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PubMed2026

A chromosome-level, haplotype-resolved genome assembly for the barn owl, Tyto alba.

Recent advances in long-read sequencing have enabled near telomere-to-telomere (T2T) assemblies across diverse taxa. However, avian genomes remain challenging due to numerous microchromosomes, small, typically < 20Mb, DNA molecules that are gene-, GC-, and repeat-rich. As a consequence, microchromosomes are often missing from genome assemblies. Here, we present a chromosome-level, haplotype-resolved genome assembly for the Western barn owl (Tyto alba). Using a trio-binning strategy with Illumina parental reads combined with PacBio HiFi and Oxford Nanopore Technologies data, we generated two phased contig sets. These were scaffolded into 40 linkage groups using a linkage map. Comparative analyses identified unplaced HiFi scaffolds corresponding to microchromosomes, which we integrated into six additional microchromosomes using long reads information. The two assemblies present 46 chromosomes, matching the karyotype of the species. They exhibit strong synteny between parental haplotypes, except for a ∼38 Mb complex region on chromosome 7 containing nested inversions. This high-quality reference provides a haplotype-resolved and chromosome-level genome for Strigiformes, enabling fine-scale studies of structural variation and avian genome evolution.

Tyto alba↗

PubMed2026

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↗

PubMed2026

Proteomic profiling reveals that DPP4 overexpression increases cell adhesion, inhibits cell migration, and restores androgen sensitivity in prostate cancer.

Dipeptidyl peptidase-4 (DPP4), a serine protease with both enzymatic and non-enzymatic roles, has emerged as a context-dependent modulator of tumor progression. In the present study, we investigated the expression and function of DPP4 in androgen-sensitive and castration-resistant prostate cancer (CRPC) models. Proteomic analysis of androgen-resistant prostate cells overexpressing DPP4 identified the involvement of the cellular adhesion molecules pathway. In prostate cells, lentiviral-mediated DPP4 overexpression restored androgen receptor signaling, inhibited epithelial-to-mesenchymal transition, and reduced cell migration, whereas DPP4 silencing produced the opposite effects. We demonstrate that DPP4 expression is down-regulated in CRPC cells and that treatment with capsaicin (CAP), a bioactive compound derived from red peppers, restores DPP4 expression. Moreover, DPP4 restoration by CAP suppresses prostate tumorigenesis in the TRAMP mice in vivo model of prostate cancer. Our results suggest that DPP4 could be a new target for CRPC.

Male↗

PubMed2026

In vivo genome-wide CRISPR screens identify FOXR1 as a suppressor of CD8+ T cell antitumor immunity.

T cell dysfunction critically limits the efficacy of T cell-based immunotherapies in solid tumors, yet the intrinsic regulators of T cell dysfunction remain incompletely understood. Through an in vivo genome-wide CRISPR screen in tumor-infiltrating CD8+ T cells, we identified Forkhead Box R1 (FOXR1) as a potent transcriptional suppressor of CD8+ T cell effector functions. Genetic ablation of FOXR1 significantly enhanced cytokine production and cytotoxic capacity in both murine and human CD8+ T cells, whereas its overexpression impaired T cell activation and effector molecule expression. Mechanistically, multiomics integration of RNA-seq, CUT&Tag-seq, and ATAC-seq revealed that FOXR1 binds directly to promoter regions of key effector genes, including IL2, GZMB, and PRF1, and represses their expression. Importantly, FOXR1 deletion in human anti-CD19 CAR T cells improved their efficacy against solid tumors, demonstrating that FOXR1 is a checkpoint of T cell effector function and targeting FOXR1 is a promising strategy to enhance CAR T cell efficacy against solid tumors.

Animals↗

PubMed2026

Changes in ACL T2* Metrics Over the Course of the Female Menstrual Cycle: A New Biomarker for the ACL Injury Risk?

BACKGROUND: Sex-based disparities in the anterior cruciate ligament (ACL) injury risk may be partly explained by cyclic variations in sex hormones that drive systemic shifts in tissue osmoregulation. Ultrashort echo time (UTE) T2* magnetic resonance imaging provides a noninvasive, quantitative means of evaluating the water content and collagen orientation in tissue. HYPOTHESIS: Eumenorrheic female participants will exhibit significant ACL T2* changes across the cycle, while anovulatory control participants will demonstrate no significant changes over time. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 25 women with no prior knee injuries were enrolled: 10 premenopausal, eumenorrheic participants and 15 anovulatory control participants (6 postmenopausal and 9 premenopausal using oral contraceptives). Bilateral knee magnetic resonance imaging was performed at 4 time points evenly spaced over 1 month, with the first visit within 24 hours of menses onset. Ovulation status was confirmed using commercially available ovulation predictor kits. Three-dimensional UTE sequences (11 echoes; 0.03-25 ms) were acquired to evaluate bicomponent ACL T2* metrics. Linear mixed-effects models assessed temporal differences in long and short T2* values, and the Cohen d quantified effect size. RESULTS: Eumenorrheic participants demonstrated significantly shorter preovulatory long T2* values compared with postovulatory values (mean difference, 1.0 ms [95% CI, 0.2-1.9 ms]; P = .015; Cohen d = 0.51). No significant temporal differences were observed for any T2* metric in anovulatory controls. CONCLUSION: Eumenorrheic female participants exhibited significant preovulatory to postovulatory changes in ACL T2* metrics, while anovulatory controls demonstrated no significant changes over time. These findings suggest that ACL T2* metrics are sensitive to cyclic fluctuations in female sex hormones across the menstrual cycle.

Humans↗

PubMed2026

Orbital involvement in sickle cell disease: A systematic review.

Orbital involvement in sickle cell disease (SCD) is rare but potentially vision-threatening and is often misdiagnosed due to overlap with infectious orbital disease. We conducted a systematic review of case reports and series describing orbital complications in patients with confirmed SCD, following PRISMA and MOOSE guidelines. Across 53 studies, 76 cases were identified. Patients were predominantly male (77.6%), with an average age of 13.2 years. Orbital disease was the initial SCD manifestation in 6.6%. Presentations included periorbital edema in all, proptosis in 64.1%, restricted ocular motility in 56.5%, reduced visual acuity in 28.1%, and bilateral involvement in 38.2%. Laboratory findings commonly included leukocytosis (73%) and raised inflammatory markers (86.7%). Radiologically, orbital subperiosteal hematoma were observed in 70%, combined orbital bone infarction and hematoma in 38.2%, and orbital bone infarction alone in 19.7%. Magnetic resonance imaging is critical for accurate diagnosis. Intracranial hemorrhage was present in 9.2%. Less frequent manifestations included orbital apex syndrome, lacrimal gland disease, and nonspecific soft tissue swelling. Management was primarily conservative (82.9%), and surgery was reserved for vision-threatening or intracranial complications. Complete recovery was achieved in 93.1% of cases. While severe vision-threatening complications are uncommon, early recognition remains critical to optimising outcomes in sickle cell orbitopathy.

Humans↗

PubMed2026

Targeting TP53 in triple-negative breast cancer: Molecular pathogenesis, therapeutic implications, and emerging pharmacological strategies.

Triple-negative breast cancer (TNBC) remains a highly aggressive and therapeutically challenging subtype, defined by the absence of oestrogen, progesterone, and HER2 expression. Tumour Protein 53 (TP53) mutations represent the most frequent genetic alteration, occurring in over 80% of cases and driving tumour initiation, progression, and therapeutic resistance. Mutant p53 proteins not only lose canonical tumour-suppressive functions but also often acquire gain-of-function (GOF) oncogenic properties that promote metastasis, genomic instability, and resistance to mechanisms like ferroptosis. This review examines the biological role of TP53 in TNBC pathogenesis and evaluates emerging pharmacological strategies aimed at targeting these vulnerabilities. Key approaches include the pharmacological reactivation of mutant p53 using small molecules such as APR-246, COTI-2, and the mutation-specific reactivator rezatapopt (PC14586), which has shown significant clinical tumour reduction in Y220C-mutant patients. Other strategies involve targeted protein degradation, the exploitation of synthetic lethal interactions (e.g., Chk1 or Aurora kinase B inhibition), and the use of natural products like cryptolepine or piperine derivatives. Recent clinical evidence further highlights the potential of combining epigenetic agents like decitabine with chemotherapy in TP53-mutant populations. Integrating TP53 mutation status into biomarker-driven treatment paradigms is a pivotal step toward achieving precision oncology and improving clinical outcomes for patients with TNBC.

Precision oncology↗

PubMed2026

Higher Rates of PASS and SCB After Arthroscopic Subspine Decompression Are Associated With a Positive Diagnostic AIIS Injection: A Propensity Score-Matched Cohort Study.

BACKGROUND: Hip arthroscopy effectively treats femoroacetabular impingement syndrome (FAIS), but persistent pain may be related to concomitant extra-articular pathology such as subspine impingement syndrome (SSI). Standard diagnosis of SSI often relies on 3-dimensional computed tomography (3D-CT) morphology (Hetsroni type II/III), although this morphology is common in individuals who are asymptomatic and correlates poorly with symptoms. PURPOSE: To compare minimum 2-year clinical outcomes after arthroscopic subspine decompression in patients with concurrent FAIS and type II/III anterior inferior iliac spine (AIIS) morphology, stratified by diagnostic method: 3D-CT morphology alone versus 3D-CT morphology plus a positive ultrasound-guided diagnostic injection. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study included patients aged 18 to 55 years with type II/III AIIS morphology who underwent primary hip arthroscopy for FAIS and SSI between January 2021 and November 2023 and had minimum 2-year follow-up. Patients diagnosed by CT morphology alone (CT classification group) were propensity score matched 1:1 to patients with a positive ultrasound-guided AIIS injection (injection group), with 57 patients per group. Matching variables were age, sex, body mass index, lateral center-edge angle, alpha angle, Tönnis grade, and Beighton score. All patients underwent arthroscopic subspine decompression. Patient-reported outcomes and rates of achieving the minimal clinically important difference, Patient Acceptable Symptom State (PASS), and substantial clinical benefit (SCB) were compared. RESULTS: Preoperative patient-reported outcome scores were similar between groups (all P > .05). At minimum 2-year follow-up, the injection group had significantly better scores on the modified Harris Hip Score (90.8 vs 84.2), Hip Outcome Score-Activities of Daily Living (88.4 vs 82.4), Hip Outcome Score-Sports Subscale (71.9 vs 64.1), 12-item International Hip Outcome Tool (83.9 vs 76.1), and visual analog scale for pain (1.2 vs 2.0) (all P < .001). Minimal clinically important difference rates were high in both groups, with higher rates in the injection group for modified Harris Hip Score (93% vs 77%; P = .033) and Hip Outcome Score-Activities of Daily Living (91% vs 75%; P = .042). PASS and SCB rates were significantly higher in the injection group across all patient-reported outcome measures (all P < .05). Revision and complication rates were low and did not differ significantly between groups. CONCLUSION: Both groups improved significantly after arthroscopic subspine decompression. However, patients with a positive ultrasound-guided diagnostic AIIS injection achieved higher PASS and SCB rates than those selected by CT morphology alone, suggesting that injection-confirmed SSI may improve patient selection for subspine decompression.

Humans↗

PubMed2026

Mitigating pH-induced instability in deruxtecan-based ADCs: an onboard-mixing icIEF approach for robust charge heterogeneity characterization.

Accurate charge variant analysis of antibody-drug conjugates (ADCs) is essential for understanding product heterogeneity and ensuring quality control. However, Deruxtecan (DXd)-based ADCs present a unique analytical challenge due to the intrinsic instability of the payload, where the lactone ring readily undergoes hydrolysis under alkaline conditions, resulting in time-dependent shifts in charge distribution during imaged capillary isoelectric focusing (icIEF). In this study, we describe the development of an onboard-mixing icIEF method designed to minimize pH-induced degradation during sample preparation. By separating ADC samples from carrier ampholytes (CAs) prior to injection and enabling real-time mixing within the instrument, this approach effectively suppresses premature lactone ring opening and stabilizes charge variant profiles. Comparative studies between conventional premixing and onboard-mixing approach demonstrated that the latter significantly enhances reproducibility, particularly for acidic variants that are highly sensitive to structural conversion. Comprehensive method validation confirmed excellent precision, linearity, and sensitivity, with consistent performance across run-to-run and intra-day analyses. The results underscore the importance of controlling microenvironmental pH exposure in the analysis of chemically instable ADCs. The proposed onboard-mixing strategy provides a robust and efficient solution for icIEF-based characterization, reducing analytical artifacts while simplifying method development. This approach is broadly applicable to ADCs and other biotherapeutics containing pH-sensitive functional groups.

Hydrogen-Ion Concentration↗

PubMed2026

Treatment-related associations of nucleus accumbens connectivity within mesocorticolimbic circuits in depression.

Pharmacological treatment remains a mainstay in managing depression, yet the neural correlates associated with treatment response remain incompletely understood. This study used multimodal neuroimaging to examine nucleus accumbens (NAc)-centered structural and functional alterations associated with fluoxetine and Shugan Jieyu Capsule (SG), a traditional Chinese medicine, in patients with mild-to-moderate depression (MMD). Sixty patients were randomized to an 8-week course of fluoxetine or SG. Depression severity was assessed using the 24-item Hamilton Depression Rating Scale (HAMD-24), and structural and functional MRI scans were acquired at baseline and endpoint. Both treatments were associated with significant symptom improvement. Neuroimaging analyses revealed structural and functional alterations involving the NAc. Changes in NAc-amygdala connectivity showed an exploratory association with symptom improvement in the SG group, whereas changes in NAc-rostral anterior cingulate cortex connectivity were associated with symptom improvement in the fluoxetine group and remained significant after correction for multiple comparisons. In addition, remitters exhibited stronger baseline connectivity between the NAc and ventral tegmental area and between the NAc and middle frontal gyrus compared with non-remitters. These findings suggest that NAc-centered connectivity may be relevant to treatment-related neural changes in depression and may inform future research on imaging-based candidate markers of treatment response and personalized treatment approaches. TRIAL REGISTRATION: The study is registered in https://www.chictr.org.cn/ with a registration number ChiCTR1900024988 (date: 08.06.2019).

Humans↗

PubMed2026

MRI-Negative Posterior Reversible Encephalopathy Syndrome: Comparison of Hypertensive Encephalopathy With and Without Vasogenic Edema.

OBJECTIVE: To explore whether posterior reversible encephalopathy syndrome (PRES) can present with negative magnetic resonance imaging (MRI) by comparing clinical features between cases of PRES with vasogenic edema and cases of hypertensive encephalopathy without MRI changes. PATIENTS AND METHODS: Patients diagnosed with hypertensive encephalopathy from August 1, 2008, to December 31, 2017, were identified retrospectively and matched by age (±5 years) and sex in a 1:2 ratio to patients retrospectively identified as having PRES from January 1, 2002, to November 30, 2017. A review of MRI images and clinical information was performed. RESULTS: We identified 16 cases of hypertensive encephalopathy and 32 age- and sex-matched controls with PRES showing vasogenic edema on MRI. There were no statistically significant differences in the odds of presentation with headache (odds ratio [OR], 1.372; 95% CI, 0.458 to 4.106), encephalopathy (OR, 2.303; 95% CI, 0.433 to 12.236), visual disturbance (OR, 0.826; 95% CI, 0.185 to 3.697), or focal neurologic deficit (OR, 4.000; 95% CI, 0.767 to 20.872). Seizures were more common in patients with vasogenic edema (OR, 0.082; 95% CI, 0.010 to 0.664). There were no significant differences in odds of acute kidney injury (OR, 2.90; 95% CI, 0.679 to 12.449) or odds of having a history of malignancy (OR, 0.295; 95% CI, 0.076 to 1.152), transplantation (OR, 3.347; 95% CI, 0.594 to 18.880), or autoimmune disease (OR, 0.400; 95% CI, 0.104 to 1.532). Systolic blood pressure at presentation was higher in patients with hypertensive encephalopathy and negative MRI as compared with patients with PRES and vasogenic edema (OR, 1.03; 95% CI, 1.01 to 1.05). CONCLUSION: Most presenting symptoms and risk factors were not significantly different between cases of hypertensive encephalopathy with and without vasogenic edema, arguing that the diagnosis of PRES in the setting of acute severe hypertension may not depend on MRI confirmation.

Humans↗

PubMed2026

Failure modes and effects analysis for clinical implementation of online adaptive radiotherapy: A systematic review.

BACKGROUND: The accuracy of radiotherapy is limited by anatomical variations occurring over time scales ranging from sub-seconds to days. Online Adaptive Radiotherapy (OART) addresses this by enabling daily plan adaptation based on real-time imaging. While OART offers improved dose conformity, its dynamic, time-constrained workflow introduces novel failure modes that challenge traditional quality assurance protocols. PURPOSE: This study aims to synthesize the existing literature on Failure Modes and Effects Analysis (FMEA) for OART to systematically catalog risks and identify mitigation strategies. METHODS: A systematic literature search was conducted to identify studies applying FMEA to OART workflows. Eleven studies were included, covering MR-guided (ViewRay MRIdian, Elekta Unity), CBCT-guided (Varian Ethos), and MR-enhanced C-arm linac systems. To address heterogeneity in risk scoring methodologies (e.g., TG-100 10-point scales vs. 5-point rankings), extracted failure modes were harmonized into a standardized three-tier risk classification system (Class I: Low, Class II: Intermediate, Class III: High). RESULTS: A total of 300 unique failure modes were identified, with 49.6 percent classified as high-risk (Class III). Analysis revealed that the majority of high-risk failures were concentrated in the online treatment delivery phase, specifically within human-computer interactions and anatomical contouring steps. CONCLUSIONS: This study supports the development of tailored, robust QA frameworks that prioritize human factors and process consistency to guide safe implementation in diverse clinical settings.

Humans↗

PubMed2026

AI echo INSIGHT study: A prospective blinded randomized trial of artificial intelligence echocardiogram interpretation.

BACKGROUND: Transthoracic echocardiography (TTE) is the most commonly performed cardiac imaging modality with over 30 million studies annually. Demand for timely expert interpretation continues to outpace capacity, creating diagnostic delays and inter-observer variability that impact patient care. Recent research has suggested computer vision artificial intelligence (AI) models can generate accurate preliminary comprehensive TTE reports, however, prospective evaluation is needed to determine whether AI-assisted TTE interpretation can improve clinician efficiency while preserving diagnostic accuracy. METHODS: AI ECHO INSIGHT is a prospective randomized blinded clinical trial conducted at Kaiser Permanente Northern California that will evaluate 1200 historical TTE studies (1000 consecutive unselected studies plus 200 with moderate or greater valvular disease) interpreted using three workflows: (1) AI-generated preliminary report finalized by a blinded cardiologist (AI-assisted); (2) cardiologist-generated preliminary report finalized by a blinded cardiologist (cardiologist-assisted); and (3) sonographer-generated preliminary report finalized by a blinded cardiologist (sonographer-assisted). The primary outcome is the rate of substantial change between preliminary and final reports, comparing the AI-assisted workflow to the pooled cardiologist-assisted and sonographer-assisted workflows. Secondary outcomes include cardiologist interpretation time for report finalization, superiority testing for diagnostic accuracy, and reporting consistency. CONCLUSION: AI ECHO INSIGHT is a prospective randomized blinded clinical trial evaluating the clinical impact of AI-assisted TTE interpretation on diagnostic accuracy, cardiologist efficiency, and reporting consistency in real-world echocardiography workflows. TRIAL REGISTRATION: ClinicalTrials.gov registration number NCT07229300.

Humans↗

PubMed2026

Divergent evolutionary strategies in spider venoms: A comparative proteomic profiling of four sympatric species from Yunnan.

Spider venoms comprise complex cocktails of bioactive molecules evolved for predation and defense, representing a valuable resource for biological research and pharmaceutical discovery. In this study, we performed a systematic analysis of venom gland extracts from four common spider species indigenous to Yunnan, China: Agelena limbata, Hippasa lycosina, Lycosa grahami, and Sinopoda pengi. Using an integrated transcriptomic and proteomic targeted profiling approach, we successfully annotated 141 distinct toxins. Comparative analysis revealed significant interspecific heterogeneity, suggesting distinct evolutionary trajectories and "weapon system economics." Both A. limbata and L. grahami exhibited a "peptide-dominant" profile anchored by neurotoxic peptides and isomerases, optimized for rapid chemical paralysis. In contrast, S. pengi displayed a distinct "protein-dominant" signature enriched with high-molecular-weight enzymes and CAP superfamily proteins, likely functioning to facilitate tissue degradation and toxin diffusion. Occupying an intermediate position, H. lycosina demonstrated a hybrid composition. These findings suggest that although these species share the same geographical range, their venom systems have undergone divergent evolutionary adaptations driven by specific ecological niches and hunting strategies. This study represents the first systematic proteomic characterization of these venom components, providing a valuable reservoir of molecular candidates while highlighting the bioinformatic nuances of analyzing whole-gland homogenates.

Animals↗

PubMed2026

The interplay between circadian misalignment or sleep disturbances and cognition and brain function in individuals with different degrees of insulin resistance - a systematic review.

Disruption of sleep increases the risk of type 2 diabetes and worsens cognitive outcomes, yet few studies have evaluated the interaction between insulin resistance and sleep parameters in relation to cognitive outcomes or the risk of dementia. This systematic review examines how circadian misalignment and sleep disturbances affect cognition and neuroimaging findings in individuals with varying degrees of insulin resistance. Across 27 studies, disrupted circadian rhythmicity and sleep disturbances were negatively associated with brain health, possibly through its effects on insulin sensitivity, whereas the impact of sleep duration and quality were inconclusive. Methodological heterogeneity, reliance on cross-sectional designs, and limited control for confounders restricted definitive conclusions and highlighted the need for longitudinal and interventional studies with objective measurements. Nonetheless, the findings support circadian rhythmicity as a potentially modifiable risk factor for preserving cognition in insulin-resistant populations. Future research should prioritise prospective and interventional studies and focus on biological markers rather than self-reported outcomes.

Humans↗

PubMed2026

Brain network alterations underlying cue reactivity and craving in abstinent methamphetamine users: a systematic review of functional MRI findings.

BACKGROUND: Methamphetamine use disorder (MUD) is marked by intense craving and high relapse risk, often triggered by drug-related cues. Functional magnetic resonance imaging (fMRI) provides key insight into the neural basis of this cue reactivity, implicating large-scale brain networks for reward, motivation, and control. Yet, findings remain inconsistent across studies due to differences in task design, abstinence duration, and participant characteristics. OBJECTIVE: This systematic review synthesises evidence on how abstinence influences brain network alterations underlying cue reactivity and craving in methamphetamine users, integrating task-based and resting-state fMRI findings within leading neurobiological models of addiction. METHODS: A systematic search of PubMed, Scopus, Web of Science, and Ovid was conducted up to August 10, 2025, following PRISMA 2020 guidelines. Eligible fMRI studies examined cue reactivity or craving in abstinent methamphetamine users. Data were extracted on activation, connectivity, and brain-behaviour associations, and synthesised narratively. RESULTS: Task-based studies revealed heightened activation across reward, salience, and control networks during cue exposure, which diminished as parietal and executive control systems re-engaged with longer abstinence. Resting-state findings showed disrupted intrinsic connectivity among default mode, salience, and frontoparietal networks, reflecting persistent imbalances linked to craving and use severity. CONCLUSION: fMRI evidence shows that MUD is marked by network-level disruption linking reward, salience, and control systems. Task-based findings reveal strong cue reactivity in reward circuits, while resting-state data show persistent imbalance among default mode and control networks. With abstinence, partial restoration of network integrity emerges, highlighting both vulnerability and opportunities for targeted, recovery-based interventions.

Humans↗

PubMed2026

Engineering bubble structures as Cas12a activators for highly sensitive monitoring of WRN helicase function.

The Werner syndrome helicase (WRN) is a critical synthetic lethal target in microsatellite instability cancers, essential for resolving complex genomic structures like replication bubbles and R-loops. However, strategies to simultaneously discriminate WRN activity on DNA versus DNA-RNA substrates in living cells are lacking. Here, we developed a structure-specific CRISPR/Cas12a biosensing strategy to visualize WRN functional activity by engineering bubble-structure probes. These probes were rationally designed to structurally mimic DNA replication bubbles and R-loop associated DNA-RNA hybrids. Upon specific unwinding by WRN, the probes release a sequestered activator strand that triggers Cas12a trans-cleavage, effectively converting the unwinding event into an amplified fluorescent signal. This assay achieves low picomolar sensitivity (LODs: 5.6-6.0 pM) and exceptional selectivity against homologous RecQ helicases. Uniquely, this strategy enables the parallel quantification of WRN activity on both substrate types, providing insights into distinct WRN-mediated pathways for resolving genomic stress. We further demonstrated the strategy's utility by visualizing endogenous WRN dynamics in living cells and profiling the efficacy of small-molecule inhibitors. This work offers a powerful molecular toolkit for dissecting WRN biology and facilitating high-throughput drug screening in targeted cancer therapy.

Werner Syndrome Helicase↗

PubMed2026

Volumetric bone marrow cellularity (VBMC) assessment from routinely processed trephines using three-dimensional x-ray histology and gaussian peak modelling.

Objective.Bone marrow cellularity is routinely estimated from a small number of two-dimensional histology sections, making assessment sensitive to section representativeness, processing artefacts and observer interpretation. Three-dimensional (3D) x-ray histology (XRH), using x-ray computed microtomography (µCT), enables non-destructive whole-block imaging of trephine biopsies. This study evaluated whether XRH combined with Gaussian peak modelling could provide a pragmatic whole-block volumetric bone marrow cellularity (VBMC) estimate from formalin-fixed paraffin-embedded (FFPE) trephine biopsy blocks.Approach.Six routinely processed FFPE bone marrow trephine blocks were imaged using µCT-based XRH at ∼15 µm spatial resolution. VBMC was defined as the red-marrow (RM) fraction of the marrow soft-tissue compartment, RM/(RM + intra-biopsy wax), with wax serving as the volumetric proxy for adipocyte/yellow marrow space. Whole-volume greyscale histograms were modelled using a three-peak Gaussian approach representing intra-biopsy wax, RM and demineralised trabecular matrix. Peak-height and area-under-the-curve metrics were compared with whole-volume 3D segmentation and clinical two-dimensional (2D) cellularity estimates.Main Results.Gaussian peak modelling successfully approximated the segmented tissue-phase distributions. The peak-height-derived VBMC metric showed the closest agreement with whole-volume 3D segmentation, with an average absolute percentage difference of 9.3%, compared with 18.6% for clinical expert 2D cellularity estimates. The area-under-the-curve metric followed similar trends but consistently overestimated VBMC. Clinical 2D cellularity broadly followed whole-biopsy trends but showed one discordant case not explained by slice-position sampling alone. XRH also enabled unrestricted virtual reslicing and visualisation of sectioning-associated artefacts prior to further microtomy.Significance.Pre-sectioning XRH combined with Gaussian peak modelling provides a rapid, segmentation-free route to volumetric cellularity estimation from intact clinical FFPE trephine blocks. The approach supports objective whole-biopsy assessment while remaining compatible with routine histopathology workflows, reflecting the expected limitations of section-based visual estimation despite its role as the current clinical standard. In the near term, it could provide a non-disruptive adjunct to conventional 2D cellularity reporting, pending larger validation studies.

Imaging, Three-Dimensional↗