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PubMed2026

Cochlear size variation in a large-scale international multicentre cohort.

AIM: This study aims to (1) review the literature on cochlear size, measured by the A-value, to assess reported variation across studies, and (2) consolidate cochlear parameters-specifically basal turn diameter (A-value) and width (B-value)-measured using the standardized DICOM viewer OTOPLAN®, and compare these with published data. METHODS: A scoping literature review was conducted using the search term "diameter of cochlear basal turn" to identify studies reporting A-value measurements. To complement this, cochlear measurements obtained with OTOPLAN® were collected from clinical collaborators across multiple international centres. The ratio of B- to A-values, which defines the cochlear basal turn shape, was calculated as previously described by Khurayzi et al. (2021). RESULTS: The literature review identified 38 studies comprising 5,206 A-value measurements (average: 9.08 mm; range: 8.01-10.03 mm). Additionally, 5,580 OTOPLAN® measurements were collected from 43 clinics across 25 countries (mean: 9.07 mm; range: 6.67-11.45 mm). Overall, 68.7% of cochleae exhibited an elliptical basal turn shape. CONCLUSION: Using a large, international multicentre dataset and a standardized measurement tool, this study demonstrates substantial variation in cochlear size and shape across clinical cohorts from different regions. The mean A-value (9.07 mm) is consistent with previously published literature, while the wider observed range highlights greater anatomical variability within a multicentre clinical population than previously reported. The majority of cochleae demonstrate an elliptical basal turn configuration.

Humans↗

PubMed2026

Cochlear Implantation in Sickle Cell Disease: A Systematic Review of Feasibility and Outcomes.

INTRODUCTION: Sickle cell disease (SCD) is associated with systemic complications, including sensorineural hearing loss (SNHL) from microvascular occlusion and chronic inflammation. Although reports link SCD to higher rates of SNHL, current evidence is limited by small sample size, varied audiologic methods, and lack of standardized screening. This systematic review summarizes available literature on SNHL and cochlear implantation (CI) in SCD. METHODS: A literature search of PubMed MEDLINE, Embase, Scopus, Web of Science, and CINAHL identified 79 citations. After removal of duplicates, 35 records were screened in Rayyan. Studies published between January 1, 2000, and June 30, 2025, were eligible if they reported patients with SCD who developed hearing loss and underwent CI. Nine full texts were reviewed, and 4 met the inclusion criteria. Screening and review were performed independently by 2 authors per PRISMA guidelines. RESULTS: Across 4 case reports, a total of 5 patients with SCD underwent CI, ranging in age from 2 to 42 years. Four presented with bilateral severe-to-profound SNHL and one with unilateral loss. Implantation was technically feasible in all cases, including patients with cochlear fibrosis or ossification requiring modified insertion techniques. Postoperative outcomes were favorable: all patients demonstrated reliable device function and low impedances. Only 60% showed meaningful auditory benefit, characterized by improved functional speech perception in 2 patients (40%) and access to the speech frequency range with hearing testing going from moderate/profound hearing loss to mild hearing loss in 3 patients (60%). Complications occurred in 2 patients (40%): one developed unilateral middle ear infection leading to meningitis, and another experienced a postoperative pulmonary embolism requiring anticoagulation. The remaining 3 patients (60%) had uncomplicated recoveries with reported improved hearing from moderate/profound hearing loss to mild hearing loss post implantation. CONCLUSION: While CI appears feasible in SCD, our findings suggest that additional data are needed to assess its effectiveness in this patient population. However, evidence is limited to case reports, and complications such as thromboembolism and rapid cochlear fibrosis highlight the need for close perioperative management. More comprehensive studies with larger sample size are required to define surgical risk, optimize management, and establish best practices for timely implantation in this population.

Humans↗

PubMed2026

The Soundtrack of Everyday Life: Real-world Music Listening Habits of Adult Cochlear Implant Users.

OBJECTIVE: Characterize real-world patterns of music listening and reward sensitivity among adult cochlear implant (CI) users compared with normal-hearing (NH) listeners. STUDY DESIGN: Cross-sectional observational study. SETTING: Online. PATIENTS: Adults (≥18 y) with a CI or NH who used a music-streaming platform as their primary listening method. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Objective measures included platform-derived audio features (acousticness, danceability, energy, tempo, and valence), listening volume, unique-song ratio, and decade preferences. Self-reported measures included listening habits and the Barcelona Music Reward Questionnaire (BMRQ). Group comparisons used ANCOVAs and mixed-effect models adjusting for age and gender; within-CI analyses compared prelingual versus postlingual deafness. RESULTS: Among 16 CI users (69% male, 39.0±15.6 y) and 29 NH listeners (38% male, 32.2±11.3 y), CI users demonstrated a higher unique-song ratio (β=-0.157, CI as reference; 95%CI [-0.281, -0.034]; P =0.014) and stronger preference for older music (Pillai trace=0.537; F8,35 =5.07; P <0.001), adjusting for age. No significant group differences were observed in weekly listening time, listening volume, audio features, or BMRQ scores (total and subscores). Equivalence was confirmed for Emotion Evocation and Sensory-Motor subscales. There were no statistically significant differences in listening environments after Holm correction. No statistically detectable differences were observed between pre- and postlingually deafened CI users. CONCLUSIONS: Musically active CI users showed no significant differences in listening volume or overall music-reward sensitivity compared with NH peers, but demonstrated higher unique-song ratios and a bias toward older music. Findings highlight the value of ecologically valid data in understanding real-world music experiences among CI users.

Adult↗

PubMed2026

Assessment of Surgical Salvage Outcomes for Exposed Cranial Neuromodulating Devices.

OBJECTIVES: Implanted neuromodulating devices (NMDs) such as cochlear implants (CIs) and deep brain stimulators (DBSs) are commonly used in modern medicine. Rarely, complications arise post-operatively, including hardware exposure. Traditional teaching suggests that these devices require removal if exposed; however, surgical salvage is a high risk, high reward alternative. We review our single institution experience managing NMD exposure with surgical salvage. METHODS: Retrospective chart review was performed on individuals who had a NMD implanted and underwent an attempt at surgical salvage for exposure during the study period (January 01, 2021 through December 31, 2023). Study outcome success was defined as maintaining a functional NMD 1 year after salvage was attempted. Surgical techniques associated with successful salvage were compared. RESULTS: Nine of 729 patients (1.2%) implanted with NMDs experienced hardware exposure during this 2-year study period. Nine subjects were referred for NMD salvage; however, only 6 of 9 subjects (66.7%, CI = 3; DBS = 3) underwent NMD salvage attempts. Four of the subjects had successful salvage demonstrated successful salvage with a functioning NMD and without wound healing concerns 1 year after their salvage procedure. CONCLUSIONS: Classic teaching states that exposed NMDs require explantation. However, this approach necessarily imposes time without benefit from the NMD between explantation and reimplantation. Our experience demonstrates that surgical salvage can be a successful alternative for the majority (66.7%) of individuals.

Humans↗

PubMed2026

Auditory brainstem response in the identification of cochlear synaptopathy in aged rodents: a systematic review with meta-analysis.

PURPOSE: This systematic review and meta-analysis evaluated the diagnostic performance of auditory brainstem response (ABR) for identifying age-related cochlear synaptopathies in rodents. METHOD: Following PRISMA guidelines, searches were conducted in PubMed/MEDLINE, Cochrane Library, Scopus, Embase, Web of Science, SciELO, LILACS, and gray literature. Studies evaluating CS in naturally aged rodents using short-latency auditory evoked potentials (AEPs) were included. Study selection, data extraction, risk-of-bias (JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies), and certainty of the evidence (GRADE® system) assessment were conducted independently by two reviewers. Meta-analyses were performed using a random-effects model, with standardized mean differences and 95% confidence intervals. ABR wave I amplitudes were analyzed for click (80 and 90 dB SPL) and tone-burst stimuli stratified by frequency. RESULTS: Among 3,008 identified records, 12 studies were included in the review and five in the meta-analysis. All included studies used ABR measures to investigate CS, with wave I amplitude being the most frequently evaluated biomarker. Meta-analysis demonstrated a significant reduction in ABR wave I amplitude in aged rodents compared with young controls for both click- and tone-burst-evoked responses. Tone-burst ABR showed no significant differences among the evaluated frequencies. These findings should be interpreted with caution due to the limited number of studies and the methodological heterogeneity, which may have reduced statistical power and comparability. CONCLUSIONS: The evidence supports ABR wave I amplitude as a sensitive electrophysiological marker of age-related CS in rodents. Nevertheless, further studies with standardized protocols are needed to strengthen its diagnostic utility and improve comparability across studies.

Animals↗

PubMed2026

Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of auditory nerve output after threshold recovery.

BACKGROUND: Acoustic stress can alter cochlear function even in the absence of permanent threshold elevation; however, synaptic consequences of transient acoustic stimulation remain incompletely understood. OBJECTIVE: This study aimed to investigate whether transient acoustic stimulation induces changes in the auditory nerve output and cochlear ribbon synapse morphology following hearing threshold recovery. METHODS: Young adult CBA/CaJ mice were exposed to band-limited acoustic stimulation (45-2,000 Hz, 95 dB SPL, 2 h). Auditory brainstem responses (ABRs), hair cell and spiral ganglion neuron survival, and synaptic morphology were evaluated before exposure and up to 2 weeks post-exposure. RESULTS: ABR thresholds were transiently elevated immediately after exposure but largely recovered by 1 day post-exposure. In contrast, ABR wave I amplitudes significantly increased after threshold recovery across multiple test frequencies. Ribbon-associated puncta in both inner and outer hair cell regions exhibited biphasic temporal changes, with an initial decrease immediately after exposure followed by an increase at 1 day post-exposure. The ribbon-associated punctal area also increased after exposure and remained elevated at later post-exposure time points. No significant loss of hair cells or spiral ganglion neurons was observed. Exploratory genomic analysis suggested enrichment of pathways related to metabolic defense and cellular stress responses. CONCLUSIONS: Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of peripheral auditory nerve output without overt cellular degeneration. These findings support a model in which early cochlear responses to acoustic perturbation include adaptive synaptic plasticity and gain regulation, extending current concepts of noise-induced cochlear change beyond irreversible synaptic loss.

Animals↗

PubMed2026

Differential contributions of mt-Tr and Cs variants to developmental cochlear defects and mitochondrial dysfunction in A/J mice.

A/J mice exhibit early-onset hearing loss linked to Cdh23, mitochondrial tRNA-Arg (mt-Tr), and citrate synthase (Cs) variants. Although developmental cochlear defects have been identified in juvenile A/J mice, the hierarchical contributions of mt-Tr versus Cs remain unclear. Using reciprocal intercross-derived strains to decouple mitochondrial haplotypes from nuclear factors, we demonstrate that the mitochondrial background is the primary determinant of auditory dysfunction. Mice with A/J mtDNA (AXB strains) displayed significantly higher ABR thresholds, accelerated hair cell attrition, and severe stereocilia dysmorphology compared to those with B6 mtDNA (BXA strains), occurring largely independently of the Cs genotype. While the Cs mutation exacerbated hearing loss, its impact was secondary to that of the dominant mitochondrial background. Systemic behavioral assessments and mitochondrial assays confirmed that A/J mitochondria exert a more profound metabolic impact than the Cs mutation. Our findings establish that the mitochondrial genomic background, with the mt-Tr locus as a prominent candidate variant, serves as the principal driver of developmental cochlear defects and early-onset hearing loss in A/J mice, while the nuclear Cs mutation acts as a synergistic modifier. This study underscores the critical role of mitonuclear crosstalk in inner ear maturation and provides new insights into the etiology of hereditary hearing loss.

Animals↗

PubMed2026

A translational framework for early-phase inner-ear gene therapy: clinical trial design, regulatory strategy, and ethical considerations.

PURPOSE OF REVIEW: Hereditary hearing loss has historically been approached as a diagnostic category rather than a therapeutically modifiable disease. Recent advances in molecular genetics, cochlear gene delivery, and first-in-human clinical trials are changing that. This review summarizes contemporary progress in the genetics of hearing loss, with emphasis on emerging gene-based therapies, clinical trial design, regulatory and ethical considerations, and practical implications for otolaryngologists as biologic treatment enters clinical practice. RECENT FINDINGS: Early clinical trials targeting OTOF -related DFNB9 deafness have demonstrated satisfactory safety profiles and meaningful auditory recovery, establishing the first proof-of-concept for cochlear gene therapy in humans, culminating in the April 2026 FDA approval of Otarmeni. Genetic diagnoses are increasingly informing prognosis, cochlear implant counseling, and therapeutic candidacy. Preclinical research continues to expand toward recessive, dominant, and syndromic hearing loss using gene replacement, antisense, RNA interference, and genome-editing strategies. Substantial challenges remain, including heterogeneous outcome measures, uncertain long-term efficacy, regulatory complexity, and inequitable global access. SUMMARY: The genetics of hearing loss is transitioning from a diagnostic modality to an interventional one. Widespread clinical impact will require advances in vector engineering, equitable implementation, multidisciplinary counseling, and integration with established rehabilitation pathways. For otolaryngologists, genetic literacy is becoming essential to contemporary hearing care.

Humans↗

PubMed2026

Can ChatGPT Replace Human Clinical Coders? A Comparative Study in Otology Billing.

OBJECTIVE: Evaluate the utility of the large language model (LLM), ChatGPT, for the analysis of operative notes and the generation of Current Procedural Terminology (CPT) codes in comparison to human clinical coders. STUDY DESIGN: CPT billing codes assigned by ChatGPT were compared to existing billing data. Otology practice within a tertiary academic center. METHODS: About 191 operative notes from a single surgeon (9/2022-10/2023) were analyzed. ChatGPT-3.5 and 4 models were prompted for CPT codes based on operative notes. Assessment included determining exact and partial match rates, sensitivity and specificity for targeted procedures, and work Relative Value Units (wRVU) differences between ChatGPT-generated and human-assigned codes. RESULTS: ChatGPT-3.5 achieved exact matches in 22% of cases and partial matches in 32%, while ChatGPT-4 achieved 14% exact and 33% partial matches. When cochlear implantation (CI) was excluded, performance dropped significantly. For CI, ChatGPT-3.5 demonstrated a sensitivity of 94% and specificity of 90%, while ChatGPT-4 showed a sensitivity of 96% and specificity of 92%. In contrast, performance on cartilage grafting was poor, with sensitivities of 4.2% for ChatGPT-3.5 and 0% for ChatGPT-4. ChatGPT-3.5 and 4 showed moderate CPT code matching accuracy among themselves, with slight agreement to human coders. Both models tended to underbill for wRVUs compared to human coders, with significant differences in the values generated. CONCLUSION: This study assessed ChatGPT's effectiveness in automating CPT code assignment for otologic surgeries. While the models achieved high sensitivity values for assigning codes related to cochlear implantation, both models struggled with complex cases, failed to apply modifiers, and often assigned fewer wRVUs. The findings highlight ChatGPT's potential in medical billing but indicate a need for further refinement.

Humans↗

PubMed2026

Utility of hearing aid use on neurocognitive functions and auditory processing: A systematic review.

PURPOSE: Hearing loss not only affects the peripheral auditory system but also leads to changes in central auditory pathways and neurocognitive skills. The use of hearing aids has shown potential benefits in mitigating the adverse effects of hearing loss. Earlier literature showed various studies assessing the impact of hearing aid use on cognitive functions and auditory processing, a comprehensive review of the existing literature is warranted. Existing literature showed heterogeneous outcomes among studies investigated the effect of Hearing aid use in combating the adverse effects of hearing loss on neurocognitive functions and auditory processing. METHOD: Databases including PubMed, SciELO, Cochrane Library, PsycINFO, Web of Science, and Index Copernicus were searched (2005-2025) using English keywords on hearing aid effects on neurocognition and auditory processing in individuals with hearing loss. Studies on effect of hearing aid use on neurocognition and auditory processing were included, while those involving cochlear implant users or other neurological disorders unrelated to hearing loss were excluded. Titles, authors and publication years were examined, and duplicates were removed. RESULTS: Total of 61 research papers were found on specific area and were included in the present review. Findings of these 61 articles have been analysed and are reported in this article. The outcome of the present study showed usefulness of hearing aid use on neurocognitive functions and auditory processing. CONCLUSION: The present literature review emphasized the importance of early rehabilitation through hearing aid use to alleviate the adverse effects of hearing loss on neurocognitive function and auditory processing.

Humans↗

PubMed2026

Re-evaluating pediatric laryngoscope blade size recommendations: Comparable intubation performance across blade sizes in pediatric manikin models.

BACKGROUND: Pediatric airway management traditionally emphasizes strict adherence to age-based laryngoscope blade size recommendations, despite limited empirical validation. OBJECTIVES: To evaluate whether intubation performance varies across a range of blade sizes, and whether a Macintosh 2 blade performs comparably across multiple pediatric age groups in a simulation setting. METHODS: We conducted a randomized crossover simulation study using three pediatric airway manikins (neonate, infant, and child age groups). Emergency medicine residents and faculty physicians performed intubations using multiple laryngoscope blade types and sizes, including standard and nonstandard options. Primary outcomes were intubation time and first-attempt success. Secondary outcomes included complications and operator-rated ease of glottic view and tube passage. Between-blade differences were estimated with 95% confidence intervals. RESULTS: Across manikin sizes and blade types, intubation times were short and first-attempt success rates exceeded 98% in most conditions. Performance remained consistent even with blade sizes outside conventional age-based recommendations. Between-blade differences in intubation time were small, and complication rates were low across conditions. The Macintosh 2 blade performed comparably across all manikin sizes, with similar intubation times, high success rates, and favorable ease ratings. CONCLUSIONS: Intubation performance in pediatric manikin models was similar across a wide range of blade sizes. These hypothesis-generating findings warrant prospective clinical evaluation of simplified blade selection strategies for pediatric intubation.

Manikins↗

PubMed2026

Cis-regulatory variation in the MdCKX6 promoter is associated with allele-specific expression and fruit size in apple.

Fruit size is a key determinant of apple fruit quality and market value and is strongly influenced by phytohormone-regulated cell proliferation and expansion during early fruit development. Cytokinin oxidase/dehydrogenase (CKX) enzymes regulate cytokinin homeostasis by irreversibly degrading active cytokinins, but the contribution of natural variation in CKX genes to fruit size remains poorly understood. Here, we identified MdCKX6 as a candidate regulator of fruit growth in apple (Malus domestica). MdCKX6 exhibited pronounced allele-specific expression during fruit development in the cultivar 'Royal Gala'. Sequence analysis identified a promoter SNP associated with differential promoter activity and allele-specific expression. Genotyping of diverse apple cultivars and wild Malus accessions revealed a significant association between MdCKX6 promoter genotype and fruit size. Cultivars carrying low-expression alleles produced larger fruits, whereas high-expression alleles were associated with smaller fruits. To investigate gene function, MdCKX6 was overexpressed in tomato, resulting in reduced fruit size. Histological analyses of the transgenic tomato fruit revealed smaller pericarp cells. Transcriptome analysis of transgenic fruits revealed widespread changes in genes associated with cell-cycle regulation, cell wall modification, hormone-related processes, and transcriptional regulation. Together, these results identify MdCKX6 as a potential negative regulator of apple fruit growth and reveal an association between cis-regulatory variants, gene expression, and fruit size. This study provides new insights into the role of cytokinin metabolism in fruit development and highlights regulatory variation in MdCKX6 as a potential target for apple breeding.

Malus↗

PubMed2026

Divergent trajectories of genome architecture and chromosome evolution in ferns and angiosperms.

Ferns and angiosperms represent the two largest vascular plant lineages but exhibit striking genomic and ecological contrasts. We investigated whether differences in genome size, chromosome architecture, GC content, and stomatal traits reveal divergent evolutionary trajectories between these lineages. We assembled the most comprehensive dataset to date, integrating genome size, chromosome number and size, GC content, and stomatal traits for over 1100 fern species and compared it with an extensive angiosperm dataset. Ferns exhibited markedly lower variability and c. 16-fold slower rates of chromosome size evolution than angiosperms. A persistent positive relationship between genome size and chromosome number in ferns suggests limited cytological post-polyploid diploidization. While ferns generally possess larger stomata, this difference disappears after accounting for genome size, indicating that nucleotypic constraints, rather than lineage-specific physiology, dictate stomatal dimensions. Both groups share a unimodal GC-genome size relationship peaking at c. 14 Gbp. Larger fern chromosomes imply lower genome-wide recombination rates, potentially limiting genetic reshuffling and adaptive potential. Our results highlight fundamentally divergent evolutionary trajectories, likely shaped by meiotic symmetry in ferns and meiotic asymmetry, possibly centromere drive, and post-polyploid diploidization in angiosperms, defining the functional and genomic landscapes of these lineages across deep evolutionary timescales.

Genome, Plant↗

PubMed2026

Weight Loss without Food Intake Suppression through Size-Dependent Retention of Anti-Inflammatory Nanomedicines.

Obesity is a risk factor for high-mortality health conditions, including cardiovascular diseases and type 2 diabetes, which makes the advancement of efficacious and safe weight loss therapies a high priority in pharmacology. The causal link between obesity and its comorbid conditions is believed to be a chronic state of inflammation originating within adipose tissue, with macrophages playing central roles, an axis that is not targeted directly by current therapies. Here, we use nanocarriers to deliver an anti-inflammatory glucocorticoid receptor agonist to adipose tissue macrophages and report the impact of size on therapeutic effect. Three dextran nanocarriers between 4-30 nm in hydrodynamic diameter released molecular drug cargo at equivalent rates and exhibited similar biological potency in vitro. In vivo in a mouse model of obesity, body weight and body fat were reduced in a size-dependent manner after 2-4 weeks of treatment. Unlike current clinical pharmacotherapies for weight loss, these body composition changes were not associated with changes in food intake. Greater retention of larger dextran nanocarriers in visceral adipose tissue appears to elicit a local change to promote browning by increasing mitochondrial abundance and lipid droplet fragmentation. Further development of this platform may result in a safe and potent modulator of adipose tissue in the state of obesity without direct action on nutrient intake to address malnutrition and lean body mass deficiencies observed with current weight loss pharmacotherapies.

Animals↗

PubMed2026

Skeletal Muscles Do Not Compete for Growth: Activating Additional Muscle Mass Does Not Compromise Changes in Muscle Size.

Kataoka, R, Yamada, Y, Hammert, WB, Sallberg, RW, Kang, A, Song, JS, Kassiano, W, Metcalf, EE, and Loenneke, JP. Skeletal muscles do not compete for growth: Activating additional muscle mass does not compromise changes in muscle size. J Strength Cond Res 40(9): 1043-1049, 2026-This study investigated whether the magnitude of muscle size and strength differed based on the amount of muscle recruited during training sessions. One hundred five untrained individuals were randomly assigned to 1 of 3 groups: low-load unilateral elbow flexion exercise (a) to failure (LL-Failure, n = 36), (b) to failure and low-load knee extension exercise to failure (LL-Failure + Legs, n = 33), or (c) a time-matched nonexercise control (CON, n = 36). Training groups completed 18 supervised sessions over 6 weeks (2 sets at 30% 1 repetition maximum [1RM] to failure). LL-Failure + Legs group performed 4 additional sets of knee extension exercise in each leg (20-30 RM). Muscle thickness on the anterior upper arm (60 and 70% sites) and elbow flexor 1RM strength of the trained arm were measured at pretesting and posttesting. Changes were compared using the ANCOVA function of Bayes Factors for Informative Hypotheses (prevalues as the covariate). Specific hypotheses were evaluated by comparing Bayes factors and the posterior probabilities between models. Six weeks of training led to increases in muscle size and strength. However, performing additional leg exercise did not attenuate the muscle growth in the anterior upper arm (0.19 cm) compared with performing only arm exercise to failure (0.18 cm). Changes in 1RM strength also did not differ between training groups (0.32 and 0.25 kg for LL-Failure and LL-Failure + Legs, respectively). Overall, there was no evidence for competition of adaptations in muscle size and strength under uncontrolled nutritional conditions. Whether greater training volume or limited nutrient intake induces a competition for resources warrants further investigation.

Humans↗

PubMed2026

Understanding and Usefulness of Effect Size and Certainty of Evidence: A Cross-Sectional Survey of Evidence-Based Practice Competencies Among US Registered Dietitians.

INTRODUCTION: Understanding of absolute and relative effect estimates, and determining effect size and certainty of evidence corresponding to effect estimates, represent fundamental evidence-based practice competencies that promote informed clinical decision-making. While research has been conducted in the medical profession, based on our literature review there is no published research on these competencies in the nutrition and dietetics profession. METHODS: Among registered dietitians, our main objectives were to assess (1) their understanding and perceived usefulness of three absolute and two relative effect estimate approaches to determine effect size, (2) their perceived usefulness of certainty of evidence, and (3) factors influencing their understanding and perceived usefulness. We conducted a web-based, cross-sectional survey by recruiting dietitians from the Academy of Nutrition and Dietetics (United States). Participants received effect estimates based on hypothetical dietary interventions vs. usual diet for reducing myocardial infarction risk. RESULTS: Of the 11,050 dietitians who received the survey link, 210 participated, and only completers (n = 114) were included in our analysis. Participants demonstrated a similar understanding of the relative (27.6%) and absolute (27.5%) effect estimates, with Risk Difference being the best understood approach and Number Needed to Treat being the least (30.7% vs. 24.6% correct responses). While perceived usefulness scores were similar between five approaches, they were highest when data was presented as Relative Risk [mean (SD): 4.82 (1.50)]. Dietitians rated the usefulness of certainty of evidence favorably [mean (SD): 5.07 (1.83), on a 7-point scale], and no factors were associated with correct understanding. CONCLUSION: Dietitians may have limited understanding of effect size thresholds presented in our survey, a finding mostly consistent with surveys of other health professionals. To optimize informed decision-making between dietitians and clients, dietetic programs and continuing education platforms should consider additional training on effect estimate approaches (relative and absolute), and determining effect sizes and certainty of evidence for effect estimates.

Clinical nutrition↗

PubMed2026

Trade-offs in avian parental care: a review of theory and meta-analysis of brood size manipulations.

The selective forces shaping parental care have been studied for over 50 years. While theoretical and experimental work has yielded qualitative progress, the large body of empirical work testing predictions about parental investment based on life-history trade-offs has yet to be synthesized. We first provide an overview of the core life-history theory exploring how selection might shape parental care. We then conduct a systematic review and meta-analysis on studies that experimentally manipulated brood size in birds, a widely used experimental approach to manipulate parental investment. We extracted 313 estimates from 62 studies representing 31 species of birds from 19 different families and tested key predictions on trade-offs in parental care derived from theory. Our analysis provides strong support for some predictions about life-history trade-offs in parental care, but weak or equivocal support for others. Specifically, we found that overall, avian parents respond to brood size manipulations as predicted by life-history theory: they increased care in response to brood enlargement, and decreased care in response to brood reductions. Furthermore, for the same relative manipulation size, responses to brood reductions were greater than responses to brood enlargements. This finding is consistent with predictions derived from life-history theory based on some types of non-linear utility curves. However, many predictions derived from theory are not well supported by our comparative analysis. Species' life-history traits such as clutch size (a measure of current reproduction), adult survival, and broods per year (two measures of future reproduction), explained little, if any, among-species variation in response to brood size manipulations. Several factors may explain this. We highlight that brood size manipulations may affect more than just perception of the value of current reproduction, such as altering parents' perception of predation risk. Importantly, these unintended consequences could lead to asymmetric responses like those we observed. Other common experimental approaches - such as hormone manipulations, altering a partner's effort, and food supplementation - often affect multiple traits or fitness components simultaneously, or may involve cues that poorly match the evolved mechanisms guiding parental behaviour. Our review of both theory and experimental approaches suggests that there are multiple opportunities for more precise experiments. We offer several recommendations for effective designs. One is improved understanding of the biology underlying the functions relating to costs and benefits, with careful consideration of not only how the manipulation will affect only one of those, but also the mechanisms that might alter how parents perceive the manipulation. We also emphasize general principles, such as assessing alternative hypotheses and devising multiple independent tests. Armed with these recommendations, we believe there are new opportunities to increase the strength of inference achieved from studies aimed at understanding the trade-offs affecting the evolution of parental care.

Animals↗

PubMed2026

Exposure to size-specific particulate matter accelerates DNA methylation aging in people with HIV.

BACKGROUND: People with HIV (PWH) face accelerated aging and increased health risks, with DNA methylation age (DNAmAge) as a critical senescence biomarker. Particulate matter is linked to DNAmAge acceleration (DNAmAA) in general population, but its impact in PWH remains unstudied. METHODS: Thirty-two PWH from Wuhan, China, were enrolled in a prospective panel study with follow-up, and each participant underwent at least two repeated measurements during the study period. Portable air quality monitor measured PM 1 , PM 2.5 , and PM 10 exposures 72 h preblood sampling. We analyzed genome-wide DNA methylation in peripheral blood and calculated six AA metrics. Linear mixed-effects and weighted quantile sum regression models evaluated associations between particulate matter exposure and DNAmAA. RESULTS: Significant associations between particulate matter exposure and DNAmAA were observed at various lag windows. For every 10 μg/m 3 increase in 24-h average PM 2.5 , Hannum DNAmAA, Pheno DNAmAA, Grim DNAmAA, SkinBlood DNAmAA, and Elastic DNAmAA increased by 0.266 years [95% confidence interval (CI): 0.035-0.480], 0.421 years (95% CI: 0.032-0.701), 0.336 years (95% CI: 0.073-0.546), 0.295 years (95% CI: 0.021-0.495), and 0.254 years (95% CI: 0.034-0.445), respectively. PM 10 contributed most substantially to the cumulative PM effect on epigenetic AA in the lag0-24 h window. CONCLUSION: Short-term particulate matter exposure, particularly PM 10 , significantly accelerates epigenetic aging in PWH, highlighting the need to integrate air quality management into healthy aging strategies for this vulnerable population.

China↗