Effects of Agricultural Management Policies on the Exposure of Black-Winged Stilts (Himantopus himantopus) Chicks to Cholinesterase-Inhibiting Pesticides in Rice Fields

Levels of exposure to pesticides in rice fields can be significant depending on the environmental policies practiced. The aim of European Union integrated management policy is to reduce pesticide use and impact on environment. Rice fields provide an alternative breeding habitat for many waterbirds that are exposed to the pesticides used and therefore can be valuable indicators of their risk for wildlife. To evaluate integrated management success we examined exposure of Black-winged Stilts (Himantopus himantopus) to cholinesterase-inhibiting pesticides in rice fields under different types of management by measuring plasma cholinesterase activity. Cholinesterase activity was lower in birds sampled in (a) 2008 after a period of intense pesticide application, than in (b) 2005-2007 and 2011 in rice fields subject to integrated management in Doñana (SW Spain) and (c) in control natural wetlands in Spain and Morocco. During 2009 and 2010, cholinesterase activity was lower in rice fields in Doñana than in rice fields in Larache and Sidi Allal Tazi (NW Morocco). Our results suggest that integrated management successfully reduced the exposure of Black-winged Stilts to pesticides in most of the years. Care should be taken to implement mosquito and pest crop controls on time and with environmentally friendly products in order to reduce its impact on wildlife.     

Carvacrol Depends on Heme Oxygenase-1 (HO-1) to Exert Antioxidant,Anti-inflammatory,and Mitochondria-Related Protection in the Human Neuroblastoma SH-SY5Y Cells Line Exposed to Hydrogen Peroxide

Neurochemical Research - The link between mitochondrial dysfunction, redox impairment, and inflammation leads to increased rates of brain cells loss in neurodegenerative diseases and in affective...     

Against all odds: Numerical assessment by tufted capuchin monkeys

When competitors are able to assess the asymmetry in the resource holding potential before interacting, individuals or groups should avoid interacting with stronger opponents, thereby avoiding the energy costs and risk of injury associated with aggressive intergroup encounters. Thus, escalated aggression is expected only between closely matched competitors. Among Argentine tufted capuchin monkeys (Sapajus nigritus), intergroup dominance is decided by the asymmetry in male group size. Using playback experiments, I simulated intergroup encounters with neighboring groups, manipulating both the apparent numerical asymmetry and the resource context. During experimental trials, I recorded the approach behavior of the focal individual, as well as changes in neighbor density and individual travel speed following the presentation of the playback stimulus, to assess whether individual willingness to participate in resource defense was affected by the probability of winning the encounter. In spite of the competitive disadvantage, neither males nor females showed a decreased probability of approach when the numerical odds strongly favored the opposing group. Instead decisions regarding whether to participate appear to be driven primarily by the resource context. Nevertheless, changes in individual behavior during approaches suggest that tufted capuchin monkeys are sensitive to the relative odds. Individuals accelerated less when approaching a larger group, although no changes in neighbor density were apparent. The absence of an effect of the numerical asymmetry on willingness to approach the playback speaker suggests that subordinate groups benefit from engaging in intergroup aggression with larger neighbors, despite the high probability of losing. These encounters may serve to assess the current subjective resource valuation of the neighboring group or limit territorial expansion by large groups by decreasing the marginal value of home range exclusivity. Because these encounters are riskier, however, individuals appear to alter their approaches, becoming more tentative as the numerical odds increasingly favor the opposing group.     

Different effects of catechin on angiogenesis and inflammation depending on VEGF levels

Although physiological and pathological angiogenesis develop through similar processes, during pathological angiogenesis, proangiogenic factors are exacerbated. Polyphenols have been considered therapeutic tools for conditions exhibiting enhanced angiogenesis. However, the possibility that these compounds may also prevent vascularization in physiological situations is a major drawback for their use. The purpose of the current study was to investigate the effects of 0.1–100 μM catechin on endothelial cells (EC) and vascular smooth muscle cells (VSMC) regarding angiogenic and inflammatory processes. Catechin modulation of angiogenesis and inflammation was also evaluated in vivo using different models of angiogenesis: one physiological (skin wound-healing assay) and another one resembling pathological angiogenesis, exhibiting higher vascular endothelial growth factor (VEGF)-A stimulation (Matrigel plug assay). The in vitro results showed that 100 μM catechin increased viability (to 165.58% and to 165.34%) and decreased apoptosis (53.45% and 92.65%) and proliferation (33.19% and 23.36%) of EC and VSMC, respectively. Catechin affected migration and invasion, tending to increase both in EC and decreasing them in VSMC; however, it did not change sprouting angiogenesis. Nevertheless, catechin diminished in vitro inflammatory modulators such as tumor necrosis factor α (58.66% for human umbilical vein endothelial cells and 85.46% for human aortic smooth muscle cells) and nuclear factor kappa-B (38.43% for VSMC). The in vivo results demonstrated that catechin did not change angiogenesis and inflammation in skin wound-healing model and substantially decreased these processes in Matrigel plug assay. Altogether, the current study showed that catechin has different effects in angiogenesis and inflammation depending on VEGF-A levels. The absence of adverse effects in mature vasculature favors catechin potential use against pathological situations where angiogenesis is stimulated.     

Physiological condition and wing pigmentation expression in a damselfly with seasonal polyphenism

Secondary sexual traits can be indicators of individual condition that may present seasonal polyphenism as a result of the differential costs of expression along the season. Wing spots in male damselflies of the Calopterygidae family are secondary sexual traits associated with intrasexual competition and mate choice. Hetaerina titia Drury is a calopterygid damselfly where males show red and black wing spots, contrasting with other species of the genus whose males only express a red wing spot. In the present study, we evaluate the seasonal variation of the expression of male's red and black wing spots and their allometric patterns. Additionally, we measure male condition in the form of proteins, lipids, soluble carbohydrates and glycogen in early and late seasons. Black wing spots present higher variation than red wing spots and males of the late season are more pigmented. Allometry is positive for wing red spot in the early season and for black spot in the late season. Males of the late season present a higher concentration of proteins, soluble carbohydrates and glycogen, although there is no variation in the lipid content. The results of the present study suggest that, in H. titia males, black pigmentation replaces the function of the red pigmentation to signal condition. Both traits, however, may be heavily affected by environmental situations (e.g. food availability).     

The physical and mechanical effects of suspension-induced osteopenia on mouse long bones.

The present investigation addresses the extent of tail-suspension effects on the long bones of mice. The effects are explored in both sexes, in both forelimb and hindlimb bones, and in both diaphyseal and metaphyseal/epiphyseal bones. Two weeks of suspension provided unloading of the femora and tibiae and an altered loading of the humeri. Whole-bone effects included lower mass (approximately 10%) and length (approximately 4%) in the bones of suspended mice compared to controls. The geometric and material properties of the femora were considered along the entire length of the diaphysis and in the metaphysis/epiphysis portions as a unit. Geometric effects included lower cross-sectional cortical area (16%), cortical thickness (25%) and moment of inertia (21%) in the femora of suspended mice; these differences were observed in both distal and proximal portions of the femur diaphysis. The relative amount of bone comprising the middle 8 mm of the diaphysis was greater (3%) in the control mice than in the suspended mice. Significant mass differences between the group in the metaphysis/epiphysis were not observed. Material effects included lower %ash (approximately 2%) in the femora and tibiae as well as in the humeri of suspended mice compared to controls. With respect to the measured physical and material properties, suspension produced similar bone responses in male and female mice. The effects of suspension are manifested largely through geometric rather than through material changes.