57 results on '"Guichard N"'
Search Results
2. Characteristics of the multi-resistant bacteria that actually diffuse in the Centre region, France, in and out of healthcare institutions: O132
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van der Mee-Marquet, N., Valentin-Domelier, A. S., Charbonnier, T., Gras, M., Ligeon, L. A., Guichard, N., Girard, N., and Quentin, R.
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- 2010
3. Defence mechanism: the ageing process and seasonal change can have a serious effect on the skin's barrier function. M Jouandeaud, L Moreau, C Chauprade, N Guichard, B Closs and V Gloaguen discuss the use of rhamnogalacturonans as a new therapeutic strategy
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Jouandeaud, M., Moreau, L., Chauprade, C., Guichard, N., Closs, B., and Gloaguen, V.
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Cholesterol ,Business ,Business, international ,Fashion, accessories and textiles industries ,Pharmaceuticals and cosmetics industries - Published
- 2004
4. Defence mechanism
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Jouandeaud, M., Moreau, L., Chauprade, C., Guichard, N., and Closs, B.
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Toiletries industry -- Research ,Chestnut -- Usage ,Chestnut -- Research ,Skin -- Research ,Skin -- Care and treatment ,Business ,Business, international ,Pharmaceuticals and cosmetics industries - Published
- 2004
5. DI-004 BUSULFAN stability determination by UHPLC-MS
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Guichard, N, primary, Bonnabry, P, additional, Rudaz, S, additional, and Fleury-Souverain, S, additional
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- 2017
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6. Using a powerful computer for acquiring and processing chromatographic and other analytical data
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Guichard, N. and Sicard, G.
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- 1972
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7. Biochemical characterization of the soluble organic matrix of gastroliths from decapods
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Luquet, G., Fernández, M. S., Navarrete, M. J., Arias, J. L., Guichard, N., Marie, B., and Marin, F.
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Gastroliths are disc-shaped calcium storage structures cyclically elaborated by some decapods in their stomach wall. In the present study, we extracted the gastrolith organic matrix from three different decapods, two crayfishes and one lobster, and began to characterize the soluble matrix obtained after decalcification by acetic acid. By using different staining (silver nitrate, Coomassie Blue, Stains-all) after SDS-PAGE, we evidenced that these soluble fractions are rich in polypeptides, some seems common, others are completely different. Among them, putative calcium binding proteins might be present and have to be further characterized. This soluble organic matrix also interacts in vitro with calcite crystals growth, suggesting its involvement in the calcium carbonate precipitation. The main conclusion of this preliminary study is that close species from the same order of animals have developed very similar calcium storage strategies by elaborating morphologically identical structures, but different in their molecular composition.
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- 2007
8. Long Distance Seed Dispersal by Forest Elephants
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John R. Poulsen, Christopher Beirne, Colin Rundel, Melissa Baldino, Seokmin Kim, Julia Knorr, Taylor Minich, Lingrong Jin, Chase L. Núñez, Shuyun Xiao, Walter Mbamy, Guichard Ndzeng Obiang, Juliana Masseloux, Tanguy Nkoghe, Médard Obiang Ebanega, Connie J. Clark, Michael J. Fay, Pete Morkel, Joseph Okouyi, Lee J. T. White, and Justin P. Wright
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seed dispersal ,elephant ,tropical forest ,animal movement ,central Africa ,gut passage time ,Evolution ,QH359-425 ,Ecology ,QH540-549.5 - Abstract
By dispersing seeds long distances, large, fruit-eating animals influence plant population spread and community dynamics. After fruit consumption, animal gut passage time and movement determine seed dispersal patterns and distances. These, in turn, are influenced by extrinsic, environmental variables and intrinsic, individual-level variables. We simulated seed dispersal by forest elephants (Loxodonta cyclotis) by integrating gut passage data from wild elephants with movement data from 96 individuals. On average, elephants dispersed seeds 5.3 km, with 89% of seeds dispersed farther than 1 km. The longest simulated seed dispersal distance was 101 km, with an average maximum dispersal distance of 40.1 km. Seed dispersal distances varied among national parks, perhaps due to unmeasured environmental differences such as habitat heterogeneity and configuration, but not with human disturbance or habitat openness. On average, male elephants dispersed seeds farther than females. Elephant behavioral traits strongly influenced dispersal distances, with bold, exploratory elephants dispersing seeds 1.1 km farther than shy, idler elephants. Protection of forest elephants, particularly males and highly mobile, exploratory individuals, is critical to maintaining long distance seed dispersal services that shape plant communities and tropical forest habitat.
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- 2021
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9. Les enfants et la Publicité
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UCL - SSH/ILSM - Louvain School of Management Research Institute, Guichard, N., Pecheux, Claude, UCL - SSH/ILSM - Louvain School of Management Research Institute, Guichard, N., and Pecheux, Claude
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Ce chapitre présente un état de l'art de la recherche sur l'Enfant et la Publicité.
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- 2012
10. P.1.i.004 Neu-P11: a novel drug for the treatment of insomnia and central sensitivity syndrome symptoms – results of a Phase-Ib study
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Katz, A., primary, Metzger, D., additional, Staner, L., additional, Pross, N., additional, Cornette, F., additional, Guichard, N., additional, Laudon, M., additional, Nir, T., additional, and Zisapel, N., additional
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- 2012
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11. Des tonnes de tomes dans quelques pages de revue: six ans de bibliographie dans RAM
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Dorey, F., Gregory, P., Guichard, N., Bouladi, Emna, ESC Rouen, and Université de Lille, Sciences et Technologies
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[SHS.GESTION]Humanities and Social Sciences/Business administration ,[SHS.GESTION] Humanities and Social Sciences/Business administration - Abstract
International audience; Depuis six ans, Recherche et Applications en Marketing rend compte des principaux ouvrages de marketing publiés en langue française. Un bilan critique de ce travail, établi autour de trois questions clés: Avons-nous efficacement travaillé? Avons-nous convenablement reflété la réalité? Avons-nous été bien perçus?, permet de prendre la mesure de la richesse de ces publications et de fournir des indications sur les ouvrages de prédilection des membres de l'Association française de Marketing.
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- 1992
12. Régulation directe de l’invasine Rck de Salmonella par le quorum-sensing
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Nadia Abed, Olivier Grépinet, Genaro Hurtado-Escobar, Guichard, N., Agnès Wiedemann, Philippe Velge, Isabelle Virlogeux-Payant, Infectiologie et Santé Publique (UMR ISP), Institut National de la Recherche Agronomique (INRA)-Université de Tours, Société Française de Microbiologie (SFM). FRA., and Institut National de la Recherche Agronomique (INRA)-Université de Tours (UT)
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[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
13. Détermination des naphténes contenus dans des fractions d'essence de pétrole
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Abo-Lemon, F.S., primary and Guichard, N., additional
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- 1974
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14. Robotic sample changers for macromolecular X-ray crystallography and biological small-angle X-ray scattering at the National Synchrotron Light Source II. Corrigendum.
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Lazo EO, Antonelli S, Aishima J, Bernstein HJ, Bhogadi D, Fuchs MR, Guichard N, McSweeney S, Myers S, Qian K, Schneider D, Shea-McCarthy G, Skinner J, Sweet R, Yang L, and Jakoncic J
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A correction in the paper by Lazo et al. [(2021). J. Synchrotron Rad. 28, 1649-1661] is made., (open access.)
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- 2022
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15. Development and Proof of Concept of an Audit Toolkit for the Safe Handling of Cytotoxic Drugs in Low- and Middle-Income Countries.
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von Grünigen S, Falaschi L, Guichard N, Fleury-Souverain S, Geissbühler A, and Bonnabry P
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- Africa, Developing Countries, Health Personnel, Humans, Antineoplastic Agents, Pharmaceutical Preparations
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Purpose: Chemotherapies are considered high-risk drugs for patient and staff safety. Considering the rising burden of cancer and the increasing use of chemotherapy drugs in low- and middle-income countries (LMICs), promoting continuous improvements in the safety and quality of practices in these settings is essential. This paper describes the development and proof of concept of a toolkit to audit chemotherapy handling practices in the health care facilities of LMICs., Methods: A steering committee defined the audit method and the toolkit content. Several checklists were developed to facilitate the audit and data collection. Items included in checklists were derived from key reference works on safe handling. Different tools were validated using Delphi surveys and expert reviews. Audits of pilot sites were performed to test the toolkit's applicability and relevance., Results: The toolkit contains a 134-item global assessment tool for the different processes at each step of the medication pathway and three step-specific observation checklists to assess different health workers' practices during the prescription, preparation, and administration of chemotherapies. The toolkit also proposes using a surface-wipe sampling method to measure any cytotoxic contamination of the immediate environment. The toolkit was tested in three teaching hospitals in Africa., Conclusion: The toolkit developed was successfully implemented in a variety of LMIC settings, providing a comprehensive evaluation of the quality and safety of the chemotherapy drug handling practices in participating health care facilities. This toolkit can help facilities in LMICs to implement a new approach to continuously improving the quality and safety of their practices and ultimately ensure patient and staff safety.
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- 2021
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16. Robotic sample changers for macromolecular X-ray crystallography and biological small-angle X-ray scattering at the National Synchrotron Light Source II.
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Lazo EO, Antonelli S, Aishima J, Bernstein HJ, Bhogadi D, Fuchs MR, Guichard N, McSweeney S, Myers S, Qian K, Schneider D, Shea-McCarthy G, Skinner J, Sweet R, Yang L, and Jakoncic J
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- Equipment Design, Scattering, Small Angle, Software, Synchrotrons, X-Rays, Crystallography, X-Ray methods, Macromolecular Substances chemistry, Robotics methods
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Here we present two robotic sample changers integrated into the experimental stations for the macromolecular crystallography (MX) beamlines AMX and FMX, and the biological small-angle scattering (bioSAXS) beamline LiX. They enable fully automated unattended data collection and remote access to the beamlines. The system designs incorporate high-throughput, versatility, high-capacity, resource sharing and robustness. All systems are centered around a six-axis industrial robotic arm coupled with a force torque sensor and in-house end effectors (grippers). They have the same software architecture and the facility standard EPICS-based BEAST alarm system. The MX system is compatible with SPINE bases and Unipucks. It comprises a liquid nitrogen dewar holding 384 samples (24 Unipucks) and a stay-cold gripper, and utilizes machine vision software to track the sample during operations and to calculate the final mount position on the goniometer. The bioSAXS system has an in-house engineered sample storage unit that can hold up to 360 samples (20 sample holders) which keeps samples at a user-set temperature (277 K to 300 K). The MX systems were deployed in early 2017 and the bioSAXS system in early 2019.
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- 2021
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17. Determination of antiretroviral drugs for buyers' club in Switzerland using capillary electrophoresis methods.
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Guichard N, Tobolkina E, El Morabit L, Bonnabry P, Vernaz N, and Rudaz S
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- Anti-Retroviral Agents therapeutic use, Humans, Pharmaceutical Preparations, Switzerland, Electrophoresis, Capillary, HIV Infections drug therapy, HIV-1
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Human immunodeficiency virus-acquired immunodeficiency syndrome continues to be a major global public health issue, having claimed almost 33 million lives to date. Due to the high cost of antiretroviral treatment, access to these drugs remains difficult for vulnerable populations, such as migrants and people living in prisons, who often do not have health insurance. These factors lead to poorer health outcomes and higher transmission rates. The personal importation scheme for unapproved generics from foreign countries is one option to access affordable human immunodeficiency virus treatment. However, the risk of importing falsified medicine remains high, and the quality control of unapproved drugs is lacking. In this context, three CE methods for the analysis of nine antiviral drugs found in commercial pharmaceutical formulations were evaluated. The selected compounds were emtricitabine, tenofovir disoproxil, tenofovir alafenamide, rilpivirine, efavirenz, raltegravir, dolutegravir, abacavir, and lamivudine. The developed methods were successfully applied to determine the active pharmaceutical ingredients of commercial formulations and unapproved generics. The quality control of unapproved generics by CE is an attractive approach due to its good standard of quality, low cost, ecofriendliness, and ease of implementation., (© 2020 Wiley-VCH GmbH.)
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- 2021
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18. Wipe-sampling procedure optimisation for the determination of 23 antineoplastic drugs used in the hospital pharmacy.
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Guichard N, Boccard J, Rudaz S, Bonnabry P, and Fleury Souverain S
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- Chromatography, Liquid, Ifosfamide analysis, Tandem Mass Spectrometry methods, Antineoplastic Agents analysis, Pharmacy Service, Hospital
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Purpose: Optimise a wipe sampling procedure to evaluate the surface contamination for 23 antineoplastic drugs used in the hospital pharmacy., Methods: The influence of various parameters (ie, sampling device, sampling solution, desorption modes) was evaluated using a validated liquid chromatography-mass spectrometry (LC-MS/MS) method able to quantify 23 antineoplastic drugs widely used in the hospital pharmacy: 5-fluorouracil, busulfan, cyclophosphamide, cytarabine, dacarbazine, daunorubicin, docetaxel, doxorubicin, epirubicin, etoposide, etoposide phosphate, fludarabine phosphate, ganciclovir, gemcitabine, idarubicin, ifosfamide, irinotecan, methotrexate, paclitaxel, pemetrexed, raltitrexed, topotecan and vincristine. Best conditions were tested with real samples from a hospital pharmacy chemotherapy compounding unit., Results: Polyester swabs (TX714 and TX716) gave satisfactory results for the desorption step for all compounds with mean recoveries of 90% and 95%, respectively. For the wiping step, higher recoveries were obtained using TX716 and isopropanol 75% as wiping solution. As anticipated, most intense contaminations were found close to the chemotherapy production site, on surfaces the most frequently in contact with operators' hands., Conclusion: Wipe sampling method was successfully developed and applied to real samples to determine surface contamination with 23 antineoplastic agents in trace amounts., Competing Interests: Competing interests: None declared., (© European Association of Hospital Pharmacists 2021. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2021
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19. Efficiency of four solutions in removing 23 conventional antineoplastic drugs from contaminated surfaces.
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Simon N, Guichard N, Odou P, Decaudin B, Bonnabry P, and Fleury-Souverain S
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- Solutions, Stainless Steel, Surface Properties, Antineoplastic Agents isolation & purification, Decontamination, Drug Contamination
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Background: Residual contamination by intravenous conventional antineoplastic drugs (ICAD) is still a daily issue in hospital facilities. This study aimed to compare the efficiency (EffQ) of 4 different solutions to remove 23 widely used ICADs from surfaces., Method and Findings: A solution containing 23 ICADs (4 alkylating agents, 8 antimetabolites, 2 topo-I inhibitors, 6 topo-II inhibitors and 3 spindle poisons) was spread over 100 cm2 stainless steel. After drying, decontamination was carried out using 10×10 cm wipes moistened with 300 μL of one of the following solutions: 70% isopropanol (S1); ethanol-hydrogen peroxide 91.6-50.0 mg/g (S2); 10-2 M sodium dodecyl sulphate/isopropanol 80/20 (S3) or 0.5% sodium hypochlorite (S4). Six tests were performed for each decontamination solution. Two modalities were tested: a single wipe motion from top to bottom or vigorous wiping (n = 6 for each modality). Residual contamination was measured with a validated liquid chromatography with tandem mass spectrometry detection method. Solution efficiency (in %) was computed as follows: EffQ = 1-(quantity after decontamination/quantity before decontamination), as median (min-max) for the 23 ICADs. The overall decontamination efficiency (EffQ) of the 4 solutions was compared by a Kruskall-Wallis test. Decontamination modalities were compared for each solution and per ICAD with a Mann-Whitney test (p<0.05). EffQ were significantly different from one solution to the next for single wipe motion decontamination: 79.9% (69.3-100), 86.5% (13.0-100), 85.4% (56.5-100) and 100% (52.9-100) for S1, S2, S3 and S4 (p<0.0001), respectively. Differences were also significant for vigorous decontamination: EffQ of 84.3% (66.0-100), 92.3% (68.7-100), 99.6% (84.8-100) and 100% (82.9-100) for S1, S2, S3 and S4, respectively (p<0.0001). Generally, vigorous decontamination increased EffQ for all tested solutions and more significantly for the surfactant., Conclusion: Decontamination efficiency depended on the solution used but also on the application modality. An SDS admixture seems to be a good alternative to sodium hypochlorite, notably after vigorous chemical decontamination with no hazard either to materials or workers., Competing Interests: The authors have read the journal's policy and the authors of this paper have the following competing interests: NS received a grant from AstraZeneca for his post-doctoral position in the University Hospital of Geneva. There are no patents, products in development or marketed products associated with this research to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
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- 2020
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20. Validation and uncertainty estimation for trace amounts determination of 25 drugs used in hospital chemotherapy compounding units.
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Guichard N, Rudaz S, Bonnabry P, and Fleury-Souverain S
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- Chromatography, High Pressure Liquid, Decontamination, Drug Compounding standards, Pharmacy Service, Hospital standards, Sensitivity and Specificity, Tandem Mass Spectrometry, Uncertainty, Antineoplastic Agents analysis, Environmental Pollutants analysis, Hazardous Substances analysis
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The validation and uncertainty assessment of the analytical method developed for the simultaneous determination of 25 anticancer drugs commonly handled in hospital pharmacy was reported. Selected compounds were 5-fluorouracil, cytarabine, fludarabine phosphate, ganciclovir, gemcitabine, dacarbazine, methotrexate, pemetrexed, busulfan, raltitrexed, etoposide phosphate, topotecan, ifosfamide, cyclophosphamide, irinotecan, doxorubicin, epirubicin, daunorubicin, idarubicin, vincristine, vinblastine, vinorelbine, docetaxel and paclitaxel. Accuracy and uncertainty profiles were obtained for all compounds. Quantitative performances were satisfactory in term of specificity, sensitivity, precision and accuracy. Repeatability (1.9-25.4%) and intermediate precision (2.7-29%) were determined for all target compounds. Lower limits of quantification between 1 and 25 ng/mL were obtained. Uncertainty associated to measurement of routine samples was evaluated. The multi-targeted method was specific and reliable and was successfully applied to wipe samples from hospital pharmacy chemotherapy compounding unit and to the determination of outside contamination of vials from pharmaceutical manufacturers., (Copyright © 2019 Elsevier B.V. All rights reserved.)
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- 2019
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21. Computer-assisted UHPLC-MS method development and optimization for the determination of 24 antineoplastic drugs used in hospital pharmacy.
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Guichard N, Fekete S, Guillarme D, Bonnabry P, and Fleury-Souverain S
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- Antineoplastic Agents toxicity, Chromatography, High Pressure Liquid instrumentation, Chromatography, High Pressure Liquid methods, Computer Simulation, Drug Compounding, Software, Tandem Mass Spectrometry instrumentation, Tandem Mass Spectrometry methods, Temperature, Antineoplastic Agents analysis, Chemical Safety methods, Models, Chemical, Pharmacy Service, Hospital methods, Safety Management methods
- Abstract
This study reports the use of retention modeling software for the successful method development of 24 injectable antineoplastic agents. Firstly, a generic screening of several stationary and mobile phases (using various organic modifiers and pH) was achieved. Then, an optimization procedure of mobile phase temperature, gradient profile and mobile phase binary composition was conducted through only 28 real experiments using retention modeling software for data treatment. Finally, the optimized separation was achieved with a mobile phase consisting in 10 mM acetic acid at pH 5.1 (A) and acetonitrile (B). A Waters CORTECS® T3 column (100 × 2.1 mm, 1.6 μm) operated at 25 °C with a gradient time of 17.5 min (0-51%B) at a flow rate of 0.4 mL/min was used. The prediction offered by the retention model was found to be highly reliable, with an average error lower than 1%. A robustness testing step was also assessed from a virtual experimental design. Success rate and regression coefficient were evaluated without the need to perform any real experiment. The developed LC-MS method was successfully applied to the analysis of pharmaceutical formulations and wiping samples from working environment., (Copyright © 2018 Elsevier B.V. All rights reserved.)
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- 2019
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22. Determination of 16 antineoplastic drugs by capillary electrophoresis with UV detection: Applications in quality control.
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Guichard N, Ogereau M, Falaschi L, Rudaz S, Schappler J, Bonnabry P, and Fleury-Souverain S
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- Linear Models, Quality Control, Reproducibility of Results, Sensitivity and Specificity, Antineoplastic Agents analysis, Electrophoresis, Capillary methods, Spectrophotometry, Ultraviolet methods
- Abstract
Two capillary electrophoresis (CE) methods were developed for the analysis of 16 antineoplastic drugs contained in injectable pharmaceutical formulations. A capillary zone electrophoresis (CZE) method coupled to UV was developed with a background electrolyte (BGE) made of a 100 mM phosphate buffer at pH 2.5 containing 50% v/v of acetonitrile and dynamic coating of capillaries with Ceofix®. This method allowed the analysis of doxorubicin, epirubicin, idarubicin, daunorubicin, irinotecan, topotecan, vincristine, vindesine, vinblastine, and vinorelbine in less than 8 min. A micellar electrokinetic chromatography (MEKC) method coupled to UV was also developed for the determination of methotrexate, pemetrexed, etoposide, etoposide phosphate, fludarabine phosphate, and 5-fluorouracil. A run time of 16 min was obtained with a BGE made of 50 mM borate buffer at pH 9.2 with 80 mM of sodium dodecyl sulfate (SDS) and 20% v/v of acetonitrile. For both methods, the applied voltage was 30 kV and the sample injection was performed in the hydrodynamic mode. All analyses were carried out in fused silica capillaries with an internal diameter of 50 μm and a total length of 64.5 cm. Both methods were validated and trueness values between 99.4 and 101.3% were obtained with repeatability and intermediate precision values of 0.5-1.8% for all drugs. These methods were found appropriate for controlling injectable pharmaceutical formulations containing antineoplastic drugs and successfully applied in quality control., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2018
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23. Stability of busulfan solutions in polypropylene syringes and infusion bags as determined with an original assay.
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Guichard N, Bonnabry P, Rudaz S, and Fleury-Souverain S
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- Antineoplastic Agents, Alkylating analysis, Busulfan analysis, Drug Packaging, Drug Stability, Drug Storage, Syringes, Antineoplastic Agents, Alkylating chemistry, Busulfan chemistry, Pharmaceutical Solutions chemistry
- Abstract
Purpose: The stability of busulfan solution in 0.9% sodium chloride and stored in polypropylene syringes or infusion bags was evaluated., Methods: Busulfan solutions (0.54 mg/mL) were prepared and transferred to 50-mL polypropylene syringes and 100- and 500-mL polypropylene infusion bags and stored at 2-8 and 23-27 °C. Chemical stability was measured using a stability-indicating, ultrahigh performance liquid chromatography coupled to mass spectrometry method. The stability of busulfan was assessed by measuring the percentage of the initial concentration remaining at the end of each time point of analysis. The initial busulfan concentration was defined as 100%. Stability was defined as retention of at least 90% of the initial busulfan concentration. A visual inspection of the samples for particulate matter, clarity, and color without instrumentation of magnification was conducted at each time point of analysis., Results: The visual inspection demonstrated no influence of the storage container when busulfan infusions diluted in 0.9% sodium chloride injection were stored at 23-27 °C. No color change or precipitate was observed at this temperature; however, a rapid decrease of the busulfan content in all containers stored at room temperature was observed. Busulfan in syringes was chemically stable for 12 hours, while busulfan in infusion bags (100 and 500 mL) was stable only for 3 hours at 23-27 °C., Conclusion: Busulfan 0.54-mg/mL solution in 0.9% sodium chloride injection was physically and chemically stable for 30 hours when stored in 50-mL polypropylene syringes at 2-8 °C and protected from light., (Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.)
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- 2017
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24. Antineoplastic drugs and their analysis: a state of the art review.
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Guichard N, Guillarme D, Bonnabry P, and Fleury-Souverain S
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- Humans, Quality Control, Antineoplastic Agents pharmacology, Neoplasms drug therapy
- Abstract
The number of patients suffering from cancer is constantly increasing and, consequently, the number of different chemotherapy treatments administered is increasing. Given the high reactivity and toxicity of antineoplastic drugs, analytical methods are required in all pharmaceutical fields, from drug development to their elimination in wastewater; including formulation quality control, environment and human exposure and therapeutic drug monitoring. The aim of this paper is to provide an overview of the analytical methods available for the determination of antineoplastic drugs in different matrices such as pharmaceutical formulations, biological and environmental samples. The applicability and performance of the reported methods will be critically discussed, with focus on the most commonly used antineoplastic drugs. Only conventional compounds and small molecules for targeted therapy will be considered in the present review.
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- 2017
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25. Long-term stability of ganciclovir in polypropylene containers at room temperature.
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Guichard N, Bonnabry P, Rudaz S, and Fleury-Souverain S
- Abstract
Purpose Ganciclovir is increasingly provided by hospital pharmacy production unit in a ready-to-use form, in order to improve the safety of healthcare workers and the efficiency of the organisation. The objective of this study was to develop a stability-indicating method to assay ganciclovir and determine the stability of ganciclovir in syringes (5 mg/mL) and infusion bags (0.25 and 5 mg/mL) at two different temperatures. Method Ganciclovir solutions (0.25 mg/mL and 5 mg/mL) in 0.9% sodium chloride were prepared in 50 mL polypropylene syringes or 100 mL polypropylene infusion bags and stored at 2-8℃ and 23-27℃. The chemical stability was measured using a stability-indicating Ultra High Performance Liquid Chromatography coupled to mass spectrometry method. Physical stability was assessed by visual inspection. Results No significant loss of ganciclovir under any of the tested conditions was observed in this study. All solutions remained clear through the study period. Conclusion All tested formulations remained stable for at least 185 days independently of container type, temperature or concentration studied.
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- 2017
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26. RoboDiff: combining a sample changer and goniometer for highly automated macromolecular crystallography experiments.
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Nurizzo D, Bowler MW, Caserotto H, Dobias F, Giraud T, Surr J, Guichard N, Papp G, Guijarro M, Mueller-Dieckmann C, Flot D, McSweeney S, Cipriani F, Theveneau P, and Leonard GA
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- Animals, Bacillus chemistry, Bacterial Proteins chemistry, Cattle, Crystallography, X-Ray economics, Crystallography, X-Ray methods, Equipment Design, Robotics, Software, Thermolysin chemistry, Trypsin chemistry, Crystallography, X-Ray instrumentation, Proteins chemistry
- Abstract
Automation of the mounting of cryocooled samples is now a feature of the majority of beamlines dedicated to macromolecular crystallography (MX). Robotic sample changers have been developed over many years, with the latest designs increasing capacity, reliability and speed. Here, the development of a new sample changer deployed at the ESRF beamline MASSIF-1 (ID30A-1), based on an industrial six-axis robot, is described. The device, named RoboDiff, includes a high-capacity dewar, acts as both a sample changer and a high-accuracy goniometer, and has been designed for completely unattended sample mounting and diffraction data collection. This aim has been achieved using a high level of diagnostics at all steps of the process from mounting and characterization to data collection. The RoboDiff has been in service on the fully automated endstation MASSIF-1 at the ESRF since September 2014 and, at the time of writing, has processed more than 20 000 samples completely automatically.
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- 2016
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27. A minimal molecular toolkit for mineral deposition? Biochemistry and proteomics of the test matrix of adult specimens of the sea urchin Paracentrotus lividus.
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Karakostis K, Zanella-Cléon I, Immel F, Guichard N, Dru P, Lepage T, Plasseraud L, Matranga V, and Marin F
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- Animals, Mass Spectrometry, Extracellular Matrix metabolism, Extracellular Matrix Proteins metabolism, Paracentrotus metabolism, Proteomics methods
- Abstract
Unlabelled: The sea urchin endoskeleton consists of a magnesium-rich biocalcite comprising a small amount of occluded organic macromolecules. This structure constitutes a key-model for understanding the mineral--organics interplay, and for conceiving in vitro bio-inspired materials with tailored properties. Here we employed a deep-clean technique to purify the occluded proteins from adult Paracentrotus lividus tests. We characterized them by 1- and 2D-electrophoreses, ELISA and immunoblotting, and using liquid chromatography coupled with Mass Spectrometry (nanoLC-MS/MS), we identified two metalloenzymes (carbonic anhydrase and MMP), a set of MSP130 family members, several C-type lectins (SM29, SM41, PM27) and cytoskeletal proteins. We demonstrate the effect of the protein extract on the crystals, with an in vitro crystallization assay. We suggest that this small set of biomineralization proteins may represent a 'minimal molecular crystallization toolkit'., Significance: Biominerals often exhibit superior chemical properties, when compared to their inorganic counterparts. This is due pro parte to the proteins that are occluded in the mineral. However, the limited available studies on biomineralization have not yet succeeded in identifying a minimal set of proteins directly involved in the formation of the biomineral in vivo and sufficiently required for in vitro precipitation. Indeed, the high number of proteins identified by high-throughput screening in the recent years does not encourage the possibility of recreating or tailoring the mineral in vitro. Thus, the identification of biomineralization proteins involved in protein-mineral interactions is highly awaited. In the present study, we used the sea urchin, Paracentrotus lividus (P. lividus), to identify the native proteins directly taking part in protein-mineral interactions. We employed an improved deep-clean technique to extract and purify the native occluded skeletal matrix proteins from the test and identified them by the highly sensitive technique of nanoLC-MS/MS. We show that this minimal set of proteins has a shaping effect on the formation of biocalcite in vitro. This work gives insights on the biomineralization of the sea urchin, while it paves the way for the identification of biomineralization proteins in other biomineralizing systems. Understanding the 'biologically controlled mineralization' will facilitate the in vitro formation and tailoring of biominerals in mild conditions for applications in medicine and materials science., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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28. MASSIF-1: a beamline dedicated to the fully automatic characterization and data collection from crystals of biological macromolecules.
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Bowler MW, Nurizzo D, Barrett R, Beteva A, Bodin M, Caserotto H, Delagenière S, Dobias F, Flot D, Giraud T, Guichard N, Guijarro M, Lentini M, Leonard GA, McSweeney S, Oskarsson M, Schmidt W, Snigirev A, von Stetten D, Surr J, Svensson O, Theveneau P, and Mueller-Dieckmann C
- Subjects
- Algorithms, Biopolymers chemistry, Equipment Design, Equipment Failure Analysis, Robotics instrumentation, Crystallization instrumentation, Crystallography, X-Ray instrumentation, Information Storage and Retrieval methods, Multiprotein Complexes chemistry, Multiprotein Complexes ultrastructure, Synchrotrons instrumentation
- Abstract
MASSIF-1 (ID30A-1) is an ESRF undulator beamline operating at a fixed wavelength of 0.969 Å (12.8 keV) that is dedicated to the completely automatic characterization of and data collection from crystals of biological macromolecules. The first of the ESRF Upgrade MASSIF beamlines to be commissioned, it has been open since September 2014, providing a unique automated data collection service to academic and industrial users. Here, the beamline characteristics and details of the new service are outlined.
- Published
- 2015
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29. Shell proteome of rhynchonelliform brachiopods.
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Immel F, Gaspard D, Marie A, Guichard N, Cusack M, and Marin F
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- Animals, Calcification, Physiologic physiology, Calcium Carbonate chemistry, Minerals metabolism, Peptides chemistry, Peptides metabolism, Proteomics methods, Animal Shells metabolism, Invertebrates metabolism, Proteome chemistry, Proteome metabolism
- Abstract
Brachiopods are a phylum of marine invertebrates that have an external bivalved shell to protect their living tissues. With few exceptions, this biomineralized structure is composed of calcite, mixed together with a minor organic fraction, comprising secreted proteins that become occluded in the shell structure, once formed. This organic matrix is thought to display several functions, in particular, to control mineral deposition and to regulate crystallite shapes. Thus, identifying the primary structure of matrix proteins is a prerequisite for generating bioinspired materials with tailored properties. In this study, we employed a proteomic approach to identify numerous peptides that constitute the shell proteins, in three rhynchonellid brachiopods from different localities. Our results suggest that the shell protein repertoires identified thus far, differ from that of better known calcifying metazoans, such as molluscs., (Copyright © 2015 Elsevier Inc. All rights reserved.)
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- 2015
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30. Spine and test skeletal matrices of the Mediterranean sea urchin Arbacia lixula--a comparative characterization of their sugar signature.
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Kanold JM, Guichard N, Immel F, Plasseraud L, Corneillat M, Alcaraz G, Brümmer F, and Marin F
- Subjects
- Animals, Electrophoresis, Polyacrylamide Gel, Mediterranean Sea, Microscopy, Electron, Scanning, Sea Urchins metabolism, Spectroscopy, Fourier Transform Infrared, Agglutinins metabolism, Arbacia metabolism, Calcium Carbonate metabolism
- Abstract
Calcified structures of sea urchins are biocomposite materials that comprise a minor fraction of organic macromolecules, such as proteins, glycoproteins and polysaccharides. These macromolecules are thought to collectively regulate mineral deposition during the process of calcification. When occluded, they modify the properties of the mineral. In the present study, the organic matrices (both soluble and insoluble in acetic acid) of spines and tests from the Mediterranean black sea urchin Arbacia lixula were extracted and characterized, in order to determine whether they exhibit similar biochemical signatures. Bulk characterizations were performed by mono-dimensional SDS/PAGE, FT-IR spectroscopy, and an in vitro crystallization assay. We concentrated our efforts on characterization of the sugar moieties. To this end, we determined the monosaccharide content of the soluble and insoluble organic matrices of A. lixula spines and tests by HPAE-PAD, together with their respective lectin-binding profiles via enzyme-linked lectin assay. Finally, we performed in situ localization of N-acetyl glucosamine-containing saccharides on spines and tests using gold-conjugated wheatgerm agglutinin. Our data show that the test and spine matrices exhibit different biochemical signatures with regard to their saccharidic fraction, suggesting that future studies should analyse the regulation of mineral deposition by the matrix in these two mineralized structures in detail. This study re-emphasizes the importance of non-protein moieties, i.e. sugars, in calcium carbonate systems, and highlights the need to clearly identify their function in the biomineralization process., (© 2015 FEBS.)
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- 2015
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31. The test skeletal matrix of the black sea urchin Arbacia lixula.
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Kanold JM, Immel F, Broussard C, Guichard N, Plasseraud L, Corneillat M, Alcaraz G, Brümmer F, and Marin F
- Subjects
- Amino Acid Sequence, Animals, Calcium Carbonate metabolism, Electrophoresis, Polyacrylamide Gel methods, Mass Spectrometry, Microscopy, Electron, Scanning, Minerals metabolism, Molecular Sequence Data, Monosaccharides metabolism, Proteomics, Spectroscopy, Fourier Transform Infrared, Sea Urchins anatomy & histology
- Abstract
In the field of biomineralization, the past decade has been marked by the increasing use of high throughput techniques, i.e. proteomics, for identifying in one shot the protein content of complex macromolecular mixtures extracted from mineralized tissues. Although crowned with success, this approach has been restricted so far to a limited set of key-organisms, such as the purple sea urchin Strongylocentrotus purpuratus, the pearl oyster or the abalone, leaving in the shadow non-model organisms. As a consequence, it is still unknown to what extent the calcifying repertoire varies, from group to group, at high (phylum, class), median (order, family) or low (genus, species) taxonomic rank. The present paper shows the first biochemical and proteomic characterization of the test matrix of the Mediterranean black sea urchin Arbacia lixula (Arbacioida). Our work suggests that the skeletal repertoire of A. lixula exhibits some similarities but also several differences with that of the few sea urchin species (S. purpuratus, Paracentrotus lividus), for which molecular data are already available. The differences may be attributable to the taxonomic position of the species considered: A. lixula belongs to an order - Arbacioida - that diverged more than one hundred million years ago from the Camarodonta, which includes the two species S. purpuratus and P. lividus. For the echinoid class, we suggest that large-scale proteomic screening should be performed in order to understand which molecular functions related to calcification are conserved and which ones have been co-opted for biomineralization in particular lineages., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2015
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32. Direct regulation of the pefI-srgC operon encoding the Rck invasin by the quorum-sensing regulator SdiA in Salmonella Typhimurium.
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Abed N, Grépinet O, Canepa S, Hurtado-Escobar GA, Guichard N, Wiedemann A, Velge P, and Virlogeux-Payant I
- Subjects
- Artificial Gene Fusion, DNA, Bacterial metabolism, DNA-Binding Proteins metabolism, Electrophoretic Mobility Shift Assay, Gene Expression Profiling, Gene Order, Genes, Bacterial, Genes, Reporter, Promoter Regions, Genetic, Protein Binding, Quorum Sensing, Salmonella typhimurium physiology, Surface Plasmon Resonance, Temperature, Virulence Factors genetics, Bacterial Proteins metabolism, Gene Expression Regulation, Bacterial, Operon, Salmonella typhimurium genetics, Trans-Activators metabolism, Virulence Factors biosynthesis
- Abstract
One important step for the pathogenesis of Salmonella is its ability to penetrate host cells. Recently, a new entry system involving the outer membrane protein Rck has been characterized. Previous studies have shown that the pefI-srgC locus, which contains rck, was regulated by the temperature and SdiA, the transcriptional regulator of quorum sensing in Salmonella. To decipher the regulation of rck by SdiA, we first confirmed the operon organization of the pefI-srgC locus. Using plasmid-based transcriptional fusions, we showed that only the predicted distal promoter upstream of pefI, PefIP2, displays an SdiA- and acyl-homoserine lactones-dependent activity while the predicted proximal PefIP1 promoter exhibits a very low activity independent on SdiA in our culture conditions. A direct and specific interaction of SdiA with this PefIP2 region was identified using electrophoretic mobility shift assays and surface plasmon resonance studies. We also observed that Rck expression is negatively regulated by the nucleoid-associated H-NS protein at both 25°C and 37°C. This work is the first demonstration of a direct regulation of genes by SdiA in Salmonella and will help further studies designed to identify environmental conditions required for Rck expression and consequently contribute to better characterize the role of this invasin in vivo., (© 2014 John Wiley & Sons Ltd.)
- Published
- 2014
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33. The skeleton of the staghorn coral Acropora millepora: molecular and structural characterization.
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Ramos-Silva P, Kaandorp J, Herbst F, Plasseraud L, Alcaraz G, Stern C, Corneillat M, Guichard N, Durlet C, Luquet G, and Marin F
- Subjects
- Acetic Acid pharmacology, Amination drug effects, Animals, Anthozoa drug effects, Anthozoa ultrastructure, Bone and Bones drug effects, Bone and Bones ultrastructure, Calcium Carbonate metabolism, Crystallization, Gels, Monosaccharides analysis, Proteins metabolism, Solubility, Spectroscopy, Fourier Transform Infrared, Spectrum Analysis, Raman, Anthozoa anatomy & histology, Anthozoa metabolism, Bone and Bones anatomy & histology, Bone and Bones metabolism
- Abstract
The scleractinian coral Acropora millepora is one of the most studied species from the Great Barrier Reef. This species has been used to understand evolutionary, immune and developmental processes in cnidarians. It has also been subject of several ecological studies in order to elucidate reef responses to environmental changes such as temperature rise and ocean acidification (OA). In these contexts, several nucleic acid resources were made available. When combined to a recent proteomic analysis of the coral skeletal organic matrix (SOM), they enabled the identification of several skeletal matrix proteins, making A. millepora into an emerging model for biomineralization studies. Here we describe the skeletal microstructure of A. millepora skeleton, together with a functional and biochemical characterization of its occluded SOM that focuses on the protein and saccharidic moieties. The skeletal matrix proteins show a large range of isoelectric points, compositional patterns and signatures. Besides secreted proteins, there are a significant number of proteins with membrane attachment sites such as transmembrane domains and GPI anchors as well as proteins with integrin binding sites. These features show that the skeletal proteins must have strong adhesion properties in order to function in the calcifying space. Moreover this data suggest a molecular connection between the calcifying epithelium and the skeletal tissue during biocalcification. In terms of sugar moieties, the enrichment of the SOM in arabinose is striking, and the monosaccharide composition exhibits the same signature as that of mucus of acroporid corals. Finally, we observe that the interaction of the acetic acid soluble SOM on the morphology of in vitro grown CaCO3 crystals is very pronounced when compared with the calcifying matrices of some mollusks. In light of these results, we wish to commend Acropora millepora as a model for biocalcification studies in scleractinians, from molecular and structural viewpoints.
- Published
- 2014
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34. The shell organic matrix of the crossed lamellar queen conch shell (Strombus gigas).
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Osuna-Mascaró A, Cruz-Bustos T, Benhamada S, Guichard N, Marie B, Plasseraud L, Corneillat M, Alcaraz G, Checa A, and Marin F
- Subjects
- Animal Shells ultrastructure, Animals, Calcium Carbonate chemistry, Carbohydrates analysis, Crystallization, Gastropoda ultrastructure, Glycoproteins analysis, Animal Shells chemistry, Gastropoda chemistry, Proteins analysis
- Abstract
In molluscs, the shell organic matrix comprises a large set of biomineral-occluded proteins, glycoproteins and polysaccharides that are secreted by the calcifying mantle epithelium, and are supposed to display several functions related to the synthesis of the shell. In the present paper, we have characterized biochemically the shell matrix associated to the crossed-lamellar structure of the giant queen conch Strombus gigas. The acid-soluble (ASM) and acid-insoluble (AIM) matrices represent an extremely minor fraction of the shell. Both are constituted of polydisperse and of few discrete proteins among which three fractions, obtained by preparative SDS-PAGE and named 1P3, 2P3 and 3P3, are dominant and were further characterized. Compared to other matrices, the acid-soluble matrix is weakly glycosylated (3%) and among the discrete components, only 3P3 seems noticeably glycosylated. The monosaccharide composition of the ASM shows that mannose represents the main monosaccharide. To our knowledge, this is the first report of a high ratio of this sugar in a skeletal matrix. Furthermore, the ASM interacts with the in vitro crystallization of calcium carbonate, but this interaction is moderate. It differs from that of the isolated 1P3 fraction but is similar to that of the 2P3 and 3P3 fractions. At last, antibodies developed from the 3P3 fraction were used to localize this fraction within the shell by immunogold. This study is the first one aiming at characterizing the organic matrix associated to the crossed-lamellar structure of the queen conch shell., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2014
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35. Raman spectroscopy: in vivo quick response code of skin physiological status.
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Vyumvuhore R, Tfayli A, Piot O, Le Guillou M, Guichard N, Manfait M, and Baillet-Guffroy A
- Subjects
- Aged, Female, Humans, Least-Squares Analysis, Lipids analysis, Middle Aged, Protein Folding, Skin chemistry, Skin Physiological Phenomena, Spectrum Analysis, Raman methods
- Abstract
Dermatologists need to combine different clinically relevant characteristics for a better understanding of skin health. These characteristics are usually measured by different techniques, and some of them are highly time consuming. Therefore, a predicting model based on Raman spectroscopy and partial least square (PLS) regression was developed as a rapid multiparametric method. The Raman spectra collected from the five uppermost micrometers of 11 healthy volunteers were fitted to different skin characteristics measured by independent appropriate methods (transepidermal water loss, hydration, pH, relative amount of ceramides, fatty acids, and cholesterol). For each parameter, the obtained PLS model presented correlation coefficients higher than R2=0.9. This model enables us to obtain all the aforementioned parameters directly from the unique Raman signature. In addition to that, in-depth Raman analyses down to 20 μm showed different balances between partially bound water and unbound water with depth. In parallel, the increase of depth was followed by an unfolding process of the proteins. The combinations of all these information led to a multiparametric investigation, which better characterizes the skin status. Raman signal can thus be used as a quick response code (QR code). This could help dermatologic diagnosis of physiological variations and presents a possible extension to pathological characterization.
- Published
- 2014
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36. The skeletal proteome of the coral Acropora millepora: the evolution of calcification by co-option and domain shuffling.
- Author
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Ramos-Silva P, Kaandorp J, Huisman L, Marie B, Zanella-Cléon I, Guichard N, Miller DJ, and Marin F
- Subjects
- Amino Acid Sequence, Animals, Anthozoa classification, Anthozoa metabolism, Calcium Carbonate metabolism, Extracellular Matrix chemistry, Mass Spectrometry, Molecular Sequence Annotation, Molecular Sequence Data, Protein Structure, Tertiary, Proteome chemistry, Proteome classification, Proteome metabolism, Sequence Alignment, Sequence Homology, Amino Acid, Anthozoa genetics, Calcification, Physiologic genetics, Evolution, Molecular, Phylogeny, Proteome genetics
- Abstract
In corals, biocalcification is a major function that may be drastically affected by ocean acidification (OA). Scleractinian corals grow by building up aragonitic exoskeletons that provide support and protection for soft tissues. Although this process has been extensively studied, the molecular basis of biocalcification is poorly understood. Notably lacking is a comprehensive catalog of the skeleton-occluded proteins-the skeletal organic matrix proteins (SOMPs) that are thought to regulate the mineral deposition. Using a combination of proteomics and transcriptomics, we report the first survey of such proteins in the staghorn coral Acropora millepora. The organic matrix (OM) extracted from the coral skeleton was analyzed by mass spectrometry and bioinformatics, enabling the identification of 36 SOMPs. These results provide novel insights into the molecular basis of coral calcification and the macroevolution of metazoan calcifying systems, whereas establishing a platform for studying the impact of OA at molecular level. Besides secreted proteins, extracellular regions of transmembrane proteins are also present, suggesting a close control of aragonite deposition by the calicoblastic epithelium. In addition to the expected SOMPs (Asp/Glu-rich, galaxins), the skeletal repertoire included several proteins containing known extracellular matrix domains. From an evolutionary perspective, the number of coral-specific proteins is low, many SOMPs having counterparts in the noncalcifying cnidarians. Extending the comparison with the skeletal OM proteomes of other metazoans allowed the identification of a pool of functional domains shared between phyla. These data suggest that co-option and domain shuffling may be general mechanisms by which the trait of calcification has evolved.
- Published
- 2013
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37. The shell-forming proteome of Lottia gigantea reveals both deep conservations and lineage-specific novelties.
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Marie B, Jackson DJ, Ramos-Silva P, Zanella-Cléon I, Guichard N, and Marin F
- Subjects
- Amino Acid Sequence, Animal Shells enzymology, Animal Shells ultrastructure, Animals, Carbonic Anhydrases chemistry, Carbonic Anhydrases isolation & purification, Carbonic Anhydrases metabolism, Cyclophilins isolation & purification, Cyclophilins metabolism, Electrophoresis, Polyacrylamide Gel, Epidermal Growth Factor chemistry, Epidermal Growth Factor isolation & purification, Epidermal Growth Factor metabolism, Extracellular Matrix Proteins chemistry, Extracellular Matrix Proteins isolation & purification, Extracellular Matrix Proteins metabolism, Glycoside Hydrolases isolation & purification, Glycoside Hydrolases metabolism, Molecular Sequence Data, Peptide Fragments chemistry, Peroxidases chemistry, Peroxidases isolation & purification, Peroxidases metabolism, Protein Structure, Tertiary, Proteome chemistry, Proteome isolation & purification, Sequence Analysis, Protein, Sequence Homology, Amino Acid, Tandem Mass Spectrometry, Animal Shells metabolism, Gastropoda metabolism, Proteome metabolism
- Abstract
Proteins that are occluded within the molluscan shell, the so-called shell matrix proteins (SMPs), are an assemblage of biomolecules attractive to study for several reasons. They increase the fracture resistance of the shell by several orders of magnitude, determine the polymorph of CaCO(3) deposited, and regulate crystal nucleation, growth initiation and termination. In addition, they are thought to control the shell microstructures. Understanding how these proteins have evolved is also likely to provide deep insight into events that supported the diversification and expansion of metazoan life during the Cambrian radiation 543 million years ago. Here, we present an analysis of SMPs isolated form the CaCO(3) shell of the limpet Lottia gigantea, a gastropod that constructs an aragonitic cross-lamellar shell. We identified 39 SMPs by combining proteomic analysis with genomic and transcriptomic database interrogations. Among these proteins are various low-complexity domain-containing proteins, enzymes such as peroxidases, carbonic anhydrases and chitinases, acidic calcium-binding proteins and protease inhibitors. This list is likely to contain the most abundant SMPs of the shell matrix. It reveals the presence of both highly conserved and lineage-specific biomineralizing proteins. This mosaic evolutionary pattern suggests that there may be an ancestral molluscan SMP set upon which different conchiferan lineages have elaborated to produce the diversity of shell microstructures we observe nowadays., (© 2012 The Authors Journal compilation © 2012 FEBS.)
- Published
- 2013
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38. Comparative ultrastructure and carbohydrate composition of gastroliths from astacidae, cambaridae and parastacidae freshwater crayfish (crustacea, decapoda).
- Author
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Luquet G, Fernández MS, Badou A, Guichard N, Roy NL, Corneillat M, Alcaraz G, and Arias JL
- Abstract
Crustaceans have to cyclically replace their rigid exoskeleton in order to grow. Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish) elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we studied the ultrastructure of gastroliths from freshwater crayfish by using a combination of microscopic and physical techniques. Because sugars are also molecules putatively involved in the elaboration process of these biomineralizations, we also determined their carbohydrate composition. This study was performed in a comparative perspective on crayfish species belonging to the infra-order Astacidea (Decapoda, Malacostraca): three species from the Astacoidea superfamily and one species from the Parastacoidea superfamily. We observed that all the gastroliths exhibit a similar dense network of protein-chitin fibers, from macro- to nanoscale, within which calcium is precipitated as amorphous calcium carbonate. Nevertheless, they are not very similar at the molecular level, notably as regards their carbohydrate composition. Besides glucosamine, the basic carbohydrate component of chitin, we evidenced the presence of other sugars, some of which are species-specific like rhamnose and galacturonic acid whereas xylose and mannose could be linked to proteoglycan components.
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- 2012
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39. Identification of two carbonic anhydrases in the mantle of the European Abalone Haliotis tuberculata (Gastropoda, Haliotidae): phylogenetic implications.
- Author
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LE Roy N, Marie B, Gaume B, Guichard N, Delgado S, Zanella-Cléon I, Becchi M, Auzoux-Bordenave S, Sire JY, and Marin F
- Subjects
- Animals, Base Sequence, Calcification, Physiologic genetics, Cloning, Molecular, DNA Primers genetics, DNA, Complementary genetics, Electrophoresis, Polyacrylamide Gel, Gastropoda genetics, Likelihood Functions, Models, Genetic, Molecular Sequence Data, Polymerase Chain Reaction, Proteomics, Real-Time Polymerase Chain Reaction, Sequence Analysis, DNA, Species Specificity, Animal Shells enzymology, Calcification, Physiologic physiology, Carbonic Anhydrases genetics, Gastropoda enzymology, Models, Biological, Phylogeny
- Abstract
Carbonic anhydrases (CAs) represent a diversified family of metalloenzymes that reversibly catalyze the hydration of carbon dioxide. They are involved in a wide range of functions, among which is the formation of CaCO(3) skeletons in metazoans. In the shell-forming mantle tissues of mollusks, the location of the CA catalytic activity is elusive and gives birth to contradicting views. In the present paper, using the European abalone Haliotis tuberculata, a key model gastropod in biomineralization studies, we identified and characterized two CAs (htCA1 and htCA2) that are specific of the shell-forming mantle tissue. We analyzed them in a phylogenetic context. Combining various approaches, including proteomics, activity tests, and in silico analyses, we showed that htCA1 is secreted but is not incorporated in the organic matrix of the abalone shell and that htCA2 is transmembrane. Together with previous studies dealing with molluskan CAs, our findings suggest two possible modes of action for shell mineralization: the first mode applies to, for example, the bivalves Unio pictorum and Pinctada fucata, and involves a true CA activity in their shell matrix; the second mode corresponds to, for example, the European abalone, and does not include CA activity in the shell matrix. Our work provides new insight on the diversity of the extracellular macromolecular tools used for shell biomineralization study in mollusks., (© 2012 WILEY PERIODICALS, INC.)
- Published
- 2012
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40. Novel molluskan biomineralization proteins retrieved from proteomics: a case study with Upsalin.
- Author
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Ramos-Silva P, Benhamada S, Le Roy N, Marie B, Guichard N, Zanella-Cléon I, Plasseraud L, Corneillat M, Alcaraz G, Kaandorp J, and Marin F
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Electrophoresis, Microscopy, Electron, Scanning, Molecular Sequence Data, Mollusca, Proteomics methods, Minerals chemistry, Minerals metabolism, Proteins chemistry, Proteins metabolism
- Abstract
The formation of the molluskan shell is regulated by an array of extracellular proteins secreted by the calcifying epithelial cells of the mantle. These proteins remain occluded within the recently formed biominerals. To date, many shell proteins have been retrieved, but only a few of them, such as nacreins, have clearly identified functions. In this particular case, by combining molecular biology and biochemical approaches, we performed the molecular characterization of a novel protein that we named Upsalin, associated with the nacreous shell of the freshwater mussel Unio pictorum. The full sequence of the upsalin transcript was obtained by RT-PCR and 5'/3' RACE, and the expression pattern of the transcript was studied by PCR and qPCR. Upsalin is a 12 kDa protein with a basic theoretical pI. The presence of Upsalin in the shell was demonstrated by extraction of the acetic-acid-soluble nacre matrix, purification of a shell protein fraction by mono-dimensional preparative SDS-PAGE, and by submitting this fraction, after trypsic digestion, to nano-LC-MS/MS. In vitro experiments with the purified protein showed that it interferes poorly with the precipitation of calcium carbonate. Homology searches also could not affiliate Upsalin to any other protein of known function, leaving open the question of its exact role in shell formation. An antibody raised against an immunogenic peptide of Upsalin was found to be specific to this protein and was subsequently assayed for immunogold localization of the target protein in the shell, revealing the ubiquitous presence of Upsalin in the nacreous and prismatic layers. Recently, with the application of high-throughput proteomic studies to shells, the number of candidate proteins without clear functions has been increasing exponentially. The Upsalin example highlights the crucial need, for the scientific community dealing with biomineralization in general, to dedicate the coming years to designing experimental approaches, such as gene silencing, that focus on the functions of mineral-associated proteins., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2012
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41. Effects of prolonged-release melatonin and zolpidem on postural stability in older adults.
- Author
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Otmani S, Metzger D, Guichard N, Danjou P, Nir T, Zisapel N, and Katz A
- Subjects
- Analysis of Variance, Cross-Over Studies, Double-Blind Method, Female, Follow-Up Studies, Humans, Male, Middle Aged, Time Factors, Zolpidem, Antioxidants administration & dosage, Drug Delivery Systems methods, Hypnotics and Sedatives pharmacology, Melatonin administration & dosage, Postural Balance drug effects, Pyridines pharmacology
- Abstract
Objectives: A prolonged-release formulation of melatonin (PR-M) is indicated for insomnia in patients aged 55 years and older. Because hypnotics result in impairments of body sway, it was important to evaluate the effect of 2 mg PR-M on postural stability in older adults at night., Methods: Twenty-four healthy volunteers (12 women, 12 men, aged 55-64 years) completed a randomized, double-blind, single-dose, three-way crossover study of postural stability of PR-M 2 mg, zolpidem 10 mg (active control) or placebo. Subjects were tested for body sway 30 min before, 1.5 and 4 h after dosing. Parameters tested were the area of the 95% confidence ellipse enclosing the center of pressure (COP; [A95]) and COP path length., Results: Zolpidem significantly increased the A95 (both eyes conditions at all time points) and path length of COP. PR-M had no effect on A95 (both "eyes closed" and "eyes open" conditions at all time points) compared with placebo and increased COP path length by 10% at 4 h post-dose in open but not closed eyes condition. No serious adverse events were observed., Conclusions: In older adults, evening PR-M intake did not impair postural stability during the night. The postural instability with zolpidem demonstrated assay sensitivity and validated the outcome., (Copyright © 2012 John Wiley & Sons, Ltd.)
- Published
- 2012
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42. The shell matrix of the pulmonate land snail Helix aspersa maxima.
- Author
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Pavat C, Zanella-Cléon I, Becchi M, Medakovic D, Luquet G, Guichard N, Alcaraz G, Dommergues JL, Serpentini A, Lebel JM, and Marin F
- Subjects
- Amino Acids analysis, Animal Shells ultrastructure, Animals, Calcium Carbonate chemistry, Electrophoresis, Gel, Two-Dimensional, Electrophoresis, Polyacrylamide Gel, France, Immunohistochemistry, Microscopy, Electron, Scanning, Monosaccharides analysis, Species Specificity, Tandem Mass Spectrometry, X-Ray Diffraction, Animal Shells chemistry, Helix, Snails chemistry, Proteins analysis
- Abstract
In mollusks, the shell mineralization process is controlled by an array of proteins, glycoproteins and polysaccharides that collectively constitute the shell matrix. In spite of numerous researches, the shell protein content of a limited number of model species has been investigated. This paper presents biochemical data on the common edible land snail Helix aspersa maxima, a model organism for ecotoxicological purposes, which has however been poorly investigated from a biomineralization viewpoint. The shell matrix of this species was extracted and analyzed biochemically for functional in vitro inhibition assay, for amino acid and monosaccharides compositions. The matrix was further analyzed on 1 and 2D gels and short partial protein sequences were obtained from 2D gel spots. Serological comparisons were established with a set of heterologous antibodies, two of which were subsequently used for subsequent immunogold localization of matrix components. Our data suggest that the shell matrix of Helix aspersa maxima may differ widely from the shell secretory repertoire of the marine mollusks studied so far, such as the gastropod Haliotis or the pearl oyster Pinctada. In particular, most of the biochemical properties generally attributed to soluble shell matrices, such as calcium-binding capability, or the capacity to interfere in vitro with the precipitation of calcium carbonate or to inhibit the precipitation of calcium carbonate, were not recorded with this matrix. This drastic change in the biochemical properties of the landsnail shell matrix puts into question the existence of a unique molecular model for molluscan shell formation, and may be related to terrestrialisation., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2012
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43. Novel proteins from the calcifying shell matrix of the Pacific oyster Crassostrea gigas.
- Author
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Marie B, Zanella-Cléon I, Guichard N, Becchi M, and Marin F
- Subjects
- Animals, Chromatography, Liquid, Computational Biology, Expressed Sequence Tags, Gene Library, Microscopy, Electron, Scanning, Proteomics methods, Tandem Mass Spectrometry, Trypsin, Animal Shells chemistry, Crassostrea chemistry, Proteins analysis
- Abstract
The shell of the Pacific oyster Crassostrea gigas is composed of more than 99% CaCO₃ and of around 0.5% of occluded organic matrix. According to classical views, this matrix is supposed to regulate the shell mineral deposition. In this study, we developed one of the first proteomic approaches applied to mollusk shell in order to characterise the calcifying matrix proteins. The insoluble organic matrix, purified after demineralisation of the shell powder, was digested with trypsin enzyme, and separated on nano-LC, prior to nanospray quadrupole/time-of-flight analysis. MS/MS spectra were searched against the above 220,000 EST sequences available in the public database for Crassostrea. Using this approach, we were able to identify partial or full-length sequence transcripts that encode eight novel shell matrix proteins.
- Published
- 2011
- Full Text
- View/download PDF
44. Proteomic identification of novel proteins from the calcifying shell matrix of the Manila clam Venerupis philippinarum.
- Author
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Marie B, Trinkler N, Zanella-Cleon I, Guichard N, Becchi M, Paillard C, and Marin F
- Subjects
- Amino Acid Sequence, Animals, Microscopy, Electron, Scanning, Proteins genetics, Animal Shells metabolism, Bivalvia metabolism, Gene Expression Regulation physiology, Proteins metabolism, Proteomics methods
- Abstract
The shell of the Manila clam Venerupis philippinarum is composed of more than 99% calcium carbonate and of a small amount of organic matrix (around 0.2%). In this study, we developed one of the first proteomic approaches applied to mollusc shell in order to characterise the matrix proteins that are believed to be essential for the formation of the biomineral. The insoluble organic matrix, purified after demineralisation of the shell powder with cold acetic acid (5%), was digested with trypsin enzyme and then separated on nano-LC prior to nanospray/quadrupole time-of-flight analysis. MS/MS spectra were searched against the above 11,000 EST sequences available on the NCBI public database for Venerupis. Using this approach, we were able to identify partial or full-length sequence transcripts that encode for shell matrix proteins. These include three novel shell proteins whose sequences do not present any homologous proteins or already described domains, two putative protease inhibitor proteins containing Kazal-type domains, and a putative Ca(2+)-binding protein containing two EF-hand domains. Biomineral formation and evolutionary implications are discussed.
- Published
- 2011
- Full Text
- View/download PDF
45. Variability of shell repair in the Manila clam Ruditapes philippinarum affected by the Brown Ring Disease: a microstructural and biochemical study.
- Author
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Trinkler N, Guichard N, Labonne M, Plasseraud L, Paillard C, and Marin F
- Subjects
- Animals, Bivalvia physiology, Bivalvia ultrastructure, Electrophoresis, Polyacrylamide Gel, Enzyme-Linked Immunosorbent Assay, Hemolymph physiology, Bivalvia microbiology, Vibrio physiology
- Abstract
For more than two decades, the Manila clam Ruditapes philippinarum has been regularly affected by Brown Ring Disease (BRD), an epizootic event caused by the bacterium Vibrio tapetis and characterized by the development of a brown deposit on the inner face of valves. Although BRD infection is often lethal, some clams recover by mineralizing a new repair shell layer, which covers the brown deposit and fully isolates it from living tissues. In order to understand this specific shell repair process, the microstructures of repaired zones were compared to those of shells unaffected by BRD. In addition, the organic matrix associated with unaffected shells and to repair patches were extracted and compared by biochemical and immunological techniques. Our results show that the repaired zones exhibit microstructures that resemble the so-called homogeneous microstructure of the internal layer, with some marked differences, like the development of crossed-acicular crystals, which form chevron-like patterns. In the three tested batches of repaired layers, the matrices exhibit certain heterogeneity, i.e., they are partially to widely different from the ones of shells unaffected by BRD, as illustrated by SDS-PAGE and by serological comparisons. Our results strongly suggest a modification of the secretory regime of calcifying mantle cells during the shell repair process. Polyclonal antibodies, which were developed against specific protein fractions of the shell, represent relevant tools for localizing by immunohistology the cells responsible for the repair., (Copyright © 2010 Elsevier Inc. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
46. Nacre calcification in the freshwater mussel Unio pictorum: carbonic anhydrase activity and purification of a 95 kDa calcium-binding glycoprotein.
- Author
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Marie B, Luquet G, Bédouet L, Milet C, Guichard N, Medakovic D, and Marin F
- Subjects
- Amino Acid Sequence, Animals, Bivalvia classification, Bivalvia enzymology, Calcification, Physiologic, Calcium-Binding Proteins isolation & purification, Carbonates, Enzyme Activation, Gels, Glycoproteins isolation & purification, Mass Spectrometry, Microscopy, Electron, Scanning, Molecular Weight, Proteomics, Sequence Analysis, Solubility, Bivalvia anatomy & histology, Bivalvia metabolism, Calcium metabolism, Calcium-Binding Proteins metabolism, Carbonic Anhydrases metabolism, Fresh Water, Glycoproteins metabolism
- Abstract
The formation of the molluscan shell is finely tuned by macromolecules of the shell organic matrix. Previous results have shown that the acid-soluble fraction of the nacre matrix of the freshwater paleoheterodont bivalve Unio pictorum shell displays a number of remarkable properties, such as calcium-binding activity, the presence of extensive glycosylations and the capacity to interfere at low concentration with in vitro calcium carbonate precipitation. Here we have found that the nacre-soluble matrix exhibits a carbonic anhydrase activity, an important function in calcification processes. This matrix is composed of three main proteinaceous discrete fractions. The one with the highest apparent molecular weight is a 95 kDa glycoprotein that is specific to the nacreous layer. P95, as it is provisionally named, is enriched in Gly, Glx and Asx and exhibits an apparent pI value of approximately 4, or approximately 7 when chemically deglycosylated. Furthermore, its glycosyl moiety, consisting of sulfated polysaccharides, is involved in calcium binding. Purified fractions of the three main proteins were digested with trypsin, and the resulting peptides were analysed by mass spectrometry. Our results suggest that identical peptides are constitutive domains of the different proteins. Partial primary structures were obtained by de novo sequencing and compared with known sequences from other mollusc shell proteins. Our results are discussed from an evolutionary viewpoint.
- Published
- 2008
- Full Text
- View/download PDF
47. Facilitated transport of diuron and glyphosate in high copper vineyard soils.
- Author
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Dousset S, Jacobson AR, Dessogne JB, Guichard N, Baveye PC, and Andreux F
- Subjects
- Adsorption, Copper chemistry, Diuron chemistry, Drug Interactions, Environmental Monitoring methods, Glycine analysis, Glycine chemistry, Herbicides analysis, Herbicides chemistry, Protons, Soil Pollutants chemistry, Glyphosate, Copper analysis, Diuron analysis, Glycine analogs & derivatives, Soil analysis, Soil Pollutants analysis
- Abstract
The fate of organic herbicides applied to agricultural fields may be affected by other soil amendments, such as copper applied as a fungicide. The effect of copper on the leaching of diuron and glyphosate through a granitic and a calcareous soil was studied in the laboratory using sieved-soil columns. Each soil was enriched with copper sulfate to obtain soil copper concentrations of 125, 250, 500, and 1000 mg kg(-1). Glyphosate leaching was influenced by soil pH and copper concentration, whereas diuron leaching was not. In the calcareous soil, glyphosate leaching decreased as copper levels increased from 17 mg kg(-1) (background) to 500 mg kg(-1). In the granitic soil, glyphosate leaching increased as copper levels increased from 34 mg kg(-1) (background) to 500 mg kg(-1). The shapes of the copper elution curves in presence of glyphosate were similar to shapes of the glyphosate curves, suggesting the formation of Cu-glyphosate complexes that leach through the soil. Soil copper concentration does not influence diuron leaching. In contrast, increasing copper concentrations reduces glyphosate leaching through calcareous soils, and conversely, increases glyphosate leaching through granitic soils. Our findings suggest that the risk of groundwater contamination by glyphosate increases in granitic soils with elevated copper concentrations.
- Published
- 2007
- Full Text
- View/download PDF
48. The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in nacre mineralization.
- Author
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Marie B, Luquet G, Pais De Barros JP, Guichard N, Morel S, Alcaraz G, Bollache L, and Marin F
- Subjects
- Amino Acids analysis, Animals, Carbohydrates analysis, Electrophoresis, Gel, Two-Dimensional, Electrophoresis, Polyacrylamide Gel, Extracellular Matrix physiology, Fresh Water, Spectroscopy, Fourier Transform Infrared, Bivalvia chemistry, Calcification, Physiologic, Extracellular Matrix chemistry, Glycoproteins physiology, Polysaccharides physiology
- Abstract
Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the insoluble matrix comprises a high amount of glucosamine. Furthermore, a high ratio of the carbohydrates of the soluble matrix is sulfated. Electrophoretic analysis of the acid-soluble matrix revealed discrete bands. Stains-All, Alcian Blue, periodic acid/Schiff and autoradiography with (45)Ca after electrophoretic separation revealed three major polyanionic calcium-binding glycoproteins, which exhibit an apparent molecular mass of 95, 50 and 29 kDa, respectively. Two-dimensional gel electrophoresis shows that these bands, provisionally named P95, P50 and P29, are composed of numerous isoforms, the majority of which have acidic isoelectric points. Chemical deglycosylation of the matrix with trifluoromethanesulfonic acid induces a drastic shift of both the apparent molecular mass and the isoelectric point of these matrix components. This treatment induces also a modification of the shape of CaCO(3) crystals grown in vitro and a loss of the calcium-binding ability of two of the main matrix proteins (P95 and P50). Our findings strongly suggest that post-translational modifications display important functions in mollusc shell calcification.
- Published
- 2007
- Full Text
- View/download PDF
49. Diuron mobility through vineyard soils contaminated with copper.
- Author
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Jacobson AR, Dousset S, Guichard N, Baveye P, and Andreux F
- Subjects
- Copper, Environmental Monitoring methods, Fungicides, Industrial, Humic Substances, Models, Theoretical, Poaceae, Soil, Water Movements, Agriculture, Diuron analysis, Environmental Pollution, Herbicides analysis, Soil Pollutants analysis, Wine
- Abstract
The herbicide diuron is frequently applied to vineyard soils in Burgundy, along with repeated treatments with Bordeaux mixture (a blend of copper sulfate and calcium hydroxide) that result in elevated copper concentrations. Cu could in principle affect the fate and transport of diuron or its metabolites in the soil either directly by complexation or indirectly by altering the populations or activity of microbes involved in their degradation. To assess the effect of high Cu concentrations on diuron transport, an experiment was designed with ten undisturbed columns of calcareous and acidic soils contaminated with 17--509 mg kg(-1) total Cu (field-applied). Grass was planted on three columns. Diuron was applied to the soils in early May and in-ground lysimeters were exposed to outdoor conditions until November. Less than 1.2% of the diuron applied was found in the leachates as diuron or its metabolites. Higher concentrations were found in the effluents from the grass-covered columns (0.1--0.45%) than from the bare-soil columns (0.02--0.14%), and they were correlated with increases in dissolved organic carbon. The highest amounts of herbicide were measured in acidic-soil column leachates (0.98--1.14%) due to the low clay and organic matter contents of these soils. Cu also leached more readily through the acidic soils (32.8--1042 microg) than in the calcareous soils (9.5--63.4 microg). Unlike in the leachates, the amount of diuron remaining in the soils at the end of the experiment was weakly related to the Cu concentrations in the soils.
- Published
- 2005
- Full Text
- View/download PDF
50. Caspartin and calprismin, two proteins of the shell calcitic prisms of the Mediterranean fan mussel Pinna nobilis.
- Author
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Marin F, Amons R, Guichard N, Stigter M, Hecker A, Luquet G, Layrolle P, Alcaraz G, Riondet C, and Westbroek P
- Subjects
- Amino Acid Sequence, Animals, Crystallization, Electrophoresis, Immunoassay, Molecular Sequence Data, Bivalvia chemistry, Bivalvia physiology, Calcium Carbonate metabolism, Glycoproteins chemistry, Glycoproteins isolation & purification
- Abstract
We used the combination of preparative electrophoresis and immunological detection to isolate two new proteins from the shell calcitic prisms of Pinna nobilis, the Mediterranean fan mussel. The amino acid composition of these proteins was determined. Both proteins are soluble, intracrystalline, and acidic. The 38-kDa protein is glycosylated; the 17-kDa one is not. Ala, Asx, Thr, and Pro represent the dominant residues of the 38-kDa protein, named calprismin. An N-terminal sequence was obtained from calprismin. This sequence, which comprises a pattern of 4 cysteine residues, is not related to any known protein. The second protein, named caspartin, exhibits an unusual amino acid composition, since Asx constitutes by far the main amino acid residue. Preliminary sequencing surprisingly suggests that the first 75 N-terminal residues are all Asp. Caspartin self-aggregates spontaneously into multimers. In vitro tests show that it inhibits the precipitation of calcium carbonate. Furthermore, it strongly interferes with the growth of calcite crystals. A polyclonal antiserum raised against caspartin was used to localize this protein in the shell by immunogold. The immunolocalization demonstrates that caspartin is distributed within the prisms and makes a continuous film at the interface between the prisms and the surrounding insoluble sheets. Our finding emphasizes the prominent role of aspartic acid-rich proteins for the building of calcitic prisms among molluscs.
- Published
- 2005
- Full Text
- View/download PDF
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