Determination of irritant threshold concentrations to weeds,trees and grasses through serial dilutions in intradermal testing on healthy clinically nonallergic dogs

Irritant threshold concentration (ITC) for intradermal testing (IDT) was determined in 31 healthy, clinically nonallergic dogs. Twenty‐three allergens were tested at five variable concentrations ranging from 1000 to 8000 PNU/mL. To distinguish irritant reactions from subclinical IgE‐mediated hypersensitivities, serum allergy testing was performed. ITCs were determined by evaluating the lowest concentration to which no dogs (0% cut‐off) and to which at least 10% of dogs (≥10% cut‐off) reacted. ITCs at the 0% cut‐off were: 1000 PNU/mL (Johnson grass), 2000 PNU/mL (Ash, Lamb’s Quarter and Bermuda), 3000 PNU/mL (Bahia, Rye, Pig Weed and Virginia Oak), 4000 PNU/mL (Marsh Elder and Maple), 5000 PNU/mL (Sorrel sheep) and 7000 PNU/mL (Cocklebur and Black Willow). ITC for Dog Fennel, Box Elder and Red Cedar was <1000 PNU/mL. ITCs at the ≥10% cut‐off were: 2500 PNU/mL (Johnson), 3000 PNU/mL (Box Elder), 5000 PNU/mL (Bahia), 6000 PNU/mL (Pigweed and Marsh Elder) and 8000 PNU/mL (Virginia Oak and Black Willow). For all other allergens, the ITC was >8000 PNU/mL and could not be determined. No significant agreement between positive values was found for the same allergen on IDT and serum allergy testing for each dog suggesting reactions caused by the determined ITCs are less likely subclinical IgE‐mediated reactions. These results suggest that ITCs may vary, also they may be very high for the allergens tested and that higher test concentrations may be used for IDT for the tested allergens without inducing an irritant reaction. Further studies are needed to evaluate the benefit of higher IDT concentrations in atopic dogs.     

Foraging by burrowing parrots has little impact on agricultural crops in northeastern Patagonia,Argentina

Conflicts between wildlife and agriculture have increased as cultivation has expanded into previously unexploited areas. As frequent consumers of such crops, parrots (Psittaciformes) are often persecuted, despite the lack of measured economic impacts they may cause. This situation has compromised attempts to manage potential damage and endangered parrot populations. Here, we evaluate and measure actual crop damage and characterize the foraging areas used by the burrowing parrot (Cyanoliseus patagonus) in northeastern Patagonia, Argentina. We found that damage to field crops was economically insignificant, affecting 0.1%–0.4% of the sunflower harvest, with no damage detected in other more important crops in the region. The parrots mainly consumed grain left or spilled after harvesting, and unharvested grain from cultivated pastures and road margins. This grain represents a loss attributable to harvest machines, being independent from the presence of parrots. Given the negligible damage measured here, we conclude that there is no need for management of parrots as crop pests in northeastern Patagonia. Our study provides further support to the view that parrot damage has been often exaggerated and overstated.     

Evaluation of key odorants in sauvignon blanc wines using three different methodologies

In this study three different approaches were employed to identify key odorants in Sauvignon blanc wines. First, the concentrations of the odorants were compared to their respective aroma detection thresholds. The resulting odor activity values (OAV) were transformed into a normalized and weighted measure that allows the aroma profiles of different wines to be compared and the contribution of a single aroma in a complex mixture to be evaluated. Based on their OAV, 3-mercaptohexanol and 3-mercaptohexyl acetate were the two most important aroma compounds in many Marlborough Sauvignon blanc wines. Due to limitations with the OAV approach, the study was extended to include aroma extract dilution analysis (AEDA), which revealed that β-damascenone, together with the varietal thiols, esters, and higher alcohols, are key odorants in Sauvignon blanc wines. The final approach undertaken was aroma reconstitution and omission tests using a deodorized wine base and the creation of a model Marlborough Sauvignon blanc. Single compounds and groups of compounds were omitted from the model to study their impact on the sensory properties of the model wine. Reconstitution and omission confirmed that varietal thiols, esters, terpenes, and β-damascenone are all important contributors to Sauvignon blanc aroma. The methoxypyrazines showed an important but relatively low impact in all three of the approaches undertaken in this study.     

Treatment of Selenium in Simulated Refinery Effluent Using a Pilot-Scale Constructed Wetland Treatment System

Water, Air, &; Soil Pollution - Effective and reliable treatment is needed to treat selenium (Se) in petroleum refinery effluents to meet water discharge limits established under the Clean Water...     

Characterizing the Anti-HIV Activity of Papuamide A

Papuamide A is representative of a class of marine derived cyclic depsipeptides, reported to have cytoprotective activity against HIV-1 in vitro. We show here that papuamide A acts as an entry inhibitor, preventing human immunodeficiency virus infection of host cells and that this inhibition is not specific to R5 or X4 tropic virus. This inhibition of viral entry was determined to not be due to papuamide A binding to CD4 or HIV gp120, the two proteins involved in the cell-virus recognition and binding. Furthermore, papuamide A was able to inhibit HIV pseudotype viruses expressing envelope glycoproteins from vesicular stomatitis virus or amphotropic murine leukemia virus indicating the mechanism of viral entry inhibition is not HIV-1 envelope glycoprotein specific. Time delayed addition studies with the pseudotyped viruses show that papuamide A inhibits viral infection only at the initial stage of the viral life cycle. Additionally, pretreatment studies revealed that the virus, and not the cell, is the target of papuamide A’s action. Together, these results suggest a direct virucidal mechanism of HIV-1 inhibition by papuamide A. We also demonstrate here that the other papuamides (B-D) are able to inhibit viral entry indicating that the free amino moiety of 2,3-diaminobutanoic acid residue is not required for the virucidal activity.     

Characterization of seabird bycatch in eastern Canadian waters, 1998–2011, assessed from onboard fisheries observer data

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