Success Rates for Reduction of Pediatric Distal Radius and Ulna Fractures by Emergency Physicians.

BACKGROUND: Emergency physicians are trained in urgent fracture reduction. Many hospitals lack readily available in-house orthopedic coverage. OBJECTIVES: The aim of this study was to determine success rates for reduction of pediatric distal radius or ulna fractures by emergency department (ED) physicians. METHODS: We conducted a retrospective study of children younger than 18 years presenting to a large, urban, freestanding children's hospital from January 1, 2009, to December 31, 2010, with forearm fracture. Exclusions included open fracture, those requiring immediate surgical intervention, or additional fractures. The primary end point was the proportion of successful closed forearm fracture reductions in the ED, as defined by orthopedic follow-up. RESULTS: All reductions were performed by a board-certified/eligible pediatric emergency medicine (PEM) physician or PEM fellow. Two hundred ninety-five fractures were reduced in the ED during the study period. Mean age was 8.27 years (median, 8 years; range, 1-16 years), and males comprised 69.2% (n = 204). A total of 222 fractures (76%) were of the distal forearm, and 70 involved the midshaft (24%). Orthopedic follow-up was completed in 77.3%. A total of 33 patients (11%) required remanipulation; 24 in the distal forearm fracture group (22 closed reductions, 2 open reductions with internal fixation) versus 9 in the midshaft group (7 closed reductions, 2 open reductions with internal fixation) (P = 0.948). CONCLUSIONS: The literature reveals 7% to 39% of children with fracture reductions performed in the ED by orthopedic surgeons/residents require remanipulation. Our rate of 11% is consistent within that range. With training, PEM physicians have similar success rates as orthopedists in forearm fracture reductions.

Intoxication from the novel synthetic cannabinoids AB-PINACA and ADB-PINACA: A case series and review of the literature.

Synthetic cannabinoids (SC), are a novel class of designer drugs which emerged as a drug of abuse in the late 2000's. We report a case series of 6 patients who may have smoked a synthetic cannabinoid product in a remote wilderness setting. They presented with varying degrees of altered mental status, agitation, and seizures. Two were confirmed to have AB-PINACA, ADB-PINACA and their respective pentanoic acid metabolites in biological specimens via liquid chromatography time-of-flight mass spectrometry (LC-TOF/MS). Both compounds had DEA Schedule I classification at the time of case presentation, and 22 SCs are currently temporary or permanent DEA Schedule I. More than 150 SCs are known to date, and new compounds are appearing at a rapid rate on darknet and surface web e-commerce websites, marketed as "research chemicals" or "legal highs." The scale and rapidity of SC evolution make legal control and analytical detection difficult. Nontargeted testing with liquid chromatography high resolution mass spectrometry (LC-HRMS), examining both parent compounds and metabolites, is the ideal method for novel SC identification and confirmation. Due to full agonism at the cannabinoid receptors CB1 and CB2, clinical effects are more severe than marijuana, which is a partial cannabinoid receptor agonist. They include agitated delirium, lethargy and coma, seizures, tachycardia, hypertension, and hallucinations, among other findings. Treatment is primarily symptomatic and aimed at airway protection and control of agitation and seizures. SCs do not appear to be abating anytime soon and require the cooperation of law enforcement, analytical scientists, and clinicians to adequately control. This article is part of the Special Issue entitled 'Designer Drugs and Legal Highs.'

Bridging length scales to measure polymer assembly.

Time-resolvable quantitative measurements of polymer concentration are very useful to elucidate protein polymerization pathways. There are numerous techniques to measure polymer concentrations in purified protein solutions, but few are applicable in vivo. Here we develop a methodology combining microscopy and spectroscopy to overcome the limitations of both approaches for measuring polymer concentration in cells and cell extracts. This technique is based on quantifying the relationship between microscopy and spectroscopy measurements at many locations. We apply this methodology to measure microtubule assembly in tissue culture cells and Xenopus egg extracts using two-photon microscopy with FLIM measurements of FRET. We find that the relationship between FRET and two-photon intensity quantitatively agrees with predictions. Furthermore, FRET and intensity measurements change as expected with changes in acquisition time, labeling ratios, and polymer concentration. Taken together, these results demonstrate that this approach can quantitatively measure microtubule assembly in complex environments. This methodology should be broadly useful for studying microtubule nucleation and assembly pathways of other polymers.

Developing and Testing a Bayesian Analysis of Fluorescence Lifetime Measurements.

FRET measurements can provide dynamic spatial information on length scales smaller than the diffraction limit of light. Several methods exist to measure FRET between fluorophores, including Fluorescence Lifetime Imaging Microscopy (FLIM), which relies on the reduction of fluorescence lifetime when a fluorophore is undergoing FRET. FLIM measurements take the form of histograms of photon arrival times, containing contributions from a mixed population of fluorophores both undergoing and not undergoing FRET, with the measured distribution being a mixture of exponentials of different lifetimes. Here, we present an analysis method based on Bayesian inference that rigorously takes into account several experimental complications. We test the precision and accuracy of our analysis on controlled experimental data and verify that we can faithfully extract model parameters, both in the low-photon and low-fraction regimes.

Design of phase-shifted hybrid silicon distributed feedback lasers.

We present data on the design and performance analysis of phase shifted distributed feedback (DFB) lasers on the hybrid silicon platform. The lasing wavelength for various input currents and temperatures, for devices with standard quarter-wavelength, 60 µm and 120 µm-long phase shift are compared for mode stability and output power. The pros and cons of including a large phase shift region in the grating design are analyzed.