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The use of plant protection products (PPPs) in agricultural areas implies potential chemical loadings to surface waters, which can pose a risk to aquatic ecosystems and human health. Due to the spatio-temporal variability of PPP applications and of the processes regulating their transport to surface waters, aquatic organisms are typically exposed to pulses of contaminants. In small mountain watersheds, where runoff fluxes are more rapid due to the steep slopes, such exposure peaks are particularly likely to occur. In this work, a spatially explicit, dynamic model for predicting pesticide exposure in surface waters of cultivated mountain basins (DynAPlus) has been developed. The model has been applied to a small mountain watershed (133 km2) located in the Italian Eastern Alps and characterized by intensive agriculture (apple orchards) around the main river and its tributaries. DynAPlus performance was evaluated for chlorpyrifos through experimental monitoring, using samples collected during the 2011 and 2012 productive seasons. The comparison between predictions and measurements resulted in a good agreement (R2 = 0.49, efficiency factor 0.60), although a more accurate spatial information in the input scenario (e.g., field-specific applications, rainfall amount, soil properties) would dramatically improve model performance. A set of illustrative simulations performed for three PPPs highlighted the potential role of DynAPlus in improving exposure predictions for ecological risk assessment and pesticide management practices (e.g., for active ingredient and application rate selection), as well as for planning efficient monitoring campaigns and/or interpreting monitoring data. However, some model improvements (e.g., solid erosion and transport) and a more thorough model validation are desirable to enlarge the applicability domain.

Objectives: To describe the first in-depth analysis of both the T-cell responses against human herpesvirus-8 (HHV-8) and the HHV-8 viral load in 1 patient who developed iatrogenic HHV-8-associated-Kaposi's sarcoma (KS) following immunosuppressive treatment for undifferentiated arthritis and to review the literature on iatrogenic KS (IKS). Methods: T-cell responses against HHV-8 lytic and latent antigens were analyzed by ex vivo enzyme-linked immunospot (Elispot) and HHV-8 viral load was assessed by quantitative polymerase chain reaction, in sequential peripheral blood samples from a 55-year-old woman who developed skin/mucosal and visceral KS, while receiving treatment with cyclosporine, methotrexate, and methylprednisolone for undifferentiated arthritis. Results: KS may result from HHV-8 infection in patients undergoing immunosuppressive treatment for rheumatic diseases and this is the first case of IKS occurring in undifferentiated arthritis. A role for immune surveillance in the pathogenesis of IKS is supported by the observation of disease regression following discontinuation of immunosuppressive therapy. In a 4-year follow-up, we showed that variations of the virus-specific immune responses but not of the viral load correlated well with the disease course, characterized by 2 remission and subsequent relapse phases, following changes of immunosuppressive therapy. Conclusions: We have provided evidence of a clear-cut correlation between changes in immunologic markers of HHV-8 infection and the disease course of this viral associated tumor, concomitant with variations of immunosuppressive treatment. Thus, ex vivo enzyme-linked immunospot for HHV-8-specific T-cell responses represents a new tool for the clinical management of rheumatic patients with IKS. (C) 2009 Elsevier Inc. All rights reserved. Semin Arthritis Rheum 39:170-175 RI Rossi, Giulio/C-5576-2011