Recent evidence suggests that the glucagon-like peptide-1 (GLP-1) neuronal projection to the nucleus accumbens core (NAcC) contributes to food intake control. To investigate the role of endogenous stimulation of GLP-1 receptors (GLP-1R) in NAcC, we examined the effects of the GLP-1R antagonist exendin-(9 -39) (Ex9) on meal pattern and microstructure of ingestive behavior in rats. Intra-NAcC Ex9 treatment selectively increased meal size relative to vehicle in rats consuming 0.25 M sucrose solution or sweetened condensed milk. Microstructural analysis revealed effects of NAcC Ex9 on initial lick rate and the size and duration of licking bursts in rats consuming 0.1 or 0.25 M sucrose, suggesting that blockade of NAcC GLP-1R increases palatability. Because NAcC Ex9 did not affect licking for nonnutritive saccharin (0.1%), we suggest that the presence of nutrients in the gut may be required for endogenous stimulation of NAcC GLP-1R. Consistent with this, we also found that the meal sizesuppressive effects of intragastric nutrient infusion were attenuated by NAcC delivery of Ex9 at a dose that had no effect when delivered alone. Analysis of licking patterns revealed that NAcC Ex9 did not reverse intragastric nutrient-induced suppression of burst number but rather blunted the effect of nutrient infusion on meal size primarily by increasing the size and duration of licking bursts. Together, our results suggest that NAcC Ex9 influences taste evaluation. We conclude that GLP-1 released in NAcC in response to gastrointestinal nutrients reduces the hedonic value of food. licking microstructure; palatability; satiation; glucagon-like peptide-1; nucleus accumbens GLUCAGON-LIKE PEPTIDE-1 (GLP-1) NEURONS in the hindbrain nucleus of the solitary tract (NTS) have been hypothesized to play a role in the control of food intake since it was first shown that intracerebroventricular injection of GLP-1 potently suppresses feeding (22). These neurons are activated by meal-related signals such as gastric distention (23) and receive direct vagal afferent input (13). A physiological role for brain GLP-1 is suggested by studies showing that either pharmacological blockade of GLP-1 receptors (GLP-1R) or siRNA-mediated knockdown of NTS GLP-1 expression increases food intake and body weight (16, 3). NTS GLP-1 cells project widely throughout the brain to nuclei traditionally considered important for energy homeostasis (e.g., the paraventricular nucleus of the hypothalamus) but also to nuclei associated with reward and motivation such as the ventral tegmental area and the nucleus accumbens (NAc) (1, 10, 18). Here, we focus on the role of GLP-1R in the NAc core (NAcC) subregion. We targeted the NAcC because our previous research suggests that GLP-1R in core, but not shell, affect feeding (10). Recent studies have shown that stimulation of GLP-1R in this nucleus suppresses food intake, whereas site-specific blockade of GLP-1R increases intake (1, 10). Importantly, NAcC GLP-1R stimulation does not condition a taste aversion (10), nor does it induce...

Background Eight novel virtual surgery electives (VSEs) were developed and implemented in April–May 2020 for medical students forced to continue their education remotely due to COVID-19. Methods Each VSE was 1–2 weeks long, contained specialty-specific course objectives, and included a variety of teaching modalities. Students completed a post-course survey to assess changes in their interest and understanding of the specialty. Quantitative methods were employed to analyze the results. Results Eighty-three students participated in the electives and 67 (80.7%) completed the post-course survey. Forty-six (68.7%) respondents reported “increased” or “greatly increased” interest in the course specialty completed. Survey respondents’ post-course understanding of each specialty increased by a statistically significant amount ( p -value = <0.0001). Conclusion This initial effort demonstrated that VSEs can be an effective tool for increasing medical students’ interest in and understanding of surgical specialties. They should be studied further with more rigorous methods in a larger population.

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Introduction On March 17, 2020 the AAMC recommended dismissal of medical students from clinical settings due to the COVID-19 pandemic. Third-year (M3) and fourth-year (M4) medical students were at home, M4s were interested in teaching, and residents and faculty had fewer clinical responsibilities due to elective surgery cancellations. To continue M3 access to education, we created a virtual surgery elective (VSE) that aimed to broaden students’ exposure to, and elicit interest in, general surgery (GS). Methods Faculty, surgical residents, and M4s collaborated to create a two-week VSE focusing on self-directed learning and direct interactions with surgery faculty. Each day was dedicated to a specific pathology commonly encountered in GS. A variety of teaching methods were employed including self-directed readings and videos, M4 peer lectures, case-based learning and operative video review with surgery faculty, and weekly surgical conferences. A VSE skills lab was also conducted to teach basic suturing and knot-tying. All lectures and skills labs were via Zoom videoconference (Zoom Video Communications Inc). A post-course anonymous survey sent to all participants assessed changes in their understanding of GS and their interest in GS and surgery overall. Results Fourteen M3s participated in this elective over two consecutive iterations. The survey response rate was 79%. Ninety-one percent of students believed the course met its learning objectives “well” or “very well.” Prior to the course, 27% reported a “good understanding” and 0% a “very good” understanding of GS. Post-course, 100% reported a “good” or “very good” understanding of GS, a statistically significant increase (p=0.0003). Eighty-two percent reported increased interest in GS and 64% reported an increase in pursuing GS as a career (Table 1). Conclusion As proof of concept, this online course successfully demonstrated virtual medical student education can increase student understanding of GS topics, increase interest in GS, and increase interest in careers in surgery. To broaden student exposure to GS, we plan to integrate archived portions of this course into the regular third-year surgery clerkship and these can also be used to introduce GS in the preclinical years.

A quick demonstration is described to showcase the use of CO2 as an alternative, benign dry cleaning solvent. The demonstration includes visible evidence of CO2 as a solid, a liquid, and a gas, making it ideal as part of a broader lesson on states of matter. The demonstration relies on a technique for generating liquid CO2 in a centrifuge tube, which has been used for extractions in undergraduate teaching laboratories for over a decade. This report represents a unique attempt to transfer this method to the K–8 curriculum.