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PubMed2026

Ultra-high-frequency ECG quantifies residual electrical dyssynchrony during left bundle branch area pacing in patients with wide QRS: a paired within-patient study.

BACKGROUND: Left bundle branch area pacing (LBBAP) may restore a more physiological pattern of ventricular activation in patients with conduction delay; however, QRS narrowing alone may incompletely characterize electrical resynchronization. Ultra-high-frequency ECG (UHF-ECG) provides quantitative markers of ventricular activation timing and dyssynchrony. OBJECTIVE: To quantify paired OFF-to-ON changes in conventional ECG and UHF-ECG metrics during LBBAP in patients with baseline wide QRS and to assess the relationship between paced R-wave peak time (RWPT) and residual UHF-ECG dyssynchrony. METHODS: In this prospective single-center paired study, 21 patients with bradycardia and baseline wide QRS underwent standard ECG and UHF-ECG assessment during intrinsic rhythm (pacing OFF) and during LBBAP (pacing ON). Endpoints included QRS duration, signed VED16, absolute VED16 (|VED16|), mean ventricular delay (meanVD), and a clinically interpretable distance-to-normal metric defined as dist = max(|VED16|-20, 0). Paired changes were summarized as medians with bootstrap 95% confidence intervals and tested using the Wilcoxon signed-rank test. Associations between paced RWPT and residual dyssynchrony during pacing were evaluated using Pearson and Spearman correlation coefficients. RESULTS: LBBAP significantly narrowed QRS duration from 136.8 [130.2-153.6] ms during intrinsic rhythm to 116.0 [107.8-125.6] ms during pacing (median Δ -21.0 ms; 95% CI -33.9 to -18.6; p < 0.001). Signed VED16 did not change significantly (median Δ 0.4 ms; p = 1.000), consistent with the mixed conduction-phenotype composition of the cohort. In contrast, severity-oriented UHF-ECG endpoints improved: |VED16| decreased numerically (median Δ -5.2 ms; p = 0.070), whereas dist decreased significantly (median Δ -0.7 ms; 95% CI -14.4 to 0.0; p = 0.015). The proportion of patients within the normal dyssynchrony band (|VED16| ≤ 20 ms) increased from 7/21 (33.3%) to 12/21 (57.1%). Median paced RWPT was 66.6 [58.6-74.6] ms, and shorter RWPT correlated with lower residual |VED16| during pacing (Pearson r = -0.45, p = 0.038). CONCLUSIONS: In patients with baseline wide QRS, LBBAP produces marked QRS narrowing, whereas UHF-ECG provides complementary quantification of residual electrical dyssynchrony. Severity-oriented UHF-ECG endpoints, particularly a distance-to-normal metric, may offer an interpretable mechanistic framework beyond conventional ECG alone. Shorter paced RWPT was associated with lower residual dyssynchrony during pacing, supporting physiological coherence between procedural and high-resolution electrocardiographic markers.

Humans↗

PubMed2026

Conduction System Pacing Versus Right Ventricular Pacing in Patients With Atrioventricular Block and Anticipated High Pacing Burden.

Right ventricular pacing (RVP) in patients with atrioventricular (AV) block and high anticipated pacing burden is associated with pacing-induced cardiomyopathy (PICM) in approximately 12% to 20% of patients, whereas conduction system pacing (CSP) preserves more physiologic ventricular activation and may mitigate these consequences; the totality of contemporary randomized evidence has not been systematically pooled. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing CSP with RVP in patients with AV block or anticipated high ventricular pacing burden and a minimum 6-month follow-up, with co-primary outcomes of PICM incidence and change in left ventricular ejection fraction (ΔLVEF) and secondary outcomes of heart failure hospitalization (HFH), all-cause mortality, composite clinical endpoint, and paced QRS duration (PROSPERO CRD420261400227); random-effects meta-analysis used DerSimonian-Laird estimation. Five RCTs (LBBP-FAVOUR, CSPACE, Prague CSP, PACE-HF, STAY; N = 806) met inclusion criteria. CSP significantly reduced PICM (hazard ratio [HR] 0.30, 95% confidence interval [CI] 0.18 to 0.48; p <0.001; I² = 0%; k = 4), was associated with greater LVEF preservation (pooled mean difference [MD] +4.41%, 95% CI +1.82 to +6.99; p = 0.001; I² = 87%; k = 5), and reduced HFH (HR 0.24, 95% CI 0.12 to 0.48; p <0.001; I² = 0%; k = 5). CSP shortened paced QRS duration (MD -27.5 ms, 95% CI -32.6 to -22.5; p <0.001; k = 5). All-cause mortality was numerically lower with CSP but did not reach significance (HR 0.57, 95% CI 0.29 to 1.12; p = 0.10; k = 4). In a prespecified sensitivity analysis restricting to multicenter trials with N ≥ 150, all findings were concordant with the primary analysis. In conclusion, CSP substantially reduces PICM, preserves LVEF, and reduces HFH compared with RVP in patients with AV block and anticipated high pacing burden, supporting its consideration as the preferred pacing strategy in appropriately selected patients.

Humans↗

PubMed2026

Fundamentals of pacemakers ECG interpretation - part 2.

BACKGROUND: Modern pacemakers incorporate arrhythmia-response algorithms, ventricular pacing minimization protocols, and safety mechanisms that generate ECG patterns indistinguishable from pathological AV block, sensing malfunction, or device-mediated tachycardia. Failure to recognize these algorithm-driven signatures leads to unnecessary interventions, misdiagnosis, and inappropriate device reprogramming. This manuscript is the second in a two-part series on pacemaker ECG interpretation. METHODS: We conducted a narrative review of peer-reviewed literature and device-specific documentation on algorithm-driven ECG behavior, synthesizing evidence across arrhythmia recognition, upper rate physiology, ventricular pacing minimization, mode switching, safety mechanisms, and hysteresis algorithms. RESULTS: Pacemaker-mediated tachycardia produces regular paced wide-complex tachycardia locked at the upper tracking rate, initiated by any event with retrograde VA conduction. Ventricular tachycardia is identified by QRS morphology diverging from the known paced pattern, absent pacing spikes, and AV dissociation. Upper rate Wenckebach behavior mimics Mobitz type I AV block; 2:1 upper rate response mimics second-degree AV block. Ventricular pacing minimization algorithms produce isolated nonconducted P waves and prolonged AV intervals that simulate pathological conduction disease. Mode switching causes abrupt rate drops misidentified as output failure. Ventricular safety pacing generates a conspicuously short, fixed AV interval. Three discrete pacing artifacts reflect AV-sequential cardiac resynchronization therapy (CRT), ventricular safety pacing in CRT, or His-bundle pacing with backup RV output. Rate and AV hysteresis produce pauses and wandering AV intervals mimicking oversensing or Wenckebach periodicity. CONCLUSIONS: Recognizing algorithm-driven ECG patterns requires knowledge of device timing intervals and refractory periods, which lets clinicians distinguish programmed behavior from true malfunction or cardiac arrhythmia.

Humans↗

PubMed2026

Feasibility and efficacy of left bundle branch area pacing guided by modified chest lead 1.

BACKGROUND: Left bundle branch area pacing (LBBAP) typically requires 12‑lead electrocardiogram (ECG) measurements using an electrophysiology (EP) recording system. However, a simplified approach using modified chest lead 1 (MCL1) is potentially feasible. This study aimed to compare the success rate and pacing outcomes of LBBAP guided by MCL1 with those guided by the 12‑lead ECG using an EP recording system. METHODS: This retrospective, single-center study included patients with preserved left ventricular ejection fraction who underwent LBBAP for bradyarrhythmia. LBBAP was either guided by 12‑lead ECG using an EP recording system or by MCL1. In the MCL1 group, a follow-up examination with a 12‑lead ECG using an EP recording system was conducted within one week postoperatively. RESULTS: A total of 65 patients underwent LBBAP (EP recording system group: n = 35; MCL1 group: n = 30). The overall success rate of LBBAP was 84.6%, with no significant difference between groups (88.5% vs. 80.0%, p = 0.49). No significant differences were observed in the paced QRS duration (140.4 ± 8.0 vs. 141.9 ± 13.1 ms, p = 0.54), V6-V1 interpeak interval (39.7 ± 16.5 vs. 38.3 ± 15.6 ms, p = 0.79), or V6 R-wave peak time (69.8 ± 12.3 vs. 71.5 ± 12.1 ms, p = 0.68). CONCLUSIONS: MCL1-guided LBBAP was feasible and achieved a high success rate, with outcomes comparable to those of conventional EP recording system-guided implantation. This simplified approach may reduce procedural complexity and may allow LBBAP implantation without the routine use of an EP recording system.

Humans↗

PubMed2026

Electrocardiographic correlates of pacing induced cardiomyopathy and response to cardiac resynchronization therapy.

BACKGROUND: Chronic right ventricular (RV) pacing (RVP) causes pacing-induced cardiomyopathy (PICM) in only a small number of patients. We evaluated ECG correlates of (i) PICM and (ii) response to cardiac resynchronization therapy (CRT) upgrade. METHODS: We conducted a retrospective case-control study by including all CRT upgrades for PICM (LVEF <50%) at our center between 2014 and 2018. Controls were patients with ≥5 ECGs all demonstrating RVP over ≥2 years and all echocardiographic LVEF ≥50%. Root-summed-squared (3D) ECG was obtained from reconstructed vectorcardiographic X-Y-Z leads. Predictors of PICM and CRT response were assessed as area under ROC curve (AUC) for pre-CRT and Δ (post-CRT - pre-CRT) ECG intervals and QRS voltage-time-integrals (VTI). RESULTS: We included 104 patients with CRT upgrade for PICM (age 73.7 ± 10.5 years, female 29.1%, QRS duration 167.8 ± 25.2 ms, LVEF 28.8 ± 8.0%, ΔLVEF 13.8 ± 10.3%) and 178 controls without PICM (age 73.2 ± 14.9 years, female 52.8%, QRS duration 144.0 ± 20.9 ms, LVEF 56.7 ± 5.2%). PICM was best identified by VTIQRS-3D (AUC 0.851; VTIQRS-3D ≥ 80 μVs sensitivity 87.5%, specificity 63.5%), VTIQRS-Y (0.846), and QRS duration (0.775). CRT response (LVEF increase ≥10% at 3-12 months) occurred in 73/104 (70.2%) patients. Lack of CRT response was best predicted by longer pre-CRT QRS duration (AUC 0.640; QRS duration ≥180 ms sensitivity 45.2%, specificity 83.6%), and less ΔVTIQRS-3D (0.609) and ΔVTIQRS-X (0.608). CONCLUSION: In patients with chronic RVP, VTIQRS-3D ≥ 80 μVs can be used as a screening test for echocardiographic confirmation of PICM. RV-paced QRS duration >180 ms, on the other hand, identifies those who may not respond to CRT upgrade.

Humans↗

PubMed2026

Single-slice Functional Lung MRI During Metronome-Paced Tachypnea Detects Changes in Regional Ventilation Dynamics After a Single Dose of Dual Bronchodilator Treatment in COPD.

Dual long-acting bronchodilators are a standard treatment in chronic obstructive pulmonary disease (COPD), aimed at alleviating dyspnea, improving exercise tolerance, and preventing exacerbations. Metronome-paced tachypnea (MPT) offers a feasible alternative to exercise testing for the evaluation of dynamic hyperinflation (DH) in COPD. Because MPT can be performed during MRI, its combination with single-slice phase-resolved functional lung (PREFUL) MRI provides a promising approach to investigate changes in regional ventilation dynamics induced by DH. This approach was evaluated in a randomized, investigator-blinded, placebo-controlled, single-dose (SD) crossover trial with a two-week extension of once daily dual bronchodilator medication, in which patients with stable COPD underwent PREFUL MRI during resting tidal breathing (RTB) and during MPT. During RTB, no significant improvements in MRI-derived parameters were observed after SD treatment compared with placebo. During MPT, however, regional ventilation, flow-volume loop correlation, its defect percentage, and end-expiratory lung area improved significantly after SD treatment compared to the placebo scan (all p < 0.02). After multi-dose treatment, five out of six measured parameters improved during MPT, when compared to the baseline scan without bronchodilator treatment (all p < 0.03). In contrast to RTB, PREFUL MRI during MPT was able to detect changes in COPD patients already after SD treatment. The combination of MPT and PREFUL MRI represents a promising method to evaluate the effects of dual bronchodilators on regional ventilation dynamics and hyperinflation.

Humans↗

PubMed2026

Teach-Back in Clinical Communication: A Systematic Review and Meta-analysis.

BACKGROUND: Teach-back has been identified as a high-quality clinical communication strategy. Our aim was to synthesize current literature on teach-back effectiveness. METHODS: We searched MEDLINE, Embase, and CINAHL Complete databases to identify relevant studies published between 2018 and 2026. We also included pre-2018 studies identified in prior systematic reviews. Studies were eligible for inclusion if they involved adult patients and/or care partners, delivered teach-back in a single encounter, had a comparator group, and reported proximal/intermediate patient outcomes (as defined in our conceptual model). Two independent investigators screened each citation at the title/abstract and full-text levels and assessed risk of bias. Study characteristics and results were extracted. When meta-analysis was performed, we used standardized mean differences (SMD) to estimate summary effects. We assessed certainty of evidence (COE) using Grading of Recommendations Assessment, Development and Evaluation (GRADE) domains. RESULTS: Our systematic review included 18 randomized controlled trials (RCTs) involving 1985 participants. Across 9 RCTs assessing knowledge acquisition, conceptual inconsistencies precluded meta-analysis. Overall, there was no clear pattern of the effect of teach-back on knowledge (very low COE). In a meta-analysis of 5 RCTs assessing self-efficacy (416 participants), we found that teach-back interventions led to a large increase in self-efficacy relative to usual care (SMD = 2.40; 95%CI 0.37-4.44) (very low COE). In a meta-analysis of 7 RCTs assessing adherence to health behaviors (571 participants), teach-back interventions led to a large increase in adherence (SMD = 1.04; 95%CI 0.45-1.64) (low COE). Meta-analyses for both self-efficacy and adherence had large confidence intervals that ranged from small to large effect sizes and had substantial heterogeneity. DISCUSSION: In this systematic review and meta-analysis, we did not identify a clear benefit of teach-back on knowledge acquisition but did find evidence that teach-back improves self-efficacy and self-reported, short-term adherence to health behaviors.

clinical communication↗

PubMed2026

Temporal redistribution of control reveals age-related differences in task switching at the level of preparation.

Task-switching studies often report minimal age-related differences in switch costs, leading to the conclusion that switching-related control processes are relatively preserved in aging. However, this conclusion is based on paradigms that confound preparatory and execution processes. This study examined whether age-related differences in semantic task-set reconfiguration may be underestimated due to this confound. In Experiment 1 (36 young and 30 older adults), participants performed an externally paced task-switching paradigm without control over preparation. In Experiment 2 (28 young and 28 older adults), a self-paced paradigm allowed participants to initiate stimulus onset, enabling measurement of preparation time. Across both experiments, reaction time (RT) and error rate (ER) showed reliable age effects but no interactions between age and condition, whereas switching-related condition effects varied across measures and experiments. The expression of switching-related costs differed across measures and task structures. Local switch costs were expressed in ER in Experiment 1 but in RT in Experiment 2. Global switch costs (all-switch vs. all-repeat) were observed in execution measures only in Experiment 1. In Experiment 2, preparation time showed reliable mixing, local, and global switching effects, with age-related amplification emerging specifically for global switching. These findings indicate that switching-related costs are redistributed across processing stages and behavioral measures. The results suggest that age-related modulation of semantic task-set reconfiguration may emerge more clearly during preparation than task execution, particularly under continuous switching demands. Preparation time is interpreted cautiously as reflecting participant-regulated preparatory processes rather than a pure measure of preparation efficiency.

Humans↗

PubMed2026

New Evidence in Heart Failure: 2026 Update.

Heart failure (HF) remains a major cause of morbidity, mortality, impaired quality of life and healthcare expenditure worldwide. The global burden of HF continues to increase due to population aging, improved survival, and the growing prevalence of cardiovascular, renal, and metabolic comorbidities. Simultaneously, the pace of scientific progress in HF has accelerated considerably. Recent advances have refined our understanding of HF epidemiology, prognosis, and disease trajectories, including emerging concepts of HF improvement, remission, and recovery. The Second Universal Definition of HF has also updated the classification framework, moving beyond the traditional ejection fraction-based categories. HF is now broadly classified into two major phenotypes: heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). Novel mechanistic insights highlight the role of inflammation, immune activation, metabolic dysfunction, mitochondrial biology, and multisystem interactions in HF progression. There has also been significant progress in the characterization and management of major comorbidities, including chronic kidney disease (CKD), diabetes, obesity, atrial fibrillation (AF), pulmonary hypertension, frailty, malnutrition, and cancer. Diagnostic innovations include novel biomarkers, multi-omics technologies, artificial intelligence-based approaches, advanced imaging techniques, congestion assessment tools, and emerging digital health solutions. Important advances have occurred in specific HF aetiologies, including cardiomyopathies, cardiac amyloidosis (CA), myocarditis, arrhythmia-induced cardiomyopathy (AiCM), and Chagas cardiomyopathy. Therapeutic developments continue to reshape HF management across the spectrum of left ventricular ejection fraction. Recent evidence has focused on optimization of guideline-directed medical therapy in HFrEF, expansion of evidence-based therapies in HFpEF, and growing roles for sodium-glucose cotransporter-2 inhibitors, finerenone, incretin-based therapies, and transcatheter valve interventions. Collectively, these advances support the transition from a predominantly phenotype-based approach towards a more personalized and biologically informed model of HF care, with the potential to further improve outcomes across the entire HF spectrum.

Journal Article↗

PubMed2026

Implementing Prolonged Exposure Therapy in a Community Substance Use Treatment Program: A Qualitative Study.

INTRODUCTION: Post-traumatic stress disorder (PTSD) commonly co-occurs with substance use disorders (SUD), yet few community-based SUD programs incorporate evidence-based trauma-focused. Prolonged exposure (PE), including its massed format (M-PE) with session frequency of 3-4 times per week, is a gold standard intervention for PTSD; however, concerns about client readiness, logistical demands and relapse risk have limited its adoption within SUD settings. This study examined staff perspectives on the feasibility and acceptability of integrating M-PE into a community-based SUD program. METHODS: Prior to launching a Hybrid Type 1 effectiveness-implementation trial (Project COMET), we conducted semi-structured virtual interviews with 15 community clinic staff: providers (n = 8), administrators (n = 2) and peer specialists (n = 5). Interviews were recorded, transcribed and analysed using a rapid qualitative analysis framework with matrix techniques to compare themes across roles. RESULTS: Four overarching themes captured staff perspectives on integrating M-PE: (Theme 1) Prior Knowledge and Experiences: Most staff were familiar with EMDR, while direct knowledge of PE/M-PE was limited. (Theme 2) Perceptions of M-PE: M-PE was widely viewed as a promising, structured intervention that fits the pacing and duration of SUD care. (Theme 3) Symptom Reduction and Client Impact: Staff anticipated improvements in PTSD and SUD symptoms through trauma-focused treatment. (Theme 4) Barriers and Constraints: Participants identified several potential implementation challenges, including logistical barriers and client readiness. DISCUSSION AND CONCLUSIONS: Findings suggest that staff generally viewed M-PE favourably but emphasised the importance of ensuring client readiness and organisational support. Enhancing feasibility and long-term sustainability may require expanded psychoeducation, targeted provider training and flexible delivery models. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06968832.

Adult↗

PubMed2026

Corrigendum to "Characteristics of the long non-coding RNA-mRNA regulatory network in American eel (Anguilla rostrata) during Vibrio harveyi infection" [Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics 59 (2026) 101871].

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Published Erratum↗

PubMed2026

Review: The African turquoise killifish as a model for the integrative physiology of vertebrate aging.

With increasing emphasis on extending healthy lifespan, aging research requires vertebrate models that permit efficient mechanistic investigation and intervention testing within practical time and cost constraints. The African turquoise killifish (Nothobranchius furzeri) has attracted growing attention because it combines an exceptionally short life cycle with an intact vertebrate physiological context and an expanding genetic toolkit, enabling relatively rapid evaluation of candidate aging interventions and mechanistic analysis across molecular, tissue, and organismal levels. This review assesses N. furzeri from an integrative-physiology perspective, focusing on germline-soma interactions, gut microbiota-host crosstalk, nutrient sensing and metabolic remodeling, temperature responsiveness, and AMPK-mTOR-linked programs. It also examines expanding genome-engineering and reporter approaches that support mechanistic and tissue-resolved investigation of these physiological processes. Building on recent reviews of killifish biology, disease modeling, regeneration, and the hallmarks of aging, we synthesize evidence across major intervention domains, distinguish established phenotypic effects from incompletely resolved mechanisms, and highlight functional endpoints, methodological standardization, and the appropriate interpretation of the model's translational relevance. Together, these features position N. furzeri as a strategically useful vertebrate platform for rapid mechanistic testing, intervention evaluation, and prioritization of aging-related pathways. Future progress will require improved methodological standardization, tissue-resolved causal studies, and question-driven cross-species validation where appropriate.

Animals↗

PubMed2026

Potential Links Between Physiological and Perceptual Strain in High Heat Stress.

The physiological strain index (PhSI) is widely used to quantify thermoregulatory and cardiovascular strain during heat stress. However, direct physiological measurements may not always be feasible in occupational or athletic settings. Therefore, this study aimed to examine the relationship and agreement between perceptual strain and integrated physiological strain indices during high heat stress. Ten healthy, physically active, non-heat-acclimated males (29 (7) yr; 1.79 (0.11) m; 77.4 (9.3) kg) completed two randomized crossover exercise trials in hot-dry (HD) and warm-humid (WH) environments with equivalent wet-bulb globe temperatures. Heart rate, rectal temperature, skin temperature, rating of perceived exertion, and thermal sensation were measured at baseline and every 15 minutes during 60 minutes of cycling. Physiological strain index (PhSI), adaptive physiological strain index (aPhSI), and perceptual strain index (PeSI) were calculated using validated equations. Repeated-measures correlation analyses demonstrated very strong associations between PeSI and both PhSI and aPhSI under HD (Rrm = 0.940-0.943) and WH (Rrm = 0.980-0.982; all p < 0.001). Receiver operating characteristic analyses demonstrated good-to-excellent discrimination of physiological strain by PeSI (AUC = 0.895-0.969). Mixed-effects analyses showed that higher PeSI values were associated with increased PhSI (β = 1.325, p < 0.001) and aPhSI (β = 1.459, p < 0.001). However, Bland-Altman analyses demonstrated relatively small mean biases (0.4-0.9 AU) but wide limits of agreement (-2.8 to 4.2 AU), indicating that PeSI and physiological strain indices are not interchangeable. These findings suggest that PeSI may serve as a practical adjunctive or screening indicator of physiological strain when direct physiological measurements are unavailable.

Humans↗

PubMed2026

Physiologic age modifies the association between visceral fat predominance and urinary calcium excretion in adults with nephrolithiasis.

Although adiposity is associated with kidney stone disease, the relationship between abdominal fat distribution and urinary calcium excretion remains unclear. We investigated whether the CT-derived visceral-to-subcutaneous fat ratio (VSR) was associated with 24-hour urinary calcium excretion and whether physiologic age modified this association. This retrospective cross-sectional study included 308 adults with nephrolithiasis who underwent preoperative CT, stone removal, and postoperative metabolic evaluation. Participants were stratified into prespecified younger (men aged < 50 years and premenopausal women) and older (men aged ≥ 50 years and postmenopausal women) physiologic-age groups. Multivariable linear regression assessed the association between VSR and urinary calcium excretion and its modification by physiologic age. Results showed that VSR was not associated with urinary calcium excretion in the overall cohort, but its association differed significantly by physiologic age (P for interaction < 0.001). Among younger participants, each 1-unit higher VSR was associated with 2.07 mmol/day greater urinary calcium excretion (95% CI, 1.23-2.90), whereas no significant association was observed in the older group. These findings suggest that the metabolic relevance of visceral fat predominance differs by physiologic age, with a significant association observed only in younger adults. Prospective studies are needed to confirm these findings and determine their clinical implications.

Humans↗

PubMed2026

Ancient DNA and Human Physiology.

Ancient DNA (aDNA) enables the reconstruction of chronologically sampled genomes from ancient humans, animals, plants, pathogens, and microorganisms, as well as environmental DNA, providing a record of biological changes through time. Improvements in short and degraded DNA extraction methods and low-cost sequencing now enable the generation of broad, cross-regional datasets that expand evolutionary analyses from past population demography to biological mechanisms. By tracking temporal shifts of allele frequencies, integrating functional genomics resources (e.g., gene expression, chromatin structure variation), modeling population demography to separate selection from genetic drift, and aligning genetic changes with archaeological, cultural, and climatic data, aDNA has the potential to link sequence variation to physiological function within their temporal and environmental contexts. In this review, we summarize illustrative case studies from aDNA research spanning complex traits, dietary adaptations, and responses to pathogens and other environmental changes, showing how human biology has evolved under multiple selective pressures through time. These dated signals help triage experimental work and expose mechanisms that are rare or absent in living cohorts. Although some challenges remain, such as geographic and temporal sampling disparities, limitations in data resolution and variant detection, and genotype-phenotype uncertainties, rapid methodological progress and stronger ethical frameworks are expanding what can be inferred, making aDNA a promising tool for refining physiological pathways, their timing, and their drivers.

Humans↗

PubMed2026

Molecular adaptation of caspase genes to salinity stress in the tropical sea cucumber Stichopus monotuberculatus: A comparative analysis across echinoderms.

Apoptosis is an essential physiological process that plays a critical role in development and tissue homeostasis. Caspases, as central regulators of apoptosis, are crucial in controlling inflammation and cell death. In this study, we investigated the caspase gene family in Stichopus monotuberculatus to explore their potential roles in salinity stress adaptation. Five caspase genes were identified from the genome of S. monotuberculatus, including Smcaspase3, Smcaspase6, Smcaspase8a, Smcaspase8b, and Smcaspase8c. Phylogenetic analysis revealed that these Smcaspase genes clustered into distinct caspase subfamilies and showed high conservation with homologs from other echinoderms and representative vertebrates. Conserved motif and gene structure analyses showed relatively similar structural patterns within each clade, whereas divergence was observed among different subfamilies. Promoter analysis identified numerous cis-acting elements related to gene regulation, immune response, and growth and development. Expression profiling under salinity stress showed that Smcaspase8a was significantly upregulated, particularly under prolonged stress, whereas the other genes exhibited limited transcriptional responses. Our findings highlight caspase function in salinity stress and provide the foundation of molecular salinity adaptation mechanisms in S. monotuberculatus.

Animals↗

PubMed2026

Transcriptomic insights into thermal stress reveal physiological trade-off between thermal stress adaptation and reproductive investment in Spodoptera litura.

Spodoptera litura, a highly polyphagous lepidopteran pest, poses a major threat to agricultural productivity due to its remarkable adaptability to diverse environmental conditions. Although heat stress is known to trigger transcriptional reprogramming in insects, the molecular mechanisms underlying thermal stress responses in S. litura remain poorly understood. In the present study, fourth-instar larvae were exposed to acute heat stress (44 °C) and compared with control conditions (27 ± 1 °C) to investigate heat-induced transcriptional alterations affecting physiology and reproduction. High-quality RNA-Seq data achieved more than 80% mapping efficiency, with a total of 15,782 transcripts were identified. Transcriptome analysis of S. litura larvae showed 323 differentially expressed genes (DEGs), of which 262 genes were significantly upregulated and 61 were downregulated in heat-stressed larvae compared to the control group. The DEGs were associated with stress response, reproduction, signalling, proteostasis, detoxification, oxidative stress, metabolism, development, and chromatin regulation. Heat shock proteins genes, including HSP70, HSP90, and HSP27, together with co-chaperones such as TRET-1, STIP1, and Starvin, were strongly upregulated, indicating enhanced cellular protection against protein damage and oxidative stress under heat stress. Conversely, key reproductive and cell cycle-related genes, including BARR, CAPD2, FEO, CDK2 and MORULA, were significantly downregulated, suggesting reproductive impairment and developmental arrest. RT-qPCR validation corroborated the RNA-Seq findings, demonstrating a heat-induced physiological trade-off that prioritizes survival over reproduction. Consistent with these molecular responses, heat-stressed insects exhibited marked reproductive impairment, including significant reductions in gonadosomatic index, eupyrene sperm bundle count, mating frequency, mating success, female calling behaviour, copulation duration, fecundity, and egg fertility. Collectively, these findings provide comprehensive insights into the molecular basis of thermal adaptation in S. litura and demonstrate that acute heat stress compromises reproductive fitness while activating conserved stress-response pathways that promote short-term survival.

Animals↗

PubMed2026

Integrated physiological and transcriptomic analyses reveal coordinated gill responses to heat stress in pikeperch (Sander lucioperca).

Climate change-driven warming of aquatic environments has made thermal stress an increasingly important factor influencing fish physiological homeostasis. Given their central roles in respiration and osmoregulation, gills are particularly responsive to variations in ambient temperature. Histological examination, physiological measurements, and transcriptome profiling were integrated to investigate the mechanisms associated with heat stress-induced gill injury in pikeperch (Sander lucioperca). Histological analysis revealed that exposure to 29 °C directly caused structural damage to the gills of pikeperch. Oxidative status was evaluated by measuring malondialdehyde (MDA) levels and the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). MDA accumulation was significantly enhanced under heat stress, while antioxidant enzyme activities (SOD, POD, and CAT) displayed a transient increase followed by a subsequent decline. Transcriptome profiling showed marked enrichment of the protein processing in endoplasmic reticulum pathway after heat stress, suggesting activation of endoplasmic reticulum (ER) stress in pikeperch gills. With increasing stress duration, the unfolded protein response (UPR) appeared unable to re-establish ER homeostasis, shifting ire1 and atf6 toward a pro-apoptotic state. Protein-protein interaction (PPI) analysis further highlighted hub genes potentially involved in heat stress-induced ER stress and apoptosis. TUNEL staining and western blotting collectively confirmed that heat stress triggered apoptosis in pikeperch gill tissue. Overall, this study provides new insights into the physiological and molecular responses of pikeperch gills to heat stress and enhances our understanding of thermal stress adaptation in cold-water aquaculture species under climate change.

Animals↗