Widespread Receptivity to Neuropeptide PDF throughout the Neuronal Circadian Clock Network of Drosophila Revealed by Real-Time Cyclic AMP Imaging

SummaryThe neuropeptide PDF is released by sixteen clock neurons in Drosophila and helps maintain circadian activity rhythms by coordinating a network of ∼150 neuronal clocks. Whether PDF acts directly on elements of this neural network remains unknown. We address this question by adapting Epac1-camps, a genetically encoded cAMP FRET sensor, for use in the living brain. We find that a subset of the PDF-expressing neurons respond to PDF with long-lasting cAMP increases and confirm that such responses require the PDF receptor. In contrast, an unrelated Drosophila neuropeptide, DH31, stimulates large cAMP increases in all PDF-expressing clock neurons. Thus, the network of ∼150 clock neurons displays widespread, though not uniform, PDF receptivity. This work introduces a sensitive means of measuring cAMP changes in a living brain with subcellular resolution. Specifically, it experimentally confirms the longstanding hypothesis that PDF is a direct modulator of most neurons in the Drosophila clock network

The Lipophorin Receptor of Drosophila melanogaster

Animals carry lipids such as hydrocarbons, fats, and sterols throughout their circulatory systems bound to a carrier protein known as lipophorin. The lipophorin receptor has been characterized in locusts, mosquitoes and cockroaches yet little is known about it in Drosophila melanogaster. An antibody against the eleven variants of the lipophorin receptor was developed and tested. Although this was the main feature of the work, several preliminary experiments using RNA interference were conducted to determine the effects of lipophorin receptor. Flies whose lipophorin receptor proteins were knocked down were found to have no major differences in locomotor activity in total darkness suggesting that their circadian rhythms are unaffected. The same flies were found to have extensive differences in their cuticular hydrocarbon profiles as compared with wild‐type flies. Whole‐mount tissue staining of Drosophila adult brains revealed that several cells in the central nervous system are immunoreactive with the anti‐Lipophorin receptor antibody.MAS

Junior Rounds: an educational initiative to improve role transitions for junior residents

Abstract Objective At our institution, Morning Report focuses mostly on diagnostic reasoning. This makes it a challenge for first-year residents to learn to manage common on-call emergencies, such as hyperkalemia. We sought to improve their preparedness for the transitions they would encounter: from medical student to physician at the beginning of the academic year, and from junior resident to senior resident toward the end. In response to feedback, we developed the Junior Rounds curriculum: a weekly session focused on the approach to commonly encountered on-call emergencies and internal medicine referrals. Anonymous surveys were sent to trainees, and iterative analysis of monthly feedback led to changes to Junior Rounds. Results Junior Rounds was implemented from August 2015 to June 2016. Thirty-nine of 92 possible respondents (44%) completed surveys in that period. Most respondents agreed that Junior Rounds met their educational needs, was presented at an appropriate level, and was more important to their learning than other available educational activities. Our experience demonstrates that dedicated time for level-specific learning aimed to support the transitions of junior residents can be successfully achieved. Iterative adjustment to these rounds based on feedback allowed for evolution of the curriculum to meet the changing priorities of junior learners

MOESM1 of Junior Rounds: an educational initiative to improve role transitions for junior residents

Additional file 1: Appendix S1. Junior Rounds 2015–2016 survey questions