Dual innervation may occur in a partially denervated muscle

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Comparative gene expression profiling of olfactory ensheathing cells from olfactory bulb and olfactory mucosa

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Co-transplantation of olfactory ensheathing cells from mucosa and bulb origin enhances functional recovery after peripheral nerve lesion.

Olfactory ensheathing cells (OECs) represent an interesting candidate for cell therapy and could be obtained from olfactory mucosa (OM-OECs) or olfactory bulbs (OB-OECs). Recent reports suggest that, depending on their origin, OECs display different functional properties. We show here the complementary and additive effects of co-transplanting OM-OECs and OB-OECs after lesion of a peripheral nerve. For this, a selective motor denervation of the laryngeal muscles was performed by a section/anastomosis of the recurrent laryngeal nerve (RLN). Two months after surgery, recovery of the laryngeal movements and synkinesis phenonema were analyzed by videolaryngoscopy. To complete these assessments, measure of latency and potential duration were determined by electrophysiological recordings and myelinated nerve fiber profiles were defined based on toluidine blue staining. To explain some of the mechanisms involved, tracking of GFP positive OECs was performed. It appears that transplantation of OM-OECs or OB-OECs displayed opposite abilities to improve functional recovery. Indeed, OM-OECs increased recuperation of laryngeal muscles activities without appropriate functional recovery. In contrast, OB-OECs induced some functional recovery by enhancing axonal regrowth. Importantly, co-transplantation of OM-OECs and OB-OECs supported a major functional recovery, with reduction of synkinesis phenomena. This study is the first which clearly demonstrates the complementary and additive properties of OECs obtained from olfactory mucosa and olfactory bulb to improve functional recovery after transplantation in a nerve lesion model

Isolation, characterization, and genetic profiling of subpopulations of olfactory ensheathing cells from the olfactory bulb

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Inhibition of ADAMTS-4 Expression in Olfactory Ensheathing Cells Enhances Recovery after Transplantation within Spinal Cord Injury

International audienceSpinal cord injury (SCI) induces permanent loss of sensitive and motor functions below the injury level. To date, a wide variety of cells has been used as biotherapies to cure SCI in different animal paradigms. Specifically, olfactory ensheathing cells (OECs) is one of the most promising. Indeed, OECs have been shown to enhance recovery in many animal studies. Moreover, OECs transplantation has been applied to a paraplegic patient and have shown beneficial effects. However, it has been reported that the significant level of recovery varies among different patients. Therefore, it is of primary importance to enhance the regenerative efficiency of OECs for better translations. Recently, it has been shown that inhibiting ADAMTS4 expression in glial cells in vitro increases their synthesis of neurotrophic factors. We hypothesized that the expression of neurotrophic factors secreted by OECs can be increased by the deletion of ADAMTS4. Taking advantage of ADAMTS4-/- mouse line, we produce ADAMTS4 deficient primary OEC cultures and then we investigated their regenerative potential after SCI. By using quantitative polymerase chain reaction, bioluminescence imaging, measurement of locomotor activity, electrophysiological studies, and immunohistochemistry, our results show that ADAMTS4-/- olfactory bulb OEC (bOECs) primary cultures upregulate their trophic factor expression in vitro, and that the transplantation of ADAMTS4-/- bOECs in a severe SCI model increases functional recovery and tissue repair in vivo. Altogether, our study reveals, for the first time, that primary bOEC cultures transplantation can be potentialized by inhibition of the expression of ADAMTS4

Séisme de Martinique, 29 novembre 2007. Rapport du BCSF : synthèse sismologique et étude macrosismique

Martinique is, with Guadeloupe, classified in seismicity zone III (decree n°2007-1467 of October 12, 2007) which is the highest level of seismic hazard for the French territory. From the point of view of intensities, with a maximum intensity of VI-VII, the earthquake of November 29, 2007 is the most important one felt in Martinique since the earthquake of June 8, 1999 (intensity VII). Macro-seismic intensity reached (in order of distance from the epicenter) VI-VII in the communes of Sainte-Marie, La Trinité, Fort-de-France, Le François, Trois Ilets, Le Marin and Sainte-Anne. The analysis of this earthquake mobilized many people, research laboratories and technical centers. The French Central Seismological Office has prepared a report based on the data processed by the Volcanological and Seismological Observatory of Martinique of the IPGP. The macro-seismic data were collected thanks to the survey forms distributed to the town halls and gendarmerie services by the SIDPC of the prefectures of Martinique and Guadeloupe, thanks to the testimonies filed on the BCSF website and thanks to the information collected during the BCSF field survey that took place from December 5 to 11, 2007. The BCSF's mission is to collect data on the earthquakes felt in France, to gather useful information and to facilitate its dissemination to the actors concerned by the seismic risk or conducting studies or research requiring the use of these observations. It is a member of the Transversal Seismicity Action of the Résif research infrastructure (French Seismological and Geodetic Network).La Martinique est, avec la Guadeloupe, classée en zone de sismicité III (décret n°2007-1467 du 12 octobre 2007) qui est le niveau d'aléa sismique le plus élevé pour le territoire français. Du point de vue des intensités, avec une intensité maximale de VI-VII, le séisme du 29 novembre 2007 est le plus important ressenti en Martinique depuis le séisme du 8 juin 1999 (intensité VII). L’intensité macrosismique a atteint (par ordre de distance à l'épicentre) VI-VII dans les communes de Sainte-Marie, La Trinité, Fort-de-France, Le François, Trois Ilets, le Marin et Sainte-Anne. L’analyse de ce séisme a mobilisé de nombreuses personnes, laboratoires de recherche et centres techniques. Le Bureau Central Sismologique Français a élaboré un rapport qui s’est appuyé sur les données traitées par l’Observatoire Volcanologique et Sismologique de Martinique de l’IPGP. Les données macrosismiques ont été collectées grâce aux formulaires d’enquête distribués auprès des mairies et des services de gendarmerie par le SIDPC des préfectures de Martinique et de Guadeloupe, grâce aux témoignages déposés sur le site Internet du BCSF et grâce aux informations recueillies lors de l’enquête BCSF sur le terrain qui s'est déroulée du 5 au 11 décembre 2007. Le BCSF a pour mission de collecter les données sur les séismes ressentis en France, de rassembler les informations utiles et de faciliter leur diffusion vers les acteurs concernés par le risque sismique ou menant des études ou recherches nécessitant l’usage de ces observations. Il est membre de l’Action transverse sismicité de l’infrastructure de recherche Résif (Réseau sismologique et géodésique français)

Histological analyses.

<p>Histological analyses on longitudinal sections were performed for neurofilament (<b>A</b>), GFAP (<b>G</b>), Neurocan (<b>M</b>) and ED1 (<b>T</b>). These analyses reveal that Primary OB, Purified OB and Purified OM OECs increase axonal regrowth (neurofilament) (<b>A</b>), reduce astrocyte reactivity (GFAP) (<b>G</b>) and glial scar formation (Neurocan) (<b>M</b>). At the same time this analysis reveals that OECs transplantations had no influence on monocytes/microglia infiltration (ED1) (<b>T</b>). Typical illustrations, are shown for each group for neurofilament (<b>B–F</b>), GFAP (<b>H–L</b>), neurocan (<b>O–L</b>) and ED1 (<b>U–Y</b>). Md: Medium, OB: Olfactory Bulb, OM: Olfactory Mucosa. Statistical comparisons were performed using a nonparametric test (Kruskal-Wallis). Mean±SEM represents data from 10 rats per group. *: p value<0.05; **: p value<0.01 and ***: p value<0.001.</p

Analysis of electrophysiological activities.

<p>Measurement of cord dorsum potentials (<b>A–C</b>) shows that transplantation of OECs leads to increase potential amplitude from all OECs treated groups at all-time points studied (<b>A–C</b>). Md: Medium, OB: Olfactory Bulb, OM: Olfactory Mucosa. Statistical comparisons were performed using a nonparametric test (Kruskal-Wallis). Mean±SEM represents data from 10 rats per group. *: p value<0.05.</p

Catwalk analysis.

<p>Catwalk analysis reveals that Primary OB, Purified OB and Purified OM animals show a significant higher probability to walk (based of the higher rate of runs succeed). Percentage (%) is based on run succeed or failed during all the time points. Total number of runs succeed and failed are presented for each group. Md: Medium, OB: Olfactory Bulb, OM: Olfactory Mucosa. Statistical comparisons were performed using a Fisher’s exact test.</p>*<p>: p value<0.05;</p>**<p>: p value<0.01,</p>***<p>: p value<0.001 and #: p value<0.05.</p>*<p>represents significant differences between transplanted groups (Primary OB, Purified OB and Purified OM) and Md group.</p>#<p>represents significant difference between Purified OM and Md groups.</p