Chronic Oral Capsaicin Exposure During Development Leads to Adult Rats with Reduced Taste Bud Volumes

Introduction A cross-sensory interaction between gustatory and trigeminal nerves occurs in the anterior tongue. Surgical manipulations have demonstrated that the strength of this relationship varies across development. Capsaicin is a neurotoxin that affects fibers of the somatosensory lingual nerve surrounding taste buds, but not fibers of the gustatory chorda tympani nerve which synapse with taste receptor cells. Since capsaicin is commonly consumed by many species, including humans, the experimental use of this neurotoxin provides a naturalistic perturbation of the lingual trigeminal system. Neonatal or adult rats consumed oral capsaicin for 40 days, and we examined the cross-sensory effect on the morphology of taste buds across development. Methods Rats received moderate doses of oral capsaicin, with chronic treatments occurring either before or after taste system maturation. Tongue morphology was examined either 2 or 50 days after treatment cessation. Edema, which has been previously suggested as a cause of changes in capsaicin-related gustatory function, was also assessed. Results Reductions in taste bud volume occurred 50 days, but not 2 days post-treatment for rats treated as neonates. Adult rats at either time post-treatment were unaffected. Edema was not found to occur with the 5 ppm concentration of capsaicin we used. Conclusions Results further elucidate the cooperative relationship between these discrete sensory systems and highlight the developmentally mediated aspect of this interaction. Implications Chronic exposure to even moderate levels of noxious stimuli during development has the ability to impact the orosensory environment, and these changes may not be evident until long after exposure has ceased

Regenerative Failure Following Rat Neonatal Chorda Tympani Transection is Associated with Geniculate Ganglion Cell Loss and Terminal Field Plasticity in the Nucleus of the Solitary Tract

Neural insult during development results in recovery outcomes that vary dependent upon the system under investigation. Nerve regeneration does not occur if the rat gustatory chorda tympani nerve is sectioned (CTX) during neonatal (≤P10) development. It is unclear how chorda tympani soma and terminal fields are affected after neonatal CTX. The current study determined the impact of neonatal CTX on chorda tympani neurons and brainstem gustatory terminal fields. To assess terminal field volume in the nucleus of the solitary tract (NTS), rats received CTX at P5 or P10 followed by chorda tympani label, or glossopharyngeal (GL) and greater superficial petrosal (GSP) label as adults. In another group of animals, terminal field volumes and numbers of chorda tympani neurons in the geniculate ganglion (GG) were determined by labeling the chorda tympani with DiI at the time of CTX in neonatal (P5) and adult (P50) rats. There was a greater loss of chorda tympani neurons following P5 CTX compared to adult denervation. Chorda tympani terminal field volume was dramatically reduced 50 days after P5 or P10 CTX. Lack of nerve regeneration after neonatal CTX is not caused by ganglion cell death alone, as approximately 30% of chorda tympani neurons survived into adulthood. Although the total field volume of intact gustatory nerves was not altered, the GSP volume and GSP-GL overlap increased in the dorsal NTS after CTX at P5, but not P10, demonstrating age-dependent plasticity. Our findings indicate that the developing gustatory system is highly plastic and simultaneously vulnerable to injury

Establishing an Institution-Wide Graduate Medical Education Research Collaborative to Promote Scholarly Activities among House Officers

Background: House officers’ ability to participate in research and quality improvement projects can be hindered by barriers, including lack of time, mentoring, and resources. Objective: Create a collaborative for house officers that provides readily accessible resources in study design as well as data collection, analysis, interpretation, and presentation. Methods: In 2017, we established a collaborative comprised of biostatisticians and an Associate Dean for Graduate Medical Research, providing a trove of experience in research and quality improvement. We worked closely with the Institutional Review Board and Electronic Health Records Core to simplify the process for house officers to utilize these research resources. The collaborative has weekly small group meetings to discuss new projects/updates and monthly large group meetings where house officers can present their ideas for additional feedback from peers and additional faculty. These formats are flexible, which allows us to tailor our assistance to the needs of each individual project. Results: In the first year since establishing the collaborative, we have received 51 project concepts from 44 house officers. Of the projects needing assistance (n=44), 100% were discussed in one of our weekly meetings and received assistance from the collaborative, and 34% presented at our large monthly meeting. A year into the collaborative, 20% of projects are either in the data analysis phase or have already been presented. Conclusion: As evidenced by the number of projects we received in our first year, there is a significant benefit for this type of collaborative resource to support and stimulate successful scholarly activity in house officers

Effective eModule Design for First-Year Medical Student Anatomy Curricula

Introduction: It is critical to evaluate student experience with any newly integrated educational resource. In 2018, a Distal Upper Limb (DUL) Anatomy eModule was developed for first-year medical students at the University of Nebraska Medical Center, who have historically identified the DUL as a region of difficulty. This mixed methods study sought to (1) evaluate learner perception of the eModule relative to other resources, and (2) identify eModule content and features that students found valuable. Methods: The DUL eModule was made available to first-year medical students in 2019 (n= 132), 2020 (n=131), and 2021 (n=131) as a voluntary, supplemental resource. In 2019-2021, all eModule users were prompted to complete a post-eModule, pre-exam survey. In 2021, users were also asked to complete a post-eModule, post-exam survey. Both surveys included a combination of Likert-type and free-response questions. Results: In the post-eModule, pre-exam survey, a majority of students from all three years agreed or strongly agreed that the eModule was convenient, preferred compared to a textbook or didactic lecture, and applicable to the gross anatomy lab, though opinions were more split when comparing the eModule to studying from a gross specimen. In the post-eModule, post-exam survey, greater than 75% of students agreed or strongly agreed that the eModule prepared them to answer DUL exam questions, and was a useful adjunct to learning DUL anatomy. In the survey’s free response section, students cited support for the eModule’s cadaveric images, its ability to consolidate/organize information, and its two modes of use, though users reported a need for a figure legend to orient the user, and a desire for a learning evaluation integrated within the eModule. Discussion: While gross anatomy has historically been taught through in-person dissection, student demand for digital, remote learning resources is certain to grow. The findings of this mixed methods analysis will serve to guide anatomy faculty in developing effective digital resources for future novice anatomists.https://digitalcommons.unmc.edu/emet_posters/1034/thumbnail.jp

Alcohol Consumption is associated with Increased CEA Levels in Male Patients with Stage IV Colorectal Cancer- A Single-Institution Retrospective Analysis

Introduction: Alcohol use is an independent risk factor for liver metastasis, a major cause of morbidity and mortality in colorectal cancer (CRC) patients. Serum CEA level is an established prognostic indicator in CRC, yet the correlation with behavioral factors such as alcohol use remains to be defined. In a single-center review, we evaluated alcohol use, gender, and CEA levels in predicting advanced disease in CRC patients. Methods: Retrospective analysis of UNMC patients diagnosed with CRC as the primary cancer between 2012-2019, stages I-IV, and age \u3e19 with documentation of alcohol use. Univariable statistics were performed using Chi-Square and non-parametric tests. Associations between stage, gender, and alcohol use (some vs. none) and the log-transformed CEA outcome (either initial or rate of change) were assessed using linear regressions. Results: Alcohol use was found to be reported in 333 of 1243 CRC patients. The cohort was comprised of 192 male and 141 female subjects. Elevated CEA levels at CRC diagnosis were associated with increased all-cause mortality (33.0% for CEA \u3e 3.4ng/ml vs 10.4% for CEA \u3c 3.4ng/ml). Model analysis found that stage IV male alcohol users showed an increase in serial CEA levels compared to males who did not use alcohol, but this pattern was not observed among stage IV females. Conclusions: Males with a history of alcohol use may be at risk for advanced CRC disease suggesting the utility of serial serum CEA monitoring in these patients. A detailed alcohol use history should be obtained in all patients with CRC as it has prognostic value and may allow for early intervention. This analysis was limited by missing alcohol use data for the majority (73.2%) of CRC patients evaluated. A prospective study is warranted to define the implications of alcohol use and risk of CRC liver metastasis

Assessing the Educational Quality of Training Videos for Collection of a Nasopharyngeal Swab

Introduction: The SARS-CoV-2 pandemic has forced healthcare systems to disseminate their training materials quickly and broadly, including instruction on identifying cases of infection through correct nasopharyngeal swabbing. Incorrect nasopharyngeal swabbing technique leads to substandard sampling, patient discomfort, and increased risk of complications. We set out to evaluate the quality of educational videos on the nasopharyngeal swab procedure. Methods: Using video search engines, videos on nasopharyngeal swabbing were identified and distributed to two reviewers. The quality of videos was assessed using a scoring system that examined indications, contraindications, personal protective equipment use, swab depth, swab angle, and audiovisual quality. Descriptive statistics and Spearman’s correlation coefficients were utilized to analyze video quality and its association with individual video characteristics. Results: Videos received an average composite score of 5.4 (range: 0-10), with about half of all videos properly discussing and demonstrating the nasopharyngeal swab technique. Over 62% of reviews indicated that the reviewer would not recommend the video to a trainee, with the vast majority identifying improper swab technique as the main factor. There were no statistically significant associations between video score and publication date, number of views, and subscribers to the publisher. Conclusion: Our study shows a glaring lack of quality educational videos on the nasopharyngeal swab procedure. Health care providers should be cautious when using educational videos to learn procedures as popularity may not be associated with accuracy