Wounding of Arabidopsis halleri leaves enhances cadmium accumulation that acts as a defense against herbivory.

Approximately 0.2 % of all angiosperms are classified as metal hyperaccumulators based on their extraordinarily high leaf metal contents, for example >1 % zinc, >0.1 % nickel or >0.01 % cadmium (Cd) in dry biomass. So far, metal hyperaccumulation has been considered to be a taxon-wide, constitutively expressed trait, the extent of which depends solely on available metal concentrations in the soil. Here we show that in the facultative metallophyte Arabidopsis halleri, both insect herbivory and mechanical wounding of leaves trigger an increase specifically in leaf Cd accumulation. Moreover, the Cd concentrations accumulated in leaves can serve as an elemental defense against herbivory by larvae of the Brassicaceae specialist small white (Pieris rapae), thus allowing the plant to take advantage of this non-essential trace element and toxin. Metal homeostasis genes are overrepresented in the systemic transcriptional response of roots to the wounding of leaves in A. halleri, supporting that leaf Cd accumulation is preceded by systemic signaling events. A similar, but quantitatively less pronounced transcriptional response was observed in A. thaliana, suggesting that the systemically regulated modulation of metal homeostasis in response to leaf wounding also occurs in non-hyperaccumulator plants. This is the first report of an environmental stimulus influencing metal hyperaccumulation.

Responsiveness et changement thérapeutique au travers de l'études de cas

Le concept de responsiveness ou « responsivité » a été proposé dans le domaine de la recherche en psychothérapie pour décrire l'influence mutuelle qui s'exerce continuellement entre patient et thérapeute. La nature responsive des psychothérapies pose alors un problème majeur aux chercheurs, qui adoptent généralement des plans de recherche impliquant des liens de cause à effet et sont en échec dans leur entreprise de mieux comprendre le changement thérapeutique. L'objectif de notre travail est de proposer des pistes pour répondre à ce problème. Nous avons adopté la méthode d'étude de cas, qui permet une analyse en profondeur et en contexte des processus de changement. Dans les deux premières phases de la recherche, nous nous situions dans une approche spécifique à la recherche qualitative en psychothérapie. Nous avons tout d'abord analysé comment le changement s'effectuait chez le patient, en identifiant pas à pas le niveau d'assimilation de ses expériences problématiques. Nous avons ensuite tenté d'appréhender le rôle du thérapeute dans le processus de changement. Notre objectif était d'analyser comment la responsivité du thérapeute pouvait faciliter le processus de changement chez le patient à chaque instant de la thérapie. En suivant une procédure inspirée de l'analyse de la tâche, nous avons identifié pour chaque niveau d'assimilation des interventions thérapeutiques suivies de progression, et élaboré un modèle empirique séquentiel. Dans la troisième phase de la recherche, nous avons effectué un tournant dans notre parcours et sommes allée du côté des sciences du langage. En adoptant une approche dialogique du discours, notre objectif était d'éclairer notre objet d'étude à partir d'une nouvelle perspective et d'ouvrir la réflexion. Nous avons ainsi pu répondre à certaines limites rencontrées dans les premières phases de la recherche, et faire émerger de nouvelles questions et perspectives pour l'étude des processus de changement dans une dimension interactive. -- The concept of responsiveness was developed in psychotherapy research to describe the mutual and constant influence between patient and therapist. The responsive nature of psychotherapy is a serious problem for researchers, who generally adopt research designs involving cause-effect reasoning and fail to better understand therapeutic change. The purpose of our work is to propose some viable possibilities to respond to this problem. We chose the case study method, which enables an analysis in depth and in context of change processes. In the two first phases of research, our approach was specific to qualitative psychotherapy research. We first analyzed how change occurred in the patient, by identifying moment-by-moment the level of assimilation of his or her problematic experiences. We then tried to apprehend the therapist role in the change process. Our aim was to analyze how the therapist responsiveness could facilitate the patient change process at any moment of psychotherapy. We followed a procedure inspired by task analysis and, for each level of assimilation, we identified therapist interventions followed by progression, and elaborated an empirical sequential model. The third phase of research was a turning point, as we went in the field of linguistics. We adopted a dialogical approach of discourse to open up reflection. Thus, we could answer some limitations encountered in the first phases of research, and new questions and perspectives to study change process taking into account the interactive dimension emerged.

The conditions for the reproduction of the SAGUAPAC water cooperative in the city of Santa Cruz de la Sierra, Bolivia : discourse analysis

The SAGUAPAC cooperative in the city of Santa Cruz de la Sierra (Eastern Bolivia) is regularly presented as an example of cooperative successes regarding water supply and sanitation. Its efficiency, both economic and technical, is widely considered as the main reason for its attractiveness. However, without denying its importance, we show, through a discourse analysis from and about SAGUAPAC in local media, that moral and non-instrumental factors are crucial in the reproduction of the cooperative. These factors create attachment and affection toward the cooperative, through a storytelling using a four-dimensional rhetoric (mythification, identification, emotionalisation and personification). This storytelling technique, internalized in the local media discourse and materializing the so-called new spirit of capitalism, exploits the affects and instrumentalisation of local myths and legends, as well as the 'camba' ethnic identity. In that, it tends to retain SAGUAPAC members and to canvass new ones, by providing them with recognition in their quality of local community members. However, the mobilisation of social norms and power hierarchies might end up reinforcing the social exclusion of Andean non-camba immigrants, inspite of an a priori inclusive and democratic organisation.

Clinical determinants of early parasitological response to ACTs in African patients with uncomplicated falciparum malaria: a literature review and meta-analysis of individual patient data.

BACKGROUND: Artemisinin-resistant Plasmodium falciparum has emerged in the Greater Mekong sub-region and poses a major global public health threat. Slow parasite clearance is a key clinical manifestation of reduced susceptibility to artemisinin. This study was designed to establish the baseline values for clearance in patients from Sub-Saharan African countries with uncomplicated malaria treated with artemisinin-based combination therapies (ACTs). METHODS: A literature review in PubMed was conducted in March 2013 to identify all prospective clinical trials (uncontrolled trials, controlled trials and randomized controlled trials), including ACTs conducted in Sub-Saharan Africa, between 1960 and 2012. Individual patient data from these studies were shared with the WorldWide Antimalarial Resistance Network (WWARN) and pooled using an a priori statistical analytical plan. Factors affecting early parasitological response were investigated using logistic regression with study sites fitted as a random effect. The risk of bias in included studies was evaluated based on study design, methodology and missing data. RESULTS: In total, 29,493 patients from 84 clinical trials were included in the analysis, treated with artemether-lumefantrine (n = 13,664), artesunate-amodiaquine (n = 11,337) and dihydroartemisinin-piperaquine (n = 4,492). The overall parasite clearance rate was rapid. The parasite positivity rate (PPR) decreased from 59.7 % (95 % CI: 54.5-64.9) on day 1 to 6.7 % (95 % CI: 4.8-8.7) on day 2 and 0.9 % (95 % CI: 0.5-1.2) on day 3. The 95th percentile of observed day 3 PPR was 5.3 %. Independent risk factors predictive of day 3 positivity were: high baseline parasitaemia (adjusted odds ratio (AOR) = 1.16 (95 % CI: 1.08-1.25); per 2-fold increase in parasite density, P <0.001); fever (>37.5 °C) (AOR = 1.50 (95 % CI: 1.06-2.13), P = 0.022); severe anaemia (AOR = 2.04 (95 % CI: 1.21-3.44), P = 0.008); areas of low/moderate transmission setting (AOR = 2.71 (95 % CI: 1.38-5.36), P = 0.004); and treatment with the loose formulation of artesunate-amodiaquine (AOR = 2.27 (95 % CI: 1.14-4.51), P = 0.020, compared to dihydroartemisinin-piperaquine). CONCLUSIONS: The three ACTs assessed in this analysis continue to achieve rapid early parasitological clearance across the sites assessed in Sub-Saharan Africa. A threshold of 5 % day 3 parasite positivity from a minimum sample size of 50 patients provides a more sensitive benchmark in Sub-Saharan Africa compared to the current recommended threshold of 10 % to trigger further investigation of artemisinin susceptibility.

Nuclear Factor I-C acts as a regulator of hepatocyte proliferation at the onset of liver regeneration.

BACKGROUND & AIMS: Knockout studies of the murine Nuclear Factor I-C (NFI-C) transcription factor revealed abnormal skin wound healing and growth of its appendages, suggesting a role in controlling cell proliferation in adult regenerative processes. Liver regeneration following partial hepatectomy (PH) is a well-established regenerative model whereby changes elicited in hepatocytes lead to their rapid and phased proliferation. Although NFI-C is highly expressed in the liver, no hepatic function was yet established for this transcription factor. This study aimed to determine whether NFI-C may play a role in hepatocyte proliferation and liver regeneration. METHODS: Liver regeneration and cell proliferation pathways following two-thirds PH were investigated in NFI-C knockout (ko) and wild-type (wt) mice. RESULTS: We show that the absence of NFI-C impaired hepatocyte proliferation because of plasminogen activator I (PAI-1) overexpression and the subsequent suppression of urokinase plasminogen activator (uPA) activity and hepatocyte growth factor (HGF) signalling, a potent hepatocyte mitogen. This indicated that NFI-C first acts to promote hepatocyte proliferation at the onset of liver regeneration in wt mice. The subsequent transient down regulation of NFI-C, as can be explained by a self-regulatory feedback loop with transforming growth factor beta 1 (TGF-ß1), may limit the number of hepatocytes entering the first wave of cell division and/or prevent late initiations of mitosis. CONCLUSION: NFI-C acts as a regulator of the phased hepatocyte proliferation during liver regeneration.

An interactive web-GIS tool for risk analysis: a case study in the Fella River basin, Italy

This paper presents a prototype of an interactive web-GIS tool for risk analysis of natural hazards, in particular for floods and landslides, based on open-source geospatial software and technologies. The aim of the presented tool is to assist the experts (risk managers) in analysing the impacts and consequences of a certain hazard event in a considered region, providing an essential input to the decision-making process in the selection of risk management strategies by responsible authorities and decision makers. This tool is based on the Boundless (OpenGeo Suite) framework and its client-side environment for prototype development, and it is one of the main modules of a web-based collaborative decision support platform in risk management. Within this platform, the users can import necessary maps and information to analyse areas at risk. Based on provided information and parameters, loss scenarios (amount of damages and number of fatalities) of a hazard event are generated on the fly and visualized interactively within the web-GIS interface of the platform. The annualized risk is calculated based on the combination of resultant loss scenarios with different return periods of the hazard event. The application of this developed prototype is demonstrated using a regional data set from one of the case study sites, Fella River of northeastern Italy, of the Marie Curie ITN CHANGES project.

The Drosophila TNF Eiger Is an Adipokine that Acts on Insulin-Producing Cells to Mediate Nutrient Response.

Adaptation of organisms to ever-changing nutritional environments relies on sensor tissues and systemic signals. Identification of these signals would help understand the physiological crosstalk between organs contributing to growth and metabolic homeostasis. Here we show that Eiger, the Drosophila TNF-α, is a metabolic hormone that mediates nutrient response by remotely acting on insulin-producing cells (IPCs). In the condition of nutrient shortage, a metalloprotease of the TNF-α converting enzyme (TACE) family is active in fat body (adipose-like) cells, allowing the cleavage and release of adipose Eiger in the hemolymph. In the brain IPCs, Eiger activates its receptor Grindelwald, leading to JNK-dependent inhibition of insulin production. Therefore, we have identified a humoral connexion between the fat body and the brain insulin-producing cells relying on TNF-α that mediates adaptive response to nutrient deprivation.