Voluntary peer-led exam preparation course for international first year students: Tutees’ perceptions

Background: While the number of international students has increased over the last decade, such students face diverse challenges due to language and cultural barriers. International medical students suffer from personal distress and a lack of support. Their performance is significantly lower than non-international peers in clinical examinations. We investigated whether international students benefit from a peer-led exam preparation course. Methods: An exam preparation course was designed, and relevant learning objectives were defined. Two evaluations were undertaken: Using a qualitative approach, tutees (N = 10) were asked for their thoughts and comments in a semi-structured interview at the end of the semester. From a quantitative perspective, all participants (N = 22) were asked to complete questionnaires at the end of each course session. Results: International students reported a range of significant benefits from the course as they prepared for upcoming exams. They benefited from technical and didactic, as well as social learning experiences. They also considered aspects of the tutorial’s framework helpful. Conclusion: Social and cognitive congruence seem to be the key factors to success within international medical students’ education. If tutors have a migration background, they can operate as authentic role models. Furthermore, because they are still students themselves, they can offer support using relevant and understandable language

An AI-based segmentation and analysis pipeline for high-field MR monitoring of cerebral organoids

Abstract Cerebral organoids recapitulate the structure and function of the developing human brain in vitro, offering a large potential for personalized therapeutic strategies. The enormous growth of this research area over the past decade with its capability for clinical translation makes a non-invasive, automated analysis pipeline of organoids highly desirable. This work presents a novel non-invasive approach to monitor and analyze cerebral organoids over time using high-field magnetic resonance imaging and state-of-the-art tools for automated image analysis. Three specific objectives are addressed, (I) organoid segmentation to investigate organoid development over time, (II) global cysticity classification and (III) local cyst segmentation for organoid quality assessment. We show that organoid growth can be monitored reliably over time and cystic and non-cystic organoids can be separated with high accuracy, with on par or better performance compared to state-of-the-art tools applied to brightfield imaging. Local cyst segmentation is feasible but could be further improved in the future. Overall, these results highlight the potential of the pipeline for clinical application to larger-scale comparative organoid analysis

Individual glioblastoma cells harbor both proliferative and invasive capabilities during tumor progression

Ratliff M, Karimian-Jazi K, Hoffmann DC, et al. Individual glioblastoma cells harbor both proliferative and invasive capabilities during tumor progression. Neuro-Oncology . 2023.Background Glioblastomas are characterized by aggressive and infiltrative growth, and by striking heterogeneity. The aim of this study was to investigate whether tumor cell proliferation and invasion are interrelated, or rather distinct features of different cell populations. Methods Tumor cell invasion and proliferation were longitudinally determined in real-time using 3D in vivo 2-photon laser scanning microscopy over weeks. Glioblastoma cells expressed fluorescent markers that permitted the identification of their mitotic history or their cycling versus non-cycling cell state. Results Live reporter systems were established that allowed us to dynamically determine the invasive behavior, and previous or actual proliferation of distinct glioblastoma cells, in different tumor regions and disease stages over time. Particularly invasive tumor cells that migrated far away from the main tumor mass, when followed over weeks, had a history of marked proliferation and maintained their proliferative capacity during brain colonization. Infiltrating cells showed fewer connections to the multicellular tumor cell network, a typical feature of gliomas. Once tumor cells colonized a new brain region, their phenotype progressively transitioned into tumor microtube-rich, interconnected, slower-cycling glioblastoma cells. Analysis of resected human glioblastomas confirmed a higher proliferative potential of tumor cells from the invasion zone. Conclusions The detection of glioblastoma cells that harbor both particularly high proliferative and invasive capabilities during brain tumor progression provides valuable insights into the interrelatedness of proliferation and migration-2 central traits of malignancy in glioma. This contributes to our understanding of how the brain is efficiently colonized in this disease