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Purpose Uveal melanoma with a bad prognosis contain high numbers of infiltrating macrophages, especially of the M2 phenotype, and different subsets of lymphocytes. The aim of this study is to determine the presence of inflammatory cells in uveal melanoma‐containing eyes enucleated after different types of irradiation, i.e. ruthenium‐106 brachytherapy, sandwich therapy, or proton beam irradiation. Methods We analyzed 46 eyes enucleated due to tumor recurrence, non‐responsiveness, or complications after irradiation. Immunofluorescence staining was performed to determine the presence of CD68+ and CD68+CD163+macrophages, CD3+, CD8+ and Foxp3+ regulatory T lymphocytes. Outcomes were compared with known clinical and histological prognostic parameters. Results Numbers of CD68+ and CD68+CD163+ macrophages in secondarily‐enucleated eyes varied widely, but was not related to the reason for enucleation. The median of CD3, CD8, FoxP3+ lymphocyte counts was 55, 99 and 9 cells/mm2, respectively. When compared to primarily‐enucleated eyes, the lymphocytic infiltration was significantly (p<.02) higher in irradiated eyes. Conclusion Numbers of T‐lymphocytes and macrophages varied widely. Irradiation has no clear effect on the number and type of macrophages in uveal melanoma. However, there were higher numbers of lymphocytes in previously irradiated uveal melanoma. [ABSTRACT FROM AUTHOR]

Understanding the ultrasound pressure-driven dynamics of microbubbles confined in viscoelastic materials is relevant for multiple biomedical applications, ranging from contrast-enhanced ultrasound imaging to ultrasound-assisted drug delivery. The volumetric oscillations of spherical bubbles are analyzed using the Rayleigh-Plesset equation, which describes the conservation of mass and momentum in the surrounding medium. Several studies have considered an extension of the Rayleigh-Plesset equation for bubbles embedded into viscoelastic media, but these are restricted to a particular choice of constitutive model and/or to small deformations. Here, we derive a unifying equation applicable to bubbles in viscoelastic media with arbitrary complex moduli and that can account for large bubble deformations. To derive this equation, we borrow concepts from finite-strain theory. We validate our approach by comparing the result of our model to previously published results and extend it to show how microbubbles behave in arbitrary viscoelastic materials. In particular, we use our viscoelastic Rayleigh-Plesset model to compute the bubble dynamics in benchmarked viscoelastic liquids and solids., (© 2024 Acoustical Society of America.)

Background: Ethiopia has scaled up medical education to improve access to healthcare which presented challenges to maintaining training quality. We conducted a study to assess the clinical competence of graduating medical students and the associated factors., Methods and Materials: A pretest assessment of a quasi-experimental study was conducted in 10 medical schools with a sample size of 240 students. We randomly selected 24 students per school. Clinical competence was assessed in a 12-station objective structured clinical examination. The clinical learning environment (CLE), simulation training, and practice exposure were self-rated. Mean scores for clinical competence, and satisfaction in the CLE and simulation training were calculated. Proportions of students with practice exposure, and who agreed on CLE and simulation items were done. Independent t-tests were used to look at competence differences among subgroups. Bivariate and multiple linear regression models were fitted for the outcome variable: competence score. A 95% statistical confidence interval and p-value < 0.05 were used for making statistical decisions. A 75% cut-off score was used to compare competence scores., Results: Graduating medical students had a mean competence score of 72%. Low scores were reported in performing manual vacuum aspiration (62%), lumbar puncture (64%), and managing childbirth (66%). Female students (73%) had a significantly higher competence score than males (70%). Higher cumulative grade point average (CGPA), positive appraisal of the CLE, and conducting more clinical procedures were associated with greater competence scores. Nearly half of the students were not satisfied with the clinical practice particularly due to the large student number and issues affecting the performance assessment. About two-thirds of the students were not satisfied with the sufficiency of models and equipment, and the quality of feedback during simulation training. Nearly one-third of the students never performed lumbar puncture, manual vacuum aspiration, and venipuncture., Conclusions: Medical students had suboptimal clinical competence. A better clinical learning environment, higher cumulative GPA, and more practice exposure are associated with higher scores. There is a need to improve student clinical practice and simulation training. Strengthening school accreditation and graduates' licensing examinations is also a way forward., (© 2023. The Author(s).)

Background: In The Netherlands, physicians specialized in global health and tropical medicine (Ps-GHTM) are trained to work in low-resource settings (LRS) after their training program of 27 months. After working for a period of time in LRS, many Ps-GHTM continue their careers in the Dutch healthcare system. While there is limited evidence regarding the value of international health experience for medical students and residents, it is unknown to what extent this applies to Ps-GHTM and to their clinical practice in the Netherlands., Methods: In this qualitative study we conducted semi-structured interviews and focus group discussions (FGDs) with Ps-GHTM to explore the perceived applicability of their experience abroad for their subsequent return to the Netherlands. Topic guides were developed using literature about the applicability of working abroad. Findings from the interviews served as a starting point for FGDs. The interviews and FGDs were analysed using directed content analysis., Results: 15 themes are described relating experience abroad to healthcare delivery in The Netherlands: broad medical perspective, holistic perspective, adaptive communication skills, creativity, flexibility, cultural awareness, self-reliance, clinical competence, cost awareness, public health, leadership, open-mindedness, organization of care, self-development, and teamwork. Highlighting the variety in competencies and the complexity of the topic, not all themes were recognized by all respondents in the FGDs nor deemed equally relevant. Flexibility, cultural awareness and holistic perspective are examples of important benefits to work experience in LRS., Conclusion: Ps-GHTM bring their competencies to LRS and return to the Netherlands with additionally developed skills and knowledge. These may contribute to healthcare delivery in the Netherlands. This reciprocal value is an important factor for the sustainable development of global health. Identifying the competencies derived from work experience in LRS could give stakeholders insight into the added value of Ps-GHTM and partly help in refining the specialization program., (© 2023. The Author(s).)

Objectives: Understanding the competency of educators is key to informing faculty development, recruitment and performance monitoring. This study aimed to assess the core teaching competency of nursing, midwifery and biomedical educators, and associated factors in Ethiopia., Design: An institution-based cross-sectional study was conducted in January 2020 using structured tools adapted from the WHO's nurse and midwifery educator competency frameworks., Setting: Two health science colleges and nine student practice sites in Ethiopia., Participants: All classroom instructors and clinical preceptors of nursing, midwifery and biomedical technician training programmes, and all the graduating class students., Measures: Overall teaching competency scores, teaching domain competency scores, competency gaps and performance gaps of educators were outcome measures. Past training on teaching skills courses, teaching experiences and sociodemographic characteristics of educators are associated factors., Results: Most educators were not trained in teaching methods (82%). The teaching competency scores of classroom instructors and clinical preceptors were 61.1% and 52.5%, respectively. Competency gaps were found in using active learning methods, performance assessment, feedback and digital learning. Professional background of classroom instructors had a significant and strong association with their competency score (p=0.004; V = 0.507). Age and teaching experience of clinical preceptors had significant associations with their competency score (p=0.023 and p=0.007, respectively) and had strong associations (V=0.280 and 0.323, respectively). Sex of students and their perceptions of how well the educators give education resources had a significant and strong association (p<0.001; V = 0.429)., Conclusions: Nursing, midwifery and biomedical educators lacked the competency to undertake important teaching roles, which could contribute to the low quality of education. More attention should be given to strengthening faculty development., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Recently, super-resolution ultrasound imaging with ultrasound localization microscopy (ULM) has received much attention. However, ULM relies on low concentrations of microbubbles in the blood vessels, ultimately resulting in long acquisition times. Here, we present an alternative super-resolution approach, based on direct deconvolution of single-channel ultrasound radio-frequency (RF) signals with a one-dimensional dilated convolutional neural network (CNN). This work focuses on low-frequency ultrasound (1.7 MHz) for deep imaging (10 cm) of a dense cloud of monodisperse microbubbles (up to 1000 microbubbles in the measurement volume, corresponding to an average echo overlap of 94%). Data are generated with a simulator that uses a large range of acoustic pressures (5-250 kPa) and captures the full, nonlinear response of resonant, lipid-coated microbubbles. The network is trained with a novel dual-loss function, which features elements of both a classification loss and a regression loss and improves the detection-localization characteristics of the output. Whereas imposing a localization tolerance of 0 yields poor detection metrics, imposing a localization tolerance corresponding to 4% of the wavelength yields a precision and recall of both 0.90. Furthermore, the detection improves with increasing acoustic pressure and deteriorates with increasing microbubble density. The potential of the presented approach to super-resolution ultrasound imaging is demonstrated with a delay-and-sum reconstruction with deconvolved element data. The resulting image shows an order-of-magnitude gain in axial resolution compared to a delay-and-sum reconstruction with unprocessed element data.

Background: High-risk human papillomavirus (hrHPV) testing has been recommended by the World Health Organization as the primary screening test in cervical screening programs. The option of self-sampling for this screening method can potentially increase women's participation. Designing screening programs to implement this method among underscreened populations will require contextualized evidence., Methods: PREvention and SCReening Innovation Project Toward Elimination of Cervical Cancer (PRESCRIP-TEC) will use a multi-method approach to investigate the feasibility of implementing a cervical cancer screening strategy with hrHPV self-testing as the primary screening test in Bangladesh, India, Slovak Republic and Uganda. The primary outcomes of study include uptake and coverage of the screening program and adherence to follow-up. These outcomes will be evaluated through a pre-post quasi-experimental study design. Secondary objectives of the study include the analysis of client-related factors and health system factors related to cervical cancer screening, a validation study of an artificial intelligence decision support system and an economic evaluation of the screening strategy., Discussion: PRESCRIP-TEC aims to provide evidence regarding hrHPV self-testing and the World Health Organization's recommendations for cervical cancer screening in a variety of settings, targeting vulnerable groups. The main quantitative findings of the project related to the impact on uptake and coverage of screening will be complemented by qualitative analyses of various determinants of successful implementation of screening. The study will also provide decision-makers with insights into economic aspects of implementing hrHPV self-testing, as well as evaluate the feasibility of using artificial intelligence for task-shifting in visual inspection with acetic acid., Trial Registration: ClinicalTrials.gov, NCT05234112 . Registered 10 February 2022., (© 2022. The Author(s).)

Background: Local blood flow affects vascular disease and outcomes of endovascular treatment, but quantifying it is challenging, especially inside stents. We assessed the feasibility of blood flow quantification in native and stented femoral arteries, using high-frame-rate (HFR) contrast-enhanced ultrasound (CEUS) particle image velocimetry (PIV), also known as echoPIV., Methods: Twenty-one patients with peripheral arterial disease, recently treated with a stent in the femoral artery, were included. HFR CEUS measurements were performed in the native femoral artery and at the inflow and outflow of the stent. Two-dimensional blood flow was quantified through PIV analysis. EchoPIV recordings were visually assessed by five observers and categorised as optimal, partial, or unfeasible. To evaluate image quality and tracking performance, contrast-to-tissue ratio (CTR) and vector correlation were calculated, respectively., Results: Fifty-eight locations were measured and blood flow quantification was established in 49 of them (84%). Results were optimal for 17/58 recordings (29%) and partial for 32 recordings (55%) due to loss of correlation (5/32; 16%), short vessel segment (8/32; 25%), loss of contrast (14/32; 44%), and/or shadows (18/32; 56%). In the remaining 9/58 measurements (16%) no meaningful flow information was visualised. Overall, CTR and vector correlation were lower during diastole. CTR and vector correlation were not different between stented and native vessel segments, except for a higher native CTR at the inflow during systole (p = 0.037)., Conclusions: Blood flow quantification is feasible in untreated and stented femoral arteries using echoPIV. Limitations remain, however, none of them related to the presence of the stent., Trial Registration: ClinicalTrials.gov, NCT04934501 (retrospectively registered)., (© 2022. The Author(s) under exclusive licence to European Society of Radiology.)