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3. Prevalence and location of coronary artery disease in anomalous aortic origin of coronary arteries

Author

Zendjebil, Sandra, Koutsoukis, Athanasios, Rodier, Thomas, Hyafil, Fabien, Halna du Fretay, Xavier, Dupouy, Patrick, Juliard, Jean-Michel, Farnoud, Reza, Ou, Phalla, Laissy, Jean-Pierre, Couffignal, Camille, Aubry, Pierre, Abi Khalil, Wissam, Aguirre, Luc, Akesbi, Abdel, Aubry, Pierre, Banus, Yves, Belle, Loic, Benamer, Hakim, Biron, Yves, Boiffard, Emmanuel, Bouallal, Rachid, Boudvillain, Olivier, Bourkaïb, Ryad, Brasselet, Camille, Bressollette, Erwan, Brunel, Philippe, Champagnac, Didier, Coco, Michel, Commeau, Philippe, Cook, Stephane, Couppie, Philippe, de Poli, Fabien, Delorme, Laurent, Descoutures, Fleur, Didier, Romain, Ducrocq, Gregory, Dupouy, Patrick, Durier, Chloé, El Mahmoud, Rami, Estève, Jean-Baptiste, Faurie, Benjamin, Garbarz, Eric, Georges, Jean-Louis, Gerardin, Benoit, Gibault-Genty, Géraldine, Gilard, Martine, Godin, Matthieu, Goy, Jean-Jacques, Haffner-Debus, Claire, Halna du Fretay, Xavier, Hanssen, Michel, Hascoët, Sébastien, Jacquemin, Laurent, Jeanneteau, Julien, Joseph, Thierry, Juliard, Jean-Michel, Karsenty, Bernard, Koning, René, La Scala, Eugenio, Leddet, Pierre, Lemesle, Gilles, Leurent, Guillaume, Levy, Raphy, Livarek, Bernard, Loubeyre, Christophe, Maillard, Luc, Mangin, Lionel, Marlière, Stéphanie, Nejjari, Mohammed, Ohlmann, Patrick, Poulos, Nabil, Py, Antoine, Ranc, Sylvain, Rialan, Alain, Roriz, Ricardo, Rougier, Pierre, Staat, Patrick, Thuaire, Christophe, Togni, Mario, van Rothem, Jérôme, Varenne, Olivier, and Voudris, Vassilis

Published
2024
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4. Impact of residual inflammation on myocardial recovery and cardiovascular outcome in Takotsubo patients

Author

Lucie Lachmet‐Thebaud, Benjamin Marchandot, Kensuke Matsushita, Chisato Sato, Charlotte Dagrenat, Stephane Greciano, Fabien De Poli, Pierre Leddet, Marilou Peillex, Sébastien Hess, Adrien Carmona, Charline Jimenez, Joe Heger, Antje Reydel, Patrick Ohlmann, Laurence Jesel, and Olivier Morel

Subjects
Takotsubo syndrome, Residual high inflammatory response, Systemic inflammatory response syndrome, Predictive factor, Late cardiac death, Late cardiovascular outcome, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Aims Recent insights have emphasized the importance of myocardial and systemic inflammation in Takotsubo syndrome (TTS). In a large registry of unselected patients, we sought to evaluate whether residual high inflammatory response (RHIR) could impact cardiovascular outcome after TTS. Methods and results Patients with TTS were retrospectively included between 2008 and 2018 in three general hospitals. Three hundred eighty‐five patients with TTS were split into three subgroups, according to tertiles of C‐reactive protein (CRP) levels at discharge (CRP 19 mg/L). The primary endpoint was the impact of RHIR, defined as CRP >19 mg/L at discharge, on cardiac death or hospitalization for heart failure. Follow up was obtained in 382 patients (99%) after a median of 747 days. RHIR patients were more likely to have a history of cancer or a physical trigger. Left ventricular ejection fraction (LVEF) at admission and at discharge were comparable between groups. By contrast, RHIR was associated with lower LVEF at follow up (61.7% vs. 60.7% vs. 57.9%; P = 0.004) and increased cardiac late mortality (0% vs. 0% vs. 10%; P = 0.001). By multivariate Cox regression analysis, RHIR was an independent predictor of cardiac death or hospitalization for heart failure (hazard ratio: 1.87; 95% confidence interval: 1.08 to 3.25; P = 0.025). Conclusions Residual high inflammatory response was associated with impaired LVEF at follow up and was evidenced as an independent factor of cardiovascular events. All together, these findings underline RHIR patients as a high‐risk subgroup, to target in future clinical trials with specific therapies to attenuate RHIR.

Published
2021
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6. Behavioral avoidance and biological safety of vetiver oil and its constituents against Aedes aegypti (L.), Aedes albopictus (Skuse) and Culex quinquefasciatus Say

Author

Jirod Nararak, Carole Di Giorgio, Kanutcharee Thanispong, Chutipong Sukkanon, Unchalee Sanguanpong, Valerie Mahiou-Leddet, Evelyne Ollivier, Theeraphap Chareonviriyaphap, and Sylvie Manguin

Subjects
Plant-based repellent, contact irritancy, spatial repellent, cytotoxicity, mosquito vectors, terpinen-4-ol, Zoology, QL1-991
Abstract

Numerous plant-based repellents are widely used for personal protection against host-seeking mosquitoes. Vitiveria zizanioides (L.) Nash essential oil and its constituents have demonstrated various mosquito repellent activities. In this study, three chemical actions of vetiver oil and five constituents (terpinen-4-ol, α-terpineol, valencene, vetiverol and vetivone) were characterized against Aedes aegypti, Aedes albopictus and Culex quinquefasciatus by using the high-throughput screening assay system (HITSS). Significant contact escape responses in Ae. aegypti and Ae. albopictus to all test compounds at concentrations between 2.5 and 5% were observed. Spatial repellency responses were also observed in some tested mosquito populations depending upon concentrations. The most significant toxic response on mosquitoes was found at the highest concentration, except for vetivone which had no toxic effect on Ae. aegypti and Ae. albopictus. Results on phototoxic and genotoxic hazard revealed that vetiver oil and their constituents showed no phototoxic potential or any significant genotoxic response. In conclusion, vetiver oil and two constituents, valencene and vetiverol, are potentials as active ingredients for mosquito repellency and present no toxicity.

Published
2022
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10. Infarctus à coronaires saines : une faible élévation de la troponine ou un long délai entre l'infarctus et l'examen sont-ils des facteurs limitant la rentabilité diagnostique de l'imagerie par résonance magnétique ? Données de l’étude CRIMINAL du CNCH.

Author

Noirclerc, N., primary, Dagrenat, C., additional, Rangé, G., additional, Georges, J.L., additional, Nallet, O., additional, Delarche, N., additional, Ferrier, N., additional, Melay, M., additional, Clerc, J., additional, Barbou, F., additional, Jeannot, C., additional, Delaunay, R., additional, Michel, L., additional, Madiot, H., additional, Leddet, P., additional, and Belle, L., additional

Published
2022
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12. Interobserver variability in the classification of congenital coronary abnormalities: A substudy of the anomalous connections of the coronary arteries registry

Author

Koutsoukis, Athanasios, Halna du Fretay, Xavier, Dupouy, Patrick, Ou, Phalla, Laissy, Jean‐Pierre, Juliard, Jean‐Michel, Hyafil, Fabien, Aubry, Pierre, Abi Khalil, W., Aguirre, L., Akesbi, A., Aubry, P., Banus, Y., Belle, L., Benamer, H., Biron, Y., Boiffard, E., Bouallal, R., Boudvillain, O., Bourkaïb, R., Brasselet, C., Bressollette, E., Brunel, P., Champagnac, D., Coco, M., Commeau, P., Cook, S., Couppie, P., de Poli, F., Delorme, L., Descoutures, F., Didier, R., Ducrocq, G., Dupouy, P., Durier, C., El Mahmoud, R., Estève, J.‐B., Faurie, B., Garbarz, E., Georges, J.‐L., Gérardin, B., Gibault‐Genty, G., Gilard, M., Godin, M., Goy, J.‐J., Haffner‐Debus, C., Halna du Fretay, X., Hanssen, M., Hascoët, S., Jacquemin, L., Jeanneteau, J., Joseph, T., Juliard, J.‐M., Karsenty, B., Koning, R., La Scala, E., Leddet, P., Lemesle, G., Leurent, G., Levy, R., Livarek, B., Loubeyre, C., Maillard, L., Mangin, L., Marlière, S., Nejjari, M., Ohlmann, P., Poulos, N., Py, A., Ranc, S., Rialan, A., Roriz, R., Rougier, P., Staat, P., Thuaire, C., Togni, M., van Rothem, J., Varenne, O., and Voudris, V.

Published
2017
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16. Antiplasmodial and cytotoxic activity of lanostane type triterpenoids isolated from Leplaea mayombensis.

Author

Sidjui, Lazare Sidjui, Soh, Desiré, Herbette, Gaëtan, Toghueo, Rufin Marie Kouipou, Folefoc, Gabriel Ngosong, Mahiou-Leddet, Valérie, Baghdikian, Béatrice, and Ali, Muhammad Shaiq

Abstract

Leplaeric acid E 5 , leplazarin 6a and 21-epileplazarin 6b , three new 3,4- seco -lanostane type triterpenes have been isolated from the stem bark of Leplaea mayombensis (Pellegr.) Staner along with fourteen known compounds from the fruits and roots. Leplaeric acid E, leplazarin and 21-epileplazarin, 15-α-hydroxy-3,4- seco -lanosta-4(28),8,24-triene-3,21-dioic acid, mayomlactones A and B, lanosta-7,24-dien-3-one, leplaeric acid A, B and C were screened in vitro for antiplasmodial activity against chloroquine-sensitive (Pf3D7) and chloroquine-resistant (PfINDO) strains of Plasmodium falciparum and for cytotoxicity against CAL-27, CaCo2, Skov-3, and HepG2 cells line. Three compounds including 15-α-hydroxy-3,4- seco -lanosta-4(28),8,24-triene-3,21-dioic acid (IC 50 5.65–7.09 μM), lanosta-7,24-dien-3-one (IC 50 7.18–9.07 μM), and leplaeric acid C (IC 50 7.59–8.47 μM) were the most active against both strains of P. falciparum. All the compounds exhibited cytotoxicity against the three-cell lines with IC 50 ranging from 12.30 to 181.88 μM. These results confirm the usage of the medicinal plant L. mayombensis for the management of malaria and suggest that further lead optimization studies on potent compounds identified from this study could lead to the identification of potential of lead molecules as scaffold for new antimalarial drug discovery. [Display omitted] • Three new terpenes and fourteen known compounds were isolated from Leplaea mayombensis. • Compound 5, 6a and 6b are new 3,4-seco-lanostane type triterpenoids. • Antiplasmodial activity and cytotoxicity of all compounds were assessed in vitro. • Compounds 7, 14 and 17 exhibit antiplasmodial activity with IC50 < 10 µM and all the compounds exhibited cytotoxicity. [ABSTRACT FROM AUTHOR]

Published
2022
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20. Physiological Evaluation of Anomalous Aortic Origin of a Coronary Artery Using Computed Tomography–Derived Fractional Flow Reserve

Author

Adjedj, Julien, primary, Hyafil, Fabien, additional, Halna du Fretay, Xavier, additional, Dupouy, Patrick, additional, Juliard, Jean‐Michel, additional, Ou, Phalla, additional, Laissy, Jean‐Pierre, additional, Muller, Olivier, additional, Wijns, William, additional, Aubry, Pierre, additional, Abi Khalil, W., additional, Aguirre, L., additional, Akesbi, A., additional, Aubry, P., additional, Banus, Y., additional, Belle, L., additional, Benamer, H., additional, Biron, Y., additional, Boiffard, E., additional, Bouallal, R., additional, Boudvillain, O., additional, Bourkaïb, R., additional, Brasselet, C., additional, Bressollette, E., additional, Brunel, P., additional, Champagnac, D., additional, Coco, M., additional, Commeau, P., additional, Cook, S., additional, Couppie, P., additional, de Poli, F., additional, Delorme, L., additional, Descoutures, F., additional, Didier, R., additional, Ducrocq, G., additional, Dupouy, P., additional, Durier, C., additional, El Mahmoud, R., additional, Estève, J.‐B., additional, Faurie, B., additional, Garbarz, E., additional, Georges, J.‐L., additional, Gérardin, B., additional, Gibault‐Genty, G., additional, Gilard, M., additional, Godin, M., additional, Goy, J.‐J., additional, Haffner‐Debus, C., additional, Halna du Fretay, X., additional, Hanssen, M., additional, Hascoët, S., additional, Jacquemin, L., additional, Jeanneteau, J., additional, Joseph, T., additional, Juliard, J.‐M., additional, Karsenty, B., additional, Koning, R., additional, La Scala, E., additional, Leddet, P., additional, Lemesle, G., additional, Leurent, G., additional, Levy, R., additional, Livarek, B., additional, Loubeyre, C., additional, Maillard, L., additional, Mangin, L., additional, Marlière, S., additional, Nejjari, M., additional, Ohlmann, P., additional, Poulos, N., additional, Py, A., additional, Ranc, S., additional, Rialan, A., additional, Roriz, R., additional, Rougier, P., additional, Staat, P., additional, Thuaire, C., additional, Togni, M., additional, van Rothem, J., additional, Varenne, O., additional, and Voudris, V., additional

Published
2021
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22. The value of cardiac magnetic resonance imaging in the diagnosis of myocardial infarction with non-occlusive coronary artery: The CRIMINAL prospective registry

Author

Dagrenat, C., primary, Belle, L., additional, Range, G., additional, Georges, J.L., additional, Nallet, O., additional, Delarche, N., additional, Ferrier, N., additional, Ketata, N., additional, Melay, M., additional, Rischner, J., additional, Clerc, J., additional, Naoum Nehmé, E., additional, Boge, A., additional, Barbou, F., additional, Jeannot, C., additional, Delaunay, R., additional, Michel, L., additional, Madiot, H., additional, Couppie, P., additional, and Leddet, P., additional

Published
2021
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23. Residual systemic inflammatory burden is a major determinant of myocardial recovery and late cardiovascular outcome in Takotsubo patients

Author

Lachmet-Thébaud, L., primary, Marchandot, B., additional, Matsushita, K., additional, Sato, C., additional, Dagrenat, C., additional, Greciano, S., additional, De Poli, F., additional, Leddet, P., additional, Carmona, A., additional, Jimenez, C., additional, Heger, J., additional, Reydel, A., additional, Ohlmann, P., additional, Jesel, L., additional, and Morel, O., additional

Published
2021
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26. Incomplete recovery of takotsubo cardiomyopathy is a major determinant of cardiovascular mortality

Author

Matsushita, K, primary, Lachmet-Thebaud, L, additional, Marchandot, B, additional, Sato, C, additional, Dagrenat, C, additional, Greciano, S, additional, De Poli, F, additional, Leddet, P, additional, Trimaille, A, additional, Heger, J, additional, Reydel, A, additional, Trinh, A, additional, Ohlmann, P, additional, Jesel, L, additional, and Morel, O, additional

Published
2020
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27. Residual inflammation is a major determinant of myocardial recovery and cardiovascular outcome in takotsubo patients

Author

Lachmet-Thebaud, L, primary, Marchandot, B, additional, Matsushita, K, additional, Sato, C, additional, Dagrenat, C, additional, Greciano, S, additional, De Poli, F, additional, Leddet, P, additional, Peillex, M, additional, Hess, S, additional, Carmona, A, additional, Reydel, A, additional, Ohlmann, P, additional, Jesel, L, additional, and Morel, O, additional

Published
2020
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29. Risk of stent thrombosis in patients with short (3 months) DAPT after primary PCI with a biodegradable polymer sirolimus-eluting stent: BIOFLOW III/3 French Satellite substudy

Author

Ispas, A., primary, Georges, J.L., additional, Albert, F., additional, Pansieri, M., additional, Delaunay, R., additional, Boueri, Z., additional, Delarche, N., additional, Abdellaoui, M., additional, Dubreuil, O., additional, Leddet, P., additional, and Belle, L., additional

Published
2019
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30. Comparison of Clinical Diagnoses and Rimland E2 Scores in Severely Disturbed Children.

Author

Leddet, I.

Abstract

The Rimland E2 questionnaire was applied to three groups of children diagnosed with Infantile Autism, Autism with Associated Symptoms, and Mental Retardation, as well as normal controls. Results confirmed that the scale accurately differentiates autistic from nonautistic children, but it may not permit clear differentiation of infantile autism from autism with associated symptoms. (Author/CL)

Published
1986

33. Paradoxical Increase of Stroke in Patients with Defect of High Molecular Weight Multimers of the von Willebrand Factors following Transcatheter Aortic Valve Replacement

Author

Matsushita, Kensuke, Marchandot, Benjamin, Trimaille, Antonin, Kibler, Marion, Heger, Joe, Peillex, Marilou, Hess, Sebastien, Grunebaum, Lelia, Reydel, Antje, Kindo, Michel, Hoang, Minh Tam, Sato, Chisato, De Poli, Fabien, Leddet, Pierre, Ohana, Mickael, Jesel, Laurence, Ohlmann, Patrick, Susen, Sophie, and Morel, Olivier

Published
2020
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38. Radial versus femoral access for coronary angiography and intervention is associated with lower patient radiation exposure in high-radial-volume centres: Insights from the RAY’ACT-1 study.

Author

Georges, Jean-Louis, Belle, Loic, Meunier, Ludovic, Dechery, Thierry, Khalifé, Khalifé, Pecheux, Max, Elhaddad, Simon, Amabile, Nicolas, Pansieri, Michel, Ballout, Jacques, Marchand, Xavier, Rouault, Gilles, Leddet, Pierre, Nugue, Olivier, Lucke, Nicolas, and Cattan, Simon

Abstract

Copyright of Archives of Cardiovascular Diseases is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2017
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40. CT-ADP Point-of-Care Assay Predicts 30-Day Paravalvular Aortic Regurgitation and Bleeding Events following Transcatheter Aortic Valve Replacement

Author

Kibler, Marion, Marchandot, Benjamin, Messas, Nathan, Caspar, Thibault, Vincent, Flavien, Von Hunolstein, Jean-Jacques, Grunebaum, Lelia, Reydel, Antje, Rauch, Antoine, Crimizade, Ulun, Kindo, Michel, Hoang Minh, Tam, Trinh, Annie, Petit-Eisenmann, Hélène, De Poli, Fabien, Leddet, Pierre, Jesel, Laurence, Ohlmann, Patrick, Susen, Sophie, Van Belle, Eric, and Morel, Olivier

Published
2018
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42. Prevalence of high and very high radiation doses to patients during percutaneous coronary interventions

Author

Georges, J.-L., primary, Belle, L., additional, Orion, L., additional, Elhadad, S., additional, Marcaggi, X., additional, Funck, F., additional, Vinchon, F., additional, Maccia, C., additional, Livarek, B., additional, Lucke, N., additional, Carrères, T., additional, Montely, J.-M., additional, Schaad, F., additional, Nugue, O., additional, Faure, J.-P., additional, Albert, F., additional, Faltot, H., additional, Karrillon, G., additional, Leddet, P., additional, Schiano, P., additional, Dibie, A., additional, Meunier, L., additional, Perron, J.-M., additional, Marchand, X., additional, Chalet, Y., additional, Genet, L., additional, Azowa, J.-B., additional, and Cattan, S., additional

Published
2013
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43. Management of Takotsubo cardiomyopathy in non-academic hospitals in France: The Observational French SyndromEs of TakoTsubo (OFSETT) study.

Author

Yayehd, Komlavi, N’da, N’kenon W., Belle, Loïc, Bataille, Vincent, Hanssen, Michel, Leddet, Pierre, Aupetit, Jean-François, Commeau, Philippe, Filippi, Emmanuelle, Georges, Jean-Louis, Albert, Franck, Rangé, Grégoire, Meimoun, Patrick, Marcaggi, Xavier, Baleynaud, Serge, Nallet, Olivier, Dibie, Alain, Barnay, Claude, Jouve, Bernard, and Legrand, Maud

Abstract

Copyright of Archives of Cardiovascular Diseases is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2016
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44. Temporal trends of reference levels for radiation doses to patients undergoing coronary angiography and percutaneous coronary interventions. The RAY’ACT study

Author

Georges, J.-L., primary, Jouve, B., additional, Goube, P., additional, Nugue, O., additional, Thuaire, C., additional, Carrères, T., additional, Pansieri, M., additional, Leddet, P., additional, Elhadad, S., additional, Vinchon, F., additional, Perron, J.-M., additional, Ballout, J., additional, Funck, F., additional, Wyart, P., additional, Chalet, Y., additional, Genet, L., additional, Marchand, X., additional, Ledain, L., additional, Faure, J.-P., additional, Benamer, H., additional, Rouhault, G., additional, Vilarem, D., additional, Deutsch, P., additional, Colpart, E., additional, Livarek, B., additional, and Hanssen, M., additional

Published
2012
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45. Bioactive Seco-Lanostane-Type Triterpenoids from the Roots of Leplaea mayombensis

Author

Sidjui, Lazare S., Eyong, Kenneth O., Hull, Kenneth G., Folefoc, Gabriel N., Leddet, Valérie M., Herbette, Gaëtan, Ollivier, Evelyne, Taube, Joseph, Klausmeyer, Kevin, and Romo, Daniel

Abstract

Fractionation of the ethyl acetate-soluble extract of the roots of Leplaea mayombensisafforded two new 3,4-seco-lanostane-type triterpenoids, leplaeric acids A and B (1, 2), the new lanostane-type triterpenoid leplaeric acid C (3), and six known natural products (5–10). Derivatization of the main constituent, 1, afforded the dimethyl ester 4, the monoamide 11, and diamide 12for SAR studies. The structures of these compounds were established through spectroscopic methods, and a single-crystal X-ray diffraction analysis was used to confirm the relative configuration of compound 1. These lanostane derivatives are unique since they are the first C-21-oxygenated lanostanes isolated from plant sources. Preliminary biological assays against the MDA MB 231 breast cancer cell line showed that compounds 1, 2, 4, and 11have modest cytotoxic activity. Compound 2was the most active, with an IC50of 55 ± 7 μM. From these results, the amides (11, 12) derived from triterpenoid 1were found to be less active than the derived esters (2, 4).

Published
2017
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46. Behavioral avoidance and biological safety of vetiver oil and its constituents against Aedes aegypti(L.), Aedes albopictus(Skuse) and Culex quinquefasciatusSay

Author

Nararak, Jirod, Giorgio, Carole Di, Thanispong, Kanutcharee, Sukkanon, Chutipong, Sanguanpong, Unchalee, Mahiou-Leddet, Valerie, Ollivier, Evelyne, Chareonviriyaphap, Theeraphap, and Manguin, Sylvie

Abstract

•Vetiver oil, valencene, and vetiverol had stronger repellent and irritant effects than the other constituents.•Cx. quinquefasciatus was more sensitive to vetiver oil and their constituents than Ae. aegypti and Ae. albopictus.•Vetiver oil and their constituents did not show any phototoxic activity.•None of the tested vetiver oil and their constituents induced a significant increase of micronucleated cells with or without metabolic activation.•Vetiver oil and two constituents (valencene and vetiverol) could be considered as a safe repellent, effective against mosquitoes.

Published
2022
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47. R?ponse de la vigne (Vitis vinifera L) aux temp?ratures inf?rieures ? 0?C. III. Effets d'un refroidissement contr?l? sur des bourgeons au cours du d?bourrement

Author

Dereuddre, J., Audran, JC, Leddet, C., Ait Barka, E., and Brun, O.

Abstract

L'?volution du profil de cristallisation des bourgeons latents d'un c?page champenois a ?t? suivie en analyse thermique diff?rentielle de novembre 1987 ? mai 1988. De novembre ? d?but mars, le profil exothermique des bourgeons en repos v?g?tatif (stade 1) est stable et appara?t toujours compos? de 3 pics. ? partir de la mi-mars, alors qu'aucune modification morphologique du bourgeon n'est d?celable, les temp?ratures d'initiation des 3 pics s'?l?vent. Au stade 2, montrant les premiers signes visibles d'une reprise de croissance du bourgeon, le troisi?me exotherme dispara?t. Du stade 3 au stade 9, marqu?s par la croissance du bourgeon primaire, la remont?e progressive de la temp?rature d'apparition des 2 exothermes suit l'?volution du stade ph?nologique. Cette ?l?vation des temp?ratures de cristallisation se poursuit jusqu'au stade 9, lorsque le deuxi?me exotherme fusionne presque avec le premier. Au stade 2, seul le bourgeon primaire est affect? par le gel. La nature et l'intensit? des d?g?ts varient ensuite en fonction du stade ph?nologique. Les d?chirures tissulaires qui apparaissent perturbent profond?ment l'anatomie des bourgeons, dont la vascularisation est d?sorganis?e. L'apex et les primordia inflorescentiels sont n?cros?s. Analysis of the response of grapevine buds to controlled freezing. The response of latent grapevine buds (Vitis vinifera L cv Chardonnay) from a Champagne vineyard was studied by means of differential thermal analysis from November 1987 to May 1988. During the rest period between November 1987 and March 15th, freezing thermograms (1?C/min) displayed 3 crystallization peaks (E1, E2and E3) as previously described (fig 1). On and after the 15th of March, before any apparent morphological change in the bud, the freezing point (first exotherm) and starting temperatures of the 2 last exotherms (E2and E3) increased progressively. At stage 2, corresponding to the swelling of the bud according to Eichhorn and Lorenz terminology, the starting temperature of the third exotherm increased, leading to the merging of the 2 peaks E1and E2: the thermograms displayed only 2 crystallization peaks. From stage 3 to stage 9 which corresponded to rapid elongation of the shoot and to growth of the leaf and inflorescence, the starting temperatures of the 2 remaining peaks continued to increase. This evolution, which was related to phenological stages, affected the second crystallization peak and led to the fusion of the 2 peaks: freezing thermograms at the end of the growth recovery period only displayed 1 exotherm. At stage 2, the first exotherm induced irreversible histological alterations in the main bud, whereas histological organization of the axillary bud remained apparently unaltered. At stage 5, which was particularly studied in this work, destruction affected every tissue: bark (fig 2), xylem and liber (fig 3), meristematic tissues of the apical dome (fig 4), and the leaf and inflorescence (fig 5).

Published
1993
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48. R?ponse de la vigne ( Vitis vinifera L) aux temp?ratures inf?rieures ? 0?C. II. Effets d'un refroidissement contr?l? sur des bourgeons latents avant le d?bourrement

Author

Leddet, C., Audran, JC, Dereuddre, J., Ait Barka, E., and Brun, O.

Abstract

Des bourgeons latents de vigne (Vitis vinifera L cv Chardonnay) soumis ? un refroidissement progressif (1?C?min-1) entre +5?C et -50?C et ?tudi?s en analyse thermique pr?sentent un profil de cristallisation constitu? de 3 exothermes successifs. Le premier se situe vers -12,9?C, le second, plus important, vers -17,0?C et le troisi?me, plus ?tendu, vers -21,4?C. ? l'?chelle histologique, les observations r?alis?es en microscopie photonique montrent que les cristallisations affectent successivement les tissus de la base du bourgeon (1erexotherme), ceux du bourgeon primaire (2eexotherme) et enfin ceux du bourgeon secondaire (3eexotherme). Analysis of the response of grapevine latent buds to controlled freezing. The effects of controlled freezing on latent grapevine buds (Vitis vinifera L Chardonnay) were studied by means of differential scanning micro-calorimetry and histological techniques. Buds were excised from shoots taken from plants in a Champagne vineyard and frozen progressively from + 5?C to -50?C (1 ?C/min). Figure 1 presents a simplified scheme of the organization of a latent bud. Each bud includes a primary bud with a secondary and eventually a tertiary bud. Thermograms of an entire bud (fig 2A) generally display 3 exotherms at ? -12.9, -17.0?C and -21.4?C. Exothermic peaks obtained during programmed freezing of different parts of the buds differed markedly. Bud scales (fig 2B) showed no exotherm. Two exotherms at -18.2?C and -26?C respectively were obtained when the bud was devoid of its basal part (fig 2C), whereas the 2 peaks of the basal part of the bud occurred at -13.3 and -20?C (fig 2D). When the principal and the secondary buds were frozen separately without their basal parts, they presented only 1 crystallization peak which occurred 3.2 degrees higher in the main bud than in the axillary bud (fig 2E, F). The first exotherm induced histological alterations in the pith of the basal part of the bud (figs 3-5). The second exotherm induced some ruptures of the cell wall (fig 6) and an extension of the cytoplasm contraction to the cells through the basal third of the pith; the other parts of the bud remained apparently intact (fig 7). The third exotherm produced irreversible alterations throughout the main bud (figs 8-11), whereas the meristematic cells seemed to remain intact (fig 12).

Published
1993
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49. R?ponse de la vigne (Vitis vinifera L) aux temp?ratures inf?rieures ? 0?C. I. Effets d'un refroidissement contr?l? sur des sarments ao?t?s

Author

Audran, JC, Leddet, C., Dereuddre, J., Ait Barka, E., and Brun, O.

Abstract

Afin de simuler les effets d'un froid hivernal, des fragments de sarments ao?t?s de vigne ont ?t? soumis artificiellement ? un refroidissement programm? de 1?C.mm-1, entre +5? et -50?C. Les thermogrammes obtenus en microcalorim?trie diff?rentielle ? balayage pr?sentent 2 exothermes successifs : le premier, nettement marqu? vers -9?C, le second, plus ?tal?, d?bute vers -17?C et persiste jusqu'? -30?C. Corr?lativement ? ces pics de cristallisation les analyses histo-cytologiques ont montr? des seuils thermiques de d?gradation s?lective des diff?rents tissus caulinaires : parenchyme cortical et vaisseaux conducteurs du bois (-10?C), liber (-17?C) et cellules m?dullaires (-30?C). Analysis of the response of grapevine mature shoots to controlled freezing. The effects of controlled freezing on mature shoots of grapevine (Vitis vinifera L cv Chardonnay) were studied by differential scanning microcalorimetry and histological techniques. One-yr-old shoots were taken from plants in a Champagne vineyard and frozen progressively from +5?C to -50?C (1?C/min). Figure 1 presents thermograms obtained from different parts of the shoot. Thermograms generally displayed 2 exotherms at ? -10?C and -17?C respectively, whatever the nature of the explant: a piece of shoot, bark or pith. However, secondary xylem thermograms presented only 1 crystallization peak. Histological alterations due to the formation of ice appeared after the first exotherm and involved the bark (figs 2, 3) and the secondary xylem vessels (figs 9, 10 and 11), whereas other tissues (the cambium and liber) remained unaltered (fig 6). After the second exotherm (between -17 and -30?C) every tissue was affected: the bark (fig 4), the liber and cambium (figs 5, 7 and 8), and the secondary xylem (fig 12). In conclusion, although some destruction inside the shoot seemed to have been induced by freezing at -9?C, it only concerned the superficial tissues and did not affect further development of the plant. Further freezing < -17?C appeared necessary to destroy liber and secondary xylem vessels.

Published
1993
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