Students Teaching Students: Student-Led Ultrasound Curriculum in Medical School Education

Introduction

With the expanding use of point-of-care ultrasound throughout medical specialties for the rapid bedside assessment integral to patient care, medical schools have sought to incorporate ultrasound education into their curriculum. Second-year medical students (MS2s) at our institution met this demand by forming the Ultrasound Student Instructor Cadre (USSIC), a longitudinal ultrasound curriculum where MS2s teach first-year medical students (MS1s). The objectives of this study were to assess the ultrasound knowledge of medical students and their perceptions of ultrasound incorporation into their medical education.

Methods

Our flipped classroom curriculum consisted of four lessons (cardiopulmonary, gastrointestinal, genitourinary, and musculoskeletal) composed of videos, didactic lessons, and hands-on probe-time, with 15-minute pre- and post-assessments. Paired Wilcoxon signed-rank tests were performed to evaluate the differences in the pre- and post-assessment scores for each teaching session. Additionally, an end-of-the-year survey assessed the perceived preparedness and overall satisfaction of the MS1s with the course.

Results

The differences between the pre- and post-assessments for each teaching session were statistically significant: cardiopulmonary (45.6 ± 16.9% vs. 82.9 ± 9.4%, p < 0.0001, n = 55), gastrointestinal (53.9 ± 18.0% vs. 84.1 ± 13.5%, p < 0.0001, n = 54), genitourinary (68.9 ± 19.1% vs. 91.4 ± 14.4%, p < 0.0001, n = 64), and musculoskeletal (33.6 ± 14.7% vs. 78.2 ± 18.2%, p < 0.0001, n = 55).

Conclusion

Our study suggests that MS1s met the learning objective for each teaching session. Furthermore, MS1s who became USSIC instructors as MS2s felt more prepared and were more satisfied with the course. This study demonstrates the efficacy of student-led instruction in ultrasound, and we offer our model for adoption into other medical schools.

Nuclear receptor Ftz-f1 promotes follicle maturation and ovulation partly via bHLH/PAS transcription factor Sim

The NR5A-family nuclear receptors are highly conserved and function within the somatic follicle cells of the ovary to regulate folliculogenesis and ovulation in mammals; however, their roles in Drosophila ovaries are largely unknown. Here, we discover that Ftz-f1, one of the NR5A nuclear receptors in Drosophila, is transiently induced in follicle cells in late stages of oogenesis via ecdysteroid signaling. Genetic disruption of Ftz-f1 expression prevents follicle cell differentiation into the final maturation stage, which leads to anovulation. In addition, we demonstrate that the bHLH/PAS transcription factor Single-minded (Sim) acts as a direct target of Ftz-f1 to promote follicle cell differentiation/maturation and that Ftz-f1’s role in regulating Sim expression and follicle cell differentiation can be replaced by its mouse homolog steroidogenic factor 1 (mSF-1). Our work provides new insight into the regulation of follicle maturation in Drosophila and the conserved role of NR5A nuclear receptors in regulating folliculogenesis and ovulation.

When animals reproduce, females release eggs from their ovaries which then get fertilized by sperm from males. Each egg needs to properly mature within a collection of cells known as follicle cells before it can be let go. As the egg matures, so do the follicle cells surrounding it, until both are primed and ready to discharge the egg from the ovary. Mammals rely on a protein called SF-1 to mature their follicle cells, but it is unclear how this process works.

Most animals – from humans to fruit flies – release their eggs in a very similar way, using many of the same proteins and genes. For example, the gene for SF-1 in mammals is similar to a gene in fruit flies which codes for another protein called Ftz-f1. Since it is more straightforward to study ovaries in fruit flies than in humans and other mammals, investigating this protein could shed light on how follicle cells mature. However, it remained unclear whether Ftz-f1 plays a similar role to its mammalian counterpart.

Here, Knapp et al. show that Ftz-f1 is present in the follicle cells of fruit flies and is required for them to properly mature. Ftz-f1 controlled this process by regulating the activity of another protein called Sim. Further experiments found that the gene that codes for the SF-1 protein in mice was able to compensate for the loss of Ftz-f1 and drive follicle cells to mature.

Studying how ovaries release eggs is an essential part of understanding female fertility. This work highlights the similarities between these processes in mammals and fruit flies and may help us understand how ovaries work in humans and other mammals. In the future, the findings of Knapp et al. may lead to new therapies for infertility in females and other disorders that affect ovaries.

SUMO conjugation regulates immune signalling

Post-translational modifications (PTMs) are critical drivers and attenuators for proteins that regulate immune signalling cascades in host defence. In this review, we explore functional roles for one such PTM, the small ubiquitin-like modifier (SUMO). Very few of the SUMO conjugation targets identified by proteomic studies have been validated in terms of their roles in host defence. Here, we compare and contrast potential SUMO substrate proteins in immune signalling for flies and mammals, with an emphasis on NFκB pathways. We discuss, using the few mechanistic studies that exist for validated targets, the effect of SUMO conjugation on signalling and also explore current molecular models that explain regulation by SUMO. We also discuss in detail roles of evolutionary conservation of mechanisms, SUMO interaction motifs, crosstalk of SUMO with other PTMs, emerging concepts such as group SUMOylation and finally, the potentially transforming roles for genome-editing technologies in studying the effect of PTMs.

Can You Teach Yourself Point-of-care Ultrasound to a Level of Clinical Competency? Evaluation of a Self-directed Simulation-based Training Program

Introduction

Self-directed learning in medical professions is established as an effective method of training in certain modalities. Furthermore, simulation technology is becoming widely used and accepted as a valid method of training for various medical skills, with ultrasound being one of the best studied. The use of point-of-care ultrasound (PoCUS) in the practice of emergency medicine is well established, and PoCUS is a core competency of the Royal College of Physicians and Surgeons of Canada emergency medicine standards. The primary goal of our study was to assess the effectiveness of a self-directed simulation-based training program for medical students, in terms of achieving competency in basic PoCUS scans.

Methods

Fourteen second-year medical students with no prior ultrasound experience were provided access to online study modules created by SonoSim ultrasound training solutions (SonoSim, Santa Monica, CA, US), covering ultrasound theory and methodology, and attended a two-hour introductory session where they were introduced to the study protocol, simulation equipment, and software. Participants then undertook self-directed ultrasound simulation training throughout the year, using the CAE Vimedix PoCUS simulator (CAE Healthcare, Sarasota, FL, US) and the SonoSim ultrasound training solution system. Upon reaching 10 (and 25) scans in each of the four categories (cardiac, abdomen, aorta, and pelvic), a triggered assessment was arranged in which participants scanned a live volunteer under the direct supervision of PoCUS-certified physicians. The physicians scored the participant attempts in terms of image acquisition, interpretation, and clinical understanding. No feedback was provided to the participants. Following the study, participants submitted feedback regarding the design of the study and were asked to rank their preferred training program protocols out of a provided list of five different options.

Results

At the first triggered assessment (after completing only 10 scans in each category), four out of 14 participants were scored as competent in the aorta scan, two out of 14 participants were competent in the pelvic scan, and none of the participants were competent in both the cardiac and abdominal scans. Only nine out of 14 participants completed the second triggered assessment (after completing 25 scans in each category). At the second assessment, only three participants were scored as competent in the aorta scan, two participants were competent in the cardiac scan, and one participant was competent in the pelvic scan. None of the 14 learners completed the final phase of the training and assessment protocol. Feedback following the termination of the study showed that none of the participants supported continuing the study protocol as designed originally, and the preferred study design consisted of a full-day introductory course with live models and simulation, followed by self-directed learning with simulation and live models until 50 scans in each category were achieved.

Conclusion

We were unable to demonstrate the achievement of competence in PoCUS in medical learners engaged in our combined self-directed simulation-based training program. This is in contrast to the considerable literature supporting self-directed learning and simulation-based learning for other skills. Feedback from faculty, curriculum integration, and alignment with clinical experience may be beneficial.

Development of neuroendocrine lineages requires the bHLH-PAS transcription factor SIM1

The bHLH-PAS transcription factor SIM1 is expressed during the development of the hypothalamic-pituitary axis in three hypothalamic nuclei: the paraventricular nucleus (PVN), the anterior periventricular nucleus (aPV), and the supraoptic nucleus (SON). To investigate Sim1 function in the hypothalamus, we produced mice carrying a null allele of Sim1 by gene targeting. Homozygous mutant mice die shortly after birth. Histological analysis shows that the PVN and the SON of these mice are hypocellular. At least five distinct types of secretory neurons, identified by the expression of oxytocin, vasopressin, thyrotropin-releasing hormone, corticotropin-releasing hormone, and somatostatin, are absent in the mutant PVN, aPV, and SON. Moreover, we show that SIM1 controls the development of these secretory neurons at the final stages of their differentiation. A subset of these neuronal lineages in the PVN/SON are also missing in mice bearing a mutation in the POU transcription factor BRN2. We provide evidence that, during development of the Sim1 mutant hypothalamus, the prospective PVN/SON region fails to express Brn2. Our results strongly indicate that SIM1 functions upstream to maintain Brn2 expression, which in turn directs the terminal differentiation of specific neuroendocrine lineages within the PVN/SON.