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31.
32.
Justine D. Ceusters Ange A. Mouithys-Mickalad Thierry J. Franck Sandrine Derochette Alain Vanderplasschen Ginette P. Deby-Dupont Didier A. Serteyn 《Mitochondrion》2013,13(5):410-416
Horses are particularly sensitive to excessive inflammatory reaction where myeloperoxidase, a marker of inflammation, may contribute to mitochondrial dysfunctions. This study investigated the interaction between myeloperoxidase and cultured primary equine skeletal myoblasts, particularly its effect on mitochondrial respiration combined or not with anoxia followed by reoxygenation (AR). We showed that active myeloperoxidase entered into the cells, interacted with mitochondria and decreased routine and maximal respirations. When combined with AR, myeloperoxidase caused a further decrease of these respiratory parameters while the leak increased. Our results indicate that myeloperoxidase amplifies the mitochondrial damages initiated by AR phenomenon and alters the mitochondrial function. 相似文献
33.
Kinsley Narainsamy Corinne Cassier-Chauvat Christophe Junot Franck Chauvat 《Metabolomics : Official journal of the Metabolomic Society》2013,9(1):21-32
Cyanobacteria are environmentally important photosynthetic microorganisms attracting a growing attention in various areas of basic and applied researches. To better understand their metabolism, we presently report on the development of a robust and simple protocol for facile extraction and high throughput analysis of the metabolites of the widely-used strain Synechocystis PCC6803 through liquid chromatography coupled to high resolution mass spectrometry (LC/MS). Our analytical method was developed and tested with 102 reference compounds representative of the chemical diversity of polar cell metabolites, and Synechocystis cell extracts spiked with 37 reference compounds. These samples were analyzed with two chromatographic systems, each coupled to a LTQ-Orbitrap mass spectrometer: a liquid chromatographic system equipped with a pentafluorophenylpropyl column (the PFPP-LC/MS system), and an ultra-high performance liquid chromatographic system with a C18-reversed phase column (the C18-UHPLC/MS system). We showed that the PFPP-LC/MS method performs better than the C18-UHPLC/MS method in terms of retention, separation and detection of metabolites. Consequently, we applied the PFPP-LC/MS method to analyze the metabolome of Synechocystis growing under various conditions of light and glucose, which strongly influence cell growth. We found that glucose increases glucose storage (synthesis of glycogen-like polysaccharide) and catabolism (oxidative pentose phosphate pathway and glycolysis), while it decreases the Calvin–Benson cycle that consumes photosynthetic electrons for CO2 assimilation. Depending on light and glucose availabilities, this global metabolic reprogramming can generate an oxidative stress, likely through the recombination of the glucose-spared electrons with the photosynthetic oxygen thereby producing toxic reactive oxygen species. 相似文献
34.
Franck Desmoulin Michel Galinier Charlotte Trouillet Matthieu Berry Clément Delmas Annie Turkieh Pierre Massabuau Heinrich Taegtmeyer Fatima Smih Philippe Rouet 《PloS one》2013,8(4)
Objective
Mortality in heart failure (AHF) remains high, especially during the first days of hospitalization. New prognostic biomarkers may help to optimize treatment. The aim of the study was to determine metabolites that have a high prognostic value.Methods
We conducted a prospective study on a training cohort of AHF patients (n = 126) admitted in the cardiac intensive care unit and assessed survival at 30 days. Venous plasmas collected at admission were used for 1H NMR – based metabonomics analysis. Differences between plasma metabolite profiles allow determination of discriminating metabolites. A cohort of AHF patients was subsequently constituted (n = 74) to validate the findings.Results
Lactate and cholesterol were the major discriminating metabolites predicting 30-day mortality. Mortality was increased in patients with high lactate and low total cholesterol concentrations at admission. Accuracies of lactate, cholesterol concentration and lactate to cholesterol (Lact/Chol) ratio to predict 30-day mortality were evaluated using ROC analysis. The Lact/Chol ratio provided the best accuracy with an AUC of 0.82 (P < 0.0001). The acute physiology and chronic health evaluation (APACHE) II scoring system provided an AUC of 0.76 for predicting 30-day mortality. APACHE II score, Cardiogenic shock (CS) state and Lact/Chol ratio ≥ 0.4 (cutoff value with 82% sensitivity and 64% specificity) were significant independent predictors of 30-day mortality with hazard ratios (HR) of 1.11, 4.77 and 3.59, respectively. In CS patients, the HR of 30-day mortality risk for plasma Lact/Chol ratio ≥ 0.4 was 3.26 compared to a Lact/Chol ratio of < 0.4 (P = 0.018). The predictive power of the Lact/Chol ratio for 30-day mortality outcome was confirmed with the independent validation cohort.Conclusion
This study identifies the plasma Lact/Chol ratio as a useful objective and simple parameter to evaluate short term prognostic and could be integrated into quantitative guidance for decision making in heart failure care. 相似文献35.
Oula Shahin Nicolas Martin-St Paul Serge Rambal Richard Joffre Franck Richard 《Symbiosis (Philadelphia, Pa.)》2013,61(1):1-12
Understanding the factors underlying the distribution of biodiversity is a challenging issue in ecology. Here, we examined the distribution patterns of ectomycorrhizal fungal diversity across the soil profile in three Quercus ilex forests. Contact exploration type strongly dominated at all sites, but was most prevalent in the upper, organic-rich soil layers. At each site, three quarters of the ectomycorrhizal tips and 59 % of taxa were restricted to the ten first centimeters of the soil profile. The relative abundance of the dominant family Russulaceae increased with increasing soil depth. Species composition varied significantly among sites, with most species being rare. Species that occurred in only one of the three sites accounted for 78.9 % of all species, and 57.3 % of species were represented by a single ECM root tip. Our results suggest that (i) rare species at both local and regional scales contribute to the highly diverse fungal assemblages in Mediterranean forests and (ii) multi-sites studies including the whole soil profile are needed to provide comprehensive overviews of the taxonomic and functional diversities of ectomycorrhizal communities. 相似文献
36.
Maud Martin Ilse Geudens Jonathan Bruyr Michael Potente Anouk Bleuart Marielle Lebrun Nicolas Simonis Christophe Deroanne Jean‐Claude Twizere Philippe Soubeyran Paul Peixoto Denis Mottet Veerle Janssens Wolf‐Karsten Hofmann Filip Claes Peter Carmeliet Richard Kettmann Holger Gerhardt Franck Dequiedt 《The EMBO journal》2013,32(18):2491-2503
37.
Eric Allan Wolfgang W. Weisser Markus Fischer Ernst-Detlef Schulze Alexandra Weigelt Christiane Roscher Jussi Baade Romain L. Barnard Holger Beßler Nina Buchmann Anne Ebeling Nico Eisenhauer Christof Engels Alexander J. F. Fergus Gerd Gleixner Marlén Gubsch Stefan Halle Alexandra M. Klein Ilona Kertscher Annely Kuu Markus Lange Xavier Le Roux Sebastian T. Meyer Varvara D. Migunova Alexandru Milcu Pascal A. Niklaus Yvonne Oelmann Esther Pašalić Jana S. Petermann Franck Poly Tanja Rottstock Alexander C. W. Sabais Christoph Scherber Michael Scherer-Lorenzen Stefan Scheu Sibylle Steinbeiss Guido Schwichtenberg Vicky Temperton Teja Tscharntke Winfried Voigt Wolfgang Wilcke Christian Wirth Bernhard Schmid 《Oecologia》2013,173(1):223-237
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination. 相似文献
38.
Emilie Widemann Laurence Miesch Rapha?l Lugan Emilie Holder Clément Heinrich Yann Aubert Michel Miesch Franck Pinot Thierry Heitz 《The Journal of biological chemistry》2013,288(44):31701-31714
Jasmonates (JAs) are a class of signaling compounds that mediate complex developmental and adaptative responses in plants. JAs derive from jasmonic acid (JA) through various enzymatic modifications, including conjugation to amino acids or oxidation, yielding an array of derivatives. The main hormonal signal, jasmonoyl-l-isoleucine (JA-Ile), has been found recently to undergo catabolic inactivation by cytochrome P450-mediated oxidation. We characterize here two amidohydrolases, IAR3 and ILL6, that define a second pathway for JA-Ile turnover during the wound response in Arabidopsis leaves. Biochemical and genetic evidence indicates that these two enzymes cleave the JA-Ile signal, but act also on the 12OH-JA-Ile conjugate. We also show that unexpectedly, the abundant accumulation of tuberonic acid (12OH-JA) after wounding originates partly through a sequential pathway involving (i) conjugation of JA to Ile, (ii) oxidation of the JA-Ile conjugate, and (iii) cleavage under the action of the amidohydrolases. The coordinated actions of oxidative and hydrolytic branches in the jasmonate pathway highlight novel mechanisms of JA-Ile hormone turnover and redefine the dynamic metabolic grid of jasmonate conversion in the wound response. 相似文献
39.
40.
Ahmed Abdelmoniem Mousa Shinuo Cao Gabriel Oluga Aboge Mohamad Alaa Terkawi Ahmed El Kirdasy Akram Salama Mabrouk Attia Mahmoud Aboulaila Mo Zhou Ketsarin Kamyingkird Paul Franck Adjou Moumouni Tatsunori Masatani Sami Ahmed Abd El Aziz Waheed Mohammed Moussa Bayin Chahan Shinya Fukumoto Yoshifumi Nishikawa Salah Sayed El Ballal Xuenan Xuan 《Experimental parasitology》2013
Identification and molecular characterization of Babesia gibsoni proteins with potential antigenic properties are crucial for the development and validation of the serodiagnostic method. In this study, we isolated a cDNA clone encoding a novel B. gibsoni 76-kDa protein by immunoscreening of the parasite cDNA library. Computer analysis revealed that the protein presents a glutamic acid-rich region in the C-terminal. Therefore, the protein was designated as B. gibsoni glutamic acid-rich protein (BgGARP). A BLASTp analysis of a translated BgGARP polypeptide demonstrated that the peptide shared a significant homology with a 200-kDa protein of Babesia bigemina and Babesia bovis. A truncated BgGARP cDNA (BgGARPt) encoding a predicted 13-kDa peptide was expressed in Escherichia coli (E. coli), and mouse antisera against the recombinant protein were used to characterize a corresponding native protein. The antiserum against recombinant BgGARPt (rBgGARPt) recognized a 140-kDa protein in the lysate of infected erythrocytes, which was detectable in the cytoplasm of the parasites by confocal microscopic observation. In addition, the specificity and sensitivity of enzyme-linked immunosorbent assay (ELISA) with rBgGARPt were evaluated using B. gibsoni-infected dog sera and specific pathogen-free (SPF) dog sera. Moreover, 107 serum samples from dogs clinically diagnosed with babesiosis were examined using ELISA with rBgGARPt. The results showed that 86 (80.4%) samples were positive by rBgGARPt-ELISA, which was comparable to IFAT and PCR as reference test. Taken together, these results demonstrate that BgGARP is a suitable serodiagnostic antigen for detecting antibodies against B. gibsoni in dogs. 相似文献