Fatty acid ratio analysis identifies changes in competent meroplanktonic larvae sampled over different supply events.

Planktonic communities are a cornerstone of ocean food webs. Early benthic performance of meroplanktonic organisms is shaped by their life stages in planktonic communities. Fatty acid profiles of marine invertebrates are a good indicator of their nutritional state and allow inferring how dietary regimes experienced during larval pelagic life may drive their pre- and post-metamorphosis performance. Fatty acid profiles of Carcinus maenas megalopae were analysed during four larval supply events in two consecutive years to better understand the variability in their nutritional state at settlement. The logratio analysis of fatty acids showed differences between the four larval supply events, with five ratios explaining 83.1% of the variance. The ratios that contributed to separate larval supply events presented a combination of essential, de novo synthetized and diet origin fatty acids (e.g., phytanate/20:4 n-6, 16:0/18:2 n-4). The high fatty acid signature dispersion found within the same supply event suggests that larvae settling at Ria de Aveiro (Portugal) developed through different planktonic feeding zones and experienced contrasting feeding regimes. The fatty acid profile of megalopae demonstrated a high contribution of diatoms, flagellates and bacteria in the larval diet of C. maenas. The present study demonstrated differences between supply events, although a high variability of larval phenotypes was recorded within the same supply event.

Use of single-dose activated charcoal among Canadian pediatric emergency physicians.

OBJECTIVE: Gastric decontamination with single-dose activated charcoal (SDAC) is a mainstay in emergency department (ED) treatment of ingestions. Guidelines updated in 2005 encourage practitioners to use SDAC only in toxic ingestions presenting within 1 hour. Despite these guidelines, adult studies demonstrate a significant lack of consensus. This study examined the proposed use of SDAC for gastric decontamination in common pediatric ingestion scenarios by emergency physicians working in Canadian pediatric EDs. METHODS: A standardized survey consisting of 5 clinical scenarios was mailed to all physicians with a primary clinical appointment to the ED at 9 Canadian children's hospitals. RESULTS: One hundred thirty-one physicians were surveyed, and 95 (72%) responded. The majority of respondents were pediatricians (68.1%) with a mean of 15.0 years of experience (SD, 6.8 years). Of those surveyed; 91 (97.8%) would use SDAC for a toxic ingestion presenting in less than 1 hour; 35 (36.8%) would use SDAC for a toxic ingestion presenting after 3 hours; 61 (64.9%) would use SDAC for a nontoxic exploratory ingestion presenting in less than 1 hour; and 29 (30.5%) would use SDAC for a mildly symptomatic intentional ingestion presenting at an unknown time. Eleven (11.7%) would use SDAC for an ingestion of a substance that does not adsorb to SDAC. CONCLUSIONS: There is variation in the use of SDAC among emergency physicians working in Canadian pediatric EDs. This variation suggests that optimal management is not clear and that continued education and research are required.

A randomized controlled trial of mist in the acute treatment of moderate croup.

OBJECTIVE: To determine whether the use of mist improves clinical symptoms in children presenting to the emergency department (ED) with moderate croup. METHODS: Children 3 months to 6 years of age were eligible for the study if they presented to the ED with moderate croup. Moderate croup was defined as a croup score of 2-7. The patients were randomly assigned to receive either mist (humidified oxygen) via mist stick or no mist. The patients had croup scores measured at baseline and every 30 minutes for up to two hours. At these intervals the following parameters were also measured: heart rate, respiratory rate, oxygen saturation, and patient comfort score. The patients were treated until the croup score was less than 2 or until two hours had elapsed. All patients initially received a dose of oral dexamethasone (0.6 mg/kg). Other treatments, such as racemic epinephrine or inhaled budesonide, were given at the discretion of the treating physician. The research assistants were unaware of the assigned treatments. RESULTS: There were 71 patients enrolled in the study; 35 received mist and 36 received no mist. The two treatment groups had similar characteristics at baseline. The median baseline croup score was 4 in both groups. The outcomes were measured as the change from baseline at 30, 60, 90, and 120 minutes. The change in the croup score from baseline in the mist group was not statistically different from the croup score change in the group that did not receive mist (p = 0.39). There was also no significant difference in improvement of oxygen saturation, heart rate, or respiratory rate at any of the assessment times. There was no adverse effect from the mist therapy. CONCLUSIONS: Mist therapy is not effective in improving clinical symptoms in children presenting to the ED with moderate croup.