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Exercise echocardiography for risk stratification in unexplained dyspnea : the incremental value of the mean pulmonary artery pressure/slope
No full textAbstract: Background Patients with unexplained dyspnea and an elevated mean pulmonary artery pressure (mPAP)/cardiac output (CO) slope on invasive hemodynamic assessment during exercise have worse clinical outcomes. The aim of this study was to evaluate the incremental prognostic value of the noninvasive mPAP/CO slope in addition to heart failure with preserved ejection fraction (HFpEF) probability scores and diastolic stress testing in patients with unexplained dyspnea. Methods In a multicenter cohort study involving six Belgian dyspnea clinics, patients with unexplained dyspnea underwent exercise echocardiography for mPAP/CO slope assessment. Positive HFpEF scores were defined as HFA-PEFF (Heart Failure Association pretest probability echocardiography, functional testing, final diagnosis) score >= 5 and H2FPEF (heavy, hypertensive, atrial fibrillation, pulmonary hypertension, elder, filling pressure) score >= 6. The outcome evaluated was a composite of all-cause mortality or heart failure hospitalization. Results Among 2,452 patients (mean age, 63 +/- 15 years; 53% women), mPAP/CO slope > 3.5 mm Hg L-1 min(-1) best predicted adverse outcomes. The prognostic value of the mPAP/CO slope was greater in patients with negative HFpEF scores than in those with positive scores (interaction P = .02). The mPAP/CO slope remained independently prognostic after adjustment for N-terminal pro-B-type natriuretic peptide (hazard ratio [HR], 2.26; 95% CI, 1.33-3.82) and for HFpEF scores and diastolic stress testing (HR, 1.99; 95% CI, 1.37-2.88), whereas exercise tricuspid regurgitant velocity did not. Both HFpEF score-negative patients with slope > 3.5 mm Hg L-1 min(-1) (HR, 2.99; 95% CI, 1.81-4.95) and HFpEF score-positive patients (HR, 6.29; 95% CI, 4.25-9.31) showed significantly higher risk compared with HFpEF score-negative patients with slope L-1 min(-1). Conclusions The mPAP/CO slope, unlike exercise tricuspid regurgitant velocity, adds prognostic value beyond natriuretic peptides, HFpEF scores, and diastolic stress testing, identifying high-risk patients with exercise-induced hemodynamic abnormalities who may benefit from invasive confirmation and closer follow-up
A socio-legal examination of Belize's debt swap from a human rights perspective
No full textAbstract: This article examines the everyday impact of Belize\u2019s debt-for-ocean conservation swap on the right to an adequate standard of living for local fisheries households. Beyond reducing its short- to medium-term debt servicing obligations through the swap, Belize also entered contractual obligations to achieve marine conservation goals. This socio-legal study analyses two key implementation streams of these conservation commitments: the marine spatial planning process and the conservation trust fund. Drawing upon a literature review and 38 semi-structured interviews with stakeholders, the research focuses on Belize\u2019s fisheries households, a particularly vulnerable group recognized as the second most impoverished fishing community among CARICOM countries. While the Agreement\u2019s legal innovations and replicability is praised, this study finds that the legal terms and current implementation of conservation commitments exacerbate the lack of fisherfolk\u2019s access to the means and resources necessary for an adequate standard of living. The findings suggest that more democratic settings for contractual negotiations and conservation funding mechanisms are necessary if the instrumentalization of international economic law is to effectively advance environmental commitments
Advancing fish embryo tests for endocrine disruptor testing : assessing endocrine adversity in non-protected life stages
No full textSVEBI : towards the interpretation and explanation of spiking neural networks
No full textAbstract: Artificial Neural Networks have demonstrated the versatility to adapt to different problems while at the same time achieving high predictive performance. A characteristic of these models is their high-computation demands, which translates into high energy consumption. Spiking Neural Networks (SNN) have been proposed as an energyefficient alternative with promising results in several tasks. Despite being a promising alternative that could motivate massive deployment, research on the interpretation of these models is almost non-existent. To address this problem, we propose SVEBI, a method that extracts insights on the representation encoded by SNNs, via the analysis of sparse relevant internal units that drive the decision-making process. In addition, we show the use of the relevant units as a means to justify, i.e. explain, the predictions made by an SNN for a given input. In this explanation/ justification task, our experiments show SVEBI is comparable, if not superior, to existing methods
Assessment of common electrode placement methods for surface electromyography recordings of the triceps surae muscles
No full textAbstract: Introduction: In surface electromyography, optimal electrode placement is critical. Various techniques are available for placing the electrodes appropriately, yet these are rarely assessed for accuracy, especially for electrode placement away from neighboring muscles considering the large variation in individual muscle morphology. This study evaluated triceps surae electrode placement using SENIAM recommendations and expert palpation, relative to anatomical muscle boundaries. Methods: Electrodes were placed on the medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus of twenty-four participants following SENIAM guidelines and expert muscle palpation. Ultrasound was used to calculate the distances between electrodes and muscle boundaries at rest and during fixed-end plantar flexion at two intensities, in both plantar flexion and dorsiflexion positions. Results: SENIAM placed the electrodes laterally (electrode-boundary distance: 0.7 \ub1 0.9 cm) and the expert more centrally (distance to lateral boundary: 4.1 \ub1 0.9 cm; medial boundary: 3.0 \ub1 0.9 cm) on the LG. In four participants, SENIAM placements were positioned outside the LG muscle boundary. In soleus, SENIAM placements were close to the tibial border (0.7 \ub1 0.4 cm). For MG, both methods performed well. Conclusion: This study highlights limitations of the SENIAM placement protocol for the LG and soleus, and supports the use of individualized approaches to improve electrode accuracy and enhance the validity of EMG recordings
Development and validation of an LC-MS/MS method for the simultaneous detection of urinary inflammatory biomarkers in a Flemish birth cohort
No full textAbstract: Chronic inflammation is a significant contributor to various diseases but its assessment via blood sampling presents challenges, particularly in children. The evaluation of urinary biomarkers, including 3-bromotyrosine (Bty), 3-chlorotyrosine (Cty) and leukotriene E4 (LTE4), offers a non-invasive alternative. This study presents the optimization and validation of a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of Bty, Cty and LTE4 in urine. Under optimized conditions, sample preparation was based on SPE using Oasis MAX cartridges, followed by LC-MS/MS analysis. Method performance was validated using the ICH 10 guidelines, resulting in satisfactory results for all analytes in terms of recovery, linearity, limits of quantification, precision and accuracy. Recovery rates ranged from 82 % to 97 %, while matrix effects were observed within the range of 1211 % to 26 %. Linear range spanned from 0.08 to 20 ng/mL for the three analytes. Application to 332 urine samples from the ENVIRONAGE birth cohort (Belgium), comprising of children aged 4\u201311 years, revealed detection frequencies of 18 % for LTE4, 19 % for Cty and 50 % for Bty. Notably, creatinine-corrected Cty and LTE4 exhibited statistically significant Spearman correlations with established systemic inflammation markers. Specifically, Cty was positively correlated with absolute monocyte count (\u3c1 = 0.53, p < 0.05), while LTE4 showed a positive correlation with relative eosinophil levels (\u3c1 = 0.46, p < 0.05) and a negative correlation with the relative neutrophil levels (\u3c1 = 120.56, p < 0.01). These results highlight the validated method as a valuable tool for investigating distinct inflammatory pathways in epidemiological settings and clinical research
Sterile, religiously neutral, and colourblind: on religious symbols in healthcare
No full textAbstract: This article explores the right of caregivers to wear religious dress in Europe, focusing on four countries: France, Belgium, the UK, and the Netherlands. It highlights the varying approaches to secularism, with stricter scrutiny on prohibitions in the UK and the Netherlands, while France and Belgium lean towards a form of outward neutrality that prohibits religious symbols, particularly in public services. While prohibitions on religious dress for caregivers might aim to protect the rights to equal treatment of patients, it raises concerns about its compatibility with equality law. Despite a shared European human rights framework, these policies result in inconsistent legal outcomes across countries, challenging the principles of non-discrimination and religious freedom. The article also questions the justification of blanket bans under health and safety standards, emphasizing the need for reasonable accommodation. Furthermore, it stresses that any restrictions on religious dress that are in place to protect the rights and freedoms of others should be based on objective, evidence-based reasoning. In this sense, patients\u2019 perceptions of religious symbols should not be generalized, especially considering the rights of minoritized or religious patients
Numerical investigations into boiling surface design
No full textAbstract: The design of immersion cooling systems is becoming of increasing importance as higher heat transfer rates are sought for the cooling of microelectronics. The influence of boiling surface design is still not fully understood but may play a key role in achieving the desired heat transfer enhancement. Previous research has demonstrated that artificial cavities can enhance nucleate boiling heat transfer, with cavity radius and wall inclination playing a significant role in bubble dynamics and rewetting heat transfer. The aim of this study is to investigate the influence of fluid properties, contact angle and cavity radius on bubble departure diameter and develop a simple design methodology for cavity arrays. Bubbles under equilibrium conditions were simulated using well-known numerical models. For a given set of fluid properties, the maximum bubble volume for each combination of contact angle and cavity radius was taken to be the bubble volume at departure. It was found that bubble departure behavior is dependent on contact angle for cavities smaller than a critical cavity radius. For larger cavities, the behavior is instead dependent on the cavity radius The proposed model allows for bubble departure diameters to be predicted for a wide range of fluids, cavity radii and contact angles, aiding the design process of cavity arrays
The Alzheimer\u2019s therapeutic Lecanemab attenuates A\u3b2 pathology by inducing an amyloid-clearing program in microglia
No full textAbstract: Controversies over anti-amyloid immunotherapies underscore the need to elucidate their mechanisms of action. Here we demonstrate that Lecanemab, a leading anti-\u3b2-amyloid (A\u3b2) antibody, mediates amyloid clearance by activating microglial effector functions. Using a human microglia xenograft mouse model, we show that Lecanemab significantly reduces A\u3b2 pathology and associated neuritic damage, while neither fragment crystallizable (Fc)-silenced Lecanemab nor microglia deficiency elicits this effect despite intact plaque binding. Single-cell RNA sequencing and spatial transcriptomic analyses reveal that Lecanemab induces a focused transcriptional program that enhances phagocytosis, lysosomal degradation, metabolic reprogramming, interferon \u3b3 genes and antigen presentation. Finally, we identify SPP1/osteopontin as a major factor induced by Lecanemab treatment and demonstrate its role in promoting A\u3b2 clearance. These findings highlight that effective amyloid removal depends on the engagement of microglia through the Fc fragment, providing critical insights for optimizing anti-amyloid therapies in Alzheimer\u2019s disease
Discrepancies between ESTRO/ESGO/SIOPE and NCCN guidelines in the management of vaginal cancer : a call for harmonization
No full textAbstract: Current vaginal cancer guidelines need refining. First of all: Cancer can only be called vaginal if there is no cervical or vulval involvement or in case of a prior anogenital cancer were the HPV type(s) between the cancers are different. Secondly: Surgery, accompanied by SLN mapping, should be the first-line treatment for early-stage vaginal cancer. Thirdly: HPV testing and typing should be part of both pretreatment evaluation and follow-up