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Effectiveness of an educational video for caregivers of children with neurogenic bladder: A randomized controlled trial.

BACKGROUND: The complexity of neurogenic bladder (NGB) management underscores the importance of caregiver education, yet high-quality education materials remain scarce. This study aims to assess the effectiveness and acceptability of an educational video designed to improve knowledge about NGB among caregivers of children with this condition. METHODS: We identified English-speaking caregivers of patients aged zero to 18 years, diagnosed with NGB, without prior major bladder reconstructive surgery, who received care at our institution from 2018 to 2022. Caregivers were randomly assigned into control or video groups using a block randomization model based on age. The control arm completed a six-item knowledge assessment before viewing the video, while the video group watched the video first. All participants rated the video's acceptability. Qualitative analysis of the open-ended responses to the acceptability questionnaire followed principles of thematic analysis. RESULTS: Of 409 eligible participants, 106 (25.9%) completed the study. Video (n = 48) and control (n = 58) groups were demographically similar. In the video group, 64.6% answered correctly all questions in the knowledge questionnaire, compared to 31% in the control group. After adjusting for patient age, caregivers in the video group were more likely to answer any question in the knowledge assessment correctly (relative probability: 1.13, 95% CI [1.06, 1.21], p < 0.01). Evidence for a difference in correct response rate among individual questions was strongest for question #1, which asked about common urological conditions for which NGB patients are at higher risk (95.8% vs. 79.3%, p = 0.01), and question #6, which asked about indications for bladder surgery (87.5% vs. 67.2%, p = 0.01), with the video group more likely to answer correctly for both questions. Qualitative analysis identified three major themes regarding parents' acceptance of the educational video: 1) attitudes towards video content and presentation, 2) usefulness of video as an educational tool, and 3) future directions. CONCLUSIONS: Our study found that an educational video about NGB effectively enhanced parental understanding of the condition and was deemed acceptable by parents as an introductory educational tool. The literature shows the benefit of using technology and visual aids to enhance health literacy for patients and caregivers, a key first step towards optimizing health outcomes for pediatric urologic patients.

Humans

Single nucleus multiomics reveals an early inflammatory response to high-fat diet in mouse islets.

In periods of sustained hyper-nutrition, pancreatic &#x3b2;-cells undergo functional compensation through transcriptional upregulation of gene programs driving insulin secretion. This adaptation is essential for maintaining systemic glucose homeostasis and metabolic health. Using single nuclei multiomics, we have mapped the early transcriptional adaptive mechanisms in murine islets of Langerhans exposed to high-fat diet (HFD) for 1 and 3 wk. We show that &#x3b2;-cells exhibit the largest transcriptional response to HFD, characterized by early activation of pro-inflammatory eRegulons and down-regulation of &#x3b2;-cell identity genes, particularly in a distinct subset of &#x3b2;-cells. These observations extend to humans, where the prevalence of an &#x3b2;-cells with a high inflammatory signature is increased in diabetes. Collectively, these observations point to cellular crosstalk through pro-inflammatory signaling as a central and early driver of &#x3b2;-cell dysfunction that limits the compensatory capacity of &#x3b2;-cells, which is closely linked to the development of diabetes.

Animals

Once-weekly IcoSema versus once-daily insulin glargine U100 in type 2 diabetes management (COMBINE 4): an open-label, multicentre, treat-to-target, randomised, phase 3b trial.

BACKGROUND: Stepwise treatment intensification is recommended for managing type 2 diabetes, including insulin initiation when non-insulin glucose-lowering medications are insufficient. Guidelines recommend combining a GLP-1 receptor agonist with basal insulin to improve glycaemic efficacy while reducing weight gain and hypoglycaemia risk. COMBINE 4 evaluated the efficacy and safety of IcoSema, a once-weekly combination therapy of basal insulin icodec and semaglutide (a GLP-1-receptor agonist) versus insulin glargine U100 (glargine U100) in people with type 2 diabetes on oral glucose-lowering medications. METHODS: COMBINE 4 was a 40-week, randomised, open-label, treat-to-target, phase 3b trial conducted across 97 sites in nine countries. Adults (aged &#x2265;18 years) with type 2 diabetes (HbA1c &#x2265;8&#xb7;0%) receiving oral glucose-lowering medications were randomly allocated in a 1:1 ratio without stratification to IcoSema or once-daily glargine U100. The titration target was 3&#xb7;9-5&#xb7;0 mmol/L (70-90 mg/dL). The primary endpoint was change in HbA1c and the secondary confirmatory endpoint was change in bodyweight, both from baseline to week 40, evaluated in all randomly allocated participants. Adverse events were recorded during weeks 0-45. This trial is registered with ClinicalTrials.gov (NCT06269107) and is complete. FINDINGS: Of 653 individuals screened between Feb 15 and Aug 6, 2024, 151 did not meet screening criteria and 17 withdrew before initiating treatment; 243 were randomised to IcoSema and 242 to glargine U100. Of the 485 randomly allocated participants, 286 (59%) were male and 199 (41%) were female, and median age was 58 years (range 26-82). For HbA1c, from baseline (9&#xb7;57% for IcoSema and 9&#xb7;50% for glargine U100), mean change to week 40 was greater with IcoSema versus glargine U100 (-3&#xb7;32 vs -2&#xb7;44 percentage points; estimated treatment difference [ETD] -0&#xb7;88 percentage points [95% CI -1&#xb7;12 to -0&#xb7;63]), confirming superiority of IcoSema (p<0&#xb7;001). From baseline to week 40, mean bodyweight decreased with IcoSema and increased with glargine U100 (-0&#xb7;79 vs 3&#xb7;81 kg; ETD -4&#xb7;61 kg [95% CI -5&#xb7;46 to -3&#xb7;75]), confirming superiority of IcoSema (p<0&#xb7;001). Rate of combined clinically significant (blood glucose <3&#xb7;0 mmol/L [<54 mg/dL], confirmed with a blood glucose meter) or severe hypoglycaemia (severe cognitive impairment requiring external assistance for recovery) was statistically significantly lower with IcoSema versus glargine U100 (0&#xb7;29 vs 0&#xb7;59 episodes per person-year of exposure; estimated rate ratio 0&#xb7;56 [95% CI 0&#xb7;32 to 0&#xb7;97]; p=0&#xb7;04). Gastrointestinal disorders were the most frequently reported adverse events with IcoSema. INTERPRETATION: Once-weekly IcoSema demonstrated superior HbA1c reduction and bodyweight change, with lower rates of clinically significant or severe hypoglycaemia, versus glargine U100, suggesting that IcoSema might be an effective once-weekly treatment option for insulin-naive individuals with type 2 diabetes inadequately controlled on oral glucose-lowering medications. FUNDING: Novo Nordisk.

Humans

Flux rewiring enables native D-glucosamine production in Escherichia coli.

D-Glucosamine is an industrially important amino sugar used in pharmaceuticals, nutraceuticals, and functional materials, yet its production remains dominated by chemical extraction from chitinous biomass, raising sustainability and allergen concerns. Escherichia coli natively synthesizes D-glucosamine directly from D-glucose through endogenous metabolism, revealing an underutilized amino sugar biosynthetic capability. Building on this native pathway, D-glucosamine production was enhanced through targeted genetic modifications and systematic optimization of nitrogen metabolism and cultivation conditions, reaching 9.2&#x202f;g&#x202f;L-1 under shake-flask conditions. This work extends a phosphorylation-dephosphorylation strategy previously developed for neutral rare sugars to amino sugar biosynthesis, demonstrating the broader applicability of this metabolic design principle. Phosphatase identity emerged as a key control point for product formation: YbiV was the most effective phosphatase for selective D-glucosamine production, whereas alternative phosphatases redirected flux toward D-sedoheptulose. This enzyme-dependent flux partitioning further enabled tunable co-production of D-glucosamine and D-sedoheptulose. Native amino sugar biosynthesis in E. coli provides a controllable framework for producing chemically distinct sugars through endogenous metabolism and establishes a generalizable strategy for engineering amino sugar and other nitrogen-containing metabolite biosynthesis.

Escherichia coli

Nephropathies Associated with Sickle Cell Trait and How to Study Them.

Sickle cell trait (SCT), which carries a single point mutation in the hemoglobin-&#x3b2; (HBB) gene, has long been considered a benign condition. However, epidemiological evidence challenges this assumption, revealing that individuals with SCT face an elevated risk of renal dysfunction. However, this field of study remains ill-defined as it has focused on sickle cell disease (SCD), where renal complications are severe. As SCT is more prevalent than SCD, consequences of nephropathies in this group translate into a substantial and largely unaddressed public health burden. Clinical data, primarily observational, implicate age and sex in the development of SCT-associated nephropathies. These manifestations span glomerular hyperfiltration, tubular damage, hematuria, renal papillary necrosis, renal medullary carcinoma, and progression to chronic kidney disease, all complications that cluster disproportionately in older male individuals. Despite this, the mechanistic basis of SCT nephropathy, the thresholds at which renal injury becomes clinically significant, and the optimal strategies for early identification and prevention remain inadequately defined. In vitro studies have primarily focused on SCD blood cell biology, with SCT receiving comparatively little attention. Humanized murine models (i.e., Berkeley and Townes) have recapitulated some SCT-associated renal phenotypes but need to be more fully characterized. This review aims to provide an overview of the biology of sickle cell trait nephropathies, the gaps in our knowledge, and the model systems we can use to fill those gaps.

Journal Article

Messaging Strategies for Tobacco Prevention and Cessation Among People with Depression: A Scoping Review.

INTRODUCTION: Depression is strongly associated with higher tobacco use and lower quit rate; few communication campaigns have been designed with these mental health factors in mind. This scoping review compiles existing research on tobacco prevention and cessation messaging involving people with depression to identify gaps and opportunities for future message development. METHODS: Sources included PubMed, PsycINFO, Scopus, Academic Search Premier, and ProQuest Central (November - December 2024). The 55 studies included examined tobacco prevention or cessation messages and measured depression, depressive symptoms, or mental health as a primary outcome or analytic covariate. Study characteristics, target population, delivery format, message content, theoretical frameworks, outcomes, and gaps were extracted. RESULTS: RCTs made up half (51%) of the included studies, and most (78%) were conducted in the U.S. Nearly half (46%) required participants to have a mental health condition. Interventions most often used interactive (65.5%) or text-based (47.3%) communication and focused on tobacco cessation (89%) rather than vaping (9%). Common outcomes included feasibility or acceptability (37.7%) and point prevalence abstinence (37.7%). Mental health-specific messages showed mixed effectiveness. CONCLUSIONS: Despite progress in integrating mental health into tobacco messaging, targeted interventions for people with depression remain limited. Few studies tested long-term outcomes or used biochemical verification; many relied on untargeted generalized messaging.

Journal Article

Symptoms and treatment response to florensocatib and inhaled tobramycin in bronchiectasis: Post hoc analysis of two randomized trials.

Inhaled antibiotics and DPP-1 inhibitors improve clinical outcomes in bronchiectasis, but whether baseline symptom burden predicts differential treatment responses remains unclear. In this post hoc analysis of two multicenter randomized trials (SAVE-BE, n = 224; TORNASOL, n = 357), we evaluate the association between baseline Quality of Life-Bronchiectasis Respiratory Symptom Scale (QoL-B-RSS) and treatment effects of florensocatib and inhaled tobramycin. In SAVE-BE, florensocatib reduces exacerbation rates versus placebo (relative risk [RR], 0.47; 95% confidence interval [CI], 0.33-0.67; p < 0.0001), with RRs of 0.53 and 0.40 observed in patients with high and low symptom burdens, respectively, but no significant symptomatic improvement. In TORNASOL, tobramycin produces clinically meaningful QoL-B-RSS improvements (exceeding the 8-point cutoff in high-symptom patients) and ameliorates bronchitic symptoms, with greater benefits in those with higher baseline symptom burden. These hypothesis-generating findings suggest that baseline symptom burden may identify differential responses to anti-inflammatory versus anti-infective therapies in bronchiectasis and support its potential as a simple, practical stratification tool to guide personalized treatment.

Humans

Sarcomas: Research on Ultrarare Subtypes Gains Ground.

Rare cancers account for almost one fourth of all cancers. Sarcomas belong to the group of cancerous diseases with an incidence of less than 6 cases per 100,000 inhabitants. Over the past decade, activities were launched worldwide to elucidate the peculiarities of many of the more than 100 sarcoma subtypes described in the World Health Organization handbook. The major contributor to exact diagnosis is molecular pathology. The subgroup of ultrarare sarcomas (URS) poses a significant problem as each URS type has its own morphology, biology, natural history, and prognosis. In 2020, 35 international sarcoma centers agreed to standards of evaluating URS. The threshold was set to an incidence of less than 1 case per 1,000,000 inhabitants, and 77 URS subtypes were defined. Also quality criteria for centers to be selected for retrieving data to registries were consented. This issue of Cancer Epidemiology, Biomarkers & Prevention contains the first article to validate these principles of URS using the data from a nationwide cancer database. The authors from Taiwan also pointed out limitations of the approach. Combination with the national death database allowed to calculate overall survival (OS) and identified age as a significant factor for OS per URS type. These new data might foster future research on diagnosis and treatment of URS. See related article by Lee et al., p. 1654.

Humans

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

Recent advances in Strongyloides screening, diagnostics, therapeutics, and management.

PURPOSE OF REVIEW: Strongyloidiasis affects an estimated 30-100 million people globally and can have life-threatening consequences in immunocompromised hosts, yet it remains underdiagnosed due to limited access and performance of available diagnostics. Novel assays and anthelmintics may reshape screening, diagnosis, treatment, and prevention for at-risk populations. RECENT FINDINGS: Advances in molecular diagnostics coupled with robust stool extraction methods have supplanted traditional parasitologic methods in settings where nucleic acid amplification is feasible. Transition from standard immunoglobulin G (IgG)-based immunoassays to the new IgG- and IgG4-based rapid diagnostic tests using recombinant Strongyloides stercoralis nematode immunodominant E antigen (NIE) and/or S. stercoralis immunoreactive antigen (SsIR) has facilitated serologic screening at the point of care. The World Health Organization now conditionally recommends community-wide ivermectin mass drug administration in highly endemic settings. Regarding new treatment options, moxidectin is noninferior to ivermectin with 93-94% cure rates and a longer half-life, while emodepside shows 80-90% predicted cure rates in early trials and offers a mechanistically distinct option. Understanding of immunosuppressed populations at risk for hyperinfection has expanded, prompting updated screening recommendations. SUMMARY: Serologic and molecular tools are improving screening and diagnosis, and moxidectin and emodepside may broaden treatment options, but data in severe disease and special populations remain limited. Priorities include harmonized screening algorithms and prospective studies in high-risk groups.

Humans

Psychological skills training for sport-related outcomes: An umbrella review of evidence credibility and methodological quality.

Psychological skills training (PST) is widely used in sport, but review-level evidence remains fragmented across interventions, populations, outcomes, and methodological standards. This umbrella review synthesized evidence on PST-related interventions for sport-related outcomes, including athletic performance, psychological outcomes, cognitive performance, and sports injury, and evaluated evidence credibility, certainty, and methodological quality. A systematic literature search was conducted on 21 May 2025 in MEDLINE, PsycInfo, PubMed, Scopus, SportDiscus, Web of Science, and CINAHL Complete. Overall, 61 reviews involving 42,106 participants were included; 35 meta-analyses involving 28,076 participants were eligible for quantitative synthesis, and 26 reviews or meta-analyses involving 14,030 participants were summarized qualitatively. Quantitative findings showed generally positive point estimates for mindfulness-based interventions, imagery practice, music-based interventions, neurofeedback, perceptual-cognitive training, and multiple PST interventions, but most findings were weak or non-significant and certainty was generally very low. Qualitative evidence suggested potential benefits, but conclusions varied according to intervention definition, delivery, outcome measurement, and methodological quality. Evidence was more developed for athletic performance and psychological outcomes than for cognitive performance and sports injury. Overall, PST-related interventions may benefit sport-related outcomes, but conclusions should remain cautious because of low certainty, methodological heterogeneity, and limited evidence credibility.

Humans

A systematic review of human avoidance learning: Cognition, computation, and methods.

Avoidance behaviour is fundamental for survival but can become maladaptive in clinical conditions. A large body of literature has accumulated on the dynamics of human avoidance learning. However, current theories and overviews do not provide an exhaustive account of this evidence. In this systematic review, we identify N = 116 studies on human avoidance learning. We analyse these studies with the goal of distilling robust empirical phenomena as a basis for theory-building, and examine their diagnostic value in differentiating between competing theories. We find that the evidence is difficult to reconcile with foundational two-factor and classical safety-signal accounts, and most strongly supports expectancy- and inference-based views, in which avoidance responses are selected with respect to represented consequences. At the same time, no current framework provides a complete account of the evidence: several findings point to an additional role for operant valuation, Pavlovian influences, and contextual or latent-state control over the expression of avoidance. Methodologically, we observe that the problem setting in the most common experimental paradigms is radically simpler than real-world avoidance and therefore unlikely to expose the limits of inferential or reflective mechanisms. Consequently, we argue that paradigms with greater computational demands and more realistic action affordances are required to identify the mechanisms underlying avoidance learning. Collectively, these insights provide a foundation for theoretical refinement, computational modelling, and methodological innovation, with implications for advancing interventions targeting maladaptive avoidance.

Humans

Ambrosia beetle invasions are structured by inbreeding, intraspecific hybridisation, and bridgeheads.

When invasive populations establish in regions far from their origin, they may accumulate deleterious mutations that limit population viability and later expansion. Invasions stemming from such bridgehead populations may experience further sequential bottlenecks. However, deleterious mutations can be masked or eliminated when populations outbreed with other lineages. Here, we analyse global invasions of a species complex of persistently inbreeding ambrosia beetles, using genomic data (N=247) from invasive populations in Africa, North America and Australia, and from native populations in Asia. We mostly focus on one species of this complex (Euwallacea fornicatus) which poses a severe threat to tree species worldwide and is rapidly expanding its global range. We uncover a single lineage of this species across California, South Africa, and Western Australia, involving an invasive bridgehead and containing almost no nuclear genetic variation. In South Africa we identify a second lineage that has repeatedly hybridised with the first lineage. Genetic patterns in the native range indicate that such opportunistic outbreeding may be common. Despite lacking nuclear variation, the first lineage contained two CO1 haplotypes that were also observed in every hybrid lineage, pointing to heteroplasmy and possible hybrid origins of this lineage. Native populations had fewer missense mutations than invasive populations, indicating that opportunistic outbreeding may help purge fixed deleterious mutations when local lineage diversity is high. These findings highlight the importance of outbreeding even when inbreeding is common, and they demonstrate the biosecurity threat posed by subsequent gene flow into invasive populations.

Journal Article

Context matters: coordinated transcriptional regulation and root plasticity under multinutrient conditions.

Plants often encounter simultaneous imbalances in multiple nutrients, but the regulatory logic coordinating their responses remains poorly understood. We aimed to uncover shared transcriptional programs and regulatory nodes underpinning multinutrient adaptation in Arabidopsis thaliana roots. We analyzed publicly available RNA-seq datasets spanning 15 nutrient and beneficial element conditions using differential expression, co-expression network (WGCNA), and gene regulatory network analysis. Selected transcription factors (TFs) were validated via root phenotyping, suberin staining, and ionomic profiling under two-nutrient stress conditions. We identified a core set of 2050 genes responsive to multiple nutrient treatments, enriched for suberin biosynthesis, and structured into modular co-expression clusters. Eight prioritized candidate TFs (ARR10, GBF3, HHO5, NAC32, NF-YA3, NF-YB2, SARD1, and WRKY33) were&#xa0;shown to modulate root system architecture under specific nutrient combinations. WRKY33 and NF-YB2, in particular, regulated nutrient-responsive suberin deposition and ionomic plasticity. These findings reveal suberin remodeling as a shared downstream process in multinutrient responses and suggest that plasticity is not a fixed trait but a modular, polygenic, and context-dependent outcome. Repurposed TFs with pleiotropic functions coordinate structural and physiological traits, providing regulatory entry points for improving nutrient resilience.

Plant Roots

Malaria rapid diagnostic tests: performance, pitfalls, and progress.

PURPOSE OF REVIEW: Malaria rapid diagnostic tests (RDTs) have revolutionized malaria diagnosis in endemic settings. RDTs are simple to use and accurate for clinical cases, although sensitivity is reduced at parasite densities below 200&#x200a;parasites/&#x3bc;l. However, increasing prevalence of hrp2/3 gene deletions in certain areas threaten utility of histidine-rich protein 2 (HRP2)-based RDTs, and lingering HRP2 antigenemia can generate false-positive results after parasite clearance. This review summarizes current performance of malaria RDTs, threats to their validity, and recent innovations to improve their performance and continued role in malaria diagnosis. RECENT FINDINGS: Most World Health Organization (WHO) prequalified RDTs perform well for clinical diagnosis, with only occasional exceptions, including a recently reported issue affecting several countries. RDT sensitivity is generally related to malaria transmission intensity, with higher proportions of false-negative results in lower-transmission areas. Newly prequalified lactate dehydrogenase (pLDH)-based RDTs perform well for both Plasmodium falciparum in areas with >5% hrp2/3 gene deletions&#xa0;and for Plasmodium vivax diagnosis. Several point-of-care alternatives to RDTs, including micro-fluidic devices, hemozoin-detecting devices, and automated hematology analyzers, have shown promising results in small studies, but require larger-scale trials before widespread use. SUMMARY: RDTs remain a critical tool in clinical diagnosis of malaria, and newer pLDH-based tests perform well in areas where hrp2/3 gene deletions threaten validity of HRP2-based RDTs.

Humans

Uncovering hidden complexity in the Apis mellifera mitotranscriptome: a polyadenylation-centered perspective.

Mitochondrial transcription is gaining increasing attention as researchers seek to better understand the full coding potential of mitochondrial DNA (mtDNA). Emerging evidence suggests that mtDNA may encode additional elements beyond classical oxidative phosphorylation genes, pointing to a more complex transcriptional architecture than previously recognized. In this study, we explored the mitochondrial transcriptome of Apis mellifera (Insecta: Hymenoptera), with a particular focus on polyadenylation-associated features. Our analysis revealed that both sense and antisense transcripts undergo polyadenylation, although transcript abundance and poly(A) tail lengths varied markedly across mitochondrial genes. Several transcripts exhibited alternative isoforms, either extended or truncated, frequently including intergenic regions. These regions may represent functional non-coding elements or structural variants rather than conventional untranslated regions (UTRs). Interestingly, some transcripts also contained non-templated nucleotide additions particularly cytosine residues immediately upstream of the poly(A) tails. Monocistronic units that included portions of downstream intergenic regions were among the most abundantly represented, suggesting a possible regulatory role for these sequences. To experimentally validate our in silico findings, we performed RT-qPCR to assess relative gene expression and applied 3' RACE-PCR to define transcript boundaries. These approaches confirmed the presence of multiple transcript isoforms and supported the involvement of polyadenylation in shaping mitochondrial RNA diversity. Together, our findings reveal a previously underappreciated level of complexity in the A. mellifera mitochondrial transcriptome and highlight the potential regulatory significance of polyadenylation dynamics and intergenic region transcription.

Animals

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

Longitudinal Relations among Perceived Economic Stress, Teacher-Student Relationships, and Cybervictimization: Exploring Within-Person Links.

Family economic hardship has been identified as a risk factor for adolescents' cybervictimization. Nevertheless, existing studies have primarily focused on objective economic conditions, and little is known about the within-person association between perceived economic stress and adolescents' cybervictimization and the mediating mechanisms underlying this association. To fill these gaps, the random intercept cross-lagged model was employed to examine the dynamic relations among perceived economic stress, teacher-student relationships, and cybervictimization. The data were obtained from a sample of 2407 Chinese adolescents (Mage = 12.75, SD = 0.58, 50.23% girls at baseline) recruited from seven schools and assessed at three time points over one year. At the between-person level, there were no significant associations among perceived economic stress, teacher-student relationships, and cybervictimization. At the within-person level, perceived economic stress positively predicted later cybervictimization over time, and this effect was unidirectional. The bidirectional relations between perceived economic stress and teacher-student relationships remained stable over time. Cybervictimization significantly and negatively predicted subsequent teacher-student relationships across time, indicating a unidirectional predictive effect. Additionally, perceived economic stress indirectly predicted cybervictimization through teacher-student relationships. The findings highlight the importance of distinguishing within-person from between-person processes and shed light on the longitudinal role of teacher-student relationships in the association between perceived economic stress and cybervictimization.

Humans