Novel cuff design to facilitate anastomosis of small vessels during cervical heterotopic heart transplantation in rats.

Cervical heterotopic heart transplantation in rodents is a useful tool for studying transplantation immunology. However, end-to-end anastomosis of small-diameter vessels by using standard microsurgical technique is technically difficult and can require prolonged graft ischemia. A novel cuff system was designed from polyethylene tubing to allow anastomosis of vessels with internal luminal diameters of 0.3 to 0.9 mm. Key features include a spring-like adjustable lumen to facilitate vessel eversion, a barb to hold vessel ends in place after eversion, and a handling system that allows easy manipulation and stabilization of cuffs by a single operator. After a training period, a single operator performed a series of 8 transplants in which the mean warm ischemic time of grafts was 8.5 ± 2.9 min. Here we provide a detailed description of how to construct and perform end-to-end vessel anastomosis by using our novel cuff system. The discussion of the technique is supplemented with tips learned during the process of developing a reliable experimental model.

Implementation of a study skills program for entering at-risk medical students.

While the first year of medical school is challenging for all students, there may be specific issues for students from rural areas, economically disadvantaged backgrounds, ethnic minorities, or nontraditional age groups. A Summer Prematriculation Program (SPP) was created to prepare entering at-risk students for the demands of medical school. For the past 2 yr, an emphasis was placed on the development of appropriate study plans and skills. On presurveys, students predicted an increase in their number of study hours per lecture hour, from 7.6 h in undergraduate coursework to 9.1 h in medical school coursework (n = 35). These study plans were infeasible given the rigorous didactic lecture schedule in medical school. Interventions were made through lectures on study plans and modeling of appropriate study habits using engaging lectures in the SPP physiology course. At the end of the program, a postsurvey was given, and students reported a reduction in the planned hours of study to a more realistic 3.9 h of study time per hour of lecture. Furthermore, students planned to decrease their use of textbooks while increasing their use of concept mapping, videos, and peer teaching. The majority of students completing the SPP program with a study skills emphasis performed well in the Medical Physiology course, with 4 students honoring in the course, 27 students passing, and 2 students remediating the course after an initial failure. These results indicate that at-risk medical students may have inappropriate study plans that can be improved through participation in a program that emphasizes study skills development.

A comparison of professional-level faculty and student perceptions of active learning: its current use, effectiveness, and barriers.

Active learning is an instructional method in which students become engaged participants in the classroom through the use of in-class written exercises, games, problem sets, audience-response systems, debates, class discussions, etc. Despite evidence supporting the effectiveness of active learning strategies, minimal adoption of the technique has occurred in many professional programs. The goal of this study was to compare the perceptions of active learning between students who were exposed to active learning in the classroom (n = 116) and professional-level physiology faculty members (n = 9). Faculty members reported a heavy reliance on lectures and minimal use of educational games and activities, whereas students indicated that they learned best via the activities. A majority of faculty members (89%) had observed active learning in the classroom and predicted favorable effects of the method on student performance and motivation. The main reported barriers by faculty members to the adoption of active learning were a lack of necessary class time, a high comfort level with traditional lectures, and insufficient time to develop materials. Students hypothesized similar obstacles for faculty members but also associated many negative qualities with the traditional lecturers. Despite these barriers, a majority of faculty members (78%) were interested in learning more about the alternative teaching strategy. Both faculty members and students indicated that active learning should occupy portions (29% vs. 40%) of face-to-face class time.

Implementation of a laboratory quality assurance program: the Louisville experience.

Remakes, or the refabrication of dental prostheses, can occur as a result of inherent inaccuracies in both clinical and laboratory procedures. Because dental schools manage large numbers of predoctoral dental students with limited familiarity and expertise as related to clinical prosthodontic techniques, it is likely these schools will experience an elevated incidence of laboratory remakes and their ramifications. The University of Louisville School of Dentistry, not unlike other dental schools, has experienced remakes associated with both fixed and removable prosthodontic procedures. Limitations in faculty standardization and variable enforcement of established preclinical protocols have been identified as variables associated with the high percentage of remakes documented. The purpose of this study was to introduce the implementation of a new multidepartmental quality assurance program designed to increase consistency and quality in both information provided to commercial dental laboratories and the prostheses returned. The program has shown to be advantageous in terms of cost-effectiveness and treatment outcomes. A statistically significant decrease in remake percentages has been recorded from inception of this program in December 2010 until December 2012. Furthermore, this program has resulted in more consistent communication between the dental school and commercial dental laboratories, among faculty members, and between faculty and students.

A comparison of traditional and engaging lecture methods in a large, professional-level course.

In engaging lectures, also referred to as broken or interactive lectures, students are given short periods of lecture followed by "breaks" that can consist of 1-min papers, problem sets, brainstorming sessions, or open discussion. While many studies have shown positive effects when engaging lectures are used in undergraduate settings, the literature surrounding use of the learning technique for professional students is inconclusive. The novelty of this study design allowed a direct comparison of engaging physiology lectures versus didactic lecture formats in the same cohort of 120 first-year School of Dentistry DMD students. All students were taught five physiological systems using traditional lecture methods and six physiological systems using engaging lecture methods. The use of engaging lectures led to a statistically significant higher average on unit exams compared with traditional didactic lectures (8.6% higher, P < 0.05). Furthermore, students demonstrated an improved long-term retention of information via higher scores on the comprehensive final exam (22.9% higher in engaging lecture sections, P < 0.05). Many qualitative improvements were also indicated via student surveys and evaluations, including an increased perceived effectiveness of lectures, decrease in distractions during lecture, and increased confidence with the material. The development of engaging lecture activities requires a significant amount of instructor preparation and limits the time available to provide traditional lectures. However, the positive results of this study suggest the need for a restructuring of the physiology curriculum to incorporate more engaging lectures to improve both the qualitative experiences and performance levels of professional students.

Role of oxidative stress in geldanamycin-induced cytotoxicity and disruption of Hsp90 signaling complex.

Heat shock protein 90 (Hsp90) is a chaperone protein regulating PC-12 cell survival by binding and stabilizing Akt, Raf-1, and Cdc37. Hsp90 inhibitor geldanamycin (GA) cytotoxicity has been attributed to the disruption of Hsp90 binding, and the contribution of oxidative stress generated by its quinone group has not been studied in this context. Reactive oxygen species (ROS) and cell survival were assessed in PC-12 cells exposed to GA or menadione (MEN), and Akt, Raf-1, and Cdc37 expression and binding to Hsp90 were determined. GA disrupted Hsp90 binding and increased ROS production starting at 1 h, and cell death occurred at 6 h, inhibited by N-acetylcysteine (NAC) without preventing dissociation of proteins. At 24 h, NAC prevented cytotoxicity and Hsp90 complex disruption. However, MnTBAP antioxidant treatment failed to inhibit GA cytotoxicity, suggesting that NAC acts by restoring glutathione. In contrast, 24 h MEN treatment induced cytotoxicity without disrupting Hsp90 binding. GA and MEN decreased Hsp90-binding protein expression, and proteasomal inhibition prevented MEN-, but not GA-induced degradation. In conclusion, whereas MEN cytotoxicity is mediated by ROS and proteasomal degradation, GA-induced cytotoxicity requires ROS but induces Hsp90 complex dissociation and proteasome-independent protein degradation. These differences between MEN- and GA-induced cytotoxicity may allow more specific targeting of cancer cells.