A case of febrile ulceronecrotic Mucha-Habermann disease responsive to systemic corticosteroids.

Febrile ulceronecrotic Mucha-Habermann disease (FUMHD) is a rare, potentially fatal subtype of pityriasis lichenoides et varioliformis acuta (PLEVA). Herein, we present a rare case of a 14-year-old male without significant past medical history who was diagnosed with FUMHD without a clear inciting factor. He was effectively treated with systemic corticosteroids with complete resolution of symptoms.

Unwitting adult marijuana poisoning: a case series.

STUDY PURPOSE: With increasing state legalization, marijuana use has become commonplace throughout much of the United States. Existing literature on unintentional exposure focuses primarily on children.We report on a cluster of adults with unwitting marijuana exposure. METHODS: A cluster of cases were referred to the Medical Toxicology Service after ingesting marijuana-contaminated food at a family event. We conducted a retrospective analysis of twelve subject charts and a qualitative analysis with six of these subjects who willingly consented to be interviewed about their experiences. The study was approved by the Institutional Review Board. RESULTS: Three of the subjects (25%) required prolonged observation due to persistent symptoms. Eleven (92%) were urine immunoassay positive for tetrahydrocannabinol (THC). Two subjects (17%) tested positive for ethanol in their blood. Common symptoms experienced by the subjects included confusion (50%), difficulty speaking (67%), nausea (25%), tremors (17%), and feelings of unreality (33%). All interviewed subjects reported sleepiness and three (50%) reported a negative impact on work. Subjects also reported multiple emotions, including anger, confusion, disbelief, and helplessness. None of the cases resulted in admission for critical care or death. CONCLUSIONS: Our series illuminates effects of unwitting and/or unintentional marijuana exposure in adults. Unintentional marijuana poisonings have increased, but legal and regulatory barriers have limited the study of marijuana outside highly controlled conditions. While the marijuana exposure in this study did not result in admission for critical care or death, it did result in psychological distress and adversely affected work in some cases.

Rapid, efficient, and economical synthesis of PET tracers in a droplet microreactor: application to O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET).

BACKGROUND: Conventional scale production of small batches of PET tracers (e.g. for preclinical imaging) is an inefficient use of resources. Using O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET), we demonstrate that simple microvolume radiosynthesis techniques can improve the efficiency of production by consuming tiny amounts of precursor, and maintaining high molar activity of the tracers even with low starting activity. PROCEDURES: The synthesis was carried out in microvolume droplets manipulated on a disposable patterned silicon "chip" affixed to a heater. A droplet of [18F]fluoride containing TBAHCO3 was first deposited onto a chip and dried at 100 °C. Subsequently, a droplet containing 60 nmol of precursor was added to the chip and the fluorination reaction was performed at 90 °C for 5 min. Removal of protecting groups was accomplished with a droplet of HCl heated at 90 °C for 3 min. Finally, the crude product was collected in a methanol-water mixture, purified via analytical-scale radio-HPLC and formulated in saline. As a demonstration, using [18F]FET produced on the chip, we prepared aliquots with different molar activities to explore the impact on preclinical PET imaging of tumor-bearing mice. RESULTS: The microdroplet synthesis exhibited an overall decay-corrected radiochemical yield of 55 ± 7% (n = 4) after purification and formulation. When automated, the synthesis could be completed in 35 min. Starting with < 370 MBq of activity, ~ 150 MBq of [18F]FET could be produced, sufficient for multiple in vivo experiments, with high molar activities (48-119 GBq/µmol). The demonstration imaging study revealed the uptake of [18F]FET in subcutaneous tumors, but no significant differences in tumor uptake as a result of molar activity differences (ranging 0.37-48 GBq/µmol) were observed. CONCLUSIONS: A microdroplet synthesis of [18F]FET was developed demonstrating low reagent consumption, high yield, and high molar activity. The approach can be expanded to tracers other than [18F]FET, and adapted to produce higher quantities of the tracer sufficient for clinical PET imaging.

Dynamic mechanical response of elastic spherical inclusions to impulsive acoustic radiation force excitation.

Acoustic radiation force impulse imaging has been used clinically to study the dynamic response of lesions relative to their background material to focused, impulsive acoustic radiation force excitations through the generation of dynamic displacement field images. Dynamic displacement data are typically displayed as a set of parametric images, including displacement immediately after excitation, maximum displacement, time to peak displacement, and recovery time from peak displacement. To date, however, no definitive trends have been established between these parametric images and the tissues' mechanical properties. This work demonstrates that displacement magnitude, time to peak displacement, and recovery time are all inversely related to the Young's modulus in homogeneous elastic media. Experimentally, pulse repetition frequency during displacement tracking limits stiffness resolution using the time to peak displacement parameter. The excitation pulse duration also impacts the time to peak parameter, with longer pulses reducing the inertial effects present during impulsive excitations. Material density affects tissue dynamics, but is not expected to play a significant role in biological tissues. The presence of an elastic spherical inclusion in the imaged medium significantly alters the tissue dynamics in response to impulsive, focused acoustic radiation force excitations. Times to peak displacement for excitations within and outside an elastic inclusion are still indicative of local material stiffness; however, recovery times are altered due to the reflection and transmission of shear waves at the inclusion boundaries. These shear wave interactions cause stiffer inclusions to appear to be displaced longer than the more compliant background material. The magnitude of shear waves reflected at elastic lesion boundaries is dependent on the stiffness contrast between the inclusion and the background material, and the stiffness and size of the inclusion dictate when shear wave reflections within the lesion will interfere with one another. Jitter and bias associated with the ultrasonic displacement tracking also impact the estimation of a tissue's dynamic response to acoustic radiation force excitation.