Novel binary gene expression tools like the LexA-LexAop system could powerfully enhance studies of metabolism, development, and neurobiology in Drosophila. However, specific LexA drivers for neuroendocrine cells and many other developmentally relevant systems remain limited. In a unique high school biology course, we generated a LexA-based enhancer trap collection by transposon mobilization. The initial collection provides a source of novel LexA-based elements that permit targeted gene expression in the corpora cardiaca, cells central for metabolic homeostasis, and other neuroendocrine cell types. The collection further contains specific LexA drivers for stem cells and other enteric cells in the gut, and other developmentally relevant tissue types. We provide detailed analysis of nearly 100 new LexA lines, including molecular mapping of insertions, description of enhancer-driven reporter expression in larval tissues, and adult neuroendocrine cells, comparison with established enhancer trap collections and tissue specific RNAseq. Generation of this open-resource LexA collection facilitates neuroendocrine and developmental biology investigations, and shows how empowering secondary school science can achieve research and educational goals.

Background: Adolescent athletes who sustain an anterior cruciate ligament (ACL) tear have significantly reduced activity levels during recovery. Activity level is linked to body mass index (BMI); however, it is unclear how recovery from an ACL reconstruction (ACLR) affects relative BMI and whether these changes persist after return to activity. Hypothesis: Patients’ BMI percentile will significantly increase after ACLR, but will trend toward baseline after return to activity. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: A retrospective review of 666 pediatric and adolescent patients who underwent ACLR was performed. Body mass was assessed by evaluating change in BMI percentile at 8 standard-of-care time windows relative to BMI percentile at time of surgery. Linear regression and bivariate and multivariate analyses were used to assess the effect of time window and other demographic factors on the change in BMI percentile. These analyses were rerun after dividing patients by clinical obesity categorization (underweight, normal, overweight, or obese) at time of surgery to assess the effect of preinjury body mass levels. Results: BMI percentile of all BMI categories tended to increase postoperatively, peaking 6 to 9 months after surgery, with a median increase of 1.83 percentile points. After this peak, BMI approached baseline but remained elevated at 0.95 percentile points 2 years postoperatively. Beginning 3 months after surgery, the normal-weight group had significantly larger changes in BMI percentile at each time window, peaking at 4.15 points above baseline at 9 months. This BMI increase among normal-weight patients persisted in the second postoperative year, with a median percentile increase of 2.63 points. Conclusion: Pediatric and adolescent patients, especially those with a normal BMI, undergo significant changes to their BMI during recovery from ACLR. Clinical Relevance: Patients’ failure to return to their presurgical BMI percentile 2 years postoperatively suggests that ACLR may have long-reaching and often unappreciated effects on body mass.

Background: The primary goal in managing early-onset scoliosis (EOS) is delaying/preventing surgical intervention while allowing improved spinal growth and chest wall and lung development to improve life expectancy. The effectiveness of serial casting for patients with neuromuscular and syndromic EOS is unclear. Methods: Patients from 2 multicenter registries who underwent serial casting for nonidiopathic scoliosis (NIS) were reviewed retrospectively. Comparisons were made between precasting and postcasting major and compensatory curves and spine height. The need for surgical intervention and any treatment complications were documented. Risk factors for major curve progression from baseline to casting cessation were evaluated via univariate analysis. Results: Forty-four patients (23 females; 21 males) with NIS (26 syndromic, 18 neuromuscular) and a mean age of 3.2 years at baseline were included. Mean follow-up and casting duration was 3.9 and 2.0 years, respectively. There were no statistically significant differences between mean precasting and postcasting major curve (55 vs. 60 degrees; P=0.348), minor curve (31 vs. 33 degrees; P=0.510), or rib-vertebra angle difference (18 vs. 29 degrees; P=0.840). However, thoracic height (15.5 vs. 16.8 cm; P=0.031) and lumbar height (8.9 vs. 9.8 cm; P=0.013) were significantly greater upon casting cessation. Currently, 13 patients (30%) have had successful casting (improvement of major curve ≥10 degrees) while 24 patients (55%) experienced major curve progression (worsening), and 19 patients (43%) required surgical intervention. Mean time from first casting to surgery was 34.5±15.1 months. There were no statistically significant predictors for major curve progression on univariate analysis. Conclusions: Spinal deformity progression despite casting and the subsequent need for surgical intervention for NIS were significantly higher compared with those reported for idiopathic EOS. However, serial casting did afford a substantial delay in surgical intervention. Ultimately, serial casting for neuromuscular or syndromic EOS is an effective strategy for delaying surgical intervention, despite suboptimal radiographic outcomes. Level of Evidence: Level III.

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