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Congenital Laryngomalacia: Pathophysiology, Clinical Spectrum, and Holistic Management.

Congenital laryngomalacia is the most common cause of infant stridor and arises from interacting structural, neuromuscular, and inflammatory mechanisms that produce dynamic supraglottic collapse. Disease severity spans mild stridor to significant obstruction, aspiration, and failure to thrive, often influenced by comorbid medical conditions. Diagnosis relies on flexible laryngoscopy supported by instrumental swallowing studies and microdirect laryngoscopy and bronchoscopy when indicated. Most infants respond to conservative management, particularly targeted feeding modifications, while acid suppression offers benefit in selective cases. Supraglottoplasty provides effective, durable improvement for severe disease and significantly enhances infant outcomes and family quality of life.

Humans

Advanced/Novel Stenting for Pediatric Dynamic Airway Collapse.

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

Humans

Norgestrel drives mitochondrial collapse and plasma membrane impairment in Pacific oyster (Crassostrea gigas) sperm by triggering premature acrosome reaction.

The toxic mechanisms of norgestrel (NGT), an emerging marine pollutant, on the sperm from externally fertilized invertebrates remain elusive. This study employed an integrated physiological and multi-omics framework to elucidate how NGT (10 and 1000 ng/L) disrupts acrosome reaction (AR) signaling machinery, thereby impairing the functional integrity of Pacific oyster (Crassostrea gigas, also known as Magallana gigas) sperm. Exposure to NGT triggered a significant, dose-dependent premature AR, characterized by elevated acrosin activity and a loss of acrosomal integrity. Multi-omics integration supports a model in which this premature exocytosis is linked to signaling disturbances, including disruption of calcium signaling and reduced transcript abundance of calmodulin (CaM) and the primary recognition protein zonadhesin (Zan). This signaling interference induced an premature AR, subsequently driving a cascade of bioenergetic and structural failures. At the mitochondrial level, NGT induced abnormal mitochondrial permeability transition pore (mPTP) opening and elevated the transcript levels of antioxidant defense genes (e.g., peroxiredoxin-5, PRDX5). These alterations indicate the occurrence of mitochondrial collapse. Concurrently, scanning electron microscopy verified localized plasma membrane wrinkling and pore formation in sperm. In addition, NGT exposure decreased the transcript abundance of cytoskeleton-related genes, including solute carrier family 26 member 6 (SLC26A6), actin (ACT), and tubulin polymerization promoting protein family member 3 (TPPP3). These molecular changes further disrupted membrane phospholipid homeostasis, as represented by altered glycerophospholipid metabolism. At the same time, cumulative cellular stress was associated with decreased transcript abundance of cytoprotective factors (e.g., baculoviral IAP repeat-containing proteins, birc2) and changes in apoptosis-related genes consistent with activation of a caspase-8-mediated apoptotic programme. In conclusion, NGT, as a representative synthetic progestin, exerts reproductive toxicity by interfering with signaling mediators to induce premature AR, which subsequently exhausts metabolic energy and triggers plasma membrane impairment. These findings provide a critical mechanistic basis for the aquatic ecological risk assessment of synthetic progestins.

Animals

Divergent responses of the gill, hepatopancreas, and eyestalk to acute alkalinity stress in Penaeus vannamei: Osmoregulatory compromise, metabolic trade-off, and endocrine disruption.

The expansion of aquaculture into inland saline-alkali waters is constrained by high carbonate alkalinity (CA), a severe environmental stressor for crustaceans. However, the systemic molecular mechanisms underlying its lethal toxicity remain poorly understood. In this study, we employed a comparative transcriptomic approach to investigate the tissue-specific responses of Pacific white shrimp, Penaeus vannamei, under acute lethal stress (48 h-LC50). We focused on three functionally distinct organs: the gill, hepatopancreas, and eyestalk. The results revealed a systemic but highly tissue-specific transcriptomic response. The gill, as the primary interface, exhibited severe structural impairment and critical failure of osmoregulation, highlighted by the significant downregulation of delta-1-pyrroline-5-carboxylate synthetase (P5CS). In contrast, the hepatopancreas initiates a profound metabolic trade-off, sacrificing growth-related pathways to bolster a robust antioxidant defense system, as evidenced by the activation of sulfur metabolism and high protein turnover. The eyestalk displayed a striking disconnect between hyperactivated stress signaling pathways (e.g., mTOR/FoxO) and the collapse of its protein secretory machinery, marked by the suppression of the ER translocon component Sec61. Collectively, our findings suggest that lethal alkalinity toxicity in P. vannamei results from systemic collapse driven by a complex interplay of osmoregulatory failure, metabolic trade-offs, and endocrine disruption. This study provides a comprehensive molecular snapshot of an organism at its physiological limit, offering novel insights into the adaptive strategies and ultimate tolerance boundaries of crustaceans in extreme environments.

Animals

High-flow nasal cannula oxygenation in sedated endoscopy for high-risk obstructive sleep apnea patients: study protocol for a multicentre randomised controlled trial.

BACKGROUND: Hypoxemia is the most common adverse event during sedated gastrointestinal endoscopy. Patients with high obstructive sleep apnea (OSA) risk (STOP-Bang &#x2265;5) are susceptible due to sedation-induced loss of upper airway tone exacerbating airway collapsibility. Although high-flow nasal cannula (HFNC) benefits general at-risk populations, its efficacy in this specific cohort remains uncertain, as its mild positive pressure falls far below therapeutic continuous positive airway pressure levels for moderate-to-severe OSA, questioning its ability to stent the collapsible airway. Our prior proof-of-concept study in this cohort observed a 5% incidence of hypoxemia with HFNC, confirming feasibility and safety and justifying this confirmatory trial. METHODS: This prospective, multicenter, randomized controlled single-blind trial will enroll 600 adults (STOP-Bang score &#x2265;5) undergoing elective sedated gastroenteroscopy across three centers. Participants will be 1:1 randomized (stratified by center) to HFNC (30&#x2009;L/min pre-oxygenation, 60&#x2009;L/min post-induction) or conventional nasal cannula (6&#x2009;L/min). Both groups receive standardized propofol-alfentanil sedation. The primary outcome is the proportion of patients with at least one episode of hypoxemia (SpO2 75%-90% <60&#x2009;s). Secondary outcomes include the proportion of patients with at least one episode of severe hypoxemia (SpO2 <75% or 75%&#x2264;SpO2<90% &#x2265;60&#x2009;s), the proportion with subclinical respiratory depression (90%&#x2264;SpO2<95%), and the frequency of other adverse events. DISCUSSION: This trial will provide definitive evidence on HFNC's efficacy in high-risk OSA patients, addressing whether it can overcome pressure limitations to prevent hypoxemia. Results are expected to inform sedation management guidelines, establish a new standard of care for this subgroup, and enhance procedural safety. TRIAL REGISTRATION: The trial was registered at the ClinicalTrials.gov on 14 December 2025 (NCT07307560).

Humans

Respiratory effects of recruitment maneuvers according to lung recruitability assessed by electrical impedance tomography in patients with acute respiratory distress syndrome.

Recruitment maneuvers (RM) can improve oxygenation in patients with acute respiratory distress syndrome (ARDS), but their physiological effects depend on lung recruitability. This secondary analysis of a randomized controlled trial (RCT) evaluated oxygenation, respiratory mechanics, regional ventilation, and cardiorespiratory adverse events responses to a RM followed by electrical impedance tomography (EIT)-guided PEEP titration, using EIT to assess lung recruitability. In this study, fifty patients with moderate-to-severe ARDS underwent a stepwise RM followed by individualized PEEP titration guided by EIT. Lung recruitability was determined using the collapse index at PEEP 6 cmH&#x2082;O (CLPEEP6), defined as the proportion of collapsed lung at this PEEP level. Patients were classified into high- and low-recruitability groups based on median CLPEEP6 values. Oxygenation (PaO&#x2082;/FiO&#x2082;), static compliance (Cstat), driving pressure (Pdriv), regional ventilation distribution, and cardiorespiratory adverse events were compared before and after RM, during subsequent individualized EIT-guided PEEP titration. In patients with high recruitability (CLPEEP6&#x2009;>&#x2009;12.5), the PaO&#x2082;/FiO&#x2082; ratio and Cstat increased significantly after RM (PaO&#x2082;/FiO&#x2082;: 100.8&#x2009;&#xb1;&#x2009;30.3 vs. 125.4&#x2009;&#xb1;&#x2009;38.3&#xa0;mmHg, p&#x2009;<&#x2009;0.05; Cstat: 21.5&#x2009;&#xb1;&#x2009;5.8 vs. 28.0&#x2009;&#xb1;&#x2009;7.0&#xa0;mL/cmH&#x2082;O, p&#x2009;<&#x2009;0.001), Pdriv decreased (19.1&#x2009;&#xb1;&#x2009;3.5 vs. 15.6&#x2009;&#xb1;&#x2009;3.2 cmH&#x2082;O, p&#x2009;<&#x2009;0.001). EIT demonstrated a posterior redistribution of ventilation after RM. In contrast, patients with low recruitability (CLPEEP6&#x2009;&#x2264;&#x2009;12.5) showed no significant mechanical or oxygenation improvement and transient hypotension, arrhythmia, and desaturation appeared numerically more common in this group. No barotrauma or cardiac arrest occurred, and ICU mortality was similar between groups. A strategy combining a RM with subsequent individualized EIT-guided PEEP titration was associated with improved oxygenation and lung mechanics in patients with high lung recruitability, whereas patients with low recruitability showed limited physiological benefit, with cardiorespiratory adverse events appearing numerically more frequent. The EIT-derived CLPEEP6 index represents a feasible and clinically applicable https://clinicaltrials.gov/study/NCT06733168.

Humans

Metatranscriptomic analysis of viral sequences associated with Culex nigripalpus at an Alabama aquaculture site.

Mosquitoes associated with aquaculture habitats can harbor diverse viruses, yet the viromes of many locally abundant species remain poorly characterized. At an aquaculture-associated site in Auburn, Alabama, we surveyed mosquito populations and found Culex nigripalpus to be the dominant species collected. To characterize viruses associated with this mosquito, we performed RNA-seq on pooled female Cx. nigripalpus and compared complementary bioinformatic workflows for viral detection and genome recovery. One workflow removed host-associated reads by mapping to the closest available mosquito reference genome prior to assembly, whereas a second workflow used fully de novo assembly and viral database annotation. Additional protein-level filtering, cross-workflow comparison, and comparison of Trinity and rnaSPAdes assemblies were used to prioritize well-supported viral candidates. Across the original analyses, 16 submitted accessions corresponding to 12 collapsed virus/name groups were recovered, including Merida virus, Hubei mosquito virus 5, Zhejiang mosquito virus, Hubei virga-like virus 3, Rinkaby virus, Elemess virus, Qingnian mosquito virus, Serbia narna-like virus 2, XiangYun narna-levi-like virus 8, Ecclesville picorna-like virus, and baculovirus-like fragments. Several candidates were supported across multiple workflows, while others were recovered only under specific analytical conditions, indicating that candidate recovery was influenced by assembly and filtering choices. Selected viral contigs were independently supported by RT-PCR amplification. Overall, these results provide a first characterization of viral sequences associated with Cx. nigripalpus from an Alabama aquaculture-associated site and show that comparison across assembly and filtering strategies helped prioritize the most consistently supported viral candidates.

Animals

A system-level metastable model of cancer evolution: integrating replication stress, cell cycle deregulation and chromosomal instability.

INTRODUCTION: Cancer cell proliferation occurs within the context of persistent genomic instability. In this review, we propose the RS-CCD-CIN axis as a systems-level framework in which replication stress (RS), cell cycle deregulation (CCD) and chromosomal instability (CIN) form an interdependent triad that shapes tumour evolution. This axis represents a constrained metastable state in which genomic instability is tolerated and buffered. The objective of this review is to synthesize the current understanding of how the RS-CCD-CIN axis contributes to tumour heterogeneity, adaptability and therapy response. DISCUSSION: Evidence indicates that RS, CCD and CIN operate as a dynamic, interconnected network rather than as independent processes. Replication stress induces DNA damage and mutagenesis, while partial checkpoint disruption permits cells with unresolved lesions to proliferate. Chromosomal instability generates both structural and numerical alterations, contributing to intratumoural heterogeneity. Together, these processes facilitate adaptation to environmental and therapeutic pressures. Extrachromosomal DNA, micronuclei formation and cytosolic DNA signalling, including the cGAS-STING pathway, connect genomic instability to adaptive responses and immune modulation. Single-cell and spatial profiling reveal temporal and spatial variability in RS, CCD and CIN states, highlighting the limitations of static biomarkers. Therapeutically, targeting individual components often yields limited durability, whereas approaches that simultaneously perturb multiple aspects of the RS-CCD-CIN axis may improve clinical outcomes. CONCLUSIONS: This review highlights the RS-CCD-CIN axis as a fragile and metastable architecture that supports cancer evolution, while also being susceptible to collapse. A deeper understanding of this interconnected framework may inform the development of therapeutic strategies and enhance the management of resistance.

Humans

Beyond multidimensionality: a systematic review of recurrent frailty archetypes in community-dwelling older adults.

BACKGROUND: Frailty is a clinically heterogeneous geriatric syndrome commonly summarised using physical or multidomain severity scores. Whether person-centred analyses identify recurring within-frailty configurations has not been systematically examined in community-dwelling older adults. METHODS: We searched PubMed, Embase, MEDLINE, and CINAHL (January 2000-November 2025) for cross-sectional studies using latent class, latent profile, or analogous clustering methods to derive frailty subgroups. Quality was assessed using the AHRQ checklist and a purpose-built appraisal of person-centred model reporting. Study-derived classes were mapped in duplicate to a structured archetype framework developed through comparison of class-defining features across studies. RESULTS: Fourteen reports representing 12 independent datasets from eight countries were included. Six configurations were identified: minimally impaired reference, mobility-physical, nutritional-metabolic, cognitive-predominant, combined cognitive-physical, and psychosocial/mood-predominant. Convergence was measurement-dependent. The reference and mobility-physical configurations recurred across physical-only and multidomain indicator sets, while the combined cognitive-physical configuration appeared across several multidomain frameworks but required cognition to be measured. The remaining configurations emerged only when their defining domains were included. Evidence of prognostic value beyond aggregate frailty severity came from one deficit-index study. Collapsing shared-provenance reports and excluding the boundary-eligible study did not alter recurrence; excluding the Croatian dataset left five configurations recurrent, with the cognitive-predominant configuration supported by one independent dataset. CONCLUSIONS: Person-centred analyses identify recurring within-frailty configurations, but their apparent stability is partly measurement-dependent. A five-configuration core persisted after exclusion of the Croatian dataset, whereas the cognitive-predominant configuration remained weakly replicated. Harmonised indicators and rigorous external validation are needed before clinical application.

Humans

Mitochondrial dysfunction in muscle cells induced by snoring vibrations.

Snoring-related vibrations have been proposed as a pathogenic factor contributing to upper airway muscle dysfunction in patients with obstructive sleep apnea (OSA). To investigate whether exposure to snoring vibration is linked to muscle weakness, we used an in vitro vibration model to examine its effects on mitochondrial homeostasis in L6 muscle cells at 8, 12, 24, and 48&#xa0;h. The findings were then compared with mitochondrial alterations in the upper airway muscles from snorers and patients with OSA. Proteomic analysis of L6 myoblasts revealed extensive remodeling of the mitochondrial proteome at 8&#xa0;h, affecting pathways involved in oxidative phosphorylation, protein import, ribosome biogenesis, and RNA processing. Respiratory chain remodeling was subunit-specific, with increased abundance of selected components of Complexes I, IV, and V, including NDUFS4, COX5A, and ATP5PD. However, reductions in spliceosome-associated factors, such as SRSF2 and DDX46, along with alterations in mitochondrial ribosomal proteins, indicated impaired RNA processing and protein synthesis. Furthermore, both proteomic and transcriptomic analyses revealed activation of a mechanosensing-mechanotransduction axis, with early upregulation of integrin subunits and mechanosensitive ion channels, followed by transient activation of focal adhesion signaling. Despite transcriptional upregulation of selected Complex IV subunits Cox5a and Cox6a2, this response was accompanied by accumulation of unspliced pre-mRNA, indicating impaired RNA processing efficiency and a decoupling between transcript and protein levels. Real-time Seahorse assay revealed a collapse of mitochondrial respiration and glycolytic reserve at 8&#xa0;h. Although mitochondrial oxygen consumption recovered after 48&#xa0;h, the ability to dynamically upregulate glycolysis remained impaired. In patients, muscle capillarization was impaired, COX activity was reduced, and mitochondrial organization was disrupted. Moreover, transcription of Complex IV subunits COX5A and COX6A2 was, as in vibrated L6 cells, upregulated, suggesting a mismatch between transcript levels and protein expression. We conclude that snoring-induced vibrations are an unrecognized stressor that disrupts mitochondrial homeostasis in muscle by impairing RNA processing, protein synthesis, and mechanotransduction-driven mitochondrial remodeling, leading to transcript-protein uncoupling and likely muscle dysfunction.

Humans