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Orsay, France

Alric J.,University Pierre and Marie Curie | Lavergne J.,DSV | Rappaport F.,University Pierre and Marie Curie
Biochimica et Biophysica Acta - Bioenergetics | Year: 2010

Assimilation of atmospheric CO2 by photosynthetic organisms such as plants, cyanobacteria and green algae, requires the production of ATP and NADPH in a ratio of 3:2. The oxygenic photosynthetic chain can function following two different modes: the linear electron flow which produces reducing power and ATP, and the cyclic electron flow which only produces ATP. Some regulation between the linear and cyclic flows is required for adjusting the stoichiometric production of high-energy bonds and reducing power. Here we explore, in the green alga Chlamydomonas reinhardtii, the onset of the cyclic electron flow during a continuous illumination under aerobic conditions. In mutants devoid of Rubisco or ATPase, where the reducing power cannot be used for carbon fixation, we observed a stimulation of the cyclic electron flow. The present data show that the cyclic electron flow can operate under aerobic conditions and support a simple competition model where the excess reducing power is recycled to match the demand for ATP. © 2009 Elsevier B.V. All rights reserved. Source

Popa M.,Decembrie University | Glevitzky M.,DSV | Popa D.,Decembrie University | Varvara S.,Decembrie University | Dumitrel G.-A.,Polytechnic University of Timisoara
Journal of Environmental Protection and Ecology | Year: 2012

This paper aims to determine the soil pollution with heavy metals near the river Ampoi. Study results will further reveal the sources of river pollution and the pressing need for strategic rehabilitation of the Ampoi valley basin given the fact that in the area the industry specialised in copper metallurgy SC 'Ampelum' S.A. Zlatna has not been functioning since 2004. Source

Dorothee G.,French Institute of Health and Medical Research | Dorothee G.,University Pierre and Marie Curie | Bottlaender M.,DSV | Moukari E.,French Institute of Health and Medical Research | And 19 more authors.
Archives of Neurology | Year: 2012

Objective: To compare serum antiamyloid-β (Aβ) antibodies in typical and atypical Alzheimer disease (AD). Design: Preliminary observations. Subjects: Thirteen patients with AD, 8 patients with posterior cortical atrophy with evidence of AD (PCA-AD) pathophysiological process by both cerebrospinal fluid (CSF) biomarkers and amyloid imaging, and 12 age-matched control individuals. Interventions: The class and subclass levels of serum anti-Aβ antibodies were measured using an oligomer-based enzyme-linked immunosorbent assay. This method allowed measuring both free antibodies and, after acidic treatment, the total fraction that includes all antibodies complexed with circulating Aβ40/42 and any cross-reacting antigen. Results: Anti-Aβ IgG were restricted to the IgG1 and IgG3 subclasses. Their total levels were strikingly lower and more homogeneous in patients with PCA compared with both typical AD and controls, while biomarkers of amyloid deposition (CSF Aβ42 and positron emission tomography amyloid imaging) were similar in patients with AD and patients with PCA. Conclusions: Serum anti-Aβ IgG1 and IgG3 antibodies differ between distinct forms of AD. Its significance is discussed for possible implications as immune effectors in the specific pathophysiology of AD variants. ©2012 American Medical Association. All rights reserved. Source

Sotomane C.,DSV | Asker L.,DSV | Massingue V.,MCT
2011 IST-Africa Conference Proceedings, IST 2011 | Year: 2011

Accurate short term load forecasting is crucial for efficient operations planning of electrical power systems. We present a model for automatic forecasting of the short term (24 hours) electrical power consumption in Maputo, Mozambique. The proposed model is based on analysis of historical records of power consumption combined with information about additional factors that influence the consumption. The data is clustered into segments with the objective of identifying similar consumption patterns. These consumption patterns are then correlated with weather conditions and used to construct an automated prediction model for load forecasting. Today these forecasts are made manually by experts at Electricidade de Moçambique (the local power company) using conventional methods. The automated prediction model that was developed in this project presents an accurate and consistent complement to manual prediction and is currently being evaluated for the possibility of augmenting the manual forecasts with additional information. © 2011 IIMC LTD. Source

Christie-Oleza J.A.,DSV | Miotello G.,DSV | Armengaud J.,DSV
Journal of Proteome Research | Year: 2013

Whole-cell, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry has become a routine and reliable method for microbial characterization due to its simplicity, low cost, and high reproducibility. The identification of microbial isolates relies on the spectral resemblance of low-molecular-weight proteins to already-existing isolates within the databases. This is a gold standard for clinicians who have a finite number of well-defined pathogenic strains but represents a problem for environmental microbiologists with an overwhelming number of organisms to be defined. Here we set a milestone for implementing whole-cell MALDI-TOF mass spectrometry to identify isolates from the biosphere. To make this technique accessible for environmental studies, we propose to (i) define biomarkers that will always show up with an intense m/z signal in the MALDI-TOF spectra and (ii) create a database with all the possible m/z values that these biomarkers can generate to screen new isolates. We tested our method with the relevant marine Roseobacter lineage. The use of shotgun nanoLC-MS/MS proteomics on the small proteome fraction of nine Roseobacter strains and the proteogenomic toolbox helped us to identify potential biomarkers in terms of protein abundance and low variability among strains. We show that the DNA binding protein, HU, and the ribosomal proteins, L29 and L30, are the most robust biomarkers within the Roseobacter clade. The molecular weights of these three biomarkers, as for other conserved homologous proteins, vary due to sequence variation above the genus level. Therefore, we calculated the m/z values expected for each one of the known Roseobacter genera and tested our strategy during an extensive screening of natural marine isolates obtained from coastal waters of the Western Mediterranean Sea. The use of this technique versus standard sequencing methods is discussed. © 2013 American Chemical Society. Source

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