993 resultados para CORRELATE
Resumo:
The aim of this thesis was to clarify willingness and suitability for entrepreneurship among students of Lappeenranta University of Technology (LUT). In addition factors that would explain academic achievement and if there were relationship between academic achievement and willingness or suitability for entrepreneurship were examined. Questionnaires were sent via e-mail to 800 students of LUT in summer 2007. Response percent was 29,6 %. Based on the collected answers factors of entrepreneurial motivation and academic achievement were analyzed using mainly Pearson’s correlation coefficient and factor analysis. In the light of these factors willingness and suitability for entrepreneurship and academic achievement were examined. The results indicated that 36,7 % of the respondents were willing and 11,4 % were suitable for entrepreneurship. The largest share of the willing ones was focused on Department of Mechanical Engineering, whereas the smallest share on Department of Environmental Technology. The largest shares of the suitable ones were on Departments of Mechanical and Electrical Engineering, and the smallest shares on Departments of Environmental, Chemical and Energy Technology. Academic achievement was affected by, among others, exercising and success in high school. Academic achievement and willingness or suitability for entrepreneurship didn’t correlate. Yet, from factors of entrepreneurial motivation internal locus of control correlated positively with academic achievement.
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The applause sign was originally described as a quick bedside test to discriminate progressive supranuclear palsy (PSP) (positive applause sign, PAS) from Parkinson's disease (PD) and frontotemporal dementia (FTD) (negative applause sign). However, recent research demonstrated that the test is positive not only in a subset of patients with PD and FTD, but also in other neurodegenerative diseases. We tested 22 patients with amyotrophic lateral sclerosis (ALS) together with 22 healthy sex- and age-matched controls for the occurrence of PAS. Furthermore, we performed neuropsychological testing with the EXIT-25 battery to correlate PAS with neuropsychological deficits, especially frontal lobe dysfunction. Five ALS patients (23%) and none of the controls displayed PAS (p≤0.05). The occurrence of PAS in ALS patients was not correlated with pathologic EXIT-25 scores or subtests for aberrant motor behaviour. We describe for the first time the occurrence of the applause sign in ALS and provide additional evidence that PAS is not specific for Parkinsonian disorders. Although its occurrence has been related to aberrant motor behaviour due to frontal involvement, in our study PAS did not correlate with executive dysfunction as tested by the EXIT-25 test battery, or with subtests of aberrant motor behaviour.
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Autoantibodies against complement C1q (anti-C1q) strongly correlate with the occurrence of lupus nephritis and hypocomplementemia in systemic lupus erythematosus (SLE). Although a direct pathogenic role of anti-C1q has been suggested, the assumed complement-activating capacity remains to be elucidated. Using an ELISA-based assay, we found that anti-C1q activate the classical (CP) and lectin pathways (LP) depending on the anti-C1q immunoglobulin-class repertoire present in the patient's serum. IgG anti-C1q resulted in the activation of the CP as reflected by C4b deposition in the presence of purified C1 and C4 in a dose-dependent manner. The extent of C4b deposition correlated with anti-C1q levels in SLE patients but not in healthy controls. Our data indicate that SLE patient-derived anti-C1q can activate the CP and the LP but not the alternative pathway of complement. These findings are of importance for the understanding of the role of anti-C1q in SLE suggesting a direct link to hypocomplementemia.
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Most fishes produce free-living embryos that are exposed to environmental stressors immediately following fertilization, including pathogenic microorganisms. Initial immune protection of embryos involves the chorion, as a protective barrier, and maternally-allocated antimicrobial compounds. At later developmental stages, host-genetic effects influence susceptibility and tolerance, suggesting a direct interaction between embryo genes and pathogens. So far, only a few host genes could be identified that correlate with embryonic survival under pathogen stress in salmonids. Here, we utilized high-throughput RNA-sequencing in order to describe the transcriptional response of a non-model fish, the Alpine whitefish Coregonus palaea, to infection, both in terms of host genes that are likely manipulated by the pathogen, and those involved in an early putative immune response. Embryos were produced in vitro, raised individually, and exposed at the late-eyed stage to a virulent strain of the opportunistic fish pathogen Pseudomonas fluorescens. The pseudomonad increased embryonic mortality and affected gene expression substantially. For example, essential, upregulated metabolic pathways in embryos under pathogen stress included ion binding pathways, aminoacyl-tRNA-biosynthesis, and the production of arginine and proline, most probably mediated by the pathogen for its proliferation. Most prominently downregulated transcripts comprised the biosynthesis of unsaturated fatty acids, the citrate cycle, and various isoforms of b-cell transcription factors. These factors have been shown to play a significant role in host blood cell differentiation and renewal. With regard to specific immune functions, differentially expressed transcripts mapped to the complement cascade, MHC class I and II, TNF-alpha, and T-cell differentiation proteins. The results of this study reveal insights into how P. fluorescens impairs the development of whitefish embryos and set a foundation for future studies investigating host pathogen interactions in fish embryos.
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Numerous health benefits have been attributed to cocoa and its derived products in the last decade including antioxidant, anti-platelet and positive effects on lipid metabolism and vascular function. Inflammation plays a key role in the initiation and progression of atherosclerosis. However, cocoa feeding trials focused on inflammation are still rare and the results yielded are controversial. Health effects derived from cocoa consumption have been partly attributed to its polyphenol content, in particular of flavanols. Bioavailability is a key issue for cocoa polyphenols in order to be able to exert their biological activities. In the case of flavanols, bioavailability is strongly influenced by several factors, such as their degree of polymerization and the food matrix in which the polyphenols are delivered. Furthermore, gut has become an active site for the metabolism of procyanidins (oligomeric and polymeric flavanols). Estimation of polyphenol consumption or exposure is also a very challenging task in Food and Nutrition Science in order to correlate the intake of phytochemicals with in vivo health effects. In the area of nutrition, modern analytical techniques based on mass spectrometry are leading to considerable advances in targeted metabolite analysis and particularly in Metabolomics or global metabolite analysis. In this chapter we have summarized the most relevant results of our recent research on the bioavailability of cocoa polyphenols in humans and the effect of the matrix in which cocoa polyphenols are delivered considering both targeted analysis and a metabolomic approach. Furthermore, we have also summarized the effect of long-term consumption of cocoa powder in patients at high risk of cardiovascular disease (CVD) on the inflammatory biomarkers of atherosclerosis.
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Organochlorine compounds (OC) are known to induce vitamin A (retinoids) deficiency in mammals, which may be associated with impairment of immunocompetence, reproduction and growth. This makes retinoids a potentially useful biomarker of organochlorine impact on marine mammals. However, use of retinoids as a biomarker requires knowledge about its intrapopulation patterns of variation in natural conditions, information which is not currently available. We investigated these patterns in a cetacean population living in an unpolluted environment. 100 harbour porpoises Phocoena phocoena from West Greenland were sampled during the 1995 hunting season. Sex, age, morphometrics, nutritive condition, and retinol (following saponification) and OC levels in blubber were determined for each individual. OC levels found were extremely low and therefore considered unlikely to affect the population adversely: mean blubber concentrations, expressed on an extractable basis, were 2.04 (SD = 1.1) ppm for PCBs and 2.76 (SD = 1.66) ppm for tDDT. The mean blubber retinol concentration for the overall population was 59.66 (SD = 45.26) mu g g(-1). Taking into account the high contribution of blubber to body mass, blubber constitutes a significant body site for retinoid deposition in harbour porpoises. Retinol concentrations did not differ significantly between geographical regions or sexes, but they did correlate significantly (p <0.001) with age. Body condition, measured by determining the lipid content of the blubber, did not have a significant effect on retinol levels but the individuals examined were considered to be in an overall good nutritive condition. It is concluded that measurement of retinol concentrations in blubber samples is feasible and has a potential for use as a biomarker of organochlorine exposure in cetaceans. However, in order to do so, biological information, particularly age, is critical for the correct assessment of physiological impact
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PURPOSE: Pediatric rhabdomyosarcoma (RMS) has two common histologic subtypes: embryonal (ERMS) and alveolar (ARMS). PAX-FOXO1 fusion gene status is a more reliable prognostic marker than alveolar histology, whereas fusion gene-negative (FN) ARMS patients are clinically similar to ERMS patients. A five-gene expression signature (MG5) previously identified two diverse risk groups within the fusion gene-negative RMS (FN-RMS) patients, but this has not been independently validated. The goal of this study was to test whether expression of the MG5 metagene, measured using a technical platform that can be applied to routine pathology material, would correlate with outcome in a new cohort of patients with FN-RMS. EXPERIMENTAL DESIGN: Cases were taken from the Children's Oncology Group (COG) D9803 study of children with intermediate-risk RMS, and gene expression profiling for the MG5 genes was performed using the nCounter assay. The MG5 score was correlated with clinical and pathologic characteristics as well as overall and event-free survival. RESULTS: MG5 standardized score showed no significant association with any of the available clinicopathologic variables. The MG5 signature score showed a significant correlation with overall (N = 57; HR, 7.3; 95% CI, 1.9-27.0; P = 0.003) and failure-free survival (N = 57; HR, 6.1; 95% CI, 1.9-19.7; P = 0.002). CONCLUSIONS: This represents the first, validated molecular prognostic signature for children with FN-RMS who otherwise have intermediate-risk disease. The capacity to measure the expression of a small number of genes in routine pathology material and apply a simple mathematical formula to calculate the MG5 metagene score provides a clear path toward better risk stratification in future prospective clinical trials. Clin Cancer Res; 21(20); 4733-9. ©2015 AACR.
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The radial displacement of a fluid annulus in a rotating circular HeleShaw cell has been investigated experimentally. It has been found that the flow depends sensitively on the wetting conditions at the outer interface. Displacements in a prewet cell are well described by Darcy"s law in a wide range of experimental parameters, with little influence of capillary effects. In a dry cell, however, a more careful analysis of the interfacemotion is required; the interplay between a gradual loss of fluid at the inner interface, and the dependence of capillary forces at the outer interface on interfacial velocity and dynamic contact angle, result in a constant velocity for the interfaces. The experimental results in this case correlate in the form of an empirical scaling relation between the capillary number Ca and a dimensionless group, related to the ratio of centrifugal to capillary forces, which spans about three orders of magnitude in both quantities. Finally, the relative thickness of the coating film left by the inner interface is obtained as a function of Ca.
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Objectives: To correlate the chronic stimulated electrode position on postoperative MRI with the clinical response obtained in PD patients. Material and Method: We retrospectively reviewed 14 consecutive parkinsonian patients who were selected for STN-DBS surgery. Coordinates were determined on an IR T2 MRI coronal section per pendicular to AC-PC plane 3 mm posterior to midcommissural point (MCP) and 12 mm lateral to the midline the inferior aspect of subthalamic region. A CRW stereotactic frame was used for the surgical procedure. A 3D IR T2 MRI was performed postoperatively to determine the location of the stimulated contact in each patient. The clinical results were assessed independently by the neurological team. Results: All but 2 patients had monopolar stimulation. The mean coordinates of the stimulated contacts were: AP ^ ÿ4:23G1:4, Lat ^ 1:12G0:15, Vert ^ ÿ4:1 G2:7 to the MCP. With a mean follow-up of 8 months, all stimulated patients had a significant clinical improvement (preop/postop «ON» UPDRS: 25:8G7:0= 23:3 G8:6; preop/postop «OFF» UPDRS: 50:2G11:4=26:0 G7:8), 60% of them without any antiparkinsonian drug. Conclusion: According to the stereotactic atlas of Schaltenbrand and Warren and the 3D shape of the STN, our results show that our targetting is accurate and almost all the stimulated contacts are comprised in the STN volume. This indicates that MRI is a safe, precise and reproducible procedure for targetting the STN. The location of the stimulated contact within the STN volume is a good predictor of the clinical results.
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El present estudi s’emmarca en una investigació centrada en les persones grans de 65 a 84 anys del municipi de Canovelles. L’objectiu d’aquesta recerca és conèixer les principals motivacions i barreres d’aquest col·lectiu a l’hora d’anar al Complex Esportiu Municipal – Thalassa. Lligat amb els objectius marcats, la finalitat és relacionar els resultats amb possibles propostes de millora, per tal de minimitzar les barreres i potenciar les motivacions. Per obtenir els resultats s’ha passat un qüestionari a 40 persones demanant les raons per les quals van o no al complex. Un cop analitzats podem extreure, a tall de conclusions, que la principal motivació va relacionada amb temes de salut i la principal barrera amb temes econòmic, el cost mensual de la instal·lació per un abonat.
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Chromosome 22q11.2 deletion syndrome (22q11DS) is a genetic disease known to lead to cerebral structural alterations, which we study using the framework of the macroscopic white-matter connectome. We create weighted connectomes of 44 patients with 22q11DS and 44 healthy controls using diffusion tensor magnetic resonance imaging, and perform a weighted graph theoretical analysis. After confirming global network integration deficits in 22q11DS (previously identified using binary connectomes), we identify the spatial distribution of regions responsible for global deficits. Next, we further characterize the dysconnectivity of the deficient regions in terms of sub-network properties, and investigate their relevance with respect to clinical profiles. We define the subset of regions with decreased nodal integration (evaluated using the closeness centrality measure) as the affected core (A-core) of the 22q11DS structural connectome. A-core regions are broadly bilaterally symmetric and consist of numerous network hubs - chiefly parietal and frontal cortical, as well as subcortical regions. Using a simulated lesion approach, we demonstrate that these core regions and their connections are particularly important to efficient network communication. Moreover, these regions are generally densely connected, but less so in 22q11DS. These specific disturbances are associated to a rerouting of shortest network paths that circumvent the A-core in 22q11DS, "de-centralizing" the network. Finally, the efficiency and mean connectivity strength of an orbito-frontal/cingulate circuit, included in the affected regions, correlate negatively with the extent of negative symptoms in 22q11DS patients, revealing the clinical relevance of present findings. The identified A-core overlaps numerous regions previously identified as affected in 22q11DS as well as in schizophrenia, which approximately 30-40% of 22q11DS patients develop.
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Leptin is an adipocyte-secreted hormone, the circulating levels of which correlate closely with overall adiposity. Although rare mutations in the leptin (LEP) gene are well known to cause leptin deficiency and severe obesity, no common loci regulating circulating leptin levels have been uncovered. Therefore, we performed a genome-wide association study (GWAS) of circulating leptin levels from 32,161 individuals and followed up loci reaching P<10(-6) in 19,979 additional individuals. We identify five loci robustly associated (P<5 × 10(-8)) with leptin levels in/near LEP, SLC32A1, GCKR, CCNL1 and FTO. Although the association of the FTO obesity locus with leptin levels is abolished by adjustment for BMI, associations of the four other loci are independent of adiposity. The GCKR locus was found associated with multiple metabolic traits in previous GWAS and the CCNL1 locus with birth weight. Knockdown experiments in mouse adipose tissue explants show convincing evidence for adipogenin, a regulator of adipocyte differentiation, as the novel causal gene in the SLC32A1 locus influencing leptin levels. Our findings provide novel insights into the regulation of leptin production by adipose tissue and open new avenues for examining the influence of variation in leptin levels on adiposity and metabolic health.
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NlmCategory="UNASSIGNED">Objects' borders are readily perceived despite absent contrast gradients, e.g. due to poor lighting or occlusion. In humans, a visual evoked potential (VEP) correlate of illusory contour (IC) sensitivity, the "IC effect", has been identified with an onset at ~90ms and generators within bilateral lateral occipital cortices (LOC). The IC effect is observed across a wide range of stimulus parameters, though until now it always involved high-contrast achromatic stimuli. Whether IC perception and its brain mechanisms differ as a function of the type of stimulus cue remains unknown. Resolving such will provide insights on whether there is a unique or multiple solutions to how the brain binds together spatially fractionated information into a cohesive perception. Here, participants discriminated IC from no-contour (NC) control stimuli that were either comprised of low-contrast achromatic stimuli or instead isoluminant chromatic contrast stimuli (presumably biasing processing to the magnocellular and parvocellular pathways, respectively) on separate blocks of trials. Behavioural analyses revealed that ICs were readily perceived independently of the stimulus cue-i.e. when defined by either chromatic or luminance contrast. VEPs were analysed within an electrical neuroimaging framework and revealed a generally similar timing of IC effects across both stimulus contrasts (i.e. at ~90ms). Additionally, an overall phase shift of the VEP on the order of ~30ms was consistently observed in response to chromatic vs. luminance contrast independently of the presence/absence of ICs. Critically, topographic differences in the IC effect were observed over the ~110-160ms period; different configurations of intracranial sources contributed to IC sensitivity as a function of stimulus contrast. Distributed source estimations localized these differences to LOC as well as V1/V2. The present data expand current models by demonstrating the existence of multiple, cue-dependent circuits in the brain for generating perceptions of illusory contours.
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Focal epilepsy is increasingly recognized as the result of an altered brain network, both on the structural and functional levels and the characterization of these widespread brain alterations is crucial for our understanding of the clinical manifestation of seizure and cognitive deficits as well as for the management of candidates to epilepsy surgery. Tractography based on Diffusion Tensor Imaging allows non-invasive mapping of white matter tracts in vivo. Recently, diffusion spectrum imaging (DSI), based on an increased number of diffusion directions and intensities, has improved the sensitivity of tractography, notably with respect to the problem of fiber crossing and recent developments allow acquisition times compatible with clinical application. We used DSI and parcellation of the gray matter in regions of interest to build whole-brain connectivity matrices describing the mutual connections between cortical and subcortical regions in patients with focal epilepsy and healthy controls. In addition, the high angular and radial resolution of DSI allowed us to evaluate also some of the biophysical compartment models, to better understand the cause of the changes in diffusion anisotropy. Global connectivity, hub architecture and regional connectivity patterns were altered in TLE patients and showed different characteristics in RTLE vs LTLE with stronger abnormalities in RTLE. The microstructural analysis suggested that disturbed axonal density contributed more than fiber orientation to the connectivity changes affecting the temporal lobes whereas fiber orientation changes were more involved in extratemporal lobe changes. Our study provides further structural evidence that RTLE and LTLE are not symmetrical entities and DSI-based imaging could help investigate the microstructural correlate of these imaging abnormalities.
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CSL is a key transcription factor, mostly acting as a repressor, which has been shown to have a highly context-dependent function. While known as the main effector of Notch signaling, it can also exert Notch-independent functions. The downstream effects of the Notch/CSL signaling pathway and its involvement in several biological processes have been intensively studied. We recently showed that CSL is important to maintain skin homeostasis, as its specific deletion in mouse dermal fibroblasts -or downmodulation in human stromal fibroblasts- creates an inducing environment for squamous cell carcinoma (SCC) development, possibly due to the conversion of stromal fibroblasts into cancer associated fibroblasts (CAFs). Despite the wide interest in CSL as a transcriptional regulator, the mechanism of its own regulation has so far been neglected. We show here that CSL expression levels differ between individuals, and correlate among others with genes involved in DNA damage response. Starting from this finding we show that in dermal fibroblasts CSL is under transcriptional control of stress inducers such as UVA irradiation and Reactive Oxygen Species (ROS) induction, and that a main player in CSL transcriptional regulation is the transcription factor p53. In a separate line of work, we focused on individual variability, studying the differences in gene expression between human populations in various cancer types, particularly focusing on the Caucasian and African populations. It is indeed widely known that these populations have different incidences and mortalities for various cancers, and response to cancer treatment may also vary between them. We show here several genes that are differentially expressed and could be of interest in the study of population differences in cancer. -- CSL est un facteur de transcription agissant essentiellement comme répresseur, et qui a une fonction hautement dépendant du contexte. C'est l'effecteur principal de la voie de signalisation de Notch, mais il peut également exercer ses fonctions dans une façon Notch- indépendante. Nous avons récemment montré que CSL est important pour maintenir l'homéostasie de la peau. Sa suppression spécifique dans les fibroblastes dermiques de la souris ou dans les fibroblastes stromales humaines crée un environnement favorable pour le développement du carcinome épidermoïde (SCC), probablement en raison de la conversion des fibroblastes en fibroblastes associé au cancer (CAF). Malgré le grand intérêt de CSL comme régulateur transcriptionnel, le mécanisme de sa propre régulation a été jusqu'ici négligée. Nous montrons ici que dans les fibroblastes dermiques CSL est sous le contrôle transcriptionnel de facteurs de stress tels que l'irradiation UVA et l'induction des ROS dont p53 est l'acteur principal de cette régulation. Nous montrons aussi que les niveaux d'expression de CSL varient selon les individus, en corrélation avec d'autres gènes impliqués dans la réponse aux dommages de l'ADN. Dans une autre axe de recherche, concernant la variabilité individuelle, nous avons étudié les différences dans l'expression des gènes dans différents types de cancer entre les populations humaines, en se concentrant particulièrement sur les populations africaines et caucasiennes. Il est en effet bien connu que ces populations montrent des variations dans l'incidence des cancers, la mortalité, ainsi que pour les réponses au traitement. Nous montrons ici plusieurs gènes qui sont exprimés différemment et pourraient être digne d'intérêt dans l'étude du cancer au sein de différentes populations.