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DOI: 10.3389/fncel.2018.00368
WoS: 000447450500001
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16 Citations

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Résumé:

Dispositif de résonance magnétique nucléaire ou d'imagerie par résonnance magnétique, comportant un système de bobines (1) comportant N paires de bobines (10, 20), où N est un entier supérieur à 1, ces bobines (10, 20) s'étendant au moins partiellement selon une surface enveloppe (E) du système de bobines à symétrie de révolution, chaque bobine (10, 20) comportant au moins deux portions opposées (11, 21) définissant un plan associé (P1, P2) parallèle à un premier plan médian (M) de la surface enveloppe (E) contenant un axe de symétrie (Y) de la surface enveloppe (E), les portions opposées (11, 21) des bobines (10, 20) d'une même paire étant disposées de manière symétrique par rapport au premier plan médian (M), les portions opposées (11, 21) d'une bobine (10, 20) étant disposées de manière symétrique par rapport à un deuxième plan médian (N) contenant ledit axe de symétrie (Y) et perpendiculaire au premier plan médian (M).

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PMID 29877129
DOI: 10.1089/neu.2017.5613
WoS: 000453695000006
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6 Citations
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Spinal cord injuries (SCI) are disastrous neuropathologies causing permanent disabilities. The availability of different strains of mice is valuable for studying the pathophysiological mechanisms involved in SCI. However, strain differences have a profound effect on spontaneous functional recovery after SCI. CX3CR1+/eGFP and Aldh1l1-EGFP mice that express green fluorescent protein in microglia/monocytes and astrocytes, respectively, are particularly useful to study glial reactivity. Whereas CX3CR1+/eGFP mice have C57BL/6 background, Aldh1l1-EGFP are in Swiss Webster background. We first assessed spontaneous functional recovery in CX3CR1+/eGFP and Aldh1l1-EGFP mice over 6 weeks after lateral spinal cord hemisection. Second, we carried out a longitudinal follow-up of lesion evolution using in vivo T2-weighted magnetic resonance imaging (MRI). Finally, we performed in-depth analysis of the spinal cord tissue using ex vivo T2-weighted MRI as well as detailed histology. We demonstrate that CX3CR1+/eGFP mice have improved functional recovery and reduced anxiety after SCI compared with Aldh1l1-EGFP mice. We also found a strong correlation between in vivo MRI, ex vivo MRI, and histological analyses of the injured spinal cord in both strain of mice. All three modalities revealed no difference in lesion extension and volume between the two strains of mice. Importantly, histopathological analysis identified decreased gliosis and increased serotonergic axons in CX3CR1+/eGFP compared with Aldh1l1-EGFP mice following SCI. These results thus suggest that the strain-dependent improved functional recovery after SCI may be linked with reduced gliosis and increased serotonergic innervation.

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DOI: 10.1016/j.pdpdt.2018.02.015
WoS: 000435053900012
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7 Citations
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Here we demonstrate for the first time that Mn2+-doped Prussian blue nanoparticles of c.a. 70 nm act as effective agents for photothermal therapy under two-photon excitation with an almost total eradication of malignant cells (97 and 98%) at a concentration of 100 μg mL−1 24 h after NIR excitation. This effect combined with interesting longitudinal NMR relaxivity values offer new perspectives for effective imaging and cancer treatment.

Commentaires: Highlights• Design of multifunctional nanoparticles able to provide efficient photothermal effect associated with imaging is highly challenging.• New Prussian blue nanoparticles compete with conventional PTT agents in terms of their efficiency and multifunctionality.• We demonstrate that Mn2+-doped Prussian blue nanoparticles act as efficient agents for PTT under two-photon excitation.• These nanoparticles induce an almost total eradication of malignant cells (97 and 98 %) 24 h after NIR excitation.• The combination of PTT with MRI offers new perspectives for efficient cancer treatment with imaging.

Ref HAL: hal-01762923_v1
DOI: 10.5194/jsss-7-227-2018
WoS: 000429154300002
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3 Citations
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Nuclear magnetic resonance (NMR) experiments are usually carried out at very high and homogenous magnetic fields. However, portable systems have emerged in recent years at low fields, offering many advantages like easier maintenance and open design that permit us to imagine a variety of coil configurations in order to maximize the homogeneity of the static field B-0 and the radio-frequency field B-1. The wire winding distribution based on space harmonics suppression (SHS) of the cosine current density distribution offers new possibilities of producing homogenous static fields B-0. In this work, an extension of the SHS method, allowing homogeneity enhancement and flexibility of the coil design, is presented. The efficiency of the method is demonstrated through the construction of homogenous magnetic field coils dedicated to a very low magnetic field (8 mT) H-1 NMR spectrometer. The performance of these coils in terms of magnetic field intensity and homogeneity as well as self-heating behavior is compliant with in planta experiments for agronomic studies.

Ref HAL: hal-01762920_v1
PMID 29596455
DOI: 10.1371/journal.pone.0194845
WoS: 000428630000045
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3 Citations
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The climate warming implies an increase of stress of plants (drought and torrential rainfall). The understanding of plant behavior, in this context, takes a major importance and sap flow measurement in plants remains a key issue for plant understanding. Magnetic Resonance Imaging (MRI) which is well known to be a powerful tool to access water quantity can be used to measure moving water. We describe a novel flow-MRI method which takes advantage of inflow slice sensitivity. The method involves the slice selectivity in the context of multi slice spin echo sequence. Two sequences such as a given slice is consecutively inflow and outflow sensitive are performed, offering the possiblility to perform slow flow sensitive imaging in a quite straigthforward way. The method potential is demonstrated by imaging both a slow flow measurement on a test bench (as low as 10 μm.s−1) and the Poiseuille’s profile of xylemian sap flow velocity in the xylematic tissues of a tomato plant stem.