"Meet the patient" session: a strategy to teach medical students about autonomic dysfunction after spinal cord injury.

Dysregulation of the autonomic nervous system is an important long-term consequence of spinal cord injury (SCI). Yet, there is a scarcity of teaching resources about this topic for preclinical medical students. Given the association of SCI sequelae with emergency complications and mortality, it is imperative to equip medical students with the ability to recognize them. We designed a "Meet the Patient" (MTP) session with the primary goal to enhance student learning about SCI sequelae by interacting with patients and listening to real-life stories. The session primarily focused on recognizing triggers and symptoms of autonomic dysreflexia (AD) and discussing the loss of bowel and bladder control, while providing opportunities to learn more about living with SCI from patients' real-life experiences. During the MTP session, patients living with SCI discussed their experience with AD, neurogenic bowel and bladder, and spasticity, among other SCI sequelae. We evaluated the outcomes of the MTP session by assessing numerical performance in questions related to the session (post-session quiz and final exam) and students' satisfaction (post-session survey) in two subsequent academic years. The numerical performance in SCI-questions was high for both academic years (and higher than national average for the final exam question), indicating adequate acquisition of knowledge. Satisfaction with the session was high, with most students indicating that the session helped them consolidate their knowledge about the topic.

Combatting Neurophobia: A Proposed Preliminary Educational Model to Promote Neurophilia.

When we reflect on medical education as a whole, novelty in structure and content promotes growth and enhances student outcomes. The teaching of neurology is no different and presents a more unique hurdle in its instruction considering the well-described phenomenon of neurophobia. With the burden of neurological diseases on the rise, there is a heightened demand for medical educators to understand the possible causes of this educational misalignment and implement solutions necessary to ensure adequate education of students. In this study, we describe a novel approach to neurology education for second-year medical students to stimulate neurophilia, incorporating evidence-based approaches within the identified areas-Active Learning Pedagogies, Diagnostic and Clinical Reasoning, Use of Technology, Field Exposure and Mentorship, and Innovation. Students demonstrated superior academic performance on the National Board of Medical Examiners (NBME) neurology assessments and generally positive feedback on the use of innovative approaches to teaching and learning. Overall, we propose this method of teaching neurology as a model educational platform that aims to reduce neurophobia and promote neurophilia.

Remote Learning and Its Impact on Newly Matriculated Medical Students.

Objective The coronavirus disease 2019 (COVID-19) pandemic has led to massive disruptions in medical education. In the fall of 2020, newly matriculated medical students around the country started medical school in a remote learning setting. The purpose of this study is to assess the impact of remote learning during the COVID-19 pandemic on academic performance and student satisfaction among first-year medical students. Methods The newest cohort of first-year medical students (class of 2024; n = 128) who completed their first basic science course, "Genes, Molecules & Cells (GMC)," using an adapted remote format was compared to the prior year's cohort (class of 2023; n = 122) of first-year medical students who were taught using traditional approaches. The items that were compared were numerical performance on exams and quizzes, study strategies, and course evaluation in GMC. Data were analyzed with a two-sided t-test and Pearson correlation coefficient. Students' perception of remote learning was also reported and results were obtained using a five-point Likert scale through anonymous surveys via E-value. Results No statistical difference was observed in students' performance on the midterm and final examinations between the two cohorts in both multiple-choice and written examinations. Mean multiple-choice question (MCQ) midterm students' performance in remote learning compared to traditional learning cohort was 75.9%, standard deviation (SD) 6.1 to 75.89%, SD 6.49, respectively. Mean MCQ final students' performance was 84%, SD 6.37 (class of 2024) to 85%, SD 8.78 (class of 2023). Students' satisfaction with their learning experience was similar among the two groups (class of 2024: mean = 4.61, SD 0.66; class of 2023: mean = 4.57, SD 0.68). Most students (70%) in the remote learning cohort had a positive opinion of remote learning. Of the students, 17% reported feeling disconnected, isolated, or not actively involved. Conclusions The results of this study demonstrate that not only is remote learning effective but that the students were also resilient in their adaptation to a new learning format. Our experience highlights the importance of including wellness solutions to mitigate the feeling of isolation and disconnection during remote learning.

Emerging role for autophagy in the removal of aggresomes in Schwann cells.

The presence of protein aggregates in the nervous system is associated with various pathological conditions, yet their contribution to disease mechanisms is poorly understood. One type of aggregate, the aggresome, accumulates misfolded proteins destined for degradation by the ubiquitin-proteasome pathway. Peripheral myelin protein 22 (PMP22) is a short-lived Schwann cell (SC) protein that forms aggresomes when the proteasome is inhibited or the protein is overexpressed. Duplication, deletion, or point mutations in PMP22 are associated with a host of demyelinating peripheral neuropathies, suggesting that, for normal SC cell function, the levels of PMP22 must be tightly regulated. Therefore, we speculate that mutant, misfolded PMP22 might overload the proteasome and promote aggresome formation. To test this, sciatic nerves of Trembler J (TrJ) neuropathy mice carrying a leucine-to-proline mutation in PMP22 were studied. In TrJ neuropathy nerves, PMP22 has an extended half-life and forms aggresome-like structures that are surrounded by molecular chaperones and lysosomes. On the basis of these characteristics, we hypothesized that PMP22 aggresomes are transitory, linking the proteasomal and lysosomal protein degradation pathways. Here we show that Schwann cells have the ability to eliminate aggresomes by a mechanism that is enhanced when autophagy is activated and is primarily prevented when autophagy is inhibited. This mechanism of aggresome clearance is not unique to peripheral glia, because L fibroblasts were also capable of removing aggresomes. Our results provide evidence for the involvement of the proteasome pathway in TrJ neuropathy and for the role of autophagy in the clearance of aggresomes.

Muscle injection of AAV-NT3 promotes anatomical reorganization of CST axons and improves behavioral outcome following SCI.

Here we propose the use of adeno-associated virus (AAV) vectors as a non-invasive vehicle for the nervous system to deliver genes to spinal motoneurons, based on their retrograde transport from muscle. Long-term protein expression in lower cervical motoneurons was achieved after injections of AAV into the triceps, independently of serotypes 1, 2, or 5. Muscle injections of AAV5-neurotrophin 3 (NT3) resulted in a significant increase in the levels of NT3 in the cervical enlargement, compared to those obtained after injections of AAV5-GFP. Following a dorsal lesion at C4/C5, animals injected with AAV5-NT3 made fewer errors (footslips) in the horizontal ladder test compared to those injected with AAV5-GFP. In parallel, the number and length of corticospinal tract (CST) fibers circumventing the injury site were significantly increased in rats injected with AAV5-NT3. Compared to controls, we observed less astrogliosis and less CST axonal retraction and/or enhanced sprouting in animals injected with AAV5-NT3. In sum, we demonstrate here that the delivery of nt3 via retrograde transport of AAV from triceps to cervical motoneurons leads to reduced functional loss and anatomical reorganization of the CST following injury, without introducing additional injury to the spinal cord.

The formation of peripheral myelin protein 22 aggregates is hindered by the enhancement of autophagy and expression of cytoplasmic chaperones.

The accumulation of misfolded proteins is associated with various neurodegenerative conditions. Peripheral myelin protein 22 (PMP22) is a hereditary neuropathy-linked, short-lived molecule that forms aggresomes when the proteasome is inhibited or the protein is mutated. We previously showed that the removal of pre-existing PMP22 aggregates is assisted by autophagy. Here we examined whether the accumulation of such aggregates could be suppressed by experimental induction of autophagy and/or chaperones. Enhancement of autophagy during proteasome inhibition hinders protein aggregate formation and correlates with a reduction in accumulated proteasome substrates. Conversely, simultaneous inhibition of autophagy and the proteasome augments the formation of aggregates. An increase of heat shock protein levels by geldanamycin treatment or heat shock preconditioning similarly hampers aggresome formation. The beneficial effects of autophagy and chaperones in preventing the accumulation of misfolded PMP22 are additive and provide a potential avenue for therapeutic approaches in hereditary neuropathies linked to PMP22 mutations.

Alterations in degradative pathways and protein aggregation in a neuropathy model based on PMP22 overexpression.

Charcot-Marie-Tooth disease type 1A (CMT1A) is commonly associated with duplication of the peripheral myelin protein 22 (PMP22) gene. Mice expressing seven copies of the human PMP22, termed C22, suffer from a demyelinating neuropathy and display phenotypic traits of CMT1A. In this article, we investigate whether protein aggregates play a role in the CMT1A-like pathology of C22 mice. Utilizing biochemical and immunochemical tools, we found slowed turnover rate of the newly-synthesized PMP22 and the presence of cytoplasmic protein aggregates in affected nerves. The formation of these aggregates correlates with reduced proteasome activity and the accumulation of detergent-insoluble ubiquitinated substrates. A fraction of the aggregates associates with autophagosomes and lysosomes. Together, these data indicate that as a result of missorting and inefficient proteasomal degradation, the aggregation of PMP22 and recruitment of autophagosomes and lysosomes are key factors in the subcellular pathogenesis of CMT1A neuropathies.

Impaired proteasome activity and accumulation of ubiquitinated substrates in a hereditary neuropathy model.

Accumulation of misfolded proteins and alterations in the ubiquitin-proteasome pathway are associated with various neurodegenerative conditions of the CNS and PNS. Aggregates containing ubiquitin and peripheral myelin protein 22 (PMP22) have been observed in the Trembler J mouse model of Charcot-Marie-Tooth disease type 1A demyelinating neuropathy. In these nerves, the turnover rate of the newly synthesized PMP22 is reduced, suggesting proteasome impairment. Here we show evidence of proteasome impairment in Trembler J neuropathy samples compared with wild-type, as measured by reduced degradation of substrate reporters. Proteasome impairment correlates with increased levels of polyubiquitinated proteins, including PMP22, and the recruitment of E1, 20S and 11S to aggresomes formed either spontaneously due to the Trembler J mutation or upon proteasome inhibition. Furthermore, myelin basic protein, an endogenous Schwann cell proteasome substrate, associates with PMP22 aggregates in affected nerves. Together, our data show that in neuropathy nerves, reduced proteasome activity is coupled with the accumulation of ubiquitinated substrates, and the recruitment of proteasomal pathway constituents to aggregates. These results provide novel insights into the mechanism by which altered degradation of Schwann cell proteins may contribute to the pathogenesis of certain PMP22 neuropathies.

The WD-repeat protein GRWD1: potential roles in myeloid differentiation and ribosome biogenesis.

A cDNA fragment originally identified in U-937 cells as a vitamin D(3)-regulated gene is here designated the glutamate-rich WD-repeat (GRWD1) gene. WD-repeat proteins are a class of functionally divergent molecules that cooperate with other proteins to regulate cellular processes. GRWD1 encodes a 446-amino-acid protein containing a glutamate-rich region followed by four WD repeats. The yeast homologue of GRWD1, Rrb1, has been shown to be an essential protein involved in ribosome biogenesis. Northern analysis of GRWD1 message levels in the myeloid cell line HL-60 undergoing differentiation induced by vitamin D(3) or retinoic acid demonstrate downregulation coincident with slowing of cellular proliferation. A siRNA designed to downregulate GRWD1 similarly results in a decrease in cellular proliferation within 293 cells. Metabolic labeling of cells expressing the siRNA to GRWD1 shows a decrease in global protein synthesis. Finally, nuclear fractionation studies show cosedimentation of GRWD1 with preribosomal complexes, as well as the WD-repeat-containing protein Bop1, which has previously been implicated in ribosome biogenesis. These studies suggest that within mammalian cells GRWD1 plays a role in ribosome biogenesis and during myeloid differentiation its levels are regulated.