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Open-Access 3D Bone Shape Databases in Orthopedics:An Unmet Need?
No full textObjective: 3D bone shapes play a critical role in preclinical and clinical orthopedic applications. This study aimed to identify and evaluate 10 most relevant existing online CT databases to see if they meet requirements of biomedical experts.Method: We performed a systematic search to identify relevant online CT databases for lower extremities. Additionally, a workshop with n=40 biomedical experts was held to gather insights on the benefits, challenges, and users for an online 3D bone shape database. This information was used to establish criteria to evaluate the identified databases.Results: We found that currently available online databases inadequately address experts’ needs, particularly regarding inclusion of different shape formats, such as 3D meshes and CAD models, and inclusion of mechanical properties of bones.Conclusion: These findings highlight a significant gap between databases’ offerings and users’ needs, underscoring the need for more comprehensive, accessible resources and advanced tools to support the field's progression.<br/
Sex-stratified osteochondral organ-on-chip model reveals sex-specific responses to inflammatory stimulation
No full textOsteoarthritis (OA) is a musculoskeletal degenerative disease characterized by alterations in cartilage and subchondral bone leading to impaired joint function. OA disproportionally affects females more than males, yet the molecular mechanisms underlying these biological sex differences remain elusive. Current therapeutic strategies to halt the progression of OA are still lacking, in part due to the limited predictive potential of standard models which often do not account for sex disparities. Herein, an organ-on-chip microfluidic platform was developed to model the osteochondral unit, composed of adjacent bone and cartilage culture chambers, and capture sex-specific hallmarks of OA. Sex-stratified human primary chondrocytes and osteoblasts were compartmentalized within biomimetic hydrogels emulating the bone-cartilage interface, which were subjected to inflammatory triggers to mimic the onset of OA. We confirmed that interleukin-1β and Tumor Necrosis Factor-α stimulation triggered upregulation of pro-inflammatory cytokines and matrix metalloproteinases related genes in all donors, with marginal trends for increased expression in female cells. In addition, metabolic labeling coupled with confocal imaging revealed that inflammatory stimulation modulated extracellular matrix deposition by human chondrocytes in a sex-specific fashion. Not only matrix deposition but also matrix remodeling was altered upon inflammation, leading to a significant reduction in matrix stiffness in both cartilage and bone compartments. Overall, sex-stratified osteochondral unit on-chips offer novel insights into sex-specific cellular responses to inflammatory insults, demonstrating the importance of incorporating sex stratification in emergent organ-on-chip models. Thus, this platform provides a physiologically relevant 3D microenvironment to further investigate sex-specific drivers of OA, paving the way for targeted therapies.</p
COVID-19 and water, sanitation and hygiene in schools:Implications, challenges, solutions
Get PDFIn an attempt to contain the spread of COVID-19, governments around the world temporarily closed educational institutions. These closures have impacted children and all school stakeholders, including school employees and students' families. Therefore, safely reopening schools so that children can return to a “normal” life and learning environment is crucial. However, schools in many low- and middle-income countries (LMICs) lack the necessary water, sanitation, and hygiene (WASH) infrastructure to ensure a safe reopening. Brazil, a global COVID-19 hotspot, has consistently struggled to implement a national response plan against SARS-CoV-2, including the safe reopening of schools. The provision of WASH in schools is essential not only to contain the spread of COVID-19 but also to prevent the transmission of various other WASH-related infectious diseases, such as soil-transmitted helminth infections, schistosomiasis, diarrhoea, cholera, and other gastrointestinal diseases. Ensuring the safe reopening of schools in Brazil and other LMICs is a short- and medium-term investment in enabling students to continue their studies during the ongoing crisis and a long-term investment in sustainable learning and the prevention of future outbreaks. This thesis aims to describe WASH conditions in schools in Brazil during the COVID-19 pandemic and identify possible barriers, enablers, and solutions related to WASH from the perspective of different school stakeholders.A mixed-methods approach with a partially mixed sequential equal status design was employed, comprising four phases: (i) a systematic literature review, (ii) quantitative analysis of secondary data, (iii) qualitative analysis of secondary data, and (iv) qualitative empirical field research. First, a systematic review was performed to (i) describe the current situation of WASH conditions in schools in LMICs and (ii) understand the implications of these conditions for the safe reopening of schools amidst the COVID-19 pandemic. Sixty-five of 6,287 publications identified in MEDLINE (via PubMed), Web of Science, Scopus, AJOL, and LILACS met the inclusion criteria. Data from 18,465 schools across 30 countries were extracted and analyzed according to the Joint Monitoring Programme (JMP) definitions and the normative contents of Human Rights to safe drinking water and sanitation. The systematic review established a baseline of WASH in schools in LMICs, highlighting how the Human Rights to Safe Drinking Water and Sanitation (HRtWS) are reflected in the learning environment and identifying key elements that require heightened focus to realize this fundamental human right. Findings indicate violations of all the contents of the HRtWS. In the context of the COVID-19 pandemic, results showed that the largely insufficient and inadequate school infrastructure hampers students' ability to practice healthy hygiene habits, particularly handwashing. Considering the paucity of data and research on WASH in schools in Latin America and noting that Brazil has been among the top three countries with the highest number of cumulative cases and deaths related to COVID-19, coupled with logistical advantages, Brazil was chosen as the study area for the subsequent quantitative and qualitative analyses.Second, secondary data from the BNSC was analyzed to better understand (iii) the current situation of WASH in schools in Brazil and (iv) to what extent Brazilian schools have been making progress in providing WASH since the beginning of the COVID-19 pandemic. Results of this study, considering 173,700 schools, indicate that most schools in Brazil (as of 2021) have bathrooms, drinking water of suitable quality for human consumption, improved sanitation facilities, and solid waste collection. Nonetheless, findings highlight the urgent need for improvements in public schools, schools located in rural areas, and in the North and Northeast regions of the country. Schools particularly need changes in sanitation infrastructure and solid waste management within the WASH domains. For the comparison of WASH in schools pre- and peri-COVID-19 pandemic (2020 vs. 2021), 170,422 schools were analyzed. Mixed changes in the variables, with both improvements and deterioration, were observed in schools across all regions of the country. Schools in the South and Southeast regions presented the best WASH infrastructure for safe reopening, whereas schools in the North and Northeast regions were the least prepared.Third, a content analysis of an inventory of 66 public policies was performed to (v) describe the WASH solutions outlined in policies released at the federal, state, and capital city levels in Brazil during the COVID-19 pandemic for the safe reopening of schools and (vi) discuss their potential to enhance schools' capacity to remain operational during a new pandemic or outbreak. One hundred and fifty-nine solutions for reopening schools in Brazil amidst the COVID-19 pandemic, divided into five WASH domains and five population groups, were extracted. While most of the suggested measures had the potential to provide a cleaner and safer environment and thereby enhance schools' resilience, some recommendations did not comply with the principles of the HRtWS, the JMP service ladder and definitions, international guidelines for WASH and IPC in schools, and the Sphere minimum standards for humanitarian aid. Highly recommended suggestions included: (i) installing hand hygiene stations in open areas of the schools (outdoor areas); (ii) adapting water fountain stations to allow consumption via cups or bottles, with pedal-operated taps and devices such as sensors; (iii) integrating WASH and health principles into school books and curricula. Moving on from COVID-19 and following the proposed solutions, policymakers and schools can follow three different paths and outcomes: (i) not proceed with any further intervention, most likely resulting in school closures during the next pandemic; (ii) implement measures that violate the frameworks or are scientifically incorrect, leading to schools being open with a false impression of safety; (iii) implement a combination of hardware and software measures in accordance with the four proposed frameworks, allowing schools to remain open or only closed for a short period during future pandemics.Last, in January 2024, fieldwork was carried out in a small municipality located in the Southeast of Brazil to (vii) assess how WASH-friendly the schools in the study area are and for which stakeholders and (viii) identify what WASH measures were implemented in the schools during the COVID-19 pandemic and which have persisted until the present. Four different activities tailored to specific stakeholders were performed: (i) semi-structured interviews with school staff; (ii) semi-structured interviews with parents and/or legal guardians; (iii) on-the-spot observations in the schools; and (iv) art-based research with students. Several inconsistencies were identified when comparing primary findings with the information previously provided by the BNSC, including differences in the number of schools and levels of education offered, water sources, absence of bathrooms for people with disabilities or limited mobility, bathrooms with showers for students, and waste burning instead of solid waste collection. We observed a clear violation of all the normative contents of the HRtWS, which, in turn, were triggering and exposing students to incidents of violence such as bullying and verbal abuse. Regarding the WASH interventions implemented during COVID-19, there was a misalignment among stakeholders about which interventions are still in place. During school visits, we observed that these interventions did not persist.<br/
Challenges and opportunities in the harmonization of trigger models for Anticipatory Action:a multi-hazard and multi-agency perspective
Get PDFDisaster risk financing has seen a transformative approach through Anticipatory Action (AA), designed to reduce shock and impact of multiple hazards on vulnerable population. The core of AA relies on pre-agreed triggering mechanisms, that are built around impact-based forecasts (IBF) and tailored to local contexts, determining when, where, and what interventions are required. While numerous humanitarian actors have adopted AA in the recent years, they often work in silos, employing varying definitions, methodologies, and processes, which complicates and reduces opportunities for collaboration. Additionally, the lack of standardization and transparency in trigger models limits comparability and potential for scaling efforts effectively. The ECHO-funded project, led by the Regional Anticipatory Action Working Group (RAAWG) secretariat addresses these challenges by fostering dialogue and coordination among regional actors in Southern Africa. Through stakeholder engagement and technical assessment, the project seeks to harmonize AA trigger methodologies, by developing an inventory of existing frameworks and co-designing a knowledge management platform to enhance information sharing and operational alignment.Initial results highlight the diverse landscape of AA in the region. The project’s first phase assembled 43 anticipatory action frameworks spanning eight countries and seven hazards, uncovering a mix of hazard-based and impact-based triggers. Funding sources for these frameworks include multilateral mechanisms, pooled funds, and bilateral arrangements, reflecting the diversity of financial arrangements to support AA initiatives. Gaps were noted in accessing comprehensive technical details and past trigger activation data, which is now being addressed through targeted surveys and forms. Stakeholder interviews highlighted growing collaboration, but also the challenges that remain in navigating the various triggers and processes and accessing timely information through an integrated platform. A prototype knowledge management platform was developed and refined based on user feedback, aiming to improve transparency and coordination at both technical and operational levels. These characterizations and stakeholders’ insights highlight critical gaps, opportunities for harmonizing trigger methodologies, and pathways for cross-agency collaboration. Building on this work, future research will explore the global landscape of AA through systematic literature review, mapping the current frameworks, assessing the operational maturity and identifying challenges and opportunities for scaling up. These findings will provide a foundation to evaluate and align technical, operational and financial aspects of AA. <br/
Co-creating a trigger model for cholera anticipatory action in Cameroon
Get PDFAnticipatory action (AA) refers to actions taken by humanitarian actors and governments to reduce the humanitarian impacts of a forecasted hazard before it occurs. To date, most AA initiatives have focused on hydrometeorological events, but initiatives for in particular climate-sensitive diseases are gaining traction. Acting ahead of a disease outbreak or controlling an epidemic early on can significantly reduce the impacts. Cameroon has experienced recurrent cholera epidemics since 1971. The Cameroon Red Cross has been working with the French Red Cross, technical partners (510 an initiative of the Netherlands Red Cross and EHESP), and in-country actors such as the Ministry of Health to co-create an Early Action Protocol (EAP) for cholera. An EAP contains a model that triggers early actions once a certain forecast or observation reaches a threshold that indicates there could be severe negative impacts corresponding to a one-in-five-year return period. Cholera is a water-borne disease, where climatic, environmental, and socio-economic factors contribute to its risk. The development of a trigger model requires historical data on these factors, but this data is often difficult to obtain or not available with sufficient spatial and temporal resolution. Also, for an operational trigger model, the input data of the trigger model has to be available in near-real time. A data-sharing agreement with the Ministry of Health was put in place to get access to the sensitive cholera incidence data. Correlation analyses between daily rainfall (as floods impact WASH infrastructure) and cholera case data were done for delays between 7 to 14 days, as it is known from the literature that the first cholera cases usually occur after a few days of flooding. However, only very weak correlations were found. A moving average of rainfall over 50 mm/day for four consecutive days did correspond to a significant number of cholera cases. The trigger model proposed relies only on observed data and consists of two parts. Trigger 1 is a climatic trigger that triggers when a district experiences flooding with over 2000 people affected or when it experiences 4 days with an average daily rainfall of at least 50 mm. Trigger 2 goes off whenever at least 5 suspected cases or 1 confirmed cholera case are identified through community-based or national surveillance systems. To activate trigger 2, trigger 1 must already have been activated. The next steps will include gaining experience with activations with this protocol, while also, from a research point of view, evolving the trigger model once more data on the cholera risk factors becomes available
A shape completion model for corrective osteotomy of distal radius malunion
Get PDFPurpose When performing 3D planning for osteotomies in patients with distal radius malunion, the contralateral radius iscommonly used as a template for reconstruction. However, in approximately 10% of the cases, the contralateral radius is notsuitable for use. A shape completion model may provide an alternative by generating a healthy radius model based on theproximal part of the malunited bone. The aim of this study is to develop and clinically evaluate such a shape completionmodel.Method A total of 100 segmented CT scans of healthy radii were used, with 80 scans used to train a statistical shape model(SSM). This SSM formed the base for a shape completion model capable of predicting the distal 12% based on the proximal88%. Hyperparameters were optimized using 10 segmented 3D models, and the remaining 10 models were reserved for testingthe performance of the shape completion model.Results The shape completion model consistently produced clinically viable 3D reconstructions. The mean absolute errorsbetween the predicted and corresponding reference models in the rotational errors were 2.6 ± 1.7° for radial inclination, 3.6± 2.2° for volar tilt, and 2.6 ± 2.8° for axial rotation. Translational errors were 0.7 ± 0.6 mm in dorsal shift, 0.8 ± 0.5 mmin radial shift, and 1.7 ± 1.1 mm in lengthening.Conclusion This study successfully developed a shape completion model capable of reconstructing healthy 3D radius modelsbased on the proximal bone. The observed errors indicate that the model is viable for use in 3D planning for patients lackinga healthy contralateral radius. However, routine use in patients with a healthy contralateral radius is not yet advised, as errormargins exceed bilateral differences observed in healthy populations. The most clinically relevant error found in the model,length mismatch, can be easily corrected during 3D planning if the ipsilateral ulna remains intact
Glucose in acute ischemic stroke:Effects and options for monitoring and treatment
Get PDFIschemic stroke is a major cause of disability in developed countries. The only treatment to improve outcome consists of rapid recanalization by means of intravenous thrombolysis (IVT) or endovascular therapy (EVT). Hyperglycemia on admission is commonly observed in acute ischemic stroke patients and has been associated with unfavorable outcomes. Several studies have investigated the effects of actively lowering glucose in patients with acute ischemic stroke and hyperglycemia. These studies, however, have not shown any significant effect on infarct size or functional outcome. This lack of efficacy is probably related to insufficiently accurate glucose monitoring and insufficiently precise glucose-lowering.The aims of this thesis were to study the relation between hyperglycemia in the acute phase and outcomes of patients with acute ischemic stroke treated with EVT, to develop a more accurate approach for glucose monitoring during acute ischemic stroke, and to explore alternatives to insulin as a glucose-lowering therapy in these patients
Predicting Psychological States using Machine Learning and Digital Biomarkers from wearable data
Get PDFBackground: Prior research has shown that digital biomarkers can predict mental states associated with depression and anxiety. However, their ability to detect positive psychological states—such as positive emotions, meaning in life, self-esteem, and accomplishment—remains less explored. This pilot study aims to address this gap by investigating whether smartwatch-derived digital biomarkers can predict daily psychological states aligned with the PERMA framework (Positive Emotion, Engagement, Relationships, Meaning, and Accomplishment), providing a more comprehensive understanding of mental well-being.Methods: Thirty-four healthy volunteers wore research-grade smartwatches for eight consecutive days, enabling the passive collection of physiological signals, including heart rate variability (HRV), electrodermal activity (EDA), and actigraphy. Participants also completed end-of-day ecological momentary assessments measuring 18 PERMA-related psychological states. After data preprocessing, we extracted 177 features from actigraphy, HRV, and EDA. Principal component analysis (PCA) was applied to identify relevant feature subsets. Machine learning models—including Random Forest, Long Short-Term Memory (LSTM) networks, and Convolutional Neural Networks (CNNs)—were employed to predict psychological states from the complete feature set and the reduced subset. Classification performance was evaluated using three metrics: (1) prediction accuracy, (2) threshold accuracy (correct if within ±1 of the true label), and (3) top3 accuracy (true label among the top three predictions). Additionally, interpretable AI techniques identifiedthe most influential features, while conformal prediction assessed prediction uncertainties.Findings: While overall classification accuracy for PERMA-related psychological states was low across all models, the CNN-based model achieved a threshold accuracy of 62%, indicating that all predictions fell within ±1 of the true label. The LSTM model, when applied to PCA-extracted features, achieved the highest threshold accuracy of 60%. Performance analysis of individual psychological states revealed that self-esteem constructs had the highest prediction accuracy for both positive and negative emotions. Anger-related negative emotions also demonstrated strong accuracy, likely due to well-documented physiological responses associated with anger in prior research. Constructs related to meaning in life and personal relationships exhibited moderate accuracy, reflecting their complex cognitive and emotional components. Our findings demonstrated moderate explainability of daily psychological states, with actigraphy consistently emerging as the strongest predictor across different algorithms. These patterns held true even after accounting for physiological signals from HRV and EDA, highlighting the contribution of movement data. Movement patterns explained substantial variations in participants’ positive mental states, emphasizing the role of physical activity.Discussion: These findings suggest that wearable-derived biomarkers can effectively track fluctuations in positive psychological states in real-world settings. By integrating interpretable AI techniques and uncertainty quantification, wearable technology holds promise for personalized mental health monitoring and timely interventions. Future research should refine feature extraction methods and validate these results in larger, more diverse populations to enhance generalizability
The FAIR data point populator:collaborative FAIRification and population of FAIR data points
Get PDFBackground: Use of the FAIR principles (Findable, Accessible, Interoperable and Reusable) allows the rapidly growing number of biomedical datasets to be optimally (re)used. An important aspect of the FAIR principles is metadata. The FAIR Data Point specifications and reference implementation have been designed as an example on how to publish metadata according to the FAIR principles. Metadata can be added to a FAIR Data Point with the FDP’s web interface or through its API. However, these methods are either limited in scalability or only usable by users with a background in programming. We aim to provide a new tool for populating FDPs with metadata that addresses these limitations with the FAIR Data Point Populator. Results: The FAIR Data Point Populator consists of a GitHub workflow together with Excel templates that have tooltips, validation and documentation. The Excel templates are targeted towards non-technical users, and can be used collaboratively in online spreadsheet software. A more technical user then uses the GitHub workflow to read multiple entries in the Excel sheets, and transform it into machine readable metadata. This metadata is then automatically uploaded to a connected FAIR Data Point. We applied the FAIR Data Point Populator on the metadata of two datasets, and a patient registry. We were then able to run a query on the FAIR Data Point Index, in order to retrieve one of the datasets. Conclusion: The FAIR Data Point Populator addresses the limitations of the other metadata publication methods by allowing the bulk creation of metadata entries while remaining accessible for users without a background in programming. Additionally, it allows efficient collaboration. As a result of this, the barrier of entry for FAIRification is lower, which allows the creation of FAIR data by more people.</p
Pelvic Organ Prolapse Quantification After Pessary Removal:The Use of Upright MRI in POP Research
Get PDFIntroduction: When pelvic organ prolapse (POP) patients change from pessary to surgical treatment, new POP quantification is often necessary. However, the time to maximal POP recurrence after pessary removal is unclear. This video-article illustrates the variation over time of POP extent after pessary removal.Methods: Upright MRI scans of 12 POP patients were used to measure the distances from the lowest points of bladder and cervix to the Pelvic Inclination Correction System (PICS)) line, with the pessary in situ, immediately, 4 and 8 h after pessary removal. Statistical differences between time points were determined.Results: The bladder descended immediately after pessary removal from a median of 0.1 cm above to 1.8 cm below the PICS line. In 58% of patients, the bladder then remained stable; in 33%, the bladder further descended up to 5.4 cm after 4 to 8 h. The cervix descended immediately after pessary removal from a median of 3.1 cm to 1.9 cm above the PICS line. In 17% of patients, a late cervix descent after 4–8 h was seen.Conclusion: POP quantification should be delayed at least 8 h after pessary removal to prevent underestimation of POP extent.</p