185 resultados para Deep architecture


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Antiresorptive agents such as bisphosphonates induce a rapid increase of BMD during the 1st year of treatment and a partial maintenance of bone architecture. Trabecular Bone Score (TBS), a new grey-level texture measurement that can be extracted from the DXA image, correlates with 3D parameters of bone micro-architecture. Aim: To evaluate the longitudinal effect of antiresorptive agents on spine BMD and on site-matched spine microarchitecture as assessed by TBS. Methods: From the BMD database for Province of Manitoba, Canada, we selected women age >50 with paired baseline and follow up spine DXA examinations who had not received any prior HRT or other antiresorptive drug.Women were divided in two subgroups: (1) those not receiving any HRT or antiresorptive drug during follow up (=non-users) and (2) those receiving non-HRT antiresorptive drug during follow up (=users) with high adherence (medication possession ratio >75%) from a provincial pharmacy database system. Lumbar spine TBS was derived by the Bone Disease Unit, University of Lausanne, for each spine DXA examination using anonymized files (blinded from clinical parameters and outcomes). Effects of antiresorptive treatment for users and non-users on TBS and BMD at baseline and during mean 3.7 years follow-up were compared. Results were expressed % change per year. Results: 1150 non-users and 534 users met the inclusion criteria. At baseline, users and non-users had a mean age and BMI of [62.2±7.9 vs 66.1±8.0 years] and [26.3±4.7 vs 24.7±4.0 kg/m²] respectively. Antiresorptive drugs received by users were bisphosphonates (86%), raloxifene (10%) and calcitonin (4%). Significant differences in BMD change and TBS change were seen between users and nonusers during follow-up (p<0.0001). Significant decreases in mean BMD and TBS (−0.36± 0.05% per year; −0.31±0.06% per year) were seen for non-users compared with baseline (p<0.001). A significant increase in mean BMD was seen for users compared with baseline (+1.86±0.0% per year, p<0.0018). TBS of users also increased compared with baseline (+0.20±0.08% per year, p<0.001), but more slowly than BMD. Conclusion: We observed a significant increase in spine BMD and a positive maintenance of bone micro-architecture from TBS with antiresorptive treatment, whereas the treatment naïve group lost both density and micro-architecture. TBS seems to be responsive to treatment and could be suitable for monitoring micro-architecture. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: M.-A. Krieg: None declared, A. Goertzen: None declared, W. Leslie: None declared, D. Hans Consulting fees from Medimaps.

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The HeCo mouse model is characterized by a subcortical heterotopia formed by misplaced neurons normally migrating into the superficial cortical layers. The mutant mouse has a tendency to epileptic seizures. In my thesis project we discovered the mutated Eml1 gene, a member of the echinoderm microtubule-associated protein (EMAP) family, in HeCo as well as in a family of three children showing complex malformation of cortical development. This discovery formed an important step in exploring the pathogenic mechanisms underlying the HeCo phenotype. In vitro results showed that during cell division the EML1 protein is associated with the midbody and a mutated version of Eml1 highlighted an important role of the protein in the astral MT array during cell cycle. In vivo, we found that already at an early age of cortical development (E13), ectopic progenitors such as RGs (PAX6) and IPCs (TBR2) accumulate in the IZ along the entire neocortex. We demonstrated that in the VZ of the HeCo mouse, spindle orientation and cell cycle exit are perturbed. In later stages (E17), RG fibers are strongly disorganized with deep layer (TBR1) and upper layer (CUX1) neurons trapped within an ectopic mass. At P3, columns of upper layer neurons were present between the heterotopia and the developing cortex; these columns were also present at P7 but at lesser extent. Time lapse video recording (E15.5) revealed that the parameters characterizing the migration of individual neurons are not disturbed in HeCo; however, this analysis showed that the density of migrating neuron was smaller in HeCo. In conclusion, truncated EML1 is likely to play a prominent role during cell cycle but also acts on the cytoskeletal architecture altering the shape of RG fibers thus influencing the pattern of neuronal migration. The signal transduction between external cues and intracellular effector pathways through MTs may be secondary but sustains the heterotopia development and further studies are needed to clarify the impact of EML1 in progenitors versus post-mitotic cells.

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RAPPORT DE SYNTHESE : BUT : Le but de ce sujet de recherche est d'évaluer le taux de succès et les complications à long terme de la sclérectomie profonde non pénétrante avec implant de collagène (SPIC) chez les patients atteints de glaucome à angle ouvert. METODES ET PATIENTS : Il s'agit d'une étude clinique, prospective, monocentrique, non-randomisée, effectuée sur 105 patients atteints d'un glaucome à angle ouvert médicalement non-contrôlé. Ces patients ont tous bénéficiés d'une SPIC, effectuée selon le geste chirurgicale standard (technique décrite dans l'article). Dans le cadre de cette étude, nous avons effectué un bilan ophtalmologique complet avant l'acte chirurgical puis un suivi postopératoire à 1 et 7 jours ; 1,2,3,6,9,12 mois et ensuite tous les 6 mois durant les dix années suivantes. RESULTATS : Le suivit moyen de cette étude s'étend sur 101.5 ± 43.1, [3-144] mois (moyenne ± écart type, [étendue]). La pression intraoculaire (PIO) préopératoire était élevée à 26.8 ± 7.7, (14-52] mmHg, et l'acuité visuelle corrigée à 0.71 ± 0.33, [0.02-1.5]. Au terme des dix années après le traitement chirurgical, le nombre de patients suivit était de 52 avec une pression intraoculaire abaissée à 12.2 ± 4.7, [6-20] mmHg et une acuité visuelle corrigée de 0.63 ± 0.34, [0.01-1.2]. Le nombre de médicaments par patient a diminué de 2.3 ± 0.7, [ 1-4] à 1.3 ± 1.1, [0-3]. Dix ans après la SPIC, une pression intraoculaire <_ 21 mmHg sans médicaments (succès complet) était obtenue chez 47.7 % des patients et 89 % avec ou sans traitement médicamenteux (succès relatif). Les gestes postopératoires additionnels par gonioponcture ont été effectués sur 61 yeux (59.8%) et les injections sous-conjonctival de 5-fluorouracil ont été pratiquées sur 25 yeux dont 5 incluant un needling. CONCLUSIONS : Le suivit à long terme sur une période de dix ans, démontre que la sclérectomie profonde avec implant de collagène (SPIC) est efficace dans le contrôle de la pression intraoculaire et présente peu de complications postopératoires.

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The purpose of this study was to evaluate the intraocular pressure (IOP)-lowering effect of modified goniopuncture with the 532-nm Nd : YAG selective laser trabeculoplasty (SLT) laser on eyes after deep sclerectomy with collagen implant (DSCI). This was an interventional cased series. The effects of modified goniopuncture on eyes with insufficient IOP-lowering after DSCI were observed. Goniopuncture was performed using a Q-switched, frequency-doubled 532-nm Nd : YAG laser (SLT-goniopuncture, SLT-G). Outcome measures were amount of IOP-lowering and rapidity of decrease after laser intervention. In all, 10 eyes of 10 patients with a mean age of 71.0±7.7 (SD) years were treated with SLT-G. The mean time of SLT-G after DSCI procedure was 7.1±10.9 months. SLT-G decreased IOP from an average of 16.1±3.4 mm Hg to 14.2±2.8 mm Hg (after 15 min), 13.6±3.9 mm Hg (at 1 day), 12.5±4.1 mm Hg (at 1 month), and 12.6±2.5 (at 6 months) (P<0.0125). There were no complications related to the intervention. Patients in this series achieved an average 22.5% of IOP reduction after SLT-G. The use of the SLT laser appears to be an effective and safe alternative to the traditional Nd : YAG laser for goniopuncture in eyes after DSCI, with potential advantages related to non-perforation of trabeculo-descemet's membrane (TDM).

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Basé sur une expérience de terrain en archives médicales analysée notamment à l'aide de notions issues de l'ethnométhodologie, cet article entend revenir sur des aspects généralement invisibles de l'architecture de l'information telles les activités et personnes qui assurent sa production et son maintien. Utilisant la notion d'équipement des documents, nous proposons une incursion dans le monde de ceux qui réalisent ces opérations au quotidien, et produisent, par leur activité, une architecture de l'information située à partir de leurs compétences spécifiques. Nous discutons notamment des pratiques relatives à la numérisation des documents dans le contexte d'une architecture globale.

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quantiNemo is an individual-based, genetically explicit stochastic simulation program. It was developed to investigate the effects of selection, mutation, recombination and drift on quantitative traits with varying architectures in structured populations connected by migration and located in a heterogeneous habitat. quantiNemo is highly flexible at various levels: population, selection, trait(s) architecture, genetic map for QTL and/or markers, environment, demography, mating system, etc. quantiNemo is coded in C++ using an object-oriented approach and runs on any computer platform. Availability: Executables for several platforms, user's manual, and source code are freely available under the GNU General Public License at http://www2.unil.ch/popgen/softwares/quantinemo.

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This paper presents the recent history of a large prealpine lake (Lake Bourget) using chironomids, diatoms and organic matter analysis, and deals with the ability of paleolimnological approach to define an ecological reference state for the lake in the sense of the European Framework Directive. The study at low resolution of subfossil chironomids in a 4-m-long core shows the remarkable stability over the last 2.5 kyrs of the profundal community dominated by a Micropsectra-association until the beginning of the twentieth century, when oxyphilous taxa disappeared. Focusing on this key recent period, a high resolution and multiproxy study of two short cores reveals a progressive evolution of the lake's ecological state. Until AD 1880, Lake Bourget showed low organic matter content in the deep sediments (TOC less than 1%) and a well-oxygenated hypolimnion that allowed the development of a profundal oxyphilous chironomid fauna (Micropsectra-association). Diatom communities were characteristic of oligotrophic conditions. Around AD 1880, a slight increase in the TOC was the first sign of changes in lake conditions. This was followed by a first limited decline in oligotrophic diatom taxa and the disappearance of two oxyphilous chironomid taxa at the beginning of the twentieth century. The 1940s were a major turning point in recent lake history. Diatom assemblages and accumulation of well preserved planktonic organic matter in the sediment provide evidence of strong eutrophication. The absence of profundal chironomid communities reveals permanent hypolimnetic anoxia. From AD 1995 to 2006, the diatom assemblages suggest a reduction in nutrients, and a return to mesotrophic conditions, a result of improved wastewater management. However, no change in hypolimnion benthic conditions has been shown by either the organic matter or the subfossil chironomid profundal community. Our results emphasize the relevance of the paleolimnological approach for the assessment of reference conditions for modern lakes. Before AD 1900, the profundal Micropsectra-association and the Cyclotella dominated diatom community can be considered as the Lake Bourget reference community, which reflects the reference ecological state of the lake.

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BACKGROUND: For patients with acute iliofemoral deep vein thrombosis, it remains unclear whether the addition of intravascular high-frequency, low-power ultrasound energy facilitates the resolution of thrombosis during catheter-directed thrombolysis. METHODS AND RESULTS: In a controlled clinical trial, 48 patients (mean age 50 ± 21 years, 52% women) with acute iliofemoral deep vein thrombosis were randomized to receive ultrasound-assisted catheter-directed thrombolysis (N = 24) or conventional catheter-directed thrombolysis (N = 24). Thrombolysis regimen (20 mg r-tPA over 15 hours) was identical in all patients. The primary efficacy end point was the percentage of thrombus load reduction from baseline to 15 hours according to the length-adjusted thrombus score, obtained from standardized venograms and evaluated by a core laboratory blinded to group assignment. The percentage of thrombus load reduction was 55% ± 27% in the ultrasound-assisted catheter-directed thrombolysis group and 54% ± 27% in the conventional catheter-directed thrombolysis group (P = 0.91). Adjunctive angioplasty and stenting was performed in 19 (80%) patients and in 20 (83%) patients, respectively (P > 0.99). Treatment-related complications occurred in 3 (12%) and 2 (8%) patients, respectively (P > 0.99). At 3-month follow-up, primary venous patency was 100% in the ultrasound-assisted catheter-directed thrombolysis group and 96% in the conventional catheter-directed thrombolysis group (P = 0.33), and there was no difference in the severity of the post-thrombotic syndrome (mean Villalta score: 3.0 ± 3.9 [range 0-15] versus 1.9 ± 1.9 [range 0-7]; P=0.21), respectively. CONCLUSIONS: In this randomized controlled clinical trial of patients with acute iliofemoral deep vein thrombosis treated with a fixed-dose catheter thrombolysis regimen, the addition of intravascular ultrasound did not facilitate thrombus resolution. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01482273.

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Purpose: To examine the efficacy and safety of repeat deep sclerectomy (DS) versus Baerveldt shunt (BS) implantation as second line surgery following failed primary DS. Methods: Fifty one patients were prospectively recruited to undergo BS implantation following failed DS and 51 patients underwent repeat DS, for which data was collected retrospectively. All eyes had at least one failed DS. Surgical success was defined as IOP≤21mmHg and 20% reduction in IOP from baseline. Success rates, number of glaucoma medications (GMs), IOP, and complication rates were compared between the two groups at year 1, post-operatively. Results: Mean age, sex and the proportion of glaucoma subtypes were similar between groups. Preoperatively IOP was significantly lower in DS group vs BS group (18.8mmHg vs 23.8mmHg, p<0.01, two sample t-test). Postoperatively IOP was significantly higher in DS group than BS group (14.6mmHg vs 12.0mmHg, p<0.01, two-sample t-test). In the DS group, 47% of eyes did not achieve 20% reduction in IOP from baseline, as a result the success rates were significantly lower in eyes with DS (51%) than in eyes with BS (88%) (p=0.02, log-rank test). Preoperatively the number of GMs used in DS and BS groups were similar (2.2 vs 2.7 p=0.02, two sample t-test). Postoperatively there remained no significant difference in GMs between groups (0.9 vs 1.1, p= 0.58, two sample t-test). Complication rates were similar between the two groups (12% vs 10%). Conclusions: Baerveldt tube implantation was more effective in lowering IOP than repeat deep sclerectomy in eyes with failed primary DS, at year one. Complications were minor and infrequent in both groups

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Abstract Human experience takes place in the line of mental time (MT) created through 'self-projection' of oneself to different time-points in the past or future. Here we manipulated self-projection in MT not only with respect to one's life events but also with respect to one's faces from different past and future time-points. Behavioural and event-related functional magnetic resonance imaging activity showed three independent effects characterized by (i) similarity between past recollection and future imagination, (ii) facilitation of judgements related to the future as compared with the past, and (iii) facilitation of judgements related to time-points distant from the present. These effects were found with respect to faces and events, and also suggest that brain mechanisms of MT are independent of whether actual life episodes have to be re-experienced or pre-experienced, recruiting a common cerebral network including the anteromedial temporal, posterior parietal, inferior frontal, temporo-parietal and insular cortices. These behavioural and neural data suggest that self-projection in time is a fundamental aspect of MT, relying on neural structures encoding memory, mental imagery and self.