Distinct evolutionary lineages of Schistocephalus parasites infecting co-occurring sculpin and stickleback fishes in Alaska.

Sculpins (coastrange and slimy) and sticklebacks (ninespine and threespine) are widely distributed fishes cohabiting 2 south-central Alaskan lakes (Aleknagik and Iliamna), and all these species are parasitized by cryptic diphyllobothriidean cestodes in the genus Schistocephalus. The goal of this investigation was to test for host-specific parasitic relationships between sculpins and sticklebacks based upon morphological traits (segment counts) and sequence variation across the NADH1 gene. A total of 446 plerocercoids was examined. Large, significant differences in mean segment counts were found between cestodes in sculpin (mean = 112; standard deviation [s.d.] = 15) and stickleback (mean = 86; s.d. = 9) hosts within and between lakes. Nucleotide sequence divergence between parasites from sculpin and stickleback hosts was 20.5%, and Bayesian phylogenetic analysis recovered 2 well-supported clades of cestodes reflecting intermediate host family (i.e. sculpin, Cottidae vs stickleback, Gasterosteidae). Our findings point to the presence of a distinct lineage of cryptic Schistocephalus in sculpins from Aleknagik and Iliamna lakes that warrants further investigation to determine appropriate evolutionary and taxonomic recognition.

Racial Differences in Pediatric Emergency Department Triage Scores.

BACKGROUND: Racial disparities are frequently reported in emergency department (ED) care. OBJECTIVES: To examine racial differences in triage scores of pediatric ED patients. We hypothesized that racial differences existed but could be explained after adjusting for sociodemographic and clinical factors. METHODS: We examined all visits to two urban, pediatric EDs between August 2009 and March 2010. Demographic and clinical data were electronically extracted from the medical record. We used logistic regression to analyze racial differences in triage scores, controlling for possible covariates. RESULTS: There were 54,505 ED visits during the study period, with 7216 (13.2%) resulting in hospital admission. White patients accounted for 36.4% of visits, African Americans 28.5%, Hispanics 18.0%, Asians 4.1%, and American Indians 1.8%. After adjusting for potential confounders, African American (adjusted odds ratio [aOR] 1.89, 95% confidence interval [CI] 1.69-2.12), Hispanic (aOR 1.77, 95% CI 1.55-2.02), and American Indian (aOR 2.57, 95% CI 1.80-3.66) patients received lower-acuity triage scores than Whites. In three out of four subgroup analyses based on presenting complaints (breathing difficulty, abdominal pain, fever), African Americans and Hispanics had higher odds of receiving low-acuity triage scores. No racial differences were detected for patients with presenting complaints of laceration/head injury/arm injury. However, among patients admitted to the hospital, African Americans (aOR 1.47, 95% CI 1.13-1.90) and Hispanics (aOR 1.71, CI 1.22-2.39) received lower-acuity triage scores than Whites. CONCLUSION: After adjusting for available sociodemographic and clinical covariates, African American, Hispanic, and American Indian patients received lower-acuity triage scores than Whites.

Fishing for ecosystem services.

Ecosystems are commonly exploited and manipulated to maximize certain human benefits. Such changes can degrade systems, leading to cascading negative effects that may be initially undetected, yet ultimately result in a reduction, or complete loss, of certain valuable ecosystem services. Ecosystem-based management is intended to maintain ecosystem quality and minimize the risk of irreversible change to natural assemblages of species and to ecosystem processes while obtaining and maintaining long-term socioeconomic benefits. We discuss policy decisions in fishery management related to commonly manipulated environments with a focus on influences to ecosystem services. By focusing on broader scales, managing for ecosystem services, and taking a more proactive approach, we expect sustainable, quality fisheries that are resilient to future disturbances. To that end, we contend that: (1) management always involves tradeoffs; (2) explicit management of fisheries for ecosystem services could facilitate a transition from reactive to proactive management; and (3) adaptive co-management is a process that could enhance management for ecosystem services. We propose adaptive co-management with an ecosystem service framework where actions are implemented within ecosystem boundaries, rather than political boundaries, through strong interjurisdictional relationships.

Does initial length of stay impact 30-day readmission risk in pediatric asthma patients?

OBJECTIVES: Accountable care puts pressure on hospitals to manage care episodes. Initial length of stay (ILOS) and readmission risk are important elements of a care episode and measures of care quality. Understanding the association between these two measures can guide hospital efforts in managing care episodes. This study was designed to explore the association between ILOS and readmission risk in a cohort of pediatric asthma patients. MATERIALS AND METHODS: The sample cohort (n = 4965) consisted of all asthma patients discharged from Children's Hospitals and Clinics of Minnesota (CHC MN) from January 2008 through August 2012. Asthma discharges included cases with a principal diagnosis of asthma or certain respiratory cases with asthma listed as a secondary diagnosis. Multiple logistic regression was used to test associations, adjusting for covariates. RESULTS: Adjusting for covariates, we found no significant association between ILOS and readmission (OR: 1.04 [95% CI: 0.98-1.10]). Analyzing ILOS categorically by length of stay, one-day stays did not have a significantly higher readmission risk (OR:1.27 [95% CI: 0.87-1.85]) than two-day stays, which had the lowest observed readmission risk. Risk increased as ILOS exceeded two days but was not significantly different by day. We found no association when comparing the difference in actual versus expected ILOS and readmission risk (shorter than expected OR: 1.13 [95% CI: 0.74-1.71]; longer than expected OR: 0.97 [95% CI: 0.69-1.38]). CONCLUSIONS: Attempts to prolong ILOS would dramatically increase costs with little impact on readmissions. For example, increasing one-day visits to two-day visits would increase hospital patient days 38% (1870 d) in this cohort while decreasing total readmissions by 3.8% [95% CI: 3.6-4.0%]. Understanding the mechanisms that impact readmissions is essential in evaluating cost-effective approaches to improving patient outcomes and lowering the cost of care.

Cell-by-cell dissection of gene expression and chromosomal interactions reveals consequences of nuclear reorganization.

The functional consequences of long-range nuclear reorganization were studied in a cell-by-cell analysis of gene expression and long-range chromosomal interactions in the Drosophila eye and eye imaginal disk. Position-effect variegation was used to stochastically perturb gene expression and probe nuclear reorganization. Variegating genes on rearrangements of Chromosomes X, 2, and 3 were probed for long-range interactions with heterochromatin. Studies were conducted only in tissues known to express the variegating genes. Nuclear structure was revealed by fluorescence in situ hybridization with probes to the variegating gene and heterochromatin. Gene expression was determined alternately by immunofluorescence against specific proteins and by eye pigment autofluorescence. This allowed cell-by-cell comparisons of nuclear architecture between cells in which the variegating gene was either expressed or silenced. Very strong correlations between heterochromatic association and silencing were found. Expressing cells showed a broad distribution of distances between variegating genes and their own centromeric heterochromatin, while silenced cells showed a very tight distribution centered around very short distances, consistent with interaction between the silenced genes and heterochromatin. Spatial and temporal analysis of interactions with heterochromatin indicated that variegating genes primarily associate with heterochromatin in cells that have exited the cell cycle. Differentiation was not a requirement for association, and no differences in association were observed between cell types. Thus, long-range interactions between distal chromosome regions and their own heterochromatin have functional consequences for the organism.

Variation in angler distribution and catch rates of stocked rainbow trout in a small reservoir.

We investigated the spatial and temporal relationship of catch rates and angler party location for two days following a publicly announced put-and-take stocking of rainbow trout (Oncorhynchus mykiss). Catch rates declined with time since stocking and distance from stocking. We hypothesized that opportunity for high catch rates would cause anglers to fish near the stocking location and disperse with time, however distance between angler parties and stocking was highly variable at any given time. Spatially explicit differences in catch rates can affect fishing quality. Further research could investigate the variation between angler distribution and fish distribution within a waterbody.

Suppression of Epstein-Barr nuclear antigen 1 (EBNA1) by RNA interference inhibits proliferation of EBV-positive Burkitt's lymphoma cells.

PURPOSE: Epstein-Barr virus (EBV) is associated with the development of several lymphoid and epithelial malignancies, including Burkitt's lymphoma. The EBV latent protein, EBV Nuclear Antigen 1 (EBNA1), is detectable in almost all types of EBV-associated tumors and is essential for replication and maintenance of the latent episome of EBV. We here examined whether the RNA interference (RNAi) technique could be employed to suppress expression of EBNA1 in EBV-positive Burkitt's lymphoma cells. METHODS: A Raji cell line expressing small hairpin RNAs (shRNAs) against EBNA1 was established and EBNA1 mRNA level was determined by real-time RT-PCR analysis. We investigated the effects of EBNA1 silence on lymphoma cell growth and cell cycle progression. RESULTS: Transfection of an EBNA1 RNAi plasmid resulted in substantial loss of EBNA1 mRNA and significantly inhibited proliferation of Raji cells relative to the control plasmid case. Suppression of EBNA1 was also associated with downregulation of EBV oncogene EBNA2, a decreased PCNA labeling index and increased G0/G1 fraction in cell cycle analysis. CONCLUSIONS: These findings point to potential therapeutic applications for vector-mediated siRNA delivery to control EBV-associated malignant disorders.

Variability in Implementation of Interventions Aimed at Reducing Readmissions Among Patients With Heart Failure: A Survey of Teaching Hospitals.

PURPOSE: To highlight teaching hospitals' efforts to reduce readmissions by describing interventions implemented to improve care transitions for heart failure (HF) patients and the variability in implemented HF-specific and care transition interventions. METHOD: In 2012, the authors surveyed a network of 17 teaching hospitals to capture information about the number, type, stage of implementation, and structure of 4 HF-specific and 21 care transition (predischarge, bridging, and postdischarge) interventions implemented to reduce readmissions among patients with HF. The authors summarized data using descriptive statistics, including the mean number of interventions implemented and the frequency and stage of specific interventions, and descriptive plots of the structure of two common interventions (multidisciplinary rounds and follow-up telephone calls). RESULTS: Sixteen hospitals (94%) responded. The number and stage of implementation of the HF-specific and care transition interventions implemented varied across institutions. The mean number of interventions at an advanced stage of implementation (i.e., implemented for ≥ 75% of HF patients on the cardiology service or on all services) was 10.9 (standard deviation = 4.3). Overall, predischarge interventions were more common than bridging or postdischarge interventions. There was variability in the personnel involved in multidisciplinary rounds and in the processes/content of follow-up telephone calls. CONCLUSIONS: Teaching hospitals have implemented a wide range of interventions aimed at reducing hospital readmissions, but there is substantial variability in the types, stages, and structure of their interventions. This heterogeneity highlights the need for collaborative efforts to improve understanding of intervention effectiveness.

A novel method for detecting inpatient pediatric asthma encounters using administrative data.

Multiple methods for detecting asthma encounters are used today in public surveillance, quality reporting, and clinical research. Failure to detect asthma encounters can make it difficult to measure the scope and effectiveness of hospital or community-based interventions important in comparative effectiveness research and accountable care. Given the pairing of asthma with certain respiratory conditions, the objective of this study was to develop and test an asthma detection algorithm with specificity and sensitivity using 2 criteria: (1) principal discharge diagnosis and (2) asthma diagnosis code position. A medical record review was conducted (n=191) as the gold standard for identifying asthma encounters given objective criteria. The study team observed that for certain principal respiratory diagnoses (n=110), the observed odds ratio that encounters were for asthma when asthma was coded in the second or third code position was not significantly different than when asthma was coded as the principal diagnosis, 0.36 (P=0.42) and 0.18 (P=0.14), respectively. In contrast, the observed odds ratio was significantly different when asthma was coded in the fourth or fifth positions (P<.001). This difference remained after adjusting for covariates. Including encounters with asthma in 1 of the 3 first positions increased the detection sensitivity to 0.84 [95% confidence interval (CI): 0.76-0.92] while increasing the false positive rate to 0.19 [95% CI: 0.07-0.31]. Use of the proposed algorithm significantly improved the reporting accuracy [0.83 95%CI:0.76-0.90] over use of (1) the principal diagnosis alone [0.55 95% CI:0.46-0.64] or (2) all encounters with asthma 0.66 [95% CI:0.57-0.75]. Bed days resulting from asthma encounters increased 64% over use of the principal diagnosis alone. Given these findings, an algorithm using certain respiratory principal diagnoses and asthma diagnosis code position can reliably improve asthma encounter detection for population-based health impact measurement.

Basal chromatin modification at the IL-4 gene in helper T cells.

Chromatin immunoprecipitations in naive CD4, but not CD8, T cells, demonstrated association of the IL-4 promoter with acetylated histone. Histone modifications and rapid IL-4 transcription were absent in conserved noncoding sequence 1 (CNS-1)(-/-) cells lacking an 8-kb-distant enhancer in the IL-4/IL-13 intergenic region, but also in CD4(-/-) and Itk(-/-) cells, which have similar Th2 deficiencies. Histones associated with the IL-13 promoter were not similarly acetylated in naive T cells, but became acetylated in differentiated Th2 cells. Conversely, Th1 differentiation induced histone methylation at the type 2 cytokine locus. Like CD4(-/-) and Itk(-/-) mice, CNS-1(-/-) BALB/c mice were highly resistant to the Th2-inducing protozoan, Leishmania major. CNS-1 deficiency led to failure of IL-4 gene repositioning to heterochromatin after Th1 polarization, possibly related to the presence of reiterative Ikaros binding sites in the intergenic element. Hyperacetylation of nonexpressed genes may serve to mark lineage-specific loci for rapid expression and further modification.