Preclinical lentiviral vector-mediated hematopoietic stem and progenitor cell gene therapy corrects Pompe disease-related muscle and neurological manifestations.

Pompe disease, a rare genetic neuromuscular disorder, is caused by a deficiency of acid alpha-glucosidase (GAA), leading to an accumulation of glycogen in lysosomes, and resulting in the progressive development of muscle weakness. The current standard treatment, enzyme replacement therapy (ERT), is not curative and has limitations such as poor penetration into skeletal muscle and both the central and peripheral nervous systems, a risk of immune responses against the recombinant enzyme, and the requirement for high doses and frequent infusions. To overcome these limitations, lentiviral vector-mediated hematopoietic stem and progenitor cell (HSPC) gene therapy has been proposed as a next-generation approach for treating Pompe disease. This study demonstrates the potential of lentiviral HSPC gene therapy to reverse the pathological effects of Pompe disease in a preclinical mouse model. It includes a comprehensive safety assessment via integration site analysis, along with single-cell RNA sequencing analysis of central nervous tissue samples to gain insights into the underlying mechanisms of phenotype correction.

[18F]F-AraG imaging reveals association between neuroinflammation and brown- and bone marrow adipose tissue.

Brown and brown-like adipose tissues have attracted significant attention for their role in metabolism and therapeutic potential in diabetes and obesity. Despite compelling evidence of an interplay between adipocytes and lymphocytes, the involvement of these tissues in immune responses remains largely unexplored. This study explicates a newfound connection between neuroinflammation and brown- and bone marrow adipose tissue. Leveraging the use of [18F]F-AraG, a mitochondrial metabolic tracer capable of tracking activated lymphocytes and adipocytes simultaneously, we demonstrate, in models of glioblastoma and multiple sclerosis, the correlation between intracerebral immune infiltration and changes in brown- and bone marrow adipose tissue. Significantly, we show initial evidence that a neuroinflammation-adipose tissue link may also exist in humans. This study proposes the concept of an intricate immuno-neuro-adipose circuit, and highlights brown- and bone marrow adipose tissue as an intermediary in the communication between the immune and nervous systems. Understanding the interconnectedness within this circuitry may lead to advancements in the treatment and management of various conditions, including cancer, neurodegenerative diseases and metabolic disorders.

Frequent low-impact exposure to THC during adolescence causes persistent sexually dimorphic alterations in the response to viral infection in mice.

Adolescent exposure to Δ9-tetrahydrocannabinol (THC) has enduring effects on energy metabolism and immune function. Prior work showed that daily administration of a low-impact dose of THC (5 mg/kg, intraperitoneal) during adolescence alters transcription in adult microglia and disrupts their response to bacterial endotoxin or social stress. To explore the lasting impact of adolescent THC exposure on the brain's reaction to viral infection, we administered THC (5 mg/kg, intraperitoneal) in male and female mice once daily on postnatal day (PND) 30-43. When the mice reached adulthood (PND 70), we challenged them with the viral mimic, polyinosinic acid:polycytidylic acid [Poly(I:C)], and assessed sickness behavior (motor activity, body temperature) and whole brain gene transcription. Poly(I:C) caused an elevation in body temperature which was lessened by prior THC exposure in female but not male mice. Adolescent THC exposure did not affect the locomotor response to Poly(I:C) in either sex. Transcriptomic analyses showed that Poly(I:C) produced a substantial upregulation of immune-related genes in the brain, which was decreased by THC in females. Additionally, the viral mimic caused a male-selective downregulation in transcription of genes involved in neurodevelopment and synaptic transmission, which was abrogated by adolescent THC treatment. The results indicate that Poly(I:C) produces complex transcriptional alterations in the mouse brain, which are sexually dimorphic and differentially affected by early-life THC exposure. In particular, adolescent THC dampens the brain's antiviral response to Poly(I:C) in female mice and prevents the transcriptional downregulation of neuron-related genes caused by the viral mimic in male mice.

The Emmaus Project: Aging, Illness, and Dying Among Older Christians-A Qualitative Study.

Older patients have an increased risk of depression, neglect, and abuse. Studies demonstrate that spiritual and religious coping is important at times of personal crisis, but few studies explore the impact of religion on older persons' experiences of aging, illness, and impending death. This study set out to identify recurring spiritual and clinical themes shared by retirement home residents in the context of a Christian faith-based processing group. A qualitative cohort study of residents over the age of 65 was conducted at a retirement home in Chicago, Illinois. The study consisted of 8 hour-long Scripture-based processing group sessions co-led by a study researcher and the onsite chaplain. Questionnaires were administered to each group and handwritten responses were collected and analyzed to identify recurring clinical and spiritual themes. Ten participants enrolled in the group study. The questionnaire completion rate was 35% (49/140). The most recurring clinical themes included 1) events of death or terminal illness and 2) physical limitations. The most recurring spiritual themes included 1) God's presence and 2) prayer and worship. The most recurring coded theme overall was family. This study provided insight into the spiritual experiences of older Christians in one retirement home community. Increased awareness of the spiritual perspectives of the geriatric population may strengthen the doctor-patient relationship and lead to improvements in clinical care.

Adipose Tissue and Metabolic Health.

In this review, we provide a brief synopsis of the connections between adipose tissue and metabolic health and highlight some recent developments in understanding and exploiting adipocyte biology. Adipose tissue plays critical roles in the regulation of systemic glucose and lipid metabolism and secretes bioactive molecules possessing endocrine, paracrine, and autocrine functions. Dysfunctional adipose tissue has a detrimental impact on metabolic health and is intimately involved in key aspects of metabolic diseases such as insulin resistance, lipid overload, inflammation, and organelle stress. Differences in the distribution of fat depots and adipose characteristics relate to divergent degrees of metabolic dysfunction found in metabolically healthy and unhealthy obese individuals. Thermogenic adipocytes increase energy expenditure via mitochondrial uncoupling or adenosine triphosphate-consuming futile substrate cycles, while functioning as a metabolic sink and participating in crosstalk with other metabolic organs. Manipulation of adipose tissue provides a wealth of opportunities to intervene and combat the progression of associated metabolic diseases. We discuss current treatment modalities for obesity including incretin hormone analogs and touch upon emerging strategies with therapeutic potential including exosome-based therapy, pharmacological activation of brown and beige adipocyte thermogenesis, and administration or inhibition of adipocyte-derived factors.

Practical wisdom in medicine through the eyes of medical students and physicians.

BACKGROUND: Practical wisdom is considered a multidimensional virtue of enduring relevance to medicine. Though it has received increasing attention in recent years, proposed frameworks for practical wisdom can differ, and little is known about how medical students and physicians describe its dimensions and relevance. METHODS: We used structured interviews, employing open-ended and closed-ended questions, to describe how medical students and physicians understand practical wisdom and identify the kinds of clinical situations they believe require practical wisdom. We interviewed 102 participants at two US medical schools in 2021, comprising a voluntary response sample of 40 pre-clinical medical students and 40 clinical medical students and a purposive sample of 22 nominated physicians. Interviews were conducted by videoconference using a structured interview guide. Open-ended responses were coded using qualitative content analysis (directed and conventional) and tabulated; closed-ended responses were tabulated. Quotations provided qualitative illustrations, and frequencies were used for summative results. RESULTS: Participants considered practical wisdom clinically meaningful, broadly relevant and multidimensional. Most described it as deliberative, goal-directed, context-sensitive, integrated with ethics and marked by integrity and motivation to act. Many described it as experience-based, person-centred or problem-solving. Participants also selected an average of 15.6 (SD = 4.9) additional virtues as being essential for practical wisdom in medicine and described a broad range of clinical situations that require practical wisdom in medicine. CONCLUSIONS: Participants described practical wisdom as a multidimensional capacity that entails deliberation, depends on a constellation of other virtues and is broadly applicable to medicine. Most agreed it is goal-directed and context-sensitive and involves ethics, integrity and motivation. Efforts to teach practical wisdom in medical education should clarify its dimensions and highlight its relationship to virtue ethics, professionalism, clinical judgement and the individualised care of patients as persons.

The Enhancing Life Research Laboratory: Tools for Addressing Orientational Distress in the Medical Profession.

PURPOSE: To explore distress in the medical profession and how it was highlighted by the ongoing COVID-19 pandemic. The term "orientational distress" was developed to name the experience of a breakdown in the patterns of moral self-understanding and one's capacity to navigate professional responsibilities. METHOD: The Enhancing Life Research Laboratory at the University of Chicago convened a 5-session online workshop (total 10 hours, May-June 2021) to explore orientational distress and to promote collaboration between academics and physicians. Sixteen participants from Canada, Germany, Israel, and the United States engaged in discussions of the conceptual framework and toolkit to address orientational distress within institutional settings. The tools included 5 dimensions of life, 12 dynamics of life, and the role of counterworlds. Follow-up narrative interviews were transcribed and coded using a consensus-based iterative process. RESULTS: Participants reported that the concept of orientational distress helped explain their professional experiences better than burnout or moral distress. Moreover, participants strongly endorsed the project's supporting thesis that collaborative work on orientational distress and the tools provided in the research laboratory had a specific intrinsic value and provided benefits not found in other support instruments. CONCLUSIONS: Orientational distress compromises medical professionals and threatens the medical system. Next steps include the dissemination of materials from the Enhancing Life Research Laboratory to more medical professionals and medical schools. In contrast to burnout and moral injury, the concept of orientational distress may better enable clinicians to understand and more fruitfully navigate the challenges of their professional situations.

Regulation of beige adipocyte thermogenesis by the cold-repressed ER protein NNAT.

OBJECTIVE: Cold stimuli trigger the conversion of white adipose tissue into beige adipose tissue, which is capable of non-shivering thermogenesis. However, what process drives this activation of thermogenesis in beige fat is not well understood. Here, we examine the ER protein NNAT as a regulator of thermogenesis in adipose tissue. METHODS: We investigated the regulation of adipose tissue NNAT expression in response to changes in ambient temperature. We also evaluated the functional role of NNAT in thermogenic regulation using Nnat null mice and primary adipocytes that lack or overexpress NNAT. RESULTS: Cold exposure or treatment with a ß3-adrenergic agonist reduces the expression of adipose tissue NNAT in mice. Genetic disruption of Nnat in mice enhances inguinal adipose tissue thermogenesis. Nnat null mice exhibit improved cold tolerance both in the presence and absence of UCP1. Gain-of-function studies indicate that ectopic expression of Nnat abolishes adrenergic receptor-mediated respiration in beige adipocytes. NNAT physically interacts with the ER Ca2+-ATPase (SERCA) in adipocytes and inhibits its activity, impairing Ca2+ transport and heat dissipation. We further demonstrate that NHLRC1, an E3 ubiquitin protein ligase implicated in proteasomal degradation of NNAT, is induced by cold exposure or ß3-adrenergic stimulation, thus providing regulatory control at the protein level. This serves to link cold stimuli to NNAT degradation in adipose tissue, which in turn leads to enhanced SERCA activity. CONCLUSIONS: Our study implicates NNAT in the regulation of adipocyte thermogenesis.

CFTR regulates brown adipocyte thermogenesis via the cAMP/PKA signaling pathway.

BACKGROUND: Cystic fibrosis (CF) is characterized by reduced growth and lower body weight, which are multifactorial. CF mouse models lack key disease characteristics that predispose to a negative energy balance, such as pulmonary infections or exocrine pancreatic insufficiency, and yet they still exhibit a growth defect and an abnormally increased energy expenditure. Whether adipocyte thermogenesis contributes to the elevated resting energy expenditure in CF mice is unknown. METHODS: We examined the expression of CFTR in thermogenic brown adipose tissue (BAT) and investigated a functional role for CFTR using BAT-specific CFTR null mice (CFTRBATKO). RESULTS: The CFTR protein is expressed in mouse BAT at levels comparable to those in the lungs. BAT-specific inactivation of CFTR in mice increases whole-body energy expenditure associated with sympathetic stimulation by cold exposure. Weight gain on a high-fat diet is attenuated in these mice. However, CFTR-deficient brown adipocytes themselves have impaired, rather than enhanced, thermogenic responses. These cells feature decreased lipolysis and blunted activation of the cAMP/PKA signaling pathway in response to adrenergic stimulation. This suggests that compensatory heat production in other tissues likely accounts for the increased systemic energy expenditure seen in CFTRBATKO mice. CONCLUSIONS: Our data reveal a new role for CFTR in the regulation of adipocyte thermogenesis.

Screening chimeric GAA variants in preclinical study results in hematopoietic stem cell gene therapy candidate vectors for Pompe disease.

Pompe disease is a rare genetic neuromuscular disorder caused by acid α-glucosidase (GAA) deficiency resulting in lysosomal glycogen accumulation and progressive myopathy. Enzyme replacement therapy, the current standard of care, penetrates poorly into the skeletal muscles and the peripheral and central nervous system (CNS), risks recombinant enzyme immunogenicity, and requires high doses and frequent infusions. Lentiviral vector-mediated hematopoietic stem and progenitor cell (HSPC) gene therapy was investigated in a Pompe mouse model using a clinically relevant promoter driving nine engineered GAA coding sequences incorporating distinct peptide tags and codon optimizations. Vectors solely including glycosylation-independent lysosomal targeting tags enhanced secretion and improved reduction of glycogen, myofiber, and CNS vacuolation in key tissues, although GAA enzyme activity and protein was consistently lower compared with native GAA. Genetically modified microglial cells in brains were detected at low levels but provided robust phenotypic correction. Furthermore, an amino acid substitution introduced in the tag reduced insulin receptor-mediated signaling with no evidence of an effect on blood glucose levels in Pompe mice. This study demonstrated the therapeutic potential of lentiviral HSPC gene therapy exploiting optimized GAA tagged coding sequences to reverse Pompe disease pathology in a preclinical mouse model, providing promising vector candidates for further investigation.

Sustaining the Intrinsic Motivations of the "Good Physician": A Content Analysis of Medical Students' and Physicians' Responses from Two National Surveys.

OBJECTIVE: Physician motivation has been described as the reason, purpose, and force that drives people to pursue their work, and motivating factors include those that are intrinsic or extrinsic to the work. Social forces may contribute to motivational disparities between medical school and actual practice. METHODS: A secondary data analysis of two national surveys (medical students and practicing physicians from various specialties) was conducted. Content analysis was performed on open-ended survey items that elicited students' and physicians' responses to meaningful experiences in medicine. RESULTS: In the medical student sample, four themes were identified as factors intrinsic to medicine: role models, clinical experiences, patient interactions, and peer interactions. In total, intrinsic factors comprised 86.5% (193/208) of coded responses. In the practicing physician sample, five themes were identified as factors intrinsic to medicine: difficult patient interactions, conflict with colleagues or staff, meaningful patient interactions, involvement in medical education-research-academia, and medicine as a calling/mission. In total, intrinsic factors comprised 24.0% (140/582) of coded responses. CONCLUSIONS: Our findings suggest that the reality of social forces in medicine threatens the ability of practicing physicians to derive meaning from their work, although students and physicians still report intrinsic motivation from establishing meaningful relationships. Further research is needed to explore what strategies enable physicians to wisely navigate the dynamic interactions of intrinsic and extrinsic motivators over various stages of their careers. These strategies could include encouraging reflective spaces in physicians' workplaces that have a specific focus on sustaining intrinsic motivation in medicine.

High-throughput analysis of hematopoietic stem cell engraftment after intravenous and intracerebroventricular dosing.

Hematopoietic stem/progenitor cell gene therapy (HSPC-GT) has shown clear neurological benefit in rare diseases, which is achieved through the engraftment of genetically modified microglia-like cells (MLCs) in the brain. Still, the engraftment dynamics and the nature of engineered MLCs, as well as their potential use in common neurogenerative diseases, have remained largely unexplored. Here, we comprehensively characterized how different routes of administration affect the biodistribution of genetically engineered MLCs and other HSPC derivatives in mice. We generated a high-resolution single-cell transcriptional map of MLCs and discovered that they could clearly be distinguished from macrophages as well as from resident microglia by the expression of a specific gene signature that is reflective of their HSPC ontogeny and irrespective of their long-term engraftment history. Lastly, using murine models of Parkinson's disease and frontotemporal dementia, we demonstrated that MLCs can deliver therapeutically relevant levels of transgenic protein to the brain, thereby opening avenues for the clinical translation of HSPC-GT to the treatment of major neurological diseases.

Adipose Mitochondrial Complex I Deficiency Modulates Inflammation and Glucose Homeostasis in a Sex-Dependent Manner.

Mitochondrial dysfunction in adipose tissue has been associated with type 2 diabetes, but it is unclear whether it is a cause or the consequence. Mitochondrial complex I is a major site of reactive oxygen species generation and a therapeutic target. Here we report that genetic deletion of the complex I subunit Ndufs4 specifically in adipose tissue results in an increased propensity to develop diet-induced weight gain, glucose intolerance, and elevated levels of fat inflammatory genes. This outcome is apparent in young males but not in young females, suggesting that females are relatively protected from the adverse consequences of adipose mitochondrial dysfunction for metabolic health. Mutant mice of both sexes exhibit defects in brown adipose tissue thermogenesis. Fibroblast growth factor 21 (FGF21) signaling in adipose tissue is selectively blunted in male mutant mice relative to wild-type littermates, consistent with sex-dependent regulation of its autocrine/paracrine action in adipocytes. Together, these findings support that adipocyte-specific mitochondrial dysfunction is sufficient to induce tissue inflammation and can cause systemic glucose abnormalities in male mice.

Moral Elevation, Physician Role Models, and Selected Markers of Professional Identity Formation and Well-Being: A Secondary Analysis from Two National Surveys.

OBJECTIVES: Moral elevation is the underlying emotion that arises when witnessing admirable acts, and it is theorized to be the psychological mechanism driving the impact that positive clinical role models have on medical students' professional identity formation (eg, growth in professional virtues, higher sense of meaning, and well-being). This proof-of-concept study explores the development of the Moral Elevation Scale in Medicine by testing the association of moral elevation with various markers of professional identity formation. METHODS: A secondary data analysis of two nationally representative samples of 960 medical students and 2000 physicians was performed. Respondents completed validated measures of moral elevation as well as markers of professional identity formation, including patient-centered virtues (empathic compassion, interpersonal generosity, mindfulness) and measures of well-being (life meaning, life satisfaction, spirituality, burnout). RESULTS: The study obtained adjusted response rates of 56.2% (1047/1863, physician survey) and 48.7% (448/919, student survey). The national estimates for mean moral elevation in medical students and physicians are 4.34/5.00 and 4.22/5.00, respectively. In medical students and physicians, high moral elevation was associated with higher empathic compassion (student odds ratio [OR] 1.30, 95% confidence interval [CI] 1.02-1.67; physician OR 1.22, 95% CI 1.23-1.65) and, similarly, generosity. In addition, higher moral elevation in the physician cohort was associated with greater life meaning (OR 2.03, 95% CI 1.25-3.32) and similarly spirituality. CONCLUSIONS: In medical students and practicing physicians, self-reported experiences of high moral elevation with physician role models were associated with higher self-reported measures of patient-centered virtues, spirituality, and life meaning. Our Moral Elevation Scale in Medicine demonstrates preliminary promise as a measure to assess environmental precursors needed for virtue development in professional identity formation, but further reliability and validity testing of this measure is needed.

Gene Therapy Developments for Pompe Disease.

Pompe disease is an inherited neuromuscular disorder caused by deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). The most severe form is infantile-onset Pompe disease, presenting shortly after birth with symptoms of cardiomyopathy, respiratory failure and skeletal muscle weakness. Late-onset Pompe disease is characterized by a slower disease progression, primarily affecting skeletal muscles. Despite recent advancements in enzyme replacement therapy management several limitations remain using this therapeutic approach, including risks of immunogenicity complications, inability to penetrate CNS tissue, and the need for life-long therapy. The next wave of promising single therapy interventions involves gene therapies, which are entering into a clinical translational stage. Both adeno-associated virus (AAV) vectors and lentiviral vector (LV)-mediated hematopoietic stem and progenitor (HSPC) gene therapy have the potential to provide effective therapy for this multisystemic disorder. Optimization of viral vector designs, providing tissue-specific expression and GAA protein modifications to enhance secretion and uptake has resulted in improved preclinical efficacy and safety data. In this review, we highlight gene therapy developments, in particular, AAV and LV HSPC-mediated gene therapy technologies, to potentially address all components of the neuromuscular associated Pompe disease pathology.

Defective brown adipose tissue thermogenesis and impaired glucose metabolism in mice lacking Letmd1.

Manipulation of energy-dissipating adipocytes has the potential to produce metabolic benefits. To this end, it is valuable to understand the mechanisms controlling the generation and function of thermogenic fat. Here, we identify Letm1 domain containing 1 (Letmd1) as a regulator of brown fat formation and function. The expression of Letmd1 is induced in brown fat by cold exposure and by ß-adrenergic activation. Letmd1-deficient mice exhibit severe cold intolerance concomitant with abnormal brown fat morphology, reduced thermogenic gene expression, and low mitochondrial content. The null mice exhibit impaired ß3-adrenoreceptor-dependent thermogenesis and are prone to diet-induced obesity and defective glucose disposal. Letmd1 was previously described as a mitochondrial protein, and we find that it also localizes to the nucleus and interacts with the transcriptional coregulator and chromatin remodeler Brg1/Smarca4, thus providing a way to impact thermogenic gene expression. Our study uncovers a role for Letmd1 as a key regulatory component of adaptive thermogenesis.

Association of Intrinsic Motivating Factors and Joy in Practice: A National Physician Survey.

OBJECTIVES: In response to the need to identify positive measures that more accurately describe physician wellness, this study seeks to assess the validity of a novel joy in practice measure using validated physician well-being measures and test its association with certain intrinsic and extrinsic motivators. METHODS: Secondary data analysis using a nationally representative dataset of 2000 US physicians, fielded October-December 2011. Multivariable logistic models with survey design provided nationally representative individual-level estimates. Primary outcome variables included joy in practice (enthusiasm, fulfillment, and clinical stamina in an after-hours setting). Secondary outcomes were validated measures of physician well-being such as job and life satisfaction and life meaning. Primary explanatory variables were sense of calling, number of personally rewarding hours per day, long-term relationships with patients, and burnout. RESULTS: The survey response rate was 64.5% (1289/2000). Physicians who demonstrated joy in practice were most likely to report high life satisfaction (odds ratio [OR] 2.75, 95% confidence interval [CI] 1.52-4.98) and high life meaning (OR 2.62, 95% CI 1.41-4.85). Joy in practice was strongly associated with having a sense of calling (OR 10.8, 95% CI 2.21-52.8) and ≥ 7.5 personally rewarding hours per day (OR 3.75, 95% CI 1.51-9.36); meanwhile, it was negatively associated with burnout (OR 0.26, 95% CI 0.14-0.51). Extrinsic factors such as specialty, practice setting, and annual income were not significantly associated with joy in practice in most regressions. CONCLUSIONS: The joy in practice measure shows preliminary promise as a positive marker of well-being, highlighting the need for future interventions that support physicians' intrinsic motivators and foster joy in one's practice.

HIV proviral DNA integration can drive T cell growth ex vivo.

In vivo clonal expansion of HIV-infected T cells is an important mechanism of viral persistence. In some cases, clonal expansion is driven by HIV proviral DNA integrated into one of a handful of genes. To investigate this phenomenon in vitro, we infected primary CD4+ T cells with an HIV construct expressing GFP and, after nearly 2 mo of culture and multiple rounds of activation, analyzed the resulting integration site distribution. In each of three replicates from each of two donors, we detected large clusters of integration sites with multiple breakpoints, implying clonal selection. These clusters all mapped to a narrow region within the STAT3 gene. The presence of hybrid transcripts splicing HIV to STAT3 sequences supports a model of LTR-driven STAT3 overexpression as a driver of preferential growth. Thus, HIV integration patterns linked to selective T cell outgrowth can be reproduced in cell culture. The single report of an HIV provirus in a case of AIDS-associated B-cell lymphoma with an HIV provirus in the same part of STAT3 also has implications for HIV-induced malignancy.

"Can virtue be taught?": a content analysis of medical students' opinions of the professional and ethical challenges to their professional identity formation.

BACKGROUND: Efforts have begun to characterize the ethical and professional issues encountered by medical students in their clinical years. By applying previously identified taxonomies to a national sample of medical students, this study seeks to develop generalizable insights that can inform professional identity formation across various clerkships and medical institutions. METHODS: In a national survey of medical students, participants answered an open-ended survey item that asked them to describe a clinical experience involving an ethical or professional issue. We conducted a content analysis with these responses using the Kaldjian taxonomy of ethical and professionalism themes in medical education through an iterative, consensus-building process. Noting the emerging virtues-based approach to ethics and professionalism, we also reexamined the data using a taxonomy of virtues. RESULTS: The response rate to this survey item was 144 out of 499 eligible respondents (28.9%). All 144 responses were successfully coded under one or more themes in the original taxonomy of ethical and professional issues, resulting in a total of 173 coded responses. Professional duties was the most frequently coded theme (29.2%), followed by Communication (26.4%), Quality of care (18.8%), Student-specific issues of moral distress (16.7%), Decisions regarding treatment (16.0%), and Justice (13.2%). In the virtues taxonomy, 180 total responses were coded from the 144 original responses, and the most frequent virtue coded was Wisdom (23.6%), followed by Respectfulness (20.1%) and Compassion or Empathy (13.9%). CONCLUSIONS: Originally developed from students' clinical experiences in one institution, the Kaldjian taxonomy appears to serve as a useful analytical framework for categorizing a variety of clinical experiences faced by a national sample of medical students. This study also supports the development of virtue-based programs that focus on cultivating the virtue of wisdom in the practice of medicine.