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Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are powerful in vitro models to study the mechanisms underlying cardiomyopathies and cardiotoxicity. Quantification of the contractile function in single hiPSC-CMs at high-throughput and over time is essential to disentangle how cellular mechanisms affect heart function. Here, we present CONTRAX, an open-access, versatile, and streamlined pipeline for quantitative tracking of the contractile dynamics of single hiPSC-CMs over time. Three software modules enable: parameter-based identification of single hiPSC-CMs; automated video acquisition of >200 cells/hour; and contractility measurements via traction force microscopy. We analyze >4,500 hiPSC-CMs over time in the same cells under orthogonal conditions of culture media and substrate stiffnesses; +/- drug treatment; +/- cardiac mutations. Using undirected clustering, we reveal converging maturation patterns, quantifiable drug response to Mavacamten and significant deficiencies in hiPSC-CMs with disease mutations. CONTRAX empowers researchers with a potent quantitative approach to develop cardiac therapies.

Determining the pathogenicity of hypertrophic cardiomyopathy-associated mutations in the β-myosin heavy chain (MYH7) can be challenging due to its variable penetrance and clinical severity. This study investigates the early pathogenic effects of the incomplete-penetrant MYH7 G256E mutation on myosin function that may trigger pathogenic adaptations and hypertrophy. We hypothesized that the G256E mutation would alter myosin biomechanical function, leading to changes in cellular functions. We developed a collaborative pipeline to characterize myosin function across protein, myofibril, cell, and tissue levels to determine the multiscale effects on structure-function of the contractile apparatus and its implications for gene regulation and metabolic state. The G256E mutation disrupts the transducer region of the S1 head and reduces the fraction of myosin in the folded-back state by 33%, resulting in more myosin heads available for contraction. Myofibrils from gene-edited MYH7WT/G256E human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) exhibited greater and faster tension development. This hypercontractile phenotype persisted in single-cell hiPSC-CMs and engineered heart tissues. We demonstrated consistent hypercontractile myosin function as a primary consequence of the MYH7 G256E mutation across scales, highlighting the pathogenicity of this gene variant. Single-cell transcriptomic and metabolic profiling demonstrated upregulated mitochondrial genes and increased mitochondrial respiration, indicating early bioenergetic alterations. This work highlights the benefit of our multiscale platform to systematically evaluate the pathogenicity of gene variants at the protein and contractile organelle level and their early consequences on cellular and tissue function. We believe this platform can help elucidate the genotype-phenotype relationships underlying other genetic cardiovascular diseases.

Abstract Bladder cancer is the 10th most common and 13th most deadly cancer worldwide, with urothelial carcinomas being the most common type. Distinguishing between non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC) is essential due to significant differences in management and prognosis. MRI may play an important diagnostic role in this setting. The Vesical Imaging Reporting and Data System (VI-RADS), a multiparametric MRI (mpMRI)-based consensus reporting platform, allows for standardized preoperative muscle invasion assessment in BCa with proven diagnostic accuracy. However, post-treatment assessment using VI-RADS is challenging because of anatomical changes, especially in the interpretation of the muscle layer. MRI techniques that provide tumor tissue physiological information, including diffusion-weighted (DW)- and dynamic contrast-enhanced (DCE)-MRI, combined with derived quantitative imaging biomarkers (QIBs), may potentially overcome the limitations of BCa evaluation when predominantly focusing on anatomic changes at MRI, particularly in the therapy response setting. Delta-radiomics, which encompasses the assessment of changes (Δ) in image features extracted from mpMRI data, has the potential to monitor treatment response. In comparison to the current Response Evaluation Criteria in Solid Tumors (RECIST), QIBs and mpMRI-based radiomics, in combination with artificial intelligence (AI)-based image analysis, may potentially allow for earlier identification of therapy-induced tumor changes. This review provides an update on the potential of QIBs and mpMRI-based radiomics and discusses the future applications of AI in BCa management, particularly in assessing treatment response. Critical relevance statement Incorporating mpMRI-based quantitative imaging biomarkers, radiomics, and artificial intelligence into bladder cancer management has the potential to enhance treatment response assessment and prognosis prediction. Key Points Quantitative imaging biomarkers (QIBs) from mpMRI and radiomics can outperform RECIST for bladder cancer treatments. AI improves mpMRI segmentation and enhances radiomics feature extraction effectively. Predictive models integrate imaging biomarkers and clinical data using AI tools. Multicenter studies with strict criteria validate radiomics and QIBs clinically. Consistent mpMRI and AI applications need reliable validation in clinical practice. Graphical Abstract

Background: The Group Climate Inventory (GCI) was tested for measurement invariance across 332 adults with and 225 adults without mild intellectual disabilities in Dutch forensic treatment, and for latent mean differences on its "Support", "Growth", "Repression", and "Atmosphere" subscales. Method: Multigroup confirmatory factor analysis was used to evaluate the configural, threshold, and loading and threshold invariance of the GCI across both groups, and to compare group latent means on each subscale. Results: Measurement invariance was found across groups. Latent mean group comparisons showed small but significant differences reflected in lower scores on Support and Atmosphere in the group with mild intellectual disabilities. Conclusion: The GCI allows meaningful comparisons between clients with and without mild intellectual disabilities in secure facilities. Results from the between-group comparisons suggest that consideration should be given as to whether, and why, the support and atmosphere perceptions of clients with mild intellectual disabilities might be less good.

Background: In secure residential facilities, group climate perceptions of clients with mild intellectual disability or borderline intellectual functioning are systematically assessed for quality improvement. A valid and reliable measure may ensure that this process is consistent. The Group Climate Inventory--Revised (GCI-R) is a new measure to assess group climate perceptions. Method: Confirmatory factor analysis was conducted in 148 adult clients (79% male) with mild intellectual disability or borderline intellectual functioning in a secure facility to examine internal structure validity and internal consistency reliability of the GCI-R. Results: The results indicate support for the five-factor structure of the GCI-R ('Support', 'Growth', 'Repression', 'Peer interactions', and 'Physical environment'). The internal consistency reliability of its scales ranged from acceptable to good ([alpha]: 0.72-0.87; [omega]: 0.76-0.86). Conclusion: The GCI-R demonstrates evidence of psychometric adequacy when applied to adult clients with mild intellectual disability or borderline intellectual functioning in secure residential facilities.

Assessment and monitoring of safety in special education schools is imperative to establish and maintain a safe environment in which students can develop academic and social-emotional skills. The present study describes the development of a student self-report measure, the Safe at School questionnaire. Factorial validity, reliability and concurrent validity was examined in a construction sample of 280 students (68.6% male, age M = 13.29, SD = 2.52) and a validation sample of 1572 students (77.4% male; age M = 14.33, SD = 2.04), representing 233 classes from 20 schools for special education in the Netherlands. Multilevel confirmatory factor analysis was used to examine the factor structure of the Safe at School questionnaire. A model with three correlating factors at the within- and between-group level (Rules and Social Norms, Perceived Own Safety and Perceived Safety of Other Students) showed a satisfactory fit to the data. Reliabilities of the scales were good. Also, measurement invariance for gender was demonstrated, indicating no differences in latent means between boys and girls. Implications for practice and future research are discussed.

Variants in the gene myosin-binding protein C3 (MYBPC3) account for approximately 50% of familial hypertrophic cardiomyopathy (HCM), leading to reduced levels of myosin-binding protein C3 (MyBP-C), the protein product made by gene MYBPC3. Elucidation of the pathways that regulate MyBP-C protein homeostasis could uncover new therapeutic strategies. Toward this goal, we screened a library of 2,426 bioactive compounds and identified JG98, an allosteric modulator of heat shock protein 70 that inhibits interaction with Bcl-2-associated athanogene (BAG) domain co-chaperones. JG98 reduces MyBP-C protein levels. Furthermore, genetic reduction of BAG3 phenocopies treatment with JG-98 by reducing MYBP-C protein levels.. Thus, an unbiased compound screen identified the heat shock protein 70-BAG3 complex as a regulator of MyBP-C stability.

Background: Emicizumab, a bispecific antibody that mimics factor (F)VIII, has significantly improved hemophilia A management. Although emicizumab levels can be measured, tools for estimating the hemostatic efficacy of emicizumab are lacking. Thrombin generation (TG) assays can distinguish bleeding phenotypes in persons with hemophilia A on FVIII prophylaxis and may also be used during emicizumab therapy. Objectives: To assess the association between TG parameters, emicizumab levels, and bleeding in patients on emicizumab therapy. Methods: A single-center longitudinal cohort study was conducted, with samples collected during the steady-state phase of emicizumab therapy. TG was measured using tissue factor (TF; TF-TG, 1 pM) and FXIa (FXIa-TG, 200 pM). Emicizumab concentrations were determined with mass spectrometry. Only treated bleeds were recorded. Pearson correlations (rho, r) were reported. Results: Eighty-five samples from 49 patients were analyzed during a median of 1 year of emicizumab therapy. Most bleeds were traumatic (97%; n = 30), whereas 1 bleed was spontaneous. At 12 months, TF-TG (r = 0.42) showed a borderline correlation, and FXIa-TG (r = 0.15) showed no correlation with emicizumab concentrations. Although FXIa-TG showed a 9% higher endogenous thrombin potential in patients with zero vs ≥1 treated bleed (endogenous thrombin potential: 957 vs 878 nM/min, P = .045), neither the FXIa-peak height nor TF-TG showed any association with traumatic bleeding. Conclusion: TG parameters showed no clinically relevant correlations with emicizumab plasma concentrations, were not associated with traumatic bleeding, and showed considerable intrapatient variability. Therefore, TG was not considered useful for monitoring coagulation potential in patients on steady-state emicizumab prophylaxis.

Sleep cycles are defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. Fractal or aperiodic neural activity is a well-established marker of arousal and sleep stages measured using electroencephalography. We introduce a new concept of ‘fractal cycles’ of sleep, defined as a time interval during which time series of fractal activity descend to their local minimum and ascend to the next local maximum. We assess correlations between fractal and classical (i.e. non-REM – REM) sleep cycle durations and study cycles with skipped REM sleep. The sample comprised 205 healthy adults, 21 children and adolescents and 111 patients with depression. We found that fractal and classical cycle durations (89±34 vs 90±25 min) correlated positively (r=0.5, p

The effects of stony coral tissue loss disease (SCTLD) in the Dutch Caribbean, specifically in Bonaire, have not been documented since its first sighting in March 2023. By comparing the results of the 2023 surveys with data from previous surveys conducted over the past 9 years, this study quantifies the overall decline in coral cover and investigates the spatial variability of SCTLD’s impact across different subregions of the reef on the leeward side of Bonaire. In the year 2023, a crucial period in the initial phase of the progression of SCTLD, significant reduction in coral coverage was observed, with six key reef-building coral species showing significant vulnerability. Importantly, this research identifies specific subregions that have been disproportionately affected. The insights gained from this study are important for the potential development of specific conservation and restoration strategies for Bonaire, underscoring the necessity for ongoing ecosystem monitoring to safeguard the future of highly sensitive coral reefs in a changing ocean. By advancing our understanding of SCTLD dynamics, this research contributes to the global effort to preserve coral reef ecosystems in the face of emerging coral diseases.

Background Lymphatic disorders such as protein‐losing enteropathy, plastic bronchitis, and chylothorax are important complications of the Fontan circulation and ultimately result in an increased risk of early death. Several European centers are now performing lymphatic procedures. The aim of this study is to map the extent of these lymphatic disorders and treatments provided across European pediatric cardiology centers. Methods and Results A survey was circulated to 49 European pediatric cardiology centers consisting of 37 questions including a mix of binary, categorical, and continuous variables. Thirty‐one centers (63%) participated in the study, performing a median of 250 (interquartile range, 178 ‐ 313) cardiopulmonary bypass procedures per year. Chylothorax emerged as the most prevalent lymphatic disorder followed by protein‐losing enteropathy and plastic bronchitis. The most common diagnostic investigation method was noncontrast magnetic resonance lymphangiography (52%). Eleven centers (35%) conducted lymphatic interventions with a median of 3 (interquartile range, 1 ‐ 4) procedures per year and 12 (interquartile range, 5 ‐ 15) interventions in total per center. Conclusions This study confirms the rarity of and variation in treatment approaches for lymphatic disorders across Europe. With at least 11 centers offering lymphatic interventions, the adoption of these procedures is on the rise in Europe. To improve the quality of care and treatment outcomes for these complex patients, it is crucial to consider evidence‐based lymphatic diagnostics, interventional lymphatic procedures, and the centralization of services in Europe.

Background: Glycoprotein (GP)VI is a platelet-specific collagen receptor required for platelet activation during hemostasis. Platelet reactivity toward collagen is routinely assessed during diagnostic workup of platelet disorders. GPVI can be activated by inducing receptor clustering with suspensions of fibrillar collagen or synthetic cross-linked collagen-related peptide (CRP-XL). However, these suspensions are poorly standardized or difficult to produce. Nanobodies are small recombinant camelid-derived heavy-chain antibody variable regions. They are highly stable, specific, and ideal candidates for developing a stable GPVI agonist for diagnostic assays. Objectives: Develop a stable nanobody-based GPVI agonist. Methods: Nanobody D2 (NbD2) was produced as dimers and purified. Tetramers were generated via C-terminal fusion of dimers with click chemistry. Nanobody constructs were functionally characterized with light transmission aggregometry (LTA) in platelet-rich plasma and whole blood flow cytometry. Diagnostic performance was assessed in patients with inherited platelet function disorders with LTA and flow cytometry. Results: NbD2 was specific for human platelet GPVI. Dimers did not result in platelet activation in LTA or flow cytometry settings and fully inhibited CRP-XL-induced P-selectin expression and fibrinogen binding in whole blood and attenuated collagen-induced platelet aggregation in platelet-rich plasma. However, NbD2 tetramers caused full platelet aggregation, as well as P-selectin expression and fibrinogen binding. NbD2 tetramers were able to discriminate between inherited platelet function disorder patients and healthy controls based on fibrinogen binding, similar to CRP-XL. Conclusion: Nanobody tetramers to GPVI induce platelet activation and can be used to assess the GPVI pathway in diagnostic assays.