Vicarious Nucleophilic Chloromethylation of Nitroaromatics.

Nitroaromatics substituted with electron-acceptor or electron-donor groups undergo vicarious nucleophilic substitution with the lithium salt of dichloromethane to provide chloromethyl-substituted nitroaromatics in good to high yields. The methodology represents a new strategy for the synthesis of benzyl chlorides.

Oxidative nucleophilic aromatic amination of nitrobenzenes.

Nitrobenzenes substituted with electron-acceptor groups such as halogen, nitro, trifluoromethyl, pentafluorosulfanyl, or cyano underwent oxidative nucleophilic substitution with lithium salts of arylamines to afford N-aryl-2-nitroanilines.

Case studies of conservation plans that incorporate geodiversity.

Geodiversity has been used as a surrogate for biodiversity when species locations are unknown, and this utility can be extended to situations where species locations are in flux. Recently, scientists have designed conservation networks that aim to explicitly represent the range of geophysical environments, identifying a network of physical stages that could sustain biodiversity while allowing for change in species composition in response to climate change. Because there is no standard approach to designing such networks, we compiled 8 case studies illustrating a variety of ways scientists have approached the challenge. These studies show how geodiversity has been partitioned and used to develop site portfolios and connectivity designs; how geodiversity-based portfolios compare with those derived from species and communities; and how the selection and combination of variables influences the results. Collectively, they suggest 4 key steps when using geodiversity to augment traditional biodiversity-based conservation planning: create land units from species-relevant variables combined in an ecologically meaningful way; represent land units in a logical spatial configuration and integrate with species locations when possible; apply selection criteria to individual sites to ensure they are appropriate for conservation; and develop connectivity among sites to maintain movements and processes. With these considerations, conservationists can design more effective site portfolios to ensure the lasting conservation of biodiversity under a changing climate.

The role of hypothyroidism in the etiology and progression of dilated cardiomyopathy in Doberman Pinschers.

BACKGROUND: Hypothyroidism and dilated cardiomyopathy (DCM) are both common diseases in Doberman Pinschers. A possible influence of hypothyroidism on the etiology and progression of DCM is controversial. OBJECTIVES: Evaluation of the role of hypothyroidism in etiology and progression of DCM. ANIMALS: A total of 175 Doberman Pinschers. METHODS: In this longitudinal prospective study, echocardiography and 24-hour ambulatory ECG recordings were performed in all dogs as screening tests for DCM. Total thyroxine (TT4 ) and thyroid ultrasonography served as initial screening tests for hypothyroidism and low TT4 values were followed up by a thyroid stimulating hormone (TSH) test or free total thyroxine (fT4 )/cTSH measurements. Additionally, a follow-up study of dogs affected by both DCM and hypothyroidism under optimal treatment for hypothyroidism was conducted. RESULTS: A total of 107 dogs were healthy, 45 dogs had DCM, 11 hypothyroidism, and 12 dogs had both DCM and hypothyroidism. TT4 values as well as the thyroid volumes were equivalent in the healthy dogs and in those with DCM. Neither ventricular premature complexes nor echocardiographic parameters differed between healthy and hypothyroid dogs. Dogs with DCM had a 2.26-fold (CI0.95 = 1.1-4.8) higher risk of also being affected by hypothyroidism. Despite optimal thyroid treatment of dogs with hypothyroidism and DCM, there was a progression of the heart disease. CONCLUSIONS AND CLINICAL IMPORTANCE: This study did not confirm a role of hypothyroidism in the etiology or progression of DCM. Treatment of hypothyroidism did not improve the clinical outcome.

Habitat barriers limit gene flow and illuminate historical events in a wide-ranging carnivore, the American puma.

We examined the effects of habitat discontinuities on gene flow among puma (Puma concolor) populations across the southwestern USA. Using 16 microsatellite loci, we genotyped 540 pumas sampled throughout the states of Utah, Colorado, Arizona, and New Mexico, where a high degree of habitat heterogeneity provides for a wide range of connective habitat configurations between subpopulations. We investigated genetic structuring using complementary individual- and population-based analyses, the latter employing a novel technique to geographically cluster individuals without introducing investigator bias. The analyses revealed genetic structuring at two distinct scales. First, strikingly strong differentiation between northern and southern regions within the study area suggests little migration between them. Second, within each region, gene flow appears to be strongly limited by distance, particularly in the presence of habitat barriers such as open desert and grasslands. Northern pumas showed both reduced genetic diversity and greater divergence from a hypothetical ancestral population based on Bayesian clustering analyses, possibly reflecting a post-Pleistocene range expansion. Bayesian clustering results were sensitive to sampling density, which may complicate inference of numbers of populations when using this method. The results presented here build on those of previous studies, and begin to complete a picture of how different habitat types facilitate or impede gene flow among puma populations.

Identification of the respiratory syncytial virus-induced immunosuppressive factor produced by human peripheral blood mononuclear cells in vitro as interferon-alpha.

Respiratory syncytial virus (RSV) can inhibit the proliferative response of human peripheral blood mononuclear cells (PBMC) in vitro. This inhibition is mediated by an extracellular RSV-induced factor. In the present study, the factor was clearly identified as interferon (IFN)-alpha. The RSV-induced IFN-alpha bound strongly to PBMC and inhibited the anti-RSV proliferative response only when added within the first few days of stimulation. There was, however, no concomitant decrease in the production of interleukin (IL)-2 nor in the cell surface expression of CD25, CD71, and HLA-DR. Inhibition by RSV-induced IFN-alpha was unrelated to the levels of IL-1, -2, and -6 or of IFN-gamma induced by RSV in vitro or to the presence of IL-1 inhibitor, tumor necrosis factor-alpha, prostaglandin, or IL-10. Immunosuppression by IFN-alpha may significantly affect the outcome of infection and reinfection with RSV.

Infectious respiratory syncytial virus (RSV) effectively inhibits the proliferative T cell response to inactivated RSV in vitro.

The effect of respiratory syncytial virus (RSV) on the cellular immune response of human mononuclear cells in vitro was examined. Inhibition by RSV of the lymphocyte response to phytohemagglutinin in vitro was confirmed using cells from human umbilical cord blood. In addition, RSV significantly inhibited both the proliferative and T cell colony responses of human mononuclear cells to Epstein-Barr virus. An RSV-specific cellular immune response was induced in vitro by stimulation of mononuclear cells from RSV-seropositive donors with beta-propiolactone-inactivated RSV. This RSV-specific response was significantly inhibited by infectious RSV itself, and the inhibition was mediated by an extracellular factor produced by RSV-infected mononuclear cells. A similar inhibition in vivo of the RSV-induced cellular immune response may contribute significantly to delayed recovery from primary infection and to reduced resistance to subsequent infections.