40 resultados para metadata harvesting


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Introduction: The field of Connectomic research is growing rapidly, resulting from methodological advances in structural neuroimaging on many spatial scales. Especially progress in Diffusion MRI data acquisition and processing made available macroscopic structural connectivity maps in vivo through Connectome Mapping Pipelines (Hagmann et al, 2008) into so-called Connectomes (Hagmann 2005, Sporns et al, 2005). They exhibit both spatial and topological information that constrain functional imaging studies and are relevant in their interpretation. The need for a special-purpose software tool for both clinical researchers and neuroscientists to support investigations of such connectome data has grown. Methods: We developed the ConnectomeViewer, a powerful, extensible software tool for visualization and analysis in connectomic research. It uses the novel defined container-like Connectome File Format, specifying networks (GraphML), surfaces (Gifti), volumes (Nifti), track data (TrackVis) and metadata. Usage of Python as programming language allows it to by cross-platform and have access to a multitude of scientific libraries. Results: Using a flexible plugin architecture, it is possible to enhance functionality for specific purposes easily. Following features are already implemented: * Ready usage of libraries, e.g. for complex network analysis (NetworkX) and data plotting (Matplotlib). More brain connectivity measures will be implemented in a future release (Rubinov et al, 2009). * 3D View of networks with node positioning based on corresponding ROI surface patch. Other layouts possible. * Picking functionality to select nodes, select edges, get more node information (ConnectomeWiki), toggle surface representations * Interactive thresholding and modality selection of edge properties using filters * Arbitrary metadata can be stored for networks, thereby allowing e.g. group-based analysis or meta-analysis. * Python Shell for scripting. Application data is exposed and can be modified or used for further post-processing. * Visualization pipelines using filters and modules can be composed with Mayavi (Ramachandran et al, 2008). * Interface to TrackVis to visualize track data. Selected nodes are converted to ROIs for fiber filtering The Connectome Mapping Pipeline (Hagmann et al, 2008) processed 20 healthy subjects into an average Connectome dataset. The Figures show the ConnectomeViewer user interface using this dataset. Connections are shown that occur in all 20 subjects. The dataset is freely available from the homepage (connectomeviewer.org). Conclusions: The ConnectomeViewer is a cross-platform, open-source software tool that provides extensive visualization and analysis capabilities for connectomic research. It has a modular architecture, integrates relevant datatypes and is completely scriptable. Visit www.connectomics.org to get involved as user or developer.

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BACKGROUND: This study was designed to determine whether the pain pattern in patients with an internal mammary artery (IMA) harvest differs from that in other cardiac operations and whether these patients present specific characteristics with clinical implications. METHODS: One hundred patients with left IMA grafting (IMA group) were compared prospectively with 100 patients who had a heart operation without IMA harvest (non-IMA group). Pain assessment was performed on postoperative days (POD) 1, 2, 3, and 7, and included pain intensity (10-point scale) and pain localization. RESULTS: In the IMA group, pain intensity was higher on POD 2 (4.2 +/- 2.4 versus 3.2 +/- 2.3, p < 0.01), and there were more patients without pain on POD 7 (32 versus 19, p = 0.03). In the IMA group, more patients had left basal thoracic pain throughout the entire study period and had sternal pain on POD 7, whereas more patients in the non-IMA group complained about back pain during the early postoperative period. CONCLUSIONS: The impact of IMA harvest on pain intensity is moderate, but the pain localization pattern of each group exhibits specific features that could help to better target pain management.

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Objective: To demonstrate successful in situ aortoiliac reconstruction of an infected infrarenal aneurysm using one single superficial femoral vein (SFV). Methods: In situ reconstruction using the right SFV sutured in end-to-end anastomosis with the aorta and distally with the right common iliac artery and in end-to-side anastomosis with the left common iliac artery. Results: The operating time was less than reported for aortic in situ reconstruction with bilateral SFV harvesting. The duplex scan 3 months postoperatively showed permeability of the bypass without any anastomotic stenosis or pseudoaneurysm. The right common femoral, popliteal, and greater saphenous veins were patent without thrombus, and the patient did not complain about peripheral edema. Conclusions: The use of only one instead of both the SFVs for aortobiiliac in situ reconstruction might be a way to reduce operating time and allow autogenous venous reconstruction even in patients with limited availability of venous material.

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BACKGROUND: The radial artery is routinely used as a graft for surgical arterial myocardial revascularization. The proximal radial artery anastomosis site remains unknown. In this study, we analyzed the short-term results and the operative risk determinants after having used four different common techniques for radial artery implantation. METHODS: From January 2000 to December 2004, 571 patients underwent coronary artery bypass grafting with radial arteries. Data were analyzed for the entire population and for subgroups following the proximal radial artery anastomosis site: 140 T-graft with the mammary artery (group A), 316 free-grafts with the proximal anastomosis to the ascending aorta (group B), 55 mammary arteries in situ elongated with the radial artery (group C) and 60 radial arteries elongated with a piece of mammary artery and anastomosed to the ascending aorta (group D). RESULTS: The mean age was 53.8 +/- 7.7 years; 55.5% of patients had a previous myocardial infarction and 73% presented with a satisfactory left ventricular function. A complete arterial myocardial revascularization was achieved in 532 cases (93.2%) and 90.2% of the procedures were performed under cardiopulmonary bypass and cardioplegic arrest. The operative mortality rate was 0.9%, a postoperative myocardial infarction was diagnosed in 19 patients (3.3%), an intra-aortic balloon pump was used in 10 patients (1.7%) and a mechanical circulatory device was implanted in 2 patients. The radial artery harvesting site remained always free from complications. The proximal radial artery anastomosis site was not a determinant of early hospital mortality. Group C showed a higher risk of postoperative myocardial infarction (p = 0.09), together with female gender (p = 0.003), hypertension (p = 0.059) and a longer cardiopulmonary bypass time. CONCLUSIONS: The radial artery and the mammary artery can guarantee multiple arterial revascularization also for patients with contraindications to double mammary artery use. The four most common techniques for proximal radial artery anastomosis are not related to a higher operative risk and they can be used alternatively to reach the best surgical results

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Knowledge of the pathological diagnosis before deciding the best strategy for treating parasellar lesions is of prime importance, due to the relative high morbidity and side-effects of open direct approaches to this region, known to be rich in important vasculo-nervous structures. When imaging is not evocative enough to ascertain an accurate pathological diagnosis, a percutaneous biopsy through the transjugal-transoval route (of Hartel) may be performed to guide the therapeutic decision.The chapter is based on the authors' experience in 50 patients who underwent the procedure over the ten past years. There was no mortality and only little (mostly transient) morbidity. Pathological diagnosis accuracy of the method revealed good, with a sensitivity of 0.83 and a specificity of 1.In the chapter the authors first recall the surgical anatomy background from personal laboratory dissections. They then describe the technical procedure, as well as the tissue harvesting method. Finally they define indications together with the decision-making process.Due to the constraint trajectory of the biopsy needle inserted through the Foramen Ovale, accessible lesions are only those located in the Meckel trigeminal Cave, the posterior sector of the cavernous sinus compartment, and the upper part of the petroclival region.The authors advise to perform this percutaneous biopsy method when imaging does not provide sufficient evidence of the pathological nature of the lesion, for therapeutic decision. Goal is to avoid unnecessary open surgery or radiosurgery, also inappropriate chemo-/radio-therapy.

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Chronic inhalation of grain dust is associated with asthma and chronic bronchitis in grain worker populations. Exposure to fungal particles was postulated to be an important etiologic agent of these pathologies. Fusarium species frequently colonize grain and straw and produce a wide array of mycotoxins that impact human health, necessitating an evaluation of risk exposure by inhalation of Fusarium and its consequences on immune responses. Data showed that Fusarium culmorum is a frequent constituent of aerosols sampled during wheat harvesting in the Vaud region of Switzerland. The aim of this study was to examine cytokine/chemokine responses and innate immune sensing of F. culmorum in bone-marrow-derived dendritic cells and macrophages. Overall, dendritic cells and macrophages responded to F. culmorum spores but not to its secreted components (i.e., mycotoxins) by releasing large amounts of macrophage inflammatory protein (MIP)-1α, MIP-1β, MIP-2, monocyte chemoattractant protein (MCP)-1, RANTES, and interleukin (IL)-12p40, intermediate amounts of tumor necrosis factor (TNF), IL-6, IL-12p70, IL-33, granulocyte colony-stimulating factor (G-CSF), and interferon gamma-induced protein (IP-10), but no detectable amounts of IL-4 and IL-10, a pattern of mediators compatible with generation of Th1 or Th17 antifungal protective immune responses rather than with Th2-dependent allergic responses. The sensing of F. culmorum spores by dendritic cells required dectin-1, the main pattern recognition receptor involved in β-glucans detection, but likely not MyD88 and TRIF-dependent Toll-like receptors. Taken together, our results indicate that F. culmorum stimulates potently innate immune cells in a dectin-1-dependent manner, suggesting that inhalation of F. culmorum from grain dust may promote immune-related airway diseases in exposed worker populations.

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Tissue engineering is a popular topic in peripheral nerve repair. Combining a nerve conduit with supporting adipose-derived cells could offer an opportunity to prevent time-consuming Schwann cell culture or the use of an autograft with its donor site morbidity and eventually improve clinical outcome. The aim of this study was to provide a broad overview over promising transplantable cells under equal experimental conditions over a long-term period. A 10-mm gap in the sciatic nerve of female Sprague-Dawley rats (7 groups of 7 animals, 8 weeks old) was bridged through a biodegradable fibrin conduit filled with rat adipose-derived stem cells (rASCs), differentiated rASCs (drASCs), human (h)ASCs from the superficial and deep abdominal layer, human stromal vascular fraction (SVF), or rat Schwann cells, respectively. As a control, we resutured a nerve segment as an autograft. Long-term evaluation was carried out after 12 weeks comprising walking track, morphometric, and MRI analyses. The sciatic functional index was calculated. Cross sections of the nerve, proximal, distal, and in between the two sutures, were analyzed for re-/myelination and axon count. Gastrocnemius muscle weights were compared. MRI proved biodegradation of the conduit. Differentiated rat ASCs performed significantly better than undifferentiated rASCs with less muscle atrophy and superior functional results. Superficial hASCs supported regeneration better than deep hASCs, in line with published in vitro data. The best regeneration potential was achieved by the drASC group when compared with other adipose tissue-derived cells. Considering the ease of procedure from harvesting to transplanting, we conclude that comparison of promising cells for nerve regeneration revealed that particularly differentiated ASCs could be a clinically translatable route toward new methods to enhance peripheral nerve repair.

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Occupational exposures to fungi are very frequent and are known to cause chronic or acute symptoms. To better assess health risks related to fungal exposure, it is crucial to characterize precisely the airborne fungal community in terms of quantity and composition. The objective of this chapter is to synthesize existing knowledge of airborne fungal contamination in various occupational settings. We analyzed 134 papers published between 2000 and 2014 focusing on five different work sectors considered as highly contaminated (i.e., more than 1000 fungal particles/m3): animal confinement buildings, sawmills, waste handling, the food industry, and grain/plant handling. Results show that harvesting grain, washing cheese, and handling salami seem to be the occupational situations with the worst potential for exposure. Moreover, a lack of standardized sampling and analysis methods among countries and even within the same country is highlighted. Occupational exposure limit values do not exist. Recommendations and guidelines based on culture-dependent methods, which are now recognized to underestimate true concentrations, are proposed. Those recommendations are frequently exceeded and protective measures are not always easy to implement.

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Chronic exposure to airborne fungi has been associated with different respiratory symptoms and pathologies in occupational populations, such as grain workers. However, the homogeneity in the fungal species composition of these bioaerosols on a large geographical scale and the different drivers that shape these fungal communities remain unclear. In this study, the diversity of fungi in grain dust and in the aerosols released during harvesting was determined across 96 sites at a geographical scale of 560 km(2) along an elevation gradient of 500 m by tag-encoded 454-pyrosequencing of the internal transcribed spacer (ITS) sequences. Associations between the structure of fungal communities in the grain dust and different abiotic (farming system, soil characteristics, geographic and climatic parameters) and biotic (wheat cultivar, previous crop culture) factors were explored. These analyses revealed a strong relationship between the airborne and grain dust fungal communities and showed the presence of allergenic and mycotoxigenic species in most samples, which highlights the potential contribution of these fungal species to work-related respiratory symptoms of grain workers. The farming system was the major driver of the alpha and beta phylogenetic diversity of fungal communities. In addition, elevation and soil CaCO3 concentrations shaped the alpha diversity whereas wheat cultivar, cropping history and the number of freezing days per year shaped the taxonomic beta diversity of these communities.

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UNLABELLED: Whole-genome sequencing (WGS) of 228 isolates was used to elucidate the origin and dynamics of a long-term outbreak of methicillin-resistant Staphylococcus aureus (MRSA) sequence type 228 (ST228) SCCmec I that involved 1,600 patients in a tertiary care hospital between 2008 and 2012. Combining of the sequence data with detailed metadata on patient admission and movement confirmed that the outbreak was due to the transmission of a single clonal variant of ST228, rather than repeated introductions of this clone into the hospital. We note that this clone is significantly more frequently recovered from groin and rectal swabs than other clones (P < 0.0001) and is also significantly more transmissible between roommates (P < 0.01). Unrecognized MRSA carriers, together with movements of patients within the hospital, also seem to have played a major role. These atypical colonization and transmission dynamics can help explain how the outbreak was maintained over the long term. This "stealthy" asymptomatic colonization of the gut, combined with heightened transmissibility (potentially reflecting a role for environmental reservoirs), means the dynamics of this outbreak share some properties with enteric pathogens such as vancomycin-resistant enterococci or Clostridium difficile. IMPORTANCE: Using whole-genome sequencing, we showed that a large and prolonged outbreak of methicillin-resistant Staphylococcus aureus was due to the clonal spread of a specific strain with genetic elements adapted to the hospital environment. Unrecognized MRSA carriers, the movement of patients within the hospital, and the low detection with clinical specimens were also factors that played a role in this occurrence. The atypical colonization of the gut means the dynamics of this outbreak may share some properties with enteric pathogens.