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Given the negative environmental effects of conventional agricultural techniques, the need for biodiversity-friendly agriculture systems that rely more on ecosystem services and less on chemical inputs is becoming increasingly urgent. In this paper, we focus on crop protection strategies that are alternatives to the use of pesticides. Diversification of the plant component of agricultural areas at different space and time scales has been presented as a powerful socio-economic and agro-ecological mechanism for the sustainable control of pests. Our interdisciplinary group of scientific experts examined the literature on the ecological effects of plant diversification on pests and their natural enemies, as well as the social science literature on the conditions for farmers to adopt the corresponding practices, to assess the potential offered by plant diversification. We developed a conceptual framework that connects the agro-ecological and socio-economic components of an agricultural landscape in a dynamic loop accounting for interactions among elements at different spatial and temporal scales and their feedback effects. This article presents this framework and illustrates its application to the case of wheat production and protection. By explicitly connecting each level of agro-ecological organization with the potential socio-economic drivers and limitations underpinning the adoption and implementation of plant diversification in landscapes, this framework makes it possible to analyse the synergies and antagonisms between different modes of diversification and the conditions of their deployment. Exploring this framework is a prerequisite to the identification of opportunities and key feed-back loops for designing diversification strategies that unlock the agro-ecological potential of future production systems. We conclude that there is a need for interdisciplinary research in experimental landscapes involving farmers and other local stakeholders to design sustainable future agricultural landscapes that deliver high levels of biological control services. [ABSTRACT FROM AUTHOR]

Background: Pulmonary expression of heme oxygenase has been observed in multiple studies. This expression has been found beneficial in decreasing the severity of acute lung injury (ALI) post ischemia–reperfusion (I/R). The aim of this study was to assess the role of exogenous administration of the end-products of heme oxygenase reaction, carbon monoxide, and bilirubin, in the severity of ALI. Study design: We compared five groups of rats (n = 7/group) including a sham group and four I/R of the lower extremities by clamping the abdominal aorta for 2 h followed by reperfusion for 2 h. The four I/R groups included a control group, one pretreated with bilirubin (50 μmol/kg IV), another with inhaled carbon monoxide (CO) (250 ppm), and the last pretreated with both. The severity of ALI has been evaluated by a histological assay grading neutrophilic infiltration, as well as a study of the microvascular permeability using the Evans blue. Results: The administration of CO prevented pulmonary microvascular permeability alteration noted after I/R of the lower limbs (pulmonary content of Evans blue: 141 ± 23 μg/g of tissue in the isolated I/R group versus 68 ± 34 μg/g of tissue in CO group; P < 0.001). Histologically CO administration inhibited neutrophilic sequestration observed after I/R. On the other hand, treatment by bilirubin alone (50 μmol/kg IV) did not modify the extent of pulmonary injury. Conclusion: Exogenous administration of carbon monoxide by inhalation at low doses prevented ALI post-I/R in this model. [Copyright &y& Elsevier]

Background: Expression of inducible heme-oxygenase (HO-1) has been shown to be increased in various inflammatory disorders, which may confer a protective role. The aim of our study was to assess pulmonary expression of HO-1 after ischemia/reperfusion (I/R) of the lower limbs in rats. Materials and methods: We compared three groups of rats (n = 5/group): one Sham group, and two I/R groups (aorta cross-clamped for 2 h followed by 2 h of reperfusion), one of which pre-treated with Zn-protoporphyrin (Zn-PP), a competitive inhibitor of HO (50 μmol/kg, i.p.). At the end of experiment, lungs were harvested for determination of HO activity and HO-1 expression by Western blot and immunohistochemistry. Lung injury was assessed by bronchoalveolar lavage, histological study, and determination of the lung Evans Blue dye content, an index of microvascular permeability. Results: I/R of the lower limbs was responsible for acute lung injury (ALI), characterized by neutrophilic infiltration (87 ± 20 × 103 neutrophils/mm3, Sham group versus 191 ± 38 × 103 neutrophils/mm3, I/R group; P < 0.002) and an increase in lung Evans blue dye content: (74 ± 6 μg/g, Sham group versus 122 ± 48 μg/g, I/R group; P < 0.05). Pre-treatment with Zn-PP further increases the Evans Blue content (122 ± 48 μg/g, I/R group versus 179 ± 23 μg/g Zn-PP group P < 0.05) and the neutrophilic infiltration. Pulmonary heme-oxygenase activity, and HO-1 content were increased after I/R. (10.5 ± 12 pmol bilirubin/mg protein/h, Sham group versus 101.2 ± 66 pmol bilirubin/mg protein/h, I/R group; P < 0.02). Immunohistochemistry revealed that the expression of HO-1 was mainly localized to inflammatory cells. Conclusions: ALI following I/R of the lower limbs in rats is associated with an increase of pulmonary expression of HO-1, inhibition of this expression increase the severity of ALI. [Copyright &y& Elsevier]