Acoustic droplet ejection (ADE) is a powerful technology that supports crystallographic applications such as growing, improving and manipulating protein crystals. A fragment‐screening strategy is ...described that uses ADE to co‐crystallize proteins with fragment libraries directly on MiTeGen MicroMeshes. Co‐crystallization trials can be prepared rapidly and economically. The high speed of specimen preparation and the low consumption of fragment and protein allow the use of individual rather than pooled fragments. The Echo 550 liquid‐handling instrument (Labcyte Inc., Sunnyvale, California, USA) generates droplets with accurate trajectories, which allows multiple co‐crystallization experiments to be discretely positioned on a single data‐collection micromesh. This accuracy also allows all components to be transferred through small apertures. Consequently, the crystallization tray is in equilibrium with the reservoir before, during and after the transfer of protein, precipitant and fragment to the micromesh on which crystallization will occur. This strict control of the specimen environment means that the crystallography experiments remain identical as the working volumes are decreased from the few microlitres level to the few nanolitres level. Using this system, lysozyme, thermolysin, trypsin and stachydrine demethylase crystals were co‐crystallized with a small 33‐compound mini‐library to search for fragment hits. This technology pushes towards a much faster, more automated and more flexible strategy for structure‐based drug discovery using as little as 2.5 nl of each major component.
A method is presented for screening fragment libraries using acoustic droplet ejection to co-crystallize proteins and chemicals directly on micromeshes with as little as 2.5 nl of each component. ...This method was used to identify previously unreported fragments that bind to lysozyme, thermolysin, and trypsin. Acoustic droplet ejection (ADE) is a powerful technology that supports crystallographic applications such as growing, improving and manipulating protein crystals. A fragment-screening strategy is described that uses ADE to co-crystallize proteins with fragment libraries directly on MiTeGen MicroMeshes. Co-crystallization trials can be prepared rapidly and economically. The high speed of specimen preparation and the low consumption of fragment and protein allow the use of individual rather than pooled fragments. The Echo 550 liquid-handling instrument (Labcyte Inc., Sunnyvale, California, USA) generates droplets with accurate trajectories, which allows multiple co-crystallization experiments to be discretely positioned on a single data-collection micromesh. This accuracy also allows all components to be transferred through small apertures. Consequently, the crystallization tray is in equilibrium with the reservoir before, during and after the transfer of protein, precipitant and fragment to the micromesh on which crystallization will occur. This strict control of the specimen environment means that the crystallography experiments remain identical as the working volumes are decreased from the few microlitres level to the few nanolitres level. Using this system, lysozyme, thermolysin, trypsin and stachydrine demethylase crystals were co-crystallized with a small 33-compound mini-library to search for fragment hits. This technology pushes towards a much faster, more automated and more flexible strategy for structure-based drug discovery using as little as 2.5 nl of each major component.
Objectives
Emergency department (ED) crowding is detrimental to patients and staff. During traditional triage, nurses evaluate patients and identify their level of emergency. During team triage, ...physicians and/or nurse practitioners (NPs) and physician assistants (PAs) place orders, laboratory results, intravenous lines (IVs), and imaging in triage. Team triage improves access to testing and decreases length of stay. However, ordering practices in team triage may lead to overtesting.
Methods
This is a retrospective review of patients seen before and after a team triage process was established. Percentage of patients receiving testing and the diagnostic yields of troponins, lactates, international normalized ratios (INRs), blood cultures, glomerular filtration rates (GFR), and head computed tomography (CT) images were studied.
Results
A total of 704 traditionally triaged patients and 862 team triaged patients met inclusion criteria. Comparing traditional versus team triaged patients, the proportion of patients discharged was 0.44 versus 0.53 (P < 0.001), and the length of stay to discharge was 417 versus 375 minutes (P = 0.003). Comparing traditional versus team triage, a head CT was obtained 12.5% versus 5.7% (P < 0.001) of the time with diagnostic yield 45.5% versus 52% (not significant), troponin was obtained 51.3% versus 45.9% (not significant) of the time with diagnostic yield 14.9% versus 13.9% (not significant), lactate was obtained 41.6% versus 32.1% (P = 0.011) of the time with diagnostic yield 18.4% versus 12.3% (not significant), INR was obtained 70.2% versus 55.8% (P = 0.007) of the time with diagnostic yield 15.8% versus 10.5% (P = 0. 042), GFR was obtained 99.3% versus 98.4% (not significant) of the time with diagnostic yield 18.9% versus 13.7% (P = 0.02), and blood cultures were obtained 23.4% versus 7.3% (P < 0.001) of the time with diagnostic yield 7.3% versus 9.3% (not significant).
Conclusion
Compared with traditional triage, the team triage process increased discharges and decreased time to discharge, but did not lead to increased testing or decreased diagnostic yield.
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