every 6 months assessed anticipated discrimination, everyday discrimination, perceived stress, and other psychosocial factors. Multimorbidity was measured via self-reported non-HIV chronic conditions. In mixed-effects mediation models, allostatic load did not mediate relationships between multimorbidity outcomes and anticipated discrimination (&#x3b2;: -0.0004 [95% CI: -0.004, 0.003]) nor everyday discrimination (&#x3b2;: -0.002 [95%CI: -0.009, 0.003]). Perceived stress demonstrated indirect effects on multimorbidity in unadjusted models of anticipated discrimination (&#x3b2;: 0.024, [95% CI: 0.015, 0.081]) and everyday discrimination (&#x3b2;: 0.021 [95%CI: 0.016, 0.077]). Indirect effects remained significant, with attenuated effects (&#x3b2;: 0.020 for anticipated discrimination; &#x3b2;: 0.017 for everyday discrimination) after adjusting for social support, community connection, and resilient coping. Total effects were only significant for the adjusted model of everyday discrimination (&#x3b2;: 0.056 [0.014, 0.099]). Findings suggest discrimination impacted health through specific psychosocial pathways. Alongside efforts to eliminate intersectional discrimination, stress-lowering interventions and increased access to social support and community connection may be effective approaches to reducing multimorbidity in this highly marginalized group.

Humans

Effects of Progressive Inspiratory Muscle Training on Lung Volume and Respiratory Strength in Patients With Pre-Dialysis Chronic Kidney Disease.

INTRODUCTION: Chronic kidney disease can present changes in thoracic cavity volume and respiratory muscle weakness, even in the pre-dialysis stage. However, there is little evidence on the effects of inspiratory muscle training in these patients. METHODS: This was a randomized clinical trial which comprised patients with Chronic Kidney Disease in stages 3, 4, and 5 undergoing conservative treatment, allocated experimental group (EG) with progressive loading (up to 50% of maximal inspiratory pressure [MIP]) and control group (CG) with a fixed load (5 cmH2O) and no load progression performed daily for 8&#xa0;weeks. The outcomes assessed were thoracic cavity volumes, as measured by optoelectronic plethysmography, and inspiratory and expiratory respiratory muscle strength. RESULTS: A total of 30 patients completed the study. All volumes significantly increased at the end of the protocol with a large effect size, but only the pulmonary thoracic cavity volume showed a significant interaction (F&#xa0;=&#xa0;3.698; p&#xa0;=&#xa0;0.042). There was an increase in inspiratory muscle strength in the EG (73.88-90.35&#xa0;cmH2O; p&#xa0;<&#xa0;0.001) and in the CG (70.85-86.92&#xa0;cmH2O; p&#xa0;=&#xa0;0.001), as well as in expiratory muscle strength in the EG (97.71-108.53&#xa0;cmH2O; p&#xa0;=&#xa0;0.001) and in the CG (80.69-94.77&#xa0;cmH2O; p&#xa0;=&#xa0;0.004). CONCLUSION: Daily IMT increased thoracoabdominal volumes, particularly pulmonary rib cage volume in the progressive-load group, as well as respiratory muscle strength in patients with pre-dialysis CKD. However, progressive-load IMT was not superior to minimal-load training.

Humans

Temporal shifts in gyrA mutation types and sublineage replacement in ST11 Salmonella enterica&#xa0;serovar Enteritidis over a decade (2014-2023): A genomic epidemiological study in Guangxi, China.

The overuse or abuse of antibiotics drives the global health threat of antimicrobial resistance. Although bans on certain veterinary antibiotics, such as colistin, have proven effective, the impact of fluoroquinolone stewardship on the evolution of the foodborne pathogen Salmonella enterica serovar Enteritidis (S. Enteritidis) remains unclear. Here, we conducted a decade-long (2014-2023) retrospective longitudinal genomic epidemiological analysis of 441&#xa0;ST11 S. Enteritidis isolates from Guangxi, China, alongside a global reference dataset of 4297 genomes. Our aim was to elucidate the effect of real-world antibiotic stewardship on the shift of gyrA point mutations and lineage distribution. Surveillance identified three global epidemic clade sublineages (GEC-L2, L3, L4), with the multidrug-resistant GEC-L4 (i.e., GC-c or MMC2), characterized by the gyrA mutation with amino acid substitution D87Y, being domestically dominant (70.07%, 309/441). Following China's 2016 ban on the veterinary use of critical fluoroquinolones, the proportion of the highly resistant GEC-L4 sublineage decreased continuously (from 86.84% in 2017 to 56.00% in 2023), while the less resistant GEC-L3 sublineage (i.e., GC-b or MMC1), mainly characterized by gyrA D87G, increased simultaneously (from 13.16% to 44.00%). This phenomenon might be attributed to the fact that the GEC-L4 sublineage exhibited a higher fitness cost compared with the GEC-L3 sublineage, as confirmed by the competition assay. A Random Forest Model validated that the gyrA mutation with amino acid substitution&#xa0;D87Y was the paramount feature for these sublineages' identification. In contrast, global data showed a continuous increase in gyrA mutations (from 8.63% in 2006 to 68.85% in 2024), primarily D87Y (from 1.44% to 31.15%) and D87N (from 4.32% to 22.95%), correlating with rising average fluoroquinolone consumption. This study provides direct genomic evidence that national-level antibiotic stewardship can drive the replacement of highly resistant sublineages with moderately resistant ones. These findings offer crucial scientific evidence for evaluating the impact of antibiotic management policies and inform strategies for the rational use of antimicrobials.

China

Cryo-EM structure of TGFBIp fibrils driven by a corneal dystrophy-linked mutation enables design of peptide inhibitors of aggregation.

Corneal dystrophy is a heterogeneous group of diseases which manifests clinically by progressive corneal opacity and diminishing visual acuity. A group of corneal dystrophies are linked to autosomal dominant mutations in transforming growth factor &#x3b2;-induced protein (TGFBIp) and characterized by extracellular amyloid-positive deposits of unknown molecular structure. Here, we determined the cryogenic-electron microscopy (cryo-EM) structure of amyloid fibrils formed by the TGFBIp FAS1-4 domain with corneal dystrophy-linked mutation V624M. The L569 to N609 fibril core, which includes the Y571-R588 segment enriched in patient corneal deposits, forms symmetrical protofilaments with internal solvent channels. Leveraging this structure, we designed peptide inhibitors intended to bind onto fibril ends to block elongation, targeting the unequal growth of symmetrical protofilaments. Our G1 and H4 inhibitors exhibit concentration-dependent reduction of TGFBIp FAS1-4 aggregation as assessed by Thioflavin T, solubility fractionation, and electron microscopy. Our work illustrates how fibril structures can guide rational inhibitor design and suggests the targeting of protein aggregates as a therapeutic approach for corneal and ocular diseases.

betaIG-H3 Protein

Targeted sequencing reveals a distinct genetic alteration landscape in oral multiple primary squamous cell carcinomas.

OBJECTIVE: Oral multiple primary cancers (MPCs) are associated with poor clinical outcomes, yet their genomic characteristics remain insufficiently understood. DESIGN: Fifty-four formalin-fixed paraffin-embedded (FFPE) tumor samples from 30 patients with oral MPCs were analyzed using high-depth targeted sequencing of a customized 14-gene panel derived from prior whole-exome sequencing data. Detected alterations were analyzed after removal of synonymous mutations. RESULTS: Non-silent genomic alterations were identified in 59.3% (32/54) of samples, involving 19 patients. A total of 70 variant loci across 13 genes were detected. AKAP13 was the most frequently mutated gene at both the sample (22.2%, 12/54), with recurrent mutations observed across multiple patients. In contrast, TP53 mutations occurred at a substantially lower frequency (11.1%, 6/54). Marked inter- and intra-patient mutational heterogeneity was observed. CONCLUSIONS: FFPE-based targeted sequencing enabled an initial characterization of genomic alterations in oral MPCs. Recurrent alterations in AKAP13, GLI2, JMJD1C, and DNAH8, together with the relatively low frequency of TP53 alterations, identify candidate genomic features for further investigation and provide a basis for future studies of the molecular basis of oral MPCs.

Humans

Azithromycin-resistant Salmonella enterica Typhi with AcrB R717L/Q mutations in the United States.

BACKGROUND AND OBJECTIVES: Azithromycin is a critical oral treatment for typhoid fever caused by Salmonella enterica serovar Typhi (Salmonella Typhi), since XDR has rendered other first-line treatment options ineffective. Azithromycin resistance conferred by amino acid changes in AcrB, an AcrAB-TolC efflux pump component, represents an emerging public health concern. Leveraging phenotypic and genotypic data from U.S. Salmonella Typhi surveillance systems, this study describes the prevalence, phenotype and genomic epidemiology of Salmonella Typhi with AcrB mutations in U.S. patients since the first detection in 2015. METHODS: AST and WGS data of >3000 Salmonella Typhi isolates were used to identify all cases with an AcrB mutation in the United States (2015-2025). We calculated annual prevalence and MIC ranges. Phylogenetic analysis was used to contextualize U.S. cases of Salmonella Typhi with an AcrB mutation within all globally reported cases. RESULTS: While the prevalence of AcrB mutations in the United States is low (1.5%), it has risen significantly in recent years, from 0.2% in 2016-2022 to 2.2% in 2023-2025. This increase is predominantly driven by clonal expansion of existing strains circulating in South Asia. AcrB mutations do not reliably confer resistance to azithromycin (MIC&#x200a;&#x2265;&#x200a;32&#x2005;mg/L), complicating clinical interpretation. CONCLUSIONS: The prevalence of AcrB mutations in Salmonella Typhi is increasing in the United States, and likely globally, given that U.S. data function as an informal proxy for regions without routine surveillance infrastructure. Clinical outcomes data are needed to inform Salmonella Typhi treatment guidelines and potentially amend clinical breakpoints for azithromycin.

Journal Article

Clinical and genetic features of Ph-negative myeloproliferative neoplasms with dual-driver gene positivity.

OBJECTIVES: To investigate the clinical laboratory characteristics and gene mutation features of dual-driver gene positivity in patients with Philadelphia chromosome-negative myeloproliferative neoplasm (Ph-negative MPN). METHODS: We conducted a retrospective analysis of clinical data and genetic test results from 203 newly diagnosed patients with Ph-negative MPN. Of these, 194 had single-driver gene positivity and 9 had dual-driver gene positivity. High-throughput sequencing was used to detect mutations in JAK2, CALR, and MPL. Clinical characteristics and gene mutation profiles were compared between the two patient groups. RESULTS: The incidence of dual-driver gene positivity was 4.4% (9/203), with the most common combinations being JAK2 with CALR (4 patients) and JAK2 with MPL (4 patients). Compared with the single-driver group, the dual-driver group had a significantly higher risk of bleeding [4.1% (8/194) vs. 33.3% (3/9), P&#x2009;=&#x2009;0.008] and a higher proportion of uncommon mutations [3.6% (7/194) vs. 33.3% (3/9), P&#x2009;=&#x2009;0.006]. No statistically significant differences were observed between the two groups regarding age, thrombosis incidence, splenomegaly, or routine blood test indicators. During follow-up, 1 patient in the dual-driver group died from cerebrovascular disease. No leukaemia transformation or disease-related deaths occurred among the remaining patients. DISCUSSION: The increased bleeding risk in dual-driver patients may be related to a higher proportion of CALR mutations, elevated platelet counts, and higher variant allele frequencies, though these findings require validation in larger cohorts due to the small sample size. The higher prevalence of uncommon mutations suggests a more complex mutational landscape in this subgroup. CONCLUSION: Patients with Ph-negative MPN and dual-driver gene positivity may have a higher risk of bleeding and a more complex gene mutation profile.

Humans

Osimertinib With or Without Chemotherapy in Advanced Non-Small Cell Lung Cancer With EGFR and Concurrent TP53 Mutations: A Randomized Clinical Trial.

IMPORTANCE: Combination therapy has emerged as a promising therapeutic approach for patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). However, its clinical benefit-risk profile remains a focus of ongoing debate. Identifying patients most likely to derive benefit from such regimens remains an unmet clinical need. OBJECTIVE: To prospectively compare the efficacy and safety of first-line osimertinib plus chemotherapy with osimertinib monotherapy for patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. DESIGN, SETTING, AND PARTICIPANTS: A multicenter, randomized, open-label, phase 3 study conducted at 17 sites in China. Between March 25, 2021, and July 11, 2024, a total of 294 eligible patients with treatment-naive, stage IV or recurrent nonsquamous NSCLC harboring concurrent TP53 and EGFR-sensitizing mutations were enrolled. INTERVENTIONS: Patients were randomized (1:1) to receive osimertinib plus chemotherapy (pemetrexed and carboplatin every 3 weeks for 4 cycles, followed by maintenance therapy of osimertinib plus pemetrexed; n&#x2009;=&#x2009;146) or osimertinib monotherapy (n&#x2009;=&#x2009;148). MAIN OUTCOMES AND MEASURES: The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, response, safety, and quality of life. RESULTS: Among 294 enrolled patients, the median age was 57 years (range, 26-79 years), and 159 (54.1%) were female. The data cutoff date was November 11, 2025. At a median follow-up of 25.1 months for the osimertinib-chemotherapy group and 26.1 months for the osimertinib monotherapy group, median progression-free survival was significantly longer with osimertinib plus chemotherapy than with osimertinib monotherapy (34.0 vs 15.6 months; difference, 18.4 months [95% CI, 9.9-22.3]; hazard ratio, 0.44 [95% CI, 0.32-0.60]; P&#x2009;<&#x2009;.001). This benefit was consistent across prespecified subgroups, including those with brain metastases and L858R mutations. The overall survival data remained immature (30.6% maturity); however, a trend toward overall survival benefit with combination therapy was observed. The incidence of grade 3 or higher treatment-related adverse events was higher in the combination group, with no new safety signal identified. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, osimertinib plus chemotherapy significantly increased progression-free survival among patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. These findings provided a clinical rationale for individualized combination strategies in the management of patients with EGFR-mutated NSCLC. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04695925.

Adult

Tracking microplastic contamination across seasons in a freshwater reservoir: Evidence from surface water, sediments, and fishes.

Microplastics (MPs) are prevalent contaminants in aquatic environments, posing substantial ecological and health risks. These particles migrate within the different layers of aquatic bodies with time and affect the respective biota. Thus, to get an in-depth understanding of the particles, this current study investigated the seasonal distribution, morphological and chemical characteristics, along with potential ecological and human health impacts in the samples including surface water, sediment, and fish from a drinking water supplying reservoir in eastern India. Across three different seasons, pre-monsoon, monsoon, and post-monsoon samples were collected using optimized methods. Results revealed distinct seasonal trends: MP abundance in surface water peaked during the monsoon (mean: 1.15 MPs/L), while sediment showed the highest concentrations in the pre-monsoon (mean: 596 MPs/kg), indicating temporal accumulation dynamics influenced by runoff, hydrodynamics, and sedimentation. Fish gut analysis confirmed ingestion of MPs across five species, with concentrations ranging from 26 to 100 MPs/kg, depending on feeding habits. The most dominant MP type were fragments, followed by fibers, films, and beads. Polymer analysis via &#xb5;FTIR identified polyethylene, polypropylene, and polyvinyl chloride as prevalent, with hazard assessments (i.e., Polymer Hazard Index (PHI)) indicating medium to very high ecological risks. Heavy metal association was more dominant in the MPs isolated from sediments than the waterborne MPs. Pollution Load Index (PLI) values were > 1 in most seasons, confirming contamination. Health risk analysis suggested potential exposure through both drinking water and fish consumption. This study emphasizes the need for seasonal monitoring, improved waste management, and mitigation strategies to address MP pollution in freshwater ecosystems.

Microplastics

Genetic mutations driving ciprofloxacin resistance in laboratory-evolved Salmonella Typhimurium.

Ciprofloxacin resistance in Salmonella Typhimurium is a significant public health concern, and the mechanisms by which the resistance evolves are poorly defined. Here, by serial passaging under antibiotic selection, we isolated ciprofloxacin-resistant S. Typhimurium mutants and subjected them to whole-genome sequencing to reveal the major mutations associated with resistance. The Low CipR mutant acquired four chromosomal mutations in ramR, icdA, lipB, and gyrA, and the High CipR mutant gained additional mutations in gyrB, yaiC, and corA. Functional characterization determined that mutations in ramR resulted in efflux pump upregulation, while disruptions in the TCA cycle caused by mutations in icdA and lipB led to metabolic alterations. These changes indirectly enhanced resistance by increasing the expression of the global regulator MarA and reducing OmpF-dependent membrane permeability. Despite the observation of the G105A substitution in GyrA, enzymatic assays confirmed the failure to support resistance to ciprofloxacin, possibly because the structural alteration remained minimal. GyrB488-489dup was associated with maintained supercoiling under ciprofloxacin and enhanced fluoroquinolone resistance, suggesting a major role in resistance evolution. Other mutations in yaiC impaired biofilm and, in corA, intracellular accumulation of magnesium, possibly stabilizing the bacterial cell envelope under antibiotic pressure. The findings provide novel explanations for the multifaceted mechanisms leading to ciprofloxacin resistance in Salmonella and suggest targets to combat antimicrobial resistance.IMPORTANCEAntibiotic resistance in Salmonella Typhimurium is an increasing public health concern, yet the genetic changes that allow bacteria to become resistant are not fully understood. In this study, we evolved ciprofloxacin-resistant Salmonella in the laboratory and identified the mutations that arise during resistance development. We found that resistance does not result from a single change but from multiple adaptations affecting drug efflux, metabolism, and the antibiotic target. Some mutations increased the activity of pumps that remove antibiotics from the cell, while others altered bacterial metabolism and reduced membrane permeability, making it harder for the drug to enter. A duplication in the DNA gyrase subunit GyrB played a particularly important role in maintaining DNA function under antibiotic stress. Together, these results reveal how diverse genetic changes cooperate to generate ciprofloxacin resistance and provide insights that may help guide strategies to combat drug-resistant Salmonella infections.

DNA gyrase