Publications

2006

• Chiroptical effects in the second harmonic generation from collagens I and IV: applications in nonlinear microscopy
  
  • Pena Ana-Maria
  • Boulesteix Thierry
  • Dartigalongue Thibault
  • Strupler Mathias
  • Beaurepaire Emmanuel
  • Schanne-Klein Marie-Claire
  Nonlinear optics, quantum optics, Old City Pub., 2006, 35 (1-3), pp.235-240. An emerging application of multiphoton microscopy is the observation of unstained intact biological tissues based on intrinsic sources of nonlinear signals. However, reliable biomedical imaging requires a thorough analysis of these endogenous signals. Looking at skin biopsies, we focused on 2-Photon Excited Fluorescence (2PEF) arising from cytokeratins in the epidermis, and second harmonic generation (SHG) from collagen fibers in the dermis. We determined the 2PEF excitation spectrum and action cross section of purified keratins from human epidermis, and obtained a good agreement with in situ measurements. In order to analyze the role of chirality and collagen type in SHG signal, we performed polarization-resolved surface SHG experiments on thin films of collagens I and IV molecules. We observed that collagen I and IV molecules exhibit comparable SHG signals, except for the chiral contributions which are absent for collagen IV and represent typically 50% of the signal for collagen I. We concluded that the large collagen I SHG efficiency is dominated by coherent effects due to the high density and quasi-crystalline order in collagen fibrils, whereas the lack of any alignment within the collagen IV molecules explains the absence of signal from this collagen type in SHG microscopy.
• Molécules d'origine naturelle et nouveaux médicaments anticancéreux [Molecules of natural origin and new anticancer drugs]
  
  • Pages N.
  • Goudey-Perriere Françoise
  • Sauviat Martin-Pierre
  • Benoit Evelyne
  • Chamorro G.
  , 2006, pp.89-98.
• Role of distal arginine in early sensing intermediates in the heme domain of the oxygen sensor FixL
  
  • Jasaitis Audrius
  • Hola Klara
  • Bouzhir-Sima Latifa
  • Lambry Jean-Christophe
  • Balland Véronique
  • Vos Marten H.
  • Liebl Ursula
  Biochemistry, American Chemical Society, 2006, 45, pp.6018-6026.
• Role of Heme Iron Coordination and Protein Structure in the Dynamics and Geminate Rebinding of Nitric Oxide to H93G Myoglobin : Implications for NO-Sensors
  
  • Négrerie Michel
  • Kruglik Sergei
  • Lambry Jean-Christophe
  • Vos Marten H.
  • Martin Jean-Louis
  • Franzen Stefan
  Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2006, 281, pp.10389-10398.
• Functional implications of the propionate 7 Arginine 220 interaction in the FixLH oxygen sensor from Bradyrhizobium japonicum
  
  • Balland Véronique
  • Bouzhir-Sima Latifa
  • Anxolabéhère-Mallart E.
  • Boussac A.
  • Vos Marten H.
  • Liebl Ursula
  • Mattioli T.
  Biochemistry, American Chemical Society, 2006, 45, pp.2072-2084.
• Terahertz achromatic quarter-wave plate
  
  • Masson Jean-Baptiste
  • Gallot Guilhem
  Optics Letters, Optical Society of America - OSA Publishing, 2006, 31 (2), pp.265. Phase retardera usually present a strong frequency dependence. We discuss the design and characterization of a terahertz achromatic quarter-wave plate. This wave plate is made from six birefringent quartz plates precisely designed and stacked together. Phase retardation has been measured over the whole terahertz range by terahertz polarimetry. This achromatic wave plate demonstrates a huge frequency bandwidth (?max/?min ˜ 7), and therefore can be applied to terahertz time domain spectroscopy and polarimetry. Cop. 2006 Optical Society of America. (10.1364/OL.31.000265)
  DOI : 10.1364/OL.31.000265
• Observer les neurones grâce aux ondes térahertz
  
  • Gallot Guilhem
  La Recherche, Sciences et avenir, 2006, 397, pp.26. Des chercheurs de l'École polytechnique ont développé un dispositif d'imagerie des neurones, fondée sur l'utilisation d'ondes térahertz [1]. Ils observent ainsi les mouvements d'ions et d'eau à l'intérieur et à proximité des neurones.
• Evaluation of 23S rRNA PCR primers for use in phylogenetic studies of bacterial diversity
  
  • Hunt D.E.
  • Klepac-Ceraj V.
  • Acinas S.G.
  • Bertilsson S.
  • Gautier Christian
  • Polz M.F.
  Applied and Environmental Microbiology, American Society for Microbiology, 2006, 72 (3), pp.2221. The availability of a diverse set of 23S rRNA gene sequences enabled evaluation of the specificity of 39 previously published and 4 newly designed primers specific for bacteria. An extensive clone library constructed using an optimized primer pair resulted in similar gene richness but slightly differing coverage of some phylogenetic groups, compared to a 16S rRNA gene library from the same environmental sample. Copyright Cop. 2006, American Society for Microbiology. All Rights Reserved. (10.1128/AEM.72.3.2221-2225.2006)
  DOI : 10.1128/AEM.72.3.2221-2225.2006
• Micrometer scale ex vivo multiphoton imaging of unstained arterial wall structure
  
  • Boulesteix Thierry
  • Pena Ana-Maria
  • Pagès Nicole
  • Godeau G.
  • Sauviat Martin-Pierre
  • Beaurepaire Emmanuel
  • Schanne-Klein Marie-Claire
  Cytometry Part A, Wiley, 2006, 69A (1), pp.20-26. We characterize the application of multiphoton microscopy to the observation of the extracellular matrix of fresh unstained vessels. Combined two-photon-excited fluorescence (2PEF) and second harmonic generation (SHG) imaging of large arteries reveals the architecture of elastin and collagen fibers in the vessel wall with remarkable specificity. We present elastin/collagen imaging in unstained rat vessels at both micrometer and whole vessel scales, and we characterize the optical properties of rat carotid artery and aorta walls. We apply this method to evidence deleterious effects of residual doses of a pesticide on the vessel wall. This study illustrates the potential of 2PEF/SHG microscopy for pharmacological studies in unlabeled arteries. © 2005 Wiley-Liss, Inc. (10.1002/cyto.a.20196)
  DOI : 10.1002/cyto.a.20196
• A filtering procedure for systematic removal of pump-perturbed polarization artifacts
  
  • Polack Thomas
  Optics Express, Optical Society of America - OSA Publishing, 2006, 14, pp.5823.
• Dynamics of NO rebinding to the heme domain of NO synthase-like proteins from bacterial pathogens
  
  • Gautier Clément
  • Mikula Ivan
  • Nioche P.
  • Martasek P.
  • Raman C.
  • Slama-Schwok Anny
  Nitric Oxide, 2006, à paraître.
• Conformation of the c552:aa3 electron transfer complex in Paracoccus denitrificans studied by EPR on oriented samples
  
  • Lipowski Gérard
  • Liebl Ursula
  • Guigliarelli Bruno
  • Nitschke Wolfgang
  • Schoepp-Cothenet Barbara
  FEBS Letters, Wiley, 2006, 580 (25), pp.5988. The EPR spectral parameters of aa3 oxidase and cyt c552 from Paracoccus denitrificans were studied in purified oxidase and enriched cyt c552. The orientation of the g-tensors of hemes a and c552 were determined on partially ordered membranes, enriched cyt c552 and a c552:aa3 subcomplex. The known correlation of g-tensor to molecular axes in histidine/methionine ligated hemes permits us to position cyt c552 with respect to the parent membrane. Taken together with previous data on the interaction surface between aa3 oxidase and cyt c552, these results allow us to arrive at a single conformation for the c552:aa3 electron transfer complex. Cop. 2006 Federation of European Biochemical Societies. (10.1016/j.febslet.2006.09.038)
  DOI : 10.1016/j.febslet.2006.09.038
• Emission properties and applications of nanostructured luminescent oxide nanoparticles
  
  • Giaume D.
  • Buissette V.
  • Lahlil K.
  • Gacoin T.
  • Boilot J.-P.
  • Casanova Didier
  • Beaurepaire Emmanuel
  • Sauviat Martin-Pierre
  • Alexandrou Antigoni
  Progress in Solid State Chemistry, Elsevier, 2006, 33 (2-4), pp.99. Rare earth doped oxide materials are well known for their numerous applications in light emitting devices. An interesting issue is to study the emission properties of nanoparticles, with the aim to understand the influence of small size and surface effects on the emission processes. These particles could furthermore be used in new applications such as the elaboration of transparent emitting devices or new biological labels. The work presented here concerns highly luminescent rare earth doped yttrium vanadates (YVO4:Eu) and lanthanum phosphate LaPO4:Ce,Tb*xH2O nanoparticles. Simple aqueous colloidal syntheses are used for the elaboration of concentrated colloids based on the progressive decomposition of polymeric precursors at moderate temperature (60-90 °C). Both types of particles exhibit strong emission (quantum yields of 25% and 45% for vanadates and phosphates, respectively), but significantly lower than that for the equivalent bulk materials. The alteration of the emission processes is discussed in terms of surface quenching effects. Improvements are obtained through the elaboration of core/shell nanostructures. Surface derivatization has been achieved through the controlled growth of an organically modified silica shell using a functionalized silane precursor. Two examples are given concerning the applications of those particles. The first one is the elaboration of transparent and highly luminescent thin films, obtained by the dispersion of the functionalized particles in a sol-gel silica matrix. The other one is the use of guanidine functionalized particles as biological labels for the single particle detection of sodium channels in cardiac cells. (10.1016/j.progsolidstchem.2005.11.041)
  DOI : 10.1016/j.progsolidstchem.2005.11.041
• Chirped Molecular Vibration During Photo-Isomerization in Stilbene Derivative in Solution
  
  • Kobayashi T.
  • Colonna Anne
  • Yabushita A.
  • Iwakura I.
  • Tokunaga E.
  , 2006, pp.poster.
• Ionic contrast terahertz time resolved imaging of frog auricular heart muscle electrical activity
  
  • Masson Jean-Baptiste
  • Sauviat Martin-Pierre
  • Gallot Guilhem
  Applied Physics Letters, American Institute of Physics, 2006, 89 (15), pp.153904. The authors demonstrate the direct, noninvasive and time resolved imaging of functional frog auricular fibers by ionic contrast terahertz (ICT) near field microscopy. This technique provides quantitative, time-dependent measurement of ionic flow during auricular muscle electrical activity, and opens the way of direct noninvasive imaging of cardiac activity under stimulation. ICT microscopy technique was associated with full three-dimensional simulation enabling to measure precisely the fiber sizes. This technique coupled to waveguide technology should provide the grounds to development of advanced in vivo ion flux measurement in mammalian hearts, allowing the prediction of heart attack from change in K+ fluxes. Cop. 2006 American Institute of Physics. (10.1063/1.2360931)
  DOI : 10.1063/1.2360931
• Microscopies multiharmoniques pour l'imagerie structurale de tissus intacts [Second- and third-harmonic generation microscopies for the structural imaging of intact tissues]
  
  • Débarre Delphine
  • Pena Ana-Maria
  • Supatto Willy
  • Boulesteix Thierry
  • Strupler Mathias
  • Martin Jean-Louis
  • Sauviat Martin-Pierre
  • Schanne-Klein Marie-Claire
  • Beaurepaire Emmanuel
  Médecine/Sciences, EDP Sciences, 2006, 22 (10), pp.845. Depuis son introduction en 1990, la microscopie de fluorescence excitée à deux photons (Fluo-2P) s'est peu à peu imposée comme une méthode incontournable d'imagerie de tissus intacts à l'échelle sub-cellulaire. En effet, la caractéristique la plus remarquable de la microscopie multiphotonique est de maintenir une résolution tridimensionnelle micrométrique lors de l'observation en profondeur d'un milieu optiquement diffusant. Combinée aux technologies de protéines-fusion (type GFP), cette approche est aujourd'hui utilisée dans de nombreux domaines, notamment en neurophysiologie. Un autre attrait de ce type d'imagerie réside dans l'utilisation possible d'autres phénomènes optiques non linéaires (c'est-à-dire impliquant l'interaction simultanée de plusieurs photons avec une molécule observée) comme source de contraste. Ainsi, les microscopies par génération de second harmonique (GSH) et par génération de troisième harmonique (GTH) permettent également d'observer des milieux complexes et fournissent des informations complémentaires par rapport à l'imagerie de fluorescence. Certaines structures cellulaires ou tissulaires fournissent, en effet, ce type de réponse optique sans nécessiter de marquage exogène. La microscopie GSH permet, par exemple, de détecter le collagène fibrillaire et la microscopie GTH permet d'observer sans marquage le développement embryonnaire de petits organismes. One principal advantage of multiphoton excitation microscopy is that it preserves its three-dimensional micrometer resolution when imaging inside light-scattering samples. For that reason two-photon-excited fluorescence microscopy has become an invaluable tool for cellular imaging in intact tissue, with applications in many fields of physiology. This success has driven increasing interest in other forms of nonlinear microscopy that can provide additional information on cells and tissues, such as second- (SHG) and third- (THG) harmonic generation microscopies. In recent years, significant progress has been made in understanding the contrast mechanisms of these recent methodologies, and high-resolution imaging based on intrinsic sources of signal has been demonstrated in cells and tissues. Harmonic generation exhibits structural rather than chemical specificity and can be obtained from a variety of non-fluorescent samples. SHG is observed specifically in dense, non-centrosymmetric arrangements of polarizable molecules, such as collagen fibrils, myofilaments, and polarized microtubule bundles. SHG imaging is therefore emerging as a novel approach for studying processes such as the physiopathological remodelling of the collagen matrix and myofibrillogenesis in intact tissue. THG does not require a non-centrosymmetric system; however no signal can be obtained from a homogeneous medium. THG imaging therefore provides maps of sub-micrometer heterogeneities (interfaces, inclusions) in unstained samples, and can be used as a general purpose structural imaging tool. Recent studies showed that this technique can be used to image embryo development in small organisms and to characterize the accumulation of large lipid bodies in specialized cells. SHG and THG microscopy both rely on femtosecond laser technology and are easily combined with two-photon microscopy. (10.1051/medsci/20062210845)
  DOI : 10.1051/medsci/20062210845
• Apport des toxines à la chimiothérapie anticancéreuse cytotoxique.
  
  • Pages N.
  • Goudey-Perriere Françoise
  • Sauviat Martin-Pierre
  • Benoit Evelyne
  • Chamorro G.
  , 2006, pp.81-88.
• Comparative ultrafast dynamics of heme-ligand interactions in proteins
  
  • Vos Marten H.
  , 2006, pp.oral.
• Single Lanthanide-doped Oxide Nanoparticles as Donors in Fluorescence Resonance Energy Transfer Experiments
  
  • Casanova Didier
  • Giaume D.
  • Gacoin Thierry
  • Boilot Jean-Pierre
  • Alexandrou Antigoni
  Journal of Physical Chemistry B, American Chemical Society, 2006, 110(39), pp.19264-19270.
• Photoinduced electron transfer from a novel nanotrigger addressed to the NADPH site within the endothelial NO-synthase to the flavin moieties of the protein
  
  • Beaumont Edward
  • Robin Anne-Claire
  • Berka Vladimir
  • Tsai Ah-Lim
  • Blanchard-Desce Mireille
  • Lambry Jean-Christophe
  • Slama-Schwok Anny
  Nitric Oxide: Biology and Chemistry, Elsevier, 2006, 14 (4), pp.14-15. We developed a new selective molecular tool to trigger enzymatic activity in a synchronous manner and monitor the sequence of the kinetic events by ultra-fast transient spectroscopy. Our approach is based on a synthetic nanotrigger addressing a selected site within proteins, namely the conserved NADPH binding site common to many enzymes involved in bioreductive processes [1]. The nanotrigger combines a "docking" subunit responsible for the recognition of NADPH sites within proteins and a "chromophoric" subunit responsive to light excitation and able to transfer electrons to the flavin moieties of proteins. We present the first spectroscopic data on such a nanotrigger [1] in the presence of the reductase domain of the endothelial nitric oxide synthase eNOSred. (10.1016/j.niox.2006.04.050)
  DOI : 10.1016/j.niox.2006.04.050
• Role of the middle residue in the triple tryptophan electron transfer chain of DNA photolyase: ultrafast spectroscopy of a Trp→Phe mutant
  
  • Lukacs Andras
  • Eker A.P.M.
  • Byrdin M.
  • Villette Sandrine
  • Pan J.
  • Brettel K.
  • Vos Marten H.
  Journal of Physical Chemistry B, American Chemical Society, 2006, 110 (32), pp.15654-15658.
• Nouvelle approche des fibroses par microscopie multiphotonique avec génération de second harmonique [New approach of fibrosis by multiphoton microscopy with second harmonic generation]
  
  • Hernest Monica
  • Pena Ana-Maria
  • Strupler Mathias
  • Beaurepaire Emmanuel
  • Martin Jean-Louis
  • Schanne-Klein Marie-Claire
  • Tharaux Pierre-Louis
  Médecine/Sciences, EDP Sciences, 2006, 22 (10), pp.820-821. La fibrose est une réponse adaptative pathologique qui détruit non spécifiquement les tissus. Il s'agit d'un processus universel de réparation des tissus qui survient en réaction à de nombreux types d'agressions telles les contraintes mécaniques, les brûlures, les radiations ionisantes, l'ischémie, l'inflammation. Ces agressions concourent de manière intriquée à la physiopathologie des maladies infectieuses, tumorales ou auto-immunes, de l'hypertension artérielle et des maladies cardio-vasculaires. Le terme de fibrose décrit précisément l'accumulation nouvelle de protéines de la matrice extra-cellulaire selon un arrangement spatial fibrillaire caractéristique. Il s'agit essentiellement de molécules de collagènes de type I et III (voire de type II, V ou XI) synthétisées sous forme de triples hélices elles-mêmes assemblées en fibrilles par les cellules fibroblastiques. L'apparition des collagènes fibrillaires marque un changement qualitatif et quantitatif de composition des collagènes des tissus. Réciproquement, ces changements de la matrice extracellulaire influencent le phénotype des cellules qui y résident. Ainsi dans le rein normal, le collagène de type I n'existe que dans l'adventice artériel. Son apparition au sein des autres structures de cet organe marque une fibrose tubulo-interstitielle qui constitue le meilleur marqueur pronostic défavorable d'une évolution vers l'insuffisance rénale terminale, et ce quelle que soit la maladie causale. Ainsi, comme lors des fibroses compliquant les hépatopathies et les pneumopathies chroniques, les séquelles de brûlures ou d'abrasions cutanées-muqueuses ou encore le remodelage cardiaque et vasculaire, le réarrangement de la géométrie de la matrice extracellulaire altère l'organisation fonctionnelle du tissu considéré. De ce fait, ce processus de réparation a des effets fonctionnels délétères qui constituent un enjeu médical majeur. Les fibrilles de collagène ont des capacités d'auto-assemblage qui sont aussi catalysées et stabilisées ou au contraire empêchées par les enzymes de la matrice extracellulaire. Le développement de la fibrose ou sa régression dépend donc ainsi du bilan des équilibres biologiques de ces mécanismes. Il est donc crucial de caractériser les changements extracellulaires et cellulaires qui font du restutio ad integrum de l'architecture et de la fonction tissulaire un défi biomédical. (10.1051/medsci/20062210820)
  DOI : 10.1051/medsci/20062210820
• Nonlinear microscopy using Second Harmonic Generation from myosin filaments and fibrillar collagens
  
  • Pena Ana-Maria
  • Strupler Mathias
  • Boulesteix Thierry
  • Fabre Aude
  • Hernest Monica
  • Tharaux Pierre-Louis
  • Crestani Bruno
  • Martin Jean-Louis
  • Sauviat Martin-Pierre
  • Beaurepaire Emmanuel
  • Schanne-Klein Marie-Claire
  , 2006.
• Endothelial nitric oxide synthase reduces nitrite anions to NO under anoxia
  
  • Gautier Clément
  • van Faassen E.
  • Mikula I.
  • Martasek P.
  • Slama-Schwok Anny
  Biochemical and Biophysical Research Communications, Elsevier, 2006, 341 (3), pp.816-821. In this work, we demonstrate that endothelial nitric oxide synthase is capable of anoxic reduction of nitrite anions to nitric oxide at physiological pH by absorption and EPR spectroscopy and electrochemical measurements. The nitrite reduction is achieved at the oxygenase domain of the protein and proceeds even in the absence of the tetrahydrobiopterin cofactor. The nitrite pathway increases by sixfold the NO production with respect to the regular arginine pathway under hypoxia, which is largely blocked. Therefore, basal levels of NO release could be sustained by anoxic nitrite reduction. The reaction suggests a new pathway for fast NO delivery under hypoxia, precisely when the vasodilating properties of nitric oxide are most needed. (c) 2006 Elsevier Inc. All rights reserved. (10.1016/j.bbrc.2006.01.031)
  DOI : 10.1016/j.bbrc.2006.01.031
• Mechanisms involved in the swelling of erythrocytes caused by Pacific and Caribbean ciguatoxins
  
  • Sauviat Martin-Pierre
  • Boydron-Le Garrec Raphaële
  • Masson Jean-Baptiste
  • Lewis Richard L.
  • Vernoux Jean-Paul
  • Molgó Jordi
  • Laurent Dominique
  • Benoit Evelyne
  Blood Cells, Molecules and Diseases, Elsevier, 2006, 36(1), pp.1-9. The mechanisms underlying the swelling of frog red blood cells (RBC), induced by Pacific (P-CTX-1) and Caribbean (C-CTX-1) ciguatoxins (CTXs), were investigated by measuring the length, width and surface of their elliptic shape. P-CTX-1 (0.5 to 5 nM) and C-CTX-1 (1 nM) induced RBC swelling within 60 min. The CTXs-induced RBC swelling was blocked by apamin (1 μM) and by Sr2+ (1 mM). P-CTX-1-induced RBC swelling was prevented and inhibited by H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (27 μM), an inhibitor of soluble guanylate cyclase (sGC), and NOS blockade by NG methyl-l-arginine (l-NMA; 10 μM). Cytochalasin D (cytD, 10 μM) increased RBC surface and mimicked CTX effect but did not prevent the P-CTX-1-induced l-NMA-sensitive extra increase. Calculations revealed that P-CTX-1 and cytD increase RBC total surface envelop and volume. These data strongly suggest that the molecular mechanisms underlying CTXs-induced RBC swelling involve the NO pathway by an activation of the inducible NOS, leading to sGC activation which modulates intracellular cGMP and regulates L-type Ca2+ channels. The resulting increase in intracellular Ca2+ content, in turn, disrupts the actin cytoskeleton, which causes a water influx and triggers a Ca2+-activated K+ current through SK2 isoform channels. (10.1016/j.bcmd.2005.10.007)
  DOI : 10.1016/j.bcmd.2005.10.007