Faculty Bibliography

The diagnosis of deep venous thrombosis (DVT) in patients presenting to the emergency department (ED) has traditionally been limited to examinations by radiologists and ultrasound technicians. Although contrast venography is considered the criterion standard for diagnosis of DVT, time, personnel, cost, exposure to radiation, and the invasive nature of the study (need for venous access) potentially limit the ability to perform the study in an emergent setting. Ultrasonography is an alternative method for thrombus detection and is widely preferred. However, in many health care settings, consultative ultrasound services may not be available immediately, especially after hours and on weekends. Based on recent studies demonstrating accuracy in adult patients, emergency sonographic evaluation of DVT by emergency physicians is considered a core emergency ultrasound application and is recently recommended as standard training to all emergency medicine residents. The diagnosis of DVT in children by emergency ultrasound in the pediatric ED has not been previously described. We present 3 cases of DVT in adolescents identified by emergency ultrasound evaluation in the pediatric ED.

OBJECTIVE: To evaluate inhalation device cleaning practices of children with asthma and its effect on their asthma morbidity. METHODS: A survey of patients aged 4 to 18 years admitted to an urban pediatric emergency department (ED) with an acute asthma exacerbation. Questions included demographics, asthma history, preference of delivery devices, and frequency of device cleaning. Patients were followed until their disposition from the ED, or until the end of their hospitalization, if admitted. RESULTS: 220 subjects completed the survey. Mean age was 9.2 (+/- 3.9) years-old. One hundred and four (47.3%) patients used both nebulizers and spacer devices, while 18 (8.1%) used spacers only and 98 (44.5%) used nebulizers alone. Seventy-seven (38.1%; 95%CI: 31.7%-45.0%) patients cleaned their nebulizers and 57 (46.7%; 95%CI: 38.1%-55.4%) cleaned their spacer devices after each use as recommended by the Centers for Disease Control. There were no detectable differences in visit admission rate, total number of previous admissions, number of asthma exacerbations per year, and number of ED visits in one year between users who cleaned their devices after every, or every other use, compared to those who cleaned their devices less frequently. CONCLUSION: Although the majority of patients did not follow accepted guidelines for inhalation device cleaning, further studies are necessary to correlate cleaning practices to patients' clinical outcome

Foreign body ingestion is a common occurrence in children. Morbidity associated with ingestion is rare and is dependent on the type of foreign body ingested. We report a case of a 9-year-old boy who developed intestinal obstruction and perforation following ingestion of magnetic-backed earrings

The goals of this study were to develop compounds that were selective and highly efficacious agonists at alpha-7 receptors, while varying in antagonist activity; and to test the hypothesis that these compounds had memory-related and neuroprotective actions associated with both agonist and antagonist alpha-7 receptor activities. Three compounds were identified; E,E-3-(cinnamylidene)anabaseine (3-CA), E,E-3-(2-methoxycinnamylidene) anabaseine (2-MeOCA) and E,E-3-(4-methoxycinnamylidene) anabaseine (4-MeOCA) each displaced [125I]alpha-bungarotoxin binding from rat brain membranes and activated rat alpha-7 receptors in a Xenopus oocyte expression system fully efficaciously. The potency series for binding and receptor activation was 2-MeOCA > 4-MeOCA = 3-CA and 2-MeOCA = 3-CA > 4-MeOCA, respectively. No compound significantly activated oocyte-expressed alpha-4beta-2 receptors. Although each cinnamylidene-anabaseine caused a long-term inhibition of alpha-7 receptors, as measured by ACh-application 5 min later, this inhibition ranged considerably, from less than 20% (3-CA) to 90% (2-MeOCA) at an identical concentration (10 microM). These compounds improved passive avoidance behavior in nucleus basalis lesioned rats, with 2-MeOCA most potent in this respect. In contrast, only 3-CA was neuroprotective against neurite loss during nerve growth factor deprivation in differentiated rat pheochromocytoma (PC12) cells. Choline, an efficacious alpha-7 agonist without antagonist activity, was also protective in this model. These results suggest that the neurite-protective action of alpha-7 receptor agonists may be more sensitive to potential long-term antagonist properties than acute behavioral actions are.

The alpha7 nicotinic receptor agonist 3-[2,4-dimethoxybenzylidene]anabaseine (DMXB; GTS-21) was investigated for its ability to: (1) activate a variety of nicotinic receptor subtypes in Xenopus oocytes; (2) improve passive avoidance and spatial Morris water task performances in mecamylamine-sensitive manners in bilaterally nucleus basalis lesioned rats; and (3) elevate high-affinity [3H]acetylcholine (ACh) and high-affinity alpha-[125I]bungarotoxin binding in rat neocortex following 2 weeks of daily injections. DMXB (100 microM) activated alpha7 homo-oligomeric receptors, without significant activity at alpha2-, alpha3- and alpha4-containing subtypes. Mecamylamine blocked rat alpha7 receptors weakly if co-administered with agonist, but much more potently when pre-applied. Bilateral ibotenic acid lesions of the nucleus basalis interfered with passive avoidance and spatial memory-related behaviors. DMXB (0.5 mg/kg, i.p.) improved passive avoidance behavior in lesioned animals in a mecamylamine-sensitive manner. DMXB (0.5 mg/kg 15 min before each session) also improved performance in the training and probe components of the Morris water task. DMXB-induced improvement in the probe component but not the training phase was mecamylamine-sensitive. [3H]ACh binding was elevated after 14 days of daily i.p. injections with 0.2 mg/kg nicotine but not after 1 mg/kg DMXB. Neither drug elevated high-affinity alpha-[125I]bungarorotoxin binding over this interval.