988 resultados para intermediate level vision


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PURPOSE: Apoptosis is known to play a key role in cell death after retinal ischemia. However, little is known about the kinetics of the signaling pathways involved and their contribution to this process. The aim of this study was to determine whether changes in the expression of molecules in the mitochondrial apoptotic pathway might explain the progression of retinal damage following ischemia/reperfusion. METHODS: Retinal ischemia was induced by elevating intraocular pressure in the vitreous cavity to 150 mmHg for a period of 60 min. At time 0, 3 h (early phase), and 24 h (late phase) after reperfusion, the retinas were harvested and modifications in the expression of Bax, Bak, Bcl-2, and Bcl-x(L) as well as caspase-3 and -7, were examined by qPCR and, in some cases, by western blot. RESULTS: qPCR analysis performed at the early phase after ischemia revealed a time dependent decrease in Bax, Bak, and Bcl-x(L) and no alteration in Bcl-2 mRNA expression in response to retinal ischemia. At the protein level, proapoptotic Bax and Bak were not modulated while Bcl-2 and Bcl-x(L) were significantly upregulated. At this stage, the Bax per Bcl-2 and Bax:Bcl-x(L) ratios were not modified. At the late phase of recovery, Bax and Bcl-x(L) mRNAs were downregulated while Bak was increased. Increased Bax:Bcl-2 and Bax:Bcl-x(L) ratios at both the mRNA and protein levels were observed 24 h after the ischemic insult. Analysis of caspases associated with mitochondria-mediated apoptosis revealed a specific increase in the expression of caspase-3 in the ischemic retinas 24 h after reperfusion, and a decrease in the expression of caspase-7. CONCLUSIONS: This study revealed that Bcl-2-related family members were differently regulated in the early and late phases after an ischemic insult. We showed that the Bax:Bcl-2 and Bax:Bcl-x(L) balances were not affected in the initial phases, but the Bax:Bcl-x(L) ratio shifted toward apoptosis during the late phase of recovery. This shift was reinforced by caspase-3 upregulation.

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SummaryLow-density lipoproteins (LDLs) have an important physiological role in organism transporting cholesterol and other fatty substances to target tissues. However, elevated LDL levels in the blood are associated with the formation of arterial plaques and consequently atherosclerosis. It is therefore important to characterize the intracellular pathways induced upon LDL stimulation as they might be involved in the pathological properties of these lipoproteins. It has been previously found that LDL stimulation of mouse embryonic fibroblasts activates p38 mitogen activated protein kinases (MAPKs). This leads to cell spreading and increase in the wound healing capabilities of the cells. These two responses might occur within atherosclerotic plaques.The aim of this project is to reveal the missing links between LDL particle and activation of p38 MAPK kinase. As previously shown in our lab activation of p38 MAPK kinase by the LDL particles occur independently of classical LDL receptor (LDLR). In this study we have shown that scavenger receptor type Β class I (SR-BI) is responsible for the signal transduction from the LDLs to the p38 MAPK. We have also shown that Mitogen activated kinase kinases (MKKs) that can directly activate ρ 38 MAPK in these conditions are MKK3 and MKK6 but not MKK4. We have also tested some of the intermediate components of the pathway like Ras and PI3 kinase but found that they do not play a role.The data obtained in this study showed a part of molecular mechanism responsible for p38 MAPK activation and subsequent wound healing and can contribute to our knowledge on function of the fibroblasts in the development of the atherosclerotic plaques.Diabetes Mellitus is a condition caused by disordered metabolism of blood glucose level. It is one of the most commonly spread disease in the western world, with the incidence reaching 8% of population in United States. Two most common types of diabetes are type 1 and 2 that differs slightly in the mechanism of the development. However in the basis of both types lies the cell death of pancreatic beta cells. The aim of this work is to improve beta cells survival in different pathophysiological settings. This could be extrapolated to the conditions in which Diabetes develops in humans. We decided to use RasGAP- derived fragment Ν with its strong antiapoptotic effect in beta cells. In our lab we have demonstrated that in the mild stress conditions RasGAP can be cleaved by caspases at the position 455 producing two fragments, fragment Ν and fragment C. Fragment Ν exerts

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BACKGROUND: Early diagnosis of postoperative orthopaedic infections is important in order to rapidly initiate adequate antimicrobial therapy. There are currently no reliable diagnostic markers to differentiate infectious from noninfectious causes of postoperative fever. We investigated the value of the serum procalcitonin level in febrile patients after orthopaedic surgery. METHODS: We prospectively evaluated 103 consecutive patients with new onset of fever within ten days after orthopaedic surgery. Fever episodes were classified by two independent investigators who were blinded to procalcitonin results as infectious or noninfectious origin. White blood-cell count, C-reactive protein level, and procalcitonin level were assessed on days 0, 1, and 3 of the postoperative fever. RESULTS: Infection was diagnosed in forty-five (44%) of 103 patients and involved the respiratory tract (eighteen patients), urinary tract (eighteen), joints (four), surgical site (two), bloodstream (two), and soft tissues (one). Unlike C-reactive protein levels and white blood-cell counts, procalcitonin values were significantly higher in patients with infection compared with patients without infection on the day of fever onset (p = 0.04), day 1 (p = 0.07), and day 3 (p = 0.003). Receiver-operating characteristics demonstrated that procalcitonin had the highest diagnostic accuracy, with a value of 0.62, 0.62, and 0.71 on days 0, 1, and 3, respectively. In a multivariate logistic regression analysis, procalcitonin was a significant predictor for postoperative infection on days 0, 1, and 3 of fever with an odds ratio of 2.3 (95% confidence interval, 1.1 to 4.4), 2.3 (95% confidence interval, 1.1 to 5.2), and 3.3 (95% confidence interval, 1.2 to 9.0), respectively. CONCLUSIONS: Serum procalcitonin is a helpful diagnostic marker supporting clinical and microbiological findings for more reliable differentiation of infectious from noninfectious causes of fever after orthopaedic surgery.

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BACKGROUND: Cardiovascular diseases (CVD) cause 1.8 million premature (<75 years) death annually in Europe. The majority of these deaths are preventable with the most efficient and cost-effective approach being on the population level. The aim of this position paper is to assist authorities in selecting the most adequate management strategies to prevent CVD. DESIGN AND METHODS: Experts reviewed and summarized the published evidence on the major modifiable CVD risk factors: food, physical inactivity, smoking, and alcohol. Population-based preventive strategies focus on fiscal measures (e.g. taxation), national and regional policies (e.g. smoke-free legislation), and environmental changes (e.g. availability of alcohol). RESULTS: Food is a complex area, but several strategies can be effective in increasing fruit and vegetables and lowering intake of salt, saturated fat, trans-fats, and free sugars. Tobacco and alcohol can be regulated mainly by fiscal measures and national policies, but local availability also plays a role. Changes in national policies and the built environment will integrate physical activity into daily life. CONCLUSION: Societal changes and commercial influences have led to the present unhealthy environment, in which default option in life style increases CVD risk. A challenge for both central and local authorities is, therefore, to ensure healthier defaults. This position paper summarizes the evidence and recommends a number of structural strategies at international, national, and regional levels that in combination can substantially reduce CVD.

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Meta-analysis of genome-wide association studies (GWASs) has led to the discoveries of many common variants associated with complex human diseases. There is a growing recognition that identifying "causal" rare variants also requires large-scale meta-analysis. The fact that association tests with rare variants are performed at the gene level rather than at the variant level poses unprecedented challenges in the meta-analysis. First, different studies may adopt different gene-level tests, so the results are not compatible. Second, gene-level tests require multivariate statistics (i.e., components of the test statistic and their covariance matrix), which are difficult to obtain. To overcome these challenges, we propose to perform gene-level tests for rare variants by combining the results of single-variant analysis (i.e., p values of association tests and effect estimates) from participating studies. This simple strategy is possible because of an insight that multivariate statistics can be recovered from single-variant statistics, together with the correlation matrix of the single-variant test statistics, which can be estimated from one of the participating studies or from a publicly available database. We show both theoretically and numerically that the proposed meta-analysis approach provides accurate control of the type I error and is as powerful as joint analysis of individual participant data. This approach accommodates any disease phenotype and any study design and produces all commonly used gene-level tests. An application to the GWAS summary results of the Genetic Investigation of ANthropometric Traits (GIANT) consortium reveals rare and low-frequency variants associated with human height. The relevant software is freely available.

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BACKGROUND: Multiple evanescent white dot syndrome (MEWDS) is a benign acquired isolated chorioretinal disorder. Symptoms include photopsia, visual blur and scotomas. Ocular examination reveals multiple white dots at the level of the deep retina. A parainfectious disorder was suggested but the exact mechanism of MEWDS is still unknown. Postulating that MEWDS might be an antigen driven inflammatory reaction, we analyzed HLA subtypes in patients with MEWDS. PATIENTS AND METHODS: Sixteen patients were diagnosed with MEWDS in Lausanne from 1985 to 1994. Blood was withdrawn in 9/16 patients. HLA-A, -B and -DR were sought. RESULTS: HLA-B51 was detected in 4/9 patients (44.4%). Other HLA subtypes were detected sporadically. CONCLUSIONS: The frequency of HLA-B51 haplotype was found to be 3.7 times more elevated than in a normal control caucasian group. This suggests the possibility that MEWDS might be a genetically determined disorder as it is the case for other ocular diseases like Birdshot chorioretinopathy (HLA-A29), Harada's disease (HLA-DRMT3), acute anterior uveitis (HLA-B27) or Behçet's disease (HLA-B51). We have no explanation for the presence of HLA-B51 in both Behçet's disease and MEWDS. The association of HLA-B51 and MEWDS needs confirmation by further testing.

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Atrial fibrillation (AF) is the most common arrhythmia and among the leading causes of stroke and heart failure in Western populations. Despite the increasing size of clinical trials assessing the efficacy and safety of AF therapies, achieved outcomes have not always matched expectations. Considering that AF is a symptom of many possible underlying diseases, clinical research for this arrhythmia should take into account their respective pathophysiology. Accordingly, the definition of the study populations to be included should rely on the established as well as on the new classifications of AF and take advantage from a differentiated look at the AF-electrocardiogram and from increasingly large spectrum of biomarkers. Such an integrated approach could bring researchers and treating physicians one step closer to the ultimate vision of personalized therapy, which, in this case, means an AF therapy based on refined diagnostic elements in accordance with scientific evidence gathered from clinical trials. By applying clear-cut patient inclusion criteria, future studies will be of smaller size and thus of lower cost. In addition, the findings from such studies will be of greater predictive value at the individual patient level, allowing for pinpointed therapeutic decisions in daily practice.

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Objective To analyze innovative contents on Early Child Development Promotion. Method This action-research involves nine faculties from four Higher Education Institutions at inner-state of São Paulo, Brazil.Data were collected by syllabi analyses (2009-2011), interviews and focus group. We have adopted an ECDP underpinning from international consensus, thus evaluating KT Results We have found relevant incorporation between teaching and extension in Nursing (87,5%) and Psychology (75%) undergraduate courses, while Pedagogy was restricted to teaching. Conclusion This KT evaluation has evinced innovative potential of extension, regardless teaching and research, for a better Early Childhood.


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Mountain ranges are biodiversity hotspots worldwide and provide refuge to many organisms under contemporary climate change. Gathering field information on mountain biodiversity over time is of primary importance to understand the response of biotic communities to climate changes. For plants, several long-term observation sites and networks of mountain biodiversity are emerging worldwide to gather field data and monitor altitudinal range shifts and community composition changes under contemporary climate change. Most of these monitoring sites, however, focus on alpine ecosystems and mountain summits, such as the global observation research initiative in alpine environments (GLORIA). Here we describe the Alps Vegetation Database, a comprehensive community level archive (GIVD ID EU-00-014) which aims at compiling all available geo-referenced vegetation plots from lowland forests to alpine grasslands across the greatest mountain range in Europe: the Alps. This research initiative was funded between 2008 and 2011 by the Danish Council for Independent Research and was part of a larger project to compare cross-scale plant community structure between the Alps and the Scandes. The Alps Vegetation Database currently harbours 35,731 geo-referenced vegetation plots and 5,023 valid taxa across Mediterranean, temperate and alpine environments. The data are mainly used by the main contributors of the Alps Vegetation Database in an ecoinformatics approach to test hypotheses related to plant macroecology and biogeography, but external proposals for joint collaborations are welcome.

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In cooperative multiagent systems, agents interac to solve tasks. Global dynamics of multiagent teams result from local agent interactions, and are complex and difficult to predict. Evolutionary computation has proven a promising approach to the design of such teams. The majority of current studies use teams composed of agents with identical control rules ("geneti- cally homogeneous teams") and select behavior at the team level ("team-level selection"). Here we extend current approaches to include four combinations of genetic team composition and level of selection. We compare the performance of genetically homo- geneous teams evolved with individual-level selection, genetically homogeneous teams evolved with team-level selection, genetically heterogeneous teams evolved with individual-level selection, and genetically heterogeneous teams evolved with team-level selection. We use a simulated foraging task to show that the optimal combination depends on the amount of cooperation required by the task. Accordingly, we distinguish between three types of cooperative tasks and suggest guidelines for the optimal choice of genetic team composition and level of selection