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Ultrasound protocols used to detect vascular gas emboli in divers: a systematic review.

INTRODUCTION: Venous gas emboli (VGE) detected via ultrasound can be used as a surrogate marker for decompression stress. While Doppler ultrasound is the historical gold standard, two-dimensional (2D) ultrasonography offers advantages for on-site monitoring, including a wider field of view and reduced dependence on noise-free environments. This systematic review evaluates 2D ultrasonography protocols used in decompression research since the 2015 International Meeting on Ultrasound for Diving Research, identifying methodological similarities, differences, and adherence to consensus recommendations. METHODS: A search of PubMed and Scopus identified studies using 2D ultrasound to detect VGE in divers. Inclusion criteria were: (1) use of 2D ultrasound, (2) detection of VGE or monitoring of decompression stress, (3) inclusion of a diver cohort, and (4) publication after 2015. Data extraction focused on VGE scoring systems, ultrasound hardware, measurement protocols, and operator experience. Risk of bias was assessed using ROBINS-I-V2, and compliance with the 2015 consensus recommendations was evaluated. RESULTS: Twenty studies were included. The Eftedal-Brubakk scale was most commonly used (n = 15), with cardiac ultrasound as the primary imaging modality; one study assessed a peripheral vessel. Common shortcomings included post-dive measurements lasting less than two hours, underreporting of operator experience and hardware specifications, limited individual-level data, and inappropriate use of parametric statistics for ordinal bubble grade data. No study fully complied with all consensus recommendations. CONCLUSIONS: This review demonstrates that, although two-dimensional ultrasound is widely used for post-dive VGE assessment, methodological heterogeneity with multiple shortcomings remain. Furthermore, nearly all studies restricted imaging to the heart, thus leaving peripheral vessel assessment largely unexplored.

Embolism, Air

Adaptations to breath-hold diving: from traditional divers to elite athletes.

Breath-hold diving exposes humans to repeated episodes of profound hypoxia and hypercapnia, eliciting physiological adaptations that enable prolonged underwater performance. This article summarises current knowledge on chronic adaptations in elite breath-hold athletes and traditional diving populations, including the Bajau sea nomads of Southeast Asia and the Korean Haenyeo divers. Evidence indicates that repeated apnoea induces adaptations across multiple physiological systems. Haematological changes include increased spleen size and enhanced splenic contraction, augmenting circulating haemoglobin and oxygen stores during apnoea. In elite divers, structured training can increase resting spleen volume, whereas the Bajau exhibit genetically associated splenic enlargement linked to variants near the PDE10A gene. Cardiopulmonary adaptations include modified pulmonary vascular responses to hypoxia, improved oxygen conservation, and metabolic shifts favoring efficient mitochondrial energy production. Molecular adaptations involve enhanced antioxidant defenses and activation of hypoxia-responsive pathways that may mitigate oxidative stress associated with repeated hypoxia-reoxygenation cycles. Emerging evidence also suggests neural plasticity and possible structural brain adaptations, although the long-term neurological consequences of chronic intermittent hypoxia exposure remain uncertain. Studies of traditional diving populations indicate that both phenotypic plasticity and genetic selection contribute to diving capacity, highlighting interactions between training and evolution. Despite these benefits, breath-hold diving also carries risks, including hypoxic blackout, decompression sickness, and potential neurological injury. Understanding the mechanisms underlying human tolerance to extreme hypoxia may have implications beyond diving physiology, including applications in cardiovascular medicine, hypoxic diseases, and rehabilitation. Further longitudinal, genomic, and mechanistic studies are needed to clarify the limits, benefits, and clinical relevance of these adaptations.

Humans

Handle with care: packaging the oocyte epigenome for the next generation.

During oocyte growth, substantial epigenetic programming occurs to establish a distinctive epigenome including appropriately patterned DNA methylation and histone modifications. Oocyte epigenetic programming must be tightly spatiotemporally regulated to ensure that a wide variety of epigenetic modifiers correctly establish their respective modifications to mediate precise control of gene expression. Furthermore, epigenetic modifications in oocytes include canonical and non-canonical genomic imprints, which are transmitted through meiosis to offspring. Significantly, disruptions in oocyte epigenetic programming can cause aberrant developmental outcomes in the next generation mediated by altered imprinting. Polycomb repressive complex 2 is an important epigenetic modifier that establishes histone 3 lysine 27 trimethylation and non-canonical imprints during mouse oogenesis, which are important for normal offspring development. While it is widely recognised that altered oocyte epigenetic programming can disrupt offspring development, mechanisms controlling maternal epigenetic inheritance remain poorly understood. The possibility remains that non-canonical imprinting exists in humans, although this requires confirmation. This review discusses mouse and human oocyte epigenetic programming including interactions between various epigenetic modifiers and modifications that form the unique oocyte epigenome. Understanding how oocyte epigenetic programming is regulated will be crucial in discerning how changes to the oocyte epigenome can disrupt epigenetic memory and alter developmental outcomes in offspring.

Animals

Don't judge a sperm by its cover.

Male fertility is primarily assessed using descriptive semen parameters, such as sperm concentration, motility and morphology. These conventional parameters provide an initial assessment of male reproductive health and may explain why a couple is struggling to conceive; however, they are not a direct measure of fertility potential. Growing evidence suggests that spermatozoa transmit far more than paternal DNA. Alongside the genome, spermatozoa deliver proteins, RNA and epigenetic information that are responsive to environmental and lifestyle exposures, and can influence embryo development, pregnancy outcomes and offspring health. This emerging concept challenges the view that male fertility is defined solely by successful conception. Here, we discuss evidence that spermatozoa act as carriers of environmental and lifestyle 'memories', transmitting molecular information shaped by paternal health to the next generation. We further consider the implications for assisted reproductive technologies, which select spermatozoa largely on their capacity to move while overlooking the molecular cargo they transmit. Recognising spermatozoa as vectors of environmental information reframes male fertility and highlights the need for biomarkers that assess molecular integrity alongside conventional clinical parameters.

Male

Pangenome-wide identification and expression analysis of the chalcone synthase (CHS) gene family in five yellowhorn spp.

Chalcone synthase (CHS) is a pivotal enzyme in flavonoid biosynthesis involved in plant development, defense, and secondary metabolism. Xanthoceras sorbifolium (yellowhorn) is a medicinal and ornamental species with high resistance to environmental stresses, but its CHS gene family remains uncharacterized. We performed a pangenome-wide identification of CHS genes across five yellowhorn genomes (Xzs4, Xwf8, Xjg, Xg11, and Xzg2). Across the five yellowhorn genomes, 27 CHS genes were identified and classified into four core pangenes, present in all five genomes, and two dispensable genes, present only in a subset of genomes. Phylogenetic analysis grouped these genes into three major clades, and chromosomal mapping and duplication analyses identified four tandemly duplicated gene pairs under purifying selection. The analyses of conserved structural features, including protein motifs and exon-intron organization, together with promoter cis-regulatory elements and gene ontology annotation, further indicated the potential involvement of CHS genes in flavonoid biosynthesis and stress-responsive mechanisms. Gene expression profiling identified significant upregulation of Xg11_CHS1 and Xg11_CHS3 under cold and drought stress, with tissue-specific expression patterns. These findings provide valuable insights into the evolution, functional diversification, and stress-responsive roles of the CHS gene family, identifying candidate genes for future studies targeting stress tolerance and flavonoid biosynthesis in yellowhorn.

Acyltransferases

Distinct functions of mammalian RAD51 paralogs in genome maintenance.

RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, and XRCC3) are evolutionarily conserved essential proteins for cell survival and genome maintenance. RAD51 paralogs were originally identified to play a role in homologous recombination-mediated repair of DNA double-strand breaks (DSBs). However, investigations over the last decade have uncovered new roles of RAD51 paralogs beyond DSB repair in replication stress responses, including replication fork progression, fork stability, and its restart. Recent structural studies have not only uncovered the molecular architecture of previously known RAD51 paralog complexes but also identified novel paralog complex assemblies, providing mechanistic insights into their various genome-maintenance functions. Additionally, a role for RAD51 paralogs in resolving R-loops has been identified, and studies with cancer-associated variants suggest that RAD51 paralogs are potential determinants of cancer susceptibility and therapeutic responses. In the present review, we highlight the recently deciphered structures and novel functions of RAD51 paralog complexes and discuss the clinical and therapeutic implications.

Rad51 Recombinase

Insights into the regulation of the HOTAIR proximal promoter.

HOTAIR (HOX transcript antisense RNA) is a HOXC-cluster long intervening non-coding RNA (lincRNA) whose cancer relevance is tightly coupled to how its transcription is wired into hormone, hypoxia, inflammatory, and developmental signaling. HOTAIR is known to associate with cancer cell proliferation, motility, tumor invasion, and metastasis. The present mini-review focuses on the regulatory architecture and mechanistic complexity of HOTAIR transcriptional regulation, with emphasis on three organizing principles. First, we consider the impact of promoter choice between a canonical proximal promoter (P1), which supports the 2.2-2.4 kb transcript, and an alternative upstream promoter/TSS (P2), which contributes to context-dependent transcription initiation. Second, we examine the long-distance enhancer-promoter communication between HOTAIR distal enhancer and P1/P2. Third, we summarize the recent epigenetic and epi-transcriptomic mechanisms involved in HOTAIR transcript initiation and elongation. A combination of these events determines isoform-specific transcription to govern cell-type-, context-, and cancer specific modulation of HOTAIR expression that promotes tumor formation and cancer progression. Finally, the review proposes how large-scale RNA datasets, long-read sequencing, and isoform-specific studies can refine our understanding of this versatile lincRNA's regulation.

Humans

RENOIR phase 3 rituximab-lenalidomide vs rituximab as maintenance treatment in relapsed/refractory follicular lymphoma.

Maintenance treatment in older patients with relapsed or refractory (R/R) follicular lymphoma (FL) remains an area of investigation. RENOIR was a multicenter, phase 3, open-label randomized trial conducted by the Fondazione Italiana Linfomi (FIL) in older patients with R/R FL after 1 or 2 previous therapies. Patients achieving partial response or complete response (CR) after 4 to 6 cycles of standard rituximab (R)-based chemotherapy were randomized 1:1 to maintenance with R alone (standard arm) or R plus lenalidomide (R2; experimental arm). The primary end point was 2-year progression-free survival (PFS) from randomization, with an expected hazard ratio (HR) of 0.5. A total of 152 patients (median age, 71 years) were enrolled. After induction, 129 (85%) achieved an overall response (CR, 58%) and were randomized to R (n = 65) or R2 (n = 64). At a median follow-up of 68 months, the 2-year PFS was 73% in the R2 arm and 64% in the R arm. An unplanned hypothesis-generating subgroup analysis showed a greater 2-year PFS benefit with R2 in patients aged <70 years: R2, 96% vs R, 69%. Two-year overall survival rates were similar (R2, 80% vs R, 89%). Grade 3/4 adverse events were more frequent in R2, mainly neutropenia and gastrointestinal disorders. In conclusion, the primary end point of the study was not met, and R2 maintenance did not significantly improve 2-year PFS in older patients with R/R FL, although a numerical benefit was observed. R2 showed a more favorable benefit-risk profile in patients aged <70 years, whereas in older patients careful consideration of individual tolerability is warranted. This trial was registered at www.clinicaltrials.gov as NCT02390869.

Humans

Validation of the newly introduced Deauville score 5a for patients treated for advanced-stage classic Hodgkin lymphoma.

The Lugano Imaging Committee recently refined the Deauville score (DS), subdividing DS5 into DS5a (>2&#xd7; liver uptake without new lesions) and DS5b (new lesions). We investigated whether this improves prognostic discrimination at interim positron emission tomography (PET) after 2 cycles (PET-2) in patients with advanced-stage classical Hodgkin lymphoma (AS-cHL) treated in recent German Hodgkin Study Group randomized phase 3 trials. The primary analysis cohort was HD18 postamendment standard arms (uniform treatment with 6 cycles of escalated doses of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone [eBEACOPP]); sensitivity cohorts were HD18 intention-to-treat and HD21 eBEACOPP and brentuximab vedotin, etoposide, cyclophosphamide, doxorubicin, dacarbazine, and dexamethasone arms. Progression-free survival (PFS) was analyzed by landmark Cox models starting at PET-2. DS5a was infrequent (4%-6% across cohorts; 39/639, 67/1745, 33/568, and 29/560). In the primary cohort, DS5 was associated with inferior PFS vs DS1 to DS3 (hazard ratio [HR], 3.00; 95% confidence interval [CI], 1.25-7.23) and vs DS1 to DS4 (HR, 2.35; 95% CI, 1.01-5.50). Across sensitivity cohorts, DS5a remained adverse compared with DS1 to DS4 (HR range, 2.57-5.47), whereas DS4 according to the new definition did not consistently separate from DS1 to DS3, which is likely a result of PET-adapted treatment. Overall survival trends were concordant, but interpretation is limited by few events. To our knowledge, this is the first prognostic validation of the refined DS in prospectively randomized trial populations. The newly introduced DS5a isolates a small high-risk AS-cHL, which further supports risk assessment and adaptation using quantitative biomarkers from PET. The HD18 and HD21 trials were registered at www.clinicaltrials.gov as NCT00515554 and NCT02661503, respectively.

Humans

Molecular origins of pH gradients in charge-regulated biomolecular condensates.

Biomolecular condensates exhibit spontaneous electrochemical microenvironments characterized by asymmetric ion distributions and pH gradients that emerge from protein-sequence-dependent charge regulation. Despite their biological importance, mechanistic understanding of these microenvironments has been constrained by the absence of computationally tractable frameworks capable of treating proton exchange, counterion partitioning, and buffer equilibria on consistent thermodynamic footing. Here, we introduce the buffered Charge-Regulation Monte Carlo (b-CR-MC) framework, which couples grand-canonical exchange of ions and buffer species with explicit charge regulation of titratable residues. By extending the CR-MC ion-merging strategy to multicomponent reservoirs and employing the restricted primitive model, b-CR-MC achieves computational efficiency while maintaining thermodynamic rigor, achievingquantitative agreement with the more expensive generalized grand-reaction Monte Carlo approach. Applied to full-length FUS (net positive) and PGL-3 (net negative) under physiological conditions, the framework reveals sequence-dependent pH gradients: the dense phase of FUS exhibits an alkaline shift, while that of PGL-3 exhibits an acidic shift, in both cases driving the condensate interior toward the protein's isoelectric point. Slab-geometry simulations further resolve the Donnan potential and continuous ion profiles across the condensate interface, confirming the direction of these electrochemical shifts. Additionally, we identify spatially resolved buffer depletion within dense phases, establishing that dynamic charge regulation is a primary determinant rather than a secondary correction to condensate electrochemistry. By establishing a sequence-resolved, thermodynamically consistent computational platform, b-CR-MC enables quantitative prediction of how mutations and post-translational modifications reprogram condensate microenvironments across biological and pathophysiological contexts.

Hydrogen-Ion Concentration

Identification and expression validation of key genes of Xiaozhengtongluo formula in the treatment of diabetic nephropathy by Mendelian randomization.

Xiaozhengtongluo formula (XZTL) has a positive effect on the treatment of diabetic nephropathy (DN), but its mechanism is not fully understood. Therefore, it is important to explore the key genes of XZTL in the treatment of DN. Differentially expressed genes (DEGs) between DN and control obtained from GSE96804, drug target genes of XZTL, and disease target genes of DN obtained from public databases were intersected. Genes of intersection were defined as candidate genes. Next, Mendelian randomization (MR) analysis was used to ascertain the causal associations between candidate genes and DN. Afterwards, key genes were confirmed through receiver operating characteristic (ROC) curve analysis and expression validation. Subsequently, enrichment analysis, molecular regulatory network analysis, and molecular docking were conducted. Finally, experimental verification of the expression levels of key genes was performed through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Altogether, 29 candidate genes were screened via MR analysis, identifying APOD, IGFBP3, and LPL as significantly associated with DN. IGFBP3 and APOD were risk factors, whereas LPL was protective. Consistent expression trends across training and validation datasets defined them as key genes. All three were co-enriched in 26 pathways, including oxidative phosphorylation. Regulatory networks showed MIR497HG/hsa-miR-19a-3p regulated IGFBP3, and NEAT1/hsa-miR-29a-3p regulated LPL; IGFBP3 and LPL were co-targeted by SP3 and SP1. Molecular docking revealed APOD-baicalein, LPL-oleic acid, and IGFBP3-quercetin binding, suggesting therapeutic potential. RT-qPCR confirmed aberrant expression of these genes in DN, which was normalized by XZTL intervention. In this study, three key genes (APOD, IGFBP3, and LPL) of XZTL in the treatment of DN were finally obtained, providing mechanistic clues for understanding XZTL's multi-target mechanism and providing experimentally tractable candidate targets for DN molecular subtyping, targeted therapeutic development, and precision medicine approaches in TCM.

Diabetic Nephropathies

Chromosome painting in plants: history and future perspectives.

Chromosome painting was developed in mammalian species nearly four decades ago and rapidly became a powerful tool for chromosome identification, comparative cytogenetics, and evolutionary genome analysis. Comparative chromosome painting among diverse mammals generated much of the foundational knowledge of chromosome structure, chromosomal rearrangements, and karyotype evolution before the advent of whole-genome sequencing. Although chromosome painting was first demonstrated in plants in 2001, its applications remained largely restricted to a few plant lineages until the development of oligonucleotide (oligo)-based chromosome painting in 2015. During the last decade, oligo-based chromosome painting has transformed plant cytogenetics, enabling many investigations that were previously impossible. These studies have provided new insights into meiotic chromosome pairing, crossover formation, chromosome fusion, karyotype stability, and chromosome evolution across diverse plant lineages. This review summarizes the history of technological development of chromosome painting in plants, highlights major discoveries enabled by oligo-based chromosome painting, and discusses future opportunities, particularly the integration of chromosome painting with three-dimensional chromosome and genome biology.

Chromosome Painting

Distinct cerebellar and inner-ear phenotypes in Atoh1 promoter-proximal deletion mice.

OBJECTIVE: Atoh1 is essential for the development of the cerebellum and inner ear, but the in vivo role of its promoter-proximal region remains incompletely understood. We generated deletion lines targeting the Atoh1 promoter-proximal region containing C sites and examined their phenotypes in the cerebellum and inner ear. METHODS: Using the CRISPR-Cas9 genome editing method, mice with deletions in the Atoh1 promoter-proximal region containing C sites were generated, and four independent deletion lines were established. Gross morphology and histology of the cerebellum and inner ear were examined in 2-month-old mice. RESULTS: Four independent deletion alleles were obtained and designated line A to line D in ascending order of deletion size. In the cerebellum, gross examination and sagittal sections showed progressively more severe hypoplasia from line A to line D, accompanied by reduced foliation and disorganization of cortical architecture. The granule cell layer was progressively reduced, whereas Purkinje cells were relatively preserved. Behavioral abnormalities were detected only in the most severely affected line. In the inner ear, the maculae of the otolith organs were relatively preserved across all lines. The ampullary cristae were relatively preserved in lines A-C but showed hair-cell loss in line D. Cochlear phenotypes were more severe: line A retained relatively preserved inner hair cells with reduced outer hair cells, whereas lines B-D showed near-complete loss of hair cells and marked disruption of the organ of Corti in the analyzed regions. Descriptive quantitative analyses of available specimens supported progressive cerebellar hypoplasia, relative macular preservation, line D crista involvement, and severe cochlear hair-cell loss in lines B-D. CONCLUSION: Deletion of the Atoh1 promoter-proximal region produced distinct tissue-specific phenotypes in vivo. These findings suggest that the Atoh1 promoter-proximal region is differentially required in the cerebellum and inner ear and that its contribution varies among vestibular and cochlear sensory organs.

Atoh1

Meropenem-Colistin Combination Mitigates Porin-Associated Carbapenem Resistance Development in Ertapenem-Mono-Resistant Enterobacterales.

BACKGROUND: Non-carbapenemase-producing Enterobacterales with isolated ertapenem resistance (ETP-mono-R) may represent an early stage in the evolution toward broader carbapenem resistance, but whether further resistance induction occurs and its underlying mechanisms remain poorly understood. METHODS: Resistance induction was assessed in three Escherichia coli, four Klebsiella pneumoniae, and two Enterobacter cloacae isolates through serial exposure to subinhibitory concentrations of meropenem (MEM), imipenem, ceftazidime-avibactam, or colistin (COL), with antibiotic-free passaging for reversion. Resistance induction under MEM+COL was evaluated separately. Whole-genome sequencing (WGS), targeted porin-gene Sanger sequencing, and transcriptional analysis were used to characterize resistance mechanisms across induction stages. RESULTS: Subinhibitory MEM exposure rapidly selected for carbapenem resistance through porin-associated alterations in a species-specific manner. E. coli accumulated loop-region mutations in ompC, while K. pneumoniae predominantly developed disruptive mutations in ompK36, both accompanied by marked transcriptional downregulation. In contrast, E. cloacae retained wild-type porins but showed increased MEM MICs, suggesting a non-porin-mediated mechanism. Subinhibitory exposure to COL alone rapidly induced colistin resistance but was associated with decreased carbapenem MICs. Co-exposure to MEM and COL significantly delayed resistance development and reduced MIC increases (all P < 0.05). Targeted sequencing of 26 non-carbapenemase-producing K. pneumoniae isolates resistant to all carbapenems revealed widespread disruptive ompK36 alterations, including the S337P substitution identified experimentally, consistent with a shared permeability-loss pathway. CONCLUSIONS: In ETP-mono-R Enterobacterales, subinhibitory carbapenem exposure promotes carbapenem resistance, with porin-associated mechanisms predominating in E. coli and K. pneumoniae. Co-exposure to COL attenuates this process, suggesting a potential strategy to delay the emergence of carbapenem resistance.

Enterobacterales

The next-generation biomarkers in early-stage triple negative breast cancer.

PURPOSE OF REVIEW: Despite maximal neoadjuvant chemoimmunotherapy, nearly 40% of early-stage triple-negative breast cancer (TNBC) patients fail to achieve pathological complete response, underscoring an urgent need for biomarkers capable of guiding treatment modulation. This review summarizes recent advances in tumor-infiltrating lymphocytes (TILs), circulating tumor DNA (ctDNA), and genomic signatures, exploring their potential integration into clinical decision-making. RECENT FINDINGS: TILs remain the most validated, cost-effective prognostic biomarker, although standardized scoring is still needed to overcome interobserver variability. ctDNA has emerged as a dynamic, real-time prognostic tool, with postneoadjuvant detection strongly predicting relapse and worse outcomes. Nonetheless, optimal sampling timing remains undefined. Genomic signatures, particularly TNBC-DX, provide standardized, reproducible prognostic information by integrating immune and proliferative gene expression. Emerging data suggest that combining these biomarkers may offer a complementary and synergistic effect. SUMMARY: Multibiomarker integration, supported by prospective validation and automated models, represents a promising approach to personalize treatment algorithms in early-stage TNBC, balancing efficacy and toxicity while guiding escalation and de-escalation strategies.

artificial intelligence