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Effective activation of macrophages through phagocytic Fcγ receptors (FcγR) has been shown to require selenoprotein K (Selk). We set out to determine whether the FcγR-mediated uptake process itself also requires Selk and potential underlying mechanisms. Macrophages from Selk knockout (KO) mice were less efficient compared with wild-type (WT) controls in engulfing IgG-coated fluorescent beads. Using LC-MS/MS to screen for Selk-binding partners involved in FcγR-mediated phagocytosis, we identified Arf-GAP with SH3 domain, ANK repeat, and PH domain-containing protein 2 (ASAP2). Coimmunoprecipitation assays confirmed interactions between Selk and ASAP2. Selk was required for ASAP2 to be cleaved by calpain-2 within the Bin/Amphiphysin/Rvs (BAR) domain of ASAP2. BAR domains promote membrane association, which was consistent with our data showing that Selk deficiency led to retention of ASAP2 within the phagocytic cup. Because Selk was recently identified as a cofactor for the palmitoylation of certain proteins, we investigated whether ASAP2 was palmitoylated and whether this was related to its cleavage by calpain-2. Acyl/biotin exchange assays and MALDI-TOF analysis showed that cysteine-86 in ASAP2 was palmitoylated in WT, but to a much lesser extent in KO, mouse macrophages. Inhibitors of either palmitoylation or calpain-2 cleavage and rescue experiments with different versions of Selk demonstrated that Selk-dependent palmitoylation of ASAP2 leads to cleavage by calpain-2 within the BAR domain, which releases this protein from the maturing phagocytic cup. Overall, these findings identify ASAP2 as a new target of Selk-dependent palmitoylation and reveal a new mechanism regulating the efficiency of FcγR-mediated phagocytosis.

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BACKGROUND: Patient satisfaction is one measure of the quality of emergency department (ED) care. The impact of survey delivery method on patient satisfaction in the ED remains unknown. OBJECTIVE: We hypothesized that self-administered surveys in the ED would yield a higher response rate and different satisfaction compared to mailed surveys. METHODS: This observational study was conducted during a 2-month period in an urban, tertiary-care, university-based ED. Eligible patients were randomized to either complete an on-site satisfaction survey in the ED at discharge or to complete an identical survey mailed 1 week after discharge. The primary outcome was the reported overall satisfaction of on-site vs. mail-out surveys. Satisfaction was measured using Likert-type scales and dichotomized outcomes were compared using a χ(2) test and logistic regression. RESULTS: Two hundred and forty-two of 457 eligible patients randomized to the on-site group and 275 of 1152 patients in the mail-out group completed a survey (53% vs. 24%; p < 0.001). Compared with the mail-out group, on-site subjects reported higher overall satisfaction (79.6% vs. 68.9%; p = 0.006), significantly higher satisfaction with their nurses' (p < 0.001) and doctors' listening skills (p < 0.001), and were more likely to recommend this ED to friends or family (71.4%, vs. 56.6%; p = 0.001). CONCLUSIONS: We found that patients who completed satisfaction surveys in the ED reported higher satisfaction than those who received mailed surveys. In addition, measuring patient satisfaction by self-administered on-site surveys at the time of discharge from the ED yields a significantly higher response rate than measuring satisfaction using mailed surveys.

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Selk is an ER transmembrane protein important for calcium flux and macrophage activation, but its role in foam cell formation and atherosclerosis has not been evaluated. BMDMs from Selk(-/-) mice exhibited decreased uptake of modLDL and foam cell formation compared with WT controls, and the differences were eliminated with anti-CD36 blocking antibody. CD36 expression was decreased in TNF-α-stimulated Selk(-/-) BMDMs compared with WT controls. Fluorescence microscopy revealed TNF-α-induced clustering of CD36 in WT BMDMs indicative of lipid raft localization, which was absent in Selk(-/-) BMDMs. Fractionation revealed lower levels of CD36 reaching lipid rafts in TNF-α-stimulated Selk(-/-) BMDMs. Immunoprecipitation showed that Selk(-/-) BMDMs have decreased CD36 palmitoylation, which occurs at the ER membrane and is crucial for stabilizing CD36 expression and directing its localization to lipid rafts. To assess if this phenomenon had a role in atherogenesis, a HFD was fed to irradiated Ldlr(-/-) mice reconstituted with BM from Selk(-/-) or WT mice. Selk was detected in aortic plaques of controls, particularly in macrophages. Selk(-/-) in immune cells led to reduction in atherosclerotic lesion formation without affecting leukocyte migration into the arterial wall. These findings suggest that Selk is important for stable, localized expression of CD36 in macrophages during inflammation, thereby contributing to foam cell formation and atherogenesis.

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INTRODUCTION: Patient satisfaction is an important measure of emergency department (ED) quality of care. Little is known about providers' ability to estimate patient satisfaction. We aimed to measure providers' ability to assess patient satisfaction and hypothesized that providers could accurately estimate overall patient satisfaction. METHODS: We surveyed ED patients regarding satisfaction with their care. Treating providers completed analogous surveys, estimating patients' responses. Sexual assault victims and non-English-speaking or severely ill patients were excluded. Satisfaction responses were categorized as "satisfied" or "not satisfied." Patient satisfaction scores were considered the "gold standard," and providers' perceptions of the patient satisfaction were considered tests. Measures of diagnostic accuracy, such as positive predictive value (PPV) and sensitivity, were used to assess how accurately the provider could estimate his or her patient's satisfaction. RESULTS: Here, 242/457 eligible patients (53%) completed the survey; 227 providers (94%) completed a corresponding survey. Subject-reported overall satisfaction was 96.6%, compared with a provider-estimated rate of 94.4%. The sensitivity and PPV of the provider's estimate of the patient's satisfaction were 95.2 (95% confidence interval [CI] 91.4, 97.7) and 97.5 (95% CI 94.4, 99.2), respectively, for overall patient satisfaction. The PPV was similar for clarity of communication. The PPV was 78.9 for perceived length of ED stay (99% CI 70.8, 85.6) and 82.6 for quality of pain control (95% CI 68.6, 92.3). Accuracy of attending and resident estimates of patient satisfaction did not differ significantly. The agreement between patient-reported and provider-estimated patient satisfaction was not associated with age, gender, patient disposition, or ED divert status. CONCLUSION: Providers are able to assess overall patient satisfaction and clarity of communication with a high accuracy. Physician estimates of pain control and perceived length of stay have a moderate accuracy.

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Se is a potent nutritional antioxidant important for various aspects of human health. Because asthma has been demonstrated to involve increased oxidative stress, levels of Se intake have been hypothesized to play an important role in the pathogenesis of asthma. However, significant associations between Se status and prevalence or severity of asthma have not been consistently demonstrated in human studies. This highlights both the complex etiology of human asthma and the inherent problems with correlative nutritional studies. In this review, the different findings in human studies are discussed along with results from limited intervention studies. Mouse models of asthma have provided more definitive results suggesting that the benefits of Se supplementation may depend on an individual's initial Se status. This likely involves T helper cell differentiation and the mechanistic studies that have provided important insight into the effects of Se levels on immune cell function are summarized. Importantly, the benefits and adverse effects of Se supplementation must both be considered in using this nutritional supplement for treating asthma. With this in mind new approaches are discussed that may provide more safe and effective means for using Se supplementation for asthma or other disorders involving inflammation or immunity.

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Calpains are proteolytic enzymes that modulate cellular function through cleavage of targets, thereby modifying their actions. An important role is emerging for calpains in regulating inflammation and immune responses, although specific mechanisms by which this occurs have not been clearly defined. In this study, we identify a novel target of calpain, selenoprotein K (SelK), which is an endoplasmic reticulum transmembrane protein important for Ca(2+) flux in immune cells. Calpain-mediated cleavage of SelK was detected in myeloid cells (macrophages, neutrophils, and dendritic cells) but not in lymphoid cells (B and T cells). Both m- and µ-calpain were capable of cleaving immunoprecipitated SelK, but m-calpain was the predominant isoform expressed in mouse immune cells. Consistent with these results, specific inhibitors were used to show that only m-calpain cleaved SelK in macrophages. The cleavage site in SelK was identified between Arg(81) and Gly(82) and the resulting truncated SelK was shown to lack selenocysteine, the amino acid that defines selenoproteins. Resting macrophages predominantly expressed cleaved SelK and, when activated through different Toll-like receptors (TLRs), SelK cleavage was inhibited. We found that decreased calpain cleavage was due to TLR-induced up-regulation of the endogenous inhibitor, calpastatin. TLR-induced calpastatin expression not only inhibited SelK cleavage, but cleavage of another calpain target, talin. Moreover, the expression of the calpain isoforms and calpastatin in macrophages were different from T and B cells. Overall, our findings identify SelK as a novel calpain target and reveal dynamic changes in the calpain/calpastatin system during TLR-induced activation of macrophages.

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BACKGROUND: Methamphetamine is an illicit stimulant that is typically smoked, insufflated, or injected. We report an unusual method of ingesting methamphetamine called "parachuting" and its implications for the treatment of "body stuffers." CASE REPORT: A 25-year-old man wrapped methamphetamine into a plastic baggie and ingested it in an attempt to "parachute." He presented to an Emergency Department 10 hours after his ingestion because he realized that he forgot to puncture the baggie. He had no complaints and had a transient tachycardia. He was treated with activated charcoal and whole bowel irrigation, observed for 24 hours, and discharged. He returned 42 hours after his ingestion with tachycardia (220 bpm), agitation, hypertension (179/74 mmHg), and rhabdomyolysis (CPK 7771 U/L), requiring mechanical ventilation and a midazolam drip (10 mg/hr). CONCLUSION: "Parachuting" is a novel method of ingesting methamphetamine. We report a case of a single-packet "body stuffer" with severe symptom onset that was delayed over 36 hours. Treatment protocols for "body stuffers" using this technique may require more prolonged observation and/or imaging studies to determine the absence of gastrointestinal packets.

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