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Executive control development typically has been conceptualized to result from quantitative changes in the efficiency of the underlying processes. In contrast, the present study addressed the possibility of qualitative change with age by examining how children and adults detect task switches. Participants in three age groups (5- and 10-year-old children, young adults) completed two conditions of a cued task-switching paradigm where task cues were presented either in isolation or in conjunction with transition cues. Five-year-olds performed better with transition cues, whereas the reverse effect was observed at age 10 and with adults. Unlike 5-year-olds who detect switches after semantically processing cues, older participants strategically detect switches based on perceptual processing only. Age-related qualitative changes promote increasingly optimal adjustment of executive resources with age., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Purpose: The mortality of an unrepaired abdominal aortic aneurysm (AAA) generally exceeds the mortality associated with surgical repair. However, as our longevity increases, more frequently we see patients whose risk of surgical repair approximates the risk of rupture. We present an extra-anatomic bypass graft with complete aneurysm exclusion by iliac ligation and coil embolization of the aneurysm as an alternative for these high-risk patients., Methods: An extra-anatomic bypass graft, followed by bilateral iliac artery ligation (retroperitoneal approach) and complete coil embolization of the AAA, was performed in eight patients (mean age, 77 years) found to be at prohibitive operative risk because of multiple comorbidities (American Society of Anesthesiologists class IV). Most patients (5 of 8) were symptomatic on presentation with a mean AAA diameter of 7 cm (range, 6.7-9.5 cm). We repair approximately 30 infrarenal aneurysms per year electively at our institution., Results: All patients tolerated the surgical procedures. The average hospital stay was 8 days. All but two aneurysms demonstrated complete thrombosis by 48 hours. After 48 months there was no incidence of graft thrombosis, peripheral ischemia, visceral ischemia or thrombus infection. There was one perioperative death from aspiration pneumonia. Seventy-five percent (6 of 8) of patients have survived at least 1 year without surgical complications. No patient has had a ruptured aneurysm., Conclusion: Combining an extra-anatomic bypass graft and complete exclusion of the AAA by ligation of the common iliac arteries and a coil embolization is an effective, less invasive treatment option for patients with AAA and prohibitive operative risk. We emphasize the need for complete embolization documented by decreased aneurysm size.

The comparative influence of dietary zinc status and recombinant human interleukin-1 alpha (rhIL-1 alpha) and recombinant human interleukin-6 (rhIL-6) on metallothionein (MT) gene expression was examined in rat bone marrow and liver. Growing male rats were fed a diet with 5 (restricted), 30 (control), or 180 (supplemented) mg Zn/kg for 14 d. On d 15, rats were injected with 5 micrograms of rhIL-1 alpha or rhIL-6. Marrow metallothionein responded directly to dietary zinc but did not respond to these cytokines. Significantly less zinc accumulated in marrow from the zinc-restricted rats compared with control or supplemented rats. Analysis of metallothionein isoform mRNA expression showed MT-1 is the primary gene expressed in marrow. A significant interaction between dietary zinc and cytokine treatment was observed in the liver. Hepatic metallothionein induction following both rhIL-1 alpha and rhIL-6 injection was directly related to dietary zinc intake. Expression of hepatic metallothionein isoform mRNAs suggested MT-1 responded to zinc and MT-2 responded to cytokines. These results indicate that metallothionein gene expression in both the marrow and the liver responds to dietary zinc status. In contrast, liver metallothionein expression can be altered by these cytokines, which are known to act on many cell types. Furthermore, these results suggest that bone marrow metallothionein could be of importance in the development of marrow cells.

The influence of maternal dietary zinc intake and recombinant human interleukin-1 alpha (rhIL-1 alpha) administration on metallothionein gene expression and the distribution of 65Zn were investigated. Pregnant rats were fed diets containing 1, 5, 30 or 180 mg Zn/kg diet in an equalized regime from d 13-20 of gestation. Metallothionein gene expression was examined by Northern blot and dot blot hybridization using combined 60-mer oligonucleotides specific for rat metallothionein-1 and -2 genes. Expression was progressively depressed in the fetal livers and livers and kidneys of dams fed diets marginal (5 mg/kg) and deficient (1 mg/kg) in zinc content. Administration of rhIL-1 alpha increased expression in maternal liver, placenta and in fetal liver of dams fed adequate or deficient diets. Kinetics of intravenously administered 65Zn showed that in response to rhIL-1 alpha, there was a higher uptake by the maternal liver and bone marrow with less 65Zn uptake by bone, intestine and plasma activity compared to controls. No change was observed in 65Zn taken up by the placenta or transferred to the fetus. Alteration of metallothionein gene expression could represent, in part, the mechanism whereby altered effects of zinc metabolism and function are mediated during fetal development.