Publications

2009

• Détection de peroxyde d'hydrogène résolue en temps à l'aide de nanoparticules Y(1-x)Eu(x)VO(4) luminescentes : application à la signalisation vasculaire
  
  • Nguyên Thanh-Liêm
  , 2009. Les espèces dérivées de l'oxygène comme le peroxyde d'hydrogène jouent un rôle déterminant dans le bon fonctionnement des cellules en tant que molécule de signalisation dans de nombreux processus cellulaires. Les fortes concentrations pouvant être nocive, la régulation de ces substances est vitale. Leur détection résolue en temps est longtemps restée un défi pour la compréhension des mécanismes cellulaires et l'élaboration de traitements efficaces pour des maladies comme l'hypertension ou l'athérosclérose. Ce travail de thèse a ainsi été consacré au développement d'un nouveau type de capteur de substances oxydantes à base de nanoparticules de va- nadate d'Yttrium dopé par de l'Europium. Ces nanoparticules peuvent être internalisées dans les cellules et permettent une détection temporelle de la concentration en peroxyde d'hydrogène dans un domaine étendu de concentrations (1 μM à 5 mM). Après une calibration préalable, ces nanoparticules ont permis de détecter la production de peroxyde d'hydrogène dans les mécanismes de signalisation dans des cellules musculaires lisses vasculaires de souris liés à l'endothéline-1 et au facteur de croissance dérivé des plaquettes. Cette étude comparative a montré deux dynamiques différentes de la production de peroxyde d'hydrogène. Ces dynamiques distinctes peuvent expliquer au moins partiellement la différence de comportement cellulaire.
• Mécanismes de contraste et contrôle du front d’onde en microscopie non linéaire cohérente
  
  • Olivier Nicolas
  , 2009. This Thesis deals with theoretical and experimental aspects of coherent nonlinear microscopy, with a special attention given to contrast mechanisms in Third Harmonic Generation (THG) microscopy.
• Red Blood Cell Sickling in Microfluidic droplets
  
  • Abbyad Paul
  • Baroud Charles N.
  • Tharaux Pierre-Louis
  • Alexandrou Antigoni
  , 2009.
• Spectroscopie et imagerie térahertz des systèmes d'intérêt biologique.
  
  • Podzorov Alexander
  , 2009. Ce travail de thèse présente quelques exemples d'utilisation du rayonnement térahertz pour l'étude de systèmes d'intérêt biologique. Nous avons construit et caractérisé deux dispositifs expérimentaux analogues, chacun conçu de façon à servir à une famille d'applications particulière. Ces dispositifs sont basés sur la génération et la détection des ondes térahertz à l'aides d'antennes photoconductrices pilotées par un laser infrarouge femtoseconde. Un premier dispositif térahertz, dédié à la spectroscopie dans le domaine temporel, permet de caractériser de nombreux systèmes plus ou moins homogènes du point de vue spectroscopique, c'est-à-dire d'obtenir la permittivité complexe du matériau et sa dépendance spectrale. L'étude des nouveaux matériaux transparents en térahertz et des solutions ioniques aqueuses à l'aide de ce spectromètre térahertz a été accomplie. Un deuxième dispositif est consacré au développement de nouvelles techniques d'imagerie térahertz en champ proche avec ouverture. En effet, un contraste fourni par la différence d'absorption des solutions ioniques a permis d'étudier des cellules biologiques de façon non-invasive ; il s'agit ici notamment de l'embryon de drosophile et du nerf sciatique de grenouille. Le lien entre ces deux thématiques est fait par la recherche sur les plasmons-polaritons de surfaces, des ondes électromagnétiques à la surface de métaux, qui, dans certaines conditions, permettent d'exalter la transmission à travers des ouvertures de taille inférieure à la longueur d'onde. Des études spectroscopiques ont permis de comprendre certaines propriétés fondamentales de ces ondes surfaciques en vue de leur application aux nouvelles sondes de champ proche.
• Dynamic aberration correction for multiharmonic microscopy.
  
  • Olivier Nicolas
  • Débarre Delphine
  • Beaurepaire Emmanuel
  Optics Letters, Optical Society of America - OSA Publishing, 2009, 34 (20), pp.3145-7. We demonstrate image-based aberration correction in a third-harmonic generation (THG) microscope. We describe a robust, mostly sample-independent correction scheme relying on prior measurement of the influence of aberration modes produced by a deformable mirror on the quality of THG images. We find that using image sharpness as an image quality metric, correction of N aberration modes is achieved using 2(2N+1) measurements in a variety of samples. We also report aberration correction in combined multiharmonic and two-photon excited fluorescence experiments. Finally, we demonstrate time-dependent adaptive THG imaging in developing embryonic tissue.
• Beam waist measurement for terahertz time domain experiments
  
  • Gallot Guilhem
  • Podzorov Alexander
  • Wojdyla Antoine
  , 2009, pp.1-2. Classical variable aperture masking method is not directly applicable to Time Domain Spectroscopy (TDS) experiments. Here, we present a simple and reliable method for measuring beam waists in TDS. It is based on the successive diffraction by an opaque disk followed by a small circular aperture. © 2009 IEEE. (10.1109/ICIMW.2009.5325575)
  DOI : 10.1109/ICIMW.2009.5325575
• Hole depth dependence of the extraordinary electromagnetic transmission in the terahertz domain
  
  • Podzorov A.
  • Masson J.-B.
  • Gallot Guilhem
  , 2009, pp.1-2. (10.1109/ICIMW.2009.5324713)
  DOI : 10.1109/ICIMW.2009.5324713
• The crystal structure of ORF14 from Sulfolobus islandicus filamentous virus
  
  • Goulet Adeline
  • Spinelli Silvia
  • Blangy Stéphanie
  • van Tilbeurgh Herman
  • Leulliot Nicolas
  • Basta Tamara
  • Prangishvili David
  • Cambillau Christian
  • Campanacci Valérie
  Proteins - Structure, Function and Bioinformatics, Wiley, 2009, 76 (4), pp.1020-1022. (10.1002/prot.22448)
  DOI : 10.1002/prot.22448
• Concepts to build nonlinear optical biomaterials in a bottom-up approach
  
  • Matar G.
  • Duboisset J.
  • Brevet P.-F.
  • Besson F.
  • Benichou E.
  • Deniset-Besseau Ariane
  • Schanne-Klein Marie-Claire
  , 2009, 7487. We have performed Hyper-Rayleigh Scattering (HRS) experiments to measure the quadratic hyperpolarizability of several natural amino acids, in particular tryptophan and tyrosine. Values of (29.6+/-0.4)x10-30 esu for tryptophan and (25.7+/-0.03)x10-30 esu for tyrosine have been found. We have then investigated the dependence of the quadratic hyperpolarizability of tryptophan-rich short peptides as a function of the number of tryptophans in the sequence. The experimental findings indicate that the resulting quadratic hyperpolarizability in these peptides cannot be assumed as the mere coherent superposition of the hyperpolarizabilities of the tryptophans contained in the peptide. Our results unambiguously demonstrate that there must be strong interactions between the tryptophans contained in these short peptides. We have also investigated the case of the collagen triple helix. A second order hyperpolarizability of (1.25+/- 0.05)x10-27 esu for rat-tail type I collagen has been measured. In this case, we have been able to model this effective quadratic hyperpolarizability by summing coherently the nonlinear response of elementary moieties forming the triple helix, as opposed to the previous case of the tryptophan-rich peptides. © 2009 SPIE. (10.1117/12.834084)
  DOI : 10.1117/12.834084
• Multiplexed two-photon microscopy of dynamic biological samples with shaped broadband pulses.
  
  • Pillai Rajesh S.
  • Boudoux Caroline
  • Labroille Guillaume
  • Olivier Nicolas
  • Veilleux Israel
  • Farge Emmanuel
  • Joffre Manuel
  • Beaurepaire Emmanuel
  Optics Express, Optical Society of America - OSA Publishing, 2009, 17 (15), pp.12741-52. Coherent control can be used to selectively enhance or cancel concurrent multiphoton processes, and has been suggested as a means to achieve nonlinear microscopy of multiple signals. Here we report multiplexed two-photon imaging in vivo with fast pixel rates and micrometer resolution. We control broadband laser pulses with a shaping scheme combining diffraction on an optically-addressed spatial light modulator and a scanning mirror allowing to switch between programmable shapes at kiloHertz rates. Using coherent control of the two-photon excited fluorescence, it was possible to perform selective microscopy of GFP and endogenous fluorescence in developing Drosophila embryos. This study establishes that broadband pulse shaping is a viable means for achieving multiplexed nonlinear imaging of biological tissues. (10.1364/OE.17.012741)
  DOI : 10.1364/OE.17.012741
• Structure and function of a novel endonuclease acting on branched DNA substrates.
  
  • Ren Bin
  • Kühn Joelle
  • Meslet-Cladiere Laurence
  • Briffotaux Julien
  • Norais Cedric
  • Lavigne Regis
  • Flament Didier
  • Ladenstein Rudolf
  • Myllykallio Hannu
  EMBO Journal, EMBO Press, 2009, 28 (16), pp.2479-89. We show that Pyrococcus abyssi PAB2263 (dubbed NucS (nuclease for ss DNA) is a novel archaeal endonuclease that interacts with the replication clamp PCNA. Structural determination of P. abyssi NucS revealed a two-domain dumbbell-like structure that in overall does not resemble any known protein structure. Biochemical and structural studies indicate that NucS orthologues use a non-catalytic ssDNA-binding domain to regulate the cleavage activity at another site, thus resulting into the specific cleavage at double-stranded DNA (dsDNA)/ssDNA junctions on branched DNA substrates. Both 3' and 5' extremities of the ssDNA can be cleaved at the nuclease channel that is too narrow to accommodate duplex DNA. Altogether, our data suggest that NucS proteins constitute a new family of structure-specific DNA endonucleases that are widely distributed in archaea and in bacteria, including Mycobacterium tuberculosis. (10.1038/emboj.2009.192)
  DOI : 10.1038/emboj.2009.192
• Coherent nonlinear microscopy system and method with variation of the focal volume in order to probe the nanostructure of organized materials (extension du dépôt français EP20090769543)
  
  • Beaurepaire Emmanuel
  • Olivier Nicolas
  • Débarre Delphine
  • Schanne-Klein Marie-Claire
  • Martin Jean-Louis
  , 2009. A method for the dimensional characterization of a structured material, in which method: an excitation laser beam suitable for coherent nonlinear microscopy is generated, this excitation laser beam being focused in a focal volume within the structured material; signals emitted by the structured material are detected; a plurality of emission patterns, each corresponding to one particular shape of the focal volume, is produced, the particular shapes being obtained for various non-Gaussian spatial profiles of the excitation laser beam wavefront; and on the basis of the emission patterns thus produced, dimensional characteristics of the structured material are deduced therefrom.
• The assignment of Qy(1,0) vibrational structure and Q x for chlorophyll a
  
  • Hughes Joseph L.
  • Conlon B.
  • Krausz E.
  • Wydrzynski T.
  , 2010, 3 (4), pp.1591. We used non-photochemical persistent spectral hole-burning at 1.4 K to investigate the Qy(1,0) vibrational structure of Chl a in a water-soluble chlorophyll-binding protein (WSCP) which exhibits resolved structure in its broadband optical spectra. Franck-Condon vibrational overlap factors were determined from the vibrational hole-burning data and used to simulate the Qy(1,0) spectra. The simulations were not able to accurately reproduce the details of the Qy(1,0) spectrum. This indicates a breakdown of the approximations used for the analysis and demonstrates that vibrationally induced mixing of electronic states (vibronic coupling) is active for Chl a. By considering the inhomogeneous broadening and vibrational hole-burning phenomena in the Qx and Qy(1,0) region of Chl-WSCP in addition to magnetic circular dichroism data, we favor the traditional placement of Qx at ?~570-590 nm rather than the alternate assignment underneath the Qy(1,0) absorption near ?~615-630 nm. © 2010 Elsevier B.V. All rights reserved. (10.1016/j.phpro.2010.01.226)
  DOI : 10.1016/j.phpro.2010.01.226
• Second order hyperpolarizability of the collagen triple helix: Measurement and determination of its physical origin
  
  • Deniset-Besseau Ariane
  • Duboisset J.
  • Loison Claire
  • Benichou E.
  • Hache François
  • Brevet P.-F.
  • Schanne-Klein Marie-Claire
  , 2009, 2009. Collagen is the major protein of the extracellular matrix and plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. As a fundamental brick of the architecture of tissues, it guarantees organs functioning and is crucial in the adaptative response to various tissue injuries. This protein is characterized by triple helical domains and possesses remarkable non linear optical properties. Indeed, collagen fibers exhibit efficient Second Harmonic Generation (SHG) in tissues and SHG microscopy has proved to be a valuable technique to probe the three-dimensional architecture of fibrillar collagen in native and biomimetic tissues and to assess the progression of fibrotic pathologies. However, the nonlinear optical response of fibrillar collagen is not fully characterized yet and quantitative data are required to further process SHG images. We therefore performed Hyper-Rayleigh Scattering (HRS) experiments in order to measure quantitatively the nonlinear optical response of the collagen molecule, and to get insight into the physical origin of high SHG signals observed for fibrillar collagen in tissues. (10.1109/CLEOE-EQEC.2009.5194760)
  DOI : 10.1109/CLEOE-EQEC.2009.5194760
• The thermo- and acido-stable ORF-99 from the archaeal virus AFV1
  
  • Goulet Adeline
  • Spinelli Silvia
  • Blangy Stéphanie
  • van Tilbeurgh Herman
  • Leulliot Nicolas
  • Basta Tamara
  • Prangishvili David
  • Cambillau Christian
  • Campanacci Valérie
  Protein Science, Wiley, 2009, 18 (6), pp.1316-1320. (10.1002/pro.122)
  DOI : 10.1002/pro.122
• Two-photon microscopy with simultaneous standard and extended depth of field using a tunable acoustic gradient-index lens.
  
  • Olivier Nicolas
  • Mermillod-Blondin Alexandre
  • Arnold Craig B.
  • Beaurepaire Emmanuel
  Optics Letters, Optical Society of America - OSA Publishing, 2009, 34 (11), pp.1684-1686. We describe a simple setup that allows depth of field switching at kilohertz rates in a nonlinear microscope. Beam profile and/or divergence are modulated using a tunable, acoustically driven gradient-index fluid lens. We demonstrate two modulation strategies, one based on fast varifocus scanning during each pixel and the other based on pseudo-Bessel beam excitation. Average beam shape is switched every line during scanning, resulting in the interlaced acquisition of two different images. We apply this approach to the simultaneous standard and 4.5x-extended depth-of-field imaging of developing embryos. © 2009 Optical Society of America (10.1364/OL.34.001684)
  DOI : 10.1364/OL.34.001684
• Procédé et dispositif d'acquisition de signaux en microscopie laser à balayage
  
  • Beaurepaire Emmanuel
  • Veilleux Israel
  • Olivier Nicolas
  • Débarre Delphine
  • Martin Jean-Louis
  , 2009.
• HIV-1 IN alternative molecular recognition of DNA induced by raltegravir resistance mutations
  
  • Mouscadet J.-F.
  • Arora Rakesh
  • André J.
  • Lambry Jean-Christophe
  • Delelis O.
  • Malet I.
  • Marcelin A.-G.
  • Calvez V.
  • Tchertanov L.
  Journal of Molecular Recognition, Wiley, 2009, 22 (6), pp.480-494. Virologic failure during treatment with raltegravir, the first effective drug targeting HIV integrase, is associated with two exclusive pathways involving either Q148H/R/K, G140S/A or N155H mutations. We carried out a detailed analysis of the molecular and structural effects of these mutations. We observed no topological change in the integrase core domain, with conservation of a newly identified V-shaped hairpin containing the Q148 residue, in particular. In contrast, the mutations greatly altered the specificity of DNA recognition by integrase. The native residues displayed a clear preference for adenine, whereas the mutant residues strongly favored pyrimidines. Raltegravir may bind to N155 and/or Q148 residues as an adenine bioisoster. This may account for the selected mutations impairing raltegravir binding while allowing alternative DNA recognition by integrase. This study opens up new opportunities for the design of integrase inhibitors active against raltegravir-resistant viruses. Copyright Cop. 2009 John Wiley and Sons, Ltd. Supporting information may be found in the online version of this article. (10.1002/jmr.970)
  DOI : 10.1002/jmr.970
• NO formation by neuronal NO-synthase can be controlled by ultrafast electron injection from a nanotrigger
  
  • Beaumont Edward
  • Lambry Jean-Christophe
  • Blanchard-Desce M.
  • Martasek P.
  • Panda S.P.
  • van Faassen E.E.H.
  • Brochon J.-C.
  • Deprez E.
  • Slama-Schwok Anny
  ChemBioChem, Wiley-VCH Verlag, 2009, 10 (4), pp.690. Nitric oxide synthases (NOSs) are unique flavohemoproteins with various roles in mammalian physiology. Constitutive NOS catalysis is initiated by fast hydride transfer from NADPH, followed by slower structural rearrangements. We used a photoactive nanotrigger (NT) to study the initial electron transfer to FAD in native neuronal NOS (nNOS) catalysis. Molecular modeling and fluorescence spectroscopy showed that selective NT binding to NADPH sites close to FAD is able to override Phe1395 regulation. Ultrafast injection of electrons into the protein electron pathway by NT photoactivation through the use of a femtosecond laser pulse is thus possible. We show that calmodulin, required for NO synthesis by constitutive NOS, strongly promotes intramolecular electron flow (6.2-fold stimulation) by a mechanism involving proton transfer to the reduced FADb site. Site-directed mutagenesis using the S1176A and S1176T mutants of nNOS supports this hypothesis. The NT synchronized the initiation of flavoenzyme catalysis, leading to the formation of NO, as detected by EPR. This NT is thus promising for time-resolved X-ray and other cellular applications. Cop. 2009 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim. (10.1002/cbic.200800721)
  DOI : 10.1002/cbic.200800721
• Erratum to : Application of time-resolved circular dichroism to the study of conformational changes in photochemical and photobiological processes
  
  • Hache François
  Journal of Photochemistry and Photobiology A: Chemistry, Elsevier, 2009, 205 (1), pp.77. (10.1016/j.jphotochem.2009.05.017)
  DOI : 10.1016/j.jphotochem.2009.05.017
• Picosecond Transient Circular Dichroism of the Photoreceptor Protein of the Light-Adapted Form of Blepharisma Japonicum
  
  • Hache François
  • Khuc Mai-Thu
  • Brazard Johanna
  • Plaza Pascal
  • Martin Monique M.
  • Checcucci Giovanni
  • Lenci Francesco
  Chemical Physics Letters, Elsevier, 2009, 483, pp.133. We present a picosecond transient circular dichroism study of OBIP, the putative photoreceptor protein involved in the photophobic response of Blepharisma Japonicum. The probe wavelength was chosen at 230 nm. The results are compared to those of the isolated chromophore, OxyBP, in solution. The CD changes in OBIP and OxyBP do not show the same dynamics: OBIP's signal relaxes in a few ps whereas no such decay is obtained for OxyBP. This observation brings support to the formerly evoked existence of a fast photoinduced reaction in the chromoprotein, and demonstrates the implication of local geometrical changes that accompany this process. (10.1016/j.cplett.2009.10.059)
  DOI : 10.1016/j.cplett.2009.10.059
• Interaction of carbon monoxide with the apoptosis-inducing cytochrome c-cardiolipin complex
  
  • Kapetanaki Sofia M.
  • Silkstone G.
  • Husu I.
  • Liebl Ursula
  • Wilson M.T.
  • Vos Marten H.
  Biochemistry, American Chemical Society, 2009, 48 (7), pp.1613. The interaction of mitochondrial cytochrome (cyt) c with cardiolipin (CL) is involved in the initial stages of apoptosis. This interaction can lead to destabilization of the heme−Met80 bond and peroxidase activity [Basova, L. V., et al. (2007) Biochemistry 46, 3423−3434]. We show that under these conditions carbon monoxide (CO) binds to cyt c, with very high affinity (5 × 107 M−1), in contrast to the native cyt c protein involved in respiratory electron shuttling that does not bind CO. Binding of CO to the cyt c−CL complex inhibits its peroxidase activity. Photodissociated CO from the cyt c−CL complex shows <20% picosecond geminate rebinding and predominantly bimolecular rebinding, with a second-order rate constant of 107 M−1 s−1, an order of magnitude higher than in myoglobin. These findings contrast with those of Met80X mutant cyt c, where picosecond geminate recombination dominates due to the rigidity of the protein. Our data imply that CL leads to substantial changes in protein conformation and flexibility, allowing access of ligands to the heme. Together with the findings that (a) 30 CL per cyt c are required for full CO binding and (b) salt-induced dissociation indicates that the two negative headgroup charges interact with 5 positive surface charges of the protein, these results are consistent with a CL anchorage model with an acyl chain impaled in the protein [Kalanxhi, E., and Wallace, C. J. A. (2007) Biochem. J. 407, 179−187]. The affinity of CO for the complex is high enough to envisage an antiapoptotic effect of nanomolar CO concentrations via inhibition of the cyt c peroxidase activity. (10.1021/bi801817v)
  DOI : 10.1021/bi801817v
• New insights into size effects in luminescent oxide nanocrystals
  
  • Mialon G.
  • Türkcan Silvan
  • Alexandrou Antigoni
  • Gacoin Thierry
  • Boilot Jean-Pierre
  Journal of Physical Chemistry C, American Chemical Society, 2009, 113 (43), pp.18699. We here investigate the emission properties of rare-earth-doped oxide nanoparticles with the aim to understand the commonly observed altered properties of nanoparticles as compared to the bulk counterparts. This is usually attributed to the detrimental effect of surface states that quench the excited states involved in the emission process. We study the influence of crystalline defects that are present due to the low temperature of the synthesis of 30 nm sized YVO4/Eu nanoparticles. Annealing treatments up to 1000 °C in a porous silica matrix allow the recovery of perfectly crystalline particles as colloidal suspensions and compare their properties to those of the pristine particles obtained by conventional colloid chemistry. Emission properties of pristine and annealed particles are compared with those of the bulk material. A simple model of the emission process allows an accurate fit of the luminescence decay and of the dependence of the quantum yield on europium content. Our results show that pristine particles exhibit altered emission properties mainly due to quenching from defects, among which are surface OH groups, and altered energy transfers within the particle. Annealed particles exhibit properties that are almost the same as those of the bulk material, except that the emission yield for the optimum Eu content is limited to 40 instead of 70% for the bulk material. We show that the difference may be simply explained by the difference of the radiative lifetime that results from the lower effective refractive index in the case of the particles. This effect then seems to be the ultimate limitation for the emission properties of perfectly well-crystallized nanoparticles as compared to those of the bulk material. This work provides an example of a general strategy toward the investigation of the physical properties of nanocrystals which may be altered by crystalline defects. Cop. 2009 American Chemical Society. (10.1021/jp907176x)
  DOI : 10.1021/jp907176x
• Unobtrusive interferometer tracking by path length oscillation for multidimensional spectroscopy
  
  • Lee Kevin F.
  • Bonvalet Adeline
  • Nuernberger Patrick
  • Joffre Manuel
  Optics Express, Optical Society of America - OSA Publishing, 2009, 17 (15), pp.12379-12384. We track the path difference between interferometer arms with few-nanometer accuracy without adding optics to the beam path. We measure the interference of a helium-neon beam that copropagates through the interferometer with midinfrared pulses used for multidimensional spectroscopy. This can indicate motion, but not direction. By oscillating the path length of one arm with a mirror on a piezoelectric stack and monitoring the oscillations of the recombined helium-neon beam, the direction can be calculated, and the path delay can be continuously tracked. © 2009 Optical Society of America. (10.1364/OE.17.012379)
  DOI : 10.1364/OE.17.012379
• Apports récents des techniques de quantification de la fibrose pour l'examen anatomopathologique en transplantation rénale
  
  • Servais A.
  • Meas-Yedid V.
  • Morelon E.
  • Strupler Mathias
  • Schanne-Klein Marie-Claire
  • Legendre C.
  • Olivo-Marin J.-C.
  • Thervet É.
  Médecine/Sciences, EDP Sciences, 2009, 25 (11), pp.945-950. La néphropathie chronique d'allogreffe constitue la cause principale de perte des greffons rénaux à long terme. Elle peut être détectée précocement par des biopsies de dépistage effectuées de manière systématique. La classification usuelle, semi-quantitative, souffre d'une mauvaise reproductibilité. Diverses méthodes morphométriques ont donc été développées pour quantifier la fibrose interstitielle qui caractérise cette néphropathie. Certaines utilisent la coloration spécifique par le rouge Sirius. L'analyse d'image couleur par segmentation permet une quantification automatique, rapide et robuste de la fibrose interstitielle. Elle utilise une segmentation couleur associée à une analyse de couleur, de localisation spatiale et de forme sur des biopsies colorées au trichrome de Masson. À l'avenir, l'étude des collagènes fibrillaires par la génération de second harmonique pourrait permettre une approche spécifique des composants de la fibrose. (10.1051/medsci/20092511945)
  DOI : 10.1051/medsci/20092511945