Microtubule-associated proteins MAP65-1 and MAP65-2 positively regulate axial cell growth in etiolated Arabidopsis hypocotyls.

The Arabidopsis thaliana MAP65-1 and MAP65-2 genes are members of the larger eukaryotic MAP65/ASE1/PRC gene family of microtubule-associated proteins. We created fluorescent protein fusions driven by native promoters that colocalized MAP65-1 and MAP65-2 to a subset of interphase microtubule bundles in all epidermal hypocotyl cells. MAP65-1 and MAP65-2 labeling was highly dynamic within microtubule bundles, showing episodes of linear extension and retraction coincident with microtubule growth and shortening. Dynamic colocalization of MAP65-1/2 with polymerizing microtubules provides in vivo evidence that plant cortical microtubules bundle through a microtubule-microtubule templating mechanism. Analysis of etiolated hypocotyl length in map65-1 and map65-2 mutants revealed a critical role for MAP65-2 in modulating axial cell growth. Double map65-1 map65-2 mutants showed significant growth retardation with no obvious cell swelling, twisting, or morphological defects. Surprisingly, interphase microtubules formed coaligned arrays transverse to the plant growth axis in dark-grown and GA(4)-treated light-grown map65-1 map65-2 mutant plants. We conclude that MAP65-1 and MAP65-2 play a critical role in the microtubule-dependent mechanism for specifying axial cell growth in the expanding hypocotyl, independent of any mechanical role in microtubule array organization.

Opioid Usage After Hallux Valgus Correction Surgery.

BACKGROUND: Given the lack of objective data on opioid use and the difficulty of addressing a patient's postoperative pain, we sought to quantify patient's narcotic use after hallux valgus surgery. The purpose of our study was to determine the average quantity and type of postoperative opioids consumed after hallux valgus surgery and to assess potential predictive factors for increased opioid consumption. METHODS: At the preoperative visit, patients were consented and completed a demographical questionnaire. Data were collected from the operative record, 2, 6, and 12-week postoperative visits. Type and number of pills prescribed were recorded as well as number of pills consumed at each postoperative visit. A logistic regression was performed to determine the average quantity consumed postoperatively and any statistically significant correlations. RESULTS: The average number of opioid pills collectively consumed at the 2-week and 12-week postoperative visit was 20 and 23, respectively. At the 2-week postoperative visit, only patient body mass index (BMI) showed a correlation with increased opioid use. CONCLUSION: Patients consumed an average of 23 of 40 (57.5%) narcotic pain pills prescribed after hallux valgus reconstruction surgery through the 12-week postoperative period. Owing to the opioid epidemic and potential for narcotic diversion, surgeons should counsel their patients on proper nonopioid postoperative pain management. LEVEL OF EVIDENCE: II Therapeutic.

Biosensors Show Promise as a Measure of Student Engagement in a Large Introductory Biology Course.

This study measured student engagement in real time through the use of skin biosensors, specifically galvanic skin response (GSR), in a large undergraduate lecture classroom. The study was conducted during an intervention in an introductory-level biology course (N = 420) in which one section of the course was taught with active-learning approaches and the other with traditional didactic teaching. GSR results were aligned and correlated with the Classroom Observation Protocol for Undergraduate STEM, or COPUS, and student self-reflections on their own engagement. Results showed that the active-learning section spent more time working in groups, resulting in GSR measures that trended higher and self-reported engagement, while showing indications of higher content learning gains compared with the traditional lecture section. Comparisons between COPUS scores and GSR readings indicate that engagement increased during group work and decreased during listening activities. Throughout a class period, GSR activity of the active-learning group showed increased trends compared with baseline measures, while the traditional lecture group showed decreased trends. Results indicate that GSR is a promising measure of real-time student engagement in the undergraduate classroom, bringing a new technique to discipline-based education researchers who aim to better measure student engagement; however, some limitations exist for broad-scale implementation.