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Mountain lions (Puma concolor) throughout North and South America are infected with puma lentivirus clade B (PLVB). A second, highly divergent lentiviral clade, PLVA, infects mountain lions in southern California and Florida. Bobcats (Lynx rufus) in these two geographic regions are also infected with PLVA, and to date, this is the only strain of lentivirus identified in bobcats. We sequenced full-length PLV genomes in order to characterize the molecular evolution of PLV in bobcats and mountain lions. Low sequence homology (88% average pairwise identity) and frequent recombination (1 recombination breakpoint per 3 isolates analyzed) were observed in both clades. Viral proteins have markedly different patterns of evolution; sequence homology and negative selection were highest in Gag and Pol and lowest in Vif and Env. A total of 1.7% of sites across the PLV genome evolve under positive selection, indicating that host-imposed selection pressure is an important force shaping PLV evolution. PLVA strains are highly spatially structured, reflecting the population dynamics of their primary host, the bobcat. In contrast, the phylogeography of PLVB reflects the highly mobile mountain lion, with diverse PLVB isolates cocirculating in some areas and genetically related viruses being present in populations separated by thousands of kilometers. We conclude that PLVA and PLVB are two different viral species with distinct feline hosts and evolutionary histories. Importance: An understanding of viral evolution in natural host populations is a fundamental goal of virology, molecular biology, and disease ecology. Here we provide a detailed analysis of puma lentivirus (PLV) evolution in two natural carnivore hosts, the bobcat and mountain lion. Our results illustrate that PLV evolution is a dynamic process that results from high rates of viral mutation/recombination and host-imposed selection pressure.

Purpose of the Study: Two consumer-derived measures of nursing home quality that have been underutilized by researchers are consumer complaints to the state certification agency between inspections and complaints to the Long-Term Care Ombudsman Program. This article describes these complaints, considers facility-level predictors of complaints, and examines how complaints to the 2 entities are related. Design and Methods: This article uses North Carolina complaint data from the state certification agency and Ombudsman from 2002 to 2006. First, we outline the similarities and differences in the 2 complaint sources by considering descriptive statistics and examining the structure of the 2 agencies. Second, we examine the relationship between complaints and facility characteristics that have been predictive of traditional quality measures. Finally, we examine the relationships between the 2 types of complaints. Results: We find that complaints to the 2 agencies exhibit distinct differences in substantiation rates, although the top complaint category for both agencies is quality of care. Having a higher proportion of Medicaid residents is generally not predictive of complaint volume, whereas having a higher proportion of Medicare residents is associated with higher complaint levels. Implications: We find a lack of association between complaints to the 2 agencies when examining specific matched categories of complaints in many cases, suggesting that the 2 entities are not duplicating efforts in these categories.

Feline infectious peritonitis (FIP) is an uncommon, fatal, progressive, and immune-augmented disease of cats caused by feline coronavirus (FCoV) infection. Although FCoV is common in most domestic, feral, and nondomestic [...]

From 2002 through 2005, an outbreak of feline leukemia virus (FeLV) occurred in Florida panthers (Puma concolor coryi). Clinical signs included lymphadenopathy, anemia, septicemia, and weight loss; 5 panthers died. [...]

Objectives. The purpose of this study was to determine the extent to which observed differences between White and African American nursing home residents in having an advance directive are attributable to differences between the groups in personal characteristics, the organizational environment of the nursing home, and the geographical environment of the counties in which the nursing homes are located. Methods. By using the Medical Expenditure Panel Survey Nursing Home Component matched with county-level measures from the Area Resource File, we modeled the probability of having an advance directive as a function of nursing home resident, facility, and county characteristics for African American and White residents. Results. The probability of having an advance directive was 27.0% for African American residents and 63.6% for White residents. Nearly half of this 36.6 percentage point gap could be explained by group differences in personal, facility, and county characteristics. Discussion. County characteristics play a more prominent role than do personal or facility measures in explaining the observed ethnic gap in the prevalence of advance directives. Additional studies should focus further on geographic, health status, and attitudinal variations among nursing home residents that may account for the remaining ethnic difference in the prevalence of advance directives among nursing home residents.

Abstract Background As we enter an era when testing millions of SNPs in a single gene association study will become the standard, consideration of multiple comparisons is an essential part of determining statistical significance. Bonferroni adjustments can be made but are conservative due to the preponderance of linkage disequilibrium (LD) between genetic markers, and permutation testing is not always a viable option. Three major classes of corrections have been proposed to correct the dependent nature of genetic data in Bonferroni adjustments: permutation testing and related alternatives, principal components analysis (PCA), and analysis of blocks of LD across the genome. We consider seven implementations of these commonly used methods using data from 1514 European American participants genotyped for 700,078 SNPs in a GWAS for AIDS. Results A Bonferroni correction using the number of LD blocks found by the three algorithms implemented by Haploview resulted in an insufficiently conservative threshold, corresponding to a genome-wide significance level of α = 0.15 - 0.20. We observed a moderate increase in power when using PRESTO, SLIDE, and simpleℳ when compared with traditional Bonferroni methods for population data genotyped on the Affymetrix 6.0 platform in European Americans (α = 0.05 thresholds between 1 × 10-7 and 7 × 10-8). Conclusions Correcting for the number of LD blocks resulted in an anti-conservative Bonferroni adjustment. SLIDE and simpleℳ are particularly useful when using a statistical test not handled in optimized permutation testing packages, and genome-wide corrected p-values using SLIDE, are much easier to interpret for consumers of GWAS studies.

Abstract Background Feline immunodeficiency virus (FIV) naturally infects multiple species of cat and is related to human immunodeficiency virus in humans. FIV infection causes AIDS-like disease and mortality in the domestic cat (Felis catus) and serves as a natural model for HIV infection in humans. In African lions (Panthera leo) and other exotic felid species, disease etiology introduced by FIV infection are less clear, but recent studies indicate that FIV causes moderate to severe CD4 depletion. Results In this study, comparative genomic methods are used to evaluate the full proviral genome of two geographically distinct FIV subtypes isolated from free-ranging lions. Genome organization of FIVPle subtype B (9891 bp) from lions in the Serengeti National Park in Tanzania and FIVPle subtype E (9899 bp) isolated from lions in the Okavango Delta in Botswana, both resemble FIV genome sequence from puma, Pallas cat and domestic cat across 5' LTR, gag, pol, vif, orfA, env, rev and 3'LTR regions. Comparative analyses of available full-length FIV consisting of subtypes A, B and C from FIVFca, Pallas cat FIVOma and two puma FIVPco subtypes A and B recapitulate the species-specific monophyly of FIV marked by high levels of genetic diversity both within and between species. Across all FIVPle gene regions except env, lion subtypes B and E are monophyletic, and marginally more similar to Pallas cat FIVOma than to other FIV. Sequence analyses indicate the SU and TM regions of env vary substantially between subtypes, with FIVPle subtype E more related to domestic cat FIVFca than to FIVPle subtype B and FIVOma likely reflecting recombination between strains in the wild. Conclusion This study demonstrates the necessity of whole-genome analysis to complement population/gene-based studies, which are of limited utility in uncovering complex events such as recombination that may lead to functional differences in virulence and pathogenicity. These full-length lion lentiviruses are integral to the advancement of comparative genomics of human pathogens, as well as emerging disease in wild populations of endangered species.

The structures of Mo3O6, Mo2WO6, MoW2O6, and W3O6 and their associated anions were studied using a combination of anion photoelectron (PE) spectroscopy and density functional theory calculations. The 3.49 eV photon energy anion PE spectra of all four species showed broad electronic bands with origins near 2.8 eV. Calculations predict that low-spin, cyclic structures are the lowest energy isomers for both the anion and neutral species. The lowest energy neutral structures for all four species are analogous, C3v (Mo3O6 and W3O6) or Cs (mixed clusters) symmetry structures in which all three metal atoms are in formally equivalent oxidation states, with singlet ground electronic states. The lowest energy isomers predicted for Mo3O6- and W3O6- are the same with doublet electronic states. The lowest energy structures calculated for the mixed anions are lower symmetry, with the tungsten centers in higher oxidation states than the molybdenum centers. However, Cs symmetry structures are competitive, and appear to be the primary contributors to the observed spectra. Spectral simulations based on calculated spectroscopic parameters validate the assignments. This series of clusters is strikingly different from the Mo2O4/MoWO4/W2O4 anion and neutral series described recently [Mayhall et al., J. Chem. Phys. 130, 124313 (2009)]. While the average oxidation state is the same for both series, the structures determined for the Mo2O4/MoWO4/W2O4 anions and neutrals were dissimilar and lower symmetry, and high spin states were energetically favored. This difference is attributed to the large stabilizing effect of electronic delocalization in the more symmetric trimetallic cyclic structures that is not available in the bimetallic species. [ABSTRACT FROM AUTHOR]

Addition of H2O and D2O to small tungsten suboxide cluster anions WxOy- (x=1–4; y≤3x) was studied using mass spectrometric measurements from a high-pressure fast flow reactor. Within the WOy- mass manifold, which also includes WO4H-, product masses correspond to the addition of one to three H2O or D2O molecules. Within the W2Oy- cluster series, product distributions suggest that sequential oxidation W2Oy-+H2O/D2O→W2Oy+1-+H2/D2 occurs for y<5, while for W2O5-, W2O6H2-/W2O6D2- is primarily produced. W2O6- does not appear reactive. For the W3Oy- cluster series, sequential oxidation with H2 and D2 production occurs for y<6, while W3O6- and W3O7- produce W3O7H2-/W3O7D2- and W3O8H2-/W3O8D2-, respectively. Lower mass resolution in the W4Oy- mass range prevents definitive product assignments, but intensity patterns suggest that sequential oxidation with H2/D2 evolution occurs for y<6, while W4Oy+1H2-/W4Oy+1D2- products result from addition to W4O6- and W4O7-. Based on bond energy arguments, the H2/D2 loss reaction is energetically favored if the new O–WxOy- bond energy is greater than 5.1 eV. The relative magnitude of the rate constants for sequential oxidation and H2O/D2O addition for the x=2 series was determined. There are no discernable differences in rate constants for reactions with H2O or D2O, suggesting that the H2 and D2 loss from the lower-oxide/hydroxide intermediates is very fast relative to the addition of H2O or D2O. [ABSTRACT FROM AUTHOR]