450 research outputs found
Brain-Derived Neurotrophic Factor Expression and Respiratory Function Improve after Ampakine Treatment in a Mouse Model of Rett Syndrome
Rett syndrome (RTT) is caused by loss-of-function mutations in the gene encoding methyl-CpG-binding protein 2 (MeCP2). Although MeCP2 is thought to act as a transcriptional repressor of brain-derived neurotrophic factor (BDNF), Mecp2 null mice, which develop an RTT-like phenotype, exhibit progressive deficits in BDNF expression. These deficits are particularly significant in the brainstem and nodose cranial sensory ganglia (NGs), structures critical for cardiorespiratory homeostasis, and may be linked to the severe respiratory abnormalities characteristic of RTT. Therefore, the present study used Mecp2 null mice to further define the role of MeCP2 in regulation of BDNF expression and neural function, focusing on NG neurons and respiratory control. We find that mutant neurons express significantly lower levels of BDNF than wild-type cells in vitro, as in vivo, under both depolarizing and nondepolarizing conditions. However, BDNF levels in mutant NG cells can be increased by chronic depolarization in vitro or by treatment of Mecp2 null mice with CX546, an ampakine drug that facilitates activation of glutamatergic AMPA receptors. Ampakine-treated Mecp2 null mice also exhibit marked functional improvement, characterized by restoration of normal breathing frequency and minute volume. These data demonstrate that BDNF expression remains plastic in Mecp2 null mice and raise the possibility that ampakine compounds could be of therapeutic value in the treatment of RTT
Document interpretation using perceptive cycles to build coherent objects. Application to the french cadastral maps
The methodology we have used for the interpretation of the French cadastral
documents focuses on a number of studied results of the visual perception and a
hierarchical description of the document. The strategy used has been based on the
« model » document, employing a mixed approach including various « points of
view » about the image to be processed.
The results of this mixed analysis reveal the appearance of non-interpretable
objects on the cadasrer, due to the presence of incoherent semantics. Thanks to
the return cycles between the high and low level processing, an analytical strategy
is proposed and allows, in order to independently cure the incoherence, thus to
attain the most reliable interpretation of the cadastral map.Notre méthodologie d'interprétation des documents cadastraux français s'appuie sur un certain nombre de résultats d'études sur la perception visuelle ainsi que sur une description hiérarchisée du document. La stratégie utilisée, basée sur le « modèle » du document, repose sur une approche mixte comportant différents « points de vue » de l'image à traiter. Les résultats de cette analyse mixte mettent en évidence l'apparition d'objets non interprétables au sens du cadastre, du fait de la présence d'incohérences sémantiques. Une stratégie d'analyse est alors proposée et permet, grâce à des cycles d'aller-retours entre les traitements hauts et bas niveaux, de résoudre les incohérences de façon autonome, ceci afin d'interpréter au plus sûr la planche cadastrale
Concept lattices : a tool for primitives selection ?
In this paper, we present the problem of noisy images recognition and in particular the stage of primitives selection in a
classification process. This selection stage appears after segmentation and statistical describers extraction on
documentary images are realized. We describe precisely the use of decision tree in order to harmonize and compare it
with another less studied method based on a concept lattice.Dans ce papier, nous présentons la problématique de la reconnaissance d'images détériorées et plus
particulièrement l'étape de sélection de primitives au sein d'un traitement de classification supervisée. Cette
étape de sélection a lieu après que la segmentation et l'extraction des descripteurs statistiques sur des
images documentaires aient été réalisées. Nous exposons en détail l'utilisation d'un arbre de décision, afin de
l'harmoniser puis la comparer avec une approche moins étudiée utilisant un treillis de Galois
Early-stage development of novel cyclodextrin-siRNA nanocomplexes allows for successful postnebulization transfection of bronchial epithelial cells.
BACKGROUND: Successful delivery of small interfering RNA (siRNA) to the lungs remains hampered by poor intracellular delivery, vector-mediated cytotoxicity, and an inability to withstand nebulization. Recently, a novel cyclodextrin (CD), SC12CDClickpropylamine, consisting of distinct lipophilic and cationic subunits, has been shown to transfect a number of cell types. However, the suitability of this vector for pulmonary siRNA delivery has not been assessed to date. To address this, a series of high-content analysis (HCA) and postnebulization assays were devised to determine the potential for CD-siRNA delivery to the lungs.
METHODS: SC12CDClickpropylamine-siRNA mass ratios (MRs) were examined for size and zeta potential. In-depth analysis of nanocomplex uptake and toxicity in Calu-3 bronchial epithelial cells was examined using IN Cell(®) HCA assays. Nebulized SC12CDClickpropylamine nanocomplexes were assessed for volumetric median diameter (VMD) and fine particle fraction (FPF) and compared with saline controls. Finally, postnebulization stability was determined by comparing luciferase knockdown elicited by SC12CDClickpropylamine nanocomplexes before and after nebulization.
RESULTS: SC12CDClickpropylamine-siRNA complexation formed cationic nanocomplexes of ≤200 nm in size depending on the medium and led to significantly higher levels of siRNA associated with Calu-3 cells compared with RNAiFect-siRNA-treated cells at all MRs (p
CONCLUSIONS: SC12CDClickpropylamine nanocomplexes can be effectively nebulized for pulmonary delivery of siRNA using Aeroneb technology to mediate knockdown in airway cells. To the best of our knowledge, this is the first study examining the suitability of SC12CDClickpropylamine-siRNA nanocomplexes for pulmonary delivery. Furthermore, this work provides an integrated nanomedicine-device combination for future in vitro and in vivo preclinical and clinical studies of inhaled siRNA therapeutics
Tackling the Mouse‐on‐Mouse Problem in Cochlear Immunofluorescence: A Simple Double‐Blocking Protocol for Immunofluorescent Labeling of Murine Cochlear Sections with Primary Mouse Antibodies
The mouse is the most widely used animal model in hearing research. Immunohistochemistry and immunofluorescent staining of murine cochlear sections have, thus, remained a backbone of inner ear research. Since many primary antibodies are raised in mouse, the problem of "mouse-on-mouse" background arises due to the interaction between the anti-mouse secondary antibody and the native mouse immunoglobulins. Here, we describe the pattern of mouse-on-mouse background fluorescence in sections of the postnatal mouse cochlea. Furthermore, we describe a simple double-blocking immunofluorescence protocol to label mouse cochlear cryosections. The protocol contains a conventional blocking step with serum, and an additional blocking step with a commercially available anti-mouse IgG blocking reagent. This blocking technique virtually eliminates the "mouse-on-mouse" background in murine cochlear sections, while adding only a little time to the staining protocol. We provide detailed instructions and practical tips for tissue harvesting, processing, and immunofluorescence-labeling. Further protocol modifications are described, to shorten the duration of the protocol, based on the primary antibody incubation temperature. Finally, we demonstrate examples of immunofluorescence staining performed using different incubation times and various incubation temperatures with a commercially available mouse monoclonal primary antibody
Current status of the Spectrograph System for the SuMIRe/PFS
The Prime Focus Spectrograph (PFS) is a new facility instrument for Subaru
Telescope which will be installed in around 2017. It is a multi-object
spectrograph fed by about 2400 fibers placed at the prime focus covering a
hexagonal field-of-view with 1.35 deg diagonals and capable of simultaneously
obtaining data of spectra with wavelengths ranging from 0.38 um to 1.26 um. The
spectrograph system is composed of four identical modules each receiving the
light from 600 fibers. Each module incorporates three channels covering the
wavelength ranges 0.38-0.65 mu ("Blue"), 0.63-0.97 mu ("Red"), and 0.94-1.26 mu
("NIR") respectively; with resolving power which progresses fairly smoothly
from about 2000 in the blue to about 4000 in the infrared. An additional
spectral mode allows reaching a spectral resolution of 5000 at 0.8mu (red). The
proposed optical design is based on a Schmidt collimator facing three Schmidt
cameras (one per spectral channel). This architecture is very robust, well
known and documented. It allows for high image quality with only few simple
elements (high throughput) at the expense of the central obscuration, which
leads to larger optics. Each module has to be modular in its design to allow
for integration and tests and for its safe transport up to the telescope: this
is the main driver for the mechanical design. In particular, each module will
be firstly fully integrated and validated at LAM (France) before it is shipped
to Hawaii. All sub-assemblies will be indexed on the bench to allow for their
accurate repositioning. This paper will give an overview of the spectrograph
system which has successfully passed the Critical Design Review (CDR) in 2014
March and which is now in the construction phase.Comment: 9 pages, 7 figures, submitted to "Ground-based and Airborne
Instrumentation for Astronomy V, Suzanne K. Ramsay, Ian S. McLean, Hideki
Takami, Editors, Proc. SPIE 9147 (2014)
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