Salivary α-amylase copy number is not associated with weight trajectories and glycemic improvements following clinical weight loss: results from a 2-phase dietary intervention study.

BACKGROUND: Several studies recently reported contradicting results regarding the link between amylase 1 (AMY1) copy numbers (CNs), obesity, and type 2 diabetes. OBJECTIVE: The aim of this study was to assess the impact of AMY1 CN on anthropometrics and glycemic outcomes in obese individuals following a 2-phase dietary weight loss intervention. METHODS: Using the paralog ratio test, AMY1 CNs were accurately measured in 761 obese individuals from the DiOGenes study. Subjects first underwent an 8-wk low-calorie diet (LCD, at 800 kcal/d) and then were randomly assigned to a 6-mo weight maintenance dietary (WMD) intervention with arms having different glycemic loads. RESULTS: At baseline, a modest association between AMY1 CN and BMI (P = 0.04) was observed. AMY1 CN was not associated with baseline glycemic variables. In addition, AMY1 CN was not associated with anthropometric or glycemic outcomes following either LCD or WMD. Interaction analyses between AMY1 CN and nutrient intake did not reveal any significant association with clinical parameters (at baseline and following LCD or WMD) or when testing gene × WMD interactions during the WMD phase. CONCLUSION: In the absence of association with weight trajectories or glycemic improvements, the AMY1 CN cannot be considered as an important biomarker for response to a clinical weight loss and weight maintenance programs in overweight/obese subjects. This trial was registered at www.clinicaltrials.gov as NCT00390637.

Genome-wide gene-based analyses of weight loss interventions identify a potential role for NKX6.3 in metabolism.

Hundreds of genetic variants have been associated with Body Mass Index (BMI) through genome-wide association studies (GWAS) using observational cohorts. However, the genetic contribution to efficient weight loss in response to dietary intervention remains unknown. We perform a GWAS in two large low-caloric diet intervention cohorts of obese participants. Two loci close to NKX6.3/MIR486 and RBSG4 are identified in the Canadian discovery cohort (n = 1166) and replicated in the DiOGenes cohort (n = 789). Modulation of HGTX (NKX6.3 ortholog) levels in Drosophila melanogaster leads to significantly altered triglyceride levels. Additional tissue-specific experiments demonstrate an action through the oenocytes, fly hepatocyte-like cells that regulate lipid metabolism. Our results identify genetic variants associated with the efficacy of weight loss in obese subjects and identify a role for NKX6.3 in lipid metabolism, and thereby possibly weight control.

Eight-year outcomes of a competency-based residency training program in orthopedic surgery.

Background: The Division of Orthopaedic Surgery at the University of Toronto implemented a pilot residency training program that used a competency-based framework in July of 2009. The competency-based curriculum (CBC) deployed an innovative, modularized approach that dramatically intensified both the structured learning elements and the assessment processes. Methods: This paper discusses the initial curriculum design of the CBC pilot program; the refinement of the curriculum using curriculum mapping that allowed for efficiencies in educational delivery; details of evaluating resident competence; feedback from external reviews by accrediting bodies; and trainee and program outcomes for the first eight years of the program's implementation. Results: Feedback from the residents, the faculty, and the postgraduate residency training accreditation bodies on the CBC has been positive and suggests that the essential framework of the program may provide a valuable tool to other programs that are contemplating embarking on transition to competency-based education. Conclusions: While the goal of the program was not to shorten training per se, efficiencies gained through a modular, competency-based program have resulted in shortened time to completion of residency training for some learners.

Student-led learning: a new teaching paradigm for surgical skills.

BACKGROUND: Competency-based education and simulation are being used more frequently in surgical skills curricula. We explored a novel student-led learning paradigm, which allows trainees to become more active participants in the learning process while maintaining expert guidance and supervision. METHODS: Twelve first-year orthopedic residents were randomized to either a student-led (SL) or a traditional instructor-led group during an intensive, month-long, laboratory-based technical skills training course. A rigorous qualitative-description approach was used for analysis. RESULTS: Four prominent themes emerged: instructional style, feedback, peer and instructor collaboration, and self-efficacy. Compared with the instructor-led group, there was more peer assistance, feedback, collaboration, and hands-on and active learning observed in the SL group. CONCLUSIONS: The flexible and socially rich nature of the SL learning environment may aid in development of both technical and nontechnical skills early in residency and ultimately privilege later clinical learning.

Toronto orthopaedic boot camp III: examining the efficacy of student-regulated learning during an intensive, laboratory-based surgical skills course.

BACKGROUND: Previous studies have presented compelling data that a 1-month "boot-camp"-style course can be a highly effective mechanism for teaching and developing targeted technical skills. In the current study, we examine whether performance of these targeted skills is improved when residents are trained using directed, student-led (SL) learning methods compared with traditional instructor-led (IL) learning methods. METHODS: Twelve first-year orthopedic residents began their training with a 1-month, intensive skills course. Six residents were taught basic surgical skills using a format that focused on deliberate, SL exploration and practice of the skills under instructor supervision (SL group). The remaining residents were taught the same surgical skills using more traditional IL methods that included complete demonstration of the surgical task by an orthopedic surgeon, followed by an extended period of instruction (IL group). Performance on 4 targeted technical skills (sawing, bone drilling, suturing, and plaster splint application) was tested using an objective, structured assessment of technical skills examination for the 2 groups at the beginning and the end of the skills course. RESULTS: Before the start of the skills course, there were no differences in performance scores between the 2 groups. On completion of the skills course, mean global rating scores for the 4 surgical skills tasks were greater for the SL group compared with the IL group: SL, 3.95 ± 0.1; IL, 3.42 ± 0.1; F(1,10) = 7.66 P < .02. A similar pattern of results was revealed by the checklists scores, with the SL group outperforming the IL group: SL, 94.9 ± 2.1; IL, 86.4 ± 2.1; F(1,10) = 8.512; P < .02. CONCLUSION: Previous work has demonstrated the effectiveness of teaching basic surgical skills through an intensive course at the onset of residency. The present study shows that allowing surgical trainees to take a directed, student-regulated approach to learning basic surgical skills can further improve performance of these skills.

Sex differences in childhood sexual abuse and suicide-related behaviors.

Child sexual abuse and suicide-related behaviors are associated, but it remains unclear if the strength of this association differs in boys and girls. In a systematic review of this association in children and youth, we identified 16 relevant studies, all cross-sectional surveys of students. The association is stronger in boys specific to suicide attempt(s). Adjustments for potential confounding variables explained some, but not all of this sex difference. While additional research would strengthen causal inferences, this sex difference may be influenced by the nature and timing of child sexual abuse as well as the sex of the perpetrator, which in turn shapes the disclosure of these events.